common/cli_hush.c

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