/// <summary>
/// Resolves IP address. Throws the CanNotResolveHostName exception if resolving fails.
/// </summary>
/// <param name="url">Url to resolve.</param>
/// <returns>Resolved IPAddress.</returns>
public static IPAddress ResolveIPAddress(string url)
{
IPAddress ipAddress = null;
try
{
if (url.Length > 0 && url[0] >= '0' && url[0] <= '9')
{
ipAddress = IPAddress.Parse(url);
}
}
catch
{
}
if (ipAddress == null)
{
IPAddress[] addresses = Dns.GetHostEntry(url).AddressList;
if (addresses.Length <= 0)
{
throw GenuineExceptions.Get_Connect_CanNotResolveHostName(url);
}
ipAddress = addresses[0];
}
if (ipAddress == null)
{
throw GenuineExceptions.Get_Connect_CanNotResolveHostName(url);
}
return(ipAddress);
}
/// <summary>
/// Resolves the remote host IP address and establishes the connection.
/// </summary>
/// <param name="ignored">This parameter is ignored.</param>
private void StartConnecting(object ignored)
{
try
{
lock (this._syncRoot)
{
if (!this._continue)
{
return;
}
}
// resolve host name to IP address
IPAddress ipAddress = GenuineUtility.ResolveIPAddress(hostName);
if (ipAddress == null)
{
throw GenuineExceptions.Get_Connect_CanNotResolveHostName(hostName);
}
// get the address of the remote host
IPEndPoint ipEndPoint = new IPEndPoint(ipAddress, this._portNumber);
if (ipEndPoint == null)
{
throw GenuineExceptions.Get_Connect_CanNotConnectToRemoteHost(this.hostName, "The IPEndPoint instance cannot be created.");
}
// create and setup a socket
socket = new Socket(ipEndPoint.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
LingerOption lingerOption = new LingerOption(true, 3);
socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.Linger, lingerOption);
if ((bool)this._parameterProvider[GenuineParameter.TcpDisableNagling])
{
socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.NoDelay, 1);
}
int tcpReceiveBufferSize = (int)this._parameterProvider[GenuineParameter.TcpReceiveBufferSize];
int tcpSendBufferSize = (int)this._parameterProvider[GenuineParameter.TcpSendBufferSize];
if (tcpReceiveBufferSize >= 0)
{
socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReceiveBuffer, tcpReceiveBufferSize);
}
if (tcpSendBufferSize >= 0)
{
socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.SendBuffer, tcpSendBufferSize);
}
lock (this._syncRoot)
{
if (!this._continue)
{
return;
}
}
// connect to the remote host
socket.Connect(ipEndPoint);
this.Completed.Set();
}
catch (Exception ex)
{
this.CancelConnecting(ex);
}
}