1 /* GIO - GLib Input, Output and Streaming Library
3 * Copyright © 2012 Red Hat, Inc.
4 * Copyright © 2012-2013 Canonical Limited
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU Lesser General Public License as published
8 * by the Free Software Foundation; either version 2 of the licence or (at
9 * your option) any later version.
11 * See the included COPYING file for more information.
13 * Authors: Colin Walters <walters@verbum.org>
14 * Ryan Lortie <desrt@desrt.ca>
18 * SECTION:gsubprocesslauncher
19 * @title: GSubprocess Launcher
20 * @short_description: Environment options for launching a child process
23 * This class contains a set of options for launching child processes,
24 * such as where its standard input and output will be directed, the
25 * argument list, the environment, and more.
27 * While the #GSubprocess class has high level functions covering
28 * popular cases, use of this class allows access to more advanced
29 * options. It can also be used to launch multiple subprocesses with
30 * a similar configuration.
35 #define ALL_STDIN_FLAGS (G_SUBPROCESS_FLAGS_STDIN_PIPE | \
36 G_SUBPROCESS_FLAGS_STDIN_INHERIT)
37 #define ALL_STDOUT_FLAGS (G_SUBPROCESS_FLAGS_STDOUT_PIPE | \
38 G_SUBPROCESS_FLAGS_STDOUT_SILENCE)
39 #define ALL_STDERR_FLAGS (G_SUBPROCESS_FLAGS_STDERR_PIPE | \
40 G_SUBPROCESS_FLAGS_STDERR_SILENCE | \
41 G_SUBPROCESS_FLAGS_STDERR_MERGE)
45 #include "gsubprocesslauncher-private.h"
46 #include "gioenumtypes.h"
47 #include "gsubprocess.h"
48 #include "ginitable.h"
55 typedef GObjectClass GSubprocessLauncherClass;
57 G_DEFINE_TYPE (GSubprocessLauncher, g_subprocess_launcher, G_TYPE_OBJECT);
60 verify_disposition (const gchar *stream_name,
61 GSubprocessFlags filtered_flags,
63 const gchar *filename)
69 else if (((filtered_flags - 1) & filtered_flags) == 0)
72 n_bits = 2; /* ...or more */
74 if (n_bits + (fd >= 0) + (filename != NULL) > 1)
78 err = g_string_new (NULL);
84 class = g_type_class_peek (G_TYPE_SUBPROCESS_FLAGS);
85 while ((value = g_flags_get_first_value (class, filtered_flags)))
87 g_string_append_printf (err, " %s", value->value_name);
88 filtered_flags &= value->value;
91 g_type_class_unref (class);
95 g_string_append_printf (err, " g_subprocess_launcher_take_%s_fd()", stream_name);
98 g_string_append_printf (err, " g_subprocess_launcher_set_%s_file_path()", stream_name);
100 g_critical ("You may specify at most one disposition for the %s stream, but you specified:%s.",
101 stream_name, err->str);
102 g_string_free (err, TRUE);
111 verify_flags (GSubprocessFlags flags)
113 return verify_disposition ("stdin", flags & ALL_STDIN_FLAGS, -1, NULL) &&
114 verify_disposition ("stdout", flags & ALL_STDOUT_FLAGS, -1, NULL) &&
115 verify_disposition ("stderr", flags & ALL_STDERR_FLAGS, -1, NULL);
119 g_subprocess_launcher_set_property (GObject *object, guint prop_id,
120 const GValue *value, GParamSpec *pspec)
122 GSubprocessLauncher *launcher = G_SUBPROCESS_LAUNCHER (object);
124 g_assert (prop_id == 1);
126 if (verify_flags (g_value_get_flags (value)))
127 launcher->flags = g_value_get_flags (value);
131 g_subprocess_launcher_finalize (GObject *object)
133 GSubprocessLauncher *self = G_SUBPROCESS_LAUNCHER (object);
138 g_free (self->stdin_path);
139 g_free (self->stdout_path);
140 g_free (self->stderr_path);
142 if (self->stdin_fd != -1)
143 close (self->stdin_fd);
145 if (self->stdout_fd != -1)
146 close (self->stdout_fd);
148 if (self->stderr_fd != -1)
149 close (self->stderr_fd);
151 if (self->basic_fd_assignments)
153 for (i = 0; i < self->basic_fd_assignments->len; i++)
154 (void) close (g_array_index (self->basic_fd_assignments, int, i));
155 g_array_unref (self->basic_fd_assignments);
157 if (self->needdup_fd_assignments)
159 for (i = 0; i < self->needdup_fd_assignments->len; i += 2)
160 (void) close (g_array_index (self->needdup_fd_assignments, int, i));
161 g_array_unref (self->needdup_fd_assignments);
164 if (self->child_setup_destroy_notify)
165 (* self->child_setup_destroy_notify) (self->child_setup_user_data);
168 g_strfreev (self->envp);
171 G_OBJECT_CLASS (g_subprocess_launcher_parent_class)->finalize (object);
175 g_subprocess_launcher_init (GSubprocessLauncher *self)
177 self->envp = g_get_environ ();
181 self->stdout_fd = -1;
182 self->stderr_fd = -1;
183 self->basic_fd_assignments = g_array_new (FALSE, 0, sizeof (int));
184 self->needdup_fd_assignments = g_array_new (FALSE, 0, sizeof (int));
189 g_subprocess_launcher_class_init (GSubprocessLauncherClass *class)
191 GObjectClass *gobject_class = G_OBJECT_CLASS (class);
193 gobject_class->set_property = g_subprocess_launcher_set_property;
194 gobject_class->finalize = g_subprocess_launcher_finalize;
196 g_object_class_install_property (gobject_class, 1,
197 g_param_spec_flags ("flags", "Flags", "GSubprocessFlags for launched processes",
198 G_TYPE_SUBPROCESS_FLAGS, 0, G_PARAM_WRITABLE |
199 G_PARAM_STATIC_STRINGS | G_PARAM_CONSTRUCT_ONLY));
203 * g_subprocess_launcher_new:
204 * @flags: #GSubprocessFlags
206 * Creates a new #GSubprocessLauncher.
208 * The launcher is created with the default options. A copy of the
209 * environment of the calling process is made at the time of this call
210 * and will be used as the environment that the process is launched in.
214 GSubprocessLauncher *
215 g_subprocess_launcher_new (GSubprocessFlags flags)
217 if (!verify_flags (flags))
220 return g_object_new (G_TYPE_SUBPROCESS_LAUNCHER,
226 * g_subprocess_launcher_set_environ:
227 * @self: a #GSubprocess
228 * @env: the replacement environment
230 * Replace the entire environment of processes launched from this
231 * launcher with the given 'environ' variable.
233 * Typically you will build this variable by using g_listenv() to copy
234 * the process 'environ' and using the functions g_environ_setenv(),
235 * g_environ_unsetenv(), etc.
237 * As an alternative, you can use g_subprocess_launcher_setenv(),
238 * g_subprocess_launcher_unsetenv(), etc.
240 * All strings in this array are expected to be in the GLib file name
241 * encoding. On UNIX, this means that they can be arbitrary byte
242 * strings. On Windows, they should be in UTF-8.
247 g_subprocess_launcher_set_environ (GSubprocessLauncher *self,
250 g_strfreev (self->envp);
251 self->envp = g_strdupv (env);
255 * g_subprocess_launcher_setenv:
256 * @self: a #GSubprocess
257 * @variable: the environment variable to set, must not contain '='
258 * @value: the new value for the variable
259 * @overwrite: whether to change the variable if it already exists
261 * Sets the environment variable @variable in the environment of
262 * processes launched from this launcher.
264 * Both the variable's name and value should be in the GLib file name
265 * encoding. On UNIX, this means that they can be arbitrary byte
266 * strings. On Windows, they should be in UTF-8.
272 g_subprocess_launcher_setenv (GSubprocessLauncher *self,
273 const gchar *variable,
277 self->envp = g_environ_setenv (self->envp, variable, value, overwrite);
281 * g_subprocess_launcher_unsetenv:
282 * @self: a #GSubprocess
283 * @variable: the environment variable to unset, must not contain '='
285 * Removes the environment variable @variable from the environment of
286 * processes launched from this launcher.
288 * The variable name should be in the GLib file name encoding. On UNIX,
289 * this means that they can be arbitrary byte strings. On Windows, they
290 * should be in UTF-8.
295 g_subprocess_launcher_unsetenv (GSubprocessLauncher *self,
296 const gchar *variable)
298 self->envp = g_environ_unsetenv (self->envp, variable);
302 * g_subprocess_launcher_getenv:
303 * @self: a #GSubprocess
304 * @variable: the environment variable to get
306 * Returns the value of the environment variable @variable in the
307 * environment of processes launched from this launcher.
309 * The returned string is in the GLib file name encoding. On UNIX, this
310 * means that it can be an arbitrary byte string. On Windows, it will
313 * Returns: the value of the environment variable, %NULL if unset
318 g_subprocess_launcher_getenv (GSubprocessLauncher *self,
319 const gchar *variable)
321 return g_environ_getenv (self->envp, variable);
325 * g_subprocess_launcher_set_cwd:
326 * @self: a #GSubprocess
327 * @cwd: the cwd for launched processes
329 * Sets the current working directory that processes will be launched
332 * By default processes are launched with the current working directory
333 * of the launching process at the time of launch.
338 g_subprocess_launcher_set_cwd (GSubprocessLauncher *self,
342 self->cwd = g_strdup (cwd);
346 * g_subprocess_launcher_set_flags:
347 * @self: a #GSubprocessLauncher
348 * @flags: #GSubprocessFlags
350 * Sets the flags on the launcher.
352 * The default flags are %G_SUBPROCESS_FLAGS_NONE.
354 * You may not set flags that specify conflicting options for how to
355 * handle a particular stdio stream (eg: specifying both
356 * %G_SUBPROCESS_FLAGS_STDIN_PIPE and
357 * %G_SUBPROCESS_FLAGS_STDIN_INHERIT).
359 * You may also not set a flag that conflicts with a previous call to a
360 * function like g_subprocess_launcher_set_stdin_file_path() or
361 * g_subprocess_launcher_take_stdout_fd().
366 g_subprocess_launcher_set_flags (GSubprocessLauncher *self,
367 GSubprocessFlags flags)
369 const gchar *stdin_path = NULL, *stdout_path = NULL, *stderr_path = NULL;
370 gint stdin_fd = -1, stdout_fd = -1, stderr_fd = -1;
373 stdin_fd = self->stdin_fd;
374 stdout_fd = self->stdout_fd;
375 stderr_fd = self->stderr_fd;
376 stdin_path = self->stdin_path;
377 stdout_path = self->stdout_path;
378 stderr_path = self->stderr_path;
381 if (verify_disposition ("stdin", flags & ALL_STDIN_FLAGS, stdin_fd, stdin_path) &&
382 verify_disposition ("stdout", flags & ALL_STDOUT_FLAGS, stdout_fd, stdout_path) &&
383 verify_disposition ("stderr", flags & ALL_STDERR_FLAGS, stderr_fd, stderr_path))
389 assign_fd (gint *fd_ptr, gint fd)
401 flags = fcntl (fd, F_GETFD);
402 if (~flags & FD_CLOEXEC)
403 fcntl (fd, F_SETFD, flags | FD_CLOEXEC);
408 * g_subprocess_launcher_set_stdin_file_path:
409 * @self: a #GSubprocessLauncher
410 * @path: a filename or %NULL
412 * Sets the file path to use as the stdin for spawned processes.
414 * If @path is %NULL then any previously given path is unset.
416 * The file must exist or spawning the process will fail.
418 * You may not set a stdin file path if a stdin fd is already set or if
419 * the launcher flags contain any flags directing stdin elsewhere.
421 * This feature is only available on UNIX.
426 g_subprocess_launcher_set_stdin_file_path (GSubprocessLauncher *self,
429 if (verify_disposition ("stdin", self->flags & ALL_STDIN_FLAGS, self->stdin_fd, path))
431 g_free (self->stdin_path);
432 self->stdin_path = g_strdup (path);
437 * g_subprocess_launcher_take_stdin_fd:
438 * @self: a #GSubprocessLauncher
439 * @fd: a file descriptor, or -1
441 * Sets the file descriptor to use as the stdin for spawned processes.
443 * If @fd is -1 then any previously given fd is unset.
445 * Note that if your intention is to have the stdin of the calling
446 * process inherited by the child then %G_SUBPROCESS_FLAGS_STDIN_INHERIT
447 * is a better way to go about doing that.
449 * The passed @fd is noted but will not be touched in the current
450 * process. It is therefore necessary that it be kept open by the
451 * caller until the subprocess is spawned. The file descriptor will
452 * also not be explicitly closed on the child side, so it must be marked
453 * O_CLOEXEC if that's what you want.
455 * You may not set a stdin fd if a stdin file path is already set or if
456 * the launcher flags contain any flags directing stdin elsewhere.
458 * This feature is only available on UNIX.
463 g_subprocess_launcher_take_stdin_fd (GSubprocessLauncher *self,
466 if (verify_disposition ("stdin", self->flags & ALL_STDIN_FLAGS, fd, self->stdin_path))
467 assign_fd (&self->stdin_fd, fd);
471 * g_subprocess_launcher_set_stdout_file_path:
472 * @self: a #GSubprocessLauncher
473 * @path: a filename or %NULL
475 * Sets the file path to use as the stdout for spawned processes.
477 * If @path is %NULL then any previously given path is unset.
479 * The file will be created or truncated when the process is spawned, as
480 * would be the case if using '>' at the shell.
482 * You may not set a stdout file path if a stdout fd is already set or
483 * if the launcher flags contain any flags directing stdout elsewhere.
485 * This feature is only available on UNIX.
490 g_subprocess_launcher_set_stdout_file_path (GSubprocessLauncher *self,
493 if (verify_disposition ("stdout", self->flags & ALL_STDOUT_FLAGS, self->stdout_fd, path))
495 g_free (self->stdout_path);
496 self->stdout_path = g_strdup (path);
501 * g_subprocess_launcher_take_stdout_fd:
502 * @self: a #GSubprocessLauncher
503 * @fd: a file descriptor, or -1
505 * Sets the file descriptor to use as the stdout for spawned processes.
507 * If @fd is -1 then any previously given fd is unset.
509 * Note that the default behaviour is to pass stdout through to the
510 * stdout of the parent process.
512 * The passed @fd is noted but will not be touched in the current
513 * process. It is therefore necessary that it be kept open by the
514 * caller until the subprocess is spawned. The file descriptor will
515 * also not be explicitly closed on the child side, so it must be marked
516 * O_CLOEXEC if that's what you want.
518 * You may not set a stdout fd if a stdout file path is already set or
519 * if the launcher flags contain any flags directing stdout elsewhere.
521 * This feature is only available on UNIX.
526 g_subprocess_launcher_take_stdout_fd (GSubprocessLauncher *self,
529 if (verify_disposition ("stdout", self->flags & ALL_STDOUT_FLAGS, fd, self->stdout_path))
530 assign_fd (&self->stdout_fd, fd);
534 * g_subprocess_launcher_set_stderr_file_path:
535 * @self: a #GSubprocessLauncher
536 * @path: a filename or %NULL
538 * Sets the file path to use as the stderr for spawned processes.
540 * If @path is %NULL then any previously given path is unset.
542 * The file will be created or truncated when the process is spawned, as
543 * would be the case if using '2>' at the shell.
545 * If you want to send both stdout and stderr to the same file then use
546 * %G_SUBPROCESS_FLAGS_STDERR_MERGE.
548 * You may not set a stderr file path if a stderr fd is already set or
549 * if the launcher flags contain any flags directing stderr elsewhere.
551 * This feature is only available on UNIX.
556 g_subprocess_launcher_set_stderr_file_path (GSubprocessLauncher *self,
559 if (verify_disposition ("stderr", self->flags & ALL_STDERR_FLAGS, self->stderr_fd, path))
561 g_free (self->stderr_path);
562 self->stderr_path = g_strdup (path);
567 * g_subprocess_launcher_take_stderr_fd:
568 * @self: a #GSubprocessLauncher
569 * @fd: a file descriptor, or -1
571 * Sets the file descriptor to use as the stderr for spawned processes.
573 * If @fd is -1 then any previously given fd is unset.
575 * Note that the default behaviour is to pass stderr through to the
576 * stderr of the parent process.
578 * The passed @fd belongs to the #GSubprocessLauncher. It will be
579 * automatically closed when the launcher is finalized. The file
580 * descriptor will also be closed on the child side when executing the
583 * You may not set a stderr fd if a stderr file path is already set or
584 * if the launcher flags contain any flags directing stderr elsewhere.
586 * This feature is only available on UNIX.
591 g_subprocess_launcher_take_stderr_fd (GSubprocessLauncher *self,
594 if (verify_disposition ("stderr", self->flags & ALL_STDERR_FLAGS, fd, self->stderr_path))
595 assign_fd (&self->stderr_fd, fd);
599 * g_subprocess_launcher_take_fd:
600 * @self: a #GSubprocessLauncher
601 * @source_fd: File descriptor in parent process
602 * @target_fd: Target descriptor for child process
604 * Transfer an arbitrary file descriptor from parent process to the
605 * child. This function takes "ownership" of the fd; it will be closed
606 * in the parent when @self is freed.
608 * By default, all file descriptors from the parent will be closed.
609 * This function allows you to create (for example) a custom pipe() or
610 * socketpair() before launching the process, and choose the target
611 * descriptor in the child.
613 * An example use case is GNUPG, which has a command line argument
614 * --passphrase-fd providing a file descriptor number where it expects
615 * the passphrase to be written.
618 g_subprocess_launcher_take_fd (GSubprocessLauncher *self,
622 if (source_fd == target_fd)
624 g_array_append_val (self->basic_fd_assignments, source_fd);
628 g_array_append_val (self->needdup_fd_assignments, source_fd);
629 g_array_append_val (self->needdup_fd_assignments, target_fd);
634 * g_subprocess_launcher_set_child_setup:
635 * @self: a #GSubprocessLauncher
636 * @child_setup: a #GSpawnChildSetupFunc to use as the child setup function
637 * @user_data: user data for @child_setup
638 * @destroy_notify: a #GDestroyNotify for @user_data
640 * Sets up a child setup function.
642 * The child setup function will be called after fork() but before
643 * exec() on the child's side.
645 * @destroy_notify will not be automatically called on the child's side
646 * of the fork(). It will only be called when the last reference on the
647 * #GSubprocessLauncher is dropped or when a new child setup function is
650 * %NULL can be given as @child_setup to disable the functionality.
652 * Child setup functions are only available on UNIX.
657 g_subprocess_launcher_set_child_setup (GSubprocessLauncher *self,
658 GSpawnChildSetupFunc child_setup,
660 GDestroyNotify destroy_notify)
662 if (self->child_setup_destroy_notify)
663 (* self->child_setup_destroy_notify) (self->child_setup_user_data);
665 self->child_setup_func = child_setup;
666 self->child_setup_user_data = user_data;
667 self->child_setup_destroy_notify = destroy_notify;
672 * g_subprocess_launcher_spawn:
673 * @self: a #GSubprocessLauncher
675 * @argv0: Command line arguments
676 * @...: Continued arguments, %NULL terminated
678 * A convenience helper for creating a #GSubprocess given a provided
679 * varargs list of arguments.
682 * Returns: (transfer full): A new #GSubprocess, or %NULL on error (and @error will be set)
685 g_subprocess_launcher_spawn (GSubprocessLauncher *launcher,
695 g_return_val_if_fail (argv0 != NULL && argv0[0] != '\0', NULL);
696 g_return_val_if_fail (error == NULL || *error == NULL, NULL);
698 args = g_ptr_array_new ();
700 va_start (ap, argv0);
701 g_ptr_array_add (args, (gchar *) argv0);
702 while ((arg = va_arg (ap, const gchar *)))
703 g_ptr_array_add (args, (gchar *) arg);
705 g_ptr_array_add (args, NULL);
708 result = g_subprocess_launcher_spawnv (launcher, (const gchar * const *) args->pdata, error);
710 g_ptr_array_free (args, TRUE);
717 * g_subprocess_launcher_spawnv:
718 * @self: a #GSubprocessLauncher
719 * @argv: (array zero-terminated=1) (element-type utf8): Command line arguments
722 * A convenience helper for creating a #GSubprocess given a provided
723 * array of arguments.
726 * Returns: (transfer full): A new #GSubprocess, or %NULL on error (and @error will be set)
729 g_subprocess_launcher_spawnv (GSubprocessLauncher *launcher,
730 const gchar * const *argv,
733 GSubprocess *subprocess;
735 g_return_val_if_fail (argv != NULL && argv[0] != NULL && argv[0][0] != '\0', NULL);
737 subprocess = g_object_new (G_TYPE_SUBPROCESS,
739 "flags", launcher->flags,
741 g_subprocess_set_launcher (subprocess, launcher);
743 if (!g_initable_init (G_INITABLE (subprocess), NULL, error))
745 g_object_unref (subprocess);