public override void Initialize(AnalysisContext context)
{
context.EnableConcurrentExecution();
context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.Analyze);
context.RegisterCompilationStartAction(compilationContext =>
{
if (!DisposeAnalysisHelper.TryGetOrCreate(compilationContext.Compilation, out DisposeAnalysisHelper disposeAnalysisHelper))
{
return;
}
var fieldDisposeValueMap = new ConcurrentDictionary <IFieldSymbol, /*disposed*/ bool>();
void addOrUpdateFieldDisposedValue(IFieldSymbol field, bool disposed)
{
Debug.Assert(!field.IsStatic);
Debug.Assert(field.Type.IsDisposable(disposeAnalysisHelper.IDisposable));
fieldDisposeValueMap.AddOrUpdate(field,
addValue: disposed,
updateValueFactory: (f, currentValue) => currentValue || disposed);
};
var hasErrors = false;
compilationContext.RegisterOperationAction(_ => hasErrors = true, OperationKind.Invalid);
// Disposable fields with initializer at declaration must be disposed.
compilationContext.RegisterOperationAction(operationContext =>
{
if (!ShouldAnalyze(operationContext.ContainingSymbol.ContainingType))
{
return;
}
var initializedFields = ((IFieldInitializerOperation)operationContext.Operation).InitializedFields;
foreach (var field in initializedFields)
{
if (!field.IsStatic &&
disposeAnalysisHelper.GetDisposableFields(field.ContainingType).Contains(field))
{
addOrUpdateFieldDisposedValue(field, disposed: false);
}
}
},
OperationKind.FieldInitializer);
// Instance fields initialized in constructor/method body with a locally created disposable object must be disposed.
compilationContext.RegisterOperationBlockStartAction(operationBlockStartContext =>
{
if (!(operationBlockStartContext.OwningSymbol is IMethodSymbol containingMethod) ||
!ShouldAnalyze(containingMethod.ContainingType))
{
return;
}
if (disposeAnalysisHelper.HasAnyDisposableCreationDescendant(operationBlockStartContext.OperationBlocks, containingMethod))
{
PointsToAnalysisResult lazyPointsToAnalysisResult = null;
operationBlockStartContext.RegisterOperationAction(operationContext =>
{
var fieldReference = (IFieldReferenceOperation)operationContext.Operation;
var field = fieldReference.Field;
// Only track instance fields on the current instance.
if (field.IsStatic || fieldReference.Instance?.Kind != OperationKind.InstanceReference)
{
return;
}
// Check if this is a Disposable field that is not currently being tracked.
if (fieldDisposeValueMap.ContainsKey(field) ||
!disposeAnalysisHelper.GetDisposableFields(field.ContainingType).Contains(field))
{
return;
}
// We have a field reference for a disposable field.
// Check if it is being assigned a locally created disposable object.
if (fieldReference.Parent is ISimpleAssignmentOperation simpleAssignmentOperation &&
simpleAssignmentOperation.Target == fieldReference)
{
if (lazyPointsToAnalysisResult == null)
{
var cfg = operationBlockStartContext.OperationBlocks.GetControlFlowGraph();
var wellKnownTypeProvider = WellKnownTypeProvider.GetOrCreate(operationContext.Compilation);
var interproceduralAnalysisConfig = InterproceduralAnalysisConfiguration.Create(
operationBlockStartContext.Options, Rule, InterproceduralAnalysisKind.None, operationBlockStartContext.CancellationToken);
var pointsToAnalysisResult = PointsToAnalysis.TryGetOrComputeResult(cfg,
containingMethod, operationBlockStartContext.Options, wellKnownTypeProvider, interproceduralAnalysisConfig,
interproceduralAnalysisPredicateOpt: null,
pessimisticAnalysis: false, performCopyAnalysis: false);
if (pointsToAnalysisResult == null)
{
hasErrors = true;
return;
}
Interlocked.CompareExchange(ref lazyPointsToAnalysisResult, pointsToAnalysisResult, null);
}
PointsToAbstractValue assignedPointsToValue = lazyPointsToAnalysisResult[simpleAssignmentOperation.Value.Kind, simpleAssignmentOperation.Value.Syntax];
foreach (var location in assignedPointsToValue.Locations)
{
if (disposeAnalysisHelper.IsDisposableCreationOrDisposeOwnershipTransfer(location, containingMethod))
{
addOrUpdateFieldDisposedValue(field, disposed: false);
break;
}
}
}
},
OperationKind.FieldReference);
}
// Mark fields disposed in Dispose method(s).
if (IsDisposeMethod(containingMethod))
{
var disposableFields = disposeAnalysisHelper.GetDisposableFields(containingMethod.ContainingType);
if (!disposableFields.IsEmpty)
{
if (disposeAnalysisHelper.TryGetOrComputeResult(operationBlockStartContext.OperationBlocks, containingMethod,
operationBlockStartContext.Options, Rule, trackInstanceFields: true, trackExceptionPaths: false, cancellationToken: operationBlockStartContext.CancellationToken,
disposeAnalysisResult: out var disposeAnalysisResult, pointsToAnalysisResult: out var pointsToAnalysisResult))
{
BasicBlock exitBlock = disposeAnalysisResult.ControlFlowGraph.GetExit();
foreach (var fieldWithPointsToValue in disposeAnalysisResult.TrackedInstanceFieldPointsToMap)
{
IFieldSymbol field = fieldWithPointsToValue.Key;
PointsToAbstractValue pointsToValue = fieldWithPointsToValue.Value;
Debug.Assert(field.Type.IsDisposable(disposeAnalysisHelper.IDisposable));
ImmutableDictionary <AbstractLocation, DisposeAbstractValue> disposeDataAtExit = disposeAnalysisResult.ExitBlockOutput.Data;
var disposed = false;
foreach (var location in pointsToValue.Locations)
{
if (disposeDataAtExit.TryGetValue(location, out DisposeAbstractValue disposeValue))
{
switch (disposeValue.Kind)
{
// For MaybeDisposed, conservatively mark the field as disposed as we don't support path sensitive analysis.
case DisposeAbstractValueKind.MaybeDisposed:
case DisposeAbstractValueKind.Unknown:
case DisposeAbstractValueKind.Escaped:
case DisposeAbstractValueKind.Disposed:
disposed = true;
addOrUpdateFieldDisposedValue(field, disposed);
break;
}
}
if (disposed)
{
break;
}
}
}
}
}
}
});
compilationContext.RegisterCompilationEndAction(compilationEndContext =>
{
if (hasErrors)
{
return;
}
foreach (var kvp in fieldDisposeValueMap)
{
IFieldSymbol field = kvp.Key;
bool disposed = kvp.Value;
// Flag non-disposed fields only if the containing type has a Dispose method implementation.
if (!disposed &&
HasDisposeMethod(field.ContainingType))
{
// '{0}' contains field '{1}' that is of IDisposable type '{2}', but it is never disposed. Change the Dispose method on '{0}' to call Close or Dispose on this field.
var arg1 = field.ContainingType.ToDisplayString(SymbolDisplayFormat.MinimallyQualifiedFormat);
var arg2 = field.Name;
var arg3 = field.Type.ToDisplayString(SymbolDisplayFormat.MinimallyQualifiedFormat);
var diagnostic = field.CreateDiagnostic(Rule, arg1, arg2, arg3);
compilationEndContext.ReportDiagnostic(diagnostic);
}
}
});
return;
// Local functions
bool ShouldAnalyze(INamedTypeSymbol namedType)
{
// We only want to analyze types which are disposable (implement System.IDisposable directly or indirectly)
// and have at least one disposable field.
return(!hasErrors &&
namedType.IsDisposable(disposeAnalysisHelper.IDisposable) &&
!disposeAnalysisHelper.GetDisposableFields(namedType).IsEmpty&&
!namedType.IsConfiguredToSkipAnalysis(compilationContext.Options, Rule, compilationContext.Compilation, compilationContext.CancellationToken));
}
bool IsDisposeMethod(IMethodSymbol method)
=> method.GetDisposeMethodKind(disposeAnalysisHelper.IDisposable, disposeAnalysisHelper.Task) != DisposeMethodKind.None;
bool HasDisposeMethod(INamedTypeSymbol namedType)
{
foreach (var method in namedType.GetMembers().OfType <IMethodSymbol>())
{
if (IsDisposeMethod(method))
{
return(true);
}
}
return(false);
}
});
}
public override void Initialize(AnalysisContext context)
{
context.EnableConcurrentExecution();
context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
context.RegisterCompilationStartAction(compilationContext =>
{
if (!DisposeAnalysisHelper.TryGetOrCreate(compilationContext.Compilation, out DisposeAnalysisHelper disposeAnalysisHelper))
{
return;
}
var fieldDisposeValueMap = new ConcurrentDictionary <IFieldSymbol, /*disposed*/ bool>();
void addOrUpdateFieldDisposedValue(IFieldSymbol field, bool disposed)
{
Debug.Assert(!field.IsStatic);
Debug.Assert(field.Type.IsDisposable(disposeAnalysisHelper.IDisposable));
fieldDisposeValueMap.AddOrUpdate(field,
addValue: disposed,
updateValueFactory: (f, currentValue) => currentValue || disposed);
};
// Disposable fields with initializer at declaration must be disposed.
compilationContext.RegisterOperationAction(operationContext =>
{
var initializedFields = ((IFieldInitializerOperation)operationContext.Operation).InitializedFields;
foreach (var field in initializedFields)
{
if (!field.IsStatic &&
disposeAnalysisHelper.GetDisposableFields(field.ContainingType).Contains(field))
{
addOrUpdateFieldDisposedValue(field, disposed: false);
}
}
},
OperationKind.FieldInitializer);
// Instance fields initialized in constructor/method body with a locally created disposable object must be disposed.
compilationContext.RegisterOperationBlockStartAction(operationBlockStartContext =>
{
if (!(operationBlockStartContext.OwningSymbol is IMethodSymbol containingMethod))
{
return;
}
if (disposeAnalysisHelper.HasAnyDisposableCreationDescendant(operationBlockStartContext.OperationBlocks, containingMethod))
{
DataFlowAnalysisResult <DisposeBlockAnalysisResult, DisposeAbstractValue> disposeAnalysisResult;
DataFlowAnalysisResult <PointsToBlockAnalysisResult, PointsToAbstractValue> pointsToAnalysisResult;
if (disposeAnalysisHelper.TryGetOrComputeResult(operationBlockStartContext.OperationBlocks, containingMethod, out disposeAnalysisResult, out pointsToAnalysisResult))
{
Debug.Assert(disposeAnalysisResult != null);
Debug.Assert(pointsToAnalysisResult != null);
operationBlockStartContext.RegisterOperationAction(operationContext =>
{
var fieldReference = (IFieldReferenceOperation)operationContext.Operation;
var field = fieldReference.Field;
// Only track instance fields on the current instance.
if (field.IsStatic || fieldReference.Instance?.Kind != OperationKind.InstanceReference)
{
return;
}
// Check if this is a Disposable field that is not currently being tracked.
if (fieldDisposeValueMap.ContainsKey(field) ||
!disposeAnalysisHelper.GetDisposableFields(field.ContainingType).Contains(field))
{
return;
}
// We have a field reference for a disposable field.
// Check if it is being assigned a locally created disposable object.
if (fieldReference.Parent is ISimpleAssignmentOperation simpleAssignmentOperation &&
simpleAssignmentOperation.Target == fieldReference)
{
PointsToAbstractValue assignedPointsToValue = pointsToAnalysisResult[simpleAssignmentOperation.Value];
foreach (var location in assignedPointsToValue.Locations)
{
if (disposeAnalysisHelper.IsDisposableCreationOrDisposeOwnershipTransfer(location, containingMethod))
{
addOrUpdateFieldDisposedValue(field, disposed: false);
break;
}
}
}
},
OperationKind.FieldReference);
}
}
// Mark fields disposed in Dispose method(s).
if (containingMethod.GetDisposeMethodKind(disposeAnalysisHelper.IDisposable, disposeAnalysisHelper.Task) != DisposeMethodKind.None)
{
var disposableFields = disposeAnalysisHelper.GetDisposableFields(containingMethod.ContainingType);
if (!disposableFields.IsEmpty)
{
DataFlowAnalysisResult <DisposeBlockAnalysisResult, DisposeAbstractValue> disposeAnalysisResult;
DataFlowAnalysisResult <PointsToBlockAnalysisResult, PointsToAbstractValue> pointsToAnalysisResult;
ImmutableDictionary <IFieldSymbol, PointsToAbstractValue> trackedInstanceFieldPointsToMap;
if (disposeAnalysisHelper.TryGetOrComputeResult(operationBlockStartContext.OperationBlocks, containingMethod, trackInstanceFields: true,
disposeAnalysisResult: out disposeAnalysisResult, pointsToAnalysisResult: out pointsToAnalysisResult, trackedInstanceFieldPointsToMap: out trackedInstanceFieldPointsToMap))
{
BasicBlock exitBlock = disposeAnalysisResult.ControlFlowGraph.Exit;
foreach (var fieldWithPointsToValue in trackedInstanceFieldPointsToMap)
{
IFieldSymbol field = fieldWithPointsToValue.Key;
PointsToAbstractValue pointsToValue = fieldWithPointsToValue.Value;
Debug.Assert(field.Type.IsDisposable(disposeAnalysisHelper.IDisposable));
ImmutableDictionary <AbstractLocation, DisposeAbstractValue> disposeDataAtExit = disposeAnalysisResult[exitBlock].OutputData;
var disposed = false;
foreach (var location in pointsToValue.Locations)
{
if (disposeDataAtExit.TryGetValue(location, out DisposeAbstractValue disposeValue))
{
switch (disposeValue.Kind)
{
// For MaybeDisposed, conservatively mark the field as disposed as we don't support path sensitive analysis.
case DisposeAbstractValueKind.MaybeDisposed:
case DisposeAbstractValueKind.Disposed:
disposed = true;
addOrUpdateFieldDisposedValue(field, disposed);
break;
}
}
if (disposed)
{
break;
}
}
}
}
}
}
});
compilationContext.RegisterCompilationEndAction(compilationEndContext =>
{
foreach (var kvp in fieldDisposeValueMap)
{
IFieldSymbol field = kvp.Key;
bool disposed = kvp.Value;
if (!disposed)
{
// '{0}' contains field '{1}' that is of IDisposable type '{2}', but it is never disposed. Change the Dispose method on '{0}' to call Close or Dispose on this field.
var arg1 = field.ContainingType.ToDisplayString(SymbolDisplayFormat.MinimallyQualifiedFormat);
var arg2 = field.Name;
var arg3 = field.Type.ToDisplayString(SymbolDisplayFormat.MinimallyQualifiedFormat);
var diagnostic = field.CreateDiagnostic(Rule, arg1, arg2, arg3);
compilationEndContext.ReportDiagnostic(diagnostic);
}
}
});
});
}