1*404b540aSrobert // Allocators -*- C++ -*- 2*404b540aSrobert 3*404b540aSrobert // Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc. 4*404b540aSrobert // 5*404b540aSrobert // This file is part of the GNU ISO C++ Library. This library is free 6*404b540aSrobert // software; you can redistribute it and/or modify it under the 7*404b540aSrobert // terms of the GNU General Public License as published by the 8*404b540aSrobert // Free Software Foundation; either version 2, or (at your option) 9*404b540aSrobert // any later version. 10*404b540aSrobert 11*404b540aSrobert // This library is distributed in the hope that it will be useful, 12*404b540aSrobert // but WITHOUT ANY WARRANTY; without even the implied warranty of 13*404b540aSrobert // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14*404b540aSrobert // GNU General Public License for more details. 15*404b540aSrobert 16*404b540aSrobert // You should have received a copy of the GNU General Public License along 17*404b540aSrobert // with this library; see the file COPYING. If not, write to the Free 18*404b540aSrobert // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 19*404b540aSrobert // USA. 20*404b540aSrobert 21*404b540aSrobert // As a special exception, you may use this file as part of a free software 22*404b540aSrobert // library without restriction. Specifically, if other files instantiate 23*404b540aSrobert // templates or use macros or inline functions from this file, or you compile 24*404b540aSrobert // this file and link it with other files to produce an executable, this 25*404b540aSrobert // file does not by itself cause the resulting executable to be covered by 26*404b540aSrobert // the GNU General Public License. This exception does not however 27*404b540aSrobert // invalidate any other reasons why the executable file might be covered by 28*404b540aSrobert // the GNU General Public License. 29*404b540aSrobert 30*404b540aSrobert /* 31*404b540aSrobert * Copyright (c) 1996-1997 32*404b540aSrobert * Silicon Graphics Computer Systems, Inc. 33*404b540aSrobert * 34*404b540aSrobert * Permission to use, copy, modify, distribute and sell this software 35*404b540aSrobert * and its documentation for any purpose is hereby granted without fee, 36*404b540aSrobert * provided that the above copyright notice appear in all copies and 37*404b540aSrobert * that both that copyright notice and this permission notice appear 38*404b540aSrobert * in supporting documentation. Silicon Graphics makes no 39*404b540aSrobert * representations about the suitability of this software for any 40*404b540aSrobert * purpose. It is provided "as is" without express or implied warranty. 41*404b540aSrobert */ 42*404b540aSrobert 43*404b540aSrobert /** @file ext/debug_allocator.h 44*404b540aSrobert * This file is a GNU extension to the Standard C++ Library. 45*404b540aSrobert * You should only include this header if you are using GCC 3 or later. 46*404b540aSrobert */ 47*404b540aSrobert 48*404b540aSrobert #ifndef _DEBUG_ALLOCATOR_H 49*404b540aSrobert #define _DEBUG_ALLOCATOR_H 1 50*404b540aSrobert 51*404b540aSrobert #include <stdexcept> 52*404b540aSrobert 53*404b540aSrobert _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx) 54*404b540aSrobert 55*404b540aSrobert using std::size_t; 56*404b540aSrobert 57*404b540aSrobert /** 58*404b540aSrobert * @brief A meta-allocator with debugging bits, as per [20.4]. 59*404b540aSrobert * 60*404b540aSrobert * This is precisely the allocator defined in the C++ Standard. 61*404b540aSrobert * - all allocation calls operator new 62*404b540aSrobert * - all deallocation calls operator delete 63*404b540aSrobert */ 64*404b540aSrobert template<typename _Alloc> 65*404b540aSrobert class debug_allocator 66*404b540aSrobert { 67*404b540aSrobert public: 68*404b540aSrobert typedef typename _Alloc::size_type size_type; 69*404b540aSrobert typedef typename _Alloc::difference_type difference_type; 70*404b540aSrobert typedef typename _Alloc::pointer pointer; 71*404b540aSrobert typedef typename _Alloc::const_pointer const_pointer; 72*404b540aSrobert typedef typename _Alloc::reference reference; 73*404b540aSrobert typedef typename _Alloc::const_reference const_reference; 74*404b540aSrobert typedef typename _Alloc::value_type value_type; 75*404b540aSrobert 76*404b540aSrobert private: 77*404b540aSrobert // _M_extra is the number of objects that correspond to the 78*404b540aSrobert // extra space where debug information is stored. 79*404b540aSrobert size_type _M_extra; 80*404b540aSrobert 81*404b540aSrobert _Alloc _M_allocator; 82*404b540aSrobert 83*404b540aSrobert public: debug_allocator()84*404b540aSrobert debug_allocator() 85*404b540aSrobert { 86*404b540aSrobert const size_t __obj_size = sizeof(value_type); 87*404b540aSrobert _M_extra = (sizeof(size_type) + __obj_size - 1) / __obj_size; 88*404b540aSrobert } 89*404b540aSrobert 90*404b540aSrobert pointer allocate(size_type __n)91*404b540aSrobert allocate(size_type __n) 92*404b540aSrobert { 93*404b540aSrobert pointer __res = _M_allocator.allocate(__n + _M_extra); 94*404b540aSrobert size_type* __ps = reinterpret_cast<size_type*>(__res); 95*404b540aSrobert *__ps = __n; 96*404b540aSrobert return __res + _M_extra; 97*404b540aSrobert } 98*404b540aSrobert 99*404b540aSrobert pointer allocate(size_type __n,const void * __hint)100*404b540aSrobert allocate(size_type __n, const void* __hint) 101*404b540aSrobert { 102*404b540aSrobert pointer __res = _M_allocator.allocate(__n + _M_extra, __hint); 103*404b540aSrobert size_type* __ps = reinterpret_cast<size_type*>(__res); 104*404b540aSrobert *__ps = __n; 105*404b540aSrobert return __res + _M_extra; 106*404b540aSrobert } 107*404b540aSrobert 108*404b540aSrobert void deallocate(pointer __p,size_type __n)109*404b540aSrobert deallocate(pointer __p, size_type __n) 110*404b540aSrobert { 111*404b540aSrobert if (__p) 112*404b540aSrobert { 113*404b540aSrobert pointer __real_p = __p - _M_extra; 114*404b540aSrobert if (*reinterpret_cast<size_type*>(__real_p) != __n) 115*404b540aSrobert { 116*404b540aSrobert throw std::runtime_error("debug_allocator::deallocate" 117*404b540aSrobert " wrong size"); 118*404b540aSrobert } 119*404b540aSrobert _M_allocator.deallocate(__real_p, __n + _M_extra); 120*404b540aSrobert } 121*404b540aSrobert else 122*404b540aSrobert throw std::runtime_error("debug_allocator::deallocate null pointer"); 123*404b540aSrobert } 124*404b540aSrobert }; 125*404b540aSrobert 126*404b540aSrobert _GLIBCXX_END_NAMESPACE 127*404b540aSrobert 128*404b540aSrobert #endif 129