subversion-1.9.7HEADsubversion-1.9.7master

1 files changed, 110 insertions, 0 deletions

diff --git a/subversion/libsvn_subr/root_pools.c b/subversion/libsvn_subr/root_pools.c
new file mode 100644
index 0000000..12096d9
--- /dev/null
+++ b/subversion/libsvn_subr/root_pools.c
@@ -0,0 +1,110 @@
+/*
+ * root_pools.c :  Implement svn_root_pools__* API
+ *
+ * ====================================================================
+ *    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 "svn_pools.h"
+
+#include "private/svn_subr_private.h"
+#include "private/svn_mutex.h"
+
+struct svn_root_pools__t
+{
+  /* unused pools.
+   * Use MUTEX to serialize access to this collection.
+   */
+  apr_array_header_t *unused_pools;
+
+  /* Mutex to serialize access to UNUSED_POOLS */
+  svn_mutex__t *mutex;
+
+};
+
+svn_error_t *
+svn_root_pools__create(svn_root_pools__t **pools)
+{
+  /* the collection of root pools must be managed independently from
+     any other pool */
+  apr_pool_t *pool
+    = apr_allocator_owner_get(svn_pool_create_allocator(FALSE));
+
+  /* construct result object */
+  svn_root_pools__t *result = apr_pcalloc(pool, sizeof(*result));
+  SVN_ERR(svn_mutex__init(&result->mutex, TRUE, pool));
+  result->unused_pools = apr_array_make(pool, 16, sizeof(apr_pool_t *));
+
+  /* done */
+  *pools = result;
+
+  return SVN_NO_ERROR;
+}
+
+/* Return a currently unused connection pool in *POOL. If no such pool
+ * exists, create a new root pool and return that in *POOL.
+ */
+static svn_error_t *
+acquire_pool_internal(apr_pool_t **pool,
+                      svn_root_pools__t *pools)
+{
+  SVN_ERR(svn_mutex__lock(pools->mutex));
+  *pool = pools->unused_pools->nelts
+        ? *(apr_pool_t **)apr_array_pop(pools->unused_pools)
+        : apr_allocator_owner_get(svn_pool_create_allocator(FALSE));
+  SVN_ERR(svn_mutex__unlock(pools->mutex, SVN_NO_ERROR));
+
+  return SVN_NO_ERROR;
+}
+
+apr_pool_t *
+svn_root_pools__acquire_pool(svn_root_pools__t *pools)
+{
+  apr_pool_t *pool;
+  svn_error_t *err = acquire_pool_internal(&pool, pools);
+  if (err)
+    {
+      /* Mutex failure?!  Well, try to continue with unrecycled data. */
+      svn_error_clear(err);
+      pool = apr_allocator_owner_get(svn_pool_create_allocator(FALSE));
+    }
+
+  return pool;
+}
+
+void
+svn_root_pools__release_pool(apr_pool_t *pool,
+                             svn_root_pools__t *pools)
+{
+  svn_error_t *err;
+
+  svn_pool_clear(pool);
+
+  err = svn_mutex__lock(pools->mutex);
+  if (err)
+    {
+      svn_error_clear(err);
+      svn_pool_destroy(pool);
+    }
+  else
+    {
+      APR_ARRAY_PUSH(pools->unused_pools, apr_pool_t *) = pool;
+      svn_error_clear(svn_mutex__unlock(pools->mutex, SVN_NO_ERROR));
+    }
+}