func pingThread(pingConn *net.UDPConn) {
p := []byte("1")
for {
_, _ = pingConn.Write(p)
time.Sleep(time.Millisecond * 250)
}
}
// Handshake performs data exchange between DHT client and server
func (dht *DHTClient) Handshake(conn *net.UDPConn) error {
// Handshake
var req DHTMessage
req.ID = "0"
req.Query = PacketVersion
req.Command = DhtCmdConn
// TODO: rename Port to something more clear
req.Arguments = fmt.Sprintf("%d", dht.P2PPort)
req.Payload = dht.NetworkHash
for _, ip := range dht.IPList {
req.Arguments = req.Arguments + "|" + ip.String()
}
var b bytes.Buffer
if err := bencode.Marshal(&b, req); err != nil {
Log(Error, "Failed to Marshal bencode %v", err)
conn.Close()
return err
}
// TODO: Optimize types here
msg := b.String()
if dht.Shutdown {
return nil
}
_, err := conn.Write([]byte(msg))
if err != nil {
Log(Error, "Failed to send packet: %v", err)
conn.Close()
return err
}
return nil
}
func SendAChunk(conn *net.UDPConn, addr *net.UDPAddr, isServer bool) {
var n2 int
var err error
var datablock []byte
//Send the chink that we have in the Block (it is either the previous one being retransmitted or a the next one
var opcode = "\x00\x03" //Data packet
var blocknumBytes = make([]byte, 2)
binary.BigEndian.PutUint16(blocknumBytes, uint16(chunk.blocknum))
datablock = append(datablock, []byte(opcode)...)
datablock = append(datablock, blocknumBytes...)
fmt.Println("Stage 2: Datablock ", datablock)
if chunk.nbytes < 512 {
// make a slice of size chunk.nbytes and copy the data into it
tempbuf := make([]byte, chunk.nbytes)
n1 := copy(tempbuf, chunk.buf[0:chunk.nbytes])
fmt.Println("Copied %d bytes to the last chunk being sent", n1)
datablock = append(datablock, tempbuf...)
} else {
datablock = append(datablock, chunk.buf...)
}
fmt.Println("sending datablock", datablock)
if isServer {
n2, err = conn.WriteToUDP(datablock, addr)
} else {
n2, err = conn.Write(datablock)
}
fmt.Println("Number of Bytes sent is ", n2)
if err != nil {
fmt.Printf("Couldn't send datablock %v", err)
}
}
// udpKeepAlive sends a udp packet to keep the udp connection open
// This is still a bit of a "proof of concept"
func (v *VoiceConnection) udpKeepAlive(udpConn *net.UDPConn, close <-chan struct{}, i time.Duration) {
if udpConn == nil || close == nil {
return
}
var err error
var sequence uint64
packet := make([]byte, 8)
ticker := time.NewTicker(i)
for {
binary.LittleEndian.PutUint64(packet, sequence)
sequence++
_, err = udpConn.Write(packet)
if err != nil {
v.log(LogError, "write error, %s", err)
return
}
select {
case <-ticker.C:
// continue loop and send keepalive
case <-close:
return
}
}
}
func messageServer(c *net.UDPConn, message string) {
log.Printf("Write to server: %q", message)
n, err := c.Write([]byte(message))
if n == 0 || err != nil {
log.Fatalf("WriteToUDP failed: %v", err.Error())
}
}
func PutRecv(conn *net.UDPConn, context *UdpContext) int {
file := context.file
buffer := make([]byte, 1024)
read, err := conn.Read(buffer)
if err == io.EOF {
break
}
if err != nil {
fmt.Printf("Error reading from network: %s. Aborting transfer\n", err)
return
}
_, err = file.Write(buffer[:read])
if err != nil {
fmt.Println("Error writing to file; aborting transfer")
return
}
_, err = conn.Write([]byte("put-ack"))
if err != nil {
fmt.Println("Error writing ack; aborting transfer")
return
}
return read
}
func (c *TFTPServer) sendAck(conn *net.UDPConn, tid string) {
pkt := &TFTPAckPkt{Opcode: OpcodeACK, Block: c.Connections[tid].block}
conn.SetWriteDeadline(time.Now().Add(1 * time.Second))
if _, err := conn.Write(pkt.Pack()); err != nil {
log.Println(err)
}
}
/* Send file data to TFTP server in DATA packets. */
func sendData(conn *net.UDPConn, filename string) {
input, err := os.Open(filename)
checkError(err)
buf := make([]byte, 512)
for {
n, err := input.Read(buf)
checkError(err)
data := make([]byte, 516)
copy(data, DATA)
copy(data[4:], buf)
_, err = conn.Write(data)
checkError(err)
if n < len(buf) {
finalAck := make([]byte, 4)
for !bytes.Equal(finalAck[0:2], ACK) {
_, _, err := conn.ReadFromUDP(finalAck)
checkError(err)
}
break
}
}
}
// sendDataPacket sends the given data packet to the connected client
// and waits for the correct ACK, or times out
func sendDataPacket(s *Server, d *pkt.DataPacket, con *net.UDPConn) error {
_, err := con.Write(d.Bytes())
if err != nil {
return err
}
// Now wait for the ACK...
maxtimeout := time.After(AckTimeout)
ackch := make(chan error)
// Move it to its own function
go func() {
ack := make([]byte, 256)
for {
n, _, err := con.ReadFromUDP(ack)
if err != nil {
ackch <- err
return
}
pack, err := pkt.ParsePacket(ack[:n])
if err != nil {
ackch <- err
return
}
// Check packet type
ackpack, ok := pack.(*pkt.AckPacket)
if !ok {
ackch <- pkt.ErrPacketType
return
}
if ackpack.GetBlocknum() != d.BlockNum {
s.Logger.Warning("got ack(%d) but expected ack(%d)\n", d.BlockNum, ackpack.GetBlocknum())
continue
}
ackch <- nil
return
}
}()
// Loop and retransmit until ack or timeout
retransmit := time.After(RetransmitTime)
for {
select {
case <-maxtimeout:
return ErrTimeout
case <-retransmit:
s.Logger.Warning("Retransmit")
_, err := con.Write(d.Bytes())
if err != nil {
return err
}
retransmit = time.After(RetransmitTime)
case err := <-ackch:
return err
}
}
}
//TickServer 将 c 传入的数据广播到局域网
func (server *UDPServer) TickServer(c <-chan []byte) (err error) {
var conn *net.UDPConn
fmt.Println("start TickServer")
server.slock.Lock()
for i := 0; i < 3; i++ {
conn, err = net.DialUDP("udp", server.sendAddr, server.bcastAddr)
if err == nil {
break
} else {
fmt.Println("DialUDP err:", err)
}
time.Sleep(3 * time.Millisecond)
}
defer func() {
if err := recover(); err != nil {
fmt.Println("MY:", err)
}
}()
stop := false
p := &packet.NoticePacket{packet.STATE_OFFLINE, []byte(""), []byte("")}
buf, _ := json.Marshal(p) //make the init packet
tickchan := make(chan []byte, 128)
go func(c chan []byte) { //tick function
defer func() {
conn.Close()
server.slock.Unlock()
fmt.Println("stop udp TickServer FINISH.")
}()
for {
if stop {
return
}
//fmt.Println("send: ", string(buf))
_, err = conn.Write(buf)
errorCheck(err)
time.Sleep(time.Duration(server.tick) * time.Millisecond)
}
}(tickchan)
for {
timeout := make(chan bool)
go func() {
time.Sleep(5000 * time.Millisecond)
timeout <- true
}()
select {
case buf = <-c:
//tickchan <- buf
case <-timeout: //超时检测
case <-server.sexitchan: //退出
//server.slock.Lock()
fmt.Println("stop udp TickServer....")
stop = true
return nil
}
}
return nil
}
func sendUDP(udpConn *net.UDPConn) {
sendString := `Hello World!/usr/local/go/bin/go build -o /Users/jiaxun/IdeaProjects/socketTest/MacPing /Users/jiaxun/IdeaProjects/socketTest/main.go /Users/jiaxun/IdeaProjects/socketTest/MacPing`
_, err := udpConn.Write([]byte(sendString))
if err != nil {
fmt.Println(err.Error())
return
}
}
func myNetwork_clientSend(c *net.UDPConn, packet []byte) {
if rand.Intn(4) != 10 { //25% failure rate
c.Write(packet)
} else {
log.Println("Dropped Packet: ", packet)
}
}
func sendRiakMetrics(conn *net.UDPConn, metrics *[]string) error {
data := []byte(strings.Join(*metrics, "\n"))
_, err := conn.Write(data)
if err != nil {
log.Println("Error sending metrics: %v", err)
}
return nil
}
func (c *TFTPServer) sendOptAck(conn *net.UDPConn, tid string, opts map[string]string) {
pkt := &tftp.TFTPOptionAckPkt{Opcode: tftp.OpcodeOptAck, Options: opts}
conn.SetWriteDeadline(time.Now().Add(1 * time.Second))
if _, err := conn.Write(pkt.Pack()); err != nil {
log.Errorln(err)
}
c.Connections[tid].OptACKSent()
}
func SendTest(i int, Conn *net.UDPConn) {
msg := strconv.Itoa(i)
buf := []byte(msg)
_, err := Conn.Write(buf)
if err != nil {
fmt.Println(msg, err)
}
}
//发送心跳包
func SendOnlineMessage(udpConn *net.UDPConn) {
for {
//每间隔1s向服务器发送一次在线信息
udpConn.Write([]byte(reflectString["在线"]))
sleepTimer := time.NewTimer(time.Second)
<-sleepTimer.C
}
}
// HandlePing - Receives a Ping message from server and sends a response
func (dht *DHTClient) HandlePing(data DHTMessage, conn *net.UDPConn) {
Log(Trace, "Ping message from DHT")
dht.LastDHTPing = time.Now()
msg := dht.Compose(DhtCmdPing, dht.ID, "", "")
_, err := conn.Write([]byte(msg))
if err != nil {
Log(Error, "Failed to send 'ping' packet: %v", err)
}
}
func UDPSend(conn *net.UDPConn, ch_transmit <-chan []byte) {
for {
msg := <-ch_transmit
_, err := conn.Write(msg)
if err != nil {
log.Printf("UDP write error: %s", err.Error())
}
}
}
func transmit(socket *net.UDPConn) {
for {
time.Sleep(2000 * time.Millisecond)
message := "From server: Hello I got your mesage"
socket.Write([]byte(message))
fmt.Println("Sendte: " + message)
}
}
func write_to_udp(socket *net.UDPConn) {
fmt.Println("Sender started")
time.Sleep(time.Millisecond * 1)
var p string
p = "Hei, server" + ("\x00")
arr := []byte(p)
socket.Write(arr)
}
func loggedWrite(socket *net.UDPConn, b []byte) {
n, err := socket.Write(b)
if err != nil {
log.Printf("sworm peer: write: %s", err)
}
if n != len(b) {
log.Printf("sworm peer: write: %d from %d", n, len(b))
}
}
func udpTest(Conn *net.UDPConn) bool {
buf := make([]byte, 1024)
Conn.SetReadDeadline(time.Now().Add(1 * time.Second))
Conn.Write([]byte("TEST"))
n, _, _ := Conn.ReadFromUDP(buf)
Conn.Close()
return string(buf[:n]) == "OK\n"
}
func di(udpConn *net.UDPConn, rAddr *net.UDPAddr, chap []byte, sn uint32, state State) (n int, err error) {
sendBytesBuffer := bytes.NewBuffer([]byte{})
binary.Write(sendBytesBuffer, binary.BigEndian, n)
len, _ := sendBytesBuffer.Write(chap)
if len != chapLen {
return 0, errChapPasswordForm
}
len, _ = sendBytesBuffer.Write(state.Bytes())
return udpConn.Write(sendBytesBuffer.Bytes())
}
func (clt *HopClient) toServer(u *net.UDPConn, flag byte, payload []byte, noise bool) {
hp := new(HopPacket)
hp.Flag = flag
hp.Seq = clt.Seq()
hp.setPayload(payload)
if noise {
hp.addNoise(mrand.Intn(MTU - 64 - len(payload)))
}
u.Write(hp.Pack())
}
// Broadcast message via UDP using Json
func UdpSender(parameter elevdriver.Button, con_udp *net.UDPConn) {
message, err := json.Marshal(parameter)
PrintError(err)
for {
time.Sleep(1000 * time.Millisecond)
_, err2 := con_udp.Write(message)
PrintError(err2)
}
}
func sendErrorWithoutLogging(udp_conn *net.UDPConn, addr *net.UDPAddr, code byte, emsg string) {
sendbuf := make([]byte, 5+len(emsg))
sendbuf[0] = 0
sendbuf[1] = 5 // 5 => opcode for ERROR
sendbuf[2] = 0
sendbuf[3] = code // error code
copy(sendbuf[4:], emsg)
sendbuf[len(sendbuf)-1] = 0 // 0-terminator
udp_conn.Write(sendbuf)
}
//发送消息
func SendMessage(udpConn *net.UDPConn) {
scaner := bufio.NewScanner(os.Stdin)
for scaner.Scan() {
if scaner.Text() == "exit" {
return
}
udpConn.Write([]byte(scaner.Text()))
}
}
/* Run the initial protocol with the TFTP server. */
func initialProtocol(conn *net.UDPConn, opcode []byte, filename string) (n int, resp []byte) {
resp = make([]byte, 516)
req := constructRequest(opcode, filename)
_, err := conn.Write(req)
checkError(err)
n, _, err = conn.ReadFromUDP(resp)
checkError(err)
return
}
func SendData(conn net.UDPConn, a string) int {
data := make([]byte, 4096)
data = []byte(a)
n, err := conn.Write(data)
if err != nil {
fmt.Println("Error writing to connection: (UDP)", err.Error())
return -1
}
return n
}
func WriteThing(conn *net.UDPConn) {
for {
data := []byte("Testing 123")
sent_bytes, err := conn.Write(data)
if err != nil {
log.Fatal(err)
}
log.Println("Sent", sent_bytes, "bytes")
time.Sleep(1 * time.Second)
}
}