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 /* for pipe2; need to define it first to avoid
36 * other headers pulling in unistd.h
38 /* The meaning of_GNU_SOURCE that is intended here is present only on
39 * Linux; avoid the possibility that some misguided header in MinGW
40 * looks at it. Ideally we should define _GNU_SOURCE only on platforms
41 * where we know what it means and that is what we want here
42 * (i.e. Linux with glibc). After all, there might be some other POSIX
43 * platform even where _GNU_SOURCE is used for some unrelated change
44 * in semantics that isn't wanted. Sigh.
50 #include "glibconfig.h"
52 /* Uncomment the next line (and the corresponding line in gpoll.c) to
53 * enable debugging printouts if the environment variable
54 * G_MAIN_POLL_DEBUG is set to some value.
56 /* #define G_MAIN_POLL_DEBUG */
59 /* Always enable debugging printout on Windows, as it is more often
62 #define G_MAIN_POLL_DEBUG
66 #include <sys/types.h>
69 #ifdef HAVE_SYS_TIME_H
71 #endif /* HAVE_SYS_TIME_H */
74 #endif /* HAVE_UNISTD_H */
80 #endif /* G_OS_WIN32 */
83 #include <sys/socket.h>
85 #endif /* G_OS_BEOS */
95 #include "giochannel.h"
99 #include "gstrfuncs.h"
100 #include "gtestutils.h"
101 #include "gthreadprivate.h"
107 #ifdef G_MAIN_POLL_DEBUG
113 * @title: The Main Event Loop
114 * @short_description: manages all available sources of events
116 * The main event loop manages all the available sources of events for
117 * GLib and GTK+ applications. These events can come from any number of
118 * different types of sources such as file descriptors (plain files,
119 * pipes or sockets) and timeouts. New types of event sources can also
120 * be added using g_source_attach().
122 * To allow multiple independent sets of sources to be handled in
123 * different threads, each source is associated with a #GMainContext.
124 * A GMainContext can only be running in a single thread, but
125 * sources can be added to it and removed from it from other threads.
127 * Each event source is assigned a priority. The default priority,
128 * #G_PRIORITY_DEFAULT, is 0. Values less than 0 denote higher priorities.
129 * Values greater than 0 denote lower priorities. Events from high priority
130 * sources are always processed before events from lower priority sources.
132 * Idle functions can also be added, and assigned a priority. These will
133 * be run whenever no events with a higher priority are ready to be processed.
135 * The #GMainLoop data type represents a main event loop. A GMainLoop is
136 * created with g_main_loop_new(). After adding the initial event sources,
137 * g_main_loop_run() is called. This continuously checks for new events from
138 * each of the event sources and dispatches them. Finally, the processing of
139 * an event from one of the sources leads to a call to g_main_loop_quit() to
140 * exit the main loop, and g_main_loop_run() returns.
142 * It is possible to create new instances of #GMainLoop recursively.
143 * This is often used in GTK+ applications when showing modal dialog
144 * boxes. Note that event sources are associated with a particular
145 * #GMainContext, and will be checked and dispatched for all main
146 * loops associated with that GMainContext.
148 * GTK+ contains wrappers of some of these functions, e.g. gtk_main(),
149 * gtk_main_quit() and gtk_events_pending().
151 * <refsect2><title>Creating new source types</title>
152 * <para>One of the unusual features of the #GMainLoop functionality
153 * is that new types of event source can be created and used in
154 * addition to the builtin type of event source. A new event source
155 * type is used for handling GDK events. A new source type is created
156 * by <firstterm>deriving</firstterm> from the #GSource structure.
157 * The derived type of source is represented by a structure that has
158 * the #GSource structure as a first element, and other elements specific
159 * to the new source type. To create an instance of the new source type,
160 * call g_source_new() passing in the size of the derived structure and
161 * a table of functions. These #GSourceFuncs determine the behavior of
162 * the new source type.</para>
163 * <para>New source types basically interact with the main context
164 * in two ways. Their prepare function in #GSourceFuncs can set a timeout
165 * to determine the maximum amount of time that the main loop will sleep
166 * before checking the source again. In addition, or as well, the source
167 * can add file descriptors to the set that the main context checks using
168 * g_source_add_poll().</para>
170 * <refsect2><title>Customizing the main loop iteration</title>
171 * <para>Single iterations of a #GMainContext can be run with
172 * g_main_context_iteration(). In some cases, more detailed control
173 * of exactly how the details of the main loop work is desired, for
174 * instance, when integrating the #GMainLoop with an external main loop.
175 * In such cases, you can call the component functions of
176 * g_main_context_iteration() directly. These functions are
177 * g_main_context_prepare(), g_main_context_query(),
178 * g_main_context_check() and g_main_context_dispatch().</para>
179 * <para>The operation of these functions can best be seen in terms
180 * of a state diagram, as shown in <xref linkend="mainloop-states"/>.</para>
181 * <figure id="mainloop-states"><title>States of a Main Context</title>
182 * <graphic fileref="mainloop-states.gif" format="GIF"></graphic>
189 typedef struct _GTimeoutSource GTimeoutSource;
190 typedef struct _GChildWatchSource GChildWatchSource;
191 typedef struct _GPollRec GPollRec;
192 typedef struct _GSourceCallback GSourceCallback;
196 G_SOURCE_READY = 1 << G_HOOK_FLAG_USER_SHIFT,
197 G_SOURCE_CAN_RECURSE = 1 << (G_HOOK_FLAG_USER_SHIFT + 1)
200 #ifdef G_THREADS_ENABLED
201 typedef struct _GMainWaiter GMainWaiter;
210 typedef struct _GMainDispatch GMainDispatch;
212 struct _GMainDispatch
215 GSList *dispatching_sources; /* stack of current sources */
218 #ifdef G_MAIN_POLL_DEBUG
219 gboolean _g_main_poll_debug = FALSE;
224 #ifdef G_THREADS_ENABLED
225 /* The following lock is used for both the list of sources
226 * and the list of poll records
237 GPtrArray *pending_dispatches;
238 gint timeout; /* Timeout for current iteration */
241 GSource *source_list;
242 gint in_check_or_prepare;
244 GPollRec *poll_records;
245 guint n_poll_records;
246 GPollFD *cached_poll_array;
247 guint cached_poll_array_size;
249 #ifdef G_THREADS_ENABLED
251 /* this pipe is used to wake up the main loop when a source is added.
253 gint wake_up_pipe[2];
254 #else /* G_OS_WIN32 */
255 HANDLE wake_up_semaphore;
256 #endif /* G_OS_WIN32 */
259 gboolean poll_waiting;
261 /* Flag indicating whether the set of fd's changed during a poll */
262 gboolean poll_changed;
263 #endif /* G_THREADS_ENABLED */
268 gboolean time_is_fresh;
269 GTimeVal current_time;
270 gboolean current_time_is_fresh;
273 struct _GSourceCallback
278 GDestroyNotify notify;
283 GMainContext *context;
288 struct _GTimeoutSource
296 struct _GChildWatchSource
303 #else /* G_OS_WIN32 */
305 gboolean child_exited;
306 #endif /* G_OS_WIN32 */
316 #ifdef G_THREADS_ENABLED
317 #define LOCK_CONTEXT(context) g_static_mutex_lock (&context->mutex)
318 #define UNLOCK_CONTEXT(context) g_static_mutex_unlock (&context->mutex)
319 #define G_THREAD_SELF g_thread_self ()
321 #define LOCK_CONTEXT(context) (void)0
322 #define UNLOCK_CONTEXT(context) (void)0
323 #define G_THREAD_SELF NULL
326 #define SOURCE_DESTROYED(source) (((source)->flags & G_HOOK_FLAG_ACTIVE) == 0)
327 #define SOURCE_BLOCKED(source) (((source)->flags & G_HOOK_FLAG_IN_CALL) != 0 && \
328 ((source)->flags & G_SOURCE_CAN_RECURSE) == 0)
330 #define SOURCE_UNREF(source, context) \
332 if ((source)->ref_count > 1) \
333 (source)->ref_count--; \
335 g_source_unref_internal ((source), (context), TRUE); \
339 /* Forward declarations */
341 static void g_source_unref_internal (GSource *source,
342 GMainContext *context,
344 static void g_source_destroy_internal (GSource *source,
345 GMainContext *context,
347 static void g_main_context_poll (GMainContext *context,
352 static void g_main_context_add_poll_unlocked (GMainContext *context,
355 static void g_main_context_remove_poll_unlocked (GMainContext *context,
357 static void g_main_context_wakeup_unlocked (GMainContext *context);
359 static gboolean g_timeout_prepare (GSource *source,
361 static gboolean g_timeout_check (GSource *source);
362 static gboolean g_timeout_dispatch (GSource *source,
363 GSourceFunc callback,
365 static gboolean g_child_watch_prepare (GSource *source,
367 static gboolean g_child_watch_check (GSource *source);
368 static gboolean g_child_watch_dispatch (GSource *source,
369 GSourceFunc callback,
371 static gboolean g_idle_prepare (GSource *source,
373 static gboolean g_idle_check (GSource *source);
374 static gboolean g_idle_dispatch (GSource *source,
375 GSourceFunc callback,
378 G_LOCK_DEFINE_STATIC (main_loop);
379 static GMainContext *default_main_context;
380 static GSList *main_contexts_without_pipe = NULL;
383 /* Child status monitoring code */
385 CHILD_WATCH_UNINITIALIZED,
386 CHILD_WATCH_INITIALIZED_SINGLE,
387 CHILD_WATCH_INITIALIZED_THREADED
389 static gint child_watch_init_state = CHILD_WATCH_UNINITIALIZED;
390 static gint child_watch_count = 1;
391 static gint child_watch_wake_up_pipe[2] = {0, 0};
392 #endif /* !G_OS_WIN32 */
393 G_LOCK_DEFINE_STATIC (main_context_list);
394 static GSList *main_context_list = NULL;
396 GSourceFuncs g_timeout_funcs =
404 GSourceFuncs g_child_watch_funcs =
406 g_child_watch_prepare,
408 g_child_watch_dispatch,
412 GSourceFuncs g_idle_funcs =
421 * g_main_context_ref:
422 * @context: a #GMainContext
424 * Increases the reference count on a #GMainContext object by one.
426 * Returns: the @context that was passed in (since 2.6)
429 g_main_context_ref (GMainContext *context)
431 g_return_val_if_fail (context != NULL, NULL);
432 g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL);
434 g_atomic_int_inc (&context->ref_count);
440 poll_rec_list_free (GMainContext *context,
443 g_slice_free_chain (GPollRec, list, next);
447 * g_main_context_unref:
448 * @context: a #GMainContext
450 * Decreases the reference count on a #GMainContext object by one. If
451 * the result is zero, free the context and free all associated memory.
454 g_main_context_unref (GMainContext *context)
457 g_return_if_fail (context != NULL);
458 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
460 if (!g_atomic_int_dec_and_test (&context->ref_count))
463 G_LOCK (main_context_list);
464 main_context_list = g_slist_remove (main_context_list, context);
465 G_UNLOCK (main_context_list);
467 source = context->source_list;
470 GSource *next = source->next;
471 g_source_destroy_internal (source, context, FALSE);
475 #ifdef G_THREADS_ENABLED
476 g_static_mutex_free (&context->mutex);
479 g_ptr_array_free (context->pending_dispatches, TRUE);
480 g_free (context->cached_poll_array);
482 poll_rec_list_free (context, context->poll_records);
484 #ifdef G_THREADS_ENABLED
485 if (g_thread_supported())
488 close (context->wake_up_pipe[0]);
489 close (context->wake_up_pipe[1]);
491 CloseHandle (context->wake_up_semaphore);
495 main_contexts_without_pipe = g_slist_remove (main_contexts_without_pipe,
498 if (context->cond != NULL)
499 g_cond_free (context->cond);
505 #ifdef G_THREADS_ENABLED
507 g_main_context_init_pipe (GMainContext *context)
510 if (context->wake_up_pipe[0] != -1)
514 /* if this fails, we fall through and try pipe */
515 pipe2 (context->wake_up_pipe, O_CLOEXEC);
517 if (context->wake_up_pipe[0] == -1)
519 if (pipe (context->wake_up_pipe) < 0)
520 g_error ("Cannot create pipe main loop wake-up: %s\n",
523 fcntl (context->wake_up_pipe[0], F_SETFD, FD_CLOEXEC);
524 fcntl (context->wake_up_pipe[1], F_SETFD, FD_CLOEXEC);
527 context->wake_up_rec.fd = context->wake_up_pipe[0];
528 context->wake_up_rec.events = G_IO_IN;
530 if (context->wake_up_semaphore != NULL)
532 context->wake_up_semaphore = CreateSemaphore (NULL, 0, 100, NULL);
533 if (context->wake_up_semaphore == NULL)
534 g_error ("Cannot create wake-up semaphore: %s",
535 g_win32_error_message (GetLastError ()));
536 context->wake_up_rec.fd = (gintptr) context->wake_up_semaphore;
537 context->wake_up_rec.events = G_IO_IN;
539 if (_g_main_poll_debug)
540 g_print ("wake-up semaphore: %p\n", context->wake_up_semaphore);
542 g_main_context_add_poll_unlocked (context, 0, &context->wake_up_rec);
546 _g_main_thread_init (void)
548 GSList *curr = main_contexts_without_pipe;
551 g_main_context_init_pipe ((GMainContext *)curr->data);
554 g_slist_free (main_contexts_without_pipe);
555 main_contexts_without_pipe = NULL;
557 #endif /* G_THREADS_ENABLED */
560 * g_main_context_new:
562 * Creates a new #GMainContext structure.
564 * Return value: the new #GMainContext
567 g_main_context_new (void)
569 GMainContext *context = g_new0 (GMainContext, 1);
571 #ifdef G_MAIN_POLL_DEBUG
573 static gboolean beenhere = FALSE;
577 if (getenv ("G_MAIN_POLL_DEBUG") != NULL)
578 _g_main_poll_debug = TRUE;
584 #ifdef G_THREADS_ENABLED
585 g_static_mutex_init (&context->mutex);
587 context->owner = NULL;
588 context->waiters = NULL;
591 context->wake_up_pipe[0] = -1;
592 context->wake_up_pipe[1] = -1;
594 context->wake_up_semaphore = NULL;
598 context->ref_count = 1;
600 context->next_id = 1;
602 context->source_list = NULL;
604 context->poll_func = g_poll;
606 context->cached_poll_array = NULL;
607 context->cached_poll_array_size = 0;
609 context->pending_dispatches = g_ptr_array_new ();
611 context->time_is_fresh = FALSE;
612 context->current_time_is_fresh = FALSE;
614 #ifdef G_THREADS_ENABLED
615 if (g_thread_supported ())
616 g_main_context_init_pipe (context);
618 main_contexts_without_pipe = g_slist_prepend (main_contexts_without_pipe,
622 G_LOCK (main_context_list);
623 main_context_list = g_slist_append (main_context_list, context);
625 #ifdef G_MAIN_POLL_DEBUG
626 if (_g_main_poll_debug)
627 g_print ("created context=%p\n", context);
630 G_UNLOCK (main_context_list);
636 * g_main_context_default:
638 * Returns the global default main context. This is the main context
639 * used for main loop functions when a main loop is not explicitly
640 * specified, and corresponds to the "main" main loop. See also
641 * g_main_context_get_thread_default().
643 * Return value: the global default main context.
646 g_main_context_default (void)
652 if (!default_main_context)
654 default_main_context = g_main_context_new ();
655 #ifdef G_MAIN_POLL_DEBUG
656 if (_g_main_poll_debug)
657 g_print ("default context=%p\n", default_main_context);
661 G_UNLOCK (main_loop);
663 return default_main_context;
666 static GStaticPrivate thread_context_stack = G_STATIC_PRIVATE_INIT;
669 free_context_stack (gpointer data)
671 GQueue *stack = data;
672 GMainContext *context;
674 while (!g_queue_is_empty (stack))
676 context = g_queue_pop_head (stack);
677 g_main_context_release (context);
679 g_main_context_unref (context);
681 g_queue_free (stack);
685 * g_main_context_push_thread_default:
686 * @context: a #GMainContext, or %NULL for the global default context
688 * Acquires @context and sets it as the thread-default context for the
689 * current thread. This will cause certain asynchronous operations
690 * (such as most <link linkend="gio">gio</link>-based I/O) which are
691 * started in this thread to run under @context and deliver their
692 * results to its main loop, rather than running under the global
693 * default context in the main thread. Note that calling this function
694 * changes the context returned by
695 * g_main_context_get_thread_default(), <emphasis>not</emphasis> the
696 * one returned by g_main_context_default(), so it does not affect the
697 * context used by functions like g_idle_add().
699 * Normally you would call this function shortly after creating a new
700 * thread, passing it a #GMainContext which will be run by a
701 * #GMainLoop in that thread, to set a new default context for all
702 * async operations in that thread. (In this case, you don't need to
703 * ever call g_main_context_pop_thread_default().) In some cases
704 * however, you may want to schedule a single operation in a
705 * non-default context, or temporarily use a non-default context in
706 * the main thread. In that case, you can wrap the call to the
707 * asynchronous operation inside a
708 * g_main_context_push_thread_default() /
709 * g_main_context_pop_thread_default() pair, but it is up to you to
710 * ensure that no other asynchronous operations accidentally get
711 * started while the non-default context is active.
713 * Beware that libraries that predate this function may not correctly
714 * handle being used from a thread with a thread-default context. Eg,
715 * see g_file_supports_thread_contexts().
720 g_main_context_push_thread_default (GMainContext *context)
723 gboolean acquired_context;
725 acquired_context = g_main_context_acquire (context);
726 g_return_if_fail (acquired_context);
728 if (context == g_main_context_default ())
731 g_main_context_ref (context);
733 stack = g_static_private_get (&thread_context_stack);
736 stack = g_queue_new ();
737 g_static_private_set (&thread_context_stack, stack,
741 g_queue_push_head (stack, context);
745 * g_main_context_pop_thread_default:
746 * @context: a #GMainContext object, or %NULL
748 * Pops @context off the thread-default context stack (verifying that
749 * it was on the top of the stack).
754 g_main_context_pop_thread_default (GMainContext *context)
758 if (context == g_main_context_default ())
761 stack = g_static_private_get (&thread_context_stack);
763 g_return_if_fail (stack != NULL);
764 g_return_if_fail (g_queue_peek_head (stack) == context);
766 g_queue_pop_head (stack);
768 g_main_context_release (context);
770 g_main_context_unref (context);
774 * g_main_context_get_thread_default:
776 * Gets the thread-default #GMainContext for this thread. Asynchronous
777 * operations that want to be able to be run in contexts other than
778 * the default one should call this method to get a #GMainContext to
779 * add their #GSource<!-- -->s to. (Note that even in single-threaded
780 * programs applications may sometimes want to temporarily push a
781 * non-default context, so it is not safe to assume that this will
782 * always return %NULL if threads are not initialized.)
784 * Returns: the thread-default #GMainContext, or %NULL if the
785 * thread-default context is the global default context.
790 g_main_context_get_thread_default (void)
794 stack = g_static_private_get (&thread_context_stack);
796 return g_queue_peek_head (stack);
801 /* Hooks for adding to the main loop */
805 * @source_funcs: structure containing functions that implement
806 * the sources behavior.
807 * @struct_size: size of the #GSource structure to create.
809 * Creates a new #GSource structure. The size is specified to
810 * allow creating structures derived from #GSource that contain
811 * additional data. The size passed in must be at least
812 * <literal>sizeof (GSource)</literal>.
814 * The source will not initially be associated with any #GMainContext
815 * and must be added to one with g_source_attach() before it will be
818 * Return value: the newly-created #GSource.
821 g_source_new (GSourceFuncs *source_funcs,
826 g_return_val_if_fail (source_funcs != NULL, NULL);
827 g_return_val_if_fail (struct_size >= sizeof (GSource), NULL);
829 source = (GSource*) g_malloc0 (struct_size);
831 source->source_funcs = source_funcs;
832 source->ref_count = 1;
834 source->priority = G_PRIORITY_DEFAULT;
836 source->flags = G_HOOK_FLAG_ACTIVE;
838 /* NULL/0 initialization for all other fields */
843 /* Holds context's lock
846 g_source_list_add (GSource *source,
847 GMainContext *context)
849 GSource *tmp_source, *last_source;
852 tmp_source = context->source_list;
853 while (tmp_source && tmp_source->priority <= source->priority)
855 last_source = tmp_source;
856 tmp_source = tmp_source->next;
859 source->next = tmp_source;
861 tmp_source->prev = source;
863 source->prev = last_source;
865 last_source->next = source;
867 context->source_list = source;
870 /* Holds context's lock
873 g_source_list_remove (GSource *source,
874 GMainContext *context)
877 source->prev->next = source->next;
879 context->source_list = source->next;
882 source->next->prev = source->prev;
890 * @source: a #GSource
891 * @context: a #GMainContext (if %NULL, the default context will be used)
893 * Adds a #GSource to a @context so that it will be executed within
894 * that context. Remove it by calling g_source_destroy().
896 * Return value: the ID (greater than 0) for the source within the
900 g_source_attach (GSource *source,
901 GMainContext *context)
906 g_return_val_if_fail (source->context == NULL, 0);
907 g_return_val_if_fail (!SOURCE_DESTROYED (source), 0);
910 context = g_main_context_default ();
912 LOCK_CONTEXT (context);
914 source->context = context;
915 result = source->source_id = context->next_id++;
918 g_source_list_add (source, context);
920 tmp_list = source->poll_fds;
923 g_main_context_add_poll_unlocked (context, source->priority, tmp_list->data);
924 tmp_list = tmp_list->next;
927 #ifdef G_THREADS_ENABLED
928 /* Now wake up the main loop if it is waiting in the poll() */
929 g_main_context_wakeup_unlocked (context);
932 UNLOCK_CONTEXT (context);
938 g_source_destroy_internal (GSource *source,
939 GMainContext *context,
943 LOCK_CONTEXT (context);
945 if (!SOURCE_DESTROYED (source))
948 gpointer old_cb_data;
949 GSourceCallbackFuncs *old_cb_funcs;
951 source->flags &= ~G_HOOK_FLAG_ACTIVE;
953 old_cb_data = source->callback_data;
954 old_cb_funcs = source->callback_funcs;
956 source->callback_data = NULL;
957 source->callback_funcs = NULL;
961 UNLOCK_CONTEXT (context);
962 old_cb_funcs->unref (old_cb_data);
963 LOCK_CONTEXT (context);
966 if (!SOURCE_BLOCKED (source))
968 tmp_list = source->poll_fds;
971 g_main_context_remove_poll_unlocked (context, tmp_list->data);
972 tmp_list = tmp_list->next;
976 g_source_unref_internal (source, context, TRUE);
980 UNLOCK_CONTEXT (context);
985 * @source: a #GSource
987 * Removes a source from its #GMainContext, if any, and mark it as
988 * destroyed. The source cannot be subsequently added to another
992 g_source_destroy (GSource *source)
994 GMainContext *context;
996 g_return_if_fail (source != NULL);
998 context = source->context;
1001 g_source_destroy_internal (source, context, FALSE);
1003 source->flags &= ~G_HOOK_FLAG_ACTIVE;
1008 * @source: a #GSource
1010 * Returns the numeric ID for a particular source. The ID of a source
1011 * is a positive integer which is unique within a particular main loop
1012 * context. The reverse
1013 * mapping from ID to source is done by g_main_context_find_source_by_id().
1015 * Return value: the ID (greater than 0) for the source
1018 g_source_get_id (GSource *source)
1022 g_return_val_if_fail (source != NULL, 0);
1023 g_return_val_if_fail (source->context != NULL, 0);
1025 LOCK_CONTEXT (source->context);
1026 result = source->source_id;
1027 UNLOCK_CONTEXT (source->context);
1033 * g_source_get_context:
1034 * @source: a #GSource
1036 * Gets the #GMainContext with which the source is associated.
1037 * Calling this function on a destroyed source is an error.
1039 * Return value: the #GMainContext with which the source is associated,
1040 * or %NULL if the context has not yet been added
1044 g_source_get_context (GSource *source)
1046 g_return_val_if_fail (!SOURCE_DESTROYED (source), NULL);
1048 return source->context;
1052 * g_source_add_poll:
1053 * @source:a #GSource
1054 * @fd: a #GPollFD structure holding information about a file
1055 * descriptor to watch.
1057 * Adds a file descriptor to the set of file descriptors polled for
1058 * this source. This is usually combined with g_source_new() to add an
1059 * event source. The event source's check function will typically test
1060 * the @revents field in the #GPollFD struct and return %TRUE if events need
1064 g_source_add_poll (GSource *source,
1067 GMainContext *context;
1069 g_return_if_fail (source != NULL);
1070 g_return_if_fail (fd != NULL);
1071 g_return_if_fail (!SOURCE_DESTROYED (source));
1073 context = source->context;
1076 LOCK_CONTEXT (context);
1078 source->poll_fds = g_slist_prepend (source->poll_fds, fd);
1082 if (!SOURCE_BLOCKED (source))
1083 g_main_context_add_poll_unlocked (context, source->priority, fd);
1084 UNLOCK_CONTEXT (context);
1089 * g_source_remove_poll:
1090 * @source:a #GSource
1091 * @fd: a #GPollFD structure previously passed to g_source_add_poll().
1093 * Removes a file descriptor from the set of file descriptors polled for
1097 g_source_remove_poll (GSource *source,
1100 GMainContext *context;
1102 g_return_if_fail (source != NULL);
1103 g_return_if_fail (fd != NULL);
1104 g_return_if_fail (!SOURCE_DESTROYED (source));
1106 context = source->context;
1109 LOCK_CONTEXT (context);
1111 source->poll_fds = g_slist_remove (source->poll_fds, fd);
1115 if (!SOURCE_BLOCKED (source))
1116 g_main_context_remove_poll_unlocked (context, fd);
1117 UNLOCK_CONTEXT (context);
1122 * g_source_set_callback_indirect:
1123 * @source: the source
1124 * @callback_data: pointer to callback data "object"
1125 * @callback_funcs: functions for reference counting @callback_data
1126 * and getting the callback and data
1128 * Sets the callback function storing the data as a refcounted callback
1129 * "object". This is used internally. Note that calling
1130 * g_source_set_callback_indirect() assumes
1131 * an initial reference count on @callback_data, and thus
1132 * @callback_funcs->unref will eventually be called once more
1133 * than @callback_funcs->ref.
1136 g_source_set_callback_indirect (GSource *source,
1137 gpointer callback_data,
1138 GSourceCallbackFuncs *callback_funcs)
1140 GMainContext *context;
1141 gpointer old_cb_data;
1142 GSourceCallbackFuncs *old_cb_funcs;
1144 g_return_if_fail (source != NULL);
1145 g_return_if_fail (callback_funcs != NULL || callback_data == NULL);
1147 context = source->context;
1150 LOCK_CONTEXT (context);
1152 old_cb_data = source->callback_data;
1153 old_cb_funcs = source->callback_funcs;
1155 source->callback_data = callback_data;
1156 source->callback_funcs = callback_funcs;
1159 UNLOCK_CONTEXT (context);
1162 old_cb_funcs->unref (old_cb_data);
1166 g_source_callback_ref (gpointer cb_data)
1168 GSourceCallback *callback = cb_data;
1170 callback->ref_count++;
1175 g_source_callback_unref (gpointer cb_data)
1177 GSourceCallback *callback = cb_data;
1179 callback->ref_count--;
1180 if (callback->ref_count == 0)
1182 if (callback->notify)
1183 callback->notify (callback->data);
1189 g_source_callback_get (gpointer cb_data,
1194 GSourceCallback *callback = cb_data;
1196 *func = callback->func;
1197 *data = callback->data;
1200 static GSourceCallbackFuncs g_source_callback_funcs = {
1201 g_source_callback_ref,
1202 g_source_callback_unref,
1203 g_source_callback_get,
1207 * g_source_set_callback:
1208 * @source: the source
1209 * @func: a callback function
1210 * @data: the data to pass to callback function
1211 * @notify: a function to call when @data is no longer in use, or %NULL.
1213 * Sets the callback function for a source. The callback for a source is
1214 * called from the source's dispatch function.
1216 * The exact type of @func depends on the type of source; ie. you
1217 * should not count on @func being called with @data as its first
1220 * Typically, you won't use this function. Instead use functions specific
1221 * to the type of source you are using.
1224 g_source_set_callback (GSource *source,
1227 GDestroyNotify notify)
1229 GSourceCallback *new_callback;
1231 g_return_if_fail (source != NULL);
1233 new_callback = g_new (GSourceCallback, 1);
1235 new_callback->ref_count = 1;
1236 new_callback->func = func;
1237 new_callback->data = data;
1238 new_callback->notify = notify;
1240 g_source_set_callback_indirect (source, new_callback, &g_source_callback_funcs);
1245 * g_source_set_funcs:
1246 * @source: a #GSource
1247 * @funcs: the new #GSourceFuncs
1249 * Sets the source functions (can be used to override
1250 * default implementations) of an unattached source.
1255 g_source_set_funcs (GSource *source,
1256 GSourceFuncs *funcs)
1258 g_return_if_fail (source != NULL);
1259 g_return_if_fail (source->context == NULL);
1260 g_return_if_fail (source->ref_count > 0);
1261 g_return_if_fail (funcs != NULL);
1263 source->source_funcs = funcs;
1267 * g_source_set_priority:
1268 * @source: a #GSource
1269 * @priority: the new priority.
1271 * Sets the priority of a source. While the main loop is being
1272 * run, a source will be dispatched if it is ready to be dispatched and no sources
1273 * at a higher (numerically smaller) priority are ready to be dispatched.
1276 g_source_set_priority (GSource *source,
1280 GMainContext *context;
1282 g_return_if_fail (source != NULL);
1284 context = source->context;
1287 LOCK_CONTEXT (context);
1289 source->priority = priority;
1293 /* Remove the source from the context's source and then
1294 * add it back so it is sorted in the correct plcae
1296 g_source_list_remove (source, source->context);
1297 g_source_list_add (source, source->context);
1299 if (!SOURCE_BLOCKED (source))
1301 tmp_list = source->poll_fds;
1304 g_main_context_remove_poll_unlocked (context, tmp_list->data);
1305 g_main_context_add_poll_unlocked (context, priority, tmp_list->data);
1307 tmp_list = tmp_list->next;
1311 UNLOCK_CONTEXT (source->context);
1316 * g_source_get_priority:
1317 * @source: a #GSource
1319 * Gets the priority of a source.
1321 * Return value: the priority of the source
1324 g_source_get_priority (GSource *source)
1326 g_return_val_if_fail (source != NULL, 0);
1328 return source->priority;
1332 * g_source_set_can_recurse:
1333 * @source: a #GSource
1334 * @can_recurse: whether recursion is allowed for this source
1336 * Sets whether a source can be called recursively. If @can_recurse is
1337 * %TRUE, then while the source is being dispatched then this source
1338 * will be processed normally. Otherwise, all processing of this
1339 * source is blocked until the dispatch function returns.
1342 g_source_set_can_recurse (GSource *source,
1343 gboolean can_recurse)
1345 GMainContext *context;
1347 g_return_if_fail (source != NULL);
1349 context = source->context;
1352 LOCK_CONTEXT (context);
1355 source->flags |= G_SOURCE_CAN_RECURSE;
1357 source->flags &= ~G_SOURCE_CAN_RECURSE;
1360 UNLOCK_CONTEXT (context);
1364 * g_source_get_can_recurse:
1365 * @source: a #GSource
1367 * Checks whether a source is allowed to be called recursively.
1368 * see g_source_set_can_recurse().
1370 * Return value: whether recursion is allowed.
1373 g_source_get_can_recurse (GSource *source)
1375 g_return_val_if_fail (source != NULL, FALSE);
1377 return (source->flags & G_SOURCE_CAN_RECURSE) != 0;
1382 * g_source_set_name:
1383 * @source: a #GSource
1384 * @name: debug name for the source
1386 * Sets a name for the source, used in debugging and profiling.
1387 * The name defaults to #NULL.
1389 * The source name should describe in a human-readable way
1390 * what the source does. For example, "X11 event queue"
1391 * or "GTK+ repaint idle handler" or whatever it is.
1393 * It is permitted to call this function multiple times, but is not
1394 * recommended due to the potential performance impact. For example,
1395 * one could change the name in the "check" function of a #GSourceFuncs
1396 * to include details like the event type in the source name.
1401 g_source_set_name (GSource *source,
1404 g_return_if_fail (source != NULL);
1406 /* setting back to NULL is allowed, just because it's
1407 * weird if get_name can return NULL but you can't
1411 g_free (source->name);
1412 source->name = g_strdup (name);
1416 * g_source_get_name:
1417 * @source: a #GSource
1419 * Gets a name for the source, used in debugging and profiling.
1420 * The name may be #NULL if it has never been set with
1421 * g_source_set_name().
1423 * Return value: the name of the source
1426 G_CONST_RETURN char*
1427 g_source_get_name (GSource *source)
1429 g_return_val_if_fail (source != NULL, NULL);
1431 return source->name;
1435 * g_source_set_name_by_id:
1436 * @tag: a #GSource ID
1437 * @name: debug name for the source
1439 * Sets the name of a source using its ID.
1441 * This is a convenience utility to set source names from the return
1442 * value of g_idle_add(), g_timeout_add(), etc.
1447 g_source_set_name_by_id (guint tag,
1452 g_return_if_fail (tag > 0);
1454 source = g_main_context_find_source_by_id (NULL, tag);
1458 g_source_set_name (source, name);
1464 * @source: a #GSource
1466 * Increases the reference count on a source by one.
1468 * Return value: @source
1471 g_source_ref (GSource *source)
1473 GMainContext *context;
1475 g_return_val_if_fail (source != NULL, NULL);
1477 context = source->context;
1480 LOCK_CONTEXT (context);
1482 source->ref_count++;
1485 UNLOCK_CONTEXT (context);
1490 /* g_source_unref() but possible to call within context lock
1493 g_source_unref_internal (GSource *source,
1494 GMainContext *context,
1497 gpointer old_cb_data = NULL;
1498 GSourceCallbackFuncs *old_cb_funcs = NULL;
1500 g_return_if_fail (source != NULL);
1502 if (!have_lock && context)
1503 LOCK_CONTEXT (context);
1505 source->ref_count--;
1506 if (source->ref_count == 0)
1508 old_cb_data = source->callback_data;
1509 old_cb_funcs = source->callback_funcs;
1511 source->callback_data = NULL;
1512 source->callback_funcs = NULL;
1514 if (context && !SOURCE_DESTROYED (source))
1516 g_warning (G_STRLOC ": ref_count == 0, but source is still attached to a context!");
1517 source->ref_count++;
1520 g_source_list_remove (source, context);
1522 if (source->source_funcs->finalize)
1523 source->source_funcs->finalize (source);
1525 g_free (source->name);
1526 source->name = NULL;
1528 g_slist_free (source->poll_fds);
1529 source->poll_fds = NULL;
1533 if (!have_lock && context)
1534 UNLOCK_CONTEXT (context);
1539 UNLOCK_CONTEXT (context);
1541 old_cb_funcs->unref (old_cb_data);
1544 LOCK_CONTEXT (context);
1550 * @source: a #GSource
1552 * Decreases the reference count of a source by one. If the
1553 * resulting reference count is zero the source and associated
1554 * memory will be destroyed.
1557 g_source_unref (GSource *source)
1559 g_return_if_fail (source != NULL);
1561 g_source_unref_internal (source, source->context, FALSE);
1565 * g_main_context_find_source_by_id:
1566 * @context: a #GMainContext (if %NULL, the default context will be used)
1567 * @source_id: the source ID, as returned by g_source_get_id().
1569 * Finds a #GSource given a pair of context and ID.
1571 * Return value: the #GSource if found, otherwise, %NULL
1574 g_main_context_find_source_by_id (GMainContext *context,
1579 g_return_val_if_fail (source_id > 0, NULL);
1581 if (context == NULL)
1582 context = g_main_context_default ();
1584 LOCK_CONTEXT (context);
1586 source = context->source_list;
1589 if (!SOURCE_DESTROYED (source) &&
1590 source->source_id == source_id)
1592 source = source->next;
1595 UNLOCK_CONTEXT (context);
1601 * g_main_context_find_source_by_funcs_user_data:
1602 * @context: a #GMainContext (if %NULL, the default context will be used).
1603 * @funcs: the @source_funcs passed to g_source_new().
1604 * @user_data: the user data from the callback.
1606 * Finds a source with the given source functions and user data. If
1607 * multiple sources exist with the same source function and user data,
1608 * the first one found will be returned.
1610 * Return value: the source, if one was found, otherwise %NULL
1613 g_main_context_find_source_by_funcs_user_data (GMainContext *context,
1614 GSourceFuncs *funcs,
1619 g_return_val_if_fail (funcs != NULL, NULL);
1621 if (context == NULL)
1622 context = g_main_context_default ();
1624 LOCK_CONTEXT (context);
1626 source = context->source_list;
1629 if (!SOURCE_DESTROYED (source) &&
1630 source->source_funcs == funcs &&
1631 source->callback_funcs)
1633 GSourceFunc callback;
1634 gpointer callback_data;
1636 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
1638 if (callback_data == user_data)
1641 source = source->next;
1644 UNLOCK_CONTEXT (context);
1650 * g_main_context_find_source_by_user_data:
1651 * @context: a #GMainContext
1652 * @user_data: the user_data for the callback.
1654 * Finds a source with the given user data for the callback. If
1655 * multiple sources exist with the same user data, the first
1656 * one found will be returned.
1658 * Return value: the source, if one was found, otherwise %NULL
1661 g_main_context_find_source_by_user_data (GMainContext *context,
1666 if (context == NULL)
1667 context = g_main_context_default ();
1669 LOCK_CONTEXT (context);
1671 source = context->source_list;
1674 if (!SOURCE_DESTROYED (source) &&
1675 source->callback_funcs)
1677 GSourceFunc callback;
1678 gpointer callback_data = NULL;
1680 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
1682 if (callback_data == user_data)
1685 source = source->next;
1688 UNLOCK_CONTEXT (context);
1695 * @tag: the ID of the source to remove.
1697 * Removes the source with the given id from the default main context.
1699 * a #GSource is given by g_source_get_id(), or will be returned by the
1700 * functions g_source_attach(), g_idle_add(), g_idle_add_full(),
1701 * g_timeout_add(), g_timeout_add_full(), g_child_watch_add(),
1702 * g_child_watch_add_full(), g_io_add_watch(), and g_io_add_watch_full().
1704 * See also g_source_destroy(). You must use g_source_destroy() for sources
1705 * added to a non-default main context.
1707 * Return value: %TRUE if the source was found and removed.
1710 g_source_remove (guint tag)
1714 g_return_val_if_fail (tag > 0, FALSE);
1716 source = g_main_context_find_source_by_id (NULL, tag);
1718 g_source_destroy (source);
1720 return source != NULL;
1724 * g_source_remove_by_user_data:
1725 * @user_data: the user_data for the callback.
1727 * Removes a source from the default main loop context given the user
1728 * data for the callback. If multiple sources exist with the same user
1729 * data, only one will be destroyed.
1731 * Return value: %TRUE if a source was found and removed.
1734 g_source_remove_by_user_data (gpointer user_data)
1738 source = g_main_context_find_source_by_user_data (NULL, user_data);
1741 g_source_destroy (source);
1749 * g_source_remove_by_funcs_user_data:
1750 * @funcs: The @source_funcs passed to g_source_new()
1751 * @user_data: the user data for the callback
1753 * Removes a source from the default main loop context given the
1754 * source functions and user data. If multiple sources exist with the
1755 * same source functions and user data, only one will be destroyed.
1757 * Return value: %TRUE if a source was found and removed.
1760 g_source_remove_by_funcs_user_data (GSourceFuncs *funcs,
1765 g_return_val_if_fail (funcs != NULL, FALSE);
1767 source = g_main_context_find_source_by_funcs_user_data (NULL, funcs, user_data);
1770 g_source_destroy (source);
1778 * g_get_current_time:
1779 * @result: #GTimeVal structure in which to store current time.
1781 * Equivalent to the UNIX gettimeofday() function, but portable.
1784 g_get_current_time (GTimeVal *result)
1789 g_return_if_fail (result != NULL);
1791 /*this is required on alpha, there the timeval structs are int's
1792 not longs and a cast only would fail horribly*/
1793 gettimeofday (&r, NULL);
1794 result->tv_sec = r.tv_sec;
1795 result->tv_usec = r.tv_usec;
1800 g_return_if_fail (result != NULL);
1802 GetSystemTimeAsFileTime (&ft);
1803 memmove (&time64, &ft, sizeof (FILETIME));
1805 /* Convert from 100s of nanoseconds since 1601-01-01
1806 * to Unix epoch. Yes, this is Y2038 unsafe.
1808 time64 -= G_GINT64_CONSTANT (116444736000000000);
1811 result->tv_sec = time64 / 1000000;
1812 result->tv_usec = time64 % 1000000;
1819 * Represents a precise time, with seconds and nanoseconds. This is
1820 * similar to POSIX <structname>struct timespec</structname>. This
1821 * structure can be filled in with g_get_monotonic_time().
1827 * g_get_monotonic_time:
1829 * Queries the system monotonic time, if available.
1831 * On POSIX systems with clock_gettime() and %CLOCK_MONOTONIC this call
1832 * is a very shallow wrapper for that. Otherwise, we make a best effort
1833 * that probably involves returning the wall clock time (with at least
1834 * microsecond accuracy, subject to the limitations of the OS kernel).
1836 * Note that, on Windows, "limitations of the OS kernel" is a rather
1837 * substantial statement. Depending on the configuration of the system,
1838 * the wall clock time is updated as infrequently as 64 times a second
1839 * (which is approximately every 16ms).
1841 * Returns: the monotonic time, in microseconds
1846 g_get_monotonic_time (void)
1848 #ifdef HAVE_CLOCK_GETTIME
1849 /* librt clock_gettime() is our first choice */
1851 static int clockid = CLOCK_REALTIME;
1854 #ifdef HAVE_MONOTONIC_CLOCK
1855 /* We have to check if we actually have monotonic clock support.
1857 * There is no thread safety issue here since there is no harm if we
1861 static gboolean checked;
1863 if G_UNLIKELY (!checked)
1865 if (sysconf (_SC_MONOTONIC_CLOCK) >= 0)
1866 clockid = CLOCK_MONOTONIC;
1872 clock_gettime (clockid, &ts);
1874 /* In theory monotonic time can have any epoch.
1876 * glib presently assumes the following:
1878 * 1) The epoch comes some time after the birth of Jesus of Nazareth, but
1879 * not more than 10000 years later.
1881 * 2) The current time also falls sometime within this range.
1883 * These two reasonable assumptions leave us with a maximum deviation from
1884 * the epoch of 10000 years, or 315569520000000000 seconds.
1886 * If we restrict ourselves to this range then the number of microseconds
1887 * will always fit well inside the constraints of a int64 (by a factor of
1890 * If you actually hit the following assertion, probably you should file a
1891 * bug against your operating system for being excessively silly.
1893 g_assert (G_GINT64_CONSTANT (-315569520000000000) < ts.tv_sec &&
1894 ts.tv_sec < G_GINT64_CONSTANT (315569520000000000));
1896 return (((gint64) ts.tv_sec) * 1000000) + (ts.tv_nsec / 1000);
1899 /* It may look like we are discarding accuracy on Windows (since its
1900 * current time is expressed in 100s of nanoseconds) but according to
1901 * many sources, the time is only updated 64 times per second, so
1902 * microsecond accuracy is more than enough.
1907 g_get_current_time (&tv);
1909 return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec;
1915 g_main_dispatch_free (gpointer dispatch)
1917 g_slice_free (GMainDispatch, dispatch);
1920 /* Running the main loop */
1922 static GMainDispatch *
1925 static GStaticPrivate depth_private = G_STATIC_PRIVATE_INIT;
1926 GMainDispatch *dispatch = g_static_private_get (&depth_private);
1929 dispatch = g_slice_new0 (GMainDispatch);
1930 g_static_private_set (&depth_private, dispatch, g_main_dispatch_free);
1939 * Returns the depth of the stack of calls to
1940 * g_main_context_dispatch() on any #GMainContext in the current thread.
1941 * That is, when called from the toplevel, it gives 0. When
1942 * called from within a callback from g_main_context_iteration()
1943 * (or g_main_loop_run(), etc.) it returns 1. When called from within
1944 * a callback to a recursive call to g_main_context_iterate(),
1945 * it returns 2. And so forth.
1947 * This function is useful in a situation like the following:
1948 * Imagine an extremely simple "garbage collected" system.
1951 * static GList *free_list;
1954 * allocate_memory (gsize size)
1956 * gpointer result = g_malloc (size);
1957 * free_list = g_list_prepend (free_list, result);
1962 * free_allocated_memory (void)
1965 * for (l = free_list; l; l = l->next);
1967 * g_list_free (free_list);
1975 * g_main_context_iteration (NULL, TRUE);
1976 * free_allocated_memory();
1980 * This works from an application, however, if you want to do the same
1981 * thing from a library, it gets more difficult, since you no longer
1982 * control the main loop. You might think you can simply use an idle
1983 * function to make the call to free_allocated_memory(), but that
1984 * doesn't work, since the idle function could be called from a
1985 * recursive callback. This can be fixed by using g_main_depth()
1989 * allocate_memory (gsize size)
1991 * FreeListBlock *block = g_new (FreeListBlock, 1);
1992 * block->mem = g_malloc (size);
1993 * block->depth = g_main_depth ();
1994 * free_list = g_list_prepend (free_list, block);
1995 * return block->mem;
1999 * free_allocated_memory (void)
2003 * int depth = g_main_depth ();
2004 * for (l = free_list; l; );
2006 * GList *next = l->next;
2007 * FreeListBlock *block = l->data;
2008 * if (block->depth > depth)
2010 * g_free (block->mem);
2012 * free_list = g_list_delete_link (free_list, l);
2020 * There is a temptation to use g_main_depth() to solve
2021 * problems with reentrancy. For instance, while waiting for data
2022 * to be received from the network in response to a menu item,
2023 * the menu item might be selected again. It might seem that
2024 * one could make the menu item's callback return immediately
2025 * and do nothing if g_main_depth() returns a value greater than 1.
2026 * However, this should be avoided since the user then sees selecting
2027 * the menu item do nothing. Furthermore, you'll find yourself adding
2028 * these checks all over your code, since there are doubtless many,
2029 * many things that the user could do. Instead, you can use the
2030 * following techniques:
2035 * Use gtk_widget_set_sensitive() or modal dialogs to prevent
2036 * the user from interacting with elements while the main
2037 * loop is recursing.
2042 * Avoid main loop recursion in situations where you can't handle
2043 * arbitrary callbacks. Instead, structure your code so that you
2044 * simply return to the main loop and then get called again when
2045 * there is more work to do.
2050 * Return value: The main loop recursion level in the current thread
2055 GMainDispatch *dispatch = get_dispatch ();
2056 return dispatch->depth;
2060 * g_main_current_source:
2062 * Returns the currently firing source for this thread.
2064 * Return value: The currently firing source or %NULL.
2069 g_main_current_source (void)
2071 GMainDispatch *dispatch = get_dispatch ();
2072 return dispatch->dispatching_sources ? dispatch->dispatching_sources->data : NULL;
2076 * g_source_is_destroyed:
2077 * @source: a #GSource
2079 * Returns whether @source has been destroyed.
2081 * This is important when you operate upon your objects
2082 * from within idle handlers, but may have freed the object
2083 * before the dispatch of your idle handler.
2087 * idle_callback (gpointer data)
2089 * SomeWidget *self = data;
2091 * GDK_THREADS_ENTER (<!-- -->);
2092 * /<!-- -->* do stuff with self *<!-- -->/
2093 * self->idle_id = 0;
2094 * GDK_THREADS_LEAVE (<!-- -->);
2100 * some_widget_do_stuff_later (SomeWidget *self)
2102 * self->idle_id = g_idle_add (idle_callback, self);
2106 * some_widget_finalize (GObject *object)
2108 * SomeWidget *self = SOME_WIDGET (object);
2110 * if (self->idle_id)
2111 * g_source_remove (self->idle_id);
2113 * G_OBJECT_CLASS (parent_class)->finalize (object);
2117 * This will fail in a multi-threaded application if the
2118 * widget is destroyed before the idle handler fires due
2119 * to the use after free in the callback. A solution, to
2120 * this particular problem, is to check to if the source
2121 * has already been destroy within the callback.
2125 * idle_callback (gpointer data)
2127 * SomeWidget *self = data;
2129 * GDK_THREADS_ENTER ();
2130 * if (!g_source_is_destroyed (g_main_current_source ()))
2132 * /<!-- -->* do stuff with self *<!-- -->/
2134 * GDK_THREADS_LEAVE ();
2140 * Return value: %TRUE if the source has been destroyed
2145 g_source_is_destroyed (GSource *source)
2147 return SOURCE_DESTROYED (source);
2150 /* Temporarily remove all this source's file descriptors from the
2151 * poll(), so that if data comes available for one of the file descriptors
2152 * we don't continually spin in the poll()
2154 /* HOLDS: source->context's lock */
2156 block_source (GSource *source)
2160 g_return_if_fail (!SOURCE_BLOCKED (source));
2162 tmp_list = source->poll_fds;
2165 g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
2166 tmp_list = tmp_list->next;
2170 /* HOLDS: source->context's lock */
2172 unblock_source (GSource *source)
2176 g_return_if_fail (!SOURCE_BLOCKED (source)); /* Source already unblocked */
2177 g_return_if_fail (!SOURCE_DESTROYED (source));
2179 tmp_list = source->poll_fds;
2182 g_main_context_add_poll_unlocked (source->context, source->priority, tmp_list->data);
2183 tmp_list = tmp_list->next;
2187 /* HOLDS: context's lock */
2189 g_main_dispatch (GMainContext *context)
2191 GMainDispatch *current = get_dispatch ();
2194 for (i = 0; i < context->pending_dispatches->len; i++)
2196 GSource *source = context->pending_dispatches->pdata[i];
2198 context->pending_dispatches->pdata[i] = NULL;
2201 source->flags &= ~G_SOURCE_READY;
2203 if (!SOURCE_DESTROYED (source))
2205 gboolean was_in_call;
2206 gpointer user_data = NULL;
2207 GSourceFunc callback = NULL;
2208 GSourceCallbackFuncs *cb_funcs;
2210 gboolean need_destroy;
2212 gboolean (*dispatch) (GSource *,
2215 GSList current_source_link;
2217 dispatch = source->source_funcs->dispatch;
2218 cb_funcs = source->callback_funcs;
2219 cb_data = source->callback_data;
2222 cb_funcs->ref (cb_data);
2224 if ((source->flags & G_SOURCE_CAN_RECURSE) == 0)
2225 block_source (source);
2227 was_in_call = source->flags & G_HOOK_FLAG_IN_CALL;
2228 source->flags |= G_HOOK_FLAG_IN_CALL;
2231 cb_funcs->get (cb_data, source, &callback, &user_data);
2233 UNLOCK_CONTEXT (context);
2236 /* The on-stack allocation of the GSList is unconventional, but
2237 * we know that the lifetime of the link is bounded to this
2238 * function as the link is kept in a thread specific list and
2239 * not manipulated outside of this function and its descendants.
2240 * Avoiding the overhead of a g_slist_alloc() is useful as many
2241 * applications do little more than dispatch events.
2243 * This is a performance hack - do not revert to g_slist_prepend()!
2245 current_source_link.data = source;
2246 current_source_link.next = current->dispatching_sources;
2247 current->dispatching_sources = ¤t_source_link;
2248 need_destroy = ! dispatch (source,
2251 g_assert (current->dispatching_sources == ¤t_source_link);
2252 current->dispatching_sources = current_source_link.next;
2256 cb_funcs->unref (cb_data);
2258 LOCK_CONTEXT (context);
2261 source->flags &= ~G_HOOK_FLAG_IN_CALL;
2263 if ((source->flags & G_SOURCE_CAN_RECURSE) == 0 &&
2264 !SOURCE_DESTROYED (source))
2265 unblock_source (source);
2267 /* Note: this depends on the fact that we can't switch
2268 * sources from one main context to another
2270 if (need_destroy && !SOURCE_DESTROYED (source))
2272 g_assert (source->context == context);
2273 g_source_destroy_internal (source, context, TRUE);
2277 SOURCE_UNREF (source, context);
2280 g_ptr_array_set_size (context->pending_dispatches, 0);
2283 /* Holds context's lock */
2284 static inline GSource *
2285 next_valid_source (GMainContext *context,
2288 GSource *new_source = source ? source->next : context->source_list;
2292 if (!SOURCE_DESTROYED (new_source))
2294 new_source->ref_count++;
2298 new_source = new_source->next;
2302 SOURCE_UNREF (source, context);
2308 * g_main_context_acquire:
2309 * @context: a #GMainContext
2311 * Tries to become the owner of the specified context.
2312 * If some other thread is the owner of the context,
2313 * returns %FALSE immediately. Ownership is properly
2314 * recursive: the owner can require ownership again
2315 * and will release ownership when g_main_context_release()
2316 * is called as many times as g_main_context_acquire().
2318 * You must be the owner of a context before you
2319 * can call g_main_context_prepare(), g_main_context_query(),
2320 * g_main_context_check(), g_main_context_dispatch().
2322 * Return value: %TRUE if the operation succeeded, and
2323 * this thread is now the owner of @context.
2326 g_main_context_acquire (GMainContext *context)
2328 #ifdef G_THREADS_ENABLED
2329 gboolean result = FALSE;
2330 GThread *self = G_THREAD_SELF;
2332 if (context == NULL)
2333 context = g_main_context_default ();
2335 LOCK_CONTEXT (context);
2337 if (!context->owner)
2339 context->owner = self;
2340 g_assert (context->owner_count == 0);
2343 if (context->owner == self)
2345 context->owner_count++;
2349 UNLOCK_CONTEXT (context);
2352 #else /* !G_THREADS_ENABLED */
2354 #endif /* G_THREADS_ENABLED */
2358 * g_main_context_release:
2359 * @context: a #GMainContext
2361 * Releases ownership of a context previously acquired by this thread
2362 * with g_main_context_acquire(). If the context was acquired multiple
2363 * times, the ownership will be released only when g_main_context_release()
2364 * is called as many times as it was acquired.
2367 g_main_context_release (GMainContext *context)
2369 #ifdef G_THREADS_ENABLED
2370 if (context == NULL)
2371 context = g_main_context_default ();
2373 LOCK_CONTEXT (context);
2375 context->owner_count--;
2376 if (context->owner_count == 0)
2378 context->owner = NULL;
2380 if (context->waiters)
2382 GMainWaiter *waiter = context->waiters->data;
2383 gboolean loop_internal_waiter =
2384 (waiter->mutex == g_static_mutex_get_mutex (&context->mutex));
2385 context->waiters = g_slist_delete_link (context->waiters,
2387 if (!loop_internal_waiter)
2388 g_mutex_lock (waiter->mutex);
2390 g_cond_signal (waiter->cond);
2392 if (!loop_internal_waiter)
2393 g_mutex_unlock (waiter->mutex);
2397 UNLOCK_CONTEXT (context);
2398 #endif /* G_THREADS_ENABLED */
2402 * g_main_context_wait:
2403 * @context: a #GMainContext
2404 * @cond: a condition variable
2405 * @mutex: a mutex, currently held
2407 * Tries to become the owner of the specified context,
2408 * as with g_main_context_acquire(). But if another thread
2409 * is the owner, atomically drop @mutex and wait on @cond until
2410 * that owner releases ownership or until @cond is signaled, then
2411 * try again (once) to become the owner.
2413 * Return value: %TRUE if the operation succeeded, and
2414 * this thread is now the owner of @context.
2417 g_main_context_wait (GMainContext *context,
2421 #ifdef G_THREADS_ENABLED
2422 gboolean result = FALSE;
2423 GThread *self = G_THREAD_SELF;
2424 gboolean loop_internal_waiter;
2426 if (context == NULL)
2427 context = g_main_context_default ();
2429 loop_internal_waiter = (mutex == g_static_mutex_get_mutex (&context->mutex));
2431 if (!loop_internal_waiter)
2432 LOCK_CONTEXT (context);
2434 if (context->owner && context->owner != self)
2439 waiter.mutex = mutex;
2441 context->waiters = g_slist_append (context->waiters, &waiter);
2443 if (!loop_internal_waiter)
2444 UNLOCK_CONTEXT (context);
2445 g_cond_wait (cond, mutex);
2446 if (!loop_internal_waiter)
2447 LOCK_CONTEXT (context);
2449 context->waiters = g_slist_remove (context->waiters, &waiter);
2452 if (!context->owner)
2454 context->owner = self;
2455 g_assert (context->owner_count == 0);
2458 if (context->owner == self)
2460 context->owner_count++;
2464 if (!loop_internal_waiter)
2465 UNLOCK_CONTEXT (context);
2468 #else /* !G_THREADS_ENABLED */
2470 #endif /* G_THREADS_ENABLED */
2474 * g_main_context_prepare:
2475 * @context: a #GMainContext
2476 * @priority: location to store priority of highest priority
2477 * source already ready.
2479 * Prepares to poll sources within a main loop. The resulting information
2480 * for polling is determined by calling g_main_context_query ().
2482 * Return value: %TRUE if some source is ready to be dispatched
2486 g_main_context_prepare (GMainContext *context,
2491 gint current_priority = G_MAXINT;
2494 if (context == NULL)
2495 context = g_main_context_default ();
2497 LOCK_CONTEXT (context);
2499 context->time_is_fresh = FALSE;
2500 context->current_time_is_fresh = FALSE;
2502 if (context->in_check_or_prepare)
2504 g_warning ("g_main_context_prepare() called recursively from within a source's check() or "
2505 "prepare() member.");
2506 UNLOCK_CONTEXT (context);
2510 #ifdef G_THREADS_ENABLED
2511 if (context->poll_waiting)
2513 g_warning("g_main_context_prepare(): main loop already active in another thread");
2514 UNLOCK_CONTEXT (context);
2518 context->poll_waiting = TRUE;
2519 #endif /* G_THREADS_ENABLED */
2522 /* If recursing, finish up current dispatch, before starting over */
2523 if (context->pending_dispatches)
2526 g_main_dispatch (context, ¤t_time);
2528 UNLOCK_CONTEXT (context);
2533 /* If recursing, clear list of pending dispatches */
2535 for (i = 0; i < context->pending_dispatches->len; i++)
2537 if (context->pending_dispatches->pdata[i])
2538 SOURCE_UNREF ((GSource *)context->pending_dispatches->pdata[i], context);
2540 g_ptr_array_set_size (context->pending_dispatches, 0);
2542 /* Prepare all sources */
2544 context->timeout = -1;
2546 source = next_valid_source (context, NULL);
2549 gint source_timeout = -1;
2551 if ((n_ready > 0) && (source->priority > current_priority))
2553 SOURCE_UNREF (source, context);
2556 if (SOURCE_BLOCKED (source))
2559 if (!(source->flags & G_SOURCE_READY))
2562 gboolean (*prepare) (GSource *source,
2565 prepare = source->source_funcs->prepare;
2566 context->in_check_or_prepare++;
2567 UNLOCK_CONTEXT (context);
2569 result = (*prepare) (source, &source_timeout);
2571 LOCK_CONTEXT (context);
2572 context->in_check_or_prepare--;
2575 source->flags |= G_SOURCE_READY;
2578 if (source->flags & G_SOURCE_READY)
2581 current_priority = source->priority;
2582 context->timeout = 0;
2585 if (source_timeout >= 0)
2587 if (context->timeout < 0)
2588 context->timeout = source_timeout;
2590 context->timeout = MIN (context->timeout, source_timeout);
2594 source = next_valid_source (context, source);
2597 UNLOCK_CONTEXT (context);
2600 *priority = current_priority;
2602 return (n_ready > 0);
2606 * g_main_context_query:
2607 * @context: a #GMainContext
2608 * @max_priority: maximum priority source to check
2609 * @timeout_: location to store timeout to be used in polling
2610 * @fds: location to store #GPollFD records that need to be polled.
2611 * @n_fds: length of @fds.
2613 * Determines information necessary to poll this main loop.
2615 * Return value: the number of records actually stored in @fds,
2616 * or, if more than @n_fds records need to be stored, the number
2617 * of records that need to be stored.
2620 g_main_context_query (GMainContext *context,
2629 LOCK_CONTEXT (context);
2631 pollrec = context->poll_records;
2633 while (pollrec && max_priority >= pollrec->priority)
2635 /* We need to include entries with fd->events == 0 in the array because
2636 * otherwise if the application changes fd->events behind our back and
2637 * makes it non-zero, we'll be out of sync when we check the fds[] array.
2638 * (Changing fd->events after adding an FD wasn't an anticipated use of
2639 * this API, but it occurs in practice.) */
2642 fds[n_poll].fd = pollrec->fd->fd;
2643 /* In direct contradiction to the Unix98 spec, IRIX runs into
2644 * difficulty if you pass in POLLERR, POLLHUP or POLLNVAL
2645 * flags in the events field of the pollfd while it should
2646 * just ignoring them. So we mask them out here.
2648 fds[n_poll].events = pollrec->fd->events & ~(G_IO_ERR|G_IO_HUP|G_IO_NVAL);
2649 fds[n_poll].revents = 0;
2652 pollrec = pollrec->next;
2656 #ifdef G_THREADS_ENABLED
2657 context->poll_changed = FALSE;
2662 *timeout = context->timeout;
2665 context->time_is_fresh = FALSE;
2666 context->current_time_is_fresh = FALSE;
2670 UNLOCK_CONTEXT (context);
2676 * g_main_context_check:
2677 * @context: a #GMainContext
2678 * @max_priority: the maximum numerical priority of sources to check
2679 * @fds: array of #GPollFD's that was passed to the last call to
2680 * g_main_context_query()
2681 * @n_fds: return value of g_main_context_query()
2683 * Passes the results of polling back to the main loop.
2685 * Return value: %TRUE if some sources are ready to be dispatched.
2688 g_main_context_check (GMainContext *context,
2698 LOCK_CONTEXT (context);
2700 if (context->in_check_or_prepare)
2702 g_warning ("g_main_context_check() called recursively from within a source's check() or "
2703 "prepare() member.");
2704 UNLOCK_CONTEXT (context);
2708 #ifdef G_THREADS_ENABLED
2709 if (!context->poll_waiting)
2713 read (context->wake_up_pipe[0], &a, 1);
2717 context->poll_waiting = FALSE;
2719 /* If the set of poll file descriptors changed, bail out
2720 * and let the main loop rerun
2722 if (context->poll_changed)
2724 UNLOCK_CONTEXT (context);
2727 #endif /* G_THREADS_ENABLED */
2729 pollrec = context->poll_records;
2733 if (pollrec->fd->events)
2734 pollrec->fd->revents = fds[i].revents;
2736 pollrec = pollrec->next;
2740 source = next_valid_source (context, NULL);
2743 if ((n_ready > 0) && (source->priority > max_priority))
2745 SOURCE_UNREF (source, context);
2748 if (SOURCE_BLOCKED (source))
2751 if (!(source->flags & G_SOURCE_READY))
2754 gboolean (*check) (GSource *source);
2756 check = source->source_funcs->check;
2758 context->in_check_or_prepare++;
2759 UNLOCK_CONTEXT (context);
2761 result = (*check) (source);
2763 LOCK_CONTEXT (context);
2764 context->in_check_or_prepare--;
2767 source->flags |= G_SOURCE_READY;
2770 if (source->flags & G_SOURCE_READY)
2772 source->ref_count++;
2773 g_ptr_array_add (context->pending_dispatches, source);
2777 /* never dispatch sources with less priority than the first
2778 * one we choose to dispatch
2780 max_priority = source->priority;
2784 source = next_valid_source (context, source);
2787 UNLOCK_CONTEXT (context);
2793 * g_main_context_dispatch:
2794 * @context: a #GMainContext
2796 * Dispatches all pending sources.
2799 g_main_context_dispatch (GMainContext *context)
2801 LOCK_CONTEXT (context);
2803 if (context->pending_dispatches->len > 0)
2805 g_main_dispatch (context);
2808 UNLOCK_CONTEXT (context);
2811 /* HOLDS context lock */
2813 g_main_context_iterate (GMainContext *context,
2820 gboolean some_ready;
2821 gint nfds, allocated_nfds;
2822 GPollFD *fds = NULL;
2824 UNLOCK_CONTEXT (context);
2826 #ifdef G_THREADS_ENABLED
2827 if (!g_main_context_acquire (context))
2829 gboolean got_ownership;
2831 LOCK_CONTEXT (context);
2833 g_return_val_if_fail (g_thread_supported (), FALSE);
2839 context->cond = g_cond_new ();
2841 got_ownership = g_main_context_wait (context,
2843 g_static_mutex_get_mutex (&context->mutex));
2849 LOCK_CONTEXT (context);
2850 #endif /* G_THREADS_ENABLED */
2852 if (!context->cached_poll_array)
2854 context->cached_poll_array_size = context->n_poll_records;
2855 context->cached_poll_array = g_new (GPollFD, context->n_poll_records);
2858 allocated_nfds = context->cached_poll_array_size;
2859 fds = context->cached_poll_array;
2861 UNLOCK_CONTEXT (context);
2863 g_main_context_prepare (context, &max_priority);
2865 while ((nfds = g_main_context_query (context, max_priority, &timeout, fds,
2866 allocated_nfds)) > allocated_nfds)
2868 LOCK_CONTEXT (context);
2870 context->cached_poll_array_size = allocated_nfds = nfds;
2871 context->cached_poll_array = fds = g_new (GPollFD, nfds);
2872 UNLOCK_CONTEXT (context);
2878 g_main_context_poll (context, timeout, max_priority, fds, nfds);
2880 some_ready = g_main_context_check (context, max_priority, fds, nfds);
2883 g_main_context_dispatch (context);
2885 #ifdef G_THREADS_ENABLED
2886 g_main_context_release (context);
2887 #endif /* G_THREADS_ENABLED */
2889 LOCK_CONTEXT (context);
2895 * g_main_context_pending:
2896 * @context: a #GMainContext (if %NULL, the default context will be used)
2898 * Checks if any sources have pending events for the given context.
2900 * Return value: %TRUE if events are pending.
2903 g_main_context_pending (GMainContext *context)
2908 context = g_main_context_default();
2910 LOCK_CONTEXT (context);
2911 retval = g_main_context_iterate (context, FALSE, FALSE, G_THREAD_SELF);
2912 UNLOCK_CONTEXT (context);
2918 * g_main_context_iteration:
2919 * @context: a #GMainContext (if %NULL, the default context will be used)
2920 * @may_block: whether the call may block.
2922 * Runs a single iteration for the given main loop. This involves
2923 * checking to see if any event sources are ready to be processed,
2924 * then if no events sources are ready and @may_block is %TRUE, waiting
2925 * for a source to become ready, then dispatching the highest priority
2926 * events sources that are ready. Otherwise, if @may_block is %FALSE
2927 * sources are not waited to become ready, only those highest priority
2928 * events sources will be dispatched (if any), that are ready at this
2929 * given moment without further waiting.
2931 * Note that even when @may_block is %TRUE, it is still possible for
2932 * g_main_context_iteration() to return %FALSE, since the the wait may
2933 * be interrupted for other reasons than an event source becoming ready.
2935 * Return value: %TRUE if events were dispatched.
2938 g_main_context_iteration (GMainContext *context, gboolean may_block)
2943 context = g_main_context_default();
2945 LOCK_CONTEXT (context);
2946 retval = g_main_context_iterate (context, may_block, TRUE, G_THREAD_SELF);
2947 UNLOCK_CONTEXT (context);
2954 * @context: a #GMainContext (if %NULL, the default context will be used).
2955 * @is_running: set to %TRUE to indicate that the loop is running. This
2956 * is not very important since calling g_main_loop_run() will set this to
2959 * Creates a new #GMainLoop structure.
2961 * Return value: a new #GMainLoop.
2964 g_main_loop_new (GMainContext *context,
2965 gboolean is_running)
2970 context = g_main_context_default();
2972 g_main_context_ref (context);
2974 loop = g_new0 (GMainLoop, 1);
2975 loop->context = context;
2976 loop->is_running = is_running != FALSE;
2977 loop->ref_count = 1;
2984 * @loop: a #GMainLoop
2986 * Increases the reference count on a #GMainLoop object by one.
2988 * Return value: @loop
2991 g_main_loop_ref (GMainLoop *loop)
2993 g_return_val_if_fail (loop != NULL, NULL);
2994 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
2996 g_atomic_int_inc (&loop->ref_count);
3002 * g_main_loop_unref:
3003 * @loop: a #GMainLoop
3005 * Decreases the reference count on a #GMainLoop object by one. If
3006 * the result is zero, free the loop and free all associated memory.
3009 g_main_loop_unref (GMainLoop *loop)
3011 g_return_if_fail (loop != NULL);
3012 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3014 if (!g_atomic_int_dec_and_test (&loop->ref_count))
3017 g_main_context_unref (loop->context);
3023 * @loop: a #GMainLoop
3025 * Runs a main loop until g_main_loop_quit() is called on the loop.
3026 * If this is called for the thread of the loop's #GMainContext,
3027 * it will process events from the loop, otherwise it will
3031 g_main_loop_run (GMainLoop *loop)
3033 GThread *self = G_THREAD_SELF;
3035 g_return_if_fail (loop != NULL);
3036 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3038 #ifdef G_THREADS_ENABLED
3039 if (!g_main_context_acquire (loop->context))
3041 gboolean got_ownership = FALSE;
3043 /* Another thread owns this context */
3044 if (!g_thread_supported ())
3046 g_warning ("g_main_loop_run() was called from second thread but "
3047 "g_thread_init() was never called.");
3051 LOCK_CONTEXT (loop->context);
3053 g_atomic_int_inc (&loop->ref_count);
3055 if (!loop->is_running)
3056 loop->is_running = TRUE;
3058 if (!loop->context->cond)
3059 loop->context->cond = g_cond_new ();
3061 while (loop->is_running && !got_ownership)
3062 got_ownership = g_main_context_wait (loop->context,
3063 loop->context->cond,
3064 g_static_mutex_get_mutex (&loop->context->mutex));
3066 if (!loop->is_running)
3068 UNLOCK_CONTEXT (loop->context);
3070 g_main_context_release (loop->context);
3071 g_main_loop_unref (loop);
3075 g_assert (got_ownership);
3078 LOCK_CONTEXT (loop->context);
3079 #endif /* G_THREADS_ENABLED */
3081 if (loop->context->in_check_or_prepare)
3083 g_warning ("g_main_loop_run(): called recursively from within a source's "
3084 "check() or prepare() member, iteration not possible.");
3088 g_atomic_int_inc (&loop->ref_count);
3089 loop->is_running = TRUE;
3090 while (loop->is_running)
3091 g_main_context_iterate (loop->context, TRUE, TRUE, self);
3093 UNLOCK_CONTEXT (loop->context);
3095 #ifdef G_THREADS_ENABLED
3096 g_main_context_release (loop->context);
3097 #endif /* G_THREADS_ENABLED */
3099 g_main_loop_unref (loop);
3104 * @loop: a #GMainLoop
3106 * Stops a #GMainLoop from running. Any calls to g_main_loop_run()
3107 * for the loop will return.
3109 * Note that sources that have already been dispatched when
3110 * g_main_loop_quit() is called will still be executed.
3113 g_main_loop_quit (GMainLoop *loop)
3115 g_return_if_fail (loop != NULL);
3116 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
3118 LOCK_CONTEXT (loop->context);
3119 loop->is_running = FALSE;
3120 g_main_context_wakeup_unlocked (loop->context);
3122 #ifdef G_THREADS_ENABLED
3123 if (loop->context->cond)
3124 g_cond_broadcast (loop->context->cond);
3125 #endif /* G_THREADS_ENABLED */
3127 UNLOCK_CONTEXT (loop->context);
3131 * g_main_loop_is_running:
3132 * @loop: a #GMainLoop.
3134 * Checks to see if the main loop is currently being run via g_main_loop_run().
3136 * Return value: %TRUE if the mainloop is currently being run.
3139 g_main_loop_is_running (GMainLoop *loop)
3141 g_return_val_if_fail (loop != NULL, FALSE);
3142 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, FALSE);
3144 return loop->is_running;
3148 * g_main_loop_get_context:
3149 * @loop: a #GMainLoop.
3151 * Returns the #GMainContext of @loop.
3153 * Return value: the #GMainContext of @loop
3156 g_main_loop_get_context (GMainLoop *loop)
3158 g_return_val_if_fail (loop != NULL, NULL);
3159 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
3161 return loop->context;
3164 /* HOLDS: context's lock */
3166 g_main_context_poll (GMainContext *context,
3172 #ifdef G_MAIN_POLL_DEBUG
3178 GPollFunc poll_func;
3180 if (n_fds || timeout != 0)
3182 #ifdef G_MAIN_POLL_DEBUG
3183 if (_g_main_poll_debug)
3185 g_print ("polling context=%p n=%d timeout=%d\n",
3186 context, n_fds, timeout);
3187 poll_timer = g_timer_new ();
3191 LOCK_CONTEXT (context);
3193 poll_func = context->poll_func;
3195 UNLOCK_CONTEXT (context);
3196 if ((*poll_func) (fds, n_fds, timeout) < 0 && errno != EINTR)
3199 g_warning ("poll(2) failed due to: %s.",
3200 g_strerror (errno));
3202 /* If g_poll () returns -1, it has already called g_warning() */
3206 #ifdef G_MAIN_POLL_DEBUG
3207 if (_g_main_poll_debug)
3209 LOCK_CONTEXT (context);
3211 g_print ("g_main_poll(%d) timeout: %d - elapsed %12.10f seconds",
3214 g_timer_elapsed (poll_timer, NULL));
3215 g_timer_destroy (poll_timer);
3216 pollrec = context->poll_records;
3218 while (pollrec != NULL)
3223 if (fds[i].fd == pollrec->fd->fd &&
3224 pollrec->fd->events &&
3227 g_print (" [" G_POLLFD_FORMAT " :", fds[i].fd);
3228 if (fds[i].revents & G_IO_IN)
3230 if (fds[i].revents & G_IO_OUT)
3232 if (fds[i].revents & G_IO_PRI)
3234 if (fds[i].revents & G_IO_ERR)
3236 if (fds[i].revents & G_IO_HUP)
3238 if (fds[i].revents & G_IO_NVAL)
3244 pollrec = pollrec->next;
3248 UNLOCK_CONTEXT (context);
3251 } /* if (n_fds || timeout != 0) */
3255 * g_main_context_add_poll:
3256 * @context: a #GMainContext (or %NULL for the default context)
3257 * @fd: a #GPollFD structure holding information about a file
3258 * descriptor to watch.
3259 * @priority: the priority for this file descriptor which should be
3260 * the same as the priority used for g_source_attach() to ensure that the
3261 * file descriptor is polled whenever the results may be needed.
3263 * Adds a file descriptor to the set of file descriptors polled for
3264 * this context. This will very seldomly be used directly. Instead
3265 * a typical event source will use g_source_add_poll() instead.
3268 g_main_context_add_poll (GMainContext *context,
3273 context = g_main_context_default ();
3275 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3276 g_return_if_fail (fd);
3278 LOCK_CONTEXT (context);
3279 g_main_context_add_poll_unlocked (context, priority, fd);
3280 UNLOCK_CONTEXT (context);
3283 /* HOLDS: main_loop_lock */
3285 g_main_context_add_poll_unlocked (GMainContext *context,
3289 GPollRec *lastrec, *pollrec;
3290 GPollRec *newrec = g_slice_new (GPollRec);
3292 /* This file descriptor may be checked before we ever poll */
3295 newrec->priority = priority;
3298 pollrec = context->poll_records;
3299 while (pollrec && priority >= pollrec->priority)
3302 pollrec = pollrec->next;
3306 lastrec->next = newrec;
3308 context->poll_records = newrec;
3310 newrec->next = pollrec;
3312 context->n_poll_records++;
3314 #ifdef G_THREADS_ENABLED
3315 context->poll_changed = TRUE;
3317 /* Now wake up the main loop if it is waiting in the poll() */
3318 g_main_context_wakeup_unlocked (context);
3323 * g_main_context_remove_poll:
3324 * @context:a #GMainContext
3325 * @fd: a #GPollFD descriptor previously added with g_main_context_add_poll()
3327 * Removes file descriptor from the set of file descriptors to be
3328 * polled for a particular context.
3331 g_main_context_remove_poll (GMainContext *context,
3335 context = g_main_context_default ();
3337 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3338 g_return_if_fail (fd);
3340 LOCK_CONTEXT (context);
3341 g_main_context_remove_poll_unlocked (context, fd);
3342 UNLOCK_CONTEXT (context);
3346 g_main_context_remove_poll_unlocked (GMainContext *context,
3349 GPollRec *pollrec, *lastrec;
3352 pollrec = context->poll_records;
3356 if (pollrec->fd == fd)
3358 if (lastrec != NULL)
3359 lastrec->next = pollrec->next;
3361 context->poll_records = pollrec->next;
3363 g_slice_free (GPollRec, pollrec);
3365 context->n_poll_records--;
3369 pollrec = pollrec->next;
3372 #ifdef G_THREADS_ENABLED
3373 context->poll_changed = TRUE;
3375 /* Now wake up the main loop if it is waiting in the poll() */
3376 g_main_context_wakeup_unlocked (context);
3381 * g_source_get_current_time:
3382 * @source: a #GSource
3383 * @timeval: #GTimeVal structure in which to store current time.
3385 * Gets the "current time" to be used when checking
3386 * this source. The advantage of calling this function over
3387 * calling g_get_current_time() directly is that when
3388 * checking multiple sources, GLib can cache a single value
3389 * instead of having to repeatedly get the system time.
3391 * Deprecated: 2.28: use g_source_get_time() instead
3394 g_source_get_current_time (GSource *source,
3397 GMainContext *context;
3399 g_return_if_fail (source->context != NULL);
3401 context = source->context;
3403 LOCK_CONTEXT (context);
3405 if (!context->current_time_is_fresh)
3407 g_get_current_time (&context->current_time);
3408 context->current_time_is_fresh = TRUE;
3411 *timeval = context->current_time;
3413 UNLOCK_CONTEXT (context);
3417 * g_source_get_time:
3418 * @source: a #GSource
3420 * Gets the time to be used when checking this source. The advantage of
3421 * calling this function over calling g_get_monotonic_time() directly is
3422 * that when checking multiple sources, GLib can cache a single value
3423 * instead of having to repeatedly get the system monotonic time.
3425 * The time here is the system monotonic time, if available, or some
3426 * other reasonable alternative otherwise. See g_get_monotonic_time().
3428 * Returns: the monotonic time in microseconds
3433 g_source_get_time (GSource *source)
3435 GMainContext *context;
3438 g_return_val_if_fail (source->context != NULL, 0);
3440 context = source->context;
3442 LOCK_CONTEXT (context);
3444 if (!context->time_is_fresh)
3446 context->time = g_get_monotonic_time ();
3447 context->time_is_fresh = TRUE;
3450 result = context->time;
3452 UNLOCK_CONTEXT (context);
3458 * g_main_context_set_poll_func:
3459 * @context: a #GMainContext
3460 * @func: the function to call to poll all file descriptors
3462 * Sets the function to use to handle polling of file descriptors. It
3463 * will be used instead of the poll() system call
3464 * (or GLib's replacement function, which is used where
3465 * poll() isn't available).
3467 * This function could possibly be used to integrate the GLib event
3468 * loop with an external event loop.
3471 g_main_context_set_poll_func (GMainContext *context,
3475 context = g_main_context_default ();
3477 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3479 LOCK_CONTEXT (context);
3482 context->poll_func = func;
3484 context->poll_func = g_poll;
3486 UNLOCK_CONTEXT (context);
3490 * g_main_context_get_poll_func:
3491 * @context: a #GMainContext
3493 * Gets the poll function set by g_main_context_set_poll_func().
3495 * Return value: the poll function
3498 g_main_context_get_poll_func (GMainContext *context)
3503 context = g_main_context_default ();
3505 g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL);
3507 LOCK_CONTEXT (context);
3508 result = context->poll_func;
3509 UNLOCK_CONTEXT (context);
3514 /* HOLDS: context's lock */
3515 /* Wake the main loop up from a poll() */
3517 g_main_context_wakeup_unlocked (GMainContext *context)
3519 #ifdef G_THREADS_ENABLED
3520 if (g_thread_supported() && context->poll_waiting)
3522 context->poll_waiting = FALSE;
3524 write (context->wake_up_pipe[1], "A", 1);
3526 ReleaseSemaphore (context->wake_up_semaphore, 1, NULL);
3533 * g_main_context_wakeup:
3534 * @context: a #GMainContext
3536 * If @context is currently waiting in a poll(), interrupt
3537 * the poll(), and continue the iteration process.
3540 g_main_context_wakeup (GMainContext *context)
3543 context = g_main_context_default ();
3545 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3547 LOCK_CONTEXT (context);
3548 g_main_context_wakeup_unlocked (context);
3549 UNLOCK_CONTEXT (context);
3553 * g_main_context_is_owner:
3554 * @context: a #GMainContext
3556 * Determines whether this thread holds the (recursive)
3557 * ownership of this #GMaincontext. This is useful to
3558 * know before waiting on another thread that may be
3559 * blocking to get ownership of @context.
3561 * Returns: %TRUE if current thread is owner of @context.
3566 g_main_context_is_owner (GMainContext *context)
3571 context = g_main_context_default ();
3573 #ifdef G_THREADS_ENABLED
3574 LOCK_CONTEXT (context);
3575 is_owner = context->owner == G_THREAD_SELF;
3576 UNLOCK_CONTEXT (context);
3587 g_timeout_set_expiration (GTimeoutSource *timeout_source,
3588 gint64 current_time)
3590 timeout_source->expiration = current_time + timeout_source->interval * 1000;
3592 if (timeout_source->seconds)
3594 static gint timer_perturb = -1;
3596 if (timer_perturb == -1)
3599 * we want a per machine/session unique 'random' value; try the dbus
3600 * address first, that has a UUID in it. If there is no dbus, use the
3601 * hostname for hashing.
3603 const char *session_bus_address = g_getenv ("DBUS_SESSION_BUS_ADDRESS");
3604 if (!session_bus_address)
3605 session_bus_address = g_getenv ("HOSTNAME");
3606 if (session_bus_address)
3607 timer_perturb = ABS ((gint) g_str_hash (session_bus_address)) % 1000000;
3612 /* We want the microseconds part of the timeout to land on the
3613 * 'timer_perturb' mark, but we need to make sure we don't try to
3614 * set the timeout in the past. We do this by ensuring that we
3615 * always only *increase* the expiration time by adding a full
3616 * second in the case that the microsecond portion decreases.
3618 if (timer_perturb < timeout_source->expiration % 1000000)
3619 timeout_source->expiration += 1000000;
3621 timeout_source->expiration =
3622 ((timeout_source->expiration / 1000000) * 1000000) + timer_perturb;
3627 g_timeout_prepare (GSource *source,
3630 GTimeoutSource *timeout_source = (GTimeoutSource *) source;
3631 gint64 now = g_source_get_time (source);
3633 if (now < timeout_source->expiration)
3635 /* Round up to ensure that we don't try again too early */
3636 *timeout = (timeout_source->expiration - now + 999) / 1000;
3645 g_timeout_check (GSource *source)
3647 GTimeoutSource *timeout_source = (GTimeoutSource *) source;
3648 gint64 now = g_source_get_time (source);
3650 return timeout_source->expiration <= now;
3654 g_timeout_dispatch (GSource *source,
3655 GSourceFunc callback,
3658 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3663 g_warning ("Timeout source dispatched without callback\n"
3664 "You must call g_source_set_callback().");
3668 again = callback (user_data);
3671 g_timeout_set_expiration (timeout_source, g_source_get_time (source));
3677 * g_timeout_source_new:
3678 * @interval: the timeout interval in milliseconds.
3680 * Creates a new timeout source.
3682 * The source will not initially be associated with any #GMainContext
3683 * and must be added to one with g_source_attach() before it will be
3686 * Return value: the newly-created timeout source
3689 g_timeout_source_new (guint interval)
3691 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
3692 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3694 timeout_source->interval = interval;
3695 g_timeout_set_expiration (timeout_source, g_get_monotonic_time ());
3701 * g_timeout_source_new_seconds:
3702 * @interval: the timeout interval in seconds
3704 * Creates a new timeout source.
3706 * The source will not initially be associated with any #GMainContext
3707 * and must be added to one with g_source_attach() before it will be
3710 * The scheduling granularity/accuracy of this timeout source will be
3713 * Return value: the newly-created timeout source
3718 g_timeout_source_new_seconds (guint interval)
3720 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
3721 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3723 timeout_source->interval = 1000 * interval;
3724 timeout_source->seconds = TRUE;
3726 g_timeout_set_expiration (timeout_source, g_get_monotonic_time ());
3733 * g_timeout_add_full:
3734 * @priority: the priority of the timeout source. Typically this will be in
3735 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
3736 * @interval: the time between calls to the function, in milliseconds
3737 * (1/1000ths of a second)
3738 * @function: function to call
3739 * @data: data to pass to @function
3740 * @notify: function to call when the timeout is removed, or %NULL
3742 * Sets a function to be called at regular intervals, with the given
3743 * priority. The function is called repeatedly until it returns
3744 * %FALSE, at which point the timeout is automatically destroyed and
3745 * the function will not be called again. The @notify function is
3746 * called when the timeout is destroyed. The first call to the
3747 * function will be at the end of the first @interval.
3749 * Note that timeout functions may be delayed, due to the processing of other
3750 * event sources. Thus they should not be relied on for precise timing.
3751 * After each call to the timeout function, the time of the next
3752 * timeout is recalculated based on the current time and the given interval
3753 * (it does not try to 'catch up' time lost in delays).
3755 * This internally creates a main loop source using g_timeout_source_new()
3756 * and attaches it to the main loop context using g_source_attach(). You can
3757 * do these steps manually if you need greater control.
3759 * Return value: the ID (greater than 0) of the event source.
3762 g_timeout_add_full (gint priority,
3764 GSourceFunc function,
3766 GDestroyNotify notify)
3771 g_return_val_if_fail (function != NULL, 0);
3773 source = g_timeout_source_new (interval);
3775 if (priority != G_PRIORITY_DEFAULT)
3776 g_source_set_priority (source, priority);
3778 g_source_set_callback (source, function, data, notify);
3779 id = g_source_attach (source, NULL);
3780 g_source_unref (source);
3787 * @interval: the time between calls to the function, in milliseconds
3788 * (1/1000ths of a second)
3789 * @function: function to call
3790 * @data: data to pass to @function
3792 * Sets a function to be called at regular intervals, with the default
3793 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly
3794 * until it returns %FALSE, at which point the timeout is automatically
3795 * destroyed and the function will not be called again. The first call
3796 * to the function will be at the end of the first @interval.
3798 * Note that timeout functions may be delayed, due to the processing of other
3799 * event sources. Thus they should not be relied on for precise timing.
3800 * After each call to the timeout function, the time of the next
3801 * timeout is recalculated based on the current time and the given interval
3802 * (it does not try to 'catch up' time lost in delays).
3804 * If you want to have a timer in the "seconds" range and do not care
3805 * about the exact time of the first call of the timer, use the
3806 * g_timeout_add_seconds() function; this function allows for more
3807 * optimizations and more efficient system power usage.
3809 * This internally creates a main loop source using g_timeout_source_new()
3810 * and attaches it to the main loop context using g_source_attach(). You can
3811 * do these steps manually if you need greater control.
3813 * Return value: the ID (greater than 0) of the event source.
3816 g_timeout_add (guint32 interval,
3817 GSourceFunc function,
3820 return g_timeout_add_full (G_PRIORITY_DEFAULT,
3821 interval, function, data, NULL);
3825 * g_timeout_add_seconds_full:
3826 * @priority: the priority of the timeout source. Typically this will be in
3827 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
3828 * @interval: the time between calls to the function, in seconds
3829 * @function: function to call
3830 * @data: data to pass to @function
3831 * @notify: function to call when the timeout is removed, or %NULL
3833 * Sets a function to be called at regular intervals, with @priority.
3834 * The function is called repeatedly until it returns %FALSE, at which
3835 * point the timeout is automatically destroyed and the function will
3836 * not be called again.
3838 * Unlike g_timeout_add(), this function operates at whole second granularity.
3839 * The initial starting point of the timer is determined by the implementation
3840 * and the implementation is expected to group multiple timers together so that
3841 * they fire all at the same time.
3842 * To allow this grouping, the @interval to the first timer is rounded
3843 * and can deviate up to one second from the specified interval.
3844 * Subsequent timer iterations will generally run at the specified interval.
3846 * Note that timeout functions may be delayed, due to the processing of other
3847 * event sources. Thus they should not be relied on for precise timing.
3848 * After each call to the timeout function, the time of the next
3849 * timeout is recalculated based on the current time and the given @interval
3851 * If you want timing more precise than whole seconds, use g_timeout_add()
3854 * The grouping of timers to fire at the same time results in a more power
3855 * and CPU efficient behavior so if your timer is in multiples of seconds
3856 * and you don't require the first timer exactly one second from now, the
3857 * use of g_timeout_add_seconds() is preferred over g_timeout_add().
3859 * This internally creates a main loop source using
3860 * g_timeout_source_new_seconds() and attaches it to the main loop context
3861 * using g_source_attach(). You can do these steps manually if you need
3864 * Return value: the ID (greater than 0) of the event source.
3869 g_timeout_add_seconds_full (gint priority,
3871 GSourceFunc function,
3873 GDestroyNotify notify)
3878 g_return_val_if_fail (function != NULL, 0);
3880 source = g_timeout_source_new_seconds (interval);
3882 if (priority != G_PRIORITY_DEFAULT)
3883 g_source_set_priority (source, priority);
3885 g_source_set_callback (source, function, data, notify);
3886 id = g_source_attach (source, NULL);
3887 g_source_unref (source);
3893 * g_timeout_add_seconds:
3894 * @interval: the time between calls to the function, in seconds
3895 * @function: function to call
3896 * @data: data to pass to @function
3898 * Sets a function to be called at regular intervals with the default
3899 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly until
3900 * it returns %FALSE, at which point the timeout is automatically destroyed
3901 * and the function will not be called again.
3903 * This internally creates a main loop source using
3904 * g_timeout_source_new_seconds() and attaches it to the main loop context
3905 * using g_source_attach(). You can do these steps manually if you need
3906 * greater control. Also see g_timout_add_seconds_full().
3908 * Return value: the ID (greater than 0) of the event source.
3913 g_timeout_add_seconds (guint interval,
3914 GSourceFunc function,
3917 g_return_val_if_fail (function != NULL, 0);
3919 return g_timeout_add_seconds_full (G_PRIORITY_DEFAULT, interval, function, data, NULL);
3922 /* Child watch functions */
3927 g_child_watch_prepare (GSource *source,
3936 g_child_watch_check (GSource *source)
3938 GChildWatchSource *child_watch_source;
3939 gboolean child_exited;
3941 child_watch_source = (GChildWatchSource *) source;
3943 child_exited = child_watch_source->poll.revents & G_IO_IN;
3950 * Note: We do _not_ check for the special value of STILL_ACTIVE
3951 * since we know that the process has exited and doing so runs into
3952 * problems if the child process "happens to return STILL_ACTIVE(259)"
3953 * as Microsoft's Platform SDK puts it.
3955 if (!GetExitCodeProcess (child_watch_source->pid, &child_status))
3957 gchar *emsg = g_win32_error_message (GetLastError ());
3958 g_warning (G_STRLOC ": GetExitCodeProcess() failed: %s", emsg);
3961 child_watch_source->child_status = -1;
3964 child_watch_source->child_status = child_status;
3967 return child_exited;
3970 #else /* G_OS_WIN32 */
3973 check_for_child_exited (GSource *source)
3975 GChildWatchSource *child_watch_source;
3978 /* protect against another SIGCHLD in the middle of this call */
3979 count = child_watch_count;
3981 child_watch_source = (GChildWatchSource *) source;
3983 if (child_watch_source->child_exited)
3986 if (child_watch_source->count < count)
3990 if (waitpid (child_watch_source->pid, &child_status, WNOHANG) > 0)
3992 child_watch_source->child_status = child_status;
3993 child_watch_source->child_exited = TRUE;
3995 child_watch_source->count = count;
3998 return child_watch_source->child_exited;
4002 g_child_watch_prepare (GSource *source,
4007 return check_for_child_exited (source);
4012 g_child_watch_check (GSource *source)
4014 return check_for_child_exited (source);
4017 #endif /* G_OS_WIN32 */
4020 g_child_watch_dispatch (GSource *source,
4021 GSourceFunc callback,
4024 GChildWatchSource *child_watch_source;
4025 GChildWatchFunc child_watch_callback = (GChildWatchFunc) callback;
4027 child_watch_source = (GChildWatchSource *) source;
4031 g_warning ("Child watch source dispatched without callback\n"
4032 "You must call g_source_set_callback().");
4036 (child_watch_callback) (child_watch_source->pid, child_watch_source->child_status, user_data);
4038 /* We never keep a child watch source around as the child is gone */
4045 g_child_watch_signal_handler (int signum)
4047 child_watch_count ++;
4049 if (child_watch_init_state == CHILD_WATCH_INITIALIZED_THREADED)
4051 write (child_watch_wake_up_pipe[1], "B", 1);
4055 /* We count on the signal interrupting the poll in the same thread.
4061 g_child_watch_source_init_single (void)
4063 struct sigaction action;
4065 g_assert (! g_thread_supported());
4066 g_assert (child_watch_init_state == CHILD_WATCH_UNINITIALIZED);
4068 child_watch_init_state = CHILD_WATCH_INITIALIZED_SINGLE;
4070 action.sa_handler = g_child_watch_signal_handler;
4071 sigemptyset (&action.sa_mask);
4072 action.sa_flags = SA_NOCLDSTOP;
4073 sigaction (SIGCHLD, &action, NULL);
4076 G_GNUC_NORETURN static gpointer
4077 child_watch_helper_thread (gpointer data)
4084 read (child_watch_wake_up_pipe[0], b, 20);
4086 /* We were woken up. Wake up all other contexts in all other threads */
4087 G_LOCK (main_context_list);
4088 for (list = main_context_list; list; list = list->next)
4090 GMainContext *context;
4092 context = list->data;
4093 if (g_atomic_int_get (&context->ref_count) > 0)
4094 /* Due to racing conditions we can find ref_count == 0, in
4095 * that case, however, the context is still not destroyed
4096 * and no poll can be active, otherwise the ref_count
4098 g_main_context_wakeup (context);
4100 G_UNLOCK (main_context_list);
4105 g_child_watch_source_init_multi_threaded (void)
4107 GError *error = NULL;
4108 struct sigaction action;
4110 g_assert (g_thread_supported());
4112 if (pipe (child_watch_wake_up_pipe) < 0)
4113 g_error ("Cannot create wake up pipe: %s\n", g_strerror (errno));
4114 fcntl (child_watch_wake_up_pipe[1], F_SETFL, O_NONBLOCK | fcntl (child_watch_wake_up_pipe[1], F_GETFL));
4116 /* We create a helper thread that polls on the wakeup pipe indefinitely */
4117 /* FIXME: Think this through for races */
4118 if (g_thread_create (child_watch_helper_thread, NULL, FALSE, &error) == NULL)
4119 g_error ("Cannot create a thread to monitor child exit status: %s\n", error->message);
4120 child_watch_init_state = CHILD_WATCH_INITIALIZED_THREADED;
4122 action.sa_handler = g_child_watch_signal_handler;
4123 sigemptyset (&action.sa_mask);
4124 action.sa_flags = SA_RESTART | SA_NOCLDSTOP;
4125 sigaction (SIGCHLD, &action, NULL);
4129 g_child_watch_source_init_promote_single_to_threaded (void)
4131 g_child_watch_source_init_multi_threaded ();
4135 g_child_watch_source_init (void)
4137 if (g_thread_supported())
4139 if (child_watch_init_state == CHILD_WATCH_UNINITIALIZED)
4140 g_child_watch_source_init_multi_threaded ();
4141 else if (child_watch_init_state == CHILD_WATCH_INITIALIZED_SINGLE)
4142 g_child_watch_source_init_promote_single_to_threaded ();
4146 if (child_watch_init_state == CHILD_WATCH_UNINITIALIZED)
4147 g_child_watch_source_init_single ();
4151 #endif /* !G_OS_WIN32 */
4154 * g_child_watch_source_new:
4155 * @pid: process to watch. On POSIX the pid of a child process. On
4156 * Windows a handle for a process (which doesn't have to be a child).
4158 * Creates a new child_watch source.
4160 * The source will not initially be associated with any #GMainContext
4161 * and must be added to one with g_source_attach() before it will be
4164 * Note that child watch sources can only be used in conjunction with
4165 * <literal>g_spawn...</literal> when the %G_SPAWN_DO_NOT_REAP_CHILD
4168 * Note that on platforms where #GPid must be explicitly closed
4169 * (see g_spawn_close_pid()) @pid must not be closed while the
4170 * source is still active. Typically, you will want to call
4171 * g_spawn_close_pid() in the callback function for the source.
4173 * Note further that using g_child_watch_source_new() is not
4174 * compatible with calling <literal>waitpid(-1)</literal> in
4175 * the application. Calling waitpid() for individual pids will
4178 * Return value: the newly-created child watch source
4183 g_child_watch_source_new (GPid pid)
4185 GSource *source = g_source_new (&g_child_watch_funcs, sizeof (GChildWatchSource));
4186 GChildWatchSource *child_watch_source = (GChildWatchSource *)source;
4189 child_watch_source->poll.fd = (gintptr) pid;
4190 child_watch_source->poll.events = G_IO_IN;
4192 g_source_add_poll (source, &child_watch_source->poll);
4193 #else /* G_OS_WIN32 */
4194 g_child_watch_source_init ();
4195 #endif /* G_OS_WIN32 */
4197 child_watch_source->pid = pid;
4203 * g_child_watch_add_full:
4204 * @priority: the priority of the idle source. Typically this will be in the
4205 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
4206 * @pid: process to watch. On POSIX the pid of a child process. On
4207 * Windows a handle for a process (which doesn't have to be a child).
4208 * @function: function to call
4209 * @data: data to pass to @function
4210 * @notify: function to call when the idle is removed, or %NULL
4212 * Sets a function to be called when the child indicated by @pid
4213 * exits, at the priority @priority.
4215 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
4216 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
4217 * the spawn function for the child watching to work.
4219 * Note that on platforms where #GPid must be explicitly closed
4220 * (see g_spawn_close_pid()) @pid must not be closed while the
4221 * source is still active. Typically, you will want to call
4222 * g_spawn_close_pid() in the callback function for the source.
4224 * GLib supports only a single callback per process id.
4226 * This internally creates a main loop source using
4227 * g_child_watch_source_new() and attaches it to the main loop context
4228 * using g_source_attach(). You can do these steps manually if you
4229 * need greater control.
4231 * Return value: the ID (greater than 0) of the event source.
4236 g_child_watch_add_full (gint priority,
4238 GChildWatchFunc function,
4240 GDestroyNotify notify)
4245 g_return_val_if_fail (function != NULL, 0);
4247 source = g_child_watch_source_new (pid);
4249 if (priority != G_PRIORITY_DEFAULT)
4250 g_source_set_priority (source, priority);
4252 g_source_set_callback (source, (GSourceFunc) function, data, notify);
4253 id = g_source_attach (source, NULL);
4254 g_source_unref (source);
4260 * g_child_watch_add:
4261 * @pid: process id to watch. On POSIX the pid of a child process. On
4262 * Windows a handle for a process (which doesn't have to be a child).
4263 * @function: function to call
4264 * @data: data to pass to @function
4266 * Sets a function to be called when the child indicated by @pid
4267 * exits, at a default priority, #G_PRIORITY_DEFAULT.
4269 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
4270 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
4271 * the spawn function for the child watching to work.
4273 * Note that on platforms where #GPid must be explicitly closed
4274 * (see g_spawn_close_pid()) @pid must not be closed while the
4275 * source is still active. Typically, you will want to call
4276 * g_spawn_close_pid() in the callback function for the source.
4278 * GLib supports only a single callback per process id.
4280 * This internally creates a main loop source using
4281 * g_child_watch_source_new() and attaches it to the main loop context
4282 * using g_source_attach(). You can do these steps manually if you
4283 * need greater control.
4285 * Return value: the ID (greater than 0) of the event source.
4290 g_child_watch_add (GPid pid,
4291 GChildWatchFunc function,
4294 return g_child_watch_add_full (G_PRIORITY_DEFAULT, pid, function, data, NULL);
4298 /* Idle functions */
4301 g_idle_prepare (GSource *source,
4310 g_idle_check (GSource *source)
4316 g_idle_dispatch (GSource *source,
4317 GSourceFunc callback,
4322 g_warning ("Idle source dispatched without callback\n"
4323 "You must call g_source_set_callback().");
4327 return callback (user_data);
4331 * g_idle_source_new:
4333 * Creates a new idle source.
4335 * The source will not initially be associated with any #GMainContext
4336 * and must be added to one with g_source_attach() before it will be
4337 * executed. Note that the default priority for idle sources is
4338 * %G_PRIORITY_DEFAULT_IDLE, as compared to other sources which
4339 * have a default priority of %G_PRIORITY_DEFAULT.
4341 * Return value: the newly-created idle source
4344 g_idle_source_new (void)
4348 source = g_source_new (&g_idle_funcs, sizeof (GSource));
4349 g_source_set_priority (source, G_PRIORITY_DEFAULT_IDLE);
4356 * @priority: the priority of the idle source. Typically this will be in the
4357 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
4358 * @function: function to call
4359 * @data: data to pass to @function
4360 * @notify: function to call when the idle is removed, or %NULL
4362 * Adds a function to be called whenever there are no higher priority
4363 * events pending. If the function returns %FALSE it is automatically
4364 * removed from the list of event sources and will not be called again.
4366 * This internally creates a main loop source using g_idle_source_new()
4367 * and attaches it to the main loop context using g_source_attach().
4368 * You can do these steps manually if you need greater control.
4370 * Return value: the ID (greater than 0) of the event source.
4373 g_idle_add_full (gint priority,
4374 GSourceFunc function,
4376 GDestroyNotify notify)
4381 g_return_val_if_fail (function != NULL, 0);
4383 source = g_idle_source_new ();
4385 if (priority != G_PRIORITY_DEFAULT_IDLE)
4386 g_source_set_priority (source, priority);
4388 g_source_set_callback (source, function, data, notify);
4389 id = g_source_attach (source, NULL);
4390 g_source_unref (source);
4397 * @function: function to call
4398 * @data: data to pass to @function.
4400 * Adds a function to be called whenever there are no higher priority
4401 * events pending to the default main loop. The function is given the
4402 * default idle priority, #G_PRIORITY_DEFAULT_IDLE. If the function
4403 * returns %FALSE it is automatically removed from the list of event
4404 * sources and will not be called again.
4406 * This internally creates a main loop source using g_idle_source_new()
4407 * and attaches it to the main loop context using g_source_attach().
4408 * You can do these steps manually if you need greater control.
4410 * Return value: the ID (greater than 0) of the event source.
4413 g_idle_add (GSourceFunc function,
4416 return g_idle_add_full (G_PRIORITY_DEFAULT_IDLE, function, data, NULL);
4420 * g_idle_remove_by_data:
4421 * @data: the data for the idle source's callback.
4423 * Removes the idle function with the given data.
4425 * Return value: %TRUE if an idle source was found and removed.
4428 g_idle_remove_by_data (gpointer data)
4430 return g_source_remove_by_funcs_user_data (&g_idle_funcs, data);
4434 * g_main_context_invoke:
4435 * @context: a #GMainContext, or %NULL
4436 * @function: function to call
4437 * @data: data to pass to @function
4439 * Invokes a function in such a way that @context is owned during the
4440 * invocation of @function.
4442 * If @context is %NULL then the global default main context — as
4443 * returned by g_main_context_default() — is used.
4445 * If @context is owned by the current thread, @function is called
4446 * directly. Otherwise, if @context is the thread-default main context
4447 * of the current thread and g_main_context_acquire() succeeds, then
4448 * @function is called and g_main_context_release() is called
4451 * In any other case, an idle source is created to call @function and
4452 * that source is attached to @context (presumably to be run in another
4453 * thread). The idle source is attached with #G_PRIORITY_DEFAULT
4454 * priority. If you want a different priority, use
4455 * g_main_context_invoke_full().
4457 * Note that, as with normal idle functions, @function should probably
4458 * return %FALSE. If it returns %TRUE, it will be continuously run in a
4459 * loop (and may prevent this call from returning).
4464 g_main_context_invoke (GMainContext *context,
4465 GSourceFunc function,
4468 g_main_context_invoke_full (context,
4470 function, data, NULL);
4474 * g_main_context_invoke_full:
4475 * @context: a #GMainContext, or %NULL
4476 * @priority: the priority at which to run @function
4477 * @function: function to call
4478 * @data: data to pass to @function
4479 * @notify: a function to call when @data is no longer in use, or %NULL.
4481 * Invokes a function in such a way that @context is owned during the
4482 * invocation of @function.
4484 * This function is the same as g_main_context_invoke() except that it
4485 * lets you specify the priority incase @function ends up being
4486 * scheduled as an idle and also lets you give a #GDestroyNotify for @data.
4488 * @notify should not assume that it is called from any particular
4489 * thread or with any particular context acquired.
4494 g_main_context_invoke_full (GMainContext *context,
4496 GSourceFunc function,
4498 GDestroyNotify notify)
4500 g_return_if_fail (function != NULL);
4503 context = g_main_context_default ();
4505 if (g_main_context_is_owner (context))
4507 while (function (data));
4514 GMainContext *thread_default;
4516 thread_default = g_main_context_get_thread_default ();
4518 if (!thread_default)
4519 thread_default = g_main_context_default ();
4521 if (thread_default == context && g_main_context_acquire (context))
4523 while (function (data));
4525 g_main_context_release (context);
4534 source = g_idle_source_new ();
4535 g_source_set_priority (source, priority);
4536 g_source_set_callback (source, function, data, notify);
4537 g_source_attach (source, context);
4538 g_source_unref (source);