|
private static OnLowLevelReceive ( |
||
| s | Supplies the socket that received data. | |
| buf | Supplies the buffer pointer (length of len). /// | |
| len | int | Supplies the count of bytes received. |
| flags | int | Supplies the original recvfrom flags. |
| from | Supplies the sender address. This is known to /// be at least the size of a sockaddr_in. | |
| fromlen | Supplies the length of the sender address. /// | |
| return | int | |
private static int OnLowLevelReceive(IntPtr s, IntPtr buf, int len, int flags, IntPtr from, IntPtr fromlen)
{
if (RecvfromSocket == IntPtr.Zero)
RecvfromSocket = s;
if (LocalDataPort == 0)
{
try
{
sockaddr_in LocalSocketName;
int NameLen = Marshal.SizeOf(typeof(sockaddr_in));
if (getsockname(RecvfromSocket, out LocalSocketName, ref NameLen) == 0)
{
//
// Use loopback (disable deprecation warning) if we have no
// bound address.
//
#pragma warning disable 618
if (LocalSocketName.sin_addr == 0)
LocalSocketName.sin_addr = (uint)(ulong)IPAddress.Loopback.Address;
#pragma warning restore 618
LocalDataPort = (int)IPAddress.NetworkToHostOrder((short)LocalSocketName.sin_port);
LocalListenerAddress = (int)LocalSocketName.sin_addr;
}
}
catch
{
}
}
if (len < 5 || Marshal.ReadInt32(fromlen) < Marshal.SizeOf(typeof(sockaddr_in)))
return len;
if (Marshal.ReadInt32(buf) != ALFAProtocolMagic)
return len;
try
{
switch ((PROTOCOL_ID)Marshal.ReadByte(buf + 4))
{
case PROTOCOL_ID.PROTOCOL_DATAGRAM:
sockaddr_in Sender = (sockaddr_in)Marshal.PtrToStructure(from, typeof(sockaddr_in));
if (Sender.sin_family != AF_INET)
return len;
OnDatagramReceive(buf, len, Sender);
return 0;
default:
return 0;
}
}
catch
{
return 0;
}
}
