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1// SPDX-License-Identifier: LGPL-2.0+2/* Copyright (C) 1993, 1994, 1995, 1996, 1997 Free Software Foundation, Inc.3 This file is part of the GNU C Library.4 Contributed by Paul Eggert (eggert@twinsun.com). */5 6/*7 * dgb 10/02/98: ripped this from glibc source to help convert timestamps8 * to unix time9 * 10/04/98: added new table-based lookup after seeing how ugly10 * the gnu code is11 * blf 09/27/99: ripped out all the old code and inserted new table from12 * John Brockmeyer (without leap second corrections)13 * rewrote udf_stamp_to_time and fixed timezone accounting in14 * udf_time_to_stamp.15 */16 17/*18 * We don't take into account leap seconds. This may be correct or incorrect.19 * For more NIST information (especially dealing with leap seconds), see:20 * http://www.boulder.nist.gov/timefreq/pubs/bulletin/leapsecond.htm21 */22 23#include "udfdecl.h"24 25#include <linux/types.h>26#include <linux/kernel.h>27#include <linux/time.h>28 29void30udf_disk_stamp_to_time(struct timespec64 *dest, struct timestamp src)31{32 u16 typeAndTimezone = le16_to_cpu(src.typeAndTimezone);33 u16 year = le16_to_cpu(src.year);34 uint8_t type = typeAndTimezone >> 12;35 int16_t offset;36 37 if (type == 1) {38 offset = typeAndTimezone << 4;39 /* sign extent offset */40 offset = (offset >> 4);41 if (offset == -2047) /* unspecified offset */42 offset = 0;43 } else44 offset = 0;45 46 dest->tv_sec = mktime64(year, src.month, src.day, src.hour, src.minute,47 src.second);48 dest->tv_sec -= offset * 60;49 50 /*51 * Sanitize nanosecond field since reportedly some filesystems are52 * recorded with bogus sub-second values.53 */54 if (src.centiseconds < 100 && src.hundredsOfMicroseconds < 100 &&55 src.microseconds < 100) {56 dest->tv_nsec = 1000 * (src.centiseconds * 10000 +57 src.hundredsOfMicroseconds * 100 + src.microseconds);58 } else {59 dest->tv_nsec = 0;60 }61}62 63void64udf_time_to_disk_stamp(struct timestamp *dest, struct timespec64 ts)65{66 time64_t seconds;67 int16_t offset;68 struct tm tm;69 70 offset = -sys_tz.tz_minuteswest;71 72 dest->typeAndTimezone = cpu_to_le16(0x1000 | (offset & 0x0FFF));73 74 seconds = ts.tv_sec + offset * 60;75 time64_to_tm(seconds, 0, &tm);76 dest->year = cpu_to_le16(tm.tm_year + 1900);77 dest->month = tm.tm_mon + 1;78 dest->day = tm.tm_mday;79 dest->hour = tm.tm_hour;80 dest->minute = tm.tm_min;81 dest->second = tm.tm_sec;82 dest->centiseconds = ts.tv_nsec / 10000000;83 dest->hundredsOfMicroseconds = (ts.tv_nsec / 1000 -84 dest->centiseconds * 10000) / 100;85 dest->microseconds = (ts.tv_nsec / 1000 - dest->centiseconds * 10000 -86 dest->hundredsOfMicroseconds * 100);87}88 89/* EOF */90