// No locks as we expect this class to be used linearly.
// If another CancellationTokenSource is created, we might have a CancellationToken outstanding
// that isn't cancelled if _cts.Cancel() is called. This happens only on the Abort paths, so it's not an issue.
private void InitializeCancellationToken(TimeSpan timeout)
{
if (timeout == TimeSpan.MaxValue || timeout == Timeout.InfiniteTimeSpan)
{
_cancellationToken = CancellationToken.None;
}
else if (timeout > TimeSpan.Zero)
{
_cts = new CancellationTokenSource();
_cancellationToken = _cts.Token;
TimeoutTokenSource.FromTimeout((int)timeout.TotalMilliseconds).Register(s_cancelOnTimeout, this);
}
else
{
_cancellationToken = new CancellationToken(true);
}
_cancellationTokenInitialized = true;
}
public async Task <CancellationToken> GetCancellationTokenAsync()
{
if (!_cancellationTokenInitialized)
{
var timeout = RemainingTime();
if (timeout >= MaxWait || timeout == Timeout.InfiniteTimeSpan)
{
_cancellationToken = CancellationToken.None;
}
else if (timeout > TimeSpan.Zero)
{
_cancellationToken = await TimeoutTokenSource.FromTimeoutAsync((int)timeout.TotalMilliseconds);
}
else
{
_cancellationToken = s_precancelledToken;
}
_cancellationTokenInitialized = true;
}
return(_cancellationToken);
}
