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"
54 #include <sys/eventfd.h>
59 #include <sys/types.h>
62 #ifdef HAVE_SYS_TIME_H
64 #endif /* HAVE_SYS_TIME_H */
67 #endif /* HAVE_UNISTD_H */
74 #endif /* G_OS_WIN32 */
77 #include <sys/socket.h>
79 #endif /* G_OS_BEOS */
84 #include "giochannel.h"
88 #include "gstrfuncs.h"
89 #include "gtestutils.h"
95 #ifdef G_MAIN_POLL_DEBUG
100 #include "gmain-internal.h"
101 #include "glib-private.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>
178 * On Unix, the GLib mainloop is incompatible with fork(). Any program
179 * using the mainloop must either exec() or exit() from the child
180 * without returning to the mainloop.
185 typedef struct _GTimeoutSource GTimeoutSource;
186 typedef struct _GChildWatchSource GChildWatchSource;
187 typedef struct _GUnixSignalWatchSource GUnixSignalWatchSource;
188 typedef struct _GPollRec GPollRec;
189 typedef struct _GSourceCallback GSourceCallback;
193 G_SOURCE_READY = 1 << G_HOOK_FLAG_USER_SHIFT,
194 G_SOURCE_CAN_RECURSE = 1 << (G_HOOK_FLAG_USER_SHIFT + 1),
195 G_SOURCE_BLOCKED = 1 << (G_HOOK_FLAG_USER_SHIFT + 2)
198 typedef struct _GMainWaiter GMainWaiter;
206 typedef struct _GMainDispatch GMainDispatch;
208 struct _GMainDispatch
211 GSList *dispatching_sources; /* stack of current sources */
214 #ifdef G_MAIN_POLL_DEBUG
215 gboolean _g_main_poll_debug = FALSE;
220 /* The following lock is used for both the list of sources
221 * and the list of poll records
231 GPtrArray *pending_dispatches;
232 gint timeout; /* Timeout for current iteration */
235 GSource *source_list;
236 gint in_check_or_prepare;
238 GPollRec *poll_records, *poll_records_tail;
239 guint n_poll_records;
240 GPollFD *cached_poll_array;
241 guint cached_poll_array_size;
247 /* Flag indicating whether the set of fd's changed during a poll */
248 gboolean poll_changed;
253 gboolean time_is_fresh;
256 struct _GSourceCallback
261 GDestroyNotify notify;
266 GMainContext *context;
271 struct _GTimeoutSource
279 struct _GChildWatchSource
286 #else /* G_OS_WIN32 */
287 gboolean child_exited;
288 #endif /* G_OS_WIN32 */
291 struct _GUnixSignalWatchSource
306 struct _GSourcePrivate
308 GSList *child_sources;
309 GSource *parent_source;
312 #define LOCK_CONTEXT(context) g_mutex_lock (&context->mutex)
313 #define UNLOCK_CONTEXT(context) g_mutex_unlock (&context->mutex)
314 #define G_THREAD_SELF g_thread_self ()
316 #define SOURCE_DESTROYED(source) (((source)->flags & G_HOOK_FLAG_ACTIVE) == 0)
317 #define SOURCE_BLOCKED(source) (((source)->flags & G_SOURCE_BLOCKED) != 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,
350 static gboolean g_timeout_prepare (GSource *source,
352 static gboolean g_timeout_check (GSource *source);
353 static gboolean g_timeout_dispatch (GSource *source,
354 GSourceFunc callback,
356 static gboolean g_child_watch_prepare (GSource *source,
358 static gboolean g_child_watch_check (GSource *source);
359 static gboolean g_child_watch_dispatch (GSource *source,
360 GSourceFunc callback,
362 static void g_child_watch_finalize (GSource *source);
364 static void g_unix_signal_handler (int signum);
365 static gboolean g_unix_signal_watch_prepare (GSource *source,
367 static gboolean g_unix_signal_watch_check (GSource *source);
368 static gboolean g_unix_signal_watch_dispatch (GSource *source,
369 GSourceFunc callback,
371 static void g_unix_signal_watch_finalize (GSource *source);
373 static gboolean g_idle_prepare (GSource *source,
375 static gboolean g_idle_check (GSource *source);
376 static gboolean g_idle_dispatch (GSource *source,
377 GSourceFunc callback,
380 static GMainContext *glib_worker_context;
382 G_LOCK_DEFINE_STATIC (main_loop);
383 static GMainContext *default_main_context;
388 /* UNIX signals work by marking one of these variables then waking the
389 * worker context to check on them and dispatch accordingly.
391 #ifdef HAVE_SIG_ATOMIC_T
392 static volatile sig_atomic_t unix_signal_pending[NSIG];
393 static volatile sig_atomic_t any_unix_signal_pending;
395 static volatile int unix_signal_pending[NSIG];
396 static volatile int any_unix_signal_pending;
399 /* Guards all the data below */
400 G_LOCK_DEFINE_STATIC (unix_signal_lock);
401 static GSList *unix_signal_watches;
402 static GSList *unix_child_watches;
404 static GSourceFuncs g_unix_signal_funcs =
406 g_unix_signal_watch_prepare,
407 g_unix_signal_watch_check,
408 g_unix_signal_watch_dispatch,
409 g_unix_signal_watch_finalize
411 #endif /* !G_OS_WIN32 */
412 G_LOCK_DEFINE_STATIC (main_context_list);
413 static GSList *main_context_list = NULL;
415 GSourceFuncs g_timeout_funcs =
423 GSourceFuncs g_child_watch_funcs =
425 g_child_watch_prepare,
427 g_child_watch_dispatch,
428 g_child_watch_finalize
431 GSourceFuncs g_idle_funcs =
440 * g_main_context_ref:
441 * @context: a #GMainContext
443 * Increases the reference count on a #GMainContext object by one.
445 * Returns: the @context that was passed in (since 2.6)
448 g_main_context_ref (GMainContext *context)
450 g_return_val_if_fail (context != NULL, NULL);
451 g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL);
453 g_atomic_int_inc (&context->ref_count);
459 poll_rec_list_free (GMainContext *context,
462 g_slice_free_chain (GPollRec, list, next);
466 * g_main_context_unref:
467 * @context: a #GMainContext
469 * Decreases the reference count on a #GMainContext object by one. If
470 * the result is zero, free the context and free all associated memory.
473 g_main_context_unref (GMainContext *context)
476 g_return_if_fail (context != NULL);
477 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
479 if (!g_atomic_int_dec_and_test (&context->ref_count))
482 G_LOCK (main_context_list);
483 main_context_list = g_slist_remove (main_context_list, context);
484 G_UNLOCK (main_context_list);
486 source = context->source_list;
489 GSource *next = source->next;
490 g_source_destroy_internal (source, context, FALSE);
494 g_mutex_clear (&context->mutex);
496 g_ptr_array_free (context->pending_dispatches, TRUE);
497 g_free (context->cached_poll_array);
499 poll_rec_list_free (context, context->poll_records);
501 g_wakeup_free (context->wakeup);
502 g_cond_clear (&context->cond);
508 * g_main_context_new:
510 * Creates a new #GMainContext structure.
512 * Return value: the new #GMainContext
515 g_main_context_new (void)
517 static gsize initialised;
518 GMainContext *context;
520 if (g_once_init_enter (&initialised))
522 #ifdef G_MAIN_POLL_DEBUG
523 if (getenv ("G_MAIN_POLL_DEBUG") != NULL)
524 _g_main_poll_debug = TRUE;
527 g_once_init_leave (&initialised, TRUE);
530 context = g_new0 (GMainContext, 1);
532 g_mutex_init (&context->mutex);
533 g_cond_init (&context->cond);
535 context->owner = NULL;
536 context->waiters = NULL;
538 context->ref_count = 1;
540 context->next_id = 1;
542 context->source_list = NULL;
544 context->poll_func = g_poll;
546 context->cached_poll_array = NULL;
547 context->cached_poll_array_size = 0;
549 context->pending_dispatches = g_ptr_array_new ();
551 context->time_is_fresh = FALSE;
553 context->wakeup = g_wakeup_new ();
554 g_wakeup_get_pollfd (context->wakeup, &context->wake_up_rec);
555 g_main_context_add_poll_unlocked (context, 0, &context->wake_up_rec);
557 G_LOCK (main_context_list);
558 main_context_list = g_slist_append (main_context_list, context);
560 #ifdef G_MAIN_POLL_DEBUG
561 if (_g_main_poll_debug)
562 g_print ("created context=%p\n", context);
565 G_UNLOCK (main_context_list);
571 * g_main_context_default:
573 * Returns the global default main context. This is the main context
574 * used for main loop functions when a main loop is not explicitly
575 * specified, and corresponds to the "main" main loop. See also
576 * g_main_context_get_thread_default().
578 * Return value: (transfer none): the global default main context.
581 g_main_context_default (void)
587 if (!default_main_context)
589 default_main_context = g_main_context_new ();
590 #ifdef G_MAIN_POLL_DEBUG
591 if (_g_main_poll_debug)
592 g_print ("default context=%p\n", default_main_context);
596 G_UNLOCK (main_loop);
598 return default_main_context;
602 free_context (gpointer data)
604 GMainContext *context = data;
606 g_main_context_release (context);
608 g_main_context_unref (context);
612 free_context_stack (gpointer data)
614 g_queue_free_full((GQueue *) data, (GDestroyNotify) free_context);
617 static GPrivate thread_context_stack = G_PRIVATE_INIT (free_context_stack);
620 * g_main_context_push_thread_default:
621 * @context: (allow-none): a #GMainContext, or %NULL for the global default context
623 * Acquires @context and sets it as the thread-default context for the
624 * current thread. This will cause certain asynchronous operations
625 * (such as most <link linkend="gio">gio</link>-based I/O) which are
626 * started in this thread to run under @context and deliver their
627 * results to its main loop, rather than running under the global
628 * default context in the main thread. Note that calling this function
629 * changes the context returned by
630 * g_main_context_get_thread_default(), <emphasis>not</emphasis> the
631 * one returned by g_main_context_default(), so it does not affect the
632 * context used by functions like g_idle_add().
634 * Normally you would call this function shortly after creating a new
635 * thread, passing it a #GMainContext which will be run by a
636 * #GMainLoop in that thread, to set a new default context for all
637 * async operations in that thread. (In this case, you don't need to
638 * ever call g_main_context_pop_thread_default().) In some cases
639 * however, you may want to schedule a single operation in a
640 * non-default context, or temporarily use a non-default context in
641 * the main thread. In that case, you can wrap the call to the
642 * asynchronous operation inside a
643 * g_main_context_push_thread_default() /
644 * g_main_context_pop_thread_default() pair, but it is up to you to
645 * ensure that no other asynchronous operations accidentally get
646 * started while the non-default context is active.
648 * Beware that libraries that predate this function may not correctly
649 * handle being used from a thread with a thread-default context. Eg,
650 * see g_file_supports_thread_contexts().
655 g_main_context_push_thread_default (GMainContext *context)
658 gboolean acquired_context;
660 acquired_context = g_main_context_acquire (context);
661 g_return_if_fail (acquired_context);
663 if (context == g_main_context_default ())
666 g_main_context_ref (context);
668 stack = g_private_get (&thread_context_stack);
671 stack = g_queue_new ();
672 g_private_set (&thread_context_stack, stack);
675 g_queue_push_head (stack, context);
679 * g_main_context_pop_thread_default:
680 * @context: (allow-none): a #GMainContext object, or %NULL
682 * Pops @context off the thread-default context stack (verifying that
683 * it was on the top of the stack).
688 g_main_context_pop_thread_default (GMainContext *context)
692 if (context == g_main_context_default ())
695 stack = g_private_get (&thread_context_stack);
697 g_return_if_fail (stack != NULL);
698 g_return_if_fail (g_queue_peek_head (stack) == context);
700 g_queue_pop_head (stack);
702 g_main_context_release (context);
704 g_main_context_unref (context);
708 * g_main_context_get_thread_default:
710 * Gets the thread-default #GMainContext for this thread. Asynchronous
711 * operations that want to be able to be run in contexts other than
712 * the default one should call this method or
713 * g_main_context_ref_thread_default() to get a #GMainContext to add
714 * their #GSource<!-- -->s to. (Note that even in single-threaded
715 * programs applications may sometimes want to temporarily push a
716 * non-default context, so it is not safe to assume that this will
717 * always return %NULL if you are running in the default thread.)
719 * If you need to hold a reference on the context, use
720 * g_main_context_ref_thread_default() instead.
722 * Returns: (transfer none): the thread-default #GMainContext, or
723 * %NULL if the thread-default context is the global default context.
728 g_main_context_get_thread_default (void)
732 stack = g_private_get (&thread_context_stack);
734 return g_queue_peek_head (stack);
740 * g_main_context_ref_thread_default:
742 * Gets the thread-default #GMainContext for this thread, as with
743 * g_main_context_get_thread_default(), but also adds a reference to
744 * it with g_main_context_ref(). In addition, unlike
745 * g_main_context_get_thread_default(), if the thread-default context
746 * is the global default context, this will return that #GMainContext
747 * (with a ref added to it) rather than returning %NULL.
749 * Returns: (transfer full): the thread-default #GMainContext. Unref
750 * with g_main_context_unref() when you are done with it.
755 g_main_context_ref_thread_default (void)
757 GMainContext *context;
759 context = g_main_context_get_thread_default ();
761 context = g_main_context_default ();
762 return g_main_context_ref (context);
765 /* Hooks for adding to the main loop */
769 * @source_funcs: structure containing functions that implement
770 * the sources behavior.
771 * @struct_size: size of the #GSource structure to create.
773 * Creates a new #GSource structure. The size is specified to
774 * allow creating structures derived from #GSource that contain
775 * additional data. The size passed in must be at least
776 * <literal>sizeof (GSource)</literal>.
778 * The source will not initially be associated with any #GMainContext
779 * and must be added to one with g_source_attach() before it will be
782 * Return value: the newly-created #GSource.
785 g_source_new (GSourceFuncs *source_funcs,
790 g_return_val_if_fail (source_funcs != NULL, NULL);
791 g_return_val_if_fail (struct_size >= sizeof (GSource), NULL);
793 source = (GSource*) g_malloc0 (struct_size);
794 source->priv = g_slice_new0 (GSourcePrivate);
795 source->source_funcs = source_funcs;
796 source->ref_count = 1;
798 source->priority = G_PRIORITY_DEFAULT;
800 source->flags = G_HOOK_FLAG_ACTIVE;
802 /* NULL/0 initialization for all other fields */
807 /* Holds context's lock
810 g_source_list_add (GSource *source,
811 GMainContext *context)
813 GSource *prev, *next;
815 if (source->priv->parent_source)
817 /* Put the source immediately before its parent */
818 prev = source->priv->parent_source->prev;
819 next = source->priv->parent_source;
824 next = context->source_list;
825 while (next && next->priority <= source->priority)
840 context->source_list = source;
843 /* Holds context's lock
846 g_source_list_remove (GSource *source,
847 GMainContext *context)
850 source->prev->next = source->next;
852 context->source_list = source->next;
855 source->next->prev = source->prev;
862 g_source_attach_unlocked (GSource *source,
863 GMainContext *context)
868 source->context = context;
869 result = source->source_id = context->next_id++;
872 g_source_list_add (source, context);
874 tmp_list = source->poll_fds;
877 g_main_context_add_poll_unlocked (context, source->priority, tmp_list->data);
878 tmp_list = tmp_list->next;
881 tmp_list = source->priv->child_sources;
884 g_source_attach_unlocked (tmp_list->data, context);
885 tmp_list = tmp_list->next;
893 * @source: a #GSource
894 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
896 * Adds a #GSource to a @context so that it will be executed within
897 * that context. Remove it by calling g_source_destroy().
899 * Return value: the ID (greater than 0) for the source within the
903 g_source_attach (GSource *source,
904 GMainContext *context)
908 g_return_val_if_fail (source->context == NULL, 0);
909 g_return_val_if_fail (!SOURCE_DESTROYED (source), 0);
912 context = g_main_context_default ();
914 LOCK_CONTEXT (context);
916 result = g_source_attach_unlocked (source, context);
918 /* If another thread has acquired the context, wake it up since it
919 * might be in poll() right now.
921 if (context->owner && context->owner != G_THREAD_SELF)
922 g_wakeup_signal (context->wakeup);
924 UNLOCK_CONTEXT (context);
930 g_source_destroy_internal (GSource *source,
931 GMainContext *context,
935 LOCK_CONTEXT (context);
937 if (!SOURCE_DESTROYED (source))
940 gpointer old_cb_data;
941 GSourceCallbackFuncs *old_cb_funcs;
943 source->flags &= ~G_HOOK_FLAG_ACTIVE;
945 old_cb_data = source->callback_data;
946 old_cb_funcs = source->callback_funcs;
948 source->callback_data = NULL;
949 source->callback_funcs = NULL;
953 UNLOCK_CONTEXT (context);
954 old_cb_funcs->unref (old_cb_data);
955 LOCK_CONTEXT (context);
958 if (!SOURCE_BLOCKED (source))
960 tmp_list = source->poll_fds;
963 g_main_context_remove_poll_unlocked (context, tmp_list->data);
964 tmp_list = tmp_list->next;
968 if (source->priv->child_sources)
970 /* This is safe because even if a child_source finalizer or
971 * closure notify tried to modify source->priv->child_sources
972 * from outside the lock, it would fail since
973 * SOURCE_DESTROYED(source) is now TRUE.
975 tmp_list = source->priv->child_sources;
978 g_source_destroy_internal (tmp_list->data, context, TRUE);
979 g_source_unref_internal (tmp_list->data, context, TRUE);
980 tmp_list = tmp_list->next;
982 g_slist_free (source->priv->child_sources);
983 source->priv->child_sources = NULL;
986 g_source_unref_internal (source, context, TRUE);
990 UNLOCK_CONTEXT (context);
995 * @source: a #GSource
997 * Removes a source from its #GMainContext, if any, and mark it as
998 * destroyed. The source cannot be subsequently added to another
1002 g_source_destroy (GSource *source)
1004 GMainContext *context;
1006 g_return_if_fail (source != NULL);
1008 context = source->context;
1011 g_source_destroy_internal (source, context, FALSE);
1013 source->flags &= ~G_HOOK_FLAG_ACTIVE;
1018 * @source: a #GSource
1020 * Returns the numeric ID for a particular source. The ID of a source
1021 * is a positive integer which is unique within a particular main loop
1022 * context. The reverse
1023 * mapping from ID to source is done by g_main_context_find_source_by_id().
1025 * Return value: the ID (greater than 0) for the source
1028 g_source_get_id (GSource *source)
1032 g_return_val_if_fail (source != NULL, 0);
1033 g_return_val_if_fail (source->context != NULL, 0);
1035 LOCK_CONTEXT (source->context);
1036 result = source->source_id;
1037 UNLOCK_CONTEXT (source->context);
1043 * g_source_get_context:
1044 * @source: a #GSource
1046 * Gets the #GMainContext with which the source is associated.
1047 * Calling this function on a destroyed source is an error.
1049 * Return value: (transfer none) (allow-none): the #GMainContext with which the
1050 * source is associated, or %NULL if the context has not
1051 * yet been added to a source.
1054 g_source_get_context (GSource *source)
1056 g_return_val_if_fail (!SOURCE_DESTROYED (source), NULL);
1058 return source->context;
1062 * g_source_add_poll:
1063 * @source:a #GSource
1064 * @fd: a #GPollFD structure holding information about a file
1065 * descriptor to watch.
1067 * Adds a file descriptor to the set of file descriptors polled for
1068 * this source. This is usually combined with g_source_new() to add an
1069 * event source. The event source's check function will typically test
1070 * the @revents field in the #GPollFD struct and return %TRUE if events need
1074 g_source_add_poll (GSource *source,
1077 GMainContext *context;
1079 g_return_if_fail (source != NULL);
1080 g_return_if_fail (fd != NULL);
1081 g_return_if_fail (!SOURCE_DESTROYED (source));
1083 context = source->context;
1086 LOCK_CONTEXT (context);
1088 source->poll_fds = g_slist_prepend (source->poll_fds, fd);
1092 if (!SOURCE_BLOCKED (source))
1093 g_main_context_add_poll_unlocked (context, source->priority, fd);
1094 UNLOCK_CONTEXT (context);
1099 * g_source_remove_poll:
1100 * @source:a #GSource
1101 * @fd: a #GPollFD structure previously passed to g_source_add_poll().
1103 * Removes a file descriptor from the set of file descriptors polled for
1107 g_source_remove_poll (GSource *source,
1110 GMainContext *context;
1112 g_return_if_fail (source != NULL);
1113 g_return_if_fail (fd != NULL);
1114 g_return_if_fail (!SOURCE_DESTROYED (source));
1116 context = source->context;
1119 LOCK_CONTEXT (context);
1121 source->poll_fds = g_slist_remove (source->poll_fds, fd);
1125 if (!SOURCE_BLOCKED (source))
1126 g_main_context_remove_poll_unlocked (context, fd);
1127 UNLOCK_CONTEXT (context);
1132 * g_source_add_child_source:
1133 * @source:a #GSource
1134 * @child_source: a second #GSource that @source should "poll"
1136 * Adds @child_source to @source as a "polled" source; when @source is
1137 * added to a #GMainContext, @child_source will be automatically added
1138 * with the same priority, when @child_source is triggered, it will
1139 * cause @source to dispatch (in addition to calling its own
1140 * callback), and when @source is destroyed, it will destroy
1141 * @child_source as well. (@source will also still be dispatched if
1142 * its own prepare/check functions indicate that it is ready.)
1144 * If you don't need @child_source to do anything on its own when it
1145 * triggers, you can call g_source_set_dummy_callback() on it to set a
1146 * callback that does nothing (except return %TRUE if appropriate).
1148 * @source will hold a reference on @child_source while @child_source
1149 * is attached to it.
1154 g_source_add_child_source (GSource *source,
1155 GSource *child_source)
1157 GMainContext *context;
1159 g_return_if_fail (source != NULL);
1160 g_return_if_fail (child_source != NULL);
1161 g_return_if_fail (!SOURCE_DESTROYED (source));
1162 g_return_if_fail (!SOURCE_DESTROYED (child_source));
1163 g_return_if_fail (child_source->context == NULL);
1164 g_return_if_fail (child_source->priv->parent_source == NULL);
1166 context = source->context;
1169 LOCK_CONTEXT (context);
1171 source->priv->child_sources = g_slist_prepend (source->priv->child_sources,
1172 g_source_ref (child_source));
1173 child_source->priv->parent_source = source;
1174 g_source_set_priority_unlocked (child_source, NULL, source->priority);
1178 UNLOCK_CONTEXT (context);
1179 g_source_attach (child_source, context);
1184 * g_source_remove_child_source:
1185 * @source:a #GSource
1186 * @child_source: a #GSource previously passed to
1187 * g_source_add_child_source().
1189 * Detaches @child_source from @source and destroys it.
1194 g_source_remove_child_source (GSource *source,
1195 GSource *child_source)
1197 GMainContext *context;
1199 g_return_if_fail (source != NULL);
1200 g_return_if_fail (child_source != NULL);
1201 g_return_if_fail (child_source->priv->parent_source == source);
1202 g_return_if_fail (!SOURCE_DESTROYED (source));
1203 g_return_if_fail (!SOURCE_DESTROYED (child_source));
1205 context = source->context;
1208 LOCK_CONTEXT (context);
1210 source->priv->child_sources = g_slist_remove (source->priv->child_sources, child_source);
1211 g_source_destroy_internal (child_source, context, TRUE);
1212 g_source_unref_internal (child_source, context, TRUE);
1215 UNLOCK_CONTEXT (context);
1219 * g_source_set_callback_indirect:
1220 * @source: the source
1221 * @callback_data: pointer to callback data "object"
1222 * @callback_funcs: functions for reference counting @callback_data
1223 * and getting the callback and data
1225 * Sets the callback function storing the data as a refcounted callback
1226 * "object". This is used internally. Note that calling
1227 * g_source_set_callback_indirect() assumes
1228 * an initial reference count on @callback_data, and thus
1229 * @callback_funcs->unref will eventually be called once more
1230 * than @callback_funcs->ref.
1233 g_source_set_callback_indirect (GSource *source,
1234 gpointer callback_data,
1235 GSourceCallbackFuncs *callback_funcs)
1237 GMainContext *context;
1238 gpointer old_cb_data;
1239 GSourceCallbackFuncs *old_cb_funcs;
1241 g_return_if_fail (source != NULL);
1242 g_return_if_fail (callback_funcs != NULL || callback_data == NULL);
1244 context = source->context;
1247 LOCK_CONTEXT (context);
1249 old_cb_data = source->callback_data;
1250 old_cb_funcs = source->callback_funcs;
1252 source->callback_data = callback_data;
1253 source->callback_funcs = callback_funcs;
1256 UNLOCK_CONTEXT (context);
1259 old_cb_funcs->unref (old_cb_data);
1263 g_source_callback_ref (gpointer cb_data)
1265 GSourceCallback *callback = cb_data;
1267 callback->ref_count++;
1272 g_source_callback_unref (gpointer cb_data)
1274 GSourceCallback *callback = cb_data;
1276 callback->ref_count--;
1277 if (callback->ref_count == 0)
1279 if (callback->notify)
1280 callback->notify (callback->data);
1286 g_source_callback_get (gpointer cb_data,
1291 GSourceCallback *callback = cb_data;
1293 *func = callback->func;
1294 *data = callback->data;
1297 static GSourceCallbackFuncs g_source_callback_funcs = {
1298 g_source_callback_ref,
1299 g_source_callback_unref,
1300 g_source_callback_get,
1304 * g_source_set_callback:
1305 * @source: the source
1306 * @func: a callback function
1307 * @data: the data to pass to callback function
1308 * @notify: (allow-none): a function to call when @data is no longer in use, or %NULL.
1310 * Sets the callback function for a source. The callback for a source is
1311 * called from the source's dispatch function.
1313 * The exact type of @func depends on the type of source; ie. you
1314 * should not count on @func being called with @data as its first
1317 * Typically, you won't use this function. Instead use functions specific
1318 * to the type of source you are using.
1321 g_source_set_callback (GSource *source,
1324 GDestroyNotify notify)
1326 GSourceCallback *new_callback;
1328 g_return_if_fail (source != NULL);
1330 new_callback = g_new (GSourceCallback, 1);
1332 new_callback->ref_count = 1;
1333 new_callback->func = func;
1334 new_callback->data = data;
1335 new_callback->notify = notify;
1337 g_source_set_callback_indirect (source, new_callback, &g_source_callback_funcs);
1342 * g_source_set_funcs:
1343 * @source: a #GSource
1344 * @funcs: the new #GSourceFuncs
1346 * Sets the source functions (can be used to override
1347 * default implementations) of an unattached source.
1352 g_source_set_funcs (GSource *source,
1353 GSourceFuncs *funcs)
1355 g_return_if_fail (source != NULL);
1356 g_return_if_fail (source->context == NULL);
1357 g_return_if_fail (source->ref_count > 0);
1358 g_return_if_fail (funcs != NULL);
1360 source->source_funcs = funcs;
1364 g_source_set_priority_unlocked (GSource *source,
1365 GMainContext *context,
1370 g_return_if_fail (source->priv->parent_source == NULL ||
1371 source->priv->parent_source->priority == priority);
1373 source->priority = priority;
1377 /* Remove the source from the context's source and then
1378 * add it back so it is sorted in the correct place
1380 g_source_list_remove (source, source->context);
1381 g_source_list_add (source, source->context);
1383 if (!SOURCE_BLOCKED (source))
1385 tmp_list = source->poll_fds;
1388 g_main_context_remove_poll_unlocked (context, tmp_list->data);
1389 g_main_context_add_poll_unlocked (context, priority, tmp_list->data);
1391 tmp_list = tmp_list->next;
1396 if (source->priv->child_sources)
1398 tmp_list = source->priv->child_sources;
1401 g_source_set_priority_unlocked (tmp_list->data, context, priority);
1402 tmp_list = tmp_list->next;
1408 * g_source_set_priority:
1409 * @source: a #GSource
1410 * @priority: the new priority.
1412 * Sets the priority of a source. While the main loop is being run, a
1413 * source will be dispatched if it is ready to be dispatched and no
1414 * sources at a higher (numerically smaller) priority are ready to be
1418 g_source_set_priority (GSource *source,
1421 GMainContext *context;
1423 g_return_if_fail (source != NULL);
1425 context = source->context;
1428 LOCK_CONTEXT (context);
1429 g_source_set_priority_unlocked (source, context, priority);
1431 UNLOCK_CONTEXT (source->context);
1435 * g_source_get_priority:
1436 * @source: a #GSource
1438 * Gets the priority of a source.
1440 * Return value: the priority of the source
1443 g_source_get_priority (GSource *source)
1445 g_return_val_if_fail (source != NULL, 0);
1447 return source->priority;
1451 * g_source_set_can_recurse:
1452 * @source: a #GSource
1453 * @can_recurse: whether recursion is allowed for this source
1455 * Sets whether a source can be called recursively. If @can_recurse is
1456 * %TRUE, then while the source is being dispatched then this source
1457 * will be processed normally. Otherwise, all processing of this
1458 * source is blocked until the dispatch function returns.
1461 g_source_set_can_recurse (GSource *source,
1462 gboolean can_recurse)
1464 GMainContext *context;
1466 g_return_if_fail (source != NULL);
1468 context = source->context;
1471 LOCK_CONTEXT (context);
1474 source->flags |= G_SOURCE_CAN_RECURSE;
1476 source->flags &= ~G_SOURCE_CAN_RECURSE;
1479 UNLOCK_CONTEXT (context);
1483 * g_source_get_can_recurse:
1484 * @source: a #GSource
1486 * Checks whether a source is allowed to be called recursively.
1487 * see g_source_set_can_recurse().
1489 * Return value: whether recursion is allowed.
1492 g_source_get_can_recurse (GSource *source)
1494 g_return_val_if_fail (source != NULL, FALSE);
1496 return (source->flags & G_SOURCE_CAN_RECURSE) != 0;
1501 * g_source_set_name:
1502 * @source: a #GSource
1503 * @name: debug name for the source
1505 * Sets a name for the source, used in debugging and profiling.
1506 * The name defaults to #NULL.
1508 * The source name should describe in a human-readable way
1509 * what the source does. For example, "X11 event queue"
1510 * or "GTK+ repaint idle handler" or whatever it is.
1512 * It is permitted to call this function multiple times, but is not
1513 * recommended due to the potential performance impact. For example,
1514 * one could change the name in the "check" function of a #GSourceFuncs
1515 * to include details like the event type in the source name.
1520 g_source_set_name (GSource *source,
1523 g_return_if_fail (source != NULL);
1525 /* setting back to NULL is allowed, just because it's
1526 * weird if get_name can return NULL but you can't
1530 g_free (source->name);
1531 source->name = g_strdup (name);
1535 * g_source_get_name:
1536 * @source: a #GSource
1538 * Gets a name for the source, used in debugging and profiling.
1539 * The name may be #NULL if it has never been set with
1540 * g_source_set_name().
1542 * Return value: the name of the source
1546 g_source_get_name (GSource *source)
1548 g_return_val_if_fail (source != NULL, NULL);
1550 return source->name;
1554 * g_source_set_name_by_id:
1555 * @tag: a #GSource ID
1556 * @name: debug name for the source
1558 * Sets the name of a source using its ID.
1560 * This is a convenience utility to set source names from the return
1561 * value of g_idle_add(), g_timeout_add(), etc.
1566 g_source_set_name_by_id (guint tag,
1571 g_return_if_fail (tag > 0);
1573 source = g_main_context_find_source_by_id (NULL, tag);
1577 g_source_set_name (source, name);
1583 * @source: a #GSource
1585 * Increases the reference count on a source by one.
1587 * Return value: @source
1590 g_source_ref (GSource *source)
1592 GMainContext *context;
1594 g_return_val_if_fail (source != NULL, NULL);
1596 context = source->context;
1599 LOCK_CONTEXT (context);
1601 source->ref_count++;
1604 UNLOCK_CONTEXT (context);
1609 /* g_source_unref() but possible to call within context lock
1612 g_source_unref_internal (GSource *source,
1613 GMainContext *context,
1616 gpointer old_cb_data = NULL;
1617 GSourceCallbackFuncs *old_cb_funcs = NULL;
1619 g_return_if_fail (source != NULL);
1621 if (!have_lock && context)
1622 LOCK_CONTEXT (context);
1624 source->ref_count--;
1625 if (source->ref_count == 0)
1627 old_cb_data = source->callback_data;
1628 old_cb_funcs = source->callback_funcs;
1630 source->callback_data = NULL;
1631 source->callback_funcs = NULL;
1635 if (!SOURCE_DESTROYED (source))
1636 g_warning (G_STRLOC ": ref_count == 0, but source was still attached to a context!");
1637 g_source_list_remove (source, context);
1640 if (source->source_funcs->finalize)
1643 UNLOCK_CONTEXT (context);
1644 source->source_funcs->finalize (source);
1646 LOCK_CONTEXT (context);
1649 g_free (source->name);
1650 source->name = NULL;
1652 g_slist_free (source->poll_fds);
1653 source->poll_fds = NULL;
1655 g_slice_free (GSourcePrivate, source->priv);
1656 source->priv = NULL;
1661 if (!have_lock && context)
1662 UNLOCK_CONTEXT (context);
1667 UNLOCK_CONTEXT (context);
1669 old_cb_funcs->unref (old_cb_data);
1672 LOCK_CONTEXT (context);
1678 * @source: a #GSource
1680 * Decreases the reference count of a source by one. If the
1681 * resulting reference count is zero the source and associated
1682 * memory will be destroyed.
1685 g_source_unref (GSource *source)
1687 g_return_if_fail (source != NULL);
1689 g_source_unref_internal (source, source->context, FALSE);
1693 * g_main_context_find_source_by_id:
1694 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
1695 * @source_id: the source ID, as returned by g_source_get_id().
1697 * Finds a #GSource given a pair of context and ID.
1699 * Return value: (transfer none): the #GSource if found, otherwise, %NULL
1702 g_main_context_find_source_by_id (GMainContext *context,
1707 g_return_val_if_fail (source_id > 0, NULL);
1709 if (context == NULL)
1710 context = g_main_context_default ();
1712 LOCK_CONTEXT (context);
1714 source = context->source_list;
1717 if (!SOURCE_DESTROYED (source) &&
1718 source->source_id == source_id)
1720 source = source->next;
1723 UNLOCK_CONTEXT (context);
1729 * g_main_context_find_source_by_funcs_user_data:
1730 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used).
1731 * @funcs: the @source_funcs passed to g_source_new().
1732 * @user_data: the user data from the callback.
1734 * Finds a source with the given source functions and user data. If
1735 * multiple sources exist with the same source function and user data,
1736 * the first one found will be returned.
1738 * Return value: (transfer none): the source, if one was found, otherwise %NULL
1741 g_main_context_find_source_by_funcs_user_data (GMainContext *context,
1742 GSourceFuncs *funcs,
1747 g_return_val_if_fail (funcs != NULL, NULL);
1749 if (context == NULL)
1750 context = g_main_context_default ();
1752 LOCK_CONTEXT (context);
1754 source = context->source_list;
1757 if (!SOURCE_DESTROYED (source) &&
1758 source->source_funcs == funcs &&
1759 source->callback_funcs)
1761 GSourceFunc callback;
1762 gpointer callback_data;
1764 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
1766 if (callback_data == user_data)
1769 source = source->next;
1772 UNLOCK_CONTEXT (context);
1778 * g_main_context_find_source_by_user_data:
1779 * @context: a #GMainContext
1780 * @user_data: the user_data for the callback.
1782 * Finds a source with the given user data for the callback. If
1783 * multiple sources exist with the same user data, the first
1784 * one found will be returned.
1786 * Return value: (transfer none): the source, if one was found, otherwise %NULL
1789 g_main_context_find_source_by_user_data (GMainContext *context,
1794 if (context == NULL)
1795 context = g_main_context_default ();
1797 LOCK_CONTEXT (context);
1799 source = context->source_list;
1802 if (!SOURCE_DESTROYED (source) &&
1803 source->callback_funcs)
1805 GSourceFunc callback;
1806 gpointer callback_data = NULL;
1808 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
1810 if (callback_data == user_data)
1813 source = source->next;
1816 UNLOCK_CONTEXT (context);
1823 * @tag: the ID of the source to remove.
1825 * Removes the source with the given id from the default main context.
1827 * a #GSource is given by g_source_get_id(), or will be returned by the
1828 * functions g_source_attach(), g_idle_add(), g_idle_add_full(),
1829 * g_timeout_add(), g_timeout_add_full(), g_child_watch_add(),
1830 * g_child_watch_add_full(), g_io_add_watch(), and g_io_add_watch_full().
1832 * See also g_source_destroy(). You must use g_source_destroy() for sources
1833 * added to a non-default main context.
1835 * Return value: %TRUE if the source was found and removed.
1838 g_source_remove (guint tag)
1842 g_return_val_if_fail (tag > 0, FALSE);
1844 source = g_main_context_find_source_by_id (NULL, tag);
1846 g_source_destroy (source);
1848 return source != NULL;
1852 * g_source_remove_by_user_data:
1853 * @user_data: the user_data for the callback.
1855 * Removes a source from the default main loop context given the user
1856 * data for the callback. If multiple sources exist with the same user
1857 * data, only one will be destroyed.
1859 * Return value: %TRUE if a source was found and removed.
1862 g_source_remove_by_user_data (gpointer user_data)
1866 source = g_main_context_find_source_by_user_data (NULL, user_data);
1869 g_source_destroy (source);
1877 * g_source_remove_by_funcs_user_data:
1878 * @funcs: The @source_funcs passed to g_source_new()
1879 * @user_data: the user data for the callback
1881 * Removes a source from the default main loop context given the
1882 * source functions and user data. If multiple sources exist with the
1883 * same source functions and user data, only one will be destroyed.
1885 * Return value: %TRUE if a source was found and removed.
1888 g_source_remove_by_funcs_user_data (GSourceFuncs *funcs,
1893 g_return_val_if_fail (funcs != NULL, FALSE);
1895 source = g_main_context_find_source_by_funcs_user_data (NULL, funcs, user_data);
1898 g_source_destroy (source);
1906 * g_get_current_time:
1907 * @result: #GTimeVal structure in which to store current time.
1909 * Equivalent to the UNIX gettimeofday() function, but portable.
1911 * You may find g_get_real_time() to be more convenient.
1914 g_get_current_time (GTimeVal *result)
1919 g_return_if_fail (result != NULL);
1921 /*this is required on alpha, there the timeval structs are int's
1922 not longs and a cast only would fail horribly*/
1923 gettimeofday (&r, NULL);
1924 result->tv_sec = r.tv_sec;
1925 result->tv_usec = r.tv_usec;
1930 g_return_if_fail (result != NULL);
1932 GetSystemTimeAsFileTime (&ft);
1933 memmove (&time64, &ft, sizeof (FILETIME));
1935 /* Convert from 100s of nanoseconds since 1601-01-01
1936 * to Unix epoch. Yes, this is Y2038 unsafe.
1938 time64 -= G_GINT64_CONSTANT (116444736000000000);
1941 result->tv_sec = time64 / 1000000;
1942 result->tv_usec = time64 % 1000000;
1949 * Queries the system wall-clock time.
1951 * This call is functionally equivalent to g_get_current_time() except
1952 * that the return value is often more convenient than dealing with a
1955 * You should only use this call if you are actually interested in the real
1956 * wall-clock time. g_get_monotonic_time() is probably more useful for
1957 * measuring intervals.
1959 * Returns: the number of microseconds since January 1, 1970 UTC.
1964 g_get_real_time (void)
1968 g_get_current_time (&tv);
1970 return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec;
1974 static ULONGLONG (*g_GetTickCount64) (void) = NULL;
1975 static guint32 g_win32_tick_epoch = 0;
1977 G_GNUC_INTERNAL void
1978 g_clock_win32_init (void)
1982 g_GetTickCount64 = NULL;
1983 kernel32 = GetModuleHandle ("KERNEL32.DLL");
1984 if (kernel32 != NULL)
1985 g_GetTickCount64 = (void *) GetProcAddress (kernel32, "GetTickCount64");
1986 g_win32_tick_epoch = ((guint32)GetTickCount()) >> 31;
1991 * g_get_monotonic_time:
1993 * Queries the system monotonic time, if available.
1995 * On POSIX systems with clock_gettime() and <literal>CLOCK_MONOTONIC</literal> this call
1996 * is a very shallow wrapper for that. Otherwise, we make a best effort
1997 * that probably involves returning the wall clock time (with at least
1998 * microsecond accuracy, subject to the limitations of the OS kernel).
2000 * It's important to note that POSIX <literal>CLOCK_MONOTONIC</literal> does
2001 * not count time spent while the machine is suspended.
2003 * On Windows, "limitations of the OS kernel" is a rather substantial
2004 * statement. Depending on the configuration of the system, the wall
2005 * clock time is updated as infrequently as 64 times a second (which
2006 * is approximately every 16ms). Also, on XP (but not on Vista or later)
2007 * the monotonic clock is locally monotonic, but may differ in exact
2008 * value between processes due to timer wrap handling.
2010 * Returns: the monotonic time, in microseconds
2015 g_get_monotonic_time (void)
2017 #ifdef HAVE_CLOCK_GETTIME
2018 /* librt clock_gettime() is our first choice */
2021 #ifdef CLOCK_MONOTONIC
2022 clock_gettime (CLOCK_MONOTONIC, &ts);
2024 clock_gettime (CLOCK_REALTIME, &ts);
2027 /* In theory monotonic time can have any epoch.
2029 * glib presently assumes the following:
2031 * 1) The epoch comes some time after the birth of Jesus of Nazareth, but
2032 * not more than 10000 years later.
2034 * 2) The current time also falls sometime within this range.
2036 * These two reasonable assumptions leave us with a maximum deviation from
2037 * the epoch of 10000 years, or 315569520000000000 seconds.
2039 * If we restrict ourselves to this range then the number of microseconds
2040 * will always fit well inside the constraints of a int64 (by a factor of
2043 * If you actually hit the following assertion, probably you should file a
2044 * bug against your operating system for being excessively silly.
2046 g_assert (G_GINT64_CONSTANT (-315569520000000000) < ts.tv_sec &&
2047 ts.tv_sec < G_GINT64_CONSTANT (315569520000000000));
2049 return (((gint64) ts.tv_sec) * 1000000) + (ts.tv_nsec / 1000);
2051 #elif defined (G_OS_WIN32)
2055 /* There are four sources for the monotonic time on Windows:
2057 * Three are based on a (1 msec accuracy, but only read periodically) clock chip:
2058 * - GetTickCount (GTC)
2059 * 32bit msec counter, updated each ~15msec, wraps in ~50 days
2060 * - GetTickCount64 (GTC64)
2061 * Same as GetTickCount, but extended to 64bit, so no wrap
2062 * Only available in Vista or later
2063 * - timeGetTime (TGT)
2064 * similar to GetTickCount by default: 15msec, 50 day wrap.
2065 * available in winmm.dll (thus known as the multimedia timers)
2066 * However apps can raise the system timer clock frequency using timeBeginPeriod()
2067 * increasing the accuracy up to 1 msec, at a cost in general system performance
2070 * One is based on high precision clocks:
2071 * - QueryPrecisionCounter (QPC)
2072 * This has much higher accuracy, but is not guaranteed monotonic, and
2073 * has lots of complications like clock jumps and different times on different
2074 * CPUs. It also has lower long term accuracy (i.e. it will drift compared to
2075 * the low precision clocks.
2077 * Additionally, the precision available in the timer-based wakeup such as
2078 * MsgWaitForMultipleObjectsEx (which is what the mainloop is based on) is based
2079 * on the TGT resolution, so by default it is ~15msec, but can be increased by apps.
2081 * The QPC timer has too many issues to be used as is. The only way it could be used
2082 * is to use it to interpolate the lower precision clocks. Firefox does something like
2084 * https://bugzilla.mozilla.org/show_bug.cgi?id=363258
2086 * However this seems quite complicated, so we're not doing this right now.
2088 * The approach we take instead is to use the TGT timer, extending it to 64bit
2089 * either by using the GTC64 value, or if that is not available, a process local
2090 * time epoch that we increment when we detect a timer wrap (assumes that we read
2091 * the time at least once every 50 days).
2094 * - We have a globally consistent monotonic clock on Vista and later
2095 * - We have a locally monotonic clock on XP
2096 * - Apps that need higher precision in timeouts and clock reads can call
2097 * timeBeginPeriod() to increase it as much as they want
2100 if (g_GetTickCount64 != NULL)
2102 guint32 ticks_as_32bit;
2104 ticks = g_GetTickCount64 ();
2105 ticks32 = timeGetTime();
2107 /* GTC64 and TGT are sampled at different times, however they
2108 * have the same base and source (msecs since system boot).
2109 * They can differ by as much as -16 to +16 msecs.
2110 * We can't just inject the low bits into the 64bit counter
2111 * as one of the counters can have wrapped in 32bit space and
2112 * the other not. Instead we calculate the signed difference
2113 * in 32bit space and apply that difference to the 64bit counter.
2115 ticks_as_32bit = (guint32)ticks;
2117 /* We could do some 2's complement hack, but we play it safe */
2118 if (ticks32 - ticks_as_32bit <= G_MAXINT32)
2119 ticks += ticks32 - ticks_as_32bit;
2121 ticks -= ticks_as_32bit - ticks32;
2127 epoch = g_atomic_int_get (&g_win32_tick_epoch);
2129 /* Must read ticks after the epoch. Then we're guaranteed
2130 * that the ticks value we read is higher or equal to any
2131 * previous ones that lead to the writing of the epoch.
2133 ticks32 = timeGetTime();
2135 /* We store the MSB of the current time as the LSB
2136 * of the epoch. Comparing these bits lets us detect when
2137 * the 32bit counter has wrapped so we can increase the
2140 * This will work as long as this function is called at
2141 * least once every ~24 days, which is half the wrap time
2142 * of a 32bit msec counter. I think this is pretty likely.
2144 * Note that g_win32_tick_epoch is a process local state,
2145 * so the monotonic clock will not be the same between
2148 if ((ticks32 >> 31) != (epoch & 1))
2151 g_atomic_int_set (&g_win32_tick_epoch, epoch);
2155 ticks = (guint64)ticks32 | ((guint64)epoch) << 31;
2158 return ticks * 1000;
2160 #else /* !HAVE_CLOCK_GETTIME && ! G_OS_WIN32*/
2164 g_get_current_time (&tv);
2166 return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec;
2171 g_main_dispatch_free (gpointer dispatch)
2173 g_slice_free (GMainDispatch, dispatch);
2176 /* Running the main loop */
2178 static GMainDispatch *
2181 static GPrivate depth_private = G_PRIVATE_INIT (g_main_dispatch_free);
2182 GMainDispatch *dispatch;
2184 dispatch = g_private_get (&depth_private);
2188 dispatch = g_slice_new0 (GMainDispatch);
2189 g_private_set (&depth_private, dispatch);
2198 * Returns the depth of the stack of calls to
2199 * g_main_context_dispatch() on any #GMainContext in the current thread.
2200 * That is, when called from the toplevel, it gives 0. When
2201 * called from within a callback from g_main_context_iteration()
2202 * (or g_main_loop_run(), etc.) it returns 1. When called from within
2203 * a callback to a recursive call to g_main_context_iteration(),
2204 * it returns 2. And so forth.
2206 * This function is useful in a situation like the following:
2207 * Imagine an extremely simple "garbage collected" system.
2210 * static GList *free_list;
2213 * allocate_memory (gsize size)
2215 * gpointer result = g_malloc (size);
2216 * free_list = g_list_prepend (free_list, result);
2221 * free_allocated_memory (void)
2224 * for (l = free_list; l; l = l->next);
2226 * g_list_free (free_list);
2234 * g_main_context_iteration (NULL, TRUE);
2235 * free_allocated_memory();
2239 * This works from an application, however, if you want to do the same
2240 * thing from a library, it gets more difficult, since you no longer
2241 * control the main loop. You might think you can simply use an idle
2242 * function to make the call to free_allocated_memory(), but that
2243 * doesn't work, since the idle function could be called from a
2244 * recursive callback. This can be fixed by using g_main_depth()
2248 * allocate_memory (gsize size)
2250 * FreeListBlock *block = g_new (FreeListBlock, 1);
2251 * block->mem = g_malloc (size);
2252 * block->depth = g_main_depth ();
2253 * free_list = g_list_prepend (free_list, block);
2254 * return block->mem;
2258 * free_allocated_memory (void)
2262 * int depth = g_main_depth ();
2263 * for (l = free_list; l; );
2265 * GList *next = l->next;
2266 * FreeListBlock *block = l->data;
2267 * if (block->depth > depth)
2269 * g_free (block->mem);
2271 * free_list = g_list_delete_link (free_list, l);
2279 * There is a temptation to use g_main_depth() to solve
2280 * problems with reentrancy. For instance, while waiting for data
2281 * to be received from the network in response to a menu item,
2282 * the menu item might be selected again. It might seem that
2283 * one could make the menu item's callback return immediately
2284 * and do nothing if g_main_depth() returns a value greater than 1.
2285 * However, this should be avoided since the user then sees selecting
2286 * the menu item do nothing. Furthermore, you'll find yourself adding
2287 * these checks all over your code, since there are doubtless many,
2288 * many things that the user could do. Instead, you can use the
2289 * following techniques:
2294 * Use gtk_widget_set_sensitive() or modal dialogs to prevent
2295 * the user from interacting with elements while the main
2296 * loop is recursing.
2301 * Avoid main loop recursion in situations where you can't handle
2302 * arbitrary callbacks. Instead, structure your code so that you
2303 * simply return to the main loop and then get called again when
2304 * there is more work to do.
2309 * Return value: The main loop recursion level in the current thread
2314 GMainDispatch *dispatch = get_dispatch ();
2315 return dispatch->depth;
2319 * g_main_current_source:
2321 * Returns the currently firing source for this thread.
2323 * Return value: (transfer none): The currently firing source or %NULL.
2328 g_main_current_source (void)
2330 GMainDispatch *dispatch = get_dispatch ();
2331 return dispatch->dispatching_sources ? dispatch->dispatching_sources->data : NULL;
2335 * g_source_is_destroyed:
2336 * @source: a #GSource
2338 * Returns whether @source has been destroyed.
2340 * This is important when you operate upon your objects
2341 * from within idle handlers, but may have freed the object
2342 * before the dispatch of your idle handler.
2346 * idle_callback (gpointer data)
2348 * SomeWidget *self = data;
2350 * GDK_THREADS_ENTER (<!-- -->);
2351 * /<!-- -->* do stuff with self *<!-- -->/
2352 * self->idle_id = 0;
2353 * GDK_THREADS_LEAVE (<!-- -->);
2355 * return G_SOURCE_REMOVE;
2359 * some_widget_do_stuff_later (SomeWidget *self)
2361 * self->idle_id = g_idle_add (idle_callback, self);
2365 * some_widget_finalize (GObject *object)
2367 * SomeWidget *self = SOME_WIDGET (object);
2369 * if (self->idle_id)
2370 * g_source_remove (self->idle_id);
2372 * G_OBJECT_CLASS (parent_class)->finalize (object);
2376 * This will fail in a multi-threaded application if the
2377 * widget is destroyed before the idle handler fires due
2378 * to the use after free in the callback. A solution, to
2379 * this particular problem, is to check to if the source
2380 * has already been destroy within the callback.
2384 * idle_callback (gpointer data)
2386 * SomeWidget *self = data;
2388 * GDK_THREADS_ENTER ();
2389 * if (!g_source_is_destroyed (g_main_current_source ()))
2391 * /<!-- -->* do stuff with self *<!-- -->/
2393 * GDK_THREADS_LEAVE ();
2399 * Return value: %TRUE if the source has been destroyed
2404 g_source_is_destroyed (GSource *source)
2406 return SOURCE_DESTROYED (source);
2409 /* Temporarily remove all this source's file descriptors from the
2410 * poll(), so that if data comes available for one of the file descriptors
2411 * we don't continually spin in the poll()
2413 /* HOLDS: source->context's lock */
2415 block_source (GSource *source)
2419 g_return_if_fail (!SOURCE_BLOCKED (source));
2421 source->flags |= G_SOURCE_BLOCKED;
2423 tmp_list = source->poll_fds;
2426 g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
2427 tmp_list = tmp_list->next;
2430 if (source->priv && source->priv->child_sources)
2432 tmp_list = source->priv->child_sources;
2435 block_source (tmp_list->data);
2436 tmp_list = tmp_list->next;
2441 /* HOLDS: source->context's lock */
2443 unblock_source (GSource *source)
2447 g_return_if_fail (SOURCE_BLOCKED (source)); /* Source already unblocked */
2448 g_return_if_fail (!SOURCE_DESTROYED (source));
2450 source->flags &= ~G_SOURCE_BLOCKED;
2452 tmp_list = source->poll_fds;
2455 g_main_context_add_poll_unlocked (source->context, source->priority, tmp_list->data);
2456 tmp_list = tmp_list->next;
2459 if (source->priv && source->priv->child_sources)
2461 tmp_list = source->priv->child_sources;
2464 unblock_source (tmp_list->data);
2465 tmp_list = tmp_list->next;
2470 /* HOLDS: context's lock */
2472 g_main_dispatch (GMainContext *context)
2474 GMainDispatch *current = get_dispatch ();
2477 for (i = 0; i < context->pending_dispatches->len; i++)
2479 GSource *source = context->pending_dispatches->pdata[i];
2481 context->pending_dispatches->pdata[i] = NULL;
2484 source->flags &= ~G_SOURCE_READY;
2486 if (!SOURCE_DESTROYED (source))
2488 gboolean was_in_call;
2489 gpointer user_data = NULL;
2490 GSourceFunc callback = NULL;
2491 GSourceCallbackFuncs *cb_funcs;
2493 gboolean need_destroy;
2495 gboolean (*dispatch) (GSource *,
2498 GSList current_source_link;
2500 dispatch = source->source_funcs->dispatch;
2501 cb_funcs = source->callback_funcs;
2502 cb_data = source->callback_data;
2505 cb_funcs->ref (cb_data);
2507 if ((source->flags & G_SOURCE_CAN_RECURSE) == 0)
2508 block_source (source);
2510 was_in_call = source->flags & G_HOOK_FLAG_IN_CALL;
2511 source->flags |= G_HOOK_FLAG_IN_CALL;
2514 cb_funcs->get (cb_data, source, &callback, &user_data);
2516 UNLOCK_CONTEXT (context);
2519 /* The on-stack allocation of the GSList is unconventional, but
2520 * we know that the lifetime of the link is bounded to this
2521 * function as the link is kept in a thread specific list and
2522 * not manipulated outside of this function and its descendants.
2523 * Avoiding the overhead of a g_slist_alloc() is useful as many
2524 * applications do little more than dispatch events.
2526 * This is a performance hack - do not revert to g_slist_prepend()!
2528 current_source_link.data = source;
2529 current_source_link.next = current->dispatching_sources;
2530 current->dispatching_sources = ¤t_source_link;
2531 need_destroy = ! dispatch (source,
2534 g_assert (current->dispatching_sources == ¤t_source_link);
2535 current->dispatching_sources = current_source_link.next;
2539 cb_funcs->unref (cb_data);
2541 LOCK_CONTEXT (context);
2544 source->flags &= ~G_HOOK_FLAG_IN_CALL;
2546 if (SOURCE_BLOCKED (source) && !SOURCE_DESTROYED (source))
2547 unblock_source (source);
2549 /* Note: this depends on the fact that we can't switch
2550 * sources from one main context to another
2552 if (need_destroy && !SOURCE_DESTROYED (source))
2554 g_assert (source->context == context);
2555 g_source_destroy_internal (source, context, TRUE);
2559 SOURCE_UNREF (source, context);
2562 g_ptr_array_set_size (context->pending_dispatches, 0);
2565 /* Holds context's lock */
2566 static inline GSource *
2567 next_valid_source (GMainContext *context,
2570 GSource *new_source = source ? source->next : context->source_list;
2574 if (!SOURCE_DESTROYED (new_source))
2576 new_source->ref_count++;
2580 new_source = new_source->next;
2584 SOURCE_UNREF (source, context);
2590 * g_main_context_acquire:
2591 * @context: a #GMainContext
2593 * Tries to become the owner of the specified context.
2594 * If some other thread is the owner of the context,
2595 * returns %FALSE immediately. Ownership is properly
2596 * recursive: the owner can require ownership again
2597 * and will release ownership when g_main_context_release()
2598 * is called as many times as g_main_context_acquire().
2600 * You must be the owner of a context before you
2601 * can call g_main_context_prepare(), g_main_context_query(),
2602 * g_main_context_check(), g_main_context_dispatch().
2604 * Return value: %TRUE if the operation succeeded, and
2605 * this thread is now the owner of @context.
2608 g_main_context_acquire (GMainContext *context)
2610 gboolean result = FALSE;
2611 GThread *self = G_THREAD_SELF;
2613 if (context == NULL)
2614 context = g_main_context_default ();
2616 LOCK_CONTEXT (context);
2618 if (!context->owner)
2620 context->owner = self;
2621 g_assert (context->owner_count == 0);
2624 if (context->owner == self)
2626 context->owner_count++;
2630 UNLOCK_CONTEXT (context);
2636 * g_main_context_release:
2637 * @context: a #GMainContext
2639 * Releases ownership of a context previously acquired by this thread
2640 * with g_main_context_acquire(). If the context was acquired multiple
2641 * times, the ownership will be released only when g_main_context_release()
2642 * is called as many times as it was acquired.
2645 g_main_context_release (GMainContext *context)
2647 if (context == NULL)
2648 context = g_main_context_default ();
2650 LOCK_CONTEXT (context);
2652 context->owner_count--;
2653 if (context->owner_count == 0)
2655 context->owner = NULL;
2657 if (context->waiters)
2659 GMainWaiter *waiter = context->waiters->data;
2660 gboolean loop_internal_waiter = (waiter->mutex == &context->mutex);
2661 context->waiters = g_slist_delete_link (context->waiters,
2663 if (!loop_internal_waiter)
2664 g_mutex_lock (waiter->mutex);
2666 g_cond_signal (waiter->cond);
2668 if (!loop_internal_waiter)
2669 g_mutex_unlock (waiter->mutex);
2673 UNLOCK_CONTEXT (context);
2677 * g_main_context_wait:
2678 * @context: a #GMainContext
2679 * @cond: a condition variable
2680 * @mutex: a mutex, currently held
2682 * Tries to become the owner of the specified context,
2683 * as with g_main_context_acquire(). But if another thread
2684 * is the owner, atomically drop @mutex and wait on @cond until
2685 * that owner releases ownership or until @cond is signaled, then
2686 * try again (once) to become the owner.
2688 * Return value: %TRUE if the operation succeeded, and
2689 * this thread is now the owner of @context.
2692 g_main_context_wait (GMainContext *context,
2696 gboolean result = FALSE;
2697 GThread *self = G_THREAD_SELF;
2698 gboolean loop_internal_waiter;
2700 if (context == NULL)
2701 context = g_main_context_default ();
2703 loop_internal_waiter = (mutex == &context->mutex);
2705 if (!loop_internal_waiter)
2706 LOCK_CONTEXT (context);
2708 if (context->owner && context->owner != self)
2713 waiter.mutex = mutex;
2715 context->waiters = g_slist_append (context->waiters, &waiter);
2717 if (!loop_internal_waiter)
2718 UNLOCK_CONTEXT (context);
2719 g_cond_wait (cond, mutex);
2720 if (!loop_internal_waiter)
2721 LOCK_CONTEXT (context);
2723 context->waiters = g_slist_remove (context->waiters, &waiter);
2726 if (!context->owner)
2728 context->owner = self;
2729 g_assert (context->owner_count == 0);
2732 if (context->owner == self)
2734 context->owner_count++;
2738 if (!loop_internal_waiter)
2739 UNLOCK_CONTEXT (context);
2745 * g_main_context_prepare:
2746 * @context: a #GMainContext
2747 * @priority: location to store priority of highest priority
2748 * source already ready.
2750 * Prepares to poll sources within a main loop. The resulting information
2751 * for polling is determined by calling g_main_context_query ().
2753 * Return value: %TRUE if some source is ready to be dispatched
2757 g_main_context_prepare (GMainContext *context,
2762 gint current_priority = G_MAXINT;
2765 if (context == NULL)
2766 context = g_main_context_default ();
2768 LOCK_CONTEXT (context);
2770 context->time_is_fresh = FALSE;
2772 if (context->in_check_or_prepare)
2774 g_warning ("g_main_context_prepare() called recursively from within a source's check() or "
2775 "prepare() member.");
2776 UNLOCK_CONTEXT (context);
2781 /* If recursing, finish up current dispatch, before starting over */
2782 if (context->pending_dispatches)
2785 g_main_dispatch (context, ¤t_time);
2787 UNLOCK_CONTEXT (context);
2792 /* If recursing, clear list of pending dispatches */
2794 for (i = 0; i < context->pending_dispatches->len; i++)
2796 if (context->pending_dispatches->pdata[i])
2797 SOURCE_UNREF ((GSource *)context->pending_dispatches->pdata[i], context);
2799 g_ptr_array_set_size (context->pending_dispatches, 0);
2801 /* Prepare all sources */
2803 context->timeout = -1;
2805 source = next_valid_source (context, NULL);
2808 gint source_timeout = -1;
2810 if ((n_ready > 0) && (source->priority > current_priority))
2812 SOURCE_UNREF (source, context);
2815 if (SOURCE_BLOCKED (source))
2818 if (!(source->flags & G_SOURCE_READY))
2821 gboolean (*prepare) (GSource *source,
2824 prepare = source->source_funcs->prepare;
2825 context->in_check_or_prepare++;
2826 UNLOCK_CONTEXT (context);
2828 result = (*prepare) (source, &source_timeout);
2830 LOCK_CONTEXT (context);
2831 context->in_check_or_prepare--;
2835 GSource *ready_source = source;
2837 while (ready_source)
2839 ready_source->flags |= G_SOURCE_READY;
2840 ready_source = ready_source->priv->parent_source;
2845 if (source->flags & G_SOURCE_READY)
2848 current_priority = source->priority;
2849 context->timeout = 0;
2852 if (source_timeout >= 0)
2854 if (context->timeout < 0)
2855 context->timeout = source_timeout;
2857 context->timeout = MIN (context->timeout, source_timeout);
2861 source = next_valid_source (context, source);
2864 UNLOCK_CONTEXT (context);
2867 *priority = current_priority;
2869 return (n_ready > 0);
2873 * g_main_context_query:
2874 * @context: a #GMainContext
2875 * @max_priority: maximum priority source to check
2876 * @timeout_: (out): location to store timeout to be used in polling
2877 * @fds: (out caller-allocates) (array length=n_fds): location to
2878 * store #GPollFD records that need to be polled.
2879 * @n_fds: length of @fds.
2881 * Determines information necessary to poll this main loop.
2883 * Return value: the number of records actually stored in @fds,
2884 * or, if more than @n_fds records need to be stored, the number
2885 * of records that need to be stored.
2888 g_main_context_query (GMainContext *context,
2897 LOCK_CONTEXT (context);
2899 pollrec = context->poll_records;
2901 while (pollrec && max_priority >= pollrec->priority)
2903 /* We need to include entries with fd->events == 0 in the array because
2904 * otherwise if the application changes fd->events behind our back and
2905 * makes it non-zero, we'll be out of sync when we check the fds[] array.
2906 * (Changing fd->events after adding an FD wasn't an anticipated use of
2907 * this API, but it occurs in practice.) */
2910 fds[n_poll].fd = pollrec->fd->fd;
2911 /* In direct contradiction to the Unix98 spec, IRIX runs into
2912 * difficulty if you pass in POLLERR, POLLHUP or POLLNVAL
2913 * flags in the events field of the pollfd while it should
2914 * just ignoring them. So we mask them out here.
2916 fds[n_poll].events = pollrec->fd->events & ~(G_IO_ERR|G_IO_HUP|G_IO_NVAL);
2917 fds[n_poll].revents = 0;
2920 pollrec = pollrec->next;
2924 context->poll_changed = FALSE;
2928 *timeout = context->timeout;
2930 context->time_is_fresh = FALSE;
2933 UNLOCK_CONTEXT (context);
2939 * g_main_context_check:
2940 * @context: a #GMainContext
2941 * @max_priority: the maximum numerical priority of sources to check
2942 * @fds: (array length=n_fds): array of #GPollFD's that was passed to
2943 * the last call to g_main_context_query()
2944 * @n_fds: return value of g_main_context_query()
2946 * Passes the results of polling back to the main loop.
2948 * Return value: %TRUE if some sources are ready to be dispatched.
2951 g_main_context_check (GMainContext *context,
2961 LOCK_CONTEXT (context);
2963 if (context->in_check_or_prepare)
2965 g_warning ("g_main_context_check() called recursively from within a source's check() or "
2966 "prepare() member.");
2967 UNLOCK_CONTEXT (context);
2971 if (context->wake_up_rec.revents)
2972 g_wakeup_acknowledge (context->wakeup);
2974 /* If the set of poll file descriptors changed, bail out
2975 * and let the main loop rerun
2977 if (context->poll_changed)
2979 UNLOCK_CONTEXT (context);
2983 pollrec = context->poll_records;
2987 if (pollrec->fd->events)
2988 pollrec->fd->revents = fds[i].revents;
2990 pollrec = pollrec->next;
2994 source = next_valid_source (context, NULL);
2997 if ((n_ready > 0) && (source->priority > max_priority))
2999 SOURCE_UNREF (source, context);
3002 if (SOURCE_BLOCKED (source))
3005 if (!(source->flags & G_SOURCE_READY))
3008 gboolean (*check) (GSource *source);
3010 check = source->source_funcs->check;
3012 context->in_check_or_prepare++;
3013 UNLOCK_CONTEXT (context);
3015 result = (*check) (source);
3017 LOCK_CONTEXT (context);
3018 context->in_check_or_prepare--;
3022 GSource *ready_source = source;
3024 while (ready_source)
3026 ready_source->flags |= G_SOURCE_READY;
3027 ready_source = ready_source->priv->parent_source;
3032 if (source->flags & G_SOURCE_READY)
3034 source->ref_count++;
3035 g_ptr_array_add (context->pending_dispatches, source);
3039 /* never dispatch sources with less priority than the first
3040 * one we choose to dispatch
3042 max_priority = source->priority;
3046 source = next_valid_source (context, source);
3049 UNLOCK_CONTEXT (context);
3055 * g_main_context_dispatch:
3056 * @context: a #GMainContext
3058 * Dispatches all pending sources.
3061 g_main_context_dispatch (GMainContext *context)
3063 LOCK_CONTEXT (context);
3065 if (context->pending_dispatches->len > 0)
3067 g_main_dispatch (context);
3070 UNLOCK_CONTEXT (context);
3073 /* HOLDS context lock */
3075 g_main_context_iterate (GMainContext *context,
3082 gboolean some_ready;
3083 gint nfds, allocated_nfds;
3084 GPollFD *fds = NULL;
3086 UNLOCK_CONTEXT (context);
3088 if (!g_main_context_acquire (context))
3090 gboolean got_ownership;
3092 LOCK_CONTEXT (context);
3097 got_ownership = g_main_context_wait (context,
3105 LOCK_CONTEXT (context);
3107 if (!context->cached_poll_array)
3109 context->cached_poll_array_size = context->n_poll_records;
3110 context->cached_poll_array = g_new (GPollFD, context->n_poll_records);
3113 allocated_nfds = context->cached_poll_array_size;
3114 fds = context->cached_poll_array;
3116 UNLOCK_CONTEXT (context);
3118 g_main_context_prepare (context, &max_priority);
3120 while ((nfds = g_main_context_query (context, max_priority, &timeout, fds,
3121 allocated_nfds)) > allocated_nfds)
3123 LOCK_CONTEXT (context);
3125 context->cached_poll_array_size = allocated_nfds = nfds;
3126 context->cached_poll_array = fds = g_new (GPollFD, nfds);
3127 UNLOCK_CONTEXT (context);
3133 g_main_context_poll (context, timeout, max_priority, fds, nfds);
3135 some_ready = g_main_context_check (context, max_priority, fds, nfds);
3138 g_main_context_dispatch (context);
3140 g_main_context_release (context);
3142 LOCK_CONTEXT (context);
3148 * g_main_context_pending:
3149 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
3151 * Checks if any sources have pending events for the given context.
3153 * Return value: %TRUE if events are pending.
3156 g_main_context_pending (GMainContext *context)
3161 context = g_main_context_default();
3163 LOCK_CONTEXT (context);
3164 retval = g_main_context_iterate (context, FALSE, FALSE, G_THREAD_SELF);
3165 UNLOCK_CONTEXT (context);
3171 * g_main_context_iteration:
3172 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
3173 * @may_block: whether the call may block.
3175 * Runs a single iteration for the given main loop. This involves
3176 * checking to see if any event sources are ready to be processed,
3177 * then if no events sources are ready and @may_block is %TRUE, waiting
3178 * for a source to become ready, then dispatching the highest priority
3179 * events sources that are ready. Otherwise, if @may_block is %FALSE
3180 * sources are not waited to become ready, only those highest priority
3181 * events sources will be dispatched (if any), that are ready at this
3182 * given moment without further waiting.
3184 * Note that even when @may_block is %TRUE, it is still possible for
3185 * g_main_context_iteration() to return %FALSE, since the the wait may
3186 * be interrupted for other reasons than an event source becoming ready.
3188 * Return value: %TRUE if events were dispatched.
3191 g_main_context_iteration (GMainContext *context, gboolean may_block)
3196 context = g_main_context_default();
3198 LOCK_CONTEXT (context);
3199 retval = g_main_context_iterate (context, may_block, TRUE, G_THREAD_SELF);
3200 UNLOCK_CONTEXT (context);
3207 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used).
3208 * @is_running: set to %TRUE to indicate that the loop is running. This
3209 * is not very important since calling g_main_loop_run() will set this to
3212 * Creates a new #GMainLoop structure.
3214 * Return value: a new #GMainLoop.
3217 g_main_loop_new (GMainContext *context,
3218 gboolean is_running)
3223 context = g_main_context_default();
3225 g_main_context_ref (context);
3227 loop = g_new0 (GMainLoop, 1);
3228 loop->context = context;
3229 loop->is_running = is_running != FALSE;
3230 loop->ref_count = 1;
3237 * @loop: a #GMainLoop
3239 * Increases the reference count on a #GMainLoop object by one.
3241 * Return value: @loop
3244 g_main_loop_ref (GMainLoop *loop)
3246 g_return_val_if_fail (loop != NULL, NULL);
3247 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
3249 g_atomic_int_inc (&loop->ref_count);
3255 * g_main_loop_unref:
3256 * @loop: a #GMainLoop
3258 * Decreases the reference count on a #GMainLoop object by one. If
3259 * the result is zero, free the loop and free all associated memory.
3262 g_main_loop_unref (GMainLoop *loop)
3264 g_return_if_fail (loop != NULL);
3265 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3267 if (!g_atomic_int_dec_and_test (&loop->ref_count))
3270 g_main_context_unref (loop->context);
3276 * @loop: a #GMainLoop
3278 * Runs a main loop until g_main_loop_quit() is called on the loop.
3279 * If this is called for the thread of the loop's #GMainContext,
3280 * it will process events from the loop, otherwise it will
3284 g_main_loop_run (GMainLoop *loop)
3286 GThread *self = G_THREAD_SELF;
3288 g_return_if_fail (loop != NULL);
3289 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3291 if (!g_main_context_acquire (loop->context))
3293 gboolean got_ownership = FALSE;
3295 /* Another thread owns this context */
3296 LOCK_CONTEXT (loop->context);
3298 g_atomic_int_inc (&loop->ref_count);
3300 if (!loop->is_running)
3301 loop->is_running = TRUE;
3303 while (loop->is_running && !got_ownership)
3304 got_ownership = g_main_context_wait (loop->context,
3305 &loop->context->cond,
3306 &loop->context->mutex);
3308 if (!loop->is_running)
3310 UNLOCK_CONTEXT (loop->context);
3312 g_main_context_release (loop->context);
3313 g_main_loop_unref (loop);
3317 g_assert (got_ownership);
3320 LOCK_CONTEXT (loop->context);
3322 if (loop->context->in_check_or_prepare)
3324 g_warning ("g_main_loop_run(): called recursively from within a source's "
3325 "check() or prepare() member, iteration not possible.");
3329 g_atomic_int_inc (&loop->ref_count);
3330 loop->is_running = TRUE;
3331 while (loop->is_running)
3332 g_main_context_iterate (loop->context, TRUE, TRUE, self);
3334 UNLOCK_CONTEXT (loop->context);
3336 g_main_context_release (loop->context);
3338 g_main_loop_unref (loop);
3343 * @loop: a #GMainLoop
3345 * Stops a #GMainLoop from running. Any calls to g_main_loop_run()
3346 * for the loop will return.
3348 * Note that sources that have already been dispatched when
3349 * g_main_loop_quit() is called will still be executed.
3352 g_main_loop_quit (GMainLoop *loop)
3354 g_return_if_fail (loop != NULL);
3355 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3357 LOCK_CONTEXT (loop->context);
3358 loop->is_running = FALSE;
3359 g_wakeup_signal (loop->context->wakeup);
3361 g_cond_broadcast (&loop->context->cond);
3363 UNLOCK_CONTEXT (loop->context);
3367 * g_main_loop_is_running:
3368 * @loop: a #GMainLoop.
3370 * Checks to see if the main loop is currently being run via g_main_loop_run().
3372 * Return value: %TRUE if the mainloop is currently being run.
3375 g_main_loop_is_running (GMainLoop *loop)
3377 g_return_val_if_fail (loop != NULL, FALSE);
3378 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, FALSE);
3380 return loop->is_running;
3384 * g_main_loop_get_context:
3385 * @loop: a #GMainLoop.
3387 * Returns the #GMainContext of @loop.
3389 * Return value: (transfer none): the #GMainContext of @loop
3392 g_main_loop_get_context (GMainLoop *loop)
3394 g_return_val_if_fail (loop != NULL, NULL);
3395 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
3397 return loop->context;
3400 /* HOLDS: context's lock */
3402 g_main_context_poll (GMainContext *context,
3408 #ifdef G_MAIN_POLL_DEBUG
3414 GPollFunc poll_func;
3416 if (n_fds || timeout != 0)
3418 #ifdef G_MAIN_POLL_DEBUG
3419 if (_g_main_poll_debug)
3421 g_print ("polling context=%p n=%d timeout=%d\n",
3422 context, n_fds, timeout);
3423 poll_timer = g_timer_new ();
3427 LOCK_CONTEXT (context);
3429 poll_func = context->poll_func;
3431 UNLOCK_CONTEXT (context);
3432 if ((*poll_func) (fds, n_fds, timeout) < 0 && errno != EINTR)
3435 g_warning ("poll(2) failed due to: %s.",
3436 g_strerror (errno));
3438 /* If g_poll () returns -1, it has already called g_warning() */
3442 #ifdef G_MAIN_POLL_DEBUG
3443 if (_g_main_poll_debug)
3445 LOCK_CONTEXT (context);
3447 g_print ("g_main_poll(%d) timeout: %d - elapsed %12.10f seconds",
3450 g_timer_elapsed (poll_timer, NULL));
3451 g_timer_destroy (poll_timer);
3452 pollrec = context->poll_records;
3454 while (pollrec != NULL)
3459 if (fds[i].fd == pollrec->fd->fd &&
3460 pollrec->fd->events &&
3463 g_print (" [" G_POLLFD_FORMAT " :", fds[i].fd);
3464 if (fds[i].revents & G_IO_IN)
3466 if (fds[i].revents & G_IO_OUT)
3468 if (fds[i].revents & G_IO_PRI)
3470 if (fds[i].revents & G_IO_ERR)
3472 if (fds[i].revents & G_IO_HUP)
3474 if (fds[i].revents & G_IO_NVAL)
3480 pollrec = pollrec->next;
3484 UNLOCK_CONTEXT (context);
3487 } /* if (n_fds || timeout != 0) */
3491 * g_main_context_add_poll:
3492 * @context: (allow-none): a #GMainContext (or %NULL for the default context)
3493 * @fd: a #GPollFD structure holding information about a file
3494 * descriptor to watch.
3495 * @priority: the priority for this file descriptor which should be
3496 * the same as the priority used for g_source_attach() to ensure that the
3497 * file descriptor is polled whenever the results may be needed.
3499 * Adds a file descriptor to the set of file descriptors polled for
3500 * this context. This will very seldom be used directly. Instead
3501 * a typical event source will use g_source_add_poll() instead.
3504 g_main_context_add_poll (GMainContext *context,
3509 context = g_main_context_default ();
3511 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3512 g_return_if_fail (fd);
3514 LOCK_CONTEXT (context);
3515 g_main_context_add_poll_unlocked (context, priority, fd);
3516 UNLOCK_CONTEXT (context);
3519 /* HOLDS: main_loop_lock */
3521 g_main_context_add_poll_unlocked (GMainContext *context,
3525 GPollRec *prevrec, *nextrec;
3526 GPollRec *newrec = g_slice_new (GPollRec);
3528 /* This file descriptor may be checked before we ever poll */
3531 newrec->priority = priority;
3533 prevrec = context->poll_records_tail;
3535 while (prevrec && priority < prevrec->priority)
3538 prevrec = prevrec->prev;
3542 prevrec->next = newrec;
3544 context->poll_records = newrec;
3546 newrec->prev = prevrec;
3547 newrec->next = nextrec;
3550 nextrec->prev = newrec;
3552 context->poll_records_tail = newrec;
3554 context->n_poll_records++;
3556 context->poll_changed = TRUE;
3558 /* Now wake up the main loop if it is waiting in the poll() */
3559 g_wakeup_signal (context->wakeup);
3563 * g_main_context_remove_poll:
3564 * @context:a #GMainContext
3565 * @fd: a #GPollFD descriptor previously added with g_main_context_add_poll()
3567 * Removes file descriptor from the set of file descriptors to be
3568 * polled for a particular context.
3571 g_main_context_remove_poll (GMainContext *context,
3575 context = g_main_context_default ();
3577 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3578 g_return_if_fail (fd);
3580 LOCK_CONTEXT (context);
3581 g_main_context_remove_poll_unlocked (context, fd);
3582 UNLOCK_CONTEXT (context);
3586 g_main_context_remove_poll_unlocked (GMainContext *context,
3589 GPollRec *pollrec, *prevrec, *nextrec;
3592 pollrec = context->poll_records;
3596 nextrec = pollrec->next;
3597 if (pollrec->fd == fd)
3599 if (prevrec != NULL)
3600 prevrec->next = nextrec;
3602 context->poll_records = nextrec;
3604 if (nextrec != NULL)
3605 nextrec->prev = prevrec;
3607 context->poll_records_tail = prevrec;
3609 g_slice_free (GPollRec, pollrec);
3611 context->n_poll_records--;
3618 context->poll_changed = TRUE;
3620 /* Now wake up the main loop if it is waiting in the poll() */
3621 g_wakeup_signal (context->wakeup);
3625 * g_source_get_current_time:
3626 * @source: a #GSource
3627 * @timeval: #GTimeVal structure in which to store current time.
3629 * This function ignores @source and is otherwise the same as
3630 * g_get_current_time().
3632 * Deprecated: 2.28: use g_source_get_time() instead
3635 g_source_get_current_time (GSource *source,
3638 g_get_current_time (timeval);
3642 * g_source_get_time:
3643 * @source: a #GSource
3645 * Gets the time to be used when checking this source. The advantage of
3646 * calling this function over calling g_get_monotonic_time() directly is
3647 * that when checking multiple sources, GLib can cache a single value
3648 * instead of having to repeatedly get the system monotonic time.
3650 * The time here is the system monotonic time, if available, or some
3651 * other reasonable alternative otherwise. See g_get_monotonic_time().
3653 * Returns: the monotonic time in microseconds
3658 g_source_get_time (GSource *source)
3660 GMainContext *context;
3663 g_return_val_if_fail (source->context != NULL, 0);
3665 context = source->context;
3667 LOCK_CONTEXT (context);
3669 if (!context->time_is_fresh)
3671 context->time = g_get_monotonic_time ();
3672 context->time_is_fresh = TRUE;
3675 result = context->time;
3677 UNLOCK_CONTEXT (context);
3683 * g_main_context_set_poll_func:
3684 * @context: a #GMainContext
3685 * @func: the function to call to poll all file descriptors
3687 * Sets the function to use to handle polling of file descriptors. It
3688 * will be used instead of the poll() system call
3689 * (or GLib's replacement function, which is used where
3690 * poll() isn't available).
3692 * This function could possibly be used to integrate the GLib event
3693 * loop with an external event loop.
3696 g_main_context_set_poll_func (GMainContext *context,
3700 context = g_main_context_default ();
3702 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3704 LOCK_CONTEXT (context);
3707 context->poll_func = func;
3709 context->poll_func = g_poll;
3711 UNLOCK_CONTEXT (context);
3715 * g_main_context_get_poll_func:
3716 * @context: a #GMainContext
3718 * Gets the poll function set by g_main_context_set_poll_func().
3720 * Return value: the poll function
3723 g_main_context_get_poll_func (GMainContext *context)
3728 context = g_main_context_default ();
3730 g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL);
3732 LOCK_CONTEXT (context);
3733 result = context->poll_func;
3734 UNLOCK_CONTEXT (context);
3740 * g_main_context_wakeup:
3741 * @context: a #GMainContext
3743 * If @context is currently waiting in a poll(), interrupt
3744 * the poll(), and continue the iteration process.
3747 g_main_context_wakeup (GMainContext *context)
3750 context = g_main_context_default ();
3752 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3754 g_wakeup_signal (context->wakeup);
3758 * g_main_context_is_owner:
3759 * @context: a #GMainContext
3761 * Determines whether this thread holds the (recursive)
3762 * ownership of this #GMainContext. This is useful to
3763 * know before waiting on another thread that may be
3764 * blocking to get ownership of @context.
3766 * Returns: %TRUE if current thread is owner of @context.
3771 g_main_context_is_owner (GMainContext *context)
3776 context = g_main_context_default ();
3778 LOCK_CONTEXT (context);
3779 is_owner = context->owner == G_THREAD_SELF;
3780 UNLOCK_CONTEXT (context);
3788 g_timeout_set_expiration (GTimeoutSource *timeout_source,
3789 gint64 current_time)
3791 timeout_source->expiration = current_time +
3792 (guint64) timeout_source->interval * 1000;
3794 if (timeout_source->seconds)
3797 static gint timer_perturb = -1;
3799 if (timer_perturb == -1)
3802 * we want a per machine/session unique 'random' value; try the dbus
3803 * address first, that has a UUID in it. If there is no dbus, use the
3804 * hostname for hashing.
3806 const char *session_bus_address = g_getenv ("DBUS_SESSION_BUS_ADDRESS");
3807 if (!session_bus_address)
3808 session_bus_address = g_getenv ("HOSTNAME");
3809 if (session_bus_address)
3810 timer_perturb = ABS ((gint) g_str_hash (session_bus_address)) % 1000000;
3815 /* We want the microseconds part of the timeout to land on the
3816 * 'timer_perturb' mark, but we need to make sure we don't try to
3817 * set the timeout in the past. We do this by ensuring that we
3818 * always only *increase* the expiration time by adding a full
3819 * second in the case that the microsecond portion decreases.
3821 timeout_source->expiration -= timer_perturb;
3823 remainder = timeout_source->expiration % 1000000;
3824 if (remainder >= 1000000/4)
3825 timeout_source->expiration += 1000000;
3827 timeout_source->expiration -= remainder;
3828 timeout_source->expiration += timer_perturb;
3833 g_timeout_prepare (GSource *source,
3836 GTimeoutSource *timeout_source = (GTimeoutSource *) source;
3837 gint64 now = g_source_get_time (source);
3839 if (now < timeout_source->expiration)
3841 /* Round up to ensure that we don't try again too early */
3842 *timeout = (timeout_source->expiration - now + 999) / 1000;
3851 g_timeout_check (GSource *source)
3853 GTimeoutSource *timeout_source = (GTimeoutSource *) source;
3854 gint64 now = g_source_get_time (source);
3856 return timeout_source->expiration <= now;
3860 g_timeout_dispatch (GSource *source,
3861 GSourceFunc callback,
3864 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3869 g_warning ("Timeout source dispatched without callback\n"
3870 "You must call g_source_set_callback().");
3874 again = callback (user_data);
3877 g_timeout_set_expiration (timeout_source, g_source_get_time (source));
3883 * g_timeout_source_new:
3884 * @interval: the timeout interval in milliseconds.
3886 * Creates a new timeout source.
3888 * The source will not initially be associated with any #GMainContext
3889 * and must be added to one with g_source_attach() before it will be
3892 * The interval given is in terms of monotonic time, not wall clock
3893 * time. See g_get_monotonic_time().
3895 * Return value: the newly-created timeout source
3898 g_timeout_source_new (guint interval)
3900 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
3901 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3903 timeout_source->interval = interval;
3904 g_timeout_set_expiration (timeout_source, g_get_monotonic_time ());
3910 * g_timeout_source_new_seconds:
3911 * @interval: the timeout interval in seconds
3913 * Creates a new timeout source.
3915 * The source will not initially be associated with any #GMainContext
3916 * and must be added to one with g_source_attach() before it will be
3919 * The scheduling granularity/accuracy of this timeout source will be
3922 * The interval given in terms of monotonic time, not wall clock time.
3923 * See g_get_monotonic_time().
3925 * Return value: the newly-created timeout source
3930 g_timeout_source_new_seconds (guint interval)
3932 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
3933 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3935 timeout_source->interval = 1000 * interval;
3936 timeout_source->seconds = TRUE;
3938 g_timeout_set_expiration (timeout_source, g_get_monotonic_time ());
3945 * g_timeout_add_full:
3946 * @priority: the priority of the timeout source. Typically this will be in
3947 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
3948 * @interval: the time between calls to the function, in milliseconds
3949 * (1/1000ths of a second)
3950 * @function: function to call
3951 * @data: data to pass to @function
3952 * @notify: (allow-none): function to call when the timeout is removed, or %NULL
3954 * Sets a function to be called at regular intervals, with the given
3955 * priority. The function is called repeatedly until it returns
3956 * %FALSE, at which point the timeout is automatically destroyed and
3957 * the function will not be called again. The @notify function is
3958 * called when the timeout is destroyed. The first call to the
3959 * function will be at the end of the first @interval.
3961 * Note that timeout functions may be delayed, due to the processing of other
3962 * event sources. Thus they should not be relied on for precise timing.
3963 * After each call to the timeout function, the time of the next
3964 * timeout is recalculated based on the current time and the given interval
3965 * (it does not try to 'catch up' time lost in delays).
3967 * This internally creates a main loop source using g_timeout_source_new()
3968 * and attaches it to the main loop context using g_source_attach(). You can
3969 * do these steps manually if you need greater control.
3971 * The interval given in terms of monotonic time, not wall clock time.
3972 * See g_get_monotonic_time().
3974 * Return value: the ID (greater than 0) of the event source.
3975 * Rename to: g_timeout_add
3978 g_timeout_add_full (gint priority,
3980 GSourceFunc function,
3982 GDestroyNotify notify)
3987 g_return_val_if_fail (function != NULL, 0);
3989 source = g_timeout_source_new (interval);
3991 if (priority != G_PRIORITY_DEFAULT)
3992 g_source_set_priority (source, priority);
3994 g_source_set_callback (source, function, data, notify);
3995 id = g_source_attach (source, NULL);
3996 g_source_unref (source);
4003 * @interval: the time between calls to the function, in milliseconds
4004 * (1/1000ths of a second)
4005 * @function: function to call
4006 * @data: data to pass to @function
4008 * Sets a function to be called at regular intervals, with the default
4009 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly
4010 * until it returns %FALSE, at which point the timeout is automatically
4011 * destroyed and the function will not be called again. The first call
4012 * to the function will be at the end of the first @interval.
4014 * Note that timeout functions may be delayed, due to the processing of other
4015 * event sources. Thus they should not be relied on for precise timing.
4016 * After each call to the timeout function, the time of the next
4017 * timeout is recalculated based on the current time and the given interval
4018 * (it does not try to 'catch up' time lost in delays).
4020 * If you want to have a timer in the "seconds" range and do not care
4021 * about the exact time of the first call of the timer, use the
4022 * g_timeout_add_seconds() function; this function allows for more
4023 * optimizations and more efficient system power usage.
4025 * This internally creates a main loop source using g_timeout_source_new()
4026 * and attaches it to the main loop context using g_source_attach(). You can
4027 * do these steps manually if you need greater control.
4029 * The interval given is in terms of monotonic time, not wall clock
4030 * time. See g_get_monotonic_time().
4032 * Return value: the ID (greater than 0) of the event source.
4035 g_timeout_add (guint32 interval,
4036 GSourceFunc function,
4039 return g_timeout_add_full (G_PRIORITY_DEFAULT,
4040 interval, function, data, NULL);
4044 * g_timeout_add_seconds_full:
4045 * @priority: the priority of the timeout source. Typically this will be in
4046 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
4047 * @interval: the time between calls to the function, in seconds
4048 * @function: function to call
4049 * @data: data to pass to @function
4050 * @notify: (allow-none): function to call when the timeout is removed, or %NULL
4052 * Sets a function to be called at regular intervals, with @priority.
4053 * The function is called repeatedly until it returns %FALSE, at which
4054 * point the timeout is automatically destroyed and the function will
4055 * not be called again.
4057 * Unlike g_timeout_add(), this function operates at whole second granularity.
4058 * The initial starting point of the timer is determined by the implementation
4059 * and the implementation is expected to group multiple timers together so that
4060 * they fire all at the same time.
4061 * To allow this grouping, the @interval to the first timer is rounded
4062 * and can deviate up to one second from the specified interval.
4063 * Subsequent timer iterations will generally run at the specified interval.
4065 * Note that timeout functions may be delayed, due to the processing of other
4066 * event sources. Thus they should not be relied on for precise timing.
4067 * After each call to the timeout function, the time of the next
4068 * timeout is recalculated based on the current time and the given @interval
4070 * If you want timing more precise than whole seconds, use g_timeout_add()
4073 * The grouping of timers to fire at the same time results in a more power
4074 * and CPU efficient behavior so if your timer is in multiples of seconds
4075 * and you don't require the first timer exactly one second from now, the
4076 * use of g_timeout_add_seconds() is preferred over g_timeout_add().
4078 * This internally creates a main loop source using
4079 * g_timeout_source_new_seconds() and attaches it to the main loop context
4080 * using g_source_attach(). You can do these steps manually if you need
4083 * The interval given is in terms of monotonic time, not wall clock
4084 * time. See g_get_monotonic_time().
4086 * Return value: the ID (greater than 0) of the event source.
4088 * Rename to: g_timeout_add_seconds
4092 g_timeout_add_seconds_full (gint priority,
4094 GSourceFunc function,
4096 GDestroyNotify notify)
4101 g_return_val_if_fail (function != NULL, 0);
4103 source = g_timeout_source_new_seconds (interval);
4105 if (priority != G_PRIORITY_DEFAULT)
4106 g_source_set_priority (source, priority);
4108 g_source_set_callback (source, function, data, notify);
4109 id = g_source_attach (source, NULL);
4110 g_source_unref (source);
4116 * g_timeout_add_seconds:
4117 * @interval: the time between calls to the function, in seconds
4118 * @function: function to call
4119 * @data: data to pass to @function
4121 * Sets a function to be called at regular intervals with the default
4122 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly until
4123 * it returns %FALSE, at which point the timeout is automatically destroyed
4124 * and the function will not be called again.
4126 * This internally creates a main loop source using
4127 * g_timeout_source_new_seconds() and attaches it to the main loop context
4128 * using g_source_attach(). You can do these steps manually if you need
4129 * greater control. Also see g_timeout_add_seconds_full().
4131 * Note that the first call of the timer may not be precise for timeouts
4132 * of one second. If you need finer precision and have such a timeout,
4133 * you may want to use g_timeout_add() instead.
4135 * The interval given is in terms of monotonic time, not wall clock
4136 * time. See g_get_monotonic_time().
4138 * Return value: the ID (greater than 0) of the event source.
4143 g_timeout_add_seconds (guint interval,
4144 GSourceFunc function,
4147 g_return_val_if_fail (function != NULL, 0);
4149 return g_timeout_add_seconds_full (G_PRIORITY_DEFAULT, interval, function, data, NULL);
4152 /* Child watch functions */
4157 g_child_watch_prepare (GSource *source,
4165 g_child_watch_check (GSource *source)
4167 GChildWatchSource *child_watch_source;
4168 gboolean child_exited;
4170 child_watch_source = (GChildWatchSource *) source;
4172 child_exited = child_watch_source->poll.revents & G_IO_IN;
4179 * Note: We do _not_ check for the special value of STILL_ACTIVE
4180 * since we know that the process has exited and doing so runs into
4181 * problems if the child process "happens to return STILL_ACTIVE(259)"
4182 * as Microsoft's Platform SDK puts it.
4184 if (!GetExitCodeProcess (child_watch_source->pid, &child_status))
4186 gchar *emsg = g_win32_error_message (GetLastError ());
4187 g_warning (G_STRLOC ": GetExitCodeProcess() failed: %s", emsg);
4190 child_watch_source->child_status = -1;
4193 child_watch_source->child_status = child_status;
4196 return child_exited;
4200 g_child_watch_finalize (GSource *source)
4204 #else /* G_OS_WIN32 */
4207 wake_source (GSource *source)
4209 GMainContext *context;
4211 /* This should be thread-safe:
4213 * - if the source is currently being added to a context, that
4214 * context will be woken up anyway
4216 * - if the source is currently being destroyed, we simply need not
4219 * - the memory for the source will remain valid until after the
4220 * source finalize function was called (which would remove the
4221 * source from the global list which we are currently holding the
4224 * - the GMainContext will either be NULL or point to a live
4227 * - the GMainContext will remain valid since we hold the
4228 * main_context_list lock
4230 * Since we are holding a lot of locks here, don't try to enter any
4231 * more GMainContext functions for fear of dealock -- just hit the
4232 * GWakeup and run. Even if that's safe now, it could easily become
4233 * unsafe with some very minor changes in the future, and signal
4234 * handling is not the most well-tested codepath.
4236 G_LOCK(main_context_list);
4237 context = source->context;
4239 g_wakeup_signal (context->wakeup);
4240 G_UNLOCK(main_context_list);
4244 dispatch_unix_signals (void)
4248 /* clear this first incase another one arrives while we're processing */
4249 any_unix_signal_pending = FALSE;
4251 G_LOCK(unix_signal_lock);
4253 /* handle GChildWatchSource instances */
4254 if (unix_signal_pending[SIGCHLD])
4256 unix_signal_pending[SIGCHLD] = FALSE;
4258 /* The only way we can do this is to scan all of the children.
4260 * The docs promise that we will not reap children that we are not
4261 * explicitly watching, so that ties our hands from calling
4262 * waitpid(-1). We also can't use siginfo's si_pid field since if
4263 * multiple SIGCHLD arrive at the same time, one of them can be
4264 * dropped (since a given UNIX signal can only be pending once).
4266 for (node = unix_child_watches; node; node = node->next)
4268 GChildWatchSource *source = node->data;
4270 if (!source->child_exited)
4272 if (waitpid (source->pid, &source->child_status, WNOHANG) > 0)
4274 source->child_exited = TRUE;
4276 wake_source ((GSource *) source);
4282 /* handle GUnixSignalWatchSource instances */
4283 for (node = unix_signal_watches; node; node = node->next)
4285 GUnixSignalWatchSource *source = node->data;
4287 if (!source->pending)
4289 if (unix_signal_pending[source->signum])
4291 unix_signal_pending[source->signum] = FALSE;
4292 source->pending = TRUE;
4294 wake_source ((GSource *) source);
4299 G_UNLOCK(unix_signal_lock);
4303 g_child_watch_prepare (GSource *source,
4306 GChildWatchSource *child_watch_source;
4308 child_watch_source = (GChildWatchSource *) source;
4310 return child_watch_source->child_exited;
4314 g_child_watch_check (GSource *source)
4316 GChildWatchSource *child_watch_source;
4318 child_watch_source = (GChildWatchSource *) source;
4320 return child_watch_source->child_exited;
4324 g_unix_signal_watch_prepare (GSource *source,
4327 GUnixSignalWatchSource *unix_signal_source;
4329 unix_signal_source = (GUnixSignalWatchSource *) source;
4331 return unix_signal_source->pending;
4335 g_unix_signal_watch_check (GSource *source)
4337 GUnixSignalWatchSource *unix_signal_source;
4339 unix_signal_source = (GUnixSignalWatchSource *) source;
4341 return unix_signal_source->pending;
4345 g_unix_signal_watch_dispatch (GSource *source,
4346 GSourceFunc callback,
4349 GUnixSignalWatchSource *unix_signal_source;
4351 unix_signal_source = (GUnixSignalWatchSource *) source;
4355 g_warning ("Unix signal source dispatched without callback\n"
4356 "You must call g_source_set_callback().");
4360 (callback) (user_data);
4362 unix_signal_source->pending = FALSE;
4368 ensure_unix_signal_handler_installed_unlocked (int signum)
4370 static sigset_t installed_signal_mask;
4371 static gboolean initialized;
4372 struct sigaction action;
4376 sigemptyset (&installed_signal_mask);
4377 g_get_worker_context ();
4381 if (sigismember (&installed_signal_mask, signum))
4384 sigaddset (&installed_signal_mask, signum);
4386 action.sa_handler = g_unix_signal_handler;
4387 sigemptyset (&action.sa_mask);
4388 action.sa_flags = SA_RESTART | SA_NOCLDSTOP;
4389 sigaction (signum, &action, NULL);
4393 _g_main_create_unix_signal_watch (int signum)
4396 GUnixSignalWatchSource *unix_signal_source;
4398 source = g_source_new (&g_unix_signal_funcs, sizeof (GUnixSignalWatchSource));
4399 unix_signal_source = (GUnixSignalWatchSource *) source;
4401 unix_signal_source->signum = signum;
4402 unix_signal_source->pending = FALSE;
4404 G_LOCK (unix_signal_lock);
4405 ensure_unix_signal_handler_installed_unlocked (signum);
4406 unix_signal_watches = g_slist_prepend (unix_signal_watches, unix_signal_source);
4407 if (unix_signal_pending[signum])
4408 unix_signal_source->pending = TRUE;
4409 unix_signal_pending[signum] = FALSE;
4410 G_UNLOCK (unix_signal_lock);
4416 g_unix_signal_watch_finalize (GSource *source)
4418 G_LOCK (unix_signal_lock);
4419 unix_signal_watches = g_slist_remove (unix_signal_watches, source);
4420 G_UNLOCK (unix_signal_lock);
4424 g_child_watch_finalize (GSource *source)
4426 G_LOCK (unix_signal_lock);
4427 unix_child_watches = g_slist_remove (unix_child_watches, source);
4428 G_UNLOCK (unix_signal_lock);
4431 #endif /* G_OS_WIN32 */
4434 g_child_watch_dispatch (GSource *source,
4435 GSourceFunc callback,
4438 GChildWatchSource *child_watch_source;
4439 GChildWatchFunc child_watch_callback = (GChildWatchFunc) callback;
4441 child_watch_source = (GChildWatchSource *) source;
4445 g_warning ("Child watch source dispatched without callback\n"
4446 "You must call g_source_set_callback().");
4450 (child_watch_callback) (child_watch_source->pid, child_watch_source->child_status, user_data);
4452 /* We never keep a child watch source around as the child is gone */
4459 g_unix_signal_handler (int signum)
4461 unix_signal_pending[signum] = TRUE;
4462 any_unix_signal_pending = TRUE;
4464 g_wakeup_signal (glib_worker_context->wakeup);
4467 #endif /* !G_OS_WIN32 */
4470 * g_child_watch_source_new:
4471 * @pid: process to watch. On POSIX the pid of a child process. On
4472 * Windows a handle for a process (which doesn't have to be a child).
4474 * Creates a new child_watch source.
4476 * The source will not initially be associated with any #GMainContext
4477 * and must be added to one with g_source_attach() before it will be
4480 * Note that child watch sources can only be used in conjunction with
4481 * <literal>g_spawn...</literal> when the %G_SPAWN_DO_NOT_REAP_CHILD
4484 * Note that on platforms where #GPid must be explicitly closed
4485 * (see g_spawn_close_pid()) @pid must not be closed while the
4486 * source is still active. Typically, you will want to call
4487 * g_spawn_close_pid() in the callback function for the source.
4489 * Note further that using g_child_watch_source_new() is not
4490 * compatible with calling <literal>waitpid(-1)</literal> in
4491 * the application. Calling waitpid() for individual pids will
4494 * Return value: the newly-created child watch source
4499 g_child_watch_source_new (GPid pid)
4501 GSource *source = g_source_new (&g_child_watch_funcs, sizeof (GChildWatchSource));
4502 GChildWatchSource *child_watch_source = (GChildWatchSource *)source;
4504 child_watch_source->pid = pid;
4507 child_watch_source->poll.fd = (gintptr) pid;
4508 child_watch_source->poll.events = G_IO_IN;
4510 g_source_add_poll (source, &child_watch_source->poll);
4511 #else /* G_OS_WIN32 */
4512 G_LOCK (unix_signal_lock);
4513 ensure_unix_signal_handler_installed_unlocked (SIGCHLD);
4514 unix_child_watches = g_slist_prepend (unix_child_watches, child_watch_source);
4515 if (waitpid (pid, &child_watch_source->child_status, WNOHANG) > 0)
4516 child_watch_source->child_exited = TRUE;
4517 G_UNLOCK (unix_signal_lock);
4518 #endif /* G_OS_WIN32 */
4524 * g_child_watch_add_full:
4525 * @priority: the priority of the idle source. Typically this will be in the
4526 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
4527 * @pid: process to watch. On POSIX the pid of a child process. On
4528 * Windows a handle for a process (which doesn't have to be a child).
4529 * @function: function to call
4530 * @data: data to pass to @function
4531 * @notify: (allow-none): function to call when the idle is removed, or %NULL
4533 * Sets a function to be called when the child indicated by @pid
4534 * exits, at the priority @priority.
4536 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
4537 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
4538 * the spawn function for the child watching to work.
4540 * Note that on platforms where #GPid must be explicitly closed
4541 * (see g_spawn_close_pid()) @pid must not be closed while the
4542 * source is still active. Typically, you will want to call
4543 * g_spawn_close_pid() in the callback function for the source.
4545 * GLib supports only a single callback per process id.
4547 * This internally creates a main loop source using
4548 * g_child_watch_source_new() and attaches it to the main loop context
4549 * using g_source_attach(). You can do these steps manually if you
4550 * need greater control.
4552 * Return value: the ID (greater than 0) of the event source.
4554 * Rename to: g_child_watch_add
4558 g_child_watch_add_full (gint priority,
4560 GChildWatchFunc function,
4562 GDestroyNotify notify)
4567 g_return_val_if_fail (function != NULL, 0);
4569 source = g_child_watch_source_new (pid);
4571 if (priority != G_PRIORITY_DEFAULT)
4572 g_source_set_priority (source, priority);
4574 g_source_set_callback (source, (GSourceFunc) function, data, notify);
4575 id = g_source_attach (source, NULL);
4576 g_source_unref (source);
4582 * g_child_watch_add:
4583 * @pid: process id to watch. On POSIX the pid of a child process. On
4584 * Windows a handle for a process (which doesn't have to be a child).
4585 * @function: function to call
4586 * @data: data to pass to @function
4588 * Sets a function to be called when the child indicated by @pid
4589 * exits, at a default priority, #G_PRIORITY_DEFAULT.
4591 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
4592 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
4593 * the spawn function for the child watching to work.
4595 * Note that on platforms where #GPid must be explicitly closed
4596 * (see g_spawn_close_pid()) @pid must not be closed while the
4597 * source is still active. Typically, you will want to call
4598 * g_spawn_close_pid() in the callback function for the source.
4600 * GLib supports only a single callback per process id.
4602 * This internally creates a main loop source using
4603 * g_child_watch_source_new() and attaches it to the main loop context
4604 * using g_source_attach(). You can do these steps manually if you
4605 * need greater control.
4607 * Return value: the ID (greater than 0) of the event source.
4612 g_child_watch_add (GPid pid,
4613 GChildWatchFunc function,
4616 return g_child_watch_add_full (G_PRIORITY_DEFAULT, pid, function, data, NULL);
4620 /* Idle functions */
4623 g_idle_prepare (GSource *source,
4632 g_idle_check (GSource *source)
4638 g_idle_dispatch (GSource *source,
4639 GSourceFunc callback,
4644 g_warning ("Idle source dispatched without callback\n"
4645 "You must call g_source_set_callback().");
4649 return callback (user_data);
4653 * g_idle_source_new:
4655 * Creates a new idle source.
4657 * The source will not initially be associated with any #GMainContext
4658 * and must be added to one with g_source_attach() before it will be
4659 * executed. Note that the default priority for idle sources is
4660 * %G_PRIORITY_DEFAULT_IDLE, as compared to other sources which
4661 * have a default priority of %G_PRIORITY_DEFAULT.
4663 * Return value: the newly-created idle source
4666 g_idle_source_new (void)
4670 source = g_source_new (&g_idle_funcs, sizeof (GSource));
4671 g_source_set_priority (source, G_PRIORITY_DEFAULT_IDLE);
4678 * @priority: the priority of the idle source. Typically this will be in the
4679 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
4680 * @function: function to call
4681 * @data: data to pass to @function
4682 * @notify: (allow-none): function to call when the idle is removed, or %NULL
4684 * Adds a function to be called whenever there are no higher priority
4685 * events pending. If the function returns %FALSE it is automatically
4686 * removed from the list of event sources and will not be called again.
4688 * This internally creates a main loop source using g_idle_source_new()
4689 * and attaches it to the main loop context using g_source_attach().
4690 * You can do these steps manually if you need greater control.
4692 * Return value: the ID (greater than 0) of the event source.
4693 * Rename to: g_idle_add
4696 g_idle_add_full (gint priority,
4697 GSourceFunc function,
4699 GDestroyNotify notify)
4704 g_return_val_if_fail (function != NULL, 0);
4706 source = g_idle_source_new ();
4708 if (priority != G_PRIORITY_DEFAULT_IDLE)
4709 g_source_set_priority (source, priority);
4711 g_source_set_callback (source, function, data, notify);
4712 id = g_source_attach (source, NULL);
4713 g_source_unref (source);
4720 * @function: function to call
4721 * @data: data to pass to @function.
4723 * Adds a function to be called whenever there are no higher priority
4724 * events pending to the default main loop. The function is given the
4725 * default idle priority, #G_PRIORITY_DEFAULT_IDLE. If the function
4726 * returns %FALSE it is automatically removed from the list of event
4727 * sources and will not be called again.
4729 * This internally creates a main loop source using g_idle_source_new()
4730 * and attaches it to the main loop context using g_source_attach().
4731 * You can do these steps manually if you need greater control.
4733 * Return value: the ID (greater than 0) of the event source.
4736 g_idle_add (GSourceFunc function,
4739 return g_idle_add_full (G_PRIORITY_DEFAULT_IDLE, function, data, NULL);
4743 * g_idle_remove_by_data:
4744 * @data: the data for the idle source's callback.
4746 * Removes the idle function with the given data.
4748 * Return value: %TRUE if an idle source was found and removed.
4751 g_idle_remove_by_data (gpointer data)
4753 return g_source_remove_by_funcs_user_data (&g_idle_funcs, data);
4757 * g_main_context_invoke:
4758 * @context: (allow-none): a #GMainContext, or %NULL
4759 * @function: function to call
4760 * @data: data to pass to @function
4762 * Invokes a function in such a way that @context is owned during the
4763 * invocation of @function.
4765 * If @context is %NULL then the global default main context — as
4766 * returned by g_main_context_default() — is used.
4768 * If @context is owned by the current thread, @function is called
4769 * directly. Otherwise, if @context is the thread-default main context
4770 * of the current thread and g_main_context_acquire() succeeds, then
4771 * @function is called and g_main_context_release() is called
4774 * In any other case, an idle source is created to call @function and
4775 * that source is attached to @context (presumably to be run in another
4776 * thread). The idle source is attached with #G_PRIORITY_DEFAULT
4777 * priority. If you want a different priority, use
4778 * g_main_context_invoke_full().
4780 * Note that, as with normal idle functions, @function should probably
4781 * return %FALSE. If it returns %TRUE, it will be continuously run in a
4782 * loop (and may prevent this call from returning).
4787 g_main_context_invoke (GMainContext *context,
4788 GSourceFunc function,
4791 g_main_context_invoke_full (context,
4793 function, data, NULL);
4797 * g_main_context_invoke_full:
4798 * @context: (allow-none): a #GMainContext, or %NULL
4799 * @priority: the priority at which to run @function
4800 * @function: function to call
4801 * @data: data to pass to @function
4802 * @notify: (allow-none): a function to call when @data is no longer in use, or %NULL.
4804 * Invokes a function in such a way that @context is owned during the
4805 * invocation of @function.
4807 * This function is the same as g_main_context_invoke() except that it
4808 * lets you specify the priority incase @function ends up being
4809 * scheduled as an idle and also lets you give a #GDestroyNotify for @data.
4811 * @notify should not assume that it is called from any particular
4812 * thread or with any particular context acquired.
4817 g_main_context_invoke_full (GMainContext *context,
4819 GSourceFunc function,
4821 GDestroyNotify notify)
4823 g_return_if_fail (function != NULL);
4826 context = g_main_context_default ();
4828 if (g_main_context_is_owner (context))
4830 while (function (data));
4837 GMainContext *thread_default;
4839 thread_default = g_main_context_get_thread_default ();
4841 if (!thread_default)
4842 thread_default = g_main_context_default ();
4844 if (thread_default == context && g_main_context_acquire (context))
4846 while (function (data));
4848 g_main_context_release (context);
4857 source = g_idle_source_new ();
4858 g_source_set_priority (source, priority);
4859 g_source_set_callback (source, function, data, notify);
4860 g_source_attach (source, context);
4861 g_source_unref (source);
4867 glib_worker_main (gpointer data)
4871 g_main_context_iteration (glib_worker_context, TRUE);
4874 if (any_unix_signal_pending)
4875 dispatch_unix_signals ();
4879 return NULL; /* worst GCC warning message ever... */
4883 g_get_worker_context (void)
4885 static gsize initialised;
4887 if (g_once_init_enter (&initialised))
4889 /* mask all signals in the worker thread */
4895 pthread_sigmask (SIG_SETMASK, &all, &prev_mask);
4897 glib_worker_context = g_main_context_new ();
4898 g_thread_new ("gmain", glib_worker_main, NULL);
4900 pthread_sigmask (SIG_SETMASK, &prev_mask, NULL);
4902 g_once_init_leave (&initialised, TRUE);
4905 return glib_worker_context;