finish basic protocol utest, fix the bug of fmt11 length error.

@@ -31,7 +31,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 // current release version
 #define VERSION_MAJOR "0"
 #define VERSION_MINOR "9"
-#define VERSION_REVISION "154"
+#define VERSION_REVISION "155"
 #define RTMP_SIG_SRS_VERSION VERSION_MAJOR"."VERSION_MINOR"."VERSION_REVISION
 // server info.
 #define RTMP_SIG_SRS_KEY "SRS"

@@ -1013,6 +1013,11 @@ int SrsProtocol::read_message_header(SrsChunkStream* chunk, char fmt, int bh_siz
     *   3bytes: payload length,     fmt=0,1
     *   1bytes: message type,       fmt=0,1
     *   4bytes: stream id,          fmt=0
+    * where:
+    *   fmt=0, 0x0X
+    *   fmt=1, 0x4X
+    *   fmt=2, 0x8X
+    *   fmt=3, 0xCX
     */
     // see also: ngx_rtmp_recv
     if (fmt <= RTMP_FMT_TYPE2) {
@@ -1060,21 +1065,25 @@ int SrsProtocol::read_message_header(SrsChunkStream* chunk, char fmt, int bh_siz
         }
         
         if (fmt <= RTMP_FMT_TYPE1) {
-            pp = (char*)&chunk->header.payload_length;
+            int32_t payload_length = 0;
+            pp = (char*)&payload_length;
             pp[2] = *p++;
             pp[1] = *p++;
             pp[0] = *p++;
             pp[3] = 0;
             
             // if msg exists in cache, the size must not changed.
-            if (chunk->msg->size > 0 && chunk->msg->size != chunk->header.payload_length) {
+            // always use the actual msg size, for the cache payload length can changed,
+            // for the fmt type1(stream_id not changed), user can change the payload length.
+            if (chunk->msg->size > 0 && chunk->header.payload_length != payload_length) {
                 ret = ERROR_RTMP_PACKET_SIZE;
                 srs_error("msg exists in chunk cache, "
                     "size=%d cannot change to %d, ret=%d", 
-                    chunk->msg->size, chunk->header.payload_length, ret);
+                    chunk->header.payload_length, payload_length, ret);
                 return ret;
             }
             
+            chunk->header.payload_length = payload_length;
             chunk->header.message_type = *p++;
             
             if (fmt == RTMP_FMT_TYPE0) {

@@ -256,23 +256,27 @@ class SrsMessageHeader
 {
 public:
     /**
-    * One byte field to represent the message type. A range of type IDs
-    * (1-7) are reserved for protocol control messages.
+    * 3bytes.
+    * Three-byte field that contains a timestamp delta of the message.
+    * The 4 bytes are packed in the big-endian order.
+    * @remark, only used for decoding message from chunk stream.
     */
-    int8_t message_type;
+    int32_t timestamp_delta;
     /**
+    * 3bytes.
     * Three-byte field that represents the size of the payload in bytes.
     * It is set in big-endian format.
     */
     int32_t payload_length;
     /**
-    * Three-byte field that contains a timestamp delta of the message.
-    * The 4 bytes are packed in the big-endian order.
-    * @remark, only used for decoding message from chunk stream.
+    * 1byte.
+    * One byte field to represent the message type. A range of type IDs
+    * (1-7) are reserved for protocol control messages.
     */
-    int32_t timestamp_delta;
+    int8_t message_type;
     /**
-    * Three-byte field that identifies the stream of the message. These
+    * 4bytes.
+    * Four-byte field that identifies the stream of the message. These
     * bytes are set in big-endian format.
     */
     int32_t stream_id;
@@ -379,12 +383,17 @@ public:
 // 4.2. Message Payload
 public:
     /**
-    * The other part which is the payload is the actual data that is
-    * contained in the message. For example, it could be some audio samples
-    * or compressed video data. The payload format and interpretation are
-    * beyond the scope of this document.
+    * current message parsed size,
+    *       size <= header.payload_length
+    * for the payload maybe sent in multiple chunks.
     */
     int32_t size;
+    /**
+    * the payload of message, the SrsMessage never know about the detail of payload,
+    * user must use SrsProtocol.decode_message to get concrete packet.
+    * @remark, not all message payload can be decoded to packet. for example, 
+    *       video/audio packet use raw bytes, no video/audio packet.
+    */
     int8_t* payload;
 protected:
     SrsMessage();