Add RSID-based demuxing to RtpDemuxer
Make RtpDemuxer able to demux RTP packets according to RSID (RTP Stream ID), as well as the (pre-existing) ability to demux according to SSRC.
BUG=None
Review-Url: https://codereview.webrtc.org/2920993002
Cr-Commit-Position: refs/heads/master@{#18495}
diff --git a/webrtc/call/rtp_demuxer.h b/webrtc/call/rtp_demuxer.h
index 2c9b725..a5ba889 100644
--- a/webrtc/call/rtp_demuxer.h
+++ b/webrtc/call/rtp_demuxer.h
@@ -7,10 +7,13 @@
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
+
#ifndef WEBRTC_CALL_RTP_DEMUXER_H_
#define WEBRTC_CALL_RTP_DEMUXER_H_
#include <map>
+#include <set>
+#include <string>
namespace webrtc {
@@ -30,15 +33,43 @@
// Registers a sink. The same sink can be registered for multiple ssrcs, and
// the same ssrc can have multiple sinks. Null pointer is not allowed.
void AddSink(uint32_t ssrc, RtpPacketSinkInterface* sink);
- // Removes a sink. Returns deletion count (a sink may be registered
- // for multiple ssrcs). Null pointer is not allowed.
- size_t RemoveSink(const RtpPacketSinkInterface* sink);
+
+ // Registers a sink's association to an RSID. Null pointer is not allowed.
+ void AddSink(const std::string& rsid, RtpPacketSinkInterface* sink);
+
+ // Removes a sink. Return value reports if anything was actually removed.
+ // Null pointer is not allowed.
+ bool RemoveSink(const RtpPacketSinkInterface* sink);
// Returns true if at least one matching sink was found, otherwise false.
bool OnRtpPacket(const RtpPacketReceived& packet);
private:
+ // Records a sink<->SSRC association. This can happen by explicit
+ // configuration by AddSink(ssrc...), or by inferred configuration from an
+ // RSID-based configuration which is resolved to an SSRC upon
+ // packet reception.
+ void RecordSsrcToSinkAssociation(uint32_t ssrc, RtpPacketSinkInterface* sink);
+
+ // When a new packet arrives, we attempt to resolve extra associations,
+ // such as which RSIDs are associated with which SSRCs.
+ void FindSsrcAssociations(const RtpPacketReceived& packet);
+
+ // This records the association SSRCs to sinks. Other associations, such
+ // as by RSID, also end up here once the RSID, etc., is resolved to an SSRC.
std::multimap<uint32_t, RtpPacketSinkInterface*> sinks_;
+
+ // A sink may be associated with an RSID - RTP Stream ID. This tag has a
+ // one-to-one association with an SSRC, but that SSRC is not yet known.
+ // When it becomes known, the association of the sink to the RSID is deleted
+ // from this container, and moved into |sinks_|.
+ std::multimap<std::string, RtpPacketSinkInterface*> rsid_sinks_;
+
+ // Iterating over |rsid_sinks_| for each incoming and performing multiple
+ // string comparisons is of non-trivial cost. To avoid this cost, we only
+ // check RSIDs for the first packet on each incoming SSRC stream.
+ // (If RSID associations are added later, we check again.)
+ std::set<uint32_t> processed_ssrcs_;
};
} // namespace webrtc