Пример #1
0
// raw packet encapsulation and put it online
func (buf *Buffer) raw_send(data []byte) bool {
	// combine output to reduce syscall.write
	sz := len(data)
	binary.BigEndian.PutUint16(buf.cache, uint16(sz))
	copy(buf.cache[2:], data)

	// write data
	n, err := buf.conn.Write(buf.cache[:sz+2])
	if err != nil {
		log.Warningf("Error send reply data, bytes: %v reason: %v", n, err)
		return false
	}

	return true
}
Пример #2
0
// add a service
func (p *service_pool) add_service(key, value string) {
	p.Lock()
	defer p.Unlock()
	service_name := filepath.Dir(key)
	// name check
	if p.enable_name_check && !p.service_names[service_name] {
		log.Warningf("service not in names: %v, ignored", service_name)
		return
	}

	if p.services[service_name] == nil {
		p.services[service_name] = &service{}
		log.Tracef("new service type: %v", service_name)
	}
	service := p.services[service_name]

	if conn, err := grpc.Dial(value, grpc.WithTimeout(DEFAULT_DIAL_TIMEOUT), grpc.WithInsecure()); err == nil {
		service.clients = append(service.clients, client{key, conn})
		log.Tracef("service added: %v -- %v", key, value)
	} else {
		log.Errorf("did not connect: %v -- %v err: %v", key, value, err)
	}
}
Пример #3
0
// start a goroutine when a new connection is accepted
func handleClient(conn *net.TCPConn) {
	defer utils.PrintPanicStack()
	// set per-connection socket buffer
	conn.SetReadBuffer(SO_RCVBUF)

	// set initial socket buffer
	conn.SetWriteBuffer(SO_SNDBUF)

	// initial network control struct
	header := make([]byte, 2)
	in := make(chan []byte)
	defer func() {
		close(in) // session will close
	}()

	// create a new session object for the connection
	var sess Session
	host, port, err := net.SplitHostPort(conn.RemoteAddr().String())
	if err != nil {
		log.Error("cannot get remote address:", err)
		return
	}
	sess.IP = net.ParseIP(host)
	log.Infof("new connection from:%v port:%v", host, port)

	// session die signal
	sess.Die = make(chan struct{})

	// create a write buffer
	out := new_buffer(conn, sess.Die)
	go out.start()

	// start one agent for handling packet
	wg.Add(1)
	go agent(&sess, in, out)

	// network loop
	for {
		// solve dead link problem
		conn.SetReadDeadline(time.Now().Add(TCP_READ_DEADLINE * time.Second))
		n, err := io.ReadFull(conn, header)
		if err != nil {
			log.Warningf("read header failed, ip:%v reason:%v size:%v", sess.IP, err, n)
			return
		}
		size := binary.BigEndian.Uint16(header)

		// alloc a byte slice for reading
		payload := make([]byte, size)
		// read msg
		n, err = io.ReadFull(conn, payload)
		if err != nil {
			log.Warningf("read payload failed, ip:%v reason:%v size:%v", sess.IP, err, n)
			return
		}

		select {
		case in <- payload: // payload queued
		case <-sess.Die:
			log.Warningf("connection closed by logic, flag:%v ip:%v", sess.Flag, sess.IP)
			return
		}
	}
}
Пример #4
0
// PIPELINE #1: handleClient
// the goroutine is used for reading incoming PACKETS
// each packet is defined as :
// | 2B size |     DATA       |
//
func handleClient(conn *net.TCPConn) {
	defer utils.PrintPanicStack()
	// set socket read buffer
	conn.SetReadBuffer(SO_RCVBUF)
	// set socket write buffer
	conn.SetWriteBuffer(SO_SNDBUF)

	// for reading the 2-Byte header
	header := make([]byte, 2)
	// the input channel for agent()
	in := make(chan []byte)
	defer func() {
		close(in) // session will close
	}()

	// create a new session object for the connection
	// and record it's IP address
	var sess Session
	host, port, err := net.SplitHostPort(conn.RemoteAddr().String())
	if err != nil {
		log.Error("cannot get remote address:", err)
		return
	}
	sess.IP = net.ParseIP(host)
	log.Infof("new connection from:%v port:%v", host, port)

	// session die signal, will be triggered by agent()
	sess.Die = make(chan struct{})

	// create a write buffer
	out := new_buffer(conn, sess.Die)
	go out.start()

	// start agent for PACKET processing
	wg.Add(1)
	go agent(&sess, in, out)

	// read loop
	for {
		// solve dead link problem:
		// physical disconnection without any communcation between client and server
		// will cause the read to block FOREVER, so a timeout is a rescue.
		conn.SetReadDeadline(time.Now().Add(TCP_READ_DEADLINE * time.Second))

		// read 2B header
		n, err := io.ReadFull(conn, header)
		if err != nil {
			log.Warningf("read header failed, ip:%v reason:%v size:%v", sess.IP, err, n)
			return
		}
		size := binary.BigEndian.Uint16(header)

		// alloc a byte slice of the size defined in the header for reading data
		payload := make([]byte, size)
		n, err = io.ReadFull(conn, payload)
		if err != nil {
			log.Warningf("read payload failed, ip:%v reason:%v size:%v", sess.IP, err, n)
			return
		}

		// deliver the data to the input queue of agent()
		select {
		case in <- payload: // payload queued
		case <-sess.Die:
			log.Warningf("connection closed by logic, flag:%v ip:%v", sess.Flag, sess.IP)
			return
		}
	}
}