time_test.cpp

// Avoid warning on the call of _ftime()
#ifdef  _WIN32
#define _CRT_SECURE_NO_WARNINGS

#include "vrpn_Shared.h"
#include <winbase.h>
#include <stdio.h>
#include <math.h>
#include <sys/types.h>
#include <sys/timeb.h>
#include "vrpn_Types.h"

/*
void	get_time_using_GetLocalTime(unsigned long &sec, unsigned long &usec)
{
    SYSTEMTIME	stime;	    // System time in funky structure
    FILETIME	ftime;	    // Time in 100-nsec intervals since Jan 1 1601
    LARGE_INTEGER   tics;   // ftime stored into a 64-bit quantity

    GetLocalTime(&stime);
    SystemTimeToFileTime(&stime, &ftime);
    tics.HighPart = ftime.dwHighDateTime;
    tics.LowPart = ftime.dwLowDateTime;
    sec = (long)( tics.QuadPart / 10000000L );
    usec = (long)( ( tics.QuadPart - ( ((LONGLONG)(sec)) * 10000000L ) ) / 10 );
}
*/

static void	get_time_using_GetLocalTime(unsigned long &sec, unsigned long &usec)
{
    SYSTEMTIME	stime;	    // System time in funky structure
    FILETIME	ftime;	    // Time in 100-nsec intervals since Jan 1 1601
    LARGE_INTEGER   tics;   // ftime stored into a 64-bit quantity

    GetLocalTime(&stime);
    SystemTimeToFileTime(&stime, &ftime);

    // Copy the data into a structure that can be treated as a 64-bit integer
    tics.HighPart = ftime.dwHighDateTime;
    tics.LowPart = ftime.dwLowDateTime;

    // Convert the 64-bit time into seconds and microseconds since July 1 1601
    sec = (long)( tics.QuadPart / 10000000L );
    usec = (long)( ( tics.QuadPart - ( ((LONGLONG)(sec)) * 10000000L ) ) / 10 );

    // Translate the time to be based on January 1, 1970 (_ftime base)
    // The offset here is gotten by using the "time_test" program to report the
    // difference in seconds between the two clocks.
    sec -= 3054524608L;
}

void	get_time_using_ftime(unsigned long &sec, unsigned long &usec)
{
    struct _timeb t;
    _ftime(&t);
    sec = static_cast<unsigned long>(t.time);
    usec = (long)t. millitm * 1000;
}

int main(int argc, char *argv[]) {

    /* XXX Checking how well the two clocks track each other
    unsigned long    lsec, lusec;
    unsigned long    fsec, fusec;
    long    dsec, dusec;
    int	    i;
    for (i = 0; i < 10; i++) {
	get_time_using_GetLocalTime(lsec, lusec);
	get_time_using_ftime(fsec, fusec);
	dsec = lsec - fsec;
	dusec = lusec - fusec;

	printf("L: %u:%u, F: %u:%u, Difference: %u:%ld\n",
	    lsec, lusec, fsec, fusec, dsec, dusec);

	Sleep(1000);
    }
    */

    /* Checking the vrpn_gettimeofday() function for monotonicity and step size */
    struct timeval last_time, this_time;
    double skip;
    vrpn_gettimeofday(&last_time, NULL);
    printf("Should be no further output if things are working\n");
    while (true) {
      vrpn_gettimeofday(&this_time, NULL);
      skip = vrpn_TimevalMsecs(vrpn_TimevalDiff(this_time, last_time));
      if (skip > 50) {
	printf("Skipped forward %lg microseconds\n", skip);
      }
      if (skip < 0) {
	printf("** Backwards %lg microseconds\n", skip);
      }
      if (skip == 0) {
	printf("Twice the same time\n");
      }
      last_time = this_time;
    }

    return 0;
}

#else
#include <stdio.h>
int main(void)
{
	fprintf(stderr,"Program not ported to other than Windows\n");
	return -1;
}
#endif