3 #ifndef __CDS_CONTAINER_MICHAEL_KVLIST_NOGC_H
4 #define __CDS_CONTAINER_MICHAEL_KVLIST_NOGC_H
7 #include <cds/container/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;
98 # ifndef CDS_CXX11_LAMBDA_SUPPORT
101 node_type * m_pItemFound;
104 : m_pItemFound( nullptr )
107 void operator ()(bool, node_type& item, node_type& )
109 m_pItemFound = &item;
113 template <typename Func>
114 class find_functor: protected cds::details::functor_wrapper<Func>
116 typedef cds::details::functor_wrapper<Func> base_class;
118 find_functor( Func f )
122 template <typename Q>
123 void operator ()( node_type& node, Q& )
125 base_class::get()( node.m_Data );
133 template <typename K>
134 static node_type * alloc_node(const K& key)
136 return cxx_allocator().New( key );
139 template <typename K, typename V>
140 static node_type * alloc_node( const K& key, const V& val )
142 return cxx_allocator().New( key, val );
145 #ifdef CDS_EMPLACE_SUPPORT
146 template <typename K, typename... Args>
147 static node_type * alloc_node( K&& key, Args&&... args )
149 return cxx_allocator().MoveNew( std::forward<K>(key), std::forward<Args>(args)... );
153 static void free_node( node_type * pNode )
155 cxx_allocator().Delete( pNode );
158 struct node_disposer {
159 void operator()( node_type * pNode )
164 typedef std::unique_ptr< node_type, node_disposer > scoped_node_ptr;
168 return base_class::m_pHead;
171 head_type const& head() const
173 return base_class::m_pHead;
179 template <bool IsConst>
180 class iterator_type: protected base_class::template iterator_type<IsConst>
182 typedef typename base_class::template iterator_type<IsConst> iterator_base;
184 iterator_type( head_type const& refNode )
185 : iterator_base( refNode )
188 explicit iterator_type( const iterator_base& it )
189 : iterator_base( it )
192 friend class MichaelKVList;
195 explicit iterator_type( node_type& pNode )
196 : iterator_base( &pNode )
200 typedef typename cds::details::make_const_type<mapped_type, IsConst>::reference value_ref;
201 typedef typename cds::details::make_const_type<mapped_type, IsConst>::pointer value_ptr;
203 typedef typename cds::details::make_const_type<value_type, IsConst>::reference pair_ref;
204 typedef typename cds::details::make_const_type<value_type, IsConst>::pointer pair_ptr;
210 iterator_type( const iterator_type& src )
211 : iterator_base( src )
214 key_type const& key() const
216 typename iterator_base::value_ptr p = iterator_base::operator ->();
217 assert( p != nullptr );
218 return p->m_Data.first;
221 value_ref val() const
223 typename iterator_base::value_ptr p = iterator_base::operator ->();
224 assert( p != nullptr );
225 return p->m_Data.second;
228 pair_ptr operator ->() const
230 typename iterator_base::value_ptr p = iterator_base::operator ->();
231 return p ? &(p->m_Data) : nullptr;
234 pair_ref operator *() const
236 typename iterator_base::value_ref p = iterator_base::operator *();
241 iterator_type& operator ++()
243 iterator_base::operator ++();
248 iterator_type operator ++(int)
250 return iterator_base::operator ++(0);
254 bool operator ==(iterator_type<C> const& i ) const
256 return iterator_base::operator ==(i);
259 bool operator !=(iterator_type<C> const& i ) const
261 return iterator_base::operator !=(i);
269 The forward iterator for Michael's list based on gc::nogc has pre- and post-increment operators.
271 The iterator interface to access item data:
272 - <tt> operator -> </tt> - returns a pointer to \ref value_type for iterator
273 - <tt> operator *</tt> - returns a reference (a const reference for \p const_iterator) to \ref value_type for iterator
274 - <tt> const key_type& key() </tt> - returns a key reference for iterator
275 - <tt> mapped_type& val() </tt> - retuns a value reference for iterator (const reference for \p const_iterator)
277 For both functions the iterator should not be equal to <tt> end() </tt>
279 typedef iterator_type<false> iterator;
281 /// Const forward iterator
283 For iterator's features and requirements see \ref iterator
285 typedef iterator_type<true> const_iterator;
287 /// Returns a forward iterator addressing the first element in a list
289 For empty list \code begin() == end() \endcode
293 return iterator( head() );
296 /// Returns an iterator that addresses the location succeeding the last element in a list
298 Do not use the value returned by <tt>end</tt> function to access any item.
299 Internally, <tt>end</tt> returning value equals to <tt>NULL</tt>.
301 The returned value can be used only to control reaching the end of the list.
302 For empty list \code begin() == end() \endcode
309 /// Returns a forward const iterator addressing the first element in a list
311 const_iterator begin() const
313 return const_iterator( head() );
315 const_iterator cbegin()
317 return const_iterator( head() );
321 /// Returns an const iterator that addresses the location succeeding the last element in a list
323 const_iterator end() const
325 return const_iterator();
327 const_iterator cend()
329 return const_iterator();
335 iterator node_to_iterator( node_type * pNode )
338 return iterator( *pNode );
344 /// Default constructor
346 Initialize empty list
360 /// Inserts new node with key and default value
362 The function creates a node with \p key and default value, and then inserts the node created into the list.
365 - The \ref key_type should be constructible from value of type \p K.
366 In trivial case, \p K is equal to \ref key_type.
367 - The \ref mapped_type should be default-constructible.
369 Returns an iterator pointed to inserted value, or \p end() if inserting is failed
371 template <typename K>
372 iterator insert( const K& key )
374 return node_to_iterator( insert_at( head(), key ));
377 /// Inserts new node with a key and a value
379 The function creates a node with \p key and value \p val, and then inserts the node created into the list.
382 - The \ref key_type should be constructible from \p key of type \p K.
383 - The \ref mapped_type should be constructible from \p val of type \p V.
385 Returns an iterator pointed to inserted value, or \p end() if inserting is failed
387 template <typename K, typename V>
388 iterator insert( const K& key, const V& val )
390 // We cannot use insert with functor here
391 // because we cannot lock inserted node for updating
392 // Therefore, we use separate function
393 return node_to_iterator( insert_at( head(), key, val ));
396 /// Inserts new node and initialize it by a functor
398 This function inserts new node with key \p key and if inserting is successful then it calls
399 \p func functor with signature
400 \code void func( value_type& item );
402 void operator()( value_type& item );
406 The argument \p item of user-defined functor \p func is the reference
407 to the list's item inserted. <tt>item.second</tt> is a reference to item's value that may be changed.
408 User-defined functor \p func should guarantee that during changing item's value no any other changes
409 could be made on this list's item by concurrent threads.
410 The user-defined functor can be passed by reference using <tt>boost::ref</tt>
411 and it is called only if the inserting is successful.
413 The key_type should be constructible from value of type \p K.
415 The function allows to split creating of new item into two part:
416 - create item from \p key;
417 - insert new item into the list;
418 - if inserting is successful, initialize the value of item by calling \p f functor
420 This can be useful if complete initialization of object of \p mapped_type is heavyweight and
421 it is preferable that the initialization should be completed only if inserting is successful.
423 Returns an iterator pointed to inserted value, or \p end() if inserting is failed
425 template <typename K, typename Func>
426 iterator insert_key( const K& key, Func func )
428 return node_to_iterator( insert_key_at( head(), key, func ));
431 /// Ensures that the key \p key exists in the list
433 The operation inserts new item if the key \p key is not found in the list.
434 Otherwise, the function returns an iterator that points to item found.
436 Returns <tt> std::pair<iterator, bool> </tt> where \p first is an iterator pointing to
437 item found or inserted, \p second is true if new item has been added or \p false if the item
438 already is in the list.
440 template <typename K>
441 std::pair<iterator, bool> ensure( const K& key )
443 std::pair< node_type *, bool > ret = ensure_at( head(), key );
444 return std::make_pair( node_to_iterator( ret.first ), ret.second );
447 # ifdef CDS_EMPLACE_SUPPORT
448 /// Inserts data of type \ref mapped_type constructed with <tt>std::forward<Args>(args)...</tt>
450 Returns an iterator pointed to inserted value, or \p end() if inserting is failed
452 This function is available only for compiler that supports
453 variadic template and move semantics
455 template <typename K, typename... Args>
456 iterator emplace( K&& key, Args&&... args )
458 return node_to_iterator( emplace_at( head(), std::forward<K>(key), std::forward<Args>(args)... ));
462 /// Find the key \p key
463 /** \anchor cds_nonintrusive_MichaelKVList_nogc_find
465 The function searches the item with key equal to \p key
466 and returns an iterator pointed to item found if the key is found,
467 and \ref end() otherwise
469 template <typename Q>
470 iterator find( Q const& key )
472 return node_to_iterator( find_at( head(), key, intrusive_key_comparator() ) );
475 /// Finds the key \p val using \p pred predicate for searching
477 The function is an analog of \ref cds_nonintrusive_MichaelKVList_nogc_find "find(Q const&)"
478 but \p pred is used for key comparing.
479 \p Less functor has the interface like \p std::less.
480 \p pred must imply the same element order as the comparator used for building the list.
482 template <typename Q, typename Less>
483 iterator find_with( Q const& key, Less pred )
485 return node_to_iterator( find_at( head(), key, typename options::template less_wrapper<Less>::type() ) );
488 /// Check if the list is empty
491 return base_class::empty();
494 /// Returns list's item count
496 The value returned depends on opt::item_counter option. For atomicity::empty_item_counter,
497 this function always returns 0.
499 <b>Warning</b>: even if you use real item counter and it returns 0, this fact is not mean that the list
500 is empty. To check list emptyness use \ref empty() method.
504 return base_class::size();
509 Post-condition: the list is empty
518 node_type * insert_node_at( head_type& refHead, node_type * pNode )
520 assert( pNode != nullptr );
521 scoped_node_ptr p( pNode );
522 if ( base_class::insert_at( refHead, *pNode ))
527 template <typename K>
528 node_type * insert_at( head_type& refHead, const K& key )
530 return insert_node_at( refHead, alloc_node( key ));
533 template <typename K, typename V>
534 node_type * insert_at( head_type& refHead, const K& key, const V& val )
536 return insert_node_at( refHead, alloc_node( key, val ));
539 template <typename K, typename Func>
540 node_type * insert_key_at( head_type& refHead, const K& key, Func f )
542 scoped_node_ptr pNode( alloc_node( key ));
544 if ( base_class::insert_at( refHead, *pNode )) {
545 cds::unref(f)( pNode->m_Data );
546 return pNode.release();
551 template <typename K>
552 std::pair< node_type *, bool > ensure_at( head_type& refHead, const K& key )
554 scoped_node_ptr pNode( alloc_node( key ));
555 node_type * pItemFound = nullptr;
557 # ifdef CDS_CXX11_LAMBDA_SUPPORT
558 std::pair<bool, bool> ret = base_class::ensure_at( refHead, *pNode, [&pItemFound](bool, node_type& item, node_type&){ pItemFound = &item; });
561 std::pair<bool, bool> ret = base_class::ensure_at( refHead, *pNode, boost::ref(func) );
562 pItemFound = func.m_pItemFound;
564 assert( pItemFound != nullptr );
566 if ( ret.first && ret.second )
568 return std::make_pair( pItemFound, ret.second );
571 # ifdef CDS_EMPLACE_SUPPORT
572 template <typename K, typename... Args>
573 node_type * emplace_at( head_type& refHead, K&& key, Args&&... args )
575 return insert_node_at( refHead, alloc_node( std::forward<K>(key), std::forward<Args>(args)... ));
579 template <typename K, typename Compare>
580 node_type * find_at( head_type& refHead, K const& key, Compare cmp )
582 return base_class::find_at( refHead, key, cmp );
586 template <typename K, typename Compare typename Func>
587 bool find_at( head_type& refHead, K& key, Compare cmp, Func f )
589 # ifdef CDS_CXX11_LAMBDA_SUPPORT
590 return base_class::find_at( refHead, key, cmp, [&f]( node_type& node, K const& ){ cds::unref(f)( node.m_Data ); });
592 find_functor<Func> wrapper( f );
593 return base_class::find_at( refHead, key, cmp, cds::ref(wrapper) );
600 }} // namespace cds::container
602 #endif // #ifndef __CDS_CONTAINER_MICHAEL_KVLIST_NOGC_H