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  *      simple_itoa() was lifted from boa-0.93.15
21  *      b_addchr() derived from similar w_addchar function in glibc-2.2
22  *      setup_redirect(), redirect_opt_num(), and big chunks of main()
23  *        and many builtins derived from contributions by Erik Andersen
24  *      miscellaneous bugfixes from Matt Kraai
25  *
26  * There are two big (and related) architecture differences between
27  * this parser and the lash parser.  One is that this version is
28  * actually designed from the ground up to understand nearly all
29  * of the Bourne grammar.  The second, consequential change is that
30  * the parser and input reader have been turned inside out.  Now,
31  * the parser is in control, and asks for input as needed.  The old
32  * way had the input reader in control, and it asked for parsing to
33  * take place as needed.  The new way makes it much easier to properly
34  * handle the recursion implicit in the various substitutions, especially
35  * across continuation lines.
36  *
37  * Bash grammar not implemented: (how many of these were in original sh?)
38  *      $@ (those sure look like weird quoting rules)
39  *      $_
40  *      ! negation operator for pipes
41  *      &> and >& redirection of stdout+stderr
42  *      Brace Expansion
43  *      Tilde Expansion
44  *      fancy forms of Parameter Expansion
45  *      aliases
46  *      Arithmetic Expansion
47  *      <(list) and >(list) Process Substitution
48  *      reserved words: case, esac, select, function
49  *      Here Documents ( << word )
50  *      Functions
51  * Major bugs:
52  *      job handling woefully incomplete and buggy
53  *      reserved word execution woefully incomplete and buggy
54  * to-do:
55  *      port selected bugfixes from post-0.49 busybox lash - done?
56  *      finish implementing reserved words: for, while, until, do, done
57  *      change { and } from special chars to reserved words
58  *      builtins: break, continue, eval, return, set, trap, ulimit
59  *      test magic exec
60  *      handle children going into background
61  *      clean up recognition of null pipes
62  *      check setting of global_argc and global_argv
63  *      control-C handling, probably with longjmp
64  *      follow IFS rules more precisely, including update semantics
65  *      figure out what to do with backslash-newline
66  *      explain why we use signal instead of sigaction
67  *      propagate syntax errors, die on resource errors?
68  *      continuation lines, both explicit and implicit - done?
69  *      memory leak finding and plugging - done?
70  *      more testing, especially quoting rules and redirection
71  *      document how quoting rules not precisely followed for variable assignments
72  *      maybe change map[] to use 2-bit entries
73  *      (eventually) remove all the printf's
74  *
75  * This program is free software; you can redistribute it and/or modify
76  * it under the terms of the GNU General Public License as published by
77  * the Free Software Foundation; either version 2 of the License, or
78  * (at your option) any later version.
79  *
80  * This program is distributed in the hope that it will be useful,
81  * but WITHOUT ANY WARRANTY; without even the implied warranty of
82  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
83  * General Public License for more details.
84  *
85  * You should have received a copy of the GNU General Public License
86  * along with this program; if not, write to the Free Software
87  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
88  */
89 #define __U_BOOT__
90 #ifdef __U_BOOT__
91 #include <malloc.h>         /* malloc, free, realloc*/
92 #include <linux/ctype.h>    /* isalpha, isdigit */
93 #include <common.h>        /* readline */
94 #include <hush.h>
95 #include <command.h>        /* find_cmd */
96 /*cmd_boot.c*/
97 extern int do_bootd (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]);      /* do_bootd */
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__
debug_printf(const char * format,...)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
debug_printf(const char * format,...)380 static inline void debug_printf(const char *format, ...) { }
381 #endif
382 #define final_printf debug_printf
383 
384 #ifdef __U_BOOT__
syntax_err(void)385 static void syntax_err(void) {
386 	 printf("syntax error\n");
387 }
388 #else
__syntax(char * file,int line)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 static char *get_local_var(const char *var);
503 
504 #ifndef __U_BOOT__
505 /* Table of built-in functions.  They can be forked or not, depending on
506  * context: within pipes, they fork.  As simple commands, they do not.
507  * When used in non-forking context, they can change global variables
508  * in the parent shell process.  If forked, of course they can not.
509  * For example, 'unset foo | whatever' will parse and run, but foo will
510  * still be set at the end. */
511 static struct built_in_command bltins[] = {
512 	{"bg", "Resume a job in the background", builtin_fg_bg},
513 	{"break", "Exit for, while or until loop", builtin_not_written},
514 	{"cd", "Change working directory", builtin_cd},
515 	{"continue", "Continue for, while or until loop", builtin_not_written},
516 	{"env", "Print all environment variables", builtin_env},
517 	{"eval", "Construct and run shell command", builtin_eval},
518 	{"exec", "Exec command, replacing this shell with the exec'd process",
519 		builtin_exec},
520 	{"exit", "Exit from shell()", builtin_exit},
521 	{"export", "Set environment variable", builtin_export},
522 	{"fg", "Bring job into the foreground", builtin_fg_bg},
523 	{"jobs", "Lists the active jobs", builtin_jobs},
524 	{"pwd", "Print current directory", builtin_pwd},
525 	{"read", "Input environment variable", builtin_read},
526 	{"return", "Return from a function", builtin_not_written},
527 	{"set", "Set/unset shell local variables", builtin_set},
528 	{"shift", "Shift positional parameters", builtin_shift},
529 	{"trap", "Trap signals", builtin_not_written},
530 	{"ulimit","Controls resource limits", builtin_not_written},
531 	{"umask","Sets file creation mask", builtin_umask},
532 	{"unset", "Unset environment variable", builtin_unset},
533 	{".", "Source-in and run commands in a file", builtin_source},
534 	{"help", "List shell built-in commands", builtin_help},
535 	{NULL, NULL, NULL}
536 };
537 
set_cwd(void)538 static const char *set_cwd(void)
539 {
540 	if(cwd==unknown)
541 		cwd = NULL;     /* xgetcwd(arg) called free(arg) */
542 	cwd = xgetcwd((char *)cwd);
543 	if (!cwd)
544 		cwd = unknown;
545 	return cwd;
546 }
547 
548 /* built-in 'eval' handler */
builtin_eval(struct child_prog * child)549 static int builtin_eval(struct child_prog *child)
550 {
551 	char *str = NULL;
552 	int rcode = EXIT_SUCCESS;
553 
554 	if (child->argv[1]) {
555 		str = make_string(child->argv + 1);
556 		parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
557 					FLAG_PARSE_SEMICOLON);
558 		free(str);
559 		rcode = last_return_code;
560 	}
561 	return rcode;
562 }
563 
564 /* built-in 'cd <path>' handler */
builtin_cd(struct child_prog * child)565 static int builtin_cd(struct child_prog *child)
566 {
567 	char *newdir;
568 	if (child->argv[1] == NULL)
569 		newdir = getenv("HOME");
570 	else
571 		newdir = child->argv[1];
572 	if (chdir(newdir)) {
573 		printf("cd: %s: %s\n", newdir, strerror(errno));
574 		return EXIT_FAILURE;
575 	}
576 	set_cwd();
577 	return EXIT_SUCCESS;
578 }
579 
580 /* built-in 'env' handler */
builtin_env(struct child_prog * dummy)581 static int builtin_env(struct child_prog *dummy)
582 {
583 	char **e = environ;
584 	if (e == NULL) return EXIT_FAILURE;
585 	for (; *e; e++) {
586 		puts(*e);
587 	}
588 	return EXIT_SUCCESS;
589 }
590 
591 /* built-in 'exec' handler */
builtin_exec(struct child_prog * child)592 static int builtin_exec(struct child_prog *child)
593 {
594 	if (child->argv[1] == NULL)
595 		return EXIT_SUCCESS;   /* Really? */
596 	child->argv++;
597 	pseudo_exec(child);
598 	/* never returns */
599 }
600 
601 /* built-in 'exit' handler */
builtin_exit(struct child_prog * child)602 static int builtin_exit(struct child_prog *child)
603 {
604 	if (child->argv[1] == NULL)
605 		exit(last_return_code);
606 	exit (atoi(child->argv[1]));
607 }
608 
609 /* built-in 'export VAR=value' handler */
builtin_export(struct child_prog * child)610 static int builtin_export(struct child_prog *child)
611 {
612 	int res = 0;
613 	char *name = child->argv[1];
614 
615 	if (name == NULL) {
616 		return (builtin_env(child));
617 	}
618 
619 	name = strdup(name);
620 
621 	if(name) {
622 		char *value = strchr(name, '=');
623 
624 		if (!value) {
625 			char *tmp;
626 			/* They are exporting something without an =VALUE */
627 
628 			value = get_local_var(name);
629 			if (value) {
630 				size_t ln = strlen(name);
631 
632 				tmp = realloc(name, ln+strlen(value)+2);
633 				if(tmp==NULL)
634 					res = -1;
635 				else {
636 					sprintf(tmp+ln, "=%s", value);
637 					name = tmp;
638 				}
639 			} else {
640 				/* bash does not return an error when trying to export
641 				 * an undefined variable.  Do likewise. */
642 				res = 1;
643 			}
644 		}
645 	}
646 	if (res<0)
647 		perror_msg("export");
648 	else if(res==0)
649 		res = set_local_var(name, 1);
650 	else
651 		res = 0;
652 	free(name);
653 	return res;
654 }
655 
656 /* built-in 'fg' and 'bg' handler */
builtin_fg_bg(struct child_prog * child)657 static int builtin_fg_bg(struct child_prog *child)
658 {
659 	int i, jobnum;
660 	struct pipe *pi=NULL;
661 
662 	if (!interactive)
663 		return EXIT_FAILURE;
664 	/* If they gave us no args, assume they want the last backgrounded task */
665 	if (!child->argv[1]) {
666 		for (pi = job_list; pi; pi = pi->next) {
667 			if (pi->jobid == last_jobid) {
668 				break;
669 			}
670 		}
671 		if (!pi) {
672 			error_msg("%s: no current job", child->argv[0]);
673 			return EXIT_FAILURE;
674 		}
675 	} else {
676 		if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
677 			error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
678 			return EXIT_FAILURE;
679 		}
680 		for (pi = job_list; pi; pi = pi->next) {
681 			if (pi->jobid == jobnum) {
682 				break;
683 			}
684 		}
685 		if (!pi) {
686 			error_msg("%s: %d: no such job", child->argv[0], jobnum);
687 			return EXIT_FAILURE;
688 		}
689 	}
690 
691 	if (*child->argv[0] == 'f') {
692 		/* Put the job into the foreground.  */
693 		tcsetpgrp(shell_terminal, pi->pgrp);
694 	}
695 
696 	/* Restart the processes in the job */
697 	for (i = 0; i < pi->num_progs; i++)
698 		pi->progs[i].is_stopped = 0;
699 
700 	if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) {
701 		if (i == ESRCH) {
702 			remove_bg_job(pi);
703 		} else {
704 			perror_msg("kill (SIGCONT)");
705 		}
706 	}
707 
708 	pi->stopped_progs = 0;
709 	return EXIT_SUCCESS;
710 }
711 
712 /* built-in 'help' handler */
builtin_help(struct child_prog * dummy)713 static int builtin_help(struct child_prog *dummy)
714 {
715 	struct built_in_command *x;
716 
717 	printf("\nBuilt-in commands:\n");
718 	printf("-------------------\n");
719 	for (x = bltins; x->cmd; x++) {
720 		if (x->descr==NULL)
721 			continue;
722 		printf("%s\t%s\n", x->cmd, x->descr);
723 	}
724 	printf("\n\n");
725 	return EXIT_SUCCESS;
726 }
727 
728 /* built-in 'jobs' handler */
builtin_jobs(struct child_prog * child)729 static int builtin_jobs(struct child_prog *child)
730 {
731 	struct pipe *job;
732 	char *status_string;
733 
734 	for (job = job_list; job; job = job->next) {
735 		if (job->running_progs == job->stopped_progs)
736 			status_string = "Stopped";
737 		else
738 			status_string = "Running";
739 
740 		printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
741 	}
742 	return EXIT_SUCCESS;
743 }
744 
745 
746 /* built-in 'pwd' handler */
builtin_pwd(struct child_prog * dummy)747 static int builtin_pwd(struct child_prog *dummy)
748 {
749 	puts(set_cwd());
750 	return EXIT_SUCCESS;
751 }
752 
753 /* built-in 'read VAR' handler */
builtin_read(struct child_prog * child)754 static int builtin_read(struct child_prog *child)
755 {
756 	int res;
757 
758 	if (child->argv[1]) {
759 		char string[BUFSIZ];
760 		char *var = 0;
761 
762 		string[0] = 0;  /* In case stdin has only EOF */
763 		/* read string */
764 		fgets(string, sizeof(string), stdin);
765 		chomp(string);
766 		var = malloc(strlen(child->argv[1])+strlen(string)+2);
767 		if(var) {
768 			sprintf(var, "%s=%s", child->argv[1], string);
769 			res = set_local_var(var, 0);
770 		} else
771 			res = -1;
772 		if (res)
773 			fprintf(stderr, "read: %m\n");
774 		free(var);      /* So not move up to avoid breaking errno */
775 		return res;
776 	} else {
777 		do res=getchar(); while(res!='\n' && res!=EOF);
778 		return 0;
779 	}
780 }
781 
782 /* built-in 'set VAR=value' handler */
builtin_set(struct child_prog * child)783 static int builtin_set(struct child_prog *child)
784 {
785 	char *temp = child->argv[1];
786 	struct variables *e;
787 
788 	if (temp == NULL)
789 		for(e = top_vars; e; e=e->next)
790 			printf("%s=%s\n", e->name, e->value);
791 	else
792 		set_local_var(temp, 0);
793 
794 		return EXIT_SUCCESS;
795 }
796 
797 
798 /* Built-in 'shift' handler */
builtin_shift(struct child_prog * child)799 static int builtin_shift(struct child_prog *child)
800 {
801 	int n=1;
802 	if (child->argv[1]) {
803 		n=atoi(child->argv[1]);
804 	}
805 	if (n>=0 && n<global_argc) {
806 		/* XXX This probably breaks $0 */
807 		global_argc -= n;
808 		global_argv += n;
809 		return EXIT_SUCCESS;
810 	} else {
811 		return EXIT_FAILURE;
812 	}
813 }
814 
815 /* Built-in '.' handler (read-in and execute commands from file) */
builtin_source(struct child_prog * child)816 static int builtin_source(struct child_prog *child)
817 {
818 	FILE *input;
819 	int status;
820 
821 	if (child->argv[1] == NULL)
822 		return EXIT_FAILURE;
823 
824 	/* XXX search through $PATH is missing */
825 	input = fopen(child->argv[1], "r");
826 	if (!input) {
827 		error_msg("Couldn't open file '%s'", child->argv[1]);
828 		return EXIT_FAILURE;
829 	}
830 
831 	/* Now run the file */
832 	/* XXX argv and argc are broken; need to save old global_argv
833 	 * (pointer only is OK!) on this stack frame,
834 	 * set global_argv=child->argv+1, recurse, and restore. */
835 	mark_open(fileno(input));
836 	status = parse_file_outer(input);
837 	mark_closed(fileno(input));
838 	fclose(input);
839 	return (status);
840 }
841 
builtin_umask(struct child_prog * child)842 static int builtin_umask(struct child_prog *child)
843 {
844 	mode_t new_umask;
845 	const char *arg = child->argv[1];
846 	char *end;
847 	if (arg) {
848 		new_umask=strtoul(arg, &end, 8);
849 		if (*end!='\0' || end == arg) {
850 			return EXIT_FAILURE;
851 		}
852 	} else {
853 		printf("%.3o\n", (unsigned int) (new_umask=umask(0)));
854 	}
855 	umask(new_umask);
856 	return EXIT_SUCCESS;
857 }
858 
859 /* built-in 'unset VAR' handler */
builtin_unset(struct child_prog * child)860 static int builtin_unset(struct child_prog *child)
861 {
862 	/* bash returned already true */
863 	unset_local_var(child->argv[1]);
864 	return EXIT_SUCCESS;
865 }
866 
builtin_not_written(struct child_prog * child)867 static int builtin_not_written(struct child_prog *child)
868 {
869 	printf("builtin_%s not written\n",child->argv[0]);
870 	return EXIT_FAILURE;
871 }
872 #endif
873 
b_check_space(o_string * o,int len)874 static int b_check_space(o_string *o, int len)
875 {
876 	/* It would be easy to drop a more restrictive policy
877 	 * in here, such as setting a maximum string length */
878 	if (o->length + len > o->maxlen) {
879 		char *old_data = o->data;
880 		/* assert (data == NULL || o->maxlen != 0); */
881 		o->maxlen += max(2*len, B_CHUNK);
882 		o->data = realloc(o->data, 1 + o->maxlen);
883 		if (o->data == NULL) {
884 			free(old_data);
885 		}
886 	}
887 	return o->data == NULL;
888 }
889 
b_addchr(o_string * o,int ch)890 static int b_addchr(o_string *o, int ch)
891 {
892 	debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
893 	if (b_check_space(o, 1)) return B_NOSPAC;
894 	o->data[o->length] = ch;
895 	o->length++;
896 	o->data[o->length] = '\0';
897 	return 0;
898 }
899 
b_reset(o_string * o)900 static void b_reset(o_string *o)
901 {
902 	o->length = 0;
903 	o->nonnull = 0;
904 	if (o->data != NULL) *o->data = '\0';
905 }
906 
b_free(o_string * o)907 static void b_free(o_string *o)
908 {
909 	b_reset(o);
910 	free(o->data);
911 	o->data = NULL;
912 	o->maxlen = 0;
913 }
914 
915 /* My analysis of quoting semantics tells me that state information
916  * is associated with a destination, not a source.
917  */
b_addqchr(o_string * o,int ch,int quote)918 static int b_addqchr(o_string *o, int ch, int quote)
919 {
920 	if (quote && strchr("*?[\\",ch)) {
921 		int rc;
922 		rc = b_addchr(o, '\\');
923 		if (rc) return rc;
924 	}
925 	return b_addchr(o, ch);
926 }
927 
928 /* belongs in utility.c */
simple_itoa(unsigned int i)929 char *simple_itoa(unsigned int i)
930 {
931 	/* 21 digits plus null terminator, good for 64-bit or smaller ints */
932 	static char local[22];
933 	char *p = &local[21];
934 	*p-- = '\0';
935 	do {
936 		*p-- = '0' + i % 10;
937 		i /= 10;
938 	} while (i > 0);
939 	return p + 1;
940 }
941 
942 #ifndef __U_BOOT__
b_adduint(o_string * o,unsigned int i)943 static int b_adduint(o_string *o, unsigned int i)
944 {
945 	int r;
946 	char *p = simple_itoa(i);
947 	/* no escape checking necessary */
948 	do r=b_addchr(o, *p++); while (r==0 && *p);
949 	return r;
950 }
951 #endif
952 
static_get(struct in_str * i)953 static int static_get(struct in_str *i)
954 {
955 	int ch = *i->p++;
956 	if (ch=='\0') return EOF;
957 	return ch;
958 }
959 
static_peek(struct in_str * i)960 static int static_peek(struct in_str *i)
961 {
962 	return *i->p;
963 }
964 
965 #ifndef __U_BOOT__
cmdedit_set_initial_prompt(void)966 static inline void cmdedit_set_initial_prompt(void)
967 {
968 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
969 	PS1 = NULL;
970 #else
971 	PS1 = getenv("PS1");
972 	if(PS1==0)
973 		PS1 = "\\w \\$ ";
974 #endif
975 }
976 
setup_prompt_string(int promptmode,char ** prompt_str)977 static inline void setup_prompt_string(int promptmode, char **prompt_str)
978 {
979 	debug_printf("setup_prompt_string %d ",promptmode);
980 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
981 	/* Set up the prompt */
982 	if (promptmode == 1) {
983 		free(PS1);
984 		PS1=xmalloc(strlen(cwd)+4);
985 		sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ?  "$ ":"# ");
986 		*prompt_str = PS1;
987 	} else {
988 		*prompt_str = PS2;
989 	}
990 #else
991 	*prompt_str = (promptmode==1)? PS1 : PS2;
992 #endif
993 	debug_printf("result %s\n",*prompt_str);
994 }
995 #endif
996 
get_user_input(struct in_str * i)997 static void get_user_input(struct in_str *i)
998 {
999 #ifndef __U_BOOT__
1000 	char *prompt_str;
1001 	static char the_command[BUFSIZ];
1002 
1003 	setup_prompt_string(i->promptmode, &prompt_str);
1004 #ifdef CONFIG_FEATURE_COMMAND_EDITING
1005 	/*
1006 	 ** enable command line editing only while a command line
1007 	 ** is actually being read; otherwise, we'll end up bequeathing
1008 	 ** atexit() handlers and other unwanted stuff to our
1009 	 ** child processes (rob@sysgo.de)
1010 	 */
1011 	cmdedit_read_input(prompt_str, the_command);
1012 #else
1013 	fputs(prompt_str, stdout);
1014 	fflush(stdout);
1015 	the_command[0]=fgetc(i->file);
1016 	the_command[1]='\0';
1017 #endif
1018 	fflush(stdout);
1019 	i->p = the_command;
1020 #else
1021 	extern char console_buffer[];
1022 	int n;
1023 	static char the_command[CONFIG_SYS_CBSIZE];
1024 
1025 #ifdef CONFIG_BOOT_RETRY_TIME
1026 #  ifdef CONFIG_RESET_TO_RETRY
1027 	extern int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]);
1028 #  else
1029 #	error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1030 #  endif
1031 	reset_cmd_timeout();
1032 #endif
1033 	i->__promptme = 1;
1034 	if (i->promptmode == 1) {
1035 		n = readline(CONFIG_SYS_PROMPT);
1036 	} else {
1037 		n = readline(CONFIG_SYS_PROMPT_HUSH_PS2);
1038 	}
1039 #ifdef CONFIG_BOOT_RETRY_TIME
1040 	if (n == -2) {
1041 	  puts("\nTimeout waiting for command\n");
1042 #  ifdef CONFIG_RESET_TO_RETRY
1043 	  do_reset(NULL, 0, 0, NULL);
1044 #  else
1045 #	error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1046 #  endif
1047 	}
1048 #endif
1049 	if (n == -1 ) {
1050 		flag_repeat = 0;
1051 		i->__promptme = 0;
1052 	}
1053 	n = strlen(console_buffer);
1054 	console_buffer[n] = '\n';
1055 	console_buffer[n+1]= '\0';
1056 	if (had_ctrlc()) flag_repeat = 0;
1057 	clear_ctrlc();
1058 	do_repeat = 0;
1059 	if (i->promptmode == 1) {
1060 		if (console_buffer[0] == '\n'&& flag_repeat == 0) {
1061 			strcpy(the_command,console_buffer);
1062 		}
1063 		else {
1064 			if (console_buffer[0] != '\n') {
1065 				strcpy(the_command,console_buffer);
1066 				flag_repeat = 1;
1067 			}
1068 			else {
1069 				do_repeat = 1;
1070 			}
1071 		}
1072 		i->p = the_command;
1073 	}
1074 	else {
1075 		if (console_buffer[0] != '\n') {
1076 			if (strlen(the_command) + strlen(console_buffer)
1077 			    < CONFIG_SYS_CBSIZE) {
1078 				n = strlen(the_command);
1079 				the_command[n-1] = ' ';
1080 				strcpy(&the_command[n],console_buffer);
1081 			}
1082 			else {
1083 				the_command[0] = '\n';
1084 				the_command[1] = '\0';
1085 				flag_repeat = 0;
1086 			}
1087 		}
1088 		if (i->__promptme == 0) {
1089 			the_command[0] = '\n';
1090 			the_command[1] = '\0';
1091 		}
1092 		i->p = console_buffer;
1093 	}
1094 #endif
1095 }
1096 
1097 /* This is the magic location that prints prompts
1098  * and gets data back from the user */
file_get(struct in_str * i)1099 static int file_get(struct in_str *i)
1100 {
1101 	int ch;
1102 
1103 	ch = 0;
1104 	/* If there is data waiting, eat it up */
1105 	if (i->p && *i->p) {
1106 		ch = *i->p++;
1107 	} else {
1108 		/* need to double check i->file because we might be doing something
1109 		 * more complicated by now, like sourcing or substituting. */
1110 #ifndef __U_BOOT__
1111 		if (i->__promptme && interactive && i->file == stdin) {
1112 			while(! i->p || (interactive && strlen(i->p)==0) ) {
1113 #else
1114 			while(! i->p  || strlen(i->p)==0 ) {
1115 #endif
1116 				get_user_input(i);
1117 			}
1118 			i->promptmode=2;
1119 #ifndef __U_BOOT__
1120 			i->__promptme = 0;
1121 #endif
1122 			if (i->p && *i->p) {
1123 				ch = *i->p++;
1124 			}
1125 #ifndef __U_BOOT__
1126 		} else {
1127 			ch = fgetc(i->file);
1128 		}
1129 
1130 #endif
1131 		debug_printf("b_getch: got a %d\n", ch);
1132 	}
1133 #ifndef __U_BOOT__
1134 	if (ch == '\n') i->__promptme=1;
1135 #endif
1136 	return ch;
1137 }
1138 
1139 /* All the callers guarantee this routine will never be
1140  * used right after a newline, so prompting is not needed.
1141  */
1142 static int file_peek(struct in_str *i)
1143 {
1144 #ifndef __U_BOOT__
1145 	if (i->p && *i->p) {
1146 #endif
1147 		return *i->p;
1148 #ifndef __U_BOOT__
1149 	} else {
1150 		i->peek_buf[0] = fgetc(i->file);
1151 		i->peek_buf[1] = '\0';
1152 		i->p = i->peek_buf;
1153 		debug_printf("b_peek: got a %d\n", *i->p);
1154 		return *i->p;
1155 	}
1156 #endif
1157 }
1158 
1159 #ifndef __U_BOOT__
1160 static void setup_file_in_str(struct in_str *i, FILE *f)
1161 #else
1162 static void setup_file_in_str(struct in_str *i)
1163 #endif
1164 {
1165 	i->peek = file_peek;
1166 	i->get = file_get;
1167 	i->__promptme=1;
1168 	i->promptmode=1;
1169 #ifndef __U_BOOT__
1170 	i->file = f;
1171 #endif
1172 	i->p = NULL;
1173 }
1174 
1175 static void setup_string_in_str(struct in_str *i, const char *s)
1176 {
1177 	i->peek = static_peek;
1178 	i->get = static_get;
1179 	i->__promptme=1;
1180 	i->promptmode=1;
1181 	i->p = s;
1182 }
1183 
1184 #ifndef __U_BOOT__
1185 static void mark_open(int fd)
1186 {
1187 	struct close_me *new = xmalloc(sizeof(struct close_me));
1188 	new->fd = fd;
1189 	new->next = close_me_head;
1190 	close_me_head = new;
1191 }
1192 
1193 static void mark_closed(int fd)
1194 {
1195 	struct close_me *tmp;
1196 	if (close_me_head == NULL || close_me_head->fd != fd)
1197 		error_msg_and_die("corrupt close_me");
1198 	tmp = close_me_head;
1199 	close_me_head = close_me_head->next;
1200 	free(tmp);
1201 }
1202 
1203 static void close_all(void)
1204 {
1205 	struct close_me *c;
1206 	for (c=close_me_head; c; c=c->next) {
1207 		close(c->fd);
1208 	}
1209 	close_me_head = NULL;
1210 }
1211 
1212 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1213  * and stderr if they are redirected. */
1214 static int setup_redirects(struct child_prog *prog, int squirrel[])
1215 {
1216 	int openfd, mode;
1217 	struct redir_struct *redir;
1218 
1219 	for (redir=prog->redirects; redir; redir=redir->next) {
1220 		if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1221 			/* something went wrong in the parse.  Pretend it didn't happen */
1222 			continue;
1223 		}
1224 		if (redir->dup == -1) {
1225 			mode=redir_table[redir->type].mode;
1226 			openfd = open(redir->word.gl_pathv[0], mode, 0666);
1227 			if (openfd < 0) {
1228 			/* this could get lost if stderr has been redirected, but
1229 			   bash and ash both lose it as well (though zsh doesn't!) */
1230 				perror_msg("error opening %s", redir->word.gl_pathv[0]);
1231 				return 1;
1232 			}
1233 		} else {
1234 			openfd = redir->dup;
1235 		}
1236 
1237 		if (openfd != redir->fd) {
1238 			if (squirrel && redir->fd < 3) {
1239 				squirrel[redir->fd] = dup(redir->fd);
1240 			}
1241 			if (openfd == -3) {
1242 				close(openfd);
1243 			} else {
1244 				dup2(openfd, redir->fd);
1245 				if (redir->dup == -1)
1246 					close (openfd);
1247 			}
1248 		}
1249 	}
1250 	return 0;
1251 }
1252 
1253 static void restore_redirects(int squirrel[])
1254 {
1255 	int i, fd;
1256 	for (i=0; i<3; i++) {
1257 		fd = squirrel[i];
1258 		if (fd != -1) {
1259 			/* No error checking.  I sure wouldn't know what
1260 			 * to do with an error if I found one! */
1261 			dup2(fd, i);
1262 			close(fd);
1263 		}
1264 	}
1265 }
1266 
1267 /* never returns */
1268 /* XXX no exit() here.  If you don't exec, use _exit instead.
1269  * The at_exit handlers apparently confuse the calling process,
1270  * in particular stdin handling.  Not sure why? */
1271 static void pseudo_exec(struct child_prog *child)
1272 {
1273 	int i, rcode;
1274 	char *p;
1275 	struct built_in_command *x;
1276 	if (child->argv) {
1277 		for (i=0; is_assignment(child->argv[i]); i++) {
1278 			debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
1279 			p = insert_var_value(child->argv[i]);
1280 			putenv(strdup(p));
1281 			if (p != child->argv[i]) free(p);
1282 		}
1283 		child->argv+=i;  /* XXX this hack isn't so horrible, since we are about
1284 					to exit, and therefore don't need to keep data
1285 					structures consistent for free() use. */
1286 		/* If a variable is assigned in a forest, and nobody listens,
1287 		 * was it ever really set?
1288 		 */
1289 		if (child->argv[0] == NULL) {
1290 			_exit(EXIT_SUCCESS);
1291 		}
1292 
1293 		/*
1294 		 * Check if the command matches any of the builtins.
1295 		 * Depending on context, this might be redundant.  But it's
1296 		 * easier to waste a few CPU cycles than it is to figure out
1297 		 * if this is one of those cases.
1298 		 */
1299 		for (x = bltins; x->cmd; x++) {
1300 			if (strcmp(child->argv[0], x->cmd) == 0 ) {
1301 				debug_printf("builtin exec %s\n", child->argv[0]);
1302 				rcode = x->function(child);
1303 				fflush(stdout);
1304 				_exit(rcode);
1305 			}
1306 		}
1307 
1308 		/* Check if the command matches any busybox internal commands
1309 		 * ("applets") here.
1310 		 * FIXME: This feature is not 100% safe, since
1311 		 * BusyBox is not fully reentrant, so we have no guarantee the things
1312 		 * from the .bss are still zeroed, or that things from .data are still
1313 		 * at their defaults.  We could exec ourself from /proc/self/exe, but I
1314 		 * really dislike relying on /proc for things.  We could exec ourself
1315 		 * from global_argv[0], but if we are in a chroot, we may not be able
1316 		 * to find ourself... */
1317 #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1318 		{
1319 			int argc_l;
1320 			char** argv_l=child->argv;
1321 			char *name = child->argv[0];
1322 
1323 #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
1324 			/* Following discussions from November 2000 on the busybox mailing
1325 			 * list, the default configuration, (without
1326 			 * get_last_path_component()) lets the user force use of an
1327 			 * external command by specifying the full (with slashes) filename.
1328 			 * If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN then applets
1329 			 * _aways_ override external commands, so if you want to run
1330 			 * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the
1331 			 * filesystem and is _not_ busybox.  Some systems may want this,
1332 			 * most do not.  */
1333 			name = get_last_path_component(name);
1334 #endif
1335 			/* Count argc for use in a second... */
1336 			for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
1337 			optind = 1;
1338 			debug_printf("running applet %s\n", name);
1339 			run_applet_by_name(name, argc_l, child->argv);
1340 		}
1341 #endif
1342 		debug_printf("exec of %s\n",child->argv[0]);
1343 		execvp(child->argv[0],child->argv);
1344 		perror_msg("couldn't exec: %s",child->argv[0]);
1345 		_exit(1);
1346 	} else if (child->group) {
1347 		debug_printf("runtime nesting to group\n");
1348 		interactive=0;    /* crucial!!!! */
1349 		rcode = run_list_real(child->group);
1350 		/* OK to leak memory by not calling free_pipe_list,
1351 		 * since this process is about to exit */
1352 		_exit(rcode);
1353 	} else {
1354 		/* Can happen.  See what bash does with ">foo" by itself. */
1355 		debug_printf("trying to pseudo_exec null command\n");
1356 		_exit(EXIT_SUCCESS);
1357 	}
1358 }
1359 
1360 static void insert_bg_job(struct pipe *pi)
1361 {
1362 	struct pipe *thejob;
1363 
1364 	/* Linear search for the ID of the job to use */
1365 	pi->jobid = 1;
1366 	for (thejob = job_list; thejob; thejob = thejob->next)
1367 		if (thejob->jobid >= pi->jobid)
1368 			pi->jobid = thejob->jobid + 1;
1369 
1370 	/* add thejob to the list of running jobs */
1371 	if (!job_list) {
1372 		thejob = job_list = xmalloc(sizeof(*thejob));
1373 	} else {
1374 		for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
1375 		thejob->next = xmalloc(sizeof(*thejob));
1376 		thejob = thejob->next;
1377 	}
1378 
1379 	/* physically copy the struct job */
1380 	memcpy(thejob, pi, sizeof(struct pipe));
1381 	thejob->next = NULL;
1382 	thejob->running_progs = thejob->num_progs;
1383 	thejob->stopped_progs = 0;
1384 	thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1385 
1386 	/*if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) */
1387 	{
1388 		char *bar=thejob->text;
1389 		char **foo=pi->progs[0].argv;
1390 		while(foo && *foo) {
1391 			bar += sprintf(bar, "%s ", *foo++);
1392 		}
1393 	}
1394 
1395 	/* we don't wait for background thejobs to return -- append it
1396 	   to the list of backgrounded thejobs and leave it alone */
1397 	printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1398 	last_bg_pid = thejob->progs[0].pid;
1399 	last_jobid = thejob->jobid;
1400 }
1401 
1402 /* remove a backgrounded job */
1403 static void remove_bg_job(struct pipe *pi)
1404 {
1405 	struct pipe *prev_pipe;
1406 
1407 	if (pi == job_list) {
1408 		job_list = pi->next;
1409 	} else {
1410 		prev_pipe = job_list;
1411 		while (prev_pipe->next != pi)
1412 			prev_pipe = prev_pipe->next;
1413 		prev_pipe->next = pi->next;
1414 	}
1415 	if (job_list)
1416 		last_jobid = job_list->jobid;
1417 	else
1418 		last_jobid = 0;
1419 
1420 	pi->stopped_progs = 0;
1421 	free_pipe(pi, 0);
1422 	free(pi);
1423 }
1424 
1425 /* Checks to see if any processes have exited -- if they
1426    have, figure out why and see if a job has completed */
1427 static int checkjobs(struct pipe* fg_pipe)
1428 {
1429 	int attributes;
1430 	int status;
1431 	int prognum = 0;
1432 	struct pipe *pi;
1433 	pid_t childpid;
1434 
1435 	attributes = WUNTRACED;
1436 	if (fg_pipe==NULL) {
1437 		attributes |= WNOHANG;
1438 	}
1439 
1440 	while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1441 		if (fg_pipe) {
1442 			int i, rcode = 0;
1443 			for (i=0; i < fg_pipe->num_progs; i++) {
1444 				if (fg_pipe->progs[i].pid == childpid) {
1445 					if (i==fg_pipe->num_progs-1)
1446 						rcode=WEXITSTATUS(status);
1447 					(fg_pipe->num_progs)--;
1448 					return(rcode);
1449 				}
1450 			}
1451 		}
1452 
1453 		for (pi = job_list; pi; pi = pi->next) {
1454 			prognum = 0;
1455 			while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1456 				prognum++;
1457 			}
1458 			if (prognum < pi->num_progs)
1459 				break;
1460 		}
1461 
1462 		if(pi==NULL) {
1463 			debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
1464 			continue;
1465 		}
1466 
1467 		if (WIFEXITED(status) || WIFSIGNALED(status)) {
1468 			/* child exited */
1469 			pi->running_progs--;
1470 			pi->progs[prognum].pid = 0;
1471 
1472 			if (!pi->running_progs) {
1473 				printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
1474 				remove_bg_job(pi);
1475 			}
1476 		} else {
1477 			/* child stopped */
1478 			pi->stopped_progs++;
1479 			pi->progs[prognum].is_stopped = 1;
1480 
1481 #if 0
1482 			/* Printing this stuff is a pain, since it tends to
1483 			 * overwrite the prompt an inconveinient moments.  So
1484 			 * don't do that.  */
1485 			if (pi->stopped_progs == pi->num_progs) {
1486 				printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
1487 			}
1488 #endif
1489 		}
1490 	}
1491 
1492 	if (childpid == -1 && errno != ECHILD)
1493 		perror_msg("waitpid");
1494 
1495 	/* move the shell to the foreground */
1496 	/*if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) */
1497 	/*	perror_msg("tcsetpgrp-2"); */
1498 	return -1;
1499 }
1500 
1501 /* Figure out our controlling tty, checking in order stderr,
1502  * stdin, and stdout.  If check_pgrp is set, also check that
1503  * we belong to the foreground process group associated with
1504  * that tty.  The value of shell_terminal is needed in order to call
1505  * tcsetpgrp(shell_terminal, ...); */
1506 void controlling_tty(int check_pgrp)
1507 {
1508 	pid_t curpgrp;
1509 
1510 	if ((curpgrp = tcgetpgrp(shell_terminal = 2)) < 0
1511 			&& (curpgrp = tcgetpgrp(shell_terminal = 0)) < 0
1512 			&& (curpgrp = tcgetpgrp(shell_terminal = 1)) < 0)
1513 		goto shell_terminal_error;
1514 
1515 	if (check_pgrp && curpgrp != getpgid(0))
1516 		goto shell_terminal_error;
1517 
1518 	return;
1519 
1520 shell_terminal_error:
1521 		shell_terminal = -1;
1522 		return;
1523 }
1524 #endif
1525 
1526 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1527  * to finish.  See checkjobs().
1528  *
1529  * return code is normally -1, when the caller has to wait for children
1530  * to finish to determine the exit status of the pipe.  If the pipe
1531  * is a simple builtin command, however, the action is done by the
1532  * time run_pipe_real returns, and the exit code is provided as the
1533  * return value.
1534  *
1535  * The input of the pipe is always stdin, the output is always
1536  * stdout.  The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1537  * because it tries to avoid running the command substitution in
1538  * subshell, when that is in fact necessary.  The subshell process
1539  * now has its stdout directed to the input of the appropriate pipe,
1540  * so this routine is noticeably simpler.
1541  */
1542 static int run_pipe_real(struct pipe *pi)
1543 {
1544 	int i;
1545 #ifndef __U_BOOT__
1546 	int nextin, nextout;
1547 	int pipefds[2];				/* pipefds[0] is for reading */
1548 	struct child_prog *child;
1549 	struct built_in_command *x;
1550 	char *p;
1551 # if __GNUC__
1552 	/* Avoid longjmp clobbering */
1553 	(void) &i;
1554 	(void) &nextin;
1555 	(void) &nextout;
1556 	(void) &child;
1557 # endif
1558 #else
1559 	int nextin;
1560 	int flag = do_repeat ? CMD_FLAG_REPEAT : 0;
1561 	struct child_prog *child;
1562 	cmd_tbl_t *cmdtp;
1563 	char *p;
1564 # if __GNUC__
1565 	/* Avoid longjmp clobbering */
1566 	(void) &i;
1567 	(void) &nextin;
1568 	(void) &child;
1569 # endif
1570 #endif	/* __U_BOOT__ */
1571 
1572 	nextin = 0;
1573 #ifndef __U_BOOT__
1574 	pi->pgrp = -1;
1575 #endif
1576 
1577 	/* Check if this is a simple builtin (not part of a pipe).
1578 	 * Builtins within pipes have to fork anyway, and are handled in
1579 	 * pseudo_exec.  "echo foo | read bar" doesn't work on bash, either.
1580 	 */
1581 	if (pi->num_progs == 1) child = & (pi->progs[0]);
1582 #ifndef __U_BOOT__
1583 	if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1584 		int squirrel[] = {-1, -1, -1};
1585 		int rcode;
1586 		debug_printf("non-subshell grouping\n");
1587 		setup_redirects(child, squirrel);
1588 		/* XXX could we merge code with following builtin case,
1589 		 * by creating a pseudo builtin that calls run_list_real? */
1590 		rcode = run_list_real(child->group);
1591 		restore_redirects(squirrel);
1592 #else
1593 		if (pi->num_progs == 1 && child->group) {
1594 		int rcode;
1595 		debug_printf("non-subshell grouping\n");
1596 		rcode = run_list_real(child->group);
1597 #endif
1598 		return rcode;
1599 	} else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1600 		for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
1601 		if (i!=0 && child->argv[i]==NULL) {
1602 			/* assignments, but no command: set the local environment */
1603 			for (i=0; child->argv[i]!=NULL; i++) {
1604 
1605 				/* Ok, this case is tricky.  We have to decide if this is a
1606 				 * local variable, or an already exported variable.  If it is
1607 				 * already exported, we have to export the new value.  If it is
1608 				 * not exported, we need only set this as a local variable.
1609 				 * This junk is all to decide whether or not to export this
1610 				 * variable. */
1611 				int export_me=0;
1612 				char *name, *value;
1613 				name = xstrdup(child->argv[i]);
1614 				debug_printf("Local environment set: %s\n", name);
1615 				value = strchr(name, '=');
1616 				if (value)
1617 					*value=0;
1618 #ifndef __U_BOOT__
1619 				if ( get_local_var(name)) {
1620 					export_me=1;
1621 				}
1622 #endif
1623 				free(name);
1624 				p = insert_var_value(child->argv[i]);
1625 				set_local_var(p, export_me);
1626 				if (p != child->argv[i]) free(p);
1627 			}
1628 			return EXIT_SUCCESS;   /* don't worry about errors in set_local_var() yet */
1629 		}
1630 		for (i = 0; is_assignment(child->argv[i]); i++) {
1631 			p = insert_var_value(child->argv[i]);
1632 #ifndef __U_BOOT__
1633 			putenv(strdup(p));
1634 #else
1635 			set_local_var(p, 0);
1636 #endif
1637 			if (p != child->argv[i]) {
1638 				child->sp--;
1639 				free(p);
1640 			}
1641 		}
1642 		if (child->sp) {
1643 			char * str = NULL;
1644 
1645 			str = make_string((child->argv + i));
1646 			parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1647 			free(str);
1648 			return last_return_code;
1649 		}
1650 #ifndef __U_BOOT__
1651 		for (x = bltins; x->cmd; x++) {
1652 			if (strcmp(child->argv[i], x->cmd) == 0 ) {
1653 				int squirrel[] = {-1, -1, -1};
1654 				int rcode;
1655 				if (x->function == builtin_exec && child->argv[i+1]==NULL) {
1656 					debug_printf("magic exec\n");
1657 					setup_redirects(child,NULL);
1658 					return EXIT_SUCCESS;
1659 				}
1660 				debug_printf("builtin inline %s\n", child->argv[0]);
1661 				/* XXX setup_redirects acts on file descriptors, not FILEs.
1662 				 * This is perfect for work that comes after exec().
1663 				 * Is it really safe for inline use?  Experimentally,
1664 				 * things seem to work with glibc. */
1665 				setup_redirects(child, squirrel);
1666 #else
1667 			/* check ";", because ,example , argv consist from
1668 			 * "help;flinfo" must not execute
1669 			 */
1670 			if (strchr(child->argv[i], ';')) {
1671 				printf ("Unknown command '%s' - try 'help' or use 'run' command\n",
1672 					child->argv[i]);
1673 				return -1;
1674 			}
1675 			/* Look up command in command table */
1676 
1677 
1678 			if ((cmdtp = find_cmd(child->argv[i])) == NULL) {
1679 				printf ("Unknown command '%s' - try 'help'\n", child->argv[i]);
1680 				return -1;	/* give up after bad command */
1681 			} else {
1682 				int rcode;
1683 #if defined(CONFIG_CMD_BOOTD)
1684 	    extern int do_bootd (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]);
1685 
1686 				/* avoid "bootd" recursion */
1687 				if (cmdtp->cmd == do_bootd) {
1688 					if (flag & CMD_FLAG_BOOTD) {
1689 						printf ("'bootd' recursion detected\n");
1690 						return -1;
1691 					}
1692 				else
1693 					flag |= CMD_FLAG_BOOTD;
1694 				}
1695 #endif
1696 				/* found - check max args */
1697 				if ((child->argc - i) > cmdtp->maxargs) {
1698 					cmd_usage(cmdtp);
1699 					return -1;
1700 				}
1701 #endif
1702 				child->argv+=i;  /* XXX horrible hack */
1703 #ifndef __U_BOOT__
1704 				rcode = x->function(child);
1705 #else
1706 				/* OK - call function to do the command */
1707 
1708 				rcode = (cmdtp->cmd)
1709 (cmdtp, flag,child->argc-i,&child->argv[i]);
1710 				if ( !cmdtp->repeatable )
1711 					flag_repeat = 0;
1712 
1713 
1714 #endif
1715 				child->argv-=i;  /* XXX restore hack so free() can work right */
1716 #ifndef __U_BOOT__
1717 
1718 				restore_redirects(squirrel);
1719 #endif
1720 
1721 				return rcode;
1722 			}
1723 		}
1724 #ifndef __U_BOOT__
1725 	}
1726 
1727 	for (i = 0; i < pi->num_progs; i++) {
1728 		child = & (pi->progs[i]);
1729 
1730 		/* pipes are inserted between pairs of commands */
1731 		if ((i + 1) < pi->num_progs) {
1732 			if (pipe(pipefds)<0) perror_msg_and_die("pipe");
1733 			nextout = pipefds[1];
1734 		} else {
1735 			nextout=1;
1736 			pipefds[0] = -1;
1737 		}
1738 
1739 		/* XXX test for failed fork()? */
1740 		if (!(child->pid = fork())) {
1741 			/* Set the handling for job control signals back to the default.  */
1742 			signal(SIGINT, SIG_DFL);
1743 			signal(SIGQUIT, SIG_DFL);
1744 			signal(SIGTERM, SIG_DFL);
1745 			signal(SIGTSTP, SIG_DFL);
1746 			signal(SIGTTIN, SIG_DFL);
1747 			signal(SIGTTOU, SIG_DFL);
1748 			signal(SIGCHLD, SIG_DFL);
1749 
1750 			close_all();
1751 
1752 			if (nextin != 0) {
1753 				dup2(nextin, 0);
1754 				close(nextin);
1755 			}
1756 			if (nextout != 1) {
1757 				dup2(nextout, 1);
1758 				close(nextout);
1759 			}
1760 			if (pipefds[0]!=-1) {
1761 				close(pipefds[0]);  /* opposite end of our output pipe */
1762 			}
1763 
1764 			/* Like bash, explicit redirects override pipes,
1765 			 * and the pipe fd is available for dup'ing. */
1766 			setup_redirects(child,NULL);
1767 
1768 			if (interactive && pi->followup!=PIPE_BG) {
1769 				/* If we (the child) win the race, put ourselves in the process
1770 				 * group whose leader is the first process in this pipe. */
1771 				if (pi->pgrp < 0) {
1772 					pi->pgrp = getpid();
1773 				}
1774 				if (setpgid(0, pi->pgrp) == 0) {
1775 					tcsetpgrp(2, pi->pgrp);
1776 				}
1777 			}
1778 
1779 			pseudo_exec(child);
1780 		}
1781 
1782 
1783 		/* put our child in the process group whose leader is the
1784 		   first process in this pipe */
1785 		if (pi->pgrp < 0) {
1786 			pi->pgrp = child->pid;
1787 		}
1788 		/* Don't check for errors.  The child may be dead already,
1789 		 * in which case setpgid returns error code EACCES. */
1790 		setpgid(child->pid, pi->pgrp);
1791 
1792 		if (nextin != 0)
1793 			close(nextin);
1794 		if (nextout != 1)
1795 			close(nextout);
1796 
1797 		/* If there isn't another process, nextin is garbage
1798 		   but it doesn't matter */
1799 		nextin = pipefds[0];
1800 	}
1801 #endif
1802 	return -1;
1803 }
1804 
1805 static int run_list_real(struct pipe *pi)
1806 {
1807 	char *save_name = NULL;
1808 	char **list = NULL;
1809 	char **save_list = NULL;
1810 	struct pipe *rpipe;
1811 	int flag_rep = 0;
1812 #ifndef __U_BOOT__
1813 	int save_num_progs;
1814 #endif
1815 	int rcode=0, flag_skip=1;
1816 	int flag_restore = 0;
1817 	int if_code=0, next_if_code=0;  /* need double-buffer to handle elif */
1818 	reserved_style rmode, skip_more_in_this_rmode=RES_XXXX;
1819 	/* check syntax for "for" */
1820 	for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1821 		if ((rpipe->r_mode == RES_IN ||
1822 		    rpipe->r_mode == RES_FOR) &&
1823 		    (rpipe->next == NULL)) {
1824 				syntax();
1825 #ifdef __U_BOOT__
1826 				flag_repeat = 0;
1827 #endif
1828 				return 1;
1829 		}
1830 		if ((rpipe->r_mode == RES_IN &&
1831 			(rpipe->next->r_mode == RES_IN &&
1832 			rpipe->next->progs->argv != NULL))||
1833 			(rpipe->r_mode == RES_FOR &&
1834 			rpipe->next->r_mode != RES_IN)) {
1835 				syntax();
1836 #ifdef __U_BOOT__
1837 				flag_repeat = 0;
1838 #endif
1839 				return 1;
1840 		}
1841 	}
1842 	for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1843 		if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
1844 			pi->r_mode == RES_FOR) {
1845 #ifdef __U_BOOT__
1846 				/* check Ctrl-C */
1847 				ctrlc();
1848 				if ((had_ctrlc())) {
1849 					return 1;
1850 				}
1851 #endif
1852 				flag_restore = 0;
1853 				if (!rpipe) {
1854 					flag_rep = 0;
1855 					rpipe = pi;
1856 				}
1857 		}
1858 		rmode = pi->r_mode;
1859 		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);
1860 		if (rmode == skip_more_in_this_rmode && flag_skip) {
1861 			if (pi->followup == PIPE_SEQ) flag_skip=0;
1862 			continue;
1863 		}
1864 		flag_skip = 1;
1865 		skip_more_in_this_rmode = RES_XXXX;
1866 		if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
1867 		if (rmode == RES_THEN &&  if_code) continue;
1868 		if (rmode == RES_ELSE && !if_code) continue;
1869 		if (rmode == RES_ELIF && !if_code) break;
1870 		if (rmode == RES_FOR && pi->num_progs) {
1871 			if (!list) {
1872 				/* if no variable values after "in" we skip "for" */
1873 				if (!pi->next->progs->argv) continue;
1874 				/* create list of variable values */
1875 				list = make_list_in(pi->next->progs->argv,
1876 					pi->progs->argv[0]);
1877 				save_list = list;
1878 				save_name = pi->progs->argv[0];
1879 				pi->progs->argv[0] = NULL;
1880 				flag_rep = 1;
1881 			}
1882 			if (!(*list)) {
1883 				free(pi->progs->argv[0]);
1884 				free(save_list);
1885 				list = NULL;
1886 				flag_rep = 0;
1887 				pi->progs->argv[0] = save_name;
1888 #ifndef __U_BOOT__
1889 				pi->progs->glob_result.gl_pathv[0] =
1890 					pi->progs->argv[0];
1891 #endif
1892 				continue;
1893 			} else {
1894 				/* insert new value from list for variable */
1895 				if (pi->progs->argv[0])
1896 					free(pi->progs->argv[0]);
1897 				pi->progs->argv[0] = *list++;
1898 #ifndef __U_BOOT__
1899 				pi->progs->glob_result.gl_pathv[0] =
1900 					pi->progs->argv[0];
1901 #endif
1902 			}
1903 		}
1904 		if (rmode == RES_IN) continue;
1905 		if (rmode == RES_DO) {
1906 			if (!flag_rep) continue;
1907 		}
1908 		if ((rmode == RES_DONE)) {
1909 			if (flag_rep) {
1910 				flag_restore = 1;
1911 			} else {
1912 				rpipe = NULL;
1913 			}
1914 		}
1915 		if (pi->num_progs == 0) continue;
1916 #ifndef __U_BOOT__
1917 		save_num_progs = pi->num_progs; /* save number of programs */
1918 #endif
1919 		rcode = run_pipe_real(pi);
1920 		debug_printf("run_pipe_real returned %d\n",rcode);
1921 #ifndef __U_BOOT__
1922 		if (rcode!=-1) {
1923 			/* We only ran a builtin: rcode was set by the return value
1924 			 * of run_pipe_real(), and we don't need to wait for anything. */
1925 		} else if (pi->followup==PIPE_BG) {
1926 			/* XXX check bash's behavior with nontrivial pipes */
1927 			/* XXX compute jobid */
1928 			/* XXX what does bash do with attempts to background builtins? */
1929 			insert_bg_job(pi);
1930 			rcode = EXIT_SUCCESS;
1931 		} else {
1932 			if (interactive) {
1933 				/* move the new process group into the foreground */
1934 				if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1935 					perror_msg("tcsetpgrp-3");
1936 				rcode = checkjobs(pi);
1937 				/* move the shell to the foreground */
1938 				if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1939 					perror_msg("tcsetpgrp-4");
1940 			} else {
1941 				rcode = checkjobs(pi);
1942 			}
1943 			debug_printf("checkjobs returned %d\n",rcode);
1944 		}
1945 		last_return_code=rcode;
1946 #else
1947 		if (rcode < -1) {
1948 			last_return_code = -rcode - 2;
1949 			return -2;	/* exit */
1950 		}
1951 		last_return_code=(rcode == 0) ? 0 : 1;
1952 #endif
1953 #ifndef __U_BOOT__
1954 		pi->num_progs = save_num_progs; /* restore number of programs */
1955 #endif
1956 		if ( rmode == RES_IF || rmode == RES_ELIF )
1957 			next_if_code=rcode;  /* can be overwritten a number of times */
1958 		if (rmode == RES_WHILE)
1959 			flag_rep = !last_return_code;
1960 		if (rmode == RES_UNTIL)
1961 			flag_rep = last_return_code;
1962 		if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
1963 		     (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
1964 			skip_more_in_this_rmode=rmode;
1965 #ifndef __U_BOOT__
1966 		checkjobs(NULL);
1967 #endif
1968 	}
1969 	return rcode;
1970 }
1971 
1972 /* broken, of course, but OK for testing */
1973 static char *indenter(int i)
1974 {
1975 	static char blanks[]="                                    ";
1976 	return &blanks[sizeof(blanks)-i-1];
1977 }
1978 
1979 /* return code is the exit status of the pipe */
1980 static int free_pipe(struct pipe *pi, int indent)
1981 {
1982 	char **p;
1983 	struct child_prog *child;
1984 #ifndef __U_BOOT__
1985 	struct redir_struct *r, *rnext;
1986 #endif
1987 	int a, i, ret_code=0;
1988 	char *ind = indenter(indent);
1989 
1990 #ifndef __U_BOOT__
1991 	if (pi->stopped_progs > 0)
1992 		return ret_code;
1993 	final_printf("%s run pipe: (pid %d)\n",ind,getpid());
1994 #endif
1995 	for (i=0; i<pi->num_progs; i++) {
1996 		child = &pi->progs[i];
1997 		final_printf("%s  command %d:\n",ind,i);
1998 		if (child->argv) {
1999 			for (a=0,p=child->argv; *p; a++,p++) {
2000 				final_printf("%s   argv[%d] = %s\n",ind,a,*p);
2001 			}
2002 #ifndef __U_BOOT__
2003 			globfree(&child->glob_result);
2004 #else
2005 			for (a = 0; a < child->argc; a++) {
2006 				free(child->argv[a]);
2007 			}
2008 					free(child->argv);
2009 			child->argc = 0;
2010 #endif
2011 			child->argv=NULL;
2012 		} else if (child->group) {
2013 #ifndef __U_BOOT__
2014 			final_printf("%s   begin group (subshell:%d)\n",ind, child->subshell);
2015 #endif
2016 			ret_code = free_pipe_list(child->group,indent+3);
2017 			final_printf("%s   end group\n",ind);
2018 		} else {
2019 			final_printf("%s   (nil)\n",ind);
2020 		}
2021 #ifndef __U_BOOT__
2022 		for (r=child->redirects; r; r=rnext) {
2023 			final_printf("%s   redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
2024 			if (r->dup == -1) {
2025 				/* guard against the case >$FOO, where foo is unset or blank */
2026 				if (r->word.gl_pathv) {
2027 					final_printf(" %s\n", *r->word.gl_pathv);
2028 					globfree(&r->word);
2029 				}
2030 			} else {
2031 				final_printf("&%d\n", r->dup);
2032 			}
2033 			rnext=r->next;
2034 			free(r);
2035 		}
2036 		child->redirects=NULL;
2037 #endif
2038 	}
2039 	free(pi->progs);   /* children are an array, they get freed all at once */
2040 	pi->progs=NULL;
2041 	return ret_code;
2042 }
2043 
2044 static int free_pipe_list(struct pipe *head, int indent)
2045 {
2046 	int rcode=0;   /* if list has no members */
2047 	struct pipe *pi, *next;
2048 	char *ind = indenter(indent);
2049 	for (pi=head; pi; pi=next) {
2050 		final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
2051 		rcode = free_pipe(pi, indent);
2052 		final_printf("%s pipe followup code %d\n", ind, pi->followup);
2053 		next=pi->next;
2054 		pi->next=NULL;
2055 		free(pi);
2056 	}
2057 	return rcode;
2058 }
2059 
2060 /* Select which version we will use */
2061 static int run_list(struct pipe *pi)
2062 {
2063 	int rcode=0;
2064 #ifndef __U_BOOT__
2065 	if (fake_mode==0) {
2066 #endif
2067 		rcode = run_list_real(pi);
2068 #ifndef __U_BOOT__
2069 	}
2070 #endif
2071 	/* free_pipe_list has the side effect of clearing memory
2072 	 * In the long run that function can be merged with run_list_real,
2073 	 * but doing that now would hobble the debugging effort. */
2074 	free_pipe_list(pi,0);
2075 	return rcode;
2076 }
2077 
2078 /* The API for glob is arguably broken.  This routine pushes a non-matching
2079  * string into the output structure, removing non-backslashed backslashes.
2080  * If someone can prove me wrong, by performing this function within the
2081  * original glob(3) api, feel free to rewrite this routine into oblivion.
2082  * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
2083  * XXX broken if the last character is '\\', check that before calling.
2084  */
2085 #ifndef __U_BOOT__
2086 static int globhack(const char *src, int flags, glob_t *pglob)
2087 {
2088 	int cnt=0, pathc;
2089 	const char *s;
2090 	char *dest;
2091 	for (cnt=1, s=src; s && *s; s++) {
2092 		if (*s == '\\') s++;
2093 		cnt++;
2094 	}
2095 	dest = malloc(cnt);
2096 	if (!dest) return GLOB_NOSPACE;
2097 	if (!(flags & GLOB_APPEND)) {
2098 		pglob->gl_pathv=NULL;
2099 		pglob->gl_pathc=0;
2100 		pglob->gl_offs=0;
2101 		pglob->gl_offs=0;
2102 	}
2103 	pathc = ++pglob->gl_pathc;
2104 	pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
2105 	if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
2106 	pglob->gl_pathv[pathc-1]=dest;
2107 	pglob->gl_pathv[pathc]=NULL;
2108 	for (s=src; s && *s; s++, dest++) {
2109 		if (*s == '\\') s++;
2110 		*dest = *s;
2111 	}
2112 	*dest='\0';
2113 	return 0;
2114 }
2115 
2116 /* XXX broken if the last character is '\\', check that before calling */
2117 static int glob_needed(const char *s)
2118 {
2119 	for (; *s; s++) {
2120 		if (*s == '\\') s++;
2121 		if (strchr("*[?",*s)) return 1;
2122 	}
2123 	return 0;
2124 }
2125 
2126 #if 0
2127 static void globprint(glob_t *pglob)
2128 {
2129 	int i;
2130 	debug_printf("glob_t at %p:\n", pglob);
2131 	debug_printf("  gl_pathc=%d  gl_pathv=%p  gl_offs=%d  gl_flags=%d\n",
2132 		pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
2133 	for (i=0; i<pglob->gl_pathc; i++)
2134 		debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
2135 			pglob->gl_pathv[i], pglob->gl_pathv[i]);
2136 }
2137 #endif
2138 
2139 static int xglob(o_string *dest, int flags, glob_t *pglob)
2140 {
2141 	int gr;
2142 
2143 	/* short-circuit for null word */
2144 	/* we can code this better when the debug_printf's are gone */
2145 	if (dest->length == 0) {
2146 		if (dest->nonnull) {
2147 			/* bash man page calls this an "explicit" null */
2148 			gr = globhack(dest->data, flags, pglob);
2149 			debug_printf("globhack returned %d\n",gr);
2150 		} else {
2151 			return 0;
2152 		}
2153 	} else if (glob_needed(dest->data)) {
2154 		gr = glob(dest->data, flags, NULL, pglob);
2155 		debug_printf("glob returned %d\n",gr);
2156 		if (gr == GLOB_NOMATCH) {
2157 			/* quote removal, or more accurately, backslash removal */
2158 			gr = globhack(dest->data, flags, pglob);
2159 			debug_printf("globhack returned %d\n",gr);
2160 		}
2161 	} else {
2162 		gr = globhack(dest->data, flags, pglob);
2163 		debug_printf("globhack returned %d\n",gr);
2164 	}
2165 	if (gr == GLOB_NOSPACE)
2166 		error_msg_and_die("out of memory during glob");
2167 	if (gr != 0) { /* GLOB_ABORTED ? */
2168 		error_msg("glob(3) error %d",gr);
2169 	}
2170 	/* globprint(glob_target); */
2171 	return gr;
2172 }
2173 #endif
2174 
2175 #ifdef __U_BOOT__
2176 static char *get_dollar_var(char ch);
2177 #endif
2178 
2179 /* This is used to get/check local shell variables */
2180 static char *get_local_var(const char *s)
2181 {
2182 	struct variables *cur;
2183 
2184 	if (!s)
2185 		return NULL;
2186 
2187 #ifdef __U_BOOT__
2188 	if (*s == '$')
2189 		return get_dollar_var(s[1]);
2190 #endif
2191 
2192 	for (cur = top_vars; cur; cur=cur->next)
2193 		if(strcmp(cur->name, s)==0)
2194 			return cur->value;
2195 	return NULL;
2196 }
2197 
2198 /* This is used to set local shell variables
2199    flg_export==0 if only local (not exporting) variable
2200    flg_export==1 if "new" exporting environ
2201    flg_export>1  if current startup environ (not call putenv()) */
2202 int set_local_var(const char *s, int flg_export)
2203 {
2204 	char *name, *value;
2205 	int result=0;
2206 	struct variables *cur;
2207 
2208 #ifdef __U_BOOT__
2209 	/* might be possible! */
2210 	if (!isalpha(*s))
2211 		return -1;
2212 #endif
2213 
2214 	name=strdup(s);
2215 
2216 #ifdef __U_BOOT__
2217 	if (getenv(name) != NULL) {
2218 		printf ("ERROR: "
2219 				"There is a global environment variable with the same name.\n");
2220 		free(name);
2221 		return -1;
2222 	}
2223 #endif
2224 	/* Assume when we enter this function that we are already in
2225 	 * NAME=VALUE format.  So the first order of business is to
2226 	 * split 's' on the '=' into 'name' and 'value' */
2227 	value = strchr(name, '=');
2228 	if (value==0 && ++value==0) {
2229 		free(name);
2230 		return -1;
2231 	}
2232 	*value++ = 0;
2233 
2234 	for(cur = top_vars; cur; cur = cur->next) {
2235 		if(strcmp(cur->name, name)==0)
2236 			break;
2237 	}
2238 
2239 	if(cur) {
2240 		if(strcmp(cur->value, value)==0) {
2241 			if(flg_export>0 && cur->flg_export==0)
2242 				cur->flg_export=flg_export;
2243 			else
2244 				result++;
2245 		} else {
2246 			if(cur->flg_read_only) {
2247 				error_msg("%s: readonly variable", name);
2248 				result = -1;
2249 			} else {
2250 				if(flg_export>0 || cur->flg_export>1)
2251 					cur->flg_export=1;
2252 				free(cur->value);
2253 
2254 				cur->value = strdup(value);
2255 			}
2256 		}
2257 	} else {
2258 		cur = malloc(sizeof(struct variables));
2259 		if(!cur) {
2260 			result = -1;
2261 		} else {
2262 			cur->name = strdup(name);
2263 			if(cur->name == 0) {
2264 				free(cur);
2265 				result = -1;
2266 			} else {
2267 				struct variables *bottom = top_vars;
2268 				cur->value = strdup(value);
2269 				cur->next = 0;
2270 				cur->flg_export = flg_export;
2271 				cur->flg_read_only = 0;
2272 				while(bottom->next) bottom=bottom->next;
2273 				bottom->next = cur;
2274 			}
2275 		}
2276 	}
2277 
2278 #ifndef __U_BOOT__
2279 	if(result==0 && cur->flg_export==1) {
2280 		*(value-1) = '=';
2281 		result = putenv(name);
2282 	} else {
2283 #endif
2284 		free(name);
2285 #ifndef __U_BOOT__
2286 		if(result>0)            /* equivalent to previous set */
2287 			result = 0;
2288 	}
2289 #endif
2290 	return result;
2291 }
2292 
2293 void unset_local_var(const char *name)
2294 {
2295 	struct variables *cur;
2296 
2297 	if (name) {
2298 		for (cur = top_vars; cur; cur=cur->next) {
2299 			if(strcmp(cur->name, name)==0)
2300 				break;
2301 		}
2302 		if(cur!=0) {
2303 			struct variables *next = top_vars;
2304 			if(cur->flg_read_only) {
2305 				error_msg("%s: readonly variable", name);
2306 				return;
2307 			} else {
2308 #ifndef __U_BOOT__
2309 				if(cur->flg_export)
2310 					unsetenv(cur->name);
2311 #endif
2312 				free(cur->name);
2313 				free(cur->value);
2314 				while (next->next != cur)
2315 					next = next->next;
2316 				next->next = cur->next;
2317 			}
2318 			free(cur);
2319 		}
2320 	}
2321 }
2322 
2323 static int is_assignment(const char *s)
2324 {
2325 	if (s == NULL)
2326 		return 0;
2327 
2328 	if (!isalpha(*s)) return 0;
2329 	++s;
2330 	while(isalnum(*s) || *s=='_') ++s;
2331 	return *s=='=';
2332 }
2333 
2334 #ifndef __U_BOOT__
2335 /* the src parameter allows us to peek forward to a possible &n syntax
2336  * for file descriptor duplication, e.g., "2>&1".
2337  * Return code is 0 normally, 1 if a syntax error is detected in src.
2338  * Resource errors (in xmalloc) cause the process to exit */
2339 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
2340 	struct in_str *input)
2341 {
2342 	struct child_prog *child=ctx->child;
2343 	struct redir_struct *redir = child->redirects;
2344 	struct redir_struct *last_redir=NULL;
2345 
2346 	/* Create a new redir_struct and drop it onto the end of the linked list */
2347 	while(redir) {
2348 		last_redir=redir;
2349 		redir=redir->next;
2350 	}
2351 	redir = xmalloc(sizeof(struct redir_struct));
2352 	redir->next=NULL;
2353 	redir->word.gl_pathv=NULL;
2354 	if (last_redir) {
2355 		last_redir->next=redir;
2356 	} else {
2357 		child->redirects=redir;
2358 	}
2359 
2360 	redir->type=style;
2361 	redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
2362 
2363 	debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
2364 
2365 	/* Check for a '2>&1' type redirect */
2366 	redir->dup = redirect_dup_num(input);
2367 	if (redir->dup == -2) return 1;  /* syntax error */
2368 	if (redir->dup != -1) {
2369 		/* Erik had a check here that the file descriptor in question
2370 		 * is legit; I postpone that to "run time"
2371 		 * A "-" representation of "close me" shows up as a -3 here */
2372 		debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
2373 	} else {
2374 		/* We do _not_ try to open the file that src points to,
2375 		 * since we need to return and let src be expanded first.
2376 		 * Set ctx->pending_redirect, so we know what to do at the
2377 		 * end of the next parsed word.
2378 		 */
2379 		ctx->pending_redirect = redir;
2380 	}
2381 	return 0;
2382 }
2383 #endif
2384 
2385 struct pipe *new_pipe(void) {
2386 	struct pipe *pi;
2387 	pi = xmalloc(sizeof(struct pipe));
2388 	pi->num_progs = 0;
2389 	pi->progs = NULL;
2390 	pi->next = NULL;
2391 	pi->followup = 0;  /* invalid */
2392 	pi->r_mode = RES_NONE;
2393 	return pi;
2394 }
2395 
2396 static void initialize_context(struct p_context *ctx)
2397 {
2398 	ctx->pipe=NULL;
2399 #ifndef __U_BOOT__
2400 	ctx->pending_redirect=NULL;
2401 #endif
2402 	ctx->child=NULL;
2403 	ctx->list_head=new_pipe();
2404 	ctx->pipe=ctx->list_head;
2405 	ctx->w=RES_NONE;
2406 	ctx->stack=NULL;
2407 #ifdef __U_BOOT__
2408 	ctx->old_flag=0;
2409 #endif
2410 	done_command(ctx);   /* creates the memory for working child */
2411 }
2412 
2413 /* normal return is 0
2414  * if a reserved word is found, and processed, return 1
2415  * should handle if, then, elif, else, fi, for, while, until, do, done.
2416  * case, function, and select are obnoxious, save those for later.
2417  */
2418 struct reserved_combo {
2419 	char *literal;
2420 	int code;
2421 	long flag;
2422 };
2423 /* Mostly a list of accepted follow-up reserved words.
2424  * FLAG_END means we are done with the sequence, and are ready
2425  * to turn the compound list into a command.
2426  * FLAG_START means the word must start a new compound list.
2427  */
2428 static struct reserved_combo reserved_list[] = {
2429 	{ "if",    RES_IF,    FLAG_THEN | FLAG_START },
2430 	{ "then",  RES_THEN,  FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2431 	{ "elif",  RES_ELIF,  FLAG_THEN },
2432 	{ "else",  RES_ELSE,  FLAG_FI   },
2433 	{ "fi",    RES_FI,    FLAG_END  },
2434 	{ "for",   RES_FOR,   FLAG_IN   | FLAG_START },
2435 	{ "while", RES_WHILE, FLAG_DO   | FLAG_START },
2436 	{ "until", RES_UNTIL, FLAG_DO   | FLAG_START },
2437 	{ "in",    RES_IN,    FLAG_DO   },
2438 	{ "do",    RES_DO,    FLAG_DONE },
2439 	{ "done",  RES_DONE,  FLAG_END  }
2440 };
2441 #define NRES (sizeof(reserved_list)/sizeof(struct reserved_combo))
2442 
2443 int reserved_word(o_string *dest, struct p_context *ctx)
2444 {
2445 	struct reserved_combo *r;
2446 	for (r=reserved_list;
2447 		r<reserved_list+NRES; r++) {
2448 		if (strcmp(dest->data, r->literal) == 0) {
2449 			debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2450 			if (r->flag & FLAG_START) {
2451 				struct p_context *new = xmalloc(sizeof(struct p_context));
2452 				debug_printf("push stack\n");
2453 				if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2454 					syntax();
2455 					free(new);
2456 					ctx->w = RES_SNTX;
2457 					b_reset(dest);
2458 					return 1;
2459 				}
2460 				*new = *ctx;   /* physical copy */
2461 				initialize_context(ctx);
2462 				ctx->stack=new;
2463 			} else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2464 				syntax();
2465 				ctx->w = RES_SNTX;
2466 				b_reset(dest);
2467 				return 1;
2468 			}
2469 			ctx->w=r->code;
2470 			ctx->old_flag = r->flag;
2471 			if (ctx->old_flag & FLAG_END) {
2472 				struct p_context *old;
2473 				debug_printf("pop stack\n");
2474 				done_pipe(ctx,PIPE_SEQ);
2475 				old = ctx->stack;
2476 				old->child->group = ctx->list_head;
2477 #ifndef __U_BOOT__
2478 				old->child->subshell = 0;
2479 #endif
2480 				*ctx = *old;   /* physical copy */
2481 				free(old);
2482 			}
2483 			b_reset (dest);
2484 			return 1;
2485 		}
2486 	}
2487 	return 0;
2488 }
2489 
2490 /* normal return is 0.
2491  * Syntax or xglob errors return 1. */
2492 static int done_word(o_string *dest, struct p_context *ctx)
2493 {
2494 	struct child_prog *child=ctx->child;
2495 #ifndef __U_BOOT__
2496 	glob_t *glob_target;
2497 	int gr, flags = 0;
2498 #else
2499 	char *str, *s;
2500 	int argc, cnt;
2501 #endif
2502 
2503 	debug_printf("done_word: %s %p\n", dest->data, child);
2504 	if (dest->length == 0 && !dest->nonnull) {
2505 		debug_printf("  true null, ignored\n");
2506 		return 0;
2507 	}
2508 #ifndef __U_BOOT__
2509 	if (ctx->pending_redirect) {
2510 		glob_target = &ctx->pending_redirect->word;
2511 	} else {
2512 #endif
2513 		if (child->group) {
2514 			syntax();
2515 			return 1;  /* syntax error, groups and arglists don't mix */
2516 		}
2517 		if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2518 			debug_printf("checking %s for reserved-ness\n",dest->data);
2519 			if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2520 		}
2521 #ifndef __U_BOOT__
2522 		glob_target = &child->glob_result;
2523 		if (child->argv) flags |= GLOB_APPEND;
2524 #else
2525 		for (cnt = 1, s = dest->data; s && *s; s++) {
2526 			if (*s == '\\') s++;
2527 			cnt++;
2528 		}
2529 		str = malloc(cnt);
2530 		if (!str) return 1;
2531 		if ( child->argv == NULL) {
2532 			child->argc=0;
2533 		}
2534 		argc = ++child->argc;
2535 		child->argv = realloc(child->argv, (argc+1)*sizeof(*child->argv));
2536 		if (child->argv == NULL) return 1;
2537 		child->argv[argc-1]=str;
2538 		child->argv[argc]=NULL;
2539 		for (s = dest->data; s && *s; s++,str++) {
2540 			if (*s == '\\') s++;
2541 			*str = *s;
2542 		}
2543 		*str = '\0';
2544 #endif
2545 #ifndef __U_BOOT__
2546 	}
2547 	gr = xglob(dest, flags, glob_target);
2548 	if (gr != 0) return 1;
2549 #endif
2550 
2551 	b_reset(dest);
2552 #ifndef __U_BOOT__
2553 	if (ctx->pending_redirect) {
2554 		ctx->pending_redirect=NULL;
2555 		if (glob_target->gl_pathc != 1) {
2556 			error_msg("ambiguous redirect");
2557 			return 1;
2558 		}
2559 	} else {
2560 		child->argv = glob_target->gl_pathv;
2561 	}
2562 #endif
2563 	if (ctx->w == RES_FOR) {
2564 		done_word(dest,ctx);
2565 		done_pipe(ctx,PIPE_SEQ);
2566 	}
2567 	return 0;
2568 }
2569 
2570 /* The only possible error here is out of memory, in which case
2571  * xmalloc exits. */
2572 static int done_command(struct p_context *ctx)
2573 {
2574 	/* The child is really already in the pipe structure, so
2575 	 * advance the pipe counter and make a new, null child.
2576 	 * Only real trickiness here is that the uncommitted
2577 	 * child structure, to which ctx->child points, is not
2578 	 * counted in pi->num_progs. */
2579 	struct pipe *pi=ctx->pipe;
2580 	struct child_prog *prog=ctx->child;
2581 
2582 	if (prog && prog->group == NULL
2583 		 && prog->argv == NULL
2584 #ifndef __U_BOOT__
2585 		 && prog->redirects == NULL) {
2586 #else
2587 										) {
2588 #endif
2589 		debug_printf("done_command: skipping null command\n");
2590 		return 0;
2591 	} else if (prog) {
2592 		pi->num_progs++;
2593 		debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2594 	} else {
2595 		debug_printf("done_command: initializing\n");
2596 	}
2597 	pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2598 
2599 	prog = pi->progs + pi->num_progs;
2600 #ifndef __U_BOOT__
2601 	prog->redirects = NULL;
2602 #endif
2603 	prog->argv = NULL;
2604 #ifndef __U_BOOT__
2605 	prog->is_stopped = 0;
2606 #endif
2607 	prog->group = NULL;
2608 #ifndef __U_BOOT__
2609 	prog->glob_result.gl_pathv = NULL;
2610 	prog->family = pi;
2611 #endif
2612 	prog->sp = 0;
2613 	ctx->child = prog;
2614 	prog->type = ctx->type;
2615 
2616 	/* but ctx->pipe and ctx->list_head remain unchanged */
2617 	return 0;
2618 }
2619 
2620 static int done_pipe(struct p_context *ctx, pipe_style type)
2621 {
2622 	struct pipe *new_p;
2623 	done_command(ctx);  /* implicit closure of previous command */
2624 	debug_printf("done_pipe, type %d\n", type);
2625 	ctx->pipe->followup = type;
2626 	ctx->pipe->r_mode = ctx->w;
2627 	new_p=new_pipe();
2628 	ctx->pipe->next = new_p;
2629 	ctx->pipe = new_p;
2630 	ctx->child = NULL;
2631 	done_command(ctx);  /* set up new pipe to accept commands */
2632 	return 0;
2633 }
2634 
2635 #ifndef __U_BOOT__
2636 /* peek ahead in the in_str to find out if we have a "&n" construct,
2637  * as in "2>&1", that represents duplicating a file descriptor.
2638  * returns either -2 (syntax error), -1 (no &), or the number found.
2639  */
2640 static int redirect_dup_num(struct in_str *input)
2641 {
2642 	int ch, d=0, ok=0;
2643 	ch = b_peek(input);
2644 	if (ch != '&') return -1;
2645 
2646 	b_getch(input);  /* get the & */
2647 	ch=b_peek(input);
2648 	if (ch == '-') {
2649 		b_getch(input);
2650 		return -3;  /* "-" represents "close me" */
2651 	}
2652 	while (isdigit(ch)) {
2653 		d = d*10+(ch-'0');
2654 		ok=1;
2655 		b_getch(input);
2656 		ch = b_peek(input);
2657 	}
2658 	if (ok) return d;
2659 
2660 	error_msg("ambiguous redirect");
2661 	return -2;
2662 }
2663 
2664 /* If a redirect is immediately preceded by a number, that number is
2665  * supposed to tell which file descriptor to redirect.  This routine
2666  * looks for such preceding numbers.  In an ideal world this routine
2667  * needs to handle all the following classes of redirects...
2668  *     echo 2>foo     # redirects fd  2 to file "foo", nothing passed to echo
2669  *     echo 49>foo    # redirects fd 49 to file "foo", nothing passed to echo
2670  *     echo -2>foo    # redirects fd  1 to file "foo",    "-2" passed to echo
2671  *     echo 49x>foo   # redirects fd  1 to file "foo",   "49x" passed to echo
2672  * A -1 output from this program means no valid number was found, so the
2673  * caller should use the appropriate default for this redirection.
2674  */
2675 static int redirect_opt_num(o_string *o)
2676 {
2677 	int num;
2678 
2679 	if (o->length==0) return -1;
2680 	for(num=0; num<o->length; num++) {
2681 		if (!isdigit(*(o->data+num))) {
2682 			return -1;
2683 		}
2684 	}
2685 	/* reuse num (and save an int) */
2686 	num=atoi(o->data);
2687 	b_reset(o);
2688 	return num;
2689 }
2690 
2691 FILE *generate_stream_from_list(struct pipe *head)
2692 {
2693 	FILE *pf;
2694 #if 1
2695 	int pid, channel[2];
2696 	if (pipe(channel)<0) perror_msg_and_die("pipe");
2697 	pid=fork();
2698 	if (pid<0) {
2699 		perror_msg_and_die("fork");
2700 	} else if (pid==0) {
2701 		close(channel[0]);
2702 		if (channel[1] != 1) {
2703 			dup2(channel[1],1);
2704 			close(channel[1]);
2705 		}
2706 #if 0
2707 #define SURROGATE "surrogate response"
2708 		write(1,SURROGATE,sizeof(SURROGATE));
2709 		_exit(run_list(head));
2710 #else
2711 		_exit(run_list_real(head));   /* leaks memory */
2712 #endif
2713 	}
2714 	debug_printf("forked child %d\n",pid);
2715 	close(channel[1]);
2716 	pf = fdopen(channel[0],"r");
2717 	debug_printf("pipe on FILE *%p\n",pf);
2718 #else
2719 	free_pipe_list(head,0);
2720 	pf=popen("echo surrogate response","r");
2721 	debug_printf("started fake pipe on FILE *%p\n",pf);
2722 #endif
2723 	return pf;
2724 }
2725 
2726 /* this version hacked for testing purposes */
2727 /* return code is exit status of the process that is run. */
2728 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2729 {
2730 	int retcode;
2731 	o_string result=NULL_O_STRING;
2732 	struct p_context inner;
2733 	FILE *p;
2734 	struct in_str pipe_str;
2735 	initialize_context(&inner);
2736 
2737 	/* recursion to generate command */
2738 	retcode = parse_stream(&result, &inner, input, subst_end);
2739 	if (retcode != 0) return retcode;  /* syntax error or EOF */
2740 	done_word(&result, &inner);
2741 	done_pipe(&inner, PIPE_SEQ);
2742 	b_free(&result);
2743 
2744 	p=generate_stream_from_list(inner.list_head);
2745 	if (p==NULL) return 1;
2746 	mark_open(fileno(p));
2747 	setup_file_in_str(&pipe_str, p);
2748 
2749 	/* now send results of command back into original context */
2750 	retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2751 	/* XXX In case of a syntax error, should we try to kill the child?
2752 	 * That would be tough to do right, so just read until EOF. */
2753 	if (retcode == 1) {
2754 		while (b_getch(&pipe_str)!=EOF) { /* discard */ };
2755 	}
2756 
2757 	debug_printf("done reading from pipe, pclose()ing\n");
2758 	/* This is the step that wait()s for the child.  Should be pretty
2759 	 * safe, since we just read an EOF from its stdout.  We could try
2760 	 * to better, by using wait(), and keeping track of background jobs
2761 	 * at the same time.  That would be a lot of work, and contrary
2762 	 * to the KISS philosophy of this program. */
2763 	mark_closed(fileno(p));
2764 	retcode=pclose(p);
2765 	free_pipe_list(inner.list_head,0);
2766 	debug_printf("pclosed, retcode=%d\n",retcode);
2767 	/* XXX this process fails to trim a single trailing newline */
2768 	return retcode;
2769 }
2770 
2771 static int parse_group(o_string *dest, struct p_context *ctx,
2772 	struct in_str *input, int ch)
2773 {
2774 	int rcode, endch=0;
2775 	struct p_context sub;
2776 	struct child_prog *child = ctx->child;
2777 	if (child->argv) {
2778 		syntax();
2779 		return 1;  /* syntax error, groups and arglists don't mix */
2780 	}
2781 	initialize_context(&sub);
2782 	switch(ch) {
2783 		case '(': endch=')'; child->subshell=1; break;
2784 		case '{': endch='}'; break;
2785 		default: syntax();   /* really logic error */
2786 	}
2787 	rcode=parse_stream(dest,&sub,input,endch);
2788 	done_word(dest,&sub); /* finish off the final word in the subcontext */
2789 	done_pipe(&sub, PIPE_SEQ);  /* and the final command there, too */
2790 	child->group = sub.list_head;
2791 	return rcode;
2792 	/* child remains "open", available for possible redirects */
2793 }
2794 #endif
2795 
2796 /* basically useful version until someone wants to get fancier,
2797  * see the bash man page under "Parameter Expansion" */
2798 static char *lookup_param(char *src)
2799 {
2800 	char *p;
2801 
2802 	if (!src)
2803 		return NULL;
2804 
2805 		p = getenv(src);
2806 		if (!p)
2807 			p = get_local_var(src);
2808 
2809 	return p;
2810 }
2811 
2812 #ifdef __U_BOOT__
2813 static char *get_dollar_var(char ch)
2814 {
2815 	static char buf[40];
2816 
2817 	buf[0] = '\0';
2818 	switch (ch) {
2819 		case '?':
2820 			sprintf(buf, "%u", (unsigned int)last_return_code);
2821 			break;
2822 		default:
2823 			return NULL;
2824 	}
2825 	return buf;
2826 }
2827 #endif
2828 
2829 /* return code: 0 for OK, 1 for syntax error */
2830 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2831 {
2832 #ifndef __U_BOOT__
2833 	int i, advance=0;
2834 #else
2835 	int advance=0;
2836 #endif
2837 #ifndef __U_BOOT__
2838 	char sep[]=" ";
2839 #endif
2840 	int ch = input->peek(input);  /* first character after the $ */
2841 	debug_printf("handle_dollar: ch=%c\n",ch);
2842 	if (isalpha(ch)) {
2843 		b_addchr(dest, SPECIAL_VAR_SYMBOL);
2844 		ctx->child->sp++;
2845 		while(ch=b_peek(input),isalnum(ch) || ch=='_') {
2846 			b_getch(input);
2847 			b_addchr(dest,ch);
2848 		}
2849 		b_addchr(dest, SPECIAL_VAR_SYMBOL);
2850 #ifndef __U_BOOT__
2851 	} else if (isdigit(ch)) {
2852 		i = ch-'0';  /* XXX is $0 special? */
2853 		if (i<global_argc) {
2854 			parse_string(dest, ctx, global_argv[i]); /* recursion */
2855 		}
2856 		advance = 1;
2857 #endif
2858 	} else switch (ch) {
2859 #ifndef __U_BOOT__
2860 		case '$':
2861 			b_adduint(dest,getpid());
2862 			advance = 1;
2863 			break;
2864 		case '!':
2865 			if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2866 			advance = 1;
2867 			break;
2868 #endif
2869 		case '?':
2870 #ifndef __U_BOOT__
2871 			b_adduint(dest,last_return_code);
2872 #else
2873 			ctx->child->sp++;
2874 			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2875 			b_addchr(dest, '$');
2876 			b_addchr(dest, '?');
2877 			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2878 #endif
2879 			advance = 1;
2880 			break;
2881 #ifndef __U_BOOT__
2882 		case '#':
2883 			b_adduint(dest,global_argc ? global_argc-1 : 0);
2884 			advance = 1;
2885 			break;
2886 #endif
2887 		case '{':
2888 			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2889 			ctx->child->sp++;
2890 			b_getch(input);
2891 			/* XXX maybe someone will try to escape the '}' */
2892 			while(ch=b_getch(input),ch!=EOF && ch!='}') {
2893 				b_addchr(dest,ch);
2894 			}
2895 			if (ch != '}') {
2896 				syntax();
2897 				return 1;
2898 			}
2899 			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2900 			break;
2901 #ifndef __U_BOOT__
2902 		case '(':
2903 			b_getch(input);
2904 			process_command_subs(dest, ctx, input, ')');
2905 			break;
2906 		case '*':
2907 			sep[0]=ifs[0];
2908 			for (i=1; i<global_argc; i++) {
2909 				parse_string(dest, ctx, global_argv[i]);
2910 				if (i+1 < global_argc) parse_string(dest, ctx, sep);
2911 			}
2912 			break;
2913 		case '@':
2914 		case '-':
2915 		case '_':
2916 			/* still unhandled, but should be eventually */
2917 			error_msg("unhandled syntax: $%c",ch);
2918 			return 1;
2919 			break;
2920 #endif
2921 		default:
2922 			b_addqchr(dest,'$',dest->quote);
2923 	}
2924 	/* Eat the character if the flag was set.  If the compiler
2925 	 * is smart enough, we could substitute "b_getch(input);"
2926 	 * for all the "advance = 1;" above, and also end up with
2927 	 * a nice size-optimized program.  Hah!  That'll be the day.
2928 	 */
2929 	if (advance) b_getch(input);
2930 	return 0;
2931 }
2932 
2933 #ifndef __U_BOOT__
2934 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2935 {
2936 	struct in_str foo;
2937 	setup_string_in_str(&foo, src);
2938 	return parse_stream(dest, ctx, &foo, '\0');
2939 }
2940 #endif
2941 
2942 /* return code is 0 for normal exit, 1 for syntax error */
2943 int parse_stream(o_string *dest, struct p_context *ctx,
2944 	struct in_str *input, int end_trigger)
2945 {
2946 	unsigned int ch, m;
2947 #ifndef __U_BOOT__
2948 	int redir_fd;
2949 	redir_type redir_style;
2950 #endif
2951 	int next;
2952 
2953 	/* Only double-quote state is handled in the state variable dest->quote.
2954 	 * A single-quote triggers a bypass of the main loop until its mate is
2955 	 * found.  When recursing, quote state is passed in via dest->quote. */
2956 
2957 	debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2958 	while ((ch=b_getch(input))!=EOF) {
2959 		m = map[ch];
2960 #ifdef __U_BOOT__
2961 		if (input->__promptme == 0) return 1;
2962 #endif
2963 		next = (ch == '\n') ? 0 : b_peek(input);
2964 
2965 		debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d - %c\n",
2966 			ch >= ' ' ? ch : '.', ch, m,
2967 			dest->quote, ctx->stack == NULL ? '*' : '.');
2968 
2969 		if (m==0 || ((m==1 || m==2) && dest->quote)) {
2970 			b_addqchr(dest, ch, dest->quote);
2971 		} else {
2972 			if (m==2) {  /* unquoted IFS */
2973 				if (done_word(dest, ctx)) {
2974 					return 1;
2975 				}
2976 				/* If we aren't performing a substitution, treat a newline as a
2977 				 * command separator.  */
2978 				if (end_trigger != '\0' && ch=='\n')
2979 					done_pipe(ctx,PIPE_SEQ);
2980 			}
2981 			if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2982 				debug_printf("leaving parse_stream (triggered)\n");
2983 				return 0;
2984 			}
2985 #if 0
2986 			if (ch=='\n') {
2987 				/* Yahoo!  Time to run with it! */
2988 				done_pipe(ctx,PIPE_SEQ);
2989 				run_list(ctx->list_head);
2990 				initialize_context(ctx);
2991 			}
2992 #endif
2993 			if (m!=2) switch (ch) {
2994 		case '#':
2995 			if (dest->length == 0 && !dest->quote) {
2996 				while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
2997 			} else {
2998 				b_addqchr(dest, ch, dest->quote);
2999 			}
3000 			break;
3001 		case '\\':
3002 			if (next == EOF) {
3003 				syntax();
3004 				return 1;
3005 			}
3006 			b_addqchr(dest, '\\', dest->quote);
3007 			b_addqchr(dest, b_getch(input), dest->quote);
3008 			break;
3009 		case '$':
3010 			if (handle_dollar(dest, ctx, input)!=0) return 1;
3011 			break;
3012 		case '\'':
3013 			dest->nonnull = 1;
3014 			while(ch=b_getch(input),ch!=EOF && ch!='\'') {
3015 #ifdef __U_BOOT__
3016 				if(input->__promptme == 0) return 1;
3017 #endif
3018 				b_addchr(dest,ch);
3019 			}
3020 			if (ch==EOF) {
3021 				syntax();
3022 				return 1;
3023 			}
3024 			break;
3025 		case '"':
3026 			dest->nonnull = 1;
3027 			dest->quote = !dest->quote;
3028 			break;
3029 #ifndef __U_BOOT__
3030 		case '`':
3031 			process_command_subs(dest, ctx, input, '`');
3032 			break;
3033 		case '>':
3034 			redir_fd = redirect_opt_num(dest);
3035 			done_word(dest, ctx);
3036 			redir_style=REDIRECT_OVERWRITE;
3037 			if (next == '>') {
3038 				redir_style=REDIRECT_APPEND;
3039 				b_getch(input);
3040 			} else if (next == '(') {
3041 				syntax();   /* until we support >(list) Process Substitution */
3042 				return 1;
3043 			}
3044 			setup_redirect(ctx, redir_fd, redir_style, input);
3045 			break;
3046 		case '<':
3047 			redir_fd = redirect_opt_num(dest);
3048 			done_word(dest, ctx);
3049 			redir_style=REDIRECT_INPUT;
3050 			if (next == '<') {
3051 				redir_style=REDIRECT_HEREIS;
3052 				b_getch(input);
3053 			} else if (next == '>') {
3054 				redir_style=REDIRECT_IO;
3055 				b_getch(input);
3056 			} else if (next == '(') {
3057 				syntax();   /* until we support <(list) Process Substitution */
3058 				return 1;
3059 			}
3060 			setup_redirect(ctx, redir_fd, redir_style, input);
3061 			break;
3062 #endif
3063 		case ';':
3064 			done_word(dest, ctx);
3065 			done_pipe(ctx,PIPE_SEQ);
3066 			break;
3067 		case '&':
3068 			done_word(dest, ctx);
3069 			if (next=='&') {
3070 				b_getch(input);
3071 				done_pipe(ctx,PIPE_AND);
3072 			} else {
3073 #ifndef __U_BOOT__
3074 				done_pipe(ctx,PIPE_BG);
3075 #else
3076 				syntax_err();
3077 				return 1;
3078 #endif
3079 			}
3080 			break;
3081 		case '|':
3082 			done_word(dest, ctx);
3083 			if (next=='|') {
3084 				b_getch(input);
3085 				done_pipe(ctx,PIPE_OR);
3086 			} else {
3087 				/* we could pick up a file descriptor choice here
3088 				 * with redirect_opt_num(), but bash doesn't do it.
3089 				 * "echo foo 2| cat" yields "foo 2". */
3090 #ifndef __U_BOOT__
3091 				done_command(ctx);
3092 #else
3093 				syntax_err();
3094 				return 1;
3095 #endif
3096 			}
3097 			break;
3098 #ifndef __U_BOOT__
3099 		case '(':
3100 		case '{':
3101 			if (parse_group(dest, ctx, input, ch)!=0) return 1;
3102 			break;
3103 		case ')':
3104 		case '}':
3105 			syntax();   /* Proper use of this character caught by end_trigger */
3106 			return 1;
3107 			break;
3108 #endif
3109 		default:
3110 			syntax();   /* this is really an internal logic error */
3111 			return 1;
3112 			}
3113 		}
3114 	}
3115 	/* complain if quote?  No, maybe we just finished a command substitution
3116 	 * that was quoted.  Example:
3117 	 * $ echo "`cat foo` plus more"
3118 	 * and we just got the EOF generated by the subshell that ran "cat foo"
3119 	 * The only real complaint is if we got an EOF when end_trigger != '\0',
3120 	 * that is, we were really supposed to get end_trigger, and never got
3121 	 * one before the EOF.  Can't use the standard "syntax error" return code,
3122 	 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
3123 	debug_printf("leaving parse_stream (EOF)\n");
3124 	if (end_trigger != '\0') return -1;
3125 	return 0;
3126 }
3127 
3128 void mapset(const unsigned char *set, int code)
3129 {
3130 	const unsigned char *s;
3131 	for (s=set; *s; s++) map[*s] = code;
3132 }
3133 
3134 void update_ifs_map(void)
3135 {
3136 	/* char *ifs and char map[256] are both globals. */
3137 	ifs = (uchar *)getenv("IFS");
3138 	if (ifs == NULL) ifs=(uchar *)" \t\n";
3139 	/* Precompute a list of 'flow through' behavior so it can be treated
3140 	 * quickly up front.  Computation is necessary because of IFS.
3141 	 * Special case handling of IFS == " \t\n" is not implemented.
3142 	 * The map[] array only really needs two bits each, and on most machines
3143 	 * that would be faster because of the reduced L1 cache footprint.
3144 	 */
3145 	memset(map,0,sizeof(map)); /* most characters flow through always */
3146 #ifndef __U_BOOT__
3147 	mapset((uchar *)"\\$'\"`", 3);      /* never flow through */
3148 	mapset((uchar *)"<>;&|(){}#", 1);   /* flow through if quoted */
3149 #else
3150 	mapset((uchar *)"\\$'\"", 3);       /* never flow through */
3151 	mapset((uchar *)";&|#", 1);         /* flow through if quoted */
3152 #endif
3153 	mapset(ifs, 2);            /* also flow through if quoted */
3154 }
3155 
3156 /* most recursion does not come through here, the exeception is
3157  * from builtin_source() */
3158 int parse_stream_outer(struct in_str *inp, int flag)
3159 {
3160 
3161 	struct p_context ctx;
3162 	o_string temp=NULL_O_STRING;
3163 	int rcode;
3164 #ifdef __U_BOOT__
3165 	int code = 0;
3166 #endif
3167 	do {
3168 		ctx.type = flag;
3169 		initialize_context(&ctx);
3170 		update_ifs_map();
3171 		if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset((uchar *)";$&|", 0);
3172 		inp->promptmode=1;
3173 		rcode = parse_stream(&temp, &ctx, inp, '\n');
3174 #ifdef __U_BOOT__
3175 		if (rcode == 1) flag_repeat = 0;
3176 #endif
3177 		if (rcode != 1 && ctx.old_flag != 0) {
3178 			syntax();
3179 #ifdef __U_BOOT__
3180 			flag_repeat = 0;
3181 #endif
3182 		}
3183 		if (rcode != 1 && ctx.old_flag == 0) {
3184 			done_word(&temp, &ctx);
3185 			done_pipe(&ctx,PIPE_SEQ);
3186 #ifndef __U_BOOT__
3187 			run_list(ctx.list_head);
3188 #else
3189 			code = run_list(ctx.list_head);
3190 			if (code == -2) {	/* exit */
3191 				b_free(&temp);
3192 				code = 0;
3193 				/* XXX hackish way to not allow exit from main loop */
3194 				if (inp->peek == file_peek) {
3195 					printf("exit not allowed from main input shell.\n");
3196 					continue;
3197 				}
3198 				break;
3199 			}
3200 			if (code == -1)
3201 			    flag_repeat = 0;
3202 #endif
3203 		} else {
3204 			if (ctx.old_flag != 0) {
3205 				free(ctx.stack);
3206 				b_reset(&temp);
3207 			}
3208 #ifdef __U_BOOT__
3209 			if (inp->__promptme == 0) printf("<INTERRUPT>\n");
3210 			inp->__promptme = 1;
3211 #endif
3212 			temp.nonnull = 0;
3213 			temp.quote = 0;
3214 			inp->p = NULL;
3215 			free_pipe_list(ctx.list_head,0);
3216 		}
3217 		b_free(&temp);
3218 	} while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP));   /* loop on syntax errors, return on EOF */
3219 #ifndef __U_BOOT__
3220 	return 0;
3221 #else
3222 	return (code != 0) ? 1 : 0;
3223 #endif /* __U_BOOT__ */
3224 }
3225 
3226 #ifndef __U_BOOT__
3227 static int parse_string_outer(const char *s, int flag)
3228 #else
3229 int parse_string_outer(char *s, int flag)
3230 #endif	/* __U_BOOT__ */
3231 {
3232 	struct in_str input;
3233 #ifdef __U_BOOT__
3234 	char *p = NULL;
3235 	int rcode;
3236 	if ( !s || !*s)
3237 		return 1;
3238 	if (!(p = strchr(s, '\n')) || *++p) {
3239 		p = xmalloc(strlen(s) + 2);
3240 		strcpy(p, s);
3241 		strcat(p, "\n");
3242 		setup_string_in_str(&input, p);
3243 		rcode = parse_stream_outer(&input, flag);
3244 		free(p);
3245 		return rcode;
3246 	} else {
3247 #endif
3248 	setup_string_in_str(&input, s);
3249 	return parse_stream_outer(&input, flag);
3250 #ifdef __U_BOOT__
3251 	}
3252 #endif
3253 }
3254 
3255 #ifndef __U_BOOT__
3256 static int parse_file_outer(FILE *f)
3257 #else
3258 int parse_file_outer(void)
3259 #endif
3260 {
3261 	int rcode;
3262 	struct in_str input;
3263 #ifndef __U_BOOT__
3264 	setup_file_in_str(&input, f);
3265 #else
3266 	setup_file_in_str(&input);
3267 #endif
3268 	rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
3269 	return rcode;
3270 }
3271 
3272 #ifdef __U_BOOT__
3273 #ifndef CONFIG_RELOC_FIXUP_WORKS
3274 static void u_boot_hush_reloc(void)
3275 {
3276 	unsigned long addr;
3277 	struct reserved_combo *r;
3278 
3279 	for (r=reserved_list; r<reserved_list+NRES; r++) {
3280 		addr = (ulong) (r->literal) + gd->reloc_off;
3281 		r->literal = (char *)addr;
3282 	}
3283 }
3284 #endif
3285 
3286 int u_boot_hush_start(void)
3287 {
3288 	if (top_vars == NULL) {
3289 		top_vars = malloc(sizeof(struct variables));
3290 		top_vars->name = "HUSH_VERSION";
3291 		top_vars->value = "0.01";
3292 		top_vars->next = 0;
3293 		top_vars->flg_export = 0;
3294 		top_vars->flg_read_only = 1;
3295 #ifndef CONFIG_RELOC_FIXUP_WORKS
3296 		u_boot_hush_reloc();
3297 #endif
3298 	}
3299 	return 0;
3300 }
3301 
3302 static void *xmalloc(size_t size)
3303 {
3304 	void *p = NULL;
3305 
3306 	if (!(p = malloc(size))) {
3307 	    printf("ERROR : memory not allocated\n");
3308 	    for(;;);
3309 	}
3310 	return p;
3311 }
3312 
3313 static void *xrealloc(void *ptr, size_t size)
3314 {
3315 	void *p = NULL;
3316 
3317 	if (!(p = realloc(ptr, size))) {
3318 	    printf("ERROR : memory not allocated\n");
3319 	    for(;;);
3320 	}
3321 	return p;
3322 }
3323 #endif /* __U_BOOT__ */
3324 
3325 #ifndef __U_BOOT__
3326 /* Make sure we have a controlling tty.  If we get started under a job
3327  * aware app (like bash for example), make sure we are now in charge so
3328  * we don't fight over who gets the foreground */
3329 static void setup_job_control(void)
3330 {
3331 	static pid_t shell_pgrp;
3332 	/* Loop until we are in the foreground.  */
3333 	while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
3334 		kill (- shell_pgrp, SIGTTIN);
3335 
3336 	/* Ignore interactive and job-control signals.  */
3337 	signal(SIGINT, SIG_IGN);
3338 	signal(SIGQUIT, SIG_IGN);
3339 	signal(SIGTERM, SIG_IGN);
3340 	signal(SIGTSTP, SIG_IGN);
3341 	signal(SIGTTIN, SIG_IGN);
3342 	signal(SIGTTOU, SIG_IGN);
3343 	signal(SIGCHLD, SIG_IGN);
3344 
3345 	/* Put ourselves in our own process group.  */
3346 	setsid();
3347 	shell_pgrp = getpid ();
3348 	setpgid (shell_pgrp, shell_pgrp);
3349 
3350 	/* Grab control of the terminal.  */
3351 	tcsetpgrp(shell_terminal, shell_pgrp);
3352 }
3353 
3354 int hush_main(int argc, char **argv)
3355 {
3356 	int opt;
3357 	FILE *input;
3358 	char **e = environ;
3359 
3360 	/* XXX what should these be while sourcing /etc/profile? */
3361 	global_argc = argc;
3362 	global_argv = argv;
3363 
3364 	/* (re?) initialize globals.  Sometimes hush_main() ends up calling
3365 	 * hush_main(), therefore we cannot rely on the BSS to zero out this
3366 	 * stuff.  Reset these to 0 every time. */
3367 	ifs = NULL;
3368 	/* map[] is taken care of with call to update_ifs_map() */
3369 	fake_mode = 0;
3370 	interactive = 0;
3371 	close_me_head = NULL;
3372 	last_bg_pid = 0;
3373 	job_list = NULL;
3374 	last_jobid = 0;
3375 
3376 	/* Initialize some more globals to non-zero values */
3377 	set_cwd();
3378 #ifdef CONFIG_FEATURE_COMMAND_EDITING
3379 	cmdedit_set_initial_prompt();
3380 #else
3381 	PS1 = NULL;
3382 #endif
3383 	PS2 = "> ";
3384 
3385 	/* initialize our shell local variables with the values
3386 	 * currently living in the environment */
3387 	if (e) {
3388 		for (; *e; e++)
3389 			set_local_var(*e, 2);   /* without call putenv() */
3390 	}
3391 
3392 	last_return_code=EXIT_SUCCESS;
3393 
3394 
3395 	if (argv[0] && argv[0][0] == '-') {
3396 		debug_printf("\nsourcing /etc/profile\n");
3397 		if ((input = fopen("/etc/profile", "r")) != NULL) {
3398 			mark_open(fileno(input));
3399 			parse_file_outer(input);
3400 			mark_closed(fileno(input));
3401 			fclose(input);
3402 		}
3403 	}
3404 	input=stdin;
3405 
3406 	while ((opt = getopt(argc, argv, "c:xif")) > 0) {
3407 		switch (opt) {
3408 			case 'c':
3409 				{
3410 					global_argv = argv+optind;
3411 					global_argc = argc-optind;
3412 					opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
3413 					goto final_return;
3414 				}
3415 				break;
3416 			case 'i':
3417 				interactive++;
3418 				break;
3419 			case 'f':
3420 				fake_mode++;
3421 				break;
3422 			default:
3423 #ifndef BB_VER
3424 				fprintf(stderr, "Usage: sh [FILE]...\n"
3425 						"   or: sh -c command [args]...\n\n");
3426 				exit(EXIT_FAILURE);
3427 #else
3428 				show_usage();
3429 #endif
3430 		}
3431 	}
3432 	/* A shell is interactive if the `-i' flag was given, or if all of
3433 	 * the following conditions are met:
3434 	 *	  no -c command
3435 	 *    no arguments remaining or the -s flag given
3436 	 *    standard input is a terminal
3437 	 *    standard output is a terminal
3438 	 *    Refer to Posix.2, the description of the `sh' utility. */
3439 	if (argv[optind]==NULL && input==stdin &&
3440 			isatty(fileno(stdin)) && isatty(fileno(stdout))) {
3441 		interactive++;
3442 	}
3443 
3444 	debug_printf("\ninteractive=%d\n", interactive);
3445 	if (interactive) {
3446 		/* Looks like they want an interactive shell */
3447 #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
3448 		printf( "\n\n" BB_BANNER " hush - the humble shell v0.01 (testing)\n");
3449 		printf( "Enter 'help' for a list of built-in commands.\n\n");
3450 #endif
3451 		setup_job_control();
3452 	}
3453 
3454 	if (argv[optind]==NULL) {
3455 		opt=parse_file_outer(stdin);
3456 		goto final_return;
3457 	}
3458 
3459 	debug_printf("\nrunning script '%s'\n", argv[optind]);
3460 	global_argv = argv+optind;
3461 	global_argc = argc-optind;
3462 	input = xfopen(argv[optind], "r");
3463 	opt = parse_file_outer(input);
3464 
3465 #ifdef CONFIG_FEATURE_CLEAN_UP
3466 	fclose(input);
3467 	if (cwd && cwd != unknown)
3468 		free((char*)cwd);
3469 	{
3470 		struct variables *cur, *tmp;
3471 		for(cur = top_vars; cur; cur = tmp) {
3472 			tmp = cur->next;
3473 			if (!cur->flg_read_only) {
3474 				free(cur->name);
3475 				free(cur->value);
3476 				free(cur);
3477 			}
3478 		}
3479 	}
3480 #endif
3481 
3482 final_return:
3483 	return(opt?opt:last_return_code);
3484 }
3485 #endif
3486 
3487 static char *insert_var_value(char *inp)
3488 {
3489 	int res_str_len = 0;
3490 	int len;
3491 	int done = 0;
3492 	char *p, *p1, *res_str = NULL;
3493 
3494 	while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
3495 		if (p != inp) {
3496 			len = p - inp;
3497 			res_str = xrealloc(res_str, (res_str_len + len));
3498 			strncpy((res_str + res_str_len), inp, len);
3499 			res_str_len += len;
3500 		}
3501 		inp = ++p;
3502 		p = strchr(inp, SPECIAL_VAR_SYMBOL);
3503 		*p = '\0';
3504 		if ((p1 = lookup_param(inp))) {
3505 			len = res_str_len + strlen(p1);
3506 			res_str = xrealloc(res_str, (1 + len));
3507 			strcpy((res_str + res_str_len), p1);
3508 			res_str_len = len;
3509 		}
3510 		*p = SPECIAL_VAR_SYMBOL;
3511 		inp = ++p;
3512 		done = 1;
3513 	}
3514 	if (done) {
3515 		res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
3516 		strcpy((res_str + res_str_len), inp);
3517 		while ((p = strchr(res_str, '\n'))) {
3518 			*p = ' ';
3519 		}
3520 	}
3521 	return (res_str == NULL) ? inp : res_str;
3522 }
3523 
3524 static char **make_list_in(char **inp, char *name)
3525 {
3526 	int len, i;
3527 	int name_len = strlen(name);
3528 	int n = 0;
3529 	char **list;
3530 	char *p1, *p2, *p3;
3531 
3532 	/* create list of variable values */
3533 	list = xmalloc(sizeof(*list));
3534 	for (i = 0; inp[i]; i++) {
3535 		p3 = insert_var_value(inp[i]);
3536 		p1 = p3;
3537 		while (*p1) {
3538 			if ((*p1 == ' ')) {
3539 				p1++;
3540 				continue;
3541 			}
3542 			if ((p2 = strchr(p1, ' '))) {
3543 				len = p2 - p1;
3544 			} else {
3545 				len = strlen(p1);
3546 				p2 = p1 + len;
3547 			}
3548 			/* we use n + 2 in realloc for list,because we add
3549 			 * new element and then we will add NULL element */
3550 			list = xrealloc(list, sizeof(*list) * (n + 2));
3551 			list[n] = xmalloc(2 + name_len + len);
3552 			strcpy(list[n], name);
3553 			strcat(list[n], "=");
3554 			strncat(list[n], p1, len);
3555 			list[n++][name_len + len + 1] = '\0';
3556 			p1 = p2;
3557 		}
3558 		if (p3 != inp[i]) free(p3);
3559 	}
3560 	list[n] = NULL;
3561 	return list;
3562 }
3563 
3564 /* Make new string for parser */
3565 static char * make_string(char ** inp)
3566 {
3567 	char *p;
3568 	char *str = NULL;
3569 	int n;
3570 	int len = 2;
3571 
3572 	for (n = 0; inp[n]; n++) {
3573 		p = insert_var_value(inp[n]);
3574 		str = xrealloc(str, (len + strlen(p)));
3575 		if (n) {
3576 			strcat(str, " ");
3577 		} else {
3578 			*str = '\0';
3579 		}
3580 		strcat(str, p);
3581 		len = strlen(str) + 3;
3582 		if (p != inp[n]) free(p);
3583 	}
3584 	len = strlen(str);
3585 	*(str + len) = '\n';
3586 	*(str + len + 1) = '\0';
3587 	return str;
3588 }
3589 
3590 #ifdef __U_BOOT__
3591 int do_showvar (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
3592 {
3593 	int i, k;
3594 	int rcode = 0;
3595 	struct variables *cur;
3596 
3597 	if (argc == 1) {		/* Print all env variables	*/
3598 		for (cur = top_vars; cur; cur = cur->next) {
3599 			printf ("%s=%s\n", cur->name, cur->value);
3600 			if (ctrlc ()) {
3601 				puts ("\n ** Abort\n");
3602 				return 1;
3603 			}
3604 		}
3605 		return 0;
3606 	}
3607 	for (i = 1; i < argc; ++i) {	/* print single env variables	*/
3608 		char *name = argv[i];
3609 
3610 		k = -1;
3611 		for (cur = top_vars; cur; cur = cur->next) {
3612 			if(strcmp (cur->name, name) == 0) {
3613 				k = 0;
3614 				printf ("%s=%s\n", cur->name, cur->value);
3615 			}
3616 			if (ctrlc ()) {
3617 				puts ("\n ** Abort\n");
3618 				return 1;
3619 			}
3620 		}
3621 		if (k < 0) {
3622 			printf ("## Error: \"%s\" not defined\n", name);
3623 			rcode ++;
3624 		}
3625 	}
3626 	return rcode;
3627 }
3628 
3629 U_BOOT_CMD(
3630 	showvar, CONFIG_SYS_MAXARGS, 1,	do_showvar,
3631 	"print local hushshell variables",
3632 	"\n    - print values of all hushshell variables\n"
3633 	"showvar name ...\n"
3634 	"    - print value of hushshell variable 'name'"
3635 );
3636 
3637 #endif
3638 /****************************************************************************/
3639