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Diffstat (limited to 'fs/udf/udftime.c')
| -rw-r--r-- | fs/udf/udftime.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/fs/udf/udftime.c b/fs/udf/udftime.c new file mode 100644 index 000000000000..c2634bda6b50 --- /dev/null +++ b/fs/udf/udftime.c @@ -0,0 +1,174 @@ +/* Copyright (C) 1993, 1994, 1995, 1996, 1997 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Paul Eggert (eggert@twinsun.com). + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +/* + * dgb 10/02/98: ripped this from glibc source to help convert timestamps to unix time + * 10/04/98: added new table-based lookup after seeing how ugly the gnu code is + * blf 09/27/99: ripped out all the old code and inserted new table from + * John Brockmeyer (without leap second corrections) + * rewrote udf_stamp_to_time and fixed timezone accounting in + udf_time_to_stamp. + */ + +/* + * We don't take into account leap seconds. This may be correct or incorrect. + * For more NIST information (especially dealing with leap seconds), see: + * http://www.boulder.nist.gov/timefreq/pubs/bulletin/leapsecond.htm + */ + +#include <linux/types.h> +#include <linux/kernel.h> +#include "udfdecl.h" + +#define EPOCH_YEAR 1970 + +#ifndef __isleap +/* Nonzero if YEAR is a leap year (every 4 years, + except every 100th isn't, and every 400th is). */ +#define __isleap(year) \ + ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0)) +#endif + +/* How many days come before each month (0-12). */ +const unsigned short int __mon_yday[2][13] = +{ + /* Normal years. */ + { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 }, + /* Leap years. */ + { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 } +}; + +#define MAX_YEAR_SECONDS 69 +#define SPD 0x15180 /*3600*24*/ +#define SPY(y,l,s) (SPD * (365*y+l)+s) + +static time_t year_seconds[MAX_YEAR_SECONDS]= { +/*1970*/ SPY( 0, 0,0), SPY( 1, 0,0), SPY( 2, 0,0), SPY( 3, 1,0), +/*1974*/ SPY( 4, 1,0), SPY( 5, 1,0), SPY( 6, 1,0), SPY( 7, 2,0), +/*1978*/ SPY( 8, 2,0), SPY( 9, 2,0), SPY(10, 2,0), SPY(11, 3,0), +/*1982*/ SPY(12, 3,0), SPY(13, 3,0), SPY(14, 3,0), SPY(15, 4,0), +/*1986*/ SPY(16, 4,0), SPY(17, 4,0), SPY(18, 4,0), SPY(19, 5,0), +/*1990*/ SPY(20, 5,0), SPY(21, 5,0), SPY(22, 5,0), SPY(23, 6,0), +/*1994*/ SPY(24, 6,0), SPY(25, 6,0), SPY(26, 6,0), SPY(27, 7,0), +/*1998*/ SPY(28, 7,0), SPY(29, 7,0), SPY(30, 7,0), SPY(31, 8,0), +/*2002*/ SPY(32, 8,0), SPY(33, 8,0), SPY(34, 8,0), SPY(35, 9,0), +/*2006*/ SPY(36, 9,0), SPY(37, 9,0), SPY(38, 9,0), SPY(39,10,0), +/*2010*/ SPY(40,10,0), SPY(41,10,0), SPY(42,10,0), SPY(43,11,0), +/*2014*/ SPY(44,11,0), SPY(45,11,0), SPY(46,11,0), SPY(47,12,0), +/*2018*/ SPY(48,12,0), SPY(49,12,0), SPY(50,12,0), SPY(51,13,0), +/*2022*/ SPY(52,13,0), SPY(53,13,0), SPY(54,13,0), SPY(55,14,0), +/*2026*/ SPY(56,14,0), SPY(57,14,0), SPY(58,14,0), SPY(59,15,0), +/*2030*/ SPY(60,15,0), SPY(61,15,0), SPY(62,15,0), SPY(63,16,0), +/*2034*/ SPY(64,16,0), SPY(65,16,0), SPY(66,16,0), SPY(67,17,0), +/*2038*/ SPY(68,17,0) +}; + +extern struct timezone sys_tz; + +#define SECS_PER_HOUR (60 * 60) +#define SECS_PER_DAY (SECS_PER_HOUR * 24) + +time_t * +udf_stamp_to_time(time_t *dest, long *dest_usec, kernel_timestamp src) +{ + int yday; + uint8_t type = src.typeAndTimezone >> 12; + int16_t offset; + + if (type == 1) + { + offset = src.typeAndTimezone << 4; + /* sign extent offset */ + offset = (offset >> 4); + if (offset == -2047) /* unspecified offset */ + offset = 0; + } + else + offset = 0; + + if ((src.year < EPOCH_YEAR) || + (src.year > EPOCH_YEAR+MAX_YEAR_SECONDS)) + { + *dest = -1; + *dest_usec = -1; + return NULL; + } + *dest = year_seconds[src.year - EPOCH_YEAR]; + *dest -= offset * 60; + + yday = ((__mon_yday[__isleap (src.year)] + [src.month-1]) + (src.day-1)); + *dest += ( ( (yday* 24) + src.hour ) * 60 + src.minute ) * 60 + src.second; + *dest_usec = src.centiseconds * 10000 + src.hundredsOfMicroseconds * 100 + src.microseconds; + return dest; +} + + +kernel_timestamp * +udf_time_to_stamp(kernel_timestamp *dest, struct timespec ts) +{ + long int days, rem, y; + const unsigned short int *ip; + int16_t offset; + + offset = -sys_tz.tz_minuteswest; + + if (!dest) + return NULL; + + dest->typeAndTimezone = 0x1000 | (offset & 0x0FFF); + + ts.tv_sec += offset * 60; + days = ts.tv_sec / SECS_PER_DAY; + rem = ts.tv_sec % SECS_PER_DAY; + dest->hour = rem / SECS_PER_HOUR; + rem %= SECS_PER_HOUR; + dest->minute = rem / 60; + dest->second = rem % 60; + y = 1970; + +#define DIV(a,b) ((a) / (b) - ((a) % (b) < 0)) +#define LEAPS_THRU_END_OF(y) (DIV (y, 4) - DIV (y, 100) + DIV (y, 400)) + + while (days < 0 || days >= (__isleap(y) ? 366 : 365)) + { + long int yg = y + days / 365 - (days % 365 < 0); + + /* Adjust DAYS and Y to match the guessed year. */ + days -= ((yg - y) * 365 + + LEAPS_THRU_END_OF (yg - 1) + - LEAPS_THRU_END_OF (y - 1)); + y = yg; + } + dest->year = y; + ip = __mon_yday[__isleap(y)]; + for (y = 11; days < (long int) ip[y]; --y) + continue; + days -= ip[y]; + dest->month = y + 1; + dest->day = days + 1; + + dest->centiseconds = ts.tv_nsec / 10000000; + dest->hundredsOfMicroseconds = (ts.tv_nsec / 1000 - dest->centiseconds * 10000) / 100; + dest->microseconds = (ts.tv_nsec / 1000 - dest->centiseconds * 10000 - + dest->hundredsOfMicroseconds * 100); + return dest; +} + +/* EOF */ |