public RuleResult CheckMethod(MethodDefinition method)
{
// rule does not apply to method without IL (e.g. p/invoke) or generated code (e.g. compiler or tools)
if (!method.HasBody || method.IsGeneratedCode())
{
return(RuleResult.DoesNotApply);
}
// avoid looping if we're sure there's no call in the method
if (!OpCodeBitmask.Calls.Intersect(OpCodeEngine.GetBitmask(method)))
{
return(RuleResult.DoesNotApply);
}
foreach (Instruction ins in method.Body.Instructions)
{
if ((ins.OpCode.Code != Code.Callvirt) && (ins.OpCode.Code != Code.Call))
{
continue;
}
// look for calls to .Invoke
MethodReference mr = (ins.Operand as MethodReference);
if (!MethodSignatures.Invoke.Matches(mr))
{
continue;
}
// limit ourself to events
if (!mr.IsEventCallback())
{
continue;
}
// first check if we're looking from a variable or directly from
// the field (bad, it could be null)
Instruction caller = ins.TraceBack(method);
FieldDefinition field = caller.GetField();
if (field != null)
{
string msg = String.Format(CultureInfo.InvariantCulture, "Possible race condition since field '{0}' is accessed directly.", field.Name);
Runner.Report(method, ins, Severity.High, Confidence.High, msg);
}
else
{
// look for the variable, if it's not then stop analysis
VariableDefinition load = caller.GetVariable(method);
if ((load != null) && !CheckVariable(method, caller, load))
{
string name = String.Empty; // load.Name is not valid since Cecil 0.10
string msg = String.Format(CultureInfo.InvariantCulture, "Variable '{0}' does not seems to be checked against null.", name);
Runner.Report(method, ins, Severity.High, Confidence.Normal, msg);
}
}
}
return(Runner.CurrentRuleResult);
}
