ext/alloc_traits.h
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// Allocator traits -*- C++ -*-
// Copyright (C) 2011-2013 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 ext/alloc_traits.h
* This file is a GNU extension to the Standard C++ Library.
*/
#ifndef _EXT_ALLOC_TRAITS_H
#define _EXT_ALLOC_TRAITS_H 1
#pragma GCC system_header
#if __cplusplus >= 201103L
# include <bits/move.h>
# include <bits/alloc_traits.h>
#else
# include <bits/allocator.h> // for __alloc_swap
#endif
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
template<typename> struct allocator;
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
#if __cplusplus >= 201103L
template<typename _Alloc>
struct __allocator_always_compares_equal
{ static const bool value = false; };
template<typename _Alloc>
const bool __allocator_always_compares_equal<_Alloc>::value;
template<typename _Tp>
struct __allocator_always_compares_equal<std::allocator<_Tp>>
{ static const bool value = true; };
template<typename _Tp>
const bool __allocator_always_compares_equal<std::allocator<_Tp>>::value;
template<typename, typename> struct array_allocator;
template<typename _Tp, typename _Array>
struct __allocator_always_compares_equal<array_allocator<_Tp, _Array>>
{ static const bool value = true; };
template<typename _Tp, typename _Array>
const bool
__allocator_always_compares_equal<array_allocator<_Tp, _Array>>::value;
template<typename> struct bitmap_allocator;
template<typename _Tp>
struct __allocator_always_compares_equal<bitmap_allocator<_Tp>>
{ static const bool value = true; };
template<typename _Tp>
const bool __allocator_always_compares_equal<bitmap_allocator<_Tp>>::value;
template<typename> struct malloc_allocator;
template<typename _Tp>
struct __allocator_always_compares_equal<malloc_allocator<_Tp>>
{ static const bool value = true; };
template<typename _Tp>
const bool __allocator_always_compares_equal<malloc_allocator<_Tp>>::value;
template<typename> struct mt_allocator;
template<typename _Tp>
struct __allocator_always_compares_equal<mt_allocator<_Tp>>
{ static const bool value = true; };
template<typename _Tp>
const bool __allocator_always_compares_equal<mt_allocator<_Tp>>::value;
template<typename> struct new_allocator;
template<typename _Tp>
struct __allocator_always_compares_equal<new_allocator<_Tp>>
{ static const bool value = true; };
template<typename _Tp>
const bool __allocator_always_compares_equal<new_allocator<_Tp>>::value;
template<typename> struct pool_allocator;
template<typename _Tp>
struct __allocator_always_compares_equal<pool_allocator<_Tp>>
{ static const bool value = true; };
template<typename _Tp>
const bool __allocator_always_compares_equal<pool_allocator<_Tp>>::value;
#endif
/**
* @brief Uniform interface to C++98 and C++0x allocators.
* @ingroup allocators
*/
template<typename _Alloc>
struct __alloc_traits
#if __cplusplus >= 201103L
: std::allocator_traits<_Alloc>
#endif
{
typedef _Alloc allocator_type;
#if __cplusplus >= 201103L
typedef std::allocator_traits<_Alloc> _Base_type;
typedef typename _Base_type::value_type value_type;
typedef typename _Base_type::pointer pointer;
typedef typename _Base_type::const_pointer const_pointer;
typedef typename _Base_type::size_type size_type;
typedef typename _Base_type::difference_type difference_type;
// C++0x allocators do not define reference or const_reference
typedef value_type& reference;
typedef const value_type& const_reference;
using _Base_type::allocate;
using _Base_type::deallocate;
using _Base_type::construct;
using _Base_type::destroy;
using _Base_type::max_size;
private:
template<typename _Ptr>
struct __is_custom_pointer
: std::integral_constant<bool, std::is_same<pointer, _Ptr>::value
&& !std::is_pointer<_Ptr>::value>
{ };
public:
// overload construct for non-standard pointer types
template<typename _Ptr, typename... _Args>
static typename std::enable_if<__is_custom_pointer<_Ptr>::value>::type
construct(_Alloc& __a, _Ptr __p, _Args&&... __args)
{
_Base_type::construct(__a, std::addressof(*__p),
std::forward<_Args>(__args)...);
}
// overload destroy for non-standard pointer types
template<typename _Ptr>
static typename std::enable_if<__is_custom_pointer<_Ptr>::value>::type
destroy(_Alloc& __a, _Ptr __p)
{ _Base_type::destroy(__a, std::addressof(*__p)); }
static _Alloc _S_select_on_copy(const _Alloc& __a)
{ return _Base_type::select_on_container_copy_construction(__a); }
static void _S_on_swap(_Alloc& __a, _Alloc& __b)
{ std::__alloc_on_swap(__a, __b); }
static constexpr bool _S_propagate_on_copy_assign()
{ return _Base_type::propagate_on_container_copy_assignment::value; }
static constexpr bool _S_propagate_on_move_assign()
{ return _Base_type::propagate_on_container_move_assignment::value; }
static constexpr bool _S_propagate_on_swap()
{ return _Base_type::propagate_on_container_swap::value; }
static constexpr bool _S_always_equal()
{ return __allocator_always_compares_equal<_Alloc>::value; }
static constexpr bool _S_nothrow_move()
{ return _S_propagate_on_move_assign() || _S_always_equal(); }
static constexpr bool _S_nothrow_swap()
{
using std::swap;
return !_S_propagate_on_swap()
|| noexcept(swap(std::declval<_Alloc&>(), std::declval<_Alloc&>()));
}
template<typename _Tp>
struct rebind
{ typedef typename _Base_type::template rebind_alloc<_Tp> other; };
#else
typedef typename _Alloc::pointer pointer;
typedef typename _Alloc::const_pointer const_pointer;
typedef typename _Alloc::value_type value_type;
typedef typename _Alloc::reference reference;
typedef typename _Alloc::const_reference const_reference;
typedef typename _Alloc::size_type size_type;
typedef typename _Alloc::difference_type difference_type;
static pointer
allocate(_Alloc& __a, size_type __n)
{ return __a.allocate(__n); }
static void deallocate(_Alloc& __a, pointer __p, size_type __n)
{ __a.deallocate(__p, __n); }
template<typename _Tp>
static void construct(_Alloc& __a, pointer __p, const _Tp& __arg)
{ __a.construct(__p, __arg); }
static void destroy(_Alloc& __a, pointer __p)
{ __a.destroy(__p); }
static size_type max_size(const _Alloc& __a)
{ return __a.max_size(); }
static const _Alloc& _S_select_on_copy(const _Alloc& __a) { return __a; }
static void _S_on_swap(_Alloc& __a, _Alloc& __b)
{
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 431. Swapping containers with unequal allocators.
std::__alloc_swap<_Alloc>::_S_do_it(__a, __b);
}
template<typename _Tp>
struct rebind
{ typedef typename _Alloc::template rebind<_Tp>::other other; };
#endif
};
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#endif