private void ImplementCallback(ChordInfo chord)
{
MethodBuilder callback = target.DefineMethod(string.Format("{0}Callback", chord.Name),
MethodAttributes.Private, typeof (void),
new Type[] {typeof (object), typeof (bool)});
callback.DefineParameter(1, ParameterAttributes.In, "bus");
callback.DefineParameter(2, ParameterAttributes.In, "unused");
int joinParameterCount = chord.JoinParameters.Length;
int inChannelParameterCount = chord.InChannelParameters.Length;
int outChannelParameterCount = chord.OutChannelParameters.Length;
Type returnType = chord.ChordMethod.ReturnType;
ILGenerator generator = callback.GetILGenerator();
// IL: Get join channel
if (returnType != typeof(void))
{
generator.Emit(OpCodes.Ldarg_0);
generator.Emit(OpCodes.Ldfld, channelImplementer
.GetJoinChannelField(chord.ChordMethod.Name,
returnType));
}
// IL: Receive from Bus and store array
generator.DeclareLocal(typeof(object[]));
generator.Emit(OpCodes.Ldarg_1);
generator.EmitCall(OpCodes.Call, typeof (Bus).GetMethod("Receive", new Type[] {}), null);
generator.Emit(OpCodes.Stloc_0);
generator.Emit(OpCodes.Ldarg_0);
// IL: Reregister bus
generator.Emit(OpCodes.Ldarg_1);
generator.Emit(OpCodes.Ldarg_0);
generator.Emit(OpCodes.Ldftn, callback);
generator.Emit(OpCodes.Newobj, typeof(WaitOrTimerCallback).GetConstructor(new Type[] { typeof(object), typeof(IntPtr) }));
generator.EmitCall(OpCodes.Call, typeof(ChordManager).GetMethod("RegisterBus", new Type[] { typeof(Bus), typeof(WaitOrTimerCallback) }), null);
// IL: Unwrap value array
for (int parameterIndex = 0; parameterIndex < joinParameterCount; parameterIndex++)
{
generator.Emit(OpCodes.Ldloc_0);
generator.Emit(OpCodes.Ldc_I4, parameterIndex);
generator.Emit(OpCodes.Ldelem_Ref);
if (chord.JoinParameters[parameterIndex].ParameterType.IsValueType)
generator.Emit(OpCodes.Unbox_Any, chord.JoinParameters[parameterIndex].ParameterType);
}
for (int parameterIndex = 0; parameterIndex < inChannelParameterCount; parameterIndex++)
{
generator.Emit(OpCodes.Ldloc_0);
generator.Emit(OpCodes.Ldc_I4, parameterIndex + joinParameterCount);
generator.Emit(OpCodes.Ldelem_Ref);
if (chord.InChannelParameters[parameterIndex].ParameterType.IsValueType)
generator.Emit(OpCodes.Unbox_Any, chord.InChannelParameters[parameterIndex].ParameterType);
}
// IL: Prepare out channels
for (int channelParameterIndex = 0; channelParameterIndex < outChannelParameterCount; channelParameterIndex++)
{
generator.DeclareLocal(chord.OutChannelParameters[channelParameterIndex].ParameterType.GetElementType());
generator.Emit(OpCodes.Ldloca, channelParameterIndex + 1);
}
// IL: Call chord method
generator.EmitCall(OpCodes.Call, chord.ChordMethod, null);
// IL: Send result to join channel
if (returnType != typeof(void))
{
generator.EmitCall(OpCodes.Call, typeof(Channel<>)
.MakeGenericType(new Type[] { returnType })
.GetMethod("Send"), null);
}
// IL: Handle out channel results
for (int channelParameterIndex = 0; channelParameterIndex < outChannelParameterCount; channelParameterIndex++)
{
Type channelType = chord.OutChannelParameters[channelParameterIndex]
.ParameterType.GetElementType();
generator.Emit(OpCodes.Ldarg_0);
generator.Emit(OpCodes.Ldfld, channelImplementer
.GetChannelField(chord.OutChannelNames[channelParameterIndex],
channelType));
generator.Emit(OpCodes.Ldloc, channelParameterIndex + 1);
generator.EmitCall(OpCodes.Call, typeof(Channel<>)
.MakeGenericType(new Type[] { channelType })
.GetMethod("Send"), null);
}
generator.Emit(OpCodes.Ret);
callbacks.Add(chord, callback);
}
public void Implement(ChordInfo chord)
{
ImplementCallback(chord);
}
