scoped_allocator
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// <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