allocator.h
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// Allocators -*- C++ -*-
// Copyright (C) 2001-2015 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/>.
/*
* Copyright (c) 1996-1997
* Silicon Graphics Computer Systems, Inc.
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Silicon Graphics makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*/
/** @file bits/allocator.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{memory}
*/
#ifndef _ALLOCATOR_H
#define _ALLOCATOR_H 1
#include <bits/c++allocator.h> // Define the base class to std::allocator.
#include <bits/memoryfwd.h>
#if __cplusplus >= 201103L
#include <type_traits>
#endif
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* @addtogroup allocators
* @{
*/
/// allocator<void> specialization.
template<>
class allocator<void>
{
public:
typedef size_t size_type;
typedef ptrdiff_t difference_type;
typedef void* pointer;
typedef const void* const_pointer;
typedef void value_type;
template<typename _Tp1>
struct rebind
{ typedef allocator<_Tp1> other; };
#if __cplusplus >= 201103L
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2103. std::allocator propagate_on_container_move_assignment
typedef true_type propagate_on_container_move_assignment;
template<typename _Up, typename... _Args>
void
construct(_Up* __p, _Args&&... __args)
{ ::new((void *)__p) _Up(std::forward<_Args>(__args)...); }
template<typename _Up>
void
destroy(_Up* __p) { __p->~_Up(); }
#endif
};
/**
* @brief The @a standard allocator, as per [20.4].
*
* See https://gcc.gnu.org/onlinedocs/libstdc++/manual/memory.html#std.util.memory.allocator
* for further details.
*
* @tparam _Tp Type of allocated object.
*/
template<typename _Tp>
class allocator: public __allocator_base<_Tp>
{
public:
typedef size_t size_type;
typedef ptrdiff_t difference_type;
typedef _Tp* pointer;
typedef const _Tp* const_pointer;
typedef _Tp& reference;
typedef const _Tp& const_reference;
typedef _Tp value_type;
template<typename _Tp1>
struct rebind
{ typedef allocator<_Tp1> other; };
#if __cplusplus >= 201103L
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2103. std::allocator propagate_on_container_move_assignment
typedef true_type propagate_on_container_move_assignment;
#endif
allocator() throw() { }
allocator(const allocator& __a) throw()
: __allocator_base<_Tp>(__a) { }
template<typename _Tp1>
allocator(const allocator<_Tp1>&) throw() { }
~allocator() throw() { }
// Inherit everything else.
};
template<typename _T1, typename _T2>
inline bool
operator==(const allocator<_T1>&, const allocator<_T2>&)
_GLIBCXX_USE_NOEXCEPT
{ return true; }
template<typename _Tp>
inline bool
operator==(const allocator<_Tp>&, const allocator<_Tp>&)
_GLIBCXX_USE_NOEXCEPT
{ return true; }
template<typename _T1, typename _T2>
inline bool
operator!=(const allocator<_T1>&, const allocator<_T2>&)
_GLIBCXX_USE_NOEXCEPT
{ return false; }
template<typename _Tp>
inline bool
operator!=(const allocator<_Tp>&, const allocator<_Tp>&)
_GLIBCXX_USE_NOEXCEPT
{ return false; }
/// @} group allocator
// Inhibit implicit instantiations for required instantiations,
// which are defined via explicit instantiations elsewhere.
#if _GLIBCXX_EXTERN_TEMPLATE
extern template class allocator<char>;
extern template class allocator<wchar_t>;
#endif
// Undefine.
#undef __allocator_base
// To implement Option 3 of DR 431.
template<typename _Alloc, bool = __is_empty(_Alloc)>
struct __alloc_swap
{ static void _S_do_it(_Alloc&, _Alloc&) _GLIBCXX_NOEXCEPT { } };
template<typename _Alloc>
struct __alloc_swap<_Alloc, false>
{
static void
_S_do_it(_Alloc& __one, _Alloc& __two) _GLIBCXX_NOEXCEPT
{
// Precondition: swappable allocators.
if (__one != __two)
swap(__one, __two);
}
};
// Optimize for stateless allocators.
template<typename _Alloc, bool = __is_empty(_Alloc)>
struct __alloc_neq
{
static bool
_S_do_it(const _Alloc&, const _Alloc&)
{ return false; }
};
template<typename _Alloc>
struct __alloc_neq<_Alloc, false>
{
static bool
_S_do_it(const _Alloc& __one, const _Alloc& __two)
{ return __one != __two; }
};
#if __cplusplus >= 201103L
template<typename _Tp, bool
= __or_<is_copy_constructible<typename _Tp::value_type>,
is_nothrow_move_constructible<typename _Tp::value_type>>::value>
struct __shrink_to_fit_aux
{ static bool _S_do_it(_Tp&) noexcept { return false; } };
template<typename _Tp>
struct __shrink_to_fit_aux<_Tp, true>
{
static bool
_S_do_it(_Tp& __c) noexcept
{
#if __cpp_exceptions
try
{
_Tp(__make_move_if_noexcept_iterator(__c.begin()),
__make_move_if_noexcept_iterator(__c.end()),
__c.get_allocator()).swap(__c);
return true;
}
catch(...)
{ return false; }
#else
return false;
#endif
}
};
#endif
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif
std::integral_constant
integral_constant
Definition: type_traits:69
__gnu_cxx::new_allocator
An allocator that uses global new, as per [20.4].This is precisely the allocator defined in the C++ S...
Definition: ext/alloc_traits.h:77
type_traits
std
ISO C++ entities toplevel namespace is std.
c++allocator.h
std::allocator
The standard allocator, as per [20.4].
Definition: allocator.h:101
memoryfwd.h