1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 02111-1307, USA.
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 #if defined(G_DISABLE_SINGLE_INCLUDES) && !defined (__G_LIB_H__) && !defined (GLIB_COMPILATION)
28 #error "Only <glib.h> can be included directly."
31 #ifndef __G_THREAD_H__
32 #define __G_THREAD_H__
34 #include <glib/gerror.h>
35 #include <glib/gtypes.h>
36 #include <glib/gutils.h> /* for G_INLINE_FUNC */
37 #include <glib/gatomic.h> /* for g_atomic_pointer_get */
41 /* GLib Thread support
44 extern GQuark g_thread_error_quark (void);
45 #define G_THREAD_ERROR g_thread_error_quark ()
49 G_THREAD_ERROR_AGAIN /* Resource temporarily unavailable */
52 typedef gpointer (*GThreadFunc) (gpointer data);
56 G_THREAD_PRIORITY_LOW,
57 G_THREAD_PRIORITY_NORMAL,
58 G_THREAD_PRIORITY_HIGH,
59 G_THREAD_PRIORITY_URGENT
62 typedef struct _GThread GThread;
69 GThreadPriority priority;
72 typedef struct _GMutex GMutex;
73 typedef struct _GCond GCond;
74 typedef struct _GPrivate GPrivate;
75 typedef struct _GStaticPrivate GStaticPrivate;
77 typedef struct _GThreadFunctions GThreadFunctions;
78 struct _GThreadFunctions
80 GMutex* (*mutex_new) (void);
81 void (*mutex_lock) (GMutex *mutex);
82 gboolean (*mutex_trylock) (GMutex *mutex);
83 void (*mutex_unlock) (GMutex *mutex);
84 void (*mutex_free) (GMutex *mutex);
85 GCond* (*cond_new) (void);
86 void (*cond_signal) (GCond *cond);
87 void (*cond_broadcast) (GCond *cond);
88 void (*cond_wait) (GCond *cond,
90 gboolean (*cond_timed_wait) (GCond *cond,
93 void (*cond_free) (GCond *cond);
94 GPrivate* (*private_new) (GDestroyNotify destructor);
95 gpointer (*private_get) (GPrivate *private_key);
96 void (*private_set) (GPrivate *private_key,
98 void (*thread_create) (GThreadFunc func,
103 GThreadPriority priority,
106 void (*thread_yield) (void);
107 void (*thread_join) (gpointer thread);
108 void (*thread_exit) (void);
109 void (*thread_set_priority)(gpointer thread,
110 GThreadPriority priority);
111 void (*thread_self) (gpointer thread);
112 gboolean (*thread_equal) (gpointer thread1,
116 GLIB_VAR GThreadFunctions g_thread_functions_for_glib_use;
117 GLIB_VAR gboolean g_thread_use_default_impl;
118 GLIB_VAR gboolean g_threads_got_initialized;
120 GLIB_VAR guint64 (*g_thread_gettime) (void);
122 /* initializes the mutex/cond/private implementation for glib, might
123 * only be called once, and must not be called directly or indirectly
124 * from another glib-function, e.g. as a callback.
126 void g_thread_init (GThreadFunctions *vtable);
128 /* Errorcheck mutexes. If you define G_ERRORCHECK_MUTEXES, then all
129 * mutexes will check for re-locking and re-unlocking */
131 /* Initialize thread system with errorcheck mutexes. vtable must be
132 * NULL. Do not call directly. Use #define G_ERRORCHECK_MUTEXES
135 void g_thread_init_with_errorcheck_mutexes (GThreadFunctions* vtable);
137 /* A random number to recognize debug calls to g_mutex_... */
138 #define G_MUTEX_DEBUG_MAGIC 0xf8e18ad7
140 #ifdef G_ERRORCHECK_MUTEXES
141 #define g_thread_init(vtable) g_thread_init_with_errorcheck_mutexes (vtable)
144 /* internal function for fallback static mutex implementation */
145 GMutex* g_static_mutex_get_mutex_impl (GMutex **mutex);
148 #define g_static_mutex_get_mutex_impl_shortcut(mutex) \
149 (g_atomic_pointer_get ((gpointer*)(void*)mutex) ? *(mutex) : \
150 g_static_mutex_get_mutex_impl (mutex))
152 #define g_static_mutex_get_mutex_impl_shortcut(mutex) \
153 (g_atomic_pointer_get (mutex) ? *(mutex) : \
154 g_static_mutex_get_mutex_impl (mutex))
157 /* shorthands for conditional and unconditional function calls */
159 #define G_THREAD_UF(op, arglist) \
160 (*g_thread_functions_for_glib_use . op) arglist
161 #define G_THREAD_CF(op, fail, arg) \
162 (g_thread_supported () ? G_THREAD_UF (op, arg) : (fail))
163 #define G_THREAD_ECF(op, fail, mutex, type) \
164 (g_thread_supported () ? \
165 ((type(*)(GMutex*, const gulong, gchar const*)) \
166 (*g_thread_functions_for_glib_use . op)) \
167 (mutex, G_MUTEX_DEBUG_MAGIC, G_STRLOC) : (fail))
169 #ifndef G_ERRORCHECK_MUTEXES
170 # define g_mutex_lock(mutex) \
171 G_THREAD_CF (mutex_lock, (void)0, (mutex))
172 # define g_mutex_trylock(mutex) \
173 G_THREAD_CF (mutex_trylock, TRUE, (mutex))
174 # define g_mutex_unlock(mutex) \
175 G_THREAD_CF (mutex_unlock, (void)0, (mutex))
176 # define g_mutex_free(mutex) \
177 G_THREAD_CF (mutex_free, (void)0, (mutex))
178 # define g_cond_wait(cond, mutex) \
179 G_THREAD_CF (cond_wait, (void)0, (cond, mutex))
180 # define g_cond_timed_wait(cond, mutex, abs_time) \
181 G_THREAD_CF (cond_timed_wait, TRUE, (cond, mutex, abs_time))
182 #else /* G_ERRORCHECK_MUTEXES */
183 # define g_mutex_lock(mutex) \
184 G_THREAD_ECF (mutex_lock, (void)0, (mutex), void)
185 # define g_mutex_trylock(mutex) \
186 G_THREAD_ECF (mutex_trylock, TRUE, (mutex), gboolean)
187 # define g_mutex_unlock(mutex) \
188 G_THREAD_ECF (mutex_unlock, (void)0, (mutex), void)
189 # define g_mutex_free(mutex) \
190 G_THREAD_ECF (mutex_free, (void)0, (mutex), void)
191 # define g_cond_wait(cond, mutex) \
192 (g_thread_supported () ? ((void(*)(GCond*, GMutex*, gulong, gchar*))\
193 g_thread_functions_for_glib_use.cond_wait) \
194 (cond, mutex, G_MUTEX_DEBUG_MAGIC, G_STRLOC) : (void) 0)
195 # define g_cond_timed_wait(cond, mutex, abs_time) \
196 (g_thread_supported () ? \
197 ((gboolean(*)(GCond*, GMutex*, GTimeVal*, gulong, gchar*)) \
198 g_thread_functions_for_glib_use.cond_timed_wait) \
199 (cond, mutex, abs_time, G_MUTEX_DEBUG_MAGIC, G_STRLOC) : TRUE)
200 #endif /* G_ERRORCHECK_MUTEXES */
202 #define g_thread_supported() (g_threads_got_initialized)
203 #define g_mutex_new() G_THREAD_UF (mutex_new, ())
204 #define g_cond_new() G_THREAD_UF (cond_new, ())
205 #define g_cond_signal(cond) G_THREAD_CF (cond_signal, (void)0, (cond))
206 #define g_cond_broadcast(cond) G_THREAD_CF (cond_broadcast, (void)0, (cond))
207 #define g_cond_free(cond) G_THREAD_CF (cond_free, (void)0, (cond))
208 #define g_private_new(destructor) G_THREAD_UF (private_new, (destructor))
209 #define g_private_get(private_key) G_THREAD_CF (private_get, \
210 ((gpointer)private_key), \
212 #define g_private_set(private_key, value) G_THREAD_CF (private_set, \
213 (void) (private_key = \
214 (GPrivate*) (value)), \
215 (private_key, value))
216 #define g_thread_yield() G_THREAD_CF (thread_yield, (void)0, ())
218 #define g_thread_create(func, data, joinable, error) \
219 (g_thread_create_full (func, data, 0, joinable, FALSE, \
220 G_THREAD_PRIORITY_NORMAL, error))
222 GThread* g_thread_create_full (GThreadFunc func,
227 GThreadPriority priority,
229 GThread* g_thread_self (void);
230 void g_thread_exit (gpointer retval);
231 gpointer g_thread_join (GThread *thread);
233 void g_thread_set_priority (GThread *thread,
234 GThreadPriority priority);
236 /* GStaticMutexes can be statically initialized with the value
237 * G_STATIC_MUTEX_INIT, and then they can directly be used, that is
238 * much easier, than having to explicitly allocate the mutex before
241 #define g_static_mutex_lock(mutex) \
242 g_mutex_lock (g_static_mutex_get_mutex (mutex))
243 #define g_static_mutex_trylock(mutex) \
244 g_mutex_trylock (g_static_mutex_get_mutex (mutex))
245 #define g_static_mutex_unlock(mutex) \
246 g_mutex_unlock (g_static_mutex_get_mutex (mutex))
247 void g_static_mutex_init (GStaticMutex *mutex);
248 void g_static_mutex_free (GStaticMutex *mutex);
250 struct _GStaticPrivate
255 #define G_STATIC_PRIVATE_INIT { 0 }
256 void g_static_private_init (GStaticPrivate *private_key);
257 gpointer g_static_private_get (GStaticPrivate *private_key);
258 void g_static_private_set (GStaticPrivate *private_key,
260 GDestroyNotify notify);
261 void g_static_private_free (GStaticPrivate *private_key);
263 typedef struct _GStaticRecMutex GStaticRecMutex;
264 struct _GStaticRecMutex
272 #define G_STATIC_REC_MUTEX_INIT { G_STATIC_MUTEX_INIT }
273 void g_static_rec_mutex_init (GStaticRecMutex *mutex);
274 void g_static_rec_mutex_lock (GStaticRecMutex *mutex);
275 gboolean g_static_rec_mutex_trylock (GStaticRecMutex *mutex);
276 void g_static_rec_mutex_unlock (GStaticRecMutex *mutex);
277 void g_static_rec_mutex_lock_full (GStaticRecMutex *mutex,
279 guint g_static_rec_mutex_unlock_full (GStaticRecMutex *mutex);
280 void g_static_rec_mutex_free (GStaticRecMutex *mutex);
282 typedef struct _GStaticRWLock GStaticRWLock;
283 struct _GStaticRWLock
290 gboolean have_writer;
295 #define G_STATIC_RW_LOCK_INIT { G_STATIC_MUTEX_INIT, NULL, NULL, 0, FALSE, 0, 0 }
297 void g_static_rw_lock_init (GStaticRWLock* lock);
298 void g_static_rw_lock_reader_lock (GStaticRWLock* lock);
299 gboolean g_static_rw_lock_reader_trylock (GStaticRWLock* lock);
300 void g_static_rw_lock_reader_unlock (GStaticRWLock* lock);
301 void g_static_rw_lock_writer_lock (GStaticRWLock* lock);
302 gboolean g_static_rw_lock_writer_trylock (GStaticRWLock* lock);
303 void g_static_rw_lock_writer_unlock (GStaticRWLock* lock);
304 void g_static_rw_lock_free (GStaticRWLock* lock);
306 void g_thread_foreach (GFunc thread_func,
311 G_ONCE_STATUS_NOTCALLED,
312 G_ONCE_STATUS_PROGRESS,
316 typedef struct _GOnce GOnce;
319 volatile GOnceStatus status;
320 volatile gpointer retval;
323 #define G_ONCE_INIT { G_ONCE_STATUS_NOTCALLED, NULL }
325 gpointer g_once_impl (GOnce *once, GThreadFunc func, gpointer arg);
327 #ifdef G_ATOMIC_OP_MEMORY_BARRIER_NEEDED
328 # define g_once(once, func, arg) g_once_impl ((once), (func), (arg))
329 #else /* !G_ATOMIC_OP_MEMORY_BARRIER_NEEDED*/
330 # define g_once(once, func, arg) \
331 (((once)->status == G_ONCE_STATUS_READY) ? \
333 g_once_impl ((once), (func), (arg)))
334 #endif /* G_ATOMIC_OP_MEMORY_BARRIER_NEEDED */
336 /* initialize-once guards, keyed by value_location */
337 G_INLINE_FUNC gboolean g_once_init_enter (volatile gsize *value_location);
338 gboolean g_once_init_enter_impl (volatile gsize *value_location);
339 void g_once_init_leave (volatile gsize *value_location,
340 gsize initialization_value);
341 #if defined (G_CAN_INLINE) || defined (__G_THREAD_C__)
342 G_INLINE_FUNC gboolean
343 g_once_init_enter (volatile gsize *value_location)
345 if G_LIKELY (g_atomic_pointer_get ((void*volatile*) value_location) != NULL)
348 return g_once_init_enter_impl (value_location);
350 #endif /* G_CAN_INLINE || __G_THREAD_C__ */
352 /* these are some convenience macros that expand to nothing if GLib
353 * was configured with --disable-threads. for using StaticMutexes,
354 * you define them with G_LOCK_DEFINE_STATIC (name) or G_LOCK_DEFINE (name)
355 * if you need to export the mutex. With G_LOCK_EXTERN (name) you can
356 * declare such an globally defined lock. name is a unique identifier
357 * for the protected varibale or code portion. locking, testing and
358 * unlocking of such mutexes can be done with G_LOCK(), G_UNLOCK() and
359 * G_TRYLOCK() respectively.
361 extern void glib_dummy_decl (void);
362 #define G_LOCK_NAME(name) g__ ## name ## _lock
363 #ifdef G_THREADS_ENABLED
364 # define G_LOCK_DEFINE_STATIC(name) static G_LOCK_DEFINE (name)
365 # define G_LOCK_DEFINE(name) \
366 GStaticMutex G_LOCK_NAME (name) = G_STATIC_MUTEX_INIT
367 # define G_LOCK_EXTERN(name) extern GStaticMutex G_LOCK_NAME (name)
369 # ifdef G_DEBUG_LOCKS
370 # define G_LOCK(name) G_STMT_START{ \
371 g_log (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG, \
372 "file %s: line %d (%s): locking: %s ", \
373 __FILE__, __LINE__, G_STRFUNC, \
375 g_static_mutex_lock (&G_LOCK_NAME (name)); \
377 # define G_UNLOCK(name) G_STMT_START{ \
378 g_log (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG, \
379 "file %s: line %d (%s): unlocking: %s ", \
380 __FILE__, __LINE__, G_STRFUNC, \
382 g_static_mutex_unlock (&G_LOCK_NAME (name)); \
384 # define G_TRYLOCK(name) \
385 (g_log (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG, \
386 "file %s: line %d (%s): try locking: %s ", \
387 __FILE__, __LINE__, G_STRFUNC, \
388 #name), g_static_mutex_trylock (&G_LOCK_NAME (name)))
389 # else /* !G_DEBUG_LOCKS */
390 # define G_LOCK(name) g_static_mutex_lock (&G_LOCK_NAME (name))
391 # define G_UNLOCK(name) g_static_mutex_unlock (&G_LOCK_NAME (name))
392 # define G_TRYLOCK(name) g_static_mutex_trylock (&G_LOCK_NAME (name))
393 # endif /* !G_DEBUG_LOCKS */
394 #else /* !G_THREADS_ENABLED */
395 # define G_LOCK_DEFINE_STATIC(name) extern void glib_dummy_decl (void)
396 # define G_LOCK_DEFINE(name) extern void glib_dummy_decl (void)
397 # define G_LOCK_EXTERN(name) extern void glib_dummy_decl (void)
398 # define G_LOCK(name)
399 # define G_UNLOCK(name)
400 # define G_TRYLOCK(name) (TRUE)
401 #endif /* !G_THREADS_ENABLED */
405 #endif /* __G_THREAD_H__ */