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Edit File: scoped_allocator
// <scoped_allocator> -*- C++ -*- // Copyright (C) 2011-2021 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 include/scoped_allocator * This is a Standard C++ Library header. * @ingroup allocators */ #ifndef _SCOPED_ALLOCATOR #define _SCOPED_ALLOCATOR 1 #pragma GCC system_header #if __cplusplus < 201103L # include <bits/c++0x_warning.h> #else #include <tuple> #include <bits/alloc_traits.h> #include <bits/stl_pair.h> #include <bits/uses_allocator.h> #if __cplusplus > 201703L # include <bits/uses_allocator_args.h> #endif namespace std _GLIBCXX_VISIBILITY(default) { _GLIBCXX_BEGIN_NAMESPACE_VERSION /** * @addtogroup allocators * @{ */ template<typename _OuterAlloc, typename... _InnerAllocs> class scoped_allocator_adaptor; /// @cond undocumented template<typename _Alloc> using __outer_allocator_t = decltype(std::declval<_Alloc>().outer_allocator()); template<typename _Alloc, typename = void> struct __outermost_type { using type = _Alloc; static type& _S_outermost(_Alloc& __a) { return __a; } }; template<typename _Alloc> struct __outermost_type<_Alloc, __void_t<__outer_allocator_t<_Alloc>>> : __outermost_type< typename remove_reference<__outer_allocator_t<_Alloc>>::type > { using __base = __outermost_type< typename remove_reference<__outer_allocator_t<_Alloc>>::type >; static typename __base::type& _S_outermost(_Alloc& __a) { return __base::_S_outermost(__a.outer_allocator()); } }; // Implementation of the OUTERMOST pseudofunction template<typename _Alloc> inline typename __outermost_type<_Alloc>::type& __outermost(_Alloc& __a) { return __outermost_type<_Alloc>::_S_outermost(__a); } template<typename...> struct __inner_type_impl; template<typename _Outer> struct __inner_type_impl<_Outer> { typedef scoped_allocator_adaptor<_Outer> __type; __inner_type_impl() = default; __inner_type_impl(const __inner_type_impl&) = default; __inner_type_impl(__inner_type_impl&&) = default; __inner_type_impl& operator=(const __inner_type_impl&) = default; __inner_type_impl& operator=(__inner_type_impl&&) = default; template<typename _Alloc> __inner_type_impl(const __inner_type_impl<_Alloc>& __other) { } template<typename _Alloc> __inner_type_impl(__inner_type_impl<_Alloc>&& __other) { } __type& _M_get(__type* __p) noexcept { return *__p; } const __type& _M_get(const __type* __p) const noexcept { return *__p; } tuple<> _M_tie() const noexcept { return tuple<>(); } bool operator==(const __inner_type_impl&) const noexcept { return true; } }; template<typename _Outer, typename _InnerHead, typename... _InnerTail> struct __inner_type_impl<_Outer, _InnerHead, _InnerTail...> { typedef scoped_allocator_adaptor<_InnerHead, _InnerTail...> __type; __inner_type_impl() = default; __inner_type_impl(const __inner_type_impl&) = default; __inner_type_impl(__inner_type_impl&&) = default; __inner_type_impl& operator=(const __inner_type_impl&) = default; __inner_type_impl& operator=(__inner_type_impl&&) = default; template<typename... _Allocs> __inner_type_impl(const __inner_type_impl<_Allocs...>& __other) : _M_inner(__other._M_inner) { } template<typename... _Allocs> __inner_type_impl(__inner_type_impl<_Allocs...>&& __other) : _M_inner(std::move(__other._M_inner)) { } template<typename... _Args> explicit __inner_type_impl(_Args&&... __args) : _M_inner(std::forward<_Args>(__args)...) { } __type& _M_get(void*) noexcept { return _M_inner; } const __type& _M_get(const void*) const noexcept { return _M_inner; } tuple<const _InnerHead&, const _InnerTail&...> _M_tie() const noexcept { return _M_inner._M_tie(); } bool operator==(const __inner_type_impl& __other) const noexcept { return _M_inner == __other._M_inner; } private: template<typename...> friend class __inner_type_impl; template<typename, typename...> friend class scoped_allocator_adaptor; __type _M_inner; }; /// @endcond /// An adaptor to recursively pass an allocator to the objects it constructs template<typename _OuterAlloc, typename... _InnerAllocs> class scoped_allocator_adaptor : public _OuterAlloc { typedef allocator_traits<_OuterAlloc> __traits; typedef __inner_type_impl<_OuterAlloc, _InnerAllocs...> __inner_type; __inner_type _M_inner; template<typename _Outer, typename... _Inner> friend class scoped_allocator_adaptor; template<typename...> friend class __inner_type_impl; tuple<const _OuterAlloc&, const _InnerAllocs&...> _M_tie() const noexcept { return std::tuple_cat(std::tie(outer_allocator()), _M_inner._M_tie()); } template<typename _Alloc> using __outermost_alloc_traits = allocator_traits<typename __outermost_type<_Alloc>::type>; #if ! __cpp_lib_make_obj_using_allocator template<typename _Tp, typename... _Args> void _M_construct(__uses_alloc0, _Tp* __p, _Args&&... __args) { typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; _O_traits::construct(__outermost(*this), __p, std::forward<_Args>(__args)...); } typedef __uses_alloc1<typename __inner_type::__type> __uses_alloc1_; typedef __uses_alloc2<typename __inner_type::__type> __uses_alloc2_; template<typename _Tp, typename... _Args> void _M_construct(__uses_alloc1_, _Tp* __p, _Args&&... __args) { typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; _O_traits::construct(__outermost(*this), __p, allocator_arg, inner_allocator(), std::forward<_Args>(__args)...); } template<typename _Tp, typename... _Args> void _M_construct(__uses_alloc2_, _Tp* __p, _Args&&... __args) { typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; _O_traits::construct(__outermost(*this), __p, std::forward<_Args>(__args)..., inner_allocator()); } #endif // ! make_obj_using_allocator template<typename _Alloc> static _Alloc _S_select_on_copy(const _Alloc& __a) { typedef allocator_traits<_Alloc> __a_traits; return __a_traits::select_on_container_copy_construction(__a); } template<std::size_t... _Indices> scoped_allocator_adaptor(tuple<const _OuterAlloc&, const _InnerAllocs&...> __refs, _Index_tuple<_Indices...>) : _OuterAlloc(_S_select_on_copy(std::get<0>(__refs))), _M_inner(_S_select_on_copy(std::get<_Indices+1>(__refs))...) { } // Used to constrain constructors to disallow invalid conversions. template<typename _Alloc> using _Constructible = typename enable_if< is_constructible<_OuterAlloc, _Alloc>::value >::type; // _GLIBCXX_RESOLVE_LIB_DEFECTS // 2975. Missing case for pair construction in scoped [...] allocators template<typename _Tp> struct __not_pair { using type = void; }; template<typename _Tp, typename _Up> struct __not_pair<pair<_Tp, _Up>> { }; public: typedef _OuterAlloc outer_allocator_type; typedef typename __inner_type::__type inner_allocator_type; typedef typename __traits::value_type value_type; typedef typename __traits::size_type size_type; typedef typename __traits::difference_type difference_type; typedef typename __traits::pointer pointer; typedef typename __traits::const_pointer const_pointer; typedef typename __traits::void_pointer void_pointer; typedef typename __traits::const_void_pointer const_void_pointer; typedef typename __or_< typename __traits::propagate_on_container_copy_assignment, typename allocator_traits<_InnerAllocs>:: propagate_on_container_copy_assignment...>::type propagate_on_container_copy_assignment; typedef typename __or_< typename __traits::propagate_on_container_move_assignment, typename allocator_traits<_InnerAllocs>:: propagate_on_container_move_assignment...>::type propagate_on_container_move_assignment; typedef typename __or_< typename __traits::propagate_on_container_swap, typename allocator_traits<_InnerAllocs>:: propagate_on_container_swap...>::type propagate_on_container_swap; typedef typename __and_< typename __traits::is_always_equal, typename allocator_traits<_InnerAllocs>::is_always_equal...>::type is_always_equal; template <class _Tp> struct rebind { typedef scoped_allocator_adaptor< typename __traits::template rebind_alloc<_Tp>, _InnerAllocs...> other; }; scoped_allocator_adaptor() : _OuterAlloc(), _M_inner() { } template<typename _Outer2, typename = _Constructible<_Outer2>> scoped_allocator_adaptor(_Outer2&& __outer, const _InnerAllocs&... __inner) : _OuterAlloc(std::forward<_Outer2>(__outer)), _M_inner(__inner...) { } scoped_allocator_adaptor(const scoped_allocator_adaptor& __other) : _OuterAlloc(__other.outer_allocator()), _M_inner(__other._M_inner) { } scoped_allocator_adaptor(scoped_allocator_adaptor&& __other) : _OuterAlloc(std::move(__other.outer_allocator())), _M_inner(std::move(__other._M_inner)) { } template<typename _Outer2, typename = _Constructible<const _Outer2&>> scoped_allocator_adaptor( const scoped_allocator_adaptor<_Outer2, _InnerAllocs...>& __other) : _OuterAlloc(__other.outer_allocator()), _M_inner(__other._M_inner) { } template<typename _Outer2, typename = _Constructible<_Outer2>> scoped_allocator_adaptor( scoped_allocator_adaptor<_Outer2, _InnerAllocs...>&& __other) : _OuterAlloc(std::move(__other.outer_allocator())), _M_inner(std::move(__other._M_inner)) { } scoped_allocator_adaptor& operator=(const scoped_allocator_adaptor&) = default; scoped_allocator_adaptor& operator=(scoped_allocator_adaptor&&) = default; inner_allocator_type& inner_allocator() noexcept { return _M_inner._M_get(this); } const inner_allocator_type& inner_allocator() const noexcept { return _M_inner._M_get(this); } outer_allocator_type& outer_allocator() noexcept { return static_cast<_OuterAlloc&>(*this); } const outer_allocator_type& outer_allocator() const noexcept { return static_cast<const _OuterAlloc&>(*this); } _GLIBCXX_NODISCARD pointer allocate(size_type __n) { return __traits::allocate(outer_allocator(), __n); } _GLIBCXX_NODISCARD pointer allocate(size_type __n, const_void_pointer __hint) { return __traits::allocate(outer_allocator(), __n, __hint); } void deallocate(pointer __p, size_type __n) { return __traits::deallocate(outer_allocator(), __p, __n); } size_type max_size() const { return __traits::max_size(outer_allocator()); } #if ! __cpp_lib_make_obj_using_allocator template<typename _Tp, typename... _Args> typename __not_pair<_Tp>::type construct(_Tp* __p, _Args&&... __args) { auto& __inner = inner_allocator(); auto __use_tag = std::__use_alloc<_Tp, inner_allocator_type, _Args...>(__inner); _M_construct(__use_tag, __p, std::forward<_Args>(__args)...); } template<typename _T1, typename _T2, typename... _Args1, typename... _Args2> void construct(pair<_T1, _T2>* __p, piecewise_construct_t, tuple<_Args1...> __x, tuple<_Args2...> __y) { // _GLIBCXX_RESOLVE_LIB_DEFECTS // 2203. wrong argument types for piecewise construction auto& __inner = inner_allocator(); auto __x_use_tag = std::__use_alloc<_T1, inner_allocator_type, _Args1...>(__inner); auto __y_use_tag = std::__use_alloc<_T2, inner_allocator_type, _Args2...>(__inner); typename _Build_index_tuple<sizeof...(_Args1)>::__type __x_indices; typename _Build_index_tuple<sizeof...(_Args2)>::__type __y_indices; typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; _O_traits::construct(__outermost(*this), __p, piecewise_construct, _M_construct_p(__x_use_tag, __x_indices, __x), _M_construct_p(__y_use_tag, __y_indices, __y)); } template<typename _T1, typename _T2> void construct(pair<_T1, _T2>* __p) { construct(__p, piecewise_construct, tuple<>(), tuple<>()); } template<typename _T1, typename _T2, typename _Up, typename _Vp> void construct(pair<_T1, _T2>* __p, _Up&& __u, _Vp&& __v) { construct(__p, piecewise_construct, std::forward_as_tuple(std::forward<_Up>(__u)), std::forward_as_tuple(std::forward<_Vp>(__v))); } template<typename _T1, typename _T2, typename _Up, typename _Vp> void construct(pair<_T1, _T2>* __p, const pair<_Up, _Vp>& __x) { construct(__p, piecewise_construct, std::forward_as_tuple(__x.first), std::forward_as_tuple(__x.second)); } template<typename _T1, typename _T2, typename _Up, typename _Vp> void construct(pair<_T1, _T2>* __p, pair<_Up, _Vp>&& __x) { construct(__p, piecewise_construct, std::forward_as_tuple(std::forward<_Up>(__x.first)), std::forward_as_tuple(std::forward<_Vp>(__x.second))); } #else // make_obj_using_allocator template<typename _Tp, typename... _Args> __attribute__((__nonnull__)) void construct(_Tp* __p, _Args&&... __args) { typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; std::apply([__p, this](auto&&... __newargs) { _O_traits::construct(__outermost(*this), __p, std::forward<decltype(__newargs)>(__newargs)...); }, uses_allocator_construction_args<_Tp>(inner_allocator(), std::forward<_Args>(__args)...)); } #endif template<typename _Tp> void destroy(_Tp* __p) { typedef __outermost_alloc_traits<scoped_allocator_adaptor> _O_traits; _O_traits::destroy(__outermost(*this), __p); } scoped_allocator_adaptor select_on_container_copy_construction() const { typedef typename _Build_index_tuple<sizeof...(_InnerAllocs)>::__type _Indices; return scoped_allocator_adaptor(_M_tie(), _Indices()); } template <typename _OutA1, typename _OutA2, typename... _InA> friend bool operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a, const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept; private: #if ! __cpp_lib_make_obj_using_allocator template<typename _Ind, typename... _Args> tuple<_Args&&...> _M_construct_p(__uses_alloc0, _Ind, tuple<_Args...>& __t) { return std::move(__t); } template<size_t... _Ind, typename... _Args> tuple<allocator_arg_t, inner_allocator_type&, _Args&&...> _M_construct_p(__uses_alloc1_, _Index_tuple<_Ind...>, tuple<_Args...>& __t) { return { allocator_arg, inner_allocator(), std::get<_Ind>(std::move(__t))... }; } template<size_t... _Ind, typename... _Args> tuple<_Args&&..., inner_allocator_type&> _M_construct_p(__uses_alloc2_, _Index_tuple<_Ind...>, tuple<_Args...>& __t) { return { std::get<_Ind>(std::move(__t))..., inner_allocator() }; } #endif // ! make_obj_using_allocator }; /// @related std::scoped_allocator_adaptor template <typename _OutA1, typename _OutA2, typename... _InA> inline bool operator==(const scoped_allocator_adaptor<_OutA1, _InA...>& __a, const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept { return __a.outer_allocator() == __b.outer_allocator() && __a._M_inner == __b._M_inner; } #if __cpp_impl_three_way_comparison < 201907L /// @related std::scoped_allocator_adaptor template <typename _OutA1, typename _OutA2, typename... _InA> inline bool operator!=(const scoped_allocator_adaptor<_OutA1, _InA...>& __a, const scoped_allocator_adaptor<_OutA2, _InA...>& __b) noexcept { return !(__a == __b); } #endif /// @} _GLIBCXX_END_NAMESPACE_VERSION } // namespace #endif // C++11 #endif // _SCOPED_ALLOCATOR