1 // Allocator traits -*- C++ -*- 2 3 // Copyright (C) 2011-2013 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/alloc_traits.h 26 * This file is a GNU extension to the Standard C++ Library. 27 */ 28 29 #ifndef _EXT_ALLOC_TRAITS_H 30 #define _EXT_ALLOC_TRAITS_H 1 31 32 #pragma GCC system_header 33 34 #if __cplusplus >= 201103L 35 # include <bits/move.h> 36 # include <bits/alloc_traits.h> 37 #else 38 # include <bits/allocator.h> // for __alloc_swap 39 #endif 40 41 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) 42 { 43 _GLIBCXX_BEGIN_NAMESPACE_VERSION 44 45 #if __cplusplus >= 201103L 46 template<typename _Alloc> 47 struct __allocator_always_compares_equal 48 { static const bool value = false; }; 49 50 template<typename _Alloc> 51 const bool __allocator_always_compares_equal<_Alloc>::value; 52 53 template<typename _Tp> 54 struct __allocator_always_compares_equal<std::allocator<_Tp>> 55 { static const bool value = true; }; 56 57 template<typename _Tp> 58 const bool __allocator_always_compares_equal<std::allocator<_Tp>>::value; 59 60 template<typename, typename> struct array_allocator; 61 62 template<typename _Tp, typename _Array> 63 struct __allocator_always_compares_equal<array_allocator<_Tp, _Array>> 64 { static const bool value = true; }; 65 66 template<typename _Tp, typename _Array> 67 const bool 68 __allocator_always_compares_equal<array_allocator<_Tp, _Array>>::value; 69 70 template<typename> struct bitmap_allocator; 71 72 template<typename _Tp> 73 struct __allocator_always_compares_equal<bitmap_allocator<_Tp>> 74 { static const bool value = true; }; 75 76 template<typename _Tp> 77 const bool __allocator_always_compares_equal<bitmap_allocator<_Tp>>::value; 78 79 template<typename> struct malloc_allocator; 80 81 template<typename _Tp> 82 struct __allocator_always_compares_equal<malloc_allocator<_Tp>> 83 { static const bool value = true; }; 84 85 template<typename _Tp> 86 const bool __allocator_always_compares_equal<malloc_allocator<_Tp>>::value; 87 88 template<typename> struct mt_allocator; 89 90 template<typename _Tp> 91 struct __allocator_always_compares_equal<mt_allocator<_Tp>> 92 { static const bool value = true; }; 93 94 template<typename _Tp> 95 const bool __allocator_always_compares_equal<mt_allocator<_Tp>>::value; 96 97 template<typename> struct new_allocator; 98 99 template<typename _Tp> 100 struct __allocator_always_compares_equal<new_allocator<_Tp>> 101 { static const bool value = true; }; 102 103 template<typename _Tp> 104 const bool __allocator_always_compares_equal<new_allocator<_Tp>>::value; 105 106 template<typename> struct pool_allocator; 107 108 template<typename _Tp> 109 struct __allocator_always_compares_equal<pool_allocator<_Tp>> 110 { static const bool value = true; }; 111 112 template<typename _Tp> 113 const bool __allocator_always_compares_equal<pool_allocator<_Tp>>::value; 114 #endif 115 116 /** 117 * @brief Uniform interface to C++98 and C++0x allocators. 118 * @ingroup allocators 119 */ 120 template<typename _Alloc> 121 struct __alloc_traits 122 #if __cplusplus >= 201103L 123 : std::allocator_traits<_Alloc> 124 #endif 125 { 126 typedef _Alloc allocator_type; 127 #if __cplusplus >= 201103L 128 typedef std::allocator_traits<_Alloc> _Base_type; 129 typedef typename _Base_type::value_type value_type; 130 typedef typename _Base_type::pointer pointer; 131 typedef typename _Base_type::const_pointer const_pointer; 132 typedef typename _Base_type::size_type size_type; 133 typedef typename _Base_type::difference_type difference_type; 134 // C++0x allocators do not define reference or const_reference 135 typedef value_type& reference; 136 typedef const value_type& const_reference; 137 using _Base_type::allocate; 138 using _Base_type::deallocate; 139 using _Base_type::construct; 140 using _Base_type::destroy; 141 using _Base_type::max_size; 142 143 private: 144 template<typename _Ptr> 145 struct __is_custom_pointer 146 : std::integral_constant<bool, std::is_same<pointer, _Ptr>::value 147 && !std::is_pointer<_Ptr>::value> 148 { }; 149 150 public: 151 // overload construct for non-standard pointer types 152 template<typename _Ptr, typename... _Args> 153 static typename std::enable_if<__is_custom_pointer<_Ptr>::value>::type 154 construct(_Alloc& __a, _Ptr __p, _Args&&... __args) 155 { 156 _Base_type::construct(__a, std::addressof(*__p), 157 std::forward<_Args>(__args)...); 158 } 159 160 // overload destroy for non-standard pointer types 161 template<typename _Ptr> 162 static typename std::enable_if<__is_custom_pointer<_Ptr>::value>::type 163 destroy(_Alloc& __a, _Ptr __p) 164 { _Base_type::destroy(__a, std::addressof(*__p)); } 165 166 static _Alloc _S_select_on_copy(const _Alloc& __a) 167 { return _Base_type::select_on_container_copy_construction(__a); } 168 169 static void _S_on_swap(_Alloc& __a, _Alloc& __b) 170 { std::__alloc_on_swap(__a, __b); } 171 172 static constexpr bool _S_propagate_on_copy_assign() 173 { return _Base_type::propagate_on_container_copy_assignment::value; } 174 175 static constexpr bool _S_propagate_on_move_assign() 176 { return _Base_type::propagate_on_container_move_assignment::value; } 177 178 static constexpr bool _S_propagate_on_swap() 179 { return _Base_type::propagate_on_container_swap::value; } 180 181 static constexpr bool _S_always_equal() 182 { return __allocator_always_compares_equal<_Alloc>::value; } 183 184 static constexpr bool _S_nothrow_move() 185 { return _S_propagate_on_move_assign() || _S_always_equal(); } 186 187 static constexpr bool _S_nothrow_swap() 188 { 189 using std::swap; 190 return !_S_propagate_on_swap() 191 || noexcept(swap(std::declval<_Alloc&>(), std::declval<_Alloc&>())); 192 } 193 194 template<typename _Tp> 195 struct rebind 196 { typedef typename _Base_type::template rebind_alloc<_Tp> other; }; 197 #else 198 199 typedef typename _Alloc::pointer pointer; 200 typedef typename _Alloc::const_pointer const_pointer; 201 typedef typename _Alloc::value_type value_type; 202 typedef typename _Alloc::reference reference; 203 typedef typename _Alloc::const_reference const_reference; 204 typedef typename _Alloc::size_type size_type; 205 typedef typename _Alloc::difference_type difference_type; 206 207 static pointer 208 allocate(_Alloc& __a, size_type __n) 209 { return __a.allocate(__n); } 210 211 static void deallocate(_Alloc& __a, pointer __p, size_type __n) 212 { __a.deallocate(__p, __n); } 213 214 template<typename _Tp> 215 static void construct(_Alloc& __a, pointer __p, const _Tp& __arg) 216 { __a.construct(__p, __arg); } 217 218 static void destroy(_Alloc& __a, pointer __p) 219 { __a.destroy(__p); } 220 221 static size_type max_size(const _Alloc& __a) 222 { return __a.max_size(); } 223 224 static const _Alloc& _S_select_on_copy(const _Alloc& __a) { return __a; } 225 226 static void _S_on_swap(_Alloc& __a, _Alloc& __b) 227 { 228 // _GLIBCXX_RESOLVE_LIB_DEFECTS 229 // 431. Swapping containers with unequal allocators. 230 std::__alloc_swap<_Alloc>::_S_do_it(__a, __b); 231 } 232 233 template<typename _Tp> 234 struct rebind 235 { typedef typename _Alloc::template rebind<_Tp>::other other; }; 236 #endif 237 }; 238 239 _GLIBCXX_END_NAMESPACE_VERSION 240 } // namespace std 241 242 #endif 243
