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Editing: safe_unordered_base.h
// Safe container/iterator base implementation -*- C++ -*- // Copyright (C) 2011-2018 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_unordered_base.h * This file is a GNU debug extension to the Standard C++ Library. */ #ifndef _GLIBCXX_DEBUG_SAFE_UNORDERED_BASE_H #define _GLIBCXX_DEBUG_SAFE_UNORDERED_BASE_H 1 #include <debug/safe_base.h> namespace __gnu_debug { class _Safe_unordered_container_base; /** \brief Basic functionality for a @a safe iterator. * * The %_Safe_local_iterator_base base class implements the functionality * of a safe local iterator that is not specific to a particular iterator * type. It contains a pointer back to the container it references * along with iterator version information and pointers to form a * doubly-linked list of local iterators referenced by the container. * * This class must not perform any operations that can throw an * exception, or the exception guarantees of derived iterators will * be broken. */ class _Safe_local_iterator_base : public _Safe_iterator_base { protected: /** Initializes the iterator and makes it singular. */ _Safe_local_iterator_base() { } /** Initialize the iterator to reference the container pointed to * by @p __seq. @p __constant is true when we are initializing a * constant local iterator, and false if it is a mutable local iterator. * Note that @p __seq may be NULL, in which case the iterator will be * singular. Otherwise, the iterator will reference @p __seq and * be nonsingular. */ _Safe_local_iterator_base(const _Safe_sequence_base* __seq, bool __constant) { this->_M_attach(const_cast<_Safe_sequence_base*>(__seq), __constant); } /** Initializes the iterator to reference the same container that @p __x does. @p __constant is true if this is a constant iterator, and false if it is mutable. */ _Safe_local_iterator_base(const _Safe_local_iterator_base& __x, bool __constant) { this->_M_attach(__x._M_sequence, __constant); } ~_Safe_local_iterator_base() { this->_M_detach(); } _Safe_unordered_container_base* _M_get_container() const noexcept; /** Attaches this iterator to the given container, detaching it * from whatever container it was attached to originally. If the * new container is the NULL pointer, the iterator is left * unattached. */ void _M_attach(_Safe_sequence_base* __seq, bool __constant); /** Likewise, but not thread-safe. */ void _M_attach_single(_Safe_sequence_base* __seq, bool __constant) throw (); /** Detach the iterator for whatever container it is attached to, * if any. */ void _M_detach(); /** Likewise, but not thread-safe. */ void _M_detach_single() throw (); }; /** * @brief Base class that supports tracking of local iterators that * reference an unordered container. * * The %_Safe_unordered_container_base class provides basic support for * tracking iterators into an unordered container. Containers that track * iterators must derived from %_Safe_unordered_container_base publicly, so * that safe iterators (which inherit _Safe_iterator_base) can * attach to them. This class contains four linked lists of * iterators, one for constant iterators, one for mutable * iterators, one for constant local iterators, one for mutable local * iterators and a version number that allows very fast * invalidation of all iterators that reference the container. * * This class must ensure that no operation on it may throw an * exception, otherwise @a safe containers may fail to provide the * exception-safety guarantees required by the C++ standard. */ class _Safe_unordered_container_base : public _Safe_sequence_base { friend class _Safe_local_iterator_base; typedef _Safe_sequence_base _Base; public: /// The list of mutable local iterators that reference this container _Safe_iterator_base* _M_local_iterators; /// The list of constant local iterators that reference this container _Safe_iterator_base* _M_const_local_iterators; protected: // Initialize with a version number of 1 and no iterators _Safe_unordered_container_base() noexcept : _M_local_iterators(nullptr), _M_const_local_iterators(nullptr) { } // Copy constructor does not copy iterators. _Safe_unordered_container_base(const _Safe_unordered_container_base&) noexcept : _Safe_unordered_container_base() { } // When moved unordered containers iterators are swapped. _Safe_unordered_container_base(_Safe_unordered_container_base&& __x) noexcept : _Safe_unordered_container_base() { this->_M_swap(__x); } /** Notify all iterators that reference this container that the container is being destroyed. */ ~_Safe_unordered_container_base() noexcept { this->_M_detach_all(); } /** Detach all iterators, leaving them singular. */ void _M_detach_all(); /** Swap this container with the given container. This operation * also swaps ownership of the iterators, so that when the * operation is complete all iterators that originally referenced * one container now reference the other container. */ void _M_swap(_Safe_unordered_container_base& __x) noexcept; private: /** Attach an iterator to this container. */ void _M_attach_local(_Safe_iterator_base* __it, bool __constant); /** Likewise but not thread safe. */ void _M_attach_local_single(_Safe_iterator_base* __it, bool __constant) throw (); /** Detach an iterator from this container */ void _M_detach_local(_Safe_iterator_base* __it); /** Likewise but not thread safe. */ void _M_detach_local_single(_Safe_iterator_base* __it) throw (); }; } // namespace __gnu_debug #endif
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