contrib/apr/locks/unix/thread_rwlock.c

   1 /* Licensed to the Apache Software Foundation (ASF) under one or more
   2  * contributor license agreements.  See the NOTICE file distributed with
   3  * this work for additional information regarding copyright ownership.
   4  * The ASF licenses this file to You under the Apache License, Version 2.0
   5  * (the "License"); you may not use this file except in compliance with
   6  * the License.  You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include "apr_arch_thread_rwlock.h"
  18 #include "apr_private.h"
  19
  20 #if APR_HAS_THREADS
  21
  22 #ifdef HAVE_PTHREAD_RWLOCKS
  23
  24 /* The rwlock must be initialized but not locked by any thread when
  25  * cleanup is called. */
  26 static apr_status_t thread_rwlock_cleanup(void *data)
  27 {
  28     apr_thread_rwlock_t *rwlock = (apr_thread_rwlock_t *)data;
  29     apr_status_t stat;
  30
  31     stat = pthread_rwlock_destroy(&rwlock->rwlock);
  32 #ifdef HAVE_ZOS_PTHREADS
  33     if (stat) {
  34         stat = errno;
  35     }
  36 #endif
  37     return stat;
  38 }
  39
  40 APR_DECLARE(apr_status_t) apr_thread_rwlock_create(apr_thread_rwlock_t **rwlock,
  41                                                    apr_pool_t *pool)
  42 {
  43     apr_thread_rwlock_t *new_rwlock;
  44     apr_status_t stat;
  45
  46     new_rwlock = apr_palloc(pool, sizeof(apr_thread_rwlock_t));
  47     new_rwlock->pool = pool;
  48
  49     if ((stat = pthread_rwlock_init(&new_rwlock->rwlock, NULL))) {
  50 #ifdef HAVE_ZOS_PTHREADS
  51         stat = errno;
  52 #endif
  53         return stat;
  54     }
  55
  56     apr_pool_cleanup_register(new_rwlock->pool,
  57                               (void *)new_rwlock, thread_rwlock_cleanup,
  58                               apr_pool_cleanup_null);
  59
  60     *rwlock = new_rwlock;
  61     return APR_SUCCESS;
  62 }
  63
  64 APR_DECLARE(apr_status_t) apr_thread_rwlock_rdlock(apr_thread_rwlock_t *rwlock)
  65 {
  66     apr_status_t stat;
  67
  68     stat = pthread_rwlock_rdlock(&rwlock->rwlock);
  69 #ifdef HAVE_ZOS_PTHREADS
  70     if (stat) {
  71         stat = errno;
  72     }
  73 #endif
  74     return stat;
  75 }
  76
  77 APR_DECLARE(apr_status_t) apr_thread_rwlock_tryrdlock(apr_thread_rwlock_t *rwlock)
  78 {
  79     apr_status_t stat;
  80
  81     stat = pthread_rwlock_tryrdlock(&rwlock->rwlock);
  82 #ifdef HAVE_ZOS_PTHREADS
  83     if (stat) {
  84         stat = errno;
  85     }
  86 #endif
  87     /* Normalize the return code. */
  88     if (stat == EBUSY)
  89         stat = APR_EBUSY;
  90     return stat;
  91 }
  92
  93 APR_DECLARE(apr_status_t) apr_thread_rwlock_wrlock(apr_thread_rwlock_t *rwlock)
  94 {
  95     apr_status_t stat;
  96
  97     stat = pthread_rwlock_wrlock(&rwlock->rwlock);
  98 #ifdef HAVE_ZOS_PTHREADS
  99     if (stat) {
 100         stat = errno;
 101     }
 102 #endif
 103     return stat;
 104 }
 105
 106 APR_DECLARE(apr_status_t) apr_thread_rwlock_trywrlock(apr_thread_rwlock_t *rwlock)
 107 {
 108     apr_status_t stat;
 109
 110     stat = pthread_rwlock_trywrlock(&rwlock->rwlock);
 111 #ifdef HAVE_ZOS_PTHREADS
 112     if (stat) {
 113         stat = errno;
 114     }
 115 #endif
 116     /* Normalize the return code. */
 117     if (stat == EBUSY)
 118         stat = APR_EBUSY;
 119     return stat;
 120 }
 121
 122 APR_DECLARE(apr_status_t) apr_thread_rwlock_unlock(apr_thread_rwlock_t *rwlock)
 123 {
 124     apr_status_t stat;
 125
 126     stat = pthread_rwlock_unlock(&rwlock->rwlock);
 127 #ifdef HAVE_ZOS_PTHREADS
 128     if (stat) {
 129         stat = errno;
 130     }
 131 #endif
 132     return stat;
 133 }
 134
 135 APR_DECLARE(apr_status_t) apr_thread_rwlock_destroy(apr_thread_rwlock_t *rwlock)
 136 {
 137     return apr_pool_cleanup_run(rwlock->pool, rwlock, thread_rwlock_cleanup);
 138 }
 139
 140 #else  /* HAVE_PTHREAD_RWLOCKS */
 141
 142 APR_DECLARE(apr_status_t) apr_thread_rwlock_create(apr_thread_rwlock_t **rwlock,
 143                                                    apr_pool_t *pool)
 144 {
 145     return APR_ENOTIMPL;
 146 }
 147
 148 APR_DECLARE(apr_status_t) apr_thread_rwlock_rdlock(apr_thread_rwlock_t *rwlock)
 149 {
 150     return APR_ENOTIMPL;
 151 }
 152
 153 APR_DECLARE(apr_status_t) apr_thread_rwlock_tryrdlock(apr_thread_rwlock_t *rwlock)
 154 {
 155     return APR_ENOTIMPL;
 156 }
 157
 158 APR_DECLARE(apr_status_t) apr_thread_rwlock_wrlock(apr_thread_rwlock_t *rwlock)
 159 {
 160     return APR_ENOTIMPL;
 161 }
 162
 163 APR_DECLARE(apr_status_t) apr_thread_rwlock_trywrlock(apr_thread_rwlock_t *rwlock)
 164 {
 165     return APR_ENOTIMPL;
 166 }
 167
 168 APR_DECLARE(apr_status_t) apr_thread_rwlock_unlock(apr_thread_rwlock_t *rwlock)
 169 {
 170     return APR_ENOTIMPL;
 171 }
 172
 173 APR_DECLARE(apr_status_t) apr_thread_rwlock_destroy(apr_thread_rwlock_t *rwlock)
 174 {
 175     return APR_ENOTIMPL;
 176 }
 177
 178 #endif /* HAVE_PTHREAD_RWLOCKS */
 179 APR_POOL_IMPLEMENT_ACCESSOR(thread_rwlock)
 180
 181 #endif /* APR_HAS_THREADS */