1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * SPDX-License-Identifier: LGPL-2.1-or-later
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
21 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
22 * file for a list of people on the GLib Team. See the ChangeLog
23 * files for a list of changes. These files are distributed with
24 * GLib at ftp://ftp.gtk.org/pub/gtk/.
27 #ifndef __G_THREAD_H__
28 #define __G_THREAD_H__
30 #if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
31 #error "Only <glib.h> can be included directly."
34 #include <glib/gatomic.h>
35 #include <glib/gerror.h>
36 #include <glib/gutils.h>
40 #define G_THREAD_ERROR g_thread_error_quark ()
42 GQuark g_thread_error_quark (void);
46 G_THREAD_ERROR_AGAIN /* Resource temporarily unavailable */
49 typedef gpointer (*GThreadFunc) (gpointer user_data);
51 typedef struct _GThread GThread;
53 typedef union _GMutex GMutex;
54 typedef struct _GRecMutex GRecMutex;
55 typedef struct _GRWLock GRWLock;
56 typedef struct _GCond GCond;
57 typedef struct _GPrivate GPrivate;
58 typedef struct _GOnce GOnce;
88 #define G_PRIVATE_INIT(notify) { NULL, (notify), { NULL, NULL } }
93 GDestroyNotify notify;
99 G_ONCE_STATUS_NOTCALLED,
100 G_ONCE_STATUS_PROGRESS,
104 #define G_ONCE_INIT { G_ONCE_STATUS_NOTCALLED, NULL }
107 volatile GOnceStatus status;
108 volatile gpointer retval;
111 #define G_LOCK_NAME(name) g__ ## name ## _lock
112 #define G_LOCK_DEFINE_STATIC(name) static G_LOCK_DEFINE (name)
113 #define G_LOCK_DEFINE(name) GMutex G_LOCK_NAME (name)
114 #define G_LOCK_EXTERN(name) extern GMutex G_LOCK_NAME (name)
117 # define G_LOCK(name) G_STMT_START{ \
118 g_log (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG, \
119 "file %s: line %d (%s): locking: %s ", \
120 __FILE__, __LINE__, G_STRFUNC, \
122 g_mutex_lock (&G_LOCK_NAME (name)); \
124 # define G_UNLOCK(name) G_STMT_START{ \
125 g_log (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG, \
126 "file %s: line %d (%s): unlocking: %s ", \
127 __FILE__, __LINE__, G_STRFUNC, \
129 g_mutex_unlock (&G_LOCK_NAME (name)); \
131 # define G_TRYLOCK(name) \
132 (g_log (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG, \
133 "file %s: line %d (%s): try locking: %s ", \
134 __FILE__, __LINE__, G_STRFUNC, \
135 #name), g_mutex_trylock (&G_LOCK_NAME (name)))
136 #else /* !G_DEBUG_LOCKS */
137 # define G_LOCK(name) g_mutex_lock (&G_LOCK_NAME (name))
138 # define G_UNLOCK(name) g_mutex_unlock (&G_LOCK_NAME (name))
139 # define G_TRYLOCK(name) g_mutex_trylock (&G_LOCK_NAME (name))
140 #endif /* !G_DEBUG_LOCKS */
142 GLIB_AVAILABLE_IN_2_32
143 GThread * g_thread_ref (GThread *thread);
144 GLIB_AVAILABLE_IN_2_32
145 void g_thread_unref (GThread *thread);
146 GLIB_AVAILABLE_IN_2_32
147 GThread * g_thread_new (const gchar *name,
150 GLIB_AVAILABLE_IN_2_32
151 GThread * g_thread_try_new (const gchar *name,
155 GLIB_AVAILABLE_IN_ALL
156 GThread * g_thread_self (void);
157 GLIB_AVAILABLE_IN_ALL
158 void g_thread_exit (gpointer retval);
159 GLIB_AVAILABLE_IN_ALL
160 gpointer g_thread_join (GThread *thread);
161 GLIB_AVAILABLE_IN_ALL
162 void g_thread_yield (void);
165 GLIB_AVAILABLE_IN_2_32
166 void g_mutex_init (GMutex *mutex);
167 GLIB_AVAILABLE_IN_2_32
168 void g_mutex_clear (GMutex *mutex);
169 GLIB_AVAILABLE_IN_ALL
170 void g_mutex_lock (GMutex *mutex);
171 GLIB_AVAILABLE_IN_ALL
172 gboolean g_mutex_trylock (GMutex *mutex);
173 GLIB_AVAILABLE_IN_ALL
174 void g_mutex_unlock (GMutex *mutex);
176 GLIB_AVAILABLE_IN_2_32
177 void g_rw_lock_init (GRWLock *rw_lock);
178 GLIB_AVAILABLE_IN_2_32
179 void g_rw_lock_clear (GRWLock *rw_lock);
180 GLIB_AVAILABLE_IN_2_32
181 void g_rw_lock_writer_lock (GRWLock *rw_lock);
182 GLIB_AVAILABLE_IN_2_32
183 gboolean g_rw_lock_writer_trylock (GRWLock *rw_lock);
184 GLIB_AVAILABLE_IN_2_32
185 void g_rw_lock_writer_unlock (GRWLock *rw_lock);
186 GLIB_AVAILABLE_IN_2_32
187 void g_rw_lock_reader_lock (GRWLock *rw_lock);
188 GLIB_AVAILABLE_IN_2_32
189 gboolean g_rw_lock_reader_trylock (GRWLock *rw_lock);
190 GLIB_AVAILABLE_IN_2_32
191 void g_rw_lock_reader_unlock (GRWLock *rw_lock);
193 GLIB_AVAILABLE_IN_2_32
194 void g_rec_mutex_init (GRecMutex *rec_mutex);
195 GLIB_AVAILABLE_IN_2_32
196 void g_rec_mutex_clear (GRecMutex *rec_mutex);
197 GLIB_AVAILABLE_IN_2_32
198 void g_rec_mutex_lock (GRecMutex *rec_mutex);
199 GLIB_AVAILABLE_IN_2_32
200 gboolean g_rec_mutex_trylock (GRecMutex *rec_mutex);
201 GLIB_AVAILABLE_IN_2_32
202 void g_rec_mutex_unlock (GRecMutex *rec_mutex);
204 GLIB_AVAILABLE_IN_2_32
205 void g_cond_init (GCond *cond);
206 GLIB_AVAILABLE_IN_2_32
207 void g_cond_clear (GCond *cond);
208 GLIB_AVAILABLE_IN_ALL
209 void g_cond_wait (GCond *cond,
211 GLIB_AVAILABLE_IN_ALL
212 void g_cond_signal (GCond *cond);
213 GLIB_AVAILABLE_IN_ALL
214 void g_cond_broadcast (GCond *cond);
215 GLIB_AVAILABLE_IN_2_32
216 gboolean g_cond_wait_until (GCond *cond,
220 GLIB_AVAILABLE_IN_ALL
221 gpointer g_private_get (GPrivate *key);
222 GLIB_AVAILABLE_IN_ALL
223 void g_private_set (GPrivate *key,
225 GLIB_AVAILABLE_IN_2_32
226 void g_private_replace (GPrivate *key,
229 GLIB_AVAILABLE_IN_ALL
230 gpointer g_once_impl (GOnce *once,
233 GLIB_AVAILABLE_IN_ALL
234 gboolean g_once_init_enter (volatile void *location);
235 GLIB_AVAILABLE_IN_ALL
236 void g_once_init_leave (volatile void *location,
239 /* Use C11-style atomic extensions to check the fast path for status=ready. If
240 * they are not available, fall back to using a mutex and condition variable in
243 * On the C11-style codepath, only the load of once->status needs to be atomic,
244 * as the writes to it and once->retval in g_once_impl() are related by a
245 * happens-before relation. Release-acquire semantics are defined such that any
246 * atomic/non-atomic write which happens-before a store/release is guaranteed to
247 * be seen by the load/acquire of the same atomic variable. */
248 #if defined(G_ATOMIC_LOCK_FREE) && defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4) && defined(__ATOMIC_SEQ_CST)
249 # define g_once(once, func, arg) \
250 ((__atomic_load_n (&(once)->status, __ATOMIC_ACQUIRE) == G_ONCE_STATUS_READY) ? \
252 g_once_impl ((once), (func), (arg)))
254 # define g_once(once, func, arg) g_once_impl ((once), (func), (arg))
258 # define g_once_init_enter(location) \
259 (G_GNUC_EXTENSION ({ \
260 G_STATIC_ASSERT (sizeof *(location) == sizeof (gpointer)); \
261 (void) (0 ? (gpointer) *(location) : NULL); \
262 (!g_atomic_pointer_get (location) && \
263 g_once_init_enter (location)); \
265 # define g_once_init_leave(location, result) \
266 (G_GNUC_EXTENSION ({ \
267 G_STATIC_ASSERT (sizeof *(location) == sizeof (gpointer)); \
268 0 ? (void) (*(location) = (result)) : (void) 0; \
269 g_once_init_leave ((location), (gsize) (result)); \
272 # define g_once_init_enter(location) \
273 (g_once_init_enter((location)))
274 # define g_once_init_leave(location, result) \
275 (g_once_init_leave((location), (gsize) (result)))
278 GLIB_AVAILABLE_IN_2_36
279 guint g_get_num_processors (void);
284 * Opaque type. See g_mutex_locker_new() for details.
287 typedef void GMutexLocker;
290 * g_mutex_locker_new:
291 * @mutex: a mutex to lock
293 * Lock @mutex and return a new #GMutexLocker. Unlock with
294 * g_mutex_locker_free(). Using g_mutex_unlock() on @mutex
295 * while a #GMutexLocker exists can lead to undefined behaviour.
297 * No allocation is performed, it is equivalent to a g_mutex_lock() call.
299 * This is intended to be used with g_autoptr(). Note that g_autoptr()
300 * is only available when using GCC or clang, so the following example
301 * will only work with those compilers:
311 * my_object_do_stuff (MyObject *self)
313 * g_autoptr(GMutexLocker) locker = g_mutex_locker_new (&self->mutex);
315 * // Code with mutex locked here
318 * // No need to unlock
321 * // Optionally early unlock
322 * g_clear_pointer (&locker, g_mutex_locker_free);
324 * // Code with mutex unlocked here
328 * Returns: a #GMutexLocker
331 GLIB_AVAILABLE_STATIC_INLINE_IN_2_44
332 static inline GMutexLocker *
333 g_mutex_locker_new (GMutex *mutex)
335 g_mutex_lock (mutex);
336 return (GMutexLocker *) mutex;
340 * g_mutex_locker_free:
341 * @locker: a GMutexLocker
343 * Unlock @locker's mutex. See g_mutex_locker_new() for details.
345 * No memory is freed, it is equivalent to a g_mutex_unlock() call.
349 GLIB_AVAILABLE_STATIC_INLINE_IN_2_44
351 g_mutex_locker_free (GMutexLocker *locker)
353 g_mutex_unlock ((GMutex *) locker);
359 * Opaque type. See g_rec_mutex_locker_new() for details.
362 typedef void GRecMutexLocker;
365 * g_rec_mutex_locker_new:
366 * @rec_mutex: a recursive mutex to lock
368 * Lock @rec_mutex and return a new #GRecMutexLocker. Unlock with
369 * g_rec_mutex_locker_free(). Using g_rec_mutex_unlock() on @rec_mutex
370 * while a #GRecMutexLocker exists can lead to undefined behaviour.
372 * No allocation is performed, it is equivalent to a g_rec_mutex_lock() call.
374 * This is intended to be used with g_autoptr(). Note that g_autoptr()
375 * is only available when using GCC or clang, so the following example
376 * will only work with those compilers:
381 * GRecMutex rec_mutex;
386 * my_object_do_stuff (MyObject *self)
388 * g_autoptr(GRecMutexLocker) locker = g_rec_mutex_locker_new (&self->rec_mutex);
390 * // Code with rec_mutex locked here
393 * // No need to unlock
396 * // Optionally early unlock
397 * g_clear_pointer (&locker, g_rec_mutex_locker_free);
399 * // Code with rec_mutex unlocked here
403 * Returns: a #GRecMutexLocker
406 G_GNUC_BEGIN_IGNORE_DEPRECATIONS
407 GLIB_AVAILABLE_STATIC_INLINE_IN_2_60
408 static inline GRecMutexLocker *
409 g_rec_mutex_locker_new (GRecMutex *rec_mutex)
411 g_rec_mutex_lock (rec_mutex);
412 return (GRecMutexLocker *) rec_mutex;
414 G_GNUC_END_IGNORE_DEPRECATIONS
417 * g_rec_mutex_locker_free:
418 * @locker: a GRecMutexLocker
420 * Unlock @locker's recursive mutex. See g_rec_mutex_locker_new() for details.
422 * No memory is freed, it is equivalent to a g_rec_mutex_unlock() call.
426 G_GNUC_BEGIN_IGNORE_DEPRECATIONS
427 GLIB_AVAILABLE_STATIC_INLINE_IN_2_60
429 g_rec_mutex_locker_free (GRecMutexLocker *locker)
431 g_rec_mutex_unlock ((GRecMutex *) locker);
433 G_GNUC_END_IGNORE_DEPRECATIONS
436 * GRWLockWriterLocker:
438 * Opaque type. See g_rw_lock_writer_locker_new() for details.
441 typedef void GRWLockWriterLocker;
444 * g_rw_lock_writer_locker_new:
445 * @rw_lock: a #GRWLock
447 * Obtain a write lock on @rw_lock and return a new #GRWLockWriterLocker.
448 * Unlock with g_rw_lock_writer_locker_free(). Using g_rw_lock_writer_unlock()
449 * on @rw_lock while a #GRWLockWriterLocker exists can lead to undefined
452 * No allocation is performed, it is equivalent to a g_rw_lock_writer_lock() call.
454 * This is intended to be used with g_autoptr(). Note that g_autoptr()
455 * is only available when using GCC or clang, so the following example
456 * will only work with those compilers:
467 * my_object_get_data (MyObject *self, guint index)
469 * g_autoptr(GRWLockReaderLocker) locker = g_rw_lock_reader_locker_new (&self->rw_lock);
471 * // Code with a read lock obtained on rw_lock here
473 * if (self->array == NULL)
474 * // No need to unlock
477 * if (index < self->array->len)
478 * // No need to unlock
479 * return g_ptr_array_index (self->array, index);
481 * // Optionally early unlock
482 * g_clear_pointer (&locker, g_rw_lock_reader_locker_free);
484 * // Code with rw_lock unlocked here
489 * my_object_set_data (MyObject *self, guint index, gpointer data)
491 * g_autoptr(GRWLockWriterLocker) locker = g_rw_lock_writer_locker_new (&self->rw_lock);
493 * // Code with a write lock obtained on rw_lock here
495 * if (self->array == NULL)
496 * self->array = g_ptr_array_new ();
499 * // No need to unlock
502 * if (index >= self->array->len)
503 * g_ptr_array_set_size (self->array, index+1);
504 * g_ptr_array_index (self->array, index) = data;
506 * // Optionally early unlock
507 * g_clear_pointer (&locker, g_rw_lock_writer_locker_free);
509 * // Code with rw_lock unlocked here
513 * Returns: a #GRWLockWriterLocker
516 G_GNUC_BEGIN_IGNORE_DEPRECATIONS
517 GLIB_AVAILABLE_STATIC_INLINE_IN_2_62
518 static inline GRWLockWriterLocker *
519 g_rw_lock_writer_locker_new (GRWLock *rw_lock)
521 g_rw_lock_writer_lock (rw_lock);
522 return (GRWLockWriterLocker *) rw_lock;
524 G_GNUC_END_IGNORE_DEPRECATIONS
527 * g_rw_lock_writer_locker_free:
528 * @locker: a GRWLockWriterLocker
530 * Release a write lock on @locker's read-write lock. See
531 * g_rw_lock_writer_locker_new() for details.
533 * No memory is freed, it is equivalent to a g_rw_lock_writer_unlock() call.
537 G_GNUC_BEGIN_IGNORE_DEPRECATIONS
538 GLIB_AVAILABLE_STATIC_INLINE_IN_2_62
540 g_rw_lock_writer_locker_free (GRWLockWriterLocker *locker)
542 g_rw_lock_writer_unlock ((GRWLock *) locker);
544 G_GNUC_END_IGNORE_DEPRECATIONS
547 * GRWLockReaderLocker:
549 * Opaque type. See g_rw_lock_reader_locker_new() for details.
552 typedef void GRWLockReaderLocker;
555 * g_rw_lock_reader_locker_new:
556 * @rw_lock: a #GRWLock
558 * Obtain a read lock on @rw_lock and return a new #GRWLockReaderLocker.
559 * Unlock with g_rw_lock_reader_locker_free(). Using g_rw_lock_reader_unlock()
560 * on @rw_lock while a #GRWLockReaderLocker exists can lead to undefined
563 * No allocation is performed, it is equivalent to a g_rw_lock_reader_lock() call.
565 * This is intended to be used with g_autoptr(). For a code sample, see
566 * g_rw_lock_writer_locker_new().
568 * Returns: a #GRWLockReaderLocker
571 G_GNUC_BEGIN_IGNORE_DEPRECATIONS
572 GLIB_AVAILABLE_STATIC_INLINE_IN_2_62
573 static inline GRWLockReaderLocker *
574 g_rw_lock_reader_locker_new (GRWLock *rw_lock)
576 g_rw_lock_reader_lock (rw_lock);
577 return (GRWLockReaderLocker *) rw_lock;
579 G_GNUC_END_IGNORE_DEPRECATIONS
582 * g_rw_lock_reader_locker_free:
583 * @locker: a GRWLockReaderLocker
585 * Release a read lock on @locker's read-write lock. See
586 * g_rw_lock_reader_locker_new() for details.
588 * No memory is freed, it is equivalent to a g_rw_lock_reader_unlock() call.
592 G_GNUC_BEGIN_IGNORE_DEPRECATIONS
593 GLIB_AVAILABLE_STATIC_INLINE_IN_2_62
595 g_rw_lock_reader_locker_free (GRWLockReaderLocker *locker)
597 g_rw_lock_reader_unlock ((GRWLock *) locker);
599 G_GNUC_END_IGNORE_DEPRECATIONS
603 #endif /* __G_THREAD_H__ */