Class thread_specific_data

dlib/threads/thread_specific_data_extension.h:19–132

        typename T
        >
    class thread_specific_data
    {
        /*!
            CONVENTION
                - for all valid ID:
                  (*items[ID]) == pointer to the data for thread with id ID
        !*/
    public:

        thread_specific_data (
        )
        {
            thread_end_handler_calls_left = 0;
        }

        ~thread_specific_data (
        )
        {
            // We should only call the unregister_thread_end_handler function if there are
            // some outstanding callbacks we expect to get.  Otherwise lets avoid calling it
            // since the dlib state that maintains the registered thread end handlers may have
            // been destructed already (since the program might be in the process of terminating).
            bool call_unregister = false;
            m.lock();
            if (thread_end_handler_calls_left > 0)
                call_unregister = true;
            m.unlock();

            if (call_unregister)
                unregister_thread_end_handler(const_cast<thread_specific_data&>(*this),&thread_specific_data::thread_end_handler);

            auto_mutex M(m);
            items.reset();
            while (items.move_next())
            {
                delete items.element().value();
            }
        }

        inline T& data (
        ) { return get_data(); }

        inline const T& data (
        ) const { return get_data(); }

    private:

        T& get_data (
        ) const
        {
            thread_id_type id = get_thread_id();
            auto_mutex M(m);

            T** item = items[id];
            if (item)
            {
                return **item;
            }