Clean up memory by adding unregister method to CDev

src/lib/cdev/CDev.cpp

@@ -395,4 +395,27 @@ CDev::remove_poll_waiter(px4_pollfd_struct_t *fds)
 	return -EINVAL;
 }
 
+int CDev::unregister_driver_and_memory()
+{
+	int retval = PX4_OK;
+
+	if (_registered) {
+		unregister_driver(_devname);
+		_registered = false;
+
+	} else {
+		retval = -ENODEV;
+	}
+
+	if (_devname != nullptr) {
+		free((void *)_devname);
+		_devname = nullptr;
+
+	} else {
+		retval = -ENODEV;
+	}
+
+	return retval;
+}
+
 } // namespace cdev

src/lib/cdev/CDev.hpp

@@ -264,6 +264,17 @@ class __EXPORT CDev
 
 	px4_sem_t	_lock; /**< lock to protect access to all class members (also for derived classes) */
 
+
+	/**
+	* First, unregisters the driver. Next, free the memory for the devname,
+	* in case it was expected to have ownership. Sets devname to nullptr.
+	*
+	* This is only needed if the ownership of the devname was passed to the CDev, otherwise ~CDev handles it.
+	*
+	* @return  PX4_OK on success, -ENODEV if the devname is already nullptr
+	*/
+	int unregister_driver_and_memory();
+
 private:
 	const char	*_devname{nullptr};		/**< device node name */
 

src/modules/uORB/uORBDeviceNode.cpp

@@ -33,7 +33,6 @@
 
 #include "uORBDeviceNode.hpp"
 
-#include "uORBDeviceNode.hpp"
 #include "uORBUtils.hpp"
 #include "uORBManager.hpp"
 
@@ -61,8 +60,7 @@ uORB::DeviceNode::DeviceNode(const struct orb_metadata *meta, const uint8_t inst
 	_meta(meta),
 	_instance(instance),
 	_priority(priority),
-	_queue_size(queue_size),
-	_devname(path)
+	_queue_size(queue_size)
 {
 }
 
@@ -72,10 +70,7 @@ uORB::DeviceNode::~DeviceNode()
 		delete[] _data;
 	}
 
-	if (_devname != nullptr) {
-		free((void *)_devname);
-		_devname = nullptr;
-	}
+	CDev::unregister_driver_and_memory();
 }
 
 int

src/modules/uORB/uORBDeviceNode.hpp

@@ -273,7 +273,6 @@ class uORB::DeviceNode : public cdev::CDev, public ListNode<uORB::DeviceNode *>
 	bool _published{false};  /**< has ever data been published */
 	uint8_t _queue_size; /**< maximum number of elements in the queue */
 	int8_t _subscriber_count{0};
-	const char *_devname; /**< keep this to delete at teardown, since CDev doesn't */
 
 	px4_task_t _publisher{0}; /**< if nonzero, current publisher. Only used inside the advertise call.
 						We allow one publisher to have an open file descriptor at the same time. */