date/date.c

   1 /*      $NetBSD: date.c,v 1.25 1998/07/28 11:41:47 mycroft Exp $        */
   2
   3 /*
   4  * Copyright (c) 1985, 1987, 1988, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by the University of
  18  *      California, Berkeley and its contributors.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include <sys/cdefs.h>
  37 #ifndef lint
  38 __COPYRIGHT(
  39 "@(#) Copyright (c) 1985, 1987, 1988, 1993\n\
  40         The Regents of the University of California.  All rights reserved.\n");
  41 #endif /* not lint */
  42
  43 #ifndef lint
  44 #if 0
  45 static char sccsid[] = "@(#)date.c      8.2 (Berkeley) 4/28/95";
  46 #else
  47 __RCSID("$NetBSD: date.c,v 1.25 1998/07/28 11:41:47 mycroft Exp $");
  48 #endif
  49 #endif /* not lint */
  50
  51 #include <sys/param.h>
  52 #include <sys/time.h>
  53
  54 #include <ctype.h>
  55 #include <err.h>
  56 #include <fcntl.h>
  57 #include <stdio.h>
  58 #include <stdlib.h>
  59 #include <string.h>
  60 #include <locale.h>
  61 #include <syslog.h>
  62 #include <time.h>
  63 #include <tzfile.h>
  64 #include <unistd.h>
  65 #include <util.h>
  66
  67 #include "extern.h"
  68
  69 time_t tval;
  70 int retval, nflag;
  71
  72 int main __P((int, char *[]));
  73 static void setthetime __P((const char *));
  74 static void badformat __P((void));
  75 static void badtime __P((void));
  76 static void usage __P((void));
  77
  78 int
  79 main(argc, argv)
  80         int argc;
  81         char *argv[];
  82 {
  83         extern int optind;
  84         extern char *optarg;
  85         int ch, rflag;
  86         char *format, buf[1024];
  87
  88         (void)setlocale(LC_ALL, "");
  89
  90         rflag = 0;
  91         while ((ch = getopt(argc, argv, "nr:u")) != -1)
  92                 switch((char)ch) {
  93                 case 'n':               /* don't set network */
  94                         nflag = 1;
  95                         break;
  96                 case 'r':               /* user specified seconds */
  97                         rflag = 1;
  98                         tval = atol(optarg);
  99                         break;
 100                 case 'u':               /* do everything in GMT */
 101                         (void)setenv("TZ", "GMT0", 1);
 102                         break;
 103                 default:
 104                         usage();
 105                 }
 106         argc -= optind;
 107         argv += optind;
 108
 109         if (!rflag && time(&tval) == -1)
 110                 err(1, "time");
 111
 112         format = "%a %b %e %H:%M:%S %Z %Y";
 113
 114         /* allow the operands in any order */
 115         if (*argv && **argv == '+') {
 116                 format = *argv + 1;
 117                 ++argv;
 118         }
 119
 120         if (*argv) {
 121                 setthetime(*argv);
 122                 ++argv;
 123         }
 124
 125         if (*argv && **argv == '+')
 126                 format = *argv + 1;
 127
 128         (void)strftime(buf, sizeof(buf), format, localtime(&tval));
 129         (void)printf("%s\n", buf);
 130         exit(retval);
 131         /* NOTREACHED */
 132 }
 133
 134 #define ATOI2(s)        ((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0'))
 135
 136 void
 137 setthetime(p)
 138         const char *p;
 139 {
 140         struct tm *lt;
 141         struct timeval tv;
 142         const char *dot, *t;
 143         int yearset, len;
 144
 145         for (t = p, dot = NULL; *t; ++t) {
 146                 if (isdigit(*t))
 147                         continue;
 148                 if (*t == '.' && dot == NULL) {
 149                         dot = t;
 150                         continue;
 151                 }
 152                 badformat();
 153         }
 154
 155         lt = localtime(&tval);
 156
 157         if (dot != NULL) {                      /* .ss */
 158                 len = strlen(dot);
 159                 if (len != 3)
 160                         badformat();
 161                 ++dot;
 162                 lt->tm_sec = ATOI2(dot);
 163         } else {
 164                 len = 0;
 165                 lt->tm_sec = 0;
 166         }
 167
 168         yearset = 0;
 169         switch (strlen(p) - len) {
 170         case 12:                                /* cc */
 171                 lt->tm_year = ATOI2(p) * 100 - TM_YEAR_BASE;
 172                 yearset = 1;
 173                 /* FALLTHROUGH */
 174         case 10:                                /* yy */
 175                 if (yearset) {
 176                         lt->tm_year += ATOI2(p);
 177                 } else {
 178                         yearset = ATOI2(p);
 179                         if (yearset < 69)
 180                                 lt->tm_year = yearset + 2000 - TM_YEAR_BASE;
 181                         else
 182                                 lt->tm_year = yearset + 1900 - TM_YEAR_BASE;
 183                 }
 184                 /* FALLTHROUGH */
 185         case 8:                                 /* mm */
 186                 lt->tm_mon = ATOI2(p);
 187                 --lt->tm_mon;                   /* time struct is 0 - 11 */
 188                 /* FALLTHROUGH */
 189         case 6:                                 /* dd */
 190                 lt->tm_mday = ATOI2(p);
 191                 /* FALLTHROUGH */
 192         case 4:                                 /* hh */
 193                 lt->tm_hour = ATOI2(p);
 194                 /* FALLTHROUGH */
 195         case 2:                                 /* mm */
 196                 lt->tm_min = ATOI2(p);
 197                 break;
 198         default:
 199                 badformat();
 200         }
 201
 202         /* convert broken-down time to GMT clock time */
 203         if ((tval = mktime(lt)) == -1)
 204                 badtime();
 205
 206         /* set the time */
 207         if (nflag || netsettime(tval)) {
 208                 logwtmp("|", "date", "");
 209                 tv.tv_sec = tval;
 210                 tv.tv_usec = 0;
 211                 if (settimeofday(&tv, NULL)) {
 212                         perror("date: settimeofday");
 213                         exit(1);
 214                 }
 215                 logwtmp("{", "date", "");
 216         }
 217
 218         if ((p = getlogin()) == NULL)
 219                 p = "???";
 220         syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
 221 }
 222
 223 static void
 224 badformat()
 225 {
 226         warnx("illegal time format");
 227         usage();
 228 }
 229
 230 static void
 231 badtime()
 232 {
 233         errx(1, "illegal time");
 234 }
 235
 236 static void
 237 usage()
 238 {
 239         (void)fprintf(stderr,
 240             "usage: date [-nu] [-r seconds] [+format]\n");
 241         (void)fprintf(stderr, "       date [[[[[cc]yy]mm]dd]hh]mm[.ss]\n");
 242         exit(1);
 243         /* NOTREACHED */
 244 }