cds  2.2.0
cds::container::SplitListMap< GC, Key, Value, Traits > Class Template Reference

Split-ordered list map. More...

#include <cds/container/split_list_map.h>

Inheritance diagram for cds::container::SplitListMap< GC, Key, Value, Traits >:
cds::container::SplitListSet< GC, std::pair< Key const, Value >, split_list::details::wrap_map_traits< Key, Value, Traits > > cds::intrusive::SplitListSet< GC, split_list::details::wrap_map_traits< Key, Value, Traits > ::ordered_list, split_list::details::wrap_map_traits< Key, Value, Traits > >

Public Types

typedef GC 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_typevalue_type
 key-value pair type
 
typedef base_class::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 key_type.
 
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

 SplitListMap ()
 Initializes split-ordered map of default capacity. More...
 
 SplitListMap (size_t nItemCount, size_t nLoadFactor=1)
 Initializes split-ordered map. More...
 
template<typename K >
bool insert (K &&key)
 Inserts new node with key and default value. More...
 
template<typename K , typename V >
bool insert (K &&key, V &&val)
 Inserts new node. More...
 
template<typename K , typename Func >
bool insert_with (K &&key, Func func)
 Inserts new node and initialize it by a functor. More...
 
template<typename K , typename... Args>
bool emplace (K &&key, Args &&... args)
 For key key inserts data of type mapped_type created from args. More...
 
template<typename K , typename Func >
std::enable_if< std::is_same< K, K >::value &&!is_iterable_list< ordered_list >::value, std::pair< bool, bool > >::type update (K &&key, Func func, bool bAllowInsert=true)
 Updates the node. More...
 
template<typename Q , typename V >
std::pair< bool, bool > upsert (Q &&key, V &&val, bool bAllowInsert=true)
 Inserts or updates the node (only for IterableKVList) More...
 
template<typename K >
bool erase (K const &key)
 Deletes key from the map. More...
 
template<typename K , typename Less >
bool erase_with (K const &key, Less pred)
 Deletes the item from the map using pred predicate for searching. More...
 
template<typename K , typename Func >
bool erase (K const &key, Func f)
 Deletes key from the map. More...
 
template<typename K , typename Less , typename Func >
bool erase_with (K const &key, Less pred, Func f)
 Deletes the item from the map using pred predicate for searching. More...
 
template<typename K >
guarded_ptr extract (K const &key)
 Extracts the item with specified key. More...
 
template<typename K , typename Less >
guarded_ptr extract_with (K const &key, Less pred)
 Extracts the item using compare functor pred. More...
 
template<typename K , typename Func >
bool find (K const &key, Func f)
 Finds the key key. More...
 
template<typename K >
iterator find (K const &key)
 Finds key and returns iterator pointed to the item found (only for IterableList) More...
 
template<typename K , typename Less , typename Func >
bool find_with (K const &key, Less pred, Func f)
 Finds the key val using pred predicate for searching. More...
 
template<typename K , typename Less >
iterator find_with (K const &key, Less pred)
 Finds key using pred predicate and returns iterator pointed to the item found (only for IterableList) More...
 
template<typename K >
bool contains (K const &key)
 Checks whether the map contains key. More...
 
template<typename K , typename Less >
bool contains (K const &key, Less pred)
 Checks whether the map contains key using pred predicate for searching. More...
 
template<typename K >
guarded_ptr get (K const &key)
 Finds key and return the item found. More...
 
template<typename K , typename Less >
guarded_ptr get_with (K const &key, Less pred)
 Finds key and return the item found. More...
 
void clear ()
 Clears the map (not atomic)
 
bool empty () const
 Checks if the map is empty. More...
 
size_t size () const
 Returns item count in the map.
 
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 base_class::iterator iterator
 Forward iterator. More...
 
typedef base_class::const_iterator const_iterator
 Const forward iterator.
 
iterator begin ()
 Returns a forward iterator addressing the first element in a map. More...
 
iterator end ()
 Returns an iterator that addresses the location succeeding the last element in a map. More...
 
const_iterator begin () const
 Returns a forward const iterator addressing the first element in a map.
 
const_iterator cbegin () const
 Returns a forward const iterator addressing the first element in a map.
 
const_iterator end () const
 Returns an const iterator that addresses the location succeeding the last element in a map.
 
const_iterator cend () const
 Returns an const iterator that addresses the location succeeding the last element in a map.
 

Additional Inherited Members

- Protected Types inherited from cds::container::SplitListSet< GC, std::pair< Key const, Value >, split_list::details::wrap_map_traits< Key, Value, Traits > >
typedef GC gc
 Garbage collector.
 
typedef std::pair< Key const, Value > value_type
 Type of vlue to be stored in split-list.
 
typedef split_list::details::wrap_map_traits< Key, Value, 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.
 
typedef iterator_type< false > iterator
 Forward iterator. More...
 
typedef iterator_type< true > const_iterator
 Const forward iterator.
 
- Protected Types inherited from cds::intrusive::SplitListSet< GC, split_list::details::wrap_map_traits< Key, Value, Traits > ::ordered_list, split_list::details::wrap_map_traits< Key, Value, Traits > >
typedef GC gc
 Garbage collector.
 
typedef split_list::details::wrap_map_traits< Key, Value, Traits > traits
 Set traits.
 
typedef split_list::details::wrap_map_traits< Key, Value, 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::container::SplitListSet< GC, std::pair< Key const, Value >, split_list::details::wrap_map_traits< Key, Value, Traits > >
 SplitListSet ()
 Initializes split-ordered list of default capacity. More...
 
 SplitListSet (size_t nItemCount, size_t nLoadFactor=1)
 Initializes split-ordered list. More...
 
bool insert (Q &&val)
 Inserts new node. More...
 
bool insert (Q &&val, Func f)
 Inserts new node. More...
 
bool emplace (Args &&... args)
 Inserts data of type value_type created from args. More...
 
std::pair< bool, bool > upsert (Q &&val, bool bAllowInsert=true)
 Inserts or updates the node (only for IterableList -based set) More...
 
std::pair< bool, bool > update (Q &&val, Func func, bool bAllowInsert=true)
 Updates the node. More...
 
bool erase (Q const &key)
 Deletes key from the set. More...
 
bool erase (Q const &key, Func f)
 Deletes key from the set. More...
 
bool erase_with (Q const &key, Less pred)
 Deletes the item from the set using pred predicate for searching. More...
 
bool erase_with (Q const &key, Less pred, Func f)
 Deletes the item from the set using pred predicate for searching. 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 -based set) More...
 
bool find_with (Q &key, Less pred, Func f)
 Finds the key key using pred predicate for searching. More...
 
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...
 
bool contains (Q const &key)
 Checks whether the set contains key. More...
 
bool contains (Q const &key, Less pred)
 Checks whether the map 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 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.
 
iterator begin ()
 Returns a forward iterator addressing the first element in a set. More...
 
const_iterator begin () const
 Returns a forward const iterator addressing the first element in a set.
 
iterator end ()
 Returns an iterator that addresses the location succeeding the last element in a set. More...
 
const_iterator end () const
 Returns an const iterator that addresses the location succeeding the last element in a set.
 
const_iterator cbegin () const
 Returns a forward const iterator addressing the first element in a set.
 
const_iterator cend () const
 Returns an const iterator that addresses the location succeeding the last element in a set.
 
- Protected Member Functions inherited from cds::intrusive::SplitListSet< GC, split_list::details::wrap_map_traits< Key, Value, Traits > ::ordered_list, split_list::details::wrap_map_traits< Key, Value, 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.
 
split_list::details::wrap_map_traits< Key, Value, 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::container::SplitListSet< GC, std::pair< Key const, Value >, split_list::details::wrap_map_traits< Key, Value, Traits > >
static constexpr const size_t c_nHazardPtrCount
 Count of hazard pointer required.
 
- Static Protected Attributes inherited from cds::intrusive::SplitListSet< GC, split_list::details::wrap_map_traits< Key, Value, Traits > ::ordered_list, split_list::details::wrap_map_traits< Key, Value, Traits > >
static constexpr const size_t c_nHazardPtrCount
 Count of hazard pointer required.
 

Detailed Description

template<class GC, typename Key, typename Value, class Traits = split_list::traits>
class cds::container::SplitListMap< GC, Key, Value, Traits >

Split-ordered list map.

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:

  • GC - Garbage collector used like cds::gc::HP or cds::gc::DHP
  • Key - key type of an item stored in the map. It should be copy-constructible
  • Value - value type stored in the map
  • Traits - map traits, default is split_list::traits. Instead of declaring split_list::traits -based struct you may apply option-based notation with split_list::make_traits metafunction.

There are the specializations:

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 gc::HP GC and MichaelList as ordered list implementation. Your map should map int key to std::string value. So, you beginning your code with the following:

#include <cds/container/michael_list_hp.h>
#include <cds/container/split_list_map.h>
namespace cc = cds::container;

The inclusion order is important: first, include file for ordered-list implementation (for this example, cds/container/michael_list_hp.h), then the header for split-list map cds/container/split_list_map.h.

Now, you should declare traits for split-list map. The main parts of traits are a hash functor and a comparing functor for the ordered list. We use std::hash<int> as hash functor and std::less<int> predicate as comparing functor.

The second attention: instead of using MichaelList in SplitListMap traits we use a tag cds::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.

// 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
};
};

Now you are ready to declare our map class based on SplitListMap:

typedef cc::SplitListMap< cds::gc::DHP, int, std::string, foo_set_traits > int_string_map;

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

typedef cc::SplitListMap<
cs::gc::DHP // GC used
,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;

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

Now, the map of type int_string_map 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 container::split_list::traits. There are many other options for deep tuning of the split-list and ordered-list containers.

Member Typedef Documentation

§ iterator

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
typedef base_class::iterator cds::container::SplitListMap< GC, Key, Value, 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

§ SplitListMap() [1/2]

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
cds::container::SplitListMap< GC, Key, Value, Traits >::SplitListMap ( )
inline

Initializes split-ordered map 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 intrusive::split_list::traits::dynamic_bucket_table.

§ SplitListMap() [2/2]

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
cds::container::SplitListMap< GC, Key, Value, Traits >::SplitListMap ( size_t  nItemCount,
size_t  nLoadFactor = 1 
)
inline

Initializes split-ordered map.

Parameters
nItemCountestimated average item count
nLoadFactorload factor - average item count per bucket. Small integer up to 10, default is 1.

Member Function Documentation

§ begin()

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
iterator cds::container::SplitListMap< GC, Key, Value, Traits >::begin ( )
inline

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

For empty map

begin() == end()

§ contains() [1/2]

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K >
bool cds::container::SplitListMap< GC, Key, Value, Traits >::contains ( K const &  key)
inline

Checks whether the map 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 , typename Key , typename Value , class Traits = split_list::traits>
template<typename K , typename Less >
bool cds::container::SplitListMap< GC, Key, Value, Traits >::contains ( K 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 , typename Key , typename Value , class Traits = split_list::traits>
template<typename K , typename... Args>
bool cds::container::SplitListMap< GC, Key, Value, Traits >::emplace ( K &&  key,
Args &&...  args 
)
inline

For key key inserts data of type mapped_type created from args.

key_type should be constructible from type K

Returns true if inserting successful, false otherwise.

§ empty()

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
bool cds::container::SplitListMap< GC, Key, Value, Traits >::empty ( ) const
inline

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.

§ end()

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
iterator cds::container::SplitListMap< GC, Key, Value, Traits >::end ( )
inline

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

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 map. For empty map

begin() == end()

§ erase() [1/2]

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K >
bool cds::container::SplitListMap< GC, Key, Value, Traits >::erase ( K const &  key)
inline

Deletes key from the map.

Return true if key is found and deleted, false otherwise

§ erase() [2/2]

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K , typename Func >
bool cds::container::SplitListMap< GC, Key, Value, Traits >::erase ( K const &  key,
Func  f 
)
inline

Deletes key from the map.

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 is:

struct extractor {
void operator()(value_type& item) { ... }
};

Return true if key is found and deleted, false otherwise

§ erase_with() [1/2]

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K , typename Less >
bool cds::container::SplitListMap< GC, Key, Value, Traits >::erase_with ( K const &  key,
Less  pred 
)
inline

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

The function is an analog of erase(K 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 map.

§ erase_with() [2/2]

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K , typename Less , typename Func >
bool cds::container::SplitListMap< GC, Key, Value, Traits >::erase_with ( K const &  key,
Less  pred,
Func  f 
)
inline

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

The function is an analog of erase(K 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 map.

§ extract()

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K >
guarded_ptr cds::container::SplitListMap< GC, Key, Value, Traits >::extract ( K const &  key)
inline

Extracts the item with specified key.

The function searches an item with key equal to key, unlinks it from the map, 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 K 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_map theMap;
// ...
{
splitlist_map::guarded_ptr gp(theMap.extract( 5 ));
if ( gp ) {
// Deal with gp
// ...
}
// Destructor of gp releases internal HP guard
}

§ extract_with()

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K , typename Less >
guarded_ptr cds::container::SplitListMap< GC, Key, Value, Traits >::extract_with ( K const &  key,
Less  pred 
)
inline

Extracts the item using compare functor pred.

The function is an analog of extract(K 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 K in any order. pred must imply the same element order as the comparator used for building the map.

§ find() [1/2]

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K , typename Func >
bool cds::container::SplitListMap< GC, Key, Value, Traits >::find ( K const &  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 );
};

where item is the item found.

The functor may change item.second. 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 map's item. If such access is possible you must provide your own synchronization schema on item level to exclude unsafe item modifications.

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

§ find() [2/2]

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K >
iterator cds::container::SplitListMap< GC, Key, Value, Traits >::find ( K const &  key)
inline

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

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

Note
This function is supported only for map based on IterableList

§ find_with() [1/2]

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K , typename Less , typename Func >
bool cds::container::SplitListMap< GC, Key, Value, Traits >::find_with ( K const &  key,
Less  pred,
Func  f 
)
inline

Finds the key val using pred predicate for searching.

The function is an analog of find(K 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 map.

§ find_with() [2/2]

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K , typename Less >
iterator cds::container::SplitListMap< GC, Key, Value, Traits >::find_with ( K const &  key,
Less  pred 
)
inline

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

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

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

Note
This function is supported only for map based on IterableList

§ get()

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K >
guarded_ptr cds::container::SplitListMap< GC, Key, Value, Traits >::get ( K const &  key)
inline

Finds key and return the item found.

The function searches the item with key equal to key and returns the item found as a guarded pointer. 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_map theMap;
// ...
{
splitlist_map::guarded_ptr gp(theMap.get( 5 ));
if ( gp ) {
// Deal with gp
//...
}
// Destructor of guarded_ptr releases internal HP guard
}

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

§ get_with()

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K , typename Less >
guarded_ptr cds::container::SplitListMap< GC, Key, Value, Traits >::get_with ( K const &  key,
Less  pred 
)
inline

Finds key and return the item found.

The function is an analog of get( K 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 K in any order. pred must imply the same element order as the comparator used for building the map.

§ insert() [1/2]

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K >
bool cds::container::SplitListMap< GC, Key, Value, Traits >::insert ( K &&  key)
inline

Inserts new node with key and default value.

The function creates a node with key and default value, and then inserts the node created into the map.

Preconditions:

  • The key_type should be constructible from value of type K. In trivial case, K is equal to key_type.
  • The mapped_type should be default-constructible.

Returns true if inserting successful, false otherwise.

§ insert() [2/2]

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K , typename V >
bool cds::container::SplitListMap< GC, Key, Value, Traits >::insert ( K &&  key,
V &&  val 
)
inline

Inserts new node.

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

Preconditions:

  • The key_type should be constructible from key of type K.
  • The mapped_type should be constructible from val of type V.

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

§ insert_with()

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K , typename Func >
bool cds::container::SplitListMap< GC, Key, Value, Traits >::insert_with ( K &&  key,
Func  func 
)
inline

Inserts new node and initialize it by a functor.

This function inserts new node with key key and if inserting is successful then it calls func functor with signature

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

The argument item of user-defined functor func is the reference to the map's item inserted:

  • item.first is a const reference to item's key that cannot be changed.
  • item.second is a reference to item's value that may be changed.

It should be keep in mind that concurrent modifications of item.second may be possible.

The key_type should be constructible from value of type K.

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

  • create item from key;
  • insert new item into the map;
  • if inserting is successful, initialize the value of item by calling func functor

This can be useful if complete initialization of object of mapped_type is heavyweight and it is preferable that the initialization should be completed only if inserting is successful.

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

§ update()

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename K , typename Func >
std::enable_if< std::is_same<K,K>::value && !is_iterable_list< ordered_list >::value, std::pair<bool, bool> >::type cds::container::SplitListMap< GC, Key, Value, Traits >::update ( K &&  key,
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 map, then key is inserted iff bAllowInsert is true. Otherwise, the functor func is called with item found.

The functor func signature depends on ordered list:

for MichaelKVList, LazyKVList

struct my_functor {
void operator()( bool bNew, value_type& item );
};

with arguments:

  • bNew - true if the item has been inserted, false otherwise
  • item - the item found or inserted

The functor may change any fields of the item.second that is mapped_type.

for IterableKVList

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 map.

Warning
For MichaelKVList and IterableKVList as the ordered list see insert item troubleshooting. LazyKVList provides exclusive access to inserted item and does not require any node-level synchronization.

§ upsert()

template<class GC , typename Key , typename Value , class Traits = split_list::traits>
template<typename Q , typename V >
std::pair<bool, bool> cds::container::SplitListMap< GC, Key, Value, Traits >::upsert ( Q &&  key,
V &&  val,
bool  bAllowInsert = true 
)
inline

Inserts or updates the node (only for IterableKVList)

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

If key is not found in the map, then key 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 map.


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