firmware/common/timefuncs.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2002 by Linus Nielsen Feltzing
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21
  22 #include <stdio.h> /* get NULL */
  23 #include "config.h"
  24
  25 #include "kernel.h"
  26 #include "rtc.h"
  27 #include "timefuncs.h"
  28 #include "debug.h"
  29
  30 static struct tm tm;
  31
  32 #if !CONFIG_RTC
  33 static void fill_default_tm(struct tm *tm)
  34 {
  35     tm->tm_sec = 0;
  36     tm->tm_min = 0;
  37     tm->tm_hour = 0;
  38     tm->tm_mday = 1;
  39     tm->tm_mon = 0;
  40     tm->tm_year = 70;
  41     tm->tm_wday = 1;
  42     tm->tm_yday = 0; /* Not implemented for now */
  43     tm->tm_isdst = -1; /* Not implemented for now */
  44 }
  45 #endif /* !CONFIG_RTC */
  46
  47 bool valid_time(const struct tm *tm)
  48 {
  49     if (tm->tm_hour < 0 || tm->tm_hour > 23 ||
  50         tm->tm_sec < 0 || tm->tm_sec > 59 ||
  51         tm->tm_min < 0 || tm->tm_min > 59 ||
  52         tm->tm_year < 100 || tm->tm_year > 199 ||
  53         tm->tm_mon < 0 || tm->tm_mon > 11 ||
  54         tm->tm_wday < 0 || tm->tm_wday > 6 ||
  55         tm->tm_mday < 1 || tm->tm_mday > 31)
  56         return false;
  57     else
  58         return true;
  59 }
  60
  61 struct tm *get_time(void)
  62 {
  63 #if CONFIG_RTC
  64     static long timeout = 0;
  65
  66     /* Don't read the RTC more than once per second */
  67     if (TIME_AFTER(current_tick, timeout))
  68     {
  69         /* Once per second, 1/10th of a second off */
  70         timeout = HZ * (current_tick / HZ + 1) + HZ / 5;
  71         rtc_read_datetime(&tm);
  72
  73         tm.tm_yday = 0; /* Not implemented for now */
  74         tm.tm_isdst = -1; /* Not implemented for now */
  75     }
  76 #else /* No RTC */
  77     fill_default_tm(&tm);
  78 #endif /* RTC */
  79     return &tm;
  80 }
  81
  82 int set_time(const struct tm *tm)
  83 {
  84 #if CONFIG_RTC
  85     int rc;
  86
  87     if (valid_time(tm))
  88     {
  89         rc = rtc_write_datetime(tm);
  90
  91         if (rc < 0)
  92             return -1;
  93         else
  94             return 0;
  95     }
  96     else
  97     {
  98         return -2;
  99     }
 100 #else /* No RTC */
 101     (void)tm;
 102     return 0;
 103 #endif /* RTC */
 104 }
 105
 106 #if CONFIG_RTC
 107 /* mktime() code taken from lynx-2.8.5 source, written
 108  by Philippe De Muyter <phdm@macqel.be> */
 109 time_t mktime(struct tm *t)
 110 {
 111     short month, year;
 112     time_t result;
 113     static int m_to_d[12] =
 114         {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334};
 115
 116     month = t->tm_mon;
 117     year = t->tm_year + month / 12 + 1900;
 118     month %= 12;
 119     if (month < 0)
 120     {
 121         year -= 1;
 122         month += 12;
 123     }
 124     result = (year - 1970) * 365 + (year - 1969) / 4 + m_to_d[month];
 125     result = (year - 1970) * 365 + m_to_d[month];
 126     if (month <= 1)
 127         year -= 1;
 128     result += (year - 1968) / 4;
 129     result -= (year - 1900) / 100;
 130     result += (year - 1600) / 400;
 131     result += t->tm_mday;
 132     result -= 1;
 133     result *= 24;
 134     result += t->tm_hour;
 135     result *= 60;
 136     result += t->tm_min;
 137     result *= 60;
 138     result += t->tm_sec;
 139     return(result);
 140 }
 141 #endif
 142
 143 void set_day_of_week(struct tm *tm)
 144 {
 145     int y=tm->tm_year+1900;
 146     int d=tm->tm_mday;
 147     int m=tm->tm_mon;
 148     static const char mo[] = { 0, 3, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4 };
 149
 150     if(m == 0 || m == 1) y--;
 151     tm->tm_wday = (d + mo[m] + y + y/4 - y/100 + y/400) % 7;
 152 }
 153