Fix to bug #612, http://bugs.mariadb.com/show_bug.cgi?id=612

Also added error logging in cases where memory allocation failed etc.

server/core/dbusers.c

@@ -646,7 +646,13 @@ getUsers(SERVICE *service, USERS *users)
 
 	users_data = (char *)calloc(nusers, (users_data_row_len * sizeof(char)) + 1);
 
-	if(users_data == NULL) {
+	if (users_data == NULL) {
+		LOGIF(LE, (skygw_log_write_flush(
+			LOGFILE_ERROR,
+			"Error : Memory allocation for user data failed due to "
+			"%d, %s.",
+			errno,
+			strerror(errno))));
 		mysql_free_result(result);
 		mysql_close(con);
 

server/core/service.c

@@ -196,8 +196,13 @@ GWPROTOCOL	*funcs;
 
         if (port->listener == NULL)
 	{
-		return 0;
+		LOGIF(LE, (skygw_log_write_flush(
+			LOGFILE_ERROR,
+			"Error : Failed to create listener for service %s.",
+			service->name)));
+		goto retblock;
 	}
+	
 	if (strcmp(port->protocol, "MySQLClient") == 0) {
 		int loaded;
 
@@ -206,12 +211,25 @@ GWPROTOCOL	*funcs;
 		 * including hosts and db names
 		 */
 		service->users = mysql_users_alloc();
-		loaded = load_mysql_users(service);
-
+		
+		if ((loaded = load_mysql_users(service)) < 0)
+		{
+			LOGIF(LE, (skygw_log_write_flush(
+				LOGFILE_ERROR,
+				"Error : Unable to load users from %s:%d for "
+				"service %s.",
+				port->address,
+				port->port,
+				service->name)));
+			hashtable_free(service->users->data);
+			free(service->users);
+			dcb_free(port->listener);
+			port->listener = NULL;
+			goto retblock;
+		}
 		/* At service start last update is set to USERS_REFRESH_TIME seconds earlier.
  		 * This way MaxScale could try reloading users' just after startup
  		 */
-
 		service->rate_limit.last=time(NULL) - USERS_REFRESH_TIME;
 		service->rate_limit.nloads=1;
 
@@ -219,14 +237,21 @@ GWPROTOCOL	*funcs;
 			LOGFILE_MESSAGE,
 			"Loaded %d MySQL Users for service [%s].",
 			loaded, service->name)));
-	} else {
+	} 
+	else 
+	{
 		/* Generic users table */
 		service->users = users_alloc();
 	}
 
-	if ((funcs =
-             (GWPROTOCOL *)load_module(port->protocol, MODULE_PROTOCOL)) == NULL)
+	if ((funcs=(GWPROTOCOL *)load_module(port->protocol, MODULE_PROTOCOL)) 
+		== NULL)
 	{
+		if (service->users->data)
+		{
+			hashtable_free(service->users->data);
+		}
+		free(service->users);
 		dcb_free(port->listener);
 		port->listener = NULL;
 		LOGIF(LE, (skygw_log_write_flush(
@@ -235,34 +260,60 @@ GWPROTOCOL	*funcs;
                         "for service %s not started.",
 			port->protocol,
                         service->name)));
-		return 0;
+		goto retblock;
 	}
 	memcpy(&(port->listener->func), funcs, sizeof(GWPROTOCOL));
 	port->listener->session = NULL;
+	
 	if (port->address)
 		sprintf(config_bind, "%s:%d", port->address, port->port);
 	else
 		sprintf(config_bind, "0.0.0.0:%d", port->port);
 
-	if (port->listener->func.listen(port->listener, config_bind)) {
+	if (port->listener->func.listen(port->listener, config_bind)) 
+	{
                 port->listener->session = session_alloc(service, port->listener);
 
-                if (port->listener->session != NULL) {
+                if (port->listener->session != NULL) 
+		{
                         port->listener->session->state = SESSION_STATE_LISTENER;
                         listeners += 1;
-                } else {
+                } 
+                else 
+		{
+			LOGIF(LE, (skygw_log_write_flush(
+				LOGFILE_ERROR,
+				"Error : Failed to create session to service %s.",
+				service->name)));
+			
+			if (service->users->data)
+			{
+				hashtable_free(service->users->data);
+			}
+			free(service->users);
                         dcb_close(port->listener);
+			port->listener = NULL;
+			goto retblock;
                 }
-        } else {
-                dcb_close(port->listener);
-                
+        } 
+        else 
+	{       
                 LOGIF(LE, (skygw_log_write_flush(
                         LOGFILE_ERROR,
 			"Error : Unable to start to listen port %d for %s %s.",
 			port->port,
                         port->protocol,
                         service->name)));
+		if (service->users->data)
+		{
+			hashtable_free(service->users->data);
+		}
+		free(service->users);
+		dcb_close(port->listener);
+		port->listener = NULL;
         }
+        
+retblock:
 	return listeners;
 }
 

server/modules/routing/readwritesplit/readwritesplit.c

@@ -1898,6 +1898,10 @@ static int routeQuery(
 	/** Lock router session */
 	if (!rses_begin_locked_router_action(router_cli_ses))
 	{
+		LOGIF(LT, (skygw_log_write(
+			LOGFILE_TRACE,
+			"Route query aborted! Routing session is closed <")));
+		ret = 0;
 		goto retblock;
 	}
 	/**