1// Safe container implementation -*- C++ -*- 2 3// Copyright (C) 2014-2022 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_container.h 26 * This file is a GNU debug extension to the Standard C++ Library. 27 */ 28 29#ifndef _GLIBCXX_DEBUG_SAFE_CONTAINER_H 30#define _GLIBCXX_DEBUG_SAFE_CONTAINER_H 1 31 32#include <ext/alloc_traits.h> 33 34namespace __gnu_debug 35{ 36 /// Safe class dealing with some allocator dependent operations. 37 template<typename _SafeContainer, 38 typename _Alloc, 39 template<typename> class _SafeBase, 40 bool _IsCxx11AllocatorAware = true> 41 class _Safe_container 42 : public _SafeBase<_SafeContainer> 43 { 44 typedef _SafeBase<_SafeContainer> _Base; 45 46 _SafeContainer& 47 _M_cont() _GLIBCXX_NOEXCEPT 48 { return *static_cast<_SafeContainer*>(this); } 49 50 protected: 51#if __cplusplus >= 201103L 52 _Safe_container() = default; 53 _Safe_container(const _Safe_container&) = default; 54 _Safe_container(_Safe_container&&) = default; 55 56 private: 57 _Safe_container(_Safe_container&& __x, const _Alloc&, std::true_type) 58 : _Safe_container(std::move(__x)) 59 { } 60 61 _Safe_container(_Safe_container&& __x, const _Alloc& __a, std::false_type) 62 : _Safe_container() 63 { 64 if (__x._M_cont().get_allocator() == __a) 65 _Base::_M_swap(__x); 66 else 67 __x._M_invalidate_all(); 68 } 69 70 protected: 71 _Safe_container(_Safe_container&& __x, const _Alloc& __a) 72 : _Safe_container(std::move(__x), __a, 73 typename std::allocator_traits<_Alloc>::is_always_equal{}) 74 { } 75#endif 76 77 // Copy assignment invalidate all iterators. 78 _Safe_container& 79 operator=(const _Safe_container&) _GLIBCXX_NOEXCEPT 80 { 81 this->_M_invalidate_all(); 82 return *this; 83 } 84 85#if __cplusplus >= 201103L 86 _Safe_container& 87 operator=(_Safe_container&& __x) noexcept 88 { 89 if (std::__addressof(__x) == this) 90 { 91 // Standard containers have a valid but unspecified value after 92 // self-move, so we invalidate all debug iterators even if the 93 // underlying container happens to preserve its contents. 94 this->_M_invalidate_all(); 95 return *this; 96 } 97 98 if (_IsCxx11AllocatorAware) 99 { 100 typedef __gnu_cxx::__alloc_traits<_Alloc> _Alloc_traits; 101 102 bool __xfer_memory = _Alloc_traits::_S_propagate_on_move_assign() 103 || _M_cont().get_allocator() == __x._M_cont().get_allocator(); 104 if (__xfer_memory) 105 _Base::_M_swap(__x); 106 else 107 this->_M_invalidate_all(); 108 } 109 else 110 _Base::_M_swap(__x); 111 112 __x._M_invalidate_all(); 113 return *this; 114 } 115 116 void 117 _M_swap(_Safe_container& __x) noexcept 118 { 119 if (_IsCxx11AllocatorAware) 120 { 121 typedef __gnu_cxx::__alloc_traits<_Alloc> _Alloc_traits; 122 123 if (!_Alloc_traits::_S_propagate_on_swap()) 124 __glibcxx_check_equal_allocs(this->_M_cont()._M_base(), 125 __x._M_cont()._M_base()); 126 } 127 128 _Base::_M_swap(__x); 129 } 130#endif 131 }; 132 133} // namespace __gnu_debug 134 135#endif 136