PacketRegistry.ih

Go to the documentation of this file.

//
// Copyright (c) 2020 Fraunhofer Institute for Applied Information Technology (FIT)
//                    Network Research Group (NET)
//                    Schloss Birlinghoven, 53754 Sankt Augustin, GERMANY
//                    Contact: support@wiback.org
//
// This file is part of the SENF code tree.
// It is licensed under the 3-clause BSD License (aka New BSD License).
// See LICENSE.txt in the top level directory for details or visit
// https://opensource.org/licenses/BSD-3-Clause
//


/** \file
    \brief PacketRegistry internal header */

#ifndef IH_SENF_Packets_PacketRegistry_
#define IH_SENF_Packets_PacketRegistry_ 1

// Custom includes
#include <limits>
#include <boost/multi_index_container.hpp>
#include <boost/multi_index/ordered_index.hpp>
#include <boost/multi_index/composite_key.hpp>
#include <boost/multi_index/member.hpp>
#include <boost/multi_index/mem_fun.hpp>
#include <boost/intrusive_ptr.hpp>
#include <boost/noncopyable.hpp>
#include <senf/Utils/TypeIdValue.hh>

//-/////////////////////////////////////////////////////////////////////////////////////////////////

namespace senf {
namespace detail {

    struct TypeInfoCompare
    {
        bool operator()(std::type_info const & a, std::type_info const & b) const
            { return a.before(b); }
    };

    /** \brief Internal: Registry implementation base-class and registry of registries

        \internal
     */
    class PacketRegistryImplBase
        : private boost::noncopyable
    {
    public:
        virtual ~PacketRegistryImplBase();

        static void dump(std::ostream & os);
        static void clear();

    protected:
        typedef std::map<std::string, PacketRegistryImplBase*>  RegistryMap;
        static RegistryMap & registries();

    private:
        virtual bool v_empty() const = 0;
        virtual void v_dump(std::ostream & os) const = 0;
        virtual void v_clear() = 0;
    };

    /** \brief Internal: Singleton class implementing the packet registry.

        \internal
     */
    template <class KeyType>
    class PacketRegistryImpl
        : public PacketRegistryImplBase
    {
    public:
        typedef KeyType key_t;

        struct Entry : public intrusive_refcount
        {
            typedef boost::intrusive_ptr<Entry> ptr;

            Entry(KeyType const & key_, int priority_);
            virtual ~Entry();

            virtual Packet::factory_t factory() const = 0;

            virtual std::string name() const = 0;
            virtual std::type_info const & type() const = 0;

            KeyType key;
            int priority;
        };

    private:
        struct ByKey {};
        struct ByType {};

        struct RegistryIndices
            : public boost::multi_index::indexed_by<
                boost::multi_index::ordered_unique<
                    boost::multi_index::tag<ByKey>,
                    boost::multi_index::composite_key<
                        Entry,
                        boost::multi_index::member<Entry,KeyType,&Entry::key>,
                        boost::multi_index::member<Entry,int,&Entry::priority> >,
                    boost::multi_index::composite_key_compare<
                        std::less<KeyType>,
                        std::greater<int> > >,
                boost::multi_index::ordered_unique<
                    boost::multi_index::tag<ByType>,
                    boost::multi_index::const_mem_fun<Entry,std::type_info const &,&Entry::type>,
                    TypeInfoCompare> >
        {};

        typedef boost::multi_index_container<typename Entry::ptr, RegistryIndices> Registry;
        typedef typename Registry::template index<ByKey>::type RegistryByKey;
        typedef typename Registry::template index<ByType>::type RegistryByType;

        template <class PacketType>
        struct EntryImpl : public Entry
        {
            EntryImpl(KeyType const & key, int priority);

            virtual Packet::factory_t factory() const;
            virtual std::string name() const;
            virtual std::type_info const & type() const;
        };

    public:
        //-/////////////////////////////////////////////////////////////////////////////////////////
        // Types

        typedef typename Registry::template index<ByKey>::type::const_iterator iterator;

        //-/////////////////////////////////////////////////////////////////////////////////////////
        ///\name Structors and default members
        //\{

        PacketRegistryImpl(std::string const & name);

        //\}
        //-/////////////////////////////////////////////////////////////////////////////////////////

        template <class PacketType>
        void registerPacket(key_t key, int priority=0);

        template <class PacketType>
        void unregisterPacket();
        void unregisterPacket(key_t key, int priority=0);

        key_t key(senf::TypeIdValue const & type);
        boost::optional<key_t> key(senf::TypeIdValue const & type, bool);

        Entry const & lookup(key_t key) const;
        Entry const * lookup(key_t key, bool) const;

        iterator begin() const;
        iterator end() const;

    protected:

    private:
        virtual bool v_empty() const;
        virtual void v_dump(std::ostream & os) const;
        virtual void v_clear();

        Registry registry_;
        RegistryByKey & registryByKey_;
        RegistryByType & registryByType_;
    };

    template <class KeyType, bool is_integral=std::numeric_limits<KeyType>::is_integer>
    struct DumpKey
    {
        static void dump(KeyType const & v, std::ostream & os);
    };

    template <class KeyType>
    struct DumpKey<KeyType, true>
    {
        static void dump(KeyType const & v, std::ostream & os);
    };

}}

//-/////////////////////////////////////////////////////////////////////////////////////////////////
#endif


// Local Variables:
// mode: c++
// fill-column: 100
// c-file-style: "senf"
// indent-tabs-mode: nil
// ispell-local-dictionary: "american"
// compile-command: "scons -u test"
// comment-column: 40
// End: