PublicationQueued.hpp

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/**
 * @file PublicationQueued.hpp
 *
 */

#pragma once

#include <px4_platform_common/defines.h>
#include <systemlib/err.h>
#include <uORB/uORB.h>

namespace uORB
{

/**
 * Queued publication with queue length set as a message constant (ORB_QUEUE_LENGTH)
 */
template<typename T>
class PublicationQueued
{
public:

    /**
     * Constructor
     *
     * @param meta The uORB metadata (usually from the ORB_ID() macro) for the topic.
     */
    PublicationQueued(const orb_metadata *meta) : _meta(meta) {}
    ~PublicationQueued()
    {
        //orb_unadvertise(_handle);
    }

    /**
     * Publish the struct
     * @param data The uORB message struct we are updating.
     */
    bool publish(const T &data)
    {
        if (_handle != nullptr) {
            return (orb_publish(_meta, _handle, &data) == PX4_OK);

        } else {
            orb_advert_t handle = orb_advertise_queue(_meta, &data, T::ORB_QUEUE_LENGTH);

            if (handle != nullptr) {
                _handle = handle;
                return true;
            }
        }

        return false;
    }

protected:
    const orb_metadata *_meta;

    orb_advert_t _handle{nullptr};
};

} // namespace uORB