This repository has been archived by the owner on Nov 17, 2020. It is now read-only.
-
Notifications
You must be signed in to change notification settings - Fork 1
/
gspawn.c
1408 lines (1227 loc) · 41.4 KB
/
gspawn.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/* gspawn.c - Process launching
*
* Copyright 2000 Red Hat, Inc.
* g_execvpe implementation based on GNU libc execvp:
* Copyright 1991, 92, 95, 96, 97, 98, 99 Free Software Foundation, Inc.
*
* GLib is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* GLib is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with GLib; see the file COPYING.LIB. If not, write
* to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include "glib.h"
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <string.h>
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif /* HAVE_SYS_SELECT_H */
#include "glibintl.h"
static gint g_execute (const gchar *file,
gchar **argv,
gchar **envp,
gboolean search_path);
static gboolean make_pipe (gint p[2],
GError **error);
static gboolean fork_exec_with_pipes (gboolean intermediate_child,
const gchar *working_directory,
gchar **argv,
gchar **envp,
gboolean close_descriptors,
gboolean search_path,
gboolean stdout_to_null,
gboolean stderr_to_null,
gboolean child_inherits_stdin,
gboolean file_and_argv_zero,
GSpawnChildSetupFunc child_setup,
gpointer user_data,
gint *child_pid,
gint *standard_input,
gint *standard_output,
gint *standard_error,
GError **error);
GQuark
g_spawn_error_quark (void)
{
static GQuark quark = 0;
if (quark == 0)
quark = g_quark_from_static_string ("g-exec-error-quark");
return quark;
}
/**
* g_spawn_async:
* @working_directory: child's current working directory, or NULL to inherit parent's
* @argv: child's argument vector
* @envp: child's environment, or NULL to inherit parent's
* @flags: flags from #GSpawnFlags
* @child_setup: function to run in the child just before exec()
* @user_data: user data for @child_setup
* @child_pid: return location for child process ID, or NULL
* @error: return location for error
*
* See g_spawn_async_with_pipes() for a full description; this function
* simply calls the g_spawn_async_with_pipes() without any pipes.
*
* Return value: TRUE on success, FALSE if error is set
**/
gboolean
g_spawn_async (const gchar *working_directory,
gchar **argv,
gchar **envp,
GSpawnFlags flags,
GSpawnChildSetupFunc child_setup,
gpointer user_data,
gint *child_pid,
GError **error)
{
g_return_val_if_fail (argv != NULL, FALSE);
return g_spawn_async_with_pipes (working_directory,
argv, envp,
flags,
child_setup,
user_data,
child_pid,
NULL, NULL, NULL,
error);
}
/* Avoids a danger in threaded situations (calling close()
* on a file descriptor twice, and another thread has
* re-opened it since the first close)
*/
static gint
close_and_invalidate (gint *fd)
{
gint ret;
ret = close (*fd);
*fd = -1;
return ret;
}
typedef enum
{
READ_FAILED = 0, /* FALSE */
READ_OK,
READ_EOF
} ReadResult;
static ReadResult
read_data (GString *str,
gint fd,
GError **error)
{
gint bytes;
gchar buf[4096];
again:
bytes = read (fd, &buf, 4096);
if (bytes == 0)
return READ_EOF;
else if (bytes > 0)
{
g_string_append_len (str, buf, bytes);
return READ_OK;
}
else if (bytes < 0 && errno == EINTR)
goto again;
else if (bytes < 0)
{
g_set_error (error,
G_SPAWN_ERROR,
G_SPAWN_ERROR_READ,
_("Failed to read data from child process (%s)"),
g_strerror (errno));
return READ_FAILED;
}
else
return READ_OK;
}
/**
* g_spawn_sync:
* @working_directory: child's current working directory, or NULL to inherit parent's
* @argv: child's argument vector
* @envp: child's environment, or NULL to inherit parent's
* @flags: flags from #GSpawnFlags
* @child_setup: function to run in the child just before exec()
* @user_data: user data for @child_setup
* @standard_output: return location for child output
* @standard_error: return location for child error messages
* @exit_status: child exit status, as returned by waitpid()
* @error: return location for error
*
* Executes a child synchronously (waits for the child to exit before returning).
* All output from the child is stored in @standard_output and @standard_error,
* if those parameters are non-NULL. If @exit_status is non-NULL, the exit status
* of the child is stored there as it would be by waitpid(); standard UNIX
* macros such as WIFEXITED() and WEXITSTATUS() must be used to evaluate the
* exit status. If an error occurs, no data is returned in @standard_output,
* @standard_error, or @exit_status.
*
* This function calls g_spawn_async_with_pipes() internally; see that function
* for full details on the other parameters.
*
* Return value: TRUE on success, FALSE if an error was set.
**/
gboolean
g_spawn_sync (const gchar *working_directory,
gchar **argv,
gchar **envp,
GSpawnFlags flags,
GSpawnChildSetupFunc child_setup,
gpointer user_data,
gchar **standard_output,
gchar **standard_error,
gint *exit_status,
GError **error)
{
gint outpipe = -1;
gint errpipe = -1;
gint pid;
fd_set fds;
gint ret;
GString *outstr = NULL;
GString *errstr = NULL;
gboolean failed;
gint status;
g_return_val_if_fail (argv != NULL, FALSE);
g_return_val_if_fail (!(flags & G_SPAWN_DO_NOT_REAP_CHILD), FALSE);
g_return_val_if_fail (standard_output == NULL ||
!(flags & G_SPAWN_STDOUT_TO_DEV_NULL), FALSE);
g_return_val_if_fail (standard_error == NULL ||
!(flags & G_SPAWN_STDERR_TO_DEV_NULL), FALSE);
/* Just to ensure segfaults if callers try to use
* these when an error is reported.
*/
if (standard_output)
*standard_output = NULL;
if (standard_error)
*standard_error = NULL;
if (!fork_exec_with_pipes (FALSE,
working_directory,
argv,
envp,
!(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN),
(flags & G_SPAWN_SEARCH_PATH) != 0,
(flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0,
(flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0,
(flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0,
(flags & G_SPAWN_FILE_AND_ARGV_ZERO) != 0,
child_setup,
user_data,
&pid,
NULL,
standard_output ? &outpipe : NULL,
standard_error ? &errpipe : NULL,
error))
return FALSE;
/* Read data from child. */
failed = FALSE;
if (outpipe >= 0)
{
outstr = g_string_new ("");
}
if (errpipe >= 0)
{
errstr = g_string_new ("");
}
/* Read data until we get EOF on both pipes. */
while (!failed &&
(outpipe >= 0 ||
errpipe >= 0))
{
ret = 0;
FD_ZERO (&fds);
if (outpipe >= 0)
FD_SET (outpipe, &fds);
if (errpipe >= 0)
FD_SET (errpipe, &fds);
ret = select (MAX (outpipe, errpipe) + 1,
&fds,
NULL, NULL,
NULL /* no timeout */);
if (ret < 0 && errno != EINTR)
{
failed = TRUE;
g_set_error (error,
G_SPAWN_ERROR,
G_SPAWN_ERROR_READ,
_("Unexpected error in select() reading data from a child process (%s)"),
g_strerror (errno));
break;
}
if (outpipe >= 0 && FD_ISSET (outpipe, &fds))
{
switch (read_data (outstr, outpipe, error))
{
case READ_FAILED:
failed = TRUE;
break;
case READ_EOF:
close_and_invalidate (&outpipe);
outpipe = -1;
break;
default:
break;
}
if (failed)
break;
}
if (errpipe >= 0 && FD_ISSET (errpipe, &fds))
{
switch (read_data (errstr, errpipe, error))
{
case READ_FAILED:
failed = TRUE;
break;
case READ_EOF:
close_and_invalidate (&errpipe);
errpipe = -1;
break;
default:
break;
}
if (failed)
break;
}
}
/* These should only be open still if we had an error. */
if (outpipe >= 0)
close_and_invalidate (&outpipe);
if (errpipe >= 0)
close_and_invalidate (&errpipe);
/* Wait for child to exit, even if we have
* an error pending.
*/
again:
ret = waitpid (pid, &status, 0);
if (ret < 0)
{
if (errno == EINTR)
goto again;
else if (errno == ECHILD)
{
if (exit_status)
{
g_warning ("In call to g_spawn_sync(), exit status of a child process was requested but SIGCHLD action was set to SIG_IGN and ECHILD was received by waitpid(), so exit status can't be returned. This is a bug in the program calling g_spawn_sync(); either don't request the exit status, or don't set the SIGCHLD action.");
}
else
{
/* We don't need the exit status. */
}
}
else
{
if (!failed) /* avoid error pileups */
{
failed = TRUE;
g_set_error (error,
G_SPAWN_ERROR,
G_SPAWN_ERROR_READ,
_("Unexpected error in waitpid() (%s)"),
g_strerror (errno));
}
}
}
if (failed)
{
if (outstr)
g_string_free (outstr, TRUE);
if (errstr)
g_string_free (errstr, TRUE);
return FALSE;
}
else
{
if (exit_status)
*exit_status = status;
if (standard_output)
*standard_output = g_string_free (outstr, FALSE);
if (standard_error)
*standard_error = g_string_free (errstr, FALSE);
return TRUE;
}
}
/**
* g_spawn_async_with_pipes:
* @working_directory: child's current working directory, or NULL to inherit parent's
* @argv: child's argument vector
* @envp: child's environment, or NULL to inherit parent's
* @flags: flags from #GSpawnFlags
* @child_setup: function to run in the child just before exec()
* @user_data: user data for @child_setup
* @child_pid: return location for child process ID, or NULL
* @standard_input: return location for file descriptor to write to child's stdin, or NULL
* @standard_output: return location for file descriptor to read child's stdout, or NULL
* @standard_error: return location for file descriptor to read child's stderr, or NULL
* @error: return location for error
*
* Executes a child program asynchronously (your program will not
* block waiting for the child to exit). The child program is
* specified by the only argument that must be provided, @argv. @argv
* should be a NULL-terminated array of strings, to be passed as the
* argument vector for the child. The first string in @argv is of
* course the name of the program to execute. By default, the name of
* the program must be a full path; the PATH shell variable will only
* be searched if you pass the %G_SPAWN_SEARCH_PATH flag.
*
* @envp is a NULL-terminated array of strings, where each string
* has the form <literal>KEY=VALUE</literal>. This will become
* the child's environment. If @envp is NULL, the child inherits its
* parent's environment.
*
* @flags should be the bitwise OR of any flags you want to affect the
* function's behavior. The %G_SPAWN_DO_NOT_REAP_CHILD means that the
* child will not be automatically reaped; you must call waitpid() or
* handle SIGCHLD yourself, or the child will become a zombie.
* %G_SPAWN_LEAVE_DESCRIPTORS_OPEN means that the parent's open file
* descriptors will be inherited by the child; otherwise all
* descriptors except stdin/stdout/stderr will be closed before
* calling exec() in the child. %G_SPAWN_SEARCH_PATH means that
* <literal>argv[0]</literal> need not be an absolute path, it
* will be looked for in the user's PATH. %G_SPAWN_STDOUT_TO_DEV_NULL
* means that the child's standad output will be discarded, instead
* of going to the same location as the parent's standard output.
* %G_SPAWN_STDERR_TO_DEV_NULL means that the child's standard error
* will be discarded. %G_SPAWN_CHILD_INHERITS_STDIN means that
* the child will inherit the parent's standard input (by default,
* the child's standard input is attached to /dev/null).
* %G_SPAWN_FILE_AND_ARGV_ZERO means that the first element of @argv is
* the file to execute, while the remaining elements are the
* actual argument vector to pass to the file. Normally
* g_spawn_async_with_pipes() uses @argv[0] as the file to execute, and
* passes all of @argv to the child.
*
* @child_setup and @user_data are a function and user data to be
* called in the child after GLib has performed all the setup it plans
* to perform (including creating pipes, closing file descriptors,
* etc.) but before calling exec(). That is, @child_setup is called
* just before calling exec() in the child. Obviously actions taken in
* this function will only affect the child, not the parent.
*
* If non-NULL, @child_pid will be filled with the child's process
* ID. You can use the process ID to send signals to the child, or
* to waitpid() if you specified the %G_SPAWN_DO_NOT_REAP_CHILD flag.
*
* If non-NULL, the @standard_input, @standard_output, @standard_error
* locations will be filled with file descriptors for writing to the child's
* standard input or reading from its standard output or standard error.
* The caller of g_spawn_async_with_pipes() must close these file descriptors
* when they are no longer in use. If these parameters are NULL, the
* corresponding pipe won't be created.
*
* @error can be NULL to ignore errors, or non-NULL to report errors.
* If an error is set, the function returns FALSE. Errors
* are reported even if they occur in the child (for example if the
* executable in <literal>argv[0]</literal> is not found). Typically
* the <literal>message</literal> field of returned errors should be displayed
* to users. Possible errors are those from the #G_SPAWN_ERROR domain.
*
* If an error occurs, @child_pid, @standard_input, @standard_output,
* and @standard_error will not be filled with valid values.
*
* Return value: TRUE on success, FALSE if an error was set
**/
gboolean
g_spawn_async_with_pipes (const gchar *working_directory,
gchar **argv,
gchar **envp,
GSpawnFlags flags,
GSpawnChildSetupFunc child_setup,
gpointer user_data,
gint *child_pid,
gint *standard_input,
gint *standard_output,
gint *standard_error,
GError **error)
{
g_return_val_if_fail (argv != NULL, FALSE);
g_return_val_if_fail (standard_output == NULL ||
!(flags & G_SPAWN_STDOUT_TO_DEV_NULL), FALSE);
g_return_val_if_fail (standard_error == NULL ||
!(flags & G_SPAWN_STDERR_TO_DEV_NULL), FALSE);
/* can't inherit stdin if we have an input pipe. */
g_return_val_if_fail (standard_input == NULL ||
!(flags & G_SPAWN_CHILD_INHERITS_STDIN), FALSE);
return fork_exec_with_pipes (!(flags & G_SPAWN_DO_NOT_REAP_CHILD),
working_directory,
argv,
envp,
!(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN),
(flags & G_SPAWN_SEARCH_PATH) != 0,
(flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0,
(flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0,
(flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0,
(flags & G_SPAWN_FILE_AND_ARGV_ZERO) != 0,
child_setup,
user_data,
child_pid,
standard_input,
standard_output,
standard_error,
error);
}
/**
* g_spawn_command_line_sync:
* @command_line: a command line
* @standard_output: return location for child output
* @standard_error: return location for child errors
* @exit_status: return location for child exit status
* @error: return location for errors
*
* A simple version of g_spawn_sync() with little-used parameters
* removed, taking a command line instead of an argument vector. See
* g_spawn_sync() for full details. @command_line will be parsed by
* g_shell_parse_argv(). Unlike g_spawn_sync(), the %G_SPAWN_SEARCH_PATH flag
* is enabled. Note that %G_SPAWN_SEARCH_PATH can have security
* implications, so consider using g_spawn_sync() directly if
* appropriate. Possible errors are those from g_spawn_sync() and those
* from g_shell_parse_argv().
*
* Return value: TRUE on success, FALSE if an error was set
**/
gboolean
g_spawn_command_line_sync (const gchar *command_line,
gchar **standard_output,
gchar **standard_error,
gint *exit_status,
GError **error)
{
gboolean retval;
gchar **argv = 0;
g_return_val_if_fail (command_line != NULL, FALSE);
if (!g_shell_parse_argv (command_line,
NULL, &argv,
error))
return FALSE;
retval = g_spawn_sync (NULL,
argv,
NULL,
G_SPAWN_SEARCH_PATH,
NULL,
NULL,
standard_output,
standard_error,
exit_status,
error);
g_strfreev (argv);
return retval;
}
/**
* g_spawn_command_line_async:
* @command_line: a command line
* @error: return location for errors
*
* A simple version of g_spawn_async() that parses a command line with
* g_shell_parse_argv() and passes it to g_spawn_async(). Runs a
* command line in the background. Unlike g_spawn_async(), the
* %G_SPAWN_SEARCH_PATH flag is enabled, other flags are not. Note
* that %G_SPAWN_SEARCH_PATH can have security implications, so
* consider using g_spawn_async() directly if appropriate. Possible
* errors are those from g_shell_parse_argv() and g_spawn_async().
*
* Return value: TRUE on success, FALSE if error is set.
**/
gboolean
g_spawn_command_line_async (const gchar *command_line,
GError **error)
{
gboolean retval;
gchar **argv = 0;
g_return_val_if_fail (command_line != NULL, FALSE);
if (!g_shell_parse_argv (command_line,
NULL, &argv,
error))
return FALSE;
retval = g_spawn_async (NULL,
argv,
NULL,
G_SPAWN_SEARCH_PATH,
NULL,
NULL,
NULL,
error);
g_strfreev (argv);
return retval;
}
static gint
exec_err_to_g_error (gint en)
{
switch (en)
{
#ifdef EACCES
case EACCES:
return G_SPAWN_ERROR_ACCES;
break;
#endif
#ifdef EPERM
case EPERM:
return G_SPAWN_ERROR_PERM;
break;
#endif
#ifdef E2BIG
case E2BIG:
return G_SPAWN_ERROR_2BIG;
break;
#endif
#ifdef ENOEXEC
case ENOEXEC:
return G_SPAWN_ERROR_NOEXEC;
break;
#endif
#ifdef ENAMETOOLONG
case ENAMETOOLONG:
return G_SPAWN_ERROR_NAMETOOLONG;
break;
#endif
#ifdef ENOENT
case ENOENT:
return G_SPAWN_ERROR_NOENT;
break;
#endif
#ifdef ENOMEM
case ENOMEM:
return G_SPAWN_ERROR_NOMEM;
break;
#endif
#ifdef ENOTDIR
case ENOTDIR:
return G_SPAWN_ERROR_NOTDIR;
break;
#endif
#ifdef ELOOP
case ELOOP:
return G_SPAWN_ERROR_LOOP;
break;
#endif
#ifdef ETXTBUSY
case ETXTBUSY:
return G_SPAWN_ERROR_TXTBUSY;
break;
#endif
#ifdef EIO
case EIO:
return G_SPAWN_ERROR_IO;
break;
#endif
#ifdef ENFILE
case ENFILE:
return G_SPAWN_ERROR_NFILE;
break;
#endif
#ifdef EMFILE
case EMFILE:
return G_SPAWN_ERROR_MFILE;
break;
#endif
#ifdef EINVAL
case EINVAL:
return G_SPAWN_ERROR_INVAL;
break;
#endif
#ifdef EISDIR
case EISDIR:
return G_SPAWN_ERROR_ISDIR;
break;
#endif
#ifdef ELIBBAD
case ELIBBAD:
return G_SPAWN_ERROR_LIBBAD;
break;
#endif
default:
return G_SPAWN_ERROR_FAILED;
break;
}
}
static void
write_err_and_exit (gint fd, gint msg)
{
gint en = errno;
write (fd, &msg, sizeof(msg));
write (fd, &en, sizeof(en));
_exit (1);
}
static void
set_cloexec (gint fd)
{
fcntl (fd, F_SETFD, FD_CLOEXEC);
}
static gint
sane_dup2 (gint fd1, gint fd2)
{
gint ret;
retry:
ret = dup2 (fd1, fd2);
if (ret < 0 && errno == EINTR)
goto retry;
return ret;
}
enum
{
CHILD_CHDIR_FAILED,
CHILD_EXEC_FAILED,
CHILD_DUP2_FAILED,
CHILD_FORK_FAILED
};
static void
do_exec (gint child_err_report_fd,
gint stdin_fd,
gint stdout_fd,
gint stderr_fd,
const gchar *working_directory,
gchar **argv,
gchar **envp,
gboolean close_descriptors,
gboolean search_path,
gboolean stdout_to_null,
gboolean stderr_to_null,
gboolean child_inherits_stdin,
gboolean file_and_argv_zero,
GSpawnChildSetupFunc child_setup,
gpointer user_data)
{
if (working_directory && chdir (working_directory) < 0)
write_err_and_exit (child_err_report_fd,
CHILD_CHDIR_FAILED);
/* Close all file descriptors but stdin stdout and stderr as
* soon as we exec. Note that this includes
* child_err_report_fd, which keeps the parent from blocking
* forever on the other end of that pipe.
*/
if (close_descriptors)
{
gint open_max;
gint i;
open_max = sysconf (_SC_OPEN_MAX);
for (i = 3; i < open_max; i++)
set_cloexec (i);
}
else
{
/* We need to do child_err_report_fd anyway */
set_cloexec (child_err_report_fd);
}
/* Redirect pipes as required */
if (stdin_fd >= 0)
{
/* dup2 can't actually fail here I don't think */
if (sane_dup2 (stdin_fd, 0) < 0)
write_err_and_exit (child_err_report_fd,
CHILD_DUP2_FAILED);
/* ignore this if it doesn't work */
close_and_invalidate (&stdin_fd);
}
else if (!child_inherits_stdin)
{
/* Keep process from blocking on a read of stdin */
gint read_null = open ("/dev/null", O_RDONLY);
sane_dup2 (read_null, 0);
close_and_invalidate (&read_null);
}
if (stdout_fd >= 0)
{
/* dup2 can't actually fail here I don't think */
if (sane_dup2 (stdout_fd, 1) < 0)
write_err_and_exit (child_err_report_fd,
CHILD_DUP2_FAILED);
/* ignore this if it doesn't work */
close_and_invalidate (&stdout_fd);
}
else if (stdout_to_null)
{
gint write_null = open ("/dev/null", O_WRONLY);
sane_dup2 (write_null, 1);
close_and_invalidate (&write_null);
}
if (stderr_fd >= 0)
{
/* dup2 can't actually fail here I don't think */
if (sane_dup2 (stderr_fd, 2) < 0)
write_err_and_exit (child_err_report_fd,
CHILD_DUP2_FAILED);
/* ignore this if it doesn't work */
close_and_invalidate (&stderr_fd);
}
else if (stderr_to_null)
{
gint write_null = open ("/dev/null", O_WRONLY);
sane_dup2 (write_null, 2);
close_and_invalidate (&write_null);
}
/* Call user function just before we exec */
if (child_setup)
{
(* child_setup) (user_data);
}
g_execute (argv[0],
file_and_argv_zero ? argv + 1 : argv,
envp, search_path);
/* Exec failed */
write_err_and_exit (child_err_report_fd,
CHILD_EXEC_FAILED);
}
static gboolean
read_ints (int fd,
gint* buf,
gint n_ints_in_buf,
gint *n_ints_read,
GError **error)
{
gint bytes = 0;
while (TRUE)
{
gint chunk;
if (bytes >= sizeof(gint)*2)
break; /* give up, who knows what happened, should not be
* possible.
*/
again:
chunk = read (fd,
((gchar*)buf) + bytes,
sizeof(gint)*n_ints_in_buf - bytes);
if (chunk < 0 && errno == EINTR)
goto again;
if (chunk < 0)
{
/* Some weird shit happened, bail out */
g_set_error (error,
G_SPAWN_ERROR,
G_SPAWN_ERROR_FAILED,
_("Failed to read from child pipe (%s)"),
g_strerror (errno));
return FALSE;
}
else if (chunk == 0)
break; /* EOF */
else
{
g_assert (chunk > 0);
bytes += chunk;
}
}
*n_ints_read = bytes/4;
return TRUE;
}
static gboolean
fork_exec_with_pipes (gboolean intermediate_child,
const gchar *working_directory,
gchar **argv,
gchar **envp,
gboolean close_descriptors,
gboolean search_path,
gboolean stdout_to_null,
gboolean stderr_to_null,
gboolean child_inherits_stdin,
gboolean file_and_argv_zero,
GSpawnChildSetupFunc child_setup,
gpointer user_data,
gint *child_pid,
gint *standard_input,
gint *standard_output,
gint *standard_error,
GError **error)
{
gint pid;
gint stdin_pipe[2] = { -1, -1 };
gint stdout_pipe[2] = { -1, -1 };
gint stderr_pipe[2] = { -1, -1 };
gint child_err_report_pipe[2] = { -1, -1 };
gint child_pid_report_pipe[2] = { -1, -1 };
gint status;
if (!make_pipe (child_err_report_pipe, error))
return FALSE;
if (intermediate_child && !make_pipe (child_pid_report_pipe, error))
goto cleanup_and_fail;
if (standard_input && !make_pipe (stdin_pipe, error))
goto cleanup_and_fail;
if (standard_output && !make_pipe (stdout_pipe, error))
goto cleanup_and_fail;
if (standard_error && !make_pipe (stderr_pipe, error))
goto cleanup_and_fail;
pid = fork ();
if (pid < 0)
{
g_set_error (error,
G_SPAWN_ERROR,
G_SPAWN_ERROR_FORK,
_("Failed to fork (%s)"),
g_strerror (errno));
goto cleanup_and_fail;
}
else if (pid == 0)
{
/* Immediate child. This may or may not be the child that
* actually execs the new process.
*/
/* Be sure we crash if the parent exits
* and we write to the err_report_pipe
*/
signal (SIGPIPE, SIG_DFL);
/* Close the parent's end of the pipes;
* not needed in the close_descriptors case,
* though
*/
close_and_invalidate (&child_err_report_pipe[0]);
close_and_invalidate (&child_pid_report_pipe[0]);
close_and_invalidate (&stdin_pipe[1]);
close_and_invalidate (&stdout_pipe[0]);
close_and_invalidate (&stderr_pipe[0]);