sol2/include/sol/metatable.hpp
ThePhD 57d9a05f88
🎨 Refactor tutorial examples
- 🛠 Make sure the tutorials compile across platforms!
- ✍ Redo quite a bit of the documentation
2021-03-06 10:14:48 -05:00

204 lines
8.0 KiB
C++

// sol2
// The MIT License (MIT)
// Copyright (c) 2013-2021 Rapptz, ThePhD and contributors
// 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_METATABLE_HPP
#define SOL_METATABLE_HPP
#include <sol/table_core.hpp>
#include <sol/usertype.hpp>
namespace sol {
template <typename base_type>
class basic_metatable : public basic_table<base_type> {
typedef basic_table<base_type> base_t;
friend class state;
friend class state_view;
protected:
basic_metatable(detail::no_safety_tag, lua_nil_t n) : base_t(n) {
}
basic_metatable(detail::no_safety_tag, lua_State* L, int index) : base_t(L, index) {
}
basic_metatable(detail::no_safety_tag, lua_State* L, ref_index index) : base_t(L, index) {
}
template <typename T,
meta::enable<meta::neg<meta::any_same<meta::unqualified_t<T>, basic_metatable>>, meta::neg<std::is_same<base_type, stack_reference>>,
meta::neg<std::is_same<lua_nil_t, meta::unqualified_t<T>>>, is_lua_reference<meta::unqualified_t<T>>> = meta::enabler>
basic_metatable(detail::no_safety_tag, T&& r) noexcept : base_t(std::forward<T>(r)) {
}
template <typename T, meta::enable<is_lua_reference<meta::unqualified_t<T>>> = meta::enabler>
basic_metatable(detail::no_safety_tag, lua_State* L, T&& r) noexcept : base_t(L, std::forward<T>(r)) {
}
template <typename R, typename... Args, typename Fx, typename Key, typename = std::invoke_result_t<Fx, Args...>>
void set_fx(types<R(Args...)>, Key&& key, Fx&& fx) {
set_resolved_function<R(Args...)>(std::forward<Key>(key), std::forward<Fx>(fx));
}
template <typename Fx, typename Key, meta::enable<meta::is_specialization_of<meta::unqualified_t<Fx>, overload_set>> = meta::enabler>
void set_fx(types<>, Key&& key, Fx&& fx) {
set(std::forward<Key>(key), std::forward<Fx>(fx));
}
template <typename Fx, typename Key, typename... Args,
meta::disable<meta::is_specialization_of<meta::unqualified_t<Fx>, overload_set>> = meta::enabler>
void set_fx(types<>, Key&& key, Fx&& fx, Args&&... args) {
set(std::forward<Key>(key), as_function_reference(std::forward<Fx>(fx), std::forward<Args>(args)...));
}
template <typename... Sig, typename... Args, typename Key>
void set_resolved_function(Key&& key, Args&&... args) {
set(std::forward<Key>(key), as_function_reference<function_sig<Sig...>>(std::forward<Args>(args)...));
}
public:
using base_t::lua_state;
basic_metatable() noexcept = default;
basic_metatable(const basic_metatable&) = default;
basic_metatable(basic_metatable&&) = default;
basic_metatable& operator=(const basic_metatable&) = default;
basic_metatable& operator=(basic_metatable&&) = default;
basic_metatable(const stack_reference& r) : basic_metatable(r.lua_state(), r.stack_index()) {
}
basic_metatable(stack_reference&& r) : basic_metatable(r.lua_state(), r.stack_index()) {
}
template <typename T, meta::enable_any<is_lua_reference<meta::unqualified_t<T>>> = meta::enabler>
basic_metatable(lua_State* L, T&& r) : base_t(L, std::forward<T>(r)) {
#if SOL_IS_ON(SOL_SAFE_REFERENCES_I_)
auto pp = stack::push_pop(*this);
constructor_handler handler {};
stack::check<basic_metatable>(lua_state(), -1, handler);
#endif // Safety
}
basic_metatable(lua_State* L, int index = -1) : basic_metatable(detail::no_safety, L, index) {
#if SOL_IS_ON(SOL_SAFE_REFERENCES_I_)
constructor_handler handler {};
stack::check<basic_metatable>(L, index, handler);
#endif // Safety
}
basic_metatable(lua_State* L, ref_index index) : basic_metatable(detail::no_safety, L, index) {
#if SOL_IS_ON(SOL_SAFE_REFERENCES_I_)
auto pp = stack::push_pop(*this);
constructor_handler handler {};
stack::check<basic_metatable>(lua_state(), -1, handler);
#endif // Safety
}
template <typename T,
meta::enable<meta::neg<meta::any_same<meta::unqualified_t<T>, basic_metatable>>, meta::neg<std::is_same<base_type, stack_reference>>,
meta::neg<std::is_same<lua_nil_t, meta::unqualified_t<T>>>, is_lua_reference<meta::unqualified_t<T>>> = meta::enabler>
basic_metatable(T&& r) noexcept : basic_metatable(detail::no_safety, std::forward<T>(r)) {
#if SOL_IS_ON(SOL_SAFE_REFERENCES_I_)
if (!is_table<meta::unqualified_t<T>>::value) {
auto pp = stack::push_pop(*this);
constructor_handler handler {};
stack::check<basic_metatable>(base_t::lua_state(), -1, handler);
}
#endif // Safety
}
basic_metatable(lua_nil_t r) noexcept : basic_metatable(detail::no_safety, r) {
}
template <typename Key, typename Value>
basic_metatable<base_type>& set(Key&& key, Value&& value);
template <typename Sig, typename Key, typename... Args>
basic_metatable& set_function(Key&& key, Args&&... args) {
set_fx(types<Sig>(), std::forward<Key>(key), std::forward<Args>(args)...);
return *this;
}
template <typename Key, typename... Args>
basic_metatable& set_function(Key&& key, Args&&... args) {
set_fx(types<>(), std::forward<Key>(key), std::forward<Args>(args)...);
return *this;
}
void unregister() {
using ustorage_base = u_detail::usertype_storage_base;
lua_State* L = this->lua_state();
auto pp = stack::push_pop(*this);
int top = lua_gettop(L);
stack_reference mt(L, -1);
stack::get_field(L, meta_function::gc_names, mt.stack_index());
if (type_of(L, -1) != type::table) {
lua_settop(L, top);
return;
}
stack_reference gc_names_table(L, -1);
stack::get_field(L, meta_function::storage, mt.stack_index());
if (type_of(L, -1) != type::lightuserdata) {
lua_settop(L, top);
return;
}
ustorage_base& base_storage = *static_cast<ustorage_base*>(stack::get<void*>(L, -1));
std::array<string_view, 6> registry_traits;
for (std::size_t i = 0; i < registry_traits.size(); ++i) {
u_detail::submetatable_type smt = static_cast<u_detail::submetatable_type>(i);
stack::get_field<false, true>(L, smt, gc_names_table.stack_index());
registry_traits[i] = stack::get<string_view>(L, -1);
}
// get the registry
stack_reference registry(L, raw_index(LUA_REGISTRYINDEX));
registry.push();
// eliminate all named entries for this usertype
// in the registry (luaL_newmetatable does
// [name] = new table
// in registry upon creation)
for (std::size_t i = 0; i < registry_traits.size(); ++i) {
u_detail::submetatable_type smt = static_cast<u_detail::submetatable_type>(i);
const string_view& gcmetakey = registry_traits[i];
if (smt == u_detail::submetatable_type::named) {
// use .data() to make it treat it like a c string,
// which it is...
stack::set_field<true>(L, gcmetakey.data(), lua_nil);
}
else {
// do not change the values in the registry: they need to be present
// no matter what, for safety's sake
// stack::set_field(L, gcmetakey, lua_nil, registry.stack_index());
}
}
// destroy all storage and tables
base_storage.clear();
// 6 strings from gc_names table,
// + 1 registry,
// + 1 gc_names table
// + 1 light userdata of storage
// + 1 registry
// 10 total, 4 left since popping off 6 gc_names tables
lua_settop(L, top);
}
};
} // namespace sol
#endif // SOL_METATABLE_HPP