118 lines
3.3 KiB
C
118 lines
3.3 KiB
C
/* $NetBSD: timing.c,v 1.4 2006/06/11 19:34:21 kardel Exp $ */
|
|
|
|
/* Copyright (C) 1996 N.M. Maclaren
|
|
Copyright (C) 1996 The University of Cambridge
|
|
|
|
This includes all of the code needed to handle the time. It assumes rather
|
|
more than is defined by POSIX, unfortunately. Systems that do not have the
|
|
'X/Open' extensions may need changes. */
|
|
|
|
|
|
|
|
#include "header.h"
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/time.h>
|
|
|
|
#define TIMING
|
|
#include "kludges.h"
|
|
#undef TIMING
|
|
|
|
|
|
|
|
#define MILLION_L 1000000l /* For conversion to/from timeval */
|
|
#define MILLION_D 1.0e6 /* Must be equal to MILLION_L */
|
|
|
|
|
|
|
|
double current_time (double offset) {
|
|
|
|
/* Get the current UTC time in seconds since the Epoch plus an offset (usually
|
|
the time from the beginning of the century to the Epoch!) */
|
|
|
|
struct timeval current;
|
|
|
|
errno = 0;
|
|
if (gettimeofday(¤t,NULL))
|
|
fatal(1,"unable to read current machine/system time",NULL);
|
|
return offset+current.tv_sec+1.0e-6*current.tv_usec;
|
|
}
|
|
|
|
|
|
|
|
time_t convert_time (double value, int *millisecs) {
|
|
|
|
/* Convert the time to the ANSI C form. */
|
|
|
|
time_t result = (time_t)value;
|
|
|
|
if ((*millisecs = (int)(1000.0*(value-result))) >= 1000) {
|
|
*millisecs = 0;
|
|
++result;
|
|
}
|
|
return result;
|
|
}
|
|
|
|
|
|
|
|
void adjust_time (double difference, int immediate, double ignore) {
|
|
|
|
/* Adjust the current UTC time. This is portable, even if struct timeval uses
|
|
an unsigned long for tv_sec. */
|
|
|
|
struct timeval old, new, adjust, previous;
|
|
char text[40];
|
|
long n;
|
|
|
|
/* Start by converting to timeval format. Note that we have to cater for
|
|
negative, unsigned values. */
|
|
|
|
previous.tv_sec = 0; /* XXX gcc */
|
|
previous.tv_usec = 0; /* XXX gcc */
|
|
|
|
if ((n = (long)difference) > difference) --n;
|
|
adjust.tv_sec = n;
|
|
adjust.tv_usec = (long)(MILLION_D*(difference-n));
|
|
errno = 0;
|
|
if (gettimeofday(&old,NULL))
|
|
fatal(1,"unable to read machine/system time",NULL);
|
|
new.tv_sec = old.tv_sec+adjust.tv_sec;
|
|
new.tv_usec = (n = (long)old.tv_usec+(long)adjust.tv_usec);
|
|
if (n < 0) {
|
|
new.tv_usec += MILLION_L;
|
|
--new.tv_sec;
|
|
} else if (n >= MILLION_L) {
|
|
new.tv_usec -= MILLION_L;
|
|
++new.tv_sec;
|
|
}
|
|
|
|
/* Now diagnose the situation if necessary, and perform the dirty deed. */
|
|
|
|
if (verbose > 2)
|
|
fprintf(stderr,
|
|
"Times: old=(%ld,%.6ld) new=(%ld,%.6ld) adjust=(%ld,%.6ld)\n",
|
|
(long)old.tv_sec,(long)old.tv_usec,
|
|
(long)new.tv_sec,(long)new.tv_usec,
|
|
(long)adjust.tv_sec,(long)adjust.tv_usec);
|
|
if (immediate) {
|
|
errno = 0;
|
|
if (settimeofday(&new,NULL))
|
|
fatal(1,"unable to reset current system time",NULL);
|
|
} else {
|
|
previous.tv_sec = 0;
|
|
previous.tv_usec = 0;
|
|
errno = 0;
|
|
if (adjtime(&adjust,&previous))
|
|
fatal(1,"unable to adjust current system time",NULL);
|
|
if (previous.tv_sec != 0 || previous.tv_usec != 0) {
|
|
sprintf(text,"(%ld,%.6ld)",
|
|
(long)previous.tv_sec,(long)previous.tv_usec);
|
|
if (previous.tv_sec+1.0e-6*previous.tv_usec > ignore)
|
|
fatal(0,"outstanding time adjustment %s",text);
|
|
else if (verbose)
|
|
fprintf(stderr,"%s: outstanding time adjustment %s\n",
|
|
argv0,text);
|
|
}
|
|
}
|
|
}
|