// Apparently binding to the same ports on UDPSender and UDPListener causes problems in unicast.
// Sharing the socket though, allows us to tunnel through firewalls as data is sent and received
// on the same endpoint.
// This region of code enables sharing sockets between the two classes.
internal static SockInterfacePair GetSharedSocket(IPEndPoint endPoint)
{
lock(socks)
{
object sockObj = socks[endPoint];
if( sockObj != null )
{
SockInterfacePair sip = (SockInterfacePair)sockObj;
++sip.sock.refCount;
return sip;
}
else
{
// Create the socket
LstSocks.Socket sock = new LstSocks.Socket(endPoint.AddressFamily, SocketType.Dgram, ProtocolType.Udp);
// Get the External Interface, save it for future use
IPAddress externalInterface = Utility.GetLocalRoutingInterface(endPoint.Address);
if (externalInterface == null)
{
// Pri3: Do something more helpful here
throw new Exception("Unable to find a local routing interface, is no network present?");
}
if( Utility.IsMulticast(endPoint.Address) )
{
// Allow multiple binds to this socket, as it will still function properly
// (this is only the case if it is a multicast socket. Unicast sockets fail to
// receive all data on all sockets)
sock.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, -1);
// We don't join the multicast group here, because we may not want to listen
// to our own data (halfing our throughput). jasonv - 10/28/2004
}
// Add the socket to the hashtable
SockInterfacePair sip = new SockInterfacePair();
sip.sock = sock;
sip.extInterface = externalInterface;
socks.Add(endPoint, sip);
// Increase the socket's reference count
++sock.refCount;
return sip;
}
}
}
// Apparently binding to the same ports on UDPSender and UDPListener causes problems in unicast.
// Sharing the socket though, allows us to tunnel through firewalls as data is sent and received
// on the same endpoint.
// This region of code enables sharing sockets between the two classes.
internal static SockInterfacePair GetSharedSocket(IPEndPoint endPoint)
{
lock (socks)
{
object sockObj = socks[endPoint];
if (sockObj != null)
{
SockInterfacePair sip = (SockInterfacePair)sockObj;
++sip.sock.refCount;
return(sip);
}
else
{
// Create the socket
LstSocks.Socket sock = new LstSocks.Socket(endPoint.AddressFamily, SocketType.Dgram, ProtocolType.Udp);
// Get the External Interface, save it for future use
IPAddress externalInterface = Utility.GetLocalRoutingInterface(endPoint.Address);
if (externalInterface == null)
{
// Pri3: Do something more helpful here
throw new Exception("Unable to find a local routing interface, is no network present?");
}
if (Utility.IsMulticast(endPoint.Address))
{
// Allow multiple binds to this socket, as it will still function properly
// (this is only the case if it is a multicast socket. Unicast sockets fail to
// receive all data on all sockets)
sock.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, -1);
// We don't join the multicast group here, because we may not want to listen
// to our own data (halfing our throughput). jasonv - 10/28/2004
}
// Add the socket to the hashtable
SockInterfacePair sip = new SockInterfacePair();
sip.sock = sock;
sip.extInterface = externalInterface;
socks.Add(endPoint, sip);
// Increase the socket's reference count
++sock.refCount;
return(sip);
}
}
}
internal static void ReleaseSharedSocket(IPEndPoint endPoint, LstSocks.Socket sock)
{
object sockObj = socks[endPoint];
if (sockObj == null)
{
throw new InvalidOperationException("Sock does not exist as a shared socket.");
}
lock (socks)
{
if (--sock.refCount <= 0)
{
// Leave the multicast group
if (Utility.IsMulticast(endPoint.Address))
{
try
{
if (endPoint.AddressFamily == AddressFamily.InterNetworkV6)
{
IPv6MulticastOption mo = new IPv6MulticastOption(endPoint.Address);
sock.SetSocketOption(SocketOptionLevel.IPv6, SocketOptionName.DropMembership, mo);
}
else
{
MulticastOption mo = new MulticastOption(endPoint.Address);
sock.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.DropMembership, mo);
}
}
catch {} // The user of the socket *may* not have joined the multicast group (?)
}
// Remove ourselves from the shared pool
socks.Remove(endPoint);
// Close the socket
try
{
sock.Close();
}
catch (ObjectDisposedException) {}
}
}
}
