contrib/file/src/cdf_time.c

   1 /*-
   2  * Copyright (c) 2008 Christos Zoulas
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  15  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  16  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  17  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  18  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  19  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  20  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  21  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  22  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  23  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  24  * POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 #include "file.h"
  28
  29 #ifndef lint
  30 FILE_RCSID("@(#)$File: cdf_time.c,v 1.8 2009/06/20 20:47:30 christos Exp $")
  31 #endif
  32
  33 #include <time.h>
  34 #ifdef TEST
  35 #include <err.h>
  36 #endif
  37 #include <string.h>
  38
  39 #include "cdf.h"
  40
  41 #define isleap(y) ((((y) % 4) == 0) && \
  42     ((((y) % 100) != 0) || (((y) % 400) == 0)))
  43
  44 static const int mdays[] = {
  45     31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
  46 };
  47
  48 #ifdef __DJGPP__
  49 #define timespec timeval
  50 #define tv_nsec tv_usec
  51 #endif
  52
  53
  54 /*
  55  * Return the number of days between jan 01 1601 and jan 01 of year.
  56  */
  57 static int
  58 cdf_getdays(int year)
  59 {
  60         int days = 0;
  61         int y;
  62
  63         for (y = CDF_BASE_YEAR; y < year; y++)
  64                 days += isleap(y) + 365;
  65
  66         return days;
  67 }
  68
  69 /*
  70  * Return the day within the month
  71  */
  72 static int
  73 cdf_getday(int year, int days)
  74 {
  75         size_t m;
  76
  77         for (m = 0; m < sizeof(mdays) / sizeof(mdays[0]); m++) {
  78                 int sub = mdays[m] + (m == 1 && isleap(year));
  79                 if (days < sub)
  80                         return days;
  81                 days -= sub;
  82         }
  83         return days;
  84 }
  85
  86 /*
  87  * Return the 0...11 month number.
  88  */
  89 static int
  90 cdf_getmonth(int year, int days)
  91 {
  92         size_t m;
  93
  94         for (m = 0; m < sizeof(mdays) / sizeof(mdays[0]); m++) {
  95                 days -= mdays[m];
  96                 if (m == 1 && isleap(year))
  97                         days--;
  98                 if (days <= 0)
  99                         return (int)m;
 100         }
 101         return (int)m;
 102 }
 103
 104 int
 105 cdf_timestamp_to_timespec(struct timespec *ts, cdf_timestamp_t t)
 106 {
 107         struct tm tm;
 108 #ifdef HAVE_STRUCT_TM_TM_ZONE
 109         static char UTC[] = "UTC";
 110 #endif
 111         int rdays;
 112
 113         /* Unit is 100's of nanoseconds */
 114         ts->tv_nsec = (t % CDF_TIME_PREC) * 100;
 115
 116         t /= CDF_TIME_PREC;
 117         tm.tm_sec = (int)(t % 60);
 118         t /= 60;
 119
 120         tm.tm_min = (int)(t % 60);
 121         t /= 60;
 122
 123         tm.tm_hour = (int)(t % 24);
 124         t /= 24;
 125
 126         // XXX: Approx
 127         tm.tm_year = (int)(CDF_BASE_YEAR + (t / 365));
 128
 129         rdays = cdf_getdays(tm.tm_year);
 130         t -= rdays;
 131         tm.tm_mday = cdf_getday(tm.tm_year, (int)t);
 132         tm.tm_mon = cdf_getmonth(tm.tm_year, (int)t);
 133         tm.tm_wday = 0;
 134         tm.tm_yday = 0;
 135         tm.tm_isdst = 0;
 136 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 137         tm.tm_gmtoff = 0;
 138 #endif
 139 #ifdef HAVE_STRUCT_TM_TM_ZONE
 140         tm.tm_zone = UTC;
 141 #endif
 142         tm.tm_year -= 1900;
 143         ts->tv_sec = mktime(&tm);
 144         if (ts->tv_sec == -1) {
 145                 errno = EINVAL;
 146                 return -1;
 147         }
 148         return 0;
 149 }
 150
 151 int
 152 /*ARGSUSED*/
 153 cdf_timespec_to_timestamp(cdf_timestamp_t *t, const struct timespec *ts)
 154 {
 155 #ifndef __lint__
 156         (void)&t;
 157         (void)&ts;
 158 #endif
 159 #ifdef notyet
 160         struct tm tm;
 161         if (gmtime_r(&ts->ts_sec, &tm) == NULL) {
 162                 errno = EINVAL;
 163                 return -1;
 164         }
 165         *t = (ts->ts_nsec / 100) * CDF_TIME_PREC;
 166         *t = tm.tm_sec;
 167         *t += tm.tm_min * 60;
 168         *t += tm.tm_hour * 60 * 60;
 169         *t += tm.tm_mday * 60 * 60 * 24;
 170 #endif
 171         return 0;
 172 }
 173
 174
 175 #ifdef TEST
 176 int
 177 main(int argc, char *argv[])
 178 {
 179         struct timespec ts;
 180         static const cdf_timestamp_t tst = 0x01A5E403C2D59C00ULL;
 181         static const char *ref = "Sat Apr 23 01:30:00 1977";
 182         char *p, *q;
 183
 184         cdf_timestamp_to_timespec(&ts, tst);
 185         p = ctime(&ts.tv_sec);
 186         if ((q = strchr(p, '\n')) != NULL)
 187                 *q = '\0';
 188         if (strcmp(ref, p) != 0)
 189                 errx(1, "Error date %s != %s\n", ref, p);
 190         return 0;
 191 }
 192 #endif