lib/csharp/src/Transport/TSocket.cs

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 *
 * Contains some contributions under the Thrift Software License.
 * Please see doc/old-thrift-license.txt in the Thrift distribution for
 * details.
 */

using System;
using System.Net.Sockets;

namespace Thrift.Transport
{
	public class TSocket : TStreamTransport
	{
		private TcpClient client = null;
		private string host = null;
		private int port = 0;
		private int timeout = 0;

		public TSocket(TcpClient client)
		{
			this.client = client;

			if (IsOpen)
			{
				inputStream = client.GetStream();
				outputStream = client.GetStream();
			}
		}

		public TSocket(string host, int port) 
		    : this(host, port, 0)
		{
		}

		public TSocket(string host, int port, int timeout)
		{
			this.host = host;
			this.port = port;
			this.timeout = timeout;

			InitSocket();
		}

		private void InitSocket()
		{
			client = new TcpClient();
			client.ReceiveTimeout = client.SendTimeout = timeout;
			client.Client.NoDelay = true;
		}

		public int Timeout
		{
			set
			{
				client.ReceiveTimeout = client.SendTimeout = timeout = value;
			}
		}

		public TcpClient TcpClient
		{
			get
			{
				return client;
			}
		}

		public string Host
		{
			get
			{
				return host;
			}
		}

		public int Port
		{
			get
			{
				return port;
			}
		}

		public override bool IsOpen
		{
			get
			{
				if (client == null)
				{
					return false;
				}

				return client.Connected;
			}
		}

		public override void Open()
		{
			if (IsOpen)
			{
				throw new TTransportException(TTransportException.ExceptionType.AlreadyOpen, "Socket already connected");
			}

			if (String.IsNullOrEmpty(host))
			{
				throw new TTransportException(TTransportException.ExceptionType.NotOpen, "Cannot open null host");
			}

			if (port <= 0)
			{
				throw new TTransportException(TTransportException.ExceptionType.NotOpen, "Cannot open without port");
			}

			if (client == null)
			{
				InitSocket();
			}

			if( timeout == 0)			// no timeout -> infinite
			{
				client.Connect(host, port);
			}
			else                        // we have a timeout -> use it
			{
                ConnectHelper hlp = new ConnectHelper(client);
                IAsyncResult asyncres = client.BeginConnect(host, port, new AsyncCallback(ConnectCallback), hlp);
                bool bConnected = asyncres.AsyncWaitHandle.WaitOne(timeout) && client.Connected;
                if (!bConnected)
                {
                    lock (hlp.Mutex)
                    {
                        if( hlp.CallbackDone)
                        {
                            asyncres.AsyncWaitHandle.Close();
                            client.Close();
                        }
                        else
                        {
                            hlp.DoCleanup = true;
                            client = null;
                        }
                    }
                    throw new TTransportException(TTransportException.ExceptionType.TimedOut, "Connect timed out");
                }
			}

			inputStream = client.GetStream();
			outputStream = client.GetStream();
		}


        static void ConnectCallback(IAsyncResult asyncres)
        {
            ConnectHelper hlp = asyncres.AsyncState as ConnectHelper;
            lock (hlp.Mutex)
            {
                hlp.CallbackDone = true;
                    
                try
                {
                    if( hlp.Client.Client != null)
                        hlp.Client.EndConnect(asyncres);
                }
                catch (SocketException)
                {
                    // catch that away
                }

                if (hlp.DoCleanup) 
                {
                    asyncres.AsyncWaitHandle.Close();
                    if (hlp.Client is IDisposable)
                        ((IDisposable)hlp.Client).Dispose();
                    hlp.Client = null;
                }
            }
        }

        private class ConnectHelper
        {
            public object Mutex = new object();
            public bool DoCleanup = false;
            public bool CallbackDone = false;
            public TcpClient Client;
            public ConnectHelper(TcpClient client)
            {
                Client = client;
            }
        }

		public override void Close()
		{
			base.Close();
			if (client != null)
			{
				client.Close();
				client = null;
			}
		}

    #region " IDisposable Support "
    private bool _IsDisposed;

    // IDisposable
    protected override void Dispose(bool disposing)
    {
      if (!_IsDisposed)
      {
        if (disposing)
        {
          if (client != null)
            ((IDisposable)client).Dispose();
          base.Dispose(disposing);
        }
      }
      _IsDisposed = true;
    }
    #endregion
  }
}