protected void ProcessUDTPacket(IUDTPacket p)
{
//(3).Check the packet type and process it according to this.
if (!p.IsControlPacket())
{
DataPacket dp = (DataPacket)p;
if (storeStatistics)
{
dataPacketInterval.End();
dataProcessTime.Begin();
}
OnDataPacketReceived(dp);
if (storeStatistics)
{
dataProcessTime.End();
dataPacketInterval.Begin();
}
}
else if (p.GetControlPacketType() == (int)ControlPacketType.ACK2)
{
Acknowledgment2 ack2 = (Acknowledgment2)p;
onAck2PacketReceived(ack2);
}
else if (p is Shutdown)
{
OnShutdown();
}
}
/// <summary>
/// 发送网络数据
/// </summary>
/// <param name="packet"></param>
internal void DoSend(IUDTPacket packet)
{
byte[] data = packet.GetEncoded();
var dgp = packet.GetSession().Datagram;
dgSocket.SendTo(data, dgp.Remote);
}
/*
* packets are written by the endpoint
*/
internal void Receive(IUDTPacket p)
{
if (storeStatistics)
{
dgReceiveInterval.End();
}
handoffQueue.Add(p);
if (storeStatistics)
{
dgReceiveInterval.Begin();
}
}
//receive a packet from server from the peer
internal void Receive(IUDTPacket p)
{
if (p is Acknowledgement)
{
Acknowledgement acknowledgement = (Acknowledgement)p;
OnAcknowledge(acknowledgement);
}
else if (p is NegativeAcknowledgement)
{
NegativeAcknowledgement nak = (NegativeAcknowledgement)p;
OnNAKPacketReceived(nak);
}
else if (p is KeepAlive)
{
session.Socket.GetReceiver().ResetEXPCount();
}
}
/**
* receiver algorithm
* see specification P11.
*/
public void ReceiverAlgorithm()
{
//check ACK timer
long currentTime = Util.getCurrentTime();
if (nextACK < currentTime)
{
nextACK = currentTime + ackTimerInterval;
ProcessACKEvent(true);
}
//check NAK timer
if (nextNAK < currentTime)
{
nextNAK = currentTime + nakTimerInterval;
ProcessNAKEvent();
}
//check EXP timer
if (nextEXP < currentTime)
{
nextEXP = currentTime + expTimerInterval;
ProcessEXPEvent();
}
//perform time-bounded UDP receive
IUDTPacket packet = null;
handoffQueue.TryTake(out packet, (int)Util.GetSYNTime());
if (packet != null)
{
//reset exp count to 1
expCount = 1;
//If there is no unacknowledged data packet, or if this is an
//ACK or NAK control packet, reset the EXP timer.
bool needEXPReset = false;
if (packet.IsControlPacket())
{
ControlPacket cp = (ControlPacket)packet;
int cpType = cp.GetControlPacketType();
if (cpType == (int)ControlPacketType.ACK || cpType == (int)ControlPacketType.NAK)
{
needEXPReset = true;
}
}
if (needEXPReset)
{
nextEXP = Util.getCurrentTime() + expTimerInterval;
}
if (storeStatistics)
{
processTime.Begin();
}
ProcessUDTPacket(packet);
if (storeStatistics)
{
processTime.End();
}
}
Thread.Yield();
}
public abstract void Received(IUDTPacket packet, Destination peer);
public int CompareTo(IUDTPacket other)
{
return((int)(GetPacketSequenceNumber() - other.GetPacketSequenceNumber()));
}
public override void Received(IUDTPacket packet, Destination peer)
{
lastPacket = packet;
if (packet is ConnectionHandshake)
{
ConnectionHandshake hs = (ConnectionHandshake)packet;
FlashLogger.Info("Received connection handshake from " + peer + "\n" + hs);
if (State != ready)
{
if (hs.ConnectionType == 1)
{
try {
//TODO validate parameters sent by peer
// long peerSocketID = hs.SocketID;
// DestinationID = peerSocketID;
// destination(peerSocketID);
destination.SocketID = hs.SocketID;
SendConfirmation(hs);
} catch (Exception ex) {
FlashLogger.Warn("Error creating socket", ex);
State = invalid;
}
return;
}
else
{
try {
//TODO validate parameters sent by peer
//理论上这里是getConnectionType==-1
// long peerSocketID = hs.getSocketID();
// destination.SetSocketID(peerSocketID);
// setState(ready);
destination.SocketID = hs.SocketID;
State = ready;
Thread.Sleep(50);
//多个握手序列，使用接收的第一个
this.initialSequenceNumber = hs.InitialSeqNo;//cd 必须重置
socket = new UDTSocket(endPoint, this);
} catch (Exception ex) {
FlashLogger.Warn("Error creating socket", ex);
State = invalid;
}
return;
}
}
}
if (State == ready)
{
if (packet is Shutdown)
{
State = shutdown;
active = false;
FlashLogger.Info("Connection shutdown initiated by the other side.");
return;
}
active = true;
try {
if (packet.ForSender())
{
socket.GetSender().Receive(lastPacket);
}
else
{
socket.GetReceiver().Receive(lastPacket);
}
} catch (Exception ex) {
//session is invalid
FlashLogger.Error("Error in " + toString(), ex);
//setState(invalid);
State = invalid;
}
return;
}
}
/**
* single receive, run in the receiverThread, see {@link #start()}
* <ul>
* <li>Receives UDP packets from the network</li>
* <li>Converts them to UDT packets</li>
* <li>dispatches the UDT packets according to their destination ID.</li>
* </ul>
* @throws IOException
*/
protected void DoReceive()
{
EndPoint remotePoint = new IPEndPoint(IPAddress.Any, 0);
while (!stopped)
{
try
{
try
{
//v.end();
//will block until a packet is received or timeout has expired
int len = dgSocket.ReceiveFrom(dp, ref remotePoint);
//v.begin();
Destination peer = new Destination(remotePoint);
IUDTPacket packet = PacketFactory.CreatePacket(dp, len);
lastPacket = packet;
//handle connection handshake
if (packet.IsConnectionHandshake())
{
lock (lock_obj)
{
long id = packet.DestinationID;
UDTSession session = null;
sessions.TryGetValue(id, out session);
if (session == null)
{
session = new ServerSession((IPEndPoint)remotePoint, this);
AddSession(session.SocketID, session);
//TODO need to check peer to avoid duplicate server session
if (serverSocketMode)
{
FlashLogger.Info("Pooling new request.");
sessionHandoff.Add(session);
FlashLogger.Info("Request taken for processing.");
}
}
peer.SocketID = ((ConnectionHandshake)packet).SocketID;
session.Received(packet, peer);
}
}
else
{
//dispatch to existing session
long dest = packet.DestinationID;
UDTSession session;
if (dest == lastDestID)
{
session = lastSession;
}
else
{
// session =
sessions.TryGetValue(dest, out session);//cd 获取session
lastSession = session;
lastDestID = dest;
}
if (session == null)
{
n++;
if (n % 100 == 1)
{
FlashLogger.Warn("Unknown session <" + dest + "> requested from <" + peer + "> packet type " + packet);
}
}
else
{
Console.WriteLine("收到包");
session.Received(packet, peer);
}
}
}
catch (SocketException ex)
{
if (ex.Message.Equals("socket closed") && stopped)
{
//cd
//已经正常关闭
}
else
{
FlashLogger.Info("SocketException: " + ex.Message);
}
}
catch (Exception ste)
{
//can safely ignore... we will retry until the endpoint is stopped
}
}
catch (Exception ex)
{
FlashLogger.Warn("Got: " + ex.Message, ex);
}
}
}
public override void Received(IUDTPacket packet, Destination peer)
{
lastPacket = packet;
if (packet is ConnectionHandshake)
{
ConnectionHandshake connectionHandshake = (ConnectionHandshake)packet;
FlashLogger.Info("Received " + connectionHandshake);
if (State <= ready)
{
destination.SocketID = connectionHandshake.SocketID;
if (State <= handshaking)
{
State = handshaking;
}
try {
HandleHandShake(connectionHandshake);
n_handshake++;
try {
//理论上应该先检验cookie
State = ready;
socket = new UDTSocket(endPoint, this);
cc.Init();
} catch (Exception uhe) {
//session is invalid
FlashLogger.Error("", uhe);
State = invalid;
}
} catch (IOException ex) {
//session invalid
FlashLogger.Warn("Error processing ConnectionHandshake", ex);
State = invalid;
}
return;
}
else
{
//cd 回复
try {
HandleHandShake(connectionHandshake);
} catch (IOException e) {
}
}
}
else if (packet is KeepAlive)
{
socket.GetReceiver().ResetEXPTimer();
active = true;
return;
}
if (State == ready)
{
active = true;
if (packet is KeepAlive)
{
//nothing to do here
return;
}
else if (packet is Shutdown)
{
try {
socket.GetReceiver().Stop();
} catch (IOException ex) {
FlashLogger.Warn("", ex);
}
State = shutdown;
Console.WriteLine("SHUTDOWN ***");
active = false;
FlashLogger.Info("Connection shutdown initiated by the other side.");
return;
}
else
{
try {
Console.WriteLine("收到数据包");
if (packet.ForSender())
{
socket.GetSender().Receive(packet);
}
else
{
socket.GetReceiver().Receive(packet);
}
} catch (Exception ex) {
//session invalid
FlashLogger.Error("", ex);
State = invalid;
// setState(invalid);
}
}
return;
}
}
