sol2/sol/protected_function.hpp
2017-10-26 13:15:02 -04:00

358 lines
14 KiB
C++

// The MIT License (MIT)
// Copyright (c) 2013-2017 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_PROTECTED_FUNCTION_HPP
#define SOL_PROTECTED_FUNCTION_HPP
#include "reference.hpp"
#include "stack.hpp"
#include "protected_function_result.hpp"
#include "unsafe_function.hpp"
#include <cstdint>
#include <algorithm>
namespace sol {
namespace detail {
inline const char (&default_handler_name())[9] {
static const char name[9] = "sol.\xF0\x9F\x94\xA9";
return name;
}
template <bool b, typename target_t = reference>
struct protected_handler {
typedef is_stack_based<target_t> is_stack;
const target_t& target;
int stackindex;
protected_handler(std::false_type, const target_t& target)
: target(target), stackindex(0) {
if (b) {
stackindex = lua_gettop(target.lua_state()) + 1;
target.push();
}
}
protected_handler(std::true_type, const target_t& target)
: target(target), stackindex(0) {
if (b) {
stackindex = target.stack_index();
}
}
protected_handler(const target_t& target)
: protected_handler(is_stack(), target) {
}
bool valid() const noexcept {
return b;
}
~protected_handler() {
if (!is_stack::value && stackindex != 0) {
lua_remove(target.lua_state(), stackindex);
}
}
};
template <typename base_t, typename T>
basic_function<base_t> force_cast(T& p) {
return p;
}
} // namespace detail
template <typename base_t, bool aligned = false, typename handler_t = reference>
class basic_protected_function : public base_t {
public:
typedef is_stack_based<handler_t> is_stack_handler;
static handler_t get_default_handler(lua_State* L) {
if (is_stack_handler::value || L == nullptr)
return handler_t(L, lua_nil);
L = is_main_threaded<base_t>::value ? main_thread(L, L) : L;
lua_getglobal(L, detail::default_handler_name());
auto pp = stack::pop_n(L, 1);
return handler_t(L, -1);
}
template <typename T>
static void set_default_handler(const T& ref) {
if (ref.lua_state() == nullptr) {
return;
}
lua_State* L = ref.lua_state();
if (!ref.valid()) {
lua_pushnil(L);
lua_setglobal(L, detail::default_handler_name());
}
else {
ref.push();
lua_setglobal(L, detail::default_handler_name());
}
}
private:
template <bool b>
call_status luacall(std::ptrdiff_t argcount, std::ptrdiff_t resultcount, detail::protected_handler<b, handler_t>& h) const {
return static_cast<call_status>(lua_pcall(lua_state(), static_cast<int>(argcount), static_cast<int>(resultcount), h.stackindex));
}
template <std::size_t... I, bool b, typename... Ret>
auto invoke(types<Ret...>, std::index_sequence<I...>, std::ptrdiff_t n, detail::protected_handler<b, handler_t>& h) const {
luacall(n, sizeof...(Ret), h);
return stack::pop<std::tuple<Ret...>>(lua_state());
}
template <std::size_t I, bool b, typename Ret>
Ret invoke(types<Ret>, std::index_sequence<I>, std::ptrdiff_t n, detail::protected_handler<b, handler_t>& h) const {
luacall(n, 1, h);
return stack::pop<Ret>(lua_state());
}
template <std::size_t I, bool b>
void invoke(types<void>, std::index_sequence<I>, std::ptrdiff_t n, detail::protected_handler<b, handler_t>& h) const {
luacall(n, 0, h);
}
template <bool b>
protected_function_result invoke(types<>, std::index_sequence<>, std::ptrdiff_t n, detail::protected_handler<b, handler_t>& h) const {
int stacksize = lua_gettop(lua_state());
int poststacksize = stacksize;
int firstreturn = 1;
int returncount = 0;
call_status code = call_status::ok;
#ifndef SOL_NO_EXCEPTIONS
auto onexcept = [&](const char* error) {
h.stackindex = 0;
if (b) {
h.target.push();
stack::push(lua_state(), error);
lua_call(lua_state(), 1, 1);
}
else {
stack::push(lua_state(), error);
}
};
#if !defined(SOL_EXCEPTIONS_SAFE_PROPAGATION)
try {
#endif
#endif // No Exceptions
firstreturn = (std::max)(1, static_cast<int>(stacksize - n - static_cast<int>(h.valid())));
code = luacall(n, LUA_MULTRET, h);
poststacksize = lua_gettop(lua_state()) - static_cast<int>(h.valid());
returncount = poststacksize - (firstreturn - 1);
#ifndef SOL_NO_EXCEPTIONS
#if !defined(SOL_EXCEPTIONS_SAFE_PROPAGATION)
}
// Handle C++ errors thrown from C++ functions bound inside of lua
catch (const char* error) {
onexcept(error);
firstreturn = lua_gettop(lua_state());
return protected_function_result(lua_state(), firstreturn, 0, 1, call_status::runtime);
}
catch (const std::exception& error) {
onexcept(error.what());
firstreturn = lua_gettop(lua_state());
return protected_function_result(lua_state(), firstreturn, 0, 1, call_status::runtime);
}
catch (...) {
onexcept("caught (...) unknown error during protected_function call");
firstreturn = lua_gettop(lua_state());
return protected_function_result(lua_state(), firstreturn, 0, 1, call_status::runtime);
}
#else
// do not handle exceptions: they can be propogated into C++ and keep all type information / rich information
#endif // about as safe as possible
#endif // No Exceptions
return protected_function_result(lua_state(), firstreturn, returncount, returncount, code);
}
public:
using base_t::lua_state;
handler_t error_handler;
basic_protected_function() = default;
template <typename T, meta::enable<meta::neg<std::is_same<meta::unqualified_t<T>, basic_protected_function>>, meta::neg<std::is_base_of<proxy_base_tag, meta::unqualified_t<T>>>, meta::neg<std::is_same<base_t, stack_reference>>, is_lua_reference<meta::unqualified_t<T>>> = meta::enabler>
basic_protected_function(T&& r) noexcept
: base_t(std::forward<T>(r)), error_handler(get_default_handler(r.lua_state())) {
#ifdef SOL_CHECK_ARGUMENTS
if (!is_function<meta::unqualified_t<T>>::value) {
auto pp = stack::push_pop(*this);
constructor_handler handler{};
stack::check<basic_protected_function>(lua_state(), -1, handler);
}
#endif // Safety
}
basic_protected_function(const basic_protected_function&) = default;
basic_protected_function& operator=(const basic_protected_function&) = default;
basic_protected_function(basic_protected_function&&) = default;
basic_protected_function& operator=(basic_protected_function&&) = default;
basic_protected_function(const basic_function<base_t>& b)
: basic_protected_function(b, get_default_handler(b.lua_state())) {
}
basic_protected_function(basic_function<base_t>&& b)
: basic_protected_function(std::move(b), get_default_handler(b.lua_state())) {
}
basic_protected_function(const basic_function<base_t>& b, handler_t eh)
: base_t(b), error_handler(std::move(eh)) {
}
basic_protected_function(basic_function<base_t>&& b, handler_t eh)
: base_t(std::move(b)), error_handler(std::move(eh)) {
}
basic_protected_function(const stack_reference& r)
: basic_protected_function(r.lua_state(), r.stack_index(), get_default_handler(r.lua_state())) {
}
basic_protected_function(stack_reference&& r)
: basic_protected_function(r.lua_state(), r.stack_index(), get_default_handler(r.lua_state())) {
}
basic_protected_function(const stack_reference& r, handler_t eh)
: basic_protected_function(r.lua_state(), r.stack_index(), std::move(eh)) {
}
basic_protected_function(stack_reference&& r, handler_t eh)
: basic_protected_function(r.lua_state(), r.stack_index(), std::move(eh)) {
}
template <typename Super>
basic_protected_function(const proxy_base<Super>& p)
: basic_protected_function(p, get_default_handler(p.lua_state())) {
}
template <typename Super>
basic_protected_function(proxy_base<Super>&& p)
: basic_protected_function(std::move(p), get_default_handler(p.lua_state())) {
}
template <typename Proxy, typename Handler, meta::enable<std::is_base_of<proxy_base_tag, meta::unqualified_t<Proxy>>, meta::neg<is_lua_index<meta::unqualified_t<Handler>>>> = meta::enabler>
basic_protected_function(Proxy&& p, Handler&& eh)
: basic_protected_function(detail::force_cast<base_t>(p), std::forward<Handler>(eh)) {
}
template <typename T, meta::enable<is_lua_reference<meta::unqualified_t<T>>> = meta::enabler>
basic_protected_function(lua_State* L, T&& r)
: basic_protected_function(L, std::forward<T>(r), get_default_handler(L)) {
}
template <typename T, meta::enable<is_lua_reference<meta::unqualified_t<T>>> = meta::enabler>
basic_protected_function(lua_State* L, T&& r, handler_t eh)
: base_t(L, std::forward<T>(r)), error_handler(std::move(eh)) {
#ifdef SOL_CHECK_ARGUMENTS
auto pp = stack::push_pop(*this);
constructor_handler handler{};
stack::check<basic_protected_function>(lua_state(), -1, handler);
#endif // Safety
}
basic_protected_function(lua_State* L, int index = -1)
: basic_protected_function(L, index, get_default_handler(L)) {
}
basic_protected_function(lua_State* L, int index, handler_t eh)
: base_t(L, index), error_handler(std::move(eh)) {
#ifdef SOL_CHECK_ARGUMENTS
constructor_handler handler{};
stack::check<basic_protected_function>(L, index, handler);
#endif // Safety
}
basic_protected_function(lua_State* L, absolute_index index)
: basic_protected_function(L, index, get_default_handler(L)) {
}
basic_protected_function(lua_State* L, absolute_index index, handler_t eh)
: base_t(L, index), error_handler(std::move(eh)) {
#ifdef SOL_CHECK_ARGUMENTS
constructor_handler handler{};
stack::check<basic_protected_function>(L, index, handler);
#endif // Safety
}
basic_protected_function(lua_State* L, raw_index index)
: basic_protected_function(L, index, get_default_handler(L)) {
}
basic_protected_function(lua_State* L, raw_index index, handler_t eh)
: base_t(L, index), error_handler(std::move(eh)) {
#ifdef SOL_CHECK_ARGUMENTS
constructor_handler handler{};
stack::check<basic_protected_function>(L, index, handler);
#endif // Safety
}
basic_protected_function(lua_State* L, ref_index index)
: basic_protected_function(L, index, get_default_handler(L)) {
}
basic_protected_function(lua_State* L, ref_index index, handler_t eh)
: base_t(L, index), error_handler(std::move(eh)) {
#ifdef SOL_CHECK_ARGUMENTS
auto pp = stack::push_pop(*this);
constructor_handler handler{};
stack::check<basic_protected_function>(lua_state(), -1, handler);
#endif // Safety
}
template <typename... Args>
protected_function_result operator()(Args&&... args) const {
return call<>(std::forward<Args>(args)...);
}
template <typename... Ret, typename... Args>
decltype(auto) operator()(types<Ret...>, Args&&... args) const {
return call<Ret...>(std::forward<Args>(args)...);
}
template <typename... Ret, typename... Args>
decltype(auto) call(Args&&... args) const {
if (!aligned) {
// we do not expect the function to already be on the stack: push it
if (error_handler.valid()) {
detail::protected_handler<true, handler_t> h(error_handler);
base_t::push();
int pushcount = stack::multi_push_reference(lua_state(), std::forward<Args>(args)...);
return invoke(types<Ret...>(), std::make_index_sequence<sizeof...(Ret)>(), pushcount, h);
}
else {
detail::protected_handler<false, handler_t> h(error_handler);
base_t::push();
int pushcount = stack::multi_push_reference(lua_state(), std::forward<Args>(args)...);
return invoke(types<Ret...>(), std::make_index_sequence<sizeof...(Ret)>(), pushcount, h);
}
}
else {
// the function is already on the stack at the right location
if (error_handler.valid()) {
// the handler will be pushed onto the stack manually,
// since it's not already on the stack this means we need to push our own
// function on the stack too and swap things to be in-place
if (!is_stack_handler::value) {
// so, we need to remove the function at the top and then dump the handler out ourselves
base_t::push();
}
detail::protected_handler<true, handler_t> h(error_handler);
if (!is_stack_handler::value) {
lua_replace(lua_state(), -3);
h.stackindex = lua_absindex(lua_state(), -2);
}
int pushcount = stack::multi_push_reference(lua_state(), std::forward<Args>(args)...);
return invoke(types<Ret...>(), std::make_index_sequence<sizeof...(Ret)>(), pushcount, h);
}
else {
detail::protected_handler<false, handler_t> h(error_handler);
int pushcount = stack::multi_push_reference(lua_state(), std::forward<Args>(args)...);
return invoke(types<Ret...>(), std::make_index_sequence<sizeof...(Ret)>(), pushcount, h);
}
}
}
};
} // namespace sol
#endif // SOL_FUNCTION_HPP