libstdc++
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00001 // Allocator that wraps "C" malloc -*- C++ -*- 00002 00003 // Copyright (C) 2001-2013 Free Software Foundation, Inc. 00004 // 00005 // This file is part of the GNU ISO C++ Library. This library is free 00006 // software; you can redistribute it and/or modify it under the 00007 // terms of the GNU General Public License as published by the 00008 // Free Software Foundation; either version 3, or (at your option) 00009 // any later version. 00010 00011 // This library is distributed in the hope that it will be useful, 00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of 00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00014 // GNU General Public License for more details. 00015 00016 // Under Section 7 of GPL version 3, you are granted additional 00017 // permissions described in the GCC Runtime Library Exception, version 00018 // 3.1, as published by the Free Software Foundation. 00019 00020 // You should have received a copy of the GNU General Public License and 00021 // a copy of the GCC Runtime Library Exception along with this program; 00022 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 00023 // <http://www.gnu.org/licenses/>. 00024 00025 /** @file ext/malloc_allocator.h 00026 * This file is a GNU extension to the Standard C++ Library. 00027 */ 00028 00029 #ifndef _MALLOC_ALLOCATOR_H 00030 #define _MALLOC_ALLOCATOR_H 1 00031 00032 #include <cstdlib> 00033 #include <new> 00034 #include <bits/functexcept.h> 00035 #include <bits/move.h> 00036 #if __cplusplus >= 201103L 00037 #include <type_traits> 00038 #endif 00039 00040 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) 00041 { 00042 _GLIBCXX_BEGIN_NAMESPACE_VERSION 00043 00044 using std::size_t; 00045 using std::ptrdiff_t; 00046 00047 /** 00048 * @brief An allocator that uses malloc. 00049 * @ingroup allocators 00050 * 00051 * This is precisely the allocator defined in the C++ Standard. 00052 * - all allocation calls malloc 00053 * - all deallocation calls free 00054 */ 00055 template<typename _Tp> 00056 class malloc_allocator 00057 { 00058 public: 00059 typedef size_t size_type; 00060 typedef ptrdiff_t difference_type; 00061 typedef _Tp* pointer; 00062 typedef const _Tp* const_pointer; 00063 typedef _Tp& reference; 00064 typedef const _Tp& const_reference; 00065 typedef _Tp value_type; 00066 00067 template<typename _Tp1> 00068 struct rebind 00069 { typedef malloc_allocator<_Tp1> other; }; 00070 00071 #if __cplusplus >= 201103L 00072 // _GLIBCXX_RESOLVE_LIB_DEFECTS 00073 // 2103. propagate_on_container_move_assignment 00074 typedef std::true_type propagate_on_container_move_assignment; 00075 #endif 00076 00077 malloc_allocator() _GLIBCXX_USE_NOEXCEPT { } 00078 00079 malloc_allocator(const malloc_allocator&) _GLIBCXX_USE_NOEXCEPT { } 00080 00081 template<typename _Tp1> 00082 malloc_allocator(const malloc_allocator<_Tp1>&) 00083 _GLIBCXX_USE_NOEXCEPT { } 00084 00085 ~malloc_allocator() _GLIBCXX_USE_NOEXCEPT { } 00086 00087 pointer 00088 address(reference __x) const _GLIBCXX_NOEXCEPT 00089 { return std::__addressof(__x); } 00090 00091 const_pointer 00092 address(const_reference __x) const _GLIBCXX_NOEXCEPT 00093 { return std::__addressof(__x); } 00094 00095 // NB: __n is permitted to be 0. The C++ standard says nothing 00096 // about what the return value is when __n == 0. 00097 pointer 00098 allocate(size_type __n, const void* = 0) 00099 { 00100 if (__n > this->max_size()) 00101 std::__throw_bad_alloc(); 00102 00103 pointer __ret = static_cast<_Tp*>(std::malloc(__n * sizeof(_Tp))); 00104 if (!__ret) 00105 std::__throw_bad_alloc(); 00106 return __ret; 00107 } 00108 00109 // __p is not permitted to be a null pointer. 00110 void 00111 deallocate(pointer __p, size_type) 00112 { std::free(static_cast<void*>(__p)); } 00113 00114 size_type 00115 max_size() const _GLIBCXX_USE_NOEXCEPT 00116 { return size_t(-1) / sizeof(_Tp); } 00117 00118 #if __cplusplus >= 201103L 00119 template<typename _Up, typename... _Args> 00120 void 00121 construct(_Up* __p, _Args&&... __args) 00122 { ::new((void *)__p) _Up(std::forward<_Args>(__args)...); } 00123 00124 template<typename _Up> 00125 void 00126 destroy(_Up* __p) { __p->~_Up(); } 00127 #else 00128 // _GLIBCXX_RESOLVE_LIB_DEFECTS 00129 // 402. wrong new expression in [some_] allocator::construct 00130 void 00131 construct(pointer __p, const _Tp& __val) 00132 { ::new((void *)__p) value_type(__val); } 00133 00134 void 00135 destroy(pointer __p) { __p->~_Tp(); } 00136 #endif 00137 }; 00138 00139 template<typename _Tp> 00140 inline bool 00141 operator==(const malloc_allocator<_Tp>&, const malloc_allocator<_Tp>&) 00142 { return true; } 00143 00144 template<typename _Tp> 00145 inline bool 00146 operator!=(const malloc_allocator<_Tp>&, const malloc_allocator<_Tp>&) 00147 { return false; } 00148 00149 _GLIBCXX_END_NAMESPACE_VERSION 00150 } // namespace 00151 00152 #endif