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 
64 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
65 {
66 _GLIBCXX_BEGIN_NAMESPACE_VERSION
67 
69 
70  template<typename _InputIter, typename _Size, typename _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>
91  __uninitialized_copy_n(_RandomAccessIter __first, _Size __count,
92  _ForwardIter __result,
94  {
95  _RandomAccessIter __last = __first + __count;
97  (__last, std::uninitialized_copy(__first, __last, __result)));
98  }
99 
100  template<typename _InputIter, typename _Size, typename _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>
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>
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>
155  __uninitialized_copy_n_a(_InputIter __first, _Size __count,
156  _ForwardIter __result,
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
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.
194  };
195 
196 _GLIBCXX_END_NAMESPACE_VERSION
197 } // namespace
198 
199 #endif
200 
std::pair< _InputIter, _ForwardIter > uninitialized_copy_n(_InputIter __first, _Size __count, _ForwardIter __result)
Copies the range [first,last) into result.
Definition: ext/memory:121
void distance(_InputIterator __first, _InputIterator __last, _Distance &__n)
Definition: ext/iterator:105
_ForwardIterator uninitialized_copy(_InputIterator __first, _InputIterator __last, _ForwardIterator __result)
Copies the range [first,last) into result.
constexpr iterator_traits< _Iter >::iterator_category __iterator_category(const _Iter &)
ISO C++ entities toplevel namespace is std.
void _Construct(_Tp *__p, _Args &&... __args)
void _Destroy(_ForwardIterator __first, _ForwardIterator __last, _Allocator &__alloc)
GNU extensions for public use.
The standard allocator, as per C++03 [20.4.1].
Definition: allocator.h:141
Traits class for iterators.
Marking input iterators.
Random-access iterators support a superset of bidirectional iterator operations.
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:202
temporary_buffer(_ForwardIterator __first, _ForwardIterator __last)
Requests storage large enough to hold a copy of [first,last).
Definition: ext/memory:187
~temporary_buffer()
Destroys objects and frees storage.
Definition: ext/memory:193