common/cli_hush.c

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