llvm-capstone/libcxx/include/any
Hristo Hristov 552f5549de
[libc++][any] LWG3305: any_cast<void> (#78215)
Implements: https://wg21.link/LWG3305
- https://eel.is/c++draft/any.nonmembers

---------

Co-authored-by: Zingam <zingam@outlook.com>
2024-01-20 06:08:24 +02:00

618 lines
20 KiB
C++

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP_ANY
#define _LIBCPP_ANY
/*
any synopsis
namespace std {
class bad_any_cast : public bad_cast
{
public:
virtual const char* what() const noexcept;
};
class any
{
public:
// 6.3.1 any construct/destruct
any() noexcept;
any(const any& other);
any(any&& other) noexcept;
template <class ValueType>
any(ValueType&& value);
~any();
// 6.3.2 any assignments
any& operator=(const any& rhs);
any& operator=(any&& rhs) noexcept;
template <class ValueType>
any& operator=(ValueType&& rhs);
// 6.3.3 any modifiers
template <class ValueType, class... Args>
decay_t<ValueType>& emplace(Args&&... args);
template <class ValueType, class U, class... Args>
decay_t<ValueType>& emplace(initializer_list<U>, Args&&...);
void reset() noexcept;
void swap(any& rhs) noexcept;
// 6.3.4 any observers
bool has_value() const noexcept;
const type_info& type() const noexcept;
};
// 6.4 Non-member functions
void swap(any& x, any& y) noexcept;
template <class T, class ...Args>
any make_any(Args&& ...args);
template <class T, class U, class ...Args>
any make_any(initializer_list<U>, Args&& ...args);
template<class ValueType>
ValueType any_cast(const any& operand);
template<class ValueType>
ValueType any_cast(any& operand);
template<class ValueType>
ValueType any_cast(any&& operand);
template<class ValueType>
const ValueType* any_cast(const any* operand) noexcept;
template<class ValueType>
ValueType* any_cast(any* operand) noexcept;
} // namespace std
*/
#include <__assert> // all public C++ headers provide the assertion handler
#include <__availability>
#include <__config>
#include <__memory/allocator.h>
#include <__memory/allocator_destructor.h>
#include <__memory/allocator_traits.h>
#include <__memory/unique_ptr.h>
#include <__type_traits/add_const.h>
#include <__type_traits/add_pointer.h>
#include <__type_traits/aligned_storage.h>
#include <__type_traits/conditional.h>
#include <__type_traits/decay.h>
#include <__type_traits/is_constructible.h>
#include <__type_traits/is_copy_constructible.h>
#include <__type_traits/is_function.h>
#include <__type_traits/is_nothrow_move_constructible.h>
#include <__type_traits/is_reference.h>
#include <__type_traits/is_same.h>
#include <__type_traits/is_void.h>
#include <__type_traits/remove_cv.h>
#include <__type_traits/remove_cvref.h>
#include <__type_traits/remove_reference.h>
#include <__utility/forward.h>
#include <__utility/in_place.h>
#include <__utility/move.h>
#include <__utility/unreachable.h>
#include <__verbose_abort>
#include <initializer_list>
#include <typeinfo>
#include <version>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_PUSH_MACROS
#include <__undef_macros>
namespace std {
class _LIBCPP_EXPORTED_FROM_ABI _LIBCPP_AVAILABILITY_BAD_ANY_CAST bad_any_cast : public bad_cast {
public:
const char* what() const _NOEXCEPT override;
};
} // namespace std
_LIBCPP_BEGIN_NAMESPACE_STD
#if _LIBCPP_STD_VER >= 17
_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST void __throw_bad_any_cast() {
# ifndef _LIBCPP_HAS_NO_EXCEPTIONS
throw bad_any_cast();
# else
_LIBCPP_VERBOSE_ABORT("bad_any_cast was thrown in -fno-exceptions mode");
# endif
}
// Forward declarations
class _LIBCPP_TEMPLATE_VIS any;
template <class _ValueType>
_LIBCPP_HIDE_FROM_ABI add_pointer_t<add_const_t<_ValueType>> any_cast(any const*) _NOEXCEPT;
template <class _ValueType>
_LIBCPP_HIDE_FROM_ABI add_pointer_t<_ValueType> any_cast(any*) _NOEXCEPT;
namespace __any_imp {
_LIBCPP_SUPPRESS_DEPRECATED_PUSH
using _Buffer = aligned_storage_t<3 * sizeof(void*), alignof(void*)>;
_LIBCPP_SUPPRESS_DEPRECATED_POP
template <class _Tp>
using _IsSmallObject =
integral_constant<bool,
sizeof(_Tp) <= sizeof(_Buffer) && alignof(_Buffer) % alignof(_Tp) == 0 &&
is_nothrow_move_constructible<_Tp>::value >;
enum class _Action { _Destroy, _Copy, _Move, _Get, _TypeInfo };
template <class _Tp>
struct _SmallHandler;
template <class _Tp>
struct _LargeHandler;
template <class _Tp>
struct _LIBCPP_TEMPLATE_VIS __unique_typeinfo {
static constexpr int __id = 0;
};
template <class _Tp>
constexpr int __unique_typeinfo<_Tp>::__id;
template <class _Tp>
inline _LIBCPP_HIDE_FROM_ABI constexpr const void* __get_fallback_typeid() {
return &__unique_typeinfo<remove_cv_t<remove_reference_t<_Tp>>>::__id;
}
template <class _Tp>
inline _LIBCPP_HIDE_FROM_ABI bool __compare_typeid(type_info const* __id, const void* __fallback_id) {
# if !defined(_LIBCPP_HAS_NO_RTTI)
if (__id && *__id == typeid(_Tp))
return true;
# endif
return !__id && __fallback_id == __any_imp::__get_fallback_typeid<_Tp>();
}
template <class _Tp>
using _Handler = conditional_t< _IsSmallObject<_Tp>::value, _SmallHandler<_Tp>, _LargeHandler<_Tp>>;
} // namespace __any_imp
class _LIBCPP_TEMPLATE_VIS any {
public:
// construct/destruct
_LIBCPP_HIDE_FROM_ABI constexpr any() _NOEXCEPT : __h_(nullptr) {}
_LIBCPP_HIDE_FROM_ABI any(any const& __other) : __h_(nullptr) {
if (__other.__h_)
__other.__call(_Action::_Copy, this);
}
_LIBCPP_HIDE_FROM_ABI any(any&& __other) _NOEXCEPT : __h_(nullptr) {
if (__other.__h_)
__other.__call(_Action::_Move, this);
}
template < class _ValueType,
class _Tp = decay_t<_ValueType>,
class = enable_if_t< !is_same<_Tp, any>::value && !__is_inplace_type<_ValueType>::value &&
is_copy_constructible<_Tp>::value> >
_LIBCPP_HIDE_FROM_ABI any(_ValueType&& __value);
template <class _ValueType,
class... _Args,
class _Tp = decay_t<_ValueType>,
class = enable_if_t< is_constructible<_Tp, _Args...>::value && is_copy_constructible<_Tp>::value > >
_LIBCPP_HIDE_FROM_ABI explicit any(in_place_type_t<_ValueType>, _Args&&... __args);
template <class _ValueType,
class _Up,
class... _Args,
class _Tp = decay_t<_ValueType>,
class = enable_if_t< is_constructible<_Tp, initializer_list<_Up>&, _Args...>::value &&
is_copy_constructible<_Tp>::value> >
_LIBCPP_HIDE_FROM_ABI explicit any(in_place_type_t<_ValueType>, initializer_list<_Up>, _Args&&... __args);
_LIBCPP_HIDE_FROM_ABI ~any() { this->reset(); }
// assignments
_LIBCPP_HIDE_FROM_ABI any& operator=(any const& __rhs) {
any(__rhs).swap(*this);
return *this;
}
_LIBCPP_HIDE_FROM_ABI any& operator=(any&& __rhs) _NOEXCEPT {
any(std::move(__rhs)).swap(*this);
return *this;
}
template < class _ValueType,
class _Tp = decay_t<_ValueType>,
class = enable_if_t< !is_same<_Tp, any>::value && is_copy_constructible<_Tp>::value> >
_LIBCPP_HIDE_FROM_ABI any& operator=(_ValueType&& __rhs);
template <class _ValueType,
class... _Args,
class _Tp = decay_t<_ValueType>,
class = enable_if_t< is_constructible<_Tp, _Args...>::value && is_copy_constructible<_Tp>::value> >
_LIBCPP_HIDE_FROM_ABI _Tp& emplace(_Args&&...);
template <class _ValueType,
class _Up,
class... _Args,
class _Tp = decay_t<_ValueType>,
class = enable_if_t< is_constructible<_Tp, initializer_list<_Up>&, _Args...>::value &&
is_copy_constructible<_Tp>::value> >
_LIBCPP_HIDE_FROM_ABI _Tp& emplace(initializer_list<_Up>, _Args&&...);
// 6.3.3 any modifiers
_LIBCPP_HIDE_FROM_ABI void reset() _NOEXCEPT {
if (__h_)
this->__call(_Action::_Destroy);
}
_LIBCPP_HIDE_FROM_ABI void swap(any& __rhs) _NOEXCEPT;
// 6.3.4 any observers
_LIBCPP_HIDE_FROM_ABI bool has_value() const _NOEXCEPT { return __h_ != nullptr; }
# if !defined(_LIBCPP_HAS_NO_RTTI)
_LIBCPP_HIDE_FROM_ABI const type_info& type() const _NOEXCEPT {
if (__h_) {
return *static_cast<type_info const*>(this->__call(_Action::_TypeInfo));
} else {
return typeid(void);
}
}
# endif
private:
typedef __any_imp::_Action _Action;
using _HandleFuncPtr = void* (*)(_Action, any const*, any*, const type_info*, const void* __fallback_info);
union _Storage {
_LIBCPP_HIDE_FROM_ABI constexpr _Storage() : __ptr(nullptr) {}
void* __ptr;
__any_imp::_Buffer __buf;
};
_LIBCPP_HIDE_FROM_ABI void*
__call(_Action __a, any* __other = nullptr, type_info const* __info = nullptr, const void* __fallback_info = nullptr)
const {
return __h_(__a, this, __other, __info, __fallback_info);
}
_LIBCPP_HIDE_FROM_ABI void* __call(
_Action __a, any* __other = nullptr, type_info const* __info = nullptr, const void* __fallback_info = nullptr) {
return __h_(__a, this, __other, __info, __fallback_info);
}
template <class>
friend struct __any_imp::_SmallHandler;
template <class>
friend struct __any_imp::_LargeHandler;
template <class _ValueType>
friend add_pointer_t<add_const_t<_ValueType>> any_cast(any const*) _NOEXCEPT;
template <class _ValueType>
friend add_pointer_t<_ValueType> any_cast(any*) _NOEXCEPT;
_HandleFuncPtr __h_ = nullptr;
_Storage __s_;
};
namespace __any_imp {
template <class _Tp>
struct _LIBCPP_TEMPLATE_VIS _SmallHandler {
_LIBCPP_HIDE_FROM_ABI static void*
__handle(_Action __act, any const* __this, any* __other, type_info const* __info, const void* __fallback_info) {
switch (__act) {
case _Action::_Destroy:
__destroy(const_cast<any&>(*__this));
return nullptr;
case _Action::_Copy:
__copy(*__this, *__other);
return nullptr;
case _Action::_Move:
__move(const_cast<any&>(*__this), *__other);
return nullptr;
case _Action::_Get:
return __get(const_cast<any&>(*__this), __info, __fallback_info);
case _Action::_TypeInfo:
return __type_info();
}
__libcpp_unreachable();
}
template <class... _Args>
_LIBCPP_HIDE_FROM_ABI static _Tp& __create(any& __dest, _Args&&... __args) {
typedef allocator<_Tp> _Alloc;
typedef allocator_traits<_Alloc> _ATraits;
_Alloc __a;
_Tp* __ret = static_cast<_Tp*>(static_cast<void*>(&__dest.__s_.__buf));
_ATraits::construct(__a, __ret, std::forward<_Args>(__args)...);
__dest.__h_ = &_SmallHandler::__handle;
return *__ret;
}
private:
_LIBCPP_HIDE_FROM_ABI static void __destroy(any& __this) {
typedef allocator<_Tp> _Alloc;
typedef allocator_traits<_Alloc> _ATraits;
_Alloc __a;
_Tp* __p = static_cast<_Tp*>(static_cast<void*>(&__this.__s_.__buf));
_ATraits::destroy(__a, __p);
__this.__h_ = nullptr;
}
_LIBCPP_HIDE_FROM_ABI static void __copy(any const& __this, any& __dest) {
_SmallHandler::__create(__dest, *static_cast<_Tp const*>(static_cast<void const*>(&__this.__s_.__buf)));
}
_LIBCPP_HIDE_FROM_ABI static void __move(any& __this, any& __dest) {
_SmallHandler::__create(__dest, std::move(*static_cast<_Tp*>(static_cast<void*>(&__this.__s_.__buf))));
__destroy(__this);
}
_LIBCPP_HIDE_FROM_ABI static void* __get(any& __this, type_info const* __info, const void* __fallback_id) {
if (__any_imp::__compare_typeid<_Tp>(__info, __fallback_id))
return static_cast<void*>(&__this.__s_.__buf);
return nullptr;
}
_LIBCPP_HIDE_FROM_ABI static void* __type_info() {
# if !defined(_LIBCPP_HAS_NO_RTTI)
return const_cast<void*>(static_cast<void const*>(&typeid(_Tp)));
# else
return nullptr;
# endif
}
};
template <class _Tp>
struct _LIBCPP_TEMPLATE_VIS _LargeHandler {
_LIBCPP_HIDE_FROM_ABI static void*
__handle(_Action __act, any const* __this, any* __other, type_info const* __info, void const* __fallback_info) {
switch (__act) {
case _Action::_Destroy:
__destroy(const_cast<any&>(*__this));
return nullptr;
case _Action::_Copy:
__copy(*__this, *__other);
return nullptr;
case _Action::_Move:
__move(const_cast<any&>(*__this), *__other);
return nullptr;
case _Action::_Get:
return __get(const_cast<any&>(*__this), __info, __fallback_info);
case _Action::_TypeInfo:
return __type_info();
}
__libcpp_unreachable();
}
template <class... _Args>
_LIBCPP_HIDE_FROM_ABI static _Tp& __create(any& __dest, _Args&&... __args) {
typedef allocator<_Tp> _Alloc;
typedef allocator_traits<_Alloc> _ATraits;
typedef __allocator_destructor<_Alloc> _Dp;
_Alloc __a;
unique_ptr<_Tp, _Dp> __hold(_ATraits::allocate(__a, 1), _Dp(__a, 1));
_Tp* __ret = __hold.get();
_ATraits::construct(__a, __ret, std::forward<_Args>(__args)...);
__dest.__s_.__ptr = __hold.release();
__dest.__h_ = &_LargeHandler::__handle;
return *__ret;
}
private:
_LIBCPP_HIDE_FROM_ABI static void __destroy(any& __this) {
typedef allocator<_Tp> _Alloc;
typedef allocator_traits<_Alloc> _ATraits;
_Alloc __a;
_Tp* __p = static_cast<_Tp*>(__this.__s_.__ptr);
_ATraits::destroy(__a, __p);
_ATraits::deallocate(__a, __p, 1);
__this.__h_ = nullptr;
}
_LIBCPP_HIDE_FROM_ABI static void __copy(any const& __this, any& __dest) {
_LargeHandler::__create(__dest, *static_cast<_Tp const*>(__this.__s_.__ptr));
}
_LIBCPP_HIDE_FROM_ABI static void __move(any& __this, any& __dest) {
__dest.__s_.__ptr = __this.__s_.__ptr;
__dest.__h_ = &_LargeHandler::__handle;
__this.__h_ = nullptr;
}
_LIBCPP_HIDE_FROM_ABI static void* __get(any& __this, type_info const* __info, void const* __fallback_info) {
if (__any_imp::__compare_typeid<_Tp>(__info, __fallback_info))
return static_cast<void*>(__this.__s_.__ptr);
return nullptr;
}
_LIBCPP_HIDE_FROM_ABI static void* __type_info() {
# if !defined(_LIBCPP_HAS_NO_RTTI)
return const_cast<void*>(static_cast<void const*>(&typeid(_Tp)));
# else
return nullptr;
# endif
}
};
} // namespace __any_imp
template <class _ValueType, class _Tp, class>
any::any(_ValueType&& __v) : __h_(nullptr) {
__any_imp::_Handler<_Tp>::__create(*this, std::forward<_ValueType>(__v));
}
template <class _ValueType, class... _Args, class _Tp, class>
any::any(in_place_type_t<_ValueType>, _Args&&... __args) {
__any_imp::_Handler<_Tp>::__create(*this, std::forward<_Args>(__args)...);
}
template <class _ValueType, class _Up, class... _Args, class _Tp, class>
any::any(in_place_type_t<_ValueType>, initializer_list<_Up> __il, _Args&&... __args) {
__any_imp::_Handler<_Tp>::__create(*this, __il, std::forward<_Args>(__args)...);
}
template <class _ValueType, class, class>
inline _LIBCPP_HIDE_FROM_ABI any& any::operator=(_ValueType&& __v) {
any(std::forward<_ValueType>(__v)).swap(*this);
return *this;
}
template <class _ValueType, class... _Args, class _Tp, class>
inline _LIBCPP_HIDE_FROM_ABI _Tp& any::emplace(_Args&&... __args) {
reset();
return __any_imp::_Handler<_Tp>::__create(*this, std::forward<_Args>(__args)...);
}
template <class _ValueType, class _Up, class... _Args, class _Tp, class>
inline _LIBCPP_HIDE_FROM_ABI _Tp& any::emplace(initializer_list<_Up> __il, _Args&&... __args) {
reset();
return __any_imp::_Handler<_Tp>::__create(*this, __il, std::forward<_Args>(__args)...);
}
inline _LIBCPP_HIDE_FROM_ABI void any::swap(any& __rhs) _NOEXCEPT {
if (this == &__rhs)
return;
if (__h_ && __rhs.__h_) {
any __tmp;
__rhs.__call(_Action::_Move, &__tmp);
this->__call(_Action::_Move, &__rhs);
__tmp.__call(_Action::_Move, this);
} else if (__h_) {
this->__call(_Action::_Move, &__rhs);
} else if (__rhs.__h_) {
__rhs.__call(_Action::_Move, this);
}
}
// 6.4 Non-member functions
inline _LIBCPP_HIDE_FROM_ABI void swap(any& __lhs, any& __rhs) _NOEXCEPT { __lhs.swap(__rhs); }
template <class _Tp, class... _Args>
inline _LIBCPP_HIDE_FROM_ABI any make_any(_Args&&... __args) {
return any(in_place_type<_Tp>, std::forward<_Args>(__args)...);
}
template <class _Tp, class _Up, class... _Args>
inline _LIBCPP_HIDE_FROM_ABI any make_any(initializer_list<_Up> __il, _Args&&... __args) {
return any(in_place_type<_Tp>, __il, std::forward<_Args>(__args)...);
}
template <class _ValueType>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST _ValueType any_cast(any const& __v) {
using _RawValueType = __remove_cvref_t<_ValueType>;
static_assert(is_constructible<_ValueType, _RawValueType const&>::value,
"ValueType is required to be a const lvalue reference "
"or a CopyConstructible type");
auto __tmp = std::any_cast<add_const_t<_RawValueType>>(&__v);
if (__tmp == nullptr)
__throw_bad_any_cast();
return static_cast<_ValueType>(*__tmp);
}
template <class _ValueType>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST _ValueType any_cast(any& __v) {
using _RawValueType = __remove_cvref_t<_ValueType>;
static_assert(is_constructible<_ValueType, _RawValueType&>::value,
"ValueType is required to be an lvalue reference "
"or a CopyConstructible type");
auto __tmp = std::any_cast<_RawValueType>(&__v);
if (__tmp == nullptr)
__throw_bad_any_cast();
return static_cast<_ValueType>(*__tmp);
}
template <class _ValueType>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST _ValueType any_cast(any&& __v) {
using _RawValueType = __remove_cvref_t<_ValueType>;
static_assert(is_constructible<_ValueType, _RawValueType>::value,
"ValueType is required to be an rvalue reference "
"or a CopyConstructible type");
auto __tmp = std::any_cast<_RawValueType>(&__v);
if (__tmp == nullptr)
__throw_bad_any_cast();
return static_cast<_ValueType>(std::move(*__tmp));
}
template <class _ValueType>
inline _LIBCPP_HIDE_FROM_ABI add_pointer_t<add_const_t<_ValueType>> any_cast(any const* __any) _NOEXCEPT {
static_assert(!is_void_v<_ValueType>, "_ValueType may not be void.");
static_assert(!is_reference<_ValueType>::value, "_ValueType may not be a reference.");
return std::any_cast<_ValueType>(const_cast<any*>(__any));
}
template <class _RetType>
inline _LIBCPP_HIDE_FROM_ABI _RetType __pointer_or_func_cast(void* __p, /*IsFunction*/ false_type) noexcept {
return static_cast<_RetType>(__p);
}
template <class _RetType>
inline _LIBCPP_HIDE_FROM_ABI _RetType __pointer_or_func_cast(void*, /*IsFunction*/ true_type) noexcept {
return nullptr;
}
template <class _ValueType>
_LIBCPP_HIDE_FROM_ABI add_pointer_t<_ValueType> any_cast(any* __any) _NOEXCEPT {
using __any_imp::_Action;
static_assert(!is_void_v<_ValueType>, "_ValueType may not be void.");
static_assert(!is_reference<_ValueType>::value, "_ValueType may not be a reference.");
typedef add_pointer_t<_ValueType> _ReturnType;
if (__any && __any->__h_) {
void* __p = __any->__call(
_Action::_Get,
nullptr,
# if !defined(_LIBCPP_HAS_NO_RTTI)
&typeid(_ValueType),
# else
nullptr,
# endif
__any_imp::__get_fallback_typeid<_ValueType>());
return std::__pointer_or_func_cast<_ReturnType>(__p, is_function<_ValueType>{});
}
return nullptr;
}
#endif // _LIBCPP_STD_VER >= 17
_LIBCPP_END_NAMESPACE_STD
_LIBCPP_POP_MACROS
#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 17
# include <chrono>
#endif
#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
# include <atomic>
# include <concepts>
# include <cstdlib>
# include <iosfwd>
# include <iterator>
# include <memory>
# include <stdexcept>
# include <type_traits>
# include <variant>
#endif
#endif // _LIBCPP_ANY