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1 | /* execute_command.c -- Execute a COMMAND structure. */ |
2 | ||
3 | /* Copyright (C) 1987,1991 Free Software Foundation, Inc. | |
4 | ||
5 | This file is part of GNU Bash, the Bourne Again SHell. | |
6 | ||
7 | Bash is free software; you can redistribute it and/or modify it | |
8 | under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 1, or (at your option) | |
10 | any later version. | |
11 | ||
12 | Bash is distributed in the hope that it will be useful, but WITHOUT | |
13 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY | |
14 | or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public | |
15 | License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with Bash; see the file COPYING. If not, write to the Free | |
19 | Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
20 | #if defined (AIX) && defined (RISC6000) && !defined (__GNUC__) | |
21 | #pragma alloca | |
22 | #endif /* AIX && RISC6000 && !__GNUC__ */ | |
23 | ||
24 | #include <stdio.h> | |
25 | #include <ctype.h> | |
26 | #include "bashtypes.h" | |
27 | #include <sys/file.h> | |
28 | #include "filecntl.h" | |
29 | #include "posixstat.h" | |
30 | #include <signal.h> | |
31 | ||
32 | #if !defined (SIGABRT) | |
33 | #define SIGABRT SIGIOT | |
34 | #endif | |
35 | ||
36 | #include <sys/param.h> | |
37 | #include <errno.h> | |
38 | ||
39 | #if !defined (errno) | |
40 | extern int errno; | |
41 | #endif | |
42 | ||
43 | #if defined (HAVE_STRING_H) | |
44 | # include <string.h> | |
45 | #else /* !HAVE_STRING_H */ | |
46 | # include <strings.h> | |
47 | #endif /* !HAVE_STRING_H */ | |
48 | ||
49 | #include "shell.h" | |
50 | #include "y.tab.h" | |
51 | #include "flags.h" | |
52 | #include "hash.h" | |
53 | #include "jobs.h" | |
54 | #include "execute_cmd.h" | |
55 | ||
56 | #include "sysdefs.h" | |
57 | #include "builtins/common.h" | |
58 | #include "builtins/builtext.h" /* list of builtins */ | |
59 | ||
60 | #include <glob/fnmatch.h> | |
61 | #include <tilde/tilde.h> | |
62 | ||
63 | #if defined (BUFFERED_INPUT) | |
64 | # include "input.h" | |
65 | #endif | |
66 | ||
67 | extern int posixly_correct; | |
68 | extern int breaking, continuing, loop_level; | |
69 | extern int interactive, interactive_shell, login_shell; | |
70 | extern int parse_and_execute_level; | |
71 | extern int command_string_index, variable_context, line_number; | |
72 | extern int dot_found_in_search; | |
73 | extern char **temporary_env, **function_env, **builtin_env; | |
74 | extern char *the_printed_command, *shell_name; | |
75 | extern pid_t last_command_subst_pid; | |
76 | extern Function *last_shell_builtin, *this_shell_builtin; | |
77 | extern jmp_buf top_level, subshell_top_level; | |
78 | extern int subshell_argc; | |
79 | extern char **subshell_argv, **subshell_envp; | |
80 | extern int already_making_children; | |
81 | ||
82 | extern int getdtablesize (); | |
83 | extern int close (); | |
84 | ||
85 | /* Static functions defined and used in this file. */ | |
86 | static void close_pipes (), do_piping (), execute_disk_command (); | |
87 | static void execute_subshell_builtin_or_function (); | |
88 | static void cleanup_redirects (), cleanup_func_redirects (), bind_lastarg (); | |
89 | static void add_undo_close_redirect (), add_exec_redirect (); | |
90 | static int do_redirection_internal (), do_redirections (); | |
91 | static int expandable_redirection_filename (), execute_shell_script (); | |
92 | static int execute_builtin_or_function (), add_undo_redirect (); | |
93 | static char *find_user_command_internal (), *find_user_command_in_path (); | |
94 | ||
95 | /* The line number that the currently executing function starts on. */ | |
96 | static int function_line_number = 0; | |
97 | ||
98 | /* Set to 1 if fd 0 was the subject of redirection to a subshell. */ | |
99 | static int stdin_redir = 0; | |
100 | ||
101 | /* The name of the command that is currently being executed. | |
102 | `test' needs this, for example. */ | |
103 | char *this_command_name; | |
104 | ||
105 | struct stat SB; /* used for debugging */ | |
106 | ||
107 | static REDIRECTEE rd; | |
108 | ||
109 | /* For catching RETURN in a function. */ | |
110 | int return_catch_flag = 0; | |
111 | int return_catch_value; | |
112 | jmp_buf return_catch; | |
113 | ||
114 | /* The value returned by the last synchronous command. */ | |
115 | int last_command_exit_value = 0; | |
116 | ||
117 | /* The list of redirections to perform which will undo the redirections | |
118 | that I made in the shell. */ | |
119 | REDIRECT *redirection_undo_list = (REDIRECT *)NULL; | |
120 | ||
121 | /* The list of redirections to perform which will undo the internal | |
122 | redirections performed by the `exec' builtin. These are redirections | |
123 | that must be undone even when exec discards redirection_undo_list. */ | |
124 | REDIRECT *exec_redirection_undo_list = (REDIRECT *)NULL; | |
125 | ||
126 | /* Non-zero if we have just forked and are currently running in a subshell | |
127 | environment. */ | |
128 | int subshell_environment = 0; | |
129 | ||
130 | struct fd_bitmap *current_fds_to_close = (struct fd_bitmap *)NULL; | |
131 | ||
132 | #define FD_BITMAP_DEFAULT_SIZE 32 | |
133 | /* Functions to allocate and deallocate the structures used to pass | |
134 | information from the shell to its children about file descriptors | |
135 | to close. */ | |
136 | struct fd_bitmap * | |
137 | new_fd_bitmap (size) | |
138 | long size; | |
139 | { | |
140 | struct fd_bitmap *ret; | |
141 | ||
142 | ret = (struct fd_bitmap *)xmalloc (sizeof (struct fd_bitmap)); | |
143 | ||
144 | ret->size = size; | |
145 | ||
146 | if (size) | |
147 | { | |
148 | ret->bitmap = xmalloc (size); | |
149 | bzero (ret->bitmap, size); | |
150 | } | |
151 | else | |
152 | ret->bitmap = (char *)NULL; | |
153 | return (ret); | |
154 | } | |
155 | ||
156 | void | |
157 | dispose_fd_bitmap (fdbp) | |
158 | struct fd_bitmap *fdbp; | |
159 | { | |
160 | FREE (fdbp->bitmap); | |
161 | free (fdbp); | |
162 | } | |
163 | ||
164 | void | |
165 | close_fd_bitmap (fdbp) | |
166 | struct fd_bitmap *fdbp; | |
167 | { | |
168 | register int i; | |
169 | ||
170 | if (fdbp) | |
171 | { | |
172 | for (i = 0; i < fdbp->size; i++) | |
173 | if (fdbp->bitmap[i]) | |
174 | { | |
175 | close (i); | |
176 | fdbp->bitmap[i] = 0; | |
177 | } | |
178 | } | |
179 | } | |
180 | ||
181 | /* Execute the command passed in COMMAND. COMMAND is exactly what | |
182 | read_command () places into GLOBAL_COMMAND. See "command.h" for the | |
183 | details of the command structure. | |
184 | ||
185 | EXECUTION_SUCCESS or EXECUTION_FAILURE are the only possible | |
186 | return values. Executing a command with nothing in it returns | |
187 | EXECUTION_SUCCESS. */ | |
188 | execute_command (command) | |
189 | COMMAND *command; | |
190 | { | |
191 | struct fd_bitmap *bitmap; | |
192 | int result; | |
193 | ||
194 | current_fds_to_close = (struct fd_bitmap *)NULL; | |
195 | bitmap = new_fd_bitmap (FD_BITMAP_DEFAULT_SIZE); | |
196 | begin_unwind_frame ("execute-command"); | |
197 | add_unwind_protect (dispose_fd_bitmap, (char *)bitmap); | |
198 | ||
199 | /* Just do the command, but not asynchronously. */ | |
200 | result = execute_command_internal (command, 0, NO_PIPE, NO_PIPE, bitmap); | |
201 | ||
202 | dispose_fd_bitmap (bitmap); | |
203 | discard_unwind_frame ("execute-command"); | |
204 | ||
205 | #if defined (PROCESS_SUBSTITUTION) | |
206 | unlink_fifo_list (); | |
207 | #endif /* PROCESS_SUBSTITUTION */ | |
208 | ||
209 | return (result); | |
210 | } | |
211 | ||
212 | /* Return 1 if TYPE is a shell control structure type. */ | |
213 | static int | |
214 | shell_control_structure (type) | |
215 | enum command_type type; | |
216 | { | |
217 | switch (type) | |
218 | { | |
219 | case cm_for: | |
220 | #if defined (SELECT_COMMAND) | |
221 | case cm_select: | |
222 | #endif | |
223 | case cm_case: | |
224 | case cm_while: | |
225 | case cm_until: | |
226 | case cm_if: | |
227 | case cm_group: | |
228 | return (1); | |
229 | ||
230 | default: | |
231 | return (0); | |
232 | } | |
233 | } | |
234 | ||
235 | /* A function to use to unwind_protect the redirection undo list | |
236 | for loops. */ | |
237 | static void | |
238 | cleanup_redirects (list) | |
239 | REDIRECT *list; | |
240 | { | |
241 | do_redirections (list, 1, 0, 0); | |
242 | dispose_redirects (list); | |
243 | } | |
244 | ||
245 | /* Function to unwind_protect the redirections for functions and builtins. */ | |
246 | static void | |
247 | cleanup_func_redirects (list) | |
248 | REDIRECT *list; | |
249 | { | |
250 | do_redirections (list, 1, 0, 0); | |
251 | } | |
252 | ||
253 | static void | |
254 | dispose_exec_redirects () | |
255 | { | |
256 | if (exec_redirection_undo_list) | |
257 | { | |
258 | dispose_redirects (exec_redirection_undo_list); | |
259 | exec_redirection_undo_list = (REDIRECT *)NULL; | |
260 | } | |
261 | } | |
262 | ||
263 | #if defined (JOB_CONTROL) | |
264 | /* A function to restore the signal mask to its proper value when the shell | |
265 | is interrupted or errors occur while creating a pipeline. */ | |
266 | static int | |
267 | restore_signal_mask (set) | |
268 | sigset_t set; | |
269 | { | |
270 | return (sigprocmask (SIG_SETMASK, &set, (sigset_t *)NULL)); | |
271 | } | |
272 | #endif /* JOB_CONTROL */ | |
273 | ||
274 | /* A debugging function that can be called from gdb, for instance. */ | |
275 | void | |
276 | open_files () | |
277 | { | |
278 | register int i; | |
279 | int f, fd_table_size; | |
280 | ||
281 | fd_table_size = getdtablesize (); | |
282 | ||
283 | fprintf (stderr, "pid %d open files:", getpid ()); | |
284 | for (i = 3; i < fd_table_size; i++) | |
285 | { | |
286 | if ((f = fcntl (i, F_GETFD, 0)) != -1) | |
287 | fprintf (stderr, " %d (%s)", i, f ? "close" : "open"); | |
288 | } | |
289 | fprintf (stderr, "\n"); | |
290 | } | |
291 | ||
292 | #define DESCRIBE_PID(pid) if (interactive) describe_pid (pid) | |
293 | ||
294 | /* Execute the command passed in COMMAND, perhaps doing it asynchrounously. | |
295 | COMMAND is exactly what read_command () places into GLOBAL_COMMAND. | |
296 | ASYNCHROUNOUS, if non-zero, says to do this command in the background. | |
297 | PIPE_IN and PIPE_OUT are file descriptors saying where input comes | |
298 | from and where it goes. They can have the value of NO_PIPE, which means | |
299 | I/O is stdin/stdout. | |
300 | FDS_TO_CLOSE is a list of file descriptors to close once the child has | |
301 | been forked. This list often contains the unusable sides of pipes, etc. | |
302 | ||
303 | EXECUTION_SUCCESS or EXECUTION_FAILURE are the only possible | |
304 | return values. Executing a command with nothing in it returns | |
305 | EXECUTION_SUCCESS. */ | |
306 | execute_command_internal (command, asynchronous, pipe_in, pipe_out, | |
307 | fds_to_close) | |
308 | COMMAND *command; | |
309 | int asynchronous; | |
310 | int pipe_in, pipe_out; | |
311 | struct fd_bitmap *fds_to_close; | |
312 | { | |
313 | int exec_result = EXECUTION_SUCCESS; | |
314 | int invert, ignore_return; | |
315 | REDIRECT *my_undo_list, *exec_undo_list; | |
316 | ||
317 | if (!command || breaking || continuing) | |
318 | return (EXECUTION_SUCCESS); | |
319 | ||
320 | run_pending_traps (); | |
321 | ||
322 | invert = (command->flags & CMD_INVERT_RETURN) != 0; | |
323 | ||
324 | /* If a command was being explicitly run in a subshell, or if it is | |
325 | a shell control-structure, and it has a pipe, then we do the command | |
326 | in a subshell. */ | |
327 | ||
328 | if ((command->flags & CMD_WANT_SUBSHELL) || | |
329 | (command->flags & CMD_FORCE_SUBSHELL) || | |
330 | (shell_control_structure (command->type) && | |
331 | (pipe_out != NO_PIPE || pipe_in != NO_PIPE || asynchronous))) | |
332 | { | |
333 | pid_t paren_pid; | |
334 | ||
335 | /* Fork a subshell, turn off the subshell bit, turn off job | |
336 | control and call execute_command () on the command again. */ | |
337 | paren_pid = make_child (savestring (make_command_string (command)), | |
338 | asynchronous); | |
339 | if (paren_pid == 0) | |
340 | { | |
341 | int user_subshell, return_code, function_value; | |
342 | ||
343 | /* Cancel traps, in trap.c. */ | |
344 | restore_original_signals (); | |
345 | if (asynchronous) | |
346 | setup_async_signals (); | |
347 | ||
348 | #if defined (JOB_CONTROL) | |
349 | set_sigchld_handler (); | |
350 | #endif /* JOB_CONTROL */ | |
351 | ||
352 | set_sigint_handler (); | |
353 | ||
354 | user_subshell = (command->flags & CMD_WANT_SUBSHELL) != 0; | |
355 | command->flags &= ~(CMD_FORCE_SUBSHELL | CMD_WANT_SUBSHELL | CMD_INVERT_RETURN); | |
356 | ||
357 | /* If a command is asynchronous in a subshell (like ( foo ) & or | |
358 | the special case of an asynchronous GROUP command where the | |
359 | the subshell bit is turned on down in case cm_group: below), | |
360 | turn off `asynchronous', so that two subshells aren't spawned. | |
361 | ||
362 | This seems semantically correct to me. For example, | |
363 | ( foo ) & seems to say ``do the command `foo' in a subshell | |
364 | environment, but don't wait for that subshell to finish'', | |
365 | and "{ foo ; bar } &" seems to me to be like functions or | |
366 | builtins in the background, which executed in a subshell | |
367 | environment. I just don't see the need to fork two subshells. */ | |
368 | ||
369 | /* Don't fork again, we are already in a subshell. A `doubly | |
370 | async' shell is not interactive, however. */ | |
371 | if (asynchronous) | |
372 | { | |
373 | #if defined (JOB_CONTROL) | |
374 | /* If a construct like ( exec xxx yyy ) & is given while job | |
375 | control is active, we want to prevent exec from putting the | |
376 | subshell back into the original process group, carefully | |
377 | undoing all the work we just did in make_child. */ | |
378 | original_pgrp = -1; | |
379 | #endif /* JOB_CONTROL */ | |
380 | interactive_shell = 0; | |
381 | asynchronous = 0; | |
382 | } | |
383 | ||
384 | /* Subshells are neither login nor interactive. */ | |
385 | login_shell = interactive = 0; | |
386 | ||
387 | subshell_environment = 1; | |
388 | ||
389 | #if defined (JOB_CONTROL) | |
390 | /* Delete all traces that there were any jobs running. This is | |
391 | only for subshells. */ | |
392 | without_job_control (); | |
393 | #endif /* JOB_CONTROL */ | |
394 | do_piping (pipe_in, pipe_out); | |
395 | ||
396 | /* If this is a user subshell, set a flag if stdin was redirected. | |
397 | This is used later to decide whether to redirect fd 0 to | |
398 | /dev/null for async commands in the subshell. This adds more | |
399 | sh compatibility, but I'm not sure it's the right thing to do. */ | |
400 | if (user_subshell) | |
401 | { | |
402 | REDIRECT *r; | |
403 | ||
404 | for (r = command->redirects; r; r = r->next) | |
405 | switch (r->instruction) | |
406 | { | |
407 | case r_input_direction: | |
408 | case r_inputa_direction: | |
409 | case r_input_output: | |
410 | case r_reading_until: | |
411 | case r_deblank_reading_until: | |
412 | stdin_redir++; | |
413 | break; | |
414 | case r_duplicating_input: | |
415 | case r_duplicating_input_word: | |
416 | case r_close_this: | |
417 | if (r->redirector == 0) | |
418 | stdin_redir++; | |
419 | break; | |
420 | } | |
421 | } | |
422 | ||
423 | if (fds_to_close) | |
424 | close_fd_bitmap (fds_to_close); | |
425 | ||
426 | /* Do redirections, then dispose of them before recursive call. */ | |
427 | if (command->redirects) | |
428 | { | |
429 | if (do_redirections (command->redirects, 1, 0, 0) != 0) | |
430 | exit (EXECUTION_FAILURE); | |
431 | ||
432 | dispose_redirects (command->redirects); | |
433 | command->redirects = (REDIRECT *)NULL; | |
434 | } | |
435 | ||
436 | /* If this is a simple command, tell execute_disk_command that it | |
437 | might be able to get away without forking and simply exec. | |
438 | This means things like ( sleep 10 ) will only cause one fork. */ | |
439 | if (user_subshell && command->type == cm_simple) | |
440 | { | |
441 | command->flags |= CMD_NO_FORK; | |
442 | command->value.Simple->flags |= CMD_NO_FORK; | |
443 | } | |
444 | ||
445 | /* If we're inside a function while executing this subshell, we | |
446 | need to handle a possible `return'. */ | |
447 | function_value = 0; | |
448 | if (return_catch_flag) | |
449 | function_value = setjmp (return_catch); | |
450 | ||
451 | if (function_value) | |
452 | return_code = return_catch_value; | |
453 | else | |
454 | return_code = execute_command_internal | |
455 | (command, asynchronous, NO_PIPE, NO_PIPE, fds_to_close); | |
456 | ||
457 | /* If we were explicitly placed in a subshell with (), we need | |
458 | to do the `shell cleanup' things, such as running traps[0]. */ | |
459 | if (user_subshell && signal_is_trapped (0)) | |
460 | { | |
461 | last_command_exit_value = return_code; | |
462 | return_code = run_exit_trap (); | |
463 | } | |
464 | ||
465 | exit (return_code); | |
466 | } | |
467 | else | |
468 | { | |
469 | close_pipes (pipe_in, pipe_out); | |
470 | ||
471 | #if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD) | |
472 | unlink_fifo_list (); | |
473 | #endif | |
474 | /* If we are part of a pipeline, and not the end of the pipeline, | |
475 | then we should simply return and let the last command in the | |
476 | pipe be waited for. If we are not in a pipeline, or are the | |
477 | last command in the pipeline, then we wait for the subshell | |
478 | and return its exit status as usual. */ | |
479 | if (pipe_out != NO_PIPE) | |
480 | return (EXECUTION_SUCCESS); | |
481 | ||
482 | stop_pipeline (asynchronous, (COMMAND *)NULL); | |
483 | ||
484 | if (!asynchronous) | |
485 | { | |
486 | last_command_exit_value = wait_for (paren_pid); | |
487 | ||
488 | /* If we have to, invert the return value. */ | |
489 | if (invert) | |
490 | { | |
491 | if (last_command_exit_value == EXECUTION_SUCCESS) | |
492 | return (EXECUTION_FAILURE); | |
493 | else | |
494 | return (EXECUTION_SUCCESS); | |
495 | } | |
496 | else | |
497 | return (last_command_exit_value); | |
498 | } | |
499 | else | |
500 | { | |
501 | DESCRIBE_PID (paren_pid); | |
502 | ||
503 | run_pending_traps (); | |
504 | ||
505 | return (EXECUTION_SUCCESS); | |
506 | } | |
507 | } | |
508 | } | |
509 | ||
510 | /* Handle WHILE FOR CASE etc. with redirections. (Also '&' input | |
511 | redirection.) */ | |
512 | if (do_redirections (command->redirects, 1, 1, 0) != 0) | |
513 | { | |
514 | cleanup_redirects (redirection_undo_list); | |
515 | redirection_undo_list = (REDIRECT *)NULL; | |
516 | dispose_exec_redirects (); | |
517 | return (EXECUTION_FAILURE); | |
518 | } | |
519 | ||
520 | if (redirection_undo_list) | |
521 | { | |
522 | my_undo_list = (REDIRECT *)copy_redirects (redirection_undo_list); | |
523 | dispose_redirects (redirection_undo_list); | |
524 | redirection_undo_list = (REDIRECT *)NULL; | |
525 | } | |
526 | else | |
527 | my_undo_list = (REDIRECT *)NULL; | |
528 | ||
529 | if (exec_redirection_undo_list) | |
530 | { | |
531 | exec_undo_list = (REDIRECT *)copy_redirects (exec_redirection_undo_list); | |
532 | dispose_redirects (exec_redirection_undo_list); | |
533 | exec_redirection_undo_list = (REDIRECT *)NULL; | |
534 | } | |
535 | else | |
536 | exec_undo_list = (REDIRECT *)NULL; | |
537 | ||
538 | if (my_undo_list || exec_undo_list) | |
539 | begin_unwind_frame ("loop_redirections"); | |
540 | ||
541 | if (my_undo_list) | |
542 | add_unwind_protect ((Function *)cleanup_redirects, my_undo_list); | |
543 | ||
544 | if (exec_undo_list) | |
545 | add_unwind_protect ((Function *)dispose_redirects, exec_undo_list); | |
546 | ||
547 | ignore_return = (command->flags & CMD_IGNORE_RETURN) != 0; | |
548 | ||
549 | QUIT; | |
550 | ||
551 | switch (command->type) | |
552 | { | |
553 | case cm_for: | |
554 | if (ignore_return) | |
555 | command->value.For->flags |= CMD_IGNORE_RETURN; | |
556 | exec_result = execute_for_command (command->value.For); | |
557 | break; | |
558 | ||
559 | #if defined (SELECT_COMMAND) | |
560 | case cm_select: | |
561 | if (ignore_return) | |
562 | command->value.Select->flags |= CMD_IGNORE_RETURN; | |
563 | exec_result = execute_select_command (command->value.Select); | |
564 | break; | |
565 | #endif | |
566 | ||
567 | case cm_case: | |
568 | if (ignore_return) | |
569 | command->value.Case->flags |= CMD_IGNORE_RETURN; | |
570 | exec_result = execute_case_command (command->value.Case); | |
571 | break; | |
572 | ||
573 | case cm_while: | |
574 | if (ignore_return) | |
575 | command->value.While->flags |= CMD_IGNORE_RETURN; | |
576 | exec_result = execute_while_command (command->value.While); | |
577 | break; | |
578 | ||
579 | case cm_until: | |
580 | if (ignore_return) | |
581 | command->value.While->flags |= CMD_IGNORE_RETURN; | |
582 | exec_result = execute_until_command (command->value.While); | |
583 | break; | |
584 | ||
585 | case cm_if: | |
586 | if (ignore_return) | |
587 | command->value.If->flags |= CMD_IGNORE_RETURN; | |
588 | exec_result = execute_if_command (command->value.If); | |
589 | break; | |
590 | ||
591 | case cm_group: | |
592 | ||
593 | /* This code can be executed from either of two paths: an explicit | |
594 | '{}' command, or via a function call. If we are executed via a | |
595 | function call, we have already taken care of the function being | |
596 | executed in the background (down there in execute_simple_command ()), | |
597 | and this command should *not* be marked as asynchronous. If we | |
598 | are executing a regular '{}' group command, and asynchronous == 1, | |
599 | we must want to execute the whole command in the background, so we | |
600 | need a subshell, and we want the stuff executed in that subshell | |
601 | (this group command) to be executed in the foreground of that | |
602 | subshell (i.e. there will not be *another* subshell forked). | |
603 | ||
604 | What we do is to force a subshell if asynchronous, and then call | |
605 | execute_command_internal again with asynchronous still set to 1, | |
606 | but with the original group command, so the printed command will | |
607 | look right. | |
608 | ||
609 | The code above that handles forking off subshells will note that | |
610 | both subshell and async are on, and turn off async in the child | |
611 | after forking the subshell (but leave async set in the parent, so | |
612 | the normal call to describe_pid is made). This turning off | |
613 | async is *crucial*; if it is not done, this will fall into an | |
614 | infinite loop of executions through this spot in subshell after | |
615 | subshell until the process limit is exhausted. */ | |
616 | ||
617 | if (asynchronous) | |
618 | { | |
619 | command->flags |= CMD_FORCE_SUBSHELL; | |
620 | exec_result = | |
621 | execute_command_internal (command, 1, pipe_in, pipe_out, | |
622 | fds_to_close); | |
623 | } | |
624 | else | |
625 | { | |
626 | if (ignore_return && command->value.Group->command) | |
627 | command->value.Group->command->flags |= CMD_IGNORE_RETURN; | |
628 | exec_result = | |
629 | execute_command_internal (command->value.Group->command, | |
630 | asynchronous, pipe_in, pipe_out, | |
631 | fds_to_close); | |
632 | } | |
633 | break; | |
634 | ||
635 | case cm_simple: | |
636 | { | |
637 | /* We can't rely on this variable retaining its value across a | |
638 | call to execute_simple_command if a longjmp occurs as the | |
639 | result of a `return' builtin. This is true for sure with gcc. */ | |
640 | pid_t last_pid = last_made_pid; | |
641 | ||
642 | if (ignore_return && command->value.Simple) | |
643 | command->value.Simple->flags |= CMD_IGNORE_RETURN; | |
644 | exec_result = | |
645 | execute_simple_command (command->value.Simple, pipe_in, pipe_out, | |
646 | asynchronous, fds_to_close); | |
647 | ||
648 | /* The temporary environment should be used for only the simple | |
649 | command immediately following its definition. */ | |
650 | dispose_used_env_vars (); | |
651 | ||
652 | #if (defined (Ultrix) && defined (mips)) || !defined (HAVE_ALLOCA) | |
653 | /* Reclaim memory allocated with alloca () on machines which | |
654 | may be using the alloca emulation code. */ | |
655 | (void) alloca (0); | |
656 | #endif /* (Ultrix && mips) || !HAVE_ALLOCA */ | |
657 | ||
658 | /* If we forked to do the command, then we must wait_for () | |
659 | the child. */ | |
660 | ||
661 | /* XXX - this is something to watch out for if there are problems | |
662 | when the shell is compiled without job control. */ | |
663 | if (already_making_children && pipe_out == NO_PIPE && | |
664 | last_pid != last_made_pid) | |
665 | { | |
666 | stop_pipeline (asynchronous, (COMMAND *)NULL); | |
667 | ||
668 | if (asynchronous) | |
669 | { | |
670 | DESCRIBE_PID (last_made_pid); | |
671 | } | |
672 | else | |
673 | #if !defined (JOB_CONTROL) | |
674 | /* Do not wait for asynchronous processes started from | |
675 | startup files. */ | |
676 | if (last_made_pid != last_asynchronous_pid) | |
677 | #endif | |
678 | /* When executing a shell function that executes other | |
679 | commands, this causes the last simple command in | |
680 | the function to be waited for twice. */ | |
681 | exec_result = wait_for (last_made_pid); | |
682 | } | |
683 | } | |
684 | ||
685 | if (!ignore_return && exit_immediately_on_error && !invert && | |
686 | (exec_result != EXECUTION_SUCCESS)) | |
687 | { | |
688 | last_command_exit_value = exec_result; | |
689 | run_pending_traps (); | |
690 | longjmp (top_level, EXITPROG); | |
691 | } | |
692 | ||
693 | break; | |
694 | ||
695 | case cm_connection: | |
696 | switch (command->value.Connection->connector) | |
697 | { | |
698 | /* Do the first command asynchronously. */ | |
699 | case '&': | |
700 | { | |
701 | COMMAND *tc = command->value.Connection->first; | |
702 | REDIRECT *rp; | |
703 | ||
704 | if (!tc) | |
705 | break; | |
706 | ||
707 | rp = tc->redirects; | |
708 | ||
709 | if (ignore_return && tc) | |
710 | tc->flags |= CMD_IGNORE_RETURN; | |
711 | ||
712 | /* If this shell was compiled without job control support, if | |
713 | the shell is not running interactively, if we are currently | |
714 | in a subshell via `( xxx )', or if job control is not active | |
715 | then the standard input for an asynchronous command is | |
716 | forced to /dev/null. */ | |
717 | #if defined (JOB_CONTROL) | |
718 | if ((!interactive_shell || subshell_environment || !job_control) && | |
719 | !stdin_redir) | |
720 | #else | |
721 | if (!stdin_redir) | |
722 | #endif /* JOB_CONTROL */ | |
723 | { | |
724 | REDIRECT *tr; | |
725 | ||
726 | rd.filename = make_word ("/dev/null"); | |
727 | tr = make_redirection (0, r_inputa_direction, rd); | |
728 | tr->next = tc->redirects; | |
729 | tc->redirects = tr; | |
730 | } | |
731 | ||
732 | exec_result = execute_command_internal | |
733 | (tc, 1, pipe_in, pipe_out, fds_to_close); | |
734 | ||
735 | #if defined (JOB_CONTROL) | |
736 | if ((!interactive_shell || subshell_environment || !job_control) && | |
737 | !stdin_redir) | |
738 | #else | |
739 | if (!stdin_redir) | |
740 | #endif /* JOB_CONTROL */ | |
741 | { | |
742 | /* Remove the redirection we added above. It matters, | |
743 | especially for loops, which call execute_command () | |
744 | multiple times with the same command. */ | |
745 | REDIRECT *tr, *tl; | |
746 | ||
747 | tr = tc->redirects; | |
748 | do | |
749 | { | |
750 | tl = tc->redirects; | |
751 | tc->redirects = tc->redirects->next; | |
752 | } | |
753 | while (tc->redirects && tc->redirects != rp); | |
754 | ||
755 | tl->next = (REDIRECT *)NULL; | |
756 | dispose_redirects (tr); | |
757 | } | |
758 | ||
759 | { | |
760 | register COMMAND *second; | |
761 | ||
762 | second = command->value.Connection->second; | |
763 | ||
764 | if (second) | |
765 | { | |
766 | if (ignore_return) | |
767 | second->flags |= CMD_IGNORE_RETURN; | |
768 | ||
769 | exec_result = execute_command_internal | |
770 | (second, asynchronous, pipe_in, pipe_out, fds_to_close); | |
771 | } | |
772 | } | |
773 | } | |
774 | break; | |
775 | ||
776 | case ';': | |
777 | /* Just call execute command on both of them. */ | |
778 | if (ignore_return) | |
779 | { | |
780 | if (command->value.Connection->first) | |
781 | command->value.Connection->first->flags |= CMD_IGNORE_RETURN; | |
782 | if (command->value.Connection->second) | |
783 | command->value.Connection->second->flags |= CMD_IGNORE_RETURN; | |
784 | } | |
785 | QUIT; | |
786 | execute_command (command->value.Connection->first); | |
787 | QUIT; | |
788 | exec_result = | |
789 | execute_command_internal (command->value.Connection->second, | |
790 | asynchronous, pipe_in, pipe_out, | |
791 | fds_to_close); | |
792 | break; | |
793 | ||
794 | case '|': | |
795 | { | |
796 | int prev, fildes[2], new_bitmap_size, dummyfd; | |
797 | COMMAND *cmd; | |
798 | struct fd_bitmap *fd_bitmap; | |
799 | ||
800 | #if defined (JOB_CONTROL) | |
801 | sigset_t set, oset; | |
802 | BLOCK_CHILD (set, oset); | |
803 | #endif /* JOB_CONTROL */ | |
804 | ||
805 | prev = pipe_in; | |
806 | cmd = command; | |
807 | ||
808 | while (cmd && | |
809 | cmd->type == cm_connection && | |
810 | cmd->value.Connection && | |
811 | cmd->value.Connection->connector == '|') | |
812 | { | |
813 | /* Make a pipeline between the two commands. */ | |
814 | if (pipe (fildes) < 0) | |
815 | { | |
816 | report_error ("pipe error: %s", strerror (errno)); | |
817 | #if defined (JOB_CONTROL) | |
818 | terminate_current_pipeline (); | |
819 | kill_current_pipeline (); | |
820 | #endif /* JOB_CONTROL */ | |
821 | last_command_exit_value = EXECUTION_FAILURE; | |
822 | /* The unwind-protects installed below will take care | |
823 | of closing all of the open file descriptors. */ | |
824 | throw_to_top_level (); | |
825 | } | |
826 | else | |
827 | { | |
828 | /* Here is a problem: with the new file close-on-exec | |
829 | code, the read end of the pipe (fildes[0]) stays open | |
830 | in the first process, so that process will never get a | |
831 | SIGPIPE. There is no way to signal the first process | |
832 | that it should close fildes[0] after forking, so it | |
833 | remains open. No SIGPIPE is ever sent because there | |
834 | is still a file descriptor open for reading connected | |
835 | to the pipe. We take care of that here. This passes | |
836 | around a bitmap of file descriptors that must be | |
837 | closed after making a child process in | |
838 | execute_simple_command. */ | |
839 | ||
840 | /* We need fd_bitmap to be at least as big as fildes[0]. | |
841 | If fildes[0] is less than fds_to_close->size, then | |
842 | use fds_to_close->size. */ | |
843 | if (fildes[0] < fds_to_close->size) | |
844 | new_bitmap_size = fds_to_close->size; | |
845 | else | |
846 | new_bitmap_size = fildes[0] + 8; | |
847 | ||
848 | fd_bitmap = new_fd_bitmap (new_bitmap_size); | |
849 | ||
850 | /* Now copy the old information into the new bitmap. */ | |
851 | xbcopy ((char *)fds_to_close->bitmap, | |
852 | (char *)fd_bitmap->bitmap, fds_to_close->size); | |
853 | ||
854 | /* And mark the pipe file descriptors to be closed. */ | |
855 | fd_bitmap->bitmap[fildes[0]] = 1; | |
856 | ||
857 | /* In case there are pipe or out-of-processes errors, we | |
858 | want all these file descriptors to be closed when | |
859 | unwind-protects are run, and the storage used for the | |
860 | bitmaps freed up. */ | |
861 | begin_unwind_frame ("pipe-file-descriptors"); | |
862 | add_unwind_protect (dispose_fd_bitmap, fd_bitmap); | |
863 | add_unwind_protect (close_fd_bitmap, fd_bitmap); | |
864 | if (prev >= 0) | |
865 | add_unwind_protect (close, prev); | |
866 | dummyfd = fildes[1]; | |
867 | add_unwind_protect (close, dummyfd); | |
868 | ||
869 | #if defined (JOB_CONTROL) | |
870 | add_unwind_protect (restore_signal_mask, oset); | |
871 | #endif /* JOB_CONTROL */ | |
872 | ||
873 | if (ignore_return && cmd->value.Connection->first) | |
874 | cmd->value.Connection->first->flags |= | |
875 | CMD_IGNORE_RETURN; | |
876 | execute_command_internal | |
877 | (cmd->value.Connection->first, asynchronous, prev, | |
878 | fildes[1], fd_bitmap); | |
879 | ||
880 | if (prev >= 0) | |
881 | close (prev); | |
882 | ||
883 | prev = fildes[0]; | |
884 | close (fildes[1]); | |
885 | ||
886 | dispose_fd_bitmap (fd_bitmap); | |
887 | discard_unwind_frame ("pipe-file-descriptors"); | |
888 | } | |
889 | cmd = cmd->value.Connection->second; | |
890 | } | |
891 | ||
892 | /* Now execute the rightmost command in the pipeline. */ | |
893 | if (ignore_return && cmd) | |
894 | cmd->flags |= CMD_IGNORE_RETURN; | |
895 | exec_result = | |
896 | execute_command_internal | |
897 | (cmd, asynchronous, prev, pipe_out, fds_to_close); | |
898 | ||
899 | if (prev >= 0) | |
900 | close (prev); | |
901 | ||
902 | #if defined (JOB_CONTROL) | |
903 | UNBLOCK_CHILD (oset); | |
904 | #endif | |
905 | } | |
906 | break; | |
907 | ||
908 | case AND_AND: | |
909 | case OR_OR: | |
910 | if (asynchronous) | |
911 | { | |
912 | /* If we have something like `a && b &' or `a || b &', run the | |
913 | && or || stuff in a subshell. Force a subshell and just call | |
914 | execute_command_internal again. Leave asynchronous on | |
915 | so that we get a report from the parent shell about the | |
916 | background job. */ | |
917 | command->flags |= CMD_FORCE_SUBSHELL; | |
918 | exec_result = execute_command_internal (command, 1, pipe_in, | |
919 | pipe_out, fds_to_close); | |
920 | break; | |
921 | } | |
922 | ||
923 | /* Execute the first command. If the result of that is successful | |
924 | and the connector is AND_AND, or the result is not successful | |
925 | and the connector is OR_OR, then execute the second command, | |
926 | otherwise return. */ | |
927 | ||
928 | if (command->value.Connection->first) | |
929 | command->value.Connection->first->flags |= CMD_IGNORE_RETURN; | |
930 | ||
931 | exec_result = execute_command (command->value.Connection->first); | |
932 | QUIT; | |
933 | if (((command->value.Connection->connector == AND_AND) && | |
934 | (exec_result == EXECUTION_SUCCESS)) || | |
935 | ((command->value.Connection->connector == OR_OR) && | |
936 | (exec_result != EXECUTION_SUCCESS))) | |
937 | { | |
938 | if (ignore_return && command->value.Connection->second) | |
939 | command->value.Connection->second->flags |= | |
940 | CMD_IGNORE_RETURN; | |
941 | ||
942 | exec_result = | |
943 | execute_command (command->value.Connection->second); | |
944 | } | |
945 | break; | |
946 | ||
947 | default: | |
948 | programming_error ("Bad connector `%d'!", | |
949 | command->value.Connection->connector); | |
950 | longjmp (top_level, DISCARD); | |
951 | break; | |
952 | } | |
953 | break; | |
954 | ||
955 | case cm_function_def: | |
956 | exec_result = intern_function (command->value.Function_def->name, | |
957 | command->value.Function_def->command); | |
958 | break; | |
959 | ||
960 | default: | |
961 | programming_error | |
962 | ("execute_command: Bad command type `%d'!", command->type); | |
963 | } | |
964 | ||
965 | if (my_undo_list) | |
966 | { | |
967 | do_redirections (my_undo_list, 1, 0, 0); | |
968 | dispose_redirects (my_undo_list); | |
969 | } | |
970 | ||
971 | if (exec_undo_list) | |
972 | dispose_redirects (exec_undo_list); | |
973 | ||
974 | if (my_undo_list || exec_undo_list) | |
975 | discard_unwind_frame ("loop_redirections"); | |
976 | ||
977 | /* Invert the return value if we have to */ | |
978 | if (invert) | |
979 | { | |
980 | if (exec_result == EXECUTION_SUCCESS) | |
981 | exec_result = EXECUTION_FAILURE; | |
982 | else | |
983 | exec_result = EXECUTION_SUCCESS; | |
984 | } | |
985 | ||
986 | last_command_exit_value = exec_result; | |
987 | run_pending_traps (); | |
988 | return (last_command_exit_value); | |
989 | } | |
990 | ||
991 | #if defined (JOB_CONTROL) | |
992 | # define REAP() \ | |
993 | do \ | |
994 | { \ | |
995 | if (!interactive_shell) \ | |
996 | reap_dead_jobs (); \ | |
997 | } \ | |
998 | while (0) | |
999 | #else /* !JOB_CONTROL */ | |
1000 | # define REAP() \ | |
1001 | do \ | |
1002 | { \ | |
1003 | if (!interactive_shell) \ | |
1004 | cleanup_dead_jobs (); \ | |
1005 | } \ | |
1006 | while (0) | |
1007 | #endif /* !JOB_CONTROL */ | |
1008 | ||
1009 | ||
1010 | /* Execute a FOR command. The syntax is: FOR word_desc IN word_list; | |
1011 | DO command; DONE */ | |
1012 | execute_for_command (for_command) | |
1013 | FOR_COM *for_command; | |
1014 | { | |
1015 | /* I just noticed that the Bourne shell leaves word_desc bound to the | |
1016 | last name in word_list after the FOR statement is done. This seems | |
1017 | wrong to me; I thought that the variable binding should be lexically | |
1018 | scoped, i.e., only would last the duration of the FOR command. This | |
1019 | behaviour can be gotten by turning on the lexical_scoping switch. */ | |
1020 | ||
1021 | register WORD_LIST *releaser, *list; | |
1022 | char *identifier; | |
1023 | SHELL_VAR *old_value = (SHELL_VAR *)NULL; /* Remember the old value of x. */ | |
1024 | int retval = EXECUTION_SUCCESS; | |
1025 | ||
1026 | if (check_identifier (for_command->name, 1) == 0) | |
1027 | return (EXECUTION_FAILURE); | |
1028 | ||
1029 | loop_level++; | |
1030 | identifier = for_command->name->word; | |
1031 | ||
1032 | list = releaser = expand_words_no_vars (for_command->map_list); | |
1033 | ||
1034 | begin_unwind_frame ("for"); | |
1035 | add_unwind_protect (dispose_words, releaser); | |
1036 | ||
1037 | if (lexical_scoping) | |
1038 | { | |
1039 | old_value = copy_variable (find_variable (identifier)); | |
1040 | if (old_value) | |
1041 | add_unwind_protect (dispose_variable, old_value); | |
1042 | } | |
1043 | ||
1044 | if (for_command->flags & CMD_IGNORE_RETURN) | |
1045 | for_command->action->flags |= CMD_IGNORE_RETURN; | |
1046 | ||
1047 | while (list) | |
1048 | { | |
1049 | QUIT; | |
1050 | bind_variable (identifier, list->word->word); | |
1051 | execute_command (for_command->action); | |
1052 | retval = last_command_exit_value; | |
1053 | REAP (); | |
1054 | QUIT; | |
1055 | ||
1056 | if (breaking) | |
1057 | { | |
1058 | breaking--; | |
1059 | break; | |
1060 | } | |
1061 | ||
1062 | if (continuing) | |
1063 | { | |
1064 | continuing--; | |
1065 | if (continuing) | |
1066 | break; | |
1067 | } | |
1068 | ||
1069 | list = list->next; | |
1070 | } | |
1071 | ||
1072 | loop_level--; | |
1073 | ||
1074 | if (lexical_scoping) | |
1075 | { | |
1076 | if (!old_value) | |
1077 | makunbound (identifier, shell_variables); | |
1078 | else | |
1079 | { | |
1080 | SHELL_VAR *new_value; | |
1081 | ||
1082 | new_value = bind_variable (identifier, value_cell(old_value)); | |
1083 | new_value->attributes = old_value->attributes; | |
1084 | dispose_variable (old_value); | |
1085 | } | |
1086 | } | |
1087 | ||
1088 | dispose_words (releaser); | |
1089 | discard_unwind_frame ("for"); | |
1090 | return (retval); | |
1091 | } | |
1092 | ||
1093 | #if defined (SELECT_COMMAND) | |
1094 | static int LINES, COLS, tabsize; | |
1095 | ||
1096 | #define RP_SPACE ") " | |
1097 | #define RP_SPACE_LEN 2 | |
1098 | ||
1099 | /* XXX - does not handle numbers > 1000000 at all. */ | |
1100 | #define NUMBER_LEN(s) \ | |
1101 | ((s < 10) ? 1 \ | |
1102 | : ((s < 100) ? 2 \ | |
1103 | : ((s < 1000) ? 3 \ | |
1104 | : ((s < 10000) ? 4 \ | |
1105 | : ((s < 100000) ? 5 \ | |
1106 | : 6))))) | |
1107 | ||
1108 | static int | |
1109 | print_index_and_element (len, ind, list) | |
1110 | int len, ind; | |
1111 | WORD_LIST *list; | |
1112 | { | |
1113 | register WORD_LIST *l; | |
1114 | register int i; | |
1115 | ||
1116 | if (list == 0) | |
1117 | return (0); | |
1118 | i = ind; | |
1119 | l = list; | |
1120 | while (l && --i) | |
1121 | l = l->next; | |
1122 | fprintf (stderr, "%*d%s%s", len, ind, RP_SPACE, l->word->word); | |
1123 | return (STRLEN (l->word->word)); | |
1124 | } | |
1125 | ||
1126 | static void | |
1127 | indent (from, to) | |
1128 | int from, to; | |
1129 | { | |
1130 | while (from < to) | |
1131 | { | |
1132 | if ((to / tabsize) > (from / tabsize)) | |
1133 | { | |
1134 | putc ('\t', stderr); | |
1135 | from += tabsize - from % tabsize; | |
1136 | } | |
1137 | else | |
1138 | { | |
1139 | putc (' ', stderr); | |
1140 | from++; | |
1141 | } | |
1142 | } | |
1143 | } | |
1144 | ||
1145 | static void | |
1146 | print_select_list (list, list_len, max_elem_len, indices_len) | |
1147 | WORD_LIST *list; | |
1148 | int list_len, max_elem_len, indices_len; | |
1149 | { | |
1150 | int ind, row, elem_len, pos, cols, rows; | |
1151 | int first_column_indices_len, other_indices_len; | |
1152 | ||
1153 | if (list == 0) | |
1154 | { | |
1155 | putc ('\n', stderr); | |
1156 | return; | |
1157 | } | |
1158 | ||
1159 | cols = COLS / max_elem_len; | |
1160 | if (cols == 0) | |
1161 | cols = 1; | |
1162 | rows = list_len ? list_len / cols + (list_len % cols != 0) : 1; | |
1163 | cols = list_len ? list_len / rows + (list_len % rows != 0) : 1; | |
1164 | ||
1165 | if (rows == 1) | |
1166 | { | |
1167 | rows = cols; | |
1168 | cols = 1; | |
1169 | } | |
1170 | ||
1171 | first_column_indices_len = NUMBER_LEN (rows); | |
1172 | other_indices_len = indices_len; | |
1173 | ||
1174 | for (row = 0; row < rows; row++) | |
1175 | { | |
1176 | ind = row; | |
1177 | pos = 0; | |
1178 | while (1) | |
1179 | { | |
1180 | indices_len = (pos == 0) ? first_column_indices_len : other_indices_len; | |
1181 | elem_len = print_index_and_element (indices_len, ind + 1, list); | |
1182 | elem_len += indices_len + RP_SPACE_LEN; | |
1183 | ind += rows; | |
1184 | if (ind >= list_len) | |
1185 | break; | |
1186 | indent (pos + elem_len, pos + max_elem_len); | |
1187 | pos += max_elem_len; | |
1188 | } | |
1189 | putc ('\n', stderr); | |
1190 | } | |
1191 | } | |
1192 | ||
1193 | /* Print the elements of LIST, one per line, preceded by an index from 1 to | |
1194 | LIST_LEN. Then display PROMPT and wait for the user to enter a number. | |
1195 | If the number is between 1 and LIST_LEN, return that selection. If EOF | |
1196 | is read, return a null string. If a blank line is entered, the loop is | |
1197 | executed again. */ | |
1198 | static char * | |
1199 | select_query (list, list_len, prompt) | |
1200 | WORD_LIST *list; | |
1201 | int list_len; | |
1202 | char *prompt; | |
1203 | { | |
1204 | int max_elem_len, indices_len, len, reply; | |
1205 | WORD_LIST *l; | |
1206 | char *repl_string, *t; | |
1207 | ||
1208 | t = get_string_value ("LINES"); | |
1209 | LINES = (t && *t) ? atoi (t) : 24; | |
1210 | t = get_string_value ("COLUMNS"); | |
1211 | COLS = (t && *t) ? atoi (t) : 80; | |
1212 | ||
1213 | #if 0 | |
1214 | t = get_string_value ("TABSIZE"); | |
1215 | tabsize = (t && *t) ? atoi (t) : 8; | |
1216 | if (tabsize <= 0) | |
1217 | tabsize = 8; | |
1218 | #else | |
1219 | tabsize = 8; | |
1220 | #endif | |
1221 | ||
1222 | max_elem_len = 0; | |
1223 | for (l = list; l; l = l->next) | |
1224 | { | |
1225 | len = STRLEN (l->word->word); | |
1226 | if (len > max_elem_len) | |
1227 | max_elem_len = len; | |
1228 | } | |
1229 | indices_len = NUMBER_LEN (list_len); | |
1230 | max_elem_len += indices_len + RP_SPACE_LEN + 2; | |
1231 | ||
1232 | while (1) | |
1233 | { | |
1234 | print_select_list (list, list_len, max_elem_len, indices_len); | |
1235 | printf ("%s", prompt); | |
1236 | fflush (stdout); | |
1237 | QUIT; | |
1238 | ||
1239 | if (read_builtin ((WORD_LIST *)NULL) == EXECUTION_FAILURE) | |
1240 | { | |
1241 | putchar ('\n'); | |
1242 | return ((char *)NULL); | |
1243 | } | |
1244 | repl_string = get_string_value ("REPLY"); | |
1245 | if (*repl_string == 0) | |
1246 | continue; | |
1247 | reply = atoi (repl_string); | |
1248 | if (reply < 1 || reply > list_len) | |
1249 | return ""; | |
1250 | ||
1251 | l = list; | |
1252 | while (l && --reply) | |
1253 | l = l->next; | |
1254 | return (l->word->word); | |
1255 | } | |
1256 | } | |
1257 | ||
1258 | /* Execute a SELECT command. The syntax is: | |
1259 | SELECT word IN list DO command_list DONE | |
1260 | Only `break' or `return' in command_list will terminate | |
1261 | the command. */ | |
1262 | execute_select_command (select_command) | |
1263 | SELECT_COM *select_command; | |
1264 | { | |
1265 | WORD_LIST *releaser, *list; | |
1266 | char *identifier, *ps3_prompt, *selection; | |
1267 | int retval, list_len, return_val; | |
1268 | #if 0 | |
1269 | SHELL_VAR *old_value = (SHELL_VAR *)0; | |
1270 | #endif | |
1271 | ||
1272 | ||
1273 | retval = EXECUTION_SUCCESS; | |
1274 | ||
1275 | if (check_identifier (select_command->name, 1) == 0) | |
1276 | return (EXECUTION_FAILURE); | |
1277 | ||
1278 | loop_level++; | |
1279 | identifier = select_command->name->word; | |
1280 | ||
1281 | /* command and arithmetic substitution, parameter and variable expansion, | |
1282 | word splitting, pathname expansion, and quote removal. */ | |
1283 | list = releaser = expand_words_no_vars (select_command->map_list); | |
1284 | list_len = list_length (list); | |
1285 | if (list == 0 || list_len == 0) | |
1286 | { | |
1287 | if (list) | |
1288 | dispose_words (list); | |
1289 | return (EXECUTION_SUCCESS); | |
1290 | } | |
1291 | ||
1292 | begin_unwind_frame ("select"); | |
1293 | add_unwind_protect (dispose_words, releaser); | |
1294 | ||
1295 | #if 0 | |
1296 | if (lexical_scoping) | |
1297 | { | |
1298 | old_value = copy_variable (find_variable (identifier)); | |
1299 | if (old_value) | |
1300 | add_unwind_protect (dispose_variable, old_value); | |
1301 | } | |
1302 | #endif | |
1303 | ||
1304 | if (select_command->flags & CMD_IGNORE_RETURN) | |
1305 | select_command->action->flags |= CMD_IGNORE_RETURN; | |
1306 | ||
1307 | unwind_protect_int (return_catch_flag); | |
1308 | unwind_protect_jmp_buf (return_catch); | |
1309 | return_catch_flag++; | |
1310 | ||
1311 | while (1) | |
1312 | { | |
1313 | ps3_prompt = get_string_value ("PS3"); | |
1314 | if (!ps3_prompt) | |
1315 | ps3_prompt = "#? "; | |
1316 | ||
1317 | QUIT; | |
1318 | selection = select_query (list, list_len, ps3_prompt); | |
1319 | QUIT; | |
1320 | if (selection == 0) | |
1321 | break; | |
1322 | else | |
1323 | bind_variable (identifier, selection); | |
1324 | ||
1325 | return_val = setjmp (return_catch); | |
1326 | ||
1327 | if (return_val) | |
1328 | { | |
1329 | retval = return_catch_value; | |
1330 | break; | |
1331 | } | |
1332 | else | |
1333 | retval = execute_command (select_command->action); | |
1334 | ||
1335 | REAP (); | |
1336 | QUIT; | |
1337 | ||
1338 | if (breaking) | |
1339 | { | |
1340 | breaking--; | |
1341 | break; | |
1342 | } | |
1343 | } | |
1344 | ||
1345 | loop_level--; | |
1346 | ||
1347 | #if 0 | |
1348 | if (lexical_scoping) | |
1349 | { | |
1350 | if (!old_value) | |
1351 | makunbound (identifier, shell_variables); | |
1352 | else | |
1353 | { | |
1354 | SHELL_VAR *new_value; | |
1355 | ||
1356 | new_value = bind_variable (identifier, value_cell(old_value)); | |
1357 | new_value->attributes = old_value->attributes; | |
1358 | dispose_variable (old_value); | |
1359 | } | |
1360 | } | |
1361 | #endif | |
1362 | ||
1363 | run_unwind_frame ("select"); | |
1364 | return (retval); | |
1365 | } | |
1366 | #endif /* SELECT_COMMAND */ | |
1367 | ||
1368 | /* Execute a CASE command. The syntax is: CASE word_desc IN pattern_list ESAC. | |
1369 | The pattern_list is a linked list of pattern clauses; each clause contains | |
1370 | some patterns to compare word_desc against, and an associated command to | |
1371 | execute. */ | |
1372 | execute_case_command (case_command) | |
1373 | CASE_COM *case_command; | |
1374 | { | |
1375 | register WORD_LIST *list; | |
1376 | WORD_LIST *wlist; | |
1377 | PATTERN_LIST *clauses; | |
1378 | char *word; | |
1379 | int retval; | |
1380 | ||
1381 | /* Posix.2 specifies that the WORD is tilde expanded. */ | |
1382 | if (member ('~', case_command->word->word)) | |
1383 | { | |
1384 | word = tilde_expand (case_command->word->word); | |
1385 | free (case_command->word->word); | |
1386 | case_command->word->word = word; | |
1387 | } | |
1388 | ||
1389 | wlist = expand_word_no_split (case_command->word, 0); | |
1390 | clauses = case_command->clauses; | |
1391 | word = (wlist) ? string_list (wlist) : savestring (""); | |
1392 | retval = EXECUTION_SUCCESS; | |
1393 | ||
1394 | begin_unwind_frame ("case"); | |
1395 | add_unwind_protect (dispose_words, wlist); | |
1396 | add_unwind_protect ((Function *)xfree, word); | |
1397 | ||
1398 | while (clauses) | |
1399 | { | |
1400 | QUIT; | |
1401 | list = clauses->patterns; | |
1402 | while (list) | |
1403 | { | |
1404 | char *pattern; | |
1405 | WORD_LIST *es; | |
1406 | int match; | |
1407 | ||
1408 | /* Posix.2 specifies to tilde expand each member of the pattern | |
1409 | list. */ | |
1410 | if (member ('~', list->word->word)) | |
1411 | { | |
1412 | char *expansion = tilde_expand (list->word->word); | |
1413 | free (list->word->word); | |
1414 | list->word->word = expansion; | |
1415 | } | |
1416 | ||
1417 | es = expand_word_leave_quoted (list->word, 0); | |
1418 | ||
1419 | if (es && es->word && es->word->word && *(es->word->word)) | |
1420 | pattern = quote_string_for_globbing (es->word->word, 1); | |
1421 | else | |
1422 | pattern = savestring (""); | |
1423 | ||
1424 | /* Since the pattern does not undergo quote removal (as per | |
1425 | Posix.2, section 3.9.4.3), the fnmatch () call must be able | |
1426 | to recognize backslashes as escape characters. */ | |
1427 | match = (fnmatch (pattern, word, 0) != FNM_NOMATCH); | |
1428 | free (pattern); | |
1429 | ||
1430 | dispose_words (es); | |
1431 | ||
1432 | if (match) | |
1433 | { | |
1434 | if (clauses->action && | |
1435 | (case_command->flags & CMD_IGNORE_RETURN)) | |
1436 | clauses->action->flags |= CMD_IGNORE_RETURN; | |
1437 | execute_command (clauses->action); | |
1438 | retval = last_command_exit_value; | |
1439 | goto exit_command; | |
1440 | } | |
1441 | ||
1442 | list = list->next; | |
1443 | QUIT; | |
1444 | } | |
1445 | ||
1446 | clauses = clauses->next; | |
1447 | } | |
1448 | ||
1449 | exit_command: | |
1450 | dispose_words (wlist); | |
1451 | free (word); | |
1452 | discard_unwind_frame ("case"); | |
1453 | ||
1454 | return (retval); | |
1455 | } | |
1456 | ||
1457 | #define CMD_WHILE 0 | |
1458 | #define CMD_UNTIL 1 | |
1459 | ||
1460 | /* The WHILE command. Syntax: WHILE test DO action; DONE. | |
1461 | Repeatedly execute action while executing test produces | |
1462 | EXECUTION_SUCCESS. */ | |
1463 | execute_while_command (while_command) | |
1464 | WHILE_COM *while_command; | |
1465 | { | |
1466 | return (execute_while_or_until (while_command, CMD_WHILE)); | |
1467 | } | |
1468 | ||
1469 | /* UNTIL is just like WHILE except that the test result is negated. */ | |
1470 | execute_until_command (while_command) | |
1471 | WHILE_COM *while_command; | |
1472 | { | |
1473 | return (execute_while_or_until (while_command, CMD_UNTIL)); | |
1474 | } | |
1475 | ||
1476 | /* The body for both while and until. The only difference between the | |
1477 | two is that the test value is treated differently. TYPE is | |
1478 | CMD_WHILE or CMD_UNTIL. The return value for both commands should | |
1479 | be EXECUTION_SUCCESS if no commands in the body are executed, and | |
1480 | the status of the last command executed in the body otherwise. */ | |
1481 | execute_while_or_until (while_command, type) | |
1482 | WHILE_COM *while_command; | |
1483 | int type; | |
1484 | { | |
1485 | int return_value, body_status; | |
1486 | ||
1487 | body_status = EXECUTION_SUCCESS; | |
1488 | loop_level++; | |
1489 | ||
1490 | while_command->test->flags |= CMD_IGNORE_RETURN; | |
1491 | if (while_command->flags & CMD_IGNORE_RETURN) | |
1492 | while_command->action->flags |= CMD_IGNORE_RETURN; | |
1493 | ||
1494 | while (1) | |
1495 | { | |
1496 | return_value = execute_command (while_command->test); | |
1497 | REAP (); | |
1498 | ||
1499 | if (type == CMD_WHILE && return_value != EXECUTION_SUCCESS) | |
1500 | break; | |
1501 | if (type == CMD_UNTIL && return_value == EXECUTION_SUCCESS) | |
1502 | break; | |
1503 | ||
1504 | QUIT; | |
1505 | body_status = execute_command (while_command->action); | |
1506 | QUIT; | |
1507 | ||
1508 | if (breaking) | |
1509 | { | |
1510 | breaking--; | |
1511 | break; | |
1512 | } | |
1513 | ||
1514 | if (continuing) | |
1515 | { | |
1516 | continuing--; | |
1517 | if (continuing) | |
1518 | break; | |
1519 | } | |
1520 | } | |
1521 | loop_level--; | |
1522 | ||
1523 | return (body_status); | |
1524 | } | |
1525 | ||
1526 | /* IF test THEN command [ELSE command]. | |
1527 | IF also allows ELIF in the place of ELSE IF, but | |
1528 | the parser makes *that* stupidity transparent. */ | |
1529 | execute_if_command (if_command) | |
1530 | IF_COM *if_command; | |
1531 | { | |
1532 | int return_value; | |
1533 | ||
1534 | if_command->test->flags |= CMD_IGNORE_RETURN; | |
1535 | return_value = execute_command (if_command->test); | |
1536 | ||
1537 | if (return_value == EXECUTION_SUCCESS) | |
1538 | { | |
1539 | QUIT; | |
1540 | if (if_command->true_case && (if_command->flags & CMD_IGNORE_RETURN)) | |
1541 | if_command->true_case->flags |= CMD_IGNORE_RETURN; | |
1542 | return (execute_command (if_command->true_case)); | |
1543 | } | |
1544 | else | |
1545 | { | |
1546 | QUIT; | |
1547 | ||
1548 | if (if_command->false_case && (if_command->flags & CMD_IGNORE_RETURN)) | |
1549 | if_command->false_case->flags |= CMD_IGNORE_RETURN; | |
1550 | ||
1551 | return (execute_command (if_command->false_case)); | |
1552 | } | |
1553 | } | |
1554 | ||
1555 | static void | |
1556 | bind_lastarg (arg) | |
1557 | char *arg; | |
1558 | { | |
1559 | SHELL_VAR *var; | |
1560 | ||
1561 | if (!arg) | |
1562 | arg = ""; | |
1563 | var = bind_variable ("_", arg); | |
1564 | var->attributes &= ~att_exported; | |
1565 | } | |
1566 | ||
1567 | /* The meaty part of all the executions. We have to start hacking the | |
1568 | real execution of commands here. Fork a process, set things up, | |
1569 | execute the command. */ | |
1570 | execute_simple_command (simple_command, pipe_in, pipe_out, async, fds_to_close) | |
1571 | SIMPLE_COM *simple_command; | |
1572 | int pipe_in, pipe_out, async; | |
1573 | struct fd_bitmap *fds_to_close; | |
1574 | { | |
1575 | WORD_LIST *words, *lastword; | |
1576 | char *command_line, *lastarg; | |
1577 | int first_word_quoted, result; | |
1578 | pid_t old_last_command_subst_pid; | |
1579 | ||
1580 | result = EXECUTION_SUCCESS; | |
1581 | ||
1582 | /* If we're in a function, update the pseudo-line-number information. */ | |
1583 | if (variable_context) | |
1584 | line_number = simple_command->line - function_line_number; | |
1585 | ||
1586 | /* Remember what this command line looks like at invocation. */ | |
1587 | command_string_index = 0; | |
1588 | print_simple_command (simple_command); | |
1589 | command_line = (char *)alloca (1 + strlen (the_printed_command)); | |
1590 | strcpy (command_line, the_printed_command); | |
1591 | ||
1592 | first_word_quoted = | |
1593 | simple_command->words ? simple_command->words->word->quoted : 0; | |
1594 | ||
1595 | old_last_command_subst_pid = last_command_subst_pid; | |
1596 | ||
1597 | /* If we are re-running this as the result of executing the `command' | |
1598 | builtin, do not expand the command words a second time. */ | |
1599 | if ((simple_command->flags & CMD_INHIBIT_EXPANSION) == 0) | |
1600 | { | |
1601 | current_fds_to_close = fds_to_close; | |
1602 | words = expand_words (simple_command->words); | |
1603 | current_fds_to_close = (struct fd_bitmap *)NULL; | |
1604 | } | |
1605 | else | |
1606 | words = copy_word_list (simple_command->words); | |
1607 | ||
1608 | lastarg = (char *)NULL; | |
1609 | ||
1610 | /* It is possible for WORDS not to have anything left in it. | |
1611 | Perhaps all the words consisted of `$foo', and there was | |
1612 | no variable `$foo'. */ | |
1613 | if (words) | |
1614 | { | |
1615 | Function *builtin; | |
1616 | SHELL_VAR *func; | |
1617 | ||
1618 | begin_unwind_frame ("simple-command"); | |
1619 | ||
1620 | if (echo_command_at_execute) | |
1621 | { | |
1622 | char *line = string_list (words); | |
1623 | ||
1624 | if (line && *line) | |
1625 | fprintf (stderr, "%s%s\n", indirection_level_string (), line); | |
1626 | ||
1627 | FREE (line); | |
1628 | } | |
1629 | ||
1630 | if (simple_command->flags & CMD_NO_FUNCTIONS) | |
1631 | func = (SHELL_VAR *)NULL; | |
1632 | else | |
1633 | func = find_function (words->word->word); | |
1634 | ||
1635 | add_unwind_protect (dispose_words, words); | |
1636 | ||
1637 | QUIT; | |
1638 | ||
1639 | /* Bind the last word in this command to "$_" after execution. */ | |
1640 | for (lastword = words; lastword->next; lastword = lastword->next); | |
1641 | lastarg = lastword->word->word; | |
1642 | ||
1643 | #if defined (JOB_CONTROL) | |
1644 | /* Is this command a job control related thing? */ | |
1645 | if (words->word->word[0] == '%') | |
1646 | { | |
1647 | int result; | |
1648 | ||
1649 | if (async) | |
1650 | this_command_name = "bg"; | |
1651 | else | |
1652 | this_command_name = "fg"; | |
1653 | ||
1654 | last_shell_builtin = this_shell_builtin; | |
1655 | this_shell_builtin = builtin_address (this_command_name); | |
1656 | result = (*this_shell_builtin) (words); | |
1657 | goto return_result; | |
1658 | } | |
1659 | ||
1660 | /* One other possiblilty. The user may want to resume an existing job. | |
1661 | If they do, find out whether this word is a candidate for a running | |
1662 | job. */ | |
1663 | { | |
1664 | char *auto_resume_value = get_string_value ("auto_resume"); | |
1665 | ||
1666 | if (auto_resume_value && | |
1667 | !first_word_quoted && | |
1668 | !words->next && | |
1669 | words->word->word[0] && | |
1670 | !simple_command->redirects && | |
1671 | pipe_in == NO_PIPE && | |
1672 | pipe_out == NO_PIPE && | |
1673 | !async) | |
1674 | { | |
1675 | char *word = words->word->word; | |
1676 | register int i; | |
1677 | int wl, cl, exact, substring, match, started_status; | |
1678 | register PROCESS *p; | |
1679 | ||
1680 | exact = STREQ (auto_resume_value, "exact"); | |
1681 | substring = STREQ (auto_resume_value, "substring"); | |
1682 | wl = strlen (word); | |
1683 | for (i = job_slots - 1; i > -1; i--) | |
1684 | { | |
1685 | if (!jobs[i] || (JOBSTATE (i) != JSTOPPED)) | |
1686 | continue; | |
1687 | ||
1688 | p = jobs[i]->pipe; | |
1689 | do | |
1690 | { | |
1691 | if (exact) | |
1692 | { | |
1693 | cl = strlen (p->command); | |
1694 | match = STREQN (p->command, word, cl); | |
1695 | } | |
1696 | else if (substring) | |
1697 | match = strindex (p->command, word) != (char *)0; | |
1698 | else | |
1699 | match = STREQN (p->command, word, wl); | |
1700 | ||
1701 | if (match == 0) | |
1702 | { | |
1703 | p = p->next; | |
1704 | continue; | |
1705 | } | |
1706 | ||
1707 | run_unwind_frame ("simple-command"); | |
1708 | last_shell_builtin = this_shell_builtin; | |
1709 | this_shell_builtin = builtin_address ("fg"); | |
1710 | ||
1711 | started_status = start_job (i, 1); | |
1712 | ||
1713 | if (started_status < 0) | |
1714 | return (EXECUTION_FAILURE); | |
1715 | else | |
1716 | return (started_status); | |
1717 | } | |
1718 | while (p != jobs[i]->pipe); | |
1719 | } | |
1720 | } | |
1721 | } | |
1722 | #endif /* JOB_CONTROL */ | |
1723 | ||
1724 | /* Remember the name of this command globally. */ | |
1725 | this_command_name = words->word->word; | |
1726 | ||
1727 | QUIT; | |
1728 | ||
1729 | /* This command could be a shell builtin or a user-defined function. | |
1730 | If so, and we have pipes, then fork a subshell in here. Else, just | |
1731 | do the command. */ | |
1732 | ||
1733 | if (func) | |
1734 | builtin = (Function *)NULL; | |
1735 | else | |
1736 | builtin = find_shell_builtin (this_command_name); | |
1737 | ||
1738 | last_shell_builtin = this_shell_builtin; | |
1739 | this_shell_builtin = builtin; | |
1740 | ||
1741 | if (builtin || func) | |
1742 | { | |
1743 | if ((pipe_in != NO_PIPE) || (pipe_out != NO_PIPE) || async) | |
1744 | { | |
1745 | if (make_child (savestring (command_line), async) == 0) | |
1746 | { | |
1747 | /* Cancel traps, in trap.c. */ | |
1748 | restore_original_signals (); | |
1749 | ||
1750 | if (async) | |
1751 | setup_async_signals (); | |
1752 | ||
1753 | execute_subshell_builtin_or_function | |
1754 | (words, simple_command->redirects, builtin, func, | |
1755 | pipe_in, pipe_out, async, fds_to_close, | |
1756 | simple_command->flags); | |
1757 | } | |
1758 | else | |
1759 | { | |
1760 | close_pipes (pipe_in, pipe_out); | |
1761 | #if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD) | |
1762 | unlink_fifo_list (); | |
1763 | #endif | |
1764 | goto return_result; | |
1765 | } | |
1766 | } | |
1767 | else | |
1768 | { | |
1769 | result = execute_builtin_or_function | |
1770 | (words, builtin, func, simple_command->redirects, fds_to_close, | |
1771 | simple_command->flags); | |
1772 | ||
1773 | goto return_result; | |
1774 | } | |
1775 | } | |
1776 | ||
1777 | execute_disk_command (words, simple_command->redirects, command_line, | |
1778 | pipe_in, pipe_out, async, fds_to_close, | |
1779 | (simple_command->flags & CMD_NO_FORK)); | |
1780 | ||
1781 | goto return_result; | |
1782 | } | |
1783 | else if (pipe_in != NO_PIPE || pipe_out != NO_PIPE || async) | |
1784 | { | |
1785 | /* We have a null command, but we really want a subshell to take | |
1786 | care of it. Just fork, do piping and redirections, and exit. */ | |
1787 | if (make_child (savestring (""), async) == 0) | |
1788 | { | |
1789 | /* Cancel traps, in trap.c. */ | |
1790 | restore_original_signals (); | |
1791 | ||
1792 | do_piping (pipe_in, pipe_out); | |
1793 | ||
1794 | subshell_environment = 1; | |
1795 | ||
1796 | if (do_redirections (simple_command->redirects, 1, 0, 0) == 0) | |
1797 | exit (EXECUTION_SUCCESS); | |
1798 | else | |
1799 | exit (EXECUTION_FAILURE); | |
1800 | } | |
1801 | else | |
1802 | { | |
1803 | close_pipes (pipe_in, pipe_out); | |
1804 | #if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD) | |
1805 | unlink_fifo_list (); | |
1806 | #endif | |
1807 | result = EXECUTION_SUCCESS; | |
1808 | goto return_result; | |
1809 | } | |
1810 | } | |
1811 | else | |
1812 | { | |
1813 | /* Even if there aren't any command names, pretend to do the | |
1814 | redirections that are specified. The user expects the side | |
1815 | effects to take place. If the redirections fail, then return | |
1816 | failure. Otherwise, if a command substitution took place while | |
1817 | expanding the command or a redirection, return the value of that | |
1818 | substitution. Otherwise, return EXECUTION_SUCCESS. */ | |
1819 | ||
1820 | if (do_redirections (simple_command->redirects, 0, 0, 0) != 0) | |
1821 | result = EXECUTION_FAILURE; | |
1822 | else if (old_last_command_subst_pid != last_command_subst_pid) | |
1823 | result = last_command_exit_value; | |
1824 | else | |
1825 | result = EXECUTION_SUCCESS; | |
1826 | } | |
1827 | ||
1828 | return_result: | |
1829 | bind_lastarg (lastarg); | |
1830 | /* The unwind-protect frame is set up only if WORDS is not empty. */ | |
1831 | if (words) | |
1832 | run_unwind_frame ("simple-command"); | |
1833 | return (result); | |
1834 | } | |
1835 | ||
1836 | static int | |
1837 | execute_builtin (builtin, words, flags, subshell) | |
1838 | Function *builtin; | |
1839 | WORD_LIST *words; | |
1840 | int flags, subshell; | |
1841 | { | |
1842 | int old_e_flag = exit_immediately_on_error; | |
1843 | int result; | |
1844 | ||
1845 | /* The eval builtin calls parse_and_execute, which does not know about | |
1846 | the setting of flags, and always calls the execution functions with | |
1847 | flags that will exit the shell on an error if -e is set. If the | |
1848 | eval builtin is being called, and we're supposed to ignore the exit | |
1849 | value of the command, we turn the -e flag off ourselves, then | |
1850 | restore it when the command completes. */ | |
1851 | if (subshell == 0 && builtin == eval_builtin && (flags & CMD_IGNORE_RETURN)) | |
1852 | { | |
1853 | begin_unwind_frame ("eval_builtin"); | |
1854 | unwind_protect_int (exit_immediately_on_error); | |
1855 | exit_immediately_on_error = 0; | |
1856 | } | |
1857 | ||
1858 | /* The temporary environment for a builtin is supposed to apply to | |
1859 | all commands executed by that builtin. Currently, this is a | |
1860 | problem only with the `source' builtin. */ | |
1861 | if (builtin == source_builtin) | |
1862 | { | |
1863 | if (subshell == 0) | |
1864 | begin_unwind_frame ("builtin_env"); | |
1865 | ||
1866 | if (temporary_env) | |
1867 | { | |
1868 | builtin_env = copy_array (temporary_env); | |
1869 | if (subshell == 0) | |
1870 | add_unwind_protect (dispose_builtin_env, (char *)NULL); | |
1871 | dispose_used_env_vars (); | |
1872 | } | |
1873 | #if 0 | |
1874 | else | |
1875 | builtin_env = (char **)NULL; | |
1876 | #endif | |
1877 | } | |
1878 | ||
1879 | result = ((*builtin) (words->next)); | |
1880 | ||
1881 | if (subshell == 0 && builtin == source_builtin) | |
1882 | { | |
1883 | dispose_builtin_env (); | |
1884 | discard_unwind_frame ("builtin_env"); | |
1885 | } | |
1886 | ||
1887 | if (subshell == 0 && builtin == eval_builtin && (flags & CMD_IGNORE_RETURN)) | |
1888 | { | |
1889 | exit_immediately_on_error += old_e_flag; | |
1890 | discard_unwind_frame ("eval_builtin"); | |
1891 | } | |
1892 | ||
1893 | return (result); | |
1894 | } | |
1895 | ||
1896 | /* XXX -- why do we need to set up unwind-protects for the case where | |
1897 | subshell == 1 at all? */ | |
1898 | static int | |
1899 | execute_function (var, words, flags, fds_to_close, async, subshell) | |
1900 | SHELL_VAR *var; | |
1901 | WORD_LIST *words; | |
1902 | int flags, subshell, async; | |
1903 | struct fd_bitmap *fds_to_close; | |
1904 | { | |
1905 | int return_val, result; | |
1906 | COMMAND *tc, *fc; | |
1907 | ||
1908 | tc = (COMMAND *)copy_command (function_cell (var)); | |
1909 | if (tc && (flags & CMD_IGNORE_RETURN)) | |
1910 | tc->flags |= CMD_IGNORE_RETURN; | |
1911 | ||
1912 | if (subshell) | |
1913 | begin_unwind_frame ("subshell_function_calling"); | |
1914 | else | |
1915 | begin_unwind_frame ("function_calling"); | |
1916 | ||
1917 | if (subshell == 0) | |
1918 | { | |
1919 | push_context (); | |
1920 | add_unwind_protect (pop_context, (char *)NULL); | |
1921 | unwind_protect_int (line_number); | |
1922 | } | |
1923 | else | |
1924 | unwind_protect_int (variable_context); | |
1925 | ||
1926 | unwind_protect_int (loop_level); | |
1927 | unwind_protect_int (return_catch_flag); | |
1928 | unwind_protect_jmp_buf (return_catch); | |
1929 | add_unwind_protect (dispose_command, (char *)tc); | |
1930 | ||
1931 | /* The temporary environment for a function is supposed to apply to | |
1932 | all commands executed within the function body. */ | |
1933 | if (temporary_env) | |
1934 | { | |
1935 | function_env = copy_array (temporary_env); | |
1936 | add_unwind_protect (dispose_function_env, (char *)NULL); | |
1937 | dispose_used_env_vars (); | |
1938 | } | |
1939 | #if 0 | |
1940 | else | |
1941 | function_env = (char **)NULL; | |
1942 | #endif | |
1943 | ||
1944 | /* Note the second argument of "1", meaning that we discard | |
1945 | the current value of "$*"! This is apparently the right thing. */ | |
1946 | remember_args (words->next, 1); | |
1947 | ||
1948 | line_number = function_line_number = tc->line; | |
1949 | ||
1950 | if (subshell) | |
1951 | { | |
1952 | #if defined (JOB_CONTROL) | |
1953 | stop_pipeline (async, (COMMAND *)NULL); | |
1954 | #endif | |
1955 | if (tc->type == cm_group) | |
1956 | fc = tc->value.Group->command; | |
1957 | else | |
1958 | fc = tc; | |
1959 | ||
1960 | if (fc && (flags & CMD_IGNORE_RETURN)) | |
1961 | fc->flags |= CMD_IGNORE_RETURN; | |
1962 | ||
1963 | variable_context++; | |
1964 | } | |
1965 | else | |
1966 | fc = tc; | |
1967 | ||
1968 | return_catch_flag++; | |
1969 | return_val = setjmp (return_catch); | |
1970 | ||
1971 | if (return_val) | |
1972 | result = return_catch_value; | |
1973 | else | |
1974 | result = execute_command_internal (fc, 0, NO_PIPE, NO_PIPE, fds_to_close); | |
1975 | ||
1976 | if (subshell) | |
1977 | run_unwind_frame ("subshell_function_calling"); | |
1978 | else | |
1979 | run_unwind_frame ("function_calling"); | |
1980 | ||
1981 | return (result); | |
1982 | } | |
1983 | ||
1984 | /* Execute a shell builtin or function in a subshell environment. This | |
1985 | routine does not return; it only calls exit(). If BUILTIN is non-null, | |
1986 | it points to a function to call to execute a shell builtin; otherwise | |
1987 | VAR points at the body of a function to execute. WORDS is the arguments | |
1988 | to the command, REDIRECTS specifies redirections to perform before the | |
1989 | command is executed. */ | |
1990 | static void | |
1991 | execute_subshell_builtin_or_function (words, redirects, builtin, var, | |
1992 | pipe_in, pipe_out, async, fds_to_close, | |
1993 | flags) | |
1994 | WORD_LIST *words; | |
1995 | REDIRECT *redirects; | |
1996 | Function *builtin; | |
1997 | SHELL_VAR *var; | |
1998 | int pipe_in, pipe_out, async; | |
1999 | struct fd_bitmap *fds_to_close; | |
2000 | int flags; | |
2001 | { | |
2002 | /* A subshell is neither a login shell nor interactive. */ | |
2003 | login_shell = interactive = 0; | |
2004 | ||
2005 | subshell_environment = 1; | |
2006 | ||
2007 | maybe_make_export_env (); | |
2008 | ||
2009 | #if defined (JOB_CONTROL) | |
2010 | /* Eradicate all traces of job control after we fork the subshell, so | |
2011 | all jobs begun by this subshell are in the same process group as | |
2012 | the shell itself. */ | |
2013 | ||
2014 | /* Allow the output of `jobs' to be piped. */ | |
2015 | if (builtin == jobs_builtin && !async && | |
2016 | (pipe_out != NO_PIPE || pipe_in != NO_PIPE)) | |
2017 | kill_current_pipeline (); | |
2018 | else | |
2019 | without_job_control (); | |
2020 | ||
2021 | set_sigchld_handler (); | |
2022 | #endif /* JOB_CONTROL */ | |
2023 | ||
2024 | set_sigint_handler (); | |
2025 | ||
2026 | do_piping (pipe_in, pipe_out); | |
2027 | ||
2028 | if (fds_to_close) | |
2029 | close_fd_bitmap (fds_to_close); | |
2030 | ||
2031 | if (do_redirections (redirects, 1, 0, 0) != 0) | |
2032 | exit (EXECUTION_FAILURE); | |
2033 | ||
2034 | if (builtin) | |
2035 | { | |
2036 | int result; | |
2037 | ||
2038 | /* Give builtins a place to jump back to on failure, | |
2039 | so we don't go back up to main(). */ | |
2040 | result = setjmp (top_level); | |
2041 | ||
2042 | if (result == EXITPROG) | |
2043 | exit (last_command_exit_value); | |
2044 | else if (result) | |
2045 | exit (EXECUTION_FAILURE); | |
2046 | else | |
2047 | exit (execute_builtin (builtin, words, flags, 1)); | |
2048 | } | |
2049 | else | |
2050 | { | |
2051 | exit (execute_function (var, words, flags, fds_to_close, async, 1)); | |
2052 | } | |
2053 | } | |
2054 | ||
2055 | /* Execute a builtin or function in the current shell context. If BUILTIN | |
2056 | is non-null, it is the builtin command to execute, otherwise VAR points | |
2057 | to the body of a function. WORDS are the command's arguments, REDIRECTS | |
2058 | are the redirections to perform. FDS_TO_CLOSE is the usual bitmap of | |
2059 | file descriptors to close. | |
2060 | ||
2061 | If BUILTIN is exec_builtin, the redirections specified in REDIRECTS are | |
2062 | not undone before this function returns. */ | |
2063 | static int | |
2064 | execute_builtin_or_function (words, builtin, var, redirects, | |
2065 | fds_to_close, flags) | |
2066 | WORD_LIST *words; | |
2067 | Function *builtin; | |
2068 | SHELL_VAR *var; | |
2069 | REDIRECT *redirects; | |
2070 | struct fd_bitmap *fds_to_close; | |
2071 | int flags; | |
2072 | { | |
2073 | int result = EXECUTION_FAILURE; | |
2074 | REDIRECT *saved_undo_list; | |
2075 | ||
2076 | if (do_redirections (redirects, 1, 1, 0) != 0) | |
2077 | { | |
2078 | cleanup_redirects (redirection_undo_list); | |
2079 | redirection_undo_list = (REDIRECT *)NULL; | |
2080 | dispose_exec_redirects (); | |
2081 | return (EXECUTION_FAILURE); | |
2082 | } | |
2083 | ||
2084 | saved_undo_list = redirection_undo_list; | |
2085 | ||
2086 | /* Calling the "exec" builtin changes redirections forever. */ | |
2087 | if (builtin == exec_builtin) | |
2088 | { | |
2089 | dispose_redirects (saved_undo_list); | |
2090 | saved_undo_list = exec_redirection_undo_list; | |
2091 | exec_redirection_undo_list = (REDIRECT *)NULL; | |
2092 | } | |
2093 | else | |
2094 | dispose_exec_redirects (); | |
2095 | ||
2096 | if (saved_undo_list) | |
2097 | { | |
2098 | begin_unwind_frame ("saved redirects"); | |
2099 | add_unwind_protect (cleanup_func_redirects, (char *)saved_undo_list); | |
2100 | add_unwind_protect (dispose_redirects, (char *)saved_undo_list); | |
2101 | } | |
2102 | ||
2103 | redirection_undo_list = (REDIRECT *)NULL; | |
2104 | ||
2105 | if (builtin) | |
2106 | result = execute_builtin (builtin, words, flags, 0); | |
2107 | else | |
2108 | result = execute_function (var, words, flags, fds_to_close, 0, 0); | |
2109 | ||
2110 | if (saved_undo_list) | |
2111 | { | |
2112 | redirection_undo_list = saved_undo_list; | |
2113 | discard_unwind_frame ("saved redirects"); | |
2114 | } | |
2115 | ||
2116 | if (redirection_undo_list) | |
2117 | { | |
2118 | do_redirections (redirection_undo_list, 1, 0, 0); | |
2119 | dispose_redirects (redirection_undo_list); | |
2120 | redirection_undo_list = (REDIRECT *)NULL; | |
2121 | } | |
2122 | ||
2123 | return (result); | |
2124 | } | |
2125 | ||
2126 | void | |
2127 | setup_async_signals () | |
2128 | { | |
2129 | #if defined (JOB_CONTROL) | |
2130 | if (job_control == 0) | |
2131 | #endif | |
2132 | { | |
2133 | set_signal_handler (SIGINT, SIG_IGN); | |
2134 | set_signal_ignored (SIGINT); | |
2135 | set_signal_handler (SIGQUIT, SIG_IGN); | |
2136 | set_signal_ignored (SIGQUIT); | |
2137 | } | |
2138 | } | |
2139 | ||
2140 | /* Execute a simple command that is hopefully defined in a disk file | |
2141 | somewhere. | |
2142 | ||
2143 | 1) fork () | |
2144 | 2) connect pipes | |
2145 | 3) look up the command | |
2146 | 4) do redirections | |
2147 | 5) execve () | |
2148 | 6) If the execve failed, see if the file has executable mode set. | |
2149 | If so, and it isn't a directory, then execute its contents as | |
2150 | a shell script. | |
2151 | ||
2152 | Note that the filename hashing stuff has to take place up here, | |
2153 | in the parent. This is probably why the Bourne style shells | |
2154 | don't handle it, since that would require them to go through | |
2155 | this gnarly hair, for no good reason. */ | |
2156 | static void | |
2157 | execute_disk_command (words, redirects, command_line, pipe_in, pipe_out, | |
2158 | async, fds_to_close, nofork) | |
2159 | WORD_LIST *words; | |
2160 | REDIRECT *redirects; | |
2161 | char *command_line; | |
2162 | int pipe_in, pipe_out, async; | |
2163 | struct fd_bitmap *fds_to_close; | |
2164 | int nofork; /* Don't fork, just exec, if no pipes */ | |
2165 | { | |
2166 | register char *pathname; | |
2167 | char *hashed_file, *command, **args; | |
2168 | int pid, temp_path; | |
2169 | SHELL_VAR *path; | |
2170 | ||
2171 | pathname = words->word->word; | |
2172 | #if defined (RESTRICTED_SHELL) | |
2173 | if (restricted && strchr (pathname, '/')) | |
2174 | { | |
2175 | report_error ("%s: restricted: cannot specify `/' in command names", | |
2176 | pathname); | |
2177 | last_command_exit_value = EXECUTION_FAILURE; | |
2178 | return; | |
2179 | } | |
2180 | #endif /* RESTRICTED_SHELL */ | |
2181 | ||
2182 | hashed_file = command = (char *)NULL; | |
2183 | ||
2184 | /* If PATH is in the temporary environment for this command, don't use the | |
2185 | hash table to search for the full pathname. */ | |
2186 | temp_path = 0; | |
2187 | path = find_tempenv_variable ("PATH"); | |
2188 | if (path) | |
2189 | temp_path = 1; | |
2190 | ||
2191 | /* Don't waste time trying to find hashed data for a pathname | |
2192 | that is already completely specified. */ | |
2193 | ||
2194 | if (!path && !absolute_program (pathname)) | |
2195 | hashed_file = find_hashed_filename (pathname); | |
2196 | ||
2197 | /* If a command found in the hash table no longer exists, we need to | |
2198 | look for it in $PATH. Thank you Posix.2. This forces us to stat | |
2199 | every command found in the hash table. It seems pretty stupid to me, | |
2200 | so I am basing it on the presence of POSIXLY_CORRECT. */ | |
2201 | ||
2202 | if (hashed_file && posixly_correct) | |
2203 | { | |
2204 | int st; | |
2205 | ||
2206 | st = file_status (hashed_file); | |
2207 | if ((st ^ (FS_EXISTS | FS_EXECABLE)) != 0) | |
2208 | { | |
2209 | remove_hashed_filename (pathname); | |
2210 | hashed_file = (char *)NULL; | |
2211 | } | |
2212 | } | |
2213 | ||
2214 | if (hashed_file) | |
2215 | command = savestring (hashed_file); | |
2216 | else if (absolute_program (pathname)) | |
2217 | /* A command containing a slash is not looked up in PATH or saved in | |
2218 | the hash table. */ | |
2219 | command = savestring (pathname); | |
2220 | else | |
2221 | { | |
2222 | command = find_user_command (pathname); | |
2223 | if (command && !hashing_disabled && !temp_path) | |
2224 | remember_filename (pathname, command, dot_found_in_search, 1); | |
2225 | } | |
2226 | ||
2227 | maybe_make_export_env (); | |
2228 | ||
2229 | if (command) | |
2230 | put_command_name_into_env (command); | |
2231 | ||
2232 | /* We have to make the child before we check for the non-existance | |
2233 | of COMMAND, since we want the error messages to be redirected. */ | |
2234 | /* If we can get away without forking and there are no pipes to deal with, | |
2235 | don't bother to fork, just directly exec the command. */ | |
2236 | if (nofork && pipe_in == NO_PIPE && pipe_out == NO_PIPE) | |
2237 | pid = 0; | |
2238 | else | |
2239 | pid = make_child (savestring (command_line), async); | |
2240 | ||
2241 | if (pid == 0) | |
2242 | { | |
2243 | int old_interactive; | |
2244 | ||
2245 | /* Cancel traps, in trap.c. */ | |
2246 | restore_original_signals (); | |
2247 | ||
2248 | /* restore_original_signals may have undone the work done | |
2249 | by make_child to ensure that SIGINT and SIGQUIT are ignored | |
2250 | in asynchronous children. */ | |
2251 | if (async) | |
2252 | setup_async_signals (); | |
2253 | ||
2254 | do_piping (pipe_in, pipe_out); | |
2255 | ||
2256 | /* Execve expects the command name to be in args[0]. So we | |
2257 | leave it there, in the same format that the user used to | |
2258 | type it in. */ | |
2259 | args = make_word_array (words); | |
2260 | ||
2261 | if (async) | |
2262 | { | |
2263 | old_interactive = interactive; | |
2264 | interactive = 0; | |
2265 | } | |
2266 | ||
2267 | subshell_environment = 1; | |
2268 | ||
2269 | /* This functionality is now provided by close-on-exec of the | |
2270 | file descriptors manipulated by redirection and piping. | |
2271 | Some file descriptors still need to be closed in all children | |
2272 | because of the way bash does pipes; fds_to_close is a | |
2273 | bitmap of all such file descriptors. */ | |
2274 | if (fds_to_close) | |
2275 | close_fd_bitmap (fds_to_close); | |
2276 | ||
2277 | if (redirects && (do_redirections (redirects, 1, 0, 0) != 0)) | |
2278 | { | |
2279 | #if defined (PROCESS_SUBSTITUTION) | |
2280 | /* Try to remove named pipes that may have been created as the | |
2281 | result of redirections. */ | |
2282 | unlink_fifo_list (); | |
2283 | #endif /* PROCESS_SUBSTITUTION */ | |
2284 | exit (EXECUTION_FAILURE); | |
2285 | } | |
2286 | ||
2287 | if (async) | |
2288 | interactive = old_interactive; | |
2289 | ||
2290 | if (!command) | |
2291 | { | |
2292 | report_error ("%s: command not found", args[0]); | |
2293 | exit (EX_NOTFOUND); /* Posix.2 says the exit status is 127 */ | |
2294 | } | |
2295 | ||
2296 | exit (shell_execve (command, args, export_env)); | |
2297 | } | |
2298 | else | |
2299 | { | |
2300 | /* Make sure that the pipes are closed in the parent. */ | |
2301 | close_pipes (pipe_in, pipe_out); | |
2302 | #if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD) | |
2303 | unlink_fifo_list (); | |
2304 | #endif | |
2305 | FREE (command); | |
2306 | } | |
2307 | } | |
2308 | ||
2309 | /* If the operating system on which we're running does not handle | |
2310 | the #! executable format, then help out. SAMPLE is the text read | |
2311 | from the file, SAMPLE_LEN characters. COMMAND is the name of | |
2312 | the script; it and ARGS, the arguments given by the user, will | |
2313 | become arguments to the specified interpreter. ENV is the environment | |
2314 | to pass to the interpreter. | |
2315 | ||
2316 | The word immediately following the #! is the interpreter to execute. | |
2317 | A single argument to the interpreter is allowed. */ | |
2318 | static int | |
2319 | execute_shell_script (sample, sample_len, command, args, env) | |
2320 | unsigned char *sample; | |
2321 | int sample_len; | |
2322 | char *command; | |
2323 | char **args, **env; | |
2324 | { | |
2325 | register int i; | |
2326 | char *execname, *firstarg; | |
2327 | int start, size_increment, larry; | |
2328 | ||
2329 | /* Find the name of the interpreter to exec. */ | |
2330 | for (i = 2; whitespace (sample[i]) && i < sample_len; i++) | |
2331 | ; | |
2332 | ||
2333 | for (start = i; | |
2334 | !whitespace (sample[i]) && sample[i] != '\n' && i < sample_len; | |
2335 | i++) | |
2336 | ; | |
2337 | ||
2338 | execname = xmalloc (1 + (i - start)); | |
2339 | strncpy (execname, (char *) (sample + start), i - start); | |
2340 | execname[i - start] = '\0'; | |
2341 | size_increment = 1; | |
2342 | ||
2343 | /* Now the argument, if any. */ | |
2344 | firstarg = (char *)NULL; | |
2345 | for (start = i; | |
2346 | whitespace (sample[i]) && sample[i] != '\n' && i < sample_len; | |
2347 | i++) | |
2348 | ; | |
2349 | ||
2350 | /* If there is more text on the line, then it is an argument for the | |
2351 | interpreter. */ | |
2352 | if (i < sample_len && sample[i] != '\n' && !whitespace (sample[i])) | |
2353 | { | |
2354 | for (start = i; | |
2355 | !whitespace (sample[i]) && sample[i] != '\n' && i < sample_len; | |
2356 | i++) | |
2357 | ; | |
2358 | firstarg = xmalloc (1 + (i - start)); | |
2359 | strncpy (firstarg, (char *)(sample + start), i - start); | |
2360 | firstarg[i - start] = '\0'; | |
2361 | ||
2362 | size_increment = 2; | |
2363 | } | |
2364 | ||
2365 | larry = array_len (args) + size_increment; | |
2366 | ||
2367 | args = (char **)xrealloc ((char *)args, (1 + larry) * sizeof (char *)); | |
2368 | ||
2369 | for (i = larry - 1; i; i--) | |
2370 | args[i] = args[i - size_increment]; | |
2371 | ||
2372 | args[0] = execname; | |
2373 | if (firstarg) | |
2374 | { | |
2375 | args[1] = firstarg; | |
2376 | args[2] = command; | |
2377 | } | |
2378 | else | |
2379 | args[1] = command; | |
2380 | ||
2381 | args[larry] = (char *)NULL; | |
2382 | ||
2383 | return (shell_execve (execname, args, env)); | |
2384 | } | |
2385 | ||
2386 | /* Call execve (), handling interpreting shell scripts, and handling | |
2387 | exec failures. */ | |
2388 | int | |
2389 | shell_execve (command, args, env) | |
2390 | char *command; | |
2391 | char **args, **env; | |
2392 | { | |
2393 | #if defined (isc386) && defined (_POSIX_SOURCE) | |
2394 | __setostype (0); /* Turn on USGr3 semantics. */ | |
2395 | execve (command, args, env); | |
2396 | __setostype (1); /* Turn the POSIX semantics back on. */ | |
2397 | #else | |
2398 | execve (command, args, env); | |
2399 | #endif /* !(isc386 && _POSIX_SOURCE) */ | |
2400 | ||
2401 | /* If we get to this point, then start checking out the file. | |
2402 | Maybe it is something we can hack ourselves. */ | |
2403 | { | |
2404 | struct stat finfo; | |
2405 | ||
2406 | if (errno != ENOEXEC) | |
2407 | { | |
2408 | if ((stat (command, &finfo) == 0) && | |
2409 | (S_ISDIR (finfo.st_mode))) | |
2410 | report_error ("%s: is a directory", args[0]); | |
2411 | else | |
2412 | file_error (command); | |
2413 | ||
2414 | return (EX_NOEXEC); /* XXX Posix.2 says that exit status is 126 */ | |
2415 | } | |
2416 | else | |
2417 | { | |
2418 | /* This file is executable. | |
2419 | If it begins with #!, then help out people with losing operating | |
2420 | systems. Otherwise, check to see if it is a binary file by seeing | |
2421 | if the first line (or up to 30 characters) are in the ASCII set. | |
2422 | Execute the contents as shell commands. */ | |
2423 | int larray = array_len (args) + 1; | |
2424 | int i, should_exec = 0; | |
2425 | ||
2426 | { | |
2427 | int fd = open (command, O_RDONLY); | |
2428 | if (fd != -1) | |
2429 | { | |
2430 | unsigned char sample[80]; | |
2431 | int sample_len = read (fd, &sample[0], 80); | |
2432 | ||
2433 | close (fd); | |
2434 | ||
2435 | if (sample_len == 0) | |
2436 | return (EXECUTION_SUCCESS); | |
2437 | ||
2438 | /* Is this supposed to be an executable script? | |
2439 | If so, the format of the line is "#! interpreter [argument]". | |
2440 | A single argument is allowed. The BSD kernel restricts | |
2441 | the length of the entire line to 32 characters (32 bytes | |
2442 | being the size of the BSD exec header), but we allow 80 | |
2443 | characters. */ | |
2444 | ||
2445 | if (sample_len > 0 && sample[0] == '#' && sample[1] == '!') | |
2446 | return (execute_shell_script | |
2447 | (sample, sample_len, command, args, env)); | |
2448 | else if ((sample_len != -1) && | |
2449 | check_binary_file (sample, sample_len)) | |
2450 | { | |
2451 | report_error ("%s: cannot execute binary file", command); | |
2452 | return (EX_BINARY_FILE); | |
2453 | } | |
2454 | } | |
2455 | } | |
2456 | #if defined (JOB_CONTROL) | |
2457 | /* Forget about the way that job control was working. We are | |
2458 | in a subshell. */ | |
2459 | without_job_control (); | |
2460 | #endif /* JOB_CONTROL */ | |
2461 | #if defined (ALIAS) | |
2462 | /* Forget about any aliases that we knew of. We are in a subshell. */ | |
2463 | delete_all_aliases (); | |
2464 | #endif /* ALIAS */ | |
2465 | ||
2466 | #if defined (JOB_CONTROL) | |
2467 | set_sigchld_handler (); | |
2468 | #endif /* JOB_CONTROL */ | |
2469 | set_sigint_handler (); | |
2470 | ||
2471 | /* Insert the name of this shell into the argument list. */ | |
2472 | args = (char **)xrealloc ((char *)args, (1 + larray) * sizeof (char *)); | |
2473 | ||
2474 | for (i = larray - 1; i; i--) | |
2475 | args[i] = args[i - 1]; | |
2476 | ||
2477 | args[0] = shell_name; | |
2478 | args[1] = command; | |
2479 | args[larray] = (char *)NULL; | |
2480 | ||
2481 | if (args[0][0] == '-') | |
2482 | args[0]++; | |
2483 | ||
2484 | if (should_exec) | |
2485 | { | |
2486 | struct stat finfo; | |
2487 | ||
2488 | #if defined (isc386) && defined (_POSIX_SOURCE) | |
2489 | __setostype (0); /* Turn on USGr3 semantics. */ | |
2490 | execve (shell_name, args, env); | |
2491 | __setostype (1); /* Turn the POSIX semantics back on. */ | |
2492 | #else | |
2493 | execve (shell_name, args, env); | |
2494 | #endif /* isc386 && _POSIX_SOURCE */ | |
2495 | ||
2496 | /* Oh, no! We couldn't even exec this! */ | |
2497 | if ((stat (args[0], &finfo) == 0) && (S_ISDIR (finfo.st_mode))) | |
2498 | report_error ("%s: is a directory", args[0]); | |
2499 | else | |
2500 | file_error (args[0]); | |
2501 | ||
2502 | return (EXECUTION_FAILURE); | |
2503 | } | |
2504 | else | |
2505 | { | |
2506 | subshell_argc = larray; | |
2507 | subshell_argv = args; | |
2508 | subshell_envp = env; | |
2509 | longjmp (subshell_top_level, 1); | |
2510 | } | |
2511 | } | |
2512 | } | |
2513 | } | |
2514 | ||
2515 | #if defined (PROCESS_SUBSTITUTION) | |
2516 | /* Currently unused */ | |
2517 | void | |
2518 | close_all_files () | |
2519 | { | |
2520 | register int i, fd_table_size; | |
2521 | ||
2522 | fd_table_size = getdtablesize (); | |
2523 | if (fd_table_size > 256) /* clamp to a reasonable value */ | |
2524 | fd_table_size = 256; | |
2525 | ||
2526 | for (i = 3; i < fd_table_size; i++) | |
2527 | close (i); | |
2528 | } | |
2529 | #endif /* PROCESS_SUBSTITUTION */ | |
2530 | ||
2531 | static void | |
2532 | close_pipes (in, out) | |
2533 | int in, out; | |
2534 | { | |
2535 | if (in >= 0) | |
2536 | close (in); | |
2537 | if (out >= 0) | |
2538 | close (out); | |
2539 | } | |
2540 | ||
2541 | /* Redirect input and output to be from and to the specified pipes. | |
2542 | NO_PIPE and REDIRECT_BOTH are handled correctly. */ | |
2543 | static void | |
2544 | do_piping (pipe_in, pipe_out) | |
2545 | int pipe_in, pipe_out; | |
2546 | { | |
2547 | if (pipe_in != NO_PIPE) | |
2548 | { | |
2549 | if (dup2 (pipe_in, 0) < 0) | |
2550 | internal_error ("cannot duplicate fd %d to fd 0: %s", | |
2551 | pipe_in, strerror (errno)); | |
2552 | if (pipe_in > 0) | |
2553 | close (pipe_in); | |
2554 | } | |
2555 | if (pipe_out != NO_PIPE) | |
2556 | { | |
2557 | if (pipe_out != REDIRECT_BOTH) | |
2558 | { | |
2559 | if (dup2 (pipe_out, 1) < 0) | |
2560 | internal_error ("cannot duplicate fd %d to fd 1: %s", | |
2561 | pipe_out, strerror (errno)); | |
2562 | if (pipe_out == 0 || pipe_out > 1) | |
2563 | close (pipe_out); | |
2564 | } | |
2565 | else | |
2566 | dup2 (1, 2); | |
2567 | } | |
2568 | } | |
2569 | ||
2570 | #define AMBIGUOUS_REDIRECT -1 | |
2571 | #define NOCLOBBER_REDIRECT -2 | |
2572 | #define RESTRICTED_REDIRECT -3 /* Only can happen in restricted shells. */ | |
2573 | ||
2574 | /* Perform the redirections on LIST. If FOR_REAL, then actually make | |
2575 | input and output file descriptors, otherwise just do whatever is | |
2576 | neccessary for side effecting. INTERNAL says to remember how to | |
2577 | undo the redirections later, if non-zero. If SET_CLEXEC is non-zero, | |
2578 | file descriptors opened in do_redirection () have their close-on-exec | |
2579 | flag set. */ | |
2580 | static int | |
2581 | do_redirections (list, for_real, internal, set_clexec) | |
2582 | REDIRECT *list; | |
2583 | int for_real, internal, set_clexec; | |
2584 | { | |
2585 | register int error; | |
2586 | register REDIRECT *temp = list; | |
2587 | ||
2588 | if (internal) | |
2589 | { | |
2590 | if (redirection_undo_list) | |
2591 | { | |
2592 | dispose_redirects (redirection_undo_list); | |
2593 | redirection_undo_list = (REDIRECT *)NULL; | |
2594 | } | |
2595 | if (exec_redirection_undo_list) | |
2596 | dispose_exec_redirects (); | |
2597 | } | |
2598 | ||
2599 | while (temp) | |
2600 | { | |
2601 | error = do_redirection_internal (temp, for_real, internal, set_clexec); | |
2602 | ||
2603 | if (error) | |
2604 | { | |
2605 | char *filename; | |
2606 | ||
2607 | if (expandable_redirection_filename (temp)) | |
2608 | { | |
2609 | if (posixly_correct && !interactive_shell) | |
2610 | disallow_filename_globbing++; | |
2611 | filename = redirection_expand (temp->redirectee.filename); | |
2612 | if (posixly_correct && !interactive_shell) | |
2613 | disallow_filename_globbing--; | |
2614 | ||
2615 | if (!filename) | |
2616 | filename = savestring (""); | |
2617 | } | |
2618 | else | |
2619 | filename = itos (temp->redirectee.dest); | |
2620 | ||
2621 | switch (error) | |
2622 | { | |
2623 | case AMBIGUOUS_REDIRECT: | |
2624 | report_error ("%s: Ambiguous redirect", filename); | |
2625 | break; | |
2626 | ||
2627 | case NOCLOBBER_REDIRECT: | |
2628 | report_error ("%s: Cannot clobber existing file", filename); | |
2629 | break; | |
2630 | ||
2631 | #if defined (RESTRICTED_SHELL) | |
2632 | case RESTRICTED_REDIRECT: | |
2633 | report_error ("%s: output redirection restricted", filename); | |
2634 | break; | |
2635 | #endif /* RESTRICTED_SHELL */ | |
2636 | ||
2637 | default: | |
2638 | report_error ("%s: %s", filename, strerror (error)); | |
2639 | break; | |
2640 | } | |
2641 | ||
2642 | free (filename); | |
2643 | return (error); | |
2644 | } | |
2645 | ||
2646 | temp = temp->next; | |
2647 | } | |
2648 | return (0); | |
2649 | } | |
2650 | ||
2651 | /* Return non-zero if the redirection pointed to by REDIRECT has a | |
2652 | redirectee.filename that can be expanded. */ | |
2653 | static int | |
2654 | expandable_redirection_filename (redirect) | |
2655 | REDIRECT *redirect; | |
2656 | { | |
2657 | int result; | |
2658 | ||
2659 | switch (redirect->instruction) | |
2660 | { | |
2661 | case r_output_direction: | |
2662 | case r_appending_to: | |
2663 | case r_input_direction: | |
2664 | case r_inputa_direction: | |
2665 | case r_err_and_out: | |
2666 | case r_input_output: | |
2667 | case r_output_force: | |
2668 | case r_duplicating_input_word: | |
2669 | case r_duplicating_output_word: | |
2670 | result = 1; | |
2671 | break; | |
2672 | ||
2673 | default: | |
2674 | result = 0; | |
2675 | } | |
2676 | return (result); | |
2677 | } | |
2678 | \f | |
2679 | /* Expand the word in WORD returning a string. If WORD expands to | |
2680 | multiple words (or no words), then return NULL. */ | |
2681 | char * | |
2682 | redirection_expand (word) | |
2683 | WORD_DESC *word; | |
2684 | { | |
2685 | char *result; | |
2686 | WORD_LIST *tlist1, *tlist2; | |
2687 | ||
2688 | tlist1 = make_word_list (copy_word (word), (WORD_LIST *)NULL); | |
2689 | tlist2 = expand_words_no_vars (tlist1); | |
2690 | dispose_words (tlist1); | |
2691 | ||
2692 | if (!tlist2 || tlist2->next) | |
2693 | { | |
2694 | /* We expanded to no words, or to more than a single word. | |
2695 | Dispose of the word list and return NULL. */ | |
2696 | if (tlist2) | |
2697 | dispose_words (tlist2); | |
2698 | return ((char *)NULL); | |
2699 | } | |
2700 | result = string_list (tlist2); | |
2701 | dispose_words (tlist2); | |
2702 | return (result); | |
2703 | } | |
2704 | ||
2705 | /* Do the specific redirection requested. Returns errno in case of error. | |
2706 | If FOR_REAL is zero, then just do whatever is neccessary to produce the | |
2707 | appropriate side effects. REMEMBERING, if non-zero, says to remember | |
2708 | how to undo each redirection. If SET_CLEXEC is non-zero, then | |
2709 | we set all file descriptors > 2 that we open to be close-on-exec. */ | |
2710 | static int | |
2711 | do_redirection_internal (redirect, for_real, remembering, set_clexec) | |
2712 | REDIRECT *redirect; | |
2713 | int for_real, remembering, set_clexec; | |
2714 | { | |
2715 | WORD_DESC *redirectee = redirect->redirectee.filename; | |
2716 | int redir_fd = redirect->redirectee.dest; | |
2717 | int fd, redirector = redirect->redirector; | |
2718 | char *redirectee_word; | |
2719 | enum r_instruction ri = redirect->instruction; | |
2720 | REDIRECT *new_redirect; | |
2721 | ||
2722 | if (ri == r_duplicating_input_word || ri == r_duplicating_output_word) | |
2723 | { | |
2724 | /* We have [N]>&WORD or [N]<&WORD. Expand WORD, then translate | |
2725 | the redirection into a new one and continue. */ | |
2726 | redirectee_word = redirection_expand (redirectee); | |
2727 | ||
2728 | if (redirectee_word[0] == '-' && redirectee_word[1] == '\0') | |
2729 | { | |
2730 | rd.dest = 0L; | |
2731 | new_redirect = make_redirection (redirector, r_close_this, rd); | |
2732 | } | |
2733 | else if (all_digits (redirectee_word)) | |
2734 | { | |
2735 | if (ri == r_duplicating_input_word) | |
2736 | { | |
2737 | rd.dest = atol (redirectee_word); | |
2738 | new_redirect = make_redirection (redirector, r_duplicating_input, rd); | |
2739 | } | |
2740 | else | |
2741 | { | |
2742 | rd.dest = atol (redirectee_word); | |
2743 | new_redirect = make_redirection (redirector, r_duplicating_output, rd); | |
2744 | } | |
2745 | } | |
2746 | else if (ri == r_duplicating_output_word && redirector == 1) | |
2747 | { | |
2748 | if (!posixly_correct) | |
2749 | { | |
2750 | rd.filename = make_word (redirectee_word); | |
2751 | new_redirect = make_redirection (1, r_err_and_out, rd); | |
2752 | } | |
2753 | else | |
2754 | new_redirect = copy_redirect (redirect); | |
2755 | } | |
2756 | else | |
2757 | { | |
2758 | free (redirectee_word); | |
2759 | return (AMBIGUOUS_REDIRECT); | |
2760 | } | |
2761 | ||
2762 | free (redirectee_word); | |
2763 | ||
2764 | /* Set up the variables needed by the rest of the function from the | |
2765 | new redirection. */ | |
2766 | if (new_redirect->instruction == r_err_and_out) | |
2767 | { | |
2768 | char *alloca_hack; | |
2769 | ||
2770 | /* Copy the word without allocating any memory that must be | |
2771 | explicitly freed. */ | |
2772 | redirectee = (WORD_DESC *)alloca (sizeof (WORD_DESC)); | |
2773 | xbcopy ((char *)new_redirect->redirectee.filename, | |
2774 | (char *)redirectee, sizeof (WORD_DESC)); | |
2775 | ||
2776 | alloca_hack = (char *) | |
2777 | alloca (1 + strlen (new_redirect->redirectee.filename->word)); | |
2778 | redirectee->word = alloca_hack; | |
2779 | strcpy (redirectee->word, new_redirect->redirectee.filename->word); | |
2780 | } | |
2781 | else | |
2782 | /* It's guaranteed to be an integer, and shouldn't be freed. */ | |
2783 | redirectee = new_redirect->redirectee.filename; | |
2784 | ||
2785 | redir_fd = new_redirect->redirectee.dest; | |
2786 | redirector = new_redirect->redirector; | |
2787 | ri = new_redirect->instruction; | |
2788 | ||
2789 | /* Overwrite the flags element of the old redirect with the new value. */ | |
2790 | redirect->flags = new_redirect->flags; | |
2791 | dispose_redirects (new_redirect); | |
2792 | } | |
2793 | ||
2794 | switch (ri) | |
2795 | { | |
2796 | case r_output_direction: | |
2797 | case r_appending_to: | |
2798 | case r_input_direction: | |
2799 | case r_inputa_direction: | |
2800 | case r_err_and_out: /* command &>filename */ | |
2801 | case r_input_output: | |
2802 | case r_output_force: | |
2803 | ||
2804 | if (posixly_correct && !interactive_shell) | |
2805 | disallow_filename_globbing++; | |
2806 | redirectee_word = redirection_expand (redirectee); | |
2807 | if (posixly_correct && !interactive_shell) | |
2808 | disallow_filename_globbing--; | |
2809 | ||
2810 | if (!redirectee_word) | |
2811 | return (AMBIGUOUS_REDIRECT); | |
2812 | ||
2813 | #if defined (RESTRICTED_SHELL) | |
2814 | if (restricted && (ri == r_output_direction || | |
2815 | ri == r_input_output || | |
2816 | ri == r_err_and_out || | |
2817 | ri == r_appending_to || | |
2818 | ri == r_output_force)) | |
2819 | { | |
2820 | free (redirectee_word); | |
2821 | return (RESTRICTED_REDIRECT); | |
2822 | } | |
2823 | #endif /* RESTRICTED_SHELL */ | |
2824 | ||
2825 | /* If we are in noclobber mode, you are not allowed to overwrite | |
2826 | existing files. Check first. */ | |
2827 | if (noclobber && (ri == r_output_direction || | |
2828 | ri == r_input_output || | |
2829 | ri == r_err_and_out)) | |
2830 | { | |
2831 | struct stat finfo; | |
2832 | int stat_result; | |
2833 | ||
2834 | stat_result = stat (redirectee_word, &finfo); | |
2835 | ||
2836 | if ((stat_result == 0) && (S_ISREG (finfo.st_mode))) | |
2837 | { | |
2838 | free (redirectee_word); | |
2839 | return (NOCLOBBER_REDIRECT); | |
2840 | } | |
2841 | ||
2842 | /* If the file was not present, make sure we open it exclusively | |
2843 | so that if it is created before we open it, our open will fail. */ | |
2844 | if (stat_result != 0) | |
2845 | redirect->flags |= O_EXCL; | |
2846 | ||
2847 | fd = open (redirectee_word, redirect->flags, 0666); | |
2848 | ||
2849 | if ((fd < 0) && (errno == EEXIST)) | |
2850 | { | |
2851 | free (redirectee_word); | |
2852 | return (NOCLOBBER_REDIRECT); | |
2853 | } | |
2854 | } | |
2855 | else | |
2856 | { | |
2857 | fd = open (redirectee_word, redirect->flags, 0666); | |
2858 | #if defined (AFS_CREATE_BUG) | |
2859 | if ((fd < 0) && (errno == EACCES)) | |
2860 | fd = open (redirectee_word, (redirect->flags & ~O_CREAT), 0666); | |
2861 | #endif /* AFS_CREATE_BUG */ | |
2862 | } | |
2863 | free (redirectee_word); | |
2864 | ||
2865 | if (fd < 0) | |
2866 | return (errno); | |
2867 | ||
2868 | if (for_real) | |
2869 | { | |
2870 | if (remembering) | |
2871 | /* Only setup to undo it if the thing to undo is active. */ | |
2872 | if ((fd != redirector) && (fcntl (redirector, F_GETFD, 0) != -1)) | |
2873 | add_undo_redirect (redirector); | |
2874 | else | |
2875 | add_undo_close_redirect (redirector); | |
2876 | ||
2877 | #if defined (BUFFERED_INPUT) | |
2878 | check_bash_input (redirector); | |
2879 | #endif | |
2880 | ||
2881 | if ((fd != redirector) && (dup2 (fd, redirector) < 0)) | |
2882 | return (errno); | |
2883 | ||
2884 | #if defined (BUFFERED_INPUT) | |
2885 | /* Do not change the buffered stream for an implicit redirection | |
2886 | of /dev/null to fd 0 for asynchronous commands without job | |
2887 | control (r_inputa_direction). */ | |
2888 | if (ri == r_input_direction || ri == r_input_output) | |
2889 | duplicate_buffered_stream (fd, redirector); | |
2890 | #endif /* BUFFERED_INPUT */ | |
2891 | ||
2892 | /* | |
2893 | * If we're remembering, then this is the result of a while, for | |
2894 | * or until loop with a loop redirection, or a function/builtin | |
2895 | * executing in the parent shell with a redirection. In the | |
2896 | * function/builtin case, we want to set all file descriptors > 2 | |
2897 | * to be close-on-exec to duplicate the effect of the old | |
2898 | * for i = 3 to NOFILE close(i) loop. In the case of the loops, | |
2899 | * both sh and ksh leave the file descriptors open across execs. | |
2900 | * The Posix standard mentions only the exec builtin. | |
2901 | */ | |
2902 | if (set_clexec && (redirector > 2)) | |
2903 | SET_CLOSE_ON_EXEC (redirector); | |
2904 | } | |
2905 | ||
2906 | if (fd != redirector) | |
2907 | { | |
2908 | #if defined (BUFFERED_INPUT) | |
2909 | if (ri == r_input_direction || ri == r_inputa_direction || | |
2910 | ri == r_input_output) | |
2911 | close_buffered_fd (fd); | |
2912 | else | |
2913 | #endif /* !BUFFERED_INPUT */ | |
2914 | close (fd); /* Don't close what we just opened! */ | |
2915 | } | |
2916 | ||
2917 | /* If we are hacking both stdout and stderr, do the stderr | |
2918 | redirection here. */ | |
2919 | if (ri == r_err_and_out) | |
2920 | { | |
2921 | if (for_real) | |
2922 | { | |
2923 | if (remembering) | |
2924 | add_undo_redirect (2); | |
2925 | if (dup2 (1, 2) < 0) | |
2926 | return (errno); | |
2927 | } | |
2928 | } | |
2929 | break; | |
2930 | ||
2931 | case r_reading_until: | |
2932 | case r_deblank_reading_until: | |
2933 | /* REDIRECTEE is a pointer to a WORD_DESC containing the text of | |
2934 | the new input. Place it in a temporary file. */ | |
2935 | if (redirectee) | |
2936 | { | |
2937 | char filename[40]; | |
2938 | pid_t pid = getpid (); | |
2939 | ||
2940 | /* Make the filename for the temp file. */ | |
2941 | sprintf (filename, "/tmp/t%d-sh", pid); | |
2942 | ||
2943 | fd = open (filename, O_TRUNC | O_WRONLY | O_CREAT, 0666); | |
2944 | if (fd < 0) | |
2945 | return (errno); | |
2946 | ||
2947 | errno = 0; /* XXX */ | |
2948 | if (redirectee->word) | |
2949 | { | |
2950 | char *document; | |
2951 | int document_len; | |
2952 | ||
2953 | /* Expand the text if the word that was specified had | |
2954 | no quoting. The text that we expand is treated | |
2955 | exactly as if it were surrounded by double quotes. */ | |
2956 | ||
2957 | if (redirectee->quoted) | |
2958 | { | |
2959 | document = redirectee->word; | |
2960 | document_len = strlen (document); | |
2961 | /* Set errno to something reasonable if the write fails. */ | |
2962 | if (write (fd, document, document_len) < document_len) | |
2963 | { | |
2964 | if (errno == 0) | |
2965 | errno = ENOSPC; | |
2966 | close (fd); | |
2967 | return (errno); | |
2968 | } | |
2969 | } | |
2970 | else | |
2971 | { | |
2972 | WORD_LIST *tlist; | |
2973 | tlist = expand_string (redirectee->word, Q_HERE_DOCUMENT); | |
2974 | if (tlist) | |
2975 | { | |
2976 | int fd2; | |
2977 | FILE *fp; | |
2978 | register WORD_LIST *t; | |
2979 | ||
2980 | /* Try using buffered I/O (stdio) and writing a word | |
2981 | at a time, letting stdio do the work of buffering | |
2982 | for us rather than managing our own strings. Most | |
2983 | stdios are not particularly fast, however -- this | |
2984 | may need to be reconsidered later. */ | |
2985 | if ((fd2 = dup (fd)) < 0 || | |
2986 | (fp = fdopen (fd2, "w")) == NULL) | |
2987 | { | |
2988 | if (fd2 >= 0) | |
2989 | close (fd2); | |
2990 | close (fd); | |
2991 | return (errno); | |
2992 | } | |
2993 | errno = 0; /* XXX */ | |
2994 | for (t = tlist; t; t = t->next) | |
2995 | { | |
2996 | /* This is essentially the body of | |
2997 | string_list_internal expanded inline. */ | |
2998 | document = t->word->word; | |
2999 | document_len = strlen (document); | |
3000 | if (t != tlist) | |
3001 | putc (' ', fp); /* separator */ | |
3002 | fwrite (document, document_len, 1, fp); | |
3003 | if (ferror (fp)) | |
3004 | { | |
3005 | if (errno == 0) | |
3006 | errno = ENOSPC; | |
3007 | break; | |
3008 | } | |
3009 | } | |
3010 | fclose (fp); | |
3011 | dispose_words (tlist); | |
3012 | } | |
3013 | } | |
3014 | } | |
3015 | ||
3016 | close (fd); | |
3017 | if (errno) | |
3018 | return (errno); | |
3019 | ||
3020 | /* Make the document really temporary. Also make it the input. */ | |
3021 | fd = open (filename, O_RDONLY, 0666); | |
3022 | ||
3023 | if (unlink (filename) < 0 || fd < 0) | |
3024 | { | |
3025 | if (fd >= 0) | |
3026 | close (fd); | |
3027 | return (errno); | |
3028 | } | |
3029 | ||
3030 | if (for_real) | |
3031 | { | |
3032 | if (remembering) | |
3033 | /* Only setup to undo it if the thing to undo is active. */ | |
3034 | if ((fd != redirector) && (fcntl (redirector, F_GETFD, 0) != -1)) | |
3035 | add_undo_redirect (redirector); | |
3036 | else | |
3037 | add_undo_close_redirect (redirector); | |
3038 | ||
3039 | #if defined (BUFFERED_INPUT) | |
3040 | check_bash_input (redirector); | |
3041 | #endif | |
3042 | if (dup2 (fd, redirector) < 0) | |
3043 | { | |
3044 | close (fd); | |
3045 | return (errno); | |
3046 | } | |
3047 | ||
3048 | #if defined (BUFFERED_INPUT) | |
3049 | duplicate_buffered_stream (fd, redirector); | |
3050 | #endif | |
3051 | ||
3052 | if (set_clexec && (redirector > 2)) | |
3053 | SET_CLOSE_ON_EXEC (redirector); | |
3054 | } | |
3055 | ||
3056 | #if defined (BUFFERED_INPUT) | |
3057 | close_buffered_fd (fd); | |
3058 | #else | |
3059 | close (fd); | |
3060 | #endif | |
3061 | } | |
3062 | break; | |
3063 | ||
3064 | case r_duplicating_input: | |
3065 | case r_duplicating_output: | |
3066 | if (for_real && (redir_fd != redirector)) | |
3067 | { | |
3068 | if (remembering) | |
3069 | /* Only setup to undo it if the thing to undo is active. */ | |
3070 | if (fcntl (redirector, F_GETFD, 0) != -1) | |
3071 | add_undo_redirect (redirector); | |
3072 | else | |
3073 | add_undo_close_redirect (redirector); | |
3074 | ||
3075 | #if defined (BUFFERED_INPUT) | |
3076 | check_bash_input (redirector); | |
3077 | #endif | |
3078 | /* This is correct. 2>&1 means dup2 (1, 2); */ | |
3079 | if (dup2 (redir_fd, redirector) < 0) | |
3080 | return (errno); | |
3081 | ||
3082 | #if defined (BUFFERED_INPUT) | |
3083 | if (ri == r_duplicating_input) | |
3084 | duplicate_buffered_stream (redir_fd, redirector); | |
3085 | #endif /* BUFFERED_INPUT */ | |
3086 | ||
3087 | /* First duplicate the close-on-exec state of redirectee. dup2 | |
3088 | leaves the flag unset on the new descriptor, which means it | |
3089 | stays open. Only set the close-on-exec bit for file descriptors | |
3090 | greater than 2 in any case, since 0-2 should always be open | |
3091 | unless closed by something like `exec 2<&-'. */ | |
3092 | /* if ((already_set || set_unconditionally) && (ok_to_set)) | |
3093 | set_it () */ | |
3094 | if (((fcntl (redir_fd, F_GETFD, 0) == 1) || set_clexec) && | |
3095 | (redirector > 2)) | |
3096 | SET_CLOSE_ON_EXEC (redirector); | |
3097 | } | |
3098 | break; | |
3099 | ||
3100 | case r_close_this: | |
3101 | if (for_real) | |
3102 | { | |
3103 | if (remembering && (fcntl (redirector, F_GETFD, 0) != -1)) | |
3104 | add_undo_redirect (redirector); | |
3105 | ||
3106 | #if defined (BUFFERED_INPUT) | |
3107 | check_bash_input (redirector); | |
3108 | close_buffered_fd (redirector); | |
3109 | #else /* !BUFFERED_INPUT */ | |
3110 | close (redirector); | |
3111 | #endif /* !BUFFERED_INPUT */ | |
3112 | } | |
3113 | break; | |
3114 | } | |
3115 | return (0); | |
3116 | } | |
3117 | ||
3118 | #define SHELL_FD_BASE 10 | |
3119 | ||
3120 | /* Remember the file descriptor associated with the slot FD, | |
3121 | on REDIRECTION_UNDO_LIST. Note that the list will be reversed | |
3122 | before it is executed. Any redirections that need to be undone | |
3123 | even if REDIRECTION_UNDO_LIST is discarded by the exec builtin | |
3124 | are also saved on EXEC_REDIRECTION_UNDO_LIST. */ | |
3125 | static int | |
3126 | add_undo_redirect (fd) | |
3127 | int fd; | |
3128 | { | |
3129 | int new_fd, clexec_flag; | |
3130 | REDIRECT *new_redirect, *closer; | |
3131 | ||
3132 | new_fd = fcntl (fd, F_DUPFD, SHELL_FD_BASE); | |
3133 | ||
3134 | if (new_fd < 0) | |
3135 | { | |
3136 | file_error ("redirection error"); | |
3137 | return (-1); | |
3138 | } | |
3139 | else | |
3140 | { | |
3141 | REDIRECT *dummy_redirect; | |
3142 | ||
3143 | clexec_flag = fcntl (fd, F_GETFD, 0); | |
3144 | ||
3145 | rd.dest = 0L; | |
3146 | closer = make_redirection (new_fd, r_close_this, rd); | |
3147 | dummy_redirect = copy_redirects (closer); | |
3148 | ||
3149 | rd.dest = (long)new_fd; | |
3150 | new_redirect = make_redirection (fd, r_duplicating_output, rd); | |
3151 | new_redirect->next = closer; | |
3152 | ||
3153 | closer->next = redirection_undo_list; | |
3154 | redirection_undo_list = new_redirect; | |
3155 | ||
3156 | /* Save redirections that need to be undone even if the undo list | |
3157 | is thrown away by the `exec' builtin. */ | |
3158 | add_exec_redirect (dummy_redirect); | |
3159 | ||
3160 | /* File descriptors used only for saving others should always be | |
3161 | marked close-on-exec. Unfortunately, we have to preserve the | |
3162 | close-on-exec state of the file descriptor we are saving, since | |
3163 | fcntl (F_DUPFD) sets the new file descriptor to remain open | |
3164 | across execs. If, however, the file descriptor whose state we | |
3165 | are saving is <= 2, we can just set the close-on-exec flag, | |
3166 | because file descriptors 0-2 should always be open-on-exec, | |
3167 | and the restore above in do_redirection() will take care of it. */ | |
3168 | if (clexec_flag || fd < 3) | |
3169 | SET_CLOSE_ON_EXEC (new_fd); | |
3170 | } | |
3171 | return (0); | |
3172 | } | |
3173 | ||
3174 | /* Set up to close FD when we are finished with the current command | |
3175 | and its redirections. */ | |
3176 | static void | |
3177 | add_undo_close_redirect (fd) | |
3178 | int fd; | |
3179 | { | |
3180 | REDIRECT *closer; | |
3181 | ||
3182 | rd.dest = 0L; | |
3183 | closer = make_redirection (fd, r_close_this, rd); | |
3184 | closer->next = redirection_undo_list; | |
3185 | redirection_undo_list = closer; | |
3186 | } | |
3187 | ||
3188 | static void | |
3189 | add_exec_redirect (dummy_redirect) | |
3190 | REDIRECT *dummy_redirect; | |
3191 | { | |
3192 | dummy_redirect->next = exec_redirection_undo_list; | |
3193 | exec_redirection_undo_list = dummy_redirect; | |
3194 | } | |
3195 | ||
3196 | intern_function (name, function) | |
3197 | WORD_DESC *name; | |
3198 | COMMAND *function; | |
3199 | { | |
3200 | SHELL_VAR *var; | |
3201 | ||
3202 | if (!check_identifier (name, posixly_correct)) | |
3203 | return (EXECUTION_FAILURE); | |
3204 | ||
3205 | var = find_function (name->word); | |
3206 | if (var && readonly_p (var)) | |
3207 | { | |
3208 | report_error ("%s: readonly function", var->name); | |
3209 | return (EXECUTION_FAILURE); | |
3210 | } | |
3211 | ||
3212 | bind_function (name->word, function); | |
3213 | return (EXECUTION_SUCCESS); | |
3214 | } | |
3215 | ||
3216 | #define u_mode_bits(x) (((x) & 0000700) >> 6) | |
3217 | #define g_mode_bits(x) (((x) & 0000070) >> 3) | |
3218 | #define o_mode_bits(x) (((x) & 0000007) >> 0) | |
3219 | #define X_BIT(x) ((x) & 1) | |
3220 | ||
3221 | /* Return some flags based on information about this file. | |
3222 | The EXISTS bit is non-zero if the file is found. | |
3223 | The EXECABLE bit is non-zero the file is executble. | |
3224 | Zero is returned if the file is not found. */ | |
3225 | int | |
3226 | file_status (name) | |
3227 | char *name; | |
3228 | { | |
3229 | struct stat finfo; | |
3230 | static int user_id = -1; | |
3231 | ||
3232 | /* Determine whether this file exists or not. */ | |
3233 | if (stat (name, &finfo) < 0) | |
3234 | return (0); | |
3235 | ||
3236 | /* If the file is a directory, then it is not "executable" in the | |
3237 | sense of the shell. */ | |
3238 | if (S_ISDIR (finfo.st_mode)) | |
3239 | return (FS_EXISTS); | |
3240 | ||
3241 | #if defined (AFS) | |
3242 | /* We have to use access(2) to determine access because AFS does not | |
3243 | support Unix file system semantics. This may produce wrong | |
3244 | answers for non-AFS files when ruid != euid. I hate AFS. */ | |
3245 | if (access (name, X_OK) == 0) | |
3246 | return (FS_EXISTS | FS_EXECABLE); | |
3247 | else | |
3248 | return (FS_EXISTS); | |
3249 | #else /* !AFS */ | |
3250 | ||
3251 | /* Find out if the file is actually executable. By definition, the | |
3252 | only other criteria is that the file has an execute bit set that | |
3253 | we can use. */ | |
3254 | if (user_id == -1) | |
3255 | user_id = current_user.euid; | |
3256 | ||
3257 | /* Root only requires execute permission for any of owner, group or | |
3258 | others to be able to exec a file. */ | |
3259 | if (user_id == 0) | |
3260 | { | |
3261 | int bits; | |
3262 | ||
3263 | bits = (u_mode_bits (finfo.st_mode) | | |
3264 | g_mode_bits (finfo.st_mode) | | |
3265 | o_mode_bits (finfo.st_mode)); | |
3266 | ||
3267 | if (X_BIT (bits)) | |
3268 | return (FS_EXISTS | FS_EXECABLE); | |
3269 | } | |
3270 | ||
3271 | /* If we are the owner of the file, the owner execute bit applies. */ | |
3272 | if (user_id == finfo.st_uid && X_BIT (u_mode_bits (finfo.st_mode))) | |
3273 | return (FS_EXISTS | FS_EXECABLE); | |
3274 | ||
3275 | /* If we are in the owning group, the group permissions apply. */ | |
3276 | if (group_member (finfo.st_gid) && X_BIT (g_mode_bits (finfo.st_mode))) | |
3277 | return (FS_EXISTS | FS_EXECABLE); | |
3278 | ||
3279 | /* If `others' have execute permission to the file, then so do we, | |
3280 | since we are also `others'. */ | |
3281 | if (X_BIT (o_mode_bits (finfo.st_mode))) | |
3282 | return (FS_EXISTS | FS_EXECABLE); | |
3283 | else | |
3284 | return (FS_EXISTS); | |
3285 | #endif /* !AFS */ | |
3286 | } | |
3287 | ||
3288 | /* Return non-zero if FILE exists and is executable. | |
3289 | Note that this function is the definition of what an | |
3290 | executable file is; do not change this unless YOU know | |
3291 | what an executable file is. */ | |
3292 | int | |
3293 | executable_file (file) | |
3294 | char *file; | |
3295 | { | |
3296 | return (file_status (file) & FS_EXECABLE); | |
3297 | } | |
3298 | ||
3299 | /* DOT_FOUND_IN_SEARCH becomes non-zero when find_user_command () | |
3300 | encounters a `.' as the directory pathname while scanning the | |
3301 | list of possible pathnames; i.e., if `.' comes before the directory | |
3302 | containing the file of interest. */ | |
3303 | int dot_found_in_search = 0; | |
3304 | ||
3305 | /* Locate the executable file referenced by NAME, searching along | |
3306 | the contents of the shell PATH variable. Return a new string | |
3307 | which is the full pathname to the file, or NULL if the file | |
3308 | couldn't be found. If a file is found that isn't executable, | |
3309 | and that is the only match, then return that. */ | |
3310 | char * | |
3311 | find_user_command (name) | |
3312 | char *name; | |
3313 | { | |
3314 | return (find_user_command_internal (name, FS_EXEC_PREFERRED)); | |
3315 | } | |
3316 | ||
3317 | /* Locate the file referenced by NAME, searching along the contents | |
3318 | of the shell PATH variable. Return a new string which is the full | |
3319 | pathname to the file, or NULL if the file couldn't be found. This | |
3320 | returns the first file found. */ | |
3321 | char * | |
3322 | find_path_file (name) | |
3323 | char *name; | |
3324 | { | |
3325 | return (find_user_command_internal (name, FS_EXISTS)); | |
3326 | } | |
3327 | ||
3328 | static char * | |
3329 | find_user_command_internal (name, flags) | |
3330 | char *name; | |
3331 | int flags; | |
3332 | { | |
3333 | char *path_list; | |
3334 | SHELL_VAR *var; | |
3335 | ||
3336 | /* Search for the value of PATH in both the temporary environment, and | |
3337 | in the regular list of variables. */ | |
3338 | if (var = find_variable_internal ("PATH", 1)) | |
3339 | path_list = value_cell (var); | |
3340 | else | |
3341 | path_list = (char *)NULL; | |
3342 | ||
3343 | if (path_list == 0 || *path_list == '\0') | |
3344 | return (savestring (name)); | |
3345 | ||
3346 | return (find_user_command_in_path (name, path_list, flags)); | |
3347 | } | |
3348 | ||
3349 | /* Return the next element from PATH_LIST, a colon separated list of | |
3350 | paths. PATH_INDEX_POINTER is the address of an index into PATH_LIST; | |
3351 | the index is modified by this function. | |
3352 | Return the next element of PATH_LIST or NULL if there are no more. */ | |
3353 | static char * | |
3354 | get_next_path_element (path_list, path_index_pointer) | |
3355 | char *path_list; | |
3356 | int *path_index_pointer; | |
3357 | { | |
3358 | char *path; | |
3359 | ||
3360 | path = extract_colon_unit (path_list, path_index_pointer); | |
3361 | ||
3362 | if (!path) | |
3363 | return (path); | |
3364 | ||
3365 | if (!*path) | |
3366 | { | |
3367 | free (path); | |
3368 | path = savestring ("."); | |
3369 | } | |
3370 | ||
3371 | return (path); | |
3372 | } | |
3373 | ||
3374 | char * | |
3375 | user_command_matches (name, flags, state) | |
3376 | char *name; | |
3377 | int flags, state; | |
3378 | { | |
3379 | register int i; | |
3380 | char *path_list; | |
3381 | int path_index; | |
3382 | char *path_element; | |
3383 | char *match; | |
3384 | static char **match_list = NULL; | |
3385 | static int match_list_size = 0; | |
3386 | static int match_index = 0; | |
3387 | ||
3388 | if (!state) | |
3389 | { | |
3390 | /* Create the list of matches. */ | |
3391 | if (!match_list) | |
3392 | { | |
3393 | match_list = | |
3394 | (char **) xmalloc ((match_list_size = 5) * sizeof(char *)); | |
3395 | ||
3396 | for (i = 0; i < match_list_size; i++) | |
3397 | match_list[i] = 0; | |
3398 | } | |
3399 | ||
3400 | /* Clear out the old match list. */ | |
3401 | for (i = 0; i < match_list_size; i++) | |
3402 | match_list[i] = NULL; | |
3403 | ||
3404 | /* We haven't found any files yet. */ | |
3405 | match_index = 0; | |
3406 | ||
3407 | path_list = get_string_value ("PATH"); | |
3408 | path_index = 0; | |
3409 | ||
3410 | while (path_list && path_list[path_index]) | |
3411 | { | |
3412 | path_element = get_next_path_element (path_list, &path_index); | |
3413 | ||
3414 | if (!path_element) | |
3415 | break; | |
3416 | ||
3417 | match = find_user_command_in_path (name, path_element, flags); | |
3418 | ||
3419 | free (path_element); | |
3420 | ||
3421 | if (!match) | |
3422 | continue; | |
3423 | ||
3424 | if (match_index + 1 == match_list_size) | |
3425 | match_list = (char **)xrealloc | |
3426 | (match_list, ((match_list_size += 10) + 1) * sizeof (char *)); | |
3427 | match_list[match_index++] = match; | |
3428 | match_list[match_index] = (char *)NULL; | |
3429 | } | |
3430 | ||
3431 | /* We haven't returned any strings yet. */ | |
3432 | match_index = 0; | |
3433 | } | |
3434 | ||
3435 | match = match_list[match_index]; | |
3436 | ||
3437 | if (match) | |
3438 | match_index++; | |
3439 | ||
3440 | return (match); | |
3441 | } | |
3442 | ||
3443 | /* Return 1 if PATH1 and PATH2 are the same file. This is kind of | |
3444 | expensive. If non-NULL STP1 and STP2 point to stat structures | |
3445 | corresponding to PATH1 and PATH2, respectively. */ | |
3446 | int | |
3447 | same_file (path1, path2, stp1, stp2) | |
3448 | char *path1, *path2; | |
3449 | struct stat *stp1, *stp2; | |
3450 | { | |
3451 | struct stat st1, st2; | |
3452 | ||
3453 | if (stp1 == NULL) | |
3454 | { | |
3455 | if (stat (path1, &st1) != 0) | |
3456 | return (0); | |
3457 | stp1 = &st1; | |
3458 | } | |
3459 | ||
3460 | if (stp2 == NULL) | |
3461 | { | |
3462 | if (stat (path2, &st2) != 0) | |
3463 | return (0); | |
3464 | stp2 = &st2; | |
3465 | } | |
3466 | ||
3467 | return ((stp1->st_dev == stp2->st_dev) && (stp1->st_ino == stp2->st_ino)); | |
3468 | } | |
3469 | ||
3470 | /* Turn PATH, a directory, and NAME, a filename, into a full pathname. | |
3471 | This allocates new memory and returns it. */ | |
3472 | static char * | |
3473 | make_full_pathname (path, name, name_len) | |
3474 | char *path, *name; | |
3475 | int name_len; | |
3476 | { | |
3477 | char *full_path; | |
3478 | int path_len; | |
3479 | ||
3480 | path_len = strlen (path); | |
3481 | full_path = xmalloc (2 + path_len + name_len); | |
3482 | strcpy (full_path, path); | |
3483 | full_path[path_len] = '/'; | |
3484 | strcpy (full_path + path_len + 1, name); | |
3485 | return (full_path); | |
3486 | } | |
3487 | ||
3488 | /* This does the dirty work for find_path_file () and find_user_command (). | |
3489 | NAME is the name of the file to search for. | |
3490 | PATH_LIST is a colon separated list of directories to search. | |
3491 | FLAGS contains bit fields which control the files which are eligible. | |
3492 | Some values are: | |
3493 | FS_EXEC_ONLY: The file must be an executable to be found. | |
3494 | FS_EXEC_PREFERRED: If we can't find an executable, then the | |
3495 | the first file matching NAME will do. | |
3496 | FS_EXISTS: The first file found will do. | |
3497 | */ | |
3498 | static char * | |
3499 | find_user_command_in_path (name, path_list, flags) | |
3500 | char *name; | |
3501 | char *path_list; | |
3502 | int flags; | |
3503 | { | |
3504 | char *full_path, *path, *file_to_lose_on; | |
3505 | int status, path_index, name_len; | |
3506 | struct stat finfo; | |
3507 | ||
3508 | name_len = strlen (name); | |
3509 | ||
3510 | /* The file name which we would try to execute, except that it isn't | |
3511 | possible to execute it. This is the first file that matches the | |
3512 | name that we are looking for while we are searching $PATH for a | |
3513 | suitable one to execute. If we cannot find a suitable executable | |
3514 | file, then we use this one. */ | |
3515 | file_to_lose_on = (char *)NULL; | |
3516 | ||
3517 | /* We haven't started looking, so we certainly haven't seen | |
3518 | a `.' as the directory path yet. */ | |
3519 | dot_found_in_search = 0; | |
3520 | ||
3521 | if (absolute_program (name)) | |
3522 | { | |
3523 | full_path = xmalloc (1 + name_len); | |
3524 | strcpy (full_path, name); | |
3525 | ||
3526 | status = file_status (full_path); | |
3527 | ||
3528 | /* If the file doesn't exist, quit now. */ | |
3529 | if (!(status & FS_EXISTS)) | |
3530 | { | |
3531 | free (full_path); | |
3532 | return ((char *)NULL); | |
3533 | } | |
3534 | ||
3535 | /* If we only care about whether the file exists or not, return | |
3536 | this filename. */ | |
3537 | if (flags & FS_EXISTS) | |
3538 | return (full_path); | |
3539 | ||
3540 | /* Otherwise, maybe we care about whether this file is executable. | |
3541 | If it is, and that is what we want, return it. */ | |
3542 | if ((flags & FS_EXEC_ONLY) && (status & FS_EXECABLE)) | |
3543 | return (full_path); | |
3544 | else | |
3545 | { | |
3546 | free (full_path); | |
3547 | return ((char *)NULL); | |
3548 | } | |
3549 | } | |
3550 | ||
3551 | /* Find out the location of the current working directory. */ | |
3552 | stat (".", &finfo); | |
3553 | ||
3554 | path_index = 0; | |
3555 | while (path_list && path_list[path_index]) | |
3556 | { | |
3557 | /* Allow the user to interrupt out of a lengthy path search. */ | |
3558 | QUIT; | |
3559 | ||
3560 | path = get_next_path_element (path_list, &path_index); | |
3561 | ||
3562 | if (!path) | |
3563 | break; | |
3564 | ||
3565 | if (*path == '~') | |
3566 | { | |
3567 | char *t = tilde_expand (path); | |
3568 | free (path); | |
3569 | path = t; | |
3570 | } | |
3571 | ||
3572 | /* Remember the location of "." in the path, in all its forms | |
3573 | (as long as they begin with a `.', e.g. `./.') */ | |
3574 | if (!dot_found_in_search && (*path == '.') && | |
3575 | same_file (".", path, &finfo, (struct stat *)NULL)) | |
3576 | dot_found_in_search = 1; | |
3577 | ||
3578 | full_path = make_full_pathname (path, name, name_len); | |
3579 | free (path); | |
3580 | ||
3581 | status = file_status (full_path); | |
3582 | ||
3583 | if (!(status & FS_EXISTS)) | |
3584 | goto next_file; | |
3585 | ||
3586 | /* The file exists. If the caller simply wants the first file, | |
3587 | here it is. */ | |
3588 | if (flags & FS_EXISTS) | |
3589 | return (full_path); | |
3590 | ||
3591 | /* If the file is executable, then it satisfies the cases of | |
3592 | EXEC_ONLY and EXEC_PREFERRED. Return this file unconditionally. */ | |
3593 | if (status & FS_EXECABLE) | |
3594 | { | |
3595 | FREE (file_to_lose_on); | |
3596 | ||
3597 | return (full_path); | |
3598 | } | |
3599 | ||
3600 | /* The file is not executable, but it does exist. If we prefer | |
3601 | an executable, then remember this one if it is the first one | |
3602 | we have found. */ | |
3603 | if (flags & FS_EXEC_PREFERRED) | |
3604 | { | |
3605 | if (!file_to_lose_on) | |
3606 | file_to_lose_on = savestring (full_path); | |
3607 | } | |
3608 | ||
3609 | next_file: | |
3610 | free (full_path); | |
3611 | } | |
3612 | ||
3613 | /* We didn't find exactly what the user was looking for. Return | |
3614 | the contents of FILE_TO_LOSE_ON which is NULL when the search | |
3615 | required an executable, or non-NULL if a file was found and the | |
3616 | search would accept a non-executable as a last resort. */ | |
3617 | return (file_to_lose_on); | |
3618 | } | |
3619 | ||
3620 | /* Given a string containing units of information separated by colons, | |
3621 | return the next one pointed to by (P_INDEX), or NULL if there are no more. | |
3622 | Advance (P_INDEX) to the character after the colon. */ | |
3623 | char * | |
3624 | extract_colon_unit (string, p_index) | |
3625 | char *string; | |
3626 | int *p_index; | |
3627 | { | |
3628 | int i, start; | |
3629 | ||
3630 | i = *p_index; | |
3631 | ||
3632 | if (!string || (i >= (int)strlen (string))) | |
3633 | return ((char *)NULL); | |
3634 | ||
3635 | /* Each call to this routine leaves the index pointing at a colon if | |
3636 | there is more to the path. If I is > 0, then increment past the | |
3637 | `:'. If I is 0, then the path has a leading colon. Trailing colons | |
3638 | are handled OK by the `else' part of the if statement; an empty | |
3639 | string is returned in that case. */ | |
3640 | if (i && string[i] == ':') | |
3641 | i++; | |
3642 | ||
3643 | start = i; | |
3644 | ||
3645 | while (string[i] && string[i] != ':') i++; | |
3646 | ||
3647 | *p_index = i; | |
3648 | ||
3649 | if (i == start) | |
3650 | { | |
3651 | if (string[i]) | |
3652 | (*p_index)++; | |
3653 | ||
3654 | /* Return "" in the case of a trailing `:'. */ | |
3655 | return (savestring ("")); | |
3656 | } | |
3657 | else | |
3658 | { | |
3659 | char *value; | |
3660 | ||
3661 | value = xmalloc (1 + i - start); | |
3662 | strncpy (value, string + start, i - start); | |
3663 | value [i - start] = '\0'; | |
3664 | ||
3665 | return (value); | |
3666 | } | |
3667 | } | |
3668 | ||
3669 | /* Return non-zero if the characters from SAMPLE are not all valid | |
3670 | characters to be found in the first line of a shell script. We | |
3671 | check up to the first newline, or SAMPLE_LEN, whichever comes first. | |
3672 | All of the characters must be printable or whitespace. */ | |
3673 | ||
3674 | #if !defined (isspace) | |
3675 | #define isspace(c) ((c) == ' ' || (c) == '\t' || (c) == '\n' || (c) == '\f') | |
3676 | #endif | |
3677 | ||
3678 | #if !defined (isprint) | |
3679 | #define isprint(c) (isletter(c) || digit(c) || ispunct(c)) | |
3680 | #endif | |
3681 | ||
3682 | int | |
3683 | check_binary_file (sample, sample_len) | |
3684 | unsigned char *sample; | |
3685 | int sample_len; | |
3686 | { | |
3687 | register int i; | |
3688 | ||
3689 | for (i = 0; i < sample_len; i++) | |
3690 | { | |
3691 | if (sample[i] == '\n') | |
3692 | break; | |
3693 | ||
3694 | if (!isspace (sample[i]) && !isprint (sample[i])) | |
3695 | return (1); | |
3696 | } | |
3697 | return (0); | |
3698 | } |