Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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). |
| 4 | |
| 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. |
| 9 | |
| 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. |
| 14 | |
| 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. */ |
| 19 | |
| 20 | /* |
| 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 |
| 26 | udf_time_to_stamp. |
| 27 | */ |
| 28 | |
| 29 | /* |
| 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 |
| 33 | */ |
| 34 | |
| 35 | #include <linux/types.h> |
| 36 | #include <linux/kernel.h> |
| 37 | #include "udfdecl.h" |
| 38 | |
| 39 | #define EPOCH_YEAR 1970 |
| 40 | |
| 41 | #ifndef __isleap |
| 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)) |
| 46 | #endif |
| 47 | |
| 48 | /* How many days come before each month (0-12). */ |
| 49 | const unsigned short int __mon_yday[2][13] = |
| 50 | { |
| 51 | /* Normal years. */ |
| 52 | { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 }, |
| 53 | /* Leap years. */ |
| 54 | { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 } |
| 55 | }; |
| 56 | |
| 57 | #define MAX_YEAR_SECONDS 69 |
| 58 | #define SPD 0x15180 /*3600*24*/ |
| 59 | #define SPY(y,l,s) (SPD * (365*y+l)+s) |
| 60 | |
| 61 | static time_t year_seconds[MAX_YEAR_SECONDS]= { |
| 62 | /*1970*/ SPY( 0, 0,0), SPY( 1, 0,0), SPY( 2, 0,0), SPY( 3, 1,0), |
| 63 | /*1974*/ SPY( 4, 1,0), SPY( 5, 1,0), SPY( 6, 1,0), SPY( 7, 2,0), |
| 64 | /*1978*/ SPY( 8, 2,0), SPY( 9, 2,0), SPY(10, 2,0), SPY(11, 3,0), |
| 65 | /*1982*/ SPY(12, 3,0), SPY(13, 3,0), SPY(14, 3,0), SPY(15, 4,0), |
| 66 | /*1986*/ SPY(16, 4,0), SPY(17, 4,0), SPY(18, 4,0), SPY(19, 5,0), |
| 67 | /*1990*/ SPY(20, 5,0), SPY(21, 5,0), SPY(22, 5,0), SPY(23, 6,0), |
| 68 | /*1994*/ SPY(24, 6,0), SPY(25, 6,0), SPY(26, 6,0), SPY(27, 7,0), |
| 69 | /*1998*/ SPY(28, 7,0), SPY(29, 7,0), SPY(30, 7,0), SPY(31, 8,0), |
| 70 | /*2002*/ SPY(32, 8,0), SPY(33, 8,0), SPY(34, 8,0), SPY(35, 9,0), |
| 71 | /*2006*/ SPY(36, 9,0), SPY(37, 9,0), SPY(38, 9,0), SPY(39,10,0), |
| 72 | /*2010*/ SPY(40,10,0), SPY(41,10,0), SPY(42,10,0), SPY(43,11,0), |
| 73 | /*2014*/ SPY(44,11,0), SPY(45,11,0), SPY(46,11,0), SPY(47,12,0), |
| 74 | /*2018*/ SPY(48,12,0), SPY(49,12,0), SPY(50,12,0), SPY(51,13,0), |
| 75 | /*2022*/ SPY(52,13,0), SPY(53,13,0), SPY(54,13,0), SPY(55,14,0), |
| 76 | /*2026*/ SPY(56,14,0), SPY(57,14,0), SPY(58,14,0), SPY(59,15,0), |
| 77 | /*2030*/ SPY(60,15,0), SPY(61,15,0), SPY(62,15,0), SPY(63,16,0), |
| 78 | /*2034*/ SPY(64,16,0), SPY(65,16,0), SPY(66,16,0), SPY(67,17,0), |
| 79 | /*2038*/ SPY(68,17,0) |
| 80 | }; |
| 81 | |
| 82 | extern struct timezone sys_tz; |
| 83 | |
| 84 | #define SECS_PER_HOUR (60 * 60) |
| 85 | #define SECS_PER_DAY (SECS_PER_HOUR * 24) |
| 86 | |
| 87 | time_t * |
| 88 | udf_stamp_to_time(time_t *dest, long *dest_usec, kernel_timestamp src) |
| 89 | { |
| 90 | int yday; |
| 91 | uint8_t type = src.typeAndTimezone >> 12; |
| 92 | int16_t offset; |
| 93 | |
| 94 | if (type == 1) |
| 95 | { |
| 96 | offset = src.typeAndTimezone << 4; |
| 97 | /* sign extent offset */ |
| 98 | offset = (offset >> 4); |
| 99 | if (offset == -2047) /* unspecified offset */ |
| 100 | offset = 0; |
| 101 | } |
| 102 | else |
| 103 | offset = 0; |
| 104 | |
| 105 | if ((src.year < EPOCH_YEAR) || |
Adrian Bunk | f59154c | 2005-05-05 16:16:21 -0700 | [diff] [blame^] | 106 | (src.year >= EPOCH_YEAR+MAX_YEAR_SECONDS)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | { |
| 108 | *dest = -1; |
| 109 | *dest_usec = -1; |
| 110 | return NULL; |
| 111 | } |
| 112 | *dest = year_seconds[src.year - EPOCH_YEAR]; |
| 113 | *dest -= offset * 60; |
| 114 | |
| 115 | yday = ((__mon_yday[__isleap (src.year)] |
| 116 | [src.month-1]) + (src.day-1)); |
| 117 | *dest += ( ( (yday* 24) + src.hour ) * 60 + src.minute ) * 60 + src.second; |
| 118 | *dest_usec = src.centiseconds * 10000 + src.hundredsOfMicroseconds * 100 + src.microseconds; |
| 119 | return dest; |
| 120 | } |
| 121 | |
| 122 | |
| 123 | kernel_timestamp * |
| 124 | udf_time_to_stamp(kernel_timestamp *dest, struct timespec ts) |
| 125 | { |
| 126 | long int days, rem, y; |
| 127 | const unsigned short int *ip; |
| 128 | int16_t offset; |
| 129 | |
| 130 | offset = -sys_tz.tz_minuteswest; |
| 131 | |
| 132 | if (!dest) |
| 133 | return NULL; |
| 134 | |
| 135 | dest->typeAndTimezone = 0x1000 | (offset & 0x0FFF); |
| 136 | |
| 137 | ts.tv_sec += offset * 60; |
| 138 | days = ts.tv_sec / SECS_PER_DAY; |
| 139 | rem = ts.tv_sec % SECS_PER_DAY; |
| 140 | dest->hour = rem / SECS_PER_HOUR; |
| 141 | rem %= SECS_PER_HOUR; |
| 142 | dest->minute = rem / 60; |
| 143 | dest->second = rem % 60; |
| 144 | y = 1970; |
| 145 | |
| 146 | #define DIV(a,b) ((a) / (b) - ((a) % (b) < 0)) |
| 147 | #define LEAPS_THRU_END_OF(y) (DIV (y, 4) - DIV (y, 100) + DIV (y, 400)) |
| 148 | |
| 149 | while (days < 0 || days >= (__isleap(y) ? 366 : 365)) |
| 150 | { |
| 151 | long int yg = y + days / 365 - (days % 365 < 0); |
| 152 | |
| 153 | /* Adjust DAYS and Y to match the guessed year. */ |
| 154 | days -= ((yg - y) * 365 |
| 155 | + LEAPS_THRU_END_OF (yg - 1) |
| 156 | - LEAPS_THRU_END_OF (y - 1)); |
| 157 | y = yg; |
| 158 | } |
| 159 | dest->year = y; |
| 160 | ip = __mon_yday[__isleap(y)]; |
| 161 | for (y = 11; days < (long int) ip[y]; --y) |
| 162 | continue; |
| 163 | days -= ip[y]; |
| 164 | dest->month = y + 1; |
| 165 | dest->day = days + 1; |
| 166 | |
| 167 | dest->centiseconds = ts.tv_nsec / 10000000; |
| 168 | dest->hundredsOfMicroseconds = (ts.tv_nsec / 1000 - dest->centiseconds * 10000) / 100; |
| 169 | dest->microseconds = (ts.tv_nsec / 1000 - dest->centiseconds * 10000 - |
| 170 | dest->hundredsOfMicroseconds * 100); |
| 171 | return dest; |
| 172 | } |
| 173 | |
| 174 | /* EOF */ |