Remove redundant lazy allocation

internal/multiplex/session.go

@@ -179,7 +179,7 @@ func (sesh *Session) closeStream(s *Stream, active bool) error {
 	if !atomic.CompareAndSwapUint32(&s.closed, 0, 1) {
 		return fmt.Errorf("closing stream %v: %w", s.id, errRepeatStreamClosing)
 	}
-	_ = s.getRecvBuf().Close() // recvBuf.Close should not return error
+	_ = s.recvBuf.Close() // recvBuf.Close should not return error
 
 	if active {
 		tmpBuf := sesh.streamObfsBufPool.Get().(*[]byte)
@@ -285,7 +285,7 @@ func (sesh *Session) closeSession() error {
 	close(sesh.acceptCh)
 	for id, stream := range sesh.streams {
 		if stream != nil && atomic.CompareAndSwapUint32(&stream.closed, 0, 1) {
-			_ = stream.getRecvBuf().Close() // will not block
+			_ = stream.recvBuf.Close() // will not block
 			delete(sesh.streams, id)
 			sesh.streamCountDecr()
 		}

internal/multiplex/stream.go

@@ -23,9 +23,8 @@ type Stream struct {
 
 	session *Session
 
-	allocIdempot sync.Once
 	// a buffer (implemented as an asynchronous buffered pipe) to put data we've received from recvFrame but hasn't
-	// been read by the consumer through Read or WriteTo. Lazily allocated
+	// been read by the consumer through Read or WriteTo.
 	recvBuf recvBuffer
 
 	writingM     sync.Mutex
@@ -56,25 +55,20 @@ func makeStream(sesh *Session, id uint32) *Stream {
 		},
 	}
 
+	if sesh.Unordered {
+		stream.recvBuf = NewDatagramBufferedPipe()
+	} else {
+		stream.recvBuf = NewStreamBuffer()
+	}
+
 	return stream
 }
 
 func (s *Stream) isClosed() bool { return atomic.LoadUint32(&s.closed) == 1 }
 
-func (s *Stream) getRecvBuf() recvBuffer {
-	s.allocIdempot.Do(func() {
-		if s.session.Unordered {
-			s.recvBuf = NewDatagramBufferedPipe()
-		} else {
-			s.recvBuf = NewStreamBuffer()
-		}
-	})
-	return s.recvBuf
-}
-
 // receive a readily deobfuscated Frame so its payload can later be Read
 func (s *Stream) recvFrame(frame *Frame) error {
-	toBeClosed, err := s.getRecvBuf().Write(frame)
+	toBeClosed, err := s.recvBuf.Write(frame)
 	if toBeClosed {
 		err = s.passiveClose()
 		if errors.Is(err, errRepeatStreamClosing) {
@@ -93,7 +87,7 @@ func (s *Stream) Read(buf []byte) (n int, err error) {
 		return 0, nil
 	}
 
-	n, err = s.getRecvBuf().Read(buf)
+	n, err = s.recvBuf.Read(buf)
 	log.Tracef("%v read from stream %v with err %v", n, s.id, err)
 	if err == io.EOF {
 		return n, ErrBrokenStream
@@ -104,7 +98,7 @@ func (s *Stream) Read(buf []byte) (n int, err error) {
 // WriteTo continuously write data Stream has received into the writer w.
 func (s *Stream) WriteTo(w io.Writer) (int64, error) {
 	// will keep writing until the underlying buffer is closed
-	n, err := s.getRecvBuf().WriteTo(w)
+	n, err := s.recvBuf.WriteTo(w)
 	log.Tracef("%v read from stream %v with err %v", n, s.id, err)
 	if err == io.EOF {
 		return n, ErrBrokenStream
@@ -215,8 +209,8 @@ func (s *Stream) Close() error {
 func (s *Stream) LocalAddr() net.Addr  { return s.session.addrs.Load().([]net.Addr)[0] }
 func (s *Stream) RemoteAddr() net.Addr { return s.session.addrs.Load().([]net.Addr)[1] }
 
-func (s *Stream) SetWriteToTimeout(d time.Duration)  { s.getRecvBuf().SetWriteToTimeout(d) }
-func (s *Stream) SetReadDeadline(t time.Time) error  { s.getRecvBuf().SetReadDeadline(t); return nil }
+func (s *Stream) SetWriteToTimeout(d time.Duration)  { s.recvBuf.SetWriteToTimeout(d) }
+func (s *Stream) SetReadDeadline(t time.Time) error  { s.recvBuf.SetReadDeadline(t); return nil }
 func (s *Stream) SetReadFromTimeout(d time.Duration) { s.readFromTimeout = d }
 
 var errNotImplemented = errors.New("Not implemented")