--- /dev/null
+// <experimental/any> -*- C++ -*-
+
+// Copyright (C) 2014 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+// <http://www.gnu.org/licenses/>.
+
+/** @file experimental/any
+ * This is a TS C++ Library header.
+ */
+
+#ifndef _GLIBCXX_EXPERIMENTAL_ANY
+#define _GLIBCXX_EXPERIMENTAL_ANY 1
+
+#pragma GCC system_header
+
+#if __cplusplus <= 201103L
+# include <bits/c++14_warning.h>
+#else
+
+#include <typeinfo>
+#include <memory>
+#include <utility>
+#include <type_traits>
+#include <bits/alloc_traits.h>
+#include <bits/uses_allocator.h>
+#include <bits/functexcept.h>
+
+namespace std _GLIBCXX_VISIBILITY(default)
+{
+namespace experimental
+{
+inline namespace any_v1
+{
+_GLIBCXX_BEGIN_NAMESPACE_VERSION
+
+ /**
+ * @defgroup any Type-safe container of any type
+ * @ingroup experimental
+ *
+ * A type-safe container for single values of value types, as
+ * described in n3804 "Any Library Proposal (Revision 3)".
+ *
+ * @{
+ */
+
+ /**
+ * @brief Exception class thrown by a failed @c any_cast
+ * @ingroup exceptions
+ */
+ class bad_any_cast : public bad_cast
+ {
+ public:
+ virtual const char* what() const noexcept { return "bad_any_cast"; }
+ };
+
+ [[gnu::noreturn]] inline void __throw_bad_any_cast()
+ {
+#ifdef __EXCEPTIONS
+ throw bad_any_cast{};
+#else
+ __builtin_abort();
+#endif
+ }
+
+ /**
+ * @brief A type-safe container of any type.
+ *
+ * An @c any object's state is either empty or it stores a contained object
+ * of CopyConstructible type.
+ */
+ class any
+ {
+ // Holds either pointer to a heap object or the contained object itself.
+ union _Storage
+ {
+ void* _M_ptr;
+ std::aligned_storage<sizeof(_M_ptr), sizeof(_M_ptr)>::type _M_buffer;
+ };
+
+ template<typename _Tp, typename _Safe = is_nothrow_copy_constructible<_Tp>,
+ bool _Fits = (sizeof(_Tp) <= sizeof(_Storage))>
+ using _Internal = std::integral_constant<bool, _Safe::value && _Fits>;
+
+ template<typename _Tp>
+ struct _Manager_internal; // uses small-object optimization
+
+ template<typename _Tp>
+ struct _Manager_external; // creates contained object on the heap
+
+ template<typename _Tp>
+ using _Manager = conditional_t<_Internal<_Tp>::value,
+ _Manager_internal<_Tp>,
+ _Manager_external<_Tp>>;
+
+#ifdef __GXX_RTTI
+ // When RTTI is disabled __any_caster assumes the manager is either
+ // _Manager_internal or _Manager_external, so this type must not be used.
+ template<typename _Tp, typename _Alloc>
+ struct _Manager_alloc; // creates contained object using an allocator
+
+ template<typename _Tp, typename _Alloc, typename _TpAlloc
+ = typename allocator_traits<_Alloc>::template rebind_alloc<_Tp>>
+ using _ManagerAlloc = conditional_t<_Internal<_Tp>::value,
+ _Manager_internal<_Tp>,
+ _Manager_alloc<_Tp, _TpAlloc>>;
+#endif
+
+ template<typename _Tp, typename _Decayed = decay_t<_Tp>>
+ using _Decay = enable_if_t<!is_same<_Decayed, any>::value, _Decayed>;
+
+ public:
+ // construct/destruct
+
+ /// Default constructor, creates an empty object.
+ any() noexcept : _M_manager(nullptr) { }
+
+ /// Copy constructor, copies the state of @p __other
+ any(const any& __other) : _M_manager(__other._M_manager)
+ {
+ if (!__other.empty())
+ {
+ _Arg __arg;
+ __arg._M_any = this;
+ _M_manager(_Op_clone, &__other, &__arg);
+ }
+ }
+
+ /**
+ * @brief Move constructor, transfer the state from @p __other
+ *
+ * @post @c __other.empty() (not guaranteed for other implementations)
+ */
+ any(any&& __other) noexcept
+ : _M_manager(__other._M_manager),
+ _M_storage(__other._M_storage)
+ { __other._M_manager = nullptr; }
+
+ /// Construct with a copy of @p __value as the contained object.
+ template <typename _ValueType, typename _Tp = _Decay<_ValueType>,
+ typename _Mgr = _Manager<_Tp>>
+ any(_ValueType&& __value)
+ : _M_manager(&_Mgr::_S_manage),
+ _M_storage(_Mgr::_S_create(std::forward<_ValueType>(__value)))
+ {
+ static_assert(is_copy_constructible<_Tp>::value,
+ "The contained object must be CopyConstructible");
+ }
+
+ /// Allocator-extended default constructor (the allocator is ignored).
+ template <typename _Allocator>
+ any(allocator_arg_t, const _Allocator&) noexcept : any() { }
+
+#ifdef __GXX_RTTI
+ /// Construct with a copy of @p __value as the contained object.
+ template <typename _Allocator, typename _ValueType,
+ typename _Tp = _Decay<_ValueType>,
+ typename _Mgr = _ManagerAlloc<_Tp, _Allocator>>
+ any(allocator_arg_t, const _Allocator& __a, _ValueType&& __value)
+ : _M_manager(&_Mgr::_S_manage),
+ _M_storage(_Mgr::_S_alloc(__a, std::forward<_ValueType>(__value)))
+ {
+ static_assert(is_copy_constructible<_Tp>::value,
+ "The contained object must be CopyConstructible");
+ }
+#endif
+
+ /* TODO: implement this somehow
+ /// Allocator-extended copy constructor.
+ template <class _Allocator>
+ any(allocator_arg_t, const _Allocator& __a, const any& __other);
+ */
+
+ /// Allocator-extended move constructor (the allocator is ignored).
+ template <typename _Allocator>
+ any(allocator_arg_t, const _Allocator&, any&& __other) noexcept
+ : any(std::move(__other)) { }
+
+ /// Destructor, calls @c clear()
+ ~any() { clear(); }
+
+ // assignments
+
+ /// Copy the state of
+ any& operator=(const any& __rhs)
+ {
+ any(__rhs).swap(*this);
+ return *this;
+ }
+
+ /**
+ * @brief Move assignment operator
+ *
+ * @post @c __rhs.empty() (not guaranteed for other implementations)
+ */
+ any& operator=(any&& __rhs) noexcept
+ {
+ any(std::move(__rhs)).swap(*this);
+ return *this;
+ }
+
+ /// Store a copy of @p __rhs as the contained object.
+ template<typename _ValueType>
+ any& operator=(_ValueType&& __rhs)
+ {
+ any(std::forward<_ValueType>(__rhs)).swap(*this);
+ return *this;
+ }
+
+ // modifiers
+
+ /// If not empty, destroy the contained object.
+ void clear() noexcept
+ {
+ if (!empty())
+ {
+ _M_manager(_Op_destroy, this, nullptr);
+ _M_manager = nullptr;
+ }
+ }
+
+ /// Exchange state with another object.
+ void swap(any& __rhs) noexcept
+ {
+ std::swap(_M_manager, __rhs._M_manager);
+ std::swap(_M_storage, __rhs._M_storage);
+ }
+
+ // observers
+
+ /// Reports whether there is a contained object or not.
+ bool empty() const noexcept { return _M_manager == nullptr; }
+
+#ifdef __GXX_RTTI
+ /// The @c typeid of the contained object, or @c typeid(void) if empty.
+ const type_info& type() const noexcept
+ {
+ if (empty())
+ return typeid(void);
+ _Arg __arg;
+ _M_manager(_Op_get_type_info, this, &__arg);
+ return *__arg._M_typeinfo;
+ }
+#endif
+
+ template<typename _Tp>
+ static constexpr bool __is_valid_cast()
+ { return __or_<is_reference<_Tp>, is_copy_constructible<_Tp>>::value; }
+
+ private:
+ enum _Op { _Op_access, _Op_get_type_info, _Op_clone, _Op_destroy };
+
+ union _Arg
+ {
+ void* _M_obj;
+ const std::type_info* _M_typeinfo;
+ any* _M_any;
+ };
+
+ void (*_M_manager)(_Op, const any*, _Arg*);
+ _Storage _M_storage;
+
+ template<typename _Tp>
+ friend void* __any_caster(const any* __any)
+ {
+#ifdef __GXX_RTTI
+ if (__any->type() != typeid(_Tp))
+ return nullptr;
+#else
+ if (__any->_M_manager != &_Manager<decay_t<_Tp>>::_S_manage)
+ return nullptr;
+#endif
+ _Arg __arg;
+ __any->_M_manager(_Op_access, __any, &__arg);
+ return __arg._M_obj;
+ }
+
+ // Manage in-place contained object.
+ template<typename _Tp>
+ struct _Manager_internal
+ {
+ static void
+ _S_manage(_Op __which, const any* __anyp, _Arg* __arg);
+
+ template<typename _Up>
+ static _Storage
+ _S_create(_Up&& __value)
+ {
+ _Storage __storage;
+ void* __addr = &__storage._M_buffer;
+ ::new (__addr) _Tp(std::forward<_Up>(__value));
+ return __storage;
+ }
+
+ template<typename _Alloc, typename _Up>
+ static _Storage
+ _S_alloc(const _Alloc&, _Up&& __value)
+ {
+ return _S_create(std::forward<_Up>(__value));
+ }
+ };
+
+ // Manage external contained object.
+ template<typename _Tp>
+ struct _Manager_external
+ {
+ static void
+ _S_manage(_Op __which, const any* __anyp, _Arg* __arg);
+
+ template<typename _Up>
+ static _Storage
+ _S_create(_Up&& __value)
+ {
+ _Storage __storage;
+ __storage._M_ptr = new _Tp(std::forward<_Up>(__value));
+ return __storage;
+ }
+ };
+
+#ifdef __GXX_RTTI
+ // Manage external contained object using an allocator
+ template<typename _Tp, typename _Alloc>
+ struct _Manager_alloc
+ {
+ static_assert(std::is_same<_Tp, typename _Alloc::value_type>::value,
+ "Allocator's value_type is correct");
+
+ // Type that holds contained object and allocator
+ struct _Data;
+
+ using _Traits = typename std::allocator_traits<_Alloc>::template
+ rebind_traits<_Data>;
+
+ static void
+ _S_manage(_Op __which, const any* __anyp, _Arg* __arg);
+
+ template<typename _Up>
+ static _Storage
+ _S_alloc(const _Alloc& __a, _Up&& __value);
+ };
+#endif
+ };
+
+ /// Exchange the states of two @c any objects.
+ inline void swap(any& __x, any& __y) noexcept { __x.swap(__y); }
+
+ /**
+ * @brief Access the contained object.
+ *
+ * @tparam _ValueType A const-reference or CopyConstructible type.
+ * @param __any The object to access.
+ * @return The contained object.
+ * @throw bad_any_cast If <code>
+ * __any.type() != typeid(remove_reference_t<_ValueType>)
+ * </code>
+ */
+ template<typename _ValueType>
+ inline _ValueType any_cast(const any& __any)
+ {
+ static_assert(any::__is_valid_cast<_ValueType>(),
+ "Template argument must be a reference or CopyConstructible type");
+ auto __p = any_cast<add_const_t<remove_reference_t<_ValueType>>>(&__any);
+ if (__p)
+ return *__p;
+ __throw_bad_any_cast();
+ }
+
+ /**
+ * @brief Access the contained object.
+ *
+ * @tparam _ValueType A reference or CopyConstructible type.
+ * @param __any The object to access.
+ * @return The contained object.
+ * @throw bad_any_cast If <code>
+ * __any.type() != typeid(remove_reference_t<_ValueType>)
+ * </code>
+ */
+ template<typename _ValueType>
+ inline _ValueType any_cast(any& __any)
+ {
+ static_assert(any::__is_valid_cast<_ValueType>(),
+ "Template argument must be a reference or CopyConstructible type");
+ auto __p = any_cast<remove_reference_t<_ValueType>>(&__any);
+ if (__p)
+ return *__p;
+ __throw_bad_any_cast();
+ }
+
+ /**
+ * @brief Access the contained object.
+ *
+ * @tparam _ValueType A reference or CopyConstructible type.
+ * @param __any The object to access.
+ * @return The contained object.
+ * @throw bad_any_cast If <code>
+ * __any.type() != typeid(remove_reference_t<_ValueType>)
+ * </code>
+ */
+ template<typename _ValueType>
+ inline _ValueType any_cast(any&& __any)
+ {
+ static_assert(any::__is_valid_cast<_ValueType>(),
+ "Template argument must be a reference or CopyConstructible type");
+ auto __p = any_cast<remove_reference_t<_ValueType>>(&__any);
+ if (__p)
+ return *__p;
+ __throw_bad_any_cast();
+ }
+
+ /**
+ * @brief Access the contained object.
+ *
+ * @tparam _ValueType The type of the contained object.
+ * @param __any A pointer to the object to access.
+ * @return The address of the contained object if <code>
+ * __any != nullptr && __any.type() == typeid(_ValueType)
+ * </code>, otherwise a null pointer.
+ */
+ template<typename _ValueType>
+ inline const _ValueType* any_cast(const any* __any) noexcept
+ {
+ if (__any)
+ return static_cast<_ValueType*>(__any_caster<_ValueType>(__any));
+ return nullptr;
+ }
+
+ /**
+ * @brief Access the contained object.
+ *
+ * @tparam _ValueType The type of the contained object.
+ * @param __any A pointer to the object to access.
+ * @return The address of the contained object if <code>
+ * __any != nullptr && __any.type() == typeid(_ValueType)
+ * </code>, otherwise a null pointer.
+ */
+ template<typename _ValueType>
+ inline _ValueType* any_cast(any* __any) noexcept
+ {
+ if (__any)
+ return static_cast<_ValueType*>(__any_caster<_ValueType>(__any));
+ return nullptr;
+ }
+
+#ifdef __GXX_RTTI
+ template<typename _Tp, typename _Alloc>
+ struct any::_Manager_alloc<_Tp, _Alloc>::_Data
+ {
+ using _Traits = std::allocator_traits<_Alloc>;
+
+ std::tuple<_Alloc, __gnu_cxx::__aligned_buffer<_Tp>> _M_data;
+
+ _Alloc& _M_alloc() { return std::get<0>(_M_data); }
+ const _Alloc& _M_alloc() const { return std::get<0>(_M_data); }
+
+ _Tp* _M_obj() { return std::get<1>(_M_data)._M_ptr(); }
+ const _Tp* _M_obj() const { return std::get<1>(_M_data)._M_ptr(); }
+
+ template<typename _Up>
+ _Data(const _Alloc& __a, _Up&& __val) : _M_data(__a, nullptr)
+ {
+ this->_M_construct(std::__use_alloc<_Tp>(_M_alloc()),
+ std::forward<_Up>(__val));
+ }
+
+ ~_Data() { _Traits::destroy(_M_alloc(), _M_obj()); }
+
+ template<typename _Up>
+ void
+ _M_construct(__uses_alloc0, _Up&& __val)
+ {
+ _Traits::construct(_M_alloc(), _M_obj(),
+ std::forward<_Up>(__val));
+ }
+
+ template<typename _Up>
+ void
+ _M_construct(__uses_alloc1<_Alloc> __a, _Up&& __val)
+ {
+ _Traits::construct(__a._M_a, _M_obj(),
+ std::allocator_arg, __a._M_a,
+ std::forward<_Up>(__val));
+ }
+
+ template<typename _Up>
+ void
+ _M_construct(__uses_alloc2<_Alloc> __a, _Up&& __val)
+ {
+ _Traits::construct(__a._M_a, _M_obj(),
+ std::forward<_Up>(__val), __a._M_a);
+ }
+ };
+
+ template<typename _Tp, typename _Alloc>
+ template<typename _Up>
+ any::_Storage
+ any::_Manager_alloc<_Tp, _Alloc>::
+ _S_alloc(const _Alloc& __a, _Up&& __value)
+ {
+ typename _Traits::allocator_type __a2(__a);
+ auto __ptr = _Traits::allocate(__a2, 1);
+ __try
+ {
+ any::_Storage __storage;
+ __storage._M_ptr = std::__addressof(*__ptr);
+ ::new(__storage._M_ptr) _Data{__a, std::forward<_Up>(__value)};
+ return __storage;
+ }
+ __catch(...)
+ {
+ _Traits::deallocate(__a2, __ptr, 1);
+ __throw_exception_again;
+ }
+ }
+#endif
+
+ template<typename _Tp>
+ void
+ any::_Manager_internal<_Tp>::
+ _S_manage(_Op __which, const any* __any, _Arg* __arg)
+ {
+ // The contained object is in _M_storage._M_buffer
+ auto __ptr = reinterpret_cast<const _Tp*>(&__any->_M_storage._M_buffer);
+ switch (__which)
+ {
+ case _Op_access:
+ __arg->_M_obj = const_cast<_Tp*>(__ptr);
+ break;
+ case _Op_get_type_info:
+#ifdef __GXX_RTTI
+ __arg->_M_typeinfo = &typeid(_Tp);
+#endif
+ break;
+ case _Op_clone:
+ ::new(&__arg->_M_any->_M_storage._M_buffer) _Tp(*__ptr);
+ break;
+ case _Op_destroy:
+ __ptr->~_Tp();
+ break;
+ }
+ }
+
+ template<typename _Tp>
+ void
+ any::_Manager_external<_Tp>::
+ _S_manage(_Op __which, const any* __any, _Arg* __arg)
+ {
+ // The contained object is *_M_storage._M_ptr
+ auto __ptr = static_cast<const _Tp*>(__any->_M_storage._M_ptr);
+ switch (__which)
+ {
+ case _Op_access:
+ __arg->_M_obj = const_cast<_Tp*>(__ptr);
+ break;
+ case _Op_get_type_info:
+#ifdef __GXX_RTTI
+ __arg->_M_typeinfo = &typeid(_Tp);
+#endif
+ break;
+ case _Op_clone:
+ __arg->_M_any->_M_storage._M_ptr = new _Tp(*__ptr);
+ break;
+ case _Op_destroy:
+ delete __ptr;
+ break;
+ }
+ }
+
+#ifdef __GXX_RTTI
+ template<typename _Tp, typename _Alloc>
+ void
+ any::_Manager_alloc<_Tp, _Alloc>::
+ _S_manage(_Op __which, const any* __any, _Arg* __arg)
+ {
+ // The contained object is at _M_storage._M_ptr->_M_obj()
+ auto __ptr = static_cast<const _Data*>(__any->_M_storage._M_ptr);
+ switch (__which)
+ {
+ case _Op_access:
+ __arg->_M_obj = const_cast<_Tp*>(__ptr->_M_obj());
+ break;
+ case _Op_get_type_info:
+ __arg->_M_typeinfo = &typeid(_Tp);
+ break;
+ case _Op_clone:
+ __arg->_M_any->_M_storage
+ = _S_alloc(__ptr->_M_alloc(), *__ptr->_M_obj());
+ break;
+ case _Op_destroy:
+ {
+ using _PtrTr = pointer_traits<typename _Traits::pointer>;
+ typename _Traits::allocator_type __a(__ptr->_M_alloc());
+ auto __alloc_ptr = _PtrTr::pointer_to(*const_cast<_Data*>(__ptr));
+ __ptr->~_Data();
+ _Traits::deallocate(__a, __alloc_ptr, 1);
+ }
+ break;
+ }
+ }
+#endif
+
+ // @} group any
+_GLIBCXX_END_NAMESPACE_VERSION
+} // namespace any_v1
+} // namespace experimental
+} // namespace std
+
+#endif // C++14
+
+#endif // _GLIBCXX_EXPERIMENTAL_ANY
projects / thirdparty / gcc.git / commitdiff
