1 /* Written by Richard Levitte (richard@levitte.org) for the OpenSSL
3 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
6 /* ====================================================================
7 * Copyright (c) 2001 The OpenSSL Project. All rights reserved.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in
18 * the documentation and/or other materials provided with the
21 * 3. All advertising materials mentioning features or use of this
22 * software must display the following acknowledgment:
23 * "This product includes software developed by the OpenSSL Project
24 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27 * endorse or promote products derived from this software without
28 * prior written permission. For written permission, please contact
29 * licensing@OpenSSL.org.
31 * 5. Products derived from this software may not be called "OpenSSL"
32 * nor may "OpenSSL" appear in their names without prior written
33 * permission of the OpenSSL Project.
35 * 6. Redistributions of any form whatsoever must retain the following
37 * "This product includes software developed by the OpenSSL Project
38 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51 * OF THE POSSIBILITY OF SUCH DAMAGE.
52 * ====================================================================
54 * This product includes cryptographic software written by Eric Young
55 * (eay@cryptsoft.com). This product includes software written by Tim
56 * Hudson (tjh@cryptsoft.com). */
58 #if !defined(_POSIX_C_SOURCE)
59 #define _POSIX_C_SOURCE 201410L /* for gmtime_r */
62 #include <openssl/time_support.h>
64 #define SECS_PER_DAY (24 * 60 * 60)
66 struct tm *OPENSSL_gmtime(const time_t *time, struct tm *result) {
67 #if defined(OPENSSL_WINDOWS)
68 if (gmtime_s(result, time)) {
73 return gmtime_r(time, result);
77 /* Convert date to and from julian day Uses Fliegel & Van Flandern algorithm */
78 static long date_to_julian(int y, int m, int d) {
79 return (1461 * (y + 4800 + (m - 14) / 12)) / 4 +
80 (367 * (m - 2 - 12 * ((m - 14) / 12))) / 12 -
81 (3 * ((y + 4900 + (m - 14) / 12) / 100)) / 4 + d - 32075;
84 static void julian_to_date(long jd, int *y, int *m, int *d) {
86 long n = (4 * L) / 146097;
89 L = L - (146097 * n + 3) / 4;
90 i = (4000 * (L + 1)) / 1461001;
91 L = L - (1461 * i) / 4 + 31;
93 *d = L - (2447 * j) / 80;
95 *m = j + 2 - (12 * L);
96 *y = 100 * (n - 49) + i + L;
99 /* Convert tm structure and offset into julian day and seconds */
100 static int julian_adj(const struct tm *tm, int off_day, long offset_sec,
101 long *pday, int *psec) {
102 int offset_hms, offset_day;
104 int time_year, time_month, time_day;
105 /* split offset into days and day seconds */
106 offset_day = offset_sec / SECS_PER_DAY;
107 /* Avoid sign issues with % operator */
108 offset_hms = offset_sec - (offset_day * SECS_PER_DAY);
109 offset_day += off_day;
110 /* Add current time seconds to offset */
111 offset_hms += tm->tm_hour * 3600 + tm->tm_min * 60 + tm->tm_sec;
112 /* Adjust day seconds if overflow */
113 if (offset_hms >= SECS_PER_DAY) {
115 offset_hms -= SECS_PER_DAY;
116 } else if (offset_hms < 0) {
118 offset_hms += SECS_PER_DAY;
121 /* Convert date of time structure into a Julian day number. */
123 time_year = tm->tm_year + 1900;
124 time_month = tm->tm_mon + 1;
125 time_day = tm->tm_mday;
127 time_jd = date_to_julian(time_year, time_month, time_day);
129 /* Work out Julian day of new date */
130 time_jd += offset_day;
140 int OPENSSL_gmtime_adj(struct tm *tm, int off_day, long offset_sec) {
141 int time_sec, time_year, time_month, time_day;
144 /* Convert time and offset into julian day and seconds */
145 if (!julian_adj(tm, off_day, offset_sec, &time_jd, &time_sec))
148 /* Convert Julian day back to date */
150 julian_to_date(time_jd, &time_year, &time_month, &time_day);
152 if (time_year < 1900 || time_year > 9999)
155 /* Update tm structure */
157 tm->tm_year = time_year - 1900;
158 tm->tm_mon = time_month - 1;
159 tm->tm_mday = time_day;
161 tm->tm_hour = time_sec / 3600;
162 tm->tm_min = (time_sec / 60) % 60;
163 tm->tm_sec = time_sec % 60;
168 int OPENSSL_gmtime_diff(int *pday, int *psec, const struct tm *from,
169 const struct tm *to) {
170 int from_sec, to_sec, diff_sec;
171 long from_jd, to_jd, diff_day;
173 if (!julian_adj(from, 0, 0, &from_jd, &from_sec)) {
176 if (!julian_adj(to, 0, 0, &to_jd, &to_sec)) {
180 diff_day = to_jd - from_jd;
181 diff_sec = to_sec - from_sec;
182 /* Adjust differences so both positive or both negative */
183 if (diff_day > 0 && diff_sec < 0) {
185 diff_sec += SECS_PER_DAY;
187 if (diff_day < 0 && diff_sec > 0) {
189 diff_sec -= SECS_PER_DAY;
193 *pday = (int)diff_day;