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