libstdc++
safe_unordered_container.h
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1 // Safe container implementation -*- C++ -*-
2 
3 // Copyright (C) 2011-2017 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 /** @file debug/safe_unordered_container.h
26  * This file is a GNU debug extension to the Standard C++ Library.
27  */
28 
29 #ifndef _GLIBCXX_DEBUG_SAFE_UNORDERED_CONTAINER_H
30 #define _GLIBCXX_DEBUG_SAFE_UNORDERED_CONTAINER_H 1
31 
32 #include <debug/assertions.h>
33 #include <debug/macros.h>
34 #include <debug/functions.h>
36 
37 namespace __gnu_debug
38 {
39  /**
40  * @brief Base class for constructing a @a safe unordered container type
41  * that tracks iterators that reference it.
42  *
43  * The class template %_Safe_unordered_container simplifies the
44  * construction of @a safe unordered containers that track the iterators
45  * that reference the container, so that the iterators are notified of
46  * changes in the container that may affect their operation, e.g., if
47  * the container invalidates its iterators or is destructed. This class
48  * template may only be used by deriving from it and passing the name
49  * of the derived class as its template parameter via the curiously
50  * recurring template pattern. The derived class must have @c
51  * iterator and @c const_iterator types that are instantiations of
52  * class template _Safe_iterator for this container and @c local_iterator
53  * and @c const_local_iterator types that are instantiations of class
54  * template _Safe_local_iterator for this container. Iterators will
55  * then be tracked automatically.
56  */
57  template<typename _Container>
59  {
60  private:
61  _Container&
62  _M_cont() noexcept
63  { return *static_cast<_Container*>(this); }
64 
65  protected:
66  void
67  _M_invalidate_locals()
68  {
69  auto __local_end = _M_cont()._M_base().end(0);
71  [__local_end](__decltype(_M_cont()._M_base().cend(0)) __it)
72  { return __it != __local_end; });
73  }
74 
75  void
76  _M_invalidate_all()
77  {
78  auto __end = _M_cont()._M_base().end();
79  this->_M_invalidate_if(
80  [__end](__decltype(_M_cont()._M_base().cend()) __it)
81  { return __it != __end; });
82  _M_invalidate_locals();
83  }
84 
85  /** Invalidates all iterators @c x that reference this container,
86  are not singular, and for which @c __pred(x) returns @c
87  true. @c __pred will be invoked with the normal iterators nested
88  in the safe ones. */
89  template<typename _Predicate>
90  void
91  _M_invalidate_if(_Predicate __pred);
92 
93  /** Invalidates all local iterators @c x that reference this container,
94  are not singular, and for which @c __pred(x) returns @c
95  true. @c __pred will be invoked with the normal ilocal iterators
96  nested in the safe ones. */
97  template<typename _Predicate>
98  void
99  _M_invalidate_local_if(_Predicate __pred);
100  };
101 } // namespace __gnu_debug
102 
104 
105 #endif
GNU debug classes for public use.
Base class that supports tracking of local iterators that reference an unordered container.
constexpr auto cend(const _Container &__cont) noexcept(noexcept(std::end(__cont))) -> decltype(std::end(__cont))
Return an iterator pointing to one past the last element of the const container.
Definition: range_access.h:127
Base class for constructing a safe unordered container type that tracks iterators that reference it...