fix #98: workaround for librtmp ping(fmt=1,cid=2 fresh stream).

@@ -231,6 +231,7 @@ Supported operating systems and hardware:
 * 2013-10-17, Created.<br/>
 
 ## History
+* v1.0, 2014-06-14, fix [#98](https://github.com/winlinvip/simple-rtmp-server/issues/98), workaround for librtmp ping(fmt=1,cid=2 fresh stream). 0.9.124
 * v1.0, 2014-05-29, support flv inject and flv http streaming with start=bytes. 0.9.122
 * <strong>v1.0, 2014-05-28, [1.0 mainline4(0.9.120)](https://github.com/winlinvip/simple-rtmp-server/releases/tag/1.0.mainline4) released. 39200 lines.</strong>
 * v1.0, 2014-05-27, fix [#87](https://github.com/winlinvip/simple-rtmp-server/issues/87), add source id for full trackable log. 0.9.120

@@ -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 "123"
+#define VERSION_REVISION "124"
 #define RTMP_SIG_SRS_VERSION VERSION_MAJOR"."VERSION_MINOR"."VERSION_REVISION
 // server info.
 #define RTMP_SIG_SRS_KEY "SRS"

@@ -954,10 +954,23 @@ int SrsProtocol::read_message_header(SrsChunkStream* chunk, char fmt, int bh_siz
     // but, we can ensure that when a chunk stream is fresh, 
     // the fmt must be 0, a new stream.
     if (chunk->msg_count == 0 && fmt != RTMP_FMT_TYPE0) {
-        ret = ERROR_RTMP_CHUNK_START;
-        srs_error("chunk stream is fresh, fmt must be %d, actual is %d. cid=%d, ret=%d", 
-            RTMP_FMT_TYPE0, fmt, chunk->cid, ret);
-        return ret;
+        // for librtmp, if ping, it will send a fresh stream with fmt=1,
+        // 0x42             where: fmt=1, cid=2, protocol contorl user-control message
+        // 0x00 0x00 0x00   where: timestamp=0
+        // 0x00 0x00 0x06   where: payload_length=6
+        // 0x04             where: message_type=4(protocol control user-control message)
+        // 0x00 0x06            where: event Ping(0x06)
+        // 0x00 0x00 0x0d 0x0f  where: event data 4bytes ping timestamp.
+        // @see: https://github.com/winlinvip/simple-rtmp-server/issues/98
+        if (chunk->cid == RTMP_CID_ProtocolControl && fmt == RTMP_FMT_TYPE1) {
+            srs_warn("accept cid=2, fmt=1 to make librtmp happy.");
+        } else {
+            // must be a RTMP protocol level error.
+            ret = ERROR_RTMP_CHUNK_START;
+            srs_error("chunk stream is fresh, fmt must be %d, actual is %d. cid=%d, ret=%d", 
+                RTMP_FMT_TYPE0, fmt, chunk->cid, ret);
+            return ret;
+        }
     }
 
     // when exists cache msg, means got an partial message,