1 // Debugging iterator implementation (out of line) -*- C++ -*- 2 3 // Copyright (C) 2003-2013 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_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 32 namespace __gnu_debug 33 { 34 template<typename _Iterator, typename _Sequence> 35 bool 36 _Safe_iterator<_Iterator, _Sequence>:: _M_can_advance(const difference_type & __n) const37 _M_can_advance(const difference_type& __n) const 38 { 39 typedef typename _Sequence::const_iterator const_debug_iterator; 40 typedef typename const_debug_iterator::iterator_type const_iterator; 41 42 if (this->_M_singular()) 43 return false; 44 if (__n == 0) 45 return true; 46 if (__n < 0) 47 { 48 const_iterator __begin = _M_get_sequence()->_M_base().begin(); 49 std::pair<difference_type, _Distance_precision> __dist = 50 __get_distance(__begin, base()); 51 bool __ok = ((__dist.second == __dp_exact && __dist.first >= -__n) 52 || (__dist.second != __dp_exact && __dist.first > 0)); 53 return __ok; 54 } 55 else 56 { 57 const_iterator __end = _M_get_sequence()->_M_base().end(); 58 std::pair<difference_type, _Distance_precision> __dist = 59 __get_distance(base(), __end); 60 bool __ok = ((__dist.second == __dp_exact && __dist.first >= __n) 61 || (__dist.second != __dp_exact && __dist.first > 0)); 62 return __ok; 63 } 64 } 65 66 template<typename _Iterator, typename _Sequence> 67 template<typename _Other> 68 bool 69 _Safe_iterator<_Iterator, _Sequence>:: _M_valid_range(const _Safe_iterator<_Other,_Sequence> & __rhs) const70 _M_valid_range(const _Safe_iterator<_Other, _Sequence>& __rhs) const 71 { 72 if (!_M_can_compare(__rhs)) 73 return false; 74 75 /* Determine if we can order the iterators without the help of 76 the container */ 77 std::pair<difference_type, _Distance_precision> __dist = 78 __get_distance(base(), __rhs.base()); 79 switch (__dist.second) { 80 case __dp_equality: 81 if (__dist.first == 0) 82 return true; 83 break; 84 85 case __dp_sign: 86 case __dp_exact: 87 return __dist.first >= 0; 88 } 89 90 /* We can only test for equality, but check if one of the 91 iterators is at an extreme. */ 92 /* Optim for classic [begin, it) or [it, end) ranges, limit checks 93 * when code is valid. Note, for the special case of forward_list, 94 * before_begin replaces the role of begin. */ 95 if (_M_is_beginnest() || __rhs._M_is_end()) 96 return true; 97 if (_M_is_end() || __rhs._M_is_beginnest()) 98 return false; 99 100 // Assume that this is a valid range; we can't check anything else 101 return true; 102 } 103 } // namespace __gnu_debug 104 105 #endif 106 107