1 /*
2 * Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include "call/rtcp_demuxer.h"
12
13 #include "call/rtcp_packet_sink_interface.h"
14 #include "call/rtp_rtcp_demuxer_helper.h"
15 #include "common_types.h" // NOLINT(build/include)
16 #include "rtc_base/checks.h"
17
18 namespace webrtc {
19
20 RtcpDemuxer::RtcpDemuxer() = default;
21
~RtcpDemuxer()22 RtcpDemuxer::~RtcpDemuxer() {
23 RTC_DCHECK(ssrc_sinks_.empty());
24 RTC_DCHECK(rsid_sinks_.empty());
25 RTC_DCHECK(broadcast_sinks_.empty());
26 }
27
AddSink(uint32_t sender_ssrc,RtcpPacketSinkInterface * sink)28 void RtcpDemuxer::AddSink(uint32_t sender_ssrc, RtcpPacketSinkInterface* sink) {
29 RTC_DCHECK(sink);
30 RTC_DCHECK(!ContainerHasKey(broadcast_sinks_, sink));
31 RTC_DCHECK(!MultimapAssociationExists(ssrc_sinks_, sender_ssrc, sink));
32 ssrc_sinks_.emplace(sender_ssrc, sink);
33 }
34
AddSink(const std::string & rsid,RtcpPacketSinkInterface * sink)35 void RtcpDemuxer::AddSink(const std::string& rsid,
36 RtcpPacketSinkInterface* sink) {
37 RTC_DCHECK(StreamId::IsLegalName(rsid));
38 RTC_DCHECK(sink);
39 RTC_DCHECK(!ContainerHasKey(broadcast_sinks_, sink));
40 RTC_DCHECK(!MultimapAssociationExists(rsid_sinks_, rsid, sink));
41 rsid_sinks_.emplace(rsid, sink);
42 }
43
AddBroadcastSink(RtcpPacketSinkInterface * sink)44 void RtcpDemuxer::AddBroadcastSink(RtcpPacketSinkInterface* sink) {
45 RTC_DCHECK(sink);
46 RTC_DCHECK(!MultimapHasValue(ssrc_sinks_, sink));
47 RTC_DCHECK(!MultimapHasValue(rsid_sinks_, sink));
48 RTC_DCHECK(!ContainerHasKey(broadcast_sinks_, sink));
49 broadcast_sinks_.push_back(sink);
50 }
51
RemoveSink(const RtcpPacketSinkInterface * sink)52 void RtcpDemuxer::RemoveSink(const RtcpPacketSinkInterface* sink) {
53 RTC_DCHECK(sink);
54 size_t removal_count = RemoveFromMultimapByValue(&ssrc_sinks_, sink) +
55 RemoveFromMultimapByValue(&rsid_sinks_, sink);
56 RTC_DCHECK_GT(removal_count, 0);
57 }
58
RemoveBroadcastSink(const RtcpPacketSinkInterface * sink)59 void RtcpDemuxer::RemoveBroadcastSink(const RtcpPacketSinkInterface* sink) {
60 RTC_DCHECK(sink);
61 auto it = std::find(broadcast_sinks_.begin(), broadcast_sinks_.end(), sink);
62 RTC_DCHECK(it != broadcast_sinks_.end());
63 broadcast_sinks_.erase(it);
64 }
65
OnRtcpPacket(rtc::ArrayView<const uint8_t> packet)66 void RtcpDemuxer::OnRtcpPacket(rtc::ArrayView<const uint8_t> packet) {
67 // Perform sender-SSRC-based demuxing for packets with a sender-SSRC.
68 rtc::Optional<uint32_t> sender_ssrc = ParseRtcpPacketSenderSsrc(packet);
69 if (sender_ssrc) {
70 auto it_range = ssrc_sinks_.equal_range(*sender_ssrc);
71 for (auto it = it_range.first; it != it_range.second; ++it) {
72 it->second->OnRtcpPacket(packet);
73 }
74 }
75
76 // All packets, even those without a sender-SSRC, are broadcast to sinks
77 // which listen to broadcasts.
78 for (RtcpPacketSinkInterface* sink : broadcast_sinks_) {
79 sink->OnRtcpPacket(packet);
80 }
81 }
82
OnSsrcBoundToRsid(const std::string & rsid,uint32_t ssrc)83 void RtcpDemuxer::OnSsrcBoundToRsid(const std::string& rsid, uint32_t ssrc) {
84 // Record the new SSRC association for all of the sinks that were associated
85 // with the RSID.
86 auto it_range = rsid_sinks_.equal_range(rsid);
87 for (auto it = it_range.first; it != it_range.second; ++it) {
88 RtcpPacketSinkInterface* sink = it->second;
89 // Watch out for pre-existing SSRC-based associations.
90 if (!MultimapAssociationExists(ssrc_sinks_, ssrc, sink)) {
91 AddSink(ssrc, sink);
92 }
93 }
94
95 // RSIDs are uniquely associated with SSRCs; no need to keep in memory
96 // the RSID-to-sink association of resolved RSIDs.
97 rsid_sinks_.erase(it_range.first, it_range.second);
98 }
99
100 } // namespace webrtc
101