cds  2.2.0
cds::container::SplitListSet< GC, T, Traits > Class Template Reference

Split-ordered list set. More...

#include <cds/container/split_list_set.h>

Inheritance diagram for cds::container::SplitListSet< GC, T, Traits >:
cds::intrusive::SplitListSet< GC, Traits::ordered_list, Traits >

Public Types

typedef GC gc
 Garbage collector.
 
typedef T value_type
 Type of vlue to be stored in split-list.
 
typedef Traits traits
 Traits template argument
 
typedef maker::ordered_list ordered_list
 Underlying ordered list class.
 
typedef base_class::key_comparator key_comparator
 key compare functor
 
typedef base_class::hash hash
 Hash functor for value_type and all its derivatives that you use.
 
typedef base_class::item_counter item_counter
 Item counter type.
 
typedef base_class::stat stat
 Internal statistics.
 
typedef gc::template guarded_ptr< node_type, value_type, details::guarded_ptr_cast_set< node_type, value_type > > guarded_ptr
 Guarded pointer.
 

Public Member Functions

 SplitListSet ()
 Initializes split-ordered list of default capacity. More...
 
 SplitListSet (size_t nItemCount, size_t nLoadFactor=1)
 Initializes split-ordered list. More...
 
template<typename Q >
bool insert (Q &&val)
 Inserts new node. More...
 
template<typename Q , typename Func >
bool insert (Q &&val, Func f)
 Inserts new node. More...
 
template<typename... Args>
bool emplace (Args &&... args)
 Inserts data of type value_type created from args. More...
 
template<typename Q >
std::pair< bool, bool > upsert (Q &&val, bool bAllowInsert=true)
 Inserts or updates the node (only for IterableList -based set) More...
 
template<typename Q , typename Func >
std::pair< bool, bool > update (Q &&val, Func func, bool bAllowInsert=true)
 Updates the node. More...
 
template<typename Q >
bool erase (Q const &key)
 Deletes key from the set. More...
 
template<typename Q , typename Less >
bool erase_with (Q const &key, Less pred)
 Deletes the item from the set using pred predicate for searching. More...
 
template<typename Q , typename Func >
bool erase (Q const &key, Func f)
 Deletes key from the set. More...
 
template<typename Q , typename Less , typename Func >
bool erase_with (Q const &key, Less pred, Func f)
 Deletes the item from the set using pred predicate for searching. More...
 
template<typename Q >
guarded_ptr extract (Q const &key)
 Extracts the item with specified key. More...
 
template<typename Q , typename Less >
guarded_ptr extract_with (Q const &key, Less pred)
 Extracts the item using compare functor pred. More...
 
template<typename Q , typename Func >
bool find (Q &key, Func f)
 Finds the key key. More...
 
template<typename Q >
iterator find (Q &key)
 Finds key and returns iterator pointed to the item found (only for IterableList -based set) More...
 
template<typename Q , typename Less , typename Func >
bool find_with (Q &key, Less pred, Func f)
 Finds the key key using pred predicate for searching. More...
 
template<typename Q , typename Less >
iterator find_with (Q &key, Less pred)
 Finds key using pred predicate and returns iterator pointed to the item found (only for IterableList -based set) More...
 
template<typename Q >
bool contains (Q const &key)
 Checks whether the set contains key. More...
 
template<typename Q , typename Less >
bool contains (Q const &key, Less pred)
 Checks whether the map contains key using pred predicate for searching. More...
 
template<typename Q >
guarded_ptr get (Q const &key)
 Finds the key key and return the item found. More...
 
template<typename Q , typename Less >
guarded_ptr get_with (Q const &key, Less pred)
 Finds key and return the item found. More...
 
void clear ()
 Clears the set (not atomic)
 
bool empty () const
 Checks if the set is empty. More...
 
size_t size () const
 Returns item count in the set.
 
stat const & statistics () const
 Returns internal statistics.
 
ordered_list::stat const & list_statistics () const
 Returns internal statistics for ordered_list.
 

Static Public Attributes

static constexpr const size_t c_nHazardPtrCount = base_class::c_nHazardPtrCount
 Count of hazard pointer required.
 

Forward iterators (only for debugging purpose)

typedef iterator_type< false > iterator
 Forward iterator. More...
 
typedef iterator_type< true > const_iterator
 Const forward iterator.
 
iterator begin ()
 Returns a forward iterator addressing the first element in a set. More...
 
iterator end ()
 Returns an iterator that addresses the location succeeding the last element in a set. More...
 
const_iterator begin () const
 Returns a forward const iterator addressing the first element in a set.
 
const_iterator cbegin () const
 Returns a forward const iterator addressing the first element in a set.
 
const_iterator end () const
 Returns an const iterator that addresses the location succeeding the last element in a set.
 
const_iterator cend () const
 Returns an const iterator that addresses the location succeeding the last element in a set.
 

Additional Inherited Members

- Protected Types inherited from cds::intrusive::SplitListSet< GC, Traits::ordered_list, Traits >
typedef GC gc
 Garbage collector.
 
typedef Traits traits
 Set traits.
 
typedef Traits::ordered_list ordered_list
 type of ordered list used as a base for split-list
 
typedef ordered_list::value_type value_type
 type of value stored in the split-list
 
typedef ordered_list::key_comparator key_comparator
 key comparison functor
 
typedef ordered_list::disposer disposer
 Node disposer functor.
 
typedef cds::opt::v::hash_selector< typename traits::hash >::type hash
 Hash functor for value_type and all its derivatives you use.
 
typedef traits::item_counter item_counter
 Item counter type.
 
typedef traits::back_off back_off
 back-off strategy for spinning
 
typedef traits::memory_model memory_model
 Memory ordering. See cds::opt::memory_model option.
 
typedef traits::stat stat
 Internal statistics, see spit_list::stat.
 
typedef ordered_list::guarded_ptr guarded_ptr
 Guarded pointer.
 
typedef iterator_type< false > iterator
 Forward iterator. More...
 
typedef iterator_type< true > const_iterator
 Const forward iterator. More...
 
- Protected Member Functions inherited from cds::intrusive::SplitListSet< GC, Traits::ordered_list, Traits >
 SplitListSet ()
 Initialize split-ordered list of default capacity. More...
 
 SplitListSet (size_t nItemCount, size_t nLoadFactor=1)
 Initialize split-ordered list. More...
 
 ~SplitListSet ()
 Destroys split-list set.
 
bool insert (value_type &val)
 Inserts new node. More...
 
bool insert (value_type &val, Func f)
 Inserts new node. More...
 
std::pair< bool, bool > update (value_type &val, Func func, bool bAllowInsert=true)
 Updates the node. More...
 
std::pair< bool, bool > upsert (value_type &val, bool bAllowInsert=true)
 Inserts or updates the node (only for IterableList) More...
 
bool unlink (value_type &val)
 Unlinks the item val from the set. More...
 
bool erase (Q const &key)
 Deletes the item from the set. More...
 
bool erase (Q const &key, Func f)
 Deletes the item from the set. More...
 
bool erase_with (const Q &key, Less pred)
 Deletes the item from the set with comparing functor pred. More...
 
bool erase_with (Q const &key, Less pred, Func f)
 Deletes the item from the set with comparing functor pred. More...
 
guarded_ptr extract (Q const &key)
 Extracts the item with specified key. More...
 
guarded_ptr extract_with (Q const &key, Less pred)
 Extracts the item using compare functor pred. More...
 
bool find (Q &key, Func f)
 Finds the key key. More...
 
iterator find (Q &key)
 Finds key and returns iterator pointed to the item found (only for IterableList) More...
 
bool find_with (Q &key, Less pred, Func f)
 Finds the key key with pred predicate for comparing. More...
 
iterator find_with (Q &key, Less pred)
 Finds key using pred predicate and returns iterator pointed to the item found (only for IterableList) More...
 
bool contains (Q const &key)
 Checks whether the set contains key. More...
 
bool contains (Q const &key, Less pred)
 Checks whether the set contains key using pred predicate for searching. More...
 
guarded_ptr get (Q const &key)
 Finds the key key and return the item found. More...
 
guarded_ptr get_with (Q const &key, Less pred)
 Finds the key key and return the item found. More...
 
size_t size () const
 Returns item count in the set.
 
bool empty () const
 Checks if the set is empty. More...
 
void clear ()
 Clears the set (non-atomic) More...
 
stat const & statistics () const
 Returns internal statistics.
 
Traits::ordered_list ::stat const & list_statistics () const
 Returns internal statistics for OrderedList.
 
iterator begin ()
 Returns a forward iterator addressing the first element in a split-list. More...
 
const_iterator begin () const
 Returns a forward const iterator addressing the first element in a split-list.
 
iterator end ()
 Returns an iterator that addresses the location succeeding the last element in a split-list. More...
 
const_iterator end () const
 Returns an const iterator that addresses the location succeeding the last element in a split-list.
 
const_iterator cbegin () const
 Returns a forward const iterator addressing the first element in a split-list.
 
const_iterator cend () const
 Returns an const iterator that addresses the location succeeding the last element in a split-list.
 
- Static Protected Attributes inherited from cds::intrusive::SplitListSet< GC, Traits::ordered_list, Traits >
static constexpr const size_t c_nHazardPtrCount
 Count of hazard pointer required.
 

Detailed Description

template<class GC, class T, class Traits = split_list::traits>
class cds::container::SplitListSet< GC, T, Traits >

Split-ordered list set.

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:

There are the specializations:

Usage

You should decide what garbage collector you want, and what ordered list you want to use as a base. Split-ordered list is original data structure based on an ordered list.

Suppose, you want construct split-list set based on gc::DHP GC and LazyList as ordered list implementation. So, you beginning your program with following include:

#include <cds/container/lazy_list_dhp.h>
#include <cds/container/split_list_set.h>
namespace cc = cds::container;
// The data belonged to split-ordered list
sturuct foo {
int nKey; // key field
std::string strValue ; // value field
};

The inclusion order is important: first, include header for ordered-list implementation (for this example, cds/container/lazy_list_dhp.h), then the header for split-list set cds/container/split_list_set.h.

Now, you should declare traits for split-list set. The main parts of traits are a hash functor for the set and a comparing functor for ordered list. Note that we define several function in foo_hash and foo_less functors for different argument types since we want call our SplitListSet object by the key of type int and by the value of type foo.

The second attention: instead of using LazyList in SplitListSet traits we use a tag cds::contaner::lazy_list_tag for the lazy 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.

// foo hash functor
struct foo_hash {
size_t operator()( int key ) const { return std::hash( key ) ; }
size_t operator()( foo const& item ) const { return std::hash( item.nKey ) ; }
};
// foo comparator
struct foo_less {
bool operator()(int i, foo const& f ) const { return i < f.nKey ; }
bool operator()(foo const& f, int i ) const { return f.nKey < i ; }
bool operator()(foo const& f1, foo const& f2) const { return f1.nKey < f2.nKey; }
};
// SplitListSet traits
struct foo_set_traits: public cc::split_list::traits
{
typedef cc::lazy_list_tag ordered_list; // what type of ordered list we want to use
typedef foo_hash hash; // hash functor for our data stored in split-list set
// Type traits for our LazyList class
struct ordered_list_traits: public cc::lazy_list::traits
{
typedef foo_less less ; // use our foo_less as comparator to order list nodes
};
};

Now you are ready to declare our set class based on SplitListSet:

typedef cc::SplitListSet< cds::gc::DHP, foo, foo_set_traits > foo_set;

You may use the modern option-based declaration instead of classic traits-based one:

typedef cc::SplitListSet<
cs::gc::DHP // GC used
,foo // type of data stored
,cc::split_list::make_traits< // metafunction to build split-list traits
cc::split_list::ordered_list<cc::lazy_list_tag> // tag for underlying ordered list implementation
,cc::opt::hash< foo_hash > // hash functor
,cc::split_list::ordered_list_traits< // ordered list traits desired
cc::lazy_list::make_traits< // metafunction to build lazy list traits
cc::opt::less< foo_less > // less-based compare functor
>::type
>
>::type
> foo_set;

In case of option-based declaration using split_list::make_traits metafunction the struct foo_set_traits is not required.

Now, the set of type foo_set is ready to use in your program.

Note that in this example we show only mandatory traits parts, optional ones is the default and they are inherited from cds::container::split_list::traits. There are many other options for deep tuning the split-list and ordered-list containers.

Member Typedef Documentation

§ iterator

template<class GC, class T, class Traits = split_list::traits>
typedef iterator_type<false> cds::container::SplitListSet< GC, T, Traits >::iterator

Forward iterator.

The forward iterator for a split-list has the following features:

  • it has no post-increment operator
  • it depends on underlying ordered list iterator
  • The iterator object cannot be moved across thread boundary because 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 split-list. Moreover, a crash is possible when you try to iterate the next element that has been deleted by concurrent thread.

    Warning
    Use this iterator on the concurrent container for debugging purpose only.

    The iterator interface:

    class iterator {
    public:
    // Default constructor
    // Copy construtor
    iterator( iterator const& src );
    // Dereference operator
    value_type * operator ->() const;
    // Dereference operator
    value_type& operator *() const;
    // Preincrement operator
    iterator& operator ++();
    // Assignment operator
    iterator& operator = (iterator const& src);
    // Equality operators
    bool operator ==(iterator const& i ) const;
    bool operator !=(iterator const& i ) const;
    };

Constructor & Destructor Documentation

§ SplitListSet() [1/2]

template<class GC, class T, class Traits = split_list::traits>
cds::container::SplitListSet< GC, T, Traits >::SplitListSet ( )
inline

Initializes split-ordered list of default capacity.

The default capacity is defined in bucket table constructor. See intrusive::split_list::expandable_bucket_table, intrusive::split_list::static_bucket_table which selects by split_list::dynamic_bucket_table option.

§ SplitListSet() [2/2]

template<class GC, class T, class Traits = split_list::traits>
cds::container::SplitListSet< GC, T, Traits >::SplitListSet ( size_t  nItemCount,
size_t  nLoadFactor = 1 
)
inline

Initializes split-ordered list.

Parameters
nItemCountestimated average of item count
nLoadFactorthe load factor - average item count per bucket. Small integer up to 8, default is 1.

Member Function Documentation

§ begin()

template<class GC, class T, class Traits = split_list::traits>
iterator cds::container::SplitListSet< GC, T, Traits >::begin ( )
inline

Returns a forward iterator addressing the first element in a set.

For empty set

begin() == end()

§ contains() [1/2]

template<class GC, class T, class Traits = split_list::traits>
template<typename Q >
bool cds::container::SplitListSet< GC, T, Traits >::contains ( Q const &  key)
inline

Checks whether the set contains key.

The function searches the item with key equal to key and returns true if it is found, and false otherwise.

Note the hash functor specified for class Traits template parameter should accept a parameter of type Q that can be not the same as value_type. Otherwise, you may use contains( Q const&, Less pred ) functions with explicit predicate for key comparing.

§ contains() [2/2]

template<class GC, class T, class Traits = split_list::traits>
template<typename Q , typename Less >
bool cds::container::SplitListSet< GC, T, Traits >::contains ( Q const &  key,
Less  pred 
)
inline

Checks whether the map contains key using pred predicate for searching.

The function is similar to contains( key ) but pred is used for key comparing. Less functor has the interface like std::less. Less must imply the same element order as the comparator used for building the map.

§ emplace()

template<class GC, class T, class Traits = split_list::traits>
template<typename... Args>
bool cds::container::SplitListSet< GC, T, Traits >::emplace ( Args &&...  args)
inline

Inserts data of type value_type created from args.

Returns true if inserting successful, false otherwise.

§ empty()

template<class GC, class T, class Traits = split_list::traits>
bool cds::container::SplitListSet< GC, T, Traits >::empty ( ) const
inline

Checks if the set is empty.

Emptiness is checked by item counting: if item count is zero then assume that the set is empty. Thus, the correct item counting feature is an important part of split-list set implementation.

§ end()

template<class GC, class T, class Traits = split_list::traits>
iterator cds::container::SplitListSet< GC, T, Traits >::end ( )
inline

Returns an iterator that addresses the location succeeding the last element in a set.

Do not use the value returned by end function to access any item. The returned value can be used only to control reaching the end of the set. For empty set

begin() == end()

§ erase() [1/2]

template<class GC, class T, class Traits = split_list::traits>
template<typename Q >
bool cds::container::SplitListSet< GC, T, Traits >::erase ( Q const &  key)
inline

Deletes key from the set.

The item comparator should be able to compare the values of type value_type and the type Q.

Return true if key is found and deleted, false otherwise

§ erase() [2/2]

template<class GC, class T, class Traits = split_list::traits>
template<typename Q , typename Func >
bool cds::container::SplitListSet< GC, T, Traits >::erase ( Q const &  key,
Func  f 
)
inline

Deletes key from the set.

The function searches an item with key key, calls f functor and deletes the item. If key is not found, the functor is not called.

The functor Func interface:

struct extractor {
void operator()(value_type const& val);
};

Since the key of split-list value_type is not explicitly specified, template parameter Q defines the key type searching in the list. The list item comparator should be able to compare the values of the type value_type and the type Q.

Return true if key is found and deleted, false otherwise

§ erase_with() [1/2]

template<class GC, class T, class Traits = split_list::traits>
template<typename Q , typename Less >
bool cds::container::SplitListSet< GC, T, Traits >::erase_with ( Q const &  key,
Less  pred 
)
inline

Deletes the item from the set using pred predicate for searching.

The function is an analog of erase(Q const&) but pred is used for key comparing. Less functor has the interface like std::less. Less must imply the same element order as the comparator used for building the set.

§ erase_with() [2/2]

template<class GC, class T, class Traits = split_list::traits>
template<typename Q , typename Less , typename Func >
bool cds::container::SplitListSet< GC, T, Traits >::erase_with ( Q const &  key,
Less  pred,
Func  f 
)
inline

Deletes the item from the set using pred predicate for searching.

The function is an analog of erase(Q const&, Func) but pred is used for key comparing. Less functor has the interface like std::less. Less must imply the same element order as the comparator used for building the set.

§ extract()

template<class GC, class T, class Traits = split_list::traits>
template<typename Q >
guarded_ptr cds::container::SplitListSet< GC, T, Traits >::extract ( Q const &  key)
inline

Extracts the item with specified key.

The function searches an item with key equal to key, unlinks it from the set, and returns it as guarded_ptr. If key is not found the function returns an empty guarded pointer.

Note the compare functor should accept a parameter of type Q that may be not the same as value_type.

The extracted item is freed automatically when returned guarded_ptr object will be destroyed or released.

Note
Each guarded_ptr object uses the GC's guard that can be limited resource.

Usage:

splitlist_set theSet;
// ...
{
splitlist_set::guarded_ptr gp(theSet.extract( 5 ));
if ( gp ) {
// Deal with gp
// ...
}
// Destructor of gp releases internal HP guard
}

§ extract_with()

template<class GC, class T, class Traits = split_list::traits>
template<typename Q , typename Less >
guarded_ptr cds::container::SplitListSet< GC, T, Traits >::extract_with ( Q const &  key,
Less  pred 
)
inline

Extracts the item using compare functor pred.

The function is an analog of extract(Q const&) but pred predicate is used for key comparing.

Less functor has the semantics like std::less but should take arguments of type value_type and Q in any order. pred must imply the same element order as the comparator used for building the set.

§ find() [1/2]

template<class GC, class T, class Traits = split_list::traits>
template<typename Q , typename Func >
bool cds::container::SplitListSet< GC, T, Traits >::find ( Q &  key,
Func  f 
)
inline

Finds the key key.

The function searches the item with key equal to key and calls the functor f for item found. The interface of Func functor is:

struct functor {
void operator()( value_type& item, Q& key );
};

where item is the item found, key is the find function argument.

The functor may change non-key fields of item. Note that the functor is only guarantee that item cannot be disposed during functor is executing. The functor does not serialize simultaneous access to the set's item. If such access is possible you must provide your own synchronization schema on item level to exclude unsafe item modifications.

The key argument is non-const since it can be used as f functor destination i.e., the functor may modify both arguments.

Note the hash functor specified for class Traits template parameter should accept a parameter of type Q that can be not the same as value_type.

The function returns true if key is found, false otherwise.

§ find() [2/2]

template<class GC, class T, class Traits = split_list::traits>
template<typename Q >
iterator cds::container::SplitListSet< GC, T, Traits >::find ( Q &  key)
inline

Finds key and returns iterator pointed to the item found (only for IterableList -based set)

If key is not found the function returns end().

Note
This function is supported only for the set based on IterableList

§ find_with() [1/2]

template<class GC, class T, class Traits = split_list::traits>
template<typename Q , typename Less , typename Func >
bool cds::container::SplitListSet< GC, T, Traits >::find_with ( Q &  key,
Less  pred,
Func  f 
)
inline

Finds the key key using pred predicate for searching.

The function is an analog of find(Q&, Func) but pred is used for key comparing. Less functor has the interface like std::less. Less must imply the same element order as the comparator used for building the set.

§ find_with() [2/2]

template<class GC, class T, class Traits = split_list::traits>
template<typename Q , typename Less >
iterator cds::container::SplitListSet< GC, T, Traits >::find_with ( Q &  key,
Less  pred 
)
inline

Finds key using pred predicate and returns iterator pointed to the item found (only for IterableList -based set)

The function is an analog of find(Q&) but pred is used for key comparing. Less functor has the interface like std::less. pred must imply the same element order as the comparator used for building the set.

If key is not found the function returns end().

Note
This function is supported only for the set based on IterableList

§ get()

template<class GC, class T, class Traits = split_list::traits>
template<typename Q >
guarded_ptr cds::container::SplitListSet< GC, T, Traits >::get ( Q const &  key)
inline

Finds the key key and return the item found.

The function searches the item with key equal to key and returns the item found as guarded_ptr. If key is not found the function returns an empty guarded pointer.

Note
Each guarded_ptr object uses one GC's guard which can be limited resource.

Usage:

splitlist_set theSet;
// ...
{
splitlist_set::guarded_ptr gp(theSet.get( 5 ));
if ( gp ) {
// Deal with gp
//...
}
// Destructor of guarded_ptr releases internal HP guard
}

Note the compare functor specified for split-list set should accept a parameter of type Q that can be not the same as value_type.

§ get_with()

template<class GC, class T, class Traits = split_list::traits>
template<typename Q , typename Less >
guarded_ptr cds::container::SplitListSet< GC, T, Traits >::get_with ( Q const &  key,
Less  pred 
)
inline

Finds key and return the item found.

The function is an analog of get( Q const&) but pred is used for comparing the keys.

Less functor has the semantics like std::less but should take arguments of type value_type and Q in any order. pred must imply the same element order as the comparator used for building the set.

§ insert() [1/2]

template<class GC, class T, class Traits = split_list::traits>
template<typename Q >
bool cds::container::SplitListSet< GC, T, Traits >::insert ( Q &&  val)
inline

Inserts new node.

The function creates a node with copy of val value and then inserts the node created into the set.

The type Q should contain as minimum the complete key for the node. The object of value_type should be constructible from a value of type Q. In trivial case, Q is equal to value_type.

Returns true if val is inserted into the set, false otherwise.

§ insert() [2/2]

template<class GC, class T, class Traits = split_list::traits>
template<typename Q , typename Func >
bool cds::container::SplitListSet< GC, T, Traits >::insert ( Q &&  val,
Func  f 
)
inline

Inserts new node.

The function allows to split creating of new item into two part:

  • create item with key only
  • insert new item into the set
  • if inserting is success, calls f functor to initialize value-field of val.

The functor signature is:

void func( value_type& val );

where val is the item inserted.

The user-defined functor is called only if the inserting is success.

Warning
For MichaelList as the bucket see insert item troubleshooting. LazyList provides exclusive access to inserted item and does not require any node-level synchronization.

§ update()

template<class GC, class T, class Traits = split_list::traits>
template<typename Q , typename Func >
std::pair<bool, bool> cds::container::SplitListSet< GC, T, Traits >::update ( Q &&  val,
Func  func,
bool  bAllowInsert = true 
)
inline

Updates the node.

The operation performs inserting or changing data with lock-free manner.

If key is not found in the set, then key is inserted iff bAllowInsert is true. Otherwise, the functor func is called with item found.

The functor func signature depends of ordered list:

for MichaelList, LazyList

struct functor {
void operator()( bool bNew, value_type& item, Q const& val );
};

with arguments:

  • bNew - true if the item has been inserted, false otherwise
  • item - item of the set
  • val - argument val passed into the update() function

The functor may change non-key fields of the item.

for IterableList

void func( value_type& val, value_type * old );

where

  • val - a new data constructed from key
  • old - old value that will be retired. If new item has been inserted then old is nullptr.

Returns std::pair<bool, bool> where first is true if operation is successful, second is true if new item has been added or false if the item with key already is in the set.

Warning
For MichaelList and IterableList as the bucket see insert item troubleshooting. LazyList provides exclusive access to inserted item and does not require any node-level synchronization.

§ upsert()

template<class GC, class T, class Traits = split_list::traits>
template<typename Q >
std::pair<bool, bool> cds::container::SplitListSet< GC, T, Traits >::upsert ( Q &&  val,
bool  bAllowInsert = true 
)
inline

Inserts or updates the node (only for IterableList -based set)

The operation performs inserting or changing data with lock-free manner.

If the item val is not found in the set, then val is inserted iff bAllowInsert is true. Otherwise, the current element is changed to val, the old element will be retired later.

Returns std::pair<bool, bool> where first is true if operation is successful, second is true if val has been added or false if the item with that key already in the set.


The documentation for this class was generated from the following file:

cds 2.2.0 Developed by Maxim Khizhinsky aka khizmax 2007 - 2017
Autogenerated Wed Jan 4 2017 08:49:42 by Doxygen 1.8.12