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