1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * gthread.c: posix thread system implementation
5 * Copyright 1998 Sebastian Wilhelmi; University of Karlsruhe
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
24 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
25 * file for a list of people on the GLib Team. See the ChangeLog
26 * files for a list of changes. These files are distributed with
27 * GLib at ftp://ftp.gtk.org/pub/gtk/.
30 /* The GMutex, GCond and GPrivate implementations in this file are some
31 * of the lowest-level code in GLib. All other parts of GLib (messages,
32 * memory, slices, etc) assume that they can freely use these facilities
33 * without risking recursion.
35 * As such, these functions are NOT permitted to call any other part of
38 * The thread manipulation functions (create, exit, join, etc.) have
39 * more freedom -- they can do as they please.
46 #include "gthreadprivate.h"
48 #include "gmessages.h"
49 #include "gstrfuncs.h"
57 #ifdef HAVE_SYS_TIME_H
58 # include <sys/time.h>
66 #ifdef HAVE_SYS_PRCTL_H
67 #include <sys/prctl.h>
71 g_thread_abort (gint status,
72 const gchar *function)
74 fprintf (stderr, "GLib (gthread-posix.c): Unexpected error from C library during '%s': %s. Aborting.\n",
75 strerror (status), function);
81 static pthread_mutex_t *
82 g_mutex_impl_new (void)
84 pthread_mutexattr_t *pattr = NULL;
85 pthread_mutex_t *mutex;
88 mutex = malloc (sizeof (pthread_mutex_t));
89 if G_UNLIKELY (mutex == NULL)
90 g_thread_abort (errno, "malloc");
92 #ifdef PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP
93 pthread_mutexattr_t attr;
94 pthread_mutexattr_init (&attr);
95 pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_ADAPTIVE_NP);
99 if G_UNLIKELY ((status = pthread_mutex_init (mutex, pattr)) != 0)
100 g_thread_abort (status, "pthread_mutex_init");
102 #ifdef PTHREAD_ADAPTIVE_MUTEX_NP
103 pthread_mutexattr_destroy (&attr);
110 g_mutex_impl_free (pthread_mutex_t *mutex)
112 pthread_mutex_destroy (mutex);
116 static pthread_mutex_t *
117 g_mutex_get_impl (GMutex *mutex)
119 pthread_mutex_t *impl = mutex->p;
121 if G_UNLIKELY (impl == NULL)
123 impl = g_mutex_impl_new ();
124 if (!g_atomic_pointer_compare_and_exchange (&mutex->p, NULL, impl))
125 g_mutex_impl_free (impl);
135 * @mutex: an uninitialized #GMutex
137 * Initializes a #GMutex so that it can be used.
139 * This function is useful to initialize a mutex that has been
140 * allocated on the stack, or as part of a larger structure.
141 * It is not necessary to initialize a mutex that has been
142 * created that has been statically allocated.
152 * b = g_new (Blob, 1);
153 * g_mutex_init (&b->m);
156 * To undo the effect of g_mutex_init() when a mutex is no longer
157 * needed, use g_mutex_clear().
159 * Calling g_mutex_init() on an already initialized #GMutex leads
160 * to undefined behaviour.
165 g_mutex_init (GMutex *mutex)
167 mutex->p = g_mutex_impl_new ();
172 * @mutex: an initialized #GMutex
174 * Frees the resources allocated to a mutex with g_mutex_init().
176 * This function should not be used with a #GMutex that has been
177 * statically allocated.
179 * Calling g_mutex_clear() on a locked mutex leads to undefined
185 g_mutex_clear (GMutex *mutex)
187 g_mutex_impl_free (mutex->p);
194 * Locks @mutex. If @mutex is already locked by another thread, the
195 * current thread will block until @mutex is unlocked by the other
198 * This function can be used even if g_thread_init() has not yet been
199 * called, and, in that case, will do nothing.
201 * <note>#GMutex is neither guaranteed to be recursive nor to be
202 * non-recursive. As such, calling g_mutex_lock() on a #GMutex that has
203 * already been locked by the same thread results in undefined behaviour
204 * (including but not limited to deadlocks).</note>
207 g_mutex_lock (GMutex *mutex)
211 if G_UNLIKELY ((status = pthread_mutex_lock (g_mutex_get_impl (mutex))) != 0)
212 g_thread_abort (status, "pthread_mutex_lock");
219 * Unlocks @mutex. If another thread is blocked in a g_mutex_lock()
220 * call for @mutex, it will become unblocked and can lock @mutex itself.
222 * Calling g_mutex_unlock() on a mutex that is not locked by the
223 * current thread leads to undefined behaviour.
225 * This function can be used even if g_thread_init() has not yet been
226 * called, and, in that case, will do nothing.
229 g_mutex_unlock (GMutex *mutex)
233 if G_UNLIKELY ((status = pthread_mutex_unlock (g_mutex_get_impl (mutex))) != 0)
234 g_thread_abort (status, "pthread_mutex_lock");
241 * Tries to lock @mutex. If @mutex is already locked by another thread,
242 * it immediately returns %FALSE. Otherwise it locks @mutex and returns
245 * This function can be used even if g_thread_init() has not yet been
246 * called, and, in that case, will immediately return %TRUE.
248 * <note>#GMutex is neither guaranteed to be recursive nor to be
249 * non-recursive. As such, calling g_mutex_lock() on a #GMutex that has
250 * already been locked by the same thread results in undefined behaviour
251 * (including but not limited to deadlocks or arbitrary return values).
254 * Returns: %TRUE if @mutex could be locked
257 g_mutex_trylock (GMutex *mutex)
261 if G_LIKELY ((status = pthread_mutex_trylock (g_mutex_get_impl (mutex))) == 0)
264 if G_UNLIKELY (status != EBUSY)
265 g_thread_abort (status, "pthread_mutex_trylock");
272 static pthread_mutex_t *
273 g_rec_mutex_impl_new (void)
275 pthread_mutexattr_t attr;
276 pthread_mutex_t *mutex;
278 mutex = g_slice_new (pthread_mutex_t);
279 pthread_mutexattr_init (&attr);
280 pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_RECURSIVE);
281 pthread_mutex_init (mutex, &attr);
282 pthread_mutexattr_destroy (&attr);
288 g_rec_mutex_impl_free (pthread_mutex_t *mutex)
290 pthread_mutex_destroy (mutex);
291 g_slice_free (pthread_mutex_t, mutex);
294 static pthread_mutex_t *
295 g_rec_mutex_get_impl (GRecMutex *rec_mutex)
297 pthread_mutex_t *impl = rec_mutex->p;
299 if G_UNLIKELY (impl == NULL)
301 impl = g_rec_mutex_impl_new ();
302 if (!g_atomic_pointer_compare_and_exchange (&rec_mutex->p, NULL, impl))
303 g_rec_mutex_impl_free (impl);
312 * @rec_mutex: an uninitialized #GRecMutex
314 * Initializes a #GRecMutex so that it can be used.
316 * This function is useful to initialize a recursive mutex
317 * that has been allocated on the stack, or as part of a larger
320 * It is not necessary to initialise a recursive mutex that has been
321 * statically allocated.
331 * b = g_new (Blob, 1);
332 * g_rec_mutex_init (&b->m);
335 * Calling g_rec_mutex_init() on an already initialized #GRecMutex
336 * leads to undefined behaviour.
338 * To undo the effect of g_rec_mutex_init() when a recursive mutex
339 * is no longer needed, use g_rec_mutex_clear().
344 g_rec_mutex_init (GRecMutex *rec_mutex)
346 rec_mutex->p = g_rec_mutex_impl_new ();
351 * @rec_mutex: an initialized #GRecMutex
353 * Frees the resources allocated to a recursive mutex with
354 * g_rec_mutex_init().
356 * This function should not be used with a #GRecMutex that has been
357 * statically allocated.
359 * Calling g_rec_mutex_clear() on a locked recursive mutex leads
360 * to undefined behaviour.
365 g_rec_mutex_clear (GRecMutex *rec_mutex)
367 g_rec_mutex_impl_free (rec_mutex->p);
372 * @rec_mutex: a #GRecMutex
374 * Locks @rec_mutex. If @rec_mutex is already locked by another
375 * thread, the current thread will block until @rec_mutex is
376 * unlocked by the other thread. If @rec_mutex is already locked
377 * by the current thread, the 'lock count' of @rec_mutex is increased.
378 * The mutex will only become available again when it is unlocked
379 * as many times as it has been locked.
384 g_rec_mutex_lock (GRecMutex *mutex)
386 pthread_mutex_lock (g_rec_mutex_get_impl (mutex));
390 * g_rec_mutex_unlock:
391 * @rec_mutex: a #GRecMutex
393 * Unlocks @rec_mutex. If another thread is blocked in a
394 * g_rec_mutex_lock() call for @rec_mutex, it will become unblocked
395 * and can lock @rec_mutex itself.
397 * Calling g_rec_mutex_unlock() on a recursive mutex that is not
398 * locked by the current thread leads to undefined behaviour.
403 g_rec_mutex_unlock (GRecMutex *rec_mutex)
405 pthread_mutex_unlock (rec_mutex->p);
409 * g_rec_mutex_trylock:
410 * @rec_mutex: a #GRecMutex
412 * Tries to lock @rec_mutex. If @rec_mutex is already locked
413 * by another thread, it immediately returns %FALSE. Otherwise
414 * it locks @rec_mutex and returns %TRUE.
416 * Returns: %TRUE if @rec_mutex could be locked
421 g_rec_mutex_trylock (GRecMutex *rec_mutex)
423 if (pthread_mutex_trylock (g_rec_mutex_get_impl (rec_mutex)) != 0)
431 static pthread_rwlock_t *
432 g_rw_lock_impl_new (void)
434 pthread_rwlock_t *rwlock;
437 rwlock = malloc (sizeof (pthread_rwlock_t));
438 if G_UNLIKELY (rwlock == NULL)
439 g_thread_abort (errno, "malloc");
441 if G_UNLIKELY ((status = pthread_rwlock_init (rwlock, NULL)) != 0)
442 g_thread_abort (status, "pthread_rwlock_init");
448 g_rw_lock_impl_free (pthread_rwlock_t *rwlock)
450 pthread_rwlock_destroy (rwlock);
454 static pthread_rwlock_t *
455 g_rw_lock_get_impl (GRWLock *lock)
457 pthread_rwlock_t *impl = lock->p;
459 if G_UNLIKELY (impl == NULL)
461 impl = g_rw_lock_impl_new ();
462 if (!g_atomic_pointer_compare_and_exchange (&lock->p, NULL, impl))
463 g_rw_lock_impl_free (impl);
472 * @rw_lock: an uninitialized #GRWLock
474 * Initializes a #GRWLock so that it can be used.
476 * This function is useful to initialize a lock that has been
477 * allocated on the stack, or as part of a larger structure. It is not
478 * necessary to initialise a reader-writer lock that has been statically
489 * b = g_new (Blob, 1);
490 * g_rw_lock_init (&b->l);
493 * To undo the effect of g_rw_lock_init() when a lock is no longer
494 * needed, use g_rw_lock_clear().
496 * Calling g_rw_lock_init() on an already initialized #GRWLock leads
497 * to undefined behaviour.
502 g_rw_lock_init (GRWLock *rw_lock)
504 rw_lock->p = g_rw_lock_impl_new ();
509 * @rw_lock: an initialized #GRWLock
511 * Frees the resources allocated to a lock with g_rw_lock_init().
513 * This function should not be used with a #GRWLock that has been
514 * statically allocated.
516 * Calling g_rw_lock_clear() when any thread holds the lock
517 * leads to undefined behaviour.
522 g_rw_lock_clear (GRWLock *rw_lock)
524 g_rw_lock_impl_free (rw_lock->p);
528 * g_rw_lock_writer_lock:
529 * @rw_lock: a #GRWLock
531 * Obtain a write lock on @rw_lock. If any thread already holds
532 * a read or write lock on @rw_lock, the current thread will block
533 * until all other threads have dropped their locks on @rw_lock.
538 g_rw_lock_writer_lock (GRWLock *rw_lock)
540 pthread_rwlock_wrlock (g_rw_lock_get_impl (rw_lock));
544 * g_rw_lock_writer_trylock:
545 * @rw_lock: a #GRWLock
547 * Tries to obtain a write lock on @rw_lock. If any other thread holds
548 * a read or write lock on @rw_lock, it immediately returns %FALSE.
549 * Otherwise it locks @rw_lock and returns %TRUE.
551 * Returns: %TRUE if @rw_lock could be locked
556 g_rw_lock_writer_trylock (GRWLock *rw_lock)
558 if (pthread_rwlock_trywrlock (g_rw_lock_get_impl (rw_lock)) != 0)
565 * g_rw_lock_writer_unlock:
566 * @rw_lock: a #GRWLock
568 * Release a write lock on @rw_lock.
570 * Calling g_rw_lock_writer_unlock() on a lock that is not held
571 * by the current thread leads to undefined behaviour.
576 g_rw_lock_writer_unlock (GRWLock *rw_lock)
578 pthread_rwlock_unlock (g_rw_lock_get_impl (rw_lock));
582 * g_rw_lock_reader_lock:
583 * @rw_lock: a #GRWLock
585 * Obtain a read lock on @rw_lock. If another thread currently holds
586 * the write lock on @rw_lock or blocks waiting for it, the current
587 * thread will block. Read locks can be taken recursively.
589 * It is implementation-defined how many threads are allowed to
590 * hold read locks on the same lock simultaneously.
595 g_rw_lock_reader_lock (GRWLock *rw_lock)
597 pthread_rwlock_rdlock (g_rw_lock_get_impl (rw_lock));
601 * g_rw_lock_reader_trylock:
602 * @rw_lock: a #GRWLock
604 * Tries to obtain a read lock on @rw_lock and returns %TRUE if
605 * the read lock was successfully obtained. Otherwise it
608 * Returns: %TRUE if @rw_lock could be locked
613 g_rw_lock_reader_trylock (GRWLock *rw_lock)
615 if (pthread_rwlock_tryrdlock (g_rw_lock_get_impl (rw_lock)) != 0)
622 * g_rw_lock_reader_unlock:
623 * @rw_lock: a #GRWLock
625 * Release a read lock on @rw_lock.
627 * Calling g_rw_lock_reader_unlock() on a lock that is not held
628 * by the current thread leads to undefined behaviour.
633 g_rw_lock_reader_unlock (GRWLock *rw_lock)
635 pthread_rwlock_unlock (g_rw_lock_get_impl (rw_lock));
640 static pthread_cond_t *
641 g_cond_impl_new (void)
643 pthread_condattr_t attr;
644 pthread_cond_t *cond;
647 pthread_condattr_init (&attr);
648 #ifdef CLOCK_MONOTONIC
649 pthread_condattr_setclock (&attr, CLOCK_MONOTONIC);
652 cond = malloc (sizeof (pthread_cond_t));
653 if G_UNLIKELY (cond == NULL)
654 g_thread_abort (errno, "malloc");
656 if G_UNLIKELY ((status = pthread_cond_init (cond, &attr)) != 0)
657 g_thread_abort (status, "pthread_cond_init");
659 pthread_condattr_destroy (&attr);
665 g_cond_impl_free (pthread_cond_t *cond)
667 pthread_cond_destroy (cond);
671 static pthread_cond_t *
672 g_cond_get_impl (GCond *cond)
674 pthread_cond_t *impl = cond->p;
676 if G_UNLIKELY (impl == NULL)
678 impl = g_cond_impl_new ();
679 if (!g_atomic_pointer_compare_and_exchange (&cond->p, NULL, impl))
680 g_cond_impl_free (impl);
689 * @cond: an uninitialized #GCond
691 * Initialises a #GCond so that it can be used.
693 * This function is useful to initialise a #GCond that has been
694 * allocated as part of a larger structure. It is not necessary to
695 * initialise a #GCond that has been statically allocated.
697 * To undo the effect of g_cond_init() when a #GCond is no longer
698 * needed, use g_cond_clear().
700 * Calling g_cond_init() on an already-initialised #GCond leads
701 * to undefined behaviour.
706 g_cond_init (GCond *cond)
708 cond->p = g_cond_impl_new ();
713 * @cond: an initialised #GCond
715 * Frees the resources allocated to a #GCond with g_cond_init().
717 * This function should not be used with a #GCond that has been
718 * statically allocated.
720 * Calling g_cond_clear() for a #GCond on which threads are
721 * blocking leads to undefined behaviour.
726 g_cond_clear (GCond *cond)
728 g_cond_impl_free (cond->p);
734 * @mutex: a #GMutex that is currently locked
736 * Atomically releases @mutex and waits until @cond is signalled.
738 * When using condition variables, it is possible that a spurious wakeup
739 * may occur (ie: g_cond_wait() returns even though g_cond_signal() was
740 * not called). It's also possible that a stolen wakeup may occur.
741 * This is when g_cond_signal() is called, but another thread acquires
742 * @mutex before this thread and modifies the state of the program in
743 * such a way that when g_cond_wait() is able to return, the expected
744 * condition is no longer met.
746 * For this reason, g_cond_wait() must always be used in a loop. See
747 * the documentation for #GCond for a complete example.
750 g_cond_wait (GCond *cond,
755 if G_UNLIKELY ((status = pthread_cond_wait (g_cond_get_impl (cond), g_mutex_get_impl (mutex))) != 0)
756 g_thread_abort (status, "pthread_cond_wait");
763 * If threads are waiting for @cond, at least one of them is unblocked.
764 * If no threads are waiting for @cond, this function has no effect.
765 * It is good practice to hold the same lock as the waiting thread
766 * while calling this function, though not required.
768 * This function can be used even if g_thread_init() has not yet been
769 * called, and, in that case, will do nothing.
772 g_cond_signal (GCond *cond)
776 if G_UNLIKELY ((status = pthread_cond_signal (g_cond_get_impl (cond))) != 0)
777 g_thread_abort (status, "pthread_cond_signal");
784 * If threads are waiting for @cond, all of them are unblocked.
785 * If no threads are waiting for @cond, this function has no effect.
786 * It is good practice to lock the same mutex as the waiting threads
787 * while calling this function, though not required.
789 * This function can be used even if g_thread_init() has not yet been
790 * called, and, in that case, will do nothing.
793 g_cond_broadcast (GCond *cond)
797 if G_UNLIKELY ((status = pthread_cond_broadcast (g_cond_get_impl (cond))) != 0)
798 g_thread_abort (status, "pthread_cond_broadcast");
804 * @mutex: a #GMutex that is currently locked
805 * @end_time: the monotonic time to wait until
807 * Waits until either @cond is signalled or @end_time has passed.
809 * As with g_cond_wait() it is possible that a spurious or stolen wakeup
810 * could occur. For that reason, waiting on a condition variable should
811 * always be in a loop, based on an explicitly-checked predicate.
813 * %TRUE is returned if the condition variable was signalled (or in the
814 * case of a spurious wakeup). %FALSE is returned if @end_time has
817 * The following code shows how to correctly perform a timed wait on a
818 * condition variable (extended the example presented in the
819 * documentation for #GCond):
823 * pop_data_timed (void)
828 * g_mutex_lock (&data_mutex);
830 * end_time = g_get_monotonic_time () + 5 * G_TIME_SPAN_SECOND;
831 * while (!current_data)
832 * if (!g_cond_wait_until (&data_cond, &data_mutex, end_time))
834 * // timeout has passed.
835 * g_mutex_unlock (&data_mutex);
839 * // there is data for us
840 * data = current_data;
841 * current_data = NULL;
843 * g_mutex_unlock (&data_mutex);
849 * Notice that the end time is calculated once, before entering the
850 * loop and reused. This is the motivation behind the use of absolute
851 * time on this API -- if a relative time of 5 seconds were passed
852 * directly to the call and a spurious wakeup occured, the program would
853 * have to start over waiting again (which would lead to a total wait
854 * time of more than 5 seconds).
856 * Returns: %TRUE on a signal, %FALSE on a timeout
860 g_cond_wait_until (GCond *cond,
867 ts.tv_sec = end_time / 1000000;
868 ts.tv_nsec = (end_time % 1000000) * 1000;
870 if ((status = pthread_cond_timedwait (g_cond_get_impl (cond), g_mutex_get_impl (mutex), &ts)) == 0)
873 if G_UNLIKELY (status != ETIMEDOUT)
874 g_thread_abort (status, "pthread_cond_timedwait");
884 * The #GPrivate struct is an opaque data structure to represent a
885 * thread-local data key. It is approximately equivalent to the
886 * pthread_setspecific()/pthread_getspecific() APIs on POSIX and to
887 * TlsSetValue()/TlsGetValue() on Windows.
889 * If you don't already know why you might want this functionality,
890 * then you probably don't need it.
892 * #GPrivate is a very limited resource (as far as 128 per program,
893 * shared between all libraries). It is also not possible to destroy a
894 * #GPrivate after it has been used. As such, it is only ever acceptable
895 * to use #GPrivate in static scope, and even then sparingly so.
897 * See G_PRIVATE_INIT() for a couple of examples.
899 * The #GPrivate structure should be considered opaque. It should only
900 * be accessed via the <function>g_private_</function> functions.
905 * @notify: a #GDestroyNotify
907 * A macro to assist with the static initialisation of a #GPrivate.
909 * This macro is useful for the case that a #GDestroyNotify function
910 * should be associated the key. This is needed when the key will be
911 * used to point at memory that should be deallocated when the thread
914 * Additionally, the #GDestroyNotify will also be called on the previous
915 * value stored in the key when g_private_replace() is used.
917 * If no #GDestroyNotify is needed, then use of this macro is not
918 * required -- if the #GPrivate is declared in static scope then it will
919 * be properly initialised by default (ie: to all zeros). See the
923 * static GPrivate name_key = G_PRIVATE_INIT (g_free);
925 * // return value should not be freed
927 * get_local_name (void)
929 * return g_private_get (&name_key);
933 * set_local_name (const gchar *name)
935 * g_private_replace (&name_key, g_strdup (name));
939 * static GPrivate count_key; // no free function
942 * get_local_count (void)
944 * return GPOINTER_TO_INT (g_private_get (&count_key));
948 * set_local_count (gint count)
950 * g_private_set (&count_key, GINT_TO_POINTER (count));
957 static pthread_key_t *
958 g_private_impl_new (GDestroyNotify notify)
963 key = malloc (sizeof (pthread_key_t));
964 if G_UNLIKELY (key == NULL)
965 g_thread_abort (errno, "malloc");
966 status = pthread_key_create (key, notify);
967 if G_UNLIKELY (status != 0)
968 g_thread_abort (status, "pthread_key_create");
974 g_private_impl_free (pthread_key_t *key)
978 status = pthread_key_delete (*key);
979 if G_UNLIKELY (status != 0)
980 g_thread_abort (status, "pthread_key_delete");
984 static pthread_key_t *
985 g_private_get_impl (GPrivate *key)
987 pthread_key_t *impl = key->p;
989 if G_UNLIKELY (impl == NULL)
991 impl = g_private_impl_new (key->notify);
992 if (!g_atomic_pointer_compare_and_exchange (&key->p, NULL, impl))
994 g_private_impl_free (impl);
1006 * Returns the current value of the thread local variable @key.
1008 * If the value has not yet been set in this thread, %NULL is returned.
1009 * Values are never copied between threads (when a new thread is
1010 * created, for example).
1012 * Returns: the thread-local value
1015 g_private_get (GPrivate *key)
1017 /* quote POSIX: No errors are returned from pthread_getspecific(). */
1018 return pthread_getspecific (*g_private_get_impl (key));
1024 * @value: the new value
1026 * Sets the thread local variable @key to have the value @value in the
1029 * This function differs from g_private_replace() in the following way:
1030 * the #GDestroyNotify for @key is not called on the old value.
1033 g_private_set (GPrivate *key,
1038 if G_UNLIKELY ((status = pthread_setspecific (*g_private_get_impl (key), value)) != 0)
1039 g_thread_abort (status, "pthread_setspecific");
1043 * g_private_replace:
1045 * @value: the new value
1047 * Sets the thread local variable @key to have the value @value in the
1050 * This function differs from g_private_set() in the following way: if
1051 * the previous value was non-%NULL then the #GDestroyNotify handler for
1052 * @key is run on it.
1057 g_private_replace (GPrivate *key,
1060 pthread_key_t *impl = g_private_get_impl (key);
1064 old = pthread_getspecific (*impl);
1065 if (old && key->notify)
1068 if G_UNLIKELY ((status = pthread_setspecific (*impl, value)) != 0)
1069 g_thread_abort (status, "pthread_setspecific");
1074 #define posix_check_err(err, name) G_STMT_START{ \
1075 int error = (err); \
1077 g_error ("file %s: line %d (%s): error '%s' during '%s'", \
1078 __FILE__, __LINE__, G_STRFUNC, \
1079 g_strerror (error), name); \
1082 #define posix_check_cmd(cmd) posix_check_err (cmd, #cmd)
1088 pthread_t system_thread;
1094 g_system_thread_free (GRealThread *thread)
1096 GThreadPosix *pt = (GThreadPosix *) thread;
1099 pthread_detach (pt->system_thread);
1101 g_mutex_clear (&pt->lock);
1103 g_slice_free (GThreadPosix, pt);
1107 g_system_thread_new (GThreadFunc thread_func,
1111 GThreadPosix *thread;
1112 pthread_attr_t attr;
1115 thread = g_slice_new0 (GThreadPosix);
1117 posix_check_cmd (pthread_attr_init (&attr));
1119 #ifdef HAVE_PTHREAD_ATTR_SETSTACKSIZE
1122 #ifdef _SC_THREAD_STACK_MIN
1123 stack_size = MAX (sysconf (_SC_THREAD_STACK_MIN), stack_size);
1124 #endif /* _SC_THREAD_STACK_MIN */
1125 /* No error check here, because some systems can't do it and
1126 * we simply don't want threads to fail because of that. */
1127 pthread_attr_setstacksize (&attr, stack_size);
1129 #endif /* HAVE_PTHREAD_ATTR_SETSTACKSIZE */
1131 ret = pthread_create (&thread->system_thread, &attr, (void* (*)(void*))thread_func, thread);
1133 posix_check_cmd (pthread_attr_destroy (&attr));
1137 g_set_error (error, G_THREAD_ERROR, G_THREAD_ERROR_AGAIN,
1138 "Error creating thread: %s", g_strerror (ret));
1139 g_slice_free (GThreadPosix, thread);
1143 posix_check_err (ret, "pthread_create");
1145 g_mutex_init (&thread->lock);
1147 return (GRealThread *) thread;
1153 * Causes the calling thread to voluntarily relinquish the CPU, so
1154 * that other threads can run.
1156 * This function is often used as a method to make busy wait less evil.
1159 g_thread_yield (void)
1165 g_system_thread_wait (GRealThread *thread)
1167 GThreadPosix *pt = (GThreadPosix *) thread;
1169 g_mutex_lock (&pt->lock);
1173 posix_check_cmd (pthread_join (pt->system_thread, NULL));
1177 g_mutex_unlock (&pt->lock);
1181 g_system_thread_exit (void)
1183 pthread_exit (NULL);
1187 g_system_thread_set_name (const gchar *name)
1189 #ifdef HAVE_SYS_PRCTL_H
1190 prctl (PR_SET_NAME, name, 0, 0, 0, 0);
1195 /* vim:set foldmethod=marker: */