/// <summary>
/// Removes the specified dependencies from this stage.
/// </summary>
/// <param name="dependee">The stage to remove dependencies for.</param>
/// <param name="dependencies">The dependencies to remove.</param>
public static void RemoveDependencies(this IPipelineStage dependee, params IPipelineStage[] dependencies)
{
lock (Dependencies)
{
foreach (var dependency in dependencies)
{
if (dependency == null)
{
IncrementOperation();
MarkPipelineAsUpdated();
throw new ArgumentNullException("Entry in dependency list", "One or more entries in the given dependency list was null.");
}
var strong = new AmbivalentPipelineReference(dependency, true);
if (!Dependencies.TryGetValue(strong, out var deps))
{
continue;
}
TotalWeakKeys -= deps.RemoveAll(r => !r.TryGetTarget(out var reference) || reference == dependee);
GC.KeepAlive(dependency);
}
IncrementOperation();
// TODO: remove this? Removed dependencies should never affect the propagation of the pipeline graph in any way.
MarkPipelineAsUpdated();
}
}
/// <summary>
/// Add dependencies for this pipeline stage, propagation on their invalidation.
/// </summary>
/// <param name="dependee">The stage to add dependencies for.</param>
/// <param name="dependencies">The dependencies to add.</param>
public static void AddDependencies(this IPipelineStage dependee, params IPipelineStage[] dependencies)
{
lock (Dependencies)
{
foreach (var dependency in dependencies)
{
if (dependency == null)
{
IncrementOperation();
MarkPipelineAsUpdated();
throw new ArgumentNullException("Entry in dependency list", "One or more entries in the given dependency list was null.");
}
var weak = new AmbivalentPipelineReference(dependency, false);
if (!Dependencies.TryGetValue(weak, out var deps))
{
deps = new List <WeakReference <IPipelineStage> >();
Dependencies.Add(weak, deps);
}
deps.Add(new WeakReference <IPipelineStage>(dependee));
++TotalWeakKeys;
GC.KeepAlive(dependency); //keep the reference alive at least until it can be added in the dictionary
}
IncrementOperation();
MarkPipelineAsUpdated();
}
}
private static IEnumerable <WeakReference <IPipelineStage> > InternalGetDependencies(IPipelineStage stage)
{
IncrementOperation();
var strong = new AmbivalentPipelineReference(stage, true);
if (!Dependencies.TryGetValue(strong, out var dependencies))
{
return(Enumerable.Empty <WeakReference <IPipelineStage> >());
}
TotalWeakKeys -= RemoveNonExisting(dependencies);
return(dependencies);
}