Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 1 | /* vi: set sw=4 ts=4: */ |
| 2 | /* |
| 3 | * sh.c -- a prototype Bourne shell grammar parser |
| 4 | * Intended to follow the original Thompson and Ritchie |
| 5 | * "small and simple is beautiful" philosophy, which |
| 6 | * incidentally is a good match to today's BusyBox. |
| 7 | * |
| 8 | * Copyright (C) 2000,2001 Larry Doolittle <larry@doolittle.boa.org> |
| 9 | * |
| 10 | * Credits: |
| 11 | * The parser routines proper are all original material, first |
| 12 | * written Dec 2000 and Jan 2001 by Larry Doolittle. |
| 13 | * The execution engine, the builtins, and much of the underlying |
| 14 | * support has been adapted from busybox-0.49pre's lash, |
| 15 | * which is Copyright (C) 2000 by Lineo, Inc., and |
| 16 | * written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>. |
| 17 | * That, in turn, is based in part on ladsh.c, by Michael K. Johnson and |
| 18 | * Erik W. Troan, which they placed in the public domain. I don't know |
| 19 | * how much of the Johnson/Troan code has survived the repeated rewrites. |
| 20 | * Other credits: |
| 21 | * simple_itoa() was lifted from boa-0.93.15 |
| 22 | * b_addchr() derived from similar w_addchar function in glibc-2.2 |
| 23 | * setup_redirect(), redirect_opt_num(), and big chunks of main() |
| 24 | * and many builtins derived from contributions by Erik Andersen |
| 25 | * miscellaneous bugfixes from Matt Kraai |
| 26 | * |
| 27 | * There are two big (and related) architecture differences between |
| 28 | * this parser and the lash parser. One is that this version is |
| 29 | * actually designed from the ground up to understand nearly all |
| 30 | * of the Bourne grammar. The second, consequential change is that |
| 31 | * the parser and input reader have been turned inside out. Now, |
| 32 | * the parser is in control, and asks for input as needed. The old |
| 33 | * way had the input reader in control, and it asked for parsing to |
| 34 | * take place as needed. The new way makes it much easier to properly |
| 35 | * handle the recursion implicit in the various substitutions, especially |
| 36 | * across continuation lines. |
| 37 | * |
| 38 | * Bash grammar not implemented: (how many of these were in original sh?) |
| 39 | * $@ (those sure look like weird quoting rules) |
| 40 | * $_ |
| 41 | * ! negation operator for pipes |
| 42 | * &> and >& redirection of stdout+stderr |
| 43 | * Brace Expansion |
| 44 | * Tilde Expansion |
| 45 | * fancy forms of Parameter Expansion |
| 46 | * Arithmetic Expansion |
| 47 | * <(list) and >(list) Process Substitution |
Eric Andersen | aac75e5 | 2001-04-30 18:18:45 +0000 | [diff] [blame] | 48 | * reserved words: case, esac, function |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 49 | * Here Documents ( << word ) |
| 50 | * Functions |
| 51 | * Major bugs: |
| 52 | * job handling woefully incomplete and buggy |
| 53 | * reserved word execution woefully incomplete and buggy |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 54 | * to-do: |
| 55 | * port selected bugfixes from post-0.49 busybox lash |
| 56 | * finish implementing reserved words |
| 57 | * handle children going into background |
| 58 | * clean up recognition of null pipes |
| 59 | * have builtin_exec set flag to avoid restore_redirects |
| 60 | * figure out if "echo foo}" is fixable |
| 61 | * check setting of global_argc and global_argv |
| 62 | * control-C handling, probably with longjmp |
| 63 | * VAR=value prefix for simple commands |
| 64 | * follow IFS rules more precisely, including update semantics |
| 65 | * write builtin_eval, builtin_ulimit, builtin_umask |
| 66 | * figure out what to do with backslash-newline |
| 67 | * explain why we use signal instead of sigaction |
| 68 | * propagate syntax errors, die on resource errors? |
| 69 | * continuation lines, both explicit and implicit - done? |
| 70 | * memory leak finding and plugging - done? |
| 71 | * more testing, especially quoting rules and redirection |
| 72 | * maybe change map[] to use 2-bit entries |
| 73 | * (eventually) remove all the printf's |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 74 | * |
| 75 | * This program is free software; you can redistribute it and/or modify |
| 76 | * it under the terms of the GNU General Public License as published by |
| 77 | * the Free Software Foundation; either version 2 of the License, or |
| 78 | * (at your option) any later version. |
| 79 | * |
| 80 | * This program is distributed in the hope that it will be useful, |
| 81 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 82 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 83 | * General Public License for more details. |
| 84 | * |
| 85 | * You should have received a copy of the GNU General Public License |
| 86 | * along with this program; if not, write to the Free Software |
| 87 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 88 | */ |
| 89 | #include <ctype.h> /* isalpha, isdigit */ |
| 90 | #include <unistd.h> /* getpid */ |
| 91 | #include <stdlib.h> /* getenv, atoi */ |
| 92 | #include <string.h> /* strchr */ |
| 93 | #include <stdio.h> /* popen etc. */ |
| 94 | #include <glob.h> /* glob, of course */ |
| 95 | #include <stdarg.h> /* va_list */ |
| 96 | #include <errno.h> |
| 97 | #include <fcntl.h> |
| 98 | #include <getopt.h> /* should be pretty obvious */ |
| 99 | |
| 100 | #include <sys/types.h> |
| 101 | #include <sys/wait.h> |
| 102 | #include <signal.h> |
| 103 | |
| 104 | /* #include <dmalloc.h> */ |
Eric Andersen | 4ed5e37 | 2001-05-01 01:49:50 +0000 | [diff] [blame^] | 105 | /* #define DEBUG_SHELL */ |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 106 | |
| 107 | #ifdef BB_VER |
| 108 | #include "busybox.h" |
| 109 | #include "cmdedit.h" |
| 110 | #else |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 111 | #define applet_name "hush" |
Eric Andersen | af44a0e | 2001-04-27 07:26:12 +0000 | [diff] [blame] | 112 | #include "standalone.h" |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 113 | #define shell_main main |
Eric Andersen | af44a0e | 2001-04-27 07:26:12 +0000 | [diff] [blame] | 114 | #define BB_FEATURE_SH_SIMPLE_PROMPT |
| 115 | #endif |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 116 | |
| 117 | typedef enum { |
| 118 | REDIRECT_INPUT = 1, |
| 119 | REDIRECT_OVERWRITE = 2, |
| 120 | REDIRECT_APPEND = 3, |
| 121 | REDIRECT_HEREIS = 4, |
| 122 | REDIRECT_IO = 5 |
| 123 | } redir_type; |
| 124 | |
| 125 | /* The descrip member of this structure is only used to make debugging |
| 126 | * output pretty */ |
| 127 | struct {int mode; int default_fd; char *descrip;} redir_table[] = { |
| 128 | { 0, 0, "()" }, |
| 129 | { O_RDONLY, 0, "<" }, |
| 130 | { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" }, |
| 131 | { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" }, |
| 132 | { O_RDONLY, -1, "<<" }, |
| 133 | { O_RDWR, 1, "<>" } |
| 134 | }; |
| 135 | |
| 136 | typedef enum { |
| 137 | PIPE_SEQ = 1, |
| 138 | PIPE_AND = 2, |
| 139 | PIPE_OR = 3, |
| 140 | PIPE_BG = 4, |
| 141 | } pipe_style; |
| 142 | |
| 143 | /* might eventually control execution */ |
| 144 | typedef enum { |
| 145 | RES_NONE = 0, |
| 146 | RES_IF = 1, |
| 147 | RES_THEN = 2, |
| 148 | RES_ELIF = 3, |
| 149 | RES_ELSE = 4, |
| 150 | RES_FI = 5, |
| 151 | RES_FOR = 6, |
| 152 | RES_WHILE = 7, |
| 153 | RES_UNTIL = 8, |
| 154 | RES_DO = 9, |
| 155 | RES_DONE = 10, |
Eric Andersen | af44a0e | 2001-04-27 07:26:12 +0000 | [diff] [blame] | 156 | RES_XXXX = 11, |
| 157 | RES_SNTX = 12 |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 158 | } reserved_style; |
| 159 | #define FLAG_END (1<<RES_NONE) |
| 160 | #define FLAG_IF (1<<RES_IF) |
| 161 | #define FLAG_THEN (1<<RES_THEN) |
| 162 | #define FLAG_ELIF (1<<RES_ELIF) |
| 163 | #define FLAG_ELSE (1<<RES_ELSE) |
| 164 | #define FLAG_FI (1<<RES_FI) |
| 165 | #define FLAG_FOR (1<<RES_FOR) |
| 166 | #define FLAG_WHILE (1<<RES_WHILE) |
| 167 | #define FLAG_UNTIL (1<<RES_UNTIL) |
| 168 | #define FLAG_DO (1<<RES_DO) |
| 169 | #define FLAG_DONE (1<<RES_DONE) |
| 170 | #define FLAG_START (1<<RES_XXXX) |
| 171 | |
| 172 | /* This holds pointers to the various results of parsing */ |
| 173 | struct p_context { |
| 174 | struct child_prog *child; |
| 175 | struct pipe *list_head; |
| 176 | struct pipe *pipe; |
| 177 | struct redir_struct *pending_redirect; |
| 178 | reserved_style w; |
| 179 | int old_flag; /* for figuring out valid reserved words */ |
| 180 | struct p_context *stack; |
| 181 | /* How about quoting status? */ |
| 182 | }; |
| 183 | |
| 184 | struct redir_struct { |
| 185 | redir_type type; /* type of redirection */ |
| 186 | int fd; /* file descriptor being redirected */ |
| 187 | int dup; /* -1, or file descriptor being duplicated */ |
| 188 | struct redir_struct *next; /* pointer to the next redirect in the list */ |
| 189 | glob_t word; /* *word.gl_pathv is the filename */ |
| 190 | }; |
| 191 | |
| 192 | struct child_prog { |
| 193 | pid_t pid; /* 0 if exited */ |
| 194 | char **argv; /* program name and arguments */ |
| 195 | struct pipe *group; /* if non-NULL, first in group or subshell */ |
| 196 | int subshell; /* flag, non-zero if group must be forked */ |
| 197 | struct redir_struct *redirects; /* I/O redirections */ |
| 198 | glob_t glob_result; /* result of parameter globbing */ |
| 199 | int is_stopped; /* is the program currently running? */ |
| 200 | struct pipe *family; /* pointer back to the child's parent pipe */ |
| 201 | }; |
| 202 | |
| 203 | struct pipe { |
| 204 | int jobid; /* job number */ |
| 205 | int num_progs; /* total number of programs in job */ |
| 206 | int running_progs; /* number of programs running */ |
| 207 | char *text; /* name of job */ |
| 208 | char *cmdbuf; /* buffer various argv's point into */ |
| 209 | pid_t pgrp; /* process group ID for the job */ |
| 210 | struct child_prog *progs; /* array of commands in pipe */ |
| 211 | struct pipe *next; /* to track background commands */ |
| 212 | int stopped_progs; /* number of programs alive, but stopped */ |
| 213 | int job_context; /* bitmask defining current context */ |
| 214 | pipe_style followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */ |
| 215 | reserved_style r_mode; /* supports if, for, while, until */ |
| 216 | struct jobset *job_list; |
| 217 | }; |
| 218 | |
| 219 | struct jobset { |
| 220 | struct pipe *head; /* head of list of running jobs */ |
| 221 | struct pipe *fg; /* current foreground job */ |
| 222 | }; |
| 223 | |
| 224 | struct close_me { |
| 225 | int fd; |
| 226 | struct close_me *next; |
| 227 | }; |
| 228 | |
| 229 | /* globals, connect us to the outside world |
| 230 | * the first three support $?, $#, and $1 */ |
| 231 | char **global_argv; |
| 232 | unsigned int global_argc; |
| 233 | unsigned int last_return_code; |
| 234 | extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */ |
| 235 | |
| 236 | /* Variables we export */ |
| 237 | unsigned int shell_context; /* Used in cmdedit.c to reset the |
| 238 | * context when someone hits ^C */ |
| 239 | |
| 240 | /* "globals" within this file */ |
| 241 | static char *ifs=NULL; |
| 242 | static char map[256]; |
| 243 | static int fake_mode=0; |
| 244 | static int interactive=0; |
| 245 | static struct close_me *close_me_head = NULL; |
| 246 | static char *cwd; |
Eric Andersen | af44a0e | 2001-04-27 07:26:12 +0000 | [diff] [blame] | 247 | /* static struct jobset job_list = { NULL, NULL }; */ |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 248 | static unsigned int last_bg_pid=0; |
| 249 | static char *PS1; |
| 250 | static char *PS2 = "> "; |
| 251 | |
| 252 | #define B_CHUNK (100) |
| 253 | #define B_NOSPAC 1 |
| 254 | #define MAX_LINE 256 /* for cwd */ |
| 255 | #define MAX_READ 256 /* for builtin_read */ |
| 256 | |
| 257 | typedef struct { |
| 258 | char *data; |
| 259 | int length; |
| 260 | int maxlen; |
| 261 | int quote; |
| 262 | int nonnull; |
| 263 | } o_string; |
| 264 | #define NULL_O_STRING {NULL,0,0,0,0} |
| 265 | /* used for initialization: |
| 266 | o_string foo = NULL_O_STRING; */ |
| 267 | |
| 268 | /* I can almost use ordinary FILE *. Is open_memstream() universally |
| 269 | * available? Where is it documented? */ |
| 270 | struct in_str { |
| 271 | const char *p; |
| 272 | int __promptme; |
| 273 | int promptmode; |
| 274 | FILE *file; |
| 275 | int (*get) (struct in_str *); |
| 276 | int (*peek) (struct in_str *); |
| 277 | }; |
| 278 | #define b_getch(input) ((input)->get(input)) |
| 279 | #define b_peek(input) ((input)->peek(input)) |
| 280 | |
| 281 | #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n" |
| 282 | |
| 283 | struct built_in_command { |
| 284 | char *cmd; /* name */ |
| 285 | char *descr; /* description */ |
| 286 | int (*function) (struct child_prog *); /* function ptr */ |
| 287 | }; |
| 288 | |
| 289 | /* belongs in busybox.h */ |
| 290 | static inline int max(int a, int b) { |
| 291 | return (a>b)?a:b; |
| 292 | } |
| 293 | |
| 294 | /* This should be in utility.c */ |
| 295 | #ifdef DEBUG_SHELL |
| 296 | static void debug_printf(const char *format, ...) |
| 297 | { |
| 298 | va_list args; |
| 299 | va_start(args, format); |
| 300 | vfprintf(stderr, format, args); |
| 301 | va_end(args); |
| 302 | } |
| 303 | #else |
| 304 | static void debug_printf(const char *format, ...) { } |
| 305 | #endif |
| 306 | #define final_printf debug_printf |
| 307 | |
| 308 | void __syntax(char *file, int line) { |
| 309 | fprintf(stderr,"syntax error %s:%d\n",file,line); |
| 310 | } |
| 311 | #define syntax() __syntax(__FILE__, __LINE__) |
| 312 | |
| 313 | /* Index of subroutines: */ |
| 314 | /* function prototypes for builtins */ |
| 315 | static int builtin_cd(struct child_prog *child); |
| 316 | static int builtin_env(struct child_prog *child); |
| 317 | static int builtin_exec(struct child_prog *child); |
| 318 | static int builtin_exit(struct child_prog *child); |
| 319 | static int builtin_export(struct child_prog *child); |
| 320 | static int builtin_fg_bg(struct child_prog *child); |
| 321 | static int builtin_help(struct child_prog *child); |
| 322 | static int builtin_jobs(struct child_prog *child); |
| 323 | static int builtin_pwd(struct child_prog *child); |
| 324 | static int builtin_read(struct child_prog *child); |
| 325 | static int builtin_shift(struct child_prog *child); |
| 326 | static int builtin_source(struct child_prog *child); |
| 327 | static int builtin_ulimit(struct child_prog *child); |
| 328 | static int builtin_umask(struct child_prog *child); |
| 329 | static int builtin_unset(struct child_prog *child); |
| 330 | /* o_string manipulation: */ |
| 331 | static int b_check_space(o_string *o, int len); |
| 332 | static int b_addchr(o_string *o, int ch); |
| 333 | static void b_reset(o_string *o); |
| 334 | static int b_addqchr(o_string *o, int ch, int quote); |
| 335 | static int b_adduint(o_string *o, unsigned int i); |
| 336 | /* in_str manipulations: */ |
| 337 | static int static_get(struct in_str *i); |
| 338 | static int static_peek(struct in_str *i); |
| 339 | static int file_get(struct in_str *i); |
| 340 | static int file_peek(struct in_str *i); |
| 341 | static void setup_file_in_str(struct in_str *i, FILE *f); |
| 342 | static void setup_string_in_str(struct in_str *i, const char *s); |
| 343 | /* close_me manipulations: */ |
| 344 | static void mark_open(int fd); |
| 345 | static void mark_closed(int fd); |
| 346 | static void close_all(); |
| 347 | /* "run" the final data structures: */ |
| 348 | static char *indenter(int i); |
| 349 | static int run_list_test(struct pipe *head, int indent); |
| 350 | static int run_pipe_test(struct pipe *pi, int indent); |
| 351 | /* really run the final data structures: */ |
| 352 | static int setup_redirects(struct child_prog *prog, int squirrel[]); |
| 353 | static int pipe_wait(struct pipe *pi); |
| 354 | static int run_list_real(struct pipe *pi); |
| 355 | static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn)); |
| 356 | static int run_pipe_real(struct pipe *pi); |
| 357 | /* extended glob support: */ |
| 358 | static int globhack(const char *src, int flags, glob_t *pglob); |
| 359 | static int glob_needed(const char *s); |
| 360 | static int xglob(o_string *dest, int flags, glob_t *pglob); |
| 361 | /* data structure manipulation: */ |
| 362 | static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input); |
| 363 | static void initialize_context(struct p_context *ctx); |
| 364 | static int done_word(o_string *dest, struct p_context *ctx); |
| 365 | static int done_command(struct p_context *ctx); |
| 366 | static int done_pipe(struct p_context *ctx, pipe_style type); |
| 367 | /* primary string parsing: */ |
| 368 | static int redirect_dup_num(struct in_str *input); |
| 369 | static int redirect_opt_num(o_string *o); |
| 370 | static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end); |
| 371 | static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch); |
| 372 | static void lookup_param(o_string *dest, struct p_context *ctx, o_string *src); |
| 373 | static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input); |
| 374 | static int parse_string(o_string *dest, struct p_context *ctx, const char *src); |
| 375 | static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger); |
| 376 | /* setup: */ |
| 377 | static int parse_stream_outer(struct in_str *inp); |
| 378 | static int parse_string_outer(const char *s); |
| 379 | static int parse_file_outer(FILE *f); |
| 380 | |
| 381 | /* Table of built-in functions. They can be forked or not, depending on |
| 382 | * context: within pipes, they fork. As simple commands, they do not. |
| 383 | * When used in non-forking context, they can change global variables |
| 384 | * in the parent shell process. If forked, of course they can not. |
| 385 | * For example, 'unset foo | whatever' will parse and run, but foo will |
| 386 | * still be set at the end. */ |
| 387 | static struct built_in_command bltins[] = { |
| 388 | {"bg", "Resume a job in the background", builtin_fg_bg}, |
| 389 | {"cd", "Change working directory", builtin_cd}, |
| 390 | {"env", "Print all environment variables", builtin_env}, |
| 391 | {"exec", "Exec command, replacing this shell with the exec'd process", builtin_exec}, |
| 392 | {"exit", "Exit from shell()", builtin_exit}, |
| 393 | {"export", "Set environment variable", builtin_export}, |
| 394 | {"fg", "Bring job into the foreground", builtin_fg_bg}, |
| 395 | {"jobs", "Lists the active jobs", builtin_jobs}, |
| 396 | {"pwd", "Print current directory", builtin_pwd}, |
| 397 | {"read", "Input environment variable", builtin_read}, |
| 398 | {"shift", "Shift positional parameters", builtin_shift}, |
| 399 | {"ulimit","Controls resource limits", builtin_ulimit}, |
| 400 | {"umask","Sets file creation mask", builtin_umask}, |
| 401 | {"unset", "Unset environment variable", builtin_unset}, |
| 402 | {".", "Source-in and run commands in a file", builtin_source}, |
| 403 | {"help", "List shell built-in commands", builtin_help}, |
| 404 | {NULL, NULL, NULL} |
| 405 | }; |
| 406 | |
| 407 | /* built-in 'cd <path>' handler */ |
| 408 | static int builtin_cd(struct child_prog *child) |
| 409 | { |
| 410 | char *newdir; |
| 411 | if (child->argv[1] == NULL) |
| 412 | newdir = getenv("HOME"); |
| 413 | else |
| 414 | newdir = child->argv[1]; |
| 415 | if (chdir(newdir)) { |
| 416 | printf("cd: %s: %s\n", newdir, strerror(errno)); |
| 417 | return EXIT_FAILURE; |
| 418 | } |
| 419 | getcwd(cwd, sizeof(char)*MAX_LINE); |
| 420 | return EXIT_SUCCESS; |
| 421 | } |
| 422 | |
| 423 | /* built-in 'env' handler */ |
| 424 | static int builtin_env(struct child_prog *dummy) |
| 425 | { |
| 426 | char **e = environ; |
| 427 | if (e == NULL) return EXIT_FAILURE; |
| 428 | for (; *e; e++) { |
| 429 | puts(*e); |
| 430 | } |
| 431 | return EXIT_SUCCESS; |
| 432 | } |
| 433 | |
| 434 | /* built-in 'exec' handler */ |
| 435 | static int builtin_exec(struct child_prog *child) |
| 436 | { |
| 437 | if (child->argv[1] == NULL) |
| 438 | return EXIT_SUCCESS; /* Really? */ |
| 439 | child->argv++; |
| 440 | pseudo_exec(child); |
| 441 | /* never returns */ |
| 442 | } |
| 443 | |
| 444 | /* built-in 'exit' handler */ |
| 445 | static int builtin_exit(struct child_prog *child) |
| 446 | { |
| 447 | if (child->argv[1] == NULL) |
| 448 | exit(EXIT_SUCCESS); |
| 449 | exit (atoi(child->argv[1])); |
| 450 | } |
| 451 | |
| 452 | /* built-in 'export VAR=value' handler */ |
| 453 | static int builtin_export(struct child_prog *child) |
| 454 | { |
| 455 | int res; |
| 456 | |
| 457 | if (child->argv[1] == NULL) { |
| 458 | return (builtin_env(child)); |
| 459 | } |
| 460 | res = putenv(child->argv[1]); |
| 461 | if (res) |
| 462 | fprintf(stderr, "export: %s\n", strerror(errno)); |
| 463 | return (res); |
| 464 | } |
| 465 | |
| 466 | /* built-in 'fg' and 'bg' handler */ |
| 467 | static int builtin_fg_bg(struct child_prog *child) |
| 468 | { |
| 469 | int i, jobNum; |
| 470 | struct pipe *job=NULL; |
| 471 | |
| 472 | if (!child->argv[1] || child->argv[2]) { |
| 473 | error_msg("%s: exactly one argument is expected\n", |
| 474 | child->argv[0]); |
| 475 | return EXIT_FAILURE; |
| 476 | } |
| 477 | |
| 478 | if (sscanf(child->argv[1], "%%%d", &jobNum) != 1) { |
| 479 | error_msg("%s: bad argument '%s'\n", |
| 480 | child->argv[0], child->argv[1]); |
| 481 | return EXIT_FAILURE; |
| 482 | } |
| 483 | |
| 484 | for (job = child->family->job_list->head; job; job = job->next) { |
| 485 | if (job->jobid == jobNum) { |
| 486 | break; |
| 487 | } |
| 488 | } |
| 489 | |
| 490 | if (!job) { |
| 491 | error_msg("%s: unknown job %d\n", |
| 492 | child->argv[0], jobNum); |
| 493 | return EXIT_FAILURE; |
| 494 | } |
| 495 | |
| 496 | if (*child->argv[0] == 'f') { |
| 497 | /* Make this job the foreground job */ |
| 498 | /* suppress messages when run from /linuxrc mag@sysgo.de */ |
| 499 | if (tcsetpgrp(0, job->pgrp) && errno != ENOTTY) |
| 500 | perror_msg("tcsetpgrp"); |
| 501 | child->family->job_list->fg = job; |
| 502 | } |
| 503 | |
| 504 | /* Restart the processes in the job */ |
| 505 | for (i = 0; i < job->num_progs; i++) |
| 506 | job->progs[i].is_stopped = 0; |
| 507 | |
| 508 | kill(-job->pgrp, SIGCONT); |
| 509 | |
| 510 | job->stopped_progs = 0; |
| 511 | return EXIT_SUCCESS; |
| 512 | } |
| 513 | |
| 514 | /* built-in 'help' handler */ |
| 515 | static int builtin_help(struct child_prog *dummy) |
| 516 | { |
| 517 | struct built_in_command *x; |
| 518 | |
| 519 | printf("\nBuilt-in commands:\n"); |
| 520 | printf("-------------------\n"); |
| 521 | for (x = bltins; x->cmd; x++) { |
| 522 | if (x->descr==NULL) |
| 523 | continue; |
| 524 | printf("%s\t%s\n", x->cmd, x->descr); |
| 525 | } |
| 526 | printf("\n\n"); |
| 527 | return EXIT_SUCCESS; |
| 528 | } |
| 529 | |
| 530 | /* built-in 'jobs' handler */ |
| 531 | static int builtin_jobs(struct child_prog *child) |
| 532 | { |
| 533 | struct pipe *job; |
| 534 | char *status_string; |
| 535 | |
| 536 | for (job = child->family->job_list->head; job; job = job->next) { |
| 537 | if (job->running_progs == job->stopped_progs) |
| 538 | status_string = "Stopped"; |
| 539 | else |
| 540 | status_string = "Running"; |
| 541 | printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text); |
| 542 | } |
| 543 | return EXIT_SUCCESS; |
| 544 | } |
| 545 | |
| 546 | |
| 547 | /* built-in 'pwd' handler */ |
| 548 | static int builtin_pwd(struct child_prog *dummy) |
| 549 | { |
| 550 | getcwd(cwd, MAX_LINE); |
| 551 | puts(cwd); |
| 552 | return EXIT_SUCCESS; |
| 553 | } |
| 554 | |
| 555 | /* built-in 'read VAR' handler */ |
| 556 | static int builtin_read(struct child_prog *child) |
| 557 | { |
| 558 | int res = 0, len, newlen; |
| 559 | char *s; |
| 560 | char string[MAX_READ]; |
| 561 | |
| 562 | if (child->argv[1]) { |
| 563 | /* argument (VAR) given: put "VAR=" into buffer */ |
| 564 | strcpy(string, child->argv[1]); |
| 565 | len = strlen(string); |
| 566 | string[len++] = '='; |
| 567 | string[len] = '\0'; |
| 568 | /* XXX would it be better to go through in_str? */ |
| 569 | fgets(&string[len], sizeof(string) - len, stdin); /* read string */ |
| 570 | newlen = strlen(string); |
| 571 | if(newlen > len) |
| 572 | string[--newlen] = '\0'; /* chomp trailing newline */ |
| 573 | /* |
| 574 | ** string should now contain "VAR=<value>" |
| 575 | ** copy it (putenv() won't do that, so we must make sure |
| 576 | ** the string resides in a static buffer!) |
| 577 | */ |
| 578 | res = -1; |
| 579 | if((s = strdup(string))) |
| 580 | res = putenv(s); |
| 581 | if (res) |
| 582 | fprintf(stderr, "read: %s\n", strerror(errno)); |
| 583 | } |
| 584 | else |
| 585 | fgets(string, sizeof(string), stdin); |
| 586 | |
| 587 | return (res); |
| 588 | } |
| 589 | |
| 590 | /* Built-in 'shift' handler */ |
| 591 | static int builtin_shift(struct child_prog *child) |
| 592 | { |
| 593 | int n=1; |
| 594 | if (child->argv[1]) { |
| 595 | n=atoi(child->argv[1]); |
| 596 | } |
| 597 | if (n>=0 && n<global_argc) { |
| 598 | /* XXX This probably breaks $0 */ |
| 599 | global_argc -= n; |
| 600 | global_argv += n; |
| 601 | return EXIT_SUCCESS; |
| 602 | } else { |
| 603 | return EXIT_FAILURE; |
| 604 | } |
| 605 | } |
| 606 | |
| 607 | /* Built-in '.' handler (read-in and execute commands from file) */ |
| 608 | static int builtin_source(struct child_prog *child) |
| 609 | { |
| 610 | FILE *input; |
| 611 | int status; |
| 612 | |
| 613 | if (child->argv[1] == NULL) |
| 614 | return EXIT_FAILURE; |
| 615 | |
| 616 | /* XXX search through $PATH is missing */ |
| 617 | input = fopen(child->argv[1], "r"); |
| 618 | if (!input) { |
| 619 | fprintf(stderr, "Couldn't open file '%s'\n", child->argv[1]); |
| 620 | return EXIT_FAILURE; |
| 621 | } |
| 622 | |
| 623 | /* Now run the file */ |
| 624 | /* XXX argv and argc are broken; need to save old global_argv |
| 625 | * (pointer only is OK!) on this stack frame, |
| 626 | * set global_argv=child->argv+1, recurse, and restore. */ |
| 627 | mark_open(fileno(input)); |
| 628 | status = parse_file_outer(input); |
| 629 | mark_closed(fileno(input)); |
| 630 | fclose(input); |
| 631 | return (status); |
| 632 | } |
| 633 | |
| 634 | static int builtin_ulimit(struct child_prog *child) |
| 635 | { |
| 636 | printf("builtin_ulimit not written\n"); |
| 637 | return EXIT_FAILURE; |
| 638 | } |
| 639 | |
| 640 | static int builtin_umask(struct child_prog *child) |
| 641 | { |
| 642 | printf("builtin_umask not written\n"); |
| 643 | return EXIT_FAILURE; |
| 644 | } |
| 645 | |
| 646 | /* built-in 'unset VAR' handler */ |
| 647 | static int builtin_unset(struct child_prog *child) |
| 648 | { |
| 649 | if (child->argv[1] == NULL) { |
| 650 | fprintf(stderr, "unset: parameter required.\n"); |
| 651 | return EXIT_FAILURE; |
| 652 | } |
| 653 | unsetenv(child->argv[1]); |
| 654 | return EXIT_SUCCESS; |
| 655 | } |
| 656 | |
| 657 | static int b_check_space(o_string *o, int len) |
| 658 | { |
| 659 | /* It would be easy to drop a more restrictive policy |
| 660 | * in here, such as setting a maximum string length */ |
| 661 | if (o->length + len > o->maxlen) { |
| 662 | char *old_data = o->data; |
| 663 | /* assert (data == NULL || o->maxlen != 0); */ |
| 664 | o->maxlen += max(2*len, B_CHUNK); |
| 665 | o->data = realloc(o->data, 1 + o->maxlen); |
| 666 | if (o->data == NULL) { |
| 667 | free(old_data); |
| 668 | } |
| 669 | } |
| 670 | return o->data == NULL; |
| 671 | } |
| 672 | |
| 673 | static int b_addchr(o_string *o, int ch) |
| 674 | { |
| 675 | debug_printf("b_addchr: %c %d %p\n", ch, o->length, o); |
| 676 | if (b_check_space(o, 1)) return B_NOSPAC; |
| 677 | o->data[o->length] = ch; |
| 678 | o->length++; |
| 679 | o->data[o->length] = '\0'; |
| 680 | return 0; |
| 681 | } |
| 682 | |
| 683 | static void b_reset(o_string *o) |
| 684 | { |
| 685 | o->length = 0; |
| 686 | o->nonnull = 0; |
| 687 | if (o->data != NULL) *o->data = '\0'; |
| 688 | } |
| 689 | |
| 690 | static void b_free(o_string *o) |
| 691 | { |
| 692 | b_reset(o); |
| 693 | if (o->data != NULL) free(o->data); |
| 694 | o->data = NULL; |
| 695 | o->maxlen = 0; |
| 696 | } |
| 697 | |
| 698 | /* My analysis of quoting semantics tells me that state information |
| 699 | * is associated with a destination, not a source. |
| 700 | */ |
| 701 | static int b_addqchr(o_string *o, int ch, int quote) |
| 702 | { |
| 703 | if (quote && strchr("*?[\\",ch)) { |
| 704 | int rc; |
| 705 | rc = b_addchr(o, '\\'); |
| 706 | if (rc) return rc; |
| 707 | } |
| 708 | return b_addchr(o, ch); |
| 709 | } |
| 710 | |
| 711 | /* belongs in utility.c */ |
| 712 | char *simple_itoa(unsigned int i) |
| 713 | { |
| 714 | /* 21 digits plus null terminator, good for 64-bit or smaller ints */ |
| 715 | static char local[22]; |
| 716 | char *p = &local[21]; |
| 717 | *p-- = '\0'; |
| 718 | do { |
| 719 | *p-- = '0' + i % 10; |
| 720 | i /= 10; |
| 721 | } while (i > 0); |
| 722 | return p + 1; |
| 723 | } |
| 724 | |
| 725 | static int b_adduint(o_string *o, unsigned int i) |
| 726 | { |
| 727 | int r; |
| 728 | char *p = simple_itoa(i); |
| 729 | /* no escape checking necessary */ |
| 730 | do r=b_addchr(o, *p++); while (r==0 && *p); |
| 731 | return r; |
| 732 | } |
| 733 | |
| 734 | static int static_get(struct in_str *i) |
| 735 | { |
| 736 | int ch=*i->p++; |
| 737 | if (ch=='\0') return EOF; |
| 738 | return ch; |
| 739 | } |
| 740 | |
| 741 | static int static_peek(struct in_str *i) |
| 742 | { |
| 743 | return *i->p; |
| 744 | } |
| 745 | |
| 746 | static inline void cmdedit_set_initial_prompt(void) |
| 747 | { |
| 748 | #ifdef BB_FEATURE_SH_SIMPLE_PROMPT |
| 749 | PS1 = NULL; |
| 750 | #else |
| 751 | PS1 = getenv("PS1"); |
| 752 | if(PS1==0) |
| 753 | PS1 = "\\w \\$ "; |
| 754 | #endif |
| 755 | } |
| 756 | |
| 757 | static inline void setup_prompt_string(int promptmode, char **prompt_str) |
| 758 | { |
Eric Andersen | af44a0e | 2001-04-27 07:26:12 +0000 | [diff] [blame] | 759 | debug_printf("setup_prompt_string %d ",promptmode); |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 760 | #ifdef BB_FEATURE_SH_SIMPLE_PROMPT |
| 761 | /* Set up the prompt */ |
| 762 | if (promptmode == 1) { |
| 763 | if (PS1) |
| 764 | free(PS1); |
| 765 | PS1=xmalloc(strlen(cwd)+4); |
| 766 | sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ? "$ ":"# "); |
| 767 | *prompt_str = PS1; |
| 768 | } else { |
| 769 | *prompt_str = PS2; |
| 770 | } |
| 771 | #else |
| 772 | *prompt_str = (promptmode==0)? PS1 : PS2; |
Eric Andersen | af44a0e | 2001-04-27 07:26:12 +0000 | [diff] [blame] | 773 | #endif |
| 774 | debug_printf("result %s\n",*prompt_str); |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 775 | } |
| 776 | |
| 777 | static void get_user_input(struct in_str *i) |
| 778 | { |
| 779 | char *prompt_str; |
Eric Andersen | 088875f | 2001-04-27 07:49:41 +0000 | [diff] [blame] | 780 | static char the_command[BUFSIZ]; |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 781 | |
| 782 | setup_prompt_string(i->promptmode, &prompt_str); |
| 783 | #ifdef BB_FEATURE_COMMAND_EDITING |
| 784 | /* |
| 785 | ** enable command line editing only while a command line |
| 786 | ** is actually being read; otherwise, we'll end up bequeathing |
| 787 | ** atexit() handlers and other unwanted stuff to our |
| 788 | ** child processes (rob@sysgo.de) |
| 789 | */ |
| 790 | cmdedit_read_input(prompt_str, the_command); |
| 791 | cmdedit_terminate(); |
| 792 | #else |
| 793 | fputs(prompt_str, stdout); |
| 794 | fflush(stdout); |
| 795 | the_command[0]=fgetc(i->file); |
| 796 | the_command[1]='\0'; |
| 797 | #endif |
| 798 | i->p = the_command; |
| 799 | } |
| 800 | |
| 801 | /* This is the magic location that prints prompts |
| 802 | * and gets data back from the user */ |
| 803 | static int file_get(struct in_str *i) |
| 804 | { |
| 805 | int ch; |
| 806 | |
| 807 | ch = 0; |
| 808 | /* If there is data waiting, eat it up */ |
| 809 | if (i->p && *i->p) { |
| 810 | ch=*i->p++; |
| 811 | } else { |
| 812 | /* need to double check i->file because we might be doing something |
| 813 | * more complicated by now, like sourcing or substituting. */ |
| 814 | if (i->__promptme && interactive && i->file == stdin) { |
| 815 | get_user_input(i); |
| 816 | i->promptmode=2; |
Eric Andersen | 4ed5e37 | 2001-05-01 01:49:50 +0000 | [diff] [blame^] | 817 | } else { |
| 818 | static char buffer; |
| 819 | buffer = fgetc(i->file); |
| 820 | i->p = &buffer; |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 821 | } |
Eric Andersen | 4ed5e37 | 2001-05-01 01:49:50 +0000 | [diff] [blame^] | 822 | |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 823 | i->__promptme = 0; |
| 824 | |
| 825 | if (i->p && *i->p) { |
| 826 | ch=*i->p++; |
| 827 | } |
| 828 | debug_printf("b_getch: got a %d\n", ch); |
| 829 | } |
| 830 | if (ch == '\n') i->__promptme=1; |
| 831 | return ch; |
| 832 | } |
| 833 | |
| 834 | /* All the callers guarantee this routine will never be |
| 835 | * used right after a newline, so prompting is not needed. |
| 836 | */ |
| 837 | static int file_peek(struct in_str *i) |
| 838 | { |
| 839 | if (i->p && *i->p) { |
| 840 | return *i->p; |
| 841 | } else { |
| 842 | static char buffer; |
| 843 | buffer = fgetc(i->file); |
| 844 | i->p = &buffer; |
| 845 | debug_printf("b_peek: got a %d\n", *i->p); |
| 846 | return *i->p; |
| 847 | } |
| 848 | } |
| 849 | |
| 850 | static void setup_file_in_str(struct in_str *i, FILE *f) |
| 851 | { |
| 852 | i->peek = file_peek; |
| 853 | i->get = file_get; |
| 854 | i->__promptme=1; |
| 855 | i->promptmode=1; |
| 856 | i->file = f; |
| 857 | i->p = NULL; |
| 858 | } |
| 859 | |
| 860 | static void setup_string_in_str(struct in_str *i, const char *s) |
| 861 | { |
| 862 | i->peek = static_peek; |
| 863 | i->get = static_get; |
| 864 | i->__promptme=1; |
| 865 | i->promptmode=1; |
| 866 | i->p = s; |
| 867 | } |
| 868 | |
| 869 | static void mark_open(int fd) |
| 870 | { |
| 871 | struct close_me *new = xmalloc(sizeof(struct close_me)); |
| 872 | new->fd = fd; |
| 873 | new->next = close_me_head; |
| 874 | close_me_head = new; |
| 875 | } |
| 876 | |
| 877 | static void mark_closed(int fd) |
| 878 | { |
| 879 | struct close_me *tmp; |
| 880 | if (close_me_head == NULL || close_me_head->fd != fd) |
| 881 | error_msg_and_die("corrupt close_me"); |
| 882 | tmp = close_me_head; |
| 883 | close_me_head = close_me_head->next; |
| 884 | free(tmp); |
| 885 | } |
| 886 | |
| 887 | static void close_all() |
| 888 | { |
| 889 | struct close_me *c; |
| 890 | for (c=close_me_head; c; c=c->next) { |
| 891 | close(c->fd); |
| 892 | } |
| 893 | close_me_head = NULL; |
| 894 | } |
| 895 | |
| 896 | /* squirrel != NULL means we squirrel away copies of stdin, stdout, |
| 897 | * and stderr if they are redirected. */ |
| 898 | static int setup_redirects(struct child_prog *prog, int squirrel[]) |
| 899 | { |
| 900 | int openfd, mode; |
| 901 | struct redir_struct *redir; |
| 902 | |
| 903 | for (redir=prog->redirects; redir; redir=redir->next) { |
| 904 | if (redir->dup == -1) { |
| 905 | mode=redir_table[redir->type].mode; |
| 906 | openfd = open(redir->word.gl_pathv[0], mode, 0666); |
| 907 | if (openfd < 0) { |
| 908 | /* this could get lost if stderr has been redirected, but |
| 909 | bash and ash both lose it as well (though zsh doesn't!) */ |
| 910 | fprintf(stderr,"error opening %s: %s\n", redir->word.gl_pathv[0], |
| 911 | strerror(errno)); |
| 912 | return 1; |
| 913 | } |
| 914 | } else { |
| 915 | openfd = redir->dup; |
| 916 | } |
| 917 | |
| 918 | if (openfd != redir->fd) { |
| 919 | if (squirrel && redir->fd < 3) { |
| 920 | squirrel[redir->fd] = dup(redir->fd); |
| 921 | } |
| 922 | dup2(openfd, redir->fd); |
| 923 | close(openfd); |
| 924 | } |
| 925 | } |
| 926 | return 0; |
| 927 | } |
| 928 | |
| 929 | static void restore_redirects(int squirrel[]) |
| 930 | { |
| 931 | int i, fd; |
| 932 | for (i=0; i<3; i++) { |
| 933 | fd = squirrel[i]; |
| 934 | if (fd != -1) { |
| 935 | /* No error checking. I sure wouldn't know what |
| 936 | * to do with an error if I found one! */ |
| 937 | dup2(fd, i); |
| 938 | close(fd); |
| 939 | } |
| 940 | } |
| 941 | } |
| 942 | |
| 943 | /* XXX this definitely needs some more thought, work, and |
| 944 | * cribbing from other shells */ |
| 945 | static int pipe_wait(struct pipe *pi) |
| 946 | { |
| 947 | int rcode=0, i, pid, running, status; |
| 948 | running = pi->num_progs; |
| 949 | while (running) { |
| 950 | pid=waitpid(-1, &status, 0); |
| 951 | if (pid < 0) perror_msg_and_die("waitpid"); |
| 952 | for (i=0; i < pi->num_progs; i++) { |
| 953 | if (pi->progs[i].pid == pid) { |
| 954 | if (i==pi->num_progs-1) rcode=WEXITSTATUS(status); |
| 955 | pi->progs[i].pid = 0; |
| 956 | running--; |
| 957 | break; |
| 958 | } |
| 959 | } |
| 960 | } |
| 961 | return rcode; |
| 962 | } |
| 963 | |
| 964 | /* very simple version for testing */ |
| 965 | static void pseudo_exec(struct child_prog *child) |
| 966 | { |
| 967 | int rcode; |
| 968 | struct built_in_command *x; |
| 969 | if (child->argv) { |
| 970 | /* |
| 971 | * Check if the command matches any of the builtins. |
| 972 | * Depending on context, this might be redundant. But it's |
| 973 | * easier to waste a few CPU cycles than it is to figure out |
| 974 | * if this is one of those cases. |
| 975 | */ |
| 976 | for (x = bltins; x->cmd; x++) { |
| 977 | if (strcmp(child->argv[0], x->cmd) == 0 ) { |
| 978 | debug_printf("builtin exec %s\n", child->argv[0]); |
| 979 | exit(x->function(child)); |
| 980 | } |
| 981 | } |
Eric Andersen | aac75e5 | 2001-04-30 18:18:45 +0000 | [diff] [blame] | 982 | |
| 983 | /* Check if the command matches any busybox internal commands |
| 984 | * ("applets") here. |
| 985 | * FIXME: This feature is not 100% safe, since |
| 986 | * BusyBox is not fully reentrant, so we have no guarantee the things |
| 987 | * from the .bss are still zeroed, or that things from .data are still |
| 988 | * at their defaults. We could exec ourself from /proc/self/exe, but I |
| 989 | * really dislike relying on /proc for things. We could exec ourself |
| 990 | * from global_argv[0], but if we are in a chroot, we may not be able |
| 991 | * to find ourself... */ |
| 992 | #ifdef BB_FEATURE_SH_STANDALONE_SHELL |
| 993 | { |
| 994 | int argc_l; |
| 995 | char** argv_l=child->argv; |
| 996 | char *name = child->argv[0]; |
| 997 | |
| 998 | #ifdef BB_FEATURE_SH_APPLETS_ALWAYS_WIN |
| 999 | /* Following discussions from November 2000 on the busybox mailing |
| 1000 | * list, the default configuration, (without |
| 1001 | * get_last_path_component()) lets the user force use of an |
| 1002 | * external command by specifying the full (with slashes) filename. |
| 1003 | * If you enable BB_FEATURE_SH_APPLETS_ALWAYS_WIN, then applets |
| 1004 | * _aways_ override external commands, so if you want to run |
| 1005 | * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the |
| 1006 | * filesystem and is _not_ busybox. Some systems may want this, |
| 1007 | * most do not. */ |
| 1008 | name = get_last_path_component(name); |
| 1009 | #endif |
| 1010 | /* Count argc for use in a second... */ |
| 1011 | for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++); |
| 1012 | optind = 1; |
| 1013 | debug_printf("running applet %s\n", name); |
| 1014 | run_applet_by_name(name, argc_l, child->argv); |
| 1015 | exit(1); |
| 1016 | } |
| 1017 | #endif |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 1018 | debug_printf("exec of %s\n",child->argv[0]); |
| 1019 | execvp(child->argv[0],child->argv); |
| 1020 | perror("execvp"); |
| 1021 | exit(1); |
| 1022 | } else if (child->group) { |
| 1023 | debug_printf("runtime nesting to group\n"); |
| 1024 | interactive=0; /* crucial!!!! */ |
| 1025 | rcode = run_list_real(child->group); |
| 1026 | /* OK to leak memory by not calling run_list_test, |
| 1027 | * since this process is about to exit */ |
| 1028 | exit(rcode); |
| 1029 | } else { |
| 1030 | /* Can happen. See what bash does with ">foo" by itself. */ |
| 1031 | debug_printf("trying to pseudo_exec null command\n"); |
| 1032 | exit(EXIT_SUCCESS); |
| 1033 | } |
| 1034 | } |
| 1035 | |
| 1036 | /* run_pipe_real() starts all the jobs, but doesn't wait for anything |
| 1037 | * to finish. See pipe_wait(). |
| 1038 | * |
| 1039 | * return code is normally -1, when the caller has to wait for children |
| 1040 | * to finish to determine the exit status of the pipe. If the pipe |
| 1041 | * is a simple builtin command, however, the action is done by the |
| 1042 | * time run_pipe_real returns, and the exit code is provided as the |
| 1043 | * return value. |
| 1044 | * |
| 1045 | * The input of the pipe is always stdin, the output is always |
| 1046 | * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus, |
| 1047 | * because it tries to avoid running the command substitution in |
| 1048 | * subshell, when that is in fact necessary. The subshell process |
| 1049 | * now has its stdout directed to the input of the appropriate pipe, |
| 1050 | * so this routine is noticeably simpler. |
| 1051 | */ |
| 1052 | static int run_pipe_real(struct pipe *pi) |
| 1053 | { |
| 1054 | int i; |
| 1055 | int nextin, nextout; |
| 1056 | int pipefds[2]; /* pipefds[0] is for reading */ |
| 1057 | struct child_prog *child; |
| 1058 | struct built_in_command *x; |
| 1059 | |
| 1060 | nextin = 0; |
| 1061 | pi->pgrp = 0; |
| 1062 | |
| 1063 | /* Check if this is a simple builtin (not part of a pipe). |
| 1064 | * Builtins within pipes have to fork anyway, and are handled in |
| 1065 | * pseudo_exec. "echo foo | read bar" doesn't work on bash, either. |
| 1066 | */ |
| 1067 | if (pi->num_progs == 1 && pi->progs[0].argv != NULL) { |
| 1068 | child = & (pi->progs[0]); |
| 1069 | if (child->group && ! child->subshell) { |
| 1070 | int squirrel[] = {-1, -1, -1}; |
| 1071 | int rcode; |
| 1072 | debug_printf("non-subshell grouping\n"); |
| 1073 | setup_redirects(child, squirrel); |
| 1074 | /* XXX could we merge code with following builtin case, |
| 1075 | * by creating a pseudo builtin that calls run_list_real? */ |
| 1076 | rcode = run_list_real(child->group); |
| 1077 | restore_redirects(squirrel); |
| 1078 | return rcode; |
| 1079 | } |
| 1080 | for (x = bltins; x->cmd; x++) { |
| 1081 | if (strcmp(child->argv[0], x->cmd) == 0 ) { |
| 1082 | int squirrel[] = {-1, -1, -1}; |
| 1083 | int rcode; |
| 1084 | debug_printf("builtin inline %s\n", child->argv[0]); |
| 1085 | /* XXX setup_redirects acts on file descriptors, not FILEs. |
| 1086 | * This is perfect for work that comes after exec(). |
| 1087 | * Is it really safe for inline use? Experimentally, |
| 1088 | * things seem to work with glibc. */ |
| 1089 | setup_redirects(child, squirrel); |
| 1090 | rcode = x->function(child); |
| 1091 | restore_redirects(squirrel); |
| 1092 | return rcode; |
| 1093 | } |
| 1094 | } |
| 1095 | } |
| 1096 | |
| 1097 | for (i = 0; i < pi->num_progs; i++) { |
| 1098 | child = & (pi->progs[i]); |
| 1099 | |
| 1100 | /* pipes are inserted between pairs of commands */ |
| 1101 | if ((i + 1) < pi->num_progs) { |
| 1102 | if (pipe(pipefds)<0) perror_msg_and_die("pipe"); |
| 1103 | nextout = pipefds[1]; |
| 1104 | } else { |
| 1105 | nextout=1; |
| 1106 | pipefds[0] = -1; |
| 1107 | } |
| 1108 | |
| 1109 | /* XXX test for failed fork()? */ |
| 1110 | if (!(child->pid = fork())) { |
| 1111 | close_all(); |
| 1112 | |
| 1113 | if (nextin != 0) { |
| 1114 | dup2(nextin, 0); |
| 1115 | close(nextin); |
| 1116 | } |
| 1117 | if (nextout != 1) { |
| 1118 | dup2(nextout, 1); |
| 1119 | close(nextout); |
| 1120 | } |
| 1121 | if (pipefds[0]!=-1) { |
| 1122 | close(pipefds[0]); /* opposite end of our output pipe */ |
| 1123 | } |
| 1124 | |
| 1125 | /* Like bash, explicit redirects override pipes, |
| 1126 | * and the pipe fd is available for dup'ing. */ |
| 1127 | setup_redirects(child,NULL); |
| 1128 | |
| 1129 | pseudo_exec(child); |
| 1130 | } |
| 1131 | if (interactive) { |
| 1132 | /* Put our child in the process group whose leader is the |
| 1133 | * first process in this pipe. */ |
| 1134 | if (pi->pgrp==0) { |
| 1135 | pi->pgrp = child->pid; |
| 1136 | } |
| 1137 | /* Don't check for errors. The child may be dead already, |
| 1138 | * in which case setpgid returns error code EACCES. */ |
| 1139 | setpgid(child->pid, pi->pgrp); |
| 1140 | } |
| 1141 | /* In the non-interactive case, do nothing. Leave the children |
| 1142 | * with the process group that they inherited from us. */ |
| 1143 | |
| 1144 | if (nextin != 0) |
| 1145 | close(nextin); |
| 1146 | if (nextout != 1) |
| 1147 | close(nextout); |
| 1148 | |
| 1149 | /* If there isn't another process, nextin is garbage |
| 1150 | but it doesn't matter */ |
| 1151 | nextin = pipefds[0]; |
| 1152 | } |
| 1153 | return -1; |
| 1154 | } |
| 1155 | |
| 1156 | static int run_list_real(struct pipe *pi) |
| 1157 | { |
| 1158 | int rcode=0; |
| 1159 | int if_code=0, next_if_code=0; /* need double-buffer to handle elif */ |
Eric Andersen | 4ed5e37 | 2001-05-01 01:49:50 +0000 | [diff] [blame^] | 1160 | reserved_style rmode, skip_more_in_this_rmode=RES_XXXX; |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 1161 | for (;pi;pi=pi->next) { |
| 1162 | rmode = pi->r_mode; |
Eric Andersen | 4ed5e37 | 2001-05-01 01:49:50 +0000 | [diff] [blame^] | 1163 | 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); |
| 1164 | if (rmode == skip_more_in_this_rmode) continue; |
| 1165 | skip_more_in_this_rmode = RES_XXXX; |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 1166 | if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code; |
| 1167 | if (rmode == RES_THEN && if_code) continue; |
| 1168 | if (rmode == RES_ELSE && !if_code) continue; |
| 1169 | if (rmode == RES_ELIF && !if_code) continue; |
Eric Andersen | 4ed5e37 | 2001-05-01 01:49:50 +0000 | [diff] [blame^] | 1170 | if (pi->num_progs == 0) continue; |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 1171 | rcode = run_pipe_real(pi); |
| 1172 | if (rcode!=-1) { |
| 1173 | /* We only ran a builtin: rcode was set by the return value |
| 1174 | * of run_pipe_real(), and we don't need to wait for anything. */ |
| 1175 | } else if (pi->followup==PIPE_BG) { |
| 1176 | /* XXX check bash's behavior with nontrivial pipes */ |
| 1177 | /* XXX compute jobid */ |
| 1178 | /* XXX what does bash do with attempts to background builtins? */ |
| 1179 | printf("[%d] %d\n", pi->jobid, pi->pgrp); |
| 1180 | last_bg_pid = pi->pgrp; |
| 1181 | rcode = EXIT_SUCCESS; |
| 1182 | } else { |
| 1183 | if (interactive) { |
| 1184 | /* move the new process group into the foreground */ |
| 1185 | /* suppress messages when run from /linuxrc mag@sysgo.de */ |
| 1186 | signal(SIGTTIN, SIG_IGN); |
| 1187 | signal(SIGTTOU, SIG_IGN); |
| 1188 | if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY) |
| 1189 | perror_msg("tcsetpgrp"); |
| 1190 | rcode = pipe_wait(pi); |
| 1191 | if (tcsetpgrp(0, getpid()) && errno != ENOTTY) |
| 1192 | perror_msg("tcsetpgrp"); |
| 1193 | signal(SIGTTIN, SIG_DFL); |
| 1194 | signal(SIGTTOU, SIG_DFL); |
| 1195 | } else { |
| 1196 | rcode = pipe_wait(pi); |
| 1197 | } |
| 1198 | } |
| 1199 | last_return_code=rcode; |
| 1200 | if ( rmode == RES_IF || rmode == RES_ELIF ) |
| 1201 | next_if_code=rcode; /* can be overwritten a number of times */ |
| 1202 | if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) || |
| 1203 | (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) ) |
Eric Andersen | 4ed5e37 | 2001-05-01 01:49:50 +0000 | [diff] [blame^] | 1204 | skip_more_in_this_rmode=rmode; |
| 1205 | /* return rcode; */ /* XXX broken if list is part of if/then/else */ |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 1206 | } |
| 1207 | return rcode; |
| 1208 | } |
| 1209 | |
| 1210 | /* broken, of course, but OK for testing */ |
| 1211 | static char *indenter(int i) |
| 1212 | { |
| 1213 | static char blanks[]=" "; |
| 1214 | return &blanks[sizeof(blanks)-i-1]; |
| 1215 | } |
| 1216 | |
| 1217 | /* return code is the exit status of the pipe */ |
| 1218 | static int run_pipe_test(struct pipe *pi, int indent) |
| 1219 | { |
| 1220 | char **p; |
| 1221 | struct child_prog *child; |
| 1222 | struct redir_struct *r, *rnext; |
| 1223 | int a, i, ret_code=0; |
| 1224 | char *ind = indenter(indent); |
| 1225 | final_printf("%s run pipe: (pid %d)\n",ind,getpid()); |
| 1226 | for (i=0; i<pi->num_progs; i++) { |
| 1227 | child = &pi->progs[i]; |
| 1228 | final_printf("%s command %d:\n",ind,i); |
| 1229 | if (child->argv) { |
| 1230 | for (a=0,p=child->argv; *p; a++,p++) { |
| 1231 | final_printf("%s argv[%d] = %s\n",ind,a,*p); |
| 1232 | } |
| 1233 | globfree(&child->glob_result); |
| 1234 | child->argv=NULL; |
| 1235 | } else if (child->group) { |
| 1236 | final_printf("%s begin group (subshell:%d)\n",ind, child->subshell); |
| 1237 | ret_code = run_list_test(child->group,indent+3); |
| 1238 | final_printf("%s end group\n",ind); |
| 1239 | } else { |
| 1240 | final_printf("%s (nil)\n",ind); |
| 1241 | } |
| 1242 | for (r=child->redirects; r; r=rnext) { |
| 1243 | final_printf("%s redirect %d%s", ind, r->fd, redir_table[r->type].descrip); |
| 1244 | if (r->dup == -1) { |
| 1245 | final_printf(" %s\n", *r->word.gl_pathv); |
| 1246 | globfree(&r->word); |
| 1247 | } else { |
| 1248 | final_printf("&%d\n", r->dup); |
| 1249 | } |
| 1250 | rnext=r->next; |
| 1251 | free(r); |
| 1252 | } |
| 1253 | child->redirects=NULL; |
| 1254 | } |
| 1255 | free(pi->progs); /* children are an array, they get freed all at once */ |
| 1256 | pi->progs=NULL; |
| 1257 | return ret_code; |
| 1258 | } |
| 1259 | |
| 1260 | static int run_list_test(struct pipe *head, int indent) |
| 1261 | { |
| 1262 | int rcode=0; /* if list has no members */ |
| 1263 | struct pipe *pi, *next; |
| 1264 | char *ind = indenter(indent); |
| 1265 | for (pi=head; pi; pi=next) { |
| 1266 | if (pi->num_progs == 0) break; |
| 1267 | final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode); |
| 1268 | rcode = run_pipe_test(pi, indent); |
| 1269 | final_printf("%s pipe followup code %d\n", ind, pi->followup); |
| 1270 | next=pi->next; |
| 1271 | pi->next=NULL; |
| 1272 | free(pi); |
| 1273 | } |
| 1274 | return rcode; |
| 1275 | } |
| 1276 | |
| 1277 | /* Select which version we will use */ |
| 1278 | static int run_list(struct pipe *pi) |
| 1279 | { |
| 1280 | int rcode=0; |
| 1281 | if (fake_mode==0) { |
| 1282 | rcode = run_list_real(pi); |
| 1283 | } |
| 1284 | /* run_list_test has the side effect of clearing memory |
| 1285 | * In the long run that function can be merged with run_list_real, |
| 1286 | * but doing that now would hobble the debugging effort. */ |
| 1287 | run_list_test(pi,0); |
| 1288 | return rcode; |
| 1289 | } |
| 1290 | |
| 1291 | /* The API for glob is arguably broken. This routine pushes a non-matching |
| 1292 | * string into the output structure, removing non-backslashed backslashes. |
| 1293 | * If someone can prove me wrong, by performing this function within the |
| 1294 | * original glob(3) api, feel free to rewrite this routine into oblivion. |
| 1295 | * Return code (0 vs. GLOB_NOSPACE) matches glob(3). |
| 1296 | * XXX broken if the last character is '\\', check that before calling. |
| 1297 | */ |
| 1298 | static int globhack(const char *src, int flags, glob_t *pglob) |
| 1299 | { |
| 1300 | int cnt, pathc; |
| 1301 | const char *s; |
| 1302 | char *dest; |
| 1303 | for (cnt=1, s=src; *s; s++) { |
| 1304 | if (*s == '\\') s++; |
| 1305 | cnt++; |
| 1306 | } |
| 1307 | dest = malloc(cnt); |
| 1308 | if (!dest) return GLOB_NOSPACE; |
| 1309 | if (!(flags & GLOB_APPEND)) { |
| 1310 | pglob->gl_pathv=NULL; |
| 1311 | pglob->gl_pathc=0; |
| 1312 | pglob->gl_offs=0; |
| 1313 | pglob->gl_offs=0; |
| 1314 | } |
| 1315 | pathc = ++pglob->gl_pathc; |
| 1316 | pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv)); |
| 1317 | if (pglob->gl_pathv == NULL) return GLOB_NOSPACE; |
| 1318 | pglob->gl_pathv[pathc-1]=dest; |
| 1319 | pglob->gl_pathv[pathc]=NULL; |
| 1320 | for (s=src; *s; s++, dest++) { |
| 1321 | if (*s == '\\') s++; |
| 1322 | *dest = *s; |
| 1323 | } |
| 1324 | *dest='\0'; |
| 1325 | return 0; |
| 1326 | } |
| 1327 | |
| 1328 | /* XXX broken if the last character is '\\', check that before calling */ |
| 1329 | static int glob_needed(const char *s) |
| 1330 | { |
| 1331 | for (; *s; s++) { |
| 1332 | if (*s == '\\') s++; |
| 1333 | if (strchr("*[?",*s)) return 1; |
| 1334 | } |
| 1335 | return 0; |
| 1336 | } |
| 1337 | |
| 1338 | #if 0 |
| 1339 | static void globprint(glob_t *pglob) |
| 1340 | { |
| 1341 | int i; |
| 1342 | debug_printf("glob_t at %p:\n", pglob); |
| 1343 | debug_printf(" gl_pathc=%d gl_pathv=%p gl_offs=%d gl_flags=%d\n", |
| 1344 | pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags); |
| 1345 | for (i=0; i<pglob->gl_pathc; i++) |
| 1346 | debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i, |
| 1347 | pglob->gl_pathv[i], pglob->gl_pathv[i]); |
| 1348 | } |
| 1349 | #endif |
| 1350 | |
| 1351 | static int xglob(o_string *dest, int flags, glob_t *pglob) |
| 1352 | { |
| 1353 | int gr; |
| 1354 | |
| 1355 | /* short-circuit for null word */ |
| 1356 | /* we can code this better when the debug_printf's are gone */ |
| 1357 | if (dest->length == 0) { |
| 1358 | if (dest->nonnull) { |
| 1359 | /* bash man page calls this an "explicit" null */ |
| 1360 | gr = globhack(dest->data, flags, pglob); |
| 1361 | debug_printf("globhack returned %d\n",gr); |
| 1362 | } else { |
| 1363 | return 0; |
| 1364 | } |
| 1365 | } else if (glob_needed(dest->data)) { |
| 1366 | gr = glob(dest->data, flags, NULL, pglob); |
| 1367 | debug_printf("glob returned %d\n",gr); |
| 1368 | if (gr == GLOB_NOMATCH) { |
| 1369 | /* quote removal, or more accurately, backslash removal */ |
| 1370 | gr = globhack(dest->data, flags, pglob); |
| 1371 | debug_printf("globhack returned %d\n",gr); |
| 1372 | } |
| 1373 | } else { |
| 1374 | gr = globhack(dest->data, flags, pglob); |
| 1375 | debug_printf("globhack returned %d\n",gr); |
| 1376 | } |
| 1377 | if (gr == GLOB_NOSPACE) { |
| 1378 | fprintf(stderr,"out of memory during glob\n"); |
| 1379 | exit(1); |
| 1380 | } |
| 1381 | if (gr != 0) { /* GLOB_ABORTED ? */ |
| 1382 | fprintf(stderr,"glob(3) error %d\n",gr); |
| 1383 | } |
| 1384 | /* globprint(glob_target); */ |
| 1385 | return gr; |
| 1386 | } |
| 1387 | |
| 1388 | /* the src parameter allows us to peek forward to a possible &n syntax |
| 1389 | * for file descriptor duplication, e.g., "2>&1". |
| 1390 | * Return code is 0 normally, 1 if a syntax error is detected in src. |
| 1391 | * Resource errors (in xmalloc) cause the process to exit */ |
| 1392 | static int setup_redirect(struct p_context *ctx, int fd, redir_type style, |
| 1393 | struct in_str *input) |
| 1394 | { |
| 1395 | struct child_prog *child=ctx->child; |
| 1396 | struct redir_struct *redir = child->redirects; |
| 1397 | struct redir_struct *last_redir=NULL; |
| 1398 | |
| 1399 | /* Create a new redir_struct and drop it onto the end of the linked list */ |
| 1400 | while(redir) { |
| 1401 | last_redir=redir; |
| 1402 | redir=redir->next; |
| 1403 | } |
| 1404 | redir = xmalloc(sizeof(struct redir_struct)); |
| 1405 | redir->next=NULL; |
| 1406 | if (last_redir) { |
| 1407 | last_redir->next=redir; |
| 1408 | } else { |
| 1409 | child->redirects=redir; |
| 1410 | } |
| 1411 | |
| 1412 | redir->type=style; |
| 1413 | redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ; |
| 1414 | |
| 1415 | debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip); |
| 1416 | |
| 1417 | /* Check for a '2>&1' type redirect */ |
| 1418 | redir->dup = redirect_dup_num(input); |
| 1419 | if (redir->dup == -2) return 1; /* syntax error */ |
| 1420 | if (redir->dup != -1) { |
| 1421 | /* Erik had a check here that the file descriptor in question |
| 1422 | * is legit; I postpone that to "run time" */ |
| 1423 | debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup); |
| 1424 | } else { |
| 1425 | /* We do _not_ try to open the file that src points to, |
| 1426 | * since we need to return and let src be expanded first. |
| 1427 | * Set ctx->pending_redirect, so we know what to do at the |
| 1428 | * end of the next parsed word. |
| 1429 | */ |
| 1430 | ctx->pending_redirect = redir; |
| 1431 | } |
| 1432 | return 0; |
| 1433 | } |
| 1434 | |
| 1435 | struct pipe *new_pipe(void) { |
| 1436 | struct pipe *pi; |
| 1437 | pi = xmalloc(sizeof(struct pipe)); |
| 1438 | pi->num_progs = 0; |
| 1439 | pi->progs = NULL; |
| 1440 | pi->next = NULL; |
| 1441 | pi->followup = 0; /* invalid */ |
| 1442 | return pi; |
| 1443 | } |
| 1444 | |
| 1445 | static void initialize_context(struct p_context *ctx) |
| 1446 | { |
| 1447 | ctx->pipe=NULL; |
| 1448 | ctx->pending_redirect=NULL; |
| 1449 | ctx->child=NULL; |
| 1450 | ctx->list_head=new_pipe(); |
| 1451 | ctx->pipe=ctx->list_head; |
| 1452 | ctx->w=RES_NONE; |
| 1453 | ctx->stack=NULL; |
| 1454 | done_command(ctx); /* creates the memory for working child */ |
| 1455 | } |
| 1456 | |
| 1457 | /* normal return is 0 |
| 1458 | * if a reserved word is found, and processed, return 1 |
| 1459 | * should handle if, then, elif, else, fi, for, while, until, do, done. |
| 1460 | * case, function, and select are obnoxious, save those for later. |
| 1461 | */ |
| 1462 | int reserved_word(o_string *dest, struct p_context *ctx) |
| 1463 | { |
| 1464 | struct reserved_combo { |
| 1465 | char *literal; |
| 1466 | int code; |
| 1467 | long flag; |
| 1468 | }; |
| 1469 | /* Mostly a list of accepted follow-up reserved words. |
| 1470 | * FLAG_END means we are done with the sequence, and are ready |
| 1471 | * to turn the compound list into a command. |
| 1472 | * FLAG_START means the word must start a new compound list. |
| 1473 | */ |
| 1474 | static struct reserved_combo reserved_list[] = { |
| 1475 | { "if", RES_IF, FLAG_THEN | FLAG_START }, |
| 1476 | { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI }, |
| 1477 | { "elif", RES_ELIF, FLAG_THEN }, |
| 1478 | { "else", RES_ELSE, FLAG_FI }, |
| 1479 | { "fi", RES_FI, FLAG_END }, |
| 1480 | { "for", RES_FOR, FLAG_DO | FLAG_START }, |
| 1481 | { "while", RES_WHILE, FLAG_DO | FLAG_START }, |
| 1482 | { "until", RES_UNTIL, FLAG_DO | FLAG_START }, |
| 1483 | { "do", RES_DO, FLAG_DONE }, |
| 1484 | { "done", RES_DONE, FLAG_END } |
| 1485 | }; |
| 1486 | struct reserved_combo *r; |
| 1487 | for (r=reserved_list; |
| 1488 | #define NRES sizeof(reserved_list)/sizeof(struct reserved_combo) |
| 1489 | r<reserved_list+NRES; r++) { |
| 1490 | if (strcmp(dest->data, r->literal) == 0) { |
| 1491 | debug_printf("found reserved word %s, code %d\n",r->literal,r->code); |
| 1492 | if (r->flag & FLAG_START) { |
| 1493 | struct p_context *new = xmalloc(sizeof(struct p_context)); |
| 1494 | debug_printf("push stack\n"); |
| 1495 | *new = *ctx; /* physical copy */ |
| 1496 | initialize_context(ctx); |
| 1497 | ctx->stack=new; |
| 1498 | } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) { |
Eric Andersen | af44a0e | 2001-04-27 07:26:12 +0000 | [diff] [blame] | 1499 | syntax(); |
| 1500 | ctx->w = RES_SNTX; |
| 1501 | b_reset (dest); |
| 1502 | return 1; |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 1503 | } |
| 1504 | ctx->w=r->code; |
| 1505 | ctx->old_flag = r->flag; |
| 1506 | if (ctx->old_flag & FLAG_END) { |
| 1507 | struct p_context *old; |
| 1508 | debug_printf("pop stack\n"); |
| 1509 | old = ctx->stack; |
| 1510 | old->child->group = ctx->list_head; |
| 1511 | *ctx = *old; /* physical copy */ |
| 1512 | free(old); |
| 1513 | ctx->w=RES_NONE; |
| 1514 | } |
| 1515 | b_reset (dest); |
| 1516 | return 1; |
| 1517 | } |
| 1518 | } |
| 1519 | return 0; |
| 1520 | } |
| 1521 | |
| 1522 | /* normal return is 0. |
| 1523 | * Syntax or xglob errors return 1. */ |
| 1524 | static int done_word(o_string *dest, struct p_context *ctx) |
| 1525 | { |
| 1526 | struct child_prog *child=ctx->child; |
| 1527 | glob_t *glob_target; |
| 1528 | int gr, flags = 0; |
| 1529 | |
| 1530 | debug_printf("done_word: %s %p\n", dest->data, child); |
| 1531 | if (dest->length == 0 && !dest->nonnull) { |
| 1532 | debug_printf(" true null, ignored\n"); |
| 1533 | return 0; |
| 1534 | } |
| 1535 | if (ctx->pending_redirect) { |
| 1536 | glob_target = &ctx->pending_redirect->word; |
| 1537 | } else { |
| 1538 | if (child->group) { |
| 1539 | syntax(); |
| 1540 | return 1; /* syntax error, groups and arglists don't mix */ |
| 1541 | } |
| 1542 | if (!child->argv) { |
| 1543 | debug_printf("checking %s for reserved-ness\n",dest->data); |
Eric Andersen | af44a0e | 2001-04-27 07:26:12 +0000 | [diff] [blame] | 1544 | if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX; |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 1545 | } |
| 1546 | glob_target = &child->glob_result; |
| 1547 | if (child->argv) flags |= GLOB_APPEND; |
| 1548 | } |
| 1549 | gr = xglob(dest, flags, glob_target); |
| 1550 | if (gr != 0) return 1; |
| 1551 | |
| 1552 | b_reset(dest); |
| 1553 | if (ctx->pending_redirect) { |
| 1554 | ctx->pending_redirect=NULL; |
| 1555 | if (glob_target->gl_pathc != 1) { |
| 1556 | fprintf(stderr, "ambiguous redirect\n"); |
| 1557 | return 1; |
| 1558 | } |
| 1559 | } else { |
| 1560 | child->argv = glob_target->gl_pathv; |
| 1561 | } |
| 1562 | return 0; |
| 1563 | } |
| 1564 | |
| 1565 | /* The only possible error here is out of memory, in which case |
| 1566 | * xmalloc exits. */ |
| 1567 | static int done_command(struct p_context *ctx) |
| 1568 | { |
| 1569 | /* The child is really already in the pipe structure, so |
| 1570 | * advance the pipe counter and make a new, null child. |
| 1571 | * Only real trickiness here is that the uncommitted |
| 1572 | * child structure, to which ctx->child points, is not |
| 1573 | * counted in pi->num_progs. */ |
| 1574 | struct pipe *pi=ctx->pipe; |
| 1575 | struct child_prog *prog=ctx->child; |
| 1576 | |
| 1577 | if (prog && prog->group == NULL |
| 1578 | && prog->argv == NULL |
| 1579 | && prog->redirects == NULL) { |
| 1580 | debug_printf("done_command: skipping null command\n"); |
| 1581 | return 0; |
| 1582 | } else if (prog) { |
| 1583 | pi->num_progs++; |
| 1584 | debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs); |
| 1585 | } else { |
| 1586 | debug_printf("done_command: initializing\n"); |
| 1587 | } |
| 1588 | pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1)); |
| 1589 | |
| 1590 | prog = pi->progs + pi->num_progs; |
| 1591 | prog->redirects = NULL; |
| 1592 | prog->argv = NULL; |
| 1593 | prog->is_stopped = 0; |
| 1594 | prog->group = NULL; |
| 1595 | prog->glob_result.gl_pathv = NULL; |
| 1596 | prog->family = pi; |
| 1597 | |
| 1598 | ctx->child=prog; |
| 1599 | /* but ctx->pipe and ctx->list_head remain unchanged */ |
| 1600 | return 0; |
| 1601 | } |
| 1602 | |
| 1603 | static int done_pipe(struct p_context *ctx, pipe_style type) |
| 1604 | { |
| 1605 | struct pipe *new_p; |
| 1606 | done_command(ctx); /* implicit closure of previous command */ |
| 1607 | debug_printf("done_pipe, type %d\n", type); |
| 1608 | ctx->pipe->followup = type; |
| 1609 | ctx->pipe->r_mode = ctx->w; |
| 1610 | new_p=new_pipe(); |
| 1611 | ctx->pipe->next = new_p; |
| 1612 | ctx->pipe = new_p; |
| 1613 | ctx->child = NULL; |
| 1614 | done_command(ctx); /* set up new pipe to accept commands */ |
| 1615 | return 0; |
| 1616 | } |
| 1617 | |
| 1618 | /* peek ahead in the in_str to find out if we have a "&n" construct, |
| 1619 | * as in "2>&1", that represents duplicating a file descriptor. |
| 1620 | * returns either -2 (syntax error), -1 (no &), or the number found. |
| 1621 | */ |
| 1622 | static int redirect_dup_num(struct in_str *input) |
| 1623 | { |
| 1624 | int ch, d=0, ok=0; |
| 1625 | ch = b_peek(input); |
| 1626 | if (ch != '&') return -1; |
| 1627 | |
| 1628 | b_getch(input); /* get the & */ |
| 1629 | while (ch=b_peek(input),isdigit(ch)) { |
| 1630 | d = d*10+(ch-'0'); |
| 1631 | ok=1; |
| 1632 | b_getch(input); |
| 1633 | } |
| 1634 | if (ok) return d; |
| 1635 | |
| 1636 | fprintf(stderr, "ambiguous redirect\n"); |
| 1637 | return -2; |
| 1638 | } |
| 1639 | |
| 1640 | /* If a redirect is immediately preceded by a number, that number is |
| 1641 | * supposed to tell which file descriptor to redirect. This routine |
| 1642 | * looks for such preceding numbers. In an ideal world this routine |
| 1643 | * needs to handle all the following classes of redirects... |
| 1644 | * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo |
| 1645 | * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo |
| 1646 | * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo |
| 1647 | * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo |
| 1648 | * A -1 output from this program means no valid number was found, so the |
| 1649 | * caller should use the appropriate default for this redirection. |
| 1650 | */ |
| 1651 | static int redirect_opt_num(o_string *o) |
| 1652 | { |
| 1653 | int num; |
| 1654 | |
| 1655 | if (o->length==0) return -1; |
| 1656 | for(num=0; num<o->length; num++) { |
| 1657 | if (!isdigit(*(o->data+num))) { |
| 1658 | return -1; |
| 1659 | } |
| 1660 | } |
| 1661 | /* reuse num (and save an int) */ |
| 1662 | num=atoi(o->data); |
| 1663 | b_reset(o); |
| 1664 | return num; |
| 1665 | } |
| 1666 | |
| 1667 | FILE *generate_stream_from_list(struct pipe *head) |
| 1668 | { |
| 1669 | FILE *pf; |
| 1670 | #if 1 |
| 1671 | int pid, channel[2]; |
| 1672 | if (pipe(channel)<0) perror_msg_and_die("pipe"); |
| 1673 | pid=fork(); |
| 1674 | if (pid<0) { |
| 1675 | perror_msg_and_die("fork"); |
| 1676 | } else if (pid==0) { |
| 1677 | close(channel[0]); |
| 1678 | if (channel[1] != 1) { |
| 1679 | dup2(channel[1],1); |
| 1680 | close(channel[1]); |
| 1681 | } |
| 1682 | #if 0 |
| 1683 | #define SURROGATE "surrogate response" |
| 1684 | write(1,SURROGATE,sizeof(SURROGATE)); |
| 1685 | exit(run_list(head)); |
| 1686 | #else |
| 1687 | exit(run_list_real(head)); /* leaks memory */ |
| 1688 | #endif |
| 1689 | } |
| 1690 | debug_printf("forked child %d\n",pid); |
| 1691 | close(channel[1]); |
| 1692 | pf = fdopen(channel[0],"r"); |
| 1693 | debug_printf("pipe on FILE *%p\n",pf); |
| 1694 | #else |
| 1695 | run_list_test(head,0); |
| 1696 | pf=popen("echo surrogate response","r"); |
| 1697 | debug_printf("started fake pipe on FILE *%p\n",pf); |
| 1698 | #endif |
| 1699 | return pf; |
| 1700 | } |
| 1701 | |
| 1702 | /* this version hacked for testing purposes */ |
| 1703 | /* return code is exit status of the process that is run. */ |
| 1704 | static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end) |
| 1705 | { |
| 1706 | int retcode; |
| 1707 | o_string result=NULL_O_STRING; |
| 1708 | struct p_context inner; |
| 1709 | FILE *p; |
| 1710 | struct in_str pipe_str; |
| 1711 | initialize_context(&inner); |
| 1712 | |
| 1713 | /* recursion to generate command */ |
| 1714 | retcode = parse_stream(&result, &inner, input, subst_end); |
| 1715 | if (retcode != 0) return retcode; /* syntax error or EOF */ |
| 1716 | done_word(&result, &inner); |
| 1717 | done_pipe(&inner, PIPE_SEQ); |
| 1718 | b_free(&result); |
| 1719 | |
| 1720 | p=generate_stream_from_list(inner.list_head); |
| 1721 | if (p==NULL) return 1; |
| 1722 | mark_open(fileno(p)); |
| 1723 | setup_file_in_str(&pipe_str, p); |
| 1724 | |
| 1725 | /* now send results of command back into original context */ |
| 1726 | retcode = parse_stream(dest, ctx, &pipe_str, '\0'); |
| 1727 | /* XXX In case of a syntax error, should we try to kill the child? |
| 1728 | * That would be tough to do right, so just read until EOF. */ |
| 1729 | if (retcode == 1) { |
| 1730 | while (b_getch(&pipe_str)!=EOF) { /* discard */ }; |
| 1731 | } |
| 1732 | |
| 1733 | debug_printf("done reading from pipe, pclose()ing\n"); |
| 1734 | /* This is the step that wait()s for the child. Should be pretty |
| 1735 | * safe, since we just read an EOF from its stdout. We could try |
| 1736 | * to better, by using wait(), and keeping track of background jobs |
| 1737 | * at the same time. That would be a lot of work, and contrary |
| 1738 | * to the KISS philosophy of this program. */ |
| 1739 | mark_closed(fileno(p)); |
| 1740 | retcode=pclose(p); |
| 1741 | debug_printf("pclosed, retcode=%d\n",retcode); |
| 1742 | /* XXX this process fails to trim a single trailing newline */ |
| 1743 | return retcode; |
| 1744 | } |
| 1745 | |
| 1746 | static int parse_group(o_string *dest, struct p_context *ctx, |
| 1747 | struct in_str *input, int ch) |
| 1748 | { |
| 1749 | int rcode, endch=0; |
| 1750 | struct p_context sub; |
| 1751 | struct child_prog *child = ctx->child; |
| 1752 | if (child->argv) { |
| 1753 | syntax(); |
| 1754 | return 1; /* syntax error, groups and arglists don't mix */ |
| 1755 | } |
| 1756 | initialize_context(&sub); |
| 1757 | switch(ch) { |
| 1758 | case '(': endch=')'; child->subshell=1; break; |
| 1759 | case '{': endch='}'; break; |
| 1760 | default: syntax(); /* really logic error */ |
| 1761 | } |
| 1762 | rcode=parse_stream(dest,&sub,input,endch); |
| 1763 | done_word(dest,&sub); /* finish off the final word in the subcontext */ |
| 1764 | done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */ |
| 1765 | child->group = sub.list_head; |
| 1766 | return rcode; |
| 1767 | /* child remains "open", available for possible redirects */ |
| 1768 | } |
| 1769 | |
| 1770 | /* basically useful version until someone wants to get fancier, |
| 1771 | * see the bash man page under "Parameter Expansion" */ |
| 1772 | static void lookup_param(o_string *dest, struct p_context *ctx, o_string *src) |
| 1773 | { |
| 1774 | const char *p=NULL; |
| 1775 | if (src->data) p = getenv(src->data); |
| 1776 | if (p) parse_string(dest, ctx, p); /* recursion */ |
| 1777 | b_free(src); |
| 1778 | } |
| 1779 | |
| 1780 | /* return code: 0 for OK, 1 for syntax error */ |
| 1781 | static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input) |
| 1782 | { |
| 1783 | int i, advance=0; |
| 1784 | o_string alt=NULL_O_STRING; |
| 1785 | char sep[]=" "; |
| 1786 | int ch = input->peek(input); /* first character after the $ */ |
| 1787 | debug_printf("handle_dollar: ch=%c\n",ch); |
| 1788 | if (isalpha(ch)) { |
| 1789 | while(ch=b_peek(input),isalnum(ch) || ch=='_') { |
| 1790 | b_getch(input); |
| 1791 | b_addchr(&alt,ch); |
| 1792 | } |
| 1793 | lookup_param(dest, ctx, &alt); |
| 1794 | } else if (isdigit(ch)) { |
| 1795 | i = ch-'0'; /* XXX is $0 special? */ |
| 1796 | if (i<global_argc) { |
| 1797 | parse_string(dest, ctx, global_argv[i]); /* recursion */ |
| 1798 | } |
| 1799 | advance = 1; |
| 1800 | } else switch (ch) { |
| 1801 | case '$': |
| 1802 | b_adduint(dest,getpid()); |
| 1803 | advance = 1; |
| 1804 | break; |
| 1805 | case '!': |
| 1806 | if (last_bg_pid > 0) b_adduint(dest, last_bg_pid); |
| 1807 | advance = 1; |
| 1808 | break; |
| 1809 | case '?': |
| 1810 | b_adduint(dest,last_return_code); |
| 1811 | advance = 1; |
| 1812 | break; |
| 1813 | case '#': |
| 1814 | b_adduint(dest,global_argc ? global_argc-1 : 0); |
| 1815 | advance = 1; |
| 1816 | break; |
| 1817 | case '{': |
| 1818 | b_getch(input); |
| 1819 | /* XXX maybe someone will try to escape the '}' */ |
| 1820 | while(ch=b_getch(input),ch!=EOF && ch!='}') { |
| 1821 | b_addchr(&alt,ch); |
| 1822 | } |
| 1823 | if (ch != '}') { |
| 1824 | syntax(); |
| 1825 | return 1; |
| 1826 | } |
| 1827 | lookup_param(dest, ctx, &alt); |
| 1828 | break; |
| 1829 | case '(': |
| 1830 | process_command_subs(dest, ctx, input, ')'); |
| 1831 | break; |
| 1832 | case '*': |
| 1833 | sep[0]=ifs[0]; |
| 1834 | for (i=1; i<global_argc; i++) { |
| 1835 | parse_string(dest, ctx, global_argv[i]); |
| 1836 | if (i+1 < global_argc) parse_string(dest, ctx, sep); |
| 1837 | } |
| 1838 | break; |
| 1839 | case '@': |
| 1840 | case '-': |
| 1841 | case '_': |
| 1842 | /* still unhandled, but should be eventually */ |
| 1843 | fprintf(stderr,"unhandled syntax: $%c\n",ch); |
| 1844 | return 1; |
| 1845 | break; |
| 1846 | default: |
| 1847 | b_addqchr(dest,'$',dest->quote); |
| 1848 | } |
| 1849 | /* Eat the character if the flag was set. If the compiler |
| 1850 | * is smart enough, we could substitute "b_getch(input);" |
| 1851 | * for all the "advance = 1;" above, and also end up with |
| 1852 | * a nice size-optimized program. Hah! That'll be the day. |
| 1853 | */ |
| 1854 | if (advance) b_getch(input); |
| 1855 | return 0; |
| 1856 | } |
| 1857 | |
| 1858 | int parse_string(o_string *dest, struct p_context *ctx, const char *src) |
| 1859 | { |
| 1860 | struct in_str foo; |
| 1861 | setup_string_in_str(&foo, src); |
| 1862 | return parse_stream(dest, ctx, &foo, '\0'); |
| 1863 | } |
| 1864 | |
| 1865 | /* return code is 0 for normal exit, 1 for syntax error */ |
| 1866 | int parse_stream(o_string *dest, struct p_context *ctx, |
| 1867 | struct in_str *input, int end_trigger) |
| 1868 | { |
| 1869 | unsigned int ch, m; |
| 1870 | int redir_fd; |
| 1871 | redir_type redir_style; |
| 1872 | int next; |
| 1873 | |
| 1874 | /* Only double-quote state is handled in the state variable dest->quote. |
| 1875 | * A single-quote triggers a bypass of the main loop until its mate is |
| 1876 | * found. When recursing, quote state is passed in via dest->quote. */ |
| 1877 | |
| 1878 | debug_printf("parse_stream, end_trigger=%d\n",end_trigger); |
| 1879 | while ((ch=b_getch(input))!=EOF) { |
| 1880 | m = map[ch]; |
| 1881 | next = (ch == '\n') ? 0 : b_peek(input); |
| 1882 | debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d\n", |
| 1883 | ch,ch,m,dest->quote); |
| 1884 | if (m==0 || ((m==1 || m==2) && dest->quote)) { |
| 1885 | b_addqchr(dest, ch, dest->quote); |
Eric Andersen | aac75e5 | 2001-04-30 18:18:45 +0000 | [diff] [blame] | 1886 | } else { |
| 1887 | if (m==2) { /* unquoted IFS */ |
| 1888 | done_word(dest, ctx); |
| 1889 | if (ch=='\n') done_pipe(ctx,PIPE_SEQ); |
| 1890 | } |
Eric Andersen | af44a0e | 2001-04-27 07:26:12 +0000 | [diff] [blame] | 1891 | if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) { |
Eric Andersen | aac75e5 | 2001-04-30 18:18:45 +0000 | [diff] [blame] | 1892 | debug_printf("leaving parse_stream\n"); |
Eric Andersen | af44a0e | 2001-04-27 07:26:12 +0000 | [diff] [blame] | 1893 | return 0; |
| 1894 | } |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 1895 | #if 0 |
| 1896 | if (ch=='\n') { |
| 1897 | /* Yahoo! Time to run with it! */ |
| 1898 | done_pipe(ctx,PIPE_SEQ); |
| 1899 | run_list(ctx->list_head); |
| 1900 | initialize_context(ctx); |
| 1901 | } |
| 1902 | #endif |
Eric Andersen | aac75e5 | 2001-04-30 18:18:45 +0000 | [diff] [blame] | 1903 | if (m!=2) switch (ch) { |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 1904 | case '#': |
| 1905 | if (dest->length == 0 && !dest->quote) { |
| 1906 | while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); } |
| 1907 | } else { |
| 1908 | b_addqchr(dest, ch, dest->quote); |
| 1909 | } |
| 1910 | break; |
| 1911 | case '\\': |
| 1912 | if (next == EOF) { |
| 1913 | syntax(); |
| 1914 | return 1; |
| 1915 | } |
| 1916 | b_addqchr(dest, '\\', dest->quote); |
| 1917 | b_addqchr(dest, b_getch(input), dest->quote); |
| 1918 | break; |
| 1919 | case '$': |
| 1920 | if (handle_dollar(dest, ctx, input)!=0) return 1; |
| 1921 | break; |
| 1922 | case '\'': |
| 1923 | dest->nonnull = 1; |
| 1924 | while(ch=b_getch(input),ch!=EOF && ch!='\'') { |
| 1925 | b_addchr(dest,ch); |
| 1926 | } |
| 1927 | if (ch==EOF) { |
| 1928 | syntax(); |
| 1929 | return 1; |
| 1930 | } |
| 1931 | break; |
| 1932 | case '"': |
| 1933 | dest->nonnull = 1; |
| 1934 | dest->quote = !dest->quote; |
| 1935 | break; |
| 1936 | case '`': |
| 1937 | process_command_subs(dest, ctx, input, '`'); |
| 1938 | break; |
| 1939 | case '>': |
| 1940 | redir_fd = redirect_opt_num(dest); |
| 1941 | done_word(dest, ctx); |
| 1942 | redir_style=REDIRECT_OVERWRITE; |
| 1943 | if (next == '>') { |
| 1944 | redir_style=REDIRECT_APPEND; |
| 1945 | b_getch(input); |
| 1946 | } else if (next == '(') { |
| 1947 | syntax(); /* until we support >(list) Process Substitution */ |
| 1948 | return 1; |
| 1949 | } |
| 1950 | setup_redirect(ctx, redir_fd, redir_style, input); |
| 1951 | break; |
| 1952 | case '<': |
| 1953 | redir_fd = redirect_opt_num(dest); |
| 1954 | done_word(dest, ctx); |
| 1955 | redir_style=REDIRECT_INPUT; |
| 1956 | if (next == '<') { |
| 1957 | redir_style=REDIRECT_HEREIS; |
| 1958 | b_getch(input); |
| 1959 | } else if (next == '>') { |
| 1960 | redir_style=REDIRECT_IO; |
| 1961 | b_getch(input); |
| 1962 | } else if (next == '(') { |
| 1963 | syntax(); /* until we support <(list) Process Substitution */ |
| 1964 | return 1; |
| 1965 | } |
| 1966 | setup_redirect(ctx, redir_fd, redir_style, input); |
| 1967 | break; |
| 1968 | case ';': |
| 1969 | done_word(dest, ctx); |
| 1970 | done_pipe(ctx,PIPE_SEQ); |
| 1971 | break; |
| 1972 | case '&': |
| 1973 | done_word(dest, ctx); |
| 1974 | if (next=='&') { |
| 1975 | b_getch(input); |
| 1976 | done_pipe(ctx,PIPE_AND); |
| 1977 | } else { |
| 1978 | done_pipe(ctx,PIPE_BG); |
| 1979 | } |
| 1980 | break; |
| 1981 | case '|': |
| 1982 | done_word(dest, ctx); |
| 1983 | if (next=='|') { |
| 1984 | b_getch(input); |
| 1985 | done_pipe(ctx,PIPE_OR); |
| 1986 | } else { |
| 1987 | /* we could pick up a file descriptor choice here |
| 1988 | * with redirect_opt_num(), but bash doesn't do it. |
| 1989 | * "echo foo 2| cat" yields "foo 2". */ |
| 1990 | done_command(ctx); |
| 1991 | } |
| 1992 | break; |
| 1993 | case '(': |
| 1994 | case '{': |
| 1995 | if (parse_group(dest, ctx, input, ch)!=0) return 1; |
| 1996 | break; |
| 1997 | case ')': |
| 1998 | case '}': |
| 1999 | syntax(); /* Proper use of this character caught by end_trigger */ |
| 2000 | return 1; |
| 2001 | break; |
| 2002 | default: |
| 2003 | syntax(); /* this is really an internal logic error */ |
| 2004 | return 1; |
Eric Andersen | aac75e5 | 2001-04-30 18:18:45 +0000 | [diff] [blame] | 2005 | } |
Eric Andersen | 25f2703 | 2001-04-26 23:22:31 +0000 | [diff] [blame] | 2006 | } |
| 2007 | } |
| 2008 | /* complain if quote? No, maybe we just finished a command substitution |
| 2009 | * that was quoted. Example: |
| 2010 | * $ echo "`cat foo` plus more" |
| 2011 | * and we just got the EOF generated by the subshell that ran "cat foo" |
| 2012 | * The only real complaint is if we got an EOF when end_trigger != '\0', |
| 2013 | * that is, we were really supposed to get end_trigger, and never got |
| 2014 | * one before the EOF. Can't use the standard "syntax error" return code, |
| 2015 | * so that parse_stream_outer can distinguish the EOF and exit smoothly. */ |
| 2016 | if (end_trigger != '\0') return -1; |
| 2017 | return 0; |
| 2018 | } |
| 2019 | |
| 2020 | void mapset(const unsigned char *set, int code) |
| 2021 | { |
| 2022 | const unsigned char *s; |
| 2023 | for (s=set; *s; s++) map[*s] = code; |
| 2024 | } |
| 2025 | |
| 2026 | void update_ifs_map(void) |
| 2027 | { |
| 2028 | /* char *ifs and char map[256] are both globals. */ |
| 2029 | ifs = getenv("IFS"); |
| 2030 | if (ifs == NULL) ifs=" \t\n"; |
| 2031 | /* Precompute a list of 'flow through' behavior so it can be treated |
| 2032 | * quickly up front. Computation is necessary because of IFS. |
| 2033 | * Special case handling of IFS == " \t\n" is not implemented. |
| 2034 | * The map[] array only really needs two bits each, and on most machines |
| 2035 | * that would be faster because of the reduced L1 cache footprint. |
| 2036 | */ |
| 2037 | memset(map,0,256); /* most characters flow through always */ |
| 2038 | mapset("\\$'\"`", 3); /* never flow through */ |
| 2039 | mapset("<>;&|(){}#", 1); /* flow through if quoted */ |
| 2040 | mapset(ifs, 2); /* also flow through if quoted */ |
| 2041 | } |
| 2042 | |
| 2043 | /* most recursion does not come through here, the exeception is |
| 2044 | * from builtin_source() */ |
| 2045 | int parse_stream_outer(struct in_str *inp) |
| 2046 | { |
| 2047 | |
| 2048 | struct p_context ctx; |
| 2049 | o_string temp=NULL_O_STRING; |
| 2050 | int rcode; |
| 2051 | do { |
| 2052 | initialize_context(&ctx); |
| 2053 | update_ifs_map(); |
| 2054 | inp->promptmode=1; |
| 2055 | rcode = parse_stream(&temp, &ctx, inp, '\n'); |
| 2056 | done_word(&temp, &ctx); |
| 2057 | done_pipe(&ctx,PIPE_SEQ); |
| 2058 | run_list(ctx.list_head); |
| 2059 | } while (rcode != -1); /* loop on syntax errors, return on EOF */ |
| 2060 | return 0; |
| 2061 | } |
| 2062 | |
| 2063 | static int parse_string_outer(const char *s) |
| 2064 | { |
| 2065 | struct in_str input; |
| 2066 | setup_string_in_str(&input, s); |
| 2067 | return parse_stream_outer(&input); |
| 2068 | } |
| 2069 | |
| 2070 | static int parse_file_outer(FILE *f) |
| 2071 | { |
| 2072 | int rcode; |
| 2073 | struct in_str input; |
| 2074 | setup_file_in_str(&input, f); |
| 2075 | rcode = parse_stream_outer(&input); |
| 2076 | return rcode; |
| 2077 | } |
| 2078 | |
| 2079 | int shell_main(int argc, char **argv) |
| 2080 | { |
| 2081 | int opt; |
| 2082 | FILE *input; |
| 2083 | |
| 2084 | /* XXX what should these be while sourcing /etc/profile? */ |
| 2085 | global_argc = argc; |
| 2086 | global_argv = argv; |
| 2087 | |
| 2088 | if (argv[0] && argv[0][0] == '-') { |
| 2089 | debug_printf("\nsourcing /etc/profile\n"); |
| 2090 | input = xfopen("/etc/profile", "r"); |
| 2091 | mark_open(fileno(input)); |
| 2092 | parse_file_outer(input); |
| 2093 | mark_closed(fileno(input)); |
| 2094 | fclose(input); |
| 2095 | } |
| 2096 | input=stdin; |
| 2097 | |
| 2098 | /* initialize the cwd -- this is never freed...*/ |
| 2099 | cwd = xgetcwd(0); |
| 2100 | #ifdef BB_FEATURE_COMMAND_EDITING |
| 2101 | cmdedit_set_initial_prompt(); |
| 2102 | #else |
| 2103 | PS1 = NULL; |
| 2104 | #endif |
| 2105 | |
| 2106 | while ((opt = getopt(argc, argv, "c:xif")) > 0) { |
| 2107 | switch (opt) { |
| 2108 | case 'c': |
| 2109 | { |
| 2110 | global_argv = argv+optind; |
| 2111 | global_argc = argc-optind; |
| 2112 | opt = parse_string_outer(optarg); |
| 2113 | exit(opt); |
| 2114 | } |
| 2115 | break; |
| 2116 | case 'i': |
| 2117 | interactive++; |
| 2118 | break; |
| 2119 | case 'f': |
| 2120 | fake_mode++; |
| 2121 | break; |
| 2122 | default: |
| 2123 | fprintf(stderr, "Usage: sh [FILE]...\n" |
| 2124 | " or: sh -c command [args]...\n\n"); |
| 2125 | exit(EXIT_FAILURE); |
| 2126 | } |
| 2127 | } |
| 2128 | /* A shell is interactive if the `-i' flag was given, or if all of |
| 2129 | * the following conditions are met: |
| 2130 | * no -c command |
| 2131 | * no arguments remaining or the -s flag given |
| 2132 | * standard input is a terminal |
| 2133 | * standard output is a terminal |
| 2134 | * Refer to Posix.2, the description of the `sh' utility. */ |
| 2135 | if (argv[optind]==NULL && input==stdin && |
| 2136 | isatty(fileno(stdin)) && isatty(fileno(stdout))) { |
| 2137 | interactive++; |
| 2138 | } |
| 2139 | |
| 2140 | if (interactive) { |
| 2141 | /* Looks like they want an interactive shell */ |
| 2142 | fprintf(stdout, "\nhush -- the humble shell v0.01 (testing)\n\n"); |
| 2143 | exit(parse_file_outer(stdin)); |
| 2144 | } |
| 2145 | debug_printf("\ninteractive=%d\n", interactive); |
| 2146 | |
| 2147 | debug_printf("\nrunning script '%s'\n", argv[optind]); |
| 2148 | global_argv = argv+optind; |
| 2149 | global_argc = argc-optind; |
| 2150 | input = xfopen(argv[optind], "r"); |
| 2151 | opt = parse_file_outer(input); |
| 2152 | |
| 2153 | #ifdef BB_FEATURE_CLEAN_UP |
| 2154 | fclose(input.file); |
| 2155 | #endif |
| 2156 | |
| 2157 | return(opt); |
| 2158 | } |