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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 01:47:29 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 01:47:29 +0000 |
commit | 0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d (patch) | |
tree | a31f07c9bcca9d56ce61e9a1ffd30ef350d513aa /dom/media/webrtc/jsep/JsepTrack.cpp | |
parent | Initial commit. (diff) | |
download | firefox-esr-upstream/115.8.0esr.tar.xz firefox-esr-upstream/115.8.0esr.zip |
Adding upstream version 115.8.0esr.upstream/115.8.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | dom/media/webrtc/jsep/JsepTrack.cpp | 670 |
1 files changed, 670 insertions, 0 deletions
diff --git a/dom/media/webrtc/jsep/JsepTrack.cpp b/dom/media/webrtc/jsep/JsepTrack.cpp new file mode 100644 index 0000000000..f60e4ce0d7 --- /dev/null +++ b/dom/media/webrtc/jsep/JsepTrack.cpp @@ -0,0 +1,670 @@ +/* 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 http://mozilla.org/MPL/2.0/. */ + +#include "jsep/JsepTrack.h" +#include "jsep/JsepCodecDescription.h" +#include "jsep/JsepTrackEncoding.h" + +#include <algorithm> + +namespace mozilla { +void JsepTrack::GetNegotiatedPayloadTypes( + std::vector<uint16_t>* payloadTypes) const { + if (!mNegotiatedDetails) { + return; + } + + for (const auto& encoding : mNegotiatedDetails->mEncodings) { + GetPayloadTypes(encoding->GetCodecs(), payloadTypes); + } + + // Prune out dupes + std::sort(payloadTypes->begin(), payloadTypes->end()); + auto newEnd = std::unique(payloadTypes->begin(), payloadTypes->end()); + payloadTypes->erase(newEnd, payloadTypes->end()); +} + +/* static */ +void JsepTrack::GetPayloadTypes( + const std::vector<UniquePtr<JsepCodecDescription>>& codecs, + std::vector<uint16_t>* payloadTypes) { + for (const auto& codec : codecs) { + uint16_t pt; + if (!codec->GetPtAsInt(&pt)) { + MOZ_ASSERT(false); + continue; + } + payloadTypes->push_back(pt); + } +} + +void JsepTrack::EnsureNoDuplicatePayloadTypes( + std::vector<UniquePtr<JsepCodecDescription>>* codecs) { + std::set<std::string> uniquePayloadTypes; + for (auto& codec : *codecs) { + codec->EnsureNoDuplicatePayloadTypes(uniquePayloadTypes); + } +} + +void JsepTrack::EnsureSsrcs(SsrcGenerator& ssrcGenerator, size_t aNumber) { + while (mSsrcs.size() < aNumber) { + uint32_t ssrc, rtxSsrc; + if (!ssrcGenerator.GenerateSsrc(&ssrc) || + !ssrcGenerator.GenerateSsrc(&rtxSsrc)) { + return; + } + mSsrcs.push_back(ssrc); + mSsrcToRtxSsrc[ssrc] = rtxSsrc; + MOZ_ASSERT(mSsrcs.size() == mSsrcToRtxSsrc.size()); + } +} + +void JsepTrack::PopulateCodecs( + const std::vector<UniquePtr<JsepCodecDescription>>& prototype) { + mPrototypeCodecs.clear(); + for (const auto& prototypeCodec : prototype) { + if (prototypeCodec->Type() == mType) { + mPrototypeCodecs.emplace_back(prototypeCodec->Clone()); + mPrototypeCodecs.back()->mDirection = mDirection; + } + } + + EnsureNoDuplicatePayloadTypes(&mPrototypeCodecs); +} + +void JsepTrack::AddToOffer(SsrcGenerator& ssrcGenerator, + SdpMediaSection* offer) { + AddToMsection(mPrototypeCodecs, offer); + + if (mDirection == sdp::kSend) { + std::vector<std::string> rids; + if (offer->IsSending()) { + rids = mRids; + } + + AddToMsection(rids, sdp::kSend, ssrcGenerator, + IsRtxEnabled(mPrototypeCodecs), offer); + } +} + +void JsepTrack::AddToAnswer(const SdpMediaSection& offer, + SsrcGenerator& ssrcGenerator, + SdpMediaSection* answer) { + // We do not modify mPrototypeCodecs here, since we're only creating an + // answer. Once offer/answer concludes, we will update mPrototypeCodecs. + std::vector<UniquePtr<JsepCodecDescription>> codecs = + NegotiateCodecs(offer, true, Nothing()); + if (codecs.empty()) { + return; + } + + AddToMsection(codecs, answer); + + if (mDirection == sdp::kSend) { + AddToMsection(mRids, sdp::kSend, ssrcGenerator, IsRtxEnabled(codecs), + answer); + } +} + +void JsepTrack::SetRids(const std::vector<std::string>& aRids) { + MOZ_ASSERT(!aRids.empty()); + if (!mRids.empty()) { + return; + } + mRids = aRids; +} + +void JsepTrack::SetMaxEncodings(size_t aMax) { + mMaxEncodings = aMax; + if (mRids.size() > mMaxEncodings) { + mRids.resize(mMaxEncodings); + } +} + +void JsepTrack::RecvTrackSetRemote(const Sdp& aSdp, + const SdpMediaSection& aMsection) { + mInHaveRemote = true; + MOZ_ASSERT(mDirection == sdp::kRecv); + MOZ_ASSERT(aMsection.GetMediaType() != + SdpMediaSection::MediaType::kApplication); + std::string error; + SdpHelper helper(&error); + + mRemoteSetSendBit = aMsection.IsSending(); + if (!mRemoteSetSendBit) { + mReceptive = false; + } + + if (aMsection.IsSending()) { + (void)helper.GetIdsFromMsid(aSdp, aMsection, &mStreamIds); + } else { + mStreamIds.clear(); + } + + // We do this whether or not the track is active + SetCNAME(helper.GetCNAME(aMsection)); + mSsrcs.clear(); + if (aMsection.GetAttributeList().HasAttribute(SdpAttribute::kSsrcAttribute)) { + for (const auto& ssrcAttr : aMsection.GetAttributeList().GetSsrc().mSsrcs) { + mSsrcs.push_back(ssrcAttr.ssrc); + } + } + + // Use FID ssrc-group to associate rtx ssrcs with "regular" ssrcs. Despite + // not being part of RFC 4588, this is how rtx is negotiated by libwebrtc + // and jitsi. + mSsrcToRtxSsrc.clear(); + if (aMsection.GetAttributeList().HasAttribute( + SdpAttribute::kSsrcGroupAttribute)) { + for (const auto& group : + aMsection.GetAttributeList().GetSsrcGroup().mSsrcGroups) { + if (group.semantics == SdpSsrcGroupAttributeList::kFid && + group.ssrcs.size() == 2) { + // Ensure we have a "regular" ssrc for each rtx ssrc. + if (std::find(mSsrcs.begin(), mSsrcs.end(), group.ssrcs[0]) != + mSsrcs.end()) { + mSsrcToRtxSsrc[group.ssrcs[0]] = group.ssrcs[1]; + + // Remove rtx ssrcs from mSsrcs + auto res = std::remove_if( + mSsrcs.begin(), mSsrcs.end(), + [group](uint32_t ssrc) { return ssrc == group.ssrcs[1]; }); + mSsrcs.erase(res, mSsrcs.end()); + } + } + } + } +} + +void JsepTrack::RecvTrackSetLocal(const SdpMediaSection& aMsection) { + MOZ_ASSERT(mDirection == sdp::kRecv); + + // TODO: Should more stuff live in here? Anything that needs to happen when we + // decide we're ready to receive packets should probably go in here. + mReceptive = aMsection.IsReceiving(); +} + +void JsepTrack::SendTrackSetRemote(SsrcGenerator& aSsrcGenerator, + const SdpMediaSection& aRemoteMsection) { + mInHaveRemote = true; + if (mType == SdpMediaSection::kApplication) { + return; + } + + std::vector<SdpRidAttributeList::Rid> rids; + + // TODO: Current language in webrtc-pc is completely broken, and so I will + // not be quoting it here. + if ((mType == SdpMediaSection::kVideo) && + aRemoteMsection.GetAttributeList().HasAttribute( + SdpAttribute::kSimulcastAttribute)) { + // Note: webrtc-pc does not appear to support the full IETF simulcast + // spec. In particular, the IETF simulcast spec supports requesting + // multiple different sets of encodings. For example, "a=simulcast:send + // 1,2;3,4;5,6" means that there are three simulcast streams, the first of + // which can use either rid 1 or 2 (but not both), the second of which can + // use rid 3 or 4 (but not both), and the third of which can use rid 5 or + // 6 (but not both). webrtc-pc does not support this either/or stuff for + // rid; each simulcast stream gets exactly one rid. + // Also, webrtc-pc does not support the '~' pause syntax at all + // See https://github.com/w3c/webrtc-pc/issues/2769 + GetRids(aRemoteMsection, sdp::kRecv, &rids); + } + + if (mRids.empty()) { + // Initial configuration + for (const auto& ridAttr : rids) { + // TODO: Spec might change, making a length > 16 invalid SDP. + std::string dummy; + if (SdpRidAttributeList::CheckRidValidity(ridAttr.id, &dummy) && + ridAttr.id.size() <= SdpRidAttributeList::kMaxRidLength) { + mRids.push_back(ridAttr.id); + } + } + if (mRids.size() > mMaxEncodings) { + mRids.resize(mMaxEncodings); + } + } else { + // JSEP is allowed to remove or reorder rids. RTCRtpSender won't pay + // attention to reordering. + std::vector<std::string> newRids; + for (const auto& ridAttr : rids) { + for (const auto& oldRid : mRids) { + if (oldRid == ridAttr.id) { + newRids.push_back(oldRid); + break; + } + } + } + mRids = std::move(newRids); + } + + if (mRids.empty()) { + mRids.push_back(""); + } + + UpdateSsrcs(aSsrcGenerator, mRids.size()); +} + +void JsepTrack::AddToMsection( + const std::vector<UniquePtr<JsepCodecDescription>>& codecs, + SdpMediaSection* msection) const { + MOZ_ASSERT(msection->GetMediaType() == mType); + MOZ_ASSERT(!codecs.empty()); + + for (const auto& codec : codecs) { + codec->AddToMediaSection(*msection); + } + + if ((mDirection == sdp::kSend) && (mType != SdpMediaSection::kApplication) && + msection->IsSending()) { + if (mStreamIds.empty()) { + msection->AddMsid("-", mTrackId); + } else { + for (const std::string& streamId : mStreamIds) { + msection->AddMsid(streamId, mTrackId); + } + } + } +} + +void JsepTrack::UpdateSsrcs(SsrcGenerator& ssrcGenerator, size_t encodings) { + MOZ_ASSERT(mDirection == sdp::kSend); + MOZ_ASSERT(mType != SdpMediaSection::kApplication); + size_t numSsrcs = std::max<size_t>(encodings, 1U); + + EnsureSsrcs(ssrcGenerator, numSsrcs); + PruneSsrcs(numSsrcs); + if (mNegotiatedDetails && mNegotiatedDetails->GetEncodingCount() > numSsrcs) { + mNegotiatedDetails->TruncateEncodings(numSsrcs); + } + + MOZ_ASSERT(!mSsrcs.empty()); +} + +void JsepTrack::PruneSsrcs(size_t aNumSsrcs) { + mSsrcs.resize(aNumSsrcs); + + // We might have duplicate entries in mSsrcs, so we need to resize first and + // then remove ummatched rtx ssrcs. + auto itor = mSsrcToRtxSsrc.begin(); + while (itor != mSsrcToRtxSsrc.end()) { + if (std::find(mSsrcs.begin(), mSsrcs.end(), itor->first) == mSsrcs.end()) { + itor = mSsrcToRtxSsrc.erase(itor); + } else { + ++itor; + } + } +} + +bool JsepTrack::IsRtxEnabled( + const std::vector<UniquePtr<JsepCodecDescription>>& codecs) const { + for (const auto& codec : codecs) { + if (codec->Type() == SdpMediaSection::kVideo && + static_cast<const JsepVideoCodecDescription*>(codec.get()) + ->mRtxEnabled) { + return true; + } + } + + return false; +} + +void JsepTrack::AddToMsection(const std::vector<std::string>& aRids, + sdp::Direction direction, + SsrcGenerator& ssrcGenerator, bool rtxEnabled, + SdpMediaSection* msection) { + if (aRids.size() > 1) { + UniquePtr<SdpSimulcastAttribute> simulcast(new SdpSimulcastAttribute); + UniquePtr<SdpRidAttributeList> ridAttrs(new SdpRidAttributeList); + for (const std::string& rid : aRids) { + SdpRidAttributeList::Rid ridAttr; + ridAttr.id = rid; + ridAttr.direction = direction; + ridAttrs->mRids.push_back(ridAttr); + + SdpSimulcastAttribute::Version version; + version.choices.push_back(SdpSimulcastAttribute::Encoding(rid, false)); + if (direction == sdp::kSend) { + simulcast->sendVersions.push_back(version); + } else { + simulcast->recvVersions.push_back(version); + } + } + + msection->GetAttributeList().SetAttribute(simulcast.release()); + msection->GetAttributeList().SetAttribute(ridAttrs.release()); + } + + bool requireRtxSsrcs = rtxEnabled && msection->IsSending(); + + if (mType != SdpMediaSection::kApplication && mDirection == sdp::kSend) { + UpdateSsrcs(ssrcGenerator, aRids.size()); + + if (requireRtxSsrcs) { + MOZ_ASSERT(mSsrcs.size() == mSsrcToRtxSsrc.size()); + std::vector<uint32_t> allSsrcs; + UniquePtr<SdpSsrcGroupAttributeList> group(new SdpSsrcGroupAttributeList); + for (const auto& ssrc : mSsrcs) { + const auto rtxSsrc = mSsrcToRtxSsrc[ssrc]; + allSsrcs.push_back(ssrc); + allSsrcs.push_back(rtxSsrc); + group->PushEntry(SdpSsrcGroupAttributeList::kFid, {ssrc, rtxSsrc}); + } + msection->SetSsrcs(allSsrcs, mCNAME); + msection->GetAttributeList().SetAttribute(group.release()); + } else { + msection->SetSsrcs(mSsrcs, mCNAME); + } + } +} + +void JsepTrack::GetRids(const SdpMediaSection& msection, + sdp::Direction direction, + std::vector<SdpRidAttributeList::Rid>* rids) const { + rids->clear(); + if (!msection.GetAttributeList().HasAttribute( + SdpAttribute::kSimulcastAttribute)) { + return; + } + + const SdpSimulcastAttribute& simulcast( + msection.GetAttributeList().GetSimulcast()); + + const SdpSimulcastAttribute::Versions* versions = nullptr; + switch (direction) { + case sdp::kSend: + versions = &simulcast.sendVersions; + break; + case sdp::kRecv: + versions = &simulcast.recvVersions; + break; + } + + if (!versions->IsSet()) { + return; + } + + // RFC 8853 does not seem to forbid duplicate rids in a simulcast attribute. + // So, while this is obviously silly, we should be prepared for it and + // ignore those duplicate rids. + std::set<std::string> uniqueRids; + for (const SdpSimulcastAttribute::Version& version : *versions) { + if (!version.choices.empty() && !uniqueRids.count(version.choices[0].rid)) { + // We validate that rids are present (and sane) elsewhere. + rids->push_back(*msection.FindRid(version.choices[0].rid)); + uniqueRids.insert(version.choices[0].rid); + } + } +} + +void JsepTrack::CreateEncodings( + const SdpMediaSection& remote, + const std::vector<UniquePtr<JsepCodecDescription>>& negotiatedCodecs, + JsepTrackNegotiatedDetails* negotiatedDetails) { + negotiatedDetails->mTias = remote.GetBandwidth("TIAS"); + + webrtc::RtcpMode rtcpMode = webrtc::RtcpMode::kCompound; + // rtcp-rsize (video only) + if (remote.GetMediaType() == SdpMediaSection::kVideo && + remote.GetAttributeList().HasAttribute( + SdpAttribute::kRtcpRsizeAttribute)) { + rtcpMode = webrtc::RtcpMode::kReducedSize; + } + negotiatedDetails->mRtpRtcpConf = RtpRtcpConfig(rtcpMode); + + // TODO add support for b=AS if TIAS is not set (bug 976521) + + if (mRids.empty()) { + mRids.push_back(""); + } + + size_t numEncodings = mRids.size(); + + // Drop SSRCs if fewer RIDs were offered than we have encodings + if (mSsrcs.size() > numEncodings) { + PruneSsrcs(numEncodings); + } + + // For each stream make sure we have an encoding, and configure + // that encoding appropriately. + for (size_t i = 0; i < numEncodings; ++i) { + UniquePtr<JsepTrackEncoding> encoding(new JsepTrackEncoding); + if (mRids.size() > i) { + encoding->mRid = mRids[i]; + } + for (const auto& codec : negotiatedCodecs) { + encoding->AddCodec(*codec); + } + negotiatedDetails->mEncodings.push_back(std::move(encoding)); + } +} + +std::vector<UniquePtr<JsepCodecDescription>> JsepTrack::GetCodecClones() const { + std::vector<UniquePtr<JsepCodecDescription>> clones; + for (const auto& codec : mPrototypeCodecs) { + clones.emplace_back(codec->Clone()); + } + return clones; +} + +static bool CompareCodec(const UniquePtr<JsepCodecDescription>& lhs, + const UniquePtr<JsepCodecDescription>& rhs) { + return lhs->mStronglyPreferred && !rhs->mStronglyPreferred; +} + +std::vector<UniquePtr<JsepCodecDescription>> JsepTrack::NegotiateCodecs( + const SdpMediaSection& remote, bool remoteIsOffer, + Maybe<const SdpMediaSection&> local) { + std::vector<UniquePtr<JsepCodecDescription>> negotiatedCodecs; + std::vector<UniquePtr<JsepCodecDescription>> newPrototypeCodecs; + + // Outer loop establishes the remote side's preference + for (const std::string& fmt : remote.GetFormats()) { + for (auto& codec : mPrototypeCodecs) { + if (!codec || !codec->mEnabled || !codec->Matches(fmt, remote)) { + continue; + } + + // First codec of ours that matches. See if we can negotiate it. + UniquePtr<JsepCodecDescription> clone(codec->Clone()); + if (clone->Negotiate(fmt, remote, remoteIsOffer, local)) { + // If negotiation succeeded, remember the payload type the other side + // used for reoffers. + codec->mDefaultPt = fmt; + + // Remember whether we negotiated rtx and the associated pt for later. + if (codec->Type() == SdpMediaSection::kVideo) { + JsepVideoCodecDescription* videoCodec = + static_cast<JsepVideoCodecDescription*>(codec.get()); + JsepVideoCodecDescription* cloneVideoCodec = + static_cast<JsepVideoCodecDescription*>(clone.get()); + bool useRtx = + mRtxIsAllowed && + Preferences::GetBool("media.peerconnection.video.use_rtx", false); + videoCodec->mRtxEnabled = useRtx && cloneVideoCodec->mRtxEnabled; + videoCodec->mRtxPayloadType = cloneVideoCodec->mRtxPayloadType; + } + + // Moves the codec out of mPrototypeCodecs, leaving an empty + // UniquePtr, so we don't use it again. Also causes successfully + // negotiated codecs to be placed up front in the future. + newPrototypeCodecs.emplace_back(std::move(codec)); + negotiatedCodecs.emplace_back(std::move(clone)); + break; + } + } + } + + // newPrototypeCodecs contains just the negotiated stuff so far. Add the rest. + for (auto& codec : mPrototypeCodecs) { + if (codec) { + newPrototypeCodecs.emplace_back(std::move(codec)); + } + } + + // Negotiated stuff is up front, so it will take precedence when ensuring + // there are no duplicate payload types. + EnsureNoDuplicatePayloadTypes(&newPrototypeCodecs); + std::swap(newPrototypeCodecs, mPrototypeCodecs); + + // Find the (potential) red codec and ulpfec codec or telephone-event + JsepVideoCodecDescription* red = nullptr; + JsepVideoCodecDescription* ulpfec = nullptr; + JsepAudioCodecDescription* dtmf = nullptr; + // We can safely cast here since JsepTrack has a MediaType and only codecs + // that match that MediaType (kAudio or kVideo) are added. + for (auto& codec : negotiatedCodecs) { + if (codec->mName == "red") { + red = static_cast<JsepVideoCodecDescription*>(codec.get()); + } else if (codec->mName == "ulpfec") { + ulpfec = static_cast<JsepVideoCodecDescription*>(codec.get()); + } else if (codec->mName == "telephone-event") { + dtmf = static_cast<JsepAudioCodecDescription*>(codec.get()); + } + } + // if we have a red codec remove redundant encodings that don't exist + if (red) { + // Since we could have an externally specified redundant endcodings + // list, we shouldn't simply rebuild the redundant encodings list + // based on the current list of codecs. + std::vector<uint8_t> unnegotiatedEncodings; + std::swap(unnegotiatedEncodings, red->mRedundantEncodings); + for (auto redundantPt : unnegotiatedEncodings) { + std::string pt = std::to_string(redundantPt); + for (const auto& codec : negotiatedCodecs) { + if (pt == codec->mDefaultPt) { + red->mRedundantEncodings.push_back(redundantPt); + break; + } + } + } + } + // Video FEC is indicated by the existence of the red and ulpfec + // codecs and not an attribute on the particular video codec (like in + // a rtcpfb attr). If we see both red and ulpfec codecs, we enable FEC + // on all the other codecs. + if (red && ulpfec) { + for (auto& codec : negotiatedCodecs) { + if (codec->mName != "red" && codec->mName != "ulpfec") { + JsepVideoCodecDescription* videoCodec = + static_cast<JsepVideoCodecDescription*>(codec.get()); + videoCodec->EnableFec(red->mDefaultPt, ulpfec->mDefaultPt); + } + } + } + + // Dtmf support is indicated by the existence of the telephone-event + // codec, and not an attribute on the particular audio codec (like in a + // rtcpfb attr). If we see the telephone-event codec, we enabled dtmf + // support on all the other audio codecs. + if (dtmf) { + for (auto& codec : negotiatedCodecs) { + JsepAudioCodecDescription* audioCodec = + static_cast<JsepAudioCodecDescription*>(codec.get()); + audioCodec->mDtmfEnabled = true; + } + } + + // Make sure strongly preferred codecs are up front, overriding the remote + // side's preference. + std::stable_sort(negotiatedCodecs.begin(), negotiatedCodecs.end(), + CompareCodec); + + if (!red) { + // No red, remove ulpfec + negotiatedCodecs.erase( + std::remove_if(negotiatedCodecs.begin(), negotiatedCodecs.end(), + [ulpfec](const UniquePtr<JsepCodecDescription>& codec) { + return codec.get() == ulpfec; + }), + negotiatedCodecs.end()); + // Make sure there's no dangling ptr here + ulpfec = nullptr; + } + + return negotiatedCodecs; +} + +nsresult JsepTrack::Negotiate(const SdpMediaSection& answer, + const SdpMediaSection& remote, + const SdpMediaSection& local) { + std::vector<UniquePtr<JsepCodecDescription>> negotiatedCodecs = + NegotiateCodecs(remote, &answer != &remote, SomeRef(local)); + + if (negotiatedCodecs.empty()) { + return NS_ERROR_FAILURE; + } + + UniquePtr<JsepTrackNegotiatedDetails> negotiatedDetails = + MakeUnique<JsepTrackNegotiatedDetails>(); + + CreateEncodings(remote, negotiatedCodecs, negotiatedDetails.get()); + + if (answer.GetAttributeList().HasAttribute(SdpAttribute::kExtmapAttribute)) { + for (auto& extmapAttr : answer.GetAttributeList().GetExtmap().mExtmaps) { + SdpDirectionAttribute::Direction direction = extmapAttr.direction; + if (&remote == &answer) { + // Answer is remote, we need to flip this. + direction = reverse(direction); + } + + if (direction & mDirection) { + negotiatedDetails->mExtmap[extmapAttr.extensionname] = extmapAttr; + } + } + } + + mInHaveRemote = false; + mNegotiatedDetails = std::move(negotiatedDetails); + return NS_OK; +} + +// When doing bundle, if all else fails we can try to figure out which m-line a +// given RTP packet belongs to by looking at the payload type field. This only +// works, however, if that payload type appeared in only one m-section. +// We figure that out here. +/* static */ +void JsepTrack::SetUniquePayloadTypes(std::vector<JsepTrack*>& tracks) { + // Maps to track details if no other track contains the payload type, + // otherwise maps to nullptr. + std::map<uint16_t, JsepTrackNegotiatedDetails*> payloadTypeToDetailsMap; + + for (JsepTrack* track : tracks) { + if (track->GetMediaType() == SdpMediaSection::kApplication) { + continue; + } + + auto* details = track->GetNegotiatedDetails(); + if (!details) { + // Can happen if negotiation fails on a track + continue; + } + + std::vector<uint16_t> payloadTypesForTrack; + track->GetNegotiatedPayloadTypes(&payloadTypesForTrack); + + for (uint16_t pt : payloadTypesForTrack) { + if (payloadTypeToDetailsMap.count(pt)) { + // Found in more than one track, not unique + payloadTypeToDetailsMap[pt] = nullptr; + } else { + payloadTypeToDetailsMap[pt] = details; + } + } + } + + for (auto ptAndDetails : payloadTypeToDetailsMap) { + uint16_t uniquePt = ptAndDetails.first; + MOZ_ASSERT(uniquePt <= UINT8_MAX); + auto trackDetails = ptAndDetails.second; + + if (trackDetails) { + trackDetails->mUniquePayloadTypes.push_back( + static_cast<uint8_t>(uniquePt)); + } + } +} + +} // namespace mozilla |