drop metadata when drop sequence header. support PCUC 0x1a

@@ -1463,7 +1463,11 @@ int SrsSource::on_meta_data(SrsCommonMessage* msg, SrsOnMetaDataPacket* metadata
     srs_verbose("initialize shared ptr metadata success.");
     
     // copy to all consumer
-    if (true) {
+    bool drop_for_reduce = false;
+    if (cache_metadata && _srs_config->get_reduce_sequence_header(_req->vhost)) {
+        drop_for_reduce = true;
+    }
+    if (!drop_for_reduce) {
         std::vector<SrsConsumer*>::iterator it;
         for (it = consumers.begin(); it != consumers.end(); ++it) {
             SrsConsumer* consumer = *it;
@@ -2084,10 +2088,10 @@ void SrsSource::on_unpublish()
     hds->on_unpublish();
 #endif
 
-    // only clear the gop cache metadata,
-    // donot clear the sequence header, for it maybe not changed.
+    // only clear the gop cache,
+    // donot clear the sequence header, for it maybe not changed,
+    // when drop dup sequence header, drop the metadata also.
     gop_cache->clear();
-    srs_freep(cache_metadata);
     
     srs_info("clear cache/metadata when unpublish.");
     srs_trace("cleanup when unpublish");

@@ -4240,10 +4240,22 @@ int SrsPlayPacket::get_message_type()
 
 int SrsPlayPacket::get_size()
 {
-    return SrsAmf0Size::str(command_name) + SrsAmf0Size::number()
-        + SrsAmf0Size::null() + SrsAmf0Size::str(stream_name)
-        + SrsAmf0Size::number() + SrsAmf0Size::number()
-        + SrsAmf0Size::boolean();
+    int size = SrsAmf0Size::str(command_name) + SrsAmf0Size::number()
+        + SrsAmf0Size::null() + SrsAmf0Size::str(stream_name);
+    
+    if (start != -2 || duration != -1 || !reset) {
+        size += SrsAmf0Size::number();
+    }
+    
+    if (duration != -1 || !reset) {
+        size += SrsAmf0Size::number();
+    }
+    
+    if (!reset) {
+        size += SrsAmf0Size::boolean();
+    }
+    
+    return size;
 }
 
 int SrsPlayPacket::encode_packet(SrsStream* stream)
@@ -4274,19 +4286,19 @@ int SrsPlayPacket::encode_packet(SrsStream* stream)
     }
     srs_verbose("encode stream_name success.");
     
-    if ((ret = srs_amf0_write_number(stream, start)) != ERROR_SUCCESS) {
+    if ((start != -2 || duration != -1 || !reset) && (ret = srs_amf0_write_number(stream, start)) != ERROR_SUCCESS) {
         srs_error("encode start failed. ret=%d", ret);
         return ret;
     }
     srs_verbose("encode start success.");
     
-    if ((ret = srs_amf0_write_number(stream, duration)) != ERROR_SUCCESS) {
+    if ((duration != -1 || !reset) && (ret = srs_amf0_write_number(stream, duration)) != ERROR_SUCCESS) {
         srs_error("encode duration failed. ret=%d", ret);
         return ret;
     }
     srs_verbose("encode duration success.");
     
-    if ((ret = srs_amf0_write_boolean(stream, reset)) != ERROR_SUCCESS) {
+    if (!reset && (ret = srs_amf0_write_boolean(stream, reset)) != ERROR_SUCCESS) {
         srs_error("encode reset failed. ret=%d", ret);
         return ret;
     }
@@ -5117,14 +5129,29 @@ int SrsUserControlPacket::decode(SrsStream* stream)
 {
     int ret = ERROR_SUCCESS;
     
-    if (!stream->require(6)) {
+    if (!stream->require(2)) {
         ret = ERROR_RTMP_MESSAGE_DECODE;
         srs_error("decode user control failed. ret=%d", ret);
         return ret;
     }
     
     event_type = stream->read_2bytes();
-    event_data = stream->read_4bytes();
+    
+    if (event_type == SrsPCUCFmsEvent0) {
+        if (!stream->require(1)) {
+            ret = ERROR_RTMP_MESSAGE_DECODE;
+            srs_error("decode user control failed. ret=%d", ret);
+            return ret;
+        }
+        event_data = stream->read_1bytes();
+    } else {
+        if (!stream->require(4)) {
+            ret = ERROR_RTMP_MESSAGE_DECODE;
+            srs_error("decode user control failed. ret=%d", ret);
+            return ret;
+        }
+        event_data = stream->read_4bytes();
+    }
     
     if (event_type == SrcPCUCSetBufferLength) {
         if (!stream->require(4)) {
@@ -5154,11 +5181,19 @@ int SrsUserControlPacket::get_message_type()
 
 int SrsUserControlPacket::get_size()
 {
-    if (event_type == SrcPCUCSetBufferLength) {
-        return 2 + 4 + 4;
+    int size = 2;
+    
+    if (event_type == SrsPCUCFmsEvent0) {
+        size += 1;
     } else {
-        return 2 + 4;
+        size += 4;
+    }
+    
+    if (event_type == SrcPCUCSetBufferLength) {
+        size += 4;
     }
+    
+    return size;
 }
 
 int SrsUserControlPacket::encode_packet(SrsStream* stream)
@@ -5172,7 +5207,12 @@ int SrsUserControlPacket::encode_packet(SrsStream* stream)
     }
     
     stream->write_2bytes(event_type);
-    stream->write_4bytes(event_data);
+    
+    if (event_type == SrsPCUCFmsEvent0) {
+        stream->write_1bytes(event_data);
+    } else {
+        stream->write_4bytes(event_data);
+    }
 
     // when event type is set buffer length,
     // write the extra buffer length.

@@ -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.