When protocol closes DCB it calls dcb_close instead of dcb->func.close. dcb_close then calls dcb->func.close. This is now changed to all protocols and routers.

Rwsplit handles ERRACT_NEW_CONNECTION by clearing backend reference, removing callbacks and associating backend reference with new backend server. If it succeeds and the router session can continue, handleError returns true. Otherwise false. When ever false is returned it means that session must be closed.

Rwsplit now tolerates backend failures in a way that it searches new backends when monitor, backend, or client operation fails due to backend failure.

server/modules/include/mysql_client_server_protocol.h

@@ -265,6 +265,12 @@ int mysql_send_custom_error (
         int packet_number,
         int in_affected_rows,
         const char* mysql_message);
+
+GWBUF* mysql_create_custom_error(
+        int packet_number, 
+        int affected_rows,
+        const char* msg);
+
 int gw_send_change_user_to_backend(
         char *dbname,
         char *user,