/// <summary>
/// Begins an asynchronous request to shut the connection down.
/// </summary>
/// <param name="callback">The <see cref="AsyncCallback"/> delegate.</param>
/// <param name="state">An object containing state information for this request.</param>
/// <returns>An <see cref="IAsyncResult"/> that references the asynchronous shutdown.</returns>
/// <exception cref="InvalidOperationException"><see cref="BeginShutdown"/> has already been called.</exception>
// Thanks to Michael J. Moore and Stefan Bernbo for notifying us about a bug in this method.
public IAsyncResult BeginShutdown(AsyncCallback callback, object state) {
if (m_ShutdownResult != null)
throw new InvalidOperationException();
AsyncResult ar = new AsyncResult(callback, state, null);
m_ShutdownResult = ar;
if (!this.Connected) {
ar.Notify(null);
} else if (SecureProtocol == SecureProtocol.None) {
base.Shutdown(SocketShutdown.Both);
ar.Notify(null);
} else {
m_Controller.BeginShutdown(new AsyncCallback(this.OnShutdown), null);
}
return ar;
}
/// <summary>
/// Ends an asynchronous request to shut the connection down.
/// </summary>
/// <param name="asyncResult">An <see cref="IAsyncResult"/> that references the asynchronous shutdown.</param>
/// <exception cref="ArgumentNullException"><paramref name="asyncResult"/> is a null reference (<b>Nothing</b> in Visual Basic).</exception>
/// <exception cref="InvalidOperationException"><see cref="BeginShutdown"/> has not been called first.</exception>
/// <exception cref="ArgumentException"><paramref name="asyncResult"/> has not been returned by a call to <see cref="BeginShutdown"/>.</exception>
public void EndShutdown(IAsyncResult asyncResult)
{
if (asyncResult == null)
throw new ArgumentNullException();
if (m_ShutdownResult == null)
throw new InvalidOperationException();
if (asyncResult != m_ShutdownResult)
throw new ArgumentException();
// Process the EndSecureShutdown
// block if the operation hasn't ended yet
AsyncResult ar = m_ShutdownResult;
while (!ar.IsCompleted)
{
ar.AsyncWaitHandle.WaitOne(200, false);
}
m_ShutdownResult = null;
//if (ar.AsyncException != null) // eat exceptions; they're not really important
// throw ar.AsyncException;
}
/// <summary>
/// Begins an asynchronous request for a connection to a network device.
/// </summary>
/// <param name="remoteEP">An <see cref="EndPoint"/> that represents the remote device.</param>
/// <param name="callback">The <see cref="AsyncCallback"/> delegate.</param>
/// <param name="state">An object that contains state information for this request.</param>
/// <returns>An <see cref="IAsyncResult"/> that references the asynchronous connection.</returns>
/// <exception cref="ArgumentNullException"><paramref name="remoteEP"/> is a null reference (<b>Nothing</b> in Visual Basic).</exception>
/// <exception cref="SocketException">An operating system error occurs while creating the SecureSocket.</exception>
/// <exception cref="ObjectDisposedException">The SecureSocket has been closed.</exception>
public override IAsyncResult BeginConnect(EndPoint remoteEP, AsyncCallback callback, object state) {
if (SecureProtocol == SecureProtocol.None)
return base.BeginConnect(remoteEP, callback, state);
// secure BeginConnect
if (remoteEP == null)
throw new ArgumentNullException();
if (m_ConnectResult != null)
throw new SocketException(); // BeginConnect already called
AsyncResult ret = new AsyncResult(callback, state, null);
m_ConnectResult = ret;
base.BeginConnect(remoteEP, new AsyncCallback(OnConnect), null);
return ret;
}
/// <summary>
/// Ends a pending asynchronous connection request.
/// </summary>
/// <param name="asyncResult">The result of the asynchronous operation.</param>
/// <exception cref="ArgumentNullException"><paramref name="asyncResult"/> is a null reference (<b>Nothing</b> in Visual Basic).</exception>
/// <exception cref="ArgumentException"><paramref name="asyncResult"/> was not returned by a call to the <see cref="BeginConnect"/> method.</exception>
/// <exception cref="InvalidOperationException"><see cref="EndConnect"/> was previously called for the asynchronous connection.</exception>
/// <exception cref="SocketException">An operating system error occurs while accessing the SecureSocket.</exception>
/// <exception cref="ObjectDisposedException">The SecureSocket has been closed.</exception>
/// <exception cref="SecurityException">An error occurred while negotiating the security protocol.</exception>
public override void EndConnect(IAsyncResult asyncResult)
{
if (SecureProtocol == SecureProtocol.None)
{
base.EndConnect(asyncResult);
return;
}
// Make sure everything is in order
if (asyncResult == null)
throw new ArgumentNullException();
if (m_ConnectResult == null)
throw new InvalidOperationException();
if (asyncResult != m_ConnectResult)
throw new ArgumentException();
// Process the (secure) EndConnect
// block if the operation hasn't ended yet
AsyncResult ar = m_ConnectResult;
while (!ar.IsCompleted)
{
ar.AsyncWaitHandle.WaitOne(200, false);
}
m_ConnectResult = null;
if (ar.AsyncException != null)
throw ar.AsyncException;
}