Merge branch '2.3' into develop

include/maxscale/buffer.hh

@@ -45,6 +45,7 @@ enum gwbuf_type_t
     GWBUF_TYPE_RESULT         = (1 << 3),
     GWBUF_TYPE_REPLY_OK       = (1 << 4),
     GWBUF_TYPE_REPLAYED       = (1 << 5),
+    GWBUF_TYPE_TRACK_STATE    = (1 << 6),
 };
 
 #define GWBUF_IS_TYPE_UNDEFINED(b)     ((b)->gwbuf_type == 0)
@@ -56,6 +57,9 @@ enum gwbuf_type_t
 // True if the query is not initiated by the client but an internal replaying mechanism
 #define GWBUF_IS_REPLAYED(b)           ((b)->gwbuf_type & GWBUF_TYPE_REPLAYED)
 
+// Track session state change response
+#define GWBUF_SHOULD_TRACK_STATE(b) ((b)->gwbuf_type & GWBUF_TYPE_TRACK_STATE)
+
 enum  gwbuf_info_t
 {
     GWBUF_INFO_NONE   = 0x0,