Author: stefan2
Date: Thu Apr 12 20:02:36 2012
New Revision: 1325478
URL: http://svn.apache.org/viewvc?rev=1325478&view=rev
Log:
Introduce a new API function to create and initialize a new
APR pool allocator. Make its thread-safety properties
explicit in the docstring.
Will be used by the next commit to replace boilerplate code.
* subversion/include/svn_pools.h
(svn_pool_create_allocator): declare new API function
* subversion/libsvn_subr/pool.c
(svn_pool_create_allocator): declare new API function
Modified:
subversion/trunk/subversion/include/svn_pools.h
subversion/trunk/subversion/libsvn_subr/pool.c
Modified: subversion/trunk/subversion/include/svn_pools.h
URL:
http://svn.apache.org/viewvc/subversion/trunk/subversion/include/svn_pools.h?rev=1325478&r1=1325477&r2=1325478&view=diff
==============================================================================
--- subversion/trunk/subversion/include/svn_pools.h (original)
+++ subversion/trunk/subversion/include/svn_pools.h Thu Apr 12 20:02:36 2012
@@ -30,7 +30,7 @@
#ifndef SVN_POOLS_H
#define SVN_POOLS_H
-#include <apr_pools.h>
+#include "svn_types.h"
#ifdef __cplusplus
extern "C" {
@@ -86,6 +86,23 @@ svn_pool_create_ex_debug(pool, allocator
*/
#define svn_pool_destroy apr_pool_destroy
+/** Return a new allocator. This function limits the unused memory in the
+ * new allocator to @ref SVN_ALLOCATOR_RECOMMENDED_MAX_FREE and ensures
+ * proper synchronization if the allocator is used by multiple threads.
+ *
+ * If your application uses multiple threads, creating a separate allocator
+ * for each of these threads may not be feasible. Set the @a thread_safe
+ * parameter to @c TRUE in that case. Pools will still not thread-safe, i.e.
+ * access to them may require explicit serialization. Set the parameter to
+ * @c FALSE, otherwise, to maximize performance.
+ *
+ * To access the owner pool, which can also serve as the root pool for your
+ * sub-pools, call @c apr_allocator_get_owner().
+ *
+ * @since: New in 1.8
+ */
+apr_allocator_t *
+svn_pool_create_allocator(svn_boolean_t thread_safe);
#ifdef __cplusplus
}
Modified: subversion/trunk/subversion/libsvn_subr/pool.c
URL:
http://svn.apache.org/viewvc/subversion/trunk/subversion/libsvn_subr/pool.c?rev=1325478&r1=1325477&r2=1325478&view=diff
==============================================================================
--- subversion/trunk/subversion/libsvn_subr/pool.c (original)
+++ subversion/trunk/subversion/libsvn_subr/pool.c Thu Apr 12 20:02:36 2012
@@ -28,6 +28,7 @@
#include <apr_general.h>
#include <apr_pools.h>
+#include <apr_thread_mutex.h>
#include "svn_pools.h"
@@ -97,3 +98,44 @@ svn_pool_create_ex(apr_pool_t *pool, apr
}
#endif /* APR_POOL_DEBUG */
+
+apr_allocator_t *
+svn_pool_create_allocator(svn_boolean_t thread_safe)
+{
+ apr_allocator_t *allocator;
+ apr_pool_t *pool;
+
+ /* create the allocator and limit it's internal free list to keep
+ * memory usage in check */
+
+ if (apr_allocator_create(&allocator))
+ abort_on_pool_failure(EXIT_FAILURE);
+
+ apr_allocator_max_free_set(allocator, SVN_ALLOCATOR_RECOMMENDED_MAX_FREE);
+
+ /* create the root pool */
+
+ pool = svn_pool_create_ex(NULL, allocator);
+ apr_allocator_owner_set(allocator, pool);
+
+#if APR_POOL_DEBUG
+ apr_pool_tag (pool, "svn root pool");
+#endif
+
+ /* By default, allocators are *not* thread-safe. We must provide a mutex
+ * if we want thread-safety for that mutex. */
+
+#if APR_HAS_THREADS
+ if (thread_safe)
+ {
+ apr_thread_mutex_t *mutex;
+ apr_thread_mutex_create (&mutex, APR_THREAD_MUTEX_DEFAULT, pool);
+ apr_allocator_mutex_set (allocator, mutex);
+ }
+#endif
+
+ /* better safe than sorry */
+ SVN_ERR_ASSERT_NO_RETURN(allocator != NULL);
+
+ return allocator;
+}
