| // 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 |