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 to unix time
22 * 10/04/98: added new table-based lookup after seeing how ugly the gnu code is
23 * blf 09/27/99: ripped out all the old code and inserted new table from
24 * John Brockmeyer (without leap second corrections)
25 * rewrote udf_stamp_to_time and fixed timezone accounting in
30 * We don't take into account leap seconds. This may be correct or incorrect.
31 * For more NIST information (especially dealing with leap seconds), see:
32 * http://www.boulder.nist.gov/timefreq/pubs/bulletin/leapsecond.htm
35 #include <linux/types.h>
36 #include <linux/kernel.h>
39 #define EPOCH_YEAR 1970
42 /* Nonzero if YEAR is a leap year (every 4 years,
43 except every 100th isn't, and every 400th is). */
44 #define __isleap(year) \
45 ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
48 /* How many days come before each month (0-12). */
49 static const unsigned short int __mon_yday
[2][13] = {
51 {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365},
53 {0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366}
56 #define MAX_YEAR_SECONDS 69
57 #define SPD 0x15180 /*3600*24 */
58 #define SPY(y,l,s) (SPD * (365*y+l)+s)
60 static time_t year_seconds
[MAX_YEAR_SECONDS
]= {
61 /*1970*/ SPY( 0, 0,0), SPY( 1, 0,0), SPY( 2, 0,0), SPY( 3, 1,0),
62 /*1974*/ SPY( 4, 1,0), SPY( 5, 1,0), SPY( 6, 1,0), SPY( 7, 2,0),
63 /*1978*/ SPY( 8, 2,0), SPY( 9, 2,0), SPY(10, 2,0), SPY(11, 3,0),
64 /*1982*/ SPY(12, 3,0), SPY(13, 3,0), SPY(14, 3,0), SPY(15, 4,0),
65 /*1986*/ SPY(16, 4,0), SPY(17, 4,0), SPY(18, 4,0), SPY(19, 5,0),
66 /*1990*/ SPY(20, 5,0), SPY(21, 5,0), SPY(22, 5,0), SPY(23, 6,0),
67 /*1994*/ SPY(24, 6,0), SPY(25, 6,0), SPY(26, 6,0), SPY(27, 7,0),
68 /*1998*/ SPY(28, 7,0), SPY(29, 7,0), SPY(30, 7,0), SPY(31, 8,0),
69 /*2002*/ SPY(32, 8,0), SPY(33, 8,0), SPY(34, 8,0), SPY(35, 9,0),
70 /*2006*/ SPY(36, 9,0), SPY(37, 9,0), SPY(38, 9,0), SPY(39,10,0),
71 /*2010*/ SPY(40,10,0), SPY(41,10,0), SPY(42,10,0), SPY(43,11,0),
72 /*2014*/ SPY(44,11,0), SPY(45,11,0), SPY(46,11,0), SPY(47,12,0),
73 /*2018*/ SPY(48,12,0), SPY(49,12,0), SPY(50,12,0), SPY(51,13,0),
74 /*2022*/ SPY(52,13,0), SPY(53,13,0), SPY(54,13,0), SPY(55,14,0),
75 /*2026*/ SPY(56,14,0), SPY(57,14,0), SPY(58,14,0), SPY(59,15,0),
76 /*2030*/ SPY(60,15,0), SPY(61,15,0), SPY(62,15,0), SPY(63,16,0),
77 /*2034*/ SPY(64,16,0), SPY(65,16,0), SPY(66,16,0), SPY(67,17,0),
81 extern struct timezone sys_tz
;
83 #define SECS_PER_HOUR (60 * 60)
84 #define SECS_PER_DAY (SECS_PER_HOUR * 24)
86 time_t *udf_stamp_to_time(time_t *dest
, long *dest_usec
, kernel_timestamp src
)
89 uint8_t type
= src
.typeAndTimezone
>> 12;
93 offset
= src
.typeAndTimezone
<< 4;
94 /* sign extent offset */
95 offset
= (offset
>> 4);
96 if (offset
== -2047) /* unspecified offset */
102 if ((src
.year
< EPOCH_YEAR
) ||
103 (src
.year
>= EPOCH_YEAR
+ MAX_YEAR_SECONDS
)) {
108 *dest
= year_seconds
[src
.year
- EPOCH_YEAR
];
109 *dest
-= offset
* 60;
111 yday
= ((__mon_yday
[__isleap (src
.year
)]
112 [src
.month
- 1]) + (src
.day
- 1));
113 *dest
+= ( ( (yday
* 24) + src
.hour
) * 60 + src
.minute
) * 60 + src
.second
;
114 *dest_usec
= src
.centiseconds
* 10000 + src
.hundredsOfMicroseconds
* 100 + src
.microseconds
;
118 kernel_timestamp
*udf_time_to_stamp(kernel_timestamp
* dest
, struct timespec ts
)
120 long int days
, rem
, y
;
121 const unsigned short int *ip
;
124 offset
= -sys_tz
.tz_minuteswest
;
129 dest
->typeAndTimezone
= 0x1000 | (offset
& 0x0FFF);
131 ts
.tv_sec
+= offset
* 60;
132 days
= ts
.tv_sec
/ SECS_PER_DAY
;
133 rem
= ts
.tv_sec
% SECS_PER_DAY
;
134 dest
->hour
= rem
/ SECS_PER_HOUR
;
135 rem
%= SECS_PER_HOUR
;
136 dest
->minute
= rem
/ 60;
137 dest
->second
= rem
% 60;
140 #define DIV(a,b) ((a) / (b) - ((a) % (b) < 0))
141 #define LEAPS_THRU_END_OF(y) (DIV (y, 4) - DIV (y, 100) + DIV (y, 400))
143 while (days
< 0 || days
>= (__isleap(y
) ? 366 : 365)) {
144 long int yg
= y
+ days
/ 365 - (days
% 365 < 0);
146 /* Adjust DAYS and Y to match the guessed year. */
147 days
-= ((yg
- y
) * 365
148 + LEAPS_THRU_END_OF (yg
- 1)
149 - LEAPS_THRU_END_OF (y
- 1));
153 ip
= __mon_yday
[__isleap(y
)];
154 for (y
= 11; days
< (long int)ip
[y
]; --y
)
158 dest
->day
= days
+ 1;
160 dest
->centiseconds
= ts
.tv_nsec
/ 10000000;
161 dest
->hundredsOfMicroseconds
= (ts
.tv_nsec
/ 1000 - dest
->centiseconds
* 10000) / 100;
162 dest
->microseconds
= (ts
.tv_nsec
/ 1000 - dest
->centiseconds
* 10000 -
163 dest
->hundredsOfMicroseconds
* 100);