new_allocator.h revision 132720
1// Allocator that wraps operator new -*- C++ -*- 2 3// Copyright (C) 2001, 2002, 2003, 2004 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, 59 Temple Place - Suite 330, Boston, MA 02111-1307, 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#ifndef _NEW_ALLOCATOR_H 31#define _NEW_ALLOCATOR_H 1 32 33#include <new> 34 35namespace __gnu_cxx 36{ 37 /** 38 * @brief An allocator that uses global new, as per [20.4]. 39 * 40 * This is precisely the allocator defined in the C++ Standard. 41 * - all allocation calls operator new 42 * - all deallocation calls operator delete 43 * 44 * (See @link Allocators allocators info @endlink for more.) 45 */ 46 template<typename _Tp> 47 class new_allocator 48 { 49 public: 50 typedef size_t size_type; 51 typedef ptrdiff_t difference_type; 52 typedef _Tp* pointer; 53 typedef const _Tp* const_pointer; 54 typedef _Tp& reference; 55 typedef const _Tp& const_reference; 56 typedef _Tp value_type; 57 58 template<typename _Tp1> 59 struct rebind 60 { typedef new_allocator<_Tp1> other; }; 61 62 new_allocator() throw() { } 63 64 new_allocator(const new_allocator&) throw() { } 65 66 template<typename _Tp1> 67 new_allocator(const new_allocator<_Tp1>&) throw() { } 68 69 ~new_allocator() throw() { } 70 71 pointer 72 address(reference __x) const { return &__x; } 73 74 const_pointer 75 address(const_reference __x) const { return &__x; } 76 77 // NB: __n is permitted to be 0. The C++ standard says nothing 78 // about what the return value is when __n == 0. 79 pointer 80 allocate(size_type __n, const void* = 0) 81 { return static_cast<_Tp*>(::operator new(__n * sizeof(_Tp))); } 82 83 // __p is not permitted to be a null pointer. 84 void 85 deallocate(pointer __p, size_type) 86 { ::operator delete(__p); } 87 88 size_type 89 max_size() const throw() 90 { return size_t(-1) / sizeof(_Tp); } 91 92 // _GLIBCXX_RESOLVE_LIB_DEFECTS 93 // 402. wrong new expression in [some_] allocator::construct 94 void 95 construct(pointer __p, const _Tp& __val) 96 { ::new(__p) _Tp(__val); } 97 98 void 99 destroy(pointer __p) { __p->~_Tp(); } 100 }; 101 102 template<typename _Tp> 103 inline bool 104 operator==(const new_allocator<_Tp>&, const new_allocator<_Tp>&) 105 { return true; } 106 107 template<typename _Tp> 108 inline bool 109 operator!=(const new_allocator<_Tp>&, const new_allocator<_Tp>&) 110 { return false; } 111} // namespace __gnu_cxx 112 113#endif 114