--- /dev/null
+// 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 */
+
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