blob: 2225d39d636bfde5fbcb950dbde67a90f65f4c8e
| 1 | /* |
| 2 | * ntfstime.h - NTFS time related functions. Originated from the Linux-NTFS project. |
| 3 | * |
| 4 | * Copyright (c) 2005 Anton Altaparmakov |
| 5 | * Copyright (c) 2005 Yura Pakhuchiy |
| 6 | * Copyright (c) 2010 Jean-Pierre Andre |
| 7 | * |
| 8 | * This program/include file is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU General Public License as published |
| 10 | * by the Free Software Foundation; either version 2 of the License, or |
| 11 | * (at your option) any later version. |
| 12 | * |
| 13 | * This program/include file is distributed in the hope that it will be |
| 14 | * useful, but WITHOUT ANY WARRANTY; without even the implied warranty |
| 15 | * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | * GNU General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU General Public License |
| 19 | * along with this program (in the main directory of the NTFS-3G |
| 20 | * distribution in the file COPYING); if not, write to the Free Software |
| 21 | * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 22 | */ |
| 23 | |
| 24 | #ifndef _NTFS_NTFSTIME_H |
| 25 | #define _NTFS_NTFSTIME_H |
| 26 | |
| 27 | #ifdef HAVE_TIME_H |
| 28 | #include <time.h> |
| 29 | #endif |
| 30 | #ifdef HAVE_SYS_STAT_H |
| 31 | #include <sys/stat.h> |
| 32 | #endif |
| 33 | #ifdef HAVE_GETTIMEOFDAY |
| 34 | #include <sys/time.h> |
| 35 | #endif |
| 36 | |
| 37 | #include "types.h" |
| 38 | |
| 39 | /* |
| 40 | * assume "struct timespec" is not defined if st_mtime is not defined |
| 41 | */ |
| 42 | #if !defined(st_mtime) & !defined(__timespec_defined) |
| 43 | /*struct timespec { |
| 44 | time_t tv_sec; |
| 45 | long tv_nsec; |
| 46 | } */; |
| 47 | #endif |
| 48 | |
| 49 | /* |
| 50 | * There are four times more conversions of internal representation |
| 51 | * to ntfs representation than any other conversion, so the most |
| 52 | * efficient internal representation is ntfs representation |
| 53 | * (with low endianness) |
| 54 | */ |
| 55 | typedef sle64 ntfs_time; |
| 56 | |
| 57 | #define NTFS_TIME_OFFSET ((s64)(369 * 365 + 89) * 24 * 3600 * 10000000) |
| 58 | |
| 59 | /** |
| 60 | * ntfs2timespec - Convert an NTFS time to Unix time |
| 61 | * @ntfs_time: An NTFS time in 100ns units since 1601 |
| 62 | * |
| 63 | * NTFS stores times as the number of 100ns intervals since January 1st 1601 at |
| 64 | * 00:00 UTC. This system will not suffer from Y2K problems until ~57000AD. |
| 65 | * |
| 66 | * Return: A Unix time (number of seconds since 1970, and nanoseconds) |
| 67 | */ |
| 68 | static __inline__ struct timespec ntfs2timespec(ntfs_time ntfstime) |
| 69 | { |
| 70 | struct timespec spec; |
| 71 | s64 cputime; |
| 72 | |
| 73 | cputime = sle64_to_cpu(ntfstime); |
| 74 | spec.tv_sec = (cputime - (NTFS_TIME_OFFSET)) / 10000000; |
| 75 | spec.tv_nsec = (cputime - (NTFS_TIME_OFFSET) |
| 76 | - (s64)spec.tv_sec*10000000)*100; |
| 77 | /* force zero nsec for overflowing dates */ |
| 78 | if ((spec.tv_nsec < 0) || (spec.tv_nsec > 999999999)) |
| 79 | spec.tv_nsec = 0; |
| 80 | return (spec); |
| 81 | } |
| 82 | |
| 83 | /** |
| 84 | * timespec2ntfs - Convert Linux time to NTFS time |
| 85 | * @utc_time: Linux time to convert to NTFS |
| 86 | * |
| 87 | * Convert the Linux time @utc_time to its corresponding NTFS time. |
| 88 | * |
| 89 | * Linux stores time in a long at present and measures it as the number of |
| 90 | * 1-second intervals since 1st January 1970, 00:00:00 UTC |
| 91 | * with a separated non-negative nanosecond value |
| 92 | * |
| 93 | * NTFS uses Microsoft's standard time format which is stored in a sle64 and is |
| 94 | * measured as the number of 100 nano-second intervals since 1st January 1601, |
| 95 | * 00:00:00 UTC. |
| 96 | * |
| 97 | * Return: An NTFS time (100ns units since Jan 1601) |
| 98 | */ |
| 99 | static __inline__ ntfs_time timespec2ntfs(struct timespec spec) |
| 100 | { |
| 101 | s64 units; |
| 102 | |
| 103 | units = (s64)spec.tv_sec * 10000000 |
| 104 | + NTFS_TIME_OFFSET + spec.tv_nsec/100; |
| 105 | return (cpu_to_le64(units)); |
| 106 | } |
| 107 | |
| 108 | /* |
| 109 | * Return the current time in ntfs format |
| 110 | */ |
| 111 | |
| 112 | static __inline__ ntfs_time ntfs_current_time(void) |
| 113 | { |
| 114 | struct timespec now; |
| 115 | |
| 116 | #if defined(HAVE_CLOCK_GETTIME) || defined(HAVE_SYS_CLOCK_GETTIME) |
| 117 | clock_gettime(CLOCK_REALTIME, &now); |
| 118 | #elif defined(HAVE_GETTIMEOFDAY) |
| 119 | struct timeval microseconds; |
| 120 | |
| 121 | gettimeofday(µseconds, (struct timezone*)NULL); |
| 122 | now.tv_sec = microseconds.tv_sec; |
| 123 | now.tv_nsec = microseconds.tv_usec*1000; |
| 124 | #else |
| 125 | now.tv_sec = time((time_t*)NULL); |
| 126 | now.tv_nsec = 0; |
| 127 | #endif |
| 128 | return (timespec2ntfs(now)); |
| 129 | } |
| 130 | |
| 131 | #endif /* _NTFS_NTFSTIME_H */ |
| 132 |