xref: /openbmc/u-boot/common/cli_hush.c (revision 32c81ea6)
1 /*
2  * sh.c -- a prototype Bourne shell grammar parser
3  *      Intended to follow the original Thompson and Ritchie
4  *      "small and simple is beautiful" philosophy, which
5  *      incidentally is a good match to today's BusyBox.
6  *
7  * Copyright (C) 2000,2001  Larry Doolittle  <larry@doolittle.boa.org>
8  *
9  * Credits:
10  *      The parser routines proper are all original material, first
11  *      written Dec 2000 and Jan 2001 by Larry Doolittle.
12  *      The execution engine, the builtins, and much of the underlying
13  *      support has been adapted from busybox-0.49pre's lash,
14  *      which is Copyright (C) 2000 by Lineo, Inc., and
15  *      written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>.
16  *      That, in turn, is based in part on ladsh.c, by Michael K. Johnson and
17  *      Erik W. Troan, which they placed in the public domain.  I don't know
18  *      how much of the Johnson/Troan code has survived the repeated rewrites.
19  * Other credits:
20  *      b_addchr() derived from similar w_addchar function in glibc-2.2
21  *      setup_redirect(), redirect_opt_num(), and big chunks of main()
22  *        and many builtins derived from contributions by Erik Andersen
23  *      miscellaneous bugfixes from Matt Kraai
24  *
25  * There are two big (and related) architecture differences between
26  * this parser and the lash parser.  One is that this version is
27  * actually designed from the ground up to understand nearly all
28  * of the Bourne grammar.  The second, consequential change is that
29  * the parser and input reader have been turned inside out.  Now,
30  * the parser is in control, and asks for input as needed.  The old
31  * way had the input reader in control, and it asked for parsing to
32  * take place as needed.  The new way makes it much easier to properly
33  * handle the recursion implicit in the various substitutions, especially
34  * across continuation lines.
35  *
36  * Bash grammar not implemented: (how many of these were in original sh?)
37  *      $@ (those sure look like weird quoting rules)
38  *      $_
39  *      ! negation operator for pipes
40  *      &> and >& redirection of stdout+stderr
41  *      Brace Expansion
42  *      Tilde Expansion
43  *      fancy forms of Parameter Expansion
44  *      aliases
45  *      Arithmetic Expansion
46  *      <(list) and >(list) Process Substitution
47  *      reserved words: case, esac, select, function
48  *      Here Documents ( << word )
49  *      Functions
50  * Major bugs:
51  *      job handling woefully incomplete and buggy
52  *      reserved word execution woefully incomplete and buggy
53  * to-do:
54  *      port selected bugfixes from post-0.49 busybox lash - done?
55  *      finish implementing reserved words: for, while, until, do, done
56  *      change { and } from special chars to reserved words
57  *      builtins: break, continue, eval, return, set, trap, ulimit
58  *      test magic exec
59  *      handle children going into background
60  *      clean up recognition of null pipes
61  *      check setting of global_argc and global_argv
62  *      control-C handling, probably with longjmp
63  *      follow IFS rules more precisely, including update semantics
64  *      figure out what to do with backslash-newline
65  *      explain why we use signal instead of sigaction
66  *      propagate syntax errors, die on resource errors?
67  *      continuation lines, both explicit and implicit - done?
68  *      memory leak finding and plugging - done?
69  *      more testing, especially quoting rules and redirection
70  *      document how quoting rules not precisely followed for variable assignments
71  *      maybe change map[] to use 2-bit entries
72  *      (eventually) remove all the printf's
73  *
74  * SPDX-License-Identifier:	GPL-2.0+
75  */
76 
77 #define __U_BOOT__
78 #ifdef __U_BOOT__
79 #include <malloc.h>         /* malloc, free, realloc*/
80 #include <linux/ctype.h>    /* isalpha, isdigit */
81 #include <common.h>        /* readline */
82 #include <bootretry.h>
83 #include <cli.h>
84 #include <cli_hush.h>
85 #include <command.h>        /* find_cmd */
86 #ifndef CONFIG_SYS_PROMPT_HUSH_PS2
87 #define CONFIG_SYS_PROMPT_HUSH_PS2	"> "
88 #endif
89 #endif
90 #ifndef __U_BOOT__
91 #include <ctype.h>     /* isalpha, isdigit */
92 #include <unistd.h>    /* getpid */
93 #include <stdlib.h>    /* getenv, atoi */
94 #include <string.h>    /* strchr */
95 #include <stdio.h>     /* popen etc. */
96 #include <glob.h>      /* glob, of course */
97 #include <stdarg.h>    /* va_list */
98 #include <errno.h>
99 #include <fcntl.h>
100 #include <getopt.h>    /* should be pretty obvious */
101 
102 #include <sys/stat.h>  /* ulimit */
103 #include <sys/types.h>
104 #include <sys/wait.h>
105 #include <signal.h>
106 
107 /* #include <dmalloc.h> */
108 
109 #if 1
110 #include "busybox.h"
111 #include "cmdedit.h"
112 #else
113 #define applet_name "hush"
114 #include "standalone.h"
115 #define hush_main main
116 #undef CONFIG_FEATURE_SH_FANCY_PROMPT
117 #define BB_BANNER
118 #endif
119 #endif
120 #define SPECIAL_VAR_SYMBOL 03
121 #define SUBSTED_VAR_SYMBOL 04
122 #ifndef __U_BOOT__
123 #define FLAG_EXIT_FROM_LOOP 1
124 #define FLAG_PARSE_SEMICOLON (1 << 1)		/* symbol ';' is special for parser */
125 #define FLAG_REPARSING       (1 << 2)		/* >= 2nd pass */
126 
127 #endif
128 
129 #ifdef __U_BOOT__
130 DECLARE_GLOBAL_DATA_PTR;
131 
132 #define EXIT_SUCCESS 0
133 #define EOF -1
134 #define syntax() syntax_err()
135 #define xstrdup strdup
136 #define error_msg printf
137 #else
138 typedef enum {
139 	REDIRECT_INPUT     = 1,
140 	REDIRECT_OVERWRITE = 2,
141 	REDIRECT_APPEND    = 3,
142 	REDIRECT_HEREIS    = 4,
143 	REDIRECT_IO        = 5
144 } redir_type;
145 
146 /* The descrip member of this structure is only used to make debugging
147  * output pretty */
148 struct {int mode; int default_fd; char *descrip;} redir_table[] = {
149 	{ 0,                         0, "()" },
150 	{ O_RDONLY,                  0, "<"  },
151 	{ O_CREAT|O_TRUNC|O_WRONLY,  1, ">"  },
152 	{ O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
153 	{ O_RDONLY,                 -1, "<<" },
154 	{ O_RDWR,                    1, "<>" }
155 };
156 #endif
157 
158 typedef enum {
159 	PIPE_SEQ = 1,
160 	PIPE_AND = 2,
161 	PIPE_OR  = 3,
162 	PIPE_BG  = 4,
163 } pipe_style;
164 
165 /* might eventually control execution */
166 typedef enum {
167 	RES_NONE  = 0,
168 	RES_IF    = 1,
169 	RES_THEN  = 2,
170 	RES_ELIF  = 3,
171 	RES_ELSE  = 4,
172 	RES_FI    = 5,
173 	RES_FOR   = 6,
174 	RES_WHILE = 7,
175 	RES_UNTIL = 8,
176 	RES_DO    = 9,
177 	RES_DONE  = 10,
178 	RES_XXXX  = 11,
179 	RES_IN    = 12,
180 	RES_SNTX  = 13
181 } reserved_style;
182 #define FLAG_END   (1<<RES_NONE)
183 #define FLAG_IF    (1<<RES_IF)
184 #define FLAG_THEN  (1<<RES_THEN)
185 #define FLAG_ELIF  (1<<RES_ELIF)
186 #define FLAG_ELSE  (1<<RES_ELSE)
187 #define FLAG_FI    (1<<RES_FI)
188 #define FLAG_FOR   (1<<RES_FOR)
189 #define FLAG_WHILE (1<<RES_WHILE)
190 #define FLAG_UNTIL (1<<RES_UNTIL)
191 #define FLAG_DO    (1<<RES_DO)
192 #define FLAG_DONE  (1<<RES_DONE)
193 #define FLAG_IN    (1<<RES_IN)
194 #define FLAG_START (1<<RES_XXXX)
195 
196 /* This holds pointers to the various results of parsing */
197 struct p_context {
198 	struct child_prog *child;
199 	struct pipe *list_head;
200 	struct pipe *pipe;
201 #ifndef __U_BOOT__
202 	struct redir_struct *pending_redirect;
203 #endif
204 	reserved_style w;
205 	int old_flag;				/* for figuring out valid reserved words */
206 	struct p_context *stack;
207 	int type;			/* define type of parser : ";$" common or special symbol */
208 	/* How about quoting status? */
209 };
210 
211 #ifndef __U_BOOT__
212 struct redir_struct {
213 	redir_type type;			/* type of redirection */
214 	int fd;						/* file descriptor being redirected */
215 	int dup;					/* -1, or file descriptor being duplicated */
216 	struct redir_struct *next;	/* pointer to the next redirect in the list */
217 	glob_t word;				/* *word.gl_pathv is the filename */
218 };
219 #endif
220 
221 struct child_prog {
222 #ifndef __U_BOOT__
223 	pid_t pid;					/* 0 if exited */
224 #endif
225 	char **argv;				/* program name and arguments */
226 	/* was quoted when parsed; copy of struct o_string.nonnull field */
227 	int *argv_nonnull;
228 #ifdef __U_BOOT__
229 	int    argc;                            /* number of program arguments */
230 #endif
231 	struct pipe *group;			/* if non-NULL, first in group or subshell */
232 #ifndef __U_BOOT__
233 	int subshell;				/* flag, non-zero if group must be forked */
234 	struct redir_struct *redirects;	/* I/O redirections */
235 	glob_t glob_result;			/* result of parameter globbing */
236 	int is_stopped;				/* is the program currently running? */
237 	struct pipe *family;		/* pointer back to the child's parent pipe */
238 #endif
239 	int sp;				/* number of SPECIAL_VAR_SYMBOL */
240 	int type;
241 };
242 
243 struct pipe {
244 #ifndef __U_BOOT__
245 	int jobid;					/* job number */
246 #endif
247 	int num_progs;				/* total number of programs in job */
248 #ifndef __U_BOOT__
249 	int running_progs;			/* number of programs running */
250 	char *text;					/* name of job */
251 	char *cmdbuf;				/* buffer various argv's point into */
252 	pid_t pgrp;					/* process group ID for the job */
253 #endif
254 	struct child_prog *progs;	/* array of commands in pipe */
255 	struct pipe *next;			/* to track background commands */
256 #ifndef __U_BOOT__
257 	int stopped_progs;			/* number of programs alive, but stopped */
258 	int job_context;			/* bitmask defining current context */
259 #endif
260 	pipe_style followup;		/* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
261 	reserved_style r_mode;		/* supports if, for, while, until */
262 };
263 
264 #ifndef __U_BOOT__
265 struct close_me {
266 	int fd;
267 	struct close_me *next;
268 };
269 #endif
270 
271 struct variables {
272 	char *name;
273 	char *value;
274 	int flg_export;
275 	int flg_read_only;
276 	struct variables *next;
277 };
278 
279 /* globals, connect us to the outside world
280  * the first three support $?, $#, and $1 */
281 #ifndef __U_BOOT__
282 char **global_argv;
283 unsigned int global_argc;
284 #endif
285 static unsigned int last_return_code;
286 #ifndef __U_BOOT__
287 extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
288 #endif
289 
290 /* "globals" within this file */
291 static uchar *ifs;
292 static char map[256];
293 #ifndef __U_BOOT__
294 static int fake_mode;
295 static int interactive;
296 static struct close_me *close_me_head;
297 static const char *cwd;
298 static struct pipe *job_list;
299 static unsigned int last_bg_pid;
300 static unsigned int last_jobid;
301 static unsigned int shell_terminal;
302 static char *PS1;
303 static char *PS2;
304 struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
305 struct variables *top_vars = &shell_ver;
306 #else
307 static int flag_repeat = 0;
308 static int do_repeat = 0;
309 static struct variables *top_vars = NULL ;
310 #endif /*__U_BOOT__ */
311 
312 #define B_CHUNK (100)
313 #define B_NOSPAC 1
314 
315 typedef struct {
316 	char *data;
317 	int length;
318 	int maxlen;
319 	int quote;
320 	int nonnull;
321 } o_string;
322 #define NULL_O_STRING {NULL,0,0,0,0}
323 /* used for initialization:
324 	o_string foo = NULL_O_STRING; */
325 
326 /* I can almost use ordinary FILE *.  Is open_memstream() universally
327  * available?  Where is it documented? */
328 struct in_str {
329 	const char *p;
330 #ifndef __U_BOOT__
331 	char peek_buf[2];
332 #endif
333 	int __promptme;
334 	int promptmode;
335 #ifndef __U_BOOT__
336 	FILE *file;
337 #endif
338 	int (*get) (struct in_str *);
339 	int (*peek) (struct in_str *);
340 };
341 #define b_getch(input) ((input)->get(input))
342 #define b_peek(input) ((input)->peek(input))
343 
344 #ifndef __U_BOOT__
345 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
346 
347 struct built_in_command {
348 	char *cmd;					/* name */
349 	char *descr;				/* description */
350 	int (*function) (struct child_prog *);	/* function ptr */
351 };
352 #endif
353 
354 /* define DEBUG_SHELL for debugging output (obviously ;-)) */
355 #if 0
356 #define DEBUG_SHELL
357 #endif
358 
359 /* This should be in utility.c */
360 #ifdef DEBUG_SHELL
361 #ifndef __U_BOOT__
362 static void debug_printf(const char *format, ...)
363 {
364 	va_list args;
365 	va_start(args, format);
366 	vfprintf(stderr, format, args);
367 	va_end(args);
368 }
369 #else
370 #define debug_printf(fmt,args...)	printf (fmt ,##args)
371 #endif
372 #else
373 static inline void debug_printf(const char *format, ...) { }
374 #endif
375 #define final_printf debug_printf
376 
377 #ifdef __U_BOOT__
378 static void syntax_err(void) {
379 	 printf("syntax error\n");
380 }
381 #else
382 static void __syntax(char *file, int line) {
383 	error_msg("syntax error %s:%d", file, line);
384 }
385 #define syntax() __syntax(__FILE__, __LINE__)
386 #endif
387 
388 #ifdef __U_BOOT__
389 static void *xmalloc(size_t size);
390 static void *xrealloc(void *ptr, size_t size);
391 #else
392 /* Index of subroutines: */
393 /*   function prototypes for builtins */
394 static int builtin_cd(struct child_prog *child);
395 static int builtin_env(struct child_prog *child);
396 static int builtin_eval(struct child_prog *child);
397 static int builtin_exec(struct child_prog *child);
398 static int builtin_exit(struct child_prog *child);
399 static int builtin_export(struct child_prog *child);
400 static int builtin_fg_bg(struct child_prog *child);
401 static int builtin_help(struct child_prog *child);
402 static int builtin_jobs(struct child_prog *child);
403 static int builtin_pwd(struct child_prog *child);
404 static int builtin_read(struct child_prog *child);
405 static int builtin_set(struct child_prog *child);
406 static int builtin_shift(struct child_prog *child);
407 static int builtin_source(struct child_prog *child);
408 static int builtin_umask(struct child_prog *child);
409 static int builtin_unset(struct child_prog *child);
410 static int builtin_not_written(struct child_prog *child);
411 #endif
412 /*   o_string manipulation: */
413 static int b_check_space(o_string *o, int len);
414 static int b_addchr(o_string *o, int ch);
415 static void b_reset(o_string *o);
416 static int b_addqchr(o_string *o, int ch, int quote);
417 #ifndef __U_BOOT__
418 static int b_adduint(o_string *o, unsigned int i);
419 #endif
420 /*  in_str manipulations: */
421 static int static_get(struct in_str *i);
422 static int static_peek(struct in_str *i);
423 static int file_get(struct in_str *i);
424 static int file_peek(struct in_str *i);
425 #ifndef __U_BOOT__
426 static void setup_file_in_str(struct in_str *i, FILE *f);
427 #else
428 static void setup_file_in_str(struct in_str *i);
429 #endif
430 static void setup_string_in_str(struct in_str *i, const char *s);
431 #ifndef __U_BOOT__
432 /*  close_me manipulations: */
433 static void mark_open(int fd);
434 static void mark_closed(int fd);
435 static void close_all(void);
436 #endif
437 /*  "run" the final data structures: */
438 static char *indenter(int i);
439 static int free_pipe_list(struct pipe *head, int indent);
440 static int free_pipe(struct pipe *pi, int indent);
441 /*  really run the final data structures: */
442 #ifndef __U_BOOT__
443 static int setup_redirects(struct child_prog *prog, int squirrel[]);
444 #endif
445 static int run_list_real(struct pipe *pi);
446 #ifndef __U_BOOT__
447 static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
448 #endif
449 static int run_pipe_real(struct pipe *pi);
450 /*   extended glob support: */
451 #ifndef __U_BOOT__
452 static int globhack(const char *src, int flags, glob_t *pglob);
453 static int glob_needed(const char *s);
454 static int xglob(o_string *dest, int flags, glob_t *pglob);
455 #endif
456 /*   variable assignment: */
457 static int is_assignment(const char *s);
458 /*   data structure manipulation: */
459 #ifndef __U_BOOT__
460 static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
461 #endif
462 static void initialize_context(struct p_context *ctx);
463 static int done_word(o_string *dest, struct p_context *ctx);
464 static int done_command(struct p_context *ctx);
465 static int done_pipe(struct p_context *ctx, pipe_style type);
466 /*   primary string parsing: */
467 #ifndef __U_BOOT__
468 static int redirect_dup_num(struct in_str *input);
469 static int redirect_opt_num(o_string *o);
470 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
471 static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
472 #endif
473 static char *lookup_param(char *src);
474 static char *make_string(char **inp, int *nonnull);
475 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
476 #ifndef __U_BOOT__
477 static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
478 #endif
479 static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
480 /*   setup: */
481 static int parse_stream_outer(struct in_str *inp, int flag);
482 #ifndef __U_BOOT__
483 static int parse_string_outer(const char *s, int flag);
484 static int parse_file_outer(FILE *f);
485 #endif
486 #ifndef __U_BOOT__
487 /*   job management: */
488 static int checkjobs(struct pipe* fg_pipe);
489 static void insert_bg_job(struct pipe *pi);
490 static void remove_bg_job(struct pipe *pi);
491 #endif
492 /*     local variable support */
493 static char **make_list_in(char **inp, char *name);
494 static char *insert_var_value(char *inp);
495 static char *insert_var_value_sub(char *inp, int tag_subst);
496 
497 #ifndef __U_BOOT__
498 /* Table of built-in functions.  They can be forked or not, depending on
499  * context: within pipes, they fork.  As simple commands, they do not.
500  * When used in non-forking context, they can change global variables
501  * in the parent shell process.  If forked, of course they can not.
502  * For example, 'unset foo | whatever' will parse and run, but foo will
503  * still be set at the end. */
504 static struct built_in_command bltins[] = {
505 	{"bg", "Resume a job in the background", builtin_fg_bg},
506 	{"break", "Exit for, while or until loop", builtin_not_written},
507 	{"cd", "Change working directory", builtin_cd},
508 	{"continue", "Continue for, while or until loop", builtin_not_written},
509 	{"env", "Print all environment variables", builtin_env},
510 	{"eval", "Construct and run shell command", builtin_eval},
511 	{"exec", "Exec command, replacing this shell with the exec'd process",
512 		builtin_exec},
513 	{"exit", "Exit from shell()", builtin_exit},
514 	{"export", "Set environment variable", builtin_export},
515 	{"fg", "Bring job into the foreground", builtin_fg_bg},
516 	{"jobs", "Lists the active jobs", builtin_jobs},
517 	{"pwd", "Print current directory", builtin_pwd},
518 	{"read", "Input environment variable", builtin_read},
519 	{"return", "Return from a function", builtin_not_written},
520 	{"set", "Set/unset shell local variables", builtin_set},
521 	{"shift", "Shift positional parameters", builtin_shift},
522 	{"trap", "Trap signals", builtin_not_written},
523 	{"ulimit","Controls resource limits", builtin_not_written},
524 	{"umask","Sets file creation mask", builtin_umask},
525 	{"unset", "Unset environment variable", builtin_unset},
526 	{".", "Source-in and run commands in a file", builtin_source},
527 	{"help", "List shell built-in commands", builtin_help},
528 	{NULL, NULL, NULL}
529 };
530 
531 static const char *set_cwd(void)
532 {
533 	if(cwd==unknown)
534 		cwd = NULL;     /* xgetcwd(arg) called free(arg) */
535 	cwd = xgetcwd((char *)cwd);
536 	if (!cwd)
537 		cwd = unknown;
538 	return cwd;
539 }
540 
541 /* built-in 'eval' handler */
542 static int builtin_eval(struct child_prog *child)
543 {
544 	char *str = NULL;
545 	int rcode = EXIT_SUCCESS;
546 
547 	if (child->argv[1]) {
548 		str = make_string(child->argv + 1);
549 		parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
550 					FLAG_PARSE_SEMICOLON);
551 		free(str);
552 		rcode = last_return_code;
553 	}
554 	return rcode;
555 }
556 
557 /* built-in 'cd <path>' handler */
558 static int builtin_cd(struct child_prog *child)
559 {
560 	char *newdir;
561 	if (child->argv[1] == NULL)
562 		newdir = getenv("HOME");
563 	else
564 		newdir = child->argv[1];
565 	if (chdir(newdir)) {
566 		printf("cd: %s: %s\n", newdir, strerror(errno));
567 		return EXIT_FAILURE;
568 	}
569 	set_cwd();
570 	return EXIT_SUCCESS;
571 }
572 
573 /* built-in 'env' handler */
574 static int builtin_env(struct child_prog *dummy)
575 {
576 	char **e = environ;
577 	if (e == NULL) return EXIT_FAILURE;
578 	for (; *e; e++) {
579 		puts(*e);
580 	}
581 	return EXIT_SUCCESS;
582 }
583 
584 /* built-in 'exec' handler */
585 static int builtin_exec(struct child_prog *child)
586 {
587 	if (child->argv[1] == NULL)
588 		return EXIT_SUCCESS;   /* Really? */
589 	child->argv++;
590 	pseudo_exec(child);
591 	/* never returns */
592 }
593 
594 /* built-in 'exit' handler */
595 static int builtin_exit(struct child_prog *child)
596 {
597 	if (child->argv[1] == NULL)
598 		exit(last_return_code);
599 	exit (atoi(child->argv[1]));
600 }
601 
602 /* built-in 'export VAR=value' handler */
603 static int builtin_export(struct child_prog *child)
604 {
605 	int res = 0;
606 	char *name = child->argv[1];
607 
608 	if (name == NULL) {
609 		return (builtin_env(child));
610 	}
611 
612 	name = strdup(name);
613 
614 	if(name) {
615 		char *value = strchr(name, '=');
616 
617 		if (!value) {
618 			char *tmp;
619 			/* They are exporting something without an =VALUE */
620 
621 			value = get_local_var(name);
622 			if (value) {
623 				size_t ln = strlen(name);
624 
625 				tmp = realloc(name, ln+strlen(value)+2);
626 				if(tmp==NULL)
627 					res = -1;
628 				else {
629 					sprintf(tmp+ln, "=%s", value);
630 					name = tmp;
631 				}
632 			} else {
633 				/* bash does not return an error when trying to export
634 				 * an undefined variable.  Do likewise. */
635 				res = 1;
636 			}
637 		}
638 	}
639 	if (res<0)
640 		perror_msg("export");
641 	else if(res==0)
642 		res = set_local_var(name, 1);
643 	else
644 		res = 0;
645 	free(name);
646 	return res;
647 }
648 
649 /* built-in 'fg' and 'bg' handler */
650 static int builtin_fg_bg(struct child_prog *child)
651 {
652 	int i, jobnum;
653 	struct pipe *pi=NULL;
654 
655 	if (!interactive)
656 		return EXIT_FAILURE;
657 	/* If they gave us no args, assume they want the last backgrounded task */
658 	if (!child->argv[1]) {
659 		for (pi = job_list; pi; pi = pi->next) {
660 			if (pi->jobid == last_jobid) {
661 				break;
662 			}
663 		}
664 		if (!pi) {
665 			error_msg("%s: no current job", child->argv[0]);
666 			return EXIT_FAILURE;
667 		}
668 	} else {
669 		if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
670 			error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
671 			return EXIT_FAILURE;
672 		}
673 		for (pi = job_list; pi; pi = pi->next) {
674 			if (pi->jobid == jobnum) {
675 				break;
676 			}
677 		}
678 		if (!pi) {
679 			error_msg("%s: %d: no such job", child->argv[0], jobnum);
680 			return EXIT_FAILURE;
681 		}
682 	}
683 
684 	if (*child->argv[0] == 'f') {
685 		/* Put the job into the foreground.  */
686 		tcsetpgrp(shell_terminal, pi->pgrp);
687 	}
688 
689 	/* Restart the processes in the job */
690 	for (i = 0; i < pi->num_progs; i++)
691 		pi->progs[i].is_stopped = 0;
692 
693 	if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) {
694 		if (i == ESRCH) {
695 			remove_bg_job(pi);
696 		} else {
697 			perror_msg("kill (SIGCONT)");
698 		}
699 	}
700 
701 	pi->stopped_progs = 0;
702 	return EXIT_SUCCESS;
703 }
704 
705 /* built-in 'help' handler */
706 static int builtin_help(struct child_prog *dummy)
707 {
708 	struct built_in_command *x;
709 
710 	printf("\nBuilt-in commands:\n");
711 	printf("-------------------\n");
712 	for (x = bltins; x->cmd; x++) {
713 		if (x->descr==NULL)
714 			continue;
715 		printf("%s\t%s\n", x->cmd, x->descr);
716 	}
717 	printf("\n\n");
718 	return EXIT_SUCCESS;
719 }
720 
721 /* built-in 'jobs' handler */
722 static int builtin_jobs(struct child_prog *child)
723 {
724 	struct pipe *job;
725 	char *status_string;
726 
727 	for (job = job_list; job; job = job->next) {
728 		if (job->running_progs == job->stopped_progs)
729 			status_string = "Stopped";
730 		else
731 			status_string = "Running";
732 
733 		printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
734 	}
735 	return EXIT_SUCCESS;
736 }
737 
738 
739 /* built-in 'pwd' handler */
740 static int builtin_pwd(struct child_prog *dummy)
741 {
742 	puts(set_cwd());
743 	return EXIT_SUCCESS;
744 }
745 
746 /* built-in 'read VAR' handler */
747 static int builtin_read(struct child_prog *child)
748 {
749 	int res;
750 
751 	if (child->argv[1]) {
752 		char string[BUFSIZ];
753 		char *var = 0;
754 
755 		string[0] = 0;  /* In case stdin has only EOF */
756 		/* read string */
757 		fgets(string, sizeof(string), stdin);
758 		chomp(string);
759 		var = malloc(strlen(child->argv[1])+strlen(string)+2);
760 		if(var) {
761 			sprintf(var, "%s=%s", child->argv[1], string);
762 			res = set_local_var(var, 0);
763 		} else
764 			res = -1;
765 		if (res)
766 			fprintf(stderr, "read: %m\n");
767 		free(var);      /* So not move up to avoid breaking errno */
768 		return res;
769 	} else {
770 		do res=getchar(); while(res!='\n' && res!=EOF);
771 		return 0;
772 	}
773 }
774 
775 /* built-in 'set VAR=value' handler */
776 static int builtin_set(struct child_prog *child)
777 {
778 	char *temp = child->argv[1];
779 	struct variables *e;
780 
781 	if (temp == NULL)
782 		for(e = top_vars; e; e=e->next)
783 			printf("%s=%s\n", e->name, e->value);
784 	else
785 		set_local_var(temp, 0);
786 
787 		return EXIT_SUCCESS;
788 }
789 
790 
791 /* Built-in 'shift' handler */
792 static int builtin_shift(struct child_prog *child)
793 {
794 	int n=1;
795 	if (child->argv[1]) {
796 		n=atoi(child->argv[1]);
797 	}
798 	if (n>=0 && n<global_argc) {
799 		/* XXX This probably breaks $0 */
800 		global_argc -= n;
801 		global_argv += n;
802 		return EXIT_SUCCESS;
803 	} else {
804 		return EXIT_FAILURE;
805 	}
806 }
807 
808 /* Built-in '.' handler (read-in and execute commands from file) */
809 static int builtin_source(struct child_prog *child)
810 {
811 	FILE *input;
812 	int status;
813 
814 	if (child->argv[1] == NULL)
815 		return EXIT_FAILURE;
816 
817 	/* XXX search through $PATH is missing */
818 	input = fopen(child->argv[1], "r");
819 	if (!input) {
820 		error_msg("Couldn't open file '%s'", child->argv[1]);
821 		return EXIT_FAILURE;
822 	}
823 
824 	/* Now run the file */
825 	/* XXX argv and argc are broken; need to save old global_argv
826 	 * (pointer only is OK!) on this stack frame,
827 	 * set global_argv=child->argv+1, recurse, and restore. */
828 	mark_open(fileno(input));
829 	status = parse_file_outer(input);
830 	mark_closed(fileno(input));
831 	fclose(input);
832 	return (status);
833 }
834 
835 static int builtin_umask(struct child_prog *child)
836 {
837 	mode_t new_umask;
838 	const char *arg = child->argv[1];
839 	char *end;
840 	if (arg) {
841 		new_umask=strtoul(arg, &end, 8);
842 		if (*end!='\0' || end == arg) {
843 			return EXIT_FAILURE;
844 		}
845 	} else {
846 		printf("%.3o\n", (unsigned int) (new_umask=umask(0)));
847 	}
848 	umask(new_umask);
849 	return EXIT_SUCCESS;
850 }
851 
852 /* built-in 'unset VAR' handler */
853 static int builtin_unset(struct child_prog *child)
854 {
855 	/* bash returned already true */
856 	unset_local_var(child->argv[1]);
857 	return EXIT_SUCCESS;
858 }
859 
860 static int builtin_not_written(struct child_prog *child)
861 {
862 	printf("builtin_%s not written\n",child->argv[0]);
863 	return EXIT_FAILURE;
864 }
865 #endif
866 
867 static int b_check_space(o_string *o, int len)
868 {
869 	/* It would be easy to drop a more restrictive policy
870 	 * in here, such as setting a maximum string length */
871 	if (o->length + len > o->maxlen) {
872 		char *old_data = o->data;
873 		/* assert (data == NULL || o->maxlen != 0); */
874 		o->maxlen += max(2*len, B_CHUNK);
875 		o->data = realloc(o->data, 1 + o->maxlen);
876 		if (o->data == NULL) {
877 			free(old_data);
878 		}
879 	}
880 	return o->data == NULL;
881 }
882 
883 static int b_addchr(o_string *o, int ch)
884 {
885 	debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
886 	if (b_check_space(o, 1)) return B_NOSPAC;
887 	o->data[o->length] = ch;
888 	o->length++;
889 	o->data[o->length] = '\0';
890 	return 0;
891 }
892 
893 static void b_reset(o_string *o)
894 {
895 	o->length = 0;
896 	o->nonnull = 0;
897 	if (o->data != NULL) *o->data = '\0';
898 }
899 
900 static void b_free(o_string *o)
901 {
902 	b_reset(o);
903 	free(o->data);
904 	o->data = NULL;
905 	o->maxlen = 0;
906 }
907 
908 /* My analysis of quoting semantics tells me that state information
909  * is associated with a destination, not a source.
910  */
911 static int b_addqchr(o_string *o, int ch, int quote)
912 {
913 	if (quote && strchr("*?[\\",ch)) {
914 		int rc;
915 		rc = b_addchr(o, '\\');
916 		if (rc) return rc;
917 	}
918 	return b_addchr(o, ch);
919 }
920 
921 #ifndef __U_BOOT__
922 static int b_adduint(o_string *o, unsigned int i)
923 {
924 	int r;
925 	char *p = simple_itoa(i);
926 	/* no escape checking necessary */
927 	do r=b_addchr(o, *p++); while (r==0 && *p);
928 	return r;
929 }
930 #endif
931 
932 static int static_get(struct in_str *i)
933 {
934 	int ch = *i->p++;
935 	if (ch=='\0') return EOF;
936 	return ch;
937 }
938 
939 static int static_peek(struct in_str *i)
940 {
941 	return *i->p;
942 }
943 
944 #ifndef __U_BOOT__
945 static inline void cmdedit_set_initial_prompt(void)
946 {
947 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
948 	PS1 = NULL;
949 #else
950 	PS1 = getenv("PS1");
951 	if(PS1==0)
952 		PS1 = "\\w \\$ ";
953 #endif
954 }
955 
956 static inline void setup_prompt_string(int promptmode, char **prompt_str)
957 {
958 	debug_printf("setup_prompt_string %d ",promptmode);
959 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
960 	/* Set up the prompt */
961 	if (promptmode == 1) {
962 		free(PS1);
963 		PS1=xmalloc(strlen(cwd)+4);
964 		sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ?  "$ ":"# ");
965 		*prompt_str = PS1;
966 	} else {
967 		*prompt_str = PS2;
968 	}
969 #else
970 	*prompt_str = (promptmode==1)? PS1 : PS2;
971 #endif
972 	debug_printf("result %s\n",*prompt_str);
973 }
974 #endif
975 
976 static void get_user_input(struct in_str *i)
977 {
978 #ifndef __U_BOOT__
979 	char *prompt_str;
980 	static char the_command[BUFSIZ];
981 
982 	setup_prompt_string(i->promptmode, &prompt_str);
983 #ifdef CONFIG_FEATURE_COMMAND_EDITING
984 	/*
985 	 ** enable command line editing only while a command line
986 	 ** is actually being read; otherwise, we'll end up bequeathing
987 	 ** atexit() handlers and other unwanted stuff to our
988 	 ** child processes (rob@sysgo.de)
989 	 */
990 	cmdedit_read_input(prompt_str, the_command);
991 #else
992 	fputs(prompt_str, stdout);
993 	fflush(stdout);
994 	the_command[0]=fgetc(i->file);
995 	the_command[1]='\0';
996 #endif
997 	fflush(stdout);
998 	i->p = the_command;
999 #else
1000 	int n;
1001 	static char the_command[CONFIG_SYS_CBSIZE + 1];
1002 
1003 	bootretry_reset_cmd_timeout();
1004 	i->__promptme = 1;
1005 	if (i->promptmode == 1) {
1006 		n = cli_readline(CONFIG_SYS_PROMPT);
1007 	} else {
1008 		n = cli_readline(CONFIG_SYS_PROMPT_HUSH_PS2);
1009 	}
1010 #ifdef CONFIG_BOOT_RETRY_TIME
1011 	if (n == -2) {
1012 	  puts("\nTimeout waiting for command\n");
1013 #  ifdef CONFIG_RESET_TO_RETRY
1014 	  do_reset(NULL, 0, 0, NULL);
1015 #  else
1016 #	error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1017 #  endif
1018 	}
1019 #endif
1020 	if (n == -1 ) {
1021 		flag_repeat = 0;
1022 		i->__promptme = 0;
1023 	}
1024 	n = strlen(console_buffer);
1025 	console_buffer[n] = '\n';
1026 	console_buffer[n+1]= '\0';
1027 	if (had_ctrlc()) flag_repeat = 0;
1028 	clear_ctrlc();
1029 	do_repeat = 0;
1030 	if (i->promptmode == 1) {
1031 		if (console_buffer[0] == '\n'&& flag_repeat == 0) {
1032 			strcpy(the_command,console_buffer);
1033 		}
1034 		else {
1035 			if (console_buffer[0] != '\n') {
1036 				strcpy(the_command,console_buffer);
1037 				flag_repeat = 1;
1038 			}
1039 			else {
1040 				do_repeat = 1;
1041 			}
1042 		}
1043 		i->p = the_command;
1044 	}
1045 	else {
1046 		if (console_buffer[0] != '\n') {
1047 			if (strlen(the_command) + strlen(console_buffer)
1048 			    < CONFIG_SYS_CBSIZE) {
1049 				n = strlen(the_command);
1050 				the_command[n-1] = ' ';
1051 				strcpy(&the_command[n],console_buffer);
1052 			}
1053 			else {
1054 				the_command[0] = '\n';
1055 				the_command[1] = '\0';
1056 				flag_repeat = 0;
1057 			}
1058 		}
1059 		if (i->__promptme == 0) {
1060 			the_command[0] = '\n';
1061 			the_command[1] = '\0';
1062 		}
1063 		i->p = console_buffer;
1064 	}
1065 #endif
1066 }
1067 
1068 /* This is the magic location that prints prompts
1069  * and gets data back from the user */
1070 static int file_get(struct in_str *i)
1071 {
1072 	int ch;
1073 
1074 	ch = 0;
1075 	/* If there is data waiting, eat it up */
1076 	if (i->p && *i->p) {
1077 		ch = *i->p++;
1078 	} else {
1079 		/* need to double check i->file because we might be doing something
1080 		 * more complicated by now, like sourcing or substituting. */
1081 #ifndef __U_BOOT__
1082 		if (i->__promptme && interactive && i->file == stdin) {
1083 			while(! i->p || (interactive && strlen(i->p)==0) ) {
1084 #else
1085 			while(! i->p  || strlen(i->p)==0 ) {
1086 #endif
1087 				get_user_input(i);
1088 			}
1089 			i->promptmode=2;
1090 #ifndef __U_BOOT__
1091 			i->__promptme = 0;
1092 #endif
1093 			if (i->p && *i->p) {
1094 				ch = *i->p++;
1095 			}
1096 #ifndef __U_BOOT__
1097 		} else {
1098 			ch = fgetc(i->file);
1099 		}
1100 
1101 #endif
1102 		debug_printf("b_getch: got a %d\n", ch);
1103 	}
1104 #ifndef __U_BOOT__
1105 	if (ch == '\n') i->__promptme=1;
1106 #endif
1107 	return ch;
1108 }
1109 
1110 /* All the callers guarantee this routine will never be
1111  * used right after a newline, so prompting is not needed.
1112  */
1113 static int file_peek(struct in_str *i)
1114 {
1115 #ifndef __U_BOOT__
1116 	if (i->p && *i->p) {
1117 #endif
1118 		return *i->p;
1119 #ifndef __U_BOOT__
1120 	} else {
1121 		i->peek_buf[0] = fgetc(i->file);
1122 		i->peek_buf[1] = '\0';
1123 		i->p = i->peek_buf;
1124 		debug_printf("b_peek: got a %d\n", *i->p);
1125 		return *i->p;
1126 	}
1127 #endif
1128 }
1129 
1130 #ifndef __U_BOOT__
1131 static void setup_file_in_str(struct in_str *i, FILE *f)
1132 #else
1133 static void setup_file_in_str(struct in_str *i)
1134 #endif
1135 {
1136 	i->peek = file_peek;
1137 	i->get = file_get;
1138 	i->__promptme=1;
1139 	i->promptmode=1;
1140 #ifndef __U_BOOT__
1141 	i->file = f;
1142 #endif
1143 	i->p = NULL;
1144 }
1145 
1146 static void setup_string_in_str(struct in_str *i, const char *s)
1147 {
1148 	i->peek = static_peek;
1149 	i->get = static_get;
1150 	i->__promptme=1;
1151 	i->promptmode=1;
1152 	i->p = s;
1153 }
1154 
1155 #ifndef __U_BOOT__
1156 static void mark_open(int fd)
1157 {
1158 	struct close_me *new = xmalloc(sizeof(struct close_me));
1159 	new->fd = fd;
1160 	new->next = close_me_head;
1161 	close_me_head = new;
1162 }
1163 
1164 static void mark_closed(int fd)
1165 {
1166 	struct close_me *tmp;
1167 	if (close_me_head == NULL || close_me_head->fd != fd)
1168 		error_msg_and_die("corrupt close_me");
1169 	tmp = close_me_head;
1170 	close_me_head = close_me_head->next;
1171 	free(tmp);
1172 }
1173 
1174 static void close_all(void)
1175 {
1176 	struct close_me *c;
1177 	for (c=close_me_head; c; c=c->next) {
1178 		close(c->fd);
1179 	}
1180 	close_me_head = NULL;
1181 }
1182 
1183 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1184  * and stderr if they are redirected. */
1185 static int setup_redirects(struct child_prog *prog, int squirrel[])
1186 {
1187 	int openfd, mode;
1188 	struct redir_struct *redir;
1189 
1190 	for (redir=prog->redirects; redir; redir=redir->next) {
1191 		if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1192 			/* something went wrong in the parse.  Pretend it didn't happen */
1193 			continue;
1194 		}
1195 		if (redir->dup == -1) {
1196 			mode=redir_table[redir->type].mode;
1197 			openfd = open(redir->word.gl_pathv[0], mode, 0666);
1198 			if (openfd < 0) {
1199 			/* this could get lost if stderr has been redirected, but
1200 			   bash and ash both lose it as well (though zsh doesn't!) */
1201 				perror_msg("error opening %s", redir->word.gl_pathv[0]);
1202 				return 1;
1203 			}
1204 		} else {
1205 			openfd = redir->dup;
1206 		}
1207 
1208 		if (openfd != redir->fd) {
1209 			if (squirrel && redir->fd < 3) {
1210 				squirrel[redir->fd] = dup(redir->fd);
1211 			}
1212 			if (openfd == -3) {
1213 				close(openfd);
1214 			} else {
1215 				dup2(openfd, redir->fd);
1216 				if (redir->dup == -1)
1217 					close (openfd);
1218 			}
1219 		}
1220 	}
1221 	return 0;
1222 }
1223 
1224 static void restore_redirects(int squirrel[])
1225 {
1226 	int i, fd;
1227 	for (i=0; i<3; i++) {
1228 		fd = squirrel[i];
1229 		if (fd != -1) {
1230 			/* No error checking.  I sure wouldn't know what
1231 			 * to do with an error if I found one! */
1232 			dup2(fd, i);
1233 			close(fd);
1234 		}
1235 	}
1236 }
1237 
1238 /* never returns */
1239 /* XXX no exit() here.  If you don't exec, use _exit instead.
1240  * The at_exit handlers apparently confuse the calling process,
1241  * in particular stdin handling.  Not sure why? */
1242 static void pseudo_exec(struct child_prog *child)
1243 {
1244 	int i, rcode;
1245 	char *p;
1246 	struct built_in_command *x;
1247 	if (child->argv) {
1248 		for (i=0; is_assignment(child->argv[i]); i++) {
1249 			debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
1250 			p = insert_var_value(child->argv[i]);
1251 			putenv(strdup(p));
1252 			if (p != child->argv[i]) free(p);
1253 		}
1254 		child->argv+=i;  /* XXX this hack isn't so horrible, since we are about
1255 					to exit, and therefore don't need to keep data
1256 					structures consistent for free() use. */
1257 		/* If a variable is assigned in a forest, and nobody listens,
1258 		 * was it ever really set?
1259 		 */
1260 		if (child->argv[0] == NULL) {
1261 			_exit(EXIT_SUCCESS);
1262 		}
1263 
1264 		/*
1265 		 * Check if the command matches any of the builtins.
1266 		 * Depending on context, this might be redundant.  But it's
1267 		 * easier to waste a few CPU cycles than it is to figure out
1268 		 * if this is one of those cases.
1269 		 */
1270 		for (x = bltins; x->cmd; x++) {
1271 			if (strcmp(child->argv[0], x->cmd) == 0 ) {
1272 				debug_printf("builtin exec %s\n", child->argv[0]);
1273 				rcode = x->function(child);
1274 				fflush(stdout);
1275 				_exit(rcode);
1276 			}
1277 		}
1278 
1279 		/* Check if the command matches any busybox internal commands
1280 		 * ("applets") here.
1281 		 * FIXME: This feature is not 100% safe, since
1282 		 * BusyBox is not fully reentrant, so we have no guarantee the things
1283 		 * from the .bss are still zeroed, or that things from .data are still
1284 		 * at their defaults.  We could exec ourself from /proc/self/exe, but I
1285 		 * really dislike relying on /proc for things.  We could exec ourself
1286 		 * from global_argv[0], but if we are in a chroot, we may not be able
1287 		 * to find ourself... */
1288 #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1289 		{
1290 			int argc_l;
1291 			char** argv_l=child->argv;
1292 			char *name = child->argv[0];
1293 
1294 #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
1295 			/* Following discussions from November 2000 on the busybox mailing
1296 			 * list, the default configuration, (without
1297 			 * get_last_path_component()) lets the user force use of an
1298 			 * external command by specifying the full (with slashes) filename.
1299 			 * If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN then applets
1300 			 * _aways_ override external commands, so if you want to run
1301 			 * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the
1302 			 * filesystem and is _not_ busybox.  Some systems may want this,
1303 			 * most do not.  */
1304 			name = get_last_path_component(name);
1305 #endif
1306 			/* Count argc for use in a second... */
1307 			for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
1308 			optind = 1;
1309 			debug_printf("running applet %s\n", name);
1310 			run_applet_by_name(name, argc_l, child->argv);
1311 		}
1312 #endif
1313 		debug_printf("exec of %s\n",child->argv[0]);
1314 		execvp(child->argv[0],child->argv);
1315 		perror_msg("couldn't exec: %s",child->argv[0]);
1316 		_exit(1);
1317 	} else if (child->group) {
1318 		debug_printf("runtime nesting to group\n");
1319 		interactive=0;    /* crucial!!!! */
1320 		rcode = run_list_real(child->group);
1321 		/* OK to leak memory by not calling free_pipe_list,
1322 		 * since this process is about to exit */
1323 		_exit(rcode);
1324 	} else {
1325 		/* Can happen.  See what bash does with ">foo" by itself. */
1326 		debug_printf("trying to pseudo_exec null command\n");
1327 		_exit(EXIT_SUCCESS);
1328 	}
1329 }
1330 
1331 static void insert_bg_job(struct pipe *pi)
1332 {
1333 	struct pipe *thejob;
1334 
1335 	/* Linear search for the ID of the job to use */
1336 	pi->jobid = 1;
1337 	for (thejob = job_list; thejob; thejob = thejob->next)
1338 		if (thejob->jobid >= pi->jobid)
1339 			pi->jobid = thejob->jobid + 1;
1340 
1341 	/* add thejob to the list of running jobs */
1342 	if (!job_list) {
1343 		thejob = job_list = xmalloc(sizeof(*thejob));
1344 	} else {
1345 		for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
1346 		thejob->next = xmalloc(sizeof(*thejob));
1347 		thejob = thejob->next;
1348 	}
1349 
1350 	/* physically copy the struct job */
1351 	memcpy(thejob, pi, sizeof(struct pipe));
1352 	thejob->next = NULL;
1353 	thejob->running_progs = thejob->num_progs;
1354 	thejob->stopped_progs = 0;
1355 	thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1356 
1357 	/*if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) */
1358 	{
1359 		char *bar=thejob->text;
1360 		char **foo=pi->progs[0].argv;
1361 		while(foo && *foo) {
1362 			bar += sprintf(bar, "%s ", *foo++);
1363 		}
1364 	}
1365 
1366 	/* we don't wait for background thejobs to return -- append it
1367 	   to the list of backgrounded thejobs and leave it alone */
1368 	printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1369 	last_bg_pid = thejob->progs[0].pid;
1370 	last_jobid = thejob->jobid;
1371 }
1372 
1373 /* remove a backgrounded job */
1374 static void remove_bg_job(struct pipe *pi)
1375 {
1376 	struct pipe *prev_pipe;
1377 
1378 	if (pi == job_list) {
1379 		job_list = pi->next;
1380 	} else {
1381 		prev_pipe = job_list;
1382 		while (prev_pipe->next != pi)
1383 			prev_pipe = prev_pipe->next;
1384 		prev_pipe->next = pi->next;
1385 	}
1386 	if (job_list)
1387 		last_jobid = job_list->jobid;
1388 	else
1389 		last_jobid = 0;
1390 
1391 	pi->stopped_progs = 0;
1392 	free_pipe(pi, 0);
1393 	free(pi);
1394 }
1395 
1396 /* Checks to see if any processes have exited -- if they
1397    have, figure out why and see if a job has completed */
1398 static int checkjobs(struct pipe* fg_pipe)
1399 {
1400 	int attributes;
1401 	int status;
1402 	int prognum = 0;
1403 	struct pipe *pi;
1404 	pid_t childpid;
1405 
1406 	attributes = WUNTRACED;
1407 	if (fg_pipe==NULL) {
1408 		attributes |= WNOHANG;
1409 	}
1410 
1411 	while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1412 		if (fg_pipe) {
1413 			int i, rcode = 0;
1414 			for (i=0; i < fg_pipe->num_progs; i++) {
1415 				if (fg_pipe->progs[i].pid == childpid) {
1416 					if (i==fg_pipe->num_progs-1)
1417 						rcode=WEXITSTATUS(status);
1418 					(fg_pipe->num_progs)--;
1419 					return(rcode);
1420 				}
1421 			}
1422 		}
1423 
1424 		for (pi = job_list; pi; pi = pi->next) {
1425 			prognum = 0;
1426 			while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1427 				prognum++;
1428 			}
1429 			if (prognum < pi->num_progs)
1430 				break;
1431 		}
1432 
1433 		if(pi==NULL) {
1434 			debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
1435 			continue;
1436 		}
1437 
1438 		if (WIFEXITED(status) || WIFSIGNALED(status)) {
1439 			/* child exited */
1440 			pi->running_progs--;
1441 			pi->progs[prognum].pid = 0;
1442 
1443 			if (!pi->running_progs) {
1444 				printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
1445 				remove_bg_job(pi);
1446 			}
1447 		} else {
1448 			/* child stopped */
1449 			pi->stopped_progs++;
1450 			pi->progs[prognum].is_stopped = 1;
1451 
1452 #if 0
1453 			/* Printing this stuff is a pain, since it tends to
1454 			 * overwrite the prompt an inconveinient moments.  So
1455 			 * don't do that.  */
1456 			if (pi->stopped_progs == pi->num_progs) {
1457 				printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
1458 			}
1459 #endif
1460 		}
1461 	}
1462 
1463 	if (childpid == -1 && errno != ECHILD)
1464 		perror_msg("waitpid");
1465 
1466 	/* move the shell to the foreground */
1467 	/*if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) */
1468 	/*	perror_msg("tcsetpgrp-2"); */
1469 	return -1;
1470 }
1471 
1472 /* Figure out our controlling tty, checking in order stderr,
1473  * stdin, and stdout.  If check_pgrp is set, also check that
1474  * we belong to the foreground process group associated with
1475  * that tty.  The value of shell_terminal is needed in order to call
1476  * tcsetpgrp(shell_terminal, ...); */
1477 void controlling_tty(int check_pgrp)
1478 {
1479 	pid_t curpgrp;
1480 
1481 	if ((curpgrp = tcgetpgrp(shell_terminal = 2)) < 0
1482 			&& (curpgrp = tcgetpgrp(shell_terminal = 0)) < 0
1483 			&& (curpgrp = tcgetpgrp(shell_terminal = 1)) < 0)
1484 		goto shell_terminal_error;
1485 
1486 	if (check_pgrp && curpgrp != getpgid(0))
1487 		goto shell_terminal_error;
1488 
1489 	return;
1490 
1491 shell_terminal_error:
1492 		shell_terminal = -1;
1493 		return;
1494 }
1495 #endif
1496 
1497 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1498  * to finish.  See checkjobs().
1499  *
1500  * return code is normally -1, when the caller has to wait for children
1501  * to finish to determine the exit status of the pipe.  If the pipe
1502  * is a simple builtin command, however, the action is done by the
1503  * time run_pipe_real returns, and the exit code is provided as the
1504  * return value.
1505  *
1506  * The input of the pipe is always stdin, the output is always
1507  * stdout.  The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1508  * because it tries to avoid running the command substitution in
1509  * subshell, when that is in fact necessary.  The subshell process
1510  * now has its stdout directed to the input of the appropriate pipe,
1511  * so this routine is noticeably simpler.
1512  */
1513 static int run_pipe_real(struct pipe *pi)
1514 {
1515 	int i;
1516 #ifndef __U_BOOT__
1517 	int nextin, nextout;
1518 	int pipefds[2];				/* pipefds[0] is for reading */
1519 	struct child_prog *child;
1520 	struct built_in_command *x;
1521 	char *p;
1522 # if __GNUC__
1523 	/* Avoid longjmp clobbering */
1524 	(void) &i;
1525 	(void) &nextin;
1526 	(void) &nextout;
1527 	(void) &child;
1528 # endif
1529 #else
1530 	int nextin;
1531 	int flag = do_repeat ? CMD_FLAG_REPEAT : 0;
1532 	struct child_prog *child;
1533 	char *p;
1534 # if __GNUC__
1535 	/* Avoid longjmp clobbering */
1536 	(void) &i;
1537 	(void) &nextin;
1538 	(void) &child;
1539 # endif
1540 #endif	/* __U_BOOT__ */
1541 
1542 	nextin = 0;
1543 #ifndef __U_BOOT__
1544 	pi->pgrp = -1;
1545 #endif
1546 
1547 	/* Check if this is a simple builtin (not part of a pipe).
1548 	 * Builtins within pipes have to fork anyway, and are handled in
1549 	 * pseudo_exec.  "echo foo | read bar" doesn't work on bash, either.
1550 	 */
1551 	if (pi->num_progs == 1) child = & (pi->progs[0]);
1552 #ifndef __U_BOOT__
1553 	if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1554 		int squirrel[] = {-1, -1, -1};
1555 		int rcode;
1556 		debug_printf("non-subshell grouping\n");
1557 		setup_redirects(child, squirrel);
1558 		/* XXX could we merge code with following builtin case,
1559 		 * by creating a pseudo builtin that calls run_list_real? */
1560 		rcode = run_list_real(child->group);
1561 		restore_redirects(squirrel);
1562 #else
1563 		if (pi->num_progs == 1 && child->group) {
1564 		int rcode;
1565 		debug_printf("non-subshell grouping\n");
1566 		rcode = run_list_real(child->group);
1567 #endif
1568 		return rcode;
1569 	} else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1570 		for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
1571 		if (i!=0 && child->argv[i]==NULL) {
1572 			/* assignments, but no command: set the local environment */
1573 			for (i=0; child->argv[i]!=NULL; i++) {
1574 
1575 				/* Ok, this case is tricky.  We have to decide if this is a
1576 				 * local variable, or an already exported variable.  If it is
1577 				 * already exported, we have to export the new value.  If it is
1578 				 * not exported, we need only set this as a local variable.
1579 				 * This junk is all to decide whether or not to export this
1580 				 * variable. */
1581 				int export_me=0;
1582 				char *name, *value;
1583 				name = xstrdup(child->argv[i]);
1584 				debug_printf("Local environment set: %s\n", name);
1585 				value = strchr(name, '=');
1586 				if (value)
1587 					*value=0;
1588 #ifndef __U_BOOT__
1589 				if ( get_local_var(name)) {
1590 					export_me=1;
1591 				}
1592 #endif
1593 				free(name);
1594 				p = insert_var_value(child->argv[i]);
1595 				set_local_var(p, export_me);
1596 				if (p != child->argv[i]) free(p);
1597 			}
1598 			return EXIT_SUCCESS;   /* don't worry about errors in set_local_var() yet */
1599 		}
1600 		for (i = 0; is_assignment(child->argv[i]); i++) {
1601 			p = insert_var_value(child->argv[i]);
1602 #ifndef __U_BOOT__
1603 			putenv(strdup(p));
1604 #else
1605 			set_local_var(p, 0);
1606 #endif
1607 			if (p != child->argv[i]) {
1608 				child->sp--;
1609 				free(p);
1610 			}
1611 		}
1612 		if (child->sp) {
1613 			char * str = NULL;
1614 
1615 			str = make_string(child->argv + i,
1616 					  child->argv_nonnull + i);
1617 			parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1618 			free(str);
1619 			return last_return_code;
1620 		}
1621 #ifndef __U_BOOT__
1622 		for (x = bltins; x->cmd; x++) {
1623 			if (strcmp(child->argv[i], x->cmd) == 0 ) {
1624 				int squirrel[] = {-1, -1, -1};
1625 				int rcode;
1626 				if (x->function == builtin_exec && child->argv[i+1]==NULL) {
1627 					debug_printf("magic exec\n");
1628 					setup_redirects(child,NULL);
1629 					return EXIT_SUCCESS;
1630 				}
1631 				debug_printf("builtin inline %s\n", child->argv[0]);
1632 				/* XXX setup_redirects acts on file descriptors, not FILEs.
1633 				 * This is perfect for work that comes after exec().
1634 				 * Is it really safe for inline use?  Experimentally,
1635 				 * things seem to work with glibc. */
1636 				setup_redirects(child, squirrel);
1637 
1638 				child->argv += i;  /* XXX horrible hack */
1639 				rcode = x->function(child);
1640 				/* XXX restore hack so free() can work right */
1641 				child->argv -= i;
1642 				restore_redirects(squirrel);
1643 			}
1644 			return rcode;
1645 		}
1646 #else
1647 		/* check ";", because ,example , argv consist from
1648 		 * "help;flinfo" must not execute
1649 		 */
1650 		if (strchr(child->argv[i], ';')) {
1651 			printf("Unknown command '%s' - try 'help' or use "
1652 					"'run' command\n", child->argv[i]);
1653 			return -1;
1654 		}
1655 		/* Process the command */
1656 		return cmd_process(flag, child->argc, child->argv,
1657 				   &flag_repeat, NULL);
1658 #endif
1659 	}
1660 #ifndef __U_BOOT__
1661 
1662 	for (i = 0; i < pi->num_progs; i++) {
1663 		child = & (pi->progs[i]);
1664 
1665 		/* pipes are inserted between pairs of commands */
1666 		if ((i + 1) < pi->num_progs) {
1667 			if (pipe(pipefds)<0) perror_msg_and_die("pipe");
1668 			nextout = pipefds[1];
1669 		} else {
1670 			nextout=1;
1671 			pipefds[0] = -1;
1672 		}
1673 
1674 		/* XXX test for failed fork()? */
1675 		if (!(child->pid = fork())) {
1676 			/* Set the handling for job control signals back to the default.  */
1677 			signal(SIGINT, SIG_DFL);
1678 			signal(SIGQUIT, SIG_DFL);
1679 			signal(SIGTERM, SIG_DFL);
1680 			signal(SIGTSTP, SIG_DFL);
1681 			signal(SIGTTIN, SIG_DFL);
1682 			signal(SIGTTOU, SIG_DFL);
1683 			signal(SIGCHLD, SIG_DFL);
1684 
1685 			close_all();
1686 
1687 			if (nextin != 0) {
1688 				dup2(nextin, 0);
1689 				close(nextin);
1690 			}
1691 			if (nextout != 1) {
1692 				dup2(nextout, 1);
1693 				close(nextout);
1694 			}
1695 			if (pipefds[0]!=-1) {
1696 				close(pipefds[0]);  /* opposite end of our output pipe */
1697 			}
1698 
1699 			/* Like bash, explicit redirects override pipes,
1700 			 * and the pipe fd is available for dup'ing. */
1701 			setup_redirects(child,NULL);
1702 
1703 			if (interactive && pi->followup!=PIPE_BG) {
1704 				/* If we (the child) win the race, put ourselves in the process
1705 				 * group whose leader is the first process in this pipe. */
1706 				if (pi->pgrp < 0) {
1707 					pi->pgrp = getpid();
1708 				}
1709 				if (setpgid(0, pi->pgrp) == 0) {
1710 					tcsetpgrp(2, pi->pgrp);
1711 				}
1712 			}
1713 
1714 			pseudo_exec(child);
1715 		}
1716 
1717 
1718 		/* put our child in the process group whose leader is the
1719 		   first process in this pipe */
1720 		if (pi->pgrp < 0) {
1721 			pi->pgrp = child->pid;
1722 		}
1723 		/* Don't check for errors.  The child may be dead already,
1724 		 * in which case setpgid returns error code EACCES. */
1725 		setpgid(child->pid, pi->pgrp);
1726 
1727 		if (nextin != 0)
1728 			close(nextin);
1729 		if (nextout != 1)
1730 			close(nextout);
1731 
1732 		/* If there isn't another process, nextin is garbage
1733 		   but it doesn't matter */
1734 		nextin = pipefds[0];
1735 	}
1736 #endif
1737 	return -1;
1738 }
1739 
1740 static int run_list_real(struct pipe *pi)
1741 {
1742 	char *save_name = NULL;
1743 	char **list = NULL;
1744 	char **save_list = NULL;
1745 	struct pipe *rpipe;
1746 	int flag_rep = 0;
1747 #ifndef __U_BOOT__
1748 	int save_num_progs;
1749 #endif
1750 	int rcode=0, flag_skip=1;
1751 	int flag_restore = 0;
1752 	int if_code=0, next_if_code=0;  /* need double-buffer to handle elif */
1753 	reserved_style rmode, skip_more_in_this_rmode=RES_XXXX;
1754 	/* check syntax for "for" */
1755 	for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1756 		if ((rpipe->r_mode == RES_IN ||
1757 		    rpipe->r_mode == RES_FOR) &&
1758 		    (rpipe->next == NULL)) {
1759 				syntax();
1760 #ifdef __U_BOOT__
1761 				flag_repeat = 0;
1762 #endif
1763 				return 1;
1764 		}
1765 		if ((rpipe->r_mode == RES_IN &&
1766 			(rpipe->next->r_mode == RES_IN &&
1767 			rpipe->next->progs->argv != NULL))||
1768 			(rpipe->r_mode == RES_FOR &&
1769 			rpipe->next->r_mode != RES_IN)) {
1770 				syntax();
1771 #ifdef __U_BOOT__
1772 				flag_repeat = 0;
1773 #endif
1774 				return 1;
1775 		}
1776 	}
1777 	for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1778 		if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
1779 			pi->r_mode == RES_FOR) {
1780 #ifdef __U_BOOT__
1781 				/* check Ctrl-C */
1782 				ctrlc();
1783 				if ((had_ctrlc())) {
1784 					return 1;
1785 				}
1786 #endif
1787 				flag_restore = 0;
1788 				if (!rpipe) {
1789 					flag_rep = 0;
1790 					rpipe = pi;
1791 				}
1792 		}
1793 		rmode = pi->r_mode;
1794 		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);
1795 		if (rmode == skip_more_in_this_rmode && flag_skip) {
1796 			if (pi->followup == PIPE_SEQ) flag_skip=0;
1797 			continue;
1798 		}
1799 		flag_skip = 1;
1800 		skip_more_in_this_rmode = RES_XXXX;
1801 		if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
1802 		if (rmode == RES_THEN &&  if_code) continue;
1803 		if (rmode == RES_ELSE && !if_code) continue;
1804 		if (rmode == RES_ELIF && !if_code) break;
1805 		if (rmode == RES_FOR && pi->num_progs) {
1806 			if (!list) {
1807 				/* if no variable values after "in" we skip "for" */
1808 				if (!pi->next->progs->argv) continue;
1809 				/* create list of variable values */
1810 				list = make_list_in(pi->next->progs->argv,
1811 					pi->progs->argv[0]);
1812 				save_list = list;
1813 				save_name = pi->progs->argv[0];
1814 				pi->progs->argv[0] = NULL;
1815 				flag_rep = 1;
1816 			}
1817 			if (!(*list)) {
1818 				free(pi->progs->argv[0]);
1819 				free(save_list);
1820 				list = NULL;
1821 				flag_rep = 0;
1822 				pi->progs->argv[0] = save_name;
1823 #ifndef __U_BOOT__
1824 				pi->progs->glob_result.gl_pathv[0] =
1825 					pi->progs->argv[0];
1826 #endif
1827 				continue;
1828 			} else {
1829 				/* insert new value from list for variable */
1830 				if (pi->progs->argv[0])
1831 					free(pi->progs->argv[0]);
1832 				pi->progs->argv[0] = *list++;
1833 #ifndef __U_BOOT__
1834 				pi->progs->glob_result.gl_pathv[0] =
1835 					pi->progs->argv[0];
1836 #endif
1837 			}
1838 		}
1839 		if (rmode == RES_IN) continue;
1840 		if (rmode == RES_DO) {
1841 			if (!flag_rep) continue;
1842 		}
1843 		if (rmode == RES_DONE) {
1844 			if (flag_rep) {
1845 				flag_restore = 1;
1846 			} else {
1847 				rpipe = NULL;
1848 			}
1849 		}
1850 		if (pi->num_progs == 0) continue;
1851 #ifndef __U_BOOT__
1852 		save_num_progs = pi->num_progs; /* save number of programs */
1853 #endif
1854 		rcode = run_pipe_real(pi);
1855 		debug_printf("run_pipe_real returned %d\n",rcode);
1856 #ifndef __U_BOOT__
1857 		if (rcode!=-1) {
1858 			/* We only ran a builtin: rcode was set by the return value
1859 			 * of run_pipe_real(), and we don't need to wait for anything. */
1860 		} else if (pi->followup==PIPE_BG) {
1861 			/* XXX check bash's behavior with nontrivial pipes */
1862 			/* XXX compute jobid */
1863 			/* XXX what does bash do with attempts to background builtins? */
1864 			insert_bg_job(pi);
1865 			rcode = EXIT_SUCCESS;
1866 		} else {
1867 			if (interactive) {
1868 				/* move the new process group into the foreground */
1869 				if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1870 					perror_msg("tcsetpgrp-3");
1871 				rcode = checkjobs(pi);
1872 				/* move the shell to the foreground */
1873 				if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1874 					perror_msg("tcsetpgrp-4");
1875 			} else {
1876 				rcode = checkjobs(pi);
1877 			}
1878 			debug_printf("checkjobs returned %d\n",rcode);
1879 		}
1880 		last_return_code=rcode;
1881 #else
1882 		if (rcode < -1) {
1883 			last_return_code = -rcode - 2;
1884 			return -2;	/* exit */
1885 		}
1886 		last_return_code=(rcode == 0) ? 0 : 1;
1887 #endif
1888 #ifndef __U_BOOT__
1889 		pi->num_progs = save_num_progs; /* restore number of programs */
1890 #endif
1891 		if ( rmode == RES_IF || rmode == RES_ELIF )
1892 			next_if_code=rcode;  /* can be overwritten a number of times */
1893 		if (rmode == RES_WHILE)
1894 			flag_rep = !last_return_code;
1895 		if (rmode == RES_UNTIL)
1896 			flag_rep = last_return_code;
1897 		if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
1898 		     (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
1899 			skip_more_in_this_rmode=rmode;
1900 #ifndef __U_BOOT__
1901 		checkjobs(NULL);
1902 #endif
1903 	}
1904 	return rcode;
1905 }
1906 
1907 /* broken, of course, but OK for testing */
1908 static char *indenter(int i)
1909 {
1910 	static char blanks[]="                                    ";
1911 	return &blanks[sizeof(blanks)-i-1];
1912 }
1913 
1914 /* return code is the exit status of the pipe */
1915 static int free_pipe(struct pipe *pi, int indent)
1916 {
1917 	char **p;
1918 	struct child_prog *child;
1919 #ifndef __U_BOOT__
1920 	struct redir_struct *r, *rnext;
1921 #endif
1922 	int a, i, ret_code=0;
1923 	char *ind = indenter(indent);
1924 
1925 #ifndef __U_BOOT__
1926 	if (pi->stopped_progs > 0)
1927 		return ret_code;
1928 	final_printf("%s run pipe: (pid %d)\n",ind,getpid());
1929 #endif
1930 	for (i=0; i<pi->num_progs; i++) {
1931 		child = &pi->progs[i];
1932 		final_printf("%s  command %d:\n",ind,i);
1933 		if (child->argv) {
1934 			for (a=0,p=child->argv; *p; a++,p++) {
1935 				final_printf("%s   argv[%d] = %s\n",ind,a,*p);
1936 			}
1937 #ifndef __U_BOOT__
1938 			globfree(&child->glob_result);
1939 #else
1940 			for (a = 0; a < child->argc; a++) {
1941 				free(child->argv[a]);
1942 			}
1943 			free(child->argv);
1944 			free(child->argv_nonnull);
1945 			child->argc = 0;
1946 #endif
1947 			child->argv=NULL;
1948 		} else if (child->group) {
1949 #ifndef __U_BOOT__
1950 			final_printf("%s   begin group (subshell:%d)\n",ind, child->subshell);
1951 #endif
1952 			ret_code = free_pipe_list(child->group,indent+3);
1953 			final_printf("%s   end group\n",ind);
1954 		} else {
1955 			final_printf("%s   (nil)\n",ind);
1956 		}
1957 #ifndef __U_BOOT__
1958 		for (r=child->redirects; r; r=rnext) {
1959 			final_printf("%s   redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
1960 			if (r->dup == -1) {
1961 				/* guard against the case >$FOO, where foo is unset or blank */
1962 				if (r->word.gl_pathv) {
1963 					final_printf(" %s\n", *r->word.gl_pathv);
1964 					globfree(&r->word);
1965 				}
1966 			} else {
1967 				final_printf("&%d\n", r->dup);
1968 			}
1969 			rnext=r->next;
1970 			free(r);
1971 		}
1972 		child->redirects=NULL;
1973 #endif
1974 	}
1975 	free(pi->progs);   /* children are an array, they get freed all at once */
1976 	pi->progs=NULL;
1977 	return ret_code;
1978 }
1979 
1980 static int free_pipe_list(struct pipe *head, int indent)
1981 {
1982 	int rcode=0;   /* if list has no members */
1983 	struct pipe *pi, *next;
1984 	char *ind = indenter(indent);
1985 	for (pi=head; pi; pi=next) {
1986 		final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
1987 		rcode = free_pipe(pi, indent);
1988 		final_printf("%s pipe followup code %d\n", ind, pi->followup);
1989 		next=pi->next;
1990 		pi->next=NULL;
1991 		free(pi);
1992 	}
1993 	return rcode;
1994 }
1995 
1996 /* Select which version we will use */
1997 static int run_list(struct pipe *pi)
1998 {
1999 	int rcode=0;
2000 #ifndef __U_BOOT__
2001 	if (fake_mode==0) {
2002 #endif
2003 		rcode = run_list_real(pi);
2004 #ifndef __U_BOOT__
2005 	}
2006 #endif
2007 	/* free_pipe_list has the side effect of clearing memory
2008 	 * In the long run that function can be merged with run_list_real,
2009 	 * but doing that now would hobble the debugging effort. */
2010 	free_pipe_list(pi,0);
2011 	return rcode;
2012 }
2013 
2014 /* The API for glob is arguably broken.  This routine pushes a non-matching
2015  * string into the output structure, removing non-backslashed backslashes.
2016  * If someone can prove me wrong, by performing this function within the
2017  * original glob(3) api, feel free to rewrite this routine into oblivion.
2018  * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
2019  * XXX broken if the last character is '\\', check that before calling.
2020  */
2021 #ifndef __U_BOOT__
2022 static int globhack(const char *src, int flags, glob_t *pglob)
2023 {
2024 	int cnt=0, pathc;
2025 	const char *s;
2026 	char *dest;
2027 	for (cnt=1, s=src; s && *s; s++) {
2028 		if (*s == '\\') s++;
2029 		cnt++;
2030 	}
2031 	dest = malloc(cnt);
2032 	if (!dest) return GLOB_NOSPACE;
2033 	if (!(flags & GLOB_APPEND)) {
2034 		pglob->gl_pathv=NULL;
2035 		pglob->gl_pathc=0;
2036 		pglob->gl_offs=0;
2037 		pglob->gl_offs=0;
2038 	}
2039 	pathc = ++pglob->gl_pathc;
2040 	pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
2041 	if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
2042 	pglob->gl_pathv[pathc-1]=dest;
2043 	pglob->gl_pathv[pathc]=NULL;
2044 	for (s=src; s && *s; s++, dest++) {
2045 		if (*s == '\\') s++;
2046 		*dest = *s;
2047 	}
2048 	*dest='\0';
2049 	return 0;
2050 }
2051 
2052 /* XXX broken if the last character is '\\', check that before calling */
2053 static int glob_needed(const char *s)
2054 {
2055 	for (; *s; s++) {
2056 		if (*s == '\\') s++;
2057 		if (strchr("*[?",*s)) return 1;
2058 	}
2059 	return 0;
2060 }
2061 
2062 #if 0
2063 static void globprint(glob_t *pglob)
2064 {
2065 	int i;
2066 	debug_printf("glob_t at %p:\n", pglob);
2067 	debug_printf("  gl_pathc=%d  gl_pathv=%p  gl_offs=%d  gl_flags=%d\n",
2068 		pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
2069 	for (i=0; i<pglob->gl_pathc; i++)
2070 		debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
2071 			pglob->gl_pathv[i], pglob->gl_pathv[i]);
2072 }
2073 #endif
2074 
2075 static int xglob(o_string *dest, int flags, glob_t *pglob)
2076 {
2077 	int gr;
2078 
2079 	/* short-circuit for null word */
2080 	/* we can code this better when the debug_printf's are gone */
2081 	if (dest->length == 0) {
2082 		if (dest->nonnull) {
2083 			/* bash man page calls this an "explicit" null */
2084 			gr = globhack(dest->data, flags, pglob);
2085 			debug_printf("globhack returned %d\n",gr);
2086 		} else {
2087 			return 0;
2088 		}
2089 	} else if (glob_needed(dest->data)) {
2090 		gr = glob(dest->data, flags, NULL, pglob);
2091 		debug_printf("glob returned %d\n",gr);
2092 		if (gr == GLOB_NOMATCH) {
2093 			/* quote removal, or more accurately, backslash removal */
2094 			gr = globhack(dest->data, flags, pglob);
2095 			debug_printf("globhack returned %d\n",gr);
2096 		}
2097 	} else {
2098 		gr = globhack(dest->data, flags, pglob);
2099 		debug_printf("globhack returned %d\n",gr);
2100 	}
2101 	if (gr == GLOB_NOSPACE)
2102 		error_msg_and_die("out of memory during glob");
2103 	if (gr != 0) { /* GLOB_ABORTED ? */
2104 		error_msg("glob(3) error %d",gr);
2105 	}
2106 	/* globprint(glob_target); */
2107 	return gr;
2108 }
2109 #endif
2110 
2111 #ifdef __U_BOOT__
2112 static char *get_dollar_var(char ch);
2113 #endif
2114 
2115 /* This is used to get/check local shell variables */
2116 char *get_local_var(const char *s)
2117 {
2118 	struct variables *cur;
2119 
2120 	if (!s)
2121 		return NULL;
2122 
2123 #ifdef __U_BOOT__
2124 	if (*s == '$')
2125 		return get_dollar_var(s[1]);
2126 #endif
2127 
2128 	for (cur = top_vars; cur; cur=cur->next)
2129 		if(strcmp(cur->name, s)==0)
2130 			return cur->value;
2131 	return NULL;
2132 }
2133 
2134 /* This is used to set local shell variables
2135    flg_export==0 if only local (not exporting) variable
2136    flg_export==1 if "new" exporting environ
2137    flg_export>1  if current startup environ (not call putenv()) */
2138 int set_local_var(const char *s, int flg_export)
2139 {
2140 	char *name, *value;
2141 	int result=0;
2142 	struct variables *cur;
2143 
2144 #ifdef __U_BOOT__
2145 	/* might be possible! */
2146 	if (!isalpha(*s))
2147 		return -1;
2148 #endif
2149 
2150 	name=strdup(s);
2151 
2152 #ifdef __U_BOOT__
2153 	if (getenv(name) != NULL) {
2154 		printf ("ERROR: "
2155 				"There is a global environment variable with the same name.\n");
2156 		free(name);
2157 		return -1;
2158 	}
2159 #endif
2160 	/* Assume when we enter this function that we are already in
2161 	 * NAME=VALUE format.  So the first order of business is to
2162 	 * split 's' on the '=' into 'name' and 'value' */
2163 	value = strchr(name, '=');
2164 	if (value == NULL && ++value == NULL) {
2165 		free(name);
2166 		return -1;
2167 	}
2168 	*value++ = 0;
2169 
2170 	for(cur = top_vars; cur; cur = cur->next) {
2171 		if(strcmp(cur->name, name)==0)
2172 			break;
2173 	}
2174 
2175 	if(cur) {
2176 		if(strcmp(cur->value, value)==0) {
2177 			if(flg_export>0 && cur->flg_export==0)
2178 				cur->flg_export=flg_export;
2179 			else
2180 				result++;
2181 		} else {
2182 			if(cur->flg_read_only) {
2183 				error_msg("%s: readonly variable", name);
2184 				result = -1;
2185 			} else {
2186 				if(flg_export>0 || cur->flg_export>1)
2187 					cur->flg_export=1;
2188 				free(cur->value);
2189 
2190 				cur->value = strdup(value);
2191 			}
2192 		}
2193 	} else {
2194 		cur = malloc(sizeof(struct variables));
2195 		if(!cur) {
2196 			result = -1;
2197 		} else {
2198 			cur->name = strdup(name);
2199 			if (cur->name == NULL) {
2200 				free(cur);
2201 				result = -1;
2202 			} else {
2203 				struct variables *bottom = top_vars;
2204 				cur->value = strdup(value);
2205 				cur->next = NULL;
2206 				cur->flg_export = flg_export;
2207 				cur->flg_read_only = 0;
2208 				while(bottom->next) bottom=bottom->next;
2209 				bottom->next = cur;
2210 			}
2211 		}
2212 	}
2213 
2214 #ifndef __U_BOOT__
2215 	if(result==0 && cur->flg_export==1) {
2216 		*(value-1) = '=';
2217 		result = putenv(name);
2218 	} else {
2219 #endif
2220 		free(name);
2221 #ifndef __U_BOOT__
2222 		if(result>0)            /* equivalent to previous set */
2223 			result = 0;
2224 	}
2225 #endif
2226 	return result;
2227 }
2228 
2229 void unset_local_var(const char *name)
2230 {
2231 	struct variables *cur;
2232 
2233 	if (name) {
2234 		for (cur = top_vars; cur; cur=cur->next) {
2235 			if(strcmp(cur->name, name)==0)
2236 				break;
2237 		}
2238 		if (cur != NULL) {
2239 			struct variables *next = top_vars;
2240 			if(cur->flg_read_only) {
2241 				error_msg("%s: readonly variable", name);
2242 				return;
2243 			} else {
2244 #ifndef __U_BOOT__
2245 				if(cur->flg_export)
2246 					unsetenv(cur->name);
2247 #endif
2248 				free(cur->name);
2249 				free(cur->value);
2250 				while (next->next != cur)
2251 					next = next->next;
2252 				next->next = cur->next;
2253 			}
2254 			free(cur);
2255 		}
2256 	}
2257 }
2258 
2259 static int is_assignment(const char *s)
2260 {
2261 	if (s == NULL)
2262 		return 0;
2263 
2264 	if (!isalpha(*s)) return 0;
2265 	++s;
2266 	while(isalnum(*s) || *s=='_') ++s;
2267 	return *s=='=';
2268 }
2269 
2270 #ifndef __U_BOOT__
2271 /* the src parameter allows us to peek forward to a possible &n syntax
2272  * for file descriptor duplication, e.g., "2>&1".
2273  * Return code is 0 normally, 1 if a syntax error is detected in src.
2274  * Resource errors (in xmalloc) cause the process to exit */
2275 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
2276 	struct in_str *input)
2277 {
2278 	struct child_prog *child=ctx->child;
2279 	struct redir_struct *redir = child->redirects;
2280 	struct redir_struct *last_redir=NULL;
2281 
2282 	/* Create a new redir_struct and drop it onto the end of the linked list */
2283 	while(redir) {
2284 		last_redir=redir;
2285 		redir=redir->next;
2286 	}
2287 	redir = xmalloc(sizeof(struct redir_struct));
2288 	redir->next=NULL;
2289 	redir->word.gl_pathv=NULL;
2290 	if (last_redir) {
2291 		last_redir->next=redir;
2292 	} else {
2293 		child->redirects=redir;
2294 	}
2295 
2296 	redir->type=style;
2297 	redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
2298 
2299 	debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
2300 
2301 	/* Check for a '2>&1' type redirect */
2302 	redir->dup = redirect_dup_num(input);
2303 	if (redir->dup == -2) return 1;  /* syntax error */
2304 	if (redir->dup != -1) {
2305 		/* Erik had a check here that the file descriptor in question
2306 		 * is legit; I postpone that to "run time"
2307 		 * A "-" representation of "close me" shows up as a -3 here */
2308 		debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
2309 	} else {
2310 		/* We do _not_ try to open the file that src points to,
2311 		 * since we need to return and let src be expanded first.
2312 		 * Set ctx->pending_redirect, so we know what to do at the
2313 		 * end of the next parsed word.
2314 		 */
2315 		ctx->pending_redirect = redir;
2316 	}
2317 	return 0;
2318 }
2319 #endif
2320 
2321 static struct pipe *new_pipe(void)
2322 {
2323 	struct pipe *pi;
2324 	pi = xmalloc(sizeof(struct pipe));
2325 	pi->num_progs = 0;
2326 	pi->progs = NULL;
2327 	pi->next = NULL;
2328 	pi->followup = 0;  /* invalid */
2329 	pi->r_mode = RES_NONE;
2330 	return pi;
2331 }
2332 
2333 static void initialize_context(struct p_context *ctx)
2334 {
2335 	ctx->pipe=NULL;
2336 #ifndef __U_BOOT__
2337 	ctx->pending_redirect=NULL;
2338 #endif
2339 	ctx->child=NULL;
2340 	ctx->list_head=new_pipe();
2341 	ctx->pipe=ctx->list_head;
2342 	ctx->w=RES_NONE;
2343 	ctx->stack=NULL;
2344 #ifdef __U_BOOT__
2345 	ctx->old_flag=0;
2346 #endif
2347 	done_command(ctx);   /* creates the memory for working child */
2348 }
2349 
2350 /* normal return is 0
2351  * if a reserved word is found, and processed, return 1
2352  * should handle if, then, elif, else, fi, for, while, until, do, done.
2353  * case, function, and select are obnoxious, save those for later.
2354  */
2355 struct reserved_combo {
2356 	char *literal;
2357 	int code;
2358 	long flag;
2359 };
2360 /* Mostly a list of accepted follow-up reserved words.
2361  * FLAG_END means we are done with the sequence, and are ready
2362  * to turn the compound list into a command.
2363  * FLAG_START means the word must start a new compound list.
2364  */
2365 static struct reserved_combo reserved_list[] = {
2366 	{ "if",    RES_IF,    FLAG_THEN | FLAG_START },
2367 	{ "then",  RES_THEN,  FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2368 	{ "elif",  RES_ELIF,  FLAG_THEN },
2369 	{ "else",  RES_ELSE,  FLAG_FI   },
2370 	{ "fi",    RES_FI,    FLAG_END  },
2371 	{ "for",   RES_FOR,   FLAG_IN   | FLAG_START },
2372 	{ "while", RES_WHILE, FLAG_DO   | FLAG_START },
2373 	{ "until", RES_UNTIL, FLAG_DO   | FLAG_START },
2374 	{ "in",    RES_IN,    FLAG_DO   },
2375 	{ "do",    RES_DO,    FLAG_DONE },
2376 	{ "done",  RES_DONE,  FLAG_END  }
2377 };
2378 #define NRES (sizeof(reserved_list)/sizeof(struct reserved_combo))
2379 
2380 static int reserved_word(o_string *dest, struct p_context *ctx)
2381 {
2382 	struct reserved_combo *r;
2383 	for (r=reserved_list;
2384 		r<reserved_list+NRES; r++) {
2385 		if (strcmp(dest->data, r->literal) == 0) {
2386 			debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2387 			if (r->flag & FLAG_START) {
2388 				struct p_context *new = xmalloc(sizeof(struct p_context));
2389 				debug_printf("push stack\n");
2390 				if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2391 					syntax();
2392 					free(new);
2393 					ctx->w = RES_SNTX;
2394 					b_reset(dest);
2395 					return 1;
2396 				}
2397 				*new = *ctx;   /* physical copy */
2398 				initialize_context(ctx);
2399 				ctx->stack=new;
2400 			} else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2401 				syntax();
2402 				ctx->w = RES_SNTX;
2403 				b_reset(dest);
2404 				return 1;
2405 			}
2406 			ctx->w=r->code;
2407 			ctx->old_flag = r->flag;
2408 			if (ctx->old_flag & FLAG_END) {
2409 				struct p_context *old;
2410 				debug_printf("pop stack\n");
2411 				done_pipe(ctx,PIPE_SEQ);
2412 				old = ctx->stack;
2413 				old->child->group = ctx->list_head;
2414 #ifndef __U_BOOT__
2415 				old->child->subshell = 0;
2416 #endif
2417 				*ctx = *old;   /* physical copy */
2418 				free(old);
2419 			}
2420 			b_reset (dest);
2421 			return 1;
2422 		}
2423 	}
2424 	return 0;
2425 }
2426 
2427 /* normal return is 0.
2428  * Syntax or xglob errors return 1. */
2429 static int done_word(o_string *dest, struct p_context *ctx)
2430 {
2431 	struct child_prog *child=ctx->child;
2432 #ifndef __U_BOOT__
2433 	glob_t *glob_target;
2434 	int gr, flags = 0;
2435 #else
2436 	char *str, *s;
2437 	int argc, cnt;
2438 #endif
2439 
2440 	debug_printf("done_word: %s %p\n", dest->data, child);
2441 	if (dest->length == 0 && !dest->nonnull) {
2442 		debug_printf("  true null, ignored\n");
2443 		return 0;
2444 	}
2445 #ifndef __U_BOOT__
2446 	if (ctx->pending_redirect) {
2447 		glob_target = &ctx->pending_redirect->word;
2448 	} else {
2449 #endif
2450 		if (child->group) {
2451 			syntax();
2452 			return 1;  /* syntax error, groups and arglists don't mix */
2453 		}
2454 		if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2455 			debug_printf("checking %s for reserved-ness\n",dest->data);
2456 			if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2457 		}
2458 #ifndef __U_BOOT__
2459 		glob_target = &child->glob_result;
2460 		if (child->argv) flags |= GLOB_APPEND;
2461 #else
2462 		for (cnt = 1, s = dest->data; s && *s; s++) {
2463 			if (*s == '\\') s++;
2464 			cnt++;
2465 		}
2466 		str = malloc(cnt);
2467 		if (!str) return 1;
2468 		if ( child->argv == NULL) {
2469 			child->argc=0;
2470 		}
2471 		argc = ++child->argc;
2472 		child->argv = realloc(child->argv, (argc+1)*sizeof(*child->argv));
2473 		if (child->argv == NULL) return 1;
2474 		child->argv_nonnull = realloc(child->argv_nonnull,
2475 					(argc+1)*sizeof(*child->argv_nonnull));
2476 		if (child->argv_nonnull == NULL)
2477 			return 1;
2478 		child->argv[argc-1]=str;
2479 		child->argv_nonnull[argc-1] = dest->nonnull;
2480 		child->argv[argc]=NULL;
2481 		child->argv_nonnull[argc] = 0;
2482 		for (s = dest->data; s && *s; s++,str++) {
2483 			if (*s == '\\') s++;
2484 			*str = *s;
2485 		}
2486 		*str = '\0';
2487 #endif
2488 #ifndef __U_BOOT__
2489 	}
2490 	gr = xglob(dest, flags, glob_target);
2491 	if (gr != 0) return 1;
2492 #endif
2493 
2494 	b_reset(dest);
2495 #ifndef __U_BOOT__
2496 	if (ctx->pending_redirect) {
2497 		ctx->pending_redirect=NULL;
2498 		if (glob_target->gl_pathc != 1) {
2499 			error_msg("ambiguous redirect");
2500 			return 1;
2501 		}
2502 	} else {
2503 		child->argv = glob_target->gl_pathv;
2504 	}
2505 #endif
2506 	if (ctx->w == RES_FOR) {
2507 		done_word(dest,ctx);
2508 		done_pipe(ctx,PIPE_SEQ);
2509 	}
2510 	return 0;
2511 }
2512 
2513 /* The only possible error here is out of memory, in which case
2514  * xmalloc exits. */
2515 static int done_command(struct p_context *ctx)
2516 {
2517 	/* The child is really already in the pipe structure, so
2518 	 * advance the pipe counter and make a new, null child.
2519 	 * Only real trickiness here is that the uncommitted
2520 	 * child structure, to which ctx->child points, is not
2521 	 * counted in pi->num_progs. */
2522 	struct pipe *pi=ctx->pipe;
2523 	struct child_prog *prog=ctx->child;
2524 
2525 	if (prog && prog->group == NULL
2526 		 && prog->argv == NULL
2527 #ifndef __U_BOOT__
2528 		 && prog->redirects == NULL) {
2529 #else
2530 										) {
2531 #endif
2532 		debug_printf("done_command: skipping null command\n");
2533 		return 0;
2534 	} else if (prog) {
2535 		pi->num_progs++;
2536 		debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2537 	} else {
2538 		debug_printf("done_command: initializing\n");
2539 	}
2540 	pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2541 
2542 	prog = pi->progs + pi->num_progs;
2543 #ifndef __U_BOOT__
2544 	prog->redirects = NULL;
2545 #endif
2546 	prog->argv = NULL;
2547 	prog->argv_nonnull = NULL;
2548 #ifndef __U_BOOT__
2549 	prog->is_stopped = 0;
2550 #endif
2551 	prog->group = NULL;
2552 #ifndef __U_BOOT__
2553 	prog->glob_result.gl_pathv = NULL;
2554 	prog->family = pi;
2555 #endif
2556 	prog->sp = 0;
2557 	ctx->child = prog;
2558 	prog->type = ctx->type;
2559 
2560 	/* but ctx->pipe and ctx->list_head remain unchanged */
2561 	return 0;
2562 }
2563 
2564 static int done_pipe(struct p_context *ctx, pipe_style type)
2565 {
2566 	struct pipe *new_p;
2567 	done_command(ctx);  /* implicit closure of previous command */
2568 	debug_printf("done_pipe, type %d\n", type);
2569 	ctx->pipe->followup = type;
2570 	ctx->pipe->r_mode = ctx->w;
2571 	new_p=new_pipe();
2572 	ctx->pipe->next = new_p;
2573 	ctx->pipe = new_p;
2574 	ctx->child = NULL;
2575 	done_command(ctx);  /* set up new pipe to accept commands */
2576 	return 0;
2577 }
2578 
2579 #ifndef __U_BOOT__
2580 /* peek ahead in the in_str to find out if we have a "&n" construct,
2581  * as in "2>&1", that represents duplicating a file descriptor.
2582  * returns either -2 (syntax error), -1 (no &), or the number found.
2583  */
2584 static int redirect_dup_num(struct in_str *input)
2585 {
2586 	int ch, d=0, ok=0;
2587 	ch = b_peek(input);
2588 	if (ch != '&') return -1;
2589 
2590 	b_getch(input);  /* get the & */
2591 	ch=b_peek(input);
2592 	if (ch == '-') {
2593 		b_getch(input);
2594 		return -3;  /* "-" represents "close me" */
2595 	}
2596 	while (isdigit(ch)) {
2597 		d = d*10+(ch-'0');
2598 		ok=1;
2599 		b_getch(input);
2600 		ch = b_peek(input);
2601 	}
2602 	if (ok) return d;
2603 
2604 	error_msg("ambiguous redirect");
2605 	return -2;
2606 }
2607 
2608 /* If a redirect is immediately preceded by a number, that number is
2609  * supposed to tell which file descriptor to redirect.  This routine
2610  * looks for such preceding numbers.  In an ideal world this routine
2611  * needs to handle all the following classes of redirects...
2612  *     echo 2>foo     # redirects fd  2 to file "foo", nothing passed to echo
2613  *     echo 49>foo    # redirects fd 49 to file "foo", nothing passed to echo
2614  *     echo -2>foo    # redirects fd  1 to file "foo",    "-2" passed to echo
2615  *     echo 49x>foo   # redirects fd  1 to file "foo",   "49x" passed to echo
2616  * A -1 output from this program means no valid number was found, so the
2617  * caller should use the appropriate default for this redirection.
2618  */
2619 static int redirect_opt_num(o_string *o)
2620 {
2621 	int num;
2622 
2623 	if (o->length==0) return -1;
2624 	for(num=0; num<o->length; num++) {
2625 		if (!isdigit(*(o->data+num))) {
2626 			return -1;
2627 		}
2628 	}
2629 	/* reuse num (and save an int) */
2630 	num=atoi(o->data);
2631 	b_reset(o);
2632 	return num;
2633 }
2634 
2635 FILE *generate_stream_from_list(struct pipe *head)
2636 {
2637 	FILE *pf;
2638 #if 1
2639 	int pid, channel[2];
2640 	if (pipe(channel)<0) perror_msg_and_die("pipe");
2641 	pid=fork();
2642 	if (pid<0) {
2643 		perror_msg_and_die("fork");
2644 	} else if (pid==0) {
2645 		close(channel[0]);
2646 		if (channel[1] != 1) {
2647 			dup2(channel[1],1);
2648 			close(channel[1]);
2649 		}
2650 #if 0
2651 #define SURROGATE "surrogate response"
2652 		write(1,SURROGATE,sizeof(SURROGATE));
2653 		_exit(run_list(head));
2654 #else
2655 		_exit(run_list_real(head));   /* leaks memory */
2656 #endif
2657 	}
2658 	debug_printf("forked child %d\n",pid);
2659 	close(channel[1]);
2660 	pf = fdopen(channel[0],"r");
2661 	debug_printf("pipe on FILE *%p\n",pf);
2662 #else
2663 	free_pipe_list(head,0);
2664 	pf=popen("echo surrogate response","r");
2665 	debug_printf("started fake pipe on FILE *%p\n",pf);
2666 #endif
2667 	return pf;
2668 }
2669 
2670 /* this version hacked for testing purposes */
2671 /* return code is exit status of the process that is run. */
2672 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2673 {
2674 	int retcode;
2675 	o_string result=NULL_O_STRING;
2676 	struct p_context inner;
2677 	FILE *p;
2678 	struct in_str pipe_str;
2679 	initialize_context(&inner);
2680 
2681 	/* recursion to generate command */
2682 	retcode = parse_stream(&result, &inner, input, subst_end);
2683 	if (retcode != 0) return retcode;  /* syntax error or EOF */
2684 	done_word(&result, &inner);
2685 	done_pipe(&inner, PIPE_SEQ);
2686 	b_free(&result);
2687 
2688 	p=generate_stream_from_list(inner.list_head);
2689 	if (p==NULL) return 1;
2690 	mark_open(fileno(p));
2691 	setup_file_in_str(&pipe_str, p);
2692 
2693 	/* now send results of command back into original context */
2694 	retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2695 	/* XXX In case of a syntax error, should we try to kill the child?
2696 	 * That would be tough to do right, so just read until EOF. */
2697 	if (retcode == 1) {
2698 		while (b_getch(&pipe_str)!=EOF) { /* discard */ };
2699 	}
2700 
2701 	debug_printf("done reading from pipe, pclose()ing\n");
2702 	/* This is the step that wait()s for the child.  Should be pretty
2703 	 * safe, since we just read an EOF from its stdout.  We could try
2704 	 * to better, by using wait(), and keeping track of background jobs
2705 	 * at the same time.  That would be a lot of work, and contrary
2706 	 * to the KISS philosophy of this program. */
2707 	mark_closed(fileno(p));
2708 	retcode=pclose(p);
2709 	free_pipe_list(inner.list_head,0);
2710 	debug_printf("pclosed, retcode=%d\n",retcode);
2711 	/* XXX this process fails to trim a single trailing newline */
2712 	return retcode;
2713 }
2714 
2715 static int parse_group(o_string *dest, struct p_context *ctx,
2716 	struct in_str *input, int ch)
2717 {
2718 	int rcode, endch=0;
2719 	struct p_context sub;
2720 	struct child_prog *child = ctx->child;
2721 	if (child->argv) {
2722 		syntax();
2723 		return 1;  /* syntax error, groups and arglists don't mix */
2724 	}
2725 	initialize_context(&sub);
2726 	switch(ch) {
2727 		case '(': endch=')'; child->subshell=1; break;
2728 		case '{': endch='}'; break;
2729 		default: syntax();   /* really logic error */
2730 	}
2731 	rcode=parse_stream(dest,&sub,input,endch);
2732 	done_word(dest,&sub); /* finish off the final word in the subcontext */
2733 	done_pipe(&sub, PIPE_SEQ);  /* and the final command there, too */
2734 	child->group = sub.list_head;
2735 	return rcode;
2736 	/* child remains "open", available for possible redirects */
2737 }
2738 #endif
2739 
2740 /* basically useful version until someone wants to get fancier,
2741  * see the bash man page under "Parameter Expansion" */
2742 static char *lookup_param(char *src)
2743 {
2744 	char *p;
2745 	char *sep;
2746 	char *default_val = NULL;
2747 	int assign = 0;
2748 	int expand_empty = 0;
2749 
2750 	if (!src)
2751 		return NULL;
2752 
2753 	sep = strchr(src, ':');
2754 
2755 	if (sep) {
2756 		*sep = '\0';
2757 		if (*(sep + 1) == '-')
2758 			default_val = sep+2;
2759 		if (*(sep + 1) == '=') {
2760 			default_val = sep+2;
2761 			assign = 1;
2762 		}
2763 		if (*(sep + 1) == '+') {
2764 			default_val = sep+2;
2765 			expand_empty = 1;
2766 		}
2767 	}
2768 
2769 	p = getenv(src);
2770 	if (!p)
2771 		p = get_local_var(src);
2772 
2773 	if (!p || strlen(p) == 0) {
2774 		p = default_val;
2775 		if (assign) {
2776 			char *var = malloc(strlen(src)+strlen(default_val)+2);
2777 			if (var) {
2778 				sprintf(var, "%s=%s", src, default_val);
2779 				set_local_var(var, 0);
2780 			}
2781 			free(var);
2782 		}
2783 	} else if (expand_empty) {
2784 		p += strlen(p);
2785 	}
2786 
2787 	if (sep)
2788 		*sep = ':';
2789 
2790 	return p;
2791 }
2792 
2793 #ifdef __U_BOOT__
2794 static char *get_dollar_var(char ch)
2795 {
2796 	static char buf[40];
2797 
2798 	buf[0] = '\0';
2799 	switch (ch) {
2800 		case '?':
2801 			sprintf(buf, "%u", (unsigned int)last_return_code);
2802 			break;
2803 		default:
2804 			return NULL;
2805 	}
2806 	return buf;
2807 }
2808 #endif
2809 
2810 /* return code: 0 for OK, 1 for syntax error */
2811 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2812 {
2813 #ifndef __U_BOOT__
2814 	int i, advance=0;
2815 #else
2816 	int advance=0;
2817 #endif
2818 #ifndef __U_BOOT__
2819 	char sep[]=" ";
2820 #endif
2821 	int ch = input->peek(input);  /* first character after the $ */
2822 	debug_printf("handle_dollar: ch=%c\n",ch);
2823 	if (isalpha(ch)) {
2824 		b_addchr(dest, SPECIAL_VAR_SYMBOL);
2825 		ctx->child->sp++;
2826 		while(ch=b_peek(input),isalnum(ch) || ch=='_') {
2827 			b_getch(input);
2828 			b_addchr(dest,ch);
2829 		}
2830 		b_addchr(dest, SPECIAL_VAR_SYMBOL);
2831 #ifndef __U_BOOT__
2832 	} else if (isdigit(ch)) {
2833 		i = ch-'0';  /* XXX is $0 special? */
2834 		if (i<global_argc) {
2835 			parse_string(dest, ctx, global_argv[i]); /* recursion */
2836 		}
2837 		advance = 1;
2838 #endif
2839 	} else switch (ch) {
2840 #ifndef __U_BOOT__
2841 		case '$':
2842 			b_adduint(dest,getpid());
2843 			advance = 1;
2844 			break;
2845 		case '!':
2846 			if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2847 			advance = 1;
2848 			break;
2849 #endif
2850 		case '?':
2851 #ifndef __U_BOOT__
2852 			b_adduint(dest,last_return_code);
2853 #else
2854 			ctx->child->sp++;
2855 			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2856 			b_addchr(dest, '$');
2857 			b_addchr(dest, '?');
2858 			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2859 #endif
2860 			advance = 1;
2861 			break;
2862 #ifndef __U_BOOT__
2863 		case '#':
2864 			b_adduint(dest,global_argc ? global_argc-1 : 0);
2865 			advance = 1;
2866 			break;
2867 #endif
2868 		case '{':
2869 			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2870 			ctx->child->sp++;
2871 			b_getch(input);
2872 			/* XXX maybe someone will try to escape the '}' */
2873 			while(ch=b_getch(input),ch!=EOF && ch!='}') {
2874 				b_addchr(dest,ch);
2875 			}
2876 			if (ch != '}') {
2877 				syntax();
2878 				return 1;
2879 			}
2880 			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2881 			break;
2882 #ifndef __U_BOOT__
2883 		case '(':
2884 			b_getch(input);
2885 			process_command_subs(dest, ctx, input, ')');
2886 			break;
2887 		case '*':
2888 			sep[0]=ifs[0];
2889 			for (i=1; i<global_argc; i++) {
2890 				parse_string(dest, ctx, global_argv[i]);
2891 				if (i+1 < global_argc) parse_string(dest, ctx, sep);
2892 			}
2893 			break;
2894 		case '@':
2895 		case '-':
2896 		case '_':
2897 			/* still unhandled, but should be eventually */
2898 			error_msg("unhandled syntax: $%c",ch);
2899 			return 1;
2900 			break;
2901 #endif
2902 		default:
2903 			b_addqchr(dest,'$',dest->quote);
2904 	}
2905 	/* Eat the character if the flag was set.  If the compiler
2906 	 * is smart enough, we could substitute "b_getch(input);"
2907 	 * for all the "advance = 1;" above, and also end up with
2908 	 * a nice size-optimized program.  Hah!  That'll be the day.
2909 	 */
2910 	if (advance) b_getch(input);
2911 	return 0;
2912 }
2913 
2914 #ifndef __U_BOOT__
2915 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2916 {
2917 	struct in_str foo;
2918 	setup_string_in_str(&foo, src);
2919 	return parse_stream(dest, ctx, &foo, '\0');
2920 }
2921 #endif
2922 
2923 /* return code is 0 for normal exit, 1 for syntax error */
2924 static int parse_stream(o_string *dest, struct p_context *ctx,
2925 			struct in_str *input, int end_trigger)
2926 {
2927 	unsigned int ch, m;
2928 #ifndef __U_BOOT__
2929 	int redir_fd;
2930 	redir_type redir_style;
2931 #endif
2932 	int next;
2933 
2934 	/* Only double-quote state is handled in the state variable dest->quote.
2935 	 * A single-quote triggers a bypass of the main loop until its mate is
2936 	 * found.  When recursing, quote state is passed in via dest->quote. */
2937 
2938 	debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2939 	while ((ch=b_getch(input))!=EOF) {
2940 		m = map[ch];
2941 #ifdef __U_BOOT__
2942 		if (input->__promptme == 0) return 1;
2943 #endif
2944 		next = (ch == '\n') ? 0 : b_peek(input);
2945 
2946 		debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d - %c\n",
2947 			ch >= ' ' ? ch : '.', ch, m,
2948 			dest->quote, ctx->stack == NULL ? '*' : '.');
2949 
2950 		if (m==0 || ((m==1 || m==2) && dest->quote)) {
2951 			b_addqchr(dest, ch, dest->quote);
2952 		} else {
2953 			if (m==2) {  /* unquoted IFS */
2954 				if (done_word(dest, ctx)) {
2955 					return 1;
2956 				}
2957 				/* If we aren't performing a substitution, treat a newline as a
2958 				 * command separator.  */
2959 				if (end_trigger != '\0' && ch=='\n')
2960 					done_pipe(ctx,PIPE_SEQ);
2961 			}
2962 			if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2963 				debug_printf("leaving parse_stream (triggered)\n");
2964 				return 0;
2965 			}
2966 #if 0
2967 			if (ch=='\n') {
2968 				/* Yahoo!  Time to run with it! */
2969 				done_pipe(ctx,PIPE_SEQ);
2970 				run_list(ctx->list_head);
2971 				initialize_context(ctx);
2972 			}
2973 #endif
2974 			if (m!=2) switch (ch) {
2975 		case '#':
2976 			if (dest->length == 0 && !dest->quote) {
2977 				while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
2978 			} else {
2979 				b_addqchr(dest, ch, dest->quote);
2980 			}
2981 			break;
2982 		case '\\':
2983 			if (next == EOF) {
2984 				syntax();
2985 				return 1;
2986 			}
2987 			b_addqchr(dest, '\\', dest->quote);
2988 			b_addqchr(dest, b_getch(input), dest->quote);
2989 			break;
2990 		case '$':
2991 			if (handle_dollar(dest, ctx, input)!=0) return 1;
2992 			break;
2993 		case '\'':
2994 			dest->nonnull = 1;
2995 			while(ch=b_getch(input),ch!=EOF && ch!='\'') {
2996 #ifdef __U_BOOT__
2997 				if(input->__promptme == 0) return 1;
2998 #endif
2999 				b_addchr(dest,ch);
3000 			}
3001 			if (ch==EOF) {
3002 				syntax();
3003 				return 1;
3004 			}
3005 			break;
3006 		case '"':
3007 			dest->nonnull = 1;
3008 			dest->quote = !dest->quote;
3009 			break;
3010 #ifndef __U_BOOT__
3011 		case '`':
3012 			process_command_subs(dest, ctx, input, '`');
3013 			break;
3014 		case '>':
3015 			redir_fd = redirect_opt_num(dest);
3016 			done_word(dest, ctx);
3017 			redir_style=REDIRECT_OVERWRITE;
3018 			if (next == '>') {
3019 				redir_style=REDIRECT_APPEND;
3020 				b_getch(input);
3021 			} else if (next == '(') {
3022 				syntax();   /* until we support >(list) Process Substitution */
3023 				return 1;
3024 			}
3025 			setup_redirect(ctx, redir_fd, redir_style, input);
3026 			break;
3027 		case '<':
3028 			redir_fd = redirect_opt_num(dest);
3029 			done_word(dest, ctx);
3030 			redir_style=REDIRECT_INPUT;
3031 			if (next == '<') {
3032 				redir_style=REDIRECT_HEREIS;
3033 				b_getch(input);
3034 			} else if (next == '>') {
3035 				redir_style=REDIRECT_IO;
3036 				b_getch(input);
3037 			} else if (next == '(') {
3038 				syntax();   /* until we support <(list) Process Substitution */
3039 				return 1;
3040 			}
3041 			setup_redirect(ctx, redir_fd, redir_style, input);
3042 			break;
3043 #endif
3044 		case ';':
3045 			done_word(dest, ctx);
3046 			done_pipe(ctx,PIPE_SEQ);
3047 			break;
3048 		case '&':
3049 			done_word(dest, ctx);
3050 			if (next=='&') {
3051 				b_getch(input);
3052 				done_pipe(ctx,PIPE_AND);
3053 			} else {
3054 #ifndef __U_BOOT__
3055 				done_pipe(ctx,PIPE_BG);
3056 #else
3057 				syntax_err();
3058 				return 1;
3059 #endif
3060 			}
3061 			break;
3062 		case '|':
3063 			done_word(dest, ctx);
3064 			if (next=='|') {
3065 				b_getch(input);
3066 				done_pipe(ctx,PIPE_OR);
3067 			} else {
3068 				/* we could pick up a file descriptor choice here
3069 				 * with redirect_opt_num(), but bash doesn't do it.
3070 				 * "echo foo 2| cat" yields "foo 2". */
3071 #ifndef __U_BOOT__
3072 				done_command(ctx);
3073 #else
3074 				syntax_err();
3075 				return 1;
3076 #endif
3077 			}
3078 			break;
3079 #ifndef __U_BOOT__
3080 		case '(':
3081 		case '{':
3082 			if (parse_group(dest, ctx, input, ch)!=0) return 1;
3083 			break;
3084 		case ')':
3085 		case '}':
3086 			syntax();   /* Proper use of this character caught by end_trigger */
3087 			return 1;
3088 			break;
3089 #endif
3090 		case SUBSTED_VAR_SYMBOL:
3091 			dest->nonnull = 1;
3092 			while (ch = b_getch(input), ch != EOF &&
3093 			    ch != SUBSTED_VAR_SYMBOL) {
3094 				debug_printf("subst, pass=%d\n", ch);
3095 				if (input->__promptme == 0)
3096 					return 1;
3097 				b_addchr(dest, ch);
3098 			}
3099 			debug_printf("subst, term=%d\n", ch);
3100 			if (ch == EOF) {
3101 				syntax();
3102 				return 1;
3103 			}
3104 			break;
3105 		default:
3106 			syntax();   /* this is really an internal logic error */
3107 			return 1;
3108 			}
3109 		}
3110 	}
3111 	/* complain if quote?  No, maybe we just finished a command substitution
3112 	 * that was quoted.  Example:
3113 	 * $ echo "`cat foo` plus more"
3114 	 * and we just got the EOF generated by the subshell that ran "cat foo"
3115 	 * The only real complaint is if we got an EOF when end_trigger != '\0',
3116 	 * that is, we were really supposed to get end_trigger, and never got
3117 	 * one before the EOF.  Can't use the standard "syntax error" return code,
3118 	 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
3119 	debug_printf("leaving parse_stream (EOF)\n");
3120 	if (end_trigger != '\0') return -1;
3121 	return 0;
3122 }
3123 
3124 static void mapset(const unsigned char *set, int code)
3125 {
3126 	const unsigned char *s;
3127 	for (s=set; *s; s++) map[*s] = code;
3128 }
3129 
3130 static void update_ifs_map(void)
3131 {
3132 	/* char *ifs and char map[256] are both globals. */
3133 	ifs = (uchar *)getenv("IFS");
3134 	if (ifs == NULL) ifs=(uchar *)" \t\n";
3135 	/* Precompute a list of 'flow through' behavior so it can be treated
3136 	 * quickly up front.  Computation is necessary because of IFS.
3137 	 * Special case handling of IFS == " \t\n" is not implemented.
3138 	 * The map[] array only really needs two bits each, and on most machines
3139 	 * that would be faster because of the reduced L1 cache footprint.
3140 	 */
3141 	memset(map,0,sizeof(map)); /* most characters flow through always */
3142 #ifndef __U_BOOT__
3143 	mapset((uchar *)"\\$'\"`", 3);      /* never flow through */
3144 	mapset((uchar *)"<>;&|(){}#", 1);   /* flow through if quoted */
3145 #else
3146 	{
3147 		uchar subst[2] = {SUBSTED_VAR_SYMBOL, 0};
3148 		mapset(subst, 3);       /* never flow through */
3149 	}
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 static 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 = 1;
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,
3174 				     flag & FLAG_CONT_ON_NEWLINE ? -1 : '\n');
3175 #ifdef __U_BOOT__
3176 		if (rcode == 1) flag_repeat = 0;
3177 #endif
3178 		if (rcode != 1 && ctx.old_flag != 0) {
3179 			syntax();
3180 #ifdef __U_BOOT__
3181 			flag_repeat = 0;
3182 #endif
3183 		}
3184 		if (rcode != 1 && ctx.old_flag == 0) {
3185 			done_word(&temp, &ctx);
3186 			done_pipe(&ctx,PIPE_SEQ);
3187 #ifndef __U_BOOT__
3188 			run_list(ctx.list_head);
3189 #else
3190 			code = run_list(ctx.list_head);
3191 			if (code == -2) {	/* exit */
3192 				b_free(&temp);
3193 				code = 0;
3194 				/* XXX hackish way to not allow exit from main loop */
3195 				if (inp->peek == file_peek) {
3196 					printf("exit not allowed from main input shell.\n");
3197 					continue;
3198 				}
3199 				break;
3200 			}
3201 			if (code == -1)
3202 			    flag_repeat = 0;
3203 #endif
3204 		} else {
3205 			if (ctx.old_flag != 0) {
3206 				free(ctx.stack);
3207 				b_reset(&temp);
3208 			}
3209 #ifdef __U_BOOT__
3210 			if (inp->__promptme == 0) printf("<INTERRUPT>\n");
3211 			inp->__promptme = 1;
3212 #endif
3213 			temp.nonnull = 0;
3214 			temp.quote = 0;
3215 			inp->p = NULL;
3216 			free_pipe_list(ctx.list_head,0);
3217 		}
3218 		b_free(&temp);
3219 	/* loop on syntax errors, return on EOF */
3220 	} while (rcode != 1 && !(flag & FLAG_EXIT_FROM_LOOP) &&
3221 		(inp->peek != static_peek || b_peek(inp)));
3222 #ifndef __U_BOOT__
3223 	return 0;
3224 #else
3225 	return (code != 0) ? 1 : 0;
3226 #endif /* __U_BOOT__ */
3227 }
3228 
3229 #ifndef __U_BOOT__
3230 static int parse_string_outer(const char *s, int flag)
3231 #else
3232 int parse_string_outer(const char *s, int flag)
3233 #endif	/* __U_BOOT__ */
3234 {
3235 	struct in_str input;
3236 #ifdef __U_BOOT__
3237 	char *p = NULL;
3238 	int rcode;
3239 	if (!s)
3240 		return 1;
3241 	if (!*s)
3242 		return 0;
3243 	if (!(p = strchr(s, '\n')) || *++p) {
3244 		p = xmalloc(strlen(s) + 2);
3245 		strcpy(p, s);
3246 		strcat(p, "\n");
3247 		setup_string_in_str(&input, p);
3248 		rcode = parse_stream_outer(&input, flag);
3249 		free(p);
3250 		return rcode;
3251 	} else {
3252 #endif
3253 	setup_string_in_str(&input, s);
3254 	return parse_stream_outer(&input, flag);
3255 #ifdef __U_BOOT__
3256 	}
3257 #endif
3258 }
3259 
3260 #ifndef __U_BOOT__
3261 static int parse_file_outer(FILE *f)
3262 #else
3263 int parse_file_outer(void)
3264 #endif
3265 {
3266 	int rcode;
3267 	struct in_str input;
3268 #ifndef __U_BOOT__
3269 	setup_file_in_str(&input, f);
3270 #else
3271 	setup_file_in_str(&input);
3272 #endif
3273 	rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
3274 	return rcode;
3275 }
3276 
3277 #ifdef __U_BOOT__
3278 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3279 static void u_boot_hush_reloc(void)
3280 {
3281 	unsigned long addr;
3282 	struct reserved_combo *r;
3283 
3284 	for (r=reserved_list; r<reserved_list+NRES; r++) {
3285 		addr = (ulong) (r->literal) + gd->reloc_off;
3286 		r->literal = (char *)addr;
3287 	}
3288 }
3289 #endif
3290 
3291 int u_boot_hush_start(void)
3292 {
3293 	if (top_vars == NULL) {
3294 		top_vars = malloc(sizeof(struct variables));
3295 		top_vars->name = "HUSH_VERSION";
3296 		top_vars->value = "0.01";
3297 		top_vars->next = NULL;
3298 		top_vars->flg_export = 0;
3299 		top_vars->flg_read_only = 1;
3300 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3301 		u_boot_hush_reloc();
3302 #endif
3303 	}
3304 	return 0;
3305 }
3306 
3307 static void *xmalloc(size_t size)
3308 {
3309 	void *p = NULL;
3310 
3311 	if (!(p = malloc(size))) {
3312 	    printf("ERROR : memory not allocated\n");
3313 	    for(;;);
3314 	}
3315 	return p;
3316 }
3317 
3318 static void *xrealloc(void *ptr, size_t size)
3319 {
3320 	void *p = NULL;
3321 
3322 	if (!(p = realloc(ptr, size))) {
3323 	    printf("ERROR : memory not allocated\n");
3324 	    for(;;);
3325 	}
3326 	return p;
3327 }
3328 #endif /* __U_BOOT__ */
3329 
3330 #ifndef __U_BOOT__
3331 /* Make sure we have a controlling tty.  If we get started under a job
3332  * aware app (like bash for example), make sure we are now in charge so
3333  * we don't fight over who gets the foreground */
3334 static void setup_job_control(void)
3335 {
3336 	static pid_t shell_pgrp;
3337 	/* Loop until we are in the foreground.  */
3338 	while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
3339 		kill (- shell_pgrp, SIGTTIN);
3340 
3341 	/* Ignore interactive and job-control signals.  */
3342 	signal(SIGINT, SIG_IGN);
3343 	signal(SIGQUIT, SIG_IGN);
3344 	signal(SIGTERM, SIG_IGN);
3345 	signal(SIGTSTP, SIG_IGN);
3346 	signal(SIGTTIN, SIG_IGN);
3347 	signal(SIGTTOU, SIG_IGN);
3348 	signal(SIGCHLD, SIG_IGN);
3349 
3350 	/* Put ourselves in our own process group.  */
3351 	setsid();
3352 	shell_pgrp = getpid ();
3353 	setpgid (shell_pgrp, shell_pgrp);
3354 
3355 	/* Grab control of the terminal.  */
3356 	tcsetpgrp(shell_terminal, shell_pgrp);
3357 }
3358 
3359 int hush_main(int argc, char * const *argv)
3360 {
3361 	int opt;
3362 	FILE *input;
3363 	char **e = environ;
3364 
3365 	/* XXX what should these be while sourcing /etc/profile? */
3366 	global_argc = argc;
3367 	global_argv = argv;
3368 
3369 	/* (re?) initialize globals.  Sometimes hush_main() ends up calling
3370 	 * hush_main(), therefore we cannot rely on the BSS to zero out this
3371 	 * stuff.  Reset these to 0 every time. */
3372 	ifs = NULL;
3373 	/* map[] is taken care of with call to update_ifs_map() */
3374 	fake_mode = 0;
3375 	interactive = 0;
3376 	close_me_head = NULL;
3377 	last_bg_pid = 0;
3378 	job_list = NULL;
3379 	last_jobid = 0;
3380 
3381 	/* Initialize some more globals to non-zero values */
3382 	set_cwd();
3383 #ifdef CONFIG_FEATURE_COMMAND_EDITING
3384 	cmdedit_set_initial_prompt();
3385 #else
3386 	PS1 = NULL;
3387 #endif
3388 	PS2 = "> ";
3389 
3390 	/* initialize our shell local variables with the values
3391 	 * currently living in the environment */
3392 	if (e) {
3393 		for (; *e; e++)
3394 			set_local_var(*e, 2);   /* without call putenv() */
3395 	}
3396 
3397 	last_return_code=EXIT_SUCCESS;
3398 
3399 
3400 	if (argv[0] && argv[0][0] == '-') {
3401 		debug_printf("\nsourcing /etc/profile\n");
3402 		if ((input = fopen("/etc/profile", "r")) != NULL) {
3403 			mark_open(fileno(input));
3404 			parse_file_outer(input);
3405 			mark_closed(fileno(input));
3406 			fclose(input);
3407 		}
3408 	}
3409 	input=stdin;
3410 
3411 	while ((opt = getopt(argc, argv, "c:xif")) > 0) {
3412 		switch (opt) {
3413 			case 'c':
3414 				{
3415 					global_argv = argv+optind;
3416 					global_argc = argc-optind;
3417 					opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
3418 					goto final_return;
3419 				}
3420 				break;
3421 			case 'i':
3422 				interactive++;
3423 				break;
3424 			case 'f':
3425 				fake_mode++;
3426 				break;
3427 			default:
3428 #ifndef BB_VER
3429 				fprintf(stderr, "Usage: sh [FILE]...\n"
3430 						"   or: sh -c command [args]...\n\n");
3431 				exit(EXIT_FAILURE);
3432 #else
3433 				show_usage();
3434 #endif
3435 		}
3436 	}
3437 	/* A shell is interactive if the `-i' flag was given, or if all of
3438 	 * the following conditions are met:
3439 	 *	  no -c command
3440 	 *    no arguments remaining or the -s flag given
3441 	 *    standard input is a terminal
3442 	 *    standard output is a terminal
3443 	 *    Refer to Posix.2, the description of the `sh' utility. */
3444 	if (argv[optind]==NULL && input==stdin &&
3445 			isatty(fileno(stdin)) && isatty(fileno(stdout))) {
3446 		interactive++;
3447 	}
3448 
3449 	debug_printf("\ninteractive=%d\n", interactive);
3450 	if (interactive) {
3451 		/* Looks like they want an interactive shell */
3452 #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
3453 		printf( "\n\n" BB_BANNER " hush - the humble shell v0.01 (testing)\n");
3454 		printf( "Enter 'help' for a list of built-in commands.\n\n");
3455 #endif
3456 		setup_job_control();
3457 	}
3458 
3459 	if (argv[optind]==NULL) {
3460 		opt=parse_file_outer(stdin);
3461 		goto final_return;
3462 	}
3463 
3464 	debug_printf("\nrunning script '%s'\n", argv[optind]);
3465 	global_argv = argv+optind;
3466 	global_argc = argc-optind;
3467 	input = xfopen(argv[optind], "r");
3468 	opt = parse_file_outer(input);
3469 
3470 #ifdef CONFIG_FEATURE_CLEAN_UP
3471 	fclose(input);
3472 	if (cwd && cwd != unknown)
3473 		free((char*)cwd);
3474 	{
3475 		struct variables *cur, *tmp;
3476 		for(cur = top_vars; cur; cur = tmp) {
3477 			tmp = cur->next;
3478 			if (!cur->flg_read_only) {
3479 				free(cur->name);
3480 				free(cur->value);
3481 				free(cur);
3482 			}
3483 		}
3484 	}
3485 #endif
3486 
3487 final_return:
3488 	return(opt?opt:last_return_code);
3489 }
3490 #endif
3491 
3492 static char *insert_var_value(char *inp)
3493 {
3494 	return insert_var_value_sub(inp, 0);
3495 }
3496 
3497 static char *insert_var_value_sub(char *inp, int tag_subst)
3498 {
3499 	int res_str_len = 0;
3500 	int len;
3501 	int done = 0;
3502 	char *p, *p1, *res_str = NULL;
3503 
3504 	while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
3505 		/* check the beginning of the string for normal charachters */
3506 		if (p != inp) {
3507 			/* copy any charachters to the result string */
3508 			len = p - inp;
3509 			res_str = xrealloc(res_str, (res_str_len + len));
3510 			strncpy((res_str + res_str_len), inp, len);
3511 			res_str_len += len;
3512 		}
3513 		inp = ++p;
3514 		/* find the ending marker */
3515 		p = strchr(inp, SPECIAL_VAR_SYMBOL);
3516 		*p = '\0';
3517 		/* look up the value to substitute */
3518 		if ((p1 = lookup_param(inp))) {
3519 			if (tag_subst)
3520 				len = res_str_len + strlen(p1) + 2;
3521 			else
3522 				len = res_str_len + strlen(p1);
3523 			res_str = xrealloc(res_str, (1 + len));
3524 			if (tag_subst) {
3525 				/*
3526 				 * copy the variable value to the result
3527 				 * string
3528 				 */
3529 				strcpy((res_str + res_str_len + 1), p1);
3530 
3531 				/*
3532 				 * mark the replaced text to be accepted as
3533 				 * is
3534 				 */
3535 				res_str[res_str_len] = SUBSTED_VAR_SYMBOL;
3536 				res_str[res_str_len + 1 + strlen(p1)] =
3537 					SUBSTED_VAR_SYMBOL;
3538 			} else
3539 				/*
3540 				 * copy the variable value to the result
3541 				 * string
3542 				 */
3543 				strcpy((res_str + res_str_len), p1);
3544 
3545 			res_str_len = len;
3546 		}
3547 		*p = SPECIAL_VAR_SYMBOL;
3548 		inp = ++p;
3549 		done = 1;
3550 	}
3551 	if (done) {
3552 		res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
3553 		strcpy((res_str + res_str_len), inp);
3554 		while ((p = strchr(res_str, '\n'))) {
3555 			*p = ' ';
3556 		}
3557 	}
3558 	return (res_str == NULL) ? inp : res_str;
3559 }
3560 
3561 static char **make_list_in(char **inp, char *name)
3562 {
3563 	int len, i;
3564 	int name_len = strlen(name);
3565 	int n = 0;
3566 	char **list;
3567 	char *p1, *p2, *p3;
3568 
3569 	/* create list of variable values */
3570 	list = xmalloc(sizeof(*list));
3571 	for (i = 0; inp[i]; i++) {
3572 		p3 = insert_var_value(inp[i]);
3573 		p1 = p3;
3574 		while (*p1) {
3575 			if (*p1 == ' ') {
3576 				p1++;
3577 				continue;
3578 			}
3579 			if ((p2 = strchr(p1, ' '))) {
3580 				len = p2 - p1;
3581 			} else {
3582 				len = strlen(p1);
3583 				p2 = p1 + len;
3584 			}
3585 			/* we use n + 2 in realloc for list,because we add
3586 			 * new element and then we will add NULL element */
3587 			list = xrealloc(list, sizeof(*list) * (n + 2));
3588 			list[n] = xmalloc(2 + name_len + len);
3589 			strcpy(list[n], name);
3590 			strcat(list[n], "=");
3591 			strncat(list[n], p1, len);
3592 			list[n++][name_len + len + 1] = '\0';
3593 			p1 = p2;
3594 		}
3595 		if (p3 != inp[i]) free(p3);
3596 	}
3597 	list[n] = NULL;
3598 	return list;
3599 }
3600 
3601 /*
3602  * Make new string for parser
3603  * inp     - array of argument strings to flatten
3604  * nonnull - indicates argument was quoted when originally parsed
3605  */
3606 static char *make_string(char **inp, int *nonnull)
3607 {
3608 	char *p;
3609 	char *str = NULL;
3610 	int n;
3611 	int len = 2;
3612 	char *noeval_str;
3613 	int noeval = 0;
3614 
3615 	noeval_str = get_local_var("HUSH_NO_EVAL");
3616 	if (noeval_str != NULL && *noeval_str != '0' && *noeval_str != '\0')
3617 		noeval = 1;
3618 	for (n = 0; inp[n]; n++) {
3619 		p = insert_var_value_sub(inp[n], noeval);
3620 		str = xrealloc(str, (len + strlen(p) + (2 * nonnull[n])));
3621 		if (n) {
3622 			strcat(str, " ");
3623 		} else {
3624 			*str = '\0';
3625 		}
3626 		if (nonnull[n])
3627 			strcat(str, "'");
3628 		strcat(str, p);
3629 		if (nonnull[n])
3630 			strcat(str, "'");
3631 		len = strlen(str) + 3;
3632 		if (p != inp[n]) free(p);
3633 	}
3634 	len = strlen(str);
3635 	*(str + len) = '\n';
3636 	*(str + len + 1) = '\0';
3637 	return str;
3638 }
3639 
3640 #ifdef __U_BOOT__
3641 static int do_showvar(cmd_tbl_t *cmdtp, int flag, int argc,
3642 		      char * const argv[])
3643 {
3644 	int i, k;
3645 	int rcode = 0;
3646 	struct variables *cur;
3647 
3648 	if (argc == 1) {		/* Print all env variables	*/
3649 		for (cur = top_vars; cur; cur = cur->next) {
3650 			printf ("%s=%s\n", cur->name, cur->value);
3651 			if (ctrlc ()) {
3652 				puts ("\n ** Abort\n");
3653 				return 1;
3654 			}
3655 		}
3656 		return 0;
3657 	}
3658 	for (i = 1; i < argc; ++i) {	/* print single env variables	*/
3659 		char *name = argv[i];
3660 
3661 		k = -1;
3662 		for (cur = top_vars; cur; cur = cur->next) {
3663 			if(strcmp (cur->name, name) == 0) {
3664 				k = 0;
3665 				printf ("%s=%s\n", cur->name, cur->value);
3666 			}
3667 			if (ctrlc ()) {
3668 				puts ("\n ** Abort\n");
3669 				return 1;
3670 			}
3671 		}
3672 		if (k < 0) {
3673 			printf ("## Error: \"%s\" not defined\n", name);
3674 			rcode ++;
3675 		}
3676 	}
3677 	return rcode;
3678 }
3679 
3680 U_BOOT_CMD(
3681 	showvar, CONFIG_SYS_MAXARGS, 1,	do_showvar,
3682 	"print local hushshell variables",
3683 	"\n    - print values of all hushshell variables\n"
3684 	"showvar name ...\n"
3685 	"    - print value of hushshell variable 'name'"
3686 );
3687 
3688 #endif
3689 /****************************************************************************/
3690