/// <summary>
/// Saves the current <see cref="IExceptionHandlerInfo"/> instance.
/// </summary>
/// <param name="targetMethod">The target method.</param>
/// <param name="emitter">The <see cref="IEmitInvocationInfo"/> instance that will emit the current method context.</param>
private void SaveExceptionInfo(MethodDefinition targetMethod, IEmitInvocationInfo emitter)
{
var IL = targetMethod.GetILGenerator();
var module = IL.GetModule();
emitter.Emit(targetMethod, targetMethod, _invocationInfo);
IL.Emit(OpCodes.Ldloc, _exception);
IL.Emit(OpCodes.Ldloc, _invocationInfo);
var exceptionInfoConstructor = module.ImportConstructor <ExceptionHandlerInfo>(
typeof(Exception),
typeof(IInvocationInfo));
IL.Emit(OpCodes.Newobj, exceptionInfoConstructor);
IL.Emit(OpCodes.Stloc, _exceptionInfo);
var returnType = targetMethod.ReturnType.ReturnType;
if (returnType == _voidType || _returnValue == null)
{
return;
}
// exceptionInfo.ReturnValue = returnValue;
var setReturnValue = module.ImportMethod <IExceptionHandlerInfo>("set_ReturnValue");
IL.Emit(OpCodes.Ldloc, _exceptionInfo);
IL.Emit(OpCodes.Ldloc, _returnValue);
IL.Emit(OpCodes.Callvirt, setReturnValue);
}
/// <summary>
/// Emits the IL instructions that will store information about the method <paramref name="targetMethod">currently being executed</paramref>
/// and stores the results into the <paramref name="invocationInfo">variable.</paramref>
/// </summary>
/// <param name="emitter">The <see cref="IEmitInvocationInfo"/> instance.</param>
/// <param name="method">The method whose implementation will be intercepted.</param>
/// <param name="targetMethod">The actual method that will contain the resulting instructions.</param>
/// <param name="invocationInfo">The <see cref="VariableDefinition">local variable</see> that will store the current <see cref="IInvocationInfo"/> instance.</param>
public static void Emit(this IEmitInvocationInfo emitter, MethodInfo method, MethodDefinition targetMethod, VariableDefinition invocationInfo)
{
var module = targetMethod.DeclaringType.Module;
var interceptedMethod = module.Import(method);
emitter.Emit(targetMethod, interceptedMethod, invocationInfo);
}
public void Rewrite(MethodDefinition method, CilWorker IL,
IEnumerable <Instruction> oldInstructions)
{
var targetMethod = _parameters.TargetMethod;
var worker = targetMethod.GetILGenerator();
var module = worker.GetModule();
_getInterceptionDisabled.Emit(worker);
// Construct the InvocationInfo instance
var skipInvocationInfo = worker.Create(OpCodes.Nop);
worker.Emit(OpCodes.Ldloc, _parameters.InterceptionDisabled);
worker.Emit(OpCodes.Brtrue, skipInvocationInfo);
var interceptedMethod = targetMethod;
_emitter.Emit(targetMethod, interceptedMethod, _parameters.InvocationInfo);
var skipGetReplacementProvider = IL.Create(OpCodes.Nop);
// var provider = this.MethodReplacementProvider;
//IL.Emit(OpCodes.Ldloc, _interceptionDisabled);
//IL.Emit(OpCodes.Brtrue, skipGetReplacementProvider);
_getInstanceMethodReplacementProvider.Emit(IL);
_surroundMethodBody.AddProlog(worker);
IL.Append(skipGetReplacementProvider);
worker.Append(skipInvocationInfo);
_getClassMethodReplacementProvider.Emit(worker);
var returnType = targetMethod.ReturnType.ReturnType;
_addMethodReplacement.Emit(worker);
// Save the return value
TypeReference voidType = module.Import(typeof(void));
_surroundMethodBody.AddEpilog(worker);
if (returnType != voidType)
{
worker.Emit(OpCodes.Ldloc, _parameters.ReturnValue);
}
worker.Emit(OpCodes.Ret);
}
/// <summary>
/// Saves the current <see cref="IExceptionHandlerInfo"/> instance.
/// </summary>
/// <param name="targetMethod">The target method.</param>
/// <param name="emitter">The <see cref="IEmitInvocationInfo"/> instance that will emit the current method context.</param>
private void SaveExceptionInfo(MethodDefinition targetMethod, IEmitInvocationInfo emitter)
{
var IL = targetMethod.GetILGenerator();
var module = IL.GetModule();
emitter.Emit(targetMethod, targetMethod, _invocationInfo);
IL.Emit(OpCodes.Ldloc, _exception);
IL.Emit(OpCodes.Ldloc, _invocationInfo);
var exceptionInfoConstructor = module.ImportConstructor<ExceptionHandlerInfo>(
typeof (Exception),
typeof (IInvocationInfo));
IL.Emit(OpCodes.Newobj, exceptionInfoConstructor);
IL.Emit(OpCodes.Stloc, _exceptionInfo);
var returnType = targetMethod.ReturnType.ReturnType;
if (returnType == _voidType || _returnValue == null)
return;
// exceptionInfo.ReturnValue = returnValue;
var setReturnValue = module.ImportMethod<IExceptionHandlerInfo>("set_ReturnValue");
IL.Emit(OpCodes.Ldloc, _exceptionInfo);
IL.Emit(OpCodes.Ldloc, _returnValue);
IL.Emit(OpCodes.Callvirt, setReturnValue);
}