--- /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_SPLIT_LIST_MAP_RCU_H
+#define CDSLIB_CONTAINER_SPLIT_LIST_MAP_RCU_H
+
+#include <cds/container/split_list_set_rcu.h>
+#include <cds/details/binary_functor_wrapper.h>
+
+namespace cds { namespace container {
+
+ /// Split-ordered list map (template specialization for \ref cds_urcu_desc "RCU")
+ /** @ingroup cds_nonintrusive_map
+ \anchor cds_nonintrusive_SplitListMap_rcu
+
+ Hash table implementation based on split-ordered list algorithm discovered by Ori Shalev and Nir Shavit, see
+ - [2003] Ori Shalev, Nir Shavit "Split-Ordered Lists - Lock-free Resizable Hash Tables"
+ - [2008] Nir Shavit "The Art of Multiprocessor Programming"
+
+ See intrusive::SplitListSet for a brief description of the split-list algorithm.
+
+ Template parameters:
+ - \p RCU - one of \ref cds_urcu_gc "RCU type"
+ - \p Key - key type to be stored in the map
+ - \p Value - value type to be stored in the map
+ - \p Traits - type traits, default is \p split_list::traits. Instead of declaring \p %split_list::traits -based
+ struct you may apply option-based notation with \p split_list::make_traits metafunction.
+
+ <b>Iterators</b>
+
+ The class supports a forward unordered iterator (\ref iterator and \ref const_iterator).
+ You may iterate over split-list map items only under RCU lock.
+ Only in this case the iterator is thread-safe since
+ while RCU is locked any map's item cannot be reclaimed.
+ The requirement of RCU lock during iterating means that deletion of the elements
+ is not possible.
+
+ @warning The iterator object cannot be passed between threads.
+ Due to concurrent nature of split-list map it is not guarantee that you can iterate
+ all elements in the map: any concurrent deletion can exclude the element
+ pointed by the iterator from the map, and your iteration can be terminated
+ before end of the map. Therefore, such iteration is more suitable for debugging purposes
+
+ The iterator class supports the following minimalistic interface:
+ \code
+ struct iterator {
+ // Default ctor
+ iterator();
+
+ // Copy ctor
+ iterator( iterator const& s);
+
+ value_type * operator ->() const;
+ value_type& operator *() const;
+
+ // Pre-increment
+ iterator& operator ++();
+
+ // Copy assignment
+ iterator& operator = (const iterator& src);
+
+ bool operator ==(iterator const& i ) const;
+ bool operator !=(iterator const& i ) const;
+ };
+ \endcode
+ Note, the iterator object returned by \ref end, \p cend member functions points to \p nullptr and should not be dereferenced.
+
+ \par Usage
+
+ You should decide what garbage collector you want, and what ordered list you want to use. Split-ordered list
+ is original data structure based on an ordered list. Suppose, you want construct split-list map based on \p cds::urcu::general_buffered<> GC
+ and \p MichaelList as ordered list implementation. Your map should map \p int key to \p std::string value.
+ So, you beginning your program with following include:
+ \code
+ #include <cds/urcu/general_buffered.h>
+ #include <cds/container/michael_list_rcu.h>
+ #include <cds/container/split_list_map_rcu.h>
+
+ namespace cc = cds::container;
+ \endcode
+ The inclusion order is important:
+ - first, include one of \ref cds_urcu_gc "RCU implementation" (<tt>cds/urcu/general_buffered.h</tt> in our case)
+ - second, include the header of ordered-list implementation (for this example, <tt>cds/container/michael_list_rcu.h</tt>),
+ - then, the header for RCU-based split-list map <tt>cds/container/split_list_map_rcu.h</tt>.
+
+ Now, you should declare traits for split-list map. The main parts of traits are a hash functor for the map key and a comparing functor for ordered list.
+ We use \p std::hash<int> and \p std::less<int>.
+
+ The second attention: instead of using \p %MichaelList in \p %SplitListMap traits we use a tag \p ds::contaner::michael_list_tag
+ for the Michael's list.
+ The split-list requires significant support from underlying ordered list class and it is not good idea to dive you
+ into deep implementation details of split-list and ordered list interrelations. The tag paradigm simplifies split-list interface.
+
+ \code
+ // SplitListMap traits
+ struct foo_set_traits: public cc::split_list::traits
+ {
+ typedef cc::michael_list_tag ordered_list ; // what type of ordered list we want to use
+ typedef std::hash<int> hash ; // hash functor for the key stored in split-list map
+
+ // Type traits for our MichaelList class
+ struct ordered_list_traits: public cc::michael_list::traits
+ {
+ typedef std::less<int> less ; // use our std::less predicate as comparator to order list nodes
+ };
+ };
+ \endcode
+
+ Now you are ready to declare our map class based on \p %SplitListMap:
+ \code
+ typedef cc::SplitListMap< cds::urcu::gc<cds::urcu::general_buffered<> >, int, std::string, foo_set_traits > int_string_map;
+ \endcode
+
+ You may use the modern option-based declaration instead of classic traits-based one:
+ \code
+ typedef cc::SplitListMap<
+ cds::urcu::gc<cds::urcu::general_buffered<> > // RCU type
+ ,int // key type
+ ,std::string // value type
+ ,cc::split_list::make_traits< // metafunction to build split-list traits
+ cc::split_list::ordered_list<cc::michael_list_tag> // tag for underlying ordered list implementation
+ ,cc::opt::hash< std::hash<int> > // hash functor
+ ,cc::split_list::ordered_list_traits< // ordered list traits desired
+ cc::michael_list::make_traits< // metafunction to build lazy list traits
+ cc::opt::less< std::less<int> > // less-based compare functor
+ >::type
+ >
+ >::type
+ > int_string_map;
+ \endcode
+ In case of option-based declaration using \p split_list::make_traits metafunction the struct \p foo_set_traits is not required.
+
+ Now, the map of type \p int_string_map is ready to use in your program.
+
+ Note that in this example we show only mandatory \p traits parts, optional ones is the default and they are inherited
+ from cds::container::split_list::traits.
+ There are many other useful options for deep tuning the split-list and ordered-list containers.
+ */
+ template <
+ class RCU,
+ typename Key,
+ typename Value,
+#ifdef CDS_DOXYGEN_INVOKED
+ class Traits = split_list::traits
+#else
+ class Traits
+#endif
+ >
+ class SplitListMap< cds::urcu::gc< RCU >, Key, Value, Traits >:
+ protected container::SplitListSet<
+ cds::urcu::gc< RCU >,
+ std::pair<Key const, Value>,
+ split_list::details::wrap_map_traits<Key, Value, Traits>
+ >
+ {
+ //@cond
+ typedef container::SplitListSet<
+ cds::urcu::gc< RCU >,
+ std::pair<Key const, Value>,
+ split_list::details::wrap_map_traits<Key, Value, Traits>
+ > base_class;
+ //@endcond
+
+ public:
+ typedef cds::urcu::gc< RCU > gc; ///< Garbage collector
+ typedef Key key_type; ///< key type
+ typedef Value mapped_type; ///< type of value to be stored in the map
+ typedef Traits traits; ///< Map traits
+
+ typedef std::pair<key_type const, mapped_type> value_type; ///< key-value pair type
+ typedef typename base_class::ordered_list ordered_list; ///< Underlying ordered list class
+ typedef typename base_class::key_comparator key_comparator; ///< key comparison functor
+
+ typedef typename base_class::hash hash; ///< Hash functor for \ref key_type
+ typedef typename base_class::item_counter item_counter; ///< Item counter type
+ typedef typename base_class::stat stat; ///< Internal statistics
+
+ typedef typename base_class::rcu_lock rcu_lock; ///< RCU scoped lock
+ typedef typename base_class::exempt_ptr exempt_ptr; ///< pointer to extracted node
+ /// Group of \p extract_xxx functions require external locking if underlying ordered list requires that
+ static constexpr const bool c_bExtractLockExternal = base_class::c_bExtractLockExternal;
+ typedef typename base_class::raw_ptr raw_ptr; ///< type of \p get() return value
+
+ protected:
+ //@cond
+ typedef typename base_class::maker::traits::key_accessor key_accessor;
+ //@endcond
+
+ public:
+ /// Forward iterator
+ typedef typename base_class::iterator iterator;
+
+ /// Const forward iterator
+ typedef typename base_class::const_iterator const_iterator;
+
+ /// Returns a forward iterator addressing the first element in a map
+ /**
+ For empty map \code begin() == end() \endcode
+ */
+ iterator begin()
+ {
+ return base_class::begin();
+ }
+
+ /// Returns an iterator that addresses the location succeeding the last element in a map
+ /**
+ Do not use the value returned by <tt>end</tt> function to access any item.
+ The returned value can be used only to control reaching the end of the map.
+ For empty map \code begin() == end() \endcode
+ */
+ iterator end()
+ {
+ return base_class::end();
+ }
+
+ /// Returns a forward const iterator addressing the first element in a map
+ //@{
+ const_iterator begin() const
+ {
+ return base_class::begin();
+ }
+ const_iterator cbegin() const
+ {
+ return base_class::cbegin();
+ }
+ //@}
+
+ /// Returns an const iterator that addresses the location succeeding the last element in a map
+ //@{
+ const_iterator end() const
+ {
+ return base_class::end();
+ }
+ const_iterator cend() const
+ {
+ return base_class::cend();
+ }
+ //@}
+
+ public:
+ /// Initializes split-ordered map of default capacity
+ /**
+ The default capacity is defined in bucket table constructor.
+ See \p intrusive::split_list::expandable_bucket_table, \p intrusive::split_list::static_bucket_table
+ which selects by \p split_list::dynamic_bucket_table option.
+ */
+ SplitListMap()
+ : base_class()
+ {}
+
+ /// Initializes split-ordered map
+ SplitListMap(
+ size_t nItemCount ///< estimated average item count
+ , size_t nLoadFactor = 1 ///< load factor - average item count per bucket. Small integer up to 10, default is 1.
+ )
+ : base_class( nItemCount, nLoadFactor )
+ {}
+
+ public:
+ /// Inserts new node with key and default value
+ /**
+ The function creates a node with \p key and the default value, and then inserts the node created into the map.
+
+ Preconditions:
+ - The \p key_type should be constructible from value of type \p K.
+ - The \p mapped_type should be default-constructible.
+
+ The function applies RCU lock internally.
+
+ Returns \p true if inserting successful, \p false otherwise.
+ */
+ template <typename K>
+ bool insert( K const& key )
+ {
+ return base_class::emplace( key_type( key ), mapped_type());
+ }
+
+ /// Inserts new node
+ /**
+ The function creates a node with copy of \p val value
+ and then inserts the node into the map.
+
+ Preconditions:
+ - The \p key_type should be constructible from \p key of type \p K.
+ - The \p mapped_type should be constructible from \p val of type \p V.
+
+ The function applies RCU lock internally.
+
+ Returns \p true if \p val is inserted into the map, \p false otherwise.
+ */
+ template <typename K, typename V>
+ bool insert( K const& key, V const& val )
+ {
+ //TODO: pass arguments by reference (make_pair makes copy)
+ return base_class::emplace( key_type( key ), mapped_type( val ));
+ }
+
+ /// Inserts new node and initialize it by a functor
+ /**
+ This function inserts new node with key \p key and if inserting is successful then it calls
+ \p func functor with signature
+ \code
+ struct functor {
+ void operator()( value_type& item );
+ };
+ \endcode
+
+ The argument \p item of user-defined functor \p func is the reference
+ to the map's item inserted:
+ - <tt>item.first</tt> is a const reference to item's key that cannot be changed.
+ - <tt>item.second</tt> is a reference to item's value that may be changed.
+
+ It should be keep in mind that concurrent modifications of \p <tt>item.second</tt> in \p func body
+ should be careful. You shouldf guarantee that during changing item's value in \p func no any other changes
+ could be made on this \p item by concurrent threads.
+
+ \p func is called only if inserting is successful.
+
+ The function allows to split creating of new item into two part:
+ - create item from \p key;
+ - insert new item into the map;
+ - if inserting is successful, initialize the value of item by calling \p func functor
+
+ This can be useful if complete initialization of object of \p mapped_type is heavyweight and
+ it is preferable that the initialization should be completed only if inserting is successful.
+
+ The function applies RCU lock internally.
+ */
+ template <typename K, typename Func>
+ bool insert_with( K const& key, Func func )
+ {
+ //TODO: pass arguments by reference (make_pair makes copy)
+ return base_class::insert( std::make_pair( key_type( key ), mapped_type()), func );
+ }
+
+ /// For key \p key inserts data of type \p mapped_type created in-place from \p args
+ /**
+ \p key_type should be constructible from type \p K
+
+ The function applies RCU lock internally.
+
+ Returns \p true if inserting successful, \p false otherwise.
+ */
+ template <typename K, typename... Args>
+ bool emplace( K&& key, Args&&... args )
+ {
+ return base_class::emplace( key_type( std::forward<K>( key )), mapped_type( std::forward<Args>(args)... ));
+ }
+
+ /// 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 map, then the new item created from \p key
+ will be inserted into the map iff \p bAllowInsert is \p true.
+ (note that in this case the \ref key_type should be constructible from type \p K).
+ 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 );
+ };
+ \endcode
+ with arguments:
+ - \p bNew - \p true if the item has been inserted, \p false otherwise
+ - \p item - the item found or inserted
+
+ The functor may change any fields of the \p item.second that is \p mapped_type.
+
+ 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 For \ref cds_nonintrusive_MichaelKVList_gc "MichaelKVList" as the ordered list see \ref cds_intrusive_item_creating "insert item troubleshooting".
+ \ref cds_nonintrusive_LazyKVList_gc "LazyKVList" provides exclusive access to inserted item and does not require any node-level
+ synchronization.
+ */
+ template <typename K, typename Func>
+ std::pair<bool, bool> update( K const& key, Func func, bool bAllowInsert = true )
+ {
+ //TODO: pass arguments by reference (make_pair makes copy)
+ typedef decltype( std::make_pair( key_type( key ), mapped_type())) arg_pair_type;
+
+ return base_class::update( std::make_pair( key_type( key ), mapped_type()),
+ [&func]( bool bNew, value_type& item, arg_pair_type const& /*val*/ ) {
+ func( bNew, item );
+ },
+ bAllowInsert );
+ }
+ //@cond
+ template <typename K, typename Func>
+ CDS_DEPRECATED("ensure() is deprecated, use update()")
+ std::pair<bool, bool> ensure( K const& key, Func func )
+ {
+ return update( key, func, true );
+ }
+ //@endcond
+
+ /// Deletes \p key from the map
+ /** \anchor cds_nonintrusive_SplitListMap_rcu_erase_val
+
+ RCU \p synchronize method can be called. RCU should not be locked.
+
+ Return \p true if \p key is found and deleted, \p false otherwise
+ */
+ template <typename K>
+ bool erase( K const& key )
+ {
+ return base_class::erase( key );
+ }
+
+ /// Deletes the item from the map using \p pred predicate for searching
+ /**
+ The function is an analog of \ref cds_nonintrusive_SplitListMap_rcu_erase_val "erase(K const&)"
+ but \p pred is used for key comparing.
+ \p Less functor has the interface like \p std::less.
+ \p Less must imply the same element order as the comparator used for building the map.
+ */
+ template <typename K, typename Less>
+ bool erase_with( K const& key, Less pred )
+ {
+ CDS_UNUSED( pred );
+ return base_class::erase_with( key, cds::details::predicate_wrapper<value_type, Less, key_accessor>());
+ }
+
+ /// Deletes \p key from the map
+ /** \anchor cds_nonintrusive_SplitListMap_rcu_erase_func
+
+ The function searches an item with key \p key, calls \p f functor
+ and deletes the item. If \p key is not found, the functor is not called.
+
+ The functor \p Func interface is:
+ \code
+ struct extractor {
+ void operator()(value_type& item) { ... }
+ };
+ \endcode
+
+ 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 K, typename Func>
+ bool erase( K const& key, Func f )
+ {
+ return base_class::erase( key, f );
+ }
+
+ /// Deletes the item from the map using \p pred predicate for searching
+ /**
+ The function is an analog of \ref cds_nonintrusive_SplitListMap_rcu_erase_func "erase(K const&, Func)"
+ but \p pred is used for key comparing.
+ \p Less functor has the interface like \p std::less.
+ \p Less must imply the same element order as the comparator used for building the map.
+ */
+ template <typename K, typename Less, typename Func>
+ bool erase_with( K const& key, Less pred, Func f )
+ {
+ CDS_UNUSED( pred );
+ return base_class::erase_with( key, cds::details::predicate_wrapper<value_type, Less, key_accessor>(), f );
+ }
+
+ /// Extracts an item from the map
+ /** \anchor cds_nonintrusive_SplitListMap_rcu_extract
+ The function searches an item with key equal to \p key in the map,
+ unlinks it from the map, 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.
+
+ Depends on ordered list you should or should not lock RCU before calling of this function:
+ - for the set based on \ref cds_intrusive_MichaelList_rcu "MichaelList" RCU should not be locked
+ - for the set based on \ref cds_intrusive_LazyList_rcu "LazyList" RCU should be locked
+ See ordered list implementation for details.
+
+ \code
+ typedef cds::urcu::gc< general_buffered<> > rcu;
+
+ // Split-list set based on MichaelList by default
+ typedef cds::container::SplitListMap< rcu, int, Foo > splitlist_map;
+
+ splitlist_map theMap;
+ // ...
+
+ typename splitlist_map::exempt_ptr p;
+
+ // For MichaelList we should not lock RCU
+
+ // Now, you can apply extract function
+ p = theMap.extract( 10 )
+ if ( p ) {
+ // do something with p
+ ...
+ }
+
+ // We may safely release p here
+ // release() passes the pointer to RCU reclamation cycle
+ p.release();
+ \endcode
+ */
+ template <typename K>
+ exempt_ptr extract( K const& key )
+ {
+ return base_class::extract( key );
+ }
+
+ /// Extracts an item from the map using \p pred predicate for searching
+ /**
+ The function is an analog of \p extract(K 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 map.
+ */
+ template <typename K, typename Less>
+ exempt_ptr extract_with( K const& key, Less pred )
+ {
+ CDS_UNUSED( pred );
+ return base_class::extract_with( key, cds::details::predicate_wrapper<value_type, Less, key_accessor>());
+ }
+
+ /// Finds the key \p key
+ /** \anchor cds_nonintrusive_SplitListMap_rcu_find_cfunc
+
+ The function searches the item with key equal to \p key and calls the functor \p f for item found.
+ The interface of \p Func functor is:
+ \code
+ struct functor {
+ void operator()( value_type& item );
+ };
+ \endcode
+ where \p item is the item found.
+
+ The functor may change \p item.second. Note that the functor is only guarantee
+ that \p item cannot be disposed during functor is executing.
+ The functor does not serialize simultaneous access to the map's \p item. If such access is
+ possible you must provide your own synchronization schema on item level to exclude unsafe item modifications.
+
+ The function applies RCU lock internally.
+
+ The function returns \p true if \p key is found, \p false otherwise.
+ */
+ template <typename K, typename Func>
+ bool find( K const& key, Func f )
+ {
+ return base_class::find( key, [&f](value_type& pair, K const&){ f( pair ); } );
+ }
+
+ /// Finds the key \p key using \p pred predicate for searching
+ /**
+ The function is an analog of \ref cds_nonintrusive_SplitListMap_rcu_find_cfunc "find(K const&, Func)"
+ but \p pred is used for key comparing.
+ \p Less functor has the interface like \p std::less.
+ \p Less must imply the same element order as the comparator used for building the map.
+ */
+ template <typename K, typename Less, typename Func>
+ bool find_with( K const& key, Less pred, Func f )
+ {
+ CDS_UNUSED( pred );
+ return base_class::find_with( key,
+ cds::details::predicate_wrapper<value_type, Less, key_accessor>(),
+ [&f](value_type& pair, K const&){ f( pair ); } );
+ }
+
+ /// Checks whether the map 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 K>
+ bool contains( K const& key )
+ {
+ return base_class::contains( key );
+ }
+ //@cond
+ template <typename K>
+ CDS_DEPRECATED("deprecated, use contains()")
+ bool find( K const& key )
+ {
+ return base_class::find( key );
+ }
+ //@endcond
+
+ /// Checks whether the map 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 Less must imply the same element order as the comparator used for building the map.
+ */
+ template <typename K, typename Less>
+ bool contains( K const& key, Less pred )
+ {
+ CDS_UNUSED( pred );
+ return base_class::contains( key, cds::details::predicate_wrapper<value_type, Less, key_accessor>());
+ }
+ //@cond
+ template <typename K, typename Less>
+ CDS_DEPRECATED("deprecated, use contains()")
+ bool find_with( K const& key, Less pred )
+ {
+ return contains( key, pred );
+ }
+ //@endcond
+
+ /// Finds \p key and return the item found
+ /** \anchor cds_intrusive_SplitListMap_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 empty \p raw_ptr.
+
+ Note the compare functor should accept a parameter of type \p K 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::urcu::gc< general_buffered<> > rcu;
+ typedef cds::container::SplitListMap< rcu, int, Foo > splitlist_map;
+ splitlist_map theMap;
+ // ...
+ {
+ // Lock RCU
+ typename splitlist_map::rcu_lock lock;
+
+ typename splitlist_map::raw_ptr pVal = theMap.get( 5 );
+ if ( pVal ) {
+ // Deal with pVal
+ //...
+ }
+ // Unlock RCU by rcu_lock destructor
+ // pVal can be retired by disposer at any time after RCU has been unlocked
+ }
+ \endcode
+ */
+ template <typename K>
+ raw_ptr get( K const& key )
+ {
+ return base_class::get( key );
+ }
+
+ /// Finds \p key with predicate specified and return the item found
+ /**
+ The function is an analog of \ref cds_intrusive_SplitListMap_rcu_get "get(K 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 K
+ in any order.
+ \p pred must imply the same element order as the comparator used for building the map.
+ */
+ template <typename K, typename Less>
+ raw_ptr get_with( K const& key, Less pred )
+ {
+ CDS_UNUSED( pred );
+ return base_class::get_with( key, cds::details::predicate_wrapper<value_type, Less, key_accessor>());
+ }
+
+ /// Clears the map (not atomic)
+ void clear()
+ {
+ base_class::clear();
+ }
+
+ /// Checks if the map is empty
+ /**
+ Emptiness is checked by item counting: if item count is zero then the map is empty.
+ Thus, the correct item counting is an important part of the map implementation.
+ */
+ bool empty() const
+ {
+ return base_class::empty();
+ }
+
+ /// Returns item count in the map
+ size_t size() const
+ {
+ return base_class::size();
+ }
+
+ /// Returns internal statistics
+ stat const& statistics() const
+ {
+ return base_class::statistics();
+ }
+
+ /// Returns internal statistics for \p ordered_list
+ typename ordered_list::stat const& list_statistics() const
+ {
+ return base_class::list_statistics();
+ }
+ };
+
+}} // namespace cds::container
+
+#endif // #ifndef CDSLIB_CONTAINER_SPLIT_LIST_MAP_RCU_H
projects / c11concurrency-benchmarks.git / blobdiff