1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * gmain.c: Main loop abstraction, timeouts, and idle functions
5 * Copyright 1998 Owen Taylor
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
24 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
25 * file for a list of people on the GLib Team. See the ChangeLog
26 * files for a list of changes. These files are distributed with
27 * GLib at ftp://ftp.gtk.org/pub/gtk/.
35 #include "glibconfig.h"
37 /* Uncomment the next line (and the corresponding line in gpoll.c) to
38 * enable debugging printouts if the environment variable
39 * G_MAIN_POLL_DEBUG is set to some value.
41 /* #define G_MAIN_POLL_DEBUG */
44 /* Always enable debugging printout on Windows, as it is more often
47 #define G_MAIN_POLL_DEBUG
51 #include "glib-unix.h"
54 #include <sys/eventfd.h>
59 #include <sys/types.h>
62 #ifdef HAVE_SYS_TIME_H
64 #endif /* HAVE_SYS_TIME_H */
67 #endif /* HAVE_UNISTD_H */
74 #endif /* G_OS_WIN32 */
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 * <refsect2><title>Creating new source types</title>
140 * <para>One of the unusual features of the #GMainLoop functionality
141 * is that new types of event source can be created and used in
142 * addition to the builtin type of event source. A new event source
143 * type is used for handling GDK events. A new source type is created
144 * by <firstterm>deriving</firstterm> from the #GSource structure.
145 * The derived type of source is represented by a structure that has
146 * the #GSource structure as a first element, and other elements specific
147 * to the new source type. To create an instance of the new source type,
148 * call g_source_new() passing in the size of the derived structure and
149 * a table of functions. These #GSourceFuncs determine the behavior of
150 * the new source type.</para>
151 * <para>New source types basically interact with the main context
152 * in two ways. Their prepare function in #GSourceFuncs can set a timeout
153 * to determine the maximum amount of time that the main loop will sleep
154 * before checking the source again. In addition, or as well, the source
155 * can add file descriptors to the set that the main context checks using
156 * g_source_add_poll().</para>
158 * <refsect2><title>Customizing the main loop iteration</title>
159 * <para>Single iterations of a #GMainContext can be run with
160 * g_main_context_iteration(). In some cases, more detailed control
161 * of exactly how the details of the main loop work is desired, for
162 * instance, when integrating the #GMainLoop with an external main loop.
163 * In such cases, you can call the component functions of
164 * g_main_context_iteration() directly. These functions are
165 * g_main_context_prepare(), g_main_context_query(),
166 * g_main_context_check() and g_main_context_dispatch().</para>
167 * <para>The operation of these functions can best be seen in terms
168 * of a state diagram, as shown in <xref linkend="mainloop-states"/>.</para>
169 * <figure id="mainloop-states"><title>States of a Main Context</title>
170 * <graphic fileref="mainloop-states.gif" format="GIF"></graphic>
174 * On Unix, the GLib mainloop is incompatible with fork(). Any program
175 * using the mainloop must either exec() or exit() from the child
176 * without returning to the mainloop.
181 typedef struct _GTimeoutSource GTimeoutSource;
182 typedef struct _GChildWatchSource GChildWatchSource;
183 typedef struct _GUnixSignalWatchSource GUnixSignalWatchSource;
184 typedef struct _GPollRec GPollRec;
185 typedef struct _GSourceCallback GSourceCallback;
189 G_SOURCE_READY = 1 << G_HOOK_FLAG_USER_SHIFT,
190 G_SOURCE_CAN_RECURSE = 1 << (G_HOOK_FLAG_USER_SHIFT + 1),
191 G_SOURCE_BLOCKED = 1 << (G_HOOK_FLAG_USER_SHIFT + 2)
194 typedef struct _GSourceList GSourceList;
198 GSource *head, *tail;
202 typedef struct _GMainWaiter GMainWaiter;
210 typedef struct _GMainDispatch GMainDispatch;
212 struct _GMainDispatch
218 #ifdef G_MAIN_POLL_DEBUG
219 gboolean _g_main_poll_debug = FALSE;
224 /* The following lock is used for both the list of sources
225 * and the list of poll records
235 GPtrArray *pending_dispatches;
236 gint timeout; /* Timeout for current iteration */
239 GHashTable *overflow_used_source_ids; /* set<guint> */
241 gint in_check_or_prepare;
243 GPollRec *poll_records, *poll_records_tail;
244 guint n_poll_records;
245 GPollFD *cached_poll_array;
246 guint cached_poll_array_size;
252 /* Flag indicating whether the set of fd's changed during a poll */
253 gboolean poll_changed;
258 gboolean time_is_fresh;
261 struct _GSourceCallback
266 GDestroyNotify notify;
271 GMainContext *context;
276 struct _GTimeoutSource
283 struct _GChildWatchSource
290 #else /* G_OS_WIN32 */
291 gboolean child_exited;
292 #endif /* G_OS_WIN32 */
295 struct _GUnixSignalWatchSource
310 struct _GSourcePrivate
312 GSList *child_sources;
313 GSource *parent_source;
317 /* This is currently only used on UNIX, but we always declare it (and
318 * let it remain empty on Windows) to avoid #ifdef all over the place.
323 typedef struct _GSourceIter
325 GMainContext *context;
331 #define LOCK_CONTEXT(context) g_mutex_lock (&context->mutex)
332 #define UNLOCK_CONTEXT(context) g_mutex_unlock (&context->mutex)
333 #define G_THREAD_SELF g_thread_self ()
335 #define SOURCE_DESTROYED(source) (((source)->flags & G_HOOK_FLAG_ACTIVE) == 0)
336 #define SOURCE_BLOCKED(source) (((source)->flags & G_SOURCE_BLOCKED) != 0)
338 #define SOURCE_UNREF(source, context) \
340 if ((source)->ref_count > 1) \
341 (source)->ref_count--; \
343 g_source_unref_internal ((source), (context), TRUE); \
347 /* Forward declarations */
349 static void g_source_unref_internal (GSource *source,
350 GMainContext *context,
352 static void g_source_destroy_internal (GSource *source,
353 GMainContext *context,
355 static void g_source_set_priority_unlocked (GSource *source,
356 GMainContext *context,
358 static void g_child_source_remove_internal (GSource *child_source,
359 GMainContext *context);
361 static void g_main_context_poll (GMainContext *context,
366 static void g_main_context_add_poll_unlocked (GMainContext *context,
369 static void g_main_context_remove_poll_unlocked (GMainContext *context,
372 static void g_source_iter_init (GSourceIter *iter,
373 GMainContext *context,
374 gboolean may_modify);
375 static gboolean g_source_iter_next (GSourceIter *iter,
377 static void g_source_iter_clear (GSourceIter *iter);
379 static gboolean g_timeout_dispatch (GSource *source,
380 GSourceFunc callback,
382 static gboolean g_child_watch_prepare (GSource *source,
384 static gboolean g_child_watch_check (GSource *source);
385 static gboolean g_child_watch_dispatch (GSource *source,
386 GSourceFunc callback,
388 static void g_child_watch_finalize (GSource *source);
390 static void g_unix_signal_handler (int signum);
391 static gboolean g_unix_signal_watch_prepare (GSource *source,
393 static gboolean g_unix_signal_watch_check (GSource *source);
394 static gboolean g_unix_signal_watch_dispatch (GSource *source,
395 GSourceFunc callback,
397 static void g_unix_signal_watch_finalize (GSource *source);
399 static gboolean g_idle_prepare (GSource *source,
401 static gboolean g_idle_check (GSource *source);
402 static gboolean g_idle_dispatch (GSource *source,
403 GSourceFunc callback,
406 static void block_source (GSource *source);
408 static GMainContext *glib_worker_context;
410 G_LOCK_DEFINE_STATIC (main_loop);
411 static GMainContext *default_main_context;
416 /* UNIX signals work by marking one of these variables then waking the
417 * worker context to check on them and dispatch accordingly.
419 #ifdef HAVE_SIG_ATOMIC_T
420 static volatile sig_atomic_t unix_signal_pending[NSIG];
421 static volatile sig_atomic_t any_unix_signal_pending;
423 static volatile int unix_signal_pending[NSIG];
424 static volatile int any_unix_signal_pending;
426 static volatile guint unix_signal_refcount[NSIG];
428 /* Guards all the data below */
429 G_LOCK_DEFINE_STATIC (unix_signal_lock);
430 static GSList *unix_signal_watches;
431 static GSList *unix_child_watches;
433 GSourceFuncs g_unix_signal_funcs =
435 g_unix_signal_watch_prepare,
436 g_unix_signal_watch_check,
437 g_unix_signal_watch_dispatch,
438 g_unix_signal_watch_finalize
440 #endif /* !G_OS_WIN32 */
441 G_LOCK_DEFINE_STATIC (main_context_list);
442 static GSList *main_context_list = NULL;
444 GSourceFuncs g_timeout_funcs =
452 GSourceFuncs g_child_watch_funcs =
454 g_child_watch_prepare,
456 g_child_watch_dispatch,
457 g_child_watch_finalize
460 GSourceFuncs g_idle_funcs =
469 * g_main_context_ref:
470 * @context: a #GMainContext
472 * Increases the reference count on a #GMainContext object by one.
474 * Returns: the @context that was passed in (since 2.6)
477 g_main_context_ref (GMainContext *context)
479 g_return_val_if_fail (context != NULL, NULL);
480 g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL);
482 g_atomic_int_inc (&context->ref_count);
488 poll_rec_list_free (GMainContext *context,
491 g_slice_free_chain (GPollRec, list, next);
495 * g_main_context_unref:
496 * @context: a #GMainContext
498 * Decreases the reference count on a #GMainContext object by one. If
499 * the result is zero, free the context and free all associated memory.
502 g_main_context_unref (GMainContext *context)
509 g_return_if_fail (context != NULL);
510 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
512 if (!g_atomic_int_dec_and_test (&context->ref_count))
515 G_LOCK (main_context_list);
516 main_context_list = g_slist_remove (main_context_list, context);
517 G_UNLOCK (main_context_list);
519 /* g_source_iter_next() assumes the context is locked. */
520 LOCK_CONTEXT (context);
521 g_source_iter_init (&iter, context, TRUE);
522 while (g_source_iter_next (&iter, &source))
524 source->context = NULL;
525 g_source_destroy_internal (source, context, TRUE);
527 UNLOCK_CONTEXT (context);
529 for (sl_iter = context->source_lists; sl_iter; sl_iter = sl_iter->next)
531 list = sl_iter->data;
532 g_slice_free (GSourceList, list);
534 g_list_free (context->source_lists);
536 if (context->overflow_used_source_ids)
537 g_hash_table_destroy (context->overflow_used_source_ids);
539 g_mutex_clear (&context->mutex);
541 g_ptr_array_free (context->pending_dispatches, TRUE);
542 g_free (context->cached_poll_array);
544 poll_rec_list_free (context, context->poll_records);
546 g_wakeup_free (context->wakeup);
547 g_cond_clear (&context->cond);
552 /* Helper function used by mainloop/overflow test.
555 g_main_context_new_with_next_id (guint next_id)
557 GMainContext *ret = g_main_context_new ();
559 ret->next_id = next_id;
565 * g_main_context_new:
567 * Creates a new #GMainContext structure.
569 * Return value: the new #GMainContext
572 g_main_context_new (void)
574 static gsize initialised;
575 GMainContext *context;
577 if (g_once_init_enter (&initialised))
579 #ifdef G_MAIN_POLL_DEBUG
580 if (getenv ("G_MAIN_POLL_DEBUG") != NULL)
581 _g_main_poll_debug = TRUE;
584 g_once_init_leave (&initialised, TRUE);
587 context = g_new0 (GMainContext, 1);
589 g_mutex_init (&context->mutex);
590 g_cond_init (&context->cond);
592 context->owner = NULL;
593 context->waiters = NULL;
595 context->ref_count = 1;
597 context->next_id = 1;
599 context->source_lists = NULL;
601 context->poll_func = g_poll;
603 context->cached_poll_array = NULL;
604 context->cached_poll_array_size = 0;
606 context->pending_dispatches = g_ptr_array_new ();
608 context->time_is_fresh = FALSE;
610 context->wakeup = g_wakeup_new ();
611 g_wakeup_get_pollfd (context->wakeup, &context->wake_up_rec);
612 g_main_context_add_poll_unlocked (context, 0, &context->wake_up_rec);
614 G_LOCK (main_context_list);
615 main_context_list = g_slist_append (main_context_list, context);
617 #ifdef G_MAIN_POLL_DEBUG
618 if (_g_main_poll_debug)
619 g_print ("created context=%p\n", context);
622 G_UNLOCK (main_context_list);
628 * g_main_context_default:
630 * Returns the global default main context. This is the main context
631 * used for main loop functions when a main loop is not explicitly
632 * specified, and corresponds to the "main" main loop. See also
633 * g_main_context_get_thread_default().
635 * Return value: (transfer none): the global default main context.
638 g_main_context_default (void)
644 if (!default_main_context)
646 default_main_context = g_main_context_new ();
647 #ifdef G_MAIN_POLL_DEBUG
648 if (_g_main_poll_debug)
649 g_print ("default context=%p\n", default_main_context);
653 G_UNLOCK (main_loop);
655 return default_main_context;
659 free_context (gpointer data)
661 GMainContext *context = data;
663 g_main_context_release (context);
665 g_main_context_unref (context);
669 free_context_stack (gpointer data)
671 g_queue_free_full((GQueue *) data, (GDestroyNotify) free_context);
674 static GPrivate thread_context_stack = G_PRIVATE_INIT (free_context_stack);
677 * g_main_context_push_thread_default:
678 * @context: (allow-none): a #GMainContext, or %NULL for the global default context
680 * Acquires @context and sets it as the thread-default context for the
681 * current thread. This will cause certain asynchronous operations
682 * (such as most <link linkend="gio">gio</link>-based I/O) which are
683 * started in this thread to run under @context and deliver their
684 * results to its main loop, rather than running under the global
685 * default context in the main thread. Note that calling this function
686 * changes the context returned by
687 * g_main_context_get_thread_default(), <emphasis>not</emphasis> the
688 * one returned by g_main_context_default(), so it does not affect the
689 * context used by functions like g_idle_add().
691 * Normally you would call this function shortly after creating a new
692 * thread, passing it a #GMainContext which will be run by a
693 * #GMainLoop in that thread, to set a new default context for all
694 * async operations in that thread. (In this case, you don't need to
695 * ever call g_main_context_pop_thread_default().) In some cases
696 * however, you may want to schedule a single operation in a
697 * non-default context, or temporarily use a non-default context in
698 * the main thread. In that case, you can wrap the call to the
699 * asynchronous operation inside a
700 * g_main_context_push_thread_default() /
701 * g_main_context_pop_thread_default() pair, but it is up to you to
702 * ensure that no other asynchronous operations accidentally get
703 * started while the non-default context is active.
705 * Beware that libraries that predate this function may not correctly
706 * handle being used from a thread with a thread-default context. Eg,
707 * see g_file_supports_thread_contexts().
712 g_main_context_push_thread_default (GMainContext *context)
715 gboolean acquired_context;
717 acquired_context = g_main_context_acquire (context);
718 g_return_if_fail (acquired_context);
720 if (context == g_main_context_default ())
723 g_main_context_ref (context);
725 stack = g_private_get (&thread_context_stack);
728 stack = g_queue_new ();
729 g_private_set (&thread_context_stack, stack);
732 g_queue_push_head (stack, context);
736 * g_main_context_pop_thread_default:
737 * @context: (allow-none): a #GMainContext object, or %NULL
739 * Pops @context off the thread-default context stack (verifying that
740 * it was on the top of the stack).
745 g_main_context_pop_thread_default (GMainContext *context)
749 if (context == g_main_context_default ())
752 stack = g_private_get (&thread_context_stack);
754 g_return_if_fail (stack != NULL);
755 g_return_if_fail (g_queue_peek_head (stack) == context);
757 g_queue_pop_head (stack);
759 g_main_context_release (context);
761 g_main_context_unref (context);
765 * g_main_context_get_thread_default:
767 * Gets the thread-default #GMainContext for this thread. Asynchronous
768 * operations that want to be able to be run in contexts other than
769 * the default one should call this method or
770 * g_main_context_ref_thread_default() to get a #GMainContext to add
771 * their #GSource<!-- -->s to. (Note that even in single-threaded
772 * programs applications may sometimes want to temporarily push a
773 * non-default context, so it is not safe to assume that this will
774 * always return %NULL if you are running in the default thread.)
776 * If you need to hold a reference on the context, use
777 * g_main_context_ref_thread_default() instead.
779 * Returns: (transfer none): the thread-default #GMainContext, or
780 * %NULL if the thread-default context is the global default context.
785 g_main_context_get_thread_default (void)
789 stack = g_private_get (&thread_context_stack);
791 return g_queue_peek_head (stack);
797 * g_main_context_ref_thread_default:
799 * Gets the thread-default #GMainContext for this thread, as with
800 * g_main_context_get_thread_default(), but also adds a reference to
801 * it with g_main_context_ref(). In addition, unlike
802 * g_main_context_get_thread_default(), if the thread-default context
803 * is the global default context, this will return that #GMainContext
804 * (with a ref added to it) rather than returning %NULL.
806 * Returns: (transfer full): the thread-default #GMainContext. Unref
807 * with g_main_context_unref() when you are done with it.
812 g_main_context_ref_thread_default (void)
814 GMainContext *context;
816 context = g_main_context_get_thread_default ();
818 context = g_main_context_default ();
819 return g_main_context_ref (context);
822 /* Hooks for adding to the main loop */
826 * @source_funcs: structure containing functions that implement
827 * the sources behavior.
828 * @struct_size: size of the #GSource structure to create.
830 * Creates a new #GSource structure. The size is specified to
831 * allow creating structures derived from #GSource that contain
832 * additional data. The size passed in must be at least
833 * <literal>sizeof (GSource)</literal>.
835 * The source will not initially be associated with any #GMainContext
836 * and must be added to one with g_source_attach() before it will be
839 * Return value: the newly-created #GSource.
842 g_source_new (GSourceFuncs *source_funcs,
847 g_return_val_if_fail (source_funcs != NULL, NULL);
848 g_return_val_if_fail (struct_size >= sizeof (GSource), NULL);
850 source = (GSource*) g_malloc0 (struct_size);
851 source->priv = g_slice_new0 (GSourcePrivate);
852 source->source_funcs = source_funcs;
853 source->ref_count = 1;
855 source->priority = G_PRIORITY_DEFAULT;
857 source->flags = G_HOOK_FLAG_ACTIVE;
859 source->priv->ready_time = -1;
861 /* NULL/0 initialization for all other fields */
866 /* Holds context's lock */
868 g_source_iter_init (GSourceIter *iter,
869 GMainContext *context,
872 iter->context = context;
873 iter->current_list = NULL;
875 iter->may_modify = may_modify;
878 /* Holds context's lock */
880 g_source_iter_next (GSourceIter *iter, GSource **source)
882 GSource *next_source;
885 next_source = iter->source->next;
891 if (iter->current_list)
892 iter->current_list = iter->current_list->next;
894 iter->current_list = iter->context->source_lists;
896 if (iter->current_list)
898 GSourceList *source_list = iter->current_list->data;
900 next_source = source_list->head;
904 /* Note: unreffing iter->source could potentially cause its
905 * GSourceList to be removed from source_lists (if iter->source is
906 * the only source in its list, and it is destroyed), so we have to
907 * keep it reffed until after we advance iter->current_list, above.
910 if (iter->source && iter->may_modify)
911 SOURCE_UNREF (iter->source, iter->context);
912 iter->source = next_source;
913 if (iter->source && iter->may_modify)
914 iter->source->ref_count++;
916 *source = iter->source;
917 return *source != NULL;
920 /* Holds context's lock. Only necessary to call if you broke out of
921 * the g_source_iter_next() loop early.
924 g_source_iter_clear (GSourceIter *iter)
926 if (iter->source && iter->may_modify)
928 SOURCE_UNREF (iter->source, iter->context);
933 /* Holds context's lock
936 find_source_list_for_priority (GMainContext *context,
941 GSourceList *source_list;
944 for (iter = context->source_lists; iter != NULL; last = iter, iter = iter->next)
946 source_list = iter->data;
948 if (source_list->priority == priority)
951 if (source_list->priority > priority)
956 source_list = g_slice_new0 (GSourceList);
957 source_list->priority = priority;
958 context->source_lists = g_list_insert_before (context->source_lists,
968 source_list = g_slice_new0 (GSourceList);
969 source_list->priority = priority;
972 context->source_lists = g_list_append (NULL, source_list);
975 /* This just appends source_list to the end of
976 * context->source_lists without having to walk the list again.
978 last = g_list_append (last, source_list);
983 /* Holds context's lock
986 source_add_to_context (GSource *source,
987 GMainContext *context)
989 GSourceList *source_list;
990 GSource *prev, *next;
992 source_list = find_source_list_for_priority (context, source->priority, TRUE);
994 if (source->priv->parent_source)
996 g_assert (source_list->head != NULL);
998 /* Put the source immediately before its parent */
999 prev = source->priv->parent_source->prev;
1000 next = source->priv->parent_source;
1004 prev = source_list->tail;
1008 source->next = next;
1010 next->prev = source;
1012 source_list->tail = source;
1014 source->prev = prev;
1016 prev->next = source;
1018 source_list->head = source;
1021 /* Holds context's lock
1024 source_remove_from_context (GSource *source,
1025 GMainContext *context)
1027 GSourceList *source_list;
1029 source_list = find_source_list_for_priority (context, source->priority, FALSE);
1030 g_return_if_fail (source_list != NULL);
1033 source->prev->next = source->next;
1035 source_list->head = source->next;
1038 source->next->prev = source->prev;
1040 source_list->tail = source->prev;
1042 source->prev = NULL;
1043 source->next = NULL;
1045 if (source_list->head == NULL)
1047 context->source_lists = g_list_remove (context->source_lists, source_list);
1048 g_slice_free (GSourceList, source_list);
1051 if (context->overflow_used_source_ids)
1052 g_hash_table_remove (context->overflow_used_source_ids,
1053 GUINT_TO_POINTER (source->source_id));
1058 assign_source_id_unlocked (GMainContext *context,
1063 /* Are we about to overflow back to 0?
1064 * See https://bugzilla.gnome.org/show_bug.cgi?id=687098
1066 if (G_UNLIKELY (context->next_id == G_MAXUINT &&
1067 context->overflow_used_source_ids == NULL))
1072 context->overflow_used_source_ids = g_hash_table_new (NULL, NULL);
1074 g_source_iter_init (&iter, context, FALSE);
1075 while (g_source_iter_next (&iter, &source))
1077 g_hash_table_add (context->overflow_used_source_ids,
1078 GUINT_TO_POINTER (source->source_id));
1081 g_hash_table_add (context->overflow_used_source_ids, GUINT_TO_POINTER (id));
1083 else if (context->overflow_used_source_ids == NULL)
1085 id = context->next_id++;
1090 * If we overran G_MAXUINT, we fall back to randomly probing the
1091 * source ids for the current context. This will be slower the more
1092 * sources there are, but we're mainly concerned right now about
1093 * correctness and code size. There's time for a more clever solution
1097 id = g_random_int ();
1099 g_hash_table_contains (context->overflow_used_source_ids,
1100 GUINT_TO_POINTER (id)));
1101 g_hash_table_add (context->overflow_used_source_ids, GUINT_TO_POINTER (id));
1104 source->source_id = id;
1108 g_source_attach_unlocked (GSource *source,
1109 GMainContext *context,
1114 source->context = context;
1115 assign_source_id_unlocked (context, source);
1116 source->ref_count++;
1117 source_add_to_context (source, context);
1119 if (!SOURCE_BLOCKED (source))
1121 tmp_list = source->poll_fds;
1124 g_main_context_add_poll_unlocked (context, source->priority, tmp_list->data);
1125 tmp_list = tmp_list->next;
1128 for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
1129 g_main_context_add_poll_unlocked (context, source->priority, tmp_list->data);
1132 tmp_list = source->priv->child_sources;
1135 g_source_attach_unlocked (tmp_list->data, context, FALSE);
1136 tmp_list = tmp_list->next;
1139 /* If another thread has acquired the context, wake it up since it
1140 * might be in poll() right now.
1142 if (do_wakeup && context->owner && context->owner != G_THREAD_SELF)
1143 g_wakeup_signal (context->wakeup);
1145 return source->source_id;
1150 * @source: a #GSource
1151 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
1153 * Adds a #GSource to a @context so that it will be executed within
1154 * that context. Remove it by calling g_source_destroy().
1156 * Return value: the ID (greater than 0) for the source within the
1160 g_source_attach (GSource *source,
1161 GMainContext *context)
1165 g_return_val_if_fail (source->context == NULL, 0);
1166 g_return_val_if_fail (!SOURCE_DESTROYED (source), 0);
1169 context = g_main_context_default ();
1171 LOCK_CONTEXT (context);
1173 result = g_source_attach_unlocked (source, context, TRUE);
1175 UNLOCK_CONTEXT (context);
1181 g_source_destroy_internal (GSource *source,
1182 GMainContext *context,
1186 LOCK_CONTEXT (context);
1188 if (!SOURCE_DESTROYED (source))
1191 gpointer old_cb_data;
1192 GSourceCallbackFuncs *old_cb_funcs;
1194 source->flags &= ~G_HOOK_FLAG_ACTIVE;
1196 old_cb_data = source->callback_data;
1197 old_cb_funcs = source->callback_funcs;
1199 source->callback_data = NULL;
1200 source->callback_funcs = NULL;
1204 UNLOCK_CONTEXT (context);
1205 old_cb_funcs->unref (old_cb_data);
1206 LOCK_CONTEXT (context);
1209 if (!SOURCE_BLOCKED (source))
1211 tmp_list = source->poll_fds;
1214 g_main_context_remove_poll_unlocked (context, tmp_list->data);
1215 tmp_list = tmp_list->next;
1218 for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
1219 g_main_context_remove_poll_unlocked (context, tmp_list->data);
1222 while (source->priv->child_sources)
1223 g_child_source_remove_internal (source->priv->child_sources->data, context);
1225 if (source->priv->parent_source)
1226 g_child_source_remove_internal (source, context);
1228 g_source_unref_internal (source, context, TRUE);
1232 UNLOCK_CONTEXT (context);
1237 * @source: a #GSource
1239 * Removes a source from its #GMainContext, if any, and mark it as
1240 * destroyed. The source cannot be subsequently added to another
1244 g_source_destroy (GSource *source)
1246 GMainContext *context;
1248 g_return_if_fail (source != NULL);
1250 context = source->context;
1253 g_source_destroy_internal (source, context, FALSE);
1255 source->flags &= ~G_HOOK_FLAG_ACTIVE;
1260 * @source: a #GSource
1262 * Returns the numeric ID for a particular source. The ID of a source
1263 * is a positive integer which is unique within a particular main loop
1264 * context. The reverse
1265 * mapping from ID to source is done by g_main_context_find_source_by_id().
1267 * Return value: the ID (greater than 0) for the source
1270 g_source_get_id (GSource *source)
1274 g_return_val_if_fail (source != NULL, 0);
1275 g_return_val_if_fail (source->context != NULL, 0);
1277 LOCK_CONTEXT (source->context);
1278 result = source->source_id;
1279 UNLOCK_CONTEXT (source->context);
1285 * g_source_get_context:
1286 * @source: a #GSource
1288 * Gets the #GMainContext with which the source is associated.
1290 * You can call this on a source that has been destroyed, provided
1291 * that the #GMainContext it was attached to still exists (in which
1292 * case it will return that #GMainContext). In particular, you can
1293 * always call this function on the source returned from
1294 * g_main_current_source(). But calling this function on a source
1295 * whose #GMainContext has been destroyed is an error.
1297 * Return value: (transfer none) (allow-none): the #GMainContext with which the
1298 * source is associated, or %NULL if the context has not
1299 * yet been added to a source.
1302 g_source_get_context (GSource *source)
1304 g_return_val_if_fail (source->context != NULL || !SOURCE_DESTROYED (source), NULL);
1306 return source->context;
1310 * g_source_add_poll:
1311 * @source:a #GSource
1312 * @fd: a #GPollFD structure holding information about a file
1313 * descriptor to watch.
1315 * Adds a file descriptor to the set of file descriptors polled for
1316 * this source. This is usually combined with g_source_new() to add an
1317 * event source. The event source's check function will typically test
1318 * the @revents field in the #GPollFD struct and return %TRUE if events need
1321 * Using this API forces the linear scanning of event sources on each
1322 * main loop iteration. Newly-written event sources should try to use
1323 * g_source_add_unix_fd() instead of this API.
1326 g_source_add_poll (GSource *source,
1329 GMainContext *context;
1331 g_return_if_fail (source != NULL);
1332 g_return_if_fail (fd != NULL);
1333 g_return_if_fail (!SOURCE_DESTROYED (source));
1335 context = source->context;
1338 LOCK_CONTEXT (context);
1340 source->poll_fds = g_slist_prepend (source->poll_fds, fd);
1344 if (!SOURCE_BLOCKED (source))
1345 g_main_context_add_poll_unlocked (context, source->priority, fd);
1346 UNLOCK_CONTEXT (context);
1351 * g_source_remove_poll:
1352 * @source:a #GSource
1353 * @fd: a #GPollFD structure previously passed to g_source_add_poll().
1355 * Removes a file descriptor from the set of file descriptors polled for
1359 g_source_remove_poll (GSource *source,
1362 GMainContext *context;
1364 g_return_if_fail (source != NULL);
1365 g_return_if_fail (fd != NULL);
1366 g_return_if_fail (!SOURCE_DESTROYED (source));
1368 context = source->context;
1371 LOCK_CONTEXT (context);
1373 source->poll_fds = g_slist_remove (source->poll_fds, fd);
1377 if (!SOURCE_BLOCKED (source))
1378 g_main_context_remove_poll_unlocked (context, fd);
1379 UNLOCK_CONTEXT (context);
1384 * g_source_add_child_source:
1385 * @source:a #GSource
1386 * @child_source: a second #GSource that @source should "poll"
1388 * Adds @child_source to @source as a "polled" source; when @source is
1389 * added to a #GMainContext, @child_source will be automatically added
1390 * with the same priority, when @child_source is triggered, it will
1391 * cause @source to dispatch (in addition to calling its own
1392 * callback), and when @source is destroyed, it will destroy
1393 * @child_source as well. (@source will also still be dispatched if
1394 * its own prepare/check functions indicate that it is ready.)
1396 * If you don't need @child_source to do anything on its own when it
1397 * triggers, you can call g_source_set_dummy_callback() on it to set a
1398 * callback that does nothing (except return %TRUE if appropriate).
1400 * @source will hold a reference on @child_source while @child_source
1401 * is attached to it.
1406 g_source_add_child_source (GSource *source,
1407 GSource *child_source)
1409 GMainContext *context;
1411 g_return_if_fail (source != NULL);
1412 g_return_if_fail (child_source != NULL);
1413 g_return_if_fail (!SOURCE_DESTROYED (source));
1414 g_return_if_fail (!SOURCE_DESTROYED (child_source));
1415 g_return_if_fail (child_source->context == NULL);
1416 g_return_if_fail (child_source->priv->parent_source == NULL);
1418 context = source->context;
1421 LOCK_CONTEXT (context);
1423 source->priv->child_sources = g_slist_prepend (source->priv->child_sources,
1424 g_source_ref (child_source));
1425 child_source->priv->parent_source = source;
1426 g_source_set_priority_unlocked (child_source, NULL, source->priority);
1427 if (SOURCE_BLOCKED (source))
1428 block_source (child_source);
1432 g_source_attach_unlocked (child_source, context, TRUE);
1433 UNLOCK_CONTEXT (context);
1438 g_child_source_remove_internal (GSource *child_source,
1439 GMainContext *context)
1441 GSource *parent_source = child_source->priv->parent_source;
1443 parent_source->priv->child_sources =
1444 g_slist_remove (parent_source->priv->child_sources, child_source);
1445 child_source->priv->parent_source = NULL;
1447 g_source_destroy_internal (child_source, context, TRUE);
1448 g_source_unref_internal (child_source, context, TRUE);
1452 * g_source_remove_child_source:
1453 * @source:a #GSource
1454 * @child_source: a #GSource previously passed to
1455 * g_source_add_child_source().
1457 * Detaches @child_source from @source and destroys it.
1462 g_source_remove_child_source (GSource *source,
1463 GSource *child_source)
1465 GMainContext *context;
1467 g_return_if_fail (source != NULL);
1468 g_return_if_fail (child_source != NULL);
1469 g_return_if_fail (child_source->priv->parent_source == source);
1470 g_return_if_fail (!SOURCE_DESTROYED (source));
1471 g_return_if_fail (!SOURCE_DESTROYED (child_source));
1473 context = source->context;
1476 LOCK_CONTEXT (context);
1478 g_child_source_remove_internal (child_source, context);
1481 UNLOCK_CONTEXT (context);
1485 * g_source_set_callback_indirect:
1486 * @source: the source
1487 * @callback_data: pointer to callback data "object"
1488 * @callback_funcs: functions for reference counting @callback_data
1489 * and getting the callback and data
1491 * Sets the callback function storing the data as a refcounted callback
1492 * "object". This is used internally. Note that calling
1493 * g_source_set_callback_indirect() assumes
1494 * an initial reference count on @callback_data, and thus
1495 * @callback_funcs->unref will eventually be called once more
1496 * than @callback_funcs->ref.
1499 g_source_set_callback_indirect (GSource *source,
1500 gpointer callback_data,
1501 GSourceCallbackFuncs *callback_funcs)
1503 GMainContext *context;
1504 gpointer old_cb_data;
1505 GSourceCallbackFuncs *old_cb_funcs;
1507 g_return_if_fail (source != NULL);
1508 g_return_if_fail (callback_funcs != NULL || callback_data == NULL);
1510 context = source->context;
1513 LOCK_CONTEXT (context);
1515 old_cb_data = source->callback_data;
1516 old_cb_funcs = source->callback_funcs;
1518 source->callback_data = callback_data;
1519 source->callback_funcs = callback_funcs;
1522 UNLOCK_CONTEXT (context);
1525 old_cb_funcs->unref (old_cb_data);
1529 g_source_callback_ref (gpointer cb_data)
1531 GSourceCallback *callback = cb_data;
1533 callback->ref_count++;
1538 g_source_callback_unref (gpointer cb_data)
1540 GSourceCallback *callback = cb_data;
1542 callback->ref_count--;
1543 if (callback->ref_count == 0)
1545 if (callback->notify)
1546 callback->notify (callback->data);
1552 g_source_callback_get (gpointer cb_data,
1557 GSourceCallback *callback = cb_data;
1559 *func = callback->func;
1560 *data = callback->data;
1563 static GSourceCallbackFuncs g_source_callback_funcs = {
1564 g_source_callback_ref,
1565 g_source_callback_unref,
1566 g_source_callback_get,
1570 * g_source_set_callback:
1571 * @source: the source
1572 * @func: a callback function
1573 * @data: the data to pass to callback function
1574 * @notify: (allow-none): a function to call when @data is no longer in use, or %NULL.
1576 * Sets the callback function for a source. The callback for a source is
1577 * called from the source's dispatch function.
1579 * The exact type of @func depends on the type of source; ie. you
1580 * should not count on @func being called with @data as its first
1583 * Typically, you won't use this function. Instead use functions specific
1584 * to the type of source you are using.
1587 g_source_set_callback (GSource *source,
1590 GDestroyNotify notify)
1592 GSourceCallback *new_callback;
1594 g_return_if_fail (source != NULL);
1596 new_callback = g_new (GSourceCallback, 1);
1598 new_callback->ref_count = 1;
1599 new_callback->func = func;
1600 new_callback->data = data;
1601 new_callback->notify = notify;
1603 g_source_set_callback_indirect (source, new_callback, &g_source_callback_funcs);
1608 * g_source_set_funcs:
1609 * @source: a #GSource
1610 * @funcs: the new #GSourceFuncs
1612 * Sets the source functions (can be used to override
1613 * default implementations) of an unattached source.
1618 g_source_set_funcs (GSource *source,
1619 GSourceFuncs *funcs)
1621 g_return_if_fail (source != NULL);
1622 g_return_if_fail (source->context == NULL);
1623 g_return_if_fail (source->ref_count > 0);
1624 g_return_if_fail (funcs != NULL);
1626 source->source_funcs = funcs;
1630 g_source_set_priority_unlocked (GSource *source,
1631 GMainContext *context,
1636 g_return_if_fail (source->priv->parent_source == NULL ||
1637 source->priv->parent_source->priority == priority);
1641 /* Remove the source from the context's source and then
1642 * add it back after so it is sorted in the correct place
1644 source_remove_from_context (source, source->context);
1647 source->priority = priority;
1651 source_add_to_context (source, source->context);
1653 if (!SOURCE_BLOCKED (source))
1655 tmp_list = source->poll_fds;
1658 g_main_context_remove_poll_unlocked (context, tmp_list->data);
1659 g_main_context_add_poll_unlocked (context, priority, tmp_list->data);
1661 tmp_list = tmp_list->next;
1664 for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
1666 g_main_context_remove_poll_unlocked (context, tmp_list->data);
1667 g_main_context_add_poll_unlocked (context, priority, tmp_list->data);
1672 if (source->priv->child_sources)
1674 tmp_list = source->priv->child_sources;
1677 g_source_set_priority_unlocked (tmp_list->data, context, priority);
1678 tmp_list = tmp_list->next;
1684 * g_source_set_priority:
1685 * @source: a #GSource
1686 * @priority: the new priority.
1688 * Sets the priority of a source. While the main loop is being run, a
1689 * source will be dispatched if it is ready to be dispatched and no
1690 * sources at a higher (numerically smaller) priority are ready to be
1694 g_source_set_priority (GSource *source,
1697 GMainContext *context;
1699 g_return_if_fail (source != NULL);
1701 context = source->context;
1704 LOCK_CONTEXT (context);
1705 g_source_set_priority_unlocked (source, context, priority);
1707 UNLOCK_CONTEXT (source->context);
1711 * g_source_get_priority:
1712 * @source: a #GSource
1714 * Gets the priority of a source.
1716 * Return value: the priority of the source
1719 g_source_get_priority (GSource *source)
1721 g_return_val_if_fail (source != NULL, 0);
1723 return source->priority;
1727 * g_source_set_ready_time:
1728 * @source: a #GSource
1729 * @ready_time: the monotonic time at which the source will be ready,
1730 * 0 for "immediately", -1 for "never"
1732 * Sets a #GSource to be dispatched when the given monotonic time is
1733 * reached (or passed). If the monotonic time is in the past (as it
1734 * always will be if @ready_time is 0) then the source will be
1735 * dispatched immediately.
1737 * If @ready_time is -1 then the source is never woken up on the basis
1738 * of the passage of time.
1740 * Dispatching the source does not reset the ready time. You should do
1741 * so yourself, from the source dispatch function.
1743 * Note that if you have a pair of sources where the ready time of one
1744 * suggests that it will be delivered first but the priority for the
1745 * other suggests that it would be delivered first, and the ready time
1746 * for both sources is reached during the same main context iteration
1747 * then the order of dispatch is undefined.
1752 g_source_set_ready_time (GSource *source,
1755 GMainContext *context;
1757 g_return_if_fail (source != NULL);
1758 g_return_if_fail (source->ref_count > 0);
1760 if (source->priv->ready_time == ready_time)
1763 context = source->context;
1766 LOCK_CONTEXT (context);
1768 source->priv->ready_time = ready_time;
1772 /* Quite likely that we need to change the timeout on the poll */
1773 if (!SOURCE_BLOCKED (source))
1774 g_wakeup_signal (context->wakeup);
1775 UNLOCK_CONTEXT (context);
1780 * g_source_get_ready_time:
1781 * @source: a #GSource
1783 * Gets the "ready time" of @source, as set by
1784 * g_source_set_ready_time().
1786 * Any time before the current monotonic time (including 0) is an
1787 * indication that the source will fire immediately.
1789 * Returns: the monotonic ready time, -1 for "never"
1792 g_source_get_ready_time (GSource *source)
1794 g_return_val_if_fail (source != NULL, -1);
1796 return source->priv->ready_time;
1800 * g_source_set_can_recurse:
1801 * @source: a #GSource
1802 * @can_recurse: whether recursion is allowed for this source
1804 * Sets whether a source can be called recursively. If @can_recurse is
1805 * %TRUE, then while the source is being dispatched then this source
1806 * will be processed normally. Otherwise, all processing of this
1807 * source is blocked until the dispatch function returns.
1810 g_source_set_can_recurse (GSource *source,
1811 gboolean can_recurse)
1813 GMainContext *context;
1815 g_return_if_fail (source != NULL);
1817 context = source->context;
1820 LOCK_CONTEXT (context);
1823 source->flags |= G_SOURCE_CAN_RECURSE;
1825 source->flags &= ~G_SOURCE_CAN_RECURSE;
1828 UNLOCK_CONTEXT (context);
1832 * g_source_get_can_recurse:
1833 * @source: a #GSource
1835 * Checks whether a source is allowed to be called recursively.
1836 * see g_source_set_can_recurse().
1838 * Return value: whether recursion is allowed.
1841 g_source_get_can_recurse (GSource *source)
1843 g_return_val_if_fail (source != NULL, FALSE);
1845 return (source->flags & G_SOURCE_CAN_RECURSE) != 0;
1850 * g_source_set_name:
1851 * @source: a #GSource
1852 * @name: debug name for the source
1854 * Sets a name for the source, used in debugging and profiling.
1855 * The name defaults to #NULL.
1857 * The source name should describe in a human-readable way
1858 * what the source does. For example, "X11 event queue"
1859 * or "GTK+ repaint idle handler" or whatever it is.
1861 * It is permitted to call this function multiple times, but is not
1862 * recommended due to the potential performance impact. For example,
1863 * one could change the name in the "check" function of a #GSourceFuncs
1864 * to include details like the event type in the source name.
1869 g_source_set_name (GSource *source,
1872 g_return_if_fail (source != NULL);
1874 /* setting back to NULL is allowed, just because it's
1875 * weird if get_name can return NULL but you can't
1879 g_free (source->name);
1880 source->name = g_strdup (name);
1884 * g_source_get_name:
1885 * @source: a #GSource
1887 * Gets a name for the source, used in debugging and profiling.
1888 * The name may be #NULL if it has never been set with
1889 * g_source_set_name().
1891 * Return value: the name of the source
1895 g_source_get_name (GSource *source)
1897 g_return_val_if_fail (source != NULL, NULL);
1899 return source->name;
1903 * g_source_set_name_by_id:
1904 * @tag: a #GSource ID
1905 * @name: debug name for the source
1907 * Sets the name of a source using its ID.
1909 * This is a convenience utility to set source names from the return
1910 * value of g_idle_add(), g_timeout_add(), etc.
1915 g_source_set_name_by_id (guint tag,
1920 g_return_if_fail (tag > 0);
1922 source = g_main_context_find_source_by_id (NULL, tag);
1926 g_source_set_name (source, name);
1932 * @source: a #GSource
1934 * Increases the reference count on a source by one.
1936 * Return value: @source
1939 g_source_ref (GSource *source)
1941 GMainContext *context;
1943 g_return_val_if_fail (source != NULL, NULL);
1945 context = source->context;
1948 LOCK_CONTEXT (context);
1950 source->ref_count++;
1953 UNLOCK_CONTEXT (context);
1958 /* g_source_unref() but possible to call within context lock
1961 g_source_unref_internal (GSource *source,
1962 GMainContext *context,
1965 gpointer old_cb_data = NULL;
1966 GSourceCallbackFuncs *old_cb_funcs = NULL;
1968 g_return_if_fail (source != NULL);
1970 if (!have_lock && context)
1971 LOCK_CONTEXT (context);
1973 source->ref_count--;
1974 if (source->ref_count == 0)
1976 old_cb_data = source->callback_data;
1977 old_cb_funcs = source->callback_funcs;
1979 source->callback_data = NULL;
1980 source->callback_funcs = NULL;
1984 if (!SOURCE_DESTROYED (source))
1985 g_warning (G_STRLOC ": ref_count == 0, but source was still attached to a context!");
1986 source_remove_from_context (source, context);
1989 if (source->source_funcs->finalize)
1992 UNLOCK_CONTEXT (context);
1993 source->source_funcs->finalize (source);
1995 LOCK_CONTEXT (context);
1998 g_free (source->name);
1999 source->name = NULL;
2001 g_slist_free (source->poll_fds);
2002 source->poll_fds = NULL;
2004 g_slist_free_full (source->priv->fds, g_free);
2006 g_slice_free (GSourcePrivate, source->priv);
2007 source->priv = NULL;
2012 if (!have_lock && context)
2013 UNLOCK_CONTEXT (context);
2018 UNLOCK_CONTEXT (context);
2020 old_cb_funcs->unref (old_cb_data);
2023 LOCK_CONTEXT (context);
2029 * @source: a #GSource
2031 * Decreases the reference count of a source by one. If the
2032 * resulting reference count is zero the source and associated
2033 * memory will be destroyed.
2036 g_source_unref (GSource *source)
2038 g_return_if_fail (source != NULL);
2040 g_source_unref_internal (source, source->context, FALSE);
2044 * g_main_context_find_source_by_id:
2045 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
2046 * @source_id: the source ID, as returned by g_source_get_id().
2048 * Finds a #GSource given a pair of context and ID.
2050 * Return value: (transfer none): the #GSource if found, otherwise, %NULL
2053 g_main_context_find_source_by_id (GMainContext *context,
2059 g_return_val_if_fail (source_id > 0, NULL);
2061 if (context == NULL)
2062 context = g_main_context_default ();
2064 LOCK_CONTEXT (context);
2066 g_source_iter_init (&iter, context, FALSE);
2067 while (g_source_iter_next (&iter, &source))
2069 if (!SOURCE_DESTROYED (source) &&
2070 source->source_id == source_id)
2073 g_source_iter_clear (&iter);
2075 UNLOCK_CONTEXT (context);
2081 * g_main_context_find_source_by_funcs_user_data:
2082 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used).
2083 * @funcs: the @source_funcs passed to g_source_new().
2084 * @user_data: the user data from the callback.
2086 * Finds a source with the given source functions and user data. If
2087 * multiple sources exist with the same source function and user data,
2088 * the first one found will be returned.
2090 * Return value: (transfer none): the source, if one was found, otherwise %NULL
2093 g_main_context_find_source_by_funcs_user_data (GMainContext *context,
2094 GSourceFuncs *funcs,
2100 g_return_val_if_fail (funcs != NULL, NULL);
2102 if (context == NULL)
2103 context = g_main_context_default ();
2105 LOCK_CONTEXT (context);
2107 g_source_iter_init (&iter, context, FALSE);
2108 while (g_source_iter_next (&iter, &source))
2110 if (!SOURCE_DESTROYED (source) &&
2111 source->source_funcs == funcs &&
2112 source->callback_funcs)
2114 GSourceFunc callback;
2115 gpointer callback_data;
2117 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
2119 if (callback_data == user_data)
2123 g_source_iter_clear (&iter);
2125 UNLOCK_CONTEXT (context);
2131 * g_main_context_find_source_by_user_data:
2132 * @context: a #GMainContext
2133 * @user_data: the user_data for the callback.
2135 * Finds a source with the given user data for the callback. If
2136 * multiple sources exist with the same user data, the first
2137 * one found will be returned.
2139 * Return value: (transfer none): the source, if one was found, otherwise %NULL
2142 g_main_context_find_source_by_user_data (GMainContext *context,
2148 if (context == NULL)
2149 context = g_main_context_default ();
2151 LOCK_CONTEXT (context);
2153 g_source_iter_init (&iter, context, FALSE);
2154 while (g_source_iter_next (&iter, &source))
2156 if (!SOURCE_DESTROYED (source) &&
2157 source->callback_funcs)
2159 GSourceFunc callback;
2160 gpointer callback_data = NULL;
2162 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
2164 if (callback_data == user_data)
2168 g_source_iter_clear (&iter);
2170 UNLOCK_CONTEXT (context);
2177 * @tag: the ID of the source to remove.
2179 * Removes the source with the given id from the default main context.
2181 * The id of a #GSource is given by g_source_get_id(), or will be
2182 * returned by the functions g_source_attach(), g_idle_add(),
2183 * g_idle_add_full(), g_timeout_add(), g_timeout_add_full(),
2184 * g_child_watch_add(), g_child_watch_add_full(), g_io_add_watch(), and
2185 * g_io_add_watch_full().
2187 * See also g_source_destroy(). You must use g_source_destroy() for sources
2188 * added to a non-default main context.
2190 * It is a programmer error to attempt to remove a non-existent source.
2192 * Return value: For historical reasons, this function always returns %TRUE
2195 g_source_remove (guint tag)
2199 g_return_val_if_fail (tag > 0, FALSE);
2201 source = g_main_context_find_source_by_id (NULL, tag);
2203 g_source_destroy (source);
2205 g_critical ("Source ID %u was not found when attempting to remove it", tag);
2207 return source != NULL;
2211 * g_source_remove_by_user_data:
2212 * @user_data: the user_data for the callback.
2214 * Removes a source from the default main loop context given the user
2215 * data for the callback. If multiple sources exist with the same user
2216 * data, only one will be destroyed.
2218 * Return value: %TRUE if a source was found and removed.
2221 g_source_remove_by_user_data (gpointer user_data)
2225 source = g_main_context_find_source_by_user_data (NULL, user_data);
2228 g_source_destroy (source);
2236 * g_source_remove_by_funcs_user_data:
2237 * @funcs: The @source_funcs passed to g_source_new()
2238 * @user_data: the user data for the callback
2240 * Removes a source from the default main loop context given the
2241 * source functions and user data. If multiple sources exist with the
2242 * same source functions and user data, only one will be destroyed.
2244 * Return value: %TRUE if a source was found and removed.
2247 g_source_remove_by_funcs_user_data (GSourceFuncs *funcs,
2252 g_return_val_if_fail (funcs != NULL, FALSE);
2254 source = g_main_context_find_source_by_funcs_user_data (NULL, funcs, user_data);
2257 g_source_destroy (source);
2266 * g_source_add_unix_fd:
2267 * @source: a #GSource
2268 * @fd: the fd to monitor
2269 * @events: an event mask
2271 * Monitors @fd for the IO events in @events.
2273 * The tag returned by this function can be used to remove or modify the
2274 * monitoring of the fd using g_source_remove_unix_fd() or
2275 * g_source_modify_unix_fd().
2277 * It is not necessary to remove the fd before destroying the source; it
2278 * will be cleaned up automatically.
2280 * As the name suggests, this function is not available on Windows.
2282 * Returns: an opaque tag
2287 g_source_add_unix_fd (GSource *source,
2289 GIOCondition events)
2291 GMainContext *context;
2294 g_return_val_if_fail (source != NULL, NULL);
2295 g_return_val_if_fail (!SOURCE_DESTROYED (source), NULL);
2297 poll_fd = g_new (GPollFD, 1);
2299 poll_fd->events = events;
2300 poll_fd->revents = 0;
2302 context = source->context;
2305 LOCK_CONTEXT (context);
2307 source->priv->fds = g_slist_prepend (source->priv->fds, poll_fd);
2311 if (!SOURCE_BLOCKED (source))
2312 g_main_context_add_poll_unlocked (context, source->priority, poll_fd);
2313 UNLOCK_CONTEXT (context);
2320 * g_source_modify_unix_fd:
2321 * @source: a #GSource
2322 * @tag: the tag from g_source_add_unix_fd()
2323 * @new_events: the new event mask to watch
2325 * Updates the event mask to watch for the fd identified by @tag.
2327 * @tag is the tag returned from g_source_add_unix_fd().
2329 * If you want to remove a fd, don't set its event mask to zero.
2330 * Instead, call g_source_remove_unix_fd().
2332 * As the name suggests, this function is not available on Windows.
2337 g_source_modify_unix_fd (GSource *source,
2339 GIOCondition new_events)
2341 GMainContext *context;
2344 g_return_if_fail (source != NULL);
2345 g_return_if_fail (g_slist_find (source->priv->fds, tag));
2347 context = source->context;
2350 poll_fd->events = new_events;
2353 g_main_context_wakeup (context);
2357 * g_source_remove_unix_fd:
2358 * @source: a #GSource
2359 * @tag: the tag from g_source_add_unix_fd()
2361 * Reverses the effect of a previous call to g_source_add_unix_fd().
2363 * You only need to call this if you want to remove an fd from being
2364 * watched while keeping the same source around. In the normal case you
2365 * will just want to destroy the source.
2367 * As the name suggests, this function is not available on Windows.
2372 g_source_remove_unix_fd (GSource *source,
2375 GMainContext *context;
2378 g_return_if_fail (source != NULL);
2379 g_return_if_fail (g_slist_find (source->priv->fds, tag));
2381 context = source->context;
2385 LOCK_CONTEXT (context);
2387 source->priv->fds = g_slist_remove (source->priv->fds, poll_fd);
2391 if (!SOURCE_BLOCKED (source))
2392 g_main_context_remove_poll_unlocked (context, poll_fd);
2394 UNLOCK_CONTEXT (context);
2401 * g_source_query_unix_fd:
2402 * @source: a #GSource
2403 * @tag: the tag from g_source_add_unix_fd()
2405 * Queries the events reported for the fd corresponding to @tag on
2406 * @source during the last poll.
2408 * The return value of this function is only defined when the function
2409 * is called from the check or dispatch functions for @source.
2411 * As the name suggests, this function is not available on Windows.
2413 * Returns: the conditions reported on the fd
2418 g_source_query_unix_fd (GSource *source,
2423 g_return_val_if_fail (source != NULL, 0);
2424 g_return_val_if_fail (g_slist_find (source->priv->fds, tag), 0);
2428 return poll_fd->revents;
2430 #endif /* G_OS_UNIX */
2433 * g_get_current_time:
2434 * @result: #GTimeVal structure in which to store current time.
2436 * Equivalent to the UNIX gettimeofday() function, but portable.
2438 * You may find g_get_real_time() to be more convenient.
2441 g_get_current_time (GTimeVal *result)
2446 g_return_if_fail (result != NULL);
2448 /*this is required on alpha, there the timeval structs are int's
2449 not longs and a cast only would fail horribly*/
2450 gettimeofday (&r, NULL);
2451 result->tv_sec = r.tv_sec;
2452 result->tv_usec = r.tv_usec;
2457 g_return_if_fail (result != NULL);
2459 GetSystemTimeAsFileTime (&ft);
2460 memmove (&time64, &ft, sizeof (FILETIME));
2462 /* Convert from 100s of nanoseconds since 1601-01-01
2463 * to Unix epoch. Yes, this is Y2038 unsafe.
2465 time64 -= G_GINT64_CONSTANT (116444736000000000);
2468 result->tv_sec = time64 / 1000000;
2469 result->tv_usec = time64 % 1000000;
2476 * Queries the system wall-clock time.
2478 * This call is functionally equivalent to g_get_current_time() except
2479 * that the return value is often more convenient than dealing with a
2482 * You should only use this call if you are actually interested in the real
2483 * wall-clock time. g_get_monotonic_time() is probably more useful for
2484 * measuring intervals.
2486 * Returns: the number of microseconds since January 1, 1970 UTC.
2491 g_get_real_time (void)
2495 g_get_current_time (&tv);
2497 return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec;
2501 static ULONGLONG (*g_GetTickCount64) (void) = NULL;
2502 static guint32 g_win32_tick_epoch = 0;
2505 g_clock_win32_init (void)
2509 g_GetTickCount64 = NULL;
2510 kernel32 = GetModuleHandle ("KERNEL32.DLL");
2511 if (kernel32 != NULL)
2512 g_GetTickCount64 = (void *) GetProcAddress (kernel32, "GetTickCount64");
2513 g_win32_tick_epoch = ((guint32)GetTickCount()) >> 31;
2518 * g_get_monotonic_time:
2520 * Queries the system monotonic time, if available.
2522 * On POSIX systems with clock_gettime() and <literal>CLOCK_MONOTONIC</literal> this call
2523 * is a very shallow wrapper for that. Otherwise, we make a best effort
2524 * that probably involves returning the wall clock time (with at least
2525 * microsecond accuracy, subject to the limitations of the OS kernel).
2527 * It's important to note that POSIX <literal>CLOCK_MONOTONIC</literal> does
2528 * not count time spent while the machine is suspended.
2530 * On Windows, "limitations of the OS kernel" is a rather substantial
2531 * statement. Depending on the configuration of the system, the wall
2532 * clock time is updated as infrequently as 64 times a second (which
2533 * is approximately every 16ms). Also, on XP (but not on Vista or later)
2534 * the monotonic clock is locally monotonic, but may differ in exact
2535 * value between processes due to timer wrap handling.
2537 * Returns: the monotonic time, in microseconds
2542 g_get_monotonic_time (void)
2544 #ifdef HAVE_CLOCK_GETTIME
2545 /* librt clock_gettime() is our first choice */
2548 #ifdef CLOCK_MONOTONIC
2549 clock_gettime (CLOCK_MONOTONIC, &ts);
2551 clock_gettime (CLOCK_REALTIME, &ts);
2554 /* In theory monotonic time can have any epoch.
2556 * glib presently assumes the following:
2558 * 1) The epoch comes some time after the birth of Jesus of Nazareth, but
2559 * not more than 10000 years later.
2561 * 2) The current time also falls sometime within this range.
2563 * These two reasonable assumptions leave us with a maximum deviation from
2564 * the epoch of 10000 years, or 315569520000000000 seconds.
2566 * If we restrict ourselves to this range then the number of microseconds
2567 * will always fit well inside the constraints of a int64 (by a factor of
2570 * If you actually hit the following assertion, probably you should file a
2571 * bug against your operating system for being excessively silly.
2573 g_assert (G_GINT64_CONSTANT (-315569520000000000) < ts.tv_sec &&
2574 ts.tv_sec < G_GINT64_CONSTANT (315569520000000000));
2576 return (((gint64) ts.tv_sec) * 1000000) + (ts.tv_nsec / 1000);
2578 #elif defined (G_OS_WIN32)
2582 /* There are four sources for the monotonic time on Windows:
2584 * Three are based on a (1 msec accuracy, but only read periodically) clock chip:
2585 * - GetTickCount (GTC)
2586 * 32bit msec counter, updated each ~15msec, wraps in ~50 days
2587 * - GetTickCount64 (GTC64)
2588 * Same as GetTickCount, but extended to 64bit, so no wrap
2589 * Only available in Vista or later
2590 * - timeGetTime (TGT)
2591 * similar to GetTickCount by default: 15msec, 50 day wrap.
2592 * available in winmm.dll (thus known as the multimedia timers)
2593 * However apps can raise the system timer clock frequency using timeBeginPeriod()
2594 * increasing the accuracy up to 1 msec, at a cost in general system performance
2597 * One is based on high precision clocks:
2598 * - QueryPrecisionCounter (QPC)
2599 * This has much higher accuracy, but is not guaranteed monotonic, and
2600 * has lots of complications like clock jumps and different times on different
2601 * CPUs. It also has lower long term accuracy (i.e. it will drift compared to
2602 * the low precision clocks.
2604 * Additionally, the precision available in the timer-based wakeup such as
2605 * MsgWaitForMultipleObjectsEx (which is what the mainloop is based on) is based
2606 * on the TGT resolution, so by default it is ~15msec, but can be increased by apps.
2608 * The QPC timer has too many issues to be used as is. The only way it could be used
2609 * is to use it to interpolate the lower precision clocks. Firefox does something like
2611 * https://bugzilla.mozilla.org/show_bug.cgi?id=363258
2613 * However this seems quite complicated, so we're not doing this right now.
2615 * The approach we take instead is to use the TGT timer, extending it to 64bit
2616 * either by using the GTC64 value, or if that is not available, a process local
2617 * time epoch that we increment when we detect a timer wrap (assumes that we read
2618 * the time at least once every 50 days).
2621 * - We have a globally consistent monotonic clock on Vista and later
2622 * - We have a locally monotonic clock on XP
2623 * - Apps that need higher precision in timeouts and clock reads can call
2624 * timeBeginPeriod() to increase it as much as they want
2627 if (g_GetTickCount64 != NULL)
2629 guint32 ticks_as_32bit;
2631 ticks = g_GetTickCount64 ();
2632 ticks32 = timeGetTime();
2634 /* GTC64 and TGT are sampled at different times, however they
2635 * have the same base and source (msecs since system boot).
2636 * They can differ by as much as -16 to +16 msecs.
2637 * We can't just inject the low bits into the 64bit counter
2638 * as one of the counters can have wrapped in 32bit space and
2639 * the other not. Instead we calculate the signed difference
2640 * in 32bit space and apply that difference to the 64bit counter.
2642 ticks_as_32bit = (guint32)ticks;
2644 /* We could do some 2's complement hack, but we play it safe */
2645 if (ticks32 - ticks_as_32bit <= G_MAXINT32)
2646 ticks += ticks32 - ticks_as_32bit;
2648 ticks -= ticks_as_32bit - ticks32;
2654 epoch = g_atomic_int_get (&g_win32_tick_epoch);
2656 /* Must read ticks after the epoch. Then we're guaranteed
2657 * that the ticks value we read is higher or equal to any
2658 * previous ones that lead to the writing of the epoch.
2660 ticks32 = timeGetTime();
2662 /* We store the MSB of the current time as the LSB
2663 * of the epoch. Comparing these bits lets us detect when
2664 * the 32bit counter has wrapped so we can increase the
2667 * This will work as long as this function is called at
2668 * least once every ~24 days, which is half the wrap time
2669 * of a 32bit msec counter. I think this is pretty likely.
2671 * Note that g_win32_tick_epoch is a process local state,
2672 * so the monotonic clock will not be the same between
2675 if ((ticks32 >> 31) != (epoch & 1))
2678 g_atomic_int_set (&g_win32_tick_epoch, epoch);
2682 ticks = (guint64)ticks32 | ((guint64)epoch) << 31;
2685 return ticks * 1000;
2687 #else /* !HAVE_CLOCK_GETTIME && ! G_OS_WIN32*/
2691 g_get_current_time (&tv);
2693 return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec;
2698 g_main_dispatch_free (gpointer dispatch)
2700 g_slice_free (GMainDispatch, dispatch);
2703 /* Running the main loop */
2705 static GMainDispatch *
2708 static GPrivate depth_private = G_PRIVATE_INIT (g_main_dispatch_free);
2709 GMainDispatch *dispatch;
2711 dispatch = g_private_get (&depth_private);
2715 dispatch = g_slice_new0 (GMainDispatch);
2716 g_private_set (&depth_private, dispatch);
2725 * Returns the depth of the stack of calls to
2726 * g_main_context_dispatch() on any #GMainContext in the current thread.
2727 * That is, when called from the toplevel, it gives 0. When
2728 * called from within a callback from g_main_context_iteration()
2729 * (or g_main_loop_run(), etc.) it returns 1. When called from within
2730 * a callback to a recursive call to g_main_context_iteration(),
2731 * it returns 2. And so forth.
2733 * This function is useful in a situation like the following:
2734 * Imagine an extremely simple "garbage collected" system.
2737 * static GList *free_list;
2740 * allocate_memory (gsize size)
2742 * gpointer result = g_malloc (size);
2743 * free_list = g_list_prepend (free_list, result);
2748 * free_allocated_memory (void)
2751 * for (l = free_list; l; l = l->next);
2753 * g_list_free (free_list);
2761 * g_main_context_iteration (NULL, TRUE);
2762 * free_allocated_memory();
2766 * This works from an application, however, if you want to do the same
2767 * thing from a library, it gets more difficult, since you no longer
2768 * control the main loop. You might think you can simply use an idle
2769 * function to make the call to free_allocated_memory(), but that
2770 * doesn't work, since the idle function could be called from a
2771 * recursive callback. This can be fixed by using g_main_depth()
2775 * allocate_memory (gsize size)
2777 * FreeListBlock *block = g_new (FreeListBlock, 1);
2778 * block->mem = g_malloc (size);
2779 * block->depth = g_main_depth ();
2780 * free_list = g_list_prepend (free_list, block);
2781 * return block->mem;
2785 * free_allocated_memory (void)
2789 * int depth = g_main_depth ();
2790 * for (l = free_list; l; );
2792 * GList *next = l->next;
2793 * FreeListBlock *block = l->data;
2794 * if (block->depth > depth)
2796 * g_free (block->mem);
2798 * free_list = g_list_delete_link (free_list, l);
2806 * There is a temptation to use g_main_depth() to solve
2807 * problems with reentrancy. For instance, while waiting for data
2808 * to be received from the network in response to a menu item,
2809 * the menu item might be selected again. It might seem that
2810 * one could make the menu item's callback return immediately
2811 * and do nothing if g_main_depth() returns a value greater than 1.
2812 * However, this should be avoided since the user then sees selecting
2813 * the menu item do nothing. Furthermore, you'll find yourself adding
2814 * these checks all over your code, since there are doubtless many,
2815 * many things that the user could do. Instead, you can use the
2816 * following techniques:
2821 * Use gtk_widget_set_sensitive() or modal dialogs to prevent
2822 * the user from interacting with elements while the main
2823 * loop is recursing.
2828 * Avoid main loop recursion in situations where you can't handle
2829 * arbitrary callbacks. Instead, structure your code so that you
2830 * simply return to the main loop and then get called again when
2831 * there is more work to do.
2836 * Return value: The main loop recursion level in the current thread
2841 GMainDispatch *dispatch = get_dispatch ();
2842 return dispatch->depth;
2846 * g_main_current_source:
2848 * Returns the currently firing source for this thread.
2850 * Return value: (transfer none): The currently firing source or %NULL.
2855 g_main_current_source (void)
2857 GMainDispatch *dispatch = get_dispatch ();
2858 return dispatch->source;
2862 * g_source_is_destroyed:
2863 * @source: a #GSource
2865 * Returns whether @source has been destroyed.
2867 * This is important when you operate upon your objects
2868 * from within idle handlers, but may have freed the object
2869 * before the dispatch of your idle handler.
2873 * idle_callback (gpointer data)
2875 * SomeWidget *self = data;
2877 * GDK_THREADS_ENTER (<!-- -->);
2878 * /<!-- -->* do stuff with self *<!-- -->/
2879 * self->idle_id = 0;
2880 * GDK_THREADS_LEAVE (<!-- -->);
2882 * return G_SOURCE_REMOVE;
2886 * some_widget_do_stuff_later (SomeWidget *self)
2888 * self->idle_id = g_idle_add (idle_callback, self);
2892 * some_widget_finalize (GObject *object)
2894 * SomeWidget *self = SOME_WIDGET (object);
2896 * if (self->idle_id)
2897 * g_source_remove (self->idle_id);
2899 * G_OBJECT_CLASS (parent_class)->finalize (object);
2903 * This will fail in a multi-threaded application if the
2904 * widget is destroyed before the idle handler fires due
2905 * to the use after free in the callback. A solution, to
2906 * this particular problem, is to check to if the source
2907 * has already been destroy within the callback.
2911 * idle_callback (gpointer data)
2913 * SomeWidget *self = data;
2915 * GDK_THREADS_ENTER ();
2916 * if (!g_source_is_destroyed (g_main_current_source ()))
2918 * /<!-- -->* do stuff with self *<!-- -->/
2920 * GDK_THREADS_LEAVE ();
2926 * Return value: %TRUE if the source has been destroyed
2931 g_source_is_destroyed (GSource *source)
2933 return SOURCE_DESTROYED (source);
2936 /* Temporarily remove all this source's file descriptors from the
2937 * poll(), so that if data comes available for one of the file descriptors
2938 * we don't continually spin in the poll()
2940 /* HOLDS: source->context's lock */
2942 block_source (GSource *source)
2946 g_return_if_fail (!SOURCE_BLOCKED (source));
2948 source->flags |= G_SOURCE_BLOCKED;
2950 if (source->context)
2952 tmp_list = source->poll_fds;
2955 g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
2956 tmp_list = tmp_list->next;
2959 for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
2960 g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
2963 if (source->priv && source->priv->child_sources)
2965 tmp_list = source->priv->child_sources;
2968 block_source (tmp_list->data);
2969 tmp_list = tmp_list->next;
2974 /* HOLDS: source->context's lock */
2976 unblock_source (GSource *source)
2980 g_return_if_fail (SOURCE_BLOCKED (source)); /* Source already unblocked */
2981 g_return_if_fail (!SOURCE_DESTROYED (source));
2983 source->flags &= ~G_SOURCE_BLOCKED;
2985 tmp_list = source->poll_fds;
2988 g_main_context_add_poll_unlocked (source->context, source->priority, tmp_list->data);
2989 tmp_list = tmp_list->next;
2992 for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
2993 g_main_context_add_poll_unlocked (source->context, source->priority, tmp_list->data);
2995 if (source->priv && source->priv->child_sources)
2997 tmp_list = source->priv->child_sources;
3000 unblock_source (tmp_list->data);
3001 tmp_list = tmp_list->next;
3006 /* HOLDS: context's lock */
3008 g_main_dispatch (GMainContext *context)
3010 GMainDispatch *current = get_dispatch ();
3013 for (i = 0; i < context->pending_dispatches->len; i++)
3015 GSource *source = context->pending_dispatches->pdata[i];
3017 context->pending_dispatches->pdata[i] = NULL;
3020 source->flags &= ~G_SOURCE_READY;
3022 if (!SOURCE_DESTROYED (source))
3024 gboolean was_in_call;
3025 gpointer user_data = NULL;
3026 GSourceFunc callback = NULL;
3027 GSourceCallbackFuncs *cb_funcs;
3029 gboolean need_destroy;
3031 gboolean (*dispatch) (GSource *,
3034 GSource *prev_source;
3036 dispatch = source->source_funcs->dispatch;
3037 cb_funcs = source->callback_funcs;
3038 cb_data = source->callback_data;
3041 cb_funcs->ref (cb_data);
3043 if ((source->flags & G_SOURCE_CAN_RECURSE) == 0)
3044 block_source (source);
3046 was_in_call = source->flags & G_HOOK_FLAG_IN_CALL;
3047 source->flags |= G_HOOK_FLAG_IN_CALL;
3050 cb_funcs->get (cb_data, source, &callback, &user_data);
3052 UNLOCK_CONTEXT (context);
3054 /* These operations are safe because 'current' is thread-local
3055 * and not modified from anywhere but this function.
3057 prev_source = current->source;
3058 current->source = source;
3061 need_destroy = !(* dispatch) (source, callback, user_data);
3063 current->source = prev_source;
3067 cb_funcs->unref (cb_data);
3069 LOCK_CONTEXT (context);
3072 source->flags &= ~G_HOOK_FLAG_IN_CALL;
3074 if (SOURCE_BLOCKED (source) && !SOURCE_DESTROYED (source))
3075 unblock_source (source);
3077 /* Note: this depends on the fact that we can't switch
3078 * sources from one main context to another
3080 if (need_destroy && !SOURCE_DESTROYED (source))
3082 g_assert (source->context == context);
3083 g_source_destroy_internal (source, context, TRUE);
3087 SOURCE_UNREF (source, context);
3090 g_ptr_array_set_size (context->pending_dispatches, 0);
3094 * g_main_context_acquire:
3095 * @context: a #GMainContext
3097 * Tries to become the owner of the specified context.
3098 * If some other thread is the owner of the context,
3099 * returns %FALSE immediately. Ownership is properly
3100 * recursive: the owner can require ownership again
3101 * and will release ownership when g_main_context_release()
3102 * is called as many times as g_main_context_acquire().
3104 * You must be the owner of a context before you
3105 * can call g_main_context_prepare(), g_main_context_query(),
3106 * g_main_context_check(), g_main_context_dispatch().
3108 * Return value: %TRUE if the operation succeeded, and
3109 * this thread is now the owner of @context.
3112 g_main_context_acquire (GMainContext *context)
3114 gboolean result = FALSE;
3115 GThread *self = G_THREAD_SELF;
3117 if (context == NULL)
3118 context = g_main_context_default ();
3120 LOCK_CONTEXT (context);
3122 if (!context->owner)
3124 context->owner = self;
3125 g_assert (context->owner_count == 0);
3128 if (context->owner == self)
3130 context->owner_count++;
3134 UNLOCK_CONTEXT (context);
3140 * g_main_context_release:
3141 * @context: a #GMainContext
3143 * Releases ownership of a context previously acquired by this thread
3144 * with g_main_context_acquire(). If the context was acquired multiple
3145 * times, the ownership will be released only when g_main_context_release()
3146 * is called as many times as it was acquired.
3149 g_main_context_release (GMainContext *context)
3151 if (context == NULL)
3152 context = g_main_context_default ();
3154 LOCK_CONTEXT (context);
3156 context->owner_count--;
3157 if (context->owner_count == 0)
3159 context->owner = NULL;
3161 if (context->waiters)
3163 GMainWaiter *waiter = context->waiters->data;
3164 gboolean loop_internal_waiter = (waiter->mutex == &context->mutex);
3165 context->waiters = g_slist_delete_link (context->waiters,
3167 if (!loop_internal_waiter)
3168 g_mutex_lock (waiter->mutex);
3170 g_cond_signal (waiter->cond);
3172 if (!loop_internal_waiter)
3173 g_mutex_unlock (waiter->mutex);
3177 UNLOCK_CONTEXT (context);
3181 * g_main_context_wait:
3182 * @context: a #GMainContext
3183 * @cond: a condition variable
3184 * @mutex: a mutex, currently held
3186 * Tries to become the owner of the specified context,
3187 * as with g_main_context_acquire(). But if another thread
3188 * is the owner, atomically drop @mutex and wait on @cond until
3189 * that owner releases ownership or until @cond is signaled, then
3190 * try again (once) to become the owner.
3192 * Return value: %TRUE if the operation succeeded, and
3193 * this thread is now the owner of @context.
3196 g_main_context_wait (GMainContext *context,
3200 gboolean result = FALSE;
3201 GThread *self = G_THREAD_SELF;
3202 gboolean loop_internal_waiter;
3204 if (context == NULL)
3205 context = g_main_context_default ();
3207 loop_internal_waiter = (mutex == &context->mutex);
3209 if (!loop_internal_waiter)
3210 LOCK_CONTEXT (context);
3212 if (context->owner && context->owner != self)
3217 waiter.mutex = mutex;
3219 context->waiters = g_slist_append (context->waiters, &waiter);
3221 if (!loop_internal_waiter)
3222 UNLOCK_CONTEXT (context);
3223 g_cond_wait (cond, mutex);
3224 if (!loop_internal_waiter)
3225 LOCK_CONTEXT (context);
3227 context->waiters = g_slist_remove (context->waiters, &waiter);
3230 if (!context->owner)
3232 context->owner = self;
3233 g_assert (context->owner_count == 0);
3236 if (context->owner == self)
3238 context->owner_count++;
3242 if (!loop_internal_waiter)
3243 UNLOCK_CONTEXT (context);
3249 * g_main_context_prepare:
3250 * @context: a #GMainContext
3251 * @priority: location to store priority of highest priority
3252 * source already ready.
3254 * Prepares to poll sources within a main loop. The resulting information
3255 * for polling is determined by calling g_main_context_query ().
3257 * Return value: %TRUE if some source is ready to be dispatched
3261 g_main_context_prepare (GMainContext *context,
3266 gint current_priority = G_MAXINT;
3270 if (context == NULL)
3271 context = g_main_context_default ();
3273 LOCK_CONTEXT (context);
3275 context->time_is_fresh = FALSE;
3277 if (context->in_check_or_prepare)
3279 g_warning ("g_main_context_prepare() called recursively from within a source's check() or "
3280 "prepare() member.");
3281 UNLOCK_CONTEXT (context);
3286 /* If recursing, finish up current dispatch, before starting over */
3287 if (context->pending_dispatches)
3290 g_main_dispatch (context, ¤t_time);
3292 UNLOCK_CONTEXT (context);
3297 /* If recursing, clear list of pending dispatches */
3299 for (i = 0; i < context->pending_dispatches->len; i++)
3301 if (context->pending_dispatches->pdata[i])
3302 SOURCE_UNREF ((GSource *)context->pending_dispatches->pdata[i], context);
3304 g_ptr_array_set_size (context->pending_dispatches, 0);
3306 /* Prepare all sources */
3308 context->timeout = -1;
3310 g_source_iter_init (&iter, context, TRUE);
3311 while (g_source_iter_next (&iter, &source))
3313 gint source_timeout = -1;
3315 if (SOURCE_DESTROYED (source) || SOURCE_BLOCKED (source))
3317 if ((n_ready > 0) && (source->priority > current_priority))
3320 if (!(source->flags & G_SOURCE_READY))
3323 gboolean (* prepare) (GSource *source,
3326 prepare = source->source_funcs->prepare;
3330 context->in_check_or_prepare++;
3331 UNLOCK_CONTEXT (context);
3333 result = (* prepare) (source, &source_timeout);
3335 LOCK_CONTEXT (context);
3336 context->in_check_or_prepare--;
3340 source_timeout = -1;
3344 if (result == FALSE && source->priv->ready_time != -1)
3346 if (!context->time_is_fresh)
3348 context->time = g_get_monotonic_time ();
3349 context->time_is_fresh = TRUE;
3352 if (source->priv->ready_time <= context->time)
3361 /* rounding down will lead to spinning, so always round up */
3362 timeout = (source->priv->ready_time - context->time + 999) / 1000;
3364 if (source_timeout < 0 || timeout < source_timeout)
3365 source_timeout = timeout;
3371 GSource *ready_source = source;
3373 while (ready_source)
3375 ready_source->flags |= G_SOURCE_READY;
3376 ready_source = ready_source->priv->parent_source;
3381 if (source->flags & G_SOURCE_READY)
3384 current_priority = source->priority;
3385 context->timeout = 0;
3388 if (source_timeout >= 0)
3390 if (context->timeout < 0)
3391 context->timeout = source_timeout;
3393 context->timeout = MIN (context->timeout, source_timeout);
3396 g_source_iter_clear (&iter);
3398 UNLOCK_CONTEXT (context);
3401 *priority = current_priority;
3403 return (n_ready > 0);
3407 * g_main_context_query:
3408 * @context: a #GMainContext
3409 * @max_priority: maximum priority source to check
3410 * @timeout_: (out): location to store timeout to be used in polling
3411 * @fds: (out caller-allocates) (array length=n_fds): location to
3412 * store #GPollFD records that need to be polled.
3413 * @n_fds: length of @fds.
3415 * Determines information necessary to poll this main loop.
3417 * Return value: the number of records actually stored in @fds,
3418 * or, if more than @n_fds records need to be stored, the number
3419 * of records that need to be stored.
3422 g_main_context_query (GMainContext *context,
3431 LOCK_CONTEXT (context);
3433 pollrec = context->poll_records;
3435 while (pollrec && max_priority >= pollrec->priority)
3437 /* We need to include entries with fd->events == 0 in the array because
3438 * otherwise if the application changes fd->events behind our back and
3439 * makes it non-zero, we'll be out of sync when we check the fds[] array.
3440 * (Changing fd->events after adding an FD wasn't an anticipated use of
3441 * this API, but it occurs in practice.) */
3444 fds[n_poll].fd = pollrec->fd->fd;
3445 /* In direct contradiction to the Unix98 spec, IRIX runs into
3446 * difficulty if you pass in POLLERR, POLLHUP or POLLNVAL
3447 * flags in the events field of the pollfd while it should
3448 * just ignoring them. So we mask them out here.
3450 fds[n_poll].events = pollrec->fd->events & ~(G_IO_ERR|G_IO_HUP|G_IO_NVAL);
3451 fds[n_poll].revents = 0;
3454 pollrec = pollrec->next;
3458 context->poll_changed = FALSE;
3462 *timeout = context->timeout;
3464 context->time_is_fresh = FALSE;
3467 UNLOCK_CONTEXT (context);
3473 * g_main_context_check:
3474 * @context: a #GMainContext
3475 * @max_priority: the maximum numerical priority of sources to check
3476 * @fds: (array length=n_fds): array of #GPollFD's that was passed to
3477 * the last call to g_main_context_query()
3478 * @n_fds: return value of g_main_context_query()
3480 * Passes the results of polling back to the main loop.
3482 * Return value: %TRUE if some sources are ready to be dispatched.
3485 g_main_context_check (GMainContext *context,
3496 LOCK_CONTEXT (context);
3498 if (context->in_check_or_prepare)
3500 g_warning ("g_main_context_check() called recursively from within a source's check() or "
3501 "prepare() member.");
3502 UNLOCK_CONTEXT (context);
3506 if (context->wake_up_rec.revents)
3507 g_wakeup_acknowledge (context->wakeup);
3509 /* If the set of poll file descriptors changed, bail out
3510 * and let the main loop rerun
3512 if (context->poll_changed)
3514 UNLOCK_CONTEXT (context);
3518 pollrec = context->poll_records;
3522 if (pollrec->fd->events)
3523 pollrec->fd->revents = fds[i].revents;
3525 pollrec = pollrec->next;
3529 g_source_iter_init (&iter, context, TRUE);
3530 while (g_source_iter_next (&iter, &source))
3532 if (SOURCE_DESTROYED (source) || SOURCE_BLOCKED (source))
3534 if ((n_ready > 0) && (source->priority > max_priority))
3537 if (!(source->flags & G_SOURCE_READY))
3540 gboolean (* check) (GSource *source);
3542 check = source->source_funcs->check;
3546 /* If the check function is set, call it. */
3547 context->in_check_or_prepare++;
3548 UNLOCK_CONTEXT (context);
3550 result = (* check) (source);
3552 LOCK_CONTEXT (context);
3553 context->in_check_or_prepare--;
3558 if (result == FALSE)
3562 /* If not already explicitly flagged ready by ->check()
3563 * (or if we have no check) then we can still be ready if
3564 * any of our fds poll as ready.
3566 for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
3568 GPollFD *pollfd = tmp_list->data;
3570 if (pollfd->revents)
3578 if (result == FALSE && source->priv->ready_time != -1)
3580 if (!context->time_is_fresh)
3582 context->time = g_get_monotonic_time ();
3583 context->time_is_fresh = TRUE;
3586 if (source->priv->ready_time <= context->time)
3592 GSource *ready_source = source;
3594 while (ready_source)
3596 ready_source->flags |= G_SOURCE_READY;
3597 ready_source = ready_source->priv->parent_source;
3602 if (source->flags & G_SOURCE_READY)
3604 source->ref_count++;
3605 g_ptr_array_add (context->pending_dispatches, source);
3609 /* never dispatch sources with less priority than the first
3610 * one we choose to dispatch
3612 max_priority = source->priority;
3615 g_source_iter_clear (&iter);
3617 UNLOCK_CONTEXT (context);
3623 * g_main_context_dispatch:
3624 * @context: a #GMainContext
3626 * Dispatches all pending sources.
3629 g_main_context_dispatch (GMainContext *context)
3631 LOCK_CONTEXT (context);
3633 if (context->pending_dispatches->len > 0)
3635 g_main_dispatch (context);
3638 UNLOCK_CONTEXT (context);
3641 /* HOLDS context lock */
3643 g_main_context_iterate (GMainContext *context,
3650 gboolean some_ready;
3651 gint nfds, allocated_nfds;
3652 GPollFD *fds = NULL;
3654 UNLOCK_CONTEXT (context);
3656 if (!g_main_context_acquire (context))
3658 gboolean got_ownership;
3660 LOCK_CONTEXT (context);
3665 got_ownership = g_main_context_wait (context,
3673 LOCK_CONTEXT (context);
3675 if (!context->cached_poll_array)
3677 context->cached_poll_array_size = context->n_poll_records;
3678 context->cached_poll_array = g_new (GPollFD, context->n_poll_records);
3681 allocated_nfds = context->cached_poll_array_size;
3682 fds = context->cached_poll_array;
3684 UNLOCK_CONTEXT (context);
3686 g_main_context_prepare (context, &max_priority);
3688 while ((nfds = g_main_context_query (context, max_priority, &timeout, fds,
3689 allocated_nfds)) > allocated_nfds)
3691 LOCK_CONTEXT (context);
3693 context->cached_poll_array_size = allocated_nfds = nfds;
3694 context->cached_poll_array = fds = g_new (GPollFD, nfds);
3695 UNLOCK_CONTEXT (context);
3701 g_main_context_poll (context, timeout, max_priority, fds, nfds);
3703 some_ready = g_main_context_check (context, max_priority, fds, nfds);
3706 g_main_context_dispatch (context);
3708 g_main_context_release (context);
3710 LOCK_CONTEXT (context);
3716 * g_main_context_pending:
3717 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
3719 * Checks if any sources have pending events for the given context.
3721 * Return value: %TRUE if events are pending.
3724 g_main_context_pending (GMainContext *context)
3729 context = g_main_context_default();
3731 LOCK_CONTEXT (context);
3732 retval = g_main_context_iterate (context, FALSE, FALSE, G_THREAD_SELF);
3733 UNLOCK_CONTEXT (context);
3739 * g_main_context_iteration:
3740 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
3741 * @may_block: whether the call may block.
3743 * Runs a single iteration for the given main loop. This involves
3744 * checking to see if any event sources are ready to be processed,
3745 * then if no events sources are ready and @may_block is %TRUE, waiting
3746 * for a source to become ready, then dispatching the highest priority
3747 * events sources that are ready. Otherwise, if @may_block is %FALSE
3748 * sources are not waited to become ready, only those highest priority
3749 * events sources will be dispatched (if any), that are ready at this
3750 * given moment without further waiting.
3752 * Note that even when @may_block is %TRUE, it is still possible for
3753 * g_main_context_iteration() to return %FALSE, since the wait may
3754 * be interrupted for other reasons than an event source becoming ready.
3756 * Return value: %TRUE if events were dispatched.
3759 g_main_context_iteration (GMainContext *context, gboolean may_block)
3764 context = g_main_context_default();
3766 LOCK_CONTEXT (context);
3767 retval = g_main_context_iterate (context, may_block, TRUE, G_THREAD_SELF);
3768 UNLOCK_CONTEXT (context);
3775 * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used).
3776 * @is_running: set to %TRUE to indicate that the loop is running. This
3777 * is not very important since calling g_main_loop_run() will set this to
3780 * Creates a new #GMainLoop structure.
3782 * Return value: a new #GMainLoop.
3785 g_main_loop_new (GMainContext *context,
3786 gboolean is_running)
3791 context = g_main_context_default();
3793 g_main_context_ref (context);
3795 loop = g_new0 (GMainLoop, 1);
3796 loop->context = context;
3797 loop->is_running = is_running != FALSE;
3798 loop->ref_count = 1;
3805 * @loop: a #GMainLoop
3807 * Increases the reference count on a #GMainLoop object by one.
3809 * Return value: @loop
3812 g_main_loop_ref (GMainLoop *loop)
3814 g_return_val_if_fail (loop != NULL, NULL);
3815 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
3817 g_atomic_int_inc (&loop->ref_count);
3823 * g_main_loop_unref:
3824 * @loop: a #GMainLoop
3826 * Decreases the reference count on a #GMainLoop object by one. If
3827 * the result is zero, free the loop and free all associated memory.
3830 g_main_loop_unref (GMainLoop *loop)
3832 g_return_if_fail (loop != NULL);
3833 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3835 if (!g_atomic_int_dec_and_test (&loop->ref_count))
3838 g_main_context_unref (loop->context);
3844 * @loop: a #GMainLoop
3846 * Runs a main loop until g_main_loop_quit() is called on the loop.
3847 * If this is called for the thread of the loop's #GMainContext,
3848 * it will process events from the loop, otherwise it will
3852 g_main_loop_run (GMainLoop *loop)
3854 GThread *self = G_THREAD_SELF;
3856 g_return_if_fail (loop != NULL);
3857 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3859 if (!g_main_context_acquire (loop->context))
3861 gboolean got_ownership = FALSE;
3863 /* Another thread owns this context */
3864 LOCK_CONTEXT (loop->context);
3866 g_atomic_int_inc (&loop->ref_count);
3868 if (!loop->is_running)
3869 loop->is_running = TRUE;
3871 while (loop->is_running && !got_ownership)
3872 got_ownership = g_main_context_wait (loop->context,
3873 &loop->context->cond,
3874 &loop->context->mutex);
3876 if (!loop->is_running)
3878 UNLOCK_CONTEXT (loop->context);
3880 g_main_context_release (loop->context);
3881 g_main_loop_unref (loop);
3885 g_assert (got_ownership);
3888 LOCK_CONTEXT (loop->context);
3890 if (loop->context->in_check_or_prepare)
3892 g_warning ("g_main_loop_run(): called recursively from within a source's "
3893 "check() or prepare() member, iteration not possible.");
3897 g_atomic_int_inc (&loop->ref_count);
3898 loop->is_running = TRUE;
3899 while (loop->is_running)
3900 g_main_context_iterate (loop->context, TRUE, TRUE, self);
3902 UNLOCK_CONTEXT (loop->context);
3904 g_main_context_release (loop->context);
3906 g_main_loop_unref (loop);
3911 * @loop: a #GMainLoop
3913 * Stops a #GMainLoop from running. Any calls to g_main_loop_run()
3914 * for the loop will return.
3916 * Note that sources that have already been dispatched when
3917 * g_main_loop_quit() is called will still be executed.
3920 g_main_loop_quit (GMainLoop *loop)
3922 g_return_if_fail (loop != NULL);
3923 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3925 LOCK_CONTEXT (loop->context);
3926 loop->is_running = FALSE;
3927 g_wakeup_signal (loop->context->wakeup);
3929 g_cond_broadcast (&loop->context->cond);
3931 UNLOCK_CONTEXT (loop->context);
3935 * g_main_loop_is_running:
3936 * @loop: a #GMainLoop.
3938 * Checks to see if the main loop is currently being run via g_main_loop_run().
3940 * Return value: %TRUE if the mainloop is currently being run.
3943 g_main_loop_is_running (GMainLoop *loop)
3945 g_return_val_if_fail (loop != NULL, FALSE);
3946 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, FALSE);
3948 return loop->is_running;
3952 * g_main_loop_get_context:
3953 * @loop: a #GMainLoop.
3955 * Returns the #GMainContext of @loop.
3957 * Return value: (transfer none): the #GMainContext of @loop
3960 g_main_loop_get_context (GMainLoop *loop)
3962 g_return_val_if_fail (loop != NULL, NULL);
3963 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
3965 return loop->context;
3968 /* HOLDS: context's lock */
3970 g_main_context_poll (GMainContext *context,
3976 #ifdef G_MAIN_POLL_DEBUG
3982 GPollFunc poll_func;
3984 if (n_fds || timeout != 0)
3986 #ifdef G_MAIN_POLL_DEBUG
3987 if (_g_main_poll_debug)
3989 g_print ("polling context=%p n=%d timeout=%d\n",
3990 context, n_fds, timeout);
3991 poll_timer = g_timer_new ();
3995 LOCK_CONTEXT (context);
3997 poll_func = context->poll_func;
3999 UNLOCK_CONTEXT (context);
4000 if ((*poll_func) (fds, n_fds, timeout) < 0 && errno != EINTR)
4003 g_warning ("poll(2) failed due to: %s.",
4004 g_strerror (errno));
4006 /* If g_poll () returns -1, it has already called g_warning() */
4010 #ifdef G_MAIN_POLL_DEBUG
4011 if (_g_main_poll_debug)
4013 LOCK_CONTEXT (context);
4015 g_print ("g_main_poll(%d) timeout: %d - elapsed %12.10f seconds",
4018 g_timer_elapsed (poll_timer, NULL));
4019 g_timer_destroy (poll_timer);
4020 pollrec = context->poll_records;
4022 while (pollrec != NULL)
4027 if (fds[i].fd == pollrec->fd->fd &&
4028 pollrec->fd->events &&
4031 g_print (" [" G_POLLFD_FORMAT " :", fds[i].fd);
4032 if (fds[i].revents & G_IO_IN)
4034 if (fds[i].revents & G_IO_OUT)
4036 if (fds[i].revents & G_IO_PRI)
4038 if (fds[i].revents & G_IO_ERR)
4040 if (fds[i].revents & G_IO_HUP)
4042 if (fds[i].revents & G_IO_NVAL)
4048 pollrec = pollrec->next;
4052 UNLOCK_CONTEXT (context);
4055 } /* if (n_fds || timeout != 0) */
4059 * g_main_context_add_poll:
4060 * @context: (allow-none): a #GMainContext (or %NULL for the default context)
4061 * @fd: a #GPollFD structure holding information about a file
4062 * descriptor to watch.
4063 * @priority: the priority for this file descriptor which should be
4064 * the same as the priority used for g_source_attach() to ensure that the
4065 * file descriptor is polled whenever the results may be needed.
4067 * Adds a file descriptor to the set of file descriptors polled for
4068 * this context. This will very seldom be used directly. Instead
4069 * a typical event source will use g_source_add_unix_fd() instead.
4072 g_main_context_add_poll (GMainContext *context,
4077 context = g_main_context_default ();
4079 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
4080 g_return_if_fail (fd);
4082 LOCK_CONTEXT (context);
4083 g_main_context_add_poll_unlocked (context, priority, fd);
4084 UNLOCK_CONTEXT (context);
4087 /* HOLDS: main_loop_lock */
4089 g_main_context_add_poll_unlocked (GMainContext *context,
4093 GPollRec *prevrec, *nextrec;
4094 GPollRec *newrec = g_slice_new (GPollRec);
4096 /* This file descriptor may be checked before we ever poll */
4099 newrec->priority = priority;
4101 prevrec = context->poll_records_tail;
4103 while (prevrec && priority < prevrec->priority)
4106 prevrec = prevrec->prev;
4110 prevrec->next = newrec;
4112 context->poll_records = newrec;
4114 newrec->prev = prevrec;
4115 newrec->next = nextrec;
4118 nextrec->prev = newrec;
4120 context->poll_records_tail = newrec;
4122 context->n_poll_records++;
4124 context->poll_changed = TRUE;
4126 /* Now wake up the main loop if it is waiting in the poll() */
4127 g_wakeup_signal (context->wakeup);
4131 * g_main_context_remove_poll:
4132 * @context:a #GMainContext
4133 * @fd: a #GPollFD descriptor previously added with g_main_context_add_poll()
4135 * Removes file descriptor from the set of file descriptors to be
4136 * polled for a particular context.
4139 g_main_context_remove_poll (GMainContext *context,
4143 context = g_main_context_default ();
4145 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
4146 g_return_if_fail (fd);
4148 LOCK_CONTEXT (context);
4149 g_main_context_remove_poll_unlocked (context, fd);
4150 UNLOCK_CONTEXT (context);
4154 g_main_context_remove_poll_unlocked (GMainContext *context,
4157 GPollRec *pollrec, *prevrec, *nextrec;
4160 pollrec = context->poll_records;
4164 nextrec = pollrec->next;
4165 if (pollrec->fd == fd)
4167 if (prevrec != NULL)
4168 prevrec->next = nextrec;
4170 context->poll_records = nextrec;
4172 if (nextrec != NULL)
4173 nextrec->prev = prevrec;
4175 context->poll_records_tail = prevrec;
4177 g_slice_free (GPollRec, pollrec);
4179 context->n_poll_records--;
4186 context->poll_changed = TRUE;
4188 /* Now wake up the main loop if it is waiting in the poll() */
4189 g_wakeup_signal (context->wakeup);
4193 * g_source_get_current_time:
4194 * @source: a #GSource
4195 * @timeval: #GTimeVal structure in which to store current time.
4197 * This function ignores @source and is otherwise the same as
4198 * g_get_current_time().
4200 * Deprecated: 2.28: use g_source_get_time() instead
4203 g_source_get_current_time (GSource *source,
4206 g_get_current_time (timeval);
4210 * g_source_get_time:
4211 * @source: a #GSource
4213 * Gets the time to be used when checking this source. The advantage of
4214 * calling this function over calling g_get_monotonic_time() directly is
4215 * that when checking multiple sources, GLib can cache a single value
4216 * instead of having to repeatedly get the system monotonic time.
4218 * The time here is the system monotonic time, if available, or some
4219 * other reasonable alternative otherwise. See g_get_monotonic_time().
4221 * Returns: the monotonic time in microseconds
4226 g_source_get_time (GSource *source)
4228 GMainContext *context;
4231 g_return_val_if_fail (source->context != NULL, 0);
4233 context = source->context;
4235 LOCK_CONTEXT (context);
4237 if (!context->time_is_fresh)
4239 context->time = g_get_monotonic_time ();
4240 context->time_is_fresh = TRUE;
4243 result = context->time;
4245 UNLOCK_CONTEXT (context);
4251 * g_main_context_set_poll_func:
4252 * @context: a #GMainContext
4253 * @func: the function to call to poll all file descriptors
4255 * Sets the function to use to handle polling of file descriptors. It
4256 * will be used instead of the poll() system call
4257 * (or GLib's replacement function, which is used where
4258 * poll() isn't available).
4260 * This function could possibly be used to integrate the GLib event
4261 * loop with an external event loop.
4264 g_main_context_set_poll_func (GMainContext *context,
4268 context = g_main_context_default ();
4270 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
4272 LOCK_CONTEXT (context);
4275 context->poll_func = func;
4277 context->poll_func = g_poll;
4279 UNLOCK_CONTEXT (context);
4283 * g_main_context_get_poll_func:
4284 * @context: a #GMainContext
4286 * Gets the poll function set by g_main_context_set_poll_func().
4288 * Return value: the poll function
4291 g_main_context_get_poll_func (GMainContext *context)
4296 context = g_main_context_default ();
4298 g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL);
4300 LOCK_CONTEXT (context);
4301 result = context->poll_func;
4302 UNLOCK_CONTEXT (context);
4308 * g_main_context_wakeup:
4309 * @context: a #GMainContext
4311 * If @context is currently blocking in g_main_context_iteration()
4312 * waiting for a source to become ready, cause it to stop blocking
4313 * and return. Otherwise, cause the next invocation of
4314 * g_main_context_iteration() to return without blocking.
4316 * This API is useful for low-level control over #GMainContext; for
4317 * example, integrating it with main loop implementations such as
4320 * Another related use for this function is when implementing a main
4321 * loop with a termination condition, computed from multiple threads:
4324 * #define NUM_TASKS 10
4325 * static volatile gint tasks_remaining = NUM_TASKS;
4328 * while (g_atomic_int_get (&tasks_remaining) != 0)
4329 * g_main_context_iteration (NULL, TRUE);
4336 * if (g_atomic_int_dec_and_test (&tasks_remaining))
4337 * g_main_context_wakeup (NULL);
4341 g_main_context_wakeup (GMainContext *context)
4344 context = g_main_context_default ();
4346 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
4348 g_wakeup_signal (context->wakeup);
4352 * g_main_context_is_owner:
4353 * @context: a #GMainContext
4355 * Determines whether this thread holds the (recursive)
4356 * ownership of this #GMainContext. This is useful to
4357 * know before waiting on another thread that may be
4358 * blocking to get ownership of @context.
4360 * Returns: %TRUE if current thread is owner of @context.
4365 g_main_context_is_owner (GMainContext *context)
4370 context = g_main_context_default ();
4372 LOCK_CONTEXT (context);
4373 is_owner = context->owner == G_THREAD_SELF;
4374 UNLOCK_CONTEXT (context);
4382 g_timeout_set_expiration (GTimeoutSource *timeout_source,
4383 gint64 current_time)
4387 expiration = current_time + (guint64) timeout_source->interval * 1000;
4389 if (timeout_source->seconds)
4392 static gint timer_perturb = -1;
4394 if (timer_perturb == -1)
4397 * we want a per machine/session unique 'random' value; try the dbus
4398 * address first, that has a UUID in it. If there is no dbus, use the
4399 * hostname for hashing.
4401 const char *session_bus_address = g_getenv ("DBUS_SESSION_BUS_ADDRESS");
4402 if (!session_bus_address)
4403 session_bus_address = g_getenv ("HOSTNAME");
4404 if (session_bus_address)
4405 timer_perturb = ABS ((gint) g_str_hash (session_bus_address)) % 1000000;
4410 /* We want the microseconds part of the timeout to land on the
4411 * 'timer_perturb' mark, but we need to make sure we don't try to
4412 * set the timeout in the past. We do this by ensuring that we
4413 * always only *increase* the expiration time by adding a full
4414 * second in the case that the microsecond portion decreases.
4416 expiration -= timer_perturb;
4418 remainder = expiration % 1000000;
4419 if (remainder >= 1000000/4)
4420 expiration += 1000000;
4422 expiration -= remainder;
4423 expiration += timer_perturb;
4426 g_source_set_ready_time ((GSource *) timeout_source, expiration);
4430 g_timeout_dispatch (GSource *source,
4431 GSourceFunc callback,
4434 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
4439 g_warning ("Timeout source dispatched without callback\n"
4440 "You must call g_source_set_callback().");
4444 again = callback (user_data);
4447 g_timeout_set_expiration (timeout_source, g_source_get_time (source));
4453 * g_timeout_source_new:
4454 * @interval: the timeout interval in milliseconds.
4456 * Creates a new timeout source.
4458 * The source will not initially be associated with any #GMainContext
4459 * and must be added to one with g_source_attach() before it will be
4462 * The interval given is in terms of monotonic time, not wall clock
4463 * time. See g_get_monotonic_time().
4465 * Return value: the newly-created timeout source
4468 g_timeout_source_new (guint interval)
4470 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
4471 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
4473 timeout_source->interval = interval;
4474 g_timeout_set_expiration (timeout_source, g_get_monotonic_time ());
4480 * g_timeout_source_new_seconds:
4481 * @interval: the timeout interval in seconds
4483 * Creates a new timeout source.
4485 * The source will not initially be associated with any #GMainContext
4486 * and must be added to one with g_source_attach() before it will be
4489 * The scheduling granularity/accuracy of this timeout source will be
4492 * The interval given in terms of monotonic time, not wall clock time.
4493 * See g_get_monotonic_time().
4495 * Return value: the newly-created timeout source
4500 g_timeout_source_new_seconds (guint interval)
4502 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
4503 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
4505 timeout_source->interval = 1000 * interval;
4506 timeout_source->seconds = TRUE;
4508 g_timeout_set_expiration (timeout_source, g_get_monotonic_time ());
4515 * g_timeout_add_full:
4516 * @priority: the priority of the timeout source. Typically this will be in
4517 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
4518 * @interval: the time between calls to the function, in milliseconds
4519 * (1/1000ths of a second)
4520 * @function: function to call
4521 * @data: data to pass to @function
4522 * @notify: (allow-none): function to call when the timeout is removed, or %NULL
4524 * Sets a function to be called at regular intervals, with the given
4525 * priority. The function is called repeatedly until it returns
4526 * %FALSE, at which point the timeout is automatically destroyed and
4527 * the function will not be called again. The @notify function is
4528 * called when the timeout is destroyed. The first call to the
4529 * function will be at the end of the first @interval.
4531 * Note that timeout functions may be delayed, due to the processing of other
4532 * event sources. Thus they should not be relied on for precise timing.
4533 * After each call to the timeout function, the time of the next
4534 * timeout is recalculated based on the current time and the given interval
4535 * (it does not try to 'catch up' time lost in delays).
4537 * This internally creates a main loop source using g_timeout_source_new()
4538 * and attaches it to the main loop context using g_source_attach(). You can
4539 * do these steps manually if you need greater control.
4541 * The interval given in terms of monotonic time, not wall clock time.
4542 * See g_get_monotonic_time().
4544 * Return value: the ID (greater than 0) of the event source.
4545 * Rename to: g_timeout_add
4548 g_timeout_add_full (gint priority,
4550 GSourceFunc function,
4552 GDestroyNotify notify)
4557 g_return_val_if_fail (function != NULL, 0);
4559 source = g_timeout_source_new (interval);
4561 if (priority != G_PRIORITY_DEFAULT)
4562 g_source_set_priority (source, priority);
4564 g_source_set_callback (source, function, data, notify);
4565 id = g_source_attach (source, NULL);
4566 g_source_unref (source);
4573 * @interval: the time between calls to the function, in milliseconds
4574 * (1/1000ths of a second)
4575 * @function: function to call
4576 * @data: data to pass to @function
4578 * Sets a function to be called at regular intervals, with the default
4579 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly
4580 * until it returns %FALSE, at which point the timeout is automatically
4581 * destroyed and the function will not be called again. The first call
4582 * to the function will be at the end of the first @interval.
4584 * Note that timeout functions may be delayed, due to the processing of other
4585 * event sources. Thus they should not be relied on for precise timing.
4586 * After each call to the timeout function, the time of the next
4587 * timeout is recalculated based on the current time and the given interval
4588 * (it does not try to 'catch up' time lost in delays).
4590 * If you want to have a timer in the "seconds" range and do not care
4591 * about the exact time of the first call of the timer, use the
4592 * g_timeout_add_seconds() function; this function allows for more
4593 * optimizations and more efficient system power usage.
4595 * This internally creates a main loop source using g_timeout_source_new()
4596 * and attaches it to the main loop context using g_source_attach(). You can
4597 * do these steps manually if you need greater control.
4599 * The interval given is in terms of monotonic time, not wall clock
4600 * time. See g_get_monotonic_time().
4602 * Return value: the ID (greater than 0) of the event source.
4605 g_timeout_add (guint32 interval,
4606 GSourceFunc function,
4609 return g_timeout_add_full (G_PRIORITY_DEFAULT,
4610 interval, function, data, NULL);
4614 * g_timeout_add_seconds_full:
4615 * @priority: the priority of the timeout source. Typically this will be in
4616 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
4617 * @interval: the time between calls to the function, in seconds
4618 * @function: function to call
4619 * @data: data to pass to @function
4620 * @notify: (allow-none): function to call when the timeout is removed, or %NULL
4622 * Sets a function to be called at regular intervals, with @priority.
4623 * The function is called repeatedly until it returns %FALSE, at which
4624 * point the timeout is automatically destroyed and the function will
4625 * not be called again.
4627 * Unlike g_timeout_add(), this function operates at whole second granularity.
4628 * The initial starting point of the timer is determined by the implementation
4629 * and the implementation is expected to group multiple timers together so that
4630 * they fire all at the same time.
4631 * To allow this grouping, the @interval to the first timer is rounded
4632 * and can deviate up to one second from the specified interval.
4633 * Subsequent timer iterations will generally run at the specified interval.
4635 * Note that timeout functions may be delayed, due to the processing of other
4636 * event sources. Thus they should not be relied on for precise timing.
4637 * After each call to the timeout function, the time of the next
4638 * timeout is recalculated based on the current time and the given @interval
4640 * If you want timing more precise than whole seconds, use g_timeout_add()
4643 * The grouping of timers to fire at the same time results in a more power
4644 * and CPU efficient behavior so if your timer is in multiples of seconds
4645 * and you don't require the first timer exactly one second from now, the
4646 * use of g_timeout_add_seconds() is preferred over g_timeout_add().
4648 * This internally creates a main loop source using
4649 * g_timeout_source_new_seconds() and attaches it to the main loop context
4650 * using g_source_attach(). You can do these steps manually if you need
4653 * The interval given is in terms of monotonic time, not wall clock
4654 * time. See g_get_monotonic_time().
4656 * Return value: the ID (greater than 0) of the event source.
4658 * Rename to: g_timeout_add_seconds
4662 g_timeout_add_seconds_full (gint priority,
4664 GSourceFunc function,
4666 GDestroyNotify notify)
4671 g_return_val_if_fail (function != NULL, 0);
4673 source = g_timeout_source_new_seconds (interval);
4675 if (priority != G_PRIORITY_DEFAULT)
4676 g_source_set_priority (source, priority);
4678 g_source_set_callback (source, function, data, notify);
4679 id = g_source_attach (source, NULL);
4680 g_source_unref (source);
4686 * g_timeout_add_seconds:
4687 * @interval: the time between calls to the function, in seconds
4688 * @function: function to call
4689 * @data: data to pass to @function
4691 * Sets a function to be called at regular intervals with the default
4692 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly until
4693 * it returns %FALSE, at which point the timeout is automatically destroyed
4694 * and the function will not be called again.
4696 * This internally creates a main loop source using
4697 * g_timeout_source_new_seconds() and attaches it to the main loop context
4698 * using g_source_attach(). You can do these steps manually if you need
4699 * greater control. Also see g_timeout_add_seconds_full().
4701 * Note that the first call of the timer may not be precise for timeouts
4702 * of one second. If you need finer precision and have such a timeout,
4703 * you may want to use g_timeout_add() instead.
4705 * The interval given is in terms of monotonic time, not wall clock
4706 * time. See g_get_monotonic_time().
4708 * Return value: the ID (greater than 0) of the event source.
4713 g_timeout_add_seconds (guint interval,
4714 GSourceFunc function,
4717 g_return_val_if_fail (function != NULL, 0);
4719 return g_timeout_add_seconds_full (G_PRIORITY_DEFAULT, interval, function, data, NULL);
4722 /* Child watch functions */
4727 g_child_watch_prepare (GSource *source,
4735 g_child_watch_check (GSource *source)
4737 GChildWatchSource *child_watch_source;
4738 gboolean child_exited;
4740 child_watch_source = (GChildWatchSource *) source;
4742 child_exited = child_watch_source->poll.revents & G_IO_IN;
4749 * Note: We do _not_ check for the special value of STILL_ACTIVE
4750 * since we know that the process has exited and doing so runs into
4751 * problems if the child process "happens to return STILL_ACTIVE(259)"
4752 * as Microsoft's Platform SDK puts it.
4754 if (!GetExitCodeProcess (child_watch_source->pid, &child_status))
4756 gchar *emsg = g_win32_error_message (GetLastError ());
4757 g_warning (G_STRLOC ": GetExitCodeProcess() failed: %s", emsg);
4760 child_watch_source->child_status = -1;
4763 child_watch_source->child_status = child_status;
4766 return child_exited;
4770 g_child_watch_finalize (GSource *source)
4774 #else /* G_OS_WIN32 */
4777 wake_source (GSource *source)
4779 GMainContext *context;
4781 /* This should be thread-safe:
4783 * - if the source is currently being added to a context, that
4784 * context will be woken up anyway
4786 * - if the source is currently being destroyed, we simply need not
4789 * - the memory for the source will remain valid until after the
4790 * source finalize function was called (which would remove the
4791 * source from the global list which we are currently holding the
4794 * - the GMainContext will either be NULL or point to a live
4797 * - the GMainContext will remain valid since we hold the
4798 * main_context_list lock
4800 * Since we are holding a lot of locks here, don't try to enter any
4801 * more GMainContext functions for fear of dealock -- just hit the
4802 * GWakeup and run. Even if that's safe now, it could easily become
4803 * unsafe with some very minor changes in the future, and signal
4804 * handling is not the most well-tested codepath.
4806 G_LOCK(main_context_list);
4807 context = source->context;
4809 g_wakeup_signal (context->wakeup);
4810 G_UNLOCK(main_context_list);
4814 dispatch_unix_signals (void)
4818 /* clear this first incase another one arrives while we're processing */
4819 any_unix_signal_pending = FALSE;
4821 G_LOCK(unix_signal_lock);
4823 /* handle GChildWatchSource instances */
4824 if (unix_signal_pending[SIGCHLD])
4826 /* The only way we can do this is to scan all of the children.
4828 * The docs promise that we will not reap children that we are not
4829 * explicitly watching, so that ties our hands from calling
4830 * waitpid(-1). We also can't use siginfo's si_pid field since if
4831 * multiple SIGCHLD arrive at the same time, one of them can be
4832 * dropped (since a given UNIX signal can only be pending once).
4834 for (node = unix_child_watches; node; node = node->next)
4836 GChildWatchSource *source = node->data;
4838 if (!source->child_exited)
4843 pid = waitpid (source->pid, &source->child_status, WNOHANG);
4846 source->child_exited = TRUE;
4847 wake_source ((GSource *) source);
4849 else if (pid == -1 && errno == ECHILD)
4851 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.");
4852 source->child_exited = TRUE;
4853 source->child_status = 0;
4854 wake_source ((GSource *) source);
4857 while (pid == -1 && errno == EINTR);
4862 /* handle GUnixSignalWatchSource instances */
4863 for (node = unix_signal_watches; node; node = node->next)
4865 GUnixSignalWatchSource *source = node->data;
4867 if (!source->pending)
4869 if (unix_signal_pending[source->signum])
4871 source->pending = TRUE;
4873 wake_source ((GSource *) source);
4878 memset ((void*)unix_signal_pending, 0, sizeof (unix_signal_pending));
4880 G_UNLOCK(unix_signal_lock);
4884 g_child_watch_prepare (GSource *source,
4887 GChildWatchSource *child_watch_source;
4889 child_watch_source = (GChildWatchSource *) source;
4891 return child_watch_source->child_exited;
4895 g_child_watch_check (GSource *source)
4897 GChildWatchSource *child_watch_source;
4899 child_watch_source = (GChildWatchSource *) source;
4901 return child_watch_source->child_exited;
4905 g_unix_signal_watch_prepare (GSource *source,
4908 GUnixSignalWatchSource *unix_signal_source;
4910 unix_signal_source = (GUnixSignalWatchSource *) source;
4912 return unix_signal_source->pending;
4916 g_unix_signal_watch_check (GSource *source)
4918 GUnixSignalWatchSource *unix_signal_source;
4920 unix_signal_source = (GUnixSignalWatchSource *) source;
4922 return unix_signal_source->pending;
4926 g_unix_signal_watch_dispatch (GSource *source,
4927 GSourceFunc callback,
4930 GUnixSignalWatchSource *unix_signal_source;
4933 unix_signal_source = (GUnixSignalWatchSource *) source;
4937 g_warning ("Unix signal source dispatched without callback\n"
4938 "You must call g_source_set_callback().");
4942 again = (callback) (user_data);
4944 unix_signal_source->pending = FALSE;
4950 ref_unix_signal_handler_unlocked (int signum)
4952 /* Ensure we have the worker context */
4953 g_get_worker_context ();
4954 unix_signal_refcount[signum]++;
4955 if (unix_signal_refcount[signum] == 1)
4957 struct sigaction action;
4958 action.sa_handler = g_unix_signal_handler;
4959 sigemptyset (&action.sa_mask);
4961 action.sa_flags = SA_RESTART | SA_NOCLDSTOP;
4963 action.sa_flags = SA_NOCLDSTOP;
4965 sigaction (signum, &action, NULL);
4970 unref_unix_signal_handler_unlocked (int signum)
4972 unix_signal_refcount[signum]--;
4973 if (unix_signal_refcount[signum] == 0)
4975 struct sigaction action;
4976 memset (&action, 0, sizeof (action));
4977 action.sa_handler = SIG_DFL;
4978 sigemptyset (&action.sa_mask);
4979 sigaction (signum, &action, NULL);
4984 _g_main_create_unix_signal_watch (int signum)
4987 GUnixSignalWatchSource *unix_signal_source;
4989 source = g_source_new (&g_unix_signal_funcs, sizeof (GUnixSignalWatchSource));
4990 unix_signal_source = (GUnixSignalWatchSource *) source;
4992 unix_signal_source->signum = signum;
4993 unix_signal_source->pending = FALSE;
4995 G_LOCK (unix_signal_lock);
4996 ref_unix_signal_handler_unlocked (signum);
4997 unix_signal_watches = g_slist_prepend (unix_signal_watches, unix_signal_source);
4998 if (unix_signal_pending[signum])
4999 unix_signal_source->pending = TRUE;
5000 G_UNLOCK (unix_signal_lock);
5006 g_unix_signal_watch_finalize (GSource *source)
5008 GUnixSignalWatchSource *unix_signal_source;
5010 unix_signal_source = (GUnixSignalWatchSource *) source;
5012 G_LOCK (unix_signal_lock);
5013 unref_unix_signal_handler_unlocked (unix_signal_source->signum);
5014 unix_signal_watches = g_slist_remove (unix_signal_watches, source);
5015 G_UNLOCK (unix_signal_lock);
5019 g_child_watch_finalize (GSource *source)
5021 G_LOCK (unix_signal_lock);
5022 unix_child_watches = g_slist_remove (unix_child_watches, source);
5023 unref_unix_signal_handler_unlocked (SIGCHLD);
5024 G_UNLOCK (unix_signal_lock);
5027 #endif /* G_OS_WIN32 */
5030 g_child_watch_dispatch (GSource *source,
5031 GSourceFunc callback,
5034 GChildWatchSource *child_watch_source;
5035 GChildWatchFunc child_watch_callback = (GChildWatchFunc) callback;
5037 child_watch_source = (GChildWatchSource *) source;
5041 g_warning ("Child watch source dispatched without callback\n"
5042 "You must call g_source_set_callback().");
5046 (child_watch_callback) (child_watch_source->pid, child_watch_source->child_status, user_data);
5048 /* We never keep a child watch source around as the child is gone */
5055 g_unix_signal_handler (int signum)
5057 unix_signal_pending[signum] = TRUE;
5058 any_unix_signal_pending = TRUE;
5060 g_wakeup_signal (glib_worker_context->wakeup);
5063 #endif /* !G_OS_WIN32 */
5066 * g_child_watch_source_new:
5067 * @pid: process to watch. On POSIX the pid of a child process. On
5068 * Windows a handle for a process (which doesn't have to be a child).
5070 * Creates a new child_watch source.
5072 * The source will not initially be associated with any #GMainContext
5073 * and must be added to one with g_source_attach() before it will be
5076 * Note that child watch sources can only be used in conjunction with
5077 * <literal>g_spawn...</literal> when the %G_SPAWN_DO_NOT_REAP_CHILD
5080 * Note that on platforms where #GPid must be explicitly closed
5081 * (see g_spawn_close_pid()) @pid must not be closed while the
5082 * source is still active. Typically, you will want to call
5083 * g_spawn_close_pid() in the callback function for the source.
5085 * Note further that using g_child_watch_source_new() is not
5086 * compatible with calling <literal>waitpid</literal> with a
5087 * nonpositive first argument in the application. Calling waitpid()
5088 * for individual pids will still work fine.
5090 * Return value: the newly-created child watch source
5095 g_child_watch_source_new (GPid pid)
5097 GSource *source = g_source_new (&g_child_watch_funcs, sizeof (GChildWatchSource));
5098 GChildWatchSource *child_watch_source = (GChildWatchSource *)source;
5100 child_watch_source->pid = pid;
5103 child_watch_source->poll.fd = (gintptr) pid;
5104 child_watch_source->poll.events = G_IO_IN;
5106 g_source_add_poll (source, &child_watch_source->poll);
5107 #else /* G_OS_WIN32 */
5108 G_LOCK (unix_signal_lock);
5109 ref_unix_signal_handler_unlocked (SIGCHLD);
5110 unix_child_watches = g_slist_prepend (unix_child_watches, child_watch_source);
5111 if (waitpid (pid, &child_watch_source->child_status, WNOHANG) > 0)
5112 child_watch_source->child_exited = TRUE;
5113 G_UNLOCK (unix_signal_lock);
5114 #endif /* G_OS_WIN32 */
5120 * g_child_watch_add_full:
5121 * @priority: the priority of the idle source. Typically this will be in the
5122 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
5123 * @pid: process to watch. On POSIX the pid of a child process. On
5124 * Windows a handle for a process (which doesn't have to be a child).
5125 * @function: function to call
5126 * @data: data to pass to @function
5127 * @notify: (allow-none): function to call when the idle is removed, or %NULL
5129 * Sets a function to be called when the child indicated by @pid
5130 * exits, at the priority @priority.
5132 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
5133 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
5134 * the spawn function for the child watching to work.
5136 * In many programs, you will want to call g_spawn_check_exit_status()
5137 * in the callback to determine whether or not the child exited
5140 * Also, note that on platforms where #GPid must be explicitly closed
5141 * (see g_spawn_close_pid()) @pid must not be closed while the source
5142 * is still active. Typically, you should invoke g_spawn_close_pid()
5143 * in the callback function for the source.
5145 * GLib supports only a single callback per process id.
5147 * This internally creates a main loop source using
5148 * g_child_watch_source_new() and attaches it to the main loop context
5149 * using g_source_attach(). You can do these steps manually if you
5150 * need greater control.
5152 * Return value: the ID (greater than 0) of the event source.
5154 * Rename to: g_child_watch_add
5158 g_child_watch_add_full (gint priority,
5160 GChildWatchFunc function,
5162 GDestroyNotify notify)
5167 g_return_val_if_fail (function != NULL, 0);
5169 source = g_child_watch_source_new (pid);
5171 if (priority != G_PRIORITY_DEFAULT)
5172 g_source_set_priority (source, priority);
5174 g_source_set_callback (source, (GSourceFunc) function, data, notify);
5175 id = g_source_attach (source, NULL);
5176 g_source_unref (source);
5182 * g_child_watch_add:
5183 * @pid: process id to watch. On POSIX the pid of a child process. On
5184 * Windows a handle for a process (which doesn't have to be a child).
5185 * @function: function to call
5186 * @data: data to pass to @function
5188 * Sets a function to be called when the child indicated by @pid
5189 * exits, at a default priority, #G_PRIORITY_DEFAULT.
5191 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
5192 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
5193 * the spawn function for the child watching to work.
5195 * Note that on platforms where #GPid must be explicitly closed
5196 * (see g_spawn_close_pid()) @pid must not be closed while the
5197 * source is still active. Typically, you will want to call
5198 * g_spawn_close_pid() in the callback function for the source.
5200 * GLib supports only a single callback per process id.
5202 * This internally creates a main loop source using
5203 * g_child_watch_source_new() and attaches it to the main loop context
5204 * using g_source_attach(). You can do these steps manually if you
5205 * need greater control.
5207 * Return value: the ID (greater than 0) of the event source.
5212 g_child_watch_add (GPid pid,
5213 GChildWatchFunc function,
5216 return g_child_watch_add_full (G_PRIORITY_DEFAULT, pid, function, data, NULL);
5220 /* Idle functions */
5223 g_idle_prepare (GSource *source,
5232 g_idle_check (GSource *source)
5238 g_idle_dispatch (GSource *source,
5239 GSourceFunc callback,
5244 g_warning ("Idle source dispatched without callback\n"
5245 "You must call g_source_set_callback().");
5249 return callback (user_data);
5253 * g_idle_source_new:
5255 * Creates a new idle source.
5257 * The source will not initially be associated with any #GMainContext
5258 * and must be added to one with g_source_attach() before it will be
5259 * executed. Note that the default priority for idle sources is
5260 * %G_PRIORITY_DEFAULT_IDLE, as compared to other sources which
5261 * have a default priority of %G_PRIORITY_DEFAULT.
5263 * Return value: the newly-created idle source
5266 g_idle_source_new (void)
5270 source = g_source_new (&g_idle_funcs, sizeof (GSource));
5271 g_source_set_priority (source, G_PRIORITY_DEFAULT_IDLE);
5278 * @priority: the priority of the idle source. Typically this will be in the
5279 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
5280 * @function: function to call
5281 * @data: data to pass to @function
5282 * @notify: (allow-none): function to call when the idle is removed, or %NULL
5284 * Adds a function to be called whenever there are no higher priority
5285 * events pending. If the function returns %FALSE it is automatically
5286 * removed from the list of event sources and will not be called again.
5288 * This internally creates a main loop source using g_idle_source_new()
5289 * and attaches it to the main loop context using g_source_attach().
5290 * You can do these steps manually if you need greater control.
5292 * Return value: the ID (greater than 0) of the event source.
5293 * Rename to: g_idle_add
5296 g_idle_add_full (gint priority,
5297 GSourceFunc function,
5299 GDestroyNotify notify)
5304 g_return_val_if_fail (function != NULL, 0);
5306 source = g_idle_source_new ();
5308 if (priority != G_PRIORITY_DEFAULT_IDLE)
5309 g_source_set_priority (source, priority);
5311 g_source_set_callback (source, function, data, notify);
5312 id = g_source_attach (source, NULL);
5313 g_source_unref (source);
5320 * @function: function to call
5321 * @data: data to pass to @function.
5323 * Adds a function to be called whenever there are no higher priority
5324 * events pending to the default main loop. The function is given the
5325 * default idle priority, #G_PRIORITY_DEFAULT_IDLE. If the function
5326 * returns %FALSE it is automatically removed from the list of event
5327 * sources and will not be called again.
5329 * This internally creates a main loop source using g_idle_source_new()
5330 * and attaches it to the main loop context using g_source_attach().
5331 * You can do these steps manually if you need greater control.
5333 * Return value: the ID (greater than 0) of the event source.
5336 g_idle_add (GSourceFunc function,
5339 return g_idle_add_full (G_PRIORITY_DEFAULT_IDLE, function, data, NULL);
5343 * g_idle_remove_by_data:
5344 * @data: the data for the idle source's callback.
5346 * Removes the idle function with the given data.
5348 * Return value: %TRUE if an idle source was found and removed.
5351 g_idle_remove_by_data (gpointer data)
5353 return g_source_remove_by_funcs_user_data (&g_idle_funcs, data);
5357 * g_main_context_invoke:
5358 * @context: (allow-none): a #GMainContext, or %NULL
5359 * @function: function to call
5360 * @data: data to pass to @function
5362 * Invokes a function in such a way that @context is owned during the
5363 * invocation of @function.
5365 * If @context is %NULL then the global default main context — as
5366 * returned by g_main_context_default() — is used.
5368 * If @context is owned by the current thread, @function is called
5369 * directly. Otherwise, if @context is the thread-default main context
5370 * of the current thread and g_main_context_acquire() succeeds, then
5371 * @function is called and g_main_context_release() is called
5374 * In any other case, an idle source is created to call @function and
5375 * that source is attached to @context (presumably to be run in another
5376 * thread). The idle source is attached with #G_PRIORITY_DEFAULT
5377 * priority. If you want a different priority, use
5378 * g_main_context_invoke_full().
5380 * Note that, as with normal idle functions, @function should probably
5381 * return %FALSE. If it returns %TRUE, it will be continuously run in a
5382 * loop (and may prevent this call from returning).
5387 g_main_context_invoke (GMainContext *context,
5388 GSourceFunc function,
5391 g_main_context_invoke_full (context,
5393 function, data, NULL);
5397 * g_main_context_invoke_full:
5398 * @context: (allow-none): a #GMainContext, or %NULL
5399 * @priority: the priority at which to run @function
5400 * @function: function to call
5401 * @data: data to pass to @function
5402 * @notify: (allow-none): a function to call when @data is no longer in use, or %NULL.
5404 * Invokes a function in such a way that @context is owned during the
5405 * invocation of @function.
5407 * This function is the same as g_main_context_invoke() except that it
5408 * lets you specify the priority incase @function ends up being
5409 * scheduled as an idle and also lets you give a #GDestroyNotify for @data.
5411 * @notify should not assume that it is called from any particular
5412 * thread or with any particular context acquired.
5417 g_main_context_invoke_full (GMainContext *context,
5419 GSourceFunc function,
5421 GDestroyNotify notify)
5423 g_return_if_fail (function != NULL);
5426 context = g_main_context_default ();
5428 if (g_main_context_is_owner (context))
5430 while (function (data));
5437 GMainContext *thread_default;
5439 thread_default = g_main_context_get_thread_default ();
5441 if (!thread_default)
5442 thread_default = g_main_context_default ();
5444 if (thread_default == context && g_main_context_acquire (context))
5446 while (function (data));
5448 g_main_context_release (context);
5457 source = g_idle_source_new ();
5458 g_source_set_priority (source, priority);
5459 g_source_set_callback (source, function, data, notify);
5460 g_source_attach (source, context);
5461 g_source_unref (source);
5467 glib_worker_main (gpointer data)
5471 g_main_context_iteration (glib_worker_context, TRUE);
5474 if (any_unix_signal_pending)
5475 dispatch_unix_signals ();
5479 return NULL; /* worst GCC warning message ever... */
5483 g_get_worker_context (void)
5485 static gsize initialised;
5487 if (g_once_init_enter (&initialised))
5489 /* mask all signals in the worker thread */
5495 pthread_sigmask (SIG_SETMASK, &all, &prev_mask);
5497 glib_worker_context = g_main_context_new ();
5498 g_thread_new ("gmain", glib_worker_main, NULL);
5500 pthread_sigmask (SIG_SETMASK, &prev_mask, NULL);
5502 g_once_init_leave (&initialised, TRUE);
5505 return glib_worker_context;