1 // Debugging iterator implementation (out of line) -*- C++ -*-
2 
3 // Copyright (C) 2003, 2004
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 2, 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 // You should have received a copy of the GNU General Public License along
18 // with this library; see the file COPYING.  If not, write to the Free
19 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
20 // USA.
21 
22 // As a special exception, you may use this file as part of a free software
23 // library without restriction.  Specifically, if other files instantiate
24 // templates or use macros or inline functions from this file, or you compile
25 // this file and link it with other files to produce an executable, this
26 // file does not by itself cause the resulting executable to be covered by
27 // the GNU General Public License.  This exception does not however
28 // invalidate any other reasons why the executable file might be covered by
29 // the GNU General Public License.
30 
31 /** @file safe_iterator.tcc
32  *  This is an internal header file, included by other library headers.
33  *  You should not attempt to use it directly.
34  */
35 
36 #ifndef _GLIBCXX_DEBUG_SAFE_ITERATOR_TCC
37 #define _GLIBCXX_DEBUG_SAFE_ITERATOR_TCC 1
38 
39 namespace __gnu_debug
40 {
41   template<typename _Iterator, typename _Sequence>
42     bool
43     _Safe_iterator<_Iterator, _Sequence>::
44     _M_can_advance(const difference_type& __n) const
45     {
46       typedef typename _Sequence::const_iterator const_iterator;
47 
48       if (this->_M_singular())
49 	return false;
50       if (__n == 0)
51 	return true;
52       if (__n < 0)
53 	{
54 	  const_iterator __begin =
55 	    static_cast<const _Sequence*>(_M_sequence)->begin();
56 	  pair<difference_type, _Distance_precision> __dist =
57 	    this->_M_get_distance(__begin, *this);
58 	  bool __ok =  (__dist.second == __dp_exact && __dist.first >= -__n
59 			|| __dist.second != __dp_exact && __dist.first > 0);
60 	  return __ok;
61 	}
62       else
63 	{
64 	  const_iterator __end =
65 	    static_cast<const _Sequence*>(_M_sequence)->end();
66 	  pair<difference_type, _Distance_precision> __dist =
67 	    this->_M_get_distance(*this, __end);
68 	  bool __ok = (__dist.second == __dp_exact && __dist.first >= __n
69 		       || __dist.second != __dp_exact && __dist.first > 0);
70 	  return __ok;
71 	}
72     }
73 
74   template<typename _Iterator, typename _Sequence>
75     template<typename _Other>
76       bool
77       _Safe_iterator<_Iterator, _Sequence>::
78       _M_valid_range(const _Safe_iterator<_Other, _Sequence>& __rhs) const
79       {
80 	if (!_M_can_compare(__rhs))
81 	  return false;
82 
83 	/* Determine if we can order the iterators without the help of
84 	   the container */
85 	pair<difference_type, _Distance_precision> __dist =
86 	  this->_M_get_distance(*this, __rhs);
87 	switch (__dist.second) {
88 	case __dp_equality:
89 	  if (__dist.first == 0)
90 	    return true;
91 	  break;
92 
93 	case __dp_sign:
94 	case __dp_exact:
95 	  return __dist.first >= 0;
96 	}
97 
98 	/* We can only test for equality, but check if one of the
99 	   iterators is at an extreme. */
100 	if (_M_is_begin() || __rhs._M_is_end())
101 	  return true;
102 	else if (_M_is_end() || __rhs._M_is_begin())
103 	  return false;
104 
105 	// Assume that this is a valid range; we can't check anything else
106 	return true;
107       }
108 
109   template<typename _Iterator, typename _Sequence>
110     void
111     _Safe_iterator<_Iterator, _Sequence>::
112     _M_invalidate()
113     {
114       typedef typename _Sequence::iterator iterator;
115       typedef typename _Sequence::const_iterator const_iterator;
116 
117       if (!this->_M_singular())
118 	{
119 	  for (_Safe_iterator_base* iter = _M_sequence->_M_iterators; iter; )
120 	    {
121 	      iterator* __victim = static_cast<iterator*>(iter);
122 	      iter = iter->_M_next;
123 	      if (this->base() == __victim->base())
124 		__victim->_M_version = 0;
125 	    }
126 	  for (_Safe_iterator_base* iter2 = _M_sequence->_M_const_iterators;
127 	       iter2; /* increment in loop */)
128 	    {
129 	      const_iterator* __victim = static_cast<const_iterator*>(iter2);
130 	      iter2 = iter2->_M_next;
131 	      if (this->base() == __victim->base())
132 		__victim->_M_version = 0;
133 	    }
134 	  _M_version = 0;
135 	}
136     }
137 } // namespace __gnu_debug
138 
139 #endif
140 
141