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)
197 typedef struct _GMainWaiter GMainWaiter;
205 typedef struct _GMainDispatch GMainDispatch;
207 struct _GMainDispatch
210 GSList *dispatching_sources; /* stack of current sources */
213 #ifdef G_MAIN_POLL_DEBUG
214 gboolean _g_main_poll_debug = FALSE;
219 /* The following lock is used for both the list of sources
220 * and the list of poll records
230 GPtrArray *pending_dispatches;
231 gint timeout; /* Timeout for current iteration */
234 GSource *source_list;
235 gint in_check_or_prepare;
237 GPollRec *poll_records, *poll_records_tail;
238 guint n_poll_records;
239 GPollFD *cached_poll_array;
240 guint cached_poll_array_size;
246 /* Flag indicating whether the set of fd's changed during a poll */
247 gboolean poll_changed;
252 gboolean time_is_fresh;
255 struct _GSourceCallback
260 GDestroyNotify notify;
265 GMainContext *context;
270 struct _GTimeoutSource
278 struct _GChildWatchSource
285 #else /* G_OS_WIN32 */
286 gboolean child_exited;
287 #endif /* G_OS_WIN32 */
290 struct _GUnixSignalWatchSource
305 struct _GSourcePrivate
307 GSList *child_sources;
308 GSource *parent_source;
311 #define LOCK_CONTEXT(context) g_mutex_lock (&context->mutex)
312 #define UNLOCK_CONTEXT(context) g_mutex_unlock (&context->mutex)
313 #define G_THREAD_SELF g_thread_self ()
315 #define SOURCE_DESTROYED(source) (((source)->flags & G_HOOK_FLAG_ACTIVE) == 0)
316 #define SOURCE_BLOCKED(source) (((source)->flags & G_HOOK_FLAG_IN_CALL) != 0 && \
317 ((source)->flags & G_SOURCE_CAN_RECURSE) == 0)
319 #define SOURCE_UNREF(source, context) \
321 if ((source)->ref_count > 1) \
322 (source)->ref_count--; \
324 g_source_unref_internal ((source), (context), TRUE); \
328 /* Forward declarations */
330 static void g_source_unref_internal (GSource *source,
331 GMainContext *context,
333 static void g_source_destroy_internal (GSource *source,
334 GMainContext *context,
336 static void g_source_set_priority_unlocked (GSource *source,
337 GMainContext *context,
339 static void g_main_context_poll (GMainContext *context,
344 static void g_main_context_add_poll_unlocked (GMainContext *context,
347 static void g_main_context_remove_poll_unlocked (GMainContext *context,
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: 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: 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);
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 *tmp_source, *last_source;
815 if (source->priv && source->priv->parent_source)
817 /* Put the source immediately before its parent */
818 tmp_source = source->priv->parent_source;
819 last_source = source->priv->parent_source->prev;
824 tmp_source = context->source_list;
825 while (tmp_source && tmp_source->priority <= source->priority)
827 last_source = tmp_source;
828 tmp_source = tmp_source->next;
832 source->next = tmp_source;
834 tmp_source->prev = source;
836 source->prev = last_source;
838 last_source->next = source;
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;
883 tmp_list = source->priv->child_sources;
886 g_source_attach_unlocked (tmp_list->data, context);
887 tmp_list = tmp_list->next;
896 * @source: a #GSource
897 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
899 * Adds a #GSource to a @context so that it will be executed within
900 * that context. Remove it by calling g_source_destroy().
902 * Return value: the ID (greater than 0) for the source within the
906 g_source_attach (GSource *source,
907 GMainContext *context)
911 g_return_val_if_fail (source->context == NULL, 0);
912 g_return_val_if_fail (!SOURCE_DESTROYED (source), 0);
915 context = g_main_context_default ();
917 LOCK_CONTEXT (context);
919 result = g_source_attach_unlocked (source, context);
921 /* If another thread has acquired the context, wake it up since it
922 * might be in poll() right now.
924 if (context->owner && context->owner != G_THREAD_SELF)
925 g_wakeup_signal (context->wakeup);
927 UNLOCK_CONTEXT (context);
933 g_source_destroy_internal (GSource *source,
934 GMainContext *context,
938 LOCK_CONTEXT (context);
940 if (!SOURCE_DESTROYED (source))
943 gpointer old_cb_data;
944 GSourceCallbackFuncs *old_cb_funcs;
946 source->flags &= ~G_HOOK_FLAG_ACTIVE;
948 old_cb_data = source->callback_data;
949 old_cb_funcs = source->callback_funcs;
951 source->callback_data = NULL;
952 source->callback_funcs = NULL;
956 UNLOCK_CONTEXT (context);
957 old_cb_funcs->unref (old_cb_data);
958 LOCK_CONTEXT (context);
961 if (!SOURCE_BLOCKED (source))
963 tmp_list = source->poll_fds;
966 g_main_context_remove_poll_unlocked (context, tmp_list->data);
967 tmp_list = tmp_list->next;
971 if (source->priv && source->priv->child_sources)
973 /* This is safe because even if a child_source finalizer or
974 * closure notify tried to modify source->priv->child_sources
975 * from outside the lock, it would fail since
976 * SOURCE_DESTROYED(source) is now TRUE.
978 tmp_list = source->priv->child_sources;
981 g_source_destroy_internal (tmp_list->data, context, TRUE);
982 g_source_unref_internal (tmp_list->data, context, TRUE);
983 tmp_list = tmp_list->next;
985 g_slist_free (source->priv->child_sources);
986 source->priv->child_sources = NULL;
989 g_source_unref_internal (source, context, TRUE);
993 UNLOCK_CONTEXT (context);
998 * @source: a #GSource
1000 * Removes a source from its #GMainContext, if any, and mark it as
1001 * destroyed. The source cannot be subsequently added to another
1005 g_source_destroy (GSource *source)
1007 GMainContext *context;
1009 g_return_if_fail (source != NULL);
1011 context = source->context;
1014 g_source_destroy_internal (source, context, FALSE);
1016 source->flags &= ~G_HOOK_FLAG_ACTIVE;
1021 * @source: a #GSource
1023 * Returns the numeric ID for a particular source. The ID of a source
1024 * is a positive integer which is unique within a particular main loop
1025 * context. The reverse
1026 * mapping from ID to source is done by g_main_context_find_source_by_id().
1028 * Return value: the ID (greater than 0) for the source
1031 g_source_get_id (GSource *source)
1035 g_return_val_if_fail (source != NULL, 0);
1036 g_return_val_if_fail (source->context != NULL, 0);
1038 LOCK_CONTEXT (source->context);
1039 result = source->source_id;
1040 UNLOCK_CONTEXT (source->context);
1046 * g_source_get_context:
1047 * @source: a #GSource
1049 * Gets the #GMainContext with which the source is associated.
1050 * Calling this function on a destroyed source is an error.
1052 * Return value: (transfer none): the #GMainContext with which the
1053 * source is associated, or %NULL if the context has not
1054 * yet been added to a source.
1057 g_source_get_context (GSource *source)
1059 g_return_val_if_fail (!SOURCE_DESTROYED (source), NULL);
1061 return source->context;
1065 * g_source_add_poll:
1066 * @source:a #GSource
1067 * @fd: a #GPollFD structure holding information about a file
1068 * descriptor to watch.
1070 * Adds a file descriptor to the set of file descriptors polled for
1071 * this source. This is usually combined with g_source_new() to add an
1072 * event source. The event source's check function will typically test
1073 * the @revents field in the #GPollFD struct and return %TRUE if events need
1077 g_source_add_poll (GSource *source,
1080 GMainContext *context;
1082 g_return_if_fail (source != NULL);
1083 g_return_if_fail (fd != NULL);
1084 g_return_if_fail (!SOURCE_DESTROYED (source));
1086 context = source->context;
1089 LOCK_CONTEXT (context);
1091 source->poll_fds = g_slist_prepend (source->poll_fds, fd);
1095 if (!SOURCE_BLOCKED (source))
1096 g_main_context_add_poll_unlocked (context, source->priority, fd);
1097 UNLOCK_CONTEXT (context);
1102 * g_source_remove_poll:
1103 * @source:a #GSource
1104 * @fd: a #GPollFD structure previously passed to g_source_add_poll().
1106 * Removes a file descriptor from the set of file descriptors polled for
1110 g_source_remove_poll (GSource *source,
1113 GMainContext *context;
1115 g_return_if_fail (source != NULL);
1116 g_return_if_fail (fd != NULL);
1117 g_return_if_fail (!SOURCE_DESTROYED (source));
1119 context = source->context;
1122 LOCK_CONTEXT (context);
1124 source->poll_fds = g_slist_remove (source->poll_fds, fd);
1128 if (!SOURCE_BLOCKED (source))
1129 g_main_context_remove_poll_unlocked (context, fd);
1130 UNLOCK_CONTEXT (context);
1135 * g_source_add_child_source:
1136 * @source:a #GSource
1137 * @child_source: a second #GSource that @source should "poll"
1139 * Adds @child_source to @source as a "polled" source; when @source is
1140 * added to a #GMainContext, @child_source will be automatically added
1141 * with the same priority, when @child_source is triggered, it will
1142 * cause @source to dispatch (in addition to calling its own
1143 * callback), and when @source is destroyed, it will destroy
1144 * @child_source as well. (@source will also still be dispatched if
1145 * its own prepare/check functions indicate that it is ready.)
1147 * If you don't need @child_source to do anything on its own when it
1148 * triggers, you can call g_source_set_dummy_callback() on it to set a
1149 * callback that does nothing (except return %TRUE if appropriate).
1151 * @source will hold a reference on @child_source while @child_source
1152 * is attached to it.
1157 g_source_add_child_source (GSource *source,
1158 GSource *child_source)
1160 GMainContext *context;
1162 g_return_if_fail (source != NULL);
1163 g_return_if_fail (child_source != NULL);
1164 g_return_if_fail (!SOURCE_DESTROYED (source));
1165 g_return_if_fail (!SOURCE_DESTROYED (child_source));
1166 g_return_if_fail (child_source->context == NULL);
1167 g_return_if_fail (child_source->priv == NULL || child_source->priv->parent_source == NULL);
1169 context = source->context;
1172 LOCK_CONTEXT (context);
1175 source->priv = g_slice_new0 (GSourcePrivate);
1176 if (!child_source->priv)
1177 child_source->priv = g_slice_new0 (GSourcePrivate);
1179 source->priv->child_sources = g_slist_prepend (source->priv->child_sources,
1180 g_source_ref (child_source));
1181 child_source->priv->parent_source = source;
1182 g_source_set_priority_unlocked (child_source, NULL, source->priority);
1186 UNLOCK_CONTEXT (context);
1187 g_source_attach (child_source, context);
1192 * g_source_remove_child_source:
1193 * @source:a #GSource
1194 * @child_source: a #GSource previously passed to
1195 * g_source_add_child_source().
1197 * Detaches @child_source from @source and destroys it.
1202 g_source_remove_child_source (GSource *source,
1203 GSource *child_source)
1205 GMainContext *context;
1207 g_return_if_fail (source != NULL);
1208 g_return_if_fail (child_source != NULL);
1209 g_return_if_fail (child_source->priv != NULL && child_source->priv->parent_source == source);
1210 g_return_if_fail (!SOURCE_DESTROYED (source));
1211 g_return_if_fail (!SOURCE_DESTROYED (child_source));
1213 context = source->context;
1216 LOCK_CONTEXT (context);
1218 source->priv->child_sources = g_slist_remove (source->priv->child_sources, child_source);
1219 g_source_destroy_internal (child_source, context, TRUE);
1220 g_source_unref_internal (child_source, context, TRUE);
1223 UNLOCK_CONTEXT (context);
1227 * g_source_set_callback_indirect:
1228 * @source: the source
1229 * @callback_data: pointer to callback data "object"
1230 * @callback_funcs: functions for reference counting @callback_data
1231 * and getting the callback and data
1233 * Sets the callback function storing the data as a refcounted callback
1234 * "object". This is used internally. Note that calling
1235 * g_source_set_callback_indirect() assumes
1236 * an initial reference count on @callback_data, and thus
1237 * @callback_funcs->unref will eventually be called once more
1238 * than @callback_funcs->ref.
1241 g_source_set_callback_indirect (GSource *source,
1242 gpointer callback_data,
1243 GSourceCallbackFuncs *callback_funcs)
1245 GMainContext *context;
1246 gpointer old_cb_data;
1247 GSourceCallbackFuncs *old_cb_funcs;
1249 g_return_if_fail (source != NULL);
1250 g_return_if_fail (callback_funcs != NULL || callback_data == NULL);
1252 context = source->context;
1255 LOCK_CONTEXT (context);
1257 old_cb_data = source->callback_data;
1258 old_cb_funcs = source->callback_funcs;
1260 source->callback_data = callback_data;
1261 source->callback_funcs = callback_funcs;
1264 UNLOCK_CONTEXT (context);
1267 old_cb_funcs->unref (old_cb_data);
1271 g_source_callback_ref (gpointer cb_data)
1273 GSourceCallback *callback = cb_data;
1275 callback->ref_count++;
1280 g_source_callback_unref (gpointer cb_data)
1282 GSourceCallback *callback = cb_data;
1284 callback->ref_count--;
1285 if (callback->ref_count == 0)
1287 if (callback->notify)
1288 callback->notify (callback->data);
1294 g_source_callback_get (gpointer cb_data,
1299 GSourceCallback *callback = cb_data;
1301 *func = callback->func;
1302 *data = callback->data;
1305 static GSourceCallbackFuncs g_source_callback_funcs = {
1306 g_source_callback_ref,
1307 g_source_callback_unref,
1308 g_source_callback_get,
1312 * g_source_set_callback:
1313 * @source: the source
1314 * @func: a callback function
1315 * @data: the data to pass to callback function
1316 * @notify: a function to call when @data is no longer in use, or %NULL.
1318 * Sets the callback function for a source. The callback for a source is
1319 * called from the source's dispatch function.
1321 * The exact type of @func depends on the type of source; ie. you
1322 * should not count on @func being called with @data as its first
1325 * Typically, you won't use this function. Instead use functions specific
1326 * to the type of source you are using.
1329 g_source_set_callback (GSource *source,
1332 GDestroyNotify notify)
1334 GSourceCallback *new_callback;
1336 g_return_if_fail (source != NULL);
1338 new_callback = g_new (GSourceCallback, 1);
1340 new_callback->ref_count = 1;
1341 new_callback->func = func;
1342 new_callback->data = data;
1343 new_callback->notify = notify;
1345 g_source_set_callback_indirect (source, new_callback, &g_source_callback_funcs);
1350 * g_source_set_funcs:
1351 * @source: a #GSource
1352 * @funcs: the new #GSourceFuncs
1354 * Sets the source functions (can be used to override
1355 * default implementations) of an unattached source.
1360 g_source_set_funcs (GSource *source,
1361 GSourceFuncs *funcs)
1363 g_return_if_fail (source != NULL);
1364 g_return_if_fail (source->context == NULL);
1365 g_return_if_fail (source->ref_count > 0);
1366 g_return_if_fail (funcs != NULL);
1368 source->source_funcs = funcs;
1372 g_source_set_priority_unlocked (GSource *source,
1373 GMainContext *context,
1378 source->priority = priority;
1382 /* Remove the source from the context's source and then
1383 * add it back so it is sorted in the correct place
1385 g_source_list_remove (source, source->context);
1386 g_source_list_add (source, source->context);
1388 if (!SOURCE_BLOCKED (source))
1390 tmp_list = source->poll_fds;
1393 g_main_context_remove_poll_unlocked (context, tmp_list->data);
1394 g_main_context_add_poll_unlocked (context, priority, tmp_list->data);
1396 tmp_list = tmp_list->next;
1401 if (source->priv && source->priv->child_sources)
1403 tmp_list = source->priv->child_sources;
1406 g_source_set_priority_unlocked (tmp_list->data, context, priority);
1407 tmp_list = tmp_list->next;
1413 * g_source_set_priority:
1414 * @source: a #GSource
1415 * @priority: the new priority.
1417 * Sets the priority of a source. While the main loop is being run, a
1418 * source will be dispatched if it is ready to be dispatched and no
1419 * sources at a higher (numerically smaller) priority are ready to be
1423 g_source_set_priority (GSource *source,
1426 GMainContext *context;
1428 g_return_if_fail (source != NULL);
1430 context = source->context;
1433 LOCK_CONTEXT (context);
1434 g_source_set_priority_unlocked (source, context, priority);
1436 UNLOCK_CONTEXT (source->context);
1440 * g_source_get_priority:
1441 * @source: a #GSource
1443 * Gets the priority of a source.
1445 * Return value: the priority of the source
1448 g_source_get_priority (GSource *source)
1450 g_return_val_if_fail (source != NULL, 0);
1452 return source->priority;
1456 * g_source_set_can_recurse:
1457 * @source: a #GSource
1458 * @can_recurse: whether recursion is allowed for this source
1460 * Sets whether a source can be called recursively. If @can_recurse is
1461 * %TRUE, then while the source is being dispatched then this source
1462 * will be processed normally. Otherwise, all processing of this
1463 * source is blocked until the dispatch function returns.
1466 g_source_set_can_recurse (GSource *source,
1467 gboolean can_recurse)
1469 GMainContext *context;
1471 g_return_if_fail (source != NULL);
1473 context = source->context;
1476 LOCK_CONTEXT (context);
1479 source->flags |= G_SOURCE_CAN_RECURSE;
1481 source->flags &= ~G_SOURCE_CAN_RECURSE;
1484 UNLOCK_CONTEXT (context);
1488 * g_source_get_can_recurse:
1489 * @source: a #GSource
1491 * Checks whether a source is allowed to be called recursively.
1492 * see g_source_set_can_recurse().
1494 * Return value: whether recursion is allowed.
1497 g_source_get_can_recurse (GSource *source)
1499 g_return_val_if_fail (source != NULL, FALSE);
1501 return (source->flags & G_SOURCE_CAN_RECURSE) != 0;
1506 * g_source_set_name:
1507 * @source: a #GSource
1508 * @name: debug name for the source
1510 * Sets a name for the source, used in debugging and profiling.
1511 * The name defaults to #NULL.
1513 * The source name should describe in a human-readable way
1514 * what the source does. For example, "X11 event queue"
1515 * or "GTK+ repaint idle handler" or whatever it is.
1517 * It is permitted to call this function multiple times, but is not
1518 * recommended due to the potential performance impact. For example,
1519 * one could change the name in the "check" function of a #GSourceFuncs
1520 * to include details like the event type in the source name.
1525 g_source_set_name (GSource *source,
1528 g_return_if_fail (source != NULL);
1530 /* setting back to NULL is allowed, just because it's
1531 * weird if get_name can return NULL but you can't
1535 g_free (source->name);
1536 source->name = g_strdup (name);
1540 * g_source_get_name:
1541 * @source: a #GSource
1543 * Gets a name for the source, used in debugging and profiling.
1544 * The name may be #NULL if it has never been set with
1545 * g_source_set_name().
1547 * Return value: the name of the source
1551 g_source_get_name (GSource *source)
1553 g_return_val_if_fail (source != NULL, NULL);
1555 return source->name;
1559 * g_source_set_name_by_id:
1560 * @tag: a #GSource ID
1561 * @name: debug name for the source
1563 * Sets the name of a source using its ID.
1565 * This is a convenience utility to set source names from the return
1566 * value of g_idle_add(), g_timeout_add(), etc.
1571 g_source_set_name_by_id (guint tag,
1576 g_return_if_fail (tag > 0);
1578 source = g_main_context_find_source_by_id (NULL, tag);
1582 g_source_set_name (source, name);
1588 * @source: a #GSource
1590 * Increases the reference count on a source by one.
1592 * Return value: @source
1595 g_source_ref (GSource *source)
1597 GMainContext *context;
1599 g_return_val_if_fail (source != NULL, NULL);
1601 context = source->context;
1604 LOCK_CONTEXT (context);
1606 source->ref_count++;
1609 UNLOCK_CONTEXT (context);
1614 /* g_source_unref() but possible to call within context lock
1617 g_source_unref_internal (GSource *source,
1618 GMainContext *context,
1621 gpointer old_cb_data = NULL;
1622 GSourceCallbackFuncs *old_cb_funcs = NULL;
1624 g_return_if_fail (source != NULL);
1626 if (!have_lock && context)
1627 LOCK_CONTEXT (context);
1629 source->ref_count--;
1630 if (source->ref_count == 0)
1632 old_cb_data = source->callback_data;
1633 old_cb_funcs = source->callback_funcs;
1635 source->callback_data = NULL;
1636 source->callback_funcs = NULL;
1640 if (!SOURCE_DESTROYED (source))
1641 g_warning (G_STRLOC ": ref_count == 0, but source was still attached to a context!");
1642 g_source_list_remove (source, context);
1645 if (source->source_funcs->finalize)
1648 UNLOCK_CONTEXT (context);
1649 source->source_funcs->finalize (source);
1651 LOCK_CONTEXT (context);
1654 g_free (source->name);
1655 source->name = NULL;
1657 g_slist_free (source->poll_fds);
1658 source->poll_fds = NULL;
1662 g_slice_free (GSourcePrivate, source->priv);
1663 source->priv = NULL;
1669 if (!have_lock && context)
1670 UNLOCK_CONTEXT (context);
1675 UNLOCK_CONTEXT (context);
1677 old_cb_funcs->unref (old_cb_data);
1680 LOCK_CONTEXT (context);
1686 * @source: a #GSource
1688 * Decreases the reference count of a source by one. If the
1689 * resulting reference count is zero the source and associated
1690 * memory will be destroyed.
1693 g_source_unref (GSource *source)
1695 g_return_if_fail (source != NULL);
1697 g_source_unref_internal (source, source->context, FALSE);
1701 * g_main_context_find_source_by_id:
1702 * @context: a #GMainContext (if %NULL, the default context will be used)
1703 * @source_id: the source ID, as returned by g_source_get_id().
1705 * Finds a #GSource given a pair of context and ID.
1707 * Return value: (transfer none): the #GSource if found, otherwise, %NULL
1710 g_main_context_find_source_by_id (GMainContext *context,
1715 g_return_val_if_fail (source_id > 0, NULL);
1717 if (context == NULL)
1718 context = g_main_context_default ();
1720 LOCK_CONTEXT (context);
1722 source = context->source_list;
1725 if (!SOURCE_DESTROYED (source) &&
1726 source->source_id == source_id)
1728 source = source->next;
1731 UNLOCK_CONTEXT (context);
1737 * g_main_context_find_source_by_funcs_user_data:
1738 * @context: a #GMainContext (if %NULL, the default context will be used).
1739 * @funcs: the @source_funcs passed to g_source_new().
1740 * @user_data: the user data from the callback.
1742 * Finds a source with the given source functions and user data. If
1743 * multiple sources exist with the same source function and user data,
1744 * the first one found will be returned.
1746 * Return value: (transfer none): the source, if one was found, otherwise %NULL
1749 g_main_context_find_source_by_funcs_user_data (GMainContext *context,
1750 GSourceFuncs *funcs,
1755 g_return_val_if_fail (funcs != NULL, NULL);
1757 if (context == NULL)
1758 context = g_main_context_default ();
1760 LOCK_CONTEXT (context);
1762 source = context->source_list;
1765 if (!SOURCE_DESTROYED (source) &&
1766 source->source_funcs == funcs &&
1767 source->callback_funcs)
1769 GSourceFunc callback;
1770 gpointer callback_data;
1772 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
1774 if (callback_data == user_data)
1777 source = source->next;
1780 UNLOCK_CONTEXT (context);
1786 * g_main_context_find_source_by_user_data:
1787 * @context: a #GMainContext
1788 * @user_data: the user_data for the callback.
1790 * Finds a source with the given user data for the callback. If
1791 * multiple sources exist with the same user data, the first
1792 * one found will be returned.
1794 * Return value: (transfer none): the source, if one was found, otherwise %NULL
1797 g_main_context_find_source_by_user_data (GMainContext *context,
1802 if (context == NULL)
1803 context = g_main_context_default ();
1805 LOCK_CONTEXT (context);
1807 source = context->source_list;
1810 if (!SOURCE_DESTROYED (source) &&
1811 source->callback_funcs)
1813 GSourceFunc callback;
1814 gpointer callback_data = NULL;
1816 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
1818 if (callback_data == user_data)
1821 source = source->next;
1824 UNLOCK_CONTEXT (context);
1831 * @tag: the ID of the source to remove.
1833 * Removes the source with the given id from the default main context.
1835 * a #GSource is given by g_source_get_id(), or will be returned by the
1836 * functions g_source_attach(), g_idle_add(), g_idle_add_full(),
1837 * g_timeout_add(), g_timeout_add_full(), g_child_watch_add(),
1838 * g_child_watch_add_full(), g_io_add_watch(), and g_io_add_watch_full().
1840 * See also g_source_destroy(). You must use g_source_destroy() for sources
1841 * added to a non-default main context.
1843 * Return value: %TRUE if the source was found and removed.
1846 g_source_remove (guint tag)
1850 g_return_val_if_fail (tag > 0, FALSE);
1852 source = g_main_context_find_source_by_id (NULL, tag);
1854 g_source_destroy (source);
1856 return source != NULL;
1860 * g_source_remove_by_user_data:
1861 * @user_data: the user_data for the callback.
1863 * Removes a source from the default main loop context given the user
1864 * data for the callback. If multiple sources exist with the same user
1865 * data, only one will be destroyed.
1867 * Return value: %TRUE if a source was found and removed.
1870 g_source_remove_by_user_data (gpointer user_data)
1874 source = g_main_context_find_source_by_user_data (NULL, user_data);
1877 g_source_destroy (source);
1885 * g_source_remove_by_funcs_user_data:
1886 * @funcs: The @source_funcs passed to g_source_new()
1887 * @user_data: the user data for the callback
1889 * Removes a source from the default main loop context given the
1890 * source functions and user data. If multiple sources exist with the
1891 * same source functions and user data, only one will be destroyed.
1893 * Return value: %TRUE if a source was found and removed.
1896 g_source_remove_by_funcs_user_data (GSourceFuncs *funcs,
1901 g_return_val_if_fail (funcs != NULL, FALSE);
1903 source = g_main_context_find_source_by_funcs_user_data (NULL, funcs, user_data);
1906 g_source_destroy (source);
1914 * g_get_current_time:
1915 * @result: #GTimeVal structure in which to store current time.
1917 * Equivalent to the UNIX gettimeofday() function, but portable.
1919 * You may find g_get_real_time() to be more convenient.
1922 g_get_current_time (GTimeVal *result)
1927 g_return_if_fail (result != NULL);
1929 /*this is required on alpha, there the timeval structs are int's
1930 not longs and a cast only would fail horribly*/
1931 gettimeofday (&r, NULL);
1932 result->tv_sec = r.tv_sec;
1933 result->tv_usec = r.tv_usec;
1938 g_return_if_fail (result != NULL);
1940 GetSystemTimeAsFileTime (&ft);
1941 memmove (&time64, &ft, sizeof (FILETIME));
1943 /* Convert from 100s of nanoseconds since 1601-01-01
1944 * to Unix epoch. Yes, this is Y2038 unsafe.
1946 time64 -= G_GINT64_CONSTANT (116444736000000000);
1949 result->tv_sec = time64 / 1000000;
1950 result->tv_usec = time64 % 1000000;
1957 * Queries the system wall-clock time.
1959 * This call is functionally equivalent to g_get_current_time() except
1960 * that the return value is often more convenient than dealing with a
1963 * You should only use this call if you are actually interested in the real
1964 * wall-clock time. g_get_monotonic_time() is probably more useful for
1965 * measuring intervals.
1967 * Returns: the number of microseconds since January 1, 1970 UTC.
1972 g_get_real_time (void)
1976 g_get_current_time (&tv);
1978 return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec;
1982 static ULONGLONG (*g_GetTickCount64) (void) = NULL;
1983 static guint32 g_win32_tick_epoch = 0;
1985 G_GNUC_INTERNAL void
1986 g_clock_win32_init (void)
1990 g_GetTickCount64 = NULL;
1991 kernel32 = GetModuleHandle ("KERNEL32.DLL");
1992 if (kernel32 != NULL)
1993 g_GetTickCount64 = (void *) GetProcAddress (kernel32, "GetTickCount64");
1994 g_win32_tick_epoch = ((guint32)GetTickCount()) >> 31;
1999 * g_get_monotonic_time:
2001 * Queries the system monotonic time, if available.
2003 * On POSIX systems with clock_gettime() and <literal>CLOCK_MONOTONIC</literal> this call
2004 * is a very shallow wrapper for that. Otherwise, we make a best effort
2005 * that probably involves returning the wall clock time (with at least
2006 * microsecond accuracy, subject to the limitations of the OS kernel).
2008 * It's important to note that POSIX <literal>CLOCK_MONOTONIC</literal> does
2009 * not count time spent while the machine is suspended.
2011 * On Windows, "limitations of the OS kernel" is a rather substantial
2012 * statement. Depending on the configuration of the system, the wall
2013 * clock time is updated as infrequently as 64 times a second (which
2014 * is approximately every 16ms). Also, on XP (but not on Vista or later)
2015 * the monotonic clock is locally monotonic, but may differ in exact
2016 * value between processes due to timer wrap handling.
2018 * Returns: the monotonic time, in microseconds
2023 g_get_monotonic_time (void)
2025 #ifdef HAVE_CLOCK_GETTIME
2026 /* librt clock_gettime() is our first choice */
2029 #ifdef CLOCK_MONOTONIC
2030 clock_gettime (CLOCK_MONOTONIC, &ts);
2032 clock_gettime (CLOCK_REALTIME, &ts);
2035 /* In theory monotonic time can have any epoch.
2037 * glib presently assumes the following:
2039 * 1) The epoch comes some time after the birth of Jesus of Nazareth, but
2040 * not more than 10000 years later.
2042 * 2) The current time also falls sometime within this range.
2044 * These two reasonable assumptions leave us with a maximum deviation from
2045 * the epoch of 10000 years, or 315569520000000000 seconds.
2047 * If we restrict ourselves to this range then the number of microseconds
2048 * will always fit well inside the constraints of a int64 (by a factor of
2051 * If you actually hit the following assertion, probably you should file a
2052 * bug against your operating system for being excessively silly.
2054 g_assert (G_GINT64_CONSTANT (-315569520000000000) < ts.tv_sec &&
2055 ts.tv_sec < G_GINT64_CONSTANT (315569520000000000));
2057 return (((gint64) ts.tv_sec) * 1000000) + (ts.tv_nsec / 1000);
2059 #elif defined (G_OS_WIN32)
2063 /* There are four sources for the monotonic time on Windows:
2065 * Three are based on a (1 msec accuracy, but only read periodically) clock chip:
2066 * - GetTickCount (GTC)
2067 * 32bit msec counter, updated each ~15msec, wraps in ~50 days
2068 * - GetTickCount64 (GTC64)
2069 * Same as GetTickCount, but extended to 64bit, so no wrap
2070 * Only available in Vista or later
2071 * - timeGetTime (TGT)
2072 * similar to GetTickCount by default: 15msec, 50 day wrap.
2073 * available in winmm.dll (thus known as the multimedia timers)
2074 * However apps can raise the system timer clock frequency using timeBeginPeriod()
2075 * increasing the accuracy up to 1 msec, at a cost in general system performance
2078 * One is based on high precision clocks:
2079 * - QueryPrecisionCounter (QPC)
2080 * This has much higher accuracy, but is not guaranteed monotonic, and
2081 * has lots of complications like clock jumps and different times on different
2082 * CPUs. It also has lower long term accuracy (i.e. it will drift compared to
2083 * the low precision clocks.
2085 * Additionally, the precision available in the timer-based wakeup such as
2086 * MsgWaitForMultipleObjectsEx (which is what the mainloop is based on) is based
2087 * on the TGT resolution, so by default it is ~15msec, but can be increased by apps.
2089 * The QPC timer has too many issues to be used as is. The only way it could be used
2090 * is to use it to interpolate the lower precision clocks. Firefox does something like
2092 * https://bugzilla.mozilla.org/show_bug.cgi?id=363258
2094 * However this seems quite complicated, so we're not doing this right now.
2096 * The approach we take instead is to use the TGT timer, extending it to 64bit
2097 * either by using the GTC64 value, or if that is not available, a process local
2098 * time epoch that we increment when we detect a timer wrap (assumes that we read
2099 * the time at least once every 50 days).
2102 * - We have a globally consistent monotonic clock on Vista and later
2103 * - We have a locally monotonic clock on XP
2104 * - Apps that need higher precision in timeouts and clock reads can call
2105 * timeBeginPeriod() to increase it as much as they want
2108 if (g_GetTickCount64 != NULL)
2110 guint32 ticks_as_32bit;
2112 ticks = g_GetTickCount64 ();
2113 ticks32 = timeGetTime();
2115 /* GTC64 and TGT are sampled at different times, however they
2116 * have the same base and source (msecs since system boot).
2117 * They can differ by as much as -16 to +16 msecs.
2118 * We can't just inject the low bits into the 64bit counter
2119 * as one of the counters can have wrapped in 32bit space and
2120 * the other not. Instead we calculate the signed difference
2121 * in 32bit space and apply that difference to the 64bit counter.
2123 ticks_as_32bit = (guint32)ticks;
2125 /* We could do some 2's complement hack, but we play it safe */
2126 if (ticks32 - ticks_as_32bit <= G_MAXINT32)
2127 ticks += ticks32 - ticks_as_32bit;
2129 ticks -= ticks_as_32bit - ticks32;
2135 epoch = g_atomic_int_get (&g_win32_tick_epoch);
2137 /* Must read ticks after the epoch. Then we're guaranteed
2138 * that the ticks value we read is higher or equal to any
2139 * previous ones that lead to the writing of the epoch.
2141 ticks32 = timeGetTime();
2143 /* We store the MSB of the current time as the LSB
2144 * of the epoch. Comparing these bits lets us detect when
2145 * the 32bit counter has wrapped so we can increase the
2148 * This will work as long as this function is called at
2149 * least once every ~24 days, which is half the wrap time
2150 * of a 32bit msec counter. I think this is pretty likely.
2152 * Note that g_win32_tick_epoch is a process local state,
2153 * so the monotonic clock will not be the same between
2156 if ((ticks32 >> 31) != (epoch & 1))
2159 g_atomic_int_set (&g_win32_tick_epoch, epoch);
2163 ticks = (guint64)ticks32 | ((guint64)epoch) << 31;
2166 return ticks * 1000;
2168 #else /* !HAVE_CLOCK_GETTIME && ! G_OS_WIN32*/
2172 g_get_current_time (&tv);
2174 return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec;
2179 g_main_dispatch_free (gpointer dispatch)
2181 g_slice_free (GMainDispatch, dispatch);
2184 /* Running the main loop */
2186 static GMainDispatch *
2189 static GPrivate depth_private = G_PRIVATE_INIT (g_main_dispatch_free);
2190 GMainDispatch *dispatch;
2192 dispatch = g_private_get (&depth_private);
2196 dispatch = g_slice_new0 (GMainDispatch);
2197 g_private_set (&depth_private, dispatch);
2206 * Returns the depth of the stack of calls to
2207 * g_main_context_dispatch() on any #GMainContext in the current thread.
2208 * That is, when called from the toplevel, it gives 0. When
2209 * called from within a callback from g_main_context_iteration()
2210 * (or g_main_loop_run(), etc.) it returns 1. When called from within
2211 * a callback to a recursive call to g_main_context_iteration(),
2212 * it returns 2. And so forth.
2214 * This function is useful in a situation like the following:
2215 * Imagine an extremely simple "garbage collected" system.
2218 * static GList *free_list;
2221 * allocate_memory (gsize size)
2223 * gpointer result = g_malloc (size);
2224 * free_list = g_list_prepend (free_list, result);
2229 * free_allocated_memory (void)
2232 * for (l = free_list; l; l = l->next);
2234 * g_list_free (free_list);
2242 * g_main_context_iteration (NULL, TRUE);
2243 * free_allocated_memory();
2247 * This works from an application, however, if you want to do the same
2248 * thing from a library, it gets more difficult, since you no longer
2249 * control the main loop. You might think you can simply use an idle
2250 * function to make the call to free_allocated_memory(), but that
2251 * doesn't work, since the idle function could be called from a
2252 * recursive callback. This can be fixed by using g_main_depth()
2256 * allocate_memory (gsize size)
2258 * FreeListBlock *block = g_new (FreeListBlock, 1);
2259 * block->mem = g_malloc (size);
2260 * block->depth = g_main_depth ();
2261 * free_list = g_list_prepend (free_list, block);
2262 * return block->mem;
2266 * free_allocated_memory (void)
2270 * int depth = g_main_depth ();
2271 * for (l = free_list; l; );
2273 * GList *next = l->next;
2274 * FreeListBlock *block = l->data;
2275 * if (block->depth > depth)
2277 * g_free (block->mem);
2279 * free_list = g_list_delete_link (free_list, l);
2287 * There is a temptation to use g_main_depth() to solve
2288 * problems with reentrancy. For instance, while waiting for data
2289 * to be received from the network in response to a menu item,
2290 * the menu item might be selected again. It might seem that
2291 * one could make the menu item's callback return immediately
2292 * and do nothing if g_main_depth() returns a value greater than 1.
2293 * However, this should be avoided since the user then sees selecting
2294 * the menu item do nothing. Furthermore, you'll find yourself adding
2295 * these checks all over your code, since there are doubtless many,
2296 * many things that the user could do. Instead, you can use the
2297 * following techniques:
2302 * Use gtk_widget_set_sensitive() or modal dialogs to prevent
2303 * the user from interacting with elements while the main
2304 * loop is recursing.
2309 * Avoid main loop recursion in situations where you can't handle
2310 * arbitrary callbacks. Instead, structure your code so that you
2311 * simply return to the main loop and then get called again when
2312 * there is more work to do.
2317 * Return value: The main loop recursion level in the current thread
2322 GMainDispatch *dispatch = get_dispatch ();
2323 return dispatch->depth;
2327 * g_main_current_source:
2329 * Returns the currently firing source for this thread.
2331 * Return value: (transfer none): The currently firing source or %NULL.
2336 g_main_current_source (void)
2338 GMainDispatch *dispatch = get_dispatch ();
2339 return dispatch->dispatching_sources ? dispatch->dispatching_sources->data : NULL;
2343 * g_source_is_destroyed:
2344 * @source: a #GSource
2346 * Returns whether @source has been destroyed.
2348 * This is important when you operate upon your objects
2349 * from within idle handlers, but may have freed the object
2350 * before the dispatch of your idle handler.
2354 * idle_callback (gpointer data)
2356 * SomeWidget *self = data;
2358 * GDK_THREADS_ENTER (<!-- -->);
2359 * /<!-- -->* do stuff with self *<!-- -->/
2360 * self->idle_id = 0;
2361 * GDK_THREADS_LEAVE (<!-- -->);
2363 * return G_SOURCE_REMOVE;
2367 * some_widget_do_stuff_later (SomeWidget *self)
2369 * self->idle_id = g_idle_add (idle_callback, self);
2373 * some_widget_finalize (GObject *object)
2375 * SomeWidget *self = SOME_WIDGET (object);
2377 * if (self->idle_id)
2378 * g_source_remove (self->idle_id);
2380 * G_OBJECT_CLASS (parent_class)->finalize (object);
2384 * This will fail in a multi-threaded application if the
2385 * widget is destroyed before the idle handler fires due
2386 * to the use after free in the callback. A solution, to
2387 * this particular problem, is to check to if the source
2388 * has already been destroy within the callback.
2392 * idle_callback (gpointer data)
2394 * SomeWidget *self = data;
2396 * GDK_THREADS_ENTER ();
2397 * if (!g_source_is_destroyed (g_main_current_source ()))
2399 * /<!-- -->* do stuff with self *<!-- -->/
2401 * GDK_THREADS_LEAVE ();
2407 * Return value: %TRUE if the source has been destroyed
2412 g_source_is_destroyed (GSource *source)
2414 return SOURCE_DESTROYED (source);
2417 /* Temporarily remove all this source's file descriptors from the
2418 * poll(), so that if data comes available for one of the file descriptors
2419 * we don't continually spin in the poll()
2421 /* HOLDS: source->context's lock */
2423 block_source (GSource *source)
2427 g_return_if_fail (!SOURCE_BLOCKED (source));
2429 tmp_list = source->poll_fds;
2432 g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
2433 tmp_list = tmp_list->next;
2437 /* HOLDS: source->context's lock */
2439 unblock_source (GSource *source)
2443 g_return_if_fail (!SOURCE_BLOCKED (source)); /* Source already unblocked */
2444 g_return_if_fail (!SOURCE_DESTROYED (source));
2446 tmp_list = source->poll_fds;
2449 g_main_context_add_poll_unlocked (source->context, source->priority, tmp_list->data);
2450 tmp_list = tmp_list->next;
2454 /* HOLDS: context's lock */
2456 g_main_dispatch (GMainContext *context)
2458 GMainDispatch *current = get_dispatch ();
2461 for (i = 0; i < context->pending_dispatches->len; i++)
2463 GSource *source = context->pending_dispatches->pdata[i];
2465 context->pending_dispatches->pdata[i] = NULL;
2468 source->flags &= ~G_SOURCE_READY;
2470 if (!SOURCE_DESTROYED (source))
2472 gboolean was_in_call;
2473 gpointer user_data = NULL;
2474 GSourceFunc callback = NULL;
2475 GSourceCallbackFuncs *cb_funcs;
2477 gboolean need_destroy;
2479 gboolean (*dispatch) (GSource *,
2482 GSList current_source_link;
2484 dispatch = source->source_funcs->dispatch;
2485 cb_funcs = source->callback_funcs;
2486 cb_data = source->callback_data;
2489 cb_funcs->ref (cb_data);
2491 if ((source->flags & G_SOURCE_CAN_RECURSE) == 0)
2492 block_source (source);
2494 was_in_call = source->flags & G_HOOK_FLAG_IN_CALL;
2495 source->flags |= G_HOOK_FLAG_IN_CALL;
2498 cb_funcs->get (cb_data, source, &callback, &user_data);
2500 UNLOCK_CONTEXT (context);
2503 /* The on-stack allocation of the GSList is unconventional, but
2504 * we know that the lifetime of the link is bounded to this
2505 * function as the link is kept in a thread specific list and
2506 * not manipulated outside of this function and its descendants.
2507 * Avoiding the overhead of a g_slist_alloc() is useful as many
2508 * applications do little more than dispatch events.
2510 * This is a performance hack - do not revert to g_slist_prepend()!
2512 current_source_link.data = source;
2513 current_source_link.next = current->dispatching_sources;
2514 current->dispatching_sources = ¤t_source_link;
2515 need_destroy = ! dispatch (source,
2518 g_assert (current->dispatching_sources == ¤t_source_link);
2519 current->dispatching_sources = current_source_link.next;
2523 cb_funcs->unref (cb_data);
2525 LOCK_CONTEXT (context);
2528 source->flags &= ~G_HOOK_FLAG_IN_CALL;
2530 if ((source->flags & G_SOURCE_CAN_RECURSE) == 0 &&
2531 !SOURCE_DESTROYED (source))
2532 unblock_source (source);
2534 /* Note: this depends on the fact that we can't switch
2535 * sources from one main context to another
2537 if (need_destroy && !SOURCE_DESTROYED (source))
2539 g_assert (source->context == context);
2540 g_source_destroy_internal (source, context, TRUE);
2544 SOURCE_UNREF (source, context);
2547 g_ptr_array_set_size (context->pending_dispatches, 0);
2550 /* Holds context's lock */
2551 static inline GSource *
2552 next_valid_source (GMainContext *context,
2555 GSource *new_source = source ? source->next : context->source_list;
2559 if (!SOURCE_DESTROYED (new_source))
2561 new_source->ref_count++;
2565 new_source = new_source->next;
2569 SOURCE_UNREF (source, context);
2575 * g_main_context_acquire:
2576 * @context: a #GMainContext
2578 * Tries to become the owner of the specified context.
2579 * If some other thread is the owner of the context,
2580 * returns %FALSE immediately. Ownership is properly
2581 * recursive: the owner can require ownership again
2582 * and will release ownership when g_main_context_release()
2583 * is called as many times as g_main_context_acquire().
2585 * You must be the owner of a context before you
2586 * can call g_main_context_prepare(), g_main_context_query(),
2587 * g_main_context_check(), g_main_context_dispatch().
2589 * Return value: %TRUE if the operation succeeded, and
2590 * this thread is now the owner of @context.
2593 g_main_context_acquire (GMainContext *context)
2595 gboolean result = FALSE;
2596 GThread *self = G_THREAD_SELF;
2598 if (context == NULL)
2599 context = g_main_context_default ();
2601 LOCK_CONTEXT (context);
2603 if (!context->owner)
2605 context->owner = self;
2606 g_assert (context->owner_count == 0);
2609 if (context->owner == self)
2611 context->owner_count++;
2615 UNLOCK_CONTEXT (context);
2621 * g_main_context_release:
2622 * @context: a #GMainContext
2624 * Releases ownership of a context previously acquired by this thread
2625 * with g_main_context_acquire(). If the context was acquired multiple
2626 * times, the ownership will be released only when g_main_context_release()
2627 * is called as many times as it was acquired.
2630 g_main_context_release (GMainContext *context)
2632 if (context == NULL)
2633 context = g_main_context_default ();
2635 LOCK_CONTEXT (context);
2637 context->owner_count--;
2638 if (context->owner_count == 0)
2640 context->owner = NULL;
2642 if (context->waiters)
2644 GMainWaiter *waiter = context->waiters->data;
2645 gboolean loop_internal_waiter = (waiter->mutex == &context->mutex);
2646 context->waiters = g_slist_delete_link (context->waiters,
2648 if (!loop_internal_waiter)
2649 g_mutex_lock (waiter->mutex);
2651 g_cond_signal (waiter->cond);
2653 if (!loop_internal_waiter)
2654 g_mutex_unlock (waiter->mutex);
2658 UNLOCK_CONTEXT (context);
2662 * g_main_context_wait:
2663 * @context: a #GMainContext
2664 * @cond: a condition variable
2665 * @mutex: a mutex, currently held
2667 * Tries to become the owner of the specified context,
2668 * as with g_main_context_acquire(). But if another thread
2669 * is the owner, atomically drop @mutex and wait on @cond until
2670 * that owner releases ownership or until @cond is signaled, then
2671 * try again (once) to become the owner.
2673 * Return value: %TRUE if the operation succeeded, and
2674 * this thread is now the owner of @context.
2677 g_main_context_wait (GMainContext *context,
2681 gboolean result = FALSE;
2682 GThread *self = G_THREAD_SELF;
2683 gboolean loop_internal_waiter;
2685 if (context == NULL)
2686 context = g_main_context_default ();
2688 loop_internal_waiter = (mutex == &context->mutex);
2690 if (!loop_internal_waiter)
2691 LOCK_CONTEXT (context);
2693 if (context->owner && context->owner != self)
2698 waiter.mutex = mutex;
2700 context->waiters = g_slist_append (context->waiters, &waiter);
2702 if (!loop_internal_waiter)
2703 UNLOCK_CONTEXT (context);
2704 g_cond_wait (cond, mutex);
2705 if (!loop_internal_waiter)
2706 LOCK_CONTEXT (context);
2708 context->waiters = g_slist_remove (context->waiters, &waiter);
2711 if (!context->owner)
2713 context->owner = self;
2714 g_assert (context->owner_count == 0);
2717 if (context->owner == self)
2719 context->owner_count++;
2723 if (!loop_internal_waiter)
2724 UNLOCK_CONTEXT (context);
2730 * g_main_context_prepare:
2731 * @context: a #GMainContext
2732 * @priority: location to store priority of highest priority
2733 * source already ready.
2735 * Prepares to poll sources within a main loop. The resulting information
2736 * for polling is determined by calling g_main_context_query ().
2738 * Return value: %TRUE if some source is ready to be dispatched
2742 g_main_context_prepare (GMainContext *context,
2747 gint current_priority = G_MAXINT;
2750 if (context == NULL)
2751 context = g_main_context_default ();
2753 LOCK_CONTEXT (context);
2755 context->time_is_fresh = FALSE;
2757 if (context->in_check_or_prepare)
2759 g_warning ("g_main_context_prepare() called recursively from within a source's check() or "
2760 "prepare() member.");
2761 UNLOCK_CONTEXT (context);
2766 /* If recursing, finish up current dispatch, before starting over */
2767 if (context->pending_dispatches)
2770 g_main_dispatch (context, ¤t_time);
2772 UNLOCK_CONTEXT (context);
2777 /* If recursing, clear list of pending dispatches */
2779 for (i = 0; i < context->pending_dispatches->len; i++)
2781 if (context->pending_dispatches->pdata[i])
2782 SOURCE_UNREF ((GSource *)context->pending_dispatches->pdata[i], context);
2784 g_ptr_array_set_size (context->pending_dispatches, 0);
2786 /* Prepare all sources */
2788 context->timeout = -1;
2790 source = next_valid_source (context, NULL);
2793 gint source_timeout = -1;
2795 if ((n_ready > 0) && (source->priority > current_priority))
2797 SOURCE_UNREF (source, context);
2800 if (SOURCE_BLOCKED (source))
2803 if (!(source->flags & G_SOURCE_READY))
2806 gboolean (*prepare) (GSource *source,
2809 prepare = source->source_funcs->prepare;
2810 context->in_check_or_prepare++;
2811 UNLOCK_CONTEXT (context);
2813 result = (*prepare) (source, &source_timeout);
2815 LOCK_CONTEXT (context);
2816 context->in_check_or_prepare--;
2820 GSource *ready_source = source;
2822 while (ready_source)
2824 ready_source->flags |= G_SOURCE_READY;
2825 ready_source = ready_source->priv ? ready_source->priv->parent_source : NULL;
2830 if (source->flags & G_SOURCE_READY)
2833 current_priority = source->priority;
2834 context->timeout = 0;
2837 if (source_timeout >= 0)
2839 if (context->timeout < 0)
2840 context->timeout = source_timeout;
2842 context->timeout = MIN (context->timeout, source_timeout);
2846 source = next_valid_source (context, source);
2849 UNLOCK_CONTEXT (context);
2852 *priority = current_priority;
2854 return (n_ready > 0);
2858 * g_main_context_query:
2859 * @context: a #GMainContext
2860 * @max_priority: maximum priority source to check
2861 * @timeout_: (out): location to store timeout to be used in polling
2862 * @fds: (out caller-allocates) (array length=n_fds): location to
2863 * store #GPollFD records that need to be polled.
2864 * @n_fds: length of @fds.
2866 * Determines information necessary to poll this main loop.
2868 * Return value: the number of records actually stored in @fds,
2869 * or, if more than @n_fds records need to be stored, the number
2870 * of records that need to be stored.
2873 g_main_context_query (GMainContext *context,
2882 LOCK_CONTEXT (context);
2884 pollrec = context->poll_records;
2886 while (pollrec && max_priority >= pollrec->priority)
2888 /* We need to include entries with fd->events == 0 in the array because
2889 * otherwise if the application changes fd->events behind our back and
2890 * makes it non-zero, we'll be out of sync when we check the fds[] array.
2891 * (Changing fd->events after adding an FD wasn't an anticipated use of
2892 * this API, but it occurs in practice.) */
2895 fds[n_poll].fd = pollrec->fd->fd;
2896 /* In direct contradiction to the Unix98 spec, IRIX runs into
2897 * difficulty if you pass in POLLERR, POLLHUP or POLLNVAL
2898 * flags in the events field of the pollfd while it should
2899 * just ignoring them. So we mask them out here.
2901 fds[n_poll].events = pollrec->fd->events & ~(G_IO_ERR|G_IO_HUP|G_IO_NVAL);
2902 fds[n_poll].revents = 0;
2905 pollrec = pollrec->next;
2909 context->poll_changed = FALSE;
2913 *timeout = context->timeout;
2915 context->time_is_fresh = FALSE;
2918 UNLOCK_CONTEXT (context);
2924 * g_main_context_check:
2925 * @context: a #GMainContext
2926 * @max_priority: the maximum numerical priority of sources to check
2927 * @fds: (array length=n_fds): array of #GPollFD's that was passed to
2928 * the last call to g_main_context_query()
2929 * @n_fds: return value of g_main_context_query()
2931 * Passes the results of polling back to the main loop.
2933 * Return value: %TRUE if some sources are ready to be dispatched.
2936 g_main_context_check (GMainContext *context,
2946 LOCK_CONTEXT (context);
2948 if (context->in_check_or_prepare)
2950 g_warning ("g_main_context_check() called recursively from within a source's check() or "
2951 "prepare() member.");
2952 UNLOCK_CONTEXT (context);
2956 if (context->wake_up_rec.events)
2957 g_wakeup_acknowledge (context->wakeup);
2959 /* If the set of poll file descriptors changed, bail out
2960 * and let the main loop rerun
2962 if (context->poll_changed)
2964 UNLOCK_CONTEXT (context);
2968 pollrec = context->poll_records;
2972 if (pollrec->fd->events)
2973 pollrec->fd->revents = fds[i].revents;
2975 pollrec = pollrec->next;
2979 source = next_valid_source (context, NULL);
2982 if ((n_ready > 0) && (source->priority > max_priority))
2984 SOURCE_UNREF (source, context);
2987 if (SOURCE_BLOCKED (source))
2990 if (!(source->flags & G_SOURCE_READY))
2993 gboolean (*check) (GSource *source);
2995 check = source->source_funcs->check;
2997 context->in_check_or_prepare++;
2998 UNLOCK_CONTEXT (context);
3000 result = (*check) (source);
3002 LOCK_CONTEXT (context);
3003 context->in_check_or_prepare--;
3007 GSource *ready_source = source;
3009 while (ready_source)
3011 ready_source->flags |= G_SOURCE_READY;
3012 ready_source = ready_source->priv ? ready_source->priv->parent_source : NULL;
3017 if (source->flags & G_SOURCE_READY)
3019 source->ref_count++;
3020 g_ptr_array_add (context->pending_dispatches, source);
3024 /* never dispatch sources with less priority than the first
3025 * one we choose to dispatch
3027 max_priority = source->priority;
3031 source = next_valid_source (context, source);
3034 UNLOCK_CONTEXT (context);
3040 * g_main_context_dispatch:
3041 * @context: a #GMainContext
3043 * Dispatches all pending sources.
3046 g_main_context_dispatch (GMainContext *context)
3048 LOCK_CONTEXT (context);
3050 if (context->pending_dispatches->len > 0)
3052 g_main_dispatch (context);
3055 UNLOCK_CONTEXT (context);
3058 /* HOLDS context lock */
3060 g_main_context_iterate (GMainContext *context,
3067 gboolean some_ready;
3068 gint nfds, allocated_nfds;
3069 GPollFD *fds = NULL;
3071 UNLOCK_CONTEXT (context);
3073 if (!g_main_context_acquire (context))
3075 gboolean got_ownership;
3077 LOCK_CONTEXT (context);
3082 got_ownership = g_main_context_wait (context,
3090 LOCK_CONTEXT (context);
3092 if (!context->cached_poll_array)
3094 context->cached_poll_array_size = context->n_poll_records;
3095 context->cached_poll_array = g_new (GPollFD, context->n_poll_records);
3098 allocated_nfds = context->cached_poll_array_size;
3099 fds = context->cached_poll_array;
3101 UNLOCK_CONTEXT (context);
3103 g_main_context_prepare (context, &max_priority);
3105 while ((nfds = g_main_context_query (context, max_priority, &timeout, fds,
3106 allocated_nfds)) > allocated_nfds)
3108 LOCK_CONTEXT (context);
3110 context->cached_poll_array_size = allocated_nfds = nfds;
3111 context->cached_poll_array = fds = g_new (GPollFD, nfds);
3112 UNLOCK_CONTEXT (context);
3118 g_main_context_poll (context, timeout, max_priority, fds, nfds);
3120 some_ready = g_main_context_check (context, max_priority, fds, nfds);
3123 g_main_context_dispatch (context);
3125 g_main_context_release (context);
3127 LOCK_CONTEXT (context);
3133 * g_main_context_pending:
3134 * @context: a #GMainContext (if %NULL, the default context will be used)
3136 * Checks if any sources have pending events for the given context.
3138 * Return value: %TRUE if events are pending.
3141 g_main_context_pending (GMainContext *context)
3146 context = g_main_context_default();
3148 LOCK_CONTEXT (context);
3149 retval = g_main_context_iterate (context, FALSE, FALSE, G_THREAD_SELF);
3150 UNLOCK_CONTEXT (context);
3156 * g_main_context_iteration:
3157 * @context: a #GMainContext (if %NULL, the default context will be used)
3158 * @may_block: whether the call may block.
3160 * Runs a single iteration for the given main loop. This involves
3161 * checking to see if any event sources are ready to be processed,
3162 * then if no events sources are ready and @may_block is %TRUE, waiting
3163 * for a source to become ready, then dispatching the highest priority
3164 * events sources that are ready. Otherwise, if @may_block is %FALSE
3165 * sources are not waited to become ready, only those highest priority
3166 * events sources will be dispatched (if any), that are ready at this
3167 * given moment without further waiting.
3169 * Note that even when @may_block is %TRUE, it is still possible for
3170 * g_main_context_iteration() to return %FALSE, since the the wait may
3171 * be interrupted for other reasons than an event source becoming ready.
3173 * Return value: %TRUE if events were dispatched.
3176 g_main_context_iteration (GMainContext *context, gboolean may_block)
3181 context = g_main_context_default();
3183 LOCK_CONTEXT (context);
3184 retval = g_main_context_iterate (context, may_block, TRUE, G_THREAD_SELF);
3185 UNLOCK_CONTEXT (context);
3192 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used).
3193 * @is_running: set to %TRUE to indicate that the loop is running. This
3194 * is not very important since calling g_main_loop_run() will set this to
3197 * Creates a new #GMainLoop structure.
3199 * Return value: a new #GMainLoop.
3202 g_main_loop_new (GMainContext *context,
3203 gboolean is_running)
3208 context = g_main_context_default();
3210 g_main_context_ref (context);
3212 loop = g_new0 (GMainLoop, 1);
3213 loop->context = context;
3214 loop->is_running = is_running != FALSE;
3215 loop->ref_count = 1;
3222 * @loop: a #GMainLoop
3224 * Increases the reference count on a #GMainLoop object by one.
3226 * Return value: @loop
3229 g_main_loop_ref (GMainLoop *loop)
3231 g_return_val_if_fail (loop != NULL, NULL);
3232 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
3234 g_atomic_int_inc (&loop->ref_count);
3240 * g_main_loop_unref:
3241 * @loop: a #GMainLoop
3243 * Decreases the reference count on a #GMainLoop object by one. If
3244 * the result is zero, free the loop and free all associated memory.
3247 g_main_loop_unref (GMainLoop *loop)
3249 g_return_if_fail (loop != NULL);
3250 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3252 if (!g_atomic_int_dec_and_test (&loop->ref_count))
3255 g_main_context_unref (loop->context);
3261 * @loop: a #GMainLoop
3263 * Runs a main loop until g_main_loop_quit() is called on the loop.
3264 * If this is called for the thread of the loop's #GMainContext,
3265 * it will process events from the loop, otherwise it will
3269 g_main_loop_run (GMainLoop *loop)
3271 GThread *self = G_THREAD_SELF;
3273 g_return_if_fail (loop != NULL);
3274 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3276 if (!g_main_context_acquire (loop->context))
3278 gboolean got_ownership = FALSE;
3280 /* Another thread owns this context */
3281 LOCK_CONTEXT (loop->context);
3283 g_atomic_int_inc (&loop->ref_count);
3285 if (!loop->is_running)
3286 loop->is_running = TRUE;
3288 while (loop->is_running && !got_ownership)
3289 got_ownership = g_main_context_wait (loop->context,
3290 &loop->context->cond,
3291 &loop->context->mutex);
3293 if (!loop->is_running)
3295 UNLOCK_CONTEXT (loop->context);
3297 g_main_context_release (loop->context);
3298 g_main_loop_unref (loop);
3302 g_assert (got_ownership);
3305 LOCK_CONTEXT (loop->context);
3307 if (loop->context->in_check_or_prepare)
3309 g_warning ("g_main_loop_run(): called recursively from within a source's "
3310 "check() or prepare() member, iteration not possible.");
3314 g_atomic_int_inc (&loop->ref_count);
3315 loop->is_running = TRUE;
3316 while (loop->is_running)
3317 g_main_context_iterate (loop->context, TRUE, TRUE, self);
3319 UNLOCK_CONTEXT (loop->context);
3321 g_main_context_release (loop->context);
3323 g_main_loop_unref (loop);
3328 * @loop: a #GMainLoop
3330 * Stops a #GMainLoop from running. Any calls to g_main_loop_run()
3331 * for the loop will return.
3333 * Note that sources that have already been dispatched when
3334 * g_main_loop_quit() is called will still be executed.
3337 g_main_loop_quit (GMainLoop *loop)
3339 g_return_if_fail (loop != NULL);
3340 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3342 LOCK_CONTEXT (loop->context);
3343 loop->is_running = FALSE;
3344 g_wakeup_signal (loop->context->wakeup);
3346 g_cond_broadcast (&loop->context->cond);
3348 UNLOCK_CONTEXT (loop->context);
3352 * g_main_loop_is_running:
3353 * @loop: a #GMainLoop.
3355 * Checks to see if the main loop is currently being run via g_main_loop_run().
3357 * Return value: %TRUE if the mainloop is currently being run.
3360 g_main_loop_is_running (GMainLoop *loop)
3362 g_return_val_if_fail (loop != NULL, FALSE);
3363 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, FALSE);
3365 return loop->is_running;
3369 * g_main_loop_get_context:
3370 * @loop: a #GMainLoop.
3372 * Returns the #GMainContext of @loop.
3374 * Return value: (transfer none): the #GMainContext of @loop
3377 g_main_loop_get_context (GMainLoop *loop)
3379 g_return_val_if_fail (loop != NULL, NULL);
3380 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
3382 return loop->context;
3385 /* HOLDS: context's lock */
3387 g_main_context_poll (GMainContext *context,
3393 #ifdef G_MAIN_POLL_DEBUG
3399 GPollFunc poll_func;
3401 if (n_fds || timeout != 0)
3403 #ifdef G_MAIN_POLL_DEBUG
3404 if (_g_main_poll_debug)
3406 g_print ("polling context=%p n=%d timeout=%d\n",
3407 context, n_fds, timeout);
3408 poll_timer = g_timer_new ();
3412 LOCK_CONTEXT (context);
3414 poll_func = context->poll_func;
3416 UNLOCK_CONTEXT (context);
3417 if ((*poll_func) (fds, n_fds, timeout) < 0 && errno != EINTR)
3420 g_warning ("poll(2) failed due to: %s.",
3421 g_strerror (errno));
3423 /* If g_poll () returns -1, it has already called g_warning() */
3427 #ifdef G_MAIN_POLL_DEBUG
3428 if (_g_main_poll_debug)
3430 LOCK_CONTEXT (context);
3432 g_print ("g_main_poll(%d) timeout: %d - elapsed %12.10f seconds",
3435 g_timer_elapsed (poll_timer, NULL));
3436 g_timer_destroy (poll_timer);
3437 pollrec = context->poll_records;
3439 while (pollrec != NULL)
3444 if (fds[i].fd == pollrec->fd->fd &&
3445 pollrec->fd->events &&
3448 g_print (" [" G_POLLFD_FORMAT " :", fds[i].fd);
3449 if (fds[i].revents & G_IO_IN)
3451 if (fds[i].revents & G_IO_OUT)
3453 if (fds[i].revents & G_IO_PRI)
3455 if (fds[i].revents & G_IO_ERR)
3457 if (fds[i].revents & G_IO_HUP)
3459 if (fds[i].revents & G_IO_NVAL)
3465 pollrec = pollrec->next;
3469 UNLOCK_CONTEXT (context);
3472 } /* if (n_fds || timeout != 0) */
3476 * g_main_context_add_poll:
3477 * @context: a #GMainContext (or %NULL for the default context)
3478 * @fd: a #GPollFD structure holding information about a file
3479 * descriptor to watch.
3480 * @priority: the priority for this file descriptor which should be
3481 * the same as the priority used for g_source_attach() to ensure that the
3482 * file descriptor is polled whenever the results may be needed.
3484 * Adds a file descriptor to the set of file descriptors polled for
3485 * this context. This will very seldom be used directly. Instead
3486 * a typical event source will use g_source_add_poll() instead.
3489 g_main_context_add_poll (GMainContext *context,
3494 context = g_main_context_default ();
3496 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3497 g_return_if_fail (fd);
3499 LOCK_CONTEXT (context);
3500 g_main_context_add_poll_unlocked (context, priority, fd);
3501 UNLOCK_CONTEXT (context);
3504 /* HOLDS: main_loop_lock */
3506 g_main_context_add_poll_unlocked (GMainContext *context,
3510 GPollRec *prevrec, *nextrec;
3511 GPollRec *newrec = g_slice_new (GPollRec);
3513 /* This file descriptor may be checked before we ever poll */
3516 newrec->priority = priority;
3518 prevrec = context->poll_records_tail;
3520 while (prevrec && priority < prevrec->priority)
3523 prevrec = prevrec->prev;
3527 prevrec->next = newrec;
3529 context->poll_records = newrec;
3531 newrec->prev = prevrec;
3532 newrec->next = nextrec;
3535 nextrec->prev = newrec;
3537 context->poll_records_tail = newrec;
3539 context->n_poll_records++;
3541 context->poll_changed = TRUE;
3543 /* Now wake up the main loop if it is waiting in the poll() */
3544 g_wakeup_signal (context->wakeup);
3548 * g_main_context_remove_poll:
3549 * @context:a #GMainContext
3550 * @fd: a #GPollFD descriptor previously added with g_main_context_add_poll()
3552 * Removes file descriptor from the set of file descriptors to be
3553 * polled for a particular context.
3556 g_main_context_remove_poll (GMainContext *context,
3560 context = g_main_context_default ();
3562 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3563 g_return_if_fail (fd);
3565 LOCK_CONTEXT (context);
3566 g_main_context_remove_poll_unlocked (context, fd);
3567 UNLOCK_CONTEXT (context);
3571 g_main_context_remove_poll_unlocked (GMainContext *context,
3574 GPollRec *pollrec, *prevrec, *nextrec;
3577 pollrec = context->poll_records;
3581 nextrec = pollrec->next;
3582 if (pollrec->fd == fd)
3584 if (prevrec != NULL)
3585 prevrec->next = nextrec;
3587 context->poll_records = nextrec;
3589 if (nextrec != NULL)
3590 nextrec->prev = prevrec;
3592 context->poll_records_tail = prevrec;
3594 g_slice_free (GPollRec, pollrec);
3596 context->n_poll_records--;
3603 context->poll_changed = TRUE;
3605 /* Now wake up the main loop if it is waiting in the poll() */
3606 g_wakeup_signal (context->wakeup);
3610 * g_source_get_current_time:
3611 * @source: a #GSource
3612 * @timeval: #GTimeVal structure in which to store current time.
3614 * This function ignores @source and is otherwise the same as
3615 * g_get_current_time().
3617 * Deprecated: 2.28: use g_source_get_time() instead
3620 g_source_get_current_time (GSource *source,
3623 g_get_current_time (timeval);
3627 * g_source_get_time:
3628 * @source: a #GSource
3630 * Gets the time to be used when checking this source. The advantage of
3631 * calling this function over calling g_get_monotonic_time() directly is
3632 * that when checking multiple sources, GLib can cache a single value
3633 * instead of having to repeatedly get the system monotonic time.
3635 * The time here is the system monotonic time, if available, or some
3636 * other reasonable alternative otherwise. See g_get_monotonic_time().
3638 * Returns: the monotonic time in microseconds
3643 g_source_get_time (GSource *source)
3645 GMainContext *context;
3648 g_return_val_if_fail (source->context != NULL, 0);
3650 context = source->context;
3652 LOCK_CONTEXT (context);
3654 if (!context->time_is_fresh)
3656 context->time = g_get_monotonic_time ();
3657 context->time_is_fresh = TRUE;
3660 result = context->time;
3662 UNLOCK_CONTEXT (context);
3668 * g_main_context_set_poll_func:
3669 * @context: a #GMainContext
3670 * @func: the function to call to poll all file descriptors
3672 * Sets the function to use to handle polling of file descriptors. It
3673 * will be used instead of the poll() system call
3674 * (or GLib's replacement function, which is used where
3675 * poll() isn't available).
3677 * This function could possibly be used to integrate the GLib event
3678 * loop with an external event loop.
3681 g_main_context_set_poll_func (GMainContext *context,
3685 context = g_main_context_default ();
3687 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3689 LOCK_CONTEXT (context);
3692 context->poll_func = func;
3694 context->poll_func = g_poll;
3696 UNLOCK_CONTEXT (context);
3700 * g_main_context_get_poll_func:
3701 * @context: a #GMainContext
3703 * Gets the poll function set by g_main_context_set_poll_func().
3705 * Return value: the poll function
3708 g_main_context_get_poll_func (GMainContext *context)
3713 context = g_main_context_default ();
3715 g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL);
3717 LOCK_CONTEXT (context);
3718 result = context->poll_func;
3719 UNLOCK_CONTEXT (context);
3725 * g_main_context_wakeup:
3726 * @context: a #GMainContext
3728 * If @context is currently waiting in a poll(), interrupt
3729 * the poll(), and continue the iteration process.
3732 g_main_context_wakeup (GMainContext *context)
3735 context = g_main_context_default ();
3737 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3739 g_wakeup_signal (context->wakeup);
3743 * g_main_context_is_owner:
3744 * @context: a #GMainContext
3746 * Determines whether this thread holds the (recursive)
3747 * ownership of this #GMainContext. This is useful to
3748 * know before waiting on another thread that may be
3749 * blocking to get ownership of @context.
3751 * Returns: %TRUE if current thread is owner of @context.
3756 g_main_context_is_owner (GMainContext *context)
3761 context = g_main_context_default ();
3763 LOCK_CONTEXT (context);
3764 is_owner = context->owner == G_THREAD_SELF;
3765 UNLOCK_CONTEXT (context);
3773 g_timeout_set_expiration (GTimeoutSource *timeout_source,
3774 gint64 current_time)
3776 timeout_source->expiration = current_time +
3777 (guint64) timeout_source->interval * 1000;
3779 if (timeout_source->seconds)
3782 static gint timer_perturb = -1;
3784 if (timer_perturb == -1)
3787 * we want a per machine/session unique 'random' value; try the dbus
3788 * address first, that has a UUID in it. If there is no dbus, use the
3789 * hostname for hashing.
3791 const char *session_bus_address = g_getenv ("DBUS_SESSION_BUS_ADDRESS");
3792 if (!session_bus_address)
3793 session_bus_address = g_getenv ("HOSTNAME");
3794 if (session_bus_address)
3795 timer_perturb = ABS ((gint) g_str_hash (session_bus_address)) % 1000000;
3800 /* We want the microseconds part of the timeout to land on the
3801 * 'timer_perturb' mark, but we need to make sure we don't try to
3802 * set the timeout in the past. We do this by ensuring that we
3803 * always only *increase* the expiration time by adding a full
3804 * second in the case that the microsecond portion decreases.
3806 timeout_source->expiration -= timer_perturb;
3808 remainder = timeout_source->expiration % 1000000;
3809 if (remainder >= 1000000/4)
3810 timeout_source->expiration += 1000000;
3812 timeout_source->expiration -= remainder;
3813 timeout_source->expiration += timer_perturb;
3818 g_timeout_prepare (GSource *source,
3821 GTimeoutSource *timeout_source = (GTimeoutSource *) source;
3822 gint64 now = g_source_get_time (source);
3824 if (now < timeout_source->expiration)
3826 /* Round up to ensure that we don't try again too early */
3827 *timeout = (timeout_source->expiration - now + 999) / 1000;
3836 g_timeout_check (GSource *source)
3838 GTimeoutSource *timeout_source = (GTimeoutSource *) source;
3839 gint64 now = g_source_get_time (source);
3841 return timeout_source->expiration <= now;
3845 g_timeout_dispatch (GSource *source,
3846 GSourceFunc callback,
3849 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3854 g_warning ("Timeout source dispatched without callback\n"
3855 "You must call g_source_set_callback().");
3859 again = callback (user_data);
3862 g_timeout_set_expiration (timeout_source, g_source_get_time (source));
3868 * g_timeout_source_new:
3869 * @interval: the timeout interval in milliseconds.
3871 * Creates a new timeout source.
3873 * The source will not initially be associated with any #GMainContext
3874 * and must be added to one with g_source_attach() before it will be
3877 * The interval given is in terms of monotonic time, not wall clock
3878 * time. See g_get_monotonic_time().
3880 * Return value: the newly-created timeout source
3883 g_timeout_source_new (guint interval)
3885 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
3886 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3888 timeout_source->interval = interval;
3889 g_timeout_set_expiration (timeout_source, g_get_monotonic_time ());
3895 * g_timeout_source_new_seconds:
3896 * @interval: the timeout interval in seconds
3898 * Creates a new timeout source.
3900 * The source will not initially be associated with any #GMainContext
3901 * and must be added to one with g_source_attach() before it will be
3904 * The scheduling granularity/accuracy of this timeout source will be
3907 * The interval given in terms of monotonic time, not wall clock time.
3908 * See g_get_monotonic_time().
3910 * Return value: the newly-created timeout source
3915 g_timeout_source_new_seconds (guint interval)
3917 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
3918 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3920 timeout_source->interval = 1000 * interval;
3921 timeout_source->seconds = TRUE;
3923 g_timeout_set_expiration (timeout_source, g_get_monotonic_time ());
3930 * g_timeout_add_full:
3931 * @priority: the priority of the timeout source. Typically this will be in
3932 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
3933 * @interval: the time between calls to the function, in milliseconds
3934 * (1/1000ths of a second)
3935 * @function: function to call
3936 * @data: data to pass to @function
3937 * @notify: function to call when the timeout is removed, or %NULL
3939 * Sets a function to be called at regular intervals, with the given
3940 * priority. The function is called repeatedly until it returns
3941 * %FALSE, at which point the timeout is automatically destroyed and
3942 * the function will not be called again. The @notify function is
3943 * called when the timeout is destroyed. The first call to the
3944 * function will be at the end of the first @interval.
3946 * Note that timeout functions may be delayed, due to the processing of other
3947 * event sources. Thus they should not be relied on for precise timing.
3948 * After each call to the timeout function, the time of the next
3949 * timeout is recalculated based on the current time and the given interval
3950 * (it does not try to 'catch up' time lost in delays).
3952 * This internally creates a main loop source using g_timeout_source_new()
3953 * and attaches it to the main loop context using g_source_attach(). You can
3954 * do these steps manually if you need greater control.
3956 * The interval given in terms of monotonic time, not wall clock time.
3957 * See g_get_monotonic_time().
3959 * Return value: the ID (greater than 0) of the event source.
3960 * Rename to: g_timeout_add
3963 g_timeout_add_full (gint priority,
3965 GSourceFunc function,
3967 GDestroyNotify notify)
3972 g_return_val_if_fail (function != NULL, 0);
3974 source = g_timeout_source_new (interval);
3976 if (priority != G_PRIORITY_DEFAULT)
3977 g_source_set_priority (source, priority);
3979 g_source_set_callback (source, function, data, notify);
3980 id = g_source_attach (source, NULL);
3981 g_source_unref (source);
3988 * @interval: the time between calls to the function, in milliseconds
3989 * (1/1000ths of a second)
3990 * @function: function to call
3991 * @data: data to pass to @function
3993 * Sets a function to be called at regular intervals, with the default
3994 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly
3995 * until it returns %FALSE, at which point the timeout is automatically
3996 * destroyed and the function will not be called again. The first call
3997 * to the function will be at the end of the first @interval.
3999 * Note that timeout functions may be delayed, due to the processing of other
4000 * event sources. Thus they should not be relied on for precise timing.
4001 * After each call to the timeout function, the time of the next
4002 * timeout is recalculated based on the current time and the given interval
4003 * (it does not try to 'catch up' time lost in delays).
4005 * If you want to have a timer in the "seconds" range and do not care
4006 * about the exact time of the first call of the timer, use the
4007 * g_timeout_add_seconds() function; this function allows for more
4008 * optimizations and more efficient system power usage.
4010 * This internally creates a main loop source using g_timeout_source_new()
4011 * and attaches it to the main loop context using g_source_attach(). You can
4012 * do these steps manually if you need greater control.
4014 * The interval given is in terms of monotonic time, not wall clock
4015 * time. See g_get_monotonic_time().
4017 * Return value: the ID (greater than 0) of the event source.
4020 g_timeout_add (guint32 interval,
4021 GSourceFunc function,
4024 return g_timeout_add_full (G_PRIORITY_DEFAULT,
4025 interval, function, data, NULL);
4029 * g_timeout_add_seconds_full:
4030 * @priority: the priority of the timeout source. Typically this will be in
4031 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
4032 * @interval: the time between calls to the function, in seconds
4033 * @function: function to call
4034 * @data: data to pass to @function
4035 * @notify: function to call when the timeout is removed, or %NULL
4037 * Sets a function to be called at regular intervals, with @priority.
4038 * The function is called repeatedly until it returns %FALSE, at which
4039 * point the timeout is automatically destroyed and the function will
4040 * not be called again.
4042 * Unlike g_timeout_add(), this function operates at whole second granularity.
4043 * The initial starting point of the timer is determined by the implementation
4044 * and the implementation is expected to group multiple timers together so that
4045 * they fire all at the same time.
4046 * To allow this grouping, the @interval to the first timer is rounded
4047 * and can deviate up to one second from the specified interval.
4048 * Subsequent timer iterations will generally run at the specified interval.
4050 * Note that timeout functions may be delayed, due to the processing of other
4051 * event sources. Thus they should not be relied on for precise timing.
4052 * After each call to the timeout function, the time of the next
4053 * timeout is recalculated based on the current time and the given @interval
4055 * If you want timing more precise than whole seconds, use g_timeout_add()
4058 * The grouping of timers to fire at the same time results in a more power
4059 * and CPU efficient behavior so if your timer is in multiples of seconds
4060 * and you don't require the first timer exactly one second from now, the
4061 * use of g_timeout_add_seconds() is preferred over g_timeout_add().
4063 * This internally creates a main loop source using
4064 * g_timeout_source_new_seconds() and attaches it to the main loop context
4065 * using g_source_attach(). You can do these steps manually if you need
4068 * The interval given is in terms of monotonic time, not wall clock
4069 * time. See g_get_monotonic_time().
4071 * Return value: the ID (greater than 0) of the event source.
4073 * Rename to: g_timeout_add_seconds
4077 g_timeout_add_seconds_full (gint priority,
4079 GSourceFunc function,
4081 GDestroyNotify notify)
4086 g_return_val_if_fail (function != NULL, 0);
4088 source = g_timeout_source_new_seconds (interval);
4090 if (priority != G_PRIORITY_DEFAULT)
4091 g_source_set_priority (source, priority);
4093 g_source_set_callback (source, function, data, notify);
4094 id = g_source_attach (source, NULL);
4095 g_source_unref (source);
4101 * g_timeout_add_seconds:
4102 * @interval: the time between calls to the function, in seconds
4103 * @function: function to call
4104 * @data: data to pass to @function
4106 * Sets a function to be called at regular intervals with the default
4107 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly until
4108 * it returns %FALSE, at which point the timeout is automatically destroyed
4109 * and the function will not be called again.
4111 * This internally creates a main loop source using
4112 * g_timeout_source_new_seconds() and attaches it to the main loop context
4113 * using g_source_attach(). You can do these steps manually if you need
4114 * greater control. Also see g_timeout_add_seconds_full().
4116 * Note that the first call of the timer may not be precise for timeouts
4117 * of one second. If you need finer precision and have such a timeout,
4118 * you may want to use g_timeout_add() instead.
4120 * The interval given is in terms of monotonic time, not wall clock
4121 * time. See g_get_monotonic_time().
4123 * Return value: the ID (greater than 0) of the event source.
4128 g_timeout_add_seconds (guint interval,
4129 GSourceFunc function,
4132 g_return_val_if_fail (function != NULL, 0);
4134 return g_timeout_add_seconds_full (G_PRIORITY_DEFAULT, interval, function, data, NULL);
4137 /* Child watch functions */
4142 g_child_watch_prepare (GSource *source,
4150 g_child_watch_check (GSource *source)
4152 GChildWatchSource *child_watch_source;
4153 gboolean child_exited;
4155 child_watch_source = (GChildWatchSource *) source;
4157 child_exited = child_watch_source->poll.revents & G_IO_IN;
4164 * Note: We do _not_ check for the special value of STILL_ACTIVE
4165 * since we know that the process has exited and doing so runs into
4166 * problems if the child process "happens to return STILL_ACTIVE(259)"
4167 * as Microsoft's Platform SDK puts it.
4169 if (!GetExitCodeProcess (child_watch_source->pid, &child_status))
4171 gchar *emsg = g_win32_error_message (GetLastError ());
4172 g_warning (G_STRLOC ": GetExitCodeProcess() failed: %s", emsg);
4175 child_watch_source->child_status = -1;
4178 child_watch_source->child_status = child_status;
4181 return child_exited;
4185 g_child_watch_finalize (GSource *source)
4189 #else /* G_OS_WIN32 */
4192 wake_source (GSource *source)
4194 GMainContext *context;
4196 /* This should be thread-safe:
4198 * - if the source is currently being added to a context, that
4199 * context will be woken up anyway
4201 * - if the source is currently being destroyed, we simply need not
4204 * - the memory for the source will remain valid until after the
4205 * source finalize function was called (which would remove the
4206 * source from the global list which we are currently holding the
4209 * - the GMainContext will either be NULL or point to a live
4212 * - the GMainContext will remain valid since we hold the
4213 * main_context_list lock
4215 * Since we are holding a lot of locks here, don't try to enter any
4216 * more GMainContext functions for fear of dealock -- just hit the
4217 * GWakeup and run. Even if that's safe now, it could easily become
4218 * unsafe with some very minor changes in the future, and signal
4219 * handling is not the most well-tested codepath.
4221 G_LOCK(main_context_list);
4222 context = source->context;
4224 g_wakeup_signal (context->wakeup);
4225 G_UNLOCK(main_context_list);
4229 dispatch_unix_signals (void)
4233 /* clear this first incase another one arrives while we're processing */
4234 any_unix_signal_pending = FALSE;
4236 G_LOCK(unix_signal_lock);
4238 /* handle GChildWatchSource instances */
4239 if (unix_signal_pending[SIGCHLD])
4241 unix_signal_pending[SIGCHLD] = FALSE;
4243 /* The only way we can do this is to scan all of the children.
4245 * The docs promise that we will not reap children that we are not
4246 * explicitly watching, so that ties our hands from calling
4247 * waitpid(-1). We also can't use siginfo's si_pid field since if
4248 * multiple SIGCHLD arrive at the same time, one of them can be
4249 * dropped (since a given UNIX signal can only be pending once).
4251 for (node = unix_child_watches; node; node = node->next)
4253 GChildWatchSource *source = node->data;
4255 if (!source->child_exited)
4257 if (waitpid (source->pid, &source->child_status, WNOHANG) > 0)
4259 source->child_exited = TRUE;
4261 wake_source ((GSource *) source);
4267 /* handle GUnixSignalWatchSource instances */
4268 for (node = unix_signal_watches; node; node = node->next)
4270 GUnixSignalWatchSource *source = node->data;
4272 if (!source->pending)
4274 if (unix_signal_pending[source->signum])
4276 unix_signal_pending[source->signum] = FALSE;
4277 source->pending = TRUE;
4279 wake_source ((GSource *) source);
4284 G_UNLOCK(unix_signal_lock);
4288 g_child_watch_prepare (GSource *source,
4291 GChildWatchSource *child_watch_source;
4293 child_watch_source = (GChildWatchSource *) source;
4295 return child_watch_source->child_exited;
4299 g_child_watch_check (GSource *source)
4301 GChildWatchSource *child_watch_source;
4303 child_watch_source = (GChildWatchSource *) source;
4305 return child_watch_source->child_exited;
4309 g_unix_signal_watch_prepare (GSource *source,
4312 GUnixSignalWatchSource *unix_signal_source;
4314 unix_signal_source = (GUnixSignalWatchSource *) source;
4316 return unix_signal_source->pending;
4320 g_unix_signal_watch_check (GSource *source)
4322 GUnixSignalWatchSource *unix_signal_source;
4324 unix_signal_source = (GUnixSignalWatchSource *) source;
4326 return unix_signal_source->pending;
4330 g_unix_signal_watch_dispatch (GSource *source,
4331 GSourceFunc callback,
4334 GUnixSignalWatchSource *unix_signal_source;
4336 unix_signal_source = (GUnixSignalWatchSource *) source;
4340 g_warning ("Unix signal source dispatched without callback\n"
4341 "You must call g_source_set_callback().");
4345 (callback) (user_data);
4347 unix_signal_source->pending = FALSE;
4353 ensure_unix_signal_handler_installed_unlocked (int signum)
4355 static sigset_t installed_signal_mask;
4356 static gboolean initialized;
4357 struct sigaction action;
4361 sigemptyset (&installed_signal_mask);
4362 g_get_worker_context ();
4366 if (sigismember (&installed_signal_mask, signum))
4369 sigaddset (&installed_signal_mask, signum);
4371 action.sa_handler = g_unix_signal_handler;
4372 sigemptyset (&action.sa_mask);
4373 action.sa_flags = SA_RESTART | SA_NOCLDSTOP;
4374 sigaction (signum, &action, NULL);
4378 _g_main_create_unix_signal_watch (int signum)
4381 GUnixSignalWatchSource *unix_signal_source;
4383 source = g_source_new (&g_unix_signal_funcs, sizeof (GUnixSignalWatchSource));
4384 unix_signal_source = (GUnixSignalWatchSource *) source;
4386 unix_signal_source->signum = signum;
4387 unix_signal_source->pending = FALSE;
4389 G_LOCK (unix_signal_lock);
4390 ensure_unix_signal_handler_installed_unlocked (signum);
4391 unix_signal_watches = g_slist_prepend (unix_signal_watches, unix_signal_source);
4392 if (unix_signal_pending[signum])
4393 unix_signal_source->pending = TRUE;
4394 unix_signal_pending[signum] = FALSE;
4395 G_UNLOCK (unix_signal_lock);
4401 g_unix_signal_watch_finalize (GSource *source)
4403 G_LOCK (unix_signal_lock);
4404 unix_signal_watches = g_slist_remove (unix_signal_watches, source);
4405 G_UNLOCK (unix_signal_lock);
4409 g_child_watch_finalize (GSource *source)
4411 G_LOCK (unix_signal_lock);
4412 unix_child_watches = g_slist_remove (unix_child_watches, source);
4413 G_UNLOCK (unix_signal_lock);
4416 #endif /* G_OS_WIN32 */
4419 g_child_watch_dispatch (GSource *source,
4420 GSourceFunc callback,
4423 GChildWatchSource *child_watch_source;
4424 GChildWatchFunc child_watch_callback = (GChildWatchFunc) callback;
4426 child_watch_source = (GChildWatchSource *) source;
4430 g_warning ("Child watch source dispatched without callback\n"
4431 "You must call g_source_set_callback().");
4435 (child_watch_callback) (child_watch_source->pid, child_watch_source->child_status, user_data);
4437 /* We never keep a child watch source around as the child is gone */
4444 g_unix_signal_handler (int signum)
4446 unix_signal_pending[signum] = TRUE;
4447 any_unix_signal_pending = TRUE;
4449 g_wakeup_signal (glib_worker_context->wakeup);
4452 #endif /* !G_OS_WIN32 */
4455 * g_child_watch_source_new:
4456 * @pid: process to watch. On POSIX the pid of a child process. On
4457 * Windows a handle for a process (which doesn't have to be a child).
4459 * Creates a new child_watch source.
4461 * The source will not initially be associated with any #GMainContext
4462 * and must be added to one with g_source_attach() before it will be
4465 * Note that child watch sources can only be used in conjunction with
4466 * <literal>g_spawn...</literal> when the %G_SPAWN_DO_NOT_REAP_CHILD
4469 * Note that on platforms where #GPid must be explicitly closed
4470 * (see g_spawn_close_pid()) @pid must not be closed while the
4471 * source is still active. Typically, you will want to call
4472 * g_spawn_close_pid() in the callback function for the source.
4474 * Note further that using g_child_watch_source_new() is not
4475 * compatible with calling <literal>waitpid(-1)</literal> in
4476 * the application. Calling waitpid() for individual pids will
4479 * Return value: the newly-created child watch source
4484 g_child_watch_source_new (GPid pid)
4486 GSource *source = g_source_new (&g_child_watch_funcs, sizeof (GChildWatchSource));
4487 GChildWatchSource *child_watch_source = (GChildWatchSource *)source;
4489 child_watch_source->pid = pid;
4492 child_watch_source->poll.fd = (gintptr) pid;
4493 child_watch_source->poll.events = G_IO_IN;
4495 g_source_add_poll (source, &child_watch_source->poll);
4496 #else /* G_OS_WIN32 */
4497 G_LOCK (unix_signal_lock);
4498 ensure_unix_signal_handler_installed_unlocked (SIGCHLD);
4499 unix_child_watches = g_slist_prepend (unix_child_watches, child_watch_source);
4500 if (waitpid (pid, &child_watch_source->child_status, WNOHANG) > 0)
4501 child_watch_source->child_exited = TRUE;
4502 G_UNLOCK (unix_signal_lock);
4503 #endif /* G_OS_WIN32 */
4509 * g_child_watch_add_full:
4510 * @priority: the priority of the idle source. Typically this will be in the
4511 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
4512 * @pid: process to watch. On POSIX the pid of a child process. On
4513 * Windows a handle for a process (which doesn't have to be a child).
4514 * @function: function to call
4515 * @data: data to pass to @function
4516 * @notify: function to call when the idle is removed, or %NULL
4518 * Sets a function to be called when the child indicated by @pid
4519 * exits, at the priority @priority.
4521 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
4522 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
4523 * the spawn function for the child watching to work.
4525 * Note that on platforms where #GPid must be explicitly closed
4526 * (see g_spawn_close_pid()) @pid must not be closed while the
4527 * source is still active. Typically, you will want to call
4528 * g_spawn_close_pid() in the callback function for the source.
4530 * GLib supports only a single callback per process id.
4532 * This internally creates a main loop source using
4533 * g_child_watch_source_new() and attaches it to the main loop context
4534 * using g_source_attach(). You can do these steps manually if you
4535 * need greater control.
4537 * Return value: the ID (greater than 0) of the event source.
4539 * Rename to: g_child_watch_add
4543 g_child_watch_add_full (gint priority,
4545 GChildWatchFunc function,
4547 GDestroyNotify notify)
4552 g_return_val_if_fail (function != NULL, 0);
4554 source = g_child_watch_source_new (pid);
4556 if (priority != G_PRIORITY_DEFAULT)
4557 g_source_set_priority (source, priority);
4559 g_source_set_callback (source, (GSourceFunc) function, data, notify);
4560 id = g_source_attach (source, NULL);
4561 g_source_unref (source);
4567 * g_child_watch_add:
4568 * @pid: process id to watch. On POSIX the pid of a child process. On
4569 * Windows a handle for a process (which doesn't have to be a child).
4570 * @function: function to call
4571 * @data: data to pass to @function
4573 * Sets a function to be called when the child indicated by @pid
4574 * exits, at a default priority, #G_PRIORITY_DEFAULT.
4576 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
4577 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
4578 * the spawn function for the child watching to work.
4580 * Note that on platforms where #GPid must be explicitly closed
4581 * (see g_spawn_close_pid()) @pid must not be closed while the
4582 * source is still active. Typically, you will want to call
4583 * g_spawn_close_pid() in the callback function for the source.
4585 * GLib supports only a single callback per process id.
4587 * This internally creates a main loop source using
4588 * g_child_watch_source_new() and attaches it to the main loop context
4589 * using g_source_attach(). You can do these steps manually if you
4590 * need greater control.
4592 * Return value: the ID (greater than 0) of the event source.
4597 g_child_watch_add (GPid pid,
4598 GChildWatchFunc function,
4601 return g_child_watch_add_full (G_PRIORITY_DEFAULT, pid, function, data, NULL);
4605 /* Idle functions */
4608 g_idle_prepare (GSource *source,
4617 g_idle_check (GSource *source)
4623 g_idle_dispatch (GSource *source,
4624 GSourceFunc callback,
4629 g_warning ("Idle source dispatched without callback\n"
4630 "You must call g_source_set_callback().");
4634 return callback (user_data);
4638 * g_idle_source_new:
4640 * Creates a new idle source.
4642 * The source will not initially be associated with any #GMainContext
4643 * and must be added to one with g_source_attach() before it will be
4644 * executed. Note that the default priority for idle sources is
4645 * %G_PRIORITY_DEFAULT_IDLE, as compared to other sources which
4646 * have a default priority of %G_PRIORITY_DEFAULT.
4648 * Return value: the newly-created idle source
4651 g_idle_source_new (void)
4655 source = g_source_new (&g_idle_funcs, sizeof (GSource));
4656 g_source_set_priority (source, G_PRIORITY_DEFAULT_IDLE);
4663 * @priority: the priority of the idle source. Typically this will be in the
4664 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
4665 * @function: function to call
4666 * @data: data to pass to @function
4667 * @notify: function to call when the idle is removed, or %NULL
4669 * Adds a function to be called whenever there are no higher priority
4670 * events pending. If the function returns %FALSE it is automatically
4671 * removed from the list of event sources and will not be called again.
4673 * This internally creates a main loop source using g_idle_source_new()
4674 * and attaches it to the main loop context using g_source_attach().
4675 * You can do these steps manually if you need greater control.
4677 * Return value: the ID (greater than 0) of the event source.
4678 * Rename to: g_idle_add
4681 g_idle_add_full (gint priority,
4682 GSourceFunc function,
4684 GDestroyNotify notify)
4689 g_return_val_if_fail (function != NULL, 0);
4691 source = g_idle_source_new ();
4693 if (priority != G_PRIORITY_DEFAULT_IDLE)
4694 g_source_set_priority (source, priority);
4696 g_source_set_callback (source, function, data, notify);
4697 id = g_source_attach (source, NULL);
4698 g_source_unref (source);
4705 * @function: function to call
4706 * @data: data to pass to @function.
4708 * Adds a function to be called whenever there are no higher priority
4709 * events pending to the default main loop. The function is given the
4710 * default idle priority, #G_PRIORITY_DEFAULT_IDLE. If the function
4711 * returns %FALSE it is automatically removed from the list of event
4712 * sources and will not be called again.
4714 * This internally creates a main loop source using g_idle_source_new()
4715 * and attaches it to the main loop context using g_source_attach().
4716 * You can do these steps manually if you need greater control.
4718 * Return value: the ID (greater than 0) of the event source.
4721 g_idle_add (GSourceFunc function,
4724 return g_idle_add_full (G_PRIORITY_DEFAULT_IDLE, function, data, NULL);
4728 * g_idle_remove_by_data:
4729 * @data: the data for the idle source's callback.
4731 * Removes the idle function with the given data.
4733 * Return value: %TRUE if an idle source was found and removed.
4736 g_idle_remove_by_data (gpointer data)
4738 return g_source_remove_by_funcs_user_data (&g_idle_funcs, data);
4742 * g_main_context_invoke:
4743 * @context: (allow-none): a #GMainContext, or %NULL
4744 * @function: function to call
4745 * @data: data to pass to @function
4747 * Invokes a function in such a way that @context is owned during the
4748 * invocation of @function.
4750 * If @context is %NULL then the global default main context — as
4751 * returned by g_main_context_default() — is used.
4753 * If @context is owned by the current thread, @function is called
4754 * directly. Otherwise, if @context is the thread-default main context
4755 * of the current thread and g_main_context_acquire() succeeds, then
4756 * @function is called and g_main_context_release() is called
4759 * In any other case, an idle source is created to call @function and
4760 * that source is attached to @context (presumably to be run in another
4761 * thread). The idle source is attached with #G_PRIORITY_DEFAULT
4762 * priority. If you want a different priority, use
4763 * g_main_context_invoke_full().
4765 * Note that, as with normal idle functions, @function should probably
4766 * return %FALSE. If it returns %TRUE, it will be continuously run in a
4767 * loop (and may prevent this call from returning).
4772 g_main_context_invoke (GMainContext *context,
4773 GSourceFunc function,
4776 g_main_context_invoke_full (context,
4778 function, data, NULL);
4782 * g_main_context_invoke_full:
4783 * @context: (allow-none): a #GMainContext, or %NULL
4784 * @priority: the priority at which to run @function
4785 * @function: function to call
4786 * @data: data to pass to @function
4787 * @notify: a function to call when @data is no longer in use, or %NULL.
4789 * Invokes a function in such a way that @context is owned during the
4790 * invocation of @function.
4792 * This function is the same as g_main_context_invoke() except that it
4793 * lets you specify the priority incase @function ends up being
4794 * scheduled as an idle and also lets you give a #GDestroyNotify for @data.
4796 * @notify should not assume that it is called from any particular
4797 * thread or with any particular context acquired.
4802 g_main_context_invoke_full (GMainContext *context,
4804 GSourceFunc function,
4806 GDestroyNotify notify)
4808 g_return_if_fail (function != NULL);
4811 context = g_main_context_default ();
4813 if (g_main_context_is_owner (context))
4815 while (function (data));
4822 GMainContext *thread_default;
4824 thread_default = g_main_context_get_thread_default ();
4826 if (!thread_default)
4827 thread_default = g_main_context_default ();
4829 if (thread_default == context && g_main_context_acquire (context))
4831 while (function (data));
4833 g_main_context_release (context);
4842 source = g_idle_source_new ();
4843 g_source_set_priority (source, priority);
4844 g_source_set_callback (source, function, data, notify);
4845 g_source_attach (source, context);
4846 g_source_unref (source);
4852 glib_worker_main (gpointer data)
4856 g_main_context_iteration (glib_worker_context, TRUE);
4859 if (any_unix_signal_pending)
4860 dispatch_unix_signals ();
4864 return NULL; /* worst GCC warning message ever... */
4868 g_get_worker_context (void)
4870 static gsize initialised;
4872 if (g_once_init_enter (&initialised))
4874 /* mask all signals in the worker thread */
4880 pthread_sigmask (SIG_SETMASK, &all, &prev_mask);
4882 glib_worker_context = g_main_context_new ();
4883 g_thread_new ("gmain", glib_worker_main, NULL);
4885 pthread_sigmask (SIG_SETMASK, &prev_mask, NULL);
4887 g_once_init_leave (&initialised, TRUE);
4890 return glib_worker_context;