Commit | Line | Data |
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5a17353c DD |
1 | /* Utilities to execute a program in a subprocess (possibly linked by pipes |
2 | with other subprocesses), and wait for it. Generic Unix version | |
3 | (also used for UWIN and VMS). | |
533da483 | 4 | Copyright (C) 1996-2020 Free Software Foundation, Inc. |
5a17353c DD |
5 | |
6 | This file is part of the libiberty library. | |
7 | Libiberty is free software; you can redistribute it and/or | |
8 | modify it under the terms of the GNU Library General Public | |
9 | License as published by the Free Software Foundation; either | |
10 | version 2 of the License, or (at your option) any later version. | |
11 | ||
12 | Libiberty 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 GNU | |
15 | Library General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU Library General Public | |
18 | License along with libiberty; see the file COPYING.LIB. If not, | |
979c05d3 NC |
19 | write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, |
20 | Boston, MA 02110-1301, USA. */ | |
5a17353c | 21 | |
b109e79a ILT |
22 | #include "config.h" |
23 | #include "libiberty.h" | |
5a17353c | 24 | #include "pex-common.h" |
35a88fa5 | 25 | #include "environ.h" |
5a17353c DD |
26 | |
27 | #include <stdio.h> | |
b109e79a | 28 | #include <signal.h> |
5a17353c DD |
29 | #include <errno.h> |
30 | #ifdef NEED_DECLARATION_ERRNO | |
31 | extern int errno; | |
32 | #endif | |
b109e79a ILT |
33 | #ifdef HAVE_STDLIB_H |
34 | #include <stdlib.h> | |
35 | #endif | |
5a17353c DD |
36 | #ifdef HAVE_STRING_H |
37 | #include <string.h> | |
38 | #endif | |
39 | #ifdef HAVE_UNISTD_H | |
40 | #include <unistd.h> | |
41 | #endif | |
b109e79a ILT |
42 | |
43 | #include <sys/types.h> | |
44 | ||
45 | #ifdef HAVE_FCNTL_H | |
46 | #include <fcntl.h> | |
5a17353c DD |
47 | #endif |
48 | #ifdef HAVE_SYS_WAIT_H | |
49 | #include <sys/wait.h> | |
50 | #endif | |
b109e79a ILT |
51 | #ifdef HAVE_GETRUSAGE |
52 | #include <sys/time.h> | |
53 | #include <sys/resource.h> | |
54 | #endif | |
55 | #ifdef HAVE_SYS_STAT_H | |
56 | #include <sys/stat.h> | |
5a17353c | 57 | #endif |
9c55e064 RH |
58 | #ifdef HAVE_PROCESS_H |
59 | #include <process.h> | |
60 | #endif | |
b109e79a | 61 | |
12a7367e DD |
62 | #ifdef vfork /* Autoconf may define this to fork for us. */ |
63 | # define VFORK_STRING "fork" | |
64 | #else | |
65 | # define VFORK_STRING "vfork" | |
66 | #endif | |
67 | #ifdef HAVE_VFORK_H | |
68 | #include <vfork.h> | |
69 | #endif | |
9fef968a DD |
70 | #if defined(VMS) && defined (__LONG_POINTERS) |
71 | #ifndef __CHAR_PTR32 | |
72 | typedef char * __char_ptr32 | |
73 | __attribute__ ((mode (SI))); | |
74 | #endif | |
75 | ||
76 | typedef __char_ptr32 *__char_ptr_char_ptr32 | |
77 | __attribute__ ((mode (SI))); | |
78 | ||
79 | /* Return a 32 bit pointer to an array of 32 bit pointers | |
80 | given a 64 bit pointer to an array of 64 bit pointers. */ | |
81 | ||
82 | static __char_ptr_char_ptr32 | |
83 | to_ptr32 (char **ptr64) | |
84 | { | |
85 | int argc; | |
86 | __char_ptr_char_ptr32 short_argv; | |
87 | ||
b3641a6e DD |
88 | /* Count number of arguments. */ |
89 | for (argc = 0; ptr64[argc] != NULL; argc++) | |
90 | ; | |
12a7367e | 91 | |
9fef968a DD |
92 | /* Reallocate argv with 32 bit pointers. */ |
93 | short_argv = (__char_ptr_char_ptr32) decc$malloc | |
94 | (sizeof (__char_ptr32) * (argc + 1)); | |
95 | ||
b3641a6e | 96 | for (argc = 0; ptr64[argc] != NULL; argc++) |
9fef968a DD |
97 | short_argv[argc] = (__char_ptr32) decc$strdup (ptr64[argc]); |
98 | ||
99 | short_argv[argc] = (__char_ptr32) 0; | |
100 | return short_argv; | |
101 | ||
102 | } | |
103 | #else | |
104 | #define to_ptr32(argv) argv | |
105 | #endif | |
5a17353c | 106 | |
b109e79a ILT |
107 | /* File mode to use for private and world-readable files. */ |
108 | ||
109 | #if defined (S_IRUSR) && defined (S_IWUSR) && defined (S_IRGRP) && defined (S_IWGRP) && defined (S_IROTH) && defined (S_IWOTH) | |
110 | #define PUBLIC_MODE \ | |
111 | (S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH) | |
112 | #else | |
113 | #define PUBLIC_MODE 0666 | |
114 | #endif | |
115 | ||
116 | /* Get the exit status of a particular process, and optionally get the | |
117 | time that it took. This is simple if we have wait4, slightly | |
118 | harder if we have waitpid, and is a pain if we only have wait. */ | |
119 | ||
120 | static pid_t pex_wait (struct pex_obj *, pid_t, int *, struct pex_time *); | |
121 | ||
122 | #ifdef HAVE_WAIT4 | |
123 | ||
124 | static pid_t | |
125 | pex_wait (struct pex_obj *obj ATTRIBUTE_UNUSED, pid_t pid, int *status, | |
126 | struct pex_time *time) | |
127 | { | |
128 | pid_t ret; | |
129 | struct rusage r; | |
130 | ||
131 | #ifdef HAVE_WAITPID | |
132 | if (time == NULL) | |
133 | return waitpid (pid, status, 0); | |
134 | #endif | |
135 | ||
136 | ret = wait4 (pid, status, 0, &r); | |
137 | ||
138 | if (time != NULL) | |
139 | { | |
140 | time->user_seconds = r.ru_utime.tv_sec; | |
141 | time->user_microseconds= r.ru_utime.tv_usec; | |
142 | time->system_seconds = r.ru_stime.tv_sec; | |
143 | time->system_microseconds= r.ru_stime.tv_usec; | |
144 | } | |
145 | ||
146 | return ret; | |
147 | } | |
148 | ||
149 | #else /* ! defined (HAVE_WAIT4) */ | |
150 | ||
151 | #ifdef HAVE_WAITPID | |
152 | ||
153 | #ifndef HAVE_GETRUSAGE | |
154 | ||
155 | static pid_t | |
156 | pex_wait (struct pex_obj *obj ATTRIBUTE_UNUSED, pid_t pid, int *status, | |
157 | struct pex_time *time) | |
158 | { | |
159 | if (time != NULL) | |
160 | memset (time, 0, sizeof (struct pex_time)); | |
161 | return waitpid (pid, status, 0); | |
162 | } | |
163 | ||
164 | #else /* defined (HAVE_GETRUSAGE) */ | |
165 | ||
166 | static pid_t | |
167 | pex_wait (struct pex_obj *obj ATTRIBUTE_UNUSED, pid_t pid, int *status, | |
168 | struct pex_time *time) | |
169 | { | |
170 | struct rusage r1, r2; | |
171 | pid_t ret; | |
172 | ||
173 | if (time == NULL) | |
174 | return waitpid (pid, status, 0); | |
175 | ||
176 | getrusage (RUSAGE_CHILDREN, &r1); | |
177 | ||
178 | ret = waitpid (pid, status, 0); | |
179 | if (ret < 0) | |
180 | return ret; | |
181 | ||
182 | getrusage (RUSAGE_CHILDREN, &r2); | |
183 | ||
184 | time->user_seconds = r2.ru_utime.tv_sec - r1.ru_utime.tv_sec; | |
185 | time->user_microseconds = r2.ru_utime.tv_usec - r1.ru_utime.tv_usec; | |
186 | if (r2.ru_utime.tv_usec < r1.ru_utime.tv_usec) | |
187 | { | |
188 | --time->user_seconds; | |
189 | time->user_microseconds += 1000000; | |
190 | } | |
191 | ||
192 | time->system_seconds = r2.ru_stime.tv_sec - r1.ru_stime.tv_sec; | |
193 | time->system_microseconds = r2.ru_stime.tv_usec - r1.ru_stime.tv_usec; | |
194 | if (r2.ru_stime.tv_usec < r1.ru_stime.tv_usec) | |
195 | { | |
196 | --time->system_seconds; | |
197 | time->system_microseconds += 1000000; | |
198 | } | |
12a7367e | 199 | |
b109e79a ILT |
200 | return ret; |
201 | } | |
5a17353c | 202 | |
b109e79a | 203 | #endif /* defined (HAVE_GETRUSAGE) */ |
5a17353c | 204 | |
b109e79a ILT |
205 | #else /* ! defined (HAVE_WAITPID) */ |
206 | ||
207 | struct status_list | |
208 | { | |
209 | struct status_list *next; | |
210 | pid_t pid; | |
211 | int status; | |
212 | struct pex_time time; | |
213 | }; | |
214 | ||
215 | static pid_t | |
216 | pex_wait (struct pex_obj *obj, pid_t pid, int *status, struct pex_time *time) | |
217 | { | |
218 | struct status_list **pp; | |
219 | ||
220 | for (pp = (struct status_list **) &obj->sysdep; | |
221 | *pp != NULL; | |
222 | pp = &(*pp)->next) | |
5a17353c | 223 | { |
b109e79a | 224 | if ((*pp)->pid == pid) |
5a17353c | 225 | { |
b109e79a ILT |
226 | struct status_list *p; |
227 | ||
228 | p = *pp; | |
229 | *status = p->status; | |
230 | if (time != NULL) | |
231 | *time = p->time; | |
232 | *pp = p->next; | |
233 | free (p); | |
234 | return pid; | |
5a17353c | 235 | } |
5a17353c | 236 | } |
b109e79a ILT |
237 | |
238 | while (1) | |
5a17353c | 239 | { |
b109e79a ILT |
240 | pid_t cpid; |
241 | struct status_list *psl; | |
242 | struct pex_time pt; | |
243 | #ifdef HAVE_GETRUSAGE | |
244 | struct rusage r1, r2; | |
245 | #endif | |
246 | ||
247 | if (time != NULL) | |
248 | { | |
249 | #ifdef HAVE_GETRUSAGE | |
250 | getrusage (RUSAGE_CHILDREN, &r1); | |
251 | #else | |
252 | memset (&pt, 0, sizeof (struct pex_time)); | |
253 | #endif | |
254 | } | |
255 | ||
256 | cpid = wait (status); | |
257 | ||
258 | #ifdef HAVE_GETRUSAGE | |
259 | if (time != NULL && cpid >= 0) | |
260 | { | |
261 | getrusage (RUSAGE_CHILDREN, &r2); | |
262 | ||
263 | pt.user_seconds = r2.ru_utime.tv_sec - r1.ru_utime.tv_sec; | |
264 | pt.user_microseconds = r2.ru_utime.tv_usec - r1.ru_utime.tv_usec; | |
265 | if (pt.user_microseconds < 0) | |
266 | { | |
267 | --pt.user_seconds; | |
268 | pt.user_microseconds += 1000000; | |
269 | } | |
270 | ||
271 | pt.system_seconds = r2.ru_stime.tv_sec - r1.ru_stime.tv_sec; | |
272 | pt.system_microseconds = r2.ru_stime.tv_usec - r1.ru_stime.tv_usec; | |
273 | if (pt.system_microseconds < 0) | |
274 | { | |
275 | --pt.system_seconds; | |
276 | pt.system_microseconds += 1000000; | |
277 | } | |
278 | } | |
279 | #endif | |
280 | ||
281 | if (cpid < 0 || cpid == pid) | |
282 | { | |
283 | if (time != NULL) | |
284 | *time = pt; | |
285 | return cpid; | |
286 | } | |
287 | ||
abf6a75b | 288 | psl = XNEW (struct status_list); |
b109e79a ILT |
289 | psl->pid = cpid; |
290 | psl->status = *status; | |
291 | if (time != NULL) | |
292 | psl->time = pt; | |
293 | psl->next = (struct status_list *) obj->sysdep; | |
294 | obj->sysdep = (void *) psl; | |
5a17353c | 295 | } |
b109e79a ILT |
296 | } |
297 | ||
298 | #endif /* ! defined (HAVE_WAITPID) */ | |
299 | #endif /* ! defined (HAVE_WAIT4) */ | |
300 | ||
b109e79a | 301 | static int pex_unix_open_read (struct pex_obj *, const char *, int); |
b55f9678 | 302 | static int pex_unix_open_write (struct pex_obj *, const char *, int, int); |
29d89e07 | 303 | static pid_t pex_unix_exec_child (struct pex_obj *, int, const char *, |
014a8caf | 304 | char * const *, char * const *, |
cb6c09ac DD |
305 | int, int, int, int, |
306 | const char **, int *); | |
b109e79a | 307 | static int pex_unix_close (struct pex_obj *, int); |
29d89e07 | 308 | static int pex_unix_wait (struct pex_obj *, pid_t, int *, struct pex_time *, |
b109e79a ILT |
309 | int, const char **, int *); |
310 | static int pex_unix_pipe (struct pex_obj *, int *, int); | |
311 | static FILE *pex_unix_fdopenr (struct pex_obj *, int, int); | |
3db2e6dd | 312 | static FILE *pex_unix_fdopenw (struct pex_obj *, int, int); |
b109e79a ILT |
313 | static void pex_unix_cleanup (struct pex_obj *); |
314 | ||
315 | /* The list of functions we pass to the common routines. */ | |
316 | ||
317 | const struct pex_funcs funcs = | |
318 | { | |
319 | pex_unix_open_read, | |
320 | pex_unix_open_write, | |
321 | pex_unix_exec_child, | |
322 | pex_unix_close, | |
323 | pex_unix_wait, | |
324 | pex_unix_pipe, | |
325 | pex_unix_fdopenr, | |
3db2e6dd | 326 | pex_unix_fdopenw, |
b109e79a ILT |
327 | pex_unix_cleanup |
328 | }; | |
329 | ||
330 | /* Return a newly initialized pex_obj structure. */ | |
331 | ||
332 | struct pex_obj * | |
333 | pex_init (int flags, const char *pname, const char *tempbase) | |
334 | { | |
335 | return pex_init_common (flags, pname, tempbase, &funcs); | |
336 | } | |
337 | ||
338 | /* Open a file for reading. */ | |
339 | ||
340 | static int | |
341 | pex_unix_open_read (struct pex_obj *obj ATTRIBUTE_UNUSED, const char *name, | |
342 | int binary ATTRIBUTE_UNUSED) | |
343 | { | |
344 | return open (name, O_RDONLY); | |
345 | } | |
346 | ||
347 | /* Open a file for writing. */ | |
348 | ||
349 | static int | |
350 | pex_unix_open_write (struct pex_obj *obj ATTRIBUTE_UNUSED, const char *name, | |
b55f9678 | 351 | int binary ATTRIBUTE_UNUSED, int append) |
b109e79a ILT |
352 | { |
353 | /* Note that we can't use O_EXCL here because gcc may have already | |
354 | created the temporary file via make_temp_file. */ | |
b55f9678 IB |
355 | return open (name, O_WRONLY | O_CREAT |
356 | | (append ? O_APPEND : O_TRUNC), PUBLIC_MODE); | |
b109e79a | 357 | } |
5a17353c | 358 | |
b109e79a ILT |
359 | /* Close a file. */ |
360 | ||
361 | static int | |
362 | pex_unix_close (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd) | |
363 | { | |
364 | return close (fd); | |
365 | } | |
366 | ||
b109e79a ILT |
367 | /* Execute a child. */ |
368 | ||
9c55e064 RH |
369 | #if defined(HAVE_SPAWNVE) && defined(HAVE_SPAWNVPE) |
370 | /* Implementation of pex->exec_child using the Cygwin spawn operation. */ | |
371 | ||
372 | /* Subroutine of pex_unix_exec_child. Move OLD_FD to a new file descriptor | |
373 | to be stored in *PNEW_FD, save the flags in *PFLAGS, and arrange for the | |
374 | saved copy to be close-on-exec. Move CHILD_FD into OLD_FD. If CHILD_FD | |
375 | is -1, OLD_FD is to be closed. Return -1 on error. */ | |
376 | ||
377 | static int | |
378 | save_and_install_fd(int *pnew_fd, int *pflags, int old_fd, int child_fd) | |
379 | { | |
380 | int new_fd, flags; | |
381 | ||
382 | flags = fcntl (old_fd, F_GETFD); | |
383 | ||
384 | /* If we could not retrieve the flags, then OLD_FD was not open. */ | |
385 | if (flags < 0) | |
386 | { | |
387 | new_fd = -1, flags = 0; | |
388 | if (child_fd >= 0 && dup2 (child_fd, old_fd) < 0) | |
389 | return -1; | |
390 | } | |
391 | /* If we wish to close OLD_FD, just mark it CLOEXEC. */ | |
392 | else if (child_fd == -1) | |
393 | { | |
394 | new_fd = old_fd; | |
395 | if ((flags & FD_CLOEXEC) == 0 && fcntl (old_fd, F_SETFD, FD_CLOEXEC) < 0) | |
396 | return -1; | |
397 | } | |
398 | /* Otherwise we need to save a copy of OLD_FD before installing CHILD_FD. */ | |
399 | else | |
400 | { | |
401 | #ifdef F_DUPFD_CLOEXEC | |
402 | new_fd = fcntl (old_fd, F_DUPFD_CLOEXEC, 3); | |
403 | if (new_fd < 0) | |
404 | return -1; | |
405 | #else | |
406 | /* Prefer F_DUPFD over dup in order to avoid getting a new fd | |
407 | in the range 0-2, right where a new stderr fd might get put. */ | |
408 | new_fd = fcntl (old_fd, F_DUPFD, 3); | |
409 | if (new_fd < 0) | |
410 | return -1; | |
411 | if (fcntl (new_fd, F_SETFD, FD_CLOEXEC) < 0) | |
412 | return -1; | |
413 | #endif | |
414 | if (dup2 (child_fd, old_fd) < 0) | |
415 | return -1; | |
416 | } | |
417 | ||
418 | *pflags = flags; | |
419 | if (pnew_fd) | |
420 | *pnew_fd = new_fd; | |
421 | else if (new_fd != old_fd) | |
422 | abort (); | |
423 | ||
424 | return 0; | |
425 | } | |
426 | ||
427 | /* Subroutine of pex_unix_exec_child. Move SAVE_FD back to OLD_FD | |
428 | restoring FLAGS. If SAVE_FD < 0, OLD_FD is to be closed. */ | |
429 | ||
430 | static int | |
431 | restore_fd(int old_fd, int save_fd, int flags) | |
432 | { | |
433 | /* For SAVE_FD < 0, all we have to do is restore the | |
434 | "closed-ness" of the original. */ | |
435 | if (save_fd < 0) | |
436 | return close (old_fd); | |
437 | ||
438 | /* For SAVE_FD == OLD_FD, all we have to do is restore the | |
439 | original setting of the CLOEXEC flag. */ | |
440 | if (save_fd == old_fd) | |
441 | { | |
442 | if (flags & FD_CLOEXEC) | |
443 | return 0; | |
444 | return fcntl (old_fd, F_SETFD, flags); | |
445 | } | |
446 | ||
447 | /* Otherwise we have to move the descriptor back, restore the flags, | |
448 | and close the saved copy. */ | |
449 | #ifdef HAVE_DUP3 | |
450 | if (flags == FD_CLOEXEC) | |
451 | { | |
452 | if (dup3 (save_fd, old_fd, O_CLOEXEC) < 0) | |
453 | return -1; | |
454 | } | |
455 | else | |
456 | #endif | |
457 | { | |
458 | if (dup2 (save_fd, old_fd) < 0) | |
459 | return -1; | |
460 | if (flags != 0 && fcntl (old_fd, F_SETFD, flags) < 0) | |
461 | return -1; | |
462 | } | |
463 | return close (save_fd); | |
464 | } | |
465 | ||
466 | static pid_t | |
467 | pex_unix_exec_child (struct pex_obj *obj ATTRIBUTE_UNUSED, | |
468 | int flags, const char *executable, | |
469 | char * const * argv, char * const * env, | |
470 | int in, int out, int errdes, int toclose, | |
471 | const char **errmsg, int *err) | |
472 | { | |
473 | int fl_in = 0, fl_out = 0, fl_err = 0, fl_tc = 0; | |
474 | int save_in = -1, save_out = -1, save_err = -1; | |
475 | int max, retries; | |
476 | pid_t pid; | |
477 | ||
478 | if (flags & PEX_STDERR_TO_STDOUT) | |
479 | errdes = out; | |
480 | ||
481 | /* We need the three standard file descriptors to be set up as for | |
482 | the child before we perform the spawn. The file descriptors for | |
483 | the parent need to be moved and marked for close-on-exec. */ | |
484 | if (in != STDIN_FILE_NO | |
485 | && save_and_install_fd (&save_in, &fl_in, STDIN_FILE_NO, in) < 0) | |
486 | goto error_dup2; | |
487 | if (out != STDOUT_FILE_NO | |
488 | && save_and_install_fd (&save_out, &fl_out, STDOUT_FILE_NO, out) < 0) | |
489 | goto error_dup2; | |
490 | if (errdes != STDERR_FILE_NO | |
491 | && save_and_install_fd (&save_err, &fl_err, STDERR_FILE_NO, errdes) < 0) | |
492 | goto error_dup2; | |
493 | if (toclose >= 0 | |
494 | && save_and_install_fd (NULL, &fl_tc, toclose, -1) < 0) | |
495 | goto error_dup2; | |
496 | ||
497 | /* Now that we've moved the file descriptors for the child into place, | |
498 | close the originals. Be careful not to close any of the standard | |
499 | file descriptors that we just set up. */ | |
500 | max = -1; | |
501 | if (errdes >= 0) | |
502 | max = STDERR_FILE_NO; | |
503 | else if (out >= 0) | |
504 | max = STDOUT_FILE_NO; | |
505 | else if (in >= 0) | |
506 | max = STDIN_FILE_NO; | |
507 | if (in > max) | |
508 | close (in); | |
509 | if (out > max) | |
510 | close (out); | |
511 | if (errdes > max && errdes != out) | |
512 | close (errdes); | |
513 | ||
514 | /* If we were not given an environment, use the global environment. */ | |
515 | if (env == NULL) | |
516 | env = environ; | |
517 | ||
518 | /* Launch the program. If we get EAGAIN (normally out of pid's), try | |
519 | again a few times with increasing backoff times. */ | |
520 | retries = 0; | |
521 | while (1) | |
522 | { | |
523 | typedef const char * const *cc_cp; | |
524 | ||
525 | if (flags & PEX_SEARCH) | |
526 | pid = spawnvpe (_P_NOWAITO, executable, (cc_cp)argv, (cc_cp)env); | |
527 | else | |
528 | pid = spawnve (_P_NOWAITO, executable, (cc_cp)argv, (cc_cp)env); | |
529 | ||
530 | if (pid > 0) | |
531 | break; | |
532 | ||
533 | *err = errno; | |
534 | *errmsg = "spawn"; | |
535 | if (errno != EAGAIN || ++retries == 4) | |
536 | return (pid_t) -1; | |
537 | sleep (1 << retries); | |
538 | } | |
539 | ||
540 | /* Success. Restore the parent's file descriptors that we saved above. */ | |
541 | if (toclose >= 0 | |
542 | && restore_fd (toclose, toclose, fl_tc) < 0) | |
543 | goto error_dup2; | |
544 | if (in != STDIN_FILE_NO | |
545 | && restore_fd (STDIN_FILE_NO, save_in, fl_in) < 0) | |
546 | goto error_dup2; | |
547 | if (out != STDOUT_FILE_NO | |
548 | && restore_fd (STDOUT_FILE_NO, save_out, fl_out) < 0) | |
549 | goto error_dup2; | |
550 | if (errdes != STDERR_FILE_NO | |
551 | && restore_fd (STDERR_FILE_NO, save_err, fl_err) < 0) | |
552 | goto error_dup2; | |
553 | ||
554 | return pid; | |
555 | ||
556 | error_dup2: | |
557 | *err = errno; | |
558 | *errmsg = "dup2"; | |
559 | return (pid_t) -1; | |
560 | } | |
561 | ||
562 | #else | |
563 | /* Implementation of pex->exec_child using standard vfork + exec. */ | |
564 | ||
29d89e07 | 565 | static pid_t |
b109e79a | 566 | pex_unix_exec_child (struct pex_obj *obj, int flags, const char *executable, |
014a8caf DD |
567 | char * const * argv, char * const * env, |
568 | int in, int out, int errdes, | |
cb6c09ac | 569 | int toclose, const char **errmsg, int *err) |
b109e79a | 570 | { |
af03af8f NC |
571 | pid_t pid = -1; |
572 | /* Tuple to communicate error from child to parent. We can safely | |
573 | transfer string literal pointers as both run with identical | |
574 | address mappings. */ | |
575 | struct fn_err | |
576 | { | |
577 | const char *fn; | |
578 | int err; | |
579 | }; | |
580 | volatile int do_pipe = 0; | |
581 | volatile int pipes[2]; /* [0]:reader,[1]:writer. */ | |
582 | #ifdef O_CLOEXEC | |
583 | do_pipe = 1; | |
584 | #endif | |
585 | if (do_pipe) | |
586 | { | |
587 | #ifdef HAVE_PIPE2 | |
588 | if (pipe2 ((int *)pipes, O_CLOEXEC)) | |
589 | do_pipe = 0; | |
590 | #else | |
591 | if (pipe ((int *)pipes)) | |
592 | do_pipe = 0; | |
593 | else | |
594 | { | |
595 | if (fcntl (pipes[1], F_SETFD, FD_CLOEXEC) == -1) | |
596 | { | |
597 | close (pipes[0]); | |
598 | close (pipes[1]); | |
599 | do_pipe = 0; | |
600 | } | |
601 | } | |
602 | #endif | |
603 | } | |
014a8caf | 604 | |
b109e79a ILT |
605 | /* We declare these to be volatile to avoid warnings from gcc about |
606 | them being clobbered by vfork. */ | |
af03af8f | 607 | volatile int sleep_interval = 1; |
b109e79a | 608 | volatile int retries; |
12a7367e | 609 | |
16b8170d DE |
610 | /* We vfork and then set environ in the child before calling execvp. |
611 | This clobbers the parent's environ so we need to restore it. | |
612 | It would be nice to use one of the exec* functions that takes an | |
af03af8f NC |
613 | environment as a parameter, but that may have portability |
614 | issues. It is marked volatile so the child doesn't consider it a | |
615 | dead variable and therefore clobber where ever it is stored. */ | |
616 | char **volatile save_environ = environ; | |
16b8170d | 617 | |
b109e79a | 618 | for (retries = 0; retries < 4; ++retries) |
5a17353c | 619 | { |
12a7367e | 620 | pid = vfork (); |
5a17353c DD |
621 | if (pid >= 0) |
622 | break; | |
623 | sleep (sleep_interval); | |
624 | sleep_interval *= 2; | |
625 | } | |
626 | ||
627 | switch (pid) | |
628 | { | |
629 | case -1: | |
af03af8f NC |
630 | if (do_pipe) |
631 | { | |
632 | close (pipes[0]); | |
633 | close (pipes[1]); | |
634 | } | |
b109e79a ILT |
635 | *err = errno; |
636 | *errmsg = VFORK_STRING; | |
29d89e07 | 637 | return (pid_t) -1; |
5a17353c | 638 | |
b109e79a ILT |
639 | case 0: |
640 | /* Child process. */ | |
af03af8f NC |
641 | { |
642 | struct fn_err failed; | |
643 | failed.fn = NULL; | |
644 | ||
645 | if (do_pipe) | |
646 | close (pipes[0]); | |
647 | if (!failed.fn && in != STDIN_FILE_NO) | |
648 | { | |
649 | if (dup2 (in, STDIN_FILE_NO) < 0) | |
650 | failed.fn = "dup2", failed.err = errno; | |
651 | else if (close (in) < 0) | |
652 | failed.fn = "close", failed.err = errno; | |
653 | } | |
654 | if (!failed.fn && out != STDOUT_FILE_NO) | |
655 | { | |
656 | if (dup2 (out, STDOUT_FILE_NO) < 0) | |
657 | failed.fn = "dup2", failed.err = errno; | |
658 | else if (close (out) < 0) | |
659 | failed.fn = "close", failed.err = errno; | |
660 | } | |
661 | if (!failed.fn && errdes != STDERR_FILE_NO) | |
662 | { | |
663 | if (dup2 (errdes, STDERR_FILE_NO) < 0) | |
664 | failed.fn = "dup2", failed.err = errno; | |
665 | else if (close (errdes) < 0) | |
666 | failed.fn = "close", failed.err = errno; | |
667 | } | |
668 | if (!failed.fn && toclose >= 0) | |
669 | { | |
670 | if (close (toclose) < 0) | |
671 | failed.fn = "close", failed.err = errno; | |
672 | } | |
673 | if (!failed.fn && (flags & PEX_STDERR_TO_STDOUT) != 0) | |
674 | { | |
675 | if (dup2 (STDOUT_FILE_NO, STDERR_FILE_NO) < 0) | |
676 | failed.fn = "dup2", failed.err = errno; | |
677 | } | |
678 | if (!failed.fn) | |
679 | { | |
680 | if (env) | |
681 | /* NOTE: In a standard vfork implementation this clobbers | |
682 | the parent's copy of environ "too" (in reality there's | |
683 | only one copy). This is ok as we restore it below. */ | |
684 | environ = (char**) env; | |
685 | if ((flags & PEX_SEARCH) != 0) | |
686 | { | |
687 | execvp (executable, to_ptr32 (argv)); | |
688 | failed.fn = "execvp", failed.err = errno; | |
689 | } | |
690 | else | |
691 | { | |
692 | execv (executable, to_ptr32 (argv)); | |
693 | failed.fn = "execv", failed.err = errno; | |
694 | } | |
695 | } | |
696 | ||
697 | /* Something failed, report an error. We don't use stdio | |
698 | routines, because we might be here due to a vfork call. */ | |
699 | ssize_t retval = 0; | |
700 | ||
701 | if (!do_pipe | |
702 | || write (pipes[1], &failed, sizeof (failed)) != sizeof (failed)) | |
703 | { | |
704 | /* The parent will not see our scream above, so write to | |
705 | stdout. */ | |
706 | #define writeerr(s) (retval |= write (STDERR_FILE_NO, s, strlen (s))) | |
707 | writeerr (obj->pname); | |
708 | writeerr (": error trying to exec '"); | |
709 | writeerr (executable); | |
710 | writeerr ("': "); | |
711 | writeerr (failed.fn); | |
712 | writeerr (": "); | |
713 | writeerr (xstrerror (failed.err)); | |
714 | writeerr ("\n"); | |
715 | #undef writeerr | |
716 | } | |
12a7367e | 717 | |
af03af8f NC |
718 | /* Exit with -2 if the error output failed, too. */ |
719 | _exit (retval < 0 ? -2 : -1); | |
720 | } | |
5a17353c | 721 | /* NOTREACHED */ |
29d89e07 | 722 | return (pid_t) -1; |
5a17353c DD |
723 | |
724 | default: | |
b109e79a | 725 | /* Parent process. */ |
af03af8f NC |
726 | { |
727 | /* Restore environ. Note that the parent either doesn't run | |
728 | until the child execs/exits (standard vfork behaviour), or | |
729 | if it does run then vfork is behaving more like fork. In | |
730 | either case we needn't worry about clobbering the child's | |
731 | copy of environ. */ | |
732 | environ = save_environ; | |
733 | ||
734 | struct fn_err failed; | |
735 | failed.fn = NULL; | |
736 | if (do_pipe) | |
737 | { | |
738 | close (pipes[1]); | |
739 | ssize_t len = read (pipes[0], &failed, sizeof (failed)); | |
740 | if (len < 0) | |
741 | failed.fn = NULL; | |
742 | close (pipes[0]); | |
743 | } | |
744 | ||
745 | if (!failed.fn && in != STDIN_FILE_NO) | |
b109e79a | 746 | if (close (in) < 0) |
af03af8f NC |
747 | failed.fn = "close", failed.err = errno; |
748 | if (!failed.fn && out != STDOUT_FILE_NO) | |
b109e79a | 749 | if (close (out) < 0) |
af03af8f NC |
750 | failed.fn = "close", failed.err = errno; |
751 | if (!failed.fn && errdes != STDERR_FILE_NO) | |
b109e79a | 752 | if (close (errdes) < 0) |
af03af8f NC |
753 | failed.fn = "close", failed.err = errno; |
754 | ||
755 | if (failed.fn) | |
756 | { | |
757 | *err = failed.err; | |
758 | *errmsg = failed.fn; | |
759 | return (pid_t) -1; | |
760 | } | |
761 | } | |
29d89e07 | 762 | return pid; |
5a17353c DD |
763 | } |
764 | } | |
9c55e064 | 765 | #endif /* SPAWN */ |
5a17353c | 766 | |
b109e79a ILT |
767 | /* Wait for a child process to complete. */ |
768 | ||
769 | static int | |
29d89e07 | 770 | pex_unix_wait (struct pex_obj *obj, pid_t pid, int *status, |
b109e79a ILT |
771 | struct pex_time *time, int done, const char **errmsg, |
772 | int *err) | |
5a17353c | 773 | { |
b109e79a ILT |
774 | /* If we are cleaning up when the caller didn't retrieve process |
775 | status for some reason, encourage the process to go away. */ | |
776 | if (done) | |
777 | kill (pid, SIGTERM); | |
778 | ||
779 | if (pex_wait (obj, pid, status, time) < 0) | |
780 | { | |
781 | *err = errno; | |
782 | *errmsg = "wait"; | |
783 | return -1; | |
784 | } | |
785 | ||
786 | return 0; | |
787 | } | |
788 | ||
789 | /* Create a pipe. */ | |
790 | ||
791 | static int | |
792 | pex_unix_pipe (struct pex_obj *obj ATTRIBUTE_UNUSED, int *p, | |
793 | int binary ATTRIBUTE_UNUSED) | |
794 | { | |
795 | return pipe (p); | |
796 | } | |
797 | ||
798 | /* Get a FILE pointer to read from a file descriptor. */ | |
799 | ||
800 | static FILE * | |
801 | pex_unix_fdopenr (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd, | |
802 | int binary ATTRIBUTE_UNUSED) | |
803 | { | |
804 | return fdopen (fd, "r"); | |
805 | } | |
806 | ||
3db2e6dd DD |
807 | static FILE * |
808 | pex_unix_fdopenw (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd, | |
809 | int binary ATTRIBUTE_UNUSED) | |
810 | { | |
811 | if (fcntl (fd, F_SETFD, FD_CLOEXEC) < 0) | |
812 | return NULL; | |
813 | return fdopen (fd, "w"); | |
814 | } | |
815 | ||
b109e79a ILT |
816 | static void |
817 | pex_unix_cleanup (struct pex_obj *obj ATTRIBUTE_UNUSED) | |
818 | { | |
819 | #if !defined (HAVE_WAIT4) && !defined (HAVE_WAITPID) | |
820 | while (obj->sysdep != NULL) | |
821 | { | |
822 | struct status_list *this; | |
823 | struct status_list *next; | |
824 | ||
825 | this = (struct status_list *) obj->sysdep; | |
826 | next = this->next; | |
827 | free (this); | |
828 | obj->sysdep = (void *) next; | |
829 | } | |
830 | #endif | |
5a17353c | 831 | } |