common/hush.c

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