thread_rwlock.c   [plain text]

/* Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "apr.h"
#include "apr_private.h"
#include "apr_general.h"
#include "apr_strings.h"
#include "apr_arch_thread_rwlock.h"
#include "apr_portable.h"

static apr_status_t thread_rwlock_cleanup(void *data)
{
    apr_thread_rwlock_t *rwlock = (apr_thread_rwlock_t *)data;

    NXRwLockFree (rwlock->rwlock);
    return APR_SUCCESS;
} 

APR_DECLARE(apr_status_t) apr_thread_rwlock_create(apr_thread_rwlock_t **rwlock,
                                                   apr_pool_t *pool)
{
    apr_thread_rwlock_t *new_rwlock = NULL;
   
    NXHierarchy_t hierarchy = 1;   /* for libc NKS NXRwLockAlloc */
    NXLockInfo_t *info;            /* for libc NKS NXRwLockAlloc */

    new_rwlock = (apr_thread_rwlock_t *)apr_pcalloc(pool, sizeof(apr_thread_rwlock_t));

    if(new_rwlock ==NULL) {
        return APR_ENOMEM;
    }     
    new_rwlock->pool = pool;
    
    info = (NXLockInfo_t *)apr_pcalloc(pool, sizeof(NXLockInfo_t));
    new_rwlock->rwlock = NXRwLockAlloc(hierarchy, info);
    if(new_rwlock->rwlock == NULL)
        return APR_ENOMEM;

    apr_pool_cleanup_register(new_rwlock->pool, new_rwlock, thread_rwlock_cleanup,
                              apr_pool_cleanup_null);
    *rwlock = new_rwlock;

    return APR_SUCCESS;
}

APR_DECLARE(apr_status_t) apr_thread_rwlock_rdlock(apr_thread_rwlock_t *rwlock)
{
    NXRdLock(rwlock->rwlock);
    return APR_SUCCESS;
}

APR_DECLARE(apr_status_t) apr_thread_rwlock_tryrdlock(apr_thread_rwlock_t *rwlock)
{
    if (!NXTryRdLock(rwlock->rwlock))
        return APR_EBUSY;
    return APR_SUCCESS;
}

APR_DECLARE(apr_status_t) apr_thread_rwlock_wrlock(apr_thread_rwlock_t *rwlock)
{
    NXWrLock(rwlock->rwlock);
    return APR_SUCCESS;
}

APR_DECLARE(apr_status_t) apr_thread_rwlock_trywrlock(apr_thread_rwlock_t *rwlock)
{
    if (!NXTryWrLock(rwlock->rwlock))
        return APR_EBUSY;
    return APR_SUCCESS;
}

APR_DECLARE(apr_status_t) apr_thread_rwlock_unlock(apr_thread_rwlock_t *rwlock)
{
    NXRwUnlock(rwlock->rwlock);
    return APR_SUCCESS;
}

APR_DECLARE(apr_status_t) apr_thread_rwlock_destroy(apr_thread_rwlock_t *rwlock)
{
    apr_status_t stat;
    if ((stat = thread_rwlock_cleanup(rwlock)) == APR_SUCCESS) {
        apr_pool_cleanup_kill(rwlock->pool, rwlock, thread_rwlock_cleanup);
        return APR_SUCCESS;
    }
    return stat;
}

APR_POOL_IMPLEMENT_ACCESSOR(thread_rwlock)