Golang Writer.Flush方法代码示例

func requestsSender(w *bufio.Writer, requests <-chan tasker, responses chan<- tasker, c net.Conn, done *sync.WaitGroup) {
	defer done.Done()
	defer w.Flush()
	defer close(responses)
	scratchBuf := make([]byte, 0, 1024)
	for {
		var t tasker
		var ok bool

		// Flush w only if there are no pending requests.
		select {
		case t, ok = <-requests:
		default:
			w.Flush()
			t, ok = <-requests
		}
		if !ok {
			break
		}
		if !t.WriteRequest(w, &scratchBuf) {
			t.Done(false)
			break
		}
		responses <- t
	}
}

/*
Handhake described in (soon obsolete)
draft-hixie-thewebsocket-protocol-75.
*/
func draft75handshake(resourceName, host, origin, location, protocol string, br *bufio.Reader, bw *bufio.Writer) (err os.Error) {
	bw.WriteString("GET " + resourceName + " HTTP/1.1\r\n")
	bw.WriteString("Upgrade: WebSocket\r\n")
	bw.WriteString("Connection: Upgrade\r\n")
	bw.WriteString("Host: " + host + "\r\n")
	bw.WriteString("Origin: " + origin + "\r\n")
	if protocol != "" {
		bw.WriteString("WebSocket-Protocol: " + protocol + "\r\n")
	}
	bw.WriteString("\r\n")
	bw.Flush()
	resp, err := http.ReadResponse(br, "GET")
	if err != nil {
		return
	}
	if resp.Status != "101 Web Socket Protocol Handshake" {
		return ErrBadStatus
	}
	if resp.Header["Upgrade"] != "WebSocket" ||
		resp.Header["Connection"] != "Upgrade" {
		return ErrBadUpgrade
	}
	if resp.Header["Websocket-Origin"] != origin {
		return ErrBadWebSocketOrigin
	}
	if resp.Header["Websocket-Location"] != location {
		return ErrBadWebSocketLocation
	}
	if protocol != "" && resp.Header["Websocket-Protocol"] != protocol {
		return ErrBadWebSocketProtocol
	}
	return
}

func (r Resolver) outputResults(w *bufio.Writer, results gresults) {
	var zip, city, state, stateName, county, country, countryName string
	var latitude, longitude float32

	var comp addressComponent
	var err error
	for _, res := range results.Results {
		if comp, err = res.findAddressComponent(zipType); err == nil {
			zip = comp.LongName
		}
		if comp, err = res.findAddressComponent(cityType); err == nil {
			city = comp.LongName
		}
		if comp, err = res.findAddressComponent(countyType); err == nil {
			county = comp.LongName
		}
		if comp, err = res.findAddressComponent(stateType); err == nil {
			state = strings.ToUpper(comp.ShortName)
			stateName = comp.LongName
		}
		if comp, err = res.findAddressComponent(countryType); err == nil {
			country = strings.ToUpper(comp.ShortName)
			countryName = comp.LongName
		}
		latitude = res.Geometry.Location.Lat
		longitude = res.Geometry.Location.Lng
	}
	w.WriteString(fmt.Sprintf("%v,\"%v\",\"%v\",\"%v\",\"%v\",\"%v\",\"%v\",%v,%v\n", country, zip, city, state, stateName, county, countryName, latitude, longitude))
	w.Flush()
}

// NewStreamReader returns a reader, which replays all the data generated by sw.
//
// The returned reader may be passed to Response.SetBodyStream.
//
// Close must be called on the returned reader after all the required data
// has been read. Otherwise goroutine leak may occur.
//
// See also Response.SetBodyStreamWriter.
func NewStreamReader(sw StreamWriter) io.ReadCloser {
	pc := fasthttputil.NewPipeConns()
	pw := pc.Conn1()
	pr := pc.Conn2()

	var bw *bufio.Writer
	v := streamWriterBufPool.Get()
	if v == nil {
		bw = bufio.NewWriter(pw)
	} else {
		bw = v.(*bufio.Writer)
		bw.Reset(pw)
	}

	go func() {
		defer func() {
			if r := recover(); r != nil {
				defaultLogger.Printf("panic in StreamWriter: %s\nStack trace:\n%s", r, debug.Stack())
			}
		}()

		sw(bw)
		bw.Flush()
		pw.Close()

		streamWriterBufPool.Put(bw)
	}()

	return pr
}

func (conn *Connection) writer() {
	var w *bufio.Writer
	var err error
	for {
		var packet []byte
		select {
		case packet = <-conn.packets:
		default:
			if w = conn.w; w != nil {
				if err := w.Flush(); err != nil {
					conn.closeConnection(err)
				}
			}
			select {
			case packet = <-conn.packets:
			case <-conn.control:
				return
			}
		}
		if packet == nil {
			return
		}
		if w = conn.w; w == nil {
			if _, w, err = conn.createConnection(); err != nil {
				return
			}
		}
		if err := write(w, packet); err != nil {
			conn.closeConnection(err)
			continue
		}
	}
}

func (t *TcpPlayer) sendUpdates(w *bufio.Writer, wg *sync.WaitGroup) {
	defer wg.Done()

	enc := json.NewEncoder(w)

	lastTurnSent := -1
	for update := range t.update {
		t.stateL.Lock()
		t.state = update
		t.stateL.Unlock()

		if update.Turn == lastTurnSent {
			continue
		}

		if err := enc.Encode(update); err != nil {
			t.l.Errorf("[TCP] sending update to player, %v", err)
			return
		}

		if _, err := w.WriteRune('\n'); err != nil {
			t.l.Errorf("[TCP] sending EOL to player, %v", err)
			return
		}

		if err := w.Flush(); err != nil {
			t.l.Errorf("[TCP] flushing update to player, %v", err)
			return
		}
		lastTurnSent = update.Turn
	}
}

func WriteProto(wr *bufio.Writer, proto *Proto) (err error) {
	// write
	if err = binary.Write(wr, binary.BigEndian, uint32(rawHeaderLen)+uint32(len(proto.Body))); err != nil {
		return
	}
	if err = binary.Write(wr, binary.BigEndian, rawHeaderLen); err != nil {
		return
	}
	if err = binary.Write(wr, binary.BigEndian, proto.Ver); err != nil {
		return
	}
	if err = binary.Write(wr, binary.BigEndian, proto.Operation); err != nil {
		return
	}
	if err = binary.Write(wr, binary.BigEndian, proto.SeqId); err != nil {
		return
	}
	if proto.Body != nil {
		log.Debug("cipher body: %v", proto.Body)
		if err = binary.Write(wr, binary.BigEndian, proto.Body); err != nil {
			return
		}
	}
	err = wr.Flush()
	return
}

func writeErrorResponseHeader(w *bufio.Writer, opcode uint8, status uint16, opaque uint32) error {
	header := resHeadPool.Get().(ResponseHeader)

	header.Magic = MagicResponse
	header.Opcode = opcode
	header.KeyLength = uint16(0)
	header.ExtraLength = uint8(0)
	header.DataType = uint8(0)
	header.Status = status
	header.TotalBodyLength = uint32(0)
	header.OpaqueToken = opaque
	header.CASToken = uint64(0)

	if err := writeResponseHeader(w, header); err != nil {
		resHeadPool.Put(header)
		return err
	}

	if err := w.Flush(); err != nil {
		resHeadPool.Put(header)
		return err
	}

	metrics.IncCounterBy(common.MetricBytesWrittenRemote, resHeaderLen)
	resHeadPool.Put(header)

	return nil
}

func deleteGroup(r *bufio.Reader, w *bufio.Writer, args []string, thisUser *utils.User) (err error) {

	if len(args) < 2 {
		fmt.Println("Not enough arguments for call to group-remove:")
		fmt.Println("Format should be: delete-group GID")
		return nil
	}

	err = w.WriteByte(24)
	w.Flush()
	if err != nil {
		return err
	}

	w.WriteString(args[1] + "\n")
	w.Flush()

	// get success (1) or fail (2)
	success, _ := r.ReadByte()
	if success != 1 {
		fmt.Println("You cannot remove this group. Does it exist/are you the owner?")
		return err
	}

	fmt.Println("Removed: " + args[1])

	return err
}

// auth for goim handshake with client, use rsa & aes.
func (server *Server) authTCP(rr *bufio.Reader, wr *bufio.Writer, ch *Channel) (subKey string, heartbeat time.Duration, err error) {
	var p *Proto
	// WARN
	// don't adv the cli proto, after auth simply discard it.
	if p, err = ch.CliProto.Set(); err != nil {
		return
	}
	if err = server.readTCPRequest(rr, p); err != nil {
		return
	}
	if p.Operation != define.OP_AUTH {
		log.Warn("auth operation not valid: %d", p.Operation)
		err = ErrOperation
		return
	}
	if subKey, ch.RoomId, heartbeat, err = server.operator.Connect(p); err != nil {
		log.Error("operator.Connect error(%v)", err)
		return
	}
	p.Body = nil
	p.Operation = define.OP_AUTH_REPLY
	if err = server.writeTCPResponse(wr, p); err != nil {
		log.Error("[%s] server.sendTCPResponse() error(%v)", subKey, err)
	}
	err = wr.Flush()
	return
}

func writeSuccessResponseHeader(w *bufio.Writer, opcode uint8, keyLength, extraLength,
	totalBodyLength int, opaque uint32, flush bool) error {

	header := resHeadPool.Get().(ResponseHeader)

	header.Magic = MagicResponse
	header.Opcode = opcode
	header.KeyLength = uint16(keyLength)
	header.ExtraLength = uint8(extraLength)
	header.DataType = uint8(0)
	header.Status = StatusSuccess
	header.TotalBodyLength = uint32(totalBodyLength)
	header.OpaqueToken = opaque
	header.CASToken = uint64(0)

	if err := writeResponseHeader(w, header); err != nil {
		resHeadPool.Put(header)
		return err
	}

	if flush {
		if err := w.Flush(); err != nil {
			resHeadPool.Put(header)
			return err
		}
	}

	metrics.IncCounterBy(common.MetricBytesWrittenRemote, resHeaderLen)
	resHeadPool.Put(header)

	return nil
}

func testWriteMatch(t *testing.T, obj writeObject, expected string) {
	var buf *bytes.Buffer = bytes.NewBuffer(nil)
	var wr *bufio.Writer = bufio.NewWriter(buf)
	var err error

	err = obj.write(wr)
	if err != nil {
		t.Errorf("Error: %#v", err)
		return
	}

	err = wr.Flush()
	if err != nil {
		t.Errorf("Error: %#v", err)
		return
	}

	var bExpected []byte = []byte(expected)
	var bActual []byte = buf.Bytes()

	if !bytes.Equal(bExpected, bActual) {
		t.Errorf("Expected: %#v, got: %#v", string(bExpected), string(bActual))
		return
	}
}

func readFile(path string) {
	var w *bufio.Writer = bufio.NewWriter(os.Stdout)
	defer w.Flush()

	fmt.Fprintf(w, "read file start: %s\n", path)

	file, err := os.OpenFile(path, os.O_RDONLY, 0666) // 打开文件

	if err != nil {
		fmt.Printf("open file err: %v\n", err)
		return
	}

	defer file.Close() // 延时关闭文件

	var buff []byte = make([]byte, 1024)
	var r *bufio.Reader = bufio.NewReader(file)

	for {
		n, _ := r.Read(buff)
		if n <= 0 {
			fmt.Fprintf(w, "read file end: %s %d\n", path, n)
			return
		}

		w.Write(buff[0:n])
	}
}

func marshalText(w io.Writer, pb Message, compact bool) error {
	val := reflect.ValueOf(pb)
	if pb == nil || val.IsNil() {
		w.Write([]byte("<nil>"))
		return nil
	}
	var bw *bufio.Writer
	ww, ok := w.(writer)
	if !ok {
		bw = bufio.NewWriter(w)
		ww = bw
	}
	aw := &textWriter{
		w:        ww,
		complete: true,
		compact:  compact,
	}

	// Dereference the received pointer so we don't have outer < and >.
	v := reflect.Indirect(val)
	if err := writeStruct(aw, v); err != nil {
		return err
	}
	if bw != nil {
		return bw.Flush()
	}
	return nil
}

func HandshakeSample(c net.Conn, br *bufio.Reader, bw *bufio.Writer, timeout time.Duration) (err error) {
	defer func() {
		if r := recover(); r != nil {
			err = r.(error)
		}
	}()
	// Send C0+C1
	err = bw.WriteByte(0x03)
	c1 := CreateRandomBlock(RTMP_SIG_SIZE)
	for i := 0; i < 8; i++ {
		c1[i] = 0
	}
	bw.Write(c1)
	err = bw.Flush()
	CheckError(err, "Handshake() Flush C0+C1")
	// Read S0+S1+S2
	s0, err := br.ReadByte()
	CheckError(err, "Handshake() Read S0")
	if s0 != 0x03 {
		return errors.New(fmt.Sprintf("Handshake() Got S0: %x", s0))
	}
	s1 := make([]byte, RTMP_SIG_SIZE)
	_, err = io.ReadAtLeast(br, s1, RTMP_SIG_SIZE)
	CheckError(err, "Handshake() Read S1")
	bw.Write(s1)
	err = bw.Flush()
	CheckError(err, "Handshake() Flush C2")
	_, err = io.ReadAtLeast(br, s1, RTMP_SIG_SIZE)
	CheckError(err, "Handshake() Read S2")
	return
}