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

   1 // Safe sequence implementation  -*- C++ -*-
   2
   3 // Copyright (C) 2003, 2004, 2005, 2006, 2009, 2010
   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
  38 namespace __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 @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 #ifndef _GLIBCXX_EXPORT_TEMPLATE
 134 #  include <debug/safe_sequence.tcc>
 135 #endif
 136
 137 #endif