libstdc++

safe_local_iterator.tcc
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1 // Debugging iterator implementation (out of line) -*- C++ -*-
2
3 // Copyright (C) 2011-2013 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_local_iterator.tcc
26 * This file is a GNU debug extension to the Standard C++ Library.
27 */
28
29 #ifndef _GLIBCXX_DEBUG_SAFE_LOCAL_ITERATOR_TCC
30 #define _GLIBCXX_DEBUG_SAFE_LOCAL_ITERATOR_TCC 1
31
32 namespace __gnu_debug
33 {
34 template<typename _Iterator, typename _Sequence>
35 template<typename _Other>
36 bool
37 _Safe_local_iterator<_Iterator, _Sequence>::
38 _M_valid_range(const _Safe_local_iterator<_Other, _Sequence>& __rhs) const
39 {
40 if (!_M_can_compare(__rhs))
41 return false;
42 if (_M_bucket != __rhs._M_bucket)
43 return false;
44
45 /* Determine if we can order the iterators without the help of
46 the container */
47 std::pair<difference_type, _Distance_precision> __dist =
48 __get_distance(base(), __rhs.base());
49 switch (__dist.second)
50 {
51 case __dp_equality:
52 if (__dist.first == 0)
53 return true;
54 break;
55
56 case __dp_sign:
57 case __dp_exact:
58 return __dist.first >= 0;
59 }
60
61 /* We can only test for equality, but check if one of the
62 iterators is at an extreme. */
63 /* Optim for classic [begin, it) or [it, end) ranges, limit checks
64 * when code is valid. */
65 if (_M_is_begin() || __rhs._M_is_end())
66 return true;
67 if (_M_is_end() || __rhs._M_is_begin())
68 return false;
69
70 // Assume that this is a valid range; we can't check anything else
71 return true;
72 }
73 } // namespace __gnu_debug
74
75 #endif