[System.Diagnostics.DebuggerDisplay ("IsCancellationRequested = {IsCancellationRequested}")]
public struct CancellationToken
{
+ bool canBeCanceled;
+ bool initialized;
+ CancellationTokenSource source;
+
public CancellationToken (bool canceled)
: this ()
{
- // dummy, this is actually set by CancellationTokenSource when the token is created
- Source = null;
+ initialized = true;
+ canBeCanceled = canceled;
+ // This is correctly set later if token originates from a Source
+ source = canceled ? CancellationTokenSource.CanceledSource : CancellationTokenSource.NoneSource;
}
public static CancellationToken None {
public void ThrowIfCancellationRequested ()
{
- if (Source.IsCancellationRequested)
+ if (initialized && Source.IsCancellationRequested)
throw new OperationCanceledException (this);
}
public bool CanBeCanceled {
get {
- return true;
+ return canBeCanceled;
}
}
public bool IsCancellationRequested {
get {
- return Source.IsCancellationRequested;
+ return initialized && Source.IsCancellationRequested;
}
}
}
internal CancellationTokenSource Source {
- get;
- set;
+ get {
+ if (!initialized)
+ CorrectlyInitialize ();
+ return source;
+ }
+ set {
+ source = value;
+ }
+ }
+
+ void CorrectlyInitialize ()
+ {
+ Source = CancellationTokenSource.NoneSource;
+ initialized = true;
}
}
}