Remove bb_ prefixes from xfuncs.c (and a few other places), consolidate
[oweals/busybox.git] / shell / ash.c
index 99d5e7d740e768a6573707257c1d346837f20472..c1b2b0ed658a4cdced95719c535bfb29d28eaf45 100644 (file)
@@ -5,46 +5,70 @@
  * Copyright (c) 1989, 1991, 1993, 1994
  *      The Regents of the University of California.  All rights reserved.
  *
- * This code is derived from software contributed to Berkeley by
- * Kenneth Almquist.
+ * Copyright (c) 1997-2005 Herbert Xu <herbert@gondor.apana.org.au>
+ * was re-ported from NetBSD and debianized.
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
  *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
+ * This code is derived from software contributed to Berkeley by
+ * Kenneth Almquist.
  *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
  *
- * This version of ash is adapted from the source in Debian's ash 0.3.8-5
- * package.
+ * Original BSD copyright notice is retained at the end of this file.
+ */
+
+/*
+ * rewrite arith.y to micro stack based cryptic algorithm by
+ * Copyright (c) 2001 Aaron Lehmann <aaronl@vitelus.com>
  *
- * Modified by Erik Andersen <andersee@debian.org> and
- * Vladimir Oleynik <dzo@simtreas.ru> to be used in busybox
+ * Modified by Paul Mundt <lethal@linux-sh.org> (c) 2004 to support
+ * dynamic variables.
  *
+ * Modified by Vladimir Oleynik <dzo@simtreas.ru> (c) 2001-2005 to be
+ * used in busybox and size optimizations,
+ * rewrote arith (see notes to this), added locale support,
+ * rewrote dynamic variables.
  *
- * Original copyright notice is retained at the end of this file.
  */
 
 
-/* Enable this to compile in extra debugging noise.  When debugging is
- * on, debugging info will be written to $HOME/trace and a quit signal
- * will generate a core dump. */
-#undef DEBUG
+/*
+ * The follow should be set to reflect the type of system you have:
+ *      JOBS -> 1 if you have Berkeley job control, 0 otherwise.
+ *      define SYSV if you are running under System V.
+ *      define DEBUG=1 to compile in debugging ('set -o debug' to turn on)
+ *      define DEBUG=2 to compile in and turn on debugging.
+ *
+ * When debugging is on, debugging info will be written to ./trace and
+ * a quit signal will generate a core dump.
+ */
+
 
-/* These are here to work with glibc -- Don't change these... */
-#undef FNMATCH_BROKEN
-#undef GLOB_BROKEN
 #define IFS_BROKEN
 
-#include <assert.h>
+#define PROFILE 0
+
+#include "busybox.h"
+
+#ifdef DEBUG
+#define _GNU_SOURCE
+#endif
+
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/param.h>
+#include <sys/resource.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <stdarg.h>
 #include <stddef.h>
+#include <assert.h>
 #include <ctype.h>
 #include <dirent.h>
 #include <errno.h>
 #include <paths.h>
 #include <setjmp.h>
 #include <signal.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sysexits.h>
-#include <unistd.h>
-#include <sys/stat.h>
-#include <sys/cdefs.h>
-#include <sys/ioctl.h>
-#include <sys/param.h>
-#include <sys/resource.h>
-#include <sys/time.h>
-#include <sys/times.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include "pwd.h"
+/*#include <stdint.h>*/
+#include <time.h>
+#include <fnmatch.h>
 
+#include "pwd_.h"
 
-#if !defined(FNMATCH_BROKEN)
-#include <fnmatch.h>
-#endif
-#if !defined(GLOB_BROKEN)
-#include <glob.h>
+#ifdef CONFIG_ASH_JOB_CONTROL
+#define JOBS 1
+#else
+#undef JOBS
 #endif
 
-#ifdef CONFIG_ASH_JOB_CONTROL
+#if JOBS || defined(CONFIG_ASH_READ_NCHARS)
 #include <termios.h>
 #endif
 
-#include "busybox.h"
 #include "cmdedit.h"
 
-/*
- * This file was generated by the mksyntax program.
- */
+#ifdef __GLIBC__
+/* glibc sucks */
+static int *dash_errno;
+#undef errno
+#define errno (*dash_errno)
+#endif
 
-/* Syntax classes */
-#define CWORD 0                 /* character is nothing special */
-#define CNL 1                   /* newline character */
-#define CBACK 2                 /* a backslash character */
-#define CSQUOTE 3               /* single quote */
-#define CDQUOTE 4               /* double quote */
-#define CENDQUOTE 5             /* a terminating quote */
-#define CBQUOTE 6               /* backwards single quote */
-#define CVAR 7                  /* a dollar sign */
-#define CENDVAR 8               /* a '}' character */
-#define CLP 9                   /* a left paren in arithmetic */
-#define CRP 10                  /* a right paren in arithmetic */
-#define CENDFILE 11             /* end of file */
-#define CCTL 12                 /* like CWORD, except it must be escaped */
-#define CSPCL 13                /* these terminate a word */
-#define CIGN 14                 /* character should be ignored */
+#if defined(__uClinux__)
+#error "Do not even bother, ash will not run on uClinux"
+#endif
 
-#define SYNBASE 130
-#define PEOF -130
+#ifdef DEBUG
+#define _DIAGASSERT(assert_expr) assert(assert_expr)
+#else
+#define _DIAGASSERT(assert_expr)
+#endif
 
-#define PEOA -129
 
-#define TEOF 0
-#define TNL 1
-#define TREDIR 2
-#define TWORD 3
-#define TASSIGN 4
-#define TSEMI 5
-#define TBACKGND 6
-#define TAND 7
-#define TOR 8
-#define TPIPE 9
-#define TLP 10
-#define TRP 11
-#define TENDCASE 12
-#define TENDBQUOTE 13
-#define TNOT 14
-#define TCASE 15
-#define TDO 16
-#define TDONE 17
-#define TELIF 18
-#define TELSE 19
-#define TESAC 20
-#define TFI 21
-#define TFOR 22
-#define TIF 23
-#define TIN 24
-#define TTHEN 25
-#define TUNTIL 26
-#define TWHILE 27
-#define TBEGIN 28
-#define TEND 29
+#ifdef CONFIG_ASH_ALIAS
+/*      alias.h       */
 
+#define ALIASINUSE      1
+#define ALIASDEAD       2
 
+struct alias {
+       struct alias *next;
+       char *name;
+       char *val;
+       int flag;
+};
 
-/* control characters in argument strings */
-#define CTLESC '\201'
-#define CTLVAR '\202'
-#define CTLENDVAR '\203'
-#define CTLBACKQ '\204'
-#define CTLQUOTE 01             /* ored with CTLBACKQ code if in quotes */
-/*      CTLBACKQ | CTLQUOTE == '\205' */
-#define CTLARI  '\206'
-#define CTLENDARI '\207'
-#define CTLQUOTEMARK '\210'
+static struct alias *lookupalias(const char *, int);
+static int aliascmd(int, char **);
+static int unaliascmd(int, char **);
+static void rmaliases(void);
+static int unalias(const char *);
+static void printalias(const struct alias *);
+#endif
 
+/*      cd.h  */
 
-#define is_digit(c)     ((c)>='0' && (c)<='9')
-#define is_name(c)      (((c) < CTLESC || (c) > CTLENDARI) && ((c) == '_' || isalpha((unsigned char) (c))))
-#define is_in_name(c)   (((c) < CTLESC || (c) > CTLENDARI) && ((c) == '_' || isalnum((unsigned char) (c))))
 
-/*
- * is_special(c) evaluates to 1 for c in "!#$*-0123456789?@"; 0 otherwise
- * (assuming ascii char codes, as the original implementation did)
- */
-#define is_special(c) \
-    ( (((unsigned int)c) - 33 < 32) \
-                        && ((0xc1ff920dUL >> (((unsigned int)c) - 33)) & 1))
+static void    setpwd(const char *, int);
 
-#define digit_val(c)    ((c) - '0')
+/*      error.h      */
 
 
-#define S_DFL 1                 /* default signal handling (SIG_DFL) */
-#define S_CATCH 2               /* signal is caught */
-#define S_IGN 3                 /* signal is ignored (SIG_IGN) */
-#define S_HARD_IGN 4            /* signal is ignored permenantly */
-#define S_RESET 5               /* temporary - to reset a hard ignored sig */
+/*
+ * Types of operations (passed to the errmsg routine).
+ */
 
 
-/* variable substitution byte (follows CTLVAR) */
-#define VSTYPE  0x0f            /* type of variable substitution */
-#define VSNUL   0x10            /* colon--treat the empty string as unset */
-#define VSQUOTE 0x80            /* inside double quotes--suppress splitting */
+static const char not_found_msg[] = "%s: not found";
 
-/* values of VSTYPE field */
-#define VSNORMAL        0x1             /* normal variable:  $var or ${var} */
-#define VSMINUS         0x2             /* ${var-text} */
-#define VSPLUS          0x3             /* ${var+text} */
-#define VSQUESTION      0x4             /* ${var?message} */
-#define VSASSIGN        0x5             /* ${var=text} */
-#define VSTRIMLEFT      0x6             /* ${var#pattern} */
-#define VSTRIMLEFTMAX   0x7             /* ${var##pattern} */
-#define VSTRIMRIGHT     0x8             /* ${var%pattern} */
-#define VSTRIMRIGHTMAX  0x9             /* ${var%%pattern} */
-#define VSLENGTH        0xa             /* ${#var} */
 
-/* flags passed to redirect */
-#define REDIR_PUSH 01           /* save previous values of file descriptors */
-#define REDIR_BACKQ 02          /* save the command output to pipe */
+#define E_OPEN  "No such file"          /* opening a file */
+#define E_CREAT "Directory nonexistent" /* creating a file */
+#define E_EXEC  not_found_msg+4         /* executing a program */
 
 /*
- * BSD setjmp saves the signal mask, which violates ANSI C and takes time,
- * so we use _setjmp instead.
+ * We enclose jmp_buf in a structure so that we can declare pointers to
+ * jump locations.  The global variable handler contains the location to
+ * jump to when an exception occurs, and the global variable exception
+ * contains a code identifying the exception.  To implement nested
+ * exception handlers, the user should save the value of handler on entry
+ * to an inner scope, set handler to point to a jmploc structure for the
+ * inner scope, and restore handler on exit from the scope.
  */
 
-#if defined(BSD)
-#define setjmp(jmploc)  _setjmp(jmploc)
-#define longjmp(jmploc, val)    _longjmp(jmploc, val)
-#endif
+struct jmploc {
+       jmp_buf loc;
+};
 
-/*
- * Most machines require the value returned from malloc to be aligned
- * in some way.  The following macro will get this right on many machines.
- */
+static struct jmploc *handler;
+static int exception;
+static volatile int suppressint;
+static volatile sig_atomic_t intpending;
 
-#ifndef ALIGN
-union align {
-       int i;
-       char *cp;
-};
+/* exceptions */
+#define EXINT 0         /* SIGINT received */
+#define EXERROR 1       /* a generic error */
+#define EXSHELLPROC 2   /* execute a shell procedure */
+#define EXEXEC 3        /* command execution failed */
+#define EXEXIT 4        /* exit the shell */
+#define EXSIG 5         /* trapped signal in wait(1) */
 
-#define ALIGN(nbytes)   (((nbytes) + sizeof(union align) - 1) & ~(sizeof(union align) - 1))
-#endif
 
-#ifdef CONFIG_LOCALE_SUPPORT
-#include <locale.h>
-static void change_lc_all(const char *value);
-static void change_lc_ctype(const char *value);
-#endif
+/* do we generate EXSIG events */
+static int exsig;
+/* last pending signal */
+static volatile sig_atomic_t pendingsigs;
 
 /*
  * These macros allow the user to suspend the handling of interrupt signals
@@ -236,102 +194,134 @@ static void change_lc_ctype(const char *value);
  * more fun than worrying about efficiency and portability. :-))
  */
 
-static void onint (void);
-static volatile int suppressint;
-static volatile int intpending;
+#define xbarrier() ({ __asm__ __volatile__ ("": : :"memory"); })
+#define INTOFF \
+       ({ \
+               suppressint++; \
+               xbarrier(); \
+               0; \
+       })
+#define SAVEINT(v) ((v) = suppressint)
+#define RESTOREINT(v) \
+       ({ \
+               xbarrier(); \
+               if ((suppressint = (v)) == 0 && intpending) onint(); \
+               0; \
+       })
+#define EXSIGON() \
+       ({ \
+               exsig++; \
+               xbarrier(); \
+               if (pendingsigs) \
+                       exraise(EXSIG); \
+               0; \
+       })
+/* EXSIG is turned off by evalbltin(). */
+
+
+static void exraise(int) ATTRIBUTE_NORETURN;
+static void onint(void) ATTRIBUTE_NORETURN;
+
+static void sh_error(const char *, ...) ATTRIBUTE_NORETURN;
+static void exerror(int, const char *, ...) ATTRIBUTE_NORETURN;
+
+static void sh_warnx(const char *, ...);
 
-#define INTOFF suppressint++
-#ifndef CONFIG_ASH_OPTIMIZE_FOR_SIZE
-#define INTON { if (--suppressint == 0 && intpending) onint(); }
-#define FORCEINTON {suppressint = 0; if (intpending) onint();}
-#else
-static void __inton (void);
-static void forceinton (void);
-#define INTON __inton()
+#ifdef CONFIG_ASH_OPTIMIZE_FOR_SIZE
+static void
+inton(void) {
+       if (--suppressint == 0 && intpending) {
+               onint();
+       }
+}
+#define INTON inton()
+static void forceinton(void)
+{
+       suppressint = 0;
+       if (intpending)
+               onint();
+}
 #define FORCEINTON forceinton()
-#endif
-
-#define CLEAR_PENDING_INT intpending = 0
-#define int_pending() intpending
+#else
+#define INTON \
+       ({ \
+               xbarrier(); \
+               if (--suppressint == 0 && intpending) onint(); \
+               0; \
+       })
+#define FORCEINTON \
+       ({ \
+               xbarrier(); \
+               suppressint = 0; \
+               if (intpending) onint(); \
+               0; \
+       })
+#endif /* CONFIG_ASH_OPTIMIZE_FOR_SIZE */
+
+/*      expand.h     */
 
+struct strlist {
+       struct strlist *next;
+       char *text;
+};
 
-typedef void *pointer;
-#ifndef NULL
-#define NULL (void *)0
-#endif
 
-static pointer stalloc (int);
-static void stunalloc (pointer);
-static void ungrabstackstr (char *, char *);
-static char * growstackstr(void);
-static char * makestrspace(size_t newlen);
-static char *sstrdup (const char *);
+struct arglist {
+       struct strlist *list;
+       struct strlist **lastp;
+};
 
 /*
- * Parse trees for commands are allocated in lifo order, so we use a stack
- * to make this more efficient, and also to avoid all sorts of exception
- * handling code to handle interrupts in the middle of a parse.
- *
- * The size 504 was chosen because the Ultrix malloc handles that size
- * well.
+ * expandarg() flags
  */
+#define EXP_FULL        0x1     /* perform word splitting & file globbing */
+#define EXP_TILDE       0x2     /* do normal tilde expansion */
+#define EXP_VARTILDE    0x4     /* expand tildes in an assignment */
+#define EXP_REDIR       0x8     /* file glob for a redirection (1 match only) */
+#define EXP_CASE        0x10    /* keeps quotes around for CASE pattern */
+#define EXP_RECORD      0x20    /* need to record arguments for ifs breakup */
+#define EXP_VARTILDE2   0x40    /* expand tildes after colons only */
+#define EXP_WORD        0x80    /* expand word in parameter expansion */
+#define EXP_QWORD       0x100   /* expand word in quoted parameter expansion */
 
-#define MINSIZE 504             /* minimum size of a block */
-
-
-struct stack_block {
-       struct stack_block *prev;
-       char space[MINSIZE];
-};
-
-static struct stack_block stackbase;
-static struct stack_block *stackp = &stackbase;
-static struct stackmark *markp;
-static char *stacknxt = stackbase.space;
-static int stacknleft = MINSIZE;
-
-
-#define equal(s1, s2)   (strcmp(s1, s2) == 0)
 
-#define stackblock() stacknxt
-#define stackblocksize() stacknleft
-#define STARTSTACKSTR(p)        p = stackblock(), sstrnleft = stackblocksize()
+union node;
+static void expandarg(union node *, struct arglist *, int);
+#define rmescapes(p) _rmescapes((p), 0)
+static char *_rmescapes(char *, int);
+static int casematch(union node *, char *);
 
-#define STPUTC(c, p)    (--sstrnleft >= 0? (*p++ = (c)) : (p = growstackstr(), *p++ = (c)))
-#define CHECKSTRSPACE(n, p)     { if (sstrnleft < n) p = makestrspace(n); }
-#define STACKSTRNUL(p)  (sstrnleft == 0? (p = growstackstr(), *p = '\0') : (*p = '\0'))
+#ifdef CONFIG_ASH_MATH_SUPPORT
+static void expari(int);
+#endif
 
+/*      eval.h       */
 
-#define USTPUTC(c, p)   (--sstrnleft, *p++ = (c))
-#define STUNPUTC(p)     (++sstrnleft, --p)
-#define STTOPC(p)       p[-1]
-#define STADJUST(amount, p)     (p += (amount), sstrnleft -= (amount))
-#define grabstackstr(p) stalloc(stackblocksize() - sstrnleft)
+static char *commandname;              /* currently executing command */
+static struct strlist *cmdenviron;     /* environment for builtin command */
+static int exitstatus;                 /* exit status of last command */
+static int back_exitstatus;            /* exit status of backquoted command */
 
-#define ckfree(p)       free((pointer)(p))
 
+struct backcmd {                /* result of evalbackcmd */
+       int fd;                 /* file descriptor to read from */
+       char *buf;              /* buffer */
+       int nleft;              /* number of chars in buffer */
+       struct job *jp;         /* job structure for command */
+};
 
-#ifdef DEBUG
-#define TRACE(param)    trace param
-typedef union node unode;
-static void trace (const char *, ...);
-static void trargs (char **);
-static void showtree (unode *);
-static void trputc (int);
-static void trputs (const char *);
-static void opentrace (void);
-#else
-#define TRACE(param)
-#endif
+/*
+ * This file was generated by the mknodes program.
+ */
 
-#define NSEMI 0
-#define NCMD 1
-#define NPIPE 2
-#define NREDIR 3
-#define NBACKGND 4
-#define NSUBSHELL 5
-#define NAND 6
-#define NOR 7
+#define NCMD 0
+#define NPIPE 1
+#define NREDIR 2
+#define NBACKGND 3
+#define NSUBSHELL 4
+#define NAND 5
+#define NOR 6
+#define NSEMI 7
 #define NIF 8
 #define NWHILE 9
 #define NUNTIL 10
@@ -341,105 +331,44 @@ static void opentrace (void);
 #define NDEFUN 14
 #define NARG 15
 #define NTO 16
-#define NFROM 17
-#define NFROMTO 18
-#define NAPPEND 19
-#define NTOOV 20
+#define NCLOBBER 17
+#define NFROM 18
+#define NFROMTO 19
+#define NAPPEND 20
 #define NTOFD 21
 #define NFROMFD 22
 #define NHERE 23
 #define NXHERE 24
 #define NNOT 25
 
-/*
- * expandarg() flags
- */
-#define EXP_FULL        0x1     /* perform word splitting & file globbing */
-#define EXP_TILDE       0x2     /* do normal tilde expansion */
-#define EXP_VARTILDE    0x4     /* expand tildes in an assignment */
-#define EXP_REDIR       0x8     /* file glob for a redirection (1 match only) */
-#define EXP_CASE        0x10    /* keeps quotes around for CASE pattern */
-#define EXP_RECORD      0x20    /* need to record arguments for ifs breakup */
 
 
-#define NOPTS   16
-
-static char optet_vals[NOPTS];
-
-static const char * const optlist[NOPTS] = {
-       "e" "errexit",
-       "f" "noglob",
-       "I" "ignoreeof",
-       "i" "interactive",
-       "m" "monitor",
-       "n" "noexec",
-       "s" "stdin",
-       "x" "xtrace",
-       "v" "verbose",
-       "V" "vi",
-       "E" "emacs",
-       "C" "noclobber",
-       "a" "allexport",
-       "b" "notify",
-       "u" "nounset",
-       "q" "quietprofile"
+struct ncmd {
+      int type;
+      union node *assign;
+      union node *args;
+      union node *redirect;
 };
 
-#define optent_name(optent) (optent+1)
-#define optent_letter(optent) optent[0]
-#define optent_val(optent) optet_vals[optent]
-
-#define eflag optent_val(0)
-#define fflag optent_val(1)
-#define Iflag optent_val(2)
-#define iflag optent_val(3)
-#define mflag optent_val(4)
-#define nflag optent_val(5)
-#define sflag optent_val(6)
-#define xflag optent_val(7)
-#define vflag optent_val(8)
-#define Vflag optent_val(9)
-#define Eflag optent_val(10)
-#define Cflag optent_val(11)
-#define aflag optent_val(12)
-#define bflag optent_val(13)
-#define uflag optent_val(14)
-#define qflag optent_val(15)
-
 
-/* Mode argument to forkshell.  Don't change FORK_FG or FORK_BG. */
-#define FORK_FG 0
-#define FORK_BG 1
-#define FORK_NOJOB 2
+struct npipe {
+      int type;
+      int backgnd;
+      struct nodelist *cmdlist;
+};
 
 
-struct nbinary {
-      int type;
-      union node *ch1;
-      union node *ch2;
-};
-
-
-struct ncmd {
+struct nredir {
       int type;
-      int backgnd;
-      union node *assign;
-      union node *args;
+      union node *n;
       union node *redirect;
 };
 
 
-struct npipe {
-      int type;
-      int backgnd;
-      struct nodelist *cmdlist;
-};
-
-
-struct nredir {
+struct nbinary {
       int type;
-      union node *n;
-      union node *redirect;
+      union node *ch1;
+      union node *ch2;
 };
 
 
@@ -516,10 +445,10 @@ struct nnot {
 
 union node {
       int type;
-      struct nbinary nbinary;
       struct ncmd ncmd;
       struct npipe npipe;
       struct nredir nredir;
+      struct nbinary nbinary;
       struct nif nif;
       struct nfor nfor;
       struct ncase ncase;
@@ -537,32 +466,66 @@ struct nodelist {
        union node *n;
 };
 
-struct backcmd {                /* result of evalbackcmd */
-       int fd;                 /* file descriptor to read from */
-       char *buf;              /* buffer */
-       int nleft;              /* number of chars in buffer */
-       struct job *jp;         /* job structure for command */
-};
 
-struct cmdentry {
-       int cmdtype;
-       union param {
-               int index;
-               union node *func;
-               const struct builtincmd *cmd;
-       } u;
+struct funcnode {
+       int count;
+       union node n;
 };
 
-struct strlist {
-       struct strlist *next;
-       char *text;
-};
 
+static void freefunc(struct funcnode *);
+/*      parser.h     */
 
-struct arglist {
-       struct strlist *list;
-       struct strlist **lastp;
-};
+/* control characters in argument strings */
+#define CTL_FIRST '\201'        /* first 'special' character */
+#define CTLESC '\201'           /* escape next character */
+#define CTLVAR '\202'           /* variable defn */
+#define CTLENDVAR '\203'
+#define CTLBACKQ '\204'
+#define CTLQUOTE 01             /* ored with CTLBACKQ code if in quotes */
+/*      CTLBACKQ | CTLQUOTE == '\205' */
+#define CTLARI  '\206'          /* arithmetic expression */
+#define CTLENDARI '\207'
+#define CTLQUOTEMARK '\210'
+#define CTL_LAST '\210'         /* last 'special' character */
+
+/* variable substitution byte (follows CTLVAR) */
+#define VSTYPE  0x0f            /* type of variable substitution */
+#define VSNUL   0x10            /* colon--treat the empty string as unset */
+#define VSQUOTE 0x80            /* inside double quotes--suppress splitting */
+
+/* values of VSTYPE field */
+#define VSNORMAL        0x1             /* normal variable:  $var or ${var} */
+#define VSMINUS         0x2             /* ${var-text} */
+#define VSPLUS          0x3             /* ${var+text} */
+#define VSQUESTION      0x4             /* ${var?message} */
+#define VSASSIGN        0x5             /* ${var=text} */
+#define VSTRIMRIGHT     0x6             /* ${var%pattern} */
+#define VSTRIMRIGHTMAX  0x7             /* ${var%%pattern} */
+#define VSTRIMLEFT      0x8             /* ${var#pattern} */
+#define VSTRIMLEFTMAX   0x9             /* ${var##pattern} */
+#define VSLENGTH        0xa             /* ${#var} */
+
+/* values of checkkwd variable */
+#define CHKALIAS        0x1
+#define CHKKWD          0x2
+#define CHKNL           0x4
+
+#define IBUFSIZ (BUFSIZ + 1)
+
+/*
+ * NEOF is returned by parsecmd when it encounters an end of file.  It
+ * must be distinct from NULL, so we use the address of a variable that
+ * happens to be handy.
+ */
+static int plinno = 1;                  /* input line number */
+
+/* number of characters left in input buffer */
+static int parsenleft;                  /* copy of parsefile->nleft */
+static int parselleft;                  /* copy of parsefile->lleft */
+
+/* next character in input buffer */
+static char *parsenextc;                /* copy of parsefile->nextc */
 
 struct strpush {
        struct strpush *prev;   /* preceding string on stack */
@@ -586,416 +549,85 @@ struct parsefile {
        struct strpush basestrpush; /* so pushing one is fast */
 };
 
-struct stackmark {
-       struct stack_block *stackp;
-       char *stacknxt;
-       int stacknleft;
-       struct stackmark *marknext;
-};
-
-struct shparam {
-       int nparam;             /* # of positional parameters (without $0) */
-       unsigned char malloc;   /* if parameter list dynamically allocated */
-       char **p;               /* parameter list */
-       int optind;             /* next parameter to be processed by getopts */
-       int optoff;             /* used by getopts */
-};
-
-/*
- * When commands are first encountered, they are entered in a hash table.
- * This ensures that a full path search will not have to be done for them
- * on each invocation.
- *
- * We should investigate converting to a linear search, even though that
- * would make the command name "hash" a misnomer.
- */
-#define CMDTABLESIZE 31         /* should be prime */
-#define ARB 1                   /* actual size determined at run time */
-
-
-
-struct tblentry {
-       struct tblentry *next;  /* next entry in hash chain */
-       union param param;      /* definition of builtin function */
-       short cmdtype;          /* index identifying command */
-       char rehash;            /* if set, cd done since entry created */
-       char cmdname[ARB];      /* name of command */
-};
-
+static struct parsefile basepf;         /* top level input file */
+#define basebuf bb_common_bufsiz1       /* buffer for top level input file */
+static struct parsefile *parsefile = &basepf;  /* current input file */
 
-static struct tblentry *cmdtable[CMDTABLESIZE];
-static int builtinloc = -1;             /* index in path of %builtin, or -1 */
-static int exerrno = 0;                 /* Last exec error */
 
+static int tokpushback;                 /* last token pushed back */
+#define NEOF ((union node *)&tokpushback)
+static int parsebackquote;             /* nonzero if we are inside backquotes */
+static int doprompt;                   /* if set, prompt the user */
+static int needprompt;                 /* true if interactive and at start of line */
+static int lasttoken;                  /* last token read */
+static char *wordtext;                 /* text of last word returned by readtoken */
+static int checkkwd;
+static struct nodelist *backquotelist;
+static union node *redirnode;
+static struct heredoc *heredoc;
+static int quoteflag;                  /* set if (part of) last token was quoted */
+static int startlinno;                 /* line # where last token started */
 
-static void tryexec (char *, char **, char **);
-static void printentry (struct tblentry *, int);
-static void clearcmdentry (int);
-static struct tblentry *cmdlookup (const char *, int);
-static void delete_cmd_entry (void);
-static int path_change (const char *, int *);
+static union node *parsecmd(int);
+static void fixredir(union node *, const char *, int);
+static const char *const *findkwd(const char *);
+static char *endofname(const char *);
 
+/*      shell.h   */
 
-static void flushall (void);
-static void out2fmt (const char *, ...)
-    __attribute__((__format__(__printf__,1,2)));
-static int xwrite (int, const char *, int);
+typedef void *pointer;
 
-static inline void outstr (const char *p, FILE *file) { fputs(p, file); }
-static void out1str(const char *p) { outstr(p, stdout); }
-static void out2str(const char *p) { outstr(p, stderr); }
+static char nullstr[1];                /* zero length string */
+static const char spcstr[] = " ";
+static const char snlfmt[] = "%s\n";
+static const char dolatstr[] = { CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0' };
+static const char illnum[] = "Illegal number: %s";
+static const char homestr[] = "HOME";
 
-#ifndef CONFIG_ASH_OPTIMIZE_FOR_SIZE
-#define out2c(c)        putc((c), stderr)
+#ifdef DEBUG
+#define TRACE(param)    trace param
+#define TRACEV(param)   tracev param
 #else
-static void out2c(int c)           { putc(c, stderr); }
-#endif
-
-
-#ifdef CONFIG_ASH_OPTIMIZE_FOR_SIZE
-#define USE_SIT_FUNCTION
+#define TRACE(param)
+#define TRACEV(param)
 #endif
 
-/* number syntax index */
-#define  BASESYNTAX  0                  /* not in quotes */
-#define  DQSYNTAX    1                  /* in double quotes */
-#define  SQSYNTAX    2                  /* in single quotes */
-#define  ARISYNTAX   3                  /* in arithmetic */
-
-static const char S_I_T[][4] = {
-  /*  0 */  { CSPCL,    CIGN,      CIGN,      CIGN     },   /* PEOA */
-  /*  1 */  { CSPCL,    CWORD,     CWORD,     CWORD    },   /* ' ' */
-  /*  2 */  { CNL,      CNL,       CNL,       CNL      },   /* \n */
-  /*  3 */  { CWORD,    CCTL,      CCTL,      CWORD    },   /* !*-/:=?[]~ */
-  /*  4 */  { CDQUOTE,  CENDQUOTE, CWORD,     CDQUOTE  },   /* '"' */
-  /*  5 */  { CVAR,     CVAR,      CWORD,     CVAR     },   /* $ */
-  /*  6 */  { CSQUOTE,  CWORD,     CENDQUOTE, CSQUOTE  },   /* "'" */
-  /*  7 */  { CSPCL,    CWORD,     CWORD,     CLP      },   /* ( */
-  /*  8 */  { CSPCL,    CWORD,     CWORD,     CRP      },   /* ) */
-  /*  9 */  { CBACK,    CBACK,     CCTL,      CBACK    },   /* \ */
-  /* 10 */  { CBQUOTE,  CBQUOTE,   CWORD,     CBQUOTE  },   /* ` */
-  /* 11 */  { CENDVAR,  CENDVAR,   CWORD,     CENDVAR  },   /* } */
-#ifndef USE_SIT_FUNCTION
-  /* 12 */  { CENDFILE, CENDFILE,  CENDFILE,  CENDFILE },   /* PEOF */
-  /* 13 */  { CWORD,    CWORD,     CWORD,     CWORD    },   /* 0-9A-Za-z */
-  /* 14 */  { CCTL,     CCTL,      CCTL,      CCTL     }    /* CTLESC ... */
+#if !defined(__GNUC__) || (__GNUC__ == 2 && __GNUC_MINOR__ < 96)
+#define __builtin_expect(x, expected_value) (x)
 #endif
-};
-
-#ifdef USE_SIT_FUNCTION
-
-#define U_C(c) ((unsigned char)(c))
-
-static int SIT(int c, int syntax)
-{
-       static const char spec_symbls[]="\t\n !\"$&'()*-/:;<=>?[\\]`|}~";
-       static const char syntax_index_table [] = {
-                               1, 2, 1, 3, 4, 5, 1, 6, /* "\t\n !\"$&'" */
-                               7, 8, 3, 3, 3, 3, 1, 1, /* "()*-/:;<" */
-                               3, 1, 3, 3, 9, 3,10, 1, /* "=>?[\\]`|" */
-                               11,3 }; /* "}~" */
-       const char *s;
-       int indx;
-
-       if(c==PEOF)             /* 2^8+2 */
-               return CENDFILE;
-       if(c==PEOA)             /* 2^8+1 */
-               indx = 0;
-        else if(U_C(c)>=U_C(CTLESC) && U_C(c)<=U_C(CTLQUOTEMARK))
-               return CCTL;
-        else {
-               s = strchr(spec_symbls, c);
-               if(s==0)
-                       return CWORD;
-               indx = syntax_index_table[(s-spec_symbls)];
-       }
-       return S_I_T[indx][syntax];
-}
-
-#else  /* USE_SIT_FUNCTION */
-
-#define SIT(c, syntax) S_I_T[(int)syntax_index_table[((int)c)+SYNBASE]][syntax]
-
-#define CSPCL_CIGN_CIGN_CIGN                           0
-#define CSPCL_CWORD_CWORD_CWORD                        1
-#define CNL_CNL_CNL_CNL                                2
-#define CWORD_CCTL_CCTL_CWORD                          3
-#define CDQUOTE_CENDQUOTE_CWORD_CDQUOTE                4
-#define CVAR_CVAR_CWORD_CVAR                           5
-#define CSQUOTE_CWORD_CENDQUOTE_CSQUOTE                6
-#define CSPCL_CWORD_CWORD_CLP                          7
-#define CSPCL_CWORD_CWORD_CRP                          8
-#define CBACK_CBACK_CCTL_CBACK                         9
-#define CBQUOTE_CBQUOTE_CWORD_CBQUOTE                 10
-#define CENDVAR_CENDVAR_CWORD_CENDVAR                 11
-#define CENDFILE_CENDFILE_CENDFILE_CENDFILE           12
-#define CWORD_CWORD_CWORD_CWORD                       13
-#define CCTL_CCTL_CCTL_CCTL                           14
 
-static const char syntax_index_table[258] = {
-                /* BASESYNTAX_DQSYNTAX_SQSYNTAX_ARISYNTAX */
-  /*   0  -130 PEOF */  CENDFILE_CENDFILE_CENDFILE_CENDFILE,
-  /*   1  -129 PEOA */  CSPCL_CIGN_CIGN_CIGN,
-  /*   2  -128 0xff */  CWORD_CWORD_CWORD_CWORD,
-  /*   3  -127      */  CCTL_CCTL_CCTL_CCTL,    /* CTLQUOTEMARK */
-  /*   4  -126      */  CCTL_CCTL_CCTL_CCTL,
-  /*   5  -125      */  CCTL_CCTL_CCTL_CCTL,
-  /*   6  -124      */  CCTL_CCTL_CCTL_CCTL,
-  /*   7  -123      */  CCTL_CCTL_CCTL_CCTL,
-  /*   8  -122      */  CCTL_CCTL_CCTL_CCTL,
-  /*   9  -121      */  CCTL_CCTL_CCTL_CCTL,
-  /*  10  -120      */  CCTL_CCTL_CCTL_CCTL,    /* CTLESC */
-  /*  11  -119      */  CWORD_CWORD_CWORD_CWORD,
-  /*  12  -118      */  CWORD_CWORD_CWORD_CWORD,
-  /*  13  -117      */  CWORD_CWORD_CWORD_CWORD,
-  /*  14  -116      */  CWORD_CWORD_CWORD_CWORD,
-  /*  15  -115      */  CWORD_CWORD_CWORD_CWORD,
-  /*  16  -114      */  CWORD_CWORD_CWORD_CWORD,
-  /*  17  -113      */  CWORD_CWORD_CWORD_CWORD,
-  /*  18  -112      */  CWORD_CWORD_CWORD_CWORD,
-  /*  19  -111      */  CWORD_CWORD_CWORD_CWORD,
-  /*  20  -110      */  CWORD_CWORD_CWORD_CWORD,
-  /*  21  -109      */  CWORD_CWORD_CWORD_CWORD,
-  /*  22  -108      */  CWORD_CWORD_CWORD_CWORD,
-  /*  23  -107      */  CWORD_CWORD_CWORD_CWORD,
-  /*  24  -106      */  CWORD_CWORD_CWORD_CWORD,
-  /*  25  -105      */  CWORD_CWORD_CWORD_CWORD,
-  /*  26  -104      */  CWORD_CWORD_CWORD_CWORD,
-  /*  27  -103      */  CWORD_CWORD_CWORD_CWORD,
-  /*  28  -102      */  CWORD_CWORD_CWORD_CWORD,
-  /*  29  -101      */  CWORD_CWORD_CWORD_CWORD,
-  /*  30  -100      */  CWORD_CWORD_CWORD_CWORD,
-  /*  31   -99      */  CWORD_CWORD_CWORD_CWORD,
-  /*  32   -98      */  CWORD_CWORD_CWORD_CWORD,
-  /*  33   -97      */  CWORD_CWORD_CWORD_CWORD,
-  /*  34   -96      */  CWORD_CWORD_CWORD_CWORD,
-  /*  35   -95      */  CWORD_CWORD_CWORD_CWORD,
-  /*  36   -94      */  CWORD_CWORD_CWORD_CWORD,
-  /*  37   -93      */  CWORD_CWORD_CWORD_CWORD,
-  /*  38   -92      */  CWORD_CWORD_CWORD_CWORD,
-  /*  39   -91      */  CWORD_CWORD_CWORD_CWORD,
-  /*  40   -90      */  CWORD_CWORD_CWORD_CWORD,
-  /*  41   -89      */  CWORD_CWORD_CWORD_CWORD,
-  /*  42   -88      */  CWORD_CWORD_CWORD_CWORD,
-  /*  43   -87      */  CWORD_CWORD_CWORD_CWORD,
-  /*  44   -86      */  CWORD_CWORD_CWORD_CWORD,
-  /*  45   -85      */  CWORD_CWORD_CWORD_CWORD,
-  /*  46   -84      */  CWORD_CWORD_CWORD_CWORD,
-  /*  47   -83      */  CWORD_CWORD_CWORD_CWORD,
-  /*  48   -82      */  CWORD_CWORD_CWORD_CWORD,
-  /*  49   -81      */  CWORD_CWORD_CWORD_CWORD,
-  /*  50   -80      */  CWORD_CWORD_CWORD_CWORD,
-  /*  51   -79      */  CWORD_CWORD_CWORD_CWORD,
-  /*  52   -78      */  CWORD_CWORD_CWORD_CWORD,
-  /*  53   -77      */  CWORD_CWORD_CWORD_CWORD,
-  /*  54   -76      */  CWORD_CWORD_CWORD_CWORD,
-  /*  55   -75      */  CWORD_CWORD_CWORD_CWORD,
-  /*  56   -74      */  CWORD_CWORD_CWORD_CWORD,
-  /*  57   -73      */  CWORD_CWORD_CWORD_CWORD,
-  /*  58   -72      */  CWORD_CWORD_CWORD_CWORD,
-  /*  59   -71      */  CWORD_CWORD_CWORD_CWORD,
-  /*  60   -70      */  CWORD_CWORD_CWORD_CWORD,
-  /*  61   -69      */  CWORD_CWORD_CWORD_CWORD,
-  /*  62   -68      */  CWORD_CWORD_CWORD_CWORD,
-  /*  63   -67      */  CWORD_CWORD_CWORD_CWORD,
-  /*  64   -66      */  CWORD_CWORD_CWORD_CWORD,
-  /*  65   -65      */  CWORD_CWORD_CWORD_CWORD,
-  /*  66   -64      */  CWORD_CWORD_CWORD_CWORD,
-  /*  67   -63      */  CWORD_CWORD_CWORD_CWORD,
-  /*  68   -62      */  CWORD_CWORD_CWORD_CWORD,
-  /*  69   -61      */  CWORD_CWORD_CWORD_CWORD,
-  /*  70   -60      */  CWORD_CWORD_CWORD_CWORD,
-  /*  71   -59      */  CWORD_CWORD_CWORD_CWORD,
-  /*  72   -58      */  CWORD_CWORD_CWORD_CWORD,
-  /*  73   -57      */  CWORD_CWORD_CWORD_CWORD,
-  /*  74   -56      */  CWORD_CWORD_CWORD_CWORD,
-  /*  75   -55      */  CWORD_CWORD_CWORD_CWORD,
-  /*  76   -54      */  CWORD_CWORD_CWORD_CWORD,
-  /*  77   -53      */  CWORD_CWORD_CWORD_CWORD,
-  /*  78   -52      */  CWORD_CWORD_CWORD_CWORD,
-  /*  79   -51      */  CWORD_CWORD_CWORD_CWORD,
-  /*  80   -50      */  CWORD_CWORD_CWORD_CWORD,
-  /*  81   -49      */  CWORD_CWORD_CWORD_CWORD,
-  /*  82   -48      */  CWORD_CWORD_CWORD_CWORD,
-  /*  83   -47      */  CWORD_CWORD_CWORD_CWORD,
-  /*  84   -46      */  CWORD_CWORD_CWORD_CWORD,
-  /*  85   -45      */  CWORD_CWORD_CWORD_CWORD,
-  /*  86   -44      */  CWORD_CWORD_CWORD_CWORD,
-  /*  87   -43      */  CWORD_CWORD_CWORD_CWORD,
-  /*  88   -42      */  CWORD_CWORD_CWORD_CWORD,
-  /*  89   -41      */  CWORD_CWORD_CWORD_CWORD,
-  /*  90   -40      */  CWORD_CWORD_CWORD_CWORD,
-  /*  91   -39      */  CWORD_CWORD_CWORD_CWORD,
-  /*  92   -38      */  CWORD_CWORD_CWORD_CWORD,
-  /*  93   -37      */  CWORD_CWORD_CWORD_CWORD,
-  /*  94   -36      */  CWORD_CWORD_CWORD_CWORD,
-  /*  95   -35      */  CWORD_CWORD_CWORD_CWORD,
-  /*  96   -34      */  CWORD_CWORD_CWORD_CWORD,
-  /*  97   -33      */  CWORD_CWORD_CWORD_CWORD,
-  /*  98   -32      */  CWORD_CWORD_CWORD_CWORD,
-  /*  99   -31      */  CWORD_CWORD_CWORD_CWORD,
-  /* 100   -30      */  CWORD_CWORD_CWORD_CWORD,
-  /* 101   -29      */  CWORD_CWORD_CWORD_CWORD,
-  /* 102   -28      */  CWORD_CWORD_CWORD_CWORD,
-  /* 103   -27      */  CWORD_CWORD_CWORD_CWORD,
-  /* 104   -26      */  CWORD_CWORD_CWORD_CWORD,
-  /* 105   -25      */  CWORD_CWORD_CWORD_CWORD,
-  /* 106   -24      */  CWORD_CWORD_CWORD_CWORD,
-  /* 107   -23      */  CWORD_CWORD_CWORD_CWORD,
-  /* 108   -22      */  CWORD_CWORD_CWORD_CWORD,
-  /* 109   -21      */  CWORD_CWORD_CWORD_CWORD,
-  /* 110   -20      */  CWORD_CWORD_CWORD_CWORD,
-  /* 111   -19      */  CWORD_CWORD_CWORD_CWORD,
-  /* 112   -18      */  CWORD_CWORD_CWORD_CWORD,
-  /* 113   -17      */  CWORD_CWORD_CWORD_CWORD,
-  /* 114   -16      */  CWORD_CWORD_CWORD_CWORD,
-  /* 115   -15      */  CWORD_CWORD_CWORD_CWORD,
-  /* 116   -14      */  CWORD_CWORD_CWORD_CWORD,
-  /* 117   -13      */  CWORD_CWORD_CWORD_CWORD,
-  /* 118   -12      */  CWORD_CWORD_CWORD_CWORD,
-  /* 119   -11      */  CWORD_CWORD_CWORD_CWORD,
-  /* 120   -10      */  CWORD_CWORD_CWORD_CWORD,
-  /* 121    -9      */  CWORD_CWORD_CWORD_CWORD,
-  /* 122    -8      */  CWORD_CWORD_CWORD_CWORD,
-  /* 123    -7      */  CWORD_CWORD_CWORD_CWORD,
-  /* 124    -6      */  CWORD_CWORD_CWORD_CWORD,
-  /* 125    -5      */  CWORD_CWORD_CWORD_CWORD,
-  /* 126    -4      */  CWORD_CWORD_CWORD_CWORD,
-  /* 127    -3      */  CWORD_CWORD_CWORD_CWORD,
-  /* 128    -2      */  CWORD_CWORD_CWORD_CWORD,
-  /* 129    -1      */  CWORD_CWORD_CWORD_CWORD,
-  /* 130     0      */  CWORD_CWORD_CWORD_CWORD,
-  /* 131     1      */  CWORD_CWORD_CWORD_CWORD,
-  /* 132     2      */  CWORD_CWORD_CWORD_CWORD,
-  /* 133     3      */  CWORD_CWORD_CWORD_CWORD,
-  /* 134     4      */  CWORD_CWORD_CWORD_CWORD,
-  /* 135     5      */  CWORD_CWORD_CWORD_CWORD,
-  /* 136     6      */  CWORD_CWORD_CWORD_CWORD,
-  /* 137     7      */  CWORD_CWORD_CWORD_CWORD,
-  /* 138     8      */  CWORD_CWORD_CWORD_CWORD,
-  /* 139     9 "\t" */  CSPCL_CWORD_CWORD_CWORD,
-  /* 140    10 "\n" */  CNL_CNL_CNL_CNL,
-  /* 141    11      */  CWORD_CWORD_CWORD_CWORD,
-  /* 142    12      */  CWORD_CWORD_CWORD_CWORD,
-  /* 143    13      */  CWORD_CWORD_CWORD_CWORD,
-  /* 144    14      */  CWORD_CWORD_CWORD_CWORD,
-  /* 145    15      */  CWORD_CWORD_CWORD_CWORD,
-  /* 146    16      */  CWORD_CWORD_CWORD_CWORD,
-  /* 147    17      */  CWORD_CWORD_CWORD_CWORD,
-  /* 148    18      */  CWORD_CWORD_CWORD_CWORD,
-  /* 149    19      */  CWORD_CWORD_CWORD_CWORD,
-  /* 150    20      */  CWORD_CWORD_CWORD_CWORD,
-  /* 151    21      */  CWORD_CWORD_CWORD_CWORD,
-  /* 152    22      */  CWORD_CWORD_CWORD_CWORD,
-  /* 153    23      */  CWORD_CWORD_CWORD_CWORD,
-  /* 154    24      */  CWORD_CWORD_CWORD_CWORD,
-  /* 155    25      */  CWORD_CWORD_CWORD_CWORD,
-  /* 156    26      */  CWORD_CWORD_CWORD_CWORD,
-  /* 157    27      */  CWORD_CWORD_CWORD_CWORD,
-  /* 158    28      */  CWORD_CWORD_CWORD_CWORD,
-  /* 159    29      */  CWORD_CWORD_CWORD_CWORD,
-  /* 160    30      */  CWORD_CWORD_CWORD_CWORD,
-  /* 161    31      */  CWORD_CWORD_CWORD_CWORD,
-  /* 162    32  " " */  CSPCL_CWORD_CWORD_CWORD,
-  /* 163    33  "!" */  CWORD_CCTL_CCTL_CWORD,
-  /* 164    34  """ */  CDQUOTE_CENDQUOTE_CWORD_CDQUOTE,
-  /* 165    35  "#" */  CWORD_CWORD_CWORD_CWORD,
-  /* 166    36  "$" */  CVAR_CVAR_CWORD_CVAR,
-  /* 167    37  "%" */  CWORD_CWORD_CWORD_CWORD,
-  /* 168    38  "&" */  CSPCL_CWORD_CWORD_CWORD,
-  /* 169    39  "'" */  CSQUOTE_CWORD_CENDQUOTE_CSQUOTE,
-  /* 170    40  "(" */  CSPCL_CWORD_CWORD_CLP,
-  /* 171    41  ")" */  CSPCL_CWORD_CWORD_CRP,
-  /* 172    42  "*" */  CWORD_CCTL_CCTL_CWORD,
-  /* 173    43  "+" */  CWORD_CWORD_CWORD_CWORD,
-  /* 174    44  "," */  CWORD_CWORD_CWORD_CWORD,
-  /* 175    45  "-" */  CWORD_CCTL_CCTL_CWORD,
-  /* 176    46  "." */  CWORD_CWORD_CWORD_CWORD,
-  /* 177    47  "/" */  CWORD_CCTL_CCTL_CWORD,
-  /* 178    48  "0" */  CWORD_CWORD_CWORD_CWORD,
-  /* 179    49  "1" */  CWORD_CWORD_CWORD_CWORD,
-  /* 180    50  "2" */  CWORD_CWORD_CWORD_CWORD,
-  /* 181    51  "3" */  CWORD_CWORD_CWORD_CWORD,
-  /* 182    52  "4" */  CWORD_CWORD_CWORD_CWORD,
-  /* 183    53  "5" */  CWORD_CWORD_CWORD_CWORD,
-  /* 184    54  "6" */  CWORD_CWORD_CWORD_CWORD,
-  /* 185    55  "7" */  CWORD_CWORD_CWORD_CWORD,
-  /* 186    56  "8" */  CWORD_CWORD_CWORD_CWORD,
-  /* 187    57  "9" */  CWORD_CWORD_CWORD_CWORD,
-  /* 188    58  ":" */  CWORD_CCTL_CCTL_CWORD,
-  /* 189    59  ";" */  CSPCL_CWORD_CWORD_CWORD,
-  /* 190    60  "<" */  CSPCL_CWORD_CWORD_CWORD,
-  /* 191    61  "=" */  CWORD_CCTL_CCTL_CWORD,
-  /* 192    62  ">" */  CSPCL_CWORD_CWORD_CWORD,
-  /* 193    63  "?" */  CWORD_CCTL_CCTL_CWORD,
-  /* 194    64  "@" */  CWORD_CWORD_CWORD_CWORD,
-  /* 195    65  "A" */  CWORD_CWORD_CWORD_CWORD,
-  /* 196    66  "B" */  CWORD_CWORD_CWORD_CWORD,
-  /* 197    67  "C" */  CWORD_CWORD_CWORD_CWORD,
-  /* 198    68  "D" */  CWORD_CWORD_CWORD_CWORD,
-  /* 199    69  "E" */  CWORD_CWORD_CWORD_CWORD,
-  /* 200    70  "F" */  CWORD_CWORD_CWORD_CWORD,
-  /* 201    71  "G" */  CWORD_CWORD_CWORD_CWORD,
-  /* 202    72  "H" */  CWORD_CWORD_CWORD_CWORD,
-  /* 203    73  "I" */  CWORD_CWORD_CWORD_CWORD,
-  /* 204    74  "J" */  CWORD_CWORD_CWORD_CWORD,
-  /* 205    75  "K" */  CWORD_CWORD_CWORD_CWORD,
-  /* 206    76  "L" */  CWORD_CWORD_CWORD_CWORD,
-  /* 207    77  "M" */  CWORD_CWORD_CWORD_CWORD,
-  /* 208    78  "N" */  CWORD_CWORD_CWORD_CWORD,
-  /* 209    79  "O" */  CWORD_CWORD_CWORD_CWORD,
-  /* 210    80  "P" */  CWORD_CWORD_CWORD_CWORD,
-  /* 211    81  "Q" */  CWORD_CWORD_CWORD_CWORD,
-  /* 212    82  "R" */  CWORD_CWORD_CWORD_CWORD,
-  /* 213    83  "S" */  CWORD_CWORD_CWORD_CWORD,
-  /* 214    84  "T" */  CWORD_CWORD_CWORD_CWORD,
-  /* 215    85  "U" */  CWORD_CWORD_CWORD_CWORD,
-  /* 216    86  "V" */  CWORD_CWORD_CWORD_CWORD,
-  /* 217    87  "W" */  CWORD_CWORD_CWORD_CWORD,
-  /* 218    88  "X" */  CWORD_CWORD_CWORD_CWORD,
-  /* 219    89  "Y" */  CWORD_CWORD_CWORD_CWORD,
-  /* 220    90  "Z" */  CWORD_CWORD_CWORD_CWORD,
-  /* 221    91  "[" */  CWORD_CCTL_CCTL_CWORD,
-  /* 222    92  "\" */  CBACK_CBACK_CCTL_CBACK,
-  /* 223    93  "]" */  CWORD_CCTL_CCTL_CWORD,
-  /* 224    94  "^" */  CWORD_CWORD_CWORD_CWORD,
-  /* 225    95  "_" */  CWORD_CWORD_CWORD_CWORD,
-  /* 226    96  "`" */  CBQUOTE_CBQUOTE_CWORD_CBQUOTE,
-  /* 227    97  "a" */  CWORD_CWORD_CWORD_CWORD,
-  /* 228    98  "b" */  CWORD_CWORD_CWORD_CWORD,
-  /* 229    99  "c" */  CWORD_CWORD_CWORD_CWORD,
-  /* 230   100  "d" */  CWORD_CWORD_CWORD_CWORD,
-  /* 231   101  "e" */  CWORD_CWORD_CWORD_CWORD,
-  /* 232   102  "f" */  CWORD_CWORD_CWORD_CWORD,
-  /* 233   103  "g" */  CWORD_CWORD_CWORD_CWORD,
-  /* 234   104  "h" */  CWORD_CWORD_CWORD_CWORD,
-  /* 235   105  "i" */  CWORD_CWORD_CWORD_CWORD,
-  /* 236   106  "j" */  CWORD_CWORD_CWORD_CWORD,
-  /* 237   107  "k" */  CWORD_CWORD_CWORD_CWORD,
-  /* 238   108  "l" */  CWORD_CWORD_CWORD_CWORD,
-  /* 239   109  "m" */  CWORD_CWORD_CWORD_CWORD,
-  /* 240   110  "n" */  CWORD_CWORD_CWORD_CWORD,
-  /* 241   111  "o" */  CWORD_CWORD_CWORD_CWORD,
-  /* 242   112  "p" */  CWORD_CWORD_CWORD_CWORD,
-  /* 243   113  "q" */  CWORD_CWORD_CWORD_CWORD,
-  /* 244   114  "r" */  CWORD_CWORD_CWORD_CWORD,
-  /* 245   115  "s" */  CWORD_CWORD_CWORD_CWORD,
-  /* 246   116  "t" */  CWORD_CWORD_CWORD_CWORD,
-  /* 247   117  "u" */  CWORD_CWORD_CWORD_CWORD,
-  /* 248   118  "v" */  CWORD_CWORD_CWORD_CWORD,
-  /* 249   119  "w" */  CWORD_CWORD_CWORD_CWORD,
-  /* 250   120  "x" */  CWORD_CWORD_CWORD_CWORD,
-  /* 251   121  "y" */  CWORD_CWORD_CWORD_CWORD,
-  /* 252   122  "z" */  CWORD_CWORD_CWORD_CWORD,
-  /* 253   123  "{" */  CWORD_CWORD_CWORD_CWORD,
-  /* 254   124  "|" */  CSPCL_CWORD_CWORD_CWORD,
-  /* 255   125  "}" */  CENDVAR_CENDVAR_CWORD_CENDVAR,
-  /* 256   126  "~" */  CWORD_CCTL_CCTL_CWORD,
-  /* 257   127      */  CWORD_CWORD_CWORD_CWORD,
-};
+#define xlikely(x)       __builtin_expect((x),1)
 
-#endif  /* USE_SIT_FUNCTION */
 
+#define TEOF 0
+#define TNL 1
+#define TREDIR 2
+#define TWORD 3
+#define TSEMI 4
+#define TBACKGND 5
+#define TAND 6
+#define TOR 7
+#define TPIPE 8
+#define TLP 9
+#define TRP 10
+#define TENDCASE 11
+#define TENDBQUOTE 12
+#define TNOT 13
+#define TCASE 14
+#define TDO 15
+#define TDONE 16
+#define TELIF 17
+#define TELSE 18
+#define TESAC 19
+#define TFI 20
+#define TFOR 21
+#define TIF 22
+#define TIN 23
+#define TTHEN 24
+#define TUNTIL 25
+#define TWHILE 26
+#define TBEGIN 27
+#define TEND 28
 
 /* first char is indicating which tokens mark the end of a list */
 static const char *const tokname_array[] = {
@@ -1003,7 +635,6 @@ static const char *const tokname_array[] = {
        "\0newline",
        "\0redirection",
        "\0word",
-       "\0assignment",
        "\0;",
        "\0&",
        "\0&&",
@@ -1013,7 +644,7 @@ static const char *const tokname_array[] = {
        "\1)",
        "\1;;",
        "\1`",
-#define KWDOFFSET 14
+#define KWDOFFSET 13
        /* the following are keywords */
        "\0!",
        "\0case",
@@ -1037,162 +668,836 @@ static const char *tokname(int tok)
 {
        static char buf[16];
 
-       if(tok>=TSEMI)
+       if (tok >= TSEMI)
                buf[0] = '"';
-       sprintf(buf+(tok>=TSEMI), "%s%c",
-                       tokname_array[tok]+1, (tok>=TSEMI ? '"' : 0));
+       sprintf(buf + (tok >= TSEMI), "%s%c",
+                       tokname_array[tok] + 1, (tok >= TSEMI ? '"' : 0));
        return buf;
 }
 
-static int plinno = 1;          /* input line number */
-
-static int parselleft;          /* copy of parsefile->lleft */
-
-static struct parsefile basepf; /* top level input file */
-static char basebuf[BUFSIZ];    /* buffer for top level input file */
-static struct parsefile *parsefile = &basepf;  /* current input file */
+/*      machdep.h    */
 
 /*
- * NEOF is returned by parsecmd when it encounters an end of file.  It
- * must be distinct from NULL, so we use the address of a variable that
- * happens to be handy.
+ * Most machines require the value returned from malloc to be aligned
+ * in some way.  The following macro will get this right on many machines.
  */
 
-static int tokpushback;         /* last token pushed back */
-#define NEOF ((union node *)&tokpushback)
-static int checkkwd;            /* 1 == check for kwds, 2 == also eat newlines */
-
+#define SHELL_SIZE (sizeof(union {int i; char *cp; double d; }) - 1)
+/*
+ * It appears that grabstackstr() will barf with such alignments
+ * because stalloc() will return a string allocated in a new stackblock.
+ */
+#define SHELL_ALIGN(nbytes) (((nbytes) + SHELL_SIZE) & ~SHELL_SIZE)
 
-static void error (const char *, ...) __attribute__((__noreturn__));
-static void exerror (int, const char *, ...) __attribute__((__noreturn__));
-static void shellexec (char **, char **, const char *, int)
-    __attribute__((noreturn));
-static void exitshell (int) __attribute__((noreturn));
+/*
+ * This file was generated by the mksyntax program.
+ */
 
-static int  goodname(const char *);
-static void ignoresig (int);
-static void onsig (int);
-static void dotrap (void);
-static int  decode_signal (const char *, int);
 
-static void shprocvar(void);
-static void deletefuncs(void);
-static void setparam (char **);
-static void freeparam (volatile struct shparam *);
+/* Syntax classes */
+#define CWORD 0                 /* character is nothing special */
+#define CNL 1                   /* newline character */
+#define CBACK 2                 /* a backslash character */
+#define CSQUOTE 3               /* single quote */
+#define CDQUOTE 4               /* double quote */
+#define CENDQUOTE 5             /* a terminating quote */
+#define CBQUOTE 6               /* backwards single quote */
+#define CVAR 7                  /* a dollar sign */
+#define CENDVAR 8               /* a '}' character */
+#define CLP 9                   /* a left paren in arithmetic */
+#define CRP 10                  /* a right paren in arithmetic */
+#define CENDFILE 11             /* end of file */
+#define CCTL 12                 /* like CWORD, except it must be escaped */
+#define CSPCL 13                /* these terminate a word */
+#define CIGN 14                 /* character should be ignored */
 
-static void find_command (const char *, struct cmdentry *, int, const char *);
+#ifdef CONFIG_ASH_ALIAS
+#define SYNBASE 130
+#define PEOF -130
+#define PEOA -129
+#define PEOA_OR_PEOF PEOA
+#else
+#define SYNBASE 129
+#define PEOF -129
+#define PEOA_OR_PEOF PEOF
+#endif
 
-static inline void hashcd (void);
+#define is_digit(c)     ((unsigned)((c) - '0') <= 9)
+#define is_name(c)      ((c) == '_' || isalpha((unsigned char)(c)))
+#define is_in_name(c)   ((c) == '_' || isalnum((unsigned char)(c)))
 
-/* reasons for skipping commands (see comment on breakcmd routine) */
-#define SKIPBREAK       1
-#define SKIPCONT        2
-#define SKIPFUNC        3
-#define SKIPFILE        4
+/* C99 say: "char" declaration may be signed or unsigned default */
+#define SC2INT(chr2may_be_negative_int) (int)((signed char)chr2may_be_negative_int)
 
-/* values of cmdtype */
-#define CMDUNKNOWN -1           /* no entry in table for command */
-#define CMDNORMAL 0             /* command is an executable program */
-#define CMDBUILTIN 1            /* command is a shell builtin */
-#define CMDFUNCTION 2           /* command is a shell function */
+/*
+ * is_special(c) evaluates to 1 for c in "!#$*-0123456789?@"; 0 otherwise
+ * (assuming ascii char codes, as the original implementation did)
+ */
+#define is_special(c) \
+    ( (((unsigned int)c) - 33 < 32) \
+                        && ((0xc1ff920dUL >> (((unsigned int)c) - 33)) & 1))
 
-#define DO_ERR  1               /* find_command prints errors */
-#define DO_ABS  2               /* find_command checks absolute paths */
-#define DO_NOFUN        4       /* find_command ignores functions */
-#define DO_BRUTE        8       /* find_command ignores hash table */
+#define digit_val(c)    ((c) - '0')
 
 /*
- * Shell variables.
+ * This file was generated by the mksyntax program.
  */
 
-/* flags */
-#define VEXPORT         0x01    /* variable is exported */
-#define VREADONLY       0x02    /* variable cannot be modified */
-#define VSTRFIXED       0x04    /* variable struct is staticly allocated */
-#define VTEXTFIXED      0x08    /* text is staticly allocated */
-#define VSTACK          0x10    /* text is allocated on the stack */
-#define VUNSET          0x20    /* the variable is not set */
-#define VNOFUNC         0x40    /* don't call the callback function */
+#ifdef CONFIG_ASH_OPTIMIZE_FOR_SIZE
+#define USE_SIT_FUNCTION
+#endif
 
+/* number syntax index */
+#define  BASESYNTAX  0  /* not in quotes */
+#define  DQSYNTAX    1  /* in double quotes */
+#define  SQSYNTAX    2  /* in single quotes */
+#define  ARISYNTAX   3  /* in arithmetic */
 
-struct var {
-       struct var *next;               /* next entry in hash list */
-       int flags;                      /* flags are defined above */
-       char *text;                     /* name=value */
-       void (*func) (const char *);
-                                       /* function to be called when  */
-                                       /* the variable gets set/unset */
+#ifdef CONFIG_ASH_MATH_SUPPORT
+static const char S_I_T[][4] = {
+#ifdef CONFIG_ASH_ALIAS
+       {CSPCL, CIGN, CIGN, CIGN},              /* 0, PEOA */
+#endif
+       {CSPCL, CWORD, CWORD, CWORD},           /* 1, ' ' */
+       {CNL, CNL, CNL, CNL},                   /* 2, \n */
+       {CWORD, CCTL, CCTL, CWORD},             /* 3, !*-/:=?[]~ */
+       {CDQUOTE, CENDQUOTE, CWORD, CWORD},     /* 4, '"' */
+       {CVAR, CVAR, CWORD, CVAR},              /* 5, $ */
+       {CSQUOTE, CWORD, CENDQUOTE, CWORD},     /* 6, "'" */
+       {CSPCL, CWORD, CWORD, CLP},             /* 7, ( */
+       {CSPCL, CWORD, CWORD, CRP},             /* 8, ) */
+       {CBACK, CBACK, CCTL, CBACK},            /* 9, \ */
+       {CBQUOTE, CBQUOTE, CWORD, CBQUOTE},     /* 10, ` */
+       {CENDVAR, CENDVAR, CWORD, CENDVAR},     /* 11, } */
+#ifndef USE_SIT_FUNCTION
+       {CENDFILE, CENDFILE, CENDFILE, CENDFILE},       /* 12, PEOF */
+       {CWORD, CWORD, CWORD, CWORD},           /* 13, 0-9A-Za-z */
+       {CCTL, CCTL, CCTL, CCTL}                /* 14, CTLESC ... */
+#endif
 };
+#else
+static const char S_I_T[][3] = {
+#ifdef CONFIG_ASH_ALIAS
+       {CSPCL, CIGN, CIGN},                    /* 0, PEOA */
+#endif
+       {CSPCL, CWORD, CWORD},                  /* 1, ' ' */
+       {CNL, CNL, CNL},                        /* 2, \n */
+       {CWORD, CCTL, CCTL},                    /* 3, !*-/:=?[]~ */
+       {CDQUOTE, CENDQUOTE, CWORD},            /* 4, '"' */
+       {CVAR, CVAR, CWORD},                    /* 5, $ */
+       {CSQUOTE, CWORD, CENDQUOTE},            /* 6, "'" */
+       {CSPCL, CWORD, CWORD},                  /* 7, ( */
+       {CSPCL, CWORD, CWORD},                  /* 8, ) */
+       {CBACK, CBACK, CCTL},                   /* 9, \ */
+       {CBQUOTE, CBQUOTE, CWORD},              /* 10, ` */
+       {CENDVAR, CENDVAR, CWORD},              /* 11, } */
+#ifndef USE_SIT_FUNCTION
+       {CENDFILE, CENDFILE, CENDFILE},         /* 12, PEOF */
+       {CWORD, CWORD, CWORD},                  /* 13, 0-9A-Za-z */
+       {CCTL, CCTL, CCTL}                      /* 14, CTLESC ... */
+#endif
+};
+#endif /* CONFIG_ASH_MATH_SUPPORT */
 
-struct localvar {
-       struct localvar *next;          /* next local variable in list */
-       struct var *vp;                 /* the variable that was made local */
-       int flags;                      /* saved flags */
-       char *text;                     /* saved text */
+#ifdef USE_SIT_FUNCTION
+
+#define U_C(c) ((unsigned char)(c))
+
+static int SIT(int c, int syntax)
+{
+       static const char spec_symbls[] = "\t\n !\"$&'()*-/:;<=>?[\\]`|}~";
+#ifdef CONFIG_ASH_ALIAS
+       static const char syntax_index_table[] = {
+               1, 2, 1, 3, 4, 5, 1, 6,         /* "\t\n !\"$&'" */
+               7, 8, 3, 3, 3, 3, 1, 1,         /* "()*-/:;<" */
+               3, 1, 3, 3, 9, 3, 10, 1,        /* "=>?[\\]`|" */
+               11, 3                           /* "}~" */
+       };
+#else
+       static const char syntax_index_table[] = {
+               0, 1, 0, 2, 3, 4, 0, 5,         /* "\t\n !\"$&'" */
+               6, 7, 2, 2, 2, 2, 0, 0,         /* "()*-/:;<" */
+               2, 0, 2, 2, 8, 2, 9, 0,         /* "=>?[\\]`|" */
+               10, 2                           /* "}~" */
+       };
+#endif
+       const char *s;
+       int indx;
+
+       if (c == PEOF)          /* 2^8+2 */
+               return CENDFILE;
+#ifdef CONFIG_ASH_ALIAS
+       if (c == PEOA)          /* 2^8+1 */
+               indx = 0;
+       else
+#endif
+               if (U_C(c) >= U_C(CTLESC) && U_C(c) <= U_C(CTLQUOTEMARK))
+                       return CCTL;
+       else {
+               s = strchr(spec_symbls, c);
+               if (s == 0 || *s == 0)
+                       return CWORD;
+               indx = syntax_index_table[(s - spec_symbls)];
+       }
+       return S_I_T[indx][syntax];
+}
+
+#else   /* USE_SIT_FUNCTION */
+
+#define SIT(c, syntax) S_I_T[(int)syntax_index_table[((int)c)+SYNBASE]][syntax]
+
+#ifdef CONFIG_ASH_ALIAS
+#define CSPCL_CIGN_CIGN_CIGN                           0
+#define CSPCL_CWORD_CWORD_CWORD                        1
+#define CNL_CNL_CNL_CNL                                2
+#define CWORD_CCTL_CCTL_CWORD                          3
+#define CDQUOTE_CENDQUOTE_CWORD_CWORD                  4
+#define CVAR_CVAR_CWORD_CVAR                           5
+#define CSQUOTE_CWORD_CENDQUOTE_CWORD                  6
+#define CSPCL_CWORD_CWORD_CLP                          7
+#define CSPCL_CWORD_CWORD_CRP                          8
+#define CBACK_CBACK_CCTL_CBACK                         9
+#define CBQUOTE_CBQUOTE_CWORD_CBQUOTE                 10
+#define CENDVAR_CENDVAR_CWORD_CENDVAR                 11
+#define CENDFILE_CENDFILE_CENDFILE_CENDFILE           12
+#define CWORD_CWORD_CWORD_CWORD                       13
+#define CCTL_CCTL_CCTL_CCTL                           14
+#else
+#define CSPCL_CWORD_CWORD_CWORD                        0
+#define CNL_CNL_CNL_CNL                                1
+#define CWORD_CCTL_CCTL_CWORD                          2
+#define CDQUOTE_CENDQUOTE_CWORD_CWORD                  3
+#define CVAR_CVAR_CWORD_CVAR                           4
+#define CSQUOTE_CWORD_CENDQUOTE_CWORD                  5
+#define CSPCL_CWORD_CWORD_CLP                          6
+#define CSPCL_CWORD_CWORD_CRP                          7
+#define CBACK_CBACK_CCTL_CBACK                         8
+#define CBQUOTE_CBQUOTE_CWORD_CBQUOTE                  9
+#define CENDVAR_CENDVAR_CWORD_CENDVAR                 10
+#define CENDFILE_CENDFILE_CENDFILE_CENDFILE           11
+#define CWORD_CWORD_CWORD_CWORD                       12
+#define CCTL_CCTL_CCTL_CCTL                           13
+#endif
+
+static const char syntax_index_table[258] = {
+       /* BASESYNTAX_DQSYNTAX_SQSYNTAX_ARISYNTAX */
+       /*   0  PEOF */      CENDFILE_CENDFILE_CENDFILE_CENDFILE,
+#ifdef CONFIG_ASH_ALIAS
+       /*   1  PEOA */      CSPCL_CIGN_CIGN_CIGN,
+#endif
+       /*   2  -128 0x80 */ CWORD_CWORD_CWORD_CWORD,
+       /*   3  -127 CTLESC       */ CCTL_CCTL_CCTL_CCTL,
+       /*   4  -126 CTLVAR       */ CCTL_CCTL_CCTL_CCTL,
+       /*   5  -125 CTLENDVAR    */ CCTL_CCTL_CCTL_CCTL,
+       /*   6  -124 CTLBACKQ     */ CCTL_CCTL_CCTL_CCTL,
+       /*   7  -123 CTLQUOTE     */ CCTL_CCTL_CCTL_CCTL,
+       /*   8  -122 CTLARI       */ CCTL_CCTL_CCTL_CCTL,
+       /*   9  -121 CTLENDARI    */ CCTL_CCTL_CCTL_CCTL,
+       /*  10  -120 CTLQUOTEMARK */ CCTL_CCTL_CCTL_CCTL,
+       /*  11  -119      */ CWORD_CWORD_CWORD_CWORD,
+       /*  12  -118      */ CWORD_CWORD_CWORD_CWORD,
+       /*  13  -117      */ CWORD_CWORD_CWORD_CWORD,
+       /*  14  -116      */ CWORD_CWORD_CWORD_CWORD,
+       /*  15  -115      */ CWORD_CWORD_CWORD_CWORD,
+       /*  16  -114      */ CWORD_CWORD_CWORD_CWORD,
+       /*  17  -113      */ CWORD_CWORD_CWORD_CWORD,
+       /*  18  -112      */ CWORD_CWORD_CWORD_CWORD,
+       /*  19  -111      */ CWORD_CWORD_CWORD_CWORD,
+       /*  20  -110      */ CWORD_CWORD_CWORD_CWORD,
+       /*  21  -109      */ CWORD_CWORD_CWORD_CWORD,
+       /*  22  -108      */ CWORD_CWORD_CWORD_CWORD,
+       /*  23  -107      */ CWORD_CWORD_CWORD_CWORD,
+       /*  24  -106      */ CWORD_CWORD_CWORD_CWORD,
+       /*  25  -105      */ CWORD_CWORD_CWORD_CWORD,
+       /*  26  -104      */ CWORD_CWORD_CWORD_CWORD,
+       /*  27  -103      */ CWORD_CWORD_CWORD_CWORD,
+       /*  28  -102      */ CWORD_CWORD_CWORD_CWORD,
+       /*  29  -101      */ CWORD_CWORD_CWORD_CWORD,
+       /*  30  -100      */ CWORD_CWORD_CWORD_CWORD,
+       /*  31   -99      */ CWORD_CWORD_CWORD_CWORD,
+       /*  32   -98      */ CWORD_CWORD_CWORD_CWORD,
+       /*  33   -97      */ CWORD_CWORD_CWORD_CWORD,
+       /*  34   -96      */ CWORD_CWORD_CWORD_CWORD,
+       /*  35   -95      */ CWORD_CWORD_CWORD_CWORD,
+       /*  36   -94      */ CWORD_CWORD_CWORD_CWORD,
+       /*  37   -93      */ CWORD_CWORD_CWORD_CWORD,
+       /*  38   -92      */ CWORD_CWORD_CWORD_CWORD,
+       /*  39   -91      */ CWORD_CWORD_CWORD_CWORD,
+       /*  40   -90      */ CWORD_CWORD_CWORD_CWORD,
+       /*  41   -89      */ CWORD_CWORD_CWORD_CWORD,
+       /*  42   -88      */ CWORD_CWORD_CWORD_CWORD,
+       /*  43   -87      */ CWORD_CWORD_CWORD_CWORD,
+       /*  44   -86      */ CWORD_CWORD_CWORD_CWORD,
+       /*  45   -85      */ CWORD_CWORD_CWORD_CWORD,
+       /*  46   -84      */ CWORD_CWORD_CWORD_CWORD,
+       /*  47   -83      */ CWORD_CWORD_CWORD_CWORD,
+       /*  48   -82      */ CWORD_CWORD_CWORD_CWORD,
+       /*  49   -81      */ CWORD_CWORD_CWORD_CWORD,
+       /*  50   -80      */ CWORD_CWORD_CWORD_CWORD,
+       /*  51   -79      */ CWORD_CWORD_CWORD_CWORD,
+       /*  52   -78      */ CWORD_CWORD_CWORD_CWORD,
+       /*  53   -77      */ CWORD_CWORD_CWORD_CWORD,
+       /*  54   -76      */ CWORD_CWORD_CWORD_CWORD,
+       /*  55   -75      */ CWORD_CWORD_CWORD_CWORD,
+       /*  56   -74      */ CWORD_CWORD_CWORD_CWORD,
+       /*  57   -73      */ CWORD_CWORD_CWORD_CWORD,
+       /*  58   -72      */ CWORD_CWORD_CWORD_CWORD,
+       /*  59   -71      */ CWORD_CWORD_CWORD_CWORD,
+       /*  60   -70      */ CWORD_CWORD_CWORD_CWORD,
+       /*  61   -69      */ CWORD_CWORD_CWORD_CWORD,
+       /*  62   -68      */ CWORD_CWORD_CWORD_CWORD,
+       /*  63   -67      */ CWORD_CWORD_CWORD_CWORD,
+       /*  64   -66      */ CWORD_CWORD_CWORD_CWORD,
+       /*  65   -65      */ CWORD_CWORD_CWORD_CWORD,
+       /*  66   -64      */ CWORD_CWORD_CWORD_CWORD,
+       /*  67   -63      */ CWORD_CWORD_CWORD_CWORD,
+       /*  68   -62      */ CWORD_CWORD_CWORD_CWORD,
+       /*  69   -61      */ CWORD_CWORD_CWORD_CWORD,
+       /*  70   -60      */ CWORD_CWORD_CWORD_CWORD,
+       /*  71   -59      */ CWORD_CWORD_CWORD_CWORD,
+       /*  72   -58      */ CWORD_CWORD_CWORD_CWORD,
+       /*  73   -57      */ CWORD_CWORD_CWORD_CWORD,
+       /*  74   -56      */ CWORD_CWORD_CWORD_CWORD,
+       /*  75   -55      */ CWORD_CWORD_CWORD_CWORD,
+       /*  76   -54      */ CWORD_CWORD_CWORD_CWORD,
+       /*  77   -53      */ CWORD_CWORD_CWORD_CWORD,
+       /*  78   -52      */ CWORD_CWORD_CWORD_CWORD,
+       /*  79   -51      */ CWORD_CWORD_CWORD_CWORD,
+       /*  80   -50      */ CWORD_CWORD_CWORD_CWORD,
+       /*  81   -49      */ CWORD_CWORD_CWORD_CWORD,
+       /*  82   -48      */ CWORD_CWORD_CWORD_CWORD,
+       /*  83   -47      */ CWORD_CWORD_CWORD_CWORD,
+       /*  84   -46      */ CWORD_CWORD_CWORD_CWORD,
+       /*  85   -45      */ CWORD_CWORD_CWORD_CWORD,
+       /*  86   -44      */ CWORD_CWORD_CWORD_CWORD,
+       /*  87   -43      */ CWORD_CWORD_CWORD_CWORD,
+       /*  88   -42      */ CWORD_CWORD_CWORD_CWORD,
+       /*  89   -41      */ CWORD_CWORD_CWORD_CWORD,
+       /*  90   -40      */ CWORD_CWORD_CWORD_CWORD,
+       /*  91   -39      */ CWORD_CWORD_CWORD_CWORD,
+       /*  92   -38      */ CWORD_CWORD_CWORD_CWORD,
+       /*  93   -37      */ CWORD_CWORD_CWORD_CWORD,
+       /*  94   -36      */ CWORD_CWORD_CWORD_CWORD,
+       /*  95   -35      */ CWORD_CWORD_CWORD_CWORD,
+       /*  96   -34      */ CWORD_CWORD_CWORD_CWORD,
+       /*  97   -33      */ CWORD_CWORD_CWORD_CWORD,
+       /*  98   -32      */ CWORD_CWORD_CWORD_CWORD,
+       /*  99   -31      */ CWORD_CWORD_CWORD_CWORD,
+       /* 100   -30      */ CWORD_CWORD_CWORD_CWORD,
+       /* 101   -29      */ CWORD_CWORD_CWORD_CWORD,
+       /* 102   -28      */ CWORD_CWORD_CWORD_CWORD,
+       /* 103   -27      */ CWORD_CWORD_CWORD_CWORD,
+       /* 104   -26      */ CWORD_CWORD_CWORD_CWORD,
+       /* 105   -25      */ CWORD_CWORD_CWORD_CWORD,
+       /* 106   -24      */ CWORD_CWORD_CWORD_CWORD,
+       /* 107   -23      */ CWORD_CWORD_CWORD_CWORD,
+       /* 108   -22      */ CWORD_CWORD_CWORD_CWORD,
+       /* 109   -21      */ CWORD_CWORD_CWORD_CWORD,
+       /* 110   -20      */ CWORD_CWORD_CWORD_CWORD,
+       /* 111   -19      */ CWORD_CWORD_CWORD_CWORD,
+       /* 112   -18      */ CWORD_CWORD_CWORD_CWORD,
+       /* 113   -17      */ CWORD_CWORD_CWORD_CWORD,
+       /* 114   -16      */ CWORD_CWORD_CWORD_CWORD,
+       /* 115   -15      */ CWORD_CWORD_CWORD_CWORD,
+       /* 116   -14      */ CWORD_CWORD_CWORD_CWORD,
+       /* 117   -13      */ CWORD_CWORD_CWORD_CWORD,
+       /* 118   -12      */ CWORD_CWORD_CWORD_CWORD,
+       /* 119   -11      */ CWORD_CWORD_CWORD_CWORD,
+       /* 120   -10      */ CWORD_CWORD_CWORD_CWORD,
+       /* 121    -9      */ CWORD_CWORD_CWORD_CWORD,
+       /* 122    -8      */ CWORD_CWORD_CWORD_CWORD,
+       /* 123    -7      */ CWORD_CWORD_CWORD_CWORD,
+       /* 124    -6      */ CWORD_CWORD_CWORD_CWORD,
+       /* 125    -5      */ CWORD_CWORD_CWORD_CWORD,
+       /* 126    -4      */ CWORD_CWORD_CWORD_CWORD,
+       /* 127    -3      */ CWORD_CWORD_CWORD_CWORD,
+       /* 128    -2      */ CWORD_CWORD_CWORD_CWORD,
+       /* 129    -1      */ CWORD_CWORD_CWORD_CWORD,
+       /* 130     0      */ CWORD_CWORD_CWORD_CWORD,
+       /* 131     1      */ CWORD_CWORD_CWORD_CWORD,
+       /* 132     2      */ CWORD_CWORD_CWORD_CWORD,
+       /* 133     3      */ CWORD_CWORD_CWORD_CWORD,
+       /* 134     4      */ CWORD_CWORD_CWORD_CWORD,
+       /* 135     5      */ CWORD_CWORD_CWORD_CWORD,
+       /* 136     6      */ CWORD_CWORD_CWORD_CWORD,
+       /* 137     7      */ CWORD_CWORD_CWORD_CWORD,
+       /* 138     8      */ CWORD_CWORD_CWORD_CWORD,
+       /* 139     9 "\t" */ CSPCL_CWORD_CWORD_CWORD,
+       /* 140    10 "\n" */ CNL_CNL_CNL_CNL,
+       /* 141    11      */ CWORD_CWORD_CWORD_CWORD,
+       /* 142    12      */ CWORD_CWORD_CWORD_CWORD,
+       /* 143    13      */ CWORD_CWORD_CWORD_CWORD,
+       /* 144    14      */ CWORD_CWORD_CWORD_CWORD,
+       /* 145    15      */ CWORD_CWORD_CWORD_CWORD,
+       /* 146    16      */ CWORD_CWORD_CWORD_CWORD,
+       /* 147    17      */ CWORD_CWORD_CWORD_CWORD,
+       /* 148    18      */ CWORD_CWORD_CWORD_CWORD,
+       /* 149    19      */ CWORD_CWORD_CWORD_CWORD,
+       /* 150    20      */ CWORD_CWORD_CWORD_CWORD,
+       /* 151    21      */ CWORD_CWORD_CWORD_CWORD,
+       /* 152    22      */ CWORD_CWORD_CWORD_CWORD,
+       /* 153    23      */ CWORD_CWORD_CWORD_CWORD,
+       /* 154    24      */ CWORD_CWORD_CWORD_CWORD,
+       /* 155    25      */ CWORD_CWORD_CWORD_CWORD,
+       /* 156    26      */ CWORD_CWORD_CWORD_CWORD,
+       /* 157    27      */ CWORD_CWORD_CWORD_CWORD,
+       /* 158    28      */ CWORD_CWORD_CWORD_CWORD,
+       /* 159    29      */ CWORD_CWORD_CWORD_CWORD,
+       /* 160    30      */ CWORD_CWORD_CWORD_CWORD,
+       /* 161    31      */ CWORD_CWORD_CWORD_CWORD,
+       /* 162    32  " " */ CSPCL_CWORD_CWORD_CWORD,
+       /* 163    33  "!" */ CWORD_CCTL_CCTL_CWORD,
+       /* 164    34  """ */ CDQUOTE_CENDQUOTE_CWORD_CWORD,
+       /* 165    35  "#" */ CWORD_CWORD_CWORD_CWORD,
+       /* 166    36  "$" */ CVAR_CVAR_CWORD_CVAR,
+       /* 167    37  "%" */ CWORD_CWORD_CWORD_CWORD,
+       /* 168    38  "&" */ CSPCL_CWORD_CWORD_CWORD,
+       /* 169    39  "'" */ CSQUOTE_CWORD_CENDQUOTE_CWORD,
+       /* 170    40  "(" */ CSPCL_CWORD_CWORD_CLP,
+       /* 171    41  ")" */ CSPCL_CWORD_CWORD_CRP,
+       /* 172    42  "*" */ CWORD_CCTL_CCTL_CWORD,
+       /* 173    43  "+" */ CWORD_CWORD_CWORD_CWORD,
+       /* 174    44  "," */ CWORD_CWORD_CWORD_CWORD,
+       /* 175    45  "-" */ CWORD_CCTL_CCTL_CWORD,
+       /* 176    46  "." */ CWORD_CWORD_CWORD_CWORD,
+       /* 177    47  "/" */ CWORD_CCTL_CCTL_CWORD,
+       /* 178    48  "0" */ CWORD_CWORD_CWORD_CWORD,
+       /* 179    49  "1" */ CWORD_CWORD_CWORD_CWORD,
+       /* 180    50  "2" */ CWORD_CWORD_CWORD_CWORD,
+       /* 181    51  "3" */ CWORD_CWORD_CWORD_CWORD,
+       /* 182    52  "4" */ CWORD_CWORD_CWORD_CWORD,
+       /* 183    53  "5" */ CWORD_CWORD_CWORD_CWORD,
+       /* 184    54  "6" */ CWORD_CWORD_CWORD_CWORD,
+       /* 185    55  "7" */ CWORD_CWORD_CWORD_CWORD,
+       /* 186    56  "8" */ CWORD_CWORD_CWORD_CWORD,
+       /* 187    57  "9" */ CWORD_CWORD_CWORD_CWORD,
+       /* 188    58  ":" */ CWORD_CCTL_CCTL_CWORD,
+       /* 189    59  ";" */ CSPCL_CWORD_CWORD_CWORD,
+       /* 190    60  "<" */ CSPCL_CWORD_CWORD_CWORD,
+       /* 191    61  "=" */ CWORD_CCTL_CCTL_CWORD,
+       /* 192    62  ">" */ CSPCL_CWORD_CWORD_CWORD,
+       /* 193    63  "?" */ CWORD_CCTL_CCTL_CWORD,
+       /* 194    64  "@" */ CWORD_CWORD_CWORD_CWORD,
+       /* 195    65  "A" */ CWORD_CWORD_CWORD_CWORD,
+       /* 196    66  "B" */ CWORD_CWORD_CWORD_CWORD,
+       /* 197    67  "C" */ CWORD_CWORD_CWORD_CWORD,
+       /* 198    68  "D" */ CWORD_CWORD_CWORD_CWORD,
+       /* 199    69  "E" */ CWORD_CWORD_CWORD_CWORD,
+       /* 200    70  "F" */ CWORD_CWORD_CWORD_CWORD,
+       /* 201    71  "G" */ CWORD_CWORD_CWORD_CWORD,
+       /* 202    72  "H" */ CWORD_CWORD_CWORD_CWORD,
+       /* 203    73  "I" */ CWORD_CWORD_CWORD_CWORD,
+       /* 204    74  "J" */ CWORD_CWORD_CWORD_CWORD,
+       /* 205    75  "K" */ CWORD_CWORD_CWORD_CWORD,
+       /* 206    76  "L" */ CWORD_CWORD_CWORD_CWORD,
+       /* 207    77  "M" */ CWORD_CWORD_CWORD_CWORD,
+       /* 208    78  "N" */ CWORD_CWORD_CWORD_CWORD,
+       /* 209    79  "O" */ CWORD_CWORD_CWORD_CWORD,
+       /* 210    80  "P" */ CWORD_CWORD_CWORD_CWORD,
+       /* 211    81  "Q" */ CWORD_CWORD_CWORD_CWORD,
+       /* 212    82  "R" */ CWORD_CWORD_CWORD_CWORD,
+       /* 213    83  "S" */ CWORD_CWORD_CWORD_CWORD,
+       /* 214    84  "T" */ CWORD_CWORD_CWORD_CWORD,
+       /* 215    85  "U" */ CWORD_CWORD_CWORD_CWORD,
+       /* 216    86  "V" */ CWORD_CWORD_CWORD_CWORD,
+       /* 217    87  "W" */ CWORD_CWORD_CWORD_CWORD,
+       /* 218    88  "X" */ CWORD_CWORD_CWORD_CWORD,
+       /* 219    89  "Y" */ CWORD_CWORD_CWORD_CWORD,
+       /* 220    90  "Z" */ CWORD_CWORD_CWORD_CWORD,
+       /* 221    91  "[" */ CWORD_CCTL_CCTL_CWORD,
+       /* 222    92  "\" */ CBACK_CBACK_CCTL_CBACK,
+       /* 223    93  "]" */ CWORD_CCTL_CCTL_CWORD,
+       /* 224    94  "^" */ CWORD_CWORD_CWORD_CWORD,
+       /* 225    95  "_" */ CWORD_CWORD_CWORD_CWORD,
+       /* 226    96  "`" */ CBQUOTE_CBQUOTE_CWORD_CBQUOTE,
+       /* 227    97  "a" */ CWORD_CWORD_CWORD_CWORD,
+       /* 228    98  "b" */ CWORD_CWORD_CWORD_CWORD,
+       /* 229    99  "c" */ CWORD_CWORD_CWORD_CWORD,
+       /* 230   100  "d" */ CWORD_CWORD_CWORD_CWORD,
+       /* 231   101  "e" */ CWORD_CWORD_CWORD_CWORD,
+       /* 232   102  "f" */ CWORD_CWORD_CWORD_CWORD,
+       /* 233   103  "g" */ CWORD_CWORD_CWORD_CWORD,
+       /* 234   104  "h" */ CWORD_CWORD_CWORD_CWORD,
+       /* 235   105  "i" */ CWORD_CWORD_CWORD_CWORD,
+       /* 236   106  "j" */ CWORD_CWORD_CWORD_CWORD,
+       /* 237   107  "k" */ CWORD_CWORD_CWORD_CWORD,
+       /* 238   108  "l" */ CWORD_CWORD_CWORD_CWORD,
+       /* 239   109  "m" */ CWORD_CWORD_CWORD_CWORD,
+       /* 240   110  "n" */ CWORD_CWORD_CWORD_CWORD,
+       /* 241   111  "o" */ CWORD_CWORD_CWORD_CWORD,
+       /* 242   112  "p" */ CWORD_CWORD_CWORD_CWORD,
+       /* 243   113  "q" */ CWORD_CWORD_CWORD_CWORD,
+       /* 244   114  "r" */ CWORD_CWORD_CWORD_CWORD,
+       /* 245   115  "s" */ CWORD_CWORD_CWORD_CWORD,
+       /* 246   116  "t" */ CWORD_CWORD_CWORD_CWORD,
+       /* 247   117  "u" */ CWORD_CWORD_CWORD_CWORD,
+       /* 248   118  "v" */ CWORD_CWORD_CWORD_CWORD,
+       /* 249   119  "w" */ CWORD_CWORD_CWORD_CWORD,
+       /* 250   120  "x" */ CWORD_CWORD_CWORD_CWORD,
+       /* 251   121  "y" */ CWORD_CWORD_CWORD_CWORD,
+       /* 252   122  "z" */ CWORD_CWORD_CWORD_CWORD,
+       /* 253   123  "{" */ CWORD_CWORD_CWORD_CWORD,
+       /* 254   124  "|" */ CSPCL_CWORD_CWORD_CWORD,
+       /* 255   125  "}" */ CENDVAR_CENDVAR_CWORD_CENDVAR,
+       /* 256   126  "~" */ CWORD_CCTL_CCTL_CWORD,
+       /* 257   127      */ CWORD_CWORD_CWORD_CWORD,
 };
 
+#endif  /* USE_SIT_FUNCTION */
+
+/*      alias.c      */
 
-#if defined(__GLIBC__) && __GLIBC__ >= 2 && !defined(FNMATCH_BROKEN)
-#define rmescapes(p) _rmescapes((p), 0)
-static char *_rmescapes (char *, int);
+
+#define ATABSIZE 39
+
+static int     funcblocksize;          /* size of structures in function */
+static int     funcstringsize;         /* size of strings in node */
+static pointer funcblock;              /* block to allocate function from */
+static char   *funcstring;             /* block to allocate strings from */
+
+static const short nodesize[26] = {
+      SHELL_ALIGN(sizeof (struct ncmd)),
+      SHELL_ALIGN(sizeof (struct npipe)),
+      SHELL_ALIGN(sizeof (struct nredir)),
+      SHELL_ALIGN(sizeof (struct nredir)),
+      SHELL_ALIGN(sizeof (struct nredir)),
+      SHELL_ALIGN(sizeof (struct nbinary)),
+      SHELL_ALIGN(sizeof (struct nbinary)),
+      SHELL_ALIGN(sizeof (struct nbinary)),
+      SHELL_ALIGN(sizeof (struct nif)),
+      SHELL_ALIGN(sizeof (struct nbinary)),
+      SHELL_ALIGN(sizeof (struct nbinary)),
+      SHELL_ALIGN(sizeof (struct nfor)),
+      SHELL_ALIGN(sizeof (struct ncase)),
+      SHELL_ALIGN(sizeof (struct nclist)),
+      SHELL_ALIGN(sizeof (struct narg)),
+      SHELL_ALIGN(sizeof (struct narg)),
+      SHELL_ALIGN(sizeof (struct nfile)),
+      SHELL_ALIGN(sizeof (struct nfile)),
+      SHELL_ALIGN(sizeof (struct nfile)),
+      SHELL_ALIGN(sizeof (struct nfile)),
+      SHELL_ALIGN(sizeof (struct nfile)),
+      SHELL_ALIGN(sizeof (struct ndup)),
+      SHELL_ALIGN(sizeof (struct ndup)),
+      SHELL_ALIGN(sizeof (struct nhere)),
+      SHELL_ALIGN(sizeof (struct nhere)),
+      SHELL_ALIGN(sizeof (struct nnot)),
+};
+
+
+static void calcsize(union node *);
+static void sizenodelist(struct nodelist *);
+static union node *copynode(union node *);
+static struct nodelist *copynodelist(struct nodelist *);
+static char *nodesavestr(char *);
+
+
+static int evalstring(char *, int mask);
+union node;     /* BLETCH for ansi C */
+static void evaltree(union node *, int);
+static void evalbackcmd(union node *, struct backcmd *);
+
+static int evalskip;                   /* set if we are skipping commands */
+static int skipcount;           /* number of levels to skip */
+static int funcnest;                   /* depth of function calls */
+
+/* reasons for skipping commands (see comment on breakcmd routine) */
+#define SKIPBREAK      (1 << 0)
+#define SKIPCONT       (1 << 1)
+#define SKIPFUNC       (1 << 2)
+#define SKIPFILE       (1 << 3)
+#define SKIPEVAL       (1 << 4)
+
+/*
+ * This file was generated by the mkbuiltins program.
+ */
+
+#if JOBS
+static int bgcmd(int, char **);
+#endif
+static int breakcmd(int, char **);
+static int cdcmd(int, char **);
+#ifdef CONFIG_ASH_CMDCMD
+static int commandcmd(int, char **);
+#endif
+static int dotcmd(int, char **);
+static int evalcmd(int, char **);
+#ifdef CONFIG_ASH_BUILTIN_ECHO
+static int echocmd(int, char **);
+#endif
+#ifdef CONFIG_ASH_BUILTIN_TEST
+static int testcmd(int, char **);
+#endif
+static int execcmd(int, char **);
+static int exitcmd(int, char **);
+static int exportcmd(int, char **);
+static int falsecmd(int, char **);
+#if JOBS
+static int fgcmd(int, char **);
+#endif
+#ifdef CONFIG_ASH_GETOPTS
+static int getoptscmd(int, char **);
+#endif
+static int hashcmd(int, char **);
+#ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
+static int helpcmd(int argc, char **argv);
+#endif
+#if JOBS
+static int jobscmd(int, char **);
+#endif
+#ifdef CONFIG_ASH_MATH_SUPPORT
+static int letcmd(int, char **);
+#endif
+static int localcmd(int, char **);
+static int pwdcmd(int, char **);
+static int readcmd(int, char **);
+static int returncmd(int, char **);
+static int setcmd(int, char **);
+static int shiftcmd(int, char **);
+static int timescmd(int, char **);
+static int trapcmd(int, char **);
+static int truecmd(int, char **);
+static int typecmd(int, char **);
+static int umaskcmd(int, char **);
+static int unsetcmd(int, char **);
+static int waitcmd(int, char **);
+static int ulimitcmd(int, char **);
+#if JOBS
+static int killcmd(int, char **);
+#endif
+
+/*      mail.h        */
+
+#ifdef CONFIG_ASH_MAIL
+static void chkmail(void);
+static void changemail(const char *);
+#endif
+
+/*      exec.h    */
+
+/* values of cmdtype */
+#define CMDUNKNOWN      -1      /* no entry in table for command */
+#define CMDNORMAL       0       /* command is an executable program */
+#define CMDFUNCTION     1       /* command is a shell function */
+#define CMDBUILTIN      2       /* command is a shell builtin */
+
+struct builtincmd {
+       const char *name;
+       int (*builtin)(int, char **);
+       /* unsigned flags; */
+};
+
+
+#define COMMANDCMD (builtincmd + 5 + \
+       2 * ENABLE_ASH_BUILTIN_TEST + \
+       ENABLE_ASH_ALIAS + \
+       ENABLE_ASH_JOB_CONTROL)
+#define EXECCMD (builtincmd + 7 + \
+       2 * ENABLE_ASH_BUILTIN_TEST + \
+       ENABLE_ASH_ALIAS + \
+       ENABLE_ASH_JOB_CONTROL + \
+       ENABLE_ASH_CMDCMD + \
+       ENABLE_ASH_BUILTIN_ECHO)
+
+#define BUILTIN_NOSPEC  "0"
+#define BUILTIN_SPECIAL "1"
+#define BUILTIN_REGULAR "2"
+#define BUILTIN_SPEC_REG "3"
+#define BUILTIN_ASSIGN  "4"
+#define BUILTIN_SPEC_ASSG  "5"
+#define BUILTIN_REG_ASSG   "6"
+#define BUILTIN_SPEC_REG_ASSG   "7"
+
+#define IS_BUILTIN_SPECIAL(builtincmd) ((builtincmd)->name[0] & 1)
+#define IS_BUILTIN_REGULAR(builtincmd) ((builtincmd)->name[0] & 2)
+#define IS_BUILTIN_ASSIGN(builtincmd) ((builtincmd)->name[0] & 4)
+
+/* make sure to keep these in proper order since it is searched via bsearch() */
+static const struct builtincmd builtincmd[] = {
+       { BUILTIN_SPEC_REG      ".", dotcmd },
+       { BUILTIN_SPEC_REG      ":", truecmd },
+#ifdef CONFIG_ASH_BUILTIN_TEST
+       { BUILTIN_REGULAR       "[", testcmd },
+       { BUILTIN_REGULAR       "[[", testcmd },
+#endif
+#ifdef CONFIG_ASH_ALIAS
+       { BUILTIN_REG_ASSG      "alias", aliascmd },
+#endif
+#if JOBS
+       { BUILTIN_REGULAR       "bg", bgcmd },
+#endif
+       { BUILTIN_SPEC_REG      "break", breakcmd },
+       { BUILTIN_REGULAR       "cd", cdcmd },
+       { BUILTIN_NOSPEC        "chdir", cdcmd },
+#ifdef CONFIG_ASH_CMDCMD
+       { BUILTIN_REGULAR       "command", commandcmd },
+#endif
+       { BUILTIN_SPEC_REG      "continue", breakcmd },
+#ifdef CONFIG_ASH_BUILTIN_ECHO
+       { BUILTIN_REGULAR       "echo", echocmd },
+#endif
+       { BUILTIN_SPEC_REG      "eval", evalcmd },
+       { BUILTIN_SPEC_REG      "exec", execcmd },
+       { BUILTIN_SPEC_REG      "exit", exitcmd },
+       { BUILTIN_SPEC_REG_ASSG "export", exportcmd },
+       { BUILTIN_REGULAR       "false", falsecmd },
+#if JOBS
+       { BUILTIN_REGULAR       "fg", fgcmd },
+#endif
+#ifdef CONFIG_ASH_GETOPTS
+       { BUILTIN_REGULAR       "getopts", getoptscmd },
+#endif
+       { BUILTIN_NOSPEC        "hash", hashcmd },
+#ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
+       { BUILTIN_NOSPEC        "help", helpcmd },
+#endif
+#if JOBS
+       { BUILTIN_REGULAR       "jobs", jobscmd },
+       { BUILTIN_REGULAR       "kill", killcmd },
+#endif
+#ifdef CONFIG_ASH_MATH_SUPPORT
+       { BUILTIN_NOSPEC        "let", letcmd },
+#endif
+       { BUILTIN_ASSIGN        "local", localcmd },
+       { BUILTIN_NOSPEC        "pwd", pwdcmd },
+       { BUILTIN_REGULAR       "read", readcmd },
+       { BUILTIN_SPEC_REG_ASSG "readonly", exportcmd },
+       { BUILTIN_SPEC_REG      "return", returncmd },
+       { BUILTIN_SPEC_REG      "set", setcmd },
+       { BUILTIN_SPEC_REG      "shift", shiftcmd },
+       { BUILTIN_SPEC_REG      "source", dotcmd },
+#ifdef CONFIG_ASH_BUILTIN_TEST
+       { BUILTIN_REGULAR       "test", testcmd },
+#endif
+       { BUILTIN_SPEC_REG      "times", timescmd },
+       { BUILTIN_SPEC_REG      "trap", trapcmd },
+       { BUILTIN_REGULAR       "true", truecmd },
+       { BUILTIN_NOSPEC        "type", typecmd },
+       { BUILTIN_NOSPEC        "ulimit", ulimitcmd },
+       { BUILTIN_REGULAR       "umask", umaskcmd },
+#ifdef CONFIG_ASH_ALIAS
+       { BUILTIN_REGULAR       "unalias", unaliascmd },
+#endif
+       { BUILTIN_SPEC_REG      "unset", unsetcmd },
+       { BUILTIN_REGULAR       "wait", waitcmd },
+};
+
+#define NUMBUILTINS  (sizeof (builtincmd) / sizeof (struct builtincmd) )
+
+
+
+struct cmdentry {
+       int cmdtype;
+       union param {
+               int index;
+               const struct builtincmd *cmd;
+               struct funcnode *func;
+       } u;
+};
+
+
+/* action to find_command() */
+#define DO_ERR          0x01    /* prints errors */
+#define DO_ABS          0x02    /* checks absolute paths */
+#define DO_NOFUNC       0x04    /* don't return shell functions, for command */
+#define DO_ALTPATH      0x08    /* using alternate path */
+#define DO_ALTBLTIN     0x20    /* %builtin in alt. path */
+
+static const char *pathopt;     /* set by padvance */
+
+static void shellexec(char **, const char *, int)
+    ATTRIBUTE_NORETURN;
+static char *padvance(const char **, const char *);
+static void find_command(char *, struct cmdentry *, int, const char *);
+static struct builtincmd *find_builtin(const char *);
+static void hashcd(void);
+static void changepath(const char *);
+static void defun(char *, union node *);
+static void unsetfunc(const char *);
+
+#ifdef CONFIG_ASH_MATH_SUPPORT_64
+typedef int64_t arith_t;
+#define arith_t_type (long long)
 #else
-static void rmescapes (char *);
+typedef long arith_t;
+#define arith_t_type (long)
 #endif
 
-static int  casematch (union node *, const char *);
-static void clearredir(void);
-static void popstring(void);
-static void readcmdfile (const char *);
+#ifdef CONFIG_ASH_MATH_SUPPORT
+static arith_t dash_arith(const char *);
+static arith_t arith(const char *expr, int *perrcode);
+#endif
 
-static int number (const char *);
-static int is_number (const char *, int *num);
-static char *single_quote (const char *);
-static int nextopt (const char *);
+#ifdef CONFIG_ASH_RANDOM_SUPPORT
+static unsigned long rseed;
+static void change_random(const char *);
+# ifndef DYNAMIC_VAR
+#  define DYNAMIC_VAR
+# endif
+#endif
 
-static void redirect (union node *, int);
-static void popredir (void);
-static int dup_as_newfd (int, int);
+/*      init.h        */
 
-static void changepath(const char *newval);
-static void getoptsreset(const char *value);
+static void reset(void);
 
+/*      var.h     */
 
-static int parsenleft;                  /* copy of parsefile->nleft */
-static char *parsenextc;                /* copy of parsefile->nextc */
-static int rootpid;     /* pid of main shell */
-static int rootshell;   /* true if we aren't a child of the main shell */
+/*
+ * Shell variables.
+ */
 
-static const char spcstr[] = " ";
-static const char snlfmt[] = "%s\n";
+/* flags */
+#define VEXPORT         0x01    /* variable is exported */
+#define VREADONLY       0x02    /* variable cannot be modified */
+#define VSTRFIXED       0x04    /* variable struct is statically allocated */
+#define VTEXTFIXED      0x08    /* text is statically allocated */
+#define VSTACK          0x10    /* text is allocated on the stack */
+#define VUNSET          0x20    /* the variable is not set */
+#define VNOFUNC         0x40    /* don't call the callback function */
+#define VNOSET          0x80    /* do not set variable - just readonly test */
+#define VNOSAVE         0x100   /* when text is on the heap before setvareq */
+#ifdef DYNAMIC_VAR
+# define VDYNAMIC        0x200   /* dynamic variable */
+# else
+# define VDYNAMIC        0
+#endif
+
+struct var {
+       struct var *next;               /* next entry in hash list */
+       int flags;                      /* flags are defined above */
+       const char *text;               /* name=value */
+       void (*func)(const char *);     /* function to be called when  */
+                                       /* the variable gets set/unset */
+};
+
+struct localvar {
+       struct localvar *next;          /* next local variable in list */
+       struct var *vp;                 /* the variable that was made local */
+       int flags;                      /* saved flags */
+       const char *text;               /* saved text */
+};
 
-static int sstrnleft;
-static int herefd = -1;
 
 static struct localvar *localvars;
 
-static struct var vifs;
-static struct var vmail;
-static struct var vmpath;
-static struct var vpath;
-static struct var vps1;
-static struct var vps2;
-static struct var voptind;
+/*
+ * Shell variables.
+ */
+
+#ifdef CONFIG_ASH_GETOPTS
+static void getoptsreset(const char *);
+#endif
+
 #ifdef CONFIG_LOCALE_SUPPORT
-static struct var vlc_all;
-static struct var vlc_ctype;
+#include <locale.h>
+static void change_lc_all(const char *value);
+static void change_lc_ctype(const char *value);
 #endif
 
-struct varinit {
-       struct var *var;
-       int flags;
-       const char *text;
-       void (*func) (const char *);
-};
 
-static const char defpathvar[] =
-       "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin";
-#define defpath (defpathvar + 5)
+#define VTABSIZE 39
 
+static const char defpathvar[] = "PATH=/usr/local/bin:/usr/bin:/sbin:/bin";
 #ifdef IFS_BROKEN
 static const char defifsvar[] = "IFS= \t\n";
 #define defifs (defifsvar + 4)
@@ -1200,40 +1505,56 @@ static const char defifsvar[] = "IFS= \t\n";
 static const char defifs[] = " \t\n";
 #endif
 
-static const struct varinit varinit[] = {
+
+static struct var varinit[] = {
 #ifdef IFS_BROKEN
-       { &vifs,        VSTRFIXED|VTEXTFIXED,           defifsvar,
+       { 0,    VSTRFIXED|VTEXTFIXED,           defifsvar,      0 },
 #else
-       { &vifs,        VSTRFIXED|VTEXTFIXED|VUNSET,    "IFS=",
-#endif
-         NULL },
-       { &vmail,       VSTRFIXED|VTEXTFIXED|VUNSET,    "MAIL=",
-         NULL },
-       { &vmpath,      VSTRFIXED|VTEXTFIXED|VUNSET,    "MAILPATH=",
-         NULL },
-       { &vpath,       VSTRFIXED|VTEXTFIXED,           defpathvar,
-         changepath },
-#if defined(CONFIG_FEATURE_COMMAND_EDITING) && defined(CONFIG_FEATURE_SH_FANCY_PROMPT)
-       { &vps1,        VSTRFIXED|VTEXTFIXED,           "PS1=\\w \\$ ",
-         NULL },
-#endif /* else vps1 depends on uid */
-       { &vps2,        VSTRFIXED|VTEXTFIXED,           "PS2=> ",
-         NULL },
-       { &voptind,     VSTRFIXED|VTEXTFIXED,           "OPTIND=1",
-         getoptsreset },
+       { 0,    VSTRFIXED|VTEXTFIXED|VUNSET,    "IFS\0",        0 },
+#endif
+
+#ifdef CONFIG_ASH_MAIL
+       { 0,    VSTRFIXED|VTEXTFIXED|VUNSET,    "MAIL\0",       changemail },
+       { 0,    VSTRFIXED|VTEXTFIXED|VUNSET,    "MAILPATH\0",   changemail },
+#endif
+
+       { 0,    VSTRFIXED|VTEXTFIXED,           defpathvar,     changepath },
+       { 0,    VSTRFIXED|VTEXTFIXED,           "PS1=$ ",       0          },
+       { 0,    VSTRFIXED|VTEXTFIXED,           "PS2=> ",       0          },
+       { 0,    VSTRFIXED|VTEXTFIXED,           "PS4=+ ",       0          },
+#ifdef CONFIG_ASH_GETOPTS
+       { 0,    VSTRFIXED|VTEXTFIXED,           "OPTIND=1",     getoptsreset },
+#endif
+#ifdef CONFIG_ASH_RANDOM_SUPPORT
+       {0, VSTRFIXED|VTEXTFIXED|VUNSET|VDYNAMIC, "RANDOM\0", change_random },
+#endif
 #ifdef CONFIG_LOCALE_SUPPORT
-       { &vlc_all,     VSTRFIXED|VTEXTFIXED|VUNSET,    "LC_ALL=",
-         change_lc_all },
-       { &vlc_ctype,   VSTRFIXED|VTEXTFIXED|VUNSET,    "LC_CTYPE=",
-         change_lc_ctype },
+       {0, VSTRFIXED | VTEXTFIXED | VUNSET, "LC_ALL\0", change_lc_all },
+       {0, VSTRFIXED | VTEXTFIXED | VUNSET, "LC_CTYPE\0", change_lc_ctype },
+#endif
+#ifdef CONFIG_FEATURE_COMMAND_SAVEHISTORY
+       {0, VSTRFIXED | VTEXTFIXED | VUNSET, "HISTFILE\0", NULL },
 #endif
-       { NULL, 0,                              NULL,
-         NULL }
 };
 
-#define VTABSIZE 39
-
-static struct var *vartab[VTABSIZE];
+#define vifs varinit[0]
+#ifdef CONFIG_ASH_MAIL
+#define vmail (&vifs)[1]
+#define vmpath (&vmail)[1]
+#else
+#define vmpath vifs
+#endif
+#define vpath (&vmpath)[1]
+#define vps1 (&vpath)[1]
+#define vps2 (&vps1)[1]
+#define vps4 (&vps2)[1]
+#define voptind (&vps4)[1]
+#ifdef CONFIG_ASH_GETOPTS
+#define vrandom (&voptind)[1]
+#else
+#define vrandom (&vps4)[1]
+#endif
+#define defpath (defpathvar + 5)
 
 /*
  * The following macros access the values of the above variables.
@@ -1248,390 +1569,190 @@ static struct var *vartab[VTABSIZE];
 #define pathval()       (vpath.text + 5)
 #define ps1val()        (vps1.text + 4)
 #define ps2val()        (vps2.text + 4)
+#define ps4val()        (vps4.text + 4)
 #define optindval()     (voptind.text + 7)
 
 #define mpathset()      ((vmpath.flags & VUNSET) == 0)
 
-static void initvar (void);
-static void setvar (const char *, const char *, int);
-static void setvareq (char *, int);
-static void listsetvar (struct strlist *);
-static const char *lookupvar (const char *);
-static const char *bltinlookup (const char *);
-static char **environment (void);
-static int showvarscmd (int, char **);
-static void mklocal (char *);
-static void poplocalvars (void);
-static int unsetvar (const char *);
-static int varequal (const char *, const char *);
+static void setvar(const char *, const char *, int);
+static void setvareq(char *, int);
+static void listsetvar(struct strlist *, int);
+static char *lookupvar(const char *);
+static char *bltinlookup(const char *);
+static char **listvars(int, int, char ***);
+#define environment() listvars(VEXPORT, VUNSET, 0)
+static int showvars(const char *, int, int);
+static void poplocalvars(void);
+static int unsetvar(const char *);
+#ifdef CONFIG_ASH_GETOPTS
+static int setvarsafe(const char *, const char *, int);
+#endif
+static int varcmp(const char *, const char *);
+static struct var **hashvar(const char *);
 
 
-static char *arg0;                      /* value of $0 */
-static struct shparam shellparam;       /* current positional parameters */
-static char **argptr;                   /* argument list for builtin commands */
-static char *optionarg;                 /* set by nextopt (like getopt) */
-static char *optptr;                    /* used by nextopt */
-static char *minusc;                    /* argument to -c option */
+static inline int varequal(const char *a, const char *b) {
+       return !varcmp(a, b);
+}
 
 
-#ifdef CONFIG_ASH_ALIAS
+static int loopnest;            /* current loop nesting level */
 
-#define ALIASINUSE      1
-#define ALIASDEAD       2
+/*
+ * The parsefile structure pointed to by the global variable parsefile
+ * contains information about the current file being read.
+ */
 
-#define ATABSIZE 39
 
-struct alias {
-       struct alias *next;
-       char *name;
-       char *val;
-       int flag;
+struct redirtab {
+       struct redirtab *next;
+       int renamed[10];
+       int nullredirs;
 };
 
-static struct alias *atab[ATABSIZE];
+static struct redirtab *redirlist;
+static int nullredirs;
 
-static void setalias (char *, char *);
-static struct alias **hashalias (const char *);
-static struct alias *freealias (struct alias *);
-static struct alias **__lookupalias (const char *);
+extern char **environ;
 
-static void
-setalias(char *name, char *val)
-{
-       struct alias *ap, **app;
+/*      output.h     */
 
-       app = __lookupalias(name);
-       ap = *app;
-       INTOFF;
-       if (ap) {
-               if (!(ap->flag & ALIASINUSE)) {
-                       ckfree(ap->val);
-               }
-               ap->val = xstrdup(val);
-               ap->flag &= ~ALIASDEAD;
-       } else {
-               /* not found */
-               ap = xmalloc(sizeof (struct alias));
-               ap->name = xstrdup(name);
-               ap->val = xstrdup(val);
-               ap->flag = 0;
-               ap->next = 0;
-               *app = ap;
-       }
-       INTON;
-}
 
-static int
-unalias(char *name)
-{
-       struct alias **app;
+static void outstr(const char *, FILE *);
+static void outcslow(int, FILE *);
+static void flushall(void);
+static void flusherr(void);
+static int  out1fmt(const char *, ...)
+    __attribute__((__format__(__printf__,1,2)));
+static int fmtstr(char *, size_t, const char *, ...)
+    __attribute__((__format__(__printf__,3,4)));
 
-       app = __lookupalias(name);
+static int preverrout_fd;   /* save fd2 before print debug if xflag is set. */
 
-       if (*app) {
-               INTOFF;
-               *app = freealias(*app);
-               INTON;
-               return (0);
-       }
 
-       return (1);
+static void out1str(const char *p)
+{
+       outstr(p, stdout);
 }
 
-static void
-rmaliases(void)
+static void out2str(const char *p)
 {
-       struct alias *ap, **app;
-       int i;
-
-       INTOFF;
-       for (i = 0; i < ATABSIZE; i++) {
-               app = &atab[i];
-               for (ap = *app; ap; ap = *app) {
-                       *app = freealias(*app);
-                       if (ap == *app) {
-                               app = &ap->next;
-                       }
-               }
-       }
-       INTON;
-}
-
-static void
-printalias(const struct alias *ap) {
-       char *p;
-
-       p = single_quote(ap->val);
-       printf("alias %s=%s\n", ap->name, p);
-       stunalloc(p);
+       outstr(p, stderr);
+       flusherr();
 }
 
-
 /*
- * TODO - sort output
+ * Initialization code.
  */
-static int
-aliascmd(int argc, char **argv)
-{
-       char *n, *v;
-       int ret = 0;
-       struct alias *ap;
-
-       if (argc == 1) {
-               int i;
-
-               for (i = 0; i < ATABSIZE; i++)
-                       for (ap = atab[i]; ap; ap = ap->next) {
-                               printalias(ap);
-                       }
-               return (0);
-       }
-       while ((n = *++argv) != NULL) {
-               if ((v = strchr(n+1, '=')) == NULL) { /* n+1: funny ksh stuff */
-                       if ((ap = *__lookupalias(n)) == NULL) {
-                               out2fmt("%s: %s not found\n", "alias", n);
-                               ret = 1;
-                       } else
-                               printalias(ap);
-               }
-               else {
-                       *v++ = '\0';
-                       setalias(n, v);
-               }
-       }
-
-       return (ret);
-}
-
-static int
-unaliascmd(int argc, char **argv)
-{
-       int i;
-
-       while ((i = nextopt("a")) != '\0') {
-               if (i == 'a') {
-                       rmaliases();
-                       return (0);
-               }
-       }
-       for (i = 0; *argptr; argptr++) {
-               if (unalias(*argptr)) {
-                       out2fmt("%s: %s not found\n", "unalias", *argptr);
-                       i = 1;
-               }
-       }
 
-       return (i);
-}
+/*
+ * This routine initializes the builtin variables.
+ */
 
-static struct alias **
-hashalias(const char *p)
+static inline void
+initvar(void)
 {
-       unsigned int hashval;
+       struct var *vp;
+       struct var *end;
+       struct var **vpp;
 
-       hashval = *p << 4;
-       while (*p)
-               hashval+= *p++;
-       return &atab[hashval % ATABSIZE];
+       /*
+        * PS1 depends on uid
+        */
+#if defined(CONFIG_FEATURE_COMMAND_EDITING) && defined(CONFIG_FEATURE_SH_FANCY_PROMPT)
+       vps1.text = "PS1=\\w \\$ ";
+#else
+       if (!geteuid())
+               vps1.text = "PS1=# ";
+#endif
+       vp = varinit;
+       end = vp + sizeof(varinit) / sizeof(varinit[0]);
+       do {
+               vpp = hashvar(vp->text);
+               vp->next = *vpp;
+               *vpp = vp;
+       } while (++vp < end);
 }
 
-static struct alias *
-freealias(struct alias *ap)
+static inline void
+init(void)
 {
-       struct alias *next;
 
-       if (ap->flag & ALIASINUSE) {
-               ap->flag |= ALIASDEAD;
-               return ap;
-       }
+      /* from input.c: */
+      {
+             basepf.nextc = basepf.buf = basebuf;
+      }
 
-       next = ap->next;
-       ckfree(ap->name);
-       ckfree(ap->val);
-       ckfree(ap);
-       return next;
-}
+      /* from trap.c: */
+      {
+             signal(SIGCHLD, SIG_DFL);
+      }
 
+      /* from var.c: */
+      {
+             char **envp;
+             char ppid[32];
+             const char *p;
+             struct stat st1, st2;
 
-static struct alias **
-__lookupalias(const char *name)
-{
-       struct alias **app = hashalias(name);
+             initvar();
+             for (envp = environ ; envp && *envp ; envp++) {
+                     if (strchr(*envp, '=')) {
+                             setvareq(*envp, VEXPORT|VTEXTFIXED);
+                     }
+             }
 
-       for (; *app; app = &(*app)->next) {
-               if (equal(name, (*app)->name)) {
-                       break;
-               }
-       }
+             snprintf(ppid, sizeof(ppid), "%d", (int) getppid());
+             setvar("PPID", ppid, 0);
 
-       return app;
+             p = lookupvar("PWD");
+             if (p)
+             if (*p != '/' || stat(p, &st1) || stat(".", &st2) ||
+                 st1.st_dev != st2.st_dev || st1.st_ino != st2.st_ino)
+                     p = 0;
+             setpwd(p, 0);
+      }
 }
-#endif
 
-#ifdef CONFIG_ASH_MATH_SUPPORT
-/* The generated file arith.c has been replaced with a custom hand
- * written implementation written by Aaron Lehmann <aaronl@vitelus.com>.
- * This is now part of libbb, so that it can be used by all the shells
- * in busybox. */
-static void expari (int);
-#endif
+/* PEOF (the end of file marker) */
 
-static char *trap[NSIG];                /* trap handler commands */
-static char sigmode[NSIG - 1];  /* current value of signal */
-static char gotsig[NSIG - 1];           /* indicates specified signal received */
-static int pendingsigs;                 /* indicates some signal received */
+enum {
+       INPUT_PUSH_FILE = 1,
+       INPUT_NOFILE_OK = 2,
+};
 
 /*
- * This file was generated by the mkbuiltins program.
+ * The input line number.  Input.c just defines this variable, and saves
+ * and restores it when files are pushed and popped.  The user of this
+ * package must set its value.
  */
 
-#ifdef CONFIG_ASH_JOB_CONTROL
-static int bgcmd (int, char **);
-static int fgcmd (int, char **);
-static int killcmd (int, char **);
-#endif
-static int bltincmd (int, char **);
-static int cdcmd (int, char **);
-static int breakcmd (int, char **);
-#ifdef CONFIG_ASH_CMDCMD
-static int commandcmd (int, char **);
-#endif
-static int dotcmd (int, char **);
-static int evalcmd (int, char **);
-static int execcmd (int, char **);
-static int exitcmd (int, char **);
-static int exportcmd (int, char **);
-static int histcmd (int, char **);
-static int hashcmd (int, char **);
-static int helpcmd (int, char **);
-static int jobscmd (int, char **);
-static int localcmd (int, char **);
-static int pwdcmd (int, char **);
-static int readcmd (int, char **);
-static int returncmd (int, char **);
-static int setcmd (int, char **);
-static int setvarcmd (int, char **);
-static int shiftcmd (int, char **);
-static int trapcmd (int, char **);
-static int umaskcmd (int, char **);
-#ifdef CONFIG_ASH_ALIAS
-static int aliascmd (int, char **);
-static int unaliascmd (int, char **);
-#endif
-static int unsetcmd (int, char **);
-static int waitcmd (int, char **);
-static int ulimitcmd (int, char **);
-static int timescmd (int, char **);
-#ifdef CONFIG_ASH_MATH_SUPPORT
-static int letcmd (int, char **);
-#endif
-static int typecmd (int, char **);
-#ifdef CONFIG_ASH_GETOPTS
-static int getoptscmd (int, char **);
-#endif
-
-#ifndef CONFIG_TRUE
-static int true_main (int, char **);
-#endif
-#ifndef CONFIG_FALSE
-static int false_main (int, char **);
-#endif
-
-static void     setpwd (const char *, int);
-
-
-#define BUILTIN_NOSPEC  "0"
-#define BUILTIN_SPECIAL "1"
-#define BUILTIN_REGULAR "2"
-#define BUILTIN_ASSIGN  "4"
-#define BUILTIN_SPEC_ASSG  "5"
-#define BUILTIN_REG_ASSG   "6"
+static int pgetc(void);
+static int pgetc2(void);
+static int preadbuffer(void);
+static void pungetc(void);
+static void pushstring(char *, void *);
+static void popstring(void);
+static void setinputfd(int, int);
+static void setinputstring(char *);
+static void popfile(void);
+static void popallfiles(void);
+static void closescript(void);
 
-#define IS_BUILTIN_SPECIAL(builtincmd) ((builtincmd)->name[0] & 1)
-#define IS_BUILTIN_REGULAR(builtincmd) ((builtincmd)->name[0] & 2)
-#define IS_BUILTIN_ASSIGN(builtincmd) ((builtincmd)->name[0] & 4)
 
-struct builtincmd {
-       const char *name;
-       int (*const builtinfunc) (int, char **);
-       //unsigned flags;
-};
+/*      jobs.h    */
 
 
-/* It is CRUCIAL that this listing be kept in ascii order, otherwise
- * the binary search in find_builtin() will stop working. If you value
- * your kneecaps, you'll be sure to *make sure* that any changes made
- * to this array result in the listing remaining in ascii order. You
- * have been warned.
- */
-static const struct builtincmd builtincmds[] = {
-       { BUILTIN_SPECIAL   ".", dotcmd },    /* first, see declare DOTCMD */
-       { BUILTIN_SPECIAL   ":", true_main },
-#ifdef CONFIG_ASH_ALIAS
-       { BUILTIN_REG_ASSG  "alias", aliascmd },
-#endif
-#ifdef CONFIG_ASH_JOB_CONTROL
-       { BUILTIN_REGULAR   "bg", bgcmd },
-#endif
-       { BUILTIN_SPECIAL   "break", breakcmd },
-       { BUILTIN_SPECIAL   "builtin", bltincmd },
-       { BUILTIN_REGULAR   "cd", cdcmd },
-       { BUILTIN_NOSPEC    "chdir", cdcmd },
-#ifdef CONFIG_ASH_CMDCMD
-       { BUILTIN_REGULAR   "command", commandcmd },
-#endif
-       { BUILTIN_SPECIAL   "continue", breakcmd },
-       { BUILTIN_SPECIAL   "eval", evalcmd },
-       { BUILTIN_SPECIAL   "exec", execcmd },
-       { BUILTIN_SPECIAL   "exit", exitcmd },
-       { BUILTIN_SPEC_ASSG "export", exportcmd },
-       { BUILTIN_REGULAR   "false", false_main },
-       { BUILTIN_REGULAR   "fc", histcmd },
-#ifdef CONFIG_ASH_JOB_CONTROL
-       { BUILTIN_REGULAR   "fg", fgcmd },
-#endif
-#ifdef CONFIG_ASH_GETOPTS
-       { BUILTIN_REGULAR   "getopts", getoptscmd },
-#endif
-       { BUILTIN_NOSPEC    "hash", hashcmd },
-       { BUILTIN_NOSPEC    "help", helpcmd },
-       { BUILTIN_REGULAR   "jobs", jobscmd },
-#ifdef CONFIG_ASH_JOB_CONTROL
-       { BUILTIN_REGULAR   "kill", killcmd },
-#endif
-#ifdef CONFIG_ASH_MATH_SUPPORT
-       { BUILTIN_REGULAR    "let", letcmd },
-#endif
-       { BUILTIN_ASSIGN    "local", localcmd },
-       { BUILTIN_NOSPEC    "pwd", pwdcmd },
-       { BUILTIN_REGULAR   "read", readcmd },
-       { BUILTIN_SPEC_ASSG "readonly", exportcmd },
-       { BUILTIN_SPECIAL   "return", returncmd },
-       { BUILTIN_SPECIAL   "set", setcmd },
-       { BUILTIN_NOSPEC    "setvar", setvarcmd },
-       { BUILTIN_SPECIAL   "shift", shiftcmd },
-       { BUILTIN_SPECIAL   "times", timescmd },
-       { BUILTIN_SPECIAL   "trap", trapcmd },
-       { BUILTIN_REGULAR   "true", true_main },
-       { BUILTIN_NOSPEC    "type", typecmd },
-       { BUILTIN_NOSPEC    "ulimit", ulimitcmd },
-       { BUILTIN_REGULAR   "umask", umaskcmd },
-#ifdef CONFIG_ASH_ALIAS
-       { BUILTIN_REGULAR   "unalias", unaliascmd },
-#endif
-       { BUILTIN_SPECIAL   "unset", unsetcmd },
-       { BUILTIN_REGULAR   "wait", waitcmd },
-};
-#define NUMBUILTINS  (sizeof (builtincmds) / sizeof (struct builtincmd) )
+/* Mode argument to forkshell.  Don't change FORK_FG or FORK_BG. */
+#define FORK_FG 0
+#define FORK_BG 1
+#define FORK_NOJOB 2
 
-#define DOTCMD &builtincmds[0]
-static struct builtincmd *BLTINCMD;
-static struct builtincmd *EXECCMD;
-static struct builtincmd *EVALCMD;
+/* mode flags for showjob(s) */
+#define SHOW_PGID       0x01    /* only show pgid - for jobs -p */
+#define SHOW_PID        0x04    /* include process pid */
+#define SHOW_CHANGED    0x08    /* only jobs whose state has changed */
 
-/* states */
-#define CONFIG_ASH_JOB_CONTROLTOPPED 1            /* all procs are stopped */
-#define JOBDONE 2               /* all procs are completed */
 
 /*
  * A job structure contains information about a job.  A job is either a
@@ -1641,7082 +1762,6783 @@ static struct builtincmd *EVALCMD;
  */
 
 struct procstat {
-       pid_t pid;              /* process id */
-       int status;             /* status flags (defined above) */
-       char *cmd;              /* text of command being run */
+       pid_t   pid;            /* process id */
+       int     status;         /* last process status from wait() */
+       char    *cmd;           /* text of command being run */
 };
 
+struct job {
+       struct procstat ps0;    /* status of process */
+       struct procstat *ps;    /* status or processes when more than one */
+#if JOBS
+       int stopstatus;         /* status of a stopped job */
+#endif
+       uint32_t
+               nprocs: 16,     /* number of processes */
+               state: 8,
+#define JOBRUNNING      0       /* at least one proc running */
+#define JOBSTOPPED      1       /* all procs are stopped */
+#define JOBDONE         2       /* all procs are completed */
+#if JOBS
+               sigint: 1,      /* job was killed by SIGINT */
+               jobctl: 1,      /* job running under job control */
+#endif
+               waited: 1,      /* true if this entry has been waited for */
+               used: 1,        /* true if this entry is in used */
+               changed: 1;     /* true if status has changed */
+       struct job *prev_job;   /* previous job */
+};
 
+static pid_t backgndpid;        /* pid of last background process */
 static int job_warning;         /* user was warned about stopped jobs */
+#if JOBS
+static int jobctl;              /* true if doing job control */
+#endif
 
-#ifdef CONFIG_ASH_JOB_CONTROL
-static void setjobctl(int enable);
-#else
+static struct job *makejob(union node *, int);
+static int forkshell(struct job *, union node *, int);
+static int waitforjob(struct job *);
+static int stoppedjobs(void);
+
+#if ! JOBS
 #define setjobctl(on)   /* do nothing */
+#else
+static void setjobctl(int);
+static void showjobs(FILE *, int);
 #endif
 
+/*      main.h        */
 
-struct job {
-       struct procstat ps0;    /* status of process */
-       struct procstat *ps;    /* status or processes when more than one */
-       short nprocs;           /* number of processes */
-       short pgrp;             /* process group of this job */
-       char state;             /* true if job is finished */
-       char used;              /* true if this entry is in used */
-       char changed;           /* true if status has changed */
-#ifdef CONFIG_ASH_JOB_CONTROL
-       char jobctl;            /* job running under job control */
-#endif
-};
 
-static struct job *jobtab;      /* array of jobs */
-static int njobs;               /* size of array */
-static int backgndpid = -1;     /* pid of last background process */
-#ifdef CONFIG_ASH_JOB_CONTROL
-static int initialpgrp;         /* pgrp of shell on invocation */
-static int curjob;              /* current job */
-static int jobctl;
-#endif
-static int intreceived;
+/* pid of main shell */
+static int rootpid;
+/* shell level: 0 for the main shell, 1 for its children, and so on */
+static int shlvl;
+#define rootshell (!shlvl)
 
-static struct job *makejob (const union node *, int);
-static int forkshell (struct job *, const union node *, int);
-static int waitforjob (struct job *);
+static void readcmdfile(char *);
+static int cmdloop(int);
 
-static int docd (char *, int);
-static void getpwd (void);
+/*      memalloc.h        */
 
-static char *padvance (const char **, const char *);
 
-static char nullstr[1];         /* zero length string */
-static char *curdir = nullstr;          /* current working directory */
+struct stackmark {
+       struct stack_block *stackp;
+       char *stacknxt;
+       size_t stacknleft;
+       struct stackmark *marknext;
+};
 
-static int
-cdcmd(int argc, char **argv)
-{
-       const char *dest;
-       const char *path;
-       char *p;
-       struct stat statb;
-       int print = 0;
+/* minimum size of a block */
+#define MINSIZE SHELL_ALIGN(504)
 
-       nextopt(nullstr);
-       if ((dest = *argptr) == NULL && (dest = bltinlookup("HOME")) == NULL)
-               error("HOME not set");
-       if (*dest == '\0')
-               dest = ".";
-       if (dest[0] == '-' && dest[1] == '\0') {
-               dest = bltinlookup("OLDPWD");
-               if (!dest || !*dest) {
-                       dest = curdir;
-               }
-               print = 1;
-               if (dest)
-                       print = 1;
-               else
-                       dest = ".";
-       }
-       if (*dest == '/' || (path = bltinlookup("CDPATH")) == NULL)
-               path = nullstr;
-       while ((p = padvance(&path, dest)) != NULL) {
-               if (stat(p, &statb) >= 0 && S_ISDIR(statb.st_mode)) {
-                       if (!print) {
-                               /*
-                                * XXX - rethink
-                                */
-                               if (p[0] == '.' && p[1] == '/' && p[2] != '\0')
-                                       p += 2;
-                               print = strcmp(p, dest);
-                       }
-                       if (docd(p, print) >= 0)
-                               return 0;
+struct stack_block {
+       struct stack_block *prev;
+       char space[MINSIZE];
+};
 
-               }
-       }
-       error("can't cd to %s", dest);
-       /* NOTREACHED */
-}
+static struct stack_block stackbase;
+static struct stack_block *stackp = &stackbase;
+static struct stackmark *markp;
+static char *stacknxt = stackbase.space;
+static size_t stacknleft = MINSIZE;
+static char *sstrend = stackbase.space + MINSIZE;
+static int herefd = -1;
 
 
-/*
- * Actually do the chdir.  In an interactive shell, print the
- * directory name if "print" is nonzero.
- */
+static pointer ckmalloc(size_t);
+static pointer ckrealloc(pointer, size_t);
+static char *savestr(const char *);
+static pointer stalloc(size_t);
+static void stunalloc(pointer);
+static void setstackmark(struct stackmark *);
+static void popstackmark(struct stackmark *);
+static void growstackblock(void);
+static void *growstackstr(void);
+static char *makestrspace(size_t, char *);
+static char *stnputs(const char *, size_t, char *);
+static char *stputs(const char *, char *);
 
-static int
-docd(char *dest, int print)
-{
-       TRACE(("docd(\"%s\", %d) called\n", dest, print));
-       INTOFF;
-       if (chdir(dest) < 0) {
-               INTON;
-               return -1;
-       }
-       hashcd();
-       /*
-        * Update curdir (the name of the current directory) in response to a
-        * cd command.  We also call hashcd to let the routines in exec.c know
-        * that the current directory has changed.
-        */
-       /* If dest is NULL, we don't know the current directory */
-       if (dest == NULL || curdir == nullstr)
-               setpwd(0, 1);
-       else
-               setpwd(dest, 1);
 
-       INTON;
-       if (print && iflag)
-               puts(curdir);
-       return 0;
+static inline char *_STPUTC(int c, char *p) {
+       if (p == sstrend)
+               p = growstackstr();
+       *p++ = c;
+       return p;
 }
 
+#define stackblock() ((void *)stacknxt)
+#define stackblocksize() stacknleft
+#define STARTSTACKSTR(p) ((p) = stackblock())
+#define STPUTC(c, p) ((p) = _STPUTC((c), (p)))
+#define CHECKSTRSPACE(n, p) \
+       ({ \
+               char *q = (p); \
+               size_t l = (n); \
+               size_t m = sstrend - q; \
+               if (l > m) \
+                       (p) = makestrspace(l, q); \
+               0; \
+       })
+#define USTPUTC(c, p)   (*p++ = (c))
+#define STACKSTRNUL(p)  ((p) == sstrend? (p = growstackstr(), *p = '\0') : (*p = '\0'))
+#define STUNPUTC(p)     (--p)
+#define STTOPC(p)       p[-1]
+#define STADJUST(amount, p)     (p += (amount))
 
-static int
-pwdcmd(int argc, char **argv)
-{
-       puts(curdir);
-       return 0;
-}
-
-/* Ask system the current directory */
-static void
-getpwd(void)
-{
-       curdir = xgetcwd(0);
-       if(curdir==0)
-               curdir = nullstr;
-}
-
-static void
-setpwd(const char *val, int setold)
-{
-       char *cated = NULL;
+#define grabstackstr(p) stalloc((char *)(p) - (char *)stackblock())
+#define ungrabstackstr(s, p) stunalloc((s))
+#define stackstrend() ((void *)sstrend)
 
-       if (setold) {
-               setvar("OLDPWD", curdir, VEXPORT);
-       }
-       INTOFF;
-       if (curdir != nullstr) {
-               if(val!=NULL && *val != '/')
-                       val = cated = concat_path_file(curdir, val);
-               free(curdir);
-       }
-       if (!val)
-               getpwd();
-        else
-               curdir = simplify_path(val);
-       free(cated);
-       INTON;
-       setvar("PWD", curdir, VEXPORT);
-}
+#define ckfree(p)       free((pointer)(p))
 
-/*
- * Errors and exceptions.
- */
+/*      mystring.h   */
 
-/*
- * Code to handle exceptions in C.
- */
 
-/*
- * We enclose jmp_buf in a structure so that we can declare pointers to
- * jump locations.  The global variable handler contains the location to
- * jump to when an exception occurs, and the global variable exception
- * contains a code identifying the exeception.  To implement nested
- * exception handlers, the user should save the value of handler on entry
- * to an inner scope, set handler to point to a jmploc structure for the
- * inner scope, and restore handler on exit from the scope.
- */
+#define DOLATSTRLEN 4
 
-struct jmploc {
-       jmp_buf loc;
-};
+static char *prefix(const char *, const char *);
+static int number(const char *);
+static int is_number(const char *);
+static char *single_quote(const char *);
+static char *sstrdup(const char *);
 
-/* exceptions */
-#define EXINT 0         /* SIGINT received */
-#define EXERROR 1       /* a generic error */
-#define EXSHELLPROC 2   /* execute a shell procedure */
-#define EXEXEC 3        /* command execution failed */
+#define equal(s1, s2)   (strcmp(s1, s2) == 0)
+#define scopy(s1, s2)   ((void)strcpy(s2, s1))
 
-static struct jmploc *handler;
-static int exception;
+/*      options.h */
 
-static void exverror (int, const char *, va_list)
-    __attribute__((__noreturn__));
+struct shparam {
+       int nparam;             /* # of positional parameters (without $0) */
+       unsigned char malloc;   /* if parameter list dynamically allocated */
+       char **p;               /* parameter list */
+#ifdef CONFIG_ASH_GETOPTS
+       int optind;             /* next parameter to be processed by getopts */
+       int optoff;             /* used by getopts */
+#endif
+};
 
-/*
- * Called to raise an exception.  Since C doesn't include exceptions, we
- * just do a longjmp to the exception handler.  The type of exception is
- * stored in the global variable "exception".
- */
 
-static void exraise (int) __attribute__((__noreturn__));
+#define eflag optlist[0]
+#define fflag optlist[1]
+#define Iflag optlist[2]
+#define iflag optlist[3]
+#define mflag optlist[4]
+#define nflag optlist[5]
+#define sflag optlist[6]
+#define xflag optlist[7]
+#define vflag optlist[8]
+#define Cflag optlist[9]
+#define aflag optlist[10]
+#define bflag optlist[11]
+#define uflag optlist[12]
+#define viflag optlist[13]
 
-static void
-exraise(int e)
-{
 #ifdef DEBUG
-       if (handler == NULL)
-               abort();
+#define nolog optlist[14]
+#define debug optlist[15]
 #endif
-       flushall();
-       exception = e;
-       longjmp(handler->loc, 1);
-}
 
+#ifndef CONFIG_FEATURE_COMMAND_EDITING_VI
+#define setvimode(on) viflag = 0   /* forcibly keep the option off */
+#endif
 
-/*
- * Called from trap.c when a SIGINT is received.  (If the user specifies
- * that SIGINT is to be trapped or ignored using the trap builtin, then
- * this routine is not called.)  Suppressint is nonzero when interrupts
- * are held using the INTOFF macro.  The call to _exit is necessary because
- * there is a short period after a fork before the signal handlers are
- * set to the appropriate value for the child.  (The test for iflag is
- * just defensive programming.)
- */
+/*      options.c */
 
-static void
-onint(void) {
-       sigset_t mysigset;
 
-       if (suppressint) {
-               intpending++;
-               return;
-       }
-       intpending = 0;
-       sigemptyset(&mysigset);
-       sigprocmask(SIG_SETMASK, &mysigset, NULL);
-       if (rootshell && iflag)
-               exraise(EXINT);
-       else {
-               signal(SIGINT, SIG_DFL);
-               raise(SIGINT);
-       }
-       /* NOTREACHED */
-}
+static const char *const optletters_optnames[] = {
+       "e"   "errexit",
+       "f"   "noglob",
+       "I"   "ignoreeof",
+       "i"   "interactive",
+       "m"   "monitor",
+       "n"   "noexec",
+       "s"   "stdin",
+       "x"   "xtrace",
+       "v"   "verbose",
+       "C"   "noclobber",
+       "a"   "allexport",
+       "b"   "notify",
+       "u"   "nounset",
+       "\0"  "vi",
+#ifdef DEBUG
+       "\0"  "nolog",
+       "\0"  "debug",
+#endif
+};
 
+#define optletters(n) optletters_optnames[(n)][0]
+#define optnames(n) (&optletters_optnames[(n)][1])
 
-static char *commandname;       /* currently executing command */
+#define NOPTS (sizeof(optletters_optnames)/sizeof(optletters_optnames[0]))
 
-/*
- * Exverror is called to raise the error exception.  If the first argument
- * is not NULL then error prints an error message using printf style
- * formatting.  It then raises the error exception.
- */
-static void
-exverror(int cond, const char *msg, va_list ap)
-{
-       CLEAR_PENDING_INT;
-       INTOFF;
+static char optlist[NOPTS];
 
-#ifdef DEBUG
-       if (msg)
-               TRACE(("exverror(%d, \"%s\") pid=%d\n", cond, msg, getpid()));
-       else
-               TRACE(("exverror(%d, NULL) pid=%d\n", cond, getpid()));
-#endif
-       if (msg) {
-               if (commandname)
-                       out2fmt("%s: ", commandname);
-               vfprintf(stderr, msg, ap);
-               out2c('\n');
-       }
-       exraise(cond);
-       /* NOTREACHED */
-}
 
+static char *arg0;                     /* value of $0 */
+static struct shparam shellparam;      /* $@ current positional parameters */
+static char **argptr;                  /* argument list for builtin commands */
+static char *optionarg;                /* set by nextopt (like getopt) */
+static char *optptr;                   /* used by nextopt */
 
-static void
-error(const char *msg, ...)
-{
-       va_list ap;
-       va_start(ap, msg);
-       exverror(EXERROR, msg, ap);
-       /* NOTREACHED */
-       va_end(ap);
-}
+static char *minusc;                   /* argument to -c option */
 
 
-static void
-exerror(int cond, const char *msg, ...)
-{
-       va_list ap;
-       va_start(ap, msg);
-       exverror(cond, msg, ap);
-       /* NOTREACHED */
-       va_end(ap);
-}
+static void procargs(int, char **);
+static void optschanged(void);
+static void setparam(char **);
+static void freeparam(volatile struct shparam *);
+static int shiftcmd(int, char **);
+static int setcmd(int, char **);
+static int nextopt(const char *);
 
+/*      redir.h      */
 
+/* flags passed to redirect */
+#define REDIR_PUSH 01           /* save previous values of file descriptors */
+#define REDIR_SAVEFD2 03       /* set preverrout */
 
-/*
- * Table of error messages.
- */
+union node;
+static void redirect(union node *, int);
+static void popredir(int);
+static void clearredir(int);
+static int copyfd(int, int);
+static int redirectsafe(union node *, int);
 
-struct errname {
-       short errcode;          /* error number */
-       short  action;           /* operation which encountered the error */
-};
+/*      show.h     */
 
-/*
- * Types of operations (passed to the errmsg routine).
- */
 
-#define E_OPEN 01       /* opening a file */
-#define E_CREAT 02      /* creating a file */
-#define E_EXEC 04       /* executing a program */
+#ifdef DEBUG
+static void showtree(union node *);
+static void trace(const char *, ...);
+static void tracev(const char *, va_list);
+static void trargs(char **);
+static void trputc(int);
+static void trputs(const char *);
+static void opentrace(void);
+#endif
 
-#define ALL (E_OPEN|E_CREAT|E_EXEC)
+/*      trap.h       */
 
-static const struct errname errormsg[] = {
-       { EINTR,        ALL     },
-       { EACCES,       ALL     },
-       { EIO,          ALL     },
-       { ENOENT,       E_OPEN  },
-       { ENOENT,       E_CREAT },
-       { ENOENT,       E_EXEC  },
-       { ENOTDIR,      E_OPEN  },
-       { ENOTDIR,      E_CREAT },
-       { ENOTDIR,      E_EXEC  },
-       { EISDIR,       ALL     },
-       { EEXIST,       E_CREAT },
-#ifdef EMFILE
-       { EMFILE,       ALL     },
-#endif
-       { ENFILE,       ALL     },
-       { ENOSPC,       ALL     },
-#ifdef EDQUOT
-       { EDQUOT,       ALL     },
-#endif
-#ifdef ENOSR
-       { ENOSR,        ALL     },
-#endif
-       { ENXIO,        ALL     },
-       { EROFS,        ALL     },
-       { ETXTBSY,      ALL     },
-#ifdef EAGAIN
-       { EAGAIN,       E_EXEC  },
-#endif
-       { ENOMEM,       ALL     },
-#ifdef ENOLINK
-       { ENOLINK,      ALL     },
-#endif
-#ifdef EMULTIHOP
-       { EMULTIHOP,    ALL     },
-#endif
-#ifdef ECOMM
-       { ECOMM,        ALL     },
-#endif
-#ifdef ESTALE
-       { ESTALE,       ALL     },
-#endif
-#ifdef ETIMEDOUT
-       { ETIMEDOUT,    ALL     },
-#endif
-#ifdef ELOOP
-       { ELOOP,        ALL     },
-#endif
-       { E2BIG,        E_EXEC  },
-#ifdef ELIBACC
-       { ELIBACC,      E_EXEC  },
-#endif
-};
 
-#define ERRNAME_SIZE (sizeof(errormsg)/sizeof(struct errname))
+/* trap handler commands */
+static char *trap[NSIG];
+/* current value of signal */
+static char sigmode[NSIG - 1];
+/* indicates specified signal received */
+static char gotsig[NSIG - 1];
+
+static void clear_traps(void);
+static void setsignal(int);
+static void ignoresig(int);
+static void onsig(int);
+static int dotrap(void);
+static void setinteractive(int);
+static void exitshell(void) ATTRIBUTE_NORETURN;
 
 /*
- * Return a string describing an error.  The returned string may be a
- * pointer to a static buffer that will be overwritten on the next call.
- * Action describes the operation that got the error.
+ * This routine is called when an error or an interrupt occurs in an
+ * interactive shell and control is returned to the main command loop.
  */
 
-static const char *
-errmsg(int e, int action)
+static void
+reset(void)
 {
-       struct errname const *ep;
-       static char buf[12];
+      /* from eval.c: */
+      {
+             evalskip = 0;
+             loopnest = 0;
+      }
 
-       for (ep = errormsg ; ep < errormsg+ERRNAME_SIZE; ep++) {
-               if (ep->errcode == e && (ep->action & action) != 0)
-                       return strerror(e);
-       }
+      /* from input.c: */
+      {
+             parselleft = parsenleft = 0;      /* clear input buffer */
+             popallfiles();
+      }
 
-       snprintf(buf, sizeof buf, "error %d", e);
-       return buf;
-}
+      /* from parser.c: */
+      {
+             tokpushback = 0;
+             checkkwd = 0;
+      }
 
+      /* from redir.c: */
+      {
+             clearredir(0);
+      }
 
-#ifdef CONFIG_ASH_OPTIMIZE_FOR_SIZE
-static void
-__inton() {
-       if (--suppressint == 0 && intpending) {
-               onint();
-       }
-}
-static void forceinton (void) {
-       suppressint = 0;
-       if (intpending)
-               onint();
 }
-#endif
-
-/* flags in argument to evaltree */
-#define EV_EXIT 01              /* exit after evaluating tree */
-#define EV_TESTED 02            /* exit status is checked; ignore -e flag */
-#define EV_BACKCMD 04           /* command executing within back quotes */
-
-static int evalskip;                    /* set if we are skipping commands */
-static int skipcount;           /* number of levels to skip */
-static int loopnest;            /* current loop nesting level */
-static int funcnest;                    /* depth of function calls */
 
+#ifdef CONFIG_ASH_ALIAS
+static struct alias *atab[ATABSIZE];
 
-static struct strlist *cmdenviron;      /* environment for builtin command */
-static int exitstatus;                  /* exit status of last command */
-static int oexitstatus;         /* saved exit status */
-
-static void evalsubshell (const union node *, int);
-static void expredir (union node *);
-static void eprintlist (struct strlist *);
-
-static union node *parsecmd(int);
-/*
- * Called to reset things after an exception.
- */
-
-/*
- * The eval commmand.
- */
-static void evalstring (char *, int);
+static void setalias(const char *, const char *);
+static struct alias *freealias(struct alias *);
+static struct alias **__lookupalias(const char *);
 
-static int
-evalcmd(int argc, char **argv)
+static void
+setalias(const char *name, const char *val)
 {
-       char *p;
-       char *concat;
-       char **ap;
+       struct alias *ap, **app;
 
-       if (argc > 1) {
-               p = argv[1];
-               if (argc > 2) {
-                       STARTSTACKSTR(concat);
-                       ap = argv + 2;
-                       for (;;) {
-                               while (*p)
-                                       STPUTC(*p++, concat);
-                               if ((p = *ap++) == NULL)
-                                       break;
-                               STPUTC(' ', concat);
-                       }
-                       STPUTC('\0', concat);
-                       p = grabstackstr(concat);
+       app = __lookupalias(name);
+       ap = *app;
+       INTOFF;
+       if (ap) {
+               if (!(ap->flag & ALIASINUSE)) {
+                       ckfree(ap->val);
                }
-               evalstring(p, EV_TESTED);
+               ap->val = savestr(val);
+               ap->flag &= ~ALIASDEAD;
+       } else {
+               /* not found */
+               ap = ckmalloc(sizeof (struct alias));
+               ap->name = savestr(name);
+               ap->val = savestr(val);
+               ap->flag = 0;
+               ap->next = 0;
+               *app = ap;
        }
-       return exitstatus;
+       INTON;
 }
 
-/*
- * Execute a command or commands contained in a string.
- */
+static int
+unalias(const char *name)
+{
+       struct alias **app;
+
+       app = __lookupalias(name);
 
-static void evaltree (union node *, int);
-static void setinputstring (char *);
-static void popfile (void);
-static void setstackmark(struct stackmark *mark);
-static void popstackmark(struct stackmark *mark);
+       if (*app) {
+               INTOFF;
+               *app = freealias(*app);
+               INTON;
+               return (0);
+       }
 
+       return (1);
+}
 
 static void
-evalstring(char *s, int flag)
+rmaliases(void)
 {
-       union node *n;
-       struct stackmark smark;
+       struct alias *ap, **app;
+       int i;
 
-       setstackmark(&smark);
-       setinputstring(s);
-       while ((n = parsecmd(0)) != NEOF) {
-               evaltree(n, flag);
-               popstackmark(&smark);
+       INTOFF;
+       for (i = 0; i < ATABSIZE; i++) {
+               app = &atab[i];
+               for (ap = *app; ap; ap = *app) {
+                       *app = freealias(*app);
+                       if (ap == *app) {
+                               app = &ap->next;
+                       }
+               }
        }
-       popfile();
-       popstackmark(&smark);
+       INTON;
 }
 
-static struct builtincmd *find_builtin (const char *);
-static void expandarg (union node *, struct arglist *, int);
-static void calcsize (const union node *);
-static union node *copynode (const union node *);
+static struct alias *
+lookupalias(const char *name, int check)
+{
+       struct alias *ap = *__lookupalias(name);
+
+       if (check && ap && (ap->flag & ALIASINUSE))
+               return (NULL);
+       return (ap);
+}
 
 /*
- * Make a copy of a parse tree.
+ * TODO - sort output
  */
+static int
+aliascmd(int argc, char **argv)
+{
+       char *n, *v;
+       int ret = 0;
+       struct alias *ap;
 
-static int     funcblocksize;           /* size of structures in function */
-static int     funcstringsize;          /* size of strings in node */
-static pointer funcblock;              /* block to allocate function from */
-static char   *funcstring;              /* block to allocate strings from */
+       if (argc == 1) {
+               int i;
+
+               for (i = 0; i < ATABSIZE; i++)
+                       for (ap = atab[i]; ap; ap = ap->next) {
+                               printalias(ap);
+                       }
+               return (0);
+       }
+       while ((n = *++argv) != NULL) {
+               if ((v = strchr(n+1, '=')) == NULL) { /* n+1: funny ksh stuff */
+                       if ((ap = *__lookupalias(n)) == NULL) {
+                               fprintf(stderr, "%s: %s not found\n", "alias", n);
+                               ret = 1;
+                       } else
+                               printalias(ap);
+               } else {
+                       *v++ = '\0';
+                       setalias(n, v);
+               }
+       }
 
+       return (ret);
+}
 
-static inline union node *
-copyfunc(union node *n)
+static int
+unaliascmd(int argc, char **argv)
 {
-       if (n == NULL)
-               return NULL;
-       funcblocksize = 0;
-       funcstringsize = 0;
-       calcsize(n);
-       funcblock = xmalloc(funcblocksize + funcstringsize);
-       funcstring = (char *) funcblock + funcblocksize;
-       return copynode(n);
+       int i;
+
+       while ((i = nextopt("a")) != '\0') {
+               if (i == 'a') {
+                       rmaliases();
+                       return (0);
+               }
+       }
+       for (i = 0; *argptr; argptr++) {
+               if (unalias(*argptr)) {
+                       fprintf(stderr, "%s: %s not found\n", "unalias", *argptr);
+                       i = 1;
+               }
+       }
+
+       return (i);
 }
 
-/*
- * Free a parse tree.
- */
+static struct alias *
+freealias(struct alias *ap) {
+       struct alias *next;
+
+       if (ap->flag & ALIASINUSE) {
+               ap->flag |= ALIASDEAD;
+               return ap;
+       }
+
+       next = ap->next;
+       ckfree(ap->name);
+       ckfree(ap->val);
+       ckfree(ap);
+       return next;
+}
 
 static void
-freefunc(union node *n)
-{
-       if (n)
-               ckfree(n);
+printalias(const struct alias *ap) {
+       out1fmt("%s=%s\n", ap->name, single_quote(ap->val));
 }
 
+static struct alias **
+__lookupalias(const char *name) {
+       unsigned int hashval;
+       struct alias **app;
+       const char *p;
+       unsigned int ch;
 
-/*
- * Add a new command entry, replacing any existing command entry for
- * the same name.
- */
+       p = name;
 
-static inline void
-addcmdentry(char *name, struct cmdentry *entry)
-{
-       struct tblentry *cmdp;
+       ch = (unsigned char)*p;
+       hashval = ch << 4;
+       while (ch) {
+               hashval += ch;
+               ch = (unsigned char)*++p;
+       }
+       app = &atab[hashval % ATABSIZE];
 
-       INTOFF;
-       cmdp = cmdlookup(name, 1);
-       if (cmdp->cmdtype == CMDFUNCTION) {
-               freefunc(cmdp->param.func);
+       for (; *app; app = &(*app)->next) {
+               if (equal(name, (*app)->name)) {
+                       break;
+               }
        }
-       cmdp->cmdtype = entry->cmdtype;
-       cmdp->param = entry->u;
-       INTON;
+
+       return app;
 }
+#endif /* CONFIG_ASH_ALIAS */
 
-static inline void
-evalloop(const union node *n, int flags)
+
+/*      cd.c      */
+
+/*
+ * The cd and pwd commands.
+ */
+
+#define CD_PHYSICAL 1
+#define CD_PRINT 2
+
+static int docd(const char *, int);
+static int cdopt(void);
+
+static char *curdir = nullstr;          /* current working directory */
+static char *physdir = nullstr;         /* physical working directory */
+
+static int
+cdopt(void)
 {
-       int status;
+       int flags = 0;
+       int i, j;
 
-       loopnest++;
-       status = 0;
-       for (;;) {
-               evaltree(n->nbinary.ch1, EV_TESTED);
-               if (evalskip) {
-skipping:         if (evalskip == SKIPCONT && --skipcount <= 0) {
-                               evalskip = 0;
-                               continue;
-                       }
-                       if (evalskip == SKIPBREAK && --skipcount <= 0)
-                               evalskip = 0;
-                       break;
-               }
-               if (n->type == NWHILE) {
-                       if (exitstatus != 0)
-                               break;
-               } else {
-                       if (exitstatus == 0)
-                               break;
+       j = 'L';
+       while ((i = nextopt("LP"))) {
+               if (i != j) {
+                       flags ^= CD_PHYSICAL;
+                       j = i;
                }
-               evaltree(n->nbinary.ch2, flags & EV_TESTED);
-               status = exitstatus;
-               if (evalskip)
-                       goto skipping;
        }
-       loopnest--;
-       exitstatus = status;
+
+       return flags;
 }
 
-static void
-evalfor(const union node *n, int flags)
+static int
+cdcmd(int argc, char **argv)
 {
-       struct arglist arglist;
-       union node *argp;
-       struct strlist *sp;
-       struct stackmark smark;
+       const char *dest;
+       const char *path;
+       const char *p;
+       char c;
+       struct stat statb;
+       int flags;
 
-       setstackmark(&smark);
-       arglist.lastp = &arglist.list;
-       for (argp = n->nfor.args ; argp ; argp = argp->narg.next) {
-               oexitstatus = exitstatus;
-               expandarg(argp, &arglist, EXP_FULL | EXP_TILDE | EXP_RECORD);
-               if (evalskip)
-                       goto out;
+       flags = cdopt();
+       dest = *argptr;
+       if (!dest)
+               dest = bltinlookup(homestr);
+       else if (dest[0] == '-' && dest[1] == '\0') {
+               dest = bltinlookup("OLDPWD");
+               flags |= CD_PRINT;
+       }
+       if (!dest)
+               dest = nullstr;
+       if (*dest == '/')
+               goto step7;
+       if (*dest == '.') {
+               c = dest[1];
+dotdot:
+               switch (c) {
+               case '\0':
+               case '/':
+                       goto step6;
+               case '.':
+                       c = dest[2];
+                       if (c != '.')
+                               goto dotdot;
+               }
        }
-       *arglist.lastp = NULL;
-
-       exitstatus = 0;
-       loopnest++;
-       for (sp = arglist.list ; sp ; sp = sp->next) {
-               setvar(n->nfor.var, sp->text, 0);
-               evaltree(n->nfor.body, flags & EV_TESTED);
-               if (evalskip) {
-                       if (evalskip == SKIPCONT && --skipcount <= 0) {
-                               evalskip = 0;
-                               continue;
-                       }
-                       if (evalskip == SKIPBREAK && --skipcount <= 0)
-                               evalskip = 0;
+       if (!*dest)
+               dest = ".";
+       if (!(path = bltinlookup("CDPATH"))) {
+step6:
+step7:
+               p = dest;
+               goto docd;
+       }
+       do {
+               c = *path;
+               p = padvance(&path, dest);
+               if (stat(p, &statb) >= 0 && S_ISDIR(statb.st_mode)) {
+                       if (c && c != ':')
+                               flags |= CD_PRINT;
+docd:
+                       if (!docd(p, flags))
+                               goto out;
                        break;
                }
-       }
-       loopnest--;
+       } while (path);
+       sh_error("can't cd to %s", dest);
+       /* NOTREACHED */
 out:
-       popstackmark(&smark);
+       if (flags & CD_PRINT)
+               out1fmt(snlfmt, curdir);
+       return 0;
 }
 
-static inline void
-evalcase(const union node *n, int flags)
+
+/*
+ * Update curdir (the name of the current directory) in response to a
+ * cd command.
+ */
+
+static inline const char *
+updatepwd(const char *dir)
 {
-       union node *cp;
-       union node *patp;
-       struct arglist arglist;
-       struct stackmark smark;
+       char *new;
+       char *p;
+       char *cdcomppath;
+       const char *lim;
 
-       setstackmark(&smark);
-       arglist.lastp = &arglist.list;
-       oexitstatus = exitstatus;
-       expandarg(n->ncase.expr, &arglist, EXP_TILDE);
-       for (cp = n->ncase.cases ; cp && evalskip == 0 ; cp = cp->nclist.next) {
-               for (patp = cp->nclist.pattern ; patp ; patp = patp->narg.next) {
-                       if (casematch(patp, arglist.list->text)) {
-                               if (evalskip == 0) {
-                                       evaltree(cp->nclist.body, flags);
+       cdcomppath = sstrdup(dir);
+       STARTSTACKSTR(new);
+       if (*dir != '/') {
+               if (curdir == nullstr)
+                       return 0;
+               new = stputs(curdir, new);
+       }
+       new = makestrspace(strlen(dir) + 2, new);
+       lim = stackblock() + 1;
+       if (*dir != '/') {
+               if (new[-1] != '/')
+                       USTPUTC('/', new);
+               if (new > lim && *lim == '/')
+                       lim++;
+       } else {
+               USTPUTC('/', new);
+               cdcomppath++;
+               if (dir[1] == '/' && dir[2] != '/') {
+                       USTPUTC('/', new);
+                       cdcomppath++;
+                       lim++;
+               }
+       }
+       p = strtok(cdcomppath, "/");
+       while (p) {
+               switch(*p) {
+               case '.':
+                       if (p[1] == '.' && p[2] == '\0') {
+                               while (new > lim) {
+                                       STUNPUTC(new);
+                                       if (new[-1] == '/')
+                                               break;
                                }
-                               goto out;
-                       }
+                               break;
+                       } else if (p[1] == '\0')
+                               break;
+                       /* fall through */
+               default:
+                       new = stputs(p, new);
+                       USTPUTC('/', new);
                }
+               p = strtok(0, "/");
        }
-out:
-       popstackmark(&smark);
+       if (new > lim)
+               STUNPUTC(new);
+       *new = 0;
+       return stackblock();
 }
 
 /*
- * Evaluate a pipeline.  All the processes in the pipeline are children
- * of the process creating the pipeline.  (This differs from some versions
- * of the shell, which make the last process in a pipeline the parent
- * of all the rest.)
+ * Actually do the chdir.  We also call hashcd to let the routines in exec.c
+ * know that the current directory has changed.
  */
 
-static inline void evalpipe(union node *n)
+static int
+docd(const char *dest, int flags)
 {
-       struct job *jp;
-       struct nodelist *lp;
-       int pipelen;
-       int prevfd;
-       int pip[2];
+       const char *dir = 0;
+       int err;
 
-       TRACE(("evalpipe(0x%lx) called\n", (long)n));
-       pipelen = 0;
-       for (lp = n->npipe.cmdlist ; lp ; lp = lp->next)
-               pipelen++;
-       INTOFF;
-       jp = makejob(n, pipelen);
-       prevfd = -1;
-       for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
-               /*
-                * Search for a command.  This is called before we fork so that the
-                * location of the command will be available in the parent as well as
-                * the child.  The check for "goodname" is an overly conservative
-                * check that the name will not be subject to expansion.
-                */
+       TRACE(("docd(\"%s\", %d) called\n", dest, flags));
 
-               struct cmdentry entry;
-               union node *lpn = lp->n;
-               if (lpn->type == NCMD && lpn->ncmd.args && goodname(lpn->ncmd.args->narg.text))
-                       find_command(lpn->ncmd.args->narg.text, &entry, 0, pathval());
+       INTOFF;
+       if (!(flags & CD_PHYSICAL)) {
+               dir = updatepwd(dest);
+               if (dir)
+                       dest = dir;
+       }
+       err = chdir(dest);
+       if (err)
+               goto out;
+       setpwd(dir, 1);
+       hashcd();
+out:
+       INTON;
+       return err;
+}
 
-               pip[1] = -1;
-               if (lp->next) {
-                       if (pipe(pip) < 0) {
-                               close(prevfd);
-                               error("Pipe call failed");
-                       }
-               }
-               if (forkshell(jp, lp->n, n->npipe.backgnd) == 0) {
-                       INTON;
-                       if (prevfd > 0) {
-                               close(0);
-                               dup_as_newfd(prevfd, 0);
-                               close(prevfd);
-                               if (pip[0] == 0) {
-                                       pip[0] = -1;
-                               }
-                       }
-                       if (pip[1] >= 0) {
-                               if (pip[0] >= 0) {
-                                       close(pip[0]);
-                               }
-                               if (pip[1] != 1) {
-                                       close(1);
-                                       dup_as_newfd(pip[1], 1);
-                                       close(pip[1]);
-                               }
-                       }
-                       evaltree(lp->n, EV_EXIT);
-               }
-               if (prevfd >= 0)
-                       close(prevfd);
-               prevfd = pip[0];
-               close(pip[1]);
-       }
-       INTON;
-       if (n->npipe.backgnd == 0) {
-               INTOFF;
-               exitstatus = waitforjob(jp);
-               TRACE(("evalpipe:  job done exit status %d\n", exitstatus));
-               INTON;
-       }
+/*
+ * Find out what the current directory is. If we already know the current
+ * directory, this routine returns immediately.
+ */
+static inline char *
+getpwd(void)
+{
+       char *dir = getcwd(0, 0);
+       return dir ? dir : nullstr;
 }
 
 static int
-isassignment(const char *word) {
-       if (!is_name(*word)) {
-               return 0;
+pwdcmd(int argc, char **argv)
+{
+       int flags;
+       const char *dir = curdir;
+
+       flags = cdopt();
+       if (flags) {
+               if (physdir == nullstr)
+                       setpwd(dir, 0);
+               dir = physdir;
        }
-       do {
-               word++;
-       } while (is_in_name(*word));
-       return *word == '=';
+       out1fmt(snlfmt, dir);
+       return 0;
 }
 
-
 static void
-evalcommand(union node *cmd, int flags)
+setpwd(const char *val, int setold)
 {
-       struct stackmark smark;
-       union node *argp;
-       struct arglist arglist;
-       struct arglist varlist;
-       char **argv;
-       int argc;
-       char **envp;
-       struct strlist *sp;
-       int mode;
-       struct cmdentry cmdentry;
-       struct job *jp;
-       char *volatile savecmdname;
-       volatile struct shparam saveparam;
-       struct localvar *volatile savelocalvars;
-       volatile int e;
-       char *lastarg;
-       const char *path;
-       const struct builtincmd *firstbltin;
-       struct jmploc *volatile savehandler;
-       struct jmploc jmploc;
-#if __GNUC__
-       /* Avoid longjmp clobbering */
-       (void) &argv;
-       (void) &argc;
-       (void) &lastarg;
-       (void) &flags;
-#endif
+       char *oldcur, *dir;
 
-       /* First expand the arguments. */
-       TRACE(("evalcommand(0x%lx, %d) called\n", (long)cmd, flags));
-       setstackmark(&smark);
-       arglist.lastp = &arglist.list;
-       varlist.lastp = &varlist.list;
-       arglist.list = 0;
-       oexitstatus = exitstatus;
-       exitstatus = 0;
-       path = pathval();
-       for (argp = cmd->ncmd.assign; argp; argp = argp->narg.next) {
-               expandarg(argp, &varlist, EXP_VARTILDE);
-       }
-       for (
-               argp = cmd->ncmd.args; argp && !arglist.list;
-               argp = argp->narg.next
-       ) {
-               expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
-       }
-       if (argp) {
-               struct builtincmd *bcmd;
-               int pseudovarflag;
-               bcmd = find_builtin(arglist.list->text);
-               pseudovarflag = bcmd && IS_BUILTIN_ASSIGN(bcmd);
-               for (; argp; argp = argp->narg.next) {
-                       if (pseudovarflag && isassignment(argp->narg.text)) {
-                               expandarg(argp, &arglist, EXP_VARTILDE);
-                               continue;
-                       }
-                       expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
-               }
-       }
-       *arglist.lastp = NULL;
-       *varlist.lastp = NULL;
-       expredir(cmd->ncmd.redirect);
-       argc = 0;
-       for (sp = arglist.list ; sp ; sp = sp->next)
-               argc++;
-       argv = stalloc(sizeof (char *) * (argc + 1));
+       oldcur = dir = curdir;
 
-       for (sp = arglist.list ; sp ; sp = sp->next) {
-               TRACE(("evalcommand arg: %s\n", sp->text));
-               *argv++ = sp->text;
+       if (setold) {
+               setvar("OLDPWD", oldcur, VEXPORT);
        }
-       *argv = NULL;
-       lastarg = NULL;
-       if (iflag && funcnest == 0 && argc > 0)
-               lastarg = argv[-1];
-       argv -= argc;
-
-       /* Print the command if xflag is set. */
-       if (xflag) {
-               out2c('+');
-               eprintlist(varlist.list);
-               eprintlist(arglist.list);
-               out2c('\n');
+       INTOFF;
+       if (physdir != nullstr) {
+               if (physdir != oldcur)
+                       free(physdir);
+               physdir = nullstr;
+       }
+       if (oldcur == val || !val) {
+               char *s = getpwd();
+               physdir = s;
+               if (!val)
+                       dir = s;
+       } else
+               dir = savestr(val);
+       if (oldcur != dir && oldcur != nullstr) {
+               free(oldcur);
        }
+       curdir = dir;
+       INTON;
+       setvar("PWD", dir, VEXPORT);
+}
 
-       /* Now locate the command. */
-       if (argc == 0) {
-               cmdentry.cmdtype = CMDBUILTIN;
-               firstbltin = cmdentry.u.cmd = BLTINCMD;
-       } else {
-               const char *oldpath;
-               int findflag = DO_ERR;
-               int oldfindflag;
+/*      error.c   */
 
-               /*
-                * Modify the command lookup path, if a PATH= assignment
-                * is present
-                */
-               for (sp = varlist.list ; sp ; sp = sp->next)
-                       if (varequal(sp->text, defpathvar)) {
-                               path = sp->text + 5;
-                               findflag |= DO_BRUTE;
-                       }
-               oldpath = path;
-               oldfindflag = findflag;
-               firstbltin = 0;
-               for(;;) {
-                       find_command(argv[0], &cmdentry, findflag, path);
-                       if (cmdentry.cmdtype == CMDUNKNOWN) {   /* command not found */
-                               exitstatus = 127;
-                               goto out;
-                       }
-                       /* implement bltin and command here */
-                       if (cmdentry.cmdtype != CMDBUILTIN) {
-                               break;
-                       }
-                       if (!firstbltin) {
-                               firstbltin = cmdentry.u.cmd;
-                       }
-                       if (cmdentry.u.cmd == BLTINCMD) {
-                               for(;;) {
-                                       struct builtincmd *bcmd;
-
-                                       argv++;
-                                       if (--argc == 0)
-                                               goto found;
-                                       if (!(bcmd = find_builtin(*argv))) {
-                                               out2fmt("%s: not found\n", *argv);
-                                               exitstatus = 127;
-                                               goto out;
-                                       }
-                                       cmdentry.u.cmd = bcmd;
-                                       if (bcmd != BLTINCMD)
-                                               break;
-                               }
-                       }
-                       if (cmdentry.u.cmd == find_builtin("command")) {
-                               argv++;
-                               if (--argc == 0) {
-                                       goto found;
-                               }
-                               if (*argv[0] == '-') {
-                                       if (!equal(argv[0], "-p")) {
-                                               argv--;
-                                               argc++;
-                                               break;
-                                       }
-                                       argv++;
-                                       if (--argc == 0) {
-                                               goto found;
-                                       }
-                                       path = defpath;
-                                       findflag |= DO_BRUTE;
-                               } else {
-                                       path = oldpath;
-                                       findflag = oldfindflag;
-                               }
-                               findflag |= DO_NOFUN;
-                               continue;
-                       }
-found:
-                       break;
-               }
-       }
+/*
+ * Errors and exceptions.
+ */
 
-       /* Fork off a child process if necessary. */
-       if (cmd->ncmd.backgnd
-        || (cmdentry.cmdtype == CMDNORMAL && (flags & EV_EXIT) == 0)
-       ) {
-               jp = makejob(cmd, 1);
-               mode = cmd->ncmd.backgnd;
-               if (forkshell(jp, cmd, mode) != 0)
-                       goto parent;    /* at end of routine */
-               flags |= EV_EXIT;
-       }
+/*
+ * Code to handle exceptions in C.
+ */
 
-       /* This is the child process if a fork occurred. */
-       /* Execute the command. */
-       if (cmdentry.cmdtype == CMDFUNCTION) {
-#ifdef DEBUG
-               trputs("Shell function:  ");  trargs(argv);
-#endif
-               exitstatus = oexitstatus;
-               redirect(cmd->ncmd.redirect, REDIR_PUSH);
-               saveparam = shellparam;
-               shellparam.malloc = 0;
-               shellparam.nparam = argc - 1;
-               shellparam.p = argv + 1;
-               INTOFF;
-               savelocalvars = localvars;
-               localvars = NULL;
-               INTON;
-               if (setjmp(jmploc.loc)) {
-                       if (exception == EXSHELLPROC) {
-                               freeparam((volatile struct shparam *)
-                                   &saveparam);
-                       } else {
-                               saveparam.optind = shellparam.optind;
-                               saveparam.optoff = shellparam.optoff;
-                               freeparam(&shellparam);
-                               shellparam = saveparam;
-                       }
-                       poplocalvars();
-                       localvars = savelocalvars;
-                       handler = savehandler;
-                       longjmp(handler->loc, 1);
-               }
-               savehandler = handler;
-               handler = &jmploc;
-               for (sp = varlist.list ; sp ; sp = sp->next)
-                       mklocal(sp->text);
-               funcnest++;
-               evaltree(cmdentry.u.func, flags & EV_TESTED);
-               funcnest--;
-               INTOFF;
-               poplocalvars();
-               localvars = savelocalvars;
-               saveparam.optind = shellparam.optind;
-               saveparam.optoff = shellparam.optoff;
-               freeparam(&shellparam);
-               shellparam = saveparam;
-               handler = savehandler;
-               popredir();
-               INTON;
-               if (evalskip == SKIPFUNC) {
-                       evalskip = 0;
-                       skipcount = 0;
-               }
-               if (flags & EV_EXIT)
-                       exitshell(exitstatus);
-       } else if (cmdentry.cmdtype == CMDBUILTIN) {
-#ifdef DEBUG
-               trputs("builtin command:  ");  trargs(argv);
-#endif
-               mode = (cmdentry.u.cmd == EXECCMD)? 0 : REDIR_PUSH;
-               redirect(cmd->ncmd.redirect, mode);
-               savecmdname = commandname;
-               if (IS_BUILTIN_SPECIAL(firstbltin)) {
-                       listsetvar(varlist.list);
-               } else {
-                       cmdenviron = varlist.list;
-               }
-               e = -1;
-               if (setjmp(jmploc.loc)) {
-                       e = exception;
-                       exitstatus = (e == EXINT)? SIGINT+128 : 2;
-                       goto cmddone;
-               }
-               savehandler = handler;
-               handler = &jmploc;
-               commandname = argv[0];
-               argptr = argv + 1;
-               optptr = NULL;                  /* initialize nextopt */
-               exitstatus = (*cmdentry.u.cmd->builtinfunc)(argc, argv);
-               flushall();
-cmddone:
-               cmdenviron = NULL;
-               if (e != EXSHELLPROC) {
-                       commandname = savecmdname;
-                       if (flags & EV_EXIT)
-                               exitshell(exitstatus);
-               }
-               handler = savehandler;
-               if (e != -1) {
-                       if ((e != EXERROR && e != EXEXEC)
-                          || cmdentry.u.cmd == BLTINCMD
-                          || cmdentry.u.cmd == DOTCMD
-                          || cmdentry.u.cmd == EVALCMD
-                          || cmdentry.u.cmd == EXECCMD)
-                               exraise(e);
-                       FORCEINTON;
-               }
-               if (cmdentry.u.cmd != EXECCMD)
-                       popredir();
-       } else {
-#ifdef DEBUG
-               trputs("normal command:  ");  trargs(argv);
-#endif
-               redirect(cmd->ncmd.redirect, 0);
-               clearredir();
-               for (sp = varlist.list ; sp ; sp = sp->next)
-                       setvareq(sp->text, VEXPORT|VSTACK);
-               envp = environment();
-               shellexec(argv, envp, path, cmdentry.u.index);
-       }
-       goto out;
 
-parent: /* parent process gets here (if we forked) */
-       if (mode == 0) {        /* argument to fork */
-               INTOFF;
-               exitstatus = waitforjob(jp);
-               INTON;
-       }
 
-out:
-       if (lastarg)
-               setvar("_", lastarg, 0);
-       popstackmark(&smark);
-}
+static void exverror(int, const char *, va_list)
+    ATTRIBUTE_NORETURN;
 
 /*
- * Evaluate a parse tree.  The value is left in the global variable
- * exitstatus.
+ * Called to raise an exception.  Since C doesn't include exceptions, we
+ * just do a longjmp to the exception handler.  The type of exception is
+ * stored in the global variable "exception".
  */
+
 static void
-evaltree(union node *n, int flags)
+exraise(int e)
 {
-       int checkexit = 0;
-       if (n == NULL) {
-               TRACE(("evaltree(NULL) called\n"));
-               goto out;
-       }
-       TRACE(("evaltree(0x%lx: %d) called\n", (long)n, n->type));
-       switch (n->type) {
-       case NSEMI:
-               evaltree(n->nbinary.ch1, flags & EV_TESTED);
-               if (evalskip)
-                       goto out;
-               evaltree(n->nbinary.ch2, flags);
-               break;
-       case NAND:
-               evaltree(n->nbinary.ch1, EV_TESTED);
-               if (evalskip || exitstatus != 0)
-                       goto out;
-               evaltree(n->nbinary.ch2, flags);
-               break;
-       case NOR:
-               evaltree(n->nbinary.ch1, EV_TESTED);
-               if (evalskip || exitstatus == 0)
-                       goto out;
-               evaltree(n->nbinary.ch2, flags);
-               break;
-       case NREDIR:
-               expredir(n->nredir.redirect);
-               redirect(n->nredir.redirect, REDIR_PUSH);
-               evaltree(n->nredir.n, flags);
-               popredir();
-               break;
-       case NSUBSHELL:
-               evalsubshell(n, flags);
-               break;
-       case NBACKGND:
-               evalsubshell(n, flags);
-               break;
-       case NIF: {
-               evaltree(n->nif.test, EV_TESTED);
-               if (evalskip)
-                       goto out;
-               if (exitstatus == 0)
-                       evaltree(n->nif.ifpart, flags);
-               else if (n->nif.elsepart)
-                       evaltree(n->nif.elsepart, flags);
-               else
-                       exitstatus = 0;
-               break;
-       }
-       case NWHILE:
-       case NUNTIL:
-               evalloop(n, flags);
-               break;
-       case NFOR:
-               evalfor(n, flags);
-               break;
-       case NCASE:
-               evalcase(n, flags);
-               break;
-       case NDEFUN: {
-               struct builtincmd *bcmd;
-               struct cmdentry entry;
-               if (
-                       (bcmd = find_builtin(n->narg.text)) &&
-                       IS_BUILTIN_SPECIAL(bcmd)
-               ) {
-                       out2fmt("%s is a special built-in\n", n->narg.text);
-                       exitstatus = 1;
-                       break;
-               }
-               entry.cmdtype = CMDFUNCTION;
-               entry.u.func = copyfunc(n->narg.next);
-               addcmdentry(n->narg.text, &entry);
-               exitstatus = 0;
-               break;
-       }
-       case NNOT:
-               evaltree(n->nnot.com, EV_TESTED);
-               exitstatus = !exitstatus;
-               break;
-
-       case NPIPE:
-               evalpipe(n);
-               checkexit = 1;
-               break;
-       case NCMD:
-               evalcommand(n, flags);
-               checkexit = 1;
-               break;
 #ifdef DEBUG
-       default:
-               printf("Node type = %d\n", n->type);
-               break;
+       if (handler == NULL)
+               abort();
 #endif
-       }
-out:
-       if (pendingsigs)
-               dotrap();
-       if (
-               flags & EV_EXIT ||
-               (checkexit && eflag && exitstatus && !(flags & EV_TESTED))
-       )
-               exitshell(exitstatus);
+       INTOFF;
+
+       exception = e;
+       longjmp(handler->loc, 1);
 }
 
+
 /*
- * Kick off a subshell to evaluate a tree.
+ * Called from trap.c when a SIGINT is received.  (If the user specifies
+ * that SIGINT is to be trapped or ignored using the trap builtin, then
+ * this routine is not called.)  Suppressint is nonzero when interrupts
+ * are held using the INTOFF macro.  (The test for iflag is just
+ * defensive programming.)
  */
 
 static void
-evalsubshell(const union node *n, int flags)
-{
-       struct job *jp;
-       int backgnd = (n->type == NBACKGND);
+onint(void) {
+       int i;
 
-       expredir(n->nredir.redirect);
-       jp = makejob(n, 1);
-       if (forkshell(jp, n, backgnd) == 0) {
-               if (backgnd)
-                       flags &=~ EV_TESTED;
-               redirect(n->nredir.redirect, 0);
-               evaltree(n->nredir.n, flags | EV_EXIT); /* never returns */
-       }
-       if (! backgnd) {
-               INTOFF;
-               exitstatus = waitforjob(jp);
-               INTON;
+       intpending = 0;
+       i = EXSIG;
+       if (gotsig[SIGINT - 1] && !trap[SIGINT]) {
+               if (!(rootshell && iflag)) {
+                       signal(SIGINT, SIG_DFL);
+                       raise(SIGINT);
+               }
+               i = EXINT;
        }
+       exraise(i);
+       /* NOTREACHED */
 }
 
-/*
- * Compute the names of the files in a redirection list.
- */
-
-static void fixredir(union node *n, const char *text, int err);
-
 static void
-expredir(union node *n)
+exvwarning(const char *msg, va_list ap)
 {
-       union node *redir;
+        FILE *errs;
 
-       for (redir = n ; redir ; redir = redir->nfile.next) {
-               struct arglist fn;
-               fn.lastp = &fn.list;
-               oexitstatus = exitstatus;
-               switch (redir->type) {
-               case NFROMTO:
-               case NFROM:
-               case NTO:
-               case NAPPEND:
-               case NTOOV:
-                       expandarg(redir->nfile.fname, &fn, EXP_TILDE | EXP_REDIR);
-                       redir->nfile.expfname = fn.list->text;
-                       break;
-               case NFROMFD:
-               case NTOFD:
-                       if (redir->ndup.vname) {
-                               expandarg(redir->ndup.vname, &fn, EXP_FULL | EXP_TILDE);
-                               fixredir(redir, fn.list->text, 1);
-                       }
-                       break;
-               }
-       }
+        errs = stderr;
+        fprintf(errs, "%s: ", arg0);
+        if (commandname) {
+                const char *fmt = (!iflag || parsefile->fd) ?
+                                       "%s: %d: " : "%s: ";
+                fprintf(errs, fmt, commandname, startlinno);
+        }
+        vfprintf(errs, msg, ap);
+        outcslow('\n', errs);
 }
 
-
 /*
- * Execute a command inside back quotes.  If it's a builtin command, we
- * want to save its output in a block obtained from malloc.  Otherwise
- * we fork off a subprocess and get the output of the command via a pipe.
- * Should be called with interrupts off.
+ * Exverror is called to raise the error exception.  If the second argument
+ * is not NULL then error prints an error message using printf style
+ * formatting.  It then raises the error exception.
  */
-
 static void
-evalbackcmd(union node *n, struct backcmd *result)
+exverror(int cond, const char *msg, va_list ap)
 {
-       int pip[2];
-       struct job *jp;
-       struct stackmark smark;         /* unnecessary */
+#ifdef DEBUG
+       if (msg) {
+               TRACE(("exverror(%d, \"", cond));
+               TRACEV((msg, ap));
+               TRACE(("\") pid=%d\n", getpid()));
+       } else
+               TRACE(("exverror(%d, NULL) pid=%d\n", cond, getpid()));
+       if (msg)
+#endif
+               exvwarning(msg, ap);
 
-       setstackmark(&smark);
-       result->fd = -1;
-       result->buf = NULL;
-       result->nleft = 0;
-       result->jp = NULL;
-       if (n == NULL) {
-               exitstatus = 0;
-               goto out;
-       }
-       exitstatus = 0;
-       if (pipe(pip) < 0)
-               error("Pipe call failed");
-       jp = makejob(n, 1);
-       if (forkshell(jp, n, FORK_NOJOB) == 0) {
-               FORCEINTON;
-               close(pip[0]);
-               if (pip[1] != 1) {
-                       close(1);
-                       dup_as_newfd(pip[1], 1);
-                       close(pip[1]);
-               }
-               eflag = 0;
-               evaltree(n, EV_EXIT);
-       }
-       close(pip[1]);
-       result->fd = pip[0];
-       result->jp = jp;
-out:
-       popstackmark(&smark);
-       TRACE(("evalbackcmd done: fd=%d buf=0x%x nleft=%d jp=0x%x\n",
-               result->fd, result->buf, result->nleft, result->jp));
+       flushall();
+       exraise(cond);
+       /* NOTREACHED */
 }
 
 
-/*
- * Execute a simple command.
- */
+static void
+sh_error(const char *msg, ...)
+{
+       va_list ap;
 
+       va_start(ap, msg);
+       exverror(EXERROR, msg, ap);
+       /* NOTREACHED */
+       va_end(ap);
+}
 
-/*
- * Builtin commands.  Builtin commands whose functions are closely
- * tied to evaluation are implemented here.
- */
+
+static void
+exerror(int cond, const char *msg, ...)
+{
+       va_list ap;
+
+       va_start(ap, msg);
+       exverror(cond, msg, ap);
+       /* NOTREACHED */
+       va_end(ap);
+}
 
 /*
- * No command given, or a bltin command with no arguments.  Set the
- * specified variables.
+ * error/warning routines for external builtins
  */
 
-int
-bltincmd(int argc, char **argv)
+static void
+sh_warnx(const char *fmt, ...)
 {
-       /*
-        * Preserve exitstatus of a previous possible redirection
-        * as POSIX mandates
-        */
-       return exitstatus;
+       va_list ap;
+
+       va_start(ap, fmt);
+       exvwarning(fmt, ap);
+       va_end(ap);
 }
 
 
 /*
- * Handle break and continue commands.  Break, continue, and return are
- * all handled by setting the evalskip flag.  The evaluation routines
- * above all check this flag, and if it is set they start skipping
- * commands rather than executing them.  The variable skipcount is
- * the number of loops to break/continue, or the number of function
- * levels to return.  (The latter is always 1.)  It should probably
- * be an error to break out of more loops than exist, but it isn't
- * in the standard shell so we don't make it one here.
+ * Return a string describing an error.  The returned string may be a
+ * pointer to a static buffer that will be overwritten on the next call.
+ * Action describes the operation that got the error.
  */
 
-static int
-breakcmd(int argc, char **argv)
+static const char *
+errmsg(int e, const char *em)
 {
-       int n = argc > 1 ? number(argv[1]) : 1;
+       if(e == ENOENT || e == ENOTDIR) {
 
-       if (n <= 0)
-               error("Illegal number: %s", argv[1]);
-       if (n > loopnest)
-               n = loopnest;
-       if (n > 0) {
-               evalskip = (**argv == 'c')? SKIPCONT : SKIPBREAK;
-               skipcount = n;
+               return em;
        }
-       return 0;
+       return strerror(e);
 }
 
 
+/*      eval.c  */
+
 /*
- * The return command.
+ * Evaluate a command.
  */
 
-static int
-returncmd(int argc, char **argv)
-{
-       int ret = argc > 1 ? number(argv[1]) : oexitstatus;
+/* flags in argument to evaltree */
+#define EV_EXIT 01              /* exit after evaluating tree */
+#define EV_TESTED 02            /* exit status is checked; ignore -e flag */
+#define EV_BACKCMD 04           /* command executing within back quotes */
 
-       if (funcnest) {
-               evalskip = SKIPFUNC;
-               skipcount = 1;
-               return ret;
-       }
-       else {
-               /* Do what ksh does; skip the rest of the file */
-               evalskip = SKIPFILE;
-               skipcount = 1;
-               return ret;
-       }
-}
 
+static void evalloop(union node *, int);
+static void evalfor(union node *, int);
+static void evalcase(union node *, int);
+static void evalsubshell(union node *, int);
+static void expredir(union node *);
+static void evalpipe(union node *, int);
+static void evalcommand(union node *, int);
+static int evalbltin(const struct builtincmd *, int, char **);
+static int evalfun(struct funcnode *, int, char **, int);
+static void prehash(union node *);
+static int bltincmd(int, char **);
 
-#ifndef CONFIG_FALSE
-static int
-false_main(int argc, char **argv)
-{
-       return 1;
-}
-#endif
 
-#ifndef CONFIG_TRUE
-static int
-true_main(int argc, char **argv)
-{
-       return 0;
-}
-#endif
+static const struct builtincmd bltin = {
+       "\0\0", bltincmd
+};
+
 
 /*
- * Controls whether the shell is interactive or not.
+ * Called to reset things after an exception.
  */
 
-static void setsignal(int signo);
-
-#ifdef CONFIG_ASH_MAIL
-static void chkmail(int silent);
-#endif
+/*
+ * The eval command.
+ */
 
-static void
-setinteractive(int on)
+static int
+evalcmd(int argc, char **argv)
 {
-       static int is_interactive;
-       static int do_banner=0;
+       char *p;
+       char *concat;
+       char **ap;
+
+       if (argc > 1) {
+               p = argv[1];
+               if (argc > 2) {
+                       STARTSTACKSTR(concat);
+                       ap = argv + 2;
+                       for (;;) {
+                               concat = stputs(p, concat);
+                               if ((p = *ap++) == NULL)
+                                       break;
+                               STPUTC(' ', concat);
+                       }
+                       STPUTC('\0', concat);
+                       p = grabstackstr(concat);
+               }
+               evalstring(p, ~SKIPEVAL);
 
-       if (on == is_interactive)
-               return;
-       setsignal(SIGINT);
-       setsignal(SIGQUIT);
-       setsignal(SIGTERM);
-#ifdef CONFIG_ASH_MAIL
-       chkmail(1);
-#endif
-       is_interactive = on;
-       if (do_banner==0 && is_interactive) {
-               /* Looks like they want an interactive shell */
-#ifndef CONFIG_FEATURE_SH_EXTRA_QUIET 
-               printf( "\n\n" BB_BANNER " Built-in shell (ash)\n");
-               printf( "Enter 'help' for a list of built-in commands.\n\n");
-#endif
-               do_banner=1;
        }
+       return exitstatus;
 }
 
-static void
-optschanged(void)
-{
-       setinteractive(iflag);
-       setjobctl(mflag);
-}
 
+/*
+ * Execute a command or commands contained in a string.
+ */
 
 static int
-execcmd(int argc, char **argv)
+evalstring(char *s, int mask)
 {
-       if (argc > 1) {
-               struct strlist *sp;
+       union node *n;
+       struct stackmark smark;
+       int skip;
 
-               iflag = 0;              /* exit on error */
-               mflag = 0;
-               optschanged();
-               for (sp = cmdenviron; sp ; sp = sp->next)
-                       setvareq(sp->text, VEXPORT|VSTACK);
-               shellexec(argv + 1, environment(), pathval(), 0);
-       }
-       return 0;
-}
+       setinputstring(s);
+       setstackmark(&smark);
 
-static void
-eprintlist(struct strlist *sp)
-{
-       for (; sp; sp = sp->next) {
-               out2fmt(" %s",sp->text);
+       skip = 0;
+       while ((n = parsecmd(0)) != NEOF) {
+               evaltree(n, 0);
+               popstackmark(&smark);
+               skip = evalskip;
+               if (skip)
+                       break;
        }
+       popfile();
+
+       skip &= mask;
+       evalskip = skip;
+       return skip;
 }
 
+
+
 /*
- * Exec a program.  Never returns.  If you change this routine, you may
- * have to change the find_command routine as well.
+ * Evaluate a parse tree.  The value is left in the global variable
+ * exitstatus.
  */
 
-static const char *pathopt;     /* set by padvance */
-
 static void
-shellexec(char **argv, char **envp, const char *path, int idx)
+evaltree(union node *n, int flags)
 {
-       char *cmdname;
-       int e;
-
-       if (strchr(argv[0], '/') != NULL) {
-               tryexec(argv[0], argv, envp);
-               e = errno;
-       } else {
-               e = ENOENT;
-               while ((cmdname = padvance(&path, argv[0])) != NULL) {
-                       if (--idx < 0 && pathopt == NULL) {
-                               tryexec(cmdname, argv, envp);
-                               if (errno != ENOENT && errno != ENOTDIR)
-                                       e = errno;
-                       }
-                       stunalloc(cmdname);
-               }
+       int checkexit = 0;
+       void (*evalfn)(union node *, int);
+       unsigned isor;
+       int status;
+       if (n == NULL) {
+               TRACE(("evaltree(NULL) called\n"));
+               goto out;
        }
-
-       /* Map to POSIX errors */
-       switch (e) {
-       case EACCES:
-               exerrno = 126;
+       TRACE(("pid %d, evaltree(%p: %d, %d) called\n",
+           getpid(), n, n->type, flags));
+       switch (n->type) {
+       default:
+#ifdef DEBUG
+               out1fmt("Node type = %d\n", n->type);
+               fflush(stdout);
                break;
-       case ENOENT:
-               exerrno = 127;
+#endif
+       case NNOT:
+               evaltree(n->nnot.com, EV_TESTED);
+               status = !exitstatus;
+               goto setstatus;
+       case NREDIR:
+               expredir(n->nredir.redirect);
+               status = redirectsafe(n->nredir.redirect, REDIR_PUSH);
+               if (!status) {
+                       evaltree(n->nredir.n, flags & EV_TESTED);
+                       status = exitstatus;
+               }
+               popredir(0);
+               goto setstatus;
+       case NCMD:
+               evalfn = evalcommand;
+checkexit:
+               if (eflag && !(flags & EV_TESTED))
+                       checkexit = ~0;
+               goto calleval;
+       case NFOR:
+               evalfn = evalfor;
+               goto calleval;
+       case NWHILE:
+       case NUNTIL:
+               evalfn = evalloop;
+               goto calleval;
+       case NSUBSHELL:
+       case NBACKGND:
+               evalfn = evalsubshell;
+               goto calleval;
+       case NPIPE:
+               evalfn = evalpipe;
+               goto checkexit;
+       case NCASE:
+               evalfn = evalcase;
+               goto calleval;
+       case NAND:
+       case NOR:
+       case NSEMI:
+#if NAND + 1 != NOR
+#error NAND + 1 != NOR
+#endif
+#if NOR + 1 != NSEMI
+#error NOR + 1 != NSEMI
+#endif
+               isor = n->type - NAND;
+               evaltree(
+                       n->nbinary.ch1,
+                       (flags | ((isor >> 1) - 1)) & EV_TESTED
+               );
+               if (!exitstatus == isor)
+                       break;
+               if (!evalskip) {
+                       n = n->nbinary.ch2;
+evaln:
+                       evalfn = evaltree;
+calleval:
+                       evalfn(n, flags);
+                       break;
+               }
                break;
-       default:
-               exerrno = 2;
+       case NIF:
+               evaltree(n->nif.test, EV_TESTED);
+               if (evalskip)
+                       break;
+               if (exitstatus == 0) {
+                       n = n->nif.ifpart;
+                       goto evaln;
+               } else if (n->nif.elsepart) {
+                       n = n->nif.elsepart;
+                       goto evaln;
+               }
+               goto success;
+       case NDEFUN:
+               defun(n->narg.text, n->narg.next);
+success:
+               status = 0;
+setstatus:
+               exitstatus = status;
                break;
        }
-       exerror(EXEXEC, "%s: %s", argv[0], errmsg(e, E_EXEC));
-       /* NOTREACHED */
-}
-
-/*
- * Clear traps on a fork.
- */
-static void
-clear_traps(void)
-{
-       char **tp;
+out:
+       if ((checkexit & exitstatus))
+               evalskip |= SKIPEVAL;
+       else if (pendingsigs && dotrap())
+               goto exexit;
 
-       for (tp = trap ; tp < &trap[NSIG] ; tp++) {
-               if (*tp && **tp) {      /* trap not NULL or SIG_IGN */
-                       INTOFF;
-                       ckfree(*tp);
-                       *tp = NULL;
-                       if (tp != &trap[0])
-                               setsignal(tp - trap);
-                       INTON;
-               }
+       if (flags & EV_EXIT) {
+exexit:
+               exraise(EXEXIT);
        }
 }
 
 
-static void
-initshellproc(void)
-{
-
-#ifdef CONFIG_ASH_ALIAS
-      /* from alias.c: */
-      {
-             rmaliases();
-      }
+#if !defined(__alpha__) || (defined(__GNUC__) && __GNUC__ >= 3)
+static
 #endif
-      /* from eval.c: */
-      {
-             exitstatus = 0;
-      }
+void evaltreenr(union node *, int) __attribute__ ((alias("evaltree"),__noreturn__));
 
-      /* from exec.c: */
-      {
-             deletefuncs();
-      }
 
-      /* from jobs.c: */
-      {
-             backgndpid = -1;
-#ifdef CONFIG_ASH_JOB_CONTROL
-             jobctl = 0;
-#endif
-      }
+static void
+evalloop(union node *n, int flags)
+{
+       int status;
 
-      /* from options.c: */
-      {
-             int i;
+       loopnest++;
+       status = 0;
+       flags &= EV_TESTED;
+       for (;;) {
+               int i;
 
-             for (i = 0; i < NOPTS; i++)
-                     optent_val(i) = 0;
-             optschanged();
+               evaltree(n->nbinary.ch1, EV_TESTED);
+               if (evalskip) {
+skipping:         if (evalskip == SKIPCONT && --skipcount <= 0) {
+                               evalskip = 0;
+                               continue;
+                       }
+                       if (evalskip == SKIPBREAK && --skipcount <= 0)
+                               evalskip = 0;
+                       break;
+               }
+               i = exitstatus;
+               if (n->type != NWHILE)
+                       i = !i;
+               if (i != 0)
+                       break;
+               evaltree(n->nbinary.ch2, flags);
+               status = exitstatus;
+               if (evalskip)
+                       goto skipping;
+       }
+       loopnest--;
+       exitstatus = status;
+}
 
-      }
 
-      /* from redir.c: */
-      {
-             clearredir();
-      }
 
-      /* from trap.c: */
-      {
-             char *sm;
+static void
+evalfor(union node *n, int flags)
+{
+       struct arglist arglist;
+       union node *argp;
+       struct strlist *sp;
+       struct stackmark smark;
 
-             clear_traps();
-             for (sm = sigmode ; sm < sigmode + NSIG - 1; sm++) {
-                     if (*sm == S_IGN)
-                             *sm = S_HARD_IGN;
-             }
-      }
+       setstackmark(&smark);
+       arglist.lastp = &arglist.list;
+       for (argp = n->nfor.args ; argp ; argp = argp->narg.next) {
+               expandarg(argp, &arglist, EXP_FULL | EXP_TILDE | EXP_RECORD);
+               /* XXX */
+               if (evalskip)
+                       goto out;
+       }
+       *arglist.lastp = NULL;
 
-      /* from var.c: */
-      {
-             shprocvar();
-      }
+       exitstatus = 0;
+       loopnest++;
+       flags &= EV_TESTED;
+       for (sp = arglist.list ; sp ; sp = sp->next) {
+               setvar(n->nfor.var, sp->text, 0);
+               evaltree(n->nfor.body, flags);
+               if (evalskip) {
+                       if (evalskip == SKIPCONT && --skipcount <= 0) {
+                               evalskip = 0;
+                               continue;
+                       }
+                       if (evalskip == SKIPBREAK && --skipcount <= 0)
+                               evalskip = 0;
+                       break;
+               }
+       }
+       loopnest--;
+out:
+       popstackmark(&smark);
 }
 
-static int preadbuffer(void);
-static void pushfile (void);
 
-/*
- * Read a character from the script, returning PEOF on end of file.
- * Nul characters in the input are silently discarded.
- */
 
-#ifndef CONFIG_ASH_OPTIMIZE_FOR_SIZE
-#define pgetc_macro()   (--parsenleft >= 0? *parsenextc++ : preadbuffer())
-static int
-pgetc(void)
-{
-       return pgetc_macro();
-}
-#else
-static int
-pgetc_macro(void)
+static void
+evalcase(union node *n, int flags)
 {
-       return --parsenleft >= 0? *parsenextc++ : preadbuffer();
-}
+       union node *cp;
+       union node *patp;
+       struct arglist arglist;
+       struct stackmark smark;
 
-static inline int
-pgetc(void)
-{
-       return pgetc_macro();
+       setstackmark(&smark);
+       arglist.lastp = &arglist.list;
+       expandarg(n->ncase.expr, &arglist, EXP_TILDE);
+       exitstatus = 0;
+       for (cp = n->ncase.cases ; cp && evalskip == 0 ; cp = cp->nclist.next) {
+               for (patp = cp->nclist.pattern ; patp ; patp = patp->narg.next) {
+                       if (casematch(patp, arglist.list->text)) {
+                               if (evalskip == 0) {
+                                       evaltree(cp->nclist.body, flags);
+                               }
+                               goto out;
+                       }
+               }
+       }
+out:
+       popstackmark(&smark);
 }
-#endif
+
 
 
 /*
- * Undo the last call to pgetc.  Only one character may be pushed back.
- * PEOF may be pushed back.
+ * Kick off a subshell to evaluate a tree.
  */
 
-static void pungetc(void) 
-{
-       parsenleft++;
-       parsenextc--;
-}
-
-
 static void
-popfile(void)
+evalsubshell(union node *n, int flags)
 {
-       struct parsefile *pf = parsefile;
+       struct job *jp;
+       int backgnd = (n->type == NBACKGND);
+       int status;
 
+       expredir(n->nredir.redirect);
+       if (!backgnd && flags & EV_EXIT && !trap[0])
+               goto nofork;
        INTOFF;
-       if (pf->fd >= 0)
-               close(pf->fd);
-       if (pf->buf)
-               ckfree(pf->buf);
-       while (pf->strpush)
-               popstring();
-       parsefile = pf->prev;
-       ckfree(pf);
-       parsenleft = parsefile->nleft;
-       parselleft = parsefile->lleft;
-       parsenextc = parsefile->nextc;
-       plinno = parsefile->linno;
+       jp = makejob(n, 1);
+       if (forkshell(jp, n, backgnd) == 0) {
+               INTON;
+               flags |= EV_EXIT;
+               if (backgnd)
+                       flags &=~ EV_TESTED;
+nofork:
+               redirect(n->nredir.redirect, 0);
+               evaltreenr(n->nredir.n, flags);
+               /* never returns */
+       }
+       status = 0;
+       if (! backgnd)
+               status = waitforjob(jp);
+       exitstatus = status;
        INTON;
 }
 
 
-/*
- * Return to top level.
- */
-
-static void
-popallfiles(void)
-{
-       while (parsefile != &basepf)
-               popfile();
-}
 
 /*
- * Close the file(s) that the shell is reading commands from.  Called
- * after a fork is done.
+ * Compute the names of the files in a redirection list.
  */
 
-static void closescript(void) 
+static void
+expredir(union node *n)
 {
-       popallfiles();
-       if (parsefile->fd > 0) {
-               close(parsefile->fd);
-               parsefile->fd = 0;
-       }
-}
-
+       union node *redir;
 
-/*
- * Like setinputfile, but takes an open file descriptor.  Call this with
- * interrupts off.
- */
-
-static void setinputfd(int fd, int push)
-{
-       (void) fcntl(fd, F_SETFD, FD_CLOEXEC);
-       if (push) {
-               pushfile();
-               parsefile->buf = 0;
-       } else {
-               closescript();
-               while (parsefile->strpush)
-                       popstring();
+       for (redir = n ; redir ; redir = redir->nfile.next) {
+               struct arglist fn;
+               fn.lastp = &fn.list;
+               switch (redir->type) {
+               case NFROMTO:
+               case NFROM:
+               case NTO:
+               case NCLOBBER:
+               case NAPPEND:
+                       expandarg(redir->nfile.fname, &fn, EXP_TILDE | EXP_REDIR);
+                       redir->nfile.expfname = fn.list->text;
+                       break;
+               case NFROMFD:
+               case NTOFD:
+                       if (redir->ndup.vname) {
+                               expandarg(redir->ndup.vname, &fn, EXP_FULL | EXP_TILDE);
+                               fixredir(redir, fn.list->text, 1);
+                       }
+                       break;
+               }
        }
-       parsefile->fd = fd;
-       if (parsefile->buf == NULL)
-               parsefile->buf = xmalloc(BUFSIZ);
-       parselleft = parsenleft = 0;
-       plinno = 1;
 }
 
 
+
 /*
- * Set the input to take input from a file.  If push is set, push the
- * old input onto the stack first.
+ * Evaluate a pipeline.  All the processes in the pipeline are children
+ * of the process creating the pipeline.  (This differs from some versions
+ * of the shell, which make the last process in a pipeline the parent
+ * of all the rest.)
  */
 
 static void
-setinputfile(const char *fname, int push)
+evalpipe(union node *n, int flags)
 {
-       int fd;
-       int myfileno2;
+       struct job *jp;
+       struct nodelist *lp;
+       int pipelen;
+       int prevfd;
+       int pip[2];
 
+       TRACE(("evalpipe(0x%lx) called\n", (long)n));
+       pipelen = 0;
+       for (lp = n->npipe.cmdlist ; lp ; lp = lp->next)
+               pipelen++;
+       flags |= EV_EXIT;
        INTOFF;
-       if ((fd = open(fname, O_RDONLY)) < 0)
-               error("Can't open %s", fname);
-       if (fd < 10) {
-               myfileno2 = dup_as_newfd(fd, 10);
-               close(fd);
-               if (myfileno2 < 0)
-                       error("Out of file descriptors");
-               fd = myfileno2;
+       jp = makejob(n, pipelen);
+       prevfd = -1;
+       for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
+               prehash(lp->n);
+               pip[1] = -1;
+               if (lp->next) {
+                       if (pipe(pip) < 0) {
+                               close(prevfd);
+                               sh_error("Pipe call failed");
+                       }
+               }
+               if (forkshell(jp, lp->n, n->npipe.backgnd) == 0) {
+                       INTON;
+                       if (pip[1] >= 0) {
+                               close(pip[0]);
+                       }
+                       if (prevfd > 0) {
+                               dup2(prevfd, 0);
+                               close(prevfd);
+                       }
+                       if (pip[1] > 1) {
+                               dup2(pip[1], 1);
+                               close(pip[1]);
+                       }
+                       evaltreenr(lp->n, flags);
+                       /* never returns */
+               }
+               if (prevfd >= 0)
+                       close(prevfd);
+               prevfd = pip[0];
+               close(pip[1]);
+       }
+       if (n->npipe.backgnd == 0) {
+               exitstatus = waitforjob(jp);
+               TRACE(("evalpipe:  job done exit status %d\n", exitstatus));
        }
-       setinputfd(fd, push);
        INTON;
 }
 
 
+
+/*
+ * Execute a command inside back quotes.  If it's a builtin command, we
+ * want to save its output in a block obtained from malloc.  Otherwise
+ * we fork off a subprocess and get the output of the command via a pipe.
+ * Should be called with interrupts off.
+ */
+
 static void
-tryexec(char *cmd, char **argv, char **envp)
+evalbackcmd(union node *n, struct backcmd *result)
 {
-       int e;
+       int saveherefd;
 
-#ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
-       char *name = cmd;
-       char** argv_l=argv;
-       int argc_l;
-#ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
-       name = get_last_path_component(name);
-#endif
-       argv_l=envp;
-       for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++)
-               putenv(*argv_l);
-       argv_l=argv;
-       for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++)
-       optind = 1;
-       run_applet_by_name(name, argc_l, argv);
-#endif
-       execve(cmd, argv, envp);
-       e = errno;
-       if (e == ENOEXEC) {
-               INTOFF;
-               initshellproc();
-               setinputfile(cmd, 0);
-               commandname = arg0 = xstrdup(argv[0]);
-               setparam(argv + 1);
-               exraise(EXSHELLPROC);
+       result->fd = -1;
+       result->buf = NULL;
+       result->nleft = 0;
+       result->jp = NULL;
+       if (n == NULL) {
+               goto out;
        }
-       errno = e;
-}
-
-static char *commandtext (const union node *);
-
-/*
- * Do a path search.  The variable path (passed by reference) should be
- * set to the start of the path before the first call; padvance will update
- * this value as it proceeds.  Successive calls to padvance will return
- * the possible path expansions in sequence.  If an option (indicated by
- * a percent sign) appears in the path entry then the global variable
- * pathopt will be set to point to it; otherwise pathopt will be set to
- * NULL.
- */
 
-static const char *pathopt;
+       saveherefd = herefd;
+       herefd = -1;
 
-static void growstackblock(void);
+       {
+               int pip[2];
+               struct job *jp;
 
+               if (pipe(pip) < 0)
+                       sh_error("Pipe call failed");
+               jp = makejob(n, 1);
+               if (forkshell(jp, n, FORK_NOJOB) == 0) {
+                       FORCEINTON;
+                       close(pip[0]);
+                       if (pip[1] != 1) {
+                               close(1);
+                               copyfd(pip[1], 1);
+                               close(pip[1]);
+                       }
+                       eflag = 0;
+                       evaltreenr(n, EV_EXIT);
+                       /* NOTREACHED */
+               }
+               close(pip[1]);
+               result->fd = pip[0];
+               result->jp = jp;
+       }
+       herefd = saveherefd;
+out:
+       TRACE(("evalbackcmd done: fd=%d buf=0x%x nleft=%d jp=0x%x\n",
+               result->fd, result->buf, result->nleft, result->jp));
+}
 
-static char *
-padvance(const char **path, const char *name)
+#ifdef CONFIG_ASH_CMDCMD
+static inline char **
+parse_command_args(char **argv, const char **path)
 {
-       const char *p;
-       char *q;
-       const char *start;
-       int len;
+       char *cp, c;
 
-       if (*path == NULL)
-               return NULL;
-       start = *path;
-       for (p = start ; *p && *p != ':' && *p != '%' ; p++);
-       len = p - start + strlen(name) + 2;     /* "2" is for '/' and '\0' */
-       while (stackblocksize() < len)
-               growstackblock();
-       q = stackblock();
-       if (p != start) {
-               memcpy(q, start, p - start);
-               q += p - start;
-               *q++ = '/';
-       }
-       strcpy(q, name);
-       pathopt = NULL;
-       if (*p == '%') {
-               pathopt = ++p;
-               while (*p && *p != ':')  p++;
+       for (;;) {
+               cp = *++argv;
+               if (!cp)
+                       return 0;
+               if (*cp++ != '-')
+                       break;
+               if (!(c = *cp++))
+                       break;
+               if (c == '-' && !*cp) {
+                       argv++;
+                       break;
+               }
+               do {
+                       switch (c) {
+                       case 'p':
+                               *path = defpath;
+                               break;
+                       default:
+                               /* run 'typecmd' for other options */
+                               return 0;
+                       }
+               } while ((c = *cp++));
        }
-       if (*p == ':')
-               *path = p + 1;
-       else
-               *path = NULL;
-       return stalloc(len);
+       return argv;
 }
+#endif
 
-/*
- * Wrapper around strcmp for qsort/bsearch/...
- */
-static int
-pstrcmp(const void *a, const void *b)
+static inline int
+isassignment(const char *p)
 {
-       return strcmp((const char *) a, (*(const char *const *) b) + 1);
+       const char *q = endofname(p);
+       if (p == q)
+               return 0;
+       return *q == '=';
 }
 
+#ifdef CONFIG_ASH_EXPAND_PRMT
+static const char *expandstr(const char *ps);
+#else
+#define expandstr(s) s
+#endif
+
 /*
- * Find a keyword is in a sorted array.
+ * Execute a simple command.
  */
 
-static const char *const *
-findkwd(const char *s)
+static void
+evalcommand(union node *cmd, int flags)
 {
-       return  bsearch(s, tokname_array + KWDOFFSET,
-                                       (sizeof(tokname_array)/sizeof(const char *)) - KWDOFFSET,
-                                       sizeof(const char *), pstrcmp);
-}
+       struct stackmark smark;
+       union node *argp;
+       struct arglist arglist;
+       struct arglist varlist;
+       char **argv;
+       int argc;
+       const struct strlist *sp;
+       struct cmdentry cmdentry;
+       struct job *jp;
+       char *lastarg;
+       const char *path;
+       int spclbltin;
+       int cmd_is_exec;
+       int status;
+       char **nargv;
+       struct builtincmd *bcmd;
+       int pseudovarflag = 0;
 
+       /* First expand the arguments. */
+       TRACE(("evalcommand(0x%lx, %d) called\n", (long)cmd, flags));
+       setstackmark(&smark);
+       back_exitstatus = 0;
 
-/*** Command hashing code ***/
+       cmdentry.cmdtype = CMDBUILTIN;
+       cmdentry.u.cmd = &bltin;
+       varlist.lastp = &varlist.list;
+       *varlist.lastp = NULL;
+       arglist.lastp = &arglist.list;
+       *arglist.lastp = NULL;
 
+       argc = 0;
+       if (cmd->ncmd.args)
+       {
+               bcmd = find_builtin(cmd->ncmd.args->narg.text);
+               pseudovarflag = bcmd && IS_BUILTIN_ASSIGN(bcmd);
+       }
 
-static int
-hashcmd(int argc, char **argv)
-{
-       struct tblentry **pp;
-       struct tblentry *cmdp;
-       int c;
-       int verbose;
-       struct cmdentry entry;
-       char *name;
-#ifdef CONFIG_ASH_ALIAS
-       const struct alias *ap;
-#endif
+       for (argp = cmd->ncmd.args; argp; argp = argp->narg.next) {
+               struct strlist **spp;
 
-       verbose = 0;
-       while ((c = nextopt("rvV")) != '\0') {
-               if (c == 'r') {
-                       clearcmdentry(0);
-                       return 0;
-               } else if (c == 'v' || c == 'V') {
-                       verbose = c;
-               }
+               spp = arglist.lastp;
+               if (pseudovarflag && isassignment(argp->narg.text))
+                       expandarg(argp, &arglist, EXP_VARTILDE);
+               else
+                       expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
+
+               for (sp = *spp; sp; sp = sp->next)
+                       argc++;
        }
-       if (*argptr == NULL) {
-               for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
-                       for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
-                               if (cmdp->cmdtype != CMDBUILTIN) {
-                                       printentry(cmdp, verbose);
+
+       argv = nargv = stalloc(sizeof (char *) * (argc + 1));
+       for (sp = arglist.list ; sp ; sp = sp->next) {
+               TRACE(("evalcommand arg: %s\n", sp->text));
+               *nargv++ = sp->text;
+       }
+       *nargv = NULL;
+
+       lastarg = NULL;
+       if (iflag && funcnest == 0 && argc > 0)
+               lastarg = nargv[-1];
+
+       preverrout_fd = 2;
+       expredir(cmd->ncmd.redirect);
+       status = redirectsafe(cmd->ncmd.redirect, REDIR_PUSH|REDIR_SAVEFD2);
+
+       path = vpath.text;
+       for (argp = cmd->ncmd.assign; argp; argp = argp->narg.next) {
+               struct strlist **spp;
+               char *p;
+
+               spp = varlist.lastp;
+               expandarg(argp, &varlist, EXP_VARTILDE);
+
+               /*
+                * Modify the command lookup path, if a PATH= assignment
+                * is present
+                */
+               p = (*spp)->text;
+               if (varequal(p, path))
+                       path = p;
+       }
+
+       /* Print the command if xflag is set. */
+       if (xflag) {
+               int n;
+               const char *p = " %s";
+
+               p++;
+               dprintf(preverrout_fd, p, expandstr(ps4val()));
+
+               sp = varlist.list;
+               for(n = 0; n < 2; n++) {
+                       while (sp) {
+                               dprintf(preverrout_fd, p, sp->text);
+                               sp = sp->next;
+                               if(*p == '%') {
+                                       p--;
                                }
                        }
+                       sp = arglist.list;
                }
-               return 0;
+               full_write(preverrout_fd, "\n", 1);
        }
-       c = 0;
-       while ((name = *argptr++) != NULL) {
-               if ((cmdp = cmdlookup(name, 0)) != NULL
-                && (cmdp->cmdtype == CMDNORMAL
-                    || (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0)))
-                       delete_cmd_entry();
-#ifdef CONFIG_ASH_ALIAS
-       /* Then look at the aliases */
-               if ((ap = *__lookupalias(name)) != NULL) {
-                       if (verbose=='v')
-                               printf("%s is an alias for %s\n", name, ap->val);
-                       else
-                               printalias(ap);
-                       continue;
-               }
-#endif
-                       /* First look at the keywords */
-               if (findkwd(name)!=0) {
-                       if (verbose=='v')
-                               printf("%s is a shell keyword\n", name);
-                       else
-                               puts(name);
-                       continue;
-               }
-
-               find_command(name, &entry, DO_ERR, pathval());
-               if (entry.cmdtype == CMDUNKNOWN) c = 1;
-               else if (verbose) {
-                       cmdp = cmdlookup(name, 0);
-                       if (cmdp) printentry(cmdp, verbose=='v');
-                       flushall();
-               }
-       }
-       return c;
-}
-
-static void
-printentry(struct tblentry *cmdp, int verbose)
-{
-       int idx;
-       const char *path;
-       char *name;
-
-       printf("%s%s", cmdp->cmdname, (verbose ? " is " : ""));
-       if (cmdp->cmdtype == CMDNORMAL) {
-               idx = cmdp->param.index;
-               path = pathval();
-               do {
-                       name = padvance(&path, cmdp->cmdname);
-                       stunalloc(name);
-               } while (--idx >= 0);
-               if(verbose)
-                       out1str(name);
-       } else if (cmdp->cmdtype == CMDBUILTIN) {
-               if(verbose)
-                       out1str("a shell builtin");
-       } else if (cmdp->cmdtype == CMDFUNCTION) {
-               if (verbose) {
-                       INTOFF;
-                       out1str("a function\n");
-                       name = commandtext(cmdp->param.func);
-                       printf("%s() {\n %s\n}", cmdp->cmdname, name);
-                       ckfree(name);
-                       INTON;
-               }
-#ifdef DEBUG
-       } else {
-               error("internal error: cmdtype %d", cmdp->cmdtype);
-#endif
-       }
-       puts(cmdp->rehash ? "*" : nullstr);
-}
-
 
+       cmd_is_exec = 0;
+       spclbltin = -1;
 
-/*** List the available builtins ***/
+       /* Now locate the command. */
+       if (argc) {
+               const char *oldpath;
+               int cmd_flag = DO_ERR;
 
+               path += 5;
+               oldpath = path;
+               for (;;) {
+                       find_command(argv[0], &cmdentry, cmd_flag, path);
+                       if (cmdentry.cmdtype == CMDUNKNOWN) {
+                               status = 127;
+                               flusherr();
+                               goto bail;
+                       }
 
-static int helpcmd(int argc, char** argv)
-{
-       int col, i;
+                       /* implement bltin and command here */
+                       if (cmdentry.cmdtype != CMDBUILTIN)
+                               break;
+                       if (spclbltin < 0)
+                               spclbltin = IS_BUILTIN_SPECIAL(cmdentry.u.cmd);
+                       if (cmdentry.u.cmd == EXECCMD)
+                               cmd_is_exec++;
+#ifdef CONFIG_ASH_CMDCMD
+                       if (cmdentry.u.cmd == COMMANDCMD) {
 
-       printf("\nBuilt-in commands:\n-------------------\n");
-       for (col=0, i=0; i < NUMBUILTINS; i++) {
-               col += printf("%c%s", ((col == 0) ? '\t' : ' '),
-                               builtincmds[i].name+1);
-               if (col > 60) {
-                       printf("\n");
-                       col = 0;
+                               path = oldpath;
+                               nargv = parse_command_args(argv, &path);
+                               if (!nargv)
+                                       break;
+                               argc -= nargv - argv;
+                               argv = nargv;
+                               cmd_flag |= DO_NOFUNC;
+                       } else
+#endif
+                               break;
                }
        }
-#ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
-       {
-               extern const struct BB_applet applets[];
-               extern const size_t NUM_APPLETS;
-
-               for (i=0; i < NUM_APPLETS; i++) {
 
-                       col += printf("%c%s", ((col == 0) ? '\t' : ' '),
-                                       applets[i].name);
-                       if (col > 60) {
-                               printf("\n");
-                               col = 0;
-                       }
-               }
+       if (status) {
+               /* We have a redirection error. */
+               if (spclbltin > 0)
+                       exraise(EXERROR);
+bail:
+               exitstatus = status;
+               goto out;
        }
-#endif
-       printf("\n\n");
-       return EXIT_SUCCESS;
-}
-
-/*
- * Resolve a command name.  If you change this routine, you may have to
- * change the shellexec routine as well.
- */
-
-static int prefix (const char *, const char *);
-
-static void
-find_command(const char *name, struct cmdentry *entry, int act, const char *path)
-{
-       struct tblentry *cmdp;
-       int idx;
-       int prev;
-       char *fullname;
-       struct stat statb;
-       int e;
-       int bltin;
-       int firstchange;
-       int updatetbl;
-       int regular;
-       struct builtincmd *bcmd;
 
-       /* If name contains a slash, don't use the hash table */
-       if (strchr(name, '/') != NULL) {
-               if (act & DO_ABS) {
-                       while (stat(name, &statb) < 0) {
-                               if (errno != ENOENT && errno != ENOTDIR)
-                                       e = errno;
-                               entry->cmdtype = CMDUNKNOWN;
-                               entry->u.index = -1;
-                               return;
+       /* Execute the command. */
+       switch (cmdentry.cmdtype) {
+       default:
+               /* Fork off a child process if necessary. */
+               if (!(flags & EV_EXIT) || trap[0]) {
+                       INTOFF;
+                       jp = makejob(cmd, 1);
+                       if (forkshell(jp, cmd, FORK_FG) != 0) {
+                               exitstatus = waitforjob(jp);
+                               INTON;
+                               break;
                        }
-                       entry->cmdtype = CMDNORMAL;
-                       entry->u.index = -1;
-                       return;
+                       FORCEINTON;
                }
-               entry->cmdtype = CMDNORMAL;
-               entry->u.index = 0;
-               return;
-       }
-
-       updatetbl = 1;
-       if (act & DO_BRUTE) {
-               firstchange = path_change(path, &bltin);
-       } else {
-               bltin = builtinloc;
-               firstchange = 9999;
-       }
+               listsetvar(varlist.list, VEXPORT|VSTACK);
+               shellexec(argv, path, cmdentry.u.index);
+               /* NOTREACHED */
 
-       /* If name is in the table, and not invalidated by cd, we're done */
-       if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->rehash == 0) {
-               if (cmdp->cmdtype == CMDFUNCTION) {
-                       if (act & DO_NOFUN) {
-                               updatetbl = 0;
-                       } else {
-                               goto success;
+       case CMDBUILTIN:
+               cmdenviron = varlist.list;
+               if (cmdenviron) {
+                       struct strlist *list = cmdenviron;
+                       int i = VNOSET;
+                       if (spclbltin > 0 || argc == 0) {
+                               i = 0;
+                               if (cmd_is_exec && argc > 1)
+                                       i = VEXPORT;
                        }
-               } else if (act & DO_BRUTE) {
-                       if ((cmdp->cmdtype == CMDNORMAL &&
-                            cmdp->param.index >= firstchange) ||
-                           (cmdp->cmdtype == CMDBUILTIN &&
-                            ((builtinloc < 0 && bltin >= 0) ?
-                             bltin : builtinloc) >= firstchange)) {
-                               /* need to recompute the entry */
-                       } else {
-                               goto success;
+                       listsetvar(list, i);
+               }
+               if (evalbltin(cmdentry.u.cmd, argc, argv)) {
+                       int exit_status;
+                       int i, j;
+
+                       i = exception;
+                       if (i == EXEXIT)
+                               goto raise;
+
+                       exit_status = 2;
+                       j = 0;
+                       if (i == EXINT)
+                               j = SIGINT;
+                       if (i == EXSIG)
+                               j = pendingsigs;
+                       if (j)
+                               exit_status = j + 128;
+                       exitstatus = exit_status;
+
+                       if (i == EXINT || spclbltin > 0) {
+raise:
+                               longjmp(handler->loc, 1);
                        }
-               } else {
-                       goto success;
+                       FORCEINTON;
                }
-       }
-
-       bcmd = find_builtin(name);
-       regular = bcmd && IS_BUILTIN_REGULAR(bcmd);
+               break;
 
-       if (regular) {
-               if (cmdp && (cmdp->cmdtype == CMDBUILTIN)) {
-                       goto success;
-               }
-       } else if (act & DO_BRUTE) {
-               if (firstchange == 0) {
-                       updatetbl = 0;
-               }
+       case CMDFUNCTION:
+               listsetvar(varlist.list, 0);
+               if (evalfun(cmdentry.u.func, argc, argv, flags))
+                       goto raise;
+               break;
        }
 
-       /* If %builtin not in path, check for builtin next */
-       if (regular || (bltin < 0 && bcmd)) {
-builtin:
-               if (!updatetbl) {
-                       entry->cmdtype = CMDBUILTIN;
-                       entry->u.cmd = bcmd;
-                       return;
-               }
-               INTOFF;
-               cmdp = cmdlookup(name, 1);
-               cmdp->cmdtype = CMDBUILTIN;
-               cmdp->param.cmd = bcmd;
-               INTON;
-               goto success;
-       }
+out:
+       popredir(cmd_is_exec);
+       if (lastarg)
+               /* dsl: I think this is intended to be used to support
+                * '_' in 'vi' command mode during line editing...
+                * However I implemented that within libedit itself.
+                */
+               setvar("_", lastarg, 0);
+       popstackmark(&smark);
+}
 
-       /* We have to search path. */
-       prev = -1;              /* where to start */
-       if (cmdp && cmdp->rehash) {     /* doing a rehash */
-               if (cmdp->cmdtype == CMDBUILTIN)
-                       prev = builtinloc;
-               else
-                       prev = cmdp->param.index;
-       }
+static int
+evalbltin(const struct builtincmd *cmd, int argc, char **argv) {
+       char *volatile savecmdname;
+       struct jmploc *volatile savehandler;
+       struct jmploc jmploc;
+       int i;
 
-       e = ENOENT;
-       idx = -1;
-loop:
-       while ((fullname = padvance(&path, name)) != NULL) {
-               stunalloc(fullname);
-               idx++;
-               if (idx >= firstchange) {
-                       updatetbl = 0;
-               }
-               if (pathopt) {
-                       if (prefix("builtin", pathopt)) {
-                               if ((bcmd = find_builtin(name))) {
-                                       goto builtin;
-                               }
-                               continue;
-                       } else if (!(act & DO_NOFUN) &&
-                                  prefix("func", pathopt)) {
-                               /* handled below */
-                       } else {
-                               continue;       /* ignore unimplemented options */
-                       }
-               }
-               /* if rehash, don't redo absolute path names */
-               if (fullname[0] == '/' && idx <= prev &&
-                   idx < firstchange) {
-                       if (idx < prev)
-                               continue;
-                       TRACE(("searchexec \"%s\": no change\n", name));
-                       goto success;
-               }
-               while (stat(fullname, &statb) < 0) {
-                       if (errno != ENOENT && errno != ENOTDIR)
-                               e = errno;
-                       goto loop;
-               }
-               e = EACCES;     /* if we fail, this will be the error */
-               if (!S_ISREG(statb.st_mode))
-                       continue;
-               if (pathopt) {          /* this is a %func directory */
-                       stalloc(strlen(fullname) + 1);
-                       readcmdfile(fullname);
-                       if ((cmdp = cmdlookup(name, 0)) == NULL || cmdp->cmdtype != CMDFUNCTION)
-                               error("%s not defined in %s", name, fullname);
-                       stunalloc(fullname);
-                       goto success;
-               }
-               TRACE(("searchexec \"%s\" returns \"%s\"\n", name, fullname));
-               /* If we aren't called with DO_BRUTE and cmdp is set, it must
-                  be a function and we're being called with DO_NOFUN */
-               if (!updatetbl) {
-                       entry->cmdtype = CMDNORMAL;
-                       entry->u.index = idx;
-                       return;
-               }
-               INTOFF;
-               cmdp = cmdlookup(name, 1);
-               cmdp->cmdtype = CMDNORMAL;
-               cmdp->param.index = idx;
-               INTON;
-               goto success;
-       }
+       savecmdname = commandname;
+       if ((i = setjmp(jmploc.loc)))
+               goto cmddone;
+       savehandler = handler;
+       handler = &jmploc;
+       commandname = argv[0];
+       argptr = argv + 1;
+       optptr = NULL;                  /* initialize nextopt */
+       exitstatus = (*cmd->builtin)(argc, argv);
+       flushall();
+cmddone:
+       exitstatus |= ferror(stdout);
+       clearerr(stdout);
+       commandname = savecmdname;
+       exsig = 0;
+       handler = savehandler;
 
-       /* We failed.  If there was an entry for this command, delete it */
-       if (cmdp && updatetbl)
-               delete_cmd_entry();
-       if (act & DO_ERR)
-               out2fmt("%s: %s\n", name, errmsg(e, E_EXEC));
-       entry->cmdtype = CMDUNKNOWN;
-       return;
+       return i;
+}
 
-success:
-       cmdp->rehash = 0;
-       entry->cmdtype = cmdp->cmdtype;
-       entry->u = cmdp->param;
+static int
+evalfun(struct funcnode *func, int argc, char **argv, int flags)
+{
+       volatile struct shparam saveparam;
+       struct localvar *volatile savelocalvars;
+       struct jmploc *volatile savehandler;
+       struct jmploc jmploc;
+       int e;
+
+       saveparam = shellparam;
+       savelocalvars = localvars;
+       if ((e = setjmp(jmploc.loc))) {
+               goto funcdone;
+       }
+       INTOFF;
+       savehandler = handler;
+       handler = &jmploc;
+       localvars = NULL;
+       shellparam.malloc = 0;
+       func->count++;
+       funcnest++;
+       INTON;
+       shellparam.nparam = argc - 1;
+       shellparam.p = argv + 1;
+#ifdef CONFIG_ASH_GETOPTS
+       shellparam.optind = 1;
+       shellparam.optoff = -1;
+#endif
+       evaltree(&func->n, flags & EV_TESTED);
+funcdone:
+       INTOFF;
+       funcnest--;
+       freefunc(func);
+       poplocalvars();
+       localvars = savelocalvars;
+       freeparam(&shellparam);
+       shellparam = saveparam;
+       handler = savehandler;
+       INTON;
+       evalskip &= ~SKIPFUNC;
+       return e;
 }
 
 
+static inline int
+goodname(const char *p)
+{
+       return !*endofname(p);
+}
 
 /*
- * Search the table of builtin commands.
+ * Search for a command.  This is called before we fork so that the
+ * location of the command will be available in the parent as well as
+ * the child.  The check for "goodname" is an overly conservative
+ * check that the name will not be subject to expansion.
  */
 
-static int
-bstrcmp(const void *name, const void *b)
+static void
+prehash(union node *n)
 {
-       return strcmp((const char *)name, (*(const char *const *) b)+1);
+       struct cmdentry entry;
+
+       if (n->type == NCMD && n->ncmd.args)
+               if (goodname(n->ncmd.args->narg.text))
+                       find_command(n->ncmd.args->narg.text, &entry, 0,
+                                    pathval());
 }
 
-static struct builtincmd *
-find_builtin(const char *name)
-{
-       struct builtincmd *bp;
 
-       bp = bsearch(name, builtincmds, NUMBUILTINS, sizeof(struct builtincmd),
-               bstrcmp
-       );
-       return bp;
-}
 
+/*
+ * Builtin commands.  Builtin commands whose functions are closely
+ * tied to evaluation are implemented here.
+ */
 
 /*
- * Called when a cd is done.  Marks all commands so the next time they
- * are executed they will be rehashed.
+ * No command given.
  */
 
-static inline void
-hashcd(void)
+static int
+bltincmd(int argc, char **argv)
 {
-       struct tblentry **pp;
-       struct tblentry *cmdp;
-
-       for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
-               for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
-                       if (cmdp->cmdtype == CMDNORMAL
-                        || (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0))
-                               cmdp->rehash = 1;
-               }
-       }
+       /*
+        * Preserve exitstatus of a previous possible redirection
+        * as POSIX mandates
+        */
+       return back_exitstatus;
 }
 
 
-
 /*
- * Called before PATH is changed.  The argument is the new value of PATH;
- * pathval() still returns the old value at this point.  Called with
- * interrupts off.
+ * Handle break and continue commands.  Break, continue, and return are
+ * all handled by setting the evalskip flag.  The evaluation routines
+ * above all check this flag, and if it is set they start skipping
+ * commands rather than executing them.  The variable skipcount is
+ * the number of loops to break/continue, or the number of function
+ * levels to return.  (The latter is always 1.)  It should probably
+ * be an error to break out of more loops than exist, but it isn't
+ * in the standard shell so we don't make it one here.
  */
 
-static void
-changepath(const char *newval)
+static int
+breakcmd(int argc, char **argv)
 {
-       int firstchange;
-       int bltin;
+       int n = argc > 1 ? number(argv[1]) : 1;
 
-       firstchange = path_change(newval, &bltin);
-       if (builtinloc < 0 && bltin >= 0)
-               builtinloc = bltin;             /* zap builtins */
-       clearcmdentry(firstchange);
-       builtinloc = bltin;
+       if (n <= 0)
+               sh_error(illnum, argv[1]);
+       if (n > loopnest)
+               n = loopnest;
+       if (n > 0) {
+               evalskip = (**argv == 'c')? SKIPCONT : SKIPBREAK;
+               skipcount = n;
+       }
+       return 0;
 }
 
 
 /*
- * Clear out command entries.  The argument specifies the first entry in
- * PATH which has changed.
+ * The return command.
  */
 
-static void
-clearcmdentry(int firstchange)
+static int
+returncmd(int argc, char **argv)
 {
-       struct tblentry **tblp;
-       struct tblentry **pp;
-       struct tblentry *cmdp;
-
-       INTOFF;
-       for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
-               pp = tblp;
-               while ((cmdp = *pp) != NULL) {
-                       if ((cmdp->cmdtype == CMDNORMAL &&
-                            cmdp->param.index >= firstchange)
-                        || (cmdp->cmdtype == CMDBUILTIN &&
-                            builtinloc >= firstchange)) {
-                               *pp = cmdp->next;
-                               ckfree(cmdp);
-                       } else {
-                               pp = &cmdp->next;
-                       }
-               }
-       }
-       INTON;
+       /*
+        * If called outside a function, do what ksh does;
+        * skip the rest of the file.
+        */
+       evalskip = funcnest ? SKIPFUNC : SKIPFILE;
+       return argv[1] ? number(argv[1]) : exitstatus;
 }
 
 
-/*
- * Delete all functions.
- */
-
-static void
-deletefuncs(void)
+static int
+falsecmd(int argc, char **argv)
 {
-       struct tblentry **tblp;
-       struct tblentry **pp;
-       struct tblentry *cmdp;
-
-       INTOFF;
-       for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
-               pp = tblp;
-               while ((cmdp = *pp) != NULL) {
-                       if (cmdp->cmdtype == CMDFUNCTION) {
-                               *pp = cmdp->next;
-                               freefunc(cmdp->param.func);
-                               ckfree(cmdp);
-                       } else {
-                               pp = &cmdp->next;
-                       }
-               }
-       }
-       INTON;
+       return 1;
 }
 
 
+static int
+truecmd(int argc, char **argv)
+{
+       return 0;
+}
 
-/*
- * Locate a command in the command hash table.  If "add" is nonzero,
- * add the command to the table if it is not already present.  The
- * variable "lastcmdentry" is set to point to the address of the link
- * pointing to the entry, so that delete_cmd_entry can delete the
- * entry.
- */
-
-static struct tblentry **lastcmdentry;
 
-static struct tblentry *
-cmdlookup(const char *name, int add)
+static int
+execcmd(int argc, char **argv)
 {
-       int hashval;
-       const char *p;
-       struct tblentry *cmdp;
-       struct tblentry **pp;
-
-       p = name;
-       hashval = *p << 4;
-       while (*p)
-               hashval += *p++;
-       hashval &= 0x7FFF;
-       pp = &cmdtable[hashval % CMDTABLESIZE];
-       for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
-               if (equal(cmdp->cmdname, name))
-                       break;
-               pp = &cmdp->next;
-       }
-       if (add && cmdp == NULL) {
-               INTOFF;
-               cmdp = *pp = xmalloc(sizeof (struct tblentry) - ARB
-                                       + strlen(name) + 1);
-               cmdp->next = NULL;
-               cmdp->cmdtype = CMDUNKNOWN;
-               cmdp->rehash = 0;
-               strcpy(cmdp->cmdname, name);
-               INTON;
+       if (argc > 1) {
+               iflag = 0;              /* exit on error */
+               mflag = 0;
+               optschanged();
+               shellexec(argv + 1, pathval(), 0);
        }
-       lastcmdentry = pp;
-       return cmdp;
+       return 0;
 }
 
+
+/*      exec.c    */
+
 /*
- * Delete the command entry returned on the last lookup.
+ * When commands are first encountered, they are entered in a hash table.
+ * This ensures that a full path search will not have to be done for them
+ * on each invocation.
+ *
+ * We should investigate converting to a linear search, even though that
+ * would make the command name "hash" a misnomer.
  */
 
-static void
-delete_cmd_entry()
-{
-       struct tblentry *cmdp;
+#define CMDTABLESIZE 31         /* should be prime */
+#define ARB 1                   /* actual size determined at run time */
 
-       INTOFF;
-       cmdp = *lastcmdentry;
-       *lastcmdentry = cmdp->next;
-       ckfree(cmdp);
-       INTON;
-}
 
 
+struct tblentry {
+       struct tblentry *next;  /* next entry in hash chain */
+       union param param;      /* definition of builtin function */
+       short cmdtype;          /* index identifying command */
+       char rehash;            /* if set, cd done since entry created */
+       char cmdname[ARB];      /* name of command */
+};
 
 
+static struct tblentry *cmdtable[CMDTABLESIZE];
+static int builtinloc = -1;             /* index in path of %builtin, or -1 */
 
-static const unsigned char nodesize[26] = {
-      ALIGN(sizeof (struct nbinary)),
-      ALIGN(sizeof (struct ncmd)),
-      ALIGN(sizeof (struct npipe)),
-      ALIGN(sizeof (struct nredir)),
-      ALIGN(sizeof (struct nredir)),
-      ALIGN(sizeof (struct nredir)),
-      ALIGN(sizeof (struct nbinary)),
-      ALIGN(sizeof (struct nbinary)),
-      ALIGN(sizeof (struct nif)),
-      ALIGN(sizeof (struct nbinary)),
-      ALIGN(sizeof (struct nbinary)),
-      ALIGN(sizeof (struct nfor)),
-      ALIGN(sizeof (struct ncase)),
-      ALIGN(sizeof (struct nclist)),
-      ALIGN(sizeof (struct narg)),
-      ALIGN(sizeof (struct narg)),
-      ALIGN(sizeof (struct nfile)),
-      ALIGN(sizeof (struct nfile)),
-      ALIGN(sizeof (struct nfile)),
-      ALIGN(sizeof (struct nfile)),
-      ALIGN(sizeof (struct nfile)),
-      ALIGN(sizeof (struct ndup)),
-      ALIGN(sizeof (struct ndup)),
-      ALIGN(sizeof (struct nhere)),
-      ALIGN(sizeof (struct nhere)),
-      ALIGN(sizeof (struct nnot)),
-};
 
+static void tryexec(char *, char **, char **);
+static void clearcmdentry(int);
+static struct tblentry *cmdlookup(const char *, int);
+static void delete_cmd_entry(void);
 
 
 /*
- * Delete a function if it exists.
+ * Exec a program.  Never returns.  If you change this routine, you may
+ * have to change the find_command routine as well.
  */
 
 static void
-unsetfunc(char *name)
+shellexec(char **argv, const char *path, int idx)
 {
-       struct tblentry *cmdp;
+       char *cmdname;
+       int e;
+       char **envp;
+       int exerrno;
 
-       if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->cmdtype == CMDFUNCTION) {
-               freefunc(cmdp->param.func);
-               delete_cmd_entry();
+       clearredir(1);
+       envp = environment();
+       if (strchr(argv[0], '/') != NULL
+#ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
+               || find_applet_by_name(argv[0])
+#endif
+                                               ) {
+               tryexec(argv[0], argv, envp);
+               e = errno;
+       } else {
+               e = ENOENT;
+               while ((cmdname = padvance(&path, argv[0])) != NULL) {
+                       if (--idx < 0 && pathopt == NULL) {
+                               tryexec(cmdname, argv, envp);
+                               if (errno != ENOENT && errno != ENOTDIR)
+                                       e = errno;
+                       }
+                       stunalloc(cmdname);
+               }
        }
-}
-
-
-/*
- * Locate and print what a word is...
- */
-
-static int
-typecmd(int argc, char **argv)
-{
-       int i;
-       int err = 0;
-       char *argv_a[2];
-
-       argv_a[1] = 0;
 
-       for (i = 1; i < argc; i++) {
-               argv_a[0] = argv[i];
-               argptr = argv_a;
-               optptr = "v";
-               err |= hashcmd(argc, argv);
+       /* Map to POSIX errors */
+       switch (e) {
+       case EACCES:
+               exerrno = 126;
+               break;
+       case ENOENT:
+               exerrno = 127;
+               break;
+       default:
+               exerrno = 2;
+               break;
        }
-       return err;
+       exitstatus = exerrno;
+       TRACE(("shellexec failed for %s, errno %d, suppressint %d\n",
+               argv[0], e, suppressint ));
+       exerror(EXEXEC, "%s: %s", argv[0], errmsg(e, E_EXEC));
+       /* NOTREACHED */
 }
 
-#ifdef CONFIG_ASH_CMDCMD
-static int
-commandcmd(int argc, char **argv)
+
+static void
+tryexec(char *cmd, char **argv, char **envp)
 {
-       int c;
-       int default_path = 0;
-       int verify_only = 0;
-       int verbose_verify_only = 0;
+       int repeated = 0;
+#ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
+       if(find_applet_by_name(cmd) != NULL) {
+               /* re-exec ourselves with the new arguments */
+               execve(CONFIG_BUSYBOX_EXEC_PATH,argv,envp);
+               /* If they called chroot or otherwise made the binary no longer
+                * executable, fall through */
+       }
+#endif
 
-       while ((c = nextopt("pvV")) != '\0')
-               switch (c) {
-               case 'p':
-                       default_path = 1;
-                       break;
-               case 'v':
-                       verify_only = 1;
-                       break;
-               case 'V':
-                       verbose_verify_only = 1;
-                       break;
-               }
+repeat:
+#ifdef SYSV
+       do {
+               execve(cmd, argv, envp);
+       } while (errno == EINTR);
+#else
+       execve(cmd, argv, envp);
+#endif
+       if (repeated++) {
+               ckfree(argv);
+       } else if (errno == ENOEXEC) {
+               char **ap;
+               char **new;
 
-       if (default_path + verify_only + verbose_verify_only > 1 ||
-           !*argptr) {
-                       out2str(
-                               "command [-p] command [arg ...]\n"
-                               "command {-v|-V} command\n");
-                       return EX_USAGE;
+               for (ap = argv; *ap; ap++)
+                       ;
+               ap = new = ckmalloc((ap - argv + 2) * sizeof(char *));
+               ap[1] = cmd;
+               *ap = cmd = (char *)DEFAULT_SHELL;
+               ap += 2;
+               argv++;
+               while ((*ap++ = *argv++))
+                       ;
+               argv = new;
+               goto repeat;
        }
+}
 
-       if (verify_only || verbose_verify_only) {
-               char *argv_a[2];
 
-               argv_a[1] = 0;
-               argv_a[0] = *argptr;
-               argptr = argv_a;
-               optptr = verbose_verify_only ? "v" : "V"; /* reverse special */
-               return hashcmd(argc, argv);
-       }
 
-       return 0;
-}
-#endif
+/*
+ * Do a path search.  The variable path (passed by reference) should be
+ * set to the start of the path before the first call; padvance will update
+ * this value as it proceeds.  Successive calls to padvance will return
+ * the possible path expansions in sequence.  If an option (indicated by
+ * a percent sign) appears in the path entry then the global variable
+ * pathopt will be set to point to it; otherwise pathopt will be set to
+ * NULL.
+ */
 
-static int
-path_change(const char *newval, int *bltin)
+static char *
+padvance(const char **path, const char *name)
 {
-       const char *old, *new;
-       int idx;
-       int firstchange;
+       const char *p;
+       char *q;
+       const char *start;
+       size_t len;
 
-       old = pathval();
-       new = newval;
-       firstchange = 9999;     /* assume no change */
-       idx = 0;
-       *bltin = -1;
-       for (;;) {
-               if (*old != *new) {
-                       firstchange = idx;
-                       if ((*old == '\0' && *new == ':')
-                        || (*old == ':' && *new == '\0'))
-                               firstchange++;
-                       old = new;      /* ignore subsequent differences */
-               }
-               if (*new == '\0')
-                       break;
-               if (*new == '%' && *bltin < 0 && prefix("builtin", new + 1))
-                       *bltin = idx;
-               if (*new == ':') {
-                       idx++;
-               }
-               new++, old++;
+       if (*path == NULL)
+               return NULL;
+       start = *path;
+       for (p = start ; *p && *p != ':' && *p != '%' ; p++);
+       len = p - start + strlen(name) + 2;     /* "2" is for '/' and '\0' */
+       while (stackblocksize() < len)
+               growstackblock();
+       q = stackblock();
+       if (p != start) {
+               memcpy(q, start, p - start);
+               q += p - start;
+               *q++ = '/';
        }
-       if (builtinloc >= 0 && *bltin < 0)
-               firstchange = 0;
-       /* Ensure that getenv("PATH") stays current */
-       setenv("PATH", newval, 1);
-       return firstchange;
+       strcpy(q, name);
+       pathopt = NULL;
+       if (*p == '%') {
+               pathopt = ++p;
+               while (*p && *p != ':')  p++;
+       }
+       if (*p == ':')
+               *path = p + 1;
+       else
+               *path = NULL;
+       return stalloc(len);
 }
-/*
- * Routines to expand arguments to commands.  We have to deal with
- * backquotes, shell variables, and file metacharacters.
- */
-/*
- * _rmescape() flags
- */
-#define RMESCAPE_ALLOC  0x1     /* Allocate a new string */
-#define RMESCAPE_GLOB   0x2     /* Add backslashes for glob */
-
-/*
- * Structure specifying which parts of the string should be searched
- * for IFS characters.
- */
-
-struct ifsregion {
-       struct ifsregion *next; /* next region in list */
-       int begoff;             /* offset of start of region */
-       int endoff;             /* offset of end of region */
-       int nulonly;            /* search for nul bytes only */
-};
 
 
-static char *expdest;                   /* output of current string */
-static struct nodelist *argbackq;      /* list of back quote expressions */
-static struct ifsregion ifsfirst;      /* first struct in list of ifs regions */
-static struct ifsregion *ifslastp;     /* last struct in list */
-static struct arglist exparg;          /* holds expanded arg list */
-
-static void argstr (char *, int);
-static char *exptilde (char *, int);
-static void expbackq (union node *, int, int);
-static int subevalvar (char *, char *, int, int, int, int, int);
-static int varisset (char *, int);
-static void strtodest (const char *, int, int);
-static inline void varvalue (char *, int, int);
-static void recordregion (int, int, int);
-static void removerecordregions (int);
-static void ifsbreakup (char *, struct arglist *);
-static void ifsfree (void);
-static void expandmeta (struct strlist *, int);
-#if defined(__GLIBC__) && __GLIBC__ >= 2 && !defined(FNMATCH_BROKEN)
-#define preglob(p) _rmescapes((p), RMESCAPE_ALLOC | RMESCAPE_GLOB)
-#if !defined(GLOB_BROKEN)
-static inline void addglob (const glob_t *);
-#endif
-#endif
-#if !(defined(__GLIBC__) && __GLIBC__ >= 2 && !defined(FNMATCH_BROKEN) && !defined(GLOB_BROKEN))
-static void expmeta (char *, char *);
-#endif
-#if !(defined(__GLIBC__) && __GLIBC__ >= 2 && !defined(FNMATCH_BROKEN) && !defined(GLOB_BROKEN))
-static struct strlist *expsort (struct strlist *);
-static struct strlist *msort (struct strlist *, int);
-#endif
-static int patmatch (char *, char *, int);
-#if defined(__GLIBC__) && __GLIBC__ >= 2 && !defined(FNMATCH_BROKEN)
-static int patmatch2 (char *, char *, int);
-#else
-static int pmatch (char *, char *, int);
-#define patmatch2 patmatch
-#endif
-static char *cvtnum (int, char *);
-
-/*
- * Expand shell variables and backquotes inside a here document.
- */
+/*** Command hashing code ***/
 
-/* arg: the document, fd: where to write the expanded version */
-static inline void
-expandhere(union node *arg, int fd)
+static void
+printentry(struct tblentry *cmdp)
 {
-       herefd = fd;
-       expandarg(arg, (struct arglist *)NULL, 0);
-       xwrite(fd, stackblock(), expdest - stackblock());
-}
+       int idx;
+       const char *path;
+       char *name;
 
+       idx = cmdp->param.index;
+       path = pathval();
+       do {
+               name = padvance(&path, cmdp->cmdname);
+               stunalloc(name);
+       } while (--idx >= 0);
+       out1fmt("%s%s\n", name, (cmdp->rehash ? "*" : nullstr));
+}
 
-/*
- * Perform variable substitution and command substitution on an argument,
- * placing the resulting list of arguments in arglist.  If EXP_FULL is true,
- * perform splitting and file name expansion.  When arglist is NULL, perform
- * here document expansion.
- */
 
-static void
-expandarg(union node *arg, struct arglist *arglist, int flag)
+static int
+hashcmd(int argc, char **argv)
 {
-       struct strlist *sp;
-       char *p;
+       struct tblentry **pp;
+       struct tblentry *cmdp;
+       int c;
+       struct cmdentry entry;
+       char *name;
 
-       argbackq = arg->narg.backquote;
-       STARTSTACKSTR(expdest);
-       ifsfirst.next = NULL;
-       ifslastp = NULL;
-       argstr(arg->narg.text, flag);
-       if (arglist == NULL) {
-               return;                 /* here document expanded */
+       while ((c = nextopt("r")) != '\0') {
+               clearcmdentry(0);
+               return 0;
        }
-       STPUTC('\0', expdest);
-       p = grabstackstr(expdest);
-       exparg.lastp = &exparg.list;
-       /*
-        * TODO - EXP_REDIR
-        */
-       if (flag & EXP_FULL) {
-               ifsbreakup(p, &exparg);
-               *exparg.lastp = NULL;
-               exparg.lastp = &exparg.list;
-               expandmeta(exparg.list, flag);
-       } else {
-               if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */
-                       rmescapes(p);
-               sp = (struct strlist *)stalloc(sizeof (struct strlist));
-               sp->text = p;
-               *exparg.lastp = sp;
-               exparg.lastp = &sp->next;
+       if (*argptr == NULL) {
+               for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
+                       for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
+                               if (cmdp->cmdtype == CMDNORMAL)
+                                       printentry(cmdp);
+                       }
+               }
+               return 0;
        }
-       ifsfree();
-       *exparg.lastp = NULL;
-       if (exparg.list) {
-               *arglist->lastp = exparg.list;
-               arglist->lastp = exparg.lastp;
+       c = 0;
+       while ((name = *argptr) != NULL) {
+               if ((cmdp = cmdlookup(name, 0)) != NULL
+                && (cmdp->cmdtype == CMDNORMAL
+                    || (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0)))
+                       delete_cmd_entry();
+               find_command(name, &entry, DO_ERR, pathval());
+               if (entry.cmdtype == CMDUNKNOWN)
+                       c = 1;
+               argptr++;
        }
+       return c;
 }
 
 
 /*
- * Expand a variable, and return a pointer to the next character in the
- * input string.
+ * Resolve a command name.  If you change this routine, you may have to
+ * change the shellexec routine as well.
  */
 
-static inline char * evalvar(char *p, int flag)
+static void
+find_command(char *name, struct cmdentry *entry, int act, const char *path)
 {
-       int subtype;
-       int varflags;
-       char *var;
-       const char *val;
-       int patloc;
-       int c;
-       int set;
-       int special;
-       int startloc;
-       int varlen;
-       int easy;
-       int quotes = flag & (EXP_FULL | EXP_CASE);
+       struct tblentry *cmdp;
+       int idx;
+       int prev;
+       char *fullname;
+       struct stat statb;
+       int e;
+       int updatetbl;
+       struct builtincmd *bcmd;
 
-       varflags = *p++;
-       subtype = varflags & VSTYPE;
-       var = p;
-       special = 0;
-       if (! is_name(*p))
-               special = 1;
-       p = strchr(p, '=') + 1;
-again: /* jump here after setting a variable with ${var=text} */
-       if (special) {
-               set = varisset(var, varflags & VSNUL);
-               val = NULL;
-       } else {
-               val = lookupvar(var);
-               if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) {
-                       val = NULL;
-                       set = 0;
-               } else
-                       set = 1;
-       }
-       varlen = 0;
-       startloc = expdest - stackblock();
-       if (set && subtype != VSPLUS) {
-               /* insert the value of the variable */
-               if (special) {
-                       varvalue(var, varflags & VSQUOTE, flag);
-                       if (subtype == VSLENGTH) {
-                               varlen = expdest - stackblock() - startloc;
-                               STADJUST(-varlen, expdest);
-                       }
-               } else {
-                       if (subtype == VSLENGTH) {
-                               varlen = strlen(val);
-                       } else {
-                               strtodest(
-                                       val,
-                                       varflags & VSQUOTE ?
-                                               DQSYNTAX : BASESYNTAX,
-                                       quotes
-                               );
+       /* If name contains a slash, don't use PATH or hash table */
+       if (strchr(name, '/') != NULL) {
+               entry->u.index = -1;
+               if (act & DO_ABS) {
+                       while (stat(name, &statb) < 0) {
+#ifdef SYSV
+                               if (errno == EINTR)
+                                       continue;
+#endif
+                               entry->cmdtype = CMDUNKNOWN;
+                               return;
                        }
                }
+               entry->cmdtype = CMDNORMAL;
+               return;
        }
 
-       if (subtype == VSPLUS)
-               set = ! set;
-
-       easy = ((varflags & VSQUOTE) == 0 ||
-               (*var == '@' && shellparam.nparam != 1));
+#ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
+       if (find_applet_by_name(name)) {
+               entry->cmdtype = CMDNORMAL;
+               entry->u.index = -1;
+               return;
+       }
+#endif
 
+       updatetbl = (path == pathval());
+       if (!updatetbl) {
+               act |= DO_ALTPATH;
+               if (strstr(path, "%builtin") != NULL)
+                       act |= DO_ALTBLTIN;
+       }
 
-       switch (subtype) {
-       case VSLENGTH:
-               expdest = cvtnum(varlen, expdest);
-               goto record;
+       /* If name is in the table, check answer will be ok */
+       if ((cmdp = cmdlookup(name, 0)) != NULL) {
+               int bit;
 
-       case VSNORMAL:
-               if (!easy)
+               switch (cmdp->cmdtype) {
+               default:
+#if DEBUG
+                       abort();
+#endif
+               case CMDNORMAL:
+                       bit = DO_ALTPATH;
                        break;
-record:
-               recordregion(startloc, expdest - stackblock(),
-                            varflags & VSQUOTE);
-               break;
-
-       case VSPLUS:
-       case VSMINUS:
-               if (!set) {
-                       argstr(p, flag);
+               case CMDFUNCTION:
+                       bit = DO_NOFUNC;
                        break;
-               }
-               if (easy)
-                       goto record;
-               break;
-
-       case VSTRIMLEFT:
-       case VSTRIMLEFTMAX:
-       case VSTRIMRIGHT:
-       case VSTRIMRIGHTMAX:
-               if (!set)
+               case CMDBUILTIN:
+                       bit = DO_ALTBLTIN;
                        break;
-               /*
-                * Terminate the string and start recording the pattern
-                * right after it
-                */
-               STPUTC('\0', expdest);
-               patloc = expdest - stackblock();
-               if (subevalvar(p, NULL, patloc, subtype,
-                              startloc, varflags, quotes) == 0) {
-                       int amount = (expdest - stackblock() - patloc) + 1;
-                       STADJUST(-amount, expdest);
                }
-               /* Remove any recorded regions beyond start of variable */
-               removerecordregions(startloc);
-               goto record;
+               if (act & bit) {
+                       updatetbl = 0;
+                       cmdp = NULL;
+               } else if (cmdp->rehash == 0)
+                       /* if not invalidated by cd, we're done */
+                       goto success;
+       }
 
-       case VSASSIGN:
-       case VSQUESTION:
-               if (!set) {
-                       if (subevalvar(p, var, 0, subtype, startloc,
-                                      varflags, quotes)) {
-                               varflags &= ~VSNUL;
-                               /*
-                                * Remove any recorded regions beyond
-                                * start of variable
-                                */
-                               removerecordregions(startloc);
-                               goto again;
-                       }
-                       break;
-               }
-               if (easy)
-                       goto record;
-               break;
+       /* If %builtin not in path, check for builtin next */
+       bcmd = find_builtin(name);
+       if (bcmd && (IS_BUILTIN_REGULAR(bcmd) || (
+               act & DO_ALTPATH ? !(act & DO_ALTBLTIN) : builtinloc <= 0
+       )))
+               goto builtin_success;
 
-#ifdef DEBUG
-       default:
-               abort();
-#endif
+       /* We have to search path. */
+       prev = -1;              /* where to start */
+       if (cmdp && cmdp->rehash) {     /* doing a rehash */
+               if (cmdp->cmdtype == CMDBUILTIN)
+                       prev = builtinloc;
+               else
+                       prev = cmdp->param.index;
        }
 
-       if (subtype != VSNORMAL) {      /* skip to end of alternative */
-               int nesting = 1;
-               for (;;) {
-                       if ((c = *p++) == CTLESC)
-                               p++;
-                       else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
-                               if (set)
-                                       argbackq = argbackq->next;
-                       } else if (c == CTLVAR) {
-                               if ((*p++ & VSTYPE) != VSNORMAL)
-                                       nesting++;
-                       } else if (c == CTLENDVAR) {
-                               if (--nesting == 0)
-                                       break;
+       e = ENOENT;
+       idx = -1;
+loop:
+       while ((fullname = padvance(&path, name)) != NULL) {
+               stunalloc(fullname);
+               idx++;
+               if (pathopt) {
+                       if (prefix(pathopt, "builtin")) {
+                               if (bcmd)
+                                       goto builtin_success;
+                               continue;
+                       } else if (!(act & DO_NOFUNC) &&
+                                  prefix(pathopt, "func")) {
+                               /* handled below */
+                       } else {
+                               /* ignore unimplemented options */
+                               continue;
                        }
                }
+               /* if rehash, don't redo absolute path names */
+               if (fullname[0] == '/' && idx <= prev) {
+                       if (idx < prev)
+                               continue;
+                       TRACE(("searchexec \"%s\": no change\n", name));
+                       goto success;
+               }
+               while (stat(fullname, &statb) < 0) {
+#ifdef SYSV
+                       if (errno == EINTR)
+                               continue;
+#endif
+                       if (errno != ENOENT && errno != ENOTDIR)
+                               e = errno;
+                       goto loop;
+               }
+               e = EACCES;     /* if we fail, this will be the error */
+               if (!S_ISREG(statb.st_mode))
+                       continue;
+               if (pathopt) {          /* this is a %func directory */
+                       stalloc(strlen(fullname) + 1);
+                       readcmdfile(fullname);
+                       if ((cmdp = cmdlookup(name, 0)) == NULL ||
+                           cmdp->cmdtype != CMDFUNCTION)
+                               sh_error("%s not defined in %s", name, fullname);
+                       stunalloc(fullname);
+                       goto success;
+               }
+               TRACE(("searchexec \"%s\" returns \"%s\"\n", name, fullname));
+               if (!updatetbl) {
+                       entry->cmdtype = CMDNORMAL;
+                       entry->u.index = idx;
+                       return;
+               }
+               INTOFF;
+               cmdp = cmdlookup(name, 1);
+               cmdp->cmdtype = CMDNORMAL;
+               cmdp->param.index = idx;
+               INTON;
+               goto success;
        }
-       return p;
+
+       /* We failed.  If there was an entry for this command, delete it */
+       if (cmdp && updatetbl)
+               delete_cmd_entry();
+       if (act & DO_ERR)
+               sh_warnx("%s: %s", name, errmsg(e, E_EXEC));
+       entry->cmdtype = CMDUNKNOWN;
+       return;
+
+builtin_success:
+       if (!updatetbl) {
+               entry->cmdtype = CMDBUILTIN;
+               entry->u.cmd = bcmd;
+               return;
+       }
+       INTOFF;
+       cmdp = cmdlookup(name, 1);
+       cmdp->cmdtype = CMDBUILTIN;
+       cmdp->param.cmd = bcmd;
+       INTON;
+success:
+       cmdp->rehash = 0;
+       entry->cmdtype = cmdp->cmdtype;
+       entry->u = cmdp->param;
 }
 
 
 /*
- * Perform variable and command substitution.  If EXP_FULL is set, output CTLESC
- * characters to allow for further processing.  Otherwise treat
- * $@ like $* since no splitting will be performed.
+ * Wrapper around strcmp for qsort/bsearch/...
+ */
+static int pstrcmp(const void *a, const void *b)
+{
+       return strcmp((const char *) a, (*(const char *const *) b) + 1);
+}
+
+/*
+ * Search the table of builtin commands.
  */
 
-static void
-argstr(char *p, int flag)
+static struct builtincmd *
+find_builtin(const char *name)
 {
-       char c;
-       int quotes = flag & (EXP_FULL | EXP_CASE);      /* do CTLESC */
-       int firsteq = 1;
+       struct builtincmd *bp;
 
-       if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE)))
-               p = exptilde(p, flag);
-       for (;;) {
-               switch (c = *p++) {
-               case '\0':
-               case CTLENDVAR: /* ??? */
-                       return;
-               case CTLQUOTEMARK:
-                       /* "$@" syntax adherence hack */
-                       if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=')
-                               break;
-                       if ((flag & EXP_FULL) != 0)
-                               STPUTC(c, expdest);
-                       break;
-               case CTLESC:
-                       if (quotes)
-                               STPUTC(c, expdest);
-                       c = *p++;
-                       STPUTC(c, expdest);
-                       break;
-               case CTLVAR:
-                       p = evalvar(p, flag);
-                       break;
-               case CTLBACKQ:
-               case CTLBACKQ|CTLQUOTE:
-                       expbackq(argbackq->n, c & CTLQUOTE, flag);
-                       argbackq = argbackq->next;
-                       break;
-#ifdef CONFIG_ASH_MATH_SUPPORT
-               case CTLENDARI:
-                       expari(flag);
-                       break;
-#endif
-               case ':':
-               case '=':
-                       /*
-                        * sort of a hack - expand tildes in variable
-                        * assignments (after the first '=' and after ':'s).
-                        */
-                       STPUTC(c, expdest);
-                       if (flag & EXP_VARTILDE && *p == '~') {
-                               if (c == '=') {
-                                       if (firsteq)
-                                               firsteq = 0;
-                                       else
-                                               break;
-                               }
-                               p = exptilde(p, flag);
-                       }
-                       break;
-               default:
-                       STPUTC(c, expdest);
-               }
-       }
-       return;
+       bp = bsearch(
+               name, builtincmd, NUMBUILTINS, sizeof(struct builtincmd),
+               pstrcmp
+       );
+       return bp;
 }
 
-static char *
-exptilde(char *p, int flag)
+
+
+/*
+ * Called when a cd is done.  Marks all commands so the next time they
+ * are executed they will be rehashed.
+ */
+
+static void
+hashcd(void)
 {
-       char c, *startp = p;
-       struct passwd *pw;
-       const char *home;
-       int quotes = flag & (EXP_FULL | EXP_CASE);
+       struct tblentry **pp;
+       struct tblentry *cmdp;
 
-       while ((c = *p) != '\0') {
-               switch(c) {
-               case CTLESC:
-                       return (startp);
-               case CTLQUOTEMARK:
-                       return (startp);
-               case ':':
-                       if (flag & EXP_VARTILDE)
-                               goto done;
-                       break;
-               case '/':
-                       goto done;
+       for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
+               for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
+                       if (cmdp->cmdtype == CMDNORMAL || (
+                               cmdp->cmdtype == CMDBUILTIN &&
+                               !(IS_BUILTIN_REGULAR(cmdp->param.cmd)) &&
+                               builtinloc > 0
+                       ))
+                               cmdp->rehash = 1;
                }
-               p++;
-       }
-done:
-       *p = '\0';
-       if (*(startp+1) == '\0') {
-               if ((home = lookupvar("HOME")) == NULL)
-                       goto lose;
-       } else {
-               if ((pw = getpwnam(startp+1)) == NULL)
-                       goto lose;
-               home = pw->pw_dir;
        }
-       if (*home == '\0')
-               goto lose;
-       *p = c;
-       strtodest(home, SQSYNTAX, quotes);
-       return (p);
-lose:
-       *p = c;
-       return (startp);
 }
 
 
+
+/*
+ * Fix command hash table when PATH changed.
+ * Called before PATH is changed.  The argument is the new value of PATH;
+ * pathval() still returns the old value at this point.
+ * Called with interrupts off.
+ */
+
 static void
-removerecordregions(int endoff)
+changepath(const char *newval)
 {
-       if (ifslastp == NULL)
-               return;
+       const char *old, *new;
+       int idx;
+       int firstchange;
+       int idx_bltin;
 
-       if (ifsfirst.endoff > endoff) {
-               while (ifsfirst.next != NULL) {
-                       struct ifsregion *ifsp;
-                       INTOFF;
-                       ifsp = ifsfirst.next->next;
-                       ckfree(ifsfirst.next);
-                       ifsfirst.next = ifsp;
-                       INTON;
+       old = pathval();
+       new = newval;
+       firstchange = 9999;     /* assume no change */
+       idx = 0;
+       idx_bltin = -1;
+       for (;;) {
+               if (*old != *new) {
+                       firstchange = idx;
+                       if ((*old == '\0' && *new == ':')
+                        || (*old == ':' && *new == '\0'))
+                               firstchange++;
+                       old = new;      /* ignore subsequent differences */
                }
-               if (ifsfirst.begoff > endoff)
-                       ifslastp = NULL;
-               else {
-                       ifslastp = &ifsfirst;
-                       ifsfirst.endoff = endoff;
+               if (*new == '\0')
+                       break;
+               if (*new == '%' && idx_bltin < 0 && prefix(new + 1, "builtin"))
+                       idx_bltin = idx;
+               if (*new == ':') {
+                       idx++;
                }
-               return;
-       }
-
-       ifslastp = &ifsfirst;
-       while (ifslastp->next && ifslastp->next->begoff < endoff)
-               ifslastp=ifslastp->next;
-       while (ifslastp->next != NULL) {
-               struct ifsregion *ifsp;
-               INTOFF;
-               ifsp = ifslastp->next->next;
-               ckfree(ifslastp->next);
-               ifslastp->next = ifsp;
-               INTON;
+               new++, old++;
        }
-       if (ifslastp->endoff > endoff)
-               ifslastp->endoff = endoff;
+       if (builtinloc < 0 && idx_bltin >= 0)
+               builtinloc = idx_bltin;             /* zap builtins */
+       if (builtinloc >= 0 && idx_bltin < 0)
+               firstchange = 0;
+       clearcmdentry(firstchange);
+       builtinloc = idx_bltin;
 }
 
 
-#ifdef CONFIG_ASH_MATH_SUPPORT
 /*
- * Expand arithmetic expression.  Backup to start of expression,
- * evaluate, place result in (backed up) result, adjust string position.
+ * Clear out command entries.  The argument specifies the first entry in
+ * PATH which has changed.
  */
+
 static void
-expari(int flag)
+clearcmdentry(int firstchange)
 {
-       char *p, *start;
-       int errcode;
-       int result;
-       int begoff;
-       int quotes = flag & (EXP_FULL | EXP_CASE);
-       int quoted;
-
-       /*      ifsfree(); */
+       struct tblentry **tblp;
+       struct tblentry **pp;
+       struct tblentry *cmdp;
 
-       /*
-        * This routine is slightly over-complicated for
-        * efficiency.  First we make sure there is
-        * enough space for the result, which may be bigger
-        * than the expression if we add exponentation.  Next we
-        * scan backwards looking for the start of arithmetic.  If the
-        * next previous character is a CTLESC character, then we
-        * have to rescan starting from the beginning since CTLESC
-        * characters have to be processed left to right.
-        */
-       CHECKSTRSPACE(10, expdest);
-       USTPUTC('\0', expdest);
-       start = stackblock();
-       p = expdest - 1;
-       while (*p != CTLARI && p >= start)
-               --p;
-       if (*p != CTLARI)
-               error("missing CTLARI (shouldn't happen)");
-       if (p > start && *(p-1) == CTLESC)
-               for (p = start; *p != CTLARI; p++)
-                       if (*p == CTLESC)
-                               p++;
-
-       if (p[1] == '"')
-               quoted=1;
-       else
-               quoted=0;
-       begoff = p - start;
-       removerecordregions(begoff);
-       if (quotes)
-               rmescapes(p+2);
-       result = arith(p+2, &errcode);
-       if (errcode < 0) {
-               if(errcode == -2)
-                       error("divide by zero");
-               else
-                       error("syntax error: \"%s\"\n", p+2);
+       INTOFF;
+       for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
+               pp = tblp;
+               while ((cmdp = *pp) != NULL) {
+                       if ((cmdp->cmdtype == CMDNORMAL &&
+                            cmdp->param.index >= firstchange)
+                        || (cmdp->cmdtype == CMDBUILTIN &&
+                            builtinloc >= firstchange)) {
+                               *pp = cmdp->next;
+                               ckfree(cmdp);
+                       } else {
+                               pp = &cmdp->next;
+                       }
+               }
        }
-       snprintf(p, 12, "%d", result);
+       INTON;
+}
 
-       while (*p++)
-               ;
 
-       if (quoted == 0)
-               recordregion(begoff, p - 1 - start, 0);
-       result = expdest - p + 1;
-       STADJUST(-result, expdest);
-}
-#endif
 
 /*
- * Expand stuff in backwards quotes.
+ * Locate a command in the command hash table.  If "add" is nonzero,
+ * add the command to the table if it is not already present.  The
+ * variable "lastcmdentry" is set to point to the address of the link
+ * pointing to the entry, so that delete_cmd_entry can delete the
+ * entry.
+ *
+ * Interrupts must be off if called with add != 0.
  */
 
-static void
-expbackq(union node *cmd, int quoted, int flag)
-{
-       volatile struct backcmd in;
-       int i;
-       char buf[128];
-       char *p;
-       char *dest = expdest;
-       volatile struct ifsregion saveifs;
-       struct ifsregion *volatile savelastp;
-       struct nodelist *volatile saveargbackq;
-       char lastc;
-       int startloc = dest - stackblock();
-       int syntax = quoted ? DQSYNTAX : BASESYNTAX;
-       volatile int saveherefd;
-       int quotes = flag & (EXP_FULL | EXP_CASE);
-       struct jmploc jmploc;
-       struct jmploc *volatile savehandler;
-       int ex;
+static struct tblentry **lastcmdentry;
 
-#if __GNUC__
-       /* Avoid longjmp clobbering */
-       (void) &dest;
-       (void) &syntax;
-#endif
 
-       in.fd = -1;
-       in.buf = 0;
-       in.jp = 0;
+static struct tblentry *
+cmdlookup(const char *name, int add)
+{
+       unsigned int hashval;
+       const char *p;
+       struct tblentry *cmdp;
+       struct tblentry **pp;
 
-       INTOFF;
-       saveifs = ifsfirst;
-       savelastp = ifslastp;
-       saveargbackq = argbackq;
-       saveherefd = herefd;
-       herefd = -1;
-       if ((ex = setjmp(jmploc.loc))) {
-               goto err1;
+       p = name;
+       hashval = (unsigned char)*p << 4;
+       while (*p)
+               hashval += (unsigned char)*p++;
+       hashval &= 0x7FFF;
+       pp = &cmdtable[hashval % CMDTABLESIZE];
+       for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
+               if (equal(cmdp->cmdname, name))
+                       break;
+               pp = &cmdp->next;
        }
-       savehandler = handler;
-       handler = &jmploc;
-       INTON;
-       p = grabstackstr(dest);
-       evalbackcmd(cmd, (struct backcmd *) &in);
-       ungrabstackstr(p, dest);
-err1:
-       INTOFF;
-       ifsfirst = saveifs;
-       ifslastp = savelastp;
-       argbackq = saveargbackq;
-       herefd = saveherefd;
-       if (ex) {
-               goto err2;
+       if (add && cmdp == NULL) {
+               cmdp = *pp = ckmalloc(sizeof (struct tblentry) - ARB
+                                       + strlen(name) + 1);
+               cmdp->next = NULL;
+               cmdp->cmdtype = CMDUNKNOWN;
+               strcpy(cmdp->cmdname, name);
        }
+       lastcmdentry = pp;
+       return cmdp;
+}
 
-       p = in.buf;
-       lastc = '\0';
-       for (;;) {
-               if (--in.nleft < 0) {
-                       if (in.fd < 0)
-                               break;
-                       i = safe_read(in.fd, buf, sizeof buf);
-                       TRACE(("expbackq: read returns %d\n", i));
-                       if (i <= 0)
-                               break;
-                       p = buf;
-                       in.nleft = i - 1;
-               }
-               lastc = *p++;
-               if (lastc != '\0') {
-                       if (quotes && SIT(lastc, syntax) == CCTL)
-                               STPUTC(CTLESC, dest);
-                       STPUTC(lastc, dest);
-               }
-       }
+/*
+ * Delete the command entry returned on the last lookup.
+ */
 
-       /* Eat all trailing newlines */
-       for (; dest > stackblock() && dest[-1] == '\n';)
-               STUNPUTC(dest);
+static void
+delete_cmd_entry(void)
+{
+       struct tblentry *cmdp;
 
-err2:
-       if (in.fd >= 0)
-               close(in.fd);
-       if (in.buf)
-               ckfree(in.buf);
-       if (in.jp)
-               exitstatus = waitforjob(in.jp);
-       handler = savehandler;
-       if (ex) {
-               longjmp(handler->loc, 1);
-       }
-       if (quoted == 0)
-               recordregion(startloc, dest - stackblock(), 0);
-       TRACE(("evalbackq: size=%d: \"%.*s\"\n",
-               (dest - stackblock()) - startloc,
-               (dest - stackblock()) - startloc,
-               stackblock() + startloc));
-       expdest = dest;
+       INTOFF;
+       cmdp = *lastcmdentry;
+       *lastcmdentry = cmdp->next;
+       if (cmdp->cmdtype == CMDFUNCTION)
+               freefunc(cmdp->param.func);
+       ckfree(cmdp);
        INTON;
 }
 
-static int
-subevalvar(char *p, char *str, int strloc, int subtype, int startloc, int varflags, int quotes)
-{
-       char *startp;
-       char *loc = NULL;
-       char *q;
-       int c = 0;
-       int saveherefd = herefd;
-       struct nodelist *saveargbackq = argbackq;
-       int amount;
-
-       herefd = -1;
-       argstr(p, subtype != VSASSIGN && subtype != VSQUESTION ? EXP_CASE : 0);
-       STACKSTRNUL(expdest);
-       herefd = saveherefd;
-       argbackq = saveargbackq;
-       startp = stackblock() + startloc;
-       if (str == NULL)
-           str = stackblock() + strloc;
-
-       switch (subtype) {
-       case VSASSIGN:
-               setvar(str, startp, 0);
-               amount = startp - expdest;
-               STADJUST(amount, expdest);
-               varflags &= ~VSNUL;
-               if (c != 0)
-                       *loc = c;
-               return 1;
-
-       case VSQUESTION:
-               if (*p != CTLENDVAR) {
-                       out2fmt(snlfmt, startp);
-                       error((char *)NULL);
-               }
-               error("%.*s: parameter %snot set", p - str - 1,
-                     str, (varflags & VSNUL) ? "null or "
-                                             : nullstr);
-               /* NOTREACHED */
-
-       case VSTRIMLEFT:
-               for (loc = startp; loc < str; loc++) {
-                       c = *loc;
-                       *loc = '\0';
-                       if (patmatch2(str, startp, quotes))
-                               goto recordleft;
-                       *loc = c;
-                       if (quotes && *loc == CTLESC)
-                               loc++;
-               }
-               return 0;
-
-       case VSTRIMLEFTMAX:
-               for (loc = str - 1; loc >= startp;) {
-                       c = *loc;
-                       *loc = '\0';
-                       if (patmatch2(str, startp, quotes))
-                               goto recordleft;
-                       *loc = c;
-                       loc--;
-                       if (quotes && loc > startp && *(loc - 1) == CTLESC) {
-                               for (q = startp; q < loc; q++)
-                                       if (*q == CTLESC)
-                                               q++;
-                               if (q > loc)
-                                       loc--;
-                       }
-               }
-               return 0;
 
-       case VSTRIMRIGHT:
-               for (loc = str - 1; loc >= startp;) {
-                       if (patmatch2(str, loc, quotes))
-                               goto recordright;
-                       loc--;
-                       if (quotes && loc > startp && *(loc - 1) == CTLESC) {
-                               for (q = startp; q < loc; q++)
-                                       if (*q == CTLESC)
-                                               q++;
-                               if (q > loc)
-                                       loc--;
-                       }
-               }
-               return 0;
+/*
+ * Add a new command entry, replacing any existing command entry for
+ * the same name - except special builtins.
+ */
 
-       case VSTRIMRIGHTMAX:
-               for (loc = startp; loc < str - 1; loc++) {
-                       if (patmatch2(str, loc, quotes))
-                               goto recordright;
-                       if (quotes && *loc == CTLESC)
-                               loc++;
-               }
-               return 0;
+static inline void
+addcmdentry(char *name, struct cmdentry *entry)
+{
+       struct tblentry *cmdp;
 
-#ifdef DEBUG
-       default:
-               abort();
-#endif
+       cmdp = cmdlookup(name, 1);
+       if (cmdp->cmdtype == CMDFUNCTION) {
+               freefunc(cmdp->param.func);
        }
-
-recordleft:
-       *loc = c;
-       amount = ((str - 1) - (loc - startp)) - expdest;
-       STADJUST(amount, expdest);
-       while (loc != str - 1)
-               *startp++ = *loc++;
-       return 1;
-
-recordright:
-       amount = loc - expdest;
-       STADJUST(amount, expdest);
-       STPUTC('\0', expdest);
-       STADJUST(-1, expdest);
-       return 1;
+       cmdp->cmdtype = entry->cmdtype;
+       cmdp->param = entry->u;
+       cmdp->rehash = 0;
 }
 
-
 /*
- * Test whether a specialized variable is set.
+ * Make a copy of a parse tree.
  */
 
-static int
-varisset(char *name, int nulok)
+static inline struct funcnode *
+copyfunc(union node *n)
 {
-       if (*name == '!')
-               return backgndpid != -1;
-       else if (*name == '@' || *name == '*') {
-               if (*shellparam.p == NULL)
-                       return 0;
+       struct funcnode *f;
+       size_t blocksize;
 
-               if (nulok) {
-                       char **av;
-
-                       for (av = shellparam.p; *av; av++)
-                               if (**av != '\0')
-                                       return 1;
-                       return 0;
-               }
-       } else if (is_digit(*name)) {
-               char *ap;
-               int num = atoi(name);
+       funcblocksize = offsetof(struct funcnode, n);
+       funcstringsize = 0;
+       calcsize(n);
+       blocksize = funcblocksize;
+       f = ckmalloc(blocksize + funcstringsize);
+       funcblock = (char *) f + offsetof(struct funcnode, n);
+       funcstring = (char *) f + blocksize;
+       copynode(n);
+       f->count = 0;
+       return f;
+}
 
-               if (num > shellparam.nparam)
-                       return 0;
+/*
+ * Define a shell function.
+ */
 
-               if (num == 0)
-                       ap = arg0;
-               else
-                       ap = shellparam.p[num - 1];
+static void
+defun(char *name, union node *func)
+{
+       struct cmdentry entry;
 
-               if (nulok && (ap == NULL || *ap == '\0'))
-                       return 0;
-       }
-       return 1;
+       INTOFF;
+       entry.cmdtype = CMDFUNCTION;
+       entry.u.func = copyfunc(func);
+       addcmdentry(name, &entry);
+       INTON;
 }
 
+
 /*
- * Put a string on the stack.
+ * Delete a function if it exists.
  */
 
 static void
-strtodest(const char *p, int syntax, int quotes)
+unsetfunc(const char *name)
 {
-       while (*p) {
-               if (quotes && SIT(*p,syntax) == CCTL)
-                       STPUTC(CTLESC, expdest);
-               STPUTC(*p++, expdest);
-       }
+       struct tblentry *cmdp;
+
+       if ((cmdp = cmdlookup(name, 0)) != NULL &&
+           cmdp->cmdtype == CMDFUNCTION)
+               delete_cmd_entry();
 }
 
 /*
- * Add the value of a specialized variable to the stack string.
+ * Locate and print what a word is...
  */
 
-static inline void
-varvalue(char *name, int quoted, int flags)
+
+#ifdef CONFIG_ASH_CMDCMD
+static int
+describe_command(char *command, int describe_command_verbose)
+#else
+#define describe_command_verbose 1
+static int
+describe_command(char *command)
+#endif
 {
-       int num;
-       char *p;
-       int i;
-       int sep;
-       int sepq = 0;
-       char **ap;
-       int syntax;
-       int allow_split = flags & EXP_FULL;
-       int quotes = flags & (EXP_FULL | EXP_CASE);
+       struct cmdentry entry;
+       struct tblentry *cmdp;
+#ifdef CONFIG_ASH_ALIAS
+       const struct alias *ap;
+#endif
+       const char *path = pathval();
 
-       syntax = quoted ? DQSYNTAX : BASESYNTAX;
-       switch (*name) {
-       case '$':
-               num = rootpid;
-               goto numvar;
-       case '?':
-               num = oexitstatus;
-               goto numvar;
-       case '#':
-               num = shellparam.nparam;
-               goto numvar;
-       case '!':
-               num = backgndpid;
-numvar:
-               expdest = cvtnum(num, expdest);
-               break;
-       case '-':
-               for (i = 0 ; i < NOPTS ; i++) {
-                       if (optent_val(i))
-                               STPUTC(optent_letter(optlist[i]), expdest);
+       if (describe_command_verbose) {
+               out1str(command);
+       }
+
+       /* First look at the keywords */
+       if (findkwd(command)) {
+               out1str(describe_command_verbose ? " is a shell keyword" : command);
+               goto out;
+       }
+
+#ifdef CONFIG_ASH_ALIAS
+       /* Then look at the aliases */
+       if ((ap = lookupalias(command, 0)) != NULL) {
+               if (describe_command_verbose) {
+                       out1fmt(" is an alias for %s", ap->val);
+               } else {
+                       out1str("alias ");
+                       printalias(ap);
+                       return 0;
                }
-               break;
-       case '@':
-               if (allow_split && quoted) {
-                       sep = 1 << CHAR_BIT;
-                       goto param;
+               goto out;
+       }
+#endif
+       /* Then check if it is a tracked alias */
+       if ((cmdp = cmdlookup(command, 0)) != NULL) {
+               entry.cmdtype = cmdp->cmdtype;
+               entry.u = cmdp->param;
+       } else {
+               /* Finally use brute force */
+               find_command(command, &entry, DO_ABS, path);
+       }
+
+       switch (entry.cmdtype) {
+       case CMDNORMAL: {
+               int j = entry.u.index;
+               char *p;
+               if (j == -1) {
+                       p = command;
+               } else {
+                       do {
+                               p = padvance(&path, command);
+                               stunalloc(p);
+                       } while (--j >= 0);
                }
-               /* fall through */
-       case '*':
-               sep = ifsset() ? ifsval()[0] : ' ';
-               if (quotes) {
-                       sepq = SIT(sep,syntax) == CCTL;
+               if (describe_command_verbose) {
+                       out1fmt(" is%s %s",
+                               (cmdp ? " a tracked alias for" : nullstr), p
+                       );
+               } else {
+                       out1str(p);
                }
-param:
-               for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
-                       strtodest(p, syntax, quotes);
-                       if (*ap && sep) {
-                               if (sepq)
-                                       STPUTC(CTLESC, expdest);
-                               STPUTC(sep, expdest);
-                       }
+               break;
+       }
+
+       case CMDFUNCTION:
+               if (describe_command_verbose) {
+                       out1str(" is a shell function");
+               } else {
+                       out1str(command);
                }
                break;
-       case '0':
-               strtodest(arg0, syntax, quotes);
+
+       case CMDBUILTIN:
+               if (describe_command_verbose) {
+                       out1fmt(" is a %sshell builtin",
+                               IS_BUILTIN_SPECIAL(entry.u.cmd) ?
+                                       "special " : nullstr
+                       );
+               } else {
+                       out1str(command);
+               }
                break;
+
        default:
-               num = atoi(name);
-               if (num > 0 && num <= shellparam.nparam) {
-                       strtodest(shellparam.p[num - 1], syntax, quotes);
+               if (describe_command_verbose) {
+                       out1str(": not found\n");
                }
-               break;
+               return 127;
        }
-}
 
+out:
+       outstr("\n", stdout);
+       return 0;
+}
 
-/*
- * Record the fact that we have to scan this region of the
- * string for IFS characters.
- */
-
-static void
-recordregion(int start, int end, int nulonly)
+static int
+typecmd(int argc, char **argv)
 {
-       struct ifsregion *ifsp;
+       int i;
+       int err = 0;
 
-       if (ifslastp == NULL) {
-               ifsp = &ifsfirst;
-       } else {
-               INTOFF;
-               ifsp = (struct ifsregion *)xmalloc(sizeof (struct ifsregion));
-               ifsp->next = NULL;
-               ifslastp->next = ifsp;
-               INTON;
+       for (i = 1; i < argc; i++) {
+#ifdef CONFIG_ASH_CMDCMD
+               err |= describe_command(argv[i], 1);
+#else
+               err |= describe_command(argv[i]);
+#endif
        }
-       ifslastp = ifsp;
-       ifslastp->begoff = start;
-       ifslastp->endoff = end;
-       ifslastp->nulonly = nulonly;
+       return err;
 }
 
-
-
-/*
- * Break the argument string into pieces based upon IFS and add the
- * strings to the argument list.  The regions of the string to be
- * searched for IFS characters have been stored by recordregion.
- */
-static void
-ifsbreakup(char *string, struct arglist *arglist)
+#ifdef CONFIG_ASH_CMDCMD
+static int
+commandcmd(int argc, char **argv)
 {
-       struct ifsregion *ifsp;
-       struct strlist *sp;
-       char *start;
-       char *p;
-       char *q;
-       const char *ifs, *realifs;
-       int ifsspc;
-       int nulonly;
-
+       int c;
+       enum {
+               VERIFY_BRIEF = 1,
+               VERIFY_VERBOSE = 2,
+       } verify = 0;
 
-       start = string;
-       ifsspc = 0;
-       nulonly = 0;
-       realifs = ifsset() ? ifsval() : defifs;
-       if (ifslastp != NULL) {
-               ifsp = &ifsfirst;
-               do {
-                       p = string + ifsp->begoff;
-                       nulonly = ifsp->nulonly;
-                       ifs = nulonly ? nullstr : realifs;
-                       ifsspc = 0;
-                       while (p < string + ifsp->endoff) {
-                               q = p;
-                               if (*p == CTLESC)
-                                       p++;
-                               if (strchr(ifs, *p)) {
-                                       if (!nulonly)
-                                               ifsspc = (strchr(defifs, *p) != NULL);
-                                       /* Ignore IFS whitespace at start */
-                                       if (q == start && ifsspc) {
-                                               p++;
-                                               start = p;
-                                               continue;
-                                       }
-                                       *q = '\0';
-                                       sp = (struct strlist *)stalloc(sizeof *sp);
-                                       sp->text = start;
-                                       *arglist->lastp = sp;
-                                       arglist->lastp = &sp->next;
-                                       p++;
-                                       if (!nulonly) {
-                                               for (;;) {
-                                                       if (p >= string + ifsp->endoff) {
-                                                               break;
-                                                       }
-                                                       q = p;
-                                                       if (*p == CTLESC)
-                                                               p++;
-                                                       if (strchr(ifs, *p) == NULL ) {
-                                                               p = q;
-                                                               break;
-                                                       } else if (strchr(defifs, *p) == NULL) {
-                                                               if (ifsspc) {
-                                                                       p++;
-                                                                       ifsspc = 0;
-                                                               } else {
-                                                                       p = q;
-                                                                       break;
-                                                               }
-                                                       } else
-                                                               p++;
-                                               }
-                                       }
-                                       start = p;
-                               } else
-                                       p++;
-                       }
-               } while ((ifsp = ifsp->next) != NULL);
-               if (!(*start || (!ifsspc && start > string && nulonly))) {
-                       return;
-               }
-       }
+       while ((c = nextopt("pvV")) != '\0')
+               if (c == 'V')
+                       verify |= VERIFY_VERBOSE;
+               else if (c == 'v')
+                       verify |= VERIFY_BRIEF;
+#ifdef DEBUG
+               else if (c != 'p')
+                       abort();
+#endif
+       if (verify)
+               return describe_command(*argptr, verify - VERIFY_BRIEF);
 
-       sp = (struct strlist *)stalloc(sizeof *sp);
-       sp->text = start;
-       *arglist->lastp = sp;
-       arglist->lastp = &sp->next;
+       return 0;
 }
+#endif
 
-static void
-ifsfree(void)
-{
-       while (ifsfirst.next != NULL) {
-               struct ifsregion *ifsp;
-               INTOFF;
-               ifsp = ifsfirst.next->next;
-               ckfree(ifsfirst.next);
-               ifsfirst.next = ifsp;
-               INTON;
-       }
-       ifslastp = NULL;
-       ifsfirst.next = NULL;
-}
+/*      expand.c     */
 
 /*
- * Add a file name to the list.
+ * Routines to expand arguments to commands.  We have to deal with
+ * backquotes, shell variables, and file metacharacters.
  */
 
-static void
-addfname(const char *name)
-{
-       struct strlist *sp;
-
-       sp = (struct strlist *)stalloc(sizeof *sp);
-       sp->text = sstrdup(name);
-       *exparg.lastp = sp;
-       exparg.lastp = &sp->next;
-}
+/*
+ * _rmescape() flags
+ */
+#define RMESCAPE_ALLOC  0x1     /* Allocate a new string */
+#define RMESCAPE_GLOB   0x2     /* Add backslashes for glob */
+#define RMESCAPE_QUOTED 0x4     /* Remove CTLESC unless in quotes */
+#define RMESCAPE_GROW   0x8     /* Grow strings instead of stalloc */
+#define RMESCAPE_HEAP   0x10    /* Malloc strings instead of stalloc */
 
 /*
- * Expand shell metacharacters.  At this point, the only control characters
- * should be escapes.  The results are stored in the list exparg.
+ * Structure specifying which parts of the string should be searched
+ * for IFS characters.
  */
 
-#if defined(__GLIBC__) && __GLIBC__ >= 2 && !defined(FNMATCH_BROKEN) && !defined(GLOB_BROKEN)
-static void
-expandmeta(struct strlist *str, int flag)
-{
-       const char *p;
-       glob_t pglob;
-       /* TODO - EXP_REDIR */
+struct ifsregion {
+       struct ifsregion *next; /* next region in list */
+       int begoff;             /* offset of start of region */
+       int endoff;             /* offset of end of region */
+       int nulonly;            /* search for nul bytes only */
+};
 
-       while (str) {
-               if (fflag)
-                       goto nometa;
-               p = preglob(str->text);
-               INTOFF;
-               switch (glob(p, 0, 0, &pglob)) {
-               case 0:
-                       if(pglob.gl_pathv[1]==0 && !strcmp(p, pglob.gl_pathv[0]))
-                               goto nometa2;
-                       addglob(&pglob);
-                       globfree(&pglob);
-                       INTON;
-                       break;
-               case GLOB_NOMATCH:
-nometa2:
-                       globfree(&pglob);
-                       INTON;
-nometa:
-                       *exparg.lastp = str;
-                       rmescapes(str->text);
-                       exparg.lastp = &str->next;
-                       break;
-               default:        /* GLOB_NOSPACE */
-                       error("Out of space");
-               }
-               str = str->next;
+/* output of current string */
+static char *expdest;
+/* list of back quote expressions */
+static struct nodelist *argbackq;
+/* first struct in list of ifs regions */
+static struct ifsregion ifsfirst;
+/* last struct in list */
+static struct ifsregion *ifslastp;
+/* holds expanded arg list */
+static struct arglist exparg;
+
+static void argstr(char *, int);
+static char *exptilde(char *, char *, int);
+static void expbackq(union node *, int, int);
+static const char *subevalvar(char *, char *, int, int, int, int, int);
+static char *evalvar(char *, int);
+static void strtodest(const char *, int, int);
+static void memtodest(const char *p, size_t len, int syntax, int quotes);
+static ssize_t varvalue(char *, int, int);
+static void recordregion(int, int, int);
+static void removerecordregions(int);
+static void ifsbreakup(char *, struct arglist *);
+static void ifsfree(void);
+static void expandmeta(struct strlist *, int);
+static int patmatch(char *, const char *);
+
+static int cvtnum(arith_t);
+static size_t esclen(const char *, const char *);
+static char *scanleft(char *, char *, char *, char *, int, int);
+static char *scanright(char *, char *, char *, char *, int, int);
+static void varunset(const char *, const char *, const char *, int)
+       ATTRIBUTE_NORETURN;
+
+
+#define pmatch(a, b) !fnmatch((a), (b), 0)
+/*
+ * Prepare a pattern for a expmeta (internal glob(3)) call.
+ *
+ * Returns an stalloced string.
+ */
+
+static inline char *
+preglob(const char *pattern, int quoted, int flag) {
+       flag |= RMESCAPE_GLOB;
+       if (quoted) {
+               flag |= RMESCAPE_QUOTED;
+       }
+       return _rmescapes((char *)pattern, flag);
+}
+
+
+static size_t
+esclen(const char *start, const char *p) {
+       size_t esc = 0;
+
+       while (p > start && *--p == CTLESC) {
+               esc++;
        }
+       return esc;
 }
 
 
 /*
- * Add the result of glob(3) to the list.
+ * Expand shell variables and backquotes inside a here document.
  */
 
 static inline void
-addglob(const glob_t *pglob)
+expandhere(union node *arg, int fd)
 {
-       char **p = pglob->gl_pathv;
-
-       do {
-               addfname(*p);
-       } while (*++p);
+       herefd = fd;
+       expandarg(arg, (struct arglist *)NULL, 0);
+       full_write(fd, stackblock(), expdest - (char *)stackblock());
 }
 
 
-#else   /* defined(__GLIBC__) && !defined(FNMATCH_BROKEN) && !defined(GLOB_BROKEN) */
-static char *expdir;
-
+/*
+ * Perform variable substitution and command substitution on an argument,
+ * placing the resulting list of arguments in arglist.  If EXP_FULL is true,
+ * perform splitting and file name expansion.  When arglist is NULL, perform
+ * here document expansion.
+ */
 
-static void
-expandmeta(struct strlist *str, int flag)
+void
+expandarg(union node *arg, struct arglist *arglist, int flag)
 {
-       char *p;
-       struct strlist **savelastp;
        struct strlist *sp;
-       char c;
-       /* TODO - EXP_REDIR */
-
-       while (str) {
-               if (fflag)
-                       goto nometa;
-               p = str->text;
-               for (;;) {                      /* fast check for meta chars */
-                       if ((c = *p++) == '\0')
-                               goto nometa;
-                       if (c == '*' || c == '?' || c == '[' || c == '!')
-                               break;
-               }
-               savelastp = exparg.lastp;
-               INTOFF;
-               if (expdir == NULL) {
-                       int i = strlen(str->text);
-                       expdir = xmalloc(i < 2048 ? 2048 : i); /* XXX */
-               }
+       char *p;
 
-               expmeta(expdir, str->text);
-               ckfree(expdir);
-               expdir = NULL;
-               INTON;
-               if (exparg.lastp == savelastp) {
-                       /*
-                        * no matches
-                        */
-nometa:
-                       *exparg.lastp = str;
-                       rmescapes(str->text);
-                       exparg.lastp = &str->next;
-               } else {
-                       *exparg.lastp = NULL;
-                       *savelastp = sp = expsort(*savelastp);
-                       while (sp->next != NULL)
-                               sp = sp->next;
-                       exparg.lastp = &sp->next;
-               }
-               str = str->next;
+       argbackq = arg->narg.backquote;
+       STARTSTACKSTR(expdest);
+       ifsfirst.next = NULL;
+       ifslastp = NULL;
+       argstr(arg->narg.text, flag);
+       p = _STPUTC('\0', expdest);
+       expdest = p - 1;
+       if (arglist == NULL) {
+               return;                 /* here document expanded */
+       }
+       p = grabstackstr(p);
+       exparg.lastp = &exparg.list;
+       /*
+        * TODO - EXP_REDIR
+        */
+       if (flag & EXP_FULL) {
+               ifsbreakup(p, &exparg);
+               *exparg.lastp = NULL;
+               exparg.lastp = &exparg.list;
+               expandmeta(exparg.list, flag);
+       } else {
+               if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */
+                       rmescapes(p);
+               sp = (struct strlist *)stalloc(sizeof (struct strlist));
+               sp->text = p;
+               *exparg.lastp = sp;
+               exparg.lastp = &sp->next;
+       }
+       if (ifsfirst.next)
+               ifsfree();
+       *exparg.lastp = NULL;
+       if (exparg.list) {
+               *arglist->lastp = exparg.list;
+               arglist->lastp = exparg.lastp;
        }
 }
 
 
 /*
- * Do metacharacter (i.e. *, ?, [...]) expansion.
+ * Perform variable and command substitution.  If EXP_FULL is set, output CTLESC
+ * characters to allow for further processing.  Otherwise treat
+ * $@ like $* since no splitting will be performed.
  */
 
 static void
-expmeta(char *enddir, char *name)
+argstr(char *p, int flag)
 {
-       char *p;
-       const char *cp;
-       char *q;
-       char *start;
-       char *endname;
-       int metaflag;
-       struct stat statb;
-       DIR *dirp;
-       struct dirent *dp;
-       int atend;
-       int matchdot;
+       static const char spclchars[] = {
+               '=',
+               ':',
+               CTLQUOTEMARK,
+               CTLENDVAR,
+               CTLESC,
+               CTLVAR,
+               CTLBACKQ,
+               CTLBACKQ | CTLQUOTE,
+#ifdef CONFIG_ASH_MATH_SUPPORT
+               CTLENDARI,
+#endif
+               0
+       };
+       const char *reject = spclchars;
+       int c;
+       int quotes = flag & (EXP_FULL | EXP_CASE);      /* do CTLESC */
+       int breakall = flag & EXP_WORD;
+       int inquotes;
+       size_t length;
+       int startloc;
 
-       metaflag = 0;
-       start = name;
-       for (p = name ; ; p++) {
-               if (*p == '*' || *p == '?')
-                       metaflag = 1;
-               else if (*p == '[') {
-                       q = p + 1;
-                       if (*q == '!')
-                               q++;
-                       for (;;) {
-                               while (*q == CTLQUOTEMARK)
-                                       q++;
-                               if (*q == CTLESC)
-                                       q++;
-                               if (*q == '/' || *q == '\0')
-                                       break;
-                               if (*++q == ']') {
-                                       metaflag = 1;
-                                       break;
-                               }
-                       }
-               } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) {
-                       metaflag = 1;
-               } else if (*p == '\0')
-                       break;
-               else if (*p == CTLQUOTEMARK)
-                       continue;
-               else if (*p == CTLESC)
-                       p++;
-               if (*p == '/') {
-                       if (metaflag)
-                               break;
-                       start = p + 1;
-               }
+       if (!(flag & EXP_VARTILDE)) {
+               reject += 2;
+       } else if (flag & EXP_VARTILDE2) {
+               reject++;
        }
-       if (metaflag == 0) {    /* we've reached the end of the file name */
-               if (enddir != expdir)
-                       metaflag++;
-               for (p = name ; ; p++) {
-                       if (*p == CTLQUOTEMARK)
-                               continue;
-                       if (*p == CTLESC)
-                               p++;
-                       *enddir++ = *p;
-                       if (*p == '\0')
-                               break;
-               }
-               if (metaflag == 0 || lstat(expdir, &statb) >= 0)
-                       addfname(expdir);
-               return;
+       inquotes = 0;
+       length = 0;
+       if (flag & EXP_TILDE) {
+               char *q;
+
+               flag &= ~EXP_TILDE;
+tilde:
+               q = p;
+               if (*q == CTLESC && (flag & EXP_QWORD))
+                       q++;
+               if (*q == '~')
+                       p = exptilde(p, q, flag);
        }
-       endname = p;
-       if (start != name) {
-               p = name;
-               while (p < start) {
-                       while (*p == CTLQUOTEMARK)
-                               p++;
-                       if (*p == CTLESC)
-                               p++;
-                       *enddir++ = *p++;
+start:
+       startloc = expdest - (char *)stackblock();
+       for (;;) {
+               length += strcspn(p + length, reject);
+               c = p[length];
+               if (c && (!(c & 0x80)
+#ifdef CONFIG_ASH_MATH_SUPPORT
+                                       || c == CTLENDARI
+#endif
+                  )) {
+                       /* c == '=' || c == ':' || c == CTLENDARI */
+                       length++;
+               }
+               if (length > 0) {
+                       int newloc;
+                       expdest = stnputs(p, length, expdest);
+                       newloc = expdest - (char *)stackblock();
+                       if (breakall && !inquotes && newloc > startloc) {
+                               recordregion(startloc, newloc, 0);
+                       }
+                       startloc = newloc;
                }
-       }
-       if (enddir == expdir) {
-               cp = ".";
-       } else if (enddir == expdir + 1 && *expdir == '/') {
-               cp = "/";
-       } else {
-               cp = expdir;
-               enddir[-1] = '\0';
-       }
-       if ((dirp = opendir(cp)) == NULL)
-               return;
-       if (enddir != expdir)
-               enddir[-1] = '/';
-       if (*endname == 0) {
-               atend = 1;
-       } else {
-               atend = 0;
-               *endname++ = '\0';
-       }
-       matchdot = 0;
-       p = start;
-       while (*p == CTLQUOTEMARK)
-               p++;
-       if (*p == CTLESC)
-               p++;
-       if (*p == '.')
-               matchdot++;
-       while (! int_pending() && (dp = readdir(dirp)) != NULL) {
-               if (dp->d_name[0] == '.' && ! matchdot)
+               p += length + 1;
+               length = 0;
+
+               switch (c) {
+               case '\0':
+                       goto breakloop;
+               case '=':
+                       if (flag & EXP_VARTILDE2) {
+                               p--;
+                               continue;
+                       }
+                       flag |= EXP_VARTILDE2;
+                       reject++;
+                       /* fall through */
+               case ':':
+                       /*
+                        * sort of a hack - expand tildes in variable
+                        * assignments (after the first '=' and after ':'s).
+                        */
+                       if (*--p == '~') {
+                               goto tilde;
+                       }
                        continue;
-               if (patmatch(start, dp->d_name, 0)) {
-                       if (atend) {
-                               strcpy(enddir, dp->d_name);
-                               addfname(expdir);
-                       } else {
-                               for (p = enddir, cp = dp->d_name;
-                                    (*p++ = *cp++) != '\0';)
-                                       continue;
-                               p[-1] = '/';
-                               expmeta(p, endname);
+               }
+
+               switch (c) {
+               case CTLENDVAR: /* ??? */
+                       goto breakloop;
+               case CTLQUOTEMARK:
+                       /* "$@" syntax adherence hack */
+                       if (
+                               !inquotes &&
+                               !memcmp(p, dolatstr, DOLATSTRLEN) &&
+                               (p[4] == CTLQUOTEMARK || (
+                                       p[4] == CTLENDVAR &&
+                                       p[5] == CTLQUOTEMARK
+                               ))
+                       ) {
+                               p = evalvar(p + 1, flag) + 1;
+                               goto start;
+                       }
+                       inquotes = !inquotes;
+addquote:
+                       if (quotes) {
+                               p--;
+                               length++;
+                               startloc++;
                        }
+                       break;
+               case CTLESC:
+                       startloc++;
+                       length++;
+                       goto addquote;
+               case CTLVAR:
+                       p = evalvar(p, flag);
+                       goto start;
+               case CTLBACKQ:
+                       c = 0;
+               case CTLBACKQ|CTLQUOTE:
+                       expbackq(argbackq->n, c, quotes);
+                       argbackq = argbackq->next;
+                       goto start;
+#ifdef CONFIG_ASH_MATH_SUPPORT
+               case CTLENDARI:
+                       p--;
+                       expari(quotes);
+                       goto start;
+#endif
                }
        }
-       closedir(dirp);
-       if (! atend)
-               endname[-1] = '/';
+breakloop:
+       ;
 }
-#endif  /* defined(__GLIBC__) && !defined(FNMATCH_BROKEN) && !defined(GLOB_BROKEN) */
-
-
-
-#if !(defined(__GLIBC__) && __GLIBC__ >= 2 && !defined(FNMATCH_BROKEN) && !defined(GLOB_BROKEN))
-/*
- * Sort the results of file name expansion.  It calculates the number of
- * strings to sort and then calls msort (short for merge sort) to do the
- * work.
- */
 
-static struct strlist *
-expsort(struct strlist *str)
+static char *
+exptilde(char *startp, char *p, int flag)
 {
-       int len;
-       struct strlist *sp;
+       char c;
+       char *name;
+       struct passwd *pw;
+       const char *home;
+       int quotes = flag & (EXP_FULL | EXP_CASE);
+       int startloc;
 
-       len = 0;
-       for (sp = str ; sp ; sp = sp->next)
-               len++;
-       return msort(str, len);
+       name = p + 1;
+
+       while ((c = *++p) != '\0') {
+               switch(c) {
+               case CTLESC:
+                       return (startp);
+               case CTLQUOTEMARK:
+                       return (startp);
+               case ':':
+                       if (flag & EXP_VARTILDE)
+                               goto done;
+                       break;
+               case '/':
+               case CTLENDVAR:
+                       goto done;
+               }
+       }
+done:
+       *p = '\0';
+       if (*name == '\0') {
+               home = lookupvar(homestr);
+       } else {
+               if ((pw = getpwnam(name)) == NULL)
+                       goto lose;
+               home = pw->pw_dir;
+       }
+       if (!home || !*home)
+               goto lose;
+       *p = c;
+       startloc = expdest - (char *)stackblock();
+       strtodest(home, SQSYNTAX, quotes);
+       recordregion(startloc, expdest - (char *)stackblock(), 0);
+       return (p);
+lose:
+       *p = c;
+       return (startp);
 }
 
 
-static struct strlist *
-msort(struct strlist *list, int len)
+static void
+removerecordregions(int endoff)
 {
-       struct strlist *p, *q = NULL;
-       struct strlist **lpp;
-       int half;
-       int n;
+       if (ifslastp == NULL)
+               return;
 
-       if (len <= 1)
-               return list;
-       half = len >> 1;
-       p = list;
-       for (n = half ; --n >= 0 ; ) {
-               q = p;
-               p = p->next;
-       }
-       q->next = NULL;                 /* terminate first half of list */
-       q = msort(list, half);          /* sort first half of list */
-       p = msort(p, len - half);               /* sort second half */
-       lpp = &list;
-       for (;;) {
-               if (strcmp(p->text, q->text) < 0) {
-                       *lpp = p;
-                       lpp = &p->next;
-                       if ((p = *lpp) == NULL) {
-                               *lpp = q;
-                               break;
-                       }
-               } else {
-                       *lpp = q;
-                       lpp = &q->next;
-                       if ((q = *lpp) == NULL) {
-                               *lpp = p;
-                               break;
-                       }
+       if (ifsfirst.endoff > endoff) {
+               while (ifsfirst.next != NULL) {
+                       struct ifsregion *ifsp;
+                       INTOFF;
+                       ifsp = ifsfirst.next->next;
+                       ckfree(ifsfirst.next);
+                       ifsfirst.next = ifsp;
+                       INTON;
+               }
+               if (ifsfirst.begoff > endoff)
+                       ifslastp = NULL;
+               else {
+                       ifslastp = &ifsfirst;
+                       ifsfirst.endoff = endoff;
                }
+               return;
        }
-       return list;
-}
-#endif
 
+       ifslastp = &ifsfirst;
+       while (ifslastp->next && ifslastp->next->begoff < endoff)
+               ifslastp=ifslastp->next;
+       while (ifslastp->next != NULL) {
+               struct ifsregion *ifsp;
+               INTOFF;
+               ifsp = ifslastp->next->next;
+               ckfree(ifslastp->next);
+               ifslastp->next = ifsp;
+               INTON;
+       }
+       if (ifslastp->endoff > endoff)
+               ifslastp->endoff = endoff;
+}
 
 
+#ifdef CONFIG_ASH_MATH_SUPPORT
 /*
- * Returns true if the pattern matches the string.
+ * Expand arithmetic expression.  Backup to start of expression,
+ * evaluate, place result in (backed up) result, adjust string position.
  */
-
-#if defined(__GLIBC__) && __GLIBC__ >= 2 && !defined(FNMATCH_BROKEN)
-/* squoted: string might have quote chars */
-static int
-patmatch(char *pattern, char *string, int squoted)
+void
+expari(int quotes)
 {
-       const char *p;
-       char *q;
+       char *p, *start;
+       int begoff;
+       int flag;
+       int len;
 
-       p = preglob(pattern);
-       q = squoted ? _rmescapes(string, RMESCAPE_ALLOC) : string;
+       /*      ifsfree(); */
 
-       return !fnmatch(p, q, 0);
-}
+       /*
+        * This routine is slightly over-complicated for
+        * efficiency.  Next we scan backwards looking for the
+        * start of arithmetic.
+        */
+       start = stackblock();
+       p = expdest - 1;
+       *p = '\0';
+       p--;
+       do {
+               int esc;
 
+               while (*p != CTLARI) {
+                       p--;
+#ifdef DEBUG
+                       if (p < start) {
+                               sh_error("missing CTLARI (shouldn't happen)");
+                       }
+#endif
+               }
 
-static int
-patmatch2(char *pattern, char *string, int squoted)
-{
-       char *p;
-       int res;
+               esc = esclen(start, p);
+               if (!(esc % 2)) {
+                       break;
+               }
 
-       sstrnleft--;
-       p = grabstackstr(expdest);
-       res = patmatch(pattern, string, squoted);
-       ungrabstackstr(p, expdest);
-       return res;
-}
-#else
-static int
-patmatch(char *pattern, char *string, int squoted) {
-       return pmatch(pattern, string, squoted);
+               p -= esc + 1;
+       } while (1);
+
+       begoff = p - start;
+
+       removerecordregions(begoff);
+
+       flag = p[1];
+
+       expdest = p;
+
+       if (quotes)
+               rmescapes(p + 2);
+
+       len = cvtnum(dash_arith(p + 2));
+
+       if (flag != '"')
+               recordregion(begoff, begoff + len, 0);
 }
+#endif
 
+/*
+ * Expand stuff in backwards quotes.
+ */
 
-static int
-pmatch(char *pattern, char *string, int squoted)
+static void
+expbackq(union node *cmd, int quoted, int quotes)
 {
-       char *p, *q;
-       char c;
+       struct backcmd in;
+       int i;
+       char buf[128];
+       char *p;
+       char *dest;
+       int startloc;
+       int syntax = quoted? DQSYNTAX : BASESYNTAX;
+       struct stackmark smark;
+
+       INTOFF;
+       setstackmark(&smark);
+       dest = expdest;
+       startloc = dest - (char *)stackblock();
+       grabstackstr(dest);
+       evalbackcmd(cmd, (struct backcmd *) &in);
+       popstackmark(&smark);
 
-       p = pattern;
-       q = string;
+       p = in.buf;
+       i = in.nleft;
+       if (i == 0)
+               goto read;
        for (;;) {
-               switch (c = *p++) {
-               case '\0':
-                       goto breakloop;
-               case CTLESC:
-                       if (squoted && *q == CTLESC)
-                               q++;
-                       if (*q++ != *p++)
-                               return 0;
-                       break;
-               case CTLQUOTEMARK:
-                       continue;
-               case '?':
-                       if (squoted && *q == CTLESC)
-                               q++;
-                       if (*q++ == '\0')
-                               return 0;
-                       break;
-               case '*':
-                       c = *p;
-                       while (c == CTLQUOTEMARK || c == '*')
-                               c = *++p;
-                       if (c != CTLESC &&  c != CTLQUOTEMARK &&
-                           c != '?' && c != '*' && c != '[') {
-                               while (*q != c) {
-                                       if (squoted && *q == CTLESC &&
-                                           q[1] == c)
-                                               break;
-                                       if (*q == '\0')
-                                               return 0;
-                                       if (squoted && *q == CTLESC)
-                                               q++;
-                                       q++;
-                               }
-                       }
-                       do {
-                               if (pmatch(p, q, squoted))
-                                       return 1;
-                               if (squoted && *q == CTLESC)
-                                       q++;
-                       } while (*q++ != '\0');
-                       return 0;
-               case '[': {
-                       char *endp;
-                       int invert, found;
-                       char chr;
-
-                       endp = p;
-                       if (*endp == '!')
-                               endp++;
-                       for (;;) {
-                               while (*endp == CTLQUOTEMARK)
-                                       endp++;
-                               if (*endp == '\0')
-                                       goto dft;               /* no matching ] */
-                               if (*endp == CTLESC)
-                                       endp++;
-                               if (*++endp == ']')
-                                       break;
-                       }
-                       invert = 0;
-                       if (*p == '!') {
-                               invert++;
-                               p++;
-                       }
-                       found = 0;
-                       chr = *q++;
-                       if (squoted && chr == CTLESC)
-                               chr = *q++;
-                       if (chr == '\0')
-                               return 0;
-                       c = *p++;
-                       do {
-                               if (c == CTLQUOTEMARK)
-                                       continue;
-                               if (c == CTLESC)
-                                       c = *p++;
-                               if (*p == '-' && p[1] != ']') {
-                                       p++;
-                                       while (*p == CTLQUOTEMARK)
-                                               p++;
-                                       if (*p == CTLESC)
-                                               p++;
-                                       if (chr >= c && chr <= *p)
-                                               found = 1;
-                                       p++;
-                               } else {
-                                       if (chr == c)
-                                               found = 1;
-                               }
-                       } while ((c = *p++) != ']');
-                       if (found == invert)
-                               return 0;
+               memtodest(p, i, syntax, quotes);
+read:
+               if (in.fd < 0)
                        break;
-               }
-dft:            default:
-                       if (squoted && *q == CTLESC)
-                               q++;
-                       if (*q++ != c)
-                               return 0;
+               i = safe_read(in.fd, buf, sizeof buf);
+               TRACE(("expbackq: read returns %d\n", i));
+               if (i <= 0)
                        break;
-               }
+               p = buf;
        }
-breakloop:
-       if (*q != '\0')
-               return 0;
-       return 1;
-}
-#endif
 
+       if (in.buf)
+               ckfree(in.buf);
+       if (in.fd >= 0) {
+               close(in.fd);
+               back_exitstatus = waitforjob(in.jp);
+       }
+       INTON;
+
+       /* Eat all trailing newlines */
+       dest = expdest;
+       for (; dest > (char *)stackblock() && dest[-1] == '\n';)
+               STUNPUTC(dest);
+       expdest = dest;
 
+       if (quoted == 0)
+               recordregion(startloc, dest - (char *)stackblock(), 0);
+       TRACE(("evalbackq: size=%d: \"%.*s\"\n",
+               (dest - (char *)stackblock()) - startloc,
+               (dest - (char *)stackblock()) - startloc,
+               stackblock() + startloc));
+}
 
-/*
- * Remove any CTLESC characters from a string.
- */
 
-#if defined(__GLIBC__) && __GLIBC__ >= 2 && !defined(FNMATCH_BROKEN)
 static char *
-_rmescapes(char *str, int flag)
+scanleft(char *startp, char *rmesc, char *rmescend, char *str, int quotes,
+       int zero)
 {
-       char *p, *q, *r;
-       static const char qchars[] = { CTLESC, CTLQUOTEMARK, 0 };
+       char *loc;
+       char *loc2;
+       char c;
 
-       p = strpbrk(str, qchars);
-       if (!p) {
-               return str;
-       }
-       q = p;
-       r = str;
-       if (flag & RMESCAPE_ALLOC) {
-               size_t len = p - str;
-               q = r = stalloc(strlen(p) + len + 1);
-               if (len > 0) {
-                       memcpy(q, str, len);
-                       q += len;
-               }
-       }
-       while (*p) {
-               if (*p == CTLQUOTEMARK) {
-                       p++;
-                       continue;
-               }
-               if (*p == CTLESC) {
-                       p++;
-                       if (flag & RMESCAPE_GLOB && *p != '/') {
-                               *q++ = '\\';
+       loc = startp;
+       loc2 = rmesc;
+       do {
+               int match;
+               const char *s = loc2;
+               c = *loc2;
+               if (zero) {
+                       *loc2 = '\0';
+                       s = rmesc;
+               }
+               match = pmatch(str, s);
+               *loc2 = c;
+               if (match)
+                       return loc;
+               if (quotes && *loc == CTLESC)
+                       loc++;
+               loc++;
+               loc2++;
+       } while (c);
+       return 0;
+}
+
+
+static char *
+scanright(char *startp, char *rmesc, char *rmescend, char *str, int quotes,
+       int zero)
+{
+       int esc = 0;
+       char *loc;
+       char *loc2;
+
+       for (loc = str - 1, loc2 = rmescend; loc >= startp; loc2--) {
+               int match;
+               char c = *loc2;
+               const char *s = loc2;
+               if (zero) {
+                       *loc2 = '\0';
+                       s = rmesc;
+               }
+               match = pmatch(str, s);
+               *loc2 = c;
+               if (match)
+                       return loc;
+               loc--;
+               if (quotes) {
+                       if (--esc < 0) {
+                               esc = esclen(startp, loc);
+                       }
+                       if (esc % 2) {
+                               esc--;
+                               loc--;
                        }
                }
-               *q++ = *p++;
        }
-       *q = '\0';
-       return r;
+       return 0;
 }
-#else
-static void
-rmescapes(char *str)
+
+static const char *
+subevalvar(char *p, char *str, int strloc, int subtype, int startloc, int varflags, int quotes)
 {
-       char *p, *q;
+       char *startp;
+       char *loc;
+       int saveherefd = herefd;
+       struct nodelist *saveargbackq = argbackq;
+       int amount;
+       char *rmesc, *rmescend;
+       int zero;
+       char *(*scan)(char *, char *, char *, char *, int , int);
 
-       p = str;
-       while (*p != CTLESC && *p != CTLQUOTEMARK) {
-               if (*p++ == '\0')
-                       return;
+       herefd = -1;
+       argstr(p, subtype != VSASSIGN && subtype != VSQUESTION ? EXP_CASE : 0);
+       STPUTC('\0', expdest);
+       herefd = saveherefd;
+       argbackq = saveargbackq;
+       startp = stackblock() + startloc;
+
+       switch (subtype) {
+       case VSASSIGN:
+               setvar(str, startp, 0);
+               amount = startp - expdest;
+               STADJUST(amount, expdest);
+               return startp;
+
+       case VSQUESTION:
+               varunset(p, str, startp, varflags);
+               /* NOTREACHED */
        }
-       q = p;
-       while (*p) {
-               if (*p == CTLQUOTEMARK) {
-                       p++;
-                       continue;
+
+       subtype -= VSTRIMRIGHT;
+#ifdef DEBUG
+       if (subtype < 0 || subtype > 3)
+               abort();
+#endif
+
+       rmesc = startp;
+       rmescend = stackblock() + strloc;
+       if (quotes) {
+               rmesc = _rmescapes(startp, RMESCAPE_ALLOC | RMESCAPE_GROW);
+               if (rmesc != startp) {
+                       rmescend = expdest;
+                       startp = stackblock() + startloc;
                }
-               if (*p == CTLESC)
-                       p++;
-               *q++ = *p++;
        }
-       *q = '\0';
-}
-#endif
+       rmescend--;
+       str = stackblock() + strloc;
+       preglob(str, varflags & VSQUOTE, 0);
 
+       /* zero = subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX */
+       zero = subtype >> 1;
+       /* VSTRIMLEFT/VSTRIMRIGHTMAX -> scanleft */
+       scan = (subtype & 1) ^ zero ? scanleft : scanright;
+
+       loc = scan(startp, rmesc, rmescend, str, quotes, zero);
+       if (loc) {
+               if (zero) {
+                       memmove(startp, loc, str - loc);
+                       loc = startp + (str - loc) - 1;
+               }
+               *loc = '\0';
+               amount = loc - expdest;
+               STADJUST(amount, expdest);
+       }
+       return loc;
+}
 
 
 /*
- * See if a pattern matches in a case statement.
+ * Expand a variable, and return a pointer to the next character in the
+ * input string.
  */
-
-static int
-casematch(union node *pattern, const char *val)
+static char *
+evalvar(char *p, int flag)
 {
-       struct stackmark smark;
-       int result;
-       char *p;
+       int subtype;
+       int varflags;
+       char *var;
+       int patloc;
+       int c;
+       int startloc;
+       ssize_t varlen;
+       int easy;
+       int quotes;
+       int quoted;
 
-       setstackmark(&smark);
-       argbackq = pattern->narg.backquote;
-       STARTSTACKSTR(expdest);
-       ifslastp = NULL;
-       argstr(pattern->narg.text, EXP_TILDE | EXP_CASE);
-       STPUTC('\0', expdest);
-       p = grabstackstr(expdest);
-       result = patmatch(p, (char *)val, 0);
-       popstackmark(&smark);
-       return result;
-}
+       quotes = flag & (EXP_FULL | EXP_CASE);
+       varflags = *p++;
+       subtype = varflags & VSTYPE;
+       quoted = varflags & VSQUOTE;
+       var = p;
+       easy = (!quoted || (*var == '@' && shellparam.nparam));
+       startloc = expdest - (char *)stackblock();
+       p = strchr(p, '=') + 1;
 
-/*
- * Our own itoa().
- */
+again:
+       varlen = varvalue(var, varflags, flag);
+       if (varflags & VSNUL)
+               varlen--;
 
-static char *
-cvtnum(int num, char *buf)
-{
-       int len;
+       if (subtype == VSPLUS) {
+               varlen = -1 - varlen;
+               goto vsplus;
+       }
 
-       CHECKSTRSPACE(32, buf);
-       len = sprintf(buf, "%d", num);
-       STADJUST(len, buf);
-       return buf;
-}
-/*
- * Editline and history functions (and glue).
- */
-static int histcmd(int argc, char **argv)
-{
-       error("not compiled with history support");
-       /* NOTREACHED */
-}
+       if (subtype == VSMINUS) {
+vsplus:
+               if (varlen < 0) {
+                       argstr(
+                               p, flag | EXP_TILDE |
+                                       (quoted ?  EXP_QWORD : EXP_WORD)
+                       );
+                       goto end;
+               }
+               if (easy)
+                       goto record;
+               goto end;
+       }
 
+       if (subtype == VSASSIGN || subtype == VSQUESTION) {
+               if (varlen < 0) {
+                       if (subevalvar(p, var, 0, subtype, startloc,
+                                      varflags, 0)) {
+                               varflags &= ~VSNUL;
+                               /*
+                                * Remove any recorded regions beyond
+                                * start of variable
+                                */
+                               removerecordregions(startloc);
+                               goto again;
+                       }
+                       goto end;
+               }
+               if (easy)
+                       goto record;
+               goto end;
+       }
 
-struct redirtab {
-       struct redirtab *next;
-       short renamed[10]; /* Current ash support only 0-9 descriptors */
-       /* char on arm (and others) can't be negative */
-};
+       if (varlen < 0 && uflag)
+               varunset(p, var, 0, 0);
 
-static struct redirtab *redirlist;
+       if (subtype == VSLENGTH) {
+               cvtnum(varlen > 0 ? varlen : 0);
+               goto record;
+       }
 
-extern char **environ;
+       if (subtype == VSNORMAL) {
+               if (!easy)
+                       goto end;
+record:
+               recordregion(startloc, expdest - (char *)stackblock(), quoted);
+               goto end;
+       }
+
+#ifdef DEBUG
+       switch (subtype) {
+       case VSTRIMLEFT:
+       case VSTRIMLEFTMAX:
+       case VSTRIMRIGHT:
+       case VSTRIMRIGHTMAX:
+               break;
+       default:
+               abort();
+       }
+#endif
+
+       if (varlen >= 0) {
+               /*
+                * Terminate the string and start recording the pattern
+                * right after it
+                */
+               STPUTC('\0', expdest);
+               patloc = expdest - (char *)stackblock();
+               if (subevalvar(p, NULL, patloc, subtype,
+                              startloc, varflags, quotes) == 0) {
+                       int amount = expdest - (
+                               (char *)stackblock() + patloc - 1
+                       );
+                       STADJUST(-amount, expdest);
+               }
+               /* Remove any recorded regions beyond start of variable */
+               removerecordregions(startloc);
+               goto record;
+       }
 
+end:
+       if (subtype != VSNORMAL) {      /* skip to end of alternative */
+               int nesting = 1;
+               for (;;) {
+                       if ((c = *p++) == CTLESC)
+                               p++;
+                       else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
+                               if (varlen >= 0)
+                                       argbackq = argbackq->next;
+                       } else if (c == CTLVAR) {
+                               if ((*p++ & VSTYPE) != VSNORMAL)
+                                       nesting++;
+                       } else if (c == CTLENDVAR) {
+                               if (--nesting == 0)
+                                       break;
+                       }
+               }
+       }
+       return p;
+}
 
 
 /*
- * Initialization code.
+ * Put a string on the stack.
  */
 
 static void
-init(void) {
+memtodest(const char *p, size_t len, int syntax, int quotes) {
+       char *q = expdest;
 
-      /* from cd.c: */
-      {
-             curdir = nullstr;
-             setpwd(0, 0);
-      }
+       q = makestrspace(len * 2, q);
 
-      /* from input.c: */
-      {
-             basepf.nextc = basepf.buf = basebuf;
-      }
+       while (len--) {
+               int c = SC2INT(*p++);
+               if (!c)
+                       continue;
+               if (quotes && (SIT(c, syntax) == CCTL || SIT(c, syntax) == CBACK))
+                       USTPUTC(CTLESC, q);
+               USTPUTC(c, q);
+       }
 
-      /* from var.c: */
-      {
-             char **envp;
-             char ppid[32];
+       expdest = q;
+}
 
-             initvar();
-             for (envp = environ ; *envp ; envp++) {
-                     if (strchr(*envp, '=')) {
-                             setvareq(*envp, VEXPORT|VTEXTFIXED);
-                     }
-             }
 
-             snprintf(ppid, sizeof(ppid), "%d", (int) getppid());
-             setvar("PPID", ppid, 0);
-      }
+static void
+strtodest(const char *p, int syntax, int quotes)
+{
+       memtodest(p, strlen(p), syntax, quotes);
 }
 
 
-
 /*
- * This routine is called when an error or an interrupt occurs in an
- * interactive shell and control is returned to the main command loop.
+ * Add the value of a specialized variable to the stack string.
  */
 
-/* 1 == check for aliases, 2 == also check for assignments */
-static int checkalias;  /* also used in no alias mode for check assignments */
-
-static void
-reset(void) {
-
-      /* from eval.c: */
-      {
-             evalskip = 0;
-             loopnest = 0;
-             funcnest = 0;
-      }
+static ssize_t
+varvalue(char *name, int varflags, int flags)
+{
+       int num;
+       char *p;
+       int i;
+       int sep = 0;
+       int sepq = 0;
+       ssize_t len = 0;
+       char **ap;
+       int syntax;
+       int quoted = varflags & VSQUOTE;
+       int subtype = varflags & VSTYPE;
+       int quotes = flags & (EXP_FULL | EXP_CASE);
 
-      /* from input.c: */
-      {
-             if (exception != EXSHELLPROC)
-                     parselleft = parsenleft = 0;      /* clear input buffer */
-             popallfiles();
-      }
+       if (quoted && (flags & EXP_FULL))
+               sep = 1 << CHAR_BIT;
 
-      /* from parser.c: */
-      {
-             tokpushback = 0;
-             checkkwd = 0;
-             checkalias = 0;
-      }
+       syntax = quoted ? DQSYNTAX : BASESYNTAX;
+       switch (*name) {
+       case '$':
+               num = rootpid;
+               goto numvar;
+       case '?':
+               num = exitstatus;
+               goto numvar;
+       case '#':
+               num = shellparam.nparam;
+               goto numvar;
+       case '!':
+               num = backgndpid;
+               if (num == 0)
+                       return -1;
+numvar:
+               len = cvtnum(num);
+               break;
+       case '-':
+               p = makestrspace(NOPTS, expdest);
+               for (i = NOPTS - 1; i >= 0; i--) {
+                       if (optlist[i]) {
+                               USTPUTC(optletters(i), p);
+                               len++;
+                       }
+               }
+               expdest = p;
+               break;
+       case '@':
+               if (sep)
+                       goto param;
+               /* fall through */
+       case '*':
+               sep = ifsset() ? SC2INT(ifsval()[0]) : ' ';
+               if (quotes && (SIT(sep, syntax) == CCTL || SIT(sep, syntax) == CBACK))
+                       sepq = 1;
+param:
+               if (!(ap = shellparam.p))
+                       return -1;
+               while ((p = *ap++)) {
+                       size_t partlen;
 
-      /* from redir.c: */
-      {
-             while (redirlist)
-                     popredir();
-      }
+                       partlen = strlen(p);
+                       len += partlen;
 
-}
+                       if (!(subtype == VSPLUS || subtype == VSLENGTH))
+                               memtodest(p, partlen, syntax, quotes);
 
+                       if (*ap && sep) {
+                               char *q;
 
+                               len++;
+                               if (subtype == VSPLUS || subtype == VSLENGTH) {
+                                       continue;
+                               }
+                               q = expdest;
+                               if (sepq)
+                                       STPUTC(CTLESC, q);
+                               STPUTC(sep, q);
+                               expdest = q;
+                       }
+               }
+               return len;
+       case '0':
+       case '1':
+       case '2':
+       case '3':
+       case '4':
+       case '5':
+       case '6':
+       case '7':
+       case '8':
+       case '9':
+               num = atoi(name);
+               if (num < 0 || num > shellparam.nparam)
+                       return -1;
+               p = num ? shellparam.p[num - 1] : arg0;
+               goto value;
+       default:
+               p = lookupvar(name);
+value:
+               if (!p)
+                       return -1;
 
-/*
- * This file implements the input routines used by the parser.
- */
+               len = strlen(p);
+               if (!(subtype == VSPLUS || subtype == VSLENGTH))
+                       memtodest(p, len, syntax, quotes);
+               return len;
+       }
 
-#ifdef CONFIG_FEATURE_COMMAND_EDITING
-static const char * cmdedit_prompt;
-static inline void putprompt(const char *s) {
-    cmdedit_prompt = s;
+       if (subtype == VSPLUS || subtype == VSLENGTH)
+               STADJUST(-len, expdest);
+       return len;
 }
-#else
-static inline void putprompt(const char *s) {
-    out2str(s);
-}
-#endif
-
-#define EOF_NLEFT -99           /* value of parsenleft when EOF pushed back */
-
 
 
 /*
- * Same as pgetc(), but ignores PEOA.
+ * Record the fact that we have to scan this region of the
+ * string for IFS characters.
  */
 
-#ifdef CONFIG_ASH_ALIAS
-static int
-pgetc2(void)
+static void
+recordregion(int start, int end, int nulonly)
 {
-       int c;
-       do {
-               c = pgetc_macro();
-       } while (c == PEOA);
-       return c;
+       struct ifsregion *ifsp;
+
+       if (ifslastp == NULL) {
+               ifsp = &ifsfirst;
+       } else {
+               INTOFF;
+               ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion));
+               ifsp->next = NULL;
+               ifslastp->next = ifsp;
+               INTON;
+       }
+       ifslastp = ifsp;
+       ifslastp->begoff = start;
+       ifslastp->endoff = end;
+       ifslastp->nulonly = nulonly;
 }
-#else
-static inline int pgetc2(void) { return pgetc_macro(); }
-#endif
+
 
 /*
- * Read a line from the script.
+ * Break the argument string into pieces based upon IFS and add the
+ * strings to the argument list.  The regions of the string to be
+ * searched for IFS characters have been stored by recordregion.
  */
-
-static inline char *
-pfgets(char *line, int len)
+static void
+ifsbreakup(char *string, struct arglist *arglist)
 {
-       char *p = line;
-       int nleft = len;
-       int c;
-
-       while (--nleft > 0) {
-               c = pgetc2();
-               if (c == PEOF) {
-                       if (p == line)
-                               return NULL;
-                       break;
-               }
-               *p++ = c;
-               if (c == '\n')
-                       break;
-       }
-       *p = '\0';
-       return line;
-}
-
-static inline int
-preadfd(void)
-{
-    int nr;
-    char *buf =  parsefile->buf;
-    parsenextc = buf;
+       struct ifsregion *ifsp;
+       struct strlist *sp;
+       char *start;
+       char *p;
+       char *q;
+       const char *ifs, *realifs;
+       int ifsspc;
+       int nulonly;
 
-retry:
-#ifdef CONFIG_FEATURE_COMMAND_EDITING
-       {
-           if (!iflag || parsefile->fd)
-                   nr = safe_read(parsefile->fd, buf, BUFSIZ - 1);
-           else {
-                   nr = cmdedit_read_input((char*)cmdedit_prompt, buf);
-           }
-       }
-#else
-       nr = safe_read(parsefile->fd, buf, BUFSIZ - 1);
-#endif
 
-       if (nr < 0) {
-               if (parsefile->fd == 0 && errno == EWOULDBLOCK) {
-                       int flags = fcntl(0, F_GETFL, 0);
-                       if (flags >= 0 && flags & O_NONBLOCK) {
-                               flags &=~ O_NONBLOCK;
-                               if (fcntl(0, F_SETFL, flags) >= 0) {
-                                       out2str("sh: turning off NDELAY mode\n");
-                                       goto retry;
-                               }
+       start = string;
+       if (ifslastp != NULL) {
+               ifsspc = 0;
+               nulonly = 0;
+               realifs = ifsset() ? ifsval() : defifs;
+               ifsp = &ifsfirst;
+               do {
+                       p = string + ifsp->begoff;
+                       nulonly = ifsp->nulonly;
+                       ifs = nulonly ? nullstr : realifs;
+                       ifsspc = 0;
+                       while (p < string + ifsp->endoff) {
+                               q = p;
+                               if (*p == CTLESC)
+                                       p++;
+                               if (strchr(ifs, *p)) {
+                                       if (!nulonly)
+                                               ifsspc = (strchr(defifs, *p) != NULL);
+                                       /* Ignore IFS whitespace at start */
+                                       if (q == start && ifsspc) {
+                                               p++;
+                                               start = p;
+                                               continue;
+                                       }
+                                       *q = '\0';
+                                       sp = (struct strlist *)stalloc(sizeof *sp);
+                                       sp->text = start;
+                                       *arglist->lastp = sp;
+                                       arglist->lastp = &sp->next;
+                                       p++;
+                                       if (!nulonly) {
+                                               for (;;) {
+                                                       if (p >= string + ifsp->endoff) {
+                                                               break;
+                                                       }
+                                                       q = p;
+                                                       if (*p == CTLESC)
+                                                               p++;
+                                                       if (strchr(ifs, *p) == NULL ) {
+                                                               p = q;
+                                                               break;
+                                                       } else if (strchr(defifs, *p) == NULL) {
+                                                               if (ifsspc) {
+                                                                       p++;
+                                                                       ifsspc = 0;
+                                                               } else {
+                                                                       p = q;
+                                                                       break;
+                                                               }
+                                                       } else
+                                                               p++;
+                                               }
+                                       }
+                                       start = p;
+                               } else
+                                       p++;
                        }
-               }
+               } while ((ifsp = ifsp->next) != NULL);
+               if (nulonly)
+                       goto add;
        }
-       return nr;
+
+       if (!*start)
+               return;
+
+add:
+       sp = (struct strlist *)stalloc(sizeof *sp);
+       sp->text = start;
+       *arglist->lastp = sp;
+       arglist->lastp = &sp->next;
 }
 
 static void
-popstring(void)
+ifsfree(void)
 {
-       struct strpush *sp = parsefile->strpush;
+       struct ifsregion *p;
 
        INTOFF;
-#ifdef CONFIG_ASH_ALIAS
-       if (sp->ap) {
-               if (parsenextc[-1] == ' ' || parsenextc[-1] == '\t') {
-                       if (!checkalias) {
-                               checkalias = 1;
-                       }
-               }
-               if (sp->string != sp->ap->val) {
-                       ckfree(sp->string);
-               }
-
-               sp->ap->flag &= ~ALIASINUSE;
-               if (sp->ap->flag & ALIASDEAD) {
-                       unalias(sp->ap->name);
-               }
-       }
-#endif
-       parsenextc = sp->prevstring;
-       parsenleft = sp->prevnleft;
-/*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/
-       parsefile->strpush = sp->prev;
-       if (sp != &(parsefile->basestrpush))
-               ckfree(sp);
+       p = ifsfirst.next;
+       do {
+               struct ifsregion *ifsp;
+               ifsp = p->next;
+               ckfree(p);
+               p = ifsp;
+       } while (p);
+       ifslastp = NULL;
+       ifsfirst.next = NULL;
        INTON;
 }
 
+static void expmeta(char *, char *);
+static struct strlist *expsort(struct strlist *);
+static struct strlist *msort(struct strlist *, int);
 
-/*
- * Refill the input buffer and return the next input character:
- *
- * 1) If a string was pushed back on the input, pop it;
- * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading
- *    from a string so we can't refill the buffer, return EOF.
- * 3) If the is more stuff in this buffer, use it else call read to fill it.
- * 4) Process input up to the next newline, deleting nul characters.
- */
-
-static int
-preadbuffer(void)
-{
-       char *p, *q;
-       int more;
-       char savec;
-
-       while (parsefile->strpush) {
-#ifdef CONFIG_ASH_ALIAS
-               if (parsenleft == -1 && parsefile->strpush->ap &&
-                       parsenextc[-1] != ' ' && parsenextc[-1] != '\t') {
-                       return PEOA;
-               }
-#endif
-               popstring();
-               if (--parsenleft >= 0)
-                       return (*parsenextc++);
-       }
-       if (parsenleft == EOF_NLEFT || parsefile->buf == NULL)
-               return PEOF;
-       flushall();
+static char *expdir;
 
-again:
-       if (parselleft <= 0) {
-               if ((parselleft = preadfd()) <= 0) {
-                       parselleft = parsenleft = EOF_NLEFT;
-                       return PEOF;
-               }
-       }
 
-       q = p = parsenextc;
+static void
+expandmeta(struct strlist *str, int flag)
+{
+       static const char metachars[] = {
+               '*', '?', '[', 0
+       };
+       /* TODO - EXP_REDIR */
 
-       /* delete nul characters */
-       for (more = 1; more;) {
-               switch (*p) {
-               case '\0':
-                       p++;    /* Skip nul */
-                       goto check;
+       while (str) {
+               struct strlist **savelastp;
+               struct strlist *sp;
+               char *p;
 
+               if (fflag)
+                       goto nometa;
+               if (!strpbrk(str->text, metachars))
+                       goto nometa;
+               savelastp = exparg.lastp;
 
-               case '\n':
-                       parsenleft = q - parsenextc;
-                       more = 0; /* Stop processing here */
-                       break;
+               INTOFF;
+               p = preglob(str->text, 0, RMESCAPE_ALLOC | RMESCAPE_HEAP);
+               {
+                       int i = strlen(str->text);
+                       expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */
                }
 
-               *q++ = *p++;
-check:
-               if (--parselleft <= 0 && more) {
-                       parsenleft = q - parsenextc - 1;
-                       if (parsenleft < 0)
-                               goto again;
-                       more = 0;
+               expmeta(expdir, p);
+               ckfree(expdir);
+               if (p != str->text)
+                       ckfree(p);
+               INTON;
+               if (exparg.lastp == savelastp) {
+                       /*
+                        * no matches
+                        */
+nometa:
+                       *exparg.lastp = str;
+                       rmescapes(str->text);
+                       exparg.lastp = &str->next;
+               } else {
+                       *exparg.lastp = NULL;
+                       *savelastp = sp = expsort(*savelastp);
+                       while (sp->next != NULL)
+                               sp = sp->next;
+                       exparg.lastp = &sp->next;
                }
+               str = str->next;
        }
+}
 
-       savec = *q;
-       *q = '\0';
-
-       if (vflag) {
-               out2str(parsenextc);
-       }
+/*
+ * Add a file name to the list.
+ */
 
-       *q = savec;
+static void
+addfname(const char *name)
+{
+       struct strlist *sp;
 
-       return *parsenextc++;
+       sp = (struct strlist *)stalloc(sizeof *sp);
+       sp->text = sstrdup(name);
+       *exparg.lastp = sp;
+       exparg.lastp = &sp->next;
 }
 
 
 /*
- * Push a string back onto the input at this current parsefile level.
- * We handle aliases this way.
+ * Do metacharacter (i.e. *, ?, [...]) expansion.
  */
+
 static void
-pushstring(char *s, int len, void *ap)
+expmeta(char *enddir, char *name)
 {
-       struct strpush *sp;
+       char *p;
+       const char *cp;
+       char *start;
+       char *endname;
+       int metaflag;
+       struct stat statb;
+       DIR *dirp;
+       struct dirent *dp;
+       int atend;
+       int matchdot;
 
-       INTOFF;
-/*dprintf("*** calling pushstring: %s, %d\n", s, len);*/
-       if (parsefile->strpush) {
-               sp = xmalloc(sizeof (struct strpush));
-               sp->prev = parsefile->strpush;
-               parsefile->strpush = sp;
-       } else
-               sp = parsefile->strpush = &(parsefile->basestrpush);
-       sp->prevstring = parsenextc;
-       sp->prevnleft = parsenleft;
-#ifdef CONFIG_ASH_ALIAS
-       sp->ap = (struct alias *)ap;
-       if (ap) {
-               ((struct alias *)ap)->flag |= ALIASINUSE;
-               sp->string = s;
+       metaflag = 0;
+       start = name;
+       for (p = name; *p; p++) {
+               if (*p == '*' || *p == '?')
+                       metaflag = 1;
+               else if (*p == '[') {
+                       char *q = p + 1;
+                       if (*q == '!')
+                               q++;
+                       for (;;) {
+                               if (*q == '\\')
+                                       q++;
+                               if (*q == '/' || *q == '\0')
+                                       break;
+                               if (*++q == ']') {
+                                       metaflag = 1;
+                                       break;
+                               }
+                       }
+               } else if (*p == '\\')
+                       p++;
+               else if (*p == '/') {
+                       if (metaflag)
+                               goto out;
+                       start = p + 1;
+               }
        }
-#endif
-       parsenextc = s;
-       parsenleft = len;
-       INTON;
+out:
+       if (metaflag == 0) {    /* we've reached the end of the file name */
+               if (enddir != expdir)
+                       metaflag++;
+               p = name;
+               do {
+                       if (*p == '\\')
+                               p++;
+                       *enddir++ = *p;
+               } while (*p++);
+               if (metaflag == 0 || lstat(expdir, &statb) >= 0)
+                       addfname(expdir);
+               return;
+       }
+       endname = p;
+       if (name < start) {
+               p = name;
+               do {
+                       if (*p == '\\')
+                               p++;
+                       *enddir++ = *p++;
+               } while (p < start);
+       }
+       if (enddir == expdir) {
+               cp = ".";
+       } else if (enddir == expdir + 1 && *expdir == '/') {
+               cp = "/";
+       } else {
+               cp = expdir;
+               enddir[-1] = '\0';
+       }
+       if ((dirp = opendir(cp)) == NULL)
+               return;
+       if (enddir != expdir)
+               enddir[-1] = '/';
+       if (*endname == 0) {
+               atend = 1;
+       } else {
+               atend = 0;
+               *endname++ = '\0';
+       }
+       matchdot = 0;
+       p = start;
+       if (*p == '\\')
+               p++;
+       if (*p == '.')
+               matchdot++;
+       while (! intpending && (dp = readdir(dirp)) != NULL) {
+               if (dp->d_name[0] == '.' && ! matchdot)
+                       continue;
+               if (pmatch(start, dp->d_name)) {
+                       if (atend) {
+                               scopy(dp->d_name, enddir);
+                               addfname(expdir);
+                       } else {
+                               for (p = enddir, cp = dp->d_name;
+                                    (*p++ = *cp++) != '\0';)
+                                       continue;
+                               p[-1] = '/';
+                               expmeta(p, endname);
+                       }
+               }
+       }
+       closedir(dirp);
+       if (! atend)
+               endname[-1] = '/';
 }
 
-
 /*
- * Like setinputfile, but takes input from a string.
+ * Sort the results of file name expansion.  It calculates the number of
+ * strings to sort and then calls msort (short for merge sort) to do the
+ * work.
  */
 
-static void
-setinputstring(char *string)
+static struct strlist *
+expsort(struct strlist *str)
 {
-       INTOFF;
-       pushfile();
-       parsenextc = string;
-       parsenleft = strlen(string);
-       parsefile->buf = NULL;
-       plinno = 1;
-       INTON;
-}
-
+       int len;
+       struct strlist *sp;
 
+       len = 0;
+       for (sp = str ; sp ; sp = sp->next)
+               len++;
+       return msort(str, len);
+}
 
-/*
- * To handle the "." command, a stack of input files is used.  Pushfile
- * adds a new entry to the stack and popfile restores the previous level.
- */
 
-static void
-pushfile(void)
+static struct strlist *
+msort(struct strlist *list, int len)
 {
-       struct parsefile *pf;
-
-       parsefile->nleft = parsenleft;
-       parsefile->lleft = parselleft;
-       parsefile->nextc = parsenextc;
-       parsefile->linno = plinno;
-       pf = (struct parsefile *)xmalloc(sizeof (struct parsefile));
-       pf->prev = parsefile;
-       pf->fd = -1;
-       pf->strpush = NULL;
-       pf->basestrpush.prev = NULL;
-       parsefile = pf;
-}
+       struct strlist *p, *q = NULL;
+       struct strlist **lpp;
+       int half;
+       int n;
 
-#ifdef CONFIG_ASH_JOB_CONTROL
-static void restartjob (struct job *);
+       if (len <= 1)
+               return list;
+       half = len >> 1;
+       p = list;
+       for (n = half ; --n >= 0 ; ) {
+               q = p;
+               p = p->next;
+       }
+       q->next = NULL;                 /* terminate first half of list */
+       q = msort(list, half);          /* sort first half of list */
+       p = msort(p, len - half);               /* sort second half */
+       lpp = &list;
+       for (;;) {
+#ifdef CONFIG_LOCALE_SUPPORT
+               if (strcoll(p->text, q->text) < 0)
+#else
+               if (strcmp(p->text, q->text) < 0)
 #endif
-static void freejob (struct job *);
-static struct job *getjob (const char *);
-static int dowait (int, struct job *);
-static void waitonint(int);
+                                               {
+                       *lpp = p;
+                       lpp = &p->next;
+                       if ((p = *lpp) == NULL) {
+                               *lpp = q;
+                               break;
+                       }
+               } else {
+                       *lpp = q;
+                       lpp = &q->next;
+                       if ((q = *lpp) == NULL) {
+                               *lpp = p;
+                               break;
+                       }
+               }
+       }
+       return list;
+}
 
 
 /*
- * We keep track of whether or not fd0 has been redirected.  This is for
- * background commands, where we want to redirect fd0 to /dev/null only
- * if it hasn't already been redirected.
-*/
-static int fd0_redirected = 0;
+ * Returns true if the pattern matches the string.
+ */
 
-/* Return true if fd 0 has already been redirected at least once.  */
 static inline int
-fd0_redirected_p (void) 
+patmatch(char *pattern, const char *string)
 {
-       return fd0_redirected != 0;
+       return pmatch(preglob(pattern, 0, 0), string);
 }
 
-static void dupredirect (const union node *, int, int fd1dup);
 
-#ifdef CONFIG_ASH_JOB_CONTROL
 /*
- * Turn job control on and off.
- *
- * Note:  This code assumes that the third arg to ioctl is a character
- * pointer, which is true on Berkeley systems but not System V.  Since
- * System V doesn't have job control yet, this isn't a problem now.
+ * Remove any CTLESC characters from a string.
  */
 
-
-
-static void setjobctl(int enable)
+static char *
+_rmescapes(char *str, int flag)
 {
-#ifdef OLD_TTY_DRIVER
-       int ldisc;
-#endif
+       char *p, *q, *r;
+       static const char qchars[] = { CTLESC, CTLQUOTEMARK, 0 };
+       unsigned inquotes;
+       int notescaped;
+       int globbing;
 
-       if (enable == jobctl || rootshell == 0)
-               return;
-       if (enable) {
-               do { /* while we are in the background */
-#ifdef OLD_TTY_DRIVER
-                       if (ioctl(2, TIOCGPGRP, (char *)&initialpgrp) < 0) {
-#else
-                       initialpgrp = tcgetpgrp(2);
-                       if (initialpgrp < 0) {
-#endif
-                               out2str("sh: can't access tty; job control turned off\n");
-                               mflag = 0;
-                               return;
-                       }
-                       if (initialpgrp == -1)
-                               initialpgrp = getpgrp();
-                       else if (initialpgrp != getpgrp()) {
-                               killpg(initialpgrp, SIGTTIN);
-                               continue;
+       p = strpbrk(str, qchars);
+       if (!p) {
+               return str;
+       }
+       q = p;
+       r = str;
+       if (flag & RMESCAPE_ALLOC) {
+               size_t len = p - str;
+               size_t fulllen = len + strlen(p) + 1;
+
+               if (flag & RMESCAPE_GROW) {
+                       r = makestrspace(fulllen, expdest);
+               } else if (flag & RMESCAPE_HEAP) {
+                       r = ckmalloc(fulllen);
+               } else {
+                       r = stalloc(fulllen);
+               }
+               q = r;
+               if (len > 0) {
+                       q = mempcpy(q, str, len);
+               }
+       }
+       inquotes = (flag & RMESCAPE_QUOTED) ^ RMESCAPE_QUOTED;
+       globbing = flag & RMESCAPE_GLOB;
+       notescaped = globbing;
+       while (*p) {
+               if (*p == CTLQUOTEMARK) {
+                       inquotes = ~inquotes;
+                       p++;
+                       notescaped = globbing;
+                       continue;
+               }
+               if (*p == '\\') {
+                       /* naked back slash */
+                       notescaped = 0;
+                       goto copy;
+               }
+               if (*p == CTLESC) {
+                       p++;
+                       if (notescaped && inquotes && *p != '/') {
+                               *q++ = '\\';
                        }
-               } while (0);
-#ifdef OLD_TTY_DRIVER
-               if (ioctl(2, TIOCGETD, (char *)&ldisc) < 0 || ldisc != NTTYDISC) {
-                       out2str("sh: need new tty driver to run job control; job control turned off\n");
-                       mflag = 0;
-                       return;
                }
-#endif
-               setsignal(SIGTSTP);
-               setsignal(SIGTTOU);
-               setsignal(SIGTTIN);
-               setpgid(0, rootpid);
-#ifdef OLD_TTY_DRIVER
-               ioctl(2, TIOCSPGRP, (char *)&rootpid);
-#else
-               tcsetpgrp(2, rootpid);
-#endif
-       } else { /* turning job control off */
-               setpgid(0, initialpgrp);
-#ifdef OLD_TTY_DRIVER
-               ioctl(2, TIOCSPGRP, (char *)&initialpgrp);
-#else
-               tcsetpgrp(2, initialpgrp);
-#endif
-               setsignal(SIGTSTP);
-               setsignal(SIGTTOU);
-               setsignal(SIGTTIN);
+               notescaped = globbing;
+copy:
+               *q++ = *p++;
+       }
+       *q = '\0';
+       if (flag & RMESCAPE_GROW) {
+               expdest = r;
+               STADJUST(q - r + 1, expdest);
        }
-       jobctl = enable;
+       return r;
 }
-#endif
 
 
-#ifdef CONFIG_ASH_JOB_CONTROL
-static int
-killcmd(int argc, char **argv)
+/*
+ * See if a pattern matches in a case statement.
+ */
+
+int
+casematch(union node *pattern, char *val)
 {
-       int signo = -1;
-       int list = 0;
-       int i;
-       pid_t pid;
-       struct job *jp;
+       struct stackmark smark;
+       int result;
 
-       if (argc <= 1) {
-usage:
-               error(
-"Usage: kill [-s sigspec | -signum | -sigspec] [pid | job]... or\n"
-"kill -l [exitstatus]"
-               );
-       }
+       setstackmark(&smark);
+       argbackq = pattern->narg.backquote;
+       STARTSTACKSTR(expdest);
+       ifslastp = NULL;
+       argstr(pattern->narg.text, EXP_TILDE | EXP_CASE);
+       STACKSTRNUL(expdest);
+       result = patmatch(stackblock(), val);
+       popstackmark(&smark);
+       return result;
+}
 
-       if (*argv[1] == '-') {
-               signo = decode_signal(argv[1] + 1, 1);
-               if (signo < 0) {
-                       int c;
+/*
+ * Our own itoa().
+ */
 
-                       while ((c = nextopt("ls:")) != '\0')
-                               switch (c) {
-                               case 'l':
-                                       list = 1;
-                                       break;
-                               case 's':
-                                       signo = decode_signal(optionarg, 1);
-                                       if (signo < 0) {
-                                               error(
-                                                       "invalid signal number or name: %s",
-                                                       optionarg
-                                               );
-                                       }
-                                       break;
-#ifdef DEBUG
-                               default:
-                                       error(
-       "nextopt returned character code 0%o", c);
+static int
+cvtnum(arith_t num)
+{
+       int len;
+
+       expdest = makestrspace(32, expdest);
+#ifdef CONFIG_ASH_MATH_SUPPORT_64
+       len = fmtstr(expdest, 32, "%lld", (long long) num);
+#else
+       len = fmtstr(expdest, 32, "%ld", num);
 #endif
-                       }
-               } else
-                       argptr++;
-       }
+       STADJUST(len, expdest);
+       return len;
+}
 
-       if (!list && signo < 0)
-               signo = SIGTERM;
+static void
+varunset(const char *end, const char *var, const char *umsg, int varflags)
+{
+       const char *msg;
+       const char *tail;
 
-       if ((signo < 0 || !*argptr) ^ list) {
-               goto usage;
+       tail = nullstr;
+       msg = "parameter not set";
+       if (umsg) {
+               if (*end == CTLENDVAR) {
+                       if (varflags & VSNUL)
+                               tail = " or null";
+               } else
+                       msg = umsg;
        }
+       sh_error("%.*s: %s%s", end - var - 1, var, msg, tail);
+}
 
-       if (list) {
-               const char *name;
 
-               if (!*argptr) {
-                       out1str("0\n");
-                       for (i = 1; i < NSIG; i++) {
-                               name = u_signal_names(0, &i, 1);
-                               if(name)
-                                       puts(name);
-                       }
-                       return 0;
-               }
-               name = u_signal_names(*argptr, &signo, -1);
-               if (name)
-                       puts(name);
-               else
-                       error("invalid signal number or exit status: %s",
-                             *argptr);
-               return 0;
-       }
+/*      input.c      */
 
-       do {
-               if (**argptr == '%') {
-                       jp = getjob(*argptr);
-                       if (jp->jobctl == 0)
-                               error("job %s not created under job control",
-                                     *argptr);
-                       pid = -jp->ps[0].pid;
-               } else
-                       pid = atoi(*argptr);
-               if (kill(pid, signo) != 0)
-                       error("%s: %m", *argptr);
-       } while (*++argptr);
+/*
+ * This implements the input routines used by the parser.
+ */
 
-       return 0;
-}
+#define EOF_NLEFT -99           /* value of parsenleft when EOF pushed back */
 
-static int
-fgcmd(int argc, char **argv)
-{
-       struct job *jp;
-       int pgrp;
-       int status;
+static void pushfile(void);
 
-       jp = getjob(argv[1]);
-       if (jp->jobctl == 0)
-               error("job not created under job control");
-       pgrp = jp->ps[0].pid;
-#ifdef OLD_TTY_DRIVER
-       ioctl(2, TIOCSPGRP, (char *)&pgrp);
-#else
-       tcsetpgrp(2, pgrp);
-#endif
-       restartjob(jp);
-       status = waitforjob(jp);
-       return status;
-}
+/*
+ * Read a character from the script, returning PEOF on end of file.
+ * Nul characters in the input are silently discarded.
+ */
 
 
+#define pgetc_as_macro()   (--parsenleft >= 0? SC2INT(*parsenextc++) : preadbuffer())
+
+#ifdef CONFIG_ASH_OPTIMIZE_FOR_SIZE
+#define pgetc_macro() pgetc()
 static int
-bgcmd(int argc, char **argv)
+pgetc(void)
 {
-       struct job *jp;
-
-       do {
-               jp = getjob(*++argv);
-               if (jp->jobctl == 0)
-                       error("job not created under job control");
-               restartjob(jp);
-       } while (--argc > 1);
-       return 0;
+       return pgetc_as_macro();
 }
-
-
-static void
-restartjob(struct job *jp)
+#else
+#define pgetc_macro()   pgetc_as_macro()
+static int
+pgetc(void)
 {
-       struct procstat *ps;
-       int i;
-
-       if (jp->state == JOBDONE)
-               return;
-       INTOFF;
-       killpg(jp->ps[0].pid, SIGCONT);
-       for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) {
-               if (WIFSTOPPED(ps->status)) {
-                       ps->status = -1;
-                       jp->state = 0;
-               }
-       }
-       INTON;
+       return pgetc_macro();
 }
 #endif
 
-static void showjobs(int change);
 
+/*
+ * Same as pgetc(), but ignores PEOA.
+ */
+#ifdef CONFIG_ASH_ALIAS
+static int pgetc2(void)
+{
+       int c;
 
-static int
-jobscmd(int argc, char **argv)
+       do {
+               c = pgetc_macro();
+       } while (c == PEOA);
+       return c;
+}
+#else
+static inline int pgetc2(void)
 {
-       showjobs(0);
-       return 0;
+       return pgetc_macro();
 }
-
+#endif
 
 /*
- * Print a list of jobs.  If "change" is nonzero, only print jobs whose
- * statuses have changed since the last call to showjobs.
- *
- * If the shell is interrupted in the process of creating a job, the
- * result may be a job structure containing zero processes.  Such structures
- * will be freed here.
+ * Read a line from the script.
  */
 
-static void
-showjobs(int change)
+static inline char *
+pfgets(char *line, int len)
 {
-       int jobno;
-       int procno;
-       int i;
-       struct job *jp;
-       struct procstat *ps;
-       int col;
-       char s[64];
+       char *p = line;
+       int nleft = len;
+       int c;
 
-       TRACE(("showjobs(%d) called\n", change));
-       while (dowait(0, (struct job *)NULL) > 0);
-       for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) {
-               if (! jp->used)
-                       continue;
-               if (jp->nprocs == 0) {
-                       freejob(jp);
-                       continue;
-               }
-               if (change && ! jp->changed)
-                       continue;
-               procno = jp->nprocs;
-               for (ps = jp->ps ; ; ps++) {    /* for each process */
-                       if (ps == jp->ps)
-                               snprintf(s, 64, "[%d] %ld ", jobno,
-                                   (long)ps->pid);
-                       else
-                               snprintf(s, 64, "    %ld ",
-                                   (long)ps->pid);
-                       out1str(s);
-                       col = strlen(s);
-                       s[0] = '\0';
-                       if (ps->status == -1) {
-                               /* don't print anything */
-                       } else if (WIFEXITED(ps->status)) {
-                               snprintf(s, 64, "Exit %d",
-                                      WEXITSTATUS(ps->status));
-                       } else {
-#ifdef CONFIG_ASH_JOB_CONTROL
-                               if (WIFSTOPPED(ps->status))
-                                       i = WSTOPSIG(ps->status);
-                               else /* WIFSIGNALED(ps->status) */
-#endif
-                                       i = WTERMSIG(ps->status);
-                               if ((i & 0x7F) < NSIG && sys_siglist[i & 0x7F])
-                                       strcpy(s, sys_siglist[i & 0x7F]);
-                               else
-                                       snprintf(s, 64, "Signal %d", i & 0x7F);
-                               if (WCOREDUMP(ps->status))
-                                       strcat(s, " (core dumped)");
-                       }
-                       out1str(s);
-                       col += strlen(s);
-                       printf(
-                               "%*c%s\n", 30 - col >= 0 ? 30 - col : 0, ' ',
-                               ps->cmd
-                       );
-                       if (--procno <= 0)
-                               break;
-               }
-               jp->changed = 0;
-               if (jp->state == JOBDONE) {
-                       freejob(jp);
+       while (--nleft > 0) {
+               c = pgetc2();
+               if (c == PEOF) {
+                       if (p == line)
+                               return NULL;
+                       break;
                }
+               *p++ = c;
+               if (c == '\n')
+                       break;
        }
+       *p = '\0';
+       return line;
 }
 
 
-/*
- * Mark a job structure as unused.
- */
 
-static void
-freejob(struct job *jp)
+#ifdef CONFIG_FEATURE_COMMAND_EDITING
+#ifdef CONFIG_ASH_EXPAND_PRMT
+static char *cmdedit_prompt;
+#else
+static const char *cmdedit_prompt;
+#endif
+static inline void putprompt(const char *s)
 {
-       const struct procstat *ps;
-       int i;
-
-       INTOFF;
-       for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) {
-               if (ps->cmd != nullstr)
-                       ckfree(ps->cmd);
-       }
-       if (jp->ps != &jp->ps0)
-               ckfree(jp->ps);
-       jp->used = 0;
-#ifdef CONFIG_ASH_JOB_CONTROL
-       if (curjob == jp - jobtab + 1)
-               curjob = 0;
+#ifdef CONFIG_ASH_EXPAND_PRMT
+       free(cmdedit_prompt);
+       cmdedit_prompt = xstrdup(s);
+#else
+       cmdedit_prompt = s;
 #endif
-       INTON;
 }
+#else
+static inline void putprompt(const char *s)
+{
+       out2str(s);
+}
+#endif
 
-
-
-static int
-waitcmd(int argc, char **argv)
+static inline int
+preadfd(void)
 {
-       struct job *job;
-       int status, retval;
-       struct job *jp;
+       int nr;
+       char *buf =  parsefile->buf;
+       parsenextc = buf;
 
-       if (--argc > 0) {
-start:
-               job = getjob(*++argv);
-       } else {
-               job = NULL;
-       }
-       for (;;) {      /* loop until process terminated or stopped */
-               if (job != NULL) {
-                       if (job->state) {
-                               status = job->ps[job->nprocs - 1].status;
-                               if (! iflag)
-                                       freejob(job);
-                               if (--argc) {
-                                       goto start;
-                               }
-                               if (WIFEXITED(status))
-                                       retval = WEXITSTATUS(status);
-#ifdef CONFIG_ASH_JOB_CONTROL
-                               else if (WIFSTOPPED(status))
-                                       retval = WSTOPSIG(status) + 128;
-#endif
-                               else {
-                                       /* XXX: limits number of signals */
-                                       retval = WTERMSIG(status) + 128;
-                               }
-                               return retval;
-                       }
-               } else {
-                       for (jp = jobtab ; ; jp++) {
-                               if (jp >= jobtab + njobs) {     /* no running procs */
-                                       return 0;
-                               }
-                               if (jp->used && jp->state == 0)
-                                       break;
+retry:
+#ifdef CONFIG_FEATURE_COMMAND_EDITING
+       if (!iflag || parsefile->fd)
+               nr = safe_read(parsefile->fd, buf, BUFSIZ - 1);
+       else {
+#ifdef CONFIG_FEATURE_COMMAND_TAB_COMPLETION
+               cmdedit_path_lookup = pathval();
+#endif
+               nr = cmdedit_read_input((char *) cmdedit_prompt, buf);
+               if(nr == 0) {
+                       /* Ctrl+C presend */
+                       if(trap[SIGINT]) {
+                               buf[0] = '\n';
+                               buf[1] = 0;
+                               raise(SIGINT);
+                               return 1;
                        }
+                       goto retry;
                }
-               if (dowait(2, 0) < 0 && errno == EINTR) {
-                       return 129;
+               if(nr < 0 && errno == 0) {
+                       /* Ctrl+D presend */
+                       nr = 0;
                }
        }
-}
-
-
-
-/*
- * Convert a job name to a job structure.
- */
-
-static struct job *
-getjob(const char *name)
-{
-       int jobno;
-       struct job *jp;
-       int pid;
-       int i;
-
-       if (name == NULL) {
-#ifdef CONFIG_ASH_JOB_CONTROL
-currentjob:
-               if ((jobno = curjob) == 0 || jobtab[jobno - 1].used == 0)
-                       error("No current job");
-               return &jobtab[jobno - 1];
 #else
-               error("No current job");
-#endif
-       } else if (name[0] == '%') {
-               if (is_digit(name[1])) {
-                       jobno = number(name + 1);
-                       if (jobno > 0 && jobno <= njobs
-                        && jobtab[jobno - 1].used != 0)
-                               return &jobtab[jobno - 1];
-#ifdef CONFIG_ASH_JOB_CONTROL
-               } else if (name[1] == '%' && name[2] == '\0') {
-                       goto currentjob;
+       nr = safe_read(parsefile->fd, buf, BUFSIZ - 1);
 #endif
-               } else {
-                       struct job *found = NULL;
-                       for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
-                               if (jp->used && jp->nprocs > 0
-                                && prefix(name + 1, jp->ps[0].cmd)) {
-                                       if (found)
-                                               error("%s: ambiguous", name);
-                                       found = jp;
+
+       if (nr < 0) {
+               if (parsefile->fd == 0 && errno == EWOULDBLOCK) {
+                       int flags = fcntl(0, F_GETFL, 0);
+                       if (flags >= 0 && flags & O_NONBLOCK) {
+                               flags &=~ O_NONBLOCK;
+                               if (fcntl(0, F_SETFL, flags) >= 0) {
+                                       out2str("sh: turning off NDELAY mode\n");
+                                       goto retry;
                                }
                        }
-                       if (found)
-                               return found;
-               }
-       } else if (is_number(name, &pid)) {
-               for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
-                       if (jp->used && jp->nprocs > 0
-                        && jp->ps[jp->nprocs - 1].pid == pid)
-                               return jp;
                }
        }
-       error("No such job: %s", name);
-       /* NOTREACHED */
+       return nr;
 }
 
-
-
 /*
- * Return a new job structure,
+ * Refill the input buffer and return the next input character:
+ *
+ * 1) If a string was pushed back on the input, pop it;
+ * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading
+ *    from a string so we can't refill the buffer, return EOF.
+ * 3) If the is more stuff in this buffer, use it else call read to fill it.
+ * 4) Process input up to the next newline, deleting nul characters.
  */
 
-static struct job *
-makejob(const union node *node, int nprocs)
+int
+preadbuffer(void)
 {
-       int i;
-       struct job *jp;
-
-       for (i = njobs, jp = jobtab ; ; jp++) {
-               if (--i < 0) {
-                       INTOFF;
-                       if (njobs == 0) {
-                               jobtab = xmalloc(4 * sizeof jobtab[0]);
-                       } else {
-                               jp = xmalloc((njobs + 4) * sizeof jobtab[0]);
-                               memcpy(jp, jobtab, njobs * sizeof jp[0]);
-                               /* Relocate `ps' pointers */
-                               for (i = 0; i < njobs; i++)
-                                       if (jp[i].ps == &jobtab[i].ps0)
-                                               jp[i].ps = &jp[i].ps0;
-                               ckfree(jobtab);
-                               jobtab = jp;
+       char *q;
+       int more;
+       char savec;
+
+       while (parsefile->strpush) {
+#ifdef CONFIG_ASH_ALIAS
+               if (parsenleft == -1 && parsefile->strpush->ap &&
+                       parsenextc[-1] != ' ' && parsenextc[-1] != '\t') {
+                       return PEOA;
+               }
+#endif
+               popstring();
+               if (--parsenleft >= 0)
+                       return SC2INT(*parsenextc++);
+       }
+       if (parsenleft == EOF_NLEFT || parsefile->buf == NULL)
+               return PEOF;
+       flushall();
+
+       more = parselleft;
+       if (more <= 0) {
+again:
+               if ((more = preadfd()) <= 0) {
+                       parselleft = parsenleft = EOF_NLEFT;
+                       return PEOF;
+               }
+       }
+
+       q = parsenextc;
+
+       /* delete nul characters */
+       for (;;) {
+               int c;
+
+               more--;
+               c = *q;
+
+               if (!c)
+                       memmove(q, q + 1, more);
+               else {
+                       q++;
+                       if (c == '\n') {
+                               parsenleft = q - parsenextc - 1;
+                               break;
                        }
-                       jp = jobtab + njobs;
-                       for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0);
-                       INTON;
-                       break;
                }
-               if (jp->used == 0)
+
+               if (more <= 0) {
+                       parsenleft = q - parsenextc - 1;
+                       if (parsenleft < 0)
+                               goto again;
                        break;
+               }
        }
-       INTOFF;
-       jp->state = 0;
-       jp->used = 1;
-       jp->changed = 0;
-       jp->nprocs = 0;
-#ifdef CONFIG_ASH_JOB_CONTROL
-       jp->jobctl = jobctl;
-#endif
-       if (nprocs > 1) {
-               jp->ps = xmalloc(nprocs * sizeof (struct procstat));
-       } else {
-               jp->ps = &jp->ps0;
+       parselleft = more;
+
+       savec = *q;
+       *q = '\0';
+
+       if (vflag) {
+               out2str(parsenextc);
        }
-       INTON;
-       TRACE(("makejob(0x%lx, %d) returns %%%d\n", (long)node, nprocs,
-           jp - jobtab + 1));
-       return jp;
-}
 
+       *q = savec;
+
+       return SC2INT(*parsenextc++);
+}
 
 /*
- * Fork of a subshell.  If we are doing job control, give the subshell its
- * own process group.  Jp is a job structure that the job is to be added to.
- * N is the command that will be evaluated by the child.  Both jp and n may
- * be NULL.  The mode parameter can be one of the following:
- *      FORK_FG - Fork off a foreground process.
- *      FORK_BG - Fork off a background process.
- *      FORK_NOJOB - Like FORK_FG, but don't give the process its own
- *                   process group even if job control is on.
- *
- * When job control is turned off, background processes have their standard
- * input redirected to /dev/null (except for the second and later processes
- * in a pipeline).
+ * Undo the last call to pgetc.  Only one character may be pushed back.
+ * PEOF may be pushed back.
  */
 
+void
+pungetc(void)
+{
+       parsenleft++;
+       parsenextc--;
+}
 
-
-static int
-forkshell(struct job *jp, const union node *n, int mode)
+/*
+ * Push a string back onto the input at this current parsefile level.
+ * We handle aliases this way.
+ */
+void
+pushstring(char *s, void *ap)
 {
-       int pid;
-#ifdef CONFIG_ASH_JOB_CONTROL
-       int pgrp;
-#endif
-       const char *devnull = _PATH_DEVNULL;
-       const char *nullerr = "Can't open %s";
+       struct strpush *sp;
+       size_t len;
 
-       TRACE(("forkshell(%%%d, 0x%lx, %d) called\n", jp - jobtab, (long)n,
-           mode));
+       len = strlen(s);
        INTOFF;
-#if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
-       pid = fork();
-#else
-       pid = vfork();
-#endif
-       if (pid == -1) {
-               TRACE(("Fork failed, errno=%d\n", errno));
-               INTON;
-               error("Cannot fork");
+/*dprintf("*** calling pushstring: %s, %d\n", s, len);*/
+       if (parsefile->strpush) {
+               sp = ckmalloc(sizeof (struct strpush));
+               sp->prev = parsefile->strpush;
+               parsefile->strpush = sp;
+       } else
+               sp = parsefile->strpush = &(parsefile->basestrpush);
+       sp->prevstring = parsenextc;
+       sp->prevnleft = parsenleft;
+#ifdef CONFIG_ASH_ALIAS
+       sp->ap = (struct alias *)ap;
+       if (ap) {
+               ((struct alias *)ap)->flag |= ALIASINUSE;
+               sp->string = s;
        }
-       if (pid == 0) {
-               struct job *p;
-               int wasroot;
-               int i;
-
-               TRACE(("Child shell %d\n", getpid()));
-               wasroot = rootshell;
-               rootshell = 0;
-               closescript();
-               INTON;
-               clear_traps();
-#ifdef CONFIG_ASH_JOB_CONTROL
-               jobctl = 0;             /* do job control only in root shell */
-               if (wasroot && mode != FORK_NOJOB && mflag) {
-                       if (jp == NULL || jp->nprocs == 0)
-                               pgrp = getpid();
-                       else
-                               pgrp = jp->ps[0].pid;
-                       setpgid(0, pgrp);
-                       if (mode == FORK_FG) {
-                               /*** this causes superfluous TIOCSPGRPS ***/
-#ifdef OLD_TTY_DRIVER
-                               if (ioctl(2, TIOCSPGRP, (char *)&pgrp) < 0)
-                                       error("TIOCSPGRP failed, errno=%d", errno);
-#else
-                               if (tcsetpgrp(2, pgrp) < 0)
-                                       error("tcsetpgrp failed, errno=%d", errno);
-#endif
-                       }
-                       setsignal(SIGTSTP);
-                       setsignal(SIGTTOU);
-               } else if (mode == FORK_BG) {
-#else
-               if (mode == FORK_BG) {
 #endif
-                       ignoresig(SIGINT);
-                       ignoresig(SIGQUIT);
-                       if ((jp == NULL || jp->nprocs == 0) &&
-                           ! fd0_redirected_p ()) {
-                               close(0);
-                               if (open(devnull, O_RDONLY) != 0)
-                                       error(nullerr, devnull);
-                       }
+       parsenextc = s;
+       parsenleft = len;
+       INTON;
+}
+
+void
+popstring(void)
+{
+       struct strpush *sp = parsefile->strpush;
+
+       INTOFF;
+#ifdef CONFIG_ASH_ALIAS
+       if (sp->ap) {
+               if (parsenextc[-1] == ' ' || parsenextc[-1] == '\t') {
+                       checkkwd |= CHKALIAS;
                }
-               for (i = njobs, p = jobtab ; --i >= 0 ; p++)
-                       if (p->used)
-                               freejob(p);
-               if (wasroot && iflag) {
-                       setsignal(SIGINT);
-                       setsignal(SIGQUIT);
-                       setsignal(SIGTERM);
+               if (sp->string != sp->ap->val) {
+                       ckfree(sp->string);
+               }
+               sp->ap->flag &= ~ALIASINUSE;
+               if (sp->ap->flag & ALIASDEAD) {
+                       unalias(sp->ap->name);
                }
-               return pid;
-       }
-#ifdef CONFIG_ASH_JOB_CONTROL
-       if (rootshell && mode != FORK_NOJOB && mflag) {
-               if (jp == NULL || jp->nprocs == 0)
-                       pgrp = pid;
-               else
-                       pgrp = jp->ps[0].pid;
-               setpgid(pid, pgrp);
        }
 #endif
-       if (mode == FORK_BG)
-               backgndpid = pid;               /* set $! */
-       if (jp) {
-               struct procstat *ps = &jp->ps[jp->nprocs++];
-               ps->pid = pid;
-               ps->status = -1;
-               ps->cmd = nullstr;
-               if (iflag && rootshell && n)
-                       ps->cmd = commandtext(n);
-       }
+       parsenextc = sp->prevstring;
+       parsenleft = sp->prevnleft;
+/*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/
+       parsefile->strpush = sp->prev;
+       if (sp != &(parsefile->basestrpush))
+               ckfree(sp);
        INTON;
-       TRACE(("In parent shell:  child = %d\n", pid));
-       return pid;
 }
 
-
-
 /*
- * Wait for job to finish.
- *
- * Under job control we have the problem that while a child process is
- * running interrupts generated by the user are sent to the child but not
- * to the shell.  This means that an infinite loop started by an inter-
- * active user may be hard to kill.  With job control turned off, an
- * interactive user may place an interactive program inside a loop.  If
- * the interactive program catches interrupts, the user doesn't want
- * these interrupts to also abort the loop.  The approach we take here
- * is to have the shell ignore interrupt signals while waiting for a
- * forground process to terminate, and then send itself an interrupt
- * signal if the child process was terminated by an interrupt signal.
- * Unfortunately, some programs want to do a bit of cleanup and then
- * exit on interrupt; unless these processes terminate themselves by
- * sending a signal to themselves (instead of calling exit) they will
- * confuse this approach.
+ * Set the input to take input from a file.  If push is set, push the
+ * old input onto the stack first.
  */
 
 static int
-waitforjob(struct job *jp)
+setinputfile(const char *fname, int flags)
 {
-#ifdef CONFIG_ASH_JOB_CONTROL
-       int mypgrp = getpgrp();
-#endif
-       int status;
-       int st;
-       struct sigaction act, oact;
+       int fd;
+       int fd2;
 
        INTOFF;
-       intreceived = 0;
-#ifdef CONFIG_ASH_JOB_CONTROL
-       if (!jobctl) {
-#else
-       if (!iflag) {
-#endif
-               sigaction(SIGINT, 0, &act);
-               act.sa_handler = waitonint;
-               sigaction(SIGINT, &act, &oact);
-       }
-       TRACE(("waitforjob(%%%d) called\n", jp - jobtab + 1));
-       while (jp->state == 0) {
-               dowait(1, jp);
-       }
-#ifdef CONFIG_ASH_JOB_CONTROL
-       if (!jobctl) {
-#else
-       if (!iflag) {
-#endif
-               sigaction(SIGINT, &oact, 0);
-               if (intreceived) kill(getpid(), SIGINT);
-       }
-#ifdef CONFIG_ASH_JOB_CONTROL
-       if (jp->jobctl) {
-#ifdef OLD_TTY_DRIVER
-               if (ioctl(2, TIOCSPGRP, (char *)&mypgrp) < 0)
-                       error("TIOCSPGRP failed, errno=%d\n", errno);
-#else
-               if (tcsetpgrp(2, mypgrp) < 0)
-                       error("tcsetpgrp failed, errno=%d\n", errno);
-#endif
+       if ((fd = open(fname, O_RDONLY)) < 0) {
+               if (flags & INPUT_NOFILE_OK)
+                       goto out;
+               sh_error("Can't open %s", fname);
        }
-       if (jp->state == CONFIG_ASH_JOB_CONTROLTOPPED)
-               curjob = jp - jobtab + 1;
-#endif
-       status = jp->ps[jp->nprocs - 1].status;
-       /* convert to 8 bits */
-       if (WIFEXITED(status))
-               st = WEXITSTATUS(status);
-#ifdef CONFIG_ASH_JOB_CONTROL
-       else if (WIFSTOPPED(status))
-               st = WSTOPSIG(status) + 128;
-#endif
-       else
-               st = WTERMSIG(status) + 128;
-#ifdef CONFIG_ASH_JOB_CONTROL
-       if (jp->jobctl) {
-               /*
-                * This is truly gross.
-                * If we're doing job control, then we did a TIOCSPGRP which
-                * caused us (the shell) to no longer be in the controlling
-                * session -- so we wouldn't have seen any ^C/SIGINT.  So, we
-                * intuit from the subprocess exit status whether a SIGINT
-                * occured, and if so interrupt ourselves.  Yuck.  - mycroft
-                */
-               if (WIFSIGNALED(status) && WTERMSIG(status) == SIGINT)
-                       raise(SIGINT);
+       if (fd < 10) {
+               fd2 = copyfd(fd, 10);
+               close(fd);
+               if (fd2 < 0)
+                       sh_error("Out of file descriptors");
+               fd = fd2;
        }
-       if (jp->state == JOBDONE)
-
-#endif
-               freejob(jp);
+       setinputfd(fd, flags & INPUT_PUSH_FILE);
+out:
        INTON;
-       return st;
+       return fd;
 }
 
 
+/*
+ * Like setinputfile, but takes an open file descriptor.  Call this with
+ * interrupts off.
+ */
+
+static void
+setinputfd(int fd, int push)
+{
+       (void) fcntl(fd, F_SETFD, FD_CLOEXEC);
+       if (push) {
+               pushfile();
+               parsefile->buf = 0;
+       }
+       parsefile->fd = fd;
+       if (parsefile->buf == NULL)
+               parsefile->buf = ckmalloc(IBUFSIZ);
+       parselleft = parsenleft = 0;
+       plinno = 1;
+}
+
 
 /*
- * Wait for a process to terminate.
+ * Like setinputfile, but takes input from a string.
  */
 
+static void
+setinputstring(char *string)
+{
+       INTOFF;
+       pushfile();
+       parsenextc = string;
+       parsenleft = strlen(string);
+       parsefile->buf = NULL;
+       plinno = 1;
+       INTON;
+}
+
+
 /*
- * Do a wait system call.  If job control is compiled in, we accept
- * stopped processes.  If block is zero, we return a value of zero
- * rather than blocking.
- *
- * System V doesn't have a non-blocking wait system call.  It does
- * have a SIGCLD signal that is sent to a process when one of it's
- * children dies.  The obvious way to use SIGCLD would be to install
- * a handler for SIGCLD which simply bumped a counter when a SIGCLD
- * was received, and have waitproc bump another counter when it got
- * the status of a process.  Waitproc would then know that a wait
- * system call would not block if the two counters were different.
- * This approach doesn't work because if a process has children that
- * have not been waited for, System V will send it a SIGCLD when it
- * installs a signal handler for SIGCLD.  What this means is that when
- * a child exits, the shell will be sent SIGCLD signals continuously
- * until is runs out of stack space, unless it does a wait call before
- * restoring the signal handler.  The code below takes advantage of
- * this (mis)feature by installing a signal handler for SIGCLD and
- * then checking to see whether it was called.  If there are any
- * children to be waited for, it will be.
- *
+ * To handle the "." command, a stack of input files is used.  Pushfile
+ * adds a new entry to the stack and popfile restores the previous level.
  */
 
-static inline int
-waitproc(int block, int *status)
+static void
+pushfile(void)
 {
-       int flags;
+       struct parsefile *pf;
 
-       flags = 0;
-#ifdef CONFIG_ASH_JOB_CONTROL
-       if (jobctl)
-               flags |= WUNTRACED;
-#endif
-       if (block == 0)
-               flags |= WNOHANG;
-       return wait3(status, flags, (struct rusage *)NULL);
+       parsefile->nleft = parsenleft;
+       parsefile->lleft = parselleft;
+       parsefile->nextc = parsenextc;
+       parsefile->linno = plinno;
+       pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile));
+       pf->prev = parsefile;
+       pf->fd = -1;
+       pf->strpush = NULL;
+       pf->basestrpush.prev = NULL;
+       parsefile = pf;
 }
 
-static int
-dowait(int block, struct job *job)
+
+static void
+popfile(void)
 {
-       int pid;
-       int status;
-       struct procstat *sp;
-       struct job *jp;
-       struct job *thisjob;
-       int done;
-       int stopped;
-       int core;
-       int sig;
+       struct parsefile *pf = parsefile;
 
-       TRACE(("dowait(%d) called\n", block));
-       do {
-               pid = waitproc(block, &status);
-               TRACE(("wait returns %d, status=%d\n", pid, status));
-       } while (!(block & 2) && pid == -1 && errno == EINTR);
-       if (pid <= 0)
-               return pid;
        INTOFF;
-       thisjob = NULL;
-       for (jp = jobtab ; jp < jobtab + njobs ; jp++) {
-               if (jp->used) {
-                       done = 1;
-                       stopped = 1;
-                       for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) {
-                               if (sp->pid == -1)
-                                       continue;
-                               if (sp->pid == pid) {
-                                       TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", pid, sp->status, status));
-                                       sp->status = status;
-                                       thisjob = jp;
-                               }
-                               if (sp->status == -1)
-                                       stopped = 0;
-                               else if (WIFSTOPPED(sp->status))
-                                       done = 0;
-                       }
-                       if (stopped) {          /* stopped or done */
-                               int state = done? JOBDONE : CONFIG_ASH_JOB_CONTROLTOPPED;
-                               if (jp->state != state) {
-                                       TRACE(("Job %d: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state));
-                                       jp->state = state;
-#ifdef CONFIG_ASH_JOB_CONTROL
-                                       if (done && curjob == jp - jobtab + 1)
-                                               curjob = 0;             /* no current job */
-#endif
-                               }
-                       }
-               }
-       }
+       if (pf->fd >= 0)
+               close(pf->fd);
+       if (pf->buf)
+               ckfree(pf->buf);
+       while (pf->strpush)
+               popstring();
+       parsefile = pf->prev;
+       ckfree(pf);
+       parsenleft = parsefile->nleft;
+       parselleft = parsefile->lleft;
+       parsenextc = parsefile->nextc;
+       plinno = parsefile->linno;
        INTON;
-       if (! rootshell || ! iflag || (job && thisjob == job)) {
-               core = WCOREDUMP(status);
-#ifdef CONFIG_ASH_JOB_CONTROL
-               if (WIFSTOPPED(status)) sig = WSTOPSIG(status);
-               else
-#endif
-               if (WIFEXITED(status)) sig = 0;
-               else sig = WTERMSIG(status);
-
-               if (sig != 0 && sig != SIGINT && sig != SIGPIPE) {
-                       if (thisjob != job)
-                               out2fmt("%d: ", pid);
-#ifdef CONFIG_ASH_JOB_CONTROL
-                       if (sig == SIGTSTP && rootshell && iflag)
-                               out2fmt("%%%ld ",
-                                   (long)(job - jobtab + 1));
-#endif
-                       if (sig < NSIG && sys_siglist[sig])
-                               out2str(sys_siglist[sig]);
-                       else
-                               out2fmt("Signal %d", sig);
-                       if (core)
-                               out2str(" - core dumped");
-                       out2c('\n');
-               } else {
-                       TRACE(("Not printing status: status=%d, sig=%d\n",
-                              status, sig));
-               }
-       } else {
-               TRACE(("Not printing status, rootshell=%d, job=0x%x\n", rootshell, job));
-               if (thisjob)
-                       thisjob->changed = 1;
-       }
-       return pid;
 }
 
 
-
-
 /*
- * return 1 if there are stopped jobs, otherwise 0
+ * Return to top level.
  */
-static int
-stoppedjobs(void)
-{
-       int jobno;
-       struct job *jp;
 
-       if (job_warning)
-               return (0);
-       for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) {
-               if (jp->used == 0)
-                       continue;
-               if (jp->state == CONFIG_ASH_JOB_CONTROLTOPPED) {
-                       out2str("You have stopped jobs.\n");
-                       job_warning = 2;
-                       return (1);
-               }
-       }
-
-       return (0);
+static void
+popallfiles(void)
+{
+       while (parsefile != &basepf)
+               popfile();
 }
 
+
 /*
- * Return a string identifying a command (to be printed by the
- * jobs command.
+ * Close the file(s) that the shell is reading commands from.  Called
+ * after a fork is done.
  */
 
-static char *cmdnextc;
-static int cmdnleft;
-#define MAXCMDTEXT      200
+static void
+closescript(void)
+{
+       popallfiles();
+       if (parsefile->fd > 0) {
+               close(parsefile->fd);
+               parsefile->fd = 0;
+       }
+}
+
+/*      jobs.c    */
+
+/* mode flags for set_curjob */
+#define CUR_DELETE 2
+#define CUR_RUNNING 1
+#define CUR_STOPPED 0
+
+/* mode flags for dowait */
+#define DOWAIT_NORMAL 0
+#define DOWAIT_BLOCK 1
+
+/* array of jobs */
+static struct job *jobtab;
+/* size of array */
+static unsigned njobs;
+#if JOBS
+/* pgrp of shell on invocation */
+static int initialpgrp;
+static int ttyfd = -1;
+#endif
+/* current job */
+static struct job *curjob;
+/* number of presumed living untracked jobs */
+static int jobless;
+
+static void set_curjob(struct job *, unsigned);
+#if JOBS
+static int restartjob(struct job *, int);
+static void xtcsetpgrp(int, pid_t);
+static char *commandtext(union node *);
+static void cmdlist(union node *, int);
+static void cmdtxt(union node *);
+static void cmdputs(const char *);
+static void showpipe(struct job *, FILE *);
+#endif
+static int sprint_status(char *, int, int);
+static void freejob(struct job *);
+static struct job *getjob(const char *, int);
+static struct job *growjobtab(void);
+static void forkchild(struct job *, union node *, int);
+static void forkparent(struct job *, union node *, int, pid_t);
+static int dowait(int, struct job *);
+static int getstatus(struct job *);
 
 static void
-cmdputs(const char *s)
+set_curjob(struct job *jp, unsigned mode)
 {
-       const char *p;
-       char *q;
-       char c;
-       int subtype = 0;
+       struct job *jp1;
+       struct job **jpp, **curp;
 
-       if (cmdnleft <= 0)
-               return;
-       p = s;
-       q = cmdnextc;
-       while ((c = *p++) != '\0') {
-               if (c == CTLESC)
-                       *q++ = *p++;
-               else if (c == CTLVAR) {
-                       *q++ = '$';
-                       if (--cmdnleft > 0)
-                               *q++ = '{';
-                       subtype = *p++;
-               } else if (c == '=' && subtype != 0) {
-                       *q++ = "}-+?="[(subtype & VSTYPE) - VSNORMAL];
-                       subtype = 0;
-               } else if (c == CTLENDVAR) {
-                       *q++ = '}';
-               } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE)
-                       cmdnleft++;             /* ignore it */
-               else
-                       *q++ = c;
-               if (--cmdnleft <= 0) {
-                       *q++ = '.';
-                       *q++ = '.';
-                       *q++ = '.';
+       /* first remove from list */
+       jpp = curp = &curjob;
+       do {
+               jp1 = *jpp;
+               if (jp1 == jp)
                        break;
-               }
+               jpp = &jp1->prev_job;
+       } while (1);
+       *jpp = jp1->prev_job;
+
+       /* Then re-insert in correct position */
+       jpp = curp;
+       switch (mode) {
+       default:
+#ifdef DEBUG
+               abort();
+#endif
+       case CUR_DELETE:
+               /* job being deleted */
+               break;
+       case CUR_RUNNING:
+               /* newly created job or backgrounded job,
+                  put after all stopped jobs. */
+               do {
+                       jp1 = *jpp;
+#if JOBS
+                       if (!jp1 || jp1->state != JOBSTOPPED)
+#endif
+                               break;
+                       jpp = &jp1->prev_job;
+               } while (1);
+               /* FALLTHROUGH */
+#if JOBS
+       case CUR_STOPPED:
+#endif
+               /* newly stopped job - becomes curjob */
+               jp->prev_job = *jpp;
+               *jpp = jp;
+               break;
        }
-       cmdnextc = q;
 }
 
-#define CMDTXT_TABLE
-#ifdef CMDTXT_TABLE
+#if JOBS
 /*
- * To collect a lot of redundant code in cmdtxt() case statements, we
- * implement a mini language here.  Each type of node struct has an
- * associated instruction sequence that operates on its members via
- * their offsets.  The instruction are pack in unsigned chars with
- * format   IIDDDDDE   where the bits are
- *   I : part of the instruction opcode, which are
- *       00 : member is a pointer to another node -- process it recursively
- *       40 : member is a pointer to a char string -- output it
- *       80 : output the string whose index is stored in the data field
- *       CC : flag signaling that this case needs external processing
- *   D : data - either the (shifted) index of a fixed string to output or
- *              the actual offset of the member to operate on in the struct
- *              (since we assume bit 0 is set, the offset is not shifted)
- *   E : flag signaling end of instruction sequence
+ * Turn job control on and off.
  *
- * WARNING: In order to handle larger offsets for 64bit archs, this code
- *          assumes that no offset can be an odd number and stores the
- *          end-of-instructions flag in bit 0.
- */
-
-#define CMDTXT_NOMORE      0x01 /* NOTE: no offset should be odd */
-#define CMDTXT_CHARPTR     0x40
-#define CMDTXT_STRING      0x80
-#define CMDTXT_SPECIAL     0xC0
-#define CMDTXT_OFFSETMASK  0x3E
-
-static const char * const cmdtxt_strings[] = {
- /* 0     1    2    3       4       5      6          7     */
-       "; ", "(", ")", " && ", " || ", "if ", "; then ", "...",
- /* 8         9        10       11        12      13       */
-    "while ", "; do ", "; done", "until ", "for ", " in ...",
- /* 14       15     16        17     */
-       "case ", "???", "() ...", "<<..."
-};
+ * Note:  This code assumes that the third arg to ioctl is a character
+ * pointer, which is true on Berkeley systems but not System V.  Since
+ * System V doesn't have job control yet, this isn't a problem now.
+ *
+ * Called with interrupts off.
+ */
 
-static const char * const redir_strings[] = {
-       ">", "<", "<>", ">>", ">|", ">&", "<&"
-};
+void
+setjobctl(int on)
+{
+       int fd;
+       int pgrp;
 
-static const unsigned char cmdtxt_ops[] = {
-#define CMDTXT_NSEMI    0
-       offsetof(union node, nbinary.ch1),
-       0|CMDTXT_STRING,
-       offsetof(union node, nbinary.ch2)|CMDTXT_NOMORE,
-#define CMDTXT_NCMD     (CMDTXT_NSEMI + 3)
-#define CMDTXT_NPIPE    (CMDTXT_NCMD)
-#define  CMDTXT_NCASE    (CMDTXT_NCMD)
-#define  CMDTXT_NTO      (CMDTXT_NCMD)
-#define  CMDTXT_NFROM    (CMDTXT_NCMD)
-#define  CMDTXT_NFROMTO  (CMDTXT_NCMD)
-#define  CMDTXT_NAPPEND  (CMDTXT_NCMD)
-#define  CMDTXT_NTOOV    (CMDTXT_NCMD)
-#define  CMDTXT_NTOFD    (CMDTXT_NCMD)
-#define  CMDTXT_NFROMFD  (CMDTXT_NCMD)
-       CMDTXT_SPECIAL,
-#define CMDTXT_NREDIR   (CMDTXT_NPIPE + 1)
-#define CMDTXT_NBACKGND (CMDTXT_NREDIR)
-       offsetof(union node, nredir.n)|CMDTXT_NOMORE,
-#define CMDTXT_NSUBSHELL (CMDTXT_NBACKGND + 1)
-       (1*2)|CMDTXT_STRING,
-       offsetof(union node, nredir.n),
-       (2*2)|CMDTXT_STRING|CMDTXT_NOMORE,
-#define CMDTXT_NAND     (CMDTXT_NSUBSHELL + 3)
-       offsetof(union node, nbinary.ch1),
-       (3*2)|CMDTXT_STRING,
-       offsetof(union node, nbinary.ch2)|CMDTXT_NOMORE,
-#define CMDTXT_NOR      (CMDTXT_NAND + 3)
-       offsetof(union node, nbinary.ch1),
-       (4*2)|CMDTXT_STRING,
-       offsetof(union node, nbinary.ch2)|CMDTXT_NOMORE,
-#define CMDTXT_NIF      (CMDTXT_NOR + 3)
-       (5*2)|CMDTXT_STRING,
-       offsetof(union node, nif.test),
-       (6*2)|CMDTXT_STRING,
-       offsetof(union node, nif.ifpart),
-       (7*2)|CMDTXT_STRING|CMDTXT_NOMORE,
-#define CMDTXT_NWHILE   (CMDTXT_NIF + 5)
-       (8*2)|CMDTXT_STRING,
-       offsetof(union node, nbinary.ch1),
-       (9*2)|CMDTXT_STRING,
-       offsetof(union node, nbinary.ch2),
-       (10*2)|CMDTXT_STRING|CMDTXT_NOMORE,
-#define CMDTXT_NUNTIL   (CMDTXT_NWHILE + 5)
-       (11*2)|CMDTXT_STRING,
-       offsetof(union node, nbinary.ch1),
-       (9*2)|CMDTXT_STRING,
-       offsetof(union node, nbinary.ch2),
-       (10*2)|CMDTXT_STRING|CMDTXT_NOMORE,
-#define CMDTXT_NFOR     (CMDTXT_NUNTIL + 5)
-       (12*2)|CMDTXT_STRING,
-       offsetof(union node, nfor.var)|CMDTXT_CHARPTR,
-       (13*2)|CMDTXT_STRING|CMDTXT_NOMORE,
-#define CMDTXT_NCLIST   (CMDTXT_NFOR + 3) /* TODO: IS THIS CORRECT??? */
-#define  CMDTXT_NNOT     (CMDTXT_NCLIST)        /* TODO: IS THIS CORRECT??? */
-       (15*2)|CMDTXT_STRING|CMDTXT_NOMORE,
-#define CMDTXT_NDEFUN   (CMDTXT_NCLIST + 1)
-       offsetof(union node, narg.text)|CMDTXT_CHARPTR,
-       (16*2)|CMDTXT_STRING|CMDTXT_NOMORE,
-#define CMDTXT_NARG     (CMDTXT_NDEFUN + 2)
-       offsetof(union node, narg.text)|CMDTXT_CHARPTR|CMDTXT_NOMORE,
-#define CMDTXT_NHERE    (CMDTXT_NARG + 1)
-#define CMDTXT_NXHERE   (CMDTXT_NHERE)
-       (17*2)|CMDTXT_STRING|CMDTXT_NOMORE,
-};
+       if (on == jobctl || rootshell == 0)
+               return;
+       if (on) {
+               int ofd;
+               ofd = fd = open(_PATH_TTY, O_RDWR);
+               if (fd < 0) {
+                       fd += 3;
+                       while (!isatty(fd) && --fd >= 0)
+                               ;
+               }
+               fd = fcntl(fd, F_DUPFD, 10);
+               close(ofd);
+               if (fd < 0)
+                       goto out;
+               fcntl(fd, F_SETFD, FD_CLOEXEC);
+               do { /* while we are in the background */
+                       if ((pgrp = tcgetpgrp(fd)) < 0) {
+out:
+                               sh_warnx("can't access tty; job control turned off");
+                               mflag = on = 0;
+                               goto close;
+                       }
+                       if (pgrp == getpgrp())
+                               break;
+                       killpg(0, SIGTTIN);
+               } while (1);
+               initialpgrp = pgrp;
 
-#if CMDTXT_NXHERE != 36
-#error CMDTXT_NXHERE
-#endif
-
-static const unsigned char cmdtxt_ops_index[26] = {
-       CMDTXT_NSEMI,
-       CMDTXT_NCMD,
-       CMDTXT_NPIPE,
-       CMDTXT_NREDIR,
-       CMDTXT_NBACKGND,
-       CMDTXT_NSUBSHELL,
-       CMDTXT_NAND,
-       CMDTXT_NOR,
-       CMDTXT_NIF,
-       CMDTXT_NWHILE,
-       CMDTXT_NUNTIL,
-       CMDTXT_NFOR,
-       CMDTXT_NCASE,
-       CMDTXT_NCLIST,
-       CMDTXT_NDEFUN,
-       CMDTXT_NARG,
-       CMDTXT_NTO,
-       CMDTXT_NFROM,
-       CMDTXT_NFROMTO,
-       CMDTXT_NAPPEND,
-       CMDTXT_NTOOV,
-       CMDTXT_NTOFD,
-       CMDTXT_NFROMFD,
-       CMDTXT_NHERE,
-       CMDTXT_NXHERE,
-       CMDTXT_NNOT,
-};
+               setsignal(SIGTSTP);
+               setsignal(SIGTTOU);
+               setsignal(SIGTTIN);
+               pgrp = rootpid;
+               setpgid(0, pgrp);
+               xtcsetpgrp(fd, pgrp);
+       } else {
+               /* turning job control off */
+               fd = ttyfd;
+               pgrp = initialpgrp;
+               xtcsetpgrp(fd, pgrp);
+               setpgid(0, pgrp);
+               setsignal(SIGTSTP);
+               setsignal(SIGTTOU);
+               setsignal(SIGTTIN);
+close:
+               close(fd);
+               fd = -1;
+       }
+       ttyfd = fd;
+       jobctl = on;
+}
 
-static void
-cmdtxt(const union node *n)
+static int
+killcmd(int argc, char **argv)
 {
-       const char *p;
+       int signo = -1;
+       int list = 0;
+       int i;
+       pid_t pid;
+       struct job *jp;
 
-       if (n == NULL)
-               return;
+       if (argc <= 1) {
+usage:
+               sh_error(
+"Usage: kill [-s sigspec | -signum | -sigspec] [pid | job]... or\n"
+"kill -l [exitstatus]"
+               );
+       }
 
-       p = cmdtxt_ops + (int) cmdtxt_ops_index[n->type];
-       if ((*p & CMDTXT_SPECIAL) != CMDTXT_SPECIAL) { /* normal case */
-               do {
-                       if (*p & CMDTXT_STRING) { /* output fixed string */
-                               cmdputs(cmdtxt_strings[((int)(*p & CMDTXT_OFFSETMASK) >> 1)]);
-                       } else {
-                               const char *pf = ((const char *) n)
-                                                                 + ((int)(*p & CMDTXT_OFFSETMASK));
-                               if (*p & CMDTXT_CHARPTR) { /* output dynamic string */
-                                       cmdputs(*((const char **) pf));
-                               } else {                /* output field */
-                                       cmdtxt(*((const union node **) pf));
-                               }
-                       }
-               } while (!(*p++ & CMDTXT_NOMORE));
-       } else if (n->type == NCMD) {
-               union node *np;
-               for (np = n->ncmd.args ; np ; np = np->narg.next) {
-                       cmdtxt(np);
-                       if (np->narg.next)
-                               cmdputs(spcstr);
-               }
-               for (np = n->ncmd.redirect ; np ; np = np->nfile.next) {
-                       cmdputs(spcstr);
-                       cmdtxt(np);
-               }
-       } else if (n->type == NPIPE) {
-               struct nodelist *lp;
-               for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
-                       cmdtxt(lp->n);
-                       if (lp->next)
-                               cmdputs(" | ");
-               }
-       } else if (n->type == NCASE) {
-               cmdputs(cmdtxt_strings[14]);
-               cmdputs(n->ncase.expr->narg.text);
-               cmdputs(cmdtxt_strings[13]);
-       } else {
-#if (NTO != 16) || (NFROM != 17) || (NFROMTO != 18) || (NAPPEND != 19) || (NTOOV != 20) || (NTOFD != 21) || (NFROMFD != 22)
-#error Assumption violated regarding range and ordering of NTO ... NFROMFD!
-#endif
-               char s[2];
+       if (**++argv == '-') {
+               signo = get_signum(*argv + 1);
+               if (signo < 0) {
+                       int c;
 
+                       while ((c = nextopt("ls:")) != '\0')
+                               switch (c) {
+                               default:
 #ifdef DEBUG
-               assert((n->type >= NTO) && (n->type <= NFROMFD));
+                                       abort();
 #endif
+                               case 'l':
+                                       list = 1;
+                                       break;
+                               case 's':
+                                       signo = get_signum(optionarg);
+                                       if (signo < 0) {
+                                               sh_error(
+                                                       "invalid signal number or name: %s",
+                                                       optionarg
+                                               );
+                                       }
+                                       break;
+                               }
+                       argv = argptr;
+               } else
+                       argv++;
+       }
+
+       if (!list && signo < 0)
+               signo = SIGTERM;
+
+       if ((signo < 0 || !*argv) ^ list) {
+               goto usage;
+       }
+
+       if (list) {
+               const char *name;
 
-               p = redir_strings[n->type - NTO];
-               if (n->nfile.fd != ('>' == *p)) {
-                       s[0] = n->nfile.fd + '0';
-                       s[1] = '\0';
-                       cmdputs(s);
+               if (!*argv) {
+                       for (i = 1; i < NSIG; i++) {
+                               name = get_signame(i);
+                               if (isdigit(*name))
+                                       out1fmt(snlfmt, name);
+                       }
+                       return 0;
                }
-               cmdputs(p);
-               if (n->type >= NTOFD) {
-                       s[0] = n->ndup.dupfd + '0';
-                       s[1] = '\0';
-                       cmdputs(s);
+               name = get_signame(signo);
+               if (isdigit(*name))
+                       out1fmt(snlfmt, name);
+               else
+                       sh_error("invalid signal number or exit status: %s", *argptr);
+               return 0;
+       }
+
+       i = 0;
+       do {
+               if (**argv == '%') {
+                       jp = getjob(*argv, 0);
+                       pid = -jp->ps[0].pid;
                } else {
-                       cmdtxt(n->nfile.fname);
+                       pid = **argv == '-' ?
+                               -number(*argv + 1) : number(*argv);
                }
-       }
+               if (kill(pid, signo) != 0) {
+                       sh_warnx("(%d) - %m", pid);
+                       i = 1;
+               }
+       } while (*++argv);
+
+       return i;
 }
-#else  /* CMDTXT_TABLE */
-static void
-cmdtxt(const union node *n)
+#endif /* JOBS */
+
+#if defined(JOBS) || defined(DEBUG)
+static int
+jobno(const struct job *jp)
 {
-       union node *np;
-       struct nodelist *lp;
-       const char *p;
-       int i;
-       char s[2];
+       return jp - jobtab + 1;
+}
+#endif
 
-       if (n == NULL)
-               return;
-       switch (n->type) {
-       case NSEMI:
-               cmdtxt(n->nbinary.ch1);
-               cmdputs("; ");
-               cmdtxt(n->nbinary.ch2);
-               break;
-       case NAND:
-               cmdtxt(n->nbinary.ch1);
-               cmdputs(" && ");
-               cmdtxt(n->nbinary.ch2);
-               break;
-       case NOR:
-               cmdtxt(n->nbinary.ch1);
-               cmdputs(" || ");
-               cmdtxt(n->nbinary.ch2);
-               break;
-       case NPIPE:
-               for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
-                       cmdtxt(lp->n);
-                       if (lp->next)
-                               cmdputs(" | ");
-               }
-               break;
-       case NSUBSHELL:
-               cmdputs("(");
-               cmdtxt(n->nredir.n);
-               cmdputs(")");
-               break;
-       case NREDIR:
-       case NBACKGND:
-               cmdtxt(n->nredir.n);
-               break;
-       case NIF:
-               cmdputs("if ");
-               cmdtxt(n->nif.test);
-               cmdputs("; then ");
-               cmdtxt(n->nif.ifpart);
-               cmdputs("...");
-               break;
-       case NWHILE:
-               cmdputs("while ");
-               goto until;
-       case NUNTIL:
-               cmdputs("until ");
-until:
-               cmdtxt(n->nbinary.ch1);
-               cmdputs("; do ");
-               cmdtxt(n->nbinary.ch2);
-               cmdputs("; done");
-               break;
-       case NFOR:
-               cmdputs("for ");
-               cmdputs(n->nfor.var);
-               cmdputs(" in ...");
-               break;
-       case NCASE:
-               cmdputs("case ");
-               cmdputs(n->ncase.expr->narg.text);
-               cmdputs(" in ...");
-               break;
-       case NDEFUN:
-               cmdputs(n->narg.text);
-               cmdputs("() ...");
-               break;
-       case NCMD:
-               for (np = n->ncmd.args ; np ; np = np->narg.next) {
-                       cmdtxt(np);
-                       if (np->narg.next)
-                               cmdputs(spcstr);
+#if JOBS
+static int
+fgcmd(int argc, char **argv)
+{
+       struct job *jp;
+       FILE *out;
+       int mode;
+       int retval;
+
+       mode = (**argv == 'f') ? FORK_FG : FORK_BG;
+       nextopt(nullstr);
+       argv = argptr;
+       out = stdout;
+       do {
+               jp = getjob(*argv, 1);
+               if (mode == FORK_BG) {
+                       set_curjob(jp, CUR_RUNNING);
+                       fprintf(out, "[%d] ", jobno(jp));
                }
-               for (np = n->ncmd.redirect ; np ; np = np->nfile.next) {
-                       cmdputs(spcstr);
-                       cmdtxt(np);
+               outstr(jp->ps->cmd, out);
+               showpipe(jp, out);
+               retval = restartjob(jp, mode);
+       } while (*argv && *++argv);
+       return retval;
+}
+
+static int bgcmd(int, char **) __attribute__((__alias__("fgcmd")));
+
+
+static int
+restartjob(struct job *jp, int mode)
+{
+       struct procstat *ps;
+       int i;
+       int status;
+       pid_t pgid;
+
+       INTOFF;
+       if (jp->state == JOBDONE)
+               goto out;
+       jp->state = JOBRUNNING;
+       pgid = jp->ps->pid;
+       if (mode == FORK_FG)
+               xtcsetpgrp(ttyfd, pgid);
+       killpg(pgid, SIGCONT);
+       ps = jp->ps;
+       i = jp->nprocs;
+       do {
+               if (WIFSTOPPED(ps->status)) {
+                       ps->status = -1;
                }
-               break;
-       case NARG:
-               cmdputs(n->narg.text);
-               break;
-       case NTO:
-               p = ">";  i = 1;  goto redir;
-       case NAPPEND:
-               p = ">>";  i = 1;  goto redir;
-       case NTOFD:
-               p = ">&";  i = 1;  goto redir;
-       case NTOOV:
-               p = ">|";  i = 1;  goto redir;
-       case NFROM:
-               p = "<";  i = 0;  goto redir;
-       case NFROMFD:
-               p = "<&";  i = 0;  goto redir;
-       case NFROMTO:
-               p = "<>";  i = 0;  goto redir;
-redir:
-               if (n->nfile.fd != i) {
-                       s[0] = n->nfile.fd + '0';
-                       s[1] = '\0';
-                       cmdputs(s);
+       } while (ps++, --i);
+out:
+       status = (mode == FORK_FG) ? waitforjob(jp) : 0;
+       INTON;
+       return status;
+}
+#endif
+
+static int
+sprint_status(char *s, int status, int sigonly)
+{
+       int col;
+       int st;
+
+       col = 0;
+       if (!WIFEXITED(status)) {
+#if JOBS
+               if (WIFSTOPPED(status))
+                       st = WSTOPSIG(status);
+               else
+#endif
+                       st = WTERMSIG(status);
+               if (sigonly) {
+                       if (st == SIGINT || st == SIGPIPE)
+                               goto out;
+#if JOBS
+                       if (WIFSTOPPED(status))
+                               goto out;
+#endif
                }
-               cmdputs(p);
-               if (n->type == NTOFD || n->type == NFROMFD) {
-                       s[0] = n->ndup.dupfd + '0';
-                       s[1] = '\0';
-                       cmdputs(s);
-               } else {
-                       cmdtxt(n->nfile.fname);
+               st &= 0x7f;
+               col = fmtstr(s, 32, strsignal(st));
+               if (WCOREDUMP(status)) {
+                       col += fmtstr(s + col, 16, " (core dumped)");
                }
-               break;
-       case NHERE:
-       case NXHERE:
-               cmdputs("<<...");
-               break;
-       default:
-               cmdputs("???");
-               break;
+       } else if (!sigonly) {
+               st = WEXITSTATUS(status);
+               if (st)
+                       col = fmtstr(s, 16, "Done(%d)", st);
+               else
+                       col = fmtstr(s, 16, "Done");
        }
+
+out:
+       return col;
 }
-#endif /* CMDTXT_TABLE */
 
-static char *
-commandtext(const union node *n)
+#if JOBS
+static void
+showjob(FILE *out, struct job *jp, int mode)
 {
-       char *name;
+       struct procstat *ps;
+       struct procstat *psend;
+       int col;
+       int indent;
+       char s[80];
 
-       cmdnextc = name = xmalloc(MAXCMDTEXT);
-       cmdnleft = MAXCMDTEXT - 4;
-       cmdtxt(n);
-       *cmdnextc = '\0';
-       return name;
+       ps = jp->ps;
+
+       if (mode & SHOW_PGID) {
+               /* just output process (group) id of pipeline */
+               fprintf(out, "%d\n", ps->pid);
+               return;
+       }
+
+       col = fmtstr(s, 16, "[%d]   ", jobno(jp));
+       indent = col;
+
+       if (jp == curjob)
+               s[col - 2] = '+';
+       else if (curjob && jp == curjob->prev_job)
+               s[col - 2] = '-';
+
+       if (mode & SHOW_PID)
+               col += fmtstr(s + col, 16, "%d ", ps->pid);
+
+       psend = ps + jp->nprocs;
+
+       if (jp->state == JOBRUNNING) {
+               scopy("Running", s + col);
+               col += strlen("Running");
+       } else {
+               int status = psend[-1].status;
+#if JOBS
+               if (jp->state == JOBSTOPPED)
+                       status = jp->stopstatus;
+#endif
+               col += sprint_status(s + col, status, 0);
+       }
+
+       goto start;
+
+       do {
+               /* for each process */
+               col = fmtstr(s, 48, " |\n%*c%d ", indent, ' ', ps->pid) - 3;
+
+start:
+               fprintf(out, "%s%*c%s",
+                       s, 33 - col >= 0 ? 33 - col : 0, ' ', ps->cmd
+               );
+               if (!(mode & SHOW_PID)) {
+                       showpipe(jp, out);
+                       break;
+               }
+               if (++ps == psend) {
+                       outcslow('\n', out);
+                       break;
+               }
+       } while (1);
+
+       jp->changed = 0;
+
+       if (jp->state == JOBDONE) {
+               TRACE(("showjob: freeing job %d\n", jobno(jp)));
+               freejob(jp);
+       }
 }
 
 
-static void waitonint(int sig) {
-       intreceived = 1;
-       return;
+static int
+jobscmd(int argc, char **argv)
+{
+       int mode, m;
+       FILE *out;
+
+       mode = 0;
+       while ((m = nextopt("lp")))
+               if (m == 'l')
+                       mode = SHOW_PID;
+               else
+                       mode = SHOW_PGID;
+
+       out = stdout;
+       argv = argptr;
+       if (*argv)
+               do
+                       showjob(out, getjob(*argv,0), mode);
+               while (*++argv);
+       else
+               showjobs(out, mode);
+
+       return 0;
 }
 
-#ifdef CONFIG_ASH_MAIL
 
 /*
- * Routines to check for mail.
+ * Print a list of jobs.  If "change" is nonzero, only print jobs whose
+ * statuses have changed since the last call to showjobs.
  */
 
+static void
+showjobs(FILE *out, int mode)
+{
+       struct job *jp;
 
-#define MAXMBOXES 10
-
-
-static int nmboxes;                     /* number of mailboxes */
-static time_t mailtime[MAXMBOXES];      /* times of mailboxes */
+       TRACE(("showjobs(%x) called\n", mode));
 
+       /* If not even one one job changed, there is nothing to do */
+       while (dowait(DOWAIT_NORMAL, NULL) > 0)
+               continue;
 
+       for (jp = curjob; jp; jp = jp->prev_job) {
+               if (!(mode & SHOW_CHANGED) || jp->changed)
+                       showjob(out, jp, mode);
+       }
+}
+#endif /* JOBS */
 
 /*
- * Print appropriate message(s) if mail has arrived.  If the argument is
- * nozero, then the value of MAIL has changed, so we just update the
- * values.
+ * Mark a job structure as unused.
  */
 
 static void
-chkmail(int silent)
+freejob(struct job *jp)
 {
+       struct procstat *ps;
        int i;
-       const char *mpath;
-       char *p;
-       char *q;
-       struct stackmark smark;
-       struct stat statb;
 
-       if (silent)
-               nmboxes = 10;
-       if (nmboxes == 0)
-               return;
-       setstackmark(&smark);
-       mpath = mpathset()? mpathval() : mailval();
-       for (i = 0 ; i < nmboxes ; i++) {
-               p = padvance(&mpath, nullstr);
-               if (p == NULL)
-                       break;
-               if (*p == '\0')
-                       continue;
-               for (q = p ; *q ; q++);
-#ifdef DEBUG
-               if (q[-1] != '/')
-                       abort();
-#endif
-               q[-1] = '\0';                   /* delete trailing '/' */
-               if (stat(p, &statb) < 0)
-                       statb.st_size = 0;
-               if (statb.st_size > mailtime[i] && ! silent) {
-                       out2fmt(snlfmt,
-                               pathopt? pathopt : "you have mail");
-               }
-               mailtime[i] = statb.st_size;
+       INTOFF;
+       for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) {
+               if (ps->cmd != nullstr)
+                       ckfree(ps->cmd);
        }
-       nmboxes = i;
-       popstackmark(&smark);
+       if (jp->ps != &jp->ps0)
+               ckfree(jp->ps);
+       jp->used = 0;
+       set_curjob(jp, CUR_DELETE);
+       INTON;
 }
 
-#endif /* CONFIG_ASH_MAIL */
 
-#define PROFILE 0
+static int
+waitcmd(int argc, char **argv)
+{
+       struct job *job;
+       int retval;
+       struct job *jp;
 
-#if PROFILE
-static short profile_buf[16384];
-extern int etext();
-#endif
+       EXSIGON();
+
+       nextopt(nullstr);
+       retval = 0;
+
+       argv = argptr;
+       if (!*argv) {
+               /* wait for all jobs */
+               for (;;) {
+                       jp = curjob;
+                       while (1) {
+                               if (!jp) {
+                                       /* no running procs */
+                                       goto out;
+                               }
+                               if (jp->state == JOBRUNNING)
+                                       break;
+                               jp->waited = 1;
+                               jp = jp->prev_job;
+                       }
+                       dowait(DOWAIT_BLOCK, 0);
+               }
+       }
+
+       retval = 127;
+       do {
+               if (**argv != '%') {
+                       pid_t pid = number(*argv);
+                       job = curjob;
+                       goto start;
+                       do {
+                               if (job->ps[job->nprocs - 1].pid == pid)
+                                       break;
+                               job = job->prev_job;
+start:
+                               if (!job)
+                                       goto repeat;
+                       } while (1);
+               } else
+                       job = getjob(*argv, 0);
+               /* loop until process terminated or stopped */
+               while (job->state == JOBRUNNING)
+                       dowait(DOWAIT_BLOCK, 0);
+               job->waited = 1;
+               retval = getstatus(job);
+repeat:
+               ;
+       } while (*++argv);
 
-static void read_profile (const char *);
-static void cmdloop (int);
-static void options (int);
-static void setoption (int, int);
-static void procargs (int, char **);
+out:
+       return retval;
+}
 
 
 /*
- * Main routine.  We initialize things, parse the arguments, execute
- * profiles if we're a login shell, and then call cmdloop to execute
- * commands.  The setjmp call sets up the location to jump to when an
- * exception occurs.  When an exception occurs the variable "state"
- * is used to figure out how far we had gotten.
+ * Convert a job name to a job structure.
  */
 
-int
-ash_main(int argc, char **argv)
+static struct job *
+getjob(const char *name, int getctl)
 {
-       struct jmploc jmploc;
-       struct stackmark smark;
-       volatile int state;
-       const char *shinit;
+       struct job *jp;
+       struct job *found;
+       const char *err_msg = "No such job: %s";
+       unsigned num;
+       int c;
+       const char *p;
+       char *(*match)(const char *, const char *);
 
-       BLTINCMD = find_builtin("builtin");
-       EXECCMD = find_builtin("exec");
-       EVALCMD = find_builtin("eval");
+       jp = curjob;
+       p = name;
+       if (!p)
+               goto currentjob;
 
-#ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
-       unsetenv("PS1");
-       unsetenv("PS2");
-#endif
+       if (*p != '%')
+               goto err;
 
-#if PROFILE
-       monitor(4, etext, profile_buf, sizeof profile_buf, 50);
-#endif
-#if defined(linux) || defined(__GNU__)
-       signal(SIGCHLD, SIG_DFL);
-#endif
-       state = 0;
-       if (setjmp(jmploc.loc)) {
-               INTOFF;
-               /*
-                * When a shell procedure is executed, we raise the
-                * exception EXSHELLPROC to clean up before executing
-                * the shell procedure.
-                */
-               if (exception == EXSHELLPROC) {
-                       rootpid = getpid();
-                       rootshell = 1;
-                       minusc = NULL;
-                       state = 3;
-               } else {
-                       if (exception == EXEXEC) {
-                               exitstatus = exerrno;
-                       } else if (exception == EXERROR) {
-                               exitstatus = 2;
-                       }
-                   if (state == 0 || iflag == 0 || ! rootshell)
-                           exitshell(exitstatus);
-               }
-               reset();
-               if (exception == EXINT) {
-                       out2c('\n');
+       c = *++p;
+       if (!c)
+               goto currentjob;
+
+       if (!p[1]) {
+               if (c == '+' || c == '%') {
+currentjob:
+                       err_msg = "No current job";
+                       goto check;
+               } else if (c == '-') {
+                       if (jp)
+                               jp = jp->prev_job;
+                       err_msg = "No previous job";
+check:
+                       if (!jp)
+                               goto err;
+                       goto gotit;
                }
-               popstackmark(&smark);
-               FORCEINTON;                             /* enable interrupts */
-               if (state == 1)
-                       goto state1;
-               else if (state == 2)
-                       goto state2;
-               else if (state == 3)
-                       goto state3;
-               else
-                       goto state4;
-       }
-       handler = &jmploc;
-#ifdef DEBUG
-       opentrace();
-       trputs("Shell args:  ");  trargs(argv);
-#endif
-       rootpid = getpid();
-       rootshell = 1;
-       init();
-       setstackmark(&smark);
-       procargs(argc, argv);
-       if (argv[0] && argv[0][0] == '-') {
-               state = 1;
-               read_profile("/etc/profile");
-state1:
-               state = 2;
-               read_profile(".profile");
        }
-state2:
-       state = 3;
-#ifndef linux
-       if (getuid() == geteuid() && getgid() == getegid()) {
-#endif
-               if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') {
-                       state = 3;
-                       read_profile(shinit);
+
+       if (is_number(p)) {
+               num = atoi(p);
+               if (num < njobs) {
+                       jp = jobtab + num - 1;
+                       if (jp->used)
+                               goto gotit;
+                       goto err;
                }
-#ifndef linux
        }
-#endif
-state3:
-       state = 4;
-       if (sflag == 0 || minusc) {
-               static const char sigs[] =  {
-                   SIGINT, SIGQUIT, SIGHUP,
-#ifdef SIGTSTP
-                   SIGTSTP,
-#endif
-                   SIGPIPE
-               };
-#define SIGSSIZE ((sizeof(sigs)/sizeof(sigs[0])) - 1) /* trailing nul */
-               int i;
 
-               for (i = 0; i < SIGSSIZE; i++)
-                   setsignal(sigs[i]);
+       match = prefix;
+       if (*p == '?') {
+               match = strstr;
+               p++;
        }
 
-       if (minusc)
-               evalstring(minusc, 0);
-
-       if (sflag || minusc == NULL) {
-state4: /* XXX ??? - why isn't this before the "if" statement */
-               cmdloop(1);
+       found = 0;
+       while (1) {
+               if (!jp)
+                       goto err;
+               if (match(jp->ps[0].cmd, p)) {
+                       if (found)
+                               goto err;
+                       found = jp;
+                       err_msg = "%s: ambiguous";
+               }
+               jp = jp->prev_job;
        }
-#if PROFILE
-       monitor(0);
+
+gotit:
+#if JOBS
+       err_msg = "job %s not created under job control";
+       if (getctl && jp->jobctl == 0)
+               goto err;
 #endif
-       exitshell(exitstatus);
-       /* NOTREACHED */
+       return jp;
+err:
+       sh_error(err_msg, name);
 }
 
 
 /*
- * Read and execute commands.  "Top" is nonzero for the top level command
- * loop; it turns on prompting if the shell is interactive.
+ * Return a new job structure.
+ * Called with interrupts off.
  */
 
-static void
-cmdloop(int top)
+static struct job *
+makejob(union node *node, int nprocs)
 {
-       union node *n;
-       struct stackmark smark;
-       int inter;
-       int numeof = 0;
+       int i;
+       struct job *jp;
 
-       TRACE(("cmdloop(%d) called\n", top));
-       setstackmark(&smark);
-       for (;;) {
-               if (pendingsigs)
-                       dotrap();
-               inter = 0;
-               if (iflag && top) {
-                       inter++;
-                       showjobs(1);
-#ifdef CONFIG_ASH_MAIL
-                       chkmail(0);
-#endif
-                       flushall();
-               }
-               n = parsecmd(inter);
-               /* showtree(n); DEBUG */
-               if (n == NEOF) {
-                       if (!top || numeof >= 50)
-                               break;
-                       if (!stoppedjobs()) {
-                               if (!Iflag)
-                                       break;
-                               out2str("\nUse \"exit\" to leave shell.\n");
-                       }
-                       numeof++;
-               } else if (n != NULL && nflag == 0) {
-                       job_warning = (job_warning == 2) ? 1 : 0;
-                       numeof = 0;
-                       evaltree(n, 0);
-               }
-               popstackmark(&smark);
-               setstackmark(&smark);
-               if (evalskip == SKIPFILE) {
-                       evalskip = 0;
+       for (i = njobs, jp = jobtab ; ; jp++) {
+               if (--i < 0) {
+                       jp = growjobtab();
                        break;
                }
+               if (jp->used == 0)
+                       break;
+               if (jp->state != JOBDONE || !jp->waited)
+                       continue;
+#if JOBS
+               if (jobctl)
+                       continue;
+#endif
+               freejob(jp);
+               break;
        }
-       popstackmark(&smark);
+       memset(jp, 0, sizeof(*jp));
+#if JOBS
+       if (jobctl)
+               jp->jobctl = 1;
+#endif
+       jp->prev_job = curjob;
+       curjob = jp;
+       jp->used = 1;
+       jp->ps = &jp->ps0;
+       if (nprocs > 1) {
+               jp->ps = ckmalloc(nprocs * sizeof (struct procstat));
+       }
+       TRACE(("makejob(0x%lx, %d) returns %%%d\n", (long)node, nprocs,
+           jobno(jp)));
+       return jp;
 }
 
+static struct job *
+growjobtab(void)
+{
+       size_t len;
+       ptrdiff_t offset;
+       struct job *jp, *jq;
+
+       len = njobs * sizeof(*jp);
+       jq = jobtab;
+       jp = ckrealloc(jq, len + 4 * sizeof(*jp));
+
+       offset = (char *)jp - (char *)jq;
+       if (offset) {
+               /* Relocate pointers */
+               size_t l = len;
+
+               jq = (struct job *)((char *)jq + l);
+               while (l) {
+                       l -= sizeof(*jp);
+                       jq--;
+#define joff(p) ((struct job *)((char *)(p) + l))
+#define jmove(p) (p) = (void *)((char *)(p) + offset)
+                       if (xlikely(joff(jp)->ps == &jq->ps0))
+                               jmove(joff(jp)->ps);
+                       if (joff(jp)->prev_job)
+                               jmove(joff(jp)->prev_job);
+               }
+               if (curjob)
+                       jmove(curjob);
+#undef joff
+#undef jmove
+       }
+
+       njobs += 4;
+       jobtab = jp;
+       jp = (struct job *)((char *)jp + len);
+       jq = jp + 3;
+       do {
+               jq->used = 0;
+       } while (--jq >= jp);
+       return jp;
+}
 
 
 /*
- * Read /etc/profile or .profile.  Return on error.
+ * Fork off a subshell.  If we are doing job control, give the subshell its
+ * own process group.  Jp is a job structure that the job is to be added to.
+ * N is the command that will be evaluated by the child.  Both jp and n may
+ * be NULL.  The mode parameter can be one of the following:
+ *      FORK_FG - Fork off a foreground process.
+ *      FORK_BG - Fork off a background process.
+ *      FORK_NOJOB - Like FORK_FG, but don't give the process its own
+ *                   process group even if job control is on.
+ *
+ * When job control is turned off, background processes have their standard
+ * input redirected to /dev/null (except for the second and later processes
+ * in a pipeline).
+ *
+ * Called with interrupts off.
  */
 
-static void
-read_profile(const char *name)
+static inline void
+forkchild(struct job *jp, union node *n, int mode)
 {
-       int fd;
-       int xflag_save;
-       int vflag_save;
+       int oldlvl;
 
-       INTOFF;
-       if ((fd = open(name, O_RDONLY)) >= 0)
-               setinputfd(fd, 1);
-       INTON;
-       if (fd < 0)
-               return;
-       /* -q turns off -x and -v just when executing init files */
-       /* Note: Might do a little redundant work, but reduces code size. */
-       xflag_save = xflag;
-       vflag_save = vflag;
-       if (qflag)  {
-               vflag = xflag = 0;
+       TRACE(("Child shell %d\n", getpid()));
+       oldlvl = shlvl;
+       shlvl++;
+
+       closescript();
+       clear_traps();
+#if JOBS
+       /* do job control only in root shell */
+       jobctl = 0;
+       if (mode != FORK_NOJOB && jp->jobctl && !oldlvl) {
+               pid_t pgrp;
+
+               if (jp->nprocs == 0)
+                       pgrp = getpid();
+               else
+                       pgrp = jp->ps[0].pid;
+               /* This can fail because we are doing it in the parent also */
+               (void)setpgid(0, pgrp);
+               if (mode == FORK_FG)
+                       xtcsetpgrp(ttyfd, pgrp);
+               setsignal(SIGTSTP);
+               setsignal(SIGTTOU);
+       } else
+#endif
+       if (mode == FORK_BG) {
+               ignoresig(SIGINT);
+               ignoresig(SIGQUIT);
+               if (jp->nprocs == 0) {
+                       close(0);
+                       if (open(bb_dev_null, O_RDONLY) != 0)
+                               sh_error("Can't open %s", bb_dev_null);
+               }
        }
-       cmdloop(0);
-       xflag = xflag_save;
-       vflag = vflag_save;
-       popfile();
+       if (!oldlvl && iflag) {
+               setsignal(SIGINT);
+               setsignal(SIGQUIT);
+               setsignal(SIGTERM);
+       }
+       for (jp = curjob; jp; jp = jp->prev_job)
+               freejob(jp);
+       jobless = 0;
 }
 
+static inline void
+forkparent(struct job *jp, union node *n, int mode, pid_t pid)
+{
+       TRACE(("In parent shell:  child = %d\n", pid));
+       if (!jp) {
+               while (jobless && dowait(DOWAIT_NORMAL, 0) > 0);
+               jobless++;
+               return;
+       }
+#if JOBS
+       if (mode != FORK_NOJOB && jp->jobctl) {
+               int pgrp;
 
+               if (jp->nprocs == 0)
+                       pgrp = pid;
+               else
+                       pgrp = jp->ps[0].pid;
+               /* This can fail because we are doing it in the child also */
+               (void)setpgid(pid, pgrp);
+       }
+#endif
+       if (mode == FORK_BG) {
+               backgndpid = pid;               /* set $! */
+               set_curjob(jp, CUR_RUNNING);
+       }
+       if (jp) {
+               struct procstat *ps = &jp->ps[jp->nprocs++];
+               ps->pid = pid;
+               ps->status = -1;
+               ps->cmd = nullstr;
+#if JOBS
+               if (jobctl && n)
+                       ps->cmd = commandtext(n);
+#endif
+       }
+}
 
-/*
- * Read a file containing shell functions.
- */
-
-static void
-readcmdfile(const char *name)
+static int
+forkshell(struct job *jp, union node *n, int mode)
 {
-       int fd;
+       int pid;
 
-       INTOFF;
-       if ((fd = open(name, O_RDONLY)) >= 0)
-               setinputfd(fd, 1);
+       TRACE(("forkshell(%%%d, %p, %d) called\n", jobno(jp), n, mode));
+       pid = fork();
+       if (pid < 0) {
+               TRACE(("Fork failed, errno=%d", errno));
+               if (jp)
+                       freejob(jp);
+               sh_error("Cannot fork");
+       }
+       if (pid == 0)
+               forkchild(jp, n, mode);
        else
-               error("Can't open %s", name);
-       INTON;
-       cmdloop(0);
-       popfile();
+               forkparent(jp, n, mode, pid);
+       return pid;
 }
 
-
-
 /*
- * Take commands from a file.  To be compatable we should do a path
- * search for the file, which is necessary to find sub-commands.
+ * Wait for job to finish.
+ *
+ * Under job control we have the problem that while a child process is
+ * running interrupts generated by the user are sent to the child but not
+ * to the shell.  This means that an infinite loop started by an inter-
+ * active user may be hard to kill.  With job control turned off, an
+ * interactive user may place an interactive program inside a loop.  If
+ * the interactive program catches interrupts, the user doesn't want
+ * these interrupts to also abort the loop.  The approach we take here
+ * is to have the shell ignore interrupt signals while waiting for a
+ * foreground process to terminate, and then send itself an interrupt
+ * signal if the child process was terminated by an interrupt signal.
+ * Unfortunately, some programs want to do a bit of cleanup and then
+ * exit on interrupt; unless these processes terminate themselves by
+ * sending a signal to themselves (instead of calling exit) they will
+ * confuse this approach.
+ *
+ * Called with interrupts off.
  */
 
-static inline char *
-find_dot_file(char *mybasename)
+int
+waitforjob(struct job *jp)
 {
-       char *fullname;
-       const char *path = pathval();
-       struct stat statb;
-
-       /* don't try this for absolute or relative paths */
-       if (strchr(mybasename, '/'))
-               return mybasename;
+       int st;
 
-       while ((fullname = padvance(&path, mybasename)) != NULL) {
-               if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) {
-                       /*
-                        * Don't bother freeing here, since it will
-                        * be freed by the caller.
-                        */
-                       return fullname;
-               }
-               stunalloc(fullname);
+       TRACE(("waitforjob(%%%d) called\n", jobno(jp)));
+       while (jp->state == JOBRUNNING) {
+               dowait(DOWAIT_BLOCK, jp);
        }
-
-       /* not found in the PATH */
-       error("%s: not found", mybasename);
-       /* NOTREACHED */
+       st = getstatus(jp);
+#if JOBS
+       if (jp->jobctl) {
+               xtcsetpgrp(ttyfd, rootpid);
+               /*
+                * This is truly gross.
+                * If we're doing job control, then we did a TIOCSPGRP which
+                * caused us (the shell) to no longer be in the controlling
+                * session -- so we wouldn't have seen any ^C/SIGINT.  So, we
+                * intuit from the subprocess exit status whether a SIGINT
+                * occurred, and if so interrupt ourselves.  Yuck.  - mycroft
+                */
+               if (jp->sigint)
+                       raise(SIGINT);
+       }
+       if (jp->state == JOBDONE)
+#endif
+               freejob(jp);
+       return st;
 }
 
-static int
-dotcmd(int argc, char **argv)
-{
-       struct strlist *sp;
-       volatile struct shparam saveparam;
-       exitstatus = 0;
 
-       for (sp = cmdenviron; sp ; sp = sp->next)
-               setvareq(xstrdup(sp->text), VSTRFIXED|VTEXTFIXED);
-
-       if (argc >= 2) {                /* That's what SVR2 does */
-               char *fullname;
-               struct stackmark smark;
-
-               setstackmark(&smark);
-               fullname = find_dot_file(argv[1]);
-
-               if (argc>2) {
-                       saveparam = shellparam;
-                       shellparam.malloc = 0;
-                       shellparam.nparam = argc - 2;
-                       shellparam.p = argv + 2;
-               };
-
-               setinputfile(fullname, 1);
-               commandname = fullname;
-               cmdloop(0);
-               popfile();
+/*
+ * Do a wait system call.  If job control is compiled in, we accept
+ * stopped processes.  If block is zero, we return a value of zero
+ * rather than blocking.
+ *
+ * System V doesn't have a non-blocking wait system call.  It does
+ * have a SIGCLD signal that is sent to a process when one of it's
+ * children dies.  The obvious way to use SIGCLD would be to install
+ * a handler for SIGCLD which simply bumped a counter when a SIGCLD
+ * was received, and have waitproc bump another counter when it got
+ * the status of a process.  Waitproc would then know that a wait
+ * system call would not block if the two counters were different.
+ * This approach doesn't work because if a process has children that
+ * have not been waited for, System V will send it a SIGCLD when it
+ * installs a signal handler for SIGCLD.  What this means is that when
+ * a child exits, the shell will be sent SIGCLD signals continuously
+ * until is runs out of stack space, unless it does a wait call before
+ * restoring the signal handler.  The code below takes advantage of
+ * this (mis)feature by installing a signal handler for SIGCLD and
+ * then checking to see whether it was called.  If there are any
+ * children to be waited for, it will be.
+ *
+ * If neither SYSV nor BSD is defined, we don't implement nonblocking
+ * waits at all.  In this case, the user will not be informed when
+ * a background process until the next time she runs a real program
+ * (as opposed to running a builtin command or just typing return),
+ * and the jobs command may give out of date information.
+ */
 
-               if (argc>2) {
-                       freeparam(&shellparam);
-                       shellparam = saveparam;
-               };
+static inline int
+waitproc(int block, int *status)
+{
+       int flags = 0;
 
-               popstackmark(&smark);
-       }
-       return exitstatus;
+#if JOBS
+       if (jobctl)
+               flags |= WUNTRACED;
+#endif
+       if (block == 0)
+               flags |= WNOHANG;
+       return wait3(status, flags, (struct rusage *)NULL);
 }
 
+/*
+ * Wait for a process to terminate.
+ */
 
 static int
-exitcmd(int argc, char **argv)
-{
-       if (stoppedjobs())
-               return 0;
-       if (argc > 1)
-               exitstatus = number(argv[1]);
-       else
-               exitstatus = oexitstatus;
-       exitshell(exitstatus);
-       /* NOTREACHED */
-}
-
-static pointer
-stalloc(int nbytes)
+dowait(int block, struct job *job)
 {
-       char *p;
-
-       nbytes = ALIGN(nbytes);
-       if (nbytes > stacknleft) {
-               int blocksize;
-               struct stack_block *sp;
+       int pid;
+       int status;
+       struct job *jp;
+       struct job *thisjob;
+       int state;
 
-               blocksize = nbytes;
-               if (blocksize < MINSIZE)
-                       blocksize = MINSIZE;
-               INTOFF;
-               sp = xmalloc(sizeof(struct stack_block) - MINSIZE + blocksize);
-               sp->prev = stackp;
-               stacknxt = sp->space;
-               stacknleft = blocksize;
-               stackp = sp;
-               INTON;
+       TRACE(("dowait(%d) called\n", block));
+       pid = waitproc(block, &status);
+       TRACE(("wait returns pid %d, status=%d\n", pid, status));
+       if (pid <= 0)
+               return pid;
+       INTOFF;
+       thisjob = NULL;
+       for (jp = curjob; jp; jp = jp->prev_job) {
+               struct procstat *sp;
+               struct procstat *spend;
+               if (jp->state == JOBDONE)
+                       continue;
+               state = JOBDONE;
+               spend = jp->ps + jp->nprocs;
+               sp = jp->ps;
+               do {
+                       if (sp->pid == pid) {
+                               TRACE(("Job %d: changing status of proc %d from 0x%x to 0x%x\n", jobno(jp), pid, sp->status, status));
+                               sp->status = status;
+                               thisjob = jp;
+                       }
+                       if (sp->status == -1)
+                               state = JOBRUNNING;
+#if JOBS
+                       if (state == JOBRUNNING)
+                               continue;
+                       if (WIFSTOPPED(sp->status)) {
+                               jp->stopstatus = sp->status;
+                               state = JOBSTOPPED;
+                       }
+#endif
+               } while (++sp < spend);
+               if (thisjob)
+                       goto gotjob;
        }
-       p = stacknxt;
-       stacknxt += nbytes;
-       stacknleft -= nbytes;
-       return p;
-}
+#if JOBS
+       if (!WIFSTOPPED(status))
+#endif
 
+               jobless--;
+       goto out;
 
-static void
-stunalloc(pointer p)
-{
-#ifdef DEBUG
-       if (p == NULL) {                /*DEBUG */
-               write(2, "stunalloc\n", 10);
-               abort();
-       }
+gotjob:
+       if (state != JOBRUNNING) {
+               thisjob->changed = 1;
+
+               if (thisjob->state != state) {
+                       TRACE(("Job %d: changing state from %d to %d\n", jobno(thisjob), thisjob->state, state));
+                       thisjob->state = state;
+#if JOBS
+                       if (state == JOBSTOPPED) {
+                               set_curjob(thisjob, CUR_STOPPED);
+                       }
 #endif
-       if (!(stacknxt >= (char *)p && (char *)p >= stackp->space)) {
-               p = stackp->space;
+               }
        }
-       stacknleft += stacknxt - (char *)p;
-       stacknxt = p;
-}
-
-
-static void
-setstackmark(struct stackmark *mark)
-{
-       mark->stackp = stackp;
-       mark->stacknxt = stacknxt;
-       mark->stacknleft = stacknleft;
-       mark->marknext = markp;
-       markp = mark;
-}
 
+out:
+       INTON;
 
-static void
-popstackmark(struct stackmark *mark)
-{
-       struct stack_block *sp;
+       if (thisjob && thisjob == job) {
+               char s[48 + 1];
+               int len;
 
-       INTOFF;
-       markp = mark->marknext;
-       while (stackp != mark->stackp) {
-               sp = stackp;
-               stackp = sp->prev;
-               ckfree(sp);
+               len = sprint_status(s, status, 1);
+               if (len) {
+                       s[len] = '\n';
+                       s[len + 1] = 0;
+                       out2str(s);
+               }
        }
-       stacknxt = mark->stacknxt;
-       stacknleft = mark->stacknleft;
-       INTON;
+       return pid;
 }
 
 
 /*
- * When the parser reads in a string, it wants to stick the string on the
- * stack and only adjust the stack pointer when it knows how big the
- * string is.  Stackblock (defined in stack.h) returns a pointer to a block
- * of space on top of the stack and stackblocklen returns the length of
- * this block.  Growstackblock will grow this space by at least one byte,
- * possibly moving it (like realloc).  Grabstackblock actually allocates the
- * part of the block that has been used.
+ * return 1 if there are stopped jobs, otherwise 0
  */
 
-static void
-growstackblock(void) {
-       char *p;
-       int newlen = ALIGN(stacknleft * 2 + 100);
-       char *oldspace = stacknxt;
-       int oldlen = stacknleft;
-       struct stack_block *sp;
-       struct stack_block *oldstackp;
+int
+stoppedjobs(void)
+{
+       struct job *jp;
+       int retval;
 
-       if (stacknxt == stackp->space && stackp != &stackbase) {
-               INTOFF;
-               oldstackp = stackp;
-               sp = stackp;
-               stackp = sp->prev;
-               sp = xrealloc((pointer)sp, sizeof(struct stack_block) - MINSIZE + newlen);
-               sp->prev = stackp;
-               stackp = sp;
-               stacknxt = sp->space;
-               stacknleft = newlen;
-               {
-                 /* Stack marks pointing to the start of the old block
-                  * must be relocated to point to the new block
-                  */
-                 struct stackmark *xmark;
-                 xmark = markp;
-                 while (xmark != NULL && xmark->stackp == oldstackp) {
-                   xmark->stackp = stackp;
-                   xmark->stacknxt = stacknxt;
-                   xmark->stacknleft = stacknleft;
-                   xmark = xmark->marknext;
-                 }
-               }
-               INTON;
-       } else {
-               p = stalloc(newlen);
-               memcpy(p, oldspace, oldlen);
-               stacknxt = p;                   /* free the space */
-               stacknleft += newlen;           /* we just allocated */
+       retval = 0;
+       if (job_warning)
+               goto out;
+       jp = curjob;
+       if (jp && jp->state == JOBSTOPPED) {
+               out2str("You have stopped jobs.\n");
+               job_warning = 2;
+               retval++;
        }
-}
 
-
-
-static inline void
-grabstackblock(int len)
-{
-       len = ALIGN(len);
-       stacknxt += len;
-       stacknleft -= len;
+out:
+       return retval;
 }
 
-
-
 /*
- * The following routines are somewhat easier to use that the above.
- * The user declares a variable of type STACKSTR, which may be declared
- * to be a register.  The macro STARTSTACKSTR initializes things.  Then
- * the user uses the macro STPUTC to add characters to the string.  In
- * effect, STPUTC(c, p) is the same as *p++ = c except that the stack is
- * grown as necessary.  When the user is done, she can just leave the
- * string there and refer to it using stackblock().  Or she can allocate
- * the space for it using grabstackstr().  If it is necessary to allow
- * someone else to use the stack temporarily and then continue to grow
- * the string, the user should use grabstack to allocate the space, and
- * then call ungrabstr(p) to return to the previous mode of operation.
- *
- * USTPUTC is like STPUTC except that it doesn't check for overflow.
- * CHECKSTACKSPACE can be called before USTPUTC to ensure that there
- * is space for at least one character.
+ * Return a string identifying a command (to be printed by the
+ * jobs command).
  */
 
+#if JOBS
+static char *cmdnextc;
 
 static char *
-growstackstr(void) {
-       int len = stackblocksize();
-       if (herefd >= 0 && len >= 1024) {
-               xwrite(herefd, stackblock(), len);
-               sstrnleft = len - 1;
-               return stackblock();
-       }
-       growstackblock();
-       sstrnleft = stackblocksize() - len - 1;
-       return stackblock() + len;
-}
-
-
-/*
- * Called from CHECKSTRSPACE.
- */
+commandtext(union node *n)
+{
+       char *name;
 
-static char *
-makestrspace(size_t newlen) {
-       int len = stackblocksize() - sstrnleft;
-       do {
-               growstackblock();
-               sstrnleft = stackblocksize() - len;
-       } while (sstrnleft < newlen);
-       return stackblock() + len;
+       STARTSTACKSTR(cmdnextc);
+       cmdtxt(n);
+       name = stackblock();
+       TRACE(("commandtext: name %p, end %p\n\t\"%s\"\n",
+               name, cmdnextc, cmdnextc));
+       return savestr(name);
 }
 
-
-
 static void
-ungrabstackstr(char *s, char *p)
+cmdtxt(union node *n)
 {
-       stacknleft += stacknxt - s;
-       stacknxt = s;
-       sstrnleft = stacknleft - (p - s);
-}
-/*
- * Miscelaneous builtins.
- */
-
-
-#undef rflag
+       union node *np;
+       struct nodelist *lp;
+       const char *p;
+       char s[2];
 
-#if !defined(__GLIBC__) || __GLIBC__ == 2 && __GLIBC_MINOR__ < 1
-typedef long rlim_t;
+       if (!n)
+               return;
+       switch (n->type) {
+       default:
+#if DEBUG
+               abort();
 #endif
-
-
-
-/*
- * The read builtin.  The -e option causes backslashes to escape the
- * following character.
- *
- * This uses unbuffered input, which may be avoidable in some cases.
- */
-
-static int
-readcmd(int argc, char **argv)
-{
-       char **ap;
-       int backslash;
-       char c;
-       int rflag;
-       char *prompt;
-       const char *ifs;
-       char *p;
-       int startword;
-       int status;
-       int i;
-
-       rflag = 0;
-       prompt = NULL;
-       while ((i = nextopt("p:r")) != '\0') {
-               if (i == 'p')
-                       prompt = optionarg;
-               else
-                       rflag = 1;
+       case NPIPE:
+               lp = n->npipe.cmdlist;
+               for (;;) {
+                       cmdtxt(lp->n);
+                       lp = lp->next;
+                       if (!lp)
+                               break;
+                       cmdputs(" | ");
+               }
+               break;
+       case NSEMI:
+               p = "; ";
+               goto binop;
+       case NAND:
+               p = " && ";
+               goto binop;
+       case NOR:
+               p = " || ";
+binop:
+               cmdtxt(n->nbinary.ch1);
+               cmdputs(p);
+               n = n->nbinary.ch2;
+               goto donode;
+       case NREDIR:
+       case NBACKGND:
+               n = n->nredir.n;
+               goto donode;
+       case NNOT:
+               cmdputs("!");
+               n = n->nnot.com;
+donode:
+               cmdtxt(n);
+               break;
+       case NIF:
+               cmdputs("if ");
+               cmdtxt(n->nif.test);
+               cmdputs("; then ");
+               n = n->nif.ifpart;
+               if (n->nif.elsepart) {
+                       cmdtxt(n);
+                       cmdputs("; else ");
+                       n = n->nif.elsepart;
+               }
+               p = "; fi";
+               goto dotail;
+       case NSUBSHELL:
+               cmdputs("(");
+               n = n->nredir.n;
+               p = ")";
+               goto dotail;
+       case NWHILE:
+               p = "while ";
+               goto until;
+       case NUNTIL:
+               p = "until ";
+until:
+               cmdputs(p);
+               cmdtxt(n->nbinary.ch1);
+               n = n->nbinary.ch2;
+               p = "; done";
+dodo:
+               cmdputs("; do ");
+dotail:
+               cmdtxt(n);
+               goto dotail2;
+       case NFOR:
+               cmdputs("for ");
+               cmdputs(n->nfor.var);
+               cmdputs(" in ");
+               cmdlist(n->nfor.args, 1);
+               n = n->nfor.body;
+               p = "; done";
+               goto dodo;
+       case NDEFUN:
+               cmdputs(n->narg.text);
+               p = "() { ... }";
+               goto dotail2;
+       case NCMD:
+               cmdlist(n->ncmd.args, 1);
+               cmdlist(n->ncmd.redirect, 0);
+               break;
+       case NARG:
+               p = n->narg.text;
+dotail2:
+               cmdputs(p);
+               break;
+       case NHERE:
+       case NXHERE:
+               p = "<<...";
+               goto dotail2;
+       case NCASE:
+               cmdputs("case ");
+               cmdputs(n->ncase.expr->narg.text);
+               cmdputs(" in ");
+               for (np = n->ncase.cases; np; np = np->nclist.next) {
+                       cmdtxt(np->nclist.pattern);
+                       cmdputs(") ");
+                       cmdtxt(np->nclist.body);
+                       cmdputs(";; ");
+               }
+               p = "esac";
+               goto dotail2;
+       case NTO:
+               p = ">";
+               goto redir;
+       case NCLOBBER:
+               p = ">|";
+               goto redir;
+       case NAPPEND:
+               p = ">>";
+               goto redir;
+       case NTOFD:
+               p = ">&";
+               goto redir;
+       case NFROM:
+               p = "<";
+               goto redir;
+       case NFROMFD:
+               p = "<&";
+               goto redir;
+       case NFROMTO:
+               p = "<>";
+redir:
+               s[0] = n->nfile.fd + '0';
+               s[1] = '\0';
+               cmdputs(s);
+               cmdputs(p);
+               if (n->type == NTOFD || n->type == NFROMFD) {
+                       s[0] = n->ndup.dupfd + '0';
+                       p = s;
+                       goto dotail2;
+               } else {
+                       n = n->nfile.fname;
+                       goto donode;
+               }
        }
-       if (prompt && isatty(0)) {
-               out2str(prompt);     /* read without cmdedit */
-               flushall();
+}
+
+static void
+cmdlist(union node *np, int sep)
+{
+       for (; np; np = np->narg.next) {
+               if (!sep)
+                       cmdputs(spcstr);
+               cmdtxt(np);
+               if (sep && np->narg.next)
+                       cmdputs(spcstr);
        }
-       if (*(ap = argptr) == NULL)
-               error("arg count");
-       if ((ifs = bltinlookup("IFS")) == NULL)
-               ifs = defifs;
-       status = 0;
-       startword = 1;
-       backslash = 0;
-       STARTSTACKSTR(p);
-       for (;;) {
-               if (read(0, &c, 1) != 1) {
-                       status = 1;
+}
+
+static void
+cmdputs(const char *s)
+{
+       const char *p, *str;
+       char c, cc[2] = " ";
+       char *nextc;
+       int subtype = 0;
+       int quoted = 0;
+       static const char vstype[VSTYPE + 1][4] = {
+               "", "}", "-", "+", "?", "=",
+               "%", "%%", "#", "##"
+       };
+       nextc = makestrspace((strlen(s) + 1) * 8, cmdnextc);
+       p = s;
+       while ((c = *p++) != 0) {
+               str = 0;
+               switch (c) {
+               case CTLESC:
+                       c = *p++;
                        break;
-               }
-               if (c == '\0')
-                       continue;
-               if (backslash) {
-                       backslash = 0;
-                       if (c != '\n')
-                               STPUTC(c, p);
-                       continue;
-               }
-               if (!rflag && c == '\\') {
-                       backslash++;
-                       continue;
-               }
-               if (c == '\n')
+               case CTLVAR:
+                       subtype = *p++;
+                       if ((subtype & VSTYPE) == VSLENGTH)
+                               str = "${#";
+                       else
+                               str = "${";
+                       if (!(subtype & VSQUOTE) != !(quoted & 1)) {
+                               quoted ^= 1;
+                               c = '"';
+                       } else
+                               goto dostr;
                        break;
-               if (startword && *ifs == ' ' && strchr(ifs, c)) {
-                       continue;
-               }
-               startword = 0;
-               if (backslash && c == '\\') {
-                       if (read(0, &c, 1) != 1) {
-                               status = 1;
+               case CTLENDVAR:
+                       str = "\"}" + !(quoted & 1);
+                       quoted >>= 1;
+                       subtype = 0;
+                       goto dostr;
+               case CTLBACKQ:
+                       str = "$(...)";
+                       goto dostr;
+               case CTLBACKQ+CTLQUOTE:
+                       str = "\"$(...)\"";
+                       goto dostr;
+#ifdef CONFIG_ASH_MATH_SUPPORT
+               case CTLARI:
+                       str = "$((";
+                       goto dostr;
+               case CTLENDARI:
+                       str = "))";
+                       goto dostr;
+#endif
+               case CTLQUOTEMARK:
+                       quoted ^= 1;
+                       c = '"';
+                       break;
+               case '=':
+                       if (subtype == 0)
                                break;
-                       }
-                       STPUTC(c, p);
-               } else if (ap[1] != NULL && strchr(ifs, c) != NULL) {
-                       STACKSTRNUL(p);
-                       setvar(*ap, stackblock(), 0);
-                       ap++;
-                       startword = 1;
-                       STARTSTACKSTR(p);
-               } else {
-                       STPUTC(c, p);
+                       if ((subtype & VSTYPE) != VSNORMAL)
+                               quoted <<= 1;
+                       str = vstype[subtype & VSTYPE];
+                       if (subtype & VSNUL)
+                               c = ':';
+                       else
+                               goto checkstr;
+                       break;
+               case '\'':
+               case '\\':
+               case '"':
+               case '$':
+                       /* These can only happen inside quotes */
+                       cc[0] = c;
+                       str = cc;
+                       c = '\\';
+                       break;
+               default:
+                       break;
+               }
+               USTPUTC(c, nextc);
+checkstr:
+               if (!str)
+                       continue;
+dostr:
+               while ((c = *str++)) {
+                       USTPUTC(c, nextc);
                }
        }
-       STACKSTRNUL(p);
-       /* Remove trailing blanks */
-       while (stackblock() <= --p && strchr(ifs, *p) != NULL)
-               *p = '\0';
-       setvar(*ap, stackblock(), 0);
-       while (*++ap != NULL)
-               setvar(*ap, nullstr, 0);
-       return status;
+       if (quoted & 1) {
+               USTPUTC('"', nextc);
+       }
+       *nextc = 0;
+       cmdnextc = nextc;
 }
 
 
-
-static int
-umaskcmd(int argc, char **argv)
+static void
+showpipe(struct job *jp, FILE *out)
 {
-       static const char permuser[3] = "ugo";
-       static const char permmode[3] = "rwx";
-       static const short int permmask[] = {
-               S_IRUSR, S_IWUSR, S_IXUSR,
-               S_IRGRP, S_IWGRP, S_IXGRP,
-               S_IROTH, S_IWOTH, S_IXOTH
-       };
+       struct procstat *sp;
+       struct procstat *spend;
 
-       char *ap;
-       mode_t mask;
-       int i;
-       int symbolic_mode = 0;
+       spend = jp->ps + jp->nprocs;
+       for (sp = jp->ps + 1; sp < spend; sp++)
+               fprintf(out, " | %s", sp->cmd);
+       outcslow('\n', out);
+       flushall();
+}
 
-       while (nextopt("S") != '\0') {
-               symbolic_mode = 1;
-       }
+static void
+xtcsetpgrp(int fd, pid_t pgrp)
+{
+       if (tcsetpgrp(fd, pgrp))
+               sh_error("Cannot set tty process group (%m)");
+}
+#endif /* JOBS */
 
-       INTOFF;
-       mask = umask(0);
-       umask(mask);
-       INTON;
+static int
+getstatus(struct job *job) {
+       int status;
+       int retval;
 
-       if ((ap = *argptr) == NULL) {
-               if (symbolic_mode) {
-                       char buf[18];
-                       char *p = buf;
-                       for (i=0 ; i<3 ; i++) {
-                               int j;
-                               *p++ = permuser[i];
-                               *p++ = '=';
-                               for (j=0 ; j<3 ; j++) {
-                                       if ((mask & permmask[3*i+j]) == 0) {
-                                               *p++ = permmode[j];
-                                       }
-                               }
-                               *p++ = ',';
-                       }
-                       *--p = 0;
-                       puts(buf);
-               } else {
-                       printf("%.4o\n", mask);
-               }
-       } else {
-               if (is_digit((unsigned char)*ap)) {
-                       mask = 0;
-                       do {
-                               if (*ap >= '8' || *ap < '0')
-                                       error("Illegal number: %s", argv[1]);
-                               mask = (mask << 3) + (*ap - '0');
-                       } while (*++ap != '\0');
-                       umask(mask);
-               } else {
-                       mask = ~mask & 0777;
-                       if (! parse_mode(ap, &mask)) {
-                               error("Illegal mode: %s", ap);
-                       }
-                       umask(~mask & 0777);
+       status = job->ps[job->nprocs - 1].status;
+       retval = WEXITSTATUS(status);
+       if (!WIFEXITED(status)) {
+#if JOBS
+               retval = WSTOPSIG(status);
+               if (!WIFSTOPPED(status))
+#endif
+               {
+                       /* XXX: limits number of signals */
+                       retval = WTERMSIG(status);
+#if JOBS
+                       if (retval == SIGINT)
+                               job->sigint = 1;
+#endif
                }
+               retval += 128;
        }
-       return 0;
+       TRACE(("getstatus: job %d, nproc %d, status %x, retval %x\n",
+               jobno(job), job->nprocs, status, retval));
+       return retval;
 }
 
+#ifdef CONFIG_ASH_MAIL
+/*      mail.c       */
+
 /*
- * ulimit builtin
- *
- * This code, originally by Doug Gwyn, Doug Kingston, Eric Gisin, and
- * Michael Rendell was ripped from pdksh 5.0.8 and hacked for use with
- * ash by J.T. Conklin.
- *
- * Public domain.
+ * Routines to check for mail.  (Perhaps make part of main.c?)
  */
 
-struct limits {
-       const char *name;
-       short   cmd;
-       short   factor; /* multiply by to get rlim_{cur,max} values */
-};
+#define MAXMBOXES 10
 
-static const struct limits limits[] = {
-#ifdef RLIMIT_CPU
-       { "time(seconds)",             RLIMIT_CPU,        1 },
-#endif
-#ifdef RLIMIT_FSIZE
-       { "file(blocks)",              RLIMIT_FSIZE,    512 },
-#endif
-#ifdef RLIMIT_DATA
-       { "data(kbytes)",              RLIMIT_DATA,    1024 },
-#endif
-#ifdef RLIMIT_STACK
-       { "stack(kbytes)",             RLIMIT_STACK,   1024 },
-#endif
-#ifdef  RLIMIT_CORE
-       { "coredump(blocks)",          RLIMIT_CORE,     512 },
-#endif
-#ifdef RLIMIT_RSS
-       { "memory(kbytes)",            RLIMIT_RSS,     1024 },
-#endif
-#ifdef RLIMIT_MEMLOCK
-       { "locked memory(kbytes)",     RLIMIT_MEMLOCK, 1024 },
-#endif
-#ifdef RLIMIT_NPROC
-       { "process(processes)",        RLIMIT_NPROC,      1 },
-#endif
-#ifdef RLIMIT_NOFILE
-       { "nofiles(descriptors)",      RLIMIT_NOFILE,     1 },
-#endif
-#ifdef RLIMIT_VMEM
-       { "vmemory(kbytes)",           RLIMIT_VMEM,    1024 },
-#endif
-#ifdef RLIMIT_SWAP
-       { "swap(kbytes)",              RLIMIT_SWAP,    1024 },
-#endif
-       { NULL,                         0,                 0 }
-};
+/* times of mailboxes */
+static time_t mailtime[MAXMBOXES];
+/* Set if MAIL or MAILPATH is changed. */
+static int mail_var_path_changed;
 
-static int
-ulimitcmd(int argc, char **argv)
-{
-       static const char unlimited_string[] = "unlimited";
-       int     c;
-       rlim_t val = 0;
-       enum { SOFT = 0x1, HARD = 0x2 }
-                       how = SOFT | HARD;
-       const struct limits     *l;
-       int             set, all = 0;
-       int             optc, what;
-       struct rlimit   limit;
 
-       what = 'f';
 
-       while ((optc = nextopt("HSa"
-#ifdef RLIMIT_CPU
-       "t"
-#endif
-#ifdef RLIMIT_FSIZE
-       "f"
-#endif
-#ifdef RLIMIT_DATA
-       "d"
-#endif
-#ifdef RLIMIT_STACK
-       "s"
+/*
+ * Print appropriate message(s) if mail has arrived.
+ * If mail_var_path_changed is set,
+ * then the value of MAIL has mail_var_path_changed,
+ * so we just update the values.
+ */
+
+static void
+chkmail(void)
+{
+       const char *mpath;
+       char *p;
+       char *q;
+       time_t *mtp;
+       struct stackmark smark;
+       struct stat statb;
+
+       setstackmark(&smark);
+       mpath = mpathset() ? mpathval() : mailval();
+       for (mtp = mailtime; mtp < mailtime + MAXMBOXES; mtp++) {
+               p = padvance(&mpath, nullstr);
+               if (p == NULL)
+                       break;
+               if (*p == '\0')
+                       continue;
+               for (q = p ; *q ; q++);
+#ifdef DEBUG
+               if (q[-1] != '/')
+                       abort();
 #endif
-#ifdef  RLIMIT_CORE
-       "c"
+               q[-1] = '\0';                   /* delete trailing '/' */
+               if (stat(p, &statb) < 0) {
+                       *mtp = 0;
+                       continue;
+               }
+               if (!mail_var_path_changed && statb.st_mtime != *mtp) {
+                       fprintf(
+                               stderr, snlfmt,
+                               pathopt ? pathopt : "you have mail"
+                       );
+               }
+               *mtp = statb.st_mtime;
+       }
+       mail_var_path_changed = 0;
+       popstackmark(&smark);
+}
+
+
+static void
+changemail(const char *val)
+{
+       mail_var_path_changed++;
+}
+
+#endif /* CONFIG_ASH_MAIL */
+
+/*      main.c       */
+
+
+#if PROFILE
+static short profile_buf[16384];
+extern int etext();
 #endif
-#ifdef RLIMIT_RSS
-       "m"
+
+static int isloginsh;
+
+static void read_profile(const char *);
+
+/*
+ * Main routine.  We initialize things, parse the arguments, execute
+ * profiles if we're a login shell, and then call cmdloop to execute
+ * commands.  The setjmp call sets up the location to jump to when an
+ * exception occurs.  When an exception occurs the variable "state"
+ * is used to figure out how far we had gotten.
+ */
+
+int
+ash_main(int argc, char **argv)
+{
+       char *shinit;
+       volatile int state;
+       struct jmploc jmploc;
+       struct stackmark smark;
+
+#ifdef __GLIBC__
+       dash_errno = __errno_location();
 #endif
-#ifdef RLIMIT_MEMLOCK
-       "l"
+
+#if PROFILE
+       monitor(4, etext, profile_buf, sizeof profile_buf, 50);
 #endif
-#ifdef RLIMIT_NPROC
-       "p"
+       state = 0;
+       if (setjmp(jmploc.loc)) {
+               int e;
+               int s;
+
+               reset();
+
+               e = exception;
+               if (e == EXERROR)
+                       exitstatus = 2;
+               s = state;
+               if (e == EXEXIT || s == 0 || iflag == 0 || shlvl)
+                       exitshell();
+
+               if (e == EXINT) {
+                       outcslow('\n', stderr);
+               }
+               popstackmark(&smark);
+               FORCEINTON;                             /* enable interrupts */
+               if (s == 1)
+                       goto state1;
+               else if (s == 2)
+                       goto state2;
+               else if (s == 3)
+                       goto state3;
+               else
+                       goto state4;
+       }
+       handler = &jmploc;
+#ifdef DEBUG
+       opentrace();
+       trputs("Shell args:  ");  trargs(argv);
 #endif
-#ifdef RLIMIT_NOFILE
-       "n"
+       rootpid = getpid();
+
+#ifdef CONFIG_ASH_RANDOM_SUPPORT
+       rseed = rootpid + ((time_t)time((time_t *)0));
 #endif
-#ifdef RLIMIT_VMEM
-       "v"
+       init();
+       setstackmark(&smark);
+       procargs(argc, argv);
+#ifdef CONFIG_FEATURE_COMMAND_SAVEHISTORY
+       if ( iflag ) {
+               const char *hp = lookupvar("HISTFILE");
+
+               if(hp == NULL ) {
+                       hp = lookupvar("HOME");
+                       if(hp != NULL) {
+                               char *defhp = concat_path_file(hp, ".ash_history");
+                               setvar("HISTFILE", defhp, 0);
+                               free(defhp);
+                       }
+               }
+       }
 #endif
-#ifdef RLIMIT_SWAP
-       "w"
+       if (argv[0] && argv[0][0] == '-')
+               isloginsh = 1;
+       if (isloginsh) {
+               state = 1;
+               read_profile("/etc/profile");
+state1:
+               state = 2;
+               read_profile(".profile");
+       }
+state2:
+       state = 3;
+       if (
+#ifndef linux
+               getuid() == geteuid() && getgid() == getegid() &&
 #endif
-                                       )) != '\0') {
-               if (optc == 'H') {
-                       how = HARD;
-               } else if (optc == 'S') {
-                       how = SOFT;
-               } else if (optc == 'a') {
-                       all = 1;
-               } else {
-                       what = optc;
+               iflag
+       ) {
+               if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') {
+                       read_profile(shinit);
                }
        }
+state3:
+       state = 4;
+       if (minusc)
+               evalstring(minusc, 0);
 
-       for (l = limits; l->name; l++) {
-               if(l->name[0] == what)
-                       break;
-               if(l->name[1]=='w' && what=='w')
-                       break;
+       if (sflag || minusc == NULL) {
+#ifdef CONFIG_FEATURE_COMMAND_SAVEHISTORY
+           if ( iflag ) {
+               const char *hp = lookupvar("HISTFILE");
+
+               if(hp != NULL )
+                       load_history ( hp );
+           }
+#endif
+state4: /* XXX ??? - why isn't this before the "if" statement */
+               cmdloop(1);
+       }
+#if PROFILE
+       monitor(0);
+#endif
+#if GPROF
+       {
+               extern void _mcleanup(void);
+               _mcleanup();
        }
+#endif
+       exitshell();
+       /* NOTREACHED */
+}
 
-       set = *argptr ? 1 : 0;
-       if (set) {
-               char *p = *argptr;
 
-               if (all || argptr[1])
-                       error("too many arguments");
-               if (strcmp(p, unlimited_string) == 0)
-                       val = RLIM_INFINITY;
-               else {
-                       val = (rlim_t) 0;
+/*
+ * Read and execute commands.  "Top" is nonzero for the top level command
+ * loop; it turns on prompting if the shell is interactive.
+ */
 
-                       while ((c = *p++) >= '0' && c <= '9')
-                       {
-                               val = (val * 10) + (long)(c - '0');
-                               if (val < (rlim_t) 0)
-                                       break;
-                       }
-                       if (c)
-                               error("bad number");
-                       val *= l->factor;
-               }
-       }
+static int
+cmdloop(int top)
+{
+       union node *n;
+       struct stackmark smark;
+       int inter;
+       int numeof = 0;
 
-       if (all) {
-               for (l = limits; l->name; l++) {
-                       printf("%-20s ", l->name);
-                       getrlimit(l->cmd, &limit);
-               OUTPUT_LIMIT:
-                       if (how & SOFT)
-                               val = limit.rlim_cur;
-                       else if (how & HARD)
-                               val = limit.rlim_max;
-
-                       if (val == RLIM_INFINITY)
-                               puts(unlimited_string);
-                       else
-                       {
-                               val /= l->factor;
-                               printf("%lld\n", (long long) val);
-                       }
-                       if (!all) {
+       TRACE(("cmdloop(%d) called\n", top));
+       for (;;) {
+               int skip;
+
+               setstackmark(&smark);
+#if JOBS
+               if (jobctl)
+                       showjobs(stderr, SHOW_CHANGED);
+#endif
+               inter = 0;
+               if (iflag && top) {
+                       inter++;
+#ifdef CONFIG_ASH_MAIL
+                       chkmail();
+#endif
+               }
+               n = parsecmd(inter);
+               /* showtree(n); DEBUG */
+               if (n == NEOF) {
+                       if (!top || numeof >= 50)
                                break;
+                       if (!stoppedjobs()) {
+                               if (!Iflag)
+                                       break;
+                               out2str("\nUse \"exit\" to leave shell.\n");
                        }
+                       numeof++;
+               } else if (nflag == 0) {
+                       job_warning = (job_warning == 2) ? 1 : 0;
+                       numeof = 0;
+                       evaltree(n, 0);
                }
-               return 0;
-       }
+               popstackmark(&smark);
+               skip = evalskip;
 
-       if (!set) {
-               goto OUTPUT_LIMIT;
+               if (skip) {
+                       evalskip = 0;
+                       return skip & SKIPEVAL;
+               }
        }
 
-       getrlimit(l->cmd, &limit);
-       if (how & HARD)
-               limit.rlim_max = val;
-       if (how & SOFT)
-               limit.rlim_cur = val;
-       if (setrlimit(l->cmd, &limit) < 0)
-               error("error setting limit (%m)");
        return 0;
 }
-/*
- * prefix -- see if pfx is a prefix of string.
- */
 
-static int
-prefix(char const *pfx, char const *string)
-{
-       while (*pfx) {
-               if (*pfx++ != *string++)
-                       return 0;
-       }
-       return 1;
-}
 
 /*
- * Return true if s is a string of digits, and save munber in intptr
- * nagative is bad
+ * Read /etc/profile or .profile.  Return on error.
  */
 
-static int
-is_number(const char *p, int *intptr)
+static void
+read_profile(const char *name)
 {
-       int ret = 0;
+       int skip;
 
-       do {
-               if (! is_digit(*p))
-                       return 0;
-               ret *= 10;
-               ret += digit_val(*p);
-               p++;
-       } while (*p != '\0');
+       if (setinputfile(name, INPUT_PUSH_FILE | INPUT_NOFILE_OK) < 0)
+               return;
 
-       *intptr = ret;
-       return 1;
+       skip = cmdloop(0);
+       popfile();
+
+       if (skip)
+               exitshell();
 }
 
+
 /*
- * Convert a string of digits to an integer, printing an error message on
- * failure.
+ * Read a file containing shell functions.
  */
 
-static int
-number(const char *s)
+static void
+readcmdfile(char *name)
 {
-       int i;
-       if (! is_number(s, &i))
-               error("Illegal number: %s", s);
-       return i;
+       setinputfile(name, INPUT_PUSH_FILE);
+       cmdloop(0);
+       popfile();
 }
 
+
 /*
- * Produce a possibly single quoted string suitable as input to the shell.
- * The return string is allocated on the stack.
+ * Take commands from a file.  To be compatible we should do a path
+ * search for the file, which is necessary to find sub-commands.
  */
 
-static char *
-single_quote(const char *s)
+static inline char *
+find_dot_file(char *name)
 {
-       char *p;
-
-       STARTSTACKSTR(p);
-
-       do {
-               char *q = p;
-               size_t len1, len1p, len2, len2p;
-
-               len1 = strcspn(s, "'");
-               len2 = strspn(s + len1, "'");
-
-               len1p = len1 ? len1 + 2 : len1;
-               len2p = len2 + ((len2 < 2) ? len2 : 2);
-
-               CHECKSTRSPACE(len1p + len2p + 1, p);
+       char *fullname;
+       const char *path = pathval();
+       struct stat statb;
 
-               if (len1) {
-                       *p = '\'';
-                       q = p + 1 + len1;
-                       memcpy(p + 1, s, len1);
-                       *q++ = '\'';
-                       s += len1;
-               }
+       /* don't try this for absolute or relative paths */
+       if (strchr(name, '/'))
+               return name;
 
-               if (len2 > 1) {
-                       *q = '"';
-                       q += 1 + len2;
-                       memcpy(q + 1, s, len2);
-                       *q = '"';
-                       s += len2;
-               } else if (len2 == 1) {
-                       *q++ = '\\';
-                       *q = '\'';
-                       s++;
+       while ((fullname = padvance(&path, name)) != NULL) {
+               if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) {
+                       /*
+                        * Don't bother freeing here, since it will
+                        * be freed by the caller.
+                        */
+                       return fullname;
                }
+               stunalloc(fullname);
+       }
 
-               STADJUST(len1p + len2p, p);
-       } while (*s);
+       /* not found in the PATH */
+       sh_error(not_found_msg, name);
+       /* NOTREACHED */
+}
 
-       USTPUTC(0, p);
+static int dotcmd(int argc, char **argv)
+{
+       struct strlist *sp;
+       volatile struct shparam saveparam;
+       int status = 0;
+
+       for (sp = cmdenviron; sp; sp = sp->next)
+               setvareq(xstrdup(sp->text), VSTRFIXED | VTEXTFIXED);
+
+       if (argc >= 2) {        /* That's what SVR2 does */
+               char *fullname;
+
+               fullname = find_dot_file(argv[1]);
+
+               if (argc > 2) {
+                       saveparam = shellparam;
+                       shellparam.malloc = 0;
+                       shellparam.nparam = argc - 2;
+                       shellparam.p = argv + 2;
+               };
+
+               setinputfile(fullname, INPUT_PUSH_FILE);
+               commandname = fullname;
+               cmdloop(0);
+               popfile();
+
+               if (argc > 2) {
+                       freeparam(&shellparam);
+                       shellparam = saveparam;
+               };
+               status = exitstatus;
+       }
+       return status;
+}
+
+
+static int
+exitcmd(int argc, char **argv)
+{
+       if (stoppedjobs())
+               return 0;
+       if (argc > 1)
+               exitstatus = number(argv[1]);
+       exraise(EXEXIT);
+       /* NOTREACHED */
+}
+
+#ifdef CONFIG_ASH_BUILTIN_ECHO
+static int
+echocmd(int argc, char **argv)
+{
+       return bb_echo(argc, argv);
+}
+#endif
 
-       return grabstackstr(p);
+#ifdef CONFIG_ASH_BUILTIN_TEST
+static int
+testcmd(int argc, char **argv)
+{
+       return bb_test(argc, argv);
 }
+#endif
+
+/*      memalloc.c        */
 
 /*
- * Like strdup but works with the ash stack.
+ * Same for malloc, realloc, but returns an error when out of space.
  */
 
-static char *
-sstrdup(const char *p)
+static pointer
+ckrealloc(pointer p, size_t nbytes)
 {
-       size_t len = strlen(p) + 1;
-       return memcpy(stalloc(len), p, len);
+       p = realloc(p, nbytes);
+       if (p == NULL)
+               sh_error(bb_msg_memory_exhausted);
+       return p;
 }
 
+static pointer
+ckmalloc(size_t nbytes)
+{
+       return ckrealloc(NULL, nbytes);
+}
 
 /*
- * Routine for dealing with parsed shell commands.
+ * Make a copy of a string in safe storage.
  */
 
+static char *
+savestr(const char *s)
+{
+       char *p = strdup(s);
+       if (!p)
+               sh_error(bb_msg_memory_exhausted);
+       return p;
+}
 
-static void sizenodelist (const struct nodelist *);
-static struct nodelist *copynodelist (const struct nodelist *);
-static char *nodexstrdup (const char *);
 
-#define CALCSIZE_TABLE
-#define COPYNODE_TABLE
-#if defined(CALCSIZE_TABLE) || defined(COPYNODE_TABLE)
 /*
- * To collect a lot of redundant code in case statements for copynode()
- * and calcsize(), we implement a mini language here.  Each type of node
- * struct has an associated instruction sequence that operates on its
- * members via their offsets.  The instruction are pack in unsigned chars
- * with format   IIDDDDDE   where the bits are
- *   I : part of the instruction opcode, which are
- *       00 : member is a pointer to another node
- *       40 : member is an integer
- *       80 : member is a pointer to a nodelist
- *       CC : member is a pointer to a char string
- *   D : data - the actual offset of the member to operate on in the struct
- *              (since we assume bit 0 is set, it is not shifted)
- *   E : flag signaling end of instruction sequence
+ * Parse trees for commands are allocated in lifo order, so we use a stack
+ * to make this more efficient, and also to avoid all sorts of exception
+ * handling code to handle interrupts in the middle of a parse.
  *
- * WARNING: In order to handle larger offsets for 64bit archs, this code
- *          assumes that no offset can be an odd number and stores the
- *          end-of-instructions flag in bit 0.
- */
-
-#define NODE_INTEGER    0x40
-#define NODE_NODELIST   0x80
-#define NODE_CHARPTR    0xC0
-#define NODE_NOMORE             0x01    /* Note: no offset should be odd (aligned)*/
-#define NODE_MBRMASK    0xC0
-#define NODE_OFFSETMASK 0x3E
-
-static const unsigned char copynode_ops[35] = {
-#define COPYNODE_OPS0   0
-       offsetof(union node, nbinary.ch2),
-       offsetof(union node, nbinary.ch1)|NODE_NOMORE,
-#define COPYNODE_OPS1   (COPYNODE_OPS0 + 2)
-       offsetof(union node, ncmd.redirect),
-       offsetof(union node, ncmd.args),
-       offsetof(union node, ncmd.assign),
-       offsetof(union node, ncmd.backgnd)|NODE_INTEGER|NODE_NOMORE,
-#define COPYNODE_OPS2   (COPYNODE_OPS1 + 4)
-       offsetof(union node, npipe.cmdlist)|NODE_NODELIST,
-       offsetof(union node, npipe.backgnd)|NODE_INTEGER|NODE_NOMORE,
-#define COPYNODE_OPS3   (COPYNODE_OPS2 + 2)
-       offsetof(union node, nredir.redirect),
-       offsetof(union node, nredir.n)|NODE_NOMORE,
-#define COPYNODE_OPS4   (COPYNODE_OPS3 + 2)
-       offsetof(union node, nif.elsepart),
-       offsetof(union node, nif.ifpart),
-       offsetof(union node, nif.test)|NODE_NOMORE,
-#define COPYNODE_OPS5   (COPYNODE_OPS4 + 3)
-       offsetof(union node, nfor.var)|NODE_CHARPTR,
-       offsetof(union node, nfor.body),
-       offsetof(union node, nfor.args)|NODE_NOMORE,
-#define COPYNODE_OPS6   (COPYNODE_OPS5 + 3)
-       offsetof(union node, ncase.cases),
-       offsetof(union node, ncase.expr)|NODE_NOMORE,
-#define COPYNODE_OPS7   (COPYNODE_OPS6 + 2)
-       offsetof(union node, nclist.body),
-       offsetof(union node, nclist.pattern),
-       offsetof(union node, nclist.next)|NODE_NOMORE,
-#define COPYNODE_OPS8   (COPYNODE_OPS7 + 3)
-       offsetof(union node, narg.backquote)|NODE_NODELIST,
-       offsetof(union node, narg.text)|NODE_CHARPTR,
-       offsetof(union node, narg.next)|NODE_NOMORE,
-#define COPYNODE_OPS9   (COPYNODE_OPS8 + 3)
-       offsetof(union node, nfile.fname),
-       offsetof(union node, nfile.fd)|NODE_INTEGER,
-       offsetof(union node, nfile.next)|NODE_NOMORE,
-#define COPYNODE_OPS10   (COPYNODE_OPS9 + 3)
-       offsetof(union node, ndup.vname),
-       offsetof(union node, ndup.dupfd)|NODE_INTEGER,
-       offsetof(union node, ndup.fd)|NODE_INTEGER,
-       offsetof(union node, ndup.next)|NODE_NOMORE,
-#define COPYNODE_OPS11   (COPYNODE_OPS10 + 4)
-       offsetof(union node, nhere.doc),
-       offsetof(union node, nhere.fd)|NODE_INTEGER,
-       offsetof(union node, nhere.next)|NODE_NOMORE,
-#define COPYNODE_OPS12   (COPYNODE_OPS11 + 3)
-       offsetof(union node, nnot.com)|NODE_NOMORE,
-};
+ * The size 504 was chosen because the Ultrix malloc handles that size
+ * well.
+ */
+
+
+static pointer
+stalloc(size_t nbytes)
+{
+       char *p;
+       size_t aligned;
+
+       aligned = SHELL_ALIGN(nbytes);
+       if (aligned > stacknleft) {
+               size_t len;
+               size_t blocksize;
+               struct stack_block *sp;
+
+               blocksize = aligned;
+               if (blocksize < MINSIZE)
+                       blocksize = MINSIZE;
+               len = sizeof(struct stack_block) - MINSIZE + blocksize;
+               if (len < blocksize)
+                       sh_error(bb_msg_memory_exhausted);
+               INTOFF;
+               sp = ckmalloc(len);
+               sp->prev = stackp;
+               stacknxt = sp->space;
+               stacknleft = blocksize;
+               sstrend = stacknxt + blocksize;
+               stackp = sp;
+               INTON;
+       }
+       p = stacknxt;
+       stacknxt += aligned;
+       stacknleft -= aligned;
+       return p;
+}
 
-#if COPYNODE_OPS12 != 34
-#error COPYNODE_OPS12 is incorrect
-#endif
-
-static const unsigned char copynode_ops_index[26] = {
-       COPYNODE_OPS0, /* NSEMI */
-       COPYNODE_OPS1, /* NCMD */
-       COPYNODE_OPS2, /* NPIPE */
-       COPYNODE_OPS3, /* NREDIR */
-       COPYNODE_OPS3, /* NBACKGND */
-       COPYNODE_OPS3, /* NSUBSHELL */
-       COPYNODE_OPS0, /* NAND */
-       COPYNODE_OPS0, /* NOR */
-       COPYNODE_OPS4, /* NIF */
-       COPYNODE_OPS0, /* NWHILE */
-       COPYNODE_OPS0, /* NUNTIL */
-       COPYNODE_OPS5, /* NFOR */
-       COPYNODE_OPS6, /* NCASE */
-       COPYNODE_OPS7, /* NCLIST */
-       COPYNODE_OPS8, /* NDEFUN */
-       COPYNODE_OPS8, /* NARG */
-       COPYNODE_OPS9, /* NTO */
-       COPYNODE_OPS9, /* NFROM */
-       COPYNODE_OPS9, /* NFROMTO */
-       COPYNODE_OPS9, /* NAPPEND */
-       COPYNODE_OPS9, /* NTOOV */
-       COPYNODE_OPS10, /* NTOFD */
-       COPYNODE_OPS10, /* NFROMFD */
-       COPYNODE_OPS11, /* NHERE */
-       COPYNODE_OPS11, /* NXHERE */
-       COPYNODE_OPS12, /* NNOT */
-};
 
-#if NODE_CHARPTR != NODE_MBRMASK
-#error NODE_CHARPTR != NODE_MBRMASK!!!
+void
+stunalloc(pointer p)
+{
+#ifdef DEBUG
+       if (!p || (stacknxt < (char *)p) || ((char *)p < stackp->space)) {
+               write(2, "stunalloc\n", 10);
+               abort();
+       }
 #endif
-#endif /* defined(CALCSIZE_TABLE) || defined(COPYNODE_TABLE) */
+       stacknleft += stacknxt - (char *)p;
+       stacknxt = p;
+}
 
-#ifdef COPYNODE_TABLE
-static union node *
-copynode(const union node *n)
+
+void
+setstackmark(struct stackmark *mark)
 {
-      union node *new;
-         const unsigned char *p;
+       mark->stackp = stackp;
+       mark->stacknxt = stacknxt;
+       mark->stacknleft = stacknleft;
+       mark->marknext = markp;
+       markp = mark;
+}
 
-      if (n == NULL) {
-          return NULL;
-         }
-      new = funcblock;
-      new->type = n->type;
-      funcblock = (char *) funcblock + (int) nodesize[n->type];
-         p = copynode_ops + (int) copynode_ops_index[n->type];
-         do {
-                 char *nn = ((char *) new) + ((int)(*p & NODE_OFFSETMASK));
-                 const char *no = ((const char *) n) + ((int)(*p & NODE_OFFSETMASK));
-
-                 if (!(*p & NODE_MBRMASK)) { /* standard node */
-                         *((union node **)nn) = copynode(*((const union node **) no));
-                 } else if ((*p & NODE_MBRMASK) == NODE_CHARPTR) { /* string */
-                         *((const char **)nn) = nodexstrdup(*((const char **)no));
-                 } else if (*p & NODE_NODELIST) { /* nodelist */
-                         *((struct nodelist **)nn)
-                                 = copynodelist(*((const struct nodelist **) no));
-                 } else {                              /* integer */
-                         *((int *) nn) = *((int *) no);
-                 }
-         } while (!(*p++ & NODE_NOMORE));
-      return new;
-}
-#else  /* COPYNODE_TABLE */
-static union node *
-copynode(const union node *n)
+
+void
+popstackmark(struct stackmark *mark)
 {
-      union node *new;
+       struct stack_block *sp;
 
-      if (n == NULL)
-        return NULL;
-      new = funcblock;
-      funcblock = (char *) funcblock + nodesize[n->type];
-      switch (n->type) {
-      case NSEMI:
-      case NAND:
-      case NOR:
-      case NWHILE:
-      case NUNTIL:
-           new->nbinary.ch2 = copynode(n->nbinary.ch2);
-           new->nbinary.ch1 = copynode(n->nbinary.ch1);
-           break;
-      case NCMD:
-           new->ncmd.redirect = copynode(n->ncmd.redirect);
-           new->ncmd.args = copynode(n->ncmd.args);
-           new->ncmd.assign = copynode(n->ncmd.assign);
-           new->ncmd.backgnd = n->ncmd.backgnd;
-           break;
-      case NPIPE:
-           new->npipe.cmdlist = copynodelist(n->npipe.cmdlist);
-           new->npipe.backgnd = n->npipe.backgnd;
-           break;
-      case NREDIR:
-      case NBACKGND:
-      case NSUBSHELL:
-           new->nredir.redirect = copynode(n->nredir.redirect);
-           new->nredir.n = copynode(n->nredir.n);
-           break;
-      case NIF:
-           new->nif.elsepart = copynode(n->nif.elsepart);
-           new->nif.ifpart = copynode(n->nif.ifpart);
-           new->nif.test = copynode(n->nif.test);
-           break;
-      case NFOR:
-           new->nfor.var = nodexstrdup(n->nfor.var);
-           new->nfor.body = copynode(n->nfor.body);
-           new->nfor.args = copynode(n->nfor.args);
-           break;
-      case NCASE:
-           new->ncase.cases = copynode(n->ncase.cases);
-           new->ncase.expr = copynode(n->ncase.expr);
-           break;
-      case NCLIST:
-           new->nclist.body = copynode(n->nclist.body);
-           new->nclist.pattern = copynode(n->nclist.pattern);
-           new->nclist.next = copynode(n->nclist.next);
-           break;
-      case NDEFUN:
-      case NARG:
-           new->narg.backquote = copynodelist(n->narg.backquote);
-           new->narg.text = nodexstrdup(n->narg.text);
-           new->narg.next = copynode(n->narg.next);
-           break;
-      case NTO:
-      case NFROM:
-      case NFROMTO:
-      case NAPPEND:
-      case NTOOV:
-           new->nfile.fname = copynode(n->nfile.fname);
-           new->nfile.fd = n->nfile.fd;
-           new->nfile.next = copynode(n->nfile.next);
-           break;
-      case NTOFD:
-      case NFROMFD:
-           new->ndup.vname = copynode(n->ndup.vname);
-           new->ndup.dupfd = n->ndup.dupfd;
-           new->ndup.fd = n->ndup.fd;
-           new->ndup.next = copynode(n->ndup.next);
-           break;
-      case NHERE:
-      case NXHERE:
-           new->nhere.doc = copynode(n->nhere.doc);
-           new->nhere.fd = n->nhere.fd;
-           new->nhere.next = copynode(n->nhere.next);
-           break;
-      case NNOT:
-           new->nnot.com = copynode(n->nnot.com);
-           break;
-      };
-      new->type = n->type;
-      return new;
+       INTOFF;
+       markp = mark->marknext;
+       while (stackp != mark->stackp) {
+               sp = stackp;
+               stackp = sp->prev;
+               ckfree(sp);
+       }
+       stacknxt = mark->stacknxt;
+       stacknleft = mark->stacknleft;
+       sstrend = mark->stacknxt + mark->stacknleft;
+       INTON;
 }
-#endif /* COPYNODE_TABLE */
 
-#ifdef CALCSIZE_TABLE
-static void
-calcsize(const union node *n)
+
+/*
+ * When the parser reads in a string, it wants to stick the string on the
+ * stack and only adjust the stack pointer when it knows how big the
+ * string is.  Stackblock (defined in stack.h) returns a pointer to a block
+ * of space on top of the stack and stackblocklen returns the length of
+ * this block.  Growstackblock will grow this space by at least one byte,
+ * possibly moving it (like realloc).  Grabstackblock actually allocates the
+ * part of the block that has been used.
+ */
+
+void
+growstackblock(void)
 {
-         const unsigned char *p;
+       size_t newlen;
 
-      if (n == NULL)
-           return;
-      funcblocksize += (int) nodesize[n->type];
-
-         p = copynode_ops + (int) copynode_ops_index[n->type];
-         do {
-                 const char *no = ((const char *) n) + ((int)(*p & NODE_OFFSETMASK));
-
-                 if (!(*p & NODE_MBRMASK)) { /* standard node */
-                         calcsize(*((const union node **) no));
-                 } else if ((*p & NODE_MBRMASK) == NODE_CHARPTR) { /* string */
-                         funcstringsize += strlen(*((const char **)no)) + 1;
-                 } else if (*p & NODE_NODELIST) { /* nodelist */
-                         sizenodelist(*((const struct nodelist **) no));
-                 }     /* else integer -- ignore */
-         } while (!(*p++ & NODE_NOMORE));
-}
-#else  /* CALCSIZE_TABLE */
-static void
-calcsize(const union node *n)
+       newlen = stacknleft * 2;
+       if (newlen < stacknleft)
+               sh_error(bb_msg_memory_exhausted);
+       if (newlen < 128)
+               newlen += 128;
+
+       if (stacknxt == stackp->space && stackp != &stackbase) {
+               struct stack_block *oldstackp;
+               struct stackmark *xmark;
+               struct stack_block *sp;
+               struct stack_block *prevstackp;
+               size_t grosslen;
+
+               INTOFF;
+               oldstackp = stackp;
+               sp = stackp;
+               prevstackp = sp->prev;
+               grosslen = newlen + sizeof(struct stack_block) - MINSIZE;
+               sp = ckrealloc((pointer)sp, grosslen);
+               sp->prev = prevstackp;
+               stackp = sp;
+               stacknxt = sp->space;
+               stacknleft = newlen;
+               sstrend = sp->space + newlen;
+
+               /*
+                * Stack marks pointing to the start of the old block
+                * must be relocated to point to the new block
+                */
+               xmark = markp;
+               while (xmark != NULL && xmark->stackp == oldstackp) {
+                       xmark->stackp = stackp;
+                       xmark->stacknxt = stacknxt;
+                       xmark->stacknleft = stacknleft;
+                       xmark = xmark->marknext;
+               }
+               INTON;
+       } else {
+               char *oldspace = stacknxt;
+               int oldlen = stacknleft;
+               char *p = stalloc(newlen);
+
+               /* free the space we just allocated */
+               stacknxt = memcpy(p, oldspace, oldlen);
+               stacknleft += newlen;
+       }
+}
+
+static inline void
+grabstackblock(size_t len)
 {
-      if (n == NULL)
-           return;
-      funcblocksize += nodesize[n->type];
-      switch (n->type) {
-      case NSEMI:
-      case NAND:
-      case NOR:
-      case NWHILE:
-      case NUNTIL:
-           calcsize(n->nbinary.ch2);
-           calcsize(n->nbinary.ch1);
-           break;
+       len = SHELL_ALIGN(len);
+       stacknxt += len;
+       stacknleft -= len;
+}
+
+/*
+ * The following routines are somewhat easier to use than the above.
+ * The user declares a variable of type STACKSTR, which may be declared
+ * to be a register.  The macro STARTSTACKSTR initializes things.  Then
+ * the user uses the macro STPUTC to add characters to the string.  In
+ * effect, STPUTC(c, p) is the same as *p++ = c except that the stack is
+ * grown as necessary.  When the user is done, she can just leave the
+ * string there and refer to it using stackblock().  Or she can allocate
+ * the space for it using grabstackstr().  If it is necessary to allow
+ * someone else to use the stack temporarily and then continue to grow
+ * the string, the user should use grabstack to allocate the space, and
+ * then call ungrabstr(p) to return to the previous mode of operation.
+ *
+ * USTPUTC is like STPUTC except that it doesn't check for overflow.
+ * CHECKSTACKSPACE can be called before USTPUTC to ensure that there
+ * is space for at least one character.
+ */
+
+void *
+growstackstr(void)
+{
+       size_t len = stackblocksize();
+       if (herefd >= 0 && len >= 1024) {
+               full_write(herefd, stackblock(), len);
+               return stackblock();
+       }
+       growstackblock();
+       return stackblock() + len;
+}
+
+/*
+ * Called from CHECKSTRSPACE.
+ */
+
+char *
+makestrspace(size_t newlen, char *p)
+{
+       size_t len = p - stacknxt;
+       size_t size = stackblocksize();
+
+       for (;;) {
+               size_t nleft;
+
+               size = stackblocksize();
+               nleft = size - len;
+               if (nleft >= newlen)
+                       break;
+               growstackblock();
+       }
+       return stackblock() + len;
+}
+
+char *
+stnputs(const char *s, size_t n, char *p)
+{
+       p = makestrspace(n, p);
+       p = mempcpy(p, s, n);
+       return p;
+}
+
+char *
+stputs(const char *s, char *p)
+{
+       return stnputs(s, strlen(s), p);
+}
+
+/*      mystring.c   */
+
+/*
+ * String functions.
+ *
+ *      number(s)               Convert a string of digits to an integer.
+ *      is_number(s)            Return true if s is a string of digits.
+ */
+
+/*
+ * prefix -- see if pfx is a prefix of string.
+ */
+
+char *
+prefix(const char *string, const char *pfx)
+{
+       while (*pfx) {
+               if (*pfx++ != *string++)
+                       return 0;
+       }
+       return (char *) string;
+}
+
+
+/*
+ * Convert a string of digits to an integer, printing an error message on
+ * failure.
+ */
+
+int
+number(const char *s)
+{
+
+       if (! is_number(s))
+               sh_error(illnum, s);
+       return atoi(s);
+}
+
+
+/*
+ * Check for a valid number.  This should be elsewhere.
+ */
+
+int
+is_number(const char *p)
+{
+       do {
+               if (! is_digit(*p))
+                       return 0;
+       } while (*++p != '\0');
+       return 1;
+}
+
+
+/*
+ * Produce a possibly single quoted string suitable as input to the shell.
+ * The return string is allocated on the stack.
+ */
+
+char *
+single_quote(const char *s) {
+       char *p;
+
+       STARTSTACKSTR(p);
+
+       do {
+               char *q;
+               size_t len;
+
+               len = strchrnul(s, '\'') - s;
+
+               q = p = makestrspace(len + 3, p);
+
+               *q++ = '\'';
+               q = mempcpy(q, s, len);
+               *q++ = '\'';
+               s += len;
+
+               STADJUST(q - p, p);
+
+               len = strspn(s, "'");
+               if (!len)
+                       break;
+
+               q = p = makestrspace(len + 3, p);
+
+               *q++ = '"';
+               q = mempcpy(q, s, len);
+               *q++ = '"';
+               s += len;
+
+               STADJUST(q - p, p);
+       } while (*s);
+
+       USTPUTC(0, p);
+
+       return stackblock();
+}
+
+/*
+ * Like strdup but works with the ash stack.
+ */
+
+char *
+sstrdup(const char *p)
+{
+       size_t len = strlen(p) + 1;
+       return memcpy(stalloc(len), p, len);
+}
+
+
+static void
+calcsize(union node *n)
+{
+      if (n == NULL)
+           return;
+      funcblocksize += nodesize[n->type];
+      switch (n->type) {
       case NCMD:
            calcsize(n->ncmd.redirect);
            calcsize(n->ncmd.args);
@@ -8731,6 +8553,14 @@ calcsize(const union node *n)
            calcsize(n->nredir.redirect);
            calcsize(n->nredir.n);
            break;
+      case NAND:
+      case NOR:
+      case NSEMI:
+      case NWHILE:
+      case NUNTIL:
+           calcsize(n->nbinary.ch2);
+           calcsize(n->nbinary.ch1);
+           break;
       case NIF:
            calcsize(n->nif.elsepart);
            calcsize(n->nif.ifpart);
@@ -8757,10 +8587,10 @@ calcsize(const union node *n)
            calcsize(n->narg.next);
            break;
       case NTO:
+      case NCLOBBER:
       case NFROM:
       case NFROMTO:
       case NAPPEND:
-      case NTOOV:
            calcsize(n->nfile.fname);
            calcsize(n->nfile.next);
            break;
@@ -8779,21 +8609,110 @@ calcsize(const union node *n)
            break;
       };
 }
-#endif /* CALCSIZE_TABLE */
+
 
 static void
-sizenodelist(const struct nodelist *lp)
+sizenodelist(struct nodelist *lp)
 {
        while (lp) {
-               funcblocksize += ALIGN(sizeof(struct nodelist));
+               funcblocksize += SHELL_ALIGN(sizeof(struct nodelist));
                calcsize(lp->n);
                lp = lp->next;
        }
 }
 
 
+static union node *
+copynode(union node *n)
+{
+      union node *new;
+
+      if (n == NULL)
+           return NULL;
+      new = funcblock;
+      funcblock = (char *) funcblock + nodesize[n->type];
+      switch (n->type) {
+      case NCMD:
+           new->ncmd.redirect = copynode(n->ncmd.redirect);
+           new->ncmd.args = copynode(n->ncmd.args);
+           new->ncmd.assign = copynode(n->ncmd.assign);
+           break;
+      case NPIPE:
+           new->npipe.cmdlist = copynodelist(n->npipe.cmdlist);
+           new->npipe.backgnd = n->npipe.backgnd;
+           break;
+      case NREDIR:
+      case NBACKGND:
+      case NSUBSHELL:
+           new->nredir.redirect = copynode(n->nredir.redirect);
+           new->nredir.n = copynode(n->nredir.n);
+           break;
+      case NAND:
+      case NOR:
+      case NSEMI:
+      case NWHILE:
+      case NUNTIL:
+           new->nbinary.ch2 = copynode(n->nbinary.ch2);
+           new->nbinary.ch1 = copynode(n->nbinary.ch1);
+           break;
+      case NIF:
+           new->nif.elsepart = copynode(n->nif.elsepart);
+           new->nif.ifpart = copynode(n->nif.ifpart);
+           new->nif.test = copynode(n->nif.test);
+           break;
+      case NFOR:
+           new->nfor.var = nodesavestr(n->nfor.var);
+           new->nfor.body = copynode(n->nfor.body);
+           new->nfor.args = copynode(n->nfor.args);
+           break;
+      case NCASE:
+           new->ncase.cases = copynode(n->ncase.cases);
+           new->ncase.expr = copynode(n->ncase.expr);
+           break;
+      case NCLIST:
+           new->nclist.body = copynode(n->nclist.body);
+           new->nclist.pattern = copynode(n->nclist.pattern);
+           new->nclist.next = copynode(n->nclist.next);
+           break;
+      case NDEFUN:
+      case NARG:
+           new->narg.backquote = copynodelist(n->narg.backquote);
+           new->narg.text = nodesavestr(n->narg.text);
+           new->narg.next = copynode(n->narg.next);
+           break;
+      case NTO:
+      case NCLOBBER:
+      case NFROM:
+      case NFROMTO:
+      case NAPPEND:
+           new->nfile.fname = copynode(n->nfile.fname);
+           new->nfile.fd = n->nfile.fd;
+           new->nfile.next = copynode(n->nfile.next);
+           break;
+      case NTOFD:
+      case NFROMFD:
+           new->ndup.vname = copynode(n->ndup.vname);
+           new->ndup.dupfd = n->ndup.dupfd;
+           new->ndup.fd = n->ndup.fd;
+           new->ndup.next = copynode(n->ndup.next);
+           break;
+      case NHERE:
+      case NXHERE:
+           new->nhere.doc = copynode(n->nhere.doc);
+           new->nhere.fd = n->nhere.fd;
+           new->nhere.next = copynode(n->nhere.next);
+           break;
+      case NNOT:
+           new->nnot.com = copynode(n->nnot.com);
+           break;
+      };
+      new->type = n->type;
+       return new;
+}
+
+
 static struct nodelist *
-copynodelist(const struct nodelist *lp)
+copynodelist(struct nodelist *lp)
 {
        struct nodelist *start;
        struct nodelist **lpp;
@@ -8801,7 +8720,8 @@ copynodelist(const struct nodelist *lp)
        lpp = &start;
        while (lp) {
                *lpp = funcblock;
-               funcblock = (char *) funcblock + ALIGN(sizeof(struct nodelist));
+               funcblock = (char *) funcblock +
+                   SHELL_ALIGN(sizeof(struct nodelist));
                (*lpp)->n = copynode(lp->n);
                lp = lp->next;
                lpp = &(*lpp)->next;
@@ -8812,96 +8732,128 @@ copynodelist(const struct nodelist *lp)
 
 
 static char *
-nodexstrdup(const char *s)
+nodesavestr(char   *s)
 {
-       const char *p = s;
-       char *q = funcstring;
        char   *rtn = funcstring;
 
-       while ((*q++ = *p++) != '\0')
-               continue;
-       funcstring = q;
+       funcstring = stpcpy(funcstring, s) + 1;
        return rtn;
 }
 
-#ifdef CONFIG_ASH_GETOPTS
-static int getopts (char *, char *, char **, int *, int *);
-#endif
+
+/*
+ * Free a parse tree.
+ */
+
+static void
+freefunc(struct funcnode *f)
+{
+       if (f && --f->count < 0)
+               ckfree(f);
+}
+
+
+static void options(int);
+static void setoption(int, int);
 
 
 /*
  * Process the shell command line arguments.
  */
 
-static void
+void
 procargs(int argc, char **argv)
 {
        int i;
+       const char *xminusc;
+       char **xargv;
 
-       argptr = argv;
+       xargv = argv;
+       arg0 = xargv[0];
        if (argc > 0)
-               argptr++;
+               xargv++;
        for (i = 0; i < NOPTS; i++)
-               optent_val(i) = 2;
+               optlist[i] = 2;
+       argptr = xargv;
        options(1);
-       if (*argptr == NULL && minusc == NULL)
+       xargv = argptr;
+       xminusc = minusc;
+       if (*xargv == NULL) {
+               if (xminusc)
+                       sh_error(bb_msg_requires_arg, "-c");
                sflag = 1;
+       }
        if (iflag == 2 && sflag == 1 && isatty(0) && isatty(1))
                iflag = 1;
        if (mflag == 2)
                mflag = iflag;
        for (i = 0; i < NOPTS; i++)
-               if (optent_val(i) == 2)
-                       optent_val(i) = 0;
-       arg0 = argv[0];
-       if (sflag == 0 && minusc == NULL) {
-               commandname = argv[0];
-               arg0 = *argptr++;
-               setinputfile(arg0, 0);
+               if (optlist[i] == 2)
+                       optlist[i] = 0;
+#if DEBUG == 2
+       debug = 1;
+#endif
+       /* POSIX 1003.2: first arg after -c cmd is $0, remainder $1... */
+       if (xminusc) {
+               minusc = *xargv++;
+               if (*xargv)
+                       goto setarg0;
+       } else if (!sflag) {
+               setinputfile(*xargv, 0);
+setarg0:
+               arg0 = *xargv++;
                commandname = arg0;
        }
-       /* POSIX 1003.2: first arg after -c cmd is $0, remainder $1... */
-       if (argptr && minusc && *argptr)
-               arg0 = *argptr++;
 
-       shellparam.p = argptr;
+       shellparam.p = xargv;
+#ifdef CONFIG_ASH_GETOPTS
        shellparam.optind = 1;
        shellparam.optoff = -1;
+#endif
        /* assert(shellparam.malloc == 0 && shellparam.nparam == 0); */
-       while (*argptr) {
+       while (*xargv) {
                shellparam.nparam++;
-               argptr++;
+               xargv++;
        }
        optschanged();
 }
 
 
-
-/*
- * Process shell options.  The global variable argptr contains a pointer
- * to the argument list; we advance it past the options.
- */
+void
+optschanged(void)
+{
+#ifdef DEBUG
+       opentrace();
+#endif
+       setinteractive(iflag);
+       setjobctl(mflag);
+       setvimode(viflag);
+}
 
 static inline void
-minus_o(const char *name, int val)
+minus_o(char *name, int val)
 {
        int i;
 
        if (name == NULL) {
                out1str("Current option settings\n");
                for (i = 0; i < NOPTS; i++)
-                       printf("%-16s%s\n", optent_name(optlist[i]),
-                               optent_val(i) ? "on" : "off");
+                       out1fmt("%-16s%s\n", optnames(i),
+                               optlist[i] ? "on" : "off");
        } else {
                for (i = 0; i < NOPTS; i++)
-                       if (equal(name, optent_name(optlist[i]))) {
-                               setoption(optent_letter(optlist[i]), val);
+                       if (equal(name, optnames(i))) {
+                               optlist[i] = val;
                                return;
                        }
-               error("Illegal option -o %s", name);
+               sh_error("Illegal option -o %s", name);
        }
 }
 
+/*
+ * Process shell options.  The global variable argptr contains a pointer
+ * to the argument list; we advance it past the options.
+ */
 
 static void
 options(int cmdline)
@@ -8935,21 +8887,15 @@ options(int cmdline)
                }
                while ((c = *p++) != '\0') {
                        if (c == 'c' && cmdline) {
-                               char *q;
-#ifdef NOHACK   /* removing this code allows sh -ce 'foo' for compat */
-                               if (*p == '\0')
-#endif
-                                       q = *argptr++;
-                               if (q == NULL || minusc != NULL)
-                                       error("Bad -c option");
-                               minusc = q;
-#ifdef NOHACK
-                               break;
-#endif
+                               minusc = p;     /* command is after shell args*/
                        } else if (c == 'o') {
                                minus_o(*argptr, val);
                                if (*argptr)
                                        argptr++;
+                       } else if (cmdline && (c == '-')) {     // long options
+                               if (strcmp(p, "login") == 0)
+                                       isloginsh = 1;
+                               break;
                        } else {
                                setoption(c, val);
                        }
@@ -8964,18 +8910,11 @@ setoption(int flag, int val)
        int i;
 
        for (i = 0; i < NOPTS; i++)
-               if (optent_letter(optlist[i]) == flag) {
-                       optent_val(i) = val;
-                       if (val) {
-                               /* #%$ hack for ksh semantics */
-                               if (flag == 'V')
-                                       Eflag = 0;
-                               else if (flag == 'E')
-                                       Vflag = 0;
-                       }
+               if (optletters(i) == flag) {
+                       optlist[i] = val;
                        return;
                }
-       error("Illegal option -%c", flag);
+       sh_error("Illegal option -%c", flag);
        /* NOTREACHED */
 }
 
@@ -8985,7 +8924,7 @@ setoption(int flag, int val)
  * Set the shell parameters.
  */
 
-static void
+void
 setparam(char **argv)
 {
        char **newparam;
@@ -8993,17 +8932,19 @@ setparam(char **argv)
        int nparam;
 
        for (nparam = 0 ; argv[nparam] ; nparam++);
-       ap = newparam = xmalloc((nparam + 1) * sizeof *ap);
+       ap = newparam = ckmalloc((nparam + 1) * sizeof *ap);
        while (*argv) {
-               *ap++ = xstrdup(*argv++);
+               *ap++ = savestr(*argv++);
        }
        *ap = NULL;
        freeparam(&shellparam);
        shellparam.malloc = 1;
        shellparam.nparam = nparam;
        shellparam.p = newparam;
+#ifdef CONFIG_ASH_GETOPTS
        shellparam.optind = 1;
        shellparam.optoff = -1;
+#endif
 }
 
 
@@ -9011,7 +8952,7 @@ setparam(char **argv)
  * Free the list of positional parameters.
  */
 
-static void
+void
 freeparam(volatile struct shparam *param)
 {
        char **ap;
@@ -9029,7 +8970,7 @@ freeparam(volatile struct shparam *param)
  * The shift builtin command.
  */
 
-static int
+int
 shiftcmd(int argc, char **argv)
 {
        int n;
@@ -9039,7 +8980,7 @@ shiftcmd(int argc, char **argv)
        if (argc > 1)
                n = number(argv[1]);
        if (n > shellparam.nparam)
-               error("can't shift that many");
+               sh_error("can't shift that many");
        INTOFF;
        shellparam.nparam -= n;
        for (ap1 = shellparam.p ; --n >= 0 ; ap1++) {
@@ -9048,8 +8989,10 @@ shiftcmd(int argc, char **argv)
        }
        ap2 = shellparam.p;
        while ((*ap2++ = *ap1++) != NULL);
+#ifdef CONFIG_ASH_GETOPTS
        shellparam.optind = 1;
        shellparam.optoff = -1;
+#endif
        INTON;
        return 0;
 }
@@ -9060,11 +9003,11 @@ shiftcmd(int argc, char **argv)
  * The set command builtin.
  */
 
-static int
+int
 setcmd(int argc, char **argv)
 {
        if (argc == 1)
-               return showvarscmd(argc, argv);
+               return showvars(nullstr, 0, VUNSET);
        INTOFF;
        options(0);
        optschanged();
@@ -9076,109 +9019,75 @@ setcmd(int argc, char **argv)
 }
 
 
+#ifdef CONFIG_ASH_GETOPTS
 static void
 getoptsreset(const char *value)
 {
        shellparam.optind = number(value);
        shellparam.optoff = -1;
 }
+#endif
 
 #ifdef CONFIG_LOCALE_SUPPORT
 static void change_lc_all(const char *value)
 {
-       if(value != 0 && *value != 0)
+       if (value != 0 && *value != 0)
                setlocale(LC_ALL, value);
 }
 
 static void change_lc_ctype(const char *value)
 {
-       if(value != 0 && *value != 0)
+       if (value != 0 && *value != 0)
                setlocale(LC_CTYPE, value);
 }
 
 #endif
 
-#ifdef CONFIG_ASH_GETOPTS
-/*
- * The getopts builtin.  Shellparam.optnext points to the next argument
- * to be processed.  Shellparam.optptr points to the next character to
- * be processed in the current argument.  If shellparam.optnext is NULL,
- * then it's the first time getopts has been called.
- */
-
-static int
-getoptscmd(int argc, char **argv)
+#ifdef CONFIG_ASH_RANDOM_SUPPORT
+/* Roughly copied from bash.. */
+static void change_random(const char *value)
 {
-       char **optbase;
+       if(value == NULL) {
+               /* "get", generate */
+               char buf[16];
 
-       if (argc < 3)
-               error("Usage: getopts optstring var [arg]");
-       else if (argc == 3) {
-               optbase = shellparam.p;
-               if (shellparam.optind > shellparam.nparam + 1) {
-                       shellparam.optind = 1;
-                       shellparam.optoff = -1;
-               }
-       }
-       else {
-               optbase = &argv[3];
-               if (shellparam.optind > argc - 2) {
-                       shellparam.optind = 1;
-                       shellparam.optoff = -1;
-               }
+               rseed = rseed * 1103515245 + 12345;
+               sprintf(buf, "%d", (unsigned int)((rseed & 32767)));
+               /* set without recursion */
+               setvar(vrandom.text, buf, VNOFUNC);
+               vrandom.flags &= ~VNOFUNC;
+       } else {
+               /* set/reset */
+               rseed = strtoul(value, (char **)NULL, 10);
        }
-
-       return getopts(argv[1], argv[2], optbase, &shellparam.optind,
-                      &shellparam.optoff);
 }
-
-/*
- * Safe version of setvar, returns 1 on success 0 on failure.
- */
-
-static int
-setvarsafe(const char *name, const char *val, int flags)
-{
-       struct jmploc jmploc;
-       struct jmploc *volatile savehandler = handler;
-       int err = 0;
-#ifdef __GNUC__
-       (void) &err;
 #endif
 
-       if (setjmp(jmploc.loc))
-               err = 1;
-       else {
-               handler = &jmploc;
-               setvar(name, val, flags);
-       }
-       handler = savehandler;
-       return err;
-}
 
+#ifdef CONFIG_ASH_GETOPTS
 static int
-getopts(char *optstr, char *optvar, char **optfirst, int *myoptind, int *optoff)
+getopts(char *optstr, char *optvar, char **optfirst, int *param_optind, int *optoff)
 {
        char *p, *q;
        char c = '?';
        int done = 0;
        int err = 0;
-       char s[10];
-       char **optnext = optfirst + *myoptind - 1;
+       char s[12];
+       char **optnext;
+
+       if(*param_optind < 1)
+               return 1;
+       optnext = optfirst + *param_optind - 1;
 
-       if (*myoptind <= 1 || *optoff < 0 || !(*(optnext - 1)) ||
-           strlen(*(optnext - 1)) < *optoff)
+       if (*param_optind <= 1 || *optoff < 0 || strlen(optnext[-1]) < *optoff)
                p = NULL;
        else
-               p = *(optnext - 1) + *optoff;
+               p = optnext[-1] + *optoff;
        if (p == NULL || *p == '\0') {
                /* Current word is done, advance */
-               if (optnext == NULL)
-                       return 1;
                p = *optnext;
                if (p == NULL || *p != '-' || *++p == '\0') {
 atend:
-                       *myoptind = optnext - optfirst + 1;
                        p = NULL;
                        done = 1;
                        goto out;
@@ -9195,13 +9104,12 @@ atend:
                                s[0] = c;
                                s[1] = '\0';
                                err |= setvarsafe("OPTARG", s, 0);
-                       }
-                       else {
-                               out2fmt("Illegal option -%c\n", c);
+                       } else {
+                               fprintf(stderr, "Illegal option -%c\n", c);
                                (void) unsetvar("OPTARG");
                        }
                        c = '?';
-                       goto bad;
+                       goto out;
                }
                if (*++q == ':')
                        q++;
@@ -9214,43 +9122,71 @@ atend:
                                s[1] = '\0';
                                err |= setvarsafe("OPTARG", s, 0);
                                c = ':';
-                       }
-                       else {
-                               out2fmt("No arg for -%c option\n", c);
+                       } else {
+                               fprintf(stderr, "No arg for -%c option\n", c);
                                (void) unsetvar("OPTARG");
                                c = '?';
                        }
-                       goto bad;
+                       goto out;
                }
 
                if (p == *optnext)
                        optnext++;
-               setvarsafe("OPTARG", p, 0);
+               err |= setvarsafe("OPTARG", p, 0);
                p = NULL;
-       }
-       else
-               setvarsafe("OPTARG", "", 0);
-       *myoptind = optnext - optfirst + 1;
-       goto out;
+       } else
+               err |= setvarsafe("OPTARG", nullstr, 0);
 
-bad:
-       *myoptind = 1;
-       p = NULL;
 out:
        *optoff = p ? p - *(optnext - 1) : -1;
-       snprintf(s, sizeof(s), "%d", *myoptind);
+       *param_optind = optnext - optfirst + 1;
+       fmtstr(s, sizeof(s), "%d", *param_optind);
        err |= setvarsafe("OPTIND", s, VNOFUNC);
        s[0] = c;
        s[1] = '\0';
        err |= setvarsafe(optvar, s, 0);
        if (err) {
-               *myoptind = 1;
+               *param_optind = 1;
                *optoff = -1;
+               flushall();
                exraise(EXERROR);
        }
        return done;
 }
-#endif
+
+/*
+ * The getopts builtin.  Shellparam.optnext points to the next argument
+ * to be processed.  Shellparam.optptr points to the next character to
+ * be processed in the current argument.  If shellparam.optnext is NULL,
+ * then it's the first time getopts has been called.
+ */
+
+int
+getoptscmd(int argc, char **argv)
+{
+       char **optbase;
+
+       if (argc < 3)
+               sh_error("Usage: getopts optstring var [arg]");
+       else if (argc == 3) {
+               optbase = shellparam.p;
+               if (shellparam.optind > shellparam.nparam + 1) {
+                       shellparam.optind = 1;
+                       shellparam.optoff = -1;
+               }
+       }
+       else {
+               optbase = &argv[3];
+               if (shellparam.optind > argc - 2) {
+                       shellparam.optind = 1;
+                       shellparam.optoff = -1;
+               }
+       }
+
+       return getopts(argv[1], argv[2], optbase, &shellparam.optind,
+                      &shellparam.optoff);
+}
+#endif /* CONFIG_ASH_GETOPTS */
 
 /*
  * XXX - should get rid of.  have all builtins use getopt(3).  the
@@ -9281,13 +9217,13 @@ nextopt(const char *optstring)
        c = *p++;
        for (q = optstring ; *q != c ; ) {
                if (*q == '\0')
-                       error("Illegal option -%c", c);
+                       sh_error("Illegal option -%c", c);
                if (*++q == ':')
                        q++;
        }
        if (*++q == ':') {
                if (*p == '\0' && (p = *argptr++) == NULL)
-                       error("No arg for -%c option", c);
+                       sh_error("No arg for -%c option", c);
                optionarg = p;
                p = NULL;
        }
@@ -9295,53 +9231,78 @@ nextopt(const char *optstring)
        return c;
 }
 
-static void
-flushall() {
+
+/*      output.c     */
+
+void
+outstr(const char *p, FILE *file)
+{
+       INTOFF;
+       fputs(p, file);
+       INTON;
+}
+
+void
+flushall(void)
+{
        INTOFF;
        fflush(stdout);
+       fflush(stderr);
        INTON;
 }
 
+void
+flusherr(void)
+{
+       INTOFF;
+       fflush(stderr);
+       INTON;
+}
 
 static void
-out2fmt(const char *fmt, ...)
+outcslow(int c, FILE *dest)
+{
+       INTOFF;
+       putc(c, dest);
+       fflush(dest);
+       INTON;
+}
+
+
+static int
+out1fmt(const char *fmt, ...)
 {
        va_list ap;
+       int r;
+
+       INTOFF;
        va_start(ap, fmt);
-       vfprintf(stderr, fmt, ap);
+       r = vprintf(fmt, ap);
        va_end(ap);
+       INTON;
+       return r;
 }
 
-/*
- * Version of write which resumes after a signal is caught.
- */
 
-static int
-xwrite(int fd, const char *buf, int nbytes)
+int
+fmtstr(char *outbuf, size_t length, const char *fmt, ...)
 {
-       int ntry;
-       int i;
-       int n;
+       va_list ap;
+       int ret;
 
-       n = nbytes;
-       ntry = 0;
-       for (;;) {
-               i = write(fd, buf, n);
-               if (i > 0) {
-                       if ((n -= i) <= 0)
-                               return nbytes;
-                       buf += i;
-                       ntry = 0;
-               } else if (i == 0) {
-                       if (++ntry > 10)
-                               return nbytes - n;
-               } else if (errno != EINTR) {
-                       return -1;
-               }
-       }
+       va_start(ap, fmt);
+       INTOFF;
+       ret = vsnprintf(outbuf, length, fmt, ap);
+       va_end(ap);
+       INTON;
+       return ret;
 }
 
 
+
+/*      parser.c     */
+
+
 /*
  * Shell command parser.
  */
@@ -9349,7 +9310,6 @@ xwrite(int fd, const char *buf, int nbytes)
 #define EOFMARKLEN 79
 
 
-
 struct heredoc {
        struct heredoc *next;   /* next here document in list */
        union node *here;               /* redirection node */
@@ -9357,36 +9317,29 @@ struct heredoc {
        int striptabs;          /* if set, strip leading tabs */
 };
 
-static struct heredoc *heredoclist;     /* list of here documents to read */
-static int parsebackquote;              /* nonzero if we are inside backquotes */
-static int doprompt;                    /* if set, prompt the user */
-static int needprompt;                  /* true if interactive and at start of line */
-static int lasttoken;                   /* last token read */
 
-static char *wordtext;                  /* text of last word returned by readtoken */
 
-static struct nodelist *backquotelist;
-static union node *redirnode;
-static struct heredoc *heredoc;
-static int quoteflag;                   /* set if (part of) last token was quoted */
-static int startlinno;                  /* line # where last token started */
+static struct heredoc *heredoclist;    /* list of here documents to read */
+
+
+static union node *list(int);
+static union node *andor(void);
+static union node *pipeline(void);
+static union node *command(void);
+static union node *simplecmd(void);
+static union node *makename(void);
+static void parsefname(void);
+static void parseheredoc(void);
+static char peektoken(void);
+static int readtoken(void);
+static int xxreadtoken(void);
+static int readtoken1(int firstc, int syntax, char *eofmark, int striptabs);
+static int noexpand(char *);
+static void synexpect(int) ATTRIBUTE_NORETURN;
+static void synerror(const char *) ATTRIBUTE_NORETURN;
+static void setprompt(int);
 
 
-static union node *list (int);
-static union node *andor (void);
-static union node *pipeline (void);
-static union node *command (void);
-static union node *simplecmd(union node **rpp, union node *redir);
-static void parsefname (void);
-static void parseheredoc (void);
-static char peektoken (void);
-static int readtoken (void);
-static int xxreadtoken (void);
-static int readtoken1 (int, int, const char *, int);
-static int noexpand (char *);
-static void synexpect (int) __attribute__((noreturn));
-static void synerror (const char *) __attribute__((noreturn));
-static void setprompt (int);
 
 
 /*
@@ -9394,7 +9347,7 @@ static void setprompt (int);
  * valid parse tree indicating a blank line.)
  */
 
-static union node *
+union node *
 parsecmd(int interact)
 {
        int t;
@@ -9402,9 +9355,7 @@ parsecmd(int interact)
        tokpushback = 0;
        doprompt = interact;
        if (doprompt)
-               setprompt(1);
-       else
-               setprompt(0);
+               setprompt(doprompt);
        needprompt = 0;
        t = readtoken();
        if (t == TEOF)
@@ -9422,24 +9373,24 @@ list(int nlflag)
        union node *n1, *n2, *n3;
        int tok;
 
-       checkkwd = 2;
-       if (nlflag == 0 && peektoken())
+       checkkwd = CHKNL | CHKKWD | CHKALIAS;
+       if (nlflag == 2 && peektoken())
                return NULL;
        n1 = NULL;
        for (;;) {
                n2 = andor();
                tok = readtoken();
                if (tok == TBACKGND) {
-                       if (n2->type == NCMD || n2->type == NPIPE) {
-                               n2->ncmd.backgnd = 1;
-                       } else if (n2->type == NREDIR) {
-                               n2->type = NBACKGND;
+                       if (n2->type == NPIPE) {
+                               n2->npipe.backgnd = 1;
                        } else {
-                               n3 = (union node *)stalloc(sizeof (struct nredir));
-                               n3->type = NBACKGND;
-                               n3->nredir.n = n2;
-                               n3->nredir.redirect = NULL;
-                               n2 = n3;
+                               if (n2->type != NREDIR) {
+                                       n3 = stalloc(sizeof(struct nredir));
+                                       n3->nredir.n = n2;
+                                       n3->nredir.redirect = NULL;
+                                       n2 = n3;
+                               }
+                               n2->type = NBACKGND;
                        }
                }
                if (n1 == NULL) {
@@ -9460,12 +9411,12 @@ list(int nlflag)
                case TNL:
                        if (tok == TNL) {
                                parseheredoc();
-                               if (nlflag)
+                               if (nlflag == 1)
                                        return n1;
                        } else {
                                tokpushback++;
                        }
-                       checkkwd = 2;
+                       checkkwd = CHKNL | CHKKWD | CHKALIAS;
                        if (peektoken())
                                return n1;
                        break;
@@ -9476,7 +9427,7 @@ list(int nlflag)
                                pungetc();              /* push back EOF on input */
                        return n1;
                default:
-                       if (nlflag)
+                       if (nlflag == 1)
                                synexpect(-1);
                        tokpushback++;
                        return n1;
@@ -9487,11 +9438,11 @@ list(int nlflag)
 
 
 static union node *
-andor() {
+andor(void)
+{
        union node *n1, *n2, *n3;
        int t;
 
-       checkkwd = 1;
        n1 = pipeline();
        for (;;) {
                if ((t = readtoken()) == TAND) {
@@ -9502,7 +9453,7 @@ andor() {
                        tokpushback++;
                        return n1;
                }
-               checkkwd = 2;
+               checkkwd = CHKNL | CHKKWD | CHKALIAS;
                n2 = pipeline();
                n3 = (union node *)stalloc(sizeof (struct nbinary));
                n3->type = t;
@@ -9515,7 +9466,8 @@ andor() {
 
 
 static union node *
-pipeline() {
+pipeline(void)
+{
        union node *n1, *n2, *pipenode;
        struct nodelist *lp, *prev;
        int negate;
@@ -9524,7 +9476,7 @@ pipeline() {
        TRACE(("pipeline: entered\n"));
        if (readtoken() == TNOT) {
                negate = !negate;
-               checkkwd = 1;
+               checkkwd = CHKKWD | CHKALIAS;
        } else
                tokpushback++;
        n1 = command();
@@ -9538,7 +9490,7 @@ pipeline() {
                do {
                        prev = lp;
                        lp = (struct nodelist *)stalloc(sizeof (struct nodelist));
-                       checkkwd = 2;
+                       checkkwd = CHKNL | CHKKWD | CHKALIAS;
                        lp->n = command();
                        prev->next = lp;
                } while (readtoken() == TPIPE);
@@ -9558,26 +9510,22 @@ pipeline() {
 
 
 static union node *
-command(void) {
+command(void)
+{
        union node *n1, *n2;
        union node *ap, **app;
        union node *cp, **cpp;
        union node *redir, **rpp;
+       union node **rpp2;
        int t;
 
        redir = NULL;
-       n1 = NULL;
-       rpp = &redir;
-
-       /* Check for redirection which may precede command */
-       while (readtoken() == TREDIR) {
-               *rpp = n2 = redirnode;
-               rpp = &n2->nfile.next;
-               parsefname();
-       }
-       tokpushback++;
+       rpp2 = &redir;
 
        switch (readtoken()) {
+       default:
+               synexpect(-1);
+               /* NOTREACHED */
        case TIF:
                n1 = (union node *)stalloc(sizeof (struct nif));
                n1->type = NIF;
@@ -9601,9 +9549,7 @@ command(void) {
                        n2->nif.elsepart = NULL;
                        tokpushback++;
                }
-               if (readtoken() != TFI)
-                       synexpect(TFI);
-               checkkwd = 1;
+               t = TFI;
                break;
        case TWHILE:
        case TUNTIL: {
@@ -9616,9 +9562,7 @@ TRACE(("expecting DO got %s %s\n", tokname(got), got == TWORD ? wordtext : ""));
                        synexpect(TDO);
                }
                n1->nbinary.ch2 = list(0);
-               if (readtoken() != TDONE)
-                       synexpect(TDONE);
-               checkkwd = 1;
+               t = TDONE;
                break;
        }
        case TFOR:
@@ -9627,7 +9571,7 @@ TRACE(("expecting DO got %s %s\n", tokname(got), got == TWORD ? wordtext : ""));
                n1 = (union node *)stalloc(sizeof (struct nfor));
                n1->type = NFOR;
                n1->nfor.var = wordtext;
-               checkkwd = 1;
+               checkkwd = CHKKWD | CHKALIAS;
                if (readtoken() == TIN) {
                        app = &ap;
                        while (readtoken() == TWORD) {
@@ -9643,11 +9587,9 @@ TRACE(("expecting DO got %s %s\n", tokname(got), got == TWORD ? wordtext : ""));
                        if (lasttoken != TNL && lasttoken != TSEMI)
                                synexpect(-1);
                } else {
-                       static char argvars[5] = {CTLVAR, VSNORMAL|VSQUOTE,
-                                                                  '@', '=', '\0'};
                        n2 = (union node *)stalloc(sizeof (struct narg));
                        n2->type = NARG;
-                       n2->narg.text = argvars;
+                       n2->narg.text = (char *)dolatstr;
                        n2->narg.backquote = NULL;
                        n2->narg.next = NULL;
                        n1->nfor.args = n2;
@@ -9658,13 +9600,11 @@ TRACE(("expecting DO got %s %s\n", tokname(got), got == TWORD ? wordtext : ""));
                        if (lasttoken != TNL && lasttoken != TSEMI)
                                tokpushback++;
                }
-               checkkwd = 2;
+               checkkwd = CHKNL | CHKKWD | CHKALIAS;
                if (readtoken() != TDO)
                        synexpect(TDO);
                n1->nfor.body = list(0);
-               if (readtoken() != TDONE)
-                       synexpect(TDONE);
-               checkkwd = 1;
+               t = TDONE;
                break;
        case TCASE:
                n1 = (union node *)stalloc(sizeof (struct ncase));
@@ -9677,13 +9617,15 @@ TRACE(("expecting DO got %s %s\n", tokname(got), got == TWORD ? wordtext : ""));
                n2->narg.backquote = backquotelist;
                n2->narg.next = NULL;
                do {
-                       checkkwd = 1;
+                       checkkwd = CHKKWD | CHKALIAS;
                } while (readtoken() == TNL);
                if (lasttoken != TIN)
-                       synerror("expecting \"in\"");
+                       synexpect(TIN);
                cpp = &n1->ncase.cases;
-               checkkwd = 2, readtoken();
-               do {
+next_case:
+               checkkwd = CHKNL | CHKKWD;
+               t = readtoken();
+               while(t != TESAC) {
                        if (lasttoken == TLP)
                                readtoken();
                        *cpp = cp = (union node *)stalloc(sizeof (struct nclist));
@@ -9694,7 +9636,7 @@ TRACE(("expecting DO got %s %s\n", tokname(got), got == TWORD ? wordtext : ""));
                                ap->type = NARG;
                                ap->narg.text = wordtext;
                                ap->narg.backquote = backquotelist;
-                               if (checkkwd = 2, readtoken() != TPIPE)
+                               if (readtoken() != TPIPE)
                                        break;
                                app = &ap->narg.next;
                                readtoken();
@@ -9702,59 +9644,44 @@ TRACE(("expecting DO got %s %s\n", tokname(got), got == TWORD ? wordtext : ""));
                        ap->narg.next = NULL;
                        if (lasttoken != TRP)
                                synexpect(TRP);
-                       cp->nclist.body = list(0);
+                       cp->nclist.body = list(2);
 
-                       checkkwd = 2;
+                       cpp = &cp->nclist.next;
+
+                       checkkwd = CHKNL | CHKKWD;
                        if ((t = readtoken()) != TESAC) {
                                if (t != TENDCASE)
                                        synexpect(TENDCASE);
                                else
-                                       checkkwd = 2, readtoken();
+                                       goto next_case;
                        }
-                       cpp = &cp->nclist.next;
-               } while(lasttoken != TESAC);
+               }
                *cpp = NULL;
-               checkkwd = 1;
-               break;
+               goto redir;
        case TLP:
                n1 = (union node *)stalloc(sizeof (struct nredir));
                n1->type = NSUBSHELL;
                n1->nredir.n = list(0);
                n1->nredir.redirect = NULL;
-               if (readtoken() != TRP)
-                       synexpect(TRP);
-               checkkwd = 1;
+               t = TRP;
                break;
        case TBEGIN:
                n1 = list(0);
-               if (readtoken() != TEND)
-                       synexpect(TEND);
-               checkkwd = 1;
+               t = TEND;
                break;
-       /* Handle an empty command like other simple commands.  */
-       case TSEMI:
-       case TAND:
-       case TOR:
-       case TNL:
-       case TEOF:
-       case TRP:
-       case TBACKGND:
-               /*
-                * An empty command before a ; doesn't make much sense, and
-                * should certainly be disallowed in the case of `if ;'.
-                */
-               if (!redir)
-                       synexpect(-1);
        case TWORD:
+       case TREDIR:
                tokpushback++;
-               n1 = simplecmd(rpp, redir);
-               return n1;
-       default:
-               synexpect(-1);
-               /* NOTREACHED */
+               return simplecmd();
        }
 
+       if (readtoken() != t)
+               synexpect(t);
+
+redir:
        /* Now check for redirection which may follow command */
+       checkkwd = CHKKWD | CHKALIAS;
+       rpp = rpp2;
        while (readtoken() == TREDIR) {
                *rpp = n2 = redirnode;
                rpp = &n2->nfile.next;
@@ -9777,41 +9704,36 @@ TRACE(("expecting DO got %s %s\n", tokname(got), got == TWORD ? wordtext : ""));
 
 
 static union node *
-simplecmd(union node **rpp, union node *redir) {
+simplecmd(void) {
        union node *args, **app;
        union node *n = NULL;
        union node *vars, **vpp;
-       union node **orig_rpp;
+       union node **rpp, *redir;
+       int savecheckkwd;
 
        args = NULL;
        app = &args;
        vars = NULL;
        vpp = &vars;
-
-       /* If we don't have any redirections already, then we must reset
-         rpp to be the address of the local redir variable.  */
-       if (redir == 0)
+       redir = NULL;
        rpp = &redir;
-       /* We save the incoming value, because we need this for shell
-         functions.  There can not be a redirect or an argument between
-         the function name and the open parenthesis.  */
-       orig_rpp = rpp;
 
-       checkalias = 2;
+       savecheckkwd = CHKALIAS;
        for (;;) {
+               checkkwd = savecheckkwd;
                switch (readtoken()) {
                case TWORD:
-               case TASSIGN:
                        n = (union node *)stalloc(sizeof (struct narg));
                        n->type = NARG;
                        n->narg.text = wordtext;
                        n->narg.backquote = backquotelist;
-                       if (lasttoken == TWORD) {
-                               *app = n;
-                               app = &n->narg.next;
-                       } else {
+                       if (savecheckkwd && isassignment(wordtext)) {
                                *vpp = n;
                                vpp = &n->narg.next;
+                       } else {
+                               *app = n;
+                               app = &n->narg.next;
+                               savecheckkwd = 0;
                        }
                        break;
                case TREDIR:
@@ -9822,13 +9744,24 @@ simplecmd(union node **rpp, union node *redir) {
                case TLP:
                        if (
                                args && app == &args->narg.next &&
-                               !vars && rpp == orig_rpp
+                               !vars && !redir
                        ) {
+                               struct builtincmd *bcmd;
+                               const char *name;
+
                                /* We have a function */
                                if (readtoken() != TRP)
                                        synexpect(TRP);
+                               name = n->narg.text;
+                               if (
+                                       !goodname(name) || (
+                                               (bcmd = find_builtin(name)) &&
+                                               IS_BUILTIN_SPECIAL(bcmd)
+                                       )
+                               )
+                                       synerror("Bad function name");
                                n->type = NDEFUN;
-                               checkkwd = 2;
+                               checkkwd = CHKNL | CHKKWD | CHKALIAS;
                                n->narg.next = command();
                                return n;
                        }
@@ -9844,7 +9777,6 @@ out:
        *rpp = NULL;
        n = (union node *)stalloc(sizeof (struct ncmd));
        n->type = NCMD;
-       n->ncmd.backgnd = 0;
        n->ncmd.args = args;
        n->ncmd.assign = vars;
        n->ncmd.redirect = redir;
@@ -9852,7 +9784,8 @@ out:
 }
 
 static union node *
-makename(void) {
+makename(void)
+{
        union node *n;
 
        n = (union node *)stalloc(sizeof (struct narg));
@@ -9863,7 +9796,7 @@ makename(void) {
        return n;
 }
 
-static void fixredir(union node *n, const char *text, int err)
+void fixredir(union node *n, const char *text, int err)
 {
        TRACE(("Fix redir %s %d\n", text, err));
        if (!err)
@@ -9884,7 +9817,8 @@ static void fixredir(union node *n, const char *text, int err)
 
 
 static void
-parsefname(void) {
+parsefname(void)
+{
        union node *n = redirnode;
 
        if (readtoken() != TWORD)
@@ -9897,10 +9831,6 @@ parsefname(void) {
                if (quoteflag == 0)
                        n->type = NXHERE;
                TRACE(("Here document %d\n", n->type));
-               if (here->striptabs) {
-                       while (*wordtext == '\t')
-                               wordtext++;
-               }
                if (! noexpand(wordtext) || (i = strlen(wordtext)) == 0 || i > EOFMARKLEN)
                        synerror("Illegal eof marker for << redirection");
                rmescapes(wordtext);
@@ -9925,16 +9855,17 @@ parsefname(void) {
  */
 
 static void
-parseheredoc() {
+parseheredoc(void)
+{
        struct heredoc *here;
        union node *n;
 
-       while (heredoclist) {
-               here = heredoclist;
-               heredoclist = here->next;
+       here = heredoclist;
+       heredoclist = 0;
+
+       while (here) {
                if (needprompt) {
                        setprompt(2);
-                       needprompt = 0;
                }
                readtoken1(pgetc(), here->here->type == NHERE? SQSYNTAX : DQSYNTAX,
                                here->eofmark, here->striptabs);
@@ -9944,11 +9875,12 @@ parseheredoc() {
                n->narg.text = wordtext;
                n->narg.backquote = backquotelist;
                here->here->nhere.doc = n;
+               here = here->next;
        }
 }
 
-static char
-peektoken() {
+static char peektoken(void)
+{
        int t;
 
        t = readtoken();
@@ -9957,15 +9889,9 @@ peektoken() {
 }
 
 static int
-readtoken() {
+readtoken(void)
+{
        int t;
-
-#ifdef CONFIG_ASH_ALIAS
-       int savecheckalias = checkalias;
-       int savecheckkwd = checkkwd;
-       struct alias *ap;
-#endif
-
 #ifdef DEBUG
        int alreadyseen = tokpushback;
 #endif
@@ -9976,62 +9902,51 @@ top:
 
        t = xxreadtoken();
 
-#ifdef CONFIG_ASH_ALIAS
-       checkalias = savecheckalias;
-#endif
-
-       if (checkkwd) {
-               /*
-                * eat newlines
-                */
-               if (checkkwd == 2) {
-                       checkkwd = 0;
-                       while (t == TNL) {
-                               parseheredoc();
-                               t = xxreadtoken();
-                       }
-               }
-               checkkwd = 0;
-               /*
-                * check for keywords
-                */
-               if (t == TWORD && !quoteflag)
-               {
-                       const char *const *pp;
-
-                       if ((pp = findkwd(wordtext))) {
-                               lasttoken = t = pp - tokname_array;
-                               TRACE(("keyword %s recognized\n", tokname(t)));
-                               goto out;
-                       }
+       /*
+        * eat newlines
+        */
+       if (checkkwd & CHKNL) {
+               while (t == TNL) {
+                       parseheredoc();
+                       t = xxreadtoken();
                }
        }
 
+       if (t != TWORD || quoteflag) {
+               goto out;
+       }
+
+       /*
+        * check for keywords
+        */
+       if (checkkwd & CHKKWD) {
+               const char *const *pp;
 
-       if (t != TWORD) {
-               if (t != TREDIR) {
-                       checkalias = 0;
+               if ((pp = findkwd(wordtext))) {
+                       lasttoken = t = pp - tokname_array;
+                       TRACE(("keyword %s recognized\n", tokname(t)));
+                       goto out;
                }
-       } else if (checkalias == 2 && isassignment(wordtext)) {
-               lasttoken = t = TASSIGN;
+       }
+
+       if (checkkwd & CHKALIAS) {
 #ifdef CONFIG_ASH_ALIAS
-       } else if (checkalias) {
-               if (!quoteflag && (ap = *__lookupalias(wordtext)) != NULL && !(ap->flag & ALIASINUSE)) {
+               struct alias *ap;
+               if ((ap = lookupalias(wordtext, 1)) != NULL) {
                        if (*ap->val) {
-                               pushstring(ap->val, strlen(ap->val), ap);
+                               pushstring(ap->val, ap);
                        }
-                       checkkwd = savecheckkwd;
                        goto top;
                }
-               checkalias = 0;
 #endif
        }
 out:
+       checkkwd = 0;
 #ifdef DEBUG
        if (!alreadyseen)
-           TRACE(("token %s %s\n", tokname(t), t == TWORD || t == TASSIGN ? wordtext : ""));
+           TRACE(("token %s %s\n", tokname(t), t == TWORD ? wordtext : ""));
        else
-           TRACE(("reread token %s %s\n", tokname(t), t == TWORD || t == TASSIGN ? wordtext : ""));
+           TRACE(("reread token %s %s\n", tokname(t), t == TWORD ? wordtext : ""));
 #endif
        return (t);
 }
@@ -10058,12 +9973,14 @@ out:
 #define NEW_xxreadtoken
 #ifdef NEW_xxreadtoken
 
-static const char xxreadtoken_chars[] = "\n()&|;"; /* singles must be first! */
+/* singles must be first! */
+static const char xxreadtoken_chars[7] = { '\n', '(', ')', '&', '|', ';', 0 };
+
 static const char xxreadtoken_tokens[] = {
-       TNL, TLP, TRP,                          /* only single occurrence allowed */
-       TBACKGND, TPIPE, TSEMI,         /* if single occurrence */
-       TEOF,                                           /* corresponds to trailing nul */
-       TAND, TOR, TENDCASE,            /* if double occurrence */
+       TNL, TLP, TRP,          /* only single occurrence allowed */
+       TBACKGND, TPIPE, TSEMI, /* if single occurrence */
+       TEOF,                   /* corresponds to trailing nul */
+       TAND, TOR, TENDCASE,    /* if double occurrence */
 };
 
 #define xxreadtoken_doubles \
@@ -10071,8 +9988,8 @@ static const char xxreadtoken_tokens[] = {
 #define xxreadtoken_singles \
        (sizeof(xxreadtoken_chars) - xxreadtoken_doubles - 1)
 
-static int
-xxreadtoken() {
+static int xxreadtoken(void)
+{
        int c;
 
        if (tokpushback) {
@@ -10081,45 +9998,45 @@ xxreadtoken() {
        }
        if (needprompt) {
                setprompt(2);
-               needprompt = 0;
        }
        startlinno = plinno;
-       for (;;) {      /* until token or start of word found */
+       for (;;) {                      /* until token or start of word found */
                c = pgetc_macro();
 
-               if ((c!=' ') && (c!='\t')
+               if ((c != ' ') && (c != '\t')
 #ifdef CONFIG_ASH_ALIAS
-                       && (c!=PEOA)
+                       && (c != PEOA)
 #endif
                        ) {
-                       if (c=='#') {
+                       if (c == '#') {
                                while ((c = pgetc()) != '\n' && c != PEOF);
                                pungetc();
-                       } else if (c=='\\') {
+                       } else if (c == '\\') {
                                if (pgetc() != '\n') {
                                        pungetc();
                                        goto READTOKEN1;
                                }
                                startlinno = ++plinno;
-                               setprompt(doprompt ? 2 : 0);
+                               if (doprompt)
+                                       setprompt(2);
                        } else {
                                const char *p
                                        = xxreadtoken_chars + sizeof(xxreadtoken_chars) - 1;
 
-                               if (c!=PEOF) {
-                                       if (c=='\n') {
+                               if (c != PEOF) {
+                                       if (c == '\n') {
                                                plinno++;
                                                needprompt = doprompt;
                                        }
 
                                        p = strchr(xxreadtoken_chars, c);
                                        if (p == NULL) {
-                                       READTOKEN1:
-                                               return readtoken1(c, BASESYNTAX, (char *)NULL, 0);
+                                         READTOKEN1:
+                                               return readtoken1(c, BASESYNTAX, (char *) NULL, 0);
                                        }
-                       
-                                       if (p-xxreadtoken_chars >= xxreadtoken_singles) {
-                                               if (pgetc() == *p) { /* double occurrence? */
+
+                                       if (p - xxreadtoken_chars >= xxreadtoken_singles) {
+                                               if (pgetc() == *p) {    /* double occurrence? */
                                                        p += xxreadtoken_doubles + 1;
                                                } else {
                                                        pungetc();
@@ -10127,7 +10044,7 @@ xxreadtoken() {
                                        }
                                }
 
-                               return lasttoken = xxreadtoken_tokens[p-xxreadtoken_chars];
+                               return lasttoken = xxreadtoken_tokens[p - xxreadtoken_chars];
                        }
                }
        }
@@ -10138,7 +10055,8 @@ xxreadtoken() {
 #define RETURN(token)   return lasttoken = token
 
 static int
-xxreadtoken() {
+xxreadtoken(void)
+{
        int c;
 
        if (tokpushback) {
@@ -10147,7 +10065,6 @@ xxreadtoken() {
        }
        if (needprompt) {
                setprompt(2);
-               needprompt = 0;
        }
        startlinno = plinno;
        for (;;) {      /* until token or start of word found */
@@ -10167,8 +10084,6 @@ xxreadtoken() {
                                startlinno = ++plinno;
                                if (doprompt)
                                        setprompt(2);
-                               else
-                                       setprompt(0);
                                continue;
                        }
                        pungetc();
@@ -10206,7 +10121,8 @@ breakloop:
        return readtoken1(c, BASESYNTAX, (char *)NULL, 0);
 #undef RETURN
 }
-#endif
+#endif /* NEW_xxreadtoken */
+
 
 /*
  * If eofmark is NULL, read a word or a redirection symbol.  If eofmark
@@ -10228,21 +10144,21 @@ breakloop:
 #define PARSEARITH()    {goto parsearith; parsearith_return:;}
 
 static int
-readtoken1(int firstc, int syntax, const char *eofmark, int striptabs)
+readtoken1(int firstc, int syntax, char *eofmark, int striptabs)
 {
        int c = firstc;
        char *out;
        int len;
        char line[EOFMARKLEN + 1];
-       struct nodelist *bqlist;
-       int quotef;
-       int dblquote;
-       int varnest;    /* levels of variables expansion */
-       int arinest;    /* levels of arithmetic expansion */
-       int parenlevel; /* levels of parens in arithmetic */
-       int dqvarnest;  /* levels of variables expansion within double quotes */
-       int oldstyle;
-       int prevsyntax; /* syntax before arithmetic */
+       struct nodelist *bqlist = 0;
+       int quotef = 0;
+       int dblquote = 0;
+       int varnest = 0;    /* levels of variables expansion */
+       int arinest = 0;    /* levels of arithmetic expansion */
+       int parenlevel = 0; /* levels of parens in arithmetic */
+       int dqvarnest = 0;  /* levels of variables expansion within double quotes */
+       int oldstyle = 0;
+       int prevsyntax = 0; /* syntax before arithmetic */
 #if __GNUC__
        /* Avoid longjmp clobbering */
        (void) &out;
@@ -10272,8 +10188,8 @@ readtoken1(int firstc, int syntax, const char *eofmark, int striptabs)
        loop: { /* for each line, until end of word */
                CHECKEND();     /* set c to PEOF if at end of here document */
                for (;;) {      /* until end of line or end of word */
-                       CHECKSTRSPACE(3, out);  /* permit 3 calls to USTPUTC */
-                       switch(SIT(c,syntax)) {
+                       CHECKSTRSPACE(4, out);  /* permit 4 calls to USTPUTC */
+                       switch(SIT(c, syntax)) {
                        case CNL:       /* '\n' */
                                if (syntax == BASESYNTAX)
                                        goto endword;   /* exit outer loop */
@@ -10281,66 +10197,63 @@ readtoken1(int firstc, int syntax, const char *eofmark, int striptabs)
                                plinno++;
                                if (doprompt)
                                        setprompt(2);
-                               else
-                                       setprompt(0);
                                c = pgetc();
                                goto loop;              /* continue outer loop */
                        case CWORD:
                                USTPUTC(c, out);
                                break;
                        case CCTL:
-                               if ((eofmark == NULL || dblquote) &&
-                                   dqvarnest == 0)
+                               if (eofmark == NULL || dblquote)
                                        USTPUTC(CTLESC, out);
                                USTPUTC(c, out);
                                break;
                        case CBACK:     /* backslash */
                                c = pgetc2();
                                if (c == PEOF) {
+                                       USTPUTC(CTLESC, out);
                                        USTPUTC('\\', out);
                                        pungetc();
                                } else if (c == '\n') {
                                        if (doprompt)
                                                setprompt(2);
-                                       else
-                                               setprompt(0);
                                } else {
-                                       if (dblquote && c != '\\' && c != '`' && c != '$'
-                                                        && (c != '"' || eofmark != NULL))
+                                       if (dblquote &&
+                                               c != '\\' && c != '`' &&
+                                               c != '$' && (
+                                                       c != '"' ||
+                                                       eofmark != NULL)
+                                       ) {
+                                               USTPUTC(CTLESC, out);
                                                USTPUTC('\\', out);
-                                       if (SIT(c,SQSYNTAX) == CCTL)
+                                       }
+                                       if (SIT(c, SQSYNTAX) == CCTL)
                                                USTPUTC(CTLESC, out);
-                                       else if (eofmark == NULL)
-                                               USTPUTC(CTLQUOTEMARK, out);
                                        USTPUTC(c, out);
                                        quotef++;
                                }
                                break;
                        case CSQUOTE:
-                               if (eofmark == NULL)
-                                       USTPUTC(CTLQUOTEMARK, out);
                                syntax = SQSYNTAX;
+quotemark:
+                               if (eofmark == NULL) {
+                                       USTPUTC(CTLQUOTEMARK, out);
+                               }
                                break;
                        case CDQUOTE:
-                               if (eofmark == NULL)
-                                       USTPUTC(CTLQUOTEMARK, out);
                                syntax = DQSYNTAX;
                                dblquote = 1;
-                               break;
+                               goto quotemark;
                        case CENDQUOTE:
                                if (eofmark != NULL && arinest == 0 &&
                                    varnest == 0) {
                                        USTPUTC(c, out);
                                } else {
-                                       if (arinest) {
-                                               syntax = ARISYNTAX;
-                                               dblquote = 0;
-                                       } else if (eofmark == NULL &&
-                                                  dqvarnest == 0) {
+                                       if (dqvarnest == 0) {
                                                syntax = BASESYNTAX;
                                                dblquote = 0;
                                        }
                                        quotef++;
+                                       goto quotemark;
                                }
                                break;
                        case CVAR:      /* '$' */
@@ -10408,16 +10321,19 @@ readtoken1(int firstc, int syntax, const char *eofmark, int striptabs)
                }
        }
 endword:
+#ifdef CONFIG_ASH_MATH_SUPPORT
        if (syntax == ARISYNTAX)
                synerror("Missing '))'");
+#endif
        if (syntax != BASESYNTAX && ! parsebackquote && eofmark == NULL)
                synerror("Unterminated quoted string");
        if (varnest != 0) {
                startlinno = plinno;
+               /* { */
                synerror("Missing '}'");
        }
        USTPUTC('\0', out);
-       len = out - stackblock();
+       len = out - (char *)stackblock();
        out = stackblock();
        if (eofmark == NULL) {
                if ((c == '>' || c == '<')
@@ -10459,7 +10375,7 @@ checkend: {
                }
                if (c == *eofmark) {
                        if (pfgets(line, sizeof line) != NULL) {
-                               const char *p, *q;
+                               char *p, *q;
 
                                p = line;
                                for (q = eofmark + 1 ; *q && *p == *q ; p++, q++);
@@ -10468,7 +10384,7 @@ checkend: {
                                        plinno++;
                                        needprompt = doprompt;
                                } else {
-                                       pushstring(line, strlen(line), NULL);
+                                       pushstring(line, NULL);
                                }
                        }
                }
@@ -10493,10 +10409,10 @@ parseredir: {
                c = pgetc();
                if (c == '>')
                        np->type = NAPPEND;
+               else if (c == '|')
+                       np->type = NCLOBBER;
                else if (c == '&')
                        np->type = NTOFD;
-               else if (c == '|')
-                       np->type = NTOOV;
                else {
                        np->type = NTO;
                        pungetc();
@@ -10555,21 +10471,25 @@ parsesub: {
 
        c = pgetc();
        if (
-               c <= PEOA  ||
+               c <= PEOA_OR_PEOF  ||
                (c != '(' && c != '{' && !is_name(c) && !is_special(c))
        ) {
                USTPUTC('$', out);
                pungetc();
        } else if (c == '(') {  /* $(command) or $((arith)) */
                if (pgetc() == '(') {
+#ifdef CONFIG_ASH_MATH_SUPPORT
                        PARSEARITH();
+#else
+                       synerror("We unsupport $((arith))");
+#endif
                } else {
                        pungetc();
                        PARSEBACKQNEW();
                }
        } else {
                USTPUTC(CTLVAR, out);
-               typeloc = out - stackblock();
+               typeloc = out - (char *)stackblock();
                USTPUTC(VSNORMAL, out);
                subtype = VSNORMAL;
                if (c == '{') {
@@ -10583,14 +10503,14 @@ parsesub: {
                        else
                                subtype = 0;
                }
-               if (c > PEOA && is_name(c)) {
+               if (c > PEOA_OR_PEOF && is_name(c)) {
                        do {
                                STPUTC(c, out);
                                c = pgetc();
-                       } while (c > PEOA && is_in_name(c));
+                       } while (c > PEOA_OR_PEOF && is_in_name(c));
                } else if (is_digit(c)) {
                        do {
-                               USTPUTC(c, out);
+                               STPUTC(c, out);
                                c = pgetc();
                        } while (is_digit(c));
                }
@@ -10634,10 +10554,10 @@ badsub:                 synerror("Bad substitution");
                }
                if (dblquote || arinest)
                        flags |= VSQUOTE;
-               *(stackblock() + typeloc) = subtype | flags;
+               *((char *)stackblock() + typeloc) = subtype | flags;
                if (subtype != VSNORMAL) {
                        varnest++;
-                       if (dblquote) {
+                       if (dblquote || arinest) {
                                dqvarnest++;
                        }
                }
@@ -10660,8 +10580,8 @@ parsebackq: {
        char *volatile str;
        struct jmploc jmploc;
        struct jmploc *volatile savehandler;
-       int savelen;
-       int saveprompt;
+       size_t savelen;
+       int saveprompt = 0;
 #ifdef __GNUC__
        (void) &saveprompt;
 #endif
@@ -10676,9 +10596,9 @@ parsebackq: {
        }
        INTOFF;
        str = NULL;
-       savelen = out - stackblock();
+       savelen = out - (char *)stackblock();
        if (savelen > 0) {
-               str = xmalloc(savelen);
+               str = ckmalloc(savelen);
                memcpy(str, stackblock(), savelen);
        }
        savehandler = handler;
@@ -10690,7 +10610,7 @@ parsebackq: {
                   reread it as input, interpreting it normally.  */
                char *pout;
                int pc;
-               int psavelen;
+               size_t psavelen;
                char *pstr;
 
 
@@ -10698,7 +10618,6 @@ parsebackq: {
                for (;;) {
                        if (needprompt) {
                                setprompt(2);
-                               needprompt = 0;
                        }
                        switch (pc = pgetc()) {
                        case '`':
@@ -10709,8 +10628,6 @@ parsebackq: {
                                        plinno++;
                                        if (doprompt)
                                                setprompt(2);
-                                       else
-                                               setprompt(0);
                                        /*
                                         * If eating a newline, avoid putting
                                         * the newline into the new character
@@ -10722,7 +10639,7 @@ parsebackq: {
                                if (pc != '\\' && pc != '`' && pc != '$'
                                    && (!dblquote || pc != '"'))
                                        STPUTC('\\', pout);
-                               if (pc > PEOA) {
+                               if (pc > PEOA_OR_PEOF) {
                                        break;
                                }
                                /* fall through */
@@ -10746,7 +10663,7 @@ parsebackq: {
                }
 done:
                STPUTC('\0', pout);
-               psavelen = pout - stackblock();
+               psavelen = pout - (char *)stackblock();
                if (psavelen > 0) {
                        pstr = grabstackstr(pout);
                        setinputstring(pstr);
@@ -10764,7 +10681,7 @@ done:
                doprompt = 0;
        }
 
-       n = list(0);
+       n = list(2);
 
        if (oldstyle)
                doprompt = saveprompt;
                str = NULL;
                INTON;
        }
-       parsebackquote = savepbq;
-       handler = savehandler;
-       if (arinest || dblquote)
-               USTPUTC(CTLBACKQ | CTLQUOTE, out);
-       else
-               USTPUTC(CTLBACKQ, out);
-       if (oldstyle)
-               goto parsebackq_oldreturn;
-       else
-               goto parsebackq_newreturn;
+       parsebackquote = savepbq;
+       handler = savehandler;
+       if (arinest || dblquote)
+               USTPUTC(CTLBACKQ | CTLQUOTE, out);
+       else
+               USTPUTC(CTLBACKQ, out);
+       if (oldstyle)
+               goto parsebackq_oldreturn;
+       else
+               goto parsebackq_newreturn;
+}
+
+#ifdef CONFIG_ASH_MATH_SUPPORT
+/*
+ * Parse an arithmetic expansion (indicate start of one and set state)
+ */
+parsearith: {
+
+       if (++arinest == 1) {
+               prevsyntax = syntax;
+               syntax = ARISYNTAX;
+               USTPUTC(CTLARI, out);
+               if (dblquote)
+                       USTPUTC('"',out);
+               else
+                       USTPUTC(' ',out);
+       } else {
+               /*
+                * we collapse embedded arithmetic expansion to
+                * parenthesis, which should be equivalent
+                */
+               USTPUTC('(', out);
+       }
+       goto parsearith_return;
+}
+#endif
+
+} /* end of readtoken */
+
+
+
+/*
+ * Returns true if the text contains nothing to expand (no dollar signs
+ * or backquotes).
+ */
+
+static int
+noexpand(char *text)
+{
+       char *p;
+       char c;
+
+       p = text;
+       while ((c = *p++) != '\0') {
+               if (c == CTLQUOTEMARK)
+                       continue;
+               if (c == CTLESC)
+                       p++;
+               else if (SIT(c, BASESYNTAX) == CCTL)
+                       return 0;
+       }
+       return 1;
+}
+
+
+/*
+ * Return of a legal variable name (a letter or underscore followed by zero or
+ * more letters, underscores, and digits).
+ */
+
+static char *
+endofname(const char *name)
+{
+       char *p;
+
+       p = (char *) name;
+       if (! is_name(*p))
+               return p;
+       while (*++p) {
+               if (! is_in_name(*p))
+                       break;
+       }
+       return p;
+}
+
+
+/*
+ * Called when an unexpected token is read during the parse.  The argument
+ * is the token that is expected, or -1 if more than one type of token can
+ * occur at this point.
+ */
+
+static void synexpect(int token)
+{
+       char msg[64];
+       int l;
+
+       l = sprintf(msg, "%s unexpected", tokname(lasttoken));
+       if (token >= 0)
+               sprintf(msg + l, " (expecting %s)", tokname(token));
+       synerror(msg);
+       /* NOTREACHED */
+}
+
+static void
+synerror(const char *msg)
+{
+       sh_error("Syntax error: %s", msg);
+       /* NOTREACHED */
+}
+
+
+/*
+ * called by editline -- any expansions to the prompt
+ *    should be added here.
+ */
+
+#ifdef CONFIG_ASH_EXPAND_PRMT
+static const char *
+expandstr(const char *ps)
+{
+       union node n;
+
+       /* XXX Fix (char *) cast. */
+       setinputstring((char *)ps);
+       readtoken1(pgetc(), DQSYNTAX, nullstr, 0);
+       popfile();
+
+       n.narg.type = NARG;
+       n.narg.next = NULL;
+       n.narg.text = wordtext;
+       n.narg.backquote = backquotelist;
+
+       expandarg(&n, NULL, 0);
+       return stackblock();
+}
+#endif
+
+static void setprompt(int whichprompt)
+{
+       const char *prompt;
+#ifdef CONFIG_ASH_EXPAND_PRMT
+       struct stackmark smark;
+#endif
+
+       needprompt = 0;
+
+       switch (whichprompt) {
+       case 1:
+               prompt = ps1val();
+               break;
+       case 2:
+               prompt = ps2val();
+               break;
+       default:                        /* 0 */
+               prompt = nullstr;
+       }
+#ifdef CONFIG_ASH_EXPAND_PRMT
+       setstackmark(&smark);
+       stalloc(stackblocksize());
+#endif
+       putprompt(expandstr(prompt));
+#ifdef CONFIG_ASH_EXPAND_PRMT
+       popstackmark(&smark);
+#endif
+}
+
+
+static const char *const *findkwd(const char *s)
+{
+       return bsearch(s, tokname_array + KWDOFFSET,
+                      (sizeof(tokname_array) / sizeof(const char *)) - KWDOFFSET,
+                                  sizeof(const char *), pstrcmp);
+}
+
+/*      redir.c      */
+
+/*
+ * Code for dealing with input/output redirection.
+ */
+
+#define EMPTY -2                /* marks an unused slot in redirtab */
+#ifndef PIPE_BUF
+# define PIPESIZE 4096          /* amount of buffering in a pipe */
+#else
+# define PIPESIZE PIPE_BUF
+#endif
+
+/*
+ * Open a file in noclobber mode.
+ * The code was copied from bash.
+ */
+static inline int
+noclobberopen(const char *fname)
+{
+       int r, fd;
+       struct stat finfo, finfo2;
+
+       /*
+        * If the file exists and is a regular file, return an error
+        * immediately.
+        */
+       r = stat(fname, &finfo);
+       if (r == 0 && S_ISREG(finfo.st_mode)) {
+               errno = EEXIST;
+               return -1;
+       }
+
+       /*
+        * If the file was not present (r != 0), make sure we open it
+        * exclusively so that if it is created before we open it, our open
+        * will fail.  Make sure that we do not truncate an existing file.
+        * Note that we don't turn on O_EXCL unless the stat failed -- if the
+        * file was not a regular file, we leave O_EXCL off.
+        */
+       if (r != 0)
+               return open(fname, O_WRONLY|O_CREAT|O_EXCL, 0666);
+       fd = open(fname, O_WRONLY|O_CREAT, 0666);
+
+       /* If the open failed, return the file descriptor right away. */
+       if (fd < 0)
+               return fd;
+
+       /*
+        * OK, the open succeeded, but the file may have been changed from a
+        * non-regular file to a regular file between the stat and the open.
+        * We are assuming that the O_EXCL open handles the case where FILENAME
+        * did not exist and is symlinked to an existing file between the stat
+        * and open.
+        */
+
+       /*
+        * If we can open it and fstat the file descriptor, and neither check
+        * revealed that it was a regular file, and the file has not been
+        * replaced, return the file descriptor.
+        */
+        if (fstat(fd, &finfo2) == 0 && !S_ISREG(finfo2.st_mode) &&
+            finfo.st_dev == finfo2.st_dev && finfo.st_ino == finfo2.st_ino)
+               return fd;
+
+       /* The file has been replaced.  badness. */
+       close(fd);
+       errno = EEXIST;
+       return -1;
+}
+
+/*
+ * Handle here documents.  Normally we fork off a process to write the
+ * data to a pipe.  If the document is short, we can stuff the data in
+ * the pipe without forking.
+ */
+
+static inline int
+openhere(union node *redir)
+{
+       int pip[2];
+       size_t len = 0;
+
+       if (pipe(pip) < 0)
+               sh_error("Pipe call failed");
+       if (redir->type == NHERE) {
+               len = strlen(redir->nhere.doc->narg.text);
+               if (len <= PIPESIZE) {
+                       full_write(pip[1], redir->nhere.doc->narg.text, len);
+                       goto out;
+               }
+       }
+       if (forkshell((struct job *)NULL, (union node *)NULL, FORK_NOJOB) == 0) {
+               close(pip[0]);
+               signal(SIGINT, SIG_IGN);
+               signal(SIGQUIT, SIG_IGN);
+               signal(SIGHUP, SIG_IGN);
+#ifdef SIGTSTP
+               signal(SIGTSTP, SIG_IGN);
+#endif
+               signal(SIGPIPE, SIG_DFL);
+               if (redir->type == NHERE)
+                       full_write(pip[1], redir->nhere.doc->narg.text, len);
+               else
+                       expandhere(redir->nhere.doc, pip[1]);
+               _exit(0);
+       }
+out:
+       close(pip[1]);
+       return pip[0];
+}
+
+static int
+openredirect(union node *redir)
+{
+       char *fname;
+       int f;
+
+       switch (redir->nfile.type) {
+       case NFROM:
+               fname = redir->nfile.expfname;
+               if ((f = open(fname, O_RDONLY)) < 0)
+                       goto eopen;
+               break;
+       case NFROMTO:
+               fname = redir->nfile.expfname;
+               if ((f = open(fname, O_RDWR|O_CREAT|O_TRUNC, 0666)) < 0)
+                       goto ecreate;
+               break;
+       case NTO:
+               /* Take care of noclobber mode. */
+               if (Cflag) {
+                       fname = redir->nfile.expfname;
+                       if ((f = noclobberopen(fname)) < 0)
+                               goto ecreate;
+                       break;
+               }
+               /* FALLTHROUGH */
+       case NCLOBBER:
+               fname = redir->nfile.expfname;
+               if ((f = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666)) < 0)
+                       goto ecreate;
+               break;
+       case NAPPEND:
+               fname = redir->nfile.expfname;
+               if ((f = open(fname, O_WRONLY|O_CREAT|O_APPEND, 0666)) < 0)
+                       goto ecreate;
+               break;
+       default:
+#ifdef DEBUG
+               abort();
+#endif
+               /* Fall through to eliminate warning. */
+       case NTOFD:
+       case NFROMFD:
+               f = -1;
+               break;
+       case NHERE:
+       case NXHERE:
+               f = openhere(redir);
+               break;
+       }
+
+       return f;
+ecreate:
+       sh_error("cannot create %s: %s", fname, errmsg(errno, E_CREAT));
+eopen:
+       sh_error("cannot open %s: %s", fname, errmsg(errno, E_OPEN));
+}
+
+static inline void
+dupredirect(union node *redir, int f)
+{
+       int fd = redir->nfile.fd;
+
+       if (redir->nfile.type == NTOFD || redir->nfile.type == NFROMFD) {
+               if (redir->ndup.dupfd >= 0) {   /* if not ">&-" */
+                               copyfd(redir->ndup.dupfd, fd);
+               }
+               return;
+       }
+
+       if (f != fd) {
+               copyfd(f, fd);
+               close(f);
+       }
+       return;
+}
+
+/*
+ * Process a list of redirection commands.  If the REDIR_PUSH flag is set,
+ * old file descriptors are stashed away so that the redirection can be
+ * undone by calling popredir.  If the REDIR_BACKQ flag is set, then the
+ * standard output, and the standard error if it becomes a duplicate of
+ * stdout, is saved in memory.
+ */
+
+static void
+redirect(union node *redir, int flags)
+{
+       union node *n;
+       struct redirtab *sv;
+       int i;
+       int fd;
+       int newfd;
+       int *p;
+       nullredirs++;
+       if (!redir) {
+               return;
+       }
+       sv = NULL;
+       INTOFF;
+       if (flags & REDIR_PUSH) {
+               struct redirtab *q;
+               q = ckmalloc(sizeof (struct redirtab));
+               q->next = redirlist;
+               redirlist = q;
+               q->nullredirs = nullredirs - 1;
+               for (i = 0 ; i < 10 ; i++)
+                       q->renamed[i] = EMPTY;
+               nullredirs = 0;
+               sv = q;
+       }
+       n = redir;
+       do {
+               fd = n->nfile.fd;
+               if ((n->nfile.type == NTOFD || n->nfile.type == NFROMFD) &&
+                   n->ndup.dupfd == fd)
+                       continue; /* redirect from/to same file descriptor */
+
+               newfd = openredirect(n);
+               if (fd == newfd)
+                       continue;
+               if (sv && *(p = &sv->renamed[fd]) == EMPTY) {
+                       i = fcntl(fd, F_DUPFD, 10);
+
+                       if (i == -1) {
+                               i = errno;
+                               if (i != EBADF) {
+                                       close(newfd);
+                                       errno = i;
+                                       sh_error("%d: %m", fd);
+                                       /* NOTREACHED */
+                               }
+                       } else {
+                               *p = i;
+                               close(fd);
+                       }
+               } else {
+                       close(fd);
+               }
+               dupredirect(n, newfd);
+       } while ((n = n->nfile.next));
+       INTON;
+       if (flags & REDIR_SAVEFD2 && sv && sv->renamed[2] >= 0)
+               preverrout_fd = sv->renamed[2];
+}
+
+
+/*
+ * Undo the effects of the last redirection.
+ */
+
+void
+popredir(int drop)
+{
+       struct redirtab *rp;
+       int i;
+
+       if (--nullredirs >= 0)
+               return;
+       INTOFF;
+       rp = redirlist;
+       for (i = 0 ; i < 10 ; i++) {
+               if (rp->renamed[i] != EMPTY) {
+                       if (!drop) {
+                               close(i);
+                               copyfd(rp->renamed[i], i);
+                       }
+                       close(rp->renamed[i]);
+               }
+       }
+       redirlist = rp->next;
+       nullredirs = rp->nullredirs;
+       ckfree(rp);
+       INTON;
+}
+
+/*
+ * Undo all redirections.  Called on error or interrupt.
+ */
+
+/*
+ * Discard all saved file descriptors.
+ */
+
+void
+clearredir(int drop)
+{
+       for (;;) {
+               nullredirs = 0;
+               if (!redirlist)
+                       break;
+               popredir(drop);
+       }
+}
+
+
+/*
+ * Copy a file descriptor to be >= to.  Returns -1
+ * if the source file descriptor is closed, EMPTY if there are no unused
+ * file descriptors left.
+ */
+
+int
+copyfd(int from, int to)
+{
+       int newfd;
+
+       newfd = fcntl(from, F_DUPFD, to);
+       if (newfd < 0) {
+               if (errno == EMFILE)
+                       return EMPTY;
+               else
+                       sh_error("%d: %m", from);
+       }
+       return newfd;
+}
+
+
+int
+redirectsafe(union node *redir, int flags)
+{
+       int err;
+       volatile int saveint;
+       struct jmploc *volatile savehandler = handler;
+       struct jmploc jmploc;
+
+       SAVEINT(saveint);
+       if (!(err = setjmp(jmploc.loc) * 2)) {
+               handler = &jmploc;
+               redirect(redir, flags);
+       }
+       handler = savehandler;
+       if (err && exception != EXERROR)
+               longjmp(handler->loc, 1);
+       RESTOREINT(saveint);
+       return err;
+}
+
+/*      show.c    */
+
+#ifdef DEBUG
+static void shtree(union node *, int, char *, FILE*);
+static void shcmd(union node *, FILE *);
+static void sharg(union node *, FILE *);
+static void indent(int, char *, FILE *);
+static void trstring(char *);
+
+
+void
+showtree(union node *n)
+{
+       trputs("showtree called\n");
+       shtree(n, 1, NULL, stdout);
+}
+
+
+static void
+shtree(union node *n, int ind, char *pfx, FILE *fp)
+{
+       struct nodelist *lp;
+       const char *s;
+
+       if (n == NULL)
+               return;
+
+       indent(ind, pfx, fp);
+       switch(n->type) {
+       case NSEMI:
+               s = "; ";
+               goto binop;
+       case NAND:
+               s = " && ";
+               goto binop;
+       case NOR:
+               s = " || ";
+binop:
+               shtree(n->nbinary.ch1, ind, NULL, fp);
+          /*    if (ind < 0) */
+                       fputs(s, fp);
+               shtree(n->nbinary.ch2, ind, NULL, fp);
+               break;
+       case NCMD:
+               shcmd(n, fp);
+               if (ind >= 0)
+                       putc('\n', fp);
+               break;
+       case NPIPE:
+               for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
+                       shcmd(lp->n, fp);
+                       if (lp->next)
+                               fputs(" | ", fp);
+               }
+               if (n->npipe.backgnd)
+                       fputs(" &", fp);
+               if (ind >= 0)
+                       putc('\n', fp);
+               break;
+       default:
+               fprintf(fp, "<node type %d>", n->type);
+               if (ind >= 0)
+                       putc('\n', fp);
+               break;
+       }
+}
+
+
+static void
+shcmd(union node *cmd, FILE *fp)
+{
+       union node *np;
+       int first;
+       const char *s;
+       int dftfd;
+
+       first = 1;
+       for (np = cmd->ncmd.args ; np ; np = np->narg.next) {
+               if (! first)
+                       putchar(' ');
+               sharg(np, fp);
+               first = 0;
+       }
+       for (np = cmd->ncmd.redirect ; np ; np = np->nfile.next) {
+               if (! first)
+                       putchar(' ');
+               switch (np->nfile.type) {
+                       case NTO:       s = ">";  dftfd = 1; break;
+                       case NCLOBBER:  s = ">|"; dftfd = 1; break;
+                       case NAPPEND:   s = ">>"; dftfd = 1; break;
+                       case NTOFD:     s = ">&"; dftfd = 1; break;
+                       case NFROM:     s = "<";  dftfd = 0; break;
+                       case NFROMFD:   s = "<&"; dftfd = 0; break;
+                       case NFROMTO:   s = "<>"; dftfd = 0; break;
+                       default:        s = "*error*"; dftfd = 0; break;
+               }
+               if (np->nfile.fd != dftfd)
+                       fprintf(fp, "%d", np->nfile.fd);
+               fputs(s, fp);
+               if (np->nfile.type == NTOFD || np->nfile.type == NFROMFD) {
+                       fprintf(fp, "%d", np->ndup.dupfd);
+               } else {
+                       sharg(np->nfile.fname, fp);
+               }
+               first = 0;
+       }
+}
+
+
+
+static void
+sharg(union node *arg, FILE *fp)
+{
+       char *p;
+       struct nodelist *bqlist;
+       int subtype;
+
+       if (arg->type != NARG) {
+               out1fmt("<node type %d>\n", arg->type);
+               abort();
+       }
+       bqlist = arg->narg.backquote;
+       for (p = arg->narg.text ; *p ; p++) {
+               switch (*p) {
+               case CTLESC:
+                       putc(*++p, fp);
+                       break;
+               case CTLVAR:
+                       putc('$', fp);
+                       putc('{', fp);
+                       subtype = *++p;
+                       if (subtype == VSLENGTH)
+                               putc('#', fp);
+
+                       while (*p != '=')
+                               putc(*p++, fp);
+
+                       if (subtype & VSNUL)
+                               putc(':', fp);
+
+                       switch (subtype & VSTYPE) {
+                       case VSNORMAL:
+                               putc('}', fp);
+                               break;
+                       case VSMINUS:
+                               putc('-', fp);
+                               break;
+                       case VSPLUS:
+                               putc('+', fp);
+                               break;
+                       case VSQUESTION:
+                               putc('?', fp);
+                               break;
+                       case VSASSIGN:
+                               putc('=', fp);
+                               break;
+                       case VSTRIMLEFT:
+                               putc('#', fp);
+                               break;
+                       case VSTRIMLEFTMAX:
+                               putc('#', fp);
+                               putc('#', fp);
+                               break;
+                       case VSTRIMRIGHT:
+                               putc('%', fp);
+                               break;
+                       case VSTRIMRIGHTMAX:
+                               putc('%', fp);
+                               putc('%', fp);
+                               break;
+                       case VSLENGTH:
+                               break;
+                       default:
+                               out1fmt("<subtype %d>", subtype);
+                       }
+                       break;
+               case CTLENDVAR:
+                    putc('}', fp);
+                    break;
+               case CTLBACKQ:
+               case CTLBACKQ|CTLQUOTE:
+                       putc('$', fp);
+                       putc('(', fp);
+                       shtree(bqlist->n, -1, NULL, fp);
+                       putc(')', fp);
+                       break;
+               default:
+                       putc(*p, fp);
+                       break;
+               }
+       }
+}
+
+
+static void
+indent(int amount, char *pfx, FILE *fp)
+{
+       int i;
+
+       for (i = 0 ; i < amount ; i++) {
+               if (pfx && i == amount - 1)
+                       fputs(pfx, fp);
+               putc('\t', fp);
+       }
+}
+
+
+
+/*
+ * Debugging stuff.
+ */
+
+
+FILE *tracefile;
+
+
+void
+trputc(int c)
+{
+       if (debug != 1)
+               return;
+       putc(c, tracefile);
+}
+
+void
+trace(const char *fmt, ...)
+{
+       va_list va;
+
+       if (debug != 1)
+               return;
+       va_start(va, fmt);
+       (void) vfprintf(tracefile, fmt, va);
+       va_end(va);
+}
+
+void
+tracev(const char *fmt, va_list va)
+{
+       if (debug != 1)
+               return;
+       (void) vfprintf(tracefile, fmt, va);
+}
+
+
+void
+trputs(const char *s)
+{
+       if (debug != 1)
+               return;
+       fputs(s, tracefile);
+}
+
+
+static void
+trstring(char *s)
+{
+       char *p;
+       char c;
+
+       if (debug != 1)
+               return;
+       putc('"', tracefile);
+       for (p = s ; *p ; p++) {
+               switch (*p) {
+               case '\n':  c = 'n';  goto backslash;
+               case '\t':  c = 't';  goto backslash;
+               case '\r':  c = 'r';  goto backslash;
+               case '"':  c = '"';  goto backslash;
+               case '\\':  c = '\\';  goto backslash;
+               case CTLESC:  c = 'e';  goto backslash;
+               case CTLVAR:  c = 'v';  goto backslash;
+               case CTLVAR+CTLQUOTE:  c = 'V';  goto backslash;
+               case CTLBACKQ:  c = 'q';  goto backslash;
+               case CTLBACKQ+CTLQUOTE:  c = 'Q';  goto backslash;
+backslash:        putc('\\', tracefile);
+                       putc(c, tracefile);
+                       break;
+               default:
+                       if (*p >= ' ' && *p <= '~')
+                               putc(*p, tracefile);
+                       else {
+                               putc('\\', tracefile);
+                               putc(*p >> 6 & 03, tracefile);
+                               putc(*p >> 3 & 07, tracefile);
+                               putc(*p & 07, tracefile);
+                       }
+                       break;
+               }
+       }
+       putc('"', tracefile);
 }
 
-/*
- * Parse an arithmetic expansion (indicate start of one and set state)
- */
-parsearith: {
 
-       if (++arinest == 1) {
-               prevsyntax = syntax;
-               syntax = ARISYNTAX;
-               USTPUTC(CTLARI, out);
-               if (dblquote)
-                       USTPUTC('"',out);
+void
+trargs(char **ap)
+{
+       if (debug != 1)
+               return;
+       while (*ap) {
+               trstring(*ap++);
+               if (*ap)
+                       putc(' ', tracefile);
                else
-                       USTPUTC(' ',out);
-       } else {
-               /*
-                * we collapse embedded arithmetic expansion to
-                * parenthesis, which should be equivalent
-                */
-               USTPUTC('(', out);
+                       putc('\n', tracefile);
        }
-       goto parsearith_return;
 }
 
-} /* end of readtoken */
-
-
-/*
- * Returns true if the text contains nothing to expand (no dollar signs
- * or backquotes).
- */
 
-static int
-noexpand(char *text)
+void
+opentrace(void)
 {
-       char *p;
-       char c;
+       char s[100];
+#ifdef O_APPEND
+       int flags;
+#endif
 
-       p = text;
-       while ((c = *p++) != '\0') {
-               if (c == CTLQUOTEMARK)
-                       continue;
-               if (c == CTLESC)
-                       p++;
-               else if (SIT(c,BASESYNTAX) == CCTL)
-                       return 0;
+       if (debug != 1) {
+               if (tracefile)
+                       fflush(tracefile);
+               /* leave open because libedit might be using it */
+               return;
        }
-       return 1;
+       scopy("./trace", s);
+       if (tracefile) {
+               if (!freopen(s, "a", tracefile)) {
+                       fprintf(stderr, "Can't re-open %s\n", s);
+                       debug = 0;
+                       return;
+               }
+       } else {
+               if ((tracefile = fopen(s, "a")) == NULL) {
+                       fprintf(stderr, "Can't open %s\n", s);
+                       debug = 0;
+                       return;
+               }
+       }
+#ifdef O_APPEND
+       if ((flags = fcntl(fileno(tracefile), F_GETFL, 0)) >= 0)
+               fcntl(fileno(tracefile), F_SETFL, flags | O_APPEND);
+#endif
+       setlinebuf(tracefile);
+       fputs("\nTracing started.\n", tracefile);
 }
+#endif /* DEBUG */
 
 
+/*      trap.c       */
+
 /*
- * Return true if the argument is a legal variable name (a letter or
- * underscore followed by zero or more letters, underscores, and digits).
+ * Sigmode records the current value of the signal handlers for the various
+ * modes.  A value of zero means that the current handler is not known.
+ * S_HARD_IGN indicates that the signal was ignored on entry to the shell,
  */
 
-static int
-goodname(const char *name)
-{
-       const char *p;
+#define S_DFL 1                 /* default signal handling (SIG_DFL) */
+#define S_CATCH 2               /* signal is caught */
+#define S_IGN 3                 /* signal is ignored (SIG_IGN) */
+#define S_HARD_IGN 4            /* signal is ignored permenantly */
+#define S_RESET 5               /* temporary - to reset a hard ignored sig */
 
-       p = name;
-       if (! is_name(*p))
-               return 0;
-       while (*++p) {
-               if (! is_in_name(*p))
-                       return 0;
-       }
-       return 1;
-}
 
 
 /*
- * Called when an unexpected token is read during the parse.  The argument
- * is the token that is expected, or -1 if more than one type of token can
- * occur at this point.
+ * The trap builtin.
  */
 
-static void
-synexpect(int token)
+int
+trapcmd(int argc, char **argv)
 {
-       char msg[64];
-       int l;
-
-       l = sprintf(msg, "%s unexpected", tokname(lasttoken));
-       if (token >= 0)
-               sprintf(msg+l, " (expecting %s)", tokname(token));
-       synerror(msg);
-       /* NOTREACHED */
-}
+       char *action;
+       char **ap;
+       int signo;
 
+       nextopt(nullstr);
+       ap = argptr;
+       if (!*ap) {
+               for (signo = 0 ; signo < NSIG ; signo++) {
+                       if (trap[signo] != NULL) {
+                               const char *sn;
 
-static void
-synerror(const char *msg)
-{
-       if (commandname)
-               out2fmt("%s: %d: ", commandname, startlinno);
-       out2fmt("Syntax error: %s\n", msg);
-       error((char *)NULL);
-       /* NOTREACHED */
+                               sn = get_signame(signo);
+                               out1fmt("trap -- %s %s\n",
+                                       single_quote(trap[signo]), sn);
+                       }
+               }
+               return 0;
+       }
+       if (!ap[1])
+               action = NULL;
+       else
+               action = *ap++;
+       while (*ap) {
+               if ((signo = get_signum(*ap)) < 0)
+                       sh_error("%s: bad trap", *ap);
+               INTOFF;
+               if (action) {
+                       if (action[0] == '-' && action[1] == '\0')
+                               action = NULL;
+                       else
+                               action = savestr(action);
+               }
+               if (trap[signo])
+                       ckfree(trap[signo]);
+               trap[signo] = action;
+               if (signo != 0)
+                       setsignal(signo);
+               INTON;
+               ap++;
+       }
+       return 0;
 }
 
 
 /*
- * called by editline -- any expansions to the prompt
- *    should be added here.
+ * Clear traps on a fork.
  */
-static void
-setprompt(int whichprompt)
+
+void
+clear_traps(void)
 {
-    char *prompt;
-    switch (whichprompt) {
-       case 1:
-               prompt = ps1val();
-               break;
-       case 2:
-               prompt = ps2val();
-               break;
-       default:                /* 0 */
-               prompt = "";
-    }
-    putprompt(prompt);
+       char **tp;
+
+       for (tp = trap ; tp < &trap[NSIG] ; tp++) {
+               if (*tp && **tp) {      /* trap not NULL or SIG_IGN */
+                       INTOFF;
+                       ckfree(*tp);
+                       *tp = NULL;
+                       if (tp != &trap[0])
+                               setsignal(tp - trap);
+                       INTON;
+               }
+       }
 }
 
 
 /*
- * Code for dealing with input/output redirection.
+ * Set the signal handler for the specified signal.  The routine figures
+ * out what it should be set to.
  */
 
-#define EMPTY -2                /* marks an unused slot in redirtab */
-#ifndef PIPE_BUF
-# define PIPESIZE 4096          /* amount of buffering in a pipe */
-#else
-# define PIPESIZE PIPE_BUF
-#endif
-
-
-/*
- * Open a file in noclobber mode.
- * The code was copied from bash.
- */
-static inline int
-noclobberopen(const char *fname)
+void
+setsignal(int signo)
 {
-       int r, fd;
-       struct stat finfo, finfo2;
+       int action;
+       char *t, tsig;
+       struct sigaction act;
 
-       /*
-        * If the file exists and is a regular file, return an error
-        * immediately.
-        */
-       r = stat(fname, &finfo);
-       if (r == 0 && S_ISREG(finfo.st_mode)) {
-               errno = EEXIST;
-               return -1;
+       if ((t = trap[signo]) == NULL)
+               action = S_DFL;
+       else if (*t != '\0')
+               action = S_CATCH;
+       else
+               action = S_IGN;
+       if (rootshell && action == S_DFL) {
+               switch (signo) {
+               case SIGINT:
+                       if (iflag || minusc || sflag == 0)
+                               action = S_CATCH;
+                       break;
+               case SIGQUIT:
+#ifdef DEBUG
+                       if (debug)
+                               break;
+#endif
+                       /* FALLTHROUGH */
+               case SIGTERM:
+                       if (iflag)
+                               action = S_IGN;
+                       break;
+#if JOBS
+               case SIGTSTP:
+               case SIGTTOU:
+                       if (mflag)
+                               action = S_IGN;
+                       break;
+#endif
+               }
        }
 
-       /*
-        * If the file was not present (r != 0), make sure we open it
-        * exclusively so that if it is created before we open it, our open
-        * will fail.  Make sure that we do not truncate an existing file.
-        * Note that we don't turn on O_EXCL unless the stat failed -- if the
-        * file was not a regular file, we leave O_EXCL off.
-        */
-       if (r != 0)
-               return open(fname, O_WRONLY|O_CREAT|O_EXCL, 0666);
-       fd = open(fname, O_WRONLY|O_CREAT, 0666);
-
-       /* If the open failed, return the file descriptor right away. */
-       if (fd < 0)
-               return fd;
-
-       /*
-        * OK, the open succeeded, but the file may have been changed from a
-        * non-regular file to a regular file between the stat and the open.
-        * We are assuming that the O_EXCL open handles the case where FILENAME
-        * did not exist and is symlinked to an existing file between the stat
-        * and open.
-        */
+       t = &sigmode[signo - 1];
+       tsig = *t;
+       if (tsig == 0) {
+               /*
+                * current setting unknown
+                */
+               if (sigaction(signo, 0, &act) == -1) {
+                       /*
+                        * Pretend it worked; maybe we should give a warning
+                        * here, but other shells don't. We don't alter
+                        * sigmode, so that we retry every time.
+                        */
+                       return;
+               }
+               if (act.sa_handler == SIG_IGN) {
+                       if (mflag && (signo == SIGTSTP ||
+                            signo == SIGTTIN || signo == SIGTTOU)) {
+                               tsig = S_IGN;   /* don't hard ignore these */
+                       } else
+                               tsig = S_HARD_IGN;
+               } else {
+                       tsig = S_RESET; /* force to be set */
+               }
+       }
+       if (tsig == S_HARD_IGN || tsig == action)
+               return;
+       switch (action) {
+       case S_CATCH:
+               act.sa_handler = onsig;
+               break;
+       case S_IGN:
+               act.sa_handler = SIG_IGN;
+               break;
+       default:
+               act.sa_handler = SIG_DFL;
+       }
+       *t = action;
+       act.sa_flags = 0;
+       sigfillset(&act.sa_mask);
+       sigaction(signo, &act, 0);
+}
 
-       /*
-        * If we can open it and fstat the file descriptor, and neither check
-        * revealed that it was a regular file, and the file has not been
-        * replaced, return the file descriptor.
-        */
-        if (fstat(fd, &finfo2) == 0 && !S_ISREG(finfo2.st_mode) &&
-            finfo.st_dev == finfo2.st_dev && finfo.st_ino == finfo2.st_ino)
-               return fd;
+/*
+ * Ignore a signal.
+ */
 
-       /* The file has been replaced.  badness. */
-       close(fd);
-       errno = EEXIST;
-       return -1;
+void
+ignoresig(int signo)
+{
+       if (sigmode[signo - 1] != S_IGN && sigmode[signo - 1] != S_HARD_IGN) {
+               signal(signo, SIG_IGN);
+       }
+       sigmode[signo - 1] = S_HARD_IGN;
 }
 
+
 /*
- * Handle here documents.  Normally we fork off a process to write the
- * data to a pipe.  If the document is short, we can stuff the data in
- * the pipe without forking.
+ * Signal handler.
  */
 
-static inline int
-openhere(const union node *redir)
+void
+onsig(int signo)
 {
-       int pip[2];
-       int len = 0;
+       gotsig[signo - 1] = 1;
+       pendingsigs = signo;
 
-       if (pipe(pip) < 0)
-               error("Pipe call failed");
-       if (redir->type == NHERE) {
-               len = strlen(redir->nhere.doc->narg.text);
-               if (len <= PIPESIZE) {
-                       xwrite(pip[1], redir->nhere.doc->narg.text, len);
-                       goto out;
-               }
-       }
-       if (forkshell((struct job *)NULL, (union node *)NULL, FORK_NOJOB) == 0) {
-               close(pip[0]);
-               signal(SIGINT, SIG_IGN);
-               signal(SIGQUIT, SIG_IGN);
-               signal(SIGHUP, SIG_IGN);
-#ifdef SIGTSTP
-               signal(SIGTSTP, SIG_IGN);
-#endif
-               signal(SIGPIPE, SIG_DFL);
-               if (redir->type == NHERE)
-                       xwrite(pip[1], redir->nhere.doc->narg.text, len);
-               else
-                       expandhere(redir->nhere.doc, pip[1]);
-               _exit(0);
+       if (exsig || (signo == SIGINT && !trap[SIGINT])) {
+               if (!suppressint)
+                       onint();
+               intpending = 1;
        }
-out:
-       close(pip[1]);
-       return pip[0];
 }
 
 
-static inline int
-openredirect(const union node *redir)
+/*
+ * Called to execute a trap.  Perhaps we should avoid entering new trap
+ * handlers while we are executing a trap handler.
+ */
+
+int
+dotrap(void)
 {
-       char *fname;
-       int f;
+       char *p;
+       char *q;
+       int i;
+       int savestatus;
+       int skip = 0;
 
-       switch (redir->nfile.type) {
-       case NFROM:
-               fname = redir->nfile.expfname;
-               if ((f = open(fname, O_RDONLY)) < 0)
-                       goto eopen;
-               break;
-       case NFROMTO:
-               fname = redir->nfile.expfname;
-               if ((f = open(fname, O_RDWR|O_CREAT|O_TRUNC, 0666)) < 0)
-                       goto ecreate;
-               break;
-       case NTO:
-               /* Take care of noclobber mode. */
-               if (Cflag) {
-                       fname = redir->nfile.expfname;
-                       if ((f = noclobberopen(fname)) < 0)
-                               goto ecreate;
+       savestatus = exitstatus;
+       pendingsigs = 0;
+       xbarrier();
+
+       for (i = 0, q = gotsig; i < NSIG - 1; i++, q++) {
+               if (!*q)
+                       continue;
+               *q = 0;
+
+               p = trap[i + 1];
+               if (!p)
+                       continue;
+               skip = evalstring(p, SKIPEVAL);
+               exitstatus = savestatus;
+               if (skip)
                        break;
-               }
-       case NTOOV:
-               fname = redir->nfile.expfname;
-#ifdef O_CREAT
-               if ((f = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666)) < 0)
-                       goto ecreate;
-#else
-               if ((f = creat(fname, 0666)) < 0)
-                       goto ecreate;
-#endif
-               break;
-       case NAPPEND:
-               fname = redir->nfile.expfname;
-#ifdef O_APPEND
-               if ((f = open(fname, O_WRONLY|O_CREAT|O_APPEND, 0666)) < 0)
-                       goto ecreate;
-#else
-               if ((f = open(fname, O_WRONLY)) < 0
-                && (f = creat(fname, 0666)) < 0)
-                       goto ecreate;
-               lseek(f, (off_t)0, 2);
-#endif
-               break;
-       default:
-#ifdef DEBUG
-               abort();
-#endif
-               /* Fall through to eliminate warning. */
-       case NTOFD:
-       case NFROMFD:
-               f = -1;
-               break;
-       case NHERE:
-       case NXHERE:
-               f = openhere(redir);
-               break;
        }
 
-       return f;
-ecreate:
-       error("cannot create %s: %s", fname, errmsg(errno, E_CREAT));
-eopen:
-       error("cannot open %s: %s", fname, errmsg(errno, E_OPEN));
+       return skip;
 }
 
 
 /*
- * Process a list of redirection commands.  If the REDIR_PUSH flag is set,
- * old file descriptors are stashed away so that the redirection can be
- * undone by calling popredir.  If the REDIR_BACKQ flag is set, then the
- * standard output, and the standard error if it becomes a duplicate of
- * stdout.
+ * Controls whether the shell is interactive or not.
  */
 
-static void
-redirect(union node *redir, int flags)
+void
+setinteractive(int on)
 {
-       union node *n;
-       struct redirtab *sv = NULL;
-       int i;
-       int fd;
-       int newfd;
-       int try;
-       int fd1dup = flags & REDIR_BACKQ;; /* stdout `cmd` redir to pipe */
+       static int is_interactive;
 
-       if (flags & REDIR_PUSH) {
-               sv = xmalloc(sizeof (struct redirtab));
-               for (i = 0 ; i < 10 ; i++)
-                       sv->renamed[i] = EMPTY;
-               sv->next = redirlist;
-               redirlist = sv;
+       if (++on == is_interactive)
+               return;
+       is_interactive = on;
+       setsignal(SIGINT);
+       setsignal(SIGQUIT);
+       setsignal(SIGTERM);
+#ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
+               if(is_interactive > 1) {
+                       /* Looks like they want an interactive shell */
+                       static int do_banner;
+
+                               if(!do_banner) {
+                                       out1fmt(
+                       "\n\n%s Built-in shell (ash)\n"
+                       "Enter 'help' for a list of built-in commands.\n\n",
+                                       BB_BANNER);
+                                       do_banner++;
+                               }
+               }
+#endif
+}
+
+
+#ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
+/*** List the available builtins ***/
+
+static int helpcmd(int argc, char **argv)
+{
+       int col, i;
+
+       out1fmt("\nBuilt-in commands:\n-------------------\n");
+       for (col = 0, i = 0; i < NUMBUILTINS; i++) {
+               col += out1fmt("%c%s", ((col == 0) ? '\t' : ' '),
+                                         builtincmd[i].name + 1);
+               if (col > 60) {
+                       out1fmt("\n");
+                       col = 0;
+               }
        }
-       for (n = redir ; n ; n = n->nfile.next) {
-               fd = n->nfile.fd;
-               try = 0;
-               if ((n->nfile.type == NTOFD || n->nfile.type == NFROMFD) &&
-                   n->ndup.dupfd == fd)
-                       continue; /* redirect from/to same file descriptor */
+#ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
+       {
+               extern const struct BB_applet applets[];
+               extern const size_t NUM_APPLETS;
 
-               INTOFF;
-               newfd = openredirect(n);
-               if ((flags & REDIR_PUSH) && sv->renamed[fd] == EMPTY) {
-                       if (newfd == fd) {
-                               try++;
-                       } else if ((i = fcntl(fd, F_DUPFD, 10)) == -1) {
-                               switch (errno) {
-                               case EBADF:
-                                       if (!try) {
-                                               dupredirect(n, newfd, fd1dup);
-                                               try++;
-                                               break;
-                                       }
-                                       /* FALLTHROUGH*/
-                               default:
-                                       if (newfd >= 0) {
-                                               close(newfd);
-                                       }
-                                       INTON;
-                                       error("%d: %m", fd);
-                                       /* NOTREACHED */
-                               }
-                       }
-                       if (!try) {
-                               close(fd);
-                               if (flags & REDIR_PUSH) {
-                                       sv->renamed[fd] = i;
-                               }
+               for (i = 0; i < NUM_APPLETS; i++) {
+
+                       col += out1fmt("%c%s", ((col == 0) ? '\t' : ' '), applets[i].name);
+                       if (col > 60) {
+                               out1fmt("\n");
+                               col = 0;
                        }
-               } else if (fd != newfd) {
-                       close(fd);
                }
-               if (fd == 0)
-                       fd0_redirected++;
-               if (!try)
-                       dupredirect(n, newfd, fd1dup);
-               INTON;
        }
+#endif
+       out1fmt("\n\n");
+       return EXIT_SUCCESS;
 }
+#endif /* CONFIG_FEATURE_SH_EXTRA_QUIET */
 
+/*
+ * Called to exit the shell.
+ */
 
-static void
-dupredirect(const union node *redir, int f, int fd1dup)
+void
+exitshell(void)
 {
-       int fd = redir->nfile.fd;
+       struct jmploc loc;
+       char *p;
+       int status;
 
-       if(fd==1)
-               fd1dup = 0;
-       if (redir->nfile.type == NTOFD || redir->nfile.type == NFROMFD) {
-               if (redir->ndup.dupfd >= 0) {   /* if not ">&-" */
-                       if (redir->ndup.dupfd!=1 || fd1dup!=1)
-                               dup_as_newfd(redir->ndup.dupfd, fd);
-               }
-               return;
+       status = exitstatus;
+       TRACE(("pid %d, exitshell(%d)\n", getpid(), status));
+       if (setjmp(loc.loc)) {
+               if (exception == EXEXIT)
+                       _exit(exitstatus);
+               goto out;
+       }
+       handler = &loc;
+       if ((p = trap[0])) {
+               trap[0] = NULL;
+               evalstring(p, 0);
        }
+       flushall();
+       setjobctl(0);
+#ifdef CONFIG_FEATURE_COMMAND_SAVEHISTORY
+       if (iflag && rootshell) {
+               const char *hp = lookupvar("HISTFILE");
 
-       if (f != fd) {
-               dup_as_newfd(f, fd);
-               close(f);
+               if(hp != NULL )
+                       save_history ( hp );
        }
-       return;
+#endif
+out:
+       _exit(status);
+       /* NOTREACHED */
 }
 
+/*      var.c     */
+
+static struct var *vartab[VTABSIZE];
 
+static int vpcmp(const void *, const void *);
+static struct var **findvar(struct var **, const char *);
 
 /*
- * Undo the effects of the last redirection.
+ * Initialize the variable symbol tables and import the environment
  */
 
-static void
-popredir(void)
+
+#ifdef CONFIG_ASH_GETOPTS
+/*
+ * Safe version of setvar, returns 1 on success 0 on failure.
+ */
+
+int
+setvarsafe(const char *name, const char *val, int flags)
 {
-       struct redirtab *rp = redirlist;
-       int i;
+       int err;
+       volatile int saveint;
+       struct jmploc *volatile savehandler = handler;
+       struct jmploc jmploc;
 
-       INTOFF;
-       for (i = 0 ; i < 10 ; i++) {
-               if (rp->renamed[i] != EMPTY) {
-                       if (i == 0)
-                               fd0_redirected--;
-                       close(i);
-                       if (rp->renamed[i] >= 0) {
-                               dup_as_newfd(rp->renamed[i], i);
-                               close(rp->renamed[i]);
-                       }
-               }
+       SAVEINT(saveint);
+       if (setjmp(jmploc.loc))
+               err = 1;
+       else {
+               handler = &jmploc;
+               setvar(name, val, flags);
+               err = 0;
        }
-       redirlist = rp->next;
-       ckfree(rp);
-       INTON;
+       handler = savehandler;
+       RESTOREINT(saveint);
+       return err;
 }
+#endif
 
 /*
- * Discard all saved file descriptors.
+ * Set the value of a variable.  The flags argument is ored with the
+ * flags of the variable.  If val is NULL, the variable is unset.
  */
 
 static void
-clearredir(void) {
-       struct redirtab *rp;
-       int i;
+setvar(const char *name, const char *val, int flags)
+{
+       char *p, *q;
+       size_t namelen;
+       char *nameeq;
+       size_t vallen;
 
-       for (rp = redirlist ; rp ; rp = rp->next) {
-               for (i = 0 ; i < 10 ; i++) {
-                       if (rp->renamed[i] >= 0) {
-                               close(rp->renamed[i]);
-                       }
-                       rp->renamed[i] = EMPTY;
-               }
+       q = endofname(name);
+       p = strchrnul(q, '=');
+       namelen = p - name;
+       if (!namelen || p != q)
+               sh_error("%.*s: bad variable name", namelen, name);
+       vallen = 0;
+       if (val == NULL) {
+               flags |= VUNSET;
+       } else {
+               vallen = strlen(val);
        }
+       INTOFF;
+       p = mempcpy(nameeq = ckmalloc(namelen + vallen + 2), name, namelen);
+       if (val) {
+               *p++ = '=';
+               p = mempcpy(p, val, vallen);
+       }
+       *p = '\0';
+       setvareq(nameeq, flags | VNOSAVE);
+       INTON;
 }
 
 
 /*
- * Copy a file descriptor to be >= to.  Returns -1
- * if the source file descriptor is closed, EMPTY if there are no unused
- * file descriptors left.
+ * Same as setvar except that the variable and value are passed in
+ * the first argument as name=value.  Since the first argument will
+ * be actually stored in the table, it should not be a string that
+ * will go away.
+ * Called with interrupts off.
  */
 
-static int
-dup_as_newfd(int from, int to)
+void
+setvareq(char *s, int flags)
 {
-       int newfd;
+       struct var *vp, **vpp;
 
-       newfd = fcntl(from, F_DUPFD, to);
-       if (newfd < 0) {
-               if (errno == EMFILE)
-                       return EMPTY;
-               else
-                       error("%d: %m", from);
-       }
-       return newfd;
-}
+       vpp = hashvar(s);
+       flags |= (VEXPORT & (((unsigned) (1 - aflag)) - 1));
+       vp = *findvar(vpp, s);
+       if (vp) {
+               if ((vp->flags & (VREADONLY|VDYNAMIC)) == VREADONLY) {
+                       const char *n;
 
-#ifdef DEBUG
-/*
- * Debugging stuff.
- */
-static void shtree (union node *, int, char *, FILE*);
-static void shcmd (union node *, FILE *);
-static void sharg (union node *, FILE *);
-static void indent (int, char *, FILE *);
-static void trstring (char *);
+                       if (flags & VNOSAVE)
+                               free(s);
+                       n = vp->text;
+                       sh_error("%.*s: is read only", strchrnul(n, '=') - n, n);
+               }
 
+               if (flags & VNOSET)
+                       return;
 
-static void
-showtree(n)
-       unode *n;
-{
-       trputs("showtree called\n");
-       shtree(n, 1, NULL, stdout);
+               if (vp->func && (flags & VNOFUNC) == 0)
+                       (*vp->func)(strchrnul(s, '=') + 1);
+
+               if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
+                       ckfree(vp->text);
+
+               flags |= vp->flags & ~(VTEXTFIXED|VSTACK|VNOSAVE|VUNSET);
+       } else {
+               if (flags & VNOSET)
+                       return;
+               /* not found */
+               vp = ckmalloc(sizeof (*vp));
+               vp->next = *vpp;
+               vp->func = NULL;
+               *vpp = vp;
+       }
+       if (!(flags & (VTEXTFIXED|VSTACK|VNOSAVE)))
+               s = savestr(s);
+       vp->text = s;
+       vp->flags = flags;
 }
 
 
+/*
+ * Process a linked list of variable assignments.
+ */
+
 static void
-shtree(union node *n, int ind, char *pfx, FILE *fp)
+listsetvar(struct strlist *list_set_var, int flags)
 {
-       struct nodelist *lp;
-       const char *s;
+       struct strlist *lp = list_set_var;
 
-       if (n == NULL)
+       if (!lp)
                return;
-
-       indent(ind, pfx, fp);
-       switch(n->type) {
-       case NSEMI:
-               s = "; ";
-               goto binop;
-       case NAND:
-               s = " && ";
-               goto binop;
-       case NOR:
-               s = " || ";
-binop:
-               shtree(n->nbinary.ch1, ind, NULL, fp);
-          /*    if (ind < 0) */
-                       fputs(s, fp);
-               shtree(n->nbinary.ch2, ind, NULL, fp);
-               break;
-       case NCMD:
-               shcmd(n, fp);
-               if (ind >= 0)
-                       putc('\n', fp);
-               break;
-       case NPIPE:
-               for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
-                       shcmd(lp->n, fp);
-                       if (lp->next)
-                               fputs(" | ", fp);
-               }
-               if (n->npipe.backgnd)
-                       fputs(" &", fp);
-               if (ind >= 0)
-                       putc('\n', fp);
-               break;
-       default:
-               fprintf(fp, "<node type %d>", n->type);
-               if (ind >= 0)
-                       putc('\n', fp);
-               break;
-       }
+       INTOFF;
+       do {
+               setvareq(lp->text, flags);
+       } while ((lp = lp->next));
+       INTON;
 }
 
 
+/*
+ * Find the value of a variable.  Returns NULL if not set.
+ */
 
-static void
-shcmd(union node *cmd, FILE *fp)
+static char *
+lookupvar(const char *name)
 {
-       union node *np;
-       int first;
-       const char *s;
-       int dftfd;
+       struct var *v;
 
-       first = 1;
-       for (np = cmd->ncmd.args ; np ; np = np->narg.next) {
-               if (! first)
-                       putchar(' ');
-               sharg(np, fp);
-               first = 0;
-       }
-       for (np = cmd->ncmd.redirect ; np ; np = np->nfile.next) {
-               if (! first)
-                       putchar(' ');
-#if 1
-               s = "*error*";
-               dftfd = 0;
-               if ((np->nfile.type <= NFROMFD) && (np->nfile.type >= NTO)) {
-                       s = redir_strings[np->nfile.type - NTO];
-                       if (*s == '>') {
-                               dftfd = 1;
-                       }
-               }
-#else
-               switch (np->nfile.type) {
-                       case NTO:       s = ">";  dftfd = 1; break;
-                       case NAPPEND:   s = ">>"; dftfd = 1; break;
-                       case NTOFD:     s = ">&"; dftfd = 1; break;
-                       case NTOOV:     s = ">|"; dftfd = 1; break;
-                       case NFROM:     s = "<";  dftfd = 0; break;
-                       case NFROMFD:   s = "<&"; dftfd = 0; break;
-                       case NFROMTO:   s = "<>"; dftfd = 0; break;
-                       default:        s = "*error*"; dftfd = 0; break;
-               }
+       if ((v = *findvar(hashvar(name), name))) {
+#ifdef DYNAMIC_VAR
+       /*
+        * Dynamic variables are implemented roughly the same way they are
+        * in bash. Namely, they're "special" so long as they aren't unset.
+        * As soon as they're unset, they're no longer dynamic, and dynamic
+        * lookup will no longer happen at that point. -- PFM.
+        */
+               if((v->flags & VDYNAMIC))
+                       (*v->func)(NULL);
 #endif
-               if (np->nfile.fd != dftfd)
-                       fprintf(fp, "%d", np->nfile.fd);
-               fputs(s, fp);
-               if (np->nfile.type == NTOFD || np->nfile.type == NFROMFD) {
-                       fprintf(fp, "%d", np->ndup.dupfd);
-               } else {
-                       sharg(np->nfile.fname, fp);
-               }
-               first = 0;
+               if(!(v->flags & VUNSET))
+                       return strchrnul(v->text, '=') + 1;
        }
+
+       return NULL;
 }
 
-static void
-sharg(union node *arg, FILE *fp)
+
+/*
+ * Search the environment of a builtin command.
+ */
+
+static char *
+bltinlookup(const char *name)
 {
-       char *p;
-       struct nodelist *bqlist;
-       int subtype;
+       struct strlist *sp;
 
-       if (arg->type != NARG) {
-               printf("<node type %d>\n", arg->type);
-               fflush(stdout);
-               abort();
+       for (sp = cmdenviron ; sp ; sp = sp->next) {
+               if (varequal(sp->text, name))
+                       return strchrnul(sp->text, '=') + 1;
        }
-       bqlist = arg->narg.backquote;
-       for (p = arg->narg.text ; *p ; p++) {
-               switch (*p) {
-               case CTLESC:
-                       putc(*++p, fp);
-                       break;
-               case CTLVAR:
-                       putc('$', fp);
-                       putc('{', fp);
-                       subtype = *++p;
-                       if (subtype == VSLENGTH)
-                               putc('#', fp);
+       return lookupvar(name);
+}
 
-                       while (*p != '=')
-                               putc(*p++, fp);
 
-                       if (subtype & VSNUL)
-                               putc(':', fp);
+/*
+ * Generate a list of variables satisfying the given conditions.
+ */
 
-                       switch (subtype & VSTYPE) {
-                       case VSNORMAL:
-                               putc('}', fp);
-                               break;
-                       case VSMINUS:
-                               putc('-', fp);
-                               break;
-                       case VSPLUS:
-                               putc('+', fp);
-                               break;
-                       case VSQUESTION:
-                               putc('?', fp);
-                               break;
-                       case VSASSIGN:
-                               putc('=', fp);
-                               break;
-                       case VSTRIMLEFT:
-                               putc('#', fp);
-                               break;
-                       case VSTRIMLEFTMAX:
-                               putc('#', fp);
-                               putc('#', fp);
-                               break;
-                       case VSTRIMRIGHT:
-                               putc('%', fp);
-                               break;
-                       case VSTRIMRIGHTMAX:
-                               putc('%', fp);
-                               putc('%', fp);
-                               break;
-                       case VSLENGTH:
-                               break;
-                       default:
-                               printf("<subtype %d>", subtype);
-                       }
-                       break;
-               case CTLENDVAR:
-                    putc('}', fp);
-                    break;
-               case CTLBACKQ:
-               case CTLBACKQ|CTLQUOTE:
-                       putc('$', fp);
-                       putc('(', fp);
-                       shtree(bqlist->n, -1, NULL, fp);
-                       putc(')', fp);
-                       break;
-               default:
-                       putc(*p, fp);
-                       break;
-               }
-       }
+static char **
+listvars(int on, int off, char ***end)
+{
+       struct var **vpp;
+       struct var *vp;
+       char **ep;
+       int mask;
+
+       STARTSTACKSTR(ep);
+       vpp = vartab;
+       mask = on | off;
+       do {
+               for (vp = *vpp ; vp ; vp = vp->next)
+                       if ((vp->flags & mask) == on) {
+                               if (ep == stackstrend())
+                                       ep = growstackstr();
+                               *ep++ = (char *) vp->text;
+                       }
+       } while (++vpp < vartab + VTABSIZE);
+       if (ep == stackstrend())
+               ep = growstackstr();
+       if (end)
+               *end = ep;
+       *ep++ = NULL;
+       return grabstackstr(ep);
 }
 
 
-static void
-indent(int amount, char *pfx, FILE *fp)
-{
-       int i;
-
-       for (i = 0 ; i < amount ; i++) {
-               if (pfx && i == amount - 1)
-                       fputs(pfx, fp);
-               putc('\t', fp);
-       }
-}
+/*
+ * POSIX requires that 'set' (but not export or readonly) output the
+ * variables in lexicographic order - by the locale's collating order (sigh).
+ * Maybe we could keep them in an ordered balanced binary tree
+ * instead of hashed lists.
+ * For now just roll 'em through qsort for printing...
+ */
 
+static int
+showvars(const char *sep_prefix, int on, int off)
+{
+       const char *sep;
+       char **ep, **epend;
 
-FILE *tracefile;
+       ep = listvars(on, off, &epend);
+       qsort(ep, epend - ep, sizeof(char *), vpcmp);
 
-#if DEBUG == 2
-static int debug = 1;
-#else
-static int debug = 0;
-#endif
+       sep = *sep_prefix ? spcstr : sep_prefix;
 
+       for (; ep < epend; ep++) {
+               const char *p;
+               const char *q;
 
-static void
-trputc(int c)
-{
-       if (tracefile == NULL)
-               return;
-       putc(c, tracefile);
-       if (c == '\n')
-               fflush(tracefile);
-}
+               p = strchrnul(*ep, '=');
+               q = nullstr;
+               if (*p)
+                       q = single_quote(++p);
 
-static void
-trace(const char *fmt, ...)
-{
-       va_list va;
-       va_start(va, fmt);
-       if (tracefile != NULL) {
-               (void) vfprintf(tracefile, fmt, va);
-               if (strchr(fmt, '\n'))
-                       (void) fflush(tracefile);
+               out1fmt("%s%s%.*s%s\n", sep_prefix, sep, (int)(p - *ep), *ep, q);
        }
-       va_end(va);
+
+       return 0;
 }
 
 
-static void
-trputs(const char *s)
-{
-       if (tracefile == NULL)
-               return;
-       fputs(s, tracefile);
-       if (strchr(s, '\n'))
-               fflush(tracefile);
-}
 
+/*
+ * The export and readonly commands.
+ */
 
-static void
-trstring(char *s)
+static int
+exportcmd(int argc, char **argv)
 {
-       char *p;
-       char c;
+       struct var *vp;
+       char *name;
+       const char *p;
+       char **aptr;
+       int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT;
+       int notp;
 
-       if (tracefile == NULL)
-               return;
-       putc('"', tracefile);
-       for (p = s ; *p ; p++) {
-               switch (*p) {
-               case '\n':  c = 'n';  goto backslash;
-               case '\t':  c = 't';  goto backslash;
-               case '\r':  c = 'r';  goto backslash;
-               case '"':  c = '"';  goto backslash;
-               case '\\':  c = '\\';  goto backslash;
-               case CTLESC:  c = 'e';  goto backslash;
-               case CTLVAR:  c = 'v';  goto backslash;
-               case CTLVAR+CTLQUOTE:  c = 'V';  goto backslash;
-               case CTLBACKQ:  c = 'q';  goto backslash;
-               case CTLBACKQ+CTLQUOTE:  c = 'Q';  goto backslash;
-backslash:        putc('\\', tracefile);
-                       putc(c, tracefile);
-                       break;
-               default:
-                       if (*p >= ' ' && *p <= '~')
-                               putc(*p, tracefile);
-                       else {
-                               putc('\\', tracefile);
-                               putc(*p >> 6 & 03, tracefile);
-                               putc(*p >> 3 & 07, tracefile);
-                               putc(*p & 07, tracefile);
+       notp = nextopt("p") - 'p';
+       if (notp && ((name = *(aptr = argptr)))) {
+               do {
+                       if ((p = strchr(name, '=')) != NULL) {
+                               p++;
+                       } else {
+                               if ((vp = *findvar(hashvar(name), name))) {
+                                       vp->flags |= flag;
+                                       continue;
+                               }
                        }
-                       break;
-               }
+                       setvar(name, p, flag);
+               } while ((name = *++aptr) != NULL);
+       } else {
+               showvars(argv[0], flag, 0);
        }
-       putc('"', tracefile);
+       return 0;
 }
 
 
-static void
-trargs(char **ap)
-{
-       if (tracefile == NULL)
-               return;
-       while (*ap) {
-               trstring(*ap++);
-               if (*ap)
-                       putc(' ', tracefile);
-               else
-                       putc('\n', tracefile);
-       }
-       fflush(tracefile);
-}
-
+/*
+ * Make a variable a local variable.  When a variable is made local, it's
+ * value and flags are saved in a localvar structure.  The saved values
+ * will be restored when the shell function returns.  We handle the name
+ * "-" as a special case.
+ */
 
-static void
-opentrace()
+static inline void
+mklocal(char *name)
 {
-       char s[100];
-#ifdef O_APPEND
-       int flags;
-#endif
+       struct localvar *lvp;
+       struct var **vpp;
+       struct var *vp;
 
-       if (!debug)
-               return;
-#ifdef not_this_way
-       {
+       INTOFF;
+       lvp = ckmalloc(sizeof (struct localvar));
+       if (name[0] == '-' && name[1] == '\0') {
                char *p;
-               if ((p = getenv("HOME")) == NULL) {
-                       if (geteuid() == 0)
-                               p = "/";
+               p = ckmalloc(sizeof(optlist));
+               lvp->text = memcpy(p, optlist, sizeof(optlist));
+               vp = NULL;
+       } else {
+               char *eq;
+
+               vpp = hashvar(name);
+               vp = *findvar(vpp, name);
+               eq = strchr(name, '=');
+               if (vp == NULL) {
+                       if (eq)
+                               setvareq(name, VSTRFIXED);
                        else
-                               p = "/tmp";
+                               setvar(name, NULL, VSTRFIXED);
+                       vp = *vpp;      /* the new variable */
+                       lvp->flags = VUNSET;
+               } else {
+                       lvp->text = vp->text;
+                       lvp->flags = vp->flags;
+                       vp->flags |= VSTRFIXED|VTEXTFIXED;
+                       if (eq)
+                               setvareq(name, 0);
                }
-               strcpy(s, p);
-               strcat(s, "/trace");
        }
-#else
-       strcpy(s, "./trace");
-#endif /* not_this_way */
-       if ((tracefile = wfopen(s, "a")) == NULL)
-               return;
-#ifdef O_APPEND
-       if ((flags = fcntl(fileno(tracefile), F_GETFL, 0)) >= 0)
-               fcntl(fileno(tracefile), F_SETFL, flags | O_APPEND);
-#endif
-       fputs("\nTracing started.\n", tracefile);
-       fflush(tracefile);
+       lvp->vp = vp;
+       lvp->next = localvars;
+       localvars = lvp;
+       INTON;
 }
-#endif /* DEBUG */
-
 
 /*
- * The trap builtin.
+ * The "local" command.
  */
 
 static int
-trapcmd(int argc, char **argv)
+localcmd(int argc, char **argv)
 {
-       char *action;
-       char **ap;
-       int signo;
-
-       if (argc <= 1) {
-               for (signo = 0 ; signo < NSIG ; signo++) {
-                       if (trap[signo] != NULL) {
-                               char *p;
-                               const char *sn;
+       char *name;
 
-                               p = single_quote(trap[signo]);
-                               sn = sys_siglist[signo];
-                               if(sn==NULL)
-                                       sn = u_signal_names(0, &signo, 0);
-                               if(sn==NULL)
-                                       sn = "???";
-                               printf("trap -- %s %s\n", p, sn);
-                               stunalloc(p);
-                       }
-               }
-               return 0;
-       }
-       ap = argv + 1;
-       if (argc == 2)
-               action = NULL;
-       else
-               action = *ap++;
-       while (*ap) {
-               if ((signo = decode_signal(*ap, 0)) < 0)
-                       error("%s: bad trap", *ap);
-               INTOFF;
-               if (action) {
-                       if (action[0] == '-' && action[1] == '\0')
-                               action = NULL;
-                       else
-                               action = xstrdup(action);
-               }
-               if (trap[signo])
-                       ckfree(trap[signo]);
-               trap[signo] = action;
-               if (signo != 0)
-                       setsignal(signo);
-               INTON;
-               ap++;
+       argv = argptr;
+       while ((name = *argv++) != NULL) {
+               mklocal(name);
        }
        return 0;
 }
 
 
-
-
-
-
 /*
- * Set the signal handler for the specified signal.  The routine figures
- * out what it should be set to.
+ * Called after a function returns.
+ * Interrupts must be off.
  */
 
 static void
-setsignal(int signo)
+poplocalvars(void)
 {
-       int action;
-       char *t;
-       struct sigaction act;
-
-       if ((t = trap[signo]) == NULL)
-               action = S_DFL;
-       else if (*t != '\0')
-               action = S_CATCH;
-       else
-               action = S_IGN;
-       if (rootshell && action == S_DFL) {
-               switch (signo) {
-               case SIGINT:
-                       if (iflag || minusc || sflag == 0)
-                               action = S_CATCH;
-                       break;
-               case SIGQUIT:
-#ifdef DEBUG
-                       {
-
-                       if (debug)
-                               break;
-                       }
-#endif
-                       /* FALLTHROUGH */
-               case SIGTERM:
-                       if (iflag)
-                               action = S_IGN;
-                       break;
-#ifdef CONFIG_ASH_JOB_CONTROL
-               case SIGTSTP:
-               case SIGTTOU:
-                       if (mflag)
-                               action = S_IGN;
-                       break;
-#endif
-               }
-       }
+       struct localvar *lvp;
+       struct var *vp;
 
-       t = &sigmode[signo - 1];
-       if (*t == 0) {
-               /*
-                * current setting unknown
-                */
-               if (sigaction(signo, 0, &act) == -1) {
-                       /*
-                        * Pretend it worked; maybe we should give a warning
-                        * here, but other shells don't. We don't alter
-                        * sigmode, so that we retry every time.
-                        */
-                       return;
-               }
-               if (act.sa_handler == SIG_IGN) {
-                       if (mflag && (signo == SIGTSTP ||
-                            signo == SIGTTIN || signo == SIGTTOU)) {
-                               *t = S_IGN;     /* don't hard ignore these */
-                       } else
-                               *t = S_HARD_IGN;
+       while ((lvp = localvars) != NULL) {
+               localvars = lvp->next;
+               vp = lvp->vp;
+               TRACE(("poplocalvar %s", vp ? vp->text : "-"));
+               if (vp == NULL) {       /* $- saved */
+                       memcpy(optlist, lvp->text, sizeof(optlist));
+                       ckfree(lvp->text);
+                       optschanged();
+               } else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) {
+                       unsetvar(vp->text);
                } else {
-                       *t = S_RESET;   /* force to be set */
+                       if (vp->func)
+                               (*vp->func)(strchrnul(lvp->text, '=') + 1);
+                       if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
+                               ckfree(vp->text);
+                       vp->flags = lvp->flags;
+                       vp->text = lvp->text;
                }
+               ckfree(lvp);
        }
-       if (*t == S_HARD_IGN || *t == action)
-               return;
-       act.sa_handler = ((action == S_CATCH) ? onsig
-                                         : ((action == S_IGN) ? SIG_IGN : SIG_DFL));
-       *t = action;
-       act.sa_flags = 0;
-       sigemptyset(&act.sa_mask);
-       sigaction(signo, &act, 0);
 }
 
+
 /*
- * Ignore a signal.
+ * The unset builtin command.  We unset the function before we unset the
+ * variable to allow a function to be unset when there is a readonly variable
+ * with the same name.
  */
 
-static void
-ignoresig(int signo)
+int
+unsetcmd(int argc, char **argv)
 {
-       if (sigmode[signo - 1] != S_IGN && sigmode[signo - 1] != S_HARD_IGN) {
-               signal(signo, SIG_IGN);
+       char **ap;
+       int i;
+       int flag = 0;
+       int ret = 0;
+
+       while ((i = nextopt("vf")) != '\0') {
+               flag = i;
        }
-       sigmode[signo - 1] = S_HARD_IGN;
+
+       for (ap = argptr; *ap ; ap++) {
+               if (flag != 'f') {
+                       i = unsetvar(*ap);
+                       ret |= i;
+                       if (!(i & 2))
+                               continue;
+               }
+               if (flag != 'v')
+                       unsetfunc(*ap);
+       }
+       return ret & 1;
 }
 
 
 /*
- * Signal handler.
+ * Unset the specified variable.
  */
 
-static void
-onsig(int signo)
+int
+unsetvar(const char *s)
 {
-       if (signo == SIGINT && trap[SIGINT] == NULL) {
-               onint();
-               return;
+       struct var **vpp;
+       struct var *vp;
+       int retval;
+
+       vpp = findvar(hashvar(s), s);
+       vp = *vpp;
+       retval = 2;
+       if (vp) {
+               int flags = vp->flags;
+
+               retval = 1;
+               if (flags & VREADONLY)
+                       goto out;
+#ifdef DYNAMIC_VAR
+               vp->flags &= ~VDYNAMIC;
+#endif
+               if (flags & VUNSET)
+                       goto ok;
+               if ((flags & VSTRFIXED) == 0) {
+                       INTOFF;
+                       if ((flags & (VTEXTFIXED|VSTACK)) == 0)
+                               ckfree(vp->text);
+                       *vpp = vp->next;
+                       ckfree(vp);
+                       INTON;
+               } else {
+                       setvar(s, 0, 0);
+                       vp->flags &= ~VEXPORT;
+               }
+ok:
+               retval = 0;
        }
-       gotsig[signo - 1] = 1;
-       pendingsigs++;
+
+out:
+       return retval;
 }
 
 
+
 /*
- * Called to execute a trap.  Perhaps we should avoid entering new trap
- * handlers while we are executing a trap handler.
+ * Find the appropriate entry in the hash table from the name.
  */
 
-static void
-dotrap(void)
+static struct var **
+hashvar(const char *p)
 {
-       int i;
-       int savestatus;
+       unsigned int hashval;
 
-       for (;;) {
-               for (i = 1 ; ; i++) {
-                       if (gotsig[i - 1])
-                               break;
-                       if (i >= NSIG - 1)
-                               goto done;
-               }
-               gotsig[i - 1] = 0;
-               savestatus=exitstatus;
-               evalstring(trap[i], 0);
-               exitstatus=savestatus;
-       }
-done:
-       pendingsigs = 0;
+       hashval = ((unsigned char) *p) << 4;
+       while (*p && *p != '=')
+               hashval += (unsigned char) *p++;
+       return &vartab[hashval % VTABSIZE];
 }
 
+
+
 /*
- * Called to exit the shell.
+ * Compares two strings up to the first = or '\0'.  The first
+ * string must be terminated by '='; the second may be terminated by
+ * either '=' or '\0'.
  */
 
-static void
-exitshell(int status)
+int
+varcmp(const char *p, const char *q)
 {
-       struct jmploc loc1, loc2;
-       char *p;
+       int c, d;
 
-       TRACE(("exitshell(%d) pid=%d\n", status, getpid()));
-       if (setjmp(loc1.loc)) {
-               goto l1;
+       while ((c = *p) == (d = *q)) {
+               if (!c || c == '=')
+                       goto out;
+               p++;
+               q++;
        }
-       if (setjmp(loc2.loc)) {
-               goto l2;
+       if (c == '=')
+               c = 0;
+       if (d == '=')
+               d = 0;
+out:
+       return c - d;
+}
+
+static int
+vpcmp(const void *a, const void *b)
+{
+       return varcmp(*(const char **)a, *(const char **)b);
+}
+
+static struct var **
+findvar(struct var **vpp, const char *name)
+{
+       for (; *vpp; vpp = &(*vpp)->next) {
+               if (varequal((*vpp)->text, name)) {
+                       break;
+               }
        }
-       handler = &loc1;
-       if ((p = trap[0]) != NULL && *p != '\0') {
-               trap[0] = NULL;
-               evalstring(p, 0);
+       return vpp;
+}
+/*      setmode.c      */
+
+#include <sys/times.h>
+
+static const unsigned char timescmd_str[] = {
+       ' ',  offsetof(struct tms, tms_utime),
+       '\n', offsetof(struct tms, tms_stime),
+       ' ',  offsetof(struct tms, tms_cutime),
+       '\n', offsetof(struct tms, tms_cstime),
+       0
+};
+
+static int timescmd(int ac, char **av)
+{
+       long int clk_tck, s, t;
+       const unsigned char *p;
+       struct tms buf;
+
+       clk_tck = sysconf(_SC_CLK_TCK);
+       times(&buf);
+
+       p = timescmd_str;
+       do {
+               t = *(clock_t *)(((char *) &buf) + p[1]);
+               s = t / clk_tck;
+               out1fmt("%ldm%ld.%.3lds%c",
+                       s/60, s%60,
+                       ((t - s * clk_tck) * 1000) / clk_tck,
+                       p[0]);
+       } while (*(p += 2));
+
+       return 0;
+}
+
+#ifdef CONFIG_ASH_MATH_SUPPORT
+static arith_t
+dash_arith(const char *s)
+{
+       arith_t result;
+       int errcode = 0;
+
+       INTOFF;
+       result = arith(s, &errcode);
+       if (errcode < 0) {
+               if (errcode == -3)
+                       sh_error("exponent less than 0");
+               else if (errcode == -2)
+                       sh_error("divide by zero");
+               else if (errcode == -5)
+                       sh_error("expression recursion loop detected");
+               else
+                       synerror(s);
        }
-l1:   handler = &loc2;                  /* probably unnecessary */
-       flushall();
-#ifdef CONFIG_ASH_JOB_CONTROL
-       setjobctl(0);
-#endif
-l2:   _exit(status);
-       /* NOTREACHED */
+       INTON;
+
+       return (result);
 }
 
-static int decode_signal(const char *string, int minsig)
+
+/*
+ *  The let builtin. partial stolen from GNU Bash, the Bourne Again SHell.
+ *  Copyright (C) 1987, 1989, 1991 Free Software Foundation, Inc.
+ *
+ *  Copyright (C) 2003 Vladimir Oleynik <dzo@simtreas.ru>
+ */
+
+static int
+letcmd(int argc, char **argv)
 {
-       int signo;
-       const char *name = u_signal_names(string, &signo, minsig);
+       char **ap;
+       arith_t i;
+
+       ap = argv + 1;
+       if(!*ap)
+               sh_error("expression expected");
+       for (ap = argv + 1; *ap; ap++) {
+               i = dash_arith(*ap);
+       }
 
-       return name ? signo : -1;
+       return (!i);
 }
+#endif /* CONFIG_ASH_MATH_SUPPORT */
 
-static struct var **hashvar (const char *);
-static void showvars (const char *, int, int);
-static struct var **findvar (struct var **, const char *);
+/*      miscbltin.c  */
 
 /*
- * Initialize the varable symbol tables and import the environment
+ * Miscellaneous builtins.
  */
 
+#undef rflag
+
+#ifdef __GLIBC__
+#if __GLIBC__ == 2 && __GLIBC_MINOR__ < 1
+typedef enum __rlimit_resource rlim_t;
+#endif
+#endif
+
+
 /*
- * This routine initializes the builtin variables.  It is called when the
- * shell is initialized and again when a shell procedure is spawned.
+ * The read builtin.  The -e option causes backslashes to escape the
+ * following character.
+ *
+ * This uses unbuffered input, which may be avoidable in some cases.
  */
 
-static void
-initvar() {
-       const struct varinit *ip;
-       struct var *vp;
-       struct var **vpp;
+static int
+readcmd(int argc, char **argv)
+{
+       char **ap;
+       int backslash;
+       char c;
+       int rflag;
+       char *prompt;
+       const char *ifs;
+       char *p;
+       int startword;
+       int status;
+       int i;
+#if defined(CONFIG_ASH_READ_NCHARS)
+       int nch_flag = 0;
+       int nchars = 0;
+       int silent = 0;
+       struct termios tty, old_tty;
+#endif
+#if defined(CONFIG_ASH_READ_TIMEOUT)
+       fd_set set;
+       struct timeval ts;
+
+       ts.tv_sec = ts.tv_usec = 0;
+#endif
+
+       rflag = 0;
+       prompt = NULL;
+#if defined(CONFIG_ASH_READ_NCHARS) && defined(CONFIG_ASH_READ_TIMEOUT)
+       while ((i = nextopt("p:rt:n:s")) != '\0')
+#elif defined(CONFIG_ASH_READ_NCHARS)
+       while ((i = nextopt("p:rn:s")) != '\0')
+#elif defined(CONFIG_ASH_READ_TIMEOUT)
+       while ((i = nextopt("p:rt:")) != '\0')
+#else
+       while ((i = nextopt("p:r")) != '\0')
+#endif
+       {
+               switch(i) {
+               case 'p':
+                       prompt = optionarg;
+                       break;
+#if defined(CONFIG_ASH_READ_NCHARS)
+               case 'n':
+                       nchars = strtol(optionarg, &p, 10);
+                       if (*p)
+                               sh_error("invalid count");
+                       nch_flag = (nchars > 0);
+                       break;
+               case 's':
+                       silent = 1;
+                       break;
+#endif
+#if defined(CONFIG_ASH_READ_TIMEOUT)
+               case 't':
+                       ts.tv_sec = strtol(optionarg, &p, 10);
+                       ts.tv_usec = 0;
+                       if (*p == '.') {
+                               char *p2;
+                               if (*++p) {
+                                       int scale;
+                                       ts.tv_usec = strtol(p, &p2, 10);
+                                       if (*p2)
+                                               sh_error("invalid timeout");
+                                       scale = p2 - p;
+                                       /* normalize to usec */
+                                       if (scale > 6)
+                                               sh_error("invalid timeout");
+                                       while (scale++ < 6)
+                                               ts.tv_usec *= 10;
+                               }
+                       } else if (*p) {
+                               sh_error("invalid timeout");
+                       }
+                       if ( ! ts.tv_sec && ! ts.tv_usec)
+                               sh_error("invalid timeout");
+                       break;
+#endif
+               case 'r':
+                       rflag = 1;
+                       break;
+               default:
+                       break;
+               }
+       }
+       if (prompt && isatty(0)) {
+               out2str(prompt);
+       }
+       if (*(ap = argptr) == NULL)
+               sh_error("arg count");
+       if ((ifs = bltinlookup("IFS")) == NULL)
+               ifs = defifs;
+#if defined(CONFIG_ASH_READ_NCHARS)
+       if (nch_flag || silent) {
+               tcgetattr(0, &tty);
+               old_tty = tty;
+               if (nch_flag) {
+                   tty.c_lflag &= ~ICANON;
+                   tty.c_cc[VMIN] = nchars;
+               }
+               if (silent) {
+                   tty.c_lflag &= ~(ECHO|ECHOK|ECHONL);
 
-       for (ip = varinit ; (vp = ip->var) != NULL ; ip++) {
-               if ((vp->flags & VEXPORT) == 0) {
-                       vpp = hashvar(ip->text);
-                       vp->next = *vpp;
-                       *vpp = vp;
-                       vp->text = xstrdup(ip->text);
-                       vp->flags = ip->flags;
-                       vp->func = ip->func;
                }
+               tcsetattr(0, TCSANOW, &tty);
        }
-#if !defined(CONFIG_FEATURE_COMMAND_EDITING) || !defined(CONFIG_FEATURE_SH_FANCY_PROMPT)
-       /*
-        * PS1 depends on uid
-        */
-       if ((vps1.flags & VEXPORT) == 0) {
-               vpp = hashvar("PS1=$");
-               vps1.next = *vpp;
-               *vpp = &vps1;
-               vps1.text = xstrdup(geteuid() ? "PS1=$ " : "PS1=# ");
-               vps1.flags = VSTRFIXED|VTEXTFIXED;
+#endif
+#if defined(CONFIG_ASH_READ_TIMEOUT)
+       if (ts.tv_sec || ts.tv_usec) {
+               FD_ZERO (&set);
+               FD_SET (0, &set);
+
+               i = select (FD_SETSIZE, &set, NULL, NULL, &ts);
+               if (!i) {
+#if defined(CONFIG_ASH_READ_NCHARS)
+                       if (nch_flag)
+                               tcsetattr(0, TCSANOW, &old_tty);
+#endif
+                       return 1;
+               }
+       }
+#endif
+       status = 0;
+       startword = 1;
+       backslash = 0;
+       STARTSTACKSTR(p);
+#if defined(CONFIG_ASH_READ_NCHARS)
+       while (!nch_flag || nchars--)
+#else
+       for (;;)
+#endif
+       {
+               if (read(0, &c, 1) != 1) {
+                       status = 1;
+                       break;
+               }
+               if (c == '\0')
+                       continue;
+               if (backslash) {
+                       backslash = 0;
+                       if (c != '\n')
+                               goto put;
+                       continue;
+               }
+               if (!rflag && c == '\\') {
+                       backslash++;
+                       continue;
+               }
+               if (c == '\n')
+                       break;
+               if (startword && *ifs == ' ' && strchr(ifs, c)) {
+                       continue;
+               }
+               startword = 0;
+               if (ap[1] != NULL && strchr(ifs, c) != NULL) {
+                       STACKSTRNUL(p);
+                       setvar(*ap, stackblock(), 0);
+                       ap++;
+                       startword = 1;
+                       STARTSTACKSTR(p);
+               } else {
+put:
+                       STPUTC(c, p);
+               }
        }
+#if defined(CONFIG_ASH_READ_NCHARS)
+       if (nch_flag || silent)
+               tcsetattr(0, TCSANOW, &old_tty);
 #endif
+
+       STACKSTRNUL(p);
+       /* Remove trailing blanks */
+       while ((char *)stackblock() <= --p && strchr(ifs, *p) != NULL)
+               *p = '\0';
+       setvar(*ap, stackblock(), 0);
+       while (*++ap != NULL)
+               setvar(*ap, nullstr, 0);
+       return status;
 }
 
-/*
- * Set the value of a variable.  The flags argument is ored with the
- * flags of the variable.  If val is NULL, the variable is unset.
- */
 
-static void
-setvar(const char *name, const char *val, int flags)
+static int umaskcmd(int argc, char **argv)
 {
-       const char *p;
-       int len;
-       int namelen;
-       char *nameeq;
-       int isbad;
-       int vallen = 0;
+       static const char permuser[3] = "ugo";
+       static const char permmode[3] = "rwx";
+       static const short int permmask[] = {
+               S_IRUSR, S_IWUSR, S_IXUSR,
+               S_IRGRP, S_IWGRP, S_IXGRP,
+               S_IROTH, S_IWOTH, S_IXOTH
+       };
 
-       isbad = 0;
-       p = name;
-       if (! is_name(*p))
-               isbad = 1;
-       p++;
-       for (;;) {
-               if (! is_in_name(*p)) {
-                       if (*p == '\0' || *p == '=')
-                               break;
-                       isbad = 1;
-               }
-               p++;
-       }
-       namelen = p - name;
-       if (isbad)
-               error("%.*s: bad variable name", namelen, name);
-       len = namelen + 2;              /* 2 is space for '=' and '\0' */
-       if (val == NULL) {
-               flags |= VUNSET;
-       } else {
-               len += vallen = strlen(val);
+       char *ap;
+       mode_t mask;
+       int i;
+       int symbolic_mode = 0;
+
+       while (nextopt("S") != '\0') {
+               symbolic_mode = 1;
        }
+
        INTOFF;
-       nameeq = xmalloc(len);
-       memcpy(nameeq, name, namelen);
-       nameeq[namelen] = '=';
-       if (val) {
-               memcpy(nameeq + namelen + 1, val, vallen + 1);
-       } else {
-               nameeq[namelen + 1] = '\0';
-       }
-       setvareq(nameeq, flags);
+       mask = umask(0);
+       umask(mask);
        INTON;
-}
 
+       if ((ap = *argptr) == NULL) {
+               if (symbolic_mode) {
+                       char buf[18];
+                       char *p = buf;
+
+                       for (i = 0; i < 3; i++) {
+                               int j;
 
+                               *p++ = permuser[i];
+                               *p++ = '=';
+                               for (j = 0; j < 3; j++) {
+                                       if ((mask & permmask[3 * i + j]) == 0) {
+                                               *p++ = permmode[j];
+                                       }
+                               }
+                               *p++ = ',';
+                       }
+                       *--p = 0;
+                       puts(buf);
+               } else {
+                       out1fmt("%.4o\n", mask);
+               }
+       } else {
+               if (is_digit((unsigned char) *ap)) {
+                       mask = 0;
+                       do {
+                               if (*ap >= '8' || *ap < '0')
+                                       sh_error(illnum, argv[1]);
+                               mask = (mask << 3) + (*ap - '0');
+                       } while (*++ap != '\0');
+                       umask(mask);
+               } else {
+                       mask = ~mask & 0777;
+                       if (!bb_parse_mode(ap, &mask)) {
+                               sh_error("Illegal mode: %s", ap);
+                       }
+                       umask(~mask & 0777);
+               }
+       }
+       return 0;
+}
 
 /*
- * Same as setvar except that the variable and value are passed in
- * the first argument as name=value.  Since the first argument will
- * be actually stored in the table, it should not be a string that
- * will go away.
+ * ulimit builtin
+ *
+ * This code, originally by Doug Gwyn, Doug Kingston, Eric Gisin, and
+ * Michael Rendell was ripped from pdksh 5.0.8 and hacked for use with
+ * ash by J.T. Conklin.
+ *
+ * Public domain.
  */
 
-static void
-setvareq(char *s, int flags)
-{
-       struct var *vp, **vpp;
+struct limits {
+       const char *name;
+       int     cmd;
+       int     factor; /* multiply by to get rlim_{cur,max} values */
+       char    option;
+};
 
-       vpp = hashvar(s);
-       flags |= (VEXPORT & (((unsigned) (1 - aflag)) - 1));
-       if ((vp = *findvar(vpp, s))) {
-               if (vp->flags & VREADONLY) {
-                       size_t len = strchr(s, '=') - s;
-                       error("%.*s: is read only", len, s);
-               }
-               INTOFF;
+static const struct limits limits[] = {
+#ifdef RLIMIT_CPU
+       { "time(seconds)",              RLIMIT_CPU,        1, 't' },
+#endif
+#ifdef RLIMIT_FSIZE
+       { "file(blocks)",               RLIMIT_FSIZE,    512, 'f' },
+#endif
+#ifdef RLIMIT_DATA
+       { "data(kbytes)",               RLIMIT_DATA,    1024, 'd' },
+#endif
+#ifdef RLIMIT_STACK
+       { "stack(kbytes)",              RLIMIT_STACK,   1024, 's' },
+#endif
+#ifdef  RLIMIT_CORE
+       { "coredump(blocks)",           RLIMIT_CORE,     512, 'c' },
+#endif
+#ifdef RLIMIT_RSS
+       { "memory(kbytes)",             RLIMIT_RSS,     1024, 'm' },
+#endif
+#ifdef RLIMIT_MEMLOCK
+       { "locked memory(kbytes)",      RLIMIT_MEMLOCK, 1024, 'l' },
+#endif
+#ifdef RLIMIT_NPROC
+       { "process",                    RLIMIT_NPROC,      1, 'p' },
+#endif
+#ifdef RLIMIT_NOFILE
+       { "nofiles",                    RLIMIT_NOFILE,     1, 'n' },
+#endif
+#ifdef RLIMIT_AS
+       { "vmemory(kbytes)",            RLIMIT_AS,      1024, 'v' },
+#endif
+#ifdef RLIMIT_LOCKS
+       { "locks",                      RLIMIT_LOCKS,      1, 'w' },
+#endif
+       { (char *) 0,                   0,                 0,  '\0' }
+};
 
-               if (vp->func && (flags & VNOFUNC) == 0)
-                       (*vp->func)(strchr(s, '=') + 1);
+enum limtype { SOFT = 0x1, HARD = 0x2 };
 
-               if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
-                       ckfree(vp->text);
+static void printlim(enum limtype how, const struct rlimit *limit,
+                       const struct limits *l)
+{
+       rlim_t val;
 
-               vp->flags &= ~(VTEXTFIXED|VSTACK|VUNSET);
-               vp->flags |= flags;
-               vp->text = s;
+       val = limit->rlim_max;
+       if (how & SOFT)
+               val = limit->rlim_cur;
 
-#ifdef CONFIG_ASH_MAIL
-               /*
-                * We could roll this to a function, to handle it as
-                * a regular variable function callback, but why bother?
-                */
-               if (iflag && (vp == &vmpath || (vp == &vmail && !mpathset())))
-                       chkmail(1);
-#endif
-               INTON;
-               return;
+       if (val == RLIM_INFINITY)
+               out1fmt("unlimited\n");
+       else {
+               val /= l->factor;
+               out1fmt("%lld\n", (long long) val);
        }
-       /* not found */
-       vp = xmalloc(sizeof (*vp));
-       vp->flags = flags;
-       vp->text = s;
-       vp->next = *vpp;
-       vp->func = NULL;
-       *vpp = vp;
 }
 
-
-
-/*
- * Process a linked list of variable assignments.
- */
-
-static void
-listsetvar(struct strlist *mylist)
+int
+ulimitcmd(int argc, char **argv)
 {
-       struct strlist *lp;
+       int     c;
+       rlim_t val = 0;
+       enum limtype how = SOFT | HARD;
+       const struct limits     *l;
+       int             set, all = 0;
+       int             optc, what;
+       struct rlimit   limit;
 
-       INTOFF;
-       for (lp = mylist ; lp ; lp = lp->next) {
-               setvareq(xstrdup(lp->text), 0);
-       }
-       INTON;
-}
+       what = 'f';
+       while ((optc = nextopt("HSa"
+#ifdef RLIMIT_CPU
+                               "t"
+#endif
+#ifdef RLIMIT_FSIZE
+                               "f"
+#endif
+#ifdef RLIMIT_DATA
+                               "d"
+#endif
+#ifdef RLIMIT_STACK
+                               "s"
+#endif
+#ifdef RLIMIT_CORE
+                               "c"
+#endif
+#ifdef RLIMIT_RSS
+                               "m"
+#endif
+#ifdef RLIMIT_MEMLOCK
+                               "l"
+#endif
+#ifdef RLIMIT_NPROC
+                               "p"
+#endif
+#ifdef RLIMIT_NOFILE
+                               "n"
+#endif
+#ifdef RLIMIT_AS
+                               "v"
+#endif
+#ifdef RLIMIT_LOCKS
+                               "w"
+#endif
+                                               )) != '\0')
+               switch (optc) {
+               case 'H':
+                       how = HARD;
+                       break;
+               case 'S':
+                       how = SOFT;
+                       break;
+               case 'a':
+                       all = 1;
+                       break;
+               default:
+                       what = optc;
+               }
 
+       for (l = limits; l->option != what; l++)
+               ;
 
+       set = *argptr ? 1 : 0;
+       if (set) {
+               char *p = *argptr;
 
-/*
- * Find the value of a variable.  Returns NULL if not set.
- */
+               if (all || argptr[1])
+                       sh_error("too many arguments");
+               if (strncmp(p, "unlimited\n", 9) == 0)
+                       val = RLIM_INFINITY;
+               else {
+                       val = (rlim_t) 0;
 
-static const char *
-lookupvar(const char *name)
-{
-       struct var *v;
+                       while ((c = *p++) >= '0' && c <= '9')
+                       {
+                               val = (val * 10) + (long)(c - '0');
+                               if (val < (rlim_t) 0)
+                                       break;
+                       }
+                       if (c)
+                               sh_error("bad number");
+                       val *= l->factor;
+               }
+       }
+       if (all) {
+               for (l = limits; l->name; l++) {
+                       getrlimit(l->cmd, &limit);
+                       out1fmt("%-20s ", l->name);
+                       printlim(how, &limit, l);
+               }
+               return 0;
+       }
 
-       if ((v = *findvar(hashvar(name), name)) && !(v->flags & VUNSET)) {
-               return strchr(v->text, '=') + 1;
+       getrlimit(l->cmd, &limit);
+       if (set) {
+               if (how & HARD)
+                       limit.rlim_max = val;
+               if (how & SOFT)
+                       limit.rlim_cur = val;
+               if (setrlimit(l->cmd, &limit) < 0)
+                       sh_error("error setting limit (%m)");
+       } else {
+               printlim(how, &limit, l);
        }
-       return NULL;
+       return 0;
 }
 
 
+#ifdef CONFIG_ASH_MATH_SUPPORT
 
-/*
- * Search the environment of a builtin command.
- */
-
-static const char *
-bltinlookup(const char *name)
-{
-       const struct strlist *sp;
+/* Copyright (c) 2001 Aaron Lehmann <aaronl@vitelus.com>
+
+   Permission is hereby granted, free of charge, to any person obtaining
+   a copy of this software and associated documentation files (the
+   "Software"), to deal in the Software without restriction, including
+   without limitation the rights to use, copy, modify, merge, publish,
+   distribute, sublicense, and/or sell copies of the Software, and to
+   permit persons to whom the Software is furnished to do so, subject to
+   the following conditions:
+
+   The above copyright notice and this permission notice shall be
+   included in all copies or substantial portions of the Software.
+
+   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+   IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+   CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+   TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+   SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
 
-       for (sp = cmdenviron ; sp ; sp = sp->next) {
-               if (varequal(sp->text, name))
-                       return strchr(sp->text, '=') + 1;
-       }
-       return lookupvar(name);
-}
+/* This is my infix parser/evaluator. It is optimized for size, intended
+ * as a replacement for yacc-based parsers. However, it may well be faster
+ * than a comparable parser written in yacc. The supported operators are
+ * listed in #defines below. Parens, order of operations, and error handling
+ * are supported. This code is thread safe. The exact expression format should
+ * be that which POSIX specifies for shells. */
 
+/* The code uses a simple two-stack algorithm. See
+ * http://www.onthenet.com.au/~grahamis/int2008/week02/lect02.html
+ * for a detailed explanation of the infix-to-postfix algorithm on which
+ * this is based (this code differs in that it applies operators immediately
+ * to the stack instead of adding them to a queue to end up with an
+ * expression). */
 
+/* To use the routine, call it with an expression string and error return
+ * pointer */
 
 /*
- * Generate a list of exported variables.  This routine is used to construct
- * the third argument to execve when executing a program.
+ * Aug 24, 2001              Manuel Novoa III
+ *
+ * Reduced the generated code size by about 30% (i386) and fixed several bugs.
+ *
+ * 1) In arith_apply():
+ *    a) Cached values of *numptr and &(numptr[-1]).
+ *    b) Removed redundant test for zero denominator.
+ *
+ * 2) In arith():
+ *    a) Eliminated redundant code for processing operator tokens by moving
+ *       to a table-based implementation.  Also folded handling of parens
+ *       into the table.
+ *    b) Combined all 3 loops which called arith_apply to reduce generated
+ *       code size at the cost of speed.
+ *
+ * 3) The following expressions were treated as valid by the original code:
+ *       1()  ,    0!  ,    1 ( *3 )   .
+ *    These bugs have been fixed by internally enclosing the expression in
+ *    parens and then checking that all binary ops and right parens are
+ *    preceded by a valid expression (NUM_TOKEN).
+ *
+ * Note: It may be desirable to replace Aaron's test for whitespace with
+ * ctype's isspace() if it is used by another busybox applet or if additional
+ * whitespace chars should be considered.  Look below the "#include"s for a
+ * precompiler test.
  */
 
-static char **
-environment() {
-       int nenv;
-       struct var **vpp;
-       struct var *vp;
-       char **env;
-       char **ep;
-
-       nenv = 0;
-       for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
-               for (vp = *vpp ; vp ; vp = vp->next)
-                       if (vp->flags & VEXPORT)
-                               nenv++;
-       }
-       ep = env = stalloc((nenv + 1) * sizeof *env);
-       for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
-               for (vp = *vpp ; vp ; vp = vp->next)
-                       if (vp->flags & VEXPORT)
-                               *ep++ = vp->text;
-       }
-       *ep = NULL;
-       return env;
-}
-
+/*
+ * Aug 26, 2001              Manuel Novoa III
+ *
+ * Return 0 for null expressions.  Pointed out by Vladimir Oleynik.
+ *
+ * Merge in Aaron's comments previously posted to the busybox list,
+ * modified slightly to take account of my changes to the code.
+ *
+ */
 
 /*
- * Called when a shell procedure is invoked to clear out nonexported
- * variables.  It is also necessary to reallocate variables of with
- * VSTACK set since these are currently allocated on the stack.
+ *  (C) 2003 Vladimir Oleynik <dzo@simtreas.ru>
+ *
+ * - allow access to variable,
+ *   used recursive find value indirection (c=2*2; a="c"; $((a+=2)) produce 6)
+ * - realize assign syntax (VAR=expr, +=, *= etc)
+ * - realize exponentiation (** operator)
+ * - realize comma separated - expr, expr
+ * - realise ++expr --expr expr++ expr--
+ * - realise expr ? expr : expr (but, second expr calculate always)
+ * - allow hexadecimal and octal numbers
+ * - was restored loses XOR operator
+ * - remove one goto label, added three ;-)
+ * - protect $((num num)) as true zero expr (Manuel`s error)
+ * - always use special isspace(), see comment from bash ;-)
  */
 
-static void
-shprocvar(void) {
-       struct var **vpp;
-       struct var *vp, **prev;
-
-       for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
-               for (prev = vpp ; (vp = *prev) != NULL ; ) {
-                       if ((vp->flags & VEXPORT) == 0) {
-                               *prev = vp->next;
-                               if ((vp->flags & VTEXTFIXED) == 0)
-                                       ckfree(vp->text);
-                               if ((vp->flags & VSTRFIXED) == 0)
-                                       ckfree(vp);
-                       } else {
-                               if (vp->flags & VSTACK) {
-                                       vp->text = xstrdup(vp->text);
-                                       vp->flags &=~ VSTACK;
-                               }
-                               prev = &vp->next;
-                       }
-               }
-       }
-       initvar();
-}
 
+#define arith_isspace(arithval) \
+       (arithval == ' ' || arithval == '\n' || arithval == '\t')
 
 
-/*
- * Command to list all variables which are set.  Currently this command
- * is invoked from the set command when the set command is called without
- * any variables.
- */
+typedef unsigned char operator;
 
-static int
-showvarscmd(int argc, char **argv)
-{
-       showvars(nullstr, VUNSET, VUNSET);
-       return 0;
-}
+/* An operator's token id is a bit of a bitfield. The lower 5 bits are the
+ * precedence, and 3 high bits are an ID unique across operators of that
+ * precedence. The ID portion is so that multiple operators can have the
+ * same precedence, ensuring that the leftmost one is evaluated first.
+ * Consider * and /. */
 
+#define tok_decl(prec,id) (((id)<<5)|(prec))
+#define PREC(op) ((op) & 0x1F)
 
+#define TOK_LPAREN tok_decl(0,0)
 
-/*
- * The export and readonly commands.
- */
+#define TOK_COMMA tok_decl(1,0)
 
-static int
-exportcmd(int argc, char **argv)
-{
-       struct var *vp;
-       char *name;
-       const char *p;
-       int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT;
-       int pflag;
+#define TOK_ASSIGN tok_decl(2,0)
+#define TOK_AND_ASSIGN tok_decl(2,1)
+#define TOK_OR_ASSIGN tok_decl(2,2)
+#define TOK_XOR_ASSIGN tok_decl(2,3)
+#define TOK_PLUS_ASSIGN tok_decl(2,4)
+#define TOK_MINUS_ASSIGN tok_decl(2,5)
+#define TOK_LSHIFT_ASSIGN tok_decl(2,6)
+#define TOK_RSHIFT_ASSIGN tok_decl(2,7)
 
-       listsetvar(cmdenviron);
-       pflag = (nextopt("p") == 'p');
-       if (argc > 1 && !pflag) {
-               while ((name = *argptr++) != NULL) {
-                       if ((p = strchr(name, '=')) != NULL) {
-                               p++;
-                       } else {
-                               if ((vp = *findvar(hashvar(name), name))) {
-                                       vp->flags |= flag;
-                                       goto found;
-                               }
-                       }
-                       setvar(name, p, flag);
-found:;
-               }
-       } else {
-               showvars(argv[0], flag, 0);
-       }
-       return 0;
-}
+#define TOK_MUL_ASSIGN tok_decl(3,0)
+#define TOK_DIV_ASSIGN tok_decl(3,1)
+#define TOK_REM_ASSIGN tok_decl(3,2)
 
+/* all assign is right associativity and precedence eq, but (7+3)<<5 > 256 */
+#define convert_prec_is_assing(prec) do { if(prec == 3) prec = 2; } while(0)
 
-/*
- * The "local" command.
- */
+/* conditional is right associativity too */
+#define TOK_CONDITIONAL tok_decl(4,0)
+#define TOK_CONDITIONAL_SEP tok_decl(4,1)
 
-/* funcnest nonzero if we are currently evaluating a function */
+#define TOK_OR tok_decl(5,0)
 
-static int
-localcmd(int argc, char **argv)
-{
-       char *name;
+#define TOK_AND tok_decl(6,0)
 
-       if (! funcnest)
-               error("Not in a function");
-       while ((name = *argptr++) != NULL) {
-               mklocal(name);
-       }
-       return 0;
-}
+#define TOK_BOR tok_decl(7,0)
 
+#define TOK_BXOR tok_decl(8,0)
 
-/*
- * Make a variable a local variable.  When a variable is made local, it's
- * value and flags are saved in a localvar structure.  The saved values
- * will be restored when the shell function returns.  We handle the name
- * "-" as a special case.
- */
+#define TOK_BAND tok_decl(9,0)
 
-static void
-mklocal(char *name)
-{
-       struct localvar *lvp;
-       struct var **vpp;
-       struct var *vp;
+#define TOK_EQ tok_decl(10,0)
+#define TOK_NE tok_decl(10,1)
 
-       INTOFF;
-       lvp = xmalloc(sizeof (struct localvar));
-       if (name[0] == '-' && name[1] == '\0') {
-               char *p;
-               p = xmalloc(sizeof optet_vals);
-               lvp->text = memcpy(p, optet_vals, sizeof optet_vals);
-               vp = NULL;
-       } else {
-               vpp = hashvar(name);
-               vp = *findvar(vpp, name);
-               if (vp == NULL) {
-                       if (strchr(name, '='))
-                               setvareq(xstrdup(name), VSTRFIXED);
-                       else
-                               setvar(name, NULL, VSTRFIXED);
-                       vp = *vpp;      /* the new variable */
-                       lvp->text = NULL;
-                       lvp->flags = VUNSET;
-               } else {
-                       lvp->text = vp->text;
-                       lvp->flags = vp->flags;
-                       vp->flags |= VSTRFIXED|VTEXTFIXED;
-                       if (strchr(name, '='))
-                               setvareq(xstrdup(name), 0);
-               }
-       }
-       lvp->vp = vp;
-       lvp->next = localvars;
-       localvars = lvp;
-       INTON;
-}
+#define TOK_LT tok_decl(11,0)
+#define TOK_GT tok_decl(11,1)
+#define TOK_GE tok_decl(11,2)
+#define TOK_LE tok_decl(11,3)
 
+#define TOK_LSHIFT tok_decl(12,0)
+#define TOK_RSHIFT tok_decl(12,1)
 
-/*
- * Called after a function returns.
- */
+#define TOK_ADD tok_decl(13,0)
+#define TOK_SUB tok_decl(13,1)
 
-static void
-poplocalvars() {
-       struct localvar *lvp;
-       struct var *vp;
+#define TOK_MUL tok_decl(14,0)
+#define TOK_DIV tok_decl(14,1)
+#define TOK_REM tok_decl(14,2)
 
-       while ((lvp = localvars) != NULL) {
-               localvars = lvp->next;
-               vp = lvp->vp;
-               if (vp == NULL) {       /* $- saved */
-                       memcpy(optet_vals, lvp->text, sizeof optet_vals);
-                       ckfree(lvp->text);
-               } else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) {
-                       (void)unsetvar(vp->text);
-               } else {
-                       if ((vp->flags & VTEXTFIXED) == 0)
-                               ckfree(vp->text);
-                       vp->flags = lvp->flags;
-                       vp->text = lvp->text;
-               }
-               ckfree(lvp);
-       }
-}
+/* exponent is right associativity */
+#define TOK_EXPONENT tok_decl(15,1)
 
+/* For now unary operators. */
+#define UNARYPREC 16
+#define TOK_BNOT tok_decl(UNARYPREC,0)
+#define TOK_NOT tok_decl(UNARYPREC,1)
 
-static int
-setvarcmd(int argc, char **argv)
-{
-       if (argc <= 2)
-               return unsetcmd(argc, argv);
-       else if (argc == 3)
-               setvar(argv[1], argv[2], 0);
-       else
-               error("List assignment not implemented");
-       return 0;
-}
+#define TOK_UMINUS tok_decl(UNARYPREC+1,0)
+#define TOK_UPLUS tok_decl(UNARYPREC+1,1)
 
+#define PREC_PRE (UNARYPREC+2)
 
-/*
- * The unset builtin command.  We unset the function before we unset the
- * variable to allow a function to be unset when there is a readonly variable
- * with the same name.
- */
+#define TOK_PRE_INC tok_decl(PREC_PRE, 0)
+#define TOK_PRE_DEC tok_decl(PREC_PRE, 1)
 
-static int
-unsetcmd(int argc, char **argv)
-{
-       char **ap;
-       int i;
-       int flg_func = 0;
-       int flg_var = 0;
-       int ret = 0;
+#define PREC_POST (UNARYPREC+3)
 
-       while ((i = nextopt("vf")) != '\0') {
-               if (i == 'f')
-                       flg_func = 1;
-               else
-                       flg_var = 1;
-       }
-       if (flg_func == 0 && flg_var == 0)
-               flg_var = 1;
+#define TOK_POST_INC tok_decl(PREC_POST, 0)
+#define TOK_POST_DEC tok_decl(PREC_POST, 1)
 
-       for (ap = argptr; *ap ; ap++) {
-               if (flg_func)
-                       unsetfunc(*ap);
-               if (flg_var)
-                       ret |= unsetvar(*ap);
-       }
-       return ret;
-}
+#define SPEC_PREC (UNARYPREC+4)
 
+#define TOK_NUM tok_decl(SPEC_PREC, 0)
+#define TOK_RPAREN tok_decl(SPEC_PREC, 1)
 
-/*
- * Unset the specified variable.
- */
+#define NUMPTR (*numstackptr)
 
-static int
-unsetvar(const char *s)
+static inline int tok_have_assign(operator op)
 {
-       struct var **vpp;
-       struct var *vp;
+       operator prec = PREC(op);
 
-       vpp = findvar(hashvar(s), s);
-       vp = *vpp;
-       if (vp) {
-               if (vp->flags & VREADONLY)
-                       return (1);
-               INTOFF;
-               if (*(strchr(vp->text, '=') + 1) != '\0')
-                       setvar(s, nullstr, 0);
-               vp->flags &= ~VEXPORT;
-               vp->flags |= VUNSET;
-               if ((vp->flags & VSTRFIXED) == 0) {
-                       if ((vp->flags & VTEXTFIXED) == 0)
-                               ckfree(vp->text);
-                       *vpp = vp->next;
-                       ckfree(vp);
-               }
-               INTON;
-               return (0);
-       }
+       convert_prec_is_assing(prec);
+       return (prec == PREC(TOK_ASSIGN) ||
+                       prec == PREC_PRE || prec == PREC_POST);
+}
 
-       return (0);
+static inline int is_right_associativity(operator prec)
+{
+    return (prec == PREC(TOK_ASSIGN) || prec == PREC(TOK_EXPONENT) ||
+           prec == PREC(TOK_CONDITIONAL));
 }
 
 
+typedef struct ARITCH_VAR_NUM {
+       arith_t val;
+       arith_t contidional_second_val;
+       char contidional_second_val_initialized;
+       char *var;      /* if NULL then is regular number,
+                          else is variable name */
+} v_n_t;
 
-/*
- * Find the appropriate entry in the hash table from the name.
- */
 
-static struct var **
-hashvar(const char *p)
-{
-       unsigned int hashval;
+typedef struct CHK_VAR_RECURSIVE_LOOPED {
+       const char *var;
+       struct CHK_VAR_RECURSIVE_LOOPED *next;
+} chk_var_recursive_looped_t;
 
-       hashval = ((unsigned char) *p) << 4;
-       while (*p && *p != '=')
-               hashval += (unsigned char) *p++;
-       return &vartab[hashval % VTABSIZE];
-}
+static chk_var_recursive_looped_t *prev_chk_var_recursive;
 
 
+static int arith_lookup_val(v_n_t *t)
+{
+    if(t->var) {
+       const char * p = lookupvar(t->var);
 
-/*
- * Returns true if the two strings specify the same varable.  The first
- * variable name is terminated by '='; the second may be terminated by
- * either '=' or '\0'.
- */
+       if(p) {
+           int errcode;
 
-static int
-varequal(const char *p, const char *q)
-{
-       while (*p == *q++) {
-               if (*p++ == '=')
-                       return 1;
+           /* recursive try as expression */
+           chk_var_recursive_looped_t *cur;
+           chk_var_recursive_looped_t cur_save;
+
+           for(cur = prev_chk_var_recursive; cur; cur = cur->next) {
+               if(strcmp(cur->var, t->var) == 0) {
+                   /* expression recursion loop detected */
+                   return -5;
+               }
+           }
+           /* save current lookuped var name */
+           cur = prev_chk_var_recursive;
+           cur_save.var = t->var;
+           cur_save.next = cur;
+           prev_chk_var_recursive = &cur_save;
+
+           t->val = arith (p, &errcode);
+           /* restore previous ptr after recursiving */
+           prev_chk_var_recursive = cur;
+           return errcode;
+       } else {
+           /* allow undefined var as 0 */
+           t->val = 0;
        }
-       if (*p == '=' && *(q - 1) == '\0')
-               return 1;
-       return 0;
+    }
+    return 0;
 }
 
-static void
-showvars(const char *myprefix, int mask, int xor)
+/* "applying" a token means performing it on the top elements on the integer
+ * stack. For a unary operator it will only change the top element, but a
+ * binary operator will pop two arguments and push a result */
+static inline int
+arith_apply(operator op, v_n_t *numstack, v_n_t **numstackptr)
+{
+       v_n_t *numptr_m1;
+       arith_t numptr_val, rez;
+       int ret_arith_lookup_val;
+
+       if (NUMPTR == numstack) goto err; /* There is no operator that can work
+                                                                                without arguments */
+       numptr_m1 = NUMPTR - 1;
+
+       /* check operand is var with noninteger value */
+       ret_arith_lookup_val = arith_lookup_val(numptr_m1);
+       if(ret_arith_lookup_val)
+               return ret_arith_lookup_val;
+
+       rez = numptr_m1->val;
+       if (op == TOK_UMINUS)
+               rez *= -1;
+       else if (op == TOK_NOT)
+               rez = !rez;
+       else if (op == TOK_BNOT)
+               rez = ~rez;
+       else if (op == TOK_POST_INC || op == TOK_PRE_INC)
+               rez++;
+       else if (op == TOK_POST_DEC || op == TOK_PRE_DEC)
+               rez--;
+       else if (op != TOK_UPLUS) {
+               /* Binary operators */
+
+           /* check and binary operators need two arguments */
+           if (numptr_m1 == numstack) goto err;
+
+           /* ... and they pop one */
+           --NUMPTR;
+           numptr_val = rez;
+           if (op == TOK_CONDITIONAL) {
+               if(! numptr_m1->contidional_second_val_initialized) {
+                   /* protect $((expr1 ? expr2)) without ": expr" */
+                   goto err;
+               }
+               rez = numptr_m1->contidional_second_val;
+           } else if(numptr_m1->contidional_second_val_initialized) {
+                   /* protect $((expr1 : expr2)) without "expr ? " */
+                   goto err;
+           }
+           numptr_m1 = NUMPTR - 1;
+           if(op != TOK_ASSIGN) {
+               /* check operand is var with noninteger value for not '=' */
+               ret_arith_lookup_val = arith_lookup_val(numptr_m1);
+               if(ret_arith_lookup_val)
+                   return ret_arith_lookup_val;
+           }
+           if (op == TOK_CONDITIONAL) {
+                   numptr_m1->contidional_second_val = rez;
+           }
+           rez = numptr_m1->val;
+           if (op == TOK_BOR || op == TOK_OR_ASSIGN)
+                       rez |= numptr_val;
+           else if (op == TOK_OR)
+                       rez = numptr_val || rez;
+           else if (op == TOK_BAND || op == TOK_AND_ASSIGN)
+                       rez &= numptr_val;
+           else if (op == TOK_BXOR || op == TOK_XOR_ASSIGN)
+                       rez ^= numptr_val;
+           else if (op == TOK_AND)
+                       rez = rez && numptr_val;
+           else if (op == TOK_EQ)
+                       rez = (rez == numptr_val);
+           else if (op == TOK_NE)
+                       rez = (rez != numptr_val);
+           else if (op == TOK_GE)
+                       rez = (rez >= numptr_val);
+           else if (op == TOK_RSHIFT || op == TOK_RSHIFT_ASSIGN)
+                       rez >>= numptr_val;
+           else if (op == TOK_LSHIFT || op == TOK_LSHIFT_ASSIGN)
+                       rez <<= numptr_val;
+           else if (op == TOK_GT)
+                       rez = (rez > numptr_val);
+           else if (op == TOK_LT)
+                       rez = (rez < numptr_val);
+           else if (op == TOK_LE)
+                       rez = (rez <= numptr_val);
+           else if (op == TOK_MUL || op == TOK_MUL_ASSIGN)
+                       rez *= numptr_val;
+           else if (op == TOK_ADD || op == TOK_PLUS_ASSIGN)
+                       rez += numptr_val;
+           else if (op == TOK_SUB || op == TOK_MINUS_ASSIGN)
+                       rez -= numptr_val;
+           else if (op == TOK_ASSIGN || op == TOK_COMMA)
+                       rez = numptr_val;
+           else if (op == TOK_CONDITIONAL_SEP) {
+                       if (numptr_m1 == numstack) {
+                           /* protect $((expr : expr)) without "expr ? " */
+                           goto err;
+                       }
+                       numptr_m1->contidional_second_val_initialized = op;
+                       numptr_m1->contidional_second_val = numptr_val;
+           }
+           else if (op == TOK_CONDITIONAL) {
+                       rez = rez ?
+                             numptr_val : numptr_m1->contidional_second_val;
+           }
+           else if(op == TOK_EXPONENT) {
+                       if(numptr_val < 0)
+                               return -3;      /* exponent less than 0 */
+                       else {
+                               arith_t c = 1;
+
+                               if(numptr_val)
+                                       while(numptr_val--)
+                                               c *= rez;
+                               rez = c;
+                       }
+           }
+           else if(numptr_val==0)          /* zero divisor check */
+                       return -2;
+           else if (op == TOK_DIV || op == TOK_DIV_ASSIGN)
+                       rez /= numptr_val;
+           else if (op == TOK_REM || op == TOK_REM_ASSIGN)
+                       rez %= numptr_val;
+       }
+       if(tok_have_assign(op)) {
+               char buf[32];
+
+               if(numptr_m1->var == NULL) {
+                       /* Hmm, 1=2 ? */
+                       goto err;
+               }
+               /* save to shell variable */
+#ifdef CONFIG_ASH_MATH_SUPPORT_64
+               snprintf(buf, sizeof(buf), "%lld", arith_t_type rez);
+#else
+               snprintf(buf, sizeof(buf), "%ld", arith_t_type rez);
+#endif
+               setvar(numptr_m1->var, buf, 0);
+               /* after saving, make previous value for v++ or v-- */
+               if(op == TOK_POST_INC)
+                       rez--;
+               else if(op == TOK_POST_DEC)
+                       rez++;
+       }
+       numptr_m1->val = rez;
+       /* protect geting var value, is number now */
+       numptr_m1->var = NULL;
+       return 0;
+err: return(-1);
+}
+
+/* longest must first */
+static const char op_tokens[] = {
+       '<','<','=',0, TOK_LSHIFT_ASSIGN,
+       '>','>','=',0, TOK_RSHIFT_ASSIGN,
+       '<','<',    0, TOK_LSHIFT,
+       '>','>',    0, TOK_RSHIFT,
+       '|','|',    0, TOK_OR,
+       '&','&',    0, TOK_AND,
+       '!','=',    0, TOK_NE,
+       '<','=',    0, TOK_LE,
+       '>','=',    0, TOK_GE,
+       '=','=',    0, TOK_EQ,
+       '|','=',    0, TOK_OR_ASSIGN,
+       '&','=',    0, TOK_AND_ASSIGN,
+       '*','=',    0, TOK_MUL_ASSIGN,
+       '/','=',    0, TOK_DIV_ASSIGN,
+       '%','=',    0, TOK_REM_ASSIGN,
+       '+','=',    0, TOK_PLUS_ASSIGN,
+       '-','=',    0, TOK_MINUS_ASSIGN,
+       '-','-',    0, TOK_POST_DEC,
+       '^','=',    0, TOK_XOR_ASSIGN,
+       '+','+',    0, TOK_POST_INC,
+       '*','*',    0, TOK_EXPONENT,
+       '!',        0, TOK_NOT,
+       '<',        0, TOK_LT,
+       '>',        0, TOK_GT,
+       '=',        0, TOK_ASSIGN,
+       '|',        0, TOK_BOR,
+       '&',        0, TOK_BAND,
+       '*',        0, TOK_MUL,
+       '/',        0, TOK_DIV,
+       '%',        0, TOK_REM,
+       '+',        0, TOK_ADD,
+       '-',        0, TOK_SUB,
+       '^',        0, TOK_BXOR,
+       /* uniq */
+       '~',        0, TOK_BNOT,
+       ',',        0, TOK_COMMA,
+       '?',        0, TOK_CONDITIONAL,
+       ':',        0, TOK_CONDITIONAL_SEP,
+       ')',        0, TOK_RPAREN,
+       '(',        0, TOK_LPAREN,
+       0
+};
+/* ptr to ")" */
+#define endexpression &op_tokens[sizeof(op_tokens)-7]
+
+
+static arith_t arith (const char *expr, int *perrcode)
 {
-       struct var **vpp;
-       struct var *vp;
-       const char *sep = myprefix == nullstr ? myprefix : spcstr;
+    char arithval; /* Current character under analysis */
+    operator lasttok, op;
+    operator prec;
 
-       for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
-               for (vp = *vpp ; vp ; vp = vp->next) {
-                       if ((vp->flags & mask) ^ xor) {
-                               char *p;
-                               int len;
+    const char *p = endexpression;
+    int errcode;
 
-                               p = strchr(vp->text, '=') + 1;
-                               len = p - vp->text;
-                               p = single_quote(p);
+    size_t datasizes = strlen(expr) + 2;
 
-                               printf("%s%s%.*s%s\n", myprefix, sep, len,
-                                       vp->text, p);
-                               stunalloc(p);
-                       }
-               }
-       }
-}
+    /* Stack of integers */
+    /* The proof that there can be no more than strlen(startbuf)/2+1 integers
+     * in any given correct or incorrect expression is left as an exercise to
+     * the reader. */
+    v_n_t *numstack = alloca(((datasizes)/2)*sizeof(v_n_t)),
+           *numstackptr = numstack;
+    /* Stack of operator tokens */
+    operator *stack = alloca((datasizes) * sizeof(operator)),
+           *stackptr = stack;
 
-static struct var **
-findvar(struct var **vpp, const char *name)
-{
-       for (; *vpp; vpp = &(*vpp)->next) {
-               if (varequal((*vpp)->text, name)) {
-                       break;
+    *stackptr++ = lasttok = TOK_LPAREN;     /* start off with a left paren */
+    *perrcode = errcode = 0;
+
+    while(1) {
+       if ((arithval = *expr) == 0) {
+               if (p == endexpression) {
+                       /* Null expression. */
+                       return 0;
                }
-       }
-       return vpp;
-}
 
-/*
- * Copyright (c) 1999 Herbert Xu <herbert@debian.org>
- * This file contains code for the times builtin.
- * $Id: ash.c,v 1.49 2002/04/26 23:39:48 andersen Exp $
- */
-static int timescmd (int argc, char **argv)
-{
-       struct tms buf;
-       long int clk_tck = sysconf(_SC_CLK_TCK);
+               /* This is only reached after all tokens have been extracted from the
+                * input stream. If there are still tokens on the operator stack, they
+                * are to be applied in order. At the end, there should be a final
+                * result on the integer stack */
 
-       times(&buf);
-       printf("%dm%fs %dm%fs\n%dm%fs %dm%fs\n",
-              (int) (buf.tms_utime / clk_tck / 60),
-              ((double) buf.tms_utime) / clk_tck,
-              (int) (buf.tms_stime / clk_tck / 60),
-              ((double) buf.tms_stime) / clk_tck,
-              (int) (buf.tms_cutime / clk_tck / 60),
-              ((double) buf.tms_cutime) / clk_tck,
-              (int) (buf.tms_cstime / clk_tck / 60),
-              ((double) buf.tms_cstime) / clk_tck);
-       return 0;
-}
+               if (expr != endexpression + 1) {
+                       /* If we haven't done so already, */
+                       /* append a closing right paren */
+                       expr = endexpression;
+                       /* and let the loop process it. */
+                       continue;
+               }
+               /* At this point, we're done with the expression. */
+               if (numstackptr != numstack+1) {
+                       /* ... but if there isn't, it's bad */
+                 err:
+                       return (*perrcode = -1);
+               }
+               if(numstack->var) {
+                   /* expression is $((var)) only, lookup now */
+                   errcode = arith_lookup_val(numstack);
+               }
+       ret:
+               *perrcode = errcode;
+               return numstack->val;
+       } else {
+               /* Continue processing the expression. */
+               if (arith_isspace(arithval)) {
+                       /* Skip whitespace */
+                       goto prologue;
+               }
+               if((p = endofname(expr)) != expr) {
+                       size_t var_name_size = (p-expr) + 1;  /* trailing zero */
+
+                       numstackptr->var = alloca(var_name_size);
+                       safe_strncpy(numstackptr->var, expr, var_name_size);
+                       expr = p;
+               num:
+                       numstackptr->contidional_second_val_initialized = 0;
+                       numstackptr++;
+                       lasttok = TOK_NUM;
+                       continue;
+               } else if (is_digit(arithval)) {
+                       numstackptr->var = NULL;
+#ifdef CONFIG_ASH_MATH_SUPPORT_64
+                       numstackptr->val = strtoll(expr, (char **) &expr, 0);
+#else
+                       numstackptr->val = strtol(expr, (char **) &expr, 0);
+#endif
+                       goto num;
+               }
+               for(p = op_tokens; ; p++) {
+                       const char *o;
 
-#ifdef CONFIG_ASH_MATH_SUPPORT
-/* The let builtin.  */
-int letcmd(int argc, char **argv)
-{
-       int errcode;
-       long result=0;
-       if (argc == 2) {
-               char *tmp, *expression, p[13];
-               expression = strchr(argv[1], '=');
-               if (!expression) {
-                       /* Cannot use 'error()' here, or the return code
-                        * will be incorrect */
-                       out2fmt("sh: let: syntax error: \"%s\"\n", argv[1]);
-                       return 0;
+                       if(*p == 0) {
+                               /* strange operator not found */
+                               goto err;
+                       }
+                       for(o = expr; *p && *o == *p; p++)
+                               o++;
+                       if(! *p) {
+                               /* found */
+                               expr = o - 1;
+                               break;
+                       }
+                       /* skip tail uncompared token */
+                       while(*p)
+                               p++;
+                       /* skip zero delim */
+                       p++;
                }
-               *expression = '\0';
-               tmp = ++expression;
-               result = arith(tmp, &errcode);
-               if (errcode < 0) {
-                       /* Cannot use 'error()' here, or the return code
-                        * will be incorrect */
-                       out2fmt("sh: let: ");
-                       if(errcode == -2)
-                               out2fmt("divide by zero");
-                       else
-                               out2fmt("syntax error: \"%s=%s\"\n", argv[1], expression);
-                       return 0;
+               op = p[1];
+
+               /* post grammar: a++ reduce to num */
+               if(lasttok == TOK_POST_INC || lasttok == TOK_POST_DEC)
+                   lasttok = TOK_NUM;
+
+               /* Plus and minus are binary (not unary) _only_ if the last
+                * token was as number, or a right paren (which pretends to be
+                * a number, since it evaluates to one). Think about it.
+                * It makes sense. */
+               if (lasttok != TOK_NUM) {
+                       switch(op) {
+                               case TOK_ADD:
+                                   op = TOK_UPLUS;
+                                   break;
+                               case TOK_SUB:
+                                   op = TOK_UMINUS;
+                                   break;
+                               case TOK_POST_INC:
+                                   op = TOK_PRE_INC;
+                                   break;
+                               case TOK_POST_DEC:
+                                   op = TOK_PRE_DEC;
+                                   break;
+                       }
+               }
+               /* We don't want a unary operator to cause recursive descent on the
+                * stack, because there can be many in a row and it could cause an
+                * operator to be evaluated before its argument is pushed onto the
+                * integer stack. */
+               /* But for binary operators, "apply" everything on the operator
+                * stack until we find an operator with a lesser priority than the
+                * one we have just extracted. */
+               /* Left paren is given the lowest priority so it will never be
+                * "applied" in this way.
+                * if associativity is right and priority eq, applied also skip
+                */
+               prec = PREC(op);
+               if ((prec > 0 && prec < UNARYPREC) || prec == SPEC_PREC) {
+                       /* not left paren or unary */
+                       if (lasttok != TOK_NUM) {
+                               /* binary op must be preceded by a num */
+                               goto err;
+                       }
+                       while (stackptr != stack) {
+                           if (op == TOK_RPAREN) {
+                               /* The algorithm employed here is simple: while we don't
+                                * hit an open paren nor the bottom of the stack, pop
+                                * tokens and apply them */
+                               if (stackptr[-1] == TOK_LPAREN) {
+                                   --stackptr;
+                                   /* Any operator directly after a */
+                                   lasttok = TOK_NUM;
+                                   /* close paren should consider itself binary */
+                                   goto prologue;
+                               }
+                           } else {
+                               operator prev_prec = PREC(stackptr[-1]);
+
+                               convert_prec_is_assing(prec);
+                               convert_prec_is_assing(prev_prec);
+                               if (prev_prec < prec)
+                                       break;
+                               /* check right assoc */
+                               if(prev_prec == prec && is_right_associativity(prec))
+                                       break;
+                           }
+                           errcode = arith_apply(*--stackptr, numstack, &numstackptr);
+                           if(errcode) goto ret;
+                       }
+                       if (op == TOK_RPAREN) {
+                               goto err;
+                       }
                }
-               snprintf(p, 12, "%ld", result);
-               setvar(argv[1], xstrdup(p), 0);
-       } else if (argc >= 3)
-               synerror("invalid operand");
-       return !result;
+
+               /* Push this operator to the stack and remember it. */
+               *stackptr++ = lasttok = op;
+
+         prologue:
+               ++expr;
+       }
+    }
 }
-#endif
+#endif /* CONFIG_ASH_MATH_SUPPORT */
 
 
+#ifdef DEBUG
+const char *bb_applet_name = "debug stuff usage";
+int main(int argc, char **argv)
+{
+       return ash_main(argc, argv);
+}
+#endif
 
 /*-
  * Copyright (c) 1989, 1991, 1993, 1994
@@ -12508,11 +13666,7 @@ int letcmd(int argc, char **argv)
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
- *
- * 3. <BSD Advertising Clause omitted per the July 22, 1999 licensing change
- *              ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change>
- *
- * 4. Neither the name of the University nor the names of its contributors
+ * 3. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *