Abstractions to compile systemlib for Linux and Nuttx

Modified uint32_t casts of pointers to unsigned long for portability.
It otherwise breaks on x86_64.

Added _PX4_IOC to handle the conflice between _IOC on Linux and NuttX.

Removed use of px4::ok() because it cannot be used in a thread based
implementation. Changed to use px4::AppMgr which uses ok() on ROS.

Removed up_cxxinitialize.c from Linux build.

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

src/examples/publisher/publisher_example.cpp

@@ -44,7 +44,7 @@
 using namespace px4;
 
 PublisherExample::PublisherExample() :
-	_n(),
+	_n(mgr),
 	_rc_channels_pub(_n.advertise<px4_rc_channels>()),
 	_v_att_pub(_n.advertise<px4_vehicle_attitude>()),
 	_parameter_update_pub(_n.advertise<px4_parameter_update>())
@@ -55,7 +55,7 @@ int PublisherExample::main()
 {
 	px4::Rate loop_rate(10);
 
-	while (px4::ok()) {
+	while (!mgr.exitRequested()) {
 		loop_rate.sleep();
 		_n.spinOnce();
 

src/examples/publisher/publisher_example.h

@@ -39,6 +39,7 @@
  */
 #pragma once
 #include <px4.h>
+#include <px4_app.h>
 
 class PublisherExample
 {
@@ -48,6 +49,8 @@ public:
 	~PublisherExample() {};
 
 	int main();
+
+	static px4::AppMgr mgr;
 protected:
 	px4::NodeHandle _n;
 	px4::Publisher<px4::px4_rc_channels> *_rc_channels_pub;

src/examples/subscriber/subscriber_example.cpp

@@ -49,7 +49,7 @@ void rc_channels_callback_function(const px4_rc_channels &msg)
 }
 
 SubscriberExample::SubscriberExample() :
-	_n(),
+	_n(_mgr),
 	_p_sub_interv("SUB_INTERV", PARAM_SUB_INTERV_DEFAULT),
 	_p_test_float("SUB_TESTF", PARAM_SUB_TESTF_DEFAULT)
 {

src/examples/subscriber/subscriber_example.h

@@ -51,12 +51,14 @@ public:
 	~SubscriberExample() {};
 
 	void spin() {_n.spin();}
+
 protected:
 	px4::NodeHandle _n;
 	px4::ParameterInt _p_sub_interv;
 	px4::ParameterFloat _p_test_float;
 	px4::Subscriber<px4_rc_channels> *_sub_rc_chan;
 
+	AppMgr _mgr;
 
 	void rc_channels_callback(const px4_rc_channels &msg);
 	void vehicle_attitude_callback(const px4_vehicle_attitude &msg);