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 */
47 static gint g_execute (const gchar *file,
50 gboolean search_path);
52 static gboolean make_pipe (gint p[2],
54 static gboolean fork_exec_with_pipes (gboolean intermediate_child,
55 const gchar *working_directory,
58 gboolean close_descriptors,
60 gboolean stdout_to_null,
61 gboolean stderr_to_null,
62 gboolean child_inherits_stdin,
63 gboolean file_and_argv_zero,
64 GSpawnChildSetupFunc child_setup,
68 gint *standard_output,
73 g_spawn_error_quark (void)
75 return g_quark_from_static_string ("g-exec-error-quark");
80 * @working_directory: child's current working directory, or %NULL to inherit parent's
81 * @argv: child's argument vector
82 * @envp: child's environment, or %NULL to inherit parent's
83 * @flags: flags from #GSpawnFlags
84 * @child_setup: function to run in the child just before exec()
85 * @user_data: user data for @child_setup
86 * @child_pid: return location for child process reference, or %NULL
87 * @error: return location for error
89 * See g_spawn_async_with_pipes() for a full description; this function
90 * simply calls the g_spawn_async_with_pipes() without any pipes.
92 * You should call g_spawn_close_pid() on the returned child process
93 * reference when you don't need it any more.
96 * If you are writing a GTK+ application, and the program you
97 * are spawning is a graphical application, too, then you may
98 * want to use gdk_spawn_on_screen() instead to ensure that
99 * the spawned program opens its windows on the right screen.
102 * <note><para> Note that the returned @child_pid on Windows is a
103 * handle to the child process and not its identifier. Process handles
104 * and process identifiers are different concepts on Windows.
107 * Return value: %TRUE on success, %FALSE if error is set
110 g_spawn_async (const gchar *working_directory,
114 GSpawnChildSetupFunc child_setup,
119 g_return_val_if_fail (argv != NULL, FALSE);
121 return g_spawn_async_with_pipes (working_directory,
131 /* Avoids a danger in threaded situations (calling close()
132 * on a file descriptor twice, and another thread has
133 * re-opened it since the first close)
136 close_and_invalidate (gint *fd)
151 /* Some versions of OS X define READ_OK in public headers */
156 READ_FAILED = 0, /* FALSE */
162 read_data (GString *str,
171 bytes = read (fd, buf, 4096);
177 g_string_append_len (str, buf, bytes);
180 else if (bytes < 0 && errno == EINTR)
189 _("Failed to read data from child process (%s)"),
200 * @working_directory: child's current working directory, or %NULL to inherit parent's
201 * @argv: child's argument vector
202 * @envp: child's environment, or %NULL to inherit parent's
203 * @flags: flags from #GSpawnFlags
204 * @child_setup: function to run in the child just before exec()
205 * @user_data: user data for @child_setup
206 * @standard_output: return location for child output, or %NULL
207 * @standard_error: return location for child error messages, or %NULL
208 * @exit_status: return location for child exit status, as returned by waitpid(), or %NULL
209 * @error: return location for error, or %NULL
211 * Executes a child synchronously (waits for the child to exit before returning).
212 * All output from the child is stored in @standard_output and @standard_error,
213 * if those parameters are non-%NULL. Note that you must set the
214 * %G_SPAWN_STDOUT_TO_DEV_NULL and %G_SPAWN_STDERR_TO_DEV_NULL flags when
215 * passing %NULL for @standard_output and @standard_error.
216 * If @exit_status is non-%NULL, the exit status of the child is stored
217 * there as it would be returned by waitpid(); standard UNIX macros such
218 * as WIFEXITED() and WEXITSTATUS() must be used to evaluate the exit status.
219 * Note that this function call waitpid() even if @exit_status is %NULL, and
220 * does not accept the %G_SPAWN_DO_NOT_REAP_CHILD flag.
221 * If an error occurs, no data is returned in @standard_output,
222 * @standard_error, or @exit_status.
224 * This function calls g_spawn_async_with_pipes() internally; see that
225 * function for full details on the other parameters and details on
226 * how these functions work on Windows.
228 * Return value: %TRUE on success, %FALSE if an error was set.
231 g_spawn_sync (const gchar *working_directory,
235 GSpawnChildSetupFunc child_setup,
237 gchar **standard_output,
238 gchar **standard_error,
247 GString *outstr = NULL;
248 GString *errstr = NULL;
252 g_return_val_if_fail (argv != NULL, FALSE);
253 g_return_val_if_fail (!(flags & G_SPAWN_DO_NOT_REAP_CHILD), FALSE);
254 g_return_val_if_fail (standard_output == NULL ||
255 !(flags & G_SPAWN_STDOUT_TO_DEV_NULL), FALSE);
256 g_return_val_if_fail (standard_error == NULL ||
257 !(flags & G_SPAWN_STDERR_TO_DEV_NULL), FALSE);
259 /* Just to ensure segfaults if callers try to use
260 * these when an error is reported.
263 *standard_output = NULL;
266 *standard_error = NULL;
268 if (!fork_exec_with_pipes (FALSE,
272 !(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN),
273 (flags & G_SPAWN_SEARCH_PATH) != 0,
274 (flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0,
275 (flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0,
276 (flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0,
277 (flags & G_SPAWN_FILE_AND_ARGV_ZERO) != 0,
282 standard_output ? &outpipe : NULL,
283 standard_error ? &errpipe : NULL,
287 /* Read data from child. */
293 outstr = g_string_new (NULL);
298 errstr = g_string_new (NULL);
301 /* Read data until we get EOF on both pipes. */
310 FD_SET (outpipe, &fds);
312 FD_SET (errpipe, &fds);
314 ret = select (MAX (outpipe, errpipe) + 1,
317 NULL /* no timeout */);
319 if (ret < 0 && errno != EINTR)
328 _("Unexpected error in select() reading data from a child process (%s)"),
334 if (outpipe >= 0 && FD_ISSET (outpipe, &fds))
336 switch (read_data (outstr, outpipe, error))
342 close_and_invalidate (&outpipe);
353 if (errpipe >= 0 && FD_ISSET (errpipe, &fds))
355 switch (read_data (errstr, errpipe, error))
361 close_and_invalidate (&errpipe);
373 /* These should only be open still if we had an error. */
376 close_and_invalidate (&outpipe);
378 close_and_invalidate (&errpipe);
380 /* Wait for child to exit, even if we have
385 ret = waitpid (pid, &status, 0);
391 else if (errno == ECHILD)
395 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.");
399 /* We don't need the exit status. */
404 if (!failed) /* avoid error pileups */
413 _("Unexpected error in waitpid() (%s)"),
422 g_string_free (outstr, TRUE);
424 g_string_free (errstr, TRUE);
431 *exit_status = status;
434 *standard_output = g_string_free (outstr, FALSE);
437 *standard_error = g_string_free (errstr, FALSE);
444 * g_spawn_async_with_pipes:
445 * @working_directory: child's current working directory, or %NULL to inherit parent's, in the GLib file name encoding
446 * @argv: child's argument vector, in the GLib file name encoding
447 * @envp: child's environment, or %NULL to inherit parent's, in the GLib file name encoding
448 * @flags: flags from #GSpawnFlags
449 * @child_setup: function to run in the child just before exec()
450 * @user_data: user data for @child_setup
451 * @child_pid: return location for child process ID, or %NULL
452 * @standard_input: return location for file descriptor to write to child's stdin, or %NULL
453 * @standard_output: return location for file descriptor to read child's stdout, or %NULL
454 * @standard_error: return location for file descriptor to read child's stderr, or %NULL
455 * @error: return location for error
457 * Executes a child program asynchronously (your program will not
458 * block waiting for the child to exit). The child program is
459 * specified by the only argument that must be provided, @argv. @argv
460 * should be a %NULL-terminated array of strings, to be passed as the
461 * argument vector for the child. The first string in @argv is of
462 * course the name of the program to execute. By default, the name of
463 * the program must be a full path; the <envar>PATH</envar> shell variable
464 * will only be searched if you pass the %G_SPAWN_SEARCH_PATH flag.
466 * On Windows, note that all the string or string vector arguments to
467 * this function and the other g_spawn*() functions are in UTF-8, the
468 * GLib file name encoding. Unicode characters that are not part of
469 * the system codepage passed in these arguments will be correctly
470 * available in the spawned program only if it uses wide character API
471 * to retrieve its command line. For C programs built with Microsoft's
472 * tools it is enough to make the program have a wmain() instead of
473 * main(). wmain() has a wide character argument vector as parameter.
475 * At least currently, mingw doesn't support wmain(), so if you use
476 * mingw to develop the spawned program, it will have to call the
477 * undocumented function __wgetmainargs() to get the wide character
478 * argument vector and environment. See gspawn-win32-helper.c in the
479 * GLib sources or init.c in the mingw runtime sources for a prototype
480 * for that function. Alternatively, you can retrieve the Win32 system
481 * level wide character command line passed to the spawned program
482 * using the GetCommandLineW() function.
484 * On Windows the low-level child process creation API
485 * <function>CreateProcess()</function> doesn't use argument vectors,
486 * but a command line. The C runtime library's
487 * <function>spawn*()</function> family of functions (which
488 * g_spawn_async_with_pipes() eventually calls) paste the argument
489 * vector elements together into a command line, and the C runtime startup code
490 * does a corresponding reconstruction of an argument vector from the
491 * command line, to be passed to main(). Complications arise when you have
492 * argument vector elements that contain spaces of double quotes. The
493 * <function>spawn*()</function> functions don't do any quoting or
494 * escaping, but on the other hand the startup code does do unquoting
495 * and unescaping in order to enable receiving arguments with embedded
496 * spaces or double quotes. To work around this asymmetry,
497 * g_spawn_async_with_pipes() will do quoting and escaping on argument
498 * vector elements that need it before calling the C runtime
501 * The returned @child_pid on Windows is a handle to the child
502 * process, not its identifier. Process handles and process
503 * identifiers are different concepts on Windows.
505 * @envp is a %NULL-terminated array of strings, where each string
506 * has the form <literal>KEY=VALUE</literal>. This will become
507 * the child's environment. If @envp is %NULL, the child inherits its
508 * parent's environment.
510 * @flags should be the bitwise OR of any flags you want to affect the
511 * function's behaviour. The %G_SPAWN_DO_NOT_REAP_CHILD means that
512 * the child will not automatically be reaped; you must use a
513 * #GChildWatch source to be notified about the death of the child
514 * process. Eventually you must call g_spawn_close_pid() on the
515 * @child_pid, in order to free resources which may be associated
516 * with the child process. (On Unix, using a #GChildWatch source is
517 * equivalent to calling waitpid() or handling the %SIGCHLD signal
518 * manually. On Windows, calling g_spawn_close_pid() is equivalent
519 * to calling CloseHandle() on the process handle returned in
522 * %G_SPAWN_LEAVE_DESCRIPTORS_OPEN means that the parent's open file
523 * descriptors will be inherited by the child; otherwise all
524 * descriptors except stdin/stdout/stderr will be closed before
525 * calling exec() in the child. %G_SPAWN_SEARCH_PATH
526 * means that <literal>argv[0]</literal> need not be an absolute path, it
527 * will be looked for in the user's <envar>PATH</envar>.
528 * %G_SPAWN_STDOUT_TO_DEV_NULL means that the child's standard output will
529 * be discarded, instead of going to the same location as the parent's
530 * standard output. If you use this flag, @standard_output must be %NULL.
531 * %G_SPAWN_STDERR_TO_DEV_NULL means that the child's standard error
532 * will be discarded, instead of going to the same location as the parent's
533 * standard error. If you use this flag, @standard_error must be %NULL.
534 * %G_SPAWN_CHILD_INHERITS_STDIN means that the child will inherit the parent's
535 * standard input (by default, the child's standard input is attached to
536 * /dev/null). If you use this flag, @standard_input must be %NULL.
537 * %G_SPAWN_FILE_AND_ARGV_ZERO means that the first element of @argv is
538 * the file to execute, while the remaining elements are the
539 * actual argument vector to pass to the file. Normally
540 * g_spawn_async_with_pipes() uses @argv[0] as the file to execute, and
541 * passes all of @argv to the child.
543 * @child_setup and @user_data are a function and user data. On POSIX
544 * platforms, the function is called in the child after GLib has
545 * performed all the setup it plans to perform (including creating
546 * pipes, closing file descriptors, etc.) but before calling
547 * exec(). That is, @child_setup is called just
548 * before calling exec() in the child. Obviously
549 * actions taken in this function will only affect the child, not the
552 * On Windows, there is no separate fork() and exec()
553 * functionality. Child processes are created and run with a single
554 * API call, CreateProcess(). There is no sensible thing @child_setup
555 * could be used for on Windows so it is ignored and not called.
557 * If non-%NULL, @child_pid will on Unix be filled with the child's
558 * process ID. You can use the process ID to send signals to the
559 * child, or to use g_child_watch_add() (or waitpid()) if you specified the
560 * %G_SPAWN_DO_NOT_REAP_CHILD flag. On Windows, @child_pid will be
561 * filled with a handle to the child process only if you specified the
562 * %G_SPAWN_DO_NOT_REAP_CHILD flag. You can then access the child
563 * process using the Win32 API, for example wait for its termination
564 * with the <function>WaitFor*()</function> functions, or examine its
565 * exit code with GetExitCodeProcess(). You should close the handle
566 * with CloseHandle() or g_spawn_close_pid() when you no longer need it.
568 * If non-%NULL, the @standard_input, @standard_output, @standard_error
569 * locations will be filled with file descriptors for writing to the child's
570 * standard input or reading from its standard output or standard error.
571 * The caller of g_spawn_async_with_pipes() must close these file descriptors
572 * when they are no longer in use. If these parameters are %NULL, the corresponding
573 * pipe won't be created.
575 * If @standard_input is NULL, the child's standard input is attached to
576 * /dev/null unless %G_SPAWN_CHILD_INHERITS_STDIN is set.
578 * If @standard_error is NULL, the child's standard error goes to the same
579 * location as the parent's standard error unless %G_SPAWN_STDERR_TO_DEV_NULL
582 * If @standard_output is NULL, the child's standard output goes to the same
583 * location as the parent's standard output unless %G_SPAWN_STDOUT_TO_DEV_NULL
586 * @error can be %NULL to ignore errors, or non-%NULL to report errors.
587 * If an error is set, the function returns %FALSE. Errors
588 * are reported even if they occur in the child (for example if the
589 * executable in <literal>argv[0]</literal> is not found). Typically
590 * the <literal>message</literal> field of returned errors should be displayed
591 * to users. Possible errors are those from the #G_SPAWN_ERROR domain.
593 * If an error occurs, @child_pid, @standard_input, @standard_output,
594 * and @standard_error will not be filled with valid values.
596 * If @child_pid is not %NULL and an error does not occur then the returned
597 * process reference must be closed using g_spawn_close_pid().
600 * If you are writing a GTK+ application, and the program you
601 * are spawning is a graphical application, too, then you may
602 * want to use gdk_spawn_on_screen_with_pipes() instead to ensure that
603 * the spawned program opens its windows on the right screen.
606 * Return value: %TRUE on success, %FALSE if an error was set
609 g_spawn_async_with_pipes (const gchar *working_directory,
613 GSpawnChildSetupFunc child_setup,
616 gint *standard_input,
617 gint *standard_output,
618 gint *standard_error,
621 g_return_val_if_fail (argv != NULL, FALSE);
622 g_return_val_if_fail (standard_output == NULL ||
623 !(flags & G_SPAWN_STDOUT_TO_DEV_NULL), FALSE);
624 g_return_val_if_fail (standard_error == NULL ||
625 !(flags & G_SPAWN_STDERR_TO_DEV_NULL), FALSE);
626 /* can't inherit stdin if we have an input pipe. */
627 g_return_val_if_fail (standard_input == NULL ||
628 !(flags & G_SPAWN_CHILD_INHERITS_STDIN), FALSE);
630 return fork_exec_with_pipes (!(flags & G_SPAWN_DO_NOT_REAP_CHILD),
634 !(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN),
635 (flags & G_SPAWN_SEARCH_PATH) != 0,
636 (flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0,
637 (flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0,
638 (flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0,
639 (flags & G_SPAWN_FILE_AND_ARGV_ZERO) != 0,
650 * g_spawn_command_line_sync:
651 * @command_line: a command line
652 * @standard_output: return location for child output
653 * @standard_error: return location for child errors
654 * @exit_status: return location for child exit status, as returned by waitpid()
655 * @error: return location for errors
657 * A simple version of g_spawn_sync() with little-used parameters
658 * removed, taking a command line instead of an argument vector. See
659 * g_spawn_sync() for full details. @command_line will be parsed by
660 * g_shell_parse_argv(). Unlike g_spawn_sync(), the %G_SPAWN_SEARCH_PATH flag
661 * is enabled. Note that %G_SPAWN_SEARCH_PATH can have security
662 * implications, so consider using g_spawn_sync() directly if
663 * appropriate. Possible errors are those from g_spawn_sync() and those
664 * from g_shell_parse_argv().
666 * If @exit_status is non-%NULL, the exit status of the child is stored there as
667 * it would be returned by waitpid(); standard UNIX macros such as WIFEXITED()
668 * and WEXITSTATUS() must be used to evaluate the exit status.
670 * On Windows, please note the implications of g_shell_parse_argv()
671 * parsing @command_line. Parsing is done according to Unix shell rules, not
672 * Windows command interpreter rules.
673 * Space is a separator, and backslashes are
674 * special. Thus you cannot simply pass a @command_line containing
675 * canonical Windows paths, like "c:\\program files\\app\\app.exe", as
676 * the backslashes will be eaten, and the space will act as a
677 * separator. You need to enclose such paths with single quotes, like
678 * "'c:\\program files\\app\\app.exe' 'e:\\folder\\argument.txt'".
680 * Return value: %TRUE on success, %FALSE if an error was set
683 g_spawn_command_line_sync (const gchar *command_line,
684 gchar **standard_output,
685 gchar **standard_error,
692 g_return_val_if_fail (command_line != NULL, FALSE);
694 if (!g_shell_parse_argv (command_line,
699 retval = g_spawn_sync (NULL,
715 * g_spawn_command_line_async:
716 * @command_line: a command line
717 * @error: return location for errors
719 * A simple version of g_spawn_async() that parses a command line with
720 * g_shell_parse_argv() and passes it to g_spawn_async(). Runs a
721 * command line in the background. Unlike g_spawn_async(), the
722 * %G_SPAWN_SEARCH_PATH flag is enabled, other flags are not. Note
723 * that %G_SPAWN_SEARCH_PATH can have security implications, so
724 * consider using g_spawn_async() directly if appropriate. Possible
725 * errors are those from g_shell_parse_argv() and g_spawn_async().
727 * The same concerns on Windows apply as for g_spawn_command_line_sync().
729 * Return value: %TRUE on success, %FALSE if error is set.
732 g_spawn_command_line_async (const gchar *command_line,
738 g_return_val_if_fail (command_line != NULL, FALSE);
740 if (!g_shell_parse_argv (command_line,
745 retval = g_spawn_async (NULL,
759 exec_err_to_g_error (gint en)
765 return G_SPAWN_ERROR_ACCES;
771 return G_SPAWN_ERROR_PERM;
777 return G_SPAWN_ERROR_2BIG;
783 return G_SPAWN_ERROR_NOEXEC;
789 return G_SPAWN_ERROR_NAMETOOLONG;
795 return G_SPAWN_ERROR_NOENT;
801 return G_SPAWN_ERROR_NOMEM;
807 return G_SPAWN_ERROR_NOTDIR;
813 return G_SPAWN_ERROR_LOOP;
819 return G_SPAWN_ERROR_TXTBUSY;
825 return G_SPAWN_ERROR_IO;
831 return G_SPAWN_ERROR_NFILE;
837 return G_SPAWN_ERROR_MFILE;
843 return G_SPAWN_ERROR_INVAL;
849 return G_SPAWN_ERROR_ISDIR;
855 return G_SPAWN_ERROR_LIBBAD;
860 return G_SPAWN_ERROR_FAILED;
866 write_all (gint fd, gconstpointer vbuf, gsize to_write)
868 gchar *buf = (gchar *) vbuf;
872 gssize count = write (fd, buf, to_write);
890 write_err_and_exit (gint fd, gint msg)
894 write_all (fd, &msg, sizeof(msg));
895 write_all (fd, &en, sizeof(en));
901 set_cloexec (void *data, gint fd)
903 if (fd >= GPOINTER_TO_INT (data))
904 fcntl (fd, F_SETFD, FD_CLOEXEC);
911 fdwalk (int (*cb)(void *data, int fd), void *data)
917 #ifdef HAVE_SYS_RESOURCE_H
924 if ((d = opendir("/proc/self/fd"))) {
927 while ((de = readdir(d))) {
931 if (de->d_name[0] == '.')
935 l = strtol(de->d_name, &e, 10);
936 if (errno != 0 || !e || *e)
947 if ((res = cb (data, fd)) != 0)
955 /* If /proc is not mounted or not accessible we fall back to the old
960 #ifdef HAVE_SYS_RESOURCE_H
962 if (getrlimit(RLIMIT_NOFILE, &rl) == 0 && rl.rlim_max != RLIM_INFINITY)
963 open_max = rl.rlim_max;
966 open_max = sysconf (_SC_OPEN_MAX);
968 for (fd = 0; fd < open_max; fd++)
969 if ((res = cb (data, fd)) != 0)
977 sane_dup2 (gint fd1, gint fd2)
982 ret = dup2 (fd1, fd2);
983 if (ret < 0 && errno == EINTR)
998 do_exec (gint child_err_report_fd,
1002 const gchar *working_directory,
1005 gboolean close_descriptors,
1006 gboolean search_path,
1007 gboolean stdout_to_null,
1008 gboolean stderr_to_null,
1009 gboolean child_inherits_stdin,
1010 gboolean file_and_argv_zero,
1011 GSpawnChildSetupFunc child_setup,
1014 if (working_directory && chdir (working_directory) < 0)
1015 write_err_and_exit (child_err_report_fd,
1016 CHILD_CHDIR_FAILED);
1018 /* Close all file descriptors but stdin stdout and stderr as
1019 * soon as we exec. Note that this includes
1020 * child_err_report_fd, which keeps the parent from blocking
1021 * forever on the other end of that pipe.
1023 if (close_descriptors)
1025 fdwalk (set_cloexec, GINT_TO_POINTER(3));
1029 /* We need to do child_err_report_fd anyway */
1030 set_cloexec (GINT_TO_POINTER(0), child_err_report_fd);
1033 /* Redirect pipes as required */
1037 /* dup2 can't actually fail here I don't think */
1039 if (sane_dup2 (stdin_fd, 0) < 0)
1040 write_err_and_exit (child_err_report_fd,
1043 /* ignore this if it doesn't work */
1044 close_and_invalidate (&stdin_fd);
1046 else if (!child_inherits_stdin)
1048 /* Keep process from blocking on a read of stdin */
1049 gint read_null = open ("/dev/null", O_RDONLY);
1050 sane_dup2 (read_null, 0);
1051 close_and_invalidate (&read_null);
1056 /* dup2 can't actually fail here I don't think */
1058 if (sane_dup2 (stdout_fd, 1) < 0)
1059 write_err_and_exit (child_err_report_fd,
1062 /* ignore this if it doesn't work */
1063 close_and_invalidate (&stdout_fd);
1065 else if (stdout_to_null)
1067 gint write_null = open ("/dev/null", O_WRONLY);
1068 sane_dup2 (write_null, 1);
1069 close_and_invalidate (&write_null);
1074 /* dup2 can't actually fail here I don't think */
1076 if (sane_dup2 (stderr_fd, 2) < 0)
1077 write_err_and_exit (child_err_report_fd,
1080 /* ignore this if it doesn't work */
1081 close_and_invalidate (&stderr_fd);
1083 else if (stderr_to_null)
1085 gint write_null = open ("/dev/null", O_WRONLY);
1086 sane_dup2 (write_null, 2);
1087 close_and_invalidate (&write_null);
1090 /* Call user function just before we exec */
1093 (* child_setup) (user_data);
1097 file_and_argv_zero ? argv + 1 : argv,
1101 write_err_and_exit (child_err_report_fd,
1118 if (bytes >= sizeof(gint)*2)
1119 break; /* give up, who knows what happened, should not be
1125 ((gchar*)buf) + bytes,
1126 sizeof(gint) * n_ints_in_buf - bytes);
1127 if (chunk < 0 && errno == EINTR)
1134 /* Some weird shit happened, bail out */
1137 G_SPAWN_ERROR_FAILED,
1138 _("Failed to read from child pipe (%s)"),
1139 g_strerror (errsv));
1143 else if (chunk == 0)
1145 else /* chunk > 0 */
1149 *n_ints_read = (gint)(bytes / sizeof(gint));
1155 fork_exec_with_pipes (gboolean intermediate_child,
1156 const gchar *working_directory,
1159 gboolean close_descriptors,
1160 gboolean search_path,
1161 gboolean stdout_to_null,
1162 gboolean stderr_to_null,
1163 gboolean child_inherits_stdin,
1164 gboolean file_and_argv_zero,
1165 GSpawnChildSetupFunc child_setup,
1168 gint *standard_input,
1169 gint *standard_output,
1170 gint *standard_error,
1174 gint stdin_pipe[2] = { -1, -1 };
1175 gint stdout_pipe[2] = { -1, -1 };
1176 gint stderr_pipe[2] = { -1, -1 };
1177 gint child_err_report_pipe[2] = { -1, -1 };
1178 gint child_pid_report_pipe[2] = { -1, -1 };
1181 if (!make_pipe (child_err_report_pipe, error))
1184 if (intermediate_child && !make_pipe (child_pid_report_pipe, error))
1185 goto cleanup_and_fail;
1187 if (standard_input && !make_pipe (stdin_pipe, error))
1188 goto cleanup_and_fail;
1190 if (standard_output && !make_pipe (stdout_pipe, error))
1191 goto cleanup_and_fail;
1193 if (standard_error && !make_pipe (stderr_pipe, error))
1194 goto cleanup_and_fail;
1205 _("Failed to fork (%s)"),
1206 g_strerror (errsv));
1208 goto cleanup_and_fail;
1212 /* Immediate child. This may or may not be the child that
1213 * actually execs the new process.
1216 /* Be sure we crash if the parent exits
1217 * and we write to the err_report_pipe
1219 signal (SIGPIPE, SIG_DFL);
1221 /* Close the parent's end of the pipes;
1222 * not needed in the close_descriptors case,
1225 close_and_invalidate (&child_err_report_pipe[0]);
1226 close_and_invalidate (&child_pid_report_pipe[0]);
1227 close_and_invalidate (&stdin_pipe[1]);
1228 close_and_invalidate (&stdout_pipe[0]);
1229 close_and_invalidate (&stderr_pipe[0]);
1231 if (intermediate_child)
1233 /* We need to fork an intermediate child that launches the
1234 * final child. The purpose of the intermediate child
1235 * is to exit, so we can waitpid() it immediately.
1236 * Then the grandchild will not become a zombie.
1238 GPid grandchild_pid;
1240 grandchild_pid = fork ();
1242 if (grandchild_pid < 0)
1244 /* report -1 as child PID */
1245 write_all (child_pid_report_pipe[1], &grandchild_pid,
1246 sizeof(grandchild_pid));
1248 write_err_and_exit (child_err_report_pipe[1],
1251 else if (grandchild_pid == 0)
1253 do_exec (child_err_report_pipe[1],
1264 child_inherits_stdin,
1271 write_all (child_pid_report_pipe[1], &grandchild_pid, sizeof(grandchild_pid));
1272 close_and_invalidate (&child_pid_report_pipe[1]);
1279 /* Just run the child.
1282 do_exec (child_err_report_pipe[1],
1293 child_inherits_stdin,
1306 /* Close the uncared-about ends of the pipes */
1307 close_and_invalidate (&child_err_report_pipe[1]);
1308 close_and_invalidate (&child_pid_report_pipe[1]);
1309 close_and_invalidate (&stdin_pipe[0]);
1310 close_and_invalidate (&stdout_pipe[1]);
1311 close_and_invalidate (&stderr_pipe[1]);
1313 /* If we had an intermediate child, reap it */
1314 if (intermediate_child)
1317 if (waitpid (pid, &status, 0) < 0)
1321 else if (errno == ECHILD)
1322 ; /* do nothing, child already reaped */
1324 g_warning ("waitpid() should not fail in "
1325 "'fork_exec_with_pipes'");
1330 if (!read_ints (child_err_report_pipe[0],
1333 goto cleanup_and_fail;
1337 /* Error from the child. */
1341 case CHILD_CHDIR_FAILED:
1344 G_SPAWN_ERROR_CHDIR,
1345 _("Failed to change to directory '%s' (%s)"),
1347 g_strerror (buf[1]));
1351 case CHILD_EXEC_FAILED:
1354 exec_err_to_g_error (buf[1]),
1355 _("Failed to execute child process \"%s\" (%s)"),
1357 g_strerror (buf[1]));
1361 case CHILD_DUP2_FAILED:
1364 G_SPAWN_ERROR_FAILED,
1365 _("Failed to redirect output or input of child process (%s)"),
1366 g_strerror (buf[1]));
1370 case CHILD_FORK_FAILED:
1374 _("Failed to fork child process (%s)"),
1375 g_strerror (buf[1]));
1381 G_SPAWN_ERROR_FAILED,
1382 _("Unknown error executing child process \"%s\""),
1387 goto cleanup_and_fail;
1390 /* Get child pid from intermediate child pipe. */
1391 if (intermediate_child)
1395 if (!read_ints (child_pid_report_pipe[0],
1396 buf, 1, &n_ints, error))
1397 goto cleanup_and_fail;
1405 G_SPAWN_ERROR_FAILED,
1406 _("Failed to read enough data from child pid pipe (%s)"),
1407 g_strerror (errsv));
1408 goto cleanup_and_fail;
1412 /* we have the child pid */
1417 /* Success against all odds! return the information */
1418 close_and_invalidate (&child_err_report_pipe[0]);
1419 close_and_invalidate (&child_pid_report_pipe[0]);
1425 *standard_input = stdin_pipe[1];
1426 if (standard_output)
1427 *standard_output = stdout_pipe[0];
1429 *standard_error = stderr_pipe[0];
1436 /* There was an error from the Child, reap the child to avoid it being
1443 if (waitpid (pid, NULL, 0) < 0)
1447 else if (errno == ECHILD)
1448 ; /* do nothing, child already reaped */
1450 g_warning ("waitpid() should not fail in "
1451 "'fork_exec_with_pipes'");
1455 close_and_invalidate (&child_err_report_pipe[0]);
1456 close_and_invalidate (&child_err_report_pipe[1]);
1457 close_and_invalidate (&child_pid_report_pipe[0]);
1458 close_and_invalidate (&child_pid_report_pipe[1]);
1459 close_and_invalidate (&stdin_pipe[0]);
1460 close_and_invalidate (&stdin_pipe[1]);
1461 close_and_invalidate (&stdout_pipe[0]);
1462 close_and_invalidate (&stdout_pipe[1]);
1463 close_and_invalidate (&stderr_pipe[0]);
1464 close_and_invalidate (&stderr_pipe[1]);
1470 make_pipe (gint p[2],
1478 G_SPAWN_ERROR_FAILED,
1479 _("Failed to create pipe for communicating with child process (%s)"),
1480 g_strerror (errsv));
1487 /* Based on execvp from GNU C Library */
1490 script_execute (const gchar *file,
1493 gboolean search_path)
1495 /* Count the arguments. */
1500 /* Construct an argument list for the shell. */
1504 new_argv = g_new0 (gchar*, argc + 2); /* /bin/sh and NULL */
1506 new_argv[0] = (char *) "/bin/sh";
1507 new_argv[1] = (char *) file;
1510 new_argv[argc + 1] = argv[argc];
1514 /* Execute the shell. */
1516 execve (new_argv[0], new_argv, envp);
1518 execv (new_argv[0], new_argv);
1525 my_strchrnul (const gchar *str, gchar c)
1527 gchar *p = (gchar*) str;
1528 while (*p && (*p != c))
1535 g_execute (const gchar *file,
1538 gboolean search_path)
1542 /* We check the simple case first. */
1547 if (!search_path || strchr (file, '/') != NULL)
1549 /* Don't search when it contains a slash. */
1551 execve (file, argv, envp);
1555 if (errno == ENOEXEC)
1556 script_execute (file, argv, envp, FALSE);
1560 gboolean got_eacces = 0;
1561 const gchar *path, *p;
1562 gchar *name, *freeme;
1566 path = g_getenv ("PATH");
1569 /* There is no `PATH' in the environment. The default
1570 * search path in libc is the current directory followed by
1571 * the path `confstr' returns for `_CS_PATH'.
1574 /* In GLib we put . last, for security, and don't use the
1575 * unportable confstr(); UNIX98 does not actually specify
1576 * what to search if PATH is unset. POSIX may, dunno.
1579 path = "/bin:/usr/bin:.";
1582 len = strlen (file) + 1;
1583 pathlen = strlen (path);
1584 freeme = name = g_malloc (pathlen + len + 1);
1586 /* Copy the file name at the top, including '\0' */
1587 memcpy (name + pathlen + 1, file, len);
1588 name = name + pathlen;
1589 /* And add the slash before the filename */
1598 p = my_strchrnul (path, ':');
1601 /* Two adjacent colons, or a colon at the beginning or the end
1602 * of `PATH' means to search the current directory.
1606 startp = memcpy (name - (p - path), path, p - path);
1608 /* Try to execute this name. If it works, execv will not return. */
1610 execve (startp, argv, envp);
1612 execv (startp, argv);
1614 if (errno == ENOEXEC)
1615 script_execute (startp, argv, envp, search_path);
1620 /* Record the we got a `Permission denied' error. If we end
1621 * up finding no executable we can use, we want to diagnose
1622 * that we did find one but were denied access.
1635 /* Those errors indicate the file is missing or not executable
1636 * by us, in which case we want to just try the next path
1642 /* Some other error means we found an executable file, but
1643 * something went wrong executing it; return the error to our
1650 while (*p++ != '\0');
1652 /* We tried every element and none of them worked. */
1654 /* At least one failure was due to permissions, so report that
1662 /* Return the error from the last attempt (probably ENOENT). */
1667 * g_spawn_close_pid:
1668 * @pid: The process reference to close
1670 * On some platforms, notably Windows, the #GPid type represents a resource
1671 * which must be closed to prevent resource leaking. g_spawn_close_pid()
1672 * is provided for this purpose. It should be used on all platforms, even
1673 * though it doesn't do anything under UNIX.
1676 g_spawn_close_pid (GPid pid)