func (e *Engine) connect(addr *net.TCPAddr) (*network.Device, error) {
conn, err := net.DialTCP("tcp", nil, addr)
if err != nil {
return nil, err
}
log.Println("New outgoing TCP connection")
return network.NewDevice(conn), nil
}
func (e *Engine) broadcastIdentity() error {
conn, err := net.Dial("udp", "255.255.255.255:"+strconv.Itoa(e.config.UdpPort))
if err != nil {
return err
}
device := network.NewDevice(conn)
err = e.sendIdentity(device)
if err != nil {
return err
}
conn.Close()
return nil
}
func (e *Engine) Listen() {
go e.udpServer.Listen()
go e.tcpServer.Listen()
go e.broadcastIdentity()
for {
select {
case udpPkg := <-e.udpServer.Incoming:
raddr := udpPkg.RemoteAddress
pkg := udpPkg.Package
if pkg.Type == protocol.IdentityType {
identity := pkg.Body.(*protocol.Identity)
if identity.DeviceId == e.config.DeviceId {
// Do not try to connect with ourselves
continue
}
if _, ok := e.devices[identity.DeviceId]; ok {
// Device already known
continue
}
log.Println("New device discovered by UDP:", identity)
device, err := e.connect(&net.TCPAddr{
IP: raddr.IP,
Port: identity.TcpPort,
Zone: raddr.Zone,
})
if err != nil {
log.Println("Could not open a TCP connection:", err)
continue
}
setDeviceIdentity(device, identity)
go e.handleDevice(device)
} else {
log.Println("Received a non-identity package on UDP connection", pkg)
}
case client := <-e.tcpServer.Joins:
log.Println("New incoming TCP connection")
device := network.NewDevice(client.Conn)
go e.handleDevice(device)
}
}
}