1 // array allocator -*- C++ -*- 2 3 // Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 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 { return std::__addressof(__x); } 61 62 const_pointer 63 address(const_reference __x) const { return std::__addressof(__x); } 64 65 void 66 deallocate(pointer, size_type) 67 { 68 // Does nothing. 69 } 70 71 size_type 72 max_size() const throw() 73 { return size_t(-1) / sizeof(_Tp); } 74 75 // _GLIBCXX_RESOLVE_LIB_DEFECTS 76 // 402. wrong new expression in [some_] allocator::construct 77 void 78 construct(pointer __p, const _Tp& __val) 79 { ::new((void *)__p) value_type(__val); } 80 81 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 82 template<typename... _Args> 83 void 84 construct(pointer __p, _Args&&... __args) 85 { ::new((void *)__p) _Tp(std::forward<_Args>(__args)...); } 86 #endif 87 88 void 89 destroy(pointer __p) { __p->~_Tp(); } 90 }; 91 92 /** 93 * @brief An allocator that uses previously allocated memory. 94 * This memory can be externally, globally, or otherwise allocated. 95 * @ingroup allocators 96 */ 97 template<typename _Tp, typename _Array = std::tr1::array<_Tp, 1> > 98 class array_allocator : public array_allocator_base<_Tp> 99 { 100 public: 101 typedef size_t size_type; 102 typedef ptrdiff_t difference_type; 103 typedef _Tp* pointer; 104 typedef const _Tp* const_pointer; 105 typedef _Tp& reference; 106 typedef const _Tp& const_reference; 107 typedef _Tp value_type; 108 typedef _Array array_type; 109 110 private: 111 array_type* _M_array; 112 size_type _M_used; 113 114 public: 115 template<typename _Tp1, typename _Array1 = _Array> 116 struct rebind 117 { typedef array_allocator<_Tp1, _Array1> other; }; 118 119 array_allocator(array_type* __array = 0) throw() 120 : _M_array(__array), _M_used(size_type()) { } 121 122 array_allocator(const array_allocator& __o) throw() 123 : _M_array(__o._M_array), _M_used(__o._M_used) { } 124 125 template<typename _Tp1, typename _Array1> 126 array_allocator(const array_allocator<_Tp1, _Array1>&) throw() 127 : _M_array(0), _M_used(size_type()) { } 128 129 ~array_allocator() throw() { } 130 131 pointer 132 allocate(size_type __n, const void* = 0) 133 { 134 if (_M_array == 0 || _M_used + __n > _M_array->size()) 135 std::__throw_bad_alloc(); 136 pointer __ret = _M_array->begin() + _M_used; 137 _M_used += __n; 138 return __ret; 139 } 140 }; 141 142 template<typename _Tp, typename _Array> 143 inline bool 144 operator==(const array_allocator<_Tp, _Array>&, 145 const array_allocator<_Tp, _Array>&) 146 { return true; } 147 148 template<typename _Tp, typename _Array> 149 inline bool 150 operator!=(const array_allocator<_Tp, _Array>&, 151 const array_allocator<_Tp, _Array>&) 152 { return false; } 153 154 _GLIBCXX_END_NAMESPACE_VERSION 155 } // namespace 156 157 #endif 158
