ALFA.SystemInfo.GetServerUdpListener C# (CSharp) Метод

        public static IPEndPoint GetServerUdpListener(CLRScriptBase Script)
        {
            int CurrentProcessId = Process.GetCurrentProcess().Id;
            uint TableSize = 0;
            IntPtr Table = IntPtr.Zero;
            uint Status = NO_ERROR;
            int LocalPort;

            //
            // If we have cached the data, return it from the cache.
            //
            // It is important to check the cache if we spin up a secondary
            // UDP socket (and that the cache is first set before that is done)
            // or else we might return the wrong listener.
            //

            if ((LocalPort = Script.GetGlobalInt("ACR_SERVERLISTENER_PORT")) != 0)
            {
                return new IPEndPoint((long)(UInt32)Script.GetGlobalInt("ACR_SERVERLISTENER_ADDRESS"), LocalPort);
            }

            //
            // Find the first UDP listener owned by this process and assume
            // that it's the right one.
            //

            try
            {
                do
                {
                    if (Table != IntPtr.Zero)
                    {
                        Marshal.FreeHGlobal(Table);
                        Table = IntPtr.Zero;
                    }

                    if (TableSize != 0)
                    {
                        Table = Marshal.AllocHGlobal((int)TableSize);
                    }

                    Status = GetExtendedUdpTable(Table, ref TableSize, 1, AF_INET, UDP_TABLE_CLASS.UDP_TABLE_OWNER_PID, 0);
                } while (Status == ERROR_INSUFFICIENT_BUFFER);

                if (Status != NO_ERROR)
                {
                    throw new ApplicationException(String.Format("ALFA.SystemInfo.GetServerUdpListener: GetExtendedUdpTable failed, status = {0}", Status));
                }

                MIB_UDPTABLE_OWNER_PID UdpTable = (MIB_UDPTABLE_OWNER_PID) Marshal.PtrToStructure(Table, typeof(MIB_UDPTABLE_OWNER_PID));

                for (uint Row = 0; Row < UdpTable.dwNumEntries; Row += 1)
                {
                    IntPtr TableOffset = Marshal.OffsetOf(typeof(MIB_UDPTABLE_OWNER_PID), "table");
                    int RowSize = Marshal.SizeOf(typeof(MIB_UDPROW_OWNER_PID));
                    IntPtr RowOffset = IntPtr.Add(TableOffset, (int)(RowSize * Row));
                    MIB_UDPROW_OWNER_PID UdpRow = (MIB_UDPROW_OWNER_PID)Marshal.PtrToStructure(IntPtr.Add(Table, (int)RowOffset), typeof(MIB_UDPROW_OWNER_PID));

                    if (UdpRow.dwOwningPid != (uint)CurrentProcessId)
                        continue;

                    LocalPort = IPAddress.NetworkToHostOrder((short)UdpRow.dwLocalPort);

                    //
                    // Use loopback (disable deprecation warning) if we have no
                    // bound address.
                    //

#pragma warning disable 618
                    if (UdpRow.dwLocalAddr == 0)
                        UdpRow.dwLocalAddr = (uint)(ulong)IPAddress.Loopback.Address;
#pragma warning restore 618

                    //
                    // Cache the data and return a new endpoint object for the
                    // address.
                    //

                    Script.SetGlobalInt("ACR_SERVERLISTENER_PORT", LocalPort);
                    Script.SetGlobalInt("ACR_SERVERLISTENER_ADDRESS", (int)UdpRow.dwLocalAddr);

                    return new IPEndPoint((long)(ulong)UdpRow.dwLocalAddr, LocalPort);
                }
            }
            finally
            {
                if (Table != IntPtr.Zero)
                    Marshal.FreeHGlobal(Table);
            }

            throw new ApplicationException("Endpoint not found.");
        }