libstdc++
safe_local_iterator.tcc
Go to the documentation of this file.
00001 // Debugging iterator implementation (out of line) -*- C++ -*-
00002 
00003 // Copyright (C) 2011-2019 Free Software Foundation, Inc.
00004 //
00005 // This file is part of the GNU ISO C++ Library.  This library is free
00006 // software; you can redistribute it and/or modify it under the
00007 // terms of the GNU General Public License as published by the
00008 // Free Software Foundation; either version 3, or (at your option)
00009 // any later version.
00010 
00011 // This library is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 
00016 // Under Section 7 of GPL version 3, you are granted additional
00017 // permissions described in the GCC Runtime Library Exception, version
00018 // 3.1, as published by the Free Software Foundation.
00019 
00020 // You should have received a copy of the GNU General Public License and
00021 // a copy of the GCC Runtime Library Exception along with this program;
00022 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00023 // <http://www.gnu.org/licenses/>.
00024 
00025 /** @file debug/safe_local_iterator.tcc
00026  *  This file is a GNU debug extension to the Standard C++ Library.
00027  */
00028 
00029 #ifndef _GLIBCXX_DEBUG_SAFE_LOCAL_ITERATOR_TCC
00030 #define _GLIBCXX_DEBUG_SAFE_LOCAL_ITERATOR_TCC 1
00031 
00032 namespace __gnu_debug
00033 {
00034   template<typename _Iterator, typename _Sequence>
00035     typename _Distance_traits<_Iterator>::__type
00036     _Safe_local_iterator<_Iterator, _Sequence>::
00037     _M_get_distance_to(const _Safe_local_iterator& __rhs) const
00038     {
00039       if (base() == __rhs.base())
00040         return { 0, __dp_exact };
00041 
00042       if (_M_is_begin())
00043         {
00044           if (__rhs._M_is_end())
00045             return
00046               {
00047                 _M_get_sequence()->bucket_size(bucket()),
00048                 __dp_exact
00049               };
00050 
00051           return { 1, __dp_sign };
00052         }
00053 
00054       if (_M_is_end())
00055         {
00056           if (__rhs._M_is_begin())
00057             return
00058               {
00059                 -_M_get_sequence()->bucket_size(bucket()),
00060                 __dp_exact
00061               };
00062 
00063           return { -1, __dp_sign };
00064         }
00065 
00066       if (__rhs._M_is_begin())
00067         return { -1, __dp_sign };
00068 
00069       if (__rhs._M_is_end())
00070         return { 1, __dp_sign };
00071 
00072       return { 1, __dp_equality };
00073     }
00074 
00075   template<typename _Iterator, typename _Sequence>
00076     bool
00077     _Safe_local_iterator<_Iterator, _Sequence>::
00078     _M_valid_range(const _Safe_local_iterator& __rhs,
00079                 std::pair<difference_type, _Distance_precision>& __dist) const
00080     {
00081       if (!_M_can_compare(__rhs))
00082         return false;
00083 
00084       if (bucket() != __rhs.bucket())
00085         return false;
00086 
00087       /* Determine if we can order the iterators without the help of
00088          the container */
00089       __dist = _M_get_distance_to(__rhs);
00090       switch (__dist.second)
00091         {
00092         case __dp_equality:
00093           if (__dist.first == 0)
00094             return true;
00095           break;
00096 
00097         case __dp_sign:
00098         case __dp_exact:
00099           return __dist.first >= 0;
00100         }
00101 
00102       // Assume that this is a valid range; we can't check anything else
00103       return true;
00104     }
00105 } // namespace __gnu_debug
00106 
00107 #endif