Add discontinuity check in rfc3984 unpacker.

include/mediastreamer2/rfc3984.h

@@ -37,9 +37,10 @@ typedef struct Rfc3984Context{
 	mblk_t *m;
 	int maxsz;
 	uint32_t last_ts;
+	uint16_t ref_cseq;
 	uint8_t mode;
 	bool_t stap_a_allowed;
-	uint8_t reserved;
+	bool_t initialized_ref_cseq;
 } Rfc3984Context;
 
 MS2_PUBLIC Rfc3984Context *rfc3984_new(void);
@@ -55,8 +56,11 @@ MS2_PUBLIC void rfc3984_enable_stap_a(Rfc3984Context *ctx, bool_t yesno);
 /*process NALUs and pack them into rtp payloads */
 MS2_PUBLIC void rfc3984_pack(Rfc3984Context *ctx, MSQueue *naluq, MSQueue *rtpq, uint32_t ts);
 
-/*process incoming rtp data and output NALUs, whenever possible*/
-MS2_PUBLIC void rfc3984_unpack(Rfc3984Context *ctx, mblk_t *im, MSQueue *naluq);
+/**
+ * Process incoming rtp data and output NALUs, whenever possible.
+ * @return 0 if everything was ok, -1 on error.
+**/
+MS2_PUBLIC int rfc3984_unpack(Rfc3984Context *ctx, mblk_t *im, MSQueue *naluq);
 
 void rfc3984_uninit(Rfc3984Context *ctx);
 

src/voip/rfc3984.c

@@ -243,11 +243,13 @@ static mblk_t * aggregate_fua(Rfc3984Context *ctx, mblk_t *im){
 }
 
 /*process incoming rtp data and output NALUs, whenever possible*/
-void rfc3984_unpack(Rfc3984Context *ctx, mblk_t *im, MSQueue *out){
+int rfc3984_unpack(Rfc3984Context *ctx, mblk_t *im, MSQueue *out){
 	uint8_t type=nal_header_get_type(im->b_rptr);
 	uint8_t *p;
 	int marker = mblk_get_marker_info(im);
 	uint32_t ts=mblk_get_timestamp_info(im);
+	uint16_t cseq=mblk_get_cseq(im);
+	int res = 0;
 
 	if (ctx->last_ts!=ts){
 		/*a new frame is arriving, in case the marker bit was not set in previous frame, output it now*/
@@ -258,6 +260,7 @@ void rfc3984_unpack(Rfc3984Context *ctx, mblk_t *im, MSQueue *out){
 			while(!ms_queue_empty(&ctx->q)){
 				ms_queue_put(out,ms_queue_get(&ctx->q));
 				out_without_marker = TRUE;
+				res = -1;
 			}
 			if (out_without_marker) ms_warning("Incomplete H264 frame (missing marker bit)");
 		}
@@ -265,6 +268,18 @@ void rfc3984_unpack(Rfc3984Context *ctx, mblk_t *im, MSQueue *out){
 
 	if (im->b_cont) msgpullup(im,-1);
 
+	if (!ctx->initialized_ref_cseq) {
+		ctx->initialized_ref_cseq = TRUE;
+		ctx->ref_cseq = cseq;
+	} else {
+		ctx->ref_cseq++;
+		if (ctx->ref_cseq != cseq) {
+			ms_message("sequence inconsistency detected (diff=%i)",(int)(cseq - ctx->ref_cseq));
+			ctx->ref_cseq = cseq;
+			res = -1;
+		}
+	}
+
 	if (type==TYPE_STAP_A){
 		/*split into nalus*/
 		uint16_t sz;
@@ -312,6 +327,8 @@ void rfc3984_unpack(Rfc3984Context *ctx, mblk_t *im, MSQueue *out){
 			ms_queue_put(out,ms_queue_get(&ctx->q));
 		}
 	}
+
+	return res;
 }