1 // array allocator -*- C++ -*- 2 3 // Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 4 // Free Software Foundation, Inc. 5 // 6 // This file is part of the GNU ISO C++ Library. This library is free 7 // software; you can redistribute it and/or modify it under the 8 // terms of the GNU General Public License as published by the 9 // Free Software Foundation; either version 3, or (at your option) 10 // any later version. 11 12 // This library is distributed in the hope that it will be useful, 13 // but WITHOUT ANY WARRANTY; without even the implied warranty of 14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 // GNU General Public License for more details. 16 17 // Under Section 7 of GPL version 3, you are granted additional 18 // permissions described in the GCC Runtime Library Exception, version 19 // 3.1, as published by the Free Software Foundation. 20 21 // You should have received a copy of the GNU General Public License and 22 // a copy of the GCC Runtime Library Exception along with this program; 23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 24 // <http://www.gnu.org/licenses/>. 25 26 /** @file ext/array_allocator.h 27 * This file is a GNU extension to the Standard C++ Library. 28 */ 29 30 #ifndef _ARRAY_ALLOCATOR_H 31 #define _ARRAY_ALLOCATOR_H 1 32 33 #include <bits/c++config.h> 34 #include <new> 35 #include <bits/functexcept.h> 36 #include <tr1/array> 37 #include <bits/move.h> 38 39 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) 40 { 41 _GLIBCXX_BEGIN_NAMESPACE_VERSION 42 43 using std::size_t; 44 using std::ptrdiff_t; 45 46 /// Base class. 47 template<typename _Tp> 48 class array_allocator_base 49 { 50 public: 51 typedef size_t size_type; 52 typedef ptrdiff_t difference_type; 53 typedef _Tp* pointer; 54 typedef const _Tp* const_pointer; 55 typedef _Tp& reference; 56 typedef const _Tp& const_reference; 57 typedef _Tp value_type; 58 59 pointer 60 address(reference __x) const _GLIBCXX_NOEXCEPT 61 { return std::__addressof(__x); } 62 63 const_pointer 64 address(const_reference __x) const _GLIBCXX_NOEXCEPT 65 { return std::__addressof(__x); } 66 67 void 68 deallocate(pointer, size_type) 69 { 70 // Does nothing. 71 } 72 73 size_type 74 max_size() const _GLIBCXX_USE_NOEXCEPT 75 { return size_t(-1) / sizeof(_Tp); } 76 77 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 78 template<typename _Up, typename... _Args> 79 void 80 construct(_Up* __p, _Args&&... __args) 81 { ::new((void *)__p) _Up(std::forward<_Args>(__args)...); } 82 83 template<typename _Up> 84 void 85 destroy(_Up* __p) { __p->~_Up(); } 86 #else 87 // _GLIBCXX_RESOLVE_LIB_DEFECTS 88 // 402. wrong new expression in [some_] allocator::construct 89 void 90 construct(pointer __p, const _Tp& __val) 91 { ::new((void *)__p) value_type(__val); } 92 93 void 94 destroy(pointer __p) { __p->~_Tp(); } 95 #endif 96 }; 97 98 /** 99 * @brief An allocator that uses previously allocated memory. 100 * This memory can be externally, globally, or otherwise allocated. 101 * @ingroup allocators 102 */ 103 template<typename _Tp, typename _Array = std::tr1::array<_Tp, 1> > 104 class array_allocator : public array_allocator_base<_Tp> 105 { 106 public: 107 typedef size_t size_type; 108 typedef ptrdiff_t difference_type; 109 typedef _Tp* pointer; 110 typedef const _Tp* const_pointer; 111 typedef _Tp& reference; 112 typedef const _Tp& const_reference; 113 typedef _Tp value_type; 114 typedef _Array array_type; 115 116 private: 117 array_type* _M_array; 118 size_type _M_used; 119 120 public: 121 template<typename _Tp1, typename _Array1 = _Array> 122 struct rebind 123 { typedef array_allocator<_Tp1, _Array1> other; }; 124 125 array_allocator(array_type* __array = 0) _GLIBCXX_USE_NOEXCEPT 126 : _M_array(__array), _M_used(size_type()) { } 127 128 array_allocator(const array_allocator& __o) _GLIBCXX_USE_NOEXCEPT 129 : _M_array(__o._M_array), _M_used(__o._M_used) { } 130 131 template<typename _Tp1, typename _Array1> 132 array_allocator(const array_allocator<_Tp1, _Array1>&) 133 _GLIBCXX_USE_NOEXCEPT 134 : _M_array(0), _M_used(size_type()) { } 135 136 ~array_allocator() _GLIBCXX_USE_NOEXCEPT { } 137 138 pointer 139 allocate(size_type __n, const void* = 0) 140 { 141 if (_M_array == 0 || _M_used + __n > _M_array->size()) 142 std::__throw_bad_alloc(); 143 pointer __ret = _M_array->begin() + _M_used; 144 _M_used += __n; 145 return __ret; 146 } 147 }; 148 149 template<typename _Tp, typename _Array> 150 inline bool 151 operator==(const array_allocator<_Tp, _Array>&, 152 const array_allocator<_Tp, _Array>&) 153 { return true; } 154 155 template<typename _Tp, typename _Array> 156 inline bool 157 operator!=(const array_allocator<_Tp, _Array>&, 158 const array_allocator<_Tp, _Array>&) 159 { return false; } 160 161 _GLIBCXX_END_NAMESPACE_VERSION 162 } // namespace 163 164 #endif 165
