cds  2.2.0
cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits > Class Template Reference

Lock-free skip-list map (template specialization for gc::nogc) More...

#include <cds/container/skip_list_map_nogc.h>

Inheritance diagram for cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >:
cds::container::SkipListSet< cds::gc::nogc, std::pair< Key const, T >, Traits > cds::intrusive::SkipListSet< cds::gc::nogc, std::pair< Key const, T >, Traits >

Public Types

typedef cds::gc::nogc gc
 Garbage collector.
 
typedef Key key_type
 Key type.
 
typedef T mapped_type
 Mapped type.
 
typedef std::pair< key_type const, mapped_typevalue_type
 Key-value pair stored in the map.
 
typedef Traits traits
 Options specified.
 
typedef base_class::back_off back_off
 Back-off strategy.
 
typedef base_class::allocator_type allocator_type
 Allocator type used for allocate/deallocate the skip-list nodes.
 
typedef base_class::item_counter item_counter
 Item counting policy.
 
typedef base_class::key_comparator key_comparator
 key compare functor
 
typedef base_class::memory_model memory_model
 Memory ordering, see cds::opt::memory_model option.
 
typedef base_class::stat stat
 internal statistics type
 
typedef base_class::random_level_generator random_level_generator
 random level generator
 

Public Member Functions

 SkipListMap ()
 Default constructor.
 
 ~SkipListMap ()
 Destructor clears the map.
 
template<typename K >
iterator insert (K const &key)
 Inserts new node with key and default value. More...
 
template<typename K , typename V >
iterator insert (K const &key, V const &val)
 Inserts new node. More...
 
template<typename K , typename Func >
iterator insert_with (K const &key, Func func)
 Inserts new node and initialize it by a functor. More...
 
template<typename K , typename... Args>
iterator emplace (K &&key, Args &&... args)
 For key key inserts data of type mapped_type created in-place from args. More...
 
template<typename K >
std::pair< iterator, bool > update (K const &key, bool bInsert=true)
 UPdates data by key. More...
 
template<typename K >
iterator contains (K const &key)
 Checks whether the map contains key. More...
 
template<typename K , typename Less >
iterator contains (K const &key, Less pred) const
 Checks whether the map contains key using pred predicate for searching. More...
 
value_typeget_min () const
 Gets minimum key from the map. More...
 
value_typeget_max () const
 Gets maximum key from the map. More...
 
void clear ()
 Clears the map (not atomic) More...
 
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 const reference to internal statistics.
 

Static Public Member Functions

static constexpr unsigned int max_height () noexcept()
 Returns maximum height of skip-list. The max height is a constant for each object and does not exceed 32.
 

Forward ordered iterators

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::SkipListSet< cds::gc::nogc, std::pair< Key const, T >, Traits >
typedef cds::gc::nogc gc
 Garbage collector used.
 
typedef std::pair< Key const, T > value_type
 
typedef Traits traits
 Options specified.
 
typedef base_class::back_off back_off
 Back-off strategy.
 
typedef traits::allocator allocator_type
 Allocator type used for allocate/deallocate the skip-list nodes.
 
typedef base_class::item_counter item_counter
 Item counting policy used.
 
typedef maker::key_comparator key_comparator
 key comparison functor
 
typedef base_class::memory_model memory_model
 Memory ordering. See cds::opt::memory_model option.
 
typedef traits::random_level_generator random_level_generator
 random level generator
 
typedef traits::stat stat
 internal statistics type
 
typedef gc::template guarded_ptr< node_type, value_type, details::guarded_ptr_cast_set< node_type, value_type > > guarded_ptr
 Guarded pointer.
 
typedef skip_list::details::iterator< typename base_class::iterator > iterator
 Iterator type. More...
 
typedef skip_list::details::iterator< typename base_class::const_iterator > const_iterator
 Const iterator type.
 
- Protected Types inherited from cds::intrusive::SkipListSet< cds::gc::nogc, std::pair< Key const, T >, Traits >
typedef node_type::atomic_marked_ptr atomic_node_ptr
 Atomic marked node pointer.
 
typedef node_type::marked_ptr marked_node_ptr
 Node marked pointer.
 
typedef cds::gc::nogc gc
 Garbage collector.
 
typedef std::pair< Key const, T > value_type
 type of value stored in the skip-list
 
typedef Traits traits
 Traits template parameter.
 
typedef traits::hook hook
 hook type
 
typedef hook::node_type node_type
 node type
 
typedef implementation_defined key_comparator
 key comparison functor based on opt::compare and opt::less option setter.
 
typedef traits::disposer disposer
 item disposer
 
typedef get_node_traits< value_type, node_type, hook >::type node_traits
 node traits
 
typedef traits::item_counter item_counter
 Item counting policy.
 
typedef traits::memory_model memory_model
 Memory ordering, see cds::opt::memory_model option.
 
typedef traits::random_level_generator random_level_generator
 random level generator
 
typedef traits::allocator allocator_type
 allocator for maintaining array of next pointers of the node
 
typedef traits::back_off back_off
 Back-off strategy.
 
typedef traits::stat stat
 internal statistics type
 
typedef gc::template guarded_ptr< value_typeguarded_ptr
 Guarded pointer.
 
typedef skip_list::details::iterator< gc, node_traits, back_off, false > iterator
 Iterator type. More...
 
typedef skip_list::details::iterator< gc, node_traits, back_off, true > const_iterator
 Const iterator type.
 
- Protected Member Functions inherited from cds::container::SkipListSet< cds::gc::nogc, std::pair< Key const, T >, Traits >
 SkipListSet ()
 Default ctor.
 
 ~SkipListSet ()
 Destructor destroys the set object.
 
bool insert (Q const &val)
 Inserts new node. More...
 
bool insert (Q const &val, Func f)
 Inserts new node. More...
 
std::pair< bool, bool > update (const Q &val, Func func, bool bInsert=true)
 Updates the item. More...
 
bool emplace (Args &&... args)
 Inserts data of type value_type created in-place from std::forward<Args>(args)... More...
 
bool erase (Q const &key)
 Delete key from the set. More...
 
bool erase (Q const &key, Func f)
 Delete 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 from the set with specified key. More...
 
guarded_ptr extract_with (Q const &key, Less pred)
 Extracts the item from the set with comparing functor pred. More...
 
guarded_ptr extract_min ()
 Extracts an item with minimal key from the set. More...
 
guarded_ptr extract_max ()
 Extracts an item with maximal key from the set. More...
 
bool find (Q &key, Func f)
 Find the key. More...
 
bool find_with (Q &key, Less pred, Func f)
 Finds key using pred predicate for searching. 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 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). More...
 
bool empty () const
 Checks if the set is empty.
 
size_t size () const
 Returns item count in the set. More...
 
stat const & statistics () const
 Returns const reference to internal statistics.
 
iterator begin ()
 Returns a forward iterator addressing the first element in a set.
 
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.
 
iterator end ()
 Returns a forward iterator that addresses the location succeeding the last element in a set.
 
const_iterator end () const
 Returns a forward const iterator that addresses the location succeeding the last element in a set.
 
const_iterator cend () const
 Returns a forward const iterator that addresses the location succeeding the last element in a set.
 
- Protected Member Functions inherited from cds::intrusive::SkipListSet< cds::gc::nogc, std::pair< Key const, T >, Traits >
 SkipListSet ()
 Default constructor. More...
 
 ~SkipListSet ()
 Clears and destructs the skip-list.
 
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 bInsert=true)
 Updates the node. More...
 
bool unlink (value_type &val)
 Unlinks the item val from the set. More...
 
guarded_ptr extract (Q const &key)
 Extracts the item from the set with specified key. More...
 
guarded_ptr extract_with (Q const &key, Less pred)
 Extracts the item from the set with comparing functor pred. More...
 
guarded_ptr extract_min ()
 Extracts an item with minimal key from the list. More...
 
guarded_ptr extract_max ()
 Extracts an item with maximal key from the list. 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 (Q const &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...
 
bool find (Q &key, Func f)
 Finds key. More...
 
bool find_with (Q &key, Less pred, Func f)
 Finds the key key with pred predicate for comparing. 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 key and return the item found. More...
 
guarded_ptr get_with (Q const &key, Less pred)
 Finds key and return the item found. More...
 
size_t size () const
 Returns item count in the set. More...
 
bool empty () const
 Checks if the set is empty.
 
void clear ()
 Clears the set (not atomic) More...
 
stat const & statistics () const
 Returns const reference to internal statistics.
 
iterator begin ()
 Returns a forward iterator addressing the first element in a set.
 
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.
 
iterator end ()
 Returns a forward iterator that addresses the location succeeding the last element in a set.
 
const_iterator end () const
 Returns a forward const iterator that addresses the location succeeding the last element in a set.
 
const_iterator cend () const
 Returns a forward const iterator that addresses the location succeeding the last element in a set.
 
- Static Protected Member Functions inherited from cds::intrusive::SkipListSet< cds::gc::nogc, std::pair< Key const, T >, Traits >
static constexpr unsigned int max_height () noexcept()
 Returns maximum height of skip-list. The max height is a constant for each object and does not exceed 32.
 
- Static Protected Attributes inherited from cds::container::SkipListSet< cds::gc::nogc, std::pair< Key const, T >, Traits >
static size_t const c_nHazardPtrCount
 Count of hazard pointer required for the skip-list.
 
- Static Protected Attributes inherited from cds::intrusive::SkipListSet< cds::gc::nogc, std::pair< Key const, T >, Traits >
static unsigned int const c_nMaxHeight
 Max node height. The actual node height should be in range [0 .. c_nMaxHeight) More...
 
static size_t const c_nHazardPtrCount
 Count of hazard pointer required for the skip-list.
 

Detailed Description

template<typename Key, typename T, typename Traits = skip_list::traits>
class cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >

Lock-free skip-list map (template specialization for gc::nogc)

This specialization is intended for so-called persistent usage when no item reclamation may be performed. The class does not support deleting of map item. See SkipListMap for detailed description.

Template arguments:

  • K - type of a key to be stored in the map.
  • T - type of a value to be stored in the map.
  • Traits - map traits, default is skip_list::traits It is possible to declare option-based list with cds::container::skip_list::make_traits metafunction istead of Traits template argument.

Member Typedef Documentation

§ iterator

template<typename Key , typename T , typename Traits = skip_list::traits>
typedef base_class::iterator cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >::iterator

Forward iterator.

The forward iterator for a split-list has some features:

  • it has no post-increment operator
  • it depends on iterator of underlying OrderedList

Member Function Documentation

§ begin()

template<typename Key , typename T , typename Traits = skip_list::traits>
iterator cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >::begin ( )
inline

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

For empty set

begin() == end()

§ clear()

template<typename Key , typename T , typename Traits = skip_list::traits>
void cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >::clear ( )
inline

Clears the map (not atomic)

Finding and/or inserting is prohibited while clearing. Otherwise an unpredictable result may be encountered. Thus, clear() may be used only for debugging purposes.

§ contains() [1/2]

template<typename Key , typename T , typename Traits = skip_list::traits>
template<typename K >
iterator cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >::contains ( K const &  key)
inline

Checks whether the map contains key.

The function searches the item with key equal to key and returns an iterator pointed to item found if the key is found, and end() otherwise

§ contains() [2/2]

template<typename Key , typename T , typename Traits = skip_list::traits>
template<typename K , typename Less >
iterator cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >::contains ( K const &  key,
Less  pred 
) const
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<typename Key , typename T , typename Traits = skip_list::traits>
template<typename K , typename... Args>
iterator cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >::emplace ( K &&  key,
Args &&...  args 
)
inline

For key key inserts data of type mapped_type created in-place from args.

key_type should be constructible from type K

Returns true if inserting successful, false otherwise.

§ empty()

template<typename Key , typename T , typename Traits = skip_list::traits>
bool cds::container::SkipListMap< cds::gc::nogc, Key, T, 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 feature is an important part of Michael's map implementation.

§ end()

template<typename Key , typename T , typename Traits = skip_list::traits>
iterator cds::container::SkipListMap< cds::gc::nogc, Key, T, 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 set. For empty set

begin() == end()

§ get_max()

template<typename Key , typename T , typename Traits = skip_list::traits>
value_type* cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >::get_max ( ) const
inline

Gets maximum key from the map.

The function returns nullptr if the map is empty

§ get_min()

template<typename Key , typename T , typename Traits = skip_list::traits>
value_type* cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >::get_min ( ) const
inline

Gets minimum key from the map.

If the map is empty the function returns nullptr

§ insert() [1/2]

template<typename Key , typename T , typename Traits = skip_list::traits>
template<typename K >
iterator cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >::insert ( K const &  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 an iterator pointed to inserted value, or end() if inserting is failed

§ insert() [2/2]

template<typename Key , typename T , typename Traits = skip_list::traits>
template<typename K , typename V >
iterator cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >::insert ( K const &  key,
V const &  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 an iterator pointed to inserted value, or end() if inserting is failed

§ insert_with()

template<typename Key , typename T , typename Traits = skip_list::traits>
template<typename K , typename Func >
iterator cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >::insert_with ( K const &  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.second is a reference to item's value that may be changed. User-defined functor func should guarantee that during changing item's value no any other changes could be made on this map's item by concurrent threads.

The key_type should be constructible from value of type K.

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

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

Returns an iterator pointed to inserted value, or end() if inserting is failed

§ update()

template<typename Key , typename T , typename Traits = skip_list::traits>
template<typename K >
std::pair<iterator, bool> cds::container::SkipListMap< cds::gc::nogc, Key, T, Traits >::update ( K const &  key,
bool  bInsert = true 
)
inline

UPdates data by key.

The operation inserts new item if key is not found in the map and bInsert is true. Otherwise, if key is found, the function returns an iterator that points to item found.

Returns std::pair<iterator, bool> where first is an iterator pointing to item found or inserted or end() if key is not found and insertion is not allowed (bInsert is false), second is true if new item has been added or false if the item already exists.


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 08:49:41 by Doxygen 1.8.12