resize_port.hpp

/*
   resize_port.hpp - support file for writing LV2 plugins in C++
   Copyright (C) 2012 Michael Fisher <mfisher31@gmail.com>

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 01222-1307  USA
 */

#ifndef LVTK_RESIZE_PORT_HPP
#define LVTK_RESIZE_PORT_HPP

#include <lv2/lv2plug.in/ns/ext/resize-port/resize-port.h>

#include <lvtk/private/types.hpp>

namespace lvtk
{
    typedef enum
    {
        RESIZE_PORT_SUCCESS = LV2_RESIZE_PORT_SUCCESS, 
        RESIZE_PORT_ERR_UNKNOWN = LV2_RESIZE_PORT_ERR_UNKNOWN, 
        RESIZE_PORT_ERR_NO_SPACE = LV2_RESIZE_PORT_ERR_NO_SPACE 
    } ResizePortStatus;

    template<bool Required = true>
    struct ResizePort
    {
        template<class Derived>
        struct I : Extension<Required>
        {
            I() : p_resize_port_resize(NULL) { }

            static void
            map_feature_handlers(FeatureHandlerMap& hmap)
            {
                hmap[LV2_RESIZE_PORT__resize] =
                        &I<Derived>::handle_feature;
            }

            static void
            handle_feature(LV2_Handle instance, FeatureData data)
            {
                Derived* derived = reinterpret_cast<Derived*>(instance);
                I<Derived>* mixin = static_cast<I<Derived>*>(derived);

                mixin->p_resize_port_resize =
                        reinterpret_cast<LV2_Resize_Port_Resize*>(data);

                mixin->m_ok = true;
            }

            bool
            check_ok()
            {
                if (LVTK_DEBUG)
                {
                    std::clog << "    [LV2::ResizePort] Validation "
                            << (this->m_ok ? "succeeded" : "failed")
                            << "." << std::endl;
                }
                return this->m_ok;
            }

        protected:

            ResizePortStatus
            resize (uint32_t index, size_t size)
            {
                if (0 == p_resize_port_resize)
                    return RESIZE_PORT_ERR_UNKNOWN;

                LV2_Resize_Port_Feature_Data data = p_resize_port_resize->data;
                return (ResizePortStatus) p_resize_port_resize->resize (data, index, size);
            }

        private:
            LV2_Resize_Port_Resize * p_resize_port_resize;
        };
    };

} /* namespace lvtk */

#endif /* LVTK_RESIZE_PORT_HPP */