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>
34 #ifdef HAVE_SYS_SELECT_H
35 #include <sys/select.h>
36 #endif /* HAVE_SYS_SELECT_H */
42 static gint g_execute (const gchar *file,
45 gboolean search_path);
47 static gboolean make_pipe (gint p[2],
49 static gboolean fork_exec_with_pipes (gboolean intermediate_child,
50 const gchar *working_directory,
53 gboolean close_descriptors,
55 gboolean stdout_to_null,
56 gboolean stderr_to_null,
57 gboolean child_inherits_stdin,
58 gboolean file_and_argv_zero,
59 GSpawnChildSetupFunc child_setup,
63 gint *standard_output,
68 g_spawn_error_quark (void)
70 static GQuark quark = 0;
72 quark = g_quark_from_static_string ("g-exec-error-quark");
78 * @working_directory: child's current working directory, or %NULL to inherit parent's
79 * @argv: child's argument vector
80 * @envp: child's environment, or %NULL to inherit parent's
81 * @flags: flags from #GSpawnFlags
82 * @child_setup: function to run in the child just before <function>exec()</function>
83 * @user_data: user data for @child_setup
84 * @child_pid: return location for child process ID, or %NULL
85 * @error: return location for error
87 * See g_spawn_async_with_pipes() for a full description; this function
88 * simply calls the g_spawn_async_with_pipes() without any pipes.
90 * Return value: %TRUE on success, %FALSE if error is set
93 g_spawn_async (const gchar *working_directory,
97 GSpawnChildSetupFunc child_setup,
102 g_return_val_if_fail (argv != NULL, FALSE);
104 return g_spawn_async_with_pipes (working_directory,
114 /* Avoids a danger in threaded situations (calling close()
115 * on a file descriptor twice, and another thread has
116 * re-opened it since the first close)
119 close_and_invalidate (gint *fd)
136 READ_FAILED = 0, /* FALSE */
142 read_data (GString *str,
151 bytes = read (fd, buf, 4096);
157 g_string_append_len (str, buf, bytes);
160 else if (bytes < 0 && errno == EINTR)
167 _("Failed to read data from child process (%s)"),
178 * @working_directory: child's current working directory, or %NULL to inherit parent's
179 * @argv: child's argument vector
180 * @envp: child's environment, or %NULL to inherit parent's
181 * @flags: flags from #GSpawnFlags
182 * @child_setup: function to run in the child just before <function>exec()</function>
183 * @user_data: user data for @child_setup
184 * @standard_output: return location for child output
185 * @standard_error: return location for child error messages
186 * @exit_status: child exit status, as returned by <function>waitpid()</function>
187 * @error: return location for error
189 * Executes a child synchronously (waits for the child to exit before returning).
190 * All output from the child is stored in @standard_output and @standard_error,
191 * if those parameters are non-%NULL. If @exit_status is non-%NULL, the exit
192 * status of the child is stored there as it would be returned by
193 * <function>waitpid()</function>; standard UNIX macros such as
194 * <function>WIFEXITED()</function> and <function>WEXITSTATUS()</function>
195 * must be used to evaluate the exit status. If an error occurs, no data is
196 * returned in @standard_output, @standard_error, or @exit_status.
198 * This function calls g_spawn_async_with_pipes() internally; see that function
199 * for full details on the other parameters.
201 * Return value: %TRUE on success, %FALSE if an error was set.
204 g_spawn_sync (const gchar *working_directory,
208 GSpawnChildSetupFunc child_setup,
210 gchar **standard_output,
211 gchar **standard_error,
220 GString *outstr = NULL;
221 GString *errstr = NULL;
225 g_return_val_if_fail (argv != NULL, FALSE);
226 g_return_val_if_fail (!(flags & G_SPAWN_DO_NOT_REAP_CHILD), FALSE);
227 g_return_val_if_fail (standard_output == NULL ||
228 !(flags & G_SPAWN_STDOUT_TO_DEV_NULL), FALSE);
229 g_return_val_if_fail (standard_error == NULL ||
230 !(flags & G_SPAWN_STDERR_TO_DEV_NULL), FALSE);
232 /* Just to ensure segfaults if callers try to use
233 * these when an error is reported.
236 *standard_output = NULL;
239 *standard_error = NULL;
241 if (!fork_exec_with_pipes (FALSE,
245 !(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN),
246 (flags & G_SPAWN_SEARCH_PATH) != 0,
247 (flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0,
248 (flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0,
249 (flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0,
250 (flags & G_SPAWN_FILE_AND_ARGV_ZERO) != 0,
255 standard_output ? &outpipe : NULL,
256 standard_error ? &errpipe : NULL,
260 /* Read data from child. */
266 outstr = g_string_new (NULL);
271 errstr = g_string_new (NULL);
274 /* Read data until we get EOF on both pipes. */
283 FD_SET (outpipe, &fds);
285 FD_SET (errpipe, &fds);
287 ret = select (MAX (outpipe, errpipe) + 1,
290 NULL /* no timeout */);
292 if (ret < 0 && errno != EINTR)
299 _("Unexpected error in select() reading data from a child process (%s)"),
305 if (outpipe >= 0 && FD_ISSET (outpipe, &fds))
307 switch (read_data (outstr, outpipe, error))
313 close_and_invalidate (&outpipe);
324 if (errpipe >= 0 && FD_ISSET (errpipe, &fds))
326 switch (read_data (errstr, errpipe, error))
332 close_and_invalidate (&errpipe);
344 /* These should only be open still if we had an error. */
347 close_and_invalidate (&outpipe);
349 close_and_invalidate (&errpipe);
351 /* Wait for child to exit, even if we have
356 ret = waitpid (pid, &status, 0);
362 else if (errno == ECHILD)
366 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.");
370 /* We don't need the exit status. */
375 if (!failed) /* avoid error pileups */
382 _("Unexpected error in waitpid() (%s)"),
391 g_string_free (outstr, TRUE);
393 g_string_free (errstr, TRUE);
400 *exit_status = status;
403 *standard_output = g_string_free (outstr, FALSE);
406 *standard_error = g_string_free (errstr, FALSE);
413 * g_spawn_async_with_pipes:
414 * @working_directory: child's current working directory, or %NULL to inherit parent's
415 * @argv: child's argument vector
416 * @envp: child's environment, or %NULL to inherit parent's
417 * @flags: flags from #GSpawnFlags
418 * @child_setup: function to run in the child just before <function>exec()</function>
419 * @user_data: user data for @child_setup
420 * @child_pid: return location for child process ID, or %NULL
421 * @standard_input: return location for file descriptor to write to child's stdin, or %NULL
422 * @standard_output: return location for file descriptor to read child's stdout, or %NULL
423 * @standard_error: return location for file descriptor to read child's stderr, or %NULL
424 * @error: return location for error
426 * Executes a child program asynchronously (your program will not
427 * block waiting for the child to exit). The child program is
428 * specified by the only argument that must be provided, @argv. @argv
429 * should be a %NULL-terminated array of strings, to be passed as the
430 * argument vector for the child. The first string in @argv is of
431 * course the name of the program to execute. By default, the name of
432 * the program must be a full path; the <envar>PATH</envar> shell variable
433 * will only be searched if you pass the %G_SPAWN_SEARCH_PATH flag.
435 * On Windows, the low-level child process creation API
436 * (<function>CreateProcess()</function>)doesn't use argument vectors,
437 * but a command line. The C runtime library's
438 * <function>spawn*()</function> family of functions (which
439 * g_spawn_async_with_pipes() eventually calls) paste the argument
440 * vector elements into a command line, and the C runtime startup code
441 * does a corresponding recostruction of an argument vector from the
442 * command line, to be passed to
443 * <function>main()</function>. Complications arise when you have
444 * argument vector elements that contain spaces of double quotes. The
445 * <function>spawn()</function> functions don't do any quoting or
446 * escaping, but on the other hand the startup code does do unquoting
447 * and unescaping in order to enable receiving arguments with embedded
448 * spaces or double quotes. To work around this asymmetry,
449 * g_spawn_async_with_pipes() will do quoting and escaping on argument
450 * vector elements that need it before calling the C runtime
451 * <function>spawn()</function> function.
453 * @envp is a %NULL-terminated array of strings, where each string
454 * has the form <literal>KEY=VALUE</literal>. This will become
455 * the child's environment. If @envp is %NULL, the child inherits its
456 * parent's environment.
458 * @flags should be the bitwise OR of any flags you want to affect the
459 * function's behavior. On Unix, the %G_SPAWN_DO_NOT_REAP_CHILD means
460 * that the child will not be automatically reaped; you must call
461 * <function>waitpid()</function> or handle %SIGCHLD yourself, or the
462 * child will become a zombie. On Windows, the flag means that a
463 * handle to the child will be returned @child_pid. You must call
464 * <function>CloseHandle()</function> on it eventually (or exit the
465 * process), or the child processs will continue to take up some table
466 * space even after its death. Quite similar to zombies on Unix,
469 * %G_SPAWN_LEAVE_DESCRIPTORS_OPEN means that the parent's open file
470 * descriptors will be inherited by the child; otherwise all
471 * descriptors except stdin/stdout/stderr will be closed before
472 * calling <function>exec()</function> in the child. %G_SPAWN_SEARCH_PATH
473 * means that <literal>argv[0]</literal> need not be an absolute path, it
474 * will be looked for in the user's <envar>PATH</envar>.
475 * %G_SPAWN_STDOUT_TO_DEV_NULL means that the child's standard output will
476 * be discarded, instead of going to the same location as the parent's
477 * standard output. If you use this flag, @standard_output must be %NULL.
478 * %G_SPAWN_STDERR_TO_DEV_NULL means that the child's standard error
479 * will be discarded, instead of going to the same location as the parent's
480 * standard error. If you use this flag, @standard_error must be %NULL.
481 * %G_SPAWN_CHILD_INHERITS_STDIN means that the child will inherit the parent's
482 * standard input (by default, the child's standard input is attached to
483 * /dev/null). If you use this flag, @standard_input must be %NULL.
484 * %G_SPAWN_FILE_AND_ARGV_ZERO means that the first element of @argv is
485 * the file to execute, while the remaining elements are the
486 * actual argument vector to pass to the file. Normally
487 * g_spawn_async_with_pipes() uses @argv[0] as the file to execute, and
488 * passes all of @argv to the child.
490 * @child_setup and @user_data are a function and user data. On POSIX
491 * platforms, the function is called in the child after GLib has
492 * performed all the setup it plans to perform (including creating
493 * pipes, closing file descriptors, etc.) but before calling
494 * <function>exec()</function>. That is, @child_setup is called just
495 * before calling <function>exec()</function> in the child. Obviously
496 * actions taken in this function will only affect the child, not the
497 * parent. On Windows, there is no separate
498 * <function>fork()</function> and <function>exec()</function>
499 * functionality. Child processes are created and run right away with
500 * one API call, <function>CreateProcess()</function>. @child_setup is
501 * called in the parent process just before creating the child
502 * process. You should carefully consider what you do in @child_setup
503 * if you intend your software to be portable to Windows.
505 * If non-%NULL, @child_pid will on Unix be filled with the child's
506 * process ID. You can use the process ID to send signals to the
507 * child, or to <function>waitpid()</function> if you specified the
508 * %G_SPAWN_DO_NOT_REAP_CHILD flag. On Windows, @child_pid will be
509 * filled with a handle to the child process only if you specified the
510 * %G_SPAWN_DO_NOT_REAP_CHILD flag. You can then access the child
511 * process using the Win32 API, for example wait for its termination
512 * with the <function>WaitFor*()</function> functions, or examine its
513 * exit code with <function>GetExitCodeProcess()</function>. You
514 * should close the handle with <function>CloseHandle()</function>
515 * when you no longer need it.
517 * If non-%NULL, the @standard_input, @standard_output, @standard_error
518 * locations will be filled with file descriptors for writing to the child's
519 * standard input or reading from its standard output or standard error.
520 * The caller of g_spawn_async_with_pipes() must close these file descriptors
521 * when they are no longer in use. If these parameters are %NULL, the corresponding
522 * pipe won't be created.
524 * If @standard_input is NULL, the child's standard input is attached to /dev/null
525 * unless %G_SPAWN_CHILD_INHERITS_STDIN is set.
527 * If @standard_error is NULL, the child's standard error goes to the same location
528 * as the parent's standard error unless %G_SPAWN_STDERR_TO_DEV_NULL is set.
530 * If @standard_output is NULL, the child's standard output goes to the same location
531 * as the parent's standard output unless %G_SPAWN_STDOUT_TO_DEV_NULL is set.
533 * @error can be %NULL to ignore errors, or non-%NULL to report errors.
534 * If an error is set, the function returns %FALSE. Errors
535 * are reported even if they occur in the child (for example if the
536 * executable in <literal>argv[0]</literal> is not found). Typically
537 * the <literal>message</literal> field of returned errors should be displayed
538 * to users. Possible errors are those from the #G_SPAWN_ERROR domain.
540 * If an error occurs, @child_pid, @standard_input, @standard_output,
541 * and @standard_error will not be filled with valid values.
543 * Return value: %TRUE on success, %FALSE if an error was set
546 g_spawn_async_with_pipes (const gchar *working_directory,
550 GSpawnChildSetupFunc child_setup,
553 gint *standard_input,
554 gint *standard_output,
555 gint *standard_error,
558 g_return_val_if_fail (argv != NULL, FALSE);
559 g_return_val_if_fail (standard_output == NULL ||
560 !(flags & G_SPAWN_STDOUT_TO_DEV_NULL), FALSE);
561 g_return_val_if_fail (standard_error == NULL ||
562 !(flags & G_SPAWN_STDERR_TO_DEV_NULL), FALSE);
563 /* can't inherit stdin if we have an input pipe. */
564 g_return_val_if_fail (standard_input == NULL ||
565 !(flags & G_SPAWN_CHILD_INHERITS_STDIN), FALSE);
567 return fork_exec_with_pipes (!(flags & G_SPAWN_DO_NOT_REAP_CHILD),
571 !(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN),
572 (flags & G_SPAWN_SEARCH_PATH) != 0,
573 (flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0,
574 (flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0,
575 (flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0,
576 (flags & G_SPAWN_FILE_AND_ARGV_ZERO) != 0,
587 * g_spawn_command_line_sync:
588 * @command_line: a command line
589 * @standard_output: return location for child output
590 * @standard_error: return location for child errors
591 * @exit_status: return location for child exit status
592 * @error: return location for errors
594 * A simple version of g_spawn_sync() with little-used parameters
595 * removed, taking a command line instead of an argument vector. See
596 * g_spawn_sync() for full details. @command_line will be parsed by
597 * g_shell_parse_argv(). Unlike g_spawn_sync(), the %G_SPAWN_SEARCH_PATH flag
598 * is enabled. Note that %G_SPAWN_SEARCH_PATH can have security
599 * implications, so consider using g_spawn_sync() directly if
600 * appropriate. Possible errors are those from g_spawn_sync() and those
601 * from g_shell_parse_argv().
603 * On Windows, please note the implications of g_shell_parse_argv()
604 * parsing @command_line. Space is a separator, and backslashes are
605 * special. Thus you cannot simply pass a @command_line containing
606 * canonical Windows paths, like "c:\\program files\\app\\app.exe", as
607 * the backslashes will be eaten, and the space will act as a
608 * separator. You need to enclose such paths with single quotes, like
609 * "'c:\\program files\\app\\app.exe' 'e:\\folder\\argument.txt'".
611 * Return value: %TRUE on success, %FALSE if an error was set
614 g_spawn_command_line_sync (const gchar *command_line,
615 gchar **standard_output,
616 gchar **standard_error,
623 g_return_val_if_fail (command_line != NULL, FALSE);
625 if (!g_shell_parse_argv (command_line,
630 retval = g_spawn_sync (NULL,
646 * g_spawn_command_line_async:
647 * @command_line: a command line
648 * @error: return location for errors
650 * A simple version of g_spawn_async() that parses a command line with
651 * g_shell_parse_argv() and passes it to g_spawn_async(). Runs a
652 * command line in the background. Unlike g_spawn_async(), the
653 * %G_SPAWN_SEARCH_PATH flag is enabled, other flags are not. Note
654 * that %G_SPAWN_SEARCH_PATH can have security implications, so
655 * consider using g_spawn_async() directly if appropriate. Possible
656 * errors are those from g_shell_parse_argv() and g_spawn_async().
658 * The same concerns on Windows apply as for g_spawn_command_line_sync().
660 * Return value: %TRUE on success, %FALSE if error is set.
663 g_spawn_command_line_async (const gchar *command_line,
669 g_return_val_if_fail (command_line != NULL, FALSE);
671 if (!g_shell_parse_argv (command_line,
676 retval = g_spawn_async (NULL,
690 exec_err_to_g_error (gint en)
696 return G_SPAWN_ERROR_ACCES;
702 return G_SPAWN_ERROR_PERM;
708 return G_SPAWN_ERROR_2BIG;
714 return G_SPAWN_ERROR_NOEXEC;
720 return G_SPAWN_ERROR_NAMETOOLONG;
726 return G_SPAWN_ERROR_NOENT;
732 return G_SPAWN_ERROR_NOMEM;
738 return G_SPAWN_ERROR_NOTDIR;
744 return G_SPAWN_ERROR_LOOP;
750 return G_SPAWN_ERROR_TXTBUSY;
756 return G_SPAWN_ERROR_IO;
762 return G_SPAWN_ERROR_NFILE;
768 return G_SPAWN_ERROR_MFILE;
774 return G_SPAWN_ERROR_INVAL;
780 return G_SPAWN_ERROR_ISDIR;
786 return G_SPAWN_ERROR_LIBBAD;
791 return G_SPAWN_ERROR_FAILED;
797 write_all (gint fd, gconstpointer vbuf, gsize to_write)
799 gchar *buf = (gchar *) vbuf;
803 gssize count = write (fd, buf, to_write);
820 write_err_and_exit (gint fd, gint msg)
824 write_all (fd, &msg, sizeof(msg));
825 write_all (fd, &en, sizeof(en));
831 set_cloexec (gint fd)
833 fcntl (fd, F_SETFD, FD_CLOEXEC);
837 sane_dup2 (gint fd1, gint fd2)
842 ret = dup2 (fd1, fd2);
843 if (ret < 0 && errno == EINTR)
858 do_exec (gint child_err_report_fd,
862 const gchar *working_directory,
865 gboolean close_descriptors,
866 gboolean search_path,
867 gboolean stdout_to_null,
868 gboolean stderr_to_null,
869 gboolean child_inherits_stdin,
870 gboolean file_and_argv_zero,
871 GSpawnChildSetupFunc child_setup,
874 if (working_directory && chdir (working_directory) < 0)
875 write_err_and_exit (child_err_report_fd,
878 /* Close all file descriptors but stdin stdout and stderr as
879 * soon as we exec. Note that this includes
880 * child_err_report_fd, which keeps the parent from blocking
881 * forever on the other end of that pipe.
883 if (close_descriptors)
888 open_max = sysconf (_SC_OPEN_MAX);
889 for (i = 3; i < open_max; i++)
894 /* We need to do child_err_report_fd anyway */
895 set_cloexec (child_err_report_fd);
898 /* Redirect pipes as required */
902 /* dup2 can't actually fail here I don't think */
904 if (sane_dup2 (stdin_fd, 0) < 0)
905 write_err_and_exit (child_err_report_fd,
908 /* ignore this if it doesn't work */
909 close_and_invalidate (&stdin_fd);
911 else if (!child_inherits_stdin)
913 /* Keep process from blocking on a read of stdin */
914 gint read_null = open ("/dev/null", O_RDONLY);
915 sane_dup2 (read_null, 0);
916 close_and_invalidate (&read_null);
921 /* dup2 can't actually fail here I don't think */
923 if (sane_dup2 (stdout_fd, 1) < 0)
924 write_err_and_exit (child_err_report_fd,
927 /* ignore this if it doesn't work */
928 close_and_invalidate (&stdout_fd);
930 else if (stdout_to_null)
932 gint write_null = open ("/dev/null", O_WRONLY);
933 sane_dup2 (write_null, 1);
934 close_and_invalidate (&write_null);
939 /* dup2 can't actually fail here I don't think */
941 if (sane_dup2 (stderr_fd, 2) < 0)
942 write_err_and_exit (child_err_report_fd,
945 /* ignore this if it doesn't work */
946 close_and_invalidate (&stderr_fd);
948 else if (stderr_to_null)
950 gint write_null = open ("/dev/null", O_WRONLY);
951 sane_dup2 (write_null, 2);
952 close_and_invalidate (&write_null);
955 /* Call user function just before we exec */
958 (* child_setup) (user_data);
962 file_and_argv_zero ? argv + 1 : argv,
966 write_err_and_exit (child_err_report_fd,
983 if (bytes >= sizeof(gint)*2)
984 break; /* give up, who knows what happened, should not be
990 ((gchar*)buf) + bytes,
991 sizeof(gint) * n_ints_in_buf - bytes);
992 if (chunk < 0 && errno == EINTR)
997 /* Some weird shit happened, bail out */
1001 G_SPAWN_ERROR_FAILED,
1002 _("Failed to read from child pipe (%s)"),
1003 g_strerror (errno));
1007 else if (chunk == 0)
1009 else /* chunk > 0 */
1013 *n_ints_read = (gint)(bytes / sizeof(gint));
1019 fork_exec_with_pipes (gboolean intermediate_child,
1020 const gchar *working_directory,
1023 gboolean close_descriptors,
1024 gboolean search_path,
1025 gboolean stdout_to_null,
1026 gboolean stderr_to_null,
1027 gboolean child_inherits_stdin,
1028 gboolean file_and_argv_zero,
1029 GSpawnChildSetupFunc child_setup,
1032 gint *standard_input,
1033 gint *standard_output,
1034 gint *standard_error,
1038 gint stdin_pipe[2] = { -1, -1 };
1039 gint stdout_pipe[2] = { -1, -1 };
1040 gint stderr_pipe[2] = { -1, -1 };
1041 gint child_err_report_pipe[2] = { -1, -1 };
1042 gint child_pid_report_pipe[2] = { -1, -1 };
1045 if (!make_pipe (child_err_report_pipe, error))
1048 if (intermediate_child && !make_pipe (child_pid_report_pipe, error))
1049 goto cleanup_and_fail;
1051 if (standard_input && !make_pipe (stdin_pipe, error))
1052 goto cleanup_and_fail;
1054 if (standard_output && !make_pipe (stdout_pipe, error))
1055 goto cleanup_and_fail;
1057 if (standard_error && !make_pipe (stderr_pipe, error))
1058 goto cleanup_and_fail;
1067 _("Failed to fork (%s)"),
1068 g_strerror (errno));
1070 goto cleanup_and_fail;
1074 /* Immediate child. This may or may not be the child that
1075 * actually execs the new process.
1078 /* Be sure we crash if the parent exits
1079 * and we write to the err_report_pipe
1081 signal (SIGPIPE, SIG_DFL);
1083 /* Close the parent's end of the pipes;
1084 * not needed in the close_descriptors case,
1087 close_and_invalidate (&child_err_report_pipe[0]);
1088 close_and_invalidate (&child_pid_report_pipe[0]);
1089 close_and_invalidate (&stdin_pipe[1]);
1090 close_and_invalidate (&stdout_pipe[0]);
1091 close_and_invalidate (&stderr_pipe[0]);
1093 if (intermediate_child)
1095 /* We need to fork an intermediate child that launches the
1096 * final child. The purpose of the intermediate child
1097 * is to exit, so we can waitpid() it immediately.
1098 * Then the grandchild will not become a zombie.
1100 gint grandchild_pid;
1102 grandchild_pid = fork ();
1104 if (grandchild_pid < 0)
1106 /* report -1 as child PID */
1107 write_all (child_pid_report_pipe[1], &grandchild_pid,
1108 sizeof(grandchild_pid));
1110 write_err_and_exit (child_err_report_pipe[1],
1113 else if (grandchild_pid == 0)
1115 do_exec (child_err_report_pipe[1],
1126 child_inherits_stdin,
1133 write_all (child_pid_report_pipe[1], &grandchild_pid, sizeof(grandchild_pid));
1134 close_and_invalidate (&child_pid_report_pipe[1]);
1141 /* Just run the child.
1144 do_exec (child_err_report_pipe[1],
1155 child_inherits_stdin,
1168 /* Close the uncared-about ends of the pipes */
1169 close_and_invalidate (&child_err_report_pipe[1]);
1170 close_and_invalidate (&child_pid_report_pipe[1]);
1171 close_and_invalidate (&stdin_pipe[0]);
1172 close_and_invalidate (&stdout_pipe[1]);
1173 close_and_invalidate (&stderr_pipe[1]);
1175 /* If we had an intermediate child, reap it */
1176 if (intermediate_child)
1179 if (waitpid (pid, &status, 0) < 0)
1183 else if (errno == ECHILD)
1184 ; /* do nothing, child already reaped */
1186 g_warning ("waitpid() should not fail in "
1187 "'fork_exec_with_pipes'");
1192 if (!read_ints (child_err_report_pipe[0],
1195 goto cleanup_and_fail;
1199 /* Error from the child. */
1203 case CHILD_CHDIR_FAILED:
1206 G_SPAWN_ERROR_CHDIR,
1207 _("Failed to change to directory '%s' (%s)"),
1209 g_strerror (buf[1]));
1213 case CHILD_EXEC_FAILED:
1216 exec_err_to_g_error (buf[1]),
1217 _("Failed to execute child process \"%s\" (%s)"),
1219 g_strerror (buf[1]));
1223 case CHILD_DUP2_FAILED:
1226 G_SPAWN_ERROR_FAILED,
1227 _("Failed to redirect output or input of child process (%s)"),
1228 g_strerror (buf[1]));
1232 case CHILD_FORK_FAILED:
1236 _("Failed to fork child process (%s)"),
1237 g_strerror (buf[1]));
1243 G_SPAWN_ERROR_FAILED,
1244 _("Unknown error executing child process \"%s\""),
1249 goto cleanup_and_fail;
1252 /* Get child pid from intermediate child pipe. */
1253 if (intermediate_child)
1257 if (!read_ints (child_pid_report_pipe[0],
1258 buf, 1, &n_ints, error))
1259 goto cleanup_and_fail;
1265 G_SPAWN_ERROR_FAILED,
1266 _("Failed to read enough data from child pid pipe (%s)"),
1267 g_strerror (errno));
1268 goto cleanup_and_fail;
1272 /* we have the child pid */
1277 /* Success against all odds! return the information */
1278 close_and_invalidate (&child_err_report_pipe[0]);
1279 close_and_invalidate (&child_pid_report_pipe[0]);
1285 *standard_input = stdin_pipe[1];
1286 if (standard_output)
1287 *standard_output = stdout_pipe[0];
1289 *standard_error = stderr_pipe[0];
1296 /* There was an error from the Child, reap the child to avoid it being
1303 if (waitpid (pid, NULL, 0) < 0)
1307 else if (errno == ECHILD)
1308 ; /* do nothing, child already reaped */
1310 g_warning ("waitpid() should not fail in "
1311 "'fork_exec_with_pipes'");
1315 close_and_invalidate (&child_err_report_pipe[0]);
1316 close_and_invalidate (&child_err_report_pipe[1]);
1317 close_and_invalidate (&child_pid_report_pipe[0]);
1318 close_and_invalidate (&child_pid_report_pipe[1]);
1319 close_and_invalidate (&stdin_pipe[0]);
1320 close_and_invalidate (&stdin_pipe[1]);
1321 close_and_invalidate (&stdout_pipe[0]);
1322 close_and_invalidate (&stdout_pipe[1]);
1323 close_and_invalidate (&stderr_pipe[0]);
1324 close_and_invalidate (&stderr_pipe[1]);
1330 make_pipe (gint p[2],
1337 G_SPAWN_ERROR_FAILED,
1338 _("Failed to create pipe for communicating with child process (%s)"),
1339 g_strerror (errno));
1346 /* Based on execvp from GNU C Library */
1349 script_execute (const gchar *file,
1352 gboolean search_path)
1354 /* Count the arguments. */
1359 /* Construct an argument list for the shell. */
1363 new_argv = g_new0 (gchar*, argc + 2); /* /bin/sh and NULL */
1365 new_argv[0] = (char *) "/bin/sh";
1366 new_argv[1] = (char *) file;
1369 new_argv[argc + 1] = argv[argc];
1373 /* Execute the shell. */
1375 execve (new_argv[0], new_argv, envp);
1377 execv (new_argv[0], new_argv);
1384 my_strchrnul (const gchar *str, gchar c)
1386 gchar *p = (gchar*) str;
1387 while (*p && (*p != c))
1394 g_execute (const gchar *file,
1397 gboolean search_path)
1401 /* We check the simple case first. */
1406 if (!search_path || strchr (file, '/') != NULL)
1408 /* Don't search when it contains a slash. */
1410 execve (file, argv, envp);
1414 if (errno == ENOEXEC)
1415 script_execute (file, argv, envp, FALSE);
1419 gboolean got_eacces = 0;
1420 const gchar *path, *p;
1421 gchar *name, *freeme;
1425 path = g_getenv ("PATH");
1428 /* There is no `PATH' in the environment. The default
1429 * search path in libc is the current directory followed by
1430 * the path `confstr' returns for `_CS_PATH'.
1433 /* In GLib we put . last, for security, and don't use the
1434 * unportable confstr(); UNIX98 does not actually specify
1435 * what to search if PATH is unset. POSIX may, dunno.
1438 path = "/bin:/usr/bin:.";
1441 len = strlen (file) + 1;
1442 pathlen = strlen (path);
1443 freeme = name = g_malloc (pathlen + len + 1);
1445 /* Copy the file name at the top, including '\0' */
1446 memcpy (name + pathlen + 1, file, len);
1447 name = name + pathlen;
1448 /* And add the slash before the filename */
1457 p = my_strchrnul (path, ':');
1460 /* Two adjacent colons, or a colon at the beginning or the end
1461 * of `PATH' means to search the current directory.
1465 startp = memcpy (name - (p - path), path, p - path);
1467 /* Try to execute this name. If it works, execv will not return. */
1469 execve (startp, argv, envp);
1471 execv (startp, argv);
1473 if (errno == ENOEXEC)
1474 script_execute (startp, argv, envp, search_path);
1479 /* Record the we got a `Permission denied' error. If we end
1480 * up finding no executable we can use, we want to diagnose
1481 * that we did find one but were denied access.
1494 /* Those errors indicate the file is missing or not executable
1495 * by us, in which case we want to just try the next path
1501 /* Some other error means we found an executable file, but
1502 * something went wrong executing it; return the error to our
1509 while (*p++ != '\0');
1511 /* We tried every element and none of them worked. */
1513 /* At least one failure was due to permissions, so report that
1521 /* Return the error from the last attempt (probably ENOENT). */