New astobj2 flag for issuing a callback without locking the container.

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@299135 65c4cc65-6c06-0410-ace0-fbb531ad65f3

include/asterisk/astobj2.h

@@ -674,6 +674,12 @@ enum search_flags {
 	 * the hash value on the argument.
 	 */
 	OBJ_CONTINUE     = (1 << 4),
+	/*! 
+	 * \brief By using this flag, the ao2_container being searched will _NOT_
+	 * be locked.  Only use this flag if the ao2_container is being protected
+	 * by another mechanism other that the internal ao2_lock.
+	 */
+	OBJ_NOLOCK     = (1 << 5),
 };
 
 /*!

main/astobj2.c

@@ -654,7 +654,10 @@ static void *internal_ao2_callback(struct ao2_container *c,
 		last = i + 1;
 	}
 
-	ao2_lock(c);	/* avoid modifications to the content */
+
+	if (!(flags & OBJ_NOLOCK)) {
+		ao2_lock(c);	/* avoid modifications to the content */
+	}
 
 	for (; i < last ; i++) {
 		/* scan the list with prev-cur pointers */
@@ -738,7 +741,10 @@ static void *internal_ao2_callback(struct ao2_container *c,
 			last = start;
 		}
 	}
-	ao2_unlock(c);
+
+	if (!(flags & OBJ_NOLOCK)) {
+		ao2_unlock(c);
+	}
 
 	/* if multi_container was created, we are returning multiple objects */
 	if (multi_container != NULL) {