LandDetector: Merged fixedwing and multicopter into one module handling both algorithms

src/modules/land_detector/LandDetector.cpp

@@ -0,0 +1,77 @@
+#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;
+}