Initial release
This commit is contained in:
civ
@@ -0,0 +1,263 @@
|
||||
//------------------------------------------------------------------------
|
||||
// Project : VST SDK
|
||||
//
|
||||
// Category : Helpers
|
||||
// Filename : public.sdk/source/vst/utility/objcclassbuilder.h
|
||||
// Created by : Steinberg, 06/2022
|
||||
// Description : Objective-C class builder utilities
|
||||
//
|
||||
//-----------------------------------------------------------------------------
|
||||
// This file is part of a Steinberg SDK. It is subject to the license terms
|
||||
// in the LICENSE file found in the top-level directory of this distribution
|
||||
// and at www.steinberg.net/sdklicenses.
|
||||
// No part of the SDK, including this file, may be copied, modified, propagated,
|
||||
// or distributed except according to the terms contained in the LICENSE file.
|
||||
//-----------------------------------------------------------------------------
|
||||
|
||||
#pragma once
|
||||
|
||||
#include <objc/runtime.h>
|
||||
#include <objc/message.h>
|
||||
#include <tuple>
|
||||
#include <string>
|
||||
#include <optional>
|
||||
#include <cmath>
|
||||
#include <cassert>
|
||||
|
||||
//------------------------------------------------------------------------------------
|
||||
namespace Steinberg {
|
||||
|
||||
//------------------------------------------------------------------------------------
|
||||
template<typename T>
|
||||
struct ObjCVariable
|
||||
{
|
||||
ObjCVariable (__unsafe_unretained id obj, Ivar ivar) : obj (obj), ivar (ivar) {}
|
||||
ObjCVariable (ObjCVariable&& o) { *this = std::move (o); }
|
||||
|
||||
ObjCVariable& operator= (ObjCVariable&& o)
|
||||
{
|
||||
obj = o.obj;
|
||||
ivar = o.ivar;
|
||||
o.obj = nullptr;
|
||||
o.ivar = nullptr;
|
||||
return *this;
|
||||
}
|
||||
|
||||
T get () const
|
||||
{
|
||||
auto offset = ivar_getOffset (ivar);
|
||||
return *reinterpret_cast<T*> (((__bridge uintptr_t)obj) + offset);
|
||||
}
|
||||
|
||||
void set (const T& value)
|
||||
{
|
||||
auto offset = ivar_getOffset (ivar);
|
||||
auto storage = reinterpret_cast<T*> (((__bridge uintptr_t)obj) + offset);
|
||||
*storage = value;
|
||||
}
|
||||
|
||||
private:
|
||||
__unsafe_unretained id obj;
|
||||
Ivar ivar {nullptr};
|
||||
};
|
||||
|
||||
//------------------------------------------------------------------------------------
|
||||
struct ObjCInstance
|
||||
{
|
||||
ObjCInstance (__unsafe_unretained id obj, Class superClass = nullptr) : obj (obj)
|
||||
{
|
||||
os.super_class = superClass;
|
||||
}
|
||||
|
||||
template<typename T>
|
||||
std::optional<ObjCVariable<T>> getVariable (const char* name) const
|
||||
{
|
||||
if (__strong auto ivar = class_getInstanceVariable (object_getClass (obj), name))
|
||||
{
|
||||
return {ObjCVariable<T> (obj, ivar)};
|
||||
}
|
||||
return {};
|
||||
}
|
||||
|
||||
template<typename Func, typename... T>
|
||||
void callSuper (SEL selector, T... args) const
|
||||
{
|
||||
void (*f) (__unsafe_unretained id, SEL, T...) =
|
||||
(void (*) (__unsafe_unretained id, SEL, T...))objc_msgSendSuper;
|
||||
f (getSuper (), selector, args...);
|
||||
}
|
||||
|
||||
template<typename Func, typename R, typename... T>
|
||||
R callSuper (SEL selector, T... args) const
|
||||
{
|
||||
R (*f)
|
||||
(__unsafe_unretained id, SEL, T...) =
|
||||
(R (*) (__unsafe_unretained id, SEL, T...))objc_msgSendSuper;
|
||||
return f (getSuper (), selector, args...);
|
||||
}
|
||||
|
||||
private:
|
||||
id getSuper () const
|
||||
{
|
||||
if (os.receiver == nullptr)
|
||||
{
|
||||
os.receiver = obj;
|
||||
}
|
||||
if (os.super_class == nullptr)
|
||||
{
|
||||
os.super_class = class_getSuperclass (object_getClass (obj));
|
||||
}
|
||||
return (__bridge id) (&os);
|
||||
}
|
||||
|
||||
__unsafe_unretained id obj;
|
||||
mutable objc_super os {};
|
||||
};
|
||||
|
||||
//------------------------------------------------------------------------------------
|
||||
struct ObjCClassBuilder
|
||||
{
|
||||
ObjCClassBuilder& init (const char* name, Class baseClass);
|
||||
|
||||
template<typename Func>
|
||||
ObjCClassBuilder& addMethod (SEL selector, Func imp);
|
||||
template<typename T>
|
||||
ObjCClassBuilder& addIvar (const char* name);
|
||||
|
||||
ObjCClassBuilder& addProtocol (const char* name);
|
||||
ObjCClassBuilder& addProtocol (Protocol* proto);
|
||||
|
||||
Class finalize ();
|
||||
|
||||
private:
|
||||
static Class generateUniqueClass (const std::string& inClassName, Class baseClass);
|
||||
|
||||
template<typename Func>
|
||||
ObjCClassBuilder& addMethod (SEL selector, Func imp, const char* types);
|
||||
|
||||
ObjCClassBuilder& addIvar (const char* name, size_t size, uint8_t alignment, const char* types);
|
||||
|
||||
template<typename R, typename... T>
|
||||
static constexpr std::tuple<R, T...> functionArgs (R (*) (T...))
|
||||
{
|
||||
return std::tuple<R, T...> ();
|
||||
}
|
||||
|
||||
template<typename... T>
|
||||
static constexpr std::tuple<T...> functionArgs (void (*) (T...))
|
||||
{
|
||||
return std::tuple<T...> ();
|
||||
}
|
||||
|
||||
template<typename R, typename... T>
|
||||
static constexpr bool isVoidReturnType (R (*) (T...))
|
||||
{
|
||||
return false;
|
||||
}
|
||||
|
||||
template<typename... T>
|
||||
static constexpr bool isVoidReturnType (void (*) (T...))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
template<typename Proc>
|
||||
static std::string encodeFunction (Proc proc)
|
||||
{
|
||||
std::string result;
|
||||
if (isVoidReturnType (proc))
|
||||
result = "v";
|
||||
std::apply ([&] (auto&&... args) { ((result += @encode (decltype (args))), ...); },
|
||||
functionArgs (proc));
|
||||
return result;
|
||||
}
|
||||
|
||||
Class cl {nullptr};
|
||||
Class baseClass {nullptr};
|
||||
};
|
||||
|
||||
//------------------------------------------------------------------------
|
||||
inline ObjCClassBuilder& ObjCClassBuilder::init (const char* name, Class bc)
|
||||
{
|
||||
baseClass = bc;
|
||||
cl = generateUniqueClass (name, baseClass);
|
||||
return *this;
|
||||
}
|
||||
|
||||
//------------------------------------------------------------------------------------
|
||||
inline Class ObjCClassBuilder::generateUniqueClass (const std::string& inClassName, Class baseClass)
|
||||
{
|
||||
std::string className (inClassName);
|
||||
int32_t iteration = 0;
|
||||
while (objc_lookUpClass (className.data ()) != nil)
|
||||
{
|
||||
iteration++;
|
||||
className = inClassName + "_" + std::to_string (iteration);
|
||||
}
|
||||
Class resClass = objc_allocateClassPair (baseClass, className.data (), 0);
|
||||
return resClass;
|
||||
}
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
inline Class ObjCClassBuilder::finalize ()
|
||||
{
|
||||
objc_registerClassPair (cl);
|
||||
|
||||
auto res = cl;
|
||||
baseClass = cl = nullptr;
|
||||
return res;
|
||||
}
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
template<typename Func>
|
||||
inline ObjCClassBuilder& ObjCClassBuilder::addMethod (SEL selector, Func imp, const char* types)
|
||||
{
|
||||
auto res = class_addMethod (cl, selector, IMP (imp), types);
|
||||
assert (res == true);
|
||||
(void)res;
|
||||
return *this;
|
||||
}
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
template<typename Func>
|
||||
ObjCClassBuilder& ObjCClassBuilder::addMethod (SEL selector, Func imp)
|
||||
{
|
||||
return addMethod (selector, imp, encodeFunction (imp).data ());
|
||||
}
|
||||
|
||||
//------------------------------------------------------------------------
|
||||
template<typename T>
|
||||
inline ObjCClassBuilder& ObjCClassBuilder::addIvar (const char* name)
|
||||
{
|
||||
return addIvar (name, sizeof (T), static_cast<uint8_t> (std::log2 (sizeof (T))), @encode (T));
|
||||
}
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
inline ObjCClassBuilder& ObjCClassBuilder::addIvar (const char* name, size_t size,
|
||||
uint8_t alignment, const char* types)
|
||||
{
|
||||
auto res = class_addIvar (cl, name, size, alignment, types);
|
||||
assert (res == true);
|
||||
(void)res;
|
||||
return *this;
|
||||
}
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
inline ObjCClassBuilder& ObjCClassBuilder::addProtocol (const char* name)
|
||||
{
|
||||
if (auto protocol = objc_getProtocol (name))
|
||||
return addProtocol (protocol);
|
||||
return *this;
|
||||
}
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
inline ObjCClassBuilder& ObjCClassBuilder::addProtocol (Protocol* proto)
|
||||
{
|
||||
auto res = class_addProtocol (cl, proto);
|
||||
assert (res == true);
|
||||
(void)res;
|
||||
return *this;
|
||||
}
|
||||
|
||||
//------------------------------------------------------------------------------------
|
||||
} // Steinberg
|
||||
Reference in New Issue
Block a user