-//$$CDS-header$$
-
-#ifndef __CDS_CONTAINER_IMPL_MICHAEL_LIST_H
-#define __CDS_CONTAINER_IMPL_MICHAEL_LIST_H
+/*
+ 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_IMPL_MICHAEL_LIST_H
+#define CDSLIB_CONTAINER_IMPL_MICHAEL_LIST_H
#include <memory>
#include <cds/container/details/guarded_ptr_cast.h>
typedef typename maker::key_comparator key_comparator; ///< key comparison functor
typedef typename base_class::memory_model memory_model; ///< Memory ordering. See \p cds::opt::memory_model option
+ static CDS_CONSTEXPR const size_t c_nHazardPtrCount = base_class::c_nHazardPtrCount; ///< Count of hazard pointer required for the algorithm
+
protected:
//@cond
typedef typename base_class::value_type node_type;
public:
/// Guarded pointer
- typedef cds::gc::guarded_ptr< gc, node_type, value_type, details::guarded_ptr_cast_set<node_type, value_type> > guarded_ptr;
+ typedef typename gc::template guarded_ptr< node_type, value_type, details::guarded_ptr_cast_set<node_type, value_type> > guarded_ptr;
- private:
+ 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
/**
The forward iterator for Michael's list has some features:
- The iterator cannot be moved across thread boundary since it contains GC's guard that is thread-private GC data.
- Iterator ensures thread-safety even if you delete the item that iterator points to. However, in case of concurrent
deleting operations it is no guarantee that you iterate all item in the list.
+ Moreover, a crash is possible when you try to iterate the next element that has been deleted by concurrent thread.
- Therefore, the use of iterators in concurrent environment is not good idea. Use the iterator on the concurrent container
- for debug purpose only.
+ @warning Use this iterator on the concurrent container for debugging purpose only.
*/
typedef iterator_type<false> 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
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.
- 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 func )
{
- return ensure_at( head(), key, func );
+ return update( key, func );
}
+ //@endcond
/// Inserts data of type \p value_type constructed with <tt>std::forward<Args>(args)...</tt>
/**
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&){} );
}
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 the item from the list with specified \p key
/** \anchor cds_nonintrusive_MichaelList_hp_extract
The function searches an item with key equal to \p key,
- unlinks it from the list, and returns it in \p dest parameter.
- If the item with key equal to \p key is not found the function returns \p false.
+ unlinks it from the list, and returns it as \p guarded_ptr.
+ If \p key is not found the function returns an empty guarded pointer.
Note the compare functor should accept a parameter of type \p Q that can be not the same as \p value_type.
ord_list theList;
// ...
{
- ord_list::guarded_ptr gp;
- theList.extract( gp, 5 );
- // Deal with gp
- // ...
-
+ ord_list::guarded_ptr gp(theList.extract( 5 ));
+ if ( gp ) {
+ // Deal with gp
+ // ...
+ }
// Destructor of gp releases internal HP guard and frees the item
}
\endcode
*/
template <typename Q>
- bool extract( guarded_ptr& dest, Q const& key )
+ guarded_ptr extract( Q const& key )
{
- return extract_at( head(), dest.guard(), key, intrusive_key_comparator() );
+ guarded_ptr gp;
+ extract_at( head(), gp.guard(), key, intrusive_key_comparator() );
+ return gp;
}
/// Extracts the item from the list with comparing functor \p pred
/**
- The function is an analog of \ref cds_nonintrusive_MichaelList_hp_extract "extract(guarded_ptr&, Q const&)"
+ The function is an analog of \ref cds_nonintrusive_MichaelList_hp_extract "extract(Q const&)"
but \p pred predicate is used for key comparing.
\p Less functor has the semantics like \p std::less but it should accept arguments of type \p value_type and \p Q
\p pred must imply the same element order as the comparator used for building the list.
*/
template <typename Q, typename Less>
- bool extract_with( guarded_ptr& dest, Q const& key, Less pred )
+ guarded_ptr extract_with( Q const& key, Less pred )
{
- return extract_at( head(), dest.guard(), key, typename maker::template less_wrapper<Less>::type() );
+ CDS_UNUSED( pred );
+ guarded_ptr gp;
+ extract_at( head(), gp.guard(), key, typename maker::template less_wrapper<Less>::type() );
+ return gp;
}
- /// Finds \p key
- /** \anchor cds_nonintrusive_MichaelList_hp_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
+ and returns \p true if it is found, and \p false otherwise.
*/
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 \p key 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_hp_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
+ template <typename Q, typename Less>
+ CDS_DEPRECATED("deprecated, use contains()")
+ bool find_with( Q const& key, Less pred )
+ {
+ return contains( key, pred );
+ }
+ //@endcond
/// Finds \p key and perform an action with it
/** \anchor cds_nonintrusive_MichaelList_hp_find_func
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 \p key and return the item found
/** \anchor cds_nonintrusive_MichaelList_hp_get
The function searches the item with key equal to \p key
- and assigns the item found to guarded pointer \p ptr.
- The function returns \p true if \p key is found, and \p false otherwise.
- If \p key is not found the \p ptr parameter is not changed.
+ and returns it as \p guarded_ptr.
+ If \p key is not found the function returns an empty guarded pointer.
@note Each \p guarded_ptr object uses one GC's guard which can be limited resource.
ord_list theList;
// ...
{
- ord_list::guarded_ptr gp;
- if ( theList.get( gp, 5 )) {
+ ord_list::guarded_ptr gp(theList.get( 5 ));
+ if ( gp ) {
// Deal with gp
//...
}
should accept a parameter of type \p Q that can be not the same as \p value_type.
*/
template <typename Q>
- bool get( guarded_ptr& ptr, Q const& key )
+ guarded_ptr get( Q const& key )
{
- return get_at( head(), ptr.guard(), key, intrusive_key_comparator() );
+ guarded_ptr gp;
+ get_at( head(), gp.guard(), key, intrusive_key_comparator() );
+ return gp;
}
/// Finds \p key and return the item found
/**
- The function is an analog of \ref cds_nonintrusive_MichaelList_hp_get "get( guarded_ptr& ptr, Q const&)"
+ The function is an analog of \ref cds_nonintrusive_MichaelList_hp_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 accept arguments of type \p value_type and \p Q
\p pred must imply the same element order as the comparator used for building the list.
*/
template <typename Q, typename Less>
- bool get_with( guarded_ptr& ptr, Q const& key, Less pred )
+ guarded_ptr get_with( Q const& key, Less pred )
{
- return get_at( head(), ptr.guard(), key, typename maker::template less_wrapper<Less>::type() );
+ CDS_UNUSED( pred );
+ guarded_ptr gp;
+ get_at( head(), gp.guard(), key, typename maker::template less_wrapper<Less>::type() );
+ return gp;
}
/// Check if the list is empty
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 Compare>
- bool extract_at( head_type& refHead, typename gc::Guard& dest, Q const& key, Compare cmp )
+ bool extract_at( head_type& refHead, typename guarded_ptr::native_guard& guard, Q const& key, Compare cmp )
{
- return base_class::extract_at( refHead, dest, key, cmp );
+ return base_class::extract_at( refHead, guard, key, cmp );
}
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>
- bool get_at( head_type& refHead, typename gc::Guard& guard, Q const& key, Compare cmp )
+ bool get_at( head_type& refHead, typename guarded_ptr::native_guard& guard, Q const& key, Compare cmp )
{
return base_class::get_at( refHead, guard, key, cmp );
}
}} // namespace cds::container
-#endif // #ifndef __CDS_CONTAINER_IMPL_MICHAEL_LIST_H
+#endif // #ifndef CDSLIB_CONTAINER_IMPL_MICHAEL_LIST_H
projects / libcds.git / blobdiff