sol2/sol/usertype.hpp
ThePhD 184f16d7fa Updated copyright headers and added compatibility with lua 5.1.5 and luajit!
This means sol can now run on the fastest dynamic language implementation ever!
Wooo!~
2015-05-24 21:29:21 -04:00

420 lines
17 KiB
C++

// The MIT License (MIT)
// Copyright (c) 2013-2015 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_USERTYPE_HPP
#define SOL_USERTYPE_HPP
#include "state.hpp"
#include "function_types.hpp"
#include "usertype_traits.hpp"
#include "default_construct.hpp"
#include "deprecate.hpp"
#include <vector>
#include <array>
#include <algorithm>
namespace sol {
namespace detail {
template<typename T, typename... Args>
inline std::unique_ptr<T> make_unique(Args&&... args) {
return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
}
} // detail
const std::array<std::string, 2> meta_variable_names = {{
"__index",
"__newindex"
}};
const std::array<std::string, 19> meta_function_names = {{
"__index",
"__newindex",
"__mode",
"__call",
"__metatable",
"__tostring",
"__len",
"__unm",
"__add",
"__sub",
"__mul",
"__div",
"__mod",
"__pow",
"__concat",
"__eq",
"__lt",
"__le",
"__gc",
}};
enum class meta_function {
index,
new_index,
mode,
call,
metatable,
to_string,
length,
unary_minus,
addition,
subtraction,
multiplication,
division,
modulus,
power_of,
involution = power_of,
concatenation,
equal_to,
less_than,
less_than_or_equal_to,
};
template<typename T>
class usertype {
private:
typedef std::unordered_map<std::string, std::pair<std::unique_ptr<base_function>, bool>> function_map_t;
function_map_t indexmetafunctions, newindexmetafunctions;
std::vector<std::string> functionnames;
std::vector<std::unique_ptr<base_function>> metafunctions;
std::vector<luaL_Reg> metafunctiontable;
std::vector<luaL_Reg> ptrmetafunctiontable;
lua_CFunction cleanup;
template<typename... TTypes>
struct constructor {
template<typename... Args>
static void do_constructor(lua_State* L, T* obj, call_syntax syntax, int, types<Args...>) {
default_construct fx{};
stack::call(L, -1 + static_cast<int>(syntax), types<void>(), types<Args...>(), fx, obj);
}
static void match_constructor(lua_State*, T*, call_syntax, int) {
throw error("No matching constructor for the arguments provided");
}
template<typename ...CArgs, typename... Args>
static void match_constructor(lua_State* L, T* obj, call_syntax syntax, int argcount, types<CArgs...> t, Args&&... args) {
if(argcount == sizeof...(CArgs)) {
do_constructor(L, obj, syntax, argcount, t);
return;
}
match_constructor(L, obj, syntax, argcount, std::forward<Args>(args)...);
}
static int construct(lua_State* L) {
auto&& meta = usertype_traits<T>::metatable;
call_syntax syntax = stack::get_call_syntax(L, meta);
int argcount = lua_gettop(L);
void* udata = lua_newuserdata(L, sizeof(T));
T* obj = static_cast<T*>(udata);
match_constructor(L, obj, syntax, argcount - static_cast<int>(syntax), typename identity<TTypes>::type()...);
if(luaL_newmetatable(L, std::addressof(meta[0])) == 1) {
lua_pop(L, 1);
std::string err = "Unable to get usertype metatable for ";
err += meta;
throw error(err);
}
lua_setmetatable(L, -2);
return 1;
}
};
struct destructor {
static int destruct(lua_State* L) {
userdata udata = stack::get<userdata>(L, 1);
T* obj = static_cast<T*>(udata.value);
std::allocator<T> alloc{};
alloc.destroy(obj);
return 0;
}
};
template<std::size_t N>
void build_cleanup() {
cleanup = &base_function::usertype<N>::gc;
}
template<std::size_t N>
void build_function_tables(function_map_t*& index, function_map_t*& newindex) {
int extracount = 0;
if(!indexmetafunctions.empty()) {
if(index == nullptr) {
auto idxptr = detail::make_unique<usertype_indexing_function<void (T::*)(), T>>("__index", nullptr);
index = &(idxptr->functions);
functionnames.emplace_back("__index");
metafunctions.emplace_back(std::move(idxptr));
std::string& name = functionnames.back();
metafunctiontable.push_back({ name.c_str(), &base_function::usertype<N>::call });
ptrmetafunctiontable.push_back({ name.c_str(), &base_function::usertype<N>::ref_call });
++extracount;
}
auto& idx = *index;
for(auto&& namedfunc : indexmetafunctions) {
idx.emplace(std::move(namedfunc.first), std::move(namedfunc.second));
}
}
if(!newindexmetafunctions.empty()) {
if(newindex == nullptr) {
auto idxptr = detail::make_unique<usertype_indexing_function<void (T::*)(), T>>("__newindex", nullptr);
newindex = &(idxptr->functions);
functionnames.emplace_back("__newindex");
metafunctions.emplace_back(std::move(idxptr));
std::string& name = functionnames.back();
if(extracount > 0) {
metafunctiontable.push_back({ name.c_str(), &base_function::usertype<N + 1>::call });
ptrmetafunctiontable.push_back({ name.c_str(), &base_function::usertype<N + 1>::ref_call });
}
else {
metafunctiontable.push_back({ name.c_str(), &base_function::usertype<N>::call });
ptrmetafunctiontable.push_back({ name.c_str(), &base_function::usertype<N>::ref_call });
}
++extracount;
}
auto& idx = *newindex;
for(auto&& namedfunc : newindexmetafunctions) {
idx.emplace(std::move(namedfunc.first), std::move(namedfunc.second));
}
}
switch(extracount) {
case 2:
build_cleanup<N + 2>();
break;
case 1:
build_cleanup<N + 1>();
break;
case 0:
default:
build_cleanup<N + 0>();
break;
}
}
template<std::size_t N, typename Base, typename Ret>
bool build_function(std::true_type, function_map_t*&, function_map_t*&, std::string funcname, Ret Base::* func) {
static_assert(std::is_base_of<Base, T>::value, "Any registered function must be part of the class");
typedef typename std::decay<decltype(func)>::type function_type;
indexmetafunctions.emplace(funcname, std::make_pair(detail::make_unique<usertype_variable_function<function_type, T>>(func), false));
newindexmetafunctions.emplace(funcname, std::make_pair(detail::make_unique<usertype_variable_function<function_type, T>>(func), false));
return false;
}
template<typename Arg, typename... Args, typename Ret>
std::unique_ptr<base_function> make_function(const std::string&, Ret(*func)(Arg, Args...)) {
typedef Unqualified<Arg> Argu;
static_assert(std::is_base_of<Argu, T>::value, "Any non-member-function must have a first argument which is covariant with the desired userdata type.");
typedef typename std::decay<decltype(func)>::type function_type;
return detail::make_unique<usertype_function<function_type, T>>(func);
}
template<typename Base, typename Ret>
std::unique_ptr<base_function> make_variable_function(std::true_type, const std::string&, Ret Base::* func) {
static_assert(std::is_base_of<Base, T>::value, "Any registered function must be part of the class");
typedef typename std::decay<decltype(func)>::type function_type;
return detail::make_unique<usertype_variable_function<function_type, T>>(func);
}
template<typename Base, typename Ret>
std::unique_ptr<base_function> make_variable_function(std::false_type, const std::string&, Ret Base::* func) {
static_assert(std::is_base_of<Base, T>::value, "Any registered function must be part of the class");
typedef typename std::decay<decltype(func)>::type function_type;
return detail::make_unique<usertype_function<function_type, T>>(func);
}
template<typename Base, typename Ret>
std::unique_ptr<base_function> make_function(const std::string& name, Ret Base::* func) {
typedef typename std::decay<decltype(func)>::type function_type;
return make_variable_function(std::is_member_object_pointer<function_type>(), name, func);
}
template<typename Fx>
std::unique_ptr<base_function> make_function(const std::string&, Fx&& func) {
typedef Unqualified<Fx> Fxu;
typedef typename std::tuple_element<0, typename function_traits<Fxu>::arg_tuple_type>::type TArg;
typedef Unqualified<TArg> TArgu;
static_assert(std::is_base_of<TArgu, T>::value, "Any non-member-function must have a first argument which is covariant with the desired userdata type.");
typedef typename std::decay<decltype(func)>::type function_type;
return detail::make_unique<usertype_function<function_type, T>>(func);
}
template<std::size_t N, typename Fx>
bool build_function(std::false_type, function_map_t*& index, function_map_t*& newindex, std::string funcname, Fx&& func) {
typedef typename std::decay<Fx>::type function_type;
auto metamethod = std::find(meta_function_names.begin(), meta_function_names.end(), funcname);
if(metamethod != meta_function_names.end()) {
functionnames.push_back(std::move(funcname));
std::string& name = functionnames.back();
auto indexmetamethod = std::find(meta_variable_names.begin(), meta_variable_names.end(), name);
std::unique_ptr<base_function> ptr(nullptr);
if(indexmetamethod != meta_variable_names.end()) {
auto idxptr = detail::make_unique<usertype_indexing_function<function_type, T>>(name, func);
switch(std::distance(indexmetamethod, meta_variable_names.end())) {
case 0:
index = &(idxptr->functions);
break;
case 1:
newindex = &(idxptr->functions);
break;
default:
break;
}
ptr = std::move(idxptr);
}
else {
ptr = make_function(funcname, std::forward<Fx>(func));
}
metafunctions.emplace_back(std::move(ptr));
metafunctiontable.push_back( { name.c_str(), &base_function::usertype<N>::call } );
ptrmetafunctiontable.push_back( { name.c_str(), &base_function::usertype<N>::ref_call } );
return true;
}
indexmetafunctions.emplace(funcname, std::make_pair(make_function(funcname, std::forward<Fx>(func)), true));
return false;
}
template<std::size_t N, typename Fx, typename... Args>
void build_function_tables(function_map_t*& index, function_map_t*& newindex, std::string funcname, Fx&& func, Args&&... args) {
typedef typename std::is_member_object_pointer<Unqualified<Fx>>::type is_variable;
static const std::size_t V = static_cast<std::size_t>(!is_variable::value);
if(build_function<N>(is_variable(), index, newindex, std::move(funcname), std::forward<Fx>(func))) {
build_function_tables<N + V>(index, newindex, std::forward<Args>(args)...);
}
else {
build_function_tables<N>(index, newindex, std::forward<Args>(args)...);
}
}
template<std::size_t N, typename Base, typename Ret, typename... Args>
void build_function_tables(function_map_t*& index, function_map_t*& newindex, meta_function metafunc, Ret Base::* func, Args&&... args) {
std::size_t idx = static_cast<std::size_t>(metafunc);
const std::string& funcname = meta_function_names[idx];
build_function_tables<N>(index, newindex, funcname, std::move(func), std::forward<Args>(args)...);
}
public:
template<typename... Args>
usertype(Args&&... args): usertype(default_constructor, std::forward<Args>(args)...) {}
template<typename... Args>
SOL_DEPRECATED usertype(std::string, std::string, Args&&... args): usertype(default_constructor, std::forward<Args>(args)...) {}
template<typename... Args>
SOL_DEPRECATED usertype(const char*, std::string, Args&&... args): usertype(default_constructor, std::forward<Args>(args)...) {}
template<typename... Args, typename... CArgs>
SOL_DEPRECATED usertype(std::string, constructors<CArgs...> c, Args&&... args) : usertype(std::move(c), std::forward<Args>(args)...) {}
template<typename... Args, typename... CArgs>
SOL_DEPRECATED usertype(const char*, constructors<CArgs...> c, Args&&... args) : usertype(std::move(c), std::forward<Args>(args)...) {}
template<typename... Args, typename... CArgs>
usertype(constructors<CArgs...>, Args&&... args) {
functionnames.reserve(sizeof...(args) + 2);
metafunctiontable.reserve(sizeof...(args));
ptrmetafunctiontable.reserve(sizeof...(args));
function_map_t* index = nullptr;
function_map_t* newindex = nullptr;
build_function_tables<0>(index, newindex, std::forward<Args>(args)...);
indexmetafunctions.clear();
newindexmetafunctions.clear();
functionnames.push_back("new");
metafunctiontable.push_back({ functionnames.back().c_str(), &constructor<CArgs...>::construct });
functionnames.push_back("__gc");
metafunctiontable.push_back({ functionnames.back().c_str(), &destructor::destruct });
// ptr_functions does not participate in garbage collection/new,
// as all pointered types are considered
// to be references. This makes returns of
// `std::vector<int>&` and `std::vector<int>*` work
metafunctiontable.push_back({ nullptr, nullptr });
ptrmetafunctiontable.push_back({ nullptr, nullptr });
}
int push(lua_State* L) {
// push pointer tables first,
// but leave the regular T table on last
// so it can be linked to a type for usage with `.new(...)` or `:new(...)`
push_metatable(L, usertype_traits<T*>::metatable,
metafunctions, ptrmetafunctiontable);
lua_pop(L, 1);
push_metatable(L, usertype_traits<T>::metatable,
metafunctions, metafunctiontable);
set_global_deleter(L);
return 1;
}
private:
template<typename Meta, typename MetaFuncs, typename MetaFuncTable>
static void push_metatable(lua_State* L, Meta&& metakey, MetaFuncs&& metafuncs, MetaFuncTable&& metafunctable) {
luaL_newmetatable(L, std::addressof(metakey[0]));
if(metafunctable.size() > 1) {
// regular functions accessed through __index semantics
int up = push_upvalues(L, metafuncs);
luaL_setfuncs(L, metafunctable.data(), up);
}
}
void set_global_deleter(lua_State* L) {
// Automatic deleter table -- stays alive until lua VM dies
// even if the user calls collectgarbage()
lua_createtable(L, 0, 0);
lua_createtable(L, 0, 1);
int up = push_upvalues<true>(L, metafunctions);
lua_pushcclosure(L, cleanup, up);
lua_setfield(L, -2, "__gc");
lua_setmetatable(L, -2);
// gctable name by default has ♻ part of it
lua_setglobal(L, std::addressof(usertype_traits<T>::gctable[0]));
}
template<bool release = false, typename TCont>
static int push_upvalues(lua_State* L, TCont&& cont) {
int n = 0;
for(auto& c : cont) {
if(release) {
stack::push<upvalue>(L, c.release());
}
else {
stack::push<upvalue>(L, c.get());
}
++n;
}
return n;
}
};
namespace stack {
template<typename T>
struct pusher<usertype<T>> {
static int push(lua_State* L, usertype<T>& user) {
return user.push(L);
}
};
} // stack
} // sol
#endif // SOL_USERTYPE_HPP