Switch back go upstream bwmarrin/discordgo

Commit https://github.com/bwmarrin/discordgo/commit/ffa9956c9b41e8e2a10c26a254389854e016b006 got merged in.

1 files changed, 93 insertions, 77 deletions

diff --git a/vendor/github.com/gorilla/websocket/conn.go b/vendor/github.com/gorilla/websocket/conn.go
index 97e1dbac..d2a21c14 100644
--- a/vendor/github.com/gorilla/websocket/conn.go
+++ b/vendor/github.com/gorilla/websocket/conn.go
@@ -76,7 +76,7 @@ const (
 	// is UTF-8 encoded text.
 	PingMessage = 9
 
-	// PongMessage denotes a ping control message. The optional message payload
+	// PongMessage denotes a pong control message. The optional message payload
 	// is UTF-8 encoded text.
 	PongMessage = 10
 )
@@ -100,9 +100,8 @@ func (e *netError) Error() string   { return e.msg }
 func (e *netError) Temporary() bool { return e.temporary }
 func (e *netError) Timeout() bool   { return e.timeout }
 
-// CloseError represents close frame.
+// CloseError represents a close message.
 type CloseError struct {
-
 	// Code is defined in RFC 6455, section 11.7.
 	Code int
 
@@ -224,6 +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
@@ -233,6 +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
@@ -264,64 +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,
@@ -329,6 +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,
 	}
@@ -343,7 +325,8 @@ func (c *Conn) Subprotocol() string {
 	return c.subprotocol
 }
 
-// Close closes the underlying network connection without sending or waiting for a close frame.
+// Close closes the underlying network connection without sending or waiting
+// for a close message.
 func (c *Conn) Close() error {
 	return c.conn.Close()
 }
@@ -370,7 +353,16 @@ func (c *Conn) writeFatal(err error) error {
 	return err
 }
 
-func (c *Conn) write(frameType int, deadline time.Time, bufs ...[]byte) error {
+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 }()
 
@@ -382,15 +374,14 @@ func (c *Conn) write(frameType int, deadline time.Time, bufs ...[]byte) error {
 	}
 
 	c.conn.SetWriteDeadline(deadline)
-	for _, buf := range bufs {
-		if len(buf) > 0 {
-			_, err := c.conn.Write(buf)
-			if err != nil {
-				return c.writeFatal(err)
-			}
-		}
+	if len(buf1) == 0 {
+		_, err = c.conn.Write(buf0)
+	} else {
+		err = c.writeBufs(buf0, buf1)
+	}
+	if err != nil {
+		return c.writeFatal(err)
 	}
-
 	if frameType == CloseMessage {
 		c.writeFatal(ErrCloseSent)
 	}
@@ -476,7 +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
@@ -484,6 +487,9 @@ func (c *Conn) prepWrite(messageType int) error {
 //
 // There can be at most one open writer on a connection. NextWriter closes the
 // previous writer if the application has not already done so.
+//
+// All message types (TextMessage, BinaryMessage, CloseMessage, PingMessage and
+// PongMessage) are supported.
 func (c *Conn) NextWriter(messageType int) (io.WriteCloser, error) {
 	if err := c.prepWrite(messageType); err != nil {
 		return nil, err
@@ -599,6 +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
 	}
 
@@ -764,7 +774,6 @@ func (c *Conn) SetWriteDeadline(t time.Time) error {
 // Read methods
 
 func (c *Conn) advanceFrame() (int, error) {
-
 	// 1. Skip remainder of previous frame.
 
 	if c.readRemaining > 0 {
@@ -1033,7 +1042,7 @@ func (c *Conn) SetReadDeadline(t time.Time) error {
 }
 
 // SetReadLimit sets the maximum size for a message read from the peer. If a
-// message exceeds the limit, the connection sends a close frame to the peer
+// message exceeds the limit, the connection sends a close message to the peer
 // and returns ErrReadLimit to the application.
 func (c *Conn) SetReadLimit(limit int64) {
 	c.readLimit = limit
@@ -1046,24 +1055,22 @@ func (c *Conn) CloseHandler() func(code int, text string) error {
 
 // SetCloseHandler sets the handler for close messages received from the peer.
 // The code argument to h is the received close code or CloseNoStatusReceived
-// if the close message is empty. The default close handler sends a close frame
-// back to the peer.
+// if the close message is empty. The default close handler sends a close
+// message back to the peer.
 //
-// The application must read the connection to process close messages as
-// described in the section on Control Frames above.
+// The handler function is called from the NextReader, ReadMessage and message
+// reader Read methods. The application must read the connection to process
+// close messages as described in the section on Control Messages above.
 //
-// The connection read methods return a CloseError when a close frame is
+// The connection read methods return a CloseError when a close message is
 // received. Most applications should handle close messages as part of their
 // normal error handling. Applications should only set a close handler when the
-// application must perform some action before sending a close frame back to
+// application must perform some action before sending a close message back to
 // the peer.
 func (c *Conn) SetCloseHandler(h func(code int, text string) error) {
 	if h == nil {
 		h = func(code int, text string) error {
-			message := []byte{}
-			if code != CloseNoStatusReceived {
-				message = FormatCloseMessage(code, "")
-			}
+			message := FormatCloseMessage(code, "")
 			c.WriteControl(CloseMessage, message, time.Now().Add(writeWait))
 			return nil
 		}
@@ -1077,11 +1084,12 @@ func (c *Conn) PingHandler() func(appData string) error {
 }
 
 // SetPingHandler sets the handler for ping messages received from the peer.
-// The appData argument to h is the PING frame application data. The default
+// The appData argument to h is the PING message application data. The default
 // ping handler sends a pong to the peer.
 //
-// The application must read the connection to process ping messages as
-// described in the section on Control Frames above.
+// The handler function is called from the NextReader, ReadMessage and message
+// reader Read methods. The application must read the connection to process
+// ping messages as described in the section on Control Messages above.
 func (c *Conn) SetPingHandler(h func(appData string) error) {
 	if h == nil {
 		h = func(message string) error {
@@ -1103,11 +1111,12 @@ func (c *Conn) PongHandler() func(appData string) error {
 }
 
 // SetPongHandler sets the handler for pong messages received from the peer.
-// The appData argument to h is the PONG frame application data. The default
+// The appData argument to h is the PONG message application data. The default
 // pong handler does nothing.
 //
-// The application must read the connection to process ping messages as
-// described in the section on Control Frames above.
+// The handler function is called from the NextReader, ReadMessage and message
+// reader Read methods. The application must read the connection to process
+// pong messages as described in the section on Control Messages above.
 func (c *Conn) SetPongHandler(h func(appData string) error) {
 	if h == nil {
 		h = func(string) error { return nil }
@@ -1141,7 +1150,14 @@ func (c *Conn) SetCompressionLevel(level int) error {
 }
 
 // FormatCloseMessage formats closeCode and text as a WebSocket close message.
+// An empty message is returned for code CloseNoStatusReceived.
 func FormatCloseMessage(closeCode int, text string) []byte {
+	if closeCode == CloseNoStatusReceived {
+		// Return empty message because it's illegal to send
+		// CloseNoStatusReceived. Return non-nil value in case application
+		// checks for nil.
+		return []byte{}
+	}
 	buf := make([]byte, 2+len(text))
 	binary.BigEndian.PutUint16(buf, uint16(closeCode))
 	copy(buf[2:], text)