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 static gint g_execute (const gchar *file,
51 gboolean search_path);
53 static gboolean make_pipe (gint p[2],
55 static gboolean fork_exec_with_pipes (gboolean intermediate_child,
56 const gchar *working_directory,
59 gboolean close_descriptors,
61 gboolean stdout_to_null,
62 gboolean stderr_to_null,
63 gboolean child_inherits_stdin,
64 gboolean file_and_argv_zero,
65 GSpawnChildSetupFunc child_setup,
69 gint *standard_output,
74 g_spawn_error_quark (void)
76 return g_quark_from_static_string ("g-exec-error-quark");
81 * @working_directory: child's current working directory, or %NULL to inherit parent's
82 * @argv: child's argument vector
83 * @envp: child's environment, or %NULL to inherit parent's
84 * @flags: flags from #GSpawnFlags
85 * @child_setup: function to run in the child just before exec()
86 * @user_data: user data for @child_setup
87 * @child_pid: return location for child process ID, or %NULL
88 * @error: return location for error
90 * See g_spawn_async_with_pipes() for a full description; this function
91 * simply calls the g_spawn_async_with_pipes() without any pipes.
94 * If you are writing a GTK+ application, and the program you
95 * are spawning is a graphical application, too, then you may
96 * want to use gdk_spawn_on_screen() instead to ensure that
97 * the spawned program opens its windows on the right screen.
100 * Return value: %TRUE on success, %FALSE if error is set
103 g_spawn_async (const gchar *working_directory,
107 GSpawnChildSetupFunc child_setup,
112 g_return_val_if_fail (argv != NULL, FALSE);
114 return g_spawn_async_with_pipes (working_directory,
124 /* Avoids a danger in threaded situations (calling close()
125 * on a file descriptor twice, and another thread has
126 * re-opened it since the first close)
129 close_and_invalidate (gint *fd)
144 /* Some versions of OS X define READ_OK in public headers */
149 READ_FAILED = 0, /* FALSE */
155 read_data (GString *str,
164 bytes = read (fd, buf, 4096);
170 g_string_append_len (str, buf, bytes);
173 else if (bytes < 0 && errno == EINTR)
180 _("Failed to read data from child process (%s)"),
191 * @working_directory: child's current working directory, or %NULL to inherit parent's
192 * @argv: child's argument vector
193 * @envp: child's environment, or %NULL to inherit parent's
194 * @flags: flags from #GSpawnFlags
195 * @child_setup: function to run in the child just before exec()
196 * @user_data: user data for @child_setup
197 * @standard_output: return location for child output, or %NULL
198 * @standard_error: return location for child error messages, or %NULL
199 * @exit_status: return location for child exit status, as returned by waitpid(), or %NULL
200 * @error: return location for error, or %NULL
202 * Executes a child synchronously (waits for the child to exit before returning).
203 * All output from the child is stored in @standard_output and @standard_error,
204 * if those parameters are non-%NULL. Note that you must set the
205 * %G_SPAWN_STDOUT_TO_DEV_NULL and %G_SPAWN_STDERR_TO_DEV_NULL flags when
206 * passing %NULL for @standard_output and @standard_error.
207 * If @exit_status is non-%NULL, the exit status of the child is stored
208 * there as it would be returned by waitpid(); standard UNIX macros such
209 * as WIFEXITED() and WEXITSTATUS() must be used to evaluate the exit status.
210 * Note that this function call waitpid() even if @exit_status is %NULL, and
211 * does not accept the %G_SPAWN_DO_NOT_REAP_CHILD flag.
212 * If an error occurs, no data is returned in @standard_output,
213 * @standard_error, or @exit_status.
215 * This function calls g_spawn_async_with_pipes() internally; see that
216 * function for full details on the other parameters and details on
217 * how these functions work on Windows.
219 * Return value: %TRUE on success, %FALSE if an error was set.
222 g_spawn_sync (const gchar *working_directory,
226 GSpawnChildSetupFunc child_setup,
228 gchar **standard_output,
229 gchar **standard_error,
238 GString *outstr = NULL;
239 GString *errstr = NULL;
243 g_return_val_if_fail (argv != NULL, FALSE);
244 g_return_val_if_fail (!(flags & G_SPAWN_DO_NOT_REAP_CHILD), FALSE);
245 g_return_val_if_fail (standard_output == NULL ||
246 !(flags & G_SPAWN_STDOUT_TO_DEV_NULL), FALSE);
247 g_return_val_if_fail (standard_error == NULL ||
248 !(flags & G_SPAWN_STDERR_TO_DEV_NULL), FALSE);
250 /* Just to ensure segfaults if callers try to use
251 * these when an error is reported.
254 *standard_output = NULL;
257 *standard_error = NULL;
259 if (!fork_exec_with_pipes (FALSE,
263 !(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN),
264 (flags & G_SPAWN_SEARCH_PATH) != 0,
265 (flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0,
266 (flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0,
267 (flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0,
268 (flags & G_SPAWN_FILE_AND_ARGV_ZERO) != 0,
273 standard_output ? &outpipe : NULL,
274 standard_error ? &errpipe : NULL,
278 /* Read data from child. */
284 outstr = g_string_new (NULL);
289 errstr = g_string_new (NULL);
292 /* Read data until we get EOF on both pipes. */
301 FD_SET (outpipe, &fds);
303 FD_SET (errpipe, &fds);
305 ret = select (MAX (outpipe, errpipe) + 1,
308 NULL /* no timeout */);
310 if (ret < 0 && errno != EINTR)
317 _("Unexpected error in select() reading data from a child process (%s)"),
323 if (outpipe >= 0 && FD_ISSET (outpipe, &fds))
325 switch (read_data (outstr, outpipe, error))
331 close_and_invalidate (&outpipe);
342 if (errpipe >= 0 && FD_ISSET (errpipe, &fds))
344 switch (read_data (errstr, errpipe, error))
350 close_and_invalidate (&errpipe);
362 /* These should only be open still if we had an error. */
365 close_and_invalidate (&outpipe);
367 close_and_invalidate (&errpipe);
369 /* Wait for child to exit, even if we have
374 ret = waitpid (pid, &status, 0);
380 else if (errno == ECHILD)
384 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.");
388 /* We don't need the exit status. */
393 if (!failed) /* avoid error pileups */
400 _("Unexpected error in waitpid() (%s)"),
409 g_string_free (outstr, TRUE);
411 g_string_free (errstr, TRUE);
418 *exit_status = status;
421 *standard_output = g_string_free (outstr, FALSE);
424 *standard_error = g_string_free (errstr, FALSE);
431 * g_spawn_async_with_pipes:
432 * @working_directory: child's current working directory, or %NULL to inherit parent's, in the GLib file name encoding
433 * @argv: child's argument vector, in the GLib file name encoding
434 * @envp: child's environment, or %NULL to inherit parent's, in the GLib file name encoding
435 * @flags: flags from #GSpawnFlags
436 * @child_setup: function to run in the child just before exec()
437 * @user_data: user data for @child_setup
438 * @child_pid: return location for child process ID, or %NULL
439 * @standard_input: return location for file descriptor to write to child's stdin, or %NULL
440 * @standard_output: return location for file descriptor to read child's stdout, or %NULL
441 * @standard_error: return location for file descriptor to read child's stderr, or %NULL
442 * @error: return location for error
444 * Executes a child program asynchronously (your program will not
445 * block waiting for the child to exit). The child program is
446 * specified by the only argument that must be provided, @argv. @argv
447 * should be a %NULL-terminated array of strings, to be passed as the
448 * argument vector for the child. The first string in @argv is of
449 * course the name of the program to execute. By default, the name of
450 * the program must be a full path; the <envar>PATH</envar> shell variable
451 * will only be searched if you pass the %G_SPAWN_SEARCH_PATH flag.
453 * On Windows, note that all the string or string vector arguments to
454 * this function and the other g_spawn*() functions are in UTF-8, the
455 * GLib file name encoding. Unicode characters that are not part of
456 * the system codepage passed in these arguments will be correctly
457 * available in the spawned program only if it uses wide character API
458 * to retrieve its command line. For C programs built with Microsoft's
459 * tools it is enough to make the program have a wmain() instead of
460 * main(). wmain() has a wide character argument vector as parameter.
462 * At least currently, mingw doesn't support wmain(), so if you use
463 * mingw to develop the spawned program, it will have to call the
464 * undocumented function __wgetmainargs() to get the wide character
465 * argument vector and environment. See gspawn-win32-helper.c in the
466 * GLib sources or init.c in the mingw runtime sources for a prototype
467 * for that function. Alternatively, you can retrieve the Win32 system
468 * level wide character command line passed to the spawned program
469 * using the GetCommandLineW() function.
471 * On Windows the low-level child process creation API
472 * <function>CreateProcess()</function> doesn't use argument vectors,
473 * but a command line. The C runtime library's
474 * <function>spawn*()</function> family of functions (which
475 * g_spawn_async_with_pipes() eventually calls) paste the argument
476 * vector elements together into a command line, and the C runtime startup code
477 * does a corresponding reconstruction of an argument vector from the
478 * command line, to be passed to main(). Complications arise when you have
479 * argument vector elements that contain spaces of double quotes. The
480 * <function>spawn*()</function> functions don't do any quoting or
481 * escaping, but on the other hand the startup code does do unquoting
482 * and unescaping in order to enable receiving arguments with embedded
483 * spaces or double quotes. To work around this asymmetry,
484 * g_spawn_async_with_pipes() will do quoting and escaping on argument
485 * vector elements that need it before calling the C runtime
488 * @envp is a %NULL-terminated array of strings, where each string
489 * has the form <literal>KEY=VALUE</literal>. This will become
490 * the child's environment. If @envp is %NULL, the child inherits its
491 * parent's environment.
493 * @flags should be the bitwise OR of any flags you want to affect the
494 * function's behaviour. The %G_SPAWN_DO_NOT_REAP_CHILD means that
495 * the child will not automatically be reaped; you must use a
496 * #GChildWatch source to be notified about the death of the child
497 * process. Eventually you must call g_spawn_close_pid() on the
498 * @child_pid, in order to free resources which may be associated
499 * with the child process. (On Unix, using a #GChildWatch source is
500 * equivalent to calling waitpid() or handling the %SIGCHLD signal
501 * manually. On Windows, calling g_spawn_close_pid() is equivalent
502 * to calling CloseHandle() on the process handle returned in
505 * %G_SPAWN_LEAVE_DESCRIPTORS_OPEN means that the parent's open file
506 * descriptors will be inherited by the child; otherwise all
507 * descriptors except stdin/stdout/stderr will be closed before
508 * calling exec() in the child. %G_SPAWN_SEARCH_PATH
509 * means that <literal>argv[0]</literal> need not be an absolute path, it
510 * will be looked for in the user's <envar>PATH</envar>.
511 * %G_SPAWN_STDOUT_TO_DEV_NULL means that the child's standard output will
512 * be discarded, instead of going to the same location as the parent's
513 * standard output. If you use this flag, @standard_output must be %NULL.
514 * %G_SPAWN_STDERR_TO_DEV_NULL means that the child's standard error
515 * will be discarded, instead of going to the same location as the parent's
516 * standard error. If you use this flag, @standard_error must be %NULL.
517 * %G_SPAWN_CHILD_INHERITS_STDIN means that the child will inherit the parent's
518 * standard input (by default, the child's standard input is attached to
519 * /dev/null). If you use this flag, @standard_input must be %NULL.
520 * %G_SPAWN_FILE_AND_ARGV_ZERO means that the first element of @argv is
521 * the file to execute, while the remaining elements are the
522 * actual argument vector to pass to the file. Normally
523 * g_spawn_async_with_pipes() uses @argv[0] as the file to execute, and
524 * passes all of @argv to the child.
526 * @child_setup and @user_data are a function and user data. On POSIX
527 * platforms, the function is called in the child after GLib has
528 * performed all the setup it plans to perform (including creating
529 * pipes, closing file descriptors, etc.) but before calling
530 * exec(). That is, @child_setup is called just
531 * before calling exec() in the child. Obviously
532 * actions taken in this function will only affect the child, not the
533 * parent. On Windows, there is no separate fork() and exec()
534 * functionality. Child processes are created and run with
535 * a single API call, CreateProcess(). @child_setup is
536 * called in the parent process just before creating the child
537 * process. You should carefully consider what you do in @child_setup
538 * if you intend your software to be portable to Windows.
540 * If non-%NULL, @child_pid will on Unix be filled with the child's
541 * process ID. You can use the process ID to send signals to the
542 * child, or to use g_child_watch_add() (or waitpid()) if you specified the
543 * %G_SPAWN_DO_NOT_REAP_CHILD flag. On Windows, @child_pid will be
544 * filled with a handle to the child process only if you specified the
545 * %G_SPAWN_DO_NOT_REAP_CHILD flag. You can then access the child
546 * process using the Win32 API, for example wait for its termination
547 * with the <function>WaitFor*()</function> functions, or examine its
548 * exit code with GetExitCodeProcess(). You should close the handle
549 * with CloseHandle() or g_spawn_close_pid() when you no longer need it.
551 * If non-%NULL, the @standard_input, @standard_output, @standard_error
552 * locations will be filled with file descriptors for writing to the child's
553 * standard input or reading from its standard output or standard error.
554 * The caller of g_spawn_async_with_pipes() must close these file descriptors
555 * when they are no longer in use. If these parameters are %NULL, the corresponding
556 * pipe won't be created.
558 * If @standard_input is NULL, the child's standard input is attached to
559 * /dev/null unless %G_SPAWN_CHILD_INHERITS_STDIN is set.
561 * If @standard_error is NULL, the child's standard error goes to the same
562 * location as the parent's standard error unless %G_SPAWN_STDERR_TO_DEV_NULL
565 * If @standard_output is NULL, the child's standard output goes to the same
566 * location as the parent's standard output unless %G_SPAWN_STDOUT_TO_DEV_NULL
569 * @error can be %NULL to ignore errors, or non-%NULL to report errors.
570 * If an error is set, the function returns %FALSE. Errors
571 * are reported even if they occur in the child (for example if the
572 * executable in <literal>argv[0]</literal> is not found). Typically
573 * the <literal>message</literal> field of returned errors should be displayed
574 * to users. Possible errors are those from the #G_SPAWN_ERROR domain.
576 * If an error occurs, @child_pid, @standard_input, @standard_output,
577 * and @standard_error will not be filled with valid values.
579 * If @child_pid is not %NULL and an error does not occur then the returned
580 * pid must be closed using g_spawn_close_pid().
583 * If you are writing a GTK+ application, and the program you
584 * are spawning is a graphical application, too, then you may
585 * want to use gdk_spawn_on_screen_with_pipes() instead to ensure that
586 * the spawned program opens its windows no the right screen.
589 * Return value: %TRUE on success, %FALSE if an error was set
592 g_spawn_async_with_pipes (const gchar *working_directory,
596 GSpawnChildSetupFunc child_setup,
599 gint *standard_input,
600 gint *standard_output,
601 gint *standard_error,
604 g_return_val_if_fail (argv != NULL, FALSE);
605 g_return_val_if_fail (standard_output == NULL ||
606 !(flags & G_SPAWN_STDOUT_TO_DEV_NULL), FALSE);
607 g_return_val_if_fail (standard_error == NULL ||
608 !(flags & G_SPAWN_STDERR_TO_DEV_NULL), FALSE);
609 /* can't inherit stdin if we have an input pipe. */
610 g_return_val_if_fail (standard_input == NULL ||
611 !(flags & G_SPAWN_CHILD_INHERITS_STDIN), FALSE);
613 return fork_exec_with_pipes (!(flags & G_SPAWN_DO_NOT_REAP_CHILD),
617 !(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN),
618 (flags & G_SPAWN_SEARCH_PATH) != 0,
619 (flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0,
620 (flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0,
621 (flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0,
622 (flags & G_SPAWN_FILE_AND_ARGV_ZERO) != 0,
633 * g_spawn_command_line_sync:
634 * @command_line: a command line
635 * @standard_output: return location for child output
636 * @standard_error: return location for child errors
637 * @exit_status: return location for child exit status, as returned by waitpid()
638 * @error: return location for errors
640 * A simple version of g_spawn_sync() with little-used parameters
641 * removed, taking a command line instead of an argument vector. See
642 * g_spawn_sync() for full details. @command_line will be parsed by
643 * g_shell_parse_argv(). Unlike g_spawn_sync(), the %G_SPAWN_SEARCH_PATH flag
644 * is enabled. Note that %G_SPAWN_SEARCH_PATH can have security
645 * implications, so consider using g_spawn_sync() directly if
646 * appropriate. Possible errors are those from g_spawn_sync() and those
647 * from g_shell_parse_argv().
649 * If @exit_status is non-%NULL, the exit status of the child is stored there as
650 * it would be returned by waitpid(); standard UNIX macros such as WIFEXITED()
651 * and WEXITSTATUS() must be used to evaluate the exit status.
653 * On Windows, please note the implications of g_shell_parse_argv()
654 * parsing @command_line. Parsing is done according to Unix shell rules, not
655 * Windows command interpreter rules.
656 * Space is a separator, and backslashes are
657 * special. Thus you cannot simply pass a @command_line containing
658 * canonical Windows paths, like "c:\\program files\\app\\app.exe", as
659 * the backslashes will be eaten, and the space will act as a
660 * separator. You need to enclose such paths with single quotes, like
661 * "'c:\\program files\\app\\app.exe' 'e:\\folder\\argument.txt'".
663 * Return value: %TRUE on success, %FALSE if an error was set
666 g_spawn_command_line_sync (const gchar *command_line,
667 gchar **standard_output,
668 gchar **standard_error,
675 g_return_val_if_fail (command_line != NULL, FALSE);
677 if (!g_shell_parse_argv (command_line,
682 retval = g_spawn_sync (NULL,
698 * g_spawn_command_line_async:
699 * @command_line: a command line
700 * @error: return location for errors
702 * A simple version of g_spawn_async() that parses a command line with
703 * g_shell_parse_argv() and passes it to g_spawn_async(). Runs a
704 * command line in the background. Unlike g_spawn_async(), the
705 * %G_SPAWN_SEARCH_PATH flag is enabled, other flags are not. Note
706 * that %G_SPAWN_SEARCH_PATH can have security implications, so
707 * consider using g_spawn_async() directly if appropriate. Possible
708 * errors are those from g_shell_parse_argv() and g_spawn_async().
710 * The same concerns on Windows apply as for g_spawn_command_line_sync().
712 * Return value: %TRUE on success, %FALSE if error is set.
715 g_spawn_command_line_async (const gchar *command_line,
721 g_return_val_if_fail (command_line != NULL, FALSE);
723 if (!g_shell_parse_argv (command_line,
728 retval = g_spawn_async (NULL,
742 exec_err_to_g_error (gint en)
748 return G_SPAWN_ERROR_ACCES;
754 return G_SPAWN_ERROR_PERM;
760 return G_SPAWN_ERROR_2BIG;
766 return G_SPAWN_ERROR_NOEXEC;
772 return G_SPAWN_ERROR_NAMETOOLONG;
778 return G_SPAWN_ERROR_NOENT;
784 return G_SPAWN_ERROR_NOMEM;
790 return G_SPAWN_ERROR_NOTDIR;
796 return G_SPAWN_ERROR_LOOP;
802 return G_SPAWN_ERROR_TXTBUSY;
808 return G_SPAWN_ERROR_IO;
814 return G_SPAWN_ERROR_NFILE;
820 return G_SPAWN_ERROR_MFILE;
826 return G_SPAWN_ERROR_INVAL;
832 return G_SPAWN_ERROR_ISDIR;
838 return G_SPAWN_ERROR_LIBBAD;
843 return G_SPAWN_ERROR_FAILED;
849 write_all (gint fd, gconstpointer vbuf, gsize to_write)
851 gchar *buf = (gchar *) vbuf;
855 gssize count = write (fd, buf, to_write);
872 write_err_and_exit (gint fd, gint msg)
876 write_all (fd, &msg, sizeof(msg));
877 write_all (fd, &en, sizeof(en));
883 set_cloexec (void *data, gint fd)
885 if (fd >= GPOINTER_TO_INT (data))
886 fcntl (fd, F_SETFD, FD_CLOEXEC);
893 fdwalk (int (*cb)(void *data, int fd), void *data)
899 #ifdef HAVE_SYS_RESOURCE_H
906 if ((d = opendir("/proc/self/fd"))) {
909 while ((de = readdir(d))) {
913 if (de->d_name[0] == '.')
917 l = strtol(de->d_name, &e, 10);
918 if (errno != 0 || !e || *e)
929 if ((res = cb (data, fd)) != 0)
937 /* If /proc is not mounted or not accessible we fall back to the old
942 #ifdef HAVE_SYS_RESOURCE_H
944 if (getrlimit(RLIMIT_NOFILE, &rl) == 0)
945 open_max = rl.rlim_max;
948 open_max = sysconf (_SC_OPEN_MAX);
950 for (fd = 0; fd < open_max; fd++)
951 if ((res = cb (data, fd)) != 0)
959 sane_dup2 (gint fd1, gint fd2)
964 ret = dup2 (fd1, fd2);
965 if (ret < 0 && errno == EINTR)
980 do_exec (gint child_err_report_fd,
984 const gchar *working_directory,
987 gboolean close_descriptors,
988 gboolean search_path,
989 gboolean stdout_to_null,
990 gboolean stderr_to_null,
991 gboolean child_inherits_stdin,
992 gboolean file_and_argv_zero,
993 GSpawnChildSetupFunc child_setup,
996 if (working_directory && chdir (working_directory) < 0)
997 write_err_and_exit (child_err_report_fd,
1000 /* Close all file descriptors but stdin stdout and stderr as
1001 * soon as we exec. Note that this includes
1002 * child_err_report_fd, which keeps the parent from blocking
1003 * forever on the other end of that pipe.
1005 if (close_descriptors)
1007 fdwalk (set_cloexec, GINT_TO_POINTER(3));
1011 /* We need to do child_err_report_fd anyway */
1012 set_cloexec (GINT_TO_POINTER(0), child_err_report_fd);
1015 /* Redirect pipes as required */
1019 /* dup2 can't actually fail here I don't think */
1021 if (sane_dup2 (stdin_fd, 0) < 0)
1022 write_err_and_exit (child_err_report_fd,
1025 /* ignore this if it doesn't work */
1026 close_and_invalidate (&stdin_fd);
1028 else if (!child_inherits_stdin)
1030 /* Keep process from blocking on a read of stdin */
1031 gint read_null = open ("/dev/null", O_RDONLY);
1032 sane_dup2 (read_null, 0);
1033 close_and_invalidate (&read_null);
1038 /* dup2 can't actually fail here I don't think */
1040 if (sane_dup2 (stdout_fd, 1) < 0)
1041 write_err_and_exit (child_err_report_fd,
1044 /* ignore this if it doesn't work */
1045 close_and_invalidate (&stdout_fd);
1047 else if (stdout_to_null)
1049 gint write_null = open ("/dev/null", O_WRONLY);
1050 sane_dup2 (write_null, 1);
1051 close_and_invalidate (&write_null);
1056 /* dup2 can't actually fail here I don't think */
1058 if (sane_dup2 (stderr_fd, 2) < 0)
1059 write_err_and_exit (child_err_report_fd,
1062 /* ignore this if it doesn't work */
1063 close_and_invalidate (&stderr_fd);
1065 else if (stderr_to_null)
1067 gint write_null = open ("/dev/null", O_WRONLY);
1068 sane_dup2 (write_null, 2);
1069 close_and_invalidate (&write_null);
1072 /* Call user function just before we exec */
1075 (* child_setup) (user_data);
1079 file_and_argv_zero ? argv + 1 : argv,
1083 write_err_and_exit (child_err_report_fd,
1100 if (bytes >= sizeof(gint)*2)
1101 break; /* give up, who knows what happened, should not be
1107 ((gchar*)buf) + bytes,
1108 sizeof(gint) * n_ints_in_buf - bytes);
1109 if (chunk < 0 && errno == EINTR)
1114 /* Some weird shit happened, bail out */
1118 G_SPAWN_ERROR_FAILED,
1119 _("Failed to read from child pipe (%s)"),
1120 g_strerror (errno));
1124 else if (chunk == 0)
1126 else /* chunk > 0 */
1130 *n_ints_read = (gint)(bytes / sizeof(gint));
1136 fork_exec_with_pipes (gboolean intermediate_child,
1137 const gchar *working_directory,
1140 gboolean close_descriptors,
1141 gboolean search_path,
1142 gboolean stdout_to_null,
1143 gboolean stderr_to_null,
1144 gboolean child_inherits_stdin,
1145 gboolean file_and_argv_zero,
1146 GSpawnChildSetupFunc child_setup,
1149 gint *standard_input,
1150 gint *standard_output,
1151 gint *standard_error,
1155 gint stdin_pipe[2] = { -1, -1 };
1156 gint stdout_pipe[2] = { -1, -1 };
1157 gint stderr_pipe[2] = { -1, -1 };
1158 gint child_err_report_pipe[2] = { -1, -1 };
1159 gint child_pid_report_pipe[2] = { -1, -1 };
1162 if (!make_pipe (child_err_report_pipe, error))
1165 if (intermediate_child && !make_pipe (child_pid_report_pipe, error))
1166 goto cleanup_and_fail;
1168 if (standard_input && !make_pipe (stdin_pipe, error))
1169 goto cleanup_and_fail;
1171 if (standard_output && !make_pipe (stdout_pipe, error))
1172 goto cleanup_and_fail;
1174 if (standard_error && !make_pipe (stderr_pipe, error))
1175 goto cleanup_and_fail;
1184 _("Failed to fork (%s)"),
1185 g_strerror (errno));
1187 goto cleanup_and_fail;
1191 /* Immediate child. This may or may not be the child that
1192 * actually execs the new process.
1195 /* Be sure we crash if the parent exits
1196 * and we write to the err_report_pipe
1198 signal (SIGPIPE, SIG_DFL);
1200 /* Close the parent's end of the pipes;
1201 * not needed in the close_descriptors case,
1204 close_and_invalidate (&child_err_report_pipe[0]);
1205 close_and_invalidate (&child_pid_report_pipe[0]);
1206 close_and_invalidate (&stdin_pipe[1]);
1207 close_and_invalidate (&stdout_pipe[0]);
1208 close_and_invalidate (&stderr_pipe[0]);
1210 if (intermediate_child)
1212 /* We need to fork an intermediate child that launches the
1213 * final child. The purpose of the intermediate child
1214 * is to exit, so we can waitpid() it immediately.
1215 * Then the grandchild will not become a zombie.
1217 GPid grandchild_pid;
1219 grandchild_pid = fork ();
1221 if (grandchild_pid < 0)
1223 /* report -1 as child PID */
1224 write_all (child_pid_report_pipe[1], &grandchild_pid,
1225 sizeof(grandchild_pid));
1227 write_err_and_exit (child_err_report_pipe[1],
1230 else if (grandchild_pid == 0)
1232 do_exec (child_err_report_pipe[1],
1243 child_inherits_stdin,
1250 write_all (child_pid_report_pipe[1], &grandchild_pid, sizeof(grandchild_pid));
1251 close_and_invalidate (&child_pid_report_pipe[1]);
1258 /* Just run the child.
1261 do_exec (child_err_report_pipe[1],
1272 child_inherits_stdin,
1285 /* Close the uncared-about ends of the pipes */
1286 close_and_invalidate (&child_err_report_pipe[1]);
1287 close_and_invalidate (&child_pid_report_pipe[1]);
1288 close_and_invalidate (&stdin_pipe[0]);
1289 close_and_invalidate (&stdout_pipe[1]);
1290 close_and_invalidate (&stderr_pipe[1]);
1292 /* If we had an intermediate child, reap it */
1293 if (intermediate_child)
1296 if (waitpid (pid, &status, 0) < 0)
1300 else if (errno == ECHILD)
1301 ; /* do nothing, child already reaped */
1303 g_warning ("waitpid() should not fail in "
1304 "'fork_exec_with_pipes'");
1309 if (!read_ints (child_err_report_pipe[0],
1312 goto cleanup_and_fail;
1316 /* Error from the child. */
1320 case CHILD_CHDIR_FAILED:
1323 G_SPAWN_ERROR_CHDIR,
1324 _("Failed to change to directory '%s' (%s)"),
1326 g_strerror (buf[1]));
1330 case CHILD_EXEC_FAILED:
1333 exec_err_to_g_error (buf[1]),
1334 _("Failed to execute child process \"%s\" (%s)"),
1336 g_strerror (buf[1]));
1340 case CHILD_DUP2_FAILED:
1343 G_SPAWN_ERROR_FAILED,
1344 _("Failed to redirect output or input of child process (%s)"),
1345 g_strerror (buf[1]));
1349 case CHILD_FORK_FAILED:
1353 _("Failed to fork child process (%s)"),
1354 g_strerror (buf[1]));
1360 G_SPAWN_ERROR_FAILED,
1361 _("Unknown error executing child process \"%s\""),
1366 goto cleanup_and_fail;
1369 /* Get child pid from intermediate child pipe. */
1370 if (intermediate_child)
1374 if (!read_ints (child_pid_report_pipe[0],
1375 buf, 1, &n_ints, error))
1376 goto cleanup_and_fail;
1382 G_SPAWN_ERROR_FAILED,
1383 _("Failed to read enough data from child pid pipe (%s)"),
1384 g_strerror (errno));
1385 goto cleanup_and_fail;
1389 /* we have the child pid */
1394 /* Success against all odds! return the information */
1395 close_and_invalidate (&child_err_report_pipe[0]);
1396 close_and_invalidate (&child_pid_report_pipe[0]);
1402 *standard_input = stdin_pipe[1];
1403 if (standard_output)
1404 *standard_output = stdout_pipe[0];
1406 *standard_error = stderr_pipe[0];
1413 /* There was an error from the Child, reap the child to avoid it being
1420 if (waitpid (pid, NULL, 0) < 0)
1424 else if (errno == ECHILD)
1425 ; /* do nothing, child already reaped */
1427 g_warning ("waitpid() should not fail in "
1428 "'fork_exec_with_pipes'");
1432 close_and_invalidate (&child_err_report_pipe[0]);
1433 close_and_invalidate (&child_err_report_pipe[1]);
1434 close_and_invalidate (&child_pid_report_pipe[0]);
1435 close_and_invalidate (&child_pid_report_pipe[1]);
1436 close_and_invalidate (&stdin_pipe[0]);
1437 close_and_invalidate (&stdin_pipe[1]);
1438 close_and_invalidate (&stdout_pipe[0]);
1439 close_and_invalidate (&stdout_pipe[1]);
1440 close_and_invalidate (&stderr_pipe[0]);
1441 close_and_invalidate (&stderr_pipe[1]);
1447 make_pipe (gint p[2],
1454 G_SPAWN_ERROR_FAILED,
1455 _("Failed to create pipe for communicating with child process (%s)"),
1456 g_strerror (errno));
1463 /* Based on execvp from GNU C Library */
1466 script_execute (const gchar *file,
1469 gboolean search_path)
1471 /* Count the arguments. */
1476 /* Construct an argument list for the shell. */
1480 new_argv = g_new0 (gchar*, argc + 2); /* /bin/sh and NULL */
1482 new_argv[0] = (char *) "/bin/sh";
1483 new_argv[1] = (char *) file;
1486 new_argv[argc + 1] = argv[argc];
1490 /* Execute the shell. */
1492 execve (new_argv[0], new_argv, envp);
1494 execv (new_argv[0], new_argv);
1501 my_strchrnul (const gchar *str, gchar c)
1503 gchar *p = (gchar*) str;
1504 while (*p && (*p != c))
1511 g_execute (const gchar *file,
1514 gboolean search_path)
1518 /* We check the simple case first. */
1523 if (!search_path || strchr (file, '/') != NULL)
1525 /* Don't search when it contains a slash. */
1527 execve (file, argv, envp);
1531 if (errno == ENOEXEC)
1532 script_execute (file, argv, envp, FALSE);
1536 gboolean got_eacces = 0;
1537 const gchar *path, *p;
1538 gchar *name, *freeme;
1542 path = g_getenv ("PATH");
1545 /* There is no `PATH' in the environment. The default
1546 * search path in libc is the current directory followed by
1547 * the path `confstr' returns for `_CS_PATH'.
1550 /* In GLib we put . last, for security, and don't use the
1551 * unportable confstr(); UNIX98 does not actually specify
1552 * what to search if PATH is unset. POSIX may, dunno.
1555 path = "/bin:/usr/bin:.";
1558 len = strlen (file) + 1;
1559 pathlen = strlen (path);
1560 freeme = name = g_malloc (pathlen + len + 1);
1562 /* Copy the file name at the top, including '\0' */
1563 memcpy (name + pathlen + 1, file, len);
1564 name = name + pathlen;
1565 /* And add the slash before the filename */
1574 p = my_strchrnul (path, ':');
1577 /* Two adjacent colons, or a colon at the beginning or the end
1578 * of `PATH' means to search the current directory.
1582 startp = memcpy (name - (p - path), path, p - path);
1584 /* Try to execute this name. If it works, execv will not return. */
1586 execve (startp, argv, envp);
1588 execv (startp, argv);
1590 if (errno == ENOEXEC)
1591 script_execute (startp, argv, envp, search_path);
1596 /* Record the we got a `Permission denied' error. If we end
1597 * up finding no executable we can use, we want to diagnose
1598 * that we did find one but were denied access.
1611 /* Those errors indicate the file is missing or not executable
1612 * by us, in which case we want to just try the next path
1618 /* Some other error means we found an executable file, but
1619 * something went wrong executing it; return the error to our
1626 while (*p++ != '\0');
1628 /* We tried every element and none of them worked. */
1630 /* At least one failure was due to permissions, so report that
1638 /* Return the error from the last attempt (probably ENOENT). */
1643 * g_spawn_close_pid:
1644 * @pid: The process identifier to close
1646 * On some platforms, notably WIN32, the #GPid type represents a resource
1647 * which must be closed to prevent resource leaking. g_spawn_close_pid()
1648 * is provided for this purpose. It should be used on all platforms, even
1649 * though it doesn't do anything under UNIX.
1652 g_spawn_close_pid (GPid pid)
1656 #define __G_SPAWN_C__
1657 #include "galiasdef.c"