1// Safe sequence implementation  -*- C++ -*-
2
3// Copyright (C) 2003, 2004, 2005, 2006, 2009, 2010, 2011
4// Free Software Foundation, Inc.
5//
6// This file is part of the GNU ISO C++ Library.  This library is free
7// software; you can redistribute it and/or modify it under the
8// terms of the GNU General Public License as published by the
9// Free Software Foundation; either version 3, or (at your option)
10// any later version.
11
12// This library is distributed in the hope that it will be useful,
13// but WITHOUT ANY WARRANTY; without even the implied warranty of
14// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15// GNU General Public License for more details.
16
17// Under Section 7 of GPL version 3, you are granted additional
18// permissions described in the GCC Runtime Library Exception, version
19// 3.1, as published by the Free Software Foundation.
20
21// You should have received a copy of the GNU General Public License and
22// a copy of the GCC Runtime Library Exception along with this program;
23// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
24// <http://www.gnu.org/licenses/>.
25
26/** @file debug/safe_sequence.h
27 *  This file is a GNU debug extension to the Standard C++ Library.
28 */
29
30#ifndef _GLIBCXX_DEBUG_SAFE_SEQUENCE_H
31#define _GLIBCXX_DEBUG_SAFE_SEQUENCE_H 1
32
33#include <debug/debug.h>
34#include <debug/macros.h>
35#include <debug/functions.h>
36#include <debug/safe_base.h>
37
38namespace __gnu_debug
39{
40  template<typename _Iterator, typename _Sequence>
41    class _Safe_iterator;
42
43  /** A simple function object that returns true if the passed-in
44   *  value is not equal to the stored value. It saves typing over
45   *  using both bind1st and not_equal.
46   */
47  template<typename _Type>
48    class _Not_equal_to
49    {
50      _Type __value;
51
52    public:
53      explicit _Not_equal_to(const _Type& __v) : __value(__v) { }
54
55      bool
56      operator()(const _Type& __x) const
57      { return __value != __x; }
58    };
59
60  /** A simple function object that returns true if the passed-in
61   *  value is equal to the stored value. */
62  template <typename _Type>
63    class _Equal_to
64    {
65      _Type __value;
66
67    public:
68      explicit _Equal_to(const _Type& __v) : __value(__v) { }
69
70      bool
71      operator()(const _Type& __x) const
72      { return __value == __x; }
73    };
74
75  /** A function object that returns true when the given random access
76      iterator is at least @c n steps away from the given iterator. */
77  template<typename _Iterator>
78    class _After_nth_from
79    {
80      typedef typename std::iterator_traits<_Iterator>::difference_type
81      difference_type;
82
83      _Iterator _M_base;
84      difference_type _M_n;
85
86    public:
87      _After_nth_from(const difference_type& __n, const _Iterator& __base)
88      : _M_base(__base), _M_n(__n) { }
89
90      bool
91      operator()(const _Iterator& __x) const
92      { return __x - _M_base >= _M_n; }
93    };
94
95  /**
96   * @brief Base class for constructing a @a safe sequence type that
97   * tracks iterators that reference it.
98   *
99   * The class template %_Safe_sequence simplifies the construction of
100   * @a safe sequences that track the iterators that reference the
101   * sequence, so that the iterators are notified of changes in the
102   * sequence that may affect their operation, e.g., if the container
103   * invalidates its iterators or is destructed. This class template
104   * may only be used by deriving from it and passing the name of the
105   * derived class as its template parameter via the curiously
106   * recurring template pattern. The derived class must have @c
107   * iterator and @c const_iterator types that are instantiations of
108   * class template _Safe_iterator for this sequence. Iterators will
109   * then be tracked automatically.
110   */
111  template<typename _Sequence>
112    class _Safe_sequence : public _Safe_sequence_base
113    {
114    public:
115      /** Invalidates all iterators @c x that reference this sequence,
116	  are not singular, and for which @c __pred(x) returns @c
117	  true. @c __pred will be invoked with the normal iterators nested
118	  in the safe ones. */
119      template<typename _Predicate>
120        void
121        _M_invalidate_if(_Predicate __pred);
122
123      /** Transfers all iterators @c x that reference @c from sequence,
124	  are not singular, and for which @c __pred(x) returns @c
125	  true. @c __pred will be invoked with the normal iterators nested
126	  in the safe ones. */
127      template<typename _Predicate>
128        void
129        _M_transfer_from_if(_Safe_sequence& __from, _Predicate __pred);
130    };
131} // namespace __gnu_debug
132
133#include <debug/safe_sequence.tcc>
134
135#endif
136