kill lash. "lash" builtin still exists, but it runs hush.
authorDenis Vlasenko <vda.linux@googlemail.com>
Fri, 23 Nov 2007 23:28:55 +0000 (23:28 -0000)
committerDenis Vlasenko <vda.linux@googlemail.com>
Fri, 23 Nov 2007 23:28:55 +0000 (23:28 -0000)
TODO
include/applets.h
include/usage.h
shell/Config.in
shell/Kbuild
shell/hush.c
shell/lash.c [deleted file]
shell/lash_unused.c [new file with mode: 0644]

diff --git a/TODO b/TODO
index 10ed7e0d53f14600ca2ce86a9accd68652607452..52a4aad11febf3be2bb2d903db739a60ce088804 100644 (file)
--- a/TODO
+++ b/TODO
@@ -22,12 +22,9 @@ Rob Landley <rob@landley.net>:
     The command shell situation is a big mess.  We have three or four different
     shells that don't really share any code, and the "standalone shell" doesn't
     work all that well (especially not in a chroot environment), due to apps not
-    being reentrant.  I'm writing a new shell (bbsh) to unify the various
-    shells and configurably add the minimal set of bash features people
-    actually use.  The hardest part is it has to configure down as small as
-    lash while providing lash's features.  The rest is easy in comparison.
-  bzip2
-    Compression-side support.
+    being reentrant.
+    lash is phased out. hush can be configured down to be nearly as small,
+    but less buggy :)
   init
     General cleanup (should use ENABLE_FEATURE_INIT_SYSLOG and ENABLE_FEATURE_INIT_DEBUG).
   depmod
@@ -35,8 +32,6 @@ Rob Landley <rob@landley.net>:
     use of the depmod.pl (perl is to bloated for most embedded setups) and or orig
     modutils. The orig depmod is rather pointless to have to add to a firmware image
     in when we already have a insmod/rmmod and friends.
-  Unify base64 handling.
-    [done]
   Do a SUSv3 audit
     Look at the full Single Unix Specification version 3 (available online at
     "http://www.opengroup.org/onlinepubs/009695399/nfindex.html") and
index 757fa4a25c73a342a42592697da1e5d06c7a2ddf..8fdf1a241784d0c140bd197723e8065e340a214a 100644 (file)
@@ -312,7 +312,6 @@ USE_SETSID(APPLET(setsid, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
 USE_SETUIDGID(APPLET_ODDNAME(setuidgid, chpst, _BB_DIR_USR_BIN, _BB_SUID_NEVER, setuidgid))
 USE_FEATURE_SH_IS_ASH(APPLET_NOUSAGE(sh, ash, _BB_DIR_BIN, _BB_SUID_NEVER))
 USE_FEATURE_SH_IS_HUSH(APPLET_NOUSAGE(sh, hush, _BB_DIR_BIN, _BB_SUID_NEVER))
-USE_FEATURE_SH_IS_LASH(APPLET_NOUSAGE(sh, lash, _BB_DIR_BIN, _BB_SUID_NEVER))
 USE_FEATURE_SH_IS_MSH(APPLET_NOUSAGE(sh, msh, _BB_DIR_BIN, _BB_SUID_NEVER))
 USE_SHA1SUM(APPLET_ODDNAME(sha1sum, md5_sha1_sum, _BB_DIR_USR_BIN, _BB_SUID_NEVER, sha1sum))
 USE_SLATTACH(APPLET(slattach, _BB_DIR_SBIN, _BB_SUID_NEVER))
index 82a17578ae44ccb3fc35ddc3528c38ccb1b6e3de..d910e2bf6938e7f5a90bd4170e3bedd66cc6f86b 100644 (file)
@@ -3194,15 +3194,7 @@ USE_FEATURE_RUN_PARTS_FANCY("\n  -l      Prints names of all matching files even when
        "[FILE]...\n" \
        "or: sh -c command [args]..."
 #define lash_full_usage \
-       "The BusyBox LAme SHell (command interpreter)"
-#define lash_notes_usage \
-       "This command does not yet have proper documentation.\n\n" \
-       "Use lash just as you would use any other shell. It properly handles pipes,\n" \
-       "redirects, job control, can be used as the shell for scripts, and has a\n" \
-       "sufficient set of builtins to do what is needed. It does not (yet) support\n" \
-       "Bourne Shell syntax. If you need things like \"if-then-else\", \"while\", and such\n" \
-       "use ash or bash. If you just need a very simple and extremely small shell,\n" \
-       "this will do the job."
+       "lash is deprecated, please use hush"
 
 #define last_trivial_usage \
        ""
index 312583e875bf9e70c8d0c4fe6004ef1fbba40797..9328c910239bab753fa89141795d5c5263cc4717 100644 (file)
@@ -20,9 +20,9 @@ config FEATURE_SH_IS_HUSH
        select HUSH
        bool "hush"
 
-config FEATURE_SH_IS_LASH
-       select LASH
-       bool "lash"
+####config FEATURE_SH_IS_LASH
+####   select LASH
+####   bool "lash"
 
 config FEATURE_SH_IS_MSH
        select MSH
@@ -229,16 +229,9 @@ config HUSH_LOOPS
 config LASH
        bool "lash"
        default n
-       select TRUE
-       select FALSE
-       select TEST
+       select HUSH
        help
-         lash is the very smallest shell (adds just 10k) and it is quite
-         usable as a command prompt, but it is not suitable for any but the
-         most trivial scripting (such as an initrd that calls insmod a few
-         times) since it does not understand any Bourne shell grammar.  It
-         does handle pipes, redirects, and job control though.  Adding in
-         command editing makes it a very nice lightweight command prompt.
+         lash is deprecated and will be removed, please migrate to hush.
 
 
 config MSH
index 944eaff51ea859f322a2375b1fe5b62e2f8e9963..36a8ffd3a2199518d8e5f4d9a7867ffd64ebe048 100644 (file)
@@ -7,7 +7,6 @@
 lib-y:=
 lib-$(CONFIG_ASH)  += ash.o
 lib-$(CONFIG_HUSH) += hush.o
-lib-$(CONFIG_LASH) += lash.o
 lib-$(CONFIG_MSH)  += msh.o
 
 lib-$(CONFIG_CTTYHACK) += cttyhack.o
index 6bf4d1d19021cb6259ddaff061656ec8555c7991..b3c77aa14035f1bdd1915f149a88ea7bd0fa41a0 100644 (file)
@@ -3925,3 +3925,13 @@ int hush_main(int argc, char **argv)
 #endif
        hush_exit(opt ? opt : last_return_code);
 }
+
+
+#if ENABLE_LASH
+int lash_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int lash_main(int argc, char **argv)
+{
+       //bb_error_msg("lash is deprecated, please use hush instead");
+       return hush_main(argc, argv);
+}
+#endif
diff --git a/shell/lash.c b/shell/lash.c
deleted file mode 100644 (file)
index 781dfdb..0000000
+++ /dev/null
@@ -1,1570 +0,0 @@
-/* vi: set sw=4 ts=4: */
-/*
- * lash -- the BusyBox Lame-Ass SHell
- *
- * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
- *
- * Based in part on ladsh.c by Michael K. Johnson and Erik W. Troan, which is
- * under the following liberal license: "We have placed this source code in the
- * public domain. Use it in any project, free or commercial."
- *
- * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
- */
-
-/* This shell's parsing engine is officially at a dead-end.  Future
- * work shell work should be done using hush, msh, or ash.  This is
- * still a very useful, small shell -- it just don't need any more
- * features beyond what it already has...
- */
-
-//For debugging/development on the shell only...
-//#define DEBUG_SHELL
-
-#include <getopt.h>
-#include <glob.h>
-
-#include "busybox.h" /* for struct bb_applet */
-
-#define expand_t       glob_t
-
-/* Always enable for the moment... */
-#define CONFIG_LASH_PIPE_N_REDIRECTS
-#define CONFIG_LASH_JOB_CONTROL
-#define ENABLE_LASH_PIPE_N_REDIRECTS 1
-#define ENABLE_LASH_JOB_CONTROL      1
-
-
-enum { MAX_READ = 128 }; /* size of input buffer for 'read' builtin */
-#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
-
-
-#if ENABLE_LASH_PIPE_N_REDIRECTS
-enum redir_type { REDIRECT_INPUT, REDIRECT_OVERWRITE,
-       REDIRECT_APPEND
-};
-#endif
-
-enum {
-       DEFAULT_CONTEXT = 0x1,
-       IF_TRUE_CONTEXT = 0x2,
-       IF_FALSE_CONTEXT = 0x4,
-       THEN_EXP_CONTEXT = 0x8,
-       ELSE_EXP_CONTEXT = 0x10
-};
-
-#define LASH_OPT_DONE (1)
-#define LASH_OPT_SAW_QUOTE (2)
-
-#if ENABLE_LASH_PIPE_N_REDIRECTS
-struct redir_struct {
-       enum redir_type type;   /* type of redirection */
-       int fd;                                         /* file descriptor being redirected */
-       char *filename;                         /* file to redirect fd to */
-};
-#endif
-
-struct child_prog {
-       pid_t pid;                                      /* 0 if exited */
-       char **argv;                            /* program name and arguments */
-       int num_redirects;                      /* elements in redirection array */
-       int is_stopped;                         /* is the program currently running? */
-       struct job *family;                     /* pointer back to the child's parent job */
-#if ENABLE_LASH_PIPE_N_REDIRECTS
-       struct redir_struct *redirects; /* I/O redirects */
-#endif
-};
-
-struct jobset {
-       struct job *head;                       /* head of list of running jobs */
-       struct job *fg;                         /* current foreground job */
-};
-
-struct job {
-       int jobid;                                      /* job number */
-       int num_progs;                          /* total number of programs in job */
-       int running_progs;                      /* number of programs running */
-       char *text;                                     /* name of job */
-       char *cmdbuf;                           /* buffer various argv's point into */
-       pid_t pgrp;                                     /* process group ID for the job */
-       struct child_prog *progs;       /* array of programs in job */
-       struct job *next;                       /* to track background commands */
-       int stopped_progs;                      /* number of programs alive, but stopped */
-       unsigned int job_context;       /* bitmask defining current context */
-       struct jobset *job_list;
-};
-
-struct built_in_command {
-       const char *cmd;   /* name */
-       const char *descr; /* description */
-       int (*function) (struct child_prog *);  /* function ptr */
-};
-
-/* function prototypes for builtins */
-static int builtin_cd(struct child_prog *cmd);
-static int builtin_exec(struct child_prog *cmd);
-static int builtin_exit(struct child_prog *cmd);
-static int builtin_fg_bg(struct child_prog *cmd);
-static int builtin_help(struct child_prog *cmd);
-static int builtin_jobs(struct child_prog *dummy);
-static int builtin_pwd(struct child_prog *dummy);
-static int builtin_export(struct child_prog *cmd);
-static int builtin_source(struct child_prog *cmd);
-static int builtin_unset(struct child_prog *cmd);
-static int builtin_read(struct child_prog *cmd);
-
-
-/* function prototypes for shell stuff */
-static void checkjobs(struct jobset *job_list);
-static void remove_job(struct jobset *j_list, struct job *job);
-static int get_command_bufsiz(FILE * source, char *command);
-static int parse_command(char **command_ptr, struct job *job, int *inbg);
-static int run_command(struct job *newjob, int inbg, int outpipe[2]);
-static int pseudo_exec(struct child_prog *cmd) ATTRIBUTE_NORETURN;
-static int busy_loop(FILE * input);
-
-
-/* Table of built-in functions (these are non-forking builtins, meaning they
- * can change global variables in the parent shell process but they will not
- * work with pipes and redirects; 'unset foo | whatever' will not work) */
-static const struct built_in_command bltins[] = {
-       {"bg"    , "Resume a job in the background", builtin_fg_bg},
-       {"cd"    , "Change working directory", builtin_cd},
-       {"exec"  , "Exec command, replacing this shell with the exec'd process", builtin_exec},
-       {"exit"  , "Exit from shell()", builtin_exit},
-       {"fg"    , "Bring job into the foreground", builtin_fg_bg},
-       {"jobs"  , "Lists the active jobs", builtin_jobs},
-       {"export", "Set environment variable", builtin_export},
-       {"unset" , "Unset environment variable", builtin_unset},
-       {"read"  , "Input environment variable", builtin_read},
-       {"."     , "Source-in and run commands in a file", builtin_source},
-       /* These were "forked applets", but distinction was nuked */
-       /* Original comment retained: */
-       /* Table of forking built-in functions (things that fork cannot change global
-        * variables in the parent process, such as the current working directory) */
-       {"pwd"   , "Print current directory", builtin_pwd},
-       {"help"  , "List shell built-in commands", builtin_help},
-       /* to do: add ulimit */
-};
-
-
-#define VEC_LAST(v) v[ARRAY_SIZE(v)-1]
-
-
-static int shell_context;  /* Type prompt trigger (PS1 or PS2) */
-
-
-/* Globals that are static to this file */
-static char *cwd;
-static char *local_pending_command;
-static struct jobset job_list = { NULL, NULL };
-static int global_argc;
-static char **global_argv;
-static llist_t *close_me_list;
-static int last_return_code;
-static int last_bg_pid;
-static unsigned int last_jobid;
-static int shell_terminal;
-static const char *PS1;
-static const char *PS2 = "> ";
-
-
-#ifdef DEBUG_SHELL
-static inline void debug_printf(const char *format, ...)
-{
-       va_list args;
-       va_start(args, format);
-       vfprintf(stderr, format, args);
-       va_end(args);
-}
-#else
-static inline void debug_printf(const char ATTRIBUTE_UNUSED *format, ...) { }
-#endif
-
-/*
-       Most builtins need access to the struct child_prog that has
-       their arguments, previously coded as cmd->progs[0].  That coding
-       can exhibit a bug, if the builtin is not the first command in
-       a pipeline: "echo foo | exec sort" will attempt to exec foo.
-
-builtin   previous use      notes
------- -----------------  ---------
-cd      cmd->progs[0]
-exec    cmd->progs[0]  squashed bug: didn't look for applets or forking builtins
-exit    cmd->progs[0]
-fg_bg   cmd->progs[0], job_list->head, job_list->fg
-help    0
-jobs    job_list->head
-pwd     0
-export  cmd->progs[0]
-source  cmd->progs[0]
-unset   cmd->progs[0]
-read    cmd->progs[0]
-
-I added "struct job *family;" to struct child_prog,
-and switched API to builtin_foo(struct child_prog *child);
-So   cmd->text        becomes  child->family->text
-     cmd->job_context  becomes  child->family->job_context
-     cmd->progs[0]    becomes  *child
-     job_list          becomes  child->family->job_list
- */
-
-
-static void update_cwd(void)
-{
-       cwd = xrealloc_getcwd_or_warn(cwd);
-       if (!cwd)
-               cwd = xstrdup(bb_msg_unknown);
-}
-
-/* built-in 'cd <path>' handler */
-static int builtin_cd(struct child_prog *child)
-{
-       char *newdir;
-
-       if (child->argv[1] == NULL)
-               newdir = getenv("HOME");
-       else
-               newdir = child->argv[1];
-       if (chdir(newdir)) {
-               bb_perror_msg("cd: %s", newdir);
-               return EXIT_FAILURE;
-       }
-       update_cwd();
-       return EXIT_SUCCESS;
-}
-
-/* built-in 'exec' handler */
-static int builtin_exec(struct child_prog *child)
-{
-       if (child->argv[1] == NULL)
-               return EXIT_SUCCESS;   /* Really? */
-       child->argv++;
-       while (close_me_list)
-               close((long)llist_pop(&close_me_list));
-       pseudo_exec(child);
-       /* never returns */
-}
-
-/* built-in 'exit' handler */
-static int builtin_exit(struct child_prog *child)
-{
-       if (child->argv[1] == NULL)
-               exit(EXIT_SUCCESS);
-
-       exit(atoi(child->argv[1]));
-}
-
-/* built-in 'fg' and 'bg' handler */
-static int builtin_fg_bg(struct child_prog *child)
-{
-       int i, jobnum;
-       struct job *job;
-
-       /* If they gave us no args, assume they want the last backgrounded task */
-       if (!child->argv[1]) {
-               for (job = child->family->job_list->head; job; job = job->next) {
-                       if (job->jobid == last_jobid) {
-                               goto found;
-                       }
-               }
-               bb_error_msg("%s: no current job", child->argv[0]);
-               return EXIT_FAILURE;
-       }
-       if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
-               bb_error_msg(bb_msg_invalid_arg, child->argv[1], child->argv[0]);
-               return EXIT_FAILURE;
-       }
-       for (job = child->family->job_list->head; job; job = job->next) {
-               if (job->jobid == jobnum) {
-                       goto found;
-               }
-       }
-       bb_error_msg("%s: %d: no such job", child->argv[0], jobnum);
-       return EXIT_FAILURE;
- found:
-       if (*child->argv[0] == 'f') {
-               /* Put the job into the foreground.  */
-               tcsetpgrp(shell_terminal, job->pgrp);
-
-               child->family->job_list->fg = job;
-       }
-
-       /* Restart the processes in the job */
-       for (i = 0; i < job->num_progs; i++)
-               job->progs[i].is_stopped = 0;
-
-       job->stopped_progs = 0;
-
-       i = kill(- job->pgrp, SIGCONT);
-       if (i < 0) {
-               if (errno == ESRCH) {
-                       remove_job(&job_list, job);
-               } else {
-                       bb_perror_msg("kill (SIGCONT)");
-               }
-       }
-
-       return EXIT_SUCCESS;
-}
-
-/* built-in 'help' handler */
-static int builtin_help(struct child_prog ATTRIBUTE_UNUSED *dummy)
-{
-       const struct built_in_command *x;
-
-       printf("\nBuilt-in commands:\n"
-              "-------------------\n");
-       for (x = bltins; x <= &VEC_LAST(bltins); x++) {
-               if (x->descr == NULL)
-                       continue;
-               printf("%s\t%s\n", x->cmd, x->descr);
-       }
-       bb_putchar('\n');
-       return EXIT_SUCCESS;
-}
-
-/* built-in 'jobs' handler */
-static int builtin_jobs(struct child_prog *child)
-{
-       struct job *job;
-       const char *status_string;
-
-       for (job = child->family->job_list->head; job; job = job->next) {
-               if (job->running_progs == job->stopped_progs)
-                       status_string = "Stopped";
-               else
-                       status_string = "Running";
-
-               printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
-       }
-       return EXIT_SUCCESS;
-}
-
-
-/* built-in 'pwd' handler */
-static int builtin_pwd(struct child_prog ATTRIBUTE_UNUSED *dummy)
-{
-       update_cwd();
-       puts(cwd);
-       return EXIT_SUCCESS;
-}
-
-/* built-in 'export VAR=value' handler */
-static int builtin_export(struct child_prog *child)
-{
-       int res;
-       char *v = child->argv[1];
-
-       if (v == NULL) {
-               char **e;
-               for (e = environ; *e; e++) {
-                       puts(*e);
-               }
-               return 0;
-       }
-       res = putenv(v);
-       if (res)
-               bb_perror_msg("export");
-#if ENABLE_FEATURE_EDITING_FANCY_PROMPT
-       if (strncmp(v, "PS1=", 4) == 0)
-               PS1 = getenv("PS1");
-#endif
-
-#if ENABLE_LOCALE_SUPPORT
-       // TODO: why getenv? "" would be just as good...
-       if (strncmp(v, "LC_ALL=", 7) == 0)
-               setlocale(LC_ALL, getenv("LC_ALL"));
-       if (strncmp(v, "LC_CTYPE=", 9) == 0)
-               setlocale(LC_CTYPE, getenv("LC_CTYPE"));
-#endif
-
-       return res;
-}
-
-/* built-in 'read VAR' handler */
-static int builtin_read(struct child_prog *child)
-{
-       int res = 0, len;
-       char *s;
-       char string[MAX_READ];
-
-       if (child->argv[1]) {
-               /* argument (VAR) given: put "VAR=" into buffer */
-               safe_strncpy(string, child->argv[1], MAX_READ-1);
-               len = strlen(string);
-               string[len++] = '=';
-               string[len]   = '\0';
-               fgets(&string[len], sizeof(string) - len, stdin);       /* read string */
-               res = strlen(string);
-               if (res > len)
-                       string[--res] = '\0';   /* chomp trailing newline */
-               /*
-               ** string should now contain "VAR=<value>"
-               ** copy it (putenv() won't do that, so we must make sure
-               ** the string resides in a static buffer!)
-               */
-               res = -1;
-               s = strdup(string);
-               if (s)
-                       res = putenv(s);
-               if (res)
-                       bb_perror_msg("read");
-       } else
-               fgets(string, sizeof(string), stdin);
-
-       return res;
-}
-
-/* Built-in '.' handler (read-in and execute commands from file) */
-static int builtin_source(struct child_prog *child)
-{
-       FILE *input;
-       int status;
-
-       input = fopen_or_warn(child->argv[1], "r");
-       if (!input) {
-               return EXIT_FAILURE;
-       }
-
-       llist_add_to(&close_me_list, (void *)(long)fileno(input));
-       /* Now run the file */
-       status = busy_loop(input);
-       fclose(input);
-       llist_pop(&close_me_list);
-       return status;
-}
-
-/* built-in 'unset VAR' handler */
-static int builtin_unset(struct child_prog *child)
-{
-       if (child->argv[1] == NULL) {
-               printf(bb_msg_requires_arg, "unset");
-               return EXIT_FAILURE;
-       }
-       unsetenv(child->argv[1]);
-       return EXIT_SUCCESS;
-}
-
-#if ENABLE_LASH_JOB_CONTROL
-/* free up all memory from a job */
-static void free_job(struct job *cmd)
-{
-       int i;
-       struct jobset *keep;
-
-       for (i = 0; i < cmd->num_progs; i++) {
-               free(cmd->progs[i].argv);
-#if ENABLE_LASH_PIPE_N_REDIRECTS
-               free(cmd->progs[i].redirects);
-#endif
-       }
-       free(cmd->progs);
-       free(cmd->text);
-       free(cmd->cmdbuf);
-       keep = cmd->job_list;
-       memset(cmd, 0, sizeof(struct job));
-       cmd->job_list = keep;
-}
-
-/* remove a job from a jobset */
-static void remove_job(struct jobset *j_list, struct job *job)
-{
-       struct job *prevjob;
-
-       free_job(job);
-       if (job == j_list->head) {
-               j_list->head = job->next;
-       } else {
-               prevjob = j_list->head;
-               while (prevjob->next != job)
-                       prevjob = prevjob->next;
-               prevjob->next = job->next;
-       }
-
-       if (j_list->head)
-               last_jobid = j_list->head->jobid;
-       else
-               last_jobid = 0;
-
-       free(job);
-}
-
-/* Checks to see if any background processes have exited -- if they
-   have, figure out why and see if a job has completed */
-static void checkjobs(struct jobset *j_list)
-{
-       struct job *job;
-       pid_t childpid;
-       int status;
-       int prognum = 0;
-
-       while ((childpid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) {
-               for (job = j_list->head; job; job = job->next) {
-                       prognum = 0;
-                       while (prognum < job->num_progs &&
-                                  job->progs[prognum].pid != childpid) prognum++;
-                       if (prognum < job->num_progs)
-                               break;
-               }
-
-               /* This happens on backticked commands */
-               if (job == NULL)
-                       return;
-
-               if (WIFEXITED(status) || WIFSIGNALED(status)) {
-                       /* child exited */
-                       job->running_progs--;
-                       job->progs[prognum].pid = 0;
-
-                       if (!job->running_progs) {
-                               printf(JOB_STATUS_FORMAT, job->jobid, "Done", job->text);
-                               last_jobid = 0;
-                               remove_job(j_list, job);
-                       }
-               } else {
-                       /* child stopped */
-                       job->stopped_progs++;
-                       job->progs[prognum].is_stopped = 1;
-               }
-       }
-
-       if (childpid == -1 && errno != ECHILD)
-               bb_perror_msg("waitpid");
-}
-#else
-static void checkjobs(struct jobset *j_list)
-{
-}
-static void free_job(struct job *cmd)
-{
-}
-static void remove_job(struct jobset *j_list, struct job *job)
-{
-}
-#endif
-
-#if ENABLE_LASH_PIPE_N_REDIRECTS
-/* squirrel != NULL means we squirrel away copies of stdin, stdout,
- * and stderr if they are redirected. */
-static int setup_redirects(struct child_prog *prog, int squirrel[])
-{
-       int i;
-       int openfd;
-       int mode = O_RDONLY;
-       struct redir_struct *redir = prog->redirects;
-
-       for (i = 0; i < prog->num_redirects; i++, redir++) {
-               switch (redir->type) {
-               case REDIRECT_INPUT:
-                       mode = O_RDONLY;
-                       break;
-               case REDIRECT_OVERWRITE:
-                       mode = O_WRONLY | O_CREAT | O_TRUNC;
-                       break;
-               case REDIRECT_APPEND:
-                       mode = O_WRONLY | O_CREAT | O_APPEND;
-                       break;
-               }
-
-               openfd = open3_or_warn(redir->filename, mode, 0666);
-               if (openfd < 0) {
-                       /* this could get lost if stderr has been redirected, but
-                          bash and ash both lose it as well (though zsh doesn't!) */
-                       return 1;
-               }
-
-               if (openfd != redir->fd) {
-                       if (squirrel && redir->fd < 3) {
-                               squirrel[redir->fd] = dup(redir->fd);
-                               close_on_exec_on(squirrel[redir->fd]);
-                       }
-                       dup2(openfd, redir->fd);
-                       close(openfd);
-               }
-       }
-
-       return 0;
-}
-
-static void restore_redirects(int squirrel[])
-{
-       int i, fd;
-       for (i = 0; i < 3; i++) {
-               fd = squirrel[i];
-               if (fd != -1) {
-                       /* No error checking.  I sure wouldn't know what
-                        * to do with an error if I found one! */
-                       dup2(fd, i);
-                       close(fd);
-               }
-       }
-}
-#else
-static inline int setup_redirects(struct child_prog *prog, int squirrel[])
-{
-       return 0;
-}
-static inline void restore_redirects(int squirrel[])
-{
-}
-#endif
-
-static inline void cmdedit_set_initial_prompt(void)
-{
-#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
-       PS1 = NULL;
-#else
-       PS1 = getenv("PS1");
-       if (PS1 == 0)
-               PS1 = "\\w \\$ ";
-#endif
-}
-
-static inline const char* setup_prompt_string(void)
-{
-#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
-       /* Set up the prompt */
-       if (shell_context == 0) {
-               char *ns;
-               free((char*)PS1);
-               ns = xmalloc(strlen(cwd)+4);
-               sprintf(ns, "%s %c ", cwd, (geteuid() != 0) ? '$': '#');
-               PS1 = ns;
-               return ns;
-       } else {
-               return PS2;
-       }
-#else
-       return (shell_context == 0)? PS1 : PS2;
-#endif
-}
-
-#if ENABLE_FEATURE_EDITING
-static line_input_t *line_input_state;
-#endif
-
-static int get_command_bufsiz(FILE * source, char *command)
-{
-       const char *prompt_str;
-
-       if (source == NULL) {
-               if (local_pending_command) {
-                       /* a command specified (-c option): return it & mark it done */
-                       strncpy(command, local_pending_command, BUFSIZ);
-                       local_pending_command = NULL;
-                       return 0;
-               }
-               return 1;
-       }
-
-       if (source == stdin) {
-               prompt_str = setup_prompt_string();
-
-#if ENABLE_FEATURE_EDITING
-               /*
-               ** enable command line editing only while a command line
-               ** is actually being read; otherwise, we'll end up bequeathing
-               ** atexit() handlers and other unwanted stuff to our
-               ** child processes (rob@sysgo.de)
-               */
-               read_line_input(prompt_str, command, BUFSIZ, line_input_state);
-               return 0;
-#else
-               fputs(prompt_str, stdout);
-#endif
-       }
-
-       if (!fgets(command, BUFSIZ - 2, source)) {
-               if (source == stdin)
-                       bb_putchar('\n');
-               return 1;
-       }
-
-       return 0;
-}
-
-static char * strsep_space(char *string, int * ix)
-{
-       /* Short circuit the trivial case */
-       if (!string || ! string[*ix])
-               return NULL;
-
-       /* Find the end of the token. */
-       while (string[*ix] && !isspace(string[*ix]) ) {
-               (*ix)++;
-       }
-
-       /* Find the end of any whitespace trailing behind
-        * the token and let that be part of the token */
-       while (string[*ix] && (isspace)(string[*ix]) ) {
-               (*ix)++;
-       }
-
-       if (!*ix) {
-               /* Nothing useful was found */
-               return NULL;
-       }
-
-       return xstrndup(string, *ix);
-}
-
-static int expand_arguments(char *command)
-{
-       static const char out_of_space[] ALIGN1 = "out of space during expansion";
-
-       int total_length = 0, length, i, retval, ix = 0;
-       expand_t expand_result;
-       char *tmpcmd, *cmd, *cmd_copy;
-       char *src, *dst, *var;
-       int flags = GLOB_NOCHECK
-#ifdef GLOB_BRACE
-               | GLOB_BRACE
-#endif
-#ifdef GLOB_TILDE
-               | GLOB_TILDE
-#endif
-               ;
-
-       /* get rid of the terminating \n */
-       chomp(command);
-
-       /* Fix up escape sequences to be the Real Thing(tm) */
-       while (command && command[ix]) {
-               if (command[ix] == '\\') {
-                       const char *tmp = command+ix+1;
-                       command[ix] = bb_process_escape_sequence(  &tmp );
-                       memmove(command+ix + 1, tmp, strlen(tmp)+1);
-               }
-               ix++;
-       }
-       /* Use glob and then fixup environment variables and such */
-
-       /* It turns out that glob is very stupid.  We have to feed it one word at a
-        * time since it can't cope with a full string.  Here we convert command
-        * (char*) into cmd (char**, one word per string) */
-
-       /* We need a clean copy, so strsep can mess up the copy while
-        * we write stuff into the original (in a minute) */
-       cmd = cmd_copy = xstrdup(command);
-       *command = '\0';
-       for (ix = 0, tmpcmd = cmd;
-                       (tmpcmd = strsep_space(cmd, &ix)) != NULL; cmd += ix, ix = 0) {
-               if (*tmpcmd == '\0')
-                       break;
-               /* we need to trim() the result for glob! */
-               trim(tmpcmd);
-               retval = glob(tmpcmd, flags, NULL, &expand_result);
-               free(tmpcmd); /* Free mem allocated by strsep_space */
-               if (retval == GLOB_NOSPACE) {
-                       /* Mem may have been allocated... */
-                       globfree(&expand_result);
-                       bb_error_msg(out_of_space);
-                       return FALSE;
-               } else if (retval != 0) {
-                       /* Some other error.  GLOB_NOMATCH shouldn't
-                        * happen because of the GLOB_NOCHECK flag in
-                        * the glob call. */
-                       bb_error_msg("syntax error");
-                       return FALSE;
-               } else {
-                       /* Convert from char** (one word per string) to a simple char*,
-                        * but don't overflow command which is BUFSIZ in length */
-                       for (i = 0; i < expand_result.gl_pathc; i++) {
-                               length = strlen(expand_result.gl_pathv[i]);
-                               if (total_length+length+1 >= BUFSIZ) {
-                                       bb_error_msg(out_of_space);
-                                       return FALSE;
-                               }
-                               strcat(command+total_length, " ");
-                               total_length += 1;
-                               strcat(command+total_length, expand_result.gl_pathv[i]);
-                               total_length += length;
-                       }
-                       globfree(&expand_result);
-               }
-       }
-       free(cmd_copy);
-       trim(command);
-
-       /* Now do the shell variable substitutions which
-        * wordexp can't do for us, namely $? and $! */
-       src = command;
-       while ((dst = strchr(src,'$')) != NULL) {
-               var = NULL;
-               switch (*(dst+1)) {
-                       case '?':
-                               var = itoa(last_return_code);
-                               break;
-                       case '!':
-                               if (last_bg_pid == -1)
-                                       *var = '\0';
-                               else
-                                       var = itoa(last_bg_pid);
-                               break;
-                               /* Everything else like $$, $#, $[0-9], etc. should all be
-                                * expanded by wordexp(), so we can in theory skip that stuff
-                                * here, but just to be on the safe side (i.e., since uClibc
-                                * wordexp doesn't do this stuff yet), lets leave it in for
-                                * now. */
-                       case '$':
-                               var = itoa(getpid());
-                               break;
-                       case '#':
-                               var = itoa(global_argc - 1);
-                               break;
-                       case '0':case '1':case '2':case '3':case '4':
-                       case '5':case '6':case '7':case '8':case '9':
-                               {
-                                       int ixx = *(dst+1)-48+1;
-                                       if (ixx >= global_argc) {
-                                               var = '\0';
-                                       } else {
-                                               var = global_argv[ixx];
-                                       }
-                               }
-                               break;
-
-               }
-               if (var) {
-                       /* a single character construction was found, and
-                        * already handled in the case statement */
-                       src = dst + 2;
-               } else {
-                       /* Looks like an environment variable */
-                       char delim_hold;
-                       int num_skip_chars = 0;
-                       int dstlen = strlen(dst);
-                       /* Is this a ${foo} type variable? */
-                       if (dstlen >= 2 && *(dst+1) == '{') {
-                               src = strchr(dst+1, '}');
-                               num_skip_chars = 1;
-                       } else {
-                               src = dst + 1;
-                               while ((isalnum)(*src) || *src == '_') src++;
-                       }
-                       if (src == NULL) {
-                               src = dst+dstlen;
-                       }
-                       delim_hold = *src;
-                       *src = '\0';  /* temporary */
-                       var = getenv(dst + 1 + num_skip_chars);
-                       *src = delim_hold;
-                       src += num_skip_chars;
-               }
-               if (var == NULL) {
-                       /* Seems we got an un-expandable variable.  So delete it. */
-                       var = (char*)"";
-               }
-               {
-                       int subst_len = strlen(var);
-                       int trail_len = strlen(src);
-                       if (dst+subst_len+trail_len >= command+BUFSIZ) {
-                               bb_error_msg(out_of_space);
-                               return FALSE;
-                       }
-                       /* Move stuff to the end of the string to accommodate
-                        * filling the created gap with the new stuff */
-                       memmove(dst+subst_len, src, trail_len+1);
-                       /* Now copy in the new stuff */
-                       memcpy(dst, var, subst_len);
-                       src = dst+subst_len;
-               }
-       }
-
-       return TRUE;
-}
-
-/* Return cmd->num_progs as 0 if no command is present (e.g. an empty
-   line). If a valid command is found, command_ptr is set to point to
-   the beginning of the next command (if the original command had more
-   then one job associated with it) or NULL if no more commands are
-   present. */
-static int parse_command(char **command_ptr, struct job *job, int *inbg)
-{
-       char *command;
-       char *return_command = NULL;
-       char *src, *buf;
-       int argc_l;
-       int flag;
-       int argv_alloced;
-       char quote = '\0';
-       struct child_prog *prog;
-#if ENABLE_LASH_PIPE_N_REDIRECTS
-       int i;
-       char *chptr;
-#endif
-
-       /* skip leading white space */
-       *command_ptr = skip_whitespace(*command_ptr);
-
-       /* this handles empty lines or leading '#' characters */
-       if (!**command_ptr || (**command_ptr == '#')) {
-               job->num_progs = 0;
-               return 0;
-       }
-
-       *inbg = 0;
-       job->num_progs = 1;
-       job->progs = xmalloc(sizeof(*job->progs));
-
-       /* We set the argv elements to point inside of this string. The
-          memory is freed by free_job(). Allocate twice the original
-          length in case we need to quote every single character.
-
-          Getting clean memory relieves us of the task of NULL
-          terminating things and makes the rest of this look a bit
-          cleaner (though it is, admittedly, a tad less efficient) */
-       job->cmdbuf = command = xzalloc(2*strlen(*command_ptr) + 1);
-       job->text = NULL;
-
-       prog = job->progs;
-       prog->num_redirects = 0;
-       prog->is_stopped = 0;
-       prog->family = job;
-#if ENABLE_LASH_PIPE_N_REDIRECTS
-       prog->redirects = NULL;
-#endif
-
-       argv_alloced = 5;
-       prog->argv = xmalloc(sizeof(*prog->argv) * argv_alloced);
-       prog->argv[0] = job->cmdbuf;
-
-       flag = argc_l = 0;
-       buf = command;
-       src = *command_ptr;
-       while (*src && !(flag & LASH_OPT_DONE)) {
-               if (quote == *src) {
-                       quote = '\0';
-               } else if (quote) {
-                       if (*src == '\\') {
-                               src++;
-                               if (!*src) {
-                                       bb_error_msg("character expected after \\");
-                                       free_job(job);
-                                       return 1;
-                               }
-
-                               /* in shell, "\'" should yield \' */
-                               if (*src != quote) {
-                                       *buf++ = '\\';
-                                       *buf++ = '\\';
-                               }
-                       } else if (*src == '*' || *src == '?' || *src == '[' ||
-                                          *src == ']') *buf++ = '\\';
-                       *buf++ = *src;
-               } else if (isspace(*src)) {
-                       if (*prog->argv[argc_l] || (flag & LASH_OPT_SAW_QUOTE)) {
-                               buf++, argc_l++;
-                               /* +1 here leaves room for the NULL which ends argv */
-                               if ((argc_l + 1) == argv_alloced) {
-                                       argv_alloced += 5;
-                                       prog->argv = xrealloc(prog->argv,
-                                                       sizeof(*prog->argv) * argv_alloced);
-                               }
-                               prog->argv[argc_l] = buf;
-                               flag ^= LASH_OPT_SAW_QUOTE;
-                       }
-               } else
-                       switch (*src) {
-                       case '"':
-                       case '\'':
-                               quote = *src;
-                               flag |= LASH_OPT_SAW_QUOTE;
-                               break;
-
-                       case '#':                       /* comment */
-                               if (*(src-1)== '$')
-                                       *buf++ = *src;
-                               else
-                                       flag |= LASH_OPT_DONE;
-                               break;
-
-#if ENABLE_LASH_PIPE_N_REDIRECTS
-                       case '>':                       /* redirects */
-                       case '<':
-                               i = prog->num_redirects++;
-                               prog->redirects = xrealloc(prog->redirects,
-                                               sizeof(*prog->redirects) * (i + 1));
-
-                               prog->redirects[i].fd = -1;
-                               if (buf != prog->argv[argc_l]) {
-                                       /* the stuff before this character may be the file number
-                                          being redirected */
-                                       prog->redirects[i].fd =
-                                               strtol(prog->argv[argc_l], &chptr, 10);
-
-                                       if (*chptr && *prog->argv[argc_l]) {
-                                               buf++, argc_l++;
-                                               prog->argv[argc_l] = buf;
-                                       }
-                               }
-
-                               if (prog->redirects[i].fd == -1) {
-                                       if (*src == '>')
-                                               prog->redirects[i].fd = 1;
-                                       else
-                                               prog->redirects[i].fd = 0;
-                               }
-
-                               if (*src++ == '>') {
-                                       if (*src == '>')
-                                               prog->redirects[i].type =
-                                                       REDIRECT_APPEND, src++;
-                                       else
-                                               prog->redirects[i].type = REDIRECT_OVERWRITE;
-                               } else {
-                                       prog->redirects[i].type = REDIRECT_INPUT;
-                               }
-
-                               /* This isn't POSIX sh compliant. Oh well. */
-                               chptr = src;
-                               chptr = skip_whitespace(chptr);
-
-                               if (!*chptr) {
-                                       bb_error_msg("file name expected after %c", *(src-1));
-                                       free_job(job);
-                                       job->num_progs = 0;
-                                       return 1;
-                               }
-
-                               prog->redirects[i].filename = buf;
-                               while (*chptr && !isspace(*chptr))
-                                       *buf++ = *chptr++;
-
-                               src = chptr - 1;        /* we src++ later */
-                               prog->argv[argc_l] = ++buf;
-                               break;
-
-                       case '|':                       /* pipe */
-                               /* finish this command */
-                               if (*prog->argv[argc_l] || flag & LASH_OPT_SAW_QUOTE)
-                                       argc_l++;
-                               if (!argc_l) {
-                                       goto empty_command_in_pipe;
-                               }
-                               prog->argv[argc_l] = NULL;
-
-                               /* and start the next */
-                               job->num_progs++;
-                               job->progs = xrealloc(job->progs,
-                                               sizeof(*job->progs) * job->num_progs);
-                               prog = job->progs + (job->num_progs - 1);
-                               prog->num_redirects = 0;
-                               prog->redirects = NULL;
-                               prog->is_stopped = 0;
-                               prog->family = job;
-                               argc_l = 0;
-
-                               argv_alloced = 5;
-                               prog->argv = xmalloc(sizeof(*prog->argv) * argv_alloced);
-                               prog->argv[0] = ++buf;
-
-                               src++;
-                               src = skip_whitespace(src);
-
-                               if (!*src) {
-empty_command_in_pipe:
-                                       bb_error_msg("empty command in pipe");
-                                       free_job(job);
-                                       job->num_progs = 0;
-                                       return 1;
-                               }
-                               src--;                  /* we'll ++ it at the end of the loop */
-
-                               break;
-#endif
-
-#if ENABLE_LASH_JOB_CONTROL
-                       case '&':                       /* background */
-                               *inbg = 1;
-                               /* fallthrough */
-#endif
-                       case ';':                       /* multiple commands */
-                               flag |= LASH_OPT_DONE;
-                               return_command = *command_ptr + (src - *command_ptr) + 1;
-                               break;
-
-                       case '\\':
-                               src++;
-                               if (!*src) {
-                                       bb_error_msg("character expected after \\");
-                                       free_job(job);
-                                       return 1;
-                               }
-                               if (*src == '*' || *src == '[' || *src == ']'
-                                       || *src == '?') *buf++ = '\\';
-                               /* fallthrough */
-                       default:
-                               *buf++ = *src;
-                       }
-
-               src++;
-       }
-
-       if (*prog->argv[argc_l] || flag & LASH_OPT_SAW_QUOTE) {
-               argc_l++;
-       }
-       if (!argc_l) {
-               free_job(job);
-               return 0;
-       }
-       prog->argv[argc_l] = NULL;
-
-       if (!return_command) {
-               job->text = xstrdup(*command_ptr);
-       } else {
-               /* This leaves any trailing spaces, which is a bit sloppy */
-               job->text = xstrndup(*command_ptr, return_command - *command_ptr);
-       }
-
-       *command_ptr = return_command;
-
-       return 0;
-}
-
-/* Run the child_prog, no matter what kind of command it uses.
- */
-static int pseudo_exec(struct child_prog *child)
-{
-       const struct built_in_command *x;
-
-       /* Check if the command matches any of the non-forking builtins.
-        * Depending on context, this might be redundant.  But it's
-        * easier to waste a few CPU cycles than it is to figure out
-        * if this is one of those cases.
-        */
-       /* Check if the command matches any of the forking builtins. */
-       for (x = bltins; x <= &VEC_LAST(bltins); x++) {
-               if (strcmp(child->argv[0], x->cmd) == 0) {
-                       _exit(x->function(child));
-               }
-       }
-
-       /* Check if the command matches any busybox internal
-        * commands ("applets") here.  Following discussions from
-        * November 2000 on busybox@busybox.net, don't use
-        * bb_get_last_path_component_nostrip().  This way explicit
-        * (with slashes) filenames will never be interpreted as an
-        * applet, just like with builtins.  This way the user can
-        * override an applet with an explicit filename reference.
-        * The only downside to this change is that an explicit
-        * /bin/foo invocation will fork and exec /bin/foo, even if
-        * /bin/foo is a symlink to busybox.
-        */
-       if (ENABLE_FEATURE_SH_STANDALONE) {
-               run_applet_and_exit(child->argv[0], child->argv);
-       }
-
-       execvp(child->argv[0], child->argv);
-
-       /* Do not use bb_perror_msg_and_die() here, since we must not
-        * call exit() but should call _exit() instead */
-       bb_simple_perror_msg(child->argv[0]);
-       _exit(EXIT_FAILURE);
-}
-
-static void insert_job(struct job *newjob, int inbg)
-{
-       struct job *thejob;
-       struct jobset *j_list = newjob->job_list;
-
-       /* find the ID for thejob to use */
-       newjob->jobid = 1;
-       for (thejob = j_list->head; thejob; thejob = thejob->next)
-               if (thejob->jobid >= newjob->jobid)
-                       newjob->jobid = thejob->jobid + 1;
-
-       /* add thejob to the list of running jobs */
-       if (!j_list->head) {
-               thejob = j_list->head = xmalloc(sizeof(*thejob));
-       } else {
-               for (thejob = j_list->head; thejob->next; thejob = thejob->next) /* nothing */;
-               thejob->next = xmalloc(sizeof(*thejob));
-               thejob = thejob->next;
-       }
-
-       *thejob = *newjob;   /* physically copy the struct job */
-       thejob->next = NULL;
-       thejob->running_progs = thejob->num_progs;
-       thejob->stopped_progs = 0;
-
-#if ENABLE_LASH_JOB_CONTROL
-       if (inbg) {
-               /* we don't wait for background thejobs to return -- append it
-                  to the list of backgrounded thejobs and leave it alone */
-               printf("[%d] %d\n", thejob->jobid,
-                          newjob->progs[newjob->num_progs - 1].pid);
-               last_jobid = newjob->jobid;
-               last_bg_pid = newjob->progs[newjob->num_progs - 1].pid;
-       } else {
-               newjob->job_list->fg = thejob;
-
-               /* move the new process group into the foreground */
-               /* Ignore errors since child could have already exited */
-               tcsetpgrp(shell_terminal, newjob->pgrp);
-       }
-#endif
-}
-
-static int run_command(struct job *newjob, int inbg, int outpipe[2])
-{
-       /* struct job *thejob; */
-       int i;
-       int nextin, nextout;
-       int pipefds[2];                         /* pipefd[0] is for reading */
-       const struct built_in_command *x;
-       struct child_prog *child;
-
-       nextin = 0;
-       for (i = 0; i < newjob->num_progs; i++) {
-               child = &(newjob->progs[i]);
-
-               nextout = 1;
-               if ((i + 1) < newjob->num_progs) {
-                       xpipe(pipefds);
-                       nextout = pipefds[1];
-               } else if (outpipe[1] != -1) {
-                       nextout = outpipe[1];
-               }
-
-               /* Check if the command matches any non-forking builtins,
-                * but only if this is a simple command.
-                * Non-forking builtins within pipes have to fork anyway,
-                * and are handled in pseudo_exec.  "echo foo | read bar"
-                * is doomed to failure, and doesn't work on bash, either.
-                */
-               if (newjob->num_progs == 1) {
-                       int rcode;
-                       int squirrel[] = {-1, -1, -1};
-
-                       /* Check if the command sets an environment variable. */
-                       if (strchr(child->argv[0], '=') != NULL) {
-                               child->argv[1] = child->argv[0];
-                               return builtin_export(child);
-                       }
-
-                       for (x = bltins; x <= &VEC_LAST(bltins); x++) {
-                               if (strcmp(child->argv[0], x->cmd) == 0) {
-                                       setup_redirects(child, squirrel);
-                                       rcode = x->function(child);
-                                       restore_redirects(squirrel);
-                                       return rcode;
-                               }
-                       }
-#if ENABLE_FEATURE_SH_STANDALONE
-                       {
-                               const struct bb_applet *a = find_applet_by_name(child->argv[i]);
-                               if (a && a->nofork) {
-                                       setup_redirects(child, squirrel);
-                                       rcode = run_nofork_applet(a, child->argv + i);
-                                       restore_redirects(squirrel);
-                                       return rcode;
-                               }
-                       }
-#endif
-               }
-
-#if BB_MMU
-               child->pid = fork();
-#else
-               child->pid = vfork();
-#endif
-               if (!child->pid) {
-                       /* Set the handling for job control signals back to the default.  */
-                       signal(SIGINT, SIG_DFL);
-                       signal(SIGQUIT, SIG_DFL);
-                       signal(SIGTSTP, SIG_DFL);
-                       signal(SIGTTIN, SIG_DFL);
-                       signal(SIGTTOU, SIG_DFL);
-                       signal(SIGCHLD, SIG_DFL);
-
-                       /* Close all open filehandles. */
-                       while (close_me_list)
-                               close((long)llist_pop(&close_me_list));
-
-                       if (outpipe[1] != -1) {
-                               close(outpipe[0]);
-                       }
-                       if (nextin != 0) {
-                               dup2(nextin, 0);
-                               close(nextin);
-                       }
-
-                       if (nextout != 1) {
-                               dup2(nextout, 1);
-                               dup2(nextout, 2);  /* Really? */
-                               close(nextout);
-                               close(pipefds[0]);
-                       }
-
-                       /* explicit redirects override pipes */
-                       setup_redirects(child,NULL);
-
-                       pseudo_exec(child);
-               }
-               if (outpipe[1] != -1) {
-                       close(outpipe[1]);
-               }
-
-               /* put our child in the process group whose leader is the
-                  first process in this pipe */
-               setpgid(child->pid, newjob->progs[0].pid);
-               if (nextin != 0)
-                       close(nextin);
-               if (nextout != 1)
-                       close(nextout);
-
-               /* If there isn't another process, nextin is garbage
-                  but it doesn't matter */
-               nextin = pipefds[0];
-       }
-
-       newjob->pgrp = newjob->progs[0].pid;
-
-       insert_job(newjob, inbg);
-
-       return 0;
-}
-
-static int busy_loop(FILE * input)
-{
-       char *command;
-       char *next_command = NULL;
-       struct job newjob;
-       int i;
-       int inbg = 0;
-       int status;
-#if ENABLE_LASH_JOB_CONTROL
-       pid_t  parent_pgrp;
-       /* save current owner of TTY so we can restore it on exit */
-       parent_pgrp = tcgetpgrp(shell_terminal);
-#endif
-       newjob.job_list = &job_list;
-       newjob.job_context = DEFAULT_CONTEXT;
-
-       command = xzalloc(BUFSIZ);
-
-       while (1) {
-               if (!job_list.fg) {
-                       /* no job is in the foreground */
-
-                       /* see if any background processes have exited */
-                       checkjobs(&job_list);
-
-                       if (!next_command) {
-                               if (get_command_bufsiz(input, command))
-                                       break;
-                               next_command = command;
-                       }
-
-                       if (!expand_arguments(next_command)) {
-                               free(command);
-                               command = xzalloc(BUFSIZ);
-                               next_command = NULL;
-                               continue;
-                       }
-
-                       if (!parse_command(&next_command, &newjob, &inbg) &&
-                               newjob.num_progs) {
-                               int pipefds[2] = { -1, -1 };
-                               debug_printf("job=%p fed to run_command by busy_loop()'\n",
-                                               &newjob);
-                               run_command(&newjob, inbg, pipefds);
-                       }
-                       else {
-                               free(command);
-                               command = xzalloc(BUFSIZ);
-                               next_command = NULL;
-                       }
-               } else {
-                       /* a job is running in the foreground; wait for it */
-                       i = 0;
-                       while (!job_list.fg->progs[i].pid ||
-                                  job_list.fg->progs[i].is_stopped == 1) i++;
-
-                       if (waitpid(job_list.fg->progs[i].pid, &status, WUNTRACED) < 0) {
-                               if (errno != ECHILD) {
-                                       bb_perror_msg_and_die("waitpid(%d)", job_list.fg->progs[i].pid);
-                               }
-                       }
-
-                       if (WIFEXITED(status) || WIFSIGNALED(status)) {
-                               /* the child exited */
-                               job_list.fg->running_progs--;
-                               job_list.fg->progs[i].pid = 0;
-
-                               last_return_code = WEXITSTATUS(status);
-
-                               if (!job_list.fg->running_progs) {
-                                       /* child exited */
-                                       remove_job(&job_list, job_list.fg);
-                                       job_list.fg = NULL;
-                               }
-                       }
-#if ENABLE_LASH_JOB_CONTROL
-                       else {
-                               /* the child was stopped */
-                               job_list.fg->stopped_progs++;
-                               job_list.fg->progs[i].is_stopped = 1;
-
-                               if (job_list.fg->stopped_progs == job_list.fg->running_progs) {
-                                       printf("\n" JOB_STATUS_FORMAT, job_list.fg->jobid,
-                                                  "Stopped", job_list.fg->text);
-                                       job_list.fg = NULL;
-                               }
-                       }
-
-                       if (!job_list.fg) {
-                               /* move the shell to the foreground */
-                               /* suppress messages when run from /linuxrc mag@sysgo.de */
-                               if (tcsetpgrp(shell_terminal, getpgrp()) && errno != ENOTTY)
-                                       bb_perror_msg("tcsetpgrp");
-                       }
-#endif
-               }
-       }
-       free(command);
-
-#if ENABLE_LASH_JOB_CONTROL
-       /* return controlling TTY back to parent process group before exiting */
-       if (tcsetpgrp(shell_terminal, parent_pgrp) && errno != ENOTTY)
-               bb_perror_msg("tcsetpgrp");
-#endif
-
-       /* return exit status if called with "-c" */
-       if (input == NULL && WIFEXITED(status))
-               return WEXITSTATUS(status);
-
-       return 0;
-}
-
-#if ENABLE_FEATURE_CLEAN_UP
-static void free_memory(void)
-{
-       free(cwd);
-
-       if (job_list.fg && !job_list.fg->running_progs) {
-               remove_job(&job_list, job_list.fg);
-       }
-}
-#else
-void free_memory(void);
-#endif
-
-#if ENABLE_LASH_JOB_CONTROL
-/* Make sure we have a controlling tty.  If we get started under a job
- * aware app (like bash for example), make sure we are now in charge so
- * we don't fight over who gets the foreground */
-static void setup_job_control(void)
-{
-       int status;
-       pid_t shell_pgrp;
-
-       /* Loop until we are in the foreground.  */
-       while ((status = tcgetpgrp(shell_terminal)) >= 0) {
-               shell_pgrp = getpgrp();
-               if (status == shell_pgrp) {
-                       break;
-               }
-               kill(- shell_pgrp, SIGTTIN);
-       }
-
-       /* Ignore interactive and job-control signals.  */
-       signal(SIGINT, SIG_IGN);
-       signal(SIGQUIT, SIG_IGN);
-       signal(SIGTSTP, SIG_IGN);
-       signal(SIGTTIN, SIG_IGN);
-       signal(SIGTTOU, SIG_IGN);
-       signal(SIGCHLD, SIG_IGN);
-
-       /* Put ourselves in our own process group.  */
-       setsid();
-       shell_pgrp = getpid();
-       setpgid(shell_pgrp, shell_pgrp);
-
-       /* Grab control of the terminal.  */
-       tcsetpgrp(shell_terminal, shell_pgrp);
-}
-#else
-static inline void setup_job_control(void)
-{
-}
-#endif
-
-int lash_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int lash_main(int argc, char **argv)
-{
-       unsigned opt;
-       FILE *input = stdin;
-
-       global_argc = argc;
-       global_argv = argv;
-
-#if ENABLE_FEATURE_EDITING
-       line_input_state = new_line_input_t(FOR_SHELL);
-#endif
-
-       /* These variables need re-initializing when recursing */
-       last_jobid = 0;
-       close_me_list = NULL;
-       job_list.head = NULL;
-       job_list.fg = NULL;
-       last_return_code = 1;
-
-       if (global_argv[0] && global_argv[0][0] == '-') {
-               FILE *prof_input;
-               prof_input = fopen("/etc/profile", "r");
-               if (prof_input) {
-                       llist_add_to(&close_me_list, (void *)(long)fileno(prof_input));
-                       /* Now run the file */
-                       busy_loop(prof_input);
-                       fclose_if_not_stdin(prof_input);
-                       llist_pop(&close_me_list);
-               }
-       }
-
-       opt = getopt32(argv, "+ic:", &local_pending_command);
-#define LASH_OPT_i (1<<0)
-#define LASH_OPT_c (1<<1)
-       if (opt & LASH_OPT_c) {
-               input = NULL;
-               optind++;
-               global_argv += optind;
-       }
-       /* A shell is interactive if the `-i' flag was given, or if all of
-        * the following conditions are met:
-        *        no -c command
-        *    no arguments remaining or the -s flag given
-        *    standard input is a terminal
-        *    standard output is a terminal
-        *    Refer to Posix.2, the description of the `sh' utility. */
-       if (global_argv[optind] == NULL && input == stdin
-        && isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)
-       ) {
-               opt |= LASH_OPT_i;
-       }
-       setup_job_control();
-       if (opt & LASH_OPT_i) {
-               /* Looks like they want an interactive shell */
-               if (!ENABLE_FEATURE_SH_EXTRA_QUIET) {
-                       printf("\n\n%s built-in shell (lash)\n"
-                                       "Enter 'help' for a list of built-in commands.\n\n",
-                                       bb_banner);
-               }
-       } else if (!local_pending_command && global_argv[optind]) {
-               //printf( "optind=%d  argv[optind]='%s'\n", optind, argv[optind]);
-               input = xfopen(global_argv[optind], "r");
-               /* be lazy, never mark this closed */
-               llist_add_to(&close_me_list, (void *)(long)fileno(input));
-       }
-
-       /* initialize the cwd -- this is never freed...*/
-       update_cwd();
-
-       if (ENABLE_FEATURE_CLEAN_UP) atexit(free_memory);
-
-       if (ENABLE_FEATURE_EDITING) cmdedit_set_initial_prompt();
-       else PS1 = NULL;
-
-       return busy_loop(input);
-}
diff --git a/shell/lash_unused.c b/shell/lash_unused.c
new file mode 100644 (file)
index 0000000..781dfdb
--- /dev/null
@@ -0,0 +1,1570 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * lash -- the BusyBox Lame-Ass SHell
+ *
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ *
+ * Based in part on ladsh.c by Michael K. Johnson and Erik W. Troan, which is
+ * under the following liberal license: "We have placed this source code in the
+ * public domain. Use it in any project, free or commercial."
+ *
+ * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ */
+
+/* This shell's parsing engine is officially at a dead-end.  Future
+ * work shell work should be done using hush, msh, or ash.  This is
+ * still a very useful, small shell -- it just don't need any more
+ * features beyond what it already has...
+ */
+
+//For debugging/development on the shell only...
+//#define DEBUG_SHELL
+
+#include <getopt.h>
+#include <glob.h>
+
+#include "busybox.h" /* for struct bb_applet */
+
+#define expand_t       glob_t
+
+/* Always enable for the moment... */
+#define CONFIG_LASH_PIPE_N_REDIRECTS
+#define CONFIG_LASH_JOB_CONTROL
+#define ENABLE_LASH_PIPE_N_REDIRECTS 1
+#define ENABLE_LASH_JOB_CONTROL      1
+
+
+enum { MAX_READ = 128 }; /* size of input buffer for 'read' builtin */
+#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
+
+
+#if ENABLE_LASH_PIPE_N_REDIRECTS
+enum redir_type { REDIRECT_INPUT, REDIRECT_OVERWRITE,
+       REDIRECT_APPEND
+};
+#endif
+
+enum {
+       DEFAULT_CONTEXT = 0x1,
+       IF_TRUE_CONTEXT = 0x2,
+       IF_FALSE_CONTEXT = 0x4,
+       THEN_EXP_CONTEXT = 0x8,
+       ELSE_EXP_CONTEXT = 0x10
+};
+
+#define LASH_OPT_DONE (1)
+#define LASH_OPT_SAW_QUOTE (2)
+
+#if ENABLE_LASH_PIPE_N_REDIRECTS
+struct redir_struct {
+       enum redir_type type;   /* type of redirection */
+       int fd;                                         /* file descriptor being redirected */
+       char *filename;                         /* file to redirect fd to */
+};
+#endif
+
+struct child_prog {
+       pid_t pid;                                      /* 0 if exited */
+       char **argv;                            /* program name and arguments */
+       int num_redirects;                      /* elements in redirection array */
+       int is_stopped;                         /* is the program currently running? */
+       struct job *family;                     /* pointer back to the child's parent job */
+#if ENABLE_LASH_PIPE_N_REDIRECTS
+       struct redir_struct *redirects; /* I/O redirects */
+#endif
+};
+
+struct jobset {
+       struct job *head;                       /* head of list of running jobs */
+       struct job *fg;                         /* current foreground job */
+};
+
+struct job {
+       int jobid;                                      /* job number */
+       int num_progs;                          /* total number of programs in job */
+       int running_progs;                      /* number of programs running */
+       char *text;                                     /* name of job */
+       char *cmdbuf;                           /* buffer various argv's point into */
+       pid_t pgrp;                                     /* process group ID for the job */
+       struct child_prog *progs;       /* array of programs in job */
+       struct job *next;                       /* to track background commands */
+       int stopped_progs;                      /* number of programs alive, but stopped */
+       unsigned int job_context;       /* bitmask defining current context */
+       struct jobset *job_list;
+};
+
+struct built_in_command {
+       const char *cmd;   /* name */
+       const char *descr; /* description */
+       int (*function) (struct child_prog *);  /* function ptr */
+};
+
+/* function prototypes for builtins */
+static int builtin_cd(struct child_prog *cmd);
+static int builtin_exec(struct child_prog *cmd);
+static int builtin_exit(struct child_prog *cmd);
+static int builtin_fg_bg(struct child_prog *cmd);
+static int builtin_help(struct child_prog *cmd);
+static int builtin_jobs(struct child_prog *dummy);
+static int builtin_pwd(struct child_prog *dummy);
+static int builtin_export(struct child_prog *cmd);
+static int builtin_source(struct child_prog *cmd);
+static int builtin_unset(struct child_prog *cmd);
+static int builtin_read(struct child_prog *cmd);
+
+
+/* function prototypes for shell stuff */
+static void checkjobs(struct jobset *job_list);
+static void remove_job(struct jobset *j_list, struct job *job);
+static int get_command_bufsiz(FILE * source, char *command);
+static int parse_command(char **command_ptr, struct job *job, int *inbg);
+static int run_command(struct job *newjob, int inbg, int outpipe[2]);
+static int pseudo_exec(struct child_prog *cmd) ATTRIBUTE_NORETURN;
+static int busy_loop(FILE * input);
+
+
+/* Table of built-in functions (these are non-forking builtins, meaning they
+ * can change global variables in the parent shell process but they will not
+ * work with pipes and redirects; 'unset foo | whatever' will not work) */
+static const struct built_in_command bltins[] = {
+       {"bg"    , "Resume a job in the background", builtin_fg_bg},
+       {"cd"    , "Change working directory", builtin_cd},
+       {"exec"  , "Exec command, replacing this shell with the exec'd process", builtin_exec},
+       {"exit"  , "Exit from shell()", builtin_exit},
+       {"fg"    , "Bring job into the foreground", builtin_fg_bg},
+       {"jobs"  , "Lists the active jobs", builtin_jobs},
+       {"export", "Set environment variable", builtin_export},
+       {"unset" , "Unset environment variable", builtin_unset},
+       {"read"  , "Input environment variable", builtin_read},
+       {"."     , "Source-in and run commands in a file", builtin_source},
+       /* These were "forked applets", but distinction was nuked */
+       /* Original comment retained: */
+       /* Table of forking built-in functions (things that fork cannot change global
+        * variables in the parent process, such as the current working directory) */
+       {"pwd"   , "Print current directory", builtin_pwd},
+       {"help"  , "List shell built-in commands", builtin_help},
+       /* to do: add ulimit */
+};
+
+
+#define VEC_LAST(v) v[ARRAY_SIZE(v)-1]
+
+
+static int shell_context;  /* Type prompt trigger (PS1 or PS2) */
+
+
+/* Globals that are static to this file */
+static char *cwd;
+static char *local_pending_command;
+static struct jobset job_list = { NULL, NULL };
+static int global_argc;
+static char **global_argv;
+static llist_t *close_me_list;
+static int last_return_code;
+static int last_bg_pid;
+static unsigned int last_jobid;
+static int shell_terminal;
+static const char *PS1;
+static const char *PS2 = "> ";
+
+
+#ifdef DEBUG_SHELL
+static inline void debug_printf(const char *format, ...)
+{
+       va_list args;
+       va_start(args, format);
+       vfprintf(stderr, format, args);
+       va_end(args);
+}
+#else
+static inline void debug_printf(const char ATTRIBUTE_UNUSED *format, ...) { }
+#endif
+
+/*
+       Most builtins need access to the struct child_prog that has
+       their arguments, previously coded as cmd->progs[0].  That coding
+       can exhibit a bug, if the builtin is not the first command in
+       a pipeline: "echo foo | exec sort" will attempt to exec foo.
+
+builtin   previous use      notes
+------ -----------------  ---------
+cd      cmd->progs[0]
+exec    cmd->progs[0]  squashed bug: didn't look for applets or forking builtins
+exit    cmd->progs[0]
+fg_bg   cmd->progs[0], job_list->head, job_list->fg
+help    0
+jobs    job_list->head
+pwd     0
+export  cmd->progs[0]
+source  cmd->progs[0]
+unset   cmd->progs[0]
+read    cmd->progs[0]
+
+I added "struct job *family;" to struct child_prog,
+and switched API to builtin_foo(struct child_prog *child);
+So   cmd->text        becomes  child->family->text
+     cmd->job_context  becomes  child->family->job_context
+     cmd->progs[0]    becomes  *child
+     job_list          becomes  child->family->job_list
+ */
+
+
+static void update_cwd(void)
+{
+       cwd = xrealloc_getcwd_or_warn(cwd);
+       if (!cwd)
+               cwd = xstrdup(bb_msg_unknown);
+}
+
+/* built-in 'cd <path>' handler */
+static int builtin_cd(struct child_prog *child)
+{
+       char *newdir;
+
+       if (child->argv[1] == NULL)
+               newdir = getenv("HOME");
+       else
+               newdir = child->argv[1];
+       if (chdir(newdir)) {
+               bb_perror_msg("cd: %s", newdir);
+               return EXIT_FAILURE;
+       }
+       update_cwd();
+       return EXIT_SUCCESS;
+}
+
+/* built-in 'exec' handler */
+static int builtin_exec(struct child_prog *child)
+{
+       if (child->argv[1] == NULL)
+               return EXIT_SUCCESS;   /* Really? */
+       child->argv++;
+       while (close_me_list)
+               close((long)llist_pop(&close_me_list));
+       pseudo_exec(child);
+       /* never returns */
+}
+
+/* built-in 'exit' handler */
+static int builtin_exit(struct child_prog *child)
+{
+       if (child->argv[1] == NULL)
+               exit(EXIT_SUCCESS);
+
+       exit(atoi(child->argv[1]));
+}
+
+/* built-in 'fg' and 'bg' handler */
+static int builtin_fg_bg(struct child_prog *child)
+{
+       int i, jobnum;
+       struct job *job;
+
+       /* If they gave us no args, assume they want the last backgrounded task */
+       if (!child->argv[1]) {
+               for (job = child->family->job_list->head; job; job = job->next) {
+                       if (job->jobid == last_jobid) {
+                               goto found;
+                       }
+               }
+               bb_error_msg("%s: no current job", child->argv[0]);
+               return EXIT_FAILURE;
+       }
+       if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
+               bb_error_msg(bb_msg_invalid_arg, child->argv[1], child->argv[0]);
+               return EXIT_FAILURE;
+       }
+       for (job = child->family->job_list->head; job; job = job->next) {
+               if (job->jobid == jobnum) {
+                       goto found;
+               }
+       }
+       bb_error_msg("%s: %d: no such job", child->argv[0], jobnum);
+       return EXIT_FAILURE;
+ found:
+       if (*child->argv[0] == 'f') {
+               /* Put the job into the foreground.  */
+               tcsetpgrp(shell_terminal, job->pgrp);
+
+               child->family->job_list->fg = job;
+       }
+
+       /* Restart the processes in the job */
+       for (i = 0; i < job->num_progs; i++)
+               job->progs[i].is_stopped = 0;
+
+       job->stopped_progs = 0;
+
+       i = kill(- job->pgrp, SIGCONT);
+       if (i < 0) {
+               if (errno == ESRCH) {
+                       remove_job(&job_list, job);
+               } else {
+                       bb_perror_msg("kill (SIGCONT)");
+               }
+       }
+
+       return EXIT_SUCCESS;
+}
+
+/* built-in 'help' handler */
+static int builtin_help(struct child_prog ATTRIBUTE_UNUSED *dummy)
+{
+       const struct built_in_command *x;
+
+       printf("\nBuilt-in commands:\n"
+              "-------------------\n");
+       for (x = bltins; x <= &VEC_LAST(bltins); x++) {
+               if (x->descr == NULL)
+                       continue;
+               printf("%s\t%s\n", x->cmd, x->descr);
+       }
+       bb_putchar('\n');
+       return EXIT_SUCCESS;
+}
+
+/* built-in 'jobs' handler */
+static int builtin_jobs(struct child_prog *child)
+{
+       struct job *job;
+       const char *status_string;
+
+       for (job = child->family->job_list->head; job; job = job->next) {
+               if (job->running_progs == job->stopped_progs)
+                       status_string = "Stopped";
+               else
+                       status_string = "Running";
+
+               printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
+       }
+       return EXIT_SUCCESS;
+}
+
+
+/* built-in 'pwd' handler */
+static int builtin_pwd(struct child_prog ATTRIBUTE_UNUSED *dummy)
+{
+       update_cwd();
+       puts(cwd);
+       return EXIT_SUCCESS;
+}
+
+/* built-in 'export VAR=value' handler */
+static int builtin_export(struct child_prog *child)
+{
+       int res;
+       char *v = child->argv[1];
+
+       if (v == NULL) {
+               char **e;
+               for (e = environ; *e; e++) {
+                       puts(*e);
+               }
+               return 0;
+       }
+       res = putenv(v);
+       if (res)
+               bb_perror_msg("export");
+#if ENABLE_FEATURE_EDITING_FANCY_PROMPT
+       if (strncmp(v, "PS1=", 4) == 0)
+               PS1 = getenv("PS1");
+#endif
+
+#if ENABLE_LOCALE_SUPPORT
+       // TODO: why getenv? "" would be just as good...
+       if (strncmp(v, "LC_ALL=", 7) == 0)
+               setlocale(LC_ALL, getenv("LC_ALL"));
+       if (strncmp(v, "LC_CTYPE=", 9) == 0)
+               setlocale(LC_CTYPE, getenv("LC_CTYPE"));
+#endif
+
+       return res;
+}
+
+/* built-in 'read VAR' handler */
+static int builtin_read(struct child_prog *child)
+{
+       int res = 0, len;
+       char *s;
+       char string[MAX_READ];
+
+       if (child->argv[1]) {
+               /* argument (VAR) given: put "VAR=" into buffer */
+               safe_strncpy(string, child->argv[1], MAX_READ-1);
+               len = strlen(string);
+               string[len++] = '=';
+               string[len]   = '\0';
+               fgets(&string[len], sizeof(string) - len, stdin);       /* read string */
+               res = strlen(string);
+               if (res > len)
+                       string[--res] = '\0';   /* chomp trailing newline */
+               /*
+               ** string should now contain "VAR=<value>"
+               ** copy it (putenv() won't do that, so we must make sure
+               ** the string resides in a static buffer!)
+               */
+               res = -1;
+               s = strdup(string);
+               if (s)
+                       res = putenv(s);
+               if (res)
+                       bb_perror_msg("read");
+       } else
+               fgets(string, sizeof(string), stdin);
+
+       return res;
+}
+
+/* Built-in '.' handler (read-in and execute commands from file) */
+static int builtin_source(struct child_prog *child)
+{
+       FILE *input;
+       int status;
+
+       input = fopen_or_warn(child->argv[1], "r");
+       if (!input) {
+               return EXIT_FAILURE;
+       }
+
+       llist_add_to(&close_me_list, (void *)(long)fileno(input));
+       /* Now run the file */
+       status = busy_loop(input);
+       fclose(input);
+       llist_pop(&close_me_list);
+       return status;
+}
+
+/* built-in 'unset VAR' handler */
+static int builtin_unset(struct child_prog *child)
+{
+       if (child->argv[1] == NULL) {
+               printf(bb_msg_requires_arg, "unset");
+               return EXIT_FAILURE;
+       }
+       unsetenv(child->argv[1]);
+       return EXIT_SUCCESS;
+}
+
+#if ENABLE_LASH_JOB_CONTROL
+/* free up all memory from a job */
+static void free_job(struct job *cmd)
+{
+       int i;
+       struct jobset *keep;
+
+       for (i = 0; i < cmd->num_progs; i++) {
+               free(cmd->progs[i].argv);
+#if ENABLE_LASH_PIPE_N_REDIRECTS
+               free(cmd->progs[i].redirects);
+#endif
+       }
+       free(cmd->progs);
+       free(cmd->text);
+       free(cmd->cmdbuf);
+       keep = cmd->job_list;
+       memset(cmd, 0, sizeof(struct job));
+       cmd->job_list = keep;
+}
+
+/* remove a job from a jobset */
+static void remove_job(struct jobset *j_list, struct job *job)
+{
+       struct job *prevjob;
+
+       free_job(job);
+       if (job == j_list->head) {
+               j_list->head = job->next;
+       } else {
+               prevjob = j_list->head;
+               while (prevjob->next != job)
+                       prevjob = prevjob->next;
+               prevjob->next = job->next;
+       }
+
+       if (j_list->head)
+               last_jobid = j_list->head->jobid;
+       else
+               last_jobid = 0;
+
+       free(job);
+}
+
+/* Checks to see if any background processes have exited -- if they
+   have, figure out why and see if a job has completed */
+static void checkjobs(struct jobset *j_list)
+{
+       struct job *job;
+       pid_t childpid;
+       int status;
+       int prognum = 0;
+
+       while ((childpid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) {
+               for (job = j_list->head; job; job = job->next) {
+                       prognum = 0;
+                       while (prognum < job->num_progs &&
+                                  job->progs[prognum].pid != childpid) prognum++;
+                       if (prognum < job->num_progs)
+                               break;
+               }
+
+               /* This happens on backticked commands */
+               if (job == NULL)
+                       return;
+
+               if (WIFEXITED(status) || WIFSIGNALED(status)) {
+                       /* child exited */
+                       job->running_progs--;
+                       job->progs[prognum].pid = 0;
+
+                       if (!job->running_progs) {
+                               printf(JOB_STATUS_FORMAT, job->jobid, "Done", job->text);
+                               last_jobid = 0;
+                               remove_job(j_list, job);
+                       }
+               } else {
+                       /* child stopped */
+                       job->stopped_progs++;
+                       job->progs[prognum].is_stopped = 1;
+               }
+       }
+
+       if (childpid == -1 && errno != ECHILD)
+               bb_perror_msg("waitpid");
+}
+#else
+static void checkjobs(struct jobset *j_list)
+{
+}
+static void free_job(struct job *cmd)
+{
+}
+static void remove_job(struct jobset *j_list, struct job *job)
+{
+}
+#endif
+
+#if ENABLE_LASH_PIPE_N_REDIRECTS
+/* squirrel != NULL means we squirrel away copies of stdin, stdout,
+ * and stderr if they are redirected. */
+static int setup_redirects(struct child_prog *prog, int squirrel[])
+{
+       int i;
+       int openfd;
+       int mode = O_RDONLY;
+       struct redir_struct *redir = prog->redirects;
+
+       for (i = 0; i < prog->num_redirects; i++, redir++) {
+               switch (redir->type) {
+               case REDIRECT_INPUT:
+                       mode = O_RDONLY;
+                       break;
+               case REDIRECT_OVERWRITE:
+                       mode = O_WRONLY | O_CREAT | O_TRUNC;
+                       break;
+               case REDIRECT_APPEND:
+                       mode = O_WRONLY | O_CREAT | O_APPEND;
+                       break;
+               }
+
+               openfd = open3_or_warn(redir->filename, mode, 0666);
+               if (openfd < 0) {
+                       /* this could get lost if stderr has been redirected, but
+                          bash and ash both lose it as well (though zsh doesn't!) */
+                       return 1;
+               }
+
+               if (openfd != redir->fd) {
+                       if (squirrel && redir->fd < 3) {
+                               squirrel[redir->fd] = dup(redir->fd);
+                               close_on_exec_on(squirrel[redir->fd]);
+                       }
+                       dup2(openfd, redir->fd);
+                       close(openfd);
+               }
+       }
+
+       return 0;
+}
+
+static void restore_redirects(int squirrel[])
+{
+       int i, fd;
+       for (i = 0; i < 3; i++) {
+               fd = squirrel[i];
+               if (fd != -1) {
+                       /* No error checking.  I sure wouldn't know what
+                        * to do with an error if I found one! */
+                       dup2(fd, i);
+                       close(fd);
+               }
+       }
+}
+#else
+static inline int setup_redirects(struct child_prog *prog, int squirrel[])
+{
+       return 0;
+}
+static inline void restore_redirects(int squirrel[])
+{
+}
+#endif
+
+static inline void cmdedit_set_initial_prompt(void)
+{
+#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
+       PS1 = NULL;
+#else
+       PS1 = getenv("PS1");
+       if (PS1 == 0)
+               PS1 = "\\w \\$ ";
+#endif
+}
+
+static inline const char* setup_prompt_string(void)
+{
+#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
+       /* Set up the prompt */
+       if (shell_context == 0) {
+               char *ns;
+               free((char*)PS1);
+               ns = xmalloc(strlen(cwd)+4);
+               sprintf(ns, "%s %c ", cwd, (geteuid() != 0) ? '$': '#');
+               PS1 = ns;
+               return ns;
+       } else {
+               return PS2;
+       }
+#else
+       return (shell_context == 0)? PS1 : PS2;
+#endif
+}
+
+#if ENABLE_FEATURE_EDITING
+static line_input_t *line_input_state;
+#endif
+
+static int get_command_bufsiz(FILE * source, char *command)
+{
+       const char *prompt_str;
+
+       if (source == NULL) {
+               if (local_pending_command) {
+                       /* a command specified (-c option): return it & mark it done */
+                       strncpy(command, local_pending_command, BUFSIZ);
+                       local_pending_command = NULL;
+                       return 0;
+               }
+               return 1;
+       }
+
+       if (source == stdin) {
+               prompt_str = setup_prompt_string();
+
+#if ENABLE_FEATURE_EDITING
+               /*
+               ** enable command line editing only while a command line
+               ** is actually being read; otherwise, we'll end up bequeathing
+               ** atexit() handlers and other unwanted stuff to our
+               ** child processes (rob@sysgo.de)
+               */
+               read_line_input(prompt_str, command, BUFSIZ, line_input_state);
+               return 0;
+#else
+               fputs(prompt_str, stdout);
+#endif
+       }
+
+       if (!fgets(command, BUFSIZ - 2, source)) {
+               if (source == stdin)
+                       bb_putchar('\n');
+               return 1;
+       }
+
+       return 0;
+}
+
+static char * strsep_space(char *string, int * ix)
+{
+       /* Short circuit the trivial case */
+       if (!string || ! string[*ix])
+               return NULL;
+
+       /* Find the end of the token. */
+       while (string[*ix] && !isspace(string[*ix]) ) {
+               (*ix)++;
+       }
+
+       /* Find the end of any whitespace trailing behind
+        * the token and let that be part of the token */
+       while (string[*ix] && (isspace)(string[*ix]) ) {
+               (*ix)++;
+       }
+
+       if (!*ix) {
+               /* Nothing useful was found */
+               return NULL;
+       }
+
+       return xstrndup(string, *ix);
+}
+
+static int expand_arguments(char *command)
+{
+       static const char out_of_space[] ALIGN1 = "out of space during expansion";
+
+       int total_length = 0, length, i, retval, ix = 0;
+       expand_t expand_result;
+       char *tmpcmd, *cmd, *cmd_copy;
+       char *src, *dst, *var;
+       int flags = GLOB_NOCHECK
+#ifdef GLOB_BRACE
+               | GLOB_BRACE
+#endif
+#ifdef GLOB_TILDE
+               | GLOB_TILDE
+#endif
+               ;
+
+       /* get rid of the terminating \n */
+       chomp(command);
+
+       /* Fix up escape sequences to be the Real Thing(tm) */
+       while (command && command[ix]) {
+               if (command[ix] == '\\') {
+                       const char *tmp = command+ix+1;
+                       command[ix] = bb_process_escape_sequence(  &tmp );
+                       memmove(command+ix + 1, tmp, strlen(tmp)+1);
+               }
+               ix++;
+       }
+       /* Use glob and then fixup environment variables and such */
+
+       /* It turns out that glob is very stupid.  We have to feed it one word at a
+        * time since it can't cope with a full string.  Here we convert command
+        * (char*) into cmd (char**, one word per string) */
+
+       /* We need a clean copy, so strsep can mess up the copy while
+        * we write stuff into the original (in a minute) */
+       cmd = cmd_copy = xstrdup(command);
+       *command = '\0';
+       for (ix = 0, tmpcmd = cmd;
+                       (tmpcmd = strsep_space(cmd, &ix)) != NULL; cmd += ix, ix = 0) {
+               if (*tmpcmd == '\0')
+                       break;
+               /* we need to trim() the result for glob! */
+               trim(tmpcmd);
+               retval = glob(tmpcmd, flags, NULL, &expand_result);
+               free(tmpcmd); /* Free mem allocated by strsep_space */
+               if (retval == GLOB_NOSPACE) {
+                       /* Mem may have been allocated... */
+                       globfree(&expand_result);
+                       bb_error_msg(out_of_space);
+                       return FALSE;
+               } else if (retval != 0) {
+                       /* Some other error.  GLOB_NOMATCH shouldn't
+                        * happen because of the GLOB_NOCHECK flag in
+                        * the glob call. */
+                       bb_error_msg("syntax error");
+                       return FALSE;
+               } else {
+                       /* Convert from char** (one word per string) to a simple char*,
+                        * but don't overflow command which is BUFSIZ in length */
+                       for (i = 0; i < expand_result.gl_pathc; i++) {
+                               length = strlen(expand_result.gl_pathv[i]);
+                               if (total_length+length+1 >= BUFSIZ) {
+                                       bb_error_msg(out_of_space);
+                                       return FALSE;
+                               }
+                               strcat(command+total_length, " ");
+                               total_length += 1;
+                               strcat(command+total_length, expand_result.gl_pathv[i]);
+                               total_length += length;
+                       }
+                       globfree(&expand_result);
+               }
+       }
+       free(cmd_copy);
+       trim(command);
+
+       /* Now do the shell variable substitutions which
+        * wordexp can't do for us, namely $? and $! */
+       src = command;
+       while ((dst = strchr(src,'$')) != NULL) {
+               var = NULL;
+               switch (*(dst+1)) {
+                       case '?':
+                               var = itoa(last_return_code);
+                               break;
+                       case '!':
+                               if (last_bg_pid == -1)
+                                       *var = '\0';
+                               else
+                                       var = itoa(last_bg_pid);
+                               break;
+                               /* Everything else like $$, $#, $[0-9], etc. should all be
+                                * expanded by wordexp(), so we can in theory skip that stuff
+                                * here, but just to be on the safe side (i.e., since uClibc
+                                * wordexp doesn't do this stuff yet), lets leave it in for
+                                * now. */
+                       case '$':
+                               var = itoa(getpid());
+                               break;
+                       case '#':
+                               var = itoa(global_argc - 1);
+                               break;
+                       case '0':case '1':case '2':case '3':case '4':
+                       case '5':case '6':case '7':case '8':case '9':
+                               {
+                                       int ixx = *(dst+1)-48+1;
+                                       if (ixx >= global_argc) {
+                                               var = '\0';
+                                       } else {
+                                               var = global_argv[ixx];
+                                       }
+                               }
+                               break;
+
+               }
+               if (var) {
+                       /* a single character construction was found, and
+                        * already handled in the case statement */
+                       src = dst + 2;
+               } else {
+                       /* Looks like an environment variable */
+                       char delim_hold;
+                       int num_skip_chars = 0;
+                       int dstlen = strlen(dst);
+                       /* Is this a ${foo} type variable? */
+                       if (dstlen >= 2 && *(dst+1) == '{') {
+                               src = strchr(dst+1, '}');
+                               num_skip_chars = 1;
+                       } else {
+                               src = dst + 1;
+                               while ((isalnum)(*src) || *src == '_') src++;
+                       }
+                       if (src == NULL) {
+                               src = dst+dstlen;
+                       }
+                       delim_hold = *src;
+                       *src = '\0';  /* temporary */
+                       var = getenv(dst + 1 + num_skip_chars);
+                       *src = delim_hold;
+                       src += num_skip_chars;
+               }
+               if (var == NULL) {
+                       /* Seems we got an un-expandable variable.  So delete it. */
+                       var = (char*)"";
+               }
+               {
+                       int subst_len = strlen(var);
+                       int trail_len = strlen(src);
+                       if (dst+subst_len+trail_len >= command+BUFSIZ) {
+                               bb_error_msg(out_of_space);
+                               return FALSE;
+                       }
+                       /* Move stuff to the end of the string to accommodate
+                        * filling the created gap with the new stuff */
+                       memmove(dst+subst_len, src, trail_len+1);
+                       /* Now copy in the new stuff */
+                       memcpy(dst, var, subst_len);
+                       src = dst+subst_len;
+               }
+       }
+
+       return TRUE;
+}
+
+/* Return cmd->num_progs as 0 if no command is present (e.g. an empty
+   line). If a valid command is found, command_ptr is set to point to
+   the beginning of the next command (if the original command had more
+   then one job associated with it) or NULL if no more commands are
+   present. */
+static int parse_command(char **command_ptr, struct job *job, int *inbg)
+{
+       char *command;
+       char *return_command = NULL;
+       char *src, *buf;
+       int argc_l;
+       int flag;
+       int argv_alloced;
+       char quote = '\0';
+       struct child_prog *prog;
+#if ENABLE_LASH_PIPE_N_REDIRECTS
+       int i;
+       char *chptr;
+#endif
+
+       /* skip leading white space */
+       *command_ptr = skip_whitespace(*command_ptr);
+
+       /* this handles empty lines or leading '#' characters */
+       if (!**command_ptr || (**command_ptr == '#')) {
+               job->num_progs = 0;
+               return 0;
+       }
+
+       *inbg = 0;
+       job->num_progs = 1;
+       job->progs = xmalloc(sizeof(*job->progs));
+
+       /* We set the argv elements to point inside of this string. The
+          memory is freed by free_job(). Allocate twice the original
+          length in case we need to quote every single character.
+
+          Getting clean memory relieves us of the task of NULL
+          terminating things and makes the rest of this look a bit
+          cleaner (though it is, admittedly, a tad less efficient) */
+       job->cmdbuf = command = xzalloc(2*strlen(*command_ptr) + 1);
+       job->text = NULL;
+
+       prog = job->progs;
+       prog->num_redirects = 0;
+       prog->is_stopped = 0;
+       prog->family = job;
+#if ENABLE_LASH_PIPE_N_REDIRECTS
+       prog->redirects = NULL;
+#endif
+
+       argv_alloced = 5;
+       prog->argv = xmalloc(sizeof(*prog->argv) * argv_alloced);
+       prog->argv[0] = job->cmdbuf;
+
+       flag = argc_l = 0;
+       buf = command;
+       src = *command_ptr;
+       while (*src && !(flag & LASH_OPT_DONE)) {
+               if (quote == *src) {
+                       quote = '\0';
+               } else if (quote) {
+                       if (*src == '\\') {
+                               src++;
+                               if (!*src) {
+                                       bb_error_msg("character expected after \\");
+                                       free_job(job);
+                                       return 1;
+                               }
+
+                               /* in shell, "\'" should yield \' */
+                               if (*src != quote) {
+                                       *buf++ = '\\';
+                                       *buf++ = '\\';
+                               }
+                       } else if (*src == '*' || *src == '?' || *src == '[' ||
+                                          *src == ']') *buf++ = '\\';
+                       *buf++ = *src;
+               } else if (isspace(*src)) {
+                       if (*prog->argv[argc_l] || (flag & LASH_OPT_SAW_QUOTE)) {
+                               buf++, argc_l++;
+                               /* +1 here leaves room for the NULL which ends argv */
+                               if ((argc_l + 1) == argv_alloced) {
+                                       argv_alloced += 5;
+                                       prog->argv = xrealloc(prog->argv,
+                                                       sizeof(*prog->argv) * argv_alloced);
+                               }
+                               prog->argv[argc_l] = buf;
+                               flag ^= LASH_OPT_SAW_QUOTE;
+                       }
+               } else
+                       switch (*src) {
+                       case '"':
+                       case '\'':
+                               quote = *src;
+                               flag |= LASH_OPT_SAW_QUOTE;
+                               break;
+
+                       case '#':                       /* comment */
+                               if (*(src-1)== '$')
+                                       *buf++ = *src;
+                               else
+                                       flag |= LASH_OPT_DONE;
+                               break;
+
+#if ENABLE_LASH_PIPE_N_REDIRECTS
+                       case '>':                       /* redirects */
+                       case '<':
+                               i = prog->num_redirects++;
+                               prog->redirects = xrealloc(prog->redirects,
+                                               sizeof(*prog->redirects) * (i + 1));
+
+                               prog->redirects[i].fd = -1;
+                               if (buf != prog->argv[argc_l]) {
+                                       /* the stuff before this character may be the file number
+                                          being redirected */
+                                       prog->redirects[i].fd =
+                                               strtol(prog->argv[argc_l], &chptr, 10);
+
+                                       if (*chptr && *prog->argv[argc_l]) {
+                                               buf++, argc_l++;
+                                               prog->argv[argc_l] = buf;
+                                       }
+                               }
+
+                               if (prog->redirects[i].fd == -1) {
+                                       if (*src == '>')
+                                               prog->redirects[i].fd = 1;
+                                       else
+                                               prog->redirects[i].fd = 0;
+                               }
+
+                               if (*src++ == '>') {
+                                       if (*src == '>')
+                                               prog->redirects[i].type =
+                                                       REDIRECT_APPEND, src++;
+                                       else
+                                               prog->redirects[i].type = REDIRECT_OVERWRITE;
+                               } else {
+                                       prog->redirects[i].type = REDIRECT_INPUT;
+                               }
+
+                               /* This isn't POSIX sh compliant. Oh well. */
+                               chptr = src;
+                               chptr = skip_whitespace(chptr);
+
+                               if (!*chptr) {
+                                       bb_error_msg("file name expected after %c", *(src-1));
+                                       free_job(job);
+                                       job->num_progs = 0;
+                                       return 1;
+                               }
+
+                               prog->redirects[i].filename = buf;
+                               while (*chptr && !isspace(*chptr))
+                                       *buf++ = *chptr++;
+
+                               src = chptr - 1;        /* we src++ later */
+                               prog->argv[argc_l] = ++buf;
+                               break;
+
+                       case '|':                       /* pipe */
+                               /* finish this command */
+                               if (*prog->argv[argc_l] || flag & LASH_OPT_SAW_QUOTE)
+                                       argc_l++;
+                               if (!argc_l) {
+                                       goto empty_command_in_pipe;
+                               }
+                               prog->argv[argc_l] = NULL;
+
+                               /* and start the next */
+                               job->num_progs++;
+                               job->progs = xrealloc(job->progs,
+                                               sizeof(*job->progs) * job->num_progs);
+                               prog = job->progs + (job->num_progs - 1);
+                               prog->num_redirects = 0;
+                               prog->redirects = NULL;
+                               prog->is_stopped = 0;
+                               prog->family = job;
+                               argc_l = 0;
+
+                               argv_alloced = 5;
+                               prog->argv = xmalloc(sizeof(*prog->argv) * argv_alloced);
+                               prog->argv[0] = ++buf;
+
+                               src++;
+                               src = skip_whitespace(src);
+
+                               if (!*src) {
+empty_command_in_pipe:
+                                       bb_error_msg("empty command in pipe");
+                                       free_job(job);
+                                       job->num_progs = 0;
+                                       return 1;
+                               }
+                               src--;                  /* we'll ++ it at the end of the loop */
+
+                               break;
+#endif
+
+#if ENABLE_LASH_JOB_CONTROL
+                       case '&':                       /* background */
+                               *inbg = 1;
+                               /* fallthrough */
+#endif
+                       case ';':                       /* multiple commands */
+                               flag |= LASH_OPT_DONE;
+                               return_command = *command_ptr + (src - *command_ptr) + 1;
+                               break;
+
+                       case '\\':
+                               src++;
+                               if (!*src) {
+                                       bb_error_msg("character expected after \\");
+                                       free_job(job);
+                                       return 1;
+                               }
+                               if (*src == '*' || *src == '[' || *src == ']'
+                                       || *src == '?') *buf++ = '\\';
+                               /* fallthrough */
+                       default:
+                               *buf++ = *src;
+                       }
+
+               src++;
+       }
+
+       if (*prog->argv[argc_l] || flag & LASH_OPT_SAW_QUOTE) {
+               argc_l++;
+       }
+       if (!argc_l) {
+               free_job(job);
+               return 0;
+       }
+       prog->argv[argc_l] = NULL;
+
+       if (!return_command) {
+               job->text = xstrdup(*command_ptr);
+       } else {
+               /* This leaves any trailing spaces, which is a bit sloppy */
+               job->text = xstrndup(*command_ptr, return_command - *command_ptr);
+       }
+
+       *command_ptr = return_command;
+
+       return 0;
+}
+
+/* Run the child_prog, no matter what kind of command it uses.
+ */
+static int pseudo_exec(struct child_prog *child)
+{
+       const struct built_in_command *x;
+
+       /* Check if the command matches any of the non-forking builtins.
+        * Depending on context, this might be redundant.  But it's
+        * easier to waste a few CPU cycles than it is to figure out
+        * if this is one of those cases.
+        */
+       /* Check if the command matches any of the forking builtins. */
+       for (x = bltins; x <= &VEC_LAST(bltins); x++) {
+               if (strcmp(child->argv[0], x->cmd) == 0) {
+                       _exit(x->function(child));
+               }
+       }
+
+       /* Check if the command matches any busybox internal
+        * commands ("applets") here.  Following discussions from
+        * November 2000 on busybox@busybox.net, don't use
+        * bb_get_last_path_component_nostrip().  This way explicit
+        * (with slashes) filenames will never be interpreted as an
+        * applet, just like with builtins.  This way the user can
+        * override an applet with an explicit filename reference.
+        * The only downside to this change is that an explicit
+        * /bin/foo invocation will fork and exec /bin/foo, even if
+        * /bin/foo is a symlink to busybox.
+        */
+       if (ENABLE_FEATURE_SH_STANDALONE) {
+               run_applet_and_exit(child->argv[0], child->argv);
+       }
+
+       execvp(child->argv[0], child->argv);
+
+       /* Do not use bb_perror_msg_and_die() here, since we must not
+        * call exit() but should call _exit() instead */
+       bb_simple_perror_msg(child->argv[0]);
+       _exit(EXIT_FAILURE);
+}
+
+static void insert_job(struct job *newjob, int inbg)
+{
+       struct job *thejob;
+       struct jobset *j_list = newjob->job_list;
+
+       /* find the ID for thejob to use */
+       newjob->jobid = 1;
+       for (thejob = j_list->head; thejob; thejob = thejob->next)
+               if (thejob->jobid >= newjob->jobid)
+                       newjob->jobid = thejob->jobid + 1;
+
+       /* add thejob to the list of running jobs */
+       if (!j_list->head) {
+               thejob = j_list->head = xmalloc(sizeof(*thejob));
+       } else {
+               for (thejob = j_list->head; thejob->next; thejob = thejob->next) /* nothing */;
+               thejob->next = xmalloc(sizeof(*thejob));
+               thejob = thejob->next;
+       }
+
+       *thejob = *newjob;   /* physically copy the struct job */
+       thejob->next = NULL;
+       thejob->running_progs = thejob->num_progs;
+       thejob->stopped_progs = 0;
+
+#if ENABLE_LASH_JOB_CONTROL
+       if (inbg) {
+               /* we don't wait for background thejobs to return -- append it
+                  to the list of backgrounded thejobs and leave it alone */
+               printf("[%d] %d\n", thejob->jobid,
+                          newjob->progs[newjob->num_progs - 1].pid);
+               last_jobid = newjob->jobid;
+               last_bg_pid = newjob->progs[newjob->num_progs - 1].pid;
+       } else {
+               newjob->job_list->fg = thejob;
+
+               /* move the new process group into the foreground */
+               /* Ignore errors since child could have already exited */
+               tcsetpgrp(shell_terminal, newjob->pgrp);
+       }
+#endif
+}
+
+static int run_command(struct job *newjob, int inbg, int outpipe[2])
+{
+       /* struct job *thejob; */
+       int i;
+       int nextin, nextout;
+       int pipefds[2];                         /* pipefd[0] is for reading */
+       const struct built_in_command *x;
+       struct child_prog *child;
+
+       nextin = 0;
+       for (i = 0; i < newjob->num_progs; i++) {
+               child = &(newjob->progs[i]);
+
+               nextout = 1;
+               if ((i + 1) < newjob->num_progs) {
+                       xpipe(pipefds);
+                       nextout = pipefds[1];
+               } else if (outpipe[1] != -1) {
+                       nextout = outpipe[1];
+               }
+
+               /* Check if the command matches any non-forking builtins,
+                * but only if this is a simple command.
+                * Non-forking builtins within pipes have to fork anyway,
+                * and are handled in pseudo_exec.  "echo foo | read bar"
+                * is doomed to failure, and doesn't work on bash, either.
+                */
+               if (newjob->num_progs == 1) {
+                       int rcode;
+                       int squirrel[] = {-1, -1, -1};
+
+                       /* Check if the command sets an environment variable. */
+                       if (strchr(child->argv[0], '=') != NULL) {
+                               child->argv[1] = child->argv[0];
+                               return builtin_export(child);
+                       }
+
+                       for (x = bltins; x <= &VEC_LAST(bltins); x++) {
+                               if (strcmp(child->argv[0], x->cmd) == 0) {
+                                       setup_redirects(child, squirrel);
+                                       rcode = x->function(child);
+                                       restore_redirects(squirrel);
+                                       return rcode;
+                               }
+                       }
+#if ENABLE_FEATURE_SH_STANDALONE
+                       {
+                               const struct bb_applet *a = find_applet_by_name(child->argv[i]);
+                               if (a && a->nofork) {
+                                       setup_redirects(child, squirrel);
+                                       rcode = run_nofork_applet(a, child->argv + i);
+                                       restore_redirects(squirrel);
+                                       return rcode;
+                               }
+                       }
+#endif
+               }
+
+#if BB_MMU
+               child->pid = fork();
+#else
+               child->pid = vfork();
+#endif
+               if (!child->pid) {
+                       /* Set the handling for job control signals back to the default.  */
+                       signal(SIGINT, SIG_DFL);
+                       signal(SIGQUIT, SIG_DFL);
+                       signal(SIGTSTP, SIG_DFL);
+                       signal(SIGTTIN, SIG_DFL);
+                       signal(SIGTTOU, SIG_DFL);
+                       signal(SIGCHLD, SIG_DFL);
+
+                       /* Close all open filehandles. */
+                       while (close_me_list)
+                               close((long)llist_pop(&close_me_list));
+
+                       if (outpipe[1] != -1) {
+                               close(outpipe[0]);
+                       }
+                       if (nextin != 0) {
+                               dup2(nextin, 0);
+                               close(nextin);
+                       }
+
+                       if (nextout != 1) {
+                               dup2(nextout, 1);
+                               dup2(nextout, 2);  /* Really? */
+                               close(nextout);
+                               close(pipefds[0]);
+                       }
+
+                       /* explicit redirects override pipes */
+                       setup_redirects(child,NULL);
+
+                       pseudo_exec(child);
+               }
+               if (outpipe[1] != -1) {
+                       close(outpipe[1]);
+               }
+
+               /* put our child in the process group whose leader is the
+                  first process in this pipe */
+               setpgid(child->pid, newjob->progs[0].pid);
+               if (nextin != 0)
+                       close(nextin);
+               if (nextout != 1)
+                       close(nextout);
+
+               /* If there isn't another process, nextin is garbage
+                  but it doesn't matter */
+               nextin = pipefds[0];
+       }
+
+       newjob->pgrp = newjob->progs[0].pid;
+
+       insert_job(newjob, inbg);
+
+       return 0;
+}
+
+static int busy_loop(FILE * input)
+{
+       char *command;
+       char *next_command = NULL;
+       struct job newjob;
+       int i;
+       int inbg = 0;
+       int status;
+#if ENABLE_LASH_JOB_CONTROL
+       pid_t  parent_pgrp;
+       /* save current owner of TTY so we can restore it on exit */
+       parent_pgrp = tcgetpgrp(shell_terminal);
+#endif
+       newjob.job_list = &job_list;
+       newjob.job_context = DEFAULT_CONTEXT;
+
+       command = xzalloc(BUFSIZ);
+
+       while (1) {
+               if (!job_list.fg) {
+                       /* no job is in the foreground */
+
+                       /* see if any background processes have exited */
+                       checkjobs(&job_list);
+
+                       if (!next_command) {
+                               if (get_command_bufsiz(input, command))
+                                       break;
+                               next_command = command;
+                       }
+
+                       if (!expand_arguments(next_command)) {
+                               free(command);
+                               command = xzalloc(BUFSIZ);
+                               next_command = NULL;
+                               continue;
+                       }
+
+                       if (!parse_command(&next_command, &newjob, &inbg) &&
+                               newjob.num_progs) {
+                               int pipefds[2] = { -1, -1 };
+                               debug_printf("job=%p fed to run_command by busy_loop()'\n",
+                                               &newjob);
+                               run_command(&newjob, inbg, pipefds);
+                       }
+                       else {
+                               free(command);
+                               command = xzalloc(BUFSIZ);
+                               next_command = NULL;
+                       }
+               } else {
+                       /* a job is running in the foreground; wait for it */
+                       i = 0;
+                       while (!job_list.fg->progs[i].pid ||
+                                  job_list.fg->progs[i].is_stopped == 1) i++;
+
+                       if (waitpid(job_list.fg->progs[i].pid, &status, WUNTRACED) < 0) {
+                               if (errno != ECHILD) {
+                                       bb_perror_msg_and_die("waitpid(%d)", job_list.fg->progs[i].pid);
+                               }
+                       }
+
+                       if (WIFEXITED(status) || WIFSIGNALED(status)) {
+                               /* the child exited */
+                               job_list.fg->running_progs--;
+                               job_list.fg->progs[i].pid = 0;
+
+                               last_return_code = WEXITSTATUS(status);
+
+                               if (!job_list.fg->running_progs) {
+                                       /* child exited */
+                                       remove_job(&job_list, job_list.fg);
+                                       job_list.fg = NULL;
+                               }
+                       }
+#if ENABLE_LASH_JOB_CONTROL
+                       else {
+                               /* the child was stopped */
+                               job_list.fg->stopped_progs++;
+                               job_list.fg->progs[i].is_stopped = 1;
+
+                               if (job_list.fg->stopped_progs == job_list.fg->running_progs) {
+                                       printf("\n" JOB_STATUS_FORMAT, job_list.fg->jobid,
+                                                  "Stopped", job_list.fg->text);
+                                       job_list.fg = NULL;
+                               }
+                       }
+
+                       if (!job_list.fg) {
+                               /* move the shell to the foreground */
+                               /* suppress messages when run from /linuxrc mag@sysgo.de */
+                               if (tcsetpgrp(shell_terminal, getpgrp()) && errno != ENOTTY)
+                                       bb_perror_msg("tcsetpgrp");
+                       }
+#endif
+               }
+       }
+       free(command);
+
+#if ENABLE_LASH_JOB_CONTROL
+       /* return controlling TTY back to parent process group before exiting */
+       if (tcsetpgrp(shell_terminal, parent_pgrp) && errno != ENOTTY)
+               bb_perror_msg("tcsetpgrp");
+#endif
+
+       /* return exit status if called with "-c" */
+       if (input == NULL && WIFEXITED(status))
+               return WEXITSTATUS(status);
+
+       return 0;
+}
+
+#if ENABLE_FEATURE_CLEAN_UP
+static void free_memory(void)
+{
+       free(cwd);
+
+       if (job_list.fg && !job_list.fg->running_progs) {
+               remove_job(&job_list, job_list.fg);
+       }
+}
+#else
+void free_memory(void);
+#endif
+
+#if ENABLE_LASH_JOB_CONTROL
+/* Make sure we have a controlling tty.  If we get started under a job
+ * aware app (like bash for example), make sure we are now in charge so
+ * we don't fight over who gets the foreground */
+static void setup_job_control(void)
+{
+       int status;
+       pid_t shell_pgrp;
+
+       /* Loop until we are in the foreground.  */
+       while ((status = tcgetpgrp(shell_terminal)) >= 0) {
+               shell_pgrp = getpgrp();
+               if (status == shell_pgrp) {
+                       break;
+               }
+               kill(- shell_pgrp, SIGTTIN);
+       }
+
+       /* Ignore interactive and job-control signals.  */
+       signal(SIGINT, SIG_IGN);
+       signal(SIGQUIT, SIG_IGN);
+       signal(SIGTSTP, SIG_IGN);
+       signal(SIGTTIN, SIG_IGN);
+       signal(SIGTTOU, SIG_IGN);
+       signal(SIGCHLD, SIG_IGN);
+
+       /* Put ourselves in our own process group.  */
+       setsid();
+       shell_pgrp = getpid();
+       setpgid(shell_pgrp, shell_pgrp);
+
+       /* Grab control of the terminal.  */
+       tcsetpgrp(shell_terminal, shell_pgrp);
+}
+#else
+static inline void setup_job_control(void)
+{
+}
+#endif
+
+int lash_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int lash_main(int argc, char **argv)
+{
+       unsigned opt;
+       FILE *input = stdin;
+
+       global_argc = argc;
+       global_argv = argv;
+
+#if ENABLE_FEATURE_EDITING
+       line_input_state = new_line_input_t(FOR_SHELL);
+#endif
+
+       /* These variables need re-initializing when recursing */
+       last_jobid = 0;
+       close_me_list = NULL;
+       job_list.head = NULL;
+       job_list.fg = NULL;
+       last_return_code = 1;
+
+       if (global_argv[0] && global_argv[0][0] == '-') {
+               FILE *prof_input;
+               prof_input = fopen("/etc/profile", "r");
+               if (prof_input) {
+                       llist_add_to(&close_me_list, (void *)(long)fileno(prof_input));
+                       /* Now run the file */
+                       busy_loop(prof_input);
+                       fclose_if_not_stdin(prof_input);
+                       llist_pop(&close_me_list);
+               }
+       }
+
+       opt = getopt32(argv, "+ic:", &local_pending_command);
+#define LASH_OPT_i (1<<0)
+#define LASH_OPT_c (1<<1)
+       if (opt & LASH_OPT_c) {
+               input = NULL;
+               optind++;
+               global_argv += optind;
+       }
+       /* A shell is interactive if the `-i' flag was given, or if all of
+        * the following conditions are met:
+        *        no -c command
+        *    no arguments remaining or the -s flag given
+        *    standard input is a terminal
+        *    standard output is a terminal
+        *    Refer to Posix.2, the description of the `sh' utility. */
+       if (global_argv[optind] == NULL && input == stdin
+        && isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)
+       ) {
+               opt |= LASH_OPT_i;
+       }
+       setup_job_control();
+       if (opt & LASH_OPT_i) {
+               /* Looks like they want an interactive shell */
+               if (!ENABLE_FEATURE_SH_EXTRA_QUIET) {
+                       printf("\n\n%s built-in shell (lash)\n"
+                                       "Enter 'help' for a list of built-in commands.\n\n",
+                                       bb_banner);
+               }
+       } else if (!local_pending_command && global_argv[optind]) {
+               //printf( "optind=%d  argv[optind]='%s'\n", optind, argv[optind]);
+               input = xfopen(global_argv[optind], "r");
+               /* be lazy, never mark this closed */
+               llist_add_to(&close_me_list, (void *)(long)fileno(input));
+       }
+
+       /* initialize the cwd -- this is never freed...*/
+       update_cwd();
+
+       if (ENABLE_FEATURE_CLEAN_UP) atexit(free_memory);
+
+       if (ENABLE_FEATURE_EDITING) cmdedit_set_initial_prompt();
+       else PS1 = NULL;
+
+       return busy_loop(input);
+}