3 #ifndef __CDS_CONTAINER_LAZY_KVLIST_NOGC_H
4 #define __CDS_CONTAINER_LAZY_KVLIST_NOGC_H
7 #include <cds/container/lazy_list_base.h>
8 #include <cds/intrusive/lazy_list_nogc.h>
9 #include <cds/container/details/make_lazy_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_lazy_kvlist_nogc: public make_lazy_kvlist<gc::nogc, K, T, Traits>
20 typedef make_lazy_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::LazyList<cds::gc::nogc, node_type, type_traits> type;
31 } // namespace details
34 /// Lazy 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_LazyList_gc "LazyList" for description of template parameters.
45 The interface of the specialization is a little different.
50 #ifdef CDS_DOXYGEN_INVOKED
51 typename Traits = lazy_list::type_traits
56 class LazyKVList<gc::nogc, Key, Value, Traits>:
57 #ifdef CDS_DOXYGEN_INVOKED
58 protected intrusive::LazyList< gc::nogc, implementation_defined, Traits >
60 protected details::make_lazy_kvlist_nogc< Key, Value, Traits >::type
64 typedef details::make_lazy_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;
78 typedef typename base_class::gc gc ; ///< Garbage collector used
79 typedef typename base_class::back_off back_off ; ///< Back-off strategy used
80 typedef typename options::allocator_type allocator_type ; ///< Allocator type used for allocate/deallocate the nodes
81 typedef typename base_class::item_counter item_counter ; ///< Item counting policy used
82 typedef typename options::key_comparator key_comparator ; ///< key comparison functor
83 typedef typename base_class::memory_model memory_model ; ///< Memory ordering. See cds::opt::memory_model option
87 typedef typename base_class::value_type node_type;
88 typedef typename options::cxx_allocator cxx_allocator;
89 typedef typename options::node_deallocator node_deallocator;
90 typedef typename options::type_traits::compare intrusive_key_comparator;
92 typedef typename base_class::node_type head_type;
98 static node_type * alloc_node(const K& key)
100 return cxx_allocator().New( key );
103 template <typename K, typename V>
104 static node_type * alloc_node( const K& key, const V& val )
106 return cxx_allocator().New( key, val );
109 template <typename... Args>
110 static node_type * alloc_node( Args&&... args )
112 return cxx_allocator().MoveNew( std::forward<Args>(args)... );
115 static void free_node( node_type * pNode )
117 cxx_allocator().Delete( pNode );
120 struct node_disposer {
121 void operator()( node_type * pNode )
126 typedef std::unique_ptr< node_type, node_disposer > scoped_node_ptr;
130 return base_class::m_Head;
133 head_type const& head() const
135 return base_class::m_Head;
140 return base_class::m_Tail;
143 head_type const& tail() const
145 return base_class::m_Tail;
151 template <bool IsConst>
152 class iterator_type: protected base_class::template iterator_type<IsConst>
154 typedef typename base_class::template iterator_type<IsConst> iterator_base;
156 iterator_type( head_type const& refNode )
157 : iterator_base( const_cast<head_type *>( &refNode ))
160 explicit iterator_type( const iterator_base& it )
161 : iterator_base( it )
164 friend class LazyKVList;
167 explicit iterator_type( node_type& pNode )
168 : iterator_base( &pNode )
172 typedef typename cds::details::make_const_type<mapped_type, IsConst>::reference value_ref;
173 typedef typename cds::details::make_const_type<mapped_type, IsConst>::pointer value_ptr;
175 typedef typename cds::details::make_const_type<value_type, IsConst>::reference pair_ref;
176 typedef typename cds::details::make_const_type<value_type, IsConst>::pointer pair_ptr;
182 iterator_type( const iterator_type& src )
183 : iterator_base( src )
186 key_type const& key() const
188 typename iterator_base::value_ptr p = iterator_base::operator ->();
189 assert( p != nullptr );
190 return p->m_Data.first;
193 value_ref val() const
195 typename iterator_base::value_ptr p = iterator_base::operator ->();
196 assert( p != nullptr );
197 return p->m_Data.second;
200 pair_ptr operator ->() const
202 typename iterator_base::value_ptr p = iterator_base::operator ->();
203 return p ? &(p->m_Data) : nullptr;
206 pair_ref operator *() const
208 typename iterator_base::value_ref p = iterator_base::operator *();
213 iterator_type& operator ++()
215 iterator_base::operator ++();
220 iterator_type operator ++(int)
222 return iterator_base::operator ++(0);
226 bool operator ==(iterator_type<C> const& i ) const
228 return iterator_base::operator ==(i);
231 bool operator !=(iterator_type<C> const& i ) const
233 return iterator_base::operator !=(i);
241 The forward iterator for lazy list based on gc::nogc has pre- and post-increment operators.
243 The iterator interface to access item data:
244 - <tt> operator -> </tt> - returns a pointer to \ref value_type for iterator
245 - <tt> operator *</tt> - returns a reference (a const reference for \p const_iterator) to \ref value_type for iterator
246 - <tt> const key_type& key() </tt> - returns a key reference for iterator
247 - <tt> mapped_type& val() </tt> - retuns a value reference for iterator (const reference for \p const_iterator)
249 For both functions the iterator should not be equal to <tt> end() </tt>
251 typedef iterator_type<false> iterator;
253 /// Const forward iterator
255 For iterator's features and requirements see \ref iterator
257 typedef iterator_type<true> const_iterator;
259 /// Returns a forward iterator addressing the first element in a list
261 For empty list \code begin() == end() \endcode
265 iterator it( head() );
266 ++it ; // skip dummy head
270 /// Returns an iterator that addresses the location succeeding the last element in a list
272 Do not use the value returned by <tt>end</tt> function to access any item.
273 Internally, <tt>end</tt> returning value equals to nullptr.
275 The returned value can be used only to control reaching the end of the list.
276 For empty list \code begin() == end() \endcode
280 return iterator( tail());
283 /// Returns a forward const iterator addressing the first element in a list
285 const_iterator begin() const
287 const_iterator it( head() );
288 ++it ; // skip dummy head
291 const_iterator cbegin()
293 const_iterator it( head() );
294 ++it ; // skip dummy head
299 /// Returns an const iterator that addresses the location succeeding the last element in a list
301 const_iterator end() const
303 return const_iterator( tail());
305 const_iterator cend()
307 return const_iterator( tail());
313 iterator node_to_iterator( node_type * pNode )
316 return iterator( *pNode );
322 /// Default constructor
324 Initialize empty list
338 /// Inserts new node with key and default value
340 The function creates a node with \p key and default value, and then inserts the node created into the list.
343 - The \ref key_type should be constructible from value of type \p K.
344 In trivial case, \p K is equal to \ref key_type.
345 - The \ref mapped_type should be default-constructible.
347 Returns an iterator pointed to inserted value, or \p end() if inserting is failed
349 template <typename K>
350 iterator insert( const K& key )
352 return node_to_iterator( insert_at( head(), key ));
355 /// Inserts new node with a key and a value
357 The function creates a node with \p key and value \p val, and then inserts the node created into the list.
360 - The \ref key_type should be constructible from \p key of type \p K.
361 - The \ref mapped_type should be constructible from \p val of type \p V.
363 Returns an iterator pointed to inserted value, or \p end() if inserting is failed
365 template <typename K, typename V>
366 iterator insert( const K& key, const V& val )
368 // We cannot use insert with functor here
369 // because we cannot lock inserted node for updating
370 // Therefore, we use separate function
371 return node_to_iterator( insert_at( head(), key, val ));
374 /// Inserts new node and initialize it by a functor
376 This function inserts new node with key \p key and if inserting is successful then it calls
377 \p func functor with signature
378 \code void func( value_type& item ) ; endcode
382 void operator()( value_type& item );
386 The argument \p item of user-defined functor \p func is the reference
387 to the list's item inserted. <tt>item.second</tt> is a reference to item's value that may be changed.
388 User-defined functor \p func should guarantee that during changing item's value no any other changes
389 could be made on this list's item by concurrent threads.
390 The user-defined functor can be passed by reference using <tt>boost::ref</tt>
391 and it is called only if the inserting is successful.
393 The key_type should be constructible from value of type \p K.
395 The function allows to split creating of new item into two part:
396 - create item from \p key;
397 - insert new item into the list;
398 - if inserting is successful, initialize the value of item by calling \p f functor
400 This can be useful if complete initialization of object of \p mapped_type is heavyweight and
401 it is preferable that the initialization should be completed only if inserting is successful.
403 Returns an iterator pointed to inserted value, or \p end() if inserting is failed
405 template <typename K, typename Func>
406 iterator insert_key( const K& key, Func func )
408 return node_to_iterator( insert_key_at( head(), key, func ));
411 /// Ensures that the key \p key exists in the list
413 The operation inserts new item if the key \p key is not found in the list.
414 Otherwise, the function returns an iterator that points to item found.
416 Returns <tt> std::pair<iterator, bool> </tt> where \p first is an iterator pointing to
417 item found or inserted, \p second is true if new item has been added or \p false if the item
418 already is in the list.
420 template <typename K>
421 std::pair<iterator, bool> ensure( const K& key )
423 std::pair< node_type *, bool > ret = ensure_at( head(), key );
424 return std::make_pair( node_to_iterator( ret.first ), ret.second );
427 /// Inserts data of type \ref mapped_type constructed with <tt>std::forward<Args>(args)...</tt>
429 Returns an iterator pointed to inserted value, or \p end() if inserting is failed
431 template <typename... Args>
432 iterator emplace( Args&&... args )
434 return node_to_iterator( emplace_at( head(), std::forward<Args>(args)... ));
437 /// Find the key \p key
438 /** \anchor cds_nonintrusive_LazyKVList_nogc_find
439 The function searches the item with key equal to \p key
440 and returns an iterator pointed to item found if the key is found,
441 and \ref end() otherwise
443 template <typename Q>
444 iterator find( Q const& key )
446 return node_to_iterator( find_at( head(), key, intrusive_key_comparator() ) );
449 /// Finds the key \p val using \p pred predicate for searching
451 The function is an analog of \ref cds_nonintrusive_LazyKVList_nogc_find "find(Q const&)"
452 but \p pred is used for key comparing.
453 \p Less functor has the interface like \p std::less.
454 \p pred must imply the same element order as the comparator used for building the list.
456 template <typename Q, typename Less>
457 iterator find_with( Q const& key, Less pred )
459 return node_to_iterator( find_at( head(), key, typename options::template less_wrapper<Less>::type() ) );
462 /// Check if the list is empty
465 return base_class::empty();
468 /// Returns list's item count
470 The value returned depends on opt::item_counter option. For atomicity::empty_item_counter,
471 this function always returns 0.
473 <b>Warning</b>: even if you use real item counter and it returns 0, this fact is not mean that the list
474 is empty. To check list emptyness use \ref empty() method.
478 return base_class::size();
483 Post-condition: the list is empty
492 node_type * insert_node_at( head_type& refHead, node_type * pNode )
494 assert( pNode != nullptr );
495 scoped_node_ptr p( pNode );
496 if ( base_class::insert_at( &refHead, *p ))
502 template <typename K>
503 node_type * insert_at( head_type& refHead, const K& key )
505 return insert_node_at( refHead, alloc_node( key ));
508 template <typename K, typename V>
509 node_type * insert_at( head_type& refHead, const K& key, const V& val )
511 return insert_node_at( refHead, alloc_node( key, val ));
514 template <typename K, typename Func>
515 node_type * insert_key_at( head_type& refHead, const K& key, Func f )
517 scoped_node_ptr pNode( alloc_node( key ));
519 if ( base_class::insert_at( &refHead, *pNode )) {
520 cds::unref(f)( pNode->m_Data );
521 return pNode.release();
528 template <typename K>
529 std::pair< node_type *, bool > ensure_at( head_type& refHead, const K& key )
531 scoped_node_ptr pNode( alloc_node( key ));
532 node_type * pItemFound = nullptr;
534 std::pair<bool, bool> ret = base_class::ensure_at( &refHead, *pNode, [&pItemFound](bool, node_type& item, node_type&){ pItemFound = &item; } );
535 if ( ret.first && ret.second )
538 assert( pItemFound != nullptr );
539 return std::make_pair( pItemFound, ret.second );
542 template <typename... Args>
543 node_type * emplace_at( head_type& refHead, Args&&... args )
545 return insert_node_at( refHead, alloc_node( std::forward<Args>(args)... ));
548 template <typename K, typename Compare>
549 node_type * find_at( head_type& refHead, const K& key, Compare cmp )
551 return base_class::find_at( &refHead, key, cmp );
555 template <typename K, typenam Compare, typename Func>
556 bool find_at( head_type& refHead, K& key, Compare cmp, Func f )
558 return base_class::find_at( &refHead, key, cmp, [&f]( node_type& node, K const& ){ cds::unref(f)( node.m_Data ); });
564 }} // namespace cds::container
566 #endif // #ifndef __CDS_CONTAINER_LAZY_KVLIST_NOGC_H