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--- /dev/null
+++ Libc/Libc-498/pthreads/pthread_rwlock.c
@@ -0,0 +1,498 @@
+/*
+ * Copyright (c) 2000-2003, 2007 Apple Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * 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 (c) 1998 Alex Nash
+ * All rights reserved.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ *
+ * $FreeBSD: src/lib/libc_r/uthread/uthread_rwlock.c,v 1.6 2001/04/10 04:19:20 deischen Exp $
+ */
+
+/*
+ * POSIX Pthread Library
+ * -- Read Write Lock support
+ * 4/24/02: A. Ramesh
+ * Ported from FreeBSD
+ */
+
+#include "pthread_internals.h"
+extern int __unix_conforming;
+
+#include "plockstat.h"
+#define READ_LOCK_PLOCKSTAT 0
+#define WRITE_LOCK_PLOCKSTAT 1
+
+#define BLOCK_FAIL_PLOCKSTAT 0
+#define BLOCK_SUCCESS_PLOCKSTAT 1
+
+/* maximum number of times a read lock may be obtained */
+#define MAX_READ_LOCKS (INT_MAX - 1)
+
+
+#ifndef BUILDING_VARIANT /* [ */
+
+
+int
+pthread_rwlockattr_init(pthread_rwlockattr_t *attr)
+{
+ attr->sig = _PTHREAD_RWLOCK_ATTR_SIG;
+ attr->pshared = _PTHREAD_DEFAULT_PSHARED;
+ return (0);
+}
+
+int
+pthread_rwlockattr_destroy(pthread_rwlockattr_t *attr)
+{
+ attr->sig = _PTHREAD_NO_SIG; /* Uninitialized */
+ attr->pshared = 0;
+ return (0);
+}
+
+int
+pthread_rwlockattr_getpshared(const pthread_rwlockattr_t *attr,
+ int *pshared)
+{
+ if (attr->sig == _PTHREAD_RWLOCK_ATTR_SIG)
+ {
+ *pshared = (int)attr->pshared;
+ return (0);
+ } else
+ {
+ return (EINVAL); /* Not an initialized 'attribute' structure */
+ }
+}
+
+/* Temp: untill pshared is fixed right */
+#ifdef PR_5243343
+/* 5243343 - temporary hack to detect if we are running the conformance test */
+extern int PR_5243343_flag;
+#endif /* PR_5243343 */
+
+int
+pthread_rwlockattr_setpshared(pthread_rwlockattr_t * attr, int pshared)
+{
+ if (attr->sig == _PTHREAD_RWLOCK_ATTR_SIG)
+ {
+#if __DARWIN_UNIX03
+#ifdef PR_5243343
+ if (( pshared == PTHREAD_PROCESS_PRIVATE) || (pshared == PTHREAD_PROCESS_SHARED && PR_5243343_flag))
+#else /* !PR_5243343 */
+ if (( pshared == PTHREAD_PROCESS_PRIVATE) || (pshared == PTHREAD_PROCESS_SHARED))
+#endif /* PR_5243343 */
+#else /* __DARWIN_UNIX03 */
+ if ( pshared == PTHREAD_PROCESS_PRIVATE)
+#endif /* __DARWIN_UNIX03 */
+ {
+ attr->pshared = pshared ;
+ return (0);
+ } else
+ {
+ return (EINVAL); /* Invalid parameter */
+ }
+ } else
+ {
+ return (EINVAL); /* Not an initialized 'attribute' structure */
+ }
+
+}
+
+#endif /* !BUILDING_VARIANT ] */
+
+int
+pthread_rwlock_destroy(pthread_rwlock_t *rwlock)
+{
+ int ret;
+
+ if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+ return(EINVAL);
+ } else {
+#if __DARWIN_UNIX03
+ /* grab the monitor lock */
+ if ((ret = pthread_mutex_lock(&rwlock->lock)) != 0)
+ return(ret);
+
+ if (rwlock->state != 0) {
+ pthread_mutex_unlock(&rwlock->lock);
+ return(EBUSY);
+ }
+ pthread_mutex_unlock(&rwlock->lock);
+#endif /* __DARWIN_UNIX03 */
+
+ pthread_mutex_destroy(&rwlock->lock);
+ pthread_cond_destroy(&rwlock->read_signal);
+ pthread_cond_destroy(&rwlock->write_signal);
+ rwlock->sig = _PTHREAD_NO_SIG;
+ return(0);
+ }
+}
+
+int
+pthread_rwlock_init(pthread_rwlock_t *rwlock, const pthread_rwlockattr_t *attr)
+{
+ int ret;
+#if __DARWIN_UNIX03
+ if (attr && (attr->sig != _PTHREAD_RWLOCK_ATTR_SIG)) {
+ return(EINVAL);
+ }
+ /* if already inited check whether it is in use, then return EBUSY */
+ if ((rwlock->sig == _PTHREAD_RWLOCK_SIG) && (rwlock->state !=0 )) {
+ return(EBUSY);
+ }
+#endif /* __DARWIN_UNIX03 */
+
+ /* initialize the lock */
+ if ((ret = pthread_mutex_init(&rwlock->lock, NULL)) != 0)
+ return(ret);
+ else {
+ /* initialize the read condition signal */
+ ret = pthread_cond_init(&rwlock->read_signal, NULL);
+
+ if (ret != 0) {
+ pthread_mutex_destroy(&rwlock->lock);
+ return(ret);
+ } else {
+ /* initialize the write condition signal */
+ ret = pthread_cond_init(&rwlock->write_signal, NULL);
+
+ if (ret != 0) {
+ pthread_cond_destroy(&rwlock->read_signal);
+ pthread_mutex_destroy(&rwlock->lock);
+ return(ret);
+ } else {
+ /* success */
+ rwlock->state = 0;
+ rwlock->owner = (pthread_t)0;
+ rwlock->blocked_writers = 0;
+ if (attr)
+ rwlock->pshared = attr->pshared;
+ else
+ rwlock->pshared = _PTHREAD_DEFAULT_PSHARED;
+
+ rwlock->sig = _PTHREAD_RWLOCK_SIG;
+ return(0);
+ }
+ }
+ }
+}
+
+int
+pthread_rwlock_rdlock(pthread_rwlock_t *rwlock)
+{
+ int ret;
+#if __DARWIN_UNIX03
+ pthread_t self = pthread_self();
+#endif
+
+ if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+ if ((ret = pthread_rwlock_init(rwlock, NULL)) != 0) {
+ PLOCKSTAT_RW_ERROR(rwlock, READ_LOCK_PLOCKSTAT, ret);
+ return(ret);
+ }
+ }
+
+ if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+ PLOCKSTAT_RW_ERROR(rwlock, READ_LOCK_PLOCKSTAT, EINVAL);
+ return(EINVAL);
+ }
+ /* grab the monitor lock */
+ if ((ret = pthread_mutex_lock(&rwlock->lock)) != 0) {
+ PLOCKSTAT_RW_ERROR(rwlock, READ_LOCK_PLOCKSTAT, ret);
+ return(ret);
+ }
+
+#if __DARWIN_UNIX03
+ if ((rwlock->state < 0) && (rwlock->owner == self)) {
+ pthread_mutex_unlock(&rwlock->lock);
+ PLOCKSTAT_RW_ERROR(rwlock, READ_LOCK_PLOCKSTAT, EDEADLK);
+ return(EDEADLK);
+ }
+#endif /* __DARWIN_UNIX03 */
+
+#if __DARWIN_UNIX03
+ while (rwlock->blocked_writers || ((rwlock->state < 0) && (rwlock->owner != self)))
+#else /* __DARWIN_UNIX03 */
+ while (rwlock->blocked_writers || rwlock->state < 0)
+
+#endif /* __DARWIN_UNIX03 */
+ {
+ /* give writers priority over readers */
+ PLOCKSTAT_RW_BLOCK(rwlock, READ_LOCK_PLOCKSTAT);
+ ret = pthread_cond_wait(&rwlock->read_signal, &rwlock->lock);
+
+ if (ret != 0) {
+ /* can't do a whole lot if this fails */
+ pthread_mutex_unlock(&rwlock->lock);
+ PLOCKSTAT_RW_BLOCKED(rwlock, READ_LOCK_PLOCKSTAT, BLOCK_FAIL_PLOCKSTAT);
+ PLOCKSTAT_RW_ERROR(rwlock, READ_LOCK_PLOCKSTAT, ret);
+ return(ret);
+ }
+
+ PLOCKSTAT_RW_BLOCKED(rwlock, READ_LOCK_PLOCKSTAT, BLOCK_SUCCESS_PLOCKSTAT);
+ }
+
+ /* check lock count */
+ if (rwlock->state == MAX_READ_LOCKS) {
+ ret = EAGAIN;
+ PLOCKSTAT_RW_ERROR(rwlock, READ_LOCK_PLOCKSTAT, ret);
+ }
+ else {
+ ++rwlock->state; /* indicate we are locked for reading */
+ PLOCKSTAT_RW_ACQUIRE(rwlock, READ_LOCK_PLOCKSTAT);
+ }
+
+ /*
+ * Something is really wrong if this call fails. Returning
+ * error won't do because we've already obtained the read
+ * lock. Decrementing 'state' is no good because we probably
+ * don't have the monitor lock.
+ */
+ pthread_mutex_unlock(&rwlock->lock);
+
+ return(ret);
+}
+
+int
+pthread_rwlock_tryrdlock(pthread_rwlock_t *rwlock)
+{
+ int ret;
+#if __DARWIN_UNIX03
+ pthread_t self = pthread_self();
+#endif
+
+ /* check for static initialization */
+ if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+ if ((ret = pthread_rwlock_init(rwlock, NULL)) != 0) {
+ PLOCKSTAT_RW_ERROR(rwlock, READ_LOCK_PLOCKSTAT, ret);
+ return(ret);
+ }
+ }
+
+ if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+ PLOCKSTAT_RW_ERROR(rwlock, READ_LOCK_PLOCKSTAT, EINVAL);
+ return(EINVAL);
+ }
+ /* grab the monitor lock */
+ if ((ret = pthread_mutex_lock(&rwlock->lock)) != 0) {
+ PLOCKSTAT_RW_ERROR(rwlock, READ_LOCK_PLOCKSTAT, ret);
+ return(ret);
+ }
+
+ /* give writers priority over readers */
+ if (rwlock->blocked_writers || rwlock->state < 0) {
+ ret = EBUSY;
+ PLOCKSTAT_RW_ERROR(rwlock, READ_LOCK_PLOCKSTAT, ret);
+ }
+ else if (rwlock->state == MAX_READ_LOCKS) {
+ ret = EAGAIN; /* too many read locks acquired */
+ PLOCKSTAT_RW_ERROR(rwlock, READ_LOCK_PLOCKSTAT, ret);
+ }
+ else {
+ ++rwlock->state; /* indicate we are locked for reading */
+ PLOCKSTAT_RW_ACQUIRE(rwlock, READ_LOCK_PLOCKSTAT);
+ }
+
+ /* see the comment on this in pthread_rwlock_rdlock */
+ pthread_mutex_unlock(&rwlock->lock);
+
+ return(ret);
+}
+
+int
+pthread_rwlock_trywrlock(pthread_rwlock_t *rwlock)
+{
+ int ret;
+#if __DARWIN_UNIX03
+ pthread_t self = pthread_self();
+#endif /* __DARWIN_UNIX03 */
+
+ /* check for static initialization */
+ if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+ if ((ret = pthread_rwlock_init(rwlock, NULL)) != 0) {
+ PLOCKSTAT_RW_ERROR(rwlock, WRITE_LOCK_PLOCKSTAT, ret);
+ return(ret);
+ }
+ }
+
+ if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+ PLOCKSTAT_RW_ERROR(rwlock, WRITE_LOCK_PLOCKSTAT, EINVAL);
+ return(EINVAL);
+ }
+ /* grab the monitor lock */
+ if ((ret = pthread_mutex_lock(&rwlock->lock)) != 0) {
+ PLOCKSTAT_RW_ERROR(rwlock, WRITE_LOCK_PLOCKSTAT, ret);
+ return(ret);
+ }
+
+
+ if (rwlock->state != 0) {
+ ret = EBUSY;
+ PLOCKSTAT_RW_ERROR(rwlock, WRITE_LOCK_PLOCKSTAT, ret);
+ }
+ else {
+ /* indicate we are locked for writing */
+ rwlock->state = -1;
+#if __DARWIN_UNIX03
+ rwlock->owner = self;
+#endif /* __DARWIN_UNIX03 */
+ PLOCKSTAT_RW_ACQUIRE(rwlock, WRITE_LOCK_PLOCKSTAT);
+ }
+
+ /* see the comment on this in pthread_rwlock_rdlock */
+ pthread_mutex_unlock(&rwlock->lock);
+
+ return(ret);
+}
+
+int
+pthread_rwlock_unlock(pthread_rwlock_t *rwlock)
+{
+ int ret;
+ int writer = (rwlock < 0) ? 1:0;
+#if __DARWIN_UNIX03
+ pthread_t self = pthread_self();
+#endif /* __DARWIN_UNIX03 */
+
+ if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+ PLOCKSTAT_RW_ERROR(rwlock, writer, EINVAL);
+ return(EINVAL);
+ }
+ /* grab the monitor lock */
+ if ((ret = pthread_mutex_lock(&rwlock->lock)) != 0) {
+ PLOCKSTAT_RW_ERROR(rwlock, writer, ret);
+ return(ret);
+ }
+
+ if (rwlock->state > 0) {
+ if (--rwlock->state == 0 && rwlock->blocked_writers)
+ ret = pthread_cond_signal(&rwlock->write_signal);
+ } else if (rwlock->state < 0) {
+ rwlock->state = 0;
+#if __DARWIN_UNIX03
+ rwlock->owner = (pthread_t)0;
+#endif /* __DARWIN_UNIX03 */
+
+ if (rwlock->blocked_writers)
+ ret = pthread_cond_signal(&rwlock->write_signal);
+ else
+ ret = pthread_cond_broadcast(&rwlock->read_signal);
+ } else
+ ret = EINVAL;
+
+ if (ret == 0) {
+ PLOCKSTAT_RW_RELEASE(rwlock, writer);
+ } else {
+ PLOCKSTAT_RW_ERROR(rwlock, writer, ret);
+ }
+
+ /* see the comment on this in pthread_rwlock_rdlock */
+ pthread_mutex_unlock(&rwlock->lock);
+
+ return(ret);
+}
+
+int
+pthread_rwlock_wrlock(pthread_rwlock_t *rwlock)
+{
+ int ret;
+#if __DARWIN_UNIX03
+ pthread_t self = pthread_self();
+#endif /* __DARWIN_UNIX03 */
+
+ /* check for static initialization */
+ if (rwlock->sig == _PTHREAD_RWLOCK_SIG_init) {
+ if ((ret = pthread_rwlock_init(rwlock, NULL)) != 0) {
+ PLOCKSTAT_RW_ERROR(rwlock, WRITE_LOCK_PLOCKSTAT, ret);
+ return(ret);
+ }
+ }
+
+ if (rwlock->sig != _PTHREAD_RWLOCK_SIG) {
+ PLOCKSTAT_RW_ERROR(rwlock, WRITE_LOCK_PLOCKSTAT, EINVAL);
+ return(EINVAL);
+ }
+ /* grab the monitor lock */
+ if ((ret = pthread_mutex_lock(&rwlock->lock)) != 0) {
+ PLOCKSTAT_RW_ERROR(rwlock, WRITE_LOCK_PLOCKSTAT, ret);
+ return(ret);
+ }
+
+#if __DARWIN_UNIX03
+ if ((rwlock->state < 0) && (rwlock->owner == self)) {
+ pthread_mutex_unlock(&rwlock->lock);
+ PLOCKSTAT_RW_ERROR(rwlock, WRITE_LOCK_PLOCKSTAT, EDEADLK);
+ return(EDEADLK);
+ }
+#endif /* __DARWIN_UNIX03 */
+ while (rwlock->state != 0) {
+ ++rwlock->blocked_writers;
+
+ PLOCKSTAT_RW_BLOCK(rwlock, WRITE_LOCK_PLOCKSTAT);
+ ret = pthread_cond_wait(&rwlock->write_signal, &rwlock->lock);
+
+ if (ret != 0) {
+ --rwlock->blocked_writers;
+ pthread_mutex_unlock(&rwlock->lock);
+ PLOCKSTAT_RW_BLOCKED(rwlock, WRITE_LOCK_PLOCKSTAT, BLOCK_FAIL_PLOCKSTAT);
+ PLOCKSTAT_RW_ERROR(rwlock, WRITE_LOCK_PLOCKSTAT, ret);
+ return(ret);
+ }
+
+ PLOCKSTAT_RW_BLOCKED(rwlock, WRITE_LOCK_PLOCKSTAT, BLOCK_SUCCESS_PLOCKSTAT);
+
+ --rwlock->blocked_writers;
+ }
+
+ /* indicate we are locked for writing */
+ rwlock->state = -1;
+#if __DARWIN_UNIX03
+ rwlock->owner = self;
+#endif /* __DARWIN_UNIX03 */
+ PLOCKSTAT_RW_ACQUIRE(rwlock, WRITE_LOCK_PLOCKSTAT);
+
+ /* see the comment on this in pthread_rwlock_rdlock */
+ pthread_mutex_unlock(&rwlock->lock);
+
+ return(ret);
+}
+
+