clang-tidy modernize-use-nullptr

.clang-tidy

@@ -1,5 +1,7 @@
-Checks:          '-*,readability-braces-around-statements'
-WarningsAsErrors: readability-braces-around-statements
+Checks:          '-*,readability-braces-around-statements,
+		     modernize-use-nullptr'
+WarningsAsErrors: 'readability-braces-around-statements,
+		   modernize-use-nullptr'
 HeaderFilterRegex: '*.h, *.hpp'
 AnalyzeTemporaryDtors: false
 CheckOptions:

src/drivers/device/ringbuffer.cpp

@@ -86,7 +86,7 @@ void
 RingBuffer::flush()
 {
 	while (!empty()) {
-		get(NULL);
+		get(nullptr);
 	}
 }
 
@@ -179,7 +179,7 @@ RingBuffer::force(const void *val, size_t val_size)
 			break;
 		}
 
-		get(NULL);
+		get(nullptr);
 		overwrote = true;
 	}
 
@@ -281,7 +281,7 @@ RingBuffer::get(void *val, size_t val_size)
 			next = _next(candidate);
 
 			/* go ahead and read from this index */
-			if (val != NULL) {
+			if (val != nullptr) {
 				memcpy(val, &_buf[candidate * _item_size], val_size);
 			}
 

src/drivers/device/vdev.cpp

@@ -139,7 +139,7 @@ VDev::register_driver(const char *name, void *data)
 	PX4_DEBUG("VDev::register_driver %s", name);
 	int ret = -ENOSPC;
 
-	if (name == NULL || data == NULL) {
+	if (name == nullptr || data == nullptr) {
 		return -EINVAL;
 	}
 
@@ -156,7 +156,7 @@ VDev::register_driver(const char *name, void *data)
 	}
 
 	for (int i = 0; i < PX4_MAX_DEV; ++i) {
-		if (devmap[i] == NULL) {
+		if (devmap[i] == nullptr) {
 			devmap[i] = new px4_dev_t(name, (void *)data);
 			PX4_DEBUG("Registered DEV %s", name);
 			ret = PX4_OK;
@@ -179,7 +179,7 @@ VDev::unregister_driver(const char *name)
 	PX4_DEBUG("VDev::unregister_driver %s", name);
 	int ret = -EINVAL;
 
-	if (name == NULL) {
+	if (name == nullptr) {
 		return -EINVAL;
 	}
 
@@ -188,7 +188,7 @@ VDev::unregister_driver(const char *name)
 	for (int i = 0; i < PX4_MAX_DEV; ++i) {
 		if (devmap[i] && (strcmp(name, devmap[i]->name) == 0)) {
 			delete devmap[i];
-			devmap[i] = NULL;
+			devmap[i] = nullptr;
 			PX4_DEBUG("Unregistered DEV %s", name);
 			ret = PX4_OK;
 			break;
@@ -213,7 +213,7 @@ VDev::unregister_class_devname(const char *class_devname, unsigned class_instanc
 		if (devmap[i] && strcmp(devmap[i]->name, name) == 0) {
 			delete devmap[i];
 			PX4_DEBUG("Unregistered class DEV %s", name);
-			devmap[i] = NULL;
+			devmap[i] = nullptr;
 			pthread_mutex_unlock(&devmutex);
 			return PX4_OK;
 		}
@@ -551,7 +551,7 @@ VDev *VDev::getDev(const char *path)
 
 	pthread_mutex_unlock(&devmutex);
 
-	return NULL;
+	return nullptr;
 }
 
 void VDev::showDevices()
@@ -628,7 +628,7 @@ const char *VDev::topicList(unsigned int *next)
 		}
 	}
 
-	return NULL;
+	return nullptr;
 }
 
 const char *VDev::devList(unsigned int *next)
@@ -639,7 +639,7 @@ const char *VDev::devList(unsigned int *next)
 		}
 	}
 
-	return NULL;
+	return nullptr;
 }
 
 } // namespace device

src/drivers/device/vdev_posix.cpp

@@ -67,7 +67,7 @@ extern "C" {
 	inline bool valid_fd(int fd)
 	{
 		pthread_mutex_lock(&filemutex);
-		bool ret = (fd < PX4_MAX_FD && fd >= 0 && filemap[fd] != NULL);
+		bool ret = (fd < PX4_MAX_FD && fd >= 0 && filemap[fd] != nullptr);
 		pthread_mutex_unlock(&filemutex);
 		return ret;
 	}
@@ -75,7 +75,7 @@ extern "C" {
 	inline VDev *get_vdev(int fd)
 	{
 		pthread_mutex_lock(&filemutex);
-		bool valid = (fd < PX4_MAX_FD && fd >= 0 && filemap[fd] != NULL);
+		bool valid = (fd < PX4_MAX_FD && fd >= 0 && filemap[fd] != nullptr);
 		VDev *dev;
 
 		if (valid) {
@@ -115,7 +115,7 @@ extern "C" {
 			pthread_mutex_lock(&filemutex);
 
 			for (i = 0; i < PX4_MAX_FD; ++i) {
-				if (filemap[i] == 0) {
+				if (filemap[i] == nullptr) {
 					filemap[i] = new device::file_t(flags, dev, i);
 					break;
 				}
@@ -290,7 +290,7 @@ extern "C" {
 		for (i = 0; i < nfds; ++i) {
 			fds[i].sem     = &sem;
 			fds[i].revents = 0;
-			fds[i].priv    = NULL;
+			fds[i].priv    = nullptr;
 
 			VDev *dev = get_vdev(fds[i].fd);
 

src/drivers/gps/gps.cpp

@@ -320,7 +320,7 @@ int GPS::init()
 {
 
 	char gps_num[2] = {(char)('0' + _gps_num), 0};
-	char *const args[2] = { gps_num, NULL };
+	char *const args[2] = { gps_num, nullptr };
 
 	/* start the GPS driver worker task */
 	_task = px4_task_spawn_cmd("gps", SCHED_DEFAULT,

src/drivers/pwm_out_sim/pwm_out_sim.cpp

@@ -191,7 +191,7 @@ PWMSim::PWMSim() :
 	_poll_fds{},
 	_poll_fds_num(0),
 	_armed_sub(-1),
-	_outputs_pub(0),
+	_outputs_pub(nullptr),
 	_num_outputs(0),
 	_primary_pwm_device(false),
 	_groups_required(0),
@@ -487,7 +487,7 @@ PWMSim::task_main()
 			}
 
 			/* do mixing */
-			num_outputs = _mixers->mix(&outputs.output[0], num_outputs, NULL);
+			num_outputs = _mixers->mix(&outputs.output[0], num_outputs, nullptr);
 			outputs.noutputs = num_outputs;
 			outputs.timestamp = hrt_absolute_time();
 
@@ -957,13 +957,13 @@ fake(int argc, char *argv[])
 
 	actuator_controls_s ac;
 
-	ac.control[0] = strtol(argv[1], 0, 0) / 100.0f;
+	ac.control[0] = strtol(argv[1], nullptr, 0) / 100.0f;
 
-	ac.control[1] = strtol(argv[2], 0, 0) / 100.0f;
+	ac.control[1] = strtol(argv[2], nullptr, 0) / 100.0f;
 
-	ac.control[2] = strtol(argv[3], 0, 0) / 100.0f;
+	ac.control[2] = strtol(argv[3], nullptr, 0) / 100.0f;
 
-	ac.control[3] = strtol(argv[4], 0, 0) / 100.0f;
+	ac.control[3] = strtol(argv[4], nullptr, 0) / 100.0f;
 
 	orb_advert_t handle = orb_advertise(ORB_ID_VEHICLE_ATTITUDE_CONTROLS, &ac);
 

src/drivers/vmount/vmount.cpp

@@ -161,7 +161,7 @@ static int vmount_thread_main(int argc, char *argv[])
 
 			for (int i = 0 ; i < 3; ++i) {
 				if (!strcmp(argv[1], axis_names[i])) {
-					long angle_deg = strtol(argv[2], NULL, 0);
+					long angle_deg = strtol(argv[2], nullptr, 0);
 					angles[i] = (float)angle_deg;
 					found_axis = true;
 				}

src/examples/attitude_estimator_ekf/attitude_estimator_ekf_main.cpp

@@ -177,7 +177,7 @@ int attitude_estimator_ekf_main(int argc, char *argv[])
 					      SCHED_PRIORITY_MAX - 5,
 					      7000,
 					      attitude_estimator_ekf_thread_main,
-					      (argv) ? (char * const *)&argv[2] : (char * const *)NULL);
+					      (argv) ? (char * const *)&argv[2] : (char * const *)nullptr);
 		return 0;
 	}
 

src/examples/ekf_att_pos_estimator/ekf_att_pos_estimator_main.cpp

@@ -121,7 +121,7 @@ AttitudePositionEstimatorEKF	*g_estimator = nullptr;
 }
 
 AttitudePositionEstimatorEKF::AttitudePositionEstimatorEKF() :
-	SuperBlock(NULL, "PE"),
+	SuperBlock(nullptr, "PE"),
 	_task_should_exit(false),
 	_task_running(false),
 	_estimator_task(-1),
@@ -396,7 +396,7 @@ int AttitudePositionEstimatorEKF::check_filter_state()
 
 	int check = _ekf->CheckAndBound(&ekf_report);
 
-	const char *const feedback[] = { 0,
+	const char *const feedback[] = { nullptr,
 					 "NaN in states, resetting",
 					 "stale sensor data, resetting",
 					 "got initial position lock",
@@ -1721,7 +1721,7 @@ int ekf_att_pos_estimator_main(int argc, char *argv[])
 	}
 
 	if (!strcmp(argv[1], "debug")) {
-		int debug = strtoul(argv[2], NULL, 10);
+		int debug = strtoul(argv[2], nullptr, 10);
 		int ret = estimator::g_estimator->set_debuglevel(debug);
 
 		return ret;

src/examples/fixedwing_control/main.cpp

@@ -462,7 +462,7 @@ int ex_fixedwing_control_main(int argc, char *argv[])
 						 SCHED_PRIORITY_MAX - 20,
 						 2048,
 						 fixedwing_control_thread_main,
-						 (argv) ? (char *const *)&argv[2] : (char *const *)NULL);
+						 (argv) ? (char *const *)&argv[2] : (char *const *)nullptr);
 		thread_running = true;
 		exit(0);
 	}

src/examples/mc_att_control_multiplatform/mc_att_control_start_nuttx.cpp

@@ -74,7 +74,7 @@ int mc_att_control_m_main(int argc, char *argv[])
 					     SCHED_PRIORITY_MAX - 5,
 					     1900,
 					     mc_att_control_start_main,
-					     (argv) ? (char *const *)&argv[2] : (char *const *)NULL);
+					     (argv) ? (char *const *)&argv[2] : (char *const *)nullptr);
 
 		return 0;
 	}

src/examples/mc_pos_control_multiplatform/mc_pos_control_start_nuttx.cpp

@@ -75,7 +75,7 @@ int mc_pos_control_m_main(int argc, char *argv[])
 					     SCHED_PRIORITY_MAX - 5,
 					     2500,
 					     mc_pos_control_start_main,
-					     (argv) ? (char *const *)&argv[2] : (char *const *)NULL);
+					     (argv) ? (char *const *)&argv[2] : (char *const *)nullptr);
 
 		return 0;
 	}

src/lib/controllib/block/Block.cpp

@@ -57,14 +57,14 @@ Block::Block(SuperBlock *parent, const char *name) :
 	_subscriptions(),
 	_params()
 {
-	if (getParent() != NULL) {
+	if (getParent() != nullptr) {
 		getParent()->getChildren().add(this);
 	}
 }
 
 void Block::getName(char *buf, size_t n)
 {
-	if (getParent() == NULL) {
+	if (getParent() == nullptr) {
 		strncpy(buf, _name, n);
 		// ensure string is terminated
 		buf[n - 1] = '\0';
@@ -89,7 +89,7 @@ void Block::updateParams()
 	BlockParamBase *param = getParams().getHead();
 	int count = 0;
 
-	while (param != NULL) {
+	while (param != nullptr) {
 		if (count++ > maxParamsPerBlock) {
 			char name[blockNameLengthMax];
 			getName(name, blockNameLengthMax);
@@ -108,7 +108,7 @@ void Block::updateSubscriptions()
 	uORB::SubscriptionNode *sub = getSubscriptions().getHead();
 	int count = 0;
 
-	while (sub != NULL) {
+	while (sub != nullptr) {
 		if (count++ > maxSubscriptionsPerBlock) {
 			char name[blockNameLengthMax];
 			getName(name, blockNameLengthMax);
@@ -126,7 +126,7 @@ void Block::updatePublications()
 	uORB::PublicationNode *pub = getPublications().getHead();
 	int count = 0;
 
-	while (pub != NULL) {
+	while (pub != nullptr) {
 		if (count++ > maxPublicationsPerBlock) {
 			char name[blockNameLengthMax];
 			getName(name, blockNameLengthMax);
@@ -145,7 +145,7 @@ void SuperBlock::setDt(float dt)
 	Block *child = getChildren().getHead();
 	int count = 0;
 
-	while (child != NULL) {
+	while (child != nullptr) {
 		if (count++ > maxChildrenPerBlock) {
 			char name[blockNameLengthMax];
 			getName(name, blockNameLengthMax);
@@ -163,7 +163,7 @@ void SuperBlock::updateChildParams()
 	Block *child = getChildren().getHead();
 	int count = 0;
 
-	while (child != NULL) {
+	while (child != nullptr) {
 		if (count++ > maxChildrenPerBlock) {
 			char name[blockNameLengthMax];
 			getName(name, blockNameLengthMax);
@@ -181,7 +181,7 @@ void SuperBlock::updateChildSubscriptions()
 	Block *child = getChildren().getHead();
 	int count = 0;
 
-	while (child != NULL) {
+	while (child != nullptr) {
 		if (count++ > maxChildrenPerBlock) {
 			char name[blockNameLengthMax];
 			getName(name, blockNameLengthMax);
@@ -199,7 +199,7 @@ void SuperBlock::updateChildPublications()
 	Block *child = getChildren().getHead();
 	int count = 0;
 
-	while (child != NULL) {
+	while (child != nullptr) {
 		if (count++ > maxChildrenPerBlock) {
 			char name[blockNameLengthMax];
 			getName(name, blockNameLengthMax);

src/lib/controllib/block/BlockParam.cpp

@@ -53,7 +53,7 @@ BlockParamBase::BlockParamBase(Block *parent, const char *name, bool parent_pref
 {
 	char fullname[blockNameLengthMax];
 
-	if (parent == NULL) {
+	if (parent == nullptr) {
 		strncpy(fullname, name, blockNameLengthMax);
 
 	} else {

src/lib/launchdetection/LaunchDetector.cpp

@@ -45,7 +45,7 @@ namespace launchdetection
 {
 
 LaunchDetector::LaunchDetector() :
-	SuperBlock(NULL, "LAUN"),
+	SuperBlock(nullptr, "LAUN"),
 	activeLaunchDetectionMethodIndex(-1),
 	launchdetection_on(this, "ALL_ON"),
 	throttlePreTakeoff(nullptr, "FW_THR_IDLE")

src/lib/runway_takeoff/RunwayTakeoff.cpp

@@ -52,7 +52,7 @@ namespace runwaytakeoff
 {
 
 RunwayTakeoff::RunwayTakeoff() :
-	SuperBlock(NULL, "RWTO"),
+	SuperBlock(nullptr, "RWTO"),
 	_state(),
 	_initialized(false),
 	_initialized_time(0),

src/modules/commander/commander.cpp

@@ -157,7 +157,7 @@ static constexpr uint8_t COMMANDER_MAX_GPS_NOISE = 60;		/**< Maximum percentage
 #define HIL_ID_MAX 1999
 
 /* Mavlink log uORB handle */
-static orb_advert_t mavlink_log_pub = 0;
+static orb_advert_t mavlink_log_pub = nullptr;
 
 /* System autostart ID */
 static int autostart_id;
@@ -1714,7 +1714,7 @@ int commander_thread_main(int argc, char *argv[])
 	(void)pthread_attr_setschedparam(&commander_low_prio_attr, &param);
 #endif
 
-	pthread_create(&commander_low_prio_thread, &commander_low_prio_attr, commander_low_prio_loop, NULL);
+	pthread_create(&commander_low_prio_thread, &commander_low_prio_attr, commander_low_prio_loop, nullptr);
 	pthread_attr_destroy(&commander_low_prio_attr);
 
 	while (!thread_should_exit) {
@@ -3075,7 +3075,7 @@ int commander_thread_main(int argc, char *argv[])
 	}
 
 	/* wait for threads to complete */
-	ret = pthread_join(commander_low_prio_thread, NULL);
+	ret = pthread_join(commander_low_prio_thread, nullptr);
 
 	if (ret) {
 		warn("join failed: %d", ret);
@@ -4169,5 +4169,5 @@ void *commander_low_prio_loop(void *arg)
 
 	px4_close(cmd_sub);
 
-	return NULL;
+	return nullptr;
 }

src/modules/commander/mag_calibration.cpp

@@ -548,9 +548,9 @@ calibrate_return mag_calibrate_all(orb_advert_t *mavlink_log_pub)
 		worker_data.sub_mag[cur_mag] = -1;
 
 		// Initialize to no memory allocated
-		worker_data.x[cur_mag] = NULL;
-		worker_data.y[cur_mag] = NULL;
-		worker_data.z[cur_mag] = NULL;
+		worker_data.x[cur_mag] = nullptr;
+		worker_data.y[cur_mag] = nullptr;
+		worker_data.z[cur_mag] = nullptr;
 		worker_data.calibration_counter_total[cur_mag] = 0;
 	}
 
@@ -563,7 +563,7 @@ calibrate_return mag_calibrate_all(orb_advert_t *mavlink_log_pub)
 		worker_data.y[cur_mag] = reinterpret_cast<float *>(malloc(sizeof(float) * calibration_points_maxcount));
 		worker_data.z[cur_mag] = reinterpret_cast<float *>(malloc(sizeof(float) * calibration_points_maxcount));
 
-		if (worker_data.x[cur_mag] == NULL || worker_data.y[cur_mag] == NULL || worker_data.z[cur_mag] == NULL) {
+		if (worker_data.x[cur_mag] == nullptr || worker_data.y[cur_mag] == nullptr || worker_data.z[cur_mag] == nullptr) {
 			calibration_log_critical(mavlink_log_pub, "[cal] ERROR: out of memory");
 			result = calibrate_return_error;
 		}

src/modules/commander/state_machine_helper.cpp

@@ -564,7 +564,7 @@ transition_result_t hil_state_transition(hil_state_t new_state, orb_advert_t sta
 				for (;;) {
 					devname = px4_get_device_names(&handle);
 
-					if (devname == NULL) {
+					if (devname == nullptr) {
 						break;
 					}
 

src/modules/controllib_test/controllib_test_main.cpp

@@ -94,7 +94,7 @@ int basicBlocksTest()
 int blockLimitTest()
 {
 	printf("Test BlockLimit\t\t\t: ");
-	BlockLimit limit(NULL, "TEST");
+	BlockLimit limit(nullptr, "TEST");
 	// initial state
 	ASSERT_CL(equal(1.0f, limit.getMax()));
 	ASSERT_CL(equal(-1.0f, limit.getMin()));
@@ -110,7 +110,7 @@ int blockLimitTest()
 int blockLimitSymTest()
 {
 	printf("Test BlockLimitSym\t\t: ");
-	BlockLimitSym limit(NULL, "TEST");
+	BlockLimitSym limit(nullptr, "TEST");
 	// initial state
 	ASSERT_CL(equal(1.0f, limit.getMax()));
 	ASSERT_CL(equal(0.0f, limit.getDt()));
@@ -125,7 +125,7 @@ int blockLimitSymTest()
 int blockLowPassTest()
 {
 	printf("Test BlockLowPass\t\t: ");
-	BlockLowPass lowPass(NULL, "TEST_LP");
+	BlockLowPass lowPass(nullptr, "TEST_LP");
 	// test initial state
 	ASSERT_CL(equal(10.0f, lowPass.getFCut()));
 	ASSERT_CL(equal(0.0f, lowPass.getState()));
@@ -153,7 +153,7 @@ int blockLowPassTest()
 int blockHighPassTest()
 {
 	printf("Test BlockHighPass\t\t: ");
-	BlockHighPass highPass(NULL, "TEST_HP");
+	BlockHighPass highPass(nullptr, "TEST_HP");
 	// test initial state
 	ASSERT_CL(equal(10.0f, highPass.getFCut()));
 	ASSERT_CL(equal(0.0f, highPass.getU()));
@@ -184,7 +184,7 @@ int blockHighPassTest()
 int blockLowPass2Test()
 {
 	printf("Test BlockLowPass2\t\t: ");
-	BlockLowPass2 lowPass(NULL, "TEST_LP", 100);
+	BlockLowPass2 lowPass(nullptr, "TEST_LP", 100);
 	// test initial state
 	ASSERT_CL(equal(10.0f, lowPass.getFCutParam()));
 	ASSERT_CL(equal(0.0f, lowPass.getState()));
@@ -212,7 +212,7 @@ int blockLowPass2Test()
 int blockIntegralTest()
 {
 	printf("Test BlockIntegral\t\t: ");
-	BlockIntegral integral(NULL, "TEST_I");
+	BlockIntegral integral(nullptr, "TEST_I");
 	// test initial state
 	ASSERT_CL(equal(1.0f, integral.getMax()));
 	ASSERT_CL(equal(0.0f, integral.getDt()));
@@ -249,7 +249,7 @@ int blockIntegralTest()
 int blockIntegralTrapTest()
 {
 	printf("Test BlockIntegralTrap\t\t: ");
-	BlockIntegralTrap integral(NULL, "TEST_I");
+	BlockIntegralTrap integral(nullptr, "TEST_I");
 	// test initial state
 	ASSERT_CL(equal(1.0f, integral.getMax()));
 	ASSERT_CL(equal(0.0f, integral.getDt()));
@@ -292,7 +292,7 @@ int blockIntegralTrapTest()
 int blockDerivativeTest()
 {
 	printf("Test BlockDerivative\t\t: ");
-	BlockDerivative derivative(NULL, "TEST_D");
+	BlockDerivative derivative(nullptr, "TEST_D");
 	// test initial state
 	ASSERT_CL(equal(0.0f, derivative.getU()));
 	ASSERT_CL(equal(10.0f, derivative.getLP()));
@@ -315,7 +315,7 @@ int blockDerivativeTest()
 int blockPTest()
 {
 	printf("Test BlockP\t\t\t: ");
-	BlockP blockP(NULL, "TEST_P");
+	BlockP blockP(nullptr, "TEST_P");
 	// test initial state
 	ASSERT_CL(equal(0.2f, blockP.getKP()));
 	ASSERT_CL(equal(0.0f, blockP.getDt()));
@@ -331,7 +331,7 @@ int blockPTest()
 int blockPITest()
 {
 	printf("Test BlockPI\t\t\t: ");
-	BlockPI blockPI(NULL, "TEST");
+	BlockPI blockPI(nullptr, "TEST");
 	// test initial state
 	ASSERT_CL(equal(0.2f, blockPI.getKP()));
 	ASSERT_CL(equal(0.1f, blockPI.getKI()));
@@ -353,7 +353,7 @@ int blockPITest()
 int blockPDTest()
 {
 	printf("Test BlockPD\t\t\t: ");
-	BlockPD blockPD(NULL, "TEST");
+	BlockPD blockPD(nullptr, "TEST");
 	// test initial state
 	ASSERT_CL(equal(0.2f, blockPD.getKP()));
 	ASSERT_CL(equal(0.01f, blockPD.getKD()));
@@ -378,7 +378,7 @@ int blockPDTest()
 int blockPIDTest()
 {
 	printf("Test BlockPID\t\t\t: ");
-	BlockPID blockPID(NULL, "TEST");
+	BlockPID blockPID(nullptr, "TEST");
 	// test initial state
 	ASSERT_CL(equal(0.2f, blockPID.getKP()));
 	ASSERT_CL(equal(0.1f, blockPID.getKI()));
@@ -408,7 +408,7 @@ int blockPIDTest()
 int blockOutputTest()
 {
 	printf("Test BlockOutput\t\t: ");
-	BlockOutput blockOutput(NULL, "TEST");
+	BlockOutput blockOutput(nullptr, "TEST");
 	// test initial state
 	ASSERT_CL(equal(0.0f, blockOutput.getDt()));
 	ASSERT_CL(equal(0.5f, blockOutput.get()));
@@ -431,7 +431,7 @@ int blockRandUniformTest()
 {
 	srand(1234);
 	printf("Test BlockRandUniform\t\t: ");
-	BlockRandUniform blockRandUniform(NULL, "TEST");
+	BlockRandUniform blockRandUniform(nullptr, "TEST");
 	// test initial state
 	ASSERT_CL(equal(0.0f, blockRandUniform.getDt()));
 	ASSERT_CL(equal(-1.0f, blockRandUniform.getMin()));
@@ -457,7 +457,7 @@ int blockRandGaussTest()
 {
 	srand(1234);
 	printf("Test BlockRandGauss\t\t: ");
-	BlockRandGauss blockRandGauss(NULL, "TEST");
+	BlockRandGauss blockRandGauss(nullptr, "TEST");
 	// test initial state
 	ASSERT_CL(equal(0.0f, blockRandGauss.getDt()));
 	ASSERT_CL(equal(1.0f, blockRandGauss.getMean()));
@@ -486,7 +486,7 @@ int blockRandGaussTest()
 int blockStatsTest()
 {
 	printf("Test BlockStats\t\t\t: ");
-	BlockStats<float, 1> stats(NULL, "TEST");
+	BlockStats<float, 1> stats(nullptr, "TEST");
 	ASSERT_CL(equal(0.0f, stats.getMean()(0)));
 	ASSERT_CL(equal(0.0f, stats.getStdDev()(0)));
 	stats.update(matrix::Scalar<float>(1.0f));
@@ -504,7 +504,7 @@ int blockDelayTest()
 {
 	printf("Test BlockDelay\t\t\t: ");
 	using namespace matrix;
-	BlockDelay<float, 2, 1, 3> delay(NULL, "TEST");
+	BlockDelay<float, 2, 1, 3> delay(nullptr, "TEST");
 	Vector2f u1(1, 2);
 	Vector2f y1 = delay.update(u1);
 	ASSERT_CL(equal(y1(0), u1(0)));

src/modules/ekf2/ekf2_main.cpp

@@ -288,7 +288,7 @@ private:
 };
 
 Ekf2::Ekf2():
-	SuperBlock(NULL, "EKF"),
+	SuperBlock(nullptr, "EKF"),
 	_replay_mode(false),
 	_publish_replay_mode(0),
 	_att_pub(nullptr),

src/modules/fw_att_control/fw_att_control_main.cpp

@@ -364,9 +364,9 @@ FixedwingAttitudeControl::FixedwingAttitudeControl() :
 	_actuators_0_pub(nullptr),
 	_actuators_2_pub(nullptr),
 
-	_rates_sp_id(0),
-	_actuators_id(0),
-	_attitude_setpoint_id(0),
+	_rates_sp_id(nullptr),
+	_actuators_id(nullptr),
+	_attitude_setpoint_id(nullptr),
 
 	/* performance counters */
 	_loop_perf(perf_alloc(PC_ELAPSED, "fwa_dt")),

src/modules/fw_pos_control_l1/fw_pos_control_l1_main.cpp

@@ -557,7 +557,7 @@ FixedwingPositionControl::FixedwingPositionControl() :
 	_fw_pos_ctrl_status_pub(nullptr),
 
 	/* publication ID */
-	_attitude_setpoint_id(0),
+	_attitude_setpoint_id(nullptr),
 
 	/* states */
 	_ctrl_state(),

src/modules/local_position_estimator/BlockLocalPositionEstimator.cpp

@@ -20,7 +20,7 @@ static const char *msg_label = "[lpe] ";  // rate of land detector correction
 
 BlockLocalPositionEstimator::BlockLocalPositionEstimator() :
 	// this block has no parent, and has name LPE
-	SuperBlock(NULL, "LPE"),
+	SuperBlock(nullptr, "LPE"),
 	// subscriptions, set rate, add to list
 	_sub_armed(ORB_ID(actuator_armed), 1000 / 2, 0, &getSubscriptions()),
 	_sub_land(ORB_ID(vehicle_land_detected), 1000 / 2, 0, &getSubscriptions()),
@@ -44,8 +44,8 @@ BlockLocalPositionEstimator::BlockLocalPositionEstimator() :
 	_sub_dist2(ORB_ID(distance_sensor), 1000 / 10, 2, &getSubscriptions()),
 	_sub_dist3(ORB_ID(distance_sensor), 1000 / 10, 3, &getSubscriptions()),
 	_dist_subs(),
-	_sub_lidar(NULL),
-	_sub_sonar(NULL),
+	_sub_lidar(nullptr),
+	_sub_sonar(nullptr),
 
 	// publications
 	_pub_lpos(ORB_ID(vehicle_local_position), -1, &getPublications()),
@@ -223,7 +223,7 @@ void BlockLocalPositionEstimator::update()
 	// auto-detect connected rangefinders while not armed
 	bool armedState = _sub_armed.get().armed;
 
-	if (!armedState && (_sub_lidar == NULL || _sub_sonar == NULL)) {
+	if (!armedState && (_sub_lidar == nullptr || _sub_sonar == nullptr)) {
 
 		// detect distance sensors
 		for (int i = 0; i < N_DIST_SUBS; i++) {
@@ -238,13 +238,13 @@ void BlockLocalPositionEstimator::update()
 
 				if (s->get().type == \
 				    distance_sensor_s::MAV_DISTANCE_SENSOR_LASER &&
-				    _sub_lidar == NULL) {
+				    _sub_lidar == nullptr) {
 					_sub_lidar = s;
 					mavlink_and_console_log_info(&mavlink_log_pub, "%sLidar detected with ID %i", msg_label, i);
 
 				} else if (s->get().type == \
 					   distance_sensor_s::MAV_DISTANCE_SENSOR_ULTRASOUND &&
-					   _sub_sonar == NULL) {
+					   _sub_sonar == nullptr) {
 					_sub_sonar = s;
 					mavlink_and_console_log_info(&mavlink_log_pub, "%sSonar detected with ID %i", msg_label, i);
 				}
@@ -302,8 +302,8 @@ void BlockLocalPositionEstimator::update()
 	bool gpsUpdated = (_fusion.get() & FUSE_GPS) && _sub_gps.updated();
 	bool visionUpdated = (_fusion.get() & FUSE_VIS_POS) && _sub_vision_pos.updated();
 	bool mocapUpdated = _sub_mocap.updated();
-	bool lidarUpdated = (_sub_lidar != NULL) && _sub_lidar->updated();
-	bool sonarUpdated = (_sub_sonar != NULL) && _sub_sonar->updated();
+	bool lidarUpdated = (_sub_lidar != nullptr) && _sub_lidar->updated();
+	bool sonarUpdated = (_sub_sonar != nullptr) && _sub_sonar->updated();
 	bool landUpdated = landed()
 			   && ((_timeStamp - _time_last_land) > 1.0e6f / LAND_RATE); // throttle rate
 

src/modules/local_position_estimator/local_position_estimator_main.cpp

@@ -115,7 +115,7 @@ int local_position_estimator_main(int argc, char *argv[])
 						 SCHED_PRIORITY_MAX - 5,
 						 13500,
 						 local_position_estimator_thread_main,
-						 (argv && argc > 2) ? (char *const *) &argv[2] : (char *const *) NULL);
+						 (argv && argc > 2) ? (char *const *) &argv[2] : (char *const *) nullptr);
 		return 0;
 	}
 

src/modules/logger/log_writer_file.cpp

@@ -136,7 +136,7 @@ void LogWriterFile::thread_stop()
 	notify();
 
 	// wait for thread to complete
-	int ret = pthread_join(_thread, NULL);
+	int ret = pthread_join(_thread, nullptr);
 
 	if (ret) {
 		PX4_WARN("join failed: %d", ret);

src/modules/logger/logger.cpp

@@ -268,12 +268,12 @@ void Logger::run_trampoline(int argc, char *argv[])
 
 	int myoptind = 1;
 	int ch;
-	const char *myoptarg = NULL;
+	const char *myoptarg = nullptr;
 
 	while ((ch = px4_getopt(argc, argv, "r:b:etfm:q:", &myoptind, &myoptarg)) != EOF) {
 		switch (ch) {
 		case 'r': {
-				unsigned long r = strtoul(myoptarg, NULL, 10);
+				unsigned long r = strtoul(myoptarg, nullptr, 10);
 
 				if (r <= 0) {
 					r = 1e6;
@@ -288,7 +288,7 @@ void Logger::run_trampoline(int argc, char *argv[])
 			break;
 
 		case 'b': {
-				unsigned long s = strtoul(myoptarg, NULL, 10);
+				unsigned long s = strtoul(myoptarg, nullptr, 10);
 
 				if (s < 1) {
 					s = 1;
@@ -325,7 +325,7 @@ void Logger::run_trampoline(int argc, char *argv[])
 			break;
 
 		case 'q':
-			queue_size = strtoul(myoptarg, NULL, 10);
+			queue_size = strtoul(myoptarg, nullptr, 10);
 
 			if (queue_size == 0) {
 				queue_size = 1;
@@ -586,7 +586,7 @@ int Logger::add_topics_from_file(const char *fname)
 	/* open the topic list file */
 	fp = fopen(fname, "r");
 
-	if (fp == NULL) {
+	if (fp == nullptr) {
 		return -1;
 	}
 
@@ -596,7 +596,7 @@ int Logger::add_topics_from_file(const char *fname)
 		/* get a line, bail on error/EOF */
 		line[0] = '\0';
 
-		if (fgets(line, sizeof(line), fp) == NULL) {
+		if (fgets(line, sizeof(line), fp) == nullptr) {
 			break;
 		}
 

src/modules/mavlink/mavlink_log_handler.cpp

@@ -64,7 +64,7 @@ static const char *kTmpData    = MOUNTPOINT "/$log$.txt";
 
 //-------------------------------------------------------------------
 static bool
-stat_file(const char *file, time_t *date = 0, uint32_t *size = 0)
+stat_file(const char *file, time_t *date = nullptr, uint32_t *size = nullptr)
 {
 	struct stat st;
 
@@ -89,7 +89,7 @@ MavlinkLogHandler::new_instance(Mavlink *mavlink)
 //-------------------------------------------------------------------
 MavlinkLogHandler::MavlinkLogHandler(Mavlink *mavlink)
 	: MavlinkStream(mavlink)
-	, _pLogHandlerHelper(0)
+	, _pLogHandlerHelper(nullptr)
 {
 
 }
@@ -184,7 +184,7 @@ MavlinkLogHandler::_log_request_list(const mavlink_message_t *msg)
 		//-- Is this a new request?
 		if ((request.end - request.start) > _pLogHandlerHelper->log_count) {
 			delete _pLogHandlerHelper;
-			_pLogHandlerHelper = NULL;
+			_pLogHandlerHelper = nullptr;
 		}
 	}
 
@@ -269,7 +269,7 @@ MavlinkLogHandler::_log_request_erase(const mavlink_message_t * /*msg*/)
 	*/
 	if (_pLogHandlerHelper) {
 		delete _pLogHandlerHelper;
-		_pLogHandlerHelper = 0;
+		_pLogHandlerHelper = nullptr;
 	}
 
 	//-- Delete all logs
@@ -305,7 +305,7 @@ MavlinkLogHandler::_log_request_end(const mavlink_message_t * /*msg*/)
 
 	if (_pLogHandlerHelper) {
 		delete _pLogHandlerHelper;
-		_pLogHandlerHelper = 0;
+		_pLogHandlerHelper = nullptr;
 	}
 }
 
@@ -378,7 +378,7 @@ LogListHelper::LogListHelper()
 	, current_log_size(0)
 	, current_log_data_offset(0)
 	, current_log_data_remaining(0)
-	, current_log_filep(0)
+	, current_log_filep(nullptr)
 {
 	_init();
 }
@@ -435,7 +435,7 @@ LogListHelper::open_for_transmit()
 {
 	if (current_log_filep) {
 		::fclose(current_log_filep);
-		current_log_filep = 0;
+		current_log_filep = nullptr;
 	}
 
 	current_log_filep = ::fopen(current_log_filename, "rb");
@@ -605,7 +605,7 @@ LogListHelper::_get_log_time_size(const char *path, const char *file, time_t &da
 				if (sscanf(&file[3], "%u", &u) == 1) {
 					date += (u * 60);
 
-					if (stat_file(path, 0, &size)) {
+					if (stat_file(path, nullptr, &size)) {
 						return true;
 					}
 				}

src/modules/mavlink/mavlink_main.cpp

@@ -1062,7 +1062,7 @@ Mavlink::find_broadcast_address()
 #else
 	// On Linux, we can determine the required size of the
 	// buffer first by providing NULL to ifc_req.
-	ifconf.ifc_req = NULL;
+	ifconf.ifc_req = nullptr;
 	ifconf.ifc_len = 0;
 
 	ret = ioctl(_socket_fd, SIOCGIFCONF, &ifconf);
@@ -1455,7 +1455,7 @@ Mavlink::message_buffer_init(int size)
 
 	int ret;
 
-	if (_message_buffer.data == 0) {
+	if (_message_buffer.data == nullptr) {
 		ret = PX4_ERROR;
 		_message_buffer.size = 0;
 
@@ -1718,7 +1718,7 @@ Mavlink::task_main(int argc, char *argv[])
 	 * set error flag instead */
 	bool err_flag = false;
 	int myoptind = 1;
-	const char *myoptarg = NULL;
+	const char *myoptarg = nullptr;
 #ifdef __PX4_POSIX
 	char *eptr;
 	int temp_int_arg;
@@ -1727,7 +1727,7 @@ Mavlink::task_main(int argc, char *argv[])
 	while ((ch = px4_getopt(argc, argv, "b:r:d:u:o:m:t:fpvwx", &myoptind, &myoptarg)) != EOF) {
 		switch (ch) {
 		case 'b':
-			_baudrate = strtoul(myoptarg, NULL, 10);
+			_baudrate = strtoul(myoptarg, nullptr, 10);
 
 			if (_baudrate < 9600 || _baudrate > 3000000) {
 				warnx("invalid baud rate '%s'", myoptarg);
@@ -1737,7 +1737,7 @@ Mavlink::task_main(int argc, char *argv[])
 			break;
 
 		case 'r':
-			_datarate = strtoul(myoptarg, NULL, 10);
+			_datarate = strtoul(myoptarg, nullptr, 10);
 
 			if (_datarate < 10 || _datarate > MAX_DATA_RATE) {
 				warnx("invalid data rate '%s'", myoptarg);
@@ -1905,7 +1905,7 @@ Mavlink::task_main(int argc, char *argv[])
 	}
 
 	/* initialize send mutex */
-	pthread_mutex_init(&_send_mutex, NULL);
+	pthread_mutex_init(&_send_mutex, nullptr);
 
 	/* if we are passing on mavlink messages, we need to prepare a buffer for this instance */
 	if (_forwarding_on || _ftp_on) {
@@ -1919,7 +1919,7 @@ Mavlink::task_main(int argc, char *argv[])
 		}
 
 		/* initialize message buffer mutex */
-		pthread_mutex_init(&_message_buffer_mutex, NULL);
+		pthread_mutex_init(&_message_buffer_mutex, nullptr);
 	}
 
 	/* Initialize system properties */
@@ -2366,7 +2366,7 @@ Mavlink::task_main(int argc, char *argv[])
 	}
 
 	/* first wait for threads to complete before tearing down anything */
-	pthread_join(_receive_thread, NULL);
+	pthread_join(_receive_thread, nullptr);
 
 	delete _subscribe_to_stream;
 	_subscribe_to_stream = nullptr;

src/modules/mavlink/mavlink_tests/mavlink_ftp_test.cpp

@@ -74,7 +74,7 @@ MavlinkFtpTest::~MavlinkFtpTest()
 void MavlinkFtpTest::_init(void)
 {
 	_expected_seq_number = 0;
-	_ftp_server = new MavlinkFTP(NULL);
+	_ftp_server = new MavlinkFTP(nullptr);
 	_ftp_server->set_unittest_worker(MavlinkFtpTest::receive_message_handler_generic, this);
 
 	_cleanup_microsd();

src/modules/mc_att_control/mc_att_control_main.cpp

@@ -412,8 +412,8 @@ MulticopterAttitudeControl::MulticopterAttitudeControl() :
 	_v_rates_sp_pub(nullptr),
 	_actuators_0_pub(nullptr),
 	_controller_status_pub(nullptr),
-	_rates_sp_id(0),
-	_actuators_id(0),
+	_rates_sp_id(nullptr),
+	_actuators_id(nullptr),
 
 	_actuators_0_circuit_breaker_enabled(false),
 

src/modules/mc_pos_control/mc_pos_control_main.cpp

@@ -385,7 +385,7 @@ MulticopterPositionControl	*g_control;
 }
 
 MulticopterPositionControl::MulticopterPositionControl() :
-	SuperBlock(NULL, "MPC"),
+	SuperBlock(nullptr, "MPC"),
 	_task_should_exit(false),
 	_control_task(-1),
 	_mavlink_log_pub(nullptr),
@@ -405,7 +405,7 @@ MulticopterPositionControl::MulticopterPositionControl() :
 	_att_sp_pub(nullptr),
 	_local_pos_sp_pub(nullptr),
 	_global_vel_sp_pub(nullptr),
-	_attitude_setpoint_id(0),
+	_attitude_setpoint_id(nullptr),
 	_vehicle_status{},
 	_vehicle_land_detected{},
 	_ctrl_state{},

src/modules/navigator/geofence.cpp

@@ -332,14 +332,14 @@ Geofence::loadFromFile(const char *filename)
 	/* open the mixer definition file */
 	fp = fopen(GEOFENCE_FILENAME, "r");
 
-	if (fp == NULL) {
+	if (fp == nullptr) {
 		return PX4_ERROR;
 	}
 
 	/* create geofence points from valid lines and store in DM */
 	for (;;) {
 		/* get a line, bail on error/EOF */
-		if (fgets(line, sizeof(line), fp) == NULL) {
+		if (fgets(line, sizeof(line), fp) == nullptr) {
 			break;
 		}
 

src/modules/navigator/navigator_main.cpp

@@ -100,7 +100,7 @@ Navigator	*g_navigator;
 }
 
 Navigator::Navigator() :
-	SuperBlock(NULL, "NAV"),
+	SuperBlock(nullptr, "NAV"),
 	_task_should_exit(false),
 	_navigator_task(-1),
 	_mavlink_log_pub(nullptr),

src/modules/position_estimator_inav/position_estimator_inav_main.cpp

@@ -153,7 +153,7 @@ int position_estimator_inav_main(int argc, char *argv[])
 		position_estimator_inav_task = px4_task_spawn_cmd("position_estimator_inav",
 					       SCHED_DEFAULT, SCHED_PRIORITY_MAX - 5, 4600,
 					       position_estimator_inav_thread_main,
-					       (argv && argc > 2) ? (char *const *) &argv[2] : (char *const *) NULL);
+					       (argv && argc > 2) ? (char *const *) &argv[2] : (char *const *) nullptr);
 		return 0;
 	}
 
@@ -385,7 +385,7 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 
 	/* advertise */
 	orb_advert_t vehicle_local_position_pub = orb_advertise(ORB_ID(vehicle_local_position), &local_pos);
-	orb_advert_t vehicle_global_position_pub = NULL;
+	orb_advert_t vehicle_global_position_pub = nullptr;
 
 	struct position_estimator_inav_params params;
 	memset(&params, 0, sizeof(params));
@@ -1383,7 +1383,7 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 
 				global_pos.pressure_alt = sensor.baro_alt_meter;
 
-				if (vehicle_global_position_pub == NULL) {
+				if (vehicle_global_position_pub == nullptr) {
 					vehicle_global_position_pub = orb_advertise(ORB_ID(vehicle_global_position), &global_pos);
 
 				} else {

src/modules/simulator/simulator.cpp

@@ -55,7 +55,7 @@ using namespace simulator;
 
 static px4_task_t g_sim_task = -1;
 
-Simulator *Simulator::_instance = NULL;
+Simulator *Simulator::_instance = nullptr;
 
 Simulator *Simulator::getInstance()
 {

src/modules/simulator/simulator_mavlink.cpp

@@ -744,7 +744,7 @@ void Simulator::pollForMAVLinkMessages(bool publish, int udp_port)
 	_vehicle_status_sub = orb_subscribe(ORB_ID(vehicle_status));
 
 	// got data from simulator, now activate the sending thread
-	pthread_create(&sender_thread, &sender_thread_attr, Simulator::sending_trampoline, NULL);
+	pthread_create(&sender_thread, &sender_thread_attr, Simulator::sending_trampoline, nullptr);
 	pthread_attr_destroy(&sender_thread_attr);
 
 	mavlink_status_t udp_status = {};

src/modules/systemlib/battery.cpp

@@ -42,7 +42,7 @@
 #include "battery.h"
 
 Battery::Battery() :
-	SuperBlock(NULL, "BAT"),
+	SuperBlock(nullptr, "BAT"),
 	_param_v_empty(this, "V_EMPTY"),
 	_param_v_full(this, "V_CHARGED"),
 	_param_n_cells(this, "N_CELLS"),

src/modules/systemlib/mixer/mixer_multirotor.cpp

@@ -414,7 +414,7 @@ MultirotorMixer::mix(float *outputs, unsigned space, uint16_t *status_reg)
 	_delta_out_max = 0.0f;
 
 	// Notify saturation status
-	if (status_reg != NULL) {
+	if (status_reg != nullptr) {
 		(*status_reg) = _saturation_status.value;
 	}
 

src/modules/uORB/uORB_tests/uORBTest_UnitTest.cpp

@@ -127,7 +127,7 @@ int uORBTest::UnitTest::pubsublatency_main(void)
 		sprintf(fname, PX4_ROOTFSDIR"/fs/microsd/timings%u.txt", timingsgroup);
 		FILE *f = fopen(fname, "w");
 
-		if (f == NULL) {
+		if (f == nullptr) {
 			warnx("Error opening file!\n");
 			return uORB::ERROR;
 		}
@@ -472,7 +472,7 @@ int uORBTest::UnitTest::test_multi2()
 		orb_data_fd[i] = orb_subscribe_multi(ORB_ID(orb_test_medium_multi), i);
 	}
 
-	char *const args[1] = { NULL };
+	char *const args[1] = { nullptr };
 	int pubsub_task = px4_task_spawn_cmd("uorb_test_multi",
 					     SCHED_DEFAULT,
 					     SCHED_PRIORITY_MAX - 5,
@@ -761,7 +761,7 @@ int uORBTest::UnitTest::test_queue_poll_notify()
 
 	_thread_should_exit = false;
 
-	char *const args[1] = { NULL };
+	char *const args[1] = { nullptr };
 	int pubsub_task = px4_task_spawn_cmd("uorb_test_queue",
 					     SCHED_DEFAULT,
 					     SCHED_PRIORITY_MIN + 5,

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

@@ -388,7 +388,7 @@ ACCELSIM::transfer(uint8_t *send, uint8_t *recv, unsigned len)
 		// Get data from the simulator
 		Simulator *sim = Simulator::getInstance();
 
-		if (sim == NULL) {
+		if (sim == nullptr) {
 			return ENODEV;
 		}
 
@@ -1159,7 +1159,7 @@ accelsim_main(int argc, char *argv[])
 	enum Rotation rotation = ROTATION_NONE;
 	int ret;
 	int myoptind = 1;
-	const char *myoptarg = NULL;
+	const char *myoptarg = nullptr;
 
 	/* jump over start/off/etc and look at options first */
 	while ((ch = px4_getopt(argc, argv, "R:", &myoptind, &myoptarg)) != EOF) {

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

@@ -425,7 +425,7 @@ AirspeedSim::transfer(const uint8_t *send, unsigned send_len, uint8_t *recv, uns
 		// this is equivalent to the collect phase
 		Simulator *sim = Simulator::getInstance();
 
-		if (sim == NULL) {
+		if (sim == nullptr) {
 			PX4_ERR("Error BARO_SIM::transfer no simulator");
 			return -ENODEV;
 		}

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

@@ -620,7 +620,7 @@ BAROSIM::transfer(const uint8_t *send, unsigned send_len, uint8_t *recv, unsigne
 		/* read requested */
 		Simulator *sim = Simulator::getInstance();
 
-		if (sim == NULL) {
+		if (sim == nullptr) {
 			PX4_ERR("Error BAROSIM_DEV::transfer no simulator");
 			return -ENODEV;
 		}
@@ -785,7 +785,7 @@ start()
 
 	if (g_barosim != nullptr && OK != g_barosim->init()) {
 		delete g_barosim;
-		g_barosim = NULL;
+		g_barosim = nullptr;
 		PX4_ERR("bus init failed");
 		return false;
 	}

src/platforms/posix/drivers/rgbledsim/rgbled.cpp

@@ -641,16 +641,16 @@ rgbledsim_main(int argc, char *argv[])
 
 	/* jump over start/off/etc and look at options first */
 	int myoptind = 1;
-	const char *myoptarg = NULL;
+	const char *myoptarg = nullptr;
 
 	while ((ch = px4_getopt(argc, argv, "a:b:", &myoptind, &myoptarg)) != EOF) {
 		switch (ch) {
 		case 'a':
-			rgbledadr = strtol(myoptarg, NULL, 0);
+			rgbledadr = strtol(myoptarg, nullptr, 0);
 			break;
 
 		case 'b':
-			i2cdevice = strtol(myoptarg, NULL, 0);
+			i2cdevice = strtol(myoptarg, nullptr, 0);
 			break;
 
 		default:
@@ -783,9 +783,9 @@ rgbledsim_main(int argc, char *argv[])
 		}
 
 		rgbled_rgbset_t v;
-		v.red   = strtol(argv[2], NULL, 0);
-		v.green = strtol(argv[3], NULL, 0);
-		v.blue  = strtol(argv[4], NULL, 0);
+		v.red   = strtol(argv[2], nullptr, 0);
+		v.green = strtol(argv[3], nullptr, 0);
+		v.blue  = strtol(argv[4], nullptr, 0);
 		ret = h.ioctl(RGBLED_SET_RGB, (unsigned long)&v);
 		ret = h.ioctl(RGBLED_SET_MODE, (unsigned long)RGBLED_MODE_ON);
 		DevMgr::releaseHandle(h);

src/platforms/posix/main.cpp

@@ -159,7 +159,7 @@ static int mkpath(const char *path, mode_t mode)
 	status = 0;
 	pp = copypath;
 
-	while (status == 0 && (sp = strchr(pp, '/')) != 0) {
+	while (status == 0 && (sp = strchr(pp, '/')) != nullptr) {
 		if (sp != pp) {
 			/* Neither root nor double slash in path */
 			*sp = '\0';
@@ -214,7 +214,7 @@ static void run_cmd(const vector<string> &appargs, bool exit_on_fail, bool silen
 			++i;
 		}
 
-		arg[i] = (char *)0;
+		arg[i] = (char *)nullptr;
 
 		int retval = apps[command](i, (char **)arg);
 
@@ -310,9 +310,9 @@ int main(int argc, char **argv)
 	sig_fpe.sa_handler = _SigFpeHandler;
 	sig_fpe.sa_flags = 0;// not SA_RESTART!;
 
-	sigaction(SIGINT, &sig_int, NULL);
+	sigaction(SIGINT, &sig_int, nullptr);
 	//sigaction(SIGTERM, &sig_int, NULL);
-	sigaction(SIGFPE, &sig_fpe, NULL);
+	sigaction(SIGFPE, &sig_fpe, nullptr);
 
 	set_cpu_scaling();
 
@@ -514,7 +514,7 @@ int main(int argc, char **argv)
 		term.c_lflag &= ~ICANON;
 		term.c_lflag &= ~ECHO;
 		tcsetattr(0, TCSANOW, &term);
-		setbuf(stdin, NULL);
+		setbuf(stdin, nullptr);
 
 		while (!_ExitFlag) {
 

src/platforms/posix/px4_layer/px4_posix_tasks.cpp

@@ -108,7 +108,7 @@ static void *entry_adapter(void *ptr)
 	px4_task_exit(0);
 	PX4_DEBUG("After px4_task_exit");
 
-	return NULL;
+	return nullptr;
 }
 
 void
@@ -134,10 +134,10 @@ px4_task_t px4_task_spawn_cmd(const char *name, int scheduler, int priority, int
 	struct sched_param param = {};
 
 	// Calculate argc
-	while (p != (char *)0) {
+	while (p != (char *)nullptr) {
 		p = argv[argc];
 
-		if (p == (char *)0) {
+		if (p == (char *)nullptr) {
 			break;
 		}
 
@@ -165,7 +165,7 @@ px4_task_t px4_task_spawn_cmd(const char *name, int scheduler, int priority, int
 	}
 
 	// Must add NULL at end of argv
-	taskdata->argv[argc] = (char *)0;
+	taskdata->argv[argc] = (char *)nullptr;
 
 	PX4_DEBUG("starting task %s", name);
 
@@ -249,7 +249,7 @@ px4_task_t px4_task_spawn_cmd(const char *name, int scheduler, int priority, int
 
 		if (rv == EPERM) {
 			//printf("WARNING: NOT RUNING AS ROOT, UNABLE TO RUN REALTIME THREADS\n");
-			rv = pthread_create(&taskmap[taskid].pid, NULL, &entry_adapter, (void *) taskdata);
+			rv = pthread_create(&taskmap[taskid].pid, nullptr, &entry_adapter, (void *) taskdata);
 
 			if (rv != 0) {
 				PX4_ERR("px4_task_spawn_cmd: failed to create thread %d %d\n", rv, errno);
@@ -293,7 +293,7 @@ int px4_task_delete(px4_task_t id)
 	if (pthread_self() == pid) {
 		taskmap[id].isused = false;
 		pthread_mutex_unlock(&task_mutex);
-		pthread_exit(0);
+		pthread_exit(nullptr);
 
 	} else {
 		rv = pthread_cancel(pid);

src/systemcmds/motor_ramp/motor_ramp.cpp

@@ -192,7 +192,7 @@ int motor_ramp_main(int argc, char *argv[])
 					      SCHED_PRIORITY_DEFAULT + 40,
 					      2000,
 					      motor_ramp_thread_main,
-					      (argv) ? (char *const *)&argv[2] : (char *const *)NULL);
+					      (argv) ? (char *const *)&argv[2] : (char *const *)nullptr);
 	return 0;
 
 	usage("unrecognized command");

src/systemcmds/tests/test_mixer.cpp

@@ -399,7 +399,7 @@ bool MixerTest::mixerTest()
 
 	/* mix */
 	should_prearm = true;
-	mixed = mixer_group.mix(&outputs[0], output_max, NULL);
+	mixed = mixer_group.mix(&outputs[0], output_max, nullptr);
 
 	pwm_limit_calc(should_arm, should_prearm, mixed, reverse_pwm_mask, r_page_servo_disarmed, r_page_servo_control_min,
 		       r_page_servo_control_max, outputs, r_page_servos, &pwm_limit);
@@ -440,7 +440,7 @@ bool MixerTest::mixerTest()
 	while (hrt_elapsed_time(&starttime) < INIT_TIME_US + RAMP_TIME_US + 2 * sleep_quantum_us) {
 
 		/* mix */
-		mixed = mixer_group.mix(&outputs[0], output_max, NULL);
+		mixed = mixer_group.mix(&outputs[0], output_max, nullptr);
 
 		pwm_limit_calc(should_arm, should_prearm, mixed, reverse_pwm_mask, r_page_servo_disarmed, r_page_servo_control_min,
 			       r_page_servo_control_max, outputs, r_page_servos, &pwm_limit);
@@ -484,7 +484,7 @@ bool MixerTest::mixerTest()
 		}
 
 		/* mix */
-		mixed = mixer_group.mix(&outputs[0], output_max, NULL);
+		mixed = mixer_group.mix(&outputs[0], output_max, nullptr);
 
 		pwm_limit_calc(should_arm, should_prearm, mixed, reverse_pwm_mask, r_page_servo_disarmed, r_page_servo_control_min,
 			       r_page_servo_control_max, outputs, r_page_servos, &pwm_limit);
@@ -512,7 +512,7 @@ bool MixerTest::mixerTest()
 	while (hrt_elapsed_time(&starttime) < 600000) {
 
 		/* mix */
-		mixed = mixer_group.mix(&outputs[0], output_max, NULL);
+		mixed = mixer_group.mix(&outputs[0], output_max, nullptr);
 
 		pwm_limit_calc(should_arm, should_prearm, mixed, reverse_pwm_mask, r_page_servo_disarmed, r_page_servo_control_min,
 			       r_page_servo_control_max, outputs, r_page_servos, &pwm_limit);
@@ -549,7 +549,7 @@ bool MixerTest::mixerTest()
 	while (hrt_elapsed_time(&starttime) < 600000 + RAMP_TIME_US) {
 
 		/* mix */
-		mixed = mixer_group.mix(&outputs[0], output_max, NULL);
+		mixed = mixer_group.mix(&outputs[0], output_max, nullptr);
 
 		pwm_limit_calc(should_arm, should_prearm, mixed, reverse_pwm_mask, r_page_servo_disarmed, r_page_servo_control_min,
 			       r_page_servo_control_max, outputs, r_page_servos, &pwm_limit);