bin/date/date.c

   1 /*
   2  * Copyright (c) 1985, 1987, 1988, 1993
   3  *      The Regents of the University of California.  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  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#) Copyright (c) 1985, 1987, 1988, 1993 The Regents of the University of California.  All rights reserved.
  30  * @(#)date.c   8.2 (Berkeley) 4/28/95
  31  * $FreeBSD: src/bin/date/date.c,v 1.47 2005/01/10 08:39:21 imp Exp $
  32  */
  33
  34 #include <sys/param.h>
  35 #include <sys/time.h>
  36
  37 #include <ctype.h>
  38 #include <err.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <syslog.h>
  43 #include <unistd.h>
  44 #include <locale.h>
  45 #include <libutil.h>
  46 #include <utmpx.h>
  47
  48 #include "vary.h"
  49
  50 #ifndef TM_YEAR_BASE
  51 #define TM_YEAR_BASE    1900
  52 #endif
  53
  54 static time_t tval;
  55
  56 static void setthetime(const char *, const char *, int);
  57 static void badformat(void);
  58 static void usage(void);
  59
  60 static const char *rfc2822_format ="%a, %d %b %Y %T %z";
  61
  62 int
  63 main(int argc, char **argv)
  64 {
  65         int ch, rflag;
  66         int jflag, Rflag;
  67         const char *format;
  68         char buf[1024];
  69         char *fmt;
  70         char *tmp;
  71         struct vary *v;
  72         const struct vary *badv;
  73         struct tm lt;
  74
  75         v = NULL;
  76         fmt = NULL;
  77         setlocale(LC_TIME, "");
  78         rflag = 0;
  79         jflag = Rflag = 0;
  80         while ((ch = getopt(argc, argv, "f:jnRr:uv:")) != -1)
  81                 switch(ch) {
  82                 case 'f':
  83                         fmt = optarg;
  84                         break;
  85                 case 'j':
  86                         jflag = 1;      /* don't set time */
  87                         break;
  88                 case 'n':               /* don't set network */
  89                         break;
  90                 case 'R':
  91                         Rflag = 1;      /*RFC 2822 datetime format */
  92                         break;
  93                 case 'r':               /* user specified seconds */
  94                         rflag = 1;
  95                         tval = strtoll(optarg, &tmp, 0);
  96                         if (*tmp != 0)
  97                                 usage();
  98                         break;
  99                 case 'u':               /* do everything in UTC */
 100                         if (setenv("TZ", "UTC0", 1) != 0)
 101                                 err(1, "setenv: cannot set TZ=UTC0");
 102                         break;
 103                 case 'v':
 104                         v = vary_append(v, optarg);
 105                         break;
 106                 default:
 107                         usage();
 108                 }
 109         argc -= optind;
 110         argv += optind;
 111
 112         if (!rflag && time(&tval) == -1)
 113                 err(1, "time");
 114
 115         format = "%+";
 116
 117         if (Rflag)
 118                 format = rfc2822_format;
 119
 120         /* allow the operands in any order */
 121         if (*argv && **argv == '+') {
 122                 format = *argv + 1;
 123                 ++argv;
 124         }
 125
 126         if (*argv) {
 127                 setthetime(fmt, *argv, jflag);
 128                 ++argv;
 129         } else if (fmt != NULL)
 130                 usage();
 131
 132         if (*argv && **argv == '+')
 133                 format = *argv + 1;
 134
 135         lt = *localtime(&tval);
 136         badv = vary_apply(v, &lt);
 137         if (badv) {
 138                 fprintf(stderr, "%s: Cannot apply date adjustment\n",
 139                         badv->arg);
 140                 vary_destroy(v);
 141                 usage();
 142         }
 143         vary_destroy(v);
 144
 145         if (format == rfc2822_format) {
 146                 /*
 147                  * When using RFC 2822 datetime format, don't honor the
 148                  * locale.
 149                  */
 150                 setlocale(LC_TIME, "C");
 151         }
 152
 153         strftime(buf, sizeof(buf), format, &lt);
 154         printf("%s\n", buf);
 155         if (fflush(stdout) != 0)
 156                 err(1, "stdout");
 157         exit(EXIT_SUCCESS);
 158 }
 159
 160 #define ATOI2(s)        ((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0'))
 161
 162 static void
 163 setthetime(const char *fmt, const char *p, int jflag)
 164 {
 165         struct tm *lt;
 166         struct timeval tv;
 167         const char *dot, *t;
 168         int century;
 169
 170         if (fmt != NULL) {
 171                 lt = localtime(&tval);
 172                 t = strptime(p, fmt, lt);
 173                 if (t == NULL) {
 174                         fprintf(stderr, "Failed conversion of ``%s''"
 175                                 " using format ``%s''\n", p, fmt);
 176                         badformat();
 177                 } else if (*t != '\0')
 178                         fprintf(stderr, "Warning: Ignoring %ld extraneous"
 179                                 " characters in date string (%s)\n",
 180                                 (long) strlen(t), t);
 181         } else {
 182                 for (t = p, dot = NULL; *t; ++t) {
 183                         if (isdigit(*t))
 184                                 continue;
 185                         if (*t == '.' && dot == NULL) {
 186                                 dot = t;
 187                                 continue;
 188                         }
 189                         badformat();
 190                 }
 191
 192                 lt = localtime(&tval);
 193
 194                 if (dot != NULL) {                      /* .ss */
 195                         dot++; /* *dot++ = '\0'; */
 196                         if (strlen(dot) != 2)
 197                                 badformat();
 198                         lt->tm_sec = ATOI2(dot);
 199                         if (lt->tm_sec > 61)
 200                                 badformat();
 201                 } else
 202                         lt->tm_sec = 0;
 203
 204                 century = 0;
 205                 /* if p has a ".ss" field then let's pretend it's not there */
 206                 switch (strlen(p) - ((dot != NULL) ? 3 : 0)) {
 207                 case 12:                                /* cc */
 208                         lt->tm_year = ATOI2(p) * 100 - TM_YEAR_BASE;
 209                         century = 1;
 210                         /* FALLTHROUGH */
 211                 case 10:                                /* yy */
 212                         if (century)
 213                                 lt->tm_year += ATOI2(p);
 214                         else {                          /* hack for 2000 ;-} */
 215                                 lt->tm_year = ATOI2(p);
 216                                 if (lt->tm_year < 69)
 217                                         lt->tm_year += 2000 - TM_YEAR_BASE;
 218                                 else
 219                                         lt->tm_year += 1900 - TM_YEAR_BASE;
 220                         }
 221                         /* FALLTHROUGH */
 222                 case 8:                                 /* mm */
 223                         lt->tm_mon = ATOI2(p);
 224                         if (lt->tm_mon > 12)
 225                                 badformat();
 226                         --lt->tm_mon;           /* time struct is 0 - 11 */
 227                         /* FALLTHROUGH */
 228                 case 6:                                 /* dd */
 229                         lt->tm_mday = ATOI2(p);
 230                         if (lt->tm_mday > 31)
 231                                 badformat();
 232                         /* FALLTHROUGH */
 233                 case 4:                                 /* HH */
 234                         lt->tm_hour = ATOI2(p);
 235                         if (lt->tm_hour > 23)
 236                                 badformat();
 237                         /* FALLTHROUGH */
 238                 case 2:                                 /* MM */
 239                         lt->tm_min = ATOI2(p);
 240                         if (lt->tm_min > 59)
 241                                 badformat();
 242                         break;
 243                 default:
 244                         badformat();
 245                 }
 246         }
 247
 248         /* Let mktime() decide whether summer time is in effect. */
 249         lt->tm_isdst = -1;
 250
 251         /* convert broken-down time to GMT clock time */
 252         if ((tval = mktime(lt)) == -1)
 253                 errx(1, "nonexistent time");
 254
 255         if (!jflag) {
 256                 logwtmpx("|", "date", "", 0, OLD_TIME);
 257                 tv.tv_sec = tval;
 258                 tv.tv_usec = 0;
 259                 if (settimeofday(&tv, NULL))
 260                         err(1, "settimeofday (timeval)");
 261                 logwtmpx("{", "date", "", 0, NEW_TIME);
 262
 263                 if ((p = getlogin()) == NULL)
 264                         p = "???";
 265                 syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
 266         }
 267 }
 268
 269 static void
 270 badformat(void)
 271 {
 272         warnx("illegal time format");
 273         usage();
 274 }
 275
 276 static void
 277 usage(void)
 278 {
 279         fprintf(stderr, "%s\n%s\n",
 280             "usage: date [-jnRu] [-r seconds] [-v[+|-]val[ymwdHMS]] ... ",
 281             "            "
 282             "[-f fmt date | [[[[[cc]yy]mm]dd]HH]MM[.ss]] [+format]");
 283         exit(1);
 284 }