1// Allocator that wraps operator new -*- C++ -*- 2 3// Copyright (C) 2001-2014 Free Software Foundation, Inc. 4// 5// This file is part of the GNU ISO C++ Library. This library is free 6// software; you can redistribute it and/or modify it under the 7// terms of the GNU General Public License as published by the 8// Free Software Foundation; either version 3, or (at your option) 9// any later version. 10 11// This library is distributed in the hope that it will be useful, 12// but WITHOUT ANY WARRANTY; without even the implied warranty of 13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14// GNU General Public License for more details. 15 16// Under Section 7 of GPL version 3, you are granted additional 17// permissions described in the GCC Runtime Library Exception, version 18// 3.1, as published by the Free Software Foundation. 19 20// You should have received a copy of the GNU General Public License and 21// a copy of the GCC Runtime Library Exception along with this program; 22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23// <http://www.gnu.org/licenses/>. 24 25/** @file ext/new_allocator.h 26 * This file is a GNU extension to the Standard C++ Library. 27 */ 28 29#ifndef _NEW_ALLOCATOR_H 30#define _NEW_ALLOCATOR_H 1 31 32#include <bits/c++config.h> 33#include <new> 34#include <bits/functexcept.h> 35#include <bits/move.h> 36#if __cplusplus >= 201103L 37#include <type_traits> 38#endif 39 40namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) 41{ 42_GLIBCXX_BEGIN_NAMESPACE_VERSION 43 44 using std::size_t; 45 using std::ptrdiff_t; 46 47 /** 48 * @brief An allocator that uses global new, as per [20.4]. 49 * @ingroup allocators 50 * 51 * This is precisely the allocator defined in the C++ Standard. 52 * - all allocation calls operator new 53 * - all deallocation calls operator delete 54 * 55 * @tparam _Tp Type of allocated object. 56 */ 57 template<typename _Tp> 58 class new_allocator 59 { 60 public: 61 typedef size_t size_type; 62 typedef ptrdiff_t difference_type; 63 typedef _Tp* pointer; 64 typedef const _Tp* const_pointer; 65 typedef _Tp& reference; 66 typedef const _Tp& const_reference; 67 typedef _Tp value_type; 68 69 template<typename _Tp1> 70 struct rebind 71 { typedef new_allocator<_Tp1> other; }; 72 73#if __cplusplus >= 201103L 74 // _GLIBCXX_RESOLVE_LIB_DEFECTS 75 // 2103. propagate_on_container_move_assignment 76 typedef std::true_type propagate_on_container_move_assignment; 77#endif 78 79 new_allocator() _GLIBCXX_USE_NOEXCEPT { } 80 81 new_allocator(const new_allocator&) _GLIBCXX_USE_NOEXCEPT { } 82 83 template<typename _Tp1> 84 new_allocator(const new_allocator<_Tp1>&) _GLIBCXX_USE_NOEXCEPT { } 85 86 ~new_allocator() _GLIBCXX_USE_NOEXCEPT { } 87 88 pointer 89 address(reference __x) const _GLIBCXX_NOEXCEPT 90 { return std::__addressof(__x); } 91 92 const_pointer 93 address(const_reference __x) const _GLIBCXX_NOEXCEPT 94 { return std::__addressof(__x); } 95 96 // NB: __n is permitted to be 0. The C++ standard says nothing 97 // about what the return value is when __n == 0. 98 pointer 99 allocate(size_type __n, const void* = 0) 100 { 101 if (__n > this->max_size()) 102 std::__throw_bad_alloc(); 103 104 return static_cast<_Tp*>(::operator new(__n * sizeof(_Tp))); 105 } 106 107#ifdef __GXX_DELETE_WITH_SIZE__ 108 // __p is not permitted to be a null pointer. 109 void 110 deallocate(pointer __p, size_type __t) 111 { ::operator delete(__p, __t * sizeof(_Tp)); } 112#else 113 // __p is not permitted to be a null pointer. 114 void 115 deallocate(pointer __p, size_type) 116 { ::operator delete(__p); } 117#endif 118 119 size_type 120 max_size() const _GLIBCXX_USE_NOEXCEPT 121 { return size_t(-1) / sizeof(_Tp); } 122 123#if __cplusplus >= 201103L 124 template<typename _Up, typename... _Args> 125 void 126 construct(_Up* __p, _Args&&... __args) 127 { ::new((void *)__p) _Up(std::forward<_Args>(__args)...); } 128 129 template<typename _Up> 130 void 131 destroy(_Up* __p) { __p->~_Up(); } 132#else 133 // _GLIBCXX_RESOLVE_LIB_DEFECTS 134 // 402. wrong new expression in [some_] allocator::construct 135 void 136 construct(pointer __p, const _Tp& __val) 137 { ::new((void *)__p) _Tp(__val); } 138 139 void 140 destroy(pointer __p) { __p->~_Tp(); } 141#endif 142 }; 143 144 template<typename _Tp> 145 inline bool 146 operator==(const new_allocator<_Tp>&, const new_allocator<_Tp>&) 147 { return true; } 148 149 template<typename _Tp> 150 inline bool 151 operator!=(const new_allocator<_Tp>&, const new_allocator<_Tp>&) 152 { return false; } 153 154_GLIBCXX_END_NAMESPACE_VERSION 155} // namespace 156 157#endif 158