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Add gorilla/websocket to vendor folder
This commit is contained in:
Faissal Elamraoui
951
vendor/github.com/gorilla/websocket/conn.go
generated
vendored
Normal file
951
vendor/github.com/gorilla/websocket/conn.go
generated
vendored
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@ -0,0 +1,951 @@
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// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package websocket
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import (
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"bufio"
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"encoding/binary"
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"errors"
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"io"
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"io/ioutil"
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"math/rand"
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"net"
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"strconv"
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"time"
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"unicode/utf8"
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)
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const (
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maxFrameHeaderSize = 2 + 8 + 4 // Fixed header + length + mask
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maxControlFramePayloadSize = 125
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finalBit = 1 << 7
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maskBit = 1 << 7
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writeWait = time.Second
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defaultReadBufferSize = 4096
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defaultWriteBufferSize = 4096
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continuationFrame = 0
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noFrame = -1
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)
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// Close codes defined in RFC 6455, section 11.7.
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const (
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CloseNormalClosure = 1000
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CloseGoingAway = 1001
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CloseProtocolError = 1002
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CloseUnsupportedData = 1003
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CloseNoStatusReceived = 1005
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CloseAbnormalClosure = 1006
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CloseInvalidFramePayloadData = 1007
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ClosePolicyViolation = 1008
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CloseMessageTooBig = 1009
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CloseMandatoryExtension = 1010
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CloseInternalServerErr = 1011
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CloseServiceRestart = 1012
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CloseTryAgainLater = 1013
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CloseTLSHandshake = 1015
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)
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// The message types are defined in RFC 6455, section 11.8.
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const (
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// TextMessage denotes a text data message. The text message payload is
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// interpreted as UTF-8 encoded text data.
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TextMessage = 1
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// BinaryMessage denotes a binary data message.
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BinaryMessage = 2
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// CloseMessage denotes a close control message. The optional message
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// payload contains a numeric code and text. Use the FormatCloseMessage
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// function to format a close message payload.
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CloseMessage = 8
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// PingMessage denotes a ping control message. The optional message payload
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// is UTF-8 encoded text.
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PingMessage = 9
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// PongMessage denotes a ping control message. The optional message payload
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// is UTF-8 encoded text.
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PongMessage = 10
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)
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// ErrCloseSent is returned when the application writes a message to the
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// connection after sending a close message.
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var ErrCloseSent = errors.New("websocket: close sent")
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// ErrReadLimit is returned when reading a message that is larger than the
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// read limit set for the connection.
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var ErrReadLimit = errors.New("websocket: read limit exceeded")
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// netError satisfies the net Error interface.
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type netError struct {
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msg string
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temporary bool
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timeout bool
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}
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func (e *netError) Error() string { return e.msg }
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func (e *netError) Temporary() bool { return e.temporary }
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func (e *netError) Timeout() bool { return e.timeout }
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// CloseError represents close frame.
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type CloseError struct {
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// Code is defined in RFC 6455, section 11.7.
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Code int
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// Text is the optional text payload.
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Text string
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}
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func (e *CloseError) Error() string {
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s := []byte("websocket: close ")
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s = strconv.AppendInt(s, int64(e.Code), 10)
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switch e.Code {
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case CloseNormalClosure:
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s = append(s, " (normal)"...)
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case CloseGoingAway:
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s = append(s, " (going away)"...)
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case CloseProtocolError:
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s = append(s, " (protocol error)"...)
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case CloseUnsupportedData:
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s = append(s, " (unsupported data)"...)
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case CloseNoStatusReceived:
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s = append(s, " (no status)"...)
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case CloseAbnormalClosure:
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s = append(s, " (abnormal closure)"...)
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case CloseInvalidFramePayloadData:
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s = append(s, " (invalid payload data)"...)
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case ClosePolicyViolation:
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s = append(s, " (policy violation)"...)
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case CloseMessageTooBig:
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s = append(s, " (message too big)"...)
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case CloseMandatoryExtension:
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s = append(s, " (mandatory extension missing)"...)
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case CloseInternalServerErr:
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s = append(s, " (internal server error)"...)
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case CloseTLSHandshake:
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s = append(s, " (TLS handshake error)"...)
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}
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if e.Text != "" {
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s = append(s, ": "...)
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s = append(s, e.Text...)
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}
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return string(s)
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}
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// IsCloseError returns boolean indicating whether the error is a *CloseError
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// with one of the specified codes.
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func IsCloseError(err error, codes ...int) bool {
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if e, ok := err.(*CloseError); ok {
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for _, code := range codes {
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if e.Code == code {
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return true
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}
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}
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}
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return false
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}
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// IsUnexpectedCloseError returns boolean indicating whether the error is a
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// *CloseError with a code not in the list of expected codes.
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func IsUnexpectedCloseError(err error, expectedCodes ...int) bool {
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if e, ok := err.(*CloseError); ok {
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for _, code := range expectedCodes {
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if e.Code == code {
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return false
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}
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}
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return true
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}
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return false
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}
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var (
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errWriteTimeout = &netError{msg: "websocket: write timeout", timeout: true, temporary: true}
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errUnexpectedEOF = &CloseError{Code: CloseAbnormalClosure, Text: io.ErrUnexpectedEOF.Error()}
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errBadWriteOpCode = errors.New("websocket: bad write message type")
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errWriteClosed = errors.New("websocket: write closed")
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errInvalidControlFrame = errors.New("websocket: invalid control frame")
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)
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func hideTempErr(err error) error {
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if e, ok := err.(net.Error); ok && e.Temporary() {
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err = &netError{msg: e.Error(), timeout: e.Timeout()}
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}
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return err
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}
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func isControl(frameType int) bool {
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return frameType == CloseMessage || frameType == PingMessage || frameType == PongMessage
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}
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func isData(frameType int) bool {
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return frameType == TextMessage || frameType == BinaryMessage
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}
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var validReceivedCloseCodes = map[int]bool{
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// see http://www.iana.org/assignments/websocket/websocket.xhtml#close-code-number
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CloseNormalClosure: true,
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CloseGoingAway: true,
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CloseProtocolError: true,
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CloseUnsupportedData: true,
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CloseNoStatusReceived: false,
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CloseAbnormalClosure: false,
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CloseInvalidFramePayloadData: true,
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ClosePolicyViolation: true,
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CloseMessageTooBig: true,
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CloseMandatoryExtension: true,
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CloseInternalServerErr: true,
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CloseServiceRestart: true,
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CloseTryAgainLater: true,
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CloseTLSHandshake: false,
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}
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func isValidReceivedCloseCode(code int) bool {
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return validReceivedCloseCodes[code] || (code >= 3000 && code <= 4999)
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}
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func maskBytes(key [4]byte, pos int, b []byte) int {
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for i := range b {
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b[i] ^= key[pos&3]
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pos++
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}
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return pos & 3
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}
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func newMaskKey() [4]byte {
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n := rand.Uint32()
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return [4]byte{byte(n), byte(n >> 8), byte(n >> 16), byte(n >> 24)}
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}
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// Conn represents a WebSocket connection.
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type Conn struct {
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conn net.Conn
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isServer bool
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subprotocol string
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// Write fields
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mu chan bool // used as mutex to protect write to conn and closeSent
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closeSent bool // true if close message was sent
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// Message writer fields.
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writeErr error
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writeBuf []byte // frame is constructed in this buffer.
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writePos int // end of data in writeBuf.
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writeFrameType int // type of the current frame.
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writeDeadline time.Time
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isWriting bool // for best-effort concurrent write detection
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messageWriter *messageWriter // the current writer
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// Read fields
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readErr error
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br *bufio.Reader
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readRemaining int64 // bytes remaining in current frame.
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readFinal bool // true the current message has more frames.
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readLength int64 // Message size.
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readLimit int64 // Maximum message size.
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readMaskPos int
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readMaskKey [4]byte
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handlePong func(string) error
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handlePing func(string) error
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readErrCount int
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messageReader *messageReader // the current reader
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}
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func newConn(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int) *Conn {
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mu := make(chan bool, 1)
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mu <- true
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if readBufferSize == 0 {
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readBufferSize = defaultReadBufferSize
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}
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if readBufferSize < maxControlFramePayloadSize {
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readBufferSize = maxControlFramePayloadSize
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}
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if writeBufferSize == 0 {
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writeBufferSize = defaultWriteBufferSize
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}
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c := &Conn{
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isServer: isServer,
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br: bufio.NewReaderSize(conn, readBufferSize),
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conn: conn,
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mu: mu,
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readFinal: true,
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writeBuf: make([]byte, writeBufferSize+maxFrameHeaderSize),
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writeFrameType: noFrame,
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writePos: maxFrameHeaderSize,
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}
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c.SetPingHandler(nil)
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c.SetPongHandler(nil)
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return c
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}
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// Subprotocol returns the negotiated protocol for the connection.
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func (c *Conn) Subprotocol() string {
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return c.subprotocol
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}
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// Close closes the underlying network connection without sending or waiting for a close frame.
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func (c *Conn) Close() error {
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return c.conn.Close()
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}
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// LocalAddr returns the local network address.
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func (c *Conn) LocalAddr() net.Addr {
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return c.conn.LocalAddr()
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}
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// RemoteAddr returns the remote network address.
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func (c *Conn) RemoteAddr() net.Addr {
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return c.conn.RemoteAddr()
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}
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// Write methods
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func (c *Conn) write(frameType int, deadline time.Time, bufs ...[]byte) error {
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<-c.mu
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defer func() { c.mu <- true }()
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if c.closeSent {
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return ErrCloseSent
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} else if frameType == CloseMessage {
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c.closeSent = true
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}
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c.conn.SetWriteDeadline(deadline)
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for _, buf := range bufs {
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if len(buf) > 0 {
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n, err := c.conn.Write(buf)
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if n != len(buf) {
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// Close on partial write.
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c.conn.Close()
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}
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if err != nil {
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return err
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}
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}
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}
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return nil
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}
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// WriteControl writes a control message with the given deadline. The allowed
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// message types are CloseMessage, PingMessage and PongMessage.
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func (c *Conn) WriteControl(messageType int, data []byte, deadline time.Time) error {
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if !isControl(messageType) {
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return errBadWriteOpCode
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}
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if len(data) > maxControlFramePayloadSize {
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return errInvalidControlFrame
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}
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b0 := byte(messageType) | finalBit
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b1 := byte(len(data))
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if !c.isServer {
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b1 |= maskBit
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}
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buf := make([]byte, 0, maxFrameHeaderSize+maxControlFramePayloadSize)
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buf = append(buf, b0, b1)
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if c.isServer {
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buf = append(buf, data...)
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} else {
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key := newMaskKey()
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||||
buf = append(buf, key[:]...)
|
||||
buf = append(buf, data...)
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||||
maskBytes(key, 0, buf[6:])
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||||
}
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||||
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||||
d := time.Hour * 1000
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||||
if !deadline.IsZero() {
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d = deadline.Sub(time.Now())
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if d < 0 {
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return errWriteTimeout
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}
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}
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||||
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timer := time.NewTimer(d)
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select {
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case <-c.mu:
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||||
timer.Stop()
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case <-timer.C:
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||||
return errWriteTimeout
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||||
}
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defer func() { c.mu <- true }()
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if c.closeSent {
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return ErrCloseSent
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||||
} else if messageType == CloseMessage {
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c.closeSent = true
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||||
}
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||||
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||||
c.conn.SetWriteDeadline(deadline)
|
||||
n, err := c.conn.Write(buf)
|
||||
if n != 0 && n != len(buf) {
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||||
c.conn.Close()
|
||||
}
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||||
return hideTempErr(err)
|
||||
}
|
||||
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||||
// 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.
|
||||
func (c *Conn) NextWriter(messageType int) (io.WriteCloser, error) {
|
||||
if c.writeErr != nil {
|
||||
return nil, c.writeErr
|
||||
}
|
||||
|
||||
if c.writeFrameType != noFrame {
|
||||
if err := c.flushFrame(true, nil); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
|
||||
if !isControl(messageType) && !isData(messageType) {
|
||||
return nil, errBadWriteOpCode
|
||||
}
|
||||
|
||||
c.writeFrameType = messageType
|
||||
w := &messageWriter{c}
|
||||
c.messageWriter = w
|
||||
return w, nil
|
||||
}
|
||||
|
||||
func (c *Conn) flushFrame(final bool, extra []byte) error {
|
||||
length := c.writePos - maxFrameHeaderSize + len(extra)
|
||||
|
||||
// Check for invalid control frames.
|
||||
if isControl(c.writeFrameType) &&
|
||||
(!final || length > maxControlFramePayloadSize) {
|
||||
c.messageWriter = nil
|
||||
c.writeFrameType = noFrame
|
||||
c.writePos = maxFrameHeaderSize
|
||||
return errInvalidControlFrame
|
||||
}
|
||||
|
||||
b0 := byte(c.writeFrameType)
|
||||
if final {
|
||||
b0 |= finalBit
|
||||
}
|
||||
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:c.writePos])
|
||||
if len(extra) > 0 {
|
||||
c.writeErr = errors.New("websocket: internal error, extra used in client mode")
|
||||
return c.writeErr
|
||||
}
|
||||
}
|
||||
|
||||
// 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
|
||||
|
||||
c.writeErr = c.write(c.writeFrameType, c.writeDeadline, c.writeBuf[framePos:c.writePos], extra)
|
||||
|
||||
if !c.isWriting {
|
||||
panic("concurrent write to websocket connection")
|
||||
}
|
||||
c.isWriting = false
|
||||
|
||||
// Setup for next frame.
|
||||
c.writePos = maxFrameHeaderSize
|
||||
c.writeFrameType = continuationFrame
|
||||
if final {
|
||||
c.messageWriter = nil
|
||||
c.writeFrameType = noFrame
|
||||
}
|
||||
return c.writeErr
|
||||
}
|
||||
|
||||
type messageWriter struct{ c *Conn }
|
||||
|
||||
func (w *messageWriter) err() error {
|
||||
c := w.c
|
||||
if c.messageWriter != w {
|
||||
return errWriteClosed
|
||||
}
|
||||
if c.writeErr != nil {
|
||||
return c.writeErr
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func (w *messageWriter) ncopy(max int) (int, error) {
|
||||
n := len(w.c.writeBuf) - w.c.writePos
|
||||
if n <= 0 {
|
||||
if err := w.c.flushFrame(false, nil); err != nil {
|
||||
return 0, err
|
||||
}
|
||||
n = len(w.c.writeBuf) - w.c.writePos
|
||||
}
|
||||
if n > max {
|
||||
n = max
|
||||
}
|
||||
return n, nil
|
||||
}
|
||||
|
||||
func (w *messageWriter) write(final bool, p []byte) (int, error) {
|
||||
if err := w.err(); err != nil {
|
||||
return 0, err
|
||||
}
|
||||
|
||||
if len(p) > 2*len(w.c.writeBuf) && w.c.isServer {
|
||||
// Don't buffer large messages.
|
||||
err := w.c.flushFrame(final, 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.c.writePos:], p[:n])
|
||||
w.c.writePos += n
|
||||
p = p[n:]
|
||||
}
|
||||
return nn, nil
|
||||
}
|
||||
|
||||
func (w *messageWriter) Write(p []byte) (int, error) {
|
||||
return w.write(false, p)
|
||||
}
|
||||
|
||||
func (w *messageWriter) WriteString(p string) (int, error) {
|
||||
if err := w.err(); err != nil {
|
||||
return 0, 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.c.writePos:], p[:n])
|
||||
w.c.writePos += n
|
||||
p = p[n:]
|
||||
}
|
||||
return nn, nil
|
||||
}
|
||||
|
||||
func (w *messageWriter) ReadFrom(r io.Reader) (nn int64, err error) {
|
||||
if err := w.err(); err != nil {
|
||||
return 0, err
|
||||
}
|
||||
for {
|
||||
if w.c.writePos == len(w.c.writeBuf) {
|
||||
err = w.c.flushFrame(false, nil)
|
||||
if err != nil {
|
||||
break
|
||||
}
|
||||
}
|
||||
var n int
|
||||
n, err = r.Read(w.c.writeBuf[w.c.writePos:])
|
||||
w.c.writePos += n
|
||||
nn += int64(n)
|
||||
if err != nil {
|
||||
if err == io.EOF {
|
||||
err = nil
|
||||
}
|
||||
break
|
||||
}
|
||||
}
|
||||
return nn, err
|
||||
}
|
||||
|
||||
func (w *messageWriter) Close() error {
|
||||
if err := w.err(); err != nil {
|
||||
return err
|
||||
}
|
||||
return w.c.flushFrame(true, nil)
|
||||
}
|
||||
|
||||
// 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 {
|
||||
w, err := c.NextWriter(messageType)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
if _, ok := w.(*messageWriter); ok && c.isServer {
|
||||
// Optimize write as a single frame.
|
||||
n := copy(c.writeBuf[c.writePos:], data)
|
||||
c.writePos += n
|
||||
data = data[n:]
|
||||
err = c.flushFrame(true, data)
|
||||
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)
|
||||
reserved := int((p[0] >> 4) & 0x7)
|
||||
mask := p[1]&maskBit != 0
|
||||
c.readRemaining = int64(p[1] & 0x7f)
|
||||
|
||||
if reserved != 0 {
|
||||
return noFrame, c.handleProtocolError("unexpected reserved bits " + strconv.Itoa(reserved))
|
||||
}
|
||||
|
||||
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:
|
||||
echoMessage := []byte{}
|
||||
closeCode := CloseNoStatusReceived
|
||||
closeText := ""
|
||||
if len(payload) >= 2 {
|
||||
echoMessage = 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")
|
||||
}
|
||||
}
|
||||
c.WriteControl(CloseMessage, echoMessage, time.Now().Add(writeWait))
|
||||
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) {
|
||||
|
||||
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 {
|
||||
r := &messageReader{c}
|
||||
c.messageReader = r
|
||||
return frameType, r, 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
|
||||
}
|
||||
|
||||
// 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 frame to the peer
|
||||
// and returns ErrReadLimit to the application.
|
||||
func (c *Conn) SetReadLimit(limit int64) {
|
||||
c.readLimit = limit
|
||||
}
|
||||
|
||||
// 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 frame application data. The default
|
||||
// ping handler sends a pong to the peer.
|
||||
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 frame application data. The default
|
||||
// pong handler does nothing.
|
||||
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
|
||||
}
|
||||
|
||||
// FormatCloseMessage formats closeCode and text as a WebSocket close message.
|
||||
func FormatCloseMessage(closeCode int, text string) []byte {
|
||||
buf := make([]byte, 2+len(text))
|
||||
binary.BigEndian.PutUint16(buf, uint16(closeCode))
|
||||
copy(buf[2:], text)
|
||||
return buf
|
||||
}
|
||||
Reference in New Issue
Block a user