From 2f0b35e3c25bc4394f3288e1baa77d250cb510ed Mon Sep 17 00:00:00 2001 From: Jordan Date: Thu, 10 Feb 2022 19:10:54 -0700 Subject: misc: go mod vendor --- vendor/github.com/gorilla/websocket/conn.go | 1165 +++++++++++++++++++++++++++ 1 file changed, 1165 insertions(+) create mode 100644 vendor/github.com/gorilla/websocket/conn.go (limited to 'vendor/github.com/gorilla/websocket/conn.go') diff --git a/vendor/github.com/gorilla/websocket/conn.go b/vendor/github.com/gorilla/websocket/conn.go new file mode 100644 index 0000000..d2a21c1 --- /dev/null +++ b/vendor/github.com/gorilla/websocket/conn.go @@ -0,0 +1,1165 @@ +// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package websocket + +import ( + "bufio" + "encoding/binary" + "errors" + "io" + "io/ioutil" + "math/rand" + "net" + "strconv" + "sync" + "time" + "unicode/utf8" +) + +const ( + // Frame header byte 0 bits from Section 5.2 of RFC 6455 + finalBit = 1 << 7 + rsv1Bit = 1 << 6 + rsv2Bit = 1 << 5 + rsv3Bit = 1 << 4 + + // Frame header byte 1 bits from Section 5.2 of RFC 6455 + maskBit = 1 << 7 + + maxFrameHeaderSize = 2 + 8 + 4 // Fixed header + length + mask + maxControlFramePayloadSize = 125 + + writeWait = time.Second + + defaultReadBufferSize = 4096 + defaultWriteBufferSize = 4096 + + continuationFrame = 0 + noFrame = -1 +) + +// Close codes defined in RFC 6455, section 11.7. +const ( + CloseNormalClosure = 1000 + CloseGoingAway = 1001 + CloseProtocolError = 1002 + CloseUnsupportedData = 1003 + CloseNoStatusReceived = 1005 + CloseAbnormalClosure = 1006 + CloseInvalidFramePayloadData = 1007 + ClosePolicyViolation = 1008 + CloseMessageTooBig = 1009 + CloseMandatoryExtension = 1010 + CloseInternalServerErr = 1011 + CloseServiceRestart = 1012 + CloseTryAgainLater = 1013 + CloseTLSHandshake = 1015 +) + +// The message types are defined in RFC 6455, section 11.8. +const ( + // TextMessage denotes a text data message. The text message payload is + // interpreted as UTF-8 encoded text data. + TextMessage = 1 + + // BinaryMessage denotes a binary data message. + BinaryMessage = 2 + + // CloseMessage denotes a close control message. The optional message + // payload contains a numeric code and text. Use the FormatCloseMessage + // function to format a close message payload. + CloseMessage = 8 + + // PingMessage denotes a ping control message. The optional message payload + // is UTF-8 encoded text. + PingMessage = 9 + + // PongMessage denotes a pong control message. The optional message payload + // is UTF-8 encoded text. + PongMessage = 10 +) + +// ErrCloseSent is returned when the application writes a message to the +// connection after sending a close message. +var ErrCloseSent = errors.New("websocket: close sent") + +// ErrReadLimit is returned when reading a message that is larger than the +// read limit set for the connection. +var ErrReadLimit = errors.New("websocket: read limit exceeded") + +// netError satisfies the net Error interface. +type netError struct { + msg string + temporary bool + timeout bool +} + +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 a close message. +type CloseError struct { + // Code is defined in RFC 6455, section 11.7. + Code int + + // Text is the optional text payload. + Text string +} + +func (e *CloseError) Error() string { + s := []byte("websocket: close ") + s = strconv.AppendInt(s, int64(e.Code), 10) + switch e.Code { + case CloseNormalClosure: + s = append(s, " (normal)"...) + case CloseGoingAway: + s = append(s, " (going away)"...) + case CloseProtocolError: + s = append(s, " (protocol error)"...) + case CloseUnsupportedData: + s = append(s, " (unsupported data)"...) + case CloseNoStatusReceived: + s = append(s, " (no status)"...) + case CloseAbnormalClosure: + s = append(s, " (abnormal closure)"...) + case CloseInvalidFramePayloadData: + s = append(s, " (invalid payload data)"...) + case ClosePolicyViolation: + s = append(s, " (policy violation)"...) + case CloseMessageTooBig: + s = append(s, " (message too big)"...) + case CloseMandatoryExtension: + s = append(s, " (mandatory extension missing)"...) + case CloseInternalServerErr: + s = append(s, " (internal server error)"...) + case CloseTLSHandshake: + s = append(s, " (TLS handshake error)"...) + } + if e.Text != "" { + s = append(s, ": "...) + s = append(s, e.Text...) + } + return string(s) +} + +// IsCloseError returns boolean indicating whether the error is a *CloseError +// with one of the specified codes. +func IsCloseError(err error, codes ...int) bool { + if e, ok := err.(*CloseError); ok { + for _, code := range codes { + if e.Code == code { + return true + } + } + } + return false +} + +// IsUnexpectedCloseError returns boolean indicating whether the error is a +// *CloseError with a code not in the list of expected codes. +func IsUnexpectedCloseError(err error, expectedCodes ...int) bool { + if e, ok := err.(*CloseError); ok { + for _, code := range expectedCodes { + if e.Code == code { + return false + } + } + return true + } + return false +} + +var ( + errWriteTimeout = &netError{msg: "websocket: write timeout", timeout: true, temporary: true} + errUnexpectedEOF = &CloseError{Code: CloseAbnormalClosure, Text: io.ErrUnexpectedEOF.Error()} + errBadWriteOpCode = errors.New("websocket: bad write message type") + errWriteClosed = errors.New("websocket: write closed") + errInvalidControlFrame = errors.New("websocket: invalid control frame") +) + +func newMaskKey() [4]byte { + n := rand.Uint32() + return [4]byte{byte(n), byte(n >> 8), byte(n >> 16), byte(n >> 24)} +} + +func hideTempErr(err error) error { + if e, ok := err.(net.Error); ok && e.Temporary() { + err = &netError{msg: e.Error(), timeout: e.Timeout()} + } + return err +} + +func isControl(frameType int) bool { + return frameType == CloseMessage || frameType == PingMessage || frameType == PongMessage +} + +func isData(frameType int) bool { + return frameType == TextMessage || frameType == BinaryMessage +} + +var validReceivedCloseCodes = map[int]bool{ + // see http://www.iana.org/assignments/websocket/websocket.xhtml#close-code-number + + CloseNormalClosure: true, + CloseGoingAway: true, + CloseProtocolError: true, + CloseUnsupportedData: true, + CloseNoStatusReceived: false, + CloseAbnormalClosure: false, + CloseInvalidFramePayloadData: true, + ClosePolicyViolation: true, + CloseMessageTooBig: true, + CloseMandatoryExtension: true, + CloseInternalServerErr: true, + CloseServiceRestart: true, + CloseTryAgainLater: true, + CloseTLSHandshake: false, +} + +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 + isServer bool + subprotocol string + + // 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 + + writeErrMu sync.Mutex + writeErr error + + enableWriteCompression bool + compressionLevel int + newCompressionWriter func(io.WriteCloser, int) io.WriteCloser + + // Read fields + reader io.ReadCloser // the current reader returned to the application + readErr error + br *bufio.Reader + readRemaining int64 // bytes remaining in current frame. + readFinal bool // true the current message has more frames. + readLength int64 // Message size. + readLimit int64 // Maximum message size. + readMaskPos int + readMaskKey [4]byte + handlePong func(string) error + handlePing func(string) error + handleClose func(int, string) error + readErrCount int + messageReader *messageReader // the current low-level reader + + readDecompress bool // whether last read frame had RSV1 set + newDecompressionReader func(io.Reader) io.ReadCloser +} + +func newConn(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int, writeBufferPool BufferPool, br *bufio.Reader, writeBuf []byte) *Conn { + + if br == nil { + if readBufferSize == 0 { + readBufferSize = defaultReadBufferSize + } else if readBufferSize < maxControlFramePayloadSize { + // must be large enough for control frame + readBufferSize = maxControlFramePayloadSize + } + br = bufio.NewReaderSize(conn, readBufferSize) + } + + if writeBufferSize <= 0 { + writeBufferSize = defaultWriteBufferSize + } + writeBufferSize += maxFrameHeaderSize + + if writeBuf == nil && writeBufferPool == nil { + writeBuf = make([]byte, writeBufferSize) + } + + mu := make(chan bool, 1) + mu <- true + c := &Conn{ + isServer: isServer, + br: br, + conn: conn, + mu: mu, + readFinal: true, + writeBuf: writeBuf, + writePool: writeBufferPool, + writeBufSize: writeBufferSize, + enableWriteCompression: true, + compressionLevel: defaultCompressionLevel, + } + c.SetCloseHandler(nil) + c.SetPingHandler(nil) + c.SetPongHandler(nil) + return c +} + +// Subprotocol returns the negotiated protocol for the connection. +func (c *Conn) Subprotocol() string { + return c.subprotocol +} + +// Close closes the underlying network connection without sending or waiting +// for a close message. +func (c *Conn) Close() error { + return c.conn.Close() +} + +// LocalAddr returns the local network address. +func (c *Conn) LocalAddr() net.Addr { + return c.conn.LocalAddr() +} + +// RemoteAddr returns the remote network address. +func (c *Conn) RemoteAddr() net.Addr { + return c.conn.RemoteAddr() +} + +// Write methods + +func (c *Conn) writeFatal(err error) error { + err = hideTempErr(err) + c.writeErrMu.Lock() + if c.writeErr == nil { + c.writeErr = err + } + c.writeErrMu.Unlock() + 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 }() + + c.writeErrMu.Lock() + err := c.writeErr + c.writeErrMu.Unlock() + if err != nil { + return err + } + + c.conn.SetWriteDeadline(deadline) + 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) + } + return nil +} + +// WriteControl writes a control message with the given deadline. The allowed +// message types are CloseMessage, PingMessage and PongMessage. +func (c *Conn) WriteControl(messageType int, data []byte, deadline time.Time) error { + if !isControl(messageType) { + return errBadWriteOpCode + } + if len(data) > maxControlFramePayloadSize { + return errInvalidControlFrame + } + + b0 := byte(messageType) | finalBit + b1 := byte(len(data)) + if !c.isServer { + b1 |= maskBit + } + + buf := make([]byte, 0, maxFrameHeaderSize+maxControlFramePayloadSize) + buf = append(buf, b0, b1) + + if c.isServer { + buf = append(buf, data...) + } else { + key := newMaskKey() + buf = append(buf, key[:]...) + buf = append(buf, data...) + maskBytes(key, 0, buf[6:]) + } + + d := time.Hour * 1000 + if !deadline.IsZero() { + d = deadline.Sub(time.Now()) + if d < 0 { + return errWriteTimeout + } + } + + timer := time.NewTimer(d) + select { + case <-c.mu: + timer.Stop() + case <-timer.C: + return errWriteTimeout + } + defer func() { c.mu <- true }() + + c.writeErrMu.Lock() + err := c.writeErr + c.writeErrMu.Unlock() + if err != nil { + return err + } + + c.conn.SetWriteDeadline(deadline) + _, err = c.conn.Write(buf) + if err != nil { + return c.writeFatal(err) + } + if messageType == CloseMessage { + c.writeFatal(ErrCloseSent) + } + return err +} + +func (c *Conn) prepWrite(messageType int) error { + // Close previous writer if not already closed by the application. It's + // probably better to return an error in this situation, but we cannot + // change this without breaking existing applications. + if c.writer != nil { + c.writer.Close() + c.writer = nil + } + + if !isControl(messageType) && !isData(messageType) { + return errBadWriteOpCode + } + + c.writeErrMu.Lock() + err := c.writeErr + c.writeErrMu.Unlock() + 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 +// method flushes the complete message to the network. +// +// 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 + } + + mw := &messageWriter{ + c: c, + frameType: messageType, + pos: maxFrameHeaderSize, + } + c.writer = mw + if c.newCompressionWriter != nil && c.enableWriteCompression && isData(messageType) { + w := c.newCompressionWriter(c.writer, c.compressionLevel) + mw.compress = true + c.writer = w + } + return c.writer, nil +} + +type messageWriter struct { + c *Conn + compress bool // whether next call to flushFrame should set RSV1 + pos int // end of data in writeBuf. + frameType int // type of the current frame. + err error +} + +func (w *messageWriter) fatal(err error) error { + if w.err != nil { + w.err = err + w.c.writer = nil + } + return err +} + +// flushFrame writes buffered data and extra as a frame to the network. The +// final argument indicates that this is the last frame in the message. +func (w *messageWriter) flushFrame(final bool, extra []byte) error { + c := w.c + length := w.pos - maxFrameHeaderSize + len(extra) + + // Check for invalid control frames. + if isControl(w.frameType) && + (!final || length > maxControlFramePayloadSize) { + return w.fatal(errInvalidControlFrame) + } + + b0 := byte(w.frameType) + if final { + b0 |= finalBit + } + if w.compress { + b0 |= rsv1Bit + } + w.compress = false + + b1 := byte(0) + if !c.isServer { + b1 |= maskBit + } + + // Assume that the frame starts at beginning of c.writeBuf. + framePos := 0 + if c.isServer { + // Adjust up if mask not included in the header. + framePos = 4 + } + + switch { + case length >= 65536: + c.writeBuf[framePos] = b0 + c.writeBuf[framePos+1] = b1 | 127 + binary.BigEndian.PutUint64(c.writeBuf[framePos+2:], uint64(length)) + case length > 125: + framePos += 6 + c.writeBuf[framePos] = b0 + c.writeBuf[framePos+1] = b1 | 126 + binary.BigEndian.PutUint16(c.writeBuf[framePos+2:], uint16(length)) + default: + framePos += 8 + c.writeBuf[framePos] = b0 + c.writeBuf[framePos+1] = b1 | byte(length) + } + + if !c.isServer { + key := newMaskKey() + copy(c.writeBuf[maxFrameHeaderSize-4:], key[:]) + maskBytes(key, 0, c.writeBuf[maxFrameHeaderSize:w.pos]) + if len(extra) > 0 { + return c.writeFatal(errors.New("websocket: internal error, extra used in client mode")) + } + } + + // Write the buffers to the connection with best-effort detection of + // concurrent writes. See the concurrency section in the package + // documentation for more info. + + if c.isWriting { + panic("concurrent write to websocket connection") + } + c.isWriting = true + + err := c.write(w.frameType, c.writeDeadline, c.writeBuf[framePos:w.pos], extra) + + if !c.isWriting { + panic("concurrent write to websocket connection") + } + c.isWriting = false + + if err != nil { + return w.fatal(err) + } + + if final { + c.writer = nil + if c.writePool != nil { + c.writePool.Put(writePoolData{buf: c.writeBuf}) + c.writeBuf = nil + } + return nil + } + + // Setup for next frame. + w.pos = maxFrameHeaderSize + w.frameType = continuationFrame + return nil +} + +func (w *messageWriter) ncopy(max int) (int, error) { + n := len(w.c.writeBuf) - w.pos + if n <= 0 { + if err := w.flushFrame(false, nil); err != nil { + return 0, err + } + n = len(w.c.writeBuf) - w.pos + } + if n > max { + n = max + } + return n, nil +} + +func (w *messageWriter) Write(p []byte) (int, error) { + if w.err != nil { + return 0, w.err + } + + if len(p) > 2*len(w.c.writeBuf) && w.c.isServer { + // Don't buffer large messages. + err := w.flushFrame(false, p) + if err != nil { + return 0, err + } + return len(p), nil + } + + nn := len(p) + for len(p) > 0 { + n, err := w.ncopy(len(p)) + if err != nil { + return 0, err + } + copy(w.c.writeBuf[w.pos:], p[:n]) + w.pos += n + p = p[n:] + } + return nn, nil +} + +func (w *messageWriter) WriteString(p string) (int, error) { + if w.err != nil { + return 0, w.err + } + + nn := len(p) + for len(p) > 0 { + n, err := w.ncopy(len(p)) + if err != nil { + return 0, err + } + copy(w.c.writeBuf[w.pos:], p[:n]) + w.pos += n + p = p[n:] + } + return nn, nil +} + +func (w *messageWriter) ReadFrom(r io.Reader) (nn int64, err error) { + if w.err != nil { + return 0, w.err + } + for { + if w.pos == len(w.c.writeBuf) { + err = w.flushFrame(false, nil) + if err != nil { + break + } + } + var n int + n, err = r.Read(w.c.writeBuf[w.pos:]) + w.pos += n + nn += int64(n) + if err != nil { + if err == io.EOF { + err = nil + } + break + } + } + return nn, err +} + +func (w *messageWriter) Close() error { + if w.err != nil { + return w.err + } + if err := w.flushFrame(true, nil); err != nil { + return err + } + w.err = errWriteClosed + return nil +} + +// WritePreparedMessage writes prepared message into connection. +func (c *Conn) WritePreparedMessage(pm *PreparedMessage) error { + frameType, frameData, err := pm.frame(prepareKey{ + isServer: c.isServer, + compress: c.newCompressionWriter != nil && c.enableWriteCompression && isData(pm.messageType), + compressionLevel: c.compressionLevel, + }) + if err != nil { + return err + } + if c.isWriting { + panic("concurrent write to websocket connection") + } + c.isWriting = true + err = c.write(frameType, c.writeDeadline, frameData, nil) + if !c.isWriting { + panic("concurrent write to websocket connection") + } + c.isWriting = false + return err +} + +// WriteMessage is a helper method for getting a writer using NextWriter, +// writing the message and closing the writer. +func (c *Conn) WriteMessage(messageType int, data []byte) error { + + if c.isServer && (c.newCompressionWriter == nil || !c.enableWriteCompression) { + // Fast path with no allocations and single frame. + + if err := c.prepWrite(messageType); err != nil { + return err + } + mw := messageWriter{c: c, frameType: messageType, pos: maxFrameHeaderSize} + n := copy(c.writeBuf[mw.pos:], data) + mw.pos += n + data = data[n:] + return mw.flushFrame(true, data) + } + + w, err := c.NextWriter(messageType) + if err != nil { + return err + } + if _, err = w.Write(data); err != nil { + return err + } + return w.Close() +} + +// SetWriteDeadline sets the write deadline on the underlying network +// connection. After a write has timed out, the websocket state is corrupt and +// all future writes will return an error. A zero value for t means writes will +// not time out. +func (c *Conn) SetWriteDeadline(t time.Time) error { + c.writeDeadline = t + return nil +} + +// Read methods + +func (c *Conn) advanceFrame() (int, error) { + // 1. Skip remainder of previous frame. + + if c.readRemaining > 0 { + if _, err := io.CopyN(ioutil.Discard, c.br, c.readRemaining); err != nil { + return noFrame, err + } + } + + // 2. Read and parse first two bytes of frame header. + + p, err := c.read(2) + if err != nil { + return noFrame, err + } + + final := p[0]&finalBit != 0 + frameType := int(p[0] & 0xf) + mask := p[1]&maskBit != 0 + c.readRemaining = int64(p[1] & 0x7f) + + c.readDecompress = false + if c.newDecompressionReader != nil && (p[0]&rsv1Bit) != 0 { + c.readDecompress = true + p[0] &^= rsv1Bit + } + + if rsv := p[0] & (rsv1Bit | rsv2Bit | rsv3Bit); rsv != 0 { + return noFrame, c.handleProtocolError("unexpected reserved bits 0x" + strconv.FormatInt(int64(rsv), 16)) + } + + switch frameType { + case CloseMessage, PingMessage, PongMessage: + if c.readRemaining > maxControlFramePayloadSize { + return noFrame, c.handleProtocolError("control frame length > 125") + } + if !final { + return noFrame, c.handleProtocolError("control frame not final") + } + case TextMessage, BinaryMessage: + if !c.readFinal { + return noFrame, c.handleProtocolError("message start before final message frame") + } + c.readFinal = final + case continuationFrame: + if c.readFinal { + return noFrame, c.handleProtocolError("continuation after final message frame") + } + c.readFinal = final + default: + return noFrame, c.handleProtocolError("unknown opcode " + strconv.Itoa(frameType)) + } + + // 3. Read and parse frame length. + + switch c.readRemaining { + case 126: + p, err := c.read(2) + if err != nil { + return noFrame, err + } + c.readRemaining = int64(binary.BigEndian.Uint16(p)) + case 127: + p, err := c.read(8) + if err != nil { + return noFrame, err + } + c.readRemaining = int64(binary.BigEndian.Uint64(p)) + } + + // 4. Handle frame masking. + + if mask != c.isServer { + return noFrame, c.handleProtocolError("incorrect mask flag") + } + + if mask { + c.readMaskPos = 0 + p, err := c.read(len(c.readMaskKey)) + if err != nil { + return noFrame, err + } + copy(c.readMaskKey[:], p) + } + + // 5. For text and binary messages, enforce read limit and return. + + if frameType == continuationFrame || frameType == TextMessage || frameType == BinaryMessage { + + c.readLength += c.readRemaining + if c.readLimit > 0 && c.readLength > c.readLimit { + c.WriteControl(CloseMessage, FormatCloseMessage(CloseMessageTooBig, ""), time.Now().Add(writeWait)) + return noFrame, ErrReadLimit + } + + return frameType, nil + } + + // 6. Read control frame payload. + + var payload []byte + if c.readRemaining > 0 { + payload, err = c.read(int(c.readRemaining)) + c.readRemaining = 0 + if err != nil { + return noFrame, err + } + if c.isServer { + maskBytes(c.readMaskKey, 0, payload) + } + } + + // 7. Process control frame payload. + + switch frameType { + case PongMessage: + if err := c.handlePong(string(payload)); err != nil { + return noFrame, err + } + case PingMessage: + if err := c.handlePing(string(payload)); err != nil { + return noFrame, err + } + case CloseMessage: + closeCode := CloseNoStatusReceived + closeText := "" + if len(payload) >= 2 { + closeCode = int(binary.BigEndian.Uint16(payload)) + if !isValidReceivedCloseCode(closeCode) { + return noFrame, c.handleProtocolError("invalid close code") + } + closeText = string(payload[2:]) + if !utf8.ValidString(closeText) { + return noFrame, c.handleProtocolError("invalid utf8 payload in close frame") + } + } + if err := c.handleClose(closeCode, closeText); err != nil { + return noFrame, err + } + return noFrame, &CloseError{Code: closeCode, Text: closeText} + } + + return frameType, nil +} + +func (c *Conn) handleProtocolError(message string) error { + c.WriteControl(CloseMessage, FormatCloseMessage(CloseProtocolError, message), time.Now().Add(writeWait)) + return errors.New("websocket: " + message) +} + +// NextReader returns the next data message received from the peer. The +// returned messageType is either TextMessage or BinaryMessage. +// +// There can be at most one open reader on a connection. NextReader discards +// the previous message if the application has not already consumed it. +// +// Applications must break out of the application's read loop when this method +// returns a non-nil error value. Errors returned from this method are +// permanent. Once this method returns a non-nil error, all subsequent calls to +// this method return the same error. +func (c *Conn) NextReader() (messageType int, r io.Reader, err error) { + // Close previous reader, only relevant for decompression. + if c.reader != nil { + c.reader.Close() + c.reader = nil + } + + c.messageReader = nil + c.readLength = 0 + + for c.readErr == nil { + frameType, err := c.advanceFrame() + if err != nil { + c.readErr = hideTempErr(err) + break + } + if frameType == TextMessage || frameType == BinaryMessage { + c.messageReader = &messageReader{c} + c.reader = c.messageReader + if c.readDecompress { + c.reader = c.newDecompressionReader(c.reader) + } + return frameType, c.reader, nil + } + } + + // Applications that do handle the error returned from this method spin in + // tight loop on connection failure. To help application developers detect + // this error, panic on repeated reads to the failed connection. + c.readErrCount++ + if c.readErrCount >= 1000 { + panic("repeated read on failed websocket connection") + } + + return noFrame, nil, c.readErr +} + +type messageReader struct{ c *Conn } + +func (r *messageReader) Read(b []byte) (int, error) { + c := r.c + if c.messageReader != r { + return 0, io.EOF + } + + for c.readErr == nil { + + if c.readRemaining > 0 { + if int64(len(b)) > c.readRemaining { + b = b[:c.readRemaining] + } + n, err := c.br.Read(b) + c.readErr = hideTempErr(err) + if c.isServer { + c.readMaskPos = maskBytes(c.readMaskKey, c.readMaskPos, b[:n]) + } + c.readRemaining -= int64(n) + if c.readRemaining > 0 && c.readErr == io.EOF { + c.readErr = errUnexpectedEOF + } + return n, c.readErr + } + + if c.readFinal { + c.messageReader = nil + return 0, io.EOF + } + + frameType, err := c.advanceFrame() + switch { + case err != nil: + c.readErr = hideTempErr(err) + case frameType == TextMessage || frameType == BinaryMessage: + c.readErr = errors.New("websocket: internal error, unexpected text or binary in Reader") + } + } + + err := c.readErr + if err == io.EOF && c.messageReader == r { + err = errUnexpectedEOF + } + return 0, err +} + +func (r *messageReader) Close() error { + return nil +} + +// ReadMessage is a helper method for getting a reader using NextReader and +// reading from that reader to a buffer. +func (c *Conn) ReadMessage() (messageType int, p []byte, err error) { + var r io.Reader + messageType, r, err = c.NextReader() + if err != nil { + return messageType, nil, err + } + p, err = ioutil.ReadAll(r) + return messageType, p, err +} + +// SetReadDeadline sets the read deadline on the underlying network connection. +// After a read has timed out, the websocket connection state is corrupt and +// all future reads will return an error. A zero value for t means reads will +// not time out. +func (c *Conn) SetReadDeadline(t time.Time) error { + return c.conn.SetReadDeadline(t) +} + +// SetReadLimit sets the maximum size for a message read from the peer. If a +// 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 +} + +// CloseHandler returns the current close handler +func (c *Conn) CloseHandler() func(code int, text string) error { + return c.handleClose +} + +// 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 +// message back to the peer. +// +// 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 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 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 := FormatCloseMessage(code, "") + c.WriteControl(CloseMessage, message, time.Now().Add(writeWait)) + return nil + } + } + c.handleClose = h +} + +// PingHandler returns the current ping handler +func (c *Conn) PingHandler() func(appData string) error { + return c.handlePing +} + +// SetPingHandler sets the handler for ping messages received from the peer. +// The appData argument to h is the PING message application data. The default +// ping handler sends a pong to the peer. +// +// 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 { + err := c.WriteControl(PongMessage, []byte(message), time.Now().Add(writeWait)) + if err == ErrCloseSent { + return nil + } else if e, ok := err.(net.Error); ok && e.Temporary() { + return nil + } + return err + } + } + c.handlePing = h +} + +// PongHandler returns the current pong handler +func (c *Conn) PongHandler() func(appData string) error { + return c.handlePong +} + +// SetPongHandler sets the handler for pong messages received from the peer. +// The appData argument to h is the PONG message application data. The default +// pong handler does nothing. +// +// 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 } + } + c.handlePong = h +} + +// UnderlyingConn returns the internal net.Conn. This can be used to further +// modifications to connection specific flags. +func (c *Conn) UnderlyingConn() net.Conn { + return c.conn +} + +// EnableWriteCompression enables and disables write compression of +// subsequent text and binary messages. This function is a noop if +// compression was not negotiated with the peer. +func (c *Conn) EnableWriteCompression(enable bool) { + c.enableWriteCompression = enable +} + +// SetCompressionLevel sets the flate compression level for subsequent text and +// binary messages. This function is a noop if compression was not negotiated +// with the peer. See the compress/flate package for a description of +// compression levels. +func (c *Conn) SetCompressionLevel(level int) error { + if !isValidCompressionLevel(level) { + return errors.New("websocket: invalid compression level") + } + c.compressionLevel = level + return nil +} + +// 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) + return buf +} -- cgit v1.2.3-54-g00ecf