libstdc++
ext/memory
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1// Memory extensions -*- C++ -*-
2
3// Copyright (C) 2002-2021 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/*
26 *
27 * Copyright (c) 1994
28 * Hewlett-Packard Company
29 *
30 * Permission to use, copy, modify, distribute and sell this software
31 * and its documentation for any purpose is hereby granted without fee,
32 * provided that the above copyright notice appear in all copies and
33 * that both that copyright notice and this permission notice appear
34 * in supporting documentation. Hewlett-Packard Company makes no
35 * representations about the suitability of this software for any
36 * purpose. It is provided "as is" without express or implied warranty.
37 *
38 *
39 * Copyright (c) 1996
40 * Silicon Graphics Computer Systems, Inc.
41 *
42 * Permission to use, copy, modify, distribute and sell this software
43 * and its documentation for any purpose is hereby granted without fee,
44 * provided that the above copyright notice appear in all copies and
45 * that both that copyright notice and this permission notice appear
46 * in supporting documentation. Silicon Graphics makes no
47 * representations about the suitability of this software for any
48 * purpose. It is provided "as is" without express or implied warranty.
49 */
50
51/** @file ext/memory
52 * This file is a GNU extension to the Standard C++ Library (possibly
53 * containing extensions from the HP/SGI STL subset).
54 */
55
56#ifndef _EXT_MEMORY
57#define _EXT_MEMORY 1
58
59#pragma GCC system_header
60
61#include <memory>
62#include <bits/stl_tempbuf.h>
63
64namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
65{
66_GLIBCXX_BEGIN_NAMESPACE_VERSION
67
68 using std::_Temporary_buffer;
69
70 template<typename _InputIter, typename _Size, typename _ForwardIter>
71 std::pair<_InputIter, _ForwardIter>
72 __uninitialized_copy_n(_InputIter __first, _Size __count,
73 _ForwardIter __result, std::input_iterator_tag)
74 {
75 _ForwardIter __cur = __result;
76 __try
77 {
78 for (; __count > 0 ; --__count, ++__first, ++__cur)
79 std::_Construct(&*__cur, *__first);
80 return std::pair<_InputIter, _ForwardIter>(__first, __cur);
81 }
82 __catch(...)
83 {
84 std::_Destroy(__result, __cur);
85 __throw_exception_again;
86 }
87 }
88
89 template<typename _RandomAccessIter, typename _Size, typename _ForwardIter>
90 inline std::pair<_RandomAccessIter, _ForwardIter>
91 __uninitialized_copy_n(_RandomAccessIter __first, _Size __count,
92 _ForwardIter __result,
93 std::random_access_iterator_tag)
94 {
95 _RandomAccessIter __last = __first + __count;
96 return (std::pair<_RandomAccessIter, _ForwardIter>
97 (__last, std::uninitialized_copy(__first, __last, __result)));
98 }
99
100 template<typename _InputIter, typename _Size, typename _ForwardIter>
101 inline std::pair<_InputIter, _ForwardIter>
102 __uninitialized_copy_n(_InputIter __first, _Size __count,
103 _ForwardIter __result)
104 {
105 return __gnu_cxx::__uninitialized_copy_n(__first, __count, __result,
106 std::__iterator_category(__first));
107 }
108
109 /**
110 * @brief Copies the range [first,last) into result.
111 * @param __first An input iterator.
112 * @param __count Length
113 * @param __result An output iterator.
114 * @return __result + (__first + __count)
115 * @ingroup SGIextensions
116 *
117 * Like copy(), but does not require an initialized output range.
118 */
119 template<typename _InputIter, typename _Size, typename _ForwardIter>
120 inline std::pair<_InputIter, _ForwardIter>
121 uninitialized_copy_n(_InputIter __first, _Size __count,
122 _ForwardIter __result)
123 {
124 return __gnu_cxx::__uninitialized_copy_n(__first, __count, __result,
125 std::__iterator_category(__first));
126 }
127
128
129 // An alternative version of uninitialized_copy_n that constructs
130 // and destroys objects with a user-provided allocator.
131 template<typename _InputIter, typename _Size, typename _ForwardIter,
132 typename _Allocator>
133 std::pair<_InputIter, _ForwardIter>
134 __uninitialized_copy_n_a(_InputIter __first, _Size __count,
135 _ForwardIter __result,
136 _Allocator __alloc)
137 {
138 _ForwardIter __cur = __result;
139 __try
140 {
141 for (; __count > 0 ; --__count, ++__first, ++__cur)
142 __alloc.construct(&*__cur, *__first);
143 return std::pair<_InputIter, _ForwardIter>(__first, __cur);
144 }
145 __catch(...)
146 {
147 std::_Destroy(__result, __cur, __alloc);
148 __throw_exception_again;
149 }
150 }
151
152 template<typename _InputIter, typename _Size, typename _ForwardIter,
153 typename _Tp>
154 inline std::pair<_InputIter, _ForwardIter>
155 __uninitialized_copy_n_a(_InputIter __first, _Size __count,
156 _ForwardIter __result,
157 std::allocator<_Tp>)
158 {
159 return __gnu_cxx::uninitialized_copy_n(__first, __count, __result);
160 }
161
162 /**
163 * This class provides similar behavior and semantics of the standard
164 * functions get_temporary_buffer() and return_temporary_buffer(), but
165 * encapsulated in a type vaguely resembling a standard container.
166 *
167 * By default, a temporary_buffer<Iter> stores space for objects of
168 * whatever type the Iter iterator points to. It is constructed from a
169 * typical [first,last) range, and provides the begin(), end(), size()
170 * functions, as well as requested_size(). For non-trivial types, copies
171 * of *first will be used to initialize the storage.
172 *
173 * @c malloc is used to obtain underlying storage.
174 *
175 * Like get_temporary_buffer(), not all the requested memory may be
176 * available. Ideally, the created buffer will be large enough to hold a
177 * copy of [first,last), but if size() is less than requested_size(),
178 * then this didn't happen.
179 *
180 * @ingroup SGIextensions
181 */
182 template <class _ForwardIterator, class _Tp
183 = typename std::iterator_traits<_ForwardIterator>::value_type >
184 struct temporary_buffer : public _Temporary_buffer<_ForwardIterator, _Tp>
185 {
186 /// Requests storage large enough to hold a copy of [first,last).
187 temporary_buffer(_ForwardIterator __first, _ForwardIterator __last)
188 : _Temporary_buffer<_ForwardIterator, _Tp>(__first,
189 std::distance(__first, __last))
190 { }
191
192 /// Destroys objects and frees storage.
193 ~temporary_buffer() { }
194 };
195
196_GLIBCXX_END_NAMESPACE_VERSION
197} // namespace
198
199#endif
200