1 // Allocator that wraps "C" malloc -*- C++ -*- 2 3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 4 // 2010, 2011 5 // Free Software Foundation, Inc. 6 // 7 // This file is part of the GNU ISO C++ Library. This library is free 8 // software; you can redistribute it and/or modify it under the 9 // terms of the GNU General Public License as published by the 10 // Free Software Foundation; either version 3, or (at your option) 11 // any later version. 12 13 // This library is distributed in the hope that it will be useful, 14 // but WITHOUT ANY WARRANTY; without even the implied warranty of 15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 // GNU General Public License for more details. 17 18 // Under Section 7 of GPL version 3, you are granted additional 19 // permissions described in the GCC Runtime Library Exception, version 20 // 3.1, as published by the Free Software Foundation. 21 22 // You should have received a copy of the GNU General Public License and 23 // a copy of the GCC Runtime Library Exception along with this program; 24 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 25 // <http://www.gnu.org/licenses/>. 26 27 /** @file ext/malloc_allocator.h 28 * This file is a GNU extension to the Standard C++ Library. 29 */ 30 31 #ifndef _MALLOC_ALLOCATOR_H 32 #define _MALLOC_ALLOCATOR_H 1 33 34 #include <cstdlib> 35 #include <new> 36 #include <bits/functexcept.h> 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 /** 47 * @brief An allocator that uses malloc. 48 * @ingroup allocators 49 * 50 * This is precisely the allocator defined in the C++ Standard. 51 * - all allocation calls malloc 52 * - all deallocation calls free 53 */ 54 template<typename _Tp> 55 class malloc_allocator 56 { 57 public: 58 typedef size_t size_type; 59 typedef ptrdiff_t difference_type; 60 typedef _Tp* pointer; 61 typedef const _Tp* const_pointer; 62 typedef _Tp& reference; 63 typedef const _Tp& const_reference; 64 typedef _Tp value_type; 65 66 template<typename _Tp1> 67 struct rebind 68 { typedef malloc_allocator<_Tp1> other; }; 69 70 malloc_allocator() _GLIBCXX_USE_NOEXCEPT { } 71 72 malloc_allocator(const malloc_allocator&) _GLIBCXX_USE_NOEXCEPT { } 73 74 template<typename _Tp1> 75 malloc_allocator(const malloc_allocator<_Tp1>&) 76 _GLIBCXX_USE_NOEXCEPT { } 77 78 ~malloc_allocator() _GLIBCXX_USE_NOEXCEPT { } 79 80 pointer 81 address(reference __x) const _GLIBCXX_NOEXCEPT 82 { return std::__addressof(__x); } 83 84 const_pointer 85 address(const_reference __x) const _GLIBCXX_NOEXCEPT 86 { return std::__addressof(__x); } 87 88 // NB: __n is permitted to be 0. The C++ standard says nothing 89 // about what the return value is when __n == 0. 90 pointer 91 allocate(size_type __n, const void* = 0) 92 { 93 if (__n > this->max_size()) 94 std::__throw_bad_alloc(); 95 96 pointer __ret = static_cast<_Tp*>(std::malloc(__n * sizeof(_Tp))); 97 if (!__ret) 98 std::__throw_bad_alloc(); 99 return __ret; 100 } 101 102 // __p is not permitted to be a null pointer. 103 void 104 deallocate(pointer __p, size_type) 105 { std::free(static_cast<void*>(__p)); } 106 107 size_type 108 max_size() const _GLIBCXX_USE_NOEXCEPT 109 { return size_t(-1) / sizeof(_Tp); } 110 111 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 112 template<typename _Up, typename... _Args> 113 void 114 construct(_Up* __p, _Args&&... __args) 115 { ::new((void *)__p) _Up(std::forward<_Args>(__args)...); } 116 117 template<typename _Up> 118 void 119 destroy(_Up* __p) { __p->~_Up(); } 120 #else 121 // _GLIBCXX_RESOLVE_LIB_DEFECTS 122 // 402. wrong new expression in [some_] allocator::construct 123 void 124 construct(pointer __p, const _Tp& __val) 125 { ::new((void *)__p) value_type(__val); } 126 127 void 128 destroy(pointer __p) { __p->~_Tp(); } 129 #endif 130 }; 131 132 template<typename _Tp> 133 inline bool 134 operator==(const malloc_allocator<_Tp>&, const malloc_allocator<_Tp>&) 135 { return true; } 136 137 template<typename _Tp> 138 inline bool 139 operator!=(const malloc_allocator<_Tp>&, const malloc_allocator<_Tp>&) 140 { return false; } 141 142 _GLIBCXX_END_NAMESPACE_VERSION 143 } // namespace 144 145 #endif 146