xref: /rk3399_rockchip-uboot/common/cli_hush.c (revision 13d3046fa392625f172d55cba8eb551f47e45f3f)
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 <console.h>
83 #include <bootretry.h>
84 #include <cli.h>
85 #include <cli_hush.h>
86 #include <command.h>        /* find_cmd */
87 #ifndef CONFIG_SYS_PROMPT_HUSH_PS2
88 #define CONFIG_SYS_PROMPT_HUSH_PS2	"> "
89 #endif
90 #endif
91 #ifndef __U_BOOT__
92 #include <ctype.h>     /* isalpha, isdigit */
93 #include <unistd.h>    /* getpid */
94 #include <stdlib.h>    /* getenv, atoi */
95 #include <string.h>    /* strchr */
96 #include <stdio.h>     /* popen etc. */
97 #include <glob.h>      /* glob, of course */
98 #include <stdarg.h>    /* va_list */
99 #include <errno.h>
100 #include <fcntl.h>
101 #include <getopt.h>    /* should be pretty obvious */
102 
103 #include <sys/stat.h>  /* ulimit */
104 #include <sys/types.h>
105 #include <sys/wait.h>
106 #include <signal.h>
107 
108 /* #include <dmalloc.h> */
109 
110 #if 1
111 #include "busybox.h"
112 #include "cmdedit.h"
113 #else
114 #define applet_name "hush"
115 #include "standalone.h"
116 #define hush_main main
117 #undef CONFIG_FEATURE_SH_FANCY_PROMPT
118 #define BB_BANNER
119 #endif
120 #endif
121 #define SPECIAL_VAR_SYMBOL 03
122 #define SUBSTED_VAR_SYMBOL 04
123 #ifndef __U_BOOT__
124 #define FLAG_EXIT_FROM_LOOP 1
125 #define FLAG_PARSE_SEMICOLON (1 << 1)		/* symbol ';' is special for parser */
126 #define FLAG_REPARSING       (1 << 2)		/* >= 2nd pass */
127 
128 #endif
129 
130 #ifdef __U_BOOT__
131 DECLARE_GLOBAL_DATA_PTR;
132 
133 #define EXIT_SUCCESS 0
134 #define EOF -1
135 #define syntax() syntax_err()
136 #define xstrdup strdup
137 #define error_msg printf
138 #else
139 typedef enum {
140 	REDIRECT_INPUT     = 1,
141 	REDIRECT_OVERWRITE = 2,
142 	REDIRECT_APPEND    = 3,
143 	REDIRECT_HEREIS    = 4,
144 	REDIRECT_IO        = 5
145 } redir_type;
146 
147 /* The descrip member of this structure is only used to make debugging
148  * output pretty */
149 struct {int mode; int default_fd; char *descrip;} redir_table[] = {
150 	{ 0,                         0, "()" },
151 	{ O_RDONLY,                  0, "<"  },
152 	{ O_CREAT|O_TRUNC|O_WRONLY,  1, ">"  },
153 	{ O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
154 	{ O_RDONLY,                 -1, "<<" },
155 	{ O_RDWR,                    1, "<>" }
156 };
157 #endif
158 
159 typedef enum {
160 	PIPE_SEQ = 1,
161 	PIPE_AND = 2,
162 	PIPE_OR  = 3,
163 	PIPE_BG  = 4,
164 } pipe_style;
165 
166 /* might eventually control execution */
167 typedef enum {
168 	RES_NONE  = 0,
169 	RES_IF    = 1,
170 	RES_THEN  = 2,
171 	RES_ELIF  = 3,
172 	RES_ELSE  = 4,
173 	RES_FI    = 5,
174 	RES_FOR   = 6,
175 	RES_WHILE = 7,
176 	RES_UNTIL = 8,
177 	RES_DO    = 9,
178 	RES_DONE  = 10,
179 	RES_XXXX  = 11,
180 	RES_IN    = 12,
181 	RES_SNTX  = 13
182 } reserved_style;
183 #define FLAG_END   (1<<RES_NONE)
184 #define FLAG_IF    (1<<RES_IF)
185 #define FLAG_THEN  (1<<RES_THEN)
186 #define FLAG_ELIF  (1<<RES_ELIF)
187 #define FLAG_ELSE  (1<<RES_ELSE)
188 #define FLAG_FI    (1<<RES_FI)
189 #define FLAG_FOR   (1<<RES_FOR)
190 #define FLAG_WHILE (1<<RES_WHILE)
191 #define FLAG_UNTIL (1<<RES_UNTIL)
192 #define FLAG_DO    (1<<RES_DO)
193 #define FLAG_DONE  (1<<RES_DONE)
194 #define FLAG_IN    (1<<RES_IN)
195 #define FLAG_START (1<<RES_XXXX)
196 
197 /* This holds pointers to the various results of parsing */
198 struct p_context {
199 	struct child_prog *child;
200 	struct pipe *list_head;
201 	struct pipe *pipe;
202 #ifndef __U_BOOT__
203 	struct redir_struct *pending_redirect;
204 #endif
205 	reserved_style w;
206 	int old_flag;				/* for figuring out valid reserved words */
207 	struct p_context *stack;
208 	int type;			/* define type of parser : ";$" common or special symbol */
209 	/* How about quoting status? */
210 };
211 
212 #ifndef __U_BOOT__
213 struct redir_struct {
214 	redir_type type;			/* type of redirection */
215 	int fd;						/* file descriptor being redirected */
216 	int dup;					/* -1, or file descriptor being duplicated */
217 	struct redir_struct *next;	/* pointer to the next redirect in the list */
218 	glob_t word;				/* *word.gl_pathv is the filename */
219 };
220 #endif
221 
222 struct child_prog {
223 #ifndef __U_BOOT__
224 	pid_t pid;					/* 0 if exited */
225 #endif
226 	char **argv;				/* program name and arguments */
227 	/* was quoted when parsed; copy of struct o_string.nonnull field */
228 	int *argv_nonnull;
229 #ifdef __U_BOOT__
230 	int    argc;                            /* number of program arguments */
231 #endif
232 	struct pipe *group;			/* if non-NULL, first in group or subshell */
233 #ifndef __U_BOOT__
234 	int subshell;				/* flag, non-zero if group must be forked */
235 	struct redir_struct *redirects;	/* I/O redirections */
236 	glob_t glob_result;			/* result of parameter globbing */
237 	int is_stopped;				/* is the program currently running? */
238 	struct pipe *family;		/* pointer back to the child's parent pipe */
239 #endif
240 	int sp;				/* number of SPECIAL_VAR_SYMBOL */
241 	int type;
242 };
243 
244 struct pipe {
245 #ifndef __U_BOOT__
246 	int jobid;					/* job number */
247 #endif
248 	int num_progs;				/* total number of programs in job */
249 #ifndef __U_BOOT__
250 	int running_progs;			/* number of programs running */
251 	char *text;					/* name of job */
252 	char *cmdbuf;				/* buffer various argv's point into */
253 	pid_t pgrp;					/* process group ID for the job */
254 #endif
255 	struct child_prog *progs;	/* array of commands in pipe */
256 	struct pipe *next;			/* to track background commands */
257 #ifndef __U_BOOT__
258 	int stopped_progs;			/* number of programs alive, but stopped */
259 	int job_context;			/* bitmask defining current context */
260 #endif
261 	pipe_style followup;		/* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
262 	reserved_style r_mode;		/* supports if, for, while, until */
263 };
264 
265 #ifndef __U_BOOT__
266 struct close_me {
267 	int fd;
268 	struct close_me *next;
269 };
270 #endif
271 
272 struct variables {
273 	char *name;
274 	char *value;
275 	int flg_export;
276 	int flg_read_only;
277 	struct variables *next;
278 };
279 
280 /* globals, connect us to the outside world
281  * the first three support $?, $#, and $1 */
282 #ifndef __U_BOOT__
283 char **global_argv;
284 unsigned int global_argc;
285 #endif
286 static unsigned int last_return_code;
287 #ifndef __U_BOOT__
288 extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
289 #endif
290 
291 /* "globals" within this file */
292 static uchar *ifs;
293 static char map[256];
294 #ifndef __U_BOOT__
295 static int fake_mode;
296 static int interactive;
297 static struct close_me *close_me_head;
298 static const char *cwd;
299 static struct pipe *job_list;
300 static unsigned int last_bg_pid;
301 static unsigned int last_jobid;
302 static unsigned int shell_terminal;
303 static char *PS1;
304 static char *PS2;
305 struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
306 struct variables *top_vars = &shell_ver;
307 #else
308 static int flag_repeat = 0;
309 static int do_repeat = 0;
310 static struct variables *top_vars = NULL ;
311 #endif /*__U_BOOT__ */
312 
313 #define B_CHUNK (100)
314 #define B_NOSPAC 1
315 
316 typedef struct {
317 	char *data;
318 	int length;
319 	int maxlen;
320 	int quote;
321 	int nonnull;
322 } o_string;
323 #define NULL_O_STRING {NULL,0,0,0,0}
324 /* used for initialization:
325 	o_string foo = NULL_O_STRING; */
326 
327 /* I can almost use ordinary FILE *.  Is open_memstream() universally
328  * available?  Where is it documented? */
329 struct in_str {
330 	const char *p;
331 #ifndef __U_BOOT__
332 	char peek_buf[2];
333 #endif
334 	int __promptme;
335 	int promptmode;
336 #ifndef __U_BOOT__
337 	FILE *file;
338 #endif
339 	int (*get) (struct in_str *);
340 	int (*peek) (struct in_str *);
341 };
342 #define b_getch(input) ((input)->get(input))
343 #define b_peek(input) ((input)->peek(input))
344 
345 #ifndef __U_BOOT__
346 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
347 
348 struct built_in_command {
349 	char *cmd;					/* name */
350 	char *descr;				/* description */
351 	int (*function) (struct child_prog *);	/* function ptr */
352 };
353 #endif
354 
355 /* define DEBUG_SHELL for debugging output (obviously ;-)) */
356 #if 0
357 #define DEBUG_SHELL
358 #endif
359 
360 /* This should be in utility.c */
361 #ifdef DEBUG_SHELL
362 #ifndef __U_BOOT__
363 static void debug_printf(const char *format, ...)
364 {
365 	va_list args;
366 	va_start(args, format);
367 	vfprintf(stderr, format, args);
368 	va_end(args);
369 }
370 #else
371 #define debug_printf(fmt,args...)	printf (fmt ,##args)
372 #endif
373 #else
374 static inline void debug_printf(const char *format, ...) { }
375 #endif
376 #define final_printf debug_printf
377 
378 #ifdef __U_BOOT__
379 static void syntax_err(void) {
380 	 printf("syntax error\n");
381 }
382 #else
383 static void __syntax(char *file, int line) {
384 	error_msg("syntax error %s:%d", file, line);
385 }
386 #define syntax() __syntax(__FILE__, __LINE__)
387 #endif
388 
389 #ifdef __U_BOOT__
390 static void *xmalloc(size_t size);
391 static void *xrealloc(void *ptr, size_t size);
392 #else
393 /* Index of subroutines: */
394 /*   function prototypes for builtins */
395 static int builtin_cd(struct child_prog *child);
396 static int builtin_env(struct child_prog *child);
397 static int builtin_eval(struct child_prog *child);
398 static int builtin_exec(struct child_prog *child);
399 static int builtin_exit(struct child_prog *child);
400 static int builtin_export(struct child_prog *child);
401 static int builtin_fg_bg(struct child_prog *child);
402 static int builtin_help(struct child_prog *child);
403 static int builtin_jobs(struct child_prog *child);
404 static int builtin_pwd(struct child_prog *child);
405 static int builtin_read(struct child_prog *child);
406 static int builtin_set(struct child_prog *child);
407 static int builtin_shift(struct child_prog *child);
408 static int builtin_source(struct child_prog *child);
409 static int builtin_umask(struct child_prog *child);
410 static int builtin_unset(struct child_prog *child);
411 static int builtin_not_written(struct child_prog *child);
412 #endif
413 /*   o_string manipulation: */
414 static int b_check_space(o_string *o, int len);
415 static int b_addchr(o_string *o, int ch);
416 static void b_reset(o_string *o);
417 static int b_addqchr(o_string *o, int ch, int quote);
418 #ifndef __U_BOOT__
419 static int b_adduint(o_string *o, unsigned int i);
420 #endif
421 /*  in_str manipulations: */
422 static int static_get(struct in_str *i);
423 static int static_peek(struct in_str *i);
424 static int file_get(struct in_str *i);
425 static int file_peek(struct in_str *i);
426 #ifndef __U_BOOT__
427 static void setup_file_in_str(struct in_str *i, FILE *f);
428 #else
429 static void setup_file_in_str(struct in_str *i);
430 #endif
431 static void setup_string_in_str(struct in_str *i, const char *s);
432 #ifndef __U_BOOT__
433 /*  close_me manipulations: */
434 static void mark_open(int fd);
435 static void mark_closed(int fd);
436 static void close_all(void);
437 #endif
438 /*  "run" the final data structures: */
439 static char *indenter(int i);
440 static int free_pipe_list(struct pipe *head, int indent);
441 static int free_pipe(struct pipe *pi, int indent);
442 /*  really run the final data structures: */
443 #ifndef __U_BOOT__
444 static int setup_redirects(struct child_prog *prog, int squirrel[]);
445 #endif
446 static int run_list_real(struct pipe *pi);
447 #ifndef __U_BOOT__
448 static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
449 #endif
450 static int run_pipe_real(struct pipe *pi);
451 /*   extended glob support: */
452 #ifndef __U_BOOT__
453 static int globhack(const char *src, int flags, glob_t *pglob);
454 static int glob_needed(const char *s);
455 static int xglob(o_string *dest, int flags, glob_t *pglob);
456 #endif
457 /*   variable assignment: */
458 static int is_assignment(const char *s);
459 /*   data structure manipulation: */
460 #ifndef __U_BOOT__
461 static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
462 #endif
463 static void initialize_context(struct p_context *ctx);
464 static int done_word(o_string *dest, struct p_context *ctx);
465 static int done_command(struct p_context *ctx);
466 static int done_pipe(struct p_context *ctx, pipe_style type);
467 /*   primary string parsing: */
468 #ifndef __U_BOOT__
469 static int redirect_dup_num(struct in_str *input);
470 static int redirect_opt_num(o_string *o);
471 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
472 static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
473 #endif
474 static char *lookup_param(char *src);
475 static char *make_string(char **inp, int *nonnull);
476 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
477 #ifndef __U_BOOT__
478 static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
479 #endif
480 static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
481 /*   setup: */
482 static int parse_stream_outer(struct in_str *inp, int flag);
483 #ifndef __U_BOOT__
484 static int parse_string_outer(const char *s, int flag);
485 static int parse_file_outer(FILE *f);
486 #endif
487 #ifndef __U_BOOT__
488 /*   job management: */
489 static int checkjobs(struct pipe* fg_pipe);
490 static void insert_bg_job(struct pipe *pi);
491 static void remove_bg_job(struct pipe *pi);
492 #endif
493 /*     local variable support */
494 static char **make_list_in(char **inp, char *name);
495 static char *insert_var_value(char *inp);
496 static char *insert_var_value_sub(char *inp, int tag_subst);
497 
498 #ifndef __U_BOOT__
499 /* Table of built-in functions.  They can be forked or not, depending on
500  * context: within pipes, they fork.  As simple commands, they do not.
501  * When used in non-forking context, they can change global variables
502  * in the parent shell process.  If forked, of course they can not.
503  * For example, 'unset foo | whatever' will parse and run, but foo will
504  * still be set at the end. */
505 static struct built_in_command bltins[] = {
506 	{"bg", "Resume a job in the background", builtin_fg_bg},
507 	{"break", "Exit for, while or until loop", builtin_not_written},
508 	{"cd", "Change working directory", builtin_cd},
509 	{"continue", "Continue for, while or until loop", builtin_not_written},
510 	{"env", "Print all environment variables", builtin_env},
511 	{"eval", "Construct and run shell command", builtin_eval},
512 	{"exec", "Exec command, replacing this shell with the exec'd process",
513 		builtin_exec},
514 	{"exit", "Exit from shell()", builtin_exit},
515 	{"export", "Set environment variable", builtin_export},
516 	{"fg", "Bring job into the foreground", builtin_fg_bg},
517 	{"jobs", "Lists the active jobs", builtin_jobs},
518 	{"pwd", "Print current directory", builtin_pwd},
519 	{"read", "Input environment variable", builtin_read},
520 	{"return", "Return from a function", builtin_not_written},
521 	{"set", "Set/unset shell local variables", builtin_set},
522 	{"shift", "Shift positional parameters", builtin_shift},
523 	{"trap", "Trap signals", builtin_not_written},
524 	{"ulimit","Controls resource limits", builtin_not_written},
525 	{"umask","Sets file creation mask", builtin_umask},
526 	{"unset", "Unset environment variable", builtin_unset},
527 	{".", "Source-in and run commands in a file", builtin_source},
528 	{"help", "List shell built-in commands", builtin_help},
529 	{NULL, NULL, NULL}
530 };
531 
532 static const char *set_cwd(void)
533 {
534 	if(cwd==unknown)
535 		cwd = NULL;     /* xgetcwd(arg) called free(arg) */
536 	cwd = xgetcwd((char *)cwd);
537 	if (!cwd)
538 		cwd = unknown;
539 	return cwd;
540 }
541 
542 /* built-in 'eval' handler */
543 static int builtin_eval(struct child_prog *child)
544 {
545 	char *str = NULL;
546 	int rcode = EXIT_SUCCESS;
547 
548 	if (child->argv[1]) {
549 		str = make_string(child->argv + 1);
550 		parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
551 					FLAG_PARSE_SEMICOLON);
552 		free(str);
553 		rcode = last_return_code;
554 	}
555 	return rcode;
556 }
557 
558 /* built-in 'cd <path>' handler */
559 static int builtin_cd(struct child_prog *child)
560 {
561 	char *newdir;
562 	if (child->argv[1] == NULL)
563 		newdir = getenv("HOME");
564 	else
565 		newdir = child->argv[1];
566 	if (chdir(newdir)) {
567 		printf("cd: %s: %s\n", newdir, strerror(errno));
568 		return EXIT_FAILURE;
569 	}
570 	set_cwd();
571 	return EXIT_SUCCESS;
572 }
573 
574 /* built-in 'env' handler */
575 static int builtin_env(struct child_prog *dummy)
576 {
577 	char **e = environ;
578 	if (e == NULL) return EXIT_FAILURE;
579 	for (; *e; e++) {
580 		puts(*e);
581 	}
582 	return EXIT_SUCCESS;
583 }
584 
585 /* built-in 'exec' handler */
586 static int builtin_exec(struct child_prog *child)
587 {
588 	if (child->argv[1] == NULL)
589 		return EXIT_SUCCESS;   /* Really? */
590 	child->argv++;
591 	pseudo_exec(child);
592 	/* never returns */
593 }
594 
595 /* built-in 'exit' handler */
596 static int builtin_exit(struct child_prog *child)
597 {
598 	if (child->argv[1] == NULL)
599 		exit(last_return_code);
600 	exit (atoi(child->argv[1]));
601 }
602 
603 /* built-in 'export VAR=value' handler */
604 static int builtin_export(struct child_prog *child)
605 {
606 	int res = 0;
607 	char *name = child->argv[1];
608 
609 	if (name == NULL) {
610 		return (builtin_env(child));
611 	}
612 
613 	name = strdup(name);
614 
615 	if(name) {
616 		char *value = strchr(name, '=');
617 
618 		if (!value) {
619 			char *tmp;
620 			/* They are exporting something without an =VALUE */
621 
622 			value = get_local_var(name);
623 			if (value) {
624 				size_t ln = strlen(name);
625 
626 				tmp = realloc(name, ln+strlen(value)+2);
627 				if(tmp==NULL)
628 					res = -1;
629 				else {
630 					sprintf(tmp+ln, "=%s", value);
631 					name = tmp;
632 				}
633 			} else {
634 				/* bash does not return an error when trying to export
635 				 * an undefined variable.  Do likewise. */
636 				res = 1;
637 			}
638 		}
639 	}
640 	if (res<0)
641 		perror_msg("export");
642 	else if(res==0)
643 		res = set_local_var(name, 1);
644 	else
645 		res = 0;
646 	free(name);
647 	return res;
648 }
649 
650 /* built-in 'fg' and 'bg' handler */
651 static int builtin_fg_bg(struct child_prog *child)
652 {
653 	int i, jobnum;
654 	struct pipe *pi=NULL;
655 
656 	if (!interactive)
657 		return EXIT_FAILURE;
658 	/* If they gave us no args, assume they want the last backgrounded task */
659 	if (!child->argv[1]) {
660 		for (pi = job_list; pi; pi = pi->next) {
661 			if (pi->jobid == last_jobid) {
662 				break;
663 			}
664 		}
665 		if (!pi) {
666 			error_msg("%s: no current job", child->argv[0]);
667 			return EXIT_FAILURE;
668 		}
669 	} else {
670 		if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
671 			error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
672 			return EXIT_FAILURE;
673 		}
674 		for (pi = job_list; pi; pi = pi->next) {
675 			if (pi->jobid == jobnum) {
676 				break;
677 			}
678 		}
679 		if (!pi) {
680 			error_msg("%s: %d: no such job", child->argv[0], jobnum);
681 			return EXIT_FAILURE;
682 		}
683 	}
684 
685 	if (*child->argv[0] == 'f') {
686 		/* Put the job into the foreground.  */
687 		tcsetpgrp(shell_terminal, pi->pgrp);
688 	}
689 
690 	/* Restart the processes in the job */
691 	for (i = 0; i < pi->num_progs; i++)
692 		pi->progs[i].is_stopped = 0;
693 
694 	if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) {
695 		if (i == ESRCH) {
696 			remove_bg_job(pi);
697 		} else {
698 			perror_msg("kill (SIGCONT)");
699 		}
700 	}
701 
702 	pi->stopped_progs = 0;
703 	return EXIT_SUCCESS;
704 }
705 
706 /* built-in 'help' handler */
707 static int builtin_help(struct child_prog *dummy)
708 {
709 	struct built_in_command *x;
710 
711 	printf("\nBuilt-in commands:\n");
712 	printf("-------------------\n");
713 	for (x = bltins; x->cmd; x++) {
714 		if (x->descr==NULL)
715 			continue;
716 		printf("%s\t%s\n", x->cmd, x->descr);
717 	}
718 	printf("\n\n");
719 	return EXIT_SUCCESS;
720 }
721 
722 /* built-in 'jobs' handler */
723 static int builtin_jobs(struct child_prog *child)
724 {
725 	struct pipe *job;
726 	char *status_string;
727 
728 	for (job = job_list; job; job = job->next) {
729 		if (job->running_progs == job->stopped_progs)
730 			status_string = "Stopped";
731 		else
732 			status_string = "Running";
733 
734 		printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
735 	}
736 	return EXIT_SUCCESS;
737 }
738 
739 
740 /* built-in 'pwd' handler */
741 static int builtin_pwd(struct child_prog *dummy)
742 {
743 	puts(set_cwd());
744 	return EXIT_SUCCESS;
745 }
746 
747 /* built-in 'read VAR' handler */
748 static int builtin_read(struct child_prog *child)
749 {
750 	int res;
751 
752 	if (child->argv[1]) {
753 		char string[BUFSIZ];
754 		char *var = 0;
755 
756 		string[0] = 0;  /* In case stdin has only EOF */
757 		/* read string */
758 		fgets(string, sizeof(string), stdin);
759 		chomp(string);
760 		var = malloc(strlen(child->argv[1])+strlen(string)+2);
761 		if(var) {
762 			sprintf(var, "%s=%s", child->argv[1], string);
763 			res = set_local_var(var, 0);
764 		} else
765 			res = -1;
766 		if (res)
767 			fprintf(stderr, "read: %m\n");
768 		free(var);      /* So not move up to avoid breaking errno */
769 		return res;
770 	} else {
771 		do res=getchar(); while(res!='\n' && res!=EOF);
772 		return 0;
773 	}
774 }
775 
776 /* built-in 'set VAR=value' handler */
777 static int builtin_set(struct child_prog *child)
778 {
779 	char *temp = child->argv[1];
780 	struct variables *e;
781 
782 	if (temp == NULL)
783 		for(e = top_vars; e; e=e->next)
784 			printf("%s=%s\n", e->name, e->value);
785 	else
786 		set_local_var(temp, 0);
787 
788 		return EXIT_SUCCESS;
789 }
790 
791 
792 /* Built-in 'shift' handler */
793 static int builtin_shift(struct child_prog *child)
794 {
795 	int n=1;
796 	if (child->argv[1]) {
797 		n=atoi(child->argv[1]);
798 	}
799 	if (n>=0 && n<global_argc) {
800 		/* XXX This probably breaks $0 */
801 		global_argc -= n;
802 		global_argv += n;
803 		return EXIT_SUCCESS;
804 	} else {
805 		return EXIT_FAILURE;
806 	}
807 }
808 
809 /* Built-in '.' handler (read-in and execute commands from file) */
810 static int builtin_source(struct child_prog *child)
811 {
812 	FILE *input;
813 	int status;
814 
815 	if (child->argv[1] == NULL)
816 		return EXIT_FAILURE;
817 
818 	/* XXX search through $PATH is missing */
819 	input = fopen(child->argv[1], "r");
820 	if (!input) {
821 		error_msg("Couldn't open file '%s'", child->argv[1]);
822 		return EXIT_FAILURE;
823 	}
824 
825 	/* Now run the file */
826 	/* XXX argv and argc are broken; need to save old global_argv
827 	 * (pointer only is OK!) on this stack frame,
828 	 * set global_argv=child->argv+1, recurse, and restore. */
829 	mark_open(fileno(input));
830 	status = parse_file_outer(input);
831 	mark_closed(fileno(input));
832 	fclose(input);
833 	return (status);
834 }
835 
836 static int builtin_umask(struct child_prog *child)
837 {
838 	mode_t new_umask;
839 	const char *arg = child->argv[1];
840 	char *end;
841 	if (arg) {
842 		new_umask=strtoul(arg, &end, 8);
843 		if (*end!='\0' || end == arg) {
844 			return EXIT_FAILURE;
845 		}
846 	} else {
847 		printf("%.3o\n", (unsigned int) (new_umask=umask(0)));
848 	}
849 	umask(new_umask);
850 	return EXIT_SUCCESS;
851 }
852 
853 /* built-in 'unset VAR' handler */
854 static int builtin_unset(struct child_prog *child)
855 {
856 	/* bash returned already true */
857 	unset_local_var(child->argv[1]);
858 	return EXIT_SUCCESS;
859 }
860 
861 static int builtin_not_written(struct child_prog *child)
862 {
863 	printf("builtin_%s not written\n",child->argv[0]);
864 	return EXIT_FAILURE;
865 }
866 #endif
867 
868 static int b_check_space(o_string *o, int len)
869 {
870 	/* It would be easy to drop a more restrictive policy
871 	 * in here, such as setting a maximum string length */
872 	if (o->length + len > o->maxlen) {
873 		char *old_data = o->data;
874 		/* assert (data == NULL || o->maxlen != 0); */
875 		o->maxlen += max(2*len, B_CHUNK);
876 		o->data = realloc(o->data, 1 + o->maxlen);
877 		if (o->data == NULL) {
878 			free(old_data);
879 		}
880 	}
881 	return o->data == NULL;
882 }
883 
884 static int b_addchr(o_string *o, int ch)
885 {
886 	debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
887 	if (b_check_space(o, 1)) return B_NOSPAC;
888 	o->data[o->length] = ch;
889 	o->length++;
890 	o->data[o->length] = '\0';
891 	return 0;
892 }
893 
894 static void b_reset(o_string *o)
895 {
896 	o->length = 0;
897 	o->nonnull = 0;
898 	if (o->data != NULL) *o->data = '\0';
899 }
900 
901 static void b_free(o_string *o)
902 {
903 	b_reset(o);
904 	free(o->data);
905 	o->data = NULL;
906 	o->maxlen = 0;
907 }
908 
909 /* My analysis of quoting semantics tells me that state information
910  * is associated with a destination, not a source.
911  */
912 static int b_addqchr(o_string *o, int ch, int quote)
913 {
914 	if (quote && strchr("*?[\\",ch)) {
915 		int rc;
916 		rc = b_addchr(o, '\\');
917 		if (rc) return rc;
918 	}
919 	return b_addchr(o, ch);
920 }
921 
922 #ifndef __U_BOOT__
923 static int b_adduint(o_string *o, unsigned int i)
924 {
925 	int r;
926 	char *p = simple_itoa(i);
927 	/* no escape checking necessary */
928 	do r=b_addchr(o, *p++); while (r==0 && *p);
929 	return r;
930 }
931 #endif
932 
933 static int static_get(struct in_str *i)
934 {
935 	int ch = *i->p++;
936 	if (ch=='\0') return EOF;
937 	return ch;
938 }
939 
940 static int static_peek(struct in_str *i)
941 {
942 	return *i->p;
943 }
944 
945 #ifndef __U_BOOT__
946 static inline void cmdedit_set_initial_prompt(void)
947 {
948 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
949 	PS1 = NULL;
950 #else
951 	PS1 = getenv("PS1");
952 	if(PS1==0)
953 		PS1 = "\\w \\$ ";
954 #endif
955 }
956 
957 static inline void setup_prompt_string(int promptmode, char **prompt_str)
958 {
959 	debug_printf("setup_prompt_string %d ",promptmode);
960 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
961 	/* Set up the prompt */
962 	if (promptmode == 1) {
963 		free(PS1);
964 		PS1=xmalloc(strlen(cwd)+4);
965 		sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ?  "$ ":"# ");
966 		*prompt_str = PS1;
967 	} else {
968 		*prompt_str = PS2;
969 	}
970 #else
971 	*prompt_str = (promptmode==1)? PS1 : PS2;
972 #endif
973 	debug_printf("result %s\n",*prompt_str);
974 }
975 #endif
976 
977 #ifdef __U_BOOT__
978 static int uboot_cli_readline(struct in_str *i)
979 {
980 	char *prompt;
981 
982 	if (i->promptmode == 1)
983 		prompt = CONFIG_SYS_PROMPT;
984 	else
985 		prompt = CONFIG_SYS_PROMPT_HUSH_PS2;
986 
987 	return cli_readline(prompt);
988 }
989 #endif
990 
991 static void get_user_input(struct in_str *i)
992 {
993 #ifndef __U_BOOT__
994 	char *prompt_str;
995 	static char the_command[BUFSIZ];
996 
997 	setup_prompt_string(i->promptmode, &prompt_str);
998 #ifdef CONFIG_FEATURE_COMMAND_EDITING
999 	/*
1000 	 ** enable command line editing only while a command line
1001 	 ** is actually being read; otherwise, we'll end up bequeathing
1002 	 ** atexit() handlers and other unwanted stuff to our
1003 	 ** child processes (rob@sysgo.de)
1004 	 */
1005 	cmdedit_read_input(prompt_str, the_command);
1006 #else
1007 	fputs(prompt_str, stdout);
1008 	fflush(stdout);
1009 	the_command[0]=fgetc(i->file);
1010 	the_command[1]='\0';
1011 #endif
1012 	fflush(stdout);
1013 	i->p = the_command;
1014 #else
1015 	int n;
1016 	static char the_command[CONFIG_SYS_CBSIZE + 1];
1017 
1018 	bootretry_reset_cmd_timeout();
1019 	i->__promptme = 1;
1020 	n = uboot_cli_readline(i);
1021 
1022 #ifdef CONFIG_BOOT_RETRY_TIME
1023 	if (n == -2) {
1024 	  puts("\nTimeout waiting for command\n");
1025 #  ifdef CONFIG_RESET_TO_RETRY
1026 	  do_reset(NULL, 0, 0, NULL);
1027 #  else
1028 #	error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1029 #  endif
1030 	}
1031 #endif
1032 	if (n == -1 ) {
1033 		flag_repeat = 0;
1034 		i->__promptme = 0;
1035 	}
1036 	n = strlen(console_buffer);
1037 	console_buffer[n] = '\n';
1038 	console_buffer[n+1]= '\0';
1039 	if (had_ctrlc()) flag_repeat = 0;
1040 	clear_ctrlc();
1041 	do_repeat = 0;
1042 	if (i->promptmode == 1) {
1043 		if (console_buffer[0] == '\n'&& flag_repeat == 0) {
1044 			strcpy(the_command,console_buffer);
1045 		}
1046 		else {
1047 			if (console_buffer[0] != '\n') {
1048 				strcpy(the_command,console_buffer);
1049 				flag_repeat = 1;
1050 			}
1051 			else {
1052 				do_repeat = 1;
1053 			}
1054 		}
1055 		i->p = the_command;
1056 	}
1057 	else {
1058 		if (console_buffer[0] != '\n') {
1059 			if (strlen(the_command) + strlen(console_buffer)
1060 			    < CONFIG_SYS_CBSIZE) {
1061 				n = strlen(the_command);
1062 				the_command[n-1] = ' ';
1063 				strcpy(&the_command[n],console_buffer);
1064 			}
1065 			else {
1066 				the_command[0] = '\n';
1067 				the_command[1] = '\0';
1068 				flag_repeat = 0;
1069 			}
1070 		}
1071 		if (i->__promptme == 0) {
1072 			the_command[0] = '\n';
1073 			the_command[1] = '\0';
1074 		}
1075 		i->p = console_buffer;
1076 	}
1077 #endif
1078 }
1079 
1080 /* This is the magic location that prints prompts
1081  * and gets data back from the user */
1082 static int file_get(struct in_str *i)
1083 {
1084 	int ch;
1085 
1086 	ch = 0;
1087 	/* If there is data waiting, eat it up */
1088 	if (i->p && *i->p) {
1089 		ch = *i->p++;
1090 	} else {
1091 		/* need to double check i->file because we might be doing something
1092 		 * more complicated by now, like sourcing or substituting. */
1093 #ifndef __U_BOOT__
1094 		if (i->__promptme && interactive && i->file == stdin) {
1095 			while(! i->p || (interactive && strlen(i->p)==0) ) {
1096 #else
1097 			while(! i->p  || strlen(i->p)==0 ) {
1098 #endif
1099 				get_user_input(i);
1100 			}
1101 			i->promptmode=2;
1102 #ifndef __U_BOOT__
1103 			i->__promptme = 0;
1104 #endif
1105 			if (i->p && *i->p) {
1106 				ch = *i->p++;
1107 			}
1108 #ifndef __U_BOOT__
1109 		} else {
1110 			ch = fgetc(i->file);
1111 		}
1112 
1113 #endif
1114 		debug_printf("b_getch: got a %d\n", ch);
1115 	}
1116 #ifndef __U_BOOT__
1117 	if (ch == '\n') i->__promptme=1;
1118 #endif
1119 	return ch;
1120 }
1121 
1122 /* All the callers guarantee this routine will never be
1123  * used right after a newline, so prompting is not needed.
1124  */
1125 static int file_peek(struct in_str *i)
1126 {
1127 #ifndef __U_BOOT__
1128 	if (i->p && *i->p) {
1129 #endif
1130 		return *i->p;
1131 #ifndef __U_BOOT__
1132 	} else {
1133 		i->peek_buf[0] = fgetc(i->file);
1134 		i->peek_buf[1] = '\0';
1135 		i->p = i->peek_buf;
1136 		debug_printf("b_peek: got a %d\n", *i->p);
1137 		return *i->p;
1138 	}
1139 #endif
1140 }
1141 
1142 #ifndef __U_BOOT__
1143 static void setup_file_in_str(struct in_str *i, FILE *f)
1144 #else
1145 static void setup_file_in_str(struct in_str *i)
1146 #endif
1147 {
1148 	i->peek = file_peek;
1149 	i->get = file_get;
1150 	i->__promptme=1;
1151 	i->promptmode=1;
1152 #ifndef __U_BOOT__
1153 	i->file = f;
1154 #endif
1155 	i->p = NULL;
1156 }
1157 
1158 static void setup_string_in_str(struct in_str *i, const char *s)
1159 {
1160 	i->peek = static_peek;
1161 	i->get = static_get;
1162 	i->__promptme=1;
1163 	i->promptmode=1;
1164 	i->p = s;
1165 }
1166 
1167 #ifndef __U_BOOT__
1168 static void mark_open(int fd)
1169 {
1170 	struct close_me *new = xmalloc(sizeof(struct close_me));
1171 	new->fd = fd;
1172 	new->next = close_me_head;
1173 	close_me_head = new;
1174 }
1175 
1176 static void mark_closed(int fd)
1177 {
1178 	struct close_me *tmp;
1179 	if (close_me_head == NULL || close_me_head->fd != fd)
1180 		error_msg_and_die("corrupt close_me");
1181 	tmp = close_me_head;
1182 	close_me_head = close_me_head->next;
1183 	free(tmp);
1184 }
1185 
1186 static void close_all(void)
1187 {
1188 	struct close_me *c;
1189 	for (c=close_me_head; c; c=c->next) {
1190 		close(c->fd);
1191 	}
1192 	close_me_head = NULL;
1193 }
1194 
1195 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1196  * and stderr if they are redirected. */
1197 static int setup_redirects(struct child_prog *prog, int squirrel[])
1198 {
1199 	int openfd, mode;
1200 	struct redir_struct *redir;
1201 
1202 	for (redir=prog->redirects; redir; redir=redir->next) {
1203 		if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1204 			/* something went wrong in the parse.  Pretend it didn't happen */
1205 			continue;
1206 		}
1207 		if (redir->dup == -1) {
1208 			mode=redir_table[redir->type].mode;
1209 			openfd = open(redir->word.gl_pathv[0], mode, 0666);
1210 			if (openfd < 0) {
1211 			/* this could get lost if stderr has been redirected, but
1212 			   bash and ash both lose it as well (though zsh doesn't!) */
1213 				perror_msg("error opening %s", redir->word.gl_pathv[0]);
1214 				return 1;
1215 			}
1216 		} else {
1217 			openfd = redir->dup;
1218 		}
1219 
1220 		if (openfd != redir->fd) {
1221 			if (squirrel && redir->fd < 3) {
1222 				squirrel[redir->fd] = dup(redir->fd);
1223 			}
1224 			if (openfd == -3) {
1225 				close(openfd);
1226 			} else {
1227 				dup2(openfd, redir->fd);
1228 				if (redir->dup == -1)
1229 					close (openfd);
1230 			}
1231 		}
1232 	}
1233 	return 0;
1234 }
1235 
1236 static void restore_redirects(int squirrel[])
1237 {
1238 	int i, fd;
1239 	for (i=0; i<3; i++) {
1240 		fd = squirrel[i];
1241 		if (fd != -1) {
1242 			/* No error checking.  I sure wouldn't know what
1243 			 * to do with an error if I found one! */
1244 			dup2(fd, i);
1245 			close(fd);
1246 		}
1247 	}
1248 }
1249 
1250 /* never returns */
1251 /* XXX no exit() here.  If you don't exec, use _exit instead.
1252  * The at_exit handlers apparently confuse the calling process,
1253  * in particular stdin handling.  Not sure why? */
1254 static void pseudo_exec(struct child_prog *child)
1255 {
1256 	int i, rcode;
1257 	char *p;
1258 	struct built_in_command *x;
1259 	if (child->argv) {
1260 		for (i=0; is_assignment(child->argv[i]); i++) {
1261 			debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
1262 			p = insert_var_value(child->argv[i]);
1263 			putenv(strdup(p));
1264 			if (p != child->argv[i]) free(p);
1265 		}
1266 		child->argv+=i;  /* XXX this hack isn't so horrible, since we are about
1267 					to exit, and therefore don't need to keep data
1268 					structures consistent for free() use. */
1269 		/* If a variable is assigned in a forest, and nobody listens,
1270 		 * was it ever really set?
1271 		 */
1272 		if (child->argv[0] == NULL) {
1273 			_exit(EXIT_SUCCESS);
1274 		}
1275 
1276 		/*
1277 		 * Check if the command matches any of the builtins.
1278 		 * Depending on context, this might be redundant.  But it's
1279 		 * easier to waste a few CPU cycles than it is to figure out
1280 		 * if this is one of those cases.
1281 		 */
1282 		for (x = bltins; x->cmd; x++) {
1283 			if (strcmp(child->argv[0], x->cmd) == 0 ) {
1284 				debug_printf("builtin exec %s\n", child->argv[0]);
1285 				rcode = x->function(child);
1286 				fflush(stdout);
1287 				_exit(rcode);
1288 			}
1289 		}
1290 
1291 		/* Check if the command matches any busybox internal commands
1292 		 * ("applets") here.
1293 		 * FIXME: This feature is not 100% safe, since
1294 		 * BusyBox is not fully reentrant, so we have no guarantee the things
1295 		 * from the .bss are still zeroed, or that things from .data are still
1296 		 * at their defaults.  We could exec ourself from /proc/self/exe, but I
1297 		 * really dislike relying on /proc for things.  We could exec ourself
1298 		 * from global_argv[0], but if we are in a chroot, we may not be able
1299 		 * to find ourself... */
1300 #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1301 		{
1302 			int argc_l;
1303 			char** argv_l=child->argv;
1304 			char *name = child->argv[0];
1305 
1306 #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
1307 			/* Following discussions from November 2000 on the busybox mailing
1308 			 * list, the default configuration, (without
1309 			 * get_last_path_component()) lets the user force use of an
1310 			 * external command by specifying the full (with slashes) filename.
1311 			 * If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN then applets
1312 			 * _aways_ override external commands, so if you want to run
1313 			 * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the
1314 			 * filesystem and is _not_ busybox.  Some systems may want this,
1315 			 * most do not.  */
1316 			name = get_last_path_component(name);
1317 #endif
1318 			/* Count argc for use in a second... */
1319 			for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
1320 			optind = 1;
1321 			debug_printf("running applet %s\n", name);
1322 			run_applet_by_name(name, argc_l, child->argv);
1323 		}
1324 #endif
1325 		debug_printf("exec of %s\n",child->argv[0]);
1326 		execvp(child->argv[0],child->argv);
1327 		perror_msg("couldn't exec: %s",child->argv[0]);
1328 		_exit(1);
1329 	} else if (child->group) {
1330 		debug_printf("runtime nesting to group\n");
1331 		interactive=0;    /* crucial!!!! */
1332 		rcode = run_list_real(child->group);
1333 		/* OK to leak memory by not calling free_pipe_list,
1334 		 * since this process is about to exit */
1335 		_exit(rcode);
1336 	} else {
1337 		/* Can happen.  See what bash does with ">foo" by itself. */
1338 		debug_printf("trying to pseudo_exec null command\n");
1339 		_exit(EXIT_SUCCESS);
1340 	}
1341 }
1342 
1343 static void insert_bg_job(struct pipe *pi)
1344 {
1345 	struct pipe *thejob;
1346 
1347 	/* Linear search for the ID of the job to use */
1348 	pi->jobid = 1;
1349 	for (thejob = job_list; thejob; thejob = thejob->next)
1350 		if (thejob->jobid >= pi->jobid)
1351 			pi->jobid = thejob->jobid + 1;
1352 
1353 	/* add thejob to the list of running jobs */
1354 	if (!job_list) {
1355 		thejob = job_list = xmalloc(sizeof(*thejob));
1356 	} else {
1357 		for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
1358 		thejob->next = xmalloc(sizeof(*thejob));
1359 		thejob = thejob->next;
1360 	}
1361 
1362 	/* physically copy the struct job */
1363 	memcpy(thejob, pi, sizeof(struct pipe));
1364 	thejob->next = NULL;
1365 	thejob->running_progs = thejob->num_progs;
1366 	thejob->stopped_progs = 0;
1367 	thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1368 
1369 	/*if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) */
1370 	{
1371 		char *bar=thejob->text;
1372 		char **foo=pi->progs[0].argv;
1373 		while(foo && *foo) {
1374 			bar += sprintf(bar, "%s ", *foo++);
1375 		}
1376 	}
1377 
1378 	/* we don't wait for background thejobs to return -- append it
1379 	   to the list of backgrounded thejobs and leave it alone */
1380 	printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1381 	last_bg_pid = thejob->progs[0].pid;
1382 	last_jobid = thejob->jobid;
1383 }
1384 
1385 /* remove a backgrounded job */
1386 static void remove_bg_job(struct pipe *pi)
1387 {
1388 	struct pipe *prev_pipe;
1389 
1390 	if (pi == job_list) {
1391 		job_list = pi->next;
1392 	} else {
1393 		prev_pipe = job_list;
1394 		while (prev_pipe->next != pi)
1395 			prev_pipe = prev_pipe->next;
1396 		prev_pipe->next = pi->next;
1397 	}
1398 	if (job_list)
1399 		last_jobid = job_list->jobid;
1400 	else
1401 		last_jobid = 0;
1402 
1403 	pi->stopped_progs = 0;
1404 	free_pipe(pi, 0);
1405 	free(pi);
1406 }
1407 
1408 /* Checks to see if any processes have exited -- if they
1409    have, figure out why and see if a job has completed */
1410 static int checkjobs(struct pipe* fg_pipe)
1411 {
1412 	int attributes;
1413 	int status;
1414 	int prognum = 0;
1415 	struct pipe *pi;
1416 	pid_t childpid;
1417 
1418 	attributes = WUNTRACED;
1419 	if (fg_pipe==NULL) {
1420 		attributes |= WNOHANG;
1421 	}
1422 
1423 	while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1424 		if (fg_pipe) {
1425 			int i, rcode = 0;
1426 			for (i=0; i < fg_pipe->num_progs; i++) {
1427 				if (fg_pipe->progs[i].pid == childpid) {
1428 					if (i==fg_pipe->num_progs-1)
1429 						rcode=WEXITSTATUS(status);
1430 					(fg_pipe->num_progs)--;
1431 					return(rcode);
1432 				}
1433 			}
1434 		}
1435 
1436 		for (pi = job_list; pi; pi = pi->next) {
1437 			prognum = 0;
1438 			while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1439 				prognum++;
1440 			}
1441 			if (prognum < pi->num_progs)
1442 				break;
1443 		}
1444 
1445 		if(pi==NULL) {
1446 			debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
1447 			continue;
1448 		}
1449 
1450 		if (WIFEXITED(status) || WIFSIGNALED(status)) {
1451 			/* child exited */
1452 			pi->running_progs--;
1453 			pi->progs[prognum].pid = 0;
1454 
1455 			if (!pi->running_progs) {
1456 				printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
1457 				remove_bg_job(pi);
1458 			}
1459 		} else {
1460 			/* child stopped */
1461 			pi->stopped_progs++;
1462 			pi->progs[prognum].is_stopped = 1;
1463 
1464 #if 0
1465 			/* Printing this stuff is a pain, since it tends to
1466 			 * overwrite the prompt an inconveinient moments.  So
1467 			 * don't do that.  */
1468 			if (pi->stopped_progs == pi->num_progs) {
1469 				printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
1470 			}
1471 #endif
1472 		}
1473 	}
1474 
1475 	if (childpid == -1 && errno != ECHILD)
1476 		perror_msg("waitpid");
1477 
1478 	/* move the shell to the foreground */
1479 	/*if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) */
1480 	/*	perror_msg("tcsetpgrp-2"); */
1481 	return -1;
1482 }
1483 
1484 /* Figure out our controlling tty, checking in order stderr,
1485  * stdin, and stdout.  If check_pgrp is set, also check that
1486  * we belong to the foreground process group associated with
1487  * that tty.  The value of shell_terminal is needed in order to call
1488  * tcsetpgrp(shell_terminal, ...); */
1489 void controlling_tty(int check_pgrp)
1490 {
1491 	pid_t curpgrp;
1492 
1493 	if ((curpgrp = tcgetpgrp(shell_terminal = 2)) < 0
1494 			&& (curpgrp = tcgetpgrp(shell_terminal = 0)) < 0
1495 			&& (curpgrp = tcgetpgrp(shell_terminal = 1)) < 0)
1496 		goto shell_terminal_error;
1497 
1498 	if (check_pgrp && curpgrp != getpgid(0))
1499 		goto shell_terminal_error;
1500 
1501 	return;
1502 
1503 shell_terminal_error:
1504 		shell_terminal = -1;
1505 		return;
1506 }
1507 #endif
1508 
1509 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1510  * to finish.  See checkjobs().
1511  *
1512  * return code is normally -1, when the caller has to wait for children
1513  * to finish to determine the exit status of the pipe.  If the pipe
1514  * is a simple builtin command, however, the action is done by the
1515  * time run_pipe_real returns, and the exit code is provided as the
1516  * return value.
1517  *
1518  * The input of the pipe is always stdin, the output is always
1519  * stdout.  The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1520  * because it tries to avoid running the command substitution in
1521  * subshell, when that is in fact necessary.  The subshell process
1522  * now has its stdout directed to the input of the appropriate pipe,
1523  * so this routine is noticeably simpler.
1524  */
1525 static int run_pipe_real(struct pipe *pi)
1526 {
1527 	int i;
1528 #ifndef __U_BOOT__
1529 	int nextin, nextout;
1530 	int pipefds[2];				/* pipefds[0] is for reading */
1531 	struct child_prog *child;
1532 	struct built_in_command *x;
1533 	char *p;
1534 # if __GNUC__
1535 	/* Avoid longjmp clobbering */
1536 	(void) &i;
1537 	(void) &nextin;
1538 	(void) &nextout;
1539 	(void) &child;
1540 # endif
1541 #else
1542 	int nextin;
1543 	int flag = do_repeat ? CMD_FLAG_REPEAT : 0;
1544 	struct child_prog *child;
1545 	char *p;
1546 # if __GNUC__
1547 	/* Avoid longjmp clobbering */
1548 	(void) &i;
1549 	(void) &nextin;
1550 	(void) &child;
1551 # endif
1552 #endif	/* __U_BOOT__ */
1553 
1554 	nextin = 0;
1555 #ifndef __U_BOOT__
1556 	pi->pgrp = -1;
1557 #endif
1558 
1559 	/* Check if this is a simple builtin (not part of a pipe).
1560 	 * Builtins within pipes have to fork anyway, and are handled in
1561 	 * pseudo_exec.  "echo foo | read bar" doesn't work on bash, either.
1562 	 */
1563 	if (pi->num_progs == 1) child = & (pi->progs[0]);
1564 #ifndef __U_BOOT__
1565 	if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1566 		int squirrel[] = {-1, -1, -1};
1567 		int rcode;
1568 		debug_printf("non-subshell grouping\n");
1569 		setup_redirects(child, squirrel);
1570 		/* XXX could we merge code with following builtin case,
1571 		 * by creating a pseudo builtin that calls run_list_real? */
1572 		rcode = run_list_real(child->group);
1573 		restore_redirects(squirrel);
1574 #else
1575 		if (pi->num_progs == 1 && child->group) {
1576 		int rcode;
1577 		debug_printf("non-subshell grouping\n");
1578 		rcode = run_list_real(child->group);
1579 #endif
1580 		return rcode;
1581 	} else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1582 		for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
1583 		if (i!=0 && child->argv[i]==NULL) {
1584 			/* assignments, but no command: set the local environment */
1585 			for (i=0; child->argv[i]!=NULL; i++) {
1586 
1587 				/* Ok, this case is tricky.  We have to decide if this is a
1588 				 * local variable, or an already exported variable.  If it is
1589 				 * already exported, we have to export the new value.  If it is
1590 				 * not exported, we need only set this as a local variable.
1591 				 * This junk is all to decide whether or not to export this
1592 				 * variable. */
1593 				int export_me=0;
1594 				char *name, *value;
1595 				name = xstrdup(child->argv[i]);
1596 				debug_printf("Local environment set: %s\n", name);
1597 				value = strchr(name, '=');
1598 				if (value)
1599 					*value=0;
1600 #ifndef __U_BOOT__
1601 				if ( get_local_var(name)) {
1602 					export_me=1;
1603 				}
1604 #endif
1605 				free(name);
1606 				p = insert_var_value(child->argv[i]);
1607 				set_local_var(p, export_me);
1608 				if (p != child->argv[i]) free(p);
1609 			}
1610 			return EXIT_SUCCESS;   /* don't worry about errors in set_local_var() yet */
1611 		}
1612 		for (i = 0; is_assignment(child->argv[i]); i++) {
1613 			p = insert_var_value(child->argv[i]);
1614 #ifndef __U_BOOT__
1615 			putenv(strdup(p));
1616 #else
1617 			set_local_var(p, 0);
1618 #endif
1619 			if (p != child->argv[i]) {
1620 				child->sp--;
1621 				free(p);
1622 			}
1623 		}
1624 		if (child->sp) {
1625 			char * str = NULL;
1626 
1627 			str = make_string(child->argv + i,
1628 					  child->argv_nonnull + i);
1629 			parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1630 			free(str);
1631 			return last_return_code;
1632 		}
1633 #ifndef __U_BOOT__
1634 		for (x = bltins; x->cmd; x++) {
1635 			if (strcmp(child->argv[i], x->cmd) == 0 ) {
1636 				int squirrel[] = {-1, -1, -1};
1637 				int rcode;
1638 				if (x->function == builtin_exec && child->argv[i+1]==NULL) {
1639 					debug_printf("magic exec\n");
1640 					setup_redirects(child,NULL);
1641 					return EXIT_SUCCESS;
1642 				}
1643 				debug_printf("builtin inline %s\n", child->argv[0]);
1644 				/* XXX setup_redirects acts on file descriptors, not FILEs.
1645 				 * This is perfect for work that comes after exec().
1646 				 * Is it really safe for inline use?  Experimentally,
1647 				 * things seem to work with glibc. */
1648 				setup_redirects(child, squirrel);
1649 
1650 				child->argv += i;  /* XXX horrible hack */
1651 				rcode = x->function(child);
1652 				/* XXX restore hack so free() can work right */
1653 				child->argv -= i;
1654 				restore_redirects(squirrel);
1655 			}
1656 			return rcode;
1657 		}
1658 #else
1659 		/* check ";", because ,example , argv consist from
1660 		 * "help;flinfo" must not execute
1661 		 */
1662 		if (strchr(child->argv[i], ';')) {
1663 			printf("Unknown command '%s' - try 'help' or use "
1664 					"'run' command\n", child->argv[i]);
1665 			return -1;
1666 		}
1667 		/* Process the command */
1668 		return cmd_process(flag, child->argc, child->argv,
1669 				   &flag_repeat, NULL);
1670 #endif
1671 	}
1672 #ifndef __U_BOOT__
1673 
1674 	for (i = 0; i < pi->num_progs; i++) {
1675 		child = & (pi->progs[i]);
1676 
1677 		/* pipes are inserted between pairs of commands */
1678 		if ((i + 1) < pi->num_progs) {
1679 			if (pipe(pipefds)<0) perror_msg_and_die("pipe");
1680 			nextout = pipefds[1];
1681 		} else {
1682 			nextout=1;
1683 			pipefds[0] = -1;
1684 		}
1685 
1686 		/* XXX test for failed fork()? */
1687 		if (!(child->pid = fork())) {
1688 			/* Set the handling for job control signals back to the default.  */
1689 			signal(SIGINT, SIG_DFL);
1690 			signal(SIGQUIT, SIG_DFL);
1691 			signal(SIGTERM, SIG_DFL);
1692 			signal(SIGTSTP, SIG_DFL);
1693 			signal(SIGTTIN, SIG_DFL);
1694 			signal(SIGTTOU, SIG_DFL);
1695 			signal(SIGCHLD, SIG_DFL);
1696 
1697 			close_all();
1698 
1699 			if (nextin != 0) {
1700 				dup2(nextin, 0);
1701 				close(nextin);
1702 			}
1703 			if (nextout != 1) {
1704 				dup2(nextout, 1);
1705 				close(nextout);
1706 			}
1707 			if (pipefds[0]!=-1) {
1708 				close(pipefds[0]);  /* opposite end of our output pipe */
1709 			}
1710 
1711 			/* Like bash, explicit redirects override pipes,
1712 			 * and the pipe fd is available for dup'ing. */
1713 			setup_redirects(child,NULL);
1714 
1715 			if (interactive && pi->followup!=PIPE_BG) {
1716 				/* If we (the child) win the race, put ourselves in the process
1717 				 * group whose leader is the first process in this pipe. */
1718 				if (pi->pgrp < 0) {
1719 					pi->pgrp = getpid();
1720 				}
1721 				if (setpgid(0, pi->pgrp) == 0) {
1722 					tcsetpgrp(2, pi->pgrp);
1723 				}
1724 			}
1725 
1726 			pseudo_exec(child);
1727 		}
1728 
1729 
1730 		/* put our child in the process group whose leader is the
1731 		   first process in this pipe */
1732 		if (pi->pgrp < 0) {
1733 			pi->pgrp = child->pid;
1734 		}
1735 		/* Don't check for errors.  The child may be dead already,
1736 		 * in which case setpgid returns error code EACCES. */
1737 		setpgid(child->pid, pi->pgrp);
1738 
1739 		if (nextin != 0)
1740 			close(nextin);
1741 		if (nextout != 1)
1742 			close(nextout);
1743 
1744 		/* If there isn't another process, nextin is garbage
1745 		   but it doesn't matter */
1746 		nextin = pipefds[0];
1747 	}
1748 #endif
1749 	return -1;
1750 }
1751 
1752 static int run_list_real(struct pipe *pi)
1753 {
1754 	char *save_name = NULL;
1755 	char **list = NULL;
1756 	char **save_list = NULL;
1757 	struct pipe *rpipe;
1758 	int flag_rep = 0;
1759 #ifndef __U_BOOT__
1760 	int save_num_progs;
1761 #endif
1762 	int rcode=0, flag_skip=1;
1763 	int flag_restore = 0;
1764 	int if_code=0, next_if_code=0;  /* need double-buffer to handle elif */
1765 	reserved_style rmode, skip_more_in_this_rmode=RES_XXXX;
1766 	/* check syntax for "for" */
1767 	for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1768 		if ((rpipe->r_mode == RES_IN ||
1769 		    rpipe->r_mode == RES_FOR) &&
1770 		    (rpipe->next == NULL)) {
1771 				syntax();
1772 #ifdef __U_BOOT__
1773 				flag_repeat = 0;
1774 #endif
1775 				return 1;
1776 		}
1777 		if ((rpipe->r_mode == RES_IN &&
1778 			(rpipe->next->r_mode == RES_IN &&
1779 			rpipe->next->progs->argv != NULL))||
1780 			(rpipe->r_mode == RES_FOR &&
1781 			rpipe->next->r_mode != RES_IN)) {
1782 				syntax();
1783 #ifdef __U_BOOT__
1784 				flag_repeat = 0;
1785 #endif
1786 				return 1;
1787 		}
1788 	}
1789 	for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1790 		if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
1791 			pi->r_mode == RES_FOR) {
1792 #ifdef __U_BOOT__
1793 				/* check Ctrl-C */
1794 				ctrlc();
1795 				if ((had_ctrlc())) {
1796 					return 1;
1797 				}
1798 #endif
1799 				flag_restore = 0;
1800 				if (!rpipe) {
1801 					flag_rep = 0;
1802 					rpipe = pi;
1803 				}
1804 		}
1805 		rmode = pi->r_mode;
1806 		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);
1807 		if (rmode == skip_more_in_this_rmode && flag_skip) {
1808 			if (pi->followup == PIPE_SEQ) flag_skip=0;
1809 			continue;
1810 		}
1811 		flag_skip = 1;
1812 		skip_more_in_this_rmode = RES_XXXX;
1813 		if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
1814 		if (rmode == RES_THEN &&  if_code) continue;
1815 		if (rmode == RES_ELSE && !if_code) continue;
1816 		if (rmode == RES_ELIF && !if_code) break;
1817 		if (rmode == RES_FOR && pi->num_progs) {
1818 			if (!list) {
1819 				/* if no variable values after "in" we skip "for" */
1820 				if (!pi->next->progs->argv) continue;
1821 				/* create list of variable values */
1822 				list = make_list_in(pi->next->progs->argv,
1823 					pi->progs->argv[0]);
1824 				save_list = list;
1825 				save_name = pi->progs->argv[0];
1826 				pi->progs->argv[0] = NULL;
1827 				flag_rep = 1;
1828 			}
1829 			if (!(*list)) {
1830 				free(pi->progs->argv[0]);
1831 				free(save_list);
1832 				list = NULL;
1833 				flag_rep = 0;
1834 				pi->progs->argv[0] = save_name;
1835 #ifndef __U_BOOT__
1836 				pi->progs->glob_result.gl_pathv[0] =
1837 					pi->progs->argv[0];
1838 #endif
1839 				continue;
1840 			} else {
1841 				/* insert new value from list for variable */
1842 				if (pi->progs->argv[0])
1843 					free(pi->progs->argv[0]);
1844 				pi->progs->argv[0] = *list++;
1845 #ifndef __U_BOOT__
1846 				pi->progs->glob_result.gl_pathv[0] =
1847 					pi->progs->argv[0];
1848 #endif
1849 			}
1850 		}
1851 		if (rmode == RES_IN) continue;
1852 		if (rmode == RES_DO) {
1853 			if (!flag_rep) continue;
1854 		}
1855 		if (rmode == RES_DONE) {
1856 			if (flag_rep) {
1857 				flag_restore = 1;
1858 			} else {
1859 				rpipe = NULL;
1860 			}
1861 		}
1862 		if (pi->num_progs == 0) continue;
1863 #ifndef __U_BOOT__
1864 		save_num_progs = pi->num_progs; /* save number of programs */
1865 #endif
1866 		rcode = run_pipe_real(pi);
1867 		debug_printf("run_pipe_real returned %d\n",rcode);
1868 #ifndef __U_BOOT__
1869 		if (rcode!=-1) {
1870 			/* We only ran a builtin: rcode was set by the return value
1871 			 * of run_pipe_real(), and we don't need to wait for anything. */
1872 		} else if (pi->followup==PIPE_BG) {
1873 			/* XXX check bash's behavior with nontrivial pipes */
1874 			/* XXX compute jobid */
1875 			/* XXX what does bash do with attempts to background builtins? */
1876 			insert_bg_job(pi);
1877 			rcode = EXIT_SUCCESS;
1878 		} else {
1879 			if (interactive) {
1880 				/* move the new process group into the foreground */
1881 				if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1882 					perror_msg("tcsetpgrp-3");
1883 				rcode = checkjobs(pi);
1884 				/* move the shell to the foreground */
1885 				if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1886 					perror_msg("tcsetpgrp-4");
1887 			} else {
1888 				rcode = checkjobs(pi);
1889 			}
1890 			debug_printf("checkjobs returned %d\n",rcode);
1891 		}
1892 		last_return_code=rcode;
1893 #else
1894 		if (rcode < -1) {
1895 			last_return_code = -rcode - 2;
1896 			return -2;	/* exit */
1897 		}
1898 		last_return_code=(rcode == 0) ? 0 : 1;
1899 #endif
1900 #ifndef __U_BOOT__
1901 		pi->num_progs = save_num_progs; /* restore number of programs */
1902 #endif
1903 		if ( rmode == RES_IF || rmode == RES_ELIF )
1904 			next_if_code=rcode;  /* can be overwritten a number of times */
1905 		if (rmode == RES_WHILE)
1906 			flag_rep = !last_return_code;
1907 		if (rmode == RES_UNTIL)
1908 			flag_rep = last_return_code;
1909 		if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
1910 		     (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
1911 			skip_more_in_this_rmode=rmode;
1912 #ifndef __U_BOOT__
1913 		checkjobs(NULL);
1914 #endif
1915 	}
1916 	return rcode;
1917 }
1918 
1919 /* broken, of course, but OK for testing */
1920 static char *indenter(int i)
1921 {
1922 	static char blanks[]="                                    ";
1923 	return &blanks[sizeof(blanks)-i-1];
1924 }
1925 
1926 /* return code is the exit status of the pipe */
1927 static int free_pipe(struct pipe *pi, int indent)
1928 {
1929 	char **p;
1930 	struct child_prog *child;
1931 #ifndef __U_BOOT__
1932 	struct redir_struct *r, *rnext;
1933 #endif
1934 	int a, i, ret_code=0;
1935 	char *ind = indenter(indent);
1936 
1937 #ifndef __U_BOOT__
1938 	if (pi->stopped_progs > 0)
1939 		return ret_code;
1940 	final_printf("%s run pipe: (pid %d)\n",ind,getpid());
1941 #endif
1942 	for (i=0; i<pi->num_progs; i++) {
1943 		child = &pi->progs[i];
1944 		final_printf("%s  command %d:\n",ind,i);
1945 		if (child->argv) {
1946 			for (a=0,p=child->argv; *p; a++,p++) {
1947 				final_printf("%s   argv[%d] = %s\n",ind,a,*p);
1948 			}
1949 #ifndef __U_BOOT__
1950 			globfree(&child->glob_result);
1951 #else
1952 			for (a = 0; a < child->argc; a++) {
1953 				free(child->argv[a]);
1954 			}
1955 			free(child->argv);
1956 			free(child->argv_nonnull);
1957 			child->argc = 0;
1958 #endif
1959 			child->argv=NULL;
1960 		} else if (child->group) {
1961 #ifndef __U_BOOT__
1962 			final_printf("%s   begin group (subshell:%d)\n",ind, child->subshell);
1963 #endif
1964 			ret_code = free_pipe_list(child->group,indent+3);
1965 			final_printf("%s   end group\n",ind);
1966 		} else {
1967 			final_printf("%s   (nil)\n",ind);
1968 		}
1969 #ifndef __U_BOOT__
1970 		for (r=child->redirects; r; r=rnext) {
1971 			final_printf("%s   redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
1972 			if (r->dup == -1) {
1973 				/* guard against the case >$FOO, where foo is unset or blank */
1974 				if (r->word.gl_pathv) {
1975 					final_printf(" %s\n", *r->word.gl_pathv);
1976 					globfree(&r->word);
1977 				}
1978 			} else {
1979 				final_printf("&%d\n", r->dup);
1980 			}
1981 			rnext=r->next;
1982 			free(r);
1983 		}
1984 		child->redirects=NULL;
1985 #endif
1986 	}
1987 	free(pi->progs);   /* children are an array, they get freed all at once */
1988 	pi->progs=NULL;
1989 	return ret_code;
1990 }
1991 
1992 static int free_pipe_list(struct pipe *head, int indent)
1993 {
1994 	int rcode=0;   /* if list has no members */
1995 	struct pipe *pi, *next;
1996 	char *ind = indenter(indent);
1997 	for (pi=head; pi; pi=next) {
1998 		final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
1999 		rcode = free_pipe(pi, indent);
2000 		final_printf("%s pipe followup code %d\n", ind, pi->followup);
2001 		next=pi->next;
2002 		pi->next=NULL;
2003 		free(pi);
2004 	}
2005 	return rcode;
2006 }
2007 
2008 /* Select which version we will use */
2009 static int run_list(struct pipe *pi)
2010 {
2011 	int rcode=0;
2012 #ifndef __U_BOOT__
2013 	if (fake_mode==0) {
2014 #endif
2015 		rcode = run_list_real(pi);
2016 #ifndef __U_BOOT__
2017 	}
2018 #endif
2019 	/* free_pipe_list has the side effect of clearing memory
2020 	 * In the long run that function can be merged with run_list_real,
2021 	 * but doing that now would hobble the debugging effort. */
2022 	free_pipe_list(pi,0);
2023 	return rcode;
2024 }
2025 
2026 /* The API for glob is arguably broken.  This routine pushes a non-matching
2027  * string into the output structure, removing non-backslashed backslashes.
2028  * If someone can prove me wrong, by performing this function within the
2029  * original glob(3) api, feel free to rewrite this routine into oblivion.
2030  * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
2031  * XXX broken if the last character is '\\', check that before calling.
2032  */
2033 #ifndef __U_BOOT__
2034 static int globhack(const char *src, int flags, glob_t *pglob)
2035 {
2036 	int cnt=0, pathc;
2037 	const char *s;
2038 	char *dest;
2039 	for (cnt=1, s=src; s && *s; s++) {
2040 		if (*s == '\\') s++;
2041 		cnt++;
2042 	}
2043 	dest = malloc(cnt);
2044 	if (!dest) return GLOB_NOSPACE;
2045 	if (!(flags & GLOB_APPEND)) {
2046 		pglob->gl_pathv=NULL;
2047 		pglob->gl_pathc=0;
2048 		pglob->gl_offs=0;
2049 		pglob->gl_offs=0;
2050 	}
2051 	pathc = ++pglob->gl_pathc;
2052 	pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
2053 	if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
2054 	pglob->gl_pathv[pathc-1]=dest;
2055 	pglob->gl_pathv[pathc]=NULL;
2056 	for (s=src; s && *s; s++, dest++) {
2057 		if (*s == '\\') s++;
2058 		*dest = *s;
2059 	}
2060 	*dest='\0';
2061 	return 0;
2062 }
2063 
2064 /* XXX broken if the last character is '\\', check that before calling */
2065 static int glob_needed(const char *s)
2066 {
2067 	for (; *s; s++) {
2068 		if (*s == '\\') s++;
2069 		if (strchr("*[?",*s)) return 1;
2070 	}
2071 	return 0;
2072 }
2073 
2074 #if 0
2075 static void globprint(glob_t *pglob)
2076 {
2077 	int i;
2078 	debug_printf("glob_t at %p:\n", pglob);
2079 	debug_printf("  gl_pathc=%d  gl_pathv=%p  gl_offs=%d  gl_flags=%d\n",
2080 		pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
2081 	for (i=0; i<pglob->gl_pathc; i++)
2082 		debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
2083 			pglob->gl_pathv[i], pglob->gl_pathv[i]);
2084 }
2085 #endif
2086 
2087 static int xglob(o_string *dest, int flags, glob_t *pglob)
2088 {
2089 	int gr;
2090 
2091 	/* short-circuit for null word */
2092 	/* we can code this better when the debug_printf's are gone */
2093 	if (dest->length == 0) {
2094 		if (dest->nonnull) {
2095 			/* bash man page calls this an "explicit" null */
2096 			gr = globhack(dest->data, flags, pglob);
2097 			debug_printf("globhack returned %d\n",gr);
2098 		} else {
2099 			return 0;
2100 		}
2101 	} else if (glob_needed(dest->data)) {
2102 		gr = glob(dest->data, flags, NULL, pglob);
2103 		debug_printf("glob returned %d\n",gr);
2104 		if (gr == GLOB_NOMATCH) {
2105 			/* quote removal, or more accurately, backslash removal */
2106 			gr = globhack(dest->data, flags, pglob);
2107 			debug_printf("globhack returned %d\n",gr);
2108 		}
2109 	} else {
2110 		gr = globhack(dest->data, flags, pglob);
2111 		debug_printf("globhack returned %d\n",gr);
2112 	}
2113 	if (gr == GLOB_NOSPACE)
2114 		error_msg_and_die("out of memory during glob");
2115 	if (gr != 0) { /* GLOB_ABORTED ? */
2116 		error_msg("glob(3) error %d",gr);
2117 	}
2118 	/* globprint(glob_target); */
2119 	return gr;
2120 }
2121 #endif
2122 
2123 #ifdef __U_BOOT__
2124 static char *get_dollar_var(char ch);
2125 #endif
2126 
2127 /* This is used to get/check local shell variables */
2128 char *get_local_var(const char *s)
2129 {
2130 	struct variables *cur;
2131 
2132 	if (!s)
2133 		return NULL;
2134 
2135 #ifdef __U_BOOT__
2136 	if (*s == '$')
2137 		return get_dollar_var(s[1]);
2138 #endif
2139 
2140 	for (cur = top_vars; cur; cur=cur->next)
2141 		if(strcmp(cur->name, s)==0)
2142 			return cur->value;
2143 	return NULL;
2144 }
2145 
2146 /* This is used to set local shell variables
2147    flg_export==0 if only local (not exporting) variable
2148    flg_export==1 if "new" exporting environ
2149    flg_export>1  if current startup environ (not call putenv()) */
2150 int set_local_var(const char *s, int flg_export)
2151 {
2152 	char *name, *value;
2153 	int result=0;
2154 	struct variables *cur;
2155 
2156 #ifdef __U_BOOT__
2157 	/* might be possible! */
2158 	if (!isalpha(*s))
2159 		return -1;
2160 #endif
2161 
2162 	name=strdup(s);
2163 
2164 #ifdef __U_BOOT__
2165 	if (getenv(name) != NULL) {
2166 		printf ("ERROR: "
2167 				"There is a global environment variable with the same name.\n");
2168 		free(name);
2169 		return -1;
2170 	}
2171 #endif
2172 	/* Assume when we enter this function that we are already in
2173 	 * NAME=VALUE format.  So the first order of business is to
2174 	 * split 's' on the '=' into 'name' and 'value' */
2175 	value = strchr(name, '=');
2176 	if (value == NULL || *(value + 1) == 0) {
2177 		free(name);
2178 		return -1;
2179 	}
2180 	*value++ = 0;
2181 
2182 	for(cur = top_vars; cur; cur = cur->next) {
2183 		if(strcmp(cur->name, name)==0)
2184 			break;
2185 	}
2186 
2187 	if(cur) {
2188 		if(strcmp(cur->value, value)==0) {
2189 			if(flg_export>0 && cur->flg_export==0)
2190 				cur->flg_export=flg_export;
2191 			else
2192 				result++;
2193 		} else {
2194 			if(cur->flg_read_only) {
2195 				error_msg("%s: readonly variable", name);
2196 				result = -1;
2197 			} else {
2198 				if(flg_export>0 || cur->flg_export>1)
2199 					cur->flg_export=1;
2200 				free(cur->value);
2201 
2202 				cur->value = strdup(value);
2203 			}
2204 		}
2205 	} else {
2206 		cur = malloc(sizeof(struct variables));
2207 		if(!cur) {
2208 			result = -1;
2209 		} else {
2210 			cur->name = strdup(name);
2211 			if (cur->name == NULL) {
2212 				free(cur);
2213 				result = -1;
2214 			} else {
2215 				struct variables *bottom = top_vars;
2216 				cur->value = strdup(value);
2217 				cur->next = NULL;
2218 				cur->flg_export = flg_export;
2219 				cur->flg_read_only = 0;
2220 				while(bottom->next) bottom=bottom->next;
2221 				bottom->next = cur;
2222 			}
2223 		}
2224 	}
2225 
2226 #ifndef __U_BOOT__
2227 	if(result==0 && cur->flg_export==1) {
2228 		*(value-1) = '=';
2229 		result = putenv(name);
2230 	} else {
2231 #endif
2232 		free(name);
2233 #ifndef __U_BOOT__
2234 		if(result>0)            /* equivalent to previous set */
2235 			result = 0;
2236 	}
2237 #endif
2238 	return result;
2239 }
2240 
2241 void unset_local_var(const char *name)
2242 {
2243 	struct variables *cur;
2244 
2245 	if (name) {
2246 		for (cur = top_vars; cur; cur=cur->next) {
2247 			if(strcmp(cur->name, name)==0)
2248 				break;
2249 		}
2250 		if (cur != NULL) {
2251 			struct variables *next = top_vars;
2252 			if(cur->flg_read_only) {
2253 				error_msg("%s: readonly variable", name);
2254 				return;
2255 			} else {
2256 #ifndef __U_BOOT__
2257 				if(cur->flg_export)
2258 					unsetenv(cur->name);
2259 #endif
2260 				free(cur->name);
2261 				free(cur->value);
2262 				while (next->next != cur)
2263 					next = next->next;
2264 				next->next = cur->next;
2265 			}
2266 			free(cur);
2267 		}
2268 	}
2269 }
2270 
2271 static int is_assignment(const char *s)
2272 {
2273 	if (s == NULL)
2274 		return 0;
2275 
2276 	if (!isalpha(*s)) return 0;
2277 	++s;
2278 	while(isalnum(*s) || *s=='_') ++s;
2279 	return *s=='=';
2280 }
2281 
2282 #ifndef __U_BOOT__
2283 /* the src parameter allows us to peek forward to a possible &n syntax
2284  * for file descriptor duplication, e.g., "2>&1".
2285  * Return code is 0 normally, 1 if a syntax error is detected in src.
2286  * Resource errors (in xmalloc) cause the process to exit */
2287 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
2288 	struct in_str *input)
2289 {
2290 	struct child_prog *child=ctx->child;
2291 	struct redir_struct *redir = child->redirects;
2292 	struct redir_struct *last_redir=NULL;
2293 
2294 	/* Create a new redir_struct and drop it onto the end of the linked list */
2295 	while(redir) {
2296 		last_redir=redir;
2297 		redir=redir->next;
2298 	}
2299 	redir = xmalloc(sizeof(struct redir_struct));
2300 	redir->next=NULL;
2301 	redir->word.gl_pathv=NULL;
2302 	if (last_redir) {
2303 		last_redir->next=redir;
2304 	} else {
2305 		child->redirects=redir;
2306 	}
2307 
2308 	redir->type=style;
2309 	redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
2310 
2311 	debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
2312 
2313 	/* Check for a '2>&1' type redirect */
2314 	redir->dup = redirect_dup_num(input);
2315 	if (redir->dup == -2) return 1;  /* syntax error */
2316 	if (redir->dup != -1) {
2317 		/* Erik had a check here that the file descriptor in question
2318 		 * is legit; I postpone that to "run time"
2319 		 * A "-" representation of "close me" shows up as a -3 here */
2320 		debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
2321 	} else {
2322 		/* We do _not_ try to open the file that src points to,
2323 		 * since we need to return and let src be expanded first.
2324 		 * Set ctx->pending_redirect, so we know what to do at the
2325 		 * end of the next parsed word.
2326 		 */
2327 		ctx->pending_redirect = redir;
2328 	}
2329 	return 0;
2330 }
2331 #endif
2332 
2333 static struct pipe *new_pipe(void)
2334 {
2335 	struct pipe *pi;
2336 	pi = xmalloc(sizeof(struct pipe));
2337 	pi->num_progs = 0;
2338 	pi->progs = NULL;
2339 	pi->next = NULL;
2340 	pi->followup = 0;  /* invalid */
2341 	pi->r_mode = RES_NONE;
2342 	return pi;
2343 }
2344 
2345 static void initialize_context(struct p_context *ctx)
2346 {
2347 	ctx->pipe=NULL;
2348 #ifndef __U_BOOT__
2349 	ctx->pending_redirect=NULL;
2350 #endif
2351 	ctx->child=NULL;
2352 	ctx->list_head=new_pipe();
2353 	ctx->pipe=ctx->list_head;
2354 	ctx->w=RES_NONE;
2355 	ctx->stack=NULL;
2356 #ifdef __U_BOOT__
2357 	ctx->old_flag=0;
2358 #endif
2359 	done_command(ctx);   /* creates the memory for working child */
2360 }
2361 
2362 /* normal return is 0
2363  * if a reserved word is found, and processed, return 1
2364  * should handle if, then, elif, else, fi, for, while, until, do, done.
2365  * case, function, and select are obnoxious, save those for later.
2366  */
2367 struct reserved_combo {
2368 	char *literal;
2369 	int code;
2370 	long flag;
2371 };
2372 /* Mostly a list of accepted follow-up reserved words.
2373  * FLAG_END means we are done with the sequence, and are ready
2374  * to turn the compound list into a command.
2375  * FLAG_START means the word must start a new compound list.
2376  */
2377 static struct reserved_combo reserved_list[] = {
2378 	{ "if",    RES_IF,    FLAG_THEN | FLAG_START },
2379 	{ "then",  RES_THEN,  FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2380 	{ "elif",  RES_ELIF,  FLAG_THEN },
2381 	{ "else",  RES_ELSE,  FLAG_FI   },
2382 	{ "fi",    RES_FI,    FLAG_END  },
2383 	{ "for",   RES_FOR,   FLAG_IN   | FLAG_START },
2384 	{ "while", RES_WHILE, FLAG_DO   | FLAG_START },
2385 	{ "until", RES_UNTIL, FLAG_DO   | FLAG_START },
2386 	{ "in",    RES_IN,    FLAG_DO   },
2387 	{ "do",    RES_DO,    FLAG_DONE },
2388 	{ "done",  RES_DONE,  FLAG_END  }
2389 };
2390 #define NRES (sizeof(reserved_list)/sizeof(struct reserved_combo))
2391 
2392 static int reserved_word(o_string *dest, struct p_context *ctx)
2393 {
2394 	struct reserved_combo *r;
2395 	for (r=reserved_list;
2396 		r<reserved_list+NRES; r++) {
2397 		if (strcmp(dest->data, r->literal) == 0) {
2398 			debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2399 			if (r->flag & FLAG_START) {
2400 				struct p_context *new = xmalloc(sizeof(struct p_context));
2401 				debug_printf("push stack\n");
2402 				if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2403 					syntax();
2404 					free(new);
2405 					ctx->w = RES_SNTX;
2406 					b_reset(dest);
2407 					return 1;
2408 				}
2409 				*new = *ctx;   /* physical copy */
2410 				initialize_context(ctx);
2411 				ctx->stack=new;
2412 			} else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2413 				syntax();
2414 				ctx->w = RES_SNTX;
2415 				b_reset(dest);
2416 				return 1;
2417 			}
2418 			ctx->w=r->code;
2419 			ctx->old_flag = r->flag;
2420 			if (ctx->old_flag & FLAG_END) {
2421 				struct p_context *old;
2422 				debug_printf("pop stack\n");
2423 				done_pipe(ctx,PIPE_SEQ);
2424 				old = ctx->stack;
2425 				old->child->group = ctx->list_head;
2426 #ifndef __U_BOOT__
2427 				old->child->subshell = 0;
2428 #endif
2429 				*ctx = *old;   /* physical copy */
2430 				free(old);
2431 			}
2432 			b_reset (dest);
2433 			return 1;
2434 		}
2435 	}
2436 	return 0;
2437 }
2438 
2439 /* normal return is 0.
2440  * Syntax or xglob errors return 1. */
2441 static int done_word(o_string *dest, struct p_context *ctx)
2442 {
2443 	struct child_prog *child=ctx->child;
2444 #ifndef __U_BOOT__
2445 	glob_t *glob_target;
2446 	int gr, flags = 0;
2447 #else
2448 	char *str, *s;
2449 	int argc, cnt;
2450 #endif
2451 
2452 	debug_printf("done_word: %s %p\n", dest->data, child);
2453 	if (dest->length == 0 && !dest->nonnull) {
2454 		debug_printf("  true null, ignored\n");
2455 		return 0;
2456 	}
2457 #ifndef __U_BOOT__
2458 	if (ctx->pending_redirect) {
2459 		glob_target = &ctx->pending_redirect->word;
2460 	} else {
2461 #endif
2462 		if (child->group) {
2463 			syntax();
2464 			return 1;  /* syntax error, groups and arglists don't mix */
2465 		}
2466 		if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2467 			debug_printf("checking %s for reserved-ness\n",dest->data);
2468 			if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2469 		}
2470 #ifndef __U_BOOT__
2471 		glob_target = &child->glob_result;
2472 		if (child->argv) flags |= GLOB_APPEND;
2473 #else
2474 		for (cnt = 1, s = dest->data; s && *s; s++) {
2475 			if (*s == '\\') s++;
2476 			cnt++;
2477 		}
2478 		str = malloc(cnt);
2479 		if (!str) return 1;
2480 		if ( child->argv == NULL) {
2481 			child->argc=0;
2482 		}
2483 		argc = ++child->argc;
2484 		child->argv = realloc(child->argv, (argc+1)*sizeof(*child->argv));
2485 		if (child->argv == NULL) {
2486 			free(str);
2487 			return 1;
2488 		}
2489 		child->argv_nonnull = realloc(child->argv_nonnull,
2490 					(argc+1)*sizeof(*child->argv_nonnull));
2491 		if (child->argv_nonnull == NULL) {
2492 			free(str);
2493 			return 1;
2494 		}
2495 		child->argv[argc-1]=str;
2496 		child->argv_nonnull[argc-1] = dest->nonnull;
2497 		child->argv[argc]=NULL;
2498 		child->argv_nonnull[argc] = 0;
2499 		for (s = dest->data; s && *s; s++,str++) {
2500 			if (*s == '\\') s++;
2501 			*str = *s;
2502 		}
2503 		*str = '\0';
2504 #endif
2505 #ifndef __U_BOOT__
2506 	}
2507 	gr = xglob(dest, flags, glob_target);
2508 	if (gr != 0) return 1;
2509 #endif
2510 
2511 	b_reset(dest);
2512 #ifndef __U_BOOT__
2513 	if (ctx->pending_redirect) {
2514 		ctx->pending_redirect=NULL;
2515 		if (glob_target->gl_pathc != 1) {
2516 			error_msg("ambiguous redirect");
2517 			return 1;
2518 		}
2519 	} else {
2520 		child->argv = glob_target->gl_pathv;
2521 	}
2522 #endif
2523 	if (ctx->w == RES_FOR) {
2524 		done_word(dest,ctx);
2525 		done_pipe(ctx,PIPE_SEQ);
2526 	}
2527 	return 0;
2528 }
2529 
2530 /* The only possible error here is out of memory, in which case
2531  * xmalloc exits. */
2532 static int done_command(struct p_context *ctx)
2533 {
2534 	/* The child is really already in the pipe structure, so
2535 	 * advance the pipe counter and make a new, null child.
2536 	 * Only real trickiness here is that the uncommitted
2537 	 * child structure, to which ctx->child points, is not
2538 	 * counted in pi->num_progs. */
2539 	struct pipe *pi=ctx->pipe;
2540 	struct child_prog *prog=ctx->child;
2541 
2542 	if (prog && prog->group == NULL
2543 		 && prog->argv == NULL
2544 #ifndef __U_BOOT__
2545 		 && prog->redirects == NULL) {
2546 #else
2547 										) {
2548 #endif
2549 		debug_printf("done_command: skipping null command\n");
2550 		return 0;
2551 	} else if (prog) {
2552 		pi->num_progs++;
2553 		debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2554 	} else {
2555 		debug_printf("done_command: initializing\n");
2556 	}
2557 	pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2558 
2559 	prog = pi->progs + pi->num_progs;
2560 #ifndef __U_BOOT__
2561 	prog->redirects = NULL;
2562 #endif
2563 	prog->argv = NULL;
2564 	prog->argv_nonnull = NULL;
2565 #ifndef __U_BOOT__
2566 	prog->is_stopped = 0;
2567 #endif
2568 	prog->group = NULL;
2569 #ifndef __U_BOOT__
2570 	prog->glob_result.gl_pathv = NULL;
2571 	prog->family = pi;
2572 #endif
2573 	prog->sp = 0;
2574 	ctx->child = prog;
2575 	prog->type = ctx->type;
2576 
2577 	/* but ctx->pipe and ctx->list_head remain unchanged */
2578 	return 0;
2579 }
2580 
2581 static int done_pipe(struct p_context *ctx, pipe_style type)
2582 {
2583 	struct pipe *new_p;
2584 	done_command(ctx);  /* implicit closure of previous command */
2585 	debug_printf("done_pipe, type %d\n", type);
2586 	ctx->pipe->followup = type;
2587 	ctx->pipe->r_mode = ctx->w;
2588 	new_p=new_pipe();
2589 	ctx->pipe->next = new_p;
2590 	ctx->pipe = new_p;
2591 	ctx->child = NULL;
2592 	done_command(ctx);  /* set up new pipe to accept commands */
2593 	return 0;
2594 }
2595 
2596 #ifndef __U_BOOT__
2597 /* peek ahead in the in_str to find out if we have a "&n" construct,
2598  * as in "2>&1", that represents duplicating a file descriptor.
2599  * returns either -2 (syntax error), -1 (no &), or the number found.
2600  */
2601 static int redirect_dup_num(struct in_str *input)
2602 {
2603 	int ch, d=0, ok=0;
2604 	ch = b_peek(input);
2605 	if (ch != '&') return -1;
2606 
2607 	b_getch(input);  /* get the & */
2608 	ch=b_peek(input);
2609 	if (ch == '-') {
2610 		b_getch(input);
2611 		return -3;  /* "-" represents "close me" */
2612 	}
2613 	while (isdigit(ch)) {
2614 		d = d*10+(ch-'0');
2615 		ok=1;
2616 		b_getch(input);
2617 		ch = b_peek(input);
2618 	}
2619 	if (ok) return d;
2620 
2621 	error_msg("ambiguous redirect");
2622 	return -2;
2623 }
2624 
2625 /* If a redirect is immediately preceded by a number, that number is
2626  * supposed to tell which file descriptor to redirect.  This routine
2627  * looks for such preceding numbers.  In an ideal world this routine
2628  * needs to handle all the following classes of redirects...
2629  *     echo 2>foo     # redirects fd  2 to file "foo", nothing passed to echo
2630  *     echo 49>foo    # redirects fd 49 to file "foo", nothing passed to echo
2631  *     echo -2>foo    # redirects fd  1 to file "foo",    "-2" passed to echo
2632  *     echo 49x>foo   # redirects fd  1 to file "foo",   "49x" passed to echo
2633  * A -1 output from this program means no valid number was found, so the
2634  * caller should use the appropriate default for this redirection.
2635  */
2636 static int redirect_opt_num(o_string *o)
2637 {
2638 	int num;
2639 
2640 	if (o->length==0) return -1;
2641 	for(num=0; num<o->length; num++) {
2642 		if (!isdigit(*(o->data+num))) {
2643 			return -1;
2644 		}
2645 	}
2646 	/* reuse num (and save an int) */
2647 	num=atoi(o->data);
2648 	b_reset(o);
2649 	return num;
2650 }
2651 
2652 FILE *generate_stream_from_list(struct pipe *head)
2653 {
2654 	FILE *pf;
2655 #if 1
2656 	int pid, channel[2];
2657 	if (pipe(channel)<0) perror_msg_and_die("pipe");
2658 	pid=fork();
2659 	if (pid<0) {
2660 		perror_msg_and_die("fork");
2661 	} else if (pid==0) {
2662 		close(channel[0]);
2663 		if (channel[1] != 1) {
2664 			dup2(channel[1],1);
2665 			close(channel[1]);
2666 		}
2667 #if 0
2668 #define SURROGATE "surrogate response"
2669 		write(1,SURROGATE,sizeof(SURROGATE));
2670 		_exit(run_list(head));
2671 #else
2672 		_exit(run_list_real(head));   /* leaks memory */
2673 #endif
2674 	}
2675 	debug_printf("forked child %d\n",pid);
2676 	close(channel[1]);
2677 	pf = fdopen(channel[0],"r");
2678 	debug_printf("pipe on FILE *%p\n",pf);
2679 #else
2680 	free_pipe_list(head,0);
2681 	pf=popen("echo surrogate response","r");
2682 	debug_printf("started fake pipe on FILE *%p\n",pf);
2683 #endif
2684 	return pf;
2685 }
2686 
2687 /* this version hacked for testing purposes */
2688 /* return code is exit status of the process that is run. */
2689 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2690 {
2691 	int retcode;
2692 	o_string result=NULL_O_STRING;
2693 	struct p_context inner;
2694 	FILE *p;
2695 	struct in_str pipe_str;
2696 	initialize_context(&inner);
2697 
2698 	/* recursion to generate command */
2699 	retcode = parse_stream(&result, &inner, input, subst_end);
2700 	if (retcode != 0) return retcode;  /* syntax error or EOF */
2701 	done_word(&result, &inner);
2702 	done_pipe(&inner, PIPE_SEQ);
2703 	b_free(&result);
2704 
2705 	p=generate_stream_from_list(inner.list_head);
2706 	if (p==NULL) return 1;
2707 	mark_open(fileno(p));
2708 	setup_file_in_str(&pipe_str, p);
2709 
2710 	/* now send results of command back into original context */
2711 	retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2712 	/* XXX In case of a syntax error, should we try to kill the child?
2713 	 * That would be tough to do right, so just read until EOF. */
2714 	if (retcode == 1) {
2715 		while (b_getch(&pipe_str)!=EOF) { /* discard */ };
2716 	}
2717 
2718 	debug_printf("done reading from pipe, pclose()ing\n");
2719 	/* This is the step that wait()s for the child.  Should be pretty
2720 	 * safe, since we just read an EOF from its stdout.  We could try
2721 	 * to better, by using wait(), and keeping track of background jobs
2722 	 * at the same time.  That would be a lot of work, and contrary
2723 	 * to the KISS philosophy of this program. */
2724 	mark_closed(fileno(p));
2725 	retcode=pclose(p);
2726 	free_pipe_list(inner.list_head,0);
2727 	debug_printf("pclosed, retcode=%d\n",retcode);
2728 	/* XXX this process fails to trim a single trailing newline */
2729 	return retcode;
2730 }
2731 
2732 static int parse_group(o_string *dest, struct p_context *ctx,
2733 	struct in_str *input, int ch)
2734 {
2735 	int rcode, endch=0;
2736 	struct p_context sub;
2737 	struct child_prog *child = ctx->child;
2738 	if (child->argv) {
2739 		syntax();
2740 		return 1;  /* syntax error, groups and arglists don't mix */
2741 	}
2742 	initialize_context(&sub);
2743 	switch(ch) {
2744 		case '(': endch=')'; child->subshell=1; break;
2745 		case '{': endch='}'; break;
2746 		default: syntax();   /* really logic error */
2747 	}
2748 	rcode=parse_stream(dest,&sub,input,endch);
2749 	done_word(dest,&sub); /* finish off the final word in the subcontext */
2750 	done_pipe(&sub, PIPE_SEQ);  /* and the final command there, too */
2751 	child->group = sub.list_head;
2752 	return rcode;
2753 	/* child remains "open", available for possible redirects */
2754 }
2755 #endif
2756 
2757 /* basically useful version until someone wants to get fancier,
2758  * see the bash man page under "Parameter Expansion" */
2759 static char *lookup_param(char *src)
2760 {
2761 	char *p;
2762 	char *sep;
2763 	char *default_val = NULL;
2764 	int assign = 0;
2765 	int expand_empty = 0;
2766 
2767 	if (!src)
2768 		return NULL;
2769 
2770 	sep = strchr(src, ':');
2771 
2772 	if (sep) {
2773 		*sep = '\0';
2774 		if (*(sep + 1) == '-')
2775 			default_val = sep+2;
2776 		if (*(sep + 1) == '=') {
2777 			default_val = sep+2;
2778 			assign = 1;
2779 		}
2780 		if (*(sep + 1) == '+') {
2781 			default_val = sep+2;
2782 			expand_empty = 1;
2783 		}
2784 	}
2785 
2786 	p = getenv(src);
2787 	if (!p)
2788 		p = get_local_var(src);
2789 
2790 	if (!p || strlen(p) == 0) {
2791 		p = default_val;
2792 		if (assign) {
2793 			char *var = malloc(strlen(src)+strlen(default_val)+2);
2794 			if (var) {
2795 				sprintf(var, "%s=%s", src, default_val);
2796 				set_local_var(var, 0);
2797 			}
2798 			free(var);
2799 		}
2800 	} else if (expand_empty) {
2801 		p += strlen(p);
2802 	}
2803 
2804 	if (sep)
2805 		*sep = ':';
2806 
2807 	return p;
2808 }
2809 
2810 #ifdef __U_BOOT__
2811 static char *get_dollar_var(char ch)
2812 {
2813 	static char buf[40];
2814 
2815 	buf[0] = '\0';
2816 	switch (ch) {
2817 		case '?':
2818 			sprintf(buf, "%u", (unsigned int)last_return_code);
2819 			break;
2820 		default:
2821 			return NULL;
2822 	}
2823 	return buf;
2824 }
2825 #endif
2826 
2827 /* return code: 0 for OK, 1 for syntax error */
2828 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2829 {
2830 #ifndef __U_BOOT__
2831 	int i, advance=0;
2832 #else
2833 	int advance=0;
2834 #endif
2835 #ifndef __U_BOOT__
2836 	char sep[]=" ";
2837 #endif
2838 	int ch = input->peek(input);  /* first character after the $ */
2839 	debug_printf("handle_dollar: ch=%c\n",ch);
2840 	if (isalpha(ch)) {
2841 		b_addchr(dest, SPECIAL_VAR_SYMBOL);
2842 		ctx->child->sp++;
2843 		while(ch=b_peek(input),isalnum(ch) || ch=='_') {
2844 			b_getch(input);
2845 			b_addchr(dest,ch);
2846 		}
2847 		b_addchr(dest, SPECIAL_VAR_SYMBOL);
2848 #ifndef __U_BOOT__
2849 	} else if (isdigit(ch)) {
2850 		i = ch-'0';  /* XXX is $0 special? */
2851 		if (i<global_argc) {
2852 			parse_string(dest, ctx, global_argv[i]); /* recursion */
2853 		}
2854 		advance = 1;
2855 #endif
2856 	} else switch (ch) {
2857 #ifndef __U_BOOT__
2858 		case '$':
2859 			b_adduint(dest,getpid());
2860 			advance = 1;
2861 			break;
2862 		case '!':
2863 			if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2864 			advance = 1;
2865 			break;
2866 #endif
2867 		case '?':
2868 #ifndef __U_BOOT__
2869 			b_adduint(dest,last_return_code);
2870 #else
2871 			ctx->child->sp++;
2872 			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2873 			b_addchr(dest, '$');
2874 			b_addchr(dest, '?');
2875 			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2876 #endif
2877 			advance = 1;
2878 			break;
2879 #ifndef __U_BOOT__
2880 		case '#':
2881 			b_adduint(dest,global_argc ? global_argc-1 : 0);
2882 			advance = 1;
2883 			break;
2884 #endif
2885 		case '{':
2886 			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2887 			ctx->child->sp++;
2888 			b_getch(input);
2889 			/* XXX maybe someone will try to escape the '}' */
2890 			while(ch=b_getch(input),ch!=EOF && ch!='}') {
2891 				b_addchr(dest,ch);
2892 			}
2893 			if (ch != '}') {
2894 				syntax();
2895 				return 1;
2896 			}
2897 			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2898 			break;
2899 #ifndef __U_BOOT__
2900 		case '(':
2901 			b_getch(input);
2902 			process_command_subs(dest, ctx, input, ')');
2903 			break;
2904 		case '*':
2905 			sep[0]=ifs[0];
2906 			for (i=1; i<global_argc; i++) {
2907 				parse_string(dest, ctx, global_argv[i]);
2908 				if (i+1 < global_argc) parse_string(dest, ctx, sep);
2909 			}
2910 			break;
2911 		case '@':
2912 		case '-':
2913 		case '_':
2914 			/* still unhandled, but should be eventually */
2915 			error_msg("unhandled syntax: $%c",ch);
2916 			return 1;
2917 			break;
2918 #endif
2919 		default:
2920 			b_addqchr(dest,'$',dest->quote);
2921 	}
2922 	/* Eat the character if the flag was set.  If the compiler
2923 	 * is smart enough, we could substitute "b_getch(input);"
2924 	 * for all the "advance = 1;" above, and also end up with
2925 	 * a nice size-optimized program.  Hah!  That'll be the day.
2926 	 */
2927 	if (advance) b_getch(input);
2928 	return 0;
2929 }
2930 
2931 #ifndef __U_BOOT__
2932 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2933 {
2934 	struct in_str foo;
2935 	setup_string_in_str(&foo, src);
2936 	return parse_stream(dest, ctx, &foo, '\0');
2937 }
2938 #endif
2939 
2940 /* return code is 0 for normal exit, 1 for syntax error */
2941 static int parse_stream(o_string *dest, struct p_context *ctx,
2942 			struct in_str *input, int end_trigger)
2943 {
2944 	unsigned int ch, m;
2945 #ifndef __U_BOOT__
2946 	int redir_fd;
2947 	redir_type redir_style;
2948 #endif
2949 	int next;
2950 
2951 	/* Only double-quote state is handled in the state variable dest->quote.
2952 	 * A single-quote triggers a bypass of the main loop until its mate is
2953 	 * found.  When recursing, quote state is passed in via dest->quote. */
2954 
2955 	debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2956 	while ((ch=b_getch(input))!=EOF) {
2957 		m = map[ch];
2958 #ifdef __U_BOOT__
2959 		if (input->__promptme == 0) return 1;
2960 #endif
2961 		next = (ch == '\n') ? 0 : b_peek(input);
2962 
2963 		debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d - %c\n",
2964 			ch >= ' ' ? ch : '.', ch, m,
2965 			dest->quote, ctx->stack == NULL ? '*' : '.');
2966 
2967 		if (m==0 || ((m==1 || m==2) && dest->quote)) {
2968 			b_addqchr(dest, ch, dest->quote);
2969 		} else {
2970 			if (m==2) {  /* unquoted IFS */
2971 				if (done_word(dest, ctx)) {
2972 					return 1;
2973 				}
2974 				/* If we aren't performing a substitution, treat a newline as a
2975 				 * command separator.  */
2976 				if (end_trigger != '\0' && ch=='\n')
2977 					done_pipe(ctx,PIPE_SEQ);
2978 			}
2979 			if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2980 				debug_printf("leaving parse_stream (triggered)\n");
2981 				return 0;
2982 			}
2983 #if 0
2984 			if (ch=='\n') {
2985 				/* Yahoo!  Time to run with it! */
2986 				done_pipe(ctx,PIPE_SEQ);
2987 				run_list(ctx->list_head);
2988 				initialize_context(ctx);
2989 			}
2990 #endif
2991 			if (m!=2) switch (ch) {
2992 		case '#':
2993 			if (dest->length == 0 && !dest->quote) {
2994 				while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
2995 			} else {
2996 				b_addqchr(dest, ch, dest->quote);
2997 			}
2998 			break;
2999 		case '\\':
3000 			if (next == EOF) {
3001 				syntax();
3002 				return 1;
3003 			}
3004 			b_addqchr(dest, '\\', dest->quote);
3005 			b_addqchr(dest, b_getch(input), dest->quote);
3006 			break;
3007 		case '$':
3008 			if (handle_dollar(dest, ctx, input)!=0) return 1;
3009 			break;
3010 		case '\'':
3011 			dest->nonnull = 1;
3012 			while(ch=b_getch(input),ch!=EOF && ch!='\'') {
3013 #ifdef __U_BOOT__
3014 				if(input->__promptme == 0) return 1;
3015 #endif
3016 				b_addchr(dest,ch);
3017 			}
3018 			if (ch==EOF) {
3019 				syntax();
3020 				return 1;
3021 			}
3022 			break;
3023 		case '"':
3024 			dest->nonnull = 1;
3025 			dest->quote = !dest->quote;
3026 			break;
3027 #ifndef __U_BOOT__
3028 		case '`':
3029 			process_command_subs(dest, ctx, input, '`');
3030 			break;
3031 		case '>':
3032 			redir_fd = redirect_opt_num(dest);
3033 			done_word(dest, ctx);
3034 			redir_style=REDIRECT_OVERWRITE;
3035 			if (next == '>') {
3036 				redir_style=REDIRECT_APPEND;
3037 				b_getch(input);
3038 			} else if (next == '(') {
3039 				syntax();   /* until we support >(list) Process Substitution */
3040 				return 1;
3041 			}
3042 			setup_redirect(ctx, redir_fd, redir_style, input);
3043 			break;
3044 		case '<':
3045 			redir_fd = redirect_opt_num(dest);
3046 			done_word(dest, ctx);
3047 			redir_style=REDIRECT_INPUT;
3048 			if (next == '<') {
3049 				redir_style=REDIRECT_HEREIS;
3050 				b_getch(input);
3051 			} else if (next == '>') {
3052 				redir_style=REDIRECT_IO;
3053 				b_getch(input);
3054 			} else if (next == '(') {
3055 				syntax();   /* until we support <(list) Process Substitution */
3056 				return 1;
3057 			}
3058 			setup_redirect(ctx, redir_fd, redir_style, input);
3059 			break;
3060 #endif
3061 		case ';':
3062 			done_word(dest, ctx);
3063 			done_pipe(ctx,PIPE_SEQ);
3064 			break;
3065 		case '&':
3066 			done_word(dest, ctx);
3067 			if (next=='&') {
3068 				b_getch(input);
3069 				done_pipe(ctx,PIPE_AND);
3070 			} else {
3071 #ifndef __U_BOOT__
3072 				done_pipe(ctx,PIPE_BG);
3073 #else
3074 				syntax_err();
3075 				return 1;
3076 #endif
3077 			}
3078 			break;
3079 		case '|':
3080 			done_word(dest, ctx);
3081 			if (next=='|') {
3082 				b_getch(input);
3083 				done_pipe(ctx,PIPE_OR);
3084 			} else {
3085 				/* we could pick up a file descriptor choice here
3086 				 * with redirect_opt_num(), but bash doesn't do it.
3087 				 * "echo foo 2| cat" yields "foo 2". */
3088 #ifndef __U_BOOT__
3089 				done_command(ctx);
3090 #else
3091 				syntax_err();
3092 				return 1;
3093 #endif
3094 			}
3095 			break;
3096 #ifndef __U_BOOT__
3097 		case '(':
3098 		case '{':
3099 			if (parse_group(dest, ctx, input, ch)!=0) return 1;
3100 			break;
3101 		case ')':
3102 		case '}':
3103 			syntax();   /* Proper use of this character caught by end_trigger */
3104 			return 1;
3105 			break;
3106 #endif
3107 		case SUBSTED_VAR_SYMBOL:
3108 			dest->nonnull = 1;
3109 			while (ch = b_getch(input), ch != EOF &&
3110 			    ch != SUBSTED_VAR_SYMBOL) {
3111 				debug_printf("subst, pass=%d\n", ch);
3112 				if (input->__promptme == 0)
3113 					return 1;
3114 				b_addchr(dest, ch);
3115 			}
3116 			debug_printf("subst, term=%d\n", ch);
3117 			if (ch == EOF) {
3118 				syntax();
3119 				return 1;
3120 			}
3121 			break;
3122 		default:
3123 			syntax();   /* this is really an internal logic error */
3124 			return 1;
3125 			}
3126 		}
3127 	}
3128 	/* complain if quote?  No, maybe we just finished a command substitution
3129 	 * that was quoted.  Example:
3130 	 * $ echo "`cat foo` plus more"
3131 	 * and we just got the EOF generated by the subshell that ran "cat foo"
3132 	 * The only real complaint is if we got an EOF when end_trigger != '\0',
3133 	 * that is, we were really supposed to get end_trigger, and never got
3134 	 * one before the EOF.  Can't use the standard "syntax error" return code,
3135 	 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
3136 	debug_printf("leaving parse_stream (EOF)\n");
3137 	if (end_trigger != '\0') return -1;
3138 	return 0;
3139 }
3140 
3141 static void mapset(const unsigned char *set, int code)
3142 {
3143 	const unsigned char *s;
3144 	for (s=set; *s; s++) map[*s] = code;
3145 }
3146 
3147 static void update_ifs_map(void)
3148 {
3149 	/* char *ifs and char map[256] are both globals. */
3150 	ifs = (uchar *)getenv("IFS");
3151 	if (ifs == NULL) ifs=(uchar *)" \t\n";
3152 	/* Precompute a list of 'flow through' behavior so it can be treated
3153 	 * quickly up front.  Computation is necessary because of IFS.
3154 	 * Special case handling of IFS == " \t\n" is not implemented.
3155 	 * The map[] array only really needs two bits each, and on most machines
3156 	 * that would be faster because of the reduced L1 cache footprint.
3157 	 */
3158 	memset(map,0,sizeof(map)); /* most characters flow through always */
3159 #ifndef __U_BOOT__
3160 	mapset((uchar *)"\\$'\"`", 3);      /* never flow through */
3161 	mapset((uchar *)"<>;&|(){}#", 1);   /* flow through if quoted */
3162 #else
3163 	{
3164 		uchar subst[2] = {SUBSTED_VAR_SYMBOL, 0};
3165 		mapset(subst, 3);       /* never flow through */
3166 	}
3167 	mapset((uchar *)"\\$'\"", 3);       /* never flow through */
3168 	mapset((uchar *)";&|#", 1);         /* flow through if quoted */
3169 #endif
3170 	mapset(ifs, 2);            /* also flow through if quoted */
3171 }
3172 
3173 /* most recursion does not come through here, the exeception is
3174  * from builtin_source() */
3175 static int parse_stream_outer(struct in_str *inp, int flag)
3176 {
3177 
3178 	struct p_context ctx;
3179 	o_string temp=NULL_O_STRING;
3180 	int rcode;
3181 #ifdef __U_BOOT__
3182 	int code = 1;
3183 #endif
3184 	do {
3185 		ctx.type = flag;
3186 		initialize_context(&ctx);
3187 		update_ifs_map();
3188 		if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset((uchar *)";$&|", 0);
3189 		inp->promptmode=1;
3190 		rcode = parse_stream(&temp, &ctx, inp,
3191 				     flag & FLAG_CONT_ON_NEWLINE ? -1 : '\n');
3192 #ifdef __U_BOOT__
3193 		if (rcode == 1) flag_repeat = 0;
3194 #endif
3195 		if (rcode != 1 && ctx.old_flag != 0) {
3196 			syntax();
3197 #ifdef __U_BOOT__
3198 			flag_repeat = 0;
3199 #endif
3200 		}
3201 		if (rcode != 1 && ctx.old_flag == 0) {
3202 			done_word(&temp, &ctx);
3203 			done_pipe(&ctx,PIPE_SEQ);
3204 #ifndef __U_BOOT__
3205 			run_list(ctx.list_head);
3206 #else
3207 			code = run_list(ctx.list_head);
3208 			if (code == -2) {	/* exit */
3209 				b_free(&temp);
3210 				code = 0;
3211 				/* XXX hackish way to not allow exit from main loop */
3212 				if (inp->peek == file_peek) {
3213 					printf("exit not allowed from main input shell.\n");
3214 					continue;
3215 				}
3216 				break;
3217 			}
3218 			if (code == -1)
3219 			    flag_repeat = 0;
3220 #endif
3221 		} else {
3222 			if (ctx.old_flag != 0) {
3223 				free(ctx.stack);
3224 				b_reset(&temp);
3225 			}
3226 #ifdef __U_BOOT__
3227 			if (inp->__promptme == 0) printf("<INTERRUPT>\n");
3228 			inp->__promptme = 1;
3229 #endif
3230 			temp.nonnull = 0;
3231 			temp.quote = 0;
3232 			inp->p = NULL;
3233 			free_pipe_list(ctx.list_head,0);
3234 		}
3235 		b_free(&temp);
3236 	/* loop on syntax errors, return on EOF */
3237 	} while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP) &&
3238 		(inp->peek != static_peek || b_peek(inp)));
3239 #ifndef __U_BOOT__
3240 	return 0;
3241 #else
3242 	return (code != 0) ? 1 : 0;
3243 #endif /* __U_BOOT__ */
3244 }
3245 
3246 #ifndef __U_BOOT__
3247 static int parse_string_outer(const char *s, int flag)
3248 #else
3249 int parse_string_outer(const char *s, int flag)
3250 #endif	/* __U_BOOT__ */
3251 {
3252 	struct in_str input;
3253 #ifdef __U_BOOT__
3254 	char *p = NULL;
3255 	int rcode;
3256 	if (!s)
3257 		return 1;
3258 	if (!*s)
3259 		return 0;
3260 	if (!(p = strchr(s, '\n')) || *++p) {
3261 		p = xmalloc(strlen(s) + 2);
3262 		strcpy(p, s);
3263 		strcat(p, "\n");
3264 		setup_string_in_str(&input, p);
3265 		rcode = parse_stream_outer(&input, flag);
3266 		free(p);
3267 		return rcode;
3268 	} else {
3269 #endif
3270 	setup_string_in_str(&input, s);
3271 	return parse_stream_outer(&input, flag);
3272 #ifdef __U_BOOT__
3273 	}
3274 #endif
3275 }
3276 
3277 #ifndef __U_BOOT__
3278 static int parse_file_outer(FILE *f)
3279 #else
3280 int parse_file_outer(void)
3281 #endif
3282 {
3283 	int rcode;
3284 	struct in_str input;
3285 #ifndef __U_BOOT__
3286 	setup_file_in_str(&input, f);
3287 #else
3288 	setup_file_in_str(&input);
3289 #endif
3290 	rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
3291 	return rcode;
3292 }
3293 
3294 #ifdef __U_BOOT__
3295 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3296 static void u_boot_hush_reloc(void)
3297 {
3298 	unsigned long addr;
3299 	struct reserved_combo *r;
3300 
3301 	for (r=reserved_list; r<reserved_list+NRES; r++) {
3302 		addr = (ulong) (r->literal) + gd->reloc_off;
3303 		r->literal = (char *)addr;
3304 	}
3305 }
3306 #endif
3307 
3308 int u_boot_hush_start(void)
3309 {
3310 	if (top_vars == NULL) {
3311 		top_vars = malloc(sizeof(struct variables));
3312 		top_vars->name = "HUSH_VERSION";
3313 		top_vars->value = "0.01";
3314 		top_vars->next = NULL;
3315 		top_vars->flg_export = 0;
3316 		top_vars->flg_read_only = 1;
3317 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3318 		u_boot_hush_reloc();
3319 #endif
3320 	}
3321 	return 0;
3322 }
3323 
3324 static void *xmalloc(size_t size)
3325 {
3326 	void *p = NULL;
3327 
3328 	if (!(p = malloc(size))) {
3329 	    printf("ERROR : memory not allocated\n");
3330 	    for(;;);
3331 	}
3332 	return p;
3333 }
3334 
3335 static void *xrealloc(void *ptr, size_t size)
3336 {
3337 	void *p = NULL;
3338 
3339 	if (!(p = realloc(ptr, size))) {
3340 	    printf("ERROR : memory not allocated\n");
3341 	    for(;;);
3342 	}
3343 	return p;
3344 }
3345 #endif /* __U_BOOT__ */
3346 
3347 #ifndef __U_BOOT__
3348 /* Make sure we have a controlling tty.  If we get started under a job
3349  * aware app (like bash for example), make sure we are now in charge so
3350  * we don't fight over who gets the foreground */
3351 static void setup_job_control(void)
3352 {
3353 	static pid_t shell_pgrp;
3354 	/* Loop until we are in the foreground.  */
3355 	while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
3356 		kill (- shell_pgrp, SIGTTIN);
3357 
3358 	/* Ignore interactive and job-control signals.  */
3359 	signal(SIGINT, SIG_IGN);
3360 	signal(SIGQUIT, SIG_IGN);
3361 	signal(SIGTERM, SIG_IGN);
3362 	signal(SIGTSTP, SIG_IGN);
3363 	signal(SIGTTIN, SIG_IGN);
3364 	signal(SIGTTOU, SIG_IGN);
3365 	signal(SIGCHLD, SIG_IGN);
3366 
3367 	/* Put ourselves in our own process group.  */
3368 	setsid();
3369 	shell_pgrp = getpid ();
3370 	setpgid (shell_pgrp, shell_pgrp);
3371 
3372 	/* Grab control of the terminal.  */
3373 	tcsetpgrp(shell_terminal, shell_pgrp);
3374 }
3375 
3376 int hush_main(int argc, char * const *argv)
3377 {
3378 	int opt;
3379 	FILE *input;
3380 	char **e = environ;
3381 
3382 	/* XXX what should these be while sourcing /etc/profile? */
3383 	global_argc = argc;
3384 	global_argv = argv;
3385 
3386 	/* (re?) initialize globals.  Sometimes hush_main() ends up calling
3387 	 * hush_main(), therefore we cannot rely on the BSS to zero out this
3388 	 * stuff.  Reset these to 0 every time. */
3389 	ifs = NULL;
3390 	/* map[] is taken care of with call to update_ifs_map() */
3391 	fake_mode = 0;
3392 	interactive = 0;
3393 	close_me_head = NULL;
3394 	last_bg_pid = 0;
3395 	job_list = NULL;
3396 	last_jobid = 0;
3397 
3398 	/* Initialize some more globals to non-zero values */
3399 	set_cwd();
3400 #ifdef CONFIG_FEATURE_COMMAND_EDITING
3401 	cmdedit_set_initial_prompt();
3402 #else
3403 	PS1 = NULL;
3404 #endif
3405 	PS2 = "> ";
3406 
3407 	/* initialize our shell local variables with the values
3408 	 * currently living in the environment */
3409 	if (e) {
3410 		for (; *e; e++)
3411 			set_local_var(*e, 2);   /* without call putenv() */
3412 	}
3413 
3414 	last_return_code=EXIT_SUCCESS;
3415 
3416 
3417 	if (argv[0] && argv[0][0] == '-') {
3418 		debug_printf("\nsourcing /etc/profile\n");
3419 		if ((input = fopen("/etc/profile", "r")) != NULL) {
3420 			mark_open(fileno(input));
3421 			parse_file_outer(input);
3422 			mark_closed(fileno(input));
3423 			fclose(input);
3424 		}
3425 	}
3426 	input=stdin;
3427 
3428 	while ((opt = getopt(argc, argv, "c:xif")) > 0) {
3429 		switch (opt) {
3430 			case 'c':
3431 				{
3432 					global_argv = argv+optind;
3433 					global_argc = argc-optind;
3434 					opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
3435 					goto final_return;
3436 				}
3437 				break;
3438 			case 'i':
3439 				interactive++;
3440 				break;
3441 			case 'f':
3442 				fake_mode++;
3443 				break;
3444 			default:
3445 #ifndef BB_VER
3446 				fprintf(stderr, "Usage: sh [FILE]...\n"
3447 						"   or: sh -c command [args]...\n\n");
3448 				exit(EXIT_FAILURE);
3449 #else
3450 				show_usage();
3451 #endif
3452 		}
3453 	}
3454 	/* A shell is interactive if the `-i' flag was given, or if all of
3455 	 * the following conditions are met:
3456 	 *	  no -c command
3457 	 *    no arguments remaining or the -s flag given
3458 	 *    standard input is a terminal
3459 	 *    standard output is a terminal
3460 	 *    Refer to Posix.2, the description of the `sh' utility. */
3461 	if (argv[optind]==NULL && input==stdin &&
3462 			isatty(fileno(stdin)) && isatty(fileno(stdout))) {
3463 		interactive++;
3464 	}
3465 
3466 	debug_printf("\ninteractive=%d\n", interactive);
3467 	if (interactive) {
3468 		/* Looks like they want an interactive shell */
3469 #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
3470 		printf( "\n\n" BB_BANNER " hush - the humble shell v0.01 (testing)\n");
3471 		printf( "Enter 'help' for a list of built-in commands.\n\n");
3472 #endif
3473 		setup_job_control();
3474 	}
3475 
3476 	if (argv[optind]==NULL) {
3477 		opt=parse_file_outer(stdin);
3478 		goto final_return;
3479 	}
3480 
3481 	debug_printf("\nrunning script '%s'\n", argv[optind]);
3482 	global_argv = argv+optind;
3483 	global_argc = argc-optind;
3484 	input = xfopen(argv[optind], "r");
3485 	opt = parse_file_outer(input);
3486 
3487 #ifdef CONFIG_FEATURE_CLEAN_UP
3488 	fclose(input);
3489 	if (cwd && cwd != unknown)
3490 		free((char*)cwd);
3491 	{
3492 		struct variables *cur, *tmp;
3493 		for(cur = top_vars; cur; cur = tmp) {
3494 			tmp = cur->next;
3495 			if (!cur->flg_read_only) {
3496 				free(cur->name);
3497 				free(cur->value);
3498 				free(cur);
3499 			}
3500 		}
3501 	}
3502 #endif
3503 
3504 final_return:
3505 	return(opt?opt:last_return_code);
3506 }
3507 #endif
3508 
3509 static char *insert_var_value(char *inp)
3510 {
3511 	return insert_var_value_sub(inp, 0);
3512 }
3513 
3514 static char *insert_var_value_sub(char *inp, int tag_subst)
3515 {
3516 	int res_str_len = 0;
3517 	int len;
3518 	int done = 0;
3519 	char *p, *p1, *res_str = NULL;
3520 
3521 	while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
3522 		/* check the beginning of the string for normal characters */
3523 		if (p != inp) {
3524 			/* copy any characters to the result string */
3525 			len = p - inp;
3526 			res_str = xrealloc(res_str, (res_str_len + len));
3527 			strncpy((res_str + res_str_len), inp, len);
3528 			res_str_len += len;
3529 		}
3530 		inp = ++p;
3531 		/* find the ending marker */
3532 		p = strchr(inp, SPECIAL_VAR_SYMBOL);
3533 		*p = '\0';
3534 		/* look up the value to substitute */
3535 		if ((p1 = lookup_param(inp))) {
3536 			if (tag_subst)
3537 				len = res_str_len + strlen(p1) + 2;
3538 			else
3539 				len = res_str_len + strlen(p1);
3540 			res_str = xrealloc(res_str, (1 + len));
3541 			if (tag_subst) {
3542 				/*
3543 				 * copy the variable value to the result
3544 				 * string
3545 				 */
3546 				strcpy((res_str + res_str_len + 1), p1);
3547 
3548 				/*
3549 				 * mark the replaced text to be accepted as
3550 				 * is
3551 				 */
3552 				res_str[res_str_len] = SUBSTED_VAR_SYMBOL;
3553 				res_str[res_str_len + 1 + strlen(p1)] =
3554 					SUBSTED_VAR_SYMBOL;
3555 			} else
3556 				/*
3557 				 * copy the variable value to the result
3558 				 * string
3559 				 */
3560 				strcpy((res_str + res_str_len), p1);
3561 
3562 			res_str_len = len;
3563 		}
3564 		*p = SPECIAL_VAR_SYMBOL;
3565 		inp = ++p;
3566 		done = 1;
3567 	}
3568 	if (done) {
3569 		res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
3570 		strcpy((res_str + res_str_len), inp);
3571 		while ((p = strchr(res_str, '\n'))) {
3572 			*p = ' ';
3573 		}
3574 	}
3575 	return (res_str == NULL) ? inp : res_str;
3576 }
3577 
3578 static char **make_list_in(char **inp, char *name)
3579 {
3580 	int len, i;
3581 	int name_len = strlen(name);
3582 	int n = 0;
3583 	char **list;
3584 	char *p1, *p2, *p3;
3585 
3586 	/* create list of variable values */
3587 	list = xmalloc(sizeof(*list));
3588 	for (i = 0; inp[i]; i++) {
3589 		p3 = insert_var_value(inp[i]);
3590 		p1 = p3;
3591 		while (*p1) {
3592 			if (*p1 == ' ') {
3593 				p1++;
3594 				continue;
3595 			}
3596 			if ((p2 = strchr(p1, ' '))) {
3597 				len = p2 - p1;
3598 			} else {
3599 				len = strlen(p1);
3600 				p2 = p1 + len;
3601 			}
3602 			/* we use n + 2 in realloc for list,because we add
3603 			 * new element and then we will add NULL element */
3604 			list = xrealloc(list, sizeof(*list) * (n + 2));
3605 			list[n] = xmalloc(2 + name_len + len);
3606 			strcpy(list[n], name);
3607 			strcat(list[n], "=");
3608 			strncat(list[n], p1, len);
3609 			list[n++][name_len + len + 1] = '\0';
3610 			p1 = p2;
3611 		}
3612 		if (p3 != inp[i]) free(p3);
3613 	}
3614 	list[n] = NULL;
3615 	return list;
3616 }
3617 
3618 /*
3619  * Make new string for parser
3620  * inp     - array of argument strings to flatten
3621  * nonnull - indicates argument was quoted when originally parsed
3622  */
3623 static char *make_string(char **inp, int *nonnull)
3624 {
3625 	char *p;
3626 	char *str = NULL;
3627 	int n;
3628 	int len = 2;
3629 	char *noeval_str;
3630 	int noeval = 0;
3631 
3632 	noeval_str = get_local_var("HUSH_NO_EVAL");
3633 	if (noeval_str != NULL && *noeval_str != '0' && *noeval_str != '\0')
3634 		noeval = 1;
3635 	for (n = 0; inp[n]; n++) {
3636 		p = insert_var_value_sub(inp[n], noeval);
3637 		str = xrealloc(str, (len + strlen(p) + (2 * nonnull[n])));
3638 		if (n) {
3639 			strcat(str, " ");
3640 		} else {
3641 			*str = '\0';
3642 		}
3643 		if (nonnull[n])
3644 			strcat(str, "'");
3645 		strcat(str, p);
3646 		if (nonnull[n])
3647 			strcat(str, "'");
3648 		len = strlen(str) + 3;
3649 		if (p != inp[n]) free(p);
3650 	}
3651 	len = strlen(str);
3652 	*(str + len) = '\n';
3653 	*(str + len + 1) = '\0';
3654 	return str;
3655 }
3656 
3657 #ifdef __U_BOOT__
3658 static int do_showvar(cmd_tbl_t *cmdtp, int flag, int argc,
3659 		      char * const argv[])
3660 {
3661 	int i, k;
3662 	int rcode = 0;
3663 	struct variables *cur;
3664 
3665 	if (argc == 1) {		/* Print all env variables	*/
3666 		for (cur = top_vars; cur; cur = cur->next) {
3667 			printf ("%s=%s\n", cur->name, cur->value);
3668 			if (ctrlc ()) {
3669 				puts ("\n ** Abort\n");
3670 				return 1;
3671 			}
3672 		}
3673 		return 0;
3674 	}
3675 	for (i = 1; i < argc; ++i) {	/* print single env variables	*/
3676 		char *name = argv[i];
3677 
3678 		k = -1;
3679 		for (cur = top_vars; cur; cur = cur->next) {
3680 			if(strcmp (cur->name, name) == 0) {
3681 				k = 0;
3682 				printf ("%s=%s\n", cur->name, cur->value);
3683 			}
3684 			if (ctrlc ()) {
3685 				puts ("\n ** Abort\n");
3686 				return 1;
3687 			}
3688 		}
3689 		if (k < 0) {
3690 			printf ("## Error: \"%s\" not defined\n", name);
3691 			rcode ++;
3692 		}
3693 	}
3694 	return rcode;
3695 }
3696 
3697 U_BOOT_CMD(
3698 	showvar, CONFIG_SYS_MAXARGS, 1,	do_showvar,
3699 	"print local hushshell variables",
3700 	"\n    - print values of all hushshell variables\n"
3701 	"showvar name ...\n"
3702 	"    - print value of hushshell variable 'name'"
3703 );
3704 
3705 #endif
3706 /****************************************************************************/
3707