1 // Debugging iterator implementation (out of line) -*- C++ -*- 2 3 // Copyright (C) 2003, 2004, 2005, 2006, 2007, 2009, 2010, 2011, 2012 4 // Free Software Foundation, Inc. 5 // 6 // This file is part of the GNU ISO C++ Library. This library is free 7 // software; you can redistribute it and/or modify it under the 8 // terms of the GNU General Public License as published by the 9 // Free Software Foundation; either version 3, or (at your option) 10 // any later version. 11 12 // This library is distributed in the hope that it will be useful, 13 // but WITHOUT ANY WARRANTY; without even the implied warranty of 14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 // GNU General Public License for more details. 16 17 // Under Section 7 of GPL version 3, you are granted additional 18 // permissions described in the GCC Runtime Library Exception, version 19 // 3.1, as published by the Free Software Foundation. 20 21 // You should have received a copy of the GNU General Public License and 22 // a copy of the GCC Runtime Library Exception along with this program; 23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 24 // <http://www.gnu.org/licenses/>. 25 26 /** @file debug/safe_iterator.tcc 27 * This file is a GNU debug extension to the Standard C++ Library. 28 */ 29 30 #ifndef _GLIBCXX_DEBUG_SAFE_ITERATOR_TCC 31 #define _GLIBCXX_DEBUG_SAFE_ITERATOR_TCC 1 32 33 namespace __gnu_debug 34 { 35 template<typename _Iterator, typename _Sequence> 36 bool 37 _Safe_iterator<_Iterator, _Sequence>:: 38 _M_can_advance(const difference_type& __n) const 39 { 40 typedef typename _Sequence::const_iterator const_debug_iterator; 41 typedef typename const_debug_iterator::iterator_type const_iterator; 42 43 if (this->_M_singular()) 44 return false; 45 if (__n == 0) 46 return true; 47 if (__n < 0) 48 { 49 const_iterator __begin = _M_get_sequence()->_M_base().begin(); 50 std::pair<difference_type, _Distance_precision> __dist = 51 __get_distance(__begin, base()); 52 bool __ok = ((__dist.second == __dp_exact && __dist.first >= -__n) 53 || (__dist.second != __dp_exact && __dist.first > 0)); 54 return __ok; 55 } 56 else 57 { 58 const_iterator __end = _M_get_sequence()->_M_base().end(); 59 std::pair<difference_type, _Distance_precision> __dist = 60 __get_distance(base(), __end); 61 bool __ok = ((__dist.second == __dp_exact && __dist.first >= __n) 62 || (__dist.second != __dp_exact && __dist.first > 0)); 63 return __ok; 64 } 65 } 66 67 template<typename _Iterator, typename _Sequence> 68 template<typename _Other> 69 bool 70 _Safe_iterator<_Iterator, _Sequence>:: 71 _M_valid_range(const _Safe_iterator<_Other, _Sequence>& __rhs) const 72 { 73 if (!_M_can_compare(__rhs)) 74 return false; 75 76 /* Determine if we can order the iterators without the help of 77 the container */ 78 std::pair<difference_type, _Distance_precision> __dist = 79 __get_distance(base(), __rhs.base()); 80 switch (__dist.second) { 81 case __dp_equality: 82 if (__dist.first == 0) 83 return true; 84 break; 85 86 case __dp_sign: 87 case __dp_exact: 88 return __dist.first >= 0; 89 } 90 91 /* We can only test for equality, but check if one of the 92 iterators is at an extreme. */ 93 /* Optim for classic [begin, it) or [it, end) ranges, limit checks 94 * when code is valid. Note, for the special case of forward_list, 95 * before_begin replaces the role of begin. */ 96 if (_M_is_beginnest() || __rhs._M_is_end()) 97 return true; 98 if (_M_is_end() || __rhs._M_is_beginnest()) 99 return false; 100 101 // Assume that this is a valid range; we can't check anything else 102 return true; 103 } 104 } // namespace __gnu_debug 105 106 #endif 107 108