1 // Allocator that wraps operator new -*- C++ -*- 2 3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2009 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/new_allocator.h 27 * This file is a GNU extension to the Standard C++ Library. 28 */ 29 30 #ifndef _NEW_ALLOCATOR_H 31 #define _NEW_ALLOCATOR_H 1 32 33 #include <new> 34 #include <bits/functexcept.h> 35 #include <bits/move.h> 36 37 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx) 38 39 using std::size_t; 40 using std::ptrdiff_t; 41 42 /** 43 * @brief An allocator that uses global new, as per [20.4]. 44 * @ingroup allocators 45 * 46 * This is precisely the allocator defined in the C++ Standard. 47 * - all allocation calls operator new 48 * - all deallocation calls operator delete 49 */ 50 template<typename _Tp> 51 class new_allocator 52 { 53 public: 54 typedef size_t size_type; 55 typedef ptrdiff_t difference_type; 56 typedef _Tp* pointer; 57 typedef const _Tp* const_pointer; 58 typedef _Tp& reference; 59 typedef const _Tp& const_reference; 60 typedef _Tp value_type; 61 62 template<typename _Tp1> 63 struct rebind 64 { typedef new_allocator<_Tp1> other; }; 65 66 new_allocator() throw() { } 67 68 new_allocator(const new_allocator&) throw() { } 69 70 template<typename _Tp1> 71 new_allocator(const new_allocator<_Tp1>&) throw() { } 72 73 ~new_allocator() throw() { } 74 75 pointer 76 address(reference __x) const { return &__x; } 77 78 const_pointer 79 address(const_reference __x) const { return &__x; } 80 81 // NB: __n is permitted to be 0. The C++ standard says nothing 82 // about what the return value is when __n == 0. 83 pointer 84 allocate(size_type __n, const void* = 0) 85 { 86 if (__builtin_expect(__n > this->max_size(), false)) 87 std::__throw_bad_alloc(); 88 89 return static_cast<_Tp*>(::operator new(__n * sizeof(_Tp))); 90 } 91 92 // __p is not permitted to be a null pointer. 93 void 94 deallocate(pointer __p, size_type) 95 { ::operator delete(__p); } 96 97 size_type 98 max_size() const throw() 99 { return size_t(-1) / sizeof(_Tp); } 100 101 // _GLIBCXX_RESOLVE_LIB_DEFECTS 102 // 402. wrong new expression in [some_] allocator::construct 103 void 104 construct(pointer __p, const _Tp& __val) 105 { ::new((void *)__p) _Tp(__val); } 106 107 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 108 template<typename... _Args> 109 void 110 construct(pointer __p, _Args&&... __args) 111 { ::new((void *)__p) _Tp(std::forward<_Args>(__args)...); } 112 #endif 113 114 void 115 destroy(pointer __p) { __p->~_Tp(); } 116 }; 117 118 template<typename _Tp> 119 inline bool 120 operator==(const new_allocator<_Tp>&, const new_allocator<_Tp>&) 121 { return true; } 122 123 template<typename _Tp> 124 inline bool 125 operator!=(const new_allocator<_Tp>&, const new_allocator<_Tp>&) 126 { return false; } 127 128 _GLIBCXX_END_NAMESPACE 129 130 #endif 131
