src/TortoiseMerge/libsvn_diff/mutex.c

   1 /*
   2  * svn_mutex.c: routines for mutual exclusion.
   3  *
   4  * ====================================================================
   5  *    Licensed to the Apache Software Foundation (ASF) under one
   6  *    or more contributor license agreements.  See the NOTICE file
   7  *    distributed with this work for additional information
   8  *    regarding copyright ownership.  The ASF licenses this file
   9  *    to you under the Apache License, Version 2.0 (the
  10  *    "License"); you may not use this file except in compliance
  11  *    with the License.  You may obtain a copy of the License at
  12  *
  13  *      http://www.apache.org/licenses/LICENSE-2.0
  14  *
  15  *    Unless required by applicable law or agreed to in writing,
  16  *    software distributed under the License is distributed on an
  17  *    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  18  *    KIND, either express or implied.  See the License for the
  19  *    specific language governing permissions and limitations
  20  *    under the License.
  21  * ====================================================================
  22  */
  23
  24 #include "svn_private_config.h"
  25 #include "private/svn_mutex.h"
  26
  27 svn_error_t *
  28 svn_mutex__init(svn_mutex__t **mutex_p,
  29                 svn_boolean_t mutex_required,
  30                 apr_pool_t *result_pool)
  31 {
  32   /* always initialize the mutex pointer, even though it is not
  33      strictly necessary if APR_HAS_THREADS has not been set */
  34   *mutex_p = NULL;
  35
  36 #if APR_HAS_THREADS
  37   if (mutex_required)
  38     {
  39       apr_thread_mutex_t *apr_mutex;
  40       apr_status_t status =
  41           apr_thread_mutex_create(&apr_mutex,
  42                                   APR_THREAD_MUTEX_DEFAULT,
  43                                   result_pool);
  44       if (status)
  45         return svn_error_wrap_apr(status, _("Can't create mutex"));
  46
  47       *mutex_p = apr_mutex;
  48     }
  49 #endif
  50
  51   return SVN_NO_ERROR;
  52 }
  53
  54 svn_error_t *
  55 svn_mutex__lock(svn_mutex__t *mutex)
  56 {
  57 #if APR_HAS_THREADS
  58   if (mutex)
  59     {
  60       apr_status_t status = apr_thread_mutex_lock(mutex);
  61       if (status)
  62         return svn_error_wrap_apr(status, _("Can't lock mutex"));
  63     }
  64 #endif
  65
  66   return SVN_NO_ERROR;
  67 }
  68
  69 svn_error_t *
  70 svn_mutex__unlock(svn_mutex__t *mutex,
  71                   svn_error_t *err)
  72 {
  73 #if APR_HAS_THREADS
  74   if (mutex)
  75     {
  76       apr_status_t status = apr_thread_mutex_unlock(mutex);
  77       if (status && !err)
  78         return svn_error_wrap_apr(status, _("Can't unlock mutex"));
  79     }
  80 #endif
  81
  82   return err;
  83 }