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/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2008 Free Software Foundation, Inc.
*
* GRUB 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 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef KERNEL_DATETIME_HEADER
#define KERNEL_DATETIME_HEADER 1
#include <grub/types.h>
#include <grub/err.h>
struct grub_datetime
{
grub_uint16_t year;
grub_uint8_t month;
grub_uint8_t day;
grub_uint8_t hour;
grub_uint8_t minute;
grub_uint8_t second;
};
/* Return date and time. */
#ifdef GRUB_MACHINE_EMU
grub_err_t EXPORT_FUNC(grub_get_datetime) (struct grub_datetime *datetime);
/* Set date and time. */
grub_err_t EXPORT_FUNC(grub_set_datetime) (struct grub_datetime *datetime);
#else
grub_err_t grub_get_datetime (struct grub_datetime *datetime);
/* Set date and time. */
grub_err_t grub_set_datetime (struct grub_datetime *datetime);
#endif
int grub_get_weekday (struct grub_datetime *datetime);
const char *grub_get_weekday_name (struct grub_datetime *datetime);
void grub_unixtime2datetime (grub_int64_t nix,
struct grub_datetime *datetime);
static inline int
grub_datetime2unixtime (const struct grub_datetime *datetime, grub_int64_t *nix)
{
grub_int64_t ret;
int y4, ay;
bool bisextile;
const grub_uint16_t monthssum[12]
= { 0,
31,
31 + 28,
31 + 28 + 31,
31 + 28 + 31 + 30,
31 + 28 + 31 + 30 + 31,
31 + 28 + 31 + 30 + 31 + 30,
31 + 28 + 31 + 30 + 31 + 30 + 31,
31 + 28 + 31 + 30 + 31 + 30 + 31 + 31,
31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30,
31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31,
31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30};
const grub_uint8_t months[12] = {31, 28, 31, 30, 31, 30,
31, 31, 30, 31, 30, 31};
const int SECPERMIN = 60;
const int SECPERHOUR = 60 * SECPERMIN;
const int SECPERDAY = 24 * SECPERHOUR;
const int SECPERYEAR = 365 * SECPERDAY;
const grub_int64_t SECPER4YEARS = 4 * SECPERYEAR + SECPERDAY;
if (datetime->month > 12 || datetime->month < 1)
return 0;
/* Convenience: let's have 3 consecutive non-bissextile years
at the beginning of the epoch. So count from 1973 instead of 1970 */
ret = 3 * SECPERYEAR + SECPERDAY;
/* Transform C divisions and modulos to mathematical ones */
y4 = ((datetime->year - 1) >> 2) - (1973 / 4);
ay = datetime->year - 1973 - 4 * y4;
ret += (grub_int64_t) y4 * SECPER4YEARS;
ret += (grub_int64_t) ay * SECPERYEAR;
/*
* Correct above calculation (which assumes every 4 years is a leap year)
* to remove those "false leap years" that are divisible by 100 but not 400.
* Since this logic starts with seconds since 1973, 15 is used because:
* - (1973 - 1) / 100 = 19 (floor due to integer math)
* - (1973 - 1) / 400 = 4 (floor due to integer math)
* - 19 - 4 - 15 = 0 (we want to start with no "false leap years" at time
* zero of 1973)
*/
ret -= ((datetime->year - 1) / 100 - (datetime->year - 1) / 400 - 15)
* SECPERDAY;
ret += (grub_int64_t) monthssum[datetime->month - 1] * SECPERDAY;
bisextile = (ay == 3
&& (datetime->year % 100 != 0
|| datetime->year % 400 == 0)) ? true : false;
if (bisextile == true && datetime->month >= 3)
ret += SECPERDAY;
ret += (datetime->day - 1) * SECPERDAY;
if ((datetime->day > months[datetime->month - 1]
&& !(bisextile == true && datetime->month == 2 && datetime->day == 29))
|| datetime->day < 1)
return 0;
ret += datetime->hour * SECPERHOUR;
if (datetime->hour > 23)
return 0;
ret += datetime->minute * 60;
if (datetime->minute > 59)
return 0;
ret += datetime->second;
/* Accept leap seconds. */
if (datetime->second > 60)
return 0;
if ((datetime->year > 1980 && ret < 0)
|| (datetime->year < 1960 && ret > 0))
return 0;
*nix = ret;
return 1;
}
#if (defined (__powerpc__) || defined (__sparc__)) && !defined (GRUB_UTIL)
grub_err_t
grub_get_datetime_cmos (struct grub_datetime *datetime);
grub_err_t
grub_set_datetime_cmos (struct grub_datetime *datetime);
#endif
#endif /* ! KERNEL_DATETIME_HEADER */
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