sol2/sol/function.hpp
PrincessNyanara 3306b44162 okay std::function returns work
i want to use an is_function trait to differentiate classes when they get pushed
problem i feel that is_function may capture things not necessarily intended to be function objects
right now it is only qualified by pusher<function_t>
if change is necessary, then it becomes pusher<T, EnableIf<IsFunction<T>>>
2014-06-09 06:29:00 -04:00

236 lines
9.1 KiB
C++

// The MIT License (MIT)
// Copyright (c) 2013 Danny Y., Rapptz
// Permission is hereby granted, free of charge, to any person obtaining a copy of
// this software and associated documentation files (the "Software"), to deal in
// the Software without restriction, including without limitation the rights to
// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
// the Software, and to permit persons to whom the Software is furnished to do so,
// subject to the following conditions:
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
// IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#ifndef SOL_FUNCTION_HPP
#define SOL_FUNCTION_HPP
#include "reference.hpp"
#include "tuple.hpp"
#include "stack.hpp"
#include "function_types.hpp"
#include "userdata_traits.hpp"
#include <cstdint>
#include <functional>
#include <memory>
namespace sol {
class function : public reference {
private:
void luacall (std::size_t argcount, std::size_t resultcount) const {
lua_call(state(), static_cast<uint32_t>(argcount), static_cast<uint32_t>(resultcount));
}
template<typename... Ret>
std::tuple<Ret...> invoke(types<Ret...>, std::size_t n) const {
luacall(n, sizeof...(Ret));
return stack::pop_reverse_call(state(), std::make_tuple<Ret...>, types<Ret...>());
}
template<typename Ret>
Ret invoke(types<Ret>, std::size_t n) const {
luacall(n, 1);
return stack::pop<Ret>(state());
}
void invoke(types<void>, std::size_t n) const {
luacall(n, 0);
}
void invoke(types<>, std::size_t n) const {
luacall(n, 0);
}
public:
function() : reference() {}
function(lua_State* L, int index = -1): reference(L, index) {
type_assert(L, index, type::function);
}
function(const function&) = default;
function& operator=(const function&) = default;
template<typename... Args>
void operator()(Args&&... args) const {
call<>(std::forward<Args>(args)...);
}
template<typename... Ret, typename... Args>
typename return_type<Ret...>::type operator()(types<Ret...>, Args&&... args) const {
return call<Ret...>(std::forward<Args>(args)...);
}
template<typename... Ret, typename... Args>
typename return_type<Ret...>::type call(Args&&... args) const {
push();
stack::push(state(), std::forward<Args>(args)...);
return invoke(types<Ret...>(), sizeof...(Args));
}
};
namespace stack {
template <>
struct pusher<function_t> {
template<typename TFx>
static void set_isfunction_fx(std::true_type, lua_State* L, TFx&& fx) {
set_fx(std::false_type(), L, std::forward<TFx>(fx));
}
template<typename TFx>
static void set_isfunction_fx(std::false_type, lua_State* L, TFx&& fx) {
typedef Decay<TFx> clean_lambda;
typedef typename function_traits<decltype(&clean_lambda::operator())>::free_function_pointer_type raw_func_t;
typedef std::is_convertible<clean_lambda, raw_func_t> is_convertible;
set_isconvertible_fx(is_convertible(), L, std::forward<TFx>(fx));
}
template<typename TFx>
static void set_isconvertible_fx(std::true_type, lua_State* L, TFx&& fx) {
typedef Decay<TFx> clean_lambda;
typedef typename function_traits<decltype(&clean_lambda::operator())>::free_function_pointer_type raw_func_t;
set_isfunction_fx(std::true_type(), L, raw_func_t(std::forward<TFx>(fx)));
}
template<typename TFx>
static void set_isconvertible_fx(std::false_type, lua_State* L, TFx&& fx) {
typedef typename std::remove_pointer<Decay<TFx>>::type clean_fx;
std::unique_ptr<base_function> sptr(new functor_function<clean_fx>(std::forward<TFx>(fx)));
set_fx<TFx>(L, std::move(sptr));
}
template<typename TFx, typename TObj>
static void set_lvalue_fx(std::true_type, lua_State* L, TFx&& fx, TObj&& obj) {
set_fx(std::true_type(), L, std::forward<TFx>(fx), std::forward<TObj>(obj));
}
template<typename TFx, typename TObj>
static void set_lvalue_fx(std::false_type, lua_State* L, TFx&& fx, TObj&& obj) {
typedef typename std::remove_pointer<Decay<TFx>>::type clean_fx;
std::unique_ptr<base_function> sptr(new member_function<clean_fx, TObj>(std::forward<TObj>(obj), std::forward<TFx>(fx)));
return set_fx<TFx>(L, std::move(sptr));
}
template<typename TFx, typename TObj>
static void set_fx(std::true_type, lua_State* L, TFx&& fx, TObj&& obj) {
// Layout:
// idx 1...n: verbatim data of member function pointer
// idx n + 1: is the object's void pointer
// We don't need to store the size, because the other side is templated
// with the same member function pointer type
Decay<TFx> fxptr(std::forward<TFx>(fx));
void* userobjdata = static_cast<void*>(sol::detail::get_ptr(obj));
lua_CFunction freefunc = &static_member_function<Decay<TObj>, TFx>::call;
int upvalues = stack::detail::push_as_upvalues(L, fxptr);
stack::push(L, userobjdata);
stack::pusher<lua_CFunction>{}.push(L, freefunc, upvalues);
}
template<typename TFx>
static void set_fx(lua_State* L, std::false_type, TFx&& fx) {
Decay<TFx> target(std::forward<TFx>(fx));
lua_CFunction freefunc = &static_function<TFx>::call;
int upvalues = stack::detail::push_as_upvalues(L, target);
stack::pusher<lua_CFunction>{}.push(L, freefunc, upvalues);
}
template<typename TFx>
static void set_fx(lua_State* L, std::unique_ptr<base_function> luafunc) {
auto&& metakey = userdata_traits<Unqualified<TFx>>::metatable;
const char* metatablename = std::addressof(metakey[0]);
base_function* target = luafunc.release();
void* userdata = reinterpret_cast<void*>(target);
lua_CFunction freefunc = &base_function::call;
if (luaL_newmetatable(L, metatablename) == 1) {
lua_pushstring(L, "__gc");
stack::push(L, &base_function::gc);
lua_settable(L, -3);
}
stack::detail::push_userdata(L, userdata, metatablename);
stack::pusher<lua_CFunction>{}.push(L, freefunc, 1);
}
template<typename TFx>
static void set_function(lua_State* L, TFx&& fx) {
typedef typename std::remove_pointer<Decay<TFx>>::type clean_fx;
set_isfunction_fx(std::is_function<clean_fx>(), L, std::forward<TFx>(fx));
}
template<typename TFx, typename TObj>
static void set_function(lua_State* L, TFx&& fx, TObj&& obj) {
set_lvalue_fx(Bool<std::is_lvalue_reference<TObj>::value || std::is_pointer<TObj>::value>(),
L, std::forward<TFx>(fx), std::forward<TObj>(obj));
}
template <typename... Args>
static void push(lua_State* L, Args&&... args) {
set_function(L, std::forward<Args>(args)...);
}
};
template <typename Signature>
struct pusher<std::function<Signature>> {
static void push(lua_State* L, std::function<Signature> fx) {
pusher<function_t>{}.push(L, std::move(fx));
}
};
template <typename Signature>
struct getter<std::function<Signature>> {
typedef function_traits<Signature> fx_t;
typedef typename fx_t::args_type args_t;
typedef typename tuple_types<typename fx_t::return_type>::type ret_t;
template <typename... FxArgs, typename... Ret>
static std::function<Signature> get_std_func(types<FxArgs...>, types<Ret...>, lua_State* L, int index = -1) {
typedef typename function_traits<Signature>::return_type return_t;
sol::function f(L, index);
auto fx = [ f, L, index ] (FxArgs&&... args) -> return_t {
return f(types<Ret...>(), std::forward<FxArgs>(args)...);
};
return std::move(fx);
}
template <typename... FxArgs>
static std::function<Signature> get_std_func(types<FxArgs...>, types<void>, lua_State* L, int index = -1) {
sol::function f(L, index);
auto fx = [ f, L, index ] (FxArgs&&... args) -> void {
f(std::forward<FxArgs>(args)...);
};
return std::move(fx);
}
template <typename... FxArgs>
static std::function<Signature> get_std_func(types<FxArgs...> t, types<>, lua_State* L, int index = -1) {
return get_std_func(std::move(t), types<void>(), L, index);
}
static std::function<Signature> get(lua_State* L, int index) {
return get_std_func(args_t(), ret_t(), L, index);
}
};
} // stack
} // sol
#endif // SOL_FUNCTION_HPP