1 // Allocator that wraps "C" malloc -*- C++ -*- 2 3 // Copyright (C) 2001, 2002, 2003, 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/malloc_allocator.h 27 * This file is a GNU extension to the Standard C++ Library. 28 */ 29 30 #ifndef _MALLOC_ALLOCATOR_H 31 #define _MALLOC_ALLOCATOR_H 1 32 33 #include <cstdlib> 34 #include <new> 35 #include <bits/functexcept.h> 36 #include <bits/move.h> 37 38 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) 39 { 40 _GLIBCXX_BEGIN_NAMESPACE_VERSION 41 42 using std::size_t; 43 using std::ptrdiff_t; 44 45 /** 46 * @brief An allocator that uses malloc. 47 * @ingroup allocators 48 * 49 * This is precisely the allocator defined in the C++ Standard. 50 * - all allocation calls malloc 51 * - all deallocation calls free 52 */ 53 template<typename _Tp> 54 class malloc_allocator 55 { 56 public: 57 typedef size_t size_type; 58 typedef ptrdiff_t difference_type; 59 typedef _Tp* pointer; 60 typedef const _Tp* const_pointer; 61 typedef _Tp& reference; 62 typedef const _Tp& const_reference; 63 typedef _Tp value_type; 64 65 template<typename _Tp1> 66 struct rebind 67 { typedef malloc_allocator<_Tp1> other; }; 68 69 malloc_allocator() throw() { } 70 71 malloc_allocator(const malloc_allocator&) throw() { } 72 73 template<typename _Tp1> 74 malloc_allocator(const malloc_allocator<_Tp1>&) throw() { } 75 76 ~malloc_allocator() throw() { } 77 78 pointer 79 address(reference __x) const { return std::__addressof(__x); } 80 81 const_pointer 82 address(const_reference __x) const { return std::__addressof(__x); } 83 84 // NB: __n is permitted to be 0. The C++ standard says nothing 85 // about what the return value is when __n == 0. 86 pointer 87 allocate(size_type __n, const void* = 0) 88 { 89 if (__n > this->max_size()) 90 std::__throw_bad_alloc(); 91 92 pointer __ret = static_cast<_Tp*>(std::malloc(__n * sizeof(_Tp))); 93 if (!__ret) 94 std::__throw_bad_alloc(); 95 return __ret; 96 } 97 98 // __p is not permitted to be a null pointer. 99 void 100 deallocate(pointer __p, size_type) 101 { std::free(static_cast<void*>(__p)); } 102 103 size_type 104 max_size() const throw() 105 { return size_t(-1) / sizeof(_Tp); } 106 107 // _GLIBCXX_RESOLVE_LIB_DEFECTS 108 // 402. wrong new expression in [some_] allocator::construct 109 void 110 construct(pointer __p, const _Tp& __val) 111 { ::new((void *)__p) value_type(__val); } 112 113 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 114 template<typename... _Args> 115 void 116 construct(pointer __p, _Args&&... __args) 117 { ::new((void *)__p) _Tp(std::forward<_Args>(__args)...); } 118 #endif 119 120 void 121 destroy(pointer __p) { __p->~_Tp(); } 122 }; 123 124 template<typename _Tp> 125 inline bool 126 operator==(const malloc_allocator<_Tp>&, const malloc_allocator<_Tp>&) 127 { return true; } 128 129 template<typename _Tp> 130 inline bool 131 operator!=(const malloc_allocator<_Tp>&, const malloc_allocator<_Tp>&) 132 { return false; } 133 134 _GLIBCXX_END_NAMESPACE_VERSION 135 } // namespace 136 137 #endif 138