[FlightTasks] Added class enum for FlightTasks errors (#12822)

src/lib/FlightTasks/FlightTasks.cpp

@@ -57,11 +57,11 @@ const landing_gear_s FlightTasks::getGear()
 	}
 }
 
-int FlightTasks::switchTask(FlightTaskIndex new_task_index)
+FlightTaskError FlightTasks::switchTask(FlightTaskIndex new_task_index)
 {
 	// switch to the running task, nothing to do
 	if (new_task_index == _current_task.index) {
-		return 0;
+		return FlightTaskError::NoError;
 	}
 
 	// Save current setpoints for the nex FlightTask
@@ -69,12 +69,12 @@ int FlightTasks::switchTask(FlightTaskIndex new_task_index)
 
 	if (_initTask(new_task_index)) {
 		// invalid task
-		return -1;
+		return FlightTaskError::InvalidTask;
 	}
 
 	if (!_current_task.task) {
 		// no task running
-		return 0;
+		return FlightTaskError::NoError;
 	}
 
 	// subscription failed
@@ -82,7 +82,7 @@ int FlightTasks::switchTask(FlightTaskIndex new_task_index)
 		_current_task.task->~FlightTask();
 		_current_task.task = nullptr;
 		_current_task.index = FlightTaskIndex::None;
-		return -2;
+		return FlightTaskError::SubscriptionFailed;
 	}
 
 	_subscription_array.forcedUpdate(); // make sure data is available for all new subscriptions
@@ -92,13 +92,13 @@ int FlightTasks::switchTask(FlightTaskIndex new_task_index)
 		_current_task.task->~FlightTask();
 		_current_task.task = nullptr;
 		_current_task.index = FlightTaskIndex::None;
-		return -3;
+		return FlightTaskError::ActivationFailed;
 	}
 
-	return 0;
+	return FlightTaskError::NoError;
 }
 
-int FlightTasks::switchTask(int new_task_index)
+FlightTaskError FlightTasks::switchTask(int new_task_index)
 {
 	// make sure we are in range of the enumeration before casting
 	if (static_cast<int>(FlightTaskIndex::None) <= new_task_index &&
@@ -107,7 +107,7 @@ int FlightTasks::switchTask(int new_task_index)
 	}
 
 	switchTask(FlightTaskIndex::None);
-	return -1;
+	return FlightTaskError::InvalidTask;
 }
 
 void FlightTasks::handleParameterUpdate()
@@ -117,10 +117,10 @@ void FlightTasks::handleParameterUpdate()
 	}
 }
 
-const char *FlightTasks::errorToString(const int error)
+const char *FlightTasks::errorToString(const FlightTaskError error)
 {
 	for (auto e : _taskError) {
-		if (e.error == error) {
+		if (static_cast<FlightTaskError>(e.error) == error) {
 			return e.msg;
 		}
 	}
@@ -157,11 +157,11 @@ void FlightTasks::_updateCommand()
 	}
 
 	// switch to the commanded task
-	int switch_result = switchTask(desired_task);
+	FlightTaskError switch_result = switchTask(desired_task);
 	uint8_t cmd_result = vehicle_command_ack_s::VEHICLE_RESULT_FAILED;
 
 	// if we are in/switched to the desired task
-	if (switch_result >= 0) {
+	if (switch_result >= FlightTaskError::NoError) {
 		cmd_result = vehicle_command_ack_s::VEHICLE_RESULT_ACCEPTED;
 
 		// if the task is running apply parameters to it and see if it rejects
@@ -169,7 +169,7 @@ void FlightTasks::_updateCommand()
 			cmd_result = vehicle_command_ack_s::VEHICLE_RESULT_DENIED;
 
 			// if we just switched and parameters are not accepted, go to failsafe
-			if (switch_result == 1) {
+			if (switch_result >= FlightTaskError::NoError) {
 				switchTask(FlightTaskIndex::ManualPosition);
 				cmd_result = vehicle_command_ack_s::VEHICLE_RESULT_FAILED;
 			}
@@ -181,7 +181,7 @@ void FlightTasks::_updateCommand()
 	command_ack.timestamp = hrt_absolute_time();
 	command_ack.command = command.command;
 	command_ack.result = cmd_result;
-	command_ack.result_param1 = switch_result;
+	command_ack.result_param1 = static_cast<int>(switch_result);
 	command_ack.target_system = command.source_system;
 	command_ack.target_component = command.source_component;
 

src/lib/FlightTasks/FlightTasks.hpp

@@ -52,6 +52,13 @@
 
 #include <new>
 
+enum class FlightTaskError : int {
+	NoError = 0,
+	InvalidTask = -1,
+	SubscriptionFailed = -2,
+	ActivationFailed = -3
+};
+
 class FlightTasks
 {
 public:
@@ -102,17 +109,17 @@ public:
 
 	/**
 	 * Switch to the next task in the available list (for testing)
-	 * @return 1 on success, <0 on error
+	 * @return 0 on success, <0 on error
 	 */
-	int switchTask() { return switchTask(static_cast<int>(_current_task.index) + 1); }
+	FlightTaskError switchTask() { return switchTask(static_cast<int>(_current_task.index) + 1); }
 
 	/**
 	 * Switch to a specific task (for normal usage)
 	 * @param task index to switch to
-	 * @return 1 on success, 0 on no change, <0 on error
+	 * @return 0 on success, <0 on error
 	 */
-	int switchTask(FlightTaskIndex new_task_index);
-	int switchTask(int new_task_index);
+	FlightTaskError switchTask(FlightTaskIndex new_task_index);
+	FlightTaskError switchTask(int new_task_index);
 
 	/**
 	 * Get the number of the active task
@@ -134,7 +141,7 @@ public:
 	/**
 	 * Call this method to get the description of a task error.
 	 */
-	const char *errorToString(const int error);
+	const char *errorToString(const FlightTaskError error);
 
 	/**
 	 * Sets an external yaw handler. The active flight task can use the yaw handler to implement a different yaw control strategy.
@@ -174,10 +181,10 @@ private:
 	 * Map from Error int to user friendly string.
 	 */
 	task_error_t _taskError[_numError] = {
-		{0, "No Error"},
-		{-1, "Invalid Task "},
-		{-2, "Subscription Failed"},
-		{-3, "Activation Failed"}
+		{static_cast<int>(FlightTaskError::NoError), "No Error"},
+		{static_cast<int>(FlightTaskError::InvalidTask), "Invalid Task "},
+		{static_cast<int>(FlightTaskError::SubscriptionFailed), "Subscription Failed"},
+		{static_cast<int>(FlightTaskError::ActivationFailed), "Activation Failed"}
 	};
 	/**
 	 * Check for vehicle commands (received via MAVLink), evaluate and acknowledge them

src/modules/mc_pos_control/mc_pos_control_main.cpp

@@ -739,9 +739,9 @@ MulticopterPositionControl::start_flight_task()
 
 	if (_vehicle_status.in_transition_mode) {
 		should_disable_task = false;
-		int error = _flight_tasks.switchTask(FlightTaskIndex::Transition);
+		FlightTaskError error = _flight_tasks.switchTask(FlightTaskIndex::Transition);
 
-		if (error != 0) {
+		if (error != FlightTaskError::NoError) {
 			if (prev_failure_count == 0) {
 				PX4_WARN("Transition activation failed with error: %s", _flight_tasks.errorToString(error));
 			}
@@ -766,9 +766,9 @@ MulticopterPositionControl::start_flight_task()
 		_control_mode.flag_control_acceleration_enabled)) {
 
 		should_disable_task = false;
-		int error = _flight_tasks.switchTask(FlightTaskIndex::Offboard);
+		FlightTaskError error = _flight_tasks.switchTask(FlightTaskIndex::Offboard);
 
-		if (error != 0) {
+		if (error != FlightTaskError::NoError) {
 			if (prev_failure_count == 0) {
 				PX4_WARN("Offboard activation failed with error: %s", _flight_tasks.errorToString(error));
 			}
@@ -785,9 +785,9 @@ MulticopterPositionControl::start_flight_task()
 	// Auto-follow me
 	if (_vehicle_status.nav_state == vehicle_status_s::NAVIGATION_STATE_AUTO_FOLLOW_TARGET) {
 		should_disable_task = false;
-		int error = _flight_tasks.switchTask(FlightTaskIndex::AutoFollowMe);
+		FlightTaskError error = _flight_tasks.switchTask(FlightTaskIndex::AutoFollowMe);
 
-		if (error != 0) {
+		if (error != FlightTaskError::NoError) {
 			if (prev_failure_count == 0) {
 				PX4_WARN("Follow-Me activation failed with error: %s", _flight_tasks.errorToString(error));
 			}
@@ -803,7 +803,7 @@ MulticopterPositionControl::start_flight_task()
 	} else if (_control_mode.flag_control_auto_enabled) {
 		// Auto related maneuvers
 		should_disable_task = false;
-		int error = 0;
+		FlightTaskError error = FlightTaskError::NoError;
 
 		switch (_param_mpc_auto_mode.get()) {
 		case 1:
@@ -815,7 +815,7 @@ MulticopterPositionControl::start_flight_task()
 			break;
 		}
 
-		if (error != 0) {
+		if (error != FlightTaskError::NoError) {
 			if (prev_failure_count == 0) {
 				PX4_WARN("Auto activation failed with error: %s", _flight_tasks.errorToString(error));
 			}
@@ -832,7 +832,7 @@ MulticopterPositionControl::start_flight_task()
 	// manual position control
 	if (_vehicle_status.nav_state == vehicle_status_s::NAVIGATION_STATE_POSCTL || task_failure) {
 		should_disable_task = false;
-		int error = 0;
+		FlightTaskError error = FlightTaskError::NoError;
 
 		switch (_param_mpc_pos_mode.get()) {
 		case 1:
@@ -852,7 +852,7 @@ MulticopterPositionControl::start_flight_task()
 			break;
 		}
 
-		if (error != 0) {
+		if (error != FlightTaskError::NoError) {
 			if (prev_failure_count == 0) {
 				PX4_WARN("Position-Ctrl activation failed with error: %s", _flight_tasks.errorToString(error));
 			}
@@ -869,7 +869,7 @@ MulticopterPositionControl::start_flight_task()
 	// manual altitude control
 	if (_vehicle_status.nav_state == vehicle_status_s::NAVIGATION_STATE_ALTCTL || task_failure) {
 		should_disable_task = false;
-		int error = 0;
+		FlightTaskError error = FlightTaskError::NoError;
 
 		switch (_param_mpc_pos_mode.get()) {
 		case 1:
@@ -885,7 +885,7 @@ MulticopterPositionControl::start_flight_task()
 			break;
 		}
 
-		if (error != 0) {
+		if (error != FlightTaskError::NoError) {
 			if (prev_failure_count == 0) {
 				PX4_WARN("Altitude-Ctrl activation failed with error: %s", _flight_tasks.errorToString(error));
 			}
@@ -908,9 +908,9 @@ MulticopterPositionControl::start_flight_task()
 
 		// for some reason no flighttask was able to start.
 		// go into failsafe flighttask
-		int error = _flight_tasks.switchTask(FlightTaskIndex::Failsafe);
+		FlightTaskError error = _flight_tasks.switchTask(FlightTaskIndex::Failsafe);
 
-		if (error != 0) {
+		if (error != FlightTaskError::NoError) {
 			// No task was activated.
 			_flight_tasks.switchTask(FlightTaskIndex::None);
 		}