summaryrefslogtreecommitdiff
path: root/lib/libpthread/pthread_cond.c
diff options
context:
space:
mode:
authorthorpej <thorpej@NetBSD.org>2003-01-18 10:32:11 +0000
committerthorpej <thorpej@NetBSD.org>2003-01-18 10:32:11 +0000
commitc62a74e6d5cfb2fb5034e98b983da7e2fc87709d (patch)
treef1281fd7111ddb57951e4472b342b53a2f56244a /lib/libpthread/pthread_cond.c
parentaf919042eceb8c19f42acd688efa8cf58168af5d (diff)
Merge the nathanw_sa branch.
Diffstat (limited to 'lib/libpthread/pthread_cond.c')
-rw-r--r--lib/libpthread/pthread_cond.c344
1 files changed, 344 insertions, 0 deletions
diff --git a/lib/libpthread/pthread_cond.c b/lib/libpthread/pthread_cond.c
new file mode 100644
index 00000000000..b75e8648a75
--- /dev/null
+++ b/lib/libpthread/pthread_cond.c
@@ -0,0 +1,344 @@
+/* $NetBSD: pthread_cond.c,v 1.2 2003/01/18 10:34:15 thorpej Exp $ */
+
+/*-
+ * Copyright (c) 2001 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Nathan J. Williams.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the NetBSD
+ * Foundation, Inc. and its contributors.
+ * 4. Neither the name of The NetBSD Foundation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <sys/cdefs.h>
+
+#include "pthread.h"
+#include "pthread_int.h"
+
+#undef PTHREAD_COND_DEBUG
+
+#ifdef PTHREAD_COND_DEBUG
+#define SDPRINTF(x) DPRINTF(x)
+#else
+#define SDPRINTF(x)
+#endif
+
+static void pthread_cond_wait__callback(void *);
+
+__strong_alias(__libc_cond_init,pthread_cond_init)
+__strong_alias(__libc_cond_signal,pthread_cond_signal)
+__strong_alias(__libc_cond_broadcast,pthread_cond_broadcast)
+__strong_alias(__libc_cond_wait,pthread_cond_wait)
+__strong_alias(__libc_cond_timedwait,pthread_cond_timedwait)
+__strong_alias(__libc_cond_destroy,pthread_cond_destroy)
+
+int
+pthread_cond_init(pthread_cond_t *cond, const pthread_condattr_t *attr)
+{
+
+#ifdef ERRORCHECK
+ if ((cond == NULL) ||
+ (attr && (attr->ptca_magic != _PT_CONDATTR_MAGIC)))
+ return EINVAL;
+#endif
+
+ cond->ptc_magic = _PT_COND_MAGIC;
+ pthread_lockinit(&cond->ptc_lock);
+ PTQ_INIT(&cond->ptc_waiters);
+ cond->ptc_mutex = NULL;
+
+ return 0;
+}
+
+
+int
+pthread_cond_destroy(pthread_cond_t *cond)
+{
+
+#ifdef ERRORCHECK
+ if ((cond == NULL) || (cond->ptc_magic != _PT_COND_MAGIC) ||
+ (cond->ptc_mutex != NULL) ||
+ (cond->ptc_lock != __SIMPLELOCK_UNLOCKED))
+ return EINVAL;
+#endif
+
+ cond->ptc_magic = _PT_COND_DEAD;
+
+ return 0;
+}
+
+
+int
+pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex)
+{
+ pthread_t self;
+#ifdef ERRORCHECK
+ if ((cond == NULL) || (cond->ptc_magic != _PT_COND_MAGIC) ||
+ (mutex == NULL) || (mutex->ptm_magic != _PT_MUTEX_MAGIC))
+ return EINVAL;
+#endif
+ self = pthread__self();
+ pthread_spinlock(self, &cond->ptc_lock);
+#ifdef ERRORCHECK
+ if (cond->ptc_mutex == NULL)
+ cond->ptc_mutex = mutex;
+ else {
+ if (cond->ptc_mutex != mutex) {
+ pthread_spinunlock(self, &cond->ptc_lock);
+ return EINVAL;
+ }
+ /* Check the mutex is actually locked */
+ if (mutex->ptm_lock != __SIMPLELOCK_LOCKED) {
+ pthread_spinunlock(self, &cond->ptc_lock);
+ return EPERM;
+ }
+ }
+#endif
+ SDPRINTF(("(cond wait %p) Waiting on %p, mutex %p\n",
+ self, cond, mutex));
+ pthread_spinlock(self, &self->pt_statelock);
+ if (self->pt_cancel) {
+ pthread_spinunlock(self, &self->pt_statelock);
+ pthread_spinunlock(self, &cond->ptc_lock);
+ pthread_exit(PTHREAD_CANCELED);
+ }
+ self->pt_state = PT_STATE_BLOCKED_QUEUE;
+ self->pt_sleepobj = cond;
+ self->pt_sleepq = &cond->ptc_waiters;
+ self->pt_sleeplock = &cond->ptc_lock;
+ pthread_spinunlock(self, &self->pt_statelock);
+
+ PTQ_INSERT_TAIL(&cond->ptc_waiters, self, pt_sleep);
+ pthread_mutex_unlock(mutex);
+
+ pthread__block(self, &cond->ptc_lock);
+ /* Spinlock is unlocked on return */
+ pthread_mutex_lock(mutex);
+ pthread__testcancel(self);
+ SDPRINTF(("(cond wait %p) Woke up on %p, mutex %p\n",
+ self, cond, mutex));
+
+ return 0;
+}
+
+
+struct pthread_cond__waitarg {
+ pthread_t ptw_thread;
+ pthread_cond_t *ptw_cond;
+};
+
+int
+pthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex,
+ const struct timespec *abstime)
+{
+ pthread_t self;
+ struct pthread_cond__waitarg wait;
+ struct pt_alarm_t alarm;
+ int retval;
+
+#ifdef ERRORCHECK
+ if ((cond == NULL) || (cond->ptc_magic != _PT_COND_MAGIC) ||
+ (mutex == NULL) || (mutex->ptm_magic != _PT_MUTEX_MAGIC))
+ return EINVAL;
+ if ((abstime == NULL) || (abstime->tv_sec < 0 ||
+ abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000))
+ return EINVAL;
+#endif
+ self = pthread__self();
+ pthread_spinlock(self, &cond->ptc_lock);
+#ifdef ERRORCHECK
+ if (cond->ptc_mutex == NULL)
+ cond->ptc_mutex = mutex;
+ else {
+ if (cond->ptc_mutex != mutex) {
+ pthread_spinunlock(self, &cond->ptc_lock);
+ return EINVAL;
+ }
+ /* Check the mutex is actually locked */
+ if (mutex->ptm_lock != __SIMPLELOCK_LOCKED) {
+ pthread_spinunlock(self, &cond->ptc_lock);
+ return EPERM;
+ }
+ }
+#endif
+ wait.ptw_thread = self;
+ wait.ptw_cond = cond;
+ retval = 0;
+ SDPRINTF(("(cond timed wait %p) Waiting on %p until %d.%06ld\n",
+ self, cond, abstime->tv_sec, abstime->tv_nsec/1000));
+
+ pthread_spinlock(self, &self->pt_statelock);
+ if (self->pt_cancel) {
+ pthread_spinunlock(self, &self->pt_statelock);
+ pthread_spinunlock(self, &cond->ptc_lock);
+ pthread_exit(PTHREAD_CANCELED);
+ }
+ pthread__alarm_add(self, &alarm, abstime, pthread_cond_wait__callback,
+ &wait);
+ self->pt_state = PT_STATE_BLOCKED_QUEUE;
+ self->pt_sleepobj = cond;
+ self->pt_sleepq = &cond->ptc_waiters;
+ self->pt_sleeplock = &cond->ptc_lock;
+ pthread_spinunlock(self, &self->pt_statelock);
+
+ PTQ_INSERT_TAIL(&cond->ptc_waiters, self, pt_sleep);
+ pthread_mutex_unlock(mutex);
+
+ pthread__block(self, &cond->ptc_lock);
+ /* Spinlock is unlocked on return */
+ SDPRINTF(("(cond timed wait %p) Woke up on %p, mutex %p\n",
+ self, cond));
+ pthread__alarm_del(self, &alarm);
+ if (pthread__alarm_fired(&alarm))
+ retval = ETIMEDOUT;
+ SDPRINTF(("(cond timed wait %p) %s\n",
+ self, (retval == ETIMEDOUT) ? "(timed out)" : ""));
+ pthread_mutex_lock(mutex);
+ pthread__testcancel(self);
+
+
+ return retval;
+}
+
+static void
+pthread_cond_wait__callback(void *arg)
+{
+ struct pthread_cond__waitarg *a;
+ pthread_t self;
+
+ a = arg;
+ self = pthread__self();
+
+ /*
+ * Don't dequeue and schedule the thread if it's already been
+ * queued up by a signal or broadcast (but hasn't yet run as far
+ * as pthread__alarm_del(), or we wouldn't be here, and hence can't
+ * have become blocked on some *other* queue).
+ */
+ pthread_spinlock(self, &a->ptw_cond->ptc_lock);
+ if (a->ptw_thread->pt_state == PT_STATE_BLOCKED_QUEUE) {
+ PTQ_REMOVE(&a->ptw_cond->ptc_waiters, a->ptw_thread, pt_sleep);
+#ifdef ERRORCHECK
+ if (PTQ_EMPTY(&a->ptw_cond->ptc_waiters))
+ a->ptw_cond->ptc_mutex = NULL;
+#endif
+ pthread__sched(self, a->ptw_thread);
+ }
+ pthread_spinunlock(self, &a->ptw_cond->ptc_lock);
+}
+
+int
+pthread_cond_signal(pthread_cond_t *cond)
+{
+ pthread_t self, signaled;
+#ifdef ERRORCHECK
+ if ((cond == NULL) || (cond->ptc_magic != _PT_COND_MAGIC))
+ return EINVAL;
+#endif
+
+ self = pthread__self();
+ SDPRINTF(("(cond signal %p) Signaling %p\n",
+ self, cond));
+
+ pthread_spinlock(self, &cond->ptc_lock);
+ signaled = PTQ_FIRST(&cond->ptc_waiters);
+ if (signaled != NULL)
+ PTQ_REMOVE(&cond->ptc_waiters, signaled, pt_sleep);
+#ifdef ERRORCHECK
+ if (PTQ_EMPTY(&cond->ptc_waiters))
+ cond->ptc_mutex = NULL;
+#endif
+ if (signaled != NULL)
+ pthread__sched(self, signaled);
+ pthread_spinunlock(self, &cond->ptc_lock);
+
+ return 0;
+}
+
+
+int
+pthread_cond_broadcast(pthread_cond_t *cond)
+{
+ pthread_t self, signaled;
+ struct pthread_queue_t blockedq;
+#ifdef ERRORCHECK
+ if ((cond == NULL) || (cond->ptc_magic != _PT_COND_MAGIC))
+ return EINVAL;
+#endif
+
+ self = pthread__self();
+ SDPRINTF(("(cond signal %p) Broadcasting %p\n",
+ self, cond));
+
+ pthread_spinlock(self, &cond->ptc_lock);
+ blockedq = cond->ptc_waiters;
+ PTQ_INIT(&cond->ptc_waiters);
+#ifdef ERRORCHECK
+ cond->ptc_mutex = NULL;
+#endif
+ PTQ_FOREACH(signaled, &blockedq, pt_sleep)
+ pthread__sched(self, signaled);
+ pthread_spinunlock(self, &cond->ptc_lock);
+
+ return 0;
+
+}
+
+
+int
+pthread_condattr_init(pthread_condattr_t *attr)
+{
+
+#ifdef ERRORCHECK
+ if (attr == NULL)
+ return EINVAL;
+#endif
+
+ attr->ptca_magic = _PT_CONDATTR_MAGIC;
+
+ return 0;
+}
+
+
+int
+pthread_condattr_destroy(pthread_condattr_t *attr)
+{
+
+#ifdef ERRORCHECK
+ if ((attr == NULL) ||
+ (attr->ptca_magic != _PT_CONDATTR_MAGIC))
+ return EINVAL;
+#endif
+
+ attr->ptca_magic = _PT_CONDATTR_DEAD;
+
+ return 0;
+}