-//$$CDS-header$$
+/*
+ This file is a part of libcds - Concurrent Data Structures library
+
+ (C) Copyright Maxim Khizhinsky (libcds.dev@gmail.com) 2006-2016
+
+ 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
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
using exempt_ptr = cds::urcu::exempt_ptr< gc, node_type, value_type, typename maker::intrusive_traits::disposer >; ///< pointer to extracted node
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:
+ /// 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
static value_type& node_to_value( node_type& n )
{
{
return n.m_Value;
}
- //@endcond
- protected:
- //@cond
template <typename Q>
static node_type * alloc_node( Q const& v )
{
//@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
}
/// 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
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
return insert_at( head(), key, func );
}
- /// Ensures that the \p key exists in the list
+ /// Updates data by \p key
/**
- The operation performs inserting or changing data with lock-free manner.
+ 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
- is inserted into the list. Otherwise, the functor \p func is called with the item found.
- The functor \p Func should be a function with signature:
- \code
- void func( bool bNew, value_type& item, const Q& val );
- \endcode
- or a functor:
+ 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, const Q& val );
+ 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 ensure function
+ - \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 makes RCU lock internally.
+ The function applies RCU lock internally.
- Returns <tt> std::pair<bool, bool> </tt> where \p first is true if operation is successfull,
+ 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 is in the list.
+ 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 ensure_at( head(), key, f );
+ return update( key, f, true );
}
+ //@endcond
/// Inserts data of type \ref value_type constructed from \p args
/**
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 item found.
- You shouldn't lock RCU before calling this function.
+ 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>
// The RCU should NOT be locked when extract() is called!
assert( !rcu::is_locked() );
-
+
// extract() call
p = theList.extract( 10 )
if ( p ) {
return exempt_ptr( extract_at( head(), key, typename maker::template less_wrapper<Less>::type() ));
}
- /// Finds the key \p key
- /** \anchor cds_nonintrusive_MichaelList_rcu_find_val
+ /// 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 makes RCU lock internally.
+ The function applies RCU lock internally.
*/
template <typename Q>
- bool find( Q const& key )
+ 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
- /// Finds the key \p val using \p pred predicate for searching
+ /// Checks whether the list contains \p key using \p pred predicate for searching
/**
- The function is an analog of \ref cds_nonintrusive_MichaelList_rcu_find_val "find(Q const&)"
- but \p pred is used for key comparing.
+ 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 find_with( Q const& key, Less pred )
+ 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
/// 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 \p nullptr.
+ 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.
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;
- foo * pVal = theList.get( 5 );
- if ( pVal ) {
- // Deal with pVal
+ rp = theList.get( 5 );
+ if ( rp ) {
+ // Deal with rp
//...
}
// Unlock RCU by rcu_lock destructor
- // pVal can be freed at any time after RCU has been unlocked
+ // 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>
- value_type * get( Q const& key )
+ raw_ptr get( Q const& key )
{
return get_at( head(), key, intrusive_key_comparator());
}
\p pred must imply the same element order as the comparator used for building the list.
*/
template <typename Q, typename Less>
- value_type * get_with( Q const& key, Less pred )
+ raw_ptr get_with( Q const& key, Less pred )
{
CDS_UNUSED( pred );
return get_at( head(), key, typename maker::template less_wrapper<Less>::type());
return base_class::size();
}
+ /// Returns const reference to internal statistics
+ stat const& statistics() const
+ {
+ return base_class::statistics();
+ }
+
/// Clears the list
void 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 );
}
template <typename Q, typename Func>
- std::pair<bool, bool> ensure_at( head_type& refHead, Q const& key, Func f )
+ 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::ensure_at( refHead, *pNode,
- [&f, &key](bool bNew, node_type& node, node_type&){ f( bNew, node_to_value(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();
}
template <typename Q, typename Compare>
- value_type * get_at( head_type& refHead, Q const& val, Compare cmp )
+ raw_ptr get_at( head_type& refHead, Q const& val, Compare cmp )
{
- node_type * pNode = base_class::get_at( refHead, val, cmp );
- return pNode ? &pNode->m_Value : nullptr;
+ return raw_ptr( base_class::get_at( refHead, val, cmp ));
}
//@endcond