1 /* Copyright (C) 1993, 1994, 1995, 1996, 1997 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Paul Eggert (eggert@twinsun.com).
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
10 The GNU C Library 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 GNU
13 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If not,
17 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
21 * dgb 10/02/98: ripped this from glibc source to help convert timestamps
23 * 10/04/98: added new table-based lookup after seeing how ugly
25 * blf 09/27/99: ripped out all the old code and inserted new table from
26 * John Brockmeyer (without leap second corrections)
27 * rewrote udf_stamp_to_time and fixed timezone accounting in
32 * We don't take into account leap seconds. This may be correct or incorrect.
33 * For more NIST information (especially dealing with leap seconds), see:
34 * http://www.boulder.nist.gov/timefreq/pubs/bulletin/leapsecond.htm
39 #include <linux/types.h>
40 #include <linux/kernel.h>
41 #include <linux/time.h>
43 #define EPOCH_YEAR 1970
46 /* Nonzero if YEAR is a leap year (every 4 years,
47 except every 100th isn't, and every 400th is). */
48 #define __isleap(year) \
49 ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
52 /* How many days come before each month (0-12). */
53 static const unsigned short int __mon_yday[2][13] = {
55 {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365},
57 {0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366}
60 #define MAX_YEAR_SECONDS 69
61 #define SPD 0x15180 /*3600*24 */
62 #define SPY(y, l, s) (SPD * (365 * y + l) + s)
64 static time_t year_seconds[MAX_YEAR_SECONDS] = {
65 /*1970*/ SPY(0, 0, 0), SPY(1, 0, 0), SPY(2, 0, 0), SPY(3, 1, 0),
66 /*1974*/ SPY(4, 1, 0), SPY(5, 1, 0), SPY(6, 1, 0), SPY(7, 2, 0),
67 /*1978*/ SPY(8, 2, 0), SPY(9, 2, 0), SPY(10, 2, 0), SPY(11, 3, 0),
68 /*1982*/ SPY(12, 3, 0), SPY(13, 3, 0), SPY(14, 3, 0), SPY(15, 4, 0),
69 /*1986*/ SPY(16, 4, 0), SPY(17, 4, 0), SPY(18, 4, 0), SPY(19, 5, 0),
70 /*1990*/ SPY(20, 5, 0), SPY(21, 5, 0), SPY(22, 5, 0), SPY(23, 6, 0),
71 /*1994*/ SPY(24, 6, 0), SPY(25, 6, 0), SPY(26, 6, 0), SPY(27, 7, 0),
72 /*1998*/ SPY(28, 7, 0), SPY(29, 7, 0), SPY(30, 7, 0), SPY(31, 8, 0),
73 /*2002*/ SPY(32, 8, 0), SPY(33, 8, 0), SPY(34, 8, 0), SPY(35, 9, 0),
74 /*2006*/ SPY(36, 9, 0), SPY(37, 9, 0), SPY(38, 9, 0), SPY(39, 10, 0),
75 /*2010*/ SPY(40, 10, 0), SPY(41, 10, 0), SPY(42, 10, 0), SPY(43, 11, 0),
76 /*2014*/ SPY(44, 11, 0), SPY(45, 11, 0), SPY(46, 11, 0), SPY(47, 12, 0),
77 /*2018*/ SPY(48, 12, 0), SPY(49, 12, 0), SPY(50, 12, 0), SPY(51, 13, 0),
78 /*2022*/ SPY(52, 13, 0), SPY(53, 13, 0), SPY(54, 13, 0), SPY(55, 14, 0),
79 /*2026*/ SPY(56, 14, 0), SPY(57, 14, 0), SPY(58, 14, 0), SPY(59, 15, 0),
80 /*2030*/ SPY(60, 15, 0), SPY(61, 15, 0), SPY(62, 15, 0), SPY(63, 16, 0),
81 /*2034*/ SPY(64, 16, 0), SPY(65, 16, 0), SPY(66, 16, 0), SPY(67, 17, 0),
82 /*2038*/ SPY(68, 17, 0)
86 udf_disk_stamp_to_time(struct timespec *dest, struct timestamp src)
89 u16 typeAndTimezone = le16_to_cpu(src.typeAndTimezone);
90 u16 year = le16_to_cpu(src.year);
91 uint8_t type = typeAndTimezone >> 12;
95 offset = typeAndTimezone << 4;
96 /* sign extent offset */
97 offset = (offset >> 4);
98 if (offset == -2047) /* unspecified offset */
103 if ((year < EPOCH_YEAR) ||
104 (year >= EPOCH_YEAR + MAX_YEAR_SECONDS)) {
107 dest->tv_sec = year_seconds[year - EPOCH_YEAR];
108 dest->tv_sec -= offset * 60;
110 yday = ((__mon_yday[__isleap(year)][src.month - 1]) + src.day - 1);
111 dest->tv_sec += (((yday * 24) + src.hour) * 60 + src.minute) * 60 + src.second;
112 dest->tv_nsec = 1000 * (src.centiseconds * 10000 +
113 src.hundredsOfMicroseconds * 100 + src.microseconds);
118 udf_time_to_disk_stamp(struct timestamp *dest, struct timespec ts)
124 offset = -sys_tz.tz_minuteswest;
129 dest->typeAndTimezone = cpu_to_le16(0x1000 | (offset & 0x0FFF));
131 seconds = ts.tv_sec + offset * 60;
132 time64_to_tm(seconds, 0, &tm);
133 dest->year = cpu_to_le16(tm.tm_year + 1900);
134 dest->month = tm.tm_mon + 1;
135 dest->day = tm.tm_mday;
136 dest->hour = tm.tm_hour;
137 dest->minute = tm.tm_min;
138 dest->second = tm.tm_sec;
139 dest->centiseconds = ts.tv_nsec / 10000000;
140 dest->hundredsOfMicroseconds = (ts.tv_nsec / 1000 -
141 dest->centiseconds * 10000) / 100;
142 dest->microseconds = (ts.tv_nsec / 1000 - dest->centiseconds * 10000 -
143 dest->hundredsOfMicroseconds * 100);