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static private DefineType ( string name ) : |
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| name | string | |
| return | ||
/// <summary>
/// GetDispatcher is responsible for creating a class that provides
/// an appropriate managed callback method for a given delegate type.
/// </summary>
private Type GetDispatcher(Type dtype)
{
// If a dispatcher type for the given delegate type has already
// been generated, get it from the cache. The cache maps delegate
// types to generated dispatcher types. A possible optimization
// for the future would be to generate dispatcher types based on
// unique signatures rather than delegate types, since multiple
// delegate types with the same sig could use the same dispatcher.
object item = cache[dtype];
if (item != null)
{
return((Type)item);
}
string name = $"__{dtype.FullName}Dispatcher";
name = name.Replace('.', '_');
name = name.Replace('+', '_');
TypeBuilder tb = codeGenerator.DefineType(name, basetype);
// Generate a constructor for the generated type that calls the
// appropriate constructor of the Dispatcher base type.
MethodAttributes ma = MethodAttributes.Public |
MethodAttributes.HideBySig |
MethodAttributes.SpecialName |
MethodAttributes.RTSpecialName;
var cc = CallingConventions.Standard;
Type[] args = { ptrtype, typetype };
ConstructorBuilder cb = tb.DefineConstructor(ma, cc, args);
ConstructorInfo ci = basetype.GetConstructor(args);
ILGenerator il = cb.GetILGenerator();
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Ldarg_1);
il.Emit(OpCodes.Ldarg_2);
il.Emit(OpCodes.Call, ci);
il.Emit(OpCodes.Ret);
// Method generation: we generate a method named "Invoke" on the
// dispatcher type, whose signature matches the delegate type for
// which it is generated. The method body simply packages the
// arguments and hands them to the Dispatch() method, which deals
// with converting the arguments, calling the Python method and
// converting the result of the call.
MethodInfo method = dtype.GetMethod("Invoke");
ParameterInfo[] pi = method.GetParameters();
var signature = new Type[pi.Length];
for (var i = 0; i < pi.Length; i++)
{
signature[i] = pi[i].ParameterType;
}
MethodBuilder mb = tb.DefineMethod("Invoke", MethodAttributes.Public, method.ReturnType, signature);
ConstructorInfo ctor = listtype.GetConstructor(Type.EmptyTypes);
MethodInfo dispatch = basetype.GetMethod("Dispatch");
MethodInfo add = listtype.GetMethod("Add");
il = mb.GetILGenerator();
il.DeclareLocal(listtype);
il.Emit(OpCodes.Newobj, ctor);
il.Emit(OpCodes.Stloc_0);
for (var c = 0; c < signature.Length; c++)
{
Type t = signature[c];
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Ldarg_S, (byte)(c + 1));
if (t.IsValueType)
{
il.Emit(OpCodes.Box, t);
}
il.Emit(OpCodes.Callvirt, add);
il.Emit(OpCodes.Pop);
}
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Call, dispatch);
if (method.ReturnType == voidtype)
{
il.Emit(OpCodes.Pop);
}
else if (method.ReturnType.IsValueType)
{
il.Emit(OpCodes.Unbox_Any, method.ReturnType);
}
il.Emit(OpCodes.Ret);
Type disp = tb.CreateType();
cache[dtype] = disp;
return(disp);
}
/// <summary>
/// GetDispatcher is responsible for creating a class that provides
/// an appropriate managed callback method for a given delegate type.
/// </summary>
private Type GetDispatcher(Type dtype)
{
// If a dispatcher type for the given delegate type has already
// been generated, get it from the cache. The cache maps delegate
// types to generated dispatcher types. A possible optimization
// for the future would be to generate dispatcher types based on
// unique signatures rather than delegate types, since multiple
// delegate types with the same sig could use the same dispatcher.
if (cache.TryGetValue(dtype, out Type item))
{
return(item);
}
string name = $"__{dtype.FullName}Dispatcher";
name = name.Replace('.', '_');
name = name.Replace('+', '_');
TypeBuilder tb = codeGenerator.DefineType(name, basetype);
// Generate a constructor for the generated type that calls the
// appropriate constructor of the Dispatcher base type.
MethodAttributes ma = MethodAttributes.Public |
MethodAttributes.HideBySig |
MethodAttributes.SpecialName |
MethodAttributes.RTSpecialName;
var cc = CallingConventions.Standard;
Type[] args = { pyobjType, typetype };
ConstructorBuilder cb = tb.DefineConstructor(ma, cc, args);
ConstructorInfo ci = basetype.GetConstructor(BindingFlags.Instance | BindingFlags.NonPublic, null, args, null);
ILGenerator il = cb.GetILGenerator();
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Ldarg_1);
il.Emit(OpCodes.Ldarg_2);
il.Emit(OpCodes.Call, ci);
il.Emit(OpCodes.Ret);
// Method generation: we generate a method named "Invoke" on the
// dispatcher type, whose signature matches the delegate type for
// which it is generated. The method body simply packages the
// arguments and hands them to the Dispatch() method, which deals
// with converting the arguments, calling the Python method and
// converting the result of the call.
MethodInfo method = dtype.GetMethod("Invoke");
ParameterInfo[] pi = method.GetParameters();
var signature = new Type[pi.Length];
for (var i = 0; i < pi.Length; i++)
{
signature[i] = pi[i].ParameterType;
}
MethodBuilder mb = tb.DefineMethod("Invoke", MethodAttributes.Public, method.ReturnType, signature);
il = mb.GetILGenerator();
// loc_0 = new object[pi.Length]
il.DeclareLocal(arrayType);
il.Emit(OpCodes.Ldc_I4, pi.Length);
il.Emit(OpCodes.Newobj, arrayCtor);
il.Emit(OpCodes.Stloc_0);
bool anyByRef = false;
for (var c = 0; c < signature.Length; c++)
{
Type t = signature[c];
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Ldc_I4, c);
il.Emit(OpCodes.Ldarg_S, (byte)(c + 1));
if (t.IsByRef)
{
// The argument is a pointer. We must dereference the pointer to get the value or object it points to.
t = t.GetElementType();
if (t.IsValueType)
{
il.Emit(OpCodes.Ldobj, t);
}
else
{
il.Emit(OpCodes.Ldind_Ref);
}
anyByRef = true;
}
if (t.IsValueType)
{
il.Emit(OpCodes.Box, t);
}
// args[c] = arg
il.Emit(OpCodes.Stelem_Ref);
}
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Call, dispatch);
if (anyByRef)
{
// Dispatch() will have modified elements of the args list that correspond to out parameters.
CodeGenerator.GenerateMarshalByRefsBack(il, signature);
}
if (method.ReturnType == voidtype)
{
il.Emit(OpCodes.Pop);
}
else if (method.ReturnType.IsValueType)
{
il.Emit(OpCodes.Unbox_Any, method.ReturnType);
}
il.Emit(OpCodes.Ret);
Type disp = tb.CreateType();
cache[dtype] = disp;
return(disp);
}