diff options
Diffstat (limited to 'gcc-4.4.3/libstdc++-v3/include/bits/stl_tempbuf.h')
| -rw-r--r-- | gcc-4.4.3/libstdc++-v3/include/bits/stl_tempbuf.h | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/gcc-4.4.3/libstdc++-v3/include/bits/stl_tempbuf.h b/gcc-4.4.3/libstdc++-v3/include/bits/stl_tempbuf.h new file mode 100644 index 000000000..a3b081007 --- /dev/null +++ b/gcc-4.4.3/libstdc++-v3/include/bits/stl_tempbuf.h @@ -0,0 +1,206 @@ +// Temporary buffer implementation -*- C++ -*- + +// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 +// 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 3, 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. + +// Under Section 7 of GPL version 3, you are granted additional +// permissions described in the GCC Runtime Library Exception, version +// 3.1, as published by the Free Software Foundation. + +// You should have received a copy of the GNU General Public License and +// a copy of the GCC Runtime Library Exception along with this program; +// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see +// <http://www.gnu.org/licenses/>. + +/* + * + * Copyright (c) 1994 + * Hewlett-Packard Company + * + * 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. Hewlett-Packard Company makes no + * representations about the suitability of this software for any + * purpose. It is provided "as is" without express or implied warranty. + * + * + * 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 stl_tempbuf.h + * This is an internal header file, included by other library headers. + * You should not attempt to use it directly. + */ + +#ifndef _STL_TEMPBUF_H +#define _STL_TEMPBUF_H 1 + +#include <bits/stl_algobase.h> +#include <bits/stl_construct.h> +#include <bits/stl_uninitialized.h> + +_GLIBCXX_BEGIN_NAMESPACE(std) + + /** + * @brief Allocates a temporary buffer. + * @param len The number of objects of type Tp. + * @return See full description. + * + * Reinventing the wheel, but this time with prettier spokes! + * + * This function tries to obtain storage for @c len adjacent Tp + * objects. The objects themselves are not constructed, of course. + * A pair<> is returned containing "the buffer s address and + * capacity (in the units of sizeof(Tp)), or a pair of 0 values if + * no storage can be obtained." Note that the capacity obtained + * may be less than that requested if the memory is unavailable; + * you should compare len with the .second return value. + * + * Provides the nothrow exception guarantee. + */ + template<typename _Tp> + pair<_Tp*, ptrdiff_t> + get_temporary_buffer(ptrdiff_t __len) + { + const ptrdiff_t __max = + __gnu_cxx::__numeric_traits<ptrdiff_t>::__max / sizeof(_Tp); + if (__len > __max) + __len = __max; + + while (__len > 0) + { + _Tp* __tmp = static_cast<_Tp*>(::operator new(__len * sizeof(_Tp), + std::nothrow)); + if (__tmp != 0) + return std::pair<_Tp*, ptrdiff_t>(__tmp, __len); + __len /= 2; + } + return std::pair<_Tp*, ptrdiff_t>(static_cast<_Tp*>(0), 0); + } + + /** + * @brief The companion to get_temporary_buffer(). + * @param p A buffer previously allocated by get_temporary_buffer. + * @return None. + * + * Frees the memory pointed to by p. + */ + template<typename _Tp> + inline void + return_temporary_buffer(_Tp* __p) + { ::operator delete(__p, std::nothrow); } + + + /** + * This class is used in two places: stl_algo.h and ext/memory, + * where it is wrapped as the temporary_buffer class. See + * temporary_buffer docs for more notes. + */ + template<typename _ForwardIterator, typename _Tp> + class _Temporary_buffer + { + // concept requirements + __glibcxx_class_requires(_ForwardIterator, _ForwardIteratorConcept) + + public: + typedef _Tp value_type; + typedef value_type* pointer; + typedef pointer iterator; + typedef ptrdiff_t size_type; + + protected: + size_type _M_original_len; + size_type _M_len; + pointer _M_buffer; + + public: + /// As per Table mumble. + size_type + size() const + { return _M_len; } + + /// Returns the size requested by the constructor; may be >size(). + size_type + requested_size() const + { return _M_original_len; } + + /// As per Table mumble. + iterator + begin() + { return _M_buffer; } + + /// As per Table mumble. + iterator + end() + { return _M_buffer + _M_len; } + + /** + * Constructs a temporary buffer of a size somewhere between + * zero and the size of the given range. + */ + _Temporary_buffer(_ForwardIterator __first, _ForwardIterator __last); + + ~_Temporary_buffer() + { + std::_Destroy(_M_buffer, _M_buffer + _M_len); + std::return_temporary_buffer(_M_buffer); + } + + private: + // Disable copy constructor and assignment operator. + _Temporary_buffer(const _Temporary_buffer&); + + void + operator=(const _Temporary_buffer&); + }; + + template<typename _ForwardIterator, typename _Tp> + _Temporary_buffer<_ForwardIterator, _Tp>:: + _Temporary_buffer(_ForwardIterator __first, _ForwardIterator __last) + : _M_original_len(std::distance(__first, __last)), + _M_len(0), _M_buffer(0) + { + __try + { + std::pair<pointer, size_type> __p(std::get_temporary_buffer< + value_type>(_M_original_len)); + _M_buffer = __p.first; + _M_len = __p.second; + if (!__is_pod(_Tp) && _M_len > 0) + std::uninitialized_fill_n(_M_buffer, _M_len, *__first); + } + __catch(...) + { + std::return_temporary_buffer(_M_buffer); + _M_buffer = 0; + _M_len = 0; + __throw_exception_again; + } + } + +_GLIBCXX_END_NAMESPACE + +#endif /* _STL_TEMPBUF_H */ + |