summaryrefslogtreecommitdiffstats
path: root/libstdc++-v3/include/debug/safe_iterator.tcc
blob: 7550a1d96baf0b83a7a2acf575a7ec2c024ca36c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
// Debugging iterator implementation (out of line) -*- C++ -*-

// Copyright (C) 2003-2013 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.

// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
// <http://www.gnu.org/licenses/>.

/** @file debug/safe_iterator.tcc
 *  This file is a GNU debug extension to the Standard C++ Library.
 */

#ifndef _GLIBCXX_DEBUG_SAFE_ITERATOR_TCC
#define _GLIBCXX_DEBUG_SAFE_ITERATOR_TCC 1

namespace __gnu_debug
{
  template<typename _Iterator, typename _Sequence>
    bool
    _Safe_iterator<_Iterator, _Sequence>::
    _M_can_advance(const difference_type& __n) const
    {
      if (this->_M_singular())
	return false;
      if (__n == 0)
	return true;
      if (__n < 0)
	{
	  std::pair<difference_type, _Distance_precision> __dist =
	    __get_distance(_M_get_sequence()->_M_base().begin(), base());
	  bool __ok =  ((__dist.second == __dp_exact && __dist.first >= -__n)
			|| (__dist.second != __dp_exact && __dist.first > 0));
	  return __ok;
	}
      else
	{
	  std::pair<difference_type, _Distance_precision> __dist =
	    __get_distance(base(), _M_get_sequence()->_M_base().end());
	  bool __ok = ((__dist.second == __dp_exact && __dist.first >= __n)
		       || (__dist.second != __dp_exact && __dist.first > 0));
	  return __ok;
	}
    }

  template<typename _Iterator, typename _Sequence>
    bool
    _Safe_iterator<_Iterator, _Sequence>::
    _M_valid_range(const _Safe_iterator& __rhs) const
    {
      if (!_M_can_compare(__rhs))
	return false;

      /* Determine if we can order the iterators without the help of
	 the container */
      std::pair<difference_type, _Distance_precision> __dist =
	__get_distance(base(), __rhs.base());
      switch (__dist.second) {
      case __dp_equality:
	if (__dist.first == 0)
	  return true;
	break;

      case __dp_sign:
      case __dp_exact:
	return __dist.first >= 0;
      }

      /* We can only test for equality, but check if one of the
	 iterators is at an extreme. */
      /* Optim for classic [begin, it) or [it, end) ranges, limit checks
       * when code is valid.  Note, for the special case of forward_list,
       * before_begin replaces the role of begin.  */ 
      if (_M_is_beginnest() || __rhs._M_is_end())
	return true;
      if (_M_is_end() || __rhs._M_is_beginnest())
	return false;

      // Assume that this is a valid range; we can't check anything else
      return true;
    }
} // namespace __gnu_debug

#endif

OpenPOWER on IntegriCloud