protected override void SetValueForParameterPointsToLocationOnEntry(IParameterSymbol parameter, PointsToAbstractValue pointsToAbstractValue)
{
if (DisposeOwnershipTransferLikelyTypes.Contains(parameter.Type) ||
(DisposeOwnershipTransferAtConstructor && parameter.ContainingSymbol.IsConstructor()))
{
SetAbstractValue(pointsToAbstractValue, DisposeAbstractValue.NotDisposed);
}
}
protected override void PostProcessArgument(IArgumentOperation operation, bool isEscaped)
{
base.PostProcessArgument(operation, isEscaped);
if (isEscaped)
{
PostProcessEscapedArgument();
}
return;
// Local functions.
void PostProcessEscapedArgument()
{
// Discover if a disposable object is being passed into the creation method for this new disposable object
// and if the new disposable object assumes ownership of that passed in disposable object.
if (IsDisposeOwnershipTransfer())
{
var pointsToValue = GetPointsToAbstractValue(operation.Value);
HandlePossibleEscapingOperation(operation, pointsToValue.Locations);
}
}
bool IsDisposeOwnershipTransfer()
{
if (!operation.Parameter.Type.IsDisposable(WellKnownTypeProvider.IDisposable))
{
return(false);
}
switch (operation.Parent)
{
case IObjectCreationOperation _:
return(DisposeOwnershipTransferAtConstructor ||
DisposeOwnershipTransferLikelyTypes.Contains(operation.Parameter.Type));
case IInvocationOperation invocation:
return(IsDisposableCreationSpecialCase(invocation.TargetMethod) &&
DisposeOwnershipTransferLikelyTypes.Contains(operation.Parameter.Type));
default:
return(false);
}
}
}
protected override void PostProcessArgument(IArgumentOperation operation, bool isEscaped)
{
base.PostProcessArgument(operation, isEscaped);
if (isEscaped)
{
// Discover if a disposable object is being passed into the creation method for this new disposable object
// and if the new disposable object assumes ownership of that passed in disposable object.
if (IsDisposeOwnershipTransfer())
{
var pointsToValue = GetPointsToAbstractValue(operation.Value);
HandlePossibleEscapingOperation(operation, pointsToValue.Locations);
return;
}
else if (FlowBranchConditionKind == ControlFlowConditionKind.WhenFalse &&
operation.Parameter.RefKind == RefKind.Out &&
operation.Parent is IInvocationOperation invocation &&
invocation.TargetMethod.ReturnType.SpecialType == SpecialType.System_Boolean)
{
// Case 1:
// // Assume 'obj' is not a valid object on the 'else' path.
// if (TryXXX(out IDisposable obj))
// {
// obj.Dispose();
// }
//
// return;
// Case 2:
// if (!TryXXX(out IDisposable obj))
// {
// return; // Assume 'obj' is not a valid object on this path.
// }
//
// obj.Dispose();
HandlePossibleInvalidatingOperation(operation);
return;
}
}
// Ref or out argument values from callee might be escaped by assigning to field.
if (operation.Parameter.RefKind == RefKind.Out || operation.Parameter.RefKind == RefKind.Ref)
{
HandlePossibleEscapingOperation(operation, GetEscapedLocations(operation));
}
return;
// Local functions.
bool IsDisposeOwnershipTransfer()
{
if (operation.Parameter.RefKind == RefKind.Out)
{
// Out arguments are always owned by the caller.
return(false);
}
return(operation.Parent switch
{
IObjectCreationOperation _ => DisposeOwnershipTransferAtConstructor ||
DisposeOwnershipTransferLikelyTypes.Contains(operation.Parameter.Type),
IInvocationOperation invocation => DisposeOwnershipTransferAtMethodCall ||
IsDisposableCreationSpecialCase(invocation.TargetMethod) && DisposeOwnershipTransferLikelyTypes.Contains(operation.Parameter.Type),
_ => false,
});
}
protected override void PostProcessArgument(IArgumentOperation operation, bool isEscaped)
{
base.PostProcessArgument(operation, isEscaped);
if (isEscaped)
{
// Discover if a disposable object is being passed into the creation method for this new disposable object
// and if the new disposable object assumes ownership of that passed in disposable object.
if (IsDisposeOwnershipTransfer())
{
var pointsToValue = GetPointsToAbstractValue(operation.Value);
HandlePossibleEscapingOperation(operation, pointsToValue.Locations);
}
else if (FlowBranchConditionKind == ControlFlowConditionKind.WhenFalse &&
operation.Parameter.RefKind == RefKind.Out &&
operation.Parent is IInvocationOperation invocation &&
invocation.TargetMethod.ReturnType.SpecialType == SpecialType.System_Boolean)
{
// Case 1:
// // Assume 'obj' is not a valid object on the 'else' path.
// if (TryXXX(out IDisposable obj))
// {
// obj.Dispose();
// }
//
// return;
// Case 2:
// if (!TryXXX(out IDisposable obj))
// {
// return; // Assume 'obj' is not a valid object on this path.
// }
//
// obj.Dispose();
HandlePossibleInvalidatingOperation(operation);
}
}
else if (operation.Parameter.RefKind == RefKind.Out || operation.Parameter.RefKind == RefKind.Ref)
{
HandlePossibleEscapingOperation(operation, GetEscapedLocations(operation));
}
return;
// Local functions.
bool IsDisposeOwnershipTransfer()
{
if (!operation.Parameter.Type.IsDisposable(WellKnownTypeProvider.IDisposable))
{
return(false);
}
switch (operation.Parent)
{
case IObjectCreationOperation _:
return(DisposeOwnershipTransferAtConstructor ||
DisposeOwnershipTransferLikelyTypes.Contains(operation.Parameter.Type));
case IInvocationOperation invocation:
return(IsDisposableCreationSpecialCase(invocation.TargetMethod) &&
DisposeOwnershipTransferLikelyTypes.Contains(operation.Parameter.Type));
default:
return(false);
}
}
}
