public void Decorate(TypeDefinition type, MethodDefinition method, CustomAttribute attribute, bool explicitMatch)
{
method.Body.InitLocals = true;
var parametersArrayTypeRef = new ArrayType(objectTypeRef);
var initMethodRef1 = referenceFinder.GetOptionalMethodReference(attribute.AttributeType,
md => md.Name == "Init" && md.Parameters.Count == 1 && md.Parameters[0].ParameterType.FullName == typeof(MethodBase).FullName);
var initMethodRef2 = referenceFinder.GetOptionalMethodReference(attribute.AttributeType,
md => md.Name == "Init" && md.Parameters.Count == 2 && md.Parameters[0].ParameterType.FullName == typeof(object).FullName);
var initMethodRef3 = referenceFinder.GetOptionalMethodReference(attribute.AttributeType,
md => md.Name == "Init" && md.Parameters.Count == 3);
var needBypassRef0 = referenceFinder.GetOptionalMethodReference(attribute.AttributeType,
md => md.Name == "NeedBypass" && md.Parameters.Count == 0);
var onEntryMethodRef0 = referenceFinder.GetOptionalMethodReference(attribute.AttributeType,
md => md.Name == "OnEntry" && md.Parameters.Count == 0);
var onExitMethodRef0 = referenceFinder.GetOptionalMethodReference(attribute.AttributeType,
md => md.Name == "OnExit" && md.Parameters.Count == 0);
var onExitMethodRef1 = referenceFinder.GetOptionalMethodReference(attribute.AttributeType,
md => md.Name == "OnExit" && md.Parameters.Count == 1 && md.Parameters[0].ParameterType.FullName == typeof(object).FullName);
var alterRetvalRef1 = referenceFinder.GetOptionalMethodReference(attribute.AttributeType,
md => md.Name == "AlterRetval" && md.Parameters.Count == 1);
var onExceptionMethodRef = referenceFinder.GetOptionalMethodReference(attribute.AttributeType,
md => md.Name == "OnException" && md.Parameters.Count == 1 && md.Parameters[0].ParameterType.FullName == typeof(Exception).FullName);
var taskContinuationMethodRef = referenceFinder.GetOptionalMethodReference(attribute.AttributeType, md => md.Name == "OnTaskContinuation");
var attributeVariableDefinition = AddVariableDefinition(method, "__fody$attribute", attribute.AttributeType);
var methodVariableDefinition = AddVariableDefinition(method, "__fody$method", methodBaseTypeRef);
VariableDefinition exceptionVariableDefinition = null;
VariableDefinition parametersVariableDefinition = null;
VariableDefinition retvalVariableDefinition = null;
if (initMethodRef3 != null)
{
parametersVariableDefinition = AddVariableDefinition(method, "__fody$parameters", parametersArrayTypeRef);
}
if (onExceptionMethodRef != null)
{
exceptionVariableDefinition = AddVariableDefinition(method, "__fody$exception", exceptionTypeRef);
}
var needCatchReturn = null != (onExitMethodRef1 ?? onExitMethodRef0 ?? onExceptionMethodRef ?? taskContinuationMethodRef ?? alterRetvalRef1 ?? needBypassRef0);
if (method.ReturnType.FullName != "System.Void" && needCatchReturn)
{
retvalVariableDefinition = AddVariableDefinition(method, "__fody$retval", method.ReturnType);
}
method.Body.SimplifyMacros();
var processor = method.Body.GetILProcessor();
var methodBodyFirstInstruction = method.Body.Instructions.First();
if (method.IsConstructor)
{
var callBase = method.Body.Instructions.FirstOrDefault(
i => i.OpCode == OpCodes.Call &&
(i.Operand is MethodReference reference) &&
reference.Resolve().IsConstructor);
methodBodyFirstInstruction = callBase?.Next ?? methodBodyFirstInstruction;
}
var initAttributeVariable = GetAttributeInstanceInstructions(processor,
attribute,
method,
attributeVariableDefinition,
methodVariableDefinition,
explicitMatch);
List <Instruction> callInitInstructions = null;
List <Instruction> createParametersArrayInstructions = null;
List <Instruction> callOnEntryInstructions = null;
List <Instruction> saveRetvalInstructions = null;
List <Instruction> callOnExitInstructions = null;
if (parametersVariableDefinition != null)
{
createParametersArrayInstructions = CreateParametersArrayInstructions(
processor,
method,
parametersVariableDefinition).ToList();
}
var initMethodRef = initMethodRef3 ?? initMethodRef2 ?? initMethodRef1;
if (initMethodRef != null)
{
callInitInstructions = GetCallInitInstructions(
processor,
type,
method,
attributeVariableDefinition,
methodVariableDefinition,
parametersVariableDefinition,
initMethodRef).ToList();
}
if (onEntryMethodRef0 != null)
{
callOnEntryInstructions = GetCallOnEntryInstructions(processor, attributeVariableDefinition, onEntryMethodRef0).ToList();
}
if (retvalVariableDefinition != null)
{
saveRetvalInstructions = GetSaveRetvalInstructions(processor, retvalVariableDefinition).ToList();
}
if (retvalVariableDefinition != null && onExitMethodRef1 != null)
{
callOnExitInstructions = GetCallOnExitInstructions(processor, attributeVariableDefinition, onExitMethodRef1, retvalVariableDefinition).ToList();
}
else if (onExitMethodRef0 != null)
{
callOnExitInstructions = GetCallOnExitInstructions(processor, attributeVariableDefinition, onExitMethodRef0).ToList();
}
List <Instruction> methodBodyReturnInstructions = null;
List <Instruction> tryCatchLeaveInstructions = null;
List <Instruction> catchHandlerInstructions = null;
List <Instruction> bypassInstructions = null;
if (needCatchReturn)
{
methodBodyReturnInstructions = GetMethodBodyReturnInstructions(processor, attributeVariableDefinition, retvalVariableDefinition, alterRetvalRef1).ToList();
if (needBypassRef0 != null)
{
bypassInstructions = GetBypassInstructions(processor, attributeVariableDefinition, needBypassRef0, methodBodyReturnInstructions.First()).ToList();
}
if (onExceptionMethodRef != null)
{
tryCatchLeaveInstructions = GetTryCatchLeaveInstructions(processor, methodBodyReturnInstructions.First()).ToList();
catchHandlerInstructions = GetCatchHandlerInstructions(processor,
attributeVariableDefinition, exceptionVariableDefinition, onExceptionMethodRef);
}
ReplaceRetInstructions(processor, saveRetvalInstructions?.FirstOrDefault() ?? callOnExitInstructions?.FirstOrDefault() ?? methodBodyReturnInstructions.First());
}
processor.InsertBefore(methodBodyFirstInstruction, initAttributeVariable);
if (createParametersArrayInstructions != null)
{
processor.InsertBefore(methodBodyFirstInstruction, createParametersArrayInstructions);
}
if (callInitInstructions != null)
{
processor.InsertBefore(methodBodyFirstInstruction, callInitInstructions);
}
if (bypassInstructions != null)
{
processor.InsertBefore(methodBodyFirstInstruction, bypassInstructions);
}
if (callOnEntryInstructions != null)
{
processor.InsertBefore(methodBodyFirstInstruction, callOnEntryInstructions);
}
if (methodBodyReturnInstructions != null)
{
processor.InsertAfter(method.Body.Instructions.Last(), methodBodyReturnInstructions);
if (saveRetvalInstructions != null)
{
processor.InsertBefore(methodBodyReturnInstructions.First(), saveRetvalInstructions);
}
if (taskContinuationMethodRef != null)
{
var taskContinuationInstructions = GetTaskContinuationInstructions(
processor,
retvalVariableDefinition,
attributeVariableDefinition,
taskContinuationMethodRef);
processor.InsertBefore(methodBodyReturnInstructions.First(), taskContinuationInstructions);
}
if (callOnExitInstructions != null)
{
processor.InsertBefore(methodBodyReturnInstructions.First(), callOnExitInstructions);
}
if (onExceptionMethodRef != null)
{
processor.InsertBefore(methodBodyReturnInstructions.First(), tryCatchLeaveInstructions);
processor.InsertBefore(methodBodyReturnInstructions.First(), catchHandlerInstructions);
method.Body.ExceptionHandlers.Add(new ExceptionHandler(ExceptionHandlerType.Catch)
{
CatchType = exceptionTypeRef,
TryStart = methodBodyFirstInstruction,
TryEnd = tryCatchLeaveInstructions.Last().Next,
HandlerStart = catchHandlerInstructions.First(),
HandlerEnd = catchHandlerInstructions.Last().Next
});
}
}
method.Body.OptimizeMacros();
}