/* $NetBSD: timexsup.c,v 1.5 2024/08/18 20:47:13 christos Exp $ */

/* $NetBSD: timexsup.c,v 1.5 2024/08/18 20:47:13 christos Exp $ */

/*
* timexsup.c - 'struct timex' support functions
*
* Written by Juergen Perlinger ([email protected]) for the NTP project.
* The contents of 'html/copyright.html' apply.
*/

#include "config.h"
#include <limits.h>
#include <math.h>

#ifdef HAVE_SYS_TIME_H
# include <sys/time.h>
#else
# ifdef HAVE_TIME_H
# include <time.h>
# endif
#endif
#ifdef HAVE_SYS_TIMEX_H
# include <time.h>
# include <sys/timex.h>
#else
# ifdef HAVE_TIMEX_H
# include <timex.h>
# endif
#endif

#include "ntp_types.h"
#include "timexsup.h"

#if defined(MOD_NANO) != defined(STA_NANO)
# warning inconsistent definitions of MOD_NANO vs STA_NANO
#endif

static long
clamp_rounded(
double dval
)
{
/* round */
dval = floor(dval + 0.5);

/* clamp / saturate */
if (dval >= (double)LONG_MAX)
return LONG_MAX;
if (dval <= (double)LONG_MIN)
return LONG_MIN;
return (long)dval;
}

double
dbl_from_var_long(
long lval,
int status
)
{
#ifdef STA_NANO
if (STA_NANO & status) {
return (double)lval * 1e-9;
}
#else
UNUSED_ARG(status);
#endif
return (double)lval * 1e-6;
}

double
dbl_from_usec_long(
long lval
)
{
return (double)lval * 1e-6;
}

long
var_long_from_dbl(
double dval,
unsigned int * modes
)
{
#ifdef MOD_NANO
*modes |= MOD_NANO;
dval *= 1e+9;
#else
UNUSED_ARG(modes);
dval *= 1e+6;
#endif
return clamp_rounded(dval);
}

long
usec_long_from_dbl(
double dval
)
{
return clamp_rounded(dval * 1e+6);
}