extensive orb_advert_t fixes

The calls to orb_advertise were being mishandled throughout the code.
There were ::close() calls on memory pointers, there were checks
against < 0 when it is a pointer to a object and values larger than
0x7ffffffff are valid. Some places orb_advert_t variables were
being initialized as 0 other places as -1.

The orb_advert_t type was changed to uintptr_t so the pointer value
would not be wrapped as a negative number. This was causing a failure
on ARM.

Tests for < 0 were changed to == 0 since a null pointer is the valid
representation for error, or uninitialized.

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

src/platforms/posix/drivers/accelsim/accelsim.cpp

@@ -369,7 +369,7 @@ ACCELSIM::ACCELSIM(const char* path, enum Rotation rotation) :
 	_mag_range_ga(0.0f),
 	_mag_range_scale(0.0f),
 	_mag_samplerate(0),
-	_accel_topic(-1),
+	_accel_topic(0),
 	_accel_orb_class_instance(-1),
 	_accel_class_instance(-1),
 	_accel_read(0),
@@ -496,7 +496,7 @@ ACCELSIM::init()
 	_accel_topic = orb_advertise_multi(ORB_ID(sensor_accel), &arp,
 		&_accel_orb_class_instance, ORB_PRIO_DEFAULT);
 
-	if (_accel_topic == (orb_advert_t)(-1)) {
+	if (_accel_topic == 0) {
 		PX4_WARN("ADVERT ERR");
 	}
 
@@ -1077,7 +1077,7 @@ ACCELSIM::measure()
 
 		// The first call to measure() is from init() and _accel_topic is not
 		// yet initialized
-		if (_accel_topic != (orb_advert_t)(-1)) {
+		if (_accel_topic != 0) {
 			orb_publish(ORB_ID(sensor_accel), _accel_topic, &accel_report);
 		}
 	}

src/platforms/posix/drivers/airspeedsim/airspeedsim.cpp

@@ -83,8 +83,8 @@ Airspeed::Airspeed(int bus, int address, unsigned conversion_interval, const cha
 	_measure_ticks(0),
 	_collect_phase(false),
 	_diff_pres_offset(0.0f),
-	_airspeed_pub(-1),
-	_subsys_pub(-1),
+	_airspeed_pub(0),
+	_subsys_pub(0),
 	_class_instance(-1),
 	_conversion_interval(conversion_interval),
 	_sample_perf(perf_alloc(PC_ELAPSED, "airspeed_read")),
@@ -143,7 +143,7 @@ Airspeed::init()
 		/* measurement will have generated a report, publish */
 		_airspeed_pub = orb_advertise(ORB_ID(differential_pressure), &arp);
 
-		if (_airspeed_pub < 0)
+		if (_airspeed_pub == 0)
 			PX4_WARN("uORB started?");
 	}
 

src/platforms/posix/drivers/barosim/baro.cpp

@@ -213,7 +213,7 @@ BAROSIM::BAROSIM(device::Device *interface, barosim::prom_u &prom_buf, const cha
 	_OFF(0),
 	_SENS(0),
 	_msl_pressure(101325),
-	_baro_topic(-1),
+	_baro_topic(0),
 	_orb_class_instance(-1),
 	_class_instance(-1),
 	_sample_perf(perf_alloc(PC_ELAPSED, "barosim_read")),
@@ -315,7 +315,7 @@ BAROSIM::init()
 		_baro_topic = orb_advertise_multi(ORB_ID(sensor_baro), &brp,
 				&_orb_class_instance, (is_external()) ? ORB_PRIO_HIGH : ORB_PRIO_DEFAULT);
 
-		if (_baro_topic == (orb_advert_t)(-1)) {
+		if (_baro_topic == 0) {
 			PX4_ERR("failed to create sensor_baro publication");
 		}
 		//PX4_WARN("sensor_baro publication %ld", _baro_topic);
@@ -722,7 +722,7 @@ BAROSIM::collect()
 
 		/* publish it */
 		if (!(_pub_blocked)) {
-			if (_baro_topic != (orb_advert_t)(-1)) {
+			if (_baro_topic != 0) {
 				/* publish it */
 				orb_publish(ORB_ID(sensor_baro), _baro_topic, &report);
 			}

src/platforms/posix/drivers/gyrosim/gyrosim.cpp

@@ -472,7 +472,7 @@ GYROSIM::GYROSIM(const char *path_accel, const char *path_gyro, enum Rotation ro
 	_accel_scale{},
 	_accel_range_scale(0.0f),
 	_accel_range_m_s2(0.0f),
-	_accel_topic(-1),
+	_accel_topic(0),
 	_accel_orb_class_instance(-1),
 	_accel_class_instance(-1),
 	_gyro_reports(nullptr),
@@ -624,7 +624,7 @@ GYROSIM::init()
 	_accel_topic = orb_advertise_multi(ORB_ID(sensor_accel), &arp,
 		&_accel_orb_class_instance, ORB_PRIO_HIGH);
 
-	if (_accel_topic < 0) {
+	if (_accel_topic == 0) {
 		PX4_WARN("ADVERT FAIL");
 	}
 
@@ -636,7 +636,7 @@ GYROSIM::init()
 	_gyro->_gyro_topic = orb_advertise_multi(ORB_ID(sensor_gyro), &grp,
 		&_gyro->_gyro_orb_class_instance, ORB_PRIO_HIGH);
 
-	if (_gyro->_gyro_topic < 0) {
+	if (_gyro->_gyro_topic == 0) {
 		PX4_WARN("ADVERT FAIL");
 	}
 
@@ -1547,7 +1547,7 @@ GYROSIM::print_registers()
 GYROSIM_gyro::GYROSIM_gyro(GYROSIM *parent, const char *path) :
 	VDev("GYROSIM_gyro", path),
 	_parent(parent),
-	_gyro_topic(-1),
+	_gyro_topic(0),
 	_gyro_orb_class_instance(-1),
 	_gyro_class_instance(-1)
 {