freebsd-skq/crypto/heimdal/lib/asn1/timegm.c
2008-05-07 13:39:42 +00:00

87 lines
2.9 KiB
C

/*
* Copyright (c) 1997 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* 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. Neither the name of the Institute 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 INSTITUTE 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 INSTITUTE 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.
*/
#include "der_locl.h"
RCSID("$Id: timegm.c 21366 2007-06-27 10:06:22Z lha $");
static int
is_leap(unsigned y)
{
y += 1900;
return (y % 4) == 0 && ((y % 100) != 0 || (y % 400) == 0);
}
/*
* This is a simplifed version of timegm(3) that doesn't accept out of
* bound values that timegm(3) normally accepts but those are not
* valid in asn1 encodings.
*/
time_t
_der_timegm (struct tm *tm)
{
static const unsigned ndays[2][12] ={
{31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
{31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}};
time_t res = 0;
unsigned i;
if (tm->tm_year < 0)
return -1;
if (tm->tm_mon < 0 || tm->tm_mon > 11)
return -1;
if (tm->tm_mday < 1 || tm->tm_mday > ndays[is_leap(tm->tm_year)][tm->tm_mon])
return -1;
if (tm->tm_hour < 0 || tm->tm_hour > 23)
return -1;
if (tm->tm_min < 0 || tm->tm_min > 59)
return -1;
if (tm->tm_sec < 0 || tm->tm_sec > 59)
return -1;
for (i = 70; i < tm->tm_year; ++i)
res += is_leap(i) ? 366 : 365;
for (i = 0; i < tm->tm_mon; ++i)
res += ndays[is_leap(tm->tm_year)][i];
res += tm->tm_mday - 1;
res *= 24;
res += tm->tm_hour;
res *= 60;
res += tm->tm_min;
res *= 60;
res += tm->tm_sec;
return res;
}