public void InjectSelf()
{
_Original = this.InjectFunctionPointer<SendToDelegate>(AddressHelper.CodeOffset("gso", 0x1C274), 24);
}
public LocalMulticast(int port, Action <TMessage> handler = null, string name = null)
{
_handler = handler;
_name = name ?? String.Empty;
var msgSize = TypeHelper <TMessage> .FixedSize;
if (msgSize <= 0)
{
throw new ArgumentException($"Type {typeof(TMessage).Name} must be a blittable struct");
}
_bufferLength = msgSize;
_sendArgsPool = new ObjectPool <SocketAsyncEventArgs>(SendArgsFactory, 4);
var multicastAddress = IPAddress.Parse("239.199.99.9");
_mcEndPoint = new CachedEndPoint(new IPEndPoint(multicastAddress, port));
_inEndPoint = new CachedEndPoint(new IPEndPoint(IPAddress.Loopback, port));
_socket = new Socket(_inEndPoint.AddressFamily,
SocketType.Dgram, ProtocolType.Udp);
_socket.SetSocketOption(SocketOptionLevel.Socket,
SocketOptionName.ReuseAddress,
true);
_socket.SetSocketOption(SocketOptionLevel.Udp,
SocketOptionName.NoChecksum,
1);
_socket.SetSocketOption(SocketOptionLevel.IP,
SocketOptionName.MulticastTimeToLive,
2);
_socket.ExclusiveAddressUse = false;
_socket.Blocking = true;
_socket.EnableBroadcast = true;
// Maybe a fluke, bit perf drops and definitely not improves with this: _socket.UseOnlyOverlappedIO = true;
_socket.Bind(_inEndPoint);
// If you are using a connectionless protocol such as UDP,
// you do not have to call Connect before sending and
// receiving data. You can use SendTo and ReceiveFrom to
// synchronously communicate with a remote host.
// If you do call Connect, any datagrams that arrive from
// an address other than the specified default will be discarded.
// _socket.Connect(_mcEndPoint);
_socket.SetSocketOption(SocketOptionLevel.IP,
SocketOptionName.MulticastLoopback,
true);
// join on loopback interface
var mcastOption = new MulticastOption(multicastAddress, NetworkInterface.LoopbackInterfaceIndex);
_socket.SetSocketOption(SocketOptionLevel.IP,
SocketOptionName.AddMembership,
mcastOption);
_socket.SetSocketOption(SocketOptionLevel.IP,
SocketOptionName.MulticastInterface,
#pragma warning disable 618
(int)IPAddress.Loopback.Address);
#pragma warning restore 618
// see https://github.com/dotnet/corefx/issues/25699 if there are issues on non-Windows
// IPAddress.HostToNetworkOrder(NetworkInterface.LoopbackInterfaceIndex));
// Another option to limit source to loopback
//byte[] membershipAddresses = new byte[12]; // 3 IPs * 4 bytes (IPv4)
//Buffer.BlockCopy(multicastAddress.GetAddressBytes(), 0, membershipAddresses, 0, 4);
//Buffer.BlockCopy(IPAddress.Loopback.GetAddressBytes(), 0, membershipAddresses, 4, 4);
//Buffer.BlockCopy(IPAddress.Loopback.GetAddressBytes(), 0, membershipAddresses, 8, 4);
//_socket.SetSocketOption(SocketOptionLevel.IP,
// SocketOptionName.AddSourceMembership,
// membershipAddresses);
StartReceive();
#if NETCOREAPP3_0
try
{
_handle = _socket.SafeHandle;
var address = _mcEndPoint.Serialize();
_mcAddressSize = address.Size;
_mcAddressBuffer = new byte[_mcAddressSize];
for (int i = 0; i < _mcAddressSize; i++)
{
_mcAddressBuffer[i] = address[i];
}
var assembly = typeof(Socket).Assembly;
var socketPalType = assembly.GetTypes().FirstOrDefault(x => x.Name == "SocketPal");
var method = socketPalType?.GetMethods(BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Public)
.FirstOrDefault(m => m.Name == "SendTo");
_sendToDelegate = Delegate.CreateDelegate(typeof(SendToDelegate), method) as SendToDelegate;
}
catch
{
Trace.TraceInformation("Cannot get SocketPal.SendTo method");
}
#endif
}