arch/all-pc/boot/grub2-aros/include/grub/datetime.h

   1 /*
   2  *  GRUB  --  GRand Unified Bootloader
   3  *  Copyright (C) 2008  Free Software Foundation, Inc.
   4  *
   5  *  GRUB is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  GRUB is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #ifndef KERNEL_DATETIME_HEADER
  20 #define KERNEL_DATETIME_HEADER  1
  21
  22 #include <grub/types.h>
  23 #include <grub/err.h>
  24
  25 struct grub_datetime
  26 {
  27   grub_uint16_t year;
  28   grub_uint8_t month;
  29   grub_uint8_t day;
  30   grub_uint8_t hour;
  31   grub_uint8_t minute;
  32   grub_uint8_t second;
  33 };
  34
  35 /* Return date and time.  */
  36 #ifdef GRUB_MACHINE_EMU
  37 grub_err_t EXPORT_FUNC(grub_get_datetime) (struct grub_datetime *datetime);
  38
  39 /* Set date and time.  */
  40 grub_err_t EXPORT_FUNC(grub_set_datetime) (struct grub_datetime *datetime);
  41 #else
  42 grub_err_t grub_get_datetime (struct grub_datetime *datetime);
  43
  44 /* Set date and time.  */
  45 grub_err_t grub_set_datetime (struct grub_datetime *datetime);
  46 #endif
  47
  48 int grub_get_weekday (struct grub_datetime *datetime);
  49 const char *grub_get_weekday_name (struct grub_datetime *datetime);
  50
  51 void grub_unixtime2datetime (grub_int32_t nix,
  52                              struct grub_datetime *datetime);
  53
  54 static inline int
  55 grub_datetime2unixtime (const struct grub_datetime *datetime, grub_int32_t *nix)
  56 {
  57   grub_int32_t ret;
  58   int y4, ay;
  59   const grub_uint16_t monthssum[12]
  60     = { 0,
  61         31,
  62         31 + 28,
  63         31 + 28 + 31,
  64         31 + 28 + 31 + 30,
  65         31 + 28 + 31 + 30 + 31,
  66         31 + 28 + 31 + 30 + 31 + 30,
  67         31 + 28 + 31 + 30 + 31 + 30 + 31,
  68         31 + 28 + 31 + 30 + 31 + 30 + 31 + 31,
  69         31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30,
  70         31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31,
  71         31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30};
  72   const grub_uint8_t months[12] = {31, 28, 31, 30, 31, 30,
  73                                    31, 31, 30, 31, 30, 31};
  74   const int SECPERMIN = 60;
  75   const int SECPERHOUR = 60 * SECPERMIN;
  76   const int SECPERDAY = 24 * SECPERHOUR;
  77   const int SECPERYEAR = 365 * SECPERDAY;
  78   const int SECPER4YEARS = 4 * SECPERYEAR + SECPERDAY;
  79
  80   if (datetime->year > 2038 || datetime->year < 1901)
  81     return 0;
  82   if (datetime->month > 12 || datetime->month < 1)
  83     return 0;
  84
  85   /* In the period of validity of unixtime all years divisible by 4
  86      are bissextile*/
  87   /* Convenience: let's have 3 consecutive non-bissextile years
  88      at the beginning of the epoch. So count from 1973 instead of 1970 */
  89   ret = 3 * SECPERYEAR + SECPERDAY;
  90
  91   /* Transform C divisions and modulos to mathematical ones */
  92   y4 = ((datetime->year - 1) >> 2) - (1973 / 4);
  93   ay = datetime->year - 1973 - 4 * y4;
  94   ret += y4 * SECPER4YEARS;
  95   ret += ay * SECPERYEAR;
  96
  97   ret += monthssum[datetime->month - 1] * SECPERDAY;
  98   if (ay == 3 && datetime->month >= 3)
  99     ret += SECPERDAY;
 100
 101   ret += (datetime->day - 1) * SECPERDAY;
 102   if ((datetime->day > months[datetime->month - 1]
 103        && (!ay || datetime->month != 2 || datetime->day != 29))
 104       || datetime->day < 1)
 105     return 0;
 106
 107   ret += datetime->hour * SECPERHOUR;
 108   if (datetime->hour > 23)
 109     return 0;
 110   ret += datetime->minute * 60;
 111   if (datetime->minute > 59)
 112     return 0;
 113
 114   ret += datetime->second;
 115   /* Accept leap seconds.  */
 116   if (datetime->second > 60)
 117     return 0;
 118
 119   if ((datetime->year > 1980 && ret < 0)
 120       || (datetime->year < 1960 && ret > 0))
 121     return 0;
 122   *nix = ret;
 123   return 1;
 124 }
 125
 126 #if (defined (__powerpc__) || defined (__sparc__)) && !defined (GRUB_UTIL)
 127 grub_err_t
 128 grub_get_datetime_cmos (struct grub_datetime *datetime);
 129 grub_err_t
 130 grub_set_datetime_cmos (struct grub_datetime *datetime);
 131 #endif
 132
 133 #endif /* ! KERNEL_DATETIME_HEADER */