private void DoCompletion(int targetState)
{
if (WaitHandleAsyncOperations.TryChangeState(ref _state, expectedState: State_Waiting, newState: State_Completing))
{
_waitRegistration.Unregister(null);
_ctRegistration.Dispose();
_state = targetState;
InvokeContinuation();
}
}
/// <summary>
/// Starts waiting on the <see cref="System.Threading.WaitHandle"/> to pulse on a separate thread
/// </summary>
/// <param name="waitHandle">The <see cref="System.Threading.WaitHandle"/> to wait on</param>
/// <param name="timeoutMs">The wait timeout, or -1 to wait indefinitely</param>
/// <param name="cancellationToken">The wait cancellation token</param>
/// <returns>An instance of the awaiter</returns>
internal static WaitHandleAwaiter StartWaiting(WaitHandle waitHandle, int timeoutMs, CancellationToken cancellationToken)
{
WaitHandleAsyncOperations.ThrowIfMutex(waitHandle);
cancellationToken.ThrowIfCancellationRequested();
var awaiter = new WaitHandleAwaiter()
{
_waitHandle = waitHandle, _timeoutMs = timeoutMs
};
awaiter._waitRegistration = ThreadPool.RegisterWaitForSingleObject(waitHandle, WaitCallback, awaiter, timeoutMs, executeOnlyOnce: true);
if (cancellationToken.CanBeCanceled)
{
awaiter._ctRegistration = cancellationToken.Register(awaiter.OnCancelRequested, useSynchronizationContext: false);
}
return(awaiter);
}