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#include "LandDetector.h"
#include <unistd.h> //usleep
#include <drivers/drv_hrt.h>
LandDetector::LandDetector() :
_landDetectedPub(-1),
_landDetected({0, false}),
_taskShouldExit(false),
_taskIsRunning(false)
{
//Advertise the first land detected uORB
_landDetected.timestamp = hrt_absolute_time();
_landDetected.landed = false;
_landDetectedPub = orb_advertise(ORB_ID(vehicle_land_detected), &_landDetected);
}
LandDetector::~LandDetector()
{
_taskShouldExit = true;
close(_landDetectedPub);
}
void LandDetector::shutdown()
{
_taskShouldExit = true;
}
void LandDetector::start()
{
//Make sure this method has not already been called by another thread
if(isRunning()) {
return;
}
//Task is now running, keep doing so until shutdown() has been called
_taskIsRunning = true;
_taskShouldExit = false;
while(isRunning()) {
bool landDetected = update();
//Publish if land detection state has changed
if (_landDetected.landed != landDetected) {
_landDetected.timestamp = hrt_absolute_time();
_landDetected.landed = landDetected;
/* publish the land detected broadcast */
orb_publish(ORB_ID(vehicle_land_detected), _landDetectedPub, &_landDetected);
}
//Limit loop rate
usleep(1000000 / LAND_DETECTOR_UPDATE_RATE);
}
_taskIsRunning = false;
_exit(0);
}
bool LandDetector::orb_update(const struct orb_metadata *meta, int handle, void *buffer)
{
bool newData = false;
//Check if there is new data to grab
if (orb_check(handle, &newData) != OK) {
return false;
}
if (!newData) {
return false;
}
if (orb_copy(meta, handle, buffer) != OK) {
return false;
}
return true;
}
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