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, see <http://www.gnu.org/licenses/>.
22 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
23 * file for a list of people on the GLib Team. See the ChangeLog
24 * files for a list of changes. These files are distributed with
25 * GLib at ftp://ftp.gtk.org/pub/gtk/.
33 #include "glibconfig.h"
35 /* Uncomment the next line (and the corresponding line in gpoll.c) to
36 * enable debugging printouts if the environment variable
37 * G_MAIN_POLL_DEBUG is set to some value.
39 /* #define G_MAIN_POLL_DEBUG */
42 /* Always enable debugging printout on Windows, as it is more often
45 #define G_MAIN_POLL_DEBUG
49 #include "glib-unix.h"
52 #include <sys/eventfd.h>
57 #include <sys/types.h>
60 #ifdef HAVE_SYS_TIME_H
62 #endif /* HAVE_SYS_TIME_H */
65 #endif /* G_OS_UNIX */
72 #endif /* G_OS_WIN32 */
74 #include "glib_trace.h"
79 #include "giochannel.h"
83 #include "gstrfuncs.h"
84 #include "gtestutils.h"
90 #ifdef G_MAIN_POLL_DEBUG
95 #include "gmain-internal.h"
96 #include "glib-init.h"
97 #include "glib-private.h"
101 * @title: The Main Event Loop
102 * @short_description: manages all available sources of events
104 * The main event loop manages all the available sources of events for
105 * GLib and GTK+ applications. These events can come from any number of
106 * different types of sources such as file descriptors (plain files,
107 * pipes or sockets) and timeouts. New types of event sources can also
108 * be added using g_source_attach().
110 * To allow multiple independent sets of sources to be handled in
111 * different threads, each source is associated with a #GMainContext.
112 * A GMainContext can only be running in a single thread, but
113 * sources can be added to it and removed from it from other threads.
115 * Each event source is assigned a priority. The default priority,
116 * #G_PRIORITY_DEFAULT, is 0. Values less than 0 denote higher priorities.
117 * Values greater than 0 denote lower priorities. Events from high priority
118 * sources are always processed before events from lower priority sources.
120 * Idle functions can also be added, and assigned a priority. These will
121 * be run whenever no events with a higher priority are ready to be processed.
123 * The #GMainLoop data type represents a main event loop. A GMainLoop is
124 * created with g_main_loop_new(). After adding the initial event sources,
125 * g_main_loop_run() is called. This continuously checks for new events from
126 * each of the event sources and dispatches them. Finally, the processing of
127 * an event from one of the sources leads to a call to g_main_loop_quit() to
128 * exit the main loop, and g_main_loop_run() returns.
130 * It is possible to create new instances of #GMainLoop recursively.
131 * This is often used in GTK+ applications when showing modal dialog
132 * boxes. Note that event sources are associated with a particular
133 * #GMainContext, and will be checked and dispatched for all main
134 * loops associated with that GMainContext.
136 * GTK+ contains wrappers of some of these functions, e.g. gtk_main(),
137 * gtk_main_quit() and gtk_events_pending().
139 * ## Creating new source types
141 * One of the unusual features of the #GMainLoop functionality
142 * is that new types of event source can be created and used in
143 * addition to the builtin type of event source. A new event source
144 * type is used for handling GDK events. A new source type is created
145 * by "deriving" from the #GSource structure. The derived type of
146 * source is represented by a structure that has the #GSource structure
147 * as a first element, and other elements specific to the new source
148 * type. To create an instance of the new source type, call
149 * g_source_new() passing in the size of the derived structure and
150 * a table of functions. These #GSourceFuncs determine the behavior of
151 * the new source type.
153 * New source types basically interact with the main context
154 * in two ways. Their prepare function in #GSourceFuncs can set a timeout
155 * to determine the maximum amount of time that the main loop will sleep
156 * before checking the source again. In addition, or as well, the source
157 * can add file descriptors to the set that the main context checks using
158 * g_source_add_poll().
160 * ## Customizing the main loop iteration
162 * Single iterations of a #GMainContext can be run with
163 * g_main_context_iteration(). In some cases, more detailed control
164 * of exactly how the details of the main loop work is desired, for
165 * instance, when integrating the #GMainLoop with an external main loop.
166 * In such cases, you can call the component functions of
167 * g_main_context_iteration() directly. These functions are
168 * g_main_context_prepare(), g_main_context_query(),
169 * g_main_context_check() and g_main_context_dispatch().
171 * ## State of a Main Context # {#mainloop-states}
173 * The operation of these functions can best be seen in terms
174 * of a state diagram, as shown in this image.
176 * ![](mainloop-states.gif)
178 * On UNIX, the GLib mainloop is incompatible with fork(). Any program
179 * using the mainloop must either exec() or exit() from the child
180 * without returning to the mainloop.
185 typedef struct _GTimeoutSource GTimeoutSource;
186 typedef struct _GChildWatchSource GChildWatchSource;
187 typedef struct _GUnixSignalWatchSource GUnixSignalWatchSource;
188 typedef struct _GPollRec GPollRec;
189 typedef struct _GSourceCallback GSourceCallback;
193 G_SOURCE_READY = 1 << G_HOOK_FLAG_USER_SHIFT,
194 G_SOURCE_CAN_RECURSE = 1 << (G_HOOK_FLAG_USER_SHIFT + 1),
195 G_SOURCE_BLOCKED = 1 << (G_HOOK_FLAG_USER_SHIFT + 2)
198 typedef struct _GSourceList GSourceList;
202 GSource *head, *tail;
206 typedef struct _GMainWaiter GMainWaiter;
214 typedef struct _GMainDispatch GMainDispatch;
216 struct _GMainDispatch
222 #ifdef G_MAIN_POLL_DEBUG
223 gboolean _g_main_poll_debug = FALSE;
228 /* The following lock is used for both the list of sources
229 * and the list of poll records
239 GPtrArray *pending_dispatches;
240 gint timeout; /* Timeout for current iteration */
243 GHashTable *overflow_used_source_ids; /* set<guint> */
245 gint in_check_or_prepare;
247 GPollRec *poll_records, *poll_records_tail;
248 guint n_poll_records;
249 GPollFD *cached_poll_array;
250 guint cached_poll_array_size;
256 /* Flag indicating whether the set of fd's changed during a poll */
257 gboolean poll_changed;
262 gboolean time_is_fresh;
265 struct _GSourceCallback
270 GDestroyNotify notify;
275 GMainContext *context;
280 struct _GTimeoutSource
287 struct _GChildWatchSource
294 #else /* G_OS_WIN32 */
295 gboolean child_exited;
296 #endif /* G_OS_WIN32 */
299 struct _GUnixSignalWatchSource
314 struct _GSourcePrivate
316 GSList *child_sources;
317 GSource *parent_source;
321 /* This is currently only used on UNIX, but we always declare it (and
322 * let it remain empty on Windows) to avoid #ifdef all over the place.
327 typedef struct _GSourceIter
329 GMainContext *context;
335 #define LOCK_CONTEXT(context) g_mutex_lock (&context->mutex)
336 #define UNLOCK_CONTEXT(context) g_mutex_unlock (&context->mutex)
337 #define G_THREAD_SELF g_thread_self ()
339 #define SOURCE_DESTROYED(source) (((source)->flags & G_HOOK_FLAG_ACTIVE) == 0)
340 #define SOURCE_BLOCKED(source) (((source)->flags & G_SOURCE_BLOCKED) != 0)
342 #define SOURCE_UNREF(source, context) \
344 if ((source)->ref_count > 1) \
345 (source)->ref_count--; \
347 g_source_unref_internal ((source), (context), TRUE); \
351 /* Forward declarations */
353 static void g_source_unref_internal (GSource *source,
354 GMainContext *context,
356 static void g_source_destroy_internal (GSource *source,
357 GMainContext *context,
359 static void g_source_set_priority_unlocked (GSource *source,
360 GMainContext *context,
362 static void g_child_source_remove_internal (GSource *child_source,
363 GMainContext *context);
365 static void g_main_context_poll (GMainContext *context,
370 static void g_main_context_add_poll_unlocked (GMainContext *context,
373 static void g_main_context_remove_poll_unlocked (GMainContext *context,
376 static void g_source_iter_init (GSourceIter *iter,
377 GMainContext *context,
378 gboolean may_modify);
379 static gboolean g_source_iter_next (GSourceIter *iter,
381 static void g_source_iter_clear (GSourceIter *iter);
383 static gboolean g_timeout_dispatch (GSource *source,
384 GSourceFunc callback,
386 static gboolean g_child_watch_prepare (GSource *source,
388 static gboolean g_child_watch_check (GSource *source);
389 static gboolean g_child_watch_dispatch (GSource *source,
390 GSourceFunc callback,
392 static void g_child_watch_finalize (GSource *source);
394 static void g_unix_signal_handler (int signum);
395 static gboolean g_unix_signal_watch_prepare (GSource *source,
397 static gboolean g_unix_signal_watch_check (GSource *source);
398 static gboolean g_unix_signal_watch_dispatch (GSource *source,
399 GSourceFunc callback,
401 static void g_unix_signal_watch_finalize (GSource *source);
403 static gboolean g_idle_prepare (GSource *source,
405 static gboolean g_idle_check (GSource *source);
406 static gboolean g_idle_dispatch (GSource *source,
407 GSourceFunc callback,
410 static void block_source (GSource *source);
412 static GMainContext *glib_worker_context;
414 G_LOCK_DEFINE_STATIC (main_loop);
415 static GMainContext *default_main_context;
420 /* UNIX signals work by marking one of these variables then waking the
421 * worker context to check on them and dispatch accordingly.
423 #ifdef HAVE_SIG_ATOMIC_T
424 static volatile sig_atomic_t unix_signal_pending[NSIG];
425 static volatile sig_atomic_t any_unix_signal_pending;
427 static volatile int unix_signal_pending[NSIG];
428 static volatile int any_unix_signal_pending;
430 static volatile guint unix_signal_refcount[NSIG];
432 /* Guards all the data below */
433 G_LOCK_DEFINE_STATIC (unix_signal_lock);
434 static GSList *unix_signal_watches;
435 static GSList *unix_child_watches;
437 GSourceFuncs g_unix_signal_funcs =
439 g_unix_signal_watch_prepare,
440 g_unix_signal_watch_check,
441 g_unix_signal_watch_dispatch,
442 g_unix_signal_watch_finalize
444 #endif /* !G_OS_WIN32 */
445 G_LOCK_DEFINE_STATIC (main_context_list);
446 static GSList *main_context_list = NULL;
448 GSourceFuncs g_timeout_funcs =
456 GSourceFuncs g_child_watch_funcs =
458 g_child_watch_prepare,
460 g_child_watch_dispatch,
461 g_child_watch_finalize
464 GSourceFuncs g_idle_funcs =
473 * g_main_context_ref:
474 * @context: a #GMainContext
476 * Increases the reference count on a #GMainContext object by one.
478 * Returns: the @context that was passed in (since 2.6)
481 g_main_context_ref (GMainContext *context)
483 g_return_val_if_fail (context != NULL, NULL);
484 g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL);
486 g_atomic_int_inc (&context->ref_count);
492 poll_rec_list_free (GMainContext *context,
495 g_slice_free_chain (GPollRec, list, next);
499 * g_main_context_unref:
500 * @context: a #GMainContext
502 * Decreases the reference count on a #GMainContext object by one. If
503 * the result is zero, free the context and free all associated memory.
506 g_main_context_unref (GMainContext *context)
514 g_return_if_fail (context != NULL);
515 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
517 if (!g_atomic_int_dec_and_test (&context->ref_count))
520 G_LOCK (main_context_list);
521 main_context_list = g_slist_remove (main_context_list, context);
522 G_UNLOCK (main_context_list);
524 /* Free pending dispatches */
525 for (i = 0; i < context->pending_dispatches->len; i++)
526 g_source_unref_internal (context->pending_dispatches->pdata[i], context, FALSE);
528 /* g_source_iter_next() assumes the context is locked. */
529 LOCK_CONTEXT (context);
530 g_source_iter_init (&iter, context, TRUE);
531 while (g_source_iter_next (&iter, &source))
533 source->context = NULL;
534 g_source_destroy_internal (source, context, TRUE);
536 UNLOCK_CONTEXT (context);
538 for (sl_iter = context->source_lists; sl_iter; sl_iter = sl_iter->next)
540 list = sl_iter->data;
541 g_slice_free (GSourceList, list);
543 g_list_free (context->source_lists);
545 if (context->overflow_used_source_ids)
546 g_hash_table_destroy (context->overflow_used_source_ids);
548 g_mutex_clear (&context->mutex);
550 g_ptr_array_free (context->pending_dispatches, TRUE);
551 g_free (context->cached_poll_array);
553 poll_rec_list_free (context, context->poll_records);
555 g_wakeup_free (context->wakeup);
556 g_cond_clear (&context->cond);
561 /* Helper function used by mainloop/overflow test.
564 g_main_context_new_with_next_id (guint next_id)
566 GMainContext *ret = g_main_context_new ();
568 ret->next_id = next_id;
574 * g_main_context_new:
576 * Creates a new #GMainContext structure.
578 * Return value: the new #GMainContext
581 g_main_context_new (void)
583 static gsize initialised;
584 GMainContext *context;
586 if (g_once_init_enter (&initialised))
588 #ifdef G_MAIN_POLL_DEBUG
589 if (getenv ("G_MAIN_POLL_DEBUG") != NULL)
590 _g_main_poll_debug = TRUE;
593 g_once_init_leave (&initialised, TRUE);
596 context = g_new0 (GMainContext, 1);
598 g_mutex_init (&context->mutex);
599 g_cond_init (&context->cond);
601 context->owner = NULL;
602 context->waiters = NULL;
604 context->ref_count = 1;
606 context->next_id = 1;
608 context->source_lists = NULL;
610 context->poll_func = g_poll;
612 context->cached_poll_array = NULL;
613 context->cached_poll_array_size = 0;
615 context->pending_dispatches = g_ptr_array_new ();
617 context->time_is_fresh = FALSE;
619 context->wakeup = g_wakeup_new ();
620 g_wakeup_get_pollfd (context->wakeup, &context->wake_up_rec);
621 g_main_context_add_poll_unlocked (context, 0, &context->wake_up_rec);
623 G_LOCK (main_context_list);
624 main_context_list = g_slist_append (main_context_list, context);
626 #ifdef G_MAIN_POLL_DEBUG
627 if (_g_main_poll_debug)
628 g_print ("created context=%p\n", context);
631 G_UNLOCK (main_context_list);
637 * g_main_context_default:
639 * Returns the global default main context. This is the main context
640 * used for main loop functions when a main loop is not explicitly
641 * specified, and corresponds to the "main" main loop. See also
642 * g_main_context_get_thread_default().
644 * Return value: (transfer none): the global default main context.
647 g_main_context_default (void)
653 if (!default_main_context)
655 default_main_context = g_main_context_new ();
656 #ifdef G_MAIN_POLL_DEBUG
657 if (_g_main_poll_debug)
658 g_print ("default context=%p\n", default_main_context);
662 G_UNLOCK (main_loop);
664 return default_main_context;
668 free_context (gpointer data)
670 GMainContext *context = data;
672 g_main_context_release (context);
674 g_main_context_unref (context);
678 free_context_stack (gpointer data)
680 g_queue_free_full((GQueue *) data, (GDestroyNotify) free_context);
683 static GPrivate thread_context_stack = G_PRIVATE_INIT (free_context_stack);
686 * g_main_context_push_thread_default:
687 * @context: (allow-none): a #GMainContext, or %NULL for the global default context
689 * Acquires @context and sets it as the thread-default context for the
690 * current thread. This will cause certain asynchronous operations
691 * (such as most [gio][gio]-based I/O) which are
692 * started in this thread to run under @context and deliver their
693 * results to its main loop, rather than running under the global
694 * default context in the main thread. Note that calling this function
695 * changes the context returned by g_main_context_get_thread_default(),
696 * not the one returned by g_main_context_default(), so it does not affect
697 * the context used by functions like g_idle_add().
699 * Normally you would call this function shortly after creating a new
700 * thread, passing it a #GMainContext which will be run by a
701 * #GMainLoop in that thread, to set a new default context for all
702 * async operations in that thread. (In this case, you don't need to
703 * ever call g_main_context_pop_thread_default().) In some cases
704 * however, you may want to schedule a single operation in a
705 * non-default context, or temporarily use a non-default context in
706 * the main thread. In that case, you can wrap the call to the
707 * asynchronous operation inside a
708 * g_main_context_push_thread_default() /
709 * g_main_context_pop_thread_default() pair, but it is up to you to
710 * ensure that no other asynchronous operations accidentally get
711 * started while the non-default context is active.
713 * Beware that libraries that predate this function may not correctly
714 * handle being used from a thread with a thread-default context. Eg,
715 * see g_file_supports_thread_contexts().
720 g_main_context_push_thread_default (GMainContext *context)
723 gboolean acquired_context;
725 acquired_context = g_main_context_acquire (context);
726 g_return_if_fail (acquired_context);
728 if (context == g_main_context_default ())
731 g_main_context_ref (context);
733 stack = g_private_get (&thread_context_stack);
736 stack = g_queue_new ();
737 g_private_set (&thread_context_stack, stack);
740 g_queue_push_head (stack, context);
744 * g_main_context_pop_thread_default:
745 * @context: (allow-none): a #GMainContext object, or %NULL
747 * Pops @context off the thread-default context stack (verifying that
748 * it was on the top of the stack).
753 g_main_context_pop_thread_default (GMainContext *context)
757 if (context == g_main_context_default ())
760 stack = g_private_get (&thread_context_stack);
762 g_return_if_fail (stack != NULL);
763 g_return_if_fail (g_queue_peek_head (stack) == context);
765 g_queue_pop_head (stack);
767 g_main_context_release (context);
769 g_main_context_unref (context);
773 * g_main_context_get_thread_default:
775 * Gets the thread-default #GMainContext for this thread. Asynchronous
776 * operations that want to be able to be run in contexts other than
777 * the default one should call this method or
778 * g_main_context_ref_thread_default() to get a #GMainContext to add
779 * their #GSources to. (Note that even in single-threaded
780 * programs applications may sometimes want to temporarily push a
781 * non-default context, so it is not safe to assume that this will
782 * always return %NULL if you are running in the default thread.)
784 * If you need to hold a reference on the context, use
785 * g_main_context_ref_thread_default() instead.
787 * Returns: (transfer none): the thread-default #GMainContext, or
788 * %NULL if the thread-default context is the global default context.
793 g_main_context_get_thread_default (void)
797 stack = g_private_get (&thread_context_stack);
799 return g_queue_peek_head (stack);
805 * g_main_context_ref_thread_default:
807 * Gets the thread-default #GMainContext for this thread, as with
808 * g_main_context_get_thread_default(), but also adds a reference to
809 * it with g_main_context_ref(). In addition, unlike
810 * g_main_context_get_thread_default(), if the thread-default context
811 * is the global default context, this will return that #GMainContext
812 * (with a ref added to it) rather than returning %NULL.
814 * Returns: (transfer full): the thread-default #GMainContext. Unref
815 * with g_main_context_unref() when you are done with it.
820 g_main_context_ref_thread_default (void)
822 GMainContext *context;
824 context = g_main_context_get_thread_default ();
826 context = g_main_context_default ();
827 return g_main_context_ref (context);
830 /* Hooks for adding to the main loop */
834 * @source_funcs: structure containing functions that implement
835 * the sources behavior.
836 * @struct_size: size of the #GSource structure to create.
838 * Creates a new #GSource structure. The size is specified to
839 * allow creating structures derived from #GSource that contain
840 * additional data. The size passed in must be at least
841 * `sizeof (GSource)`.
843 * The source will not initially be associated with any #GMainContext
844 * and must be added to one with g_source_attach() before it will be
847 * Return value: the newly-created #GSource.
850 g_source_new (GSourceFuncs *source_funcs,
855 g_return_val_if_fail (source_funcs != NULL, NULL);
856 g_return_val_if_fail (struct_size >= sizeof (GSource), NULL);
858 source = (GSource*) g_malloc0 (struct_size);
859 source->priv = g_slice_new0 (GSourcePrivate);
860 source->source_funcs = source_funcs;
861 source->ref_count = 1;
863 source->priority = G_PRIORITY_DEFAULT;
865 source->flags = G_HOOK_FLAG_ACTIVE;
867 source->priv->ready_time = -1;
869 /* NULL/0 initialization for all other fields */
874 /* Holds context's lock */
876 g_source_iter_init (GSourceIter *iter,
877 GMainContext *context,
880 iter->context = context;
881 iter->current_list = NULL;
883 iter->may_modify = may_modify;
886 /* Holds context's lock */
888 g_source_iter_next (GSourceIter *iter, GSource **source)
890 GSource *next_source;
893 next_source = iter->source->next;
899 if (iter->current_list)
900 iter->current_list = iter->current_list->next;
902 iter->current_list = iter->context->source_lists;
904 if (iter->current_list)
906 GSourceList *source_list = iter->current_list->data;
908 next_source = source_list->head;
912 /* Note: unreffing iter->source could potentially cause its
913 * GSourceList to be removed from source_lists (if iter->source is
914 * the only source in its list, and it is destroyed), so we have to
915 * keep it reffed until after we advance iter->current_list, above.
918 if (iter->source && iter->may_modify)
919 SOURCE_UNREF (iter->source, iter->context);
920 iter->source = next_source;
921 if (iter->source && iter->may_modify)
922 iter->source->ref_count++;
924 *source = iter->source;
925 return *source != NULL;
928 /* Holds context's lock. Only necessary to call if you broke out of
929 * the g_source_iter_next() loop early.
932 g_source_iter_clear (GSourceIter *iter)
934 if (iter->source && iter->may_modify)
936 SOURCE_UNREF (iter->source, iter->context);
941 /* Holds context's lock
944 find_source_list_for_priority (GMainContext *context,
949 GSourceList *source_list;
952 for (iter = context->source_lists; iter != NULL; last = iter, iter = iter->next)
954 source_list = iter->data;
956 if (source_list->priority == priority)
959 if (source_list->priority > priority)
964 source_list = g_slice_new0 (GSourceList);
965 source_list->priority = priority;
966 context->source_lists = g_list_insert_before (context->source_lists,
976 source_list = g_slice_new0 (GSourceList);
977 source_list->priority = priority;
980 context->source_lists = g_list_append (NULL, source_list);
983 /* This just appends source_list to the end of
984 * context->source_lists without having to walk the list again.
986 last = g_list_append (last, source_list);
991 /* Holds context's lock
994 source_add_to_context (GSource *source,
995 GMainContext *context)
997 GSourceList *source_list;
998 GSource *prev, *next;
1000 source_list = find_source_list_for_priority (context, source->priority, TRUE);
1002 if (source->priv->parent_source)
1004 g_assert (source_list->head != NULL);
1006 /* Put the source immediately before its parent */
1007 prev = source->priv->parent_source->prev;
1008 next = source->priv->parent_source;
1012 prev = source_list->tail;
1016 source->next = next;
1018 next->prev = source;
1020 source_list->tail = source;
1022 source->prev = prev;
1024 prev->next = source;
1026 source_list->head = source;
1029 /* Holds context's lock
1032 source_remove_from_context (GSource *source,
1033 GMainContext *context)
1035 GSourceList *source_list;
1037 source_list = find_source_list_for_priority (context, source->priority, FALSE);
1038 g_return_if_fail (source_list != NULL);
1041 source->prev->next = source->next;
1043 source_list->head = source->next;
1046 source->next->prev = source->prev;
1048 source_list->tail = source->prev;
1050 source->prev = NULL;
1051 source->next = NULL;
1053 if (source_list->head == NULL)
1055 context->source_lists = g_list_remove (context->source_lists, source_list);
1056 g_slice_free (GSourceList, source_list);
1059 if (context->overflow_used_source_ids)
1060 g_hash_table_remove (context->overflow_used_source_ids,
1061 GUINT_TO_POINTER (source->source_id));
1066 assign_source_id_unlocked (GMainContext *context,
1071 /* Are we about to overflow back to 0?
1072 * See https://bugzilla.gnome.org/show_bug.cgi?id=687098
1074 if (G_UNLIKELY (context->next_id == G_MAXUINT &&
1075 context->overflow_used_source_ids == NULL))
1080 context->overflow_used_source_ids = g_hash_table_new (NULL, NULL);
1082 g_source_iter_init (&iter, context, FALSE);
1083 while (g_source_iter_next (&iter, &source))
1085 g_hash_table_add (context->overflow_used_source_ids,
1086 GUINT_TO_POINTER (source->source_id));
1089 g_hash_table_add (context->overflow_used_source_ids, GUINT_TO_POINTER (id));
1091 else if (context->overflow_used_source_ids == NULL)
1093 id = context->next_id++;
1098 * If we overran G_MAXUINT, we fall back to randomly probing the
1099 * source ids for the current context. This will be slower the more
1100 * sources there are, but we're mainly concerned right now about
1101 * correctness and code size. There's time for a more clever solution
1105 id = g_random_int ();
1107 g_hash_table_contains (context->overflow_used_source_ids,
1108 GUINT_TO_POINTER (id)));
1109 g_hash_table_add (context->overflow_used_source_ids, GUINT_TO_POINTER (id));
1112 source->source_id = id;
1116 g_source_attach_unlocked (GSource *source,
1117 GMainContext *context,
1122 source->context = context;
1123 assign_source_id_unlocked (context, source);
1124 source->ref_count++;
1125 source_add_to_context (source, context);
1127 if (!SOURCE_BLOCKED (source))
1129 tmp_list = source->poll_fds;
1132 g_main_context_add_poll_unlocked (context, source->priority, tmp_list->data);
1133 tmp_list = tmp_list->next;
1136 for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
1137 g_main_context_add_poll_unlocked (context, source->priority, tmp_list->data);
1140 tmp_list = source->priv->child_sources;
1143 g_source_attach_unlocked (tmp_list->data, context, FALSE);
1144 tmp_list = tmp_list->next;
1147 /* If another thread has acquired the context, wake it up since it
1148 * might be in poll() right now.
1150 if (do_wakeup && context->owner && context->owner != G_THREAD_SELF)
1151 g_wakeup_signal (context->wakeup);
1153 return source->source_id;
1158 * @source: a #GSource
1159 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
1161 * Adds a #GSource to a @context so that it will be executed within
1162 * that context. Remove it by calling g_source_destroy().
1164 * Return value: the ID (greater than 0) for the source within the
1168 g_source_attach (GSource *source,
1169 GMainContext *context)
1173 g_return_val_if_fail (source->context == NULL, 0);
1174 g_return_val_if_fail (!SOURCE_DESTROYED (source), 0);
1176 TRACE (GLIB_MAIN_SOURCE_ATTACH (g_source_get_name (source)));
1179 context = g_main_context_default ();
1181 LOCK_CONTEXT (context);
1183 result = g_source_attach_unlocked (source, context, TRUE);
1185 UNLOCK_CONTEXT (context);
1191 g_source_destroy_internal (GSource *source,
1192 GMainContext *context,
1195 TRACE (GLIB_MAIN_SOURCE_DESTROY (g_source_get_name (source)));
1198 LOCK_CONTEXT (context);
1200 if (!SOURCE_DESTROYED (source))
1203 gpointer old_cb_data;
1204 GSourceCallbackFuncs *old_cb_funcs;
1206 source->flags &= ~G_HOOK_FLAG_ACTIVE;
1208 old_cb_data = source->callback_data;
1209 old_cb_funcs = source->callback_funcs;
1211 source->callback_data = NULL;
1212 source->callback_funcs = NULL;
1216 UNLOCK_CONTEXT (context);
1217 old_cb_funcs->unref (old_cb_data);
1218 LOCK_CONTEXT (context);
1221 if (!SOURCE_BLOCKED (source))
1223 tmp_list = source->poll_fds;
1226 g_main_context_remove_poll_unlocked (context, tmp_list->data);
1227 tmp_list = tmp_list->next;
1230 for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
1231 g_main_context_remove_poll_unlocked (context, tmp_list->data);
1234 while (source->priv->child_sources)
1235 g_child_source_remove_internal (source->priv->child_sources->data, context);
1237 if (source->priv->parent_source)
1238 g_child_source_remove_internal (source, context);
1240 g_source_unref_internal (source, context, TRUE);
1244 UNLOCK_CONTEXT (context);
1249 * @source: a #GSource
1251 * Removes a source from its #GMainContext, if any, and mark it as
1252 * destroyed. The source cannot be subsequently added to another
1253 * context. It is safe to call this on sources which have already been
1254 * removed from their context.
1257 g_source_destroy (GSource *source)
1259 GMainContext *context;
1261 g_return_if_fail (source != NULL);
1263 context = source->context;
1266 g_source_destroy_internal (source, context, FALSE);
1268 source->flags &= ~G_HOOK_FLAG_ACTIVE;
1273 * @source: a #GSource
1275 * Returns the numeric ID for a particular source. The ID of a source
1276 * is a positive integer which is unique within a particular main loop
1277 * context. The reverse
1278 * mapping from ID to source is done by g_main_context_find_source_by_id().
1280 * Return value: the ID (greater than 0) for the source
1283 g_source_get_id (GSource *source)
1287 g_return_val_if_fail (source != NULL, 0);
1288 g_return_val_if_fail (source->context != NULL, 0);
1290 LOCK_CONTEXT (source->context);
1291 result = source->source_id;
1292 UNLOCK_CONTEXT (source->context);
1298 * g_source_get_context:
1299 * @source: a #GSource
1301 * Gets the #GMainContext with which the source is associated.
1303 * You can call this on a source that has been destroyed, provided
1304 * that the #GMainContext it was attached to still exists (in which
1305 * case it will return that #GMainContext). In particular, you can
1306 * always call this function on the source returned from
1307 * g_main_current_source(). But calling this function on a source
1308 * whose #GMainContext has been destroyed is an error.
1310 * Return value: (transfer none) (allow-none): the #GMainContext with which the
1311 * source is associated, or %NULL if the context has not
1312 * yet been added to a source.
1315 g_source_get_context (GSource *source)
1317 g_return_val_if_fail (source->context != NULL || !SOURCE_DESTROYED (source), NULL);
1319 return source->context;
1323 * g_source_add_poll:
1324 * @source:a #GSource
1325 * @fd: a #GPollFD structure holding information about a file
1326 * descriptor to watch.
1328 * Adds a file descriptor to the set of file descriptors polled for
1329 * this source. This is usually combined with g_source_new() to add an
1330 * event source. The event source's check function will typically test
1331 * the @revents field in the #GPollFD struct and return %TRUE if events need
1334 * Using this API forces the linear scanning of event sources on each
1335 * main loop iteration. Newly-written event sources should try to use
1336 * g_source_add_unix_fd() instead of this API.
1339 g_source_add_poll (GSource *source,
1342 GMainContext *context;
1344 g_return_if_fail (source != NULL);
1345 g_return_if_fail (fd != NULL);
1346 g_return_if_fail (!SOURCE_DESTROYED (source));
1348 context = source->context;
1351 LOCK_CONTEXT (context);
1353 source->poll_fds = g_slist_prepend (source->poll_fds, fd);
1357 if (!SOURCE_BLOCKED (source))
1358 g_main_context_add_poll_unlocked (context, source->priority, fd);
1359 UNLOCK_CONTEXT (context);
1364 * g_source_remove_poll:
1365 * @source:a #GSource
1366 * @fd: a #GPollFD structure previously passed to g_source_add_poll().
1368 * Removes a file descriptor from the set of file descriptors polled for
1372 g_source_remove_poll (GSource *source,
1375 GMainContext *context;
1377 g_return_if_fail (source != NULL);
1378 g_return_if_fail (fd != NULL);
1379 g_return_if_fail (!SOURCE_DESTROYED (source));
1381 context = source->context;
1384 LOCK_CONTEXT (context);
1386 source->poll_fds = g_slist_remove (source->poll_fds, fd);
1390 if (!SOURCE_BLOCKED (source))
1391 g_main_context_remove_poll_unlocked (context, fd);
1392 UNLOCK_CONTEXT (context);
1397 * g_source_add_child_source:
1398 * @source:a #GSource
1399 * @child_source: a second #GSource that @source should "poll"
1401 * Adds @child_source to @source as a "polled" source; when @source is
1402 * added to a #GMainContext, @child_source will be automatically added
1403 * with the same priority, when @child_source is triggered, it will
1404 * cause @source to dispatch (in addition to calling its own
1405 * callback), and when @source is destroyed, it will destroy
1406 * @child_source as well. (@source will also still be dispatched if
1407 * its own prepare/check functions indicate that it is ready.)
1409 * If you don't need @child_source to do anything on its own when it
1410 * triggers, you can call g_source_set_dummy_callback() on it to set a
1411 * callback that does nothing (except return %TRUE if appropriate).
1413 * @source will hold a reference on @child_source while @child_source
1414 * is attached to it.
1419 g_source_add_child_source (GSource *source,
1420 GSource *child_source)
1422 GMainContext *context;
1424 g_return_if_fail (source != NULL);
1425 g_return_if_fail (child_source != NULL);
1426 g_return_if_fail (!SOURCE_DESTROYED (source));
1427 g_return_if_fail (!SOURCE_DESTROYED (child_source));
1428 g_return_if_fail (child_source->context == NULL);
1429 g_return_if_fail (child_source->priv->parent_source == NULL);
1431 context = source->context;
1434 LOCK_CONTEXT (context);
1436 source->priv->child_sources = g_slist_prepend (source->priv->child_sources,
1437 g_source_ref (child_source));
1438 child_source->priv->parent_source = source;
1439 g_source_set_priority_unlocked (child_source, NULL, source->priority);
1440 if (SOURCE_BLOCKED (source))
1441 block_source (child_source);
1445 g_source_attach_unlocked (child_source, context, TRUE);
1446 UNLOCK_CONTEXT (context);
1451 g_child_source_remove_internal (GSource *child_source,
1452 GMainContext *context)
1454 GSource *parent_source = child_source->priv->parent_source;
1456 parent_source->priv->child_sources =
1457 g_slist_remove (parent_source->priv->child_sources, child_source);
1458 child_source->priv->parent_source = NULL;
1460 g_source_destroy_internal (child_source, context, TRUE);
1461 g_source_unref_internal (child_source, context, TRUE);
1465 * g_source_remove_child_source:
1466 * @source:a #GSource
1467 * @child_source: a #GSource previously passed to
1468 * g_source_add_child_source().
1470 * Detaches @child_source from @source and destroys it.
1475 g_source_remove_child_source (GSource *source,
1476 GSource *child_source)
1478 GMainContext *context;
1480 g_return_if_fail (source != NULL);
1481 g_return_if_fail (child_source != NULL);
1482 g_return_if_fail (child_source->priv->parent_source == source);
1483 g_return_if_fail (!SOURCE_DESTROYED (source));
1484 g_return_if_fail (!SOURCE_DESTROYED (child_source));
1486 context = source->context;
1489 LOCK_CONTEXT (context);
1491 g_child_source_remove_internal (child_source, context);
1494 UNLOCK_CONTEXT (context);
1498 * g_source_set_callback_indirect:
1499 * @source: the source
1500 * @callback_data: pointer to callback data "object"
1501 * @callback_funcs: functions for reference counting @callback_data
1502 * and getting the callback and data
1504 * Sets the callback function storing the data as a refcounted callback
1505 * "object". This is used internally. Note that calling
1506 * g_source_set_callback_indirect() assumes
1507 * an initial reference count on @callback_data, and thus
1508 * @callback_funcs->unref will eventually be called once more
1509 * than @callback_funcs->ref.
1512 g_source_set_callback_indirect (GSource *source,
1513 gpointer callback_data,
1514 GSourceCallbackFuncs *callback_funcs)
1516 GMainContext *context;
1517 gpointer old_cb_data;
1518 GSourceCallbackFuncs *old_cb_funcs;
1520 g_return_if_fail (source != NULL);
1521 g_return_if_fail (callback_funcs != NULL || callback_data == NULL);
1523 context = source->context;
1526 LOCK_CONTEXT (context);
1528 old_cb_data = source->callback_data;
1529 old_cb_funcs = source->callback_funcs;
1531 source->callback_data = callback_data;
1532 source->callback_funcs = callback_funcs;
1535 UNLOCK_CONTEXT (context);
1538 old_cb_funcs->unref (old_cb_data);
1542 g_source_callback_ref (gpointer cb_data)
1544 GSourceCallback *callback = cb_data;
1546 callback->ref_count++;
1551 g_source_callback_unref (gpointer cb_data)
1553 GSourceCallback *callback = cb_data;
1555 callback->ref_count--;
1556 if (callback->ref_count == 0)
1558 if (callback->notify)
1559 callback->notify (callback->data);
1565 g_source_callback_get (gpointer cb_data,
1570 GSourceCallback *callback = cb_data;
1572 *func = callback->func;
1573 *data = callback->data;
1576 static GSourceCallbackFuncs g_source_callback_funcs = {
1577 g_source_callback_ref,
1578 g_source_callback_unref,
1579 g_source_callback_get,
1583 * g_source_set_callback:
1584 * @source: the source
1585 * @func: a callback function
1586 * @data: the data to pass to callback function
1587 * @notify: (allow-none): a function to call when @data is no longer in use, or %NULL.
1589 * Sets the callback function for a source. The callback for a source is
1590 * called from the source's dispatch function.
1592 * The exact type of @func depends on the type of source; ie. you
1593 * should not count on @func being called with @data as its first
1596 * Typically, you won't use this function. Instead use functions specific
1597 * to the type of source you are using.
1600 g_source_set_callback (GSource *source,
1603 GDestroyNotify notify)
1605 GSourceCallback *new_callback;
1607 g_return_if_fail (source != NULL);
1609 new_callback = g_new (GSourceCallback, 1);
1611 new_callback->ref_count = 1;
1612 new_callback->func = func;
1613 new_callback->data = data;
1614 new_callback->notify = notify;
1616 g_source_set_callback_indirect (source, new_callback, &g_source_callback_funcs);
1621 * g_source_set_funcs:
1622 * @source: a #GSource
1623 * @funcs: the new #GSourceFuncs
1625 * Sets the source functions (can be used to override
1626 * default implementations) of an unattached source.
1631 g_source_set_funcs (GSource *source,
1632 GSourceFuncs *funcs)
1634 g_return_if_fail (source != NULL);
1635 g_return_if_fail (source->context == NULL);
1636 g_return_if_fail (source->ref_count > 0);
1637 g_return_if_fail (funcs != NULL);
1639 source->source_funcs = funcs;
1643 g_source_set_priority_unlocked (GSource *source,
1644 GMainContext *context,
1649 g_return_if_fail (source->priv->parent_source == NULL ||
1650 source->priv->parent_source->priority == priority);
1654 /* Remove the source from the context's source and then
1655 * add it back after so it is sorted in the correct place
1657 source_remove_from_context (source, source->context);
1660 source->priority = priority;
1664 source_add_to_context (source, source->context);
1666 if (!SOURCE_BLOCKED (source))
1668 tmp_list = source->poll_fds;
1671 g_main_context_remove_poll_unlocked (context, tmp_list->data);
1672 g_main_context_add_poll_unlocked (context, priority, tmp_list->data);
1674 tmp_list = tmp_list->next;
1677 for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
1679 g_main_context_remove_poll_unlocked (context, tmp_list->data);
1680 g_main_context_add_poll_unlocked (context, priority, tmp_list->data);
1685 if (source->priv->child_sources)
1687 tmp_list = source->priv->child_sources;
1690 g_source_set_priority_unlocked (tmp_list->data, context, priority);
1691 tmp_list = tmp_list->next;
1697 * g_source_set_priority:
1698 * @source: a #GSource
1699 * @priority: the new priority.
1701 * Sets the priority of a source. While the main loop is being run, a
1702 * source will be dispatched if it is ready to be dispatched and no
1703 * sources at a higher (numerically smaller) priority are ready to be
1707 g_source_set_priority (GSource *source,
1710 GMainContext *context;
1712 g_return_if_fail (source != NULL);
1714 context = source->context;
1717 LOCK_CONTEXT (context);
1718 g_source_set_priority_unlocked (source, context, priority);
1720 UNLOCK_CONTEXT (source->context);
1724 * g_source_get_priority:
1725 * @source: a #GSource
1727 * Gets the priority of a source.
1729 * Return value: the priority of the source
1732 g_source_get_priority (GSource *source)
1734 g_return_val_if_fail (source != NULL, 0);
1736 return source->priority;
1740 * g_source_set_ready_time:
1741 * @source: a #GSource
1742 * @ready_time: the monotonic time at which the source will be ready,
1743 * 0 for "immediately", -1 for "never"
1745 * Sets a #GSource to be dispatched when the given monotonic time is
1746 * reached (or passed). If the monotonic time is in the past (as it
1747 * always will be if @ready_time is 0) then the source will be
1748 * dispatched immediately.
1750 * If @ready_time is -1 then the source is never woken up on the basis
1751 * of the passage of time.
1753 * Dispatching the source does not reset the ready time. You should do
1754 * so yourself, from the source dispatch function.
1756 * Note that if you have a pair of sources where the ready time of one
1757 * suggests that it will be delivered first but the priority for the
1758 * other suggests that it would be delivered first, and the ready time
1759 * for both sources is reached during the same main context iteration
1760 * then the order of dispatch is undefined.
1765 g_source_set_ready_time (GSource *source,
1768 GMainContext *context;
1770 g_return_if_fail (source != NULL);
1771 g_return_if_fail (source->ref_count > 0);
1773 if (source->priv->ready_time == ready_time)
1776 context = source->context;
1779 LOCK_CONTEXT (context);
1781 source->priv->ready_time = ready_time;
1785 /* Quite likely that we need to change the timeout on the poll */
1786 if (!SOURCE_BLOCKED (source))
1787 g_wakeup_signal (context->wakeup);
1788 UNLOCK_CONTEXT (context);
1793 * g_source_get_ready_time:
1794 * @source: a #GSource
1796 * Gets the "ready time" of @source, as set by
1797 * g_source_set_ready_time().
1799 * Any time before the current monotonic time (including 0) is an
1800 * indication that the source will fire immediately.
1802 * Returns: the monotonic ready time, -1 for "never"
1805 g_source_get_ready_time (GSource *source)
1807 g_return_val_if_fail (source != NULL, -1);
1809 return source->priv->ready_time;
1813 * g_source_set_can_recurse:
1814 * @source: a #GSource
1815 * @can_recurse: whether recursion is allowed for this source
1817 * Sets whether a source can be called recursively. If @can_recurse is
1818 * %TRUE, then while the source is being dispatched then this source
1819 * will be processed normally. Otherwise, all processing of this
1820 * source is blocked until the dispatch function returns.
1823 g_source_set_can_recurse (GSource *source,
1824 gboolean can_recurse)
1826 GMainContext *context;
1828 g_return_if_fail (source != NULL);
1830 context = source->context;
1833 LOCK_CONTEXT (context);
1836 source->flags |= G_SOURCE_CAN_RECURSE;
1838 source->flags &= ~G_SOURCE_CAN_RECURSE;
1841 UNLOCK_CONTEXT (context);
1845 * g_source_get_can_recurse:
1846 * @source: a #GSource
1848 * Checks whether a source is allowed to be called recursively.
1849 * see g_source_set_can_recurse().
1851 * Return value: whether recursion is allowed.
1854 g_source_get_can_recurse (GSource *source)
1856 g_return_val_if_fail (source != NULL, FALSE);
1858 return (source->flags & G_SOURCE_CAN_RECURSE) != 0;
1863 * g_source_set_name:
1864 * @source: a #GSource
1865 * @name: debug name for the source
1867 * Sets a name for the source, used in debugging and profiling.
1868 * The name defaults to #NULL.
1870 * The source name should describe in a human-readable way
1871 * what the source does. For example, "X11 event queue"
1872 * or "GTK+ repaint idle handler" or whatever it is.
1874 * It is permitted to call this function multiple times, but is not
1875 * recommended due to the potential performance impact. For example,
1876 * one could change the name in the "check" function of a #GSourceFuncs
1877 * to include details like the event type in the source name.
1882 g_source_set_name (GSource *source,
1885 g_return_if_fail (source != NULL);
1887 /* setting back to NULL is allowed, just because it's
1888 * weird if get_name can return NULL but you can't
1892 g_free (source->name);
1893 source->name = g_strdup (name);
1897 * g_source_get_name:
1898 * @source: a #GSource
1900 * Gets a name for the source, used in debugging and profiling.
1901 * The name may be #NULL if it has never been set with
1902 * g_source_set_name().
1904 * Return value: the name of the source
1908 g_source_get_name (GSource *source)
1910 g_return_val_if_fail (source != NULL, NULL);
1912 return source->name;
1916 * g_source_set_name_by_id:
1917 * @tag: a #GSource ID
1918 * @name: debug name for the source
1920 * Sets the name of a source using its ID.
1922 * This is a convenience utility to set source names from the return
1923 * value of g_idle_add(), g_timeout_add(), etc.
1928 g_source_set_name_by_id (guint tag,
1933 g_return_if_fail (tag > 0);
1935 source = g_main_context_find_source_by_id (NULL, tag);
1939 g_source_set_name (source, name);
1945 * @source: a #GSource
1947 * Increases the reference count on a source by one.
1949 * Return value: @source
1952 g_source_ref (GSource *source)
1954 GMainContext *context;
1956 g_return_val_if_fail (source != NULL, NULL);
1958 context = source->context;
1961 LOCK_CONTEXT (context);
1963 source->ref_count++;
1966 UNLOCK_CONTEXT (context);
1971 /* g_source_unref() but possible to call within context lock
1974 g_source_unref_internal (GSource *source,
1975 GMainContext *context,
1978 gpointer old_cb_data = NULL;
1979 GSourceCallbackFuncs *old_cb_funcs = NULL;
1981 g_return_if_fail (source != NULL);
1983 if (!have_lock && context)
1984 LOCK_CONTEXT (context);
1986 source->ref_count--;
1987 if (source->ref_count == 0)
1989 old_cb_data = source->callback_data;
1990 old_cb_funcs = source->callback_funcs;
1992 source->callback_data = NULL;
1993 source->callback_funcs = NULL;
1997 if (!SOURCE_DESTROYED (source))
1998 g_warning (G_STRLOC ": ref_count == 0, but source was still attached to a context!");
1999 source_remove_from_context (source, context);
2002 if (source->source_funcs->finalize)
2005 UNLOCK_CONTEXT (context);
2006 source->source_funcs->finalize (source);
2008 LOCK_CONTEXT (context);
2011 g_free (source->name);
2012 source->name = NULL;
2014 g_slist_free (source->poll_fds);
2015 source->poll_fds = NULL;
2017 g_slist_free_full (source->priv->fds, g_free);
2019 g_slice_free (GSourcePrivate, source->priv);
2020 source->priv = NULL;
2025 if (!have_lock && context)
2026 UNLOCK_CONTEXT (context);
2031 UNLOCK_CONTEXT (context);
2033 old_cb_funcs->unref (old_cb_data);
2036 LOCK_CONTEXT (context);
2042 * @source: a #GSource
2044 * Decreases the reference count of a source by one. If the
2045 * resulting reference count is zero the source and associated
2046 * memory will be destroyed.
2049 g_source_unref (GSource *source)
2051 g_return_if_fail (source != NULL);
2053 g_source_unref_internal (source, source->context, FALSE);
2057 * g_main_context_find_source_by_id:
2058 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
2059 * @source_id: the source ID, as returned by g_source_get_id().
2061 * Finds a #GSource given a pair of context and ID.
2063 * Return value: (transfer none): the #GSource if found, otherwise, %NULL
2066 g_main_context_find_source_by_id (GMainContext *context,
2072 g_return_val_if_fail (source_id > 0, NULL);
2074 if (context == NULL)
2075 context = g_main_context_default ();
2077 LOCK_CONTEXT (context);
2079 g_source_iter_init (&iter, context, FALSE);
2080 while (g_source_iter_next (&iter, &source))
2082 if (!SOURCE_DESTROYED (source) &&
2083 source->source_id == source_id)
2086 g_source_iter_clear (&iter);
2088 UNLOCK_CONTEXT (context);
2094 * g_main_context_find_source_by_funcs_user_data:
2095 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used).
2096 * @funcs: the @source_funcs passed to g_source_new().
2097 * @user_data: the user data from the callback.
2099 * Finds a source with the given source functions and user data. If
2100 * multiple sources exist with the same source function and user data,
2101 * the first one found will be returned.
2103 * Return value: (transfer none): the source, if one was found, otherwise %NULL
2106 g_main_context_find_source_by_funcs_user_data (GMainContext *context,
2107 GSourceFuncs *funcs,
2113 g_return_val_if_fail (funcs != NULL, NULL);
2115 if (context == NULL)
2116 context = g_main_context_default ();
2118 LOCK_CONTEXT (context);
2120 g_source_iter_init (&iter, context, FALSE);
2121 while (g_source_iter_next (&iter, &source))
2123 if (!SOURCE_DESTROYED (source) &&
2124 source->source_funcs == funcs &&
2125 source->callback_funcs)
2127 GSourceFunc callback;
2128 gpointer callback_data;
2130 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
2132 if (callback_data == user_data)
2136 g_source_iter_clear (&iter);
2138 UNLOCK_CONTEXT (context);
2144 * g_main_context_find_source_by_user_data:
2145 * @context: a #GMainContext
2146 * @user_data: the user_data for the callback.
2148 * Finds a source with the given user data for the callback. If
2149 * multiple sources exist with the same user data, the first
2150 * one found will be returned.
2152 * Return value: (transfer none): the source, if one was found, otherwise %NULL
2155 g_main_context_find_source_by_user_data (GMainContext *context,
2161 if (context == NULL)
2162 context = g_main_context_default ();
2164 LOCK_CONTEXT (context);
2166 g_source_iter_init (&iter, context, FALSE);
2167 while (g_source_iter_next (&iter, &source))
2169 if (!SOURCE_DESTROYED (source) &&
2170 source->callback_funcs)
2172 GSourceFunc callback;
2173 gpointer callback_data = NULL;
2175 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
2177 if (callback_data == user_data)
2181 g_source_iter_clear (&iter);
2183 UNLOCK_CONTEXT (context);
2190 * @tag: the ID of the source to remove.
2192 * Removes the source with the given id from the default main context.
2194 * The id of a #GSource is given by g_source_get_id(), or will be
2195 * returned by the functions g_source_attach(), g_idle_add(),
2196 * g_idle_add_full(), g_timeout_add(), g_timeout_add_full(),
2197 * g_child_watch_add(), g_child_watch_add_full(), g_io_add_watch(), and
2198 * g_io_add_watch_full().
2200 * See also g_source_destroy(). You must use g_source_destroy() for sources
2201 * added to a non-default main context.
2203 * It is a programmer error to attempt to remove a non-existent source.
2205 * Return value: For historical reasons, this function always returns %TRUE
2208 g_source_remove (guint tag)
2212 g_return_val_if_fail (tag > 0, FALSE);
2214 source = g_main_context_find_source_by_id (NULL, tag);
2216 g_source_destroy (source);
2218 g_critical ("Source ID %u was not found when attempting to remove it", tag);
2220 return source != NULL;
2224 * g_source_remove_by_user_data:
2225 * @user_data: the user_data for the callback.
2227 * Removes a source from the default main loop context given the user
2228 * data for the callback. If multiple sources exist with the same user
2229 * data, only one will be destroyed.
2231 * Return value: %TRUE if a source was found and removed.
2234 g_source_remove_by_user_data (gpointer user_data)
2238 source = g_main_context_find_source_by_user_data (NULL, user_data);
2241 g_source_destroy (source);
2249 * g_source_remove_by_funcs_user_data:
2250 * @funcs: The @source_funcs passed to g_source_new()
2251 * @user_data: the user data for the callback
2253 * Removes a source from the default main loop context given the
2254 * source functions and user data. If multiple sources exist with the
2255 * same source functions and user data, only one will be destroyed.
2257 * Return value: %TRUE if a source was found and removed.
2260 g_source_remove_by_funcs_user_data (GSourceFuncs *funcs,
2265 g_return_val_if_fail (funcs != NULL, FALSE);
2267 source = g_main_context_find_source_by_funcs_user_data (NULL, funcs, user_data);
2270 g_source_destroy (source);
2279 * g_source_add_unix_fd:
2280 * @source: a #GSource
2281 * @fd: the fd to monitor
2282 * @events: an event mask
2284 * Monitors @fd for the IO events in @events.
2286 * The tag returned by this function can be used to remove or modify the
2287 * monitoring of the fd using g_source_remove_unix_fd() or
2288 * g_source_modify_unix_fd().
2290 * It is not necessary to remove the fd before destroying the source; it
2291 * will be cleaned up automatically.
2293 * As the name suggests, this function is not available on Windows.
2295 * Returns: an opaque tag
2300 g_source_add_unix_fd (GSource *source,
2302 GIOCondition events)
2304 GMainContext *context;
2307 g_return_val_if_fail (source != NULL, NULL);
2308 g_return_val_if_fail (!SOURCE_DESTROYED (source), NULL);
2310 poll_fd = g_new (GPollFD, 1);
2312 poll_fd->events = events;
2313 poll_fd->revents = 0;
2315 context = source->context;
2318 LOCK_CONTEXT (context);
2320 source->priv->fds = g_slist_prepend (source->priv->fds, poll_fd);
2324 if (!SOURCE_BLOCKED (source))
2325 g_main_context_add_poll_unlocked (context, source->priority, poll_fd);
2326 UNLOCK_CONTEXT (context);
2333 * g_source_modify_unix_fd:
2334 * @source: a #GSource
2335 * @tag: the tag from g_source_add_unix_fd()
2336 * @new_events: the new event mask to watch
2338 * Updates the event mask to watch for the fd identified by @tag.
2340 * @tag is the tag returned from g_source_add_unix_fd().
2342 * If you want to remove a fd, don't set its event mask to zero.
2343 * Instead, call g_source_remove_unix_fd().
2345 * As the name suggests, this function is not available on Windows.
2350 g_source_modify_unix_fd (GSource *source,
2352 GIOCondition new_events)
2354 GMainContext *context;
2357 g_return_if_fail (source != NULL);
2358 g_return_if_fail (g_slist_find (source->priv->fds, tag));
2360 context = source->context;
2363 poll_fd->events = new_events;
2366 g_main_context_wakeup (context);
2370 * g_source_remove_unix_fd:
2371 * @source: a #GSource
2372 * @tag: the tag from g_source_add_unix_fd()
2374 * Reverses the effect of a previous call to g_source_add_unix_fd().
2376 * You only need to call this if you want to remove an fd from being
2377 * watched while keeping the same source around. In the normal case you
2378 * will just want to destroy the source.
2380 * As the name suggests, this function is not available on Windows.
2385 g_source_remove_unix_fd (GSource *source,
2388 GMainContext *context;
2391 g_return_if_fail (source != NULL);
2392 g_return_if_fail (g_slist_find (source->priv->fds, tag));
2394 context = source->context;
2398 LOCK_CONTEXT (context);
2400 source->priv->fds = g_slist_remove (source->priv->fds, poll_fd);
2404 if (!SOURCE_BLOCKED (source))
2405 g_main_context_remove_poll_unlocked (context, poll_fd);
2407 UNLOCK_CONTEXT (context);
2414 * g_source_query_unix_fd:
2415 * @source: a #GSource
2416 * @tag: the tag from g_source_add_unix_fd()
2418 * Queries the events reported for the fd corresponding to @tag on
2419 * @source during the last poll.
2421 * The return value of this function is only defined when the function
2422 * is called from the check or dispatch functions for @source.
2424 * As the name suggests, this function is not available on Windows.
2426 * Returns: the conditions reported on the fd
2431 g_source_query_unix_fd (GSource *source,
2436 g_return_val_if_fail (source != NULL, 0);
2437 g_return_val_if_fail (g_slist_find (source->priv->fds, tag), 0);
2441 return poll_fd->revents;
2443 #endif /* G_OS_UNIX */
2446 * g_get_current_time:
2447 * @result: #GTimeVal structure in which to store current time.
2449 * Equivalent to the UNIX gettimeofday() function, but portable.
2451 * You may find g_get_real_time() to be more convenient.
2454 g_get_current_time (GTimeVal *result)
2459 g_return_if_fail (result != NULL);
2461 /*this is required on alpha, there the timeval structs are int's
2462 not longs and a cast only would fail horribly*/
2463 gettimeofday (&r, NULL);
2464 result->tv_sec = r.tv_sec;
2465 result->tv_usec = r.tv_usec;
2470 g_return_if_fail (result != NULL);
2472 GetSystemTimeAsFileTime (&ft);
2473 memmove (&time64, &ft, sizeof (FILETIME));
2475 /* Convert from 100s of nanoseconds since 1601-01-01
2476 * to Unix epoch. Yes, this is Y2038 unsafe.
2478 time64 -= G_GINT64_CONSTANT (116444736000000000);
2481 result->tv_sec = time64 / 1000000;
2482 result->tv_usec = time64 % 1000000;
2489 * Queries the system wall-clock time.
2491 * This call is functionally equivalent to g_get_current_time() except
2492 * that the return value is often more convenient than dealing with a
2495 * You should only use this call if you are actually interested in the real
2496 * wall-clock time. g_get_monotonic_time() is probably more useful for
2497 * measuring intervals.
2499 * Returns: the number of microseconds since January 1, 1970 UTC.
2504 g_get_real_time (void)
2508 g_get_current_time (&tv);
2510 return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec;
2514 static ULONGLONG (*g_GetTickCount64) (void) = NULL;
2515 static guint32 g_win32_tick_epoch = 0;
2518 g_clock_win32_init (void)
2522 g_GetTickCount64 = NULL;
2523 kernel32 = GetModuleHandle ("KERNEL32.DLL");
2524 if (kernel32 != NULL)
2525 g_GetTickCount64 = (void *) GetProcAddress (kernel32, "GetTickCount64");
2526 g_win32_tick_epoch = ((guint32)GetTickCount()) >> 31;
2531 * g_get_monotonic_time:
2533 * Queries the system monotonic time, if available.
2535 * On POSIX systems with clock_gettime() and `CLOCK_MONOTONIC` this call
2536 * is a very shallow wrapper for that. Otherwise, we make a best effort
2537 * that probably involves returning the wall clock time (with at least
2538 * microsecond accuracy, subject to the limitations of the OS kernel).
2540 * It's important to note that POSIX `CLOCK_MONOTONIC` does
2541 * not count time spent while the machine is suspended.
2543 * On Windows, "limitations of the OS kernel" is a rather substantial
2544 * statement. Depending on the configuration of the system, the wall
2545 * clock time is updated as infrequently as 64 times a second (which
2546 * is approximately every 16ms). Also, on XP (but not on Vista or later)
2547 * the monotonic clock is locally monotonic, but may differ in exact
2548 * value between processes due to timer wrap handling.
2550 * Returns: the monotonic time, in microseconds
2555 g_get_monotonic_time (void)
2557 #ifdef HAVE_CLOCK_GETTIME
2558 /* librt clock_gettime() is our first choice */
2561 #ifdef CLOCK_MONOTONIC
2562 clock_gettime (CLOCK_MONOTONIC, &ts);
2564 clock_gettime (CLOCK_REALTIME, &ts);
2567 /* In theory monotonic time can have any epoch.
2569 * glib presently assumes the following:
2571 * 1) The epoch comes some time after the birth of Jesus of Nazareth, but
2572 * not more than 10000 years later.
2574 * 2) The current time also falls sometime within this range.
2576 * These two reasonable assumptions leave us with a maximum deviation from
2577 * the epoch of 10000 years, or 315569520000000000 seconds.
2579 * If we restrict ourselves to this range then the number of microseconds
2580 * will always fit well inside the constraints of a int64 (by a factor of
2583 * If you actually hit the following assertion, probably you should file a
2584 * bug against your operating system for being excessively silly.
2586 g_assert (G_GINT64_CONSTANT (-315569520000000000) < ts.tv_sec &&
2587 ts.tv_sec < G_GINT64_CONSTANT (315569520000000000));
2589 return (((gint64) ts.tv_sec) * 1000000) + (ts.tv_nsec / 1000);
2591 #elif defined (G_OS_WIN32)
2595 /* There are four sources for the monotonic time on Windows:
2597 * Three are based on a (1 msec accuracy, but only read periodically) clock chip:
2598 * - GetTickCount (GTC)
2599 * 32bit msec counter, updated each ~15msec, wraps in ~50 days
2600 * - GetTickCount64 (GTC64)
2601 * Same as GetTickCount, but extended to 64bit, so no wrap
2602 * Only available in Vista or later
2603 * - timeGetTime (TGT)
2604 * similar to GetTickCount by default: 15msec, 50 day wrap.
2605 * available in winmm.dll (thus known as the multimedia timers)
2606 * However apps can raise the system timer clock frequency using timeBeginPeriod()
2607 * increasing the accuracy up to 1 msec, at a cost in general system performance
2610 * One is based on high precision clocks:
2611 * - QueryPrecisionCounter (QPC)
2612 * This has much higher accuracy, but is not guaranteed monotonic, and
2613 * has lots of complications like clock jumps and different times on different
2614 * CPUs. It also has lower long term accuracy (i.e. it will drift compared to
2615 * the low precision clocks.
2617 * Additionally, the precision available in the timer-based wakeup such as
2618 * MsgWaitForMultipleObjectsEx (which is what the mainloop is based on) is based
2619 * on the TGT resolution, so by default it is ~15msec, but can be increased by apps.
2621 * The QPC timer has too many issues to be used as is. The only way it could be used
2622 * is to use it to interpolate the lower precision clocks. Firefox does something like
2624 * https://bugzilla.mozilla.org/show_bug.cgi?id=363258
2626 * However this seems quite complicated, so we're not doing this right now.
2628 * The approach we take instead is to use the TGT timer, extending it to 64bit
2629 * either by using the GTC64 value, or if that is not available, a process local
2630 * time epoch that we increment when we detect a timer wrap (assumes that we read
2631 * the time at least once every 50 days).
2634 * - We have a globally consistent monotonic clock on Vista and later
2635 * - We have a locally monotonic clock on XP
2636 * - Apps that need higher precision in timeouts and clock reads can call
2637 * timeBeginPeriod() to increase it as much as they want
2640 if (g_GetTickCount64 != NULL)
2642 guint32 ticks_as_32bit;
2644 ticks = g_GetTickCount64 ();
2645 ticks32 = timeGetTime();
2647 /* GTC64 and TGT are sampled at different times, however they
2648 * have the same base and source (msecs since system boot).
2649 * They can differ by as much as -16 to +16 msecs.
2650 * We can't just inject the low bits into the 64bit counter
2651 * as one of the counters can have wrapped in 32bit space and
2652 * the other not. Instead we calculate the signed difference
2653 * in 32bit space and apply that difference to the 64bit counter.
2655 ticks_as_32bit = (guint32)ticks;
2657 /* We could do some 2's complement hack, but we play it safe */
2658 if (ticks32 - ticks_as_32bit <= G_MAXINT32)
2659 ticks += ticks32 - ticks_as_32bit;
2661 ticks -= ticks_as_32bit - ticks32;
2667 epoch = g_atomic_int_get (&g_win32_tick_epoch);
2669 /* Must read ticks after the epoch. Then we're guaranteed
2670 * that the ticks value we read is higher or equal to any
2671 * previous ones that lead to the writing of the epoch.
2673 ticks32 = timeGetTime();
2675 /* We store the MSB of the current time as the LSB
2676 * of the epoch. Comparing these bits lets us detect when
2677 * the 32bit counter has wrapped so we can increase the
2680 * This will work as long as this function is called at
2681 * least once every ~24 days, which is half the wrap time
2682 * of a 32bit msec counter. I think this is pretty likely.
2684 * Note that g_win32_tick_epoch is a process local state,
2685 * so the monotonic clock will not be the same between
2688 if ((ticks32 >> 31) != (epoch & 1))
2691 g_atomic_int_set (&g_win32_tick_epoch, epoch);
2695 ticks = (guint64)ticks32 | ((guint64)epoch) << 31;
2698 return ticks * 1000;
2700 #else /* !HAVE_CLOCK_GETTIME && ! G_OS_WIN32*/
2704 g_get_current_time (&tv);
2706 return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec;
2711 g_main_dispatch_free (gpointer dispatch)
2713 g_slice_free (GMainDispatch, dispatch);
2716 /* Running the main loop */
2718 static GMainDispatch *
2721 static GPrivate depth_private = G_PRIVATE_INIT (g_main_dispatch_free);
2722 GMainDispatch *dispatch;
2724 dispatch = g_private_get (&depth_private);
2728 dispatch = g_slice_new0 (GMainDispatch);
2729 g_private_set (&depth_private, dispatch);
2738 * Returns the depth of the stack of calls to
2739 * g_main_context_dispatch() on any #GMainContext in the current thread.
2740 * That is, when called from the toplevel, it gives 0. When
2741 * called from within a callback from g_main_context_iteration()
2742 * (or g_main_loop_run(), etc.) it returns 1. When called from within
2743 * a callback to a recursive call to g_main_context_iteration(),
2744 * it returns 2. And so forth.
2746 * This function is useful in a situation like the following:
2747 * Imagine an extremely simple "garbage collected" system.
2749 * |[<!-- language="C" -->
2750 * static GList *free_list;
2753 * allocate_memory (gsize size)
2755 * gpointer result = g_malloc (size);
2756 * free_list = g_list_prepend (free_list, result);
2761 * free_allocated_memory (void)
2764 * for (l = free_list; l; l = l->next);
2766 * g_list_free (free_list);
2774 * g_main_context_iteration (NULL, TRUE);
2775 * free_allocated_memory();
2779 * This works from an application, however, if you want to do the same
2780 * thing from a library, it gets more difficult, since you no longer
2781 * control the main loop. You might think you can simply use an idle
2782 * function to make the call to free_allocated_memory(), but that
2783 * doesn't work, since the idle function could be called from a
2784 * recursive callback. This can be fixed by using g_main_depth()
2786 * |[<!-- language="C" -->
2788 * allocate_memory (gsize size)
2790 * FreeListBlock *block = g_new (FreeListBlock, 1);
2791 * block->mem = g_malloc (size);
2792 * block->depth = g_main_depth ();
2793 * free_list = g_list_prepend (free_list, block);
2794 * return block->mem;
2798 * free_allocated_memory (void)
2802 * int depth = g_main_depth ();
2803 * for (l = free_list; l; );
2805 * GList *next = l->next;
2806 * FreeListBlock *block = l->data;
2807 * if (block->depth > depth)
2809 * g_free (block->mem);
2811 * free_list = g_list_delete_link (free_list, l);
2819 * There is a temptation to use g_main_depth() to solve
2820 * problems with reentrancy. For instance, while waiting for data
2821 * to be received from the network in response to a menu item,
2822 * the menu item might be selected again. It might seem that
2823 * one could make the menu item's callback return immediately
2824 * and do nothing if g_main_depth() returns a value greater than 1.
2825 * However, this should be avoided since the user then sees selecting
2826 * the menu item do nothing. Furthermore, you'll find yourself adding
2827 * these checks all over your code, since there are doubtless many,
2828 * many things that the user could do. Instead, you can use the
2829 * following techniques:
2831 * 1. Use gtk_widget_set_sensitive() or modal dialogs to prevent
2832 * the user from interacting with elements while the main
2833 * loop is recursing.
2835 * 2. Avoid main loop recursion in situations where you can't handle
2836 * arbitrary callbacks. Instead, structure your code so that you
2837 * simply return to the main loop and then get called again when
2838 * there is more work to do.
2840 * Return value: The main loop recursion level in the current thread
2845 GMainDispatch *dispatch = get_dispatch ();
2846 return dispatch->depth;
2850 * g_main_current_source:
2852 * Returns the currently firing source for this thread.
2854 * Return value: (transfer none): The currently firing source or %NULL.
2859 g_main_current_source (void)
2861 GMainDispatch *dispatch = get_dispatch ();
2862 return dispatch->source;
2866 * g_source_is_destroyed:
2867 * @source: a #GSource
2869 * Returns whether @source has been destroyed.
2871 * This is important when you operate upon your objects
2872 * from within idle handlers, but may have freed the object
2873 * before the dispatch of your idle handler.
2875 * |[<!-- language="C" -->
2877 * idle_callback (gpointer data)
2879 * SomeWidget *self = data;
2881 * GDK_THREADS_ENTER ();
2882 * // do stuff with self
2883 * self->idle_id = 0;
2884 * GDK_THREADS_LEAVE ();
2886 * return G_SOURCE_REMOVE;
2890 * some_widget_do_stuff_later (SomeWidget *self)
2892 * self->idle_id = g_idle_add (idle_callback, self);
2896 * some_widget_finalize (GObject *object)
2898 * SomeWidget *self = SOME_WIDGET (object);
2900 * if (self->idle_id)
2901 * g_source_remove (self->idle_id);
2903 * G_OBJECT_CLASS (parent_class)->finalize (object);
2907 * This will fail in a multi-threaded application if the
2908 * widget is destroyed before the idle handler fires due
2909 * to the use after free in the callback. A solution, to
2910 * this particular problem, is to check to if the source
2911 * has already been destroy within the callback.
2913 * |[<!-- language="C" -->
2915 * idle_callback (gpointer data)
2917 * SomeWidget *self = data;
2919 * GDK_THREADS_ENTER ();
2920 * if (!g_source_is_destroyed (g_main_current_source ()))
2922 * // do stuff with self
2924 * GDK_THREADS_LEAVE ();
2930 * Return value: %TRUE if the source has been destroyed
2935 g_source_is_destroyed (GSource *source)
2937 return SOURCE_DESTROYED (source);
2940 /* Temporarily remove all this source's file descriptors from the
2941 * poll(), so that if data comes available for one of the file descriptors
2942 * we don't continually spin in the poll()
2944 /* HOLDS: source->context's lock */
2946 block_source (GSource *source)
2950 g_return_if_fail (!SOURCE_BLOCKED (source));
2952 source->flags |= G_SOURCE_BLOCKED;
2954 if (source->context)
2956 tmp_list = source->poll_fds;
2959 g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
2960 tmp_list = tmp_list->next;
2963 for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
2964 g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
2967 if (source->priv && source->priv->child_sources)
2969 tmp_list = source->priv->child_sources;
2972 block_source (tmp_list->data);
2973 tmp_list = tmp_list->next;
2978 /* HOLDS: source->context's lock */
2980 unblock_source (GSource *source)
2984 g_return_if_fail (SOURCE_BLOCKED (source)); /* Source already unblocked */
2985 g_return_if_fail (!SOURCE_DESTROYED (source));
2987 source->flags &= ~G_SOURCE_BLOCKED;
2989 tmp_list = source->poll_fds;
2992 g_main_context_add_poll_unlocked (source->context, source->priority, tmp_list->data);
2993 tmp_list = tmp_list->next;
2996 for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
2997 g_main_context_add_poll_unlocked (source->context, source->priority, tmp_list->data);
2999 if (source->priv && source->priv->child_sources)
3001 tmp_list = source->priv->child_sources;
3004 unblock_source (tmp_list->data);
3005 tmp_list = tmp_list->next;
3010 /* HOLDS: context's lock */
3012 g_main_dispatch (GMainContext *context)
3014 GMainDispatch *current = get_dispatch ();
3017 for (i = 0; i < context->pending_dispatches->len; i++)
3019 GSource *source = context->pending_dispatches->pdata[i];
3021 context->pending_dispatches->pdata[i] = NULL;
3024 source->flags &= ~G_SOURCE_READY;
3026 if (!SOURCE_DESTROYED (source))
3028 gboolean was_in_call;
3029 gpointer user_data = NULL;
3030 GSourceFunc callback = NULL;
3031 GSourceCallbackFuncs *cb_funcs;
3033 gboolean need_destroy;
3035 gboolean (*dispatch) (GSource *,
3038 GSource *prev_source;
3040 dispatch = source->source_funcs->dispatch;
3041 cb_funcs = source->callback_funcs;
3042 cb_data = source->callback_data;
3045 cb_funcs->ref (cb_data);
3047 if ((source->flags & G_SOURCE_CAN_RECURSE) == 0)
3048 block_source (source);
3050 was_in_call = source->flags & G_HOOK_FLAG_IN_CALL;
3051 source->flags |= G_HOOK_FLAG_IN_CALL;
3054 cb_funcs->get (cb_data, source, &callback, &user_data);
3056 UNLOCK_CONTEXT (context);
3058 /* These operations are safe because 'current' is thread-local
3059 * and not modified from anywhere but this function.
3061 prev_source = current->source;
3062 current->source = source;
3065 TRACE( GLIB_MAIN_BEFORE_DISPATCH (g_source_get_name (source)));
3066 need_destroy = !(* dispatch) (source, callback, user_data);
3067 TRACE( GLIB_MAIN_AFTER_DISPATCH (g_source_get_name (source)));
3069 current->source = prev_source;
3073 cb_funcs->unref (cb_data);
3075 LOCK_CONTEXT (context);
3078 source->flags &= ~G_HOOK_FLAG_IN_CALL;
3080 if (SOURCE_BLOCKED (source) && !SOURCE_DESTROYED (source))
3081 unblock_source (source);
3083 /* Note: this depends on the fact that we can't switch
3084 * sources from one main context to another
3086 if (need_destroy && !SOURCE_DESTROYED (source))
3088 g_assert (source->context == context);
3089 g_source_destroy_internal (source, context, TRUE);
3093 SOURCE_UNREF (source, context);
3096 g_ptr_array_set_size (context->pending_dispatches, 0);
3100 * g_main_context_acquire:
3101 * @context: a #GMainContext
3103 * Tries to become the owner of the specified context.
3104 * If some other thread is the owner of the context,
3105 * returns %FALSE immediately. Ownership is properly
3106 * recursive: the owner can require ownership again
3107 * and will release ownership when g_main_context_release()
3108 * is called as many times as g_main_context_acquire().
3110 * You must be the owner of a context before you
3111 * can call g_main_context_prepare(), g_main_context_query(),
3112 * g_main_context_check(), g_main_context_dispatch().
3114 * Return value: %TRUE if the operation succeeded, and
3115 * this thread is now the owner of @context.
3118 g_main_context_acquire (GMainContext *context)
3120 gboolean result = FALSE;
3121 GThread *self = G_THREAD_SELF;
3123 if (context == NULL)
3124 context = g_main_context_default ();
3126 LOCK_CONTEXT (context);
3128 if (!context->owner)
3130 context->owner = self;
3131 g_assert (context->owner_count == 0);
3134 if (context->owner == self)
3136 context->owner_count++;
3140 UNLOCK_CONTEXT (context);
3146 * g_main_context_release:
3147 * @context: a #GMainContext
3149 * Releases ownership of a context previously acquired by this thread
3150 * with g_main_context_acquire(). If the context was acquired multiple
3151 * times, the ownership will be released only when g_main_context_release()
3152 * is called as many times as it was acquired.
3155 g_main_context_release (GMainContext *context)
3157 if (context == NULL)
3158 context = g_main_context_default ();
3160 LOCK_CONTEXT (context);
3162 context->owner_count--;
3163 if (context->owner_count == 0)
3165 context->owner = NULL;
3167 if (context->waiters)
3169 GMainWaiter *waiter = context->waiters->data;
3170 gboolean loop_internal_waiter = (waiter->mutex == &context->mutex);
3171 context->waiters = g_slist_delete_link (context->waiters,
3173 if (!loop_internal_waiter)
3174 g_mutex_lock (waiter->mutex);
3176 g_cond_signal (waiter->cond);
3178 if (!loop_internal_waiter)
3179 g_mutex_unlock (waiter->mutex);
3183 UNLOCK_CONTEXT (context);
3187 * g_main_context_wait:
3188 * @context: a #GMainContext
3189 * @cond: a condition variable
3190 * @mutex: a mutex, currently held
3192 * Tries to become the owner of the specified context,
3193 * as with g_main_context_acquire(). But if another thread
3194 * is the owner, atomically drop @mutex and wait on @cond until
3195 * that owner releases ownership or until @cond is signaled, then
3196 * try again (once) to become the owner.
3198 * Return value: %TRUE if the operation succeeded, and
3199 * this thread is now the owner of @context.
3202 g_main_context_wait (GMainContext *context,
3206 gboolean result = FALSE;
3207 GThread *self = G_THREAD_SELF;
3208 gboolean loop_internal_waiter;
3210 if (context == NULL)
3211 context = g_main_context_default ();
3213 loop_internal_waiter = (mutex == &context->mutex);
3215 if (!loop_internal_waiter)
3216 LOCK_CONTEXT (context);
3218 if (context->owner && context->owner != self)
3223 waiter.mutex = mutex;
3225 context->waiters = g_slist_append (context->waiters, &waiter);
3227 if (!loop_internal_waiter)
3228 UNLOCK_CONTEXT (context);
3229 g_cond_wait (cond, mutex);
3230 if (!loop_internal_waiter)
3231 LOCK_CONTEXT (context);
3233 context->waiters = g_slist_remove (context->waiters, &waiter);
3236 if (!context->owner)
3238 context->owner = self;
3239 g_assert (context->owner_count == 0);
3242 if (context->owner == self)
3244 context->owner_count++;
3248 if (!loop_internal_waiter)
3249 UNLOCK_CONTEXT (context);
3255 * g_main_context_prepare:
3256 * @context: a #GMainContext
3257 * @priority: location to store priority of highest priority
3258 * source already ready.
3260 * Prepares to poll sources within a main loop. The resulting information
3261 * for polling is determined by calling g_main_context_query ().
3263 * Return value: %TRUE if some source is ready to be dispatched
3267 g_main_context_prepare (GMainContext *context,
3272 gint current_priority = G_MAXINT;
3276 if (context == NULL)
3277 context = g_main_context_default ();
3279 LOCK_CONTEXT (context);
3281 context->time_is_fresh = FALSE;
3283 if (context->in_check_or_prepare)
3285 g_warning ("g_main_context_prepare() called recursively from within a source's check() or "
3286 "prepare() member.");
3287 UNLOCK_CONTEXT (context);
3292 /* If recursing, finish up current dispatch, before starting over */
3293 if (context->pending_dispatches)
3296 g_main_dispatch (context, ¤t_time);
3298 UNLOCK_CONTEXT (context);
3303 /* If recursing, clear list of pending dispatches */
3305 for (i = 0; i < context->pending_dispatches->len; i++)
3307 if (context->pending_dispatches->pdata[i])
3308 SOURCE_UNREF ((GSource *)context->pending_dispatches->pdata[i], context);
3310 g_ptr_array_set_size (context->pending_dispatches, 0);
3312 /* Prepare all sources */
3314 context->timeout = -1;
3316 g_source_iter_init (&iter, context, TRUE);
3317 while (g_source_iter_next (&iter, &source))
3319 gint source_timeout = -1;
3321 if (SOURCE_DESTROYED (source) || SOURCE_BLOCKED (source))
3323 if ((n_ready > 0) && (source->priority > current_priority))
3326 if (!(source->flags & G_SOURCE_READY))
3329 gboolean (* prepare) (GSource *source,
3332 prepare = source->source_funcs->prepare;
3336 context->in_check_or_prepare++;
3337 UNLOCK_CONTEXT (context);
3339 result = (* prepare) (source, &source_timeout);
3341 LOCK_CONTEXT (context);
3342 context->in_check_or_prepare--;
3346 source_timeout = -1;
3350 if (result == FALSE && source->priv->ready_time != -1)
3352 if (!context->time_is_fresh)
3354 context->time = g_get_monotonic_time ();
3355 context->time_is_fresh = TRUE;
3358 if (source->priv->ready_time <= context->time)
3367 /* rounding down will lead to spinning, so always round up */
3368 timeout = (source->priv->ready_time - context->time + 999) / 1000;
3370 if (source_timeout < 0 || timeout < source_timeout)
3371 source_timeout = timeout;
3377 GSource *ready_source = source;
3379 while (ready_source)
3381 ready_source->flags |= G_SOURCE_READY;
3382 ready_source = ready_source->priv->parent_source;
3387 if (source->flags & G_SOURCE_READY)
3390 current_priority = source->priority;
3391 context->timeout = 0;
3394 if (source_timeout >= 0)
3396 if (context->timeout < 0)
3397 context->timeout = source_timeout;
3399 context->timeout = MIN (context->timeout, source_timeout);
3402 g_source_iter_clear (&iter);
3404 UNLOCK_CONTEXT (context);
3407 *priority = current_priority;
3409 return (n_ready > 0);
3413 * g_main_context_query:
3414 * @context: a #GMainContext
3415 * @max_priority: maximum priority source to check
3416 * @timeout_: (out): location to store timeout to be used in polling
3417 * @fds: (out caller-allocates) (array length=n_fds): location to
3418 * store #GPollFD records that need to be polled.
3419 * @n_fds: length of @fds.
3421 * Determines information necessary to poll this main loop.
3423 * Return value: the number of records actually stored in @fds,
3424 * or, if more than @n_fds records need to be stored, the number
3425 * of records that need to be stored.
3428 g_main_context_query (GMainContext *context,
3437 LOCK_CONTEXT (context);
3439 pollrec = context->poll_records;
3441 while (pollrec && max_priority >= pollrec->priority)
3443 /* We need to include entries with fd->events == 0 in the array because
3444 * otherwise if the application changes fd->events behind our back and
3445 * makes it non-zero, we'll be out of sync when we check the fds[] array.
3446 * (Changing fd->events after adding an FD wasn't an anticipated use of
3447 * this API, but it occurs in practice.) */
3450 fds[n_poll].fd = pollrec->fd->fd;
3451 /* In direct contradiction to the Unix98 spec, IRIX runs into
3452 * difficulty if you pass in POLLERR, POLLHUP or POLLNVAL
3453 * flags in the events field of the pollfd while it should
3454 * just ignoring them. So we mask them out here.
3456 fds[n_poll].events = pollrec->fd->events & ~(G_IO_ERR|G_IO_HUP|G_IO_NVAL);
3457 fds[n_poll].revents = 0;
3460 pollrec = pollrec->next;
3464 context->poll_changed = FALSE;
3468 *timeout = context->timeout;
3470 context->time_is_fresh = FALSE;
3473 UNLOCK_CONTEXT (context);
3479 * g_main_context_check:
3480 * @context: a #GMainContext
3481 * @max_priority: the maximum numerical priority of sources to check
3482 * @fds: (array length=n_fds): array of #GPollFD's that was passed to
3483 * the last call to g_main_context_query()
3484 * @n_fds: return value of g_main_context_query()
3486 * Passes the results of polling back to the main loop.
3488 * Return value: %TRUE if some sources are ready to be dispatched.
3491 g_main_context_check (GMainContext *context,
3502 LOCK_CONTEXT (context);
3504 if (context->in_check_or_prepare)
3506 g_warning ("g_main_context_check() called recursively from within a source's check() or "
3507 "prepare() member.");
3508 UNLOCK_CONTEXT (context);
3512 if (context->wake_up_rec.revents)
3513 g_wakeup_acknowledge (context->wakeup);
3515 /* If the set of poll file descriptors changed, bail out
3516 * and let the main loop rerun
3518 if (context->poll_changed)
3520 UNLOCK_CONTEXT (context);
3524 pollrec = context->poll_records;
3528 if (pollrec->fd->events)
3529 pollrec->fd->revents = fds[i].revents;
3531 pollrec = pollrec->next;
3535 g_source_iter_init (&iter, context, TRUE);
3536 while (g_source_iter_next (&iter, &source))
3538 if (SOURCE_DESTROYED (source) || SOURCE_BLOCKED (source))
3540 if ((n_ready > 0) && (source->priority > max_priority))
3543 if (!(source->flags & G_SOURCE_READY))
3546 gboolean (* check) (GSource *source);
3548 check = source->source_funcs->check;
3552 /* If the check function is set, call it. */
3553 context->in_check_or_prepare++;
3554 UNLOCK_CONTEXT (context);
3556 result = (* check) (source);
3558 LOCK_CONTEXT (context);
3559 context->in_check_or_prepare--;
3564 if (result == FALSE)
3568 /* If not already explicitly flagged ready by ->check()
3569 * (or if we have no check) then we can still be ready if
3570 * any of our fds poll as ready.
3572 for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
3574 GPollFD *pollfd = tmp_list->data;
3576 if (pollfd->revents)
3584 if (result == FALSE && source->priv->ready_time != -1)
3586 if (!context->time_is_fresh)
3588 context->time = g_get_monotonic_time ();
3589 context->time_is_fresh = TRUE;
3592 if (source->priv->ready_time <= context->time)
3598 GSource *ready_source = source;
3600 while (ready_source)
3602 ready_source->flags |= G_SOURCE_READY;
3603 ready_source = ready_source->priv->parent_source;
3608 if (source->flags & G_SOURCE_READY)
3610 source->ref_count++;
3611 g_ptr_array_add (context->pending_dispatches, source);
3615 /* never dispatch sources with less priority than the first
3616 * one we choose to dispatch
3618 max_priority = source->priority;
3621 g_source_iter_clear (&iter);
3623 UNLOCK_CONTEXT (context);
3629 * g_main_context_dispatch:
3630 * @context: a #GMainContext
3632 * Dispatches all pending sources.
3635 g_main_context_dispatch (GMainContext *context)
3637 LOCK_CONTEXT (context);
3639 if (context->pending_dispatches->len > 0)
3641 g_main_dispatch (context);
3644 UNLOCK_CONTEXT (context);
3647 /* HOLDS context lock */
3649 g_main_context_iterate (GMainContext *context,
3656 gboolean some_ready;
3657 gint nfds, allocated_nfds;
3658 GPollFD *fds = NULL;
3660 UNLOCK_CONTEXT (context);
3662 if (!g_main_context_acquire (context))
3664 gboolean got_ownership;
3666 LOCK_CONTEXT (context);
3671 got_ownership = g_main_context_wait (context,
3679 LOCK_CONTEXT (context);
3681 if (!context->cached_poll_array)
3683 context->cached_poll_array_size = context->n_poll_records;
3684 context->cached_poll_array = g_new (GPollFD, context->n_poll_records);
3687 allocated_nfds = context->cached_poll_array_size;
3688 fds = context->cached_poll_array;
3690 UNLOCK_CONTEXT (context);
3692 g_main_context_prepare (context, &max_priority);
3694 while ((nfds = g_main_context_query (context, max_priority, &timeout, fds,
3695 allocated_nfds)) > allocated_nfds)
3697 LOCK_CONTEXT (context);
3699 context->cached_poll_array_size = allocated_nfds = nfds;
3700 context->cached_poll_array = fds = g_new (GPollFD, nfds);
3701 UNLOCK_CONTEXT (context);
3707 g_main_context_poll (context, timeout, max_priority, fds, nfds);
3709 some_ready = g_main_context_check (context, max_priority, fds, nfds);
3712 g_main_context_dispatch (context);
3714 g_main_context_release (context);
3716 LOCK_CONTEXT (context);
3722 * g_main_context_pending:
3723 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
3725 * Checks if any sources have pending events for the given context.
3727 * Return value: %TRUE if events are pending.
3730 g_main_context_pending (GMainContext *context)
3735 context = g_main_context_default();
3737 LOCK_CONTEXT (context);
3738 retval = g_main_context_iterate (context, FALSE, FALSE, G_THREAD_SELF);
3739 UNLOCK_CONTEXT (context);
3745 * g_main_context_iteration:
3746 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
3747 * @may_block: whether the call may block.
3749 * Runs a single iteration for the given main loop. This involves
3750 * checking to see if any event sources are ready to be processed,
3751 * then if no events sources are ready and @may_block is %TRUE, waiting
3752 * for a source to become ready, then dispatching the highest priority
3753 * events sources that are ready. Otherwise, if @may_block is %FALSE
3754 * sources are not waited to become ready, only those highest priority
3755 * events sources will be dispatched (if any), that are ready at this
3756 * given moment without further waiting.
3758 * Note that even when @may_block is %TRUE, it is still possible for
3759 * g_main_context_iteration() to return %FALSE, since the wait may
3760 * be interrupted for other reasons than an event source becoming ready.
3762 * Return value: %TRUE if events were dispatched.
3765 g_main_context_iteration (GMainContext *context, gboolean may_block)
3770 context = g_main_context_default();
3772 LOCK_CONTEXT (context);
3773 retval = g_main_context_iterate (context, may_block, TRUE, G_THREAD_SELF);
3774 UNLOCK_CONTEXT (context);
3781 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used).
3782 * @is_running: set to %TRUE to indicate that the loop is running. This
3783 * is not very important since calling g_main_loop_run() will set this to
3786 * Creates a new #GMainLoop structure.
3788 * Return value: a new #GMainLoop.
3791 g_main_loop_new (GMainContext *context,
3792 gboolean is_running)
3797 context = g_main_context_default();
3799 g_main_context_ref (context);
3801 loop = g_new0 (GMainLoop, 1);
3802 loop->context = context;
3803 loop->is_running = is_running != FALSE;
3804 loop->ref_count = 1;
3811 * @loop: a #GMainLoop
3813 * Increases the reference count on a #GMainLoop object by one.
3815 * Return value: @loop
3818 g_main_loop_ref (GMainLoop *loop)
3820 g_return_val_if_fail (loop != NULL, NULL);
3821 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
3823 g_atomic_int_inc (&loop->ref_count);
3829 * g_main_loop_unref:
3830 * @loop: a #GMainLoop
3832 * Decreases the reference count on a #GMainLoop object by one. If
3833 * the result is zero, free the loop and free all associated memory.
3836 g_main_loop_unref (GMainLoop *loop)
3838 g_return_if_fail (loop != NULL);
3839 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3841 if (!g_atomic_int_dec_and_test (&loop->ref_count))
3844 g_main_context_unref (loop->context);
3850 * @loop: a #GMainLoop
3852 * Runs a main loop until g_main_loop_quit() is called on the loop.
3853 * If this is called for the thread of the loop's #GMainContext,
3854 * it will process events from the loop, otherwise it will
3858 g_main_loop_run (GMainLoop *loop)
3860 GThread *self = G_THREAD_SELF;
3862 g_return_if_fail (loop != NULL);
3863 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3865 if (!g_main_context_acquire (loop->context))
3867 gboolean got_ownership = FALSE;
3869 /* Another thread owns this context */
3870 LOCK_CONTEXT (loop->context);
3872 g_atomic_int_inc (&loop->ref_count);
3874 if (!loop->is_running)
3875 loop->is_running = TRUE;
3877 while (loop->is_running && !got_ownership)
3878 got_ownership = g_main_context_wait (loop->context,
3879 &loop->context->cond,
3880 &loop->context->mutex);
3882 if (!loop->is_running)
3884 UNLOCK_CONTEXT (loop->context);
3886 g_main_context_release (loop->context);
3887 g_main_loop_unref (loop);
3891 g_assert (got_ownership);
3894 LOCK_CONTEXT (loop->context);
3896 if (loop->context->in_check_or_prepare)
3898 g_warning ("g_main_loop_run(): called recursively from within a source's "
3899 "check() or prepare() member, iteration not possible.");
3903 g_atomic_int_inc (&loop->ref_count);
3904 loop->is_running = TRUE;
3905 while (loop->is_running)
3906 g_main_context_iterate (loop->context, TRUE, TRUE, self);
3908 UNLOCK_CONTEXT (loop->context);
3910 g_main_context_release (loop->context);
3912 g_main_loop_unref (loop);
3917 * @loop: a #GMainLoop
3919 * Stops a #GMainLoop from running. Any calls to g_main_loop_run()
3920 * for the loop will return.
3922 * Note that sources that have already been dispatched when
3923 * g_main_loop_quit() is called will still be executed.
3926 g_main_loop_quit (GMainLoop *loop)
3928 g_return_if_fail (loop != NULL);
3929 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3931 LOCK_CONTEXT (loop->context);
3932 loop->is_running = FALSE;
3933 g_wakeup_signal (loop->context->wakeup);
3935 g_cond_broadcast (&loop->context->cond);
3937 UNLOCK_CONTEXT (loop->context);
3941 * g_main_loop_is_running:
3942 * @loop: a #GMainLoop.
3944 * Checks to see if the main loop is currently being run via g_main_loop_run().
3946 * Return value: %TRUE if the mainloop is currently being run.
3949 g_main_loop_is_running (GMainLoop *loop)
3951 g_return_val_if_fail (loop != NULL, FALSE);
3952 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, FALSE);
3954 return loop->is_running;
3958 * g_main_loop_get_context:
3959 * @loop: a #GMainLoop.
3961 * Returns the #GMainContext of @loop.
3963 * Return value: (transfer none): the #GMainContext of @loop
3966 g_main_loop_get_context (GMainLoop *loop)
3968 g_return_val_if_fail (loop != NULL, NULL);
3969 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
3971 return loop->context;
3974 /* HOLDS: context's lock */
3976 g_main_context_poll (GMainContext *context,
3982 #ifdef G_MAIN_POLL_DEBUG
3988 GPollFunc poll_func;
3990 if (n_fds || timeout != 0)
3992 #ifdef G_MAIN_POLL_DEBUG
3993 if (_g_main_poll_debug)
3995 g_print ("polling context=%p n=%d timeout=%d\n",
3996 context, n_fds, timeout);
3997 poll_timer = g_timer_new ();
4001 LOCK_CONTEXT (context);
4003 poll_func = context->poll_func;
4005 UNLOCK_CONTEXT (context);
4006 if ((*poll_func) (fds, n_fds, timeout) < 0 && errno != EINTR)
4009 g_warning ("poll(2) failed due to: %s.",
4010 g_strerror (errno));
4012 /* If g_poll () returns -1, it has already called g_warning() */
4016 #ifdef G_MAIN_POLL_DEBUG
4017 if (_g_main_poll_debug)
4019 LOCK_CONTEXT (context);
4021 g_print ("g_main_poll(%d) timeout: %d - elapsed %12.10f seconds",
4024 g_timer_elapsed (poll_timer, NULL));
4025 g_timer_destroy (poll_timer);
4026 pollrec = context->poll_records;
4028 while (pollrec != NULL)
4033 if (fds[i].fd == pollrec->fd->fd &&
4034 pollrec->fd->events &&
4037 g_print (" [" G_POLLFD_FORMAT " :", fds[i].fd);
4038 if (fds[i].revents & G_IO_IN)
4040 if (fds[i].revents & G_IO_OUT)
4042 if (fds[i].revents & G_IO_PRI)
4044 if (fds[i].revents & G_IO_ERR)
4046 if (fds[i].revents & G_IO_HUP)
4048 if (fds[i].revents & G_IO_NVAL)
4054 pollrec = pollrec->next;
4058 UNLOCK_CONTEXT (context);
4061 } /* if (n_fds || timeout != 0) */
4065 * g_main_context_add_poll:
4066 * @context: (allow-none): a #GMainContext (or %NULL for the default context)
4067 * @fd: a #GPollFD structure holding information about a file
4068 * descriptor to watch.
4069 * @priority: the priority for this file descriptor which should be
4070 * the same as the priority used for g_source_attach() to ensure that the
4071 * file descriptor is polled whenever the results may be needed.
4073 * Adds a file descriptor to the set of file descriptors polled for
4074 * this context. This will very seldom be used directly. Instead
4075 * a typical event source will use g_source_add_unix_fd() instead.
4078 g_main_context_add_poll (GMainContext *context,
4083 context = g_main_context_default ();
4085 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
4086 g_return_if_fail (fd);
4088 LOCK_CONTEXT (context);
4089 g_main_context_add_poll_unlocked (context, priority, fd);
4090 UNLOCK_CONTEXT (context);
4093 /* HOLDS: main_loop_lock */
4095 g_main_context_add_poll_unlocked (GMainContext *context,
4099 GPollRec *prevrec, *nextrec;
4100 GPollRec *newrec = g_slice_new (GPollRec);
4102 /* This file descriptor may be checked before we ever poll */
4105 newrec->priority = priority;
4107 prevrec = context->poll_records_tail;
4109 while (prevrec && priority < prevrec->priority)
4112 prevrec = prevrec->prev;
4116 prevrec->next = newrec;
4118 context->poll_records = newrec;
4120 newrec->prev = prevrec;
4121 newrec->next = nextrec;
4124 nextrec->prev = newrec;
4126 context->poll_records_tail = newrec;
4128 context->n_poll_records++;
4130 context->poll_changed = TRUE;
4132 /* Now wake up the main loop if it is waiting in the poll() */
4133 g_wakeup_signal (context->wakeup);
4137 * g_main_context_remove_poll:
4138 * @context:a #GMainContext
4139 * @fd: a #GPollFD descriptor previously added with g_main_context_add_poll()
4141 * Removes file descriptor from the set of file descriptors to be
4142 * polled for a particular context.
4145 g_main_context_remove_poll (GMainContext *context,
4149 context = g_main_context_default ();
4151 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
4152 g_return_if_fail (fd);
4154 LOCK_CONTEXT (context);
4155 g_main_context_remove_poll_unlocked (context, fd);
4156 UNLOCK_CONTEXT (context);
4160 g_main_context_remove_poll_unlocked (GMainContext *context,
4163 GPollRec *pollrec, *prevrec, *nextrec;
4166 pollrec = context->poll_records;
4170 nextrec = pollrec->next;
4171 if (pollrec->fd == fd)
4173 if (prevrec != NULL)
4174 prevrec->next = nextrec;
4176 context->poll_records = nextrec;
4178 if (nextrec != NULL)
4179 nextrec->prev = prevrec;
4181 context->poll_records_tail = prevrec;
4183 g_slice_free (GPollRec, pollrec);
4185 context->n_poll_records--;
4192 context->poll_changed = TRUE;
4194 /* Now wake up the main loop if it is waiting in the poll() */
4195 g_wakeup_signal (context->wakeup);
4199 * g_source_get_current_time:
4200 * @source: a #GSource
4201 * @timeval: #GTimeVal structure in which to store current time.
4203 * This function ignores @source and is otherwise the same as
4204 * g_get_current_time().
4206 * Deprecated: 2.28: use g_source_get_time() instead
4209 g_source_get_current_time (GSource *source,
4212 g_get_current_time (timeval);
4216 * g_source_get_time:
4217 * @source: a #GSource
4219 * Gets the time to be used when checking this source. The advantage of
4220 * calling this function over calling g_get_monotonic_time() directly is
4221 * that when checking multiple sources, GLib can cache a single value
4222 * instead of having to repeatedly get the system monotonic time.
4224 * The time here is the system monotonic time, if available, or some
4225 * other reasonable alternative otherwise. See g_get_monotonic_time().
4227 * Returns: the monotonic time in microseconds
4232 g_source_get_time (GSource *source)
4234 GMainContext *context;
4237 g_return_val_if_fail (source->context != NULL, 0);
4239 context = source->context;
4241 LOCK_CONTEXT (context);
4243 if (!context->time_is_fresh)
4245 context->time = g_get_monotonic_time ();
4246 context->time_is_fresh = TRUE;
4249 result = context->time;
4251 UNLOCK_CONTEXT (context);
4257 * g_main_context_set_poll_func:
4258 * @context: a #GMainContext
4259 * @func: the function to call to poll all file descriptors
4261 * Sets the function to use to handle polling of file descriptors. It
4262 * will be used instead of the poll() system call
4263 * (or GLib's replacement function, which is used where
4264 * poll() isn't available).
4266 * This function could possibly be used to integrate the GLib event
4267 * loop with an external event loop.
4270 g_main_context_set_poll_func (GMainContext *context,
4274 context = g_main_context_default ();
4276 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
4278 LOCK_CONTEXT (context);
4281 context->poll_func = func;
4283 context->poll_func = g_poll;
4285 UNLOCK_CONTEXT (context);
4289 * g_main_context_get_poll_func:
4290 * @context: a #GMainContext
4292 * Gets the poll function set by g_main_context_set_poll_func().
4294 * Return value: the poll function
4297 g_main_context_get_poll_func (GMainContext *context)
4302 context = g_main_context_default ();
4304 g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL);
4306 LOCK_CONTEXT (context);
4307 result = context->poll_func;
4308 UNLOCK_CONTEXT (context);
4314 * g_main_context_wakeup:
4315 * @context: a #GMainContext
4317 * If @context is currently blocking in g_main_context_iteration()
4318 * waiting for a source to become ready, cause it to stop blocking
4319 * and return. Otherwise, cause the next invocation of
4320 * g_main_context_iteration() to return without blocking.
4322 * This API is useful for low-level control over #GMainContext; for
4323 * example, integrating it with main loop implementations such as
4326 * Another related use for this function is when implementing a main
4327 * loop with a termination condition, computed from multiple threads:
4329 * |[<!-- language="C" -->
4330 * #define NUM_TASKS 10
4331 * static volatile gint tasks_remaining = NUM_TASKS;
4334 * while (g_atomic_int_get (&tasks_remaining) != 0)
4335 * g_main_context_iteration (NULL, TRUE);
4339 * |[<!-- language="C" -->
4342 * if (g_atomic_int_dec_and_test (&tasks_remaining))
4343 * g_main_context_wakeup (NULL);
4347 g_main_context_wakeup (GMainContext *context)
4350 context = g_main_context_default ();
4352 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
4354 g_wakeup_signal (context->wakeup);
4358 * g_main_context_is_owner:
4359 * @context: a #GMainContext
4361 * Determines whether this thread holds the (recursive)
4362 * ownership of this #GMainContext. This is useful to
4363 * know before waiting on another thread that may be
4364 * blocking to get ownership of @context.
4366 * Returns: %TRUE if current thread is owner of @context.
4371 g_main_context_is_owner (GMainContext *context)
4376 context = g_main_context_default ();
4378 LOCK_CONTEXT (context);
4379 is_owner = context->owner == G_THREAD_SELF;
4380 UNLOCK_CONTEXT (context);
4388 g_timeout_set_expiration (GTimeoutSource *timeout_source,
4389 gint64 current_time)
4393 expiration = current_time + (guint64) timeout_source->interval * 1000;
4395 if (timeout_source->seconds)
4398 static gint timer_perturb = -1;
4400 if (timer_perturb == -1)
4403 * we want a per machine/session unique 'random' value; try the dbus
4404 * address first, that has a UUID in it. If there is no dbus, use the
4405 * hostname for hashing.
4407 const char *session_bus_address = g_getenv ("DBUS_SESSION_BUS_ADDRESS");
4408 if (!session_bus_address)
4409 session_bus_address = g_getenv ("HOSTNAME");
4410 if (session_bus_address)
4411 timer_perturb = ABS ((gint) g_str_hash (session_bus_address)) % 1000000;
4416 /* We want the microseconds part of the timeout to land on the
4417 * 'timer_perturb' mark, but we need to make sure we don't try to
4418 * set the timeout in the past. We do this by ensuring that we
4419 * always only *increase* the expiration time by adding a full
4420 * second in the case that the microsecond portion decreases.
4422 expiration -= timer_perturb;
4424 remainder = expiration % 1000000;
4425 if (remainder >= 1000000/4)
4426 expiration += 1000000;
4428 expiration -= remainder;
4429 expiration += timer_perturb;
4432 g_source_set_ready_time ((GSource *) timeout_source, expiration);
4436 g_timeout_dispatch (GSource *source,
4437 GSourceFunc callback,
4440 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
4445 g_warning ("Timeout source dispatched without callback\n"
4446 "You must call g_source_set_callback().");
4450 again = callback (user_data);
4453 g_timeout_set_expiration (timeout_source, g_source_get_time (source));
4459 * g_timeout_source_new:
4460 * @interval: the timeout interval in milliseconds.
4462 * Creates a new timeout source.
4464 * The source will not initially be associated with any #GMainContext
4465 * and must be added to one with g_source_attach() before it will be
4468 * The interval given is in terms of monotonic time, not wall clock
4469 * time. See g_get_monotonic_time().
4471 * Return value: the newly-created timeout source
4474 g_timeout_source_new (guint interval)
4476 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
4477 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
4479 timeout_source->interval = interval;
4480 g_timeout_set_expiration (timeout_source, g_get_monotonic_time ());
4486 * g_timeout_source_new_seconds:
4487 * @interval: the timeout interval in seconds
4489 * Creates a new timeout source.
4491 * The source will not initially be associated with any #GMainContext
4492 * and must be added to one with g_source_attach() before it will be
4495 * The scheduling granularity/accuracy of this timeout source will be
4498 * The interval given in terms of monotonic time, not wall clock time.
4499 * See g_get_monotonic_time().
4501 * Return value: the newly-created timeout source
4506 g_timeout_source_new_seconds (guint interval)
4508 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
4509 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
4511 timeout_source->interval = 1000 * interval;
4512 timeout_source->seconds = TRUE;
4514 g_timeout_set_expiration (timeout_source, g_get_monotonic_time ());
4521 * g_timeout_add_full:
4522 * @priority: the priority of the timeout source. Typically this will be in
4523 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
4524 * @interval: the time between calls to the function, in milliseconds
4525 * (1/1000ths of a second)
4526 * @function: function to call
4527 * @data: data to pass to @function
4528 * @notify: (allow-none): function to call when the timeout is removed, or %NULL
4530 * Sets a function to be called at regular intervals, with the given
4531 * priority. The function is called repeatedly until it returns
4532 * %FALSE, at which point the timeout is automatically destroyed and
4533 * the function will not be called again. The @notify function is
4534 * called when the timeout is destroyed. The first call to the
4535 * function will be at the end of the first @interval.
4537 * Note that timeout functions may be delayed, due to the processing of other
4538 * event sources. Thus they should not be relied on for precise timing.
4539 * After each call to the timeout function, the time of the next
4540 * timeout is recalculated based on the current time and the given interval
4541 * (it does not try to 'catch up' time lost in delays).
4543 * This internally creates a main loop source using g_timeout_source_new()
4544 * and attaches it to the main loop context using g_source_attach(). You can
4545 * do these steps manually if you need greater control.
4547 * The interval given in terms of monotonic time, not wall clock time.
4548 * See g_get_monotonic_time().
4550 * Return value: the ID (greater than 0) of the event source.
4551 * Rename to: g_timeout_add
4554 g_timeout_add_full (gint priority,
4556 GSourceFunc function,
4558 GDestroyNotify notify)
4563 g_return_val_if_fail (function != NULL, 0);
4565 source = g_timeout_source_new (interval);
4567 if (priority != G_PRIORITY_DEFAULT)
4568 g_source_set_priority (source, priority);
4570 g_source_set_callback (source, function, data, notify);
4571 id = g_source_attach (source, NULL);
4572 g_source_unref (source);
4579 * @interval: the time between calls to the function, in milliseconds
4580 * (1/1000ths of a second)
4581 * @function: function to call
4582 * @data: data to pass to @function
4584 * Sets a function to be called at regular intervals, with the default
4585 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly
4586 * until it returns %FALSE, at which point the timeout is automatically
4587 * destroyed and the function will not be called again. The first call
4588 * to the function will be at the end of the first @interval.
4590 * Note that timeout functions may be delayed, due to the processing of other
4591 * event sources. Thus they should not be relied on for precise timing.
4592 * After each call to the timeout function, the time of the next
4593 * timeout is recalculated based on the current time and the given interval
4594 * (it does not try to 'catch up' time lost in delays).
4596 * If you want to have a timer in the "seconds" range and do not care
4597 * about the exact time of the first call of the timer, use the
4598 * g_timeout_add_seconds() function; this function allows for more
4599 * optimizations and more efficient system power usage.
4601 * This internally creates a main loop source using g_timeout_source_new()
4602 * and attaches it to the main loop context using g_source_attach(). You can
4603 * do these steps manually if you need greater control.
4605 * The interval given is in terms of monotonic time, not wall clock
4606 * time. See g_get_monotonic_time().
4608 * Return value: the ID (greater than 0) of the event source.
4611 g_timeout_add (guint32 interval,
4612 GSourceFunc function,
4615 return g_timeout_add_full (G_PRIORITY_DEFAULT,
4616 interval, function, data, NULL);
4620 * g_timeout_add_seconds_full:
4621 * @priority: the priority of the timeout source. Typically this will be in
4622 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
4623 * @interval: the time between calls to the function, in seconds
4624 * @function: function to call
4625 * @data: data to pass to @function
4626 * @notify: (allow-none): function to call when the timeout is removed, or %NULL
4628 * Sets a function to be called at regular intervals, with @priority.
4629 * The function is called repeatedly until it returns %FALSE, at which
4630 * point the timeout is automatically destroyed and the function will
4631 * not be called again.
4633 * Unlike g_timeout_add(), this function operates at whole second granularity.
4634 * The initial starting point of the timer is determined by the implementation
4635 * and the implementation is expected to group multiple timers together so that
4636 * they fire all at the same time.
4637 * To allow this grouping, the @interval to the first timer is rounded
4638 * and can deviate up to one second from the specified interval.
4639 * Subsequent timer iterations will generally run at the specified interval.
4641 * Note that timeout functions may be delayed, due to the processing of other
4642 * event sources. Thus they should not be relied on for precise timing.
4643 * After each call to the timeout function, the time of the next
4644 * timeout is recalculated based on the current time and the given @interval
4646 * If you want timing more precise than whole seconds, use g_timeout_add()
4649 * The grouping of timers to fire at the same time results in a more power
4650 * and CPU efficient behavior so if your timer is in multiples of seconds
4651 * and you don't require the first timer exactly one second from now, the
4652 * use of g_timeout_add_seconds() is preferred over g_timeout_add().
4654 * This internally creates a main loop source using
4655 * g_timeout_source_new_seconds() and attaches it to the main loop context
4656 * using g_source_attach(). You can do these steps manually if you need
4659 * The interval given is in terms of monotonic time, not wall clock
4660 * time. See g_get_monotonic_time().
4662 * Return value: the ID (greater than 0) of the event source.
4664 * Rename to: g_timeout_add_seconds
4668 g_timeout_add_seconds_full (gint priority,
4670 GSourceFunc function,
4672 GDestroyNotify notify)
4677 g_return_val_if_fail (function != NULL, 0);
4679 source = g_timeout_source_new_seconds (interval);
4681 if (priority != G_PRIORITY_DEFAULT)
4682 g_source_set_priority (source, priority);
4684 g_source_set_callback (source, function, data, notify);
4685 id = g_source_attach (source, NULL);
4686 g_source_unref (source);
4692 * g_timeout_add_seconds:
4693 * @interval: the time between calls to the function, in seconds
4694 * @function: function to call
4695 * @data: data to pass to @function
4697 * Sets a function to be called at regular intervals with the default
4698 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly until
4699 * it returns %FALSE, at which point the timeout is automatically destroyed
4700 * and the function will not be called again.
4702 * This internally creates a main loop source using
4703 * g_timeout_source_new_seconds() and attaches it to the main loop context
4704 * using g_source_attach(). You can do these steps manually if you need
4705 * greater control. Also see g_timeout_add_seconds_full().
4707 * Note that the first call of the timer may not be precise for timeouts
4708 * of one second. If you need finer precision and have such a timeout,
4709 * you may want to use g_timeout_add() instead.
4711 * The interval given is in terms of monotonic time, not wall clock
4712 * time. See g_get_monotonic_time().
4714 * Return value: the ID (greater than 0) of the event source.
4719 g_timeout_add_seconds (guint interval,
4720 GSourceFunc function,
4723 g_return_val_if_fail (function != NULL, 0);
4725 return g_timeout_add_seconds_full (G_PRIORITY_DEFAULT, interval, function, data, NULL);
4728 /* Child watch functions */
4733 g_child_watch_prepare (GSource *source,
4741 g_child_watch_check (GSource *source)
4743 GChildWatchSource *child_watch_source;
4744 gboolean child_exited;
4746 child_watch_source = (GChildWatchSource *) source;
4748 child_exited = child_watch_source->poll.revents & G_IO_IN;
4755 * Note: We do _not_ check for the special value of STILL_ACTIVE
4756 * since we know that the process has exited and doing so runs into
4757 * problems if the child process "happens to return STILL_ACTIVE(259)"
4758 * as Microsoft's Platform SDK puts it.
4760 if (!GetExitCodeProcess (child_watch_source->pid, &child_status))
4762 gchar *emsg = g_win32_error_message (GetLastError ());
4763 g_warning (G_STRLOC ": GetExitCodeProcess() failed: %s", emsg);
4766 child_watch_source->child_status = -1;
4769 child_watch_source->child_status = child_status;
4772 return child_exited;
4776 g_child_watch_finalize (GSource *source)
4780 #else /* G_OS_WIN32 */
4783 wake_source (GSource *source)
4785 GMainContext *context;
4787 /* This should be thread-safe:
4789 * - if the source is currently being added to a context, that
4790 * context will be woken up anyway
4792 * - if the source is currently being destroyed, we simply need not
4795 * - the memory for the source will remain valid until after the
4796 * source finalize function was called (which would remove the
4797 * source from the global list which we are currently holding the
4800 * - the GMainContext will either be NULL or point to a live
4803 * - the GMainContext will remain valid since we hold the
4804 * main_context_list lock
4806 * Since we are holding a lot of locks here, don't try to enter any
4807 * more GMainContext functions for fear of dealock -- just hit the
4808 * GWakeup and run. Even if that's safe now, it could easily become
4809 * unsafe with some very minor changes in the future, and signal
4810 * handling is not the most well-tested codepath.
4812 G_LOCK(main_context_list);
4813 context = source->context;
4815 g_wakeup_signal (context->wakeup);
4816 G_UNLOCK(main_context_list);
4820 dispatch_unix_signals_unlocked (void)
4822 gboolean pending[NSIG];
4826 /* clear this first incase another one arrives while we're processing */
4827 any_unix_signal_pending = FALSE;
4829 /* We atomically test/clear the bit from the global array in case
4830 * other signals arrive while we are dispatching.
4832 * We then can safely use our own array below without worrying about
4835 for (i = 0; i < NSIG; i++)
4837 /* Be very careful with (the volatile) unix_signal_pending.
4839 * We must ensure that it's not possible that we clear it without
4840 * handling the signal. We therefore must ensure that our pending
4841 * array has a field set (ie: we will do something about the
4842 * signal) before we clear the item in unix_signal_pending.
4844 * Note specifically: we must check _our_ array.
4846 pending[i] = unix_signal_pending[i];
4848 unix_signal_pending[i] = FALSE;
4851 /* handle GChildWatchSource instances */
4852 if (pending[SIGCHLD])
4854 /* The only way we can do this is to scan all of the children.
4856 * The docs promise that we will not reap children that we are not
4857 * explicitly watching, so that ties our hands from calling
4858 * waitpid(-1). We also can't use siginfo's si_pid field since if
4859 * multiple SIGCHLD arrive at the same time, one of them can be
4860 * dropped (since a given UNIX signal can only be pending once).
4862 for (node = unix_child_watches; node; node = node->next)
4864 GChildWatchSource *source = node->data;
4866 if (!source->child_exited)
4871 g_assert (source->pid > 0);
4873 pid = waitpid (source->pid, &source->child_status, WNOHANG);
4876 source->child_exited = TRUE;
4877 wake_source ((GSource *) source);
4879 else if (pid == -1 && errno == ECHILD)
4881 g_warning ("GChildWatchSource: Exit status of a child process was requested but ECHILD was received by waitpid(). Most likely the process is ignoring SIGCHLD, or some other thread is invoking waitpid() with a nonpositive first argument; either behavior can break applications that use g_child_watch_add()/g_spawn_sync() either directly or indirectly.");
4882 source->child_exited = TRUE;
4883 source->child_status = 0;
4884 wake_source ((GSource *) source);
4887 while (pid == -1 && errno == EINTR);
4892 /* handle GUnixSignalWatchSource instances */
4893 for (node = unix_signal_watches; node; node = node->next)
4895 GUnixSignalWatchSource *source = node->data;
4897 if (!source->pending)
4899 if (pending[source->signum])
4901 source->pending = TRUE;
4903 wake_source ((GSource *) source);
4911 dispatch_unix_signals (void)
4913 G_LOCK(unix_signal_lock);
4914 dispatch_unix_signals_unlocked ();
4915 G_UNLOCK(unix_signal_lock);
4919 g_child_watch_prepare (GSource *source,
4922 GChildWatchSource *child_watch_source;
4924 child_watch_source = (GChildWatchSource *) source;
4926 return child_watch_source->child_exited;
4930 g_child_watch_check (GSource *source)
4932 GChildWatchSource *child_watch_source;
4934 child_watch_source = (GChildWatchSource *) source;
4936 return child_watch_source->child_exited;
4940 g_unix_signal_watch_prepare (GSource *source,
4943 GUnixSignalWatchSource *unix_signal_source;
4945 unix_signal_source = (GUnixSignalWatchSource *) source;
4947 return unix_signal_source->pending;
4951 g_unix_signal_watch_check (GSource *source)
4953 GUnixSignalWatchSource *unix_signal_source;
4955 unix_signal_source = (GUnixSignalWatchSource *) source;
4957 return unix_signal_source->pending;
4961 g_unix_signal_watch_dispatch (GSource *source,
4962 GSourceFunc callback,
4965 GUnixSignalWatchSource *unix_signal_source;
4968 unix_signal_source = (GUnixSignalWatchSource *) source;
4972 g_warning ("Unix signal source dispatched without callback\n"
4973 "You must call g_source_set_callback().");
4977 again = (callback) (user_data);
4979 unix_signal_source->pending = FALSE;
4985 ref_unix_signal_handler_unlocked (int signum)
4987 /* Ensure we have the worker context */
4988 g_get_worker_context ();
4989 unix_signal_refcount[signum]++;
4990 if (unix_signal_refcount[signum] == 1)
4992 struct sigaction action;
4993 action.sa_handler = g_unix_signal_handler;
4994 sigemptyset (&action.sa_mask);
4996 action.sa_flags = SA_RESTART | SA_NOCLDSTOP;
4998 action.sa_flags = SA_NOCLDSTOP;
5000 sigaction (signum, &action, NULL);
5005 unref_unix_signal_handler_unlocked (int signum)
5007 unix_signal_refcount[signum]--;
5008 if (unix_signal_refcount[signum] == 0)
5010 struct sigaction action;
5011 memset (&action, 0, sizeof (action));
5012 action.sa_handler = SIG_DFL;
5013 sigemptyset (&action.sa_mask);
5014 sigaction (signum, &action, NULL);
5019 _g_main_create_unix_signal_watch (int signum)
5022 GUnixSignalWatchSource *unix_signal_source;
5024 source = g_source_new (&g_unix_signal_funcs, sizeof (GUnixSignalWatchSource));
5025 unix_signal_source = (GUnixSignalWatchSource *) source;
5027 unix_signal_source->signum = signum;
5028 unix_signal_source->pending = FALSE;
5030 G_LOCK (unix_signal_lock);
5031 ref_unix_signal_handler_unlocked (signum);
5032 unix_signal_watches = g_slist_prepend (unix_signal_watches, unix_signal_source);
5033 dispatch_unix_signals_unlocked ();
5034 G_UNLOCK (unix_signal_lock);
5040 g_unix_signal_watch_finalize (GSource *source)
5042 GUnixSignalWatchSource *unix_signal_source;
5044 unix_signal_source = (GUnixSignalWatchSource *) source;
5046 G_LOCK (unix_signal_lock);
5047 unref_unix_signal_handler_unlocked (unix_signal_source->signum);
5048 unix_signal_watches = g_slist_remove (unix_signal_watches, source);
5049 G_UNLOCK (unix_signal_lock);
5053 g_child_watch_finalize (GSource *source)
5055 G_LOCK (unix_signal_lock);
5056 unix_child_watches = g_slist_remove (unix_child_watches, source);
5057 unref_unix_signal_handler_unlocked (SIGCHLD);
5058 G_UNLOCK (unix_signal_lock);
5061 #endif /* G_OS_WIN32 */
5064 g_child_watch_dispatch (GSource *source,
5065 GSourceFunc callback,
5068 GChildWatchSource *child_watch_source;
5069 GChildWatchFunc child_watch_callback = (GChildWatchFunc) callback;
5071 child_watch_source = (GChildWatchSource *) source;
5075 g_warning ("Child watch source dispatched without callback\n"
5076 "You must call g_source_set_callback().");
5080 (child_watch_callback) (child_watch_source->pid, child_watch_source->child_status, user_data);
5082 /* We never keep a child watch source around as the child is gone */
5089 g_unix_signal_handler (int signum)
5091 unix_signal_pending[signum] = TRUE;
5092 any_unix_signal_pending = TRUE;
5094 g_wakeup_signal (glib_worker_context->wakeup);
5097 #endif /* !G_OS_WIN32 */
5100 * g_child_watch_source_new:
5101 * @pid: process to watch. On POSIX the positive pid of a child process. On
5102 * Windows a handle for a process (which doesn't have to be a child).
5104 * Creates a new child_watch source.
5106 * The source will not initially be associated with any #GMainContext
5107 * and must be added to one with g_source_attach() before it will be
5110 * Note that child watch sources can only be used in conjunction with
5111 * `g_spawn...` when the %G_SPAWN_DO_NOT_REAP_CHILD flag is used.
5113 * Note that on platforms where #GPid must be explicitly closed
5114 * (see g_spawn_close_pid()) @pid must not be closed while the
5115 * source is still active. Typically, you will want to call
5116 * g_spawn_close_pid() in the callback function for the source.
5118 * Note further that using g_child_watch_source_new() is not
5119 * compatible with calling `waitpid` with a nonpositive first
5120 * argument in the application. Calling waitpid() for individual
5121 * pids will still work fine.
5123 * Similarly, on POSIX platforms, the @pid passed to this function must
5124 * be greater than 0 (i.e. this function must wait for a specific child,
5125 * and cannot wait for one of many children by using a nonpositive argument).
5127 * Return value: the newly-created child watch source
5132 g_child_watch_source_new (GPid pid)
5135 GChildWatchSource *child_watch_source;
5138 g_return_val_if_fail (pid > 0, NULL);
5141 source = g_source_new (&g_child_watch_funcs, sizeof (GChildWatchSource));
5142 child_watch_source = (GChildWatchSource *)source;
5144 child_watch_source->pid = pid;
5147 child_watch_source->poll.fd = (gintptr) pid;
5148 child_watch_source->poll.events = G_IO_IN;
5150 g_source_add_poll (source, &child_watch_source->poll);
5151 #else /* G_OS_WIN32 */
5152 G_LOCK (unix_signal_lock);
5153 ref_unix_signal_handler_unlocked (SIGCHLD);
5154 unix_child_watches = g_slist_prepend (unix_child_watches, child_watch_source);
5155 if (waitpid (pid, &child_watch_source->child_status, WNOHANG) > 0)
5156 child_watch_source->child_exited = TRUE;
5157 G_UNLOCK (unix_signal_lock);
5158 #endif /* G_OS_WIN32 */
5164 * g_child_watch_add_full:
5165 * @priority: the priority of the idle source. Typically this will be in the
5166 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
5167 * @pid: process to watch. On POSIX the positive pid of a child process. On
5168 * Windows a handle for a process (which doesn't have to be a child).
5169 * @function: function to call
5170 * @data: data to pass to @function
5171 * @notify: (allow-none): function to call when the idle is removed, or %NULL
5173 * Sets a function to be called when the child indicated by @pid
5174 * exits, at the priority @priority.
5176 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
5177 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
5178 * the spawn function for the child watching to work.
5180 * In many programs, you will want to call g_spawn_check_exit_status()
5181 * in the callback to determine whether or not the child exited
5184 * Also, note that on platforms where #GPid must be explicitly closed
5185 * (see g_spawn_close_pid()) @pid must not be closed while the source
5186 * is still active. Typically, you should invoke g_spawn_close_pid()
5187 * in the callback function for the source.
5189 * GLib supports only a single callback per process id.
5191 * This internally creates a main loop source using
5192 * g_child_watch_source_new() and attaches it to the main loop context
5193 * using g_source_attach(). You can do these steps manually if you
5194 * need greater control.
5196 * Return value: the ID (greater than 0) of the event source.
5198 * Rename to: g_child_watch_add
5202 g_child_watch_add_full (gint priority,
5204 GChildWatchFunc function,
5206 GDestroyNotify notify)
5211 g_return_val_if_fail (function != NULL, 0);
5213 g_return_val_if_fail (pid > 0, 0);
5216 source = g_child_watch_source_new (pid);
5218 if (priority != G_PRIORITY_DEFAULT)
5219 g_source_set_priority (source, priority);
5221 g_source_set_callback (source, (GSourceFunc) function, data, notify);
5222 id = g_source_attach (source, NULL);
5223 g_source_unref (source);
5229 * g_child_watch_add:
5230 * @pid: process id to watch. On POSIX the positive pid of a child
5231 * process. On Windows a handle for a process (which doesn't have to be
5233 * @function: function to call
5234 * @data: data to pass to @function
5236 * Sets a function to be called when the child indicated by @pid
5237 * exits, at a default priority, #G_PRIORITY_DEFAULT.
5239 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
5240 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
5241 * the spawn function for the child watching to work.
5243 * Note that on platforms where #GPid must be explicitly closed
5244 * (see g_spawn_close_pid()) @pid must not be closed while the
5245 * source is still active. Typically, you will want to call
5246 * g_spawn_close_pid() in the callback function for the source.
5248 * GLib supports only a single callback per process id.
5250 * This internally creates a main loop source using
5251 * g_child_watch_source_new() and attaches it to the main loop context
5252 * using g_source_attach(). You can do these steps manually if you
5253 * need greater control.
5255 * Return value: the ID (greater than 0) of the event source.
5260 g_child_watch_add (GPid pid,
5261 GChildWatchFunc function,
5264 return g_child_watch_add_full (G_PRIORITY_DEFAULT, pid, function, data, NULL);
5268 /* Idle functions */
5271 g_idle_prepare (GSource *source,
5280 g_idle_check (GSource *source)
5286 g_idle_dispatch (GSource *source,
5287 GSourceFunc callback,
5292 g_warning ("Idle source dispatched without callback\n"
5293 "You must call g_source_set_callback().");
5297 return callback (user_data);
5301 * g_idle_source_new:
5303 * Creates a new idle source.
5305 * The source will not initially be associated with any #GMainContext
5306 * and must be added to one with g_source_attach() before it will be
5307 * executed. Note that the default priority for idle sources is
5308 * %G_PRIORITY_DEFAULT_IDLE, as compared to other sources which
5309 * have a default priority of %G_PRIORITY_DEFAULT.
5311 * Return value: the newly-created idle source
5314 g_idle_source_new (void)
5318 source = g_source_new (&g_idle_funcs, sizeof (GSource));
5319 g_source_set_priority (source, G_PRIORITY_DEFAULT_IDLE);
5326 * @priority: the priority of the idle source. Typically this will be in the
5327 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
5328 * @function: function to call
5329 * @data: data to pass to @function
5330 * @notify: (allow-none): function to call when the idle is removed, or %NULL
5332 * Adds a function to be called whenever there are no higher priority
5333 * events pending. If the function returns %FALSE it is automatically
5334 * removed from the list of event sources and will not be called again.
5336 * This internally creates a main loop source using g_idle_source_new()
5337 * and attaches it to the main loop context using g_source_attach().
5338 * You can do these steps manually if you need greater control.
5340 * Return value: the ID (greater than 0) of the event source.
5341 * Rename to: g_idle_add
5344 g_idle_add_full (gint priority,
5345 GSourceFunc function,
5347 GDestroyNotify notify)
5352 g_return_val_if_fail (function != NULL, 0);
5354 source = g_idle_source_new ();
5356 if (priority != G_PRIORITY_DEFAULT_IDLE)
5357 g_source_set_priority (source, priority);
5359 g_source_set_callback (source, function, data, notify);
5360 id = g_source_attach (source, NULL);
5361 g_source_unref (source);
5368 * @function: function to call
5369 * @data: data to pass to @function.
5371 * Adds a function to be called whenever there are no higher priority
5372 * events pending to the default main loop. The function is given the
5373 * default idle priority, #G_PRIORITY_DEFAULT_IDLE. If the function
5374 * returns %FALSE it is automatically removed from the list of event
5375 * sources and will not be called again.
5377 * This internally creates a main loop source using g_idle_source_new()
5378 * and attaches it to the main loop context using g_source_attach().
5379 * You can do these steps manually if you need greater control.
5381 * Return value: the ID (greater than 0) of the event source.
5384 g_idle_add (GSourceFunc function,
5387 return g_idle_add_full (G_PRIORITY_DEFAULT_IDLE, function, data, NULL);
5391 * g_idle_remove_by_data:
5392 * @data: the data for the idle source's callback.
5394 * Removes the idle function with the given data.
5396 * Return value: %TRUE if an idle source was found and removed.
5399 g_idle_remove_by_data (gpointer data)
5401 return g_source_remove_by_funcs_user_data (&g_idle_funcs, data);
5405 * g_main_context_invoke:
5406 * @context: (allow-none): a #GMainContext, or %NULL
5407 * @function: function to call
5408 * @data: data to pass to @function
5410 * Invokes a function in such a way that @context is owned during the
5411 * invocation of @function.
5413 * If @context is %NULL then the global default main context — as
5414 * returned by g_main_context_default() — is used.
5416 * If @context is owned by the current thread, @function is called
5417 * directly. Otherwise, if @context is the thread-default main context
5418 * of the current thread and g_main_context_acquire() succeeds, then
5419 * @function is called and g_main_context_release() is called
5422 * In any other case, an idle source is created to call @function and
5423 * that source is attached to @context (presumably to be run in another
5424 * thread). The idle source is attached with #G_PRIORITY_DEFAULT
5425 * priority. If you want a different priority, use
5426 * g_main_context_invoke_full().
5428 * Note that, as with normal idle functions, @function should probably
5429 * return %FALSE. If it returns %TRUE, it will be continuously run in a
5430 * loop (and may prevent this call from returning).
5435 g_main_context_invoke (GMainContext *context,
5436 GSourceFunc function,
5439 g_main_context_invoke_full (context,
5441 function, data, NULL);
5445 * g_main_context_invoke_full:
5446 * @context: (allow-none): a #GMainContext, or %NULL
5447 * @priority: the priority at which to run @function
5448 * @function: function to call
5449 * @data: data to pass to @function
5450 * @notify: (allow-none): a function to call when @data is no longer in use, or %NULL.
5452 * Invokes a function in such a way that @context is owned during the
5453 * invocation of @function.
5455 * This function is the same as g_main_context_invoke() except that it
5456 * lets you specify the priority incase @function ends up being
5457 * scheduled as an idle and also lets you give a #GDestroyNotify for @data.
5459 * @notify should not assume that it is called from any particular
5460 * thread or with any particular context acquired.
5465 g_main_context_invoke_full (GMainContext *context,
5467 GSourceFunc function,
5469 GDestroyNotify notify)
5471 g_return_if_fail (function != NULL);
5474 context = g_main_context_default ();
5476 if (g_main_context_is_owner (context))
5478 while (function (data));
5485 GMainContext *thread_default;
5487 thread_default = g_main_context_get_thread_default ();
5489 if (!thread_default)
5490 thread_default = g_main_context_default ();
5492 if (thread_default == context && g_main_context_acquire (context))
5494 while (function (data));
5496 g_main_context_release (context);
5505 source = g_idle_source_new ();
5506 g_source_set_priority (source, priority);
5507 g_source_set_callback (source, function, data, notify);
5508 g_source_attach (source, context);
5509 g_source_unref (source);
5515 glib_worker_main (gpointer data)
5519 g_main_context_iteration (glib_worker_context, TRUE);
5522 if (any_unix_signal_pending)
5523 dispatch_unix_signals ();
5527 return NULL; /* worst GCC warning message ever... */
5531 g_get_worker_context (void)
5533 static gsize initialised;
5535 if (g_once_init_enter (&initialised))
5537 /* mask all signals in the worker thread */
5543 pthread_sigmask (SIG_SETMASK, &all, &prev_mask);
5545 glib_worker_context = g_main_context_new ();
5546 g_thread_new ("gmain", glib_worker_main, NULL);
5548 pthread_sigmask (SIG_SETMASK, &prev_mask, NULL);
5550 g_once_init_leave (&initialised, TRUE);
5553 return glib_worker_context;