/source/library/Interlace/ReactorCore/DatagramSocketConnection.cs

#region Using Directives and Copyright Notice



// Copyright (c) 2007-2010, Computer Consultancy Pty Ltd

// All rights reserved.

// 

// Redistribution and use in source and binary forms, with or without

// modification, are permitted provided that the following conditions are met:

//     * Redistributions of source code must retain the above copyright

//       notice, this list of conditions and the following disclaimer.

//     * Redistributions in binary form must reproduce the above copyright

//       notice, this list of conditions and the following disclaimer in the

//       documentation and/or other materials provided with the distribution.

//     * Neither the name of the Computer Consultancy Pty Ltd nor the

//       names of its contributors may be used to endorse or promote products

//       derived from this software without specific prior written permission.

// 

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 

// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 

// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 

// ARE DISCLAIMED. IN NO EVENT SHALL COMPUTER CONSULTANCY PTY LTD BE LIABLE 

// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 

// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 

// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 

// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 

// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 

// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH

// DAMAGE.



using System;

using System.Collections.Generic;

using System.Net;

using System.Net.Sockets;

using System.Text;



#endregion



namespace Interlace.ReactorCore

{

    public class DatagramSocketConnection : SocketConnection

    {

        EndPoint _receiveEndpoint;

        bool _truncationOccurred = false;



        public DatagramSocketConnection(IReactor reactor, Protocol protocol)

        : base(reactor, protocol)

        {

        }



        public bool TruncationOccurred

        { 	 

           get { return _truncationOccurred; }

        }



        bool IsTemporaryError(SocketError error)

        {

            switch (error)

            {

                case SocketError.ConnectionReset:

                case SocketError.ConnectionRefused:

                    return true;



                default:

                    return false;

            }

        }



        protected override void ContinueReceive()

        {

            IAsyncResult result;



            try

            {

                _receiveEndpoint = new IPEndPoint(IPAddress.Any, 0);



                result = _socket.BeginReceiveFrom(_receiveBuffer, 0,

                    _receiveBuffer.Length, SocketFlags.None, ref _receiveEndpoint, null, null);

            }

            catch (SocketException ex)

            {

                // Some errors (for instance, the error from sending to a closed 

                // port on localhost) should be ignored:

                if (IsTemporaryError(ex.SocketErrorCode))

                {

                    ContinueReceive();



                    return;

                }



                HandleSocketException(ex);



                return;

            }

            catch (ObjectDisposedException ex)

            {

                HandleSocketClosed(ex);



                return;

            }



            _reactor.AddResult(result, ReceiveCompleted);

        }



        void ReceiveCompleted(IAsyncResult result, object state)

        {

            int bytesReceived;



            try

            {

                bytesReceived = _socket.EndReceiveFrom(result, ref _receiveEndpoint);

            }

            catch (SocketException ex)

            {

                // Some errors (for instance, the error from sending to a closed 

                // port on localhost) should be ignored:

                if (IsTemporaryError(ex.SocketErrorCode))

                {

                    ContinueReceive();



                    return;

                }



                HandleSocketException(ex);



                return;

            }

            catch (ObjectDisposedException ex)

            {

                HandleSocketClosed(ex);



                return;

            }



            try

            {

                _protocol.DataReceived(_receiveEndpoint as IPEndPoint, _receiveBuffer, 0, bytesReceived);

                _receiveEndpoint = null;

            }

            catch (Exception ex)

            {

                HandleProtocolException(ex);

            }



            ContinueReceive();

        }



        protected override void ContinueSend()

        {

            IAsyncResult result;



            try

            {

                if (_transmitBuffer.EndPointOrNull == null)

                {

                    result = _socket.BeginSend(_transmitBuffer.Data.Array, _transmitBuffer.Data.Offset,

                        _transmitBuffer.Data.Count, SocketFlags.None, null, null);

                }

                else

                {

                    result = _socket.BeginSendTo(_transmitBuffer.Data.Array, _transmitBuffer.Data.Offset,

                        _transmitBuffer.Data.Count, SocketFlags.None, _transmitBuffer.EndPointOrNull, null, null);

                }

            }

            catch (SocketException ex)

            {

                HandleSocketException(ex);



                return;

            }

            catch (ObjectDisposedException ex)

            {

                HandleSocketClosed(ex);



                return;

            }



            _reactor.AddResult(result, SendCompleted);

        }



        void SendCompleted(IAsyncResult result, object state)

        {

            int bytesSent;



            try

            {

                if (_transmitBuffer.EndPointOrNull == null)

                {

                    bytesSent = _socket.EndSend(result);

                }

                else

                {

                    bytesSent = _socket.EndSendTo(result);

                }

            }

            catch (SocketException ex)

            {

                if (IsTemporaryError(ex.SocketErrorCode))

                {

                    _isTransmitting = false;



                    KickSendQueue();



                    return;

                }



                HandleSocketException(ex);



                return;

            }

            catch (ObjectDisposedException ex)

            {

                HandleSocketClosed(ex);



                return;

            }



            if (bytesSent != _transmitBuffer.Data.Count)

            {

                _truncationOccurred = true;



                return;

            }



            _isTransmitting = false;



            KickSendQueue();

        }

    }

}