freebsd-skq/eBones/kdb_edit/maketime.c

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/*
* Copyright 1990 by the Massachusetts Institute of Technology.
* For copying and distribution information, please see the file
* <Copyright.MIT>.
*
* Convert a struct tm * to a UNIX time.
*
* from: maketime.c,v 4.2 90/01/09 15:54:51 raeburn Exp $
* $Id: maketime.c,v 1.2 1994/07/19 19:23:56 g89r4222 Exp $
*/
#ifndef lint
static char rcsid[] =
"$Id: maketime.c,v 1.1 1994/03/21 16:23:54 piero Exp ";
#endif lint
#include <sys/time.h>
#define daysinyear(y) (((y) % 4) ? 365 : (((y) % 100) ? 366 : (((y) % 400) ? 365 : 366)))
#define SECSPERDAY 24*60*60
#define SECSPERHOUR 60*60
#define SECSPERMIN 60
static int cumdays[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334,
365};
static int leapyear[] = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
static int nonleapyear[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
long
maketime(tp, local)
register struct tm *tp;
int local;
{
register long retval;
int foo;
int *marray;
if (tp->tm_mon < 0 || tp->tm_mon > 11 ||
tp->tm_hour < 0 || tp->tm_hour > 23 ||
tp->tm_min < 0 || tp->tm_min > 59 ||
tp->tm_sec < 0 || tp->tm_sec > 59) /* out of range */
return 0;
retval = 0;
if (tp->tm_year < 1900)
foo = tp->tm_year + 1900;
else
foo = tp->tm_year;
if (foo < 1901 || foo > 2038) /* year is too small/large */
return 0;
if (daysinyear(foo) == 366) {
if (tp->tm_mon > 1)
retval+= SECSPERDAY; /* add leap day */
marray = leapyear;
} else
marray = nonleapyear;
if (tp->tm_mday < 0 || tp->tm_mday > marray[tp->tm_mon])
return 0; /* out of range */
while (--foo >= 1970)
retval += daysinyear(foo) * SECSPERDAY;
retval += cumdays[tp->tm_mon] * SECSPERDAY;
retval += (tp->tm_mday-1) * SECSPERDAY;
retval += tp->tm_hour * SECSPERHOUR + tp->tm_min * SECSPERMIN + tp->tm_sec;
if (local) {
/* need to use local time, so we retrieve timezone info */
struct timezone tz;
struct timeval tv;
if (gettimeofday(&tv, &tz) < 0) {
/* some error--give up? */
return(retval);
}
retval += tz.tz_minuteswest * SECSPERMIN;
}
return(retval);
}