common/cli_hush.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * sh.c -- a prototype Bourne shell grammar parser
   4  *      Intended to follow the original Thompson and Ritchie
   5  *      "small and simple is beautiful" philosophy, which
   6  *      incidentally is a good match to today's BusyBox.
   7  *
   8  * Copyright (C) 2000,2001  Larry Doolittle  <larry@doolittle.boa.org>
   9  *
  10  * Credits:
  11  *      The parser routines proper are all original material, first
  12  *      written Dec 2000 and Jan 2001 by Larry Doolittle.
  13  *      The execution engine, the builtins, and much of the underlying
  14  *      support has been adapted from busybox-0.49pre's lash,
  15  *      which is Copyright (C) 2000 by Lineo, Inc., and
  16  *      written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>.
  17  *      That, in turn, is based in part on ladsh.c, by Michael K. Johnson and
  18  *      Erik W. Troan, which they placed in the public domain.  I don't know
  19  *      how much of the Johnson/Troan code has survived the repeated rewrites.
  20  * Other credits:
  21  *      b_addchr() derived from similar w_addchar function in glibc-2.2
  22  *      setup_redirect(), redirect_opt_num(), and big chunks of main()
  23  *        and many builtins derived from contributions by Erik Andersen
  24  *      miscellaneous bugfixes from Matt Kraai
  25  *
  26  * There are two big (and related) architecture differences between
  27  * this parser and the lash parser.  One is that this version is
  28  * actually designed from the ground up to understand nearly all
  29  * of the Bourne grammar.  The second, consequential change is that
  30  * the parser and input reader have been turned inside out.  Now,
  31  * the parser is in control, and asks for input as needed.  The old
  32  * way had the input reader in control, and it asked for parsing to
  33  * take place as needed.  The new way makes it much easier to properly
  34  * handle the recursion implicit in the various substitutions, especially
  35  * across continuation lines.
  36  *
  37  * Bash grammar not implemented: (how many of these were in original sh?)
  38  *      $@ (those sure look like weird quoting rules)
  39  *      $_
  40  *      ! negation operator for pipes
  41  *      &> and >& redirection of stdout+stderr
  42  *      Brace Expansion
  43  *      Tilde Expansion
  44  *      fancy forms of Parameter Expansion
  45  *      aliases
  46  *      Arithmetic Expansion
  47  *      <(list) and >(list) Process Substitution
  48  *      reserved words: case, esac, select, function
  49  *      Here Documents ( << word )
  50  *      Functions
  51  * Major bugs:
  52  *      job handling woefully incomplete and buggy
  53  *      reserved word execution woefully incomplete and buggy
  54  * to-do:
  55  *      port selected bugfixes from post-0.49 busybox lash - done?
  56  *      finish implementing reserved words: for, while, until, do, done
  57  *      change { and } from special chars to reserved words
  58  *      builtins: break, continue, eval, return, set, trap, ulimit
  59  *      test magic exec
  60  *      handle children going into background
  61  *      clean up recognition of null pipes
  62  *      check setting of global_argc and global_argv
  63  *      control-C handling, probably with longjmp
  64  *      follow IFS rules more precisely, including update semantics
  65  *      figure out what to do with backslash-newline
  66  *      explain why we use signal instead of sigaction
  67  *      propagate syntax errors, die on resource errors?
  68  *      continuation lines, both explicit and implicit - done?
  69  *      memory leak finding and plugging - done?
  70  *      more testing, especially quoting rules and redirection
  71  *      document how quoting rules not precisely followed for variable assignments
  72  *      maybe change map[] to use 2-bit entries
  73  *      (eventually) remove all the printf's
  74  */
  75
  76 #define __U_BOOT__
  77 #ifdef __U_BOOT__
  78 #include <common.h>         /* readline */
  79 #include <env.h>
  80 #include <malloc.h>         /* malloc, free, realloc*/
  81 #include <linux/ctype.h>    /* isalpha, isdigit */
  82 #include <console.h>
  83 #include <bootretry.h>
  84 #include <cli.h>
  85 #include <cli_hush.h>
  86 #include <command.h>        /* find_cmd */
  87 #include <asm/global_data.h>
  88 #endif
  89 #ifndef __U_BOOT__
  90 #include <ctype.h>     /* isalpha, isdigit */
  91 #include <unistd.h>    /* getpid */
  92 #include <stdlib.h>    /* getenv, atoi */
  93 #include <string.h>    /* strchr */
  94 #include <stdio.h>     /* popen etc. */
  95 #include <glob.h>      /* glob, of course */
  96 #include <stdarg.h>    /* va_list */
  97 #include <errno.h>
  98 #include <fcntl.h>
  99 #include <getopt.h>    /* should be pretty obvious */
 100
 101 #include <sys/stat.h>  /* ulimit */
 102 #include <sys/types.h>
 103 #include <sys/wait.h>
 104 #include <signal.h>
 105
 106 /* #include <dmalloc.h> */
 107
 108 #if 1
 109 #include "busybox.h"
 110 #include "cmdedit.h"
 111 #else
 112 #define applet_name "hush"
 113 #include "standalone.h"
 114 #define hush_main main
 115 #define BB_BANNER
 116 #endif
 117 #endif
 118 #define SPECIAL_VAR_SYMBOL 03
 119 #define SUBSTED_VAR_SYMBOL 04
 120 #ifndef __U_BOOT__
 121 #define FLAG_EXIT_FROM_LOOP 1
 122 #define FLAG_PARSE_SEMICOLON (1 << 1)           /* symbol ';' is special for parser */
 123 #define FLAG_REPARSING       (1 << 2)           /* >= 2nd pass */
 124
 125 #endif
 126
 127 #ifdef __U_BOOT__
 128 DECLARE_GLOBAL_DATA_PTR;
 129
 130 #define EXIT_SUCCESS 0
 131 #define EOF -1
 132 #define syntax() syntax_err()
 133 #define xstrdup strdup
 134 #define error_msg printf
 135 #else
 136 typedef enum {
 137         REDIRECT_INPUT     = 1,
 138         REDIRECT_OVERWRITE = 2,
 139         REDIRECT_APPEND    = 3,
 140         REDIRECT_HEREIS    = 4,
 141         REDIRECT_IO        = 5
 142 } redir_type;
 143
 144 /* The descrip member of this structure is only used to make debugging
 145  * output pretty */
 146 struct {int mode; int default_fd; char *descrip;} redir_table[] = {
 147         { 0,                         0, "()" },
 148         { O_RDONLY,                  0, "<"  },
 149         { O_CREAT|O_TRUNC|O_WRONLY,  1, ">"  },
 150         { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
 151         { O_RDONLY,                 -1, "<<" },
 152         { O_RDWR,                    1, "<>" }
 153 };
 154 #endif
 155
 156 typedef enum {
 157         PIPE_SEQ = 1,
 158         PIPE_AND = 2,
 159         PIPE_OR  = 3,
 160         PIPE_BG  = 4,
 161 } pipe_style;
 162
 163 /* might eventually control execution */
 164 typedef enum {
 165         RES_NONE  = 0,
 166         RES_IF    = 1,
 167         RES_THEN  = 2,
 168         RES_ELIF  = 3,
 169         RES_ELSE  = 4,
 170         RES_FI    = 5,
 171         RES_FOR   = 6,
 172         RES_WHILE = 7,
 173         RES_UNTIL = 8,
 174         RES_DO    = 9,
 175         RES_DONE  = 10,
 176         RES_XXXX  = 11,
 177         RES_IN    = 12,
 178         RES_SNTX  = 13
 179 } reserved_style;
 180 #define FLAG_END   (1<<RES_NONE)
 181 #define FLAG_IF    (1<<RES_IF)
 182 #define FLAG_THEN  (1<<RES_THEN)
 183 #define FLAG_ELIF  (1<<RES_ELIF)
 184 #define FLAG_ELSE  (1<<RES_ELSE)
 185 #define FLAG_FI    (1<<RES_FI)
 186 #define FLAG_FOR   (1<<RES_FOR)
 187 #define FLAG_WHILE (1<<RES_WHILE)
 188 #define FLAG_UNTIL (1<<RES_UNTIL)
 189 #define FLAG_DO    (1<<RES_DO)
 190 #define FLAG_DONE  (1<<RES_DONE)
 191 #define FLAG_IN    (1<<RES_IN)
 192 #define FLAG_START (1<<RES_XXXX)
 193
 194 /* This holds pointers to the various results of parsing */
 195 struct p_context {
 196         struct child_prog *child;
 197         struct pipe *list_head;
 198         struct pipe *pipe;
 199 #ifndef __U_BOOT__
 200         struct redir_struct *pending_redirect;
 201 #endif
 202         reserved_style w;
 203         int old_flag;                           /* for figuring out valid reserved words */
 204         struct p_context *stack;
 205         int type;                       /* define type of parser : ";$" common or special symbol */
 206         /* How about quoting status? */
 207 };
 208
 209 #ifndef __U_BOOT__
 210 struct redir_struct {
 211         redir_type type;                        /* type of redirection */
 212         int fd;                                         /* file descriptor being redirected */
 213         int dup;                                        /* -1, or file descriptor being duplicated */
 214         struct redir_struct *next;      /* pointer to the next redirect in the list */
 215         glob_t word;                            /* *word.gl_pathv is the filename */
 216 };
 217 #endif
 218
 219 struct child_prog {
 220 #ifndef __U_BOOT__
 221         pid_t pid;                                      /* 0 if exited */
 222 #endif
 223         char **argv;                            /* program name and arguments */
 224         /* was quoted when parsed; copy of struct o_string.nonnull field */
 225         int *argv_nonnull;
 226 #ifdef __U_BOOT__
 227         int    argc;                            /* number of program arguments */
 228 #endif
 229         struct pipe *group;                     /* if non-NULL, first in group or subshell */
 230 #ifndef __U_BOOT__
 231         int subshell;                           /* flag, non-zero if group must be forked */
 232         struct redir_struct *redirects; /* I/O redirections */
 233         glob_t glob_result;                     /* result of parameter globbing */
 234         int is_stopped;                         /* is the program currently running? */
 235         struct pipe *family;            /* pointer back to the child's parent pipe */
 236 #endif
 237         int sp;                         /* number of SPECIAL_VAR_SYMBOL */
 238         int type;
 239 };
 240
 241 struct pipe {
 242 #ifndef __U_BOOT__
 243         int jobid;                                      /* job number */
 244 #endif
 245         int num_progs;                          /* total number of programs in job */
 246 #ifndef __U_BOOT__
 247         int running_progs;                      /* number of programs running */
 248         char *text;                                     /* name of job */
 249         char *cmdbuf;                           /* buffer various argv's point into */
 250         pid_t pgrp;                                     /* process group ID for the job */
 251 #endif
 252         struct child_prog *progs;       /* array of commands in pipe */
 253         struct pipe *next;                      /* to track background commands */
 254 #ifndef __U_BOOT__
 255         int stopped_progs;                      /* number of programs alive, but stopped */
 256         int job_context;                        /* bitmask defining current context */
 257 #endif
 258         pipe_style followup;            /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
 259         reserved_style r_mode;          /* supports if, for, while, until */
 260 };
 261
 262 #ifndef __U_BOOT__
 263 struct close_me {
 264         int fd;
 265         struct close_me *next;
 266 };
 267 #endif
 268
 269 struct variables {
 270         char *name;
 271         char *value;
 272         int flg_export;
 273         int flg_read_only;
 274         struct variables *next;
 275 };
 276
 277 /* globals, connect us to the outside world
 278  * the first three support $?, $#, and $1 */
 279 #ifndef __U_BOOT__
 280 char **global_argv;
 281 unsigned int global_argc;
 282 #endif
 283 static unsigned int last_return_code;
 284 #ifndef __U_BOOT__
 285 extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
 286 #endif
 287
 288 /* "globals" within this file */
 289 static uchar *ifs;
 290 static char map[256];
 291 #ifndef __U_BOOT__
 292 static int fake_mode;
 293 static int interactive;
 294 static struct close_me *close_me_head;
 295 static const char *cwd;
 296 static struct pipe *job_list;
 297 static unsigned int last_bg_pid;
 298 static unsigned int last_jobid;
 299 static unsigned int shell_terminal;
 300 static char *PS1;
 301 static char *PS2;
 302 struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
 303 struct variables *top_vars = &shell_ver;
 304 #else
 305 static int flag_repeat = 0;
 306 static int do_repeat = 0;
 307 static struct variables *top_vars = NULL ;
 308 #endif /*__U_BOOT__ */
 309
 310 #define B_CHUNK (100)
 311 #define B_NOSPAC 1
 312
 313 typedef struct {
 314         char *data;
 315         int length;
 316         int maxlen;
 317         int quote;
 318         int nonnull;
 319 } o_string;
 320 #define NULL_O_STRING {NULL,0,0,0,0}
 321 /* used for initialization:
 322         o_string foo = NULL_O_STRING; */
 323
 324 /* I can almost use ordinary FILE *.  Is open_memstream() universally
 325  * available?  Where is it documented? */
 326 struct in_str {
 327         const char *p;
 328 #ifndef __U_BOOT__
 329         char peek_buf[2];
 330 #endif
 331         int __promptme;
 332         int promptmode;
 333 #ifndef __U_BOOT__
 334         FILE *file;
 335 #endif
 336         int (*get) (struct in_str *);
 337         int (*peek) (struct in_str *);
 338 };
 339 #define b_getch(input) ((input)->get(input))
 340 #define b_peek(input) ((input)->peek(input))
 341
 342 #ifndef __U_BOOT__
 343 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
 344
 345 struct built_in_command {
 346         char *cmd;                                      /* name */
 347         char *descr;                            /* description */
 348         int (*function) (struct child_prog *);  /* function ptr */
 349 };
 350 #endif
 351
 352 /* define DEBUG_SHELL for debugging output (obviously ;-)) */
 353 #if 0
 354 #define DEBUG_SHELL
 355 #endif
 356
 357 /* This should be in utility.c */
 358 #ifdef DEBUG_SHELL
 359 #ifndef __U_BOOT__
 360 static void debug_printf(const char *format, ...)
 361 {
 362         va_list args;
 363         va_start(args, format);
 364         vfprintf(stderr, format, args);
 365         va_end(args);
 366 }
 367 #else
 368 #define debug_printf(fmt,args...)       printf (fmt ,##args)
 369 #endif
 370 #else
 371 static inline void debug_printf(const char *format, ...) { }
 372 #endif
 373 #define final_printf debug_printf
 374
 375 #ifdef __U_BOOT__
 376 static void syntax_err(void) {
 377          printf("syntax error\n");
 378 }
 379 #else
 380 static void __syntax(char *file, int line) {
 381         error_msg("syntax error %s:%d", file, line);
 382 }
 383 #define syntax() __syntax(__FILE__, __LINE__)
 384 #endif
 385
 386 #ifdef __U_BOOT__
 387 static void *xmalloc(size_t size);
 388 static void *xrealloc(void *ptr, size_t size);
 389 #else
 390 /* Index of subroutines: */
 391 /*   function prototypes for builtins */
 392 static int builtin_cd(struct child_prog *child);
 393 static int builtin_env(struct child_prog *child);
 394 static int builtin_eval(struct child_prog *child);
 395 static int builtin_exec(struct child_prog *child);
 396 static int builtin_exit(struct child_prog *child);
 397 static int builtin_export(struct child_prog *child);
 398 static int builtin_fg_bg(struct child_prog *child);
 399 static int builtin_help(struct child_prog *child);
 400 static int builtin_jobs(struct child_prog *child);
 401 static int builtin_pwd(struct child_prog *child);
 402 static int builtin_read(struct child_prog *child);
 403 static int builtin_set(struct child_prog *child);
 404 static int builtin_shift(struct child_prog *child);
 405 static int builtin_source(struct child_prog *child);
 406 static int builtin_umask(struct child_prog *child);
 407 static int builtin_unset(struct child_prog *child);
 408 static int builtin_not_written(struct child_prog *child);
 409 #endif
 410 /*   o_string manipulation: */
 411 static int b_check_space(o_string *o, int len);
 412 static int b_addchr(o_string *o, int ch);
 413 static void b_reset(o_string *o);
 414 static int b_addqchr(o_string *o, int ch, int quote);
 415 #ifndef __U_BOOT__
 416 static int b_adduint(o_string *o, unsigned int i);
 417 #endif
 418 /*  in_str manipulations: */
 419 static int static_get(struct in_str *i);
 420 static int static_peek(struct in_str *i);
 421 static int file_get(struct in_str *i);
 422 static int file_peek(struct in_str *i);
 423 #ifndef __U_BOOT__
 424 static void setup_file_in_str(struct in_str *i, FILE *f);
 425 #else
 426 static void setup_file_in_str(struct in_str *i);
 427 #endif
 428 static void setup_string_in_str(struct in_str *i, const char *s);
 429 #ifndef __U_BOOT__
 430 /*  close_me manipulations: */
 431 static void mark_open(int fd);
 432 static void mark_closed(int fd);
 433 static void close_all(void);
 434 #endif
 435 /*  "run" the final data structures: */
 436 static char *indenter(int i);
 437 static int free_pipe_list(struct pipe *head, int indent);
 438 static int free_pipe(struct pipe *pi, int indent);
 439 /*  really run the final data structures: */
 440 #ifndef __U_BOOT__
 441 static int setup_redirects(struct child_prog *prog, int squirrel[]);
 442 #endif
 443 static int run_list_real(struct pipe *pi);
 444 #ifndef __U_BOOT__
 445 static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
 446 #endif
 447 static int run_pipe_real(struct pipe *pi);
 448 /*   extended glob support: */
 449 #ifndef __U_BOOT__
 450 static int globhack(const char *src, int flags, glob_t *pglob);
 451 static int glob_needed(const char *s);
 452 static int xglob(o_string *dest, int flags, glob_t *pglob);
 453 #endif
 454 /*   variable assignment: */
 455 static int is_assignment(const char *s);
 456 /*   data structure manipulation: */
 457 #ifndef __U_BOOT__
 458 static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
 459 #endif
 460 static void initialize_context(struct p_context *ctx);
 461 static int done_word(o_string *dest, struct p_context *ctx);
 462 static int done_command(struct p_context *ctx);
 463 static int done_pipe(struct p_context *ctx, pipe_style type);
 464 /*   primary string parsing: */
 465 #ifndef __U_BOOT__
 466 static int redirect_dup_num(struct in_str *input);
 467 static int redirect_opt_num(o_string *o);
 468 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
 469 static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
 470 #endif
 471 static char *lookup_param(char *src);
 472 static char *make_string(char **inp, int *nonnull);
 473 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
 474 #ifndef __U_BOOT__
 475 static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
 476 #endif
 477 static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
 478 /*   setup: */
 479 static int parse_stream_outer(struct in_str *inp, int flag);
 480 #ifndef __U_BOOT__
 481 static int parse_string_outer(const char *s, int flag);
 482 static int parse_file_outer(FILE *f);
 483 #endif
 484 #ifndef __U_BOOT__
 485 /*   job management: */
 486 static int checkjobs(struct pipe* fg_pipe);
 487 static void insert_bg_job(struct pipe *pi);
 488 static void remove_bg_job(struct pipe *pi);
 489 #endif
 490 /*     local variable support */
 491 static char **make_list_in(char **inp, char *name);
 492 static char *insert_var_value(char *inp);
 493 static char *insert_var_value_sub(char *inp, int tag_subst);
 494
 495 #ifndef __U_BOOT__
 496 /* Table of built-in functions.  They can be forked or not, depending on
 497  * context: within pipes, they fork.  As simple commands, they do not.
 498  * When used in non-forking context, they can change global variables
 499  * in the parent shell process.  If forked, of course they can not.
 500  * For example, 'unset foo | whatever' will parse and run, but foo will
 501  * still be set at the end. */
 502 static struct built_in_command bltins[] = {
 503         {"bg", "Resume a job in the background", builtin_fg_bg},
 504         {"break", "Exit for, while or until loop", builtin_not_written},
 505         {"cd", "Change working directory", builtin_cd},
 506         {"continue", "Continue for, while or until loop", builtin_not_written},
 507         {"env", "Print all environment variables", builtin_env},
 508         {"eval", "Construct and run shell command", builtin_eval},
 509         {"exec", "Exec command, replacing this shell with the exec'd process",
 510                 builtin_exec},
 511         {"exit", "Exit from shell()", builtin_exit},
 512         {"export", "Set environment variable", builtin_export},
 513         {"fg", "Bring job into the foreground", builtin_fg_bg},
 514         {"jobs", "Lists the active jobs", builtin_jobs},
 515         {"pwd", "Print current directory", builtin_pwd},
 516         {"read", "Input environment variable", builtin_read},
 517         {"return", "Return from a function", builtin_not_written},
 518         {"set", "Set/unset shell local variables", builtin_set},
 519         {"shift", "Shift positional parameters", builtin_shift},
 520         {"trap", "Trap signals", builtin_not_written},
 521         {"ulimit","Controls resource limits", builtin_not_written},
 522         {"umask","Sets file creation mask", builtin_umask},
 523         {"unset", "Unset environment variable", builtin_unset},
 524         {".", "Source-in and run commands in a file", builtin_source},
 525         {"help", "List shell built-in commands", builtin_help},
 526         {NULL, NULL, NULL}
 527 };
 528
 529 static const char *set_cwd(void)
 530 {
 531         if(cwd==unknown)
 532                 cwd = NULL;     /* xgetcwd(arg) called free(arg) */
 533         cwd = xgetcwd((char *)cwd);
 534         if (!cwd)
 535                 cwd = unknown;
 536         return cwd;
 537 }
 538
 539 /* built-in 'eval' handler */
 540 static int builtin_eval(struct child_prog *child)
 541 {
 542         char *str = NULL;
 543         int rcode = EXIT_SUCCESS;
 544
 545         if (child->argv[1]) {
 546                 str = make_string(child->argv + 1);
 547                 parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
 548                                         FLAG_PARSE_SEMICOLON);
 549                 free(str);
 550                 rcode = last_return_code;
 551         }
 552         return rcode;
 553 }
 554
 555 /* built-in 'cd <path>' handler */
 556 static int builtin_cd(struct child_prog *child)
 557 {
 558         char *newdir;
 559         if (child->argv[1] == NULL)
 560                 newdir = env_get("HOME");
 561         else
 562                 newdir = child->argv[1];
 563         if (chdir(newdir)) {
 564                 printf("cd: %s: %s\n", newdir, strerror(errno));
 565                 return EXIT_FAILURE;
 566         }
 567         set_cwd();
 568         return EXIT_SUCCESS;
 569 }
 570
 571 /* built-in 'env' handler */
 572 static int builtin_env(struct child_prog *dummy)
 573 {
 574         char **e = environ;
 575         if (e == NULL) return EXIT_FAILURE;
 576         for (; *e; e++) {
 577                 puts(*e);
 578         }
 579         return EXIT_SUCCESS;
 580 }
 581
 582 /* built-in 'exec' handler */
 583 static int builtin_exec(struct child_prog *child)
 584 {
 585         if (child->argv[1] == NULL)
 586                 return EXIT_SUCCESS;   /* Really? */
 587         child->argv++;
 588         pseudo_exec(child);
 589         /* never returns */
 590 }
 591
 592 /* built-in 'exit' handler */
 593 static int builtin_exit(struct child_prog *child)
 594 {
 595         if (child->argv[1] == NULL)
 596                 exit(last_return_code);
 597         exit (atoi(child->argv[1]));
 598 }
 599
 600 /* built-in 'export VAR=value' handler */
 601 static int builtin_export(struct child_prog *child)
 602 {
 603         int res = 0;
 604         char *name = child->argv[1];
 605
 606         if (name == NULL) {
 607                 return (builtin_env(child));
 608         }
 609
 610         name = strdup(name);
 611
 612         if(name) {
 613                 char *value = strchr(name, '=');
 614
 615                 if (!value) {
 616                         char *tmp;
 617                         /* They are exporting something without an =VALUE */
 618
 619                         value = get_local_var(name);
 620                         if (value) {
 621                                 size_t ln = strlen(name);
 622
 623                                 tmp = realloc(name, ln+strlen(value)+2);
 624                                 if(tmp==NULL)
 625                                         res = -1;
 626                                 else {
 627                                         sprintf(tmp+ln, "=%s", value);
 628                                         name = tmp;
 629                                 }
 630                         } else {
 631                                 /* bash does not return an error when trying to export
 632                                  * an undefined variable.  Do likewise. */
 633                                 res = 1;
 634                         }
 635                 }
 636         }
 637         if (res<0)
 638                 perror_msg("export");
 639         else if(res==0)
 640                 res = set_local_var(name, 1);
 641         else
 642                 res = 0;
 643         free(name);
 644         return res;
 645 }
 646
 647 /* built-in 'fg' and 'bg' handler */
 648 static int builtin_fg_bg(struct child_prog *child)
 649 {
 650         int i, jobnum;
 651         struct pipe *pi=NULL;
 652
 653         if (!interactive)
 654                 return EXIT_FAILURE;
 655         /* If they gave us no args, assume they want the last backgrounded task */
 656         if (!child->argv[1]) {
 657                 for (pi = job_list; pi; pi = pi->next) {
 658                         if (pi->jobid == last_jobid) {
 659                                 break;
 660                         }
 661                 }
 662                 if (!pi) {
 663                         error_msg("%s: no current job", child->argv[0]);
 664                         return EXIT_FAILURE;
 665                 }
 666         } else {
 667                 if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
 668                         error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
 669                         return EXIT_FAILURE;
 670                 }
 671                 for (pi = job_list; pi; pi = pi->next) {
 672                         if (pi->jobid == jobnum) {
 673                                 break;
 674                         }
 675                 }
 676                 if (!pi) {
 677                         error_msg("%s: %d: no such job", child->argv[0], jobnum);
 678                         return EXIT_FAILURE;
 679                 }
 680         }
 681
 682         if (*child->argv[0] == 'f') {
 683                 /* Put the job into the foreground.  */
 684                 tcsetpgrp(shell_terminal, pi->pgrp);
 685         }
 686
 687         /* Restart the processes in the job */
 688         for (i = 0; i < pi->num_progs; i++)
 689                 pi->progs[i].is_stopped = 0;
 690
 691         if ( (i=kill(- pi->pgrp, SIGCONT)) < 0) {
 692                 if (i == ESRCH) {
 693                         remove_bg_job(pi);
 694                 } else {
 695                         perror_msg("kill (SIGCONT)");
 696                 }
 697         }
 698
 699         pi->stopped_progs = 0;
 700         return EXIT_SUCCESS;
 701 }
 702
 703 /* built-in 'help' handler */
 704 static int builtin_help(struct child_prog *dummy)
 705 {
 706         struct built_in_command *x;
 707
 708         printf("\nBuilt-in commands:\n");
 709         printf("-------------------\n");
 710         for (x = bltins; x->cmd; x++) {
 711                 if (x->descr==NULL)
 712                         continue;
 713                 printf("%s\t%s\n", x->cmd, x->descr);
 714         }
 715         printf("\n\n");
 716         return EXIT_SUCCESS;
 717 }
 718
 719 /* built-in 'jobs' handler */
 720 static int builtin_jobs(struct child_prog *child)
 721 {
 722         struct pipe *job;
 723         char *status_string;
 724
 725         for (job = job_list; job; job = job->next) {
 726                 if (job->running_progs == job->stopped_progs)
 727                         status_string = "Stopped";
 728                 else
 729                         status_string = "Running";
 730
 731                 printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
 732         }
 733         return EXIT_SUCCESS;
 734 }
 735
 736
 737 /* built-in 'pwd' handler */
 738 static int builtin_pwd(struct child_prog *dummy)
 739 {
 740         puts(set_cwd());
 741         return EXIT_SUCCESS;
 742 }
 743
 744 /* built-in 'read VAR' handler */
 745 static int builtin_read(struct child_prog *child)
 746 {
 747         int res;
 748
 749         if (child->argv[1]) {
 750                 char string[BUFSIZ];
 751                 char *var = 0;
 752
 753                 string[0] = 0;  /* In case stdin has only EOF */
 754                 /* read string */
 755                 fgets(string, sizeof(string), stdin);
 756                 chomp(string);
 757                 var = malloc(strlen(child->argv[1])+strlen(string)+2);
 758                 if(var) {
 759                         sprintf(var, "%s=%s", child->argv[1], string);
 760                         res = set_local_var(var, 0);
 761                 } else
 762                         res = -1;
 763                 if (res)
 764                         fprintf(stderr, "read: %m\n");
 765                 free(var);      /* So not move up to avoid breaking errno */
 766                 return res;
 767         } else {
 768                 do res=getchar(); while(res!='\n' && res!=EOF);
 769                 return 0;
 770         }
 771 }
 772
 773 /* built-in 'set VAR=value' handler */
 774 static int builtin_set(struct child_prog *child)
 775 {
 776         char *temp = child->argv[1];
 777         struct variables *e;
 778
 779         if (temp == NULL)
 780                 for(e = top_vars; e; e=e->next)
 781                         printf("%s=%s\n", e->name, e->value);
 782         else
 783                 set_local_var(temp, 0);
 784
 785                 return EXIT_SUCCESS;
 786 }
 787
 788
 789 /* Built-in 'shift' handler */
 790 static int builtin_shift(struct child_prog *child)
 791 {
 792         int n=1;
 793         if (child->argv[1]) {
 794                 n=atoi(child->argv[1]);
 795         }
 796         if (n>=0 && n<global_argc) {
 797                 /* XXX This probably breaks $0 */
 798                 global_argc -= n;
 799                 global_argv += n;
 800                 return EXIT_SUCCESS;
 801         } else {
 802                 return EXIT_FAILURE;
 803         }
 804 }
 805
 806 /* Built-in '.' handler (read-in and execute commands from file) */
 807 static int builtin_source(struct child_prog *child)
 808 {
 809         FILE *input;
 810         int status;
 811
 812         if (child->argv[1] == NULL)
 813                 return EXIT_FAILURE;
 814
 815         /* XXX search through $PATH is missing */
 816         input = fopen(child->argv[1], "r");
 817         if (!input) {
 818                 error_msg("Couldn't open file '%s'", child->argv[1]);
 819                 return EXIT_FAILURE;
 820         }
 821
 822         /* Now run the file */
 823         /* XXX argv and argc are broken; need to save old global_argv
 824          * (pointer only is OK!) on this stack frame,
 825          * set global_argv=child->argv+1, recurse, and restore. */
 826         mark_open(fileno(input));
 827         status = parse_file_outer(input);
 828         mark_closed(fileno(input));
 829         fclose(input);
 830         return (status);
 831 }
 832
 833 static int builtin_umask(struct child_prog *child)
 834 {
 835         mode_t new_umask;
 836         const char *arg = child->argv[1];
 837         char *end;
 838         if (arg) {
 839                 new_umask=strtoul(arg, &end, 8);
 840                 if (*end!='\0' || end == arg) {
 841                         return EXIT_FAILURE;
 842                 }
 843         } else {
 844                 printf("%.3o\n", (unsigned int) (new_umask=umask(0)));
 845         }
 846         umask(new_umask);
 847         return EXIT_SUCCESS;
 848 }
 849
 850 /* built-in 'unset VAR' handler */
 851 static int builtin_unset(struct child_prog *child)
 852 {
 853         /* bash returned already true */
 854         unset_local_var(child->argv[1]);
 855         return EXIT_SUCCESS;
 856 }
 857
 858 static int builtin_not_written(struct child_prog *child)
 859 {
 860         printf("builtin_%s not written\n",child->argv[0]);
 861         return EXIT_FAILURE;
 862 }
 863 #endif
 864
 865 static int b_check_space(o_string *o, int len)
 866 {
 867         /* It would be easy to drop a more restrictive policy
 868          * in here, such as setting a maximum string length */
 869         if (o->length + len > o->maxlen) {
 870                 char *old_data = o->data;
 871                 /* assert (data == NULL || o->maxlen != 0); */
 872                 o->maxlen += max(2*len, B_CHUNK);
 873                 o->data = realloc(o->data, 1 + o->maxlen);
 874                 if (o->data == NULL) {
 875                         free(old_data);
 876                 }
 877         }
 878         return o->data == NULL;
 879 }
 880
 881 static int b_addchr(o_string *o, int ch)
 882 {
 883         debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
 884         if (b_check_space(o, 1)) return B_NOSPAC;
 885         o->data[o->length] = ch;
 886         o->length++;
 887         o->data[o->length] = '\0';
 888         return 0;
 889 }
 890
 891 static void b_reset(o_string *o)
 892 {
 893         o->length = 0;
 894         o->nonnull = 0;
 895         if (o->data != NULL) *o->data = '\0';
 896 }
 897
 898 static void b_free(o_string *o)
 899 {
 900         b_reset(o);
 901         free(o->data);
 902         o->data = NULL;
 903         o->maxlen = 0;
 904 }
 905
 906 /* My analysis of quoting semantics tells me that state information
 907  * is associated with a destination, not a source.
 908  */
 909 static int b_addqchr(o_string *o, int ch, int quote)
 910 {
 911         if (quote && strchr("*?[\\",ch)) {
 912                 int rc;
 913                 rc = b_addchr(o, '\\');
 914                 if (rc) return rc;
 915         }
 916         return b_addchr(o, ch);
 917 }
 918
 919 #ifndef __U_BOOT__
 920 static int b_adduint(o_string *o, unsigned int i)
 921 {
 922         int r;
 923         char *p = simple_itoa(i);
 924         /* no escape checking necessary */
 925         do r=b_addchr(o, *p++); while (r==0 && *p);
 926         return r;
 927 }
 928 #endif
 929
 930 static int static_get(struct in_str *i)
 931 {
 932         int ch = *i->p++;
 933         if (ch=='\0') return EOF;
 934         return ch;
 935 }
 936
 937 static int static_peek(struct in_str *i)
 938 {
 939         return *i->p;
 940 }
 941
 942 #ifndef __U_BOOT__
 943 static inline void cmdedit_set_initial_prompt(void)
 944 {
 945 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
 946         PS1 = NULL;
 947 #else
 948         PS1 = env_get("PS1");
 949         if(PS1==0)
 950                 PS1 = "\\w \\$ ";
 951 #endif
 952 }
 953
 954 static inline void setup_prompt_string(int promptmode, char **prompt_str)
 955 {
 956         debug_printf("setup_prompt_string %d ",promptmode);
 957 #ifndef CONFIG_FEATURE_SH_FANCY_PROMPT
 958         /* Set up the prompt */
 959         if (promptmode == 1) {
 960                 free(PS1);
 961                 PS1=xmalloc(strlen(cwd)+4);
 962                 sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ?  "$ ":"# ");
 963                 *prompt_str = PS1;
 964         } else {
 965                 *prompt_str = PS2;
 966         }
 967 #else
 968         *prompt_str = (promptmode==1)? PS1 : PS2;
 969 #endif
 970         debug_printf("result %s\n",*prompt_str);
 971 }
 972 #endif
 973
 974 #ifdef __U_BOOT__
 975 static int uboot_cli_readline(struct in_str *i)
 976 {
 977         char *prompt;
 978         char __maybe_unused *ps_prompt = NULL;
 979
 980         if (i->promptmode == 1)
 981                 prompt = CONFIG_SYS_PROMPT;
 982         else
 983                 prompt = CONFIG_SYS_PROMPT_HUSH_PS2;
 984
 985 #ifdef CONFIG_CMDLINE_PS_SUPPORT
 986         if (i->promptmode == 1)
 987                 ps_prompt = env_get("PS1");
 988         else
 989                 ps_prompt = env_get("PS2");
 990         if (ps_prompt)
 991                 prompt = ps_prompt;
 992 #endif
 993
 994         return cli_readline(prompt);
 995 }
 996 #endif
 997
 998 static void get_user_input(struct in_str *i)
 999 {
1000 #ifndef __U_BOOT__
1001         char *prompt_str;
1002         static char the_command[BUFSIZ];
1003
1004         setup_prompt_string(i->promptmode, &prompt_str);
1005 #ifdef CONFIG_FEATURE_COMMAND_EDITING
1006         /*
1007          ** enable command line editing only while a command line
1008          ** is actually being read; otherwise, we'll end up bequeathing
1009          ** atexit() handlers and other unwanted stuff to our
1010          ** child processes (rob@sysgo.de)
1011          */
1012         cmdedit_read_input(prompt_str, the_command);
1013 #else
1014         fputs(prompt_str, stdout);
1015         fflush(stdout);
1016         the_command[0]=fgetc(i->file);
1017         the_command[1]='\0';
1018 #endif
1019         fflush(stdout);
1020         i->p = the_command;
1021 #else
1022         int n;
1023         static char the_command[CONFIG_SYS_CBSIZE + 1];
1024
1025         bootretry_reset_cmd_timeout();
1026         i->__promptme = 1;
1027         n = uboot_cli_readline(i);
1028
1029 #ifdef CONFIG_BOOT_RETRY_TIME
1030         if (n == -2) {
1031           puts("\nTimeout waiting for command\n");
1032 #  ifdef CONFIG_RESET_TO_RETRY
1033           do_reset(NULL, 0, 0, NULL);
1034 #  else
1035 #       error "This currently only works with CONFIG_RESET_TO_RETRY enabled"
1036 #  endif
1037         }
1038 #endif
1039         if (n == -1 ) {
1040                 flag_repeat = 0;
1041                 i->__promptme = 0;
1042         }
1043         n = strlen(console_buffer);
1044         console_buffer[n] = '\n';
1045         console_buffer[n+1]= '\0';
1046         if (had_ctrlc()) flag_repeat = 0;
1047         clear_ctrlc();
1048         do_repeat = 0;
1049         if (i->promptmode == 1) {
1050                 if (console_buffer[0] == '\n'&& flag_repeat == 0) {
1051                         strcpy(the_command,console_buffer);
1052                 }
1053                 else {
1054                         if (console_buffer[0] != '\n') {
1055                                 strcpy(the_command,console_buffer);
1056                                 flag_repeat = 1;
1057                         }
1058                         else {
1059                                 do_repeat = 1;
1060                         }
1061                 }
1062                 i->p = the_command;
1063         }
1064         else {
1065                 if (console_buffer[0] != '\n') {
1066                         if (strlen(the_command) + strlen(console_buffer)
1067                             < CONFIG_SYS_CBSIZE) {
1068                                 n = strlen(the_command);
1069                                 the_command[n-1] = ' ';
1070                                 strcpy(&the_command[n],console_buffer);
1071                         }
1072                         else {
1073                                 the_command[0] = '\n';
1074                                 the_command[1] = '\0';
1075                                 flag_repeat = 0;
1076                         }
1077                 }
1078                 if (i->__promptme == 0) {
1079                         the_command[0] = '\n';
1080                         the_command[1] = '\0';
1081                 }
1082                 i->p = console_buffer;
1083         }
1084 #endif
1085 }
1086
1087 /* This is the magic location that prints prompts
1088  * and gets data back from the user */
1089 static int file_get(struct in_str *i)
1090 {
1091         int ch;
1092
1093         ch = 0;
1094         /* If there is data waiting, eat it up */
1095         if (i->p && *i->p) {
1096                 ch = *i->p++;
1097         } else {
1098                 /* need to double check i->file because we might be doing something
1099                  * more complicated by now, like sourcing or substituting. */
1100 #ifndef __U_BOOT__
1101                 if (i->__promptme && interactive && i->file == stdin) {
1102                         while(! i->p || (interactive && strlen(i->p)==0) ) {
1103 #else
1104                         while(! i->p  || strlen(i->p)==0 ) {
1105 #endif
1106                                 get_user_input(i);
1107                         }
1108                         i->promptmode=2;
1109 #ifndef __U_BOOT__
1110                         i->__promptme = 0;
1111 #endif
1112                         if (i->p && *i->p) {
1113                                 ch = *i->p++;
1114                         }
1115 #ifndef __U_BOOT__
1116                 } else {
1117                         ch = fgetc(i->file);
1118                 }
1119
1120 #endif
1121                 debug_printf("b_getch: got a %d\n", ch);
1122         }
1123 #ifndef __U_BOOT__
1124         if (ch == '\n') i->__promptme=1;
1125 #endif
1126         return ch;
1127 }
1128
1129 /* All the callers guarantee this routine will never be
1130  * used right after a newline, so prompting is not needed.
1131  */
1132 static int file_peek(struct in_str *i)
1133 {
1134 #ifndef __U_BOOT__
1135         if (i->p && *i->p) {
1136 #endif
1137                 return *i->p;
1138 #ifndef __U_BOOT__
1139         } else {
1140                 i->peek_buf[0] = fgetc(i->file);
1141                 i->peek_buf[1] = '\0';
1142                 i->p = i->peek_buf;
1143                 debug_printf("b_peek: got a %d\n", *i->p);
1144                 return *i->p;
1145         }
1146 #endif
1147 }
1148
1149 #ifndef __U_BOOT__
1150 static void setup_file_in_str(struct in_str *i, FILE *f)
1151 #else
1152 static void setup_file_in_str(struct in_str *i)
1153 #endif
1154 {
1155         i->peek = file_peek;
1156         i->get = file_get;
1157         i->__promptme=1;
1158         i->promptmode=1;
1159 #ifndef __U_BOOT__
1160         i->file = f;
1161 #endif
1162         i->p = NULL;
1163 }
1164
1165 static void setup_string_in_str(struct in_str *i, const char *s)
1166 {
1167         i->peek = static_peek;
1168         i->get = static_get;
1169         i->__promptme=1;
1170         i->promptmode=1;
1171         i->p = s;
1172 }
1173
1174 #ifndef __U_BOOT__
1175 static void mark_open(int fd)
1176 {
1177         struct close_me *new = xmalloc(sizeof(struct close_me));
1178         new->fd = fd;
1179         new->next = close_me_head;
1180         close_me_head = new;
1181 }
1182
1183 static void mark_closed(int fd)
1184 {
1185         struct close_me *tmp;
1186         if (close_me_head == NULL || close_me_head->fd != fd)
1187                 error_msg_and_die("corrupt close_me");
1188         tmp = close_me_head;
1189         close_me_head = close_me_head->next;
1190         free(tmp);
1191 }
1192
1193 static void close_all(void)
1194 {
1195         struct close_me *c;
1196         for (c=close_me_head; c; c=c->next) {
1197                 close(c->fd);
1198         }
1199         close_me_head = NULL;
1200 }
1201
1202 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
1203  * and stderr if they are redirected. */
1204 static int setup_redirects(struct child_prog *prog, int squirrel[])
1205 {
1206         int openfd, mode;
1207         struct redir_struct *redir;
1208
1209         for (redir=prog->redirects; redir; redir=redir->next) {
1210                 if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
1211                         /* something went wrong in the parse.  Pretend it didn't happen */
1212                         continue;
1213                 }
1214                 if (redir->dup == -1) {
1215                         mode=redir_table[redir->type].mode;
1216                         openfd = open(redir->word.gl_pathv[0], mode, 0666);
1217                         if (openfd < 0) {
1218                         /* this could get lost if stderr has been redirected, but
1219                            bash and ash both lose it as well (though zsh doesn't!) */
1220                                 perror_msg("error opening %s", redir->word.gl_pathv[0]);
1221                                 return 1;
1222                         }
1223                 } else {
1224                         openfd = redir->dup;
1225                 }
1226
1227                 if (openfd != redir->fd) {
1228                         if (squirrel && redir->fd < 3) {
1229                                 squirrel[redir->fd] = dup(redir->fd);
1230                         }
1231                         if (openfd == -3) {
1232                                 close(openfd);
1233                         } else {
1234                                 dup2(openfd, redir->fd);
1235                                 if (redir->dup == -1)
1236                                         close (openfd);
1237                         }
1238                 }
1239         }
1240         return 0;
1241 }
1242
1243 static void restore_redirects(int squirrel[])
1244 {
1245         int i, fd;
1246         for (i=0; i<3; i++) {
1247                 fd = squirrel[i];
1248                 if (fd != -1) {
1249                         /* No error checking.  I sure wouldn't know what
1250                          * to do with an error if I found one! */
1251                         dup2(fd, i);
1252                         close(fd);
1253                 }
1254         }
1255 }
1256
1257 /* never returns */
1258 /* XXX no exit() here.  If you don't exec, use _exit instead.
1259  * The at_exit handlers apparently confuse the calling process,
1260  * in particular stdin handling.  Not sure why? */
1261 static void pseudo_exec(struct child_prog *child)
1262 {
1263         int i, rcode;
1264         char *p;
1265         struct built_in_command *x;
1266         if (child->argv) {
1267                 for (i=0; is_assignment(child->argv[i]); i++) {
1268                         debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]);
1269                         p = insert_var_value(child->argv[i]);
1270                         putenv(strdup(p));
1271                         if (p != child->argv[i]) free(p);
1272                 }
1273                 child->argv+=i;  /* XXX this hack isn't so horrible, since we are about
1274                                         to exit, and therefore don't need to keep data
1275                                         structures consistent for free() use. */
1276                 /* If a variable is assigned in a forest, and nobody listens,
1277                  * was it ever really set?
1278                  */
1279                 if (child->argv[0] == NULL) {
1280                         _exit(EXIT_SUCCESS);
1281                 }
1282
1283                 /*
1284                  * Check if the command matches any of the builtins.
1285                  * Depending on context, this might be redundant.  But it's
1286                  * easier to waste a few CPU cycles than it is to figure out
1287                  * if this is one of those cases.
1288                  */
1289                 for (x = bltins; x->cmd; x++) {
1290                         if (strcmp(child->argv[0], x->cmd) == 0 ) {
1291                                 debug_printf("builtin exec %s\n", child->argv[0]);
1292                                 rcode = x->function(child);
1293                                 fflush(stdout);
1294                                 _exit(rcode);
1295                         }
1296                 }
1297
1298                 /* Check if the command matches any busybox internal commands
1299                  * ("applets") here.
1300                  * FIXME: This feature is not 100% safe, since
1301                  * BusyBox is not fully reentrant, so we have no guarantee the things
1302                  * from the .bss are still zeroed, or that things from .data are still
1303                  * at their defaults.  We could exec ourself from /proc/self/exe, but I
1304                  * really dislike relying on /proc for things.  We could exec ourself
1305                  * from global_argv[0], but if we are in a chroot, we may not be able
1306                  * to find ourself... */
1307 #ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
1308                 {
1309                         int argc_l;
1310                         char** argv_l=child->argv;
1311                         char *name = child->argv[0];
1312
1313 #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
1314                         /* Following discussions from November 2000 on the busybox mailing
1315                          * list, the default configuration, (without
1316                          * get_last_path_component()) lets the user force use of an
1317                          * external command by specifying the full (with slashes) filename.
1318                          * If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN then applets
1319                          * _aways_ override external commands, so if you want to run
1320                          * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the
1321                          * filesystem and is _not_ busybox.  Some systems may want this,
1322                          * most do not.  */
1323                         name = get_last_path_component(name);
1324 #endif
1325                         /* Count argc for use in a second... */
1326                         for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
1327                         optind = 1;
1328                         debug_printf("running applet %s\n", name);
1329                         run_applet_by_name(name, argc_l, child->argv);
1330                 }
1331 #endif
1332                 debug_printf("exec of %s\n",child->argv[0]);
1333                 execvp(child->argv[0],child->argv);
1334                 perror_msg("couldn't exec: %s",child->argv[0]);
1335                 _exit(1);
1336         } else if (child->group) {
1337                 debug_printf("runtime nesting to group\n");
1338                 interactive=0;    /* crucial!!!! */
1339                 rcode = run_list_real(child->group);
1340                 /* OK to leak memory by not calling free_pipe_list,
1341                  * since this process is about to exit */
1342                 _exit(rcode);
1343         } else {
1344                 /* Can happen.  See what bash does with ">foo" by itself. */
1345                 debug_printf("trying to pseudo_exec null command\n");
1346                 _exit(EXIT_SUCCESS);
1347         }
1348 }
1349
1350 static void insert_bg_job(struct pipe *pi)
1351 {
1352         struct pipe *thejob;
1353
1354         /* Linear search for the ID of the job to use */
1355         pi->jobid = 1;
1356         for (thejob = job_list; thejob; thejob = thejob->next)
1357                 if (thejob->jobid >= pi->jobid)
1358                         pi->jobid = thejob->jobid + 1;
1359
1360         /* add thejob to the list of running jobs */
1361         if (!job_list) {
1362                 thejob = job_list = xmalloc(sizeof(*thejob));
1363         } else {
1364                 for (thejob = job_list; thejob->next; thejob = thejob->next) /* nothing */;
1365                 thejob->next = xmalloc(sizeof(*thejob));
1366                 thejob = thejob->next;
1367         }
1368
1369         /* physically copy the struct job */
1370         memcpy(thejob, pi, sizeof(struct pipe));
1371         thejob->next = NULL;
1372         thejob->running_progs = thejob->num_progs;
1373         thejob->stopped_progs = 0;
1374         thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
1375
1376         /*if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) */
1377         {
1378                 char *bar=thejob->text;
1379                 char **foo=pi->progs[0].argv;
1380                 while(foo && *foo) {
1381                         bar += sprintf(bar, "%s ", *foo++);
1382                 }
1383         }
1384
1385         /* we don't wait for background thejobs to return -- append it
1386            to the list of backgrounded thejobs and leave it alone */
1387         printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
1388         last_bg_pid = thejob->progs[0].pid;
1389         last_jobid = thejob->jobid;
1390 }
1391
1392 /* remove a backgrounded job */
1393 static void remove_bg_job(struct pipe *pi)
1394 {
1395         struct pipe *prev_pipe;
1396
1397         if (pi == job_list) {
1398                 job_list = pi->next;
1399         } else {
1400                 prev_pipe = job_list;
1401                 while (prev_pipe->next != pi)
1402                         prev_pipe = prev_pipe->next;
1403                 prev_pipe->next = pi->next;
1404         }
1405         if (job_list)
1406                 last_jobid = job_list->jobid;
1407         else
1408                 last_jobid = 0;
1409
1410         pi->stopped_progs = 0;
1411         free_pipe(pi, 0);
1412         free(pi);
1413 }
1414
1415 /* Checks to see if any processes have exited -- if they
1416    have, figure out why and see if a job has completed */
1417 static int checkjobs(struct pipe* fg_pipe)
1418 {
1419         int attributes;
1420         int status;
1421         int prognum = 0;
1422         struct pipe *pi;
1423         pid_t childpid;
1424
1425         attributes = WUNTRACED;
1426         if (fg_pipe==NULL) {
1427                 attributes |= WNOHANG;
1428         }
1429
1430         while ((childpid = waitpid(-1, &status, attributes)) > 0) {
1431                 if (fg_pipe) {
1432                         int i, rcode = 0;
1433                         for (i=0; i < fg_pipe->num_progs; i++) {
1434                                 if (fg_pipe->progs[i].pid == childpid) {
1435                                         if (i==fg_pipe->num_progs-1)
1436                                                 rcode=WEXITSTATUS(status);
1437                                         (fg_pipe->num_progs)--;
1438                                         return(rcode);
1439                                 }
1440                         }
1441                 }
1442
1443                 for (pi = job_list; pi; pi = pi->next) {
1444                         prognum = 0;
1445                         while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
1446                                 prognum++;
1447                         }
1448                         if (prognum < pi->num_progs)
1449                                 break;
1450                 }
1451
1452                 if(pi==NULL) {
1453                         debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
1454                         continue;
1455                 }
1456
1457                 if (WIFEXITED(status) || WIFSIGNALED(status)) {
1458                         /* child exited */
1459                         pi->running_progs--;
1460                         pi->progs[prognum].pid = 0;
1461
1462                         if (!pi->running_progs) {
1463                                 printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text);
1464                                 remove_bg_job(pi);
1465                         }
1466                 } else {
1467                         /* child stopped */
1468                         pi->stopped_progs++;
1469                         pi->progs[prognum].is_stopped = 1;
1470
1471 #if 0
1472                         /* Printing this stuff is a pain, since it tends to
1473                          * overwrite the prompt an inconveinient moments.  So
1474                          * don't do that.  */
1475                         if (pi->stopped_progs == pi->num_progs) {
1476                                 printf("\n"JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text);
1477                         }
1478 #endif
1479                 }
1480         }
1481
1482         if (childpid == -1 && errno != ECHILD)
1483                 perror_msg("waitpid");
1484
1485         /* move the shell to the foreground */
1486         /*if (interactive && tcsetpgrp(shell_terminal, getpgid(0))) */
1487         /*      perror_msg("tcsetpgrp-2"); */
1488         return -1;
1489 }
1490
1491 /* Figure out our controlling tty, checking in order stderr,
1492  * stdin, and stdout.  If check_pgrp is set, also check that
1493  * we belong to the foreground process group associated with
1494  * that tty.  The value of shell_terminal is needed in order to call
1495  * tcsetpgrp(shell_terminal, ...); */
1496 void controlling_tty(int check_pgrp)
1497 {
1498         pid_t curpgrp;
1499
1500         if ((curpgrp = tcgetpgrp(shell_terminal = 2)) < 0
1501                         && (curpgrp = tcgetpgrp(shell_terminal = 0)) < 0
1502                         && (curpgrp = tcgetpgrp(shell_terminal = 1)) < 0)
1503                 goto shell_terminal_error;
1504
1505         if (check_pgrp && curpgrp != getpgid(0))
1506                 goto shell_terminal_error;
1507
1508         return;
1509
1510 shell_terminal_error:
1511                 shell_terminal = -1;
1512                 return;
1513 }
1514 #endif
1515
1516 /* run_pipe_real() starts all the jobs, but doesn't wait for anything
1517  * to finish.  See checkjobs().
1518  *
1519  * return code is normally -1, when the caller has to wait for children
1520  * to finish to determine the exit status of the pipe.  If the pipe
1521  * is a simple builtin command, however, the action is done by the
1522  * time run_pipe_real returns, and the exit code is provided as the
1523  * return value.
1524  *
1525  * The input of the pipe is always stdin, the output is always
1526  * stdout.  The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
1527  * because it tries to avoid running the command substitution in
1528  * subshell, when that is in fact necessary.  The subshell process
1529  * now has its stdout directed to the input of the appropriate pipe,
1530  * so this routine is noticeably simpler.
1531  */
1532 static int run_pipe_real(struct pipe *pi)
1533 {
1534         int i;
1535 #ifndef __U_BOOT__
1536         int nextin, nextout;
1537         int pipefds[2];                         /* pipefds[0] is for reading */
1538         struct child_prog *child;
1539         struct built_in_command *x;
1540         char *p;
1541 # if __GNUC__
1542         /* Avoid longjmp clobbering */
1543         (void) &i;
1544         (void) &nextin;
1545         (void) &nextout;
1546         (void) &child;
1547 # endif
1548 #else
1549         int nextin;
1550         int flag = do_repeat ? CMD_FLAG_REPEAT : 0;
1551         struct child_prog *child;
1552         char *p;
1553 # if __GNUC__
1554         /* Avoid longjmp clobbering */
1555         (void) &i;
1556         (void) &nextin;
1557         (void) &child;
1558 # endif
1559 #endif  /* __U_BOOT__ */
1560
1561         nextin = 0;
1562 #ifndef __U_BOOT__
1563         pi->pgrp = -1;
1564 #endif
1565
1566         /* Check if this is a simple builtin (not part of a pipe).
1567          * Builtins within pipes have to fork anyway, and are handled in
1568          * pseudo_exec.  "echo foo | read bar" doesn't work on bash, either.
1569          */
1570         if (pi->num_progs == 1) child = & (pi->progs[0]);
1571 #ifndef __U_BOOT__
1572         if (pi->num_progs == 1 && child->group && child->subshell == 0) {
1573                 int squirrel[] = {-1, -1, -1};
1574                 int rcode;
1575                 debug_printf("non-subshell grouping\n");
1576                 setup_redirects(child, squirrel);
1577                 /* XXX could we merge code with following builtin case,
1578                  * by creating a pseudo builtin that calls run_list_real? */
1579                 rcode = run_list_real(child->group);
1580                 restore_redirects(squirrel);
1581 #else
1582                 if (pi->num_progs == 1 && child->group) {
1583                 int rcode;
1584                 debug_printf("non-subshell grouping\n");
1585                 rcode = run_list_real(child->group);
1586 #endif
1587                 return rcode;
1588         } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
1589                 for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
1590                 if (i!=0 && child->argv[i]==NULL) {
1591                         /* assignments, but no command: set the local environment */
1592                         for (i=0; child->argv[i]!=NULL; i++) {
1593
1594                                 /* Ok, this case is tricky.  We have to decide if this is a
1595                                  * local variable, or an already exported variable.  If it is
1596                                  * already exported, we have to export the new value.  If it is
1597                                  * not exported, we need only set this as a local variable.
1598                                  * This junk is all to decide whether or not to export this
1599                                  * variable. */
1600                                 int export_me=0;
1601                                 char *name, *value;
1602                                 name = xstrdup(child->argv[i]);
1603                                 debug_printf("Local environment set: %s\n", name);
1604                                 value = strchr(name, '=');
1605                                 if (value)
1606                                         *value=0;
1607 #ifndef __U_BOOT__
1608                                 if ( get_local_var(name)) {
1609                                         export_me=1;
1610                                 }
1611 #endif
1612                                 free(name);
1613                                 p = insert_var_value(child->argv[i]);
1614                                 set_local_var(p, export_me);
1615                                 if (p != child->argv[i]) free(p);
1616                         }
1617                         return EXIT_SUCCESS;   /* don't worry about errors in set_local_var() yet */
1618                 }
1619                 for (i = 0; is_assignment(child->argv[i]); i++) {
1620                         p = insert_var_value(child->argv[i]);
1621 #ifndef __U_BOOT__
1622                         putenv(strdup(p));
1623 #else
1624                         set_local_var(p, 0);
1625 #endif
1626                         if (p != child->argv[i]) {
1627                                 child->sp--;
1628                                 free(p);
1629                         }
1630                 }
1631                 if (child->sp) {
1632                         char * str = NULL;
1633
1634                         str = make_string(child->argv + i,
1635                                           child->argv_nonnull + i);
1636                         parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
1637                         free(str);
1638                         return last_return_code;
1639                 }
1640 #ifndef __U_BOOT__
1641                 for (x = bltins; x->cmd; x++) {
1642                         if (strcmp(child->argv[i], x->cmd) == 0 ) {
1643                                 int squirrel[] = {-1, -1, -1};
1644                                 int rcode;
1645                                 if (x->function == builtin_exec && child->argv[i+1]==NULL) {
1646                                         debug_printf("magic exec\n");
1647                                         setup_redirects(child,NULL);
1648                                         return EXIT_SUCCESS;
1649                                 }
1650                                 debug_printf("builtin inline %s\n", child->argv[0]);
1651                                 /* XXX setup_redirects acts on file descriptors, not FILEs.
1652                                  * This is perfect for work that comes after exec().
1653                                  * Is it really safe for inline use?  Experimentally,
1654                                  * things seem to work with glibc. */
1655                                 setup_redirects(child, squirrel);
1656
1657                                 child->argv += i;  /* XXX horrible hack */
1658                                 rcode = x->function(child);
1659                                 /* XXX restore hack so free() can work right */
1660                                 child->argv -= i;
1661                                 restore_redirects(squirrel);
1662                         }
1663                         return rcode;
1664                 }
1665 #else
1666                 /* check ";", because ,example , argv consist from
1667                  * "help;flinfo" must not execute
1668                  */
1669                 if (strchr(child->argv[i], ';')) {
1670                         printf("Unknown command '%s' - try 'help' or use "
1671                                         "'run' command\n", child->argv[i]);
1672                         return -1;
1673                 }
1674                 /* Process the command */
1675                 return cmd_process(flag, child->argc - i, child->argv + i,
1676                                    &flag_repeat, NULL);
1677 #endif
1678         }
1679 #ifndef __U_BOOT__
1680
1681         for (i = 0; i < pi->num_progs; i++) {
1682                 child = & (pi->progs[i]);
1683
1684                 /* pipes are inserted between pairs of commands */
1685                 if ((i + 1) < pi->num_progs) {
1686                         if (pipe(pipefds)<0) perror_msg_and_die("pipe");
1687                         nextout = pipefds[1];
1688                 } else {
1689                         nextout=1;
1690                         pipefds[0] = -1;
1691                 }
1692
1693                 /* XXX test for failed fork()? */
1694                 if (!(child->pid = fork())) {
1695                         /* Set the handling for job control signals back to the default.  */
1696                         signal(SIGINT, SIG_DFL);
1697                         signal(SIGQUIT, SIG_DFL);
1698                         signal(SIGTERM, SIG_DFL);
1699                         signal(SIGTSTP, SIG_DFL);
1700                         signal(SIGTTIN, SIG_DFL);
1701                         signal(SIGTTOU, SIG_DFL);
1702                         signal(SIGCHLD, SIG_DFL);
1703
1704                         close_all();
1705
1706                         if (nextin != 0) {
1707                                 dup2(nextin, 0);
1708                                 close(nextin);
1709                         }
1710                         if (nextout != 1) {
1711                                 dup2(nextout, 1);
1712                                 close(nextout);
1713                         }
1714                         if (pipefds[0]!=-1) {
1715                                 close(pipefds[0]);  /* opposite end of our output pipe */
1716                         }
1717
1718                         /* Like bash, explicit redirects override pipes,
1719                          * and the pipe fd is available for dup'ing. */
1720                         setup_redirects(child,NULL);
1721
1722                         if (interactive && pi->followup!=PIPE_BG) {
1723                                 /* If we (the child) win the race, put ourselves in the process
1724                                  * group whose leader is the first process in this pipe. */
1725                                 if (pi->pgrp < 0) {
1726                                         pi->pgrp = getpid();
1727                                 }
1728                                 if (setpgid(0, pi->pgrp) == 0) {
1729                                         tcsetpgrp(2, pi->pgrp);
1730                                 }
1731                         }
1732
1733                         pseudo_exec(child);
1734                 }
1735
1736
1737                 /* put our child in the process group whose leader is the
1738                    first process in this pipe */
1739                 if (pi->pgrp < 0) {
1740                         pi->pgrp = child->pid;
1741                 }
1742                 /* Don't check for errors.  The child may be dead already,
1743                  * in which case setpgid returns error code EACCES. */
1744                 setpgid(child->pid, pi->pgrp);
1745
1746                 if (nextin != 0)
1747                         close(nextin);
1748                 if (nextout != 1)
1749                         close(nextout);
1750
1751                 /* If there isn't another process, nextin is garbage
1752                    but it doesn't matter */
1753                 nextin = pipefds[0];
1754         }
1755 #endif
1756         return -1;
1757 }
1758
1759 static int run_list_real(struct pipe *pi)
1760 {
1761         char *save_name = NULL;
1762         char **list = NULL;
1763         char **save_list = NULL;
1764         struct pipe *rpipe;
1765         int flag_rep = 0;
1766 #ifndef __U_BOOT__
1767         int save_num_progs;
1768 #endif
1769         int rcode=0, flag_skip=1;
1770         int flag_restore = 0;
1771         int if_code=0, next_if_code=0;  /* need double-buffer to handle elif */
1772         reserved_style rmode, skip_more_in_this_rmode=RES_XXXX;
1773         /* check syntax for "for" */
1774         for (rpipe = pi; rpipe; rpipe = rpipe->next) {
1775                 if ((rpipe->r_mode == RES_IN ||
1776                     rpipe->r_mode == RES_FOR) &&
1777                     (rpipe->next == NULL)) {
1778                                 syntax();
1779 #ifdef __U_BOOT__
1780                                 flag_repeat = 0;
1781 #endif
1782                                 return 1;
1783                 }
1784                 if ((rpipe->r_mode == RES_IN &&
1785                         (rpipe->next->r_mode == RES_IN &&
1786                         rpipe->next->progs->argv != NULL))||
1787                         (rpipe->r_mode == RES_FOR &&
1788                         rpipe->next->r_mode != RES_IN)) {
1789                                 syntax();
1790 #ifdef __U_BOOT__
1791                                 flag_repeat = 0;
1792 #endif
1793                                 return 1;
1794                 }
1795         }
1796         for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
1797                 if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
1798                         pi->r_mode == RES_FOR) {
1799 #ifdef __U_BOOT__
1800                                 /* check Ctrl-C */
1801                                 ctrlc();
1802                                 if ((had_ctrlc())) {
1803                                         return 1;
1804                                 }
1805 #endif
1806                                 flag_restore = 0;
1807                                 if (!rpipe) {
1808                                         flag_rep = 0;
1809                                         rpipe = pi;
1810                                 }
1811                 }
1812                 rmode = pi->r_mode;
1813                 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);
1814                 if (rmode == skip_more_in_this_rmode && flag_skip) {
1815                         if (pi->followup == PIPE_SEQ) flag_skip=0;
1816                         continue;
1817                 }
1818                 flag_skip = 1;
1819                 skip_more_in_this_rmode = RES_XXXX;
1820                 if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
1821                 if (rmode == RES_THEN &&  if_code) continue;
1822                 if (rmode == RES_ELSE && !if_code) continue;
1823                 if (rmode == RES_ELIF && !if_code) break;
1824                 if (rmode == RES_FOR && pi->num_progs) {
1825                         if (!list) {
1826                                 /* if no variable values after "in" we skip "for" */
1827                                 if (!pi->next->progs->argv) continue;
1828                                 /* create list of variable values */
1829                                 list = make_list_in(pi->next->progs->argv,
1830                                         pi->progs->argv[0]);
1831                                 save_list = list;
1832                                 save_name = pi->progs->argv[0];
1833                                 pi->progs->argv[0] = NULL;
1834                                 flag_rep = 1;
1835                         }
1836                         if (!(*list)) {
1837                                 free(pi->progs->argv[0]);
1838                                 free(save_list);
1839                                 list = NULL;
1840                                 flag_rep = 0;
1841                                 pi->progs->argv[0] = save_name;
1842 #ifndef __U_BOOT__
1843                                 pi->progs->glob_result.gl_pathv[0] =
1844                                         pi->progs->argv[0];
1845 #endif
1846                                 continue;
1847                         } else {
1848                                 /* insert new value from list for variable */
1849                                 free(pi->progs->argv[0]);
1850                                 pi->progs->argv[0] = *list++;
1851 #ifndef __U_BOOT__
1852                                 pi->progs->glob_result.gl_pathv[0] =
1853                                         pi->progs->argv[0];
1854 #endif
1855                         }
1856                 }
1857                 if (rmode == RES_IN) continue;
1858                 if (rmode == RES_DO) {
1859                         if (!flag_rep) continue;
1860                 }
1861                 if (rmode == RES_DONE) {
1862                         if (flag_rep) {
1863                                 flag_restore = 1;
1864                         } else {
1865                                 rpipe = NULL;
1866                         }
1867                 }
1868                 if (pi->num_progs == 0) continue;
1869 #ifndef __U_BOOT__
1870                 save_num_progs = pi->num_progs; /* save number of programs */
1871 #endif
1872                 rcode = run_pipe_real(pi);
1873                 debug_printf("run_pipe_real returned %d\n",rcode);
1874 #ifndef __U_BOOT__
1875                 if (rcode!=-1) {
1876                         /* We only ran a builtin: rcode was set by the return value
1877                          * of run_pipe_real(), and we don't need to wait for anything. */
1878                 } else if (pi->followup==PIPE_BG) {
1879                         /* XXX check bash's behavior with nontrivial pipes */
1880                         /* XXX compute jobid */
1881                         /* XXX what does bash do with attempts to background builtins? */
1882                         insert_bg_job(pi);
1883                         rcode = EXIT_SUCCESS;
1884                 } else {
1885                         if (interactive) {
1886                                 /* move the new process group into the foreground */
1887                                 if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
1888                                         perror_msg("tcsetpgrp-3");
1889                                 rcode = checkjobs(pi);
1890                                 /* move the shell to the foreground */
1891                                 if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
1892                                         perror_msg("tcsetpgrp-4");
1893                         } else {
1894                                 rcode = checkjobs(pi);
1895                         }
1896                         debug_printf("checkjobs returned %d\n",rcode);
1897                 }
1898                 last_return_code=rcode;
1899 #else
1900                 if (rcode < -1) {
1901                         last_return_code = -rcode - 2;
1902                         return -2;      /* exit */
1903                 }
1904                 last_return_code = rcode;
1905 #endif
1906 #ifndef __U_BOOT__
1907                 pi->num_progs = save_num_progs; /* restore number of programs */
1908 #endif
1909                 if ( rmode == RES_IF || rmode == RES_ELIF )
1910                         next_if_code=rcode;  /* can be overwritten a number of times */
1911                 if (rmode == RES_WHILE)
1912                         flag_rep = !last_return_code;
1913                 if (rmode == RES_UNTIL)
1914                         flag_rep = last_return_code;
1915                 if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
1916                      (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
1917                         skip_more_in_this_rmode=rmode;
1918 #ifndef __U_BOOT__
1919                 checkjobs(NULL);
1920 #endif
1921         }
1922         return rcode;
1923 }
1924
1925 /* broken, of course, but OK for testing */
1926 static char *indenter(int i)
1927 {
1928         static char blanks[]="                                    ";
1929         return &blanks[sizeof(blanks)-i-1];
1930 }
1931
1932 /* return code is the exit status of the pipe */
1933 static int free_pipe(struct pipe *pi, int indent)
1934 {
1935         char **p;
1936         struct child_prog *child;
1937 #ifndef __U_BOOT__
1938         struct redir_struct *r, *rnext;
1939 #endif
1940         int a, i, ret_code=0;
1941         char *ind = indenter(indent);
1942
1943 #ifndef __U_BOOT__
1944         if (pi->stopped_progs > 0)
1945                 return ret_code;
1946         final_printf("%s run pipe: (pid %d)\n",ind,getpid());
1947 #endif
1948         for (i=0; i<pi->num_progs; i++) {
1949                 child = &pi->progs[i];
1950                 final_printf("%s  command %d:\n",ind,i);
1951                 if (child->argv) {
1952                         for (a=0,p=child->argv; *p; a++,p++) {
1953                                 final_printf("%s   argv[%d] = %s\n",ind,a,*p);
1954                         }
1955 #ifndef __U_BOOT__
1956                         globfree(&child->glob_result);
1957 #else
1958                         for (a = 0; a < child->argc; a++) {
1959                                 free(child->argv[a]);
1960                         }
1961                         free(child->argv);
1962                         free(child->argv_nonnull);
1963                         child->argc = 0;
1964 #endif
1965                         child->argv=NULL;
1966                 } else if (child->group) {
1967 #ifndef __U_BOOT__
1968                         final_printf("%s   begin group (subshell:%d)\n",ind, child->subshell);
1969 #endif
1970                         ret_code = free_pipe_list(child->group,indent+3);
1971                         final_printf("%s   end group\n",ind);
1972                 } else {
1973                         final_printf("%s   (nil)\n",ind);
1974                 }
1975 #ifndef __U_BOOT__
1976                 for (r=child->redirects; r; r=rnext) {
1977                         final_printf("%s   redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
1978                         if (r->dup == -1) {
1979                                 /* guard against the case >$FOO, where foo is unset or blank */
1980                                 if (r->word.gl_pathv) {
1981                                         final_printf(" %s\n", *r->word.gl_pathv);
1982                                         globfree(&r->word);
1983                                 }
1984                         } else {
1985                                 final_printf("&%d\n", r->dup);
1986                         }
1987                         rnext=r->next;
1988                         free(r);
1989                 }
1990                 child->redirects=NULL;
1991 #endif
1992         }
1993         free(pi->progs);   /* children are an array, they get freed all at once */
1994         pi->progs=NULL;
1995         return ret_code;
1996 }
1997
1998 static int free_pipe_list(struct pipe *head, int indent)
1999 {
2000         int rcode=0;   /* if list has no members */
2001         struct pipe *pi, *next;
2002         char *ind = indenter(indent);
2003         for (pi=head; pi; pi=next) {
2004                 final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
2005                 rcode = free_pipe(pi, indent);
2006                 final_printf("%s pipe followup code %d\n", ind, pi->followup);
2007                 next=pi->next;
2008                 pi->next=NULL;
2009                 free(pi);
2010         }
2011         return rcode;
2012 }
2013
2014 /* Select which version we will use */
2015 static int run_list(struct pipe *pi)
2016 {
2017         int rcode=0;
2018 #ifndef __U_BOOT__
2019         if (fake_mode==0) {
2020 #endif
2021                 rcode = run_list_real(pi);
2022 #ifndef __U_BOOT__
2023         }
2024 #endif
2025         /* free_pipe_list has the side effect of clearing memory
2026          * In the long run that function can be merged with run_list_real,
2027          * but doing that now would hobble the debugging effort. */
2028         free_pipe_list(pi,0);
2029         return rcode;
2030 }
2031
2032 /* The API for glob is arguably broken.  This routine pushes a non-matching
2033  * string into the output structure, removing non-backslashed backslashes.
2034  * If someone can prove me wrong, by performing this function within the
2035  * original glob(3) api, feel free to rewrite this routine into oblivion.
2036  * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
2037  * XXX broken if the last character is '\\', check that before calling.
2038  */
2039 #ifndef __U_BOOT__
2040 static int globhack(const char *src, int flags, glob_t *pglob)
2041 {
2042         int cnt=0, pathc;
2043         const char *s;
2044         char *dest;
2045         for (cnt=1, s=src; s && *s; s++) {
2046                 if (*s == '\\') s++;
2047                 cnt++;
2048         }
2049         dest = malloc(cnt);
2050         if (!dest) return GLOB_NOSPACE;
2051         if (!(flags & GLOB_APPEND)) {
2052                 pglob->gl_pathv=NULL;
2053                 pglob->gl_pathc=0;
2054                 pglob->gl_offs=0;
2055                 pglob->gl_offs=0;
2056         }
2057         pathc = ++pglob->gl_pathc;
2058         pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
2059         if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
2060         pglob->gl_pathv[pathc-1]=dest;
2061         pglob->gl_pathv[pathc]=NULL;
2062         for (s=src; s && *s; s++, dest++) {
2063                 if (*s == '\\') s++;
2064                 *dest = *s;
2065         }
2066         *dest='\0';
2067         return 0;
2068 }
2069
2070 /* XXX broken if the last character is '\\', check that before calling */
2071 static int glob_needed(const char *s)
2072 {
2073         for (; *s; s++) {
2074                 if (*s == '\\') s++;
2075                 if (strchr("*[?",*s)) return 1;
2076         }
2077         return 0;
2078 }
2079
2080 #if 0
2081 static void globprint(glob_t *pglob)
2082 {
2083         int i;
2084         debug_printf("glob_t at %p:\n", pglob);
2085         debug_printf("  gl_pathc=%d  gl_pathv=%p  gl_offs=%d  gl_flags=%d\n",
2086                 pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
2087         for (i=0; i<pglob->gl_pathc; i++)
2088                 debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
2089                         pglob->gl_pathv[i], pglob->gl_pathv[i]);
2090 }
2091 #endif
2092
2093 static int xglob(o_string *dest, int flags, glob_t *pglob)
2094 {
2095         int gr;
2096
2097         /* short-circuit for null word */
2098         /* we can code this better when the debug_printf's are gone */
2099         if (dest->length == 0) {
2100                 if (dest->nonnull) {
2101                         /* bash man page calls this an "explicit" null */
2102                         gr = globhack(dest->data, flags, pglob);
2103                         debug_printf("globhack returned %d\n",gr);
2104                 } else {
2105                         return 0;
2106                 }
2107         } else if (glob_needed(dest->data)) {
2108                 gr = glob(dest->data, flags, NULL, pglob);
2109                 debug_printf("glob returned %d\n",gr);
2110                 if (gr == GLOB_NOMATCH) {
2111                         /* quote removal, or more accurately, backslash removal */
2112                         gr = globhack(dest->data, flags, pglob);
2113                         debug_printf("globhack returned %d\n",gr);
2114                 }
2115         } else {
2116                 gr = globhack(dest->data, flags, pglob);
2117                 debug_printf("globhack returned %d\n",gr);
2118         }
2119         if (gr == GLOB_NOSPACE)
2120                 error_msg_and_die("out of memory during glob");
2121         if (gr != 0) { /* GLOB_ABORTED ? */
2122                 error_msg("glob(3) error %d",gr);
2123         }
2124         /* globprint(glob_target); */
2125         return gr;
2126 }
2127 #endif
2128
2129 #ifdef __U_BOOT__
2130 static char *get_dollar_var(char ch);
2131 #endif
2132
2133 /* This is used to get/check local shell variables */
2134 char *get_local_var(const char *s)
2135 {
2136         struct variables *cur;
2137
2138         if (!s)
2139                 return NULL;
2140
2141 #ifdef __U_BOOT__
2142         if (*s == '$')
2143                 return get_dollar_var(s[1]);
2144 #endif
2145
2146         for (cur = top_vars; cur; cur=cur->next)
2147                 if(strcmp(cur->name, s)==0)
2148                         return cur->value;
2149         return NULL;
2150 }
2151
2152 /* This is used to set local shell variables
2153    flg_export==0 if only local (not exporting) variable
2154    flg_export==1 if "new" exporting environ
2155    flg_export>1  if current startup environ (not call putenv()) */
2156 int set_local_var(const char *s, int flg_export)
2157 {
2158         char *name, *value;
2159         int result=0;
2160         struct variables *cur;
2161
2162 #ifdef __U_BOOT__
2163         /* might be possible! */
2164         if (!isalpha(*s))
2165                 return -1;
2166 #endif
2167
2168         name=strdup(s);
2169
2170         /* Assume when we enter this function that we are already in
2171          * NAME=VALUE format.  So the first order of business is to
2172          * split 's' on the '=' into 'name' and 'value' */
2173         value = strchr(name, '=');
2174         if (value == NULL || *(value + 1) == 0) {
2175                 free(name);
2176                 return -1;
2177         }
2178         *value++ = 0;
2179
2180         for(cur = top_vars; cur; cur = cur->next) {
2181                 if(strcmp(cur->name, name)==0)
2182                         break;
2183         }
2184
2185         if(cur) {
2186                 if(strcmp(cur->value, value)==0) {
2187                         if(flg_export>0 && cur->flg_export==0)
2188                                 cur->flg_export=flg_export;
2189                         else
2190                                 result++;
2191                 } else {
2192                         if(cur->flg_read_only) {
2193                                 error_msg("%s: readonly variable", name);
2194                                 result = -1;
2195                         } else {
2196                                 if(flg_export>0 || cur->flg_export>1)
2197                                         cur->flg_export=1;
2198                                 free(cur->value);
2199
2200                                 cur->value = strdup(value);
2201                         }
2202                 }
2203         } else {
2204                 cur = malloc(sizeof(struct variables));
2205                 if(!cur) {
2206                         result = -1;
2207                 } else {
2208                         cur->name = strdup(name);
2209                         if (cur->name == NULL) {
2210                                 free(cur);
2211                                 result = -1;
2212                         } else {
2213                                 struct variables *bottom = top_vars;
2214                                 cur->value = strdup(value);
2215                                 cur->next = NULL;
2216                                 cur->flg_export = flg_export;
2217                                 cur->flg_read_only = 0;
2218                                 while(bottom->next) bottom=bottom->next;
2219                                 bottom->next = cur;
2220                         }
2221                 }
2222         }
2223
2224 #ifndef __U_BOOT__
2225         if(result==0 && cur->flg_export==1) {
2226                 *(value-1) = '=';
2227                 result = putenv(name);
2228         } else {
2229 #endif
2230                 free(name);
2231 #ifndef __U_BOOT__
2232                 if(result>0)            /* equivalent to previous set */
2233                         result = 0;
2234         }
2235 #endif
2236         return result;
2237 }
2238
2239 void unset_local_var(const char *name)
2240 {
2241         struct variables *cur;
2242
2243         if (name) {
2244                 for (cur = top_vars; cur; cur=cur->next) {
2245                         if(strcmp(cur->name, name)==0)
2246                                 break;
2247                 }
2248                 if (cur != NULL) {
2249                         struct variables *next = top_vars;
2250                         if(cur->flg_read_only) {
2251                                 error_msg("%s: readonly variable", name);
2252                                 return;
2253                         } else {
2254 #ifndef __U_BOOT__
2255                                 if(cur->flg_export)
2256                                         unenv_set(cur->name);
2257 #endif
2258                                 free(cur->name);
2259                                 free(cur->value);
2260                                 while (next->next != cur)
2261                                         next = next->next;
2262                                 next->next = cur->next;
2263                         }
2264                         free(cur);
2265                 }
2266         }
2267 }
2268
2269 static int is_assignment(const char *s)
2270 {
2271         if (s == NULL)
2272                 return 0;
2273
2274         if (!isalpha(*s)) return 0;
2275         ++s;
2276         while(isalnum(*s) || *s=='_') ++s;
2277         return *s=='=';
2278 }
2279
2280 #ifndef __U_BOOT__
2281 /* the src parameter allows us to peek forward to a possible &n syntax
2282  * for file descriptor duplication, e.g., "2>&1".
2283  * Return code is 0 normally, 1 if a syntax error is detected in src.
2284  * Resource errors (in xmalloc) cause the process to exit */
2285 static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
2286         struct in_str *input)
2287 {
2288         struct child_prog *child=ctx->child;
2289         struct redir_struct *redir = child->redirects;
2290         struct redir_struct *last_redir=NULL;
2291
2292         /* Create a new redir_struct and drop it onto the end of the linked list */
2293         while(redir) {
2294                 last_redir=redir;
2295                 redir=redir->next;
2296         }
2297         redir = xmalloc(sizeof(struct redir_struct));
2298         redir->next=NULL;
2299         redir->word.gl_pathv=NULL;
2300         if (last_redir) {
2301                 last_redir->next=redir;
2302         } else {
2303                 child->redirects=redir;
2304         }
2305
2306         redir->type=style;
2307         redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
2308
2309         debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
2310
2311         /* Check for a '2>&1' type redirect */
2312         redir->dup = redirect_dup_num(input);
2313         if (redir->dup == -2) return 1;  /* syntax error */
2314         if (redir->dup != -1) {
2315                 /* Erik had a check here that the file descriptor in question
2316                  * is legit; I postpone that to "run time"
2317                  * A "-" representation of "close me" shows up as a -3 here */
2318                 debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
2319         } else {
2320                 /* We do _not_ try to open the file that src points to,
2321                  * since we need to return and let src be expanded first.
2322                  * Set ctx->pending_redirect, so we know what to do at the
2323                  * end of the next parsed word.
2324                  */
2325                 ctx->pending_redirect = redir;
2326         }
2327         return 0;
2328 }
2329 #endif
2330
2331 static struct pipe *new_pipe(void)
2332 {
2333         struct pipe *pi;
2334         pi = xmalloc(sizeof(struct pipe));
2335         pi->num_progs = 0;
2336         pi->progs = NULL;
2337         pi->next = NULL;
2338         pi->followup = 0;  /* invalid */
2339         pi->r_mode = RES_NONE;
2340         return pi;
2341 }
2342
2343 static void initialize_context(struct p_context *ctx)
2344 {
2345         ctx->pipe=NULL;
2346 #ifndef __U_BOOT__
2347         ctx->pending_redirect=NULL;
2348 #endif
2349         ctx->child=NULL;
2350         ctx->list_head=new_pipe();
2351         ctx->pipe=ctx->list_head;
2352         ctx->w=RES_NONE;
2353         ctx->stack=NULL;
2354 #ifdef __U_BOOT__
2355         ctx->old_flag=0;
2356 #endif
2357         done_command(ctx);   /* creates the memory for working child */
2358 }
2359
2360 /* normal return is 0
2361  * if a reserved word is found, and processed, return 1
2362  * should handle if, then, elif, else, fi, for, while, until, do, done.
2363  * case, function, and select are obnoxious, save those for later.
2364  */
2365 struct reserved_combo {
2366         char *literal;
2367         int code;
2368         long flag;
2369 };
2370 /* Mostly a list of accepted follow-up reserved words.
2371  * FLAG_END means we are done with the sequence, and are ready
2372  * to turn the compound list into a command.
2373  * FLAG_START means the word must start a new compound list.
2374  */
2375 static struct reserved_combo reserved_list[] = {
2376         { "if",    RES_IF,    FLAG_THEN | FLAG_START },
2377         { "then",  RES_THEN,  FLAG_ELIF | FLAG_ELSE | FLAG_FI },
2378         { "elif",  RES_ELIF,  FLAG_THEN },
2379         { "else",  RES_ELSE,  FLAG_FI   },
2380         { "fi",    RES_FI,    FLAG_END  },
2381         { "for",   RES_FOR,   FLAG_IN   | FLAG_START },
2382         { "while", RES_WHILE, FLAG_DO   | FLAG_START },
2383         { "until", RES_UNTIL, FLAG_DO   | FLAG_START },
2384         { "in",    RES_IN,    FLAG_DO   },
2385         { "do",    RES_DO,    FLAG_DONE },
2386         { "done",  RES_DONE,  FLAG_END  }
2387 };
2388 #define NRES (sizeof(reserved_list)/sizeof(struct reserved_combo))
2389
2390 static int reserved_word(o_string *dest, struct p_context *ctx)
2391 {
2392         struct reserved_combo *r;
2393         for (r=reserved_list;
2394                 r<reserved_list+NRES; r++) {
2395                 if (strcmp(dest->data, r->literal) == 0) {
2396                         debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
2397                         if (r->flag & FLAG_START) {
2398                                 struct p_context *new = xmalloc(sizeof(struct p_context));
2399                                 debug_printf("push stack\n");
2400                                 if (ctx->w == RES_IN || ctx->w == RES_FOR) {
2401                                         syntax();
2402                                         free(new);
2403                                         ctx->w = RES_SNTX;
2404                                         b_reset(dest);
2405                                         return 1;
2406                                 }
2407                                 *new = *ctx;   /* physical copy */
2408                                 initialize_context(ctx);
2409                                 ctx->stack=new;
2410                         } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
2411                                 syntax();
2412                                 ctx->w = RES_SNTX;
2413                                 b_reset(dest);
2414                                 return 1;
2415                         }
2416                         ctx->w=r->code;
2417                         ctx->old_flag = r->flag;
2418                         if (ctx->old_flag & FLAG_END) {
2419                                 struct p_context *old;
2420                                 debug_printf("pop stack\n");
2421                                 done_pipe(ctx,PIPE_SEQ);
2422                                 old = ctx->stack;
2423                                 old->child->group = ctx->list_head;
2424 #ifndef __U_BOOT__
2425                                 old->child->subshell = 0;
2426 #endif
2427                                 *ctx = *old;   /* physical copy */
2428                                 free(old);
2429                         }
2430                         b_reset (dest);
2431                         return 1;
2432                 }
2433         }
2434         return 0;
2435 }
2436
2437 /* normal return is 0.
2438  * Syntax or xglob errors return 1. */
2439 static int done_word(o_string *dest, struct p_context *ctx)
2440 {
2441         struct child_prog *child=ctx->child;
2442 #ifndef __U_BOOT__
2443         glob_t *glob_target;
2444         int gr, flags = 0;
2445 #else
2446         char *str, *s;
2447         int argc, cnt;
2448 #endif
2449
2450         debug_printf("done_word: %s %p\n", dest->data, child);
2451         if (dest->length == 0 && !dest->nonnull) {
2452                 debug_printf("  true null, ignored\n");
2453                 return 0;
2454         }
2455 #ifndef __U_BOOT__
2456         if (ctx->pending_redirect) {
2457                 glob_target = &ctx->pending_redirect->word;
2458         } else {
2459 #endif
2460                 if (child->group) {
2461                         syntax();
2462                         return 1;  /* syntax error, groups and arglists don't mix */
2463                 }
2464                 if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
2465                         debug_printf("checking %s for reserved-ness\n",dest->data);
2466                         if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX;
2467                 }
2468 #ifndef __U_BOOT__
2469                 glob_target = &child->glob_result;
2470                 if (child->argv) flags |= GLOB_APPEND;
2471 #else
2472                 for (cnt = 1, s = dest->data; s && *s; s++) {
2473                         if (*s == '\\') s++;
2474                         cnt++;
2475                 }
2476                 str = malloc(cnt);
2477                 if (!str) return 1;
2478                 if ( child->argv == NULL) {
2479                         child->argc=0;
2480                 }
2481                 argc = ++child->argc;
2482                 child->argv = realloc(child->argv, (argc+1)*sizeof(*child->argv));
2483                 if (child->argv == NULL) {
2484                         free(str);
2485                         return 1;
2486                 }
2487                 child->argv_nonnull = realloc(child->argv_nonnull,
2488                                         (argc+1)*sizeof(*child->argv_nonnull));
2489                 if (child->argv_nonnull == NULL) {
2490                         free(str);
2491                         return 1;
2492                 }
2493                 child->argv[argc-1]=str;
2494                 child->argv_nonnull[argc-1] = dest->nonnull;
2495                 child->argv[argc]=NULL;
2496                 child->argv_nonnull[argc] = 0;
2497                 for (s = dest->data; s && *s; s++,str++) {
2498                         if (*s == '\\') s++;
2499                         *str = *s;
2500                 }
2501                 *str = '\0';
2502 #endif
2503 #ifndef __U_BOOT__
2504         }
2505         gr = xglob(dest, flags, glob_target);
2506         if (gr != 0) return 1;
2507 #endif
2508
2509         b_reset(dest);
2510 #ifndef __U_BOOT__
2511         if (ctx->pending_redirect) {
2512                 ctx->pending_redirect=NULL;
2513                 if (glob_target->gl_pathc != 1) {
2514                         error_msg("ambiguous redirect");
2515                         return 1;
2516                 }
2517         } else {
2518                 child->argv = glob_target->gl_pathv;
2519         }
2520 #endif
2521         if (ctx->w == RES_FOR) {
2522                 done_word(dest,ctx);
2523                 done_pipe(ctx,PIPE_SEQ);
2524         }
2525         return 0;
2526 }
2527
2528 /* The only possible error here is out of memory, in which case
2529  * xmalloc exits. */
2530 static int done_command(struct p_context *ctx)
2531 {
2532         /* The child is really already in the pipe structure, so
2533          * advance the pipe counter and make a new, null child.
2534          * Only real trickiness here is that the uncommitted
2535          * child structure, to which ctx->child points, is not
2536          * counted in pi->num_progs. */
2537         struct pipe *pi=ctx->pipe;
2538         struct child_prog *prog=ctx->child;
2539
2540         if (prog && prog->group == NULL
2541                  && prog->argv == NULL
2542 #ifndef __U_BOOT__
2543                  && prog->redirects == NULL) {
2544 #else
2545                                                                                 ) {
2546 #endif
2547                 debug_printf("done_command: skipping null command\n");
2548                 return 0;
2549         } else if (prog) {
2550                 pi->num_progs++;
2551                 debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
2552         } else {
2553                 debug_printf("done_command: initializing\n");
2554         }
2555         pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
2556
2557         prog = pi->progs + pi->num_progs;
2558 #ifndef __U_BOOT__
2559         prog->redirects = NULL;
2560 #endif
2561         prog->argv = NULL;
2562         prog->argv_nonnull = NULL;
2563 #ifndef __U_BOOT__
2564         prog->is_stopped = 0;
2565 #endif
2566         prog->group = NULL;
2567 #ifndef __U_BOOT__
2568         prog->glob_result.gl_pathv = NULL;
2569         prog->family = pi;
2570 #endif
2571         prog->sp = 0;
2572         ctx->child = prog;
2573         prog->type = ctx->type;
2574
2575         /* but ctx->pipe and ctx->list_head remain unchanged */
2576         return 0;
2577 }
2578
2579 static int done_pipe(struct p_context *ctx, pipe_style type)
2580 {
2581         struct pipe *new_p;
2582         done_command(ctx);  /* implicit closure of previous command */
2583         debug_printf("done_pipe, type %d\n", type);
2584         ctx->pipe->followup = type;
2585         ctx->pipe->r_mode = ctx->w;
2586         new_p=new_pipe();
2587         ctx->pipe->next = new_p;
2588         ctx->pipe = new_p;
2589         ctx->child = NULL;
2590         done_command(ctx);  /* set up new pipe to accept commands */
2591         return 0;
2592 }
2593
2594 #ifndef __U_BOOT__
2595 /* peek ahead in the in_str to find out if we have a "&n" construct,
2596  * as in "2>&1", that represents duplicating a file descriptor.
2597  * returns either -2 (syntax error), -1 (no &), or the number found.
2598  */
2599 static int redirect_dup_num(struct in_str *input)
2600 {
2601         int ch, d=0, ok=0;
2602         ch = b_peek(input);
2603         if (ch != '&') return -1;
2604
2605         b_getch(input);  /* get the & */
2606         ch=b_peek(input);
2607         if (ch == '-') {
2608                 b_getch(input);
2609                 return -3;  /* "-" represents "close me" */
2610         }
2611         while (isdigit(ch)) {
2612                 d = d*10+(ch-'0');
2613                 ok=1;
2614                 b_getch(input);
2615                 ch = b_peek(input);
2616         }
2617         if (ok) return d;
2618
2619         error_msg("ambiguous redirect");
2620         return -2;
2621 }
2622
2623 /* If a redirect is immediately preceded by a number, that number is
2624  * supposed to tell which file descriptor to redirect.  This routine
2625  * looks for such preceding numbers.  In an ideal world this routine
2626  * needs to handle all the following classes of redirects...
2627  *     echo 2>foo     # redirects fd  2 to file "foo", nothing passed to echo
2628  *     echo 49>foo    # redirects fd 49 to file "foo", nothing passed to echo
2629  *     echo -2>foo    # redirects fd  1 to file "foo",    "-2" passed to echo
2630  *     echo 49x>foo   # redirects fd  1 to file "foo",   "49x" passed to echo
2631  * A -1 output from this program means no valid number was found, so the
2632  * caller should use the appropriate default for this redirection.
2633  */
2634 static int redirect_opt_num(o_string *o)
2635 {
2636         int num;
2637
2638         if (o->length==0) return -1;
2639         for(num=0; num<o->length; num++) {
2640                 if (!isdigit(*(o->data+num))) {
2641                         return -1;
2642                 }
2643         }
2644         /* reuse num (and save an int) */
2645         num=atoi(o->data);
2646         b_reset(o);
2647         return num;
2648 }
2649
2650 FILE *generate_stream_from_list(struct pipe *head)
2651 {
2652         FILE *pf;
2653 #if 1
2654         int pid, channel[2];
2655         if (pipe(channel)<0) perror_msg_and_die("pipe");
2656         pid=fork();
2657         if (pid<0) {
2658                 perror_msg_and_die("fork");
2659         } else if (pid==0) {
2660                 close(channel[0]);
2661                 if (channel[1] != 1) {
2662                         dup2(channel[1],1);
2663                         close(channel[1]);
2664                 }
2665 #if 0
2666 #define SURROGATE "surrogate response"
2667                 write(1,SURROGATE,sizeof(SURROGATE));
2668                 _exit(run_list(head));
2669 #else
2670                 _exit(run_list_real(head));   /* leaks memory */
2671 #endif
2672         }
2673         debug_printf("forked child %d\n",pid);
2674         close(channel[1]);
2675         pf = fdopen(channel[0],"r");
2676         debug_printf("pipe on FILE *%p\n",pf);
2677 #else
2678         free_pipe_list(head,0);
2679         pf=popen("echo surrogate response","r");
2680         debug_printf("started fake pipe on FILE *%p\n",pf);
2681 #endif
2682         return pf;
2683 }
2684
2685 /* this version hacked for testing purposes */
2686 /* return code is exit status of the process that is run. */
2687 static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
2688 {
2689         int retcode;
2690         o_string result=NULL_O_STRING;
2691         struct p_context inner;
2692         FILE *p;
2693         struct in_str pipe_str;
2694         initialize_context(&inner);
2695
2696         /* recursion to generate command */
2697         retcode = parse_stream(&result, &inner, input, subst_end);
2698         if (retcode != 0) return retcode;  /* syntax error or EOF */
2699         done_word(&result, &inner);
2700         done_pipe(&inner, PIPE_SEQ);
2701         b_free(&result);
2702
2703         p=generate_stream_from_list(inner.list_head);
2704         if (p==NULL) return 1;
2705         mark_open(fileno(p));
2706         setup_file_in_str(&pipe_str, p);
2707
2708         /* now send results of command back into original context */
2709         retcode = parse_stream(dest, ctx, &pipe_str, '\0');
2710         /* XXX In case of a syntax error, should we try to kill the child?
2711          * That would be tough to do right, so just read until EOF. */
2712         if (retcode == 1) {
2713                 while (b_getch(&pipe_str)!=EOF) { /* discard */ };
2714         }
2715
2716         debug_printf("done reading from pipe, pclose()ing\n");
2717         /* This is the step that wait()s for the child.  Should be pretty
2718          * safe, since we just read an EOF from its stdout.  We could try
2719          * to better, by using wait(), and keeping track of background jobs
2720          * at the same time.  That would be a lot of work, and contrary
2721          * to the KISS philosophy of this program. */
2722         mark_closed(fileno(p));
2723         retcode=pclose(p);
2724         free_pipe_list(inner.list_head,0);
2725         debug_printf("pclosed, retcode=%d\n",retcode);
2726         /* XXX this process fails to trim a single trailing newline */
2727         return retcode;
2728 }
2729
2730 static int parse_group(o_string *dest, struct p_context *ctx,
2731         struct in_str *input, int ch)
2732 {
2733         int rcode, endch=0;
2734         struct p_context sub;
2735         struct child_prog *child = ctx->child;
2736         if (child->argv) {
2737                 syntax();
2738                 return 1;  /* syntax error, groups and arglists don't mix */
2739         }
2740         initialize_context(&sub);
2741         switch(ch) {
2742                 case '(': endch=')'; child->subshell=1; break;
2743                 case '{': endch='}'; break;
2744                 default: syntax();   /* really logic error */
2745         }
2746         rcode=parse_stream(dest,&sub,input,endch);
2747         done_word(dest,&sub); /* finish off the final word in the subcontext */
2748         done_pipe(&sub, PIPE_SEQ);  /* and the final command there, too */
2749         child->group = sub.list_head;
2750         return rcode;
2751         /* child remains "open", available for possible redirects */
2752 }
2753 #endif
2754
2755 /* basically useful version until someone wants to get fancier,
2756  * see the bash man page under "Parameter Expansion" */
2757 static char *lookup_param(char *src)
2758 {
2759         char *p;
2760         char *sep;
2761         char *default_val = NULL;
2762         int assign = 0;
2763         int expand_empty = 0;
2764
2765         if (!src)
2766                 return NULL;
2767
2768         sep = strchr(src, ':');
2769
2770         if (sep) {
2771                 *sep = '\0';
2772                 if (*(sep + 1) == '-')
2773                         default_val = sep+2;
2774                 if (*(sep + 1) == '=') {
2775                         default_val = sep+2;
2776                         assign = 1;
2777                 }
2778                 if (*(sep + 1) == '+') {
2779                         default_val = sep+2;
2780                         expand_empty = 1;
2781                 }
2782         }
2783
2784         p = env_get(src);
2785         if (!p)
2786                 p = get_local_var(src);
2787
2788         if (!p || strlen(p) == 0) {
2789                 p = default_val;
2790                 if (assign) {
2791                         char *var = malloc(strlen(src)+strlen(default_val)+2);
2792                         if (var) {
2793                                 sprintf(var, "%s=%s", src, default_val);
2794                                 set_local_var(var, 0);
2795                         }
2796                         free(var);
2797                 }
2798         } else if (expand_empty) {
2799                 p += strlen(p);
2800         }
2801
2802         if (sep)
2803                 *sep = ':';
2804
2805         return p;
2806 }
2807
2808 #ifdef __U_BOOT__
2809 static char *get_dollar_var(char ch)
2810 {
2811         static char buf[40];
2812
2813         buf[0] = '\0';
2814         switch (ch) {
2815                 case '?':
2816                         sprintf(buf, "%u", (unsigned int)last_return_code);
2817                         break;
2818                 default:
2819                         return NULL;
2820         }
2821         return buf;
2822 }
2823 #endif
2824
2825 /* return code: 0 for OK, 1 for syntax error */
2826 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
2827 {
2828 #ifndef __U_BOOT__
2829         int i, advance=0;
2830 #else
2831         int advance=0;
2832 #endif
2833 #ifndef __U_BOOT__
2834         char sep[]=" ";
2835 #endif
2836         int ch = input->peek(input);  /* first character after the $ */
2837         debug_printf("handle_dollar: ch=%c\n",ch);
2838         if (isalpha(ch)) {
2839                 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2840                 ctx->child->sp++;
2841                 while(ch=b_peek(input),isalnum(ch) || ch=='_') {
2842                         b_getch(input);
2843                         b_addchr(dest,ch);
2844                 }
2845                 b_addchr(dest, SPECIAL_VAR_SYMBOL);
2846 #ifndef __U_BOOT__
2847         } else if (isdigit(ch)) {
2848                 i = ch-'0';  /* XXX is $0 special? */
2849                 if (i<global_argc) {
2850                         parse_string(dest, ctx, global_argv[i]); /* recursion */
2851                 }
2852                 advance = 1;
2853 #endif
2854         } else switch (ch) {
2855 #ifndef __U_BOOT__
2856                 case '$':
2857                         b_adduint(dest,getpid());
2858                         advance = 1;
2859                         break;
2860                 case '!':
2861                         if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
2862                         advance = 1;
2863                         break;
2864 #endif
2865                 case '?':
2866 #ifndef __U_BOOT__
2867                         b_adduint(dest,last_return_code);
2868 #else
2869                         ctx->child->sp++;
2870                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2871                         b_addchr(dest, '$');
2872                         b_addchr(dest, '?');
2873                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2874 #endif
2875                         advance = 1;
2876                         break;
2877 #ifndef __U_BOOT__
2878                 case '#':
2879                         b_adduint(dest,global_argc ? global_argc-1 : 0);
2880                         advance = 1;
2881                         break;
2882 #endif
2883                 case '{':
2884                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2885                         ctx->child->sp++;
2886                         b_getch(input);
2887                         /* XXX maybe someone will try to escape the '}' */
2888                         while(ch=b_getch(input),ch!=EOF && ch!='}') {
2889                                 b_addchr(dest,ch);
2890                         }
2891                         if (ch != '}') {
2892                                 syntax();
2893                                 return 1;
2894                         }
2895                         b_addchr(dest, SPECIAL_VAR_SYMBOL);
2896                         break;
2897 #ifndef __U_BOOT__
2898                 case '(':
2899                         b_getch(input);
2900                         process_command_subs(dest, ctx, input, ')');
2901                         break;
2902                 case '*':
2903                         sep[0]=ifs[0];
2904                         for (i=1; i<global_argc; i++) {
2905                                 parse_string(dest, ctx, global_argv[i]);
2906                                 if (i+1 < global_argc) parse_string(dest, ctx, sep);
2907                         }
2908                         break;
2909                 case '@':
2910                 case '-':
2911                 case '_':
2912                         /* still unhandled, but should be eventually */
2913                         error_msg("unhandled syntax: $%c",ch);
2914                         return 1;
2915                         break;
2916 #endif
2917                 default:
2918                         b_addqchr(dest,'$',dest->quote);
2919         }
2920         /* Eat the character if the flag was set.  If the compiler
2921          * is smart enough, we could substitute "b_getch(input);"
2922          * for all the "advance = 1;" above, and also end up with
2923          * a nice size-optimized program.  Hah!  That'll be the day.
2924          */
2925         if (advance) b_getch(input);
2926         return 0;
2927 }
2928
2929 #ifndef __U_BOOT__
2930 int parse_string(o_string *dest, struct p_context *ctx, const char *src)
2931 {
2932         struct in_str foo;
2933         setup_string_in_str(&foo, src);
2934         return parse_stream(dest, ctx, &foo, '\0');
2935 }
2936 #endif
2937
2938 /* return code is 0 for normal exit, 1 for syntax error */
2939 static int parse_stream(o_string *dest, struct p_context *ctx,
2940                         struct in_str *input, int end_trigger)
2941 {
2942         unsigned int ch, m;
2943 #ifndef __U_BOOT__
2944         int redir_fd;
2945         redir_type redir_style;
2946 #endif
2947         int next;
2948
2949         /* Only double-quote state is handled in the state variable dest->quote.
2950          * A single-quote triggers a bypass of the main loop until its mate is
2951          * found.  When recursing, quote state is passed in via dest->quote. */
2952
2953         debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
2954         while ((ch=b_getch(input))!=EOF) {
2955                 m = map[ch];
2956 #ifdef __U_BOOT__
2957                 if (input->__promptme == 0) return 1;
2958 #endif
2959                 next = (ch == '\n') ? 0 : b_peek(input);
2960
2961                 debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d - %c\n",
2962                         ch >= ' ' ? ch : '.', ch, m,
2963                         dest->quote, ctx->stack == NULL ? '*' : '.');
2964
2965                 if (m==0 || ((m==1 || m==2) && dest->quote)) {
2966                         b_addqchr(dest, ch, dest->quote);
2967                 } else {
2968                         if (m==2) {  /* unquoted IFS */
2969                                 if (done_word(dest, ctx)) {
2970                                         return 1;
2971                                 }
2972                                 /* If we aren't performing a substitution, treat a newline as a
2973                                  * command separator.  */
2974                                 if (end_trigger != '\0' && ch=='\n')
2975                                         done_pipe(ctx,PIPE_SEQ);
2976                         }
2977                         if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) {
2978                                 debug_printf("leaving parse_stream (triggered)\n");
2979                                 return 0;
2980                         }
2981 #if 0
2982                         if (ch=='\n') {
2983                                 /* Yahoo!  Time to run with it! */
2984                                 done_pipe(ctx,PIPE_SEQ);
2985                                 run_list(ctx->list_head);
2986                                 initialize_context(ctx);
2987                         }
2988 #endif
2989                         if (m!=2) switch (ch) {
2990                 case '#':
2991                         if (dest->length == 0 && !dest->quote) {
2992                                 while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
2993                         } else {
2994                                 b_addqchr(dest, ch, dest->quote);
2995                         }
2996                         break;
2997                 case '\\':
2998                         if (next == EOF) {
2999                                 syntax();
3000                                 return 1;
3001                         }
3002                         b_addqchr(dest, '\\', dest->quote);
3003                         b_addqchr(dest, b_getch(input), dest->quote);
3004                         break;
3005                 case '$':
3006                         if (handle_dollar(dest, ctx, input)!=0) return 1;
3007                         break;
3008                 case '\'':
3009                         dest->nonnull = 1;
3010                         while(ch=b_getch(input),ch!=EOF && ch!='\'') {
3011 #ifdef __U_BOOT__
3012                                 if(input->__promptme == 0) return 1;
3013 #endif
3014                                 b_addchr(dest,ch);
3015                         }
3016                         if (ch==EOF) {
3017                                 syntax();
3018                                 return 1;
3019                         }
3020                         break;
3021                 case '"':
3022                         dest->nonnull = 1;
3023                         dest->quote = !dest->quote;
3024                         break;
3025 #ifndef __U_BOOT__
3026                 case '`':
3027                         process_command_subs(dest, ctx, input, '`');
3028                         break;
3029                 case '>':
3030                         redir_fd = redirect_opt_num(dest);
3031                         done_word(dest, ctx);
3032                         redir_style=REDIRECT_OVERWRITE;
3033                         if (next == '>') {
3034                                 redir_style=REDIRECT_APPEND;
3035                                 b_getch(input);
3036                         } else if (next == '(') {
3037                                 syntax();   /* until we support >(list) Process Substitution */
3038                                 return 1;
3039                         }
3040                         setup_redirect(ctx, redir_fd, redir_style, input);
3041                         break;
3042                 case '<':
3043                         redir_fd = redirect_opt_num(dest);
3044                         done_word(dest, ctx);
3045                         redir_style=REDIRECT_INPUT;
3046                         if (next == '<') {
3047                                 redir_style=REDIRECT_HEREIS;
3048                                 b_getch(input);
3049                         } else if (next == '>') {
3050                                 redir_style=REDIRECT_IO;
3051                                 b_getch(input);
3052                         } else if (next == '(') {
3053                                 syntax();   /* until we support <(list) Process Substitution */
3054                                 return 1;
3055                         }
3056                         setup_redirect(ctx, redir_fd, redir_style, input);
3057                         break;
3058 #endif
3059                 case ';':
3060                         done_word(dest, ctx);
3061                         done_pipe(ctx,PIPE_SEQ);
3062                         break;
3063                 case '&':
3064                         done_word(dest, ctx);
3065                         if (next=='&') {
3066                                 b_getch(input);
3067                                 done_pipe(ctx,PIPE_AND);
3068                         } else {
3069 #ifndef __U_BOOT__
3070                                 done_pipe(ctx,PIPE_BG);
3071 #else
3072                                 syntax_err();
3073                                 return 1;
3074 #endif
3075                         }
3076                         break;
3077                 case '|':
3078                         done_word(dest, ctx);
3079                         if (next=='|') {
3080                                 b_getch(input);
3081                                 done_pipe(ctx,PIPE_OR);
3082                         } else {
3083                                 /* we could pick up a file descriptor choice here
3084                                  * with redirect_opt_num(), but bash doesn't do it.
3085                                  * "echo foo 2| cat" yields "foo 2". */
3086 #ifndef __U_BOOT__
3087                                 done_command(ctx);
3088 #else
3089                                 syntax_err();
3090                                 return 1;
3091 #endif
3092                         }
3093                         break;
3094 #ifndef __U_BOOT__
3095                 case '(':
3096                 case '{':
3097                         if (parse_group(dest, ctx, input, ch)!=0) return 1;
3098                         break;
3099                 case ')':
3100                 case '}':
3101                         syntax();   /* Proper use of this character caught by end_trigger */
3102                         return 1;
3103                         break;
3104 #endif
3105                 case SUBSTED_VAR_SYMBOL:
3106                         dest->nonnull = 1;
3107                         while (ch = b_getch(input), ch != EOF &&
3108                             ch != SUBSTED_VAR_SYMBOL) {
3109                                 debug_printf("subst, pass=%d\n", ch);
3110                                 if (input->__promptme == 0)
3111                                         return 1;
3112                                 b_addchr(dest, ch);
3113                         }
3114                         debug_printf("subst, term=%d\n", ch);
3115                         if (ch == EOF) {
3116                                 syntax();
3117                                 return 1;
3118                         }
3119                         break;
3120                 default:
3121                         syntax();   /* this is really an internal logic error */
3122                         return 1;
3123                         }
3124                 }
3125         }
3126         /* complain if quote?  No, maybe we just finished a command substitution
3127          * that was quoted.  Example:
3128          * $ echo "`cat foo` plus more"
3129          * and we just got the EOF generated by the subshell that ran "cat foo"
3130          * The only real complaint is if we got an EOF when end_trigger != '\0',
3131          * that is, we were really supposed to get end_trigger, and never got
3132          * one before the EOF.  Can't use the standard "syntax error" return code,
3133          * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
3134         debug_printf("leaving parse_stream (EOF)\n");
3135         if (end_trigger != '\0') return -1;
3136         return 0;
3137 }
3138
3139 static void mapset(const unsigned char *set, int code)
3140 {
3141         const unsigned char *s;
3142         for (s=set; *s; s++) map[*s] = code;
3143 }
3144
3145 static void update_ifs_map(void)
3146 {
3147         /* char *ifs and char map[256] are both globals. */
3148         ifs = (uchar *)env_get("IFS");
3149         if (ifs == NULL) ifs=(uchar *)" \t\n";
3150         /* Precompute a list of 'flow through' behavior so it can be treated
3151          * quickly up front.  Computation is necessary because of IFS.
3152          * Special case handling of IFS == " \t\n" is not implemented.
3153          * The map[] array only really needs two bits each, and on most machines
3154          * that would be faster because of the reduced L1 cache footprint.
3155          */
3156         memset(map,0,sizeof(map)); /* most characters flow through always */
3157 #ifndef __U_BOOT__
3158         mapset((uchar *)"\\$'\"`", 3);      /* never flow through */
3159         mapset((uchar *)"<>;&|(){}#", 1);   /* flow through if quoted */
3160 #else
3161         {
3162                 uchar subst[2] = {SUBSTED_VAR_SYMBOL, 0};
3163                 mapset(subst, 3);       /* never flow through */
3164         }
3165         mapset((uchar *)"\\$'\"", 3);       /* never flow through */
3166         mapset((uchar *)";&|#", 1);         /* flow through if quoted */
3167 #endif
3168         mapset(ifs, 2);            /* also flow through if quoted */
3169 }
3170
3171 /* most recursion does not come through here, the exeception is
3172  * from builtin_source() */
3173 static int parse_stream_outer(struct in_str *inp, int flag)
3174 {
3175
3176         struct p_context ctx;
3177         o_string temp=NULL_O_STRING;
3178         int rcode;
3179 #ifdef __U_BOOT__
3180         int code = 1;
3181 #endif
3182         do {
3183                 ctx.type = flag;
3184                 initialize_context(&ctx);
3185                 update_ifs_map();
3186                 if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset((uchar *)";$&|", 0);
3187                 inp->promptmode=1;
3188                 rcode = parse_stream(&temp, &ctx, inp,
3189                                      flag & FLAG_CONT_ON_NEWLINE ? -1 : '\n');
3190 #ifdef __U_BOOT__
3191                 if (rcode == 1) flag_repeat = 0;
3192 #endif
3193                 if (rcode != 1 && ctx.old_flag != 0) {
3194                         syntax();
3195 #ifdef __U_BOOT__
3196                         flag_repeat = 0;
3197 #endif
3198                 }
3199                 if (rcode != 1 && ctx.old_flag == 0) {
3200                         done_word(&temp, &ctx);
3201                         done_pipe(&ctx,PIPE_SEQ);
3202 #ifndef __U_BOOT__
3203                         run_list(ctx.list_head);
3204 #else
3205                         code = run_list(ctx.list_head);
3206                         if (code == -2) {       /* exit */
3207                                 b_free(&temp);
3208                                 code = 0;
3209                                 /* XXX hackish way to not allow exit from main loop */
3210                                 if (inp->peek == file_peek) {
3211                                         printf("exit not allowed from main input shell.\n");
3212                                         continue;
3213                                 }
3214                                 /*
3215                                  * DANGER
3216                                  * Return code -2 is special in this context,
3217                                  * it indicates exit from inner pipe instead
3218                                  * of return code itself, the return code is
3219                                  * stored in 'last_return_code' variable!
3220                                  * DANGER
3221                                  */
3222                                 return -2;
3223                         }
3224                         if (code == -1)
3225                             flag_repeat = 0;
3226 #endif
3227                 } else {
3228                         if (ctx.old_flag != 0) {
3229                                 free(ctx.stack);
3230                                 b_reset(&temp);
3231                         }
3232 #ifdef __U_BOOT__
3233                         if (inp->__promptme == 0) printf("<INTERRUPT>\n");
3234                         inp->__promptme = 1;
3235 #endif
3236                         temp.nonnull = 0;
3237                         temp.quote = 0;
3238                         inp->p = NULL;
3239                         free_pipe_list(ctx.list_head,0);
3240                 }
3241                 b_free(&temp);
3242         /* loop on syntax errors, return on EOF */
3243         } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP) &&
3244                 (inp->peek != static_peek || b_peek(inp)));
3245 #ifndef __U_BOOT__
3246         return 0;
3247 #else
3248         return (code != 0) ? 1 : 0;
3249 #endif /* __U_BOOT__ */
3250 }
3251
3252 #ifndef __U_BOOT__
3253 static int parse_string_outer(const char *s, int flag)
3254 #else
3255 int parse_string_outer(const char *s, int flag)
3256 #endif  /* __U_BOOT__ */
3257 {
3258         struct in_str input;
3259         int rcode;
3260 #ifdef __U_BOOT__
3261         char *p = NULL;
3262         if (!s)
3263                 return 1;
3264         if (!*s)
3265                 return 0;
3266         if (!(p = strchr(s, '\n')) || *++p) {
3267                 p = xmalloc(strlen(s) + 2);
3268                 strcpy(p, s);
3269                 strcat(p, "\n");
3270                 setup_string_in_str(&input, p);
3271                 rcode = parse_stream_outer(&input, flag);
3272                 free(p);
3273                 return rcode == -2 ? last_return_code : rcode;
3274         } else {
3275 #endif
3276         setup_string_in_str(&input, s);
3277         rcode = parse_stream_outer(&input, flag);
3278         return rcode == -2 ? last_return_code : rcode;
3279 #ifdef __U_BOOT__
3280         }
3281 #endif
3282 }
3283
3284 #ifndef __U_BOOT__
3285 static int parse_file_outer(FILE *f)
3286 #else
3287 int parse_file_outer(void)
3288 #endif
3289 {
3290         int rcode;
3291         struct in_str input;
3292 #ifndef __U_BOOT__
3293         setup_file_in_str(&input, f);
3294 #else
3295         setup_file_in_str(&input);
3296 #endif
3297         rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
3298         return rcode == -2 ? last_return_code : rcode;
3299 }
3300
3301 #ifdef __U_BOOT__
3302 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3303 static void u_boot_hush_reloc(void)
3304 {
3305         unsigned long addr;
3306         struct reserved_combo *r;
3307
3308         for (r=reserved_list; r<reserved_list+NRES; r++) {
3309                 addr = (ulong) (r->literal) + gd->reloc_off;
3310                 r->literal = (char *)addr;
3311         }
3312 }
3313 #endif
3314
3315 int u_boot_hush_start(void)
3316 {
3317         if (top_vars == NULL) {
3318                 top_vars = malloc(sizeof(struct variables));
3319                 top_vars->name = "HUSH_VERSION";
3320                 top_vars->value = "0.01";
3321                 top_vars->next = NULL;
3322                 top_vars->flg_export = 0;
3323                 top_vars->flg_read_only = 1;
3324 #ifdef CONFIG_NEEDS_MANUAL_RELOC
3325                 u_boot_hush_reloc();
3326 #endif
3327         }
3328         return 0;
3329 }
3330
3331 static void *xmalloc(size_t size)
3332 {
3333         void *p = NULL;
3334
3335         if (!(p = malloc(size))) {
3336             printf("ERROR : xmalloc failed\n");
3337             for(;;);
3338         }
3339         return p;
3340 }
3341
3342 static void *xrealloc(void *ptr, size_t size)
3343 {
3344         void *p = NULL;
3345
3346         if (!(p = realloc(ptr, size))) {
3347             printf("ERROR : xrealloc failed\n");
3348             for(;;);
3349         }
3350         return p;
3351 }
3352 #endif /* __U_BOOT__ */
3353
3354 #ifndef __U_BOOT__
3355 /* Make sure we have a controlling tty.  If we get started under a job
3356  * aware app (like bash for example), make sure we are now in charge so
3357  * we don't fight over who gets the foreground */
3358 static void setup_job_control(void)
3359 {
3360         static pid_t shell_pgrp;
3361         /* Loop until we are in the foreground.  */
3362         while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
3363                 kill (- shell_pgrp, SIGTTIN);
3364
3365         /* Ignore interactive and job-control signals.  */
3366         signal(SIGINT, SIG_IGN);
3367         signal(SIGQUIT, SIG_IGN);
3368         signal(SIGTERM, SIG_IGN);
3369         signal(SIGTSTP, SIG_IGN);
3370         signal(SIGTTIN, SIG_IGN);
3371         signal(SIGTTOU, SIG_IGN);
3372         signal(SIGCHLD, SIG_IGN);
3373
3374         /* Put ourselves in our own process group.  */
3375         setsid();
3376         shell_pgrp = getpid ();
3377         setpgid (shell_pgrp, shell_pgrp);
3378
3379         /* Grab control of the terminal.  */
3380         tcsetpgrp(shell_terminal, shell_pgrp);
3381 }
3382
3383 int hush_main(int argc, char * const *argv)
3384 {
3385         int opt;
3386         FILE *input;
3387         char **e = environ;
3388
3389         /* XXX what should these be while sourcing /etc/profile? */
3390         global_argc = argc;
3391         global_argv = argv;
3392
3393         /* (re?) initialize globals.  Sometimes hush_main() ends up calling
3394          * hush_main(), therefore we cannot rely on the BSS to zero out this
3395          * stuff.  Reset these to 0 every time. */
3396         ifs = NULL;
3397         /* map[] is taken care of with call to update_ifs_map() */
3398         fake_mode = 0;
3399         interactive = 0;
3400         close_me_head = NULL;
3401         last_bg_pid = 0;
3402         job_list = NULL;
3403         last_jobid = 0;
3404
3405         /* Initialize some more globals to non-zero values */
3406         set_cwd();
3407 #ifdef CONFIG_FEATURE_COMMAND_EDITING
3408         cmdedit_set_initial_prompt();
3409 #else
3410         PS1 = NULL;
3411 #endif
3412         PS2 = "> ";
3413
3414         /* initialize our shell local variables with the values
3415          * currently living in the environment */
3416         if (e) {
3417                 for (; *e; e++)
3418                         set_local_var(*e, 2);   /* without call putenv() */
3419         }
3420
3421         last_return_code=EXIT_SUCCESS;
3422
3423
3424         if (argv[0] && argv[0][0] == '-') {
3425                 debug_printf("\nsourcing /etc/profile\n");
3426                 if ((input = fopen("/etc/profile", "r")) != NULL) {
3427                         mark_open(fileno(input));
3428                         parse_file_outer(input);
3429                         mark_closed(fileno(input));
3430                         fclose(input);
3431                 }
3432         }
3433         input=stdin;
3434
3435         while ((opt = getopt(argc, argv, "c:xif")) > 0) {
3436                 switch (opt) {
3437                         case 'c':
3438                                 {
3439                                         global_argv = argv+optind;
3440                                         global_argc = argc-optind;
3441                                         opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
3442                                         goto final_return;
3443                                 }
3444                                 break;
3445                         case 'i':
3446                                 interactive++;
3447                                 break;
3448                         case 'f':
3449                                 fake_mode++;
3450                                 break;
3451                         default:
3452 #ifndef BB_VER
3453                                 fprintf(stderr, "Usage: sh [FILE]...\n"
3454                                                 "   or: sh -c command [args]...\n\n");
3455                                 exit(EXIT_FAILURE);
3456 #else
3457                                 show_usage();
3458 #endif
3459                 }
3460         }
3461         /* A shell is interactive if the `-i' flag was given, or if all of
3462          * the following conditions are met:
3463          *        no -c command
3464          *    no arguments remaining or the -s flag given
3465          *    standard input is a terminal
3466          *    standard output is a terminal
3467          *    Refer to Posix.2, the description of the `sh' utility. */
3468         if (argv[optind]==NULL && input==stdin &&
3469                         isatty(fileno(stdin)) && isatty(fileno(stdout))) {
3470                 interactive++;
3471         }
3472
3473         debug_printf("\ninteractive=%d\n", interactive);
3474         if (interactive) {
3475                 /* Looks like they want an interactive shell */
3476 #ifndef CONFIG_FEATURE_SH_EXTRA_QUIET
3477                 printf( "\n\n" BB_BANNER " hush - the humble shell v0.01 (testing)\n");
3478                 printf( "Enter 'help' for a list of built-in commands.\n\n");
3479 #endif
3480                 setup_job_control();
3481         }
3482
3483         if (argv[optind]==NULL) {
3484                 opt=parse_file_outer(stdin);
3485                 goto final_return;
3486         }
3487
3488         debug_printf("\nrunning script '%s'\n", argv[optind]);
3489         global_argv = argv+optind;
3490         global_argc = argc-optind;
3491         input = xfopen(argv[optind], "r");
3492         opt = parse_file_outer(input);
3493
3494 #ifdef CONFIG_FEATURE_CLEAN_UP
3495         fclose(input);
3496         if (cwd && cwd != unknown)
3497                 free((char*)cwd);
3498         {
3499                 struct variables *cur, *tmp;
3500                 for(cur = top_vars; cur; cur = tmp) {
3501                         tmp = cur->next;
3502                         if (!cur->flg_read_only) {
3503                                 free(cur->name);
3504                                 free(cur->value);
3505                                 free(cur);
3506                         }
3507                 }
3508         }
3509 #endif
3510
3511 final_return:
3512         return(opt?opt:last_return_code);
3513 }
3514 #endif
3515
3516 static char *insert_var_value(char *inp)
3517 {
3518         return insert_var_value_sub(inp, 0);
3519 }
3520
3521 static char *insert_var_value_sub(char *inp, int tag_subst)
3522 {
3523         int res_str_len = 0;
3524         int len;
3525         int done = 0;
3526         char *p, *p1, *res_str = NULL;
3527
3528         while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
3529                 /* check the beginning of the string for normal characters */
3530                 if (p != inp) {
3531                         /* copy any characters to the result string */
3532                         len = p - inp;
3533                         res_str = xrealloc(res_str, (res_str_len + len));
3534                         strncpy((res_str + res_str_len), inp, len);
3535                         res_str_len += len;
3536                 }
3537                 inp = ++p;
3538                 /* find the ending marker */
3539                 p = strchr(inp, SPECIAL_VAR_SYMBOL);
3540                 *p = '\0';
3541                 /* look up the value to substitute */
3542                 if ((p1 = lookup_param(inp))) {
3543                         if (tag_subst)
3544                                 len = res_str_len + strlen(p1) + 2;
3545                         else
3546                                 len = res_str_len + strlen(p1);
3547                         res_str = xrealloc(res_str, (1 + len));
3548                         if (tag_subst) {
3549                                 /*
3550                                  * copy the variable value to the result
3551                                  * string
3552                                  */
3553                                 strcpy((res_str + res_str_len + 1), p1);
3554
3555                                 /*
3556                                  * mark the replaced text to be accepted as
3557                                  * is
3558                                  */
3559                                 res_str[res_str_len] = SUBSTED_VAR_SYMBOL;
3560                                 res_str[res_str_len + 1 + strlen(p1)] =
3561                                         SUBSTED_VAR_SYMBOL;
3562                         } else
3563                                 /*
3564                                  * copy the variable value to the result
3565                                  * string
3566                                  */
3567                                 strcpy((res_str + res_str_len), p1);
3568
3569                         res_str_len = len;
3570                 }
3571                 *p = SPECIAL_VAR_SYMBOL;
3572                 inp = ++p;
3573                 done = 1;
3574         }
3575         if (done) {
3576                 res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
3577                 strcpy((res_str + res_str_len), inp);
3578                 while ((p = strchr(res_str, '\n'))) {
3579                         *p = ' ';
3580                 }
3581         }
3582         return (res_str == NULL) ? inp : res_str;
3583 }
3584
3585 static char **make_list_in(char **inp, char *name)
3586 {
3587         int len, i;
3588         int name_len = strlen(name);
3589         int n = 0;
3590         char **list;
3591         char *p1, *p2, *p3;
3592
3593         /* create list of variable values */
3594         list = xmalloc(sizeof(*list));
3595         for (i = 0; inp[i]; i++) {
3596                 p3 = insert_var_value(inp[i]);
3597                 p1 = p3;
3598                 while (*p1) {
3599                         if (*p1 == ' ') {
3600                                 p1++;
3601                                 continue;
3602                         }
3603                         if ((p2 = strchr(p1, ' '))) {
3604                                 len = p2 - p1;
3605                         } else {
3606                                 len = strlen(p1);
3607                                 p2 = p1 + len;
3608                         }
3609                         /* we use n + 2 in realloc for list,because we add
3610                          * new element and then we will add NULL element */
3611                         list = xrealloc(list, sizeof(*list) * (n + 2));
3612                         list[n] = xmalloc(2 + name_len + len);
3613                         strcpy(list[n], name);
3614                         strcat(list[n], "=");
3615                         strncat(list[n], p1, len);
3616                         list[n++][name_len + len + 1] = '\0';
3617                         p1 = p2;
3618                 }
3619                 if (p3 != inp[i]) free(p3);
3620         }
3621         list[n] = NULL;
3622         return list;
3623 }
3624
3625 /*
3626  * Make new string for parser
3627  * inp     - array of argument strings to flatten
3628  * nonnull - indicates argument was quoted when originally parsed
3629  */
3630 static char *make_string(char **inp, int *nonnull)
3631 {
3632         char *p;
3633         char *str = NULL;
3634         int n;
3635         int len = 2;
3636         char *noeval_str;
3637         int noeval = 0;
3638
3639         noeval_str = get_local_var("HUSH_NO_EVAL");
3640         if (noeval_str != NULL && *noeval_str != '0' && *noeval_str != '\0')
3641                 noeval = 1;
3642         for (n = 0; inp[n]; n++) {
3643                 p = insert_var_value_sub(inp[n], noeval);
3644                 str = xrealloc(str, (len + strlen(p) + (2 * nonnull[n])));
3645                 if (n) {
3646                         strcat(str, " ");
3647                 } else {
3648                         *str = '\0';
3649                 }
3650                 if (nonnull[n])
3651                         strcat(str, "'");
3652                 strcat(str, p);
3653                 if (nonnull[n])
3654                         strcat(str, "'");
3655                 len = strlen(str) + 3;
3656                 if (p != inp[n]) free(p);
3657         }
3658         len = strlen(str);
3659         *(str + len) = '\n';
3660         *(str + len + 1) = '\0';
3661         return str;
3662 }
3663
3664 #ifdef __U_BOOT__
3665 static int do_showvar(struct cmd_tbl *cmdtp, int flag, int argc,
3666                       char *const argv[])
3667 {
3668         int i, k;
3669         int rcode = 0;
3670         struct variables *cur;
3671
3672         if (argc == 1) {                /* Print all env variables      */
3673                 for (cur = top_vars; cur; cur = cur->next) {
3674                         printf ("%s=%s\n", cur->name, cur->value);
3675                         if (ctrlc ()) {
3676                                 puts ("\n ** Abort\n");
3677                                 return 1;
3678                         }
3679                 }
3680                 return 0;
3681         }
3682         for (i = 1; i < argc; ++i) {    /* print single env variables   */
3683                 char *name = argv[i];
3684
3685                 k = -1;
3686                 for (cur = top_vars; cur; cur = cur->next) {
3687                         if(strcmp (cur->name, name) == 0) {
3688                                 k = 0;
3689                                 printf ("%s=%s\n", cur->name, cur->value);
3690                         }
3691                         if (ctrlc ()) {
3692                                 puts ("\n ** Abort\n");
3693                                 return 1;
3694                         }
3695                 }
3696                 if (k < 0) {
3697                         printf ("## Error: \"%s\" not defined\n", name);
3698                         rcode ++;
3699                 }
3700         }
3701         return rcode;
3702 }
3703
3704 U_BOOT_CMD(
3705         showvar, CONFIG_SYS_MAXARGS, 1, do_showvar,
3706         "print local hushshell variables",
3707         "\n    - print values of all hushshell variables\n"
3708         "showvar name ...\n"
3709         "    - print value of hushshell variable 'name'"
3710 );
3711
3712 #endif
3713 /****************************************************************************/