firebird-mirror/extern/libcds/cds/container/details/ellen_bintree_base.h

// Copyright (c) 2006-2018 Maxim Khizhinsky
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE or copy at http://www.boost.org/LICENSE_1_0.txt)

#ifndef CDSLIB_CONTAINER_DETAILS_ELLEN_BINTREE_BASE_H
#define CDSLIB_CONTAINER_DETAILS_ELLEN_BINTREE_BASE_H

#include <cds/intrusive/details/ellen_bintree_base.h>
#include <cds/container/details/base.h>
#include <cds/opt/compare.h>
#include <cds/details/binary_functor_wrapper.h>


namespace cds { namespace container {
    /// EllenBinTree related definitions
    /** @ingroup cds_nonintrusive_helper
    */
    namespace ellen_bintree {
#ifdef CDS_DOXYGEN_INVOKED
        /// Typedef for \p cds::intrusive::ellen_bintree::update_desc
        typedef cds::intrusive::ellen_bintree::update_desc update_desc;

        /// Typedef for \p cds::intrusive::ellen_bintree::internal_node
        typedef cds::intrusive::ellen_bintree::internal_node internal_node;

        /// Typedef for \p cds::intrusive::ellen_bintree::key_extractor
        typedef cds::intrusive::ellen_bintree::key_extractor key_extractor;

        /// Typedef for \p cds::intrusive::ellen_bintree::update_desc_allocator
        typedef cds::intrusive::ellen_bintree::update_desc_allocator update_desc_allocator;
#else
        using cds::intrusive::ellen_bintree::update_desc;
        using cds::intrusive::ellen_bintree::internal_node;
        using cds::intrusive::ellen_bintree::key_extractor;
        using cds::intrusive::ellen_bintree::update_desc_allocator;
        using cds::intrusive::ellen_bintree::node_types;
#endif
        /// EllenBinTree internal statistics
        template <typename Counter = cds::intrusive::ellen_bintree::stat<>::event_counter >
        using stat = cds::intrusive::ellen_bintree::stat< Counter >;

        /// EllenBinTree empty internal statistics
        typedef cds::intrusive::ellen_bintree::empty_stat empty_stat;

        /// EllenBinTree leaf node
        template <typename GC, typename T>
        struct node: public cds::intrusive::ellen_bintree::node<GC>
        {
            typedef T   value_type  ;   ///< Value type

            T   m_Value ;   ///< Value

            /// Default ctor
            node()
            {}

            /// Initializing ctor
            template <typename Q>
            node(Q const& v)
                : m_Value(v)
            {}

            /// Copy constructor
            template <typename... Args>
            node( Args const&... args )
                : m_Value( args... )
            {}

            /// Move constructor
            template <typename... Args>
            node( Args&&... args )
                : m_Value( std::forward<Args>( args )... )
            {}
        };

        /// EllenBinTreeMap leaf node
        template <typename GC, typename Key, typename T>
        struct map_node: public cds::intrusive::ellen_bintree::node< GC >
        {
            typedef Key     key_type    ;   ///< key type
            typedef T       mapped_type ;   ///< value type
            typedef std::pair<key_type const, mapped_type> value_type  ;   ///< key-value pair stored in the map

            value_type  m_Value     ;   ///< Key-value pair stored in map leaf node

            /// Initializes key field, value if default-constructed
            template <typename K>
            map_node( K const& key )
                : m_Value( std::make_pair( key_type(key), mapped_type()))
            {}

            /// Initializes key and value fields
            template <typename K, typename Q>
            map_node( K const& key, Q const& v )
                : m_Value( std::make_pair(key_type(key), mapped_type(v)))
            {}
        };

        /// Type traits for \p EllenBinTreeSet and \p EllenBinTreeMap
        struct traits
        {
            /// Key extracting functor (only for \p EllenBinTreeSet)
            /**
                This is mandatory functor for \p %EllenBinTreeSet.
                It has the following prototype:
                \code
                struct key_extractor {
                    void operator ()( Key& dest, T const& src );
                };
                \endcode
                It should initialize \p dest key from \p src data.
                The functor is used to initialize internal nodes of \p %EllenBinTreeSet
            */
            typedef opt::none           key_extractor;

            /// Key comparison functor
            /**
                No default functor is provided. If the option is not specified, the \p less is used.

                See \p cds::opt::compare option description for functor interface.

                You should provide \p compare or \p less functor.
                See \ref cds_container_EllenBinTreeSet_rcu_less "predicate requirements".
            */
            typedef opt::none                       compare;

            /// Specifies binary predicate used for key compare.
            /**
                See \p cds::opt::less option description.

                You should provide \p compare or \p less functor.
                See \ref cds_container_EllenBinTreeSet_rcu_less "predicate requirements".
            */
            typedef opt::none                       less;

            /// Item counter
            /**
                The type for item counter, by default it is disabled (\p atomicity::empty_item_counter).
                To enable it use \p atomicity::item_counter or \p atomicity::cache_friendly_item_counter
            */
            typedef atomicity::empty_item_counter     item_counter;

            /// C++ memory ordering model
            /**
                List of available memory ordering see \p opt::memory_model
            */
            typedef opt::v::relaxed_ordering        memory_model;

            /// Allocator for update descriptors
            /**
                The allocator type is used for \p ellen_bintree::update_desc.

                Update descriptor is helping data structure with short lifetime and it is good candidate
                for pooling. The number of simultaneously existing descriptors is a small number
                limited the number of threads working with the tree.
                Therefore, a bounded lock-free container like \p cds::container::VyukovMPMCCycleQueue
                is good choice for the free-list of update descriptors,
                see \p cds::memory::vyukov_queue_pool free-list implementation.

                Also notice that size of update descriptor is not dependent on the type of data
                stored in the tree so single free-list object can be used for several \p EllenBinTree object.
            */
            typedef CDS_DEFAULT_ALLOCATOR           update_desc_allocator;

            /// Allocator for internal nodes
            /**
                The allocator type is used for \p ellen_bintree::internal_node.
            */
            typedef CDS_DEFAULT_ALLOCATOR           node_allocator;

            /// Allocator for leaf nodes
            /**
                Each leaf node contains data stored in the container.
            */
            typedef CDS_DEFAULT_ALLOCATOR           allocator;

            /// Internal statistics
            /**
                By default, internal statistics is disabled (\p ellen_bintree::empty_stat).
                To enable it use \p ellen_bintree::stat.
            */
            typedef empty_stat                      stat;

            /// Back-off strategy
            typedef cds::backoff::empty             back_off;

            /// RCU deadlock checking policy (only for RCU-based EllenBinTree<i>XXX</i> classes)
            /**
                List of available options see \p opt::rcu_check_deadlock
            */
            typedef cds::opt::v::rcu_throw_deadlock      rcu_check_deadlock;

            /// Key copy policy (for \p EllenBinTreeMap)
            /**
                The key copy policy defines a functor to copy leaf node's key to internal node.
                This policy is used only in \p EllenBinTreeMap.
                By default, assignment operator is used.

                The copy functor interface is:
                \code
                struct copy_functor {
                    void operator()( Key& dest, Key const& src );
                };
                \endcode
            */
            typedef opt::none                           copy_policy;
        };


        /// Metafunction converting option list to \p EllenBinTreeSet traits
        /**
            \p Options are:
            - \p ellen_bintree::key_extractor - key extracting functor, mandatory option. The functor has the following prototype:
                \code
                    struct key_extractor {
                        void operator ()( Key& dest, T const& src );
                    };
                \endcode
                It should initialize \p dest key from \p src data. The functor is used to initialize internal nodes.
            - \p opt::compare - key compare functor. No default functor is provided.
                If the option is not specified, \p %opt::less is used.
            - \p opt::less - specifies binary predicate used for key compare. At least \p %opt::compare or \p %opt::less should be defined.
            - \p opt::item_counter - the type of item counter, default is disabled (\p atomicity::empty_item_counter).
                To enable it use \p atomicity::item_counter or \p atomicity::cache_friendly_item_counter
            - \p opt::memory_model - C++ memory ordering model. Can be \p opt::v::relaxed_ordering (relaxed memory model, the default)
                or \p opt::v::sequential_consistent (sequentially consisnent memory model).
            - \p opt::allocator - the allocator for \ref ellen_bintree::node "leaf nodes" which contains data.
                Default is \ref CDS_DEFAULT_ALLOCATOR.
            - \p opt::node_allocator - the allocator for internal nodes. Default is \ref CDS_DEFAULT_ALLOCATOR.
            - \p ellen_bintree::update_desc_allocator - an allocator of \ref ellen_bintree::update_desc "update descriptors",
                default is \ref CDS_DEFAULT_ALLOCATOR.
                Note that update descriptor is helping data structure with short lifetime and it is good candidate for pooling.
                The number of simultaneously existing descriptors is a relatively small number limited the number of threads
                working with the tree and RCU buffer size.
                Therefore, a bounded lock-free container like \p cds::container::VyukovMPMCCycleQueue is good choice for the free-list
                of update descriptors, see \p cds::memory::vyukov_queue_pool free-list implementation.
                Also notice that size of update descriptor is not dependent on the type of data
                stored in the tree so single free-list object can be used for several EllenBinTree-based object.
            - \p opt::stat - internal statistics, by default disabled (\p ellen_bintree::empty_stat). To enable
                it use \p ellen_bintree::stat.
            - \p opt::backoff - back-off strategy, by default no strategy is used (\p cds::backoff::empty)
            - \p opt::rcu_check_deadlock - a deadlock checking policy, only for RCU-based tree.
                Default is \p opt::v::rcu_throw_deadlock.
        */
        template <typename... Options>
        struct make_set_traits {
#   ifdef CDS_DOXYGEN_INVOKED
            typedef implementation_defined type ;   ///< Metafunction result
#   else
            typedef typename cds::opt::make_options<
                typename cds::opt::find_type_traits< traits, Options... >::type
                ,Options...
            >::type   type;
#   endif
        };

        /// Metafunction converting option list to \p EllenBinTreeMap traits
        /**
            \p Options are:
            - \p opt::compare - key compare functor. No default functor is provided.
                If the option is not specified, \p %opt::less is used.
            - \p opt::less - specifies binary predicate used for key compare. At least \p %opt::compare or \p %opt::less should be defined.
            - \p opt::item_counter - the type of item counter, default is disabled (\p atomicity::empty_item_counter).
                To enable it use \p atomicity::item_counter or \p atomicity::cache_friendly_item_counter
            - opt::memory_model - C++ memory ordering model. Can be \p opt::v::relaxed_ordering (relaxed memory model, the default)
                or \p opt::v::sequential_consistent (sequentially consisnent memory model).
            - \p opt::allocator - the allocator used for \ref ellen_bintree::map_node "leaf nodes" which contains data.
                Default is \ref CDS_DEFAULT_ALLOCATOR.
            - \p opt::node_allocator - the allocator used for \ref ellen_bintree::internal_node "internal nodes".
                Default is \ref CDS_DEFAULT_ALLOCATOR.
            - \p ellen_bintree::update_desc_allocator - an allocator of \ref ellen_bintree::update_desc "update descriptors",
                default is \ref CDS_DEFAULT_ALLOCATOR.
                Note that update descriptor is helping data structure with short lifetime and it is good candidate for pooling.
                The number of simultaneously existing descriptors is a relatively small number limited the number of threads
                working with the tree and RCU buffer size.
                Therefore, a bounded lock-free container like \p cds::container::VyukovMPMCCycleQueue is good choice for the free-list
                of update descriptors, see \p cds::memory::vyukov_queue_pool free-list implementation.
                Also notice that size of update descriptor is not dependent on the type of data
                stored in the tree so single free-list object can be used for several EllenBinTree-based object.
            - \p opt::stat - internal statistics, by default disabled (\p ellen_bintree::empty_stat). To enable
                it use \p ellen_bintree::stat.
            - \p opt::backoff - back-off strategy, by default no strategy is used (\p cds::backoff::empty)
            - \p opt::rcu_check_deadlock - a deadlock checking policy, only for RCU-based tree. Default is \p opt::v::rcu_throw_deadlock
            - opt::copy_policy - key copying policy defines a functor to copy leaf node's key to internal node.
                By default, assignment operator is used.
                The copy functor interface is:
                \code
                struct copy_functor {
                    void operator()( Key& dest, Key const& src );
                };
                \endcode
        */
        template <typename... Options>
        struct make_map_traits {
#   ifdef CDS_DOXYGEN_INVOKED
            typedef implementation_defined type ;   ///< Metafunction result
#   else
            typedef typename cds::opt::make_options<
                typename cds::opt::find_type_traits< traits, Options... >::type
                ,Options...
            >::type   type;
#   endif
        };

        //@cond
        namespace details {

            template < class GC, typename Key, typename T, class Traits>
            struct make_ellen_bintree_set
            {
                typedef GC      gc;
                typedef Key     key_type;
                typedef T       value_type;
                typedef Traits  original_traits;

                typedef node< gc, value_type >  leaf_node;

                struct intrusive_key_extractor
                {
                    void operator()( key_type& dest, leaf_node const& src ) const
                    {
                        typename original_traits::key_extractor()( dest, src.m_Value );
                    }
                };

                struct value_accessor
                {
                    value_type const& operator()( leaf_node const& node ) const
                    {
                        return node.m_Value;
                    }
                };

                typedef typename cds::opt::details::make_comparator< value_type, original_traits, false >::type key_comparator;

                typedef cds::details::Allocator< leaf_node, typename original_traits::allocator> cxx_leaf_node_allocator;
                struct leaf_deallocator
                {
                    void operator()( leaf_node * p ) const
                    {
                        cxx_leaf_node_allocator().Delete( p );
                    }
                };

                struct intrusive_traits: public original_traits
                {
                    typedef cds::intrusive::ellen_bintree::base_hook< cds::opt::gc< gc >> hook;
                    typedef intrusive_key_extractor key_extractor;
                    typedef leaf_deallocator        disposer;
                    typedef cds::details::compare_wrapper< leaf_node, key_comparator, value_accessor > compare;
                };

                // Metafunction result
                typedef cds::intrusive::EllenBinTree< gc, key_type, leaf_node, intrusive_traits > type;
            };

            template < class GC, typename Key, typename T, class Traits>
            struct make_ellen_bintree_map
            {
                typedef GC      gc;
                typedef Key     key_type;
                typedef T       mapped_type;
                typedef map_node< gc, key_type, mapped_type >   leaf_node;
                typedef typename leaf_node::value_type          value_type;

                typedef Traits  original_traits;

                struct assignment_copy_policy {
                    void operator()( key_type& dest, key_type const& src )
                    {
                        dest = src;
                    }
                };
                typedef typename std::conditional<
                    std::is_same< typename original_traits::copy_policy, opt::none >::value,
                    assignment_copy_policy,
                    typename original_traits::copy_policy
                >::type copy_policy;

                struct intrusive_key_extractor
                {
                    void operator()( key_type& dest, leaf_node const& src ) const
                    {
                        copy_policy()( dest, src.m_Value.first );
                    }
                };

                struct key_accessor
                {
                    key_type const& operator()( leaf_node const& node ) const
                    {
                        return node.m_Value.first;
                    }
                };

                typedef typename cds::opt::details::make_comparator< key_type, original_traits, false >::type key_comparator;

                typedef cds::details::Allocator< leaf_node, typename original_traits::allocator>    cxx_leaf_node_allocator;
                struct leaf_deallocator
                {
                    void operator()( leaf_node * p ) const
                    {
                        cxx_leaf_node_allocator().Delete( p );
                    }
                };

                struct intrusive_traits: public original_traits
                {
                    typedef cds::intrusive::ellen_bintree::base_hook< cds::opt::gc< gc > >  hook;
                    typedef intrusive_key_extractor key_extractor;
                    typedef leaf_deallocator        disposer;
                    typedef cds::details::compare_wrapper< leaf_node, key_comparator, key_accessor >    compare;
                };

                // Metafunction result
                typedef cds::intrusive::EllenBinTree< gc, key_type, leaf_node, intrusive_traits >    type;
            };

        } // namespace details
        //@endcond
    } // namespace ellen_bintree

    // Forward declarations
    //@cond
    template < class GC, typename Key, typename T, class Traits = ellen_bintree::traits >
    class EllenBinTreeSet;

    template < class GC, typename Key, typename T, class Traits = ellen_bintree::traits >
    class EllenBinTreeMap;
    //@endcond

}} // namespace cds::container

#endif // #ifndef CDSLIB_CONTAINER_DETAILS_ELLEN_BINTREE_BASE_H