1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * gmain.c: Main loop abstraction, timeouts, and idle functions
5 * Copyright 1998 Owen Taylor
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library 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 this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
24 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
25 * file for a list of people on the GLib Team. See the ChangeLog
26 * files for a list of changes. These files are distributed with
27 * GLib at ftp://ftp.gtk.org/pub/gtk/.
35 #include "glibconfig.h"
37 /* Uncomment the next line (and the corresponding line in gpoll.c) to
38 * enable debugging printouts if the environment variable
39 * G_MAIN_POLL_DEBUG is set to some value.
41 /* #define G_MAIN_POLL_DEBUG */
44 /* Always enable debugging printout on Windows, as it is more often
47 #define G_MAIN_POLL_DEBUG
51 #include "glib-unix.h"
53 #include <sys/eventfd.h>
58 #include <sys/types.h>
61 #ifdef HAVE_SYS_TIME_H
63 #endif /* HAVE_SYS_TIME_H */
66 #endif /* HAVE_UNISTD_H */
73 #endif /* G_OS_WIN32 */
76 #include <sys/socket.h>
78 #endif /* G_OS_BEOS */
83 #include "giochannel.h"
87 #include "gstrfuncs.h"
88 #include "gtestutils.h"
89 #include "gthreadprivate.h"
95 #ifdef G_MAIN_POLL_DEBUG
101 #include "glibprivate.h"
105 * @title: The Main Event Loop
106 * @short_description: manages all available sources of events
108 * The main event loop manages all the available sources of events for
109 * GLib and GTK+ applications. These events can come from any number of
110 * different types of sources such as file descriptors (plain files,
111 * pipes or sockets) and timeouts. New types of event sources can also
112 * be added using g_source_attach().
114 * To allow multiple independent sets of sources to be handled in
115 * different threads, each source is associated with a #GMainContext.
116 * A GMainContext can only be running in a single thread, but
117 * sources can be added to it and removed from it from other threads.
119 * Each event source is assigned a priority. The default priority,
120 * #G_PRIORITY_DEFAULT, is 0. Values less than 0 denote higher priorities.
121 * Values greater than 0 denote lower priorities. Events from high priority
122 * sources are always processed before events from lower priority sources.
124 * Idle functions can also be added, and assigned a priority. These will
125 * be run whenever no events with a higher priority are ready to be processed.
127 * The #GMainLoop data type represents a main event loop. A GMainLoop is
128 * created with g_main_loop_new(). After adding the initial event sources,
129 * g_main_loop_run() is called. This continuously checks for new events from
130 * each of the event sources and dispatches them. Finally, the processing of
131 * an event from one of the sources leads to a call to g_main_loop_quit() to
132 * exit the main loop, and g_main_loop_run() returns.
134 * It is possible to create new instances of #GMainLoop recursively.
135 * This is often used in GTK+ applications when showing modal dialog
136 * boxes. Note that event sources are associated with a particular
137 * #GMainContext, and will be checked and dispatched for all main
138 * loops associated with that GMainContext.
140 * GTK+ contains wrappers of some of these functions, e.g. gtk_main(),
141 * gtk_main_quit() and gtk_events_pending().
143 * <refsect2><title>Creating new source types</title>
144 * <para>One of the unusual features of the #GMainLoop functionality
145 * is that new types of event source can be created and used in
146 * addition to the builtin type of event source. A new event source
147 * type is used for handling GDK events. A new source type is created
148 * by <firstterm>deriving</firstterm> from the #GSource structure.
149 * The derived type of source is represented by a structure that has
150 * the #GSource structure as a first element, and other elements specific
151 * to the new source type. To create an instance of the new source type,
152 * call g_source_new() passing in the size of the derived structure and
153 * a table of functions. These #GSourceFuncs determine the behavior of
154 * the new source type.</para>
155 * <para>New source types basically interact with the main context
156 * in two ways. Their prepare function in #GSourceFuncs can set a timeout
157 * to determine the maximum amount of time that the main loop will sleep
158 * before checking the source again. In addition, or as well, the source
159 * can add file descriptors to the set that the main context checks using
160 * g_source_add_poll().</para>
162 * <refsect2><title>Customizing the main loop iteration</title>
163 * <para>Single iterations of a #GMainContext can be run with
164 * g_main_context_iteration(). In some cases, more detailed control
165 * of exactly how the details of the main loop work is desired, for
166 * instance, when integrating the #GMainLoop with an external main loop.
167 * In such cases, you can call the component functions of
168 * g_main_context_iteration() directly. These functions are
169 * g_main_context_prepare(), g_main_context_query(),
170 * g_main_context_check() and g_main_context_dispatch().</para>
171 * <para>The operation of these functions can best be seen in terms
172 * of a state diagram, as shown in <xref linkend="mainloop-states"/>.</para>
173 * <figure id="mainloop-states"><title>States of a Main Context</title>
174 * <graphic fileref="mainloop-states.gif" format="GIF"></graphic>
181 typedef struct _GTimeoutSource GTimeoutSource;
182 typedef struct _GChildWatchSource GChildWatchSource;
183 typedef struct _GUnixSignalWatchSource GUnixSignalWatchSource;
184 typedef struct _GPollRec GPollRec;
185 typedef struct _GSourceCallback GSourceCallback;
189 G_SOURCE_READY = 1 << G_HOOK_FLAG_USER_SHIFT,
190 G_SOURCE_CAN_RECURSE = 1 << (G_HOOK_FLAG_USER_SHIFT + 1)
193 typedef struct _GMainWaiter GMainWaiter;
201 typedef struct _GMainDispatch GMainDispatch;
203 struct _GMainDispatch
206 GSList *dispatching_sources; /* stack of current sources */
209 #ifdef G_MAIN_POLL_DEBUG
210 gboolean _g_main_poll_debug = FALSE;
215 /* The following lock is used for both the list of sources
216 * and the list of poll records
226 GPtrArray *pending_dispatches;
227 gint timeout; /* Timeout for current iteration */
230 GSource *source_list;
231 gint in_check_or_prepare;
233 GPollRec *poll_records, *poll_records_tail;
234 guint n_poll_records;
235 GPollFD *cached_poll_array;
236 guint cached_poll_array_size;
241 gboolean poll_waiting;
243 /* Flag indicating whether the set of fd's changed during a poll */
244 gboolean poll_changed;
249 gboolean time_is_fresh;
251 gboolean real_time_is_fresh;
254 struct _GSourceCallback
259 GDestroyNotify notify;
264 GMainContext *context;
269 struct _GTimeoutSource
277 struct _GChildWatchSource
284 #else /* G_OS_WIN32 */
286 gboolean child_exited;
287 #endif /* G_OS_WIN32 */
290 struct _GUnixSignalWatchSource
305 struct _GSourcePrivate
307 GSList *child_sources;
308 GSource *parent_source;
311 #define LOCK_CONTEXT(context) g_static_mutex_lock (&context->mutex)
312 #define UNLOCK_CONTEXT(context) g_static_mutex_unlock (&context->mutex)
313 #define G_THREAD_SELF g_thread_self ()
315 #define SOURCE_DESTROYED(source) (((source)->flags & G_HOOK_FLAG_ACTIVE) == 0)
316 #define SOURCE_BLOCKED(source) (((source)->flags & G_HOOK_FLAG_IN_CALL) != 0 && \
317 ((source)->flags & G_SOURCE_CAN_RECURSE) == 0)
319 #define SOURCE_UNREF(source, context) \
321 if ((source)->ref_count > 1) \
322 (source)->ref_count--; \
324 g_source_unref_internal ((source), (context), TRUE); \
328 /* Forward declarations */
330 static void g_source_unref_internal (GSource *source,
331 GMainContext *context,
333 static void g_source_destroy_internal (GSource *source,
334 GMainContext *context,
336 static void g_source_set_priority_unlocked (GSource *source,
337 GMainContext *context,
339 static void g_main_context_poll (GMainContext *context,
344 static void g_main_context_add_poll_unlocked (GMainContext *context,
347 static void g_main_context_remove_poll_unlocked (GMainContext *context,
349 static void g_main_context_wakeup_unlocked (GMainContext *context);
351 static void _g_main_wake_up_all_contexts (void);
353 static gboolean g_timeout_prepare (GSource *source,
355 static gboolean g_timeout_check (GSource *source);
356 static gboolean g_timeout_dispatch (GSource *source,
357 GSourceFunc callback,
359 static gboolean g_child_watch_prepare (GSource *source,
361 static gboolean g_child_watch_check (GSource *source);
362 static gboolean g_child_watch_dispatch (GSource *source,
363 GSourceFunc callback,
366 static gpointer unix_signal_helper_thread (gpointer data) G_GNUC_NORETURN;
367 static void g_unix_signal_handler (int signum);
368 static gboolean g_unix_signal_watch_prepare (GSource *source,
370 static gboolean g_unix_signal_watch_check (GSource *source);
371 static gboolean g_unix_signal_watch_dispatch (GSource *source,
372 GSourceFunc callback,
374 static void g_unix_signal_watch_finalize (GSource *source);
376 static gboolean g_idle_prepare (GSource *source,
378 static gboolean g_idle_check (GSource *source);
379 static gboolean g_idle_dispatch (GSource *source,
380 GSourceFunc callback,
383 static GMainContext *glib_worker_context;
385 G_LOCK_DEFINE_STATIC (main_loop);
386 static GMainContext *default_main_context;
390 /* The UNIX signal pipe contains a single byte specifying which
391 * signal was received.
393 #define _UNIX_SIGNAL_PIPE_SIGCHLD_CHAR 'C'
394 #define _UNIX_SIGNAL_PIPE_SIGHUP_CHAR 'H'
395 #define _UNIX_SIGNAL_PIPE_SIGINT_CHAR 'I'
396 #define _UNIX_SIGNAL_PIPE_SIGTERM_CHAR 'T'
397 /* Guards all the data below */
398 G_LOCK_DEFINE_STATIC (unix_signal_lock);
399 static gboolean unix_signal_initialized;
400 static sigset_t unix_signal_mask;
401 static gint unix_signal_wake_up_pipe[2];
402 GSList *unix_signal_watches;
404 /* Not guarded ( FIXME should it be? ) */
405 static gint child_watch_count = 1;
407 static GSourceFuncs g_unix_signal_funcs =
409 g_unix_signal_watch_prepare,
410 g_unix_signal_watch_check,
411 g_unix_signal_watch_dispatch,
412 g_unix_signal_watch_finalize
414 #endif /* !G_OS_WIN32 */
415 G_LOCK_DEFINE_STATIC (main_context_list);
416 static GSList *main_context_list = NULL;
418 GSourceFuncs g_timeout_funcs =
426 GSourceFuncs g_child_watch_funcs =
428 g_child_watch_prepare,
430 g_child_watch_dispatch,
434 GSourceFuncs g_idle_funcs =
443 * g_main_context_ref:
444 * @context: a #GMainContext
446 * Increases the reference count on a #GMainContext object by one.
448 * Returns: the @context that was passed in (since 2.6)
451 g_main_context_ref (GMainContext *context)
453 g_return_val_if_fail (context != NULL, NULL);
454 g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL);
456 g_atomic_int_inc (&context->ref_count);
462 poll_rec_list_free (GMainContext *context,
465 g_slice_free_chain (GPollRec, list, next);
469 * g_main_context_unref:
470 * @context: a #GMainContext
472 * Decreases the reference count on a #GMainContext object by one. If
473 * the result is zero, free the context and free all associated memory.
476 g_main_context_unref (GMainContext *context)
479 g_return_if_fail (context != NULL);
480 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
482 if (!g_atomic_int_dec_and_test (&context->ref_count))
485 G_LOCK (main_context_list);
486 main_context_list = g_slist_remove (main_context_list, context);
487 G_UNLOCK (main_context_list);
489 source = context->source_list;
492 GSource *next = source->next;
493 g_source_destroy_internal (source, context, FALSE);
497 g_static_mutex_free (&context->mutex);
499 g_ptr_array_free (context->pending_dispatches, TRUE);
500 g_free (context->cached_poll_array);
502 poll_rec_list_free (context, context->poll_records);
504 g_wakeup_free (context->wakeup);
506 if (context->cond != NULL)
507 g_cond_free (context->cond);
513 g_main_context_init_pipe (GMainContext *context)
515 context->wakeup = g_wakeup_new ();
516 g_wakeup_get_pollfd (context->wakeup, &context->wake_up_rec);
517 g_main_context_add_poll_unlocked (context, 0, &context->wake_up_rec);
521 * g_main_context_new:
523 * Creates a new #GMainContext structure.
525 * Return value: the new #GMainContext
528 g_main_context_new (void)
530 GMainContext *context;
532 g_thread_init_glib ();
534 context = g_new0 (GMainContext, 1);
536 #ifdef G_MAIN_POLL_DEBUG
538 static gboolean beenhere = FALSE;
542 if (getenv ("G_MAIN_POLL_DEBUG") != NULL)
543 _g_main_poll_debug = TRUE;
549 g_static_mutex_init (&context->mutex);
551 context->owner = NULL;
552 context->waiters = NULL;
554 context->ref_count = 1;
556 context->next_id = 1;
558 context->source_list = NULL;
560 context->poll_func = g_poll;
562 context->cached_poll_array = NULL;
563 context->cached_poll_array_size = 0;
565 context->pending_dispatches = g_ptr_array_new ();
567 context->time_is_fresh = FALSE;
568 context->real_time_is_fresh = FALSE;
570 g_main_context_init_pipe (context);
572 G_LOCK (main_context_list);
573 main_context_list = g_slist_append (main_context_list, context);
575 #ifdef G_MAIN_POLL_DEBUG
576 if (_g_main_poll_debug)
577 g_print ("created context=%p\n", context);
580 G_UNLOCK (main_context_list);
586 * g_main_context_default:
588 * Returns the global default main context. This is the main context
589 * used for main loop functions when a main loop is not explicitly
590 * specified, and corresponds to the "main" main loop. See also
591 * g_main_context_get_thread_default().
593 * Return value: (transfer none): the global default main context.
596 g_main_context_default (void)
602 if (!default_main_context)
604 default_main_context = g_main_context_new ();
605 #ifdef G_MAIN_POLL_DEBUG
606 if (_g_main_poll_debug)
607 g_print ("default context=%p\n", default_main_context);
611 G_UNLOCK (main_loop);
613 return default_main_context;
616 static GStaticPrivate thread_context_stack = G_STATIC_PRIVATE_INIT;
619 free_context_stack (gpointer data)
621 GQueue *stack = data;
622 GMainContext *context;
624 while (!g_queue_is_empty (stack))
626 context = g_queue_pop_head (stack);
627 g_main_context_release (context);
629 g_main_context_unref (context);
631 g_queue_free (stack);
635 * g_main_context_push_thread_default:
636 * @context: a #GMainContext, or %NULL for the global default context
638 * Acquires @context and sets it as the thread-default context for the
639 * current thread. This will cause certain asynchronous operations
640 * (such as most <link linkend="gio">gio</link>-based I/O) which are
641 * started in this thread to run under @context and deliver their
642 * results to its main loop, rather than running under the global
643 * default context in the main thread. Note that calling this function
644 * changes the context returned by
645 * g_main_context_get_thread_default(), <emphasis>not</emphasis> the
646 * one returned by g_main_context_default(), so it does not affect the
647 * context used by functions like g_idle_add().
649 * Normally you would call this function shortly after creating a new
650 * thread, passing it a #GMainContext which will be run by a
651 * #GMainLoop in that thread, to set a new default context for all
652 * async operations in that thread. (In this case, you don't need to
653 * ever call g_main_context_pop_thread_default().) In some cases
654 * however, you may want to schedule a single operation in a
655 * non-default context, or temporarily use a non-default context in
656 * the main thread. In that case, you can wrap the call to the
657 * asynchronous operation inside a
658 * g_main_context_push_thread_default() /
659 * g_main_context_pop_thread_default() pair, but it is up to you to
660 * ensure that no other asynchronous operations accidentally get
661 * started while the non-default context is active.
663 * Beware that libraries that predate this function may not correctly
664 * handle being used from a thread with a thread-default context. Eg,
665 * see g_file_supports_thread_contexts().
670 g_main_context_push_thread_default (GMainContext *context)
673 gboolean acquired_context;
675 acquired_context = g_main_context_acquire (context);
676 g_return_if_fail (acquired_context);
678 if (context == g_main_context_default ())
681 g_main_context_ref (context);
683 stack = g_static_private_get (&thread_context_stack);
686 stack = g_queue_new ();
687 g_static_private_set (&thread_context_stack, stack,
691 g_queue_push_head (stack, context);
695 * g_main_context_pop_thread_default:
696 * @context: a #GMainContext object, or %NULL
698 * Pops @context off the thread-default context stack (verifying that
699 * it was on the top of the stack).
704 g_main_context_pop_thread_default (GMainContext *context)
708 if (context == g_main_context_default ())
711 stack = g_static_private_get (&thread_context_stack);
713 g_return_if_fail (stack != NULL);
714 g_return_if_fail (g_queue_peek_head (stack) == context);
716 g_queue_pop_head (stack);
718 g_main_context_release (context);
720 g_main_context_unref (context);
724 * g_main_context_get_thread_default:
726 * Gets the thread-default #GMainContext for this thread. Asynchronous
727 * operations that want to be able to be run in contexts other than
728 * the default one should call this method to get a #GMainContext to
729 * add their #GSource<!-- -->s to. (Note that even in single-threaded
730 * programs applications may sometimes want to temporarily push a
731 * non-default context, so it is not safe to assume that this will
732 * always return %NULL if threads are not initialized.)
734 * Returns: (transfer none): the thread-default #GMainContext, or
735 * %NULL if the thread-default context is the global default context.
740 g_main_context_get_thread_default (void)
744 stack = g_static_private_get (&thread_context_stack);
746 return g_queue_peek_head (stack);
751 /* Hooks for adding to the main loop */
755 * @source_funcs: structure containing functions that implement
756 * the sources behavior.
757 * @struct_size: size of the #GSource structure to create.
759 * Creates a new #GSource structure. The size is specified to
760 * allow creating structures derived from #GSource that contain
761 * additional data. The size passed in must be at least
762 * <literal>sizeof (GSource)</literal>.
764 * The source will not initially be associated with any #GMainContext
765 * and must be added to one with g_source_attach() before it will be
768 * Return value: the newly-created #GSource.
771 g_source_new (GSourceFuncs *source_funcs,
776 g_return_val_if_fail (source_funcs != NULL, NULL);
777 g_return_val_if_fail (struct_size >= sizeof (GSource), NULL);
779 source = (GSource*) g_malloc0 (struct_size);
781 source->source_funcs = source_funcs;
782 source->ref_count = 1;
784 source->priority = G_PRIORITY_DEFAULT;
786 source->flags = G_HOOK_FLAG_ACTIVE;
788 /* NULL/0 initialization for all other fields */
793 /* Holds context's lock
796 g_source_list_add (GSource *source,
797 GMainContext *context)
799 GSource *tmp_source, *last_source;
801 if (source->priv && source->priv->parent_source)
803 /* Put the source immediately before its parent */
804 tmp_source = source->priv->parent_source;
805 last_source = source->priv->parent_source->prev;
810 tmp_source = context->source_list;
811 while (tmp_source && tmp_source->priority <= source->priority)
813 last_source = tmp_source;
814 tmp_source = tmp_source->next;
818 source->next = tmp_source;
820 tmp_source->prev = source;
822 source->prev = last_source;
824 last_source->next = source;
826 context->source_list = source;
829 /* Holds context's lock
832 g_source_list_remove (GSource *source,
833 GMainContext *context)
836 source->prev->next = source->next;
838 context->source_list = source->next;
841 source->next->prev = source->prev;
848 g_source_attach_unlocked (GSource *source,
849 GMainContext *context)
854 source->context = context;
855 result = source->source_id = context->next_id++;
858 g_source_list_add (source, context);
860 tmp_list = source->poll_fds;
863 g_main_context_add_poll_unlocked (context, source->priority, tmp_list->data);
864 tmp_list = tmp_list->next;
869 tmp_list = source->priv->child_sources;
872 g_source_attach_unlocked (tmp_list->data, context);
873 tmp_list = tmp_list->next;
882 * @source: a #GSource
883 * @context: a #GMainContext (if %NULL, the default context will be used)
885 * Adds a #GSource to a @context so that it will be executed within
886 * that context. Remove it by calling g_source_destroy().
888 * Return value: the ID (greater than 0) for the source within the
892 g_source_attach (GSource *source,
893 GMainContext *context)
897 g_return_val_if_fail (source->context == NULL, 0);
898 g_return_val_if_fail (!SOURCE_DESTROYED (source), 0);
901 context = g_main_context_default ();
903 LOCK_CONTEXT (context);
905 result = g_source_attach_unlocked (source, context);
907 /* Now wake up the main loop if it is waiting in the poll() */
908 g_main_context_wakeup_unlocked (context);
910 UNLOCK_CONTEXT (context);
916 g_source_destroy_internal (GSource *source,
917 GMainContext *context,
921 LOCK_CONTEXT (context);
923 if (!SOURCE_DESTROYED (source))
926 gpointer old_cb_data;
927 GSourceCallbackFuncs *old_cb_funcs;
929 source->flags &= ~G_HOOK_FLAG_ACTIVE;
931 old_cb_data = source->callback_data;
932 old_cb_funcs = source->callback_funcs;
934 source->callback_data = NULL;
935 source->callback_funcs = NULL;
939 UNLOCK_CONTEXT (context);
940 old_cb_funcs->unref (old_cb_data);
941 LOCK_CONTEXT (context);
944 if (!SOURCE_BLOCKED (source))
946 tmp_list = source->poll_fds;
949 g_main_context_remove_poll_unlocked (context, tmp_list->data);
950 tmp_list = tmp_list->next;
954 if (source->priv && source->priv->child_sources)
956 /* This is safe because even if a child_source finalizer or
957 * closure notify tried to modify source->priv->child_sources
958 * from outside the lock, it would fail since
959 * SOURCE_DESTROYED(source) is now TRUE.
961 tmp_list = source->priv->child_sources;
964 g_source_destroy_internal (tmp_list->data, context, TRUE);
965 g_source_unref_internal (tmp_list->data, context, TRUE);
966 tmp_list = tmp_list->next;
968 g_slist_free (source->priv->child_sources);
969 source->priv->child_sources = NULL;
972 g_source_unref_internal (source, context, TRUE);
976 UNLOCK_CONTEXT (context);
981 * @source: a #GSource
983 * Removes a source from its #GMainContext, if any, and mark it as
984 * destroyed. The source cannot be subsequently added to another
988 g_source_destroy (GSource *source)
990 GMainContext *context;
992 g_return_if_fail (source != NULL);
994 context = source->context;
997 g_source_destroy_internal (source, context, FALSE);
999 source->flags &= ~G_HOOK_FLAG_ACTIVE;
1004 * @source: a #GSource
1006 * Returns the numeric ID for a particular source. The ID of a source
1007 * is a positive integer which is unique within a particular main loop
1008 * context. The reverse
1009 * mapping from ID to source is done by g_main_context_find_source_by_id().
1011 * Return value: the ID (greater than 0) for the source
1014 g_source_get_id (GSource *source)
1018 g_return_val_if_fail (source != NULL, 0);
1019 g_return_val_if_fail (source->context != NULL, 0);
1021 LOCK_CONTEXT (source->context);
1022 result = source->source_id;
1023 UNLOCK_CONTEXT (source->context);
1029 * g_source_get_context:
1030 * @source: a #GSource
1032 * Gets the #GMainContext with which the source is associated.
1033 * Calling this function on a destroyed source is an error.
1035 * Return value: (transfer none): the #GMainContext with which the
1036 * source is associated, or %NULL if the context has not
1037 * yet been added to a source.
1040 g_source_get_context (GSource *source)
1042 g_return_val_if_fail (!SOURCE_DESTROYED (source), NULL);
1044 return source->context;
1048 * g_source_add_poll:
1049 * @source:a #GSource
1050 * @fd: a #GPollFD structure holding information about a file
1051 * descriptor to watch.
1053 * Adds a file descriptor to the set of file descriptors polled for
1054 * this source. This is usually combined with g_source_new() to add an
1055 * event source. The event source's check function will typically test
1056 * the @revents field in the #GPollFD struct and return %TRUE if events need
1060 g_source_add_poll (GSource *source,
1063 GMainContext *context;
1065 g_return_if_fail (source != NULL);
1066 g_return_if_fail (fd != NULL);
1067 g_return_if_fail (!SOURCE_DESTROYED (source));
1069 context = source->context;
1072 LOCK_CONTEXT (context);
1074 source->poll_fds = g_slist_prepend (source->poll_fds, fd);
1078 if (!SOURCE_BLOCKED (source))
1079 g_main_context_add_poll_unlocked (context, source->priority, fd);
1080 UNLOCK_CONTEXT (context);
1085 * g_source_remove_poll:
1086 * @source:a #GSource
1087 * @fd: a #GPollFD structure previously passed to g_source_add_poll().
1089 * Removes a file descriptor from the set of file descriptors polled for
1093 g_source_remove_poll (GSource *source,
1096 GMainContext *context;
1098 g_return_if_fail (source != NULL);
1099 g_return_if_fail (fd != NULL);
1100 g_return_if_fail (!SOURCE_DESTROYED (source));
1102 context = source->context;
1105 LOCK_CONTEXT (context);
1107 source->poll_fds = g_slist_remove (source->poll_fds, fd);
1111 if (!SOURCE_BLOCKED (source))
1112 g_main_context_remove_poll_unlocked (context, fd);
1113 UNLOCK_CONTEXT (context);
1118 * g_source_add_child_source:
1119 * @source:a #GSource
1120 * @child_source: a second #GSource that @source should "poll"
1122 * Adds @child_source to @source as a "polled" source; when @source is
1123 * added to a #GMainContext, @child_source will be automatically added
1124 * with the same priority, when @child_source is triggered, it will
1125 * cause @source to dispatch (in addition to calling its own
1126 * callback), and when @source is destroyed, it will destroy
1127 * @child_source as well. (@source will also still be dispatched if
1128 * its own prepare/check functions indicate that it is ready.)
1130 * If you don't need @child_source to do anything on its own when it
1131 * triggers, you can call g_source_set_dummy_callback() on it to set a
1132 * callback that does nothing (except return %TRUE if appropriate).
1134 * @source will hold a reference on @child_source while @child_source
1135 * is attached to it.
1140 g_source_add_child_source (GSource *source,
1141 GSource *child_source)
1143 GMainContext *context;
1145 g_return_if_fail (source != NULL);
1146 g_return_if_fail (child_source != NULL);
1147 g_return_if_fail (!SOURCE_DESTROYED (source));
1148 g_return_if_fail (!SOURCE_DESTROYED (child_source));
1149 g_return_if_fail (child_source->context == NULL);
1150 g_return_if_fail (child_source->priv == NULL || child_source->priv->parent_source == NULL);
1152 context = source->context;
1155 LOCK_CONTEXT (context);
1158 source->priv = g_slice_new0 (GSourcePrivate);
1159 if (!child_source->priv)
1160 child_source->priv = g_slice_new0 (GSourcePrivate);
1162 source->priv->child_sources = g_slist_prepend (source->priv->child_sources,
1163 g_source_ref (child_source));
1164 child_source->priv->parent_source = source;
1165 g_source_set_priority_unlocked (child_source, context, source->priority);
1169 UNLOCK_CONTEXT (context);
1170 g_source_attach (child_source, context);
1175 * g_source_remove_child_source:
1176 * @source:a #GSource
1177 * @child_source: a #GSource previously passed to
1178 * g_source_add_child_source().
1180 * Detaches @child_source from @source and destroys it.
1185 g_source_remove_child_source (GSource *source,
1186 GSource *child_source)
1188 GMainContext *context;
1190 g_return_if_fail (source != NULL);
1191 g_return_if_fail (child_source != NULL);
1192 g_return_if_fail (child_source->priv != NULL && child_source->priv->parent_source == source);
1193 g_return_if_fail (!SOURCE_DESTROYED (source));
1194 g_return_if_fail (!SOURCE_DESTROYED (child_source));
1196 context = source->context;
1199 LOCK_CONTEXT (context);
1201 source->priv->child_sources = g_slist_remove (source->priv->child_sources, child_source);
1202 g_source_destroy_internal (child_source, context, TRUE);
1203 g_source_unref_internal (child_source, context, TRUE);
1206 UNLOCK_CONTEXT (context);
1210 * g_source_set_callback_indirect:
1211 * @source: the source
1212 * @callback_data: pointer to callback data "object"
1213 * @callback_funcs: functions for reference counting @callback_data
1214 * and getting the callback and data
1216 * Sets the callback function storing the data as a refcounted callback
1217 * "object". This is used internally. Note that calling
1218 * g_source_set_callback_indirect() assumes
1219 * an initial reference count on @callback_data, and thus
1220 * @callback_funcs->unref will eventually be called once more
1221 * than @callback_funcs->ref.
1224 g_source_set_callback_indirect (GSource *source,
1225 gpointer callback_data,
1226 GSourceCallbackFuncs *callback_funcs)
1228 GMainContext *context;
1229 gpointer old_cb_data;
1230 GSourceCallbackFuncs *old_cb_funcs;
1232 g_return_if_fail (source != NULL);
1233 g_return_if_fail (callback_funcs != NULL || callback_data == NULL);
1235 context = source->context;
1238 LOCK_CONTEXT (context);
1240 old_cb_data = source->callback_data;
1241 old_cb_funcs = source->callback_funcs;
1243 source->callback_data = callback_data;
1244 source->callback_funcs = callback_funcs;
1247 UNLOCK_CONTEXT (context);
1250 old_cb_funcs->unref (old_cb_data);
1254 g_source_callback_ref (gpointer cb_data)
1256 GSourceCallback *callback = cb_data;
1258 callback->ref_count++;
1263 g_source_callback_unref (gpointer cb_data)
1265 GSourceCallback *callback = cb_data;
1267 callback->ref_count--;
1268 if (callback->ref_count == 0)
1270 if (callback->notify)
1271 callback->notify (callback->data);
1277 g_source_callback_get (gpointer cb_data,
1282 GSourceCallback *callback = cb_data;
1284 *func = callback->func;
1285 *data = callback->data;
1288 static GSourceCallbackFuncs g_source_callback_funcs = {
1289 g_source_callback_ref,
1290 g_source_callback_unref,
1291 g_source_callback_get,
1295 * g_source_set_callback:
1296 * @source: the source
1297 * @func: a callback function
1298 * @data: the data to pass to callback function
1299 * @notify: a function to call when @data is no longer in use, or %NULL.
1301 * Sets the callback function for a source. The callback for a source is
1302 * called from the source's dispatch function.
1304 * The exact type of @func depends on the type of source; ie. you
1305 * should not count on @func being called with @data as its first
1308 * Typically, you won't use this function. Instead use functions specific
1309 * to the type of source you are using.
1312 g_source_set_callback (GSource *source,
1315 GDestroyNotify notify)
1317 GSourceCallback *new_callback;
1319 g_return_if_fail (source != NULL);
1321 new_callback = g_new (GSourceCallback, 1);
1323 new_callback->ref_count = 1;
1324 new_callback->func = func;
1325 new_callback->data = data;
1326 new_callback->notify = notify;
1328 g_source_set_callback_indirect (source, new_callback, &g_source_callback_funcs);
1333 * g_source_set_funcs:
1334 * @source: a #GSource
1335 * @funcs: the new #GSourceFuncs
1337 * Sets the source functions (can be used to override
1338 * default implementations) of an unattached source.
1343 g_source_set_funcs (GSource *source,
1344 GSourceFuncs *funcs)
1346 g_return_if_fail (source != NULL);
1347 g_return_if_fail (source->context == NULL);
1348 g_return_if_fail (source->ref_count > 0);
1349 g_return_if_fail (funcs != NULL);
1351 source->source_funcs = funcs;
1355 g_source_set_priority_unlocked (GSource *source,
1356 GMainContext *context,
1361 source->priority = priority;
1365 /* Remove the source from the context's source and then
1366 * add it back so it is sorted in the correct place
1368 g_source_list_remove (source, source->context);
1369 g_source_list_add (source, source->context);
1371 if (!SOURCE_BLOCKED (source))
1373 tmp_list = source->poll_fds;
1376 g_main_context_remove_poll_unlocked (context, tmp_list->data);
1377 g_main_context_add_poll_unlocked (context, priority, tmp_list->data);
1379 tmp_list = tmp_list->next;
1384 if (source->priv && source->priv->child_sources)
1386 tmp_list = source->priv->child_sources;
1389 g_source_set_priority_unlocked (tmp_list->data, context, priority);
1390 tmp_list = tmp_list->next;
1396 * g_source_set_priority:
1397 * @source: a #GSource
1398 * @priority: the new priority.
1400 * Sets the priority of a source. While the main loop is being run, a
1401 * source will be dispatched if it is ready to be dispatched and no
1402 * sources at a higher (numerically smaller) priority are ready to be
1406 g_source_set_priority (GSource *source,
1409 GMainContext *context;
1411 g_return_if_fail (source != NULL);
1413 context = source->context;
1416 LOCK_CONTEXT (context);
1417 g_source_set_priority_unlocked (source, context, priority);
1419 UNLOCK_CONTEXT (source->context);
1423 * g_source_get_priority:
1424 * @source: a #GSource
1426 * Gets the priority of a source.
1428 * Return value: the priority of the source
1431 g_source_get_priority (GSource *source)
1433 g_return_val_if_fail (source != NULL, 0);
1435 return source->priority;
1439 * g_source_set_can_recurse:
1440 * @source: a #GSource
1441 * @can_recurse: whether recursion is allowed for this source
1443 * Sets whether a source can be called recursively. If @can_recurse is
1444 * %TRUE, then while the source is being dispatched then this source
1445 * will be processed normally. Otherwise, all processing of this
1446 * source is blocked until the dispatch function returns.
1449 g_source_set_can_recurse (GSource *source,
1450 gboolean can_recurse)
1452 GMainContext *context;
1454 g_return_if_fail (source != NULL);
1456 context = source->context;
1459 LOCK_CONTEXT (context);
1462 source->flags |= G_SOURCE_CAN_RECURSE;
1464 source->flags &= ~G_SOURCE_CAN_RECURSE;
1467 UNLOCK_CONTEXT (context);
1471 * g_source_get_can_recurse:
1472 * @source: a #GSource
1474 * Checks whether a source is allowed to be called recursively.
1475 * see g_source_set_can_recurse().
1477 * Return value: whether recursion is allowed.
1480 g_source_get_can_recurse (GSource *source)
1482 g_return_val_if_fail (source != NULL, FALSE);
1484 return (source->flags & G_SOURCE_CAN_RECURSE) != 0;
1489 * g_source_set_name:
1490 * @source: a #GSource
1491 * @name: debug name for the source
1493 * Sets a name for the source, used in debugging and profiling.
1494 * The name defaults to #NULL.
1496 * The source name should describe in a human-readable way
1497 * what the source does. For example, "X11 event queue"
1498 * or "GTK+ repaint idle handler" or whatever it is.
1500 * It is permitted to call this function multiple times, but is not
1501 * recommended due to the potential performance impact. For example,
1502 * one could change the name in the "check" function of a #GSourceFuncs
1503 * to include details like the event type in the source name.
1508 g_source_set_name (GSource *source,
1511 g_return_if_fail (source != NULL);
1513 /* setting back to NULL is allowed, just because it's
1514 * weird if get_name can return NULL but you can't
1518 g_free (source->name);
1519 source->name = g_strdup (name);
1523 * g_source_get_name:
1524 * @source: a #GSource
1526 * Gets a name for the source, used in debugging and profiling.
1527 * The name may be #NULL if it has never been set with
1528 * g_source_set_name().
1530 * Return value: the name of the source
1534 g_source_get_name (GSource *source)
1536 g_return_val_if_fail (source != NULL, NULL);
1538 return source->name;
1542 * g_source_set_name_by_id:
1543 * @tag: a #GSource ID
1544 * @name: debug name for the source
1546 * Sets the name of a source using its ID.
1548 * This is a convenience utility to set source names from the return
1549 * value of g_idle_add(), g_timeout_add(), etc.
1554 g_source_set_name_by_id (guint tag,
1559 g_return_if_fail (tag > 0);
1561 source = g_main_context_find_source_by_id (NULL, tag);
1565 g_source_set_name (source, name);
1571 * @source: a #GSource
1573 * Increases the reference count on a source by one.
1575 * Return value: @source
1578 g_source_ref (GSource *source)
1580 GMainContext *context;
1582 g_return_val_if_fail (source != NULL, NULL);
1584 context = source->context;
1587 LOCK_CONTEXT (context);
1589 source->ref_count++;
1592 UNLOCK_CONTEXT (context);
1597 /* g_source_unref() but possible to call within context lock
1600 g_source_unref_internal (GSource *source,
1601 GMainContext *context,
1604 gpointer old_cb_data = NULL;
1605 GSourceCallbackFuncs *old_cb_funcs = NULL;
1607 g_return_if_fail (source != NULL);
1609 if (!have_lock && context)
1610 LOCK_CONTEXT (context);
1612 source->ref_count--;
1613 if (source->ref_count == 0)
1615 old_cb_data = source->callback_data;
1616 old_cb_funcs = source->callback_funcs;
1618 source->callback_data = NULL;
1619 source->callback_funcs = NULL;
1623 if (!SOURCE_DESTROYED (source))
1624 g_warning (G_STRLOC ": ref_count == 0, but source was still attached to a context!");
1625 g_source_list_remove (source, context);
1628 if (source->source_funcs->finalize)
1631 UNLOCK_CONTEXT (context);
1632 source->source_funcs->finalize (source);
1634 LOCK_CONTEXT (context);
1637 g_free (source->name);
1638 source->name = NULL;
1640 g_slist_free (source->poll_fds);
1641 source->poll_fds = NULL;
1645 g_slice_free (GSourcePrivate, source->priv);
1646 source->priv = NULL;
1652 if (!have_lock && context)
1653 UNLOCK_CONTEXT (context);
1658 UNLOCK_CONTEXT (context);
1660 old_cb_funcs->unref (old_cb_data);
1663 LOCK_CONTEXT (context);
1669 * @source: a #GSource
1671 * Decreases the reference count of a source by one. If the
1672 * resulting reference count is zero the source and associated
1673 * memory will be destroyed.
1676 g_source_unref (GSource *source)
1678 g_return_if_fail (source != NULL);
1680 g_source_unref_internal (source, source->context, FALSE);
1684 * g_main_context_find_source_by_id:
1685 * @context: a #GMainContext (if %NULL, the default context will be used)
1686 * @source_id: the source ID, as returned by g_source_get_id().
1688 * Finds a #GSource given a pair of context and ID.
1690 * Return value: (transfer none): the #GSource if found, otherwise, %NULL
1693 g_main_context_find_source_by_id (GMainContext *context,
1698 g_return_val_if_fail (source_id > 0, NULL);
1700 if (context == NULL)
1701 context = g_main_context_default ();
1703 LOCK_CONTEXT (context);
1705 source = context->source_list;
1708 if (!SOURCE_DESTROYED (source) &&
1709 source->source_id == source_id)
1711 source = source->next;
1714 UNLOCK_CONTEXT (context);
1720 * g_main_context_find_source_by_funcs_user_data:
1721 * @context: a #GMainContext (if %NULL, the default context will be used).
1722 * @funcs: the @source_funcs passed to g_source_new().
1723 * @user_data: the user data from the callback.
1725 * Finds a source with the given source functions and user data. If
1726 * multiple sources exist with the same source function and user data,
1727 * the first one found will be returned.
1729 * Return value: (transfer none): the source, if one was found, otherwise %NULL
1732 g_main_context_find_source_by_funcs_user_data (GMainContext *context,
1733 GSourceFuncs *funcs,
1738 g_return_val_if_fail (funcs != NULL, NULL);
1740 if (context == NULL)
1741 context = g_main_context_default ();
1743 LOCK_CONTEXT (context);
1745 source = context->source_list;
1748 if (!SOURCE_DESTROYED (source) &&
1749 source->source_funcs == funcs &&
1750 source->callback_funcs)
1752 GSourceFunc callback;
1753 gpointer callback_data;
1755 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
1757 if (callback_data == user_data)
1760 source = source->next;
1763 UNLOCK_CONTEXT (context);
1769 * g_main_context_find_source_by_user_data:
1770 * @context: a #GMainContext
1771 * @user_data: the user_data for the callback.
1773 * Finds a source with the given user data for the callback. If
1774 * multiple sources exist with the same user data, the first
1775 * one found will be returned.
1777 * Return value: (transfer none): the source, if one was found, otherwise %NULL
1780 g_main_context_find_source_by_user_data (GMainContext *context,
1785 if (context == NULL)
1786 context = g_main_context_default ();
1788 LOCK_CONTEXT (context);
1790 source = context->source_list;
1793 if (!SOURCE_DESTROYED (source) &&
1794 source->callback_funcs)
1796 GSourceFunc callback;
1797 gpointer callback_data = NULL;
1799 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
1801 if (callback_data == user_data)
1804 source = source->next;
1807 UNLOCK_CONTEXT (context);
1814 * @tag: the ID of the source to remove.
1816 * Removes the source with the given id from the default main context.
1818 * a #GSource is given by g_source_get_id(), or will be returned by the
1819 * functions g_source_attach(), g_idle_add(), g_idle_add_full(),
1820 * g_timeout_add(), g_timeout_add_full(), g_child_watch_add(),
1821 * g_child_watch_add_full(), g_io_add_watch(), and g_io_add_watch_full().
1823 * See also g_source_destroy(). You must use g_source_destroy() for sources
1824 * added to a non-default main context.
1826 * Return value: %TRUE if the source was found and removed.
1829 g_source_remove (guint tag)
1833 g_return_val_if_fail (tag > 0, FALSE);
1835 source = g_main_context_find_source_by_id (NULL, tag);
1837 g_source_destroy (source);
1839 return source != NULL;
1843 * g_source_remove_by_user_data:
1844 * @user_data: the user_data for the callback.
1846 * Removes a source from the default main loop context given the user
1847 * data for the callback. If multiple sources exist with the same user
1848 * data, only one will be destroyed.
1850 * Return value: %TRUE if a source was found and removed.
1853 g_source_remove_by_user_data (gpointer user_data)
1857 source = g_main_context_find_source_by_user_data (NULL, user_data);
1860 g_source_destroy (source);
1868 * g_source_remove_by_funcs_user_data:
1869 * @funcs: The @source_funcs passed to g_source_new()
1870 * @user_data: the user data for the callback
1872 * Removes a source from the default main loop context given the
1873 * source functions and user data. If multiple sources exist with the
1874 * same source functions and user data, only one will be destroyed.
1876 * Return value: %TRUE if a source was found and removed.
1879 g_source_remove_by_funcs_user_data (GSourceFuncs *funcs,
1884 g_return_val_if_fail (funcs != NULL, FALSE);
1886 source = g_main_context_find_source_by_funcs_user_data (NULL, funcs, user_data);
1889 g_source_destroy (source);
1897 * g_get_current_time:
1898 * @result: #GTimeVal structure in which to store current time.
1900 * Equivalent to the UNIX gettimeofday() function, but portable.
1902 * You may find g_get_real_time() to be more convenient.
1905 g_get_current_time (GTimeVal *result)
1910 g_return_if_fail (result != NULL);
1912 /*this is required on alpha, there the timeval structs are int's
1913 not longs and a cast only would fail horribly*/
1914 gettimeofday (&r, NULL);
1915 result->tv_sec = r.tv_sec;
1916 result->tv_usec = r.tv_usec;
1921 g_return_if_fail (result != NULL);
1923 GetSystemTimeAsFileTime (&ft);
1924 memmove (&time64, &ft, sizeof (FILETIME));
1926 /* Convert from 100s of nanoseconds since 1601-01-01
1927 * to Unix epoch. Yes, this is Y2038 unsafe.
1929 time64 -= G_GINT64_CONSTANT (116444736000000000);
1932 result->tv_sec = time64 / 1000000;
1933 result->tv_usec = time64 % 1000000;
1940 * Queries the system wall-clock time.
1942 * This call is functionally equivalent to g_get_current_time() except
1943 * that the return value is often more convenient than dealing with a
1946 * You should only use this call if you are actually interested in the real
1947 * wall-clock time. g_get_monotonic_time() is probably more useful for
1948 * measuring intervals.
1950 * Returns: the number of microseconds since January 1, 1970 UTC.
1955 g_get_real_time (void)
1959 g_get_current_time (&tv);
1961 return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec;
1965 * g_get_monotonic_time:
1967 * Queries the system monotonic time, if available.
1969 * On POSIX systems with clock_gettime() and %CLOCK_MONOTONIC this call
1970 * is a very shallow wrapper for that. Otherwise, we make a best effort
1971 * that probably involves returning the wall clock time (with at least
1972 * microsecond accuracy, subject to the limitations of the OS kernel).
1974 * It's important to note that POSIX %CLOCK_MONOTONIC does not count
1975 * time spent while the machine is suspended.
1977 * On Windows, "limitations of the OS kernel" is a rather substantial
1978 * statement. Depending on the configuration of the system, the wall
1979 * clock time is updated as infrequently as 64 times a second (which
1980 * is approximately every 16ms).
1982 * Returns: the monotonic time, in microseconds
1987 g_get_monotonic_time (void)
1989 #ifdef HAVE_CLOCK_GETTIME
1990 /* librt clock_gettime() is our first choice */
1992 #ifdef HAVE_MONOTONIC_CLOCK
1993 static volatile gsize clockid = 0;
1995 static clockid_t clockid = CLOCK_REALTIME;
1999 #ifdef HAVE_MONOTONIC_CLOCK
2000 if (g_once_init_enter (&clockid))
2002 clockid_t best_clockid;
2004 if (sysconf (_SC_MONOTONIC_CLOCK) >= 0)
2005 best_clockid = CLOCK_MONOTONIC;
2007 best_clockid = CLOCK_REALTIME;
2008 g_once_init_leave (&clockid, (gsize)best_clockid);
2012 clock_gettime (clockid, &ts);
2014 /* In theory monotonic time can have any epoch.
2016 * glib presently assumes the following:
2018 * 1) The epoch comes some time after the birth of Jesus of Nazareth, but
2019 * not more than 10000 years later.
2021 * 2) The current time also falls sometime within this range.
2023 * These two reasonable assumptions leave us with a maximum deviation from
2024 * the epoch of 10000 years, or 315569520000000000 seconds.
2026 * If we restrict ourselves to this range then the number of microseconds
2027 * will always fit well inside the constraints of a int64 (by a factor of
2030 * If you actually hit the following assertion, probably you should file a
2031 * bug against your operating system for being excessively silly.
2033 g_assert (G_GINT64_CONSTANT (-315569520000000000) < ts.tv_sec &&
2034 ts.tv_sec < G_GINT64_CONSTANT (315569520000000000));
2036 return (((gint64) ts.tv_sec) * 1000000) + (ts.tv_nsec / 1000);
2039 /* It may look like we are discarding accuracy on Windows (since its
2040 * current time is expressed in 100s of nanoseconds) but according to
2041 * many sources, the time is only updated 64 times per second, so
2042 * microsecond accuracy is more than enough.
2047 g_get_current_time (&tv);
2049 return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec;
2055 g_main_dispatch_free (gpointer dispatch)
2057 g_slice_free (GMainDispatch, dispatch);
2060 /* Running the main loop */
2062 static GMainDispatch *
2065 static GStaticPrivate depth_private = G_STATIC_PRIVATE_INIT;
2066 GMainDispatch *dispatch = g_static_private_get (&depth_private);
2069 dispatch = g_slice_new0 (GMainDispatch);
2070 g_static_private_set (&depth_private, dispatch, g_main_dispatch_free);
2079 * Returns the depth of the stack of calls to
2080 * g_main_context_dispatch() on any #GMainContext in the current thread.
2081 * That is, when called from the toplevel, it gives 0. When
2082 * called from within a callback from g_main_context_iteration()
2083 * (or g_main_loop_run(), etc.) it returns 1. When called from within
2084 * a callback to a recursive call to g_main_context_iteration(),
2085 * it returns 2. And so forth.
2087 * This function is useful in a situation like the following:
2088 * Imagine an extremely simple "garbage collected" system.
2091 * static GList *free_list;
2094 * allocate_memory (gsize size)
2096 * gpointer result = g_malloc (size);
2097 * free_list = g_list_prepend (free_list, result);
2102 * free_allocated_memory (void)
2105 * for (l = free_list; l; l = l->next);
2107 * g_list_free (free_list);
2115 * g_main_context_iteration (NULL, TRUE);
2116 * free_allocated_memory();
2120 * This works from an application, however, if you want to do the same
2121 * thing from a library, it gets more difficult, since you no longer
2122 * control the main loop. You might think you can simply use an idle
2123 * function to make the call to free_allocated_memory(), but that
2124 * doesn't work, since the idle function could be called from a
2125 * recursive callback. This can be fixed by using g_main_depth()
2129 * allocate_memory (gsize size)
2131 * FreeListBlock *block = g_new (FreeListBlock, 1);
2132 * block->mem = g_malloc (size);
2133 * block->depth = g_main_depth ();
2134 * free_list = g_list_prepend (free_list, block);
2135 * return block->mem;
2139 * free_allocated_memory (void)
2143 * int depth = g_main_depth ();
2144 * for (l = free_list; l; );
2146 * GList *next = l->next;
2147 * FreeListBlock *block = l->data;
2148 * if (block->depth > depth)
2150 * g_free (block->mem);
2152 * free_list = g_list_delete_link (free_list, l);
2160 * There is a temptation to use g_main_depth() to solve
2161 * problems with reentrancy. For instance, while waiting for data
2162 * to be received from the network in response to a menu item,
2163 * the menu item might be selected again. It might seem that
2164 * one could make the menu item's callback return immediately
2165 * and do nothing if g_main_depth() returns a value greater than 1.
2166 * However, this should be avoided since the user then sees selecting
2167 * the menu item do nothing. Furthermore, you'll find yourself adding
2168 * these checks all over your code, since there are doubtless many,
2169 * many things that the user could do. Instead, you can use the
2170 * following techniques:
2175 * Use gtk_widget_set_sensitive() or modal dialogs to prevent
2176 * the user from interacting with elements while the main
2177 * loop is recursing.
2182 * Avoid main loop recursion in situations where you can't handle
2183 * arbitrary callbacks. Instead, structure your code so that you
2184 * simply return to the main loop and then get called again when
2185 * there is more work to do.
2190 * Return value: The main loop recursion level in the current thread
2195 GMainDispatch *dispatch = get_dispatch ();
2196 return dispatch->depth;
2200 * g_main_current_source:
2202 * Returns the currently firing source for this thread.
2204 * Return value: (transfer none): The currently firing source or %NULL.
2209 g_main_current_source (void)
2211 GMainDispatch *dispatch = get_dispatch ();
2212 return dispatch->dispatching_sources ? dispatch->dispatching_sources->data : NULL;
2216 * g_source_is_destroyed:
2217 * @source: a #GSource
2219 * Returns whether @source has been destroyed.
2221 * This is important when you operate upon your objects
2222 * from within idle handlers, but may have freed the object
2223 * before the dispatch of your idle handler.
2227 * idle_callback (gpointer data)
2229 * SomeWidget *self = data;
2231 * GDK_THREADS_ENTER (<!-- -->);
2232 * /<!-- -->* do stuff with self *<!-- -->/
2233 * self->idle_id = 0;
2234 * GDK_THREADS_LEAVE (<!-- -->);
2240 * some_widget_do_stuff_later (SomeWidget *self)
2242 * self->idle_id = g_idle_add (idle_callback, self);
2246 * some_widget_finalize (GObject *object)
2248 * SomeWidget *self = SOME_WIDGET (object);
2250 * if (self->idle_id)
2251 * g_source_remove (self->idle_id);
2253 * G_OBJECT_CLASS (parent_class)->finalize (object);
2257 * This will fail in a multi-threaded application if the
2258 * widget is destroyed before the idle handler fires due
2259 * to the use after free in the callback. A solution, to
2260 * this particular problem, is to check to if the source
2261 * has already been destroy within the callback.
2265 * idle_callback (gpointer data)
2267 * SomeWidget *self = data;
2269 * GDK_THREADS_ENTER ();
2270 * if (!g_source_is_destroyed (g_main_current_source ()))
2272 * /<!-- -->* do stuff with self *<!-- -->/
2274 * GDK_THREADS_LEAVE ();
2280 * Return value: %TRUE if the source has been destroyed
2285 g_source_is_destroyed (GSource *source)
2287 return SOURCE_DESTROYED (source);
2290 /* Temporarily remove all this source's file descriptors from the
2291 * poll(), so that if data comes available for one of the file descriptors
2292 * we don't continually spin in the poll()
2294 /* HOLDS: source->context's lock */
2296 block_source (GSource *source)
2300 g_return_if_fail (!SOURCE_BLOCKED (source));
2302 tmp_list = source->poll_fds;
2305 g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
2306 tmp_list = tmp_list->next;
2310 /* HOLDS: source->context's lock */
2312 unblock_source (GSource *source)
2316 g_return_if_fail (!SOURCE_BLOCKED (source)); /* Source already unblocked */
2317 g_return_if_fail (!SOURCE_DESTROYED (source));
2319 tmp_list = source->poll_fds;
2322 g_main_context_add_poll_unlocked (source->context, source->priority, tmp_list->data);
2323 tmp_list = tmp_list->next;
2327 /* HOLDS: context's lock */
2329 g_main_dispatch (GMainContext *context)
2331 GMainDispatch *current = get_dispatch ();
2334 for (i = 0; i < context->pending_dispatches->len; i++)
2336 GSource *source = context->pending_dispatches->pdata[i];
2338 context->pending_dispatches->pdata[i] = NULL;
2341 source->flags &= ~G_SOURCE_READY;
2343 if (!SOURCE_DESTROYED (source))
2345 gboolean was_in_call;
2346 gpointer user_data = NULL;
2347 GSourceFunc callback = NULL;
2348 GSourceCallbackFuncs *cb_funcs;
2350 gboolean need_destroy;
2352 gboolean (*dispatch) (GSource *,
2355 GSList current_source_link;
2357 dispatch = source->source_funcs->dispatch;
2358 cb_funcs = source->callback_funcs;
2359 cb_data = source->callback_data;
2362 cb_funcs->ref (cb_data);
2364 if ((source->flags & G_SOURCE_CAN_RECURSE) == 0)
2365 block_source (source);
2367 was_in_call = source->flags & G_HOOK_FLAG_IN_CALL;
2368 source->flags |= G_HOOK_FLAG_IN_CALL;
2371 cb_funcs->get (cb_data, source, &callback, &user_data);
2373 UNLOCK_CONTEXT (context);
2376 /* The on-stack allocation of the GSList is unconventional, but
2377 * we know that the lifetime of the link is bounded to this
2378 * function as the link is kept in a thread specific list and
2379 * not manipulated outside of this function and its descendants.
2380 * Avoiding the overhead of a g_slist_alloc() is useful as many
2381 * applications do little more than dispatch events.
2383 * This is a performance hack - do not revert to g_slist_prepend()!
2385 current_source_link.data = source;
2386 current_source_link.next = current->dispatching_sources;
2387 current->dispatching_sources = ¤t_source_link;
2388 need_destroy = ! dispatch (source,
2391 g_assert (current->dispatching_sources == ¤t_source_link);
2392 current->dispatching_sources = current_source_link.next;
2396 cb_funcs->unref (cb_data);
2398 LOCK_CONTEXT (context);
2401 source->flags &= ~G_HOOK_FLAG_IN_CALL;
2403 if ((source->flags & G_SOURCE_CAN_RECURSE) == 0 &&
2404 !SOURCE_DESTROYED (source))
2405 unblock_source (source);
2407 /* Note: this depends on the fact that we can't switch
2408 * sources from one main context to another
2410 if (need_destroy && !SOURCE_DESTROYED (source))
2412 g_assert (source->context == context);
2413 g_source_destroy_internal (source, context, TRUE);
2417 SOURCE_UNREF (source, context);
2420 g_ptr_array_set_size (context->pending_dispatches, 0);
2423 /* Holds context's lock */
2424 static inline GSource *
2425 next_valid_source (GMainContext *context,
2428 GSource *new_source = source ? source->next : context->source_list;
2432 if (!SOURCE_DESTROYED (new_source))
2434 new_source->ref_count++;
2438 new_source = new_source->next;
2442 SOURCE_UNREF (source, context);
2448 * g_main_context_acquire:
2449 * @context: a #GMainContext
2451 * Tries to become the owner of the specified context.
2452 * If some other thread is the owner of the context,
2453 * returns %FALSE immediately. Ownership is properly
2454 * recursive: the owner can require ownership again
2455 * and will release ownership when g_main_context_release()
2456 * is called as many times as g_main_context_acquire().
2458 * You must be the owner of a context before you
2459 * can call g_main_context_prepare(), g_main_context_query(),
2460 * g_main_context_check(), g_main_context_dispatch().
2462 * Return value: %TRUE if the operation succeeded, and
2463 * this thread is now the owner of @context.
2466 g_main_context_acquire (GMainContext *context)
2468 gboolean result = FALSE;
2469 GThread *self = G_THREAD_SELF;
2471 if (context == NULL)
2472 context = g_main_context_default ();
2474 LOCK_CONTEXT (context);
2476 if (!context->owner)
2478 context->owner = self;
2479 g_assert (context->owner_count == 0);
2482 if (context->owner == self)
2484 context->owner_count++;
2488 UNLOCK_CONTEXT (context);
2494 * g_main_context_release:
2495 * @context: a #GMainContext
2497 * Releases ownership of a context previously acquired by this thread
2498 * with g_main_context_acquire(). If the context was acquired multiple
2499 * times, the ownership will be released only when g_main_context_release()
2500 * is called as many times as it was acquired.
2503 g_main_context_release (GMainContext *context)
2505 if (context == NULL)
2506 context = g_main_context_default ();
2508 LOCK_CONTEXT (context);
2510 context->owner_count--;
2511 if (context->owner_count == 0)
2513 context->owner = NULL;
2515 if (context->waiters)
2517 GMainWaiter *waiter = context->waiters->data;
2518 gboolean loop_internal_waiter =
2519 (waiter->mutex == g_static_mutex_get_mutex (&context->mutex));
2520 context->waiters = g_slist_delete_link (context->waiters,
2522 if (!loop_internal_waiter)
2523 g_mutex_lock (waiter->mutex);
2525 g_cond_signal (waiter->cond);
2527 if (!loop_internal_waiter)
2528 g_mutex_unlock (waiter->mutex);
2532 UNLOCK_CONTEXT (context);
2536 * g_main_context_wait:
2537 * @context: a #GMainContext
2538 * @cond: a condition variable
2539 * @mutex: a mutex, currently held
2541 * Tries to become the owner of the specified context,
2542 * as with g_main_context_acquire(). But if another thread
2543 * is the owner, atomically drop @mutex and wait on @cond until
2544 * that owner releases ownership or until @cond is signaled, then
2545 * try again (once) to become the owner.
2547 * Return value: %TRUE if the operation succeeded, and
2548 * this thread is now the owner of @context.
2551 g_main_context_wait (GMainContext *context,
2555 gboolean result = FALSE;
2556 GThread *self = G_THREAD_SELF;
2557 gboolean loop_internal_waiter;
2559 if (context == NULL)
2560 context = g_main_context_default ();
2562 loop_internal_waiter = (mutex == g_static_mutex_get_mutex (&context->mutex));
2564 if (!loop_internal_waiter)
2565 LOCK_CONTEXT (context);
2567 if (context->owner && context->owner != self)
2572 waiter.mutex = mutex;
2574 context->waiters = g_slist_append (context->waiters, &waiter);
2576 if (!loop_internal_waiter)
2577 UNLOCK_CONTEXT (context);
2578 g_cond_wait (cond, mutex);
2579 if (!loop_internal_waiter)
2580 LOCK_CONTEXT (context);
2582 context->waiters = g_slist_remove (context->waiters, &waiter);
2585 if (!context->owner)
2587 context->owner = self;
2588 g_assert (context->owner_count == 0);
2591 if (context->owner == self)
2593 context->owner_count++;
2597 if (!loop_internal_waiter)
2598 UNLOCK_CONTEXT (context);
2604 * g_main_context_prepare:
2605 * @context: a #GMainContext
2606 * @priority: location to store priority of highest priority
2607 * source already ready.
2609 * Prepares to poll sources within a main loop. The resulting information
2610 * for polling is determined by calling g_main_context_query ().
2612 * Return value: %TRUE if some source is ready to be dispatched
2616 g_main_context_prepare (GMainContext *context,
2621 gint current_priority = G_MAXINT;
2624 if (context == NULL)
2625 context = g_main_context_default ();
2627 LOCK_CONTEXT (context);
2629 context->time_is_fresh = FALSE;
2630 context->real_time_is_fresh = FALSE;
2632 if (context->in_check_or_prepare)
2634 g_warning ("g_main_context_prepare() called recursively from within a source's check() or "
2635 "prepare() member.");
2636 UNLOCK_CONTEXT (context);
2640 if (context->poll_waiting)
2642 g_warning("g_main_context_prepare(): main loop already active in another thread");
2643 UNLOCK_CONTEXT (context);
2647 context->poll_waiting = TRUE;
2650 /* If recursing, finish up current dispatch, before starting over */
2651 if (context->pending_dispatches)
2654 g_main_dispatch (context, ¤t_time);
2656 UNLOCK_CONTEXT (context);
2661 /* If recursing, clear list of pending dispatches */
2663 for (i = 0; i < context->pending_dispatches->len; i++)
2665 if (context->pending_dispatches->pdata[i])
2666 SOURCE_UNREF ((GSource *)context->pending_dispatches->pdata[i], context);
2668 g_ptr_array_set_size (context->pending_dispatches, 0);
2670 /* Prepare all sources */
2672 context->timeout = -1;
2674 source = next_valid_source (context, NULL);
2677 gint source_timeout = -1;
2679 if ((n_ready > 0) && (source->priority > current_priority))
2681 SOURCE_UNREF (source, context);
2684 if (SOURCE_BLOCKED (source))
2687 if (!(source->flags & G_SOURCE_READY))
2690 gboolean (*prepare) (GSource *source,
2693 prepare = source->source_funcs->prepare;
2694 context->in_check_or_prepare++;
2695 UNLOCK_CONTEXT (context);
2697 result = (*prepare) (source, &source_timeout);
2699 LOCK_CONTEXT (context);
2700 context->in_check_or_prepare--;
2704 GSource *ready_source = source;
2706 while (ready_source)
2708 ready_source->flags |= G_SOURCE_READY;
2709 ready_source = ready_source->priv ? ready_source->priv->parent_source : NULL;
2714 if (source->flags & G_SOURCE_READY)
2717 current_priority = source->priority;
2718 context->timeout = 0;
2721 if (source_timeout >= 0)
2723 if (context->timeout < 0)
2724 context->timeout = source_timeout;
2726 context->timeout = MIN (context->timeout, source_timeout);
2730 source = next_valid_source (context, source);
2733 UNLOCK_CONTEXT (context);
2736 *priority = current_priority;
2738 return (n_ready > 0);
2742 * g_main_context_query:
2743 * @context: a #GMainContext
2744 * @max_priority: maximum priority source to check
2745 * @timeout_: (out): location to store timeout to be used in polling
2746 * @fds: (out caller-allocates) (array length=n_fds): location to
2747 * store #GPollFD records that need to be polled.
2748 * @n_fds: length of @fds.
2750 * Determines information necessary to poll this main loop.
2752 * Return value: the number of records actually stored in @fds,
2753 * or, if more than @n_fds records need to be stored, the number
2754 * of records that need to be stored.
2757 g_main_context_query (GMainContext *context,
2766 LOCK_CONTEXT (context);
2768 pollrec = context->poll_records;
2770 while (pollrec && max_priority >= pollrec->priority)
2772 /* We need to include entries with fd->events == 0 in the array because
2773 * otherwise if the application changes fd->events behind our back and
2774 * makes it non-zero, we'll be out of sync when we check the fds[] array.
2775 * (Changing fd->events after adding an FD wasn't an anticipated use of
2776 * this API, but it occurs in practice.) */
2779 fds[n_poll].fd = pollrec->fd->fd;
2780 /* In direct contradiction to the Unix98 spec, IRIX runs into
2781 * difficulty if you pass in POLLERR, POLLHUP or POLLNVAL
2782 * flags in the events field of the pollfd while it should
2783 * just ignoring them. So we mask them out here.
2785 fds[n_poll].events = pollrec->fd->events & ~(G_IO_ERR|G_IO_HUP|G_IO_NVAL);
2786 fds[n_poll].revents = 0;
2789 pollrec = pollrec->next;
2793 context->poll_changed = FALSE;
2797 *timeout = context->timeout;
2800 context->time_is_fresh = FALSE;
2801 context->real_time_is_fresh = FALSE;
2805 UNLOCK_CONTEXT (context);
2811 * g_main_context_check:
2812 * @context: a #GMainContext
2813 * @max_priority: the maximum numerical priority of sources to check
2814 * @fds: (array length=n_fds): array of #GPollFD's that was passed to
2815 * the last call to g_main_context_query()
2816 * @n_fds: return value of g_main_context_query()
2818 * Passes the results of polling back to the main loop.
2820 * Return value: %TRUE if some sources are ready to be dispatched.
2823 g_main_context_check (GMainContext *context,
2833 LOCK_CONTEXT (context);
2835 if (context->in_check_or_prepare)
2837 g_warning ("g_main_context_check() called recursively from within a source's check() or "
2838 "prepare() member.");
2839 UNLOCK_CONTEXT (context);
2843 if (context->wake_up_rec.events)
2844 g_wakeup_acknowledge (context->wakeup);
2846 context->poll_waiting = FALSE;
2848 /* If the set of poll file descriptors changed, bail out
2849 * and let the main loop rerun
2851 if (context->poll_changed)
2853 UNLOCK_CONTEXT (context);
2857 pollrec = context->poll_records;
2861 if (pollrec->fd->events)
2862 pollrec->fd->revents = fds[i].revents;
2864 pollrec = pollrec->next;
2868 source = next_valid_source (context, NULL);
2871 if ((n_ready > 0) && (source->priority > max_priority))
2873 SOURCE_UNREF (source, context);
2876 if (SOURCE_BLOCKED (source))
2879 if (!(source->flags & G_SOURCE_READY))
2882 gboolean (*check) (GSource *source);
2884 check = source->source_funcs->check;
2886 context->in_check_or_prepare++;
2887 UNLOCK_CONTEXT (context);
2889 result = (*check) (source);
2891 LOCK_CONTEXT (context);
2892 context->in_check_or_prepare--;
2896 GSource *ready_source = source;
2898 while (ready_source)
2900 ready_source->flags |= G_SOURCE_READY;
2901 ready_source = ready_source->priv ? ready_source->priv->parent_source : NULL;
2906 if (source->flags & G_SOURCE_READY)
2908 source->ref_count++;
2909 g_ptr_array_add (context->pending_dispatches, source);
2913 /* never dispatch sources with less priority than the first
2914 * one we choose to dispatch
2916 max_priority = source->priority;
2920 source = next_valid_source (context, source);
2923 UNLOCK_CONTEXT (context);
2929 * g_main_context_dispatch:
2930 * @context: a #GMainContext
2932 * Dispatches all pending sources.
2935 g_main_context_dispatch (GMainContext *context)
2937 LOCK_CONTEXT (context);
2939 if (context->pending_dispatches->len > 0)
2941 g_main_dispatch (context);
2944 UNLOCK_CONTEXT (context);
2947 /* HOLDS context lock */
2949 g_main_context_iterate (GMainContext *context,
2956 gboolean some_ready;
2957 gint nfds, allocated_nfds;
2958 GPollFD *fds = NULL;
2960 UNLOCK_CONTEXT (context);
2962 if (!g_main_context_acquire (context))
2964 gboolean got_ownership;
2966 LOCK_CONTEXT (context);
2972 context->cond = g_cond_new ();
2974 got_ownership = g_main_context_wait (context,
2976 g_static_mutex_get_mutex (&context->mutex));
2982 LOCK_CONTEXT (context);
2984 if (!context->cached_poll_array)
2986 context->cached_poll_array_size = context->n_poll_records;
2987 context->cached_poll_array = g_new (GPollFD, context->n_poll_records);
2990 allocated_nfds = context->cached_poll_array_size;
2991 fds = context->cached_poll_array;
2993 UNLOCK_CONTEXT (context);
2995 g_main_context_prepare (context, &max_priority);
2997 while ((nfds = g_main_context_query (context, max_priority, &timeout, fds,
2998 allocated_nfds)) > allocated_nfds)
3000 LOCK_CONTEXT (context);
3002 context->cached_poll_array_size = allocated_nfds = nfds;
3003 context->cached_poll_array = fds = g_new (GPollFD, nfds);
3004 UNLOCK_CONTEXT (context);
3010 g_main_context_poll (context, timeout, max_priority, fds, nfds);
3012 some_ready = g_main_context_check (context, max_priority, fds, nfds);
3015 g_main_context_dispatch (context);
3017 g_main_context_release (context);
3019 LOCK_CONTEXT (context);
3025 * g_main_context_pending:
3026 * @context: a #GMainContext (if %NULL, the default context will be used)
3028 * Checks if any sources have pending events for the given context.
3030 * Return value: %TRUE if events are pending.
3033 g_main_context_pending (GMainContext *context)
3038 context = g_main_context_default();
3040 LOCK_CONTEXT (context);
3041 retval = g_main_context_iterate (context, FALSE, FALSE, G_THREAD_SELF);
3042 UNLOCK_CONTEXT (context);
3048 * g_main_context_iteration:
3049 * @context: a #GMainContext (if %NULL, the default context will be used)
3050 * @may_block: whether the call may block.
3052 * Runs a single iteration for the given main loop. This involves
3053 * checking to see if any event sources are ready to be processed,
3054 * then if no events sources are ready and @may_block is %TRUE, waiting
3055 * for a source to become ready, then dispatching the highest priority
3056 * events sources that are ready. Otherwise, if @may_block is %FALSE
3057 * sources are not waited to become ready, only those highest priority
3058 * events sources will be dispatched (if any), that are ready at this
3059 * given moment without further waiting.
3061 * Note that even when @may_block is %TRUE, it is still possible for
3062 * g_main_context_iteration() to return %FALSE, since the the wait may
3063 * be interrupted for other reasons than an event source becoming ready.
3065 * Return value: %TRUE if events were dispatched.
3068 g_main_context_iteration (GMainContext *context, gboolean may_block)
3073 context = g_main_context_default();
3075 LOCK_CONTEXT (context);
3076 retval = g_main_context_iterate (context, may_block, TRUE, G_THREAD_SELF);
3077 UNLOCK_CONTEXT (context);
3084 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used).
3085 * @is_running: set to %TRUE to indicate that the loop is running. This
3086 * is not very important since calling g_main_loop_run() will set this to
3089 * Creates a new #GMainLoop structure.
3091 * Return value: a new #GMainLoop.
3094 g_main_loop_new (GMainContext *context,
3095 gboolean is_running)
3100 context = g_main_context_default();
3102 g_main_context_ref (context);
3104 loop = g_new0 (GMainLoop, 1);
3105 loop->context = context;
3106 loop->is_running = is_running != FALSE;
3107 loop->ref_count = 1;
3114 * @loop: a #GMainLoop
3116 * Increases the reference count on a #GMainLoop object by one.
3118 * Return value: @loop
3121 g_main_loop_ref (GMainLoop *loop)
3123 g_return_val_if_fail (loop != NULL, NULL);
3124 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
3126 g_atomic_int_inc (&loop->ref_count);
3132 * g_main_loop_unref:
3133 * @loop: a #GMainLoop
3135 * Decreases the reference count on a #GMainLoop object by one. If
3136 * the result is zero, free the loop and free all associated memory.
3139 g_main_loop_unref (GMainLoop *loop)
3141 g_return_if_fail (loop != NULL);
3142 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3144 if (!g_atomic_int_dec_and_test (&loop->ref_count))
3147 g_main_context_unref (loop->context);
3153 * @loop: a #GMainLoop
3155 * Runs a main loop until g_main_loop_quit() is called on the loop.
3156 * If this is called for the thread of the loop's #GMainContext,
3157 * it will process events from the loop, otherwise it will
3161 g_main_loop_run (GMainLoop *loop)
3163 GThread *self = G_THREAD_SELF;
3165 g_return_if_fail (loop != NULL);
3166 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3168 if (!g_main_context_acquire (loop->context))
3170 gboolean got_ownership = FALSE;
3172 /* Another thread owns this context */
3173 LOCK_CONTEXT (loop->context);
3175 g_atomic_int_inc (&loop->ref_count);
3177 if (!loop->is_running)
3178 loop->is_running = TRUE;
3180 if (!loop->context->cond)
3181 loop->context->cond = g_cond_new ();
3183 while (loop->is_running && !got_ownership)
3184 got_ownership = g_main_context_wait (loop->context,
3185 loop->context->cond,
3186 g_static_mutex_get_mutex (&loop->context->mutex));
3188 if (!loop->is_running)
3190 UNLOCK_CONTEXT (loop->context);
3192 g_main_context_release (loop->context);
3193 g_main_loop_unref (loop);
3197 g_assert (got_ownership);
3200 LOCK_CONTEXT (loop->context);
3202 if (loop->context->in_check_or_prepare)
3204 g_warning ("g_main_loop_run(): called recursively from within a source's "
3205 "check() or prepare() member, iteration not possible.");
3209 g_atomic_int_inc (&loop->ref_count);
3210 loop->is_running = TRUE;
3211 while (loop->is_running)
3212 g_main_context_iterate (loop->context, TRUE, TRUE, self);
3214 UNLOCK_CONTEXT (loop->context);
3216 g_main_context_release (loop->context);
3218 g_main_loop_unref (loop);
3223 * @loop: a #GMainLoop
3225 * Stops a #GMainLoop from running. Any calls to g_main_loop_run()
3226 * for the loop will return.
3228 * Note that sources that have already been dispatched when
3229 * g_main_loop_quit() is called will still be executed.
3232 g_main_loop_quit (GMainLoop *loop)
3234 g_return_if_fail (loop != NULL);
3235 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3237 LOCK_CONTEXT (loop->context);
3238 loop->is_running = FALSE;
3239 g_main_context_wakeup_unlocked (loop->context);
3241 if (loop->context->cond)
3242 g_cond_broadcast (loop->context->cond);
3244 UNLOCK_CONTEXT (loop->context);
3248 * g_main_loop_is_running:
3249 * @loop: a #GMainLoop.
3251 * Checks to see if the main loop is currently being run via g_main_loop_run().
3253 * Return value: %TRUE if the mainloop is currently being run.
3256 g_main_loop_is_running (GMainLoop *loop)
3258 g_return_val_if_fail (loop != NULL, FALSE);
3259 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, FALSE);
3261 return loop->is_running;
3265 * g_main_loop_get_context:
3266 * @loop: a #GMainLoop.
3268 * Returns the #GMainContext of @loop.
3270 * Return value: (transfer none): the #GMainContext of @loop
3273 g_main_loop_get_context (GMainLoop *loop)
3275 g_return_val_if_fail (loop != NULL, NULL);
3276 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
3278 return loop->context;
3281 /* HOLDS: context's lock */
3283 g_main_context_poll (GMainContext *context,
3289 #ifdef G_MAIN_POLL_DEBUG
3295 GPollFunc poll_func;
3297 if (n_fds || timeout != 0)
3299 #ifdef G_MAIN_POLL_DEBUG
3300 if (_g_main_poll_debug)
3302 g_print ("polling context=%p n=%d timeout=%d\n",
3303 context, n_fds, timeout);
3304 poll_timer = g_timer_new ();
3308 LOCK_CONTEXT (context);
3310 poll_func = context->poll_func;
3312 UNLOCK_CONTEXT (context);
3313 if ((*poll_func) (fds, n_fds, timeout) < 0 && errno != EINTR)
3316 g_warning ("poll(2) failed due to: %s.",
3317 g_strerror (errno));
3319 /* If g_poll () returns -1, it has already called g_warning() */
3323 #ifdef G_MAIN_POLL_DEBUG
3324 if (_g_main_poll_debug)
3326 LOCK_CONTEXT (context);
3328 g_print ("g_main_poll(%d) timeout: %d - elapsed %12.10f seconds",
3331 g_timer_elapsed (poll_timer, NULL));
3332 g_timer_destroy (poll_timer);
3333 pollrec = context->poll_records;
3335 while (pollrec != NULL)
3340 if (fds[i].fd == pollrec->fd->fd &&
3341 pollrec->fd->events &&
3344 g_print (" [" G_POLLFD_FORMAT " :", fds[i].fd);
3345 if (fds[i].revents & G_IO_IN)
3347 if (fds[i].revents & G_IO_OUT)
3349 if (fds[i].revents & G_IO_PRI)
3351 if (fds[i].revents & G_IO_ERR)
3353 if (fds[i].revents & G_IO_HUP)
3355 if (fds[i].revents & G_IO_NVAL)
3361 pollrec = pollrec->next;
3365 UNLOCK_CONTEXT (context);
3368 } /* if (n_fds || timeout != 0) */
3372 * g_main_context_add_poll:
3373 * @context: a #GMainContext (or %NULL for the default context)
3374 * @fd: a #GPollFD structure holding information about a file
3375 * descriptor to watch.
3376 * @priority: the priority for this file descriptor which should be
3377 * the same as the priority used for g_source_attach() to ensure that the
3378 * file descriptor is polled whenever the results may be needed.
3380 * Adds a file descriptor to the set of file descriptors polled for
3381 * this context. This will very seldom be used directly. Instead
3382 * a typical event source will use g_source_add_poll() instead.
3385 g_main_context_add_poll (GMainContext *context,
3390 context = g_main_context_default ();
3392 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3393 g_return_if_fail (fd);
3395 LOCK_CONTEXT (context);
3396 g_main_context_add_poll_unlocked (context, priority, fd);
3397 UNLOCK_CONTEXT (context);
3400 /* HOLDS: main_loop_lock */
3402 g_main_context_add_poll_unlocked (GMainContext *context,
3406 GPollRec *prevrec, *nextrec;
3407 GPollRec *newrec = g_slice_new (GPollRec);
3409 /* This file descriptor may be checked before we ever poll */
3412 newrec->priority = priority;
3414 prevrec = context->poll_records_tail;
3416 while (prevrec && priority < prevrec->priority)
3419 prevrec = prevrec->prev;
3423 prevrec->next = newrec;
3425 context->poll_records = newrec;
3427 newrec->prev = prevrec;
3428 newrec->next = nextrec;
3431 nextrec->prev = newrec;
3433 context->poll_records_tail = newrec;
3435 context->n_poll_records++;
3437 context->poll_changed = TRUE;
3439 /* Now wake up the main loop if it is waiting in the poll() */
3440 g_main_context_wakeup_unlocked (context);
3444 * g_main_context_remove_poll:
3445 * @context:a #GMainContext
3446 * @fd: a #GPollFD descriptor previously added with g_main_context_add_poll()
3448 * Removes file descriptor from the set of file descriptors to be
3449 * polled for a particular context.
3452 g_main_context_remove_poll (GMainContext *context,
3456 context = g_main_context_default ();
3458 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3459 g_return_if_fail (fd);
3461 LOCK_CONTEXT (context);
3462 g_main_context_remove_poll_unlocked (context, fd);
3463 UNLOCK_CONTEXT (context);
3467 g_main_context_remove_poll_unlocked (GMainContext *context,
3470 GPollRec *pollrec, *prevrec, *nextrec;
3473 pollrec = context->poll_records;
3477 nextrec = pollrec->next;
3478 if (pollrec->fd == fd)
3480 if (prevrec != NULL)
3481 prevrec->next = nextrec;
3483 context->poll_records = nextrec;
3485 if (nextrec != NULL)
3486 nextrec->prev = prevrec;
3488 context->poll_records_tail = prevrec;
3490 g_slice_free (GPollRec, pollrec);
3492 context->n_poll_records--;
3499 context->poll_changed = TRUE;
3501 /* Now wake up the main loop if it is waiting in the poll() */
3502 g_main_context_wakeup_unlocked (context);
3506 * g_source_get_current_time:
3507 * @source: a #GSource
3508 * @timeval: #GTimeVal structure in which to store current time.
3510 * Gets the "current time" to be used when checking
3511 * this source. The advantage of calling this function over
3512 * calling g_get_current_time() directly is that when
3513 * checking multiple sources, GLib can cache a single value
3514 * instead of having to repeatedly get the system time.
3516 * Deprecated: 2.28: use g_source_get_time() instead
3519 g_source_get_current_time (GSource *source,
3522 GMainContext *context;
3524 g_return_if_fail (source->context != NULL);
3526 context = source->context;
3528 LOCK_CONTEXT (context);
3530 if (!context->real_time_is_fresh)
3532 context->real_time = g_get_real_time ();
3533 context->real_time_is_fresh = TRUE;
3536 timeval->tv_sec = context->real_time / 1000000;
3537 timeval->tv_usec = context->real_time % 1000000;
3539 UNLOCK_CONTEXT (context);
3543 * g_source_get_time:
3544 * @source: a #GSource
3546 * Gets the time to be used when checking this source. The advantage of
3547 * calling this function over calling g_get_monotonic_time() directly is
3548 * that when checking multiple sources, GLib can cache a single value
3549 * instead of having to repeatedly get the system monotonic time.
3551 * The time here is the system monotonic time, if available, or some
3552 * other reasonable alternative otherwise. See g_get_monotonic_time().
3554 * Returns: the monotonic time in microseconds
3559 g_source_get_time (GSource *source)
3561 GMainContext *context;
3564 g_return_val_if_fail (source->context != NULL, 0);
3566 context = source->context;
3568 LOCK_CONTEXT (context);
3570 if (!context->time_is_fresh)
3572 context->time = g_get_monotonic_time ();
3573 context->time_is_fresh = TRUE;
3576 result = context->time;
3578 UNLOCK_CONTEXT (context);
3584 * g_main_context_set_poll_func:
3585 * @context: a #GMainContext
3586 * @func: the function to call to poll all file descriptors
3588 * Sets the function to use to handle polling of file descriptors. It
3589 * will be used instead of the poll() system call
3590 * (or GLib's replacement function, which is used where
3591 * poll() isn't available).
3593 * This function could possibly be used to integrate the GLib event
3594 * loop with an external event loop.
3597 g_main_context_set_poll_func (GMainContext *context,
3601 context = g_main_context_default ();
3603 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3605 LOCK_CONTEXT (context);
3608 context->poll_func = func;
3610 context->poll_func = g_poll;
3612 UNLOCK_CONTEXT (context);
3616 * g_main_context_get_poll_func:
3617 * @context: a #GMainContext
3619 * Gets the poll function set by g_main_context_set_poll_func().
3621 * Return value: the poll function
3624 g_main_context_get_poll_func (GMainContext *context)
3629 context = g_main_context_default ();
3631 g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL);
3633 LOCK_CONTEXT (context);
3634 result = context->poll_func;
3635 UNLOCK_CONTEXT (context);
3641 _g_main_wake_up_all_contexts (void)
3645 /* We were woken up. Wake up all other contexts in all other threads */
3646 G_LOCK (main_context_list);
3647 for (list = main_context_list; list; list = list->next)
3649 GMainContext *context = list->data;
3651 LOCK_CONTEXT (context);
3652 g_main_context_wakeup_unlocked (context);
3653 UNLOCK_CONTEXT (context);
3655 G_UNLOCK (main_context_list);
3659 /* HOLDS: context's lock */
3660 /* Wake the main loop up from a poll() */
3662 g_main_context_wakeup_unlocked (GMainContext *context)
3664 if (context->poll_waiting)
3666 context->poll_waiting = FALSE;
3667 g_wakeup_signal (context->wakeup);
3672 * g_main_context_wakeup:
3673 * @context: a #GMainContext
3675 * If @context is currently waiting in a poll(), interrupt
3676 * the poll(), and continue the iteration process.
3679 g_main_context_wakeup (GMainContext *context)
3682 context = g_main_context_default ();
3684 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3686 LOCK_CONTEXT (context);
3687 g_main_context_wakeup_unlocked (context);
3688 UNLOCK_CONTEXT (context);
3692 * g_main_context_is_owner:
3693 * @context: a #GMainContext
3695 * Determines whether this thread holds the (recursive)
3696 * ownership of this #GMainContext. This is useful to
3697 * know before waiting on another thread that may be
3698 * blocking to get ownership of @context.
3700 * Returns: %TRUE if current thread is owner of @context.
3705 g_main_context_is_owner (GMainContext *context)
3710 context = g_main_context_default ();
3712 LOCK_CONTEXT (context);
3713 is_owner = context->owner == G_THREAD_SELF;
3714 UNLOCK_CONTEXT (context);
3722 g_timeout_set_expiration (GTimeoutSource *timeout_source,
3723 gint64 current_time)
3725 timeout_source->expiration = current_time +
3726 (guint64) timeout_source->interval * 1000;
3728 if (timeout_source->seconds)
3731 static gint timer_perturb = -1;
3733 if (timer_perturb == -1)
3736 * we want a per machine/session unique 'random' value; try the dbus
3737 * address first, that has a UUID in it. If there is no dbus, use the
3738 * hostname for hashing.
3740 const char *session_bus_address = g_getenv ("DBUS_SESSION_BUS_ADDRESS");
3741 if (!session_bus_address)
3742 session_bus_address = g_getenv ("HOSTNAME");
3743 if (session_bus_address)
3744 timer_perturb = ABS ((gint) g_str_hash (session_bus_address)) % 1000000;
3749 /* We want the microseconds part of the timeout to land on the
3750 * 'timer_perturb' mark, but we need to make sure we don't try to
3751 * set the timeout in the past. We do this by ensuring that we
3752 * always only *increase* the expiration time by adding a full
3753 * second in the case that the microsecond portion decreases.
3755 timeout_source->expiration -= timer_perturb;
3757 remainder = timeout_source->expiration % 1000000;
3758 if (remainder >= 1000000/4)
3759 timeout_source->expiration += 1000000;
3761 timeout_source->expiration -= remainder;
3762 timeout_source->expiration += timer_perturb;
3767 g_timeout_prepare (GSource *source,
3770 GTimeoutSource *timeout_source = (GTimeoutSource *) source;
3771 gint64 now = g_source_get_time (source);
3773 if (now < timeout_source->expiration)
3775 /* Round up to ensure that we don't try again too early */
3776 *timeout = (timeout_source->expiration - now + 999) / 1000;
3785 g_timeout_check (GSource *source)
3787 GTimeoutSource *timeout_source = (GTimeoutSource *) source;
3788 gint64 now = g_source_get_time (source);
3790 return timeout_source->expiration <= now;
3794 g_timeout_dispatch (GSource *source,
3795 GSourceFunc callback,
3798 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3803 g_warning ("Timeout source dispatched without callback\n"
3804 "You must call g_source_set_callback().");
3808 again = callback (user_data);
3811 g_timeout_set_expiration (timeout_source, g_source_get_time (source));
3817 * g_timeout_source_new:
3818 * @interval: the timeout interval in milliseconds.
3820 * Creates a new timeout source.
3822 * The source will not initially be associated with any #GMainContext
3823 * and must be added to one with g_source_attach() before it will be
3826 * The interval given is in terms of monotonic time, not wall clock
3827 * time. See g_get_monotonic_time().
3829 * Return value: the newly-created timeout source
3832 g_timeout_source_new (guint interval)
3834 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
3835 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3837 timeout_source->interval = interval;
3838 g_timeout_set_expiration (timeout_source, g_get_monotonic_time ());
3844 * g_timeout_source_new_seconds:
3845 * @interval: the timeout interval in seconds
3847 * Creates a new timeout source.
3849 * The source will not initially be associated with any #GMainContext
3850 * and must be added to one with g_source_attach() before it will be
3853 * The scheduling granularity/accuracy of this timeout source will be
3856 * The interval given in terms of monotonic time, not wall clock time.
3857 * See g_get_monotonic_time().
3859 * Return value: the newly-created timeout source
3864 g_timeout_source_new_seconds (guint interval)
3866 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
3867 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3869 timeout_source->interval = 1000 * interval;
3870 timeout_source->seconds = TRUE;
3872 g_timeout_set_expiration (timeout_source, g_get_monotonic_time ());
3879 * g_timeout_add_full:
3880 * @priority: the priority of the timeout source. Typically this will be in
3881 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
3882 * @interval: the time between calls to the function, in milliseconds
3883 * (1/1000ths of a second)
3884 * @function: function to call
3885 * @data: data to pass to @function
3886 * @notify: function to call when the timeout is removed, or %NULL
3888 * Sets a function to be called at regular intervals, with the given
3889 * priority. The function is called repeatedly until it returns
3890 * %FALSE, at which point the timeout is automatically destroyed and
3891 * the function will not be called again. The @notify function is
3892 * called when the timeout is destroyed. The first call to the
3893 * function will be at the end of the first @interval.
3895 * Note that timeout functions may be delayed, due to the processing of other
3896 * event sources. Thus they should not be relied on for precise timing.
3897 * After each call to the timeout function, the time of the next
3898 * timeout is recalculated based on the current time and the given interval
3899 * (it does not try to 'catch up' time lost in delays).
3901 * This internally creates a main loop source using g_timeout_source_new()
3902 * and attaches it to the main loop context using g_source_attach(). You can
3903 * do these steps manually if you need greater control.
3905 * The interval given in terms of monotonic time, not wall clock time.
3906 * See g_get_monotonic_time().
3908 * Return value: the ID (greater than 0) of the event source.
3909 * Rename to: g_timeout_add
3912 g_timeout_add_full (gint priority,
3914 GSourceFunc function,
3916 GDestroyNotify notify)
3921 g_return_val_if_fail (function != NULL, 0);
3923 source = g_timeout_source_new (interval);
3925 if (priority != G_PRIORITY_DEFAULT)
3926 g_source_set_priority (source, priority);
3928 g_source_set_callback (source, function, data, notify);
3929 id = g_source_attach (source, NULL);
3930 g_source_unref (source);
3937 * @interval: the time between calls to the function, in milliseconds
3938 * (1/1000ths of a second)
3939 * @function: function to call
3940 * @data: data to pass to @function
3942 * Sets a function to be called at regular intervals, with the default
3943 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly
3944 * until it returns %FALSE, at which point the timeout is automatically
3945 * destroyed and the function will not be called again. The first call
3946 * to the function will be at the end of the first @interval.
3948 * Note that timeout functions may be delayed, due to the processing of other
3949 * event sources. Thus they should not be relied on for precise timing.
3950 * After each call to the timeout function, the time of the next
3951 * timeout is recalculated based on the current time and the given interval
3952 * (it does not try to 'catch up' time lost in delays).
3954 * If you want to have a timer in the "seconds" range and do not care
3955 * about the exact time of the first call of the timer, use the
3956 * g_timeout_add_seconds() function; this function allows for more
3957 * optimizations and more efficient system power usage.
3959 * This internally creates a main loop source using g_timeout_source_new()
3960 * and attaches it to the main loop context using g_source_attach(). You can
3961 * do these steps manually if you need greater control.
3963 * The interval given is in terms of monotonic time, not wall clock
3964 * time. See g_get_monotonic_time().
3966 * Return value: the ID (greater than 0) of the event source.
3969 g_timeout_add (guint32 interval,
3970 GSourceFunc function,
3973 return g_timeout_add_full (G_PRIORITY_DEFAULT,
3974 interval, function, data, NULL);
3978 * g_timeout_add_seconds_full:
3979 * @priority: the priority of the timeout source. Typically this will be in
3980 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
3981 * @interval: the time between calls to the function, in seconds
3982 * @function: function to call
3983 * @data: data to pass to @function
3984 * @notify: function to call when the timeout is removed, or %NULL
3986 * Sets a function to be called at regular intervals, with @priority.
3987 * The function is called repeatedly until it returns %FALSE, at which
3988 * point the timeout is automatically destroyed and the function will
3989 * not be called again.
3991 * Unlike g_timeout_add(), this function operates at whole second granularity.
3992 * The initial starting point of the timer is determined by the implementation
3993 * and the implementation is expected to group multiple timers together so that
3994 * they fire all at the same time.
3995 * To allow this grouping, the @interval to the first timer is rounded
3996 * and can deviate up to one second from the specified interval.
3997 * Subsequent timer iterations will generally run at the specified interval.
3999 * Note that timeout functions may be delayed, due to the processing of other
4000 * event sources. Thus they should not be relied on for precise timing.
4001 * After each call to the timeout function, the time of the next
4002 * timeout is recalculated based on the current time and the given @interval
4004 * If you want timing more precise than whole seconds, use g_timeout_add()
4007 * The grouping of timers to fire at the same time results in a more power
4008 * and CPU efficient behavior so if your timer is in multiples of seconds
4009 * and you don't require the first timer exactly one second from now, the
4010 * use of g_timeout_add_seconds() is preferred over g_timeout_add().
4012 * This internally creates a main loop source using
4013 * g_timeout_source_new_seconds() and attaches it to the main loop context
4014 * using g_source_attach(). You can do these steps manually if you need
4017 * The interval given is in terms of monotonic time, not wall clock
4018 * time. See g_get_monotonic_time().
4020 * Return value: the ID (greater than 0) of the event source.
4022 * Rename to: g_timeout_add_seconds
4026 g_timeout_add_seconds_full (gint priority,
4028 GSourceFunc function,
4030 GDestroyNotify notify)
4035 g_return_val_if_fail (function != NULL, 0);
4037 source = g_timeout_source_new_seconds (interval);
4039 if (priority != G_PRIORITY_DEFAULT)
4040 g_source_set_priority (source, priority);
4042 g_source_set_callback (source, function, data, notify);
4043 id = g_source_attach (source, NULL);
4044 g_source_unref (source);
4050 * g_timeout_add_seconds:
4051 * @interval: the time between calls to the function, in seconds
4052 * @function: function to call
4053 * @data: data to pass to @function
4055 * Sets a function to be called at regular intervals with the default
4056 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly until
4057 * it returns %FALSE, at which point the timeout is automatically destroyed
4058 * and the function will not be called again.
4060 * This internally creates a main loop source using
4061 * g_timeout_source_new_seconds() and attaches it to the main loop context
4062 * using g_source_attach(). You can do these steps manually if you need
4063 * greater control. Also see g_timeout_add_seconds_full().
4065 * Note that the first call of the timer may not be precise for timeouts
4066 * of one second. If you need finer precision and have such a timeout,
4067 * you may want to use g_timeout_add() instead.
4069 * The interval given is in terms of monotonic time, not wall clock
4070 * time. See g_get_monotonic_time().
4072 * Return value: the ID (greater than 0) of the event source.
4077 g_timeout_add_seconds (guint interval,
4078 GSourceFunc function,
4081 g_return_val_if_fail (function != NULL, 0);
4083 return g_timeout_add_seconds_full (G_PRIORITY_DEFAULT, interval, function, data, NULL);
4086 /* Child watch functions */
4091 g_child_watch_prepare (GSource *source,
4100 g_child_watch_check (GSource *source)
4102 GChildWatchSource *child_watch_source;
4103 gboolean child_exited;
4105 child_watch_source = (GChildWatchSource *) source;
4107 child_exited = child_watch_source->poll.revents & G_IO_IN;
4114 * Note: We do _not_ check for the special value of STILL_ACTIVE
4115 * since we know that the process has exited and doing so runs into
4116 * problems if the child process "happens to return STILL_ACTIVE(259)"
4117 * as Microsoft's Platform SDK puts it.
4119 if (!GetExitCodeProcess (child_watch_source->pid, &child_status))
4121 gchar *emsg = g_win32_error_message (GetLastError ());
4122 g_warning (G_STRLOC ": GetExitCodeProcess() failed: %s", emsg);
4125 child_watch_source->child_status = -1;
4128 child_watch_source->child_status = child_status;
4131 return child_exited;
4134 #else /* G_OS_WIN32 */
4137 check_for_child_exited (GSource *source)
4139 GChildWatchSource *child_watch_source;
4142 /* protect against another SIGCHLD in the middle of this call */
4143 count = child_watch_count;
4145 child_watch_source = (GChildWatchSource *) source;
4147 if (child_watch_source->child_exited)
4150 if (child_watch_source->count < count)
4154 if (waitpid (child_watch_source->pid, &child_status, WNOHANG) > 0)
4156 child_watch_source->child_status = child_status;
4157 child_watch_source->child_exited = TRUE;
4159 child_watch_source->count = count;
4162 return child_watch_source->child_exited;
4166 g_child_watch_prepare (GSource *source,
4171 return check_for_child_exited (source);
4175 g_child_watch_check (GSource *source)
4177 return check_for_child_exited (source);
4181 check_for_signal_delivery (GSource *source)
4183 GUnixSignalWatchSource *unix_signal_source = (GUnixSignalWatchSource*) source;
4186 G_LOCK (unix_signal_lock);
4187 g_assert (unix_signal_initialized);
4188 delivered = unix_signal_source->pending;
4189 G_UNLOCK (unix_signal_lock);
4195 g_unix_signal_watch_prepare (GSource *source,
4200 return check_for_signal_delivery (source);
4204 g_unix_signal_watch_check (GSource *source)
4206 return check_for_signal_delivery (source);
4210 g_unix_signal_watch_dispatch (GSource *source,
4211 GSourceFunc callback,
4214 GUnixSignalWatchSource *unix_signal_source;
4216 unix_signal_source = (GUnixSignalWatchSource *) source;
4220 g_warning ("Unix signal source dispatched without callback\n"
4221 "You must call g_source_set_callback().");
4225 (callback) (user_data);
4227 G_LOCK (unix_signal_lock);
4228 g_assert (unix_signal_initialized);
4229 unix_signal_source->pending = FALSE;
4230 G_UNLOCK (unix_signal_lock);
4236 ensure_unix_signal_handler_installed_unlocked (int signum)
4238 struct sigaction action;
4239 GError *error = NULL;
4241 if (!unix_signal_initialized)
4243 sigemptyset (&unix_signal_mask);
4245 if (!g_unix_open_pipe (unix_signal_wake_up_pipe, FD_CLOEXEC, &error))
4246 g_error ("Cannot create UNIX signal wake up pipe: %s\n", error->message);
4247 g_unix_set_fd_nonblocking (unix_signal_wake_up_pipe[1], TRUE, NULL);
4249 /* We create a helper thread that polls on the wakeup pipe indefinitely */
4250 if (g_thread_create (unix_signal_helper_thread, NULL, FALSE, &error) == NULL)
4251 g_error ("Cannot create a thread to monitor UNIX signals: %s\n", error->message);
4253 unix_signal_initialized = TRUE;
4256 if (sigismember (&unix_signal_mask, signum))
4259 sigaddset (&unix_signal_mask, signum);
4261 action.sa_handler = g_unix_signal_handler;
4262 sigemptyset (&action.sa_mask);
4263 action.sa_flags = SA_RESTART | SA_NOCLDSTOP;
4264 sigaction (signum, &action, NULL);
4268 _g_main_create_unix_signal_watch (int signum)
4271 GUnixSignalWatchSource *unix_signal_source;
4273 source = g_source_new (&g_unix_signal_funcs, sizeof (GUnixSignalWatchSource));
4274 unix_signal_source = (GUnixSignalWatchSource *) source;
4276 unix_signal_source->signum = signum;
4277 unix_signal_source->pending = FALSE;
4279 G_LOCK (unix_signal_lock);
4280 ensure_unix_signal_handler_installed_unlocked (signum);
4281 unix_signal_watches = g_slist_prepend (unix_signal_watches, unix_signal_source);
4282 G_UNLOCK (unix_signal_lock);
4288 g_unix_signal_watch_finalize (GSource *source)
4290 G_LOCK (unix_signal_lock);
4291 unix_signal_watches = g_slist_remove (unix_signal_watches, source);
4292 G_UNLOCK (unix_signal_lock);
4295 #endif /* G_OS_WIN32 */
4298 g_child_watch_dispatch (GSource *source,
4299 GSourceFunc callback,
4302 GChildWatchSource *child_watch_source;
4303 GChildWatchFunc child_watch_callback = (GChildWatchFunc) callback;
4305 child_watch_source = (GChildWatchSource *) source;
4309 g_warning ("Child watch source dispatched without callback\n"
4310 "You must call g_source_set_callback().");
4314 (child_watch_callback) (child_watch_source->pid, child_watch_source->child_status, user_data);
4316 /* We never keep a child watch source around as the child is gone */
4323 g_unix_signal_handler (int signum)
4325 if (signum == SIGCHLD)
4326 child_watch_count ++;
4332 buf[0] = _UNIX_SIGNAL_PIPE_SIGCHLD_CHAR;
4335 buf[0] = _UNIX_SIGNAL_PIPE_SIGHUP_CHAR;
4338 buf[0] = _UNIX_SIGNAL_PIPE_SIGINT_CHAR;
4341 buf[0] = _UNIX_SIGNAL_PIPE_SIGTERM_CHAR;
4344 /* Shouldn't happen */
4348 write (unix_signal_wake_up_pipe[1], buf, 1);
4352 deliver_unix_signal (int signum)
4355 g_assert (signum == SIGHUP || signum == SIGINT || signum == SIGTERM);
4357 G_LOCK (unix_signal_lock);
4358 for (iter = unix_signal_watches; iter; iter = iter->next)
4360 GUnixSignalWatchSource *source = iter->data;
4362 if (source->signum != signum)
4365 source->pending = TRUE;
4367 G_UNLOCK (unix_signal_lock);
4371 * This thread is created whenever anything in GLib needs
4372 * to deal with UNIX signals; at present, just SIGCHLD
4373 * from g_child_watch_source_new().
4375 * Note: We could eventually make this thread a more public interface
4376 * and allow e.g. GDBus to use it instead of its own worker thread.
4379 unix_signal_helper_thread (gpointer data)
4384 ssize_t i, bytes_read;
4385 gboolean sigterm_received = FALSE;
4386 gboolean sigint_received = FALSE;
4387 gboolean sighup_received = FALSE;
4389 bytes_read = read (unix_signal_wake_up_pipe[0], b, sizeof (b));
4392 g_warning ("Failed to read from child watch wake up pipe: %s",
4394 /* Not much we can do here sanely; just wait a second and hope
4397 g_usleep (G_USEC_PER_SEC);
4400 for (i = 0; i < bytes_read; i++)
4404 case _UNIX_SIGNAL_PIPE_SIGCHLD_CHAR:
4405 /* The child watch source will call waitpid() in its
4406 * prepare() and check() methods; however, we don't
4407 * know which pid exited, so we need to wake up
4408 * all contexts. Note: actually we could get the pid
4409 * from the "siginfo_t" via the handler, but to pass
4410 * that info down the pipe would require a more structured
4411 * data stream (as opposed to a single byte).
4414 case _UNIX_SIGNAL_PIPE_SIGTERM_CHAR:
4415 sigterm_received = TRUE;
4417 case _UNIX_SIGNAL_PIPE_SIGHUP_CHAR:
4418 sighup_received = TRUE;
4420 case _UNIX_SIGNAL_PIPE_SIGINT_CHAR:
4421 sigint_received = TRUE;
4424 g_warning ("Invalid char '%c' read from child watch pipe", b[i]);
4428 if (sigterm_received)
4429 deliver_unix_signal (SIGTERM);
4430 if (sigint_received)
4431 deliver_unix_signal (SIGINT);
4432 if (sighup_received)
4433 deliver_unix_signal (SIGHUP);
4434 _g_main_wake_up_all_contexts ();
4439 g_child_watch_source_init (void)
4441 G_LOCK (unix_signal_lock);
4442 ensure_unix_signal_handler_installed_unlocked (SIGCHLD);
4443 G_UNLOCK (unix_signal_lock);
4446 #endif /* !G_OS_WIN32 */
4449 * g_child_watch_source_new:
4450 * @pid: process to watch. On POSIX the pid of a child process. On
4451 * Windows a handle for a process (which doesn't have to be a child).
4453 * Creates a new child_watch source.
4455 * The source will not initially be associated with any #GMainContext
4456 * and must be added to one with g_source_attach() before it will be
4459 * Note that child watch sources can only be used in conjunction with
4460 * <literal>g_spawn...</literal> when the %G_SPAWN_DO_NOT_REAP_CHILD
4463 * Note that on platforms where #GPid must be explicitly closed
4464 * (see g_spawn_close_pid()) @pid must not be closed while the
4465 * source is still active. Typically, you will want to call
4466 * g_spawn_close_pid() in the callback function for the source.
4468 * Note further that using g_child_watch_source_new() is not
4469 * compatible with calling <literal>waitpid(-1)</literal> in
4470 * the application. Calling waitpid() for individual pids will
4473 * Return value: the newly-created child watch source
4478 g_child_watch_source_new (GPid pid)
4480 GSource *source = g_source_new (&g_child_watch_funcs, sizeof (GChildWatchSource));
4481 GChildWatchSource *child_watch_source = (GChildWatchSource *)source;
4484 child_watch_source->poll.fd = (gintptr) pid;
4485 child_watch_source->poll.events = G_IO_IN;
4487 g_source_add_poll (source, &child_watch_source->poll);
4488 #else /* G_OS_WIN32 */
4489 g_child_watch_source_init ();
4490 #endif /* G_OS_WIN32 */
4492 child_watch_source->pid = pid;
4498 * g_child_watch_add_full:
4499 * @priority: the priority of the idle source. Typically this will be in the
4500 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
4501 * @pid: process to watch. On POSIX the pid of a child process. On
4502 * Windows a handle for a process (which doesn't have to be a child).
4503 * @function: function to call
4504 * @data: data to pass to @function
4505 * @notify: function to call when the idle is removed, or %NULL
4507 * Sets a function to be called when the child indicated by @pid
4508 * exits, at the priority @priority.
4510 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
4511 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
4512 * the spawn function for the child watching to work.
4514 * Note that on platforms where #GPid must be explicitly closed
4515 * (see g_spawn_close_pid()) @pid must not be closed while the
4516 * source is still active. Typically, you will want to call
4517 * g_spawn_close_pid() in the callback function for the source.
4519 * GLib supports only a single callback per process id.
4521 * This internally creates a main loop source using
4522 * g_child_watch_source_new() and attaches it to the main loop context
4523 * using g_source_attach(). You can do these steps manually if you
4524 * need greater control.
4526 * Return value: the ID (greater than 0) of the event source.
4528 * Rename to: g_child_watch_add
4532 g_child_watch_add_full (gint priority,
4534 GChildWatchFunc function,
4536 GDestroyNotify notify)
4541 g_return_val_if_fail (function != NULL, 0);
4543 source = g_child_watch_source_new (pid);
4545 if (priority != G_PRIORITY_DEFAULT)
4546 g_source_set_priority (source, priority);
4548 g_source_set_callback (source, (GSourceFunc) function, data, notify);
4549 id = g_source_attach (source, NULL);
4550 g_source_unref (source);
4556 * g_child_watch_add:
4557 * @pid: process id to watch. On POSIX the pid of a child process. On
4558 * Windows a handle for a process (which doesn't have to be a child).
4559 * @function: function to call
4560 * @data: data to pass to @function
4562 * Sets a function to be called when the child indicated by @pid
4563 * exits, at a default priority, #G_PRIORITY_DEFAULT.
4565 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
4566 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
4567 * the spawn function for the child watching to work.
4569 * Note that on platforms where #GPid must be explicitly closed
4570 * (see g_spawn_close_pid()) @pid must not be closed while the
4571 * source is still active. Typically, you will want to call
4572 * g_spawn_close_pid() in the callback function for the source.
4574 * GLib supports only a single callback per process id.
4576 * This internally creates a main loop source using
4577 * g_child_watch_source_new() and attaches it to the main loop context
4578 * using g_source_attach(). You can do these steps manually if you
4579 * need greater control.
4581 * Return value: the ID (greater than 0) of the event source.
4586 g_child_watch_add (GPid pid,
4587 GChildWatchFunc function,
4590 return g_child_watch_add_full (G_PRIORITY_DEFAULT, pid, function, data, NULL);
4594 /* Idle functions */
4597 g_idle_prepare (GSource *source,
4606 g_idle_check (GSource *source)
4612 g_idle_dispatch (GSource *source,
4613 GSourceFunc callback,
4618 g_warning ("Idle source dispatched without callback\n"
4619 "You must call g_source_set_callback().");
4623 return callback (user_data);
4627 * g_idle_source_new:
4629 * Creates a new idle source.
4631 * The source will not initially be associated with any #GMainContext
4632 * and must be added to one with g_source_attach() before it will be
4633 * executed. Note that the default priority for idle sources is
4634 * %G_PRIORITY_DEFAULT_IDLE, as compared to other sources which
4635 * have a default priority of %G_PRIORITY_DEFAULT.
4637 * Return value: the newly-created idle source
4640 g_idle_source_new (void)
4644 source = g_source_new (&g_idle_funcs, sizeof (GSource));
4645 g_source_set_priority (source, G_PRIORITY_DEFAULT_IDLE);
4652 * @priority: the priority of the idle source. Typically this will be in the
4653 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
4654 * @function: function to call
4655 * @data: data to pass to @function
4656 * @notify: function to call when the idle is removed, or %NULL
4658 * Adds a function to be called whenever there are no higher priority
4659 * events pending. If the function returns %FALSE it is automatically
4660 * removed from the list of event sources and will not be called again.
4662 * This internally creates a main loop source using g_idle_source_new()
4663 * and attaches it to the main loop context using g_source_attach().
4664 * You can do these steps manually if you need greater control.
4666 * Return value: the ID (greater than 0) of the event source.
4667 * Rename to: g_idle_add
4670 g_idle_add_full (gint priority,
4671 GSourceFunc function,
4673 GDestroyNotify notify)
4678 g_return_val_if_fail (function != NULL, 0);
4680 source = g_idle_source_new ();
4682 if (priority != G_PRIORITY_DEFAULT_IDLE)
4683 g_source_set_priority (source, priority);
4685 g_source_set_callback (source, function, data, notify);
4686 id = g_source_attach (source, NULL);
4687 g_source_unref (source);
4694 * @function: function to call
4695 * @data: data to pass to @function.
4697 * Adds a function to be called whenever there are no higher priority
4698 * events pending to the default main loop. The function is given the
4699 * default idle priority, #G_PRIORITY_DEFAULT_IDLE. If the function
4700 * returns %FALSE it is automatically removed from the list of event
4701 * sources and will not be called again.
4703 * This internally creates a main loop source using g_idle_source_new()
4704 * and attaches it to the main loop context using g_source_attach().
4705 * You can do these steps manually if you need greater control.
4707 * Return value: the ID (greater than 0) of the event source.
4710 g_idle_add (GSourceFunc function,
4713 return g_idle_add_full (G_PRIORITY_DEFAULT_IDLE, function, data, NULL);
4717 * g_idle_remove_by_data:
4718 * @data: the data for the idle source's callback.
4720 * Removes the idle function with the given data.
4722 * Return value: %TRUE if an idle source was found and removed.
4725 g_idle_remove_by_data (gpointer data)
4727 return g_source_remove_by_funcs_user_data (&g_idle_funcs, data);
4731 * g_main_context_invoke:
4732 * @context: (allow-none): a #GMainContext, or %NULL
4733 * @function: function to call
4734 * @data: data to pass to @function
4736 * Invokes a function in such a way that @context is owned during the
4737 * invocation of @function.
4739 * If @context is %NULL then the global default main context — as
4740 * returned by g_main_context_default() — is used.
4742 * If @context is owned by the current thread, @function is called
4743 * directly. Otherwise, if @context is the thread-default main context
4744 * of the current thread and g_main_context_acquire() succeeds, then
4745 * @function is called and g_main_context_release() is called
4748 * In any other case, an idle source is created to call @function and
4749 * that source is attached to @context (presumably to be run in another
4750 * thread). The idle source is attached with #G_PRIORITY_DEFAULT
4751 * priority. If you want a different priority, use
4752 * g_main_context_invoke_full().
4754 * Note that, as with normal idle functions, @function should probably
4755 * return %FALSE. If it returns %TRUE, it will be continuously run in a
4756 * loop (and may prevent this call from returning).
4761 g_main_context_invoke (GMainContext *context,
4762 GSourceFunc function,
4765 g_main_context_invoke_full (context,
4767 function, data, NULL);
4771 * g_main_context_invoke_full:
4772 * @context: (allow-none): a #GMainContext, or %NULL
4773 * @priority: the priority at which to run @function
4774 * @function: function to call
4775 * @data: data to pass to @function
4776 * @notify: a function to call when @data is no longer in use, or %NULL.
4778 * Invokes a function in such a way that @context is owned during the
4779 * invocation of @function.
4781 * This function is the same as g_main_context_invoke() except that it
4782 * lets you specify the priority incase @function ends up being
4783 * scheduled as an idle and also lets you give a #GDestroyNotify for @data.
4785 * @notify should not assume that it is called from any particular
4786 * thread or with any particular context acquired.
4791 g_main_context_invoke_full (GMainContext *context,
4793 GSourceFunc function,
4795 GDestroyNotify notify)
4797 g_return_if_fail (function != NULL);
4800 context = g_main_context_default ();
4802 if (g_main_context_is_owner (context))
4804 while (function (data));
4811 GMainContext *thread_default;
4813 thread_default = g_main_context_get_thread_default ();
4815 if (!thread_default)
4816 thread_default = g_main_context_default ();
4818 if (thread_default == context && g_main_context_acquire (context))
4820 while (function (data));
4822 g_main_context_release (context);
4831 source = g_idle_source_new ();
4832 g_source_set_priority (source, priority);
4833 g_source_set_callback (source, function, data, notify);
4834 g_source_attach (source, context);
4835 g_source_unref (source);
4841 glib_worker_main (gpointer data)
4843 LOCK_CONTEXT (glib_worker_context);
4846 g_main_context_iterate (glib_worker_context, TRUE, TRUE, G_THREAD_SELF);
4848 return NULL; /* worst GCC warning message ever... */
4852 glib_get_worker_context (void)
4856 g_thread_init_glib ();
4858 if (g_once_init_enter (&initialised))
4860 GError *error = NULL;
4862 glib_worker_context = g_main_context_new ();
4863 if (g_thread_create (glib_worker_main, NULL, FALSE, &error) == NULL)
4864 g_error ("Creating GLib worker thread failed: %s\n", error->message);
4866 g_once_init_leave (&initialised, TRUE);
4869 return glib_worker_context;