3 #ifndef __CDS_CONTAINER_MICHAEL_KVLIST_NOGC_H
4 #define __CDS_CONTAINER_MICHAEL_KVLIST_NOGC_H
7 #include <cds/container/details/michael_list_base.h>
8 #include <cds/intrusive/michael_list_nogc.h>
9 #include <cds/container/details/make_michael_kvlist.h>
10 #include <cds/details/functor_wrapper.h>
12 namespace cds { namespace container {
17 template <typename K, typename T, class Traits>
18 struct make_michael_kvlist_nogc: public make_michael_kvlist<gc::nogc, K, T, Traits>
20 typedef make_michael_kvlist<cds::gc::nogc, K, T, Traits> base_maker;
21 typedef typename base_maker::node_type node_type;
23 struct type_traits: public base_maker::type_traits
25 typedef typename base_maker::node_deallocator disposer;
28 typedef intrusive::MichaelList<cds::gc::nogc, node_type, type_traits> type;
31 } // namespace details
34 /// Michael's ordered list (key-value pair, template specialization for gc::nogc)
35 /** @ingroup cds_nonintrusive_list
37 This specialization is intended for so-called persistent usage when no item
38 reclamation may be performed. The class does not support deleting of list item.
40 Usually, ordered single-linked list is used as a building block for the hash table implementation.
41 The complexity of searching is <tt>O(N)</tt>.
43 See \ref cds_nonintrusive_MichaelList_gc "MichaelList" for description of template parameters.
45 The interface of the specialization is a little different.
50 #ifdef CDS_DOXYGEN_INVOKED
51 typename Traits = michael_list::type_traits
56 class MichaelKVList<gc::nogc, Key, Value, Traits>:
57 #ifdef CDS_DOXYGEN_INVOKED
58 protected intrusive::MichaelList< gc::nogc, implementation_defined, Traits >
60 protected details::make_michael_kvlist_nogc< Key, Value, Traits >::type
64 typedef details::make_michael_kvlist_nogc< Key, Value, Traits > options;
65 typedef typename options::type base_class;
69 #ifdef CDS_DOXYGEN_INVOKED
70 typedef Key key_type ; ///< Key type
71 typedef Value mapped_type ; ///< Type of value stored in the list
72 typedef std::pair<key_type const, mapped_type> value_type ; ///< key/value pair stored in the list
74 typedef typename options::key_type key_type;
75 typedef typename options::value_type mapped_type;
76 typedef typename options::pair_type value_type;
79 typedef typename base_class::gc gc ; ///< Garbage collector used
80 typedef typename base_class::back_off back_off ; ///< Back-off strategy used
81 typedef typename options::allocator_type allocator_type ; ///< Allocator type used for allocate/deallocate the nodes
82 typedef typename base_class::item_counter item_counter ; ///< Item counting policy used
83 typedef typename options::key_comparator key_comparator ; ///< key comparison functor
84 typedef typename base_class::memory_model memory_model ; ///< Memory ordering. See cds::opt::memory_model option
88 typedef typename base_class::value_type node_type;
89 typedef typename options::cxx_allocator cxx_allocator;
90 typedef typename options::node_deallocator node_deallocator;
91 typedef typename options::type_traits::compare intrusive_key_comparator;
93 typedef typename base_class::atomic_node_ptr head_type;
99 static node_type * alloc_node(const K& key)
101 return cxx_allocator().New( key );
104 template <typename K, typename V>
105 static node_type * alloc_node( const K& key, const V& val )
107 return cxx_allocator().New( key, val );
110 template <typename K, typename... Args>
111 static node_type * alloc_node( K&& key, Args&&... args )
113 return cxx_allocator().MoveNew( std::forward<K>(key), std::forward<Args>(args)... );
116 static void free_node( node_type * pNode )
118 cxx_allocator().Delete( pNode );
121 struct node_disposer {
122 void operator()( node_type * pNode )
127 typedef std::unique_ptr< node_type, node_disposer > scoped_node_ptr;
131 return base_class::m_pHead;
134 head_type const& head() const
136 return base_class::m_pHead;
142 template <bool IsConst>
143 class iterator_type: protected base_class::template iterator_type<IsConst>
145 typedef typename base_class::template iterator_type<IsConst> iterator_base;
147 iterator_type( head_type const& refNode )
148 : iterator_base( refNode )
151 explicit iterator_type( const iterator_base& it )
152 : iterator_base( it )
155 friend class MichaelKVList;
158 explicit iterator_type( node_type& pNode )
159 : iterator_base( &pNode )
163 typedef typename cds::details::make_const_type<mapped_type, IsConst>::reference value_ref;
164 typedef typename cds::details::make_const_type<mapped_type, IsConst>::pointer value_ptr;
166 typedef typename cds::details::make_const_type<value_type, IsConst>::reference pair_ref;
167 typedef typename cds::details::make_const_type<value_type, IsConst>::pointer pair_ptr;
173 iterator_type( const iterator_type& src )
174 : iterator_base( src )
177 key_type const& key() const
179 typename iterator_base::value_ptr p = iterator_base::operator ->();
180 assert( p != nullptr );
181 return p->m_Data.first;
184 value_ref val() const
186 typename iterator_base::value_ptr p = iterator_base::operator ->();
187 assert( p != nullptr );
188 return p->m_Data.second;
191 pair_ptr operator ->() const
193 typename iterator_base::value_ptr p = iterator_base::operator ->();
194 return p ? &(p->m_Data) : nullptr;
197 pair_ref operator *() const
199 typename iterator_base::value_ref p = iterator_base::operator *();
204 iterator_type& operator ++()
206 iterator_base::operator ++();
211 iterator_type operator ++(int)
213 return iterator_base::operator ++(0);
217 bool operator ==(iterator_type<C> const& i ) const
219 return iterator_base::operator ==(i);
222 bool operator !=(iterator_type<C> const& i ) const
224 return iterator_base::operator !=(i);
232 The forward iterator for Michael's list based on gc::nogc has pre- and post-increment operators.
234 The iterator interface to access item data:
235 - <tt> operator -> </tt> - returns a pointer to \ref value_type for iterator
236 - <tt> operator *</tt> - returns a reference (a const reference for \p const_iterator) to \ref value_type for iterator
237 - <tt> const key_type& key() </tt> - returns a key reference for iterator
238 - <tt> mapped_type& val() </tt> - retuns a value reference for iterator (const reference for \p const_iterator)
240 For both functions the iterator should not be equal to <tt> end() </tt>
242 typedef iterator_type<false> iterator;
244 /// Const forward iterator
246 For iterator's features and requirements see \ref iterator
248 typedef iterator_type<true> const_iterator;
250 /// Returns a forward iterator addressing the first element in a list
252 For empty list \code begin() == end() \endcode
256 return iterator( head() );
259 /// Returns an iterator that addresses the location succeeding the last element in a list
261 Do not use the value returned by <tt>end</tt> function to access any item.
262 Internally, <tt>end</tt> returning value equals to \p nullptr.
264 The returned value can be used only to control reaching the end of the list.
265 For empty list \code begin() == end() \endcode
272 /// Returns a forward const iterator addressing the first element in a list
274 const_iterator begin() const
276 return const_iterator( head() );
278 const_iterator cbegin()
280 return const_iterator( head() );
284 /// Returns an const iterator that addresses the location succeeding the last element in a list
286 const_iterator end() const
288 return const_iterator();
290 const_iterator cend()
292 return const_iterator();
298 iterator node_to_iterator( node_type * pNode )
301 return iterator( *pNode );
307 /// Default constructor
309 Initialize empty list
323 /// Inserts new node with key and default value
325 The function creates a node with \p key and default value, and then inserts the node created into the list.
328 - The \ref key_type should be constructible from value of type \p K.
329 In trivial case, \p K is equal to \ref key_type.
330 - The \ref mapped_type should be default-constructible.
332 Returns an iterator pointed to inserted value, or \p end() if inserting is failed
334 template <typename K>
335 iterator insert( const K& key )
337 return node_to_iterator( insert_at( head(), key ));
340 /// Inserts new node with a key and a value
342 The function creates a node with \p key and value \p val, and then inserts the node created into the list.
345 - The \ref key_type should be constructible from \p key of type \p K.
346 - The \ref mapped_type should be constructible from \p val of type \p V.
348 Returns an iterator pointed to inserted value, or \p end() if inserting is failed
350 template <typename K, typename V>
351 iterator insert( const K& key, const V& val )
353 // We cannot use insert with functor here
354 // because we cannot lock inserted node for updating
355 // Therefore, we use separate function
356 return node_to_iterator( insert_at( head(), key, val ));
359 /// Inserts new node and initialize it by a functor
361 This function inserts new node with key \p key and if inserting is successful then it calls
362 \p func functor with signature
363 \code void func( value_type& item );
365 void operator()( value_type& item );
369 The argument \p item of user-defined functor \p func is the reference
370 to the list's item inserted. <tt>item.second</tt> is a reference to item's value that may be changed.
371 User-defined functor \p func should guarantee that during changing item's value no any other changes
372 could be made on this list's item by concurrent threads.
373 The user-defined functor can be passed by reference using \p std::ref
374 and it is called only if the inserting is successful.
376 The key_type should be constructible from value of type \p K.
378 The function allows to split creating of new item into two part:
379 - create item from \p key;
380 - insert new item into the list;
381 - if inserting is successful, initialize the value of item by calling \p f functor
383 This can be useful if complete initialization of object of \p mapped_type is heavyweight and
384 it is preferable that the initialization should be completed only if inserting is successful.
386 Returns an iterator pointed to inserted value, or \p end() if inserting is failed
388 template <typename K, typename Func>
389 iterator insert_key( const K& key, Func func )
391 return node_to_iterator( insert_key_at( head(), key, func ));
394 /// Ensures that the key \p key exists in the list
396 The operation inserts new item if the key \p key is not found in the list.
397 Otherwise, the function returns an iterator that points to item found.
399 Returns <tt> std::pair<iterator, bool> </tt> where \p first is an iterator pointing to
400 item found or inserted, \p second is true if new item has been added or \p false if the item
401 already is in the list.
403 template <typename K>
404 std::pair<iterator, bool> ensure( const K& key )
406 std::pair< node_type *, bool > ret = ensure_at( head(), key );
407 return std::make_pair( node_to_iterator( ret.first ), ret.second );
410 /// Inserts data of type \ref mapped_type constructed with <tt>std::forward<Args>(args)...</tt>
412 Returns an iterator pointed to inserted value, or \p end() if inserting is failed
414 template <typename K, typename... Args>
415 iterator emplace( K&& key, Args&&... args )
417 return node_to_iterator( emplace_at( head(), std::forward<K>(key), std::forward<Args>(args)... ));
420 /// Find the key \p key
421 /** \anchor cds_nonintrusive_MichaelKVList_nogc_find
423 The function searches the item with key equal to \p key
424 and returns an iterator pointed to item found if the key is found,
425 and \ref end() otherwise
427 template <typename Q>
428 iterator find( Q const& key )
430 return node_to_iterator( find_at( head(), key, intrusive_key_comparator() ) );
433 /// Finds the key \p val using \p pred predicate for searching
435 The function is an analog of \ref cds_nonintrusive_MichaelKVList_nogc_find "find(Q const&)"
436 but \p pred is used for key comparing.
437 \p Less functor has the interface like \p std::less.
438 \p pred must imply the same element order as the comparator used for building the list.
440 template <typename Q, typename Less>
441 iterator find_with( Q const& key, Less pred )
443 return node_to_iterator( find_at( head(), key, typename options::template less_wrapper<Less>::type() ) );
446 /// Check if the list is empty
449 return base_class::empty();
452 /// Returns list's item count
454 The value returned depends on opt::item_counter option. For atomicity::empty_item_counter,
455 this function always returns 0.
457 <b>Warning</b>: even if you use real item counter and it returns 0, this fact is not mean that the list
458 is empty. To check list emptyness use \ref empty() method.
462 return base_class::size();
467 Post-condition: the list is empty
476 node_type * insert_node_at( head_type& refHead, node_type * pNode )
478 assert( pNode != nullptr );
479 scoped_node_ptr p( pNode );
480 if ( base_class::insert_at( refHead, *pNode ))
485 template <typename K>
486 node_type * insert_at( head_type& refHead, const K& key )
488 return insert_node_at( refHead, alloc_node( key ));
491 template <typename K, typename V>
492 node_type * insert_at( head_type& refHead, const K& key, const V& val )
494 return insert_node_at( refHead, alloc_node( key, val ));
497 template <typename K, typename Func>
498 node_type * insert_key_at( head_type& refHead, const K& key, Func f )
500 scoped_node_ptr pNode( alloc_node( key ));
502 if ( base_class::insert_at( refHead, *pNode )) {
504 return pNode.release();
509 template <typename K>
510 std::pair< node_type *, bool > ensure_at( head_type& refHead, const K& key )
512 scoped_node_ptr pNode( alloc_node( key ));
513 node_type * pItemFound = nullptr;
515 std::pair<bool, bool> ret = base_class::ensure_at( refHead, *pNode, [&pItemFound](bool, node_type& item, node_type&){ pItemFound = &item; });
516 assert( pItemFound != nullptr );
518 if ( ret.first && ret.second )
520 return std::make_pair( pItemFound, ret.second );
523 template <typename K, typename... Args>
524 node_type * emplace_at( head_type& refHead, K&& key, Args&&... args )
526 return insert_node_at( refHead, alloc_node( std::forward<K>(key), std::forward<Args>(args)... ));
529 template <typename K, typename Compare>
530 node_type * find_at( head_type& refHead, K const& key, Compare cmp )
532 return base_class::find_at( refHead, key, cmp );
536 template <typename K, typename Compare typename Func>
537 bool find_at( head_type& refHead, K& key, Compare cmp, Func f )
539 return base_class::find_at( refHead, key, cmp, [&f]( node_type& node, K const& ){ f( node.m_Data ); });
545 }} // namespace cds::container
547 #endif // #ifndef __CDS_CONTAINER_MICHAEL_KVLIST_NOGC_H