common/hush.c

   1 /*
   2  * sh.c -- a prototype Bourne shell grammar parser
   3  *      Intended to follow the original Thompson and Ritchie
   4  *      "small and simple is beautiful" philosophy, which
   5  *      incidentally is a good match to today's BusyBox.
   6  *
   7  * Copyright (C) 2000,2001  Larry Doolittle  <larry@doolittle.boa.org>
   8  *
   9  * Credits:
  10  *      The parser routines proper are all original material, first
  11  *      written Dec 2000 and Jan 2001 by Larry Doolittle.
  12  *      The execution engine, the builtins, and much of the underlying
  13  *      support has been adapted from busybox-0.49pre's lash,
  14  *      which is Copyright (C) 2000 by Lineo, Inc., and
  15  *      written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>.
  16  *      That, in turn, is based in part on ladsh.c, by Michael K. Johnson and
  17  *      Erik W. Troan, which they placed in the public domain.  I don't know
  18  *      how much of the Johnson/Troan code has survived the repeated rewrites.
  19  * Other credits:
  20  *      simple_itoa() was lifted from boa-0.93.15
  21  *      b_addchr() derived from similar w_addchar function in glibc-2.2
  22  *      setup_redirect(), redirect_opt_num(), and big chunks of main()
  23  *        and many builtins derived from contributions by Erik Andersen
  24  *      miscellaneous bugfixes from Matt Kraai
  25  *
  26  * There are two big (and related) architecture differences between
  27  * this parser and the lash parser.  One is that this version is
  28  * actually designed from the ground up to understand nearly all
  29  * of the Bourne grammar.  The second, consequential change is that
  30  * the parser and input reader have been turned inside out.  Now,
  31  * the parser is in control, and asks for input as needed.  The old
  32  * way had the input reader in control, and it asked for parsing to
  33  * take place as needed.  The new way makes it much easier to properly
  34  * handle the recursion implicit in the various substitutions, especially
  35  * across continuation lines.
  36  *
  37  * Bash grammar not implemented: (how many of these were in original sh?)
  38  *      $@ (those sure look like weird quoting rules)
  39  *      $_
  40  *      ! negation operator for pipes
  41  *      &> and >& redirection of stdout+stderr
  42  *      Brace Expansion
  43  *      Tilde Expansion
  44  *      fancy forms of Parameter Expansion
  45  *      aliases
  46  *      Arithmetic Expansion
  47  *      <(list) and >(list) Process Substitution
  48  *      reserved words: case, esac, select, function
  49  *      Here Documents ( << word )
  50  *      Functions
  51  * Major bugs:
  52  *      job handling woefully incomplete and buggy
  53  *      reserved word execution woefully incomplete and buggy
  54  * to-do:
  55  *      port selected bugfixes from post-0.49 busybox lash - done?
  56  *      finish implementing reserved words: for, while, until, do, done
  57  *      change { and } from special chars to reserved words
  58  *      builtins: break, continue, eval, return, set, trap, ulimit
  59  *      test magic exec
  60  *      handle children going into background
  61  *      clean up recognition of null pipes
  62  *      check setting of global_argc and global_argv
  63  *      control-C handling, probably with longjmp
  64  *      follow IFS rules more precisely, including update semantics
  65  *      figure out what to do with backslash-newline
  66  *      explain why we use signal instead of sigaction
  67  *      propagate syntax errors, die on resource errors?
  68  *      continuation lines, both explicit and implicit - done?
  69  *      memory leak finding and plugging - done?
  70  *      more testing, especially quoting rules and redirection
  71  *      document how quoting rules not precisely followed for variable assignments
  72  *      maybe change map[] to use 2-bit entries
  73  *      (eventually) remove all the printf's
  74  *
  75  * This program is free software; you can redistribute it and/or modify
  76  * it under the terms of the GNU General Public License as published by
  77  * the Free Software Foundation; either version 2 of the License, or
  78  * (at your option) any later version.
  79  *
  80  * This program is distributed in the hope that it will be useful,
  81  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  82  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  83  * General Public License for more details.
  84  *
  85  * You should have received a copy of the GNU General Public License
  86  * along with this program; if not, write to the Free Software
  87  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  88  */
  89 #define __U_BOOT__
  90 #ifdef __U_BOOT__
  91 #include <malloc.h>         /* malloc, free, realloc*/
  92 #include <linux/ctype.h>    /* isalpha, isdigit */
  93 #include <common.h>        /* readline */
  94 #include <hush.h>
  95 #include <command.h>        /* find_cmd */
  96 #endif
  97 #ifndef __U_BOOT__
  98 #include <ctype.h>     /* isalpha, isdigit */
  99 #include <unistd.h>    /* getpid */
 100 #include <stdlib.h>    /* getenv, atoi */
 101 #include <string.h>    /* strchr */
 102 #include <stdio.h>     /* popen etc. */
 103 #include <glob.h>      /* glob, of course */
 104 #include <stdarg.h>    /* va_list */
 105 #include <errno.h>
 106 #include <fcntl.h>
 107 #include <getopt.h>    /* should be pretty obvious */
 108
 109 #include <sys/stat.h>  /* ulimit */
 110 #include <sys/types.h>
 111 #include <sys/wait.h>
 112 #include <signal.h>
 113
 114 /* #include <dmalloc.h> */
 115
 116 #if 1
 117 #include "busybox.h"
 118 #include "cmdedit.h"
 119 #else
 120 #define applet_name "hush"
 121 #include "standalone.h"
 122 #define hush_main main
 123 #undef CONFIG_FEATURE_SH_FANCY_PROMPT
 124 #define BB_BANNER
 125 #endif
 126 #endif
 127 #define SPECIAL_VAR_SYMBOL 03
 128 #ifndef __U_BOOT__
 129 #define FLAG_EXIT_FROM_LOOP 1
 130 #define FLAG_PARSE_SEMICOLON (1 << 1)           /* symbol ';' is special for parser */
 131 #define FLAG_REPARSING       (1 << 2)           /* >= 2nd pass */
 132
 133 #endif
 134
 135 #ifdef __U_BOOT__
 136 DECLARE_GLOBAL_DATA_PTR;
 137
 138 #define EXIT_SUCCESS 0
 139 #define EOF -1
 140 #define syntax() syntax_err()
 141 #define xstrdup strdup
 142 #define error_msg printf
 143 #else
 144 typedef enum {
 145         REDIRECT_INPUT     = 1,
 146         REDIRECT_OVERWRITE = 2,
 147         REDIRECT_APPEND    = 3,
 148         REDIRECT_HEREIS    = 4,
 149         REDIRECT_IO        = 5
 150 } redir_type;
 151
 152 /* The descrip member of this structure is only used to make debugging
 153  * output pretty */
 154 struct {int mode; int default_fd; char *descrip;} redir_table[] = {
 155         { 0,                         0, "()" },
 156         { O_RDONLY,                  0, "<"  },
 157         { O_CREAT|O_TRUNC|O_WRONLY,  1, ">"  },
 158         { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
 159         { O_RDONLY,                 -1, "<<" },
 160         { O_RDWR,                    1, "<>" }
 161 };
 162 #endif
 163
 164 typedef enum {
 165         PIPE_SEQ = 1,
 166         PIPE_AND = 2,
 167         PIPE_OR  = 3,
 168         PIPE_BG  = 4,
 169 } pipe_style;
 170
 171 /* might eventually control execution */
 172 typedef enum {
 173         RES_NONE  = 0,
 174         RES_IF    = 1,
 175         RES_THEN  = 2,
 176         RES_ELIF  = 3,
 177         RES_ELSE  = 4,
 178         RES_FI    = 5,
 179         RES_FOR   = 6,
 180         RES_WHILE = 7,
 181         RES_UNTIL = 8,
 182         RES_DO    = 9,
 183         RES_DONE  = 10,
 184         RES_XXXX  = 11,
 185         RES_IN    = 12,
 186         RES_SNTX  = 13
 187 } reserved_style;
 188 #define FLAG_END   (1<<RES_NONE)
 189 #define FLAG_IF    (1<<RES_IF)
 190 #define FLAG_THEN  (1<<RES_THEN)
 191 #define FLAG_ELIF  (1<<RES_ELIF)
 192 #define FLAG_ELSE  (1<<RES_ELSE)
 193 #define FLAG_FI    (1<<RES_FI)
 194 #define FLAG_FOR   (1<<RES_FOR)
 195 #define FLAG_WHILE (1<<RES_WHILE)
 196 #define FLAG_UNTIL (1<<RES_UNTIL)
 197 #define FLAG_DO    (1<<RES_DO)
 198 #define FLAG_DONE  (1<<RES_DONE)
 199 #define FLAG_IN    (1<<RES_IN)
 200 #define FLAG_START (1<<RES_XXXX)
 201
 202 /* This holds pointers to the various results of parsing */
 203 struct p_context {
 204         struct child_prog *child;
 205         struct pipe *list_head;
 206         struct pipe *pipe;
 207 #ifndef __U_BOOT__
 208         struct redir_struct *pending_redirect;
 209 #endif
 210         reserved_style w;
 211         int old_flag;                           /* for figuring out valid reserved words */
 212         struct p_context *stack;
 213         int type;                       /* define type of parser : ";$" common or special symbol */
 214         /* How about quoting status? */
 215 };
 216
 217 #ifndef __U_BOOT__
 218 struct redir_struct {
 219         redir_type type;                        /* type of redirection */
 220         int fd;                                         /* file descriptor being redirected */
 221         int dup;                                        /* -1, or file descriptor being duplicated */
 222         struct redir_struct *next;      /* pointer to the next redirect in the list */
 223         glob_t word;                            /* *word.gl_pathv is the filename */
 224 };
 225 #endif
 226
 227 struct child_prog {
 228 #ifndef __U_BOOT__
 229         pid_t pid;                                      /* 0 if exited */
 230 #endif
 231         char **argv;                            /* program name and arguments */
 232 #ifdef __U_BOOT__
 233         int    argc;                            /* number of program arguments */
 234 #endif
 235         struct pipe *group;                     /* if non-NULL, first in group or subshell */
 236 #ifndef __U_BOOT__
 237         int subshell;                           /* flag, non-zero if group must be forked */
 238         struct redir_struct *redirects; /* I/O redirections */
 239         glob_t glob_result;                     /* result of parameter globbing */
 240         int is_stopped;                         /* is the program currently running? */
 241         struct pipe *family;            /* pointer back to the child's parent pipe */
 242 #endif
 243         int sp;                         /* number of SPECIAL_VAR_SYMBOL */
 244         int type;
 245 };
 246
 247 struct pipe {
 248 #ifndef __U_BOOT__
 249         int jobid;                                      /* job number */
 250 #endif
 251         int num_progs;                          /* total number of programs in job */
 252 #ifndef __U_BOOT__
 253         int running_progs;                      /* number of programs running */
 254         char *text;                                     /* name of job */
 255         char *cmdbuf;                           /* buffer various argv's point into */
 256         pid_t pgrp;                                     /* process group ID for the job */
 257 #endif
 258         struct child_prog *progs;       /* array of commands in pipe */
 259         struct pipe *next;                      /* to track background commands */
 260 #ifndef __U_BOOT__
 261         int stopped_progs;                      /* number of programs alive, but stopped */
 262         int job_context;                        /* bitmask defining current context */
 263 #endif
 264         pipe_style followup;            /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
 265         reserved_style r_mode;          /* supports if, for, while, until */
 266 };
 267
 268 #ifndef __U_BOOT__
 269 struct close_me {
 270         int fd;
 271         struct close_me *next;
 272 };
 273 #endif
 274
 275 struct variables {
 276         char *name;
 277         char *value;
 278         int flg_export;
 279         int flg_read_only;
 280         struct variables *next;
 281 };
 282
 283 /* globals, connect us to the outside world
 284  * the first three support $?, $#, and $1 */
 285 #ifndef __U_BOOT__
 286 char **global_argv;
 287 unsigned int global_argc;
 288 #endif
 289 unsigned int last_return_code;
 290 int nesting_level;
 291 #ifndef __U_BOOT__
 292 extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
 293 #endif
 294
 295 /* "globals" within this file */
 296 static uchar *ifs;
 297 static char map[256];
 298 #ifndef __U_BOOT__
 299 static int fake_mode;
 300 static int interactive;
 301 static struct close_me *close_me_head;
 302 static const char *cwd;
 303 static struct pipe *job_list;
 304 static unsigned int last_bg_pid;
 305 static unsigned int last_jobid;
 306 static unsigned int shell_terminal;
 307 static char *PS1;
 308 static char *PS2;
 309 struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
 310 struct variables *top_vars = &shell_ver;
 311 #else
 312 static int flag_repeat = 0;
 313 static int do_repeat = 0;
 314 static struct variables *top_vars = NULL ;
 315 #endif /*__U_BOOT__ */
 316
 317 #define B_CHUNK (100)
 318 #define B_NOSPAC 1
 319
 320 typedef struct {
 321         char *data;
 322         int length;
 323         int maxlen;
 324         int quote;
 325         int nonnull;
 326 } o_string;
 327 #define NULL_O_STRING {NULL,0,0,0,0}
 328 /* used for initialization:
 329         o_string foo = NULL_O_STRING; */
 330
 331 /* I can almost use ordinary FILE *.  Is open_memstream() universally
 332  * available?  Where is it documented? */
 333 struct in_str {
 334         const char *p;
 335 #ifndef __U_BOOT__
 336         char peek_buf[2];
 337 #endif
 338         int __promptme;
 339         int promptmode;
 340 #ifndef __U_BOOT__
 341         FILE *file;
 342 #endif
 343         int (*get) (struct in_str *);
 344         int (*peek) (struct in_str *);
 345 };
 346 #define b_getch(input) ((input)->get(input))
 347 #define b_peek(input) ((input)->peek(input))
 348
 349 #ifndef __U_BOOT__
 350 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
 351
 352 struct built_in_command {
 353         char *cmd;                                      /* name */
 354         char *descr;                            /* description */
 355         int (*function) (struct child_prog *);  /* function ptr */
 356 };
 357 #endif
 358
 359 /* define DEBUG_SHELL for debugging output (obviously ;-)) */
 360 #if 0
 361 #define DEBUG_SHELL
 362 #endif
 363
 364 /* This should be in utility.c */
 365 #ifdef DEBUG_SHELL
 366 #ifndef __U_BOOT__
 367 static void debug_printf(const char *format, ...)
 368 {
 369         va_list args;
 370         va_start(args, format);
 371         vfprintf(stderr, format, args);
 372         va_end(args);
 373 }
 374 #else
 375 #define debug_printf(fmt,args...)       printf (fmt ,##args)
 376 #endif
 377 #else
 378 static inline void debug_printf(const char *format, ...) { }
 379 #endif
 380 #define final_printf debug_printf
 381
 382 #ifdef __U_BOOT__
 383 static void syntax_err(void) {
 384          printf("syntax error\n");
 385 }
 386 #else
 387 static void __syntax(char *file, int line) {
 388         error_msg("syntax error %s:%d", file, line);
 389 }
 390 #define syntax() __syntax(__FILE__, __LINE__)
 391 #endif
 392
 393 #ifdef __U_BOOT__
 394 static void *xmalloc(size_t size);
 395 static void *xrealloc(void *ptr, size_t size);
 396 #else
 397 /* Index of subroutines: */
 398 /*   function prototypes for builtins */
 399 static int builtin_cd(struct child_prog *child);
 400 static int builtin_env(struct child_prog *child);
 401 static int builtin_eval(struct child_prog *child);
 402 static int builtin_exec(struct child_prog *child);
 403 static int builtin_exit(struct child_prog *child);
 404 static int builtin_export(struct child_prog *child);
 405 static int builtin_fg_bg(struct child_prog *child);
 406 static int builtin_help(struct child_prog *child);
 407 static int builtin_jobs(struct child_prog *child);
 408 static int builtin_pwd(struct child_prog *child);
 409 static int builtin_read(struct child_prog *child);
 410 static int builtin_set(struct child_prog *child);
 411 static int builtin_shift(struct child_prog *child);
 412 static int builtin_source(struct child_prog *child);
 413 static int builtin_umask(struct child_prog *child);
 414 static int builtin_unset(struct child_prog *child);
 415 static int builtin_not_written(struct child_prog *child);
 416 #endif
 417 /*   o_string manipulation: */
 418 static int b_check_space(o_string *o, int len);
 419 static int b_addchr(o_string *o, int ch);
 420 static void b_reset(o_string *o);
 421 static int b_addqchr(o_string *o, int ch, int quote);
 422 #ifndef __U_BOOT__
 423 static int b_adduint(o_string *o, unsigned int i);
 424 #endif
 425 /*  in_str manipulations: */
 426 static int static_get(struct in_str *i);
 427 static int static_peek(struct in_str *i);
 428 static int file_get(struct in_str *i);
 429 static int file_peek(struct in_str *i);
 430 #ifndef __U_BOOT__
 431 static void setup_file_in_str(struct in_str *i, FILE *f);
 432 #else
 433 static void setup_file_in_str(struct in_str *i);
 434 #endif
 435 static void setup_string_in_str(struct in_str *i, const char *s);
 436 #ifndef __U_BOOT__
 437 /*  close_me manipulations: */
 438 static void mark_open(int fd);
 439 static void mark_closed(int fd);
 440 static void close_all(void);
 441 #endif
 442 /*  "run" the final data structures: */
 443 static char *indenter(int i);
 444 static int free_pipe_list(struct pipe *head, int indent);
 445 static int free_pipe(struct pipe *pi, int indent);
 446 /*  really run the final data structures: */
 447 #ifndef __U_BOOT__
 448 static int setup_redirects(struct child_prog *prog, int squirrel[]);
 449 #endif
 450 static int run_list_real(struct pipe *pi);
 451 #ifndef __U_BOOT__
 452 static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
 453 #endif
 454 static int run_pipe_real(struct pipe *pi);
 455 /*   extended glob support: */
 456 #ifndef __U_BOOT__
 457 static int globhack(const char *src, int flags, glob_t *pglob);
 458 static int glob_needed(const char *s);
 459 static int xglob(o_string *dest, int flags, glob_t *pglob);
 460 #endif
 461 /*   variable assignment: */
 462 static int is_assignment(const char *s);
 463 /*   data structure manipulation: */
 464 #ifndef __U_BOOT__
 465 static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
 466 #endif
 467 static void initialize_context(struct p_context *ctx);
 468 static int done_word(o_string *dest, struct p_context *ctx);
 469 static int done_command(struct p_context *ctx);
 470 static int done_pipe(struct p_context *ctx, pipe_style type);
 471 /*   primary string parsing: */
 472 #ifndef __U_BOOT__
 473 static int redirect_dup_num(struct in_str *input);
 474 static int redirect_opt_num(o_string *o);
 475 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
 476 static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
 477 #endif
 478 static char *lookup_param(char *src);
 479 static char *make_string(char **inp);
 480 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
 481 #ifndef __U_BOOT__
 482 static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
 483 #endif
 484 static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
 485 /*   setup: */
 486 static int parse_stream_outer(struct in_str *inp, int flag);
 487 #ifndef __U_BOOT__
 488 static int parse_string_outer(const char *s, int flag);
 489 static int parse_file_outer(FILE *f);
 490 #endif
 491 #ifndef __U_BOOT__
 492 /*   job management: */
 493 static int checkjobs(struct pipe* fg_pipe);
 494 static void insert_bg_job(struct pipe *pi);
 495 static void remove_bg_job(struct pipe *pi);
 496 #endif
 497 /*     local variable support */
 498 static char **make_list_in(char **inp, char *name);
 499 static char *insert_var_value(char *inp);
 500 static char *get_local_var(const char *var);
 501
 502 #ifndef __U_BOOT__
 503 /* Table of built-in functions.  They can be forked or not, depending on
 504  * context: within pipes, they fork.  As simple commands, they do not.
 505  * When used in non-forking context, they can change global variables
 506  * in the parent shell process.  If forked, of course they can not.
 507  * For example, 'unset foo | whatever' will parse and run, but foo will
 508  * still be set at the end. */
 509 static struct built_in_command bltins[] = {
 510         {"bg", "Resume a job in the background", builtin_fg_bg},
 511         {"break", "Exit for, while or until loop", builtin_not_written},
 512         {"cd", "Change working directory", builtin_cd},
 513         {"continue", "Continue for, while or until loop", builtin_not_written},
 514         {"env", "Print all environment variables", builtin_env},
 515         {"eval", "Construct and run shell command", builtin_eval},
 516         {"exec", "Exec command, replacing this shell with the exec'd process",
 517                 builtin_exec},
 518         {"exit", "Exit from shell()", builtin_exit},
 519         {"export", "Set environment variable", builtin_export},
 520         {"fg", "Bring job into the foreground", builtin_fg_bg},
 521         {"jobs", "Lists the active jobs", builtin_jobs},
 522         {"pwd", "Print current directory", builtin_pwd},
 523         {"read", "Input environment variable", builtin_read},
 524         {"return", "Return from a function", builtin_not_written},
 525         {"set", "Set/unset shell local variables", builtin_set},
 526         {"shift", "Shift positional parameters", builtin_shift},
 527         {"trap", "Trap signals", builtin_not_written},
 528         {"ulimit","Controls resource limits", builtin_not_written},
 529         {"umask","Sets file creation mask", builtin_umask},
 530         {"unset", "Unset environment variable", builtin_unset},
 531         {".", "Source-in and run commands in a file", builtin_source},
 532         {"help", "List shell built-in commands", builtin_help},
 533         {NULL, NULL, NULL}
 534 };
 535
 536 static const char *set_cwd(void)
 537 {
 538         if(cwd==unknown)
 539                 cwd = NULL;     /* xgetcwd(arg) called free(arg) */
 540         cwd = xgetcwd((char *)cwd);
 541         if (!cwd)
 542                 cwd = unknown;
 543         return cwd;
 544 }
 545
 546 /* built-in 'eval' handler */
 547 static int builtin_eval(struct child_prog *child)
 548 {
 549         char *str = NULL;
 550         int rcode = EXIT_SUCCESS;
 551
 552         if (child->argv[1]) {
 553                 str = make_string(child->argv + 1);
 554                 parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
 555                                         FLAG_PARSE_SEMICOLON);
 556                 free(str);
 557                 rcode = last_return_code;
 558         }
 559         return rcode;
 560 }
 561
 562 /* built-in 'cd <path>' handler */
 563 static int builtin_cd(struct child_prog *child)
 564 {
 565         char *newdir;
 566         if (child->argv[1] == NULL)
 567                 newdir = getenv("HOME");
 568         else
 569                 newdir = child->argv[1];
 570         if (chdir(newdir)) {
 571                 printf("cd: %s: %s\n", newdir, strerror(errno));
 572                 return EXIT_FAILURE;
 573         }
 574         set_cwd();
 575         return EXIT_SUCCESS;
 576 }
 577
 578 /* built-in 'env' handler */
 579 static int builtin_env(struct child_prog *dummy)
 580 {
 581         char **e = environ;
 582         if (e == NULL) return EXIT_FAILURE;
 583         for (; *e; e++) {
 584                 puts(*e);
 585         }
 586         return EXIT_SUCCESS;
 587 }
 588
 589 /* built-in 'exec' handler */
 590 static int builtin_exec(struct child_prog *child)
 591 {
 592         if (child->argv[1] == NULL)
 593                 return EXIT_SUCCESS;   /* Really? */
 594         child->argv++;
 595         pseudo_exec(child);
 596         /* never returns */
 597 }
 598
 599 /* built-in 'exit' handler */
 600 static int builtin_exit(struct child_prog *child)
 601 {
 602         if (child->argv[1] == NULL)
 603                 exit(last_return_code);
 604         exit (atoi(child->argv[1]));
 605 }
 606
 607 /* built-in 'export VAR=value' handler */
 608 static int builtin_export(struct child_prog *child)
 609 {
 610         int res = 0;
 611         char *name = child->argv[1];
 612
 613         if (name == NULL) {
 614                 return (builtin_env(child));
 615         }
 616
 617         name = strdup(name);
 618
 619         if(name) {
 620                 char *value = strchr(name, '=');
 621
 622                 if (!value) {
 623                         char *tmp;
 624                         /* They are exporting something without an =VALUE */
 625
 626                         value = get_local_var(name);
 627                         if (value) {
 628                                 size_t ln = strlen(name);
 629
 630                                 tmp = realloc(name, ln+strlen(value)+2);
 631                                 if(tmp==NULL)
 632                                         res = -1;
 633                                 else {
 634                                         sprintf(tmp+ln, "=%s", value);
 635                                         name = tmp;
 636                                 }
 637                         } else {
 638                                 /* bash does not return an error when trying to export
 639                                  * an undefined variable.  Do likewise. */
 640                                 res = 1;
 641                         }
 642                 }
 643         }
 644         if (res<0)
 645                 perror_msg("export");
 646         else if(res==0)
 647                 res = set_local_var(name, 1);
 648         else
 649                 res = 0;
 650         free(name);
 651         return res;
 652 }
 653
 654 /* built-in 'fg' and 'bg' handler */
 655 static int builtin_fg_bg(struct child_prog *child)
 656 {
 657         int i, jobnum;
 658         struct pipe *pi=NULL;
 659
 660         if (!interactive)
 661                 return EXIT_FAILURE;
 662         /* If they gave us no args, assume they want the last backgrounded task */
 663         if (!child->argv[1]) {
 664                 for (pi = job_list; pi; pi = pi->next) {
 665                         if (pi->jobid == last_jobid) {
 666                                 break;
 667                         }
 668                 }
 669                 if (!pi) {
 670                         error_msg("%s: no current job", child->argv[0]);
 671                         return EXIT_FAILURE;
 672                 }
 673         } else {
 674                 if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
 675                         error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
 676                         return EXIT_FAILURE;
 677                 }
 678                 for (pi = job_list; pi; pi = pi->next) {
 679                         if (pi->jobid == jobnum) {
 680                                 break;
 681                         }
 682                 }
 683                 if (!pi) {
 684                         error_msg("%s: %d: no such job", child->argv[0], jobnum);
 685                         return EXIT_FAILURE;
 686                 }
 687         }
 688
 689         if (*child->argv[0] == 'f') {
 690                 /* Put the job into the foreground.  */
 691                 tcsetpgrp(shell_terminal, pi->pgrp);
 692         }
 693
 694         /* Restart the processes in the job */
 695         for (i = 0; i < pi->num_progs; i++)
 696                 pi->progs[i].is_stopped = 0;
 697
 698         if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) {
 699                 if (i == ESRCH) {
 700                         remove_bg_job(pi);
 701                 } else {
 702                         perror_msg("kill (SIGCONT)");
 703                 }
 704         }
 705
 706         pi->stopped_progs = 0;
 707         return EXIT_SUCCESS;
 708 }
 709
 710 /* built-in 'help' handler */
 711 static int builtin_help(struct child_prog *dummy)
 712 {
 713         struct built_in_command *x;
 714
 715         printf("\nBuilt-in commands:\n");
 716         printf("-------------------\n");
 717         for (x = bltins; x->cmd; x++) {
 718                 if (x->descr==NULL)
 719                         continue;
 720                 printf("%s\t%s\n", x->cmd, x->descr);
 721         }
 722         printf("\n\n");
 723         return EXIT_SUCCESS;
 724 }
 725
 726 /* built-in 'jobs' handler */
 727 static int builtin_jobs(struct child_prog *child)
 728 {
 729         struct pipe *job;
 730         char *status_string;
 731
 732         for (job = job_list; job; job = job->next) {
 733                 if (job->running_progs == job->stopped_progs)
 734                         status_string = "Stopped";
 735                 else
 736                         status_string = "Running";
 737
 738                 printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
 739         }
 740         return EXIT_SUCCESS;
 741 }
 742
 743
 744 /* built-in 'pwd' handler */
 745 static int builtin_pwd(struct child_prog *dummy)
 746 {
 747         puts(set_cwd());
 748         return EXIT_SUCCESS;
 749 }
 750
 751 /* built-in 'read VAR' handler */
 752 static int builtin_read(struct child_prog *child)
 753 {
 754         int res;
 755
 756         if (child->argv[1]) {
 757                 char string[BUFSIZ];
 758                 char *var = 0;
 759
 760                 string[0] = 0;  /* In case stdin has only EOF */
 761                 /* read string */
 762                 fgets(string, sizeof(string), stdin);
 763                 chomp(string);
 764                 var = malloc(strlen(child->argv[1])+strlen(string)+2);
 765                 if(var) {
 766                         sprintf(var, "%s=%s", child->argv[1], string);
 767                         res = set_local_var(var, 0);
 768                 } else
 769                         res = -1;
 770                 if (res)
 771                         fprintf(stderr, "read: %m\n");
 772                 free(var);      /* So not move up to avoid breaking errno */
 773                 return res;
 774         } else {
 775                 do res=getchar(); while(res!='\n' && res!=EOF);
 776                 return 0;
 777         }
 778 }
 779
 780 /* built-in 'set VAR=value' handler */
 781 static int builtin_set(struct child_prog *child)
 782 {
 783         char *temp = child->argv[1];
 784         struct variables *e;
 785
 786         if (temp == NULL)
 787                 for(e = top_vars; e; e=e->next)
 788                         printf("%s=%s\n", e->name, e->value);
 789         else
 790                 set_local_var(temp, 0);
 791
 792                 return EXIT_SUCCESS;
 793 }
 794
 795
 796 /* Built-in 'shift' handler */
 797 static int builtin_shift(struct child_prog *child)
 798 {
 799         int n=1;
 800         if (child->argv[1]) {
 801                 n=atoi(child->argv[1]);
 802         }
 803         if (n>=0 && n<global_argc) {
 804                 /* XXX This probably breaks $0 */
 805                 global_argc -= n;
 806                 global_argv += n;
 807                 return EXIT_SUCCESS;
 808         } else {
 809                 return EXIT_FAILURE;
 810         }
 811 }
 812
 813 /* Built-in '.' handler (read-in and execute commands from file) */
 814 static int builtin_source(struct child_prog *child)
 815 {
 816         FILE *input;
 817         int status;
 818
 819         if (child->argv[1] == NULL)
 820                 return EXIT_FAILURE;
 821
 822         /* XXX search through $PATH is missing */
 823         input = fopen(child->argv[1], "r");
 824         if (!input) {
 825                 error_msg("Couldn't open file '%s'", child->argv[1]);
 826                 return EXIT_FAILURE;
 827         }
 828
 829         /* Now run the file */
 830         /* XXX argv and argc are broken; need to save old global_argv
 831          * (pointer only is OK!) on this stack frame,
 832          * set global_argv=child->argv+1, recurse, and restore. */
 833         mark_open(fileno(input));
 834         status = parse_file_outer(input);
 835         mark_closed(fileno(input));
 836         fclose(input);
 837         return (status);
 838 }
 839
 840 static int builtin_umask(struct child_prog *child)
 841 {
 842         mode_t new_umask;
 843         const char *arg = child->argv[1];
 844         char *end;
 845         if (arg) {
 846                 new_umask=strtoul(arg, &end, 8);
 847                 if (*end!='\0' || end == arg) {
 848                         return EXIT_FAILURE;
 849                 }
 850         } else {
 851                 printf("%.3o\n", (unsigned int) (new_umask=umask(0)));
 852         }
 853         umask(new_umask);
 854         return EXIT_SUCCESS;
 855 }
 856
 857 /* built-in 'unset VAR' handler */
 858 static int builtin_unset(struct child_prog *child)
 859 {
 860         /* bash returned already true */
 861         unset_local_var(child->argv[1]);
 862         return EXIT_SUCCESS;
 863 }
 864
 865 static int builtin_not_written(struct child_prog *child)
 866 {
 867         printf("builtin_%s not written\n",child->argv[0]);
 868         return EXIT_FAILURE;
 869 }
 870 #endif
 871
 872 static int b_check_space(o_string *o, int len)
 873 {
 874         /* It would be easy to drop a more restrictive policy
 875          * in here, such as setting a maximum string length */
 876         if (o->length + len > o->maxlen) {
 877                 char *old_data = o->data;
 878                 /* assert (data == NULL || o->maxlen != 0); */
 879                 o->maxlen += max(2*len, B_CHUNK);
 880                 o->data = realloc(o->data, 1 + o->maxlen);
 881                 if (o->data == NULL) {
 882                         free(old_data);
 883                 }
 884         }
 885         return o->data == NULL;
 886 }
 887
 888 static int b_addchr(o_string *o, int ch)
 889 {
 890         debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
 891         if (b_check_space(o, 1)) return B_NOSPAC;
 892         o->data[o->length] = ch;
 893         o->length++;
 894         o->data[o->length] = '\0';
 895         return 0;
 896 }
 897
 898 static void b_reset(o_string *o)
 899 {
 900         o->length = 0;
 901         o->nonnull = 0;
 902         if (o->data != NULL) *o->data = '\0';
 903 }
 904
 905 static void b_free(o_string *o)
 906 {
 907         b_reset(o);
 908         free(o->data);
 909         o->data = NULL;
 910         o->maxlen = 0;
 911 }
 912
 913 /* My analysis of quoting semantics tells me that state information
 914  * is associated with a destination, not a source.
 915  */
 916 static int b_addqchr(o_string *o, int ch, int quote)
 917 {
 918         if (quote && strchr("*?[\\",ch)) {
 919                 int rc;
 920                 rc = b_addchr(o, '\\');
 921                 if (rc) return rc;
 922         }
 923         return b_addchr(o, ch);
 924 }
 925
 926 /* belongs in utility.c */
 927 char *simple_itoa(unsigned int i)
 928 {
 929         /* 21 digits plus null terminator, good for 64-bit or smaller ints */
 930         static char local[22];
 931         char *p = &local[21];
 932         *p-- = '\0';
 933         do {
 934                 *p-- = '0' + i % 10;
 935                 i /= 10;
 936         } while (i > 0);
 937         return p + 1;
 938 }
 939
 940 #ifndef __U_BOOT__
 941 static int b_adduint(o_string *o, unsigned int i)
 942 {
 943         int r;
 944         char *p = simple_itoa(i);
 945         /* no escape checking necessary */
 946         do r=b_addchr(o, *p++); while (r==0 && *p);
 947         return r;
 948 }
 949 #endif
 950
 951 static int static_get(struct in_str *i)
 952 {
 953         int ch = *i->p++;
 954         if (ch=='\0') return EOF;
 955         return ch;
 956 }
 957
 958 static int static_peek(struct in_str *i)
 959 {
 960         return *i->p;
 961 }
 962
 963 #ifndef __U_BOOT__
 964 static inline void cmdedit_set_initial_prompt(void)
 965 {
 966 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
 967         PS1 = NULL;
 968 #else
 969         PS1 = getenv("PS1");
 970         if(PS1==0)
 971                 PS1 = "\\w \\$ ";
 972 #endif
 973 }
 974
 975 static inline void setup_prompt_string(int promptmode, char **prompt_str)
 976 {
 977         debug_printf("setup_prompt_string %d ",promptmode);
 978 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
 979         /* Set up the prompt */
 980         if (promptmode == 1) {
 981                 free(PS1);
 982                 PS1=xmalloc(strlen(cwd)+4);
 983                 sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ?  "$ ":"# ");
 984                 *prompt_str = PS1;
 985         } else {
 986                 *prompt_str = PS2;
 987         }
 988 #else
 989         *prompt_str = (promptmode==1)? PS1 : PS2;
 990 #endif
 991         debug_printf("result %s\n",*prompt_str);
 992 }
 993 #endif
 994
 995 static void get_user_input(struct in_str *i)
 996 {
 997 #ifndef __U_BOOT__
 998         char *prompt_str;
 999         static char the_command[BUFSIZ];
1000
1001         setup_prompt_string(i->promptmode, &prompt_str);
1002 #ifdef CONFIG_FEATURE_COMMAND_EDITING
1003         /*
1004          ** enable command line editing only while a command line
1005          ** is actually being read; otherwise, we'll end up bequeathing
1006          ** atexit() handlers and other unwanted stuff to our
1007          ** child processes (rob@sysgo.de)
1008          */
1009         cmdedit_read_input(prompt_str, the_command);
1010 #else
1011         fputs(prompt_str, stdout);
1012         fflush(stdout);
1013         the_command[0]=fgetc(i->file);
1014         the_command[1]='\0';
1015 #endif
1016         fflush(stdout);
1017         i->p = the_command;
1018 #else
1019         extern char console_buffer[];
1020         int n;
1021         static char the_command[CONFIG_SYS_CBSIZE];
1022
1023 #ifdef CONFIG_BOOT_RETRY_TIME
1024 #  ifdef CONFIG_RESET_TO_RETRY
1025         extern int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]);
1026 #  else
1027 #       error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1028 #  endif
1029         reset_cmd_timeout();
1030 #endif
1031         i->__promptme = 1;
1032         if (i->promptmode == 1) {
1033                 n = readline(CONFIG_SYS_PROMPT);
1034         } else {
1035                 n = readline(CONFIG_SYS_PROMPT_HUSH_PS2);
1036         }
1037 #ifdef CONFIG_BOOT_RETRY_TIME
1038         if (n == -2) {
1039           puts("\nTimeout waiting for command\n");
1040 #  ifdef CONFIG_RESET_TO_RETRY
1041           do_reset(NULL, 0, 0, NULL);
1042 #  else
1043 #       error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1044 #  endif
1045         }
1046 #endif
1047         if (n == -1 ) {
1048                 flag_repeat = 0;
1049                 i->__promptme = 0;
1050         }
1051         n = strlen(console_buffer);
1052         console_buffer[n] = '\n';
1053         console_buffer[n+1]= '\0';
1054         if (had_ctrlc()) flag_repeat = 0;
1055         clear_ctrlc();
1056         do_repeat = 0;
1057         if (i->promptmode == 1) {
1058                 if (console_buffer[0] == '\n'&& flag_repeat == 0) {
1059                         strcpy(the_command,console_buffer);
1060                 }
1061                 else {
1062                         if (console_buffer[0] != '\n') {
1063                                 strcpy(the_command,console_buffer);
1064                                 flag_repeat = 1;
1065                         }
1066                         else {
1067                                 do_repeat = 1;
1068                         }
1069                 }
1070                 i->p = the_command;
1071         }
1072         else {
1073                 if (console_buffer[0] != '\n') {
1074                         if (strlen(the_command) + strlen(console_buffer)
1075                             < CONFIG_SYS_CBSIZE) {
1076                                 n = strlen(the_command);
1077                                 the_command[n-1] = ' ';
1078                                 strcpy(&the_command[n],console_buffer);
1079                         }
1080                         else {
1081                                 the_command[0] = '\n';
1082                                 the_command[1] = '\0';
1083                                 flag_repeat = 0;
1084                         }
1085                 }
1086                 if (i->__promptme == 0) {
1087                         the_command[0] = '\n';
1088                         the_command[1] = '\0';
1089                 }
1090                 i->p = console_buffer;
1091         }
1092 #endif
1093 }
1094
1095 /* This is the magic location that prints prompts
1096  * and gets data back from the user */
1097 static int file_get(struct in_str *i)
1098 {
1099         int ch;
1100
1101         ch = 0;
1102         /* If there is data waiting, eat it up */
1103         if (i->p && *i->p) {
1104                 ch = *i->p++;
1105         } else {
1106                 /* need to double check i->file because we might be doing something
1107                  * more complicated by now, like sourcing or substituting. */
1108 #ifndef __U_BOOT__
1109                 if (i->__promptme && interactive && i->file == stdin) {
1110                         while(! i->p || (interactive && strlen(i->p)==0) ) {
1111 #else
1112                         while(! i->p  || strlen(i->p)==0 ) {
1113 #endif
1114                                 get_user_input(i);
1115                         }
1116                         i->promptmode=2;
1117 #ifndef __U_BOOT__
1118                         i->__promptme = 0;
1119 #endif
1120                         if (i->p && *i->p) {
1121                                 ch = *i->p++;
1122                         }
1123 #ifndef __U_BOOT__
1124                 } else {
1125                         ch = fgetc(i->file);
1126                 }
1127
1128 #endif
1129                 debug_printf("b_getch: got a %d\n", ch);
1130         }
1131 #ifndef __U_BOOT__
1132         if (ch == '\n') i->__promptme=1;
1133 #endif
1134         return ch;
1135 }
1136
1137 /* All the callers guarantee this routine will never be
1138  * used right after a newline, so prompting is not needed.
1139  */
1140 static int file_peek(struct in_str *i)
1141 {
1142 #ifndef __U_BOOT__
1143         if (i->p && *i->p) {
1144 #endif
1145                 return *i->p;
1146 #ifndef __U_BOOT__
1147         } else {
1148                 i->peek_buf[0] = fgetc(i->file);
1149                 i->peek_buf[1] = '\0';
1150                 i->p = i->peek_buf;
1151                 debug_printf("b_peek: got a %d\n", *i->p);
1152                 return *i->p;
1153         }
1154 #endif
1155 }
1156
1157 #ifndef __U_BOOT__
1158 static void setup_file_in_str(struct in_str *i, FILE *f)
1159 #else
1160 static void setup_file_in_str(struct in_str *i)
1161 #endif
1162 {
1163         i->peek = file_peek;
1164         i->get = file_get;
1165         i->__promptme=1;
1166         i->promptmode=1;
1167 #ifndef __U_BOOT__
1168         i->file = f;
1169 #endif
1170         i->p = NULL;
1171 }
1172
1173 static void setup_string_in_str(struct in_str *i, const char *s)
1174 {
1175         i->peek = static_peek;
1176         i->get = static_get;
1177         i->__promptme=1;
1178         i->promptmode=1;
1179         i->p = s;
1180 }
1181
1182 #ifndef __U_BOOT__
1183 static void mark_open(int fd)
1184 {
1185         struct close_me *new = xmalloc(sizeof(struct close_me));
1186         new->fd = fd;
1187         new->next = close_me_head;
1188         close_me_head = new;
1189 }
1190
1191 static void mark_closed(int fd)
1192 {
1193         struct close_me *tmp;
1194         if (close_me_head == NULL || close_me_head->fd != fd)
1195                 error_msg_and_die("corrupt close_me");
1196         tmp = close_me_head;
1197         close_me_head = close_me_head->next;
1198         free(tmp);
1199 }
1200
1201 static void close_all(void)
1202 {
1203         struct close_me *c;
1204         for (c=close_me_head; c; c=c->next) {
1205                 close(c->fd);
1206         }
1207         close_me_head = NULL;
1208 }
1209
1210 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1211  * and stderr if they are redirected. */
1212 static int setup_redirects(struct child_prog *prog, int squirrel[])
1213 {
1214         int openfd, mode;
1215         struct redir_struct *redir;
1216
1217         for (redir=prog->redirects; redir; redir=redir->next) {
1218                 if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1219                         /* something went wrong in the parse.  Pretend it didn't happen */
1220                         continue;
1221                 }
1222                 if (redir->dup == -1) {
1223                         mode=redir_table[redir->type].mode;
1224                         openfd = open(redir->word.gl_pathv[0], mode, 0666);
1225                         if (openfd < 0) {
1226                         /* this could get lost if stderr has been redirected, but
1227                            bash and ash both lose it as well (though zsh doesn't!) */
1228                                 perror_msg("error opening %s", redir->word.gl_pathv[0]);
1229                                 return 1;
1230                         }
1231                 } else {
1232                         openfd = redir->dup;
1233                 }
1234
1235                 if (openfd != redir->fd) {
1236                         if (squirrel && redir->fd < 3) {
1237                                 squirrel[redir->fd] = dup(redir->fd);
1238                         }
1239                         if (openfd == -3) {
1240                                 close(openfd);
1241                         } else {
1242                                 dup2(openfd, redir->fd);
1243                                 if (redir->dup == -1)
1244                                         close (openfd);
1245                         }
1246                 }
1247         }
1248         return 0;
1249 }
1250
1251 static void restore_redirects(int squirrel[])
1252 {
1253         int i, fd;
1254         for (i=0; i<3; i++) {
1255                 fd = squirrel[i];
1256                 if (fd != -1) {
1257                         /* No error checking.  I sure wouldn't know what
1258                          * to do with an error if I found one! */
1259                         dup2(fd, i);
1260                         close(fd);
1261                 }
1262         }
1263 }
1264
1265 /* never returns */
1266 /* XXX no exit() here.  If you don't exec, use _exit instead.
1267  * The at_exit handlers apparently confuse the calling process,
1268  * in particular stdin handling.  Not sure why? */
1269 static void pseudo_exec(struct child_prog *child)
1270 {
1271         int i, rcode;
1272         char *p;
1273         struct built_in_command *x;
1274         if (child->argv) {
1275                 for (i=0; is_assignment(child->argv[i]); i++) {
1276                         debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
1277                         p = insert_var_value(child->argv[i]);
1278                         putenv(strdup(p));
1279                         if (p != child->argv[i]) free(p);
1280                 }
1281                 child->argv+=i;  /* XXX this hack isn't so horrible, since we are about
1282                                         to exit, and therefore don't need to keep data
1283                                         structures consistent for free() use. */
1284                 /* If a variable is assigned in a forest, and nobody listens,
1285                  * was it ever really set?
1286                  */
1287                 if (child->argv[0] == NULL) {
1288                         _exit(EXIT_SUCCESS);
1289                 }
1290
1291                 /*
1292                  * Check if the command matches any of the builtins.
1293                  * Depending on context, this might be redundant.  But it's
1294                  * easier to waste a few CPU cycles than it is to figure out
1295                  * if this is one of those cases.
1296                  */
1297                 for (x = bltins; x->cmd; x++) {
1298                         if (strcmp(child->argv[0], x->cmd) == 0 ) {
1299                                 debug_printf("builtin exec %s\n", child->argv[0]);
1300                                 rcode = x->function(child);
1301                                 fflush(stdout);
1302                                 _exit(rcode);
1303                         }
1304                 }
1305
1306                 /* Check if the command matches any busybox internal commands
1307                  * ("applets") here.
1308                  * FIXME: This feature is not 100% safe, since
1309                  * BusyBox is not fully reentrant, so we have no guarantee the things
1310                  * from the .bss are still zeroed, or that things from .data are still
1311                  * at their defaults.  We could exec ourself from /proc/self/exe, but I
1312                  * really dislike relying on /proc for things.  We could exec ourself
1313                  * from global_argv[0], but if we are in a chroot, we may not be able
1314                  * to find ourself... */
1315 #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1316                 {
1317                         int argc_l;
1318                         char** argv_l=child->argv;
1319                         char *name = child->argv[0];
1320
1321 #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
1322                         /* Following discussions from November 2000 on the busybox mailing
1323                          * list, the default configuration, (without
1324                          * get_last_path_component()) lets the user force use of an
1325                          * external command by specifying the full (with slashes) filename.
1326                          * If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN then applets
1327                          * _aways_ override external commands, so if you want to run
1328                          * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the
1329                          * filesystem and is _not_ busybox.  Some systems may want this,
1330                          * most do not.  */
1331                         name = get_last_path_component(name);
1332 #endif
1333                         /* Count argc for use in a second... */
1334                         for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
1335                         optind = 1;
1336                         debug_printf("running applet %s\n", name);
1337                         run_applet_by_name(name, argc_l, child->argv);
1338                 }
1339 #endif
1340                 debug_printf("exec of %s\n",child->argv[0]);
1341                 execvp(child->argv[0],child->argv);
1342                 perror_msg("couldn't exec: %s",child->argv[0]);
1343                 _exit(1);
1344         } else if (child->group) {
1345                 debug_printf("runtime nesting to group\n");
1346                 interactive=0;    /* crucial!!!! */
1347                 rcode = run_list_real(child->group);
1348                 /* OK to leak memory by not calling free_pipe_list,
1349                  * since this process is about to exit */
1350                 _exit(rcode);
1351         } else {
1352                 /* Can happen.  See what bash does with ">foo" by itself. */
1353                 debug_printf("trying to pseudo_exec null command\n");
1354                 _exit(EXIT_SUCCESS);
1355         }
1356 }
1357
1358 static void insert_bg_job(struct pipe *pi)
1359 {
1360         struct pipe *thejob;
1361
1362         /* Linear search for the ID of the job to use */
1363         pi->jobid = 1;
1364         for (thejob = job_list; thejob; thejob = thejob->next)
1365                 if (thejob->jobid >= pi->jobid)
1366                         pi->jobid = thejob->jobid + 1;
1367
1368         /* add thejob to the list of running jobs */
1369         if (!job_list) {
1370                 thejob = job_list = xmalloc(sizeof(*thejob));
1371         } else {
1372                 for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
1373                 thejob->next = xmalloc(sizeof(*thejob));
1374                 thejob = thejob->next;
1375         }
1376
1377         /* physically copy the struct job */
1378         memcpy(thejob, pi, sizeof(struct pipe));
1379         thejob->next = NULL;
1380         thejob->running_progs = thejob->num_progs;
1381         thejob->stopped_progs = 0;
1382         thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1383
1384         /*if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) */
1385         {
1386                 char *bar=thejob->text;
1387                 char **foo=pi->progs[0].argv;
1388                 while(foo && *foo) {
1389                         bar += sprintf(bar, "%s ", *foo++);
1390                 }
1391         }
1392
1393         /* we don't wait for background thejobs to return -- append it
1394            to the list of backgrounded thejobs and leave it alone */
1395         printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1396         last_bg_pid = thejob->progs[0].pid;
1397         last_jobid = thejob->jobid;
1398 }
1399
1400 /* remove a backgrounded job */
1401 static void remove_bg_job(struct pipe *pi)
1402 {
1403         struct pipe *prev_pipe;
1404
1405         if (pi == job_list) {
1406                 job_list = pi->next;
1407         } else {
1408                 prev_pipe = job_list;
1409                 while (prev_pipe->next != pi)
1410                         prev_pipe = prev_pipe->next;
1411                 prev_pipe->next = pi->next;
1412         }
1413         if (job_list)
1414                 last_jobid = job_list->jobid;
1415         else
1416                 last_jobid = 0;
1417
1418         pi->stopped_progs = 0;
1419         free_pipe(pi, 0);
1420         free(pi);
1421 }
1422
1423 /* Checks to see if any processes have exited -- if they
1424    have, figure out why and see if a job has completed */
1425 static int checkjobs(struct pipe* fg_pipe)
1426 {
1427         int attributes;
1428         int status;
1429         int prognum = 0;
1430         struct pipe *pi;
1431         pid_t childpid;
1432
1433         attributes = WUNTRACED;
1434         if (fg_pipe==NULL) {
1435                 attributes |= WNOHANG;
1436         }
1437
1438         while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1439                 if (fg_pipe) {
1440                         int i, rcode = 0;
1441                         for (i=0; i < fg_pipe->num_progs; i++) {
1442                                 if (fg_pipe->progs[i].pid == childpid) {
1443                                         if (i==fg_pipe->num_progs-1)
1444                                                 rcode=WEXITSTATUS(status);
1445                                         (fg_pipe->num_progs)--;
1446                                         return(rcode);
1447                                 }
1448                         }
1449                 }
1450
1451                 for (pi = job_list; pi; pi = pi->next) {
1452                         prognum = 0;
1453                         while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1454                                 prognum++;
1455                         }
1456                         if (prognum < pi->num_progs)
1457                                 break;
1458                 }
1459
1460                 if(pi==NULL) {
1461                         debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
1462                         continue;
1463                 }
1464
1465                 if (WIFEXITED(status) || WIFSIGNALED(status)) {
1466                         /* child exited */
1467                         pi->running_progs--;
1468                         pi->progs[prognum].pid = 0;
1469
1470                         if (!pi->running_progs) {
1471                                 printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
1472                                 remove_bg_job(pi);
1473                         }
1474                 } else {
1475                         /* child stopped */
1476                         pi->stopped_progs++;
1477                         pi->progs[prognum].is_stopped = 1;
1478
1479 #if 0
1480                         /* Printing this stuff is a pain, since it tends to
1481                          * overwrite the prompt an inconveinient moments.  So
1482                          * don't do that.  */
1483                         if (pi->stopped_progs == pi->num_progs) {
1484                                 printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
1485                         }
1486 #endif
1487                 }
1488         }
1489
1490         if (childpid == -1 && errno != ECHILD)
1491                 perror_msg("waitpid");
1492
1493         /* move the shell to the foreground */
1494         /*if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) */
1495         /*      perror_msg("tcsetpgrp-2"); */
1496         return -1;
1497 }
1498
1499 /* Figure out our controlling tty, checking in order stderr,
1500  * stdin, and stdout.  If check_pgrp is set, also check that
1501  * we belong to the foreground process group associated with
1502  * that tty.  The value of shell_terminal is needed in order to call
1503  * tcsetpgrp(shell_terminal, ...); */
1504 void controlling_tty(int check_pgrp)
1505 {
1506         pid_t curpgrp;
1507
1508         if ((curpgrp = tcgetpgrp(shell_terminal = 2)) < 0
1509                         && (curpgrp = tcgetpgrp(shell_terminal = 0)) < 0
1510                         && (curpgrp = tcgetpgrp(shell_terminal = 1)) < 0)
1511                 goto shell_terminal_error;
1512
1513         if (check_pgrp && curpgrp != getpgid(0))
1514                 goto shell_terminal_error;
1515
1516         return;
1517
1518 shell_terminal_error:
1519                 shell_terminal = -1;
1520                 return;
1521 }
1522 #endif
1523
1524 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1525  * to finish.  See checkjobs().
1526  *
1527  * return code is normally -1, when the caller has to wait for children
1528  * to finish to determine the exit status of the pipe.  If the pipe
1529  * is a simple builtin command, however, the action is done by the
1530  * time run_pipe_real returns, and the exit code is provided as the
1531  * return value.
1532  *
1533  * The input of the pipe is always stdin, the output is always
1534  * stdout.  The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1535  * because it tries to avoid running the command substitution in
1536  * subshell, when that is in fact necessary.  The subshell process
1537  * now has its stdout directed to the input of the appropriate pipe,
1538  * so this routine is noticeably simpler.
1539  */
1540 static int run_pipe_real(struct pipe *pi)
1541 {
1542         int i;
1543 #ifndef __U_BOOT__
1544         int nextin, nextout;
1545         int pipefds[2];                         /* pipefds[0] is for reading */
1546         struct child_prog *child;
1547         struct built_in_command *x;
1548         char *p;
1549 # if __GNUC__
1550         /* Avoid longjmp clobbering */
1551         (void) &i;
1552         (void) &nextin;
1553         (void) &nextout;
1554         (void) &child;
1555 # endif
1556 #else
1557         int nextin;
1558         int flag = do_repeat ? CMD_FLAG_REPEAT : 0;
1559         struct child_prog *child;
1560         cmd_tbl_t *cmdtp;
1561         char *p;
1562 # if __GNUC__
1563         /* Avoid longjmp clobbering */
1564         (void) &i;
1565         (void) &nextin;
1566         (void) &child;
1567 # endif
1568 #endif  /* __U_BOOT__ */
1569
1570         nextin = 0;
1571 #ifndef __U_BOOT__
1572         pi->pgrp = -1;
1573 #endif
1574
1575         /* Check if this is a simple builtin (not part of a pipe).
1576          * Builtins within pipes have to fork anyway, and are handled in
1577          * pseudo_exec.  "echo foo | read bar" doesn't work on bash, either.
1578          */
1579         if (pi->num_progs == 1) child = & (pi->progs[0]);
1580 #ifndef __U_BOOT__
1581         if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1582                 int squirrel[] = {-1, -1, -1};
1583                 int rcode;
1584                 debug_printf("non-subshell grouping\n");
1585                 setup_redirects(child, squirrel);
1586                 /* XXX could we merge code with following builtin case,
1587                  * by creating a pseudo builtin that calls run_list_real? */
1588                 rcode = run_list_real(child->group);
1589                 restore_redirects(squirrel);
1590 #else
1591                 if (pi->num_progs == 1 && child->group) {
1592                 int rcode;
1593                 debug_printf("non-subshell grouping\n");
1594                 rcode = run_list_real(child->group);
1595 #endif
1596                 return rcode;
1597         } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1598                 for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
1599                 if (i!=0 && child->argv[i]==NULL) {
1600                         /* assignments, but no command: set the local environment */
1601                         for (i=0; child->argv[i]!=NULL; i++) {
1602
1603                                 /* Ok, this case is tricky.  We have to decide if this is a
1604                                  * local variable, or an already exported variable.  If it is
1605                                  * already exported, we have to export the new value.  If it is
1606                                  * not exported, we need only set this as a local variable.
1607                                  * This junk is all to decide whether or not to export this
1608                                  * variable. */
1609                                 int export_me=0;
1610                                 char *name, *value;
1611                                 name = xstrdup(child->argv[i]);
1612                                 debug_printf("Local environment set: %s\n", name);
1613                                 value = strchr(name, '=');
1614                                 if (value)
1615                                         *value=0;
1616 #ifndef __U_BOOT__
1617                                 if ( get_local_var(name)) {
1618                                         export_me=1;
1619                                 }
1620 #endif
1621                                 free(name);
1622                                 p = insert_var_value(child->argv[i]);
1623                                 set_local_var(p, export_me);
1624                                 if (p != child->argv[i]) free(p);
1625                         }
1626                         return EXIT_SUCCESS;   /* don't worry about errors in set_local_var() yet */
1627                 }
1628                 for (i = 0; is_assignment(child->argv[i]); i++) {
1629                         p = insert_var_value(child->argv[i]);
1630 #ifndef __U_BOOT__
1631                         putenv(strdup(p));
1632 #else
1633                         set_local_var(p, 0);
1634 #endif
1635                         if (p != child->argv[i]) {
1636                                 child->sp--;
1637                                 free(p);
1638                         }
1639                 }
1640                 if (child->sp) {
1641                         char * str = NULL;
1642
1643                         str = make_string((child->argv + i));
1644                         parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1645                         free(str);
1646                         return last_return_code;
1647                 }
1648 #ifndef __U_BOOT__
1649                 for (x = bltins; x->cmd; x++) {
1650                         if (strcmp(child->argv[i], x->cmd) == 0 ) {
1651                                 int squirrel[] = {-1, -1, -1};
1652                                 int rcode;
1653                                 if (x->function == builtin_exec && child->argv[i+1]==NULL) {
1654                                         debug_printf("magic exec\n");
1655                                         setup_redirects(child,NULL);
1656                                         return EXIT_SUCCESS;
1657                                 }
1658                                 debug_printf("builtin inline %s\n", child->argv[0]);
1659                                 /* XXX setup_redirects acts on file descriptors, not FILEs.
1660                                  * This is perfect for work that comes after exec().
1661                                  * Is it really safe for inline use?  Experimentally,
1662                                  * things seem to work with glibc. */
1663                                 setup_redirects(child, squirrel);
1664 #else
1665                         /* check ";", because ,example , argv consist from
1666                          * "help;flinfo" must not execute
1667                          */
1668                         if (strchr(child->argv[i], ';')) {
1669                                 printf ("Unknown command '%s' - try 'help' or use 'run' command\n",
1670                                         child->argv[i]);
1671                                 return -1;
1672                         }
1673                         /* Look up command in command table */
1674
1675
1676                         if ((cmdtp = find_cmd(child->argv[i])) == NULL) {
1677                                 printf ("Unknown command '%s' - try 'help'\n", child->argv[i]);
1678                                 return -1;      /* give up after bad command */
1679                         } else {
1680                                 int rcode;
1681 #if defined(CONFIG_CMD_BOOTD)
1682                                 /* avoid "bootd" recursion */
1683                                 if (cmdtp->cmd == do_bootd) {
1684                                         if (flag & CMD_FLAG_BOOTD) {
1685                                                 printf ("'bootd' recursion detected\n");
1686                                                 return -1;
1687                                         }
1688                                 else
1689                                         flag |= CMD_FLAG_BOOTD;
1690                                 }
1691 #endif
1692                                 /* found - check max args */
1693                                 if ((child->argc - i) > cmdtp->maxargs)
1694                                         return cmd_usage(cmdtp);
1695 #endif
1696                                 child->argv+=i;  /* XXX horrible hack */
1697 #ifndef __U_BOOT__
1698                                 rcode = x->function(child);
1699 #else
1700                                 /* OK - call function to do the command */
1701
1702                                 rcode = (cmdtp->cmd)
1703 (cmdtp, flag,child->argc-i,&child->argv[i]);
1704                                 if ( !cmdtp->repeatable )
1705                                         flag_repeat = 0;
1706
1707
1708 #endif
1709                                 child->argv-=i;  /* XXX restore hack so free() can work right */
1710 #ifndef __U_BOOT__
1711
1712                                 restore_redirects(squirrel);
1713 #endif
1714
1715                                 return rcode;
1716                         }
1717                 }
1718 #ifndef __U_BOOT__
1719         }
1720
1721         for (i = 0; i < pi->num_progs; i++) {
1722                 child = & (pi->progs[i]);
1723
1724                 /* pipes are inserted between pairs of commands */
1725                 if ((i + 1) < pi->num_progs) {
1726                         if (pipe(pipefds)<0) perror_msg_and_die("pipe");
1727                         nextout = pipefds[1];
1728                 } else {
1729                         nextout=1;
1730                         pipefds[0] = -1;
1731                 }
1732
1733                 /* XXX test for failed fork()? */
1734                 if (!(child->pid = fork())) {
1735                         /* Set the handling for job control signals back to the default.  */
1736                         signal(SIGINT, SIG_DFL);
1737                         signal(SIGQUIT, SIG_DFL);
1738                         signal(SIGTERM, SIG_DFL);
1739                         signal(SIGTSTP, SIG_DFL);
1740                         signal(SIGTTIN, SIG_DFL);
1741                         signal(SIGTTOU, SIG_DFL);
1742                         signal(SIGCHLD, SIG_DFL);
1743
1744                         close_all();
1745
1746                         if (nextin != 0) {
1747                                 dup2(nextin, 0);
1748                                 close(nextin);
1749                         }
1750                         if (nextout != 1) {
1751                                 dup2(nextout, 1);
1752                                 close(nextout);
1753                         }
1754                         if (pipefds[0]!=-1) {
1755                                 close(pipefds[0]);  /* opposite end of our output pipe */
1756                         }
1757
1758                         /* Like bash, explicit redirects override pipes,
1759                          * and the pipe fd is available for dup'ing. */
1760                         setup_redirects(child,NULL);
1761
1762                         if (interactive && pi->followup!=PIPE_BG) {
1763                                 /* If we (the child) win the race, put ourselves in the process
1764                                  * group whose leader is the first process in this pipe. */
1765                                 if (pi->pgrp < 0) {
1766                                         pi->pgrp = getpid();
1767                                 }
1768                                 if (setpgid(0, pi->pgrp) == 0) {
1769                                         tcsetpgrp(2, pi->pgrp);
1770                                 }
1771                         }
1772
1773                         pseudo_exec(child);
1774                 }
1775
1776
1777                 /* put our child in the process group whose leader is the
1778                    first process in this pipe */
1779                 if (pi->pgrp < 0) {
1780                         pi->pgrp = child->pid;
1781                 }
1782                 /* Don't check for errors.  The child may be dead already,
1783                  * in which case setpgid returns error code EACCES. */
1784                 setpgid(child->pid, pi->pgrp);
1785
1786                 if (nextin != 0)
1787                         close(nextin);
1788                 if (nextout != 1)
1789                         close(nextout);
1790
1791                 /* If there isn't another process, nextin is garbage
1792                    but it doesn't matter */
1793                 nextin = pipefds[0];
1794         }
1795 #endif
1796         return -1;
1797 }
1798
1799 static int run_list_real(struct pipe *pi)
1800 {
1801         char *save_name = NULL;
1802         char **list = NULL;
1803         char **save_list = NULL;
1804         struct pipe *rpipe;
1805         int flag_rep = 0;
1806 #ifndef __U_BOOT__
1807         int save_num_progs;
1808 #endif
1809         int rcode=0, flag_skip=1;
1810         int flag_restore = 0;
1811         int if_code=0, next_if_code=0;  /* need double-buffer to handle elif */
1812         reserved_style rmode, skip_more_in_this_rmode=RES_XXXX;
1813         /* check syntax for "for" */
1814         for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1815                 if ((rpipe->r_mode == RES_IN ||
1816                     rpipe->r_mode == RES_FOR) &&
1817                     (rpipe->next == NULL)) {
1818                                 syntax();
1819 #ifdef __U_BOOT__
1820                                 flag_repeat = 0;
1821 #endif
1822                                 return 1;
1823                 }
1824                 if ((rpipe->r_mode == RES_IN &&
1825                         (rpipe->next->r_mode == RES_IN &&
1826                         rpipe->next->progs->argv != NULL))||
1827                         (rpipe->r_mode == RES_FOR &&
1828                         rpipe->next->r_mode != RES_IN)) {
1829                                 syntax();
1830 #ifdef __U_BOOT__
1831                                 flag_repeat = 0;
1832 #endif
1833                                 return 1;
1834                 }
1835         }
1836         for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1837                 if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
1838                         pi->r_mode == RES_FOR) {
1839 #ifdef __U_BOOT__
1840                                 /* check Ctrl-C */
1841                                 ctrlc();
1842                                 if ((had_ctrlc())) {
1843                                         return 1;
1844                                 }
1845 #endif
1846                                 flag_restore = 0;
1847                                 if (!rpipe) {
1848                                         flag_rep = 0;
1849                                         rpipe = pi;
1850                                 }
1851                 }
1852                 rmode = pi->r_mode;
1853                 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);
1854                 if (rmode == skip_more_in_this_rmode && flag_skip) {
1855                         if (pi->followup == PIPE_SEQ) flag_skip=0;
1856                         continue;
1857                 }
1858                 flag_skip = 1;
1859                 skip_more_in_this_rmode = RES_XXXX;
1860                 if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
1861                 if (rmode == RES_THEN &&  if_code) continue;
1862                 if (rmode == RES_ELSE && !if_code) continue;
1863                 if (rmode == RES_ELIF && !if_code) break;
1864                 if (rmode == RES_FOR && pi->num_progs) {
1865                         if (!list) {
1866                                 /* if no variable values after "in" we skip "for" */
1867                                 if (!pi->next->progs->argv) continue;
1868                                 /* create list of variable values */
1869                                 list = make_list_in(pi->next->progs->argv,
1870                                         pi->progs->argv[0]);
1871                                 save_list = list;
1872                                 save_name = pi->progs->argv[0];
1873                                 pi->progs->argv[0] = NULL;
1874                                 flag_rep = 1;
1875                         }
1876                         if (!(*list)) {
1877                                 free(pi->progs->argv[0]);
1878                                 free(save_list);
1879                                 list = NULL;
1880                                 flag_rep = 0;
1881                                 pi->progs->argv[0] = save_name;
1882 #ifndef __U_BOOT__
1883                                 pi->progs->glob_result.gl_pathv[0] =
1884                                         pi->progs->argv[0];
1885 #endif
1886                                 continue;
1887                         } else {
1888                                 /* insert new value from list for variable */
1889                                 if (pi->progs->argv[0])
1890                                         free(pi->progs->argv[0]);
1891                                 pi->progs->argv[0] = *list++;
1892 #ifndef __U_BOOT__
1893                                 pi->progs->glob_result.gl_pathv[0] =
1894                                         pi->progs->argv[0];
1895 #endif
1896                         }
1897                 }
1898                 if (rmode == RES_IN) continue;
1899                 if (rmode == RES_DO) {
1900                         if (!flag_rep) continue;
1901                 }
1902                 if ((rmode == RES_DONE)) {
1903                         if (flag_rep) {
1904                                 flag_restore = 1;
1905                         } else {
1906                                 rpipe = NULL;
1907                         }
1908                 }
1909                 if (pi->num_progs == 0) continue;
1910 #ifndef __U_BOOT__
1911                 save_num_progs = pi->num_progs; /* save number of programs */
1912 #endif
1913                 rcode = run_pipe_real(pi);
1914                 debug_printf("run_pipe_real returned %d\n",rcode);
1915 #ifndef __U_BOOT__
1916                 if (rcode!=-1) {
1917                         /* We only ran a builtin: rcode was set by the return value
1918                          * of run_pipe_real(), and we don't need to wait for anything. */
1919                 } else if (pi->followup==PIPE_BG) {
1920                         /* XXX check bash's behavior with nontrivial pipes */
1921                         /* XXX compute jobid */
1922                         /* XXX what does bash do with attempts to background builtins? */
1923                         insert_bg_job(pi);
1924                         rcode = EXIT_SUCCESS;
1925                 } else {
1926                         if (interactive) {
1927                                 /* move the new process group into the foreground */
1928                                 if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1929                                         perror_msg("tcsetpgrp-3");
1930                                 rcode = checkjobs(pi);
1931                                 /* move the shell to the foreground */
1932                                 if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1933                                         perror_msg("tcsetpgrp-4");
1934                         } else {
1935                                 rcode = checkjobs(pi);
1936                         }
1937                         debug_printf("checkjobs returned %d\n",rcode);
1938                 }
1939                 last_return_code=rcode;
1940 #else
1941                 if (rcode < -1) {
1942                         last_return_code = -rcode - 2;
1943                         return -2;      /* exit */
1944                 }
1945                 last_return_code=(rcode == 0) ? 0 : 1;
1946 #endif
1947 #ifndef __U_BOOT__
1948                 pi->num_progs = save_num_progs; /* restore number of programs */
1949 #endif
1950                 if ( rmode == RES_IF || rmode == RES_ELIF )
1951                         next_if_code=rcode;  /* can be overwritten a number of times */
1952                 if (rmode == RES_WHILE)
1953                         flag_rep = !last_return_code;
1954                 if (rmode == RES_UNTIL)
1955                         flag_rep = last_return_code;
1956                 if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
1957                      (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
1958                         skip_more_in_this_rmode=rmode;
1959 #ifndef __U_BOOT__
1960                 checkjobs(NULL);
1961 #endif
1962         }
1963         return rcode;
1964 }
1965
1966 /* broken, of course, but OK for testing */
1967 static char *indenter(int i)
1968 {
1969         static char blanks[]="                                    ";
1970         return &blanks[sizeof(blanks)-i-1];
1971 }
1972
1973 /* return code is the exit status of the pipe */
1974 static int free_pipe(struct pipe *pi, int indent)
1975 {
1976         char **p;
1977         struct child_prog *child;
1978 #ifndef __U_BOOT__
1979         struct redir_struct *r, *rnext;
1980 #endif
1981         int a, i, ret_code=0;
1982         char *ind = indenter(indent);
1983
1984 #ifndef __U_BOOT__
1985         if (pi->stopped_progs > 0)
1986                 return ret_code;
1987         final_printf("%s run pipe: (pid %d)\n",ind,getpid());
1988 #endif
1989         for (i=0; i<pi->num_progs; i++) {
1990                 child = &pi->progs[i];
1991                 final_printf("%s  command %d:\n",ind,i);
1992                 if (child->argv) {
1993                         for (a=0,p=child->argv; *p; a++,p++) {
1994                                 final_printf("%s   argv[%d] = %s\n",ind,a,*p);
1995                         }
1996 #ifndef __U_BOOT__
1997                         globfree(&child->glob_result);
1998 #else
1999                         for (a = 0; a < child->argc; a++) {
2000                                 free(child->argv[a]);
2001                         }
2002                                         free(child->argv);
2003                         child->argc = 0;
2004 #endif
2005                         child->argv=NULL;
2006                 } else if (child->group) {
2007 #ifndef __U_BOOT__
2008                         final_printf("%s   begin group (subshell:%d)\n",ind, child->subshell);
2009 #endif
2010                         ret_code = free_pipe_list(child->group,indent+3);
2011                         final_printf("%s   end group\n",ind);
2012                 } else {
2013                         final_printf("%s   (nil)\n",ind);
2014                 }
2015 #ifndef __U_BOOT__
2016                 for (r=child->redirects; r; r=rnext) {
2017                         final_printf("%s   redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
2018                         if (r->dup == -1) {
2019                                 /* guard against the case >$FOO, where foo is unset or blank */
2020                                 if (r->word.gl_pathv) {
2021                                         final_printf(" %s\n", *r->word.gl_pathv);
2022                                         globfree(&r->word);
2023                                 }
2024                         } else {
2025                                 final_printf("&%d\n", r->dup);
2026                         }
2027                         rnext=r->next;
2028                         free(r);
2029                 }
2030                 child->redirects=NULL;
2031 #endif
2032         }
2033         free(pi->progs);   /* children are an array, they get freed all at once */
2034         pi->progs=NULL;
2035         return ret_code;
2036 }
2037
2038 static int free_pipe_list(struct pipe *head, int indent)
2039 {
2040         int rcode=0;   /* if list has no members */
2041         struct pipe *pi, *next;
2042         char *ind = indenter(indent);
2043         for (pi=head; pi; pi=next) {
2044                 final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
2045                 rcode = free_pipe(pi, indent);
2046                 final_printf("%s pipe followup code %d\n", ind, pi->followup);
2047                 next=pi->next;
2048                 pi->next=NULL;
2049                 free(pi);
2050         }
2051         return rcode;
2052 }
2053
2054 /* Select which version we will use */
2055 static int run_list(struct pipe *pi)
2056 {
2057         int rcode=0;
2058 #ifndef __U_BOOT__
2059         if (fake_mode==0) {
2060 #endif
2061                 rcode = run_list_real(pi);
2062 #ifndef __U_BOOT__
2063         }
2064 #endif
2065         /* free_pipe_list has the side effect of clearing memory
2066          * In the long run that function can be merged with run_list_real,
2067          * but doing that now would hobble the debugging effort. */
2068         free_pipe_list(pi,0);
2069         return rcode;
2070 }
2071
2072 /* The API for glob is arguably broken.  This routine pushes a non-matching
2073  * string into the output structure, removing non-backslashed backslashes.
2074  * If someone can prove me wrong, by performing this function within the
2075  * original glob(3) api, feel free to rewrite this routine into oblivion.
2076  * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
2077  * XXX broken if the last character is '\\', check that before calling.
2078  */
2079 #ifndef __U_BOOT__
2080 static int globhack(const char *src, int flags, glob_t *pglob)
2081 {
2082         int cnt=0, pathc;
2083         const char *s;
2084         char *dest;
2085         for (cnt=1, s=src; s && *s; s++) {
2086                 if (*s == '\\') s++;
2087                 cnt++;
2088         }
2089         dest = malloc(cnt);
2090         if (!dest) return GLOB_NOSPACE;
2091         if (!(flags & GLOB_APPEND)) {
2092                 pglob->gl_pathv=NULL;
2093                 pglob->gl_pathc=0;
2094                 pglob->gl_offs=0;
2095                 pglob->gl_offs=0;
2096         }
2097         pathc = ++pglob->gl_pathc;
2098         pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
2099         if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
2100         pglob->gl_pathv[pathc-1]=dest;
2101         pglob->gl_pathv[pathc]=NULL;
2102         for (s=src; s && *s; s++, dest++) {
2103                 if (*s == '\\') s++;
2104                 *dest = *s;
2105         }
2106         *dest='\0';
2107         return 0;
2108 }
2109
2110 /* XXX broken if the last character is '\\', check that before calling */
2111 static int glob_needed(const char *s)
2112 {
2113         for (; *s; s++) {
2114                 if (*s == '\\') s++;
2115                 if (strchr("*[?",*s)) return 1;
2116         }
2117         return 0;
2118 }
2119
2120 #if 0
2121 static void globprint(glob_t *pglob)
2122 {
2123         int i;
2124         debug_printf("glob_t at %p:\n", pglob);
2125         debug_printf("  gl_pathc=%d  gl_pathv=%p  gl_offs=%d  gl_flags=%d\n",
2126                 pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
2127         for (i=0; i<pglob->gl_pathc; i++)
2128                 debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
2129                         pglob->gl_pathv[i], pglob->gl_pathv[i]);
2130 }
2131 #endif
2132
2133 static int xglob(o_string *dest, int flags, glob_t *pglob)
2134 {
2135         int gr;
2136
2137         /* short-circuit for null word */
2138         /* we can code this better when the debug_printf's are gone */
2139         if (dest->length == 0) {
2140                 if (dest->nonnull) {
2141                         /* bash man page calls this an "explicit" null */
2142                         gr = globhack(dest->data, flags, pglob);
2143                         debug_printf("globhack returned %d\n",gr);
2144                 } else {
2145                         return 0;
2146                 }
2147         } else if (glob_needed(dest->data)) {
2148                 gr = glob(dest->data, flags, NULL, pglob);
2149                 debug_printf("glob returned %d\n",gr);
2150                 if (gr == GLOB_NOMATCH) {
2151                         /* quote removal, or more accurately, backslash removal */
2152                         gr = globhack(dest->data, flags, pglob);
2153                         debug_printf("globhack returned %d\n",gr);
2154                 }
2155         } else {
2156                 gr = globhack(dest->data, flags, pglob);
2157                 debug_printf("globhack returned %d\n",gr);
2158         }
2159         if (gr == GLOB_NOSPACE)
2160                 error_msg_and_die("out of memory during glob");
2161         if (gr != 0) { /* GLOB_ABORTED ? */
2162                 error_msg("glob(3) error %d",gr);
2163         }
2164         /* globprint(glob_target); */
2165         return gr;
2166 }
2167 #endif
2168
2169 #ifdef __U_BOOT__
2170 static char *get_dollar_var(char ch);
2171 #endif
2172
2173 /* This is used to get/check local shell variables */
2174 static char *get_local_var(const char *s)
2175 {
2176         struct variables *cur;
2177
2178         if (!s)
2179                 return NULL;
2180
2181 #ifdef __U_BOOT__
2182         if (*s == '$')
2183                 return get_dollar_var(s[1]);
2184 #endif
2185
2186         for (cur = top_vars; cur; cur=cur->next)
2187                 if(strcmp(cur->name, s)==0)
2188                         return cur->value;
2189         return NULL;
2190 }
2191
2192 /* This is used to set local shell variables
2193    flg_export==0 if only local (not exporting) variable
2194    flg_export==1 if "new" exporting environ
2195    flg_export>1  if current startup environ (not call putenv()) */
2196 int set_local_var(const char *s, int flg_export)
2197 {
2198         char *name, *value;
2199         int result=0;
2200         struct variables *cur;
2201
2202 #ifdef __U_BOOT__
2203         /* might be possible! */
2204         if (!isalpha(*s))
2205                 return -1;
2206 #endif
2207
2208         name=strdup(s);
2209
2210 #ifdef __U_BOOT__
2211         if (getenv(name) != NULL) {
2212                 printf ("ERROR: "
2213                                 "There is a global environment variable with the same name.\n");
2214                 free(name);
2215                 return -1;
2216         }
2217 #endif
2218         /* Assume when we enter this function that we are already in
2219          * NAME=VALUE format.  So the first order of business is to
2220          * split 's' on the '=' into 'name' and 'value' */
2221         value = strchr(name, '=');
2222         if (value==0 && ++value==0) {
2223                 free(name);
2224                 return -1;
2225         }
2226         *value++ = 0;
2227
2228         for(cur = top_vars; cur; cur = cur->next) {
2229                 if(strcmp(cur->name, name)==0)
2230                         break;
2231         }
2232
2233         if(cur) {
2234                 if(strcmp(cur->value, value)==0) {
2235                         if(flg_export>0 && cur->flg_export==0)
2236                                 cur->flg_export=flg_export;
2237                         else
2238                                 result++;
2239                 } else {
2240                         if(cur->flg_read_only) {
2241                                 error_msg("%s: readonly variable", name);
2242                                 result = -1;
2243                         } else {
2244                                 if(flg_export>0 || cur->flg_export>1)
2245                                         cur->flg_export=1;
2246                                 free(cur->value);
2247
2248                                 cur->value = strdup(value);
2249                         }
2250                 }
2251         } else {
2252                 cur = malloc(sizeof(struct variables));
2253                 if(!cur) {
2254                         result = -1;
2255                 } else {
2256                         cur->name = strdup(name);
2257                         if(cur->name == 0) {
2258                                 free(cur);
2259                                 result = -1;
2260                         } else {
2261                                 struct variables *bottom = top_vars;
2262                                 cur->value = strdup(value);
2263                                 cur->next = 0;
2264                                 cur->flg_export = flg_export;
2265                                 cur->flg_read_only = 0;
2266                                 while(bottom->next) bottom=bottom->next;
2267                                 bottom->next = cur;
2268                         }
2269                 }
2270         }
2271
2272 #ifndef __U_BOOT__
2273         if(result==0 && cur->flg_export==1) {
2274                 *(value-1) = '=';
2275                 result = putenv(name);
2276         } else {
2277 #endif
2278                 free(name);
2279 #ifndef __U_BOOT__
2280                 if(result>0)            /* equivalent to previous set */
2281                         result = 0;
2282         }
2283 #endif
2284         return result;
2285 }
2286
2287 void unset_local_var(const char *name)
2288 {
2289         struct variables *cur;
2290
2291         if (name) {
2292                 for (cur = top_vars; cur; cur=cur->next) {
2293                         if(strcmp(cur->name, name)==0)
2294                                 break;
2295                 }
2296                 if(cur!=0) {
2297                         struct variables *next = top_vars;
2298                         if(cur->flg_read_only) {
2299                                 error_msg("%s: readonly variable", name);
2300                                 return;
2301                         } else {
2302 #ifndef __U_BOOT__
2303                                 if(cur->flg_export)
2304                                         unsetenv(cur->name);
2305 #endif
2306                                 free(cur->name);
2307                                 free(cur->value);
2308                                 while (next->next != cur)
2309                                         next = next->next;
2310                                 next->next = cur->next;
2311                         }
2312                         free(cur);
2313                 }
2314         }
2315 }
2316
2317 static int is_assignment(const char *s)
2318 {
2319         if (s == NULL)
2320                 return 0;
2321
2322         if (!isalpha(*s)) return 0;
2323         ++s;
2324         while(isalnum(*s) || *s=='_') ++s;
2325         return *s=='=';
2326 }
2327
2328 #ifndef __U_BOOT__
2329 /* the src parameter allows us to peek forward to a possible &n syntax
2330  * for file descriptor duplication, e.g., "2>&1".
2331  * Return code is 0 normally, 1 if a syntax error is detected in src.
2332  * Resource errors (in xmalloc) cause the process to exit */
2333 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
2334         struct in_str *input)
2335 {
2336         struct child_prog *child=ctx->child;
2337         struct redir_struct *redir = child->redirects;
2338         struct redir_struct *last_redir=NULL;
2339
2340         /* Create a new redir_struct and drop it onto the end of the linked list */
2341         while(redir) {
2342                 last_redir=redir;
2343                 redir=redir->next;
2344         }
2345         redir = xmalloc(sizeof(struct redir_struct));
2346         redir->next=NULL;
2347         redir->word.gl_pathv=NULL;
2348         if (last_redir) {
2349                 last_redir->next=redir;
2350         } else {
2351                 child->redirects=redir;
2352         }
2353
2354         redir->type=style;
2355         redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
2356
2357         debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
2358
2359         /* Check for a '2>&1' type redirect */
2360         redir->dup = redirect_dup_num(input);
2361         if (redir->dup == -2) return 1;  /* syntax error */
2362         if (redir->dup != -1) {
2363                 /* Erik had a check here that the file descriptor in question
2364                  * is legit; I postpone that to "run time"
2365                  * A "-" representation of "close me" shows up as a -3 here */
2366                 debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
2367         } else {
2368                 /* We do _not_ try to open the file that src points to,
2369                  * since we need to return and let src be expanded first.
2370                  * Set ctx->pending_redirect, so we know what to do at the
2371                  * end of the next parsed word.
2372                  */
2373                 ctx->pending_redirect = redir;
2374         }
2375         return 0;
2376 }
2377 #endif
2378
2379 struct pipe *new_pipe(void) {
2380         struct pipe *pi;
2381         pi = xmalloc(sizeof(struct pipe));
2382         pi->num_progs = 0;
2383         pi->progs = NULL;
2384         pi->next = NULL;
2385         pi->followup = 0;  /* invalid */
2386         pi->r_mode = RES_NONE;
2387         return pi;
2388 }
2389
2390 static void initialize_context(struct p_context *ctx)
2391 {
2392         ctx->pipe=NULL;
2393 #ifndef __U_BOOT__
2394         ctx->pending_redirect=NULL;
2395 #endif
2396         ctx->child=NULL;
2397         ctx->list_head=new_pipe();
2398         ctx->pipe=ctx->list_head;
2399         ctx->w=RES_NONE;
2400         ctx->stack=NULL;
2401 #ifdef __U_BOOT__
2402         ctx->old_flag=0;
2403 #endif
2404         done_command(ctx);   /* creates the memory for working child */
2405 }
2406
2407 /* normal return is 0
2408  * if a reserved word is found, and processed, return 1
2409  * should handle if, then, elif, else, fi, for, while, until, do, done.
2410  * case, function, and select are obnoxious, save those for later.
2411  */
2412 struct reserved_combo {
2413         char *literal;
2414         int code;
2415         long flag;
2416 };
2417 /* Mostly a list of accepted follow-up reserved words.
2418  * FLAG_END means we are done with the sequence, and are ready
2419  * to turn the compound list into a command.
2420  * FLAG_START means the word must start a new compound list.
2421  */
2422 static struct reserved_combo reserved_list[] = {
2423         { "if",    RES_IF,    FLAG_THEN | FLAG_START },
2424         { "then",  RES_THEN,  FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2425         { "elif",  RES_ELIF,  FLAG_THEN },
2426         { "else",  RES_ELSE,  FLAG_FI   },
2427         { "fi",    RES_FI,    FLAG_END  },
2428         { "for",   RES_FOR,   FLAG_IN   | FLAG_START },
2429         { "while", RES_WHILE, FLAG_DO   | FLAG_START },
2430         { "until", RES_UNTIL, FLAG_DO   | FLAG_START },
2431         { "in",    RES_IN,    FLAG_DO   },
2432         { "do",    RES_DO,    FLAG_DONE },
2433         { "done",  RES_DONE,  FLAG_END  }
2434 };
2435 #define NRES (sizeof(reserved_list)/sizeof(struct reserved_combo))
2436
2437 int reserved_word(o_string *dest, struct p_context *ctx)
2438 {
2439         struct reserved_combo *r;
2440         for (r=reserved_list;
2441                 r<reserved_list+NRES; r++) {
2442                 if (strcmp(dest->data, r->literal) == 0) {
2443                         debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2444                         if (r->flag & FLAG_START) {
2445                                 struct p_context *new = xmalloc(sizeof(struct p_context));
2446                                 debug_printf("push stack\n");
2447                                 if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2448                                         syntax();
2449                                         free(new);
2450                                         ctx->w = RES_SNTX;
2451                                         b_reset(dest);
2452                                         return 1;
2453                                 }
2454                                 *new = *ctx;   /* physical copy */
2455                                 initialize_context(ctx);
2456                                 ctx->stack=new;
2457                         } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2458                                 syntax();
2459                                 ctx->w = RES_SNTX;
2460                                 b_reset(dest);
2461                                 return 1;
2462                         }
2463                         ctx->w=r->code;
2464                         ctx->old_flag = r->flag;
2465                         if (ctx->old_flag & FLAG_END) {
2466                                 struct p_context *old;
2467                                 debug_printf("pop stack\n");
2468                                 done_pipe(ctx,PIPE_SEQ);
2469                                 old = ctx->stack;
2470                                 old->child->group = ctx->list_head;
2471 #ifndef __U_BOOT__
2472                                 old->child->subshell = 0;
2473 #endif
2474                                 *ctx = *old;   /* physical copy */
2475                                 free(old);
2476                         }
2477                         b_reset (dest);
2478                         return 1;
2479                 }
2480         }
2481         return 0;
2482 }
2483
2484 /* normal return is 0.
2485  * Syntax or xglob errors return 1. */
2486 static int done_word(o_string *dest, struct p_context *ctx)
2487 {
2488         struct child_prog *child=ctx->child;
2489 #ifndef __U_BOOT__
2490         glob_t *glob_target;
2491         int gr, flags = 0;
2492 #else
2493         char *str, *s;
2494         int argc, cnt;
2495 #endif
2496
2497         debug_printf("done_word: %s %p\n", dest->data, child);
2498         if (dest->length == 0 && !dest->nonnull) {
2499                 debug_printf("  true null, ignored\n");
2500                 return 0;
2501         }
2502 #ifndef __U_BOOT__
2503         if (ctx->pending_redirect) {
2504                 glob_target = &ctx->pending_redirect->word;
2505         } else {
2506 #endif
2507                 if (child->group) {
2508                         syntax();
2509                         return 1;  /* syntax error, groups and arglists don't mix */
2510                 }
2511                 if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2512                         debug_printf("checking %s for reserved-ness\n",dest->data);
2513                         if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2514                 }
2515 #ifndef __U_BOOT__
2516                 glob_target = &child->glob_result;
2517                 if (child->argv) flags |= GLOB_APPEND;
2518 #else
2519                 for (cnt = 1, s = dest->data; s && *s; s++) {
2520                         if (*s == '\\') s++;
2521                         cnt++;
2522                 }
2523                 str = malloc(cnt);
2524                 if (!str) return 1;
2525                 if ( child->argv == NULL) {
2526                         child->argc=0;
2527                 }
2528                 argc = ++child->argc;
2529                 child->argv = realloc(child->argv, (argc+1)*sizeof(*child->argv));
2530                 if (child->argv == NULL) return 1;
2531                 child->argv[argc-1]=str;
2532                 child->argv[argc]=NULL;
2533                 for (s = dest->data; s && *s; s++,str++) {
2534                         if (*s == '\\') s++;
2535                         *str = *s;
2536                 }
2537                 *str = '\0';
2538 #endif
2539 #ifndef __U_BOOT__
2540         }
2541         gr = xglob(dest, flags, glob_target);
2542         if (gr != 0) return 1;
2543 #endif
2544
2545         b_reset(dest);
2546 #ifndef __U_BOOT__
2547         if (ctx->pending_redirect) {
2548                 ctx->pending_redirect=NULL;
2549                 if (glob_target->gl_pathc != 1) {
2550                         error_msg("ambiguous redirect");
2551                         return 1;
2552                 }
2553         } else {
2554                 child->argv = glob_target->gl_pathv;
2555         }
2556 #endif
2557         if (ctx->w == RES_FOR) {
2558                 done_word(dest,ctx);
2559                 done_pipe(ctx,PIPE_SEQ);
2560         }
2561         return 0;
2562 }
2563
2564 /* The only possible error here is out of memory, in which case
2565  * xmalloc exits. */
2566 static int done_command(struct p_context *ctx)
2567 {
2568         /* The child is really already in the pipe structure, so
2569          * advance the pipe counter and make a new, null child.
2570          * Only real trickiness here is that the uncommitted
2571          * child structure, to which ctx->child points, is not
2572          * counted in pi->num_progs. */
2573         struct pipe *pi=ctx->pipe;
2574         struct child_prog *prog=ctx->child;
2575
2576         if (prog && prog->group == NULL
2577                  && prog->argv == NULL
2578 #ifndef __U_BOOT__
2579                  && prog->redirects == NULL) {
2580 #else
2581                                                                                 ) {
2582 #endif
2583                 debug_printf("done_command: skipping null command\n");
2584                 return 0;
2585         } else if (prog) {
2586                 pi->num_progs++;
2587                 debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2588         } else {
2589                 debug_printf("done_command: initializing\n");
2590         }
2591         pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2592
2593         prog = pi->progs + pi->num_progs;
2594 #ifndef __U_BOOT__
2595         prog->redirects = NULL;
2596 #endif
2597         prog->argv = NULL;
2598 #ifndef __U_BOOT__
2599         prog->is_stopped = 0;
2600 #endif
2601         prog->group = NULL;
2602 #ifndef __U_BOOT__
2603         prog->glob_result.gl_pathv = NULL;
2604         prog->family = pi;
2605 #endif
2606         prog->sp = 0;
2607         ctx->child = prog;
2608         prog->type = ctx->type;
2609
2610         /* but ctx->pipe and ctx->list_head remain unchanged */
2611         return 0;
2612 }
2613
2614 static int done_pipe(struct p_context *ctx, pipe_style type)
2615 {
2616         struct pipe *new_p;
2617         done_command(ctx);  /* implicit closure of previous command */
2618         debug_printf("done_pipe, type %d\n", type);
2619         ctx->pipe->followup = type;
2620         ctx->pipe->r_mode = ctx->w;
2621         new_p=new_pipe();
2622         ctx->pipe->next = new_p;
2623         ctx->pipe = new_p;
2624         ctx->child = NULL;
2625         done_command(ctx);  /* set up new pipe to accept commands */
2626         return 0;
2627 }
2628
2629 #ifndef __U_BOOT__
2630 /* peek ahead in the in_str to find out if we have a "&n" construct,
2631  * as in "2>&1", that represents duplicating a file descriptor.
2632  * returns either -2 (syntax error), -1 (no &), or the number found.
2633  */
2634 static int redirect_dup_num(struct in_str *input)
2635 {
2636         int ch, d=0, ok=0;
2637         ch = b_peek(input);
2638         if (ch != '&') return -1;
2639
2640         b_getch(input);  /* get the & */
2641         ch=b_peek(input);
2642         if (ch == '-') {
2643                 b_getch(input);
2644                 return -3;  /* "-" represents "close me" */
2645         }
2646         while (isdigit(ch)) {
2647                 d = d*10+(ch-'0');
2648                 ok=1;
2649                 b_getch(input);
2650                 ch = b_peek(input);
2651         }
2652         if (ok) return d;
2653
2654         error_msg("ambiguous redirect");
2655         return -2;
2656 }
2657
2658 /* If a redirect is immediately preceded by a number, that number is
2659  * supposed to tell which file descriptor to redirect.  This routine
2660  * looks for such preceding numbers.  In an ideal world this routine
2661  * needs to handle all the following classes of redirects...
2662  *     echo 2>foo     # redirects fd  2 to file "foo", nothing passed to echo
2663  *     echo 49>foo    # redirects fd 49 to file "foo", nothing passed to echo
2664  *     echo -2>foo    # redirects fd  1 to file "foo",    "-2" passed to echo
2665  *     echo 49x>foo   # redirects fd  1 to file "foo",   "49x" passed to echo
2666  * A -1 output from this program means no valid number was found, so the
2667  * caller should use the appropriate default for this redirection.
2668  */
2669 static int redirect_opt_num(o_string *o)
2670 {
2671         int num;
2672
2673         if (o->length==0) return -1;
2674         for(num=0; num<o->length; num++) {
2675                 if (!isdigit(*(o->data+num))) {
2676                         return -1;
2677                 }
2678         }
2679         /* reuse num (and save an int) */
2680         num=atoi(o->data);
2681         b_reset(o);
2682         return num;
2683 }
2684
2685 FILE *generate_stream_from_list(struct pipe *head)
2686 {
2687         FILE *pf;
2688 #if 1
2689         int pid, channel[2];
2690         if (pipe(channel)<0) perror_msg_and_die("pipe");
2691         pid=fork();
2692         if (pid<0) {
2693                 perror_msg_and_die("fork");
2694         } else if (pid==0) {
2695                 close(channel[0]);
2696                 if (channel[1] != 1) {
2697                         dup2(channel[1],1);
2698                         close(channel[1]);
2699                 }
2700 #if 0
2701 #define SURROGATE "surrogate response"
2702                 write(1,SURROGATE,sizeof(SURROGATE));
2703                 _exit(run_list(head));
2704 #else
2705                 _exit(run_list_real(head));   /* leaks memory */
2706 #endif
2707         }
2708         debug_printf("forked child %d\n",pid);
2709         close(channel[1]);
2710         pf = fdopen(channel[0],"r");
2711         debug_printf("pipe on FILE *%p\n",pf);
2712 #else
2713         free_pipe_list(head,0);
2714         pf=popen("echo surrogate response","r");
2715         debug_printf("started fake pipe on FILE *%p\n",pf);
2716 #endif
2717         return pf;
2718 }
2719
2720 /* this version hacked for testing purposes */
2721 /* return code is exit status of the process that is run. */
2722 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2723 {
2724         int retcode;
2725         o_string result=NULL_O_STRING;
2726         struct p_context inner;
2727         FILE *p;
2728         struct in_str pipe_str;
2729         initialize_context(&inner);
2730
2731         /* recursion to generate command */
2732         retcode = parse_stream(&result, &inner, input, subst_end);
2733         if (retcode != 0) return retcode;  /* syntax error or EOF */
2734         done_word(&result, &inner);
2735         done_pipe(&inner, PIPE_SEQ);
2736         b_free(&result);
2737
2738         p=generate_stream_from_list(inner.list_head);
2739         if (p==NULL) return 1;
2740         mark_open(fileno(p));
2741         setup_file_in_str(&pipe_str, p);
2742
2743         /* now send results of command back into original context */
2744         retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2745         /* XXX In case of a syntax error, should we try to kill the child?
2746          * That would be tough to do right, so just read until EOF. */
2747         if (retcode == 1) {
2748                 while (b_getch(&pipe_str)!=EOF) { /* discard */ };
2749         }
2750
2751         debug_printf("done reading from pipe, pclose()ing\n");
2752         /* This is the step that wait()s for the child.  Should be pretty
2753          * safe, since we just read an EOF from its stdout.  We could try
2754          * to better, by using wait(), and keeping track of background jobs
2755          * at the same time.  That would be a lot of work, and contrary
2756          * to the KISS philosophy of this program. */
2757         mark_closed(fileno(p));
2758         retcode=pclose(p);
2759         free_pipe_list(inner.list_head,0);
2760         debug_printf("pclosed, retcode=%d\n",retcode);
2761         /* XXX this process fails to trim a single trailing newline */
2762         return retcode;
2763 }
2764
2765 static int parse_group(o_string *dest, struct p_context *ctx,
2766         struct in_str *input, int ch)
2767 {
2768         int rcode, endch=0;
2769         struct p_context sub;
2770         struct child_prog *child = ctx->child;
2771         if (child->argv) {
2772                 syntax();
2773                 return 1;  /* syntax error, groups and arglists don't mix */
2774         }
2775         initialize_context(&sub);
2776         switch(ch) {
2777                 case '(': endch=')'; child->subshell=1; break;
2778                 case '{': endch='}'; break;
2779                 default: syntax();   /* really logic error */
2780         }
2781         rcode=parse_stream(dest,&sub,input,endch);
2782         done_word(dest,&sub); /* finish off the final word in the subcontext */
2783         done_pipe(&sub, PIPE_SEQ);  /* and the final command there, too */
2784         child->group = sub.list_head;
2785         return rcode;
2786         /* child remains "open", available for possible redirects */
2787 }
2788 #endif
2789
2790 /* basically useful version until someone wants to get fancier,
2791  * see the bash man page under "Parameter Expansion" */
2792 static char *lookup_param(char *src)
2793 {
2794         char *p;
2795
2796         if (!src)
2797                 return NULL;
2798
2799                 p = getenv(src);
2800                 if (!p)
2801                         p = get_local_var(src);
2802
2803         return p;
2804 }
2805
2806 #ifdef __U_BOOT__
2807 static char *get_dollar_var(char ch)
2808 {
2809         static char buf[40];
2810
2811         buf[0] = '\0';
2812         switch (ch) {
2813                 case '?':
2814                         sprintf(buf, "%u", (unsigned int)last_return_code);
2815                         break;
2816                 default:
2817                         return NULL;
2818         }
2819         return buf;
2820 }
2821 #endif
2822
2823 /* return code: 0 for OK, 1 for syntax error */
2824 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2825 {
2826 #ifndef __U_BOOT__
2827         int i, advance=0;
2828 #else
2829         int advance=0;
2830 #endif
2831 #ifndef __U_BOOT__
2832         char sep[]=" ";
2833 #endif
2834         int ch = input->peek(input);  /* first character after the $ */
2835         debug_printf("handle_dollar: ch=%c\n",ch);
2836         if (isalpha(ch)) {
2837                 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2838                 ctx->child->sp++;
2839                 while(ch=b_peek(input),isalnum(ch) || ch=='_') {
2840                         b_getch(input);
2841                         b_addchr(dest,ch);
2842                 }
2843                 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2844 #ifndef __U_BOOT__
2845         } else if (isdigit(ch)) {
2846                 i = ch-'0';  /* XXX is $0 special? */
2847                 if (i<global_argc) {
2848                         parse_string(dest, ctx, global_argv[i]); /* recursion */
2849                 }
2850                 advance = 1;
2851 #endif
2852         } else switch (ch) {
2853 #ifndef __U_BOOT__
2854                 case '$':
2855                         b_adduint(dest,getpid());
2856                         advance = 1;
2857                         break;
2858                 case '!':
2859                         if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2860                         advance = 1;
2861                         break;
2862 #endif
2863                 case '?':
2864 #ifndef __U_BOOT__
2865                         b_adduint(dest,last_return_code);
2866 #else
2867                         ctx->child->sp++;
2868                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2869                         b_addchr(dest, '$');
2870                         b_addchr(dest, '?');
2871                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2872 #endif
2873                         advance = 1;
2874                         break;
2875 #ifndef __U_BOOT__
2876                 case '#':
2877                         b_adduint(dest,global_argc ? global_argc-1 : 0);
2878                         advance = 1;
2879                         break;
2880 #endif
2881                 case '{':
2882                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2883                         ctx->child->sp++;
2884                         b_getch(input);
2885                         /* XXX maybe someone will try to escape the '}' */
2886                         while(ch=b_getch(input),ch!=EOF && ch!='}') {
2887                                 b_addchr(dest,ch);
2888                         }
2889                         if (ch != '}') {
2890                                 syntax();
2891                                 return 1;
2892                         }
2893                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2894                         break;
2895 #ifndef __U_BOOT__
2896                 case '(':
2897                         b_getch(input);
2898                         process_command_subs(dest, ctx, input, ')');
2899                         break;
2900                 case '*':
2901                         sep[0]=ifs[0];
2902                         for (i=1; i<global_argc; i++) {
2903                                 parse_string(dest, ctx, global_argv[i]);
2904                                 if (i+1 < global_argc) parse_string(dest, ctx, sep);
2905                         }
2906                         break;
2907                 case '@':
2908                 case '-':
2909                 case '_':
2910                         /* still unhandled, but should be eventually */
2911                         error_msg("unhandled syntax: $%c",ch);
2912                         return 1;
2913                         break;
2914 #endif
2915                 default:
2916                         b_addqchr(dest,'$',dest->quote);
2917         }
2918         /* Eat the character if the flag was set.  If the compiler
2919          * is smart enough, we could substitute "b_getch(input);"
2920          * for all the "advance = 1;" above, and also end up with
2921          * a nice size-optimized program.  Hah!  That'll be the day.
2922          */
2923         if (advance) b_getch(input);
2924         return 0;
2925 }
2926
2927 #ifndef __U_BOOT__
2928 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2929 {
2930         struct in_str foo;
2931         setup_string_in_str(&foo, src);
2932         return parse_stream(dest, ctx, &foo, '\0');
2933 }
2934 #endif
2935
2936 /* return code is 0 for normal exit, 1 for syntax error */
2937 int parse_stream(o_string *dest, struct p_context *ctx,
2938         struct in_str *input, int end_trigger)
2939 {
2940         unsigned int ch, m;
2941 #ifndef __U_BOOT__
2942         int redir_fd;
2943         redir_type redir_style;
2944 #endif
2945         int next;
2946
2947         /* Only double-quote state is handled in the state variable dest->quote.
2948          * A single-quote triggers a bypass of the main loop until its mate is
2949          * found.  When recursing, quote state is passed in via dest->quote. */
2950
2951         debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2952         while ((ch=b_getch(input))!=EOF) {
2953                 m = map[ch];
2954 #ifdef __U_BOOT__
2955                 if (input->__promptme == 0) return 1;
2956 #endif
2957                 next = (ch == '\n') ? 0 : b_peek(input);
2958
2959                 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d - %c\n",
2960                         ch >= ' ' ? ch : '.', ch, m,
2961                         dest->quote, ctx->stack == NULL ? '*' : '.');
2962
2963                 if (m==0 || ((m==1 || m==2) && dest->quote)) {
2964                         b_addqchr(dest, ch, dest->quote);
2965                 } else {
2966                         if (m==2) {  /* unquoted IFS */
2967                                 if (done_word(dest, ctx)) {
2968                                         return 1;
2969                                 }
2970                                 /* If we aren't performing a substitution, treat a newline as a
2971                                  * command separator.  */
2972                                 if (end_trigger != '\0' && ch=='\n')
2973                                         done_pipe(ctx,PIPE_SEQ);
2974                         }
2975                         if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2976                                 debug_printf("leaving parse_stream (triggered)\n");
2977                                 return 0;
2978                         }
2979 #if 0
2980                         if (ch=='\n') {
2981                                 /* Yahoo!  Time to run with it! */
2982                                 done_pipe(ctx,PIPE_SEQ);
2983                                 run_list(ctx->list_head);
2984                                 initialize_context(ctx);
2985                         }
2986 #endif
2987                         if (m!=2) switch (ch) {
2988                 case '#':
2989                         if (dest->length == 0 && !dest->quote) {
2990                                 while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
2991                         } else {
2992                                 b_addqchr(dest, ch, dest->quote);
2993                         }
2994                         break;
2995                 case '\\':
2996                         if (next == EOF) {
2997                                 syntax();
2998                                 return 1;
2999                         }
3000                         b_addqchr(dest, '\\', dest->quote);
3001                         b_addqchr(dest, b_getch(input), dest->quote);
3002                         break;
3003                 case '$':
3004                         if (handle_dollar(dest, ctx, input)!=0) return 1;
3005                         break;
3006                 case '\'':
3007                         dest->nonnull = 1;
3008                         while(ch=b_getch(input),ch!=EOF && ch!='\'') {
3009 #ifdef __U_BOOT__
3010                                 if(input->__promptme == 0) return 1;
3011 #endif
3012                                 b_addchr(dest,ch);
3013                         }
3014                         if (ch==EOF) {
3015                                 syntax();
3016                                 return 1;
3017                         }
3018                         break;
3019                 case '"':
3020                         dest->nonnull = 1;
3021                         dest->quote = !dest->quote;
3022                         break;
3023 #ifndef __U_BOOT__
3024                 case '`':
3025                         process_command_subs(dest, ctx, input, '`');
3026                         break;
3027                 case '>':
3028                         redir_fd = redirect_opt_num(dest);
3029                         done_word(dest, ctx);
3030                         redir_style=REDIRECT_OVERWRITE;
3031                         if (next == '>') {
3032                                 redir_style=REDIRECT_APPEND;
3033                                 b_getch(input);
3034                         } else if (next == '(') {
3035                                 syntax();   /* until we support >(list) Process Substitution */
3036                                 return 1;
3037                         }
3038                         setup_redirect(ctx, redir_fd, redir_style, input);
3039                         break;
3040                 case '<':
3041                         redir_fd = redirect_opt_num(dest);
3042                         done_word(dest, ctx);
3043                         redir_style=REDIRECT_INPUT;
3044                         if (next == '<') {
3045                                 redir_style=REDIRECT_HEREIS;
3046                                 b_getch(input);
3047                         } else if (next == '>') {
3048                                 redir_style=REDIRECT_IO;
3049                                 b_getch(input);
3050                         } else if (next == '(') {
3051                                 syntax();   /* until we support <(list) Process Substitution */
3052                                 return 1;
3053                         }
3054                         setup_redirect(ctx, redir_fd, redir_style, input);
3055                         break;
3056 #endif
3057                 case ';':
3058                         done_word(dest, ctx);
3059                         done_pipe(ctx,PIPE_SEQ);
3060                         break;
3061                 case '&':
3062                         done_word(dest, ctx);
3063                         if (next=='&') {
3064                                 b_getch(input);
3065                                 done_pipe(ctx,PIPE_AND);
3066                         } else {
3067 #ifndef __U_BOOT__
3068                                 done_pipe(ctx,PIPE_BG);
3069 #else
3070                                 syntax_err();
3071                                 return 1;
3072 #endif
3073                         }
3074                         break;
3075                 case '|':
3076                         done_word(dest, ctx);
3077                         if (next=='|') {
3078                                 b_getch(input);
3079                                 done_pipe(ctx,PIPE_OR);
3080                         } else {
3081                                 /* we could pick up a file descriptor choice here
3082                                  * with redirect_opt_num(), but bash doesn't do it.
3083                                  * "echo foo 2| cat" yields "foo 2". */
3084 #ifndef __U_BOOT__
3085                                 done_command(ctx);
3086 #else
3087                                 syntax_err();
3088                                 return 1;
3089 #endif
3090                         }
3091                         break;
3092 #ifndef __U_BOOT__
3093                 case '(':
3094                 case '{':
3095                         if (parse_group(dest, ctx, input, ch)!=0) return 1;
3096                         break;
3097                 case ')':
3098                 case '}':
3099                         syntax();   /* Proper use of this character caught by end_trigger */
3100                         return 1;
3101                         break;
3102 #endif
3103                 default:
3104                         syntax();   /* this is really an internal logic error */
3105                         return 1;
3106                         }
3107                 }
3108         }
3109         /* complain if quote?  No, maybe we just finished a command substitution
3110          * that was quoted.  Example:
3111          * $ echo "`cat foo` plus more"
3112          * and we just got the EOF generated by the subshell that ran "cat foo"
3113          * The only real complaint is if we got an EOF when end_trigger != '\0',
3114          * that is, we were really supposed to get end_trigger, and never got
3115          * one before the EOF.  Can't use the standard "syntax error" return code,
3116          * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
3117         debug_printf("leaving parse_stream (EOF)\n");
3118         if (end_trigger != '\0') return -1;
3119         return 0;
3120 }
3121
3122 void mapset(const unsigned char *set, int code)
3123 {
3124         const unsigned char *s;
3125         for (s=set; *s; s++) map[*s] = code;
3126 }
3127
3128 void update_ifs_map(void)
3129 {
3130         /* char *ifs and char map[256] are both globals. */
3131         ifs = (uchar *)getenv("IFS");
3132         if (ifs == NULL) ifs=(uchar *)" \t\n";
3133         /* Precompute a list of 'flow through' behavior so it can be treated
3134          * quickly up front.  Computation is necessary because of IFS.
3135          * Special case handling of IFS == " \t\n" is not implemented.
3136          * The map[] array only really needs two bits each, and on most machines
3137          * that would be faster because of the reduced L1 cache footprint.
3138          */
3139         memset(map,0,sizeof(map)); /* most characters flow through always */
3140 #ifndef __U_BOOT__
3141         mapset((uchar *)"\\$'\"`", 3);      /* never flow through */
3142         mapset((uchar *)"<>;&|(){}#", 1);   /* flow through if quoted */
3143 #else
3144         mapset((uchar *)"\\$'\"", 3);       /* never flow through */
3145         mapset((uchar *)";&|#", 1);         /* flow through if quoted */
3146 #endif
3147         mapset(ifs, 2);            /* also flow through if quoted */
3148 }
3149
3150 /* most recursion does not come through here, the exeception is
3151  * from builtin_source() */
3152 int parse_stream_outer(struct in_str *inp, int flag)
3153 {
3154
3155         struct p_context ctx;
3156         o_string temp=NULL_O_STRING;
3157         int rcode;
3158 #ifdef __U_BOOT__
3159         int code = 0;
3160 #endif
3161         do {
3162                 ctx.type = flag;
3163                 initialize_context(&ctx);
3164                 update_ifs_map();
3165                 if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset((uchar *)";$&|", 0);
3166                 inp->promptmode=1;
3167                 rcode = parse_stream(&temp, &ctx, inp, '\n');
3168 #ifdef __U_BOOT__
3169                 if (rcode == 1) flag_repeat = 0;
3170 #endif
3171                 if (rcode != 1 && ctx.old_flag != 0) {
3172                         syntax();
3173 #ifdef __U_BOOT__
3174                         flag_repeat = 0;
3175 #endif
3176                 }
3177                 if (rcode != 1 && ctx.old_flag == 0) {
3178                         done_word(&temp, &ctx);
3179                         done_pipe(&ctx,PIPE_SEQ);
3180 #ifndef __U_BOOT__
3181                         run_list(ctx.list_head);
3182 #else
3183                         code = run_list(ctx.list_head);
3184                         if (code == -2) {       /* exit */
3185                                 b_free(&temp);
3186                                 code = 0;
3187                                 /* XXX hackish way to not allow exit from main loop */
3188                                 if (inp->peek == file_peek) {
3189                                         printf("exit not allowed from main input shell.\n");
3190                                         continue;
3191                                 }
3192                                 break;
3193                         }
3194                         if (code == -1)
3195                             flag_repeat = 0;
3196 #endif
3197                 } else {
3198                         if (ctx.old_flag != 0) {
3199                                 free(ctx.stack);
3200                                 b_reset(&temp);
3201                         }
3202 #ifdef __U_BOOT__
3203                         if (inp->__promptme == 0) printf("<INTERRUPT>\n");
3204                         inp->__promptme = 1;
3205 #endif
3206                         temp.nonnull = 0;
3207                         temp.quote = 0;
3208                         inp->p = NULL;
3209                         free_pipe_list(ctx.list_head,0);
3210                 }
3211                 b_free(&temp);
3212         } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP));   /* loop on syntax errors, return on EOF */
3213 #ifndef __U_BOOT__
3214         return 0;
3215 #else
3216         return (code != 0) ? 1 : 0;
3217 #endif /* __U_BOOT__ */
3218 }
3219
3220 #ifndef __U_BOOT__
3221 static int parse_string_outer(const char *s, int flag)
3222 #else
3223 int parse_string_outer(char *s, int flag)
3224 #endif  /* __U_BOOT__ */
3225 {
3226         struct in_str input;
3227 #ifdef __U_BOOT__
3228         char *p = NULL;
3229         int rcode;
3230         if ( !s || !*s)
3231                 return 1;
3232         if (!(p = strchr(s, '\n')) || *++p) {
3233                 p = xmalloc(strlen(s) + 2);
3234                 strcpy(p, s);
3235                 strcat(p, "\n");
3236                 setup_string_in_str(&input, p);
3237                 rcode = parse_stream_outer(&input, flag);
3238                 free(p);
3239                 return rcode;
3240         } else {
3241 #endif
3242         setup_string_in_str(&input, s);
3243         return parse_stream_outer(&input, flag);
3244 #ifdef __U_BOOT__
3245         }
3246 #endif
3247 }
3248
3249 #ifndef __U_BOOT__
3250 static int parse_file_outer(FILE *f)
3251 #else
3252 int parse_file_outer(void)
3253 #endif
3254 {
3255         int rcode;
3256         struct in_str input;
3257 #ifndef __U_BOOT__
3258         setup_file_in_str(&input, f);
3259 #else
3260         setup_file_in_str(&input);
3261 #endif
3262         rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
3263         return rcode;
3264 }
3265
3266 #ifdef __U_BOOT__
3267 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3268 static void u_boot_hush_reloc(void)
3269 {
3270         unsigned long addr;
3271         struct reserved_combo *r;
3272
3273         for (r=reserved_list; r<reserved_list+NRES; r++) {
3274                 addr = (ulong) (r->literal) + gd->reloc_off;
3275                 r->literal = (char *)addr;
3276         }
3277 }
3278 #endif
3279
3280 int u_boot_hush_start(void)
3281 {
3282         if (top_vars == NULL) {
3283                 top_vars = malloc(sizeof(struct variables));
3284                 top_vars->name = "HUSH_VERSION";
3285                 top_vars->value = "0.01";
3286                 top_vars->next = 0;
3287                 top_vars->flg_export = 0;
3288                 top_vars->flg_read_only = 1;
3289 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3290                 u_boot_hush_reloc();
3291 #endif
3292         }
3293         return 0;
3294 }
3295
3296 static void *xmalloc(size_t size)
3297 {
3298         void *p = NULL;
3299
3300         if (!(p = malloc(size))) {
3301             printf("ERROR : memory not allocated\n");
3302             for(;;);
3303         }
3304         return p;
3305 }
3306
3307 static void *xrealloc(void *ptr, size_t size)
3308 {
3309         void *p = NULL;
3310
3311         if (!(p = realloc(ptr, size))) {
3312             printf("ERROR : memory not allocated\n");
3313             for(;;);
3314         }
3315         return p;
3316 }
3317 #endif /* __U_BOOT__ */
3318
3319 #ifndef __U_BOOT__
3320 /* Make sure we have a controlling tty.  If we get started under a job
3321  * aware app (like bash for example), make sure we are now in charge so
3322  * we don't fight over who gets the foreground */
3323 static void setup_job_control(void)
3324 {
3325         static pid_t shell_pgrp;
3326         /* Loop until we are in the foreground.  */
3327         while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
3328                 kill (- shell_pgrp, SIGTTIN);
3329
3330         /* Ignore interactive and job-control signals.  */
3331         signal(SIGINT, SIG_IGN);
3332         signal(SIGQUIT, SIG_IGN);
3333         signal(SIGTERM, SIG_IGN);
3334         signal(SIGTSTP, SIG_IGN);
3335         signal(SIGTTIN, SIG_IGN);
3336         signal(SIGTTOU, SIG_IGN);
3337         signal(SIGCHLD, SIG_IGN);
3338
3339         /* Put ourselves in our own process group.  */
3340         setsid();
3341         shell_pgrp = getpid ();
3342         setpgid (shell_pgrp, shell_pgrp);
3343
3344         /* Grab control of the terminal.  */
3345         tcsetpgrp(shell_terminal, shell_pgrp);
3346 }
3347
3348 int hush_main(int argc, char * const *argv)
3349 {
3350         int opt;
3351         FILE *input;
3352         char **e = environ;
3353
3354         /* XXX what should these be while sourcing /etc/profile? */
3355         global_argc = argc;
3356         global_argv = argv;
3357
3358         /* (re?) initialize globals.  Sometimes hush_main() ends up calling
3359          * hush_main(), therefore we cannot rely on the BSS to zero out this
3360          * stuff.  Reset these to 0 every time. */
3361         ifs = NULL;
3362         /* map[] is taken care of with call to update_ifs_map() */
3363         fake_mode = 0;
3364         interactive = 0;
3365         close_me_head = NULL;
3366         last_bg_pid = 0;
3367         job_list = NULL;
3368         last_jobid = 0;
3369
3370         /* Initialize some more globals to non-zero values */
3371         set_cwd();
3372 #ifdef CONFIG_FEATURE_COMMAND_EDITING
3373         cmdedit_set_initial_prompt();
3374 #else
3375         PS1 = NULL;
3376 #endif
3377         PS2 = "> ";
3378
3379         /* initialize our shell local variables with the values
3380          * currently living in the environment */
3381         if (e) {
3382                 for (; *e; e++)
3383                         set_local_var(*e, 2);   /* without call putenv() */
3384         }
3385
3386         last_return_code=EXIT_SUCCESS;
3387
3388
3389         if (argv[0] && argv[0][0] == '-') {
3390                 debug_printf("\nsourcing /etc/profile\n");
3391                 if ((input = fopen("/etc/profile", "r")) != NULL) {
3392                         mark_open(fileno(input));
3393                         parse_file_outer(input);
3394                         mark_closed(fileno(input));
3395                         fclose(input);
3396                 }
3397         }
3398         input=stdin;
3399
3400         while ((opt = getopt(argc, argv, "c:xif")) > 0) {
3401                 switch (opt) {
3402                         case 'c':
3403                                 {
3404                                         global_argv = argv+optind;
3405                                         global_argc = argc-optind;
3406                                         opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
3407                                         goto final_return;
3408                                 }
3409                                 break;
3410                         case 'i':
3411                                 interactive++;
3412                                 break;
3413                         case 'f':
3414                                 fake_mode++;
3415                                 break;
3416                         default:
3417 #ifndef BB_VER
3418                                 fprintf(stderr, "Usage: sh [FILE]...\n"
3419                                                 "   or: sh -c command [args]...\n\n");
3420                                 exit(EXIT_FAILURE);
3421 #else
3422                                 show_usage();
3423 #endif
3424                 }
3425         }
3426         /* A shell is interactive if the `-i' flag was given, or if all of
3427          * the following conditions are met:
3428          *        no -c command
3429          *    no arguments remaining or the -s flag given
3430          *    standard input is a terminal
3431          *    standard output is a terminal
3432          *    Refer to Posix.2, the description of the `sh' utility. */
3433         if (argv[optind]==NULL && input==stdin &&
3434                         isatty(fileno(stdin)) && isatty(fileno(stdout))) {
3435                 interactive++;
3436         }
3437
3438         debug_printf("\ninteractive=%d\n", interactive);
3439         if (interactive) {
3440                 /* Looks like they want an interactive shell */
3441 #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
3442                 printf( "\n\n" BB_BANNER " hush - the humble shell v0.01 (testing)\n");
3443                 printf( "Enter 'help' for a list of built-in commands.\n\n");
3444 #endif
3445                 setup_job_control();
3446         }
3447
3448         if (argv[optind]==NULL) {
3449                 opt=parse_file_outer(stdin);
3450                 goto final_return;
3451         }
3452
3453         debug_printf("\nrunning script '%s'\n", argv[optind]);
3454         global_argv = argv+optind;
3455         global_argc = argc-optind;
3456         input = xfopen(argv[optind], "r");
3457         opt = parse_file_outer(input);
3458
3459 #ifdef CONFIG_FEATURE_CLEAN_UP
3460         fclose(input);
3461         if (cwd && cwd != unknown)
3462                 free((char*)cwd);
3463         {
3464                 struct variables *cur, *tmp;
3465                 for(cur = top_vars; cur; cur = tmp) {
3466                         tmp = cur->next;
3467                         if (!cur->flg_read_only) {
3468                                 free(cur->name);
3469                                 free(cur->value);
3470                                 free(cur);
3471                         }
3472                 }
3473         }
3474 #endif
3475
3476 final_return:
3477         return(opt?opt:last_return_code);
3478 }
3479 #endif
3480
3481 static char *insert_var_value(char *inp)
3482 {
3483         int res_str_len = 0;
3484         int len;
3485         int done = 0;
3486         char *p, *p1, *res_str = NULL;
3487
3488         while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
3489                 if (p != inp) {
3490                         len = p - inp;
3491                         res_str = xrealloc(res_str, (res_str_len + len));
3492                         strncpy((res_str + res_str_len), inp, len);
3493                         res_str_len += len;
3494                 }
3495                 inp = ++p;
3496                 p = strchr(inp, SPECIAL_VAR_SYMBOL);
3497                 *p = '\0';
3498                 if ((p1 = lookup_param(inp))) {
3499                         len = res_str_len + strlen(p1);
3500                         res_str = xrealloc(res_str, (1 + len));
3501                         strcpy((res_str + res_str_len), p1);
3502                         res_str_len = len;
3503                 }
3504                 *p = SPECIAL_VAR_SYMBOL;
3505                 inp = ++p;
3506                 done = 1;
3507         }
3508         if (done) {
3509                 res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
3510                 strcpy((res_str + res_str_len), inp);
3511                 while ((p = strchr(res_str, '\n'))) {
3512                         *p = ' ';
3513                 }
3514         }
3515         return (res_str == NULL) ? inp : res_str;
3516 }
3517
3518 static char **make_list_in(char **inp, char *name)
3519 {
3520         int len, i;
3521         int name_len = strlen(name);
3522         int n = 0;
3523         char **list;
3524         char *p1, *p2, *p3;
3525
3526         /* create list of variable values */
3527         list = xmalloc(sizeof(*list));
3528         for (i = 0; inp[i]; i++) {
3529                 p3 = insert_var_value(inp[i]);
3530                 p1 = p3;
3531                 while (*p1) {
3532                         if ((*p1 == ' ')) {
3533                                 p1++;
3534                                 continue;
3535                         }
3536                         if ((p2 = strchr(p1, ' '))) {
3537                                 len = p2 - p1;
3538                         } else {
3539                                 len = strlen(p1);
3540                                 p2 = p1 + len;
3541                         }
3542                         /* we use n + 2 in realloc for list,because we add
3543                          * new element and then we will add NULL element */
3544                         list = xrealloc(list, sizeof(*list) * (n + 2));
3545                         list[n] = xmalloc(2 + name_len + len);
3546                         strcpy(list[n], name);
3547                         strcat(list[n], "=");
3548                         strncat(list[n], p1, len);
3549                         list[n++][name_len + len + 1] = '\0';
3550                         p1 = p2;
3551                 }
3552                 if (p3 != inp[i]) free(p3);
3553         }
3554         list[n] = NULL;
3555         return list;
3556 }
3557
3558 /* Make new string for parser */
3559 static char * make_string(char ** inp)
3560 {
3561         char *p;
3562         char *str = NULL;
3563         int n;
3564         int len = 2;
3565
3566         for (n = 0; inp[n]; n++) {
3567                 p = insert_var_value(inp[n]);
3568                 str = xrealloc(str, (len + strlen(p)));
3569                 if (n) {
3570                         strcat(str, " ");
3571                 } else {
3572                         *str = '\0';
3573                 }
3574                 strcat(str, p);
3575                 len = strlen(str) + 3;
3576                 if (p != inp[n]) free(p);
3577         }
3578         len = strlen(str);
3579         *(str + len) = '\n';
3580         *(str + len + 1) = '\0';
3581         return str;
3582 }
3583
3584 #ifdef __U_BOOT__
3585 int do_showvar (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
3586 {
3587         int i, k;
3588         int rcode = 0;
3589         struct variables *cur;
3590
3591         if (argc == 1) {                /* Print all env variables      */
3592                 for (cur = top_vars; cur; cur = cur->next) {
3593                         printf ("%s=%s\n", cur->name, cur->value);
3594                         if (ctrlc ()) {
3595                                 puts ("\n ** Abort\n");
3596                                 return 1;
3597                         }
3598                 }
3599                 return 0;
3600         }
3601         for (i = 1; i < argc; ++i) {    /* print single env variables   */
3602                 char *name = argv[i];
3603
3604                 k = -1;
3605                 for (cur = top_vars; cur; cur = cur->next) {
3606                         if(strcmp (cur->name, name) == 0) {
3607                                 k = 0;
3608                                 printf ("%s=%s\n", cur->name, cur->value);
3609                         }
3610                         if (ctrlc ()) {
3611                                 puts ("\n ** Abort\n");
3612                                 return 1;
3613                         }
3614                 }
3615                 if (k < 0) {
3616                         printf ("## Error: \"%s\" not defined\n", name);
3617                         rcode ++;
3618                 }
3619         }
3620         return rcode;
3621 }
3622
3623 U_BOOT_CMD(
3624         showvar, CONFIG_SYS_MAXARGS, 1, do_showvar,
3625         "print local hushshell variables",
3626         "\n    - print values of all hushshell variables\n"
3627         "showvar name ...\n"
3628         "    - print value of hushshell variable 'name'"
3629 );
3630
3631 #endif
3632 /****************************************************************************/