freebsd-dev/sbin/dump/unctime.c

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/*-
* Copyright (c) 1980, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static char sccsid[] = "@(#)unctime.c 8.1 (Berkeley) 6/5/93";
#endif /* not lint */
#include <sys/types.h>
#include <stdio.h>
#include <time.h>
#ifdef __STDC__
#include <stdlib.h>
#include <string.h>
#endif
#ifndef __P
#include <sys/cdefs.h>
#endif
/*
* Convert a ctime(3) format string into a system format date.
* Return the date thus calculated.
*
* Return -1 if the string is not in ctime format.
*/
/*
* Offsets into the ctime string to various parts.
*/
#define E_MONTH 4
#define E_DAY 8
#define E_HOUR 11
#define E_MINUTE 14
#define E_SECOND 17
#define E_YEAR 20
static int dcmp __P((struct tm *, struct tm *));
static time_t emitl __P((struct tm *));
static int lookup __P((char *));
time_t
unctime(str)
char *str;
{
struct tm then;
char dbuf[26];
(void) strncpy(dbuf, str, sizeof(dbuf) - 1);
dbuf[sizeof(dbuf) - 1] = '\0';
dbuf[E_MONTH+3] = '\0';
if ((then.tm_mon = lookup(&dbuf[E_MONTH])) < 0)
return (-1);
then.tm_mday = atoi(&dbuf[E_DAY]);
then.tm_hour = atoi(&dbuf[E_HOUR]);
then.tm_min = atoi(&dbuf[E_MINUTE]);
then.tm_sec = atoi(&dbuf[E_SECOND]);
then.tm_year = atoi(&dbuf[E_YEAR]) - 1900;
return(emitl(&then));
}
static char months[] =
"JanFebMarAprMayJunJulAugSepOctNovDec";
static int
lookup(str)
char *str;
{
register char *cp, *cp2;
for (cp = months, cp2 = str; *cp != '\0'; cp += 3)
if (strncmp(cp, cp2, 3) == 0)
return((cp-months) / 3);
return(-1);
}
/*
* Routine to convert a localtime(3) format date back into
* a system format date.
*
* Use a binary search.
*/
static time_t
emitl(dp)
struct tm *dp;
{
time_t conv;
register int i, bit;
struct tm dcopy;
dcopy = *dp;
dp = &dcopy;
conv = 0;
for (i = 30; i >= 0; i--) {
bit = 1 << i;
conv |= bit;
if (dcmp(localtime(&conv), dp) > 0)
conv &= ~bit;
}
return(conv);
}
/*
* Compare two localtime dates, return result.
*/
#define DECIDE(a) \
if (dp->a > dp2->a) \
return(1); \
if (dp->a < dp2->a) \
return(-1)
static int
dcmp(dp, dp2)
register struct tm *dp, *dp2;
{
DECIDE(tm_year);
DECIDE(tm_mon);
DECIDE(tm_mday);
DECIDE(tm_hour);
DECIDE(tm_min);
DECIDE(tm_sec);
return(0);
}