1 files changed, 54 insertions, 46 deletions

diff --git a/vendor/github.com/gorilla/websocket/conn.go b/vendor/github.com/gorilla/websocket/conn.go
index 5f46bf4a5..d2a21c148 100644
--- a/vendor/github.com/gorilla/websocket/conn.go
+++ b/vendor/github.com/gorilla/websocket/conn.go
@@ -223,6 +223,20 @@ func isValidReceivedCloseCode(code int) bool {
 	return validReceivedCloseCodes[code] || (code >= 3000 && code <= 4999)
 }
 
+// BufferPool represents a pool of buffers. The *sync.Pool type satisfies this
+// interface.  The type of the value stored in a pool is not specified.
+type BufferPool interface {
+	// Get gets a value from the pool or returns nil if the pool is empty.
+	Get() interface{}
+	// Put adds a value to the pool.
+	Put(interface{})
+}
+
+// writePoolData is the type added to the write buffer pool. This wrapper is
+// used to prevent applications from peeking at and depending on the values
+// added to the pool.
+type writePoolData struct{ buf []byte }
+
 // The Conn type represents a WebSocket connection.
 type Conn struct {
 	conn        net.Conn
@@ -232,6 +246,8 @@ type Conn struct {
 	// Write fields
 	mu            chan bool // used as mutex to protect write to conn
 	writeBuf      []byte    // frame is constructed in this buffer.
+	writePool     BufferPool
+	writeBufSize  int
 	writeDeadline time.Time
 	writer        io.WriteCloser // the current writer returned to the application
 	isWriting     bool           // for best-effort concurrent write detection
@@ -263,64 +279,29 @@ type Conn struct {
 	newDecompressionReader func(io.Reader) io.ReadCloser
 }
 
-func newConn(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int) *Conn {
-	return newConnBRW(conn, isServer, readBufferSize, writeBufferSize, nil)
-}
-
-type writeHook struct {
-	p []byte
-}
-
-func (wh *writeHook) Write(p []byte) (int, error) {
-	wh.p = p
-	return len(p), nil
-}
-
-func newConnBRW(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int, brw *bufio.ReadWriter) *Conn {
-	mu := make(chan bool, 1)
-	mu <- true
+func newConn(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int, writeBufferPool BufferPool, br *bufio.Reader, writeBuf []byte) *Conn {
 
-	var br *bufio.Reader
-	if readBufferSize == 0 && brw != nil && brw.Reader != nil {
-		// Reuse the supplied bufio.Reader if the buffer has a useful size.
-		// This code assumes that peek on a reader returns
-		// bufio.Reader.buf[:0].
-		brw.Reader.Reset(conn)
-		if p, err := brw.Reader.Peek(0); err == nil && cap(p) >= 256 {
-			br = brw.Reader
-		}
-	}
 	if br == nil {
 		if readBufferSize == 0 {
 			readBufferSize = defaultReadBufferSize
-		}
-		if readBufferSize < maxControlFramePayloadSize {
+		} else if readBufferSize < maxControlFramePayloadSize {
+			// must be large enough for control frame
 			readBufferSize = maxControlFramePayloadSize
 		}
 		br = bufio.NewReaderSize(conn, readBufferSize)
 	}
 
-	var writeBuf []byte
-	if writeBufferSize == 0 && brw != nil && brw.Writer != nil {
-		// Use the bufio.Writer's buffer if the buffer has a useful size. This
-		// code assumes that bufio.Writer.buf[:1] is passed to the
-		// bufio.Writer's underlying writer.
-		var wh writeHook
-		brw.Writer.Reset(&wh)
-		brw.Writer.WriteByte(0)
-		brw.Flush()
-		if cap(wh.p) >= maxFrameHeaderSize+256 {
-			writeBuf = wh.p[:cap(wh.p)]
-		}
+	if writeBufferSize <= 0 {
+		writeBufferSize = defaultWriteBufferSize
 	}
+	writeBufferSize += maxFrameHeaderSize
 
-	if writeBuf == nil {
-		if writeBufferSize == 0 {
-			writeBufferSize = defaultWriteBufferSize
-		}
-		writeBuf = make([]byte, writeBufferSize+maxFrameHeaderSize)
+	if writeBuf == nil && writeBufferPool == nil {
+		writeBuf = make([]byte, writeBufferSize)
 	}
 
+	mu := make(chan bool, 1)
+	mu <- true
 	c := &Conn{
 		isServer:               isServer,
 		br:                     br,
@@ -328,6 +309,8 @@ func newConnBRW(conn net.Conn, isServer bool, readBufferSize, writeBufferSize in
 		mu:                     mu,
 		readFinal:              true,
 		writeBuf:               writeBuf,
+		writePool:              writeBufferPool,
+		writeBufSize:           writeBufferSize,
 		enableWriteCompression: true,
 		compressionLevel:       defaultCompressionLevel,
 	}
@@ -370,6 +353,15 @@ func (c *Conn) writeFatal(err error) error {
 	return err
 }
 
+func (c *Conn) read(n int) ([]byte, error) {
+	p, err := c.br.Peek(n)
+	if err == io.EOF {
+		err = errUnexpectedEOF
+	}
+	c.br.Discard(len(p))
+	return p, err
+}
+
 func (c *Conn) write(frameType int, deadline time.Time, buf0, buf1 []byte) error {
 	<-c.mu
 	defer func() { c.mu <- true }()
@@ -475,7 +467,19 @@ func (c *Conn) prepWrite(messageType int) error {
 	c.writeErrMu.Lock()
 	err := c.writeErr
 	c.writeErrMu.Unlock()
-	return err
+	if err != nil {
+		return err
+	}
+
+	if c.writeBuf == nil {
+		wpd, ok := c.writePool.Get().(writePoolData)
+		if ok {
+			c.writeBuf = wpd.buf
+		} else {
+			c.writeBuf = make([]byte, c.writeBufSize)
+		}
+	}
+	return nil
 }
 
 // NextWriter returns a writer for the next message to send. The writer's Close
@@ -601,6 +605,10 @@ func (w *messageWriter) flushFrame(final bool, extra []byte) error {
 
 	if final {
 		c.writer = nil
+		if c.writePool != nil {
+			c.writePool.Put(writePoolData{buf: c.writeBuf})
+			c.writeBuf = nil
+		}
 		return nil
 	}