Added new ext fields to IFC
[oweals/u-boot.git] / common / hush.c
1 /*
2  * sh.c -- a prototype Bourne shell grammar parser
3  *      Intended to follow the original Thompson and Ritchie
4  *      "small and simple is beautiful" philosophy, which
5  *      incidentally is a good match to today's BusyBox.
6  *
7  * Copyright (C) 2000,2001  Larry Doolittle  <larry@doolittle.boa.org>
8  *
9  * Credits:
10  *      The parser routines proper are all original material, first
11  *      written Dec 2000 and Jan 2001 by Larry Doolittle.
12  *      The execution engine, the builtins, and much of the underlying
13  *      support has been adapted from busybox-0.49pre's lash,
14  *      which is Copyright (C) 2000 by Lineo, Inc., and
15  *      written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>.
16  *      That, in turn, is based in part on ladsh.c, by Michael K. Johnson and
17  *      Erik W. Troan, which they placed in the public domain.  I don't know
18  *      how much of the Johnson/Troan code has survived the repeated rewrites.
19  * Other credits:
20  *      b_addchr() derived from similar w_addchar function in glibc-2.2
21  *      setup_redirect(), redirect_opt_num(), and big chunks of main()
22  *        and many builtins derived from contributions by Erik Andersen
23  *      miscellaneous bugfixes from Matt Kraai
24  *
25  * There are two big (and related) architecture differences between
26  * this parser and the lash parser.  One is that this version is
27  * actually designed from the ground up to understand nearly all
28  * of the Bourne grammar.  The second, consequential change is that
29  * the parser and input reader have been turned inside out.  Now,
30  * the parser is in control, and asks for input as needed.  The old
31  * way had the input reader in control, and it asked for parsing to
32  * take place as needed.  The new way makes it much easier to properly
33  * handle the recursion implicit in the various substitutions, especially
34  * across continuation lines.
35  *
36  * Bash grammar not implemented: (how many of these were in original sh?)
37  *      $@ (those sure look like weird quoting rules)
38  *      $_
39  *      ! negation operator for pipes
40  *      &> and >& redirection of stdout+stderr
41  *      Brace Expansion
42  *      Tilde Expansion
43  *      fancy forms of Parameter Expansion
44  *      aliases
45  *      Arithmetic Expansion
46  *      <(list) and >(list) Process Substitution
47  *      reserved words: case, esac, select, function
48  *      Here Documents ( << word )
49  *      Functions
50  * Major bugs:
51  *      job handling woefully incomplete and buggy
52  *      reserved word execution woefully incomplete and buggy
53  * to-do:
54  *      port selected bugfixes from post-0.49 busybox lash - done?
55  *      finish implementing reserved words: for, while, until, do, done
56  *      change { and } from special chars to reserved words
57  *      builtins: break, continue, eval, return, set, trap, ulimit
58  *      test magic exec
59  *      handle children going into background
60  *      clean up recognition of null pipes
61  *      check setting of global_argc and global_argv
62  *      control-C handling, probably with longjmp
63  *      follow IFS rules more precisely, including update semantics
64  *      figure out what to do with backslash-newline
65  *      explain why we use signal instead of sigaction
66  *      propagate syntax errors, die on resource errors?
67  *      continuation lines, both explicit and implicit - done?
68  *      memory leak finding and plugging - done?
69  *      more testing, especially quoting rules and redirection
70  *      document how quoting rules not precisely followed for variable assignments
71  *      maybe change map[] to use 2-bit entries
72  *      (eventually) remove all the printf's
73  *
74  * This program is free software; you can redistribute it and/or modify
75  * it under the terms of the GNU General Public License as published by
76  * the Free Software Foundation; either version 2 of the License, or
77  * (at your option) any later version.
78  *
79  * This program is distributed in the hope that it will be useful,
80  * but WITHOUT ANY WARRANTY; without even the implied warranty of
81  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
82  * General Public License for more details.
83  *
84  * You should have received a copy of the GNU General Public License
85  * along with this program; if not, write to the Free Software
86  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
87  */
88 #define __U_BOOT__
89 #ifdef __U_BOOT__
90 #include <malloc.h>         /* malloc, free, realloc*/
91 #include <linux/ctype.h>    /* isalpha, isdigit */
92 #include <common.h>        /* readline */
93 #include <hush.h>
94 #include <command.h>        /* find_cmd */
95 #ifndef CONFIG_SYS_PROMPT_HUSH_PS2
96 #define CONFIG_SYS_PROMPT_HUSH_PS2      "> "
97 #endif
98 #endif
99 #ifndef __U_BOOT__
100 #include <ctype.h>     /* isalpha, isdigit */
101 #include <unistd.h>    /* getpid */
102 #include <stdlib.h>    /* getenv, atoi */
103 #include <string.h>    /* strchr */
104 #include <stdio.h>     /* popen etc. */
105 #include <glob.h>      /* glob, of course */
106 #include <stdarg.h>    /* va_list */
107 #include <errno.h>
108 #include <fcntl.h>
109 #include <getopt.h>    /* should be pretty obvious */
110
111 #include <sys/stat.h>  /* ulimit */
112 #include <sys/types.h>
113 #include <sys/wait.h>
114 #include <signal.h>
115
116 /* #include <dmalloc.h> */
117
118 #if 1
119 #include "busybox.h"
120 #include "cmdedit.h"
121 #else
122 #define applet_name "hush"
123 #include "standalone.h"
124 #define hush_main main
125 #undef CONFIG_FEATURE_SH_FANCY_PROMPT
126 #define BB_BANNER
127 #endif
128 #endif
129 #define SPECIAL_VAR_SYMBOL 03
130 #ifndef __U_BOOT__
131 #define FLAG_EXIT_FROM_LOOP 1
132 #define FLAG_PARSE_SEMICOLON (1 << 1)           /* symbol ';' is special for parser */
133 #define FLAG_REPARSING       (1 << 2)           /* >= 2nd pass */
134
135 #endif
136
137 #ifdef __U_BOOT__
138 DECLARE_GLOBAL_DATA_PTR;
139
140 #define EXIT_SUCCESS 0
141 #define EOF -1
142 #define syntax() syntax_err()
143 #define xstrdup strdup
144 #define error_msg printf
145 #else
146 typedef enum {
147         REDIRECT_INPUT     = 1,
148         REDIRECT_OVERWRITE = 2,
149         REDIRECT_APPEND    = 3,
150         REDIRECT_HEREIS    = 4,
151         REDIRECT_IO        = 5
152 } redir_type;
153
154 /* The descrip member of this structure is only used to make debugging
155  * output pretty */
156 struct {int mode; int default_fd; char *descrip;} redir_table[] = {
157         { 0,                         0, "()" },
158         { O_RDONLY,                  0, "<"  },
159         { O_CREAT|O_TRUNC|O_WRONLY,  1, ">"  },
160         { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
161         { O_RDONLY,                 -1, "<<" },
162         { O_RDWR,                    1, "<>" }
163 };
164 #endif
165
166 typedef enum {
167         PIPE_SEQ = 1,
168         PIPE_AND = 2,
169         PIPE_OR  = 3,
170         PIPE_BG  = 4,
171 } pipe_style;
172
173 /* might eventually control execution */
174 typedef enum {
175         RES_NONE  = 0,
176         RES_IF    = 1,
177         RES_THEN  = 2,
178         RES_ELIF  = 3,
179         RES_ELSE  = 4,
180         RES_FI    = 5,
181         RES_FOR   = 6,
182         RES_WHILE = 7,
183         RES_UNTIL = 8,
184         RES_DO    = 9,
185         RES_DONE  = 10,
186         RES_XXXX  = 11,
187         RES_IN    = 12,
188         RES_SNTX  = 13
189 } reserved_style;
190 #define FLAG_END   (1<<RES_NONE)
191 #define FLAG_IF    (1<<RES_IF)
192 #define FLAG_THEN  (1<<RES_THEN)
193 #define FLAG_ELIF  (1<<RES_ELIF)
194 #define FLAG_ELSE  (1<<RES_ELSE)
195 #define FLAG_FI    (1<<RES_FI)
196 #define FLAG_FOR   (1<<RES_FOR)
197 #define FLAG_WHILE (1<<RES_WHILE)
198 #define FLAG_UNTIL (1<<RES_UNTIL)
199 #define FLAG_DO    (1<<RES_DO)
200 #define FLAG_DONE  (1<<RES_DONE)
201 #define FLAG_IN    (1<<RES_IN)
202 #define FLAG_START (1<<RES_XXXX)
203
204 /* This holds pointers to the various results of parsing */
205 struct p_context {
206         struct child_prog *child;
207         struct pipe *list_head;
208         struct pipe *pipe;
209 #ifndef __U_BOOT__
210         struct redir_struct *pending_redirect;
211 #endif
212         reserved_style w;
213         int old_flag;                           /* for figuring out valid reserved words */
214         struct p_context *stack;
215         int type;                       /* define type of parser : ";$" common or special symbol */
216         /* How about quoting status? */
217 };
218
219 #ifndef __U_BOOT__
220 struct redir_struct {
221         redir_type type;                        /* type of redirection */
222         int fd;                                         /* file descriptor being redirected */
223         int dup;                                        /* -1, or file descriptor being duplicated */
224         struct redir_struct *next;      /* pointer to the next redirect in the list */
225         glob_t word;                            /* *word.gl_pathv is the filename */
226 };
227 #endif
228
229 struct child_prog {
230 #ifndef __U_BOOT__
231         pid_t pid;                                      /* 0 if exited */
232 #endif
233         char **argv;                            /* program name and arguments */
234 #ifdef __U_BOOT__
235         int    argc;                            /* number of program arguments */
236 #endif
237         struct pipe *group;                     /* if non-NULL, first in group or subshell */
238 #ifndef __U_BOOT__
239         int subshell;                           /* flag, non-zero if group must be forked */
240         struct redir_struct *redirects; /* I/O redirections */
241         glob_t glob_result;                     /* result of parameter globbing */
242         int is_stopped;                         /* is the program currently running? */
243         struct pipe *family;            /* pointer back to the child's parent pipe */
244 #endif
245         int sp;                         /* number of SPECIAL_VAR_SYMBOL */
246         int type;
247 };
248
249 struct pipe {
250 #ifndef __U_BOOT__
251         int jobid;                                      /* job number */
252 #endif
253         int num_progs;                          /* total number of programs in job */
254 #ifndef __U_BOOT__
255         int running_progs;                      /* number of programs running */
256         char *text;                                     /* name of job */
257         char *cmdbuf;                           /* buffer various argv's point into */
258         pid_t pgrp;                                     /* process group ID for the job */
259 #endif
260         struct child_prog *progs;       /* array of commands in pipe */
261         struct pipe *next;                      /* to track background commands */
262 #ifndef __U_BOOT__
263         int stopped_progs;                      /* number of programs alive, but stopped */
264         int job_context;                        /* bitmask defining current context */
265 #endif
266         pipe_style followup;            /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
267         reserved_style r_mode;          /* supports if, for, while, until */
268 };
269
270 #ifndef __U_BOOT__
271 struct close_me {
272         int fd;
273         struct close_me *next;
274 };
275 #endif
276
277 struct variables {
278         char *name;
279         char *value;
280         int flg_export;
281         int flg_read_only;
282         struct variables *next;
283 };
284
285 /* globals, connect us to the outside world
286  * the first three support $?, $#, and $1 */
287 #ifndef __U_BOOT__
288 char **global_argv;
289 unsigned int global_argc;
290 #endif
291 unsigned int last_return_code;
292 int nesting_level;
293 #ifndef __U_BOOT__
294 extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
295 #endif
296
297 /* "globals" within this file */
298 static uchar *ifs;
299 static char map[256];
300 #ifndef __U_BOOT__
301 static int fake_mode;
302 static int interactive;
303 static struct close_me *close_me_head;
304 static const char *cwd;
305 static struct pipe *job_list;
306 static unsigned int last_bg_pid;
307 static unsigned int last_jobid;
308 static unsigned int shell_terminal;
309 static char *PS1;
310 static char *PS2;
311 struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
312 struct variables *top_vars = &shell_ver;
313 #else
314 static int flag_repeat = 0;
315 static int do_repeat = 0;
316 static struct variables *top_vars = NULL ;
317 #endif /*__U_BOOT__ */
318
319 #define B_CHUNK (100)
320 #define B_NOSPAC 1
321
322 typedef struct {
323         char *data;
324         int length;
325         int maxlen;
326         int quote;
327         int nonnull;
328 } o_string;
329 #define NULL_O_STRING {NULL,0,0,0,0}
330 /* used for initialization:
331         o_string foo = NULL_O_STRING; */
332
333 /* I can almost use ordinary FILE *.  Is open_memstream() universally
334  * available?  Where is it documented? */
335 struct in_str {
336         const char *p;
337 #ifndef __U_BOOT__
338         char peek_buf[2];
339 #endif
340         int __promptme;
341         int promptmode;
342 #ifndef __U_BOOT__
343         FILE *file;
344 #endif
345         int (*get) (struct in_str *);
346         int (*peek) (struct in_str *);
347 };
348 #define b_getch(input) ((input)->get(input))
349 #define b_peek(input) ((input)->peek(input))
350
351 #ifndef __U_BOOT__
352 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
353
354 struct built_in_command {
355         char *cmd;                                      /* name */
356         char *descr;                            /* description */
357         int (*function) (struct child_prog *);  /* function ptr */
358 };
359 #endif
360
361 /* define DEBUG_SHELL for debugging output (obviously ;-)) */
362 #if 0
363 #define DEBUG_SHELL
364 #endif
365
366 /* This should be in utility.c */
367 #ifdef DEBUG_SHELL
368 #ifndef __U_BOOT__
369 static void debug_printf(const char *format, ...)
370 {
371         va_list args;
372         va_start(args, format);
373         vfprintf(stderr, format, args);
374         va_end(args);
375 }
376 #else
377 #define debug_printf(fmt,args...)       printf (fmt ,##args)
378 #endif
379 #else
380 static inline void debug_printf(const char *format, ...) { }
381 #endif
382 #define final_printf debug_printf
383
384 #ifdef __U_BOOT__
385 static void syntax_err(void) {
386          printf("syntax error\n");
387 }
388 #else
389 static void __syntax(char *file, int line) {
390         error_msg("syntax error %s:%d", file, line);
391 }
392 #define syntax() __syntax(__FILE__, __LINE__)
393 #endif
394
395 #ifdef __U_BOOT__
396 static void *xmalloc(size_t size);
397 static void *xrealloc(void *ptr, size_t size);
398 #else
399 /* Index of subroutines: */
400 /*   function prototypes for builtins */
401 static int builtin_cd(struct child_prog *child);
402 static int builtin_env(struct child_prog *child);
403 static int builtin_eval(struct child_prog *child);
404 static int builtin_exec(struct child_prog *child);
405 static int builtin_exit(struct child_prog *child);
406 static int builtin_export(struct child_prog *child);
407 static int builtin_fg_bg(struct child_prog *child);
408 static int builtin_help(struct child_prog *child);
409 static int builtin_jobs(struct child_prog *child);
410 static int builtin_pwd(struct child_prog *child);
411 static int builtin_read(struct child_prog *child);
412 static int builtin_set(struct child_prog *child);
413 static int builtin_shift(struct child_prog *child);
414 static int builtin_source(struct child_prog *child);
415 static int builtin_umask(struct child_prog *child);
416 static int builtin_unset(struct child_prog *child);
417 static int builtin_not_written(struct child_prog *child);
418 #endif
419 /*   o_string manipulation: */
420 static int b_check_space(o_string *o, int len);
421 static int b_addchr(o_string *o, int ch);
422 static void b_reset(o_string *o);
423 static int b_addqchr(o_string *o, int ch, int quote);
424 #ifndef __U_BOOT__
425 static int b_adduint(o_string *o, unsigned int i);
426 #endif
427 /*  in_str manipulations: */
428 static int static_get(struct in_str *i);
429 static int static_peek(struct in_str *i);
430 static int file_get(struct in_str *i);
431 static int file_peek(struct in_str *i);
432 #ifndef __U_BOOT__
433 static void setup_file_in_str(struct in_str *i, FILE *f);
434 #else
435 static void setup_file_in_str(struct in_str *i);
436 #endif
437 static void setup_string_in_str(struct in_str *i, const char *s);
438 #ifndef __U_BOOT__
439 /*  close_me manipulations: */
440 static void mark_open(int fd);
441 static void mark_closed(int fd);
442 static void close_all(void);
443 #endif
444 /*  "run" the final data structures: */
445 static char *indenter(int i);
446 static int free_pipe_list(struct pipe *head, int indent);
447 static int free_pipe(struct pipe *pi, int indent);
448 /*  really run the final data structures: */
449 #ifndef __U_BOOT__
450 static int setup_redirects(struct child_prog *prog, int squirrel[]);
451 #endif
452 static int run_list_real(struct pipe *pi);
453 #ifndef __U_BOOT__
454 static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
455 #endif
456 static int run_pipe_real(struct pipe *pi);
457 /*   extended glob support: */
458 #ifndef __U_BOOT__
459 static int globhack(const char *src, int flags, glob_t *pglob);
460 static int glob_needed(const char *s);
461 static int xglob(o_string *dest, int flags, glob_t *pglob);
462 #endif
463 /*   variable assignment: */
464 static int is_assignment(const char *s);
465 /*   data structure manipulation: */
466 #ifndef __U_BOOT__
467 static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
468 #endif
469 static void initialize_context(struct p_context *ctx);
470 static int done_word(o_string *dest, struct p_context *ctx);
471 static int done_command(struct p_context *ctx);
472 static int done_pipe(struct p_context *ctx, pipe_style type);
473 /*   primary string parsing: */
474 #ifndef __U_BOOT__
475 static int redirect_dup_num(struct in_str *input);
476 static int redirect_opt_num(o_string *o);
477 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
478 static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
479 #endif
480 static char *lookup_param(char *src);
481 static char *make_string(char **inp);
482 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
483 #ifndef __U_BOOT__
484 static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
485 #endif
486 static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
487 /*   setup: */
488 static int parse_stream_outer(struct in_str *inp, int flag);
489 #ifndef __U_BOOT__
490 static int parse_string_outer(const char *s, int flag);
491 static int parse_file_outer(FILE *f);
492 #endif
493 #ifndef __U_BOOT__
494 /*   job management: */
495 static int checkjobs(struct pipe* fg_pipe);
496 static void insert_bg_job(struct pipe *pi);
497 static void remove_bg_job(struct pipe *pi);
498 #endif
499 /*     local variable support */
500 static char **make_list_in(char **inp, char *name);
501 static char *insert_var_value(char *inp);
502
503 #ifndef __U_BOOT__
504 /* Table of built-in functions.  They can be forked or not, depending on
505  * context: within pipes, they fork.  As simple commands, they do not.
506  * When used in non-forking context, they can change global variables
507  * in the parent shell process.  If forked, of course they can not.
508  * For example, 'unset foo | whatever' will parse and run, but foo will
509  * still be set at the end. */
510 static struct built_in_command bltins[] = {
511         {"bg", "Resume a job in the background", builtin_fg_bg},
512         {"break", "Exit for, while or until loop", builtin_not_written},
513         {"cd", "Change working directory", builtin_cd},
514         {"continue", "Continue for, while or until loop", builtin_not_written},
515         {"env", "Print all environment variables", builtin_env},
516         {"eval", "Construct and run shell command", builtin_eval},
517         {"exec", "Exec command, replacing this shell with the exec'd process",
518                 builtin_exec},
519         {"exit", "Exit from shell()", builtin_exit},
520         {"export", "Set environment variable", builtin_export},
521         {"fg", "Bring job into the foreground", builtin_fg_bg},
522         {"jobs", "Lists the active jobs", builtin_jobs},
523         {"pwd", "Print current directory", builtin_pwd},
524         {"read", "Input environment variable", builtin_read},
525         {"return", "Return from a function", builtin_not_written},
526         {"set", "Set/unset shell local variables", builtin_set},
527         {"shift", "Shift positional parameters", builtin_shift},
528         {"trap", "Trap signals", builtin_not_written},
529         {"ulimit","Controls resource limits", builtin_not_written},
530         {"umask","Sets file creation mask", builtin_umask},
531         {"unset", "Unset environment variable", builtin_unset},
532         {".", "Source-in and run commands in a file", builtin_source},
533         {"help", "List shell built-in commands", builtin_help},
534         {NULL, NULL, NULL}
535 };
536
537 static const char *set_cwd(void)
538 {
539         if(cwd==unknown)
540                 cwd = NULL;     /* xgetcwd(arg) called free(arg) */
541         cwd = xgetcwd((char *)cwd);
542         if (!cwd)
543                 cwd = unknown;
544         return cwd;
545 }
546
547 /* built-in 'eval' handler */
548 static int builtin_eval(struct child_prog *child)
549 {
550         char *str = NULL;
551         int rcode = EXIT_SUCCESS;
552
553         if (child->argv[1]) {
554                 str = make_string(child->argv + 1);
555                 parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
556                                         FLAG_PARSE_SEMICOLON);
557                 free(str);
558                 rcode = last_return_code;
559         }
560         return rcode;
561 }
562
563 /* built-in 'cd <path>' handler */
564 static int builtin_cd(struct child_prog *child)
565 {
566         char *newdir;
567         if (child->argv[1] == NULL)
568                 newdir = getenv("HOME");
569         else
570                 newdir = child->argv[1];
571         if (chdir(newdir)) {
572                 printf("cd: %s: %s\n", newdir, strerror(errno));
573                 return EXIT_FAILURE;
574         }
575         set_cwd();
576         return EXIT_SUCCESS;
577 }
578
579 /* built-in 'env' handler */
580 static int builtin_env(struct child_prog *dummy)
581 {
582         char **e = environ;
583         if (e == NULL) return EXIT_FAILURE;
584         for (; *e; e++) {
585                 puts(*e);
586         }
587         return EXIT_SUCCESS;
588 }
589
590 /* built-in 'exec' handler */
591 static int builtin_exec(struct child_prog *child)
592 {
593         if (child->argv[1] == NULL)
594                 return EXIT_SUCCESS;   /* Really? */
595         child->argv++;
596         pseudo_exec(child);
597         /* never returns */
598 }
599
600 /* built-in 'exit' handler */
601 static int builtin_exit(struct child_prog *child)
602 {
603         if (child->argv[1] == NULL)
604                 exit(last_return_code);
605         exit (atoi(child->argv[1]));
606 }
607
608 /* built-in 'export VAR=value' handler */
609 static int builtin_export(struct child_prog *child)
610 {
611         int res = 0;
612         char *name = child->argv[1];
613
614         if (name == NULL) {
615                 return (builtin_env(child));
616         }
617
618         name = strdup(name);
619
620         if(name) {
621                 char *value = strchr(name, '=');
622
623                 if (!value) {
624                         char *tmp;
625                         /* They are exporting something without an =VALUE */
626
627                         value = get_local_var(name);
628                         if (value) {
629                                 size_t ln = strlen(name);
630
631                                 tmp = realloc(name, ln+strlen(value)+2);
632                                 if(tmp==NULL)
633                                         res = -1;
634                                 else {
635                                         sprintf(tmp+ln, "=%s", value);
636                                         name = tmp;
637                                 }
638                         } else {
639                                 /* bash does not return an error when trying to export
640                                  * an undefined variable.  Do likewise. */
641                                 res = 1;
642                         }
643                 }
644         }
645         if (res<0)
646                 perror_msg("export");
647         else if(res==0)
648                 res = set_local_var(name, 1);
649         else
650                 res = 0;
651         free(name);
652         return res;
653 }
654
655 /* built-in 'fg' and 'bg' handler */
656 static int builtin_fg_bg(struct child_prog *child)
657 {
658         int i, jobnum;
659         struct pipe *pi=NULL;
660
661         if (!interactive)
662                 return EXIT_FAILURE;
663         /* If they gave us no args, assume they want the last backgrounded task */
664         if (!child->argv[1]) {
665                 for (pi = job_list; pi; pi = pi->next) {
666                         if (pi->jobid == last_jobid) {
667                                 break;
668                         }
669                 }
670                 if (!pi) {
671                         error_msg("%s: no current job", child->argv[0]);
672                         return EXIT_FAILURE;
673                 }
674         } else {
675                 if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
676                         error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
677                         return EXIT_FAILURE;
678                 }
679                 for (pi = job_list; pi; pi = pi->next) {
680                         if (pi->jobid == jobnum) {
681                                 break;
682                         }
683                 }
684                 if (!pi) {
685                         error_msg("%s: %d: no such job", child->argv[0], jobnum);
686                         return EXIT_FAILURE;
687                 }
688         }
689
690         if (*child->argv[0] == 'f') {
691                 /* Put the job into the foreground.  */
692                 tcsetpgrp(shell_terminal, pi->pgrp);
693         }
694
695         /* Restart the processes in the job */
696         for (i = 0; i < pi->num_progs; i++)
697                 pi->progs[i].is_stopped = 0;
698
699         if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) {
700                 if (i == ESRCH) {
701                         remove_bg_job(pi);
702                 } else {
703                         perror_msg("kill (SIGCONT)");
704                 }
705         }
706
707         pi->stopped_progs = 0;
708         return EXIT_SUCCESS;
709 }
710
711 /* built-in 'help' handler */
712 static int builtin_help(struct child_prog *dummy)
713 {
714         struct built_in_command *x;
715
716         printf("\nBuilt-in commands:\n");
717         printf("-------------------\n");
718         for (x = bltins; x->cmd; x++) {
719                 if (x->descr==NULL)
720                         continue;
721                 printf("%s\t%s\n", x->cmd, x->descr);
722         }
723         printf("\n\n");
724         return EXIT_SUCCESS;
725 }
726
727 /* built-in 'jobs' handler */
728 static int builtin_jobs(struct child_prog *child)
729 {
730         struct pipe *job;
731         char *status_string;
732
733         for (job = job_list; job; job = job->next) {
734                 if (job->running_progs == job->stopped_progs)
735                         status_string = "Stopped";
736                 else
737                         status_string = "Running";
738
739                 printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
740         }
741         return EXIT_SUCCESS;
742 }
743
744
745 /* built-in 'pwd' handler */
746 static int builtin_pwd(struct child_prog *dummy)
747 {
748         puts(set_cwd());
749         return EXIT_SUCCESS;
750 }
751
752 /* built-in 'read VAR' handler */
753 static int builtin_read(struct child_prog *child)
754 {
755         int res;
756
757         if (child->argv[1]) {
758                 char string[BUFSIZ];
759                 char *var = 0;
760
761                 string[0] = 0;  /* In case stdin has only EOF */
762                 /* read string */
763                 fgets(string, sizeof(string), stdin);
764                 chomp(string);
765                 var = malloc(strlen(child->argv[1])+strlen(string)+2);
766                 if(var) {
767                         sprintf(var, "%s=%s", child->argv[1], string);
768                         res = set_local_var(var, 0);
769                 } else
770                         res = -1;
771                 if (res)
772                         fprintf(stderr, "read: %m\n");
773                 free(var);      /* So not move up to avoid breaking errno */
774                 return res;
775         } else {
776                 do res=getchar(); while(res!='\n' && res!=EOF);
777                 return 0;
778         }
779 }
780
781 /* built-in 'set VAR=value' handler */
782 static int builtin_set(struct child_prog *child)
783 {
784         char *temp = child->argv[1];
785         struct variables *e;
786
787         if (temp == NULL)
788                 for(e = top_vars; e; e=e->next)
789                         printf("%s=%s\n", e->name, e->value);
790         else
791                 set_local_var(temp, 0);
792
793                 return EXIT_SUCCESS;
794 }
795
796
797 /* Built-in 'shift' handler */
798 static int builtin_shift(struct child_prog *child)
799 {
800         int n=1;
801         if (child->argv[1]) {
802                 n=atoi(child->argv[1]);
803         }
804         if (n>=0 && n<global_argc) {
805                 /* XXX This probably breaks $0 */
806                 global_argc -= n;
807                 global_argv += n;
808                 return EXIT_SUCCESS;
809         } else {
810                 return EXIT_FAILURE;
811         }
812 }
813
814 /* Built-in '.' handler (read-in and execute commands from file) */
815 static int builtin_source(struct child_prog *child)
816 {
817         FILE *input;
818         int status;
819
820         if (child->argv[1] == NULL)
821                 return EXIT_FAILURE;
822
823         /* XXX search through $PATH is missing */
824         input = fopen(child->argv[1], "r");
825         if (!input) {
826                 error_msg("Couldn't open file '%s'", child->argv[1]);
827                 return EXIT_FAILURE;
828         }
829
830         /* Now run the file */
831         /* XXX argv and argc are broken; need to save old global_argv
832          * (pointer only is OK!) on this stack frame,
833          * set global_argv=child->argv+1, recurse, and restore. */
834         mark_open(fileno(input));
835         status = parse_file_outer(input);
836         mark_closed(fileno(input));
837         fclose(input);
838         return (status);
839 }
840
841 static int builtin_umask(struct child_prog *child)
842 {
843         mode_t new_umask;
844         const char *arg = child->argv[1];
845         char *end;
846         if (arg) {
847                 new_umask=strtoul(arg, &end, 8);
848                 if (*end!='\0' || end == arg) {
849                         return EXIT_FAILURE;
850                 }
851         } else {
852                 printf("%.3o\n", (unsigned int) (new_umask=umask(0)));
853         }
854         umask(new_umask);
855         return EXIT_SUCCESS;
856 }
857
858 /* built-in 'unset VAR' handler */
859 static int builtin_unset(struct child_prog *child)
860 {
861         /* bash returned already true */
862         unset_local_var(child->argv[1]);
863         return EXIT_SUCCESS;
864 }
865
866 static int builtin_not_written(struct child_prog *child)
867 {
868         printf("builtin_%s not written\n",child->argv[0]);
869         return EXIT_FAILURE;
870 }
871 #endif
872
873 static int b_check_space(o_string *o, int len)
874 {
875         /* It would be easy to drop a more restrictive policy
876          * in here, such as setting a maximum string length */
877         if (o->length + len > o->maxlen) {
878                 char *old_data = o->data;
879                 /* assert (data == NULL || o->maxlen != 0); */
880                 o->maxlen += max(2*len, B_CHUNK);
881                 o->data = realloc(o->data, 1 + o->maxlen);
882                 if (o->data == NULL) {
883                         free(old_data);
884                 }
885         }
886         return o->data == NULL;
887 }
888
889 static int b_addchr(o_string *o, int ch)
890 {
891         debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
892         if (b_check_space(o, 1)) return B_NOSPAC;
893         o->data[o->length] = ch;
894         o->length++;
895         o->data[o->length] = '\0';
896         return 0;
897 }
898
899 static void b_reset(o_string *o)
900 {
901         o->length = 0;
902         o->nonnull = 0;
903         if (o->data != NULL) *o->data = '\0';
904 }
905
906 static void b_free(o_string *o)
907 {
908         b_reset(o);
909         free(o->data);
910         o->data = NULL;
911         o->maxlen = 0;
912 }
913
914 /* My analysis of quoting semantics tells me that state information
915  * is associated with a destination, not a source.
916  */
917 static int b_addqchr(o_string *o, int ch, int quote)
918 {
919         if (quote && strchr("*?[\\",ch)) {
920                 int rc;
921                 rc = b_addchr(o, '\\');
922                 if (rc) return rc;
923         }
924         return b_addchr(o, ch);
925 }
926
927 #ifndef __U_BOOT__
928 static int b_adduint(o_string *o, unsigned int i)
929 {
930         int r;
931         char *p = simple_itoa(i);
932         /* no escape checking necessary */
933         do r=b_addchr(o, *p++); while (r==0 && *p);
934         return r;
935 }
936 #endif
937
938 static int static_get(struct in_str *i)
939 {
940         int ch = *i->p++;
941         if (ch=='\0') return EOF;
942         return ch;
943 }
944
945 static int static_peek(struct in_str *i)
946 {
947         return *i->p;
948 }
949
950 #ifndef __U_BOOT__
951 static inline void cmdedit_set_initial_prompt(void)
952 {
953 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
954         PS1 = NULL;
955 #else
956         PS1 = getenv("PS1");
957         if(PS1==0)
958                 PS1 = "\\w \\$ ";
959 #endif
960 }
961
962 static inline void setup_prompt_string(int promptmode, char **prompt_str)
963 {
964         debug_printf("setup_prompt_string %d ",promptmode);
965 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
966         /* Set up the prompt */
967         if (promptmode == 1) {
968                 free(PS1);
969                 PS1=xmalloc(strlen(cwd)+4);
970                 sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ?  "$ ":"# ");
971                 *prompt_str = PS1;
972         } else {
973                 *prompt_str = PS2;
974         }
975 #else
976         *prompt_str = (promptmode==1)? PS1 : PS2;
977 #endif
978         debug_printf("result %s\n",*prompt_str);
979 }
980 #endif
981
982 static void get_user_input(struct in_str *i)
983 {
984 #ifndef __U_BOOT__
985         char *prompt_str;
986         static char the_command[BUFSIZ];
987
988         setup_prompt_string(i->promptmode, &prompt_str);
989 #ifdef CONFIG_FEATURE_COMMAND_EDITING
990         /*
991          ** enable command line editing only while a command line
992          ** is actually being read; otherwise, we'll end up bequeathing
993          ** atexit() handlers and other unwanted stuff to our
994          ** child processes (rob@sysgo.de)
995          */
996         cmdedit_read_input(prompt_str, the_command);
997 #else
998         fputs(prompt_str, stdout);
999         fflush(stdout);
1000         the_command[0]=fgetc(i->file);
1001         the_command[1]='\0';
1002 #endif
1003         fflush(stdout);
1004         i->p = the_command;
1005 #else
1006         int n;
1007         static char the_command[CONFIG_SYS_CBSIZE];
1008
1009 #ifdef CONFIG_BOOT_RETRY_TIME
1010 #  ifndef CONFIG_RESET_TO_RETRY
1011 #       error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1012 #  endif
1013         reset_cmd_timeout();
1014 #endif
1015         i->__promptme = 1;
1016         if (i->promptmode == 1) {
1017                 n = readline(CONFIG_SYS_PROMPT);
1018         } else {
1019                 n = readline(CONFIG_SYS_PROMPT_HUSH_PS2);
1020         }
1021 #ifdef CONFIG_BOOT_RETRY_TIME
1022         if (n == -2) {
1023           puts("\nTimeout waiting for command\n");
1024 #  ifdef CONFIG_RESET_TO_RETRY
1025           do_reset(NULL, 0, 0, NULL);
1026 #  else
1027 #       error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1028 #  endif
1029         }
1030 #endif
1031         if (n == -1 ) {
1032                 flag_repeat = 0;
1033                 i->__promptme = 0;
1034         }
1035         n = strlen(console_buffer);
1036         console_buffer[n] = '\n';
1037         console_buffer[n+1]= '\0';
1038         if (had_ctrlc()) flag_repeat = 0;
1039         clear_ctrlc();
1040         do_repeat = 0;
1041         if (i->promptmode == 1) {
1042                 if (console_buffer[0] == '\n'&& flag_repeat == 0) {
1043                         strcpy(the_command,console_buffer);
1044                 }
1045                 else {
1046                         if (console_buffer[0] != '\n') {
1047                                 strcpy(the_command,console_buffer);
1048                                 flag_repeat = 1;
1049                         }
1050                         else {
1051                                 do_repeat = 1;
1052                         }
1053                 }
1054                 i->p = the_command;
1055         }
1056         else {
1057                 if (console_buffer[0] != '\n') {
1058                         if (strlen(the_command) + strlen(console_buffer)
1059                             < CONFIG_SYS_CBSIZE) {
1060                                 n = strlen(the_command);
1061                                 the_command[n-1] = ' ';
1062                                 strcpy(&the_command[n],console_buffer);
1063                         }
1064                         else {
1065                                 the_command[0] = '\n';
1066                                 the_command[1] = '\0';
1067                                 flag_repeat = 0;
1068                         }
1069                 }
1070                 if (i->__promptme == 0) {
1071                         the_command[0] = '\n';
1072                         the_command[1] = '\0';
1073                 }
1074                 i->p = console_buffer;
1075         }
1076 #endif
1077 }
1078
1079 /* This is the magic location that prints prompts
1080  * and gets data back from the user */
1081 static int file_get(struct in_str *i)
1082 {
1083         int ch;
1084
1085         ch = 0;
1086         /* If there is data waiting, eat it up */
1087         if (i->p && *i->p) {
1088                 ch = *i->p++;
1089         } else {
1090                 /* need to double check i->file because we might be doing something
1091                  * more complicated by now, like sourcing or substituting. */
1092 #ifndef __U_BOOT__
1093                 if (i->__promptme && interactive && i->file == stdin) {
1094                         while(! i->p || (interactive && strlen(i->p)==0) ) {
1095 #else
1096                         while(! i->p  || strlen(i->p)==0 ) {
1097 #endif
1098                                 get_user_input(i);
1099                         }
1100                         i->promptmode=2;
1101 #ifndef __U_BOOT__
1102                         i->__promptme = 0;
1103 #endif
1104                         if (i->p && *i->p) {
1105                                 ch = *i->p++;
1106                         }
1107 #ifndef __U_BOOT__
1108                 } else {
1109                         ch = fgetc(i->file);
1110                 }
1111
1112 #endif
1113                 debug_printf("b_getch: got a %d\n", ch);
1114         }
1115 #ifndef __U_BOOT__
1116         if (ch == '\n') i->__promptme=1;
1117 #endif
1118         return ch;
1119 }
1120
1121 /* All the callers guarantee this routine will never be
1122  * used right after a newline, so prompting is not needed.
1123  */
1124 static int file_peek(struct in_str *i)
1125 {
1126 #ifndef __U_BOOT__
1127         if (i->p && *i->p) {
1128 #endif
1129                 return *i->p;
1130 #ifndef __U_BOOT__
1131         } else {
1132                 i->peek_buf[0] = fgetc(i->file);
1133                 i->peek_buf[1] = '\0';
1134                 i->p = i->peek_buf;
1135                 debug_printf("b_peek: got a %d\n", *i->p);
1136                 return *i->p;
1137         }
1138 #endif
1139 }
1140
1141 #ifndef __U_BOOT__
1142 static void setup_file_in_str(struct in_str *i, FILE *f)
1143 #else
1144 static void setup_file_in_str(struct in_str *i)
1145 #endif
1146 {
1147         i->peek = file_peek;
1148         i->get = file_get;
1149         i->__promptme=1;
1150         i->promptmode=1;
1151 #ifndef __U_BOOT__
1152         i->file = f;
1153 #endif
1154         i->p = NULL;
1155 }
1156
1157 static void setup_string_in_str(struct in_str *i, const char *s)
1158 {
1159         i->peek = static_peek;
1160         i->get = static_get;
1161         i->__promptme=1;
1162         i->promptmode=1;
1163         i->p = s;
1164 }
1165
1166 #ifndef __U_BOOT__
1167 static void mark_open(int fd)
1168 {
1169         struct close_me *new = xmalloc(sizeof(struct close_me));
1170         new->fd = fd;
1171         new->next = close_me_head;
1172         close_me_head = new;
1173 }
1174
1175 static void mark_closed(int fd)
1176 {
1177         struct close_me *tmp;
1178         if (close_me_head == NULL || close_me_head->fd != fd)
1179                 error_msg_and_die("corrupt close_me");
1180         tmp = close_me_head;
1181         close_me_head = close_me_head->next;
1182         free(tmp);
1183 }
1184
1185 static void close_all(void)
1186 {
1187         struct close_me *c;
1188         for (c=close_me_head; c; c=c->next) {
1189                 close(c->fd);
1190         }
1191         close_me_head = NULL;
1192 }
1193
1194 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1195  * and stderr if they are redirected. */
1196 static int setup_redirects(struct child_prog *prog, int squirrel[])
1197 {
1198         int openfd, mode;
1199         struct redir_struct *redir;
1200
1201         for (redir=prog->redirects; redir; redir=redir->next) {
1202                 if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1203                         /* something went wrong in the parse.  Pretend it didn't happen */
1204                         continue;
1205                 }
1206                 if (redir->dup == -1) {
1207                         mode=redir_table[redir->type].mode;
1208                         openfd = open(redir->word.gl_pathv[0], mode, 0666);
1209                         if (openfd < 0) {
1210                         /* this could get lost if stderr has been redirected, but
1211                            bash and ash both lose it as well (though zsh doesn't!) */
1212                                 perror_msg("error opening %s", redir->word.gl_pathv[0]);
1213                                 return 1;
1214                         }
1215                 } else {
1216                         openfd = redir->dup;
1217                 }
1218
1219                 if (openfd != redir->fd) {
1220                         if (squirrel && redir->fd < 3) {
1221                                 squirrel[redir->fd] = dup(redir->fd);
1222                         }
1223                         if (openfd == -3) {
1224                                 close(openfd);
1225                         } else {
1226                                 dup2(openfd, redir->fd);
1227                                 if (redir->dup == -1)
1228                                         close (openfd);
1229                         }
1230                 }
1231         }
1232         return 0;
1233 }
1234
1235 static void restore_redirects(int squirrel[])
1236 {
1237         int i, fd;
1238         for (i=0; i<3; i++) {
1239                 fd = squirrel[i];
1240                 if (fd != -1) {
1241                         /* No error checking.  I sure wouldn't know what
1242                          * to do with an error if I found one! */
1243                         dup2(fd, i);
1244                         close(fd);
1245                 }
1246         }
1247 }
1248
1249 /* never returns */
1250 /* XXX no exit() here.  If you don't exec, use _exit instead.
1251  * The at_exit handlers apparently confuse the calling process,
1252  * in particular stdin handling.  Not sure why? */
1253 static void pseudo_exec(struct child_prog *child)
1254 {
1255         int i, rcode;
1256         char *p;
1257         struct built_in_command *x;
1258         if (child->argv) {
1259                 for (i=0; is_assignment(child->argv[i]); i++) {
1260                         debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
1261                         p = insert_var_value(child->argv[i]);
1262                         putenv(strdup(p));
1263                         if (p != child->argv[i]) free(p);
1264                 }
1265                 child->argv+=i;  /* XXX this hack isn't so horrible, since we are about
1266                                         to exit, and therefore don't need to keep data
1267                                         structures consistent for free() use. */
1268                 /* If a variable is assigned in a forest, and nobody listens,
1269                  * was it ever really set?
1270                  */
1271                 if (child->argv[0] == NULL) {
1272                         _exit(EXIT_SUCCESS);
1273                 }
1274
1275                 /*
1276                  * Check if the command matches any of the builtins.
1277                  * Depending on context, this might be redundant.  But it's
1278                  * easier to waste a few CPU cycles than it is to figure out
1279                  * if this is one of those cases.
1280                  */
1281                 for (x = bltins; x->cmd; x++) {
1282                         if (strcmp(child->argv[0], x->cmd) == 0 ) {
1283                                 debug_printf("builtin exec %s\n", child->argv[0]);
1284                                 rcode = x->function(child);
1285                                 fflush(stdout);
1286                                 _exit(rcode);
1287                         }
1288                 }
1289
1290                 /* Check if the command matches any busybox internal commands
1291                  * ("applets") here.
1292                  * FIXME: This feature is not 100% safe, since
1293                  * BusyBox is not fully reentrant, so we have no guarantee the things
1294                  * from the .bss are still zeroed, or that things from .data are still
1295                  * at their defaults.  We could exec ourself from /proc/self/exe, but I
1296                  * really dislike relying on /proc for things.  We could exec ourself
1297                  * from global_argv[0], but if we are in a chroot, we may not be able
1298                  * to find ourself... */
1299 #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1300                 {
1301                         int argc_l;
1302                         char** argv_l=child->argv;
1303                         char *name = child->argv[0];
1304
1305 #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
1306                         /* Following discussions from November 2000 on the busybox mailing
1307                          * list, the default configuration, (without
1308                          * get_last_path_component()) lets the user force use of an
1309                          * external command by specifying the full (with slashes) filename.
1310                          * If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN then applets
1311                          * _aways_ override external commands, so if you want to run
1312                          * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the
1313                          * filesystem and is _not_ busybox.  Some systems may want this,
1314                          * most do not.  */
1315                         name = get_last_path_component(name);
1316 #endif
1317                         /* Count argc for use in a second... */
1318                         for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
1319                         optind = 1;
1320                         debug_printf("running applet %s\n", name);
1321                         run_applet_by_name(name, argc_l, child->argv);
1322                 }
1323 #endif
1324                 debug_printf("exec of %s\n",child->argv[0]);
1325                 execvp(child->argv[0],child->argv);
1326                 perror_msg("couldn't exec: %s",child->argv[0]);
1327                 _exit(1);
1328         } else if (child->group) {
1329                 debug_printf("runtime nesting to group\n");
1330                 interactive=0;    /* crucial!!!! */
1331                 rcode = run_list_real(child->group);
1332                 /* OK to leak memory by not calling free_pipe_list,
1333                  * since this process is about to exit */
1334                 _exit(rcode);
1335         } else {
1336                 /* Can happen.  See what bash does with ">foo" by itself. */
1337                 debug_printf("trying to pseudo_exec null command\n");
1338                 _exit(EXIT_SUCCESS);
1339         }
1340 }
1341
1342 static void insert_bg_job(struct pipe *pi)
1343 {
1344         struct pipe *thejob;
1345
1346         /* Linear search for the ID of the job to use */
1347         pi->jobid = 1;
1348         for (thejob = job_list; thejob; thejob = thejob->next)
1349                 if (thejob->jobid >= pi->jobid)
1350                         pi->jobid = thejob->jobid + 1;
1351
1352         /* add thejob to the list of running jobs */
1353         if (!job_list) {
1354                 thejob = job_list = xmalloc(sizeof(*thejob));
1355         } else {
1356                 for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
1357                 thejob->next = xmalloc(sizeof(*thejob));
1358                 thejob = thejob->next;
1359         }
1360
1361         /* physically copy the struct job */
1362         memcpy(thejob, pi, sizeof(struct pipe));
1363         thejob->next = NULL;
1364         thejob->running_progs = thejob->num_progs;
1365         thejob->stopped_progs = 0;
1366         thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1367
1368         /*if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) */
1369         {
1370                 char *bar=thejob->text;
1371                 char **foo=pi->progs[0].argv;
1372                 while(foo && *foo) {
1373                         bar += sprintf(bar, "%s ", *foo++);
1374                 }
1375         }
1376
1377         /* we don't wait for background thejobs to return -- append it
1378            to the list of backgrounded thejobs and leave it alone */
1379         printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1380         last_bg_pid = thejob->progs[0].pid;
1381         last_jobid = thejob->jobid;
1382 }
1383
1384 /* remove a backgrounded job */
1385 static void remove_bg_job(struct pipe *pi)
1386 {
1387         struct pipe *prev_pipe;
1388
1389         if (pi == job_list) {
1390                 job_list = pi->next;
1391         } else {
1392                 prev_pipe = job_list;
1393                 while (prev_pipe->next != pi)
1394                         prev_pipe = prev_pipe->next;
1395                 prev_pipe->next = pi->next;
1396         }
1397         if (job_list)
1398                 last_jobid = job_list->jobid;
1399         else
1400                 last_jobid = 0;
1401
1402         pi->stopped_progs = 0;
1403         free_pipe(pi, 0);
1404         free(pi);
1405 }
1406
1407 /* Checks to see if any processes have exited -- if they
1408    have, figure out why and see if a job has completed */
1409 static int checkjobs(struct pipe* fg_pipe)
1410 {
1411         int attributes;
1412         int status;
1413         int prognum = 0;
1414         struct pipe *pi;
1415         pid_t childpid;
1416
1417         attributes = WUNTRACED;
1418         if (fg_pipe==NULL) {
1419                 attributes |= WNOHANG;
1420         }
1421
1422         while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1423                 if (fg_pipe) {
1424                         int i, rcode = 0;
1425                         for (i=0; i < fg_pipe->num_progs; i++) {
1426                                 if (fg_pipe->progs[i].pid == childpid) {
1427                                         if (i==fg_pipe->num_progs-1)
1428                                                 rcode=WEXITSTATUS(status);
1429                                         (fg_pipe->num_progs)--;
1430                                         return(rcode);
1431                                 }
1432                         }
1433                 }
1434
1435                 for (pi = job_list; pi; pi = pi->next) {
1436                         prognum = 0;
1437                         while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1438                                 prognum++;
1439                         }
1440                         if (prognum < pi->num_progs)
1441                                 break;
1442                 }
1443
1444                 if(pi==NULL) {
1445                         debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
1446                         continue;
1447                 }
1448
1449                 if (WIFEXITED(status) || WIFSIGNALED(status)) {
1450                         /* child exited */
1451                         pi->running_progs--;
1452                         pi->progs[prognum].pid = 0;
1453
1454                         if (!pi->running_progs) {
1455                                 printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
1456                                 remove_bg_job(pi);
1457                         }
1458                 } else {
1459                         /* child stopped */
1460                         pi->stopped_progs++;
1461                         pi->progs[prognum].is_stopped = 1;
1462
1463 #if 0
1464                         /* Printing this stuff is a pain, since it tends to
1465                          * overwrite the prompt an inconveinient moments.  So
1466                          * don't do that.  */
1467                         if (pi->stopped_progs == pi->num_progs) {
1468                                 printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
1469                         }
1470 #endif
1471                 }
1472         }
1473
1474         if (childpid == -1 && errno != ECHILD)
1475                 perror_msg("waitpid");
1476
1477         /* move the shell to the foreground */
1478         /*if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) */
1479         /*      perror_msg("tcsetpgrp-2"); */
1480         return -1;
1481 }
1482
1483 /* Figure out our controlling tty, checking in order stderr,
1484  * stdin, and stdout.  If check_pgrp is set, also check that
1485  * we belong to the foreground process group associated with
1486  * that tty.  The value of shell_terminal is needed in order to call
1487  * tcsetpgrp(shell_terminal, ...); */
1488 void controlling_tty(int check_pgrp)
1489 {
1490         pid_t curpgrp;
1491
1492         if ((curpgrp = tcgetpgrp(shell_terminal = 2)) < 0
1493                         && (curpgrp = tcgetpgrp(shell_terminal = 0)) < 0
1494                         && (curpgrp = tcgetpgrp(shell_terminal = 1)) < 0)
1495                 goto shell_terminal_error;
1496
1497         if (check_pgrp && curpgrp != getpgid(0))
1498                 goto shell_terminal_error;
1499
1500         return;
1501
1502 shell_terminal_error:
1503                 shell_terminal = -1;
1504                 return;
1505 }
1506 #endif
1507
1508 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1509  * to finish.  See checkjobs().
1510  *
1511  * return code is normally -1, when the caller has to wait for children
1512  * to finish to determine the exit status of the pipe.  If the pipe
1513  * is a simple builtin command, however, the action is done by the
1514  * time run_pipe_real returns, and the exit code is provided as the
1515  * return value.
1516  *
1517  * The input of the pipe is always stdin, the output is always
1518  * stdout.  The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1519  * because it tries to avoid running the command substitution in
1520  * subshell, when that is in fact necessary.  The subshell process
1521  * now has its stdout directed to the input of the appropriate pipe,
1522  * so this routine is noticeably simpler.
1523  */
1524 static int run_pipe_real(struct pipe *pi)
1525 {
1526         int i;
1527 #ifndef __U_BOOT__
1528         int nextin, nextout;
1529         int pipefds[2];                         /* pipefds[0] is for reading */
1530         struct child_prog *child;
1531         struct built_in_command *x;
1532         char *p;
1533 # if __GNUC__
1534         /* Avoid longjmp clobbering */
1535         (void) &i;
1536         (void) &nextin;
1537         (void) &nextout;
1538         (void) &child;
1539 # endif
1540 #else
1541         int nextin;
1542         int flag = do_repeat ? CMD_FLAG_REPEAT : 0;
1543         struct child_prog *child;
1544         char *p;
1545 # if __GNUC__
1546         /* Avoid longjmp clobbering */
1547         (void) &i;
1548         (void) &nextin;
1549         (void) &child;
1550 # endif
1551 #endif  /* __U_BOOT__ */
1552
1553         nextin = 0;
1554 #ifndef __U_BOOT__
1555         pi->pgrp = -1;
1556 #endif
1557
1558         /* Check if this is a simple builtin (not part of a pipe).
1559          * Builtins within pipes have to fork anyway, and are handled in
1560          * pseudo_exec.  "echo foo | read bar" doesn't work on bash, either.
1561          */
1562         if (pi->num_progs == 1) child = & (pi->progs[0]);
1563 #ifndef __U_BOOT__
1564         if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1565                 int squirrel[] = {-1, -1, -1};
1566                 int rcode;
1567                 debug_printf("non-subshell grouping\n");
1568                 setup_redirects(child, squirrel);
1569                 /* XXX could we merge code with following builtin case,
1570                  * by creating a pseudo builtin that calls run_list_real? */
1571                 rcode = run_list_real(child->group);
1572                 restore_redirects(squirrel);
1573 #else
1574                 if (pi->num_progs == 1 && child->group) {
1575                 int rcode;
1576                 debug_printf("non-subshell grouping\n");
1577                 rcode = run_list_real(child->group);
1578 #endif
1579                 return rcode;
1580         } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1581                 for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
1582                 if (i!=0 && child->argv[i]==NULL) {
1583                         /* assignments, but no command: set the local environment */
1584                         for (i=0; child->argv[i]!=NULL; i++) {
1585
1586                                 /* Ok, this case is tricky.  We have to decide if this is a
1587                                  * local variable, or an already exported variable.  If it is
1588                                  * already exported, we have to export the new value.  If it is
1589                                  * not exported, we need only set this as a local variable.
1590                                  * This junk is all to decide whether or not to export this
1591                                  * variable. */
1592                                 int export_me=0;
1593                                 char *name, *value;
1594                                 name = xstrdup(child->argv[i]);
1595                                 debug_printf("Local environment set: %s\n", name);
1596                                 value = strchr(name, '=');
1597                                 if (value)
1598                                         *value=0;
1599 #ifndef __U_BOOT__
1600                                 if ( get_local_var(name)) {
1601                                         export_me=1;
1602                                 }
1603 #endif
1604                                 free(name);
1605                                 p = insert_var_value(child->argv[i]);
1606                                 set_local_var(p, export_me);
1607                                 if (p != child->argv[i]) free(p);
1608                         }
1609                         return EXIT_SUCCESS;   /* don't worry about errors in set_local_var() yet */
1610                 }
1611                 for (i = 0; is_assignment(child->argv[i]); i++) {
1612                         p = insert_var_value(child->argv[i]);
1613 #ifndef __U_BOOT__
1614                         putenv(strdup(p));
1615 #else
1616                         set_local_var(p, 0);
1617 #endif
1618                         if (p != child->argv[i]) {
1619                                 child->sp--;
1620                                 free(p);
1621                         }
1622                 }
1623                 if (child->sp) {
1624                         char * str = NULL;
1625
1626                         str = make_string((child->argv + i));
1627                         parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1628                         free(str);
1629                         return last_return_code;
1630                 }
1631 #ifndef __U_BOOT__
1632                 for (x = bltins; x->cmd; x++) {
1633                         if (strcmp(child->argv[i], x->cmd) == 0 ) {
1634                                 int squirrel[] = {-1, -1, -1};
1635                                 int rcode;
1636                                 if (x->function == builtin_exec && child->argv[i+1]==NULL) {
1637                                         debug_printf("magic exec\n");
1638                                         setup_redirects(child,NULL);
1639                                         return EXIT_SUCCESS;
1640                                 }
1641                                 debug_printf("builtin inline %s\n", child->argv[0]);
1642                                 /* XXX setup_redirects acts on file descriptors, not FILEs.
1643                                  * This is perfect for work that comes after exec().
1644                                  * Is it really safe for inline use?  Experimentally,
1645                                  * things seem to work with glibc. */
1646                                 setup_redirects(child, squirrel);
1647
1648                                 child->argv += i;  /* XXX horrible hack */
1649                                 rcode = x->function(child);
1650                                 /* XXX restore hack so free() can work right */
1651                                 child->argv -= i;
1652                                 restore_redirects(squirrel);
1653                         }
1654                         return rcode;
1655                 }
1656 #else
1657                 /* check ";", because ,example , argv consist from
1658                  * "help;flinfo" must not execute
1659                  */
1660                 if (strchr(child->argv[i], ';')) {
1661                         printf("Unknown command '%s' - try 'help' or use "
1662                                         "'run' command\n", child->argv[i]);
1663                         return -1;
1664                 }
1665                 /* Process the command */
1666                 return cmd_process(flag, child->argc, child->argv,
1667                                    &flag_repeat);
1668 #endif
1669         }
1670 #ifndef __U_BOOT__
1671
1672         for (i = 0; i < pi->num_progs; i++) {
1673                 child = & (pi->progs[i]);
1674
1675                 /* pipes are inserted between pairs of commands */
1676                 if ((i + 1) < pi->num_progs) {
1677                         if (pipe(pipefds)<0) perror_msg_and_die("pipe");
1678                         nextout = pipefds[1];
1679                 } else {
1680                         nextout=1;
1681                         pipefds[0] = -1;
1682                 }
1683
1684                 /* XXX test for failed fork()? */
1685                 if (!(child->pid = fork())) {
1686                         /* Set the handling for job control signals back to the default.  */
1687                         signal(SIGINT, SIG_DFL);
1688                         signal(SIGQUIT, SIG_DFL);
1689                         signal(SIGTERM, SIG_DFL);
1690                         signal(SIGTSTP, SIG_DFL);
1691                         signal(SIGTTIN, SIG_DFL);
1692                         signal(SIGTTOU, SIG_DFL);
1693                         signal(SIGCHLD, SIG_DFL);
1694
1695                         close_all();
1696
1697                         if (nextin != 0) {
1698                                 dup2(nextin, 0);
1699                                 close(nextin);
1700                         }
1701                         if (nextout != 1) {
1702                                 dup2(nextout, 1);
1703                                 close(nextout);
1704                         }
1705                         if (pipefds[0]!=-1) {
1706                                 close(pipefds[0]);  /* opposite end of our output pipe */
1707                         }
1708
1709                         /* Like bash, explicit redirects override pipes,
1710                          * and the pipe fd is available for dup'ing. */
1711                         setup_redirects(child,NULL);
1712
1713                         if (interactive && pi->followup!=PIPE_BG) {
1714                                 /* If we (the child) win the race, put ourselves in the process
1715                                  * group whose leader is the first process in this pipe. */
1716                                 if (pi->pgrp < 0) {
1717                                         pi->pgrp = getpid();
1718                                 }
1719                                 if (setpgid(0, pi->pgrp) == 0) {
1720                                         tcsetpgrp(2, pi->pgrp);
1721                                 }
1722                         }
1723
1724                         pseudo_exec(child);
1725                 }
1726
1727
1728                 /* put our child in the process group whose leader is the
1729                    first process in this pipe */
1730                 if (pi->pgrp < 0) {
1731                         pi->pgrp = child->pid;
1732                 }
1733                 /* Don't check for errors.  The child may be dead already,
1734                  * in which case setpgid returns error code EACCES. */
1735                 setpgid(child->pid, pi->pgrp);
1736
1737                 if (nextin != 0)
1738                         close(nextin);
1739                 if (nextout != 1)
1740                         close(nextout);
1741
1742                 /* If there isn't another process, nextin is garbage
1743                    but it doesn't matter */
1744                 nextin = pipefds[0];
1745         }
1746 #endif
1747         return -1;
1748 }
1749
1750 static int run_list_real(struct pipe *pi)
1751 {
1752         char *save_name = NULL;
1753         char **list = NULL;
1754         char **save_list = NULL;
1755         struct pipe *rpipe;
1756         int flag_rep = 0;
1757 #ifndef __U_BOOT__
1758         int save_num_progs;
1759 #endif
1760         int rcode=0, flag_skip=1;
1761         int flag_restore = 0;
1762         int if_code=0, next_if_code=0;  /* need double-buffer to handle elif */
1763         reserved_style rmode, skip_more_in_this_rmode=RES_XXXX;
1764         /* check syntax for "for" */
1765         for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1766                 if ((rpipe->r_mode == RES_IN ||
1767                     rpipe->r_mode == RES_FOR) &&
1768                     (rpipe->next == NULL)) {
1769                                 syntax();
1770 #ifdef __U_BOOT__
1771                                 flag_repeat = 0;
1772 #endif
1773                                 return 1;
1774                 }
1775                 if ((rpipe->r_mode == RES_IN &&
1776                         (rpipe->next->r_mode == RES_IN &&
1777                         rpipe->next->progs->argv != NULL))||
1778                         (rpipe->r_mode == RES_FOR &&
1779                         rpipe->next->r_mode != RES_IN)) {
1780                                 syntax();
1781 #ifdef __U_BOOT__
1782                                 flag_repeat = 0;
1783 #endif
1784                                 return 1;
1785                 }
1786         }
1787         for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1788                 if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
1789                         pi->r_mode == RES_FOR) {
1790 #ifdef __U_BOOT__
1791                                 /* check Ctrl-C */
1792                                 ctrlc();
1793                                 if ((had_ctrlc())) {
1794                                         return 1;
1795                                 }
1796 #endif
1797                                 flag_restore = 0;
1798                                 if (!rpipe) {
1799                                         flag_rep = 0;
1800                                         rpipe = pi;
1801                                 }
1802                 }
1803                 rmode = pi->r_mode;
1804                 debug_printf("rmode=%d  if_code=%d  next_if_code=%d skip_more=%d\n", rmode, if_code, next_if_code, skip_more_in_this_rmode);
1805                 if (rmode == skip_more_in_this_rmode && flag_skip) {
1806                         if (pi->followup == PIPE_SEQ) flag_skip=0;
1807                         continue;
1808                 }
1809                 flag_skip = 1;
1810                 skip_more_in_this_rmode = RES_XXXX;
1811                 if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
1812                 if (rmode == RES_THEN &&  if_code) continue;
1813                 if (rmode == RES_ELSE && !if_code) continue;
1814                 if (rmode == RES_ELIF && !if_code) break;
1815                 if (rmode == RES_FOR && pi->num_progs) {
1816                         if (!list) {
1817                                 /* if no variable values after "in" we skip "for" */
1818                                 if (!pi->next->progs->argv) continue;
1819                                 /* create list of variable values */
1820                                 list = make_list_in(pi->next->progs->argv,
1821                                         pi->progs->argv[0]);
1822                                 save_list = list;
1823                                 save_name = pi->progs->argv[0];
1824                                 pi->progs->argv[0] = NULL;
1825                                 flag_rep = 1;
1826                         }
1827                         if (!(*list)) {
1828                                 free(pi->progs->argv[0]);
1829                                 free(save_list);
1830                                 list = NULL;
1831                                 flag_rep = 0;
1832                                 pi->progs->argv[0] = save_name;
1833 #ifndef __U_BOOT__
1834                                 pi->progs->glob_result.gl_pathv[0] =
1835                                         pi->progs->argv[0];
1836 #endif
1837                                 continue;
1838                         } else {
1839                                 /* insert new value from list for variable */
1840                                 if (pi->progs->argv[0])
1841                                         free(pi->progs->argv[0]);
1842                                 pi->progs->argv[0] = *list++;
1843 #ifndef __U_BOOT__
1844                                 pi->progs->glob_result.gl_pathv[0] =
1845                                         pi->progs->argv[0];
1846 #endif
1847                         }
1848                 }
1849                 if (rmode == RES_IN) continue;
1850                 if (rmode == RES_DO) {
1851                         if (!flag_rep) continue;
1852                 }
1853                 if ((rmode == RES_DONE)) {
1854                         if (flag_rep) {
1855                                 flag_restore = 1;
1856                         } else {
1857                                 rpipe = NULL;
1858                         }
1859                 }
1860                 if (pi->num_progs == 0) continue;
1861 #ifndef __U_BOOT__
1862                 save_num_progs = pi->num_progs; /* save number of programs */
1863 #endif
1864                 rcode = run_pipe_real(pi);
1865                 debug_printf("run_pipe_real returned %d\n",rcode);
1866 #ifndef __U_BOOT__
1867                 if (rcode!=-1) {
1868                         /* We only ran a builtin: rcode was set by the return value
1869                          * of run_pipe_real(), and we don't need to wait for anything. */
1870                 } else if (pi->followup==PIPE_BG) {
1871                         /* XXX check bash's behavior with nontrivial pipes */
1872                         /* XXX compute jobid */
1873                         /* XXX what does bash do with attempts to background builtins? */
1874                         insert_bg_job(pi);
1875                         rcode = EXIT_SUCCESS;
1876                 } else {
1877                         if (interactive) {
1878                                 /* move the new process group into the foreground */
1879                                 if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1880                                         perror_msg("tcsetpgrp-3");
1881                                 rcode = checkjobs(pi);
1882                                 /* move the shell to the foreground */
1883                                 if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1884                                         perror_msg("tcsetpgrp-4");
1885                         } else {
1886                                 rcode = checkjobs(pi);
1887                         }
1888                         debug_printf("checkjobs returned %d\n",rcode);
1889                 }
1890                 last_return_code=rcode;
1891 #else
1892                 if (rcode < -1) {
1893                         last_return_code = -rcode - 2;
1894                         return -2;      /* exit */
1895                 }
1896                 last_return_code=(rcode == 0) ? 0 : 1;
1897 #endif
1898 #ifndef __U_BOOT__
1899                 pi->num_progs = save_num_progs; /* restore number of programs */
1900 #endif
1901                 if ( rmode == RES_IF || rmode == RES_ELIF )
1902                         next_if_code=rcode;  /* can be overwritten a number of times */
1903                 if (rmode == RES_WHILE)
1904                         flag_rep = !last_return_code;
1905                 if (rmode == RES_UNTIL)
1906                         flag_rep = last_return_code;
1907                 if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
1908                      (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
1909                         skip_more_in_this_rmode=rmode;
1910 #ifndef __U_BOOT__
1911                 checkjobs(NULL);
1912 #endif
1913         }
1914         return rcode;
1915 }
1916
1917 /* broken, of course, but OK for testing */
1918 static char *indenter(int i)
1919 {
1920         static char blanks[]="                                    ";
1921         return &blanks[sizeof(blanks)-i-1];
1922 }
1923
1924 /* return code is the exit status of the pipe */
1925 static int free_pipe(struct pipe *pi, int indent)
1926 {
1927         char **p;
1928         struct child_prog *child;
1929 #ifndef __U_BOOT__
1930         struct redir_struct *r, *rnext;
1931 #endif
1932         int a, i, ret_code=0;
1933         char *ind = indenter(indent);
1934
1935 #ifndef __U_BOOT__
1936         if (pi->stopped_progs > 0)
1937                 return ret_code;
1938         final_printf("%s run pipe: (pid %d)\n",ind,getpid());
1939 #endif
1940         for (i=0; i<pi->num_progs; i++) {
1941                 child = &pi->progs[i];
1942                 final_printf("%s  command %d:\n",ind,i);
1943                 if (child->argv) {
1944                         for (a=0,p=child->argv; *p; a++,p++) {
1945                                 final_printf("%s   argv[%d] = %s\n",ind,a,*p);
1946                         }
1947 #ifndef __U_BOOT__
1948                         globfree(&child->glob_result);
1949 #else
1950                         for (a = 0; a < child->argc; a++) {
1951                                 free(child->argv[a]);
1952                         }
1953                                         free(child->argv);
1954                         child->argc = 0;
1955 #endif
1956                         child->argv=NULL;
1957                 } else if (child->group) {
1958 #ifndef __U_BOOT__
1959                         final_printf("%s   begin group (subshell:%d)\n",ind, child->subshell);
1960 #endif
1961                         ret_code = free_pipe_list(child->group,indent+3);
1962                         final_printf("%s   end group\n",ind);
1963                 } else {
1964                         final_printf("%s   (nil)\n",ind);
1965                 }
1966 #ifndef __U_BOOT__
1967                 for (r=child->redirects; r; r=rnext) {
1968                         final_printf("%s   redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
1969                         if (r->dup == -1) {
1970                                 /* guard against the case >$FOO, where foo is unset or blank */
1971                                 if (r->word.gl_pathv) {
1972                                         final_printf(" %s\n", *r->word.gl_pathv);
1973                                         globfree(&r->word);
1974                                 }
1975                         } else {
1976                                 final_printf("&%d\n", r->dup);
1977                         }
1978                         rnext=r->next;
1979                         free(r);
1980                 }
1981                 child->redirects=NULL;
1982 #endif
1983         }
1984         free(pi->progs);   /* children are an array, they get freed all at once */
1985         pi->progs=NULL;
1986         return ret_code;
1987 }
1988
1989 static int free_pipe_list(struct pipe *head, int indent)
1990 {
1991         int rcode=0;   /* if list has no members */
1992         struct pipe *pi, *next;
1993         char *ind = indenter(indent);
1994         for (pi=head; pi; pi=next) {
1995                 final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
1996                 rcode = free_pipe(pi, indent);
1997                 final_printf("%s pipe followup code %d\n", ind, pi->followup);
1998                 next=pi->next;
1999                 pi->next=NULL;
2000                 free(pi);
2001         }
2002         return rcode;
2003 }
2004
2005 /* Select which version we will use */
2006 static int run_list(struct pipe *pi)
2007 {
2008         int rcode=0;
2009 #ifndef __U_BOOT__
2010         if (fake_mode==0) {
2011 #endif
2012                 rcode = run_list_real(pi);
2013 #ifndef __U_BOOT__
2014         }
2015 #endif
2016         /* free_pipe_list has the side effect of clearing memory
2017          * In the long run that function can be merged with run_list_real,
2018          * but doing that now would hobble the debugging effort. */
2019         free_pipe_list(pi,0);
2020         return rcode;
2021 }
2022
2023 /* The API for glob is arguably broken.  This routine pushes a non-matching
2024  * string into the output structure, removing non-backslashed backslashes.
2025  * If someone can prove me wrong, by performing this function within the
2026  * original glob(3) api, feel free to rewrite this routine into oblivion.
2027  * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
2028  * XXX broken if the last character is '\\', check that before calling.
2029  */
2030 #ifndef __U_BOOT__
2031 static int globhack(const char *src, int flags, glob_t *pglob)
2032 {
2033         int cnt=0, pathc;
2034         const char *s;
2035         char *dest;
2036         for (cnt=1, s=src; s && *s; s++) {
2037                 if (*s == '\\') s++;
2038                 cnt++;
2039         }
2040         dest = malloc(cnt);
2041         if (!dest) return GLOB_NOSPACE;
2042         if (!(flags & GLOB_APPEND)) {
2043                 pglob->gl_pathv=NULL;
2044                 pglob->gl_pathc=0;
2045                 pglob->gl_offs=0;
2046                 pglob->gl_offs=0;
2047         }
2048         pathc = ++pglob->gl_pathc;
2049         pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
2050         if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
2051         pglob->gl_pathv[pathc-1]=dest;
2052         pglob->gl_pathv[pathc]=NULL;
2053         for (s=src; s && *s; s++, dest++) {
2054                 if (*s == '\\') s++;
2055                 *dest = *s;
2056         }
2057         *dest='\0';
2058         return 0;
2059 }
2060
2061 /* XXX broken if the last character is '\\', check that before calling */
2062 static int glob_needed(const char *s)
2063 {
2064         for (; *s; s++) {
2065                 if (*s == '\\') s++;
2066                 if (strchr("*[?",*s)) return 1;
2067         }
2068         return 0;
2069 }
2070
2071 #if 0
2072 static void globprint(glob_t *pglob)
2073 {
2074         int i;
2075         debug_printf("glob_t at %p:\n", pglob);
2076         debug_printf("  gl_pathc=%d  gl_pathv=%p  gl_offs=%d  gl_flags=%d\n",
2077                 pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
2078         for (i=0; i<pglob->gl_pathc; i++)
2079                 debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
2080                         pglob->gl_pathv[i], pglob->gl_pathv[i]);
2081 }
2082 #endif
2083
2084 static int xglob(o_string *dest, int flags, glob_t *pglob)
2085 {
2086         int gr;
2087
2088         /* short-circuit for null word */
2089         /* we can code this better when the debug_printf's are gone */
2090         if (dest->length == 0) {
2091                 if (dest->nonnull) {
2092                         /* bash man page calls this an "explicit" null */
2093                         gr = globhack(dest->data, flags, pglob);
2094                         debug_printf("globhack returned %d\n",gr);
2095                 } else {
2096                         return 0;
2097                 }
2098         } else if (glob_needed(dest->data)) {
2099                 gr = glob(dest->data, flags, NULL, pglob);
2100                 debug_printf("glob returned %d\n",gr);
2101                 if (gr == GLOB_NOMATCH) {
2102                         /* quote removal, or more accurately, backslash removal */
2103                         gr = globhack(dest->data, flags, pglob);
2104                         debug_printf("globhack returned %d\n",gr);
2105                 }
2106         } else {
2107                 gr = globhack(dest->data, flags, pglob);
2108                 debug_printf("globhack returned %d\n",gr);
2109         }
2110         if (gr == GLOB_NOSPACE)
2111                 error_msg_and_die("out of memory during glob");
2112         if (gr != 0) { /* GLOB_ABORTED ? */
2113                 error_msg("glob(3) error %d",gr);
2114         }
2115         /* globprint(glob_target); */
2116         return gr;
2117 }
2118 #endif
2119
2120 #ifdef __U_BOOT__
2121 static char *get_dollar_var(char ch);
2122 #endif
2123
2124 /* This is used to get/check local shell variables */
2125 char *get_local_var(const char *s)
2126 {
2127         struct variables *cur;
2128
2129         if (!s)
2130                 return NULL;
2131
2132 #ifdef __U_BOOT__
2133         if (*s == '$')
2134                 return get_dollar_var(s[1]);
2135 #endif
2136
2137         for (cur = top_vars; cur; cur=cur->next)
2138                 if(strcmp(cur->name, s)==0)
2139                         return cur->value;
2140         return NULL;
2141 }
2142
2143 /* This is used to set local shell variables
2144    flg_export==0 if only local (not exporting) variable
2145    flg_export==1 if "new" exporting environ
2146    flg_export>1  if current startup environ (not call putenv()) */
2147 int set_local_var(const char *s, int flg_export)
2148 {
2149         char *name, *value;
2150         int result=0;
2151         struct variables *cur;
2152
2153 #ifdef __U_BOOT__
2154         /* might be possible! */
2155         if (!isalpha(*s))
2156                 return -1;
2157 #endif
2158
2159         name=strdup(s);
2160
2161 #ifdef __U_BOOT__
2162         if (getenv(name) != NULL) {
2163                 printf ("ERROR: "
2164                                 "There is a global environment variable with the same name.\n");
2165                 free(name);
2166                 return -1;
2167         }
2168 #endif
2169         /* Assume when we enter this function that we are already in
2170          * NAME=VALUE format.  So the first order of business is to
2171          * split 's' on the '=' into 'name' and 'value' */
2172         value = strchr(name, '=');
2173         if (value==0 && ++value==0) {
2174                 free(name);
2175                 return -1;
2176         }
2177         *value++ = 0;
2178
2179         for(cur = top_vars; cur; cur = cur->next) {
2180                 if(strcmp(cur->name, name)==0)
2181                         break;
2182         }
2183
2184         if(cur) {
2185                 if(strcmp(cur->value, value)==0) {
2186                         if(flg_export>0 && cur->flg_export==0)
2187                                 cur->flg_export=flg_export;
2188                         else
2189                                 result++;
2190                 } else {
2191                         if(cur->flg_read_only) {
2192                                 error_msg("%s: readonly variable", name);
2193                                 result = -1;
2194                         } else {
2195                                 if(flg_export>0 || cur->flg_export>1)
2196                                         cur->flg_export=1;
2197                                 free(cur->value);
2198
2199                                 cur->value = strdup(value);
2200                         }
2201                 }
2202         } else {
2203                 cur = malloc(sizeof(struct variables));
2204                 if(!cur) {
2205                         result = -1;
2206                 } else {
2207                         cur->name = strdup(name);
2208                         if(cur->name == 0) {
2209                                 free(cur);
2210                                 result = -1;
2211                         } else {
2212                                 struct variables *bottom = top_vars;
2213                                 cur->value = strdup(value);
2214                                 cur->next = 0;
2215                                 cur->flg_export = flg_export;
2216                                 cur->flg_read_only = 0;
2217                                 while(bottom->next) bottom=bottom->next;
2218                                 bottom->next = cur;
2219                         }
2220                 }
2221         }
2222
2223 #ifndef __U_BOOT__
2224         if(result==0 && cur->flg_export==1) {
2225                 *(value-1) = '=';
2226                 result = putenv(name);
2227         } else {
2228 #endif
2229                 free(name);
2230 #ifndef __U_BOOT__
2231                 if(result>0)            /* equivalent to previous set */
2232                         result = 0;
2233         }
2234 #endif
2235         return result;
2236 }
2237
2238 void unset_local_var(const char *name)
2239 {
2240         struct variables *cur;
2241
2242         if (name) {
2243                 for (cur = top_vars; cur; cur=cur->next) {
2244                         if(strcmp(cur->name, name)==0)
2245                                 break;
2246                 }
2247                 if(cur!=0) {
2248                         struct variables *next = top_vars;
2249                         if(cur->flg_read_only) {
2250                                 error_msg("%s: readonly variable", name);
2251                                 return;
2252                         } else {
2253 #ifndef __U_BOOT__
2254                                 if(cur->flg_export)
2255                                         unsetenv(cur->name);
2256 #endif
2257                                 free(cur->name);
2258                                 free(cur->value);
2259                                 while (next->next != cur)
2260                                         next = next->next;
2261                                 next->next = cur->next;
2262                         }
2263                         free(cur);
2264                 }
2265         }
2266 }
2267
2268 static int is_assignment(const char *s)
2269 {
2270         if (s == NULL)
2271                 return 0;
2272
2273         if (!isalpha(*s)) return 0;
2274         ++s;
2275         while(isalnum(*s) || *s=='_') ++s;
2276         return *s=='=';
2277 }
2278
2279 #ifndef __U_BOOT__
2280 /* the src parameter allows us to peek forward to a possible &n syntax
2281  * for file descriptor duplication, e.g., "2>&1".
2282  * Return code is 0 normally, 1 if a syntax error is detected in src.
2283  * Resource errors (in xmalloc) cause the process to exit */
2284 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
2285         struct in_str *input)
2286 {
2287         struct child_prog *child=ctx->child;
2288         struct redir_struct *redir = child->redirects;
2289         struct redir_struct *last_redir=NULL;
2290
2291         /* Create a new redir_struct and drop it onto the end of the linked list */
2292         while(redir) {
2293                 last_redir=redir;
2294                 redir=redir->next;
2295         }
2296         redir = xmalloc(sizeof(struct redir_struct));
2297         redir->next=NULL;
2298         redir->word.gl_pathv=NULL;
2299         if (last_redir) {
2300                 last_redir->next=redir;
2301         } else {
2302                 child->redirects=redir;
2303         }
2304
2305         redir->type=style;
2306         redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
2307
2308         debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
2309
2310         /* Check for a '2>&1' type redirect */
2311         redir->dup = redirect_dup_num(input);
2312         if (redir->dup == -2) return 1;  /* syntax error */
2313         if (redir->dup != -1) {
2314                 /* Erik had a check here that the file descriptor in question
2315                  * is legit; I postpone that to "run time"
2316                  * A "-" representation of "close me" shows up as a -3 here */
2317                 debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
2318         } else {
2319                 /* We do _not_ try to open the file that src points to,
2320                  * since we need to return and let src be expanded first.
2321                  * Set ctx->pending_redirect, so we know what to do at the
2322                  * end of the next parsed word.
2323                  */
2324                 ctx->pending_redirect = redir;
2325         }
2326         return 0;
2327 }
2328 #endif
2329
2330 struct pipe *new_pipe(void) {
2331         struct pipe *pi;
2332         pi = xmalloc(sizeof(struct pipe));
2333         pi->num_progs = 0;
2334         pi->progs = NULL;
2335         pi->next = NULL;
2336         pi->followup = 0;  /* invalid */
2337         pi->r_mode = RES_NONE;
2338         return pi;
2339 }
2340
2341 static void initialize_context(struct p_context *ctx)
2342 {
2343         ctx->pipe=NULL;
2344 #ifndef __U_BOOT__
2345         ctx->pending_redirect=NULL;
2346 #endif
2347         ctx->child=NULL;
2348         ctx->list_head=new_pipe();
2349         ctx->pipe=ctx->list_head;
2350         ctx->w=RES_NONE;
2351         ctx->stack=NULL;
2352 #ifdef __U_BOOT__
2353         ctx->old_flag=0;
2354 #endif
2355         done_command(ctx);   /* creates the memory for working child */
2356 }
2357
2358 /* normal return is 0
2359  * if a reserved word is found, and processed, return 1
2360  * should handle if, then, elif, else, fi, for, while, until, do, done.
2361  * case, function, and select are obnoxious, save those for later.
2362  */
2363 struct reserved_combo {
2364         char *literal;
2365         int code;
2366         long flag;
2367 };
2368 /* Mostly a list of accepted follow-up reserved words.
2369  * FLAG_END means we are done with the sequence, and are ready
2370  * to turn the compound list into a command.
2371  * FLAG_START means the word must start a new compound list.
2372  */
2373 static struct reserved_combo reserved_list[] = {
2374         { "if",    RES_IF,    FLAG_THEN | FLAG_START },
2375         { "then",  RES_THEN,  FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2376         { "elif",  RES_ELIF,  FLAG_THEN },
2377         { "else",  RES_ELSE,  FLAG_FI   },
2378         { "fi",    RES_FI,    FLAG_END  },
2379         { "for",   RES_FOR,   FLAG_IN   | FLAG_START },
2380         { "while", RES_WHILE, FLAG_DO   | FLAG_START },
2381         { "until", RES_UNTIL, FLAG_DO   | FLAG_START },
2382         { "in",    RES_IN,    FLAG_DO   },
2383         { "do",    RES_DO,    FLAG_DONE },
2384         { "done",  RES_DONE,  FLAG_END  }
2385 };
2386 #define NRES (sizeof(reserved_list)/sizeof(struct reserved_combo))
2387
2388 int reserved_word(o_string *dest, struct p_context *ctx)
2389 {
2390         struct reserved_combo *r;
2391         for (r=reserved_list;
2392                 r<reserved_list+NRES; r++) {
2393                 if (strcmp(dest->data, r->literal) == 0) {
2394                         debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2395                         if (r->flag & FLAG_START) {
2396                                 struct p_context *new = xmalloc(sizeof(struct p_context));
2397                                 debug_printf("push stack\n");
2398                                 if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2399                                         syntax();
2400                                         free(new);
2401                                         ctx->w = RES_SNTX;
2402                                         b_reset(dest);
2403                                         return 1;
2404                                 }
2405                                 *new = *ctx;   /* physical copy */
2406                                 initialize_context(ctx);
2407                                 ctx->stack=new;
2408                         } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2409                                 syntax();
2410                                 ctx->w = RES_SNTX;
2411                                 b_reset(dest);
2412                                 return 1;
2413                         }
2414                         ctx->w=r->code;
2415                         ctx->old_flag = r->flag;
2416                         if (ctx->old_flag & FLAG_END) {
2417                                 struct p_context *old;
2418                                 debug_printf("pop stack\n");
2419                                 done_pipe(ctx,PIPE_SEQ);
2420                                 old = ctx->stack;
2421                                 old->child->group = ctx->list_head;
2422 #ifndef __U_BOOT__
2423                                 old->child->subshell = 0;
2424 #endif
2425                                 *ctx = *old;   /* physical copy */
2426                                 free(old);
2427                         }
2428                         b_reset (dest);
2429                         return 1;
2430                 }
2431         }
2432         return 0;
2433 }
2434
2435 /* normal return is 0.
2436  * Syntax or xglob errors return 1. */
2437 static int done_word(o_string *dest, struct p_context *ctx)
2438 {
2439         struct child_prog *child=ctx->child;
2440 #ifndef __U_BOOT__
2441         glob_t *glob_target;
2442         int gr, flags = 0;
2443 #else
2444         char *str, *s;
2445         int argc, cnt;
2446 #endif
2447
2448         debug_printf("done_word: %s %p\n", dest->data, child);
2449         if (dest->length == 0 && !dest->nonnull) {
2450                 debug_printf("  true null, ignored\n");
2451                 return 0;
2452         }
2453 #ifndef __U_BOOT__
2454         if (ctx->pending_redirect) {
2455                 glob_target = &ctx->pending_redirect->word;
2456         } else {
2457 #endif
2458                 if (child->group) {
2459                         syntax();
2460                         return 1;  /* syntax error, groups and arglists don't mix */
2461                 }
2462                 if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2463                         debug_printf("checking %s for reserved-ness\n",dest->data);
2464                         if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2465                 }
2466 #ifndef __U_BOOT__
2467                 glob_target = &child->glob_result;
2468                 if (child->argv) flags |= GLOB_APPEND;
2469 #else
2470                 for (cnt = 1, s = dest->data; s && *s; s++) {
2471                         if (*s == '\\') s++;
2472                         cnt++;
2473                 }
2474                 str = malloc(cnt);
2475                 if (!str) return 1;
2476                 if ( child->argv == NULL) {
2477                         child->argc=0;
2478                 }
2479                 argc = ++child->argc;
2480                 child->argv = realloc(child->argv, (argc+1)*sizeof(*child->argv));
2481                 if (child->argv == NULL) return 1;
2482                 child->argv[argc-1]=str;
2483                 child->argv[argc]=NULL;
2484                 for (s = dest->data; s && *s; s++,str++) {
2485                         if (*s == '\\') s++;
2486                         *str = *s;
2487                 }
2488                 *str = '\0';
2489 #endif
2490 #ifndef __U_BOOT__
2491         }
2492         gr = xglob(dest, flags, glob_target);
2493         if (gr != 0) return 1;
2494 #endif
2495
2496         b_reset(dest);
2497 #ifndef __U_BOOT__
2498         if (ctx->pending_redirect) {
2499                 ctx->pending_redirect=NULL;
2500                 if (glob_target->gl_pathc != 1) {
2501                         error_msg("ambiguous redirect");
2502                         return 1;
2503                 }
2504         } else {
2505                 child->argv = glob_target->gl_pathv;
2506         }
2507 #endif
2508         if (ctx->w == RES_FOR) {
2509                 done_word(dest,ctx);
2510                 done_pipe(ctx,PIPE_SEQ);
2511         }
2512         return 0;
2513 }
2514
2515 /* The only possible error here is out of memory, in which case
2516  * xmalloc exits. */
2517 static int done_command(struct p_context *ctx)
2518 {
2519         /* The child is really already in the pipe structure, so
2520          * advance the pipe counter and make a new, null child.
2521          * Only real trickiness here is that the uncommitted
2522          * child structure, to which ctx->child points, is not
2523          * counted in pi->num_progs. */
2524         struct pipe *pi=ctx->pipe;
2525         struct child_prog *prog=ctx->child;
2526
2527         if (prog && prog->group == NULL
2528                  && prog->argv == NULL
2529 #ifndef __U_BOOT__
2530                  && prog->redirects == NULL) {
2531 #else
2532                                                                                 ) {
2533 #endif
2534                 debug_printf("done_command: skipping null command\n");
2535                 return 0;
2536         } else if (prog) {
2537                 pi->num_progs++;
2538                 debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2539         } else {
2540                 debug_printf("done_command: initializing\n");
2541         }
2542         pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2543
2544         prog = pi->progs + pi->num_progs;
2545 #ifndef __U_BOOT__
2546         prog->redirects = NULL;
2547 #endif
2548         prog->argv = NULL;
2549 #ifndef __U_BOOT__
2550         prog->is_stopped = 0;
2551 #endif
2552         prog->group = NULL;
2553 #ifndef __U_BOOT__
2554         prog->glob_result.gl_pathv = NULL;
2555         prog->family = pi;
2556 #endif
2557         prog->sp = 0;
2558         ctx->child = prog;
2559         prog->type = ctx->type;
2560
2561         /* but ctx->pipe and ctx->list_head remain unchanged */
2562         return 0;
2563 }
2564
2565 static int done_pipe(struct p_context *ctx, pipe_style type)
2566 {
2567         struct pipe *new_p;
2568         done_command(ctx);  /* implicit closure of previous command */
2569         debug_printf("done_pipe, type %d\n", type);
2570         ctx->pipe->followup = type;
2571         ctx->pipe->r_mode = ctx->w;
2572         new_p=new_pipe();
2573         ctx->pipe->next = new_p;
2574         ctx->pipe = new_p;
2575         ctx->child = NULL;
2576         done_command(ctx);  /* set up new pipe to accept commands */
2577         return 0;
2578 }
2579
2580 #ifndef __U_BOOT__
2581 /* peek ahead in the in_str to find out if we have a "&n" construct,
2582  * as in "2>&1", that represents duplicating a file descriptor.
2583  * returns either -2 (syntax error), -1 (no &), or the number found.
2584  */
2585 static int redirect_dup_num(struct in_str *input)
2586 {
2587         int ch, d=0, ok=0;
2588         ch = b_peek(input);
2589         if (ch != '&') return -1;
2590
2591         b_getch(input);  /* get the & */
2592         ch=b_peek(input);
2593         if (ch == '-') {
2594                 b_getch(input);
2595                 return -3;  /* "-" represents "close me" */
2596         }
2597         while (isdigit(ch)) {
2598                 d = d*10+(ch-'0');
2599                 ok=1;
2600                 b_getch(input);
2601                 ch = b_peek(input);
2602         }
2603         if (ok) return d;
2604
2605         error_msg("ambiguous redirect");
2606         return -2;
2607 }
2608
2609 /* If a redirect is immediately preceded by a number, that number is
2610  * supposed to tell which file descriptor to redirect.  This routine
2611  * looks for such preceding numbers.  In an ideal world this routine
2612  * needs to handle all the following classes of redirects...
2613  *     echo 2>foo     # redirects fd  2 to file "foo", nothing passed to echo
2614  *     echo 49>foo    # redirects fd 49 to file "foo", nothing passed to echo
2615  *     echo -2>foo    # redirects fd  1 to file "foo",    "-2" passed to echo
2616  *     echo 49x>foo   # redirects fd  1 to file "foo",   "49x" passed to echo
2617  * A -1 output from this program means no valid number was found, so the
2618  * caller should use the appropriate default for this redirection.
2619  */
2620 static int redirect_opt_num(o_string *o)
2621 {
2622         int num;
2623
2624         if (o->length==0) return -1;
2625         for(num=0; num<o->length; num++) {
2626                 if (!isdigit(*(o->data+num))) {
2627                         return -1;
2628                 }
2629         }
2630         /* reuse num (and save an int) */
2631         num=atoi(o->data);
2632         b_reset(o);
2633         return num;
2634 }
2635
2636 FILE *generate_stream_from_list(struct pipe *head)
2637 {
2638         FILE *pf;
2639 #if 1
2640         int pid, channel[2];
2641         if (pipe(channel)<0) perror_msg_and_die("pipe");
2642         pid=fork();
2643         if (pid<0) {
2644                 perror_msg_and_die("fork");
2645         } else if (pid==0) {
2646                 close(channel[0]);
2647                 if (channel[1] != 1) {
2648                         dup2(channel[1],1);
2649                         close(channel[1]);
2650                 }
2651 #if 0
2652 #define SURROGATE "surrogate response"
2653                 write(1,SURROGATE,sizeof(SURROGATE));
2654                 _exit(run_list(head));
2655 #else
2656                 _exit(run_list_real(head));   /* leaks memory */
2657 #endif
2658         }
2659         debug_printf("forked child %d\n",pid);
2660         close(channel[1]);
2661         pf = fdopen(channel[0],"r");
2662         debug_printf("pipe on FILE *%p\n",pf);
2663 #else
2664         free_pipe_list(head,0);
2665         pf=popen("echo surrogate response","r");
2666         debug_printf("started fake pipe on FILE *%p\n",pf);
2667 #endif
2668         return pf;
2669 }
2670
2671 /* this version hacked for testing purposes */
2672 /* return code is exit status of the process that is run. */
2673 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2674 {
2675         int retcode;
2676         o_string result=NULL_O_STRING;
2677         struct p_context inner;
2678         FILE *p;
2679         struct in_str pipe_str;
2680         initialize_context(&inner);
2681
2682         /* recursion to generate command */
2683         retcode = parse_stream(&result, &inner, input, subst_end);
2684         if (retcode != 0) return retcode;  /* syntax error or EOF */
2685         done_word(&result, &inner);
2686         done_pipe(&inner, PIPE_SEQ);
2687         b_free(&result);
2688
2689         p=generate_stream_from_list(inner.list_head);
2690         if (p==NULL) return 1;
2691         mark_open(fileno(p));
2692         setup_file_in_str(&pipe_str, p);
2693
2694         /* now send results of command back into original context */
2695         retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2696         /* XXX In case of a syntax error, should we try to kill the child?
2697          * That would be tough to do right, so just read until EOF. */
2698         if (retcode == 1) {
2699                 while (b_getch(&pipe_str)!=EOF) { /* discard */ };
2700         }
2701
2702         debug_printf("done reading from pipe, pclose()ing\n");
2703         /* This is the step that wait()s for the child.  Should be pretty
2704          * safe, since we just read an EOF from its stdout.  We could try
2705          * to better, by using wait(), and keeping track of background jobs
2706          * at the same time.  That would be a lot of work, and contrary
2707          * to the KISS philosophy of this program. */
2708         mark_closed(fileno(p));
2709         retcode=pclose(p);
2710         free_pipe_list(inner.list_head,0);
2711         debug_printf("pclosed, retcode=%d\n",retcode);
2712         /* XXX this process fails to trim a single trailing newline */
2713         return retcode;
2714 }
2715
2716 static int parse_group(o_string *dest, struct p_context *ctx,
2717         struct in_str *input, int ch)
2718 {
2719         int rcode, endch=0;
2720         struct p_context sub;
2721         struct child_prog *child = ctx->child;
2722         if (child->argv) {
2723                 syntax();
2724                 return 1;  /* syntax error, groups and arglists don't mix */
2725         }
2726         initialize_context(&sub);
2727         switch(ch) {
2728                 case '(': endch=')'; child->subshell=1; break;
2729                 case '{': endch='}'; break;
2730                 default: syntax();   /* really logic error */
2731         }
2732         rcode=parse_stream(dest,&sub,input,endch);
2733         done_word(dest,&sub); /* finish off the final word in the subcontext */
2734         done_pipe(&sub, PIPE_SEQ);  /* and the final command there, too */
2735         child->group = sub.list_head;
2736         return rcode;
2737         /* child remains "open", available for possible redirects */
2738 }
2739 #endif
2740
2741 /* basically useful version until someone wants to get fancier,
2742  * see the bash man page under "Parameter Expansion" */
2743 static char *lookup_param(char *src)
2744 {
2745         char *p;
2746
2747         if (!src)
2748                 return NULL;
2749
2750                 p = getenv(src);
2751                 if (!p)
2752                         p = get_local_var(src);
2753
2754         return p;
2755 }
2756
2757 #ifdef __U_BOOT__
2758 static char *get_dollar_var(char ch)
2759 {
2760         static char buf[40];
2761
2762         buf[0] = '\0';
2763         switch (ch) {
2764                 case '?':
2765                         sprintf(buf, "%u", (unsigned int)last_return_code);
2766                         break;
2767                 default:
2768                         return NULL;
2769         }
2770         return buf;
2771 }
2772 #endif
2773
2774 /* return code: 0 for OK, 1 for syntax error */
2775 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2776 {
2777 #ifndef __U_BOOT__
2778         int i, advance=0;
2779 #else
2780         int advance=0;
2781 #endif
2782 #ifndef __U_BOOT__
2783         char sep[]=" ";
2784 #endif
2785         int ch = input->peek(input);  /* first character after the $ */
2786         debug_printf("handle_dollar: ch=%c\n",ch);
2787         if (isalpha(ch)) {
2788                 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2789                 ctx->child->sp++;
2790                 while(ch=b_peek(input),isalnum(ch) || ch=='_') {
2791                         b_getch(input);
2792                         b_addchr(dest,ch);
2793                 }
2794                 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2795 #ifndef __U_BOOT__
2796         } else if (isdigit(ch)) {
2797                 i = ch-'0';  /* XXX is $0 special? */
2798                 if (i<global_argc) {
2799                         parse_string(dest, ctx, global_argv[i]); /* recursion */
2800                 }
2801                 advance = 1;
2802 #endif
2803         } else switch (ch) {
2804 #ifndef __U_BOOT__
2805                 case '$':
2806                         b_adduint(dest,getpid());
2807                         advance = 1;
2808                         break;
2809                 case '!':
2810                         if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2811                         advance = 1;
2812                         break;
2813 #endif
2814                 case '?':
2815 #ifndef __U_BOOT__
2816                         b_adduint(dest,last_return_code);
2817 #else
2818                         ctx->child->sp++;
2819                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2820                         b_addchr(dest, '$');
2821                         b_addchr(dest, '?');
2822                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2823 #endif
2824                         advance = 1;
2825                         break;
2826 #ifndef __U_BOOT__
2827                 case '#':
2828                         b_adduint(dest,global_argc ? global_argc-1 : 0);
2829                         advance = 1;
2830                         break;
2831 #endif
2832                 case '{':
2833                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2834                         ctx->child->sp++;
2835                         b_getch(input);
2836                         /* XXX maybe someone will try to escape the '}' */
2837                         while(ch=b_getch(input),ch!=EOF && ch!='}') {
2838                                 b_addchr(dest,ch);
2839                         }
2840                         if (ch != '}') {
2841                                 syntax();
2842                                 return 1;
2843                         }
2844                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2845                         break;
2846 #ifndef __U_BOOT__
2847                 case '(':
2848                         b_getch(input);
2849                         process_command_subs(dest, ctx, input, ')');
2850                         break;
2851                 case '*':
2852                         sep[0]=ifs[0];
2853                         for (i=1; i<global_argc; i++) {
2854                                 parse_string(dest, ctx, global_argv[i]);
2855                                 if (i+1 < global_argc) parse_string(dest, ctx, sep);
2856                         }
2857                         break;
2858                 case '@':
2859                 case '-':
2860                 case '_':
2861                         /* still unhandled, but should be eventually */
2862                         error_msg("unhandled syntax: $%c",ch);
2863                         return 1;
2864                         break;
2865 #endif
2866                 default:
2867                         b_addqchr(dest,'$',dest->quote);
2868         }
2869         /* Eat the character if the flag was set.  If the compiler
2870          * is smart enough, we could substitute "b_getch(input);"
2871          * for all the "advance = 1;" above, and also end up with
2872          * a nice size-optimized program.  Hah!  That'll be the day.
2873          */
2874         if (advance) b_getch(input);
2875         return 0;
2876 }
2877
2878 #ifndef __U_BOOT__
2879 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2880 {
2881         struct in_str foo;
2882         setup_string_in_str(&foo, src);
2883         return parse_stream(dest, ctx, &foo, '\0');
2884 }
2885 #endif
2886
2887 /* return code is 0 for normal exit, 1 for syntax error */
2888 int parse_stream(o_string *dest, struct p_context *ctx,
2889         struct in_str *input, int end_trigger)
2890 {
2891         unsigned int ch, m;
2892 #ifndef __U_BOOT__
2893         int redir_fd;
2894         redir_type redir_style;
2895 #endif
2896         int next;
2897
2898         /* Only double-quote state is handled in the state variable dest->quote.
2899          * A single-quote triggers a bypass of the main loop until its mate is
2900          * found.  When recursing, quote state is passed in via dest->quote. */
2901
2902         debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2903         while ((ch=b_getch(input))!=EOF) {
2904                 m = map[ch];
2905 #ifdef __U_BOOT__
2906                 if (input->__promptme == 0) return 1;
2907 #endif
2908                 next = (ch == '\n') ? 0 : b_peek(input);
2909
2910                 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d - %c\n",
2911                         ch >= ' ' ? ch : '.', ch, m,
2912                         dest->quote, ctx->stack == NULL ? '*' : '.');
2913
2914                 if (m==0 || ((m==1 || m==2) && dest->quote)) {
2915                         b_addqchr(dest, ch, dest->quote);
2916                 } else {
2917                         if (m==2) {  /* unquoted IFS */
2918                                 if (done_word(dest, ctx)) {
2919                                         return 1;
2920                                 }
2921                                 /* If we aren't performing a substitution, treat a newline as a
2922                                  * command separator.  */
2923                                 if (end_trigger != '\0' && ch=='\n')
2924                                         done_pipe(ctx,PIPE_SEQ);
2925                         }
2926                         if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2927                                 debug_printf("leaving parse_stream (triggered)\n");
2928                                 return 0;
2929                         }
2930 #if 0
2931                         if (ch=='\n') {
2932                                 /* Yahoo!  Time to run with it! */
2933                                 done_pipe(ctx,PIPE_SEQ);
2934                                 run_list(ctx->list_head);
2935                                 initialize_context(ctx);
2936                         }
2937 #endif
2938                         if (m!=2) switch (ch) {
2939                 case '#':
2940                         if (dest->length == 0 && !dest->quote) {
2941                                 while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
2942                         } else {
2943                                 b_addqchr(dest, ch, dest->quote);
2944                         }
2945                         break;
2946                 case '\\':
2947                         if (next == EOF) {
2948                                 syntax();
2949                                 return 1;
2950                         }
2951                         b_addqchr(dest, '\\', dest->quote);
2952                         b_addqchr(dest, b_getch(input), dest->quote);
2953                         break;
2954                 case '$':
2955                         if (handle_dollar(dest, ctx, input)!=0) return 1;
2956                         break;
2957                 case '\'':
2958                         dest->nonnull = 1;
2959                         while(ch=b_getch(input),ch!=EOF && ch!='\'') {
2960 #ifdef __U_BOOT__
2961                                 if(input->__promptme == 0) return 1;
2962 #endif
2963                                 b_addchr(dest,ch);
2964                         }
2965                         if (ch==EOF) {
2966                                 syntax();
2967                                 return 1;
2968                         }
2969                         break;
2970                 case '"':
2971                         dest->nonnull = 1;
2972                         dest->quote = !dest->quote;
2973                         break;
2974 #ifndef __U_BOOT__
2975                 case '`':
2976                         process_command_subs(dest, ctx, input, '`');
2977                         break;
2978                 case '>':
2979                         redir_fd = redirect_opt_num(dest);
2980                         done_word(dest, ctx);
2981                         redir_style=REDIRECT_OVERWRITE;
2982                         if (next == '>') {
2983                                 redir_style=REDIRECT_APPEND;
2984                                 b_getch(input);
2985                         } else if (next == '(') {
2986                                 syntax();   /* until we support >(list) Process Substitution */
2987                                 return 1;
2988                         }
2989                         setup_redirect(ctx, redir_fd, redir_style, input);
2990                         break;
2991                 case '<':
2992                         redir_fd = redirect_opt_num(dest);
2993                         done_word(dest, ctx);
2994                         redir_style=REDIRECT_INPUT;
2995                         if (next == '<') {
2996                                 redir_style=REDIRECT_HEREIS;
2997                                 b_getch(input);
2998                         } else if (next == '>') {
2999                                 redir_style=REDIRECT_IO;
3000                                 b_getch(input);
3001                         } else if (next == '(') {
3002                                 syntax();   /* until we support <(list) Process Substitution */
3003                                 return 1;
3004                         }
3005                         setup_redirect(ctx, redir_fd, redir_style, input);
3006                         break;
3007 #endif
3008                 case ';':
3009                         done_word(dest, ctx);
3010                         done_pipe(ctx,PIPE_SEQ);
3011                         break;
3012                 case '&':
3013                         done_word(dest, ctx);
3014                         if (next=='&') {
3015                                 b_getch(input);
3016                                 done_pipe(ctx,PIPE_AND);
3017                         } else {
3018 #ifndef __U_BOOT__
3019                                 done_pipe(ctx,PIPE_BG);
3020 #else
3021                                 syntax_err();
3022                                 return 1;
3023 #endif
3024                         }
3025                         break;
3026                 case '|':
3027                         done_word(dest, ctx);
3028                         if (next=='|') {
3029                                 b_getch(input);
3030                                 done_pipe(ctx,PIPE_OR);
3031                         } else {
3032                                 /* we could pick up a file descriptor choice here
3033                                  * with redirect_opt_num(), but bash doesn't do it.
3034                                  * "echo foo 2| cat" yields "foo 2". */
3035 #ifndef __U_BOOT__
3036                                 done_command(ctx);
3037 #else
3038                                 syntax_err();
3039                                 return 1;
3040 #endif
3041                         }
3042                         break;
3043 #ifndef __U_BOOT__
3044                 case '(':
3045                 case '{':
3046                         if (parse_group(dest, ctx, input, ch)!=0) return 1;
3047                         break;
3048                 case ')':
3049                 case '}':
3050                         syntax();   /* Proper use of this character caught by end_trigger */
3051                         return 1;
3052                         break;
3053 #endif
3054                 default:
3055                         syntax();   /* this is really an internal logic error */
3056                         return 1;
3057                         }
3058                 }
3059         }
3060         /* complain if quote?  No, maybe we just finished a command substitution
3061          * that was quoted.  Example:
3062          * $ echo "`cat foo` plus more"
3063          * and we just got the EOF generated by the subshell that ran "cat foo"
3064          * The only real complaint is if we got an EOF when end_trigger != '\0',
3065          * that is, we were really supposed to get end_trigger, and never got
3066          * one before the EOF.  Can't use the standard "syntax error" return code,
3067          * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
3068         debug_printf("leaving parse_stream (EOF)\n");
3069         if (end_trigger != '\0') return -1;
3070         return 0;
3071 }
3072
3073 void mapset(const unsigned char *set, int code)
3074 {
3075         const unsigned char *s;
3076         for (s=set; *s; s++) map[*s] = code;
3077 }
3078
3079 void update_ifs_map(void)
3080 {
3081         /* char *ifs and char map[256] are both globals. */
3082         ifs = (uchar *)getenv("IFS");
3083         if (ifs == NULL) ifs=(uchar *)" \t\n";
3084         /* Precompute a list of 'flow through' behavior so it can be treated
3085          * quickly up front.  Computation is necessary because of IFS.
3086          * Special case handling of IFS == " \t\n" is not implemented.
3087          * The map[] array only really needs two bits each, and on most machines
3088          * that would be faster because of the reduced L1 cache footprint.
3089          */
3090         memset(map,0,sizeof(map)); /* most characters flow through always */
3091 #ifndef __U_BOOT__
3092         mapset((uchar *)"\\$'\"`", 3);      /* never flow through */
3093         mapset((uchar *)"<>;&|(){}#", 1);   /* flow through if quoted */
3094 #else
3095         mapset((uchar *)"\\$'\"", 3);       /* never flow through */
3096         mapset((uchar *)";&|#", 1);         /* flow through if quoted */
3097 #endif
3098         mapset(ifs, 2);            /* also flow through if quoted */
3099 }
3100
3101 /* most recursion does not come through here, the exeception is
3102  * from builtin_source() */
3103 int parse_stream_outer(struct in_str *inp, int flag)
3104 {
3105
3106         struct p_context ctx;
3107         o_string temp=NULL_O_STRING;
3108         int rcode;
3109 #ifdef __U_BOOT__
3110         int code = 0;
3111 #endif
3112         do {
3113                 ctx.type = flag;
3114                 initialize_context(&ctx);
3115                 update_ifs_map();
3116                 if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset((uchar *)";$&|", 0);
3117                 inp->promptmode=1;
3118                 rcode = parse_stream(&temp, &ctx, inp, '\n');
3119 #ifdef __U_BOOT__
3120                 if (rcode == 1) flag_repeat = 0;
3121 #endif
3122                 if (rcode != 1 && ctx.old_flag != 0) {
3123                         syntax();
3124 #ifdef __U_BOOT__
3125                         flag_repeat = 0;
3126 #endif
3127                 }
3128                 if (rcode != 1 && ctx.old_flag == 0) {
3129                         done_word(&temp, &ctx);
3130                         done_pipe(&ctx,PIPE_SEQ);
3131 #ifndef __U_BOOT__
3132                         run_list(ctx.list_head);
3133 #else
3134                         code = run_list(ctx.list_head);
3135                         if (code == -2) {       /* exit */
3136                                 b_free(&temp);
3137                                 code = 0;
3138                                 /* XXX hackish way to not allow exit from main loop */
3139                                 if (inp->peek == file_peek) {
3140                                         printf("exit not allowed from main input shell.\n");
3141                                         continue;
3142                                 }
3143                                 break;
3144                         }
3145                         if (code == -1)
3146                             flag_repeat = 0;
3147 #endif
3148                 } else {
3149                         if (ctx.old_flag != 0) {
3150                                 free(ctx.stack);
3151                                 b_reset(&temp);
3152                         }
3153 #ifdef __U_BOOT__
3154                         if (inp->__promptme == 0) printf("<INTERRUPT>\n");
3155                         inp->__promptme = 1;
3156 #endif
3157                         temp.nonnull = 0;
3158                         temp.quote = 0;
3159                         inp->p = NULL;
3160                         free_pipe_list(ctx.list_head,0);
3161                 }
3162                 b_free(&temp);
3163         } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP));   /* loop on syntax errors, return on EOF */
3164 #ifndef __U_BOOT__
3165         return 0;
3166 #else
3167         return (code != 0) ? 1 : 0;
3168 #endif /* __U_BOOT__ */
3169 }
3170
3171 #ifndef __U_BOOT__
3172 static int parse_string_outer(const char *s, int flag)
3173 #else
3174 int parse_string_outer(const char *s, int flag)
3175 #endif  /* __U_BOOT__ */
3176 {
3177         struct in_str input;
3178 #ifdef __U_BOOT__
3179         char *p = NULL;
3180         int rcode;
3181         if ( !s || !*s)
3182                 return 1;
3183         if (!(p = strchr(s, '\n')) || *++p) {
3184                 p = xmalloc(strlen(s) + 2);
3185                 strcpy(p, s);
3186                 strcat(p, "\n");
3187                 setup_string_in_str(&input, p);
3188                 rcode = parse_stream_outer(&input, flag);
3189                 free(p);
3190                 return rcode;
3191         } else {
3192 #endif
3193         setup_string_in_str(&input, s);
3194         return parse_stream_outer(&input, flag);
3195 #ifdef __U_BOOT__
3196         }
3197 #endif
3198 }
3199
3200 #ifndef __U_BOOT__
3201 static int parse_file_outer(FILE *f)
3202 #else
3203 int parse_file_outer(void)
3204 #endif
3205 {
3206         int rcode;
3207         struct in_str input;
3208 #ifndef __U_BOOT__
3209         setup_file_in_str(&input, f);
3210 #else
3211         setup_file_in_str(&input);
3212 #endif
3213         rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
3214         return rcode;
3215 }
3216
3217 #ifdef __U_BOOT__
3218 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3219 static void u_boot_hush_reloc(void)
3220 {
3221         unsigned long addr;
3222         struct reserved_combo *r;
3223
3224         for (r=reserved_list; r<reserved_list+NRES; r++) {
3225                 addr = (ulong) (r->literal) + gd->reloc_off;
3226                 r->literal = (char *)addr;
3227         }
3228 }
3229 #endif
3230
3231 int u_boot_hush_start(void)
3232 {
3233         if (top_vars == NULL) {
3234                 top_vars = malloc(sizeof(struct variables));
3235                 top_vars->name = "HUSH_VERSION";
3236                 top_vars->value = "0.01";
3237                 top_vars->next = 0;
3238                 top_vars->flg_export = 0;
3239                 top_vars->flg_read_only = 1;
3240 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3241                 u_boot_hush_reloc();
3242 #endif
3243         }
3244         return 0;
3245 }
3246
3247 static void *xmalloc(size_t size)
3248 {
3249         void *p = NULL;
3250
3251         if (!(p = malloc(size))) {
3252             printf("ERROR : memory not allocated\n");
3253             for(;;);
3254         }
3255         return p;
3256 }
3257
3258 static void *xrealloc(void *ptr, size_t size)
3259 {
3260         void *p = NULL;
3261
3262         if (!(p = realloc(ptr, size))) {
3263             printf("ERROR : memory not allocated\n");
3264             for(;;);
3265         }
3266         return p;
3267 }
3268 #endif /* __U_BOOT__ */
3269
3270 #ifndef __U_BOOT__
3271 /* Make sure we have a controlling tty.  If we get started under a job
3272  * aware app (like bash for example), make sure we are now in charge so
3273  * we don't fight over who gets the foreground */
3274 static void setup_job_control(void)
3275 {
3276         static pid_t shell_pgrp;
3277         /* Loop until we are in the foreground.  */
3278         while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
3279                 kill (- shell_pgrp, SIGTTIN);
3280
3281         /* Ignore interactive and job-control signals.  */
3282         signal(SIGINT, SIG_IGN);
3283         signal(SIGQUIT, SIG_IGN);
3284         signal(SIGTERM, SIG_IGN);
3285         signal(SIGTSTP, SIG_IGN);
3286         signal(SIGTTIN, SIG_IGN);
3287         signal(SIGTTOU, SIG_IGN);
3288         signal(SIGCHLD, SIG_IGN);
3289
3290         /* Put ourselves in our own process group.  */
3291         setsid();
3292         shell_pgrp = getpid ();
3293         setpgid (shell_pgrp, shell_pgrp);
3294
3295         /* Grab control of the terminal.  */
3296         tcsetpgrp(shell_terminal, shell_pgrp);
3297 }
3298
3299 int hush_main(int argc, char * const *argv)
3300 {
3301         int opt;
3302         FILE *input;
3303         char **e = environ;
3304
3305         /* XXX what should these be while sourcing /etc/profile? */
3306         global_argc = argc;
3307         global_argv = argv;
3308
3309         /* (re?) initialize globals.  Sometimes hush_main() ends up calling
3310          * hush_main(), therefore we cannot rely on the BSS to zero out this
3311          * stuff.  Reset these to 0 every time. */
3312         ifs = NULL;
3313         /* map[] is taken care of with call to update_ifs_map() */
3314         fake_mode = 0;
3315         interactive = 0;
3316         close_me_head = NULL;
3317         last_bg_pid = 0;
3318         job_list = NULL;
3319         last_jobid = 0;
3320
3321         /* Initialize some more globals to non-zero values */
3322         set_cwd();
3323 #ifdef CONFIG_FEATURE_COMMAND_EDITING
3324         cmdedit_set_initial_prompt();
3325 #else
3326         PS1 = NULL;
3327 #endif
3328         PS2 = "> ";
3329
3330         /* initialize our shell local variables with the values
3331          * currently living in the environment */
3332         if (e) {
3333                 for (; *e; e++)
3334                         set_local_var(*e, 2);   /* without call putenv() */
3335         }
3336
3337         last_return_code=EXIT_SUCCESS;
3338
3339
3340         if (argv[0] && argv[0][0] == '-') {
3341                 debug_printf("\nsourcing /etc/profile\n");
3342                 if ((input = fopen("/etc/profile", "r")) != NULL) {
3343                         mark_open(fileno(input));
3344                         parse_file_outer(input);
3345                         mark_closed(fileno(input));
3346                         fclose(input);
3347                 }
3348         }
3349         input=stdin;
3350
3351         while ((opt = getopt(argc, argv, "c:xif")) > 0) {
3352                 switch (opt) {
3353                         case 'c':
3354                                 {
3355                                         global_argv = argv+optind;
3356                                         global_argc = argc-optind;
3357                                         opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
3358                                         goto final_return;
3359                                 }
3360                                 break;
3361                         case 'i':
3362                                 interactive++;
3363                                 break;
3364                         case 'f':
3365                                 fake_mode++;
3366                                 break;
3367                         default:
3368 #ifndef BB_VER
3369                                 fprintf(stderr, "Usage: sh [FILE]...\n"
3370                                                 "   or: sh -c command [args]...\n\n");
3371                                 exit(EXIT_FAILURE);
3372 #else
3373                                 show_usage();
3374 #endif
3375                 }
3376         }
3377         /* A shell is interactive if the `-i' flag was given, or if all of
3378          * the following conditions are met:
3379          *        no -c command
3380          *    no arguments remaining or the -s flag given
3381          *    standard input is a terminal
3382          *    standard output is a terminal
3383          *    Refer to Posix.2, the description of the `sh' utility. */
3384         if (argv[optind]==NULL && input==stdin &&
3385                         isatty(fileno(stdin)) && isatty(fileno(stdout))) {
3386                 interactive++;
3387         }
3388
3389         debug_printf("\ninteractive=%d\n", interactive);
3390         if (interactive) {
3391                 /* Looks like they want an interactive shell */
3392 #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
3393                 printf( "\n\n" BB_BANNER " hush - the humble shell v0.01 (testing)\n");
3394                 printf( "Enter 'help' for a list of built-in commands.\n\n");
3395 #endif
3396                 setup_job_control();
3397         }
3398
3399         if (argv[optind]==NULL) {
3400                 opt=parse_file_outer(stdin);
3401                 goto final_return;
3402         }
3403
3404         debug_printf("\nrunning script '%s'\n", argv[optind]);
3405         global_argv = argv+optind;
3406         global_argc = argc-optind;
3407         input = xfopen(argv[optind], "r");
3408         opt = parse_file_outer(input);
3409
3410 #ifdef CONFIG_FEATURE_CLEAN_UP
3411         fclose(input);
3412         if (cwd && cwd != unknown)
3413                 free((char*)cwd);
3414         {
3415                 struct variables *cur, *tmp;
3416                 for(cur = top_vars; cur; cur = tmp) {
3417                         tmp = cur->next;
3418                         if (!cur->flg_read_only) {
3419                                 free(cur->name);
3420                                 free(cur->value);
3421                                 free(cur);
3422                         }
3423                 }
3424         }
3425 #endif
3426
3427 final_return:
3428         return(opt?opt:last_return_code);
3429 }
3430 #endif
3431
3432 static char *insert_var_value(char *inp)
3433 {
3434         int res_str_len = 0;
3435         int len;
3436         int done = 0;
3437         char *p, *p1, *res_str = NULL;
3438
3439         while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
3440                 if (p != inp) {
3441                         len = p - inp;
3442                         res_str = xrealloc(res_str, (res_str_len + len));
3443                         strncpy((res_str + res_str_len), inp, len);
3444                         res_str_len += len;
3445                 }
3446                 inp = ++p;
3447                 p = strchr(inp, SPECIAL_VAR_SYMBOL);
3448                 *p = '\0';
3449                 if ((p1 = lookup_param(inp))) {
3450                         len = res_str_len + strlen(p1);
3451                         res_str = xrealloc(res_str, (1 + len));
3452                         strcpy((res_str + res_str_len), p1);
3453                         res_str_len = len;
3454                 }
3455                 *p = SPECIAL_VAR_SYMBOL;
3456                 inp = ++p;
3457                 done = 1;
3458         }
3459         if (done) {
3460                 res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
3461                 strcpy((res_str + res_str_len), inp);
3462                 while ((p = strchr(res_str, '\n'))) {
3463                         *p = ' ';
3464                 }
3465         }
3466         return (res_str == NULL) ? inp : res_str;
3467 }
3468
3469 static char **make_list_in(char **inp, char *name)
3470 {
3471         int len, i;
3472         int name_len = strlen(name);
3473         int n = 0;
3474         char **list;
3475         char *p1, *p2, *p3;
3476
3477         /* create list of variable values */
3478         list = xmalloc(sizeof(*list));
3479         for (i = 0; inp[i]; i++) {
3480                 p3 = insert_var_value(inp[i]);
3481                 p1 = p3;
3482                 while (*p1) {
3483                         if ((*p1 == ' ')) {
3484                                 p1++;
3485                                 continue;
3486                         }
3487                         if ((p2 = strchr(p1, ' '))) {
3488                                 len = p2 - p1;
3489                         } else {
3490                                 len = strlen(p1);
3491                                 p2 = p1 + len;
3492                         }
3493                         /* we use n + 2 in realloc for list,because we add
3494                          * new element and then we will add NULL element */
3495                         list = xrealloc(list, sizeof(*list) * (n + 2));
3496                         list[n] = xmalloc(2 + name_len + len);
3497                         strcpy(list[n], name);
3498                         strcat(list[n], "=");
3499                         strncat(list[n], p1, len);
3500                         list[n++][name_len + len + 1] = '\0';
3501                         p1 = p2;
3502                 }
3503                 if (p3 != inp[i]) free(p3);
3504         }
3505         list[n] = NULL;
3506         return list;
3507 }
3508
3509 /* Make new string for parser */
3510 static char * make_string(char ** inp)
3511 {
3512         char *p;
3513         char *str = NULL;
3514         int n;
3515         int len = 2;
3516
3517         for (n = 0; inp[n]; n++) {
3518                 p = insert_var_value(inp[n]);
3519                 str = xrealloc(str, (len + strlen(p)));
3520                 if (n) {
3521                         strcat(str, " ");
3522                 } else {
3523                         *str = '\0';
3524                 }
3525                 strcat(str, p);
3526                 len = strlen(str) + 3;
3527                 if (p != inp[n]) free(p);
3528         }
3529         len = strlen(str);
3530         *(str + len) = '\n';
3531         *(str + len + 1) = '\0';
3532         return str;
3533 }
3534
3535 #ifdef __U_BOOT__
3536 int do_showvar (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
3537 {
3538         int i, k;
3539         int rcode = 0;
3540         struct variables *cur;
3541
3542         if (argc == 1) {                /* Print all env variables      */
3543                 for (cur = top_vars; cur; cur = cur->next) {
3544                         printf ("%s=%s\n", cur->name, cur->value);
3545                         if (ctrlc ()) {
3546                                 puts ("\n ** Abort\n");
3547                                 return 1;
3548                         }
3549                 }
3550                 return 0;
3551         }
3552         for (i = 1; i < argc; ++i) {    /* print single env variables   */
3553                 char *name = argv[i];
3554
3555                 k = -1;
3556                 for (cur = top_vars; cur; cur = cur->next) {
3557                         if(strcmp (cur->name, name) == 0) {
3558                                 k = 0;
3559                                 printf ("%s=%s\n", cur->name, cur->value);
3560                         }
3561                         if (ctrlc ()) {
3562                                 puts ("\n ** Abort\n");
3563                                 return 1;
3564                         }
3565                 }
3566                 if (k < 0) {
3567                         printf ("## Error: \"%s\" not defined\n", name);
3568                         rcode ++;
3569                 }
3570         }
3571         return rcode;
3572 }
3573
3574 U_BOOT_CMD(
3575         showvar, CONFIG_SYS_MAXARGS, 1, do_showvar,
3576         "print local hushshell variables",
3577         "\n    - print values of all hushshell variables\n"
3578         "showvar name ...\n"
3579         "    - print value of hushshell variable 'name'"
3580 );
3581
3582 #endif
3583 /****************************************************************************/