common/hush.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * sh.c -- a prototype Bourne shell grammar parser
   4  *      Intended to follow the original Thompson and Ritchie
   5  *      "small and simple is beautiful" philosophy, which
   6  *      incidentally is a good match to today's BusyBox.
   7  *
   8  * Copyright (C) 2000,2001  Larry Doolittle  <larry@doolittle.boa.org>
   9  *
  10  * Credits:
  11  *      The parser routines proper are all original material, first
  12  *      written Dec 2000 and Jan 2001 by Larry Doolittle.
  13  *      The execution engine, the builtins, and much of the underlying
  14  *      support has been adapted from busybox-0.49pre's lash,
  15  *      which is Copyright (C) 2000 by Lineo, Inc., and
  16  *      written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>.
  17  *      That, in turn, is based in part on ladsh.c, by Michael K. Johnson and
  18  *      Erik W. Troan, which they placed in the public domain.  I don't know
  19  *      how much of the Johnson/Troan code has survived the repeated rewrites.
  20  * Other credits:
  21  *      simple_itoa() was lifted from boa-0.93.15
  22  *      b_addchr() derived from similar w_addchar function in glibc-2.2
  23  *      setup_redirect(), redirect_opt_num(), and big chunks of main()
  24  *        and many builtins derived from contributions by Erik Andersen
  25  *      miscellaneous bugfixes from Matt Kraai
  26  *
  27  * There are two big (and related) architecture differences between
  28  * this parser and the lash parser.  One is that this version is
  29  * actually designed from the ground up to understand nearly all
  30  * of the Bourne grammar.  The second, consequential change is that
  31  * the parser and input reader have been turned inside out.  Now,
  32  * the parser is in control, and asks for input as needed.  The old
  33  * way had the input reader in control, and it asked for parsing to
  34  * take place as needed.  The new way makes it much easier to properly
  35  * handle the recursion implicit in the various substitutions, especially
  36  * across continuation lines.
  37  *
  38  * Bash grammar not implemented: (how many of these were in original sh?)
  39  *      $@ (those sure look like weird quoting rules)
  40  *      $_
  41  *      ! negation operator for pipes
  42  *      &> and >& redirection of stdout+stderr
  43  *      Brace Expansion
  44  *      Tilde Expansion
  45  *      fancy forms of Parameter Expansion
  46  *      aliases
  47  *      Arithmetic Expansion
  48  *      <(list) and >(list) Process Substitution
  49  *      reserved words: case, esac, select, function
  50  *      Here Documents ( << word )
  51  *      Functions
  52  * Major bugs:
  53  *      job handling woefully incomplete and buggy
  54  *      reserved word execution woefully incomplete and buggy
  55  * to-do:
  56  *      port selected bugfixes from post-0.49 busybox lash - done?
  57  *      finish implementing reserved words: for, while, until, do, done
  58  *      change { and } from special chars to reserved words
  59  *      builtins: break, continue, eval, return, set, trap, ulimit
  60  *      test magic exec
  61  *      handle children going into background
  62  *      clean up recognition of null pipes
  63  *      check setting of global_argc and global_argv
  64  *      control-C handling, probably with longjmp
  65  *      follow IFS rules more precisely, including update semantics
  66  *      figure out what to do with backslash-newline
  67  *      explain why we use signal instead of sigaction
  68  *      propagate syntax errors, die on resource errors?
  69  *      continuation lines, both explicit and implicit - done?
  70  *      memory leak finding and plugging - done?
  71  *      more testing, especially quoting rules and redirection
  72  *      document how quoting rules not precisely followed for variable assignments
  73  *      maybe change map[] to use 2-bit entries
  74  *      (eventually) remove all the printf's
  75  *
  76  * This program is free software; you can redistribute it and/or modify
  77  * it under the terms of the GNU General Public License as published by
  78  * the Free Software Foundation; either version 2 of the License, or
  79  * (at your option) any later version.
  80  *
  81  * This program is distributed in the hope that it will be useful,
  82  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  83  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  84  * General Public License for more details.
  85  *
  86  * You should have received a copy of the GNU General Public License
  87  * along with this program; if not, write to the Free Software
  88  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  89  */
  90 #define __U_BOOT__
  91 #ifdef __U_BOOT__
  92 #include <malloc.h>         /* malloc, free, realloc*/
  93 #include <linux/ctype.h>    /* isalpha, isdigit */
  94 #include <common.h>        /* readline */
  95 #include <hush.h>
  96 #include <command.h>        /* find_cmd */
  97 /*cmd_boot.c*/
  98 extern int do_bootd (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]);      /* do_bootd */
  99 #endif
 100 #ifdef CFG_HUSH_PARSER
 101 #ifndef __U_BOOT__
 102 #include <ctype.h>     /* isalpha, isdigit */
 103 #include <unistd.h>    /* getpid */
 104 #include <stdlib.h>    /* getenv, atoi */
 105 #include <string.h>    /* strchr */
 106 #include <stdio.h>     /* popen etc. */
 107 #include <glob.h>      /* glob, of course */
 108 #include <stdarg.h>    /* va_list */
 109 #include <errno.h>
 110 #include <fcntl.h>
 111 #include <getopt.h>    /* should be pretty obvious */
 112
 113 #include <sys/stat.h>  /* ulimit */
 114 #include <sys/types.h>
 115 #include <sys/wait.h>
 116 #include <signal.h>
 117
 118 /* #include <dmalloc.h> */
 119 /* #define DEBUG_SHELL */
 120
 121 #if 1
 122 #include "busybox.h"
 123 #include "cmdedit.h"
 124 #else
 125 #define applet_name "hush"
 126 #include "standalone.h"
 127 #define hush_main main
 128 #undef CONFIG_FEATURE_SH_FANCY_PROMPT
 129 #define BB_BANNER
 130 #endif
 131 #endif
 132 #define SPECIAL_VAR_SYMBOL 03
 133 #ifndef __U_BOOT__
 134 #define FLAG_EXIT_FROM_LOOP 1
 135 #define FLAG_PARSE_SEMICOLON (1 << 1)           /* symbol ';' is special for parser */
 136 #define FLAG_REPARSING       (1 << 2)           /* >= 2nd pass */
 137
 138 #endif
 139
 140 #ifdef __U_BOOT__
 141 #define EXIT_SUCCESS 0
 142 #define EOF -1
 143 #define syntax() syntax_err()
 144 #define xstrdup strdup
 145 #define error_msg printf
 146 #else
 147 typedef enum {
 148         REDIRECT_INPUT     = 1,
 149         REDIRECT_OVERWRITE = 2,
 150         REDIRECT_APPEND    = 3,
 151         REDIRECT_HEREIS    = 4,
 152         REDIRECT_IO        = 5
 153 } redir_type;
 154
 155 /* The descrip member of this structure is only used to make debugging
 156  * output pretty */
 157 struct {int mode; int default_fd; char *descrip;} redir_table[] = {
 158         { 0,                         0, "()" },
 159         { O_RDONLY,                  0, "<"  },
 160         { O_CREAT|O_TRUNC|O_WRONLY,  1, ">"  },
 161         { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
 162         { O_RDONLY,                 -1, "<<" },
 163         { O_RDWR,                    1, "<>" }
 164 };
 165 #endif
 166
 167 typedef enum {
 168         PIPE_SEQ = 1,
 169         PIPE_AND = 2,
 170         PIPE_OR  = 3,
 171         PIPE_BG  = 4,
 172 } pipe_style;
 173
 174 /* might eventually control execution */
 175 typedef enum {
 176         RES_NONE  = 0,
 177         RES_IF    = 1,
 178         RES_THEN  = 2,
 179         RES_ELIF  = 3,
 180         RES_ELSE  = 4,
 181         RES_FI    = 5,
 182         RES_FOR   = 6,
 183         RES_WHILE = 7,
 184         RES_UNTIL = 8,
 185         RES_DO    = 9,
 186         RES_DONE  = 10,
 187         RES_XXXX  = 11,
 188         RES_IN    = 12,
 189         RES_SNTX  = 13
 190 } reserved_style;
 191 #define FLAG_END   (1<<RES_NONE)
 192 #define FLAG_IF    (1<<RES_IF)
 193 #define FLAG_THEN  (1<<RES_THEN)
 194 #define FLAG_ELIF  (1<<RES_ELIF)
 195 #define FLAG_ELSE  (1<<RES_ELSE)
 196 #define FLAG_FI    (1<<RES_FI)
 197 #define FLAG_FOR   (1<<RES_FOR)
 198 #define FLAG_WHILE (1<<RES_WHILE)
 199 #define FLAG_UNTIL (1<<RES_UNTIL)
 200 #define FLAG_DO    (1<<RES_DO)
 201 #define FLAG_DONE  (1<<RES_DONE)
 202 #define FLAG_IN    (1<<RES_IN)
 203 #define FLAG_START (1<<RES_XXXX)
 204
 205 /* This holds pointers to the various results of parsing */
 206 struct p_context {
 207         struct child_prog *child;
 208         struct pipe *list_head;
 209         struct pipe *pipe;
 210 #ifndef __U_BOOT__
 211         struct redir_struct *pending_redirect;
 212 #endif
 213         reserved_style w;
 214         int old_flag;                           /* for figuring out valid reserved words */
 215         struct p_context *stack;
 216         int type;                       /* define type of parser : ";$" common or special symbol */
 217         /* How about quoting status? */
 218 };
 219
 220 #ifndef __U_BOOT__
 221 struct redir_struct {
 222         redir_type type;                        /* type of redirection */
 223         int fd;                                         /* file descriptor being redirected */
 224         int dup;                                        /* -1, or file descriptor being duplicated */
 225         struct redir_struct *next;      /* pointer to the next redirect in the list */
 226         glob_t word;                            /* *word.gl_pathv is the filename */
 227 };
 228 #endif
 229
 230 struct child_prog {
 231 #ifndef __U_BOOT__
 232         pid_t pid;                                      /* 0 if exited */
 233 #endif
 234         char **argv;                            /* program name and arguments */
 235 #ifdef __U_BOOT__
 236         int    argc;                            /* number of program arguments */
 237 #endif
 238         struct pipe *group;                     /* if non-NULL, first in group or subshell */
 239 #ifndef __U_BOOT__
 240         int subshell;                           /* flag, non-zero if group must be forked */
 241         struct redir_struct *redirects; /* I/O redirections */
 242         glob_t glob_result;                     /* result of parameter globbing */
 243         int is_stopped;                         /* is the program currently running? */
 244         struct pipe *family;            /* pointer back to the child's parent pipe */
 245 #endif
 246         int sp;                         /* number of SPECIAL_VAR_SYMBOL */
 247         int type;
 248 };
 249
 250 struct pipe {
 251 #ifndef __U_BOOT__
 252         int jobid;                                      /* job number */
 253 #endif
 254         int num_progs;                          /* total number of programs in job */
 255 #ifndef __U_BOOT__
 256         int running_progs;                      /* number of programs running */
 257         char *text;                                     /* name of job */
 258         char *cmdbuf;                           /* buffer various argv's point into */
 259         pid_t pgrp;                                     /* process group ID for the job */
 260 #endif
 261         struct child_prog *progs;       /* array of commands in pipe */
 262         struct pipe *next;                      /* to track background commands */
 263 #ifndef __U_BOOT__
 264         int stopped_progs;                      /* number of programs alive, but stopped */
 265         int job_context;                        /* bitmask defining current context */
 266 #endif
 267         pipe_style followup;            /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
 268         reserved_style r_mode;          /* supports if, for, while, until */
 269 };
 270
 271 #ifndef __U_BOOT__
 272 struct close_me {
 273         int fd;
 274         struct close_me *next;
 275 };
 276 #endif
 277
 278 struct variables {
 279         char *name;
 280         char *value;
 281         int flg_export;
 282         int flg_read_only;
 283         struct variables *next;
 284 };
 285
 286 /* globals, connect us to the outside world
 287  * the first three support $?, $#, and $1 */
 288 #ifndef __U_BOOT__
 289 char **global_argv;
 290 unsigned int global_argc;
 291 #endif
 292 unsigned int last_return_code;
 293 #ifndef __U_BOOT__
 294 extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
 295 #endif
 296
 297 /* "globals" within this file */
 298 static char *ifs;
 299 static char map[256];
 300 #ifndef __U_BOOT__
 301 static int fake_mode;
 302 static int interactive;
 303 static struct close_me *close_me_head;
 304 static const char *cwd;
 305 static struct pipe *job_list;
 306 static unsigned int last_bg_pid;
 307 static unsigned int last_jobid;
 308 static unsigned int shell_terminal;
 309 static char *PS1;
 310 static char *PS2;
 311 struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
 312 struct variables *top_vars = &shell_ver;
 313 #else
 314 static int flag_repeat = 0;
 315 static int do_repeat = 0;
 316 static struct variables *top_vars = NULL ;
 317 #endif /*__U_BOOT__ */
 318
 319 #define B_CHUNK (100)
 320 #define B_NOSPAC 1
 321
 322 typedef struct {
 323         char *data;
 324         int length;
 325         int maxlen;
 326         int quote;
 327         int nonnull;
 328 } o_string;
 329 #define NULL_O_STRING {NULL,0,0,0,0}
 330 /* used for initialization:
 331         o_string foo = NULL_O_STRING; */
 332
 333 /* I can almost use ordinary FILE *.  Is open_memstream() universally
 334  * available?  Where is it documented? */
 335 struct in_str {
 336         const char *p;
 337 #ifndef __U_BOOT__
 338         char peek_buf[2];
 339 #endif
 340         int __promptme;
 341         int promptmode;
 342 #ifndef __U_BOOT__
 343         FILE *file;
 344 #endif
 345         int (*get) (struct in_str *);
 346         int (*peek) (struct in_str *);
 347 };
 348 #define b_getch(input) ((input)->get(input))
 349 #define b_peek(input) ((input)->peek(input))
 350
 351 #ifndef __U_BOOT__
 352 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
 353
 354 struct built_in_command {
 355         char *cmd;                                      /* name */
 356         char *descr;                            /* description */
 357         int (*function) (struct child_prog *);  /* function ptr */
 358 };
 359 #endif
 360
 361 /* This should be in utility.c */
 362 #ifdef DEBUG_SHELL
 363 #ifndef __U_BOOT__
 364 static void debug_printf(const char *format, ...)
 365 {
 366         va_list args;
 367         va_start(args, format);
 368         vfprintf(stderr, format, args);
 369         va_end(args);
 370 }
 371 #else
 372 #define debug_printf printf             /* U-Boot debug flag */
 373 #endif
 374 #else
 375 static inline void debug_printf(const char *format, ...) { }
 376 #endif
 377 #define final_printf debug_printf
 378
 379 #ifdef __U_BOOT__
 380 static void syntax_err(void) {
 381          printf("syntax error\n");
 382 }
 383 #else
 384 static void __syntax(char *file, int line) {
 385         error_msg("syntax error %s:%d", file, line);
 386 }
 387 #define syntax() __syntax(__FILE__, __LINE__)
 388 #endif
 389
 390 #ifdef __U_BOOT__
 391 static void *xmalloc(size_t size);
 392 static void *xrealloc(void *ptr, size_t size);
 393 #else
 394 /* Index of subroutines: */
 395 /*   function prototypes for builtins */
 396 static int builtin_cd(struct child_prog *child);
 397 static int builtin_env(struct child_prog *child);
 398 static int builtin_eval(struct child_prog *child);
 399 static int builtin_exec(struct child_prog *child);
 400 static int builtin_exit(struct child_prog *child);
 401 static int builtin_export(struct child_prog *child);
 402 static int builtin_fg_bg(struct child_prog *child);
 403 static int builtin_help(struct child_prog *child);
 404 static int builtin_jobs(struct child_prog *child);
 405 static int builtin_pwd(struct child_prog *child);
 406 static int builtin_read(struct child_prog *child);
 407 static int builtin_set(struct child_prog *child);
 408 static int builtin_shift(struct child_prog *child);
 409 static int builtin_source(struct child_prog *child);
 410 static int builtin_umask(struct child_prog *child);
 411 static int builtin_unset(struct child_prog *child);
 412 static int builtin_not_written(struct child_prog *child);
 413 #endif
 414 /*   o_string manipulation: */
 415 static int b_check_space(o_string *o, int len);
 416 static int b_addchr(o_string *o, int ch);
 417 static void b_reset(o_string *o);
 418 static int b_addqchr(o_string *o, int ch, int quote);
 419 static int b_adduint(o_string *o, unsigned int i);
 420 /*  in_str manipulations: */
 421 static int static_get(struct in_str *i);
 422 static int static_peek(struct in_str *i);
 423 static int file_get(struct in_str *i);
 424 static int file_peek(struct in_str *i);
 425 #ifndef __U_BOOT__
 426 static void setup_file_in_str(struct in_str *i, FILE *f);
 427 #else
 428 static void setup_file_in_str(struct in_str *i);
 429 #endif
 430 static void setup_string_in_str(struct in_str *i, const char *s);
 431 #ifndef __U_BOOT__
 432 /*  close_me manipulations: */
 433 static void mark_open(int fd);
 434 static void mark_closed(int fd);
 435 static void close_all(void);
 436 #endif
 437 /*  "run" the final data structures: */
 438 static char *indenter(int i);
 439 static int free_pipe_list(struct pipe *head, int indent);
 440 static int free_pipe(struct pipe *pi, int indent);
 441 /*  really run the final data structures: */
 442 #ifndef __U_BOOT__
 443 static int setup_redirects(struct child_prog *prog, int squirrel[]);
 444 #endif
 445 static int run_list_real(struct pipe *pi);
 446 #ifndef __U_BOOT__
 447 static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
 448 #endif
 449 static int run_pipe_real(struct pipe *pi);
 450 /*   extended glob support: */
 451 #ifndef __U_BOOT__
 452 static int globhack(const char *src, int flags, glob_t *pglob);
 453 static int glob_needed(const char *s);
 454 static int xglob(o_string *dest, int flags, glob_t *pglob);
 455 #endif
 456 /*   variable assignment: */
 457 static int is_assignment(const char *s);
 458 /*   data structure manipulation: */
 459 #ifndef __U_BOOT__
 460 static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
 461 #endif
 462 static void initialize_context(struct p_context *ctx);
 463 static int done_word(o_string *dest, struct p_context *ctx);
 464 static int done_command(struct p_context *ctx);
 465 static int done_pipe(struct p_context *ctx, pipe_style type);
 466 /*   primary string parsing: */
 467 #ifndef __U_BOOT__
 468 static int redirect_dup_num(struct in_str *input);
 469 static int redirect_opt_num(o_string *o);
 470 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
 471 static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
 472 #endif
 473 static char *lookup_param(char *src);
 474 static char *make_string(char **inp);
 475 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
 476 #ifndef __U_BOOT__
 477 static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
 478 #endif
 479 static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
 480 /*   setup: */
 481 static int parse_stream_outer(struct in_str *inp, int flag);
 482 #ifndef __U_BOOT__
 483 static int parse_string_outer(const char *s, int flag);
 484 static int parse_file_outer(FILE *f);
 485 #endif
 486 #ifndef __U_BOOT__
 487 /*   job management: */
 488 static int checkjobs(struct pipe* fg_pipe);
 489 static void insert_bg_job(struct pipe *pi);
 490 static void remove_bg_job(struct pipe *pi);
 491 #endif
 492 /*     local variable support */
 493 static char **make_list_in(char **inp, char *name);
 494 static char *insert_var_value(char *inp);
 495 static char *get_local_var(const char *var);
 496 #ifndef __U_BOOT__
 497 static void  unset_local_var(const char *name);
 498 #endif
 499 static int set_local_var(const char *s, int flg_export);
 500
 501 #ifndef __U_BOOT__
 502 /* Table of built-in functions.  They can be forked or not, depending on
 503  * context: within pipes, they fork.  As simple commands, they do not.
 504  * When used in non-forking context, they can change global variables
 505  * in the parent shell process.  If forked, of course they can not.
 506  * For example, 'unset foo | whatever' will parse and run, but foo will
 507  * still be set at the end. */
 508 static struct built_in_command bltins[] = {
 509         {"bg", "Resume a job in the background", builtin_fg_bg},
 510         {"break", "Exit for, while or until loop", builtin_not_written},
 511         {"cd", "Change working directory", builtin_cd},
 512         {"continue", "Continue for, while or until loop", builtin_not_written},
 513         {"env", "Print all environment variables", builtin_env},
 514         {"eval", "Construct and run shell command", builtin_eval},
 515         {"exec", "Exec command, replacing this shell with the exec'd process",
 516                 builtin_exec},
 517         {"exit", "Exit from shell()", builtin_exit},
 518         {"export", "Set environment variable", builtin_export},
 519         {"fg", "Bring job into the foreground", builtin_fg_bg},
 520         {"jobs", "Lists the active jobs", builtin_jobs},
 521         {"pwd", "Print current directory", builtin_pwd},
 522         {"read", "Input environment variable", builtin_read},
 523         {"return", "Return from a function", builtin_not_written},
 524         {"set", "Set/unset shell local variables", builtin_set},
 525         {"shift", "Shift positional parameters", builtin_shift},
 526         {"trap", "Trap signals", builtin_not_written},
 527         {"ulimit","Controls resource limits", builtin_not_written},
 528         {"umask","Sets file creation mask", builtin_umask},
 529         {"unset", "Unset environment variable", builtin_unset},
 530         {".", "Source-in and run commands in a file", builtin_source},
 531         {"help", "List shell built-in commands", builtin_help},
 532         {NULL, NULL, NULL}
 533 };
 534
 535 static const char *set_cwd(void)
 536 {
 537         if(cwd==unknown)
 538                 cwd = NULL;     /* xgetcwd(arg) called free(arg) */
 539         cwd = xgetcwd((char *)cwd);
 540         if (!cwd)
 541                 cwd = unknown;
 542         return cwd;
 543 }
 544
 545 /* built-in 'eval' handler */
 546 static int builtin_eval(struct child_prog *child)
 547 {
 548         char *str = NULL;
 549         int rcode = EXIT_SUCCESS;
 550
 551         if (child->argv[1]) {
 552                 str = make_string(child->argv + 1);
 553                 parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
 554                                         FLAG_PARSE_SEMICOLON);
 555                 free(str);
 556                 rcode = last_return_code;
 557         }
 558         return rcode;
 559 }
 560
 561 /* built-in 'cd <path>' handler */
 562 static int builtin_cd(struct child_prog *child)
 563 {
 564         char *newdir;
 565         if (child->argv[1] == NULL)
 566                 newdir = getenv("HOME");
 567         else
 568                 newdir = child->argv[1];
 569         if (chdir(newdir)) {
 570                 printf("cd: %s: %s\n", newdir, strerror(errno));
 571                 return EXIT_FAILURE;
 572         }
 573         set_cwd();
 574         return EXIT_SUCCESS;
 575 }
 576
 577 /* built-in 'env' handler */
 578 static int builtin_env(struct child_prog *dummy)
 579 {
 580         char **e = environ;
 581         if (e == NULL) return EXIT_FAILURE;
 582         for (; *e; e++) {
 583                 puts(*e);
 584         }
 585         return EXIT_SUCCESS;
 586 }
 587
 588 /* built-in 'exec' handler */
 589 static int builtin_exec(struct child_prog *child)
 590 {
 591         if (child->argv[1] == NULL)
 592                 return EXIT_SUCCESS;   /* Really? */
 593         child->argv++;
 594         pseudo_exec(child);
 595         /* never returns */
 596 }
 597
 598 /* built-in 'exit' handler */
 599 static int builtin_exit(struct child_prog *child)
 600 {
 601         if (child->argv[1] == NULL)
 602                 exit(last_return_code);
 603         exit (atoi(child->argv[1]));
 604 }
 605
 606 /* built-in 'export VAR=value' handler */
 607 static int builtin_export(struct child_prog *child)
 608 {
 609         int res = 0;
 610         char *name = child->argv[1];
 611
 612         if (name == NULL) {
 613                 return (builtin_env(child));
 614         }
 615
 616         name = strdup(name);
 617
 618         if(name) {
 619                 char *value = strchr(name, '=');
 620
 621                 if (!value) {
 622                         char *tmp;
 623                         /* They are exporting something without an =VALUE */
 624
 625                         value = get_local_var(name);
 626                         if (value) {
 627                                 size_t ln = strlen(name);
 628
 629                                 tmp = realloc(name, ln+strlen(value)+2);
 630                                 if(tmp==NULL)
 631                                         res = -1;
 632                                 else {
 633                                         sprintf(tmp+ln, "=%s", value);
 634                                         name = tmp;
 635                                 }
 636                         } else {
 637                                 /* bash does not return an error when trying to export
 638                                  * an undefined variable.  Do likewise. */
 639                                 res = 1;
 640                         }
 641                 }
 642         }
 643         if (res<0)
 644                 perror_msg("export");
 645         else if(res==0)
 646                 res = set_local_var(name, 1);
 647         else
 648                 res = 0;
 649         free(name);
 650         return res;
 651 }
 652
 653 /* built-in 'fg' and 'bg' handler */
 654 static int builtin_fg_bg(struct child_prog *child)
 655 {
 656         int i, jobnum;
 657         struct pipe *pi=NULL;
 658
 659         if (!interactive)
 660                 return EXIT_FAILURE;
 661         /* If they gave us no args, assume they want the last backgrounded task */
 662         if (!child->argv[1]) {
 663                 for (pi = job_list; pi; pi = pi->next) {
 664                         if (pi->jobid == last_jobid) {
 665                                 break;
 666                         }
 667                 }
 668                 if (!pi) {
 669                         error_msg("%s: no current job", child->argv[0]);
 670                         return EXIT_FAILURE;
 671                 }
 672         } else {
 673                 if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
 674                         error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
 675                         return EXIT_FAILURE;
 676                 }
 677                 for (pi = job_list; pi; pi = pi->next) {
 678                         if (pi->jobid == jobnum) {
 679                                 break;
 680                         }
 681                 }
 682                 if (!pi) {
 683                         error_msg("%s: %d: no such job", child->argv[0], jobnum);
 684                         return EXIT_FAILURE;
 685                 }
 686         }
 687
 688         if (*child->argv[0] == 'f') {
 689                 /* Put the job into the foreground.  */
 690                 tcsetpgrp(shell_terminal, pi->pgrp);
 691         }
 692
 693         /* Restart the processes in the job */
 694         for (i = 0; i < pi->num_progs; i++)
 695                 pi->progs[i].is_stopped = 0;
 696
 697         if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) {
 698                 if (i == ESRCH) {
 699                         remove_bg_job(pi);
 700                 } else {
 701                         perror_msg("kill (SIGCONT)");
 702                 }
 703         }
 704
 705         pi->stopped_progs = 0;
 706         return EXIT_SUCCESS;
 707 }
 708
 709 /* built-in 'help' handler */
 710 static int builtin_help(struct child_prog *dummy)
 711 {
 712         struct built_in_command *x;
 713
 714         printf("\nBuilt-in commands:\n");
 715         printf("-------------------\n");
 716         for (x = bltins; x->cmd; x++) {
 717                 if (x->descr==NULL)
 718                         continue;
 719                 printf("%s\t%s\n", x->cmd, x->descr);
 720         }
 721         printf("\n\n");
 722         return EXIT_SUCCESS;
 723 }
 724
 725 /* built-in 'jobs' handler */
 726 static int builtin_jobs(struct child_prog *child)
 727 {
 728         struct pipe *job;
 729         char *status_string;
 730
 731         for (job = job_list; job; job = job->next) {
 732                 if (job->running_progs == job->stopped_progs)
 733                         status_string = "Stopped";
 734                 else
 735                         status_string = "Running";
 736
 737                 printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
 738         }
 739         return EXIT_SUCCESS;
 740 }
 741
 742
 743 /* built-in 'pwd' handler */
 744 static int builtin_pwd(struct child_prog *dummy)
 745 {
 746         puts(set_cwd());
 747         return EXIT_SUCCESS;
 748 }
 749
 750 /* built-in 'read VAR' handler */
 751 static int builtin_read(struct child_prog *child)
 752 {
 753         int res;
 754
 755         if (child->argv[1]) {
 756                 char string[BUFSIZ];
 757                 char *var = 0;
 758
 759                 string[0] = 0;  /* In case stdin has only EOF */
 760                 /* read string */
 761                 fgets(string, sizeof(string), stdin);
 762                 chomp(string);
 763                 var = malloc(strlen(child->argv[1])+strlen(string)+2);
 764                 if(var) {
 765                         sprintf(var, "%s=%s", child->argv[1], string);
 766                         res = set_local_var(var, 0);
 767                 } else
 768                         res = -1;
 769                 if (res)
 770                         fprintf(stderr, "read: %m\n");
 771                 free(var);      /* So not move up to avoid breaking errno */
 772                 return res;
 773         } else {
 774                 do res=getchar(); while(res!='\n' && res!=EOF);
 775                 return 0;
 776         }
 777 }
 778
 779 /* built-in 'set VAR=value' handler */
 780 static int builtin_set(struct child_prog *child)
 781 {
 782         char *temp = child->argv[1];
 783         struct variables *e;
 784
 785         if (temp == NULL)
 786                 for(e = top_vars; e; e=e->next)
 787                         printf("%s=%s\n", e->name, e->value);
 788         else
 789                 set_local_var(temp, 0);
 790
 791                 return EXIT_SUCCESS;
 792 }
 793
 794
 795 /* Built-in 'shift' handler */
 796 static int builtin_shift(struct child_prog *child)
 797 {
 798         int n=1;
 799         if (child->argv[1]) {
 800                 n=atoi(child->argv[1]);
 801         }
 802         if (n>=0 && n<global_argc) {
 803                 /* XXX This probably breaks $0 */
 804                 global_argc -= n;
 805                 global_argv += n;
 806                 return EXIT_SUCCESS;
 807         } else {
 808                 return EXIT_FAILURE;
 809         }
 810 }
 811
 812 /* Built-in '.' handler (read-in and execute commands from file) */
 813 static int builtin_source(struct child_prog *child)
 814 {
 815         FILE *input;
 816         int status;
 817
 818         if (child->argv[1] == NULL)
 819                 return EXIT_FAILURE;
 820
 821         /* XXX search through $PATH is missing */
 822         input = fopen(child->argv[1], "r");
 823         if (!input) {
 824                 error_msg("Couldn't open file '%s'", child->argv[1]);
 825                 return EXIT_FAILURE;
 826         }
 827
 828         /* Now run the file */
 829         /* XXX argv and argc are broken; need to save old global_argv
 830          * (pointer only is OK!) on this stack frame,
 831          * set global_argv=child->argv+1, recurse, and restore. */
 832         mark_open(fileno(input));
 833         status = parse_file_outer(input);
 834         mark_closed(fileno(input));
 835         fclose(input);
 836         return (status);
 837 }
 838
 839 static int builtin_umask(struct child_prog *child)
 840 {
 841         mode_t new_umask;
 842         const char *arg = child->argv[1];
 843         char *end;
 844         if (arg) {
 845                 new_umask=strtoul(arg, &end, 8);
 846                 if (*end!='\0' || end == arg) {
 847                         return EXIT_FAILURE;
 848                 }
 849         } else {
 850                 printf("%.3o\n", (unsigned int) (new_umask=umask(0)));
 851         }
 852         umask(new_umask);
 853         return EXIT_SUCCESS;
 854 }
 855
 856 /* built-in 'unset VAR' handler */
 857 static int builtin_unset(struct child_prog *child)
 858 {
 859         /* bash returned already true */
 860         unset_local_var(child->argv[1]);
 861         return EXIT_SUCCESS;
 862 }
 863
 864 static int builtin_not_written(struct child_prog *child)
 865 {
 866         printf("builtin_%s not written\n",child->argv[0]);
 867         return EXIT_FAILURE;
 868 }
 869 #endif
 870
 871 static int b_check_space(o_string *o, int len)
 872 {
 873         /* It would be easy to drop a more restrictive policy
 874          * in here, such as setting a maximum string length */
 875         if (o->length + len > o->maxlen) {
 876                 char *old_data = o->data;
 877                 /* assert (data == NULL || o->maxlen != 0); */
 878                 o->maxlen += max(2*len, B_CHUNK);
 879                 o->data = realloc(o->data, 1 + o->maxlen);
 880                 if (o->data == NULL) {
 881                         free(old_data);
 882                 }
 883         }
 884         return o->data == NULL;
 885 }
 886
 887 static int b_addchr(o_string *o, int ch)
 888 {
 889         debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
 890         if (b_check_space(o, 1)) return B_NOSPAC;
 891         o->data[o->length] = ch;
 892         o->length++;
 893         o->data[o->length] = '\0';
 894         return 0;
 895 }
 896
 897 static void b_reset(o_string *o)
 898 {
 899         o->length = 0;
 900         o->nonnull = 0;
 901         if (o->data != NULL) *o->data = '\0';
 902 }
 903
 904 static void b_free(o_string *o)
 905 {
 906         b_reset(o);
 907         free(o->data);
 908         o->data = NULL;
 909         o->maxlen = 0;
 910 }
 911
 912 /* My analysis of quoting semantics tells me that state information
 913  * is associated with a destination, not a source.
 914  */
 915 static int b_addqchr(o_string *o, int ch, int quote)
 916 {
 917         if (quote && strchr("*?[\\",ch)) {
 918                 int rc;
 919                 rc = b_addchr(o, '\\');
 920                 if (rc) return rc;
 921         }
 922         return b_addchr(o, ch);
 923 }
 924
 925 /* belongs in utility.c */
 926 char *simple_itoa(unsigned int i)
 927 {
 928         /* 21 digits plus null terminator, good for 64-bit or smaller ints */
 929         static char local[22];
 930         char *p = &local[21];
 931         *p-- = '\0';
 932         do {
 933                 *p-- = '0' + i % 10;
 934                 i /= 10;
 935         } while (i > 0);
 936         return p + 1;
 937 }
 938
 939 static int b_adduint(o_string *o, unsigned int i)
 940 {
 941         int r;
 942         char *p = simple_itoa(i);
 943         /* no escape checking necessary */
 944         do r=b_addchr(o, *p++); while (r==0 && *p);
 945         return r;
 946 }
 947
 948 static int static_get(struct in_str *i)
 949 {
 950         int ch=*i->p++;
 951         if (ch=='\0') return EOF;
 952         return ch;
 953 }
 954
 955 static int static_peek(struct in_str *i)
 956 {
 957         return *i->p;
 958 }
 959
 960 #ifndef __U_BOOT__
 961 static inline void cmdedit_set_initial_prompt(void)
 962 {
 963 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
 964         PS1 = NULL;
 965 #else
 966         PS1 = getenv("PS1");
 967         if(PS1==0)
 968                 PS1 = "\\w \\$ ";
 969 #endif
 970 }
 971
 972 static inline void setup_prompt_string(int promptmode, char **prompt_str)
 973 {
 974         debug_printf("setup_prompt_string %d ",promptmode);
 975 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
 976         /* Set up the prompt */
 977         if (promptmode == 1) {
 978                 free(PS1);
 979                 PS1=xmalloc(strlen(cwd)+4);
 980                 sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ?  "$ ":"# ");
 981                 *prompt_str = PS1;
 982         } else {
 983                 *prompt_str = PS2;
 984         }
 985 #else
 986         *prompt_str = (promptmode==1)? PS1 : PS2;
 987 #endif
 988         debug_printf("result %s\n",*prompt_str);
 989 }
 990 #endif
 991
 992 static void get_user_input(struct in_str *i)
 993 {
 994 #ifndef __U_BOOT__
 995         char *prompt_str;
 996         static char the_command[BUFSIZ];
 997
 998         setup_prompt_string(i->promptmode, &prompt_str);
 999 #ifdef CONFIG_FEATURE_COMMAND_EDITING
1000         /*
1001          ** enable command line editing only while a command line
1002          ** is actually being read; otherwise, we'll end up bequeathing
1003          ** atexit() handlers and other unwanted stuff to our
1004          ** child processes (rob@sysgo.de)
1005          */
1006         cmdedit_read_input(prompt_str, the_command);
1007 #else
1008         fputs(prompt_str, stdout);
1009         fflush(stdout);
1010         the_command[0]=fgetc(i->file);
1011         the_command[1]='\0';
1012 #endif
1013         fflush(stdout);
1014         i->p = the_command;
1015 #else
1016         extern char console_buffer[CFG_CBSIZE];
1017         int n;
1018         static char the_command[CFG_CBSIZE];
1019
1020         i->__promptme = 1;
1021         if (i->promptmode == 1) {
1022                 n = readline(CFG_PROMPT);
1023         } else {
1024                 n = readline(CFG_PROMPT_HUSH_PS2);
1025         }
1026         if (n == -1 ) {
1027                 flag_repeat = 0;
1028                 i->__promptme = 0;
1029         }
1030         n = strlen(console_buffer);
1031         console_buffer[n] = '\n';
1032         console_buffer[n+1]= '\0';
1033         if (had_ctrlc()) flag_repeat = 0;
1034         clear_ctrlc();
1035         do_repeat = 0;
1036         if (i->promptmode == 1) {
1037                 if (console_buffer[0] == '\n'&& flag_repeat == 0) {
1038                         strcpy(the_command,console_buffer);
1039                 }
1040                 else {
1041                         if (console_buffer[0] != '\n') {
1042                                 strcpy(the_command,console_buffer);
1043                                 flag_repeat = 1;
1044                         }
1045                         else {
1046                                 do_repeat = 1;
1047                         }
1048                 }
1049                 i->p = the_command;
1050         }
1051         else {
1052                 if (console_buffer[0] != '\n') {
1053                         if (strlen(the_command) + strlen(console_buffer)
1054                             < CFG_CBSIZE) {
1055                                 n = strlen(the_command);
1056                                 the_command[n-1] = ' ';
1057                                 strcpy(&the_command[n],console_buffer);
1058                         }
1059                         else {
1060                                 the_command[0] = '\n';
1061                                 the_command[1] = '\0';
1062                                 flag_repeat = 0;
1063                         }
1064                 }
1065                 if (i->__promptme == 0) {
1066                         the_command[0] = '\n';
1067                         the_command[1] = '\0';
1068                 }
1069                 i->p = console_buffer;
1070         }
1071 #endif
1072 }
1073
1074 /* This is the magic location that prints prompts
1075  * and gets data back from the user */
1076 static int file_get(struct in_str *i)
1077 {
1078         int ch;
1079
1080         ch = 0;
1081         /* If there is data waiting, eat it up */
1082         if (i->p && *i->p) {
1083                 ch=*i->p++;
1084         } else {
1085                 /* need to double check i->file because we might be doing something
1086                  * more complicated by now, like sourcing or substituting. */
1087 #ifndef __U_BOOT__
1088                 if (i->__promptme && interactive && i->file == stdin) {
1089                         while(! i->p || (interactive && strlen(i->p)==0) ) {
1090 #else
1091                         while(! i->p  || strlen(i->p)==0 ) {
1092 #endif
1093                                 get_user_input(i);
1094                         }
1095                         i->promptmode=2;
1096 #ifndef __U_BOOT__
1097                         i->__promptme = 0;
1098 #endif
1099                         if (i->p && *i->p) {
1100                                 ch=*i->p++;
1101                         }
1102 #ifndef __U_BOOT__
1103                 } else {
1104                         ch = fgetc(i->file);
1105                 }
1106
1107 #endif
1108                 debug_printf("b_getch: got a %d\n", ch);
1109         }
1110 #ifndef __U_BOOT__
1111         if (ch == '\n') i->__promptme=1;
1112 #endif
1113         return ch;
1114 }
1115
1116 /* All the callers guarantee this routine will never be
1117  * used right after a newline, so prompting is not needed.
1118  */
1119 static int file_peek(struct in_str *i)
1120 {
1121 #ifndef __U_BOOT__
1122         if (i->p && *i->p) {
1123 #endif
1124                 return *i->p;
1125 #ifndef __U_BOOT__
1126         } else {
1127                 i->peek_buf[0] = fgetc(i->file);
1128                 i->peek_buf[1] = '\0';
1129                 i->p = i->peek_buf;
1130                 debug_printf("b_peek: got a %d\n", *i->p);
1131                 return *i->p;
1132         }
1133 #endif
1134 }
1135
1136 #ifndef __U_BOOT__
1137 static void setup_file_in_str(struct in_str *i, FILE *f)
1138 #else
1139 static void setup_file_in_str(struct in_str *i)
1140 #endif
1141 {
1142         i->peek = file_peek;
1143         i->get = file_get;
1144         i->__promptme=1;
1145         i->promptmode=1;
1146 #ifndef __U_BOOT__
1147         i->file = f;
1148 #endif
1149         i->p = NULL;
1150 }
1151
1152 static void setup_string_in_str(struct in_str *i, const char *s)
1153 {
1154         i->peek = static_peek;
1155         i->get = static_get;
1156         i->__promptme=1;
1157         i->promptmode=1;
1158         i->p = s;
1159 }
1160
1161 #ifndef __U_BOOT__
1162 static void mark_open(int fd)
1163 {
1164         struct close_me *new = xmalloc(sizeof(struct close_me));
1165         new->fd = fd;
1166         new->next = close_me_head;
1167         close_me_head = new;
1168 }
1169
1170 static void mark_closed(int fd)
1171 {
1172         struct close_me *tmp;
1173         if (close_me_head == NULL || close_me_head->fd != fd)
1174                 error_msg_and_die("corrupt close_me");
1175         tmp = close_me_head;
1176         close_me_head = close_me_head->next;
1177         free(tmp);
1178 }
1179
1180 static void close_all(void)
1181 {
1182         struct close_me *c;
1183         for (c=close_me_head; c; c=c->next) {
1184                 close(c->fd);
1185         }
1186         close_me_head = NULL;
1187 }
1188
1189 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1190  * and stderr if they are redirected. */
1191 static int setup_redirects(struct child_prog *prog, int squirrel[])
1192 {
1193         int openfd, mode;
1194         struct redir_struct *redir;
1195
1196         for (redir=prog->redirects; redir; redir=redir->next) {
1197                 if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1198                         /* something went wrong in the parse.  Pretend it didn't happen */
1199                         continue;
1200                 }
1201                 if (redir->dup == -1) {
1202                         mode=redir_table[redir->type].mode;
1203                         openfd = open(redir->word.gl_pathv[0], mode, 0666);
1204                         if (openfd < 0) {
1205                         /* this could get lost if stderr has been redirected, but
1206                            bash and ash both lose it as well (though zsh doesn't!) */
1207                                 perror_msg("error opening %s", redir->word.gl_pathv[0]);
1208                                 return 1;
1209                         }
1210                 } else {
1211                         openfd = redir->dup;
1212                 }
1213
1214                 if (openfd != redir->fd) {
1215                         if (squirrel && redir->fd < 3) {
1216                                 squirrel[redir->fd] = dup(redir->fd);
1217                         }
1218                         if (openfd == -3) {
1219                                 close(openfd);
1220                         } else {
1221                                 dup2(openfd, redir->fd);
1222                                 if (redir->dup == -1)
1223                                         close (openfd);
1224                         }
1225                 }
1226         }
1227         return 0;
1228 }
1229
1230 static void restore_redirects(int squirrel[])
1231 {
1232         int i, fd;
1233         for (i=0; i<3; i++) {
1234                 fd = squirrel[i];
1235                 if (fd != -1) {
1236                         /* No error checking.  I sure wouldn't know what
1237                          * to do with an error if I found one! */
1238                         dup2(fd, i);
1239                         close(fd);
1240                 }
1241         }
1242 }
1243
1244 /* never returns */
1245 /* XXX no exit() here.  If you don't exec, use _exit instead.
1246  * The at_exit handlers apparently confuse the calling process,
1247  * in particular stdin handling.  Not sure why? */
1248 static void pseudo_exec(struct child_prog *child)
1249 {
1250         int i, rcode;
1251         char *p;
1252         struct built_in_command *x;
1253         if (child->argv) {
1254                 for (i=0; is_assignment(child->argv[i]); i++) {
1255                         debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
1256                         p = insert_var_value(child->argv[i]);
1257                         putenv(strdup(p));
1258                         if (p != child->argv[i]) free(p);
1259                 }
1260                 child->argv+=i;  /* XXX this hack isn't so horrible, since we are about
1261                                         to exit, and therefore don't need to keep data
1262                                         structures consistent for free() use. */
1263                 /* If a variable is assigned in a forest, and nobody listens,
1264                  * was it ever really set?
1265                  */
1266                 if (child->argv[0] == NULL) {
1267                         _exit(EXIT_SUCCESS);
1268                 }
1269
1270                 /*
1271                  * Check if the command matches any of the builtins.
1272                  * Depending on context, this might be redundant.  But it's
1273                  * easier to waste a few CPU cycles than it is to figure out
1274                  * if this is one of those cases.
1275                  */
1276                 for (x = bltins; x->cmd; x++) {
1277                         if (strcmp(child->argv[0], x->cmd) == 0 ) {
1278                                 debug_printf("builtin exec %s\n", child->argv[0]);
1279                                 rcode = x->function(child);
1280                                 fflush(stdout);
1281                                 _exit(rcode);
1282                         }
1283                 }
1284
1285                 /* Check if the command matches any busybox internal commands
1286                  * ("applets") here.
1287                  * FIXME: This feature is not 100% safe, since
1288                  * BusyBox is not fully reentrant, so we have no guarantee the things
1289                  * from the .bss are still zeroed, or that things from .data are still
1290                  * at their defaults.  We could exec ourself from /proc/self/exe, but I
1291                  * really dislike relying on /proc for things.  We could exec ourself
1292                  * from global_argv[0], but if we are in a chroot, we may not be able
1293                  * to find ourself... */
1294 #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1295                 {
1296                         int argc_l;
1297                         char** argv_l=child->argv;
1298                         char *name = child->argv[0];
1299
1300 #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
1301                         /* Following discussions from November 2000 on the busybox mailing
1302                          * list, the default configuration, (without
1303                          * get_last_path_component()) lets the user force use of an
1304                          * external command by specifying the full (with slashes) filename.
1305                          * If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN then applets
1306                          * _aways_ override external commands, so if you want to run
1307                          * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the
1308                          * filesystem and is _not_ busybox.  Some systems may want this,
1309                          * most do not.  */
1310                         name = get_last_path_component(name);
1311 #endif
1312                         /* Count argc for use in a second... */
1313                         for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
1314                         optind = 1;
1315                         debug_printf("running applet %s\n", name);
1316                         run_applet_by_name(name, argc_l, child->argv);
1317                 }
1318 #endif
1319                 debug_printf("exec of %s\n",child->argv[0]);
1320                 execvp(child->argv[0],child->argv);
1321                 perror_msg("couldn't exec: %s",child->argv[0]);
1322                 _exit(1);
1323         } else if (child->group) {
1324                 debug_printf("runtime nesting to group\n");
1325                 interactive=0;    /* crucial!!!! */
1326                 rcode = run_list_real(child->group);
1327                 /* OK to leak memory by not calling free_pipe_list,
1328                  * since this process is about to exit */
1329                 _exit(rcode);
1330         } else {
1331                 /* Can happen.  See what bash does with ">foo" by itself. */
1332                 debug_printf("trying to pseudo_exec null command\n");
1333                 _exit(EXIT_SUCCESS);
1334         }
1335 }
1336
1337 static void insert_bg_job(struct pipe *pi)
1338 {
1339         struct pipe *thejob;
1340
1341         /* Linear search for the ID of the job to use */
1342         pi->jobid = 1;
1343         for (thejob = job_list; thejob; thejob = thejob->next)
1344                 if (thejob->jobid >= pi->jobid)
1345                         pi->jobid = thejob->jobid + 1;
1346
1347         /* add thejob to the list of running jobs */
1348         if (!job_list) {
1349                 thejob = job_list = xmalloc(sizeof(*thejob));
1350         } else {
1351                 for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
1352                 thejob->next = xmalloc(sizeof(*thejob));
1353                 thejob = thejob->next;
1354         }
1355
1356         /* physically copy the struct job */
1357         memcpy(thejob, pi, sizeof(struct pipe));
1358         thejob->next = NULL;
1359         thejob->running_progs = thejob->num_progs;
1360         thejob->stopped_progs = 0;
1361         thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1362
1363         /*if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) */
1364         {
1365                 char *bar=thejob->text;
1366                 char **foo=pi->progs[0].argv;
1367                 while(foo && *foo) {
1368                         bar += sprintf(bar, "%s ", *foo++);
1369                 }
1370         }
1371
1372         /* we don't wait for background thejobs to return -- append it
1373            to the list of backgrounded thejobs and leave it alone */
1374         printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1375         last_bg_pid = thejob->progs[0].pid;
1376         last_jobid = thejob->jobid;
1377 }
1378
1379 /* remove a backgrounded job */
1380 static void remove_bg_job(struct pipe *pi)
1381 {
1382         struct pipe *prev_pipe;
1383
1384         if (pi == job_list) {
1385                 job_list = pi->next;
1386         } else {
1387                 prev_pipe = job_list;
1388                 while (prev_pipe->next != pi)
1389                         prev_pipe = prev_pipe->next;
1390                 prev_pipe->next = pi->next;
1391         }
1392         if (job_list)
1393                 last_jobid = job_list->jobid;
1394         else
1395                 last_jobid = 0;
1396
1397         pi->stopped_progs = 0;
1398         free_pipe(pi, 0);
1399         free(pi);
1400 }
1401
1402 /* Checks to see if any processes have exited -- if they
1403    have, figure out why and see if a job has completed */
1404 static int checkjobs(struct pipe* fg_pipe)
1405 {
1406         int attributes;
1407         int status;
1408         int prognum = 0;
1409         struct pipe *pi;
1410         pid_t childpid;
1411
1412         attributes = WUNTRACED;
1413         if (fg_pipe==NULL) {
1414                 attributes |= WNOHANG;
1415         }
1416
1417         while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1418                 if (fg_pipe) {
1419                         int i, rcode = 0;
1420                         for (i=0; i < fg_pipe->num_progs; i++) {
1421                                 if (fg_pipe->progs[i].pid == childpid) {
1422                                         if (i==fg_pipe->num_progs-1)
1423                                                 rcode=WEXITSTATUS(status);
1424                                         (fg_pipe->num_progs)--;
1425                                         return(rcode);
1426                                 }
1427                         }
1428                 }
1429
1430                 for (pi = job_list; pi; pi = pi->next) {
1431                         prognum = 0;
1432                         while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1433                                 prognum++;
1434                         }
1435                         if (prognum < pi->num_progs)
1436                                 break;
1437                 }
1438
1439                 if(pi==NULL) {
1440                         debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
1441                         continue;
1442                 }
1443
1444                 if (WIFEXITED(status) || WIFSIGNALED(status)) {
1445                         /* child exited */
1446                         pi->running_progs--;
1447                         pi->progs[prognum].pid = 0;
1448
1449                         if (!pi->running_progs) {
1450                                 printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
1451                                 remove_bg_job(pi);
1452                         }
1453                 } else {
1454                         /* child stopped */
1455                         pi->stopped_progs++;
1456                         pi->progs[prognum].is_stopped = 1;
1457
1458 #if 0
1459                         /* Printing this stuff is a pain, since it tends to
1460                          * overwrite the prompt an inconveinient moments.  So
1461                          * don't do that.  */
1462                         if (pi->stopped_progs == pi->num_progs) {
1463                                 printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
1464                         }
1465 #endif
1466                 }
1467         }
1468
1469         if (childpid == -1 && errno != ECHILD)
1470                 perror_msg("waitpid");
1471
1472         /* move the shell to the foreground */
1473         /*if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) */
1474         /*      perror_msg("tcsetpgrp-2"); */
1475         return -1;
1476 }
1477
1478 /* Figure out our controlling tty, checking in order stderr,
1479  * stdin, and stdout.  If check_pgrp is set, also check that
1480  * we belong to the foreground process group associated with
1481  * that tty.  The value of shell_terminal is needed in order to call
1482  * tcsetpgrp(shell_terminal, ...); */
1483 void controlling_tty(int check_pgrp)
1484 {
1485         pid_t curpgrp;
1486
1487         if ((curpgrp = tcgetpgrp(shell_terminal = 2)) < 0
1488                         && (curpgrp = tcgetpgrp(shell_terminal = 0)) < 0
1489                         && (curpgrp = tcgetpgrp(shell_terminal = 1)) < 0)
1490                 goto shell_terminal_error;
1491
1492         if (check_pgrp && curpgrp != getpgid(0))
1493                 goto shell_terminal_error;
1494
1495         return;
1496
1497 shell_terminal_error:
1498                 shell_terminal = -1;
1499                 return;
1500 }
1501 #endif
1502
1503 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1504  * to finish.  See checkjobs().
1505  *
1506  * return code is normally -1, when the caller has to wait for children
1507  * to finish to determine the exit status of the pipe.  If the pipe
1508  * is a simple builtin command, however, the action is done by the
1509  * time run_pipe_real returns, and the exit code is provided as the
1510  * return value.
1511  *
1512  * The input of the pipe is always stdin, the output is always
1513  * stdout.  The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1514  * because it tries to avoid running the command substitution in
1515  * subshell, when that is in fact necessary.  The subshell process
1516  * now has its stdout directed to the input of the appropriate pipe,
1517  * so this routine is noticeably simpler.
1518  */
1519 static int run_pipe_real(struct pipe *pi)
1520 {
1521         int i;
1522 #ifndef __U_BOOT__
1523         int nextin, nextout;
1524         int pipefds[2];                         /* pipefds[0] is for reading */
1525         struct child_prog *child;
1526         struct built_in_command *x;
1527         char *p;
1528 # if __GNUC__
1529         /* Avoid longjmp clobbering */
1530         (void) &i;
1531         (void) &nextin;
1532         (void) &nextout;
1533         (void) &child;
1534 # endif
1535 #else
1536         int nextin;
1537         int flag = do_repeat ? CMD_FLAG_REPEAT : 0;
1538         struct child_prog *child;
1539         cmd_tbl_t *cmdtp;
1540         char *p;
1541 # if __GNUC__
1542         /* Avoid longjmp clobbering */
1543         (void) &i;
1544         (void) &nextin;
1545         (void) &child;
1546 # endif
1547 #endif  /* __U_BOOT__ */
1548
1549         nextin = 0;
1550 #ifndef __U_BOOT__
1551         pi->pgrp = -1;
1552 #endif
1553
1554         /* Check if this is a simple builtin (not part of a pipe).
1555          * Builtins within pipes have to fork anyway, and are handled in
1556          * pseudo_exec.  "echo foo | read bar" doesn't work on bash, either.
1557          */
1558         if (pi->num_progs == 1) child = & (pi->progs[0]);
1559 #ifndef __U_BOOT__
1560         if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1561                 int squirrel[] = {-1, -1, -1};
1562                 int rcode;
1563                 debug_printf("non-subshell grouping\n");
1564                 setup_redirects(child, squirrel);
1565                 /* XXX could we merge code with following builtin case,
1566                  * by creating a pseudo builtin that calls run_list_real? */
1567                 rcode = run_list_real(child->group);
1568                 restore_redirects(squirrel);
1569 #else
1570                 if (pi->num_progs == 1 && child->group) {
1571                 int rcode;
1572                 debug_printf("non-subshell grouping\n");
1573                 rcode = run_list_real(child->group);
1574 #endif
1575                 return rcode;
1576         } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1577                 for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
1578                 if (i!=0 && child->argv[i]==NULL) {
1579                         /* assignments, but no command: set the local environment */
1580                         for (i=0; child->argv[i]!=NULL; i++) {
1581
1582                                 /* Ok, this case is tricky.  We have to decide if this is a
1583                                  * local variable, or an already exported variable.  If it is
1584                                  * already exported, we have to export the new value.  If it is
1585                                  * not exported, we need only set this as a local variable.
1586                                  * This junk is all to decide whether or not to export this
1587                                  * variable. */
1588                                 int export_me=0;
1589                                 char *name, *value;
1590                                 name = xstrdup(child->argv[i]);
1591                                 debug_printf("Local environment set: %s\n", name);
1592                                 value = strchr(name, '=');
1593                                 if (value)
1594                                         *value=0;
1595 #ifndef __U_BOOT__
1596                                 if ( get_local_var(name)) {
1597                                         export_me=1;
1598                                 }
1599 #endif
1600                                 free(name);
1601                                 p = insert_var_value(child->argv[i]);
1602                                 set_local_var(p, export_me);
1603                                 if (p != child->argv[i]) free(p);
1604                         }
1605                         return EXIT_SUCCESS;   /* don't worry about errors in set_local_var() yet */
1606                 }
1607                 for (i = 0; is_assignment(child->argv[i]); i++) {
1608                         p = insert_var_value(child->argv[i]);
1609 #ifndef __U_BOOT__
1610                         putenv(strdup(p));
1611 #else
1612                         set_local_var(p, 0);
1613 #endif
1614                         if (p != child->argv[i]) {
1615                                 child->sp--;
1616                                 free(p);
1617                         }
1618                 }
1619                 if (child->sp) {
1620                         char * str = NULL;
1621
1622                         str = make_string((child->argv + i));
1623                         parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1624                         free(str);
1625                         return last_return_code;
1626                 }
1627 #ifndef __U_BOOT__
1628                 for (x = bltins; x->cmd; x++) {
1629                         if (strcmp(child->argv[i], x->cmd) == 0 ) {
1630                                 int squirrel[] = {-1, -1, -1};
1631                                 int rcode;
1632                                 if (x->function == builtin_exec && child->argv[i+1]==NULL) {
1633                                         debug_printf("magic exec\n");
1634                                         setup_redirects(child,NULL);
1635                                         return EXIT_SUCCESS;
1636                                 }
1637                                 debug_printf("builtin inline %s\n", child->argv[0]);
1638                                 /* XXX setup_redirects acts on file descriptors, not FILEs.
1639                                  * This is perfect for work that comes after exec().
1640                                  * Is it really safe for inline use?  Experimentally,
1641                                  * things seem to work with glibc. */
1642                                 setup_redirects(child, squirrel);
1643 #else
1644                         /* check ";", because ,example , argv consist from
1645                          * "help;flinfo" must not execute
1646                          */
1647                         if (strchr(child->argv[i], ';')) {
1648                                 printf ("Unknown command '%s' - try 'help' or use 'run' command\n",
1649                                         child->argv[i]);
1650                                 return -1;
1651                         }
1652                         /* Look up command in command table */
1653
1654
1655                         if ((cmdtp = find_cmd(child->argv[i])) == NULL) {
1656                                 printf ("Unknown command '%s' - try 'help'\n", child->argv[i]);
1657                                 return -1;      /* give up after bad command */
1658                         } else {
1659                                 int rcode;
1660 #if (CONFIG_COMMANDS & CFG_CMD_BOOTD)
1661             extern int do_bootd (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]);
1662
1663                                 /* avoid "bootd" recursion */
1664                                 if (cmdtp->cmd == do_bootd) {
1665                                         if (flag & CMD_FLAG_BOOTD) {
1666                                                 printf ("'bootd' recursion detected\n");
1667                                                 return -1;
1668                                         }
1669                                 else
1670                                         flag |= CMD_FLAG_BOOTD;
1671                                 }
1672 #endif  /* CFG_CMD_BOOTD */
1673                                 /* found - check max args */
1674                                 if ((child->argc - i) > cmdtp->maxargs) {
1675                                         printf ("Usage:\n%s\n", cmdtp->usage);
1676                                         return -1;
1677                                 }
1678 #endif
1679                                 child->argv+=i;  /* XXX horrible hack */
1680 #ifndef __U_BOOT__
1681                                 rcode = x->function(child);
1682 #else
1683                                 /* OK - call function to do the command */
1684
1685                                 rcode = (cmdtp->cmd)
1686 (cmdtp, flag,child->argc-i,&child->argv[i]);
1687                                 if ( !cmdtp->repeatable )
1688                                         flag_repeat = 0;
1689
1690
1691 #endif
1692                                 child->argv-=i;  /* XXX restore hack so free() can work right */
1693 #ifndef __U_BOOT__
1694
1695                                 restore_redirects(squirrel);
1696 #endif
1697
1698                                 return rcode;
1699                         }
1700                 }
1701 #ifndef __U_BOOT__
1702         }
1703
1704         for (i = 0; i < pi->num_progs; i++) {
1705                 child = & (pi->progs[i]);
1706
1707                 /* pipes are inserted between pairs of commands */
1708                 if ((i + 1) < pi->num_progs) {
1709                         if (pipe(pipefds)<0) perror_msg_and_die("pipe");
1710                         nextout = pipefds[1];
1711                 } else {
1712                         nextout=1;
1713                         pipefds[0] = -1;
1714                 }
1715
1716                 /* XXX test for failed fork()? */
1717                 if (!(child->pid = fork())) {
1718                         /* Set the handling for job control signals back to the default.  */
1719                         signal(SIGINT, SIG_DFL);
1720                         signal(SIGQUIT, SIG_DFL);
1721                         signal(SIGTERM, SIG_DFL);
1722                         signal(SIGTSTP, SIG_DFL);
1723                         signal(SIGTTIN, SIG_DFL);
1724                         signal(SIGTTOU, SIG_DFL);
1725                         signal(SIGCHLD, SIG_DFL);
1726
1727                         close_all();
1728
1729                         if (nextin != 0) {
1730                                 dup2(nextin, 0);
1731                                 close(nextin);
1732                         }
1733                         if (nextout != 1) {
1734                                 dup2(nextout, 1);
1735                                 close(nextout);
1736                         }
1737                         if (pipefds[0]!=-1) {
1738                                 close(pipefds[0]);  /* opposite end of our output pipe */
1739                         }
1740
1741                         /* Like bash, explicit redirects override pipes,
1742                          * and the pipe fd is available for dup'ing. */
1743                         setup_redirects(child,NULL);
1744
1745                         if (interactive && pi->followup!=PIPE_BG) {
1746                                 /* If we (the child) win the race, put ourselves in the process
1747                                  * group whose leader is the first process in this pipe. */
1748                                 if (pi->pgrp < 0) {
1749                                         pi->pgrp = getpid();
1750                                 }
1751                                 if (setpgid(0, pi->pgrp) == 0) {
1752                                         tcsetpgrp(2, pi->pgrp);
1753                                 }
1754                         }
1755
1756                         pseudo_exec(child);
1757                 }
1758
1759
1760                 /* put our child in the process group whose leader is the
1761                    first process in this pipe */
1762                 if (pi->pgrp < 0) {
1763                         pi->pgrp = child->pid;
1764                 }
1765                 /* Don't check for errors.  The child may be dead already,
1766                  * in which case setpgid returns error code EACCES. */
1767                 setpgid(child->pid, pi->pgrp);
1768
1769                 if (nextin != 0)
1770                         close(nextin);
1771                 if (nextout != 1)
1772                         close(nextout);
1773
1774                 /* If there isn't another process, nextin is garbage
1775                    but it doesn't matter */
1776                 nextin = pipefds[0];
1777         }
1778 #endif
1779         return -1;
1780 }
1781
1782 static int run_list_real(struct pipe *pi)
1783 {
1784         char *save_name = NULL;
1785         char **list = NULL;
1786         char **save_list = NULL;
1787         struct pipe *rpipe;
1788         int flag_rep = 0;
1789 #ifndef __U_BOOT__
1790         int save_num_progs;
1791 #endif
1792         int rcode=0, flag_skip=1;
1793         int flag_restore = 0;
1794         int if_code=0, next_if_code=0;  /* need double-buffer to handle elif */
1795         reserved_style rmode, skip_more_in_this_rmode=RES_XXXX;
1796         /* check syntax for "for" */
1797         for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1798                 if ((rpipe->r_mode == RES_IN ||
1799                     rpipe->r_mode == RES_FOR) &&
1800                     (rpipe->next == NULL)) {
1801                                 syntax();
1802 #ifdef __U_BOOT__
1803                                 flag_repeat = 0;
1804 #endif
1805                                 return 1;
1806                 }
1807                 if ((rpipe->r_mode == RES_IN &&
1808                         (rpipe->next->r_mode == RES_IN &&
1809                         rpipe->next->progs->argv != NULL))||
1810                         (rpipe->r_mode == RES_FOR &&
1811                         rpipe->next->r_mode != RES_IN)) {
1812                                 syntax();
1813 #ifdef __U_BOOT__
1814                                 flag_repeat = 0;
1815 #endif
1816                                 return 1;
1817                 }
1818         }
1819         for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1820                 if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
1821                         pi->r_mode == RES_FOR) {
1822 #ifdef __U_BOOT__
1823                                 /* check Ctrl-C */
1824                                 ctrlc();
1825                                 if ((had_ctrlc())) {
1826                                         return 1;
1827                                 }
1828 #endif
1829                                 flag_restore = 0;
1830                                 if (!rpipe) {
1831                                         flag_rep = 0;
1832                                         rpipe = pi;
1833                                 }
1834                 }
1835                 rmode = pi->r_mode;
1836                 debug_printf("rmode=%d  if_code=%d  next_if_code=%d skip_more=%d\n", rmode, if_code, next_if_code, skip_more_in_this_rmode);
1837                 if (rmode == skip_more_in_this_rmode && flag_skip) {
1838                         if (pi->followup == PIPE_SEQ) flag_skip=0;
1839                         continue;
1840                 }
1841                 flag_skip = 1;
1842                 skip_more_in_this_rmode = RES_XXXX;
1843                 if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
1844                 if (rmode == RES_THEN &&  if_code) continue;
1845                 if (rmode == RES_ELSE && !if_code) continue;
1846                 if (rmode == RES_ELIF && !if_code) break;
1847                 if (rmode == RES_FOR && pi->num_progs) {
1848                         if (!list) {
1849                                 /* if no variable values after "in" we skip "for" */
1850                                 if (!pi->next->progs->argv) continue;
1851                                 /* create list of variable values */
1852                                 list = make_list_in(pi->next->progs->argv,
1853                                         pi->progs->argv[0]);
1854                                 save_list = list;
1855                                 save_name = pi->progs->argv[0];
1856                                 pi->progs->argv[0] = NULL;
1857                                 flag_rep = 1;
1858                         }
1859                         if (!(*list)) {
1860                                 free(pi->progs->argv[0]);
1861                                 free(save_list);
1862                                 list = NULL;
1863                                 flag_rep = 0;
1864                                 pi->progs->argv[0] = save_name;
1865 #ifndef __U_BOOT__
1866                                 pi->progs->glob_result.gl_pathv[0] =
1867                                         pi->progs->argv[0];
1868 #endif
1869                                 continue;
1870                         } else {
1871                                 /* insert new value from list for variable */
1872                                 if (pi->progs->argv[0])
1873                                         free(pi->progs->argv[0]);
1874                                 pi->progs->argv[0] = *list++;
1875 #ifndef __U_BOOT__
1876                                 pi->progs->glob_result.gl_pathv[0] =
1877                                         pi->progs->argv[0];
1878 #endif
1879                         }
1880                 }
1881                 if (rmode == RES_IN) continue;
1882                 if (rmode == RES_DO) {
1883                         if (!flag_rep) continue;
1884                 }
1885                 if ((rmode == RES_DONE)) {
1886                         if (flag_rep) {
1887                                 flag_restore = 1;
1888                         } else {
1889                                 rpipe = NULL;
1890                         }
1891                 }
1892                 if (pi->num_progs == 0) continue;
1893 #ifndef __U_BOOT__
1894                 save_num_progs = pi->num_progs; /* save number of programs */
1895 #endif
1896                 rcode = run_pipe_real(pi);
1897                 debug_printf("run_pipe_real returned %d\n",rcode);
1898 #ifndef __U_BOOT__
1899                 if (rcode!=-1) {
1900                         /* We only ran a builtin: rcode was set by the return value
1901                          * of run_pipe_real(), and we don't need to wait for anything. */
1902                 } else if (pi->followup==PIPE_BG) {
1903                         /* XXX check bash's behavior with nontrivial pipes */
1904                         /* XXX compute jobid */
1905                         /* XXX what does bash do with attempts to background builtins? */
1906                         insert_bg_job(pi);
1907                         rcode = EXIT_SUCCESS;
1908                 } else {
1909                         if (interactive) {
1910                                 /* move the new process group into the foreground */
1911                                 if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1912                                         perror_msg("tcsetpgrp-3");
1913                                 rcode = checkjobs(pi);
1914                                 /* move the shell to the foreground */
1915                                 if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1916                                         perror_msg("tcsetpgrp-4");
1917                         } else {
1918                                 rcode = checkjobs(pi);
1919                         }
1920                         debug_printf("checkjobs returned %d\n",rcode);
1921                 }
1922                 last_return_code=rcode;
1923 #else
1924                 last_return_code=(rcode == 0) ? 0 : 1;
1925 #endif
1926 #ifndef __U_BOOT__
1927                 pi->num_progs = save_num_progs; /* restore number of programs */
1928 #endif
1929                 if ( rmode == RES_IF || rmode == RES_ELIF )
1930                         next_if_code=rcode;  /* can be overwritten a number of times */
1931                 if (rmode == RES_WHILE)
1932                         flag_rep = !last_return_code;
1933                 if (rmode == RES_UNTIL)
1934                         flag_rep = last_return_code;
1935                 if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
1936                      (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
1937                         skip_more_in_this_rmode=rmode;
1938 #ifndef __U_BOOT__
1939                 checkjobs(NULL);
1940 #endif
1941         }
1942         return rcode;
1943 }
1944
1945 /* broken, of course, but OK for testing */
1946 static char *indenter(int i)
1947 {
1948         static char blanks[]="                                    ";
1949         return &blanks[sizeof(blanks)-i-1];
1950 }
1951
1952 /* return code is the exit status of the pipe */
1953 static int free_pipe(struct pipe *pi, int indent)
1954 {
1955         char **p;
1956         struct child_prog *child;
1957 #ifndef __U_BOOT__
1958         struct redir_struct *r, *rnext;
1959 #endif
1960         int a, i, ret_code=0;
1961         char *ind = indenter(indent);
1962
1963 #ifndef __U_BOOT__
1964         if (pi->stopped_progs > 0)
1965                 return ret_code;
1966         final_printf("%s run pipe: (pid %d)\n",ind,getpid());
1967 #endif
1968         for (i=0; i<pi->num_progs; i++) {
1969                 child = &pi->progs[i];
1970                 final_printf("%s  command %d:\n",ind,i);
1971                 if (child->argv) {
1972                         for (a=0,p=child->argv; *p; a++,p++) {
1973                                 final_printf("%s   argv[%d] = %s\n",ind,a,*p);
1974                         }
1975 #ifndef __U_BOOT__
1976                         globfree(&child->glob_result);
1977 #else
1978                         for (a = child->argc;a >= 0;a--) {
1979                                 free(child->argv[a]);
1980                         }
1981                                         free(child->argv);
1982                         child->argc = 0;
1983 #endif
1984                         child->argv=NULL;
1985                 } else if (child->group) {
1986 #ifndef __U_BOOT__
1987                         final_printf("%s   begin group (subshell:%d)\n",ind, child->subshell);
1988 #endif
1989                         ret_code = free_pipe_list(child->group,indent+3);
1990                         final_printf("%s   end group\n",ind);
1991                 } else {
1992                         final_printf("%s   (nil)\n",ind);
1993                 }
1994 #ifndef __U_BOOT__
1995                 for (r=child->redirects; r; r=rnext) {
1996                         final_printf("%s   redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
1997                         if (r->dup == -1) {
1998                                 /* guard against the case >$FOO, where foo is unset or blank */
1999                                 if (r->word.gl_pathv) {
2000                                         final_printf(" %s\n", *r->word.gl_pathv);
2001                                         globfree(&r->word);
2002                                 }
2003                         } else {
2004                                 final_printf("&%d\n", r->dup);
2005                         }
2006                         rnext=r->next;
2007                         free(r);
2008                 }
2009                 child->redirects=NULL;
2010 #endif
2011         }
2012         free(pi->progs);   /* children are an array, they get freed all at once */
2013         pi->progs=NULL;
2014         return ret_code;
2015 }
2016
2017 static int free_pipe_list(struct pipe *head, int indent)
2018 {
2019         int rcode=0;   /* if list has no members */
2020         struct pipe *pi, *next;
2021         char *ind = indenter(indent);
2022         for (pi=head; pi; pi=next) {
2023                 final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
2024                 rcode = free_pipe(pi, indent);
2025                 final_printf("%s pipe followup code %d\n", ind, pi->followup);
2026                 next=pi->next;
2027                 pi->next=NULL;
2028                 free(pi);
2029         }
2030         return rcode;
2031 }
2032
2033 /* Select which version we will use */
2034 static int run_list(struct pipe *pi)
2035 {
2036         int rcode=0;
2037 #ifndef __U_BOOT__
2038         if (fake_mode==0) {
2039 #endif
2040                 rcode = run_list_real(pi);
2041 #ifndef __U_BOOT__
2042         }
2043 #endif
2044         /* free_pipe_list has the side effect of clearing memory
2045          * In the long run that function can be merged with run_list_real,
2046          * but doing that now would hobble the debugging effort. */
2047         free_pipe_list(pi,0);
2048         return rcode;
2049 }
2050
2051 /* The API for glob is arguably broken.  This routine pushes a non-matching
2052  * string into the output structure, removing non-backslashed backslashes.
2053  * If someone can prove me wrong, by performing this function within the
2054  * original glob(3) api, feel free to rewrite this routine into oblivion.
2055  * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
2056  * XXX broken if the last character is '\\', check that before calling.
2057  */
2058 #ifndef __U_BOOT__
2059 static int globhack(const char *src, int flags, glob_t *pglob)
2060 {
2061         int cnt=0, pathc;
2062         const char *s;
2063         char *dest;
2064         for (cnt=1, s=src; s && *s; s++) {
2065                 if (*s == '\\') s++;
2066                 cnt++;
2067         }
2068         dest = malloc(cnt);
2069         if (!dest) return GLOB_NOSPACE;
2070         if (!(flags & GLOB_APPEND)) {
2071                 pglob->gl_pathv=NULL;
2072                 pglob->gl_pathc=0;
2073                 pglob->gl_offs=0;
2074                 pglob->gl_offs=0;
2075         }
2076         pathc = ++pglob->gl_pathc;
2077         pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
2078         if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
2079         pglob->gl_pathv[pathc-1]=dest;
2080         pglob->gl_pathv[pathc]=NULL;
2081         for (s=src; s && *s; s++, dest++) {
2082                 if (*s == '\\') s++;
2083                 *dest = *s;
2084         }
2085         *dest='\0';
2086         return 0;
2087 }
2088
2089 /* XXX broken if the last character is '\\', check that before calling */
2090 static int glob_needed(const char *s)
2091 {
2092         for (; *s; s++) {
2093                 if (*s == '\\') s++;
2094                 if (strchr("*[?",*s)) return 1;
2095         }
2096         return 0;
2097 }
2098
2099 #if 0
2100 static void globprint(glob_t *pglob)
2101 {
2102         int i;
2103         debug_printf("glob_t at %p:\n", pglob);
2104         debug_printf("  gl_pathc=%d  gl_pathv=%p  gl_offs=%d  gl_flags=%d\n",
2105                 pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
2106         for (i=0; i<pglob->gl_pathc; i++)
2107                 debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
2108                         pglob->gl_pathv[i], pglob->gl_pathv[i]);
2109 }
2110 #endif
2111
2112 static int xglob(o_string *dest, int flags, glob_t *pglob)
2113 {
2114         int gr;
2115
2116         /* short-circuit for null word */
2117         /* we can code this better when the debug_printf's are gone */
2118         if (dest->length == 0) {
2119                 if (dest->nonnull) {
2120                         /* bash man page calls this an "explicit" null */
2121                         gr = globhack(dest->data, flags, pglob);
2122                         debug_printf("globhack returned %d\n",gr);
2123                 } else {
2124                         return 0;
2125                 }
2126         } else if (glob_needed(dest->data)) {
2127                 gr = glob(dest->data, flags, NULL, pglob);
2128                 debug_printf("glob returned %d\n",gr);
2129                 if (gr == GLOB_NOMATCH) {
2130                         /* quote removal, or more accurately, backslash removal */
2131                         gr = globhack(dest->data, flags, pglob);
2132                         debug_printf("globhack returned %d\n",gr);
2133                 }
2134         } else {
2135                 gr = globhack(dest->data, flags, pglob);
2136                 debug_printf("globhack returned %d\n",gr);
2137         }
2138         if (gr == GLOB_NOSPACE)
2139                 error_msg_and_die("out of memory during glob");
2140         if (gr != 0) { /* GLOB_ABORTED ? */
2141                 error_msg("glob(3) error %d",gr);
2142         }
2143         /* globprint(glob_target); */
2144         return gr;
2145 }
2146 #endif
2147
2148 /* This is used to get/check local shell variables */
2149 static char *get_local_var(const char *s)
2150 {
2151         struct variables *cur;
2152
2153         if (!s)
2154                 return NULL;
2155         for (cur = top_vars; cur; cur=cur->next)
2156                 if(strcmp(cur->name, s)==0)
2157                         return cur->value;
2158         return NULL;
2159 }
2160
2161 /* This is used to set local shell variables
2162    flg_export==0 if only local (not exporting) variable
2163    flg_export==1 if "new" exporting environ
2164    flg_export>1  if current startup environ (not call putenv()) */
2165 static int set_local_var(const char *s, int flg_export)
2166 {
2167         char *name, *value;
2168         int result=0;
2169         struct variables *cur;
2170
2171         name=strdup(s);
2172
2173 #ifdef __U_BOOT__
2174         if (getenv(name) != NULL) {
2175                 printf ("ERROR: "
2176                                 "There is a global environment variable with the same name.\n");
2177                 return -1;
2178         }
2179 #endif
2180         /* Assume when we enter this function that we are already in
2181          * NAME=VALUE format.  So the first order of business is to
2182          * split 's' on the '=' into 'name' and 'value' */
2183         value = strchr(name, '=');
2184         if (value==0 && ++value==0) {
2185                 free(name);
2186                 return -1;
2187         }
2188         *value++ = 0;
2189
2190         for(cur = top_vars; cur; cur = cur->next) {
2191                 if(strcmp(cur->name, name)==0)
2192                         break;
2193         }
2194
2195         if(cur) {
2196                 if(strcmp(cur->value, value)==0) {
2197                         if(flg_export>0 && cur->flg_export==0)
2198                                 cur->flg_export=flg_export;
2199                         else
2200                                 result++;
2201                 } else {
2202                         if(cur->flg_read_only) {
2203                                 error_msg("%s: readonly variable", name);
2204                                 result = -1;
2205                         } else {
2206                                 if(flg_export>0 || cur->flg_export>1)
2207                                         cur->flg_export=1;
2208                                 free(cur->value);
2209
2210                                 cur->value = strdup(value);
2211                         }
2212                 }
2213         } else {
2214                 cur = malloc(sizeof(struct variables));
2215                 if(!cur) {
2216                         result = -1;
2217                 } else {
2218                         cur->name = strdup(name);
2219                         if(cur->name == 0) {
2220                                 free(cur);
2221                                 result = -1;
2222                         } else {
2223                                 struct variables *bottom = top_vars;
2224                                 cur->value = strdup(value);
2225                                 cur->next = 0;
2226                                 cur->flg_export = flg_export;
2227                                 cur->flg_read_only = 0;
2228                                 while(bottom->next) bottom=bottom->next;
2229                                 bottom->next = cur;
2230                         }
2231                 }
2232         }
2233
2234 #ifndef __U_BOOT__
2235         if(result==0 && cur->flg_export==1) {
2236                 *(value-1) = '=';
2237                 result = putenv(name);
2238         } else {
2239 #endif
2240                 free(name);
2241 #ifndef __U_BOOT__
2242                 if(result>0)            /* equivalent to previous set */
2243                         result = 0;
2244         }
2245 #endif
2246         return result;
2247 }
2248
2249 #ifndef __U_BOOT__
2250 static void unset_local_var(const char *name)
2251 {
2252         struct variables *cur;
2253
2254         if (name) {
2255                 for (cur = top_vars; cur; cur=cur->next) {
2256                         if(strcmp(cur->name, name)==0)
2257                                 break;
2258                 }
2259                 if(cur!=0) {
2260                         struct variables *next = top_vars;
2261                         if(cur->flg_read_only) {
2262                                 error_msg("%s: readonly variable", name);
2263                                 return;
2264                         } else {
2265                                 if(cur->flg_export)
2266                                         unsetenv(cur->name);
2267                                 free(cur->name);
2268                                 free(cur->value);
2269                                 while (next->next != cur)
2270                                         next = next->next;
2271                                 next->next = cur->next;
2272                         }
2273                         free(cur);
2274                 }
2275         }
2276 }
2277 #endif
2278
2279 static int is_assignment(const char *s)
2280 {
2281         if (s==NULL || !isalpha(*s)) return 0;
2282         ++s;
2283         while(isalnum(*s) || *s=='_') ++s;
2284         return *s=='=';
2285 }
2286
2287 #ifndef __U_BOOT__
2288 /* the src parameter allows us to peek forward to a possible &n syntax
2289  * for file descriptor duplication, e.g., "2>&1".
2290  * Return code is 0 normally, 1 if a syntax error is detected in src.
2291  * Resource errors (in xmalloc) cause the process to exit */
2292 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
2293         struct in_str *input)
2294 {
2295         struct child_prog *child=ctx->child;
2296         struct redir_struct *redir = child->redirects;
2297         struct redir_struct *last_redir=NULL;
2298
2299         /* Create a new redir_struct and drop it onto the end of the linked list */
2300         while(redir) {
2301                 last_redir=redir;
2302                 redir=redir->next;
2303         }
2304         redir = xmalloc(sizeof(struct redir_struct));
2305         redir->next=NULL;
2306         redir->word.gl_pathv=NULL;
2307         if (last_redir) {
2308                 last_redir->next=redir;
2309         } else {
2310                 child->redirects=redir;
2311         }
2312
2313         redir->type=style;
2314         redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
2315
2316         debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
2317
2318         /* Check for a '2>&1' type redirect */
2319         redir->dup = redirect_dup_num(input);
2320         if (redir->dup == -2) return 1;  /* syntax error */
2321         if (redir->dup != -1) {
2322                 /* Erik had a check here that the file descriptor in question
2323                  * is legit; I postpone that to "run time"
2324                  * A "-" representation of "close me" shows up as a -3 here */
2325                 debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
2326         } else {
2327                 /* We do _not_ try to open the file that src points to,
2328                  * since we need to return and let src be expanded first.
2329                  * Set ctx->pending_redirect, so we know what to do at the
2330                  * end of the next parsed word.
2331                  */
2332                 ctx->pending_redirect = redir;
2333         }
2334         return 0;
2335 }
2336 #endif
2337
2338 struct pipe *new_pipe(void) {
2339         struct pipe *pi;
2340         pi = xmalloc(sizeof(struct pipe));
2341         pi->num_progs = 0;
2342         pi->progs = NULL;
2343         pi->next = NULL;
2344         pi->followup = 0;  /* invalid */
2345         return pi;
2346 }
2347
2348 static void initialize_context(struct p_context *ctx)
2349 {
2350         ctx->pipe=NULL;
2351 #ifndef __U_BOOT__
2352         ctx->pending_redirect=NULL;
2353 #endif
2354         ctx->child=NULL;
2355         ctx->list_head=new_pipe();
2356         ctx->pipe=ctx->list_head;
2357         ctx->w=RES_NONE;
2358         ctx->stack=NULL;
2359 #ifdef __U_BOOT__
2360         ctx->old_flag=0;
2361 #endif
2362         done_command(ctx);   /* creates the memory for working child */
2363 }
2364
2365 /* normal return is 0
2366  * if a reserved word is found, and processed, return 1
2367  * should handle if, then, elif, else, fi, for, while, until, do, done.
2368  * case, function, and select are obnoxious, save those for later.
2369  */
2370 struct reserved_combo {
2371         char *literal;
2372         int code;
2373         long flag;
2374 };
2375 /* Mostly a list of accepted follow-up reserved words.
2376  * FLAG_END means we are done with the sequence, and are ready
2377  * to turn the compound list into a command.
2378  * FLAG_START means the word must start a new compound list.
2379  */
2380 static struct reserved_combo reserved_list[] = {
2381         { "if",    RES_IF,    FLAG_THEN | FLAG_START },
2382         { "then",  RES_THEN,  FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2383         { "elif",  RES_ELIF,  FLAG_THEN },
2384         { "else",  RES_ELSE,  FLAG_FI   },
2385         { "fi",    RES_FI,    FLAG_END  },
2386         { "for",   RES_FOR,   FLAG_IN   | FLAG_START },
2387         { "while", RES_WHILE, FLAG_DO   | FLAG_START },
2388         { "until", RES_UNTIL, FLAG_DO   | FLAG_START },
2389         { "in",    RES_IN,    FLAG_DO   },
2390         { "do",    RES_DO,    FLAG_DONE },
2391         { "done",  RES_DONE,  FLAG_END  }
2392 };
2393 #define NRES (sizeof(reserved_list)/sizeof(struct reserved_combo))
2394
2395 int reserved_word(o_string *dest, struct p_context *ctx)
2396 {
2397         struct reserved_combo *r;
2398         for (r=reserved_list;
2399                 r<reserved_list+NRES; r++) {
2400                 if (strcmp(dest->data, r->literal) == 0) {
2401                         debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2402                         if (r->flag & FLAG_START) {
2403                                 struct p_context *new = xmalloc(sizeof(struct p_context));
2404                                 debug_printf("push stack\n");
2405                                 if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2406                                         syntax();
2407                                         free(new);
2408                                         ctx->w = RES_SNTX;
2409                                         b_reset(dest);
2410                                         return 1;
2411                                 }
2412                                 *new = *ctx;   /* physical copy */
2413                                 initialize_context(ctx);
2414                                 ctx->stack=new;
2415                         } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2416                                 syntax();
2417                                 ctx->w = RES_SNTX;
2418                                 b_reset(dest);
2419                                 return 1;
2420                         }
2421                         ctx->w=r->code;
2422                         ctx->old_flag = r->flag;
2423                         if (ctx->old_flag & FLAG_END) {
2424                                 struct p_context *old;
2425                                 debug_printf("pop stack\n");
2426                                 done_pipe(ctx,PIPE_SEQ);
2427                                 old = ctx->stack;
2428                                 old->child->group = ctx->list_head;
2429 #ifndef __U_BOOT__
2430                                 old->child->subshell = 0;
2431 #endif
2432                                 *ctx = *old;   /* physical copy */
2433                                 free(old);
2434                         }
2435                         b_reset (dest);
2436                         return 1;
2437                 }
2438         }
2439         return 0;
2440 }
2441
2442 /* normal return is 0.
2443  * Syntax or xglob errors return 1. */
2444 static int done_word(o_string *dest, struct p_context *ctx)
2445 {
2446         struct child_prog *child=ctx->child;
2447 #ifndef __U_BOOT__
2448         glob_t *glob_target;
2449         int gr, flags = 0;
2450 #else
2451         char *str, *s;
2452         int argc, cnt;
2453 #endif
2454
2455         debug_printf("done_word: %s %p\n", dest->data, child);
2456         if (dest->length == 0 && !dest->nonnull) {
2457                 debug_printf("  true null, ignored\n");
2458                 return 0;
2459         }
2460 #ifndef __U_BOOT__
2461         if (ctx->pending_redirect) {
2462                 glob_target = &ctx->pending_redirect->word;
2463         } else {
2464 #endif
2465                 if (child->group) {
2466                         syntax();
2467                         return 1;  /* syntax error, groups and arglists don't mix */
2468                 }
2469                 if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2470                         debug_printf("checking %s for reserved-ness\n",dest->data);
2471                         if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2472                 }
2473 #ifndef __U_BOOT__
2474                 glob_target = &child->glob_result;
2475                 if (child->argv) flags |= GLOB_APPEND;
2476 #else
2477                 for (cnt = 1, s = dest->data; s && *s; s++) {
2478                         if (*s == '\\') s++;
2479                         cnt++;
2480                 }
2481                 str = malloc(cnt);
2482                 if (!str) return 1;
2483                 if ( child->argv == NULL) {
2484                         child->argc=0;
2485                 }
2486                 argc = ++child->argc;
2487                 child->argv = realloc(child->argv, (argc+1)*sizeof(*child->argv));
2488                 if (child->argv == NULL) return 1;
2489                 child->argv[argc-1]=str;
2490                 child->argv[argc]=NULL;
2491                 for (s = dest->data; s && *s; s++,str++) {
2492                         if (*s == '\\') s++;
2493                         *str = *s;
2494                 }
2495                 *str = '\0';
2496 #endif
2497 #ifndef __U_BOOT__
2498         }
2499         gr = xglob(dest, flags, glob_target);
2500         if (gr != 0) return 1;
2501 #endif
2502
2503         b_reset(dest);
2504 #ifndef __U_BOOT__
2505         if (ctx->pending_redirect) {
2506                 ctx->pending_redirect=NULL;
2507                 if (glob_target->gl_pathc != 1) {
2508                         error_msg("ambiguous redirect");
2509                         return 1;
2510                 }
2511         } else {
2512                 child->argv = glob_target->gl_pathv;
2513         }
2514 #endif
2515         if (ctx->w == RES_FOR) {
2516                 done_word(dest,ctx);
2517                 done_pipe(ctx,PIPE_SEQ);
2518         }
2519         return 0;
2520 }
2521
2522 /* The only possible error here is out of memory, in which case
2523  * xmalloc exits. */
2524 static int done_command(struct p_context *ctx)
2525 {
2526         /* The child is really already in the pipe structure, so
2527          * advance the pipe counter and make a new, null child.
2528          * Only real trickiness here is that the uncommitted
2529          * child structure, to which ctx->child points, is not
2530          * counted in pi->num_progs. */
2531         struct pipe *pi=ctx->pipe;
2532         struct child_prog *prog=ctx->child;
2533
2534         if (prog && prog->group == NULL
2535                  && prog->argv == NULL
2536 #ifndef __U_BOOT__
2537                  && prog->redirects == NULL) {
2538 #else
2539                                                                                 ) {
2540 #endif
2541                 debug_printf("done_command: skipping null command\n");
2542                 return 0;
2543         } else if (prog) {
2544                 pi->num_progs++;
2545                 debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2546         } else {
2547                 debug_printf("done_command: initializing\n");
2548         }
2549         pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2550
2551         prog = pi->progs + pi->num_progs;
2552 #ifndef __U_BOOT__
2553         prog->redirects = NULL;
2554 #endif
2555         prog->argv = NULL;
2556 #ifndef __U_BOOT__
2557         prog->is_stopped = 0;
2558 #endif
2559         prog->group = NULL;
2560 #ifndef __U_BOOT__
2561         prog->glob_result.gl_pathv = NULL;
2562         prog->family = pi;
2563 #endif
2564         prog->sp = 0;
2565         ctx->child = prog;
2566         prog->type = ctx->type;
2567
2568         /* but ctx->pipe and ctx->list_head remain unchanged */
2569         return 0;
2570 }
2571
2572 static int done_pipe(struct p_context *ctx, pipe_style type)
2573 {
2574         struct pipe *new_p;
2575         done_command(ctx);  /* implicit closure of previous command */
2576         debug_printf("done_pipe, type %d\n", type);
2577         ctx->pipe->followup = type;
2578         ctx->pipe->r_mode = ctx->w;
2579         new_p=new_pipe();
2580         ctx->pipe->next = new_p;
2581         ctx->pipe = new_p;
2582         ctx->child = NULL;
2583         done_command(ctx);  /* set up new pipe to accept commands */
2584         return 0;
2585 }
2586
2587 #ifndef __U_BOOT__
2588 /* peek ahead in the in_str to find out if we have a "&n" construct,
2589  * as in "2>&1", that represents duplicating a file descriptor.
2590  * returns either -2 (syntax error), -1 (no &), or the number found.
2591  */
2592 static int redirect_dup_num(struct in_str *input)
2593 {
2594         int ch, d=0, ok=0;
2595         ch = b_peek(input);
2596         if (ch != '&') return -1;
2597
2598         b_getch(input);  /* get the & */
2599         ch=b_peek(input);
2600         if (ch == '-') {
2601                 b_getch(input);
2602                 return -3;  /* "-" represents "close me" */
2603         }
2604         while (isdigit(ch)) {
2605                 d = d*10+(ch-'0');
2606                 ok=1;
2607                 b_getch(input);
2608                 ch = b_peek(input);
2609         }
2610         if (ok) return d;
2611
2612         error_msg("ambiguous redirect");
2613         return -2;
2614 }
2615
2616 /* If a redirect is immediately preceded by a number, that number is
2617  * supposed to tell which file descriptor to redirect.  This routine
2618  * looks for such preceding numbers.  In an ideal world this routine
2619  * needs to handle all the following classes of redirects...
2620  *     echo 2>foo     # redirects fd  2 to file "foo", nothing passed to echo
2621  *     echo 49>foo    # redirects fd 49 to file "foo", nothing passed to echo
2622  *     echo -2>foo    # redirects fd  1 to file "foo",    "-2" passed to echo
2623  *     echo 49x>foo   # redirects fd  1 to file "foo",   "49x" passed to echo
2624  * A -1 output from this program means no valid number was found, so the
2625  * caller should use the appropriate default for this redirection.
2626  */
2627 static int redirect_opt_num(o_string *o)
2628 {
2629         int num;
2630
2631         if (o->length==0) return -1;
2632         for(num=0; num<o->length; num++) {
2633                 if (!isdigit(*(o->data+num))) {
2634                         return -1;
2635                 }
2636         }
2637         /* reuse num (and save an int) */
2638         num=atoi(o->data);
2639         b_reset(o);
2640         return num;
2641 }
2642
2643 FILE *generate_stream_from_list(struct pipe *head)
2644 {
2645         FILE *pf;
2646 #if 1
2647         int pid, channel[2];
2648         if (pipe(channel)<0) perror_msg_and_die("pipe");
2649         pid=fork();
2650         if (pid<0) {
2651                 perror_msg_and_die("fork");
2652         } else if (pid==0) {
2653                 close(channel[0]);
2654                 if (channel[1] != 1) {
2655                         dup2(channel[1],1);
2656                         close(channel[1]);
2657                 }
2658 #if 0
2659 #define SURROGATE "surrogate response"
2660                 write(1,SURROGATE,sizeof(SURROGATE));
2661                 _exit(run_list(head));
2662 #else
2663                 _exit(run_list_real(head));   /* leaks memory */
2664 #endif
2665         }
2666         debug_printf("forked child %d\n",pid);
2667         close(channel[1]);
2668         pf = fdopen(channel[0],"r");
2669         debug_printf("pipe on FILE *%p\n",pf);
2670 #else
2671         free_pipe_list(head,0);
2672         pf=popen("echo surrogate response","r");
2673         debug_printf("started fake pipe on FILE *%p\n",pf);
2674 #endif
2675         return pf;
2676 }
2677
2678 /* this version hacked for testing purposes */
2679 /* return code is exit status of the process that is run. */
2680 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2681 {
2682         int retcode;
2683         o_string result=NULL_O_STRING;
2684         struct p_context inner;
2685         FILE *p;
2686         struct in_str pipe_str;
2687         initialize_context(&inner);
2688
2689         /* recursion to generate command */
2690         retcode = parse_stream(&result, &inner, input, subst_end);
2691         if (retcode != 0) return retcode;  /* syntax error or EOF */
2692         done_word(&result, &inner);
2693         done_pipe(&inner, PIPE_SEQ);
2694         b_free(&result);
2695
2696         p=generate_stream_from_list(inner.list_head);
2697         if (p==NULL) return 1;
2698         mark_open(fileno(p));
2699         setup_file_in_str(&pipe_str, p);
2700
2701         /* now send results of command back into original context */
2702         retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2703         /* XXX In case of a syntax error, should we try to kill the child?
2704          * That would be tough to do right, so just read until EOF. */
2705         if (retcode == 1) {
2706                 while (b_getch(&pipe_str)!=EOF) { /* discard */ };
2707         }
2708
2709         debug_printf("done reading from pipe, pclose()ing\n");
2710         /* This is the step that wait()s for the child.  Should be pretty
2711          * safe, since we just read an EOF from its stdout.  We could try
2712          * to better, by using wait(), and keeping track of background jobs
2713          * at the same time.  That would be a lot of work, and contrary
2714          * to the KISS philosophy of this program. */
2715         mark_closed(fileno(p));
2716         retcode=pclose(p);
2717         free_pipe_list(inner.list_head,0);
2718         debug_printf("pclosed, retcode=%d\n",retcode);
2719         /* XXX this process fails to trim a single trailing newline */
2720         return retcode;
2721 }
2722
2723 static int parse_group(o_string *dest, struct p_context *ctx,
2724         struct in_str *input, int ch)
2725 {
2726         int rcode, endch=0;
2727         struct p_context sub;
2728         struct child_prog *child = ctx->child;
2729         if (child->argv) {
2730                 syntax();
2731                 return 1;  /* syntax error, groups and arglists don't mix */
2732         }
2733         initialize_context(&sub);
2734         switch(ch) {
2735                 case '(': endch=')'; child->subshell=1; break;
2736                 case '{': endch='}'; break;
2737                 default: syntax();   /* really logic error */
2738         }
2739         rcode=parse_stream(dest,&sub,input,endch);
2740         done_word(dest,&sub); /* finish off the final word in the subcontext */
2741         done_pipe(&sub, PIPE_SEQ);  /* and the final command there, too */
2742         child->group = sub.list_head;
2743         return rcode;
2744         /* child remains "open", available for possible redirects */
2745 }
2746 #endif
2747
2748 /* basically useful version until someone wants to get fancier,
2749  * see the bash man page under "Parameter Expansion" */
2750 static char *lookup_param(char *src)
2751 {
2752         char *p=NULL;
2753         if (src) {
2754                 p = getenv(src);
2755                 if (!p)
2756                         p = get_local_var(src);
2757         }
2758         return p;
2759 }
2760
2761 /* return code: 0 for OK, 1 for syntax error */
2762 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2763 {
2764 #ifndef __U_BOOT__
2765         int i, advance=0;
2766 #else
2767         int advance=0;
2768 #endif
2769 #ifndef __U_BOOT__
2770         char sep[]=" ";
2771 #endif
2772         int ch = input->peek(input);  /* first character after the $ */
2773         debug_printf("handle_dollar: ch=%c\n",ch);
2774         if (isalpha(ch)) {
2775                 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2776                 ctx->child->sp++;
2777                 while(ch=b_peek(input),isalnum(ch) || ch=='_') {
2778                         b_getch(input);
2779                         b_addchr(dest,ch);
2780                 }
2781                 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2782 #ifndef __U_BOOT__
2783         } else if (isdigit(ch)) {
2784                 i = ch-'0';  /* XXX is $0 special? */
2785                 if (i<global_argc) {
2786                         parse_string(dest, ctx, global_argv[i]); /* recursion */
2787                 }
2788                 advance = 1;
2789 #endif
2790         } else switch (ch) {
2791 #ifndef __U_BOOT__
2792                 case '$':
2793                         b_adduint(dest,getpid());
2794                         advance = 1;
2795                         break;
2796                 case '!':
2797                         if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2798                         advance = 1;
2799                         break;
2800 #endif
2801                 case '?':
2802                         b_adduint(dest,last_return_code);
2803                         advance = 1;
2804                         break;
2805 #ifndef __U_BOOT__
2806                 case '#':
2807                         b_adduint(dest,global_argc ? global_argc-1 : 0);
2808                         advance = 1;
2809                         break;
2810 #endif
2811                 case '{':
2812                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2813                         ctx->child->sp++;
2814                         b_getch(input);
2815                         /* XXX maybe someone will try to escape the '}' */
2816                         while(ch=b_getch(input),ch!=EOF && ch!='}') {
2817                                 b_addchr(dest,ch);
2818                         }
2819                         if (ch != '}') {
2820                                 syntax();
2821                                 return 1;
2822                         }
2823                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2824                         break;
2825 #ifndef __U_BOOT__
2826                 case '(':
2827                         b_getch(input);
2828                         process_command_subs(dest, ctx, input, ')');
2829                         break;
2830                 case '*':
2831                         sep[0]=ifs[0];
2832                         for (i=1; i<global_argc; i++) {
2833                                 parse_string(dest, ctx, global_argv[i]);
2834                                 if (i+1 < global_argc) parse_string(dest, ctx, sep);
2835                         }
2836                         break;
2837                 case '@':
2838                 case '-':
2839                 case '_':
2840                         /* still unhandled, but should be eventually */
2841                         error_msg("unhandled syntax: $%c",ch);
2842                         return 1;
2843                         break;
2844 #endif
2845                 default:
2846                         b_addqchr(dest,'$',dest->quote);
2847         }
2848         /* Eat the character if the flag was set.  If the compiler
2849          * is smart enough, we could substitute "b_getch(input);"
2850          * for all the "advance = 1;" above, and also end up with
2851          * a nice size-optimized program.  Hah!  That'll be the day.
2852          */
2853         if (advance) b_getch(input);
2854         return 0;
2855 }
2856
2857 #ifndef __U_BOOT__
2858 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2859 {
2860         struct in_str foo;
2861         setup_string_in_str(&foo, src);
2862         return parse_stream(dest, ctx, &foo, '\0');
2863 }
2864 #endif
2865
2866 /* return code is 0 for normal exit, 1 for syntax error */
2867 int parse_stream(o_string *dest, struct p_context *ctx,
2868         struct in_str *input, int end_trigger)
2869 {
2870         unsigned int ch, m;
2871 #ifndef __U_BOOT__
2872         int redir_fd;
2873         redir_type redir_style;
2874 #endif
2875         int next;
2876
2877         /* Only double-quote state is handled in the state variable dest->quote.
2878          * A single-quote triggers a bypass of the main loop until its mate is
2879          * found.  When recursing, quote state is passed in via dest->quote. */
2880
2881         debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2882         while ((ch=b_getch(input))!=EOF) {
2883                 m = map[ch];
2884 #ifdef __U_BOOT__
2885                 if (input->__promptme == 0) return 1;
2886 #endif
2887                 next = (ch == '\n') ? 0 : b_peek(input);
2888                 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d\n",
2889                         ch,ch,m,dest->quote);
2890                 if (m==0 || ((m==1 || m==2) && dest->quote)) {
2891                         b_addqchr(dest, ch, dest->quote);
2892                 } else {
2893                         if (m==2) {  /* unquoted IFS */
2894                                 if (done_word(dest, ctx)) {
2895                                         return 1;
2896                                 }
2897                                 /* If we aren't performing a substitution, treat a newline as a
2898                                  * command separator.  */
2899                                 if (end_trigger != '\0' && ch=='\n')
2900                                         done_pipe(ctx,PIPE_SEQ);
2901                         }
2902                         if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2903                                 debug_printf("leaving parse_stream (triggered)\n");
2904                                 return 0;
2905                         }
2906 #if 0
2907                         if (ch=='\n') {
2908                                 /* Yahoo!  Time to run with it! */
2909                                 done_pipe(ctx,PIPE_SEQ);
2910                                 run_list(ctx->list_head);
2911                                 initialize_context(ctx);
2912                         }
2913 #endif
2914                         if (m!=2) switch (ch) {
2915                 case '#':
2916                         if (dest->length == 0 && !dest->quote) {
2917                                 while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
2918                         } else {
2919                                 b_addqchr(dest, ch, dest->quote);
2920                         }
2921                         break;
2922                 case '\\':
2923                         if (next == EOF) {
2924                                 syntax();
2925                                 return 1;
2926                         }
2927                         b_addqchr(dest, '\\', dest->quote);
2928                         b_addqchr(dest, b_getch(input), dest->quote);
2929                         break;
2930                 case '$':
2931                         if (handle_dollar(dest, ctx, input)!=0) return 1;
2932                         break;
2933                 case '\'':
2934                         dest->nonnull = 1;
2935                         while(ch=b_getch(input),ch!=EOF && ch!='\'') {
2936 #ifdef __U_BOOT__
2937                                 if(input->__promptme == 0) return 1;
2938 #endif
2939                                 b_addchr(dest,ch);
2940                         }
2941                         if (ch==EOF) {
2942                                 syntax();
2943                                 return 1;
2944                         }
2945                         break;
2946                 case '"':
2947                         dest->nonnull = 1;
2948                         dest->quote = !dest->quote;
2949                         break;
2950 #ifndef __U_BOOT__
2951                 case '`':
2952                         process_command_subs(dest, ctx, input, '`');
2953                         break;
2954                 case '>':
2955                         redir_fd = redirect_opt_num(dest);
2956                         done_word(dest, ctx);
2957                         redir_style=REDIRECT_OVERWRITE;
2958                         if (next == '>') {
2959                                 redir_style=REDIRECT_APPEND;
2960                                 b_getch(input);
2961                         } else if (next == '(') {
2962                                 syntax();   /* until we support >(list) Process Substitution */
2963                                 return 1;
2964                         }
2965                         setup_redirect(ctx, redir_fd, redir_style, input);
2966                         break;
2967                 case '<':
2968                         redir_fd = redirect_opt_num(dest);
2969                         done_word(dest, ctx);
2970                         redir_style=REDIRECT_INPUT;
2971                         if (next == '<') {
2972                                 redir_style=REDIRECT_HEREIS;
2973                                 b_getch(input);
2974                         } else if (next == '>') {
2975                                 redir_style=REDIRECT_IO;
2976                                 b_getch(input);
2977                         } else if (next == '(') {
2978                                 syntax();   /* until we support <(list) Process Substitution */
2979                                 return 1;
2980                         }
2981                         setup_redirect(ctx, redir_fd, redir_style, input);
2982                         break;
2983 #endif
2984                 case ';':
2985                         done_word(dest, ctx);
2986                         done_pipe(ctx,PIPE_SEQ);
2987                         break;
2988                 case '&':
2989                         done_word(dest, ctx);
2990                         if (next=='&') {
2991                                 b_getch(input);
2992                                 done_pipe(ctx,PIPE_AND);
2993                         } else {
2994 #ifndef __U_BOOT__
2995                                 done_pipe(ctx,PIPE_BG);
2996 #else
2997                                 syntax_err();
2998                                 return 1;
2999 #endif
3000                         }
3001                         break;
3002                 case '|':
3003                         done_word(dest, ctx);
3004                         if (next=='|') {
3005                                 b_getch(input);
3006                                 done_pipe(ctx,PIPE_OR);
3007                         } else {
3008                                 /* we could pick up a file descriptor choice here
3009                                  * with redirect_opt_num(), but bash doesn't do it.
3010                                  * "echo foo 2| cat" yields "foo 2". */
3011 #ifndef __U_BOOT__
3012                                 done_command(ctx);
3013 #else
3014                                 syntax_err();
3015                                 return 1;
3016 #endif
3017                         }
3018                         break;
3019 #ifndef __U_BOOT__
3020                 case '(':
3021                 case '{':
3022                         if (parse_group(dest, ctx, input, ch)!=0) return 1;
3023                         break;
3024                 case ')':
3025                 case '}':
3026                         syntax();   /* Proper use of this character caught by end_trigger */
3027                         return 1;
3028                         break;
3029 #endif
3030                 default:
3031                         syntax();   /* this is really an internal logic error */
3032                         return 1;
3033                         }
3034                 }
3035         }
3036         /* complain if quote?  No, maybe we just finished a command substitution
3037          * that was quoted.  Example:
3038          * $ echo "`cat foo` plus more"
3039          * and we just got the EOF generated by the subshell that ran "cat foo"
3040          * The only real complaint is if we got an EOF when end_trigger != '\0',
3041          * that is, we were really supposed to get end_trigger, and never got
3042          * one before the EOF.  Can't use the standard "syntax error" return code,
3043          * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
3044         debug_printf("leaving parse_stream (EOF)\n");
3045         if (end_trigger != '\0') return -1;
3046         return 0;
3047 }
3048
3049 void mapset(const unsigned char *set, int code)
3050 {
3051         const unsigned char *s;
3052         for (s=set; *s; s++) map[*s] = code;
3053 }
3054
3055 void update_ifs_map(void)
3056 {
3057         /* char *ifs and char map[256] are both globals. */
3058         ifs = getenv("IFS");
3059         if (ifs == NULL) ifs=" \t\n";
3060         /* Precompute a list of 'flow through' behavior so it can be treated
3061          * quickly up front.  Computation is necessary because of IFS.
3062          * Special case handling of IFS == " \t\n" is not implemented.
3063          * The map[] array only really needs two bits each, and on most machines
3064          * that would be faster because of the reduced L1 cache footprint.
3065          */
3066         memset(map,0,sizeof(map)); /* most characters flow through always */
3067 #ifndef __U_BOOT__
3068         mapset("\\$'\"`", 3);      /* never flow through */
3069         mapset("<>;&|(){}#", 1);   /* flow through if quoted */
3070 #else
3071         mapset("\\$'\"", 3);       /* never flow through */
3072         mapset(";&|#", 1);         /* flow through if quoted */
3073 #endif
3074         mapset(ifs, 2);            /* also flow through if quoted */
3075 }
3076
3077 /* most recursion does not come through here, the exeception is
3078  * from builtin_source() */
3079 int parse_stream_outer(struct in_str *inp, int flag)
3080 {
3081
3082         struct p_context ctx;
3083         o_string temp=NULL_O_STRING;
3084         int rcode;
3085 #ifdef __U_BOOT__
3086         int code = 0;
3087 #endif
3088         do {
3089                 ctx.type = flag;
3090                 initialize_context(&ctx);
3091                 update_ifs_map();
3092                 if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset(";$&|", 0);
3093                 inp->promptmode=1;
3094                 rcode = parse_stream(&temp, &ctx, inp, '\n');
3095 #ifdef __U_BOOT__
3096                 if (rcode == 1) flag_repeat = 0;
3097 #endif
3098                 if (rcode != 1 && ctx.old_flag != 0) {
3099                         syntax();
3100 #ifdef __U_BOOT__
3101                         flag_repeat = 0;
3102 #endif
3103                 }
3104                 if (rcode != 1 && ctx.old_flag == 0) {
3105                         done_word(&temp, &ctx);
3106                         done_pipe(&ctx,PIPE_SEQ);
3107 #ifndef __U_BOOT__
3108                         run_list(ctx.list_head);
3109 #else
3110                         if (((code = run_list(ctx.list_head)) == -1))
3111                             flag_repeat = 0;
3112 #endif
3113                 } else {
3114                         if (ctx.old_flag != 0) {
3115                                 free(ctx.stack);
3116                                 b_reset(&temp);
3117                         }
3118 #ifdef __U_BOOT__
3119                         if (inp->__promptme == 0) printf("<INTERRUPT>\n");
3120                         inp->__promptme = 1;
3121 #endif
3122                         temp.nonnull = 0;
3123                         temp.quote = 0;
3124                         inp->p = NULL;
3125                         free_pipe_list(ctx.list_head,0);
3126                 }
3127                 b_free(&temp);
3128         } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP));   /* loop on syntax errors, return on EOF */
3129 #ifndef __U_BOOT__
3130         return 0;
3131 #else
3132         return (code != 0) ? 1 : 0;
3133 #endif /* __U_BOOT__ */
3134 }
3135
3136 #ifndef __U_BOOT__
3137 static int parse_string_outer(const char *s, int flag)
3138 #else
3139 int parse_string_outer(char *s, int flag)
3140 #endif  /* __U_BOOT__ */
3141 {
3142         struct in_str input;
3143 #ifdef __U_BOOT__
3144         char *p = NULL;
3145         int rcode;
3146         if ( !s || !*s)
3147                 return 1;
3148         if (!(p = strchr(s, '\n')) || *++p) {
3149                 p = xmalloc(strlen(s) + 2);
3150                 strcpy(p, s);
3151                 strcat(p, "\n");
3152                 setup_string_in_str(&input, p);
3153                 rcode = parse_stream_outer(&input, flag);
3154                 free(p);
3155                 return rcode;
3156         } else {
3157 #endif
3158         setup_string_in_str(&input, s);
3159         return parse_stream_outer(&input, flag);
3160 #ifdef __U_BOOT__
3161         }
3162 #endif
3163 }
3164
3165 #ifndef __U_BOOT__
3166 static int parse_file_outer(FILE *f)
3167 #else
3168 int parse_file_outer(void)
3169 #endif
3170 {
3171         int rcode;
3172         struct in_str input;
3173 #ifndef __U_BOOT__
3174         setup_file_in_str(&input, f);
3175 #else
3176         setup_file_in_str(&input);
3177 #endif
3178         rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
3179         return rcode;
3180 }
3181
3182 #ifdef __U_BOOT__
3183 static void u_boot_hush_reloc(void)
3184 {
3185         DECLARE_GLOBAL_DATA_PTR;
3186         unsigned long addr;
3187         struct reserved_combo *r;
3188
3189         for (r=reserved_list; r<reserved_list+NRES; r++) {
3190                 addr = (ulong) (r->literal) + gd->reloc_off;
3191                 r->literal = (char *)addr;
3192         }
3193 }
3194
3195 int u_boot_hush_start(void)
3196 {
3197         if (top_vars == NULL) {
3198                 top_vars = malloc(sizeof(struct variables));
3199                 top_vars->name = "HUSH_VERSION";
3200                 top_vars->value = "0.01";
3201                 top_vars->next = 0;
3202                 top_vars->flg_export = 0;
3203                 top_vars->flg_read_only = 1;
3204                 u_boot_hush_reloc();
3205         }
3206         return 0;
3207 }
3208
3209 static void *xmalloc(size_t size)
3210 {
3211         void *p = NULL;
3212
3213         if (!(p = malloc(size))) {
3214             printf("ERROR : memory not allocated\n");
3215             for(;;);
3216         }
3217         return p;
3218 }
3219
3220 static void *xrealloc(void *ptr, size_t size)
3221 {
3222         void *p = NULL;
3223
3224         if (!(p = realloc(ptr, size))) {
3225             printf("ERROR : memory not allocated\n");
3226             for(;;);
3227         }
3228         return p;
3229 }
3230 #endif /* __U_BOOT__ */
3231
3232 #ifndef __U_BOOT__
3233 /* Make sure we have a controlling tty.  If we get started under a job
3234  * aware app (like bash for example), make sure we are now in charge so
3235  * we don't fight over who gets the foreground */
3236 static void setup_job_control(void)
3237 {
3238         static pid_t shell_pgrp;
3239         /* Loop until we are in the foreground.  */
3240         while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
3241                 kill (- shell_pgrp, SIGTTIN);
3242
3243         /* Ignore interactive and job-control signals.  */
3244         signal(SIGINT, SIG_IGN);
3245         signal(SIGQUIT, SIG_IGN);
3246         signal(SIGTERM, SIG_IGN);
3247         signal(SIGTSTP, SIG_IGN);
3248         signal(SIGTTIN, SIG_IGN);
3249         signal(SIGTTOU, SIG_IGN);
3250         signal(SIGCHLD, SIG_IGN);
3251
3252         /* Put ourselves in our own process group.  */
3253         setsid();
3254         shell_pgrp = getpid ();
3255         setpgid (shell_pgrp, shell_pgrp);
3256
3257         /* Grab control of the terminal.  */
3258         tcsetpgrp(shell_terminal, shell_pgrp);
3259 }
3260
3261 int hush_main(int argc, char **argv)
3262 {
3263         int opt;
3264         FILE *input;
3265         char **e = environ;
3266
3267         /* XXX what should these be while sourcing /etc/profile? */
3268         global_argc = argc;
3269         global_argv = argv;
3270
3271         /* (re?) initialize globals.  Sometimes hush_main() ends up calling
3272          * hush_main(), therefore we cannot rely on the BSS to zero out this
3273          * stuff.  Reset these to 0 every time. */
3274         ifs = NULL;
3275         /* map[] is taken care of with call to update_ifs_map() */
3276         fake_mode = 0;
3277         interactive = 0;
3278         close_me_head = NULL;
3279         last_bg_pid = 0;
3280         job_list = NULL;
3281         last_jobid = 0;
3282
3283         /* Initialize some more globals to non-zero values */
3284         set_cwd();
3285 #ifdef CONFIG_FEATURE_COMMAND_EDITING
3286         cmdedit_set_initial_prompt();
3287 #else
3288         PS1 = NULL;
3289 #endif
3290         PS2 = "> ";
3291
3292         /* initialize our shell local variables with the values
3293          * currently living in the environment */
3294         if (e) {
3295                 for (; *e; e++)
3296                         set_local_var(*e, 2);   /* without call putenv() */
3297         }
3298
3299         last_return_code=EXIT_SUCCESS;
3300
3301
3302         if (argv[0] && argv[0][0] == '-') {
3303                 debug_printf("\nsourcing /etc/profile\n");
3304                 if ((input = fopen("/etc/profile", "r")) != NULL) {
3305                         mark_open(fileno(input));
3306                         parse_file_outer(input);
3307                         mark_closed(fileno(input));
3308                         fclose(input);
3309                 }
3310         }
3311         input=stdin;
3312
3313         while ((opt = getopt(argc, argv, "c:xif")) > 0) {
3314                 switch (opt) {
3315                         case 'c':
3316                                 {
3317                                         global_argv = argv+optind;
3318                                         global_argc = argc-optind;
3319                                         opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
3320                                         goto final_return;
3321                                 }
3322                                 break;
3323                         case 'i':
3324                                 interactive++;
3325                                 break;
3326                         case 'f':
3327                                 fake_mode++;
3328                                 break;
3329                         default:
3330 #ifndef BB_VER
3331                                 fprintf(stderr, "Usage: sh [FILE]...\n"
3332                                                 "   or: sh -c command [args]...\n\n");
3333                                 exit(EXIT_FAILURE);
3334 #else
3335                                 show_usage();
3336 #endif
3337                 }
3338         }
3339         /* A shell is interactive if the `-i' flag was given, or if all of
3340          * the following conditions are met:
3341          *        no -c command
3342          *    no arguments remaining or the -s flag given
3343          *    standard input is a terminal
3344          *    standard output is a terminal
3345          *    Refer to Posix.2, the description of the `sh' utility. */
3346         if (argv[optind]==NULL && input==stdin &&
3347                         isatty(fileno(stdin)) && isatty(fileno(stdout))) {
3348                 interactive++;
3349         }
3350
3351         debug_printf("\ninteractive=%d\n", interactive);
3352         if (interactive) {
3353                 /* Looks like they want an interactive shell */
3354 #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
3355                 printf( "\n\n" BB_BANNER " hush - the humble shell v0.01 (testing)\n");
3356                 printf( "Enter 'help' for a list of built-in commands.\n\n");
3357 #endif
3358                 setup_job_control();
3359         }
3360
3361         if (argv[optind]==NULL) {
3362                 opt=parse_file_outer(stdin);
3363                 goto final_return;
3364         }
3365
3366         debug_printf("\nrunning script '%s'\n", argv[optind]);
3367         global_argv = argv+optind;
3368         global_argc = argc-optind;
3369         input = xfopen(argv[optind], "r");
3370         opt = parse_file_outer(input);
3371
3372 #ifdef CONFIG_FEATURE_CLEAN_UP
3373         fclose(input);
3374         if (cwd && cwd != unknown)
3375                 free((char*)cwd);
3376         {
3377                 struct variables *cur, *tmp;
3378                 for(cur = top_vars; cur; cur = tmp) {
3379                         tmp = cur->next;
3380                         if (!cur->flg_read_only) {
3381                                 free(cur->name);
3382                                 free(cur->value);
3383                                 free(cur);
3384                         }
3385                 }
3386         }
3387 #endif
3388
3389 final_return:
3390         return(opt?opt:last_return_code);
3391 }
3392 #endif
3393
3394 static char *insert_var_value(char *inp)
3395 {
3396         int res_str_len = 0;
3397         int len;
3398         int done = 0;
3399         char *p, *p1, *res_str = NULL;
3400
3401         while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
3402                 if (p != inp) {
3403                         len = p - inp;
3404                         res_str = xrealloc(res_str, (res_str_len + len));
3405                         strncpy((res_str + res_str_len), inp, len);
3406                         res_str_len += len;
3407                 }
3408                 inp = ++p;
3409                 p = strchr(inp, SPECIAL_VAR_SYMBOL);
3410                 *p = '\0';
3411                 if ((p1 = lookup_param(inp))) {
3412                         len = res_str_len + strlen(p1);
3413                         res_str = xrealloc(res_str, (1 + len));
3414                         strcpy((res_str + res_str_len), p1);
3415                         res_str_len = len;
3416                 }
3417                 *p = SPECIAL_VAR_SYMBOL;
3418                 inp = ++p;
3419                 done = 1;
3420         }
3421         if (done) {
3422                 res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
3423                 strcpy((res_str + res_str_len), inp);
3424                 while ((p = strchr(res_str, '\n'))) {
3425                         *p = ' ';
3426                 }
3427         }
3428         return (res_str == NULL) ? inp : res_str;
3429 }
3430
3431 static char **make_list_in(char **inp, char *name)
3432 {
3433         int len, i;
3434         int name_len = strlen(name);
3435         int n = 0;
3436         char **list;
3437         char *p1, *p2, *p3;
3438
3439         /* create list of variable values */
3440         list = xmalloc(sizeof(*list));
3441         for (i = 0; inp[i]; i++) {
3442                 p3 = insert_var_value(inp[i]);
3443                 p1 = p3;
3444                 while (*p1) {
3445                         if ((*p1 == ' ')) {
3446                                 p1++;
3447                                 continue;
3448                         }
3449                         if ((p2 = strchr(p1, ' '))) {
3450                                 len = p2 - p1;
3451                         } else {
3452                                 len = strlen(p1);
3453                                 p2 = p1 + len;
3454                         }
3455                         /* we use n + 2 in realloc for list,because we add
3456                          * new element and then we will add NULL element */
3457                         list = xrealloc(list, sizeof(*list) * (n + 2));
3458                         list[n] = xmalloc(2 + name_len + len);
3459                         strcpy(list[n], name);
3460                         strcat(list[n], "=");
3461                         strncat(list[n], p1, len);
3462                         list[n++][name_len + len + 1] = '\0';
3463                         p1 = p2;
3464                 }
3465                 if (p3 != inp[i]) free(p3);
3466         }
3467         list[n] = NULL;
3468         return list;
3469 }
3470
3471 /* Make new string for parser */
3472 static char * make_string(char ** inp)
3473 {
3474         char *p;
3475         char *str = NULL;
3476         int n;
3477         int len = 2;
3478
3479         for (n = 0; inp[n]; n++) {
3480                 p = insert_var_value(inp[n]);
3481                 str = xrealloc(str, (len + strlen(p)));
3482                 if (n) {
3483                         strcat(str, " ");
3484                 } else {
3485                         *str = '\0';
3486                 }
3487                 strcat(str, p);
3488                 len = strlen(str) + 3;
3489                 if (p != inp[n]) free(p);
3490         }
3491         len = strlen(str);
3492         *(str + len) = '\n';
3493         *(str + len + 1) = '\0';
3494         return str;
3495 }
3496
3497 #endif /* CFG_HUSH_PARSER */
3498 /****************************************************************************/