Исправление Race при renegotiation

sfu/rooms.go

@@ -1,6 +1,7 @@
 package sfu
 
 import (
+	"g365sfu/logger"
 	connection "g365sfu/socket/struct"
 	"sync"
 
@@ -76,43 +77,9 @@ func JoinWithOffer(roomID string, peerID string, offer webrtc.SessionDescription
 		return nil, err
 	}
 
-	peerConnection.OnICECandidate(func(c *webrtc.ICECandidate) {
-		if c == nil {
-			return
-		}
-		if OnLocalICECandidate != nil {
-			OnLocalICECandidate(roomID, peerID, c.ToJSON())
-		}
-	})
-
 	BindPeerLifecycle(roomID, peerID, peerConnection)
 	SetupForwardingForPeer(roomID, peerID, peerConnection)
 
-	room.mu.RLock()
-	existingTracks := make([]RoomTrack, len(room.Tracks))
-	copy(existingTracks, room.Tracks)
-	room.mu.RUnlock()
-
-	for _, t := range existingTracks {
-		if t.OwnerPeer == peerID {
-			continue
-		}
-
-		sender, err := peerConnection.AddTrack(t.Local)
-		if err != nil {
-			continue
-		}
-
-		go func() {
-			buf := make([]byte, 1500)
-			for {
-				if _, _, e := sender.Read(buf); e != nil {
-					return
-				}
-			}
-		}()
-	}
-
 	if err = peerConnection.SetRemoteDescription(offer); err != nil {
 		_ = peerConnection.Close()
 		return nil, err
@@ -131,13 +98,57 @@ func JoinWithOffer(roomID string, peerID string, offer webrtc.SessionDescription
 	}
 	<-gatherDone
 
+	peerConnection.OnICECandidate(func(c *webrtc.ICECandidate) {
+		if c == nil {
+			return
+		}
+		if OnLocalICECandidate != nil {
+			OnLocalICECandidate(roomID, peerID, c.ToJSON())
+		}
+	})
+
+	// Добавляем peer в комнату и сразу снимаем snapshot существующих треков
+	// в одном локе — чтобы не было race с OnTrack
 	room.mu.Lock()
 	room.Peers = append(room.Peers, Peer{
 		PeerID:         peerID,
 		PeerConnection: peerConnection,
 	})
+	existingTracks := make([]RoomTrack, len(room.Tracks))
+	copy(existingTracks, room.Tracks)
 	room.mu.Unlock()
 
+	// Подписываем нового peer на уже существующие треки ПОСЛЕ добавления в комнату
+	for _, t := range existingTracks {
+		if t.OwnerPeer == peerID {
+			continue
+		}
+
+		sender, err := peerConnection.AddTrack(t.Local)
+		if err != nil {
+			continue
+		}
+
+		senderCopy := sender
+		go func() {
+			buf := make([]byte, 1500)
+			for {
+				if _, _, e := senderCopy.Read(buf); e != nil {
+					return
+				}
+			}
+		}()
+	}
+
+	// Если были добавлены треки — нужна renegotiation
+	if len(existingTracks) > 0 {
+		go func() {
+			if err := renegotiatePeer(roomID, peerID, peerConnection); err != nil {
+				logger.LogWarnMessage("JoinWithOffer: renegotiatePeer error: " + err.Error())
+			}
+		}()
+	}
+
 	return peerConnection.LocalDescription(), nil
 }