libstdc++
safe_iterator.tcc
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1// Debugging iterator implementation (out of line) -*- C++ -*-
2
3// Copyright (C) 2003-2017 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_iterator.tcc
26 * This file is a GNU debug extension to the Standard C++ Library.
27 */
28
29#ifndef _GLIBCXX_DEBUG_SAFE_ITERATOR_TCC
30#define _GLIBCXX_DEBUG_SAFE_ITERATOR_TCC 1
31
32namespace __gnu_debug
33{
34 template<typename _Iterator, typename _Sequence>
35 bool
36 _Safe_iterator<_Iterator, _Sequence>::
37 _M_can_advance(const difference_type& __n) const
38 {
39 if (this->_M_singular())
40 return false;
41
42 if (__n == 0)
43 return true;
44
45 if (__n < 0)
46 {
48 __get_distance_from_begin(*this);
49 bool __ok = ((__dist.second == __dp_exact && __dist.first >= -__n)
50 || (__dist.second != __dp_exact && __dist.first > 0));
51 return __ok;
52 }
53 else
54 {
56 __get_distance_to_end(*this);
57 bool __ok = ((__dist.second == __dp_exact && __dist.first >= __n)
58 || (__dist.second != __dp_exact && __dist.first > 0));
59 return __ok;
60 }
61 }
62
63 template<typename _Iterator, typename _Sequence>
64 bool
65 _Safe_iterator<_Iterator, _Sequence>::
66 _M_valid_range(const _Safe_iterator& __rhs,
68 bool __check_dereferenceable) const
69 {
70 if (!_M_can_compare(__rhs))
71 return false;
72
73 /* Determine iterators order */
74 __dist = __get_distance(*this, __rhs);
75 switch (__dist.second)
76 {
77 case __dp_equality:
78 if (__dist.first == 0)
79 return true;
80 break;
81
82 case __dp_sign:
83 case __dp_exact:
84 // If range is not empty first iterator must be dereferenceable.
85 if (__dist.first > 0)
86 return !__check_dereferenceable || _M_dereferenceable();
87 return __dist.first == 0;
88 }
89
90 // Assume that this is a valid range; we can't check anything else.
91 return true;
92 }
93} // namespace __gnu_debug
94
95#endif
GNU debug classes for public use.
bool __check_dereferenceable(const _Iterator &)
Definition: functions.h:74
_Distance_traits< _Iterator >::__type __get_distance(const _Iterator &__lhs, const _Iterator &__rhs, std::random_access_iterator_tag)
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:199
_T1 first
second_type is the second bound type
Definition: stl_pair.h:203
_T2 second
first is a copy of the first object
Definition: stl_pair.h:204