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 <console.h>
  83 #include <bootretry.h>
  84 #include <cli.h>
  85 #include <cli_hush.h>
  86 #include <command.h>        /* find_cmd */
  87 #ifndef CONFIG_SYS_PROMPT_HUSH_PS2
  88 #define CONFIG_SYS_PROMPT_HUSH_PS2      "> "
  89 #endif
  90 #endif
  91 #ifndef __U_BOOT__
  92 #include <ctype.h>     /* isalpha, isdigit */
  93 #include <unistd.h>    /* getpid */
  94 #include <stdlib.h>    /* getenv, atoi */
  95 #include <string.h>    /* strchr */
  96 #include <stdio.h>     /* popen etc. */
  97 #include <glob.h>      /* glob, of course */
  98 #include <stdarg.h>    /* va_list */
  99 #include <errno.h>
 100 #include <fcntl.h>
 101 #include <getopt.h>    /* should be pretty obvious */
 102
 103 #include <sys/stat.h>  /* ulimit */
 104 #include <sys/types.h>
 105 #include <sys/wait.h>
 106 #include <signal.h>
 107
 108 /* #include <dmalloc.h> */
 109
 110 #if 1
 111 #include "busybox.h"
 112 #include "cmdedit.h"
 113 #else
 114 #define applet_name "hush"
 115 #include "standalone.h"
 116 #define hush_main main
 117 #undef CONFIG_FEATURE_SH_FANCY_PROMPT
 118 #define BB_BANNER
 119 #endif
 120 #endif
 121 #define SPECIAL_VAR_SYMBOL 03
 122 #define SUBSTED_VAR_SYMBOL 04
 123 #ifndef __U_BOOT__
 124 #define FLAG_EXIT_FROM_LOOP 1
 125 #define FLAG_PARSE_SEMICOLON (1 << 1)           /* symbol ';' is special for parser */
 126 #define FLAG_REPARSING       (1 << 2)           /* >= 2nd pass */
 127
 128 #endif
 129
 130 #ifdef __U_BOOT__
 131 DECLARE_GLOBAL_DATA_PTR;
 132
 133 #define EXIT_SUCCESS 0
 134 #define EOF -1
 135 #define syntax() syntax_err()
 136 #define xstrdup strdup
 137 #define error_msg printf
 138 #else
 139 typedef enum {
 140         REDIRECT_INPUT     = 1,
 141         REDIRECT_OVERWRITE = 2,
 142         REDIRECT_APPEND    = 3,
 143         REDIRECT_HEREIS    = 4,
 144         REDIRECT_IO        = 5
 145 } redir_type;
 146
 147 /* The descrip member of this structure is only used to make debugging
 148  * output pretty */
 149 struct {int mode; int default_fd; char *descrip;} redir_table[] = {
 150         { 0,                         0, "()" },
 151         { O_RDONLY,                  0, "<"  },
 152         { O_CREAT|O_TRUNC|O_WRONLY,  1, ">"  },
 153         { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
 154         { O_RDONLY,                 -1, "<<" },
 155         { O_RDWR,                    1, "<>" }
 156 };
 157 #endif
 158
 159 typedef enum {
 160         PIPE_SEQ = 1,
 161         PIPE_AND = 2,
 162         PIPE_OR  = 3,
 163         PIPE_BG  = 4,
 164 } pipe_style;
 165
 166 /* might eventually control execution */
 167 typedef enum {
 168         RES_NONE  = 0,
 169         RES_IF    = 1,
 170         RES_THEN  = 2,
 171         RES_ELIF  = 3,
 172         RES_ELSE  = 4,
 173         RES_FI    = 5,
 174         RES_FOR   = 6,
 175         RES_WHILE = 7,
 176         RES_UNTIL = 8,
 177         RES_DO    = 9,
 178         RES_DONE  = 10,
 179         RES_XXXX  = 11,
 180         RES_IN    = 12,
 181         RES_SNTX  = 13
 182 } reserved_style;
 183 #define FLAG_END   (1<<RES_NONE)
 184 #define FLAG_IF    (1<<RES_IF)
 185 #define FLAG_THEN  (1<<RES_THEN)
 186 #define FLAG_ELIF  (1<<RES_ELIF)
 187 #define FLAG_ELSE  (1<<RES_ELSE)
 188 #define FLAG_FI    (1<<RES_FI)
 189 #define FLAG_FOR   (1<<RES_FOR)
 190 #define FLAG_WHILE (1<<RES_WHILE)
 191 #define FLAG_UNTIL (1<<RES_UNTIL)
 192 #define FLAG_DO    (1<<RES_DO)
 193 #define FLAG_DONE  (1<<RES_DONE)
 194 #define FLAG_IN    (1<<RES_IN)
 195 #define FLAG_START (1<<RES_XXXX)
 196
 197 /* This holds pointers to the various results of parsing */
 198 struct p_context {
 199         struct child_prog *child;
 200         struct pipe *list_head;
 201         struct pipe *pipe;
 202 #ifndef __U_BOOT__
 203         struct redir_struct *pending_redirect;
 204 #endif
 205         reserved_style w;
 206         int old_flag;                           /* for figuring out valid reserved words */
 207         struct p_context *stack;
 208         int type;                       /* define type of parser : ";$" common or special symbol */
 209         /* How about quoting status? */
 210 };
 211
 212 #ifndef __U_BOOT__
 213 struct redir_struct {
 214         redir_type type;                        /* type of redirection */
 215         int fd;                                         /* file descriptor being redirected */
 216         int dup;                                        /* -1, or file descriptor being duplicated */
 217         struct redir_struct *next;      /* pointer to the next redirect in the list */
 218         glob_t word;                            /* *word.gl_pathv is the filename */
 219 };
 220 #endif
 221
 222 struct child_prog {
 223 #ifndef __U_BOOT__
 224         pid_t pid;                                      /* 0 if exited */
 225 #endif
 226         char **argv;                            /* program name and arguments */
 227         /* was quoted when parsed; copy of struct o_string.nonnull field */
 228         int *argv_nonnull;
 229 #ifdef __U_BOOT__
 230         int    argc;                            /* number of program arguments */
 231 #endif
 232         struct pipe *group;                     /* if non-NULL, first in group or subshell */
 233 #ifndef __U_BOOT__
 234         int subshell;                           /* flag, non-zero if group must be forked */
 235         struct redir_struct *redirects; /* I/O redirections */
 236         glob_t glob_result;                     /* result of parameter globbing */
 237         int is_stopped;                         /* is the program currently running? */
 238         struct pipe *family;            /* pointer back to the child's parent pipe */
 239 #endif
 240         int sp;                         /* number of SPECIAL_VAR_SYMBOL */
 241         int type;
 242 };
 243
 244 struct pipe {
 245 #ifndef __U_BOOT__
 246         int jobid;                                      /* job number */
 247 #endif
 248         int num_progs;                          /* total number of programs in job */
 249 #ifndef __U_BOOT__
 250         int running_progs;                      /* number of programs running */
 251         char *text;                                     /* name of job */
 252         char *cmdbuf;                           /* buffer various argv's point into */
 253         pid_t pgrp;                                     /* process group ID for the job */
 254 #endif
 255         struct child_prog *progs;       /* array of commands in pipe */
 256         struct pipe *next;                      /* to track background commands */
 257 #ifndef __U_BOOT__
 258         int stopped_progs;                      /* number of programs alive, but stopped */
 259         int job_context;                        /* bitmask defining current context */
 260 #endif
 261         pipe_style followup;            /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
 262         reserved_style r_mode;          /* supports if, for, while, until */
 263 };
 264
 265 #ifndef __U_BOOT__
 266 struct close_me {
 267         int fd;
 268         struct close_me *next;
 269 };
 270 #endif
 271
 272 struct variables {
 273         char *name;
 274         char *value;
 275         int flg_export;
 276         int flg_read_only;
 277         struct variables *next;
 278 };
 279
 280 /* globals, connect us to the outside world
 281  * the first three support $?, $#, and $1 */
 282 #ifndef __U_BOOT__
 283 char **global_argv;
 284 unsigned int global_argc;
 285 #endif
 286 static unsigned int last_return_code;
 287 #ifndef __U_BOOT__
 288 extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
 289 #endif
 290
 291 /* "globals" within this file */
 292 static uchar *ifs;
 293 static char map[256];
 294 #ifndef __U_BOOT__
 295 static int fake_mode;
 296 static int interactive;
 297 static struct close_me *close_me_head;
 298 static const char *cwd;
 299 static struct pipe *job_list;
 300 static unsigned int last_bg_pid;
 301 static unsigned int last_jobid;
 302 static unsigned int shell_terminal;
 303 static char *PS1;
 304 static char *PS2;
 305 struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
 306 struct variables *top_vars = &shell_ver;
 307 #else
 308 static int flag_repeat = 0;
 309 static int do_repeat = 0;
 310 static struct variables *top_vars = NULL ;
 311 #endif /*__U_BOOT__ */
 312
 313 #define B_CHUNK (100)
 314 #define B_NOSPAC 1
 315
 316 typedef struct {
 317         char *data;
 318         int length;
 319         int maxlen;
 320         int quote;
 321         int nonnull;
 322 } o_string;
 323 #define NULL_O_STRING {NULL,0,0,0,0}
 324 /* used for initialization:
 325         o_string foo = NULL_O_STRING; */
 326
 327 /* I can almost use ordinary FILE *.  Is open_memstream() universally
 328  * available?  Where is it documented? */
 329 struct in_str {
 330         const char *p;
 331 #ifndef __U_BOOT__
 332         char peek_buf[2];
 333 #endif
 334         int __promptme;
 335         int promptmode;
 336 #ifndef __U_BOOT__
 337         FILE *file;
 338 #endif
 339         int (*get) (struct in_str *);
 340         int (*peek) (struct in_str *);
 341 };
 342 #define b_getch(input) ((input)->get(input))
 343 #define b_peek(input) ((input)->peek(input))
 344
 345 #ifndef __U_BOOT__
 346 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
 347
 348 struct built_in_command {
 349         char *cmd;                                      /* name */
 350         char *descr;                            /* description */
 351         int (*function) (struct child_prog *);  /* function ptr */
 352 };
 353 #endif
 354
 355 /* define DEBUG_SHELL for debugging output (obviously ;-)) */
 356 #if 0
 357 #define DEBUG_SHELL
 358 #endif
 359
 360 /* This should be in utility.c */
 361 #ifdef DEBUG_SHELL
 362 #ifndef __U_BOOT__
 363 static void debug_printf(const char *format, ...)
 364 {
 365         va_list args;
 366         va_start(args, format);
 367         vfprintf(stderr, format, args);
 368         va_end(args);
 369 }
 370 #else
 371 #define debug_printf(fmt,args...)       printf (fmt ,##args)
 372 #endif
 373 #else
 374 static inline void debug_printf(const char *format, ...) { }
 375 #endif
 376 #define final_printf debug_printf
 377
 378 #ifdef __U_BOOT__
 379 static void syntax_err(void) {
 380          printf("syntax error\n");
 381 }
 382 #else
 383 static void __syntax(char *file, int line) {
 384         error_msg("syntax error %s:%d", file, line);
 385 }
 386 #define syntax() __syntax(__FILE__, __LINE__)
 387 #endif
 388
 389 #ifdef __U_BOOT__
 390 static void *xmalloc(size_t size);
 391 static void *xrealloc(void *ptr, size_t size);
 392 #else
 393 /* Index of subroutines: */
 394 /*   function prototypes for builtins */
 395 static int builtin_cd(struct child_prog *child);
 396 static int builtin_env(struct child_prog *child);
 397 static int builtin_eval(struct child_prog *child);
 398 static int builtin_exec(struct child_prog *child);
 399 static int builtin_exit(struct child_prog *child);
 400 static int builtin_export(struct child_prog *child);
 401 static int builtin_fg_bg(struct child_prog *child);
 402 static int builtin_help(struct child_prog *child);
 403 static int builtin_jobs(struct child_prog *child);
 404 static int builtin_pwd(struct child_prog *child);
 405 static int builtin_read(struct child_prog *child);
 406 static int builtin_set(struct child_prog *child);
 407 static int builtin_shift(struct child_prog *child);
 408 static int builtin_source(struct child_prog *child);
 409 static int builtin_umask(struct child_prog *child);
 410 static int builtin_unset(struct child_prog *child);
 411 static int builtin_not_written(struct child_prog *child);
 412 #endif
 413 /*   o_string manipulation: */
 414 static int b_check_space(o_string *o, int len);
 415 static int b_addchr(o_string *o, int ch);
 416 static void b_reset(o_string *o);
 417 static int b_addqchr(o_string *o, int ch, int quote);
 418 #ifndef __U_BOOT__
 419 static int b_adduint(o_string *o, unsigned int i);
 420 #endif
 421 /*  in_str manipulations: */
 422 static int static_get(struct in_str *i);
 423 static int static_peek(struct in_str *i);
 424 static int file_get(struct in_str *i);
 425 static int file_peek(struct in_str *i);
 426 #ifndef __U_BOOT__
 427 static void setup_file_in_str(struct in_str *i, FILE *f);
 428 #else
 429 static void setup_file_in_str(struct in_str *i);
 430 #endif
 431 static void setup_string_in_str(struct in_str *i, const char *s);
 432 #ifndef __U_BOOT__
 433 /*  close_me manipulations: */
 434 static void mark_open(int fd);
 435 static void mark_closed(int fd);
 436 static void close_all(void);
 437 #endif
 438 /*  "run" the final data structures: */
 439 static char *indenter(int i);
 440 static int free_pipe_list(struct pipe *head, int indent);
 441 static int free_pipe(struct pipe *pi, int indent);
 442 /*  really run the final data structures: */
 443 #ifndef __U_BOOT__
 444 static int setup_redirects(struct child_prog *prog, int squirrel[]);
 445 #endif
 446 static int run_list_real(struct pipe *pi);
 447 #ifndef __U_BOOT__
 448 static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
 449 #endif
 450 static int run_pipe_real(struct pipe *pi);
 451 /*   extended glob support: */
 452 #ifndef __U_BOOT__
 453 static int globhack(const char *src, int flags, glob_t *pglob);
 454 static int glob_needed(const char *s);
 455 static int xglob(o_string *dest, int flags, glob_t *pglob);
 456 #endif
 457 /*   variable assignment: */
 458 static int is_assignment(const char *s);
 459 /*   data structure manipulation: */
 460 #ifndef __U_BOOT__
 461 static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
 462 #endif
 463 static void initialize_context(struct p_context *ctx);
 464 static int done_word(o_string *dest, struct p_context *ctx);
 465 static int done_command(struct p_context *ctx);
 466 static int done_pipe(struct p_context *ctx, pipe_style type);
 467 /*   primary string parsing: */
 468 #ifndef __U_BOOT__
 469 static int redirect_dup_num(struct in_str *input);
 470 static int redirect_opt_num(o_string *o);
 471 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
 472 static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
 473 #endif
 474 static char *lookup_param(char *src);
 475 static char *make_string(char **inp, int *nonnull);
 476 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
 477 #ifndef __U_BOOT__
 478 static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
 479 #endif
 480 static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
 481 /*   setup: */
 482 static int parse_stream_outer(struct in_str *inp, int flag);
 483 #ifndef __U_BOOT__
 484 static int parse_string_outer(const char *s, int flag);
 485 static int parse_file_outer(FILE *f);
 486 #endif
 487 #ifndef __U_BOOT__
 488 /*   job management: */
 489 static int checkjobs(struct pipe* fg_pipe);
 490 static void insert_bg_job(struct pipe *pi);
 491 static void remove_bg_job(struct pipe *pi);
 492 #endif
 493 /*     local variable support */
 494 static char **make_list_in(char **inp, char *name);
 495 static char *insert_var_value(char *inp);
 496 static char *insert_var_value_sub(char *inp, int tag_subst);
 497
 498 #ifndef __U_BOOT__
 499 /* Table of built-in functions.  They can be forked or not, depending on
 500  * context: within pipes, they fork.  As simple commands, they do not.
 501  * When used in non-forking context, they can change global variables
 502  * in the parent shell process.  If forked, of course they can not.
 503  * For example, 'unset foo | whatever' will parse and run, but foo will
 504  * still be set at the end. */
 505 static struct built_in_command bltins[] = {
 506         {"bg", "Resume a job in the background", builtin_fg_bg},
 507         {"break", "Exit for, while or until loop", builtin_not_written},
 508         {"cd", "Change working directory", builtin_cd},
 509         {"continue", "Continue for, while or until loop", builtin_not_written},
 510         {"env", "Print all environment variables", builtin_env},
 511         {"eval", "Construct and run shell command", builtin_eval},
 512         {"exec", "Exec command, replacing this shell with the exec'd process",
 513                 builtin_exec},
 514         {"exit", "Exit from shell()", builtin_exit},
 515         {"export", "Set environment variable", builtin_export},
 516         {"fg", "Bring job into the foreground", builtin_fg_bg},
 517         {"jobs", "Lists the active jobs", builtin_jobs},
 518         {"pwd", "Print current directory", builtin_pwd},
 519         {"read", "Input environment variable", builtin_read},
 520         {"return", "Return from a function", builtin_not_written},
 521         {"set", "Set/unset shell local variables", builtin_set},
 522         {"shift", "Shift positional parameters", builtin_shift},
 523         {"trap", "Trap signals", builtin_not_written},
 524         {"ulimit","Controls resource limits", builtin_not_written},
 525         {"umask","Sets file creation mask", builtin_umask},
 526         {"unset", "Unset environment variable", builtin_unset},
 527         {".", "Source-in and run commands in a file", builtin_source},
 528         {"help", "List shell built-in commands", builtin_help},
 529         {NULL, NULL, NULL}
 530 };
 531
 532 static const char *set_cwd(void)
 533 {
 534         if(cwd==unknown)
 535                 cwd = NULL;     /* xgetcwd(arg) called free(arg) */
 536         cwd = xgetcwd((char *)cwd);
 537         if (!cwd)
 538                 cwd = unknown;
 539         return cwd;
 540 }
 541
 542 /* built-in 'eval' handler */
 543 static int builtin_eval(struct child_prog *child)
 544 {
 545         char *str = NULL;
 546         int rcode = EXIT_SUCCESS;
 547
 548         if (child->argv[1]) {
 549                 str = make_string(child->argv + 1);
 550                 parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
 551                                         FLAG_PARSE_SEMICOLON);
 552                 free(str);
 553                 rcode = last_return_code;
 554         }
 555         return rcode;
 556 }
 557
 558 /* built-in 'cd <path>' handler */
 559 static int builtin_cd(struct child_prog *child)
 560 {
 561         char *newdir;
 562         if (child->argv[1] == NULL)
 563                 newdir = getenv("HOME");
 564         else
 565                 newdir = child->argv[1];
 566         if (chdir(newdir)) {
 567                 printf("cd: %s: %s\n", newdir, strerror(errno));
 568                 return EXIT_FAILURE;
 569         }
 570         set_cwd();
 571         return EXIT_SUCCESS;
 572 }
 573
 574 /* built-in 'env' handler */
 575 static int builtin_env(struct child_prog *dummy)
 576 {
 577         char **e = environ;
 578         if (e == NULL) return EXIT_FAILURE;
 579         for (; *e; e++) {
 580                 puts(*e);
 581         }
 582         return EXIT_SUCCESS;
 583 }
 584
 585 /* built-in 'exec' handler */
 586 static int builtin_exec(struct child_prog *child)
 587 {
 588         if (child->argv[1] == NULL)
 589                 return EXIT_SUCCESS;   /* Really? */
 590         child->argv++;
 591         pseudo_exec(child);
 592         /* never returns */
 593 }
 594
 595 /* built-in 'exit' handler */
 596 static int builtin_exit(struct child_prog *child)
 597 {
 598         if (child->argv[1] == NULL)
 599                 exit(last_return_code);
 600         exit (atoi(child->argv[1]));
 601 }
 602
 603 /* built-in 'export VAR=value' handler */
 604 static int builtin_export(struct child_prog *child)
 605 {
 606         int res = 0;
 607         char *name = child->argv[1];
 608
 609         if (name == NULL) {
 610                 return (builtin_env(child));
 611         }
 612
 613         name = strdup(name);
 614
 615         if(name) {
 616                 char *value = strchr(name, '=');
 617
 618                 if (!value) {
 619                         char *tmp;
 620                         /* They are exporting something without an =VALUE */
 621
 622                         value = get_local_var(name);
 623                         if (value) {
 624                                 size_t ln = strlen(name);
 625
 626                                 tmp = realloc(name, ln+strlen(value)+2);
 627                                 if(tmp==NULL)
 628                                         res = -1;
 629                                 else {
 630                                         sprintf(tmp+ln, "=%s", value);
 631                                         name = tmp;
 632                                 }
 633                         } else {
 634                                 /* bash does not return an error when trying to export
 635                                  * an undefined variable.  Do likewise. */
 636                                 res = 1;
 637                         }
 638                 }
 639         }
 640         if (res<0)
 641                 perror_msg("export");
 642         else if(res==0)
 643                 res = set_local_var(name, 1);
 644         else
 645                 res = 0;
 646         free(name);
 647         return res;
 648 }
 649
 650 /* built-in 'fg' and 'bg' handler */
 651 static int builtin_fg_bg(struct child_prog *child)
 652 {
 653         int i, jobnum;
 654         struct pipe *pi=NULL;
 655
 656         if (!interactive)
 657                 return EXIT_FAILURE;
 658         /* If they gave us no args, assume they want the last backgrounded task */
 659         if (!child->argv[1]) {
 660                 for (pi = job_list; pi; pi = pi->next) {
 661                         if (pi->jobid == last_jobid) {
 662                                 break;
 663                         }
 664                 }
 665                 if (!pi) {
 666                         error_msg("%s: no current job", child->argv[0]);
 667                         return EXIT_FAILURE;
 668                 }
 669         } else {
 670                 if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
 671                         error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
 672                         return EXIT_FAILURE;
 673                 }
 674                 for (pi = job_list; pi; pi = pi->next) {
 675                         if (pi->jobid == jobnum) {
 676                                 break;
 677                         }
 678                 }
 679                 if (!pi) {
 680                         error_msg("%s: %d: no such job", child->argv[0], jobnum);
 681                         return EXIT_FAILURE;
 682                 }
 683         }
 684
 685         if (*child->argv[0] == 'f') {
 686                 /* Put the job into the foreground.  */
 687                 tcsetpgrp(shell_terminal, pi->pgrp);
 688         }
 689
 690         /* Restart the processes in the job */
 691         for (i = 0; i < pi->num_progs; i++)
 692                 pi->progs[i].is_stopped = 0;
 693
 694         if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) {
 695                 if (i == ESRCH) {
 696                         remove_bg_job(pi);
 697                 } else {
 698                         perror_msg("kill (SIGCONT)");
 699                 }
 700         }
 701
 702         pi->stopped_progs = 0;
 703         return EXIT_SUCCESS;
 704 }
 705
 706 /* built-in 'help' handler */
 707 static int builtin_help(struct child_prog *dummy)
 708 {
 709         struct built_in_command *x;
 710
 711         printf("\nBuilt-in commands:\n");
 712         printf("-------------------\n");
 713         for (x = bltins; x->cmd; x++) {
 714                 if (x->descr==NULL)
 715                         continue;
 716                 printf("%s\t%s\n", x->cmd, x->descr);
 717         }
 718         printf("\n\n");
 719         return EXIT_SUCCESS;
 720 }
 721
 722 /* built-in 'jobs' handler */
 723 static int builtin_jobs(struct child_prog *child)
 724 {
 725         struct pipe *job;
 726         char *status_string;
 727
 728         for (job = job_list; job; job = job->next) {
 729                 if (job->running_progs == job->stopped_progs)
 730                         status_string = "Stopped";
 731                 else
 732                         status_string = "Running";
 733
 734                 printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
 735         }
 736         return EXIT_SUCCESS;
 737 }
 738
 739
 740 /* built-in 'pwd' handler */
 741 static int builtin_pwd(struct child_prog *dummy)
 742 {
 743         puts(set_cwd());
 744         return EXIT_SUCCESS;
 745 }
 746
 747 /* built-in 'read VAR' handler */
 748 static int builtin_read(struct child_prog *child)
 749 {
 750         int res;
 751
 752         if (child->argv[1]) {
 753                 char string[BUFSIZ];
 754                 char *var = 0;
 755
 756                 string[0] = 0;  /* In case stdin has only EOF */
 757                 /* read string */
 758                 fgets(string, sizeof(string), stdin);
 759                 chomp(string);
 760                 var = malloc(strlen(child->argv[1])+strlen(string)+2);
 761                 if(var) {
 762                         sprintf(var, "%s=%s", child->argv[1], string);
 763                         res = set_local_var(var, 0);
 764                 } else
 765                         res = -1;
 766                 if (res)
 767                         fprintf(stderr, "read: %m\n");
 768                 free(var);      /* So not move up to avoid breaking errno */
 769                 return res;
 770         } else {
 771                 do res=getchar(); while(res!='\n' && res!=EOF);
 772                 return 0;
 773         }
 774 }
 775
 776 /* built-in 'set VAR=value' handler */
 777 static int builtin_set(struct child_prog *child)
 778 {
 779         char *temp = child->argv[1];
 780         struct variables *e;
 781
 782         if (temp == NULL)
 783                 for(e = top_vars; e; e=e->next)
 784                         printf("%s=%s\n", e->name, e->value);
 785         else
 786                 set_local_var(temp, 0);
 787
 788                 return EXIT_SUCCESS;
 789 }
 790
 791
 792 /* Built-in 'shift' handler */
 793 static int builtin_shift(struct child_prog *child)
 794 {
 795         int n=1;
 796         if (child->argv[1]) {
 797                 n=atoi(child->argv[1]);
 798         }
 799         if (n>=0 && n<global_argc) {
 800                 /* XXX This probably breaks $0 */
 801                 global_argc -= n;
 802                 global_argv += n;
 803                 return EXIT_SUCCESS;
 804         } else {
 805                 return EXIT_FAILURE;
 806         }
 807 }
 808
 809 /* Built-in '.' handler (read-in and execute commands from file) */
 810 static int builtin_source(struct child_prog *child)
 811 {
 812         FILE *input;
 813         int status;
 814
 815         if (child->argv[1] == NULL)
 816                 return EXIT_FAILURE;
 817
 818         /* XXX search through $PATH is missing */
 819         input = fopen(child->argv[1], "r");
 820         if (!input) {
 821                 error_msg("Couldn't open file '%s'", child->argv[1]);
 822                 return EXIT_FAILURE;
 823         }
 824
 825         /* Now run the file */
 826         /* XXX argv and argc are broken; need to save old global_argv
 827          * (pointer only is OK!) on this stack frame,
 828          * set global_argv=child->argv+1, recurse, and restore. */
 829         mark_open(fileno(input));
 830         status = parse_file_outer(input);
 831         mark_closed(fileno(input));
 832         fclose(input);
 833         return (status);
 834 }
 835
 836 static int builtin_umask(struct child_prog *child)
 837 {
 838         mode_t new_umask;
 839         const char *arg = child->argv[1];
 840         char *end;
 841         if (arg) {
 842                 new_umask=strtoul(arg, &end, 8);
 843                 if (*end!='\0' || end == arg) {
 844                         return EXIT_FAILURE;
 845                 }
 846         } else {
 847                 printf("%.3o\n", (unsigned int) (new_umask=umask(0)));
 848         }
 849         umask(new_umask);
 850         return EXIT_SUCCESS;
 851 }
 852
 853 /* built-in 'unset VAR' handler */
 854 static int builtin_unset(struct child_prog *child)
 855 {
 856         /* bash returned already true */
 857         unset_local_var(child->argv[1]);
 858         return EXIT_SUCCESS;
 859 }
 860
 861 static int builtin_not_written(struct child_prog *child)
 862 {
 863         printf("builtin_%s not written\n",child->argv[0]);
 864         return EXIT_FAILURE;
 865 }
 866 #endif
 867
 868 static int b_check_space(o_string *o, int len)
 869 {
 870         /* It would be easy to drop a more restrictive policy
 871          * in here, such as setting a maximum string length */
 872         if (o->length + len > o->maxlen) {
 873                 char *old_data = o->data;
 874                 /* assert (data == NULL || o->maxlen != 0); */
 875                 o->maxlen += max(2*len, B_CHUNK);
 876                 o->data = realloc(o->data, 1 + o->maxlen);
 877                 if (o->data == NULL) {
 878                         free(old_data);
 879                 }
 880         }
 881         return o->data == NULL;
 882 }
 883
 884 static int b_addchr(o_string *o, int ch)
 885 {
 886         debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
 887         if (b_check_space(o, 1)) return B_NOSPAC;
 888         o->data[o->length] = ch;
 889         o->length++;
 890         o->data[o->length] = '\0';
 891         return 0;
 892 }
 893
 894 static void b_reset(o_string *o)
 895 {
 896         o->length = 0;
 897         o->nonnull = 0;
 898         if (o->data != NULL) *o->data = '\0';
 899 }
 900
 901 static void b_free(o_string *o)
 902 {
 903         b_reset(o);
 904         free(o->data);
 905         o->data = NULL;
 906         o->maxlen = 0;
 907 }
 908
 909 /* My analysis of quoting semantics tells me that state information
 910  * is associated with a destination, not a source.
 911  */
 912 static int b_addqchr(o_string *o, int ch, int quote)
 913 {
 914         if (quote && strchr("*?[\\",ch)) {
 915                 int rc;
 916                 rc = b_addchr(o, '\\');
 917                 if (rc) return rc;
 918         }
 919         return b_addchr(o, ch);
 920 }
 921
 922 #ifndef __U_BOOT__
 923 static int b_adduint(o_string *o, unsigned int i)
 924 {
 925         int r;
 926         char *p = simple_itoa(i);
 927         /* no escape checking necessary */
 928         do r=b_addchr(o, *p++); while (r==0 && *p);
 929         return r;
 930 }
 931 #endif
 932
 933 static int static_get(struct in_str *i)
 934 {
 935         int ch = *i->p++;
 936         if (ch=='\0') return EOF;
 937         return ch;
 938 }
 939
 940 static int static_peek(struct in_str *i)
 941 {
 942         return *i->p;
 943 }
 944
 945 #ifndef __U_BOOT__
 946 static inline void cmdedit_set_initial_prompt(void)
 947 {
 948 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
 949         PS1 = NULL;
 950 #else
 951         PS1 = getenv("PS1");
 952         if(PS1==0)
 953                 PS1 = "\\w \\$ ";
 954 #endif
 955 }
 956
 957 static inline void setup_prompt_string(int promptmode, char **prompt_str)
 958 {
 959         debug_printf("setup_prompt_string %d ",promptmode);
 960 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
 961         /* Set up the prompt */
 962         if (promptmode == 1) {
 963                 free(PS1);
 964                 PS1=xmalloc(strlen(cwd)+4);
 965                 sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ?  "$ ":"# ");
 966                 *prompt_str = PS1;
 967         } else {
 968                 *prompt_str = PS2;
 969         }
 970 #else
 971         *prompt_str = (promptmode==1)? PS1 : PS2;
 972 #endif
 973         debug_printf("result %s\n",*prompt_str);
 974 }
 975 #endif
 976
 977 #ifdef __U_BOOT__
 978 static int uboot_cli_readline(struct in_str *i)
 979 {
 980         char *prompt;
 981
 982         if (i->promptmode == 1)
 983                 prompt = CONFIG_SYS_PROMPT;
 984         else
 985                 prompt = CONFIG_SYS_PROMPT_HUSH_PS2;
 986
 987         return cli_readline(prompt);
 988 }
 989 #endif
 990
 991 static void get_user_input(struct in_str *i)
 992 {
 993 #ifndef __U_BOOT__
 994         char *prompt_str;
 995         static char the_command[BUFSIZ];
 996
 997         setup_prompt_string(i->promptmode, &prompt_str);
 998 #ifdef CONFIG_FEATURE_COMMAND_EDITING
 999         /*
1000          ** enable command line editing only while a command line
1001          ** is actually being read; otherwise, we'll end up bequeathing
1002          ** atexit() handlers and other unwanted stuff to our
1003          ** child processes (rob@sysgo.de)
1004          */
1005         cmdedit_read_input(prompt_str, the_command);
1006 #else
1007         fputs(prompt_str, stdout);
1008         fflush(stdout);
1009         the_command[0]=fgetc(i->file);
1010         the_command[1]='\0';
1011 #endif
1012         fflush(stdout);
1013         i->p = the_command;
1014 #else
1015         int n;
1016         static char the_command[CONFIG_SYS_CBSIZE + 1];
1017
1018         bootretry_reset_cmd_timeout();
1019         i->__promptme = 1;
1020         n = uboot_cli_readline(i);
1021
1022 #ifdef CONFIG_BOOT_RETRY_TIME
1023         if (n == -2) {
1024           puts("\nTimeout waiting for command\n");
1025 #  ifdef CONFIG_RESET_TO_RETRY
1026           do_reset(NULL, 0, 0, NULL);
1027 #  else
1028 #       error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1029 #  endif
1030         }
1031 #endif
1032         if (n == -1 ) {
1033                 flag_repeat = 0;
1034                 i->__promptme = 0;
1035         }
1036         n = strlen(console_buffer);
1037         console_buffer[n] = '\n';
1038         console_buffer[n+1]= '\0';
1039         if (had_ctrlc()) flag_repeat = 0;
1040         clear_ctrlc();
1041         do_repeat = 0;
1042         if (i->promptmode == 1) {
1043                 if (console_buffer[0] == '\n'&& flag_repeat == 0) {
1044                         strcpy(the_command,console_buffer);
1045                 }
1046                 else {
1047                         if (console_buffer[0] != '\n') {
1048                                 strcpy(the_command,console_buffer);
1049                                 flag_repeat = 1;
1050                         }
1051                         else {
1052                                 do_repeat = 1;
1053                         }
1054                 }
1055                 i->p = the_command;
1056         }
1057         else {
1058                 if (console_buffer[0] != '\n') {
1059                         if (strlen(the_command) + strlen(console_buffer)
1060                             < CONFIG_SYS_CBSIZE) {
1061                                 n = strlen(the_command);
1062                                 the_command[n-1] = ' ';
1063                                 strcpy(&the_command[n],console_buffer);
1064                         }
1065                         else {
1066                                 the_command[0] = '\n';
1067                                 the_command[1] = '\0';
1068                                 flag_repeat = 0;
1069                         }
1070                 }
1071                 if (i->__promptme == 0) {
1072                         the_command[0] = '\n';
1073                         the_command[1] = '\0';
1074                 }
1075                 i->p = console_buffer;
1076         }
1077 #endif
1078 }
1079
1080 /* This is the magic location that prints prompts
1081  * and gets data back from the user */
1082 static int file_get(struct in_str *i)
1083 {
1084         int ch;
1085
1086         ch = 0;
1087         /* If there is data waiting, eat it up */
1088         if (i->p && *i->p) {
1089                 ch = *i->p++;
1090         } else {
1091                 /* need to double check i->file because we might be doing something
1092                  * more complicated by now, like sourcing or substituting. */
1093 #ifndef __U_BOOT__
1094                 if (i->__promptme && interactive && i->file == stdin) {
1095                         while(! i->p || (interactive && strlen(i->p)==0) ) {
1096 #else
1097                         while(! i->p  || strlen(i->p)==0 ) {
1098 #endif
1099                                 get_user_input(i);
1100                         }
1101                         i->promptmode=2;
1102 #ifndef __U_BOOT__
1103                         i->__promptme = 0;
1104 #endif
1105                         if (i->p && *i->p) {
1106                                 ch = *i->p++;
1107                         }
1108 #ifndef __U_BOOT__
1109                 } else {
1110                         ch = fgetc(i->file);
1111                 }
1112
1113 #endif
1114                 debug_printf("b_getch: got a %d\n", ch);
1115         }
1116 #ifndef __U_BOOT__
1117         if (ch == '\n') i->__promptme=1;
1118 #endif
1119         return ch;
1120 }
1121
1122 /* All the callers guarantee this routine will never be
1123  * used right after a newline, so prompting is not needed.
1124  */
1125 static int file_peek(struct in_str *i)
1126 {
1127 #ifndef __U_BOOT__
1128         if (i->p && *i->p) {
1129 #endif
1130                 return *i->p;
1131 #ifndef __U_BOOT__
1132         } else {
1133                 i->peek_buf[0] = fgetc(i->file);
1134                 i->peek_buf[1] = '\0';
1135                 i->p = i->peek_buf;
1136                 debug_printf("b_peek: got a %d\n", *i->p);
1137                 return *i->p;
1138         }
1139 #endif
1140 }
1141
1142 #ifndef __U_BOOT__
1143 static void setup_file_in_str(struct in_str *i, FILE *f)
1144 #else
1145 static void setup_file_in_str(struct in_str *i)
1146 #endif
1147 {
1148         i->peek = file_peek;
1149         i->get = file_get;
1150         i->__promptme=1;
1151         i->promptmode=1;
1152 #ifndef __U_BOOT__
1153         i->file = f;
1154 #endif
1155         i->p = NULL;
1156 }
1157
1158 static void setup_string_in_str(struct in_str *i, const char *s)
1159 {
1160         i->peek = static_peek;
1161         i->get = static_get;
1162         i->__promptme=1;
1163         i->promptmode=1;
1164         i->p = s;
1165 }
1166
1167 #ifndef __U_BOOT__
1168 static void mark_open(int fd)
1169 {
1170         struct close_me *new = xmalloc(sizeof(struct close_me));
1171         new->fd = fd;
1172         new->next = close_me_head;
1173         close_me_head = new;
1174 }
1175
1176 static void mark_closed(int fd)
1177 {
1178         struct close_me *tmp;
1179         if (close_me_head == NULL || close_me_head->fd != fd)
1180                 error_msg_and_die("corrupt close_me");
1181         tmp = close_me_head;
1182         close_me_head = close_me_head->next;
1183         free(tmp);
1184 }
1185
1186 static void close_all(void)
1187 {
1188         struct close_me *c;
1189         for (c=close_me_head; c; c=c->next) {
1190                 close(c->fd);
1191         }
1192         close_me_head = NULL;
1193 }
1194
1195 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1196  * and stderr if they are redirected. */
1197 static int setup_redirects(struct child_prog *prog, int squirrel[])
1198 {
1199         int openfd, mode;
1200         struct redir_struct *redir;
1201
1202         for (redir=prog->redirects; redir; redir=redir->next) {
1203                 if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1204                         /* something went wrong in the parse.  Pretend it didn't happen */
1205                         continue;
1206                 }
1207                 if (redir->dup == -1) {
1208                         mode=redir_table[redir->type].mode;
1209                         openfd = open(redir->word.gl_pathv[0], mode, 0666);
1210                         if (openfd < 0) {
1211                         /* this could get lost if stderr has been redirected, but
1212                            bash and ash both lose it as well (though zsh doesn't!) */
1213                                 perror_msg("error opening %s", redir->word.gl_pathv[0]);
1214                                 return 1;
1215                         }
1216                 } else {
1217                         openfd = redir->dup;
1218                 }
1219
1220                 if (openfd != redir->fd) {
1221                         if (squirrel && redir->fd < 3) {
1222                                 squirrel[redir->fd] = dup(redir->fd);
1223                         }
1224                         if (openfd == -3) {
1225                                 close(openfd);
1226                         } else {
1227                                 dup2(openfd, redir->fd);
1228                                 if (redir->dup == -1)
1229                                         close (openfd);
1230                         }
1231                 }
1232         }
1233         return 0;
1234 }
1235
1236 static void restore_redirects(int squirrel[])
1237 {
1238         int i, fd;
1239         for (i=0; i<3; i++) {
1240                 fd = squirrel[i];
1241                 if (fd != -1) {
1242                         /* No error checking.  I sure wouldn't know what
1243                          * to do with an error if I found one! */
1244                         dup2(fd, i);
1245                         close(fd);
1246                 }
1247         }
1248 }
1249
1250 /* never returns */
1251 /* XXX no exit() here.  If you don't exec, use _exit instead.
1252  * The at_exit handlers apparently confuse the calling process,
1253  * in particular stdin handling.  Not sure why? */
1254 static void pseudo_exec(struct child_prog *child)
1255 {
1256         int i, rcode;
1257         char *p;
1258         struct built_in_command *x;
1259         if (child->argv) {
1260                 for (i=0; is_assignment(child->argv[i]); i++) {
1261                         debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
1262                         p = insert_var_value(child->argv[i]);
1263                         putenv(strdup(p));
1264                         if (p != child->argv[i]) free(p);
1265                 }
1266                 child->argv+=i;  /* XXX this hack isn't so horrible, since we are about
1267                                         to exit, and therefore don't need to keep data
1268                                         structures consistent for free() use. */
1269                 /* If a variable is assigned in a forest, and nobody listens,
1270                  * was it ever really set?
1271                  */
1272                 if (child->argv[0] == NULL) {
1273                         _exit(EXIT_SUCCESS);
1274                 }
1275
1276                 /*
1277                  * Check if the command matches any of the builtins.
1278                  * Depending on context, this might be redundant.  But it's
1279                  * easier to waste a few CPU cycles than it is to figure out
1280                  * if this is one of those cases.
1281                  */
1282                 for (x = bltins; x->cmd; x++) {
1283                         if (strcmp(child->argv[0], x->cmd) == 0 ) {
1284                                 debug_printf("builtin exec %s\n", child->argv[0]);
1285                                 rcode = x->function(child);
1286                                 fflush(stdout);
1287                                 _exit(rcode);
1288                         }
1289                 }
1290
1291                 /* Check if the command matches any busybox internal commands
1292                  * ("applets") here.
1293                  * FIXME: This feature is not 100% safe, since
1294                  * BusyBox is not fully reentrant, so we have no guarantee the things
1295                  * from the .bss are still zeroed, or that things from .data are still
1296                  * at their defaults.  We could exec ourself from /proc/self/exe, but I
1297                  * really dislike relying on /proc for things.  We could exec ourself
1298                  * from global_argv[0], but if we are in a chroot, we may not be able
1299                  * to find ourself... */
1300 #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1301                 {
1302                         int argc_l;
1303                         char** argv_l=child->argv;
1304                         char *name = child->argv[0];
1305
1306 #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
1307                         /* Following discussions from November 2000 on the busybox mailing
1308                          * list, the default configuration, (without
1309                          * get_last_path_component()) lets the user force use of an
1310                          * external command by specifying the full (with slashes) filename.
1311                          * If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN then applets
1312                          * _aways_ override external commands, so if you want to run
1313                          * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the
1314                          * filesystem and is _not_ busybox.  Some systems may want this,
1315                          * most do not.  */
1316                         name = get_last_path_component(name);
1317 #endif
1318                         /* Count argc for use in a second... */
1319                         for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
1320                         optind = 1;
1321                         debug_printf("running applet %s\n", name);
1322                         run_applet_by_name(name, argc_l, child->argv);
1323                 }
1324 #endif
1325                 debug_printf("exec of %s\n",child->argv[0]);
1326                 execvp(child->argv[0],child->argv);
1327                 perror_msg("couldn't exec: %s",child->argv[0]);
1328                 _exit(1);
1329         } else if (child->group) {
1330                 debug_printf("runtime nesting to group\n");
1331                 interactive=0;    /* crucial!!!! */
1332                 rcode = run_list_real(child->group);
1333                 /* OK to leak memory by not calling free_pipe_list,
1334                  * since this process is about to exit */
1335                 _exit(rcode);
1336         } else {
1337                 /* Can happen.  See what bash does with ">foo" by itself. */
1338                 debug_printf("trying to pseudo_exec null command\n");
1339                 _exit(EXIT_SUCCESS);
1340         }
1341 }
1342
1343 static void insert_bg_job(struct pipe *pi)
1344 {
1345         struct pipe *thejob;
1346
1347         /* Linear search for the ID of the job to use */
1348         pi->jobid = 1;
1349         for (thejob = job_list; thejob; thejob = thejob->next)
1350                 if (thejob->jobid >= pi->jobid)
1351                         pi->jobid = thejob->jobid + 1;
1352
1353         /* add thejob to the list of running jobs */
1354         if (!job_list) {
1355                 thejob = job_list = xmalloc(sizeof(*thejob));
1356         } else {
1357                 for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
1358                 thejob->next = xmalloc(sizeof(*thejob));
1359                 thejob = thejob->next;
1360         }
1361
1362         /* physically copy the struct job */
1363         memcpy(thejob, pi, sizeof(struct pipe));
1364         thejob->next = NULL;
1365         thejob->running_progs = thejob->num_progs;
1366         thejob->stopped_progs = 0;
1367         thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1368
1369         /*if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) */
1370         {
1371                 char *bar=thejob->text;
1372                 char **foo=pi->progs[0].argv;
1373                 while(foo && *foo) {
1374                         bar += sprintf(bar, "%s ", *foo++);
1375                 }
1376         }
1377
1378         /* we don't wait for background thejobs to return -- append it
1379            to the list of backgrounded thejobs and leave it alone */
1380         printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1381         last_bg_pid = thejob->progs[0].pid;
1382         last_jobid = thejob->jobid;
1383 }
1384
1385 /* remove a backgrounded job */
1386 static void remove_bg_job(struct pipe *pi)
1387 {
1388         struct pipe *prev_pipe;
1389
1390         if (pi == job_list) {
1391                 job_list = pi->next;
1392         } else {
1393                 prev_pipe = job_list;
1394                 while (prev_pipe->next != pi)
1395                         prev_pipe = prev_pipe->next;
1396                 prev_pipe->next = pi->next;
1397         }
1398         if (job_list)
1399                 last_jobid = job_list->jobid;
1400         else
1401                 last_jobid = 0;
1402
1403         pi->stopped_progs = 0;
1404         free_pipe(pi, 0);
1405         free(pi);
1406 }
1407
1408 /* Checks to see if any processes have exited -- if they
1409    have, figure out why and see if a job has completed */
1410 static int checkjobs(struct pipe* fg_pipe)
1411 {
1412         int attributes;
1413         int status;
1414         int prognum = 0;
1415         struct pipe *pi;
1416         pid_t childpid;
1417
1418         attributes = WUNTRACED;
1419         if (fg_pipe==NULL) {
1420                 attributes |= WNOHANG;
1421         }
1422
1423         while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1424                 if (fg_pipe) {
1425                         int i, rcode = 0;
1426                         for (i=0; i < fg_pipe->num_progs; i++) {
1427                                 if (fg_pipe->progs[i].pid == childpid) {
1428                                         if (i==fg_pipe->num_progs-1)
1429                                                 rcode=WEXITSTATUS(status);
1430                                         (fg_pipe->num_progs)--;
1431                                         return(rcode);
1432                                 }
1433                         }
1434                 }
1435
1436                 for (pi = job_list; pi; pi = pi->next) {
1437                         prognum = 0;
1438                         while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1439                                 prognum++;
1440                         }
1441                         if (prognum < pi->num_progs)
1442                                 break;
1443                 }
1444
1445                 if(pi==NULL) {
1446                         debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
1447                         continue;
1448                 }
1449
1450                 if (WIFEXITED(status) || WIFSIGNALED(status)) {
1451                         /* child exited */
1452                         pi->running_progs--;
1453                         pi->progs[prognum].pid = 0;
1454
1455                         if (!pi->running_progs) {
1456                                 printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
1457                                 remove_bg_job(pi);
1458                         }
1459                 } else {
1460                         /* child stopped */
1461                         pi->stopped_progs++;
1462                         pi->progs[prognum].is_stopped = 1;
1463
1464 #if 0
1465                         /* Printing this stuff is a pain, since it tends to
1466                          * overwrite the prompt an inconveinient moments.  So
1467                          * don't do that.  */
1468                         if (pi->stopped_progs == pi->num_progs) {
1469                                 printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
1470                         }
1471 #endif
1472                 }
1473         }
1474
1475         if (childpid == -1 && errno != ECHILD)
1476                 perror_msg("waitpid");
1477
1478         /* move the shell to the foreground */
1479         /*if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) */
1480         /*      perror_msg("tcsetpgrp-2"); */
1481         return -1;
1482 }
1483
1484 /* Figure out our controlling tty, checking in order stderr,
1485  * stdin, and stdout.  If check_pgrp is set, also check that
1486  * we belong to the foreground process group associated with
1487  * that tty.  The value of shell_terminal is needed in order to call
1488  * tcsetpgrp(shell_terminal, ...); */
1489 void controlling_tty(int check_pgrp)
1490 {
1491         pid_t curpgrp;
1492
1493         if ((curpgrp = tcgetpgrp(shell_terminal = 2)) < 0
1494                         && (curpgrp = tcgetpgrp(shell_terminal = 0)) < 0
1495                         && (curpgrp = tcgetpgrp(shell_terminal = 1)) < 0)
1496                 goto shell_terminal_error;
1497
1498         if (check_pgrp && curpgrp != getpgid(0))
1499                 goto shell_terminal_error;
1500
1501         return;
1502
1503 shell_terminal_error:
1504                 shell_terminal = -1;
1505                 return;
1506 }
1507 #endif
1508
1509 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1510  * to finish.  See checkjobs().
1511  *
1512  * return code is normally -1, when the caller has to wait for children
1513  * to finish to determine the exit status of the pipe.  If the pipe
1514  * is a simple builtin command, however, the action is done by the
1515  * time run_pipe_real returns, and the exit code is provided as the
1516  * return value.
1517  *
1518  * The input of the pipe is always stdin, the output is always
1519  * stdout.  The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1520  * because it tries to avoid running the command substitution in
1521  * subshell, when that is in fact necessary.  The subshell process
1522  * now has its stdout directed to the input of the appropriate pipe,
1523  * so this routine is noticeably simpler.
1524  */
1525 static int run_pipe_real(struct pipe *pi)
1526 {
1527         int i;
1528 #ifndef __U_BOOT__
1529         int nextin, nextout;
1530         int pipefds[2];                         /* pipefds[0] is for reading */
1531         struct child_prog *child;
1532         struct built_in_command *x;
1533         char *p;
1534 # if __GNUC__
1535         /* Avoid longjmp clobbering */
1536         (void) &i;
1537         (void) &nextin;
1538         (void) &nextout;
1539         (void) &child;
1540 # endif
1541 #else
1542         int nextin;
1543         int flag = do_repeat ? CMD_FLAG_REPEAT : 0;
1544         struct child_prog *child;
1545         char *p;
1546 # if __GNUC__
1547         /* Avoid longjmp clobbering */
1548         (void) &i;
1549         (void) &nextin;
1550         (void) &child;
1551 # endif
1552 #endif  /* __U_BOOT__ */
1553
1554         nextin = 0;
1555 #ifndef __U_BOOT__
1556         pi->pgrp = -1;
1557 #endif
1558
1559         /* Check if this is a simple builtin (not part of a pipe).
1560          * Builtins within pipes have to fork anyway, and are handled in
1561          * pseudo_exec.  "echo foo | read bar" doesn't work on bash, either.
1562          */
1563         if (pi->num_progs == 1) child = & (pi->progs[0]);
1564 #ifndef __U_BOOT__
1565         if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1566                 int squirrel[] = {-1, -1, -1};
1567                 int rcode;
1568                 debug_printf("non-subshell grouping\n");
1569                 setup_redirects(child, squirrel);
1570                 /* XXX could we merge code with following builtin case,
1571                  * by creating a pseudo builtin that calls run_list_real? */
1572                 rcode = run_list_real(child->group);
1573                 restore_redirects(squirrel);
1574 #else
1575                 if (pi->num_progs == 1 && child->group) {
1576                 int rcode;
1577                 debug_printf("non-subshell grouping\n");
1578                 rcode = run_list_real(child->group);
1579 #endif
1580                 return rcode;
1581         } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1582                 for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
1583                 if (i!=0 && child->argv[i]==NULL) {
1584                         /* assignments, but no command: set the local environment */
1585                         for (i=0; child->argv[i]!=NULL; i++) {
1586
1587                                 /* Ok, this case is tricky.  We have to decide if this is a
1588                                  * local variable, or an already exported variable.  If it is
1589                                  * already exported, we have to export the new value.  If it is
1590                                  * not exported, we need only set this as a local variable.
1591                                  * This junk is all to decide whether or not to export this
1592                                  * variable. */
1593                                 int export_me=0;
1594                                 char *name, *value;
1595                                 name = xstrdup(child->argv[i]);
1596                                 debug_printf("Local environment set: %s\n", name);
1597                                 value = strchr(name, '=');
1598                                 if (value)
1599                                         *value=0;
1600 #ifndef __U_BOOT__
1601                                 if ( get_local_var(name)) {
1602                                         export_me=1;
1603                                 }
1604 #endif
1605                                 free(name);
1606                                 p = insert_var_value(child->argv[i]);
1607                                 set_local_var(p, export_me);
1608                                 if (p != child->argv[i]) free(p);
1609                         }
1610                         return EXIT_SUCCESS;   /* don't worry about errors in set_local_var() yet */
1611                 }
1612                 for (i = 0; is_assignment(child->argv[i]); i++) {
1613                         p = insert_var_value(child->argv[i]);
1614 #ifndef __U_BOOT__
1615                         putenv(strdup(p));
1616 #else
1617                         set_local_var(p, 0);
1618 #endif
1619                         if (p != child->argv[i]) {
1620                                 child->sp--;
1621                                 free(p);
1622                         }
1623                 }
1624                 if (child->sp) {
1625                         char * str = NULL;
1626
1627                         str = make_string(child->argv + i,
1628                                           child->argv_nonnull + i);
1629                         parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1630                         free(str);
1631                         return last_return_code;
1632                 }
1633 #ifndef __U_BOOT__
1634                 for (x = bltins; x->cmd; x++) {
1635                         if (strcmp(child->argv[i], x->cmd) == 0 ) {
1636                                 int squirrel[] = {-1, -1, -1};
1637                                 int rcode;
1638                                 if (x->function == builtin_exec && child->argv[i+1]==NULL) {
1639                                         debug_printf("magic exec\n");
1640                                         setup_redirects(child,NULL);
1641                                         return EXIT_SUCCESS;
1642                                 }
1643                                 debug_printf("builtin inline %s\n", child->argv[0]);
1644                                 /* XXX setup_redirects acts on file descriptors, not FILEs.
1645                                  * This is perfect for work that comes after exec().
1646                                  * Is it really safe for inline use?  Experimentally,
1647                                  * things seem to work with glibc. */
1648                                 setup_redirects(child, squirrel);
1649
1650                                 child->argv += i;  /* XXX horrible hack */
1651                                 rcode = x->function(child);
1652                                 /* XXX restore hack so free() can work right */
1653                                 child->argv -= i;
1654                                 restore_redirects(squirrel);
1655                         }
1656                         return rcode;
1657                 }
1658 #else
1659                 /* check ";", because ,example , argv consist from
1660                  * "help;flinfo" must not execute
1661                  */
1662                 if (strchr(child->argv[i], ';')) {
1663                         printf("Unknown command '%s' - try 'help' or use "
1664                                         "'run' command\n", child->argv[i]);
1665                         return -1;
1666                 }
1667                 /* Process the command */
1668                 return cmd_process(flag, child->argc, child->argv,
1669                                    &flag_repeat, NULL);
1670 #endif
1671         }
1672 #ifndef __U_BOOT__
1673
1674         for (i = 0; i < pi->num_progs; i++) {
1675                 child = & (pi->progs[i]);
1676
1677                 /* pipes are inserted between pairs of commands */
1678                 if ((i + 1) < pi->num_progs) {
1679                         if (pipe(pipefds)<0) perror_msg_and_die("pipe");
1680                         nextout = pipefds[1];
1681                 } else {
1682                         nextout=1;
1683                         pipefds[0] = -1;
1684                 }
1685
1686                 /* XXX test for failed fork()? */
1687                 if (!(child->pid = fork())) {
1688                         /* Set the handling for job control signals back to the default.  */
1689                         signal(SIGINT, SIG_DFL);
1690                         signal(SIGQUIT, SIG_DFL);
1691                         signal(SIGTERM, SIG_DFL);
1692                         signal(SIGTSTP, SIG_DFL);
1693                         signal(SIGTTIN, SIG_DFL);
1694                         signal(SIGTTOU, SIG_DFL);
1695                         signal(SIGCHLD, SIG_DFL);
1696
1697                         close_all();
1698
1699                         if (nextin != 0) {
1700                                 dup2(nextin, 0);
1701                                 close(nextin);
1702                         }
1703                         if (nextout != 1) {
1704                                 dup2(nextout, 1);
1705                                 close(nextout);
1706                         }
1707                         if (pipefds[0]!=-1) {
1708                                 close(pipefds[0]);  /* opposite end of our output pipe */
1709                         }
1710
1711                         /* Like bash, explicit redirects override pipes,
1712                          * and the pipe fd is available for dup'ing. */
1713                         setup_redirects(child,NULL);
1714
1715                         if (interactive && pi->followup!=PIPE_BG) {
1716                                 /* If we (the child) win the race, put ourselves in the process
1717                                  * group whose leader is the first process in this pipe. */
1718                                 if (pi->pgrp < 0) {
1719                                         pi->pgrp = getpid();
1720                                 }
1721                                 if (setpgid(0, pi->pgrp) == 0) {
1722                                         tcsetpgrp(2, pi->pgrp);
1723                                 }
1724                         }
1725
1726                         pseudo_exec(child);
1727                 }
1728
1729
1730                 /* put our child in the process group whose leader is the
1731                    first process in this pipe */
1732                 if (pi->pgrp < 0) {
1733                         pi->pgrp = child->pid;
1734                 }
1735                 /* Don't check for errors.  The child may be dead already,
1736                  * in which case setpgid returns error code EACCES. */
1737                 setpgid(child->pid, pi->pgrp);
1738
1739                 if (nextin != 0)
1740                         close(nextin);
1741                 if (nextout != 1)
1742                         close(nextout);
1743
1744                 /* If there isn't another process, nextin is garbage
1745                    but it doesn't matter */
1746                 nextin = pipefds[0];
1747         }
1748 #endif
1749         return -1;
1750 }
1751
1752 static int run_list_real(struct pipe *pi)
1753 {
1754         char *save_name = NULL;
1755         char **list = NULL;
1756         char **save_list = NULL;
1757         struct pipe *rpipe;
1758         int flag_rep = 0;
1759 #ifndef __U_BOOT__
1760         int save_num_progs;
1761 #endif
1762         int rcode=0, flag_skip=1;
1763         int flag_restore = 0;
1764         int if_code=0, next_if_code=0;  /* need double-buffer to handle elif */
1765         reserved_style rmode, skip_more_in_this_rmode=RES_XXXX;
1766         /* check syntax for "for" */
1767         for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1768                 if ((rpipe->r_mode == RES_IN ||
1769                     rpipe->r_mode == RES_FOR) &&
1770                     (rpipe->next == NULL)) {
1771                                 syntax();
1772 #ifdef __U_BOOT__
1773                                 flag_repeat = 0;
1774 #endif
1775                                 return 1;
1776                 }
1777                 if ((rpipe->r_mode == RES_IN &&
1778                         (rpipe->next->r_mode == RES_IN &&
1779                         rpipe->next->progs->argv != NULL))||
1780                         (rpipe->r_mode == RES_FOR &&
1781                         rpipe->next->r_mode != RES_IN)) {
1782                                 syntax();
1783 #ifdef __U_BOOT__
1784                                 flag_repeat = 0;
1785 #endif
1786                                 return 1;
1787                 }
1788         }
1789         for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1790                 if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
1791                         pi->r_mode == RES_FOR) {
1792 #ifdef __U_BOOT__
1793                                 /* check Ctrl-C */
1794                                 ctrlc();
1795                                 if ((had_ctrlc())) {
1796                                         return 1;
1797                                 }
1798 #endif
1799                                 flag_restore = 0;
1800                                 if (!rpipe) {
1801                                         flag_rep = 0;
1802                                         rpipe = pi;
1803                                 }
1804                 }
1805                 rmode = pi->r_mode;
1806                 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);
1807                 if (rmode == skip_more_in_this_rmode && flag_skip) {
1808                         if (pi->followup == PIPE_SEQ) flag_skip=0;
1809                         continue;
1810                 }
1811                 flag_skip = 1;
1812                 skip_more_in_this_rmode = RES_XXXX;
1813                 if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
1814                 if (rmode == RES_THEN &&  if_code) continue;
1815                 if (rmode == RES_ELSE && !if_code) continue;
1816                 if (rmode == RES_ELIF && !if_code) break;
1817                 if (rmode == RES_FOR && pi->num_progs) {
1818                         if (!list) {
1819                                 /* if no variable values after "in" we skip "for" */
1820                                 if (!pi->next->progs->argv) continue;
1821                                 /* create list of variable values */
1822                                 list = make_list_in(pi->next->progs->argv,
1823                                         pi->progs->argv[0]);
1824                                 save_list = list;
1825                                 save_name = pi->progs->argv[0];
1826                                 pi->progs->argv[0] = NULL;
1827                                 flag_rep = 1;
1828                         }
1829                         if (!(*list)) {
1830                                 free(pi->progs->argv[0]);
1831                                 free(save_list);
1832                                 list = NULL;
1833                                 flag_rep = 0;
1834                                 pi->progs->argv[0] = save_name;
1835 #ifndef __U_BOOT__
1836                                 pi->progs->glob_result.gl_pathv[0] =
1837                                         pi->progs->argv[0];
1838 #endif
1839                                 continue;
1840                         } else {
1841                                 /* insert new value from list for variable */
1842                                 if (pi->progs->argv[0])
1843                                         free(pi->progs->argv[0]);
1844                                 pi->progs->argv[0] = *list++;
1845 #ifndef __U_BOOT__
1846                                 pi->progs->glob_result.gl_pathv[0] =
1847                                         pi->progs->argv[0];
1848 #endif
1849                         }
1850                 }
1851                 if (rmode == RES_IN) continue;
1852                 if (rmode == RES_DO) {
1853                         if (!flag_rep) continue;
1854                 }
1855                 if (rmode == RES_DONE) {
1856                         if (flag_rep) {
1857                                 flag_restore = 1;
1858                         } else {
1859                                 rpipe = NULL;
1860                         }
1861                 }
1862                 if (pi->num_progs == 0) continue;
1863 #ifndef __U_BOOT__
1864                 save_num_progs = pi->num_progs; /* save number of programs */
1865 #endif
1866                 rcode = run_pipe_real(pi);
1867                 debug_printf("run_pipe_real returned %d\n",rcode);
1868 #ifndef __U_BOOT__
1869                 if (rcode!=-1) {
1870                         /* We only ran a builtin: rcode was set by the return value
1871                          * of run_pipe_real(), and we don't need to wait for anything. */
1872                 } else if (pi->followup==PIPE_BG) {
1873                         /* XXX check bash's behavior with nontrivial pipes */
1874                         /* XXX compute jobid */
1875                         /* XXX what does bash do with attempts to background builtins? */
1876                         insert_bg_job(pi);
1877                         rcode = EXIT_SUCCESS;
1878                 } else {
1879                         if (interactive) {
1880                                 /* move the new process group into the foreground */
1881                                 if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1882                                         perror_msg("tcsetpgrp-3");
1883                                 rcode = checkjobs(pi);
1884                                 /* move the shell to the foreground */
1885                                 if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1886                                         perror_msg("tcsetpgrp-4");
1887                         } else {
1888                                 rcode = checkjobs(pi);
1889                         }
1890                         debug_printf("checkjobs returned %d\n",rcode);
1891                 }
1892                 last_return_code=rcode;
1893 #else
1894                 if (rcode < -1) {
1895                         last_return_code = -rcode - 2;
1896                         return -2;      /* exit */
1897                 }
1898                 last_return_code=(rcode == 0) ? 0 : 1;
1899 #endif
1900 #ifndef __U_BOOT__
1901                 pi->num_progs = save_num_progs; /* restore number of programs */
1902 #endif
1903                 if ( rmode == RES_IF || rmode == RES_ELIF )
1904                         next_if_code=rcode;  /* can be overwritten a number of times */
1905                 if (rmode == RES_WHILE)
1906                         flag_rep = !last_return_code;
1907                 if (rmode == RES_UNTIL)
1908                         flag_rep = last_return_code;
1909                 if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
1910                      (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
1911                         skip_more_in_this_rmode=rmode;
1912 #ifndef __U_BOOT__
1913                 checkjobs(NULL);
1914 #endif
1915         }
1916         return rcode;
1917 }
1918
1919 /* broken, of course, but OK for testing */
1920 static char *indenter(int i)
1921 {
1922         static char blanks[]="                                    ";
1923         return &blanks[sizeof(blanks)-i-1];
1924 }
1925
1926 /* return code is the exit status of the pipe */
1927 static int free_pipe(struct pipe *pi, int indent)
1928 {
1929         char **p;
1930         struct child_prog *child;
1931 #ifndef __U_BOOT__
1932         struct redir_struct *r, *rnext;
1933 #endif
1934         int a, i, ret_code=0;
1935         char *ind = indenter(indent);
1936
1937 #ifndef __U_BOOT__
1938         if (pi->stopped_progs > 0)
1939                 return ret_code;
1940         final_printf("%s run pipe: (pid %d)\n",ind,getpid());
1941 #endif
1942         for (i=0; i<pi->num_progs; i++) {
1943                 child = &pi->progs[i];
1944                 final_printf("%s  command %d:\n",ind,i);
1945                 if (child->argv) {
1946                         for (a=0,p=child->argv; *p; a++,p++) {
1947                                 final_printf("%s   argv[%d] = %s\n",ind,a,*p);
1948                         }
1949 #ifndef __U_BOOT__
1950                         globfree(&child->glob_result);
1951 #else
1952                         for (a = 0; a < child->argc; a++) {
1953                                 free(child->argv[a]);
1954                         }
1955                         free(child->argv);
1956                         free(child->argv_nonnull);
1957                         child->argc = 0;
1958 #endif
1959                         child->argv=NULL;
1960                 } else if (child->group) {
1961 #ifndef __U_BOOT__
1962                         final_printf("%s   begin group (subshell:%d)\n",ind, child->subshell);
1963 #endif
1964                         ret_code = free_pipe_list(child->group,indent+3);
1965                         final_printf("%s   end group\n",ind);
1966                 } else {
1967                         final_printf("%s   (nil)\n",ind);
1968                 }
1969 #ifndef __U_BOOT__
1970                 for (r=child->redirects; r; r=rnext) {
1971                         final_printf("%s   redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
1972                         if (r->dup == -1) {
1973                                 /* guard against the case >$FOO, where foo is unset or blank */
1974                                 if (r->word.gl_pathv) {
1975                                         final_printf(" %s\n", *r->word.gl_pathv);
1976                                         globfree(&r->word);
1977                                 }
1978                         } else {
1979                                 final_printf("&%d\n", r->dup);
1980                         }
1981                         rnext=r->next;
1982                         free(r);
1983                 }
1984                 child->redirects=NULL;
1985 #endif
1986         }
1987         free(pi->progs);   /* children are an array, they get freed all at once */
1988         pi->progs=NULL;
1989         return ret_code;
1990 }
1991
1992 static int free_pipe_list(struct pipe *head, int indent)
1993 {
1994         int rcode=0;   /* if list has no members */
1995         struct pipe *pi, *next;
1996         char *ind = indenter(indent);
1997         for (pi=head; pi; pi=next) {
1998                 final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
1999                 rcode = free_pipe(pi, indent);
2000                 final_printf("%s pipe followup code %d\n", ind, pi->followup);
2001                 next=pi->next;
2002                 pi->next=NULL;
2003                 free(pi);
2004         }
2005         return rcode;
2006 }
2007
2008 /* Select which version we will use */
2009 static int run_list(struct pipe *pi)
2010 {
2011         int rcode=0;
2012 #ifndef __U_BOOT__
2013         if (fake_mode==0) {
2014 #endif
2015                 rcode = run_list_real(pi);
2016 #ifndef __U_BOOT__
2017         }
2018 #endif
2019         /* free_pipe_list has the side effect of clearing memory
2020          * In the long run that function can be merged with run_list_real,
2021          * but doing that now would hobble the debugging effort. */
2022         free_pipe_list(pi,0);
2023         return rcode;
2024 }
2025
2026 /* The API for glob is arguably broken.  This routine pushes a non-matching
2027  * string into the output structure, removing non-backslashed backslashes.
2028  * If someone can prove me wrong, by performing this function within the
2029  * original glob(3) api, feel free to rewrite this routine into oblivion.
2030  * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
2031  * XXX broken if the last character is '\\', check that before calling.
2032  */
2033 #ifndef __U_BOOT__
2034 static int globhack(const char *src, int flags, glob_t *pglob)
2035 {
2036         int cnt=0, pathc;
2037         const char *s;
2038         char *dest;
2039         for (cnt=1, s=src; s && *s; s++) {
2040                 if (*s == '\\') s++;
2041                 cnt++;
2042         }
2043         dest = malloc(cnt);
2044         if (!dest) return GLOB_NOSPACE;
2045         if (!(flags & GLOB_APPEND)) {
2046                 pglob->gl_pathv=NULL;
2047                 pglob->gl_pathc=0;
2048                 pglob->gl_offs=0;
2049                 pglob->gl_offs=0;
2050         }
2051         pathc = ++pglob->gl_pathc;
2052         pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
2053         if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
2054         pglob->gl_pathv[pathc-1]=dest;
2055         pglob->gl_pathv[pathc]=NULL;
2056         for (s=src; s && *s; s++, dest++) {
2057                 if (*s == '\\') s++;
2058                 *dest = *s;
2059         }
2060         *dest='\0';
2061         return 0;
2062 }
2063
2064 /* XXX broken if the last character is '\\', check that before calling */
2065 static int glob_needed(const char *s)
2066 {
2067         for (; *s; s++) {
2068                 if (*s == '\\') s++;
2069                 if (strchr("*[?",*s)) return 1;
2070         }
2071         return 0;
2072 }
2073
2074 #if 0
2075 static void globprint(glob_t *pglob)
2076 {
2077         int i;
2078         debug_printf("glob_t at %p:\n", pglob);
2079         debug_printf("  gl_pathc=%d  gl_pathv=%p  gl_offs=%d  gl_flags=%d\n",
2080                 pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
2081         for (i=0; i<pglob->gl_pathc; i++)
2082                 debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
2083                         pglob->gl_pathv[i], pglob->gl_pathv[i]);
2084 }
2085 #endif
2086
2087 static int xglob(o_string *dest, int flags, glob_t *pglob)
2088 {
2089         int gr;
2090
2091         /* short-circuit for null word */
2092         /* we can code this better when the debug_printf's are gone */
2093         if (dest->length == 0) {
2094                 if (dest->nonnull) {
2095                         /* bash man page calls this an "explicit" null */
2096                         gr = globhack(dest->data, flags, pglob);
2097                         debug_printf("globhack returned %d\n",gr);
2098                 } else {
2099                         return 0;
2100                 }
2101         } else if (glob_needed(dest->data)) {
2102                 gr = glob(dest->data, flags, NULL, pglob);
2103                 debug_printf("glob returned %d\n",gr);
2104                 if (gr == GLOB_NOMATCH) {
2105                         /* quote removal, or more accurately, backslash removal */
2106                         gr = globhack(dest->data, flags, pglob);
2107                         debug_printf("globhack returned %d\n",gr);
2108                 }
2109         } else {
2110                 gr = globhack(dest->data, flags, pglob);
2111                 debug_printf("globhack returned %d\n",gr);
2112         }
2113         if (gr == GLOB_NOSPACE)
2114                 error_msg_and_die("out of memory during glob");
2115         if (gr != 0) { /* GLOB_ABORTED ? */
2116                 error_msg("glob(3) error %d",gr);
2117         }
2118         /* globprint(glob_target); */
2119         return gr;
2120 }
2121 #endif
2122
2123 #ifdef __U_BOOT__
2124 static char *get_dollar_var(char ch);
2125 #endif
2126
2127 /* This is used to get/check local shell variables */
2128 char *get_local_var(const char *s)
2129 {
2130         struct variables *cur;
2131
2132         if (!s)
2133                 return NULL;
2134
2135 #ifdef __U_BOOT__
2136         if (*s == '$')
2137                 return get_dollar_var(s[1]);
2138 #endif
2139
2140         for (cur = top_vars; cur; cur=cur->next)
2141                 if(strcmp(cur->name, s)==0)
2142                         return cur->value;
2143         return NULL;
2144 }
2145
2146 /* This is used to set local shell variables
2147    flg_export==0 if only local (not exporting) variable
2148    flg_export==1 if "new" exporting environ
2149    flg_export>1  if current startup environ (not call putenv()) */
2150 int set_local_var(const char *s, int flg_export)
2151 {
2152         char *name, *value;
2153         int result=0;
2154         struct variables *cur;
2155
2156 #ifdef __U_BOOT__
2157         /* might be possible! */
2158         if (!isalpha(*s))
2159                 return -1;
2160 #endif
2161
2162         name=strdup(s);
2163
2164 #ifdef __U_BOOT__
2165         if (getenv(name) != NULL) {
2166                 printf ("ERROR: "
2167                                 "There is a global environment variable with the same name.\n");
2168                 free(name);
2169                 return -1;
2170         }
2171 #endif
2172         /* Assume when we enter this function that we are already in
2173          * NAME=VALUE format.  So the first order of business is to
2174          * split 's' on the '=' into 'name' and 'value' */
2175         value = strchr(name, '=');
2176         if (value == NULL || *(value + 1) == 0) {
2177                 free(name);
2178                 return -1;
2179         }
2180         *value++ = 0;
2181
2182         for(cur = top_vars; cur; cur = cur->next) {
2183                 if(strcmp(cur->name, name)==0)
2184                         break;
2185         }
2186
2187         if(cur) {
2188                 if(strcmp(cur->value, value)==0) {
2189                         if(flg_export>0 && cur->flg_export==0)
2190                                 cur->flg_export=flg_export;
2191                         else
2192                                 result++;
2193                 } else {
2194                         if(cur->flg_read_only) {
2195                                 error_msg("%s: readonly variable", name);
2196                                 result = -1;
2197                         } else {
2198                                 if(flg_export>0 || cur->flg_export>1)
2199                                         cur->flg_export=1;
2200                                 free(cur->value);
2201
2202                                 cur->value = strdup(value);
2203                         }
2204                 }
2205         } else {
2206                 cur = malloc(sizeof(struct variables));
2207                 if(!cur) {
2208                         result = -1;
2209                 } else {
2210                         cur->name = strdup(name);
2211                         if (cur->name == NULL) {
2212                                 free(cur);
2213                                 result = -1;
2214                         } else {
2215                                 struct variables *bottom = top_vars;
2216                                 cur->value = strdup(value);
2217                                 cur->next = NULL;
2218                                 cur->flg_export = flg_export;
2219                                 cur->flg_read_only = 0;
2220                                 while(bottom->next) bottom=bottom->next;
2221                                 bottom->next = cur;
2222                         }
2223                 }
2224         }
2225
2226 #ifndef __U_BOOT__
2227         if(result==0 && cur->flg_export==1) {
2228                 *(value-1) = '=';
2229                 result = putenv(name);
2230         } else {
2231 #endif
2232                 free(name);
2233 #ifndef __U_BOOT__
2234                 if(result>0)            /* equivalent to previous set */
2235                         result = 0;
2236         }
2237 #endif
2238         return result;
2239 }
2240
2241 void unset_local_var(const char *name)
2242 {
2243         struct variables *cur;
2244
2245         if (name) {
2246                 for (cur = top_vars; cur; cur=cur->next) {
2247                         if(strcmp(cur->name, name)==0)
2248                                 break;
2249                 }
2250                 if (cur != NULL) {
2251                         struct variables *next = top_vars;
2252                         if(cur->flg_read_only) {
2253                                 error_msg("%s: readonly variable", name);
2254                                 return;
2255                         } else {
2256 #ifndef __U_BOOT__
2257                                 if(cur->flg_export)
2258                                         unsetenv(cur->name);
2259 #endif
2260                                 free(cur->name);
2261                                 free(cur->value);
2262                                 while (next->next != cur)
2263                                         next = next->next;
2264                                 next->next = cur->next;
2265                         }
2266                         free(cur);
2267                 }
2268         }
2269 }
2270
2271 static int is_assignment(const char *s)
2272 {
2273         if (s == NULL)
2274                 return 0;
2275
2276         if (!isalpha(*s)) return 0;
2277         ++s;
2278         while(isalnum(*s) || *s=='_') ++s;
2279         return *s=='=';
2280 }
2281
2282 #ifndef __U_BOOT__
2283 /* the src parameter allows us to peek forward to a possible &n syntax
2284  * for file descriptor duplication, e.g., "2>&1".
2285  * Return code is 0 normally, 1 if a syntax error is detected in src.
2286  * Resource errors (in xmalloc) cause the process to exit */
2287 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
2288         struct in_str *input)
2289 {
2290         struct child_prog *child=ctx->child;
2291         struct redir_struct *redir = child->redirects;
2292         struct redir_struct *last_redir=NULL;
2293
2294         /* Create a new redir_struct and drop it onto the end of the linked list */
2295         while(redir) {
2296                 last_redir=redir;
2297                 redir=redir->next;
2298         }
2299         redir = xmalloc(sizeof(struct redir_struct));
2300         redir->next=NULL;
2301         redir->word.gl_pathv=NULL;
2302         if (last_redir) {
2303                 last_redir->next=redir;
2304         } else {
2305                 child->redirects=redir;
2306         }
2307
2308         redir->type=style;
2309         redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
2310
2311         debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
2312
2313         /* Check for a '2>&1' type redirect */
2314         redir->dup = redirect_dup_num(input);
2315         if (redir->dup == -2) return 1;  /* syntax error */
2316         if (redir->dup != -1) {
2317                 /* Erik had a check here that the file descriptor in question
2318                  * is legit; I postpone that to "run time"
2319                  * A "-" representation of "close me" shows up as a -3 here */
2320                 debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
2321         } else {
2322                 /* We do _not_ try to open the file that src points to,
2323                  * since we need to return and let src be expanded first.
2324                  * Set ctx->pending_redirect, so we know what to do at the
2325                  * end of the next parsed word.
2326                  */
2327                 ctx->pending_redirect = redir;
2328         }
2329         return 0;
2330 }
2331 #endif
2332
2333 static struct pipe *new_pipe(void)
2334 {
2335         struct pipe *pi;
2336         pi = xmalloc(sizeof(struct pipe));
2337         pi->num_progs = 0;
2338         pi->progs = NULL;
2339         pi->next = NULL;
2340         pi->followup = 0;  /* invalid */
2341         pi->r_mode = RES_NONE;
2342         return pi;
2343 }
2344
2345 static void initialize_context(struct p_context *ctx)
2346 {
2347         ctx->pipe=NULL;
2348 #ifndef __U_BOOT__
2349         ctx->pending_redirect=NULL;
2350 #endif
2351         ctx->child=NULL;
2352         ctx->list_head=new_pipe();
2353         ctx->pipe=ctx->list_head;
2354         ctx->w=RES_NONE;
2355         ctx->stack=NULL;
2356 #ifdef __U_BOOT__
2357         ctx->old_flag=0;
2358 #endif
2359         done_command(ctx);   /* creates the memory for working child */
2360 }
2361
2362 /* normal return is 0
2363  * if a reserved word is found, and processed, return 1
2364  * should handle if, then, elif, else, fi, for, while, until, do, done.
2365  * case, function, and select are obnoxious, save those for later.
2366  */
2367 struct reserved_combo {
2368         char *literal;
2369         int code;
2370         long flag;
2371 };
2372 /* Mostly a list of accepted follow-up reserved words.
2373  * FLAG_END means we are done with the sequence, and are ready
2374  * to turn the compound list into a command.
2375  * FLAG_START means the word must start a new compound list.
2376  */
2377 static struct reserved_combo reserved_list[] = {
2378         { "if",    RES_IF,    FLAG_THEN | FLAG_START },
2379         { "then",  RES_THEN,  FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2380         { "elif",  RES_ELIF,  FLAG_THEN },
2381         { "else",  RES_ELSE,  FLAG_FI   },
2382         { "fi",    RES_FI,    FLAG_END  },
2383         { "for",   RES_FOR,   FLAG_IN   | FLAG_START },
2384         { "while", RES_WHILE, FLAG_DO   | FLAG_START },
2385         { "until", RES_UNTIL, FLAG_DO   | FLAG_START },
2386         { "in",    RES_IN,    FLAG_DO   },
2387         { "do",    RES_DO,    FLAG_DONE },
2388         { "done",  RES_DONE,  FLAG_END  }
2389 };
2390 #define NRES (sizeof(reserved_list)/sizeof(struct reserved_combo))
2391
2392 static int reserved_word(o_string *dest, struct p_context *ctx)
2393 {
2394         struct reserved_combo *r;
2395         for (r=reserved_list;
2396                 r<reserved_list+NRES; r++) {
2397                 if (strcmp(dest->data, r->literal) == 0) {
2398                         debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2399                         if (r->flag & FLAG_START) {
2400                                 struct p_context *new = xmalloc(sizeof(struct p_context));
2401                                 debug_printf("push stack\n");
2402                                 if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2403                                         syntax();
2404                                         free(new);
2405                                         ctx->w = RES_SNTX;
2406                                         b_reset(dest);
2407                                         return 1;
2408                                 }
2409                                 *new = *ctx;   /* physical copy */
2410                                 initialize_context(ctx);
2411                                 ctx->stack=new;
2412                         } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2413                                 syntax();
2414                                 ctx->w = RES_SNTX;
2415                                 b_reset(dest);
2416                                 return 1;
2417                         }
2418                         ctx->w=r->code;
2419                         ctx->old_flag = r->flag;
2420                         if (ctx->old_flag & FLAG_END) {
2421                                 struct p_context *old;
2422                                 debug_printf("pop stack\n");
2423                                 done_pipe(ctx,PIPE_SEQ);
2424                                 old = ctx->stack;
2425                                 old->child->group = ctx->list_head;
2426 #ifndef __U_BOOT__
2427                                 old->child->subshell = 0;
2428 #endif
2429                                 *ctx = *old;   /* physical copy */
2430                                 free(old);
2431                         }
2432                         b_reset (dest);
2433                         return 1;
2434                 }
2435         }
2436         return 0;
2437 }
2438
2439 /* normal return is 0.
2440  * Syntax or xglob errors return 1. */
2441 static int done_word(o_string *dest, struct p_context *ctx)
2442 {
2443         struct child_prog *child=ctx->child;
2444 #ifndef __U_BOOT__
2445         glob_t *glob_target;
2446         int gr, flags = 0;
2447 #else
2448         char *str, *s;
2449         int argc, cnt;
2450 #endif
2451
2452         debug_printf("done_word: %s %p\n", dest->data, child);
2453         if (dest->length == 0 && !dest->nonnull) {
2454                 debug_printf("  true null, ignored\n");
2455                 return 0;
2456         }
2457 #ifndef __U_BOOT__
2458         if (ctx->pending_redirect) {
2459                 glob_target = &ctx->pending_redirect->word;
2460         } else {
2461 #endif
2462                 if (child->group) {
2463                         syntax();
2464                         return 1;  /* syntax error, groups and arglists don't mix */
2465                 }
2466                 if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2467                         debug_printf("checking %s for reserved-ness\n",dest->data);
2468                         if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2469                 }
2470 #ifndef __U_BOOT__
2471                 glob_target = &child->glob_result;
2472                 if (child->argv) flags |= GLOB_APPEND;
2473 #else
2474                 for (cnt = 1, s = dest->data; s && *s; s++) {
2475                         if (*s == '\\') s++;
2476                         cnt++;
2477                 }
2478                 str = malloc(cnt);
2479                 if (!str) return 1;
2480                 if ( child->argv == NULL) {
2481                         child->argc=0;
2482                 }
2483                 argc = ++child->argc;
2484                 child->argv = realloc(child->argv, (argc+1)*sizeof(*child->argv));
2485                 if (child->argv == NULL) {
2486                         free(str);
2487                         return 1;
2488                 }
2489                 child->argv_nonnull = realloc(child->argv_nonnull,
2490                                         (argc+1)*sizeof(*child->argv_nonnull));
2491                 if (child->argv_nonnull == NULL) {
2492                         free(str);
2493                         return 1;
2494                 }
2495                 child->argv[argc-1]=str;
2496                 child->argv_nonnull[argc-1] = dest->nonnull;
2497                 child->argv[argc]=NULL;
2498                 child->argv_nonnull[argc] = 0;
2499                 for (s = dest->data; s && *s; s++,str++) {
2500                         if (*s == '\\') s++;
2501                         *str = *s;
2502                 }
2503                 *str = '\0';
2504 #endif
2505 #ifndef __U_BOOT__
2506         }
2507         gr = xglob(dest, flags, glob_target);
2508         if (gr != 0) return 1;
2509 #endif
2510
2511         b_reset(dest);
2512 #ifndef __U_BOOT__
2513         if (ctx->pending_redirect) {
2514                 ctx->pending_redirect=NULL;
2515                 if (glob_target->gl_pathc != 1) {
2516                         error_msg("ambiguous redirect");
2517                         return 1;
2518                 }
2519         } else {
2520                 child->argv = glob_target->gl_pathv;
2521         }
2522 #endif
2523         if (ctx->w == RES_FOR) {
2524                 done_word(dest,ctx);
2525                 done_pipe(ctx,PIPE_SEQ);
2526         }
2527         return 0;
2528 }
2529
2530 /* The only possible error here is out of memory, in which case
2531  * xmalloc exits. */
2532 static int done_command(struct p_context *ctx)
2533 {
2534         /* The child is really already in the pipe structure, so
2535          * advance the pipe counter and make a new, null child.
2536          * Only real trickiness here is that the uncommitted
2537          * child structure, to which ctx->child points, is not
2538          * counted in pi->num_progs. */
2539         struct pipe *pi=ctx->pipe;
2540         struct child_prog *prog=ctx->child;
2541
2542         if (prog && prog->group == NULL
2543                  && prog->argv == NULL
2544 #ifndef __U_BOOT__
2545                  && prog->redirects == NULL) {
2546 #else
2547                                                                                 ) {
2548 #endif
2549                 debug_printf("done_command: skipping null command\n");
2550                 return 0;
2551         } else if (prog) {
2552                 pi->num_progs++;
2553                 debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2554         } else {
2555                 debug_printf("done_command: initializing\n");
2556         }
2557         pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2558
2559         prog = pi->progs + pi->num_progs;
2560 #ifndef __U_BOOT__
2561         prog->redirects = NULL;
2562 #endif
2563         prog->argv = NULL;
2564         prog->argv_nonnull = NULL;
2565 #ifndef __U_BOOT__
2566         prog->is_stopped = 0;
2567 #endif
2568         prog->group = NULL;
2569 #ifndef __U_BOOT__
2570         prog->glob_result.gl_pathv = NULL;
2571         prog->family = pi;
2572 #endif
2573         prog->sp = 0;
2574         ctx->child = prog;
2575         prog->type = ctx->type;
2576
2577         /* but ctx->pipe and ctx->list_head remain unchanged */
2578         return 0;
2579 }
2580
2581 static int done_pipe(struct p_context *ctx, pipe_style type)
2582 {
2583         struct pipe *new_p;
2584         done_command(ctx);  /* implicit closure of previous command */
2585         debug_printf("done_pipe, type %d\n", type);
2586         ctx->pipe->followup = type;
2587         ctx->pipe->r_mode = ctx->w;
2588         new_p=new_pipe();
2589         ctx->pipe->next = new_p;
2590         ctx->pipe = new_p;
2591         ctx->child = NULL;
2592         done_command(ctx);  /* set up new pipe to accept commands */
2593         return 0;
2594 }
2595
2596 #ifndef __U_BOOT__
2597 /* peek ahead in the in_str to find out if we have a "&n" construct,
2598  * as in "2>&1", that represents duplicating a file descriptor.
2599  * returns either -2 (syntax error), -1 (no &), or the number found.
2600  */
2601 static int redirect_dup_num(struct in_str *input)
2602 {
2603         int ch, d=0, ok=0;
2604         ch = b_peek(input);
2605         if (ch != '&') return -1;
2606
2607         b_getch(input);  /* get the & */
2608         ch=b_peek(input);
2609         if (ch == '-') {
2610                 b_getch(input);
2611                 return -3;  /* "-" represents "close me" */
2612         }
2613         while (isdigit(ch)) {
2614                 d = d*10+(ch-'0');
2615                 ok=1;
2616                 b_getch(input);
2617                 ch = b_peek(input);
2618         }
2619         if (ok) return d;
2620
2621         error_msg("ambiguous redirect");
2622         return -2;
2623 }
2624
2625 /* If a redirect is immediately preceded by a number, that number is
2626  * supposed to tell which file descriptor to redirect.  This routine
2627  * looks for such preceding numbers.  In an ideal world this routine
2628  * needs to handle all the following classes of redirects...
2629  *     echo 2>foo     # redirects fd  2 to file "foo", nothing passed to echo
2630  *     echo 49>foo    # redirects fd 49 to file "foo", nothing passed to echo
2631  *     echo -2>foo    # redirects fd  1 to file "foo",    "-2" passed to echo
2632  *     echo 49x>foo   # redirects fd  1 to file "foo",   "49x" passed to echo
2633  * A -1 output from this program means no valid number was found, so the
2634  * caller should use the appropriate default for this redirection.
2635  */
2636 static int redirect_opt_num(o_string *o)
2637 {
2638         int num;
2639
2640         if (o->length==0) return -1;
2641         for(num=0; num<o->length; num++) {
2642                 if (!isdigit(*(o->data+num))) {
2643                         return -1;
2644                 }
2645         }
2646         /* reuse num (and save an int) */
2647         num=atoi(o->data);
2648         b_reset(o);
2649         return num;
2650 }
2651
2652 FILE *generate_stream_from_list(struct pipe *head)
2653 {
2654         FILE *pf;
2655 #if 1
2656         int pid, channel[2];
2657         if (pipe(channel)<0) perror_msg_and_die("pipe");
2658         pid=fork();
2659         if (pid<0) {
2660                 perror_msg_and_die("fork");
2661         } else if (pid==0) {
2662                 close(channel[0]);
2663                 if (channel[1] != 1) {
2664                         dup2(channel[1],1);
2665                         close(channel[1]);
2666                 }
2667 #if 0
2668 #define SURROGATE "surrogate response"
2669                 write(1,SURROGATE,sizeof(SURROGATE));
2670                 _exit(run_list(head));
2671 #else
2672                 _exit(run_list_real(head));   /* leaks memory */
2673 #endif
2674         }
2675         debug_printf("forked child %d\n",pid);
2676         close(channel[1]);
2677         pf = fdopen(channel[0],"r");
2678         debug_printf("pipe on FILE *%p\n",pf);
2679 #else
2680         free_pipe_list(head,0);
2681         pf=popen("echo surrogate response","r");
2682         debug_printf("started fake pipe on FILE *%p\n",pf);
2683 #endif
2684         return pf;
2685 }
2686
2687 /* this version hacked for testing purposes */
2688 /* return code is exit status of the process that is run. */
2689 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2690 {
2691         int retcode;
2692         o_string result=NULL_O_STRING;
2693         struct p_context inner;
2694         FILE *p;
2695         struct in_str pipe_str;
2696         initialize_context(&inner);
2697
2698         /* recursion to generate command */
2699         retcode = parse_stream(&result, &inner, input, subst_end);
2700         if (retcode != 0) return retcode;  /* syntax error or EOF */
2701         done_word(&result, &inner);
2702         done_pipe(&inner, PIPE_SEQ);
2703         b_free(&result);
2704
2705         p=generate_stream_from_list(inner.list_head);
2706         if (p==NULL) return 1;
2707         mark_open(fileno(p));
2708         setup_file_in_str(&pipe_str, p);
2709
2710         /* now send results of command back into original context */
2711         retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2712         /* XXX In case of a syntax error, should we try to kill the child?
2713          * That would be tough to do right, so just read until EOF. */
2714         if (retcode == 1) {
2715                 while (b_getch(&pipe_str)!=EOF) { /* discard */ };
2716         }
2717
2718         debug_printf("done reading from pipe, pclose()ing\n");
2719         /* This is the step that wait()s for the child.  Should be pretty
2720          * safe, since we just read an EOF from its stdout.  We could try
2721          * to better, by using wait(), and keeping track of background jobs
2722          * at the same time.  That would be a lot of work, and contrary
2723          * to the KISS philosophy of this program. */
2724         mark_closed(fileno(p));
2725         retcode=pclose(p);
2726         free_pipe_list(inner.list_head,0);
2727         debug_printf("pclosed, retcode=%d\n",retcode);
2728         /* XXX this process fails to trim a single trailing newline */
2729         return retcode;
2730 }
2731
2732 static int parse_group(o_string *dest, struct p_context *ctx,
2733         struct in_str *input, int ch)
2734 {
2735         int rcode, endch=0;
2736         struct p_context sub;
2737         struct child_prog *child = ctx->child;
2738         if (child->argv) {
2739                 syntax();
2740                 return 1;  /* syntax error, groups and arglists don't mix */
2741         }
2742         initialize_context(&sub);
2743         switch(ch) {
2744                 case '(': endch=')'; child->subshell=1; break;
2745                 case '{': endch='}'; break;
2746                 default: syntax();   /* really logic error */
2747         }
2748         rcode=parse_stream(dest,&sub,input,endch);
2749         done_word(dest,&sub); /* finish off the final word in the subcontext */
2750         done_pipe(&sub, PIPE_SEQ);  /* and the final command there, too */
2751         child->group = sub.list_head;
2752         return rcode;
2753         /* child remains "open", available for possible redirects */
2754 }
2755 #endif
2756
2757 /* basically useful version until someone wants to get fancier,
2758  * see the bash man page under "Parameter Expansion" */
2759 static char *lookup_param(char *src)
2760 {
2761         char *p;
2762         char *sep;
2763         char *default_val = NULL;
2764         int assign = 0;
2765         int expand_empty = 0;
2766
2767         if (!src)
2768                 return NULL;
2769
2770         sep = strchr(src, ':');
2771
2772         if (sep) {
2773                 *sep = '\0';
2774                 if (*(sep + 1) == '-')
2775                         default_val = sep+2;
2776                 if (*(sep + 1) == '=') {
2777                         default_val = sep+2;
2778                         assign = 1;
2779                 }
2780                 if (*(sep + 1) == '+') {
2781                         default_val = sep+2;
2782                         expand_empty = 1;
2783                 }
2784         }
2785
2786         p = getenv(src);
2787         if (!p)
2788                 p = get_local_var(src);
2789
2790         if (!p || strlen(p) == 0) {
2791                 p = default_val;
2792                 if (assign) {
2793                         char *var = malloc(strlen(src)+strlen(default_val)+2);
2794                         if (var) {
2795                                 sprintf(var, "%s=%s", src, default_val);
2796                                 set_local_var(var, 0);
2797                         }
2798                         free(var);
2799                 }
2800         } else if (expand_empty) {
2801                 p += strlen(p);
2802         }
2803
2804         if (sep)
2805                 *sep = ':';
2806
2807         return p;
2808 }
2809
2810 #ifdef __U_BOOT__
2811 static char *get_dollar_var(char ch)
2812 {
2813         static char buf[40];
2814
2815         buf[0] = '\0';
2816         switch (ch) {
2817                 case '?':
2818                         sprintf(buf, "%u", (unsigned int)last_return_code);
2819                         break;
2820                 default:
2821                         return NULL;
2822         }
2823         return buf;
2824 }
2825 #endif
2826
2827 /* return code: 0 for OK, 1 for syntax error */
2828 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2829 {
2830 #ifndef __U_BOOT__
2831         int i, advance=0;
2832 #else
2833         int advance=0;
2834 #endif
2835 #ifndef __U_BOOT__
2836         char sep[]=" ";
2837 #endif
2838         int ch = input->peek(input);  /* first character after the $ */
2839         debug_printf("handle_dollar: ch=%c\n",ch);
2840         if (isalpha(ch)) {
2841                 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2842                 ctx->child->sp++;
2843                 while(ch=b_peek(input),isalnum(ch) || ch=='_') {
2844                         b_getch(input);
2845                         b_addchr(dest,ch);
2846                 }
2847                 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2848 #ifndef __U_BOOT__
2849         } else if (isdigit(ch)) {
2850                 i = ch-'0';  /* XXX is $0 special? */
2851                 if (i<global_argc) {
2852                         parse_string(dest, ctx, global_argv[i]); /* recursion */
2853                 }
2854                 advance = 1;
2855 #endif
2856         } else switch (ch) {
2857 #ifndef __U_BOOT__
2858                 case '$':
2859                         b_adduint(dest,getpid());
2860                         advance = 1;
2861                         break;
2862                 case '!':
2863                         if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2864                         advance = 1;
2865                         break;
2866 #endif
2867                 case '?':
2868 #ifndef __U_BOOT__
2869                         b_adduint(dest,last_return_code);
2870 #else
2871                         ctx->child->sp++;
2872                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2873                         b_addchr(dest, '$');
2874                         b_addchr(dest, '?');
2875                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2876 #endif
2877                         advance = 1;
2878                         break;
2879 #ifndef __U_BOOT__
2880                 case '#':
2881                         b_adduint(dest,global_argc ? global_argc-1 : 0);
2882                         advance = 1;
2883                         break;
2884 #endif
2885                 case '{':
2886                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2887                         ctx->child->sp++;
2888                         b_getch(input);
2889                         /* XXX maybe someone will try to escape the '}' */
2890                         while(ch=b_getch(input),ch!=EOF && ch!='}') {
2891                                 b_addchr(dest,ch);
2892                         }
2893                         if (ch != '}') {
2894                                 syntax();
2895                                 return 1;
2896                         }
2897                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2898                         break;
2899 #ifndef __U_BOOT__
2900                 case '(':
2901                         b_getch(input);
2902                         process_command_subs(dest, ctx, input, ')');
2903                         break;
2904                 case '*':
2905                         sep[0]=ifs[0];
2906                         for (i=1; i<global_argc; i++) {
2907                                 parse_string(dest, ctx, global_argv[i]);
2908                                 if (i+1 < global_argc) parse_string(dest, ctx, sep);
2909                         }
2910                         break;
2911                 case '@':
2912                 case '-':
2913                 case '_':
2914                         /* still unhandled, but should be eventually */
2915                         error_msg("unhandled syntax: $%c",ch);
2916                         return 1;
2917                         break;
2918 #endif
2919                 default:
2920                         b_addqchr(dest,'$',dest->quote);
2921         }
2922         /* Eat the character if the flag was set.  If the compiler
2923          * is smart enough, we could substitute "b_getch(input);"
2924          * for all the "advance = 1;" above, and also end up with
2925          * a nice size-optimized program.  Hah!  That'll be the day.
2926          */
2927         if (advance) b_getch(input);
2928         return 0;
2929 }
2930
2931 #ifndef __U_BOOT__
2932 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2933 {
2934         struct in_str foo;
2935         setup_string_in_str(&foo, src);
2936         return parse_stream(dest, ctx, &foo, '\0');
2937 }
2938 #endif
2939
2940 /* return code is 0 for normal exit, 1 for syntax error */
2941 static int parse_stream(o_string *dest, struct p_context *ctx,
2942                         struct in_str *input, int end_trigger)
2943 {
2944         unsigned int ch, m;
2945 #ifndef __U_BOOT__
2946         int redir_fd;
2947         redir_type redir_style;
2948 #endif
2949         int next;
2950
2951         /* Only double-quote state is handled in the state variable dest->quote.
2952          * A single-quote triggers a bypass of the main loop until its mate is
2953          * found.  When recursing, quote state is passed in via dest->quote. */
2954
2955         debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2956         while ((ch=b_getch(input))!=EOF) {
2957                 m = map[ch];
2958 #ifdef __U_BOOT__
2959                 if (input->__promptme == 0) return 1;
2960 #endif
2961                 next = (ch == '\n') ? 0 : b_peek(input);
2962
2963                 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d - %c\n",
2964                         ch >= ' ' ? ch : '.', ch, m,
2965                         dest->quote, ctx->stack == NULL ? '*' : '.');
2966
2967                 if (m==0 || ((m==1 || m==2) && dest->quote)) {
2968                         b_addqchr(dest, ch, dest->quote);
2969                 } else {
2970                         if (m==2) {  /* unquoted IFS */
2971                                 if (done_word(dest, ctx)) {
2972                                         return 1;
2973                                 }
2974                                 /* If we aren't performing a substitution, treat a newline as a
2975                                  * command separator.  */
2976                                 if (end_trigger != '\0' && ch=='\n')
2977                                         done_pipe(ctx,PIPE_SEQ);
2978                         }
2979                         if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2980                                 debug_printf("leaving parse_stream (triggered)\n");
2981                                 return 0;
2982                         }
2983 #if 0
2984                         if (ch=='\n') {
2985                                 /* Yahoo!  Time to run with it! */
2986                                 done_pipe(ctx,PIPE_SEQ);
2987                                 run_list(ctx->list_head);
2988                                 initialize_context(ctx);
2989                         }
2990 #endif
2991                         if (m!=2) switch (ch) {
2992                 case '#':
2993                         if (dest->length == 0 && !dest->quote) {
2994                                 while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
2995                         } else {
2996                                 b_addqchr(dest, ch, dest->quote);
2997                         }
2998                         break;
2999                 case '\\':
3000                         if (next == EOF) {
3001                                 syntax();
3002                                 return 1;
3003                         }
3004                         b_addqchr(dest, '\\', dest->quote);
3005                         b_addqchr(dest, b_getch(input), dest->quote);
3006                         break;
3007                 case '$':
3008                         if (handle_dollar(dest, ctx, input)!=0) return 1;
3009                         break;
3010                 case '\'':
3011                         dest->nonnull = 1;
3012                         while(ch=b_getch(input),ch!=EOF && ch!='\'') {
3013 #ifdef __U_BOOT__
3014                                 if(input->__promptme == 0) return 1;
3015 #endif
3016                                 b_addchr(dest,ch);
3017                         }
3018                         if (ch==EOF) {
3019                                 syntax();
3020                                 return 1;
3021                         }
3022                         break;
3023                 case '"':
3024                         dest->nonnull = 1;
3025                         dest->quote = !dest->quote;
3026                         break;
3027 #ifndef __U_BOOT__
3028                 case '`':
3029                         process_command_subs(dest, ctx, input, '`');
3030                         break;
3031                 case '>':
3032                         redir_fd = redirect_opt_num(dest);
3033                         done_word(dest, ctx);
3034                         redir_style=REDIRECT_OVERWRITE;
3035                         if (next == '>') {
3036                                 redir_style=REDIRECT_APPEND;
3037                                 b_getch(input);
3038                         } else if (next == '(') {
3039                                 syntax();   /* until we support >(list) Process Substitution */
3040                                 return 1;
3041                         }
3042                         setup_redirect(ctx, redir_fd, redir_style, input);
3043                         break;
3044                 case '<':
3045                         redir_fd = redirect_opt_num(dest);
3046                         done_word(dest, ctx);
3047                         redir_style=REDIRECT_INPUT;
3048                         if (next == '<') {
3049                                 redir_style=REDIRECT_HEREIS;
3050                                 b_getch(input);
3051                         } else if (next == '>') {
3052                                 redir_style=REDIRECT_IO;
3053                                 b_getch(input);
3054                         } else if (next == '(') {
3055                                 syntax();   /* until we support <(list) Process Substitution */
3056                                 return 1;
3057                         }
3058                         setup_redirect(ctx, redir_fd, redir_style, input);
3059                         break;
3060 #endif
3061                 case ';':
3062                         done_word(dest, ctx);
3063                         done_pipe(ctx,PIPE_SEQ);
3064                         break;
3065                 case '&':
3066                         done_word(dest, ctx);
3067                         if (next=='&') {
3068                                 b_getch(input);
3069                                 done_pipe(ctx,PIPE_AND);
3070                         } else {
3071 #ifndef __U_BOOT__
3072                                 done_pipe(ctx,PIPE_BG);
3073 #else
3074                                 syntax_err();
3075                                 return 1;
3076 #endif
3077                         }
3078                         break;
3079                 case '|':
3080                         done_word(dest, ctx);
3081                         if (next=='|') {
3082                                 b_getch(input);
3083                                 done_pipe(ctx,PIPE_OR);
3084                         } else {
3085                                 /* we could pick up a file descriptor choice here
3086                                  * with redirect_opt_num(), but bash doesn't do it.
3087                                  * "echo foo 2| cat" yields "foo 2". */
3088 #ifndef __U_BOOT__
3089                                 done_command(ctx);
3090 #else
3091                                 syntax_err();
3092                                 return 1;
3093 #endif
3094                         }
3095                         break;
3096 #ifndef __U_BOOT__
3097                 case '(':
3098                 case '{':
3099                         if (parse_group(dest, ctx, input, ch)!=0) return 1;
3100                         break;
3101                 case ')':
3102                 case '}':
3103                         syntax();   /* Proper use of this character caught by end_trigger */
3104                         return 1;
3105                         break;
3106 #endif
3107                 case SUBSTED_VAR_SYMBOL:
3108                         dest->nonnull = 1;
3109                         while (ch = b_getch(input), ch != EOF &&
3110                             ch != SUBSTED_VAR_SYMBOL) {
3111                                 debug_printf("subst, pass=%d\n", ch);
3112                                 if (input->__promptme == 0)
3113                                         return 1;
3114                                 b_addchr(dest, ch);
3115                         }
3116                         debug_printf("subst, term=%d\n", ch);
3117                         if (ch == EOF) {
3118                                 syntax();
3119                                 return 1;
3120                         }
3121                         break;
3122                 default:
3123                         syntax();   /* this is really an internal logic error */
3124                         return 1;
3125                         }
3126                 }
3127         }
3128         /* complain if quote?  No, maybe we just finished a command substitution
3129          * that was quoted.  Example:
3130          * $ echo "`cat foo` plus more"
3131          * and we just got the EOF generated by the subshell that ran "cat foo"
3132          * The only real complaint is if we got an EOF when end_trigger != '\0',
3133          * that is, we were really supposed to get end_trigger, and never got
3134          * one before the EOF.  Can't use the standard "syntax error" return code,
3135          * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
3136         debug_printf("leaving parse_stream (EOF)\n");
3137         if (end_trigger != '\0') return -1;
3138         return 0;
3139 }
3140
3141 static void mapset(const unsigned char *set, int code)
3142 {
3143         const unsigned char *s;
3144         for (s=set; *s; s++) map[*s] = code;
3145 }
3146
3147 static void update_ifs_map(void)
3148 {
3149         /* char *ifs and char map[256] are both globals. */
3150         ifs = (uchar *)getenv("IFS");
3151         if (ifs == NULL) ifs=(uchar *)" \t\n";
3152         /* Precompute a list of 'flow through' behavior so it can be treated
3153          * quickly up front.  Computation is necessary because of IFS.
3154          * Special case handling of IFS == " \t\n" is not implemented.
3155          * The map[] array only really needs two bits each, and on most machines
3156          * that would be faster because of the reduced L1 cache footprint.
3157          */
3158         memset(map,0,sizeof(map)); /* most characters flow through always */
3159 #ifndef __U_BOOT__
3160         mapset((uchar *)"\\$'\"`", 3);      /* never flow through */
3161         mapset((uchar *)"<>;&|(){}#", 1);   /* flow through if quoted */
3162 #else
3163         {
3164                 uchar subst[2] = {SUBSTED_VAR_SYMBOL, 0};
3165                 mapset(subst, 3);       /* never flow through */
3166         }
3167         mapset((uchar *)"\\$'\"", 3);       /* never flow through */
3168         mapset((uchar *)";&|#", 1);         /* flow through if quoted */
3169 #endif
3170         mapset(ifs, 2);            /* also flow through if quoted */
3171 }
3172
3173 /* most recursion does not come through here, the exeception is
3174  * from builtin_source() */
3175 static int parse_stream_outer(struct in_str *inp, int flag)
3176 {
3177
3178         struct p_context ctx;
3179         o_string temp=NULL_O_STRING;
3180         int rcode;
3181 #ifdef __U_BOOT__
3182         int code = 1;
3183 #endif
3184         do {
3185                 ctx.type = flag;
3186                 initialize_context(&ctx);
3187                 update_ifs_map();
3188                 if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset((uchar *)";$&|", 0);
3189                 inp->promptmode=1;
3190                 rcode = parse_stream(&temp, &ctx, inp,
3191                                      flag & FLAG_CONT_ON_NEWLINE ? -1 : '\n');
3192 #ifdef __U_BOOT__
3193                 if (rcode == 1) flag_repeat = 0;
3194 #endif
3195                 if (rcode != 1 && ctx.old_flag != 0) {
3196                         syntax();
3197 #ifdef __U_BOOT__
3198                         flag_repeat = 0;
3199 #endif
3200                 }
3201                 if (rcode != 1 && ctx.old_flag == 0) {
3202                         done_word(&temp, &ctx);
3203                         done_pipe(&ctx,PIPE_SEQ);
3204 #ifndef __U_BOOT__
3205                         run_list(ctx.list_head);
3206 #else
3207                         code = run_list(ctx.list_head);
3208                         if (code == -2) {       /* exit */
3209                                 b_free(&temp);
3210                                 code = 0;
3211                                 /* XXX hackish way to not allow exit from main loop */
3212                                 if (inp->peek == file_peek) {
3213                                         printf("exit not allowed from main input shell.\n");
3214                                         continue;
3215                                 }
3216                                 break;
3217                         }
3218                         if (code == -1)
3219                             flag_repeat = 0;
3220 #endif
3221                 } else {
3222                         if (ctx.old_flag != 0) {
3223                                 free(ctx.stack);
3224                                 b_reset(&temp);
3225                         }
3226 #ifdef __U_BOOT__
3227                         if (inp->__promptme == 0) printf("<INTERRUPT>\n");
3228                         inp->__promptme = 1;
3229 #endif
3230                         temp.nonnull = 0;
3231                         temp.quote = 0;
3232                         inp->p = NULL;
3233                         free_pipe_list(ctx.list_head,0);
3234                 }
3235                 b_free(&temp);
3236         /* loop on syntax errors, return on EOF */
3237         } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP) &&
3238                 (inp->peek != static_peek || b_peek(inp)));
3239 #ifndef __U_BOOT__
3240         return 0;
3241 #else
3242         return (code != 0) ? 1 : 0;
3243 #endif /* __U_BOOT__ */
3244 }
3245
3246 #ifndef __U_BOOT__
3247 static int parse_string_outer(const char *s, int flag)
3248 #else
3249 int parse_string_outer(const char *s, int flag)
3250 #endif  /* __U_BOOT__ */
3251 {
3252         struct in_str input;
3253 #ifdef __U_BOOT__
3254         char *p = NULL;
3255         int rcode;
3256         if (!s)
3257                 return 1;
3258         if (!*s)
3259                 return 0;
3260         if (!(p = strchr(s, '\n')) || *++p) {
3261                 p = xmalloc(strlen(s) + 2);
3262                 strcpy(p, s);
3263                 strcat(p, "\n");
3264                 setup_string_in_str(&input, p);
3265                 rcode = parse_stream_outer(&input, flag);
3266                 free(p);
3267                 return rcode;
3268         } else {
3269 #endif
3270         setup_string_in_str(&input, s);
3271         return parse_stream_outer(&input, flag);
3272 #ifdef __U_BOOT__
3273         }
3274 #endif
3275 }
3276
3277 #ifndef __U_BOOT__
3278 static int parse_file_outer(FILE *f)
3279 #else
3280 int parse_file_outer(void)
3281 #endif
3282 {
3283         int rcode;
3284         struct in_str input;
3285 #ifndef __U_BOOT__
3286         setup_file_in_str(&input, f);
3287 #else
3288         setup_file_in_str(&input);
3289 #endif
3290         rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
3291         return rcode;
3292 }
3293
3294 #ifdef __U_BOOT__
3295 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3296 static void u_boot_hush_reloc(void)
3297 {
3298         unsigned long addr;
3299         struct reserved_combo *r;
3300
3301         for (r=reserved_list; r<reserved_list+NRES; r++) {
3302                 addr = (ulong) (r->literal) + gd->reloc_off;
3303                 r->literal = (char *)addr;
3304         }
3305 }
3306 #endif
3307
3308 int u_boot_hush_start(void)
3309 {
3310         if (top_vars == NULL) {
3311                 top_vars = malloc(sizeof(struct variables));
3312                 top_vars->name = "HUSH_VERSION";
3313                 top_vars->value = "0.01";
3314                 top_vars->next = NULL;
3315                 top_vars->flg_export = 0;
3316                 top_vars->flg_read_only = 1;
3317 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3318                 u_boot_hush_reloc();
3319 #endif
3320         }
3321         return 0;
3322 }
3323
3324 static void *xmalloc(size_t size)
3325 {
3326         void *p = NULL;
3327
3328         if (!(p = malloc(size))) {
3329             printf("ERROR : memory not allocated\n");
3330             for(;;);
3331         }
3332         return p;
3333 }
3334
3335 static void *xrealloc(void *ptr, size_t size)
3336 {
3337         void *p = NULL;
3338
3339         if (!(p = realloc(ptr, size))) {
3340             printf("ERROR : memory not allocated\n");
3341             for(;;);
3342         }
3343         return p;
3344 }
3345 #endif /* __U_BOOT__ */
3346
3347 #ifndef __U_BOOT__
3348 /* Make sure we have a controlling tty.  If we get started under a job
3349  * aware app (like bash for example), make sure we are now in charge so
3350  * we don't fight over who gets the foreground */
3351 static void setup_job_control(void)
3352 {
3353         static pid_t shell_pgrp;
3354         /* Loop until we are in the foreground.  */
3355         while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
3356                 kill (- shell_pgrp, SIGTTIN);
3357
3358         /* Ignore interactive and job-control signals.  */
3359         signal(SIGINT, SIG_IGN);
3360         signal(SIGQUIT, SIG_IGN);
3361         signal(SIGTERM, SIG_IGN);
3362         signal(SIGTSTP, SIG_IGN);
3363         signal(SIGTTIN, SIG_IGN);
3364         signal(SIGTTOU, SIG_IGN);
3365         signal(SIGCHLD, SIG_IGN);
3366
3367         /* Put ourselves in our own process group.  */
3368         setsid();
3369         shell_pgrp = getpid ();
3370         setpgid (shell_pgrp, shell_pgrp);
3371
3372         /* Grab control of the terminal.  */
3373         tcsetpgrp(shell_terminal, shell_pgrp);
3374 }
3375
3376 int hush_main(int argc, char * const *argv)
3377 {
3378         int opt;
3379         FILE *input;
3380         char **e = environ;
3381
3382         /* XXX what should these be while sourcing /etc/profile? */
3383         global_argc = argc;
3384         global_argv = argv;
3385
3386         /* (re?) initialize globals.  Sometimes hush_main() ends up calling
3387          * hush_main(), therefore we cannot rely on the BSS to zero out this
3388          * stuff.  Reset these to 0 every time. */
3389         ifs = NULL;
3390         /* map[] is taken care of with call to update_ifs_map() */
3391         fake_mode = 0;
3392         interactive = 0;
3393         close_me_head = NULL;
3394         last_bg_pid = 0;
3395         job_list = NULL;
3396         last_jobid = 0;
3397
3398         /* Initialize some more globals to non-zero values */
3399         set_cwd();
3400 #ifdef CONFIG_FEATURE_COMMAND_EDITING
3401         cmdedit_set_initial_prompt();
3402 #else
3403         PS1 = NULL;
3404 #endif
3405         PS2 = "> ";
3406
3407         /* initialize our shell local variables with the values
3408          * currently living in the environment */
3409         if (e) {
3410                 for (; *e; e++)
3411                         set_local_var(*e, 2);   /* without call putenv() */
3412         }
3413
3414         last_return_code=EXIT_SUCCESS;
3415
3416
3417         if (argv[0] && argv[0][0] == '-') {
3418                 debug_printf("\nsourcing /etc/profile\n");
3419                 if ((input = fopen("/etc/profile", "r")) != NULL) {
3420                         mark_open(fileno(input));
3421                         parse_file_outer(input);
3422                         mark_closed(fileno(input));
3423                         fclose(input);
3424                 }
3425         }
3426         input=stdin;
3427
3428         while ((opt = getopt(argc, argv, "c:xif")) > 0) {
3429                 switch (opt) {
3430                         case 'c':
3431                                 {
3432                                         global_argv = argv+optind;
3433                                         global_argc = argc-optind;
3434                                         opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
3435                                         goto final_return;
3436                                 }
3437                                 break;
3438                         case 'i':
3439                                 interactive++;
3440                                 break;
3441                         case 'f':
3442                                 fake_mode++;
3443                                 break;
3444                         default:
3445 #ifndef BB_VER
3446                                 fprintf(stderr, "Usage: sh [FILE]...\n"
3447                                                 "   or: sh -c command [args]...\n\n");
3448                                 exit(EXIT_FAILURE);
3449 #else
3450                                 show_usage();
3451 #endif
3452                 }
3453         }
3454         /* A shell is interactive if the `-i' flag was given, or if all of
3455          * the following conditions are met:
3456          *        no -c command
3457          *    no arguments remaining or the -s flag given
3458          *    standard input is a terminal
3459          *    standard output is a terminal
3460          *    Refer to Posix.2, the description of the `sh' utility. */
3461         if (argv[optind]==NULL && input==stdin &&
3462                         isatty(fileno(stdin)) && isatty(fileno(stdout))) {
3463                 interactive++;
3464         }
3465
3466         debug_printf("\ninteractive=%d\n", interactive);
3467         if (interactive) {
3468                 /* Looks like they want an interactive shell */
3469 #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
3470                 printf( "\n\n" BB_BANNER " hush - the humble shell v0.01 (testing)\n");
3471                 printf( "Enter 'help' for a list of built-in commands.\n\n");
3472 #endif
3473                 setup_job_control();
3474         }
3475
3476         if (argv[optind]==NULL) {
3477                 opt=parse_file_outer(stdin);
3478                 goto final_return;
3479         }
3480
3481         debug_printf("\nrunning script '%s'\n", argv[optind]);
3482         global_argv = argv+optind;
3483         global_argc = argc-optind;
3484         input = xfopen(argv[optind], "r");
3485         opt = parse_file_outer(input);
3486
3487 #ifdef CONFIG_FEATURE_CLEAN_UP
3488         fclose(input);
3489         if (cwd && cwd != unknown)
3490                 free((char*)cwd);
3491         {
3492                 struct variables *cur, *tmp;
3493                 for(cur = top_vars; cur; cur = tmp) {
3494                         tmp = cur->next;
3495                         if (!cur->flg_read_only) {
3496                                 free(cur->name);
3497                                 free(cur->value);
3498                                 free(cur);
3499                         }
3500                 }
3501         }
3502 #endif
3503
3504 final_return:
3505         return(opt?opt:last_return_code);
3506 }
3507 #endif
3508
3509 static char *insert_var_value(char *inp)
3510 {
3511         return insert_var_value_sub(inp, 0);
3512 }
3513
3514 static char *insert_var_value_sub(char *inp, int tag_subst)
3515 {
3516         int res_str_len = 0;
3517         int len;
3518         int done = 0;
3519         char *p, *p1, *res_str = NULL;
3520
3521         while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
3522                 /* check the beginning of the string for normal characters */
3523                 if (p != inp) {
3524                         /* copy any characters to the result string */
3525                         len = p - inp;
3526                         res_str = xrealloc(res_str, (res_str_len + len));
3527                         strncpy((res_str + res_str_len), inp, len);
3528                         res_str_len += len;
3529                 }
3530                 inp = ++p;
3531                 /* find the ending marker */
3532                 p = strchr(inp, SPECIAL_VAR_SYMBOL);
3533                 *p = '\0';
3534                 /* look up the value to substitute */
3535                 if ((p1 = lookup_param(inp))) {
3536                         if (tag_subst)
3537                                 len = res_str_len + strlen(p1) + 2;
3538                         else
3539                                 len = res_str_len + strlen(p1);
3540                         res_str = xrealloc(res_str, (1 + len));
3541                         if (tag_subst) {
3542                                 /*
3543                                  * copy the variable value to the result
3544                                  * string
3545                                  */
3546                                 strcpy((res_str + res_str_len + 1), p1);
3547
3548                                 /*
3549                                  * mark the replaced text to be accepted as
3550                                  * is
3551                                  */
3552                                 res_str[res_str_len] = SUBSTED_VAR_SYMBOL;
3553                                 res_str[res_str_len + 1 + strlen(p1)] =
3554                                         SUBSTED_VAR_SYMBOL;
3555                         } else
3556                                 /*
3557                                  * copy the variable value to the result
3558                                  * string
3559                                  */
3560                                 strcpy((res_str + res_str_len), p1);
3561
3562                         res_str_len = len;
3563                 }
3564                 *p = SPECIAL_VAR_SYMBOL;
3565                 inp = ++p;
3566                 done = 1;
3567         }
3568         if (done) {
3569                 res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
3570                 strcpy((res_str + res_str_len), inp);
3571                 while ((p = strchr(res_str, '\n'))) {
3572                         *p = ' ';
3573                 }
3574         }
3575         return (res_str == NULL) ? inp : res_str;
3576 }
3577
3578 static char **make_list_in(char **inp, char *name)
3579 {
3580         int len, i;
3581         int name_len = strlen(name);
3582         int n = 0;
3583         char **list;
3584         char *p1, *p2, *p3;
3585
3586         /* create list of variable values */
3587         list = xmalloc(sizeof(*list));
3588         for (i = 0; inp[i]; i++) {
3589                 p3 = insert_var_value(inp[i]);
3590                 p1 = p3;
3591                 while (*p1) {
3592                         if (*p1 == ' ') {
3593                                 p1++;
3594                                 continue;
3595                         }
3596                         if ((p2 = strchr(p1, ' '))) {
3597                                 len = p2 - p1;
3598                         } else {
3599                                 len = strlen(p1);
3600                                 p2 = p1 + len;
3601                         }
3602                         /* we use n + 2 in realloc for list,because we add
3603                          * new element and then we will add NULL element */
3604                         list = xrealloc(list, sizeof(*list) * (n + 2));
3605                         list[n] = xmalloc(2 + name_len + len);
3606                         strcpy(list[n], name);
3607                         strcat(list[n], "=");
3608                         strncat(list[n], p1, len);
3609                         list[n++][name_len + len + 1] = '\0';
3610                         p1 = p2;
3611                 }
3612                 if (p3 != inp[i]) free(p3);
3613         }
3614         list[n] = NULL;
3615         return list;
3616 }
3617
3618 /*
3619  * Make new string for parser
3620  * inp     - array of argument strings to flatten
3621  * nonnull - indicates argument was quoted when originally parsed
3622  */
3623 static char *make_string(char **inp, int *nonnull)
3624 {
3625         char *p;
3626         char *str = NULL;
3627         int n;
3628         int len = 2;
3629         char *noeval_str;
3630         int noeval = 0;
3631
3632         noeval_str = get_local_var("HUSH_NO_EVAL");
3633         if (noeval_str != NULL && *noeval_str != '0' && *noeval_str != '\0')
3634                 noeval = 1;
3635         for (n = 0; inp[n]; n++) {
3636                 p = insert_var_value_sub(inp[n], noeval);
3637                 str = xrealloc(str, (len + strlen(p) + (2 * nonnull[n])));
3638                 if (n) {
3639                         strcat(str, " ");
3640                 } else {
3641                         *str = '\0';
3642                 }
3643                 if (nonnull[n])
3644                         strcat(str, "'");
3645                 strcat(str, p);
3646                 if (nonnull[n])
3647                         strcat(str, "'");
3648                 len = strlen(str) + 3;
3649                 if (p != inp[n]) free(p);
3650         }
3651         len = strlen(str);
3652         *(str + len) = '\n';
3653         *(str + len + 1) = '\0';
3654         return str;
3655 }
3656
3657 #ifdef __U_BOOT__
3658 static int do_showvar(cmd_tbl_t *cmdtp, int flag, int argc,
3659                       char * const argv[])
3660 {
3661         int i, k;
3662         int rcode = 0;
3663         struct variables *cur;
3664
3665         if (argc == 1) {                /* Print all env variables      */
3666                 for (cur = top_vars; cur; cur = cur->next) {
3667                         printf ("%s=%s\n", cur->name, cur->value);
3668                         if (ctrlc ()) {
3669                                 puts ("\n ** Abort\n");
3670                                 return 1;
3671                         }
3672                 }
3673                 return 0;
3674         }
3675         for (i = 1; i < argc; ++i) {    /* print single env variables   */
3676                 char *name = argv[i];
3677
3678                 k = -1;
3679                 for (cur = top_vars; cur; cur = cur->next) {
3680                         if(strcmp (cur->name, name) == 0) {
3681                                 k = 0;
3682                                 printf ("%s=%s\n", cur->name, cur->value);
3683                         }
3684                         if (ctrlc ()) {
3685                                 puts ("\n ** Abort\n");
3686                                 return 1;
3687                         }
3688                 }
3689                 if (k < 0) {
3690                         printf ("## Error: \"%s\" not defined\n", name);
3691                         rcode ++;
3692                 }
3693         }
3694         return rcode;
3695 }
3696
3697 U_BOOT_CMD(
3698         showvar, CONFIG_SYS_MAXARGS, 1, do_showvar,
3699         "print local hushshell variables",
3700         "\n    - print values of all hushshell variables\n"
3701         "showvar name ...\n"
3702         "    - print value of hushshell variable 'name'"
3703 );
3704
3705 #endif
3706 /****************************************************************************/