fix event_sink race

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@15389 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/mod/event_handlers/mod_event_socket/mod_event_socket.c

@@ -79,6 +79,7 @@ struct listener {
 	int lost_events;
 	int lost_logs;
 	time_t last_flush;
+	time_t expire_time;
 	uint32_t timeout;
 	uint32_t id;
 	switch_sockaddr_t *sa;
@@ -190,11 +191,23 @@ static void flush_listener(listener_t *listener, switch_bool_t flush_log, switch
 	}
 }
 
-static void expire_listener(listener_t **listener)
+static switch_status_t expire_listener(listener_t **listener)
 {
+
+	if (!(*listener)->expire_time) {
+		(*listener)->expire_time = switch_epoch_time_now(NULL);
+		return SWITCH_STATUS_FALSE;
+	}
+
+	if (switch_thread_rwlock_trywrlock((*listener)->rwlock) != SWITCH_STATUS_SUCCESS) {
+		return SWITCH_STATUS_FALSE;
+	}
 	
+	if (globals.debug > 0) {
+		switch_log_printf(SWITCH_CHANNEL_SESSION_LOG((*listener)->session), SWITCH_LOG_DEBUG, "Stateful Listener %u has expired\n", (*listener)->id);
+	}
+
 	flush_listener(*listener, SWITCH_TRUE, SWITCH_TRUE);
-	switch_thread_rwlock_unlock((*listener)->rwlock);
 	switch_core_hash_destroy(&(*listener)->event_hash);
 	switch_core_destroy_memory_pool(&(*listener)->pool);
 	switch_mutex_lock((*listener)->filter_mutex);
@@ -202,13 +215,15 @@ static void expire_listener(listener_t **listener)
 		switch_event_destroy(&(*listener)->filters);
 	}
 	switch_mutex_unlock((*listener)->filter_mutex);
+	switch_thread_rwlock_unlock((*listener)->rwlock);
 	*listener = NULL;
+	return SWITCH_STATUS_SUCCESS;
 }
 
 static void event_handler(switch_event_t *event)
 {
 	switch_event_t *clone = NULL;
-	listener_t *l, *lp;
+	listener_t *l, *lp, *last = NULL;
 
 	switch_assert(event != NULL);
 
@@ -221,21 +236,26 @@ static void event_handler(switch_event_t *event)
 	switch_mutex_lock(globals.listener_mutex);
 	while(lp) {
 		int send = 0;
-		
+		time_t now = switch_epoch_time_now(NULL);
+
 		l = lp;
 		lp = lp->next;
 		
 		if (!switch_test_flag(l, LFLAG_EVENTS)) {
+			last = lp;
 			continue;
 		}
 		
-		if (switch_test_flag(l, LFLAG_STATEFUL) && l->timeout && switch_epoch_time_now(NULL) - l->last_flush > l->timeout) {
+		if (switch_test_flag(l, LFLAG_STATEFUL) && l->timeout && now - l->last_flush > l->timeout) {
-			if (globals.debug > 0) {
+			if (expire_listener(&l) == SWITCH_STATUS_SUCCESS) {
-				switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(l->session), SWITCH_LOG_WARNING, "Stateful Listener %u has expired\n", l->id);
+				if (last) {
+					last->next = lp;
+				} else {
+					listen_list.listeners = lp;
+				}
+				
+				continue;
 			}
-			remove_listener(l);
-			expire_listener(&l);
-			continue;
 		}
 		
 		
@@ -327,6 +347,7 @@ static void event_handler(switch_event_t *event)
 				switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(l->session), SWITCH_LOG_ERROR, "Memory Error!\n");
 			}
 		}
+		last = lp;
 	}
 	switch_mutex_unlock(globals.listener_mutex);
 }
@@ -540,7 +561,7 @@ static listener_t *find_listener(uint32_t id)
 
 	switch_mutex_lock(globals.listener_mutex);
 	for (l = listen_list.listeners; l; l = l->next) {
-		if (l->id && l->id == id) {
+		if (l->id && l->id == id && !l->expire_time) {
 			if (switch_thread_rwlock_tryrdlock(l->rwlock) == SWITCH_STATUS_SUCCESS) {
 				r = l;
 			}
@@ -823,11 +844,10 @@ SWITCH_STANDARD_API(event_sink_function)
 			if (globals.debug > 0) {
 				switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "Destroying event-sink listener [%u]\n", idl);
 			}
-			remove_listener(listener);
 			stream->write_function(stream, "<data>\n <reply type=\"success\">listener %u destroyed</reply>\n", listener->id);
 			xmlize_listener(listener, stream);
 			stream->write_function(stream, "</data>\n");
-			expire_listener(&listener);
+			listener->expire_time = switch_epoch_time_now(NULL);
 			goto end;
 		} else {
 			if (globals.debug > 0) {