added support for the sleep() function to be called under a Win32 env…

…ironment

Signed-off-by: Marcos Paulo Berteli Slomp <mslomp@gmail.com>

examples/tiltdemo.c

@@ -31,28 +31,69 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <time.h>
-#include <unistd.h>
+
+#ifndef _WIN32
+  #include <unistd.h>
+#else
+  // Microsoft Visual C++ does not provide the <unistd.h> header, but most of
+  // its contents can be found within the <stdint.h> header:
+  #include <stdint.h>
+  // except for the UNIX sleep() function that has to be emulated:
+  #include <windows.h>
+  // http://pubs.opengroup.org/onlinepubs/009695399/functions/sleep.html
+  // According to the link above, the semantics of UNIX sleep() is as follows:
+  // "If sleep() returns because the requested time has elapsed, the value
+  //  returned shall be 0. If sleep() returns due to delivery of a signal, the
+  //  return value shall be the "unslept" amount (the requested time minus the
+  //  time actually slept) in seconds."
+  // The following function does not implement the return semantics, but
+  // will do for now... A proper implementation would require Performance
+  // Counters before and after the forward call to the Windows Sleep()...
+  unsigned sleep(unsigned seconds)
+  {
+    Sleep(seconds*1000);  // The Windows Sleep operates on milliseconds
+    return(0);
+  }
+  // Note for MinGW-gcc users: MinGW-gcc also does not provide the UNIX sleep()
+  // function within <unistd.h>, but it does provide usleep(); trivial wrapping
+  // of sleep() aroung usleep() is possible, however the usleep() documentation
+  // (http://docs.hp.com/en/B2355-90682/usleep.2.html) clearly states that:
+  // "The useconds argument must be less than 1,000,000. (...)
+  //  (...) The usleep() function may fail if:
+  //  [EINVAL]
+  //     The time interval specified 1,000,000 or more microseconds."
+  // which means that something like below can be potentially dangerous:
+  // unsigned sleep(unsigned seconds)
+  // {
+  //   usleep(seconds*1000000);  // The usleep operates on microseconds
+  //   return(0);
+  // }
+  // So, it is strongly advised to stick with the _WIN32/_MSC_VER
+  // http://www.xinotes.org/notes/note/439/
+#endif//_WIN32
+
+
 
 /* This is a simple demo. It connects to the kinect and plays with the motor,
    the accelerometers, and the LED. It doesn't do anything with images. And,
-   unlike the other examples, no OpenGL is required! 
-   
+   unlike the other examples, no OpenGL is required!
+
    So, this should serve as the reference example for working with the motor,
    accelerometers, and LEDs.   */
-   
+
 void no_kinect_quit(void)
 {
 	printf("Error: Kinect not connected?\n");
 	exit(1);
 }
-   
+
 int main(int argc, char *argv[])
 {
 	srand(time(0));
 
 	while (1) {
 		// Pick a random tilt and a random LED state
-		int led  = rand() % 6;
+		freenect_led_options led = (freenect_led_options) (rand() % 6); // explicit cast
 		int tilt = (rand() % 30)-15;
 		freenect_raw_tilt_state *state = 0;
 		double dx, dy, dz;
@@ -71,8 +112,8 @@ int main(int argc, char *argv[])
 
 		printf("led[%d] tilt[%d] accel[%lf,%lf,%lf]\n", led, tilt, dx,dy,dz);
 
-		sleep(3);    
+		sleep(3);
 	}
 }
-   
+