package quic import ( "fmt" "net" "sync" "github.com/lucas-clemente/quic-go/internal/utils" ) var ( connMuxerOnce sync.Once connMuxer multiplexer ) type multiplexer interface { AddConn(net.PacketConn, int) (packetHandlerManager, error) } type connManager struct { connIDLen int manager packetHandlerManager } // The connMultiplexer listens on multiple net.PacketConns and dispatches // incoming packets to the session handler. type connMultiplexer struct { mutex sync.Mutex conns map[net.PacketConn]connManager newPacketHandlerManager func(net.PacketConn, int, utils.Logger) packetHandlerManager // so it can be replaced in the tests logger utils.Logger } var _ multiplexer = &connMultiplexer{} func getMultiplexer() multiplexer { connMuxerOnce.Do(func() { connMuxer = &connMultiplexer{ conns: make(map[net.PacketConn]connManager), logger: utils.DefaultLogger.WithPrefix("muxer"), newPacketHandlerManager: newPacketHandlerMap, } }) return connMuxer } func (m *connMultiplexer) AddConn(c net.PacketConn, connIDLen int) (packetHandlerManager, error) { m.mutex.Lock() defer m.mutex.Unlock() p, ok := m.conns[c] if !ok { manager := m.newPacketHandlerManager(c, connIDLen, m.logger) p = connManager{connIDLen: connIDLen, manager: manager} m.conns[c] = p } if p.connIDLen != connIDLen { return nil, fmt.Errorf("cannot use %d byte connection IDs on a connection that is already using %d byte connction IDs", connIDLen, p.connIDLen) } return p.manager, nil }