srs-librtmp: implements the read packet.

@@ -31,11 +31,16 @@ int main(int argc, char** argv)
 {
 	srs_rtmp_t rtmp;
 	
+	// packet data
+	int type, size;
+	u_int32_t timestamp;
+	char* data;
+	
     printf("suck rtmp stream like rtmpdump\n");
     printf("srs(simple-rtmp-server) client librtmp library.\n");
     printf("version: %d.%d.%d\n", srs_version_major(), srs_version_minor(), srs_version_revision());
     
-    rtmp = srs_rtmp_create("rtmp://127.0.0.1:1935/live/show?vhost=__defaultVhost__/livestream");
+    rtmp = srs_rtmp_create("rtmp://127.0.0.1:1935/live?vhost=__defaultVhost__/livestream");
     
  	if (srs_simple_handshake(rtmp) != 0) {
 		printf("simple handshake failed.\n");
@@ -55,6 +60,15 @@ int main(int argc, char** argv)
 	}
 	printf("play stream success\n");
 	
+	for (;;) {
+		if (srs_read_packet(rtmp, &type, &timestamp, &data, &size) != 0) {
+			goto rtmp_destroy;
+		}
+		printf("got packet: type=%s, time=%d, size=%d\n", srs_type2string(type), timestamp, size);
+		
+		free(data);
+	}
+	
 rtmp_destroy:
     srs_rtmp_destroy(rtmp);
     

@@ -33,6 +33,8 @@ using namespace std;
 #include <srs_lib_simple_socket.hpp>
 #include <srs_kernel_log.hpp>
 #include <srs_protocol_utility.hpp>
+#include <srs_core_autofree.hpp>
+#include <srs_protocol_rtmp_stack.hpp>
 
 // if user want to define log, define the folowing macro.
 #ifndef SRS_RTMP_USER_DEFINED_LOG
@@ -256,6 +258,79 @@ int srs_publish_stream(srs_rtmp_t rtmp)
 	return ret;
 }
 
+const char* srs_type2string(int type)
+{
+	switch (type) {
+		case SRS_RTMP_TYPE_AUDIO: return "Audio";
+		case SRS_RTMP_TYPE_VIDEO: return "Video";
+		case SRS_RTMP_TYPE_SCRIPT: return "Data";
+		default: return "Unknown";
+	}
+	
+	return "Unknown";
+}
+
+int srs_read_packet(srs_rtmp_t rtmp, int* type, u_int32_t* timestamp, char** data, int* size)
+{
+	*type = 0;
+	*timestamp = 0;
+	*data = NULL;
+	*size = 0;
+	
+	int ret = ERROR_SUCCESS;
+	
+    srs_assert(rtmp != NULL);
+    Context* context = (Context*)rtmp;
+    
+    for (;;) {
+        SrsCommonMessage* msg = NULL;
+        if ((ret = context->rtmp->recv_message(&msg)) != ERROR_SUCCESS) {
+            return ret;
+        }
+        if (!msg) {
+            continue;
+        }
+        
+        SrsAutoFree(SrsCommonMessage, msg, false);
+        
+        if (msg->header.is_audio()) {
+            *type = SRS_RTMP_TYPE_AUDIO;
+            *timestamp = (u_int32_t)msg->header.timestamp;
+            *data = (char*)msg->payload;
+            *size = (int)msg->size;
+            // detach bytes from packet.
+            msg->payload = NULL;
+        } else if (msg->header.is_video()) {
+            *type = SRS_RTMP_TYPE_VIDEO;
+            *timestamp = (u_int32_t)msg->header.timestamp;
+            *data = (char*)msg->payload;
+            *size = (int)msg->size;
+            // detach bytes from packet.
+            msg->payload = NULL;
+        } else if (msg->header.is_amf0_data() || msg->header.is_amf3_data()) {
+            *type = SRS_RTMP_TYPE_SCRIPT;
+            *data = (char*)msg->payload;
+            *size = (int)msg->size;
+            // detach bytes from packet.
+            msg->payload = NULL;
+        } else {
+            // ignore and continue
+            continue;
+        }
+        
+        // got expected message.
+        break;
+    }
+    
+	return ret;
+}
+
+int srs_write_packet(srs_rtmp_t rtmp, int type, u_int32_t timestamp, char* data, int size)
+{
+	int ret = ERROR_SUCCESS;
+	return ret;
+}
+
 int srs_ssl_enabled()
 {
 #ifndef SRS_SSL

@@ -28,6 +28,8 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <srs_librtmp.h>
 */
 
+#include <sys/types.h>
+
 /**
 * srs-librtmp is a librtmp like library,
 * used to play/publish rtmp stream from/to rtmp server.
@@ -101,6 +103,43 @@ int srs_play_stream(srs_rtmp_t rtmp);
 int srs_publish_stream(srs_rtmp_t rtmp);
 
 /**
+* E.4.1 FLV Tag, page 75
+*/
+// 8 = audio
+#define SRS_RTMP_TYPE_AUDIO 8
+// 9 = video
+#define SRS_RTMP_TYPE_VIDEO 9
+// 18 = script data
+#define SRS_RTMP_TYPE_SCRIPT 18
+/**
+* convert the flv tag type to string.
+* 	SRS_RTMP_TYPE_AUDIO to "Audio"
+* 	SRS_RTMP_TYPE_VIDEO to "Video"
+* 	SRS_RTMP_TYPE_SCRIPT to "Data"
+* 	otherwise, "Unknown"
+*/
+const char* srs_type2string(int type);
+/**
+* read a audio/video/script-data packet from rtmp stream.
+* @param type, output the packet type, macros:
+*			SRS_RTMP_TYPE_AUDIO, FlvTagAudio
+*			SRS_RTMP_TYPE_VIDEO, FlvTagVideo
+*			SRS_RTMP_TYPE_SCRIPT, FlvTagScript
+* @param timestamp, in ms, overflow in 50days
+* @param data, the packet data, according to type:
+* 			FlvTagAudio, @see "E.4.2.1 AUDIODATA"
+*			FlvTagVideo, @see "E.4.3.1 VIDEODATA"
+*			FlvTagScript, @see "E.4.4.1 SCRIPTDATA"
+* @param size, size of packet.
+* @return the error code. 0 for success; otherwise, error.
+*
+* @remark: for read, user must free the data.
+* @remark: for write, user should never free the data, even if error.
+*/
+int srs_read_packet(srs_rtmp_t rtmp, int* type, u_int32_t* timestamp, char** data, int* size);
+int srs_write_packet(srs_rtmp_t rtmp, int type, u_int32_t timestamp, char* data, int size);
+
+/**
 * whether srs is compiled with ssl,
 * that is, compile srs with ssl: ./configure --with-ssl,.
 * if no ssl, complex handshake always error.

@@ -1025,6 +1025,14 @@ int SrsProtocol::read_message_header(SrsChunkStream* chunk, char fmt, int bh_siz
 
 		// ffmpeg/librtmp may donot send this filed, need to detect the value.
 		// @see also: http://blog.csdn.net/win_lin/article/details/13363699
+		// the extended-timestamp must be unsigned-int,
+		// 		24bits timestamp: 0xffffff = 16777215ms = 16777.215s = 4.66h
+		// 		32bits timestamp: 0xffffffff = 4294967295ms = 4294967.295s = 1193.046h = 49.71d
+		// because the rtmp protocol says the 32bits timestamp is about "50 days":
+		// 		3. Byte Order, Alignment, and Time Format
+		//				Because timestamps are generally only 32 bits long, they will roll
+		//				over after fewer than 50 days.
+		// so, use u_int32_t is right.
 		u_int32_t timestamp = 0x00;
         char* pp = (char*)&timestamp;
         pp[3] = *p++;