1 /* gspawn.c - Process launching
3 * Copyright 2000 Red Hat, Inc.
4 * g_execvpe implementation based on GNU libc execvp:
5 * Copyright 1991, 92, 95, 96, 97, 98, 99 Free Software Foundation, Inc.
7 * GLib is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public License as
9 * published by the Free Software Foundation; either version 2 of the
10 * License, or (at your option) any later version.
12 * GLib 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 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with GLib; see the file COPYING.LIB. If not, write
19 * to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
26 #include <sys/types.h>
33 #include <stdlib.h> /* for fdwalk */
36 #ifdef HAVE_SYS_SELECT_H
37 #include <sys/select.h>
38 #endif /* HAVE_SYS_SELECT_H */
40 #ifdef HAVE_SYS_RESOURCE_H
41 #include <sys/resource.h>
42 #endif /* HAVE_SYS_RESOURCE_H */
48 #include "gtestutils.h"
52 static gint g_execute (const gchar *file,
55 gboolean search_path);
57 static gboolean make_pipe (gint p[2],
59 static gboolean fork_exec_with_pipes (gboolean intermediate_child,
60 const gchar *working_directory,
63 gboolean close_descriptors,
65 gboolean stdout_to_null,
66 gboolean stderr_to_null,
67 gboolean child_inherits_stdin,
68 gboolean file_and_argv_zero,
69 GSpawnChildSetupFunc child_setup,
73 gint *standard_output,
78 g_spawn_error_quark (void)
80 return g_quark_from_static_string ("g-exec-error-quark");
85 * @working_directory: child's current working directory, or %NULL to inherit parent's
86 * @argv: child's argument vector
87 * @envp: child's environment, or %NULL to inherit parent's
88 * @flags: flags from #GSpawnFlags
89 * @child_setup: function to run in the child just before exec()
90 * @user_data: user data for @child_setup
91 * @child_pid: return location for child process reference, or %NULL
92 * @error: return location for error
94 * See g_spawn_async_with_pipes() for a full description; this function
95 * simply calls the g_spawn_async_with_pipes() without any pipes.
97 * You should call g_spawn_close_pid() on the returned child process
98 * reference when you don't need it any more.
101 * If you are writing a GTK+ application, and the program you
102 * are spawning is a graphical application, too, then you may
103 * want to use gdk_spawn_on_screen() instead to ensure that
104 * the spawned program opens its windows on the right screen.
107 * <note><para> Note that the returned @child_pid on Windows is a
108 * handle to the child process and not its identifier. Process handles
109 * and process identifiers are different concepts on Windows.
112 * Return value: %TRUE on success, %FALSE if error is set
115 g_spawn_async (const gchar *working_directory,
119 GSpawnChildSetupFunc child_setup,
124 g_return_val_if_fail (argv != NULL, FALSE);
126 return g_spawn_async_with_pipes (working_directory,
136 /* Avoids a danger in threaded situations (calling close()
137 * on a file descriptor twice, and another thread has
138 * re-opened it since the first close)
141 close_and_invalidate (gint *fd)
156 /* Some versions of OS X define READ_OK in public headers */
161 READ_FAILED = 0, /* FALSE */
167 read_data (GString *str,
176 bytes = read (fd, buf, 4096);
182 g_string_append_len (str, buf, bytes);
185 else if (bytes < 0 && errno == EINTR)
194 _("Failed to read data from child process (%s)"),
205 * @working_directory: child's current working directory, or %NULL to inherit parent's
206 * @argv: child's argument vector
207 * @envp: child's environment, or %NULL to inherit parent's
208 * @flags: flags from #GSpawnFlags
209 * @child_setup: function to run in the child just before exec()
210 * @user_data: user data for @child_setup
211 * @standard_output: return location for child output, or %NULL
212 * @standard_error: return location for child error messages, or %NULL
213 * @exit_status: return location for child exit status, as returned by waitpid(), or %NULL
214 * @error: return location for error, or %NULL
216 * Executes a child synchronously (waits for the child to exit before returning).
217 * All output from the child is stored in @standard_output and @standard_error,
218 * if those parameters are non-%NULL. Note that you must set the
219 * %G_SPAWN_STDOUT_TO_DEV_NULL and %G_SPAWN_STDERR_TO_DEV_NULL flags when
220 * passing %NULL for @standard_output and @standard_error.
221 * If @exit_status is non-%NULL, the exit status of the child is stored
222 * there as it would be returned by waitpid(); standard UNIX macros such
223 * as WIFEXITED() and WEXITSTATUS() must be used to evaluate the exit status.
224 * Note that this function call waitpid() even if @exit_status is %NULL, and
225 * does not accept the %G_SPAWN_DO_NOT_REAP_CHILD flag.
226 * If an error occurs, no data is returned in @standard_output,
227 * @standard_error, or @exit_status.
229 * This function calls g_spawn_async_with_pipes() internally; see that
230 * function for full details on the other parameters and details on
231 * how these functions work on Windows.
233 * Return value: %TRUE on success, %FALSE if an error was set.
236 g_spawn_sync (const gchar *working_directory,
240 GSpawnChildSetupFunc child_setup,
242 gchar **standard_output,
243 gchar **standard_error,
252 GString *outstr = NULL;
253 GString *errstr = NULL;
257 g_return_val_if_fail (argv != NULL, FALSE);
258 g_return_val_if_fail (!(flags & G_SPAWN_DO_NOT_REAP_CHILD), FALSE);
259 g_return_val_if_fail (standard_output == NULL ||
260 !(flags & G_SPAWN_STDOUT_TO_DEV_NULL), FALSE);
261 g_return_val_if_fail (standard_error == NULL ||
262 !(flags & G_SPAWN_STDERR_TO_DEV_NULL), FALSE);
264 /* Just to ensure segfaults if callers try to use
265 * these when an error is reported.
268 *standard_output = NULL;
271 *standard_error = NULL;
273 if (!fork_exec_with_pipes (FALSE,
277 !(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN),
278 (flags & G_SPAWN_SEARCH_PATH) != 0,
279 (flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0,
280 (flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0,
281 (flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0,
282 (flags & G_SPAWN_FILE_AND_ARGV_ZERO) != 0,
287 standard_output ? &outpipe : NULL,
288 standard_error ? &errpipe : NULL,
292 /* Read data from child. */
298 outstr = g_string_new (NULL);
303 errstr = g_string_new (NULL);
306 /* Read data until we get EOF on both pipes. */
315 FD_SET (outpipe, &fds);
317 FD_SET (errpipe, &fds);
319 ret = select (MAX (outpipe, errpipe) + 1,
322 NULL /* no timeout */);
324 if (ret < 0 && errno != EINTR)
333 _("Unexpected error in select() reading data from a child process (%s)"),
339 if (outpipe >= 0 && FD_ISSET (outpipe, &fds))
341 switch (read_data (outstr, outpipe, error))
347 close_and_invalidate (&outpipe);
358 if (errpipe >= 0 && FD_ISSET (errpipe, &fds))
360 switch (read_data (errstr, errpipe, error))
366 close_and_invalidate (&errpipe);
378 /* These should only be open still if we had an error. */
381 close_and_invalidate (&outpipe);
383 close_and_invalidate (&errpipe);
385 /* Wait for child to exit, even if we have
390 ret = waitpid (pid, &status, 0);
396 else if (errno == ECHILD)
400 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.");
404 /* We don't need the exit status. */
409 if (!failed) /* avoid error pileups */
418 _("Unexpected error in waitpid() (%s)"),
427 g_string_free (outstr, TRUE);
429 g_string_free (errstr, TRUE);
436 *exit_status = status;
439 *standard_output = g_string_free (outstr, FALSE);
442 *standard_error = g_string_free (errstr, FALSE);
449 * g_spawn_async_with_pipes:
450 * @working_directory: child's current working directory, or %NULL to inherit parent's, in the GLib file name encoding
451 * @argv: child's argument vector, in the GLib file name encoding
452 * @envp: child's environment, or %NULL to inherit parent's, in the GLib file name encoding
453 * @flags: flags from #GSpawnFlags
454 * @child_setup: function to run in the child just before exec()
455 * @user_data: user data for @child_setup
456 * @child_pid: return location for child process ID, or %NULL
457 * @standard_input: return location for file descriptor to write to child's stdin, or %NULL
458 * @standard_output: return location for file descriptor to read child's stdout, or %NULL
459 * @standard_error: return location for file descriptor to read child's stderr, or %NULL
460 * @error: return location for error
462 * Executes a child program asynchronously (your program will not
463 * block waiting for the child to exit). The child program is
464 * specified by the only argument that must be provided, @argv. @argv
465 * should be a %NULL-terminated array of strings, to be passed as the
466 * argument vector for the child. The first string in @argv is of
467 * course the name of the program to execute. By default, the name of
468 * the program must be a full path; the <envar>PATH</envar> shell variable
469 * will only be searched if you pass the %G_SPAWN_SEARCH_PATH flag.
471 * On Windows, note that all the string or string vector arguments to
472 * this function and the other g_spawn*() functions are in UTF-8, the
473 * GLib file name encoding. Unicode characters that are not part of
474 * the system codepage passed in these arguments will be correctly
475 * available in the spawned program only if it uses wide character API
476 * to retrieve its command line. For C programs built with Microsoft's
477 * tools it is enough to make the program have a wmain() instead of
478 * main(). wmain() has a wide character argument vector as parameter.
480 * At least currently, mingw doesn't support wmain(), so if you use
481 * mingw to develop the spawned program, it will have to call the
482 * undocumented function __wgetmainargs() to get the wide character
483 * argument vector and environment. See gspawn-win32-helper.c in the
484 * GLib sources or init.c in the mingw runtime sources for a prototype
485 * for that function. Alternatively, you can retrieve the Win32 system
486 * level wide character command line passed to the spawned program
487 * using the GetCommandLineW() function.
489 * On Windows the low-level child process creation API
490 * <function>CreateProcess()</function> doesn't use argument vectors,
491 * but a command line. The C runtime library's
492 * <function>spawn*()</function> family of functions (which
493 * g_spawn_async_with_pipes() eventually calls) paste the argument
494 * vector elements together into a command line, and the C runtime startup code
495 * does a corresponding reconstruction of an argument vector from the
496 * command line, to be passed to main(). Complications arise when you have
497 * argument vector elements that contain spaces of double quotes. The
498 * <function>spawn*()</function> functions don't do any quoting or
499 * escaping, but on the other hand the startup code does do unquoting
500 * and unescaping in order to enable receiving arguments with embedded
501 * spaces or double quotes. To work around this asymmetry,
502 * g_spawn_async_with_pipes() will do quoting and escaping on argument
503 * vector elements that need it before calling the C runtime
506 * The returned @child_pid on Windows is a handle to the child
507 * process, not its identifier. Process handles and process
508 * identifiers are different concepts on Windows.
510 * @envp is a %NULL-terminated array of strings, where each string
511 * has the form <literal>KEY=VALUE</literal>. This will become
512 * the child's environment. If @envp is %NULL, the child inherits its
513 * parent's environment.
515 * @flags should be the bitwise OR of any flags you want to affect the
516 * function's behaviour. The %G_SPAWN_DO_NOT_REAP_CHILD means that
517 * the child will not automatically be reaped; you must use a
518 * #GChildWatch source to be notified about the death of the child
519 * process. Eventually you must call g_spawn_close_pid() on the
520 * @child_pid, in order to free resources which may be associated
521 * with the child process. (On Unix, using a #GChildWatch source is
522 * equivalent to calling waitpid() or handling the %SIGCHLD signal
523 * manually. On Windows, calling g_spawn_close_pid() is equivalent
524 * to calling CloseHandle() on the process handle returned in
527 * %G_SPAWN_LEAVE_DESCRIPTORS_OPEN means that the parent's open file
528 * descriptors will be inherited by the child; otherwise all
529 * descriptors except stdin/stdout/stderr will be closed before
530 * calling exec() in the child. %G_SPAWN_SEARCH_PATH
531 * means that <literal>argv[0]</literal> need not be an absolute path, it
532 * will be looked for in the user's <envar>PATH</envar>.
533 * %G_SPAWN_STDOUT_TO_DEV_NULL means that the child's standard output will
534 * be discarded, instead of going to the same location as the parent's
535 * standard output. If you use this flag, @standard_output must be %NULL.
536 * %G_SPAWN_STDERR_TO_DEV_NULL means that the child's standard error
537 * will be discarded, instead of going to the same location as the parent's
538 * standard error. If you use this flag, @standard_error must be %NULL.
539 * %G_SPAWN_CHILD_INHERITS_STDIN means that the child will inherit the parent's
540 * standard input (by default, the child's standard input is attached to
541 * /dev/null). If you use this flag, @standard_input must be %NULL.
542 * %G_SPAWN_FILE_AND_ARGV_ZERO means that the first element of @argv is
543 * the file to execute, while the remaining elements are the
544 * actual argument vector to pass to the file. Normally
545 * g_spawn_async_with_pipes() uses @argv[0] as the file to execute, and
546 * passes all of @argv to the child.
548 * @child_setup and @user_data are a function and user data. On POSIX
549 * platforms, the function is called in the child after GLib has
550 * performed all the setup it plans to perform (including creating
551 * pipes, closing file descriptors, etc.) but before calling
552 * exec(). That is, @child_setup is called just
553 * before calling exec() in the child. Obviously
554 * actions taken in this function will only affect the child, not the
557 * On Windows, there is no separate fork() and exec()
558 * functionality. Child processes are created and run with a single
559 * API call, CreateProcess(). There is no sensible thing @child_setup
560 * could be used for on Windows so it is ignored and not called.
562 * If non-%NULL, @child_pid will on Unix be filled with the child's
563 * process ID. You can use the process ID to send signals to the
564 * child, or to use g_child_watch_add() (or waitpid()) if you specified the
565 * %G_SPAWN_DO_NOT_REAP_CHILD flag. On Windows, @child_pid will be
566 * filled with a handle to the child process only if you specified the
567 * %G_SPAWN_DO_NOT_REAP_CHILD flag. You can then access the child
568 * process using the Win32 API, for example wait for its termination
569 * with the <function>WaitFor*()</function> functions, or examine its
570 * exit code with GetExitCodeProcess(). You should close the handle
571 * with CloseHandle() or g_spawn_close_pid() when you no longer need it.
573 * If non-%NULL, the @standard_input, @standard_output, @standard_error
574 * locations will be filled with file descriptors for writing to the child's
575 * standard input or reading from its standard output or standard error.
576 * The caller of g_spawn_async_with_pipes() must close these file descriptors
577 * when they are no longer in use. If these parameters are %NULL, the corresponding
578 * pipe won't be created.
580 * If @standard_input is NULL, the child's standard input is attached to
581 * /dev/null unless %G_SPAWN_CHILD_INHERITS_STDIN is set.
583 * If @standard_error is NULL, the child's standard error goes to the same
584 * location as the parent's standard error unless %G_SPAWN_STDERR_TO_DEV_NULL
587 * If @standard_output is NULL, the child's standard output goes to the same
588 * location as the parent's standard output unless %G_SPAWN_STDOUT_TO_DEV_NULL
591 * @error can be %NULL to ignore errors, or non-%NULL to report errors.
592 * If an error is set, the function returns %FALSE. Errors
593 * are reported even if they occur in the child (for example if the
594 * executable in <literal>argv[0]</literal> is not found). Typically
595 * the <literal>message</literal> field of returned errors should be displayed
596 * to users. Possible errors are those from the #G_SPAWN_ERROR domain.
598 * If an error occurs, @child_pid, @standard_input, @standard_output,
599 * and @standard_error will not be filled with valid values.
601 * If @child_pid is not %NULL and an error does not occur then the returned
602 * process reference must be closed using g_spawn_close_pid().
605 * If you are writing a GTK+ application, and the program you
606 * are spawning is a graphical application, too, then you may
607 * want to use gdk_spawn_on_screen_with_pipes() instead to ensure that
608 * the spawned program opens its windows on the right screen.
611 * Return value: %TRUE on success, %FALSE if an error was set
614 g_spawn_async_with_pipes (const gchar *working_directory,
618 GSpawnChildSetupFunc child_setup,
621 gint *standard_input,
622 gint *standard_output,
623 gint *standard_error,
626 g_return_val_if_fail (argv != NULL, FALSE);
627 g_return_val_if_fail (standard_output == NULL ||
628 !(flags & G_SPAWN_STDOUT_TO_DEV_NULL), FALSE);
629 g_return_val_if_fail (standard_error == NULL ||
630 !(flags & G_SPAWN_STDERR_TO_DEV_NULL), FALSE);
631 /* can't inherit stdin if we have an input pipe. */
632 g_return_val_if_fail (standard_input == NULL ||
633 !(flags & G_SPAWN_CHILD_INHERITS_STDIN), FALSE);
635 return fork_exec_with_pipes (!(flags & G_SPAWN_DO_NOT_REAP_CHILD),
639 !(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN),
640 (flags & G_SPAWN_SEARCH_PATH) != 0,
641 (flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0,
642 (flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0,
643 (flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0,
644 (flags & G_SPAWN_FILE_AND_ARGV_ZERO) != 0,
655 * g_spawn_command_line_sync:
656 * @command_line: a command line
657 * @standard_output: return location for child output
658 * @standard_error: return location for child errors
659 * @exit_status: return location for child exit status, as returned by waitpid()
660 * @error: return location for errors
662 * A simple version of g_spawn_sync() with little-used parameters
663 * removed, taking a command line instead of an argument vector. See
664 * g_spawn_sync() for full details. @command_line will be parsed by
665 * g_shell_parse_argv(). Unlike g_spawn_sync(), the %G_SPAWN_SEARCH_PATH flag
666 * is enabled. Note that %G_SPAWN_SEARCH_PATH can have security
667 * implications, so consider using g_spawn_sync() directly if
668 * appropriate. Possible errors are those from g_spawn_sync() and those
669 * from g_shell_parse_argv().
671 * If @exit_status is non-%NULL, the exit status of the child is stored there as
672 * it would be returned by waitpid(); standard UNIX macros such as WIFEXITED()
673 * and WEXITSTATUS() must be used to evaluate the exit status.
675 * On Windows, please note the implications of g_shell_parse_argv()
676 * parsing @command_line. Parsing is done according to Unix shell rules, not
677 * Windows command interpreter rules.
678 * Space is a separator, and backslashes are
679 * special. Thus you cannot simply pass a @command_line containing
680 * canonical Windows paths, like "c:\\program files\\app\\app.exe", as
681 * the backslashes will be eaten, and the space will act as a
682 * separator. You need to enclose such paths with single quotes, like
683 * "'c:\\program files\\app\\app.exe' 'e:\\folder\\argument.txt'".
685 * Return value: %TRUE on success, %FALSE if an error was set
688 g_spawn_command_line_sync (const gchar *command_line,
689 gchar **standard_output,
690 gchar **standard_error,
697 g_return_val_if_fail (command_line != NULL, FALSE);
699 if (!g_shell_parse_argv (command_line,
704 retval = g_spawn_sync (NULL,
720 * g_spawn_command_line_async:
721 * @command_line: a command line
722 * @error: return location for errors
724 * A simple version of g_spawn_async() that parses a command line with
725 * g_shell_parse_argv() and passes it to g_spawn_async(). Runs a
726 * command line in the background. Unlike g_spawn_async(), the
727 * %G_SPAWN_SEARCH_PATH flag is enabled, other flags are not. Note
728 * that %G_SPAWN_SEARCH_PATH can have security implications, so
729 * consider using g_spawn_async() directly if appropriate. Possible
730 * errors are those from g_shell_parse_argv() and g_spawn_async().
732 * The same concerns on Windows apply as for g_spawn_command_line_sync().
734 * Return value: %TRUE on success, %FALSE if error is set.
737 g_spawn_command_line_async (const gchar *command_line,
743 g_return_val_if_fail (command_line != NULL, FALSE);
745 if (!g_shell_parse_argv (command_line,
750 retval = g_spawn_async (NULL,
764 exec_err_to_g_error (gint en)
770 return G_SPAWN_ERROR_ACCES;
776 return G_SPAWN_ERROR_PERM;
782 return G_SPAWN_ERROR_2BIG;
788 return G_SPAWN_ERROR_NOEXEC;
794 return G_SPAWN_ERROR_NAMETOOLONG;
800 return G_SPAWN_ERROR_NOENT;
806 return G_SPAWN_ERROR_NOMEM;
812 return G_SPAWN_ERROR_NOTDIR;
818 return G_SPAWN_ERROR_LOOP;
824 return G_SPAWN_ERROR_TXTBUSY;
830 return G_SPAWN_ERROR_IO;
836 return G_SPAWN_ERROR_NFILE;
842 return G_SPAWN_ERROR_MFILE;
848 return G_SPAWN_ERROR_INVAL;
854 return G_SPAWN_ERROR_ISDIR;
860 return G_SPAWN_ERROR_LIBBAD;
865 return G_SPAWN_ERROR_FAILED;
871 write_all (gint fd, gconstpointer vbuf, gsize to_write)
873 gchar *buf = (gchar *) vbuf;
877 gssize count = write (fd, buf, to_write);
895 write_err_and_exit (gint fd, gint msg)
899 write_all (fd, &msg, sizeof(msg));
900 write_all (fd, &en, sizeof(en));
906 set_cloexec (void *data, gint fd)
908 if (fd >= GPOINTER_TO_INT (data))
909 fcntl (fd, F_SETFD, FD_CLOEXEC);
916 fdwalk (int (*cb)(void *data, int fd), void *data)
922 #ifdef HAVE_SYS_RESOURCE_H
929 if ((d = opendir("/proc/self/fd"))) {
932 while ((de = readdir(d))) {
936 if (de->d_name[0] == '.')
940 l = strtol(de->d_name, &e, 10);
941 if (errno != 0 || !e || *e)
952 if ((res = cb (data, fd)) != 0)
960 /* If /proc is not mounted or not accessible we fall back to the old
965 #ifdef HAVE_SYS_RESOURCE_H
967 if (getrlimit(RLIMIT_NOFILE, &rl) == 0 && rl.rlim_max != RLIM_INFINITY)
968 open_max = rl.rlim_max;
971 open_max = sysconf (_SC_OPEN_MAX);
973 for (fd = 0; fd < open_max; fd++)
974 if ((res = cb (data, fd)) != 0)
982 sane_dup2 (gint fd1, gint fd2)
987 ret = dup2 (fd1, fd2);
988 if (ret < 0 && errno == EINTR)
1003 do_exec (gint child_err_report_fd,
1007 const gchar *working_directory,
1010 gboolean close_descriptors,
1011 gboolean search_path,
1012 gboolean stdout_to_null,
1013 gboolean stderr_to_null,
1014 gboolean child_inherits_stdin,
1015 gboolean file_and_argv_zero,
1016 GSpawnChildSetupFunc child_setup,
1019 if (working_directory && chdir (working_directory) < 0)
1020 write_err_and_exit (child_err_report_fd,
1021 CHILD_CHDIR_FAILED);
1023 /* Close all file descriptors but stdin stdout and stderr as
1024 * soon as we exec. Note that this includes
1025 * child_err_report_fd, which keeps the parent from blocking
1026 * forever on the other end of that pipe.
1028 if (close_descriptors)
1030 fdwalk (set_cloexec, GINT_TO_POINTER(3));
1034 /* We need to do child_err_report_fd anyway */
1035 set_cloexec (GINT_TO_POINTER(0), child_err_report_fd);
1038 /* Redirect pipes as required */
1042 /* dup2 can't actually fail here I don't think */
1044 if (sane_dup2 (stdin_fd, 0) < 0)
1045 write_err_and_exit (child_err_report_fd,
1048 /* ignore this if it doesn't work */
1049 close_and_invalidate (&stdin_fd);
1051 else if (!child_inherits_stdin)
1053 /* Keep process from blocking on a read of stdin */
1054 gint read_null = open ("/dev/null", O_RDONLY);
1055 sane_dup2 (read_null, 0);
1056 close_and_invalidate (&read_null);
1061 /* dup2 can't actually fail here I don't think */
1063 if (sane_dup2 (stdout_fd, 1) < 0)
1064 write_err_and_exit (child_err_report_fd,
1067 /* ignore this if it doesn't work */
1068 close_and_invalidate (&stdout_fd);
1070 else if (stdout_to_null)
1072 gint write_null = open ("/dev/null", O_WRONLY);
1073 sane_dup2 (write_null, 1);
1074 close_and_invalidate (&write_null);
1079 /* dup2 can't actually fail here I don't think */
1081 if (sane_dup2 (stderr_fd, 2) < 0)
1082 write_err_and_exit (child_err_report_fd,
1085 /* ignore this if it doesn't work */
1086 close_and_invalidate (&stderr_fd);
1088 else if (stderr_to_null)
1090 gint write_null = open ("/dev/null", O_WRONLY);
1091 sane_dup2 (write_null, 2);
1092 close_and_invalidate (&write_null);
1095 /* Call user function just before we exec */
1098 (* child_setup) (user_data);
1102 file_and_argv_zero ? argv + 1 : argv,
1106 write_err_and_exit (child_err_report_fd,
1123 if (bytes >= sizeof(gint)*2)
1124 break; /* give up, who knows what happened, should not be
1130 ((gchar*)buf) + bytes,
1131 sizeof(gint) * n_ints_in_buf - bytes);
1132 if (chunk < 0 && errno == EINTR)
1139 /* Some weird shit happened, bail out */
1142 G_SPAWN_ERROR_FAILED,
1143 _("Failed to read from child pipe (%s)"),
1144 g_strerror (errsv));
1148 else if (chunk == 0)
1150 else /* chunk > 0 */
1154 *n_ints_read = (gint)(bytes / sizeof(gint));
1160 fork_exec_with_pipes (gboolean intermediate_child,
1161 const gchar *working_directory,
1164 gboolean close_descriptors,
1165 gboolean search_path,
1166 gboolean stdout_to_null,
1167 gboolean stderr_to_null,
1168 gboolean child_inherits_stdin,
1169 gboolean file_and_argv_zero,
1170 GSpawnChildSetupFunc child_setup,
1173 gint *standard_input,
1174 gint *standard_output,
1175 gint *standard_error,
1179 gint stdin_pipe[2] = { -1, -1 };
1180 gint stdout_pipe[2] = { -1, -1 };
1181 gint stderr_pipe[2] = { -1, -1 };
1182 gint child_err_report_pipe[2] = { -1, -1 };
1183 gint child_pid_report_pipe[2] = { -1, -1 };
1186 if (!make_pipe (child_err_report_pipe, error))
1189 if (intermediate_child && !make_pipe (child_pid_report_pipe, error))
1190 goto cleanup_and_fail;
1192 if (standard_input && !make_pipe (stdin_pipe, error))
1193 goto cleanup_and_fail;
1195 if (standard_output && !make_pipe (stdout_pipe, error))
1196 goto cleanup_and_fail;
1198 if (standard_error && !make_pipe (stderr_pipe, error))
1199 goto cleanup_and_fail;
1210 _("Failed to fork (%s)"),
1211 g_strerror (errsv));
1213 goto cleanup_and_fail;
1217 /* Immediate child. This may or may not be the child that
1218 * actually execs the new process.
1221 /* Be sure we crash if the parent exits
1222 * and we write to the err_report_pipe
1224 signal (SIGPIPE, SIG_DFL);
1226 /* Close the parent's end of the pipes;
1227 * not needed in the close_descriptors case,
1230 close_and_invalidate (&child_err_report_pipe[0]);
1231 close_and_invalidate (&child_pid_report_pipe[0]);
1232 close_and_invalidate (&stdin_pipe[1]);
1233 close_and_invalidate (&stdout_pipe[0]);
1234 close_and_invalidate (&stderr_pipe[0]);
1236 if (intermediate_child)
1238 /* We need to fork an intermediate child that launches the
1239 * final child. The purpose of the intermediate child
1240 * is to exit, so we can waitpid() it immediately.
1241 * Then the grandchild will not become a zombie.
1243 GPid grandchild_pid;
1245 grandchild_pid = fork ();
1247 if (grandchild_pid < 0)
1249 /* report -1 as child PID */
1250 write_all (child_pid_report_pipe[1], &grandchild_pid,
1251 sizeof(grandchild_pid));
1253 write_err_and_exit (child_err_report_pipe[1],
1256 else if (grandchild_pid == 0)
1258 do_exec (child_err_report_pipe[1],
1269 child_inherits_stdin,
1276 write_all (child_pid_report_pipe[1], &grandchild_pid, sizeof(grandchild_pid));
1277 close_and_invalidate (&child_pid_report_pipe[1]);
1284 /* Just run the child.
1287 do_exec (child_err_report_pipe[1],
1298 child_inherits_stdin,
1311 /* Close the uncared-about ends of the pipes */
1312 close_and_invalidate (&child_err_report_pipe[1]);
1313 close_and_invalidate (&child_pid_report_pipe[1]);
1314 close_and_invalidate (&stdin_pipe[0]);
1315 close_and_invalidate (&stdout_pipe[1]);
1316 close_and_invalidate (&stderr_pipe[1]);
1318 /* If we had an intermediate child, reap it */
1319 if (intermediate_child)
1322 if (waitpid (pid, &status, 0) < 0)
1326 else if (errno == ECHILD)
1327 ; /* do nothing, child already reaped */
1329 g_warning ("waitpid() should not fail in "
1330 "'fork_exec_with_pipes'");
1335 if (!read_ints (child_err_report_pipe[0],
1338 goto cleanup_and_fail;
1342 /* Error from the child. */
1346 case CHILD_CHDIR_FAILED:
1349 G_SPAWN_ERROR_CHDIR,
1350 _("Failed to change to directory '%s' (%s)"),
1352 g_strerror (buf[1]));
1356 case CHILD_EXEC_FAILED:
1359 exec_err_to_g_error (buf[1]),
1360 _("Failed to execute child process \"%s\" (%s)"),
1362 g_strerror (buf[1]));
1366 case CHILD_DUP2_FAILED:
1369 G_SPAWN_ERROR_FAILED,
1370 _("Failed to redirect output or input of child process (%s)"),
1371 g_strerror (buf[1]));
1375 case CHILD_FORK_FAILED:
1379 _("Failed to fork child process (%s)"),
1380 g_strerror (buf[1]));
1386 G_SPAWN_ERROR_FAILED,
1387 _("Unknown error executing child process \"%s\""),
1392 goto cleanup_and_fail;
1395 /* Get child pid from intermediate child pipe. */
1396 if (intermediate_child)
1400 if (!read_ints (child_pid_report_pipe[0],
1401 buf, 1, &n_ints, error))
1402 goto cleanup_and_fail;
1410 G_SPAWN_ERROR_FAILED,
1411 _("Failed to read enough data from child pid pipe (%s)"),
1412 g_strerror (errsv));
1413 goto cleanup_and_fail;
1417 /* we have the child pid */
1422 /* Success against all odds! return the information */
1423 close_and_invalidate (&child_err_report_pipe[0]);
1424 close_and_invalidate (&child_pid_report_pipe[0]);
1430 *standard_input = stdin_pipe[1];
1431 if (standard_output)
1432 *standard_output = stdout_pipe[0];
1434 *standard_error = stderr_pipe[0];
1441 /* There was an error from the Child, reap the child to avoid it being
1448 if (waitpid (pid, NULL, 0) < 0)
1452 else if (errno == ECHILD)
1453 ; /* do nothing, child already reaped */
1455 g_warning ("waitpid() should not fail in "
1456 "'fork_exec_with_pipes'");
1460 close_and_invalidate (&child_err_report_pipe[0]);
1461 close_and_invalidate (&child_err_report_pipe[1]);
1462 close_and_invalidate (&child_pid_report_pipe[0]);
1463 close_and_invalidate (&child_pid_report_pipe[1]);
1464 close_and_invalidate (&stdin_pipe[0]);
1465 close_and_invalidate (&stdin_pipe[1]);
1466 close_and_invalidate (&stdout_pipe[0]);
1467 close_and_invalidate (&stdout_pipe[1]);
1468 close_and_invalidate (&stderr_pipe[0]);
1469 close_and_invalidate (&stderr_pipe[1]);
1475 make_pipe (gint p[2],
1483 G_SPAWN_ERROR_FAILED,
1484 _("Failed to create pipe for communicating with child process (%s)"),
1485 g_strerror (errsv));
1492 /* Based on execvp from GNU C Library */
1495 script_execute (const gchar *file,
1498 gboolean search_path)
1500 /* Count the arguments. */
1505 /* Construct an argument list for the shell. */
1509 new_argv = g_new0 (gchar*, argc + 2); /* /bin/sh and NULL */
1511 new_argv[0] = (char *) "/bin/sh";
1512 new_argv[1] = (char *) file;
1515 new_argv[argc + 1] = argv[argc];
1519 /* Execute the shell. */
1521 execve (new_argv[0], new_argv, envp);
1523 execv (new_argv[0], new_argv);
1530 my_strchrnul (const gchar *str, gchar c)
1532 gchar *p = (gchar*) str;
1533 while (*p && (*p != c))
1540 g_execute (const gchar *file,
1543 gboolean search_path)
1547 /* We check the simple case first. */
1552 if (!search_path || strchr (file, '/') != NULL)
1554 /* Don't search when it contains a slash. */
1556 execve (file, argv, envp);
1560 if (errno == ENOEXEC)
1561 script_execute (file, argv, envp, FALSE);
1565 gboolean got_eacces = 0;
1566 const gchar *path, *p;
1567 gchar *name, *freeme;
1571 path = g_getenv ("PATH");
1574 /* There is no `PATH' in the environment. The default
1575 * search path in libc is the current directory followed by
1576 * the path `confstr' returns for `_CS_PATH'.
1579 /* In GLib we put . last, for security, and don't use the
1580 * unportable confstr(); UNIX98 does not actually specify
1581 * what to search if PATH is unset. POSIX may, dunno.
1584 path = "/bin:/usr/bin:.";
1587 len = strlen (file) + 1;
1588 pathlen = strlen (path);
1589 freeme = name = g_malloc (pathlen + len + 1);
1591 /* Copy the file name at the top, including '\0' */
1592 memcpy (name + pathlen + 1, file, len);
1593 name = name + pathlen;
1594 /* And add the slash before the filename */
1603 p = my_strchrnul (path, ':');
1606 /* Two adjacent colons, or a colon at the beginning or the end
1607 * of `PATH' means to search the current directory.
1611 startp = memcpy (name - (p - path), path, p - path);
1613 /* Try to execute this name. If it works, execv will not return. */
1615 execve (startp, argv, envp);
1617 execv (startp, argv);
1619 if (errno == ENOEXEC)
1620 script_execute (startp, argv, envp, search_path);
1625 /* Record the we got a `Permission denied' error. If we end
1626 * up finding no executable we can use, we want to diagnose
1627 * that we did find one but were denied access.
1640 /* Those errors indicate the file is missing or not executable
1641 * by us, in which case we want to just try the next path
1647 /* Some other error means we found an executable file, but
1648 * something went wrong executing it; return the error to our
1655 while (*p++ != '\0');
1657 /* We tried every element and none of them worked. */
1659 /* At least one failure was due to permissions, so report that
1667 /* Return the error from the last attempt (probably ENOENT). */
1672 * g_spawn_close_pid:
1673 * @pid: The process reference to close
1675 * On some platforms, notably Windows, the #GPid type represents a resource
1676 * which must be closed to prevent resource leaking. g_spawn_close_pid()
1677 * is provided for this purpose. It should be used on all platforms, even
1678 * though it doesn't do anything under UNIX.
1681 g_spawn_close_pid (GPid pid)