snapshot of https://github.com/livekit/livekit.git @ 08c5433449c106943231037d0b892895f6e92d3b (2026-09-15)

pkg/rtc/roomtrackmanager.go

@@ -0,0 +1,263 @@
+/*
+ * Copyright 2023 LiveKit, Inc
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package rtc
+
+import (
+	"sync"
+
+	"github.com/livekit/livekit-server/pkg/rtc/types"
+	"github.com/livekit/livekit-server/pkg/utils"
+	"github.com/livekit/protocol/livekit"
+	"github.com/livekit/protocol/logger"
+)
+
+// RoomTrackManager holds tracks that are published to the room
+type RoomTrackManager struct {
+	logger logger.Logger
+
+	lock            sync.RWMutex
+	changedNotifier *utils.ChangeNotifierManager
+	removedNotifier *utils.ChangeNotifierManager
+	tracks          map[livekit.TrackID][]*TrackInfo
+	dataTracks      map[livekit.TrackID][]*DataTrackInfo
+}
+
+type TrackInfo struct {
+	Track             types.MediaTrack
+	PublisherIdentity livekit.ParticipantIdentity
+	PublisherID       livekit.ParticipantID
+}
+
+type DataTrackInfo struct {
+	DataTrack         types.DataTrack
+	PublisherIdentity livekit.ParticipantIdentity
+	PublisherID       livekit.ParticipantID
+}
+
+func NewRoomTrackManager(logger logger.Logger) *RoomTrackManager {
+	return &RoomTrackManager{
+		logger:          logger,
+		tracks:          make(map[livekit.TrackID][]*TrackInfo),
+		dataTracks:      make(map[livekit.TrackID][]*DataTrackInfo),
+		changedNotifier: utils.NewChangeNotifierManager(),
+		removedNotifier: utils.NewChangeNotifierManager(),
+	}
+}
+
+func (r *RoomTrackManager) AddTrack(track types.MediaTrack, publisherIdentity livekit.ParticipantIdentity, publisherID livekit.ParticipantID) {
+	trackID := track.ID()
+	r.lock.Lock()
+	infos, ok := r.tracks[trackID]
+	if ok {
+		for _, info := range infos {
+			if info.Track == track {
+				r.lock.Unlock()
+				r.logger.Infow("not adding duplicate track", "trackID", trackID)
+				return
+			}
+		}
+	}
+	r.tracks[trackID] = append(r.tracks[trackID], &TrackInfo{
+		Track:             track,
+		PublisherIdentity: publisherIdentity,
+		PublisherID:       publisherID,
+	})
+	r.lock.Unlock()
+
+	r.NotifyTrackChanged(trackID)
+}
+
+func (r *RoomTrackManager) RemoveTrack(track types.MediaTrack) {
+	trackID := track.ID()
+	r.lock.Lock()
+	// ensure we are removing the same track as added
+	infos, ok := r.tracks[trackID]
+	if !ok {
+		r.lock.Unlock()
+		return
+	}
+
+	numRemoved := 0
+	idx := 0
+	for _, info := range infos {
+		if info.Track == track {
+			numRemoved++
+		} else {
+			r.tracks[trackID][idx] = info
+			idx++
+		}
+	}
+	for j := idx; j < len(infos); j++ {
+		r.tracks[trackID][j] = nil
+	}
+	r.tracks[trackID] = r.tracks[trackID][:idx]
+	if len(r.tracks[trackID]) == 0 {
+		delete(r.tracks, trackID)
+	}
+	r.lock.Unlock()
+	if numRemoved == 0 {
+		return
+	}
+	if numRemoved > 1 {
+		r.logger.Warnw("removed multiple tracks", nil, "trackID", trackID, "numRemoved", numRemoved)
+	}
+
+	n := r.removedNotifier.GetNotifier(string(trackID))
+	if n != nil {
+		n.NotifyChanged()
+	}
+
+	r.changedNotifier.RemoveNotifier(string(trackID), true)
+	r.removedNotifier.RemoveNotifier(string(trackID), true)
+}
+
+func (r *RoomTrackManager) GetTrackInfo(trackID livekit.TrackID) *TrackInfo {
+	r.lock.RLock()
+	defer r.lock.RUnlock()
+
+	infos := r.tracks[trackID]
+	if len(infos) == 0 {
+		return nil
+	}
+
+	// earliest added track is used till it is removed
+	info := infos[0]
+
+	// when track is about to close, do not resolve
+	if info.Track != nil && !info.Track.IsOpen() {
+		return nil
+	}
+	return info
+}
+
+func (r *RoomTrackManager) NotifyTrackChanged(trackID livekit.TrackID) {
+	n := r.changedNotifier.GetNotifier(string(trackID))
+	if n != nil {
+		n.NotifyChanged()
+	}
+}
+
+// HasObservers lets caller know if the current media track has any observers
+// this is used to signal interest in the track. when another MediaTrack with the same
+// trackID is being used, track is not considered to be observed.
+func (r *RoomTrackManager) HasObservers(track types.MediaTrack) bool {
+	n := r.changedNotifier.GetNotifier(string(track.ID()))
+	if n == nil || !n.HasObservers() {
+		return false
+	}
+
+	info := r.GetTrackInfo(track.ID())
+	if info == nil || info.Track != track {
+		return false
+	}
+	return true
+}
+
+func (r *RoomTrackManager) GetOrCreateTrackChangeNotifier(trackID livekit.TrackID) *utils.ChangeNotifier {
+	return r.changedNotifier.GetOrCreateNotifier(string(trackID))
+}
+
+func (r *RoomTrackManager) GetOrCreateTrackRemoveNotifier(trackID livekit.TrackID) *utils.ChangeNotifier {
+	return r.removedNotifier.GetOrCreateNotifier(string(trackID))
+}
+
+func (r *RoomTrackManager) AddDataTrack(dataTrack types.DataTrack, publisherIdentity livekit.ParticipantIdentity, publisherID livekit.ParticipantID) {
+	trackID := dataTrack.ID()
+	r.lock.Lock()
+	infos, ok := r.dataTracks[trackID]
+	if ok {
+		for _, info := range infos {
+			if info.DataTrack == dataTrack {
+				r.lock.Unlock()
+				r.logger.Infow("not adding duplicate data track", "trackID", trackID)
+				return
+			}
+		}
+	}
+	r.dataTracks[trackID] = append(r.dataTracks[trackID], &DataTrackInfo{
+		DataTrack:         dataTrack,
+		PublisherIdentity: publisherIdentity,
+		PublisherID:       publisherID,
+	})
+	r.lock.Unlock()
+
+	r.NotifyTrackChanged(trackID)
+}
+
+func (r *RoomTrackManager) RemoveDataTrack(dataTrack types.DataTrack) {
+	trackID := dataTrack.ID()
+	r.lock.Lock()
+	// ensure we are removing the same track as added
+	infos, ok := r.dataTracks[trackID]
+	if !ok {
+		r.lock.Unlock()
+		return
+	}
+
+	numRemoved := 0
+	idx := 0
+	for _, info := range infos {
+		if info.DataTrack == dataTrack {
+			numRemoved++
+		} else {
+			r.dataTracks[trackID][idx] = info
+			idx++
+		}
+	}
+	for j := idx; j < len(infos); j++ {
+		r.dataTracks[trackID][j] = nil
+	}
+	r.dataTracks[trackID] = r.dataTracks[trackID][:idx]
+	if len(r.dataTracks[trackID]) == 0 {
+		delete(r.dataTracks, trackID)
+	}
+	r.lock.Unlock()
+	if numRemoved == 0 {
+		return
+	}
+	if numRemoved > 1 {
+		r.logger.Warnw("removed multiple data tracks", nil, "trackID", trackID, "numRemoved", numRemoved)
+	}
+
+	n := r.removedNotifier.GetNotifier(string(trackID))
+	if n != nil {
+		n.NotifyChanged()
+	}
+
+	r.changedNotifier.RemoveNotifier(string(trackID), true)
+	r.removedNotifier.RemoveNotifier(string(trackID), true)
+}
+
+func (r *RoomTrackManager) GetDataTrackInfo(trackID livekit.TrackID) *DataTrackInfo {
+	r.lock.RLock()
+	defer r.lock.RUnlock()
+
+	infos := r.dataTracks[trackID]
+	if len(infos) == 0 {
+		return nil
+	}
+
+	// earliest added data track is used till it is removed
+	return infos[0]
+}
+
+func (r *RoomTrackManager) Report() (int, int) {
+	r.lock.RLock()
+	defer r.lock.RUnlock()
+
+	return len(r.tracks), len(r.dataTracks)
+}