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--- Libc/Libc-498/pthreads/pthread_rwlock.c
+++ /dev/null
@@ -1,498 +0,0 @@
-/*
- * 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);
-}
-
-