--- /dev/null
+/*
+ This file is a part of libcds - Concurrent Data Structures library
+
+ (C) Copyright Maxim Khizhinsky (libcds.dev@gmail.com) 2006-2017
+
+ Source code repo: http://github.com/khizmax/libcds/
+ Download: http://sourceforge.net/projects/libcds/files/
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright notice, this
+ list of conditions and the following disclaimer.
+
+ * Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions and the following disclaimer in the documentation
+ and/or other materials provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#ifndef CDSLIB_CONTAINER_MICHAEL_LIST_RCU_H
+#define CDSLIB_CONTAINER_MICHAEL_LIST_RCU_H
+
+#include <memory>
+#include <cds/container/details/michael_list_base.h>
+#include <cds/intrusive/michael_list_rcu.h>
+#include <cds/container/details/make_michael_list.h>
+#include <cds/details/binary_functor_wrapper.h>
+
+namespace cds { namespace container {
+
+ /// Michael's ordered list (template specialization for \ref cds_urcu_desc "RCU")
+ /** @ingroup cds_nonintrusive_list
+ \anchor cds_nonintrusive_MichaelList_rcu
+
+ Usually, ordered single-linked list is used as a building block for the hash table implementation.
+ The complexity of searching is <tt>O(N)</tt>.
+
+ Source:
+ - [2002] Maged Michael "High performance dynamic lock-free hash tables and list-based sets"
+
+ This class is non-intrusive version of \ref cds_intrusive_MichaelList_rcu "cds::intrusive::MichaelList" RCU specialization.
+
+ Template arguments:
+ - \p RCU - one of \ref cds_urcu_gc "RCU type"
+ - \p T - type stored in the list. The type must be default- and copy-constructible.
+ - \p Traits - type traits, default is michael_list::traits
+
+ The implementation does not divide type \p T into key and value part and
+ may be used as a main building block for hash set containers.
+ The key is a function (or a part) of type \p T, and this function is specified by <tt>Traits::compare</tt> functor
+ or <tt>Traits::less</tt> predicate.
+
+ \ref cds_nonintrusive_MichaelKVList_rcu "MichaelKVList" is a key-value version of Michael's
+ non-intrusive list that is closer to the C++ std library approach.
+
+ @note Before including <tt><cds/container/michael_list_rcu.h></tt> you should include appropriate RCU header file,
+ see \ref cds_urcu_gc "RCU type" for list of existing RCU class and corresponding header files.
+
+ It is possible to declare option-based list with cds::container::michael_list::make_traits metafunction istead of \p Traits template
+ argument. For example, the following traits-based declaration of Michael's list
+
+ \code
+ #include <cds/urcu/general_buffered.h>
+ #include <cds/container/michael_list_rcu.h>
+ // Declare comparator for the item
+ struct my_compare {
+ int operator ()( int i1, int i2 )
+ {
+ return i1 - i2;
+ }
+ };
+
+ // Declare traits
+ struct my_traits: public cds::container::michael_list::traits
+ {
+ typedef my_compare compare;
+ };
+
+ // Declare traits-based list
+ typedef cds::container::MichaelList< cds::urcu::gc< cds::urcu::general_buffered<> >, int, my_traits > traits_based_list;
+ \endcode
+
+ is equivalent for the following option-based list
+ \code
+ #include <cds/urcu/general_buffered.h>
+ #include <cds/container/michael_list_rcu.h>
+
+ // my_compare is the same
+
+ // Declare option-based list
+ typedef cds::container::MichaelList< cds::urcu::gc< cds::urcu::general_buffered<> >, int,
+ typename cds::container::michael_list::make_traits<
+ cds::container::opt::compare< my_compare > // item comparator option
+ >::type
+ > option_based_list;
+ \endcode
+
+ Template argument list \p Options of cds::container::michael_list::make_traits metafunction are:
+ - opt::compare - key comparison functor. No default functor is provided.
+ If the option is not specified, the opt::less is used.
+ - opt::less - specifies binary predicate used for key comparison. Default is \p std::less<T>.
+ - opt::back_off - back-off strategy used. If the option is not specified, the cds::backoff::empty is used.
+ - opt::item_counter - the type of item counting feature. Default is \ref atomicity::empty_item_counter that is no item counting.
+ - opt::allocator - the allocator used for creating and freeing list's item. Default is \ref CDS_DEFAULT_ALLOCATOR macro.
+ - opt::memory_model - C++ memory ordering model. Can be opt::v::relaxed_ordering (relaxed memory model, the default)
+ or opt::v::sequential_consistent (sequentially consisnent memory model).
+ - opt::rcu_check_deadlock - a deadlock checking policy. Default is opt::v::rcu_throw_deadlock
+ */
+ template <
+ typename RCU,
+ typename T,
+#ifdef CDS_DOXYGEN_INVOKED
+ typename Traits = michael_list::traits
+#else
+ typename Traits
+#endif
+ >
+ class MichaelList< cds::urcu::gc<RCU>, T, Traits > :
+#ifdef CDS_DOXYGEN_INVOKED
+ protected intrusive::MichaelList< cds::urcu::gc<RCU>, T, Traits >
+#else
+ protected details::make_michael_list< cds::urcu::gc<RCU>, T, Traits >::type
+#endif
+ {
+ //@cond
+ typedef details::make_michael_list< cds::urcu::gc<RCU>, T, Traits > maker;
+ typedef typename maker::type base_class;
+ //@endcond
+
+ public:
+ typedef cds::urcu::gc<RCU> gc; ///< RCU
+ typedef T value_type; ///< Type of value stored in the list
+ typedef Traits traits; ///< List traits
+
+ typedef typename base_class::back_off back_off; ///< Back-off strategy used
+ typedef typename maker::allocator_type allocator_type; ///< Allocator type used for allocate/deallocate the nodes
+ typedef typename base_class::item_counter item_counter; ///< Item counting policy used
+ typedef typename maker::key_comparator key_comparator; ///< key comparison functor
+ typedef typename base_class::memory_model memory_model; ///< Memory ordering. See cds::opt::memory_model option
+ typedef typename base_class::stat stat; ///< Internal statistics
+ typedef typename base_class::rcu_check_deadlock rcu_check_deadlock ; ///< RCU deadlock checking policy
+
+ typedef typename gc::scoped_lock rcu_lock ; ///< RCU scoped lock
+ static constexpr const bool c_bExtractLockExternal = base_class::c_bExtractLockExternal; ///< Group of \p extract_xxx functions do not require external locking
+
+ //@cond
+ // Rebind traits (split-list support)
+ template <typename... Options>
+ struct rebind_traits {
+ typedef MichaelList<
+ gc
+ , value_type
+ , typename cds::opt::make_options< traits, Options...>::type
+ > type;
+ };
+
+ // Stat selector
+ template <typename Stat>
+ using select_stat_wrapper = typename base_class::template select_stat_wrapper< Stat >;
+ //@endcond
+
+ protected:
+ //@cond
+ typedef typename base_class::value_type node_type;
+ typedef typename maker::cxx_allocator cxx_allocator;
+ typedef typename maker::node_deallocator node_deallocator;
+ typedef typename maker::intrusive_traits::compare intrusive_key_comparator;
+
+ typedef typename base_class::atomic_node_ptr head_type;
+
+ struct node_disposer {
+ void operator()( node_type * pNode )
+ {
+ free_node( pNode );
+ }
+ };
+ typedef std::unique_ptr< node_type, node_disposer > scoped_node_ptr;
+ //@endcond
+
+ private:
+ //@cond
+ struct raw_ptr_converter
+ {
+ value_type * operator()( node_type * p ) const
+ {
+ return p ? &p->m_Value : nullptr;
+ }
+
+ value_type& operator()( node_type& n ) const
+ {
+ return n.m_Value;
+ }
+
+ value_type const& operator()( node_type const& n ) const
+ {
+ return n.m_Value;
+ }
+ };
+ //@endcond
+
+ public:
+ ///< pointer to extracted node
+ using exempt_ptr = cds::urcu::exempt_ptr< gc, node_type, value_type, typename maker::intrusive_traits::disposer >;
+
+ /// Result of \p get(), \p get_with() functions - pointer to the node found
+ typedef cds::urcu::raw_ptr_adaptor< value_type, typename base_class::raw_ptr, raw_ptr_converter > raw_ptr;
+
+ protected:
+ //@cond
+ template <bool IsConst>
+ class iterator_type: protected base_class::template iterator_type<IsConst>
+ {
+ typedef typename base_class::template iterator_type<IsConst> iterator_base;
+
+ iterator_type( head_type const& pNode )
+ : iterator_base( pNode )
+ {}
+
+ friend class MichaelList;
+
+ public:
+ typedef typename cds::details::make_const_type<value_type, IsConst>::pointer value_ptr;
+ typedef typename cds::details::make_const_type<value_type, IsConst>::reference value_ref;
+
+ iterator_type()
+ {}
+
+ iterator_type( iterator_type const& src )
+ : iterator_base( src )
+ {}
+
+ value_ptr operator ->() const
+ {
+ typename iterator_base::value_ptr p = iterator_base::operator ->();
+ return p ? &(p->m_Value) : nullptr;
+ }
+
+ value_ref operator *() const
+ {
+ return (iterator_base::operator *()).m_Value;
+ }
+
+ /// Pre-increment
+ iterator_type& operator ++()
+ {
+ iterator_base::operator ++();
+ return *this;
+ }
+
+ template <bool C>
+ bool operator ==(iterator_type<C> const& i ) const
+ {
+ return iterator_base::operator ==(i);
+ }
+ template <bool C>
+ bool operator !=(iterator_type<C> const& i ) const
+ {
+ return iterator_base::operator !=(i);
+ }
+ };
+ //@endcond
+
+ public:
+ ///@name Forward iterators (only for debugging purpose)
+ //@{
+ /// Forward iterator
+ /**
+ You may safely use iterators in multi-threaded environment only under RCU lock.
+ Otherwise, a crash is possible if another thread deletes the item the iterator points to.
+ */
+ typedef iterator_type<false> iterator;
+
+ /// Const forward iterator
+ typedef iterator_type<true> const_iterator;
+
+ /// Returns a forward iterator addressing the first element in a list
+ /**
+ For empty list \code begin() == end() \endcode
+ */
+ iterator begin()
+ {
+ return iterator( head());
+ }
+
+ /// Returns an iterator that addresses the location succeeding the last element in a list
+ /**
+ Do not use the value returned by <tt>end</tt> function to access any item.
+ Internally, <tt>end</tt> returning value equals to \p nullptr.
+
+ The returned value can be used only to control reaching the end of the list.
+ For empty list \code begin() == end() \endcode
+ */
+ iterator end()
+ {
+ return iterator();
+ }
+
+ /// Returns a forward const iterator addressing the first element in a list
+ const_iterator begin() const
+ {
+ return const_iterator( head());
+ }
+
+ /// Returns a forward const iterator addressing the first element in a list
+ const_iterator cbegin() const
+ {
+ return const_iterator( head());
+ }
+
+ /// Returns an const iterator that addresses the location succeeding the last element in a list
+ const_iterator end() const
+ {
+ return const_iterator();
+ }
+
+ /// Returns an const iterator that addresses the location succeeding the last element in a list
+ const_iterator cend() const
+ {
+ return const_iterator();
+ }
+ //@}
+
+ public:
+ /// Default constructor
+ /**
+ Initialize empty list
+ */
+ MichaelList()
+ {}
+
+ //@cond
+ template <typename Stat, typename = std::enable_if<std::is_same<stat, michael_list::wrapped_stat<Stat>>::value >>
+ explicit MichaelList( Stat& st )
+ : base_class( st )
+ {}
+ //@endcond
+
+ /// List destructor
+ /**
+ Clears the list
+ */
+ ~MichaelList()
+ {
+ clear();
+ }
+
+ /// Inserts new node
+ /**
+ The function creates a node with copy of \p val value
+ and then inserts the node created into the list.
+
+ The type \p Q should contain as minimum the complete key of the node.
+ The object of \ref value_type should be constructible from \p val of type \p Q.
+ In trivial case, \p Q is equal to \ref value_type.
+
+ The function makes RCU lock internally.
+
+ Returns \p true if inserting successful, \p false otherwise.
+ */
+ template <typename Q>
+ bool insert( Q&& val )
+ {
+ return insert_at( head(), std::forward<Q>( val ));
+ }
+
+ /// Inserts new node
+ /**
+ This function inserts new node with default-constructed value and then it calls
+ \p func functor with signature
+ \code void func( value_type& itemValue ) ;\endcode
+
+ The argument \p itemValue of user-defined functor \p func is the reference
+ to the list's item inserted. User-defined functor \p func should guarantee that during changing
+ item's value no any other changes could be made on this list's item by concurrent threads.
+
+ The type \p Q should contain the complete key of the node.
+ The object of \ref value_type should be constructible from \p key of type \p Q.
+
+ The function allows to split creating of new item into two part:
+ - create item from \p key with initializing key-fields only;
+ - insert new item into the list;
+ - if inserting is successful, initialize non-key fields of item by calling \p f functor
+
+ This can be useful if complete initialization of object of \p value_type is heavyweight and
+ it is preferable that the initialization should be completed only if inserting is successful.
+
+ The function makes RCU lock internally.
+
+ @warning See \ref cds_intrusive_item_creating "insert item troubleshooting"
+ */
+ template <typename Q, typename Func>
+ bool insert( Q&& key, Func func )
+ {
+ return insert_at( head(), std::forward<Q>( key ), func );
+ }
+
+ /// Updates data by \p key
+ /**
+ The operation performs inserting or replacing the element with lock-free manner.
+
+ If the \p key not found in the list, then the new item created from \p key
+ will be inserted iff \p bAllowInsert is \p true.
+ Otherwise, if \p key is found, the functor \p func is called with item found.
+
+ The functor \p Func signature is:
+ \code
+ struct my_functor {
+ void operator()( bool bNew, value_type& item, Q const& val );
+ };
+ \endcode
+
+ with arguments:
+ - \p bNew - \p true if the item has been inserted, \p false otherwise
+ - \p item - item of the list
+ - \p val - argument \p key passed into the \p %update() function
+
+ The functor may change non-key fields of the \p item; however, \p func must guarantee
+ that during changing no any other modifications could be made on this item by concurrent threads.
+
+ The function applies RCU lock internally.
+
+ Returns <tt> std::pair<bool, bool> </tt> where \p first is true if operation is successful,
+ \p second is true if new item has been added or \p false if the item with \p key
+ already exists.
+
+ @warning See \ref cds_intrusive_item_creating "insert item troubleshooting"
+ */
+ template <typename Q, typename Func>
+ std::pair<bool, bool> update( Q const& key, Func func, bool bAllowInsert = true )
+ {
+ return update_at( head(), key, func, bAllowInsert );
+ }
+ //@cond
+ template <typename Q, typename Func>
+ CDS_DEPRECATED("ensure() is deprecated, use update()")
+ std::pair<bool, bool> ensure( Q const& key, Func f )
+ {
+ return update( key, f, true );
+ }
+ //@endcond
+
+ /// Inserts data of type \ref value_type constructed from \p args
+ /**
+ Returns \p true if inserting successful, \p false otherwise.
+
+ The function makes RCU lock internally.
+ */
+ template <typename... Args>
+ bool emplace( Args&&... args )
+ {
+ return emplace_at( head(), std::forward<Args>(args)... );
+ }
+
+ /// Deletes \p key from the list
+ /** \anchor cds_nonintrusive_MichealList_rcu_erase_val
+ Since the key of MichaelList's item type \p value_type is not explicitly specified,
+ template parameter \p Q defines the key type searching in the list.
+ The list item comparator should be able to compare values of the type \p value_type
+ and \p Q in any order.
+
+ RCU \p synchronize method can be called. RCU should not be locked.
+
+ Return \p true if key is found and deleted, \p false otherwise
+ */
+ template <typename Q>
+ bool erase( Q const& key )
+ {
+ return erase_at( head(), key, intrusive_key_comparator(), [](value_type const&){} );
+ }
+
+ /// Deletes the item from the list using \p pred predicate for searching
+ /**
+ The function is an analog of \ref cds_nonintrusive_MichealList_rcu_erase_val "erase(Q const&)"
+ but \p pred is used for key comparing.
+ \p Less functor has the interface like \p std::less.
+ \p pred must imply the same element order as the comparator used for building the list.
+ */
+ template <typename Q, typename Less>
+ bool erase_with( Q const& key, Less pred )
+ {
+ CDS_UNUSED( pred );
+ return erase_at( head(), key, typename maker::template less_wrapper<Less>::type(), [](value_type const&){} );
+ }
+
+ /// Deletes \p key from the list
+ /** \anchor cds_nonintrusive_MichaelList_rcu_erase_func
+ The function searches an item with key \p key, calls \p f functor with item found
+ and deletes it. If \p key is not found, the functor is not called.
+
+ The functor \p Func interface:
+ \code
+ struct functor {
+ void operator()(const value_type& val) { ... }
+ };
+ \endcode
+
+ Since the key of MichaelList's item type \p value_type is not explicitly specified,
+ template parameter \p Q defines the key type searching in the list.
+ The list item comparator should be able to compare the values of type \p value_type
+ and \p Q in any order.
+
+ RCU \p synchronize method can be called. RCU should not be locked.
+
+ Return \p true if key is found and deleted, \p false otherwise
+ */
+ template <typename Q, typename Func>
+ bool erase( Q const& key, Func f )
+ {
+ return erase_at( head(), key, intrusive_key_comparator(), f );
+ }
+
+ /// Deletes the item from the list using \p pred predicate for searching
+ /**
+ The function is an analog of \ref cds_nonintrusive_MichaelList_rcu_erase_func "erase(Q const&, Func)"
+ but \p pred is used for key comparing.
+ \p Less functor has the interface like \p std::less.
+ \p pred must imply the same element order as the comparator used for building the list.
+ */
+ template <typename Q, typename Less, typename Func>
+ bool erase_with( Q const& key, Less pred, Func f )
+ {
+ CDS_UNUSED( pred );
+ return erase_at( head(), key, typename maker::template less_wrapper<Less>::type(), f );
+ }
+
+ /// Extracts an item from the list
+ /**
+ @anchor cds_nonintrusive_MichaelList_rcu_extract
+ The function searches an item with key equal to \p key in the list,
+ unlinks it from the list, and returns \ref cds::urcu::exempt_ptr "exempt_ptr" pointer to the item found.
+ If the item with the key equal to \p key is not found the function returns an empty \p exempt_ptr.
+
+ @note The function does NOT dispose the item found. It just excludes the item from the list
+ and returns a pointer to the item.
+ You shouldn't lock RCU for current thread before calling this function.
+
+ \code
+ #include <cds/urcu/general_buffered.h>
+ #include <cds/container/michael_list_rcu.h>
+
+ typedef cds::urcu::gc< general_buffered<> > rcu;
+ typedef cds::container::MichaelList< rcu, Foo > rcu_michael_list;
+
+ rcu_michael_list theList;
+ // ...
+
+ rcu_michael_list::exempt_ptr p;
+
+ // The RCU should NOT be locked when extract() is called!
+ assert( !rcu::is_locked());
+
+ // extract() call
+ p = theList.extract( 10 )
+ if ( p ) {
+ // do something with p
+ ...
+ }
+
+ // we may safely release extracted pointer here.
+ // release() passes the pointer to RCU reclamation cycle.
+ p.release();
+ \endcode
+ */
+ template <typename Q>
+ exempt_ptr extract( Q const& key )
+ {
+ return exempt_ptr( extract_at( head(), key, intrusive_key_comparator()));
+ }
+
+ /// Extracts an item from the list using \p pred predicate for searching
+ /**
+ This function is the analog for \p extract(Q const&).
+
+ The \p pred is a predicate used for key comparing.
+ \p Less has the interface like \p std::less.
+ \p pred must imply the same element order as \ref key_comparator.
+ */
+ template <typename Q, typename Less>
+ exempt_ptr extract_with( Q const& key, Less pred )
+ {
+ CDS_UNUSED( pred );
+ return exempt_ptr( extract_at( head(), key, typename maker::template less_wrapper<Less>::type()));
+ }
+
+ /// Checks whether the list contains \p key
+ /**
+ The function searches the item with key equal to \p key
+ and returns \p true if it is found, and \p false otherwise.
+
+ The function applies RCU lock internally.
+ */
+ template <typename Q>
+ bool contains( Q const& key )
+ {
+ return find_at( head(), key, intrusive_key_comparator());
+ }
+ //@cond
+ template <typename Q>
+ CDS_DEPRECATED("deprecated, use contains()")
+ bool find( Q const& key )
+ {
+ return contains( key );
+ }
+ //@endcond
+
+ /// Checks whether the list contains \p key using \p pred predicate for searching
+ /**
+ The function is an analog of <tt>contains( key )</tt> but \p pred is used for key comparing.
+ \p Less functor has the interface like \p std::less.
+ \p pred must imply the same element order as the comparator used for building the list.
+ */
+ template <typename Q, typename Less>
+ bool contains( Q const& key, Less pred )
+ {
+ CDS_UNUSED( pred );
+ return find_at( head(), key, typename maker::template less_wrapper<Less>::type());
+ }
+ //@cond
+ // Deprecatd, use contains()
+ template <typename Q, typename Less>
+ bool find_with( Q const& key, Less pred )
+ {
+ CDS_UNUSED( pred );
+ return contains( key, pred );
+ }
+ //@endcond
+
+ /// Finds the key \p key and performs an action with it
+ /** \anchor cds_nonintrusive_MichaelList_rcu_find_func
+ The function searches an item with key equal to \p key and calls the functor \p f for the item found.
+ The interface of \p Func functor is:
+ \code
+ struct functor {
+ void operator()( value_type& item, Q& key );
+ };
+ \endcode
+ where \p item is the item found, \p key is the \p %find() function argument.
+
+ The functor may change non-key fields of \p item. Note that the function is only guarantee
+ that \p item cannot be deleted during functor is executing.
+ The function does not serialize simultaneous access to the list \p item. If such access is
+ possible you must provide your own synchronization schema to exclude unsafe item modifications.
+
+ The function makes RCU lock internally.
+
+ The function returns \p true if \p val is found, \p false otherwise.
+ */
+ template <typename Q, typename Func>
+ bool find( Q& key, Func f )
+ {
+ return find_at( head(), key, intrusive_key_comparator(), f );
+ }
+ //@cond
+ template <typename Q, typename Func>
+ bool find( Q const& key, Func f )
+ {
+ return find_at( head(), key, intrusive_key_comparator(), f );
+ }
+ //@endcond
+
+ /// Finds the key \p key using \p pred predicate for searching
+ /**
+ The function is an analog of \ref cds_nonintrusive_MichaelList_rcu_find_func "find(Q&, Func)"
+ but \p pred is used for key comparing.
+ \p Less functor has the interface like \p std::less.
+ \p pred must imply the same element order as the comparator used for building the list.
+ */
+ template <typename Q, typename Less, typename Func>
+ bool find_with( Q& key, Less pred, Func f )
+ {
+ CDS_UNUSED( pred );
+ return find_at( head(), key, typename maker::template less_wrapper<Less>::type(), f );
+ }
+ //@cond
+ template <typename Q, typename Less, typename Func>
+ bool find_with( Q const& key, Less pred, Func f )
+ {
+ CDS_UNUSED( pred );
+ return find_at( head(), key, typename maker::template less_wrapper<Less>::type(), f );
+ }
+ //@endcond
+
+ /// Finds the key \p key and return the item found
+ /** \anchor cds_nonintrusive_MichaelList_rcu_get
+ The function searches the item with key equal to \p key and returns the pointer to item found.
+ If \p key is not found it returns an empty \p raw_ptr.
+
+ Note the compare functor should accept a parameter of type \p Q that can be not the same as \p value_type.
+
+ RCU should be locked before call of this function.
+ Returned item is valid only while RCU is locked:
+ \code
+ typedef cds::container::MichaelList< cds::urcu::gc< cds::urcu::general_buffered<> >, foo, my_traits > ord_list;
+ ord_list theList;
+ // ...
+ typename ord_list::raw_ptr rp;
+ {
+ // Lock RCU
+ ord_list::rcu_lock lock;
+
+ rp = theList.get( 5 );
+ if ( rp ) {
+ // Deal with rp
+ //...
+ }
+ // Unlock RCU by rcu_lock destructor
+ // A value owned by rp can be freed at any time after RCU has been unlocked
+ }
+ // You can manually release rp after RCU-locked section
+ rp.release();
+ \endcode
+ */
+ template <typename Q>
+ raw_ptr get( Q const& key )
+ {
+ return get_at( head(), key, intrusive_key_comparator());
+ }
+
+ /// Finds \p key and return the item found
+ /**
+ The function is an analog of \ref cds_nonintrusive_MichaelList_rcu_get "get(Q const&)"
+ but \p pred is used for comparing the keys.
+
+ \p Less functor has the semantics like \p std::less but should take arguments of type \ref value_type and \p Q
+ in any order.
+ \p pred must imply the same element order as the comparator used for building the list.
+ */
+ template <typename Q, typename Less>
+ raw_ptr get_with( Q const& key, Less pred )
+ {
+ CDS_UNUSED( pred );
+ return get_at( head(), key, typename maker::template less_wrapper<Less>::type());
+ }
+
+ /// Checks if the list is empty
+ bool empty() const
+ {
+ return base_class::empty();
+ }
+
+ /// Returns list's item count
+ /**
+ The value returned depends on item counter provided by \p Traits. For \p atomicity::empty_item_counter,
+ this function always returns 0.
+
+ @note Even if you use real item counter and it returns 0, this fact does not mean that the list
+ is empty. To check list emptyness use \p empty() method.
+ */
+ size_t size() const
+ {
+ return base_class::size();
+ }
+
+ /// Returns const reference to internal statistics
+ stat const& statistics() const
+ {
+ return base_class::statistics();
+ }
+
+ /// Clears the list
+ void clear()
+ {
+ base_class::clear();
+ }
+
+ protected:
+ //@cond
+ bool insert_node( node_type * pNode )
+ {
+ return insert_node_at( head(), pNode );
+ }
+
+ bool insert_node_at( head_type& refHead, node_type * pNode )
+ {
+ assert( pNode );
+ scoped_node_ptr p(pNode);
+ if ( base_class::insert_at( refHead, *pNode )) {
+ p.release();
+ return true;
+ }
+
+ return false;
+ }
+
+ template <typename Q>
+ bool insert_at( head_type& refHead, Q&& val )
+ {
+ return insert_node_at( refHead, alloc_node( std::forward<Q>( val )));
+ }
+
+ template <typename Q, typename Func>
+ bool insert_at( head_type& refHead, Q&& key, Func f )
+ {
+ scoped_node_ptr pNode( alloc_node( std::forward<Q>( key )));
+
+ if ( base_class::insert_at( refHead, *pNode, [&f]( node_type& node ) { f( node_to_value(node)); } )) {
+ pNode.release();
+ return true;
+ }
+ return false;
+ }
+
+ template <typename... Args>
+ bool emplace_at( head_type& refHead, Args&&... args )
+ {
+ return insert_node_at( refHead, alloc_node( std::forward<Args>(args) ... ));
+ }
+
+ template <typename Q, typename Compare, typename Func>
+ bool erase_at( head_type& refHead, Q const& key, Compare cmp, Func f )
+ {
+ return base_class::erase_at( refHead, key, cmp, [&f](node_type const& node){ f( node_to_value(node)); } );
+ }
+
+ template <typename Q, typename Func>
+ std::pair<bool, bool> update_at( head_type& refHead, Q const& key, Func f, bool bAllowInsert )
+ {
+ scoped_node_ptr pNode( alloc_node( key ));
+
+ std::pair<bool, bool> ret = base_class::update_at( refHead, *pNode,
+ [&f, &key](bool bNew, node_type& node, node_type&){ f( bNew, node_to_value(node), key );},
+ bAllowInsert );
+ if ( ret.first && ret.second )
+ pNode.release();
+
+ return ret;
+ }
+
+ template <typename Q, typename Compare>
+ node_type * extract_at( head_type& refHead, Q const& key, Compare cmp )
+ {
+ return base_class::extract_at( refHead, key, cmp );
+ }
+
+ template <typename Q, typename Compare>
+ bool find_at( head_type& refHead, Q const& key, Compare cmp )
+ {
+ return base_class::find_at( refHead, key, cmp, [](node_type&, Q const &) {} );
+ }
+
+ template <typename Q, typename Compare, typename Func>
+ bool find_at( head_type& refHead, Q& val, Compare cmp, Func f )
+ {
+ return base_class::find_at( refHead, val, cmp, [&f](node_type& node, Q& v){ f( node_to_value(node), v ); });
+ }
+
+ template <typename Q, typename Compare>
+ raw_ptr get_at( head_type& refHead, Q const& val, Compare cmp )
+ {
+ return raw_ptr( base_class::get_at( refHead, val, cmp ));
+ }
+
+ static value_type& node_to_value( node_type& n )
+ {
+ return n.m_Value;
+ }
+ static value_type const& node_to_value( node_type const& n )
+ {
+ return n.m_Value;
+ }
+
+ template <typename Q>
+ static node_type * alloc_node( Q&& v )
+ {
+ return cxx_allocator().New( std::forward<Q>( v ));
+ }
+
+ template <typename... Args>
+ static node_type * alloc_node( Args&&... args )
+ {
+ return cxx_allocator().MoveNew( std::forward<Args>( args )... );
+ }
+
+ static void free_node( node_type * pNode )
+ {
+ cxx_allocator().Delete( pNode );
+ }
+
+ head_type& head()
+ {
+ return base_class::m_pHead;
+ }
+
+ head_type& head() const
+ {
+ return const_cast<head_type&>(base_class::m_pHead);
+ }
+ //@endcond
+ };
+
+}} // namespace cds::container
+
+#endif // #ifndef CDSLIB_CONTAINER_MICHAEL_LIST_RCU_H