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Commit | Line | Data |
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cce855bc JA |
1 | /* redir.c -- Functions to perform input and output redirection. */ |
2 | ||
3185942a | 3 | /* Copyright (C) 1997-2009 Free Software Foundation, Inc. |
cce855bc JA |
4 | |
5 | This file is part of GNU Bash, the Bourne Again SHell. | |
6 | ||
3185942a JA |
7 | Bash is free software: you can redistribute it and/or modify |
8 | it under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation, either version 3 of the License, or | |
10 | (at your option) any later version. | |
cce855bc | 11 | |
3185942a JA |
12 | Bash is distributed in the hope that it will be useful, |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
cce855bc JA |
16 | |
17 | You should have received a copy of the GNU General Public License | |
3185942a JA |
18 | along with Bash. If not, see <http://www.gnu.org/licenses/>. |
19 | */ | |
20 | ||
cce855bc JA |
21 | #include "config.h" |
22 | ||
23 | #if !defined (__GNUC__) && !defined (HAVE_ALLOCA_H) && defined (_AIX) | |
24 | #pragma alloca | |
25 | #endif /* _AIX && RISC6000 && !__GNUC__ */ | |
26 | ||
27 | #include <stdio.h> | |
28 | #include "bashtypes.h" | |
b80f6443 | 29 | #if !defined (_MINIX) && defined (HAVE_SYS_FILE_H) |
cce855bc JA |
30 | # include <sys/file.h> |
31 | #endif | |
32 | #include "filecntl.h" | |
33 | #include "posixstat.h" | |
34 | ||
35 | #if defined (HAVE_UNISTD_H) | |
36 | # include <unistd.h> | |
37 | #endif | |
38 | ||
39 | #include <errno.h> | |
40 | ||
41 | #if !defined (errno) | |
42 | extern int errno; | |
43 | #endif | |
44 | ||
45 | #include "bashansi.h" | |
b80f6443 | 46 | #include "bashintl.h" |
cce855bc | 47 | #include "memalloc.h" |
3185942a JA |
48 | |
49 | #define NEED_FPURGE_DECL | |
50 | ||
cce855bc JA |
51 | #include "shell.h" |
52 | #include "flags.h" | |
53 | #include "execute_cmd.h" | |
54 | #include "redir.h" | |
55 | ||
56 | #if defined (BUFFERED_INPUT) | |
57 | # include "input.h" | |
58 | #endif | |
59 | ||
3185942a JA |
60 | #define SHELL_FD_BASE 10 |
61 | ||
b80f6443 JA |
62 | int expanding_redir; |
63 | ||
cce855bc | 64 | extern int posixly_correct; |
cce855bc JA |
65 | extern REDIRECT *redirection_undo_list; |
66 | extern REDIRECT *exec_redirection_undo_list; | |
67 | ||
68 | /* Static functions defined and used in this file. */ | |
f73dda09 JA |
69 | static void add_undo_close_redirect __P((int)); |
70 | static void add_exec_redirect __P((REDIRECT *)); | |
3185942a | 71 | static int add_undo_redirect __P((int, enum r_instruction, int)); |
f73dda09 JA |
72 | static int expandable_redirection_filename __P((REDIRECT *)); |
73 | static int stdin_redirection __P((enum r_instruction, int)); | |
3185942a | 74 | static int undoablefd __P((int)); |
b80f6443 | 75 | static int do_redirection_internal __P((REDIRECT *, int)); |
f73dda09 JA |
76 | |
77 | static int write_here_document __P((int, WORD_DESC *)); | |
7117c2d2 JA |
78 | static int write_here_string __P((int, WORD_DESC *)); |
79 | static int here_document_to_fd __P((WORD_DESC *, enum r_instruction)); | |
f73dda09 JA |
80 | |
81 | static int redir_special_open __P((int, char *, int, int, enum r_instruction)); | |
82 | static int noclobber_open __P((char *, int, int, enum r_instruction)); | |
83 | static int redir_open __P((char *, int, int, enum r_instruction)); | |
cce855bc | 84 | |
0001803f CR |
85 | static int redir_varassign __P((REDIRECT *, int)); |
86 | static int redir_varvalue __P((REDIRECT *)); | |
87 | ||
7117c2d2 JA |
88 | /* Spare redirector used when translating [N]>&WORD[-] or [N]<&WORD[-] to |
89 | a new redirection and when creating the redirection undo list. */ | |
cce855bc JA |
90 | static REDIRECTEE rd; |
91 | ||
92 | /* Set to errno when a here document cannot be created for some reason. | |
93 | Used to print a reasonable error message. */ | |
94 | static int heredoc_errno; | |
95 | ||
96 | void | |
97 | redirection_error (temp, error) | |
98 | REDIRECT *temp; | |
99 | int error; | |
100 | { | |
f73dda09 | 101 | char *filename, *allocname; |
bb70624e | 102 | int oflags; |
cce855bc | 103 | |
f73dda09 | 104 | allocname = 0; |
0001803f CR |
105 | if (temp->rflags & REDIR_VARASSIGN) |
106 | filename = savestring (temp->redirector.filename->word); | |
107 | else if (temp->redirector.dest < 0) | |
f73dda09 JA |
108 | /* This can happen when read_token_word encounters overflow, like in |
109 | exec 4294967297>x */ | |
b80f6443 | 110 | filename = _("file descriptor out of range"); |
f73dda09 | 111 | #ifdef EBADF |
3185942a | 112 | /* This error can never involve NOCLOBBER */ |
0001803f | 113 | else if (error != NOCLOBBER_REDIRECT && temp->redirector.dest >= 0 && error == EBADF) |
7117c2d2 JA |
114 | { |
115 | /* If we're dealing with two file descriptors, we have to guess about | |
116 | which one is invalid; in the cases of r_{duplicating,move}_input and | |
117 | r_{duplicating,move}_output we're here because dup2() failed. */ | |
118 | switch (temp->instruction) | |
119 | { | |
120 | case r_duplicating_input: | |
121 | case r_duplicating_output: | |
122 | case r_move_input: | |
123 | case r_move_output: | |
124 | filename = allocname = itos (temp->redirectee.dest); | |
125 | break; | |
0001803f CR |
126 | case r_duplicating_input_word: |
127 | if (temp->redirector.dest == 0) /* Guess */ | |
128 | filename = temp->redirectee.filename->word; /* XXX */ | |
129 | else | |
130 | filename = allocname = itos (temp->redirector.dest); | |
131 | break; | |
132 | case r_duplicating_output_word: | |
133 | if (temp->redirector.dest == 1) /* Guess */ | |
134 | filename = temp->redirectee.filename->word; /* XXX */ | |
135 | else | |
136 | filename = allocname = itos (temp->redirector.dest); | |
137 | break; | |
7117c2d2 | 138 | default: |
0001803f | 139 | filename = allocname = itos (temp->redirector.dest); |
7117c2d2 JA |
140 | break; |
141 | } | |
142 | } | |
f73dda09 JA |
143 | #endif |
144 | else if (expandable_redirection_filename (temp)) | |
cce855bc | 145 | { |
0001803f | 146 | expandable_filename: |
bb70624e JA |
147 | if (posixly_correct && interactive_shell == 0) |
148 | { | |
149 | oflags = temp->redirectee.filename->flags; | |
150 | temp->redirectee.filename->flags |= W_NOGLOB; | |
151 | } | |
f73dda09 | 152 | filename = allocname = redirection_expand (temp->redirectee.filename); |
bb70624e | 153 | if (posixly_correct && interactive_shell == 0) |
28ef6c31 | 154 | temp->redirectee.filename->flags = oflags; |
cce855bc | 155 | if (filename == 0) |
f73dda09 | 156 | filename = temp->redirectee.filename->word; |
cce855bc | 157 | } |
f73dda09 JA |
158 | else if (temp->redirectee.dest < 0) |
159 | filename = "file descriptor out of range"; | |
cce855bc | 160 | else |
f73dda09 | 161 | filename = allocname = itos (temp->redirectee.dest); |
cce855bc JA |
162 | |
163 | switch (error) | |
164 | { | |
165 | case AMBIGUOUS_REDIRECT: | |
b80f6443 | 166 | internal_error (_("%s: ambiguous redirect"), filename); |
cce855bc JA |
167 | break; |
168 | ||
169 | case NOCLOBBER_REDIRECT: | |
b80f6443 | 170 | internal_error (_("%s: cannot overwrite existing file"), filename); |
cce855bc JA |
171 | break; |
172 | ||
173 | #if defined (RESTRICTED_SHELL) | |
174 | case RESTRICTED_REDIRECT: | |
b80f6443 | 175 | internal_error (_("%s: restricted: cannot redirect output"), filename); |
cce855bc JA |
176 | break; |
177 | #endif /* RESTRICTED_SHELL */ | |
178 | ||
179 | case HEREDOC_REDIRECT: | |
3185942a | 180 | internal_error (_("cannot create temp file for here-document: %s"), strerror (heredoc_errno)); |
cce855bc JA |
181 | break; |
182 | ||
0001803f CR |
183 | case BADVAR_REDIRECT: |
184 | internal_error (_("%s: cannot assign fd to variable"), filename); | |
185 | break; | |
186 | ||
cce855bc JA |
187 | default: |
188 | internal_error ("%s: %s", filename, strerror (error)); | |
189 | break; | |
190 | } | |
191 | ||
f73dda09 | 192 | FREE (allocname); |
cce855bc JA |
193 | } |
194 | ||
b80f6443 JA |
195 | /* Perform the redirections on LIST. If flags & RX_ACTIVE, then actually |
196 | make input and output file descriptors, otherwise just do whatever is | |
197 | neccessary for side effecting. flags & RX_UNDOABLE says to remember | |
198 | how to undo the redirections later, if non-zero. If flags & RX_CLEXEC | |
199 | is non-zero, file descriptors opened in do_redirection () have their | |
200 | close-on-exec flag set. */ | |
cce855bc | 201 | int |
b80f6443 | 202 | do_redirections (list, flags) |
cce855bc | 203 | REDIRECT *list; |
b80f6443 | 204 | int flags; |
cce855bc JA |
205 | { |
206 | int error; | |
207 | REDIRECT *temp; | |
208 | ||
b80f6443 | 209 | if (flags & RX_UNDOABLE) |
cce855bc JA |
210 | { |
211 | if (redirection_undo_list) | |
212 | { | |
213 | dispose_redirects (redirection_undo_list); | |
214 | redirection_undo_list = (REDIRECT *)NULL; | |
215 | } | |
216 | if (exec_redirection_undo_list) | |
217 | dispose_exec_redirects (); | |
218 | } | |
219 | ||
220 | for (temp = list; temp; temp = temp->next) | |
221 | { | |
b80f6443 | 222 | error = do_redirection_internal (temp, flags); |
cce855bc JA |
223 | if (error) |
224 | { | |
225 | redirection_error (temp, error); | |
226 | return (error); | |
227 | } | |
228 | } | |
229 | return (0); | |
230 | } | |
231 | ||
232 | /* Return non-zero if the redirection pointed to by REDIRECT has a | |
233 | redirectee.filename that can be expanded. */ | |
234 | static int | |
235 | expandable_redirection_filename (redirect) | |
236 | REDIRECT *redirect; | |
237 | { | |
238 | switch (redirect->instruction) | |
239 | { | |
240 | case r_output_direction: | |
241 | case r_appending_to: | |
242 | case r_input_direction: | |
243 | case r_inputa_direction: | |
244 | case r_err_and_out: | |
3185942a | 245 | case r_append_err_and_out: |
cce855bc JA |
246 | case r_input_output: |
247 | case r_output_force: | |
248 | case r_duplicating_input_word: | |
249 | case r_duplicating_output_word: | |
7117c2d2 JA |
250 | case r_move_input_word: |
251 | case r_move_output_word: | |
cce855bc JA |
252 | return 1; |
253 | ||
254 | default: | |
255 | return 0; | |
256 | } | |
257 | } | |
258 | ||
259 | /* Expand the word in WORD returning a string. If WORD expands to | |
260 | multiple words (or no words), then return NULL. */ | |
261 | char * | |
262 | redirection_expand (word) | |
263 | WORD_DESC *word; | |
264 | { | |
265 | char *result; | |
266 | WORD_LIST *tlist1, *tlist2; | |
bb70624e JA |
267 | WORD_DESC *w; |
268 | ||
269 | w = copy_word (word); | |
270 | if (posixly_correct) | |
271 | w->flags |= W_NOSPLIT; | |
cce855bc | 272 | |
bb70624e | 273 | tlist1 = make_word_list (w, (WORD_LIST *)NULL); |
b80f6443 | 274 | expanding_redir = 1; |
cce855bc | 275 | tlist2 = expand_words_no_vars (tlist1); |
b80f6443 | 276 | expanding_redir = 0; |
cce855bc JA |
277 | dispose_words (tlist1); |
278 | ||
279 | if (!tlist2 || tlist2->next) | |
280 | { | |
281 | /* We expanded to no words, or to more than a single word. | |
282 | Dispose of the word list and return NULL. */ | |
283 | if (tlist2) | |
284 | dispose_words (tlist2); | |
285 | return ((char *)NULL); | |
286 | } | |
287 | result = string_list (tlist2); /* XXX savestring (tlist2->word->word)? */ | |
288 | dispose_words (tlist2); | |
289 | return (result); | |
290 | } | |
291 | ||
7117c2d2 JA |
292 | static int |
293 | write_here_string (fd, redirectee) | |
294 | int fd; | |
295 | WORD_DESC *redirectee; | |
296 | { | |
297 | char *herestr; | |
298 | int herelen, n, e; | |
299 | ||
0001803f | 300 | expanding_redir = 1; |
7117c2d2 | 301 | herestr = expand_string_to_string (redirectee->word, 0); |
0001803f | 302 | expanding_redir = 0; |
b80f6443 | 303 | herelen = STRLEN (herestr); |
7117c2d2 JA |
304 | |
305 | n = write (fd, herestr, herelen); | |
306 | if (n == herelen) | |
307 | { | |
308 | n = write (fd, "\n", 1); | |
309 | herelen = 1; | |
310 | } | |
311 | e = errno; | |
b80f6443 | 312 | FREE (herestr); |
7117c2d2 JA |
313 | if (n != herelen) |
314 | { | |
315 | if (e == 0) | |
316 | e = ENOSPC; | |
317 | return e; | |
318 | } | |
319 | return 0; | |
320 | } | |
321 | ||
cce855bc JA |
322 | /* Write the text of the here document pointed to by REDIRECTEE to the file |
323 | descriptor FD, which is already open to a temp file. Return 0 if the | |
324 | write is successful, otherwise return errno. */ | |
325 | static int | |
326 | write_here_document (fd, redirectee) | |
327 | int fd; | |
328 | WORD_DESC *redirectee; | |
329 | { | |
330 | char *document; | |
331 | int document_len, fd2; | |
332 | FILE *fp; | |
333 | register WORD_LIST *t, *tlist; | |
334 | ||
335 | /* Expand the text if the word that was specified had | |
336 | no quoting. The text that we expand is treated | |
337 | exactly as if it were surrounded by double quotes. */ | |
338 | ||
339 | if (redirectee->flags & W_QUOTED) | |
340 | { | |
341 | document = redirectee->word; | |
342 | document_len = strlen (document); | |
343 | /* Set errno to something reasonable if the write fails. */ | |
344 | if (write (fd, document, document_len) < document_len) | |
345 | { | |
346 | if (errno == 0) | |
347 | errno = ENOSPC; | |
348 | return (errno); | |
349 | } | |
350 | else | |
28ef6c31 | 351 | return 0; |
cce855bc JA |
352 | } |
353 | ||
0001803f | 354 | expanding_redir = 1; |
cce855bc | 355 | tlist = expand_string (redirectee->word, Q_HERE_DOCUMENT); |
0001803f CR |
356 | expanding_redir = 0; |
357 | ||
cce855bc JA |
358 | if (tlist) |
359 | { | |
360 | /* Try using buffered I/O (stdio) and writing a word | |
361 | at a time, letting stdio do the work of buffering | |
362 | for us rather than managing our own strings. Most | |
363 | stdios are not particularly fast, however -- this | |
364 | may need to be reconsidered later. */ | |
365 | if ((fd2 = dup (fd)) < 0 || (fp = fdopen (fd2, "w")) == NULL) | |
366 | { | |
367 | if (fd2 >= 0) | |
368 | close (fd2); | |
369 | return (errno); | |
370 | } | |
371 | errno = 0; | |
372 | for (t = tlist; t; t = t->next) | |
373 | { | |
374 | /* This is essentially the body of | |
375 | string_list_internal expanded inline. */ | |
376 | document = t->word->word; | |
377 | document_len = strlen (document); | |
378 | if (t != tlist) | |
379 | putc (' ', fp); /* separator */ | |
380 | fwrite (document, document_len, 1, fp); | |
381 | if (ferror (fp)) | |
382 | { | |
383 | if (errno == 0) | |
384 | errno = ENOSPC; | |
385 | fd2 = errno; | |
386 | fclose(fp); | |
387 | dispose_words (tlist); | |
388 | return (fd2); | |
389 | } | |
390 | } | |
cce855bc | 391 | dispose_words (tlist); |
f73dda09 JA |
392 | if (fclose (fp) != 0) |
393 | { | |
394 | if (errno == 0) | |
395 | errno = ENOSPC; | |
396 | return (errno); | |
397 | } | |
cce855bc JA |
398 | } |
399 | return 0; | |
400 | } | |
401 | ||
402 | /* Create a temporary file holding the text of the here document pointed to | |
403 | by REDIRECTEE, and return a file descriptor open for reading to the temp | |
404 | file. Return -1 on any error, and make sure errno is set appropriately. */ | |
405 | static int | |
7117c2d2 | 406 | here_document_to_fd (redirectee, ri) |
cce855bc | 407 | WORD_DESC *redirectee; |
7117c2d2 | 408 | enum r_instruction ri; |
cce855bc | 409 | { |
28ef6c31 | 410 | char *filename; |
bb70624e | 411 | int r, fd, fd2; |
cce855bc | 412 | |
3185942a | 413 | fd = sh_mktmpfd ("sh-thd", MT_USERANDOM|MT_USETMPDIR, &filename); |
cce855bc JA |
414 | |
415 | /* If we failed for some reason other than the file existing, abort */ | |
416 | if (fd < 0) | |
28ef6c31 JA |
417 | { |
418 | FREE (filename); | |
419 | return (fd); | |
420 | } | |
cce855bc JA |
421 | |
422 | errno = r = 0; /* XXX */ | |
423 | /* write_here_document returns 0 on success, errno on failure. */ | |
424 | if (redirectee->word) | |
7117c2d2 JA |
425 | r = (ri != r_reading_string) ? write_here_document (fd, redirectee) |
426 | : write_here_string (fd, redirectee); | |
cce855bc | 427 | |
cce855bc JA |
428 | if (r) |
429 | { | |
bb70624e | 430 | close (fd); |
cce855bc | 431 | unlink (filename); |
28ef6c31 | 432 | free (filename); |
cce855bc JA |
433 | errno = r; |
434 | return (-1); | |
435 | } | |
436 | ||
bb70624e JA |
437 | /* In an attempt to avoid races, we close the first fd only after opening |
438 | the second. */ | |
cce855bc | 439 | /* Make the document really temporary. Also make it the input. */ |
bb70624e | 440 | fd2 = open (filename, O_RDONLY, 0600); |
cce855bc | 441 | |
bb70624e | 442 | if (fd2 < 0) |
cce855bc JA |
443 | { |
444 | r = errno; | |
445 | unlink (filename); | |
28ef6c31 | 446 | free (filename); |
bb70624e | 447 | close (fd); |
cce855bc JA |
448 | errno = r; |
449 | return -1; | |
450 | } | |
451 | ||
bb70624e | 452 | close (fd); |
cce855bc JA |
453 | if (unlink (filename) < 0) |
454 | { | |
455 | r = errno; | |
28ef6c31 JA |
456 | #if defined (__CYGWIN__) |
457 | /* Under CygWin 1.1.0, the unlink will fail if the file is | |
458 | open. This hack will allow the previous action of silently | |
459 | ignoring the error, but will still leave the file there. This | |
460 | needs some kind of magic. */ | |
461 | if (r == EACCES) | |
462 | return (fd2); | |
463 | #endif /* __CYGWIN__ */ | |
bb70624e | 464 | close (fd2); |
28ef6c31 | 465 | free (filename); |
cce855bc JA |
466 | errno = r; |
467 | return (-1); | |
468 | } | |
469 | ||
28ef6c31 | 470 | free (filename); |
bb70624e | 471 | return (fd2); |
cce855bc JA |
472 | } |
473 | ||
bb70624e JA |
474 | #define RF_DEVFD 1 |
475 | #define RF_DEVSTDERR 2 | |
476 | #define RF_DEVSTDIN 3 | |
477 | #define RF_DEVSTDOUT 4 | |
478 | #define RF_DEVTCP 5 | |
479 | #define RF_DEVUDP 6 | |
480 | ||
481 | /* A list of pattern/value pairs for filenames that the redirection | |
482 | code handles specially. */ | |
483 | static STRING_INT_ALIST _redir_special_filenames[] = { | |
484 | #if !defined (HAVE_DEV_FD) | |
485 | { "/dev/fd/[0-9]*", RF_DEVFD }, | |
486 | #endif | |
487 | #if !defined (HAVE_DEV_STDIN) | |
488 | { "/dev/stderr", RF_DEVSTDERR }, | |
489 | { "/dev/stdin", RF_DEVSTDIN }, | |
490 | { "/dev/stdout", RF_DEVSTDOUT }, | |
491 | #endif | |
492 | #if defined (NETWORK_REDIRECTIONS) | |
493 | { "/dev/tcp/*/*", RF_DEVTCP }, | |
494 | { "/dev/udp/*/*", RF_DEVUDP }, | |
495 | #endif | |
496 | { (char *)NULL, -1 } | |
497 | }; | |
498 | ||
499 | static int | |
500 | redir_special_open (spec, filename, flags, mode, ri) | |
501 | int spec; | |
502 | char *filename; | |
503 | int flags, mode; | |
504 | enum r_instruction ri; | |
505 | { | |
506 | int fd; | |
f73dda09 | 507 | #if !defined (HAVE_DEV_FD) |
7117c2d2 | 508 | intmax_t lfd; |
f73dda09 | 509 | #endif |
bb70624e JA |
510 | |
511 | fd = -1; | |
512 | switch (spec) | |
513 | { | |
514 | #if !defined (HAVE_DEV_FD) | |
515 | case RF_DEVFD: | |
f73dda09 JA |
516 | if (all_digits (filename+8) && legal_number (filename+8, &lfd) && lfd == (int)lfd) |
517 | { | |
518 | fd = lfd; | |
3185942a | 519 | fd = fcntl (fd, F_DUPFD, SHELL_FD_BASE); |
f73dda09 | 520 | } |
bb70624e JA |
521 | else |
522 | fd = AMBIGUOUS_REDIRECT; | |
523 | break; | |
524 | #endif | |
525 | ||
526 | #if !defined (HAVE_DEV_STDIN) | |
527 | case RF_DEVSTDIN: | |
3185942a | 528 | fd = fcntl (0, F_DUPFD, SHELL_FD_BASE); |
bb70624e JA |
529 | break; |
530 | case RF_DEVSTDOUT: | |
3185942a | 531 | fd = fcntl (1, F_DUPFD, SHELL_FD_BASE); |
bb70624e JA |
532 | break; |
533 | case RF_DEVSTDERR: | |
3185942a | 534 | fd = fcntl (2, F_DUPFD, SHELL_FD_BASE); |
bb70624e JA |
535 | break; |
536 | #endif | |
537 | ||
538 | #if defined (NETWORK_REDIRECTIONS) | |
539 | case RF_DEVTCP: | |
540 | case RF_DEVUDP: | |
541 | #if defined (HAVE_NETWORK) | |
542 | fd = netopen (filename); | |
543 | #else | |
b80f6443 | 544 | internal_warning (_("/dev/(tcp|udp)/host/port not supported without networking")); |
bb70624e JA |
545 | fd = open (filename, flags, mode); |
546 | #endif | |
547 | break; | |
548 | #endif /* NETWORK_REDIRECTIONS */ | |
549 | } | |
550 | ||
551 | return fd; | |
552 | } | |
553 | ||
cce855bc JA |
554 | /* Open FILENAME with FLAGS in noclobber mode, hopefully avoiding most |
555 | race conditions and avoiding the problem where the file is replaced | |
556 | between the stat(2) and open(2). */ | |
557 | static int | |
bb70624e | 558 | noclobber_open (filename, flags, mode, ri) |
cce855bc | 559 | char *filename; |
bb70624e | 560 | int flags, mode; |
cce855bc JA |
561 | enum r_instruction ri; |
562 | { | |
563 | int r, fd; | |
564 | struct stat finfo, finfo2; | |
565 | ||
566 | /* If the file exists and is a regular file, return an error | |
567 | immediately. */ | |
568 | r = stat (filename, &finfo); | |
569 | if (r == 0 && (S_ISREG (finfo.st_mode))) | |
570 | return (NOCLOBBER_REDIRECT); | |
571 | ||
572 | /* If the file was not present (r != 0), make sure we open it | |
573 | exclusively so that if it is created before we open it, our open | |
574 | will fail. Make sure that we do not truncate an existing file. | |
575 | Note that we don't turn on O_EXCL unless the stat failed -- if | |
576 | the file was not a regular file, we leave O_EXCL off. */ | |
577 | flags &= ~O_TRUNC; | |
578 | if (r != 0) | |
579 | { | |
bb70624e | 580 | fd = open (filename, flags|O_EXCL, mode); |
cce855bc JA |
581 | return ((fd < 0 && errno == EEXIST) ? NOCLOBBER_REDIRECT : fd); |
582 | } | |
bb70624e | 583 | fd = open (filename, flags, mode); |
cce855bc JA |
584 | |
585 | /* If the open failed, return the file descriptor right away. */ | |
586 | if (fd < 0) | |
587 | return (errno == EEXIST ? NOCLOBBER_REDIRECT : fd); | |
588 | ||
589 | /* OK, the open succeeded, but the file may have been changed from a | |
590 | non-regular file to a regular file between the stat and the open. | |
591 | We are assuming that the O_EXCL open handles the case where FILENAME | |
592 | did not exist and is symlinked to an existing file between the stat | |
593 | and open. */ | |
594 | ||
595 | /* If we can open it and fstat the file descriptor, and neither check | |
596 | revealed that it was a regular file, and the file has not been replaced, | |
597 | return the file descriptor. */ | |
598 | if ((fstat (fd, &finfo2) == 0) && (S_ISREG (finfo2.st_mode) == 0) && | |
599 | r == 0 && (S_ISREG (finfo.st_mode) == 0) && | |
600 | same_file (filename, filename, &finfo, &finfo2)) | |
601 | return fd; | |
602 | ||
603 | /* The file has been replaced. badness. */ | |
604 | close (fd); | |
605 | errno = EEXIST; | |
606 | return (NOCLOBBER_REDIRECT); | |
607 | } | |
608 | ||
bb70624e JA |
609 | static int |
610 | redir_open (filename, flags, mode, ri) | |
611 | char *filename; | |
612 | int flags, mode; | |
613 | enum r_instruction ri; | |
614 | { | |
615 | int fd, r; | |
616 | ||
617 | r = find_string_in_alist (filename, _redir_special_filenames, 1); | |
618 | if (r >= 0) | |
619 | return (redir_special_open (r, filename, flags, mode, ri)); | |
620 | ||
621 | /* If we are in noclobber mode, you are not allowed to overwrite | |
622 | existing files. Check before opening. */ | |
28ef6c31 | 623 | if (noclobber && CLOBBERING_REDIRECT (ri)) |
bb70624e JA |
624 | { |
625 | fd = noclobber_open (filename, flags, mode, ri); | |
626 | if (fd == NOCLOBBER_REDIRECT) | |
627 | return (NOCLOBBER_REDIRECT); | |
628 | } | |
629 | else | |
630 | { | |
631 | fd = open (filename, flags, mode); | |
632 | #if defined (AFS) | |
633 | if ((fd < 0) && (errno == EACCES)) | |
95732b49 JA |
634 | { |
635 | fd = open (filename, flags & ~O_CREAT, mode); | |
636 | errno = EACCES; /* restore errno */ | |
637 | } | |
bb70624e JA |
638 | #endif /* AFS */ |
639 | } | |
640 | ||
641 | return fd; | |
642 | } | |
643 | ||
3185942a JA |
644 | static int |
645 | undoablefd (fd) | |
646 | int fd; | |
647 | { | |
648 | int clexec; | |
649 | ||
650 | clexec = fcntl (fd, F_GETFD, 0); | |
651 | if (clexec == -1 || (fd >= SHELL_FD_BASE && clexec == 1)) | |
652 | return 0; | |
653 | return 1; | |
654 | } | |
655 | ||
cce855bc JA |
656 | /* Do the specific redirection requested. Returns errno or one of the |
657 | special redirection errors (*_REDIRECT) in case of error, 0 on success. | |
b80f6443 JA |
658 | If flags & RX_ACTIVE is zero, then just do whatever is neccessary to |
659 | produce the appropriate side effects. flags & RX_UNDOABLE, if non-zero, | |
660 | says to remember how to undo each redirection. If flags & RX_CLEXEC is | |
661 | non-zero, then we set all file descriptors > 2 that we open to be | |
662 | close-on-exec. */ | |
cce855bc | 663 | static int |
b80f6443 | 664 | do_redirection_internal (redirect, flags) |
cce855bc | 665 | REDIRECT *redirect; |
b80f6443 | 666 | int flags; |
cce855bc JA |
667 | { |
668 | WORD_DESC *redirectee; | |
bb70624e | 669 | int redir_fd, fd, redirector, r, oflags; |
7117c2d2 | 670 | intmax_t lfd; |
cce855bc JA |
671 | char *redirectee_word; |
672 | enum r_instruction ri; | |
673 | REDIRECT *new_redirect; | |
0001803f | 674 | REDIRECTEE sd; |
cce855bc JA |
675 | |
676 | redirectee = redirect->redirectee.filename; | |
677 | redir_fd = redirect->redirectee.dest; | |
0001803f | 678 | redirector = redirect->redirector.dest; |
cce855bc JA |
679 | ri = redirect->instruction; |
680 | ||
0628567a JA |
681 | if (redirect->flags & RX_INTERNAL) |
682 | flags |= RX_INTERNAL; | |
95732b49 | 683 | |
7117c2d2 | 684 | if (TRANSLATE_REDIRECT (ri)) |
cce855bc | 685 | { |
0001803f CR |
686 | /* We have [N]>&WORD[-] or [N]<&WORD[-] (or {V}>&WORD[-] or {V}<&WORD-). |
687 | and WORD, then translate the redirection into a new one and | |
688 | continue. */ | |
cce855bc JA |
689 | redirectee_word = redirection_expand (redirectee); |
690 | ||
7117c2d2 JA |
691 | /* XXX - what to do with [N]<&$w- where w is unset or null? ksh93 |
692 | closes N. */ | |
cce855bc JA |
693 | if (redirectee_word == 0) |
694 | return (AMBIGUOUS_REDIRECT); | |
695 | else if (redirectee_word[0] == '-' && redirectee_word[1] == '\0') | |
696 | { | |
0001803f | 697 | sd = redirect->redirector; |
f73dda09 | 698 | rd.dest = 0; |
0001803f | 699 | new_redirect = make_redirection (sd, r_close_this, rd, 0); |
cce855bc JA |
700 | } |
701 | else if (all_digits (redirectee_word)) | |
702 | { | |
0001803f | 703 | sd = redirect->redirector; |
f73dda09 JA |
704 | if (legal_number (redirectee_word, &lfd) && (int)lfd == lfd) |
705 | rd.dest = lfd; | |
cce855bc | 706 | else |
f73dda09 | 707 | rd.dest = -1; /* XXX */ |
7117c2d2 JA |
708 | switch (ri) |
709 | { | |
710 | case r_duplicating_input_word: | |
0001803f | 711 | new_redirect = make_redirection (sd, r_duplicating_input, rd, 0); |
7117c2d2 JA |
712 | break; |
713 | case r_duplicating_output_word: | |
0001803f | 714 | new_redirect = make_redirection (sd, r_duplicating_output, rd, 0); |
7117c2d2 JA |
715 | break; |
716 | case r_move_input_word: | |
0001803f | 717 | new_redirect = make_redirection (sd, r_move_input, rd, 0); |
7117c2d2 JA |
718 | break; |
719 | case r_move_output_word: | |
0001803f | 720 | new_redirect = make_redirection (sd, r_move_output, rd, 0); |
7117c2d2 JA |
721 | break; |
722 | } | |
cce855bc | 723 | } |
0001803f | 724 | else if (ri == r_duplicating_output_word && (redirect->rflags & REDIR_VARASSIGN) == 0 && redirector == 1) |
cce855bc | 725 | { |
0001803f | 726 | sd = redirect->redirector; |
28ef6c31 | 727 | rd.filename = make_bare_word (redirectee_word); |
0001803f | 728 | new_redirect = make_redirection (sd, r_err_and_out, rd, 0); |
cce855bc JA |
729 | } |
730 | else | |
731 | { | |
732 | free (redirectee_word); | |
733 | return (AMBIGUOUS_REDIRECT); | |
734 | } | |
735 | ||
736 | free (redirectee_word); | |
737 | ||
738 | /* Set up the variables needed by the rest of the function from the | |
739 | new redirection. */ | |
740 | if (new_redirect->instruction == r_err_and_out) | |
741 | { | |
742 | char *alloca_hack; | |
743 | ||
744 | /* Copy the word without allocating any memory that must be | |
745 | explicitly freed. */ | |
746 | redirectee = (WORD_DESC *)alloca (sizeof (WORD_DESC)); | |
747 | xbcopy ((char *)new_redirect->redirectee.filename, | |
748 | (char *)redirectee, sizeof (WORD_DESC)); | |
749 | ||
750 | alloca_hack = (char *) | |
751 | alloca (1 + strlen (new_redirect->redirectee.filename->word)); | |
752 | redirectee->word = alloca_hack; | |
753 | strcpy (redirectee->word, new_redirect->redirectee.filename->word); | |
754 | } | |
755 | else | |
756 | /* It's guaranteed to be an integer, and shouldn't be freed. */ | |
757 | redirectee = new_redirect->redirectee.filename; | |
758 | ||
759 | redir_fd = new_redirect->redirectee.dest; | |
0001803f | 760 | redirector = new_redirect->redirector.dest; |
cce855bc JA |
761 | ri = new_redirect->instruction; |
762 | ||
763 | /* Overwrite the flags element of the old redirect with the new value. */ | |
764 | redirect->flags = new_redirect->flags; | |
765 | dispose_redirects (new_redirect); | |
766 | } | |
767 | ||
768 | switch (ri) | |
769 | { | |
770 | case r_output_direction: | |
771 | case r_appending_to: | |
772 | case r_input_direction: | |
773 | case r_inputa_direction: | |
774 | case r_err_and_out: /* command &>filename */ | |
3185942a | 775 | case r_append_err_and_out: /* command &>> filename */ |
cce855bc JA |
776 | case r_input_output: |
777 | case r_output_force: | |
bb70624e | 778 | if (posixly_correct && interactive_shell == 0) |
28ef6c31 JA |
779 | { |
780 | oflags = redirectee->flags; | |
781 | redirectee->flags |= W_NOGLOB; | |
782 | } | |
cce855bc | 783 | redirectee_word = redirection_expand (redirectee); |
bb70624e JA |
784 | if (posixly_correct && interactive_shell == 0) |
785 | redirectee->flags = oflags; | |
cce855bc JA |
786 | |
787 | if (redirectee_word == 0) | |
788 | return (AMBIGUOUS_REDIRECT); | |
789 | ||
790 | #if defined (RESTRICTED_SHELL) | |
791 | if (restricted && (WRITE_REDIRECT (ri))) | |
792 | { | |
793 | free (redirectee_word); | |
794 | return (RESTRICTED_REDIRECT); | |
795 | } | |
796 | #endif /* RESTRICTED_SHELL */ | |
797 | ||
bb70624e | 798 | fd = redir_open (redirectee_word, redirect->flags, 0666, ri); |
cce855bc JA |
799 | free (redirectee_word); |
800 | ||
bb70624e | 801 | if (fd == NOCLOBBER_REDIRECT) |
28ef6c31 | 802 | return (fd); |
bb70624e | 803 | |
cce855bc JA |
804 | if (fd < 0) |
805 | return (errno); | |
806 | ||
b80f6443 | 807 | if (flags & RX_ACTIVE) |
cce855bc | 808 | { |
0001803f CR |
809 | if (redirect->rflags & REDIR_VARASSIGN) |
810 | redirector = fcntl (fd, F_DUPFD, SHELL_FD_BASE); /* XXX try this for now */ | |
811 | ||
b80f6443 | 812 | if (flags & RX_UNDOABLE) |
f73dda09 JA |
813 | { |
814 | /* Only setup to undo it if the thing to undo is active. */ | |
815 | if ((fd != redirector) && (fcntl (redirector, F_GETFD, 0) != -1)) | |
3185942a | 816 | add_undo_redirect (redirector, ri, -1); |
f73dda09 JA |
817 | else |
818 | add_undo_close_redirect (redirector); | |
819 | } | |
cce855bc JA |
820 | |
821 | #if defined (BUFFERED_INPUT) | |
822 | check_bash_input (redirector); | |
823 | #endif | |
824 | ||
3185942a JA |
825 | /* Make sure there is no pending output before we change the state |
826 | of the underlying file descriptor, since the builtins use stdio | |
827 | for output. */ | |
828 | if (redirector == 1 && fileno (stdout) == redirector) | |
829 | { | |
830 | fflush (stdout); | |
831 | fpurge (stdout); | |
832 | } | |
833 | else if (redirector == 2 && fileno (stderr) == redirector) | |
834 | { | |
835 | fflush (stderr); | |
836 | fpurge (stderr); | |
837 | } | |
838 | ||
0001803f CR |
839 | if (redirect->rflags & REDIR_VARASSIGN) |
840 | { | |
841 | if ((r = redir_varassign (redirect, redirector)) < 0) | |
842 | { | |
843 | close (redirector); | |
844 | close (fd); | |
845 | return (r); /* XXX */ | |
846 | } | |
847 | } | |
848 | else if ((fd != redirector) && (dup2 (fd, redirector) < 0)) | |
cce855bc JA |
849 | return (errno); |
850 | ||
851 | #if defined (BUFFERED_INPUT) | |
852 | /* Do not change the buffered stream for an implicit redirection | |
853 | of /dev/null to fd 0 for asynchronous commands without job | |
854 | control (r_inputa_direction). */ | |
855 | if (ri == r_input_direction || ri == r_input_output) | |
856 | duplicate_buffered_stream (fd, redirector); | |
857 | #endif /* BUFFERED_INPUT */ | |
858 | ||
859 | /* | |
860 | * If we're remembering, then this is the result of a while, for | |
861 | * or until loop with a loop redirection, or a function/builtin | |
862 | * executing in the parent shell with a redirection. In the | |
863 | * function/builtin case, we want to set all file descriptors > 2 | |
864 | * to be close-on-exec to duplicate the effect of the old | |
865 | * for i = 3 to NOFILE close(i) loop. In the case of the loops, | |
866 | * both sh and ksh leave the file descriptors open across execs. | |
867 | * The Posix standard mentions only the exec builtin. | |
868 | */ | |
b80f6443 | 869 | if ((flags & RX_CLEXEC) && (redirector > 2)) |
cce855bc JA |
870 | SET_CLOSE_ON_EXEC (redirector); |
871 | } | |
872 | ||
873 | if (fd != redirector) | |
874 | { | |
875 | #if defined (BUFFERED_INPUT) | |
876 | if (INPUT_REDIRECT (ri)) | |
877 | close_buffered_fd (fd); | |
878 | else | |
879 | #endif /* !BUFFERED_INPUT */ | |
880 | close (fd); /* Don't close what we just opened! */ | |
881 | } | |
882 | ||
883 | /* If we are hacking both stdout and stderr, do the stderr | |
0001803f | 884 | redirection here. XXX - handle {var} here? */ |
3185942a | 885 | if (ri == r_err_and_out || ri == r_append_err_and_out) |
cce855bc | 886 | { |
b80f6443 | 887 | if (flags & RX_ACTIVE) |
cce855bc | 888 | { |
b80f6443 | 889 | if (flags & RX_UNDOABLE) |
3185942a | 890 | add_undo_redirect (2, ri, -1); |
cce855bc JA |
891 | if (dup2 (1, 2) < 0) |
892 | return (errno); | |
893 | } | |
894 | } | |
895 | break; | |
896 | ||
897 | case r_reading_until: | |
898 | case r_deblank_reading_until: | |
7117c2d2 | 899 | case r_reading_string: |
cce855bc JA |
900 | /* REDIRECTEE is a pointer to a WORD_DESC containing the text of |
901 | the new input. Place it in a temporary file. */ | |
902 | if (redirectee) | |
903 | { | |
7117c2d2 | 904 | fd = here_document_to_fd (redirectee, ri); |
cce855bc JA |
905 | |
906 | if (fd < 0) | |
907 | { | |
908 | heredoc_errno = errno; | |
909 | return (HEREDOC_REDIRECT); | |
910 | } | |
911 | ||
0001803f CR |
912 | if (redirect->rflags & REDIR_VARASSIGN) |
913 | redirector = fcntl (fd, F_DUPFD, SHELL_FD_BASE); /* XXX try this for now */ | |
914 | ||
b80f6443 | 915 | if (flags & RX_ACTIVE) |
cce855bc | 916 | { |
b80f6443 | 917 | if (flags & RX_UNDOABLE) |
f73dda09 JA |
918 | { |
919 | /* Only setup to undo it if the thing to undo is active. */ | |
920 | if ((fd != redirector) && (fcntl (redirector, F_GETFD, 0) != -1)) | |
3185942a | 921 | add_undo_redirect (redirector, ri, -1); |
f73dda09 JA |
922 | else |
923 | add_undo_close_redirect (redirector); | |
924 | } | |
cce855bc JA |
925 | |
926 | #if defined (BUFFERED_INPUT) | |
927 | check_bash_input (redirector); | |
928 | #endif | |
0001803f CR |
929 | if (redirect->rflags & REDIR_VARASSIGN) |
930 | { | |
931 | if ((r = redir_varassign (redirect, redirector)) < 0) | |
932 | { | |
933 | close (redirector); | |
934 | close (fd); | |
935 | return (r); /* XXX */ | |
936 | } | |
937 | } | |
938 | else if (fd != redirector && dup2 (fd, redirector) < 0) | |
cce855bc JA |
939 | { |
940 | r = errno; | |
941 | close (fd); | |
942 | return (r); | |
943 | } | |
944 | ||
945 | #if defined (BUFFERED_INPUT) | |
946 | duplicate_buffered_stream (fd, redirector); | |
947 | #endif | |
948 | ||
b80f6443 | 949 | if ((flags & RX_CLEXEC) && (redirector > 2)) |
cce855bc JA |
950 | SET_CLOSE_ON_EXEC (redirector); |
951 | } | |
952 | ||
bb70624e | 953 | if (fd != redirector) |
cce855bc | 954 | #if defined (BUFFERED_INPUT) |
bb70624e | 955 | close_buffered_fd (fd); |
cce855bc | 956 | #else |
bb70624e | 957 | close (fd); |
cce855bc JA |
958 | #endif |
959 | } | |
960 | break; | |
961 | ||
962 | case r_duplicating_input: | |
963 | case r_duplicating_output: | |
7117c2d2 JA |
964 | case r_move_input: |
965 | case r_move_output: | |
0001803f CR |
966 | if ((flags & RX_ACTIVE) && (redirect->rflags & REDIR_VARASSIGN)) |
967 | redirector = fcntl (redir_fd, F_DUPFD, SHELL_FD_BASE); /* XXX try this for now */ | |
968 | ||
b80f6443 | 969 | if ((flags & RX_ACTIVE) && (redir_fd != redirector)) |
cce855bc | 970 | { |
b80f6443 | 971 | if (flags & RX_UNDOABLE) |
f73dda09 JA |
972 | { |
973 | /* Only setup to undo it if the thing to undo is active. */ | |
974 | if (fcntl (redirector, F_GETFD, 0) != -1) | |
3185942a | 975 | add_undo_redirect (redirector, ri, redir_fd); |
f73dda09 JA |
976 | else |
977 | add_undo_close_redirect (redirector); | |
978 | } | |
cce855bc JA |
979 | #if defined (BUFFERED_INPUT) |
980 | check_bash_input (redirector); | |
981 | #endif | |
0001803f CR |
982 | if (redirect->rflags & REDIR_VARASSIGN) |
983 | { | |
984 | if ((r = redir_varassign (redirect, redirector)) < 0) | |
985 | { | |
986 | close (redirector); | |
987 | return (r); /* XXX */ | |
988 | } | |
989 | } | |
cce855bc | 990 | /* This is correct. 2>&1 means dup2 (1, 2); */ |
0001803f | 991 | else if (dup2 (redir_fd, redirector) < 0) |
cce855bc JA |
992 | return (errno); |
993 | ||
994 | #if defined (BUFFERED_INPUT) | |
7117c2d2 | 995 | if (ri == r_duplicating_input || ri == r_move_input) |
cce855bc JA |
996 | duplicate_buffered_stream (redir_fd, redirector); |
997 | #endif /* BUFFERED_INPUT */ | |
998 | ||
999 | /* First duplicate the close-on-exec state of redirectee. dup2 | |
1000 | leaves the flag unset on the new descriptor, which means it | |
1001 | stays open. Only set the close-on-exec bit for file descriptors | |
1002 | greater than 2 in any case, since 0-2 should always be open | |
95732b49 JA |
1003 | unless closed by something like `exec 2<&-'. It should always |
1004 | be safe to set fds > 2 to close-on-exec if they're being used to | |
1005 | save file descriptors < 2, since we don't need to preserve the | |
1006 | state of the close-on-exec flag for those fds -- they should | |
1007 | always be open. */ | |
cce855bc JA |
1008 | /* if ((already_set || set_unconditionally) && (ok_to_set)) |
1009 | set_it () */ | |
95732b49 JA |
1010 | #if 0 |
1011 | if (((fcntl (redir_fd, F_GETFD, 0) == 1) || redir_fd < 2 || (flags & RX_CLEXEC)) && | |
1012 | (redirector > 2)) | |
1013 | #else | |
1014 | if (((fcntl (redir_fd, F_GETFD, 0) == 1) || (redir_fd < 2 && (flags & RX_INTERNAL)) || (flags & RX_CLEXEC)) && | |
cce855bc | 1015 | (redirector > 2)) |
95732b49 | 1016 | #endif |
cce855bc | 1017 | SET_CLOSE_ON_EXEC (redirector); |
7117c2d2 | 1018 | |
3185942a JA |
1019 | /* When undoing saving of non-standard file descriptors (>=3) using |
1020 | file descriptors >= SHELL_FD_BASE, we set the saving fd to be | |
1021 | close-on-exec and use a flag to decide how to set close-on-exec | |
1022 | when the fd is restored. */ | |
1023 | if ((redirect->flags & RX_INTERNAL) && (redirect->flags & RX_SAVCLEXEC) && redirector >= 3 && redir_fd >= SHELL_FD_BASE) | |
1024 | SET_OPEN_ON_EXEC (redirector); | |
1025 | ||
7117c2d2 JA |
1026 | /* dup-and-close redirection */ |
1027 | if (ri == r_move_input || ri == r_move_output) | |
3185942a | 1028 | { |
0001803f CR |
1029 | xtrace_fdchk (redir_fd); |
1030 | ||
3185942a JA |
1031 | close (redir_fd); |
1032 | #if defined (COPROCESS_SUPPORT) | |
1033 | coproc_fdchk (redir_fd); /* XXX - loses coproc fds */ | |
1034 | #endif | |
1035 | } | |
cce855bc JA |
1036 | } |
1037 | break; | |
1038 | ||
1039 | case r_close_this: | |
b80f6443 | 1040 | if (flags & RX_ACTIVE) |
cce855bc | 1041 | { |
0001803f CR |
1042 | if (redirect->rflags & REDIR_VARASSIGN) |
1043 | { | |
1044 | redirector = redir_varvalue (redirect); | |
1045 | if (redirector < 0) | |
1046 | return AMBIGUOUS_REDIRECT; | |
1047 | } | |
1048 | ||
b80f6443 | 1049 | if ((flags & RX_UNDOABLE) && (fcntl (redirector, F_GETFD, 0) != -1)) |
3185942a JA |
1050 | add_undo_redirect (redirector, ri, -1); |
1051 | ||
1052 | #if defined (COPROCESS_SUPPORT) | |
1053 | coproc_fdchk (redirector); | |
1054 | #endif | |
0001803f | 1055 | xtrace_fdchk (redirector); |
cce855bc JA |
1056 | |
1057 | #if defined (BUFFERED_INPUT) | |
1058 | check_bash_input (redirector); | |
1059 | close_buffered_fd (redirector); | |
1060 | #else /* !BUFFERED_INPUT */ | |
1061 | close (redirector); | |
1062 | #endif /* !BUFFERED_INPUT */ | |
1063 | } | |
1064 | break; | |
1065 | ||
1066 | case r_duplicating_input_word: | |
1067 | case r_duplicating_output_word: | |
1068 | break; | |
1069 | } | |
1070 | return (0); | |
1071 | } | |
1072 | ||
cce855bc JA |
1073 | /* Remember the file descriptor associated with the slot FD, |
1074 | on REDIRECTION_UNDO_LIST. Note that the list will be reversed | |
1075 | before it is executed. Any redirections that need to be undone | |
1076 | even if REDIRECTION_UNDO_LIST is discarded by the exec builtin | |
3185942a JA |
1077 | are also saved on EXEC_REDIRECTION_UNDO_LIST. FDBASE says where to |
1078 | start the duplicating. If it's less than SHELL_FD_BASE, we're ok, | |
1079 | and can use SHELL_FD_BASE (-1 == don't care). If it's >= SHELL_FD_BASE, | |
1080 | we have to make sure we don't use fdbase to save a file descriptor, | |
1081 | since we're going to use it later (e.g., make sure we don't save fd 0 | |
1082 | to fd 10 if we have a redirection like 0<&10). If the value of fdbase | |
1083 | puts the process over its fd limit, causing fcntl to fail, we try | |
1084 | again with SHELL_FD_BASE. */ | |
cce855bc | 1085 | static int |
3185942a | 1086 | add_undo_redirect (fd, ri, fdbase) |
cce855bc | 1087 | int fd; |
0628567a | 1088 | enum r_instruction ri; |
3185942a | 1089 | int fdbase; |
cce855bc JA |
1090 | { |
1091 | int new_fd, clexec_flag; | |
1092 | REDIRECT *new_redirect, *closer, *dummy_redirect; | |
0001803f | 1093 | REDIRECTEE sd; |
cce855bc | 1094 | |
3185942a JA |
1095 | new_fd = fcntl (fd, F_DUPFD, (fdbase < SHELL_FD_BASE) ? SHELL_FD_BASE : fdbase+1); |
1096 | if (new_fd < 0) | |
1097 | new_fd = fcntl (fd, F_DUPFD, SHELL_FD_BASE); | |
cce855bc JA |
1098 | |
1099 | if (new_fd < 0) | |
1100 | { | |
b80f6443 | 1101 | sys_error (_("redirection error: cannot duplicate fd")); |
cce855bc JA |
1102 | return (-1); |
1103 | } | |
1104 | ||
1105 | clexec_flag = fcntl (fd, F_GETFD, 0); | |
1106 | ||
0001803f | 1107 | sd.dest = new_fd; |
f73dda09 | 1108 | rd.dest = 0; |
0001803f | 1109 | closer = make_redirection (sd, r_close_this, rd, 0); |
95732b49 | 1110 | closer->flags |= RX_INTERNAL; |
cce855bc JA |
1111 | dummy_redirect = copy_redirects (closer); |
1112 | ||
0001803f | 1113 | sd.dest = fd; |
f73dda09 | 1114 | rd.dest = new_fd; |
28ef6c31 | 1115 | if (fd == 0) |
0001803f | 1116 | new_redirect = make_redirection (sd, r_duplicating_input, rd, 0); |
28ef6c31 | 1117 | else |
0001803f | 1118 | new_redirect = make_redirection (sd, r_duplicating_output, rd, 0); |
95732b49 | 1119 | new_redirect->flags |= RX_INTERNAL; |
3185942a JA |
1120 | if (clexec_flag == 0 && fd >= 3 && new_fd >= SHELL_FD_BASE) |
1121 | new_redirect->flags |= RX_SAVCLEXEC; | |
cce855bc JA |
1122 | new_redirect->next = closer; |
1123 | ||
1124 | closer->next = redirection_undo_list; | |
1125 | redirection_undo_list = new_redirect; | |
1126 | ||
1127 | /* Save redirections that need to be undone even if the undo list | |
1128 | is thrown away by the `exec' builtin. */ | |
1129 | add_exec_redirect (dummy_redirect); | |
1130 | ||
95732b49 JA |
1131 | /* experimental: if we're saving a redirection to undo for a file descriptor |
1132 | above SHELL_FD_BASE, add a redirection to be undone if the exec builtin | |
3185942a JA |
1133 | causes redirections to be discarded. There needs to be a difference |
1134 | between fds that are used to save other fds and then are the target of | |
1135 | user redirctions and fds that are just the target of user redirections. | |
1136 | We use the close-on-exec flag to tell the difference; fds > SHELL_FD_BASE | |
1137 | that have the close-on-exec flag set are assumed to be fds used internally | |
1138 | to save others. */ | |
1139 | if (fd >= SHELL_FD_BASE && ri != r_close_this && clexec_flag) | |
95732b49 | 1140 | { |
0001803f | 1141 | sd.dest = fd; |
95732b49 | 1142 | rd.dest = new_fd; |
0001803f | 1143 | new_redirect = make_redirection (sd, r_duplicating_output, rd, 0); |
3185942a JA |
1144 | new_redirect->flags |= RX_INTERNAL; |
1145 | ||
95732b49 | 1146 | add_exec_redirect (new_redirect); |
95732b49 JA |
1147 | } |
1148 | ||
cce855bc JA |
1149 | /* File descriptors used only for saving others should always be |
1150 | marked close-on-exec. Unfortunately, we have to preserve the | |
1151 | close-on-exec state of the file descriptor we are saving, since | |
1152 | fcntl (F_DUPFD) sets the new file descriptor to remain open | |
1153 | across execs. If, however, the file descriptor whose state we | |
1154 | are saving is <= 2, we can just set the close-on-exec flag, | |
1155 | because file descriptors 0-2 should always be open-on-exec, | |
1156 | and the restore above in do_redirection() will take care of it. */ | |
1157 | if (clexec_flag || fd < 3) | |
1158 | SET_CLOSE_ON_EXEC (new_fd); | |
3185942a JA |
1159 | else if (redirection_undo_list->flags & RX_SAVCLEXEC) |
1160 | SET_CLOSE_ON_EXEC (new_fd); | |
cce855bc JA |
1161 | |
1162 | return (0); | |
1163 | } | |
1164 | ||
1165 | /* Set up to close FD when we are finished with the current command | |
1166 | and its redirections. */ | |
1167 | static void | |
1168 | add_undo_close_redirect (fd) | |
1169 | int fd; | |
1170 | { | |
1171 | REDIRECT *closer; | |
0001803f | 1172 | REDIRECTEE sd; |
cce855bc | 1173 | |
0001803f | 1174 | sd.dest = fd; |
f73dda09 | 1175 | rd.dest = 0; |
0001803f | 1176 | closer = make_redirection (sd, r_close_this, rd, 0); |
95732b49 | 1177 | closer->flags |= RX_INTERNAL; |
cce855bc JA |
1178 | closer->next = redirection_undo_list; |
1179 | redirection_undo_list = closer; | |
1180 | } | |
1181 | ||
1182 | static void | |
1183 | add_exec_redirect (dummy_redirect) | |
1184 | REDIRECT *dummy_redirect; | |
1185 | { | |
1186 | dummy_redirect->next = exec_redirection_undo_list; | |
1187 | exec_redirection_undo_list = dummy_redirect; | |
1188 | } | |
1189 | ||
bb70624e JA |
1190 | /* Return 1 if the redirection specified by RI and REDIRECTOR alters the |
1191 | standard input. */ | |
1192 | static int | |
1193 | stdin_redirection (ri, redirector) | |
1194 | enum r_instruction ri; | |
1195 | int redirector; | |
1196 | { | |
1197 | switch (ri) | |
1198 | { | |
1199 | case r_input_direction: | |
1200 | case r_inputa_direction: | |
1201 | case r_input_output: | |
1202 | case r_reading_until: | |
1203 | case r_deblank_reading_until: | |
7117c2d2 | 1204 | case r_reading_string: |
bb70624e JA |
1205 | return (1); |
1206 | case r_duplicating_input: | |
1207 | case r_duplicating_input_word: | |
1208 | case r_close_this: | |
1209 | return (redirector == 0); | |
1210 | case r_output_direction: | |
1211 | case r_appending_to: | |
1212 | case r_duplicating_output: | |
1213 | case r_err_and_out: | |
3185942a | 1214 | case r_append_err_and_out: |
bb70624e JA |
1215 | case r_output_force: |
1216 | case r_duplicating_output_word: | |
1217 | return (0); | |
1218 | } | |
1219 | return (0); | |
1220 | } | |
1221 | ||
cce855bc JA |
1222 | /* Return non-zero if any of the redirections in REDIRS alter the standard |
1223 | input. */ | |
1224 | int | |
1225 | stdin_redirects (redirs) | |
1226 | REDIRECT *redirs; | |
1227 | { | |
1228 | REDIRECT *rp; | |
1229 | int n; | |
1230 | ||
1231 | for (n = 0, rp = redirs; rp; rp = rp->next) | |
0001803f CR |
1232 | if ((rp->rflags & REDIR_VARASSIGN) == 0) |
1233 | n += stdin_redirection (rp->instruction, rp->redirector.dest); | |
cce855bc JA |
1234 | return n; |
1235 | } | |
0001803f CR |
1236 | |
1237 | /* These don't yet handle array references */ | |
1238 | static int | |
1239 | redir_varassign (redir, fd) | |
1240 | REDIRECT *redir; | |
1241 | int fd; | |
1242 | { | |
1243 | WORD_DESC *w; | |
1244 | SHELL_VAR *v; | |
1245 | ||
1246 | w = redir->redirector.filename; | |
1247 | v = bind_var_to_int (w->word, fd); | |
1248 | if (v == 0 || readonly_p (v) || noassign_p (v)) | |
1249 | return BADVAR_REDIRECT; | |
1250 | ||
1251 | return 0; | |
1252 | } | |
1253 | ||
1254 | static int | |
1255 | redir_varvalue (redir) | |
1256 | REDIRECT *redir; | |
1257 | { | |
1258 | SHELL_VAR *v; | |
1259 | char *val; | |
1260 | intmax_t vmax; | |
1261 | int i; | |
1262 | ||
1263 | /* XXX - handle set -u here? */ | |
1264 | v = find_variable (redir->redirector.filename->word); | |
1265 | if (v == 0 || invisible_p (v)) | |
1266 | return -1; | |
1267 | ||
1268 | val = get_variable_value (v); | |
1269 | if (val == 0 || *val == 0) | |
1270 | return -1; | |
1271 | ||
1272 | if (legal_number (val, &vmax) < 0) | |
1273 | return -1; | |
1274 | ||
1275 | i = vmax; /* integer truncation */ | |
1276 | return i; | |
1277 | } |