summaryrefslogtreecommitdiff
path: root/firmware/libc/mktime.c
blob: 822f12e6e8bf394b59c40ee74e0e66ee387646a9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2002 by Linus Nielsen Feltzing
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/


#include <time.h>
#include "config.h"

/* mktime() code taken from lynx-2.8.5 source, written
 by Philippe De Muyter <phdm@macqel.be> */
time_t mktime(struct tm *t)
{
    short month, year;
    time_t result;
    static int m_to_d[12] =
        {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334};

    month = t->tm_mon;
    year = t->tm_year + month / 12 + 1900;
    month %= 12;
    if (month < 0)
    {
        year -= 1;
        month += 12;
    }
    result = (year - 1970) * 365 + m_to_d[month];
    if (month <= 1)
        year -= 1;
    result += (year - 1968) / 4;
    result -= (year - 1900) / 100;
    result += (year - 1600) / 400;
    result += t->tm_mday;
    result -= 1;
    result *= 24;
    result += t->tm_hour;
    result *= 60;
    result += t->tm_min;
    result *= 60;
    result += t->tm_sec;
    return(result);
}