1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
3 *
4 * gmain.c: Main loop abstraction, timeouts, and idle functions
5 * Copyright 1998 Owen Taylor
6 *
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.
11 *
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.
16 *
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.
21 */
22
23 /*
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/.
28 */
29
30 /*
31 * MT safe
32 */
33
34 #include "config.h"
35
36 /* Uncomment the next line (and the corresponding line in gpoll.c) to
37 * enable debugging printouts if the environment variable
38 * G_MAIN_POLL_DEBUG is set to some value.
39 */
40 /* #define G_MAIN_POLL_DEBUG */
41
42 #ifdef _WIN32
43 /* Always enable debugging printout on Windows, as it is more often
44 * needed there...
45 */
46 #define G_MAIN_POLL_DEBUG
47 #endif
48
49 #include "glib.h"
50 #include "gthreadprivate.h"
51 #include <signal.h>
52 #include <sys/types.h>
53 #include <time.h>
54 #include <stdlib.h>
55 #ifdef HAVE_SYS_TIME_H
56 #include <sys/time.h>
57 #endif /* HAVE_SYS_TIME_H */
58 #ifdef HAVE_UNISTD_H
59 #include <unistd.h>
60 #endif /* HAVE_UNISTD_H */
61 #include <errno.h>
62
63 #ifdef G_OS_WIN32
64 #define STRICT
65 #include <windows.h>
66 #endif /* G_OS_WIN32 */
67
68 #ifdef G_OS_BEOS
69 #include <sys/socket.h>
70 #include <sys/wait.h>
71 #endif /* G_OS_BEOS */
72
73 #ifdef G_OS_UNIX
74 #include <fcntl.h>
75 #include <sys/wait.h>
76 #endif
77
78 #include "galias.h"
79
80 /* Types */
81
82 typedef struct _GTimeoutSource GTimeoutSource;
83 typedef struct _GChildWatchSource GChildWatchSource;
84 typedef struct _GPollRec GPollRec;
85 typedef struct _GSourceCallback GSourceCallback;
86
87 typedef enum
88 {
89 G_SOURCE_READY = 1 << G_HOOK_FLAG_USER_SHIFT,
90 G_SOURCE_CAN_RECURSE = 1 << (G_HOOK_FLAG_USER_SHIFT + 1)
91 } GSourceFlags;
92
93 #ifdef G_THREADS_ENABLED
94 typedef struct _GMainWaiter GMainWaiter;
95
96 struct _GMainWaiter
97 {
98 GCond *cond;
99 GMutex *mutex;
100 };
101 #endif
102
103 typedef struct _GMainDispatch GMainDispatch;
104
105 struct _GMainDispatch
106 {
107 gint depth;
108 GSList *dispatching_sources; /* stack of current sources */
109 };
110
111 #ifdef G_MAIN_POLL_DEBUG
112 gboolean _g_main_poll_debug = FALSE;
113 #endif
114
115 struct _GMainContext
116 {
117 #ifdef G_THREADS_ENABLED
118 /* The following lock is used for both the list of sources
119 * and the list of poll records
120 */
121 GStaticMutex mutex;
122 GCond *cond;
123 GThread *owner;
124 guint owner_count;
125 GSList *waiters;
126 #endif
127
128 gint ref_count;
129
130 GPtrArray *pending_dispatches;
131 gint timeout; /* Timeout for current iteration */
132
133 guint next_id;
134 GSource *source_list;
135 gint in_check_or_prepare;
136
137 GPollRec *poll_records;
138 guint n_poll_records;
139 GPollFD *cached_poll_array;
140 guint cached_poll_array_size;
141
142 #ifdef G_THREADS_ENABLED
143 #ifndef G_OS_WIN32
144 /* this pipe is used to wake up the main loop when a source is added.
145 */
146 gint wake_up_pipe[2];
147 #else /* G_OS_WIN32 */
148 HANDLE wake_up_semaphore;
149 #endif /* G_OS_WIN32 */
150
151 GPollFD wake_up_rec;
152 gboolean poll_waiting;
153
154 /* Flag indicating whether the set of fd's changed during a poll */
155 gboolean poll_changed;
156 #endif /* G_THREADS_ENABLED */
157
158 GPollFunc poll_func;
159
160 GTimeVal current_time;
161 gboolean time_is_current;
162 };
163
164 struct _GSourceCallback
165 {
166 guint ref_count;
167 GSourceFunc func;
168 gpointer data;
169 GDestroyNotify notify;
170 };
171
172 struct _GMainLoop
173 {
174 GMainContext *context;
175 gboolean is_running;
176 gint ref_count;
177 };
178
179 struct _GTimeoutSource
180 {
181 GSource source;
182 GTimeVal expiration;
183 guint interval;
184 guint granularity;
185 };
186
187 struct _GChildWatchSource
188 {
189 GSource source;
190 GPid pid;
191 gint child_status;
192 #ifdef G_OS_WIN32
193 GPollFD poll;
194 #else /* G_OS_WIN32 */
195 gint count;
196 gboolean child_exited;
197 #endif /* G_OS_WIN32 */
198 };
199
200 struct _GPollRec
201 {
202 GPollFD *fd;
203 GPollRec *next;
204 gint priority;
205 };
206
207 #ifdef G_THREADS_ENABLED
208 #define LOCK_CONTEXT(context) g_static_mutex_lock (&context->mutex)
209 #define UNLOCK_CONTEXT(context) g_static_mutex_unlock (&context->mutex)
210 #define G_THREAD_SELF g_thread_self ()
211 #else
212 #define LOCK_CONTEXT(context) (void)0
213 #define UNLOCK_CONTEXT(context) (void)0
214 #define G_THREAD_SELF NULL
215 #endif
216
217 #define SOURCE_DESTROYED(source) (((source)->flags & G_HOOK_FLAG_ACTIVE) == 0)
218 #define SOURCE_BLOCKED(source) (((source)->flags & G_HOOK_FLAG_IN_CALL) != 0 && \
219 ((source)->flags & G_SOURCE_CAN_RECURSE) == 0)
220
221 #define SOURCE_UNREF(source, context) \
222 G_STMT_START { \
223 if ((source)->ref_count > 1) \
224 (source)->ref_count--; \
225 else \
226 g_source_unref_internal ((source), (context), TRUE); \
227 } G_STMT_END
228
229
230 /* Forward declarations */
231
232 static void g_source_unref_internal (GSource *source,
233 GMainContext *context,
234 gboolean have_lock);
235 static void g_source_destroy_internal (GSource *source,
236 GMainContext *context,
237 gboolean have_lock);
238 static void g_main_context_poll (GMainContext *context,
239 gint timeout,
240 gint priority,
241 GPollFD *fds,
242 gint n_fds);
243 static void g_main_context_add_poll_unlocked (GMainContext *context,
244 gint priority,
245 GPollFD *fd);
246 static void g_main_context_remove_poll_unlocked (GMainContext *context,
247 GPollFD *fd);
248 static void g_main_context_wakeup_unlocked (GMainContext *context);
249
250 static gboolean g_timeout_prepare (GSource *source,
251 gint *timeout);
252 static gboolean g_timeout_check (GSource *source);
253 static gboolean g_timeout_dispatch (GSource *source,
254 GSourceFunc callback,
255 gpointer user_data);
256 static gboolean g_child_watch_prepare (GSource *source,
257 gint *timeout);
258 static gboolean g_child_watch_check (GSource *source);
259 static gboolean g_child_watch_dispatch (GSource *source,
260 GSourceFunc callback,
261 gpointer user_data);
262 static gboolean g_idle_prepare (GSource *source,
263 gint *timeout);
264 static gboolean g_idle_check (GSource *source);
265 static gboolean g_idle_dispatch (GSource *source,
266 GSourceFunc callback,
267 gpointer user_data);
268
269 G_LOCK_DEFINE_STATIC (main_loop);
270 static GMainContext *default_main_context;
271 static GSList *main_contexts_without_pipe = NULL;
272
273 #ifndef G_OS_WIN32
274 /* Child status monitoring code */
275 enum {
276 CHILD_WATCH_UNINITIALIZED,
277 CHILD_WATCH_INITIALIZED_SINGLE,
278 CHILD_WATCH_INITIALIZED_THREADED
279 };
280 static gint child_watch_init_state = CHILD_WATCH_UNINITIALIZED;
281 static gint child_watch_count = 1;
282 static gint child_watch_wake_up_pipe[2] = {0, 0};
283 #endif /* !G_OS_WIN32 */
284 G_LOCK_DEFINE_STATIC (main_context_list);
285 static GSList *main_context_list = NULL;
286
287 static gint timer_perturb = -1;
288
289 GSourceFuncs g_timeout_funcs =
290 {
291 g_timeout_prepare,
292 g_timeout_check,
293 g_timeout_dispatch,
294 NULL
295 };
296
297 GSourceFuncs g_child_watch_funcs =
298 {
299 g_child_watch_prepare,
300 g_child_watch_check,
301 g_child_watch_dispatch,
302 NULL
303 };
304
305 GSourceFuncs g_idle_funcs =
306 {
307 g_idle_prepare,
308 g_idle_check,
309 g_idle_dispatch,
310 NULL
311 };
312
313 /**
314 * g_main_context_ref:
315 * @context: a #GMainContext
316 *
317 * Increases the reference count on a #GMainContext object by one.
318 *
319 * Returns: the @context that was passed in (since 2.6)
320 **/
321 GMainContext *
g_main_context_ref(GMainContext * context)322 g_main_context_ref (GMainContext *context)
323 {
324 g_return_val_if_fail (context != NULL, NULL);
325 g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL);
326
327 g_atomic_int_inc (&context->ref_count);
328
329 return context;
330 }
331
332 static inline void
poll_rec_list_free(GMainContext * context,GPollRec * list)333 poll_rec_list_free (GMainContext *context,
334 GPollRec *list)
335 {
336 g_slice_free_chain (GPollRec, list, next);
337 }
338
339 /**
340 * g_main_context_unref:
341 * @context: a #GMainContext
342 *
343 * Decreases the reference count on a #GMainContext object by one. If
344 * the result is zero, free the context and free all associated memory.
345 **/
346 void
g_main_context_unref(GMainContext * context)347 g_main_context_unref (GMainContext *context)
348 {
349 GSource *source;
350 g_return_if_fail (context != NULL);
351 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
352
353 if (!g_atomic_int_dec_and_test (&context->ref_count))
354 return;
355
356 G_LOCK (main_context_list);
357 main_context_list = g_slist_remove (main_context_list, context);
358 G_UNLOCK (main_context_list);
359
360 source = context->source_list;
361 while (source)
362 {
363 GSource *next = source->next;
364 g_source_destroy_internal (source, context, FALSE);
365 source = next;
366 }
367
368 #ifdef G_THREADS_ENABLED
369 g_static_mutex_free (&context->mutex);
370 #endif
371
372 g_ptr_array_free (context->pending_dispatches, TRUE);
373 g_free (context->cached_poll_array);
374
375 poll_rec_list_free (context, context->poll_records);
376
377 #ifdef G_THREADS_ENABLED
378 if (g_thread_supported())
379 {
380 #ifndef G_OS_WIN32
381 close (context->wake_up_pipe[0]);
382 close (context->wake_up_pipe[1]);
383 #else
384 CloseHandle (context->wake_up_semaphore);
385 #endif
386 }
387 else
388 main_contexts_without_pipe = g_slist_remove (main_contexts_without_pipe,
389 context);
390
391 if (context->cond != NULL)
392 g_cond_free (context->cond);
393 #endif
394
395 g_free (context);
396 }
397
398 #ifdef G_THREADS_ENABLED
399 static void
g_main_context_init_pipe(GMainContext * context)400 g_main_context_init_pipe (GMainContext *context)
401 {
402 # ifndef G_OS_WIN32
403 if (context->wake_up_pipe[0] != -1)
404 return;
405 if (pipe (context->wake_up_pipe) < 0)
406 g_error ("Cannot create pipe main loop wake-up: %s\n",
407 g_strerror (errno));
408
409 fcntl (context->wake_up_pipe[0], F_SETFD, FD_CLOEXEC);
410 fcntl (context->wake_up_pipe[1], F_SETFD, FD_CLOEXEC);
411
412 context->wake_up_rec.fd = context->wake_up_pipe[0];
413 context->wake_up_rec.events = G_IO_IN;
414 # else
415 if (context->wake_up_semaphore != NULL)
416 return;
417 context->wake_up_semaphore = CreateSemaphore (NULL, 0, 100, NULL);
418 if (context->wake_up_semaphore == NULL)
419 g_error ("Cannot create wake-up semaphore: %s",
420 g_win32_error_message (GetLastError ()));
421 context->wake_up_rec.fd = (gintptr) context->wake_up_semaphore;
422 context->wake_up_rec.events = G_IO_IN;
423
424 if (_g_main_poll_debug)
425 g_print ("wake-up semaphore: %p\n", context->wake_up_semaphore);
426 # endif
427 g_main_context_add_poll_unlocked (context, 0, &context->wake_up_rec);
428 }
429
430 void
_g_main_thread_init(void)431 _g_main_thread_init (void)
432 {
433 GSList *curr = main_contexts_without_pipe;
434 while (curr)
435 {
436 g_main_context_init_pipe ((GMainContext *)curr->data);
437 curr = curr->next;
438 }
439 g_slist_free (main_contexts_without_pipe);
440 main_contexts_without_pipe = NULL;
441 }
442 #endif /* G_THREADS_ENABLED */
443
444 /**
445 * g_main_context_new:
446 *
447 * Creates a new #GMainContext structure.
448 *
449 * Return value: the new #GMainContext
450 **/
451 GMainContext *
g_main_context_new(void)452 g_main_context_new (void)
453 {
454 GMainContext *context = g_new0 (GMainContext, 1);
455
456 #ifdef G_MAIN_POLL_DEBUG
457 {
458 static gboolean beenhere = FALSE;
459
460 if (!beenhere)
461 {
462 if (getenv ("G_MAIN_POLL_DEBUG") != NULL)
463 _g_main_poll_debug = TRUE;
464 beenhere = TRUE;
465 }
466 }
467 #endif
468
469 #ifdef G_THREADS_ENABLED
470 g_static_mutex_init (&context->mutex);
471
472 context->owner = NULL;
473 context->waiters = NULL;
474
475 # ifndef G_OS_WIN32
476 context->wake_up_pipe[0] = -1;
477 context->wake_up_pipe[1] = -1;
478 # else
479 context->wake_up_semaphore = NULL;
480 # endif
481 #endif
482
483 context->ref_count = 1;
484
485 context->next_id = 1;
486
487 context->source_list = NULL;
488
489 context->poll_func = g_poll;
490
491 context->cached_poll_array = NULL;
492 context->cached_poll_array_size = 0;
493
494 context->pending_dispatches = g_ptr_array_new ();
495
496 context->time_is_current = FALSE;
497
498 #ifdef G_THREADS_ENABLED
499 if (g_thread_supported ())
500 g_main_context_init_pipe (context);
501 else
502 main_contexts_without_pipe = g_slist_prepend (main_contexts_without_pipe,
503 context);
504 #endif
505
506 G_LOCK (main_context_list);
507 main_context_list = g_slist_append (main_context_list, context);
508
509 #ifdef G_MAIN_POLL_DEBUG
510 if (_g_main_poll_debug)
511 g_print ("created context=%p\n", context);
512 #endif
513
514 G_UNLOCK (main_context_list);
515
516 return context;
517 }
518
519 /**
520 * g_main_context_default:
521 *
522 * Returns the default main context. This is the main context used
523 * for main loop functions when a main loop is not explicitly
524 * specified.
525 *
526 * Return value: the default main context.
527 **/
528 GMainContext *
g_main_context_default(void)529 g_main_context_default (void)
530 {
531 /* Slow, but safe */
532
533 G_LOCK (main_loop);
534
535 if (!default_main_context)
536 {
537 default_main_context = g_main_context_new ();
538 #ifdef G_MAIN_POLL_DEBUG
539 if (_g_main_poll_debug)
540 g_print ("default context=%p\n", default_main_context);
541 #endif
542 }
543
544 G_UNLOCK (main_loop);
545
546 return default_main_context;
547 }
548
549 /* Hooks for adding to the main loop */
550
551 /**
552 * g_source_new:
553 * @source_funcs: structure containing functions that implement
554 * the sources behavior.
555 * @struct_size: size of the #GSource structure to create.
556 *
557 * Creates a new #GSource structure. The size is specified to
558 * allow creating structures derived from #GSource that contain
559 * additional data. The size passed in must be at least
560 * <literal>sizeof (GSource)</literal>.
561 *
562 * The source will not initially be associated with any #GMainContext
563 * and must be added to one with g_source_attach() before it will be
564 * executed.
565 *
566 * Return value: the newly-created #GSource.
567 **/
568 GSource *
g_source_new(GSourceFuncs * source_funcs,guint struct_size)569 g_source_new (GSourceFuncs *source_funcs,
570 guint struct_size)
571 {
572 GSource *source;
573
574 g_return_val_if_fail (source_funcs != NULL, NULL);
575 g_return_val_if_fail (struct_size >= sizeof (GSource), NULL);
576
577 source = (GSource*) g_malloc0 (struct_size);
578
579 source->source_funcs = source_funcs;
580 source->ref_count = 1;
581
582 source->priority = G_PRIORITY_DEFAULT;
583
584 source->flags = G_HOOK_FLAG_ACTIVE;
585
586 /* NULL/0 initialization for all other fields */
587
588 return source;
589 }
590
591 /* Holds context's lock
592 */
593 static void
g_source_list_add(GSource * source,GMainContext * context)594 g_source_list_add (GSource *source,
595 GMainContext *context)
596 {
597 GSource *tmp_source, *last_source;
598
599 last_source = NULL;
600 tmp_source = context->source_list;
601 while (tmp_source && tmp_source->priority <= source->priority)
602 {
603 last_source = tmp_source;
604 tmp_source = tmp_source->next;
605 }
606
607 source->next = tmp_source;
608 if (tmp_source)
609 tmp_source->prev = source;
610
611 source->prev = last_source;
612 if (last_source)
613 last_source->next = source;
614 else
615 context->source_list = source;
616 }
617
618 /* Holds context's lock
619 */
620 static void
g_source_list_remove(GSource * source,GMainContext * context)621 g_source_list_remove (GSource *source,
622 GMainContext *context)
623 {
624 if (source->prev)
625 source->prev->next = source->next;
626 else
627 context->source_list = source->next;
628
629 if (source->next)
630 source->next->prev = source->prev;
631
632 source->prev = NULL;
633 source->next = NULL;
634 }
635
636 /**
637 * g_source_attach:
638 * @source: a #GSource
639 * @context: a #GMainContext (if %NULL, the default context will be used)
640 *
641 * Adds a #GSource to a @context so that it will be executed within
642 * that context. Remove it by calling g_source_destroy().
643 *
644 * Return value: the ID (greater than 0) for the source within the
645 * #GMainContext.
646 **/
647 guint
g_source_attach(GSource * source,GMainContext * context)648 g_source_attach (GSource *source,
649 GMainContext *context)
650 {
651 guint result = 0;
652 GSList *tmp_list;
653
654 g_return_val_if_fail (source->context == NULL, 0);
655 g_return_val_if_fail (!SOURCE_DESTROYED (source), 0);
656
657 if (!context)
658 context = g_main_context_default ();
659
660 LOCK_CONTEXT (context);
661
662 source->context = context;
663 result = source->source_id = context->next_id++;
664
665 source->ref_count++;
666 g_source_list_add (source, context);
667
668 tmp_list = source->poll_fds;
669 while (tmp_list)
670 {
671 g_main_context_add_poll_unlocked (context, source->priority, tmp_list->data);
672 tmp_list = tmp_list->next;
673 }
674
675 #ifdef G_THREADS_ENABLED
676 /* Now wake up the main loop if it is waiting in the poll() */
677 g_main_context_wakeup_unlocked (context);
678 #endif
679
680 UNLOCK_CONTEXT (context);
681
682 return result;
683 }
684
685 static void
g_source_destroy_internal(GSource * source,GMainContext * context,gboolean have_lock)686 g_source_destroy_internal (GSource *source,
687 GMainContext *context,
688 gboolean have_lock)
689 {
690 if (!have_lock)
691 LOCK_CONTEXT (context);
692
693 if (!SOURCE_DESTROYED (source))
694 {
695 GSList *tmp_list;
696 gpointer old_cb_data;
697 GSourceCallbackFuncs *old_cb_funcs;
698
699 source->flags &= ~G_HOOK_FLAG_ACTIVE;
700
701 old_cb_data = source->callback_data;
702 old_cb_funcs = source->callback_funcs;
703
704 source->callback_data = NULL;
705 source->callback_funcs = NULL;
706
707 if (old_cb_funcs)
708 {
709 UNLOCK_CONTEXT (context);
710 old_cb_funcs->unref (old_cb_data);
711 LOCK_CONTEXT (context);
712 }
713
714 if (!SOURCE_BLOCKED (source))
715 {
716 tmp_list = source->poll_fds;
717 while (tmp_list)
718 {
719 g_main_context_remove_poll_unlocked (context, tmp_list->data);
720 tmp_list = tmp_list->next;
721 }
722 }
723
724 g_source_unref_internal (source, context, TRUE);
725 }
726
727 if (!have_lock)
728 UNLOCK_CONTEXT (context);
729 }
730
731 /**
732 * g_source_destroy:
733 * @source: a #GSource
734 *
735 * Removes a source from its #GMainContext, if any, and mark it as
736 * destroyed. The source cannot be subsequently added to another
737 * context.
738 **/
739 void
g_source_destroy(GSource * source)740 g_source_destroy (GSource *source)
741 {
742 GMainContext *context;
743
744 g_return_if_fail (source != NULL);
745
746 context = source->context;
747
748 if (context)
749 g_source_destroy_internal (source, context, FALSE);
750 else
751 source->flags &= ~G_HOOK_FLAG_ACTIVE;
752 }
753
754 /**
755 * g_source_get_id:
756 * @source: a #GSource
757 *
758 * Returns the numeric ID for a particular source. The ID of a source
759 * is a positive integer which is unique within a particular main loop
760 * context. The reverse
761 * mapping from ID to source is done by g_main_context_find_source_by_id().
762 *
763 * Return value: the ID (greater than 0) for the source
764 **/
765 guint
g_source_get_id(GSource * source)766 g_source_get_id (GSource *source)
767 {
768 guint result;
769
770 g_return_val_if_fail (source != NULL, 0);
771 g_return_val_if_fail (source->context != NULL, 0);
772
773 LOCK_CONTEXT (source->context);
774 result = source->source_id;
775 UNLOCK_CONTEXT (source->context);
776
777 return result;
778 }
779
780 /**
781 * g_source_get_context:
782 * @source: a #GSource
783 *
784 * Gets the #GMainContext with which the source is associated.
785 * Calling this function on a destroyed source is an error.
786 *
787 * Return value: the #GMainContext with which the source is associated,
788 * or %NULL if the context has not yet been added
789 * to a source.
790 **/
791 GMainContext *
g_source_get_context(GSource * source)792 g_source_get_context (GSource *source)
793 {
794 g_return_val_if_fail (!SOURCE_DESTROYED (source), NULL);
795
796 return source->context;
797 }
798
799 /**
800 * g_source_add_poll:
801 * @source:a #GSource
802 * @fd: a #GPollFD structure holding information about a file
803 * descriptor to watch.
804 *
805 * Adds a file descriptor to the set of file descriptors polled for
806 * this source. This is usually combined with g_source_new() to add an
807 * event source. The event source's check function will typically test
808 * the @revents field in the #GPollFD struct and return %TRUE if events need
809 * to be processed.
810 **/
811 void
g_source_add_poll(GSource * source,GPollFD * fd)812 g_source_add_poll (GSource *source,
813 GPollFD *fd)
814 {
815 GMainContext *context;
816
817 g_return_if_fail (source != NULL);
818 g_return_if_fail (fd != NULL);
819 g_return_if_fail (!SOURCE_DESTROYED (source));
820
821 context = source->context;
822
823 if (context)
824 LOCK_CONTEXT (context);
825
826 source->poll_fds = g_slist_prepend (source->poll_fds, fd);
827
828 if (context)
829 {
830 if (!SOURCE_BLOCKED (source))
831 g_main_context_add_poll_unlocked (context, source->priority, fd);
832 UNLOCK_CONTEXT (context);
833 }
834 }
835
836 /**
837 * g_source_remove_poll:
838 * @source:a #GSource
839 * @fd: a #GPollFD structure previously passed to g_source_add_poll().
840 *
841 * Removes a file descriptor from the set of file descriptors polled for
842 * this source.
843 **/
844 void
g_source_remove_poll(GSource * source,GPollFD * fd)845 g_source_remove_poll (GSource *source,
846 GPollFD *fd)
847 {
848 GMainContext *context;
849
850 g_return_if_fail (source != NULL);
851 g_return_if_fail (fd != NULL);
852 g_return_if_fail (!SOURCE_DESTROYED (source));
853
854 context = source->context;
855
856 if (context)
857 LOCK_CONTEXT (context);
858
859 source->poll_fds = g_slist_remove (source->poll_fds, fd);
860
861 if (context)
862 {
863 if (!SOURCE_BLOCKED (source))
864 g_main_context_remove_poll_unlocked (context, fd);
865 UNLOCK_CONTEXT (context);
866 }
867 }
868
869 /**
870 * g_source_set_callback_indirect:
871 * @source: the source
872 * @callback_data: pointer to callback data "object"
873 * @callback_funcs: functions for reference counting @callback_data
874 * and getting the callback and data
875 *
876 * Sets the callback function storing the data as a refcounted callback
877 * "object". This is used internally. Note that calling
878 * g_source_set_callback_indirect() assumes
879 * an initial reference count on @callback_data, and thus
880 * @callback_funcs->unref will eventually be called once more
881 * than @callback_funcs->ref.
882 **/
883 void
g_source_set_callback_indirect(GSource * source,gpointer callback_data,GSourceCallbackFuncs * callback_funcs)884 g_source_set_callback_indirect (GSource *source,
885 gpointer callback_data,
886 GSourceCallbackFuncs *callback_funcs)
887 {
888 GMainContext *context;
889 gpointer old_cb_data;
890 GSourceCallbackFuncs *old_cb_funcs;
891
892 g_return_if_fail (source != NULL);
893 g_return_if_fail (callback_funcs != NULL || callback_data == NULL);
894
895 context = source->context;
896
897 if (context)
898 LOCK_CONTEXT (context);
899
900 old_cb_data = source->callback_data;
901 old_cb_funcs = source->callback_funcs;
902
903 source->callback_data = callback_data;
904 source->callback_funcs = callback_funcs;
905
906 if (context)
907 UNLOCK_CONTEXT (context);
908
909 if (old_cb_funcs)
910 old_cb_funcs->unref (old_cb_data);
911 }
912
913 static void
g_source_callback_ref(gpointer cb_data)914 g_source_callback_ref (gpointer cb_data)
915 {
916 GSourceCallback *callback = cb_data;
917
918 callback->ref_count++;
919 }
920
921
922 static void
g_source_callback_unref(gpointer cb_data)923 g_source_callback_unref (gpointer cb_data)
924 {
925 GSourceCallback *callback = cb_data;
926
927 callback->ref_count--;
928 if (callback->ref_count == 0)
929 {
930 if (callback->notify)
931 callback->notify (callback->data);
932 g_free (callback);
933 }
934 }
935
936 static void
g_source_callback_get(gpointer cb_data,GSource * source,GSourceFunc * func,gpointer * data)937 g_source_callback_get (gpointer cb_data,
938 GSource *source,
939 GSourceFunc *func,
940 gpointer *data)
941 {
942 GSourceCallback *callback = cb_data;
943
944 *func = callback->func;
945 *data = callback->data;
946 }
947
948 static GSourceCallbackFuncs g_source_callback_funcs = {
949 g_source_callback_ref,
950 g_source_callback_unref,
951 g_source_callback_get,
952 };
953
954 /**
955 * g_source_set_callback:
956 * @source: the source
957 * @func: a callback function
958 * @data: the data to pass to callback function
959 * @notify: a function to call when @data is no longer in use, or %NULL.
960 *
961 * Sets the callback function for a source. The callback for a source is
962 * called from the source's dispatch function.
963 *
964 * The exact type of @func depends on the type of source; ie. you
965 * should not count on @func being called with @data as its first
966 * parameter.
967 *
968 * Typically, you won't use this function. Instead use functions specific
969 * to the type of source you are using.
970 **/
971 void
g_source_set_callback(GSource * source,GSourceFunc func,gpointer data,GDestroyNotify notify)972 g_source_set_callback (GSource *source,
973 GSourceFunc func,
974 gpointer data,
975 GDestroyNotify notify)
976 {
977 GSourceCallback *new_callback;
978
979 g_return_if_fail (source != NULL);
980
981 new_callback = g_new (GSourceCallback, 1);
982
983 new_callback->ref_count = 1;
984 new_callback->func = func;
985 new_callback->data = data;
986 new_callback->notify = notify;
987
988 g_source_set_callback_indirect (source, new_callback, &g_source_callback_funcs);
989 }
990
991
992 /**
993 * g_source_set_funcs:
994 * @source: a #GSource
995 * @funcs: the new #GSourceFuncs
996 *
997 * Sets the source functions (can be used to override
998 * default implementations) of an unattached source.
999 *
1000 * Since: 2.12
1001 */
1002 void
g_source_set_funcs(GSource * source,GSourceFuncs * funcs)1003 g_source_set_funcs (GSource *source,
1004 GSourceFuncs *funcs)
1005 {
1006 g_return_if_fail (source != NULL);
1007 g_return_if_fail (source->context == NULL);
1008 g_return_if_fail (source->ref_count > 0);
1009 g_return_if_fail (funcs != NULL);
1010
1011 source->source_funcs = funcs;
1012 }
1013
1014 /**
1015 * g_source_set_priority:
1016 * @source: a #GSource
1017 * @priority: the new priority.
1018 *
1019 * Sets the priority of a source. While the main loop is being
1020 * run, a source will be dispatched if it is ready to be dispatched and no sources
1021 * at a higher (numerically smaller) priority are ready to be dispatched.
1022 **/
1023 void
g_source_set_priority(GSource * source,gint priority)1024 g_source_set_priority (GSource *source,
1025 gint priority)
1026 {
1027 GSList *tmp_list;
1028 GMainContext *context;
1029
1030 g_return_if_fail (source != NULL);
1031
1032 context = source->context;
1033
1034 if (context)
1035 LOCK_CONTEXT (context);
1036
1037 source->priority = priority;
1038
1039 if (context)
1040 {
1041 /* Remove the source from the context's source and then
1042 * add it back so it is sorted in the correct plcae
1043 */
1044 g_source_list_remove (source, source->context);
1045 g_source_list_add (source, source->context);
1046
1047 if (!SOURCE_BLOCKED (source))
1048 {
1049 tmp_list = source->poll_fds;
1050 while (tmp_list)
1051 {
1052 g_main_context_remove_poll_unlocked (context, tmp_list->data);
1053 g_main_context_add_poll_unlocked (context, priority, tmp_list->data);
1054
1055 tmp_list = tmp_list->next;
1056 }
1057 }
1058
1059 UNLOCK_CONTEXT (source->context);
1060 }
1061 }
1062
1063 /**
1064 * g_source_get_priority:
1065 * @source: a #GSource
1066 *
1067 * Gets the priority of a source.
1068 *
1069 * Return value: the priority of the source
1070 **/
1071 gint
g_source_get_priority(GSource * source)1072 g_source_get_priority (GSource *source)
1073 {
1074 g_return_val_if_fail (source != NULL, 0);
1075
1076 return source->priority;
1077 }
1078
1079 /**
1080 * g_source_set_can_recurse:
1081 * @source: a #GSource
1082 * @can_recurse: whether recursion is allowed for this source
1083 *
1084 * Sets whether a source can be called recursively. If @can_recurse is
1085 * %TRUE, then while the source is being dispatched then this source
1086 * will be processed normally. Otherwise, all processing of this
1087 * source is blocked until the dispatch function returns.
1088 **/
1089 void
g_source_set_can_recurse(GSource * source,gboolean can_recurse)1090 g_source_set_can_recurse (GSource *source,
1091 gboolean can_recurse)
1092 {
1093 GMainContext *context;
1094
1095 g_return_if_fail (source != NULL);
1096
1097 context = source->context;
1098
1099 if (context)
1100 LOCK_CONTEXT (context);
1101
1102 if (can_recurse)
1103 source->flags |= G_SOURCE_CAN_RECURSE;
1104 else
1105 source->flags &= ~G_SOURCE_CAN_RECURSE;
1106
1107 if (context)
1108 UNLOCK_CONTEXT (context);
1109 }
1110
1111 /**
1112 * g_source_get_can_recurse:
1113 * @source: a #GSource
1114 *
1115 * Checks whether a source is allowed to be called recursively.
1116 * see g_source_set_can_recurse().
1117 *
1118 * Return value: whether recursion is allowed.
1119 **/
1120 gboolean
g_source_get_can_recurse(GSource * source)1121 g_source_get_can_recurse (GSource *source)
1122 {
1123 g_return_val_if_fail (source != NULL, FALSE);
1124
1125 return (source->flags & G_SOURCE_CAN_RECURSE) != 0;
1126 }
1127
1128 /**
1129 * g_source_ref:
1130 * @source: a #GSource
1131 *
1132 * Increases the reference count on a source by one.
1133 *
1134 * Return value: @source
1135 **/
1136 GSource *
g_source_ref(GSource * source)1137 g_source_ref (GSource *source)
1138 {
1139 GMainContext *context;
1140
1141 g_return_val_if_fail (source != NULL, NULL);
1142
1143 context = source->context;
1144
1145 if (context)
1146 LOCK_CONTEXT (context);
1147
1148 source->ref_count++;
1149
1150 if (context)
1151 UNLOCK_CONTEXT (context);
1152
1153 return source;
1154 }
1155
1156 /* g_source_unref() but possible to call within context lock
1157 */
1158 static void
g_source_unref_internal(GSource * source,GMainContext * context,gboolean have_lock)1159 g_source_unref_internal (GSource *source,
1160 GMainContext *context,
1161 gboolean have_lock)
1162 {
1163 gpointer old_cb_data = NULL;
1164 GSourceCallbackFuncs *old_cb_funcs = NULL;
1165
1166 g_return_if_fail (source != NULL);
1167
1168 if (!have_lock && context)
1169 LOCK_CONTEXT (context);
1170
1171 source->ref_count--;
1172 if (source->ref_count == 0)
1173 {
1174 old_cb_data = source->callback_data;
1175 old_cb_funcs = source->callback_funcs;
1176
1177 source->callback_data = NULL;
1178 source->callback_funcs = NULL;
1179
1180 if (context && !SOURCE_DESTROYED (source))
1181 {
1182 g_warning (G_STRLOC ": ref_count == 0, but source is still attached to a context!");
1183 source->ref_count++;
1184 }
1185 else if (context)
1186 g_source_list_remove (source, context);
1187
1188 if (source->source_funcs->finalize)
1189 source->source_funcs->finalize (source);
1190
1191 g_slist_free (source->poll_fds);
1192 source->poll_fds = NULL;
1193 g_free (source);
1194 }
1195
1196 if (!have_lock && context)
1197 UNLOCK_CONTEXT (context);
1198
1199 if (old_cb_funcs)
1200 {
1201 if (have_lock)
1202 UNLOCK_CONTEXT (context);
1203
1204 old_cb_funcs->unref (old_cb_data);
1205
1206 if (have_lock)
1207 LOCK_CONTEXT (context);
1208 }
1209 }
1210
1211 /**
1212 * g_source_unref:
1213 * @source: a #GSource
1214 *
1215 * Decreases the reference count of a source by one. If the
1216 * resulting reference count is zero the source and associated
1217 * memory will be destroyed.
1218 **/
1219 void
g_source_unref(GSource * source)1220 g_source_unref (GSource *source)
1221 {
1222 g_return_if_fail (source != NULL);
1223
1224 g_source_unref_internal (source, source->context, FALSE);
1225 }
1226
1227 /**
1228 * g_main_context_find_source_by_id:
1229 * @context: a #GMainContext (if %NULL, the default context will be used)
1230 * @source_id: the source ID, as returned by g_source_get_id().
1231 *
1232 * Finds a #GSource given a pair of context and ID.
1233 *
1234 * Return value: the #GSource if found, otherwise, %NULL
1235 **/
1236 GSource *
g_main_context_find_source_by_id(GMainContext * context,guint source_id)1237 g_main_context_find_source_by_id (GMainContext *context,
1238 guint source_id)
1239 {
1240 GSource *source;
1241
1242 g_return_val_if_fail (source_id > 0, NULL);
1243
1244 if (context == NULL)
1245 context = g_main_context_default ();
1246
1247 LOCK_CONTEXT (context);
1248
1249 source = context->source_list;
1250 while (source)
1251 {
1252 if (!SOURCE_DESTROYED (source) &&
1253 source->source_id == source_id)
1254 break;
1255 source = source->next;
1256 }
1257
1258 UNLOCK_CONTEXT (context);
1259
1260 return source;
1261 }
1262
1263 /**
1264 * g_main_context_find_source_by_funcs_user_data:
1265 * @context: a #GMainContext (if %NULL, the default context will be used).
1266 * @funcs: the @source_funcs passed to g_source_new().
1267 * @user_data: the user data from the callback.
1268 *
1269 * Finds a source with the given source functions and user data. If
1270 * multiple sources exist with the same source function and user data,
1271 * the first one found will be returned.
1272 *
1273 * Return value: the source, if one was found, otherwise %NULL
1274 **/
1275 GSource *
g_main_context_find_source_by_funcs_user_data(GMainContext * context,GSourceFuncs * funcs,gpointer user_data)1276 g_main_context_find_source_by_funcs_user_data (GMainContext *context,
1277 GSourceFuncs *funcs,
1278 gpointer user_data)
1279 {
1280 GSource *source;
1281
1282 g_return_val_if_fail (funcs != NULL, NULL);
1283
1284 if (context == NULL)
1285 context = g_main_context_default ();
1286
1287 LOCK_CONTEXT (context);
1288
1289 source = context->source_list;
1290 while (source)
1291 {
1292 if (!SOURCE_DESTROYED (source) &&
1293 source->source_funcs == funcs &&
1294 source->callback_funcs)
1295 {
1296 GSourceFunc callback;
1297 gpointer callback_data;
1298
1299 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
1300
1301 if (callback_data == user_data)
1302 break;
1303 }
1304 source = source->next;
1305 }
1306
1307 UNLOCK_CONTEXT (context);
1308
1309 return source;
1310 }
1311
1312 /**
1313 * g_main_context_find_source_by_user_data:
1314 * @context: a #GMainContext
1315 * @user_data: the user_data for the callback.
1316 *
1317 * Finds a source with the given user data for the callback. If
1318 * multiple sources exist with the same user data, the first
1319 * one found will be returned.
1320 *
1321 * Return value: the source, if one was found, otherwise %NULL
1322 **/
1323 GSource *
g_main_context_find_source_by_user_data(GMainContext * context,gpointer user_data)1324 g_main_context_find_source_by_user_data (GMainContext *context,
1325 gpointer user_data)
1326 {
1327 GSource *source;
1328
1329 if (context == NULL)
1330 context = g_main_context_default ();
1331
1332 LOCK_CONTEXT (context);
1333
1334 source = context->source_list;
1335 while (source)
1336 {
1337 if (!SOURCE_DESTROYED (source) &&
1338 source->callback_funcs)
1339 {
1340 GSourceFunc callback;
1341 gpointer callback_data = NULL;
1342
1343 source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
1344
1345 if (callback_data == user_data)
1346 break;
1347 }
1348 source = source->next;
1349 }
1350
1351 UNLOCK_CONTEXT (context);
1352
1353 return source;
1354 }
1355
1356 /**
1357 * g_source_remove:
1358 * @tag: the ID of the source to remove.
1359 *
1360 * Removes the source with the given id from the default main context.
1361 * The id of
1362 * a #GSource is given by g_source_get_id(), or will be returned by the
1363 * functions g_source_attach(), g_idle_add(), g_idle_add_full(),
1364 * g_timeout_add(), g_timeout_add_full(), g_child_watch_add(),
1365 * g_child_watch_add_full(), g_io_add_watch(), and g_io_add_watch_full().
1366 *
1367 * See also g_source_destroy(). You must use g_source_destroy() for sources
1368 * added to a non-default main context.
1369 *
1370 * Return value: %TRUE if the source was found and removed.
1371 **/
1372 gboolean
g_source_remove(guint tag)1373 g_source_remove (guint tag)
1374 {
1375 GSource *source;
1376
1377 g_return_val_if_fail (tag > 0, FALSE);
1378
1379 source = g_main_context_find_source_by_id (NULL, tag);
1380 if (source)
1381 g_source_destroy (source);
1382
1383 return source != NULL;
1384 }
1385
1386 /**
1387 * g_source_remove_by_user_data:
1388 * @user_data: the user_data for the callback.
1389 *
1390 * Removes a source from the default main loop context given the user
1391 * data for the callback. If multiple sources exist with the same user
1392 * data, only one will be destroyed.
1393 *
1394 * Return value: %TRUE if a source was found and removed.
1395 **/
1396 gboolean
g_source_remove_by_user_data(gpointer user_data)1397 g_source_remove_by_user_data (gpointer user_data)
1398 {
1399 GSource *source;
1400
1401 source = g_main_context_find_source_by_user_data (NULL, user_data);
1402 if (source)
1403 {
1404 g_source_destroy (source);
1405 return TRUE;
1406 }
1407 else
1408 return FALSE;
1409 }
1410
1411 /**
1412 * g_source_remove_by_funcs_user_data:
1413 * @funcs: The @source_funcs passed to g_source_new()
1414 * @user_data: the user data for the callback
1415 *
1416 * Removes a source from the default main loop context given the
1417 * source functions and user data. If multiple sources exist with the
1418 * same source functions and user data, only one will be destroyed.
1419 *
1420 * Return value: %TRUE if a source was found and removed.
1421 **/
1422 gboolean
g_source_remove_by_funcs_user_data(GSourceFuncs * funcs,gpointer user_data)1423 g_source_remove_by_funcs_user_data (GSourceFuncs *funcs,
1424 gpointer user_data)
1425 {
1426 GSource *source;
1427
1428 g_return_val_if_fail (funcs != NULL, FALSE);
1429
1430 source = g_main_context_find_source_by_funcs_user_data (NULL, funcs, user_data);
1431 if (source)
1432 {
1433 g_source_destroy (source);
1434 return TRUE;
1435 }
1436 else
1437 return FALSE;
1438 }
1439
1440 /**
1441 * g_get_current_time:
1442 * @result: #GTimeVal structure in which to store current time.
1443 *
1444 * Equivalent to the UNIX gettimeofday() function, but portable.
1445 **/
1446 void
g_get_current_time(GTimeVal * result)1447 g_get_current_time (GTimeVal *result)
1448 {
1449 #ifndef G_OS_WIN32
1450 struct timeval r;
1451
1452 g_return_if_fail (result != NULL);
1453
1454 /*this is required on alpha, there the timeval structs are int's
1455 not longs and a cast only would fail horribly*/
1456 gettimeofday (&r, NULL);
1457 result->tv_sec = r.tv_sec;
1458 result->tv_usec = r.tv_usec;
1459 #else
1460 FILETIME ft;
1461 guint64 time64;
1462
1463 g_return_if_fail (result != NULL);
1464
1465 GetSystemTimeAsFileTime (&ft);
1466 memmove (&time64, &ft, sizeof (FILETIME));
1467
1468 /* Convert from 100s of nanoseconds since 1601-01-01
1469 * to Unix epoch. Yes, this is Y2038 unsafe.
1470 */
1471 time64 -= G_GINT64_CONSTANT (116444736000000000);
1472 time64 /= 10;
1473
1474 result->tv_sec = time64 / 1000000;
1475 result->tv_usec = time64 % 1000000;
1476 #endif
1477 }
1478
1479 static void
g_main_dispatch_free(gpointer dispatch)1480 g_main_dispatch_free (gpointer dispatch)
1481 {
1482 g_slice_free (GMainDispatch, dispatch);
1483 }
1484
1485 /* Running the main loop */
1486
1487 static GMainDispatch *
get_dispatch(void)1488 get_dispatch (void)
1489 {
1490 static GStaticPrivate depth_private = G_STATIC_PRIVATE_INIT;
1491 GMainDispatch *dispatch = g_static_private_get (&depth_private);
1492 if (!dispatch)
1493 {
1494 dispatch = g_slice_new0 (GMainDispatch);
1495 g_static_private_set (&depth_private, dispatch, g_main_dispatch_free);
1496 }
1497
1498 return dispatch;
1499 }
1500
1501 /**
1502 * g_main_depth:
1503 *
1504 * Returns the depth of the stack of calls to
1505 * g_main_context_dispatch() on any #GMainContext in the current thread.
1506 * That is, when called from the toplevel, it gives 0. When
1507 * called from within a callback from g_main_context_iteration()
1508 * (or g_main_loop_run(), etc.) it returns 1. When called from within
1509 * a callback to a recursive call to g_main_context_iterate(),
1510 * it returns 2. And so forth.
1511 *
1512 * This function is useful in a situation like the following:
1513 * Imagine an extremely simple "garbage collected" system.
1514 *
1515 * |[
1516 * static GList *free_list;
1517 *
1518 * gpointer
1519 * allocate_memory (gsize size)
1520 * {
1521 * gpointer result = g_malloc (size);
1522 * free_list = g_list_prepend (free_list, result);
1523 * return result;
1524 * }
1525 *
1526 * void
1527 * free_allocated_memory (void)
1528 * {
1529 * GList *l;
1530 * for (l = free_list; l; l = l->next);
1531 * g_free (l->data);
1532 * g_list_free (free_list);
1533 * free_list = NULL;
1534 * }
1535 *
1536 * [...]
1537 *
1538 * while (TRUE);
1539 * {
1540 * g_main_context_iteration (NULL, TRUE);
1541 * free_allocated_memory();
1542 * }
1543 * ]|
1544 *
1545 * This works from an application, however, if you want to do the same
1546 * thing from a library, it gets more difficult, since you no longer
1547 * control the main loop. You might think you can simply use an idle
1548 * function to make the call to free_allocated_memory(), but that
1549 * doesn't work, since the idle function could be called from a
1550 * recursive callback. This can be fixed by using g_main_depth()
1551 *
1552 * |[
1553 * gpointer
1554 * allocate_memory (gsize size)
1555 * {
1556 * FreeListBlock *block = g_new (FreeListBlock, 1);
1557 * block->mem = g_malloc (size);
1558 * block->depth = g_main_depth ();
1559 * free_list = g_list_prepend (free_list, block);
1560 * return block->mem;
1561 * }
1562 *
1563 * void
1564 * free_allocated_memory (void)
1565 * {
1566 * GList *l;
1567 *
1568 * int depth = g_main_depth ();
1569 * for (l = free_list; l; );
1570 * {
1571 * GList *next = l->next;
1572 * FreeListBlock *block = l->data;
1573 * if (block->depth > depth)
1574 * {
1575 * g_free (block->mem);
1576 * g_free (block);
1577 * free_list = g_list_delete_link (free_list, l);
1578 * }
1579 *
1580 * l = next;
1581 * }
1582 * }
1583 * ]|
1584 *
1585 * There is a temptation to use g_main_depth() to solve
1586 * problems with reentrancy. For instance, while waiting for data
1587 * to be received from the network in response to a menu item,
1588 * the menu item might be selected again. It might seem that
1589 * one could make the menu item's callback return immediately
1590 * and do nothing if g_main_depth() returns a value greater than 1.
1591 * However, this should be avoided since the user then sees selecting
1592 * the menu item do nothing. Furthermore, you'll find yourself adding
1593 * these checks all over your code, since there are doubtless many,
1594 * many things that the user could do. Instead, you can use the
1595 * following techniques:
1596 *
1597 * <orderedlist>
1598 * <listitem>
1599 * <para>
1600 * Use gtk_widget_set_sensitive() or modal dialogs to prevent
1601 * the user from interacting with elements while the main
1602 * loop is recursing.
1603 * </para>
1604 * </listitem>
1605 * <listitem>
1606 * <para>
1607 * Avoid main loop recursion in situations where you can't handle
1608 * arbitrary callbacks. Instead, structure your code so that you
1609 * simply return to the main loop and then get called again when
1610 * there is more work to do.
1611 * </para>
1612 * </listitem>
1613 * </orderedlist>
1614 *
1615 * Return value: The main loop recursion level in the current thread
1616 **/
1617 int
g_main_depth(void)1618 g_main_depth (void)
1619 {
1620 GMainDispatch *dispatch = get_dispatch ();
1621 return dispatch->depth;
1622 }
1623
1624 /**
1625 * g_main_current_source:
1626 *
1627 * Returns the currently firing source for this thread.
1628 *
1629 * Return value: The currently firing source or %NULL.
1630 *
1631 * Since: 2.12
1632 */
1633 GSource *
g_main_current_source(void)1634 g_main_current_source (void)
1635 {
1636 GMainDispatch *dispatch = get_dispatch ();
1637 return dispatch->dispatching_sources ? dispatch->dispatching_sources->data : NULL;
1638 }
1639
1640 /**
1641 * g_source_is_destroyed:
1642 * @source: a #GSource
1643 *
1644 * Returns whether @source has been destroyed.
1645 *
1646 * This is important when you operate upon your objects
1647 * from within idle handlers, but may have freed the object
1648 * before the dispatch of your idle handler.
1649 *
1650 * |[
1651 * static gboolean
1652 * idle_callback (gpointer data)
1653 * {
1654 * SomeWidget *self = data;
1655 *
1656 * GDK_THREADS_ENTER (<!-- -->);
1657 * /<!-- -->* do stuff with self *<!-- -->/
1658 * self->idle_id = 0;
1659 * GDK_THREADS_LEAVE (<!-- -->);
1660 *
1661 * return FALSE;
1662 * }
1663 *
1664 * static void
1665 * some_widget_do_stuff_later (SomeWidget *self)
1666 * {
1667 * self->idle_id = g_idle_add (idle_callback, self);
1668 * }
1669 *
1670 * static void
1671 * some_widget_finalize (GObject *object)
1672 * {
1673 * SomeWidget *self = SOME_WIDGET (object);
1674 *
1675 * if (self->idle_id)
1676 * g_source_remove (self->idle_id);
1677 *
1678 * G_OBJECT_CLASS (parent_class)->finalize (object);
1679 * }
1680 * ]|
1681 *
1682 * This will fail in a multi-threaded application if the
1683 * widget is destroyed before the idle handler fires due
1684 * to the use after free in the callback. A solution, to
1685 * this particular problem, is to check to if the source
1686 * has already been destroy within the callback.
1687 *
1688 * |[
1689 * static gboolean
1690 * idle_callback (gpointer data)
1691 * {
1692 * SomeWidget *self = data;
1693 *
1694 * GDK_THREADS_ENTER ();
1695 * if (!g_source_is_destroyed (g_main_current_source ()))
1696 * {
1697 * /<!-- -->* do stuff with self *<!-- -->/
1698 * }
1699 * GDK_THREADS_LEAVE ();
1700 *
1701 * return FALSE;
1702 * }
1703 * ]|
1704 *
1705 * Return value: %TRUE if the source has been destroyed
1706 *
1707 * Since: 2.12
1708 */
1709 gboolean
g_source_is_destroyed(GSource * source)1710 g_source_is_destroyed (GSource *source)
1711 {
1712 return SOURCE_DESTROYED (source);
1713 }
1714
1715
1716 /* Temporarily remove all this source's file descriptors from the
1717 * poll(), so that if data comes available for one of the file descriptors
1718 * we don't continually spin in the poll()
1719 */
1720 /* HOLDS: source->context's lock */
1721 static void
block_source(GSource * source)1722 block_source (GSource *source)
1723 {
1724 GSList *tmp_list;
1725
1726 g_return_if_fail (!SOURCE_BLOCKED (source));
1727
1728 tmp_list = source->poll_fds;
1729 while (tmp_list)
1730 {
1731 g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
1732 tmp_list = tmp_list->next;
1733 }
1734 }
1735
1736 /* HOLDS: source->context's lock */
1737 static void
unblock_source(GSource * source)1738 unblock_source (GSource *source)
1739 {
1740 GSList *tmp_list;
1741
1742 g_return_if_fail (!SOURCE_BLOCKED (source)); /* Source already unblocked */
1743 g_return_if_fail (!SOURCE_DESTROYED (source));
1744
1745 tmp_list = source->poll_fds;
1746 while (tmp_list)
1747 {
1748 g_main_context_add_poll_unlocked (source->context, source->priority, tmp_list->data);
1749 tmp_list = tmp_list->next;
1750 }
1751 }
1752
1753 /* HOLDS: context's lock */
1754 static void
g_main_dispatch(GMainContext * context)1755 g_main_dispatch (GMainContext *context)
1756 {
1757 GMainDispatch *current = get_dispatch ();
1758 guint i;
1759
1760 for (i = 0; i < context->pending_dispatches->len; i++)
1761 {
1762 GSource *source = context->pending_dispatches->pdata[i];
1763
1764 context->pending_dispatches->pdata[i] = NULL;
1765 g_assert (source);
1766
1767 source->flags &= ~G_SOURCE_READY;
1768
1769 if (!SOURCE_DESTROYED (source))
1770 {
1771 gboolean was_in_call;
1772 gpointer user_data = NULL;
1773 GSourceFunc callback = NULL;
1774 GSourceCallbackFuncs *cb_funcs;
1775 gpointer cb_data;
1776 gboolean need_destroy;
1777
1778 gboolean (*dispatch) (GSource *,
1779 GSourceFunc,
1780 gpointer);
1781 GSList current_source_link;
1782
1783 dispatch = source->source_funcs->dispatch;
1784 cb_funcs = source->callback_funcs;
1785 cb_data = source->callback_data;
1786
1787 if (cb_funcs)
1788 cb_funcs->ref (cb_data);
1789
1790 if ((source->flags & G_SOURCE_CAN_RECURSE) == 0)
1791 block_source (source);
1792
1793 was_in_call = source->flags & G_HOOK_FLAG_IN_CALL;
1794 source->flags |= G_HOOK_FLAG_IN_CALL;
1795
1796 if (cb_funcs)
1797 cb_funcs->get (cb_data, source, &callback, &user_data);
1798
1799 UNLOCK_CONTEXT (context);
1800
1801 current->depth++;
1802 /* The on-stack allocation of the GSList is unconventional, but
1803 * we know that the lifetime of the link is bounded to this
1804 * function as the link is kept in a thread specific list and
1805 * not manipulated outside of this function and its descendants.
1806 * Avoiding the overhead of a g_slist_alloc() is useful as many
1807 * applications do little more than dispatch events.
1808 *
1809 * This is a performance hack - do not revert to g_slist_prepend()!
1810 */
1811 current_source_link.data = source;
1812 current_source_link.next = current->dispatching_sources;
1813 current->dispatching_sources = ¤t_source_link;
1814 need_destroy = ! dispatch (source,
1815 callback,
1816 user_data);
1817 g_assert (current->dispatching_sources == ¤t_source_link);
1818 current->dispatching_sources = current_source_link.next;
1819 current->depth--;
1820
1821 if (cb_funcs)
1822 cb_funcs->unref (cb_data);
1823
1824 LOCK_CONTEXT (context);
1825
1826 if (!was_in_call)
1827 source->flags &= ~G_HOOK_FLAG_IN_CALL;
1828
1829 if ((source->flags & G_SOURCE_CAN_RECURSE) == 0 &&
1830 !SOURCE_DESTROYED (source))
1831 unblock_source (source);
1832
1833 /* Note: this depends on the fact that we can't switch
1834 * sources from one main context to another
1835 */
1836 if (need_destroy && !SOURCE_DESTROYED (source))
1837 {
1838 g_assert (source->context == context);
1839 g_source_destroy_internal (source, context, TRUE);
1840 }
1841 }
1842
1843 SOURCE_UNREF (source, context);
1844 }
1845
1846 g_ptr_array_set_size (context->pending_dispatches, 0);
1847 }
1848
1849 /* Holds context's lock */
1850 static inline GSource *
next_valid_source(GMainContext * context,GSource * source)1851 next_valid_source (GMainContext *context,
1852 GSource *source)
1853 {
1854 GSource *new_source = source ? source->next : context->source_list;
1855
1856 while (new_source)
1857 {
1858 if (!SOURCE_DESTROYED (new_source))
1859 {
1860 new_source->ref_count++;
1861 break;
1862 }
1863
1864 new_source = new_source->next;
1865 }
1866
1867 if (source)
1868 SOURCE_UNREF (source, context);
1869
1870 return new_source;
1871 }
1872
1873 /**
1874 * g_main_context_acquire:
1875 * @context: a #GMainContext
1876 *
1877 * Tries to become the owner of the specified context.
1878 * If some other thread is the owner of the context,
1879 * returns %FALSE immediately. Ownership is properly
1880 * recursive: the owner can require ownership again
1881 * and will release ownership when g_main_context_release()
1882 * is called as many times as g_main_context_acquire().
1883 *
1884 * You must be the owner of a context before you
1885 * can call g_main_context_prepare(), g_main_context_query(),
1886 * g_main_context_check(), g_main_context_dispatch().
1887 *
1888 * Return value: %TRUE if the operation succeeded, and
1889 * this thread is now the owner of @context.
1890 **/
1891 gboolean
g_main_context_acquire(GMainContext * context)1892 g_main_context_acquire (GMainContext *context)
1893 {
1894 #ifdef G_THREADS_ENABLED
1895 gboolean result = FALSE;
1896 GThread *self = G_THREAD_SELF;
1897
1898 if (context == NULL)
1899 context = g_main_context_default ();
1900
1901 LOCK_CONTEXT (context);
1902
1903 if (!context->owner)
1904 {
1905 context->owner = self;
1906 g_assert (context->owner_count == 0);
1907 }
1908
1909 if (context->owner == self)
1910 {
1911 context->owner_count++;
1912 result = TRUE;
1913 }
1914
1915 UNLOCK_CONTEXT (context);
1916
1917 return result;
1918 #else /* !G_THREADS_ENABLED */
1919 return TRUE;
1920 #endif /* G_THREADS_ENABLED */
1921 }
1922
1923 /**
1924 * g_main_context_release:
1925 * @context: a #GMainContext
1926 *
1927 * Releases ownership of a context previously acquired by this thread
1928 * with g_main_context_acquire(). If the context was acquired multiple
1929 * times, the ownership will be released only when g_main_context_release()
1930 * is called as many times as it was acquired.
1931 **/
1932 void
g_main_context_release(GMainContext * context)1933 g_main_context_release (GMainContext *context)
1934 {
1935 #ifdef G_THREADS_ENABLED
1936 if (context == NULL)
1937 context = g_main_context_default ();
1938
1939 LOCK_CONTEXT (context);
1940
1941 context->owner_count--;
1942 if (context->owner_count == 0)
1943 {
1944 context->owner = NULL;
1945
1946 if (context->waiters)
1947 {
1948 GMainWaiter *waiter = context->waiters->data;
1949 gboolean loop_internal_waiter =
1950 (waiter->mutex == g_static_mutex_get_mutex (&context->mutex));
1951 context->waiters = g_slist_delete_link (context->waiters,
1952 context->waiters);
1953 if (!loop_internal_waiter)
1954 g_mutex_lock (waiter->mutex);
1955
1956 g_cond_signal (waiter->cond);
1957
1958 if (!loop_internal_waiter)
1959 g_mutex_unlock (waiter->mutex);
1960 }
1961 }
1962
1963 UNLOCK_CONTEXT (context);
1964 #endif /* G_THREADS_ENABLED */
1965 }
1966
1967 /**
1968 * g_main_context_wait:
1969 * @context: a #GMainContext
1970 * @cond: a condition variable
1971 * @mutex: a mutex, currently held
1972 *
1973 * Tries to become the owner of the specified context,
1974 * as with g_main_context_acquire(). But if another thread
1975 * is the owner, atomically drop @mutex and wait on @cond until
1976 * that owner releases ownership or until @cond is signaled, then
1977 * try again (once) to become the owner.
1978 *
1979 * Return value: %TRUE if the operation succeeded, and
1980 * this thread is now the owner of @context.
1981 **/
1982 gboolean
g_main_context_wait(GMainContext * context,GCond * cond,GMutex * mutex)1983 g_main_context_wait (GMainContext *context,
1984 GCond *cond,
1985 GMutex *mutex)
1986 {
1987 #ifdef G_THREADS_ENABLED
1988 gboolean result = FALSE;
1989 GThread *self = G_THREAD_SELF;
1990 gboolean loop_internal_waiter;
1991
1992 if (context == NULL)
1993 context = g_main_context_default ();
1994
1995 loop_internal_waiter = (mutex == g_static_mutex_get_mutex (&context->mutex));
1996
1997 if (!loop_internal_waiter)
1998 LOCK_CONTEXT (context);
1999
2000 if (context->owner && context->owner != self)
2001 {
2002 GMainWaiter waiter;
2003
2004 waiter.cond = cond;
2005 waiter.mutex = mutex;
2006
2007 context->waiters = g_slist_append (context->waiters, &waiter);
2008
2009 if (!loop_internal_waiter)
2010 UNLOCK_CONTEXT (context);
2011 g_cond_wait (cond, mutex);
2012 if (!loop_internal_waiter)
2013 LOCK_CONTEXT (context);
2014
2015 context->waiters = g_slist_remove (context->waiters, &waiter);
2016 }
2017
2018 if (!context->owner)
2019 {
2020 context->owner = self;
2021 g_assert (context->owner_count == 0);
2022 }
2023
2024 if (context->owner == self)
2025 {
2026 context->owner_count++;
2027 result = TRUE;
2028 }
2029
2030 if (!loop_internal_waiter)
2031 UNLOCK_CONTEXT (context);
2032
2033 return result;
2034 #else /* !G_THREADS_ENABLED */
2035 return TRUE;
2036 #endif /* G_THREADS_ENABLED */
2037 }
2038
2039 /**
2040 * g_main_context_prepare:
2041 * @context: a #GMainContext
2042 * @priority: location to store priority of highest priority
2043 * source already ready.
2044 *
2045 * Prepares to poll sources within a main loop. The resulting information
2046 * for polling is determined by calling g_main_context_query ().
2047 *
2048 * Return value: %TRUE if some source is ready to be dispatched
2049 * prior to polling.
2050 **/
2051 gboolean
g_main_context_prepare(GMainContext * context,gint * priority)2052 g_main_context_prepare (GMainContext *context,
2053 gint *priority)
2054 {
2055 gint i;
2056 gint n_ready = 0;
2057 gint current_priority = G_MAXINT;
2058 GSource *source;
2059
2060 if (context == NULL)
2061 context = g_main_context_default ();
2062
2063 LOCK_CONTEXT (context);
2064
2065 context->time_is_current = FALSE;
2066
2067 if (context->in_check_or_prepare)
2068 {
2069 g_warning ("g_main_context_prepare() called recursively from within a source's check() or "
2070 "prepare() member.");
2071 UNLOCK_CONTEXT (context);
2072 return FALSE;
2073 }
2074
2075 #ifdef G_THREADS_ENABLED
2076 if (context->poll_waiting)
2077 {
2078 g_warning("g_main_context_prepare(): main loop already active in another thread");
2079 UNLOCK_CONTEXT (context);
2080 return FALSE;
2081 }
2082
2083 context->poll_waiting = TRUE;
2084 #endif /* G_THREADS_ENABLED */
2085
2086 #if 0
2087 /* If recursing, finish up current dispatch, before starting over */
2088 if (context->pending_dispatches)
2089 {
2090 if (dispatch)
2091 g_main_dispatch (context, ¤t_time);
2092
2093 UNLOCK_CONTEXT (context);
2094 return TRUE;
2095 }
2096 #endif
2097
2098 /* If recursing, clear list of pending dispatches */
2099
2100 for (i = 0; i < context->pending_dispatches->len; i++)
2101 {
2102 if (context->pending_dispatches->pdata[i])
2103 SOURCE_UNREF ((GSource *)context->pending_dispatches->pdata[i], context);
2104 }
2105 g_ptr_array_set_size (context->pending_dispatches, 0);
2106
2107 /* Prepare all sources */
2108
2109 context->timeout = -1;
2110
2111 source = next_valid_source (context, NULL);
2112 while (source)
2113 {
2114 gint source_timeout = -1;
2115
2116 if ((n_ready > 0) && (source->priority > current_priority))
2117 {
2118 SOURCE_UNREF (source, context);
2119 break;
2120 }
2121 if (SOURCE_BLOCKED (source))
2122 goto next;
2123
2124 if (!(source->flags & G_SOURCE_READY))
2125 {
2126 gboolean result;
2127 gboolean (*prepare) (GSource *source,
2128 gint *timeout);
2129
2130 prepare = source->source_funcs->prepare;
2131 context->in_check_or_prepare++;
2132 UNLOCK_CONTEXT (context);
2133
2134 result = (*prepare) (source, &source_timeout);
2135
2136 LOCK_CONTEXT (context);
2137 context->in_check_or_prepare--;
2138
2139 if (result)
2140 source->flags |= G_SOURCE_READY;
2141 }
2142
2143 if (source->flags & G_SOURCE_READY)
2144 {
2145 n_ready++;
2146 current_priority = source->priority;
2147 context->timeout = 0;
2148 }
2149
2150 if (source_timeout >= 0)
2151 {
2152 if (context->timeout < 0)
2153 context->timeout = source_timeout;
2154 else
2155 context->timeout = MIN (context->timeout, source_timeout);
2156 }
2157
2158 next:
2159 source = next_valid_source (context, source);
2160 }
2161
2162 UNLOCK_CONTEXT (context);
2163
2164 if (priority)
2165 *priority = current_priority;
2166
2167 return (n_ready > 0);
2168 }
2169
2170 /**
2171 * g_main_context_query:
2172 * @context: a #GMainContext
2173 * @max_priority: maximum priority source to check
2174 * @timeout_: location to store timeout to be used in polling
2175 * @fds: location to store #GPollFD records that need to be polled.
2176 * @n_fds: length of @fds.
2177 *
2178 * Determines information necessary to poll this main loop.
2179 *
2180 * Return value: the number of records actually stored in @fds,
2181 * or, if more than @n_fds records need to be stored, the number
2182 * of records that need to be stored.
2183 **/
2184 gint
g_main_context_query(GMainContext * context,gint max_priority,gint * timeout,GPollFD * fds,gint n_fds)2185 g_main_context_query (GMainContext *context,
2186 gint max_priority,
2187 gint *timeout,
2188 GPollFD *fds,
2189 gint n_fds)
2190 {
2191 gint n_poll;
2192 GPollRec *pollrec;
2193
2194 LOCK_CONTEXT (context);
2195
2196 pollrec = context->poll_records;
2197 n_poll = 0;
2198 while (pollrec && max_priority >= pollrec->priority)
2199 {
2200 /* We need to include entries with fd->events == 0 in the array because
2201 * otherwise if the application changes fd->events behind our back and
2202 * makes it non-zero, we'll be out of sync when we check the fds[] array.
2203 * (Changing fd->events after adding an FD wasn't an anticipated use of
2204 * this API, but it occurs in practice.) */
2205 if (n_poll < n_fds)
2206 {
2207 fds[n_poll].fd = pollrec->fd->fd;
2208 /* In direct contradiction to the Unix98 spec, IRIX runs into
2209 * difficulty if you pass in POLLERR, POLLHUP or POLLNVAL
2210 * flags in the events field of the pollfd while it should
2211 * just ignoring them. So we mask them out here.
2212 */
2213 fds[n_poll].events = pollrec->fd->events & ~(G_IO_ERR|G_IO_HUP|G_IO_NVAL);
2214 fds[n_poll].revents = 0;
2215 }
2216
2217 pollrec = pollrec->next;
2218 n_poll++;
2219 }
2220
2221 #ifdef G_THREADS_ENABLED
2222 context->poll_changed = FALSE;
2223 #endif
2224
2225 if (timeout)
2226 {
2227 *timeout = context->timeout;
2228 if (*timeout != 0)
2229 context->time_is_current = FALSE;
2230 }
2231
2232 UNLOCK_CONTEXT (context);
2233
2234 return n_poll;
2235 }
2236
2237 /**
2238 * g_main_context_check:
2239 * @context: a #GMainContext
2240 * @max_priority: the maximum numerical priority of sources to check
2241 * @fds: array of #GPollFD's that was passed to the last call to
2242 * g_main_context_query()
2243 * @n_fds: return value of g_main_context_query()
2244 *
2245 * Passes the results of polling back to the main loop.
2246 *
2247 * Return value: %TRUE if some sources are ready to be dispatched.
2248 **/
2249 gboolean
g_main_context_check(GMainContext * context,gint max_priority,GPollFD * fds,gint n_fds)2250 g_main_context_check (GMainContext *context,
2251 gint max_priority,
2252 GPollFD *fds,
2253 gint n_fds)
2254 {
2255 GSource *source;
2256 GPollRec *pollrec;
2257 gint n_ready = 0;
2258 gint i;
2259
2260 LOCK_CONTEXT (context);
2261
2262 if (context->in_check_or_prepare)
2263 {
2264 g_warning ("g_main_context_check() called recursively from within a source's check() or "
2265 "prepare() member.");
2266 UNLOCK_CONTEXT (context);
2267 return FALSE;
2268 }
2269
2270 #ifdef G_THREADS_ENABLED
2271 if (!context->poll_waiting)
2272 {
2273 #ifndef G_OS_WIN32
2274 gchar a;
2275 read (context->wake_up_pipe[0], &a, 1);
2276 #endif
2277 }
2278 else
2279 context->poll_waiting = FALSE;
2280
2281 /* If the set of poll file descriptors changed, bail out
2282 * and let the main loop rerun
2283 */
2284 if (context->poll_changed)
2285 {
2286 UNLOCK_CONTEXT (context);
2287 return FALSE;
2288 }
2289 #endif /* G_THREADS_ENABLED */
2290
2291 pollrec = context->poll_records;
2292 i = 0;
2293 while (i < n_fds)
2294 {
2295 if (pollrec->fd->events)
2296 pollrec->fd->revents = fds[i].revents;
2297
2298 pollrec = pollrec->next;
2299 i++;
2300 }
2301
2302 source = next_valid_source (context, NULL);
2303 while (source)
2304 {
2305 if ((n_ready > 0) && (source->priority > max_priority))
2306 {
2307 SOURCE_UNREF (source, context);
2308 break;
2309 }
2310 if (SOURCE_BLOCKED (source))
2311 goto next;
2312
2313 if (!(source->flags & G_SOURCE_READY))
2314 {
2315 gboolean result;
2316 gboolean (*check) (GSource *source);
2317
2318 check = source->source_funcs->check;
2319
2320 context->in_check_or_prepare++;
2321 UNLOCK_CONTEXT (context);
2322
2323 result = (*check) (source);
2324
2325 LOCK_CONTEXT (context);
2326 context->in_check_or_prepare--;
2327
2328 if (result)
2329 source->flags |= G_SOURCE_READY;
2330 }
2331
2332 if (source->flags & G_SOURCE_READY)
2333 {
2334 source->ref_count++;
2335 g_ptr_array_add (context->pending_dispatches, source);
2336
2337 n_ready++;
2338
2339 /* never dispatch sources with less priority than the first
2340 * one we choose to dispatch
2341 */
2342 max_priority = source->priority;
2343 }
2344
2345 next:
2346 source = next_valid_source (context, source);
2347 }
2348
2349 UNLOCK_CONTEXT (context);
2350
2351 return n_ready > 0;
2352 }
2353
2354 /**
2355 * g_main_context_dispatch:
2356 * @context: a #GMainContext
2357 *
2358 * Dispatches all pending sources.
2359 **/
2360 void
g_main_context_dispatch(GMainContext * context)2361 g_main_context_dispatch (GMainContext *context)
2362 {
2363 LOCK_CONTEXT (context);
2364
2365 if (context->pending_dispatches->len > 0)
2366 {
2367 g_main_dispatch (context);
2368 }
2369
2370 UNLOCK_CONTEXT (context);
2371 }
2372
2373 /* HOLDS context lock */
2374 static gboolean
g_main_context_iterate(GMainContext * context,gboolean block,gboolean dispatch,GThread * self)2375 g_main_context_iterate (GMainContext *context,
2376 gboolean block,
2377 gboolean dispatch,
2378 GThread *self)
2379 {
2380 gint max_priority;
2381 gint timeout;
2382 gboolean some_ready;
2383 gint nfds, allocated_nfds;
2384 GPollFD *fds = NULL;
2385
2386 UNLOCK_CONTEXT (context);
2387
2388 #ifdef G_THREADS_ENABLED
2389 if (!g_main_context_acquire (context))
2390 {
2391 gboolean got_ownership;
2392
2393 LOCK_CONTEXT (context);
2394
2395 g_return_val_if_fail (g_thread_supported (), FALSE);
2396
2397 if (!block)
2398 return FALSE;
2399
2400 if (!context->cond)
2401 context->cond = g_cond_new ();
2402
2403 got_ownership = g_main_context_wait (context,
2404 context->cond,
2405 g_static_mutex_get_mutex (&context->mutex));
2406
2407 if (!got_ownership)
2408 return FALSE;
2409 }
2410 else
2411 LOCK_CONTEXT (context);
2412 #endif /* G_THREADS_ENABLED */
2413
2414 if (!context->cached_poll_array)
2415 {
2416 context->cached_poll_array_size = context->n_poll_records;
2417 context->cached_poll_array = g_new (GPollFD, context->n_poll_records);
2418 }
2419
2420 allocated_nfds = context->cached_poll_array_size;
2421 fds = context->cached_poll_array;
2422
2423 UNLOCK_CONTEXT (context);
2424
2425 g_main_context_prepare (context, &max_priority);
2426
2427 while ((nfds = g_main_context_query (context, max_priority, &timeout, fds,
2428 allocated_nfds)) > allocated_nfds)
2429 {
2430 LOCK_CONTEXT (context);
2431 g_free (fds);
2432 context->cached_poll_array_size = allocated_nfds = nfds;
2433 context->cached_poll_array = fds = g_new (GPollFD, nfds);
2434 UNLOCK_CONTEXT (context);
2435 }
2436
2437 if (!block)
2438 timeout = 0;
2439
2440 g_main_context_poll (context, timeout, max_priority, fds, nfds);
2441
2442 some_ready = g_main_context_check (context, max_priority, fds, nfds);
2443
2444 if (dispatch)
2445 g_main_context_dispatch (context);
2446
2447 #ifdef G_THREADS_ENABLED
2448 g_main_context_release (context);
2449 #endif /* G_THREADS_ENABLED */
2450
2451 LOCK_CONTEXT (context);
2452
2453 return some_ready;
2454 }
2455
2456 /**
2457 * g_main_context_pending:
2458 * @context: a #GMainContext (if %NULL, the default context will be used)
2459 *
2460 * Checks if any sources have pending events for the given context.
2461 *
2462 * Return value: %TRUE if events are pending.
2463 **/
2464 gboolean
g_main_context_pending(GMainContext * context)2465 g_main_context_pending (GMainContext *context)
2466 {
2467 gboolean retval;
2468
2469 if (!context)
2470 context = g_main_context_default();
2471
2472 LOCK_CONTEXT (context);
2473 retval = g_main_context_iterate (context, FALSE, FALSE, G_THREAD_SELF);
2474 UNLOCK_CONTEXT (context);
2475
2476 return retval;
2477 }
2478
2479 /**
2480 * g_main_context_iteration:
2481 * @context: a #GMainContext (if %NULL, the default context will be used)
2482 * @may_block: whether the call may block.
2483 *
2484 * Runs a single iteration for the given main loop. This involves
2485 * checking to see if any event sources are ready to be processed,
2486 * then if no events sources are ready and @may_block is %TRUE, waiting
2487 * for a source to become ready, then dispatching the highest priority
2488 * events sources that are ready. Otherwise, if @may_block is %FALSE
2489 * sources are not waited to become ready, only those highest priority
2490 * events sources will be dispatched (if any), that are ready at this
2491 * given moment without further waiting.
2492 *
2493 * Note that even when @may_block is %TRUE, it is still possible for
2494 * g_main_context_iteration() to return %FALSE, since the the wait may
2495 * be interrupted for other reasons than an event source becoming ready.
2496 *
2497 * Return value: %TRUE if events were dispatched.
2498 **/
2499 gboolean
g_main_context_iteration(GMainContext * context,gboolean may_block)2500 g_main_context_iteration (GMainContext *context, gboolean may_block)
2501 {
2502 gboolean retval;
2503
2504 if (!context)
2505 context = g_main_context_default();
2506
2507 LOCK_CONTEXT (context);
2508 retval = g_main_context_iterate (context, may_block, TRUE, G_THREAD_SELF);
2509 UNLOCK_CONTEXT (context);
2510
2511 return retval;
2512 }
2513
2514 /**
2515 * g_main_loop_new:
2516 * @context: a #GMainContext (if %NULL, the default context will be used).
2517 * @is_running: set to %TRUE to indicate that the loop is running. This
2518 * is not very important since calling g_main_loop_run() will set this to
2519 * %TRUE anyway.
2520 *
2521 * Creates a new #GMainLoop structure.
2522 *
2523 * Return value: a new #GMainLoop.
2524 **/
2525 GMainLoop *
g_main_loop_new(GMainContext * context,gboolean is_running)2526 g_main_loop_new (GMainContext *context,
2527 gboolean is_running)
2528 {
2529 GMainLoop *loop;
2530
2531 if (!context)
2532 context = g_main_context_default();
2533
2534 g_main_context_ref (context);
2535
2536 loop = g_new0 (GMainLoop, 1);
2537 loop->context = context;
2538 loop->is_running = is_running != FALSE;
2539 loop->ref_count = 1;
2540
2541 return loop;
2542 }
2543
2544 /**
2545 * g_main_loop_ref:
2546 * @loop: a #GMainLoop
2547 *
2548 * Increases the reference count on a #GMainLoop object by one.
2549 *
2550 * Return value: @loop
2551 **/
2552 GMainLoop *
g_main_loop_ref(GMainLoop * loop)2553 g_main_loop_ref (GMainLoop *loop)
2554 {
2555 g_return_val_if_fail (loop != NULL, NULL);
2556 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
2557
2558 g_atomic_int_inc (&loop->ref_count);
2559
2560 return loop;
2561 }
2562
2563 /**
2564 * g_main_loop_unref:
2565 * @loop: a #GMainLoop
2566 *
2567 * Decreases the reference count on a #GMainLoop object by one. If
2568 * the result is zero, free the loop and free all associated memory.
2569 **/
2570 void
g_main_loop_unref(GMainLoop * loop)2571 g_main_loop_unref (GMainLoop *loop)
2572 {
2573 g_return_if_fail (loop != NULL);
2574 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
2575
2576 if (!g_atomic_int_dec_and_test (&loop->ref_count))
2577 return;
2578
2579 g_main_context_unref (loop->context);
2580 g_free (loop);
2581 }
2582
2583 /**
2584 * g_main_loop_run:
2585 * @loop: a #GMainLoop
2586 *
2587 * Runs a main loop until g_main_loop_quit() is called on the loop.
2588 * If this is called for the thread of the loop's #GMainContext,
2589 * it will process events from the loop, otherwise it will
2590 * simply wait.
2591 **/
2592 void
g_main_loop_run(GMainLoop * loop)2593 g_main_loop_run (GMainLoop *loop)
2594 {
2595 GThread *self = G_THREAD_SELF;
2596
2597 g_return_if_fail (loop != NULL);
2598 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
2599
2600 #ifdef G_THREADS_ENABLED
2601 if (!g_main_context_acquire (loop->context))
2602 {
2603 gboolean got_ownership = FALSE;
2604
2605 /* Another thread owns this context */
2606 if (!g_thread_supported ())
2607 {
2608 g_warning ("g_main_loop_run() was called from second thread but "
2609 "g_thread_init() was never called.");
2610 return;
2611 }
2612
2613 LOCK_CONTEXT (loop->context);
2614
2615 g_atomic_int_inc (&loop->ref_count);
2616
2617 if (!loop->is_running)
2618 loop->is_running = TRUE;
2619
2620 if (!loop->context->cond)
2621 loop->context->cond = g_cond_new ();
2622
2623 while (loop->is_running && !got_ownership)
2624 got_ownership = g_main_context_wait (loop->context,
2625 loop->context->cond,
2626 g_static_mutex_get_mutex (&loop->context->mutex));
2627
2628 if (!loop->is_running)
2629 {
2630 UNLOCK_CONTEXT (loop->context);
2631 if (got_ownership)
2632 g_main_context_release (loop->context);
2633 g_main_loop_unref (loop);
2634 return;
2635 }
2636
2637 g_assert (got_ownership);
2638 }
2639 else
2640 LOCK_CONTEXT (loop->context);
2641 #endif /* G_THREADS_ENABLED */
2642
2643 if (loop->context->in_check_or_prepare)
2644 {
2645 g_warning ("g_main_loop_run(): called recursively from within a source's "
2646 "check() or prepare() member, iteration not possible.");
2647 return;
2648 }
2649
2650 g_atomic_int_inc (&loop->ref_count);
2651 loop->is_running = TRUE;
2652 while (loop->is_running)
2653 g_main_context_iterate (loop->context, TRUE, TRUE, self);
2654
2655 UNLOCK_CONTEXT (loop->context);
2656
2657 #ifdef G_THREADS_ENABLED
2658 g_main_context_release (loop->context);
2659 #endif /* G_THREADS_ENABLED */
2660
2661 g_main_loop_unref (loop);
2662 }
2663
2664 /**
2665 * g_main_loop_quit:
2666 * @loop: a #GMainLoop
2667 *
2668 * Stops a #GMainLoop from running. Any calls to g_main_loop_run()
2669 * for the loop will return.
2670 *
2671 * Note that sources that have already been dispatched when
2672 * g_main_loop_quit() is called will still be executed.
2673 **/
2674 void
g_main_loop_quit(GMainLoop * loop)2675 g_main_loop_quit (GMainLoop *loop)
2676 {
2677 g_return_if_fail (loop != NULL);
2678 g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0);
2679
2680 LOCK_CONTEXT (loop->context);
2681 loop->is_running = FALSE;
2682 g_main_context_wakeup_unlocked (loop->context);
2683
2684 #ifdef G_THREADS_ENABLED
2685 if (loop->context->cond)
2686 g_cond_broadcast (loop->context->cond);
2687 #endif /* G_THREADS_ENABLED */
2688
2689 UNLOCK_CONTEXT (loop->context);
2690 }
2691
2692 /**
2693 * g_main_loop_is_running:
2694 * @loop: a #GMainLoop.
2695 *
2696 * Checks to see if the main loop is currently being run via g_main_loop_run().
2697 *
2698 * Return value: %TRUE if the mainloop is currently being run.
2699 **/
2700 gboolean
g_main_loop_is_running(GMainLoop * loop)2701 g_main_loop_is_running (GMainLoop *loop)
2702 {
2703 g_return_val_if_fail (loop != NULL, FALSE);
2704 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, FALSE);
2705
2706 return loop->is_running;
2707 }
2708
2709 /**
2710 * g_main_loop_get_context:
2711 * @loop: a #GMainLoop.
2712 *
2713 * Returns the #GMainContext of @loop.
2714 *
2715 * Return value: the #GMainContext of @loop
2716 **/
2717 GMainContext *
g_main_loop_get_context(GMainLoop * loop)2718 g_main_loop_get_context (GMainLoop *loop)
2719 {
2720 g_return_val_if_fail (loop != NULL, NULL);
2721 g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL);
2722
2723 return loop->context;
2724 }
2725
2726 /* HOLDS: context's lock */
2727 static void
g_main_context_poll(GMainContext * context,gint timeout,gint priority,GPollFD * fds,gint n_fds)2728 g_main_context_poll (GMainContext *context,
2729 gint timeout,
2730 gint priority,
2731 GPollFD *fds,
2732 gint n_fds)
2733 {
2734 #ifdef G_MAIN_POLL_DEBUG
2735 GTimer *poll_timer;
2736 GPollRec *pollrec;
2737 gint i;
2738 #endif
2739
2740 GPollFunc poll_func;
2741
2742 if (n_fds || timeout != 0)
2743 {
2744 #ifdef G_MAIN_POLL_DEBUG
2745 if (_g_main_poll_debug)
2746 {
2747 g_print ("polling context=%p n=%d timeout=%d\n",
2748 context, n_fds, timeout);
2749 poll_timer = g_timer_new ();
2750 }
2751 #endif
2752
2753 LOCK_CONTEXT (context);
2754
2755 poll_func = context->poll_func;
2756
2757 UNLOCK_CONTEXT (context);
2758 if ((*poll_func) (fds, n_fds, timeout) < 0 && errno != EINTR)
2759 {
2760 #ifndef G_OS_WIN32
2761 g_warning ("poll(2) failed due to: %s.",
2762 g_strerror (errno));
2763 #else
2764 /* If g_poll () returns -1, it has already called g_warning() */
2765 #endif
2766 }
2767
2768 #ifdef G_MAIN_POLL_DEBUG
2769 if (_g_main_poll_debug)
2770 {
2771 LOCK_CONTEXT (context);
2772
2773 g_print ("g_main_poll(%d) timeout: %d - elapsed %12.10f seconds",
2774 n_fds,
2775 timeout,
2776 g_timer_elapsed (poll_timer, NULL));
2777 g_timer_destroy (poll_timer);
2778 pollrec = context->poll_records;
2779
2780 while (pollrec != NULL)
2781 {
2782 i = 0;
2783 while (i < n_fds)
2784 {
2785 if (fds[i].fd == pollrec->fd->fd &&
2786 pollrec->fd->events &&
2787 fds[i].revents)
2788 {
2789 g_print (" [" G_POLLFD_FORMAT " :", fds[i].fd);
2790 if (fds[i].revents & G_IO_IN)
2791 g_print ("i");
2792 if (fds[i].revents & G_IO_OUT)
2793 g_print ("o");
2794 if (fds[i].revents & G_IO_PRI)
2795 g_print ("p");
2796 if (fds[i].revents & G_IO_ERR)
2797 g_print ("e");
2798 if (fds[i].revents & G_IO_HUP)
2799 g_print ("h");
2800 if (fds[i].revents & G_IO_NVAL)
2801 g_print ("n");
2802 g_print ("]");
2803 }
2804 i++;
2805 }
2806 pollrec = pollrec->next;
2807 }
2808 g_print ("\n");
2809
2810 UNLOCK_CONTEXT (context);
2811 }
2812 #endif
2813 } /* if (n_fds || timeout != 0) */
2814 }
2815
2816 /**
2817 * g_main_context_add_poll:
2818 * @context: a #GMainContext (or %NULL for the default context)
2819 * @fd: a #GPollFD structure holding information about a file
2820 * descriptor to watch.
2821 * @priority: the priority for this file descriptor which should be
2822 * the same as the priority used for g_source_attach() to ensure that the
2823 * file descriptor is polled whenever the results may be needed.
2824 *
2825 * Adds a file descriptor to the set of file descriptors polled for
2826 * this context. This will very seldomly be used directly. Instead
2827 * a typical event source will use g_source_add_poll() instead.
2828 **/
2829 void
g_main_context_add_poll(GMainContext * context,GPollFD * fd,gint priority)2830 g_main_context_add_poll (GMainContext *context,
2831 GPollFD *fd,
2832 gint priority)
2833 {
2834 if (!context)
2835 context = g_main_context_default ();
2836
2837 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
2838 g_return_if_fail (fd);
2839
2840 LOCK_CONTEXT (context);
2841 g_main_context_add_poll_unlocked (context, priority, fd);
2842 UNLOCK_CONTEXT (context);
2843 }
2844
2845 /* HOLDS: main_loop_lock */
2846 static void
g_main_context_add_poll_unlocked(GMainContext * context,gint priority,GPollFD * fd)2847 g_main_context_add_poll_unlocked (GMainContext *context,
2848 gint priority,
2849 GPollFD *fd)
2850 {
2851 GPollRec *lastrec, *pollrec;
2852 GPollRec *newrec = g_slice_new (GPollRec);
2853
2854 /* This file descriptor may be checked before we ever poll */
2855 fd->revents = 0;
2856 newrec->fd = fd;
2857 newrec->priority = priority;
2858
2859 lastrec = NULL;
2860 pollrec = context->poll_records;
2861 while (pollrec && priority >= pollrec->priority)
2862 {
2863 lastrec = pollrec;
2864 pollrec = pollrec->next;
2865 }
2866
2867 if (lastrec)
2868 lastrec->next = newrec;
2869 else
2870 context->poll_records = newrec;
2871
2872 newrec->next = pollrec;
2873
2874 context->n_poll_records++;
2875
2876 #ifdef G_THREADS_ENABLED
2877 context->poll_changed = TRUE;
2878
2879 /* Now wake up the main loop if it is waiting in the poll() */
2880 g_main_context_wakeup_unlocked (context);
2881 #endif
2882 }
2883
2884 /**
2885 * g_main_context_remove_poll:
2886 * @context:a #GMainContext
2887 * @fd: a #GPollFD descriptor previously added with g_main_context_add_poll()
2888 *
2889 * Removes file descriptor from the set of file descriptors to be
2890 * polled for a particular context.
2891 **/
2892 void
g_main_context_remove_poll(GMainContext * context,GPollFD * fd)2893 g_main_context_remove_poll (GMainContext *context,
2894 GPollFD *fd)
2895 {
2896 if (!context)
2897 context = g_main_context_default ();
2898
2899 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
2900 g_return_if_fail (fd);
2901
2902 LOCK_CONTEXT (context);
2903 g_main_context_remove_poll_unlocked (context, fd);
2904 UNLOCK_CONTEXT (context);
2905 }
2906
2907 static void
g_main_context_remove_poll_unlocked(GMainContext * context,GPollFD * fd)2908 g_main_context_remove_poll_unlocked (GMainContext *context,
2909 GPollFD *fd)
2910 {
2911 GPollRec *pollrec, *lastrec;
2912
2913 lastrec = NULL;
2914 pollrec = context->poll_records;
2915
2916 while (pollrec)
2917 {
2918 if (pollrec->fd == fd)
2919 {
2920 if (lastrec != NULL)
2921 lastrec->next = pollrec->next;
2922 else
2923 context->poll_records = pollrec->next;
2924
2925 g_slice_free (GPollRec, pollrec);
2926
2927 context->n_poll_records--;
2928 break;
2929 }
2930 lastrec = pollrec;
2931 pollrec = pollrec->next;
2932 }
2933
2934 #ifdef G_THREADS_ENABLED
2935 context->poll_changed = TRUE;
2936
2937 /* Now wake up the main loop if it is waiting in the poll() */
2938 g_main_context_wakeup_unlocked (context);
2939 #endif
2940 }
2941
2942 /**
2943 * g_source_get_current_time:
2944 * @source: a #GSource
2945 * @timeval: #GTimeVal structure in which to store current time.
2946 *
2947 * Gets the "current time" to be used when checking
2948 * this source. The advantage of calling this function over
2949 * calling g_get_current_time() directly is that when
2950 * checking multiple sources, GLib can cache a single value
2951 * instead of having to repeatedly get the system time.
2952 **/
2953 void
g_source_get_current_time(GSource * source,GTimeVal * timeval)2954 g_source_get_current_time (GSource *source,
2955 GTimeVal *timeval)
2956 {
2957 GMainContext *context;
2958
2959 g_return_if_fail (source->context != NULL);
2960
2961 context = source->context;
2962
2963 LOCK_CONTEXT (context);
2964
2965 if (!context->time_is_current)
2966 {
2967 g_get_current_time (&context->current_time);
2968 context->time_is_current = TRUE;
2969 }
2970
2971 *timeval = context->current_time;
2972
2973 UNLOCK_CONTEXT (context);
2974 }
2975
2976 /**
2977 * g_main_context_set_poll_func:
2978 * @context: a #GMainContext
2979 * @func: the function to call to poll all file descriptors
2980 *
2981 * Sets the function to use to handle polling of file descriptors. It
2982 * will be used instead of the poll() system call
2983 * (or GLib's replacement function, which is used where
2984 * poll() isn't available).
2985 *
2986 * This function could possibly be used to integrate the GLib event
2987 * loop with an external event loop.
2988 **/
2989 void
g_main_context_set_poll_func(GMainContext * context,GPollFunc func)2990 g_main_context_set_poll_func (GMainContext *context,
2991 GPollFunc func)
2992 {
2993 if (!context)
2994 context = g_main_context_default ();
2995
2996 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
2997
2998 LOCK_CONTEXT (context);
2999
3000 if (func)
3001 context->poll_func = func;
3002 else
3003 context->poll_func = g_poll;
3004
3005 UNLOCK_CONTEXT (context);
3006 }
3007
3008 /**
3009 * g_main_context_get_poll_func:
3010 * @context: a #GMainContext
3011 *
3012 * Gets the poll function set by g_main_context_set_poll_func().
3013 *
3014 * Return value: the poll function
3015 **/
3016 GPollFunc
g_main_context_get_poll_func(GMainContext * context)3017 g_main_context_get_poll_func (GMainContext *context)
3018 {
3019 GPollFunc result;
3020
3021 if (!context)
3022 context = g_main_context_default ();
3023
3024 g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL);
3025
3026 LOCK_CONTEXT (context);
3027 result = context->poll_func;
3028 UNLOCK_CONTEXT (context);
3029
3030 return result;
3031 }
3032
3033 /* HOLDS: context's lock */
3034 /* Wake the main loop up from a poll() */
3035 static void
g_main_context_wakeup_unlocked(GMainContext * context)3036 g_main_context_wakeup_unlocked (GMainContext *context)
3037 {
3038 #ifdef G_THREADS_ENABLED
3039 if (g_thread_supported() && context->poll_waiting)
3040 {
3041 context->poll_waiting = FALSE;
3042 #ifndef G_OS_WIN32
3043 write (context->wake_up_pipe[1], "A", 1);
3044 #else
3045 ReleaseSemaphore (context->wake_up_semaphore, 1, NULL);
3046 #endif
3047 }
3048 #endif
3049 }
3050
3051 /**
3052 * g_main_context_wakeup:
3053 * @context: a #GMainContext
3054 *
3055 * If @context is currently waiting in a poll(), interrupt
3056 * the poll(), and continue the iteration process.
3057 **/
3058 void
g_main_context_wakeup(GMainContext * context)3059 g_main_context_wakeup (GMainContext *context)
3060 {
3061 if (!context)
3062 context = g_main_context_default ();
3063
3064 g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
3065
3066 LOCK_CONTEXT (context);
3067 g_main_context_wakeup_unlocked (context);
3068 UNLOCK_CONTEXT (context);
3069 }
3070
3071 /**
3072 * g_main_context_is_owner:
3073 * @context: a #GMainContext
3074 *
3075 * Determines whether this thread holds the (recursive)
3076 * ownership of this #GMaincontext. This is useful to
3077 * know before waiting on another thread that may be
3078 * blocking to get ownership of @context.
3079 *
3080 * Returns: %TRUE if current thread is owner of @context.
3081 *
3082 * Since: 2.10
3083 **/
3084 gboolean
g_main_context_is_owner(GMainContext * context)3085 g_main_context_is_owner (GMainContext *context)
3086 {
3087 gboolean is_owner;
3088
3089 if (!context)
3090 context = g_main_context_default ();
3091
3092 #ifdef G_THREADS_ENABLED
3093 LOCK_CONTEXT (context);
3094 is_owner = context->owner == G_THREAD_SELF;
3095 UNLOCK_CONTEXT (context);
3096 #else
3097 is_owner = TRUE;
3098 #endif
3099
3100 return is_owner;
3101 }
3102
3103 /* Timeouts */
3104
3105 static void
g_timeout_set_expiration(GTimeoutSource * timeout_source,GTimeVal * current_time)3106 g_timeout_set_expiration (GTimeoutSource *timeout_source,
3107 GTimeVal *current_time)
3108 {
3109 guint seconds = timeout_source->interval / 1000;
3110 guint msecs = timeout_source->interval - seconds * 1000;
3111
3112 timeout_source->expiration.tv_sec = current_time->tv_sec + seconds;
3113 timeout_source->expiration.tv_usec = current_time->tv_usec + msecs * 1000;
3114 if (timeout_source->expiration.tv_usec >= 1000000)
3115 {
3116 timeout_source->expiration.tv_usec -= 1000000;
3117 timeout_source->expiration.tv_sec++;
3118 }
3119 if (timer_perturb==-1)
3120 {
3121 /*
3122 * we want a per machine/session unique 'random' value; try the dbus
3123 * address first, that has a UUID in it. If there is no dbus, use the
3124 * hostname for hashing.
3125 */
3126 const char *session_bus_address = g_getenv ("DBUS_SESSION_BUS_ADDRESS");
3127 if (!session_bus_address)
3128 session_bus_address = g_getenv ("HOSTNAME");
3129 if (session_bus_address)
3130 timer_perturb = ABS ((gint) g_str_hash (session_bus_address));
3131 else
3132 timer_perturb = 0;
3133 }
3134 if (timeout_source->granularity)
3135 {
3136 gint remainder;
3137 gint gran; /* in usecs */
3138 gint perturb;
3139
3140 gran = timeout_source->granularity * 1000;
3141 perturb = timer_perturb % gran;
3142 /*
3143 * We want to give each machine a per machine pertubation;
3144 * shift time back first, and forward later after the rounding
3145 */
3146
3147 timeout_source->expiration.tv_usec -= perturb;
3148 if (timeout_source->expiration.tv_usec < 0)
3149 {
3150 timeout_source->expiration.tv_usec += 1000000;
3151 timeout_source->expiration.tv_sec--;
3152 }
3153
3154 remainder = timeout_source->expiration.tv_usec % gran;
3155 if (remainder >= gran/4) /* round up */
3156 timeout_source->expiration.tv_usec += gran;
3157 timeout_source->expiration.tv_usec -= remainder;
3158 /* shift back */
3159 timeout_source->expiration.tv_usec += perturb;
3160
3161 /* the rounding may have overflown tv_usec */
3162 while (timeout_source->expiration.tv_usec > 1000000)
3163 {
3164 timeout_source->expiration.tv_usec -= 1000000;
3165 timeout_source->expiration.tv_sec++;
3166 }
3167 }
3168 }
3169
3170 static gboolean
g_timeout_prepare(GSource * source,gint * timeout)3171 g_timeout_prepare (GSource *source,
3172 gint *timeout)
3173 {
3174 glong sec;
3175 glong msec;
3176 GTimeVal current_time;
3177
3178 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3179
3180 g_source_get_current_time (source, ¤t_time);
3181
3182 sec = timeout_source->expiration.tv_sec - current_time.tv_sec;
3183 msec = (timeout_source->expiration.tv_usec - current_time.tv_usec) / 1000;
3184
3185 /* We do the following in a rather convoluted fashion to deal with
3186 * the fact that we don't have an integral type big enough to hold
3187 * the difference of two timevals in millseconds.
3188 */
3189 if (sec < 0 || (sec == 0 && msec < 0))
3190 msec = 0;
3191 else
3192 {
3193 glong interval_sec = timeout_source->interval / 1000;
3194 glong interval_msec = timeout_source->interval % 1000;
3195
3196 if (msec < 0)
3197 {
3198 msec += 1000;
3199 sec -= 1;
3200 }
3201
3202 if (sec > interval_sec ||
3203 (sec == interval_sec && msec > interval_msec))
3204 {
3205 /* The system time has been set backwards, so we
3206 * reset the expiration time to now + timeout_source->interval;
3207 * this at least avoids hanging for long periods of time.
3208 */
3209 g_timeout_set_expiration (timeout_source, ¤t_time);
3210 msec = MIN (G_MAXINT, timeout_source->interval);
3211 }
3212 else
3213 {
3214 msec = MIN (G_MAXINT, (guint)msec + 1000 * (guint)sec);
3215 }
3216 }
3217
3218 *timeout = (gint)msec;
3219
3220 return msec == 0;
3221 }
3222
3223 static gboolean
g_timeout_check(GSource * source)3224 g_timeout_check (GSource *source)
3225 {
3226 GTimeVal current_time;
3227 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3228
3229 g_source_get_current_time (source, ¤t_time);
3230
3231 return ((timeout_source->expiration.tv_sec < current_time.tv_sec) ||
3232 ((timeout_source->expiration.tv_sec == current_time.tv_sec) &&
3233 (timeout_source->expiration.tv_usec <= current_time.tv_usec)));
3234 }
3235
3236 static gboolean
g_timeout_dispatch(GSource * source,GSourceFunc callback,gpointer user_data)3237 g_timeout_dispatch (GSource *source,
3238 GSourceFunc callback,
3239 gpointer user_data)
3240 {
3241 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3242
3243 if (!callback)
3244 {
3245 g_warning ("Timeout source dispatched without callback\n"
3246 "You must call g_source_set_callback().");
3247 return FALSE;
3248 }
3249
3250 if (callback (user_data))
3251 {
3252 GTimeVal current_time;
3253
3254 g_source_get_current_time (source, ¤t_time);
3255 g_timeout_set_expiration (timeout_source, ¤t_time);
3256
3257 return TRUE;
3258 }
3259 else
3260 return FALSE;
3261 }
3262
3263 /**
3264 * g_timeout_source_new:
3265 * @interval: the timeout interval in milliseconds.
3266 *
3267 * Creates a new timeout source.
3268 *
3269 * The source will not initially be associated with any #GMainContext
3270 * and must be added to one with g_source_attach() before it will be
3271 * executed.
3272 *
3273 * Return value: the newly-created timeout source
3274 **/
3275 GSource *
g_timeout_source_new(guint interval)3276 g_timeout_source_new (guint interval)
3277 {
3278 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
3279 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3280 GTimeVal current_time;
3281
3282 timeout_source->interval = interval;
3283
3284 g_get_current_time (¤t_time);
3285 g_timeout_set_expiration (timeout_source, ¤t_time);
3286
3287 return source;
3288 }
3289
3290 /**
3291 * g_timeout_source_new_seconds:
3292 * @interval: the timeout interval in seconds
3293 *
3294 * Creates a new timeout source.
3295 *
3296 * The source will not initially be associated with any #GMainContext
3297 * and must be added to one with g_source_attach() before it will be
3298 * executed.
3299 *
3300 * The scheduling granularity/accuracy of this timeout source will be
3301 * in seconds.
3302 *
3303 * Return value: the newly-created timeout source
3304 *
3305 * Since: 2.14
3306 **/
3307 GSource *
g_timeout_source_new_seconds(guint interval)3308 g_timeout_source_new_seconds (guint interval)
3309 {
3310 GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource));
3311 GTimeoutSource *timeout_source = (GTimeoutSource *)source;
3312 GTimeVal current_time;
3313
3314 timeout_source->interval = 1000*interval;
3315 timeout_source->granularity = 1000;
3316
3317 g_get_current_time (¤t_time);
3318 g_timeout_set_expiration (timeout_source, ¤t_time);
3319
3320 return source;
3321 }
3322
3323
3324 /**
3325 * g_timeout_add_full:
3326 * @priority: the priority of the timeout source. Typically this will be in
3327 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
3328 * @interval: the time between calls to the function, in milliseconds
3329 * (1/1000ths of a second)
3330 * @function: function to call
3331 * @data: data to pass to @function
3332 * @notify: function to call when the timeout is removed, or %NULL
3333 *
3334 * Sets a function to be called at regular intervals, with the given
3335 * priority. The function is called repeatedly until it returns
3336 * %FALSE, at which point the timeout is automatically destroyed and
3337 * the function will not be called again. The @notify function is
3338 * called when the timeout is destroyed. The first call to the
3339 * function will be at the end of the first @interval.
3340 *
3341 * Note that timeout functions may be delayed, due to the processing of other
3342 * event sources. Thus they should not be relied on for precise timing.
3343 * After each call to the timeout function, the time of the next
3344 * timeout is recalculated based on the current time and the given interval
3345 * (it does not try to 'catch up' time lost in delays).
3346 *
3347 * This internally creates a main loop source using g_timeout_source_new()
3348 * and attaches it to the main loop context using g_source_attach(). You can
3349 * do these steps manually if you need greater control.
3350 *
3351 * Return value: the ID (greater than 0) of the event source.
3352 **/
3353 guint
g_timeout_add_full(gint priority,guint interval,GSourceFunc function,gpointer data,GDestroyNotify notify)3354 g_timeout_add_full (gint priority,
3355 guint interval,
3356 GSourceFunc function,
3357 gpointer data,
3358 GDestroyNotify notify)
3359 {
3360 GSource *source;
3361 guint id;
3362
3363 g_return_val_if_fail (function != NULL, 0);
3364
3365 source = g_timeout_source_new (interval);
3366
3367 if (priority != G_PRIORITY_DEFAULT)
3368 g_source_set_priority (source, priority);
3369
3370 g_source_set_callback (source, function, data, notify);
3371 id = g_source_attach (source, NULL);
3372 g_source_unref (source);
3373
3374 return id;
3375 }
3376
3377 /**
3378 * g_timeout_add:
3379 * @interval: the time between calls to the function, in milliseconds
3380 * (1/1000ths of a second)
3381 * @function: function to call
3382 * @data: data to pass to @function
3383 *
3384 * Sets a function to be called at regular intervals, with the default
3385 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly
3386 * until it returns %FALSE, at which point the timeout is automatically
3387 * destroyed and the function will not be called again. The first call
3388 * to the function will be at the end of the first @interval.
3389 *
3390 * Note that timeout functions may be delayed, due to the processing of other
3391 * event sources. Thus they should not be relied on for precise timing.
3392 * After each call to the timeout function, the time of the next
3393 * timeout is recalculated based on the current time and the given interval
3394 * (it does not try to 'catch up' time lost in delays).
3395 *
3396 * If you want to have a timer in the "seconds" range and do not care
3397 * about the exact time of the first call of the timer, use the
3398 * g_timeout_add_seconds() function; this function allows for more
3399 * optimizations and more efficient system power usage.
3400 *
3401 * This internally creates a main loop source using g_timeout_source_new()
3402 * and attaches it to the main loop context using g_source_attach(). You can
3403 * do these steps manually if you need greater control.
3404 *
3405 * Return value: the ID (greater than 0) of the event source.
3406 **/
3407 guint
g_timeout_add(guint32 interval,GSourceFunc function,gpointer data)3408 g_timeout_add (guint32 interval,
3409 GSourceFunc function,
3410 gpointer data)
3411 {
3412 return g_timeout_add_full (G_PRIORITY_DEFAULT,
3413 interval, function, data, NULL);
3414 }
3415
3416 /**
3417 * g_timeout_add_seconds_full:
3418 * @priority: the priority of the timeout source. Typically this will be in
3419 * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH.
3420 * @interval: the time between calls to the function, in seconds
3421 * @function: function to call
3422 * @data: data to pass to @function
3423 * @notify: function to call when the timeout is removed, or %NULL
3424 *
3425 * Sets a function to be called at regular intervals, with @priority.
3426 * The function is called repeatedly until it returns %FALSE, at which
3427 * point the timeout is automatically destroyed and the function will
3428 * not be called again.
3429 *
3430 * Unlike g_timeout_add(), this function operates at whole second granularity.
3431 * The initial starting point of the timer is determined by the implementation
3432 * and the implementation is expected to group multiple timers together so that
3433 * they fire all at the same time.
3434 * To allow this grouping, the @interval to the first timer is rounded
3435 * and can deviate up to one second from the specified interval.
3436 * Subsequent timer iterations will generally run at the specified interval.
3437 *
3438 * Note that timeout functions may be delayed, due to the processing of other
3439 * event sources. Thus they should not be relied on for precise timing.
3440 * After each call to the timeout function, the time of the next
3441 * timeout is recalculated based on the current time and the given @interval
3442 *
3443 * If you want timing more precise than whole seconds, use g_timeout_add()
3444 * instead.
3445 *
3446 * The grouping of timers to fire at the same time results in a more power
3447 * and CPU efficient behavior so if your timer is in multiples of seconds
3448 * and you don't require the first timer exactly one second from now, the
3449 * use of g_timeout_add_seconds() is preferred over g_timeout_add().
3450 *
3451 * This internally creates a main loop source using
3452 * g_timeout_source_new_seconds() and attaches it to the main loop context
3453 * using g_source_attach(). You can do these steps manually if you need
3454 * greater control.
3455 *
3456 * Return value: the ID (greater than 0) of the event source.
3457 *
3458 * Since: 2.14
3459 **/
3460 guint
g_timeout_add_seconds_full(gint priority,guint32 interval,GSourceFunc function,gpointer data,GDestroyNotify notify)3461 g_timeout_add_seconds_full (gint priority,
3462 guint32 interval,
3463 GSourceFunc function,
3464 gpointer data,
3465 GDestroyNotify notify)
3466 {
3467 GSource *source;
3468 guint id;
3469
3470 g_return_val_if_fail (function != NULL, 0);
3471
3472 source = g_timeout_source_new_seconds (interval);
3473
3474 if (priority != G_PRIORITY_DEFAULT)
3475 g_source_set_priority (source, priority);
3476
3477 g_source_set_callback (source, function, data, notify);
3478 id = g_source_attach (source, NULL);
3479 g_source_unref (source);
3480
3481 return id;
3482 }
3483
3484 /**
3485 * g_timeout_add_seconds:
3486 * @interval: the time between calls to the function, in seconds
3487 * @function: function to call
3488 * @data: data to pass to @function
3489 *
3490 * Sets a function to be called at regular intervals with the default
3491 * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly until
3492 * it returns %FALSE, at which point the timeout is automatically destroyed
3493 * and the function will not be called again.
3494 *
3495 * This internally creates a main loop source using
3496 * g_timeout_source_new_seconds() and attaches it to the main loop context
3497 * using g_source_attach(). You can do these steps manually if you need
3498 * greater control. Also see g_timout_add_seconds_full().
3499 *
3500 * Return value: the ID (greater than 0) of the event source.
3501 *
3502 * Since: 2.14
3503 **/
3504 guint
g_timeout_add_seconds(guint interval,GSourceFunc function,gpointer data)3505 g_timeout_add_seconds (guint interval,
3506 GSourceFunc function,
3507 gpointer data)
3508 {
3509 g_return_val_if_fail (function != NULL, 0);
3510
3511 return g_timeout_add_seconds_full (G_PRIORITY_DEFAULT, interval, function, data, NULL);
3512 }
3513
3514 /* Child watch functions */
3515
3516 #ifdef G_OS_WIN32
3517
3518 static gboolean
g_child_watch_prepare(GSource * source,gint * timeout)3519 g_child_watch_prepare (GSource *source,
3520 gint *timeout)
3521 {
3522 *timeout = -1;
3523 return FALSE;
3524 }
3525
3526
3527 static gboolean
g_child_watch_check(GSource * source)3528 g_child_watch_check (GSource *source)
3529 {
3530 GChildWatchSource *child_watch_source;
3531 gboolean child_exited;
3532
3533 child_watch_source = (GChildWatchSource *) source;
3534
3535 child_exited = child_watch_source->poll.revents & G_IO_IN;
3536
3537 if (child_exited)
3538 {
3539 DWORD child_status;
3540
3541 /*
3542 * Note: We do _not_ check for the special value of STILL_ACTIVE
3543 * since we know that the process has exited and doing so runs into
3544 * problems if the child process "happens to return STILL_ACTIVE(259)"
3545 * as Microsoft's Platform SDK puts it.
3546 */
3547 if (!GetExitCodeProcess (child_watch_source->pid, &child_status))
3548 {
3549 gchar *emsg = g_win32_error_message (GetLastError ());
3550 g_warning (G_STRLOC ": GetExitCodeProcess() failed: %s", emsg);
3551 g_free (emsg);
3552
3553 child_watch_source->child_status = -1;
3554 }
3555 else
3556 child_watch_source->child_status = child_status;
3557 }
3558
3559 return child_exited;
3560 }
3561
3562 #else /* G_OS_WIN32 */
3563
3564 static gboolean
check_for_child_exited(GSource * source)3565 check_for_child_exited (GSource *source)
3566 {
3567 GChildWatchSource *child_watch_source;
3568 gint count;
3569
3570 /* protect against another SIGCHLD in the middle of this call */
3571 count = child_watch_count;
3572
3573 child_watch_source = (GChildWatchSource *) source;
3574
3575 if (child_watch_source->child_exited)
3576 return TRUE;
3577
3578 if (child_watch_source->count < count)
3579 {
3580 gint child_status;
3581
3582 if (waitpid (child_watch_source->pid, &child_status, WNOHANG) > 0)
3583 {
3584 child_watch_source->child_status = child_status;
3585 child_watch_source->child_exited = TRUE;
3586 }
3587 child_watch_source->count = count;
3588 }
3589
3590 return child_watch_source->child_exited;
3591 }
3592
3593 static gboolean
g_child_watch_prepare(GSource * source,gint * timeout)3594 g_child_watch_prepare (GSource *source,
3595 gint *timeout)
3596 {
3597 *timeout = -1;
3598
3599 return check_for_child_exited (source);
3600 }
3601
3602
3603 static gboolean
g_child_watch_check(GSource * source)3604 g_child_watch_check (GSource *source)
3605 {
3606 return check_for_child_exited (source);
3607 }
3608
3609 #endif /* G_OS_WIN32 */
3610
3611 static gboolean
g_child_watch_dispatch(GSource * source,GSourceFunc callback,gpointer user_data)3612 g_child_watch_dispatch (GSource *source,
3613 GSourceFunc callback,
3614 gpointer user_data)
3615 {
3616 GChildWatchSource *child_watch_source;
3617 GChildWatchFunc child_watch_callback = (GChildWatchFunc) callback;
3618
3619 child_watch_source = (GChildWatchSource *) source;
3620
3621 if (!callback)
3622 {
3623 g_warning ("Child watch source dispatched without callback\n"
3624 "You must call g_source_set_callback().");
3625 return FALSE;
3626 }
3627
3628 (child_watch_callback) (child_watch_source->pid, child_watch_source->child_status, user_data);
3629
3630 /* We never keep a child watch source around as the child is gone */
3631 return FALSE;
3632 }
3633
3634 #ifndef G_OS_WIN32
3635
3636 static void
g_child_watch_signal_handler(int signum)3637 g_child_watch_signal_handler (int signum)
3638 {
3639 child_watch_count ++;
3640
3641 if (child_watch_init_state == CHILD_WATCH_INITIALIZED_THREADED)
3642 {
3643 write (child_watch_wake_up_pipe[1], "B", 1);
3644 }
3645 else
3646 {
3647 /* We count on the signal interrupting the poll in the same thread.
3648 */
3649 }
3650 }
3651
3652 static void
g_child_watch_source_init_single(void)3653 g_child_watch_source_init_single (void)
3654 {
3655 struct sigaction action;
3656
3657 g_assert (! g_thread_supported());
3658 g_assert (child_watch_init_state == CHILD_WATCH_UNINITIALIZED);
3659
3660 child_watch_init_state = CHILD_WATCH_INITIALIZED_SINGLE;
3661
3662 action.sa_handler = g_child_watch_signal_handler;
3663 sigemptyset (&action.sa_mask);
3664 action.sa_flags = SA_NOCLDSTOP;
3665 sigaction (SIGCHLD, &action, NULL);
3666 }
3667
3668 #ifndef ANDROID_STUB
3669 G_GNUC_NORETURN static gpointer
3670 #else
3671 void
3672 #endif
child_watch_helper_thread(gpointer data)3673 child_watch_helper_thread (gpointer data)
3674 {
3675 while (1)
3676 {
3677 gchar b[20];
3678 GSList *list;
3679
3680 read (child_watch_wake_up_pipe[0], b, 20);
3681
3682 /* We were woken up. Wake up all other contexts in all other threads */
3683 G_LOCK (main_context_list);
3684 for (list = main_context_list; list; list = list->next)
3685 {
3686 GMainContext *context;
3687
3688 context = list->data;
3689 if (g_atomic_int_get (&context->ref_count) > 0)
3690 /* Due to racing conditions we can find ref_count == 0, in
3691 * that case, however, the context is still not destroyed
3692 * and no poll can be active, otherwise the ref_count
3693 * wouldn't be 0 */
3694 g_main_context_wakeup (context);
3695 }
3696 G_UNLOCK (main_context_list);
3697 }
3698 }
3699
3700 static void
g_child_watch_source_init_multi_threaded(void)3701 g_child_watch_source_init_multi_threaded (void)
3702 {
3703 GError *error = NULL;
3704 struct sigaction action;
3705
3706 g_assert (g_thread_supported());
3707
3708 if (pipe (child_watch_wake_up_pipe) < 0)
3709 g_error ("Cannot create wake up pipe: %s\n", g_strerror (errno));
3710 fcntl (child_watch_wake_up_pipe[1], F_SETFL, O_NONBLOCK | fcntl (child_watch_wake_up_pipe[1], F_GETFL));
3711
3712 /* We create a helper thread that polls on the wakeup pipe indefinitely */
3713 /* FIXME: Think this through for races */
3714 if (g_thread_create (child_watch_helper_thread, NULL, FALSE, &error) == NULL)
3715 g_error ("Cannot create a thread to monitor child exit status: %s\n", error->message);
3716 child_watch_init_state = CHILD_WATCH_INITIALIZED_THREADED;
3717
3718 action.sa_handler = g_child_watch_signal_handler;
3719 sigemptyset (&action.sa_mask);
3720 action.sa_flags = SA_RESTART | SA_NOCLDSTOP;
3721 sigaction (SIGCHLD, &action, NULL);
3722 }
3723
3724 static void
g_child_watch_source_init_promote_single_to_threaded(void)3725 g_child_watch_source_init_promote_single_to_threaded (void)
3726 {
3727 g_child_watch_source_init_multi_threaded ();
3728 }
3729
3730 static void
g_child_watch_source_init(void)3731 g_child_watch_source_init (void)
3732 {
3733 if (g_thread_supported())
3734 {
3735 if (child_watch_init_state == CHILD_WATCH_UNINITIALIZED)
3736 g_child_watch_source_init_multi_threaded ();
3737 else if (child_watch_init_state == CHILD_WATCH_INITIALIZED_SINGLE)
3738 g_child_watch_source_init_promote_single_to_threaded ();
3739 }
3740 else
3741 {
3742 if (child_watch_init_state == CHILD_WATCH_UNINITIALIZED)
3743 g_child_watch_source_init_single ();
3744 }
3745 }
3746
3747 #endif /* !G_OS_WIN32 */
3748
3749 /**
3750 * g_child_watch_source_new:
3751 * @pid: process to watch. On POSIX the pid of a child process. On
3752 * Windows a handle for a process (which doesn't have to be a child).
3753 *
3754 * Creates a new child_watch source.
3755 *
3756 * The source will not initially be associated with any #GMainContext
3757 * and must be added to one with g_source_attach() before it will be
3758 * executed.
3759 *
3760 * Note that child watch sources can only be used in conjunction with
3761 * <literal>g_spawn...</literal> when the %G_SPAWN_DO_NOT_REAP_CHILD
3762 * flag is used.
3763 *
3764 * Note that on platforms where #GPid must be explicitly closed
3765 * (see g_spawn_close_pid()) @pid must not be closed while the
3766 * source is still active. Typically, you will want to call
3767 * g_spawn_close_pid() in the callback function for the source.
3768 *
3769 * Note further that using g_child_watch_source_new() is not
3770 * compatible with calling <literal>waitpid(-1)</literal> in
3771 * the application. Calling waitpid() for individual pids will
3772 * still work fine.
3773 *
3774 * Return value: the newly-created child watch source
3775 *
3776 * Since: 2.4
3777 **/
3778 GSource *
g_child_watch_source_new(GPid pid)3779 g_child_watch_source_new (GPid pid)
3780 {
3781 GSource *source = g_source_new (&g_child_watch_funcs, sizeof (GChildWatchSource));
3782 GChildWatchSource *child_watch_source = (GChildWatchSource *)source;
3783
3784 #ifdef G_OS_WIN32
3785 child_watch_source->poll.fd = (gintptr) pid;
3786 child_watch_source->poll.events = G_IO_IN;
3787
3788 g_source_add_poll (source, &child_watch_source->poll);
3789 #else /* G_OS_WIN32 */
3790 g_child_watch_source_init ();
3791 #endif /* G_OS_WIN32 */
3792
3793 child_watch_source->pid = pid;
3794
3795 return source;
3796 }
3797
3798 /**
3799 * g_child_watch_add_full:
3800 * @priority: the priority of the idle source. Typically this will be in the
3801 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
3802 * @pid: process to watch. On POSIX the pid of a child process. On
3803 * Windows a handle for a process (which doesn't have to be a child).
3804 * @function: function to call
3805 * @data: data to pass to @function
3806 * @notify: function to call when the idle is removed, or %NULL
3807 *
3808 * Sets a function to be called when the child indicated by @pid
3809 * exits, at the priority @priority.
3810 *
3811 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
3812 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
3813 * the spawn function for the child watching to work.
3814 *
3815 * Note that on platforms where #GPid must be explicitly closed
3816 * (see g_spawn_close_pid()) @pid must not be closed while the
3817 * source is still active. Typically, you will want to call
3818 * g_spawn_close_pid() in the callback function for the source.
3819 *
3820 * GLib supports only a single callback per process id.
3821 *
3822 * This internally creates a main loop source using
3823 * g_child_watch_source_new() and attaches it to the main loop context
3824 * using g_source_attach(). You can do these steps manually if you
3825 * need greater control.
3826 *
3827 * Return value: the ID (greater than 0) of the event source.
3828 *
3829 * Since: 2.4
3830 **/
3831 guint
g_child_watch_add_full(gint priority,GPid pid,GChildWatchFunc function,gpointer data,GDestroyNotify notify)3832 g_child_watch_add_full (gint priority,
3833 GPid pid,
3834 GChildWatchFunc function,
3835 gpointer data,
3836 GDestroyNotify notify)
3837 {
3838 GSource *source;
3839 guint id;
3840
3841 g_return_val_if_fail (function != NULL, 0);
3842
3843 source = g_child_watch_source_new (pid);
3844
3845 if (priority != G_PRIORITY_DEFAULT)
3846 g_source_set_priority (source, priority);
3847
3848 g_source_set_callback (source, (GSourceFunc) function, data, notify);
3849 id = g_source_attach (source, NULL);
3850 g_source_unref (source);
3851
3852 return id;
3853 }
3854
3855 /**
3856 * g_child_watch_add:
3857 * @pid: process id to watch. On POSIX the pid of a child process. On
3858 * Windows a handle for a process (which doesn't have to be a child).
3859 * @function: function to call
3860 * @data: data to pass to @function
3861 *
3862 * Sets a function to be called when the child indicated by @pid
3863 * exits, at a default priority, #G_PRIORITY_DEFAULT.
3864 *
3865 * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
3866 * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
3867 * the spawn function for the child watching to work.
3868 *
3869 * Note that on platforms where #GPid must be explicitly closed
3870 * (see g_spawn_close_pid()) @pid must not be closed while the
3871 * source is still active. Typically, you will want to call
3872 * g_spawn_close_pid() in the callback function for the source.
3873 *
3874 * GLib supports only a single callback per process id.
3875 *
3876 * This internally creates a main loop source using
3877 * g_child_watch_source_new() and attaches it to the main loop context
3878 * using g_source_attach(). You can do these steps manually if you
3879 * need greater control.
3880 *
3881 * Return value: the ID (greater than 0) of the event source.
3882 *
3883 * Since: 2.4
3884 **/
3885 guint
g_child_watch_add(GPid pid,GChildWatchFunc function,gpointer data)3886 g_child_watch_add (GPid pid,
3887 GChildWatchFunc function,
3888 gpointer data)
3889 {
3890 return g_child_watch_add_full (G_PRIORITY_DEFAULT, pid, function, data, NULL);
3891 }
3892
3893
3894 /* Idle functions */
3895
3896 static gboolean
g_idle_prepare(GSource * source,gint * timeout)3897 g_idle_prepare (GSource *source,
3898 gint *timeout)
3899 {
3900 *timeout = 0;
3901
3902 return TRUE;
3903 }
3904
3905 static gboolean
g_idle_check(GSource * source)3906 g_idle_check (GSource *source)
3907 {
3908 return TRUE;
3909 }
3910
3911 static gboolean
g_idle_dispatch(GSource * source,GSourceFunc callback,gpointer user_data)3912 g_idle_dispatch (GSource *source,
3913 GSourceFunc callback,
3914 gpointer user_data)
3915 {
3916 if (!callback)
3917 {
3918 g_warning ("Idle source dispatched without callback\n"
3919 "You must call g_source_set_callback().");
3920 return FALSE;
3921 }
3922
3923 return callback (user_data);
3924 }
3925
3926 /**
3927 * g_idle_source_new:
3928 *
3929 * Creates a new idle source.
3930 *
3931 * The source will not initially be associated with any #GMainContext
3932 * and must be added to one with g_source_attach() before it will be
3933 * executed. Note that the default priority for idle sources is
3934 * %G_PRIORITY_DEFAULT_IDLE, as compared to other sources which
3935 * have a default priority of %G_PRIORITY_DEFAULT.
3936 *
3937 * Return value: the newly-created idle source
3938 **/
3939 GSource *
g_idle_source_new(void)3940 g_idle_source_new (void)
3941 {
3942 GSource *source;
3943
3944 source = g_source_new (&g_idle_funcs, sizeof (GSource));
3945 g_source_set_priority (source, G_PRIORITY_DEFAULT_IDLE);
3946
3947 return source;
3948 }
3949
3950 /**
3951 * g_idle_add_full:
3952 * @priority: the priority of the idle source. Typically this will be in the
3953 * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
3954 * @function: function to call
3955 * @data: data to pass to @function
3956 * @notify: function to call when the idle is removed, or %NULL
3957 *
3958 * Adds a function to be called whenever there are no higher priority
3959 * events pending. If the function returns %FALSE it is automatically
3960 * removed from the list of event sources and will not be called again.
3961 *
3962 * This internally creates a main loop source using g_idle_source_new()
3963 * and attaches it to the main loop context using g_source_attach().
3964 * You can do these steps manually if you need greater control.
3965 *
3966 * Return value: the ID (greater than 0) of the event source.
3967 **/
3968 guint
g_idle_add_full(gint priority,GSourceFunc function,gpointer data,GDestroyNotify notify)3969 g_idle_add_full (gint priority,
3970 GSourceFunc function,
3971 gpointer data,
3972 GDestroyNotify notify)
3973 {
3974 GSource *source;
3975 guint id;
3976
3977 g_return_val_if_fail (function != NULL, 0);
3978
3979 source = g_idle_source_new ();
3980
3981 if (priority != G_PRIORITY_DEFAULT_IDLE)
3982 g_source_set_priority (source, priority);
3983
3984 g_source_set_callback (source, function, data, notify);
3985 id = g_source_attach (source, NULL);
3986 g_source_unref (source);
3987
3988 return id;
3989 }
3990
3991 /**
3992 * g_idle_add:
3993 * @function: function to call
3994 * @data: data to pass to @function.
3995 *
3996 * Adds a function to be called whenever there are no higher priority
3997 * events pending to the default main loop. The function is given the
3998 * default idle priority, #G_PRIORITY_DEFAULT_IDLE. If the function
3999 * returns %FALSE it is automatically removed from the list of event
4000 * sources and will not be called again.
4001 *
4002 * This internally creates a main loop source using g_idle_source_new()
4003 * and attaches it to the main loop context using g_source_attach().
4004 * You can do these steps manually if you need greater control.
4005 *
4006 * Return value: the ID (greater than 0) of the event source.
4007 **/
4008 guint
g_idle_add(GSourceFunc function,gpointer data)4009 g_idle_add (GSourceFunc function,
4010 gpointer data)
4011 {
4012 return g_idle_add_full (G_PRIORITY_DEFAULT_IDLE, function, data, NULL);
4013 }
4014
4015 /**
4016 * g_idle_remove_by_data:
4017 * @data: the data for the idle source's callback.
4018 *
4019 * Removes the idle function with the given data.
4020 *
4021 * Return value: %TRUE if an idle source was found and removed.
4022 **/
4023 gboolean
g_idle_remove_by_data(gpointer data)4024 g_idle_remove_by_data (gpointer data)
4025 {
4026 return g_source_remove_by_funcs_user_data (&g_idle_funcs, data);
4027 }
4028
4029 #define __G_MAIN_C__
4030 #include "galiasdef.c"
4031