add subscriber handler and status displays

src/modules/events/status_display.h

@@ -0,0 +1,101 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2017 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file status_display.h
+ * Status Display decouple the LED and tune form the original commander
+ *
+ * @author Simone Guscetti <simone@px4.io>
+ */
+
+#pragma once
+
+#include "subscriber_handler.h"
+
+#include <drivers/drv_hrt.h>
+
+#include <uORB/uORB.h>
+#include <uORB/topics/battery_status.h>
+#include <uORB/topics/cpuload.h>
+#include <uORB/topics/led_control.h>
+#include <uORB/topics/vehicle_status.h>
+#include <uORB/topics/vehicle_status_flags.h>
+
+namespace status
+{
+
+class StatusDisplay
+{
+public:
+
+	StatusDisplay(const events::SubscriberHandler &subscriber_handler);
+
+	/** regularily called to handle state updates */
+	void process();
+
+protected:
+	/**
+	 * check for topic updates
+	 * @return true if one or more topic got updated
+	 */
+	bool check_for_updates();
+
+	/**
+	 * handle LED logic changes & call publish()
+	 */
+	void set_leds();
+
+	/** publish LED control */
+	void publish();
+
+	// TODO: review if there is a better variant that allocate this in the memory
+	struct battery_status_s _battery_status = {};
+	struct cpuload_s _cpu_load = {};
+	struct vehicle_status_s _vehicle_status = {};
+	struct vehicle_status_flags_s _vehicle_status_flags = {};
+	struct vehicle_attitude_s _vehicle_attitude = {};
+
+	struct led_control_s _led_control = {};
+
+private:
+	bool _old_gps_lock_valid = false;
+	bool _old_home_position_valid = false;
+	bool _low_battery = false;
+	bool _critical_battery = false;
+	int _old_nav_state = -1;
+	int _old_battery_status_warning = -1;
+	orb_advert_t _led_control_pub = nullptr;
+	const events::SubscriberHandler &_subscriber_handler;
+};
+
+} /* status */