1 // Allocator that wraps "C" malloc -*- C++ -*- 2 3 // Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the 7 // terms of the GNU General Public License as published by the 8 // Free Software Foundation; either version 2, or (at your option) 9 // any later version. 10 11 // This library is distributed in the hope that it will be useful, 12 // but WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 // GNU General Public License for more details. 15 16 // You should have received a copy of the GNU General Public License along 17 // with this library; see the file COPYING. If not, write to the Free 18 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 19 // USA. 20 21 // As a special exception, you may use this file as part of a free software 22 // library without restriction. Specifically, if other files instantiate 23 // templates or use macros or inline functions from this file, or you compile 24 // this file and link it with other files to produce an executable, this 25 // file does not by itself cause the resulting executable to be covered by 26 // the GNU General Public License. This exception does not however 27 // invalidate any other reasons why the executable file might be covered by 28 // the GNU General Public License. 29 30 /** @file ext/malloc_allocator.h 31 * This file is a GNU extension to the Standard C++ Library. 32 */ 33 34 #ifndef _MALLOC_ALLOCATOR_H 35 #define _MALLOC_ALLOCATOR_H 1 36 37 #include <cstdlib> 38 #include <new> 39 #include <bits/functexcept.h> 40 41 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx) 42 43 using std::size_t; 44 using std::ptrdiff_t; 45 46 /** 47 * @brief An allocator that uses malloc. 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 &__x; } 80 81 const_pointer 82 address(const_reference __x) const { return &__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 (__builtin_expect(__n > this->max_size(), false)) 90 std::__throw_bad_alloc(); 91 92 pointer __ret = static_cast<_Tp*>(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 { 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(__p) value_type(__val); } 112 113 void 114 destroy(pointer __p) { __p->~_Tp(); } 115 }; 116 117 template<typename _Tp> 118 inline bool 119 operator==(const malloc_allocator<_Tp>&, const malloc_allocator<_Tp>&) 120 { return true; } 121 122 template<typename _Tp> 123 inline bool 124 operator!=(const malloc_allocator<_Tp>&, const malloc_allocator<_Tp>&) 125 { return false; } 126 127 _GLIBCXX_END_NAMESPACE 128 129 #endif 130