uORBDeviceMaster.hpp

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#pragma once

#include <stdint.h>

#include "uORBCommon.hpp"
#include <px4_platform_common/posix.h>

namespace uORB
{
class DeviceNode;
class DeviceMaster;
class Manager;
}

#include <string.h>
#include <stdlib.h>

#include <containers/List.hpp>

/**
 * Master control device for ObjDev.
 *
 * Used primarily to create new objects via the ORBIOCCREATE
 * ioctl.
 */
class uORB::DeviceMaster
{
public:

    int advertise(const struct orb_metadata *meta, bool is_advertiser, int *instance, int priority);

    /**
     * Public interface for getDeviceNodeLocked(). Takes care of synchronization.
     * @return node if exists, nullptr otherwise
     */
    uORB::DeviceNode *getDeviceNode(const char *node_name);
    uORB::DeviceNode *getDeviceNode(const struct orb_metadata *meta, const uint8_t instance);

    /**
     * Print statistics for each existing topic.
     * @param reset if true, reset statistics afterwards
     */
    void printStatistics(bool reset);

    /**
     * Continuously print statistics, like the unix top command for processes.
     * Exited when the user presses the enter key.
     * @param topic_filter list of topic filters: if set, each string can be a substring for topics to match.
     *        Or it can be '-a', which means to print all topics instead of only currently publishing ones.
     * @param num_filters
     */
    void showTop(char **topic_filter, int num_filters);

private:
    // Private constructor, uORB::Manager takes care of its creation
    DeviceMaster();
    ~DeviceMaster();

    struct DeviceNodeStatisticsData {
        DeviceNode *node;
        uint32_t last_lost_msg_count;
        unsigned int last_pub_msg_count;
        uint32_t lost_msg_delta;
        unsigned int pub_msg_delta;
        DeviceNodeStatisticsData *next = nullptr;
    };

    int addNewDeviceNodes(DeviceNodeStatisticsData **first_node, int &num_topics, size_t &max_topic_name_length,
                  char **topic_filter, int num_filters);

    friend class uORB::Manager;

    /**
     * Find a node give its name.
     * _lock must already be held when calling this.
     * @return node if exists, nullptr otherwise
     */
    uORB::DeviceNode *getDeviceNodeLocked(const struct orb_metadata *meta, const uint8_t instance);

    List<uORB::DeviceNode *> _node_list;

    hrt_abstime       _last_statistics_output;

    px4_sem_t   _lock; /**< lock to protect access to all class members (also for derived classes) */

    void        lock() { do {} while (px4_sem_wait(&_lock) != 0); }
    void        unlock() { px4_sem_post(&_lock); }
};