/// <summary>
/// Returns the candidate callees after resolving the specified invocation.
/// </summary>
/// <param name="invocation">InvocationExpressionSyntax</param>
/// <param name="node">IDataFlowNode</param>
/// <returns>Set of candidate callees</returns>
private static HashSet <MethodDeclarationSyntax> ResolveCandidateMethodsAtCallSite(
InvocationExpressionSyntax invocation, IDataFlowNode node)
{
var candidateCallees = new HashSet <MethodDeclarationSyntax>();
var candidateMethodDeclaration = MethodSummaryResolver.ResolveMethodDeclaration(
invocation, node) as MethodDeclarationSyntax;
if (candidateMethodDeclaration == null)
{
return(candidateCallees);
}
if (candidateMethodDeclaration.Modifiers.Any(SyntaxKind.AbstractKeyword) ||
candidateMethodDeclaration.Modifiers.Any(SyntaxKind.VirtualKeyword) ||
candidateMethodDeclaration.Modifiers.Any(SyntaxKind.OverrideKeyword))
{
HashSet <MethodDeclarationSyntax> overriders = null;
if (!MethodSummaryResolver.TryGetCandidateMethodOverriders(out overriders,
invocation, node))
{
return(candidateCallees);
}
candidateCallees.UnionWith(overriders);
}
if (candidateCallees.Count == 0)
{
candidateCallees.Add(candidateMethodDeclaration);
}
return(candidateCallees);
}
/// <summary>
/// Returns all cached method summaries for the specified call.
/// </summary>
/// <param name="call">ExpressionSyntax</param>
/// <param name="node">IDataFlowNode</param>
/// <returns>MethodSummarys</returns>
private static ISet <MethodSummary> ResolveMethodSummaries(ExpressionSyntax call, IDataFlowNode node)
{
var summaries = new HashSet <MethodSummary>();
var invocation = call as InvocationExpressionSyntax;
var objCreation = call as ObjectCreationExpressionSyntax;
var callSymbol = node.Summary.SemanticModel.GetSymbolInfo(call).Symbol;
if (callSymbol == null ||
(invocation == null && objCreation == null))
{
return(summaries);
}
if (node.MethodSummaryCache.ContainsKey(callSymbol))
{
summaries.UnionWith(node.MethodSummaryCache[callSymbol]);
}
else if (invocation != null)
{
var parameterTypes = MethodSummaryResolver.GetCandidateParameterTypes(
invocation.ArgumentList, node);
var candidateCalleeDeclarations = MethodSummaryResolver.
ResolveCandidateMethodsAtCallSite(invocation, node);
foreach (var candidateCalleeDeclaration in candidateCalleeDeclarations)
{
var calleeSummary = MethodSummary.Create(node.Summary.AnalysisContext,
candidateCalleeDeclaration, parameterTypes);
if (calleeSummary != null)
{
summaries.Add(calleeSummary);
}
}
}
else
{
var parameterTypes = MethodSummaryResolver.GetCandidateParameterTypes(
objCreation.ArgumentList, node);
var constructor = MethodSummaryResolver.ResolveMethodDeclaration(
objCreation, node) as ConstructorDeclarationSyntax;
if (constructor != null)
{
var calleeSummary = MethodSummary.Create(node.Summary.AnalysisContext,
constructor, parameterTypes);
if (calleeSummary != null)
{
summaries.Add(calleeSummary);
}
}
}
return(summaries);
}
/// <summary>
/// Returns all cached method summaries for the specified object creation.
/// </summary>
/// <param name="objCreation">ObjectCreationExpressionSyntax</param>
/// <param name="node">IDataFlowNode</param>
/// <returns>MethodSummarys</returns>
internal static ISet <MethodSummary> ResolveMethodSummaries(
ObjectCreationExpressionSyntax objCreation, IDataFlowNode node)
{
return(MethodSummaryResolver.ResolveMethodSummaries(objCreation as ExpressionSyntax, node));
}
/// <summary>
/// Returns all cached method summaries for the specified invocation.
/// </summary>
/// <param name="invocation">InvocationExpressionSyntax</param>
/// <param name="node">IDataFlowNode</param>
/// <returns>MethodSummarys</returns>
internal static ISet <MethodSummary> ResolveMethodSummaries(
InvocationExpressionSyntax invocation, IDataFlowNode node)
{
return(MethodSummaryResolver.ResolveMethodSummaries(invocation as ExpressionSyntax, node));
}
/// <summary>
/// Tries to get the list of candidate methods that can
/// override the specified virtual call.
/// </summary>
/// <param name="overriders">List of overrider methods</param>
/// <param name="virtualCall">Virtual call</param>
/// <param name="node">IDataFlowNode</param>
/// <returns>Boolean</returns>
private static bool TryGetCandidateMethodOverriders(out HashSet <MethodDeclarationSyntax> overriders,
InvocationExpressionSyntax virtualCall, IDataFlowNode node)
{
overriders = new HashSet <MethodDeclarationSyntax>();
ISymbol calleeSymbol = null;
SimpleNameSyntax callee = null;
bool isThis = false;
if (virtualCall.Expression is MemberAccessExpressionSyntax)
{
var expr = virtualCall.Expression as MemberAccessExpressionSyntax;
var identifier = expr.Expression.DescendantNodesAndSelf().
OfType <IdentifierNameSyntax>().Last();
calleeSymbol = node.Summary.SemanticModel.GetSymbolInfo(identifier).Symbol;
if (expr.Expression is ThisExpressionSyntax)
{
callee = expr.Name;
isThis = true;
}
}
else
{
callee = virtualCall.Expression as IdentifierNameSyntax;
isThis = true;
}
if (isThis)
{
var typeDeclaration = node.Summary.Method.FirstAncestorOrSelf <TypeDeclarationSyntax>();
if (typeDeclaration != null)
{
foreach (var method in typeDeclaration.Members.OfType <MethodDeclarationSyntax>())
{
if (method.Identifier.ToString().Equals(callee.Identifier.ToString()))
{
overriders.Add(method);
return(true);
}
}
}
return(false);
}
var calleeDefinitions = node.DataFlowInfo.ResolveOutputAliases(calleeSymbol);
var calleeTypes = calleeDefinitions.SelectMany(def => def.CandidateTypes);
if (!calleeTypes.Any())
{
return(false);
}
foreach (var calleeType in calleeTypes)
{
MethodDeclarationSyntax method = null;
if (MethodSummaryResolver.TryGetMethodDeclarationFromType(
out method, calleeType, virtualCall, node))
{
overriders.Add(method);
}
}
return(true);
}
/// <summary>
/// Analyzes the data-flow in the method call.
/// </summary>
/// <param name="call">ExpressionSyntax</param>
/// <param name="node">IDataFlowNode</param>
/// <param name="returnSymbols">Return symbols</param>
/// <param name="returnTypes">Return types</param>
private void AnalyzeMethodCall(ExpressionSyntax call, IDataFlowNode node,
out ISet <ISymbol> returnSymbols, out ISet <ITypeSymbol> returnTypes)
{
returnSymbols = new HashSet <ISymbol>();
returnTypes = new HashSet <ITypeSymbol>();
var callSymbol = this.SemanticModel.GetSymbolInfo(call).Symbol;
if (callSymbol == null)
{
return;
}
var invocation = call as InvocationExpressionSyntax;
var objCreation = call as ObjectCreationExpressionSyntax;
ISet <MethodSummary> candidateCalleeSummaries;
if (invocation != null)
{
candidateCalleeSummaries = MethodSummaryResolver.ResolveMethodSummaries(invocation, node);
}
else
{
candidateCalleeSummaries = MethodSummaryResolver.ResolveMethodSummaries(objCreation, node);
}
ArgumentListSyntax argumentList;
if (invocation != null)
{
argumentList = invocation.ArgumentList;
}
else
{
argumentList = objCreation.ArgumentList;
}
this.ResolveGivesUpOwnershipInCall(callSymbol, argumentList, node);
foreach (var candidateCalleeSummary in candidateCalleeSummaries)
{
this.MapCalleeSummaryToCallSymbol(candidateCalleeSummary, callSymbol, node);
this.ResolveGivesUpOwnershipInCall(callSymbol, candidateCalleeSummary,
argumentList, node);
this.ResolveSideEffectsInCall(call, candidateCalleeSummary, node);
if (invocation != null)
{
returnSymbols.UnionWith(candidateCalleeSummary.GetResolvedReturnSymbols(
invocation, this.SemanticModel));
}
returnTypes.UnionWith(candidateCalleeSummary.SideEffectsInfo.ReturnTypes);
}
if (objCreation != null)
{
returnTypes.Add(this.SemanticModel.GetTypeInfo(call).Type);
}
if (invocation != null)
{
this.ResolveSideEffectsInExpression(invocation.Expression, node);
}
}