/// <summary>
/// Handles the deserialization of the <see cref="Query" /> and <see cref="Response" />
/// messages from the blob data.
/// </summary>
/// <param name="es">The enhanced stream holding the payload data.</param>
protected override void ReadFrom(EnhancedStream es)
{
// Let the base message class load the properties and the data blob.
base.ReadFrom(es);
// Now parse the query and (optional) response messages from the blob
es = new EnhancedBlockStream(base._Data);
try
{
query = Msg.Load(es);
if (es.Eof)
{
response = null;
}
else
{
response = Msg.Load(es);
}
}
finally
{
es.Close();
}
}
/// <summary>
/// Handles message packets received on the socket.
/// </summary>
/// <param name="ar">The async result.</param>
private void OnSocketReceive(IAsyncResult ar)
{
int cb;
Msg msg = null;
byte[] msgBuf;
int cbMsg;
IPEndPoint fromEP = NetworkBinding.Any;
using (TimedLock.Lock(router.SyncRoot))
{
if (!isOpen)
{
return;
}
try
{
cb = sock.EndReceiveFrom(ar, ref recvEP);
if (cb > 0)
{
msgBuf = router.DecryptFrame(recvBuf, cb, out cbMsg);
msg = Msg.Load(new EnhancedMemoryStream(msgBuf));
fromEP = (IPEndPoint)recvEP;
msg._SetFromChannel(new ChannelEP(transport, fromEP));
}
}
catch (MsgException)
{
// Ignore messages that can't be parsed
}
catch (Exception e)
{
SysLog.LogException(e);
}
// Initiate the receive of the next message
if (sock.IsOpen)
{
try
{
sock.BeginReceiveFrom(recvBuf, 0, recvBuf.Length, SocketFlags.None, ref recvEP, onSocketReceive, null);
}
catch (Exception e)
{
SysLog.LogException(e, "LillTek UDP message channel is no longer able to receive messages.");
}
}
}
if (msg != null)
{
msg._Trace(router, 2, "UDP: Recv", string.Format("From: {0}", fromEP));
msg._Trace(router, 0, "Receive", string.Empty);
router.OnReceive(this, msg);
}
}
/// <summary>
/// Generates a clone of this message instance, generating a new
/// <see cref="_MsgID" /> property if the original ID is
/// not empty.
/// </summary>
/// <returns>Returns a clone of the message.</returns>
/// <remarks>
/// <para>
/// This base method works by serializing and then deseralizing a new copy of
/// the message to a buffer and then generating a new <see cref="_MsgID" /> GUID. This
/// implementation will be relatively costly in terms of processor and
/// memory resources.
/// </para>
/// <para>
/// Derived messages can choose to override this and implement a shallow
/// clone instead, using the <see cref="CopyBaseFields" /> method. Note that
/// the <see cref="CopyBaseFields" /> method ensures that a new <see cref="_MsgID" />
/// property is regenerated if the original ID field is not empty.
/// </para>
/// </remarks>
public virtual Msg Clone()
{
var es = new EnhancedBlockStream(1024, 1024);
Msg clone;
Msg.Save(es, this);
es.Position = 0;
clone = Msg.Load(es);
if (this.msgID != Guid.Empty)
{
clone.msgID = Helper.NewGuid();
}
return(clone);
}
/// <summary>
/// Handles messages received from the UdpBroadcast client.
/// </summary>
/// <param name="sender">The UDP broadcast client.</param>
/// <param name="args">Event arguments.</param>
private void OnBroadcastReceive(object sender, UdpBroadcastEventArgs args)
{
Msg msg = null;
byte[] msgBuf;
int cbMsg;
int cb;
using (TimedLock.Lock(router.SyncRoot))
{
if (!isOpen)
{
return;
}
try
{
cb = args.Payload.Length;
if (cb > 0)
{
msgBuf = router.DecryptFrame(args.Payload, cb, out cbMsg);
msg = Msg.Load(new EnhancedMemoryStream(msgBuf));
msg._SetFromChannel(new ChannelEP(transport, new IPEndPoint(args.SourceAddress, 0)));
}
}
catch (MsgException)
{
// Ignore messages that can't be parsed
}
catch (Exception e)
{
SysLog.LogException(e);
}
}
if (msg != null)
{
msg._Trace(router, 2, "UDP: Broadcast Recv", string.Format("From: {0}", args.SourceAddress));
msg._Trace(router, 0, "Receive", string.Empty);
router.OnReceive(this, msg);
}
}
/// <summary>
/// Handles receive completions on the socket.
/// </summary>
/// <param name="ar">The async result.</param>
private void OnReceive(IAsyncResult ar)
{
int cbRecv;
try
{
using (TimedLock.Lock(router.SyncRoot))
{
if (sock == null || recvBuf == null)
{
return;
}
try
{
cbRecv = sock.EndReceive(ar);
}
catch (SocketException e2)
{
if (e2.SocketErrorCode == SocketError.ConnectionReset)
{
cbRecv = 0; // Treat connection resets as connection closure
}
else
{
throw;
}
}
if (cbRecv == 0)
{
sock.ShutdownAndClose();
return;
}
SetLastAccess();
recvPos += cbRecv;
if (recvPos < recvBuf.Length)
{
// Continue the reception
sock.BeginReceive(recvBuf, recvPos, recvBuf.Length - recvPos, SocketFlags.None, onReceive, null);
return;
}
if (recvHeader)
{
// Initiate reception of the frame payload
int pos = 0;
int cbFrame;
byte[] buf;
cbFrame = Helper.ReadInt32(recvBuf, ref pos);
buf = new byte[MsgRouter.FrameHeaderSize + cbFrame];
Array.Copy(recvBuf, 0, buf, 0, MsgRouter.FrameHeaderSize);
recvHeader = false;
recvBuf = buf;
recvPos = MsgRouter.FrameHeaderSize;
cbRecv = cbFrame;
sock.BeginReceive(recvBuf, recvPos, cbFrame, SocketFlags.None, onReceive, null);
}
else
{
// We've completed the reception of a message
Msg msg;
byte[] msgBuf;
int cbMsg;
msgBuf = router.DecryptFrame(recvBuf, recvBuf.Length, out cbMsg);
msg = Msg.Load(new EnhancedMemoryStream(msgBuf));
msgBuf = null;
// Handle initialization messages locally and queue a
// notification for all other messages so that router.OnReceive()
// will be called on a worker thread.
if (!initProcessed)
{
TcpInitMsg initMsg;
Exception e;
initMsg = msg as TcpInitMsg;
if (initMsg == null)
{
e = new MsgException("Invalid TCP channel protocol: TcpInitMsg expected.");
SysLog.LogException(e);
Helper.Rethrow(e);
}
initMsg._Trace(router, 2, "Receive", null);
// If the sender indicates that it is an uplink then we're going
// to use the actual remote port for the remoteEP rather than
// ListenPort (which should be 0). The reason for this is that
// intervening routers and NATs may translate the port number
// reported by the child router.
routerEP = initMsg.RouterEP;
remoteEP.NetEP.Port = initMsg.IsUplink ? ((IPEndPoint)sock.RemoteEndPoint).Port : initMsg.ListenPort;
isDownlink = initMsg.IsUplink;
isP2P = initMsg.RouterInfo.IsP2P;
initProcessed = true;
router.OnTcpInit(this);
}
else
{
msg._SetFromChannel(remoteEP);
msg._Trace(router, 2, "TCP: Recv", null);
msg._Trace(router, 0, "Receive", string.Empty);
router.OnReceive(this, msg);
}
// Initiate reception of the next message
BeginReceive();
}
}
}
catch (SocketException e)
{
// Don't log connection resets because we see these all the
// time when a router stops. We're not going to consider
// this to be an error.
if (e.SocketErrorCode != SocketError.ConnectionReset)
{
TraceException(e);
SysLog.LogException(e);
}
router.OnTcpClose(this);
Close();
}
catch (Exception e)
{
TraceException(e);
SysLog.LogException(e);
router.OnTcpClose(this);
Close();
}
}
