// Allocators -*- C++ -*- // Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc. // // This file is part of the GNU ISO C++ Library. This library is free // software; you can redistribute it and/or modify it under the // terms of the GNU General Public License as published by the // Free Software Foundation; either version 2, or (at your option) // any later version. // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // You should have received a copy of the GNU General Public License along // with this library; see the file COPYING. If not, write to the Free // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, // USA. // As a special exception, you may use this file as part of a free software // library without restriction. Specifically, if other files instantiate // templates or use macros or inline functions from this file, or you compile // this file and link it with other files to produce an executable, this // file does not by itself cause the resulting executable to be covered by // the GNU General Public License. This exception does not however // invalidate any other reasons why the executable file might be covered by // the GNU General Public License. /* * Copyright (c) 1996-1997 * Silicon Graphics Computer Systems, Inc. * * Permission to use, copy, modify, distribute and sell this software * and its documentation for any purpose is hereby granted without fee, * provided that the above copyright notice appear in all copies and * that both that copyright notice and this permission notice appear * in supporting documentation. Silicon Graphics makes no * representations about the suitability of this software for any * purpose. It is provided "as is" without express or implied warranty. */ /** @file ext/debug_allocator.h * This file is a GNU extension to the Standard C++ Library. * You should only include this header if you are using GCC 3 or later. */ #ifndef _DEBUG_ALLOCATOR_H #define _DEBUG_ALLOCATOR_H 1 #include <stdexcept> _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx) using std::size_t; /** * @brief A meta-allocator with debugging bits, as per [20.4]. * * This is precisely the allocator defined in the C++ Standard. * - all allocation calls operator new * - all deallocation calls operator delete */ template<typename _Alloc> class debug_allocator { public: typedef typename _Alloc::size_type size_type; typedef typename _Alloc::difference_type difference_type; typedef typename _Alloc::pointer pointer; typedef typename _Alloc::const_pointer const_pointer; typedef typename _Alloc::reference reference; typedef typename _Alloc::const_reference const_reference; typedef typename _Alloc::value_type value_type; private: // _M_extra is the number of objects that correspond to the // extra space where debug information is stored. size_type _M_extra; _Alloc _M_allocator; public: debug_allocator() { const size_t __obj_size = sizeof(value_type); _M_extra = (sizeof(size_type) + __obj_size - 1) / __obj_size; } pointer allocate(size_type __n) { pointer __res = _M_allocator.allocate(__n + _M_extra); size_type* __ps = reinterpret_cast<size_type*>(__res); *__ps = __n; return __res + _M_extra; } pointer allocate(size_type __n, const void* __hint) { pointer __res = _M_allocator.allocate(__n + _M_extra, __hint); size_type* __ps = reinterpret_cast<size_type*>(__res); *__ps = __n; return __res + _M_extra; } void deallocate(pointer __p, size_type __n) { if (__p) { pointer __real_p = __p - _M_extra; if (*reinterpret_cast<size_type*>(__real_p) != __n) { throw std::runtime_error("debug_allocator::deallocate" " wrong size"); } _M_allocator.deallocate(__real_p, __n + _M_extra); } else throw std::runtime_error("debug_allocator::deallocate null pointer"); } }; _GLIBCXX_END_NAMESPACE #endif