private bool SetAsyncEventSelect(AsyncEventBits blockEventBits)
{
GlobalLog.Enter("Socket#" + ValidationHelper.HashString(this) + "::SetAsyncEventSelect", "blockEventBits:" + blockEventBits.ToString() + " m_BlockEventBits:" + m_BlockEventBits.ToString() + " willBlockInternal:" + willBlockInternal.ToString());
GlobalLog.Assert(blockEventBits != AsyncEventBits.FdNone, "Socket#{0}::SetAsyncEventSelect|Use UnsetAsyncEventSelect for FdNone.", ValidationHelper.HashString(this));
GlobalLog.Assert(m_BlockEventBits == AsyncEventBits.FdNone || m_BlockEventBits == blockEventBits, "Socket#{0}::SetAsyncEventSelect|Can't change from one active wait to another.", ValidationHelper.HashString(this));
GlobalLog.Assert(m_RegisteredWait == null, "Socket#{0}::SetAsyncEventSelect|Already actively waiting on an op.", ValidationHelper.HashString(this));
// This check is bogus, too late diggin into a historical reason for it.
// Make sure the upper level will fail with ObjectDisposedException
if (m_RegisteredWait != null)
return false;
//
// This will put us into non-blocking mode. Create the event if it isn't, and register a wait.
//
if (m_AsyncEvent == null)
{
Interlocked.CompareExchange<ManualResetEvent>(ref m_AsyncEvent, new ManualResetEvent(false), null);
if (s_RegisteredWaitCallback == null)
s_RegisteredWaitCallback = new WaitOrTimerCallback(RegisteredWaitCallback);
}
//
// Try to win over Dispose is there is a ----
//
if (Interlocked.CompareExchange(ref m_IntCleanedUp, 2, 0) != 0)
{
GlobalLog.Leave("Socket#" + ValidationHelper.HashString(this) + "::SetAsyncEventSelect() Already Cleaned up, returning ... ", string.Empty);
return false;
}
try
{
m_BlockEventBits = blockEventBits;
m_RegisteredWait = ThreadPool.UnsafeRegisterWaitForSingleObject(m_AsyncEvent, s_RegisteredWaitCallback, this, Timeout.Infinite, true);
}
finally
{
//
// Release dispose if any is waiting
//
Interlocked.Exchange(ref m_IntCleanedUp, 0);
}
SocketError errorCode = SocketError.NotSocket;
//
// issue the native call
//
try {
errorCode = UnsafeNclNativeMethods.OSSOCK.WSAEventSelect(m_Handle, m_AsyncEvent.SafeWaitHandle, blockEventBits);
}
catch (Exception e)
{
if (NclUtilities.IsFatal(e))
throw;
GlobalLog.Print("Socket#" + ValidationHelper.HashString(this) + "::SetAsyncEventSelect() !!! (converting to ObjectDisposed) Exception :" + e.ToString());
GlobalLog.Assert(CleanedUp, "Socket#{0}::SetAsyncEventSelect|WSAEventSelect got exception and CleanedUp not set.", ValidationHelper.HashString(this));
}
if (errorCode==SocketError.SocketError) {
//
// update our internal state after this socket error
// we won't throw since this is an internal method
//
UpdateStatusAfterSocketError(errorCode);
}
//
// the call to WSAEventSelect will put us in non-blocking mode,
// hence we need update internal status
//
willBlockInternal = false;
GlobalLog.Leave("Socket#" + ValidationHelper.HashString(this) + "::SetAsyncEventSelect", "m_BlockEventBits:" + m_BlockEventBits.ToString() + " willBlockInternal:" + willBlockInternal.ToString());
return errorCode == SocketError.Success;
}
//
// Does internal initalization before async winsock
// call to BeginConnect() or BeginAccept().
//
internal void SetAsyncEventSelect(AsyncEventBits blockEventBits) {
GlobalLog.Enter("Socket#" + ValidationHelper.HashString(this) + "::SetAsyncEventSelect", "blockEventBits:" + blockEventBits.ToString() + " m_BlockEventBits:" + m_BlockEventBits.ToString() + " willBlockInternal:" + willBlockInternal.ToString());
if (blockEventBits==m_BlockEventBits) {
//
// nothing for us to do, nothing is going to change
//
GlobalLog.Leave("Socket#" + ValidationHelper.HashString(this) + "::SetAsyncEventSelect", "nothing to do");
return;
}
//
// We need to select socket first, enabling us to listen to events
// then submit the event to the thread pool, and then finally
// call the function we wish to call.
// the following event is not used in Send/Receive async APIs
//
IntPtr eventHandle;
if (blockEventBits==AsyncEventBits.FdNone) {
//
// this will cancel any previous WSAEventSelect() and will put us back
// into blocking mode. custom build the native parameters
//
if (m_AsyncEvent!=null) {
m_AsyncEvent = null;
}
eventHandle = IntPtr.Zero;
}
else {
//
// this will put us into non-blocking mode.
// we'll need the real pointer here
//
if (m_AsyncEvent==null) {
m_AsyncEvent = new AutoResetEvent(false);
}
eventHandle = m_AsyncEvent.Handle;
}
//
// save blockEventBits
//
m_BlockEventBits = blockEventBits;
//
// issue the native call
//
int errorCode =
UnsafeNclNativeMethods.OSSOCK.WSAEventSelect(
m_Handle,
eventHandle,
m_BlockEventBits );
if (errorCode==SocketErrors.SocketError) {
//
// update our internal state after this socket error
// we won't throw since this is an internal method
//
UpdateStatusAfterSocketError();
}
//
// the call to WSAEventSelect might have caused us to change
// blocking mode, hence we need update internal status
//
willBlockInternal = willBlockInternal && m_BlockEventBits==AsyncEventBits.FdNone;
GlobalLog.Leave("Socket#" + ValidationHelper.HashString(this) + "::SetAsyncEventSelect", "m_BlockEventBits:" + m_BlockEventBits.ToString() + " willBlockInternal:" + willBlockInternal.ToString());
}