1// array allocator -*- C++ -*- 2 3// Copyright (C) 2004-2019 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/array_allocator.h 26 * This file is a GNU extension to the Standard C++ Library. 27 */ 28 29#ifndef _ARRAY_ALLOCATOR_H 30#define _ARRAY_ALLOCATOR_H 1 31 32#include <bits/c++config.h> 33#include <new> 34#include <bits/functexcept.h> 35#include <tr1/array> 36#include <bits/move.h> 37#if __cplusplus >= 201103L 38#include <type_traits> 39#endif 40 41// Suppress deprecated warning for this file. 42#pragma GCC diagnostic push 43#pragma GCC diagnostic ignored "-Wdeprecated-declarations" 44 45namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) 46{ 47_GLIBCXX_BEGIN_NAMESPACE_VERSION 48 49 using std::size_t; 50 using std::ptrdiff_t; 51 52 /// Base class. 53 template<typename _Tp> 54 class array_allocator_base 55 { 56 public: 57 typedef size_t size_type; 58 typedef ptrdiff_t difference_type; 59 typedef _Tp* pointer; 60 typedef const _Tp* const_pointer; 61 typedef _Tp& reference; 62 typedef const _Tp& const_reference; 63 typedef _Tp value_type; 64 65 pointer 66 address(reference __x) const _GLIBCXX_NOEXCEPT 67 { return std::__addressof(__x); } 68 69 const_pointer 70 address(const_reference __x) const _GLIBCXX_NOEXCEPT 71 { return std::__addressof(__x); } 72 73 void 74 deallocate(pointer, size_type) 75 { 76 // Does nothing. 77 } 78 79 size_type 80 max_size() const _GLIBCXX_USE_NOEXCEPT 81 { return size_t(-1) / sizeof(_Tp); } 82 83#if __cplusplus >= 201103L 84 template<typename _Up, typename... _Args> 85 void 86 construct(_Up* __p, _Args&&... __args) 87 { ::new((void *)__p) _Up(std::forward<_Args>(__args)...); } 88 89 template<typename _Up> 90 void 91 destroy(_Up* __p) { __p->~_Up(); } 92#else 93 // _GLIBCXX_RESOLVE_LIB_DEFECTS 94 // 402. wrong new expression in [some_] allocator::construct 95 void 96 construct(pointer __p, const _Tp& __val) 97 { ::new((void *)__p) value_type(__val); } 98 99 void 100 destroy(pointer __p) { __p->~_Tp(); } 101#endif 102 } _GLIBCXX_DEPRECATED; 103 104 /** 105 * @brief An allocator that uses previously allocated memory. 106 * This memory can be externally, globally, or otherwise allocated. 107 * @ingroup allocators 108 */ 109 template<typename _Tp, typename _Array = std::tr1::array<_Tp, 1> > 110 class array_allocator : public array_allocator_base<_Tp> 111 { 112 public: 113 typedef size_t size_type; 114 typedef ptrdiff_t difference_type; 115 typedef _Tp* pointer; 116 typedef const _Tp* const_pointer; 117 typedef _Tp& reference; 118 typedef const _Tp& const_reference; 119 typedef _Tp value_type; 120 typedef _Array array_type; 121 122#if __cplusplus >= 201103L 123 // _GLIBCXX_RESOLVE_LIB_DEFECTS 124 // 2103. std::allocator propagate_on_container_move_assignment 125 typedef std::true_type propagate_on_container_move_assignment; 126 127 typedef std::true_type is_always_equal; 128#endif 129 130 private: 131 array_type* _M_array; 132 size_type _M_used; 133 134 public: 135 template<typename _Tp1, typename _Array1 = _Array> 136 struct rebind 137 { 138 typedef array_allocator<_Tp1, _Array1> other _GLIBCXX_DEPRECATED; 139 } _GLIBCXX_DEPRECATED; 140 141 array_allocator(array_type* __array = 0) _GLIBCXX_USE_NOEXCEPT 142 : _M_array(__array), _M_used(size_type()) { } 143 144 array_allocator(const array_allocator& __o) _GLIBCXX_USE_NOEXCEPT 145 : _M_array(__o._M_array), _M_used(__o._M_used) { } 146 147 template<typename _Tp1, typename _Array1> 148 array_allocator(const array_allocator<_Tp1, _Array1>&) 149 _GLIBCXX_USE_NOEXCEPT 150 : _M_array(0), _M_used(size_type()) { } 151 152 ~array_allocator() _GLIBCXX_USE_NOEXCEPT { } 153 154 _GLIBCXX_NODISCARD pointer 155 allocate(size_type __n, const void* = 0) 156 { 157 if (_M_array == 0 || _M_used + __n > _M_array->size()) 158 std::__throw_bad_alloc(); 159 pointer __ret = _M_array->begin() + _M_used; 160 _M_used += __n; 161 return __ret; 162 } 163 } _GLIBCXX_DEPRECATED; 164 165 template<typename _Tp, typename _Array> 166 inline bool 167 operator==(const array_allocator<_Tp, _Array>&, 168 const array_allocator<_Tp, _Array>&) 169 { return true; } 170 171 template<typename _Tp, typename _Array> 172 inline bool 173 operator!=(const array_allocator<_Tp, _Array>&, 174 const array_allocator<_Tp, _Array>&) 175 { return false; } 176 177_GLIBCXX_END_NAMESPACE_VERSION 178} // namespace 179 180#pragma GCC diagnostic pop 181 182#endif 183