libstdc++-v3/include/debug/safe_sequence.h

   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
  37 namespace __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