/* BSD time routines */
/* this should probably live in libc */

/*
 *------------------------------------------------------------------
 *
 * $Source: /u1/jis/gw/cgw/src/sys/libc/RCS/bsd_time.c,v $
 * $Revision: 1.1 $
 * $Date: 89/03/22 16:53:00 $
 * $State: Exp $
 * $Author: jon $
 * $Locker:  $
 *
 * $Log:	bsd_time.c,v $
 * Revision 1.1  89/03/22  16:53:00  jon
 * Initial revision
 * 
 *------------------------------------------------------------------
 */

#ifndef lint
static char *rcsid_bsd_time_c = "$Header: bsd_time.c,v 1.1 89/03/22 16:53:00 jon Exp $";
#endif	lint

/*
 * Copyright (c) 1987 Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Arthur Olson.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)ctime.c	5.14 (Berkeley) 7/6/88";
#endif /* LIBC_SCCS and not lint */

#include "bsd_time.h"

#ifdef CGW
#define tm_mon tm_month
#define tm_min tm_minute
#define tm_sec tm_second 
#endif

char *
asctime(timeptr)
register struct tm *	timeptr;
{
	static char	wday_name[DAYS_PER_WEEK][3] = {
		"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
	};
	static char	mon_name[MONS_PER_YEAR][3] = {
		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
	};
	static char	result[26];

#ifdef CGW
	(void) snprintf(sizeof (result), result, "%.3s %.3s%3d %02d:%02d:%02d %d",
#else
	(void) snprintf(sizeof (result), result, "%.3s %.3s%3d %02d:%02d:%02d %d\n",
#endif
		wday_name[timeptr->tm_wday],
		mon_name[timeptr->tm_mon],
		timeptr->tm_mday, timeptr->tm_hour,
		timeptr->tm_min, timeptr->tm_sec,
		TM_YEAR_BASE + timeptr->tm_year);
	return result;
}

#ifndef TRUE
#define TRUE		1
#define FALSE		0
#endif /* !TRUE */

static int	mon_lengths[2][MONS_PER_YEAR] = {
	31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31,
	31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};

static int	year_lengths[2] = {
	DAYS_PER_NYEAR, DAYS_PER_LYEAR
};

struct tm *
#ifdef CGW
localtime(clock)
unsigned long *	clock;
#else 
offtime(clock, offset)
time_t *  clock;
long		offset;
#endif

{
	register struct tm *	tmp;
	register long		days;
	register long		rem;
	register int		y;
	register int		yleap;
	register int *		ip;
	static struct tm	tm;
#ifdef CGW
#define offset time_zone_offset
	extern long time_zone_offset;
#endif

	tmp = &tm;
	days = *clock / SECS_PER_DAY;
	rem = *clock % SECS_PER_DAY;
	rem += offset;
	while (rem < 0) {
		rem += SECS_PER_DAY;
		--days;
	}
	while (rem >= SECS_PER_DAY) {
		rem -= SECS_PER_DAY;
		++days;
	}
	tmp->tm_hour = (int) (rem / SECS_PER_HOUR);
	rem = rem % SECS_PER_HOUR;
	tmp->tm_min = (int) (rem / SECS_PER_MIN);
	tmp->tm_sec = (int) (rem % SECS_PER_MIN);
	tmp->tm_wday = (int) ((EPOCH_WDAY + days) % DAYS_PER_WEEK);
	if (tmp->tm_wday < 0)
		tmp->tm_wday += DAYS_PER_WEEK;
	y = EPOCH_YEAR;
	if (days >= 0)
		for ( ; ; ) {
			yleap = isleap(y);
			if (days < (long) year_lengths[yleap])
				break;
			++y;
			days = days - (long) year_lengths[yleap];
		}
	else do {
		--y;
		yleap = isleap(y);
		days = days + (long) year_lengths[yleap];
	} while (days < 0);
	tmp->tm_year = y - TM_YEAR_BASE;
	tmp->tm_yday = (int) days;
	ip = mon_lengths[yleap];
	for (tmp->tm_mon = 0; days >= (long) ip[tmp->tm_mon]; ++(tmp->tm_mon))
		days = days - (long) ip[tmp->tm_mon];
	tmp->tm_mday = (int) (days + 1);
	tmp->tm_isdst = 0;
	tmp->tm_zone = "";
	tmp->tm_gmtoff = offset;
	return tmp;
}