sol2/include/sol/stack_reference.hpp
2020-08-13 10:42:37 -04:00

235 lines
7.3 KiB
C++

// sol3
// The MIT License (MIT)
// Copyright (c) 2013-2020 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_STACK_REFERENCE_HPP
#define SOL_STACK_REFERENCE_HPP
#include <sol/types.hpp>
namespace sol {
namespace detail {
inline bool xmovable(lua_State* leftL, lua_State* rightL) {
if (rightL == nullptr || leftL == nullptr || leftL == rightL) {
return false;
}
const void* leftregistry = lua_topointer(leftL, LUA_REGISTRYINDEX);
const void* rightregistry = lua_topointer(rightL, LUA_REGISTRYINDEX);
return leftregistry == rightregistry;
}
} // namespace detail
class stateless_stack_reference {
private:
friend class stack_reference;
int index = 0;
int registry_index() const noexcept {
return LUA_NOREF;
}
public:
stateless_stack_reference() noexcept = default;
stateless_stack_reference(lua_nil_t) noexcept : stateless_stack_reference(){};
stateless_stack_reference(lua_State* L, int i) noexcept : stateless_stack_reference(absolute_index(L, i)) {
}
stateless_stack_reference(lua_State*, absolute_index i) noexcept : stateless_stack_reference(i) {
}
stateless_stack_reference(lua_State*, raw_index i) noexcept : stateless_stack_reference(i) {
}
stateless_stack_reference(absolute_index i) noexcept : index(i) {
}
stateless_stack_reference(raw_index i) noexcept : index(i) {
}
stateless_stack_reference(lua_State*, ref_index) noexcept = delete;
stateless_stack_reference(ref_index) noexcept = delete;
stateless_stack_reference(const reference&) noexcept = delete;
stateless_stack_reference(const stateless_stack_reference&) noexcept = default;
stateless_stack_reference(stateless_stack_reference&& o) noexcept = default;
stateless_stack_reference& operator=(stateless_stack_reference&&) noexcept = default;
stateless_stack_reference& operator=(const stateless_stack_reference&) noexcept = default;
int push(lua_State* L) const noexcept {
#if SOL_IS_ON(SOL_SAFE_STACK_CHECK_I_)
luaL_checkstack(L, 1, "not enough Lua stack space to push a single reference value");
#endif // make sure stack doesn't overflow
lua_pushvalue(L, index);
return 1;
}
void pop(lua_State* L, int n = 1) const noexcept {
lua_pop(L, n);
}
int stack_index() const noexcept {
return index;
}
const void* pointer(lua_State* L) const noexcept {
const void* vp = lua_topointer(L, stack_index());
return vp;
}
type get_type(lua_State* L) const noexcept {
int result = lua_type(L, index);
return static_cast<type>(result);
}
bool valid(lua_State* L) const noexcept {
type t = get_type(L);
return t != type::lua_nil && t != type::none;
}
void abandon(lua_State* = nullptr) {
index = 0;
}
};
class stack_reference : public stateless_stack_reference {
private:
lua_State* luastate = nullptr;
public:
stack_reference() noexcept = default;
stack_reference(lua_nil_t) noexcept
: stack_reference() {};
stack_reference(lua_State* L, lua_nil_t) noexcept : stateless_stack_reference(L, 0), luastate(L) {
}
stack_reference(lua_State* L, int i) noexcept : stateless_stack_reference(L, i), luastate(L) {
}
stack_reference(lua_State* L, absolute_index i) noexcept : stateless_stack_reference(L, i), luastate(L) {
}
stack_reference(lua_State* L, raw_index i) noexcept : stateless_stack_reference(L, i), luastate(L) {
}
stack_reference(lua_State* L, ref_index i) noexcept = delete;
stack_reference(lua_State* L, const reference& r) noexcept = delete;
stack_reference(lua_State* L, const stack_reference& r) noexcept
: luastate(L) {
if (!r.valid()) {
index = 0;
return;
}
int i = r.stack_index();
if (detail::xmovable(lua_state(), r.lua_state())) {
#if SOL_IS_ON(SOL_SAFE_STACK_CHECK_I_)
luaL_checkstack(L, 1, "not enough Lua stack space to push a single reference value");
#endif // make sure stack doesn't overflow
lua_pushvalue(r.lua_state(), r.index);
lua_xmove(r.lua_state(), luastate, 1);
i = absolute_index(luastate, -1);
}
index = i;
}
stack_reference(stack_reference&& o) noexcept = default;
stack_reference& operator=(stack_reference&&) noexcept = default;
stack_reference(const stack_reference&) noexcept = default;
stack_reference& operator=(const stack_reference&) noexcept = default;
int push() const noexcept {
return push(lua_state());
}
int push(lua_State* Ls) const noexcept {
return stateless_stack_reference::push(Ls);
}
void pop() const noexcept {
pop(lua_state());
}
void pop(lua_State* Ls, int n = 1) const noexcept {
stateless_stack_reference::pop(Ls, n);
}
const void* pointer() const noexcept {
return stateless_stack_reference::pointer(lua_state());
}
type get_type() const noexcept {
return stateless_stack_reference::get_type(lua_state());
}
lua_State* lua_state() const noexcept {
return luastate;
}
bool valid() const noexcept {
return stateless_stack_reference::valid(lua_state());
}
void abandon () {
stateless_stack_reference::abandon(lua_state());
}
};
inline bool operator==(const stack_reference& l, const stack_reference& r) {
return lua_compare(l.lua_state(), l.stack_index(), r.stack_index(), LUA_OPEQ) == 0;
}
inline bool operator!=(const stack_reference& l, const stack_reference& r) {
return !operator==(l, r);
}
inline bool operator==(const stack_reference& lhs, const lua_nil_t&) {
return !lhs.valid();
}
inline bool operator==(const lua_nil_t&, const stack_reference& rhs) {
return !rhs.valid();
}
inline bool operator!=(const stack_reference& lhs, const lua_nil_t&) {
return lhs.valid();
}
inline bool operator!=(const lua_nil_t&, const stack_reference& rhs) {
return rhs.valid();
}
struct stack_reference_equals {
bool operator()(const lua_nil_t& lhs, const stack_reference& rhs) const {
return lhs == rhs;
}
bool operator()(const stack_reference& lhs, const lua_nil_t& rhs) const {
return lhs == rhs;
}
bool operator()(const stack_reference& lhs, const stack_reference& rhs) const {
return lhs == rhs;
}
};
struct stack_reference_hash {
typedef stack_reference argument_type;
typedef std::size_t result_type;
result_type operator()(const argument_type& lhs) const {
std::hash<const void*> h;
return h(lhs.pointer());
}
};
} // namespace sol
#endif // SOL_STACK_REFERENCE_HPP