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