Fix race in peer logging

kylecarbs · kylecarbs · commit 7327507ebeb3 · 2022-01-20T14:43:16.000Z
diff --git a/peer/conn.go b/peer/conn.go
@@ -143,9 +143,10 @@ func (c *Conn) init() error {
 		}
 	})
 	c.rtc.OnConnectionStateChange(func(pcs webrtc.PeerConnectionState) {
-		if c.isClosed() {
-			return
-		}
+		// Close must be locked here otherwise log output can appear
+		// after the connection has been closed.
+		c.closeMutex.Lock()
+		defer c.closeMutex.Unlock()
 
 		c.opts.Logger.Debug(context.Background(), "rtc connection updated",
 			slog.F("state", pcs),
