mavlink_get_info.h

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#pragma once

#ifdef MAVLINK_USE_MESSAGE_INFO
#define MAVLINK_HAVE_GET_MESSAGE_INFO

/*
  return the message_info struct for a message
*/
MAVLINK_HELPER const mavlink_message_info_t *mavlink_get_message_info_by_id(uint32_t msgid)
{
        static const mavlink_message_info_t mavlink_message_info[] = MAVLINK_MESSAGE_INFO;
        /*
          use a bisection search to find the right entry. A perfect hash may be better
          Note that this assumes the table is sorted with primary key msgid
        */
        uint32_t low=0, high=sizeof(mavlink_message_info)/sizeof(mavlink_message_info[0]);
        while (low < high) {
            uint32_t mid = (low+1+high)/2;
            if (msgid < mavlink_message_info[mid].msgid) {
                high = mid-1;
                continue;
            }
            if (msgid > mavlink_message_info[mid].msgid) {
                low = mid;
                continue;
            }
            low = mid;
            break;
        }
        if (mavlink_message_info[low].msgid == msgid) {
            return &mavlink_message_info[low];
        }
        return NULL;
}

/*
  return the message_info struct for a message
*/
MAVLINK_HELPER const mavlink_message_info_t *mavlink_get_message_info(const mavlink_message_t *msg)
{
    return mavlink_get_message_info_by_id(msg->msgid);
}

/*
  return the message_info struct for a message
*/
MAVLINK_HELPER const mavlink_message_info_t *mavlink_get_message_info_by_name(const char *name)
{
        static const struct { const char *name; uint32_t msgid; } mavlink_message_names[] = MAVLINK_MESSAGE_NAMES;
        /*
          use a bisection search to find the right entry. A perfect hash may be better
          Note that this assumes the table is sorted with primary key name
        */
        uint32_t low=0, high=sizeof(mavlink_message_names)/sizeof(mavlink_message_names[0]);
        while (low < high) {
            uint32_t mid = (low+1+high)/2;
            int cmp = strcmp(mavlink_message_names[mid].name, name);
            if (cmp == 0) {
                    return mavlink_get_message_info_by_id(mavlink_message_names[mid].msgid);
            }
            if (cmp > 0) {
                high = mid-1;
            } else {
                low = mid;
            }
        }
        return NULL;
}
#endif // MAVLINK_USE_MESSAGE_INFO