P2P - Libdatachannel/RTC Library Files

2026-09-30 11:34:07 -07:00
parent 23f7abd778
commit 0d5ca59a8e
49 changed files with 4458 additions and 0 deletions
--- a/libdatachannel/include/rtc/rtcpreceivingsession.hpp
+++ b/libdatachannel/include/rtc/rtcpreceivingsession.hpp
@ -0,0 +1,95 @@
+/**
+ * Copyright (c) 2020 Staz Modrzynski
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#ifndef RTC_RTCP_RECEIVING_SESSION_H
+#define RTC_RTCP_RECEIVING_SESSION_H
+
+#if RTC_ENABLE_MEDIA
+
+#include "common.hpp"
+#include "description.hpp"
+#include "mediahandler.hpp"
+#include "message.hpp"
+#include "rtp.hpp"
+
+#include <atomic>
+#include <mutex>
+#include <unordered_map>
+#include <vector>
+
+#define RTP_SEQ_MOD (1<<16)
+
+namespace rtc {
+
+// An RtcpSession can be plugged into a Track to handle the whole RTCP session
+class RTC_CPP_EXPORT RtcpReceivingSession : public MediaHandler {
+public:
+	RtcpReceivingSession() = default;
+	virtual ~RtcpReceivingSession() = default;
+
+	void media(const Description::Media &desc) override;
+	void incoming(message_vector &messages, const message_callback &send) override;
+	bool requestKeyframe(const std::vector<SSRC>& targetSSRCs, bool retransmit, const message_callback &send) override;
+	bool requestBitrate(unsigned int bitrate, const message_callback &send) override;
+
+	// For backward compatibility
+	[[deprecated("Use Track::requestKeyframe()")]] inline bool requestKeyframe() { return false; };
+	[[deprecated("Use Track::requestBitrate()")]] inline void requestBitrate(unsigned int) {};
+
+	struct SyncTimestamps {
+		uint64_t rtpTimestamp;
+		uint64_t ntpTimestamp;
+	};
+
+	SyncTimestamps getSyncTimestamps();
+
+protected:
+	void pushREMB(const message_callback &send, unsigned int bitrate);
+	void pushRR(const message_callback &send,unsigned int lastSrDelay);
+	void pushPLI(const message_callback &send);
+	void pushFIR(const message_callback &send, const std::vector<SSRC>& targetSSRCs, bool retransmit);
+
+	void initSeq(uint16_t seq);
+	bool updateSeq(uint16_t seq);
+	
+	SSRC mSsrc = 0;
+	uint32_t mGreatestSeqNo = 0;
+    uint16_t mMaxSeq = 0;			// highest seq. number seen
+    uint32_t mCycles = 0;			// shifted count of seq. number cycles
+	uint32_t mBaseSeq = 0;			// base seq number
+    uint32_t mBadSeq = 0;			// last 'bad' seq number + 1
+	uint32_t mProbation = 0;		// sequ. packets till source is valid
+    uint32_t mReceived = 0;			// packets received
+    uint32_t mExpectedPrior = 0;	// packet expected at last interval
+    uint32_t mReceivedPrior = 0;	// packet received at last interval
+	uint32_t mTransit = 0;			// relative trans time for prev pkt
+	uint32_t mJitter = 0;	
+	
+	SyncTimestamps mSyncTimestamps{0,0};
+
+	std::atomic<unsigned int> mRequestedBitrate = 0;
+	std::mutex mSyncMutex;
+	std::mutex mMutex;
+
+	message_ptr unwrapRtx(const message_ptr &rtxPacket);
+
+	// RTX state populated by media() from SDP inspection
+	std::unordered_map<uint8_t, uint8_t> mRtxToPrimaryPtMap; // RTX PT -> primary PT
+	SSRC mRtxPrimarySsrc = 0;
+	bool mRtxEnabled = false;
+
+	bool mSupportsRfc5104Fir = false;
+	std::unordered_map<SSRC, uint32_t> mRfc5104FirCmdNums; // SSRC -> seq no mapping
+};
+
+} // namespace rtc
+
+#endif // RTC_ENABLE_MEDIA
+
+#endif // RTC_RTCP_RECEIVING_SESSION_H