git.sur5r.net Git - u-boot/blob - common/hush.c

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