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--- Libc/Libc-262/pthreads/pthread_mutex.c
+++ Libc/Libc-320/pthreads/pthread_mutex.c
@@ -1,3 +1,27 @@
+/*
+ * Copyright (c) 2000-2003 Apple Computer, Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_HEADER_END@
+ */
/*
* Copyright 1996 1995 by Open Software Foundation, Inc. 1997 1996 1995 1994 1993 1992 1991
* All Rights Reserved
@@ -36,49 +60,65 @@
int
pthread_mutex_destroy(pthread_mutex_t *mutex)
{
- if (mutex->sig != _PTHREAD_MUTEX_SIG)
- return (EINVAL);
- if ((mutex->owner != (pthread_t)NULL) ||
- (mutex->busy != (pthread_cond_t *)NULL))
- return (EBUSY);
- mutex->sig = _PTHREAD_NO_SIG;
+ int res;
+
+ LOCK(mutex->lock);
+ if (mutex->sig == _PTHREAD_MUTEX_SIG)
+ {
+ if (mutex->owner == (pthread_t)NULL &&
+ mutex->busy == (pthread_cond_t *)NULL)
+ {
+ mutex->sig = _PTHREAD_NO_SIG;
+ res = ESUCCESS;
+ }
+ else
+ res = EBUSY;
+ }
+ else
+ res = EINVAL;
+ UNLOCK(mutex->lock);
+ return (res);
+}
+
+/*
+ * Initialize a mutex variable, possibly with additional attributes.
+ */
+static int
+_pthread_mutex_init(pthread_mutex_t *mutex, const pthread_mutexattr_t *attr)
+{
+ if (attr)
+ {
+ if (attr->sig != _PTHREAD_MUTEX_ATTR_SIG)
+ return (EINVAL);
+ mutex->prioceiling = attr->prioceiling;
+ mutex->protocol = attr->protocol;
+ mutex->type = attr->type;
+ } else {
+ mutex->prioceiling = _PTHREAD_DEFAULT_PRIOCEILING;
+ mutex->protocol = _PTHREAD_DEFAULT_PROTOCOL;
+ mutex->type = PTHREAD_MUTEX_DEFAULT;
+ }
+ mutex->lock_count = 0;
+ mutex->owner = (pthread_t)NULL;
+ mutex->next = (pthread_mutex_t *)NULL;
+ mutex->prev = (pthread_mutex_t *)NULL;
+ mutex->busy = (pthread_cond_t *)NULL;
+ mutex->waiters = 0;
+ mutex->sem = SEMAPHORE_NULL;
+ mutex->order = SEMAPHORE_NULL;
+ mutex->sig = _PTHREAD_MUTEX_SIG;
return (ESUCCESS);
}
/*
* Initialize a mutex variable, possibly with additional attributes.
+ * Public interface - so don't trust the lock - initialize it first.
*/
int
pthread_mutex_init(pthread_mutex_t *mutex, const pthread_mutexattr_t *attr)
{
- LOCK_INIT(mutex->lock);
- mutex->sig = _PTHREAD_MUTEX_SIG;
- if (attr)
- {
- if (attr->sig != _PTHREAD_MUTEX_ATTR_SIG)
- return (EINVAL);
- mutex->prioceiling = attr->prioceiling;
- mutex->protocol = attr->protocol;
- mutex->type = attr->type;
- if ((mutex->type == PTHREAD_MUTEX_DEFAULT) || (mutex->type == PTHREAD_MUTEX_NORMAL))
- mutex->def = 1;
- else
- mutex->def = 0;
- } else {
- mutex->prioceiling = _PTHREAD_DEFAULT_PRIOCEILING;
- mutex->protocol = _PTHREAD_DEFAULT_PROTOCOL;
- mutex->type = PTHREAD_MUTEX_DEFAULT;
- mutex->def = 1;
- }
- mutex->lock_count = 0;
- mutex->owner = (pthread_t)NULL;
- mutex->next = (pthread_mutex_t *)NULL;
- mutex->prev = (pthread_mutex_t *)NULL;
- mutex->busy = (pthread_cond_t *)NULL;
- mutex->waiters = 0;
- mutex->cond_lock = 0;
- mutex->sem = MACH_PORT_NULL;
- return (ESUCCESS);
+ LOCK_INIT(mutex->lock);
+ return (_pthread_mutex_init(mutex, attr));
}
/*
@@ -89,18 +129,19 @@
_pthread_mutex_add(pthread_mutex_t *mutex, pthread_t self)
{
pthread_mutex_t *m;
- if (self != (pthread_t)0) {
- if ((m = self->mutexes) != (pthread_mutex_t *)NULL)
+ if (self != (pthread_t)0)
+ {
+ if ((m = self->mutexes) != (pthread_mutex_t *)NULL)
{ /* Add to list */
- m->prev = mutex;
+ m->prev = mutex;
}
- mutex->next = m;
- mutex->prev = (pthread_mutex_t *)NULL;
- self->mutexes = mutex;
- }
-}
-
-static void
+ mutex->next = m;
+ mutex->prev = (pthread_mutex_t *)NULL;
+ self->mutexes = mutex;
+ }
+}
+
+__private_extern__ void
_pthread_mutex_remove(pthread_mutex_t *mutex, pthread_t self)
{
pthread_mutex_t *n, *prev;
@@ -113,9 +154,9 @@
prev->next = mutex->next;
} else
{ /* This is the first in the list */
- if (self != (pthread_t)0) {
- self->mutexes = n;
- }
+ if (self != (pthread_t)0) {
+ self->mutexes = n;
+ }
}
}
#endif
@@ -127,141 +168,170 @@
int
pthread_mutex_lock(pthread_mutex_t *mutex)
{
- kern_return_t kern_res;
- pthread_t self;
- int slowpath;
-
- if (mutex->sig == _PTHREAD_MUTEX_SIG_init)
- {
- int res;
- if (res = pthread_mutex_init(mutex, NULL))
- return (res);
- }
- if (mutex->sig != _PTHREAD_MUTEX_SIG)
- return (EINVAL); /* Not a mutex variable */
-
-#if !defined(DEBUG)
- if (mutex->def) {
- slowpath = 0;
- self = (pthread_t)0x12141968;
+ kern_return_t kern_res;
+ pthread_t self;
+ int sig = mutex->sig;
+
+ /* To provide backwards compat for apps using mutex incorrectly */
+ if ((sig != _PTHREAD_MUTEX_SIG) && (sig != _PTHREAD_MUTEX_SIG_init))
+ return(EINVAL);
+ LOCK(mutex->lock);
+ if (mutex->sig != _PTHREAD_MUTEX_SIG)
+ {
+ if (mutex->sig != _PTHREAD_MUTEX_SIG_init)
+ {
+ UNLOCK(mutex->lock);
+ return (EINVAL);
+ }
+ _pthread_mutex_init(mutex, NULL);
+ self = _PTHREAD_MUTEX_OWNER_SELF;
+ }
+ else if (mutex->type != PTHREAD_MUTEX_NORMAL)
+ {
+ self = pthread_self();
+ if (mutex->owner == self)
+ {
+ int res;
+
+ if (mutex->type == PTHREAD_MUTEX_RECURSIVE)
+ {
+ if (mutex->lock_count < USHRT_MAX)
+ {
+ mutex->lock_count++;
+ res = ESUCCESS;
+ } else
+ res = EAGAIN;
+ } else /* PTHREAD_MUTEX_ERRORCHECK */
+ res = EDEADLK;
+ UNLOCK(mutex->lock);
+ return (res);
+ }
} else
-#endif /* DEBUG */
- {
- slowpath = 1;
+ self = _PTHREAD_MUTEX_OWNER_SELF;
+
+ if (mutex->owner != (pthread_t)NULL) {
+ if (mutex->waiters || mutex->owner != _PTHREAD_MUTEX_OWNER_SWITCHING)
+ {
+ semaphore_t sem, order;
+
+ if (++mutex->waiters == 1)
+ {
+ mutex->sem = sem = new_sem_from_pool();
+ mutex->order = order = new_sem_from_pool();
+ }
+ else
+ {
+ sem = mutex->sem;
+ order = mutex->order;
+ do {
+ PTHREAD_MACH_CALL(semaphore_wait(order), kern_res);
+ } while (kern_res == KERN_ABORTED);
+ }
+ UNLOCK(mutex->lock);
+
+ PTHREAD_MACH_CALL(semaphore_wait_signal(sem, order), kern_res);
+ while (kern_res == KERN_ABORTED)
+ {
+ PTHREAD_MACH_CALL(semaphore_wait(sem), kern_res);
+ }
+
+ LOCK(mutex->lock);
+ if (--mutex->waiters == 0)
+ {
+ PTHREAD_MACH_CALL(semaphore_wait(order), kern_res);
+ mutex->sem = mutex->order = SEMAPHORE_NULL;
+ restore_sem_to_pool(order);
+ restore_sem_to_pool(sem);
+ }
+ }
+ else if (mutex->owner == _PTHREAD_MUTEX_OWNER_SWITCHING)
+ {
+ semaphore_t sem = mutex->sem;
+ do {
+ PTHREAD_MACH_CALL(semaphore_wait(sem), kern_res);
+ } while (kern_res == KERN_ABORTED);
+ mutex->sem = SEMAPHORE_NULL;
+ restore_sem_to_pool(sem);
+ }
+ }
+
+ mutex->lock_count = 1;
+ mutex->owner = self;
+#if defined(DEBUG)
+ _pthread_mutex_add(mutex, self);
+#endif
+ UNLOCK(mutex->lock);
+ return (ESUCCESS);
+}
+
+/*
+ * Attempt to lock a mutex, but don't block if this isn't possible.
+ */
+int
+pthread_mutex_trylock(pthread_mutex_t *mutex)
+{
+ kern_return_t kern_res;
+ pthread_t self;
+
+ LOCK(mutex->lock);
+ if (mutex->sig != _PTHREAD_MUTEX_SIG)
+ {
+ if (mutex->sig != _PTHREAD_MUTEX_SIG_init)
+ {
+ UNLOCK(mutex->lock);
+ return (EINVAL);
+ }
+ _pthread_mutex_init(mutex, NULL);
+ self = _PTHREAD_MUTEX_OWNER_SELF;
+ }
+ else if (mutex->type != PTHREAD_MUTEX_NORMAL)
+ {
self = pthread_self();
- }
-
- LOCK(mutex->lock);
-
- if (mutex->waiters || (mutex->owner != (pthread_t)NULL))
- {
- if(slowpath && (mutex->owner == self)) {
- if(mutex->type == PTHREAD_MUTEX_ERRORCHECK ) {
- UNLOCK(mutex->lock);
- return(EDEADLK);
- } else if (mutex->type == PTHREAD_MUTEX_RECURSIVE ) {
- if (mutex->lock_count >= USHRT_MAX){
- UNLOCK(mutex->lock);
- return(EAGAIN);
- }
- mutex->lock_count++;
- UNLOCK(mutex->lock);
- return(ESUCCESS);
- }
- }
- mutex->waiters++;
- if (mutex->sem == MACH_PORT_NULL) {
- mutex->sem = new_sem_from_pool();
- }
- UNLOCK(mutex->lock);
- do {
- PTHREAD_MACH_CALL(semaphore_wait(mutex->sem), kern_res);
- } while (kern_res == KERN_ABORTED);
- LOCK(mutex->lock);
- mutex->waiters--;
- if (mutex->waiters == 0) {
- restore_sem_to_pool(mutex->sem);
- mutex->sem = MACH_PORT_NULL;
- }
- if (mutex->cond_lock) {
- mutex->cond_lock = 0;
- }
- }
-#if defined(DEBUG)
- _pthread_mutex_add(mutex, self);
+ if (mutex->type == PTHREAD_MUTEX_RECURSIVE)
+ {
+ if (mutex->owner == self)
+ {
+ int res;
+
+ if (mutex->lock_count < USHRT_MAX)
+ {
+ mutex->lock_count++;
+ res = ESUCCESS;
+ } else
+ res = EAGAIN;
+ UNLOCK(mutex->lock);
+ return (res);
+ }
+ }
+ } else
+ self = _PTHREAD_MUTEX_OWNER_SELF;
+
+ if (mutex->owner != (pthread_t)NULL)
+ {
+ if (mutex->waiters || mutex->owner != _PTHREAD_MUTEX_OWNER_SWITCHING)
+ {
+ UNLOCK(mutex->lock);
+ return (EBUSY);
+ }
+ else if (mutex->owner == _PTHREAD_MUTEX_OWNER_SWITCHING)
+ {
+ semaphore_t sem = mutex->sem;
+
+ do {
+ PTHREAD_MACH_CALL(semaphore_wait(sem), kern_res);
+ } while (kern_res == KERN_ABORTED);
+ restore_sem_to_pool(sem);
+ mutex->sem = SEMAPHORE_NULL;
+ }
+ }
+
+ mutex->lock_count = 1;
+ mutex->owner = self;
+#if defined(DEBUG)
+ _pthread_mutex_add(mutex, self);
#endif
- mutex->owner = self;
- if (slowpath && (mutex->type == PTHREAD_MUTEX_RECURSIVE))
- mutex->lock_count = 1;
- UNLOCK(mutex->lock);
- return (ESUCCESS);
-}
-
-/*
- * Attempt to lock a mutex, but don't block if this isn't possible.
- */
-int
-pthread_mutex_trylock(pthread_mutex_t *mutex)
-{
- kern_return_t kern_res;
- pthread_t self;
- int slowpath;
-
- if (mutex->sig == _PTHREAD_MUTEX_SIG_init)
- {
- int res;
- if (res = pthread_mutex_init(mutex, NULL))
- return (res);
- }
- if (mutex->sig != _PTHREAD_MUTEX_SIG)
- return (EINVAL); /* Not a mutex variable */
-
-#if !defined(DEBUG)
- if (mutex->def) {
- slowpath = 0;
- self = (pthread_t)0x12141968;
- } else
-#endif /* DEBUG */
- {
- slowpath = 1;
- self = pthread_self();
- }
-
- if (!TRY_LOCK(mutex->lock)) {
- return (EBUSY);
- }
-
- if(slowpath && (mutex->owner == self) && (mutex->type == PTHREAD_MUTEX_RECURSIVE )) {
- if (mutex->lock_count >= USHRT_MAX) {
- UNLOCK(mutex->lock);
- return(EAGAIN);
- }
- mutex->lock_count++;
- UNLOCK(mutex->lock);
- return(ESUCCESS);
- }
-
- if (mutex->waiters ||
- ((mutex->owner != (pthread_t)NULL) && (mutex->cond_lock == 0)))
- {
- UNLOCK(mutex->lock);
- return (EBUSY);
- } else {
-#if defined(DEBUG)
- _pthread_mutex_add(mutex, self);
-#endif
- mutex->owner = (pthread_t)self;
- if (mutex->cond_lock) {
- PTHREAD_MACH_CALL(semaphore_wait(mutex->sem), kern_res);
- mutex->cond_lock = 0;
- restore_sem_to_pool(mutex->sem);
- mutex->sem = MACH_PORT_NULL;
- }
- if (slowpath && (mutex->type == PTHREAD_MUTEX_RECURSIVE))
- mutex->lock_count = 1;
- UNLOCK(mutex->lock);
- return (ESUCCESS);
- }
+ UNLOCK(mutex->lock);
+ return (ESUCCESS);
}
/*
@@ -271,67 +341,63 @@
int
pthread_mutex_unlock(pthread_mutex_t *mutex)
{
- kern_return_t kern_res;
- int waiters;
- pthread_t self;
- int slowpath;
-
- if (mutex->sig == _PTHREAD_MUTEX_SIG_init)
- {
- int res;
- if (res = pthread_mutex_init(mutex, NULL))
- return (res);
- }
- if (mutex->sig != _PTHREAD_MUTEX_SIG)
- return (EINVAL); /* Not a mutex variable */
+ kern_return_t kern_res;
+ int waiters;
+ int sig = mutex->sig;
+
+ /* To provide backwards compat for apps using mutex incorrectly */
+
+ if ((sig != _PTHREAD_MUTEX_SIG) && (sig != _PTHREAD_MUTEX_SIG_init))
+ return(EINVAL);
+ LOCK(mutex->lock);
+ if (mutex->sig != _PTHREAD_MUTEX_SIG)
+ {
+ if (mutex->sig != _PTHREAD_MUTEX_SIG_init)
+ {
+ UNLOCK(mutex->lock);
+ return (EINVAL); /* Not a mutex variable */
+ }
+ _pthread_mutex_init(mutex, NULL);
+ } else
#if !defined(DEBUG)
- if (mutex->def) {
- slowpath = 0;
- self = (pthread_t)0x12141968;
- } else
+ if (mutex->type != PTHREAD_MUTEX_NORMAL)
+#endif
+ {
+ pthread_t self = pthread_self();
+ if (mutex->owner != self)
+ {
+#if defined(DEBUG)
+ abort();
+#endif
+ UNLOCK(mutex->lock);
+ return EPERM;
+ } else if (mutex->type == PTHREAD_MUTEX_RECURSIVE &&
+ --mutex->lock_count)
+ {
+ UNLOCK(mutex->lock);
+ return ESUCCESS;
+ }
+ }
+
+ mutex->lock_count = 0;
+#if defined(DEBUG)
+ _pthread_mutex_remove(mutex, mutex->owner);
#endif /* DEBUG */
- {
- slowpath = 1;
- self = pthread_self();
- }
-
- LOCK(mutex->lock);
-
-#if defined(DEBUG)
- if (mutex->owner != self)
-#else
- if (slowpath
- && ((mutex->type == PTHREAD_MUTEX_ERRORCHECK )
- || (mutex->type == PTHREAD_MUTEX_RECURSIVE ))
- && (mutex->owner != self))
-#endif /* DEBUG */
- {
- UNLOCK(mutex->lock);
-#if defined(DEBUG)
- abort();
-#endif
- return(EPERM);
- }
-
- if (slowpath && (mutex->type == PTHREAD_MUTEX_RECURSIVE) && --mutex->lock_count) {
- UNLOCK(mutex->lock);
- return (ESUCCESS);
-
- } else {
-#if defined(DEBUG)
- _pthread_mutex_remove(mutex, mutex->owner);
-#endif /* DEBUG */
- waiters = mutex->waiters;
- mutex->owner = (pthread_t)NULL;
+
+ waiters = mutex->waiters;
+ if (waiters)
+ {
+ mutex->owner = _PTHREAD_MUTEX_OWNER_SWITCHING;
UNLOCK(mutex->lock);
- if (waiters)
- {
- PTHREAD_MACH_CALL(semaphore_signal(mutex->sem), kern_res);
- }
- return (ESUCCESS);
-
- }
+ PTHREAD_MACH_CALL(semaphore_signal(mutex->sem), kern_res);
+ }
+ else
+ {
+ mutex->owner = (pthread_t)NULL;
+ UNLOCK(mutex->lock);
+ }
+ return (ESUCCESS);
}
/*
@@ -342,14 +408,17 @@
pthread_mutex_getprioceiling(const pthread_mutex_t *mutex,
int *prioceiling)
{
+ int res;
+
+ LOCK(mutex->lock);
if (mutex->sig == _PTHREAD_MUTEX_SIG)
{
*prioceiling = mutex->prioceiling;
- return (ESUCCESS);
- } else
- {
- return (EINVAL); /* Not an initialized 'attribute' structure */
- }
+ res = ESUCCESS;
+ } else
+ res = EINVAL; /* Not an initialized 'attribute' structure */
+ UNLOCK(mutex->lock);
+ return (res);
}
/*
@@ -361,6 +430,9 @@
int prioceiling,
int *old_prioceiling)
{
+ int res;
+
+ LOCK(mutex->lock);
if (mutex->sig == _PTHREAD_MUTEX_SIG)
{
if ((prioceiling >= -999) ||
@@ -368,15 +440,13 @@
{
*old_prioceiling = mutex->prioceiling;
mutex->prioceiling = prioceiling;
- return (ESUCCESS);
+ res = ESUCCESS;
} else
- {
- return (EINVAL); /* Invalid parameter */
- }
- } else
- {
- return (EINVAL); /* Not an initialized 'attribute' structure */
- }
+ res = EINVAL; /* Invalid parameter */
+ } else
+ res = EINVAL; /* Not an initialized 'attribute' structure */
+ UNLOCK(mutex->lock);
+ return (res);
}
/*