pineapple-src/externals/libressl/crypto/o_time.c
2020-12-28 15:15:37 +00:00

161 lines
5.1 KiB
C
Executable file

/* $OpenBSD: o_time.c,v 1.15 2014/06/12 15:49:27 deraadt Exp $ */
/* Written by Richard Levitte (richard@levitte.org) for the OpenSSL
* project 2001.
*/
/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
* project 2008.
*/
/* ====================================================================
* Copyright (c) 2001 The OpenSSL Project. 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 acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* licensing@OpenSSL.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED 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 OpenSSL PROJECT OR
* ITS 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.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
#include <string.h>
#include "o_time.h"
/* Take a tm structure and add an offset to it. This avoids any OS issues
* with restricted date types and overflows which cause the year 2038
* problem.
*/
#define SECS_PER_DAY (24 * 60 * 60)
static long date_to_julian(int y, int m, int d);
static void julian_to_date(long jd, int *y, int *m, int *d);
int
OPENSSL_gmtime_adj(struct tm *tm, int off_day, long offset_sec)
{
int offset_hms, offset_day;
long time_jd;
int time_year, time_month, time_day;
/* split offset into days and day seconds */
offset_day = offset_sec / SECS_PER_DAY;
/* Avoid sign issues with % operator */
offset_hms = offset_sec - (offset_day * SECS_PER_DAY);
offset_day += off_day;
/* Add current time seconds to offset */
offset_hms += tm->tm_hour * 3600 + tm->tm_min * 60 + tm->tm_sec;
/* Adjust day seconds if overflow */
if (offset_hms >= SECS_PER_DAY) {
offset_day++;
offset_hms -= SECS_PER_DAY;
} else if (offset_hms < 0) {
offset_day--;
offset_hms += SECS_PER_DAY;
}
/* Convert date of time structure into a Julian day number.
*/
time_year = tm->tm_year + 1900;
time_month = tm->tm_mon + 1;
time_day = tm->tm_mday;
time_jd = date_to_julian(time_year, time_month, time_day);
/* Work out Julian day of new date */
time_jd += offset_day;
if (time_jd < 0)
return 0;
/* Convert Julian day back to date */
julian_to_date(time_jd, &time_year, &time_month, &time_day);
if (time_year < 1900 || time_year > 9999)
return 0;
/* Update tm structure */
tm->tm_year = time_year - 1900;
tm->tm_mon = time_month - 1;
tm->tm_mday = time_day;
tm->tm_hour = offset_hms / 3600;
tm->tm_min = (offset_hms / 60) % 60;
tm->tm_sec = offset_hms % 60;
return 1;
}
/* Convert date to and from julian day
* Uses Fliegel & Van Flandern algorithm
*/
static long
date_to_julian(int y, int m, int d)
{
return (1461 * (y + 4800 + (m - 14) / 12)) / 4 +
(367 * (m - 2 - 12 * ((m - 14) / 12))) / 12 -
(3 * ((y + 4900 + (m - 14) / 12) / 100)) / 4 +
d - 32075;
}
static void
julian_to_date(long jd, int *y, int *m, int *d)
{
long L = jd + 68569;
long n = (4 * L) / 146097;
long i, j;
L = L - (146097 * n + 3) / 4;
i = (4000 * (L + 1)) / 1461001;
L = L - (1461 * i) / 4 + 31;
j = (80 * L) / 2447;
*d = L - (2447 * j) / 80;
L = j / 11;
*m = j + 2 - (12 * L);
*y = 100 * (n - 49) + i + L;
}