xref: /openbmc/u-boot/common/cli_hush.c (revision 83d290c56fab2d38cd1ab4c4cc7099559c1d5046)
1  // SPDX-License-Identifier: GPL-2.0+
2  /*
3   * sh.c -- a prototype Bourne shell grammar parser
4   *      Intended to follow the original Thompson and Ritchie
5   *      "small and simple is beautiful" philosophy, which
6   *      incidentally is a good match to today's BusyBox.
7   *
8   * Copyright (C) 2000,2001  Larry Doolittle  <larry@doolittle.boa.org>
9   *
10   * Credits:
11   *      The parser routines proper are all original material, first
12   *      written Dec 2000 and Jan 2001 by Larry Doolittle.
13   *      The execution engine, the builtins, and much of the underlying
14   *      support has been adapted from busybox-0.49pre's lash,
15   *      which is Copyright (C) 2000 by Lineo, Inc., and
16   *      written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>.
17   *      That, in turn, is based in part on ladsh.c, by Michael K. Johnson and
18   *      Erik W. Troan, which they placed in the public domain.  I don't know
19   *      how much of the Johnson/Troan code has survived the repeated rewrites.
20   * Other credits:
21   *      b_addchr() derived from similar w_addchar function in glibc-2.2
22   *      setup_redirect(), redirect_opt_num(), and big chunks of main()
23   *        and many builtins derived from contributions by Erik Andersen
24   *      miscellaneous bugfixes from Matt Kraai
25   *
26   * There are two big (and related) architecture differences between
27   * this parser and the lash parser.  One is that this version is
28   * actually designed from the ground up to understand nearly all
29   * of the Bourne grammar.  The second, consequential change is that
30   * the parser and input reader have been turned inside out.  Now,
31   * the parser is in control, and asks for input as needed.  The old
32   * way had the input reader in control, and it asked for parsing to
33   * take place as needed.  The new way makes it much easier to properly
34   * handle the recursion implicit in the various substitutions, especially
35   * across continuation lines.
36   *
37   * Bash grammar not implemented: (how many of these were in original sh?)
38   *      $@ (those sure look like weird quoting rules)
39   *      $_
40   *      ! negation operator for pipes
41   *      &> and >& redirection of stdout+stderr
42   *      Brace Expansion
43   *      Tilde Expansion
44   *      fancy forms of Parameter Expansion
45   *      aliases
46   *      Arithmetic Expansion
47   *      <(list) and >(list) Process Substitution
48   *      reserved words: case, esac, select, function
49   *      Here Documents ( << word )
50   *      Functions
51   * Major bugs:
52   *      job handling woefully incomplete and buggy
53   *      reserved word execution woefully incomplete and buggy
54   * to-do:
55   *      port selected bugfixes from post-0.49 busybox lash - done?
56   *      finish implementing reserved words: for, while, until, do, done
57   *      change { and } from special chars to reserved words
58   *      builtins: break, continue, eval, return, set, trap, ulimit
59   *      test magic exec
60   *      handle children going into background
61   *      clean up recognition of null pipes
62   *      check setting of global_argc and global_argv
63   *      control-C handling, probably with longjmp
64   *      follow IFS rules more precisely, including update semantics
65   *      figure out what to do with backslash-newline
66   *      explain why we use signal instead of sigaction
67   *      propagate syntax errors, die on resource errors?
68   *      continuation lines, both explicit and implicit - done?
69   *      memory leak finding and plugging - done?
70   *      more testing, especially quoting rules and redirection
71   *      document how quoting rules not precisely followed for variable assignments
72   *      maybe change map[] to use 2-bit entries
73   *      (eventually) remove all the printf's
74   */
75  
76  #define __U_BOOT__
77  #ifdef __U_BOOT__
78  #include <malloc.h>         /* malloc, free, realloc*/
79  #include <linux/ctype.h>    /* isalpha, isdigit */
80  #include <common.h>        /* readline */
81  #include <console.h>
82  #include <bootretry.h>
83  #include <cli.h>
84  #include <cli_hush.h>
85  #include <command.h>        /* find_cmd */
86  #ifndef CONFIG_SYS_PROMPT_HUSH_PS2
87  #define CONFIG_SYS_PROMPT_HUSH_PS2	"> "
88  #endif
89  #endif
90  #ifndef __U_BOOT__
91  #include <ctype.h>     /* isalpha, isdigit */
92  #include <unistd.h>    /* getpid */
93  #include <stdlib.h>    /* getenv, atoi */
94  #include <string.h>    /* strchr */
95  #include <stdio.h>     /* popen etc. */
96  #include <glob.h>      /* glob, of course */
97  #include <stdarg.h>    /* va_list */
98  #include <errno.h>
99  #include <fcntl.h>
100  #include <getopt.h>    /* should be pretty obvious */
101  
102  #include <sys/stat.h>  /* ulimit */
103  #include <sys/types.h>
104  #include <sys/wait.h>
105  #include <signal.h>
106  
107  /* #include <dmalloc.h> */
108  
109  #if 1
110  #include "busybox.h"
111  #include "cmdedit.h"
112  #else
113  #define applet_name "hush"
114  #include "standalone.h"
115  #define hush_main main
116  #undef CONFIG_FEATURE_SH_FANCY_PROMPT
117  #define BB_BANNER
118  #endif
119  #endif
120  #define SPECIAL_VAR_SYMBOL 03
121  #define SUBSTED_VAR_SYMBOL 04
122  #ifndef __U_BOOT__
123  #define FLAG_EXIT_FROM_LOOP 1
124  #define FLAG_PARSE_SEMICOLON (1 << 1)		/* symbol ';' is special for parser */
125  #define FLAG_REPARSING       (1 << 2)		/* >= 2nd pass */
126  
127  #endif
128  
129  #ifdef __U_BOOT__
130  DECLARE_GLOBAL_DATA_PTR;
131  
132  #define EXIT_SUCCESS 0
133  #define EOF -1
134  #define syntax() syntax_err()
135  #define xstrdup strdup
136  #define error_msg printf
137  #else
138  typedef enum {
139  	REDIRECT_INPUT     = 1,
140  	REDIRECT_OVERWRITE = 2,
141  	REDIRECT_APPEND    = 3,
142  	REDIRECT_HEREIS    = 4,
143  	REDIRECT_IO        = 5
144  } redir_type;
145  
146  /* The descrip member of this structure is only used to make debugging
147   * output pretty */
148  struct {int mode; int default_fd; char *descrip;} redir_table[] = {
149  	{ 0,                         0, "()" },
150  	{ O_RDONLY,                  0, "<"  },
151  	{ O_CREAT|O_TRUNC|O_WRONLY,  1, ">"  },
152  	{ O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
153  	{ O_RDONLY,                 -1, "<<" },
154  	{ O_RDWR,                    1, "<>" }
155  };
156  #endif
157  
158  typedef enum {
159  	PIPE_SEQ = 1,
160  	PIPE_AND = 2,
161  	PIPE_OR  = 3,
162  	PIPE_BG  = 4,
163  } pipe_style;
164  
165  /* might eventually control execution */
166  typedef enum {
167  	RES_NONE  = 0,
168  	RES_IF    = 1,
169  	RES_THEN  = 2,
170  	RES_ELIF  = 3,
171  	RES_ELSE  = 4,
172  	RES_FI    = 5,
173  	RES_FOR   = 6,
174  	RES_WHILE = 7,
175  	RES_UNTIL = 8,
176  	RES_DO    = 9,
177  	RES_DONE  = 10,
178  	RES_XXXX  = 11,
179  	RES_IN    = 12,
180  	RES_SNTX  = 13
181  } reserved_style;
182  #define FLAG_END   (1<<RES_NONE)
183  #define FLAG_IF    (1<<RES_IF)
184  #define FLAG_THEN  (1<<RES_THEN)
185  #define FLAG_ELIF  (1<<RES_ELIF)
186  #define FLAG_ELSE  (1<<RES_ELSE)
187  #define FLAG_FI    (1<<RES_FI)
188  #define FLAG_FOR   (1<<RES_FOR)
189  #define FLAG_WHILE (1<<RES_WHILE)
190  #define FLAG_UNTIL (1<<RES_UNTIL)
191  #define FLAG_DO    (1<<RES_DO)
192  #define FLAG_DONE  (1<<RES_DONE)
193  #define FLAG_IN    (1<<RES_IN)
194  #define FLAG_START (1<<RES_XXXX)
195  
196  /* This holds pointers to the various results of parsing */
197  struct p_context {
198  	struct child_prog *child;
199  	struct pipe *list_head;
200  	struct pipe *pipe;
201  #ifndef __U_BOOT__
202  	struct redir_struct *pending_redirect;
203  #endif
204  	reserved_style w;
205  	int old_flag;				/* for figuring out valid reserved words */
206  	struct p_context *stack;
207  	int type;			/* define type of parser : ";$" common or special symbol */
208  	/* How about quoting status? */
209  };
210  
211  #ifndef __U_BOOT__
212  struct redir_struct {
213  	redir_type type;			/* type of redirection */
214  	int fd;						/* file descriptor being redirected */
215  	int dup;					/* -1, or file descriptor being duplicated */
216  	struct redir_struct *next;	/* pointer to the next redirect in the list */
217  	glob_t word;				/* *word.gl_pathv is the filename */
218  };
219  #endif
220  
221  struct child_prog {
222  #ifndef __U_BOOT__
223  	pid_t pid;					/* 0 if exited */
224  #endif
225  	char **argv;				/* program name and arguments */
226  	/* was quoted when parsed; copy of struct o_string.nonnull field */
227  	int *argv_nonnull;
228  #ifdef __U_BOOT__
229  	int    argc;                            /* number of program arguments */
230  #endif
231  	struct pipe *group;			/* if non-NULL, first in group or subshell */
232  #ifndef __U_BOOT__
233  	int subshell;				/* flag, non-zero if group must be forked */
234  	struct redir_struct *redirects;	/* I/O redirections */
235  	glob_t glob_result;			/* result of parameter globbing */
236  	int is_stopped;				/* is the program currently running? */
237  	struct pipe *family;		/* pointer back to the child's parent pipe */
238  #endif
239  	int sp;				/* number of SPECIAL_VAR_SYMBOL */
240  	int type;
241  };
242  
243  struct pipe {
244  #ifndef __U_BOOT__
245  	int jobid;					/* job number */
246  #endif
247  	int num_progs;				/* total number of programs in job */
248  #ifndef __U_BOOT__
249  	int running_progs;			/* number of programs running */
250  	char *text;					/* name of job */
251  	char *cmdbuf;				/* buffer various argv's point into */
252  	pid_t pgrp;					/* process group ID for the job */
253  #endif
254  	struct child_prog *progs;	/* array of commands in pipe */
255  	struct pipe *next;			/* to track background commands */
256  #ifndef __U_BOOT__
257  	int stopped_progs;			/* number of programs alive, but stopped */
258  	int job_context;			/* bitmask defining current context */
259  #endif
260  	pipe_style followup;		/* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
261  	reserved_style r_mode;		/* supports if, for, while, until */
262  };
263  
264  #ifndef __U_BOOT__
265  struct close_me {
266  	int fd;
267  	struct close_me *next;
268  };
269  #endif
270  
271  struct variables {
272  	char *name;
273  	char *value;
274  	int flg_export;
275  	int flg_read_only;
276  	struct variables *next;
277  };
278  
279  /* globals, connect us to the outside world
280   * the first three support $?, $#, and $1 */
281  #ifndef __U_BOOT__
282  char **global_argv;
283  unsigned int global_argc;
284  #endif
285  static unsigned int last_return_code;
286  #ifndef __U_BOOT__
287  extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
288  #endif
289  
290  /* "globals" within this file */
291  static uchar *ifs;
292  static char map[256];
293  #ifndef __U_BOOT__
294  static int fake_mode;
295  static int interactive;
296  static struct close_me *close_me_head;
297  static const char *cwd;
298  static struct pipe *job_list;
299  static unsigned int last_bg_pid;
300  static unsigned int last_jobid;
301  static unsigned int shell_terminal;
302  static char *PS1;
303  static char *PS2;
304  struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
305  struct variables *top_vars = &shell_ver;
306  #else
307  static int flag_repeat = 0;
308  static int do_repeat = 0;
309  static struct variables *top_vars = NULL ;
310  #endif /*__U_BOOT__ */
311  
312  #define B_CHUNK (100)
313  #define B_NOSPAC 1
314  
315  typedef struct {
316  	char *data;
317  	int length;
318  	int maxlen;
319  	int quote;
320  	int nonnull;
321  } o_string;
322  #define NULL_O_STRING {NULL,0,0,0,0}
323  /* used for initialization:
324  	o_string foo = NULL_O_STRING; */
325  
326  /* I can almost use ordinary FILE *.  Is open_memstream() universally
327   * available?  Where is it documented? */
328  struct in_str {
329  	const char *p;
330  #ifndef __U_BOOT__
331  	char peek_buf[2];
332  #endif
333  	int __promptme;
334  	int promptmode;
335  #ifndef __U_BOOT__
336  	FILE *file;
337  #endif
338  	int (*get) (struct in_str *);
339  	int (*peek) (struct in_str *);
340  };
341  #define b_getch(input) ((input)->get(input))
342  #define b_peek(input) ((input)->peek(input))
343  
344  #ifndef __U_BOOT__
345  #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
346  
347  struct built_in_command {
348  	char *cmd;					/* name */
349  	char *descr;				/* description */
350  	int (*function) (struct child_prog *);	/* function ptr */
351  };
352  #endif
353  
354  /* define DEBUG_SHELL for debugging output (obviously ;-)) */
355  #if 0
356  #define DEBUG_SHELL
357  #endif
358  
359  /* This should be in utility.c */
360  #ifdef DEBUG_SHELL
361  #ifndef __U_BOOT__
debug_printf(const char * format,...)362  static void debug_printf(const char *format, ...)
363  {
364  	va_list args;
365  	va_start(args, format);
366  	vfprintf(stderr, format, args);
367  	va_end(args);
368  }
369  #else
370  #define debug_printf(fmt,args...)	printf (fmt ,##args)
371  #endif
372  #else
debug_printf(const char * format,...)373  static inline void debug_printf(const char *format, ...) { }
374  #endif
375  #define final_printf debug_printf
376  
377  #ifdef __U_BOOT__
syntax_err(void)378  static void syntax_err(void) {
379  	 printf("syntax error\n");
380  }
381  #else
__syntax(char * file,int line)382  static void __syntax(char *file, int line) {
383  	error_msg("syntax error %s:%d", file, line);
384  }
385  #define syntax() __syntax(__FILE__, __LINE__)
386  #endif
387  
388  #ifdef __U_BOOT__
389  static void *xmalloc(size_t size);
390  static void *xrealloc(void *ptr, size_t size);
391  #else
392  /* Index of subroutines: */
393  /*   function prototypes for builtins */
394  static int builtin_cd(struct child_prog *child);
395  static int builtin_env(struct child_prog *child);
396  static int builtin_eval(struct child_prog *child);
397  static int builtin_exec(struct child_prog *child);
398  static int builtin_exit(struct child_prog *child);
399  static int builtin_export(struct child_prog *child);
400  static int builtin_fg_bg(struct child_prog *child);
401  static int builtin_help(struct child_prog *child);
402  static int builtin_jobs(struct child_prog *child);
403  static int builtin_pwd(struct child_prog *child);
404  static int builtin_read(struct child_prog *child);
405  static int builtin_set(struct child_prog *child);
406  static int builtin_shift(struct child_prog *child);
407  static int builtin_source(struct child_prog *child);
408  static int builtin_umask(struct child_prog *child);
409  static int builtin_unset(struct child_prog *child);
410  static int builtin_not_written(struct child_prog *child);
411  #endif
412  /*   o_string manipulation: */
413  static int b_check_space(o_string *o, int len);
414  static int b_addchr(o_string *o, int ch);
415  static void b_reset(o_string *o);
416  static int b_addqchr(o_string *o, int ch, int quote);
417  #ifndef __U_BOOT__
418  static int b_adduint(o_string *o, unsigned int i);
419  #endif
420  /*  in_str manipulations: */
421  static int static_get(struct in_str *i);
422  static int static_peek(struct in_str *i);
423  static int file_get(struct in_str *i);
424  static int file_peek(struct in_str *i);
425  #ifndef __U_BOOT__
426  static void setup_file_in_str(struct in_str *i, FILE *f);
427  #else
428  static void setup_file_in_str(struct in_str *i);
429  #endif
430  static void setup_string_in_str(struct in_str *i, const char *s);
431  #ifndef __U_BOOT__
432  /*  close_me manipulations: */
433  static void mark_open(int fd);
434  static void mark_closed(int fd);
435  static void close_all(void);
436  #endif
437  /*  "run" the final data structures: */
438  static char *indenter(int i);
439  static int free_pipe_list(struct pipe *head, int indent);
440  static int free_pipe(struct pipe *pi, int indent);
441  /*  really run the final data structures: */
442  #ifndef __U_BOOT__
443  static int setup_redirects(struct child_prog *prog, int squirrel[]);
444  #endif
445  static int run_list_real(struct pipe *pi);
446  #ifndef __U_BOOT__
447  static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
448  #endif
449  static int run_pipe_real(struct pipe *pi);
450  /*   extended glob support: */
451  #ifndef __U_BOOT__
452  static int globhack(const char *src, int flags, glob_t *pglob);
453  static int glob_needed(const char *s);
454  static int xglob(o_string *dest, int flags, glob_t *pglob);
455  #endif
456  /*   variable assignment: */
457  static int is_assignment(const char *s);
458  /*   data structure manipulation: */
459  #ifndef __U_BOOT__
460  static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
461  #endif
462  static void initialize_context(struct p_context *ctx);
463  static int done_word(o_string *dest, struct p_context *ctx);
464  static int done_command(struct p_context *ctx);
465  static int done_pipe(struct p_context *ctx, pipe_style type);
466  /*   primary string parsing: */
467  #ifndef __U_BOOT__
468  static int redirect_dup_num(struct in_str *input);
469  static int redirect_opt_num(o_string *o);
470  static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
471  static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
472  #endif
473  static char *lookup_param(char *src);
474  static char *make_string(char **inp, int *nonnull);
475  static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
476  #ifndef __U_BOOT__
477  static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
478  #endif
479  static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
480  /*   setup: */
481  static int parse_stream_outer(struct in_str *inp, int flag);
482  #ifndef __U_BOOT__
483  static int parse_string_outer(const char *s, int flag);
484  static int parse_file_outer(FILE *f);
485  #endif
486  #ifndef __U_BOOT__
487  /*   job management: */
488  static int checkjobs(struct pipe* fg_pipe);
489  static void insert_bg_job(struct pipe *pi);
490  static void remove_bg_job(struct pipe *pi);
491  #endif
492  /*     local variable support */
493  static char **make_list_in(char **inp, char *name);
494  static char *insert_var_value(char *inp);
495  static char *insert_var_value_sub(char *inp, int tag_subst);
496  
497  #ifndef __U_BOOT__
498  /* Table of built-in functions.  They can be forked or not, depending on
499   * context: within pipes, they fork.  As simple commands, they do not.
500   * When used in non-forking context, they can change global variables
501   * in the parent shell process.  If forked, of course they can not.
502   * For example, 'unset foo | whatever' will parse and run, but foo will
503   * still be set at the end. */
504  static struct built_in_command bltins[] = {
505  	{"bg", "Resume a job in the background", builtin_fg_bg},
506  	{"break", "Exit for, while or until loop", builtin_not_written},
507  	{"cd", "Change working directory", builtin_cd},
508  	{"continue", "Continue for, while or until loop", builtin_not_written},
509  	{"env", "Print all environment variables", builtin_env},
510  	{"eval", "Construct and run shell command", builtin_eval},
511  	{"exec", "Exec command, replacing this shell with the exec'd process",
512  		builtin_exec},
513  	{"exit", "Exit from shell()", builtin_exit},
514  	{"export", "Set environment variable", builtin_export},
515  	{"fg", "Bring job into the foreground", builtin_fg_bg},
516  	{"jobs", "Lists the active jobs", builtin_jobs},
517  	{"pwd", "Print current directory", builtin_pwd},
518  	{"read", "Input environment variable", builtin_read},
519  	{"return", "Return from a function", builtin_not_written},
520  	{"set", "Set/unset shell local variables", builtin_set},
521  	{"shift", "Shift positional parameters", builtin_shift},
522  	{"trap", "Trap signals", builtin_not_written},
523  	{"ulimit","Controls resource limits", builtin_not_written},
524  	{"umask","Sets file creation mask", builtin_umask},
525  	{"unset", "Unset environment variable", builtin_unset},
526  	{".", "Source-in and run commands in a file", builtin_source},
527  	{"help", "List shell built-in commands", builtin_help},
528  	{NULL, NULL, NULL}
529  };
530  
set_cwd(void)531  static const char *set_cwd(void)
532  {
533  	if(cwd==unknown)
534  		cwd = NULL;     /* xgetcwd(arg) called free(arg) */
535  	cwd = xgetcwd((char *)cwd);
536  	if (!cwd)
537  		cwd = unknown;
538  	return cwd;
539  }
540  
541  /* built-in 'eval' handler */
builtin_eval(struct child_prog * child)542  static int builtin_eval(struct child_prog *child)
543  {
544  	char *str = NULL;
545  	int rcode = EXIT_SUCCESS;
546  
547  	if (child->argv[1]) {
548  		str = make_string(child->argv + 1);
549  		parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
550  					FLAG_PARSE_SEMICOLON);
551  		free(str);
552  		rcode = last_return_code;
553  	}
554  	return rcode;
555  }
556  
557  /* built-in 'cd <path>' handler */
builtin_cd(struct child_prog * child)558  static int builtin_cd(struct child_prog *child)
559  {
560  	char *newdir;
561  	if (child->argv[1] == NULL)
562  		newdir = env_get("HOME");
563  	else
564  		newdir = child->argv[1];
565  	if (chdir(newdir)) {
566  		printf("cd: %s: %s\n", newdir, strerror(errno));
567  		return EXIT_FAILURE;
568  	}
569  	set_cwd();
570  	return EXIT_SUCCESS;
571  }
572  
573  /* built-in 'env' handler */
builtin_env(struct child_prog * dummy)574  static int builtin_env(struct child_prog *dummy)
575  {
576  	char **e = environ;
577  	if (e == NULL) return EXIT_FAILURE;
578  	for (; *e; e++) {
579  		puts(*e);
580  	}
581  	return EXIT_SUCCESS;
582  }
583  
584  /* built-in 'exec' handler */
builtin_exec(struct child_prog * child)585  static int builtin_exec(struct child_prog *child)
586  {
587  	if (child->argv[1] == NULL)
588  		return EXIT_SUCCESS;   /* Really? */
589  	child->argv++;
590  	pseudo_exec(child);
591  	/* never returns */
592  }
593  
594  /* built-in 'exit' handler */
builtin_exit(struct child_prog * child)595  static int builtin_exit(struct child_prog *child)
596  {
597  	if (child->argv[1] == NULL)
598  		exit(last_return_code);
599  	exit (atoi(child->argv[1]));
600  }
601  
602  /* built-in 'export VAR=value' handler */
builtin_export(struct child_prog * child)603  static int builtin_export(struct child_prog *child)
604  {
605  	int res = 0;
606  	char *name = child->argv[1];
607  
608  	if (name == NULL) {
609  		return (builtin_env(child));
610  	}
611  
612  	name = strdup(name);
613  
614  	if(name) {
615  		char *value = strchr(name, '=');
616  
617  		if (!value) {
618  			char *tmp;
619  			/* They are exporting something without an =VALUE */
620  
621  			value = get_local_var(name);
622  			if (value) {
623  				size_t ln = strlen(name);
624  
625  				tmp = realloc(name, ln+strlen(value)+2);
626  				if(tmp==NULL)
627  					res = -1;
628  				else {
629  					sprintf(tmp+ln, "=%s", value);
630  					name = tmp;
631  				}
632  			} else {
633  				/* bash does not return an error when trying to export
634  				 * an undefined variable.  Do likewise. */
635  				res = 1;
636  			}
637  		}
638  	}
639  	if (res<0)
640  		perror_msg("export");
641  	else if(res==0)
642  		res = set_local_var(name, 1);
643  	else
644  		res = 0;
645  	free(name);
646  	return res;
647  }
648  
649  /* built-in 'fg' and 'bg' handler */
builtin_fg_bg(struct child_prog * child)650  static int builtin_fg_bg(struct child_prog *child)
651  {
652  	int i, jobnum;
653  	struct pipe *pi=NULL;
654  
655  	if (!interactive)
656  		return EXIT_FAILURE;
657  	/* If they gave us no args, assume they want the last backgrounded task */
658  	if (!child->argv[1]) {
659  		for (pi = job_list; pi; pi = pi->next) {
660  			if (pi->jobid == last_jobid) {
661  				break;
662  			}
663  		}
664  		if (!pi) {
665  			error_msg("%s: no current job", child->argv[0]);
666  			return EXIT_FAILURE;
667  		}
668  	} else {
669  		if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
670  			error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
671  			return EXIT_FAILURE;
672  		}
673  		for (pi = job_list; pi; pi = pi->next) {
674  			if (pi->jobid == jobnum) {
675  				break;
676  			}
677  		}
678  		if (!pi) {
679  			error_msg("%s: %d: no such job", child->argv[0], jobnum);
680  			return EXIT_FAILURE;
681  		}
682  	}
683  
684  	if (*child->argv[0] == 'f') {
685  		/* Put the job into the foreground.  */
686  		tcsetpgrp(shell_terminal, pi->pgrp);
687  	}
688  
689  	/* Restart the processes in the job */
690  	for (i = 0; i < pi->num_progs; i++)
691  		pi->progs[i].is_stopped = 0;
692  
693  	if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) {
694  		if (i == ESRCH) {
695  			remove_bg_job(pi);
696  		} else {
697  			perror_msg("kill (SIGCONT)");
698  		}
699  	}
700  
701  	pi->stopped_progs = 0;
702  	return EXIT_SUCCESS;
703  }
704  
705  /* built-in 'help' handler */
builtin_help(struct child_prog * dummy)706  static int builtin_help(struct child_prog *dummy)
707  {
708  	struct built_in_command *x;
709  
710  	printf("\nBuilt-in commands:\n");
711  	printf("-------------------\n");
712  	for (x = bltins; x->cmd; x++) {
713  		if (x->descr==NULL)
714  			continue;
715  		printf("%s\t%s\n", x->cmd, x->descr);
716  	}
717  	printf("\n\n");
718  	return EXIT_SUCCESS;
719  }
720  
721  /* built-in 'jobs' handler */
builtin_jobs(struct child_prog * child)722  static int builtin_jobs(struct child_prog *child)
723  {
724  	struct pipe *job;
725  	char *status_string;
726  
727  	for (job = job_list; job; job = job->next) {
728  		if (job->running_progs == job->stopped_progs)
729  			status_string = "Stopped";
730  		else
731  			status_string = "Running";
732  
733  		printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
734  	}
735  	return EXIT_SUCCESS;
736  }
737  
738  
739  /* built-in 'pwd' handler */
builtin_pwd(struct child_prog * dummy)740  static int builtin_pwd(struct child_prog *dummy)
741  {
742  	puts(set_cwd());
743  	return EXIT_SUCCESS;
744  }
745  
746  /* built-in 'read VAR' handler */
builtin_read(struct child_prog * child)747  static int builtin_read(struct child_prog *child)
748  {
749  	int res;
750  
751  	if (child->argv[1]) {
752  		char string[BUFSIZ];
753  		char *var = 0;
754  
755  		string[0] = 0;  /* In case stdin has only EOF */
756  		/* read string */
757  		fgets(string, sizeof(string), stdin);
758  		chomp(string);
759  		var = malloc(strlen(child->argv[1])+strlen(string)+2);
760  		if(var) {
761  			sprintf(var, "%s=%s", child->argv[1], string);
762  			res = set_local_var(var, 0);
763  		} else
764  			res = -1;
765  		if (res)
766  			fprintf(stderr, "read: %m\n");
767  		free(var);      /* So not move up to avoid breaking errno */
768  		return res;
769  	} else {
770  		do res=getchar(); while(res!='\n' && res!=EOF);
771  		return 0;
772  	}
773  }
774  
775  /* built-in 'set VAR=value' handler */
builtin_set(struct child_prog * child)776  static int builtin_set(struct child_prog *child)
777  {
778  	char *temp = child->argv[1];
779  	struct variables *e;
780  
781  	if (temp == NULL)
782  		for(e = top_vars; e; e=e->next)
783  			printf("%s=%s\n", e->name, e->value);
784  	else
785  		set_local_var(temp, 0);
786  
787  		return EXIT_SUCCESS;
788  }
789  
790  
791  /* Built-in 'shift' handler */
builtin_shift(struct child_prog * child)792  static int builtin_shift(struct child_prog *child)
793  {
794  	int n=1;
795  	if (child->argv[1]) {
796  		n=atoi(child->argv[1]);
797  	}
798  	if (n>=0 && n<global_argc) {
799  		/* XXX This probably breaks $0 */
800  		global_argc -= n;
801  		global_argv += n;
802  		return EXIT_SUCCESS;
803  	} else {
804  		return EXIT_FAILURE;
805  	}
806  }
807  
808  /* Built-in '.' handler (read-in and execute commands from file) */
builtin_source(struct child_prog * child)809  static int builtin_source(struct child_prog *child)
810  {
811  	FILE *input;
812  	int status;
813  
814  	if (child->argv[1] == NULL)
815  		return EXIT_FAILURE;
816  
817  	/* XXX search through $PATH is missing */
818  	input = fopen(child->argv[1], "r");
819  	if (!input) {
820  		error_msg("Couldn't open file '%s'", child->argv[1]);
821  		return EXIT_FAILURE;
822  	}
823  
824  	/* Now run the file */
825  	/* XXX argv and argc are broken; need to save old global_argv
826  	 * (pointer only is OK!) on this stack frame,
827  	 * set global_argv=child->argv+1, recurse, and restore. */
828  	mark_open(fileno(input));
829  	status = parse_file_outer(input);
830  	mark_closed(fileno(input));
831  	fclose(input);
832  	return (status);
833  }
834  
builtin_umask(struct child_prog * child)835  static int builtin_umask(struct child_prog *child)
836  {
837  	mode_t new_umask;
838  	const char *arg = child->argv[1];
839  	char *end;
840  	if (arg) {
841  		new_umask=strtoul(arg, &end, 8);
842  		if (*end!='\0' || end == arg) {
843  			return EXIT_FAILURE;
844  		}
845  	} else {
846  		printf("%.3o\n", (unsigned int) (new_umask=umask(0)));
847  	}
848  	umask(new_umask);
849  	return EXIT_SUCCESS;
850  }
851  
852  /* built-in 'unset VAR' handler */
builtin_unset(struct child_prog * child)853  static int builtin_unset(struct child_prog *child)
854  {
855  	/* bash returned already true */
856  	unset_local_var(child->argv[1]);
857  	return EXIT_SUCCESS;
858  }
859  
builtin_not_written(struct child_prog * child)860  static int builtin_not_written(struct child_prog *child)
861  {
862  	printf("builtin_%s not written\n",child->argv[0]);
863  	return EXIT_FAILURE;
864  }
865  #endif
866  
b_check_space(o_string * o,int len)867  static int b_check_space(o_string *o, int len)
868  {
869  	/* It would be easy to drop a more restrictive policy
870  	 * in here, such as setting a maximum string length */
871  	if (o->length + len > o->maxlen) {
872  		char *old_data = o->data;
873  		/* assert (data == NULL || o->maxlen != 0); */
874  		o->maxlen += max(2*len, B_CHUNK);
875  		o->data = realloc(o->data, 1 + o->maxlen);
876  		if (o->data == NULL) {
877  			free(old_data);
878  		}
879  	}
880  	return o->data == NULL;
881  }
882  
b_addchr(o_string * o,int ch)883  static int b_addchr(o_string *o, int ch)
884  {
885  	debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
886  	if (b_check_space(o, 1)) return B_NOSPAC;
887  	o->data[o->length] = ch;
888  	o->length++;
889  	o->data[o->length] = '\0';
890  	return 0;
891  }
892  
b_reset(o_string * o)893  static void b_reset(o_string *o)
894  {
895  	o->length = 0;
896  	o->nonnull = 0;
897  	if (o->data != NULL) *o->data = '\0';
898  }
899  
b_free(o_string * o)900  static void b_free(o_string *o)
901  {
902  	b_reset(o);
903  	free(o->data);
904  	o->data = NULL;
905  	o->maxlen = 0;
906  }
907  
908  /* My analysis of quoting semantics tells me that state information
909   * is associated with a destination, not a source.
910   */
b_addqchr(o_string * o,int ch,int quote)911  static int b_addqchr(o_string *o, int ch, int quote)
912  {
913  	if (quote && strchr("*?[\\",ch)) {
914  		int rc;
915  		rc = b_addchr(o, '\\');
916  		if (rc) return rc;
917  	}
918  	return b_addchr(o, ch);
919  }
920  
921  #ifndef __U_BOOT__
b_adduint(o_string * o,unsigned int i)922  static int b_adduint(o_string *o, unsigned int i)
923  {
924  	int r;
925  	char *p = simple_itoa(i);
926  	/* no escape checking necessary */
927  	do r=b_addchr(o, *p++); while (r==0 && *p);
928  	return r;
929  }
930  #endif
931  
static_get(struct in_str * i)932  static int static_get(struct in_str *i)
933  {
934  	int ch = *i->p++;
935  	if (ch=='\0') return EOF;
936  	return ch;
937  }
938  
static_peek(struct in_str * i)939  static int static_peek(struct in_str *i)
940  {
941  	return *i->p;
942  }
943  
944  #ifndef __U_BOOT__
cmdedit_set_initial_prompt(void)945  static inline void cmdedit_set_initial_prompt(void)
946  {
947  #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
948  	PS1 = NULL;
949  #else
950  	PS1 = env_get("PS1");
951  	if(PS1==0)
952  		PS1 = "\\w \\$ ";
953  #endif
954  }
955  
setup_prompt_string(int promptmode,char ** prompt_str)956  static inline void setup_prompt_string(int promptmode, char **prompt_str)
957  {
958  	debug_printf("setup_prompt_string %d ",promptmode);
959  #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
960  	/* Set up the prompt */
961  	if (promptmode == 1) {
962  		free(PS1);
963  		PS1=xmalloc(strlen(cwd)+4);
964  		sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ?  "$ ":"# ");
965  		*prompt_str = PS1;
966  	} else {
967  		*prompt_str = PS2;
968  	}
969  #else
970  	*prompt_str = (promptmode==1)? PS1 : PS2;
971  #endif
972  	debug_printf("result %s\n",*prompt_str);
973  }
974  #endif
975  
976  #ifdef __U_BOOT__
uboot_cli_readline(struct in_str * i)977  static int uboot_cli_readline(struct in_str *i)
978  {
979  	char *prompt;
980  	char __maybe_unused *ps_prompt = NULL;
981  
982  	if (i->promptmode == 1)
983  		prompt = CONFIG_SYS_PROMPT;
984  	else
985  		prompt = CONFIG_SYS_PROMPT_HUSH_PS2;
986  
987  #ifdef CONFIG_CMDLINE_PS_SUPPORT
988  	if (i->promptmode == 1)
989  		ps_prompt = env_get("PS1");
990  	else
991  		ps_prompt = env_get("PS2");
992  	if (ps_prompt)
993  		prompt = ps_prompt;
994  #endif
995  
996  	return cli_readline(prompt);
997  }
998  #endif
999  
get_user_input(struct in_str * i)1000  static void get_user_input(struct in_str *i)
1001  {
1002  #ifndef __U_BOOT__
1003  	char *prompt_str;
1004  	static char the_command[BUFSIZ];
1005  
1006  	setup_prompt_string(i->promptmode, &prompt_str);
1007  #ifdef CONFIG_FEATURE_COMMAND_EDITING
1008  	/*
1009  	 ** enable command line editing only while a command line
1010  	 ** is actually being read; otherwise, we'll end up bequeathing
1011  	 ** atexit() handlers and other unwanted stuff to our
1012  	 ** child processes (rob@sysgo.de)
1013  	 */
1014  	cmdedit_read_input(prompt_str, the_command);
1015  #else
1016  	fputs(prompt_str, stdout);
1017  	fflush(stdout);
1018  	the_command[0]=fgetc(i->file);
1019  	the_command[1]='\0';
1020  #endif
1021  	fflush(stdout);
1022  	i->p = the_command;
1023  #else
1024  	int n;
1025  	static char the_command[CONFIG_SYS_CBSIZE + 1];
1026  
1027  	bootretry_reset_cmd_timeout();
1028  	i->__promptme = 1;
1029  	n = uboot_cli_readline(i);
1030  
1031  #ifdef CONFIG_BOOT_RETRY_TIME
1032  	if (n == -2) {
1033  	  puts("\nTimeout waiting for command\n");
1034  #  ifdef CONFIG_RESET_TO_RETRY
1035  	  do_reset(NULL, 0, 0, NULL);
1036  #  else
1037  #	error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1038  #  endif
1039  	}
1040  #endif
1041  	if (n == -1 ) {
1042  		flag_repeat = 0;
1043  		i->__promptme = 0;
1044  	}
1045  	n = strlen(console_buffer);
1046  	console_buffer[n] = '\n';
1047  	console_buffer[n+1]= '\0';
1048  	if (had_ctrlc()) flag_repeat = 0;
1049  	clear_ctrlc();
1050  	do_repeat = 0;
1051  	if (i->promptmode == 1) {
1052  		if (console_buffer[0] == '\n'&& flag_repeat == 0) {
1053  			strcpy(the_command,console_buffer);
1054  		}
1055  		else {
1056  			if (console_buffer[0] != '\n') {
1057  				strcpy(the_command,console_buffer);
1058  				flag_repeat = 1;
1059  			}
1060  			else {
1061  				do_repeat = 1;
1062  			}
1063  		}
1064  		i->p = the_command;
1065  	}
1066  	else {
1067  		if (console_buffer[0] != '\n') {
1068  			if (strlen(the_command) + strlen(console_buffer)
1069  			    < CONFIG_SYS_CBSIZE) {
1070  				n = strlen(the_command);
1071  				the_command[n-1] = ' ';
1072  				strcpy(&the_command[n],console_buffer);
1073  			}
1074  			else {
1075  				the_command[0] = '\n';
1076  				the_command[1] = '\0';
1077  				flag_repeat = 0;
1078  			}
1079  		}
1080  		if (i->__promptme == 0) {
1081  			the_command[0] = '\n';
1082  			the_command[1] = '\0';
1083  		}
1084  		i->p = console_buffer;
1085  	}
1086  #endif
1087  }
1088  
1089  /* This is the magic location that prints prompts
1090   * and gets data back from the user */
file_get(struct in_str * i)1091  static int file_get(struct in_str *i)
1092  {
1093  	int ch;
1094  
1095  	ch = 0;
1096  	/* If there is data waiting, eat it up */
1097  	if (i->p && *i->p) {
1098  		ch = *i->p++;
1099  	} else {
1100  		/* need to double check i->file because we might be doing something
1101  		 * more complicated by now, like sourcing or substituting. */
1102  #ifndef __U_BOOT__
1103  		if (i->__promptme && interactive && i->file == stdin) {
1104  			while(! i->p || (interactive && strlen(i->p)==0) ) {
1105  #else
1106  			while(! i->p  || strlen(i->p)==0 ) {
1107  #endif
1108  				get_user_input(i);
1109  			}
1110  			i->promptmode=2;
1111  #ifndef __U_BOOT__
1112  			i->__promptme = 0;
1113  #endif
1114  			if (i->p && *i->p) {
1115  				ch = *i->p++;
1116  			}
1117  #ifndef __U_BOOT__
1118  		} else {
1119  			ch = fgetc(i->file);
1120  		}
1121  
1122  #endif
1123  		debug_printf("b_getch: got a %d\n", ch);
1124  	}
1125  #ifndef __U_BOOT__
1126  	if (ch == '\n') i->__promptme=1;
1127  #endif
1128  	return ch;
1129  }
1130  
1131  /* All the callers guarantee this routine will never be
1132   * used right after a newline, so prompting is not needed.
1133   */
1134  static int file_peek(struct in_str *i)
1135  {
1136  #ifndef __U_BOOT__
1137  	if (i->p && *i->p) {
1138  #endif
1139  		return *i->p;
1140  #ifndef __U_BOOT__
1141  	} else {
1142  		i->peek_buf[0] = fgetc(i->file);
1143  		i->peek_buf[1] = '\0';
1144  		i->p = i->peek_buf;
1145  		debug_printf("b_peek: got a %d\n", *i->p);
1146  		return *i->p;
1147  	}
1148  #endif
1149  }
1150  
1151  #ifndef __U_BOOT__
1152  static void setup_file_in_str(struct in_str *i, FILE *f)
1153  #else
1154  static void setup_file_in_str(struct in_str *i)
1155  #endif
1156  {
1157  	i->peek = file_peek;
1158  	i->get = file_get;
1159  	i->__promptme=1;
1160  	i->promptmode=1;
1161  #ifndef __U_BOOT__
1162  	i->file = f;
1163  #endif
1164  	i->p = NULL;
1165  }
1166  
1167  static void setup_string_in_str(struct in_str *i, const char *s)
1168  {
1169  	i->peek = static_peek;
1170  	i->get = static_get;
1171  	i->__promptme=1;
1172  	i->promptmode=1;
1173  	i->p = s;
1174  }
1175  
1176  #ifndef __U_BOOT__
1177  static void mark_open(int fd)
1178  {
1179  	struct close_me *new = xmalloc(sizeof(struct close_me));
1180  	new->fd = fd;
1181  	new->next = close_me_head;
1182  	close_me_head = new;
1183  }
1184  
1185  static void mark_closed(int fd)
1186  {
1187  	struct close_me *tmp;
1188  	if (close_me_head == NULL || close_me_head->fd != fd)
1189  		error_msg_and_die("corrupt close_me");
1190  	tmp = close_me_head;
1191  	close_me_head = close_me_head->next;
1192  	free(tmp);
1193  }
1194  
1195  static void close_all(void)
1196  {
1197  	struct close_me *c;
1198  	for (c=close_me_head; c; c=c->next) {
1199  		close(c->fd);
1200  	}
1201  	close_me_head = NULL;
1202  }
1203  
1204  /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1205   * and stderr if they are redirected. */
1206  static int setup_redirects(struct child_prog *prog, int squirrel[])
1207  {
1208  	int openfd, mode;
1209  	struct redir_struct *redir;
1210  
1211  	for (redir=prog->redirects; redir; redir=redir->next) {
1212  		if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1213  			/* something went wrong in the parse.  Pretend it didn't happen */
1214  			continue;
1215  		}
1216  		if (redir->dup == -1) {
1217  			mode=redir_table[redir->type].mode;
1218  			openfd = open(redir->word.gl_pathv[0], mode, 0666);
1219  			if (openfd < 0) {
1220  			/* this could get lost if stderr has been redirected, but
1221  			   bash and ash both lose it as well (though zsh doesn't!) */
1222  				perror_msg("error opening %s", redir->word.gl_pathv[0]);
1223  				return 1;
1224  			}
1225  		} else {
1226  			openfd = redir->dup;
1227  		}
1228  
1229  		if (openfd != redir->fd) {
1230  			if (squirrel && redir->fd < 3) {
1231  				squirrel[redir->fd] = dup(redir->fd);
1232  			}
1233  			if (openfd == -3) {
1234  				close(openfd);
1235  			} else {
1236  				dup2(openfd, redir->fd);
1237  				if (redir->dup == -1)
1238  					close (openfd);
1239  			}
1240  		}
1241  	}
1242  	return 0;
1243  }
1244  
1245  static void restore_redirects(int squirrel[])
1246  {
1247  	int i, fd;
1248  	for (i=0; i<3; i++) {
1249  		fd = squirrel[i];
1250  		if (fd != -1) {
1251  			/* No error checking.  I sure wouldn't know what
1252  			 * to do with an error if I found one! */
1253  			dup2(fd, i);
1254  			close(fd);
1255  		}
1256  	}
1257  }
1258  
1259  /* never returns */
1260  /* XXX no exit() here.  If you don't exec, use _exit instead.
1261   * The at_exit handlers apparently confuse the calling process,
1262   * in particular stdin handling.  Not sure why? */
1263  static void pseudo_exec(struct child_prog *child)
1264  {
1265  	int i, rcode;
1266  	char *p;
1267  	struct built_in_command *x;
1268  	if (child->argv) {
1269  		for (i=0; is_assignment(child->argv[i]); i++) {
1270  			debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
1271  			p = insert_var_value(child->argv[i]);
1272  			putenv(strdup(p));
1273  			if (p != child->argv[i]) free(p);
1274  		}
1275  		child->argv+=i;  /* XXX this hack isn't so horrible, since we are about
1276  					to exit, and therefore don't need to keep data
1277  					structures consistent for free() use. */
1278  		/* If a variable is assigned in a forest, and nobody listens,
1279  		 * was it ever really set?
1280  		 */
1281  		if (child->argv[0] == NULL) {
1282  			_exit(EXIT_SUCCESS);
1283  		}
1284  
1285  		/*
1286  		 * Check if the command matches any of the builtins.
1287  		 * Depending on context, this might be redundant.  But it's
1288  		 * easier to waste a few CPU cycles than it is to figure out
1289  		 * if this is one of those cases.
1290  		 */
1291  		for (x = bltins; x->cmd; x++) {
1292  			if (strcmp(child->argv[0], x->cmd) == 0 ) {
1293  				debug_printf("builtin exec %s\n", child->argv[0]);
1294  				rcode = x->function(child);
1295  				fflush(stdout);
1296  				_exit(rcode);
1297  			}
1298  		}
1299  
1300  		/* Check if the command matches any busybox internal commands
1301  		 * ("applets") here.
1302  		 * FIXME: This feature is not 100% safe, since
1303  		 * BusyBox is not fully reentrant, so we have no guarantee the things
1304  		 * from the .bss are still zeroed, or that things from .data are still
1305  		 * at their defaults.  We could exec ourself from /proc/self/exe, but I
1306  		 * really dislike relying on /proc for things.  We could exec ourself
1307  		 * from global_argv[0], but if we are in a chroot, we may not be able
1308  		 * to find ourself... */
1309  #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1310  		{
1311  			int argc_l;
1312  			char** argv_l=child->argv;
1313  			char *name = child->argv[0];
1314  
1315  #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
1316  			/* Following discussions from November 2000 on the busybox mailing
1317  			 * list, the default configuration, (without
1318  			 * get_last_path_component()) lets the user force use of an
1319  			 * external command by specifying the full (with slashes) filename.
1320  			 * If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN then applets
1321  			 * _aways_ override external commands, so if you want to run
1322  			 * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the
1323  			 * filesystem and is _not_ busybox.  Some systems may want this,
1324  			 * most do not.  */
1325  			name = get_last_path_component(name);
1326  #endif
1327  			/* Count argc for use in a second... */
1328  			for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
1329  			optind = 1;
1330  			debug_printf("running applet %s\n", name);
1331  			run_applet_by_name(name, argc_l, child->argv);
1332  		}
1333  #endif
1334  		debug_printf("exec of %s\n",child->argv[0]);
1335  		execvp(child->argv[0],child->argv);
1336  		perror_msg("couldn't exec: %s",child->argv[0]);
1337  		_exit(1);
1338  	} else if (child->group) {
1339  		debug_printf("runtime nesting to group\n");
1340  		interactive=0;    /* crucial!!!! */
1341  		rcode = run_list_real(child->group);
1342  		/* OK to leak memory by not calling free_pipe_list,
1343  		 * since this process is about to exit */
1344  		_exit(rcode);
1345  	} else {
1346  		/* Can happen.  See what bash does with ">foo" by itself. */
1347  		debug_printf("trying to pseudo_exec null command\n");
1348  		_exit(EXIT_SUCCESS);
1349  	}
1350  }
1351  
1352  static void insert_bg_job(struct pipe *pi)
1353  {
1354  	struct pipe *thejob;
1355  
1356  	/* Linear search for the ID of the job to use */
1357  	pi->jobid = 1;
1358  	for (thejob = job_list; thejob; thejob = thejob->next)
1359  		if (thejob->jobid >= pi->jobid)
1360  			pi->jobid = thejob->jobid + 1;
1361  
1362  	/* add thejob to the list of running jobs */
1363  	if (!job_list) {
1364  		thejob = job_list = xmalloc(sizeof(*thejob));
1365  	} else {
1366  		for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
1367  		thejob->next = xmalloc(sizeof(*thejob));
1368  		thejob = thejob->next;
1369  	}
1370  
1371  	/* physically copy the struct job */
1372  	memcpy(thejob, pi, sizeof(struct pipe));
1373  	thejob->next = NULL;
1374  	thejob->running_progs = thejob->num_progs;
1375  	thejob->stopped_progs = 0;
1376  	thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1377  
1378  	/*if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) */
1379  	{
1380  		char *bar=thejob->text;
1381  		char **foo=pi->progs[0].argv;
1382  		while(foo && *foo) {
1383  			bar += sprintf(bar, "%s ", *foo++);
1384  		}
1385  	}
1386  
1387  	/* we don't wait for background thejobs to return -- append it
1388  	   to the list of backgrounded thejobs and leave it alone */
1389  	printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1390  	last_bg_pid = thejob->progs[0].pid;
1391  	last_jobid = thejob->jobid;
1392  }
1393  
1394  /* remove a backgrounded job */
1395  static void remove_bg_job(struct pipe *pi)
1396  {
1397  	struct pipe *prev_pipe;
1398  
1399  	if (pi == job_list) {
1400  		job_list = pi->next;
1401  	} else {
1402  		prev_pipe = job_list;
1403  		while (prev_pipe->next != pi)
1404  			prev_pipe = prev_pipe->next;
1405  		prev_pipe->next = pi->next;
1406  	}
1407  	if (job_list)
1408  		last_jobid = job_list->jobid;
1409  	else
1410  		last_jobid = 0;
1411  
1412  	pi->stopped_progs = 0;
1413  	free_pipe(pi, 0);
1414  	free(pi);
1415  }
1416  
1417  /* Checks to see if any processes have exited -- if they
1418     have, figure out why and see if a job has completed */
1419  static int checkjobs(struct pipe* fg_pipe)
1420  {
1421  	int attributes;
1422  	int status;
1423  	int prognum = 0;
1424  	struct pipe *pi;
1425  	pid_t childpid;
1426  
1427  	attributes = WUNTRACED;
1428  	if (fg_pipe==NULL) {
1429  		attributes |= WNOHANG;
1430  	}
1431  
1432  	while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1433  		if (fg_pipe) {
1434  			int i, rcode = 0;
1435  			for (i=0; i < fg_pipe->num_progs; i++) {
1436  				if (fg_pipe->progs[i].pid == childpid) {
1437  					if (i==fg_pipe->num_progs-1)
1438  						rcode=WEXITSTATUS(status);
1439  					(fg_pipe->num_progs)--;
1440  					return(rcode);
1441  				}
1442  			}
1443  		}
1444  
1445  		for (pi = job_list; pi; pi = pi->next) {
1446  			prognum = 0;
1447  			while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1448  				prognum++;
1449  			}
1450  			if (prognum < pi->num_progs)
1451  				break;
1452  		}
1453  
1454  		if(pi==NULL) {
1455  			debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
1456  			continue;
1457  		}
1458  
1459  		if (WIFEXITED(status) || WIFSIGNALED(status)) {
1460  			/* child exited */
1461  			pi->running_progs--;
1462  			pi->progs[prognum].pid = 0;
1463  
1464  			if (!pi->running_progs) {
1465  				printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
1466  				remove_bg_job(pi);
1467  			}
1468  		} else {
1469  			/* child stopped */
1470  			pi->stopped_progs++;
1471  			pi->progs[prognum].is_stopped = 1;
1472  
1473  #if 0
1474  			/* Printing this stuff is a pain, since it tends to
1475  			 * overwrite the prompt an inconveinient moments.  So
1476  			 * don't do that.  */
1477  			if (pi->stopped_progs == pi->num_progs) {
1478  				printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
1479  			}
1480  #endif
1481  		}
1482  	}
1483  
1484  	if (childpid == -1 && errno != ECHILD)
1485  		perror_msg("waitpid");
1486  
1487  	/* move the shell to the foreground */
1488  	/*if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) */
1489  	/*	perror_msg("tcsetpgrp-2"); */
1490  	return -1;
1491  }
1492  
1493  /* Figure out our controlling tty, checking in order stderr,
1494   * stdin, and stdout.  If check_pgrp is set, also check that
1495   * we belong to the foreground process group associated with
1496   * that tty.  The value of shell_terminal is needed in order to call
1497   * tcsetpgrp(shell_terminal, ...); */
1498  void controlling_tty(int check_pgrp)
1499  {
1500  	pid_t curpgrp;
1501  
1502  	if ((curpgrp = tcgetpgrp(shell_terminal = 2)) < 0
1503  			&& (curpgrp = tcgetpgrp(shell_terminal = 0)) < 0
1504  			&& (curpgrp = tcgetpgrp(shell_terminal = 1)) < 0)
1505  		goto shell_terminal_error;
1506  
1507  	if (check_pgrp && curpgrp != getpgid(0))
1508  		goto shell_terminal_error;
1509  
1510  	return;
1511  
1512  shell_terminal_error:
1513  		shell_terminal = -1;
1514  		return;
1515  }
1516  #endif
1517  
1518  /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1519   * to finish.  See checkjobs().
1520   *
1521   * return code is normally -1, when the caller has to wait for children
1522   * to finish to determine the exit status of the pipe.  If the pipe
1523   * is a simple builtin command, however, the action is done by the
1524   * time run_pipe_real returns, and the exit code is provided as the
1525   * return value.
1526   *
1527   * The input of the pipe is always stdin, the output is always
1528   * stdout.  The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1529   * because it tries to avoid running the command substitution in
1530   * subshell, when that is in fact necessary.  The subshell process
1531   * now has its stdout directed to the input of the appropriate pipe,
1532   * so this routine is noticeably simpler.
1533   */
1534  static int run_pipe_real(struct pipe *pi)
1535  {
1536  	int i;
1537  #ifndef __U_BOOT__
1538  	int nextin, nextout;
1539  	int pipefds[2];				/* pipefds[0] is for reading */
1540  	struct child_prog *child;
1541  	struct built_in_command *x;
1542  	char *p;
1543  # if __GNUC__
1544  	/* Avoid longjmp clobbering */
1545  	(void) &i;
1546  	(void) &nextin;
1547  	(void) &nextout;
1548  	(void) &child;
1549  # endif
1550  #else
1551  	int nextin;
1552  	int flag = do_repeat ? CMD_FLAG_REPEAT : 0;
1553  	struct child_prog *child;
1554  	char *p;
1555  # if __GNUC__
1556  	/* Avoid longjmp clobbering */
1557  	(void) &i;
1558  	(void) &nextin;
1559  	(void) &child;
1560  # endif
1561  #endif	/* __U_BOOT__ */
1562  
1563  	nextin = 0;
1564  #ifndef __U_BOOT__
1565  	pi->pgrp = -1;
1566  #endif
1567  
1568  	/* Check if this is a simple builtin (not part of a pipe).
1569  	 * Builtins within pipes have to fork anyway, and are handled in
1570  	 * pseudo_exec.  "echo foo | read bar" doesn't work on bash, either.
1571  	 */
1572  	if (pi->num_progs == 1) child = & (pi->progs[0]);
1573  #ifndef __U_BOOT__
1574  	if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1575  		int squirrel[] = {-1, -1, -1};
1576  		int rcode;
1577  		debug_printf("non-subshell grouping\n");
1578  		setup_redirects(child, squirrel);
1579  		/* XXX could we merge code with following builtin case,
1580  		 * by creating a pseudo builtin that calls run_list_real? */
1581  		rcode = run_list_real(child->group);
1582  		restore_redirects(squirrel);
1583  #else
1584  		if (pi->num_progs == 1 && child->group) {
1585  		int rcode;
1586  		debug_printf("non-subshell grouping\n");
1587  		rcode = run_list_real(child->group);
1588  #endif
1589  		return rcode;
1590  	} else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1591  		for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
1592  		if (i!=0 && child->argv[i]==NULL) {
1593  			/* assignments, but no command: set the local environment */
1594  			for (i=0; child->argv[i]!=NULL; i++) {
1595  
1596  				/* Ok, this case is tricky.  We have to decide if this is a
1597  				 * local variable, or an already exported variable.  If it is
1598  				 * already exported, we have to export the new value.  If it is
1599  				 * not exported, we need only set this as a local variable.
1600  				 * This junk is all to decide whether or not to export this
1601  				 * variable. */
1602  				int export_me=0;
1603  				char *name, *value;
1604  				name = xstrdup(child->argv[i]);
1605  				debug_printf("Local environment set: %s\n", name);
1606  				value = strchr(name, '=');
1607  				if (value)
1608  					*value=0;
1609  #ifndef __U_BOOT__
1610  				if ( get_local_var(name)) {
1611  					export_me=1;
1612  				}
1613  #endif
1614  				free(name);
1615  				p = insert_var_value(child->argv[i]);
1616  				set_local_var(p, export_me);
1617  				if (p != child->argv[i]) free(p);
1618  			}
1619  			return EXIT_SUCCESS;   /* don't worry about errors in set_local_var() yet */
1620  		}
1621  		for (i = 0; is_assignment(child->argv[i]); i++) {
1622  			p = insert_var_value(child->argv[i]);
1623  #ifndef __U_BOOT__
1624  			putenv(strdup(p));
1625  #else
1626  			set_local_var(p, 0);
1627  #endif
1628  			if (p != child->argv[i]) {
1629  				child->sp--;
1630  				free(p);
1631  			}
1632  		}
1633  		if (child->sp) {
1634  			char * str = NULL;
1635  
1636  			str = make_string(child->argv + i,
1637  					  child->argv_nonnull + i);
1638  			parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1639  			free(str);
1640  			return last_return_code;
1641  		}
1642  #ifndef __U_BOOT__
1643  		for (x = bltins; x->cmd; x++) {
1644  			if (strcmp(child->argv[i], x->cmd) == 0 ) {
1645  				int squirrel[] = {-1, -1, -1};
1646  				int rcode;
1647  				if (x->function == builtin_exec && child->argv[i+1]==NULL) {
1648  					debug_printf("magic exec\n");
1649  					setup_redirects(child,NULL);
1650  					return EXIT_SUCCESS;
1651  				}
1652  				debug_printf("builtin inline %s\n", child->argv[0]);
1653  				/* XXX setup_redirects acts on file descriptors, not FILEs.
1654  				 * This is perfect for work that comes after exec().
1655  				 * Is it really safe for inline use?  Experimentally,
1656  				 * things seem to work with glibc. */
1657  				setup_redirects(child, squirrel);
1658  
1659  				child->argv += i;  /* XXX horrible hack */
1660  				rcode = x->function(child);
1661  				/* XXX restore hack so free() can work right */
1662  				child->argv -= i;
1663  				restore_redirects(squirrel);
1664  			}
1665  			return rcode;
1666  		}
1667  #else
1668  		/* check ";", because ,example , argv consist from
1669  		 * "help;flinfo" must not execute
1670  		 */
1671  		if (strchr(child->argv[i], ';')) {
1672  			printf("Unknown command '%s' - try 'help' or use "
1673  					"'run' command\n", child->argv[i]);
1674  			return -1;
1675  		}
1676  		/* Process the command */
1677  		return cmd_process(flag, child->argc, child->argv,
1678  				   &flag_repeat, NULL);
1679  #endif
1680  	}
1681  #ifndef __U_BOOT__
1682  
1683  	for (i = 0; i < pi->num_progs; i++) {
1684  		child = & (pi->progs[i]);
1685  
1686  		/* pipes are inserted between pairs of commands */
1687  		if ((i + 1) < pi->num_progs) {
1688  			if (pipe(pipefds)<0) perror_msg_and_die("pipe");
1689  			nextout = pipefds[1];
1690  		} else {
1691  			nextout=1;
1692  			pipefds[0] = -1;
1693  		}
1694  
1695  		/* XXX test for failed fork()? */
1696  		if (!(child->pid = fork())) {
1697  			/* Set the handling for job control signals back to the default.  */
1698  			signal(SIGINT, SIG_DFL);
1699  			signal(SIGQUIT, SIG_DFL);
1700  			signal(SIGTERM, SIG_DFL);
1701  			signal(SIGTSTP, SIG_DFL);
1702  			signal(SIGTTIN, SIG_DFL);
1703  			signal(SIGTTOU, SIG_DFL);
1704  			signal(SIGCHLD, SIG_DFL);
1705  
1706  			close_all();
1707  
1708  			if (nextin != 0) {
1709  				dup2(nextin, 0);
1710  				close(nextin);
1711  			}
1712  			if (nextout != 1) {
1713  				dup2(nextout, 1);
1714  				close(nextout);
1715  			}
1716  			if (pipefds[0]!=-1) {
1717  				close(pipefds[0]);  /* opposite end of our output pipe */
1718  			}
1719  
1720  			/* Like bash, explicit redirects override pipes,
1721  			 * and the pipe fd is available for dup'ing. */
1722  			setup_redirects(child,NULL);
1723  
1724  			if (interactive && pi->followup!=PIPE_BG) {
1725  				/* If we (the child) win the race, put ourselves in the process
1726  				 * group whose leader is the first process in this pipe. */
1727  				if (pi->pgrp < 0) {
1728  					pi->pgrp = getpid();
1729  				}
1730  				if (setpgid(0, pi->pgrp) == 0) {
1731  					tcsetpgrp(2, pi->pgrp);
1732  				}
1733  			}
1734  
1735  			pseudo_exec(child);
1736  		}
1737  
1738  
1739  		/* put our child in the process group whose leader is the
1740  		   first process in this pipe */
1741  		if (pi->pgrp < 0) {
1742  			pi->pgrp = child->pid;
1743  		}
1744  		/* Don't check for errors.  The child may be dead already,
1745  		 * in which case setpgid returns error code EACCES. */
1746  		setpgid(child->pid, pi->pgrp);
1747  
1748  		if (nextin != 0)
1749  			close(nextin);
1750  		if (nextout != 1)
1751  			close(nextout);
1752  
1753  		/* If there isn't another process, nextin is garbage
1754  		   but it doesn't matter */
1755  		nextin = pipefds[0];
1756  	}
1757  #endif
1758  	return -1;
1759  }
1760  
1761  static int run_list_real(struct pipe *pi)
1762  {
1763  	char *save_name = NULL;
1764  	char **list = NULL;
1765  	char **save_list = NULL;
1766  	struct pipe *rpipe;
1767  	int flag_rep = 0;
1768  #ifndef __U_BOOT__
1769  	int save_num_progs;
1770  #endif
1771  	int rcode=0, flag_skip=1;
1772  	int flag_restore = 0;
1773  	int if_code=0, next_if_code=0;  /* need double-buffer to handle elif */
1774  	reserved_style rmode, skip_more_in_this_rmode=RES_XXXX;
1775  	/* check syntax for "for" */
1776  	for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1777  		if ((rpipe->r_mode == RES_IN ||
1778  		    rpipe->r_mode == RES_FOR) &&
1779  		    (rpipe->next == NULL)) {
1780  				syntax();
1781  #ifdef __U_BOOT__
1782  				flag_repeat = 0;
1783  #endif
1784  				return 1;
1785  		}
1786  		if ((rpipe->r_mode == RES_IN &&
1787  			(rpipe->next->r_mode == RES_IN &&
1788  			rpipe->next->progs->argv != NULL))||
1789  			(rpipe->r_mode == RES_FOR &&
1790  			rpipe->next->r_mode != RES_IN)) {
1791  				syntax();
1792  #ifdef __U_BOOT__
1793  				flag_repeat = 0;
1794  #endif
1795  				return 1;
1796  		}
1797  	}
1798  	for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1799  		if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
1800  			pi->r_mode == RES_FOR) {
1801  #ifdef __U_BOOT__
1802  				/* check Ctrl-C */
1803  				ctrlc();
1804  				if ((had_ctrlc())) {
1805  					return 1;
1806  				}
1807  #endif
1808  				flag_restore = 0;
1809  				if (!rpipe) {
1810  					flag_rep = 0;
1811  					rpipe = pi;
1812  				}
1813  		}
1814  		rmode = pi->r_mode;
1815  		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);
1816  		if (rmode == skip_more_in_this_rmode && flag_skip) {
1817  			if (pi->followup == PIPE_SEQ) flag_skip=0;
1818  			continue;
1819  		}
1820  		flag_skip = 1;
1821  		skip_more_in_this_rmode = RES_XXXX;
1822  		if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
1823  		if (rmode == RES_THEN &&  if_code) continue;
1824  		if (rmode == RES_ELSE && !if_code) continue;
1825  		if (rmode == RES_ELIF && !if_code) break;
1826  		if (rmode == RES_FOR && pi->num_progs) {
1827  			if (!list) {
1828  				/* if no variable values after "in" we skip "for" */
1829  				if (!pi->next->progs->argv) continue;
1830  				/* create list of variable values */
1831  				list = make_list_in(pi->next->progs->argv,
1832  					pi->progs->argv[0]);
1833  				save_list = list;
1834  				save_name = pi->progs->argv[0];
1835  				pi->progs->argv[0] = NULL;
1836  				flag_rep = 1;
1837  			}
1838  			if (!(*list)) {
1839  				free(pi->progs->argv[0]);
1840  				free(save_list);
1841  				list = NULL;
1842  				flag_rep = 0;
1843  				pi->progs->argv[0] = save_name;
1844  #ifndef __U_BOOT__
1845  				pi->progs->glob_result.gl_pathv[0] =
1846  					pi->progs->argv[0];
1847  #endif
1848  				continue;
1849  			} else {
1850  				/* insert new value from list for variable */
1851  				if (pi->progs->argv[0])
1852  					free(pi->progs->argv[0]);
1853  				pi->progs->argv[0] = *list++;
1854  #ifndef __U_BOOT__
1855  				pi->progs->glob_result.gl_pathv[0] =
1856  					pi->progs->argv[0];
1857  #endif
1858  			}
1859  		}
1860  		if (rmode == RES_IN) continue;
1861  		if (rmode == RES_DO) {
1862  			if (!flag_rep) continue;
1863  		}
1864  		if (rmode == RES_DONE) {
1865  			if (flag_rep) {
1866  				flag_restore = 1;
1867  			} else {
1868  				rpipe = NULL;
1869  			}
1870  		}
1871  		if (pi->num_progs == 0) continue;
1872  #ifndef __U_BOOT__
1873  		save_num_progs = pi->num_progs; /* save number of programs */
1874  #endif
1875  		rcode = run_pipe_real(pi);
1876  		debug_printf("run_pipe_real returned %d\n",rcode);
1877  #ifndef __U_BOOT__
1878  		if (rcode!=-1) {
1879  			/* We only ran a builtin: rcode was set by the return value
1880  			 * of run_pipe_real(), and we don't need to wait for anything. */
1881  		} else if (pi->followup==PIPE_BG) {
1882  			/* XXX check bash's behavior with nontrivial pipes */
1883  			/* XXX compute jobid */
1884  			/* XXX what does bash do with attempts to background builtins? */
1885  			insert_bg_job(pi);
1886  			rcode = EXIT_SUCCESS;
1887  		} else {
1888  			if (interactive) {
1889  				/* move the new process group into the foreground */
1890  				if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1891  					perror_msg("tcsetpgrp-3");
1892  				rcode = checkjobs(pi);
1893  				/* move the shell to the foreground */
1894  				if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1895  					perror_msg("tcsetpgrp-4");
1896  			} else {
1897  				rcode = checkjobs(pi);
1898  			}
1899  			debug_printf("checkjobs returned %d\n",rcode);
1900  		}
1901  		last_return_code=rcode;
1902  #else
1903  		if (rcode < -1) {
1904  			last_return_code = -rcode - 2;
1905  			return -2;	/* exit */
1906  		}
1907  		last_return_code=(rcode == 0) ? 0 : 1;
1908  #endif
1909  #ifndef __U_BOOT__
1910  		pi->num_progs = save_num_progs; /* restore number of programs */
1911  #endif
1912  		if ( rmode == RES_IF || rmode == RES_ELIF )
1913  			next_if_code=rcode;  /* can be overwritten a number of times */
1914  		if (rmode == RES_WHILE)
1915  			flag_rep = !last_return_code;
1916  		if (rmode == RES_UNTIL)
1917  			flag_rep = last_return_code;
1918  		if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
1919  		     (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
1920  			skip_more_in_this_rmode=rmode;
1921  #ifndef __U_BOOT__
1922  		checkjobs(NULL);
1923  #endif
1924  	}
1925  	return rcode;
1926  }
1927  
1928  /* broken, of course, but OK for testing */
1929  static char *indenter(int i)
1930  {
1931  	static char blanks[]="                                    ";
1932  	return &blanks[sizeof(blanks)-i-1];
1933  }
1934  
1935  /* return code is the exit status of the pipe */
1936  static int free_pipe(struct pipe *pi, int indent)
1937  {
1938  	char **p;
1939  	struct child_prog *child;
1940  #ifndef __U_BOOT__
1941  	struct redir_struct *r, *rnext;
1942  #endif
1943  	int a, i, ret_code=0;
1944  	char *ind = indenter(indent);
1945  
1946  #ifndef __U_BOOT__
1947  	if (pi->stopped_progs > 0)
1948  		return ret_code;
1949  	final_printf("%s run pipe: (pid %d)\n",ind,getpid());
1950  #endif
1951  	for (i=0; i<pi->num_progs; i++) {
1952  		child = &pi->progs[i];
1953  		final_printf("%s  command %d:\n",ind,i);
1954  		if (child->argv) {
1955  			for (a=0,p=child->argv; *p; a++,p++) {
1956  				final_printf("%s   argv[%d] = %s\n",ind,a,*p);
1957  			}
1958  #ifndef __U_BOOT__
1959  			globfree(&child->glob_result);
1960  #else
1961  			for (a = 0; a < child->argc; a++) {
1962  				free(child->argv[a]);
1963  			}
1964  			free(child->argv);
1965  			free(child->argv_nonnull);
1966  			child->argc = 0;
1967  #endif
1968  			child->argv=NULL;
1969  		} else if (child->group) {
1970  #ifndef __U_BOOT__
1971  			final_printf("%s   begin group (subshell:%d)\n",ind, child->subshell);
1972  #endif
1973  			ret_code = free_pipe_list(child->group,indent+3);
1974  			final_printf("%s   end group\n",ind);
1975  		} else {
1976  			final_printf("%s   (nil)\n",ind);
1977  		}
1978  #ifndef __U_BOOT__
1979  		for (r=child->redirects; r; r=rnext) {
1980  			final_printf("%s   redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
1981  			if (r->dup == -1) {
1982  				/* guard against the case >$FOO, where foo is unset or blank */
1983  				if (r->word.gl_pathv) {
1984  					final_printf(" %s\n", *r->word.gl_pathv);
1985  					globfree(&r->word);
1986  				}
1987  			} else {
1988  				final_printf("&%d\n", r->dup);
1989  			}
1990  			rnext=r->next;
1991  			free(r);
1992  		}
1993  		child->redirects=NULL;
1994  #endif
1995  	}
1996  	free(pi->progs);   /* children are an array, they get freed all at once */
1997  	pi->progs=NULL;
1998  	return ret_code;
1999  }
2000  
2001  static int free_pipe_list(struct pipe *head, int indent)
2002  {
2003  	int rcode=0;   /* if list has no members */
2004  	struct pipe *pi, *next;
2005  	char *ind = indenter(indent);
2006  	for (pi=head; pi; pi=next) {
2007  		final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
2008  		rcode = free_pipe(pi, indent);
2009  		final_printf("%s pipe followup code %d\n", ind, pi->followup);
2010  		next=pi->next;
2011  		pi->next=NULL;
2012  		free(pi);
2013  	}
2014  	return rcode;
2015  }
2016  
2017  /* Select which version we will use */
2018  static int run_list(struct pipe *pi)
2019  {
2020  	int rcode=0;
2021  #ifndef __U_BOOT__
2022  	if (fake_mode==0) {
2023  #endif
2024  		rcode = run_list_real(pi);
2025  #ifndef __U_BOOT__
2026  	}
2027  #endif
2028  	/* free_pipe_list has the side effect of clearing memory
2029  	 * In the long run that function can be merged with run_list_real,
2030  	 * but doing that now would hobble the debugging effort. */
2031  	free_pipe_list(pi,0);
2032  	return rcode;
2033  }
2034  
2035  /* The API for glob is arguably broken.  This routine pushes a non-matching
2036   * string into the output structure, removing non-backslashed backslashes.
2037   * If someone can prove me wrong, by performing this function within the
2038   * original glob(3) api, feel free to rewrite this routine into oblivion.
2039   * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
2040   * XXX broken if the last character is '\\', check that before calling.
2041   */
2042  #ifndef __U_BOOT__
2043  static int globhack(const char *src, int flags, glob_t *pglob)
2044  {
2045  	int cnt=0, pathc;
2046  	const char *s;
2047  	char *dest;
2048  	for (cnt=1, s=src; s && *s; s++) {
2049  		if (*s == '\\') s++;
2050  		cnt++;
2051  	}
2052  	dest = malloc(cnt);
2053  	if (!dest) return GLOB_NOSPACE;
2054  	if (!(flags & GLOB_APPEND)) {
2055  		pglob->gl_pathv=NULL;
2056  		pglob->gl_pathc=0;
2057  		pglob->gl_offs=0;
2058  		pglob->gl_offs=0;
2059  	}
2060  	pathc = ++pglob->gl_pathc;
2061  	pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
2062  	if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
2063  	pglob->gl_pathv[pathc-1]=dest;
2064  	pglob->gl_pathv[pathc]=NULL;
2065  	for (s=src; s && *s; s++, dest++) {
2066  		if (*s == '\\') s++;
2067  		*dest = *s;
2068  	}
2069  	*dest='\0';
2070  	return 0;
2071  }
2072  
2073  /* XXX broken if the last character is '\\', check that before calling */
2074  static int glob_needed(const char *s)
2075  {
2076  	for (; *s; s++) {
2077  		if (*s == '\\') s++;
2078  		if (strchr("*[?",*s)) return 1;
2079  	}
2080  	return 0;
2081  }
2082  
2083  #if 0
2084  static void globprint(glob_t *pglob)
2085  {
2086  	int i;
2087  	debug_printf("glob_t at %p:\n", pglob);
2088  	debug_printf("  gl_pathc=%d  gl_pathv=%p  gl_offs=%d  gl_flags=%d\n",
2089  		pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
2090  	for (i=0; i<pglob->gl_pathc; i++)
2091  		debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
2092  			pglob->gl_pathv[i], pglob->gl_pathv[i]);
2093  }
2094  #endif
2095  
2096  static int xglob(o_string *dest, int flags, glob_t *pglob)
2097  {
2098  	int gr;
2099  
2100  	/* short-circuit for null word */
2101  	/* we can code this better when the debug_printf's are gone */
2102  	if (dest->length == 0) {
2103  		if (dest->nonnull) {
2104  			/* bash man page calls this an "explicit" null */
2105  			gr = globhack(dest->data, flags, pglob);
2106  			debug_printf("globhack returned %d\n",gr);
2107  		} else {
2108  			return 0;
2109  		}
2110  	} else if (glob_needed(dest->data)) {
2111  		gr = glob(dest->data, flags, NULL, pglob);
2112  		debug_printf("glob returned %d\n",gr);
2113  		if (gr == GLOB_NOMATCH) {
2114  			/* quote removal, or more accurately, backslash removal */
2115  			gr = globhack(dest->data, flags, pglob);
2116  			debug_printf("globhack returned %d\n",gr);
2117  		}
2118  	} else {
2119  		gr = globhack(dest->data, flags, pglob);
2120  		debug_printf("globhack returned %d\n",gr);
2121  	}
2122  	if (gr == GLOB_NOSPACE)
2123  		error_msg_and_die("out of memory during glob");
2124  	if (gr != 0) { /* GLOB_ABORTED ? */
2125  		error_msg("glob(3) error %d",gr);
2126  	}
2127  	/* globprint(glob_target); */
2128  	return gr;
2129  }
2130  #endif
2131  
2132  #ifdef __U_BOOT__
2133  static char *get_dollar_var(char ch);
2134  #endif
2135  
2136  /* This is used to get/check local shell variables */
2137  char *get_local_var(const char *s)
2138  {
2139  	struct variables *cur;
2140  
2141  	if (!s)
2142  		return NULL;
2143  
2144  #ifdef __U_BOOT__
2145  	if (*s == '$')
2146  		return get_dollar_var(s[1]);
2147  #endif
2148  
2149  	for (cur = top_vars; cur; cur=cur->next)
2150  		if(strcmp(cur->name, s)==0)
2151  			return cur->value;
2152  	return NULL;
2153  }
2154  
2155  /* This is used to set local shell variables
2156     flg_export==0 if only local (not exporting) variable
2157     flg_export==1 if "new" exporting environ
2158     flg_export>1  if current startup environ (not call putenv()) */
2159  int set_local_var(const char *s, int flg_export)
2160  {
2161  	char *name, *value;
2162  	int result=0;
2163  	struct variables *cur;
2164  
2165  #ifdef __U_BOOT__
2166  	/* might be possible! */
2167  	if (!isalpha(*s))
2168  		return -1;
2169  #endif
2170  
2171  	name=strdup(s);
2172  
2173  #ifdef __U_BOOT__
2174  	if (env_get(name) != NULL) {
2175  		printf ("ERROR: "
2176  				"There is a global environment variable with the same name.\n");
2177  		free(name);
2178  		return -1;
2179  	}
2180  #endif
2181  	/* Assume when we enter this function that we are already in
2182  	 * NAME=VALUE format.  So the first order of business is to
2183  	 * split 's' on the '=' into 'name' and 'value' */
2184  	value = strchr(name, '=');
2185  	if (value == NULL || *(value + 1) == 0) {
2186  		free(name);
2187  		return -1;
2188  	}
2189  	*value++ = 0;
2190  
2191  	for(cur = top_vars; cur; cur = cur->next) {
2192  		if(strcmp(cur->name, name)==0)
2193  			break;
2194  	}
2195  
2196  	if(cur) {
2197  		if(strcmp(cur->value, value)==0) {
2198  			if(flg_export>0 && cur->flg_export==0)
2199  				cur->flg_export=flg_export;
2200  			else
2201  				result++;
2202  		} else {
2203  			if(cur->flg_read_only) {
2204  				error_msg("%s: readonly variable", name);
2205  				result = -1;
2206  			} else {
2207  				if(flg_export>0 || cur->flg_export>1)
2208  					cur->flg_export=1;
2209  				free(cur->value);
2210  
2211  				cur->value = strdup(value);
2212  			}
2213  		}
2214  	} else {
2215  		cur = malloc(sizeof(struct variables));
2216  		if(!cur) {
2217  			result = -1;
2218  		} else {
2219  			cur->name = strdup(name);
2220  			if (cur->name == NULL) {
2221  				free(cur);
2222  				result = -1;
2223  			} else {
2224  				struct variables *bottom = top_vars;
2225  				cur->value = strdup(value);
2226  				cur->next = NULL;
2227  				cur->flg_export = flg_export;
2228  				cur->flg_read_only = 0;
2229  				while(bottom->next) bottom=bottom->next;
2230  				bottom->next = cur;
2231  			}
2232  		}
2233  	}
2234  
2235  #ifndef __U_BOOT__
2236  	if(result==0 && cur->flg_export==1) {
2237  		*(value-1) = '=';
2238  		result = putenv(name);
2239  	} else {
2240  #endif
2241  		free(name);
2242  #ifndef __U_BOOT__
2243  		if(result>0)            /* equivalent to previous set */
2244  			result = 0;
2245  	}
2246  #endif
2247  	return result;
2248  }
2249  
2250  void unset_local_var(const char *name)
2251  {
2252  	struct variables *cur;
2253  
2254  	if (name) {
2255  		for (cur = top_vars; cur; cur=cur->next) {
2256  			if(strcmp(cur->name, name)==0)
2257  				break;
2258  		}
2259  		if (cur != NULL) {
2260  			struct variables *next = top_vars;
2261  			if(cur->flg_read_only) {
2262  				error_msg("%s: readonly variable", name);
2263  				return;
2264  			} else {
2265  #ifndef __U_BOOT__
2266  				if(cur->flg_export)
2267  					unenv_set(cur->name);
2268  #endif
2269  				free(cur->name);
2270  				free(cur->value);
2271  				while (next->next != cur)
2272  					next = next->next;
2273  				next->next = cur->next;
2274  			}
2275  			free(cur);
2276  		}
2277  	}
2278  }
2279  
2280  static int is_assignment(const char *s)
2281  {
2282  	if (s == NULL)
2283  		return 0;
2284  
2285  	if (!isalpha(*s)) return 0;
2286  	++s;
2287  	while(isalnum(*s) || *s=='_') ++s;
2288  	return *s=='=';
2289  }
2290  
2291  #ifndef __U_BOOT__
2292  /* the src parameter allows us to peek forward to a possible &n syntax
2293   * for file descriptor duplication, e.g., "2>&1".
2294   * Return code is 0 normally, 1 if a syntax error is detected in src.
2295   * Resource errors (in xmalloc) cause the process to exit */
2296  static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
2297  	struct in_str *input)
2298  {
2299  	struct child_prog *child=ctx->child;
2300  	struct redir_struct *redir = child->redirects;
2301  	struct redir_struct *last_redir=NULL;
2302  
2303  	/* Create a new redir_struct and drop it onto the end of the linked list */
2304  	while(redir) {
2305  		last_redir=redir;
2306  		redir=redir->next;
2307  	}
2308  	redir = xmalloc(sizeof(struct redir_struct));
2309  	redir->next=NULL;
2310  	redir->word.gl_pathv=NULL;
2311  	if (last_redir) {
2312  		last_redir->next=redir;
2313  	} else {
2314  		child->redirects=redir;
2315  	}
2316  
2317  	redir->type=style;
2318  	redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
2319  
2320  	debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
2321  
2322  	/* Check for a '2>&1' type redirect */
2323  	redir->dup = redirect_dup_num(input);
2324  	if (redir->dup == -2) return 1;  /* syntax error */
2325  	if (redir->dup != -1) {
2326  		/* Erik had a check here that the file descriptor in question
2327  		 * is legit; I postpone that to "run time"
2328  		 * A "-" representation of "close me" shows up as a -3 here */
2329  		debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
2330  	} else {
2331  		/* We do _not_ try to open the file that src points to,
2332  		 * since we need to return and let src be expanded first.
2333  		 * Set ctx->pending_redirect, so we know what to do at the
2334  		 * end of the next parsed word.
2335  		 */
2336  		ctx->pending_redirect = redir;
2337  	}
2338  	return 0;
2339  }
2340  #endif
2341  
2342  static struct pipe *new_pipe(void)
2343  {
2344  	struct pipe *pi;
2345  	pi = xmalloc(sizeof(struct pipe));
2346  	pi->num_progs = 0;
2347  	pi->progs = NULL;
2348  	pi->next = NULL;
2349  	pi->followup = 0;  /* invalid */
2350  	pi->r_mode = RES_NONE;
2351  	return pi;
2352  }
2353  
2354  static void initialize_context(struct p_context *ctx)
2355  {
2356  	ctx->pipe=NULL;
2357  #ifndef __U_BOOT__
2358  	ctx->pending_redirect=NULL;
2359  #endif
2360  	ctx->child=NULL;
2361  	ctx->list_head=new_pipe();
2362  	ctx->pipe=ctx->list_head;
2363  	ctx->w=RES_NONE;
2364  	ctx->stack=NULL;
2365  #ifdef __U_BOOT__
2366  	ctx->old_flag=0;
2367  #endif
2368  	done_command(ctx);   /* creates the memory for working child */
2369  }
2370  
2371  /* normal return is 0
2372   * if a reserved word is found, and processed, return 1
2373   * should handle if, then, elif, else, fi, for, while, until, do, done.
2374   * case, function, and select are obnoxious, save those for later.
2375   */
2376  struct reserved_combo {
2377  	char *literal;
2378  	int code;
2379  	long flag;
2380  };
2381  /* Mostly a list of accepted follow-up reserved words.
2382   * FLAG_END means we are done with the sequence, and are ready
2383   * to turn the compound list into a command.
2384   * FLAG_START means the word must start a new compound list.
2385   */
2386  static struct reserved_combo reserved_list[] = {
2387  	{ "if",    RES_IF,    FLAG_THEN | FLAG_START },
2388  	{ "then",  RES_THEN,  FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2389  	{ "elif",  RES_ELIF,  FLAG_THEN },
2390  	{ "else",  RES_ELSE,  FLAG_FI   },
2391  	{ "fi",    RES_FI,    FLAG_END  },
2392  	{ "for",   RES_FOR,   FLAG_IN   | FLAG_START },
2393  	{ "while", RES_WHILE, FLAG_DO   | FLAG_START },
2394  	{ "until", RES_UNTIL, FLAG_DO   | FLAG_START },
2395  	{ "in",    RES_IN,    FLAG_DO   },
2396  	{ "do",    RES_DO,    FLAG_DONE },
2397  	{ "done",  RES_DONE,  FLAG_END  }
2398  };
2399  #define NRES (sizeof(reserved_list)/sizeof(struct reserved_combo))
2400  
2401  static int reserved_word(o_string *dest, struct p_context *ctx)
2402  {
2403  	struct reserved_combo *r;
2404  	for (r=reserved_list;
2405  		r<reserved_list+NRES; r++) {
2406  		if (strcmp(dest->data, r->literal) == 0) {
2407  			debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2408  			if (r->flag & FLAG_START) {
2409  				struct p_context *new = xmalloc(sizeof(struct p_context));
2410  				debug_printf("push stack\n");
2411  				if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2412  					syntax();
2413  					free(new);
2414  					ctx->w = RES_SNTX;
2415  					b_reset(dest);
2416  					return 1;
2417  				}
2418  				*new = *ctx;   /* physical copy */
2419  				initialize_context(ctx);
2420  				ctx->stack=new;
2421  			} else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2422  				syntax();
2423  				ctx->w = RES_SNTX;
2424  				b_reset(dest);
2425  				return 1;
2426  			}
2427  			ctx->w=r->code;
2428  			ctx->old_flag = r->flag;
2429  			if (ctx->old_flag & FLAG_END) {
2430  				struct p_context *old;
2431  				debug_printf("pop stack\n");
2432  				done_pipe(ctx,PIPE_SEQ);
2433  				old = ctx->stack;
2434  				old->child->group = ctx->list_head;
2435  #ifndef __U_BOOT__
2436  				old->child->subshell = 0;
2437  #endif
2438  				*ctx = *old;   /* physical copy */
2439  				free(old);
2440  			}
2441  			b_reset (dest);
2442  			return 1;
2443  		}
2444  	}
2445  	return 0;
2446  }
2447  
2448  /* normal return is 0.
2449   * Syntax or xglob errors return 1. */
2450  static int done_word(o_string *dest, struct p_context *ctx)
2451  {
2452  	struct child_prog *child=ctx->child;
2453  #ifndef __U_BOOT__
2454  	glob_t *glob_target;
2455  	int gr, flags = 0;
2456  #else
2457  	char *str, *s;
2458  	int argc, cnt;
2459  #endif
2460  
2461  	debug_printf("done_word: %s %p\n", dest->data, child);
2462  	if (dest->length == 0 && !dest->nonnull) {
2463  		debug_printf("  true null, ignored\n");
2464  		return 0;
2465  	}
2466  #ifndef __U_BOOT__
2467  	if (ctx->pending_redirect) {
2468  		glob_target = &ctx->pending_redirect->word;
2469  	} else {
2470  #endif
2471  		if (child->group) {
2472  			syntax();
2473  			return 1;  /* syntax error, groups and arglists don't mix */
2474  		}
2475  		if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2476  			debug_printf("checking %s for reserved-ness\n",dest->data);
2477  			if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2478  		}
2479  #ifndef __U_BOOT__
2480  		glob_target = &child->glob_result;
2481  		if (child->argv) flags |= GLOB_APPEND;
2482  #else
2483  		for (cnt = 1, s = dest->data; s && *s; s++) {
2484  			if (*s == '\\') s++;
2485  			cnt++;
2486  		}
2487  		str = malloc(cnt);
2488  		if (!str) return 1;
2489  		if ( child->argv == NULL) {
2490  			child->argc=0;
2491  		}
2492  		argc = ++child->argc;
2493  		child->argv = realloc(child->argv, (argc+1)*sizeof(*child->argv));
2494  		if (child->argv == NULL) {
2495  			free(str);
2496  			return 1;
2497  		}
2498  		child->argv_nonnull = realloc(child->argv_nonnull,
2499  					(argc+1)*sizeof(*child->argv_nonnull));
2500  		if (child->argv_nonnull == NULL) {
2501  			free(str);
2502  			return 1;
2503  		}
2504  		child->argv[argc-1]=str;
2505  		child->argv_nonnull[argc-1] = dest->nonnull;
2506  		child->argv[argc]=NULL;
2507  		child->argv_nonnull[argc] = 0;
2508  		for (s = dest->data; s && *s; s++,str++) {
2509  			if (*s == '\\') s++;
2510  			*str = *s;
2511  		}
2512  		*str = '\0';
2513  #endif
2514  #ifndef __U_BOOT__
2515  	}
2516  	gr = xglob(dest, flags, glob_target);
2517  	if (gr != 0) return 1;
2518  #endif
2519  
2520  	b_reset(dest);
2521  #ifndef __U_BOOT__
2522  	if (ctx->pending_redirect) {
2523  		ctx->pending_redirect=NULL;
2524  		if (glob_target->gl_pathc != 1) {
2525  			error_msg("ambiguous redirect");
2526  			return 1;
2527  		}
2528  	} else {
2529  		child->argv = glob_target->gl_pathv;
2530  	}
2531  #endif
2532  	if (ctx->w == RES_FOR) {
2533  		done_word(dest,ctx);
2534  		done_pipe(ctx,PIPE_SEQ);
2535  	}
2536  	return 0;
2537  }
2538  
2539  /* The only possible error here is out of memory, in which case
2540   * xmalloc exits. */
2541  static int done_command(struct p_context *ctx)
2542  {
2543  	/* The child is really already in the pipe structure, so
2544  	 * advance the pipe counter and make a new, null child.
2545  	 * Only real trickiness here is that the uncommitted
2546  	 * child structure, to which ctx->child points, is not
2547  	 * counted in pi->num_progs. */
2548  	struct pipe *pi=ctx->pipe;
2549  	struct child_prog *prog=ctx->child;
2550  
2551  	if (prog && prog->group == NULL
2552  		 && prog->argv == NULL
2553  #ifndef __U_BOOT__
2554  		 && prog->redirects == NULL) {
2555  #else
2556  										) {
2557  #endif
2558  		debug_printf("done_command: skipping null command\n");
2559  		return 0;
2560  	} else if (prog) {
2561  		pi->num_progs++;
2562  		debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2563  	} else {
2564  		debug_printf("done_command: initializing\n");
2565  	}
2566  	pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2567  
2568  	prog = pi->progs + pi->num_progs;
2569  #ifndef __U_BOOT__
2570  	prog->redirects = NULL;
2571  #endif
2572  	prog->argv = NULL;
2573  	prog->argv_nonnull = NULL;
2574  #ifndef __U_BOOT__
2575  	prog->is_stopped = 0;
2576  #endif
2577  	prog->group = NULL;
2578  #ifndef __U_BOOT__
2579  	prog->glob_result.gl_pathv = NULL;
2580  	prog->family = pi;
2581  #endif
2582  	prog->sp = 0;
2583  	ctx->child = prog;
2584  	prog->type = ctx->type;
2585  
2586  	/* but ctx->pipe and ctx->list_head remain unchanged */
2587  	return 0;
2588  }
2589  
2590  static int done_pipe(struct p_context *ctx, pipe_style type)
2591  {
2592  	struct pipe *new_p;
2593  	done_command(ctx);  /* implicit closure of previous command */
2594  	debug_printf("done_pipe, type %d\n", type);
2595  	ctx->pipe->followup = type;
2596  	ctx->pipe->r_mode = ctx->w;
2597  	new_p=new_pipe();
2598  	ctx->pipe->next = new_p;
2599  	ctx->pipe = new_p;
2600  	ctx->child = NULL;
2601  	done_command(ctx);  /* set up new pipe to accept commands */
2602  	return 0;
2603  }
2604  
2605  #ifndef __U_BOOT__
2606  /* peek ahead in the in_str to find out if we have a "&n" construct,
2607   * as in "2>&1", that represents duplicating a file descriptor.
2608   * returns either -2 (syntax error), -1 (no &), or the number found.
2609   */
2610  static int redirect_dup_num(struct in_str *input)
2611  {
2612  	int ch, d=0, ok=0;
2613  	ch = b_peek(input);
2614  	if (ch != '&') return -1;
2615  
2616  	b_getch(input);  /* get the & */
2617  	ch=b_peek(input);
2618  	if (ch == '-') {
2619  		b_getch(input);
2620  		return -3;  /* "-" represents "close me" */
2621  	}
2622  	while (isdigit(ch)) {
2623  		d = d*10+(ch-'0');
2624  		ok=1;
2625  		b_getch(input);
2626  		ch = b_peek(input);
2627  	}
2628  	if (ok) return d;
2629  
2630  	error_msg("ambiguous redirect");
2631  	return -2;
2632  }
2633  
2634  /* If a redirect is immediately preceded by a number, that number is
2635   * supposed to tell which file descriptor to redirect.  This routine
2636   * looks for such preceding numbers.  In an ideal world this routine
2637   * needs to handle all the following classes of redirects...
2638   *     echo 2>foo     # redirects fd  2 to file "foo", nothing passed to echo
2639   *     echo 49>foo    # redirects fd 49 to file "foo", nothing passed to echo
2640   *     echo -2>foo    # redirects fd  1 to file "foo",    "-2" passed to echo
2641   *     echo 49x>foo   # redirects fd  1 to file "foo",   "49x" passed to echo
2642   * A -1 output from this program means no valid number was found, so the
2643   * caller should use the appropriate default for this redirection.
2644   */
2645  static int redirect_opt_num(o_string *o)
2646  {
2647  	int num;
2648  
2649  	if (o->length==0) return -1;
2650  	for(num=0; num<o->length; num++) {
2651  		if (!isdigit(*(o->data+num))) {
2652  			return -1;
2653  		}
2654  	}
2655  	/* reuse num (and save an int) */
2656  	num=atoi(o->data);
2657  	b_reset(o);
2658  	return num;
2659  }
2660  
2661  FILE *generate_stream_from_list(struct pipe *head)
2662  {
2663  	FILE *pf;
2664  #if 1
2665  	int pid, channel[2];
2666  	if (pipe(channel)<0) perror_msg_and_die("pipe");
2667  	pid=fork();
2668  	if (pid<0) {
2669  		perror_msg_and_die("fork");
2670  	} else if (pid==0) {
2671  		close(channel[0]);
2672  		if (channel[1] != 1) {
2673  			dup2(channel[1],1);
2674  			close(channel[1]);
2675  		}
2676  #if 0
2677  #define SURROGATE "surrogate response"
2678  		write(1,SURROGATE,sizeof(SURROGATE));
2679  		_exit(run_list(head));
2680  #else
2681  		_exit(run_list_real(head));   /* leaks memory */
2682  #endif
2683  	}
2684  	debug_printf("forked child %d\n",pid);
2685  	close(channel[1]);
2686  	pf = fdopen(channel[0],"r");
2687  	debug_printf("pipe on FILE *%p\n",pf);
2688  #else
2689  	free_pipe_list(head,0);
2690  	pf=popen("echo surrogate response","r");
2691  	debug_printf("started fake pipe on FILE *%p\n",pf);
2692  #endif
2693  	return pf;
2694  }
2695  
2696  /* this version hacked for testing purposes */
2697  /* return code is exit status of the process that is run. */
2698  static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2699  {
2700  	int retcode;
2701  	o_string result=NULL_O_STRING;
2702  	struct p_context inner;
2703  	FILE *p;
2704  	struct in_str pipe_str;
2705  	initialize_context(&inner);
2706  
2707  	/* recursion to generate command */
2708  	retcode = parse_stream(&result, &inner, input, subst_end);
2709  	if (retcode != 0) return retcode;  /* syntax error or EOF */
2710  	done_word(&result, &inner);
2711  	done_pipe(&inner, PIPE_SEQ);
2712  	b_free(&result);
2713  
2714  	p=generate_stream_from_list(inner.list_head);
2715  	if (p==NULL) return 1;
2716  	mark_open(fileno(p));
2717  	setup_file_in_str(&pipe_str, p);
2718  
2719  	/* now send results of command back into original context */
2720  	retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2721  	/* XXX In case of a syntax error, should we try to kill the child?
2722  	 * That would be tough to do right, so just read until EOF. */
2723  	if (retcode == 1) {
2724  		while (b_getch(&pipe_str)!=EOF) { /* discard */ };
2725  	}
2726  
2727  	debug_printf("done reading from pipe, pclose()ing\n");
2728  	/* This is the step that wait()s for the child.  Should be pretty
2729  	 * safe, since we just read an EOF from its stdout.  We could try
2730  	 * to better, by using wait(), and keeping track of background jobs
2731  	 * at the same time.  That would be a lot of work, and contrary
2732  	 * to the KISS philosophy of this program. */
2733  	mark_closed(fileno(p));
2734  	retcode=pclose(p);
2735  	free_pipe_list(inner.list_head,0);
2736  	debug_printf("pclosed, retcode=%d\n",retcode);
2737  	/* XXX this process fails to trim a single trailing newline */
2738  	return retcode;
2739  }
2740  
2741  static int parse_group(o_string *dest, struct p_context *ctx,
2742  	struct in_str *input, int ch)
2743  {
2744  	int rcode, endch=0;
2745  	struct p_context sub;
2746  	struct child_prog *child = ctx->child;
2747  	if (child->argv) {
2748  		syntax();
2749  		return 1;  /* syntax error, groups and arglists don't mix */
2750  	}
2751  	initialize_context(&sub);
2752  	switch(ch) {
2753  		case '(': endch=')'; child->subshell=1; break;
2754  		case '{': endch='}'; break;
2755  		default: syntax();   /* really logic error */
2756  	}
2757  	rcode=parse_stream(dest,&sub,input,endch);
2758  	done_word(dest,&sub); /* finish off the final word in the subcontext */
2759  	done_pipe(&sub, PIPE_SEQ);  /* and the final command there, too */
2760  	child->group = sub.list_head;
2761  	return rcode;
2762  	/* child remains "open", available for possible redirects */
2763  }
2764  #endif
2765  
2766  /* basically useful version until someone wants to get fancier,
2767   * see the bash man page under "Parameter Expansion" */
2768  static char *lookup_param(char *src)
2769  {
2770  	char *p;
2771  	char *sep;
2772  	char *default_val = NULL;
2773  	int assign = 0;
2774  	int expand_empty = 0;
2775  
2776  	if (!src)
2777  		return NULL;
2778  
2779  	sep = strchr(src, ':');
2780  
2781  	if (sep) {
2782  		*sep = '\0';
2783  		if (*(sep + 1) == '-')
2784  			default_val = sep+2;
2785  		if (*(sep + 1) == '=') {
2786  			default_val = sep+2;
2787  			assign = 1;
2788  		}
2789  		if (*(sep + 1) == '+') {
2790  			default_val = sep+2;
2791  			expand_empty = 1;
2792  		}
2793  	}
2794  
2795  	p = env_get(src);
2796  	if (!p)
2797  		p = get_local_var(src);
2798  
2799  	if (!p || strlen(p) == 0) {
2800  		p = default_val;
2801  		if (assign) {
2802  			char *var = malloc(strlen(src)+strlen(default_val)+2);
2803  			if (var) {
2804  				sprintf(var, "%s=%s", src, default_val);
2805  				set_local_var(var, 0);
2806  			}
2807  			free(var);
2808  		}
2809  	} else if (expand_empty) {
2810  		p += strlen(p);
2811  	}
2812  
2813  	if (sep)
2814  		*sep = ':';
2815  
2816  	return p;
2817  }
2818  
2819  #ifdef __U_BOOT__
2820  static char *get_dollar_var(char ch)
2821  {
2822  	static char buf[40];
2823  
2824  	buf[0] = '\0';
2825  	switch (ch) {
2826  		case '?':
2827  			sprintf(buf, "%u", (unsigned int)last_return_code);
2828  			break;
2829  		default:
2830  			return NULL;
2831  	}
2832  	return buf;
2833  }
2834  #endif
2835  
2836  /* return code: 0 for OK, 1 for syntax error */
2837  static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2838  {
2839  #ifndef __U_BOOT__
2840  	int i, advance=0;
2841  #else
2842  	int advance=0;
2843  #endif
2844  #ifndef __U_BOOT__
2845  	char sep[]=" ";
2846  #endif
2847  	int ch = input->peek(input);  /* first character after the $ */
2848  	debug_printf("handle_dollar: ch=%c\n",ch);
2849  	if (isalpha(ch)) {
2850  		b_addchr(dest, SPECIAL_VAR_SYMBOL);
2851  		ctx->child->sp++;
2852  		while(ch=b_peek(input),isalnum(ch) || ch=='_') {
2853  			b_getch(input);
2854  			b_addchr(dest,ch);
2855  		}
2856  		b_addchr(dest, SPECIAL_VAR_SYMBOL);
2857  #ifndef __U_BOOT__
2858  	} else if (isdigit(ch)) {
2859  		i = ch-'0';  /* XXX is $0 special? */
2860  		if (i<global_argc) {
2861  			parse_string(dest, ctx, global_argv[i]); /* recursion */
2862  		}
2863  		advance = 1;
2864  #endif
2865  	} else switch (ch) {
2866  #ifndef __U_BOOT__
2867  		case '$':
2868  			b_adduint(dest,getpid());
2869  			advance = 1;
2870  			break;
2871  		case '!':
2872  			if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2873  			advance = 1;
2874  			break;
2875  #endif
2876  		case '?':
2877  #ifndef __U_BOOT__
2878  			b_adduint(dest,last_return_code);
2879  #else
2880  			ctx->child->sp++;
2881  			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2882  			b_addchr(dest, '$');
2883  			b_addchr(dest, '?');
2884  			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2885  #endif
2886  			advance = 1;
2887  			break;
2888  #ifndef __U_BOOT__
2889  		case '#':
2890  			b_adduint(dest,global_argc ? global_argc-1 : 0);
2891  			advance = 1;
2892  			break;
2893  #endif
2894  		case '{':
2895  			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2896  			ctx->child->sp++;
2897  			b_getch(input);
2898  			/* XXX maybe someone will try to escape the '}' */
2899  			while(ch=b_getch(input),ch!=EOF && ch!='}') {
2900  				b_addchr(dest,ch);
2901  			}
2902  			if (ch != '}') {
2903  				syntax();
2904  				return 1;
2905  			}
2906  			b_addchr(dest, SPECIAL_VAR_SYMBOL);
2907  			break;
2908  #ifndef __U_BOOT__
2909  		case '(':
2910  			b_getch(input);
2911  			process_command_subs(dest, ctx, input, ')');
2912  			break;
2913  		case '*':
2914  			sep[0]=ifs[0];
2915  			for (i=1; i<global_argc; i++) {
2916  				parse_string(dest, ctx, global_argv[i]);
2917  				if (i+1 < global_argc) parse_string(dest, ctx, sep);
2918  			}
2919  			break;
2920  		case '@':
2921  		case '-':
2922  		case '_':
2923  			/* still unhandled, but should be eventually */
2924  			error_msg("unhandled syntax: $%c",ch);
2925  			return 1;
2926  			break;
2927  #endif
2928  		default:
2929  			b_addqchr(dest,'$',dest->quote);
2930  	}
2931  	/* Eat the character if the flag was set.  If the compiler
2932  	 * is smart enough, we could substitute "b_getch(input);"
2933  	 * for all the "advance = 1;" above, and also end up with
2934  	 * a nice size-optimized program.  Hah!  That'll be the day.
2935  	 */
2936  	if (advance) b_getch(input);
2937  	return 0;
2938  }
2939  
2940  #ifndef __U_BOOT__
2941  int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2942  {
2943  	struct in_str foo;
2944  	setup_string_in_str(&foo, src);
2945  	return parse_stream(dest, ctx, &foo, '\0');
2946  }
2947  #endif
2948  
2949  /* return code is 0 for normal exit, 1 for syntax error */
2950  static int parse_stream(o_string *dest, struct p_context *ctx,
2951  			struct in_str *input, int end_trigger)
2952  {
2953  	unsigned int ch, m;
2954  #ifndef __U_BOOT__
2955  	int redir_fd;
2956  	redir_type redir_style;
2957  #endif
2958  	int next;
2959  
2960  	/* Only double-quote state is handled in the state variable dest->quote.
2961  	 * A single-quote triggers a bypass of the main loop until its mate is
2962  	 * found.  When recursing, quote state is passed in via dest->quote. */
2963  
2964  	debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2965  	while ((ch=b_getch(input))!=EOF) {
2966  		m = map[ch];
2967  #ifdef __U_BOOT__
2968  		if (input->__promptme == 0) return 1;
2969  #endif
2970  		next = (ch == '\n') ? 0 : b_peek(input);
2971  
2972  		debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d - %c\n",
2973  			ch >= ' ' ? ch : '.', ch, m,
2974  			dest->quote, ctx->stack == NULL ? '*' : '.');
2975  
2976  		if (m==0 || ((m==1 || m==2) && dest->quote)) {
2977  			b_addqchr(dest, ch, dest->quote);
2978  		} else {
2979  			if (m==2) {  /* unquoted IFS */
2980  				if (done_word(dest, ctx)) {
2981  					return 1;
2982  				}
2983  				/* If we aren't performing a substitution, treat a newline as a
2984  				 * command separator.  */
2985  				if (end_trigger != '\0' && ch=='\n')
2986  					done_pipe(ctx,PIPE_SEQ);
2987  			}
2988  			if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2989  				debug_printf("leaving parse_stream (triggered)\n");
2990  				return 0;
2991  			}
2992  #if 0
2993  			if (ch=='\n') {
2994  				/* Yahoo!  Time to run with it! */
2995  				done_pipe(ctx,PIPE_SEQ);
2996  				run_list(ctx->list_head);
2997  				initialize_context(ctx);
2998  			}
2999  #endif
3000  			if (m!=2) switch (ch) {
3001  		case '#':
3002  			if (dest->length == 0 && !dest->quote) {
3003  				while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
3004  			} else {
3005  				b_addqchr(dest, ch, dest->quote);
3006  			}
3007  			break;
3008  		case '\\':
3009  			if (next == EOF) {
3010  				syntax();
3011  				return 1;
3012  			}
3013  			b_addqchr(dest, '\\', dest->quote);
3014  			b_addqchr(dest, b_getch(input), dest->quote);
3015  			break;
3016  		case '$':
3017  			if (handle_dollar(dest, ctx, input)!=0) return 1;
3018  			break;
3019  		case '\'':
3020  			dest->nonnull = 1;
3021  			while(ch=b_getch(input),ch!=EOF && ch!='\'') {
3022  #ifdef __U_BOOT__
3023  				if(input->__promptme == 0) return 1;
3024  #endif
3025  				b_addchr(dest,ch);
3026  			}
3027  			if (ch==EOF) {
3028  				syntax();
3029  				return 1;
3030  			}
3031  			break;
3032  		case '"':
3033  			dest->nonnull = 1;
3034  			dest->quote = !dest->quote;
3035  			break;
3036  #ifndef __U_BOOT__
3037  		case '`':
3038  			process_command_subs(dest, ctx, input, '`');
3039  			break;
3040  		case '>':
3041  			redir_fd = redirect_opt_num(dest);
3042  			done_word(dest, ctx);
3043  			redir_style=REDIRECT_OVERWRITE;
3044  			if (next == '>') {
3045  				redir_style=REDIRECT_APPEND;
3046  				b_getch(input);
3047  			} else if (next == '(') {
3048  				syntax();   /* until we support >(list) Process Substitution */
3049  				return 1;
3050  			}
3051  			setup_redirect(ctx, redir_fd, redir_style, input);
3052  			break;
3053  		case '<':
3054  			redir_fd = redirect_opt_num(dest);
3055  			done_word(dest, ctx);
3056  			redir_style=REDIRECT_INPUT;
3057  			if (next == '<') {
3058  				redir_style=REDIRECT_HEREIS;
3059  				b_getch(input);
3060  			} else if (next == '>') {
3061  				redir_style=REDIRECT_IO;
3062  				b_getch(input);
3063  			} else if (next == '(') {
3064  				syntax();   /* until we support <(list) Process Substitution */
3065  				return 1;
3066  			}
3067  			setup_redirect(ctx, redir_fd, redir_style, input);
3068  			break;
3069  #endif
3070  		case ';':
3071  			done_word(dest, ctx);
3072  			done_pipe(ctx,PIPE_SEQ);
3073  			break;
3074  		case '&':
3075  			done_word(dest, ctx);
3076  			if (next=='&') {
3077  				b_getch(input);
3078  				done_pipe(ctx,PIPE_AND);
3079  			} else {
3080  #ifndef __U_BOOT__
3081  				done_pipe(ctx,PIPE_BG);
3082  #else
3083  				syntax_err();
3084  				return 1;
3085  #endif
3086  			}
3087  			break;
3088  		case '|':
3089  			done_word(dest, ctx);
3090  			if (next=='|') {
3091  				b_getch(input);
3092  				done_pipe(ctx,PIPE_OR);
3093  			} else {
3094  				/* we could pick up a file descriptor choice here
3095  				 * with redirect_opt_num(), but bash doesn't do it.
3096  				 * "echo foo 2| cat" yields "foo 2". */
3097  #ifndef __U_BOOT__
3098  				done_command(ctx);
3099  #else
3100  				syntax_err();
3101  				return 1;
3102  #endif
3103  			}
3104  			break;
3105  #ifndef __U_BOOT__
3106  		case '(':
3107  		case '{':
3108  			if (parse_group(dest, ctx, input, ch)!=0) return 1;
3109  			break;
3110  		case ')':
3111  		case '}':
3112  			syntax();   /* Proper use of this character caught by end_trigger */
3113  			return 1;
3114  			break;
3115  #endif
3116  		case SUBSTED_VAR_SYMBOL:
3117  			dest->nonnull = 1;
3118  			while (ch = b_getch(input), ch != EOF &&
3119  			    ch != SUBSTED_VAR_SYMBOL) {
3120  				debug_printf("subst, pass=%d\n", ch);
3121  				if (input->__promptme == 0)
3122  					return 1;
3123  				b_addchr(dest, ch);
3124  			}
3125  			debug_printf("subst, term=%d\n", ch);
3126  			if (ch == EOF) {
3127  				syntax();
3128  				return 1;
3129  			}
3130  			break;
3131  		default:
3132  			syntax();   /* this is really an internal logic error */
3133  			return 1;
3134  			}
3135  		}
3136  	}
3137  	/* complain if quote?  No, maybe we just finished a command substitution
3138  	 * that was quoted.  Example:
3139  	 * $ echo "`cat foo` plus more"
3140  	 * and we just got the EOF generated by the subshell that ran "cat foo"
3141  	 * The only real complaint is if we got an EOF when end_trigger != '\0',
3142  	 * that is, we were really supposed to get end_trigger, and never got
3143  	 * one before the EOF.  Can't use the standard "syntax error" return code,
3144  	 * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
3145  	debug_printf("leaving parse_stream (EOF)\n");
3146  	if (end_trigger != '\0') return -1;
3147  	return 0;
3148  }
3149  
3150  static void mapset(const unsigned char *set, int code)
3151  {
3152  	const unsigned char *s;
3153  	for (s=set; *s; s++) map[*s] = code;
3154  }
3155  
3156  static void update_ifs_map(void)
3157  {
3158  	/* char *ifs and char map[256] are both globals. */
3159  	ifs = (uchar *)env_get("IFS");
3160  	if (ifs == NULL) ifs=(uchar *)" \t\n";
3161  	/* Precompute a list of 'flow through' behavior so it can be treated
3162  	 * quickly up front.  Computation is necessary because of IFS.
3163  	 * Special case handling of IFS == " \t\n" is not implemented.
3164  	 * The map[] array only really needs two bits each, and on most machines
3165  	 * that would be faster because of the reduced L1 cache footprint.
3166  	 */
3167  	memset(map,0,sizeof(map)); /* most characters flow through always */
3168  #ifndef __U_BOOT__
3169  	mapset((uchar *)"\\$'\"`", 3);      /* never flow through */
3170  	mapset((uchar *)"<>;&|(){}#", 1);   /* flow through if quoted */
3171  #else
3172  	{
3173  		uchar subst[2] = {SUBSTED_VAR_SYMBOL, 0};
3174  		mapset(subst, 3);       /* never flow through */
3175  	}
3176  	mapset((uchar *)"\\$'\"", 3);       /* never flow through */
3177  	mapset((uchar *)";&|#", 1);         /* flow through if quoted */
3178  #endif
3179  	mapset(ifs, 2);            /* also flow through if quoted */
3180  }
3181  
3182  /* most recursion does not come through here, the exeception is
3183   * from builtin_source() */
3184  static int parse_stream_outer(struct in_str *inp, int flag)
3185  {
3186  
3187  	struct p_context ctx;
3188  	o_string temp=NULL_O_STRING;
3189  	int rcode;
3190  #ifdef __U_BOOT__
3191  	int code = 1;
3192  #endif
3193  	do {
3194  		ctx.type = flag;
3195  		initialize_context(&ctx);
3196  		update_ifs_map();
3197  		if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset((uchar *)";$&|", 0);
3198  		inp->promptmode=1;
3199  		rcode = parse_stream(&temp, &ctx, inp,
3200  				     flag & FLAG_CONT_ON_NEWLINE ? -1 : '\n');
3201  #ifdef __U_BOOT__
3202  		if (rcode == 1) flag_repeat = 0;
3203  #endif
3204  		if (rcode != 1 && ctx.old_flag != 0) {
3205  			syntax();
3206  #ifdef __U_BOOT__
3207  			flag_repeat = 0;
3208  #endif
3209  		}
3210  		if (rcode != 1 && ctx.old_flag == 0) {
3211  			done_word(&temp, &ctx);
3212  			done_pipe(&ctx,PIPE_SEQ);
3213  #ifndef __U_BOOT__
3214  			run_list(ctx.list_head);
3215  #else
3216  			code = run_list(ctx.list_head);
3217  			if (code == -2) {	/* exit */
3218  				b_free(&temp);
3219  				code = 0;
3220  				/* XXX hackish way to not allow exit from main loop */
3221  				if (inp->peek == file_peek) {
3222  					printf("exit not allowed from main input shell.\n");
3223  					continue;
3224  				}
3225  				break;
3226  			}
3227  			if (code == -1)
3228  			    flag_repeat = 0;
3229  #endif
3230  		} else {
3231  			if (ctx.old_flag != 0) {
3232  				free(ctx.stack);
3233  				b_reset(&temp);
3234  			}
3235  #ifdef __U_BOOT__
3236  			if (inp->__promptme == 0) printf("<INTERRUPT>\n");
3237  			inp->__promptme = 1;
3238  #endif
3239  			temp.nonnull = 0;
3240  			temp.quote = 0;
3241  			inp->p = NULL;
3242  			free_pipe_list(ctx.list_head,0);
3243  		}
3244  		b_free(&temp);
3245  	/* loop on syntax errors, return on EOF */
3246  	} while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP) &&
3247  		(inp->peek != static_peek || b_peek(inp)));
3248  #ifndef __U_BOOT__
3249  	return 0;
3250  #else
3251  	return (code != 0) ? 1 : 0;
3252  #endif /* __U_BOOT__ */
3253  }
3254  
3255  #ifndef __U_BOOT__
3256  static int parse_string_outer(const char *s, int flag)
3257  #else
3258  int parse_string_outer(const char *s, int flag)
3259  #endif	/* __U_BOOT__ */
3260  {
3261  	struct in_str input;
3262  #ifdef __U_BOOT__
3263  	char *p = NULL;
3264  	int rcode;
3265  	if (!s)
3266  		return 1;
3267  	if (!*s)
3268  		return 0;
3269  	if (!(p = strchr(s, '\n')) || *++p) {
3270  		p = xmalloc(strlen(s) + 2);
3271  		strcpy(p, s);
3272  		strcat(p, "\n");
3273  		setup_string_in_str(&input, p);
3274  		rcode = parse_stream_outer(&input, flag);
3275  		free(p);
3276  		return rcode;
3277  	} else {
3278  #endif
3279  	setup_string_in_str(&input, s);
3280  	return parse_stream_outer(&input, flag);
3281  #ifdef __U_BOOT__
3282  	}
3283  #endif
3284  }
3285  
3286  #ifndef __U_BOOT__
3287  static int parse_file_outer(FILE *f)
3288  #else
3289  int parse_file_outer(void)
3290  #endif
3291  {
3292  	int rcode;
3293  	struct in_str input;
3294  #ifndef __U_BOOT__
3295  	setup_file_in_str(&input, f);
3296  #else
3297  	setup_file_in_str(&input);
3298  #endif
3299  	rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
3300  	return rcode;
3301  }
3302  
3303  #ifdef __U_BOOT__
3304  #ifdef CONFIG_NEEDS_MANUAL_RELOC
3305  static void u_boot_hush_reloc(void)
3306  {
3307  	unsigned long addr;
3308  	struct reserved_combo *r;
3309  
3310  	for (r=reserved_list; r<reserved_list+NRES; r++) {
3311  		addr = (ulong) (r->literal) + gd->reloc_off;
3312  		r->literal = (char *)addr;
3313  	}
3314  }
3315  #endif
3316  
3317  int u_boot_hush_start(void)
3318  {
3319  	if (top_vars == NULL) {
3320  		top_vars = malloc(sizeof(struct variables));
3321  		top_vars->name = "HUSH_VERSION";
3322  		top_vars->value = "0.01";
3323  		top_vars->next = NULL;
3324  		top_vars->flg_export = 0;
3325  		top_vars->flg_read_only = 1;
3326  #ifdef CONFIG_NEEDS_MANUAL_RELOC
3327  		u_boot_hush_reloc();
3328  #endif
3329  	}
3330  	return 0;
3331  }
3332  
3333  static void *xmalloc(size_t size)
3334  {
3335  	void *p = NULL;
3336  
3337  	if (!(p = malloc(size))) {
3338  	    printf("ERROR : memory not allocated\n");
3339  	    for(;;);
3340  	}
3341  	return p;
3342  }
3343  
3344  static void *xrealloc(void *ptr, size_t size)
3345  {
3346  	void *p = NULL;
3347  
3348  	if (!(p = realloc(ptr, size))) {
3349  	    printf("ERROR : memory not allocated\n");
3350  	    for(;;);
3351  	}
3352  	return p;
3353  }
3354  #endif /* __U_BOOT__ */
3355  
3356  #ifndef __U_BOOT__
3357  /* Make sure we have a controlling tty.  If we get started under a job
3358   * aware app (like bash for example), make sure we are now in charge so
3359   * we don't fight over who gets the foreground */
3360  static void setup_job_control(void)
3361  {
3362  	static pid_t shell_pgrp;
3363  	/* Loop until we are in the foreground.  */
3364  	while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
3365  		kill (- shell_pgrp, SIGTTIN);
3366  
3367  	/* Ignore interactive and job-control signals.  */
3368  	signal(SIGINT, SIG_IGN);
3369  	signal(SIGQUIT, SIG_IGN);
3370  	signal(SIGTERM, SIG_IGN);
3371  	signal(SIGTSTP, SIG_IGN);
3372  	signal(SIGTTIN, SIG_IGN);
3373  	signal(SIGTTOU, SIG_IGN);
3374  	signal(SIGCHLD, SIG_IGN);
3375  
3376  	/* Put ourselves in our own process group.  */
3377  	setsid();
3378  	shell_pgrp = getpid ();
3379  	setpgid (shell_pgrp, shell_pgrp);
3380  
3381  	/* Grab control of the terminal.  */
3382  	tcsetpgrp(shell_terminal, shell_pgrp);
3383  }
3384  
3385  int hush_main(int argc, char * const *argv)
3386  {
3387  	int opt;
3388  	FILE *input;
3389  	char **e = environ;
3390  
3391  	/* XXX what should these be while sourcing /etc/profile? */
3392  	global_argc = argc;
3393  	global_argv = argv;
3394  
3395  	/* (re?) initialize globals.  Sometimes hush_main() ends up calling
3396  	 * hush_main(), therefore we cannot rely on the BSS to zero out this
3397  	 * stuff.  Reset these to 0 every time. */
3398  	ifs = NULL;
3399  	/* map[] is taken care of with call to update_ifs_map() */
3400  	fake_mode = 0;
3401  	interactive = 0;
3402  	close_me_head = NULL;
3403  	last_bg_pid = 0;
3404  	job_list = NULL;
3405  	last_jobid = 0;
3406  
3407  	/* Initialize some more globals to non-zero values */
3408  	set_cwd();
3409  #ifdef CONFIG_FEATURE_COMMAND_EDITING
3410  	cmdedit_set_initial_prompt();
3411  #else
3412  	PS1 = NULL;
3413  #endif
3414  	PS2 = "> ";
3415  
3416  	/* initialize our shell local variables with the values
3417  	 * currently living in the environment */
3418  	if (e) {
3419  		for (; *e; e++)
3420  			set_local_var(*e, 2);   /* without call putenv() */
3421  	}
3422  
3423  	last_return_code=EXIT_SUCCESS;
3424  
3425  
3426  	if (argv[0] && argv[0][0] == '-') {
3427  		debug_printf("\nsourcing /etc/profile\n");
3428  		if ((input = fopen("/etc/profile", "r")) != NULL) {
3429  			mark_open(fileno(input));
3430  			parse_file_outer(input);
3431  			mark_closed(fileno(input));
3432  			fclose(input);
3433  		}
3434  	}
3435  	input=stdin;
3436  
3437  	while ((opt = getopt(argc, argv, "c:xif")) > 0) {
3438  		switch (opt) {
3439  			case 'c':
3440  				{
3441  					global_argv = argv+optind;
3442  					global_argc = argc-optind;
3443  					opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
3444  					goto final_return;
3445  				}
3446  				break;
3447  			case 'i':
3448  				interactive++;
3449  				break;
3450  			case 'f':
3451  				fake_mode++;
3452  				break;
3453  			default:
3454  #ifndef BB_VER
3455  				fprintf(stderr, "Usage: sh [FILE]...\n"
3456  						"   or: sh -c command [args]...\n\n");
3457  				exit(EXIT_FAILURE);
3458  #else
3459  				show_usage();
3460  #endif
3461  		}
3462  	}
3463  	/* A shell is interactive if the `-i' flag was given, or if all of
3464  	 * the following conditions are met:
3465  	 *	  no -c command
3466  	 *    no arguments remaining or the -s flag given
3467  	 *    standard input is a terminal
3468  	 *    standard output is a terminal
3469  	 *    Refer to Posix.2, the description of the `sh' utility. */
3470  	if (argv[optind]==NULL && input==stdin &&
3471  			isatty(fileno(stdin)) && isatty(fileno(stdout))) {
3472  		interactive++;
3473  	}
3474  
3475  	debug_printf("\ninteractive=%d\n", interactive);
3476  	if (interactive) {
3477  		/* Looks like they want an interactive shell */
3478  #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
3479  		printf( "\n\n" BB_BANNER " hush - the humble shell v0.01 (testing)\n");
3480  		printf( "Enter 'help' for a list of built-in commands.\n\n");
3481  #endif
3482  		setup_job_control();
3483  	}
3484  
3485  	if (argv[optind]==NULL) {
3486  		opt=parse_file_outer(stdin);
3487  		goto final_return;
3488  	}
3489  
3490  	debug_printf("\nrunning script '%s'\n", argv[optind]);
3491  	global_argv = argv+optind;
3492  	global_argc = argc-optind;
3493  	input = xfopen(argv[optind], "r");
3494  	opt = parse_file_outer(input);
3495  
3496  #ifdef CONFIG_FEATURE_CLEAN_UP
3497  	fclose(input);
3498  	if (cwd && cwd != unknown)
3499  		free((char*)cwd);
3500  	{
3501  		struct variables *cur, *tmp;
3502  		for(cur = top_vars; cur; cur = tmp) {
3503  			tmp = cur->next;
3504  			if (!cur->flg_read_only) {
3505  				free(cur->name);
3506  				free(cur->value);
3507  				free(cur);
3508  			}
3509  		}
3510  	}
3511  #endif
3512  
3513  final_return:
3514  	return(opt?opt:last_return_code);
3515  }
3516  #endif
3517  
3518  static char *insert_var_value(char *inp)
3519  {
3520  	return insert_var_value_sub(inp, 0);
3521  }
3522  
3523  static char *insert_var_value_sub(char *inp, int tag_subst)
3524  {
3525  	int res_str_len = 0;
3526  	int len;
3527  	int done = 0;
3528  	char *p, *p1, *res_str = NULL;
3529  
3530  	while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
3531  		/* check the beginning of the string for normal characters */
3532  		if (p != inp) {
3533  			/* copy any characters to the result string */
3534  			len = p - inp;
3535  			res_str = xrealloc(res_str, (res_str_len + len));
3536  			strncpy((res_str + res_str_len), inp, len);
3537  			res_str_len += len;
3538  		}
3539  		inp = ++p;
3540  		/* find the ending marker */
3541  		p = strchr(inp, SPECIAL_VAR_SYMBOL);
3542  		*p = '\0';
3543  		/* look up the value to substitute */
3544  		if ((p1 = lookup_param(inp))) {
3545  			if (tag_subst)
3546  				len = res_str_len + strlen(p1) + 2;
3547  			else
3548  				len = res_str_len + strlen(p1);
3549  			res_str = xrealloc(res_str, (1 + len));
3550  			if (tag_subst) {
3551  				/*
3552  				 * copy the variable value to the result
3553  				 * string
3554  				 */
3555  				strcpy((res_str + res_str_len + 1), p1);
3556  
3557  				/*
3558  				 * mark the replaced text to be accepted as
3559  				 * is
3560  				 */
3561  				res_str[res_str_len] = SUBSTED_VAR_SYMBOL;
3562  				res_str[res_str_len + 1 + strlen(p1)] =
3563  					SUBSTED_VAR_SYMBOL;
3564  			} else
3565  				/*
3566  				 * copy the variable value to the result
3567  				 * string
3568  				 */
3569  				strcpy((res_str + res_str_len), p1);
3570  
3571  			res_str_len = len;
3572  		}
3573  		*p = SPECIAL_VAR_SYMBOL;
3574  		inp = ++p;
3575  		done = 1;
3576  	}
3577  	if (done) {
3578  		res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
3579  		strcpy((res_str + res_str_len), inp);
3580  		while ((p = strchr(res_str, '\n'))) {
3581  			*p = ' ';
3582  		}
3583  	}
3584  	return (res_str == NULL) ? inp : res_str;
3585  }
3586  
3587  static char **make_list_in(char **inp, char *name)
3588  {
3589  	int len, i;
3590  	int name_len = strlen(name);
3591  	int n = 0;
3592  	char **list;
3593  	char *p1, *p2, *p3;
3594  
3595  	/* create list of variable values */
3596  	list = xmalloc(sizeof(*list));
3597  	for (i = 0; inp[i]; i++) {
3598  		p3 = insert_var_value(inp[i]);
3599  		p1 = p3;
3600  		while (*p1) {
3601  			if (*p1 == ' ') {
3602  				p1++;
3603  				continue;
3604  			}
3605  			if ((p2 = strchr(p1, ' '))) {
3606  				len = p2 - p1;
3607  			} else {
3608  				len = strlen(p1);
3609  				p2 = p1 + len;
3610  			}
3611  			/* we use n + 2 in realloc for list,because we add
3612  			 * new element and then we will add NULL element */
3613  			list = xrealloc(list, sizeof(*list) * (n + 2));
3614  			list[n] = xmalloc(2 + name_len + len);
3615  			strcpy(list[n], name);
3616  			strcat(list[n], "=");
3617  			strncat(list[n], p1, len);
3618  			list[n++][name_len + len + 1] = '\0';
3619  			p1 = p2;
3620  		}
3621  		if (p3 != inp[i]) free(p3);
3622  	}
3623  	list[n] = NULL;
3624  	return list;
3625  }
3626  
3627  /*
3628   * Make new string for parser
3629   * inp     - array of argument strings to flatten
3630   * nonnull - indicates argument was quoted when originally parsed
3631   */
3632  static char *make_string(char **inp, int *nonnull)
3633  {
3634  	char *p;
3635  	char *str = NULL;
3636  	int n;
3637  	int len = 2;
3638  	char *noeval_str;
3639  	int noeval = 0;
3640  
3641  	noeval_str = get_local_var("HUSH_NO_EVAL");
3642  	if (noeval_str != NULL && *noeval_str != '0' && *noeval_str != '\0')
3643  		noeval = 1;
3644  	for (n = 0; inp[n]; n++) {
3645  		p = insert_var_value_sub(inp[n], noeval);
3646  		str = xrealloc(str, (len + strlen(p) + (2 * nonnull[n])));
3647  		if (n) {
3648  			strcat(str, " ");
3649  		} else {
3650  			*str = '\0';
3651  		}
3652  		if (nonnull[n])
3653  			strcat(str, "'");
3654  		strcat(str, p);
3655  		if (nonnull[n])
3656  			strcat(str, "'");
3657  		len = strlen(str) + 3;
3658  		if (p != inp[n]) free(p);
3659  	}
3660  	len = strlen(str);
3661  	*(str + len) = '\n';
3662  	*(str + len + 1) = '\0';
3663  	return str;
3664  }
3665  
3666  #ifdef __U_BOOT__
3667  static int do_showvar(cmd_tbl_t *cmdtp, int flag, int argc,
3668  		      char * const argv[])
3669  {
3670  	int i, k;
3671  	int rcode = 0;
3672  	struct variables *cur;
3673  
3674  	if (argc == 1) {		/* Print all env variables	*/
3675  		for (cur = top_vars; cur; cur = cur->next) {
3676  			printf ("%s=%s\n", cur->name, cur->value);
3677  			if (ctrlc ()) {
3678  				puts ("\n ** Abort\n");
3679  				return 1;
3680  			}
3681  		}
3682  		return 0;
3683  	}
3684  	for (i = 1; i < argc; ++i) {	/* print single env variables	*/
3685  		char *name = argv[i];
3686  
3687  		k = -1;
3688  		for (cur = top_vars; cur; cur = cur->next) {
3689  			if(strcmp (cur->name, name) == 0) {
3690  				k = 0;
3691  				printf ("%s=%s\n", cur->name, cur->value);
3692  			}
3693  			if (ctrlc ()) {
3694  				puts ("\n ** Abort\n");
3695  				return 1;
3696  			}
3697  		}
3698  		if (k < 0) {
3699  			printf ("## Error: \"%s\" not defined\n", name);
3700  			rcode ++;
3701  		}
3702  	}
3703  	return rcode;
3704  }
3705  
3706  U_BOOT_CMD(
3707  	showvar, CONFIG_SYS_MAXARGS, 1,	do_showvar,
3708  	"print local hushshell variables",
3709  	"\n    - print values of all hushshell variables\n"
3710  	"showvar name ...\n"
3711  	"    - print value of hushshell variable 'name'"
3712  );
3713  
3714  #endif
3715  /****************************************************************************/
3716