drop metadata when drop sequence header. support PCUC 0x1a

trunk/src/protocol/srs_rtmp_stack.hpp

@@ -1991,6 +1991,13 @@ enum SrcPCUCEventType
     * kMsgPingRequest request.
     */
     SrcPCUCPingResponse             = 0x07,
+    
+    /**
+     * for PCUC size=3, the payload is "00 1A 01",
+     * where we think the event is 0x001a, fms defined msg,
+     * which has only 1bytes event data.
+     */
+    SrsPCUCFmsEvent0                = 0x1a,
 };
 
 /**
@@ -2019,6 +2026,11 @@ public:
     * @see: SrcPCUCEventType
     */
     int16_t event_type;
+    /**
+     * the event data generally in 4bytes.
+     * @remark for event type is 0x001a, only 1bytes.
+     * @see SrsPCUCFmsEvent0
+     */
     int32_t event_data;
     /**
     * 4bytes if event_type is SetBufferLength; otherwise 0.