open ReadBuffer for quic connections

common/buf/reader.go

@@ -24,7 +24,8 @@ func readOneUDP(r io.Reader) (*Buffer, error) {
 	return nil, newError("Reader returns too many empty payloads.")
 }
 
-func readOne(r io.Reader) (*Buffer, error) {
+// ReadBuffer reads a Buffer from the given reader, without allocating large buffer in advance.
+func ReadBuffer(r io.Reader) (*Buffer, error) {
 	// Use an one-byte buffer to wait for incoming payload.
 	var firstByte [1]byte
 	nBytes, err := r.Read(firstByte[:])
@@ -163,7 +164,7 @@ type SingleReader struct {
 
 // ReadMultiBuffer implements Reader.
 func (r *SingleReader) ReadMultiBuffer() (MultiBuffer, error) {
-	b, err := readOne(r.Reader)
+	b, err := ReadBuffer(r.Reader)
 	if err != nil {
 		return nil, err
 	}

common/buf/readv_reader.go

@@ -119,7 +119,7 @@ func (r *ReadVReader) readMulti() (MultiBuffer, error) {
 // ReadMultiBuffer implements Reader.
 func (r *ReadVReader) ReadMultiBuffer() (MultiBuffer, error) {
 	if r.alloc.Current() == 1 {
-		b, err := readOne(r.Reader)
+		b, err := ReadBuffer(r.Reader)
 		if err != nil {
 			return nil, err
 		}

transport/internet/quic/conn.go

@@ -150,17 +150,14 @@ func (c *interConn) Read(b []byte) (int, error) {
 }
 
 func (c *interConn) ReadMultiBuffer() (buf.MultiBuffer, error) {
-	const BufferCount = 16
-	mb := make(buf.MultiBuffer, 0, BufferCount)
-	{
-		b := buf.New()
-		if _, err := b.ReadFrom(c.stream); err != nil {
-			b.Release()
-			return nil, err
-		}
-		mb = append(mb, b)
+	firstBuffer, err := buf.ReadBuffer(c)
+	if err != nil {
+		return nil, err
 	}
 
+	const BufferCount = 16
+	mb := make(buf.MultiBuffer, 0, BufferCount)
+	mb = append(mb, firstBuffer)
 	for len(mb) < BufferCount && c.stream.HasMoreData() {
 		b := buf.New()
 		if _, err := b.ReadFrom(c.stream); err != nil {