]>
Commit | Line | Data |
---|---|---|
cce855bc JA |
1 | /* redir.c -- Functions to perform input and output redirection. */ |
2 | ||
3 | /* Copyright (C) 1997 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 | |
bb70624e | 9 | the Free Software Foundation; either version 2, or (at your option) |
cce855bc JA |
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 | |
bb70624e | 19 | Software Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */ |
cce855bc JA |
20 | #include "config.h" |
21 | ||
22 | #if !defined (__GNUC__) && !defined (HAVE_ALLOCA_H) && defined (_AIX) | |
23 | #pragma alloca | |
24 | #endif /* _AIX && RISC6000 && !__GNUC__ */ | |
25 | ||
26 | #include <stdio.h> | |
27 | #include "bashtypes.h" | |
28 | #ifndef _MINIX | |
29 | # include <sys/file.h> | |
30 | #endif | |
31 | #include "filecntl.h" | |
32 | #include "posixstat.h" | |
33 | ||
34 | #if defined (HAVE_UNISTD_H) | |
35 | # include <unistd.h> | |
36 | #endif | |
37 | ||
38 | #include <errno.h> | |
39 | ||
40 | #if !defined (errno) | |
41 | extern int errno; | |
42 | #endif | |
43 | ||
44 | #include "bashansi.h" | |
45 | ||
46 | #include "memalloc.h" | |
47 | #include "shell.h" | |
48 | #include "flags.h" | |
49 | #include "execute_cmd.h" | |
50 | #include "redir.h" | |
51 | ||
52 | #if defined (BUFFERED_INPUT) | |
53 | # include "input.h" | |
54 | #endif | |
55 | ||
56 | extern int posixly_correct; | |
cce855bc JA |
57 | extern REDIRECT *redirection_undo_list; |
58 | extern REDIRECT *exec_redirection_undo_list; | |
59 | ||
60 | /* Static functions defined and used in this file. */ | |
f73dda09 JA |
61 | static void add_undo_close_redirect __P((int)); |
62 | static void add_exec_redirect __P((REDIRECT *)); | |
63 | static int add_undo_redirect __P((int)); | |
64 | static int expandable_redirection_filename __P((REDIRECT *)); | |
65 | static int stdin_redirection __P((enum r_instruction, int)); | |
66 | static int do_redirection_internal __P((REDIRECT *, int, int, int)); | |
67 | ||
68 | static int write_here_document __P((int, WORD_DESC *)); | |
69 | static int here_document_to_fd __P((WORD_DESC *)); | |
70 | ||
71 | static int redir_special_open __P((int, char *, int, int, enum r_instruction)); | |
72 | static int noclobber_open __P((char *, int, int, enum r_instruction)); | |
73 | static int redir_open __P((char *, int, int, enum r_instruction)); | |
cce855bc JA |
74 | |
75 | /* Spare redirector used when translating [N]>&WORD or [N]<&WORD to a new | |
76 | redirection and when creating the redirection undo list. */ | |
77 | static REDIRECTEE rd; | |
78 | ||
79 | /* Set to errno when a here document cannot be created for some reason. | |
80 | Used to print a reasonable error message. */ | |
81 | static int heredoc_errno; | |
82 | ||
83 | void | |
84 | redirection_error (temp, error) | |
85 | REDIRECT *temp; | |
86 | int error; | |
87 | { | |
f73dda09 | 88 | char *filename, *allocname; |
bb70624e | 89 | int oflags; |
cce855bc | 90 | |
f73dda09 JA |
91 | allocname = 0; |
92 | if (temp->redirector < 0) | |
93 | /* This can happen when read_token_word encounters overflow, like in | |
94 | exec 4294967297>x */ | |
95 | filename = "file descriptor out of range"; | |
96 | #ifdef EBADF | |
97 | else if (temp->redirector >= 0 && errno == EBADF) | |
98 | filename = allocname = itos (temp->redirector); | |
99 | #endif | |
100 | else if (expandable_redirection_filename (temp)) | |
cce855bc | 101 | { |
bb70624e JA |
102 | if (posixly_correct && interactive_shell == 0) |
103 | { | |
104 | oflags = temp->redirectee.filename->flags; | |
105 | temp->redirectee.filename->flags |= W_NOGLOB; | |
106 | } | |
f73dda09 | 107 | filename = allocname = redirection_expand (temp->redirectee.filename); |
bb70624e | 108 | if (posixly_correct && interactive_shell == 0) |
28ef6c31 | 109 | temp->redirectee.filename->flags = oflags; |
cce855bc | 110 | if (filename == 0) |
f73dda09 | 111 | filename = temp->redirectee.filename->word; |
cce855bc | 112 | } |
f73dda09 JA |
113 | else if (temp->redirectee.dest < 0) |
114 | filename = "file descriptor out of range"; | |
cce855bc | 115 | else |
f73dda09 | 116 | filename = allocname = itos (temp->redirectee.dest); |
cce855bc JA |
117 | |
118 | switch (error) | |
119 | { | |
120 | case AMBIGUOUS_REDIRECT: | |
121 | internal_error ("%s: ambiguous redirect", filename); | |
122 | break; | |
123 | ||
124 | case NOCLOBBER_REDIRECT: | |
125 | internal_error ("%s: cannot overwrite existing file", filename); | |
126 | break; | |
127 | ||
128 | #if defined (RESTRICTED_SHELL) | |
129 | case RESTRICTED_REDIRECT: | |
130 | internal_error ("%s: restricted: cannot redirect output", filename); | |
131 | break; | |
132 | #endif /* RESTRICTED_SHELL */ | |
133 | ||
134 | case HEREDOC_REDIRECT: | |
135 | internal_error ("cannot create temp file for here document: %s", strerror (heredoc_errno)); | |
136 | break; | |
137 | ||
138 | default: | |
139 | internal_error ("%s: %s", filename, strerror (error)); | |
140 | break; | |
141 | } | |
142 | ||
f73dda09 | 143 | FREE (allocname); |
cce855bc JA |
144 | } |
145 | ||
146 | /* Perform the redirections on LIST. If FOR_REAL, then actually make | |
147 | input and output file descriptors, otherwise just do whatever is | |
148 | neccessary for side effecting. INTERNAL says to remember how to | |
149 | undo the redirections later, if non-zero. If SET_CLEXEC is non-zero, | |
150 | file descriptors opened in do_redirection () have their close-on-exec | |
151 | flag set. */ | |
152 | int | |
153 | do_redirections (list, for_real, internal, set_clexec) | |
154 | REDIRECT *list; | |
155 | int for_real, internal, set_clexec; | |
156 | { | |
157 | int error; | |
158 | REDIRECT *temp; | |
159 | ||
160 | if (internal) | |
161 | { | |
162 | if (redirection_undo_list) | |
163 | { | |
164 | dispose_redirects (redirection_undo_list); | |
165 | redirection_undo_list = (REDIRECT *)NULL; | |
166 | } | |
167 | if (exec_redirection_undo_list) | |
168 | dispose_exec_redirects (); | |
169 | } | |
170 | ||
171 | for (temp = list; temp; temp = temp->next) | |
172 | { | |
173 | error = do_redirection_internal (temp, for_real, internal, set_clexec); | |
174 | if (error) | |
175 | { | |
176 | redirection_error (temp, error); | |
177 | return (error); | |
178 | } | |
179 | } | |
180 | return (0); | |
181 | } | |
182 | ||
183 | /* Return non-zero if the redirection pointed to by REDIRECT has a | |
184 | redirectee.filename that can be expanded. */ | |
185 | static int | |
186 | expandable_redirection_filename (redirect) | |
187 | REDIRECT *redirect; | |
188 | { | |
189 | switch (redirect->instruction) | |
190 | { | |
191 | case r_output_direction: | |
192 | case r_appending_to: | |
193 | case r_input_direction: | |
194 | case r_inputa_direction: | |
195 | case r_err_and_out: | |
196 | case r_input_output: | |
197 | case r_output_force: | |
198 | case r_duplicating_input_word: | |
199 | case r_duplicating_output_word: | |
200 | return 1; | |
201 | ||
202 | default: | |
203 | return 0; | |
204 | } | |
205 | } | |
206 | ||
207 | /* Expand the word in WORD returning a string. If WORD expands to | |
208 | multiple words (or no words), then return NULL. */ | |
209 | char * | |
210 | redirection_expand (word) | |
211 | WORD_DESC *word; | |
212 | { | |
213 | char *result; | |
214 | WORD_LIST *tlist1, *tlist2; | |
bb70624e JA |
215 | WORD_DESC *w; |
216 | ||
217 | w = copy_word (word); | |
218 | if (posixly_correct) | |
219 | w->flags |= W_NOSPLIT; | |
cce855bc | 220 | |
bb70624e | 221 | tlist1 = make_word_list (w, (WORD_LIST *)NULL); |
cce855bc JA |
222 | tlist2 = expand_words_no_vars (tlist1); |
223 | dispose_words (tlist1); | |
224 | ||
225 | if (!tlist2 || tlist2->next) | |
226 | { | |
227 | /* We expanded to no words, or to more than a single word. | |
228 | Dispose of the word list and return NULL. */ | |
229 | if (tlist2) | |
230 | dispose_words (tlist2); | |
231 | return ((char *)NULL); | |
232 | } | |
233 | result = string_list (tlist2); /* XXX savestring (tlist2->word->word)? */ | |
234 | dispose_words (tlist2); | |
235 | return (result); | |
236 | } | |
237 | ||
238 | /* Write the text of the here document pointed to by REDIRECTEE to the file | |
239 | descriptor FD, which is already open to a temp file. Return 0 if the | |
240 | write is successful, otherwise return errno. */ | |
241 | static int | |
242 | write_here_document (fd, redirectee) | |
243 | int fd; | |
244 | WORD_DESC *redirectee; | |
245 | { | |
246 | char *document; | |
247 | int document_len, fd2; | |
248 | FILE *fp; | |
249 | register WORD_LIST *t, *tlist; | |
250 | ||
251 | /* Expand the text if the word that was specified had | |
252 | no quoting. The text that we expand is treated | |
253 | exactly as if it were surrounded by double quotes. */ | |
254 | ||
255 | if (redirectee->flags & W_QUOTED) | |
256 | { | |
257 | document = redirectee->word; | |
258 | document_len = strlen (document); | |
259 | /* Set errno to something reasonable if the write fails. */ | |
260 | if (write (fd, document, document_len) < document_len) | |
261 | { | |
262 | if (errno == 0) | |
263 | errno = ENOSPC; | |
264 | return (errno); | |
265 | } | |
266 | else | |
28ef6c31 | 267 | return 0; |
cce855bc JA |
268 | } |
269 | ||
270 | tlist = expand_string (redirectee->word, Q_HERE_DOCUMENT); | |
271 | if (tlist) | |
272 | { | |
273 | /* Try using buffered I/O (stdio) and writing a word | |
274 | at a time, letting stdio do the work of buffering | |
275 | for us rather than managing our own strings. Most | |
276 | stdios are not particularly fast, however -- this | |
277 | may need to be reconsidered later. */ | |
278 | if ((fd2 = dup (fd)) < 0 || (fp = fdopen (fd2, "w")) == NULL) | |
279 | { | |
280 | if (fd2 >= 0) | |
281 | close (fd2); | |
282 | return (errno); | |
283 | } | |
284 | errno = 0; | |
285 | for (t = tlist; t; t = t->next) | |
286 | { | |
287 | /* This is essentially the body of | |
288 | string_list_internal expanded inline. */ | |
289 | document = t->word->word; | |
290 | document_len = strlen (document); | |
291 | if (t != tlist) | |
292 | putc (' ', fp); /* separator */ | |
293 | fwrite (document, document_len, 1, fp); | |
294 | if (ferror (fp)) | |
295 | { | |
296 | if (errno == 0) | |
297 | errno = ENOSPC; | |
298 | fd2 = errno; | |
299 | fclose(fp); | |
300 | dispose_words (tlist); | |
301 | return (fd2); | |
302 | } | |
303 | } | |
cce855bc | 304 | dispose_words (tlist); |
f73dda09 JA |
305 | if (fclose (fp) != 0) |
306 | { | |
307 | if (errno == 0) | |
308 | errno = ENOSPC; | |
309 | return (errno); | |
310 | } | |
cce855bc JA |
311 | } |
312 | return 0; | |
313 | } | |
314 | ||
315 | /* Create a temporary file holding the text of the here document pointed to | |
316 | by REDIRECTEE, and return a file descriptor open for reading to the temp | |
317 | file. Return -1 on any error, and make sure errno is set appropriately. */ | |
318 | static int | |
319 | here_document_to_fd (redirectee) | |
320 | WORD_DESC *redirectee; | |
321 | { | |
28ef6c31 | 322 | char *filename; |
bb70624e | 323 | int r, fd, fd2; |
cce855bc | 324 | |
28ef6c31 | 325 | fd = sh_mktmpfd ("sh-thd", MT_USERANDOM, &filename); |
cce855bc JA |
326 | |
327 | /* If we failed for some reason other than the file existing, abort */ | |
328 | if (fd < 0) | |
28ef6c31 JA |
329 | { |
330 | FREE (filename); | |
331 | return (fd); | |
332 | } | |
cce855bc JA |
333 | |
334 | errno = r = 0; /* XXX */ | |
335 | /* write_here_document returns 0 on success, errno on failure. */ | |
336 | if (redirectee->word) | |
337 | r = write_here_document (fd, redirectee); | |
338 | ||
cce855bc JA |
339 | if (r) |
340 | { | |
bb70624e | 341 | close (fd); |
cce855bc | 342 | unlink (filename); |
28ef6c31 | 343 | free (filename); |
cce855bc JA |
344 | errno = r; |
345 | return (-1); | |
346 | } | |
347 | ||
bb70624e JA |
348 | /* In an attempt to avoid races, we close the first fd only after opening |
349 | the second. */ | |
cce855bc | 350 | /* Make the document really temporary. Also make it the input. */ |
bb70624e | 351 | fd2 = open (filename, O_RDONLY, 0600); |
cce855bc | 352 | |
bb70624e | 353 | if (fd2 < 0) |
cce855bc JA |
354 | { |
355 | r = errno; | |
356 | unlink (filename); | |
28ef6c31 | 357 | free (filename); |
bb70624e | 358 | close (fd); |
cce855bc JA |
359 | errno = r; |
360 | return -1; | |
361 | } | |
362 | ||
bb70624e | 363 | close (fd); |
cce855bc JA |
364 | if (unlink (filename) < 0) |
365 | { | |
366 | r = errno; | |
28ef6c31 JA |
367 | #if defined (__CYGWIN__) |
368 | /* Under CygWin 1.1.0, the unlink will fail if the file is | |
369 | open. This hack will allow the previous action of silently | |
370 | ignoring the error, but will still leave the file there. This | |
371 | needs some kind of magic. */ | |
372 | if (r == EACCES) | |
373 | return (fd2); | |
374 | #endif /* __CYGWIN__ */ | |
bb70624e | 375 | close (fd2); |
28ef6c31 | 376 | free (filename); |
cce855bc JA |
377 | errno = r; |
378 | return (-1); | |
379 | } | |
380 | ||
28ef6c31 | 381 | free (filename); |
bb70624e | 382 | return (fd2); |
cce855bc JA |
383 | } |
384 | ||
bb70624e JA |
385 | #define RF_DEVFD 1 |
386 | #define RF_DEVSTDERR 2 | |
387 | #define RF_DEVSTDIN 3 | |
388 | #define RF_DEVSTDOUT 4 | |
389 | #define RF_DEVTCP 5 | |
390 | #define RF_DEVUDP 6 | |
391 | ||
392 | /* A list of pattern/value pairs for filenames that the redirection | |
393 | code handles specially. */ | |
394 | static STRING_INT_ALIST _redir_special_filenames[] = { | |
395 | #if !defined (HAVE_DEV_FD) | |
396 | { "/dev/fd/[0-9]*", RF_DEVFD }, | |
397 | #endif | |
398 | #if !defined (HAVE_DEV_STDIN) | |
399 | { "/dev/stderr", RF_DEVSTDERR }, | |
400 | { "/dev/stdin", RF_DEVSTDIN }, | |
401 | { "/dev/stdout", RF_DEVSTDOUT }, | |
402 | #endif | |
403 | #if defined (NETWORK_REDIRECTIONS) | |
404 | { "/dev/tcp/*/*", RF_DEVTCP }, | |
405 | { "/dev/udp/*/*", RF_DEVUDP }, | |
406 | #endif | |
407 | { (char *)NULL, -1 } | |
408 | }; | |
409 | ||
410 | static int | |
411 | redir_special_open (spec, filename, flags, mode, ri) | |
412 | int spec; | |
413 | char *filename; | |
414 | int flags, mode; | |
415 | enum r_instruction ri; | |
416 | { | |
417 | int fd; | |
f73dda09 | 418 | #if !defined (HAVE_DEV_FD) |
bb70624e | 419 | long lfd; |
f73dda09 | 420 | #endif |
bb70624e JA |
421 | |
422 | fd = -1; | |
423 | switch (spec) | |
424 | { | |
425 | #if !defined (HAVE_DEV_FD) | |
426 | case RF_DEVFD: | |
f73dda09 JA |
427 | if (all_digits (filename+8) && legal_number (filename+8, &lfd) && lfd == (int)lfd) |
428 | { | |
429 | fd = lfd; | |
430 | fd = fcntl (fd, F_DUPFD, 10); | |
431 | } | |
bb70624e JA |
432 | else |
433 | fd = AMBIGUOUS_REDIRECT; | |
434 | break; | |
435 | #endif | |
436 | ||
437 | #if !defined (HAVE_DEV_STDIN) | |
438 | case RF_DEVSTDIN: | |
439 | fd = fcntl (0, F_DUPFD, 10); | |
440 | break; | |
441 | case RF_DEVSTDOUT: | |
442 | fd = fcntl (1, F_DUPFD, 10); | |
443 | break; | |
444 | case RF_DEVSTDERR: | |
445 | fd = fcntl (2, F_DUPFD, 10); | |
446 | break; | |
447 | #endif | |
448 | ||
449 | #if defined (NETWORK_REDIRECTIONS) | |
450 | case RF_DEVTCP: | |
451 | case RF_DEVUDP: | |
452 | #if defined (HAVE_NETWORK) | |
453 | fd = netopen (filename); | |
454 | #else | |
455 | internal_warning ("/dev/(tcp|udp)/host/port not supported without networking"); | |
456 | fd = open (filename, flags, mode); | |
457 | #endif | |
458 | break; | |
459 | #endif /* NETWORK_REDIRECTIONS */ | |
460 | } | |
461 | ||
462 | return fd; | |
463 | } | |
464 | ||
cce855bc JA |
465 | /* Open FILENAME with FLAGS in noclobber mode, hopefully avoiding most |
466 | race conditions and avoiding the problem where the file is replaced | |
467 | between the stat(2) and open(2). */ | |
468 | static int | |
bb70624e | 469 | noclobber_open (filename, flags, mode, ri) |
cce855bc | 470 | char *filename; |
bb70624e | 471 | int flags, mode; |
cce855bc JA |
472 | enum r_instruction ri; |
473 | { | |
474 | int r, fd; | |
475 | struct stat finfo, finfo2; | |
476 | ||
477 | /* If the file exists and is a regular file, return an error | |
478 | immediately. */ | |
479 | r = stat (filename, &finfo); | |
480 | if (r == 0 && (S_ISREG (finfo.st_mode))) | |
481 | return (NOCLOBBER_REDIRECT); | |
482 | ||
483 | /* If the file was not present (r != 0), make sure we open it | |
484 | exclusively so that if it is created before we open it, our open | |
485 | will fail. Make sure that we do not truncate an existing file. | |
486 | Note that we don't turn on O_EXCL unless the stat failed -- if | |
487 | the file was not a regular file, we leave O_EXCL off. */ | |
488 | flags &= ~O_TRUNC; | |
489 | if (r != 0) | |
490 | { | |
bb70624e | 491 | fd = open (filename, flags|O_EXCL, mode); |
cce855bc JA |
492 | return ((fd < 0 && errno == EEXIST) ? NOCLOBBER_REDIRECT : fd); |
493 | } | |
bb70624e | 494 | fd = open (filename, flags, mode); |
cce855bc JA |
495 | |
496 | /* If the open failed, return the file descriptor right away. */ | |
497 | if (fd < 0) | |
498 | return (errno == EEXIST ? NOCLOBBER_REDIRECT : fd); | |
499 | ||
500 | /* OK, the open succeeded, but the file may have been changed from a | |
501 | non-regular file to a regular file between the stat and the open. | |
502 | We are assuming that the O_EXCL open handles the case where FILENAME | |
503 | did not exist and is symlinked to an existing file between the stat | |
504 | and open. */ | |
505 | ||
506 | /* If we can open it and fstat the file descriptor, and neither check | |
507 | revealed that it was a regular file, and the file has not been replaced, | |
508 | return the file descriptor. */ | |
509 | if ((fstat (fd, &finfo2) == 0) && (S_ISREG (finfo2.st_mode) == 0) && | |
510 | r == 0 && (S_ISREG (finfo.st_mode) == 0) && | |
511 | same_file (filename, filename, &finfo, &finfo2)) | |
512 | return fd; | |
513 | ||
514 | /* The file has been replaced. badness. */ | |
515 | close (fd); | |
516 | errno = EEXIST; | |
517 | return (NOCLOBBER_REDIRECT); | |
518 | } | |
519 | ||
bb70624e JA |
520 | static int |
521 | redir_open (filename, flags, mode, ri) | |
522 | char *filename; | |
523 | int flags, mode; | |
524 | enum r_instruction ri; | |
525 | { | |
526 | int fd, r; | |
527 | ||
528 | r = find_string_in_alist (filename, _redir_special_filenames, 1); | |
529 | if (r >= 0) | |
530 | return (redir_special_open (r, filename, flags, mode, ri)); | |
531 | ||
532 | /* If we are in noclobber mode, you are not allowed to overwrite | |
533 | existing files. Check before opening. */ | |
28ef6c31 | 534 | if (noclobber && CLOBBERING_REDIRECT (ri)) |
bb70624e JA |
535 | { |
536 | fd = noclobber_open (filename, flags, mode, ri); | |
537 | if (fd == NOCLOBBER_REDIRECT) | |
538 | return (NOCLOBBER_REDIRECT); | |
539 | } | |
540 | else | |
541 | { | |
542 | fd = open (filename, flags, mode); | |
543 | #if defined (AFS) | |
544 | if ((fd < 0) && (errno == EACCES)) | |
545 | fd = open (filename, flags & ~O_CREAT, mode); | |
546 | #endif /* AFS */ | |
547 | } | |
548 | ||
549 | return fd; | |
550 | } | |
551 | ||
cce855bc JA |
552 | /* Do the specific redirection requested. Returns errno or one of the |
553 | special redirection errors (*_REDIRECT) in case of error, 0 on success. | |
554 | If FOR_REAL is zero, then just do whatever is neccessary to produce the | |
555 | appropriate side effects. REMEMBERING, if non-zero, says to remember | |
556 | how to undo each redirection. If SET_CLEXEC is non-zero, then | |
557 | we set all file descriptors > 2 that we open to be close-on-exec. */ | |
558 | static int | |
559 | do_redirection_internal (redirect, for_real, remembering, set_clexec) | |
560 | REDIRECT *redirect; | |
561 | int for_real, remembering, set_clexec; | |
562 | { | |
563 | WORD_DESC *redirectee; | |
bb70624e | 564 | int redir_fd, fd, redirector, r, oflags; |
f73dda09 | 565 | long lfd; |
cce855bc JA |
566 | char *redirectee_word; |
567 | enum r_instruction ri; | |
568 | REDIRECT *new_redirect; | |
569 | ||
570 | redirectee = redirect->redirectee.filename; | |
571 | redir_fd = redirect->redirectee.dest; | |
572 | redirector = redirect->redirector; | |
573 | ri = redirect->instruction; | |
574 | ||
575 | if (ri == r_duplicating_input_word || ri == r_duplicating_output_word) | |
576 | { | |
577 | /* We have [N]>&WORD or [N]<&WORD. Expand WORD, then translate | |
578 | the redirection into a new one and continue. */ | |
579 | redirectee_word = redirection_expand (redirectee); | |
580 | ||
581 | if (redirectee_word == 0) | |
582 | return (AMBIGUOUS_REDIRECT); | |
583 | else if (redirectee_word[0] == '-' && redirectee_word[1] == '\0') | |
584 | { | |
f73dda09 | 585 | rd.dest = 0; |
cce855bc JA |
586 | new_redirect = make_redirection (redirector, r_close_this, rd); |
587 | } | |
588 | else if (all_digits (redirectee_word)) | |
589 | { | |
f73dda09 JA |
590 | if (legal_number (redirectee_word, &lfd) && (int)lfd == lfd) |
591 | rd.dest = lfd; | |
cce855bc | 592 | else |
f73dda09 JA |
593 | rd.dest = -1; /* XXX */ |
594 | new_redirect = make_redirection (redirector, | |
595 | (ri == r_duplicating_input_word | |
596 | ? r_duplicating_input | |
597 | : r_duplicating_output), | |
598 | rd); | |
cce855bc JA |
599 | } |
600 | else if (ri == r_duplicating_output_word && redirector == 1) | |
601 | { | |
28ef6c31 JA |
602 | rd.filename = make_bare_word (redirectee_word); |
603 | new_redirect = make_redirection (1, r_err_and_out, rd); | |
cce855bc JA |
604 | } |
605 | else | |
606 | { | |
607 | free (redirectee_word); | |
608 | return (AMBIGUOUS_REDIRECT); | |
609 | } | |
610 | ||
611 | free (redirectee_word); | |
612 | ||
613 | /* Set up the variables needed by the rest of the function from the | |
614 | new redirection. */ | |
615 | if (new_redirect->instruction == r_err_and_out) | |
616 | { | |
617 | char *alloca_hack; | |
618 | ||
619 | /* Copy the word without allocating any memory that must be | |
620 | explicitly freed. */ | |
621 | redirectee = (WORD_DESC *)alloca (sizeof (WORD_DESC)); | |
622 | xbcopy ((char *)new_redirect->redirectee.filename, | |
623 | (char *)redirectee, sizeof (WORD_DESC)); | |
624 | ||
625 | alloca_hack = (char *) | |
626 | alloca (1 + strlen (new_redirect->redirectee.filename->word)); | |
627 | redirectee->word = alloca_hack; | |
628 | strcpy (redirectee->word, new_redirect->redirectee.filename->word); | |
629 | } | |
630 | else | |
631 | /* It's guaranteed to be an integer, and shouldn't be freed. */ | |
632 | redirectee = new_redirect->redirectee.filename; | |
633 | ||
634 | redir_fd = new_redirect->redirectee.dest; | |
635 | redirector = new_redirect->redirector; | |
636 | ri = new_redirect->instruction; | |
637 | ||
638 | /* Overwrite the flags element of the old redirect with the new value. */ | |
639 | redirect->flags = new_redirect->flags; | |
640 | dispose_redirects (new_redirect); | |
641 | } | |
642 | ||
643 | switch (ri) | |
644 | { | |
645 | case r_output_direction: | |
646 | case r_appending_to: | |
647 | case r_input_direction: | |
648 | case r_inputa_direction: | |
649 | case r_err_and_out: /* command &>filename */ | |
650 | case r_input_output: | |
651 | case r_output_force: | |
bb70624e | 652 | if (posixly_correct && interactive_shell == 0) |
28ef6c31 JA |
653 | { |
654 | oflags = redirectee->flags; | |
655 | redirectee->flags |= W_NOGLOB; | |
656 | } | |
cce855bc | 657 | redirectee_word = redirection_expand (redirectee); |
bb70624e JA |
658 | if (posixly_correct && interactive_shell == 0) |
659 | redirectee->flags = oflags; | |
cce855bc JA |
660 | |
661 | if (redirectee_word == 0) | |
662 | return (AMBIGUOUS_REDIRECT); | |
663 | ||
664 | #if defined (RESTRICTED_SHELL) | |
665 | if (restricted && (WRITE_REDIRECT (ri))) | |
666 | { | |
667 | free (redirectee_word); | |
668 | return (RESTRICTED_REDIRECT); | |
669 | } | |
670 | #endif /* RESTRICTED_SHELL */ | |
671 | ||
bb70624e | 672 | fd = redir_open (redirectee_word, redirect->flags, 0666, ri); |
cce855bc JA |
673 | free (redirectee_word); |
674 | ||
bb70624e | 675 | if (fd == NOCLOBBER_REDIRECT) |
28ef6c31 | 676 | return (fd); |
bb70624e | 677 | |
cce855bc JA |
678 | if (fd < 0) |
679 | return (errno); | |
680 | ||
681 | if (for_real) | |
682 | { | |
683 | if (remembering) | |
f73dda09 JA |
684 | { |
685 | /* Only setup to undo it if the thing to undo is active. */ | |
686 | if ((fd != redirector) && (fcntl (redirector, F_GETFD, 0) != -1)) | |
687 | add_undo_redirect (redirector); | |
688 | else | |
689 | add_undo_close_redirect (redirector); | |
690 | } | |
cce855bc JA |
691 | |
692 | #if defined (BUFFERED_INPUT) | |
693 | check_bash_input (redirector); | |
694 | #endif | |
695 | ||
696 | if ((fd != redirector) && (dup2 (fd, redirector) < 0)) | |
697 | return (errno); | |
698 | ||
699 | #if defined (BUFFERED_INPUT) | |
700 | /* Do not change the buffered stream for an implicit redirection | |
701 | of /dev/null to fd 0 for asynchronous commands without job | |
702 | control (r_inputa_direction). */ | |
703 | if (ri == r_input_direction || ri == r_input_output) | |
704 | duplicate_buffered_stream (fd, redirector); | |
705 | #endif /* BUFFERED_INPUT */ | |
706 | ||
707 | /* | |
708 | * If we're remembering, then this is the result of a while, for | |
709 | * or until loop with a loop redirection, or a function/builtin | |
710 | * executing in the parent shell with a redirection. In the | |
711 | * function/builtin case, we want to set all file descriptors > 2 | |
712 | * to be close-on-exec to duplicate the effect of the old | |
713 | * for i = 3 to NOFILE close(i) loop. In the case of the loops, | |
714 | * both sh and ksh leave the file descriptors open across execs. | |
715 | * The Posix standard mentions only the exec builtin. | |
716 | */ | |
717 | if (set_clexec && (redirector > 2)) | |
718 | SET_CLOSE_ON_EXEC (redirector); | |
719 | } | |
720 | ||
721 | if (fd != redirector) | |
722 | { | |
723 | #if defined (BUFFERED_INPUT) | |
724 | if (INPUT_REDIRECT (ri)) | |
725 | close_buffered_fd (fd); | |
726 | else | |
727 | #endif /* !BUFFERED_INPUT */ | |
728 | close (fd); /* Don't close what we just opened! */ | |
729 | } | |
730 | ||
731 | /* If we are hacking both stdout and stderr, do the stderr | |
732 | redirection here. */ | |
733 | if (ri == r_err_and_out) | |
734 | { | |
735 | if (for_real) | |
736 | { | |
737 | if (remembering) | |
738 | add_undo_redirect (2); | |
739 | if (dup2 (1, 2) < 0) | |
740 | return (errno); | |
741 | } | |
742 | } | |
743 | break; | |
744 | ||
745 | case r_reading_until: | |
746 | case r_deblank_reading_until: | |
747 | /* REDIRECTEE is a pointer to a WORD_DESC containing the text of | |
748 | the new input. Place it in a temporary file. */ | |
749 | if (redirectee) | |
750 | { | |
751 | fd = here_document_to_fd (redirectee); | |
752 | ||
753 | if (fd < 0) | |
754 | { | |
755 | heredoc_errno = errno; | |
756 | return (HEREDOC_REDIRECT); | |
757 | } | |
758 | ||
759 | if (for_real) | |
760 | { | |
761 | if (remembering) | |
f73dda09 JA |
762 | { |
763 | /* Only setup to undo it if the thing to undo is active. */ | |
764 | if ((fd != redirector) && (fcntl (redirector, F_GETFD, 0) != -1)) | |
765 | add_undo_redirect (redirector); | |
766 | else | |
767 | add_undo_close_redirect (redirector); | |
768 | } | |
cce855bc JA |
769 | |
770 | #if defined (BUFFERED_INPUT) | |
771 | check_bash_input (redirector); | |
772 | #endif | |
773 | if (fd != redirector && dup2 (fd, redirector) < 0) | |
774 | { | |
775 | r = errno; | |
776 | close (fd); | |
777 | return (r); | |
778 | } | |
779 | ||
780 | #if defined (BUFFERED_INPUT) | |
781 | duplicate_buffered_stream (fd, redirector); | |
782 | #endif | |
783 | ||
784 | if (set_clexec && (redirector > 2)) | |
785 | SET_CLOSE_ON_EXEC (redirector); | |
786 | } | |
787 | ||
bb70624e | 788 | if (fd != redirector) |
cce855bc | 789 | #if defined (BUFFERED_INPUT) |
bb70624e | 790 | close_buffered_fd (fd); |
cce855bc | 791 | #else |
bb70624e | 792 | close (fd); |
cce855bc JA |
793 | #endif |
794 | } | |
795 | break; | |
796 | ||
797 | case r_duplicating_input: | |
798 | case r_duplicating_output: | |
799 | if (for_real && (redir_fd != redirector)) | |
800 | { | |
801 | if (remembering) | |
f73dda09 JA |
802 | { |
803 | /* Only setup to undo it if the thing to undo is active. */ | |
804 | if (fcntl (redirector, F_GETFD, 0) != -1) | |
805 | add_undo_redirect (redirector); | |
806 | else | |
807 | add_undo_close_redirect (redirector); | |
808 | } | |
cce855bc JA |
809 | |
810 | #if defined (BUFFERED_INPUT) | |
811 | check_bash_input (redirector); | |
812 | #endif | |
813 | /* This is correct. 2>&1 means dup2 (1, 2); */ | |
814 | if (dup2 (redir_fd, redirector) < 0) | |
815 | return (errno); | |
816 | ||
817 | #if defined (BUFFERED_INPUT) | |
818 | if (ri == r_duplicating_input) | |
819 | duplicate_buffered_stream (redir_fd, redirector); | |
820 | #endif /* BUFFERED_INPUT */ | |
821 | ||
822 | /* First duplicate the close-on-exec state of redirectee. dup2 | |
823 | leaves the flag unset on the new descriptor, which means it | |
824 | stays open. Only set the close-on-exec bit for file descriptors | |
825 | greater than 2 in any case, since 0-2 should always be open | |
826 | unless closed by something like `exec 2<&-'. */ | |
827 | /* if ((already_set || set_unconditionally) && (ok_to_set)) | |
828 | set_it () */ | |
829 | if (((fcntl (redir_fd, F_GETFD, 0) == 1) || set_clexec) && | |
830 | (redirector > 2)) | |
831 | SET_CLOSE_ON_EXEC (redirector); | |
832 | } | |
833 | break; | |
834 | ||
835 | case r_close_this: | |
836 | if (for_real) | |
837 | { | |
838 | if (remembering && (fcntl (redirector, F_GETFD, 0) != -1)) | |
839 | add_undo_redirect (redirector); | |
840 | ||
841 | #if defined (BUFFERED_INPUT) | |
842 | check_bash_input (redirector); | |
843 | close_buffered_fd (redirector); | |
844 | #else /* !BUFFERED_INPUT */ | |
845 | close (redirector); | |
846 | #endif /* !BUFFERED_INPUT */ | |
847 | } | |
848 | break; | |
849 | ||
850 | case r_duplicating_input_word: | |
851 | case r_duplicating_output_word: | |
852 | break; | |
853 | } | |
854 | return (0); | |
855 | } | |
856 | ||
857 | #define SHELL_FD_BASE 10 | |
858 | ||
859 | /* Remember the file descriptor associated with the slot FD, | |
860 | on REDIRECTION_UNDO_LIST. Note that the list will be reversed | |
861 | before it is executed. Any redirections that need to be undone | |
862 | even if REDIRECTION_UNDO_LIST is discarded by the exec builtin | |
863 | are also saved on EXEC_REDIRECTION_UNDO_LIST. */ | |
864 | static int | |
865 | add_undo_redirect (fd) | |
866 | int fd; | |
867 | { | |
868 | int new_fd, clexec_flag; | |
869 | REDIRECT *new_redirect, *closer, *dummy_redirect; | |
870 | ||
871 | new_fd = fcntl (fd, F_DUPFD, SHELL_FD_BASE); | |
872 | ||
873 | if (new_fd < 0) | |
874 | { | |
28ef6c31 | 875 | sys_error ("redirection error: cannot duplicate fd"); |
cce855bc JA |
876 | return (-1); |
877 | } | |
878 | ||
879 | clexec_flag = fcntl (fd, F_GETFD, 0); | |
880 | ||
f73dda09 | 881 | rd.dest = 0; |
cce855bc JA |
882 | closer = make_redirection (new_fd, r_close_this, rd); |
883 | dummy_redirect = copy_redirects (closer); | |
884 | ||
f73dda09 | 885 | rd.dest = new_fd; |
28ef6c31 JA |
886 | if (fd == 0) |
887 | new_redirect = make_redirection (fd, r_duplicating_input, rd); | |
888 | else | |
889 | new_redirect = make_redirection (fd, r_duplicating_output, rd); | |
cce855bc JA |
890 | new_redirect->next = closer; |
891 | ||
892 | closer->next = redirection_undo_list; | |
893 | redirection_undo_list = new_redirect; | |
894 | ||
895 | /* Save redirections that need to be undone even if the undo list | |
896 | is thrown away by the `exec' builtin. */ | |
897 | add_exec_redirect (dummy_redirect); | |
898 | ||
899 | /* File descriptors used only for saving others should always be | |
900 | marked close-on-exec. Unfortunately, we have to preserve the | |
901 | close-on-exec state of the file descriptor we are saving, since | |
902 | fcntl (F_DUPFD) sets the new file descriptor to remain open | |
903 | across execs. If, however, the file descriptor whose state we | |
904 | are saving is <= 2, we can just set the close-on-exec flag, | |
905 | because file descriptors 0-2 should always be open-on-exec, | |
906 | and the restore above in do_redirection() will take care of it. */ | |
907 | if (clexec_flag || fd < 3) | |
908 | SET_CLOSE_ON_EXEC (new_fd); | |
909 | ||
910 | return (0); | |
911 | } | |
912 | ||
913 | /* Set up to close FD when we are finished with the current command | |
914 | and its redirections. */ | |
915 | static void | |
916 | add_undo_close_redirect (fd) | |
917 | int fd; | |
918 | { | |
919 | REDIRECT *closer; | |
920 | ||
f73dda09 | 921 | rd.dest = 0; |
cce855bc JA |
922 | closer = make_redirection (fd, r_close_this, rd); |
923 | closer->next = redirection_undo_list; | |
924 | redirection_undo_list = closer; | |
925 | } | |
926 | ||
927 | static void | |
928 | add_exec_redirect (dummy_redirect) | |
929 | REDIRECT *dummy_redirect; | |
930 | { | |
931 | dummy_redirect->next = exec_redirection_undo_list; | |
932 | exec_redirection_undo_list = dummy_redirect; | |
933 | } | |
934 | ||
bb70624e JA |
935 | /* Return 1 if the redirection specified by RI and REDIRECTOR alters the |
936 | standard input. */ | |
937 | static int | |
938 | stdin_redirection (ri, redirector) | |
939 | enum r_instruction ri; | |
940 | int redirector; | |
941 | { | |
942 | switch (ri) | |
943 | { | |
944 | case r_input_direction: | |
945 | case r_inputa_direction: | |
946 | case r_input_output: | |
947 | case r_reading_until: | |
948 | case r_deblank_reading_until: | |
949 | return (1); | |
950 | case r_duplicating_input: | |
951 | case r_duplicating_input_word: | |
952 | case r_close_this: | |
953 | return (redirector == 0); | |
954 | case r_output_direction: | |
955 | case r_appending_to: | |
956 | case r_duplicating_output: | |
957 | case r_err_and_out: | |
958 | case r_output_force: | |
959 | case r_duplicating_output_word: | |
960 | return (0); | |
961 | } | |
962 | return (0); | |
963 | } | |
964 | ||
cce855bc JA |
965 | /* Return non-zero if any of the redirections in REDIRS alter the standard |
966 | input. */ | |
967 | int | |
968 | stdin_redirects (redirs) | |
969 | REDIRECT *redirs; | |
970 | { | |
971 | REDIRECT *rp; | |
972 | int n; | |
973 | ||
974 | for (n = 0, rp = redirs; rp; rp = rp->next) | |
bb70624e | 975 | n += stdin_redirection (rp->instruction, rp->redirector); |
cce855bc JA |
976 | return n; |
977 | } |