| // Safe iterator implementation -*- C++ -*- |
| |
| // Copyright (C) 2011-2015 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_local_iterator.h |
| * This file is a GNU debug extension to the Standard C++ Library. |
| */ |
| |
| #ifndef _GLIBCXX_DEBUG_SAFE_LOCAL_ITERATOR_H |
| #define _GLIBCXX_DEBUG_SAFE_LOCAL_ITERATOR_H 1 |
| |
| #include <debug/debug.h> |
| #include <debug/macros.h> |
| #include <debug/functions.h> |
| #include <debug/safe_unordered_base.h> |
| #include <ext/type_traits.h> |
| |
| namespace __gnu_debug |
| { |
| /** \brief Safe iterator wrapper. |
| * |
| * The class template %_Safe_local_iterator is a wrapper around an |
| * iterator that tracks the iterator's movement among sequences and |
| * checks that operations performed on the "safe" iterator are |
| * legal. In additional to the basic iterator operations (which are |
| * validated, and then passed to the underlying iterator), |
| * %_Safe_local_iterator has member functions for iterator invalidation, |
| * attaching/detaching the iterator from sequences, and querying |
| * the iterator's state. |
| */ |
| template<typename _Iterator, typename _Sequence> |
| class _Safe_local_iterator |
| : private _Iterator |
| , public _Safe_local_iterator_base |
| { |
| typedef _Iterator _Iter_base; |
| typedef _Safe_local_iterator_base _Safe_base; |
| typedef typename _Sequence::const_local_iterator _Const_local_iterator; |
| typedef typename _Sequence::size_type size_type; |
| |
| /// Determine if this is a constant iterator. |
| bool |
| _M_constant() const |
| { |
| return std::__are_same<_Const_local_iterator, |
| _Safe_local_iterator>::__value; |
| } |
| |
| typedef std::iterator_traits<_Iterator> _Traits; |
| |
| struct _Attach_single |
| { }; |
| |
| _Safe_local_iterator(const _Iterator& __i, _Safe_sequence_base* __cont, |
| _Attach_single) noexcept |
| : _Iter_base(__i) |
| { _M_attach_single(__cont); } |
| |
| public: |
| typedef _Iterator iterator_type; |
| typedef typename _Traits::iterator_category iterator_category; |
| typedef typename _Traits::value_type value_type; |
| typedef typename _Traits::difference_type difference_type; |
| typedef typename _Traits::reference reference; |
| typedef typename _Traits::pointer pointer; |
| |
| /// @post the iterator is singular and unattached |
| _Safe_local_iterator() noexcept : _Iter_base() { } |
| |
| /** |
| * @brief Safe iterator construction from an unsafe iterator and |
| * its sequence. |
| * |
| * @pre @p seq is not NULL |
| * @post this is not singular |
| */ |
| _Safe_local_iterator(const _Iterator& __i, |
| const _Safe_sequence_base* __cont) |
| : _Iter_base(__i), _Safe_base(__cont, _M_constant()) |
| { |
| _GLIBCXX_DEBUG_VERIFY(!this->_M_singular(), |
| _M_message(__msg_init_singular) |
| ._M_iterator(*this, "this")); |
| } |
| |
| /** |
| * @brief Copy construction. |
| */ |
| _Safe_local_iterator(const _Safe_local_iterator& __x) noexcept |
| : _Iter_base(__x.base()) |
| { |
| // _GLIBCXX_RESOLVE_LIB_DEFECTS |
| // DR 408. Is vector<reverse_iterator<char*> > forbidden? |
| _GLIBCXX_DEBUG_VERIFY(!__x._M_singular() |
| || __x.base() == _Iterator(), |
| _M_message(__msg_init_copy_singular) |
| ._M_iterator(*this, "this") |
| ._M_iterator(__x, "other")); |
| _M_attach(__x._M_sequence); |
| } |
| |
| /** |
| * @brief Move construction. |
| * @post __x is singular and unattached |
| */ |
| _Safe_local_iterator(_Safe_local_iterator&& __x) noexcept |
| : _Iter_base() |
| { |
| _GLIBCXX_DEBUG_VERIFY(!__x._M_singular() |
| || __x.base() == _Iterator(), |
| _M_message(__msg_init_copy_singular) |
| ._M_iterator(*this, "this") |
| ._M_iterator(__x, "other")); |
| auto __cont = __x._M_sequence; |
| __x._M_detach(); |
| std::swap(base(), __x.base()); |
| _M_attach(__cont); |
| } |
| |
| /** |
| * @brief Converting constructor from a mutable iterator to a |
| * constant iterator. |
| */ |
| template<typename _MutableIterator> |
| _Safe_local_iterator( |
| const _Safe_local_iterator<_MutableIterator, |
| typename __gnu_cxx::__enable_if<std::__are_same< |
| _MutableIterator, |
| typename _Sequence::local_iterator::iterator_type>::__value, |
| _Sequence>::__type>& __x) |
| : _Iter_base(__x.base()) |
| { |
| // _GLIBCXX_RESOLVE_LIB_DEFECTS |
| // DR 408. Is vector<reverse_iterator<char*> > forbidden? |
| _GLIBCXX_DEBUG_VERIFY(!__x._M_singular() |
| || __x.base() == _Iterator(), |
| _M_message(__msg_init_const_singular) |
| ._M_iterator(*this, "this") |
| ._M_iterator(__x, "other")); |
| _M_attach(__x._M_sequence); |
| } |
| |
| /** |
| * @brief Copy assignment. |
| */ |
| _Safe_local_iterator& |
| operator=(const _Safe_local_iterator& __x) |
| { |
| // _GLIBCXX_RESOLVE_LIB_DEFECTS |
| // DR 408. Is vector<reverse_iterator<char*> > forbidden? |
| _GLIBCXX_DEBUG_VERIFY(!__x._M_singular() |
| || __x.base() == _Iterator(), |
| _M_message(__msg_copy_singular) |
| ._M_iterator(*this, "this") |
| ._M_iterator(__x, "other")); |
| |
| if (this->_M_sequence && this->_M_sequence == __x._M_sequence) |
| { |
| __gnu_cxx::__scoped_lock __l(this->_M_get_mutex()); |
| base() = __x.base(); |
| _M_version = __x._M_sequence->_M_version; |
| } |
| else |
| { |
| _M_detach(); |
| base() = __x.base(); |
| _M_attach(__x._M_sequence); |
| } |
| |
| return *this; |
| } |
| |
| /** |
| * @brief Move assignment. |
| * @post __x is singular and unattached |
| */ |
| _Safe_local_iterator& |
| operator=(_Safe_local_iterator&& __x) noexcept |
| { |
| _GLIBCXX_DEBUG_VERIFY(this != &__x, |
| _M_message(__msg_self_move_assign) |
| ._M_iterator(*this, "this")); |
| _GLIBCXX_DEBUG_VERIFY(!__x._M_singular() |
| || __x.base() == _Iterator(), |
| _M_message(__msg_copy_singular) |
| ._M_iterator(*this, "this") |
| ._M_iterator(__x, "other")); |
| |
| if (this->_M_sequence && this->_M_sequence == __x._M_sequence) |
| { |
| __gnu_cxx::__scoped_lock __l(this->_M_get_mutex()); |
| base() = __x.base(); |
| _M_version = __x._M_sequence->_M_version; |
| } |
| else |
| { |
| _M_detach(); |
| base() = __x.base(); |
| _M_attach(__x._M_sequence); |
| } |
| |
| __x._M_detach(); |
| __x.base() = _Iterator(); |
| return *this; |
| } |
| |
| /** |
| * @brief Iterator dereference. |
| * @pre iterator is dereferenceable |
| */ |
| reference |
| operator*() const |
| { |
| _GLIBCXX_DEBUG_VERIFY(this->_M_dereferenceable(), |
| _M_message(__msg_bad_deref) |
| ._M_iterator(*this, "this")); |
| return *base(); |
| } |
| |
| /** |
| * @brief Iterator dereference. |
| * @pre iterator is dereferenceable |
| * @todo Make this correct w.r.t. iterators that return proxies |
| */ |
| pointer |
| operator->() const |
| { |
| _GLIBCXX_DEBUG_VERIFY(this->_M_dereferenceable(), |
| _M_message(__msg_bad_deref) |
| ._M_iterator(*this, "this")); |
| return std::__addressof(*base()); |
| } |
| |
| // ------ Input iterator requirements ------ |
| /** |
| * @brief Iterator preincrement |
| * @pre iterator is incrementable |
| */ |
| _Safe_local_iterator& |
| operator++() |
| { |
| _GLIBCXX_DEBUG_VERIFY(this->_M_incrementable(), |
| _M_message(__msg_bad_inc) |
| ._M_iterator(*this, "this")); |
| __gnu_cxx::__scoped_lock __l(this->_M_get_mutex()); |
| ++base(); |
| return *this; |
| } |
| |
| /** |
| * @brief Iterator postincrement |
| * @pre iterator is incrementable |
| */ |
| _Safe_local_iterator |
| operator++(int) |
| { |
| _GLIBCXX_DEBUG_VERIFY(this->_M_incrementable(), |
| _M_message(__msg_bad_inc) |
| ._M_iterator(*this, "this")); |
| __gnu_cxx::__scoped_lock __l(this->_M_get_mutex()); |
| return _Safe_local_iterator(base()++, this->_M_sequence, |
| _Attach_single()); |
| } |
| |
| // ------ Utilities ------ |
| /** |
| * @brief Return the underlying iterator |
| */ |
| _Iterator& |
| base() noexcept { return *this; } |
| |
| const _Iterator& |
| base() const noexcept { return *this; } |
| |
| /** |
| * @brief Return the bucket |
| */ |
| size_type |
| bucket() const { return base()._M_get_bucket(); } |
| |
| /** |
| * @brief Conversion to underlying non-debug iterator to allow |
| * better interaction with non-debug containers. |
| */ |
| operator _Iterator() const { return *this; } |
| |
| /** Attach iterator to the given sequence. */ |
| void |
| _M_attach(_Safe_sequence_base* __seq) |
| { _Safe_base::_M_attach(__seq, _M_constant()); } |
| |
| /** Likewise, but not thread-safe. */ |
| void |
| _M_attach_single(_Safe_sequence_base* __seq) |
| { _Safe_base::_M_attach_single(__seq, _M_constant()); } |
| |
| /// Is the iterator dereferenceable? |
| bool |
| _M_dereferenceable() const |
| { return !this->_M_singular() && !_M_is_end(); } |
| |
| /// Is the iterator incrementable? |
| bool |
| _M_incrementable() const |
| { return !this->_M_singular() && !_M_is_end(); } |
| |
| // Is the iterator range [*this, __rhs) valid? |
| bool |
| _M_valid_range(const _Safe_local_iterator& __rhs) const; |
| |
| // The sequence this iterator references. |
| typename |
| __gnu_cxx::__conditional_type<std::__are_same<_Const_local_iterator, |
| _Safe_local_iterator>::__value, |
| const _Sequence*, |
| _Sequence*>::__type |
| _M_get_sequence() const |
| { return static_cast<_Sequence*>(_M_sequence); } |
| |
| /// Is this iterator equal to the sequence's begin(bucket) iterator? |
| bool _M_is_begin() const |
| { return base() == _M_get_sequence()->_M_base().begin(bucket()); } |
| |
| /// Is this iterator equal to the sequence's end(bucket) iterator? |
| bool _M_is_end() const |
| { return base() == _M_get_sequence()->_M_base().end(bucket()); } |
| |
| /// Is this iterator part of the same bucket as the other one? |
| template<typename _Other> |
| bool |
| _M_in_same_bucket(const _Safe_local_iterator<_Other, |
| _Sequence>& __other) const |
| { return bucket() == __other.bucket(); } |
| }; |
| |
| template<typename _IteratorL, typename _IteratorR, typename _Sequence> |
| inline bool |
| operator==(const _Safe_local_iterator<_IteratorL, _Sequence>& __lhs, |
| const _Safe_local_iterator<_IteratorR, _Sequence>& __rhs) |
| { |
| _GLIBCXX_DEBUG_VERIFY(!__lhs._M_singular() && !__rhs._M_singular(), |
| _M_message(__msg_iter_compare_bad) |
| ._M_iterator(__lhs, "lhs") |
| ._M_iterator(__rhs, "rhs")); |
| _GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs), |
| _M_message(__msg_compare_different) |
| ._M_iterator(__lhs, "lhs") |
| ._M_iterator(__rhs, "rhs")); |
| _GLIBCXX_DEBUG_VERIFY(__lhs._M_in_same_bucket(__rhs), |
| _M_message(__msg_local_iter_compare_bad) |
| ._M_iterator(__lhs, "lhs") |
| ._M_iterator(__rhs, "rhs")); |
| return __lhs.base() == __rhs.base(); |
| } |
| |
| template<typename _Iterator, typename _Sequence> |
| inline bool |
| operator==(const _Safe_local_iterator<_Iterator, _Sequence>& __lhs, |
| const _Safe_local_iterator<_Iterator, _Sequence>& __rhs) |
| { |
| _GLIBCXX_DEBUG_VERIFY(!__lhs._M_singular() && !__rhs._M_singular(), |
| _M_message(__msg_iter_compare_bad) |
| ._M_iterator(__lhs, "lhs") |
| ._M_iterator(__rhs, "rhs")); |
| _GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs), |
| _M_message(__msg_compare_different) |
| ._M_iterator(__lhs, "lhs") |
| ._M_iterator(__rhs, "rhs")); |
| _GLIBCXX_DEBUG_VERIFY(__lhs._M_in_same_bucket(__rhs), |
| _M_message(__msg_local_iter_compare_bad) |
| ._M_iterator(__lhs, "lhs") |
| ._M_iterator(__rhs, "rhs")); |
| return __lhs.base() == __rhs.base(); |
| } |
| |
| template<typename _IteratorL, typename _IteratorR, typename _Sequence> |
| inline bool |
| operator!=(const _Safe_local_iterator<_IteratorL, _Sequence>& __lhs, |
| const _Safe_local_iterator<_IteratorR, _Sequence>& __rhs) |
| { |
| _GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(), |
| _M_message(__msg_iter_compare_bad) |
| ._M_iterator(__lhs, "lhs") |
| ._M_iterator(__rhs, "rhs")); |
| _GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs), |
| _M_message(__msg_compare_different) |
| ._M_iterator(__lhs, "lhs") |
| ._M_iterator(__rhs, "rhs")); |
| _GLIBCXX_DEBUG_VERIFY(__lhs._M_in_same_bucket(__rhs), |
| _M_message(__msg_local_iter_compare_bad) |
| ._M_iterator(__lhs, "lhs") |
| ._M_iterator(__rhs, "rhs")); |
| return __lhs.base() != __rhs.base(); |
| } |
| |
| template<typename _Iterator, typename _Sequence> |
| inline bool |
| operator!=(const _Safe_local_iterator<_Iterator, _Sequence>& __lhs, |
| const _Safe_local_iterator<_Iterator, _Sequence>& __rhs) |
| { |
| _GLIBCXX_DEBUG_VERIFY(!__lhs._M_singular() && !__rhs._M_singular(), |
| _M_message(__msg_iter_compare_bad) |
| ._M_iterator(__lhs, "lhs") |
| ._M_iterator(__rhs, "rhs")); |
| _GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs), |
| _M_message(__msg_compare_different) |
| ._M_iterator(__lhs, "lhs") |
| ._M_iterator(__rhs, "rhs")); |
| _GLIBCXX_DEBUG_VERIFY(__lhs._M_in_same_bucket(__rhs), |
| _M_message(__msg_local_iter_compare_bad) |
| ._M_iterator(__lhs, "lhs") |
| ._M_iterator(__rhs, "rhs")); |
| return __lhs.base() != __rhs.base(); |
| } |
| } // namespace __gnu_debug |
| |
| #include <debug/safe_local_iterator.tcc> |
| |
| #endif |