fastjar/dostime.c

   1 /*
   2   dostime.c - routines for converting UNIX time to MS-DOS time.
   3
   4   Borrowed from Info-zip's unzip
   5
   6   Copyright (C) 1999 Bryan Burns
   7
   8   This program is free software; you can redistribute it and/or
   9   modify it under the terms of the GNU General Public License
  10   as published by the Free Software Foundation; either version 2
  11   of the License, or (at your option) any later version.
  12
  13   This program is distributed in the hope that it will be useful,
  14   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15   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; if not, write to the Free Software
  20   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  21 */
  22
  23 /* $Id: dostime.c,v 1.1 2000/12/09 03:08:23 apbianco Exp $
  24
  25    $Log: dostime.c,v $
  26    Revision 1.1  2000/12/09 03:08:23  apbianco
  27    2000-12-08  Alexandre Petit-Bianco  <apbianco@cygnus.com>
  28
  29            * fastjar: Imported.
  30
  31    Revision 1.1.1.1  1999/12/06 03:09:12  toast
  32    initial checkin..
  33
  34
  35
  36    Revision 1.6  1999/05/10 08:32:26  burnsbr
  37    added dos2unixtime
  38
  39    Revision 1.5  1999/04/27 10:03:50  burnsbr
  40    configure support
  41
  42    Revision 1.4  1999/04/26 21:55:19  burnsbr
  43    switched from sys/time.h to time.h for better portability
  44
  45    Revision 1.3  1999/04/20 08:54:30  burnsbr
  46    added GPL comment
  47
  48    Revision 1.2  1999/04/20 05:10:53  burnsbr
  49    added RCS tags
  50
  51
  52 */
  53 #include "config.h"
  54
  55 #ifdef TM_IN_SYS_TIME
  56 #include <sys/time.h>
  57 #else
  58 #include <time.h>
  59 #endif
  60
  61 #include "dostime.h"
  62
  63 /*
  64
  65  Copyright (C) 1990-1997 Mark Adler, Richard B. Wales, Jean-loup Gailly,
  66  Kai Uwe Rommel, Onno van der Linden and Igor Mandrichenko.
  67  Permission is granted to any individual or institution to use, copy, or
  68  redistribute this software so long as all of the original files are included,
  69  that it is not sold for profit, and that this copyright notice is retained.
  70
  71 */
  72
  73
  74 time_t dos2unixtime(dostime)
  75      unsigned long dostime;            /* DOS time to convert */
  76      /* Return the Unix time_t value (GMT/UTC time) for the DOS format (local)
  77       * time dostime, where dostime is a four byte value (date in most
  78       * significant word, time in least significant word), see dostime()
  79       * function.
  80       */
  81 {
  82   struct tm *t;         /* argument for mktime() */
  83   time_t clock = time(NULL);
  84
  85   t = localtime(&clock);
  86   t->tm_isdst = -1;     /* let mktime() determine if DST is in effect */
  87   /* Convert DOS time to UNIX time_t format */
  88   t->tm_sec  = (((int)dostime) <<  1) & 0x3e;
  89   t->tm_min  = (((int)dostime) >>  5) & 0x3f;
  90   t->tm_hour = (((int)dostime) >> 11) & 0x1f;
  91   t->tm_mday = (int)(dostime >> 16) & 0x1f;
  92   t->tm_mon  = ((int)(dostime >> 21) & 0x0f) - 1;
  93   t->tm_year = ((int)(dostime >> 25) & 0x7f) + 80;
  94
  95   return mktime(t);
  96 }
  97
  98 unsigned long dostime(y, n, d, h, m, s)
  99 int y;                  /* year */
 100 int n;                  /* month */
 101 int d;                  /* day */
 102 int h;                  /* hour */
 103 int m;                  /* minute */
 104 int s;                  /* second */
 105 /* Convert the date y/n/d and time h:m:s to a four byte DOS date and
 106    time (date in high two bytes, time in low two bytes allowing magnitude
 107    comparison). */
 108 {
 109   return y < 1980 ? dostime(1980, 1, 1, 0, 0, 0) :
 110     (((unsigned long)y - 1980) << 25) | ((unsigned long)n << 21) |
 111     ((unsigned long)d << 16) | ((unsigned long)h << 11) |
 112     ((unsigned long)m << 5) | ((unsigned long)s >> 1);
 113 }
 114
 115
 116 unsigned long unix2dostime(t)
 117 time_t *t;             /* unix time to convert */
 118 /* Return the Unix time t in DOS format, rounded up to the next two
 119    second boundary. */
 120 {
 121   time_t t_even;
 122   struct tm *s;         /* result of localtime() */
 123
 124   t_even = (*t + 1) & (~1);     /* Round up to even seconds. */
 125   s = localtime(&t_even);       /* Use local time since MSDOS does. */
 126   return dostime(s->tm_year + 1900, s->tm_mon + 1, s->tm_mday,
 127                  s->tm_hour, s->tm_min, s->tm_sec);
 128 }
 129