1// Safe sequence implementation  -*- C++ -*-
2
3// Copyright (C) 2003-2013 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_sequence.h
26 *  This file is a GNU debug extension to the Standard C++ Library.
27 */
28
29#ifndef _GLIBCXX_DEBUG_SAFE_SEQUENCE_H
30#define _GLIBCXX_DEBUG_SAFE_SEQUENCE_H 1
31
32#include <debug/debug.h>
33#include <debug/macros.h>
34#include <debug/functions.h>
35#include <debug/safe_base.h>
36
37namespace __gnu_debug
38{
39  template<typename _Iterator, typename _Sequence>
40    class _Safe_iterator;
41
42  /** A simple function object that returns true if the passed-in
43   *  value is not equal to the stored value. It saves typing over
44   *  using both bind1st and not_equal.
45   */
46  template<typename _Type>
47    class _Not_equal_to
48    {
49      _Type __value;
50
51    public:
52      explicit _Not_equal_to(const _Type& __v) : __value(__v) { }
53
54      bool
55      operator()(const _Type& __x) const
56      { return __value != __x; }
57    };
58
59  /** A simple function object that returns true if the passed-in
60   *  value is equal to the stored value. */
61  template <typename _Type>
62    class _Equal_to
63    {
64      _Type __value;
65
66    public:
67      explicit _Equal_to(const _Type& __v) : __value(__v) { }
68
69      bool
70      operator()(const _Type& __x) const
71      { return __value == __x; }
72    };
73
74  /** A function object that returns true when the given random access
75      iterator is at least @c n steps away from the given iterator. */
76  template<typename _Iterator>
77    class _After_nth_from
78    {
79      typedef typename std::iterator_traits<_Iterator>::difference_type
80      difference_type;
81
82      _Iterator _M_base;
83      difference_type _M_n;
84
85    public:
86      _After_nth_from(const difference_type& __n, const _Iterator& __base)
87      : _M_base(__base), _M_n(__n) { }
88
89      bool
90      operator()(const _Iterator& __x) const
91      { return __x - _M_base >= _M_n; }
92    };
93
94  /**
95   * @brief Base class for constructing a @a safe sequence type that
96   * tracks iterators that reference it.
97   *
98   * The class template %_Safe_sequence simplifies the construction of
99   * @a safe sequences that track the iterators that reference the
100   * sequence, so that the iterators are notified of changes in the
101   * sequence that may affect their operation, e.g., if the container
102   * invalidates its iterators or is destructed. This class template
103   * may only be used by deriving from it and passing the name of the
104   * derived class as its template parameter via the curiously
105   * recurring template pattern. The derived class must have @c
106   * iterator and @c const_iterator types that are instantiations of
107   * class template _Safe_iterator for this sequence. Iterators will
108   * then be tracked automatically.
109   */
110  template<typename _Sequence>
111    class _Safe_sequence : public _Safe_sequence_base
112    {
113    public:
114      /** Invalidates all iterators @c x that reference this sequence,
115	  are not singular, and for which @c __pred(x) returns @c
116	  true. @c __pred will be invoked with the normal iterators nested
117	  in the safe ones. */
118      template<typename _Predicate>
119        void
120        _M_invalidate_if(_Predicate __pred);
121
122      /** Transfers all iterators @c x that reference @c from sequence,
123	  are not singular, and for which @c __pred(x) returns @c
124	  true. @c __pred will be invoked with the normal iterators nested
125	  in the safe ones. */
126      template<typename _Predicate>
127        void
128        _M_transfer_from_if(_Safe_sequence& __from, _Predicate __pred);
129    };
130} // namespace __gnu_debug
131
132#include <debug/safe_sequence.tcc>
133
134#endif
135