1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
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. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #ifndef lint
33 static char const copyright[] =
34 "@(#) Copyright (c) 1985, 1987, 1988, 1993\n\
35 The Regents of the University of California. All rights reserved.\n";
36 #endif /* not lint */
37
38 #if 0
39 #ifndef lint
40 static char sccsid[] = "@(#)date.c 8.2 (Berkeley) 4/28/95";
41 #endif /* not lint */
42 #endif
43
44 #include <sys/cdefs.h>
45 #include <sys/param.h>
46 #include <sys/time.h>
47 #include <sys/stat.h>
48
49 #include <ctype.h>
50 #include <err.h>
51 #include <errno.h>
52 #include <locale.h>
53 #include <stdbool.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <syslog.h>
58 #include <unistd.h>
59 #include <utmpx.h>
60
61 #include "vary.h"
62
63 #ifndef TM_YEAR_BASE
64 #define TM_YEAR_BASE 1900
65 #endif
66
67 static void badformat(void);
68 static void iso8601_usage(const char *) __dead2;
69 static void multipleformats(void);
70 static void printdate(const char *);
71 static void printisodate(struct tm *, long);
72 static void setthetime(const char *, const char *, int, struct timespec *);
73 static size_t strftime_ns(char * __restrict, size_t, const char * __restrict,
74 const struct tm * __restrict, long);
75 static void usage(void) __dead2;
76
77 static const struct iso8601_fmt {
78 const char *refname;
79 const char *format_string;
80 } iso8601_fmts[] = {
81 { "date", "%Y-%m-%d" },
82 { "hours", "T%H" },
83 { "minutes", ":%M" },
84 { "seconds", ":%S" },
85 { "ns", ",%N" },
86 };
87 static const struct iso8601_fmt *iso8601_selected;
88
89 static const char *rfc2822_format = "%a, %d %b %Y %T %z";
90
91 int
main(int argc,char * argv[])92 main(int argc, char *argv[])
93 {
94 struct timespec ts;
95 int ch, rflag;
96 bool Iflag, jflag, Rflag;
97 const char *format;
98 char buf[1024];
99 char *fmt, *outzone = NULL;
100 char *tmp;
101 struct vary *v;
102 const struct vary *badv;
103 struct tm *lt;
104 struct stat sb;
105 size_t i;
106
107 v = NULL;
108 fmt = NULL;
109 (void) setlocale(LC_TIME, "");
110 rflag = 0;
111 Iflag = jflag = Rflag = 0;
112 ts.tv_sec = 0;
113 ts.tv_nsec = 0;
114 while ((ch = getopt(argc, argv, "f:I::jnRr:uv:z:")) != -1)
115 switch((char)ch) {
116 case 'f':
117 fmt = optarg;
118 break;
119 case 'I':
120 if (Rflag)
121 multipleformats();
122 Iflag = 1;
123 if (optarg == NULL) {
124 iso8601_selected = iso8601_fmts;
125 break;
126 }
127 for (i = 0; i < nitems(iso8601_fmts); i++)
128 if (strcmp(optarg, iso8601_fmts[i].refname) == 0)
129 break;
130 if (i == nitems(iso8601_fmts))
131 iso8601_usage(optarg);
132
133 iso8601_selected = &iso8601_fmts[i];
134 break;
135 case 'j':
136 jflag = 1; /* don't set time */
137 break;
138 case 'n':
139 break;
140 case 'R': /* RFC 2822 datetime format */
141 if (Iflag)
142 multipleformats();
143 Rflag = 1;
144 break;
145 case 'r': /* user specified seconds */
146 rflag = 1;
147 ts.tv_sec = strtoq(optarg, &tmp, 0);
148 if (*tmp != 0) {
149 if (stat(optarg, &sb) == 0) {
150 ts.tv_sec = sb.st_mtim.tv_sec;
151 ts.tv_nsec = sb.st_mtim.tv_nsec;
152 } else
153 usage();
154 }
155 break;
156 case 'u': /* do everything in UTC */
157 (void)setenv("TZ", "UTC0", 1);
158 break;
159 case 'z':
160 outzone = optarg;
161 break;
162 case 'v':
163 v = vary_append(v, optarg);
164 break;
165 default:
166 usage();
167 }
168 argc -= optind;
169 argv += optind;
170
171 if (!rflag && clock_gettime(CLOCK_REALTIME, &ts) == -1)
172 err(1, "clock_gettime");
173
174 format = "%+";
175
176 if (Rflag)
177 format = rfc2822_format;
178
179 /* allow the operands in any order */
180 if (*argv && **argv == '+') {
181 if (Iflag)
182 multipleformats();
183 format = *argv + 1;
184 ++argv;
185 }
186
187 if (*argv) {
188 setthetime(fmt, *argv, jflag, &ts);
189 ++argv;
190 } else if (fmt != NULL)
191 usage();
192
193 if (*argv && **argv == '+') {
194 if (Iflag)
195 multipleformats();
196 format = *argv + 1;
197 }
198
199 if (outzone != NULL && setenv("TZ", outzone, 1) != 0)
200 err(1, "setenv(TZ)");
201 lt = localtime(&ts.tv_sec);
202 if (lt == NULL)
203 errx(1, "invalid time");
204 badv = vary_apply(v, lt);
205 if (badv) {
206 fprintf(stderr, "%s: Cannot apply date adjustment\n",
207 badv->arg);
208 vary_destroy(v);
209 usage();
210 }
211 vary_destroy(v);
212
213 if (Iflag)
214 printisodate(lt, ts.tv_nsec);
215
216 if (format == rfc2822_format)
217 /*
218 * When using RFC 2822 datetime format, don't honor the
219 * locale.
220 */
221 setlocale(LC_TIME, "C");
222
223
224 (void)strftime_ns(buf, sizeof(buf), format, lt, ts.tv_nsec);
225 printdate(buf);
226 }
227
228 static void
printdate(const char * buf)229 printdate(const char *buf)
230 {
231 (void)printf("%s\n", buf);
232 if (fflush(stdout))
233 err(1, "stdout");
234 exit(EXIT_SUCCESS);
235 }
236
237 static void
printisodate(struct tm * lt,long nsec)238 printisodate(struct tm *lt, long nsec)
239 {
240 const struct iso8601_fmt *it;
241 char fmtbuf[64], buf[64], tzbuf[8];
242
243 fmtbuf[0] = 0;
244 for (it = iso8601_fmts; it <= iso8601_selected; it++)
245 strlcat(fmtbuf, it->format_string, sizeof(fmtbuf));
246
247 (void)strftime_ns(buf, sizeof(buf), fmtbuf, lt, nsec);
248
249 if (iso8601_selected > iso8601_fmts) {
250 (void)strftime_ns(tzbuf, sizeof(tzbuf), "%z", lt, nsec);
251 memmove(&tzbuf[4], &tzbuf[3], 3);
252 tzbuf[3] = ':';
253 strlcat(buf, tzbuf, sizeof(buf));
254 }
255
256 printdate(buf);
257 }
258
259 #define ATOI2(s) ((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0'))
260
261 static void
setthetime(const char * fmt,const char * p,int jflag,struct timespec * ts)262 setthetime(const char *fmt, const char *p, int jflag, struct timespec *ts)
263 {
264 struct utmpx utx;
265 struct tm *lt;
266 const char *dot, *t;
267 int century;
268
269 lt = localtime(&ts->tv_sec);
270 if (lt == NULL)
271 errx(1, "invalid time");
272 lt->tm_isdst = -1; /* divine correct DST */
273
274 if (fmt != NULL) {
275 t = strptime(p, fmt, lt);
276 if (t == NULL) {
277 fprintf(stderr, "Failed conversion of ``%s''"
278 " using format ``%s''\n", p, fmt);
279 badformat();
280 } else if (*t != '\0')
281 fprintf(stderr, "Warning: Ignoring %ld extraneous"
282 " characters in date string (%s)\n",
283 (long) strlen(t), t);
284 } else {
285 for (t = p, dot = NULL; *t; ++t) {
286 if (isdigit(*t))
287 continue;
288 if (*t == '.' && dot == NULL) {
289 dot = t;
290 continue;
291 }
292 badformat();
293 }
294
295 if (dot != NULL) { /* .ss */
296 dot++; /* *dot++ = '\0'; */
297 if (strlen(dot) != 2)
298 badformat();
299 lt->tm_sec = ATOI2(dot);
300 if (lt->tm_sec > 61)
301 badformat();
302 } else
303 lt->tm_sec = 0;
304
305 century = 0;
306 /* if p has a ".ss" field then let's pretend it's not there */
307 switch (strlen(p) - ((dot != NULL) ? 3 : 0)) {
308 case 12: /* cc */
309 lt->tm_year = ATOI2(p) * 100 - TM_YEAR_BASE;
310 century = 1;
311 /* FALLTHROUGH */
312 case 10: /* yy */
313 if (century)
314 lt->tm_year += ATOI2(p);
315 else {
316 lt->tm_year = ATOI2(p);
317 if (lt->tm_year < 69) /* hack for 2000 ;-} */
318 lt->tm_year += 2000 - TM_YEAR_BASE;
319 else
320 lt->tm_year += 1900 - TM_YEAR_BASE;
321 }
322 /* FALLTHROUGH */
323 case 8: /* mm */
324 lt->tm_mon = ATOI2(p);
325 if (lt->tm_mon > 12)
326 badformat();
327 --lt->tm_mon; /* time struct is 0 - 11 */
328 /* FALLTHROUGH */
329 case 6: /* dd */
330 lt->tm_mday = ATOI2(p);
331 if (lt->tm_mday > 31)
332 badformat();
333 /* FALLTHROUGH */
334 case 4: /* HH */
335 lt->tm_hour = ATOI2(p);
336 if (lt->tm_hour > 23)
337 badformat();
338 /* FALLTHROUGH */
339 case 2: /* MM */
340 lt->tm_min = ATOI2(p);
341 if (lt->tm_min > 59)
342 badformat();
343 break;
344 default:
345 badformat();
346 }
347 }
348
349 /* convert broken-down time to GMT clock time */
350 lt->tm_yday = -1;
351 ts->tv_sec = mktime(lt);
352 if (lt->tm_yday == -1)
353 errx(1, "nonexistent time");
354 ts->tv_nsec = 0;
355
356 if (!jflag) {
357 utx.ut_type = OLD_TIME;
358 memset(utx.ut_id, 0, sizeof(utx.ut_id));
359 (void)gettimeofday(&utx.ut_tv, NULL);
360 pututxline(&utx);
361 if (clock_settime(CLOCK_REALTIME, ts) != 0)
362 err(1, "clock_settime");
363 utx.ut_type = NEW_TIME;
364 (void)gettimeofday(&utx.ut_tv, NULL);
365 pututxline(&utx);
366
367 if ((p = getlogin()) == NULL)
368 p = "???";
369 syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
370 }
371 }
372
373 /*
374 * The strftime_ns function is a wrapper around strftime(3), which adds support
375 * for features absent from strftime(3). Currently, the only extra feature is
376 * support for %N, the nanosecond conversion specification.
377 *
378 * The functions scans the format string for the non-standard conversion
379 * specifications and replaces them with the date and time values before
380 * passing the format string to strftime(3). The handling of the non-standard
381 * conversion specifications happens before the call to strftime(3) to handle
382 * cases like "%%N" correctly ("%%N" should yield "%N" instead of nanoseconds).
383 */
384 static size_t
strftime_ns(char * __restrict s,size_t maxsize,const char * __restrict format,const struct tm * __restrict t,long nsec)385 strftime_ns(char * __restrict s, size_t maxsize, const char * __restrict format,
386 const struct tm * __restrict t, long nsec)
387 {
388 size_t prefixlen;
389 size_t ret;
390 char *newformat;
391 char *oldformat;
392 const char *prefix;
393 const char *suffix;
394 const char *tok;
395 bool seen_percent;
396
397 seen_percent = false;
398 if ((newformat = strdup(format)) == NULL)
399 err(1, "strdup");
400 tok = newformat;
401 for (tok = newformat; *tok != '\0'; tok++) {
402 switch (*tok) {
403 case '%':
404 /*
405 * If the previous token was a percent sign,
406 * then there are two percent tokens in a row.
407 */
408 if (seen_percent)
409 seen_percent = false;
410 else
411 seen_percent = true;
412 break;
413 case 'N':
414 if (seen_percent) {
415 oldformat = newformat;
416 prefix = oldformat;
417 prefixlen = tok - oldformat - 1;
418 suffix = tok + 1;
419 /*
420 * Construct a new format string from the
421 * prefix (i.e., the part of the old format
422 * from its beginning to the currently handled
423 * "%N" conversion specification), the
424 * nanoseconds, and the suffix (i.e., the part
425 * of the old format from the next token to the
426 * end).
427 */
428 if (asprintf(&newformat, "%.*s%.9ld%s",
429 (int)prefixlen, prefix, nsec,
430 suffix) < 0) {
431 err(1, "asprintf");
432 }
433 free(oldformat);
434 tok = newformat + prefixlen + 9;
435 }
436 seen_percent = false;
437 break;
438 default:
439 seen_percent = false;
440 break;
441 }
442 }
443
444 ret = strftime(s, maxsize, newformat, t);
445 free(newformat);
446 return (ret);
447 }
448
449 static void
badformat(void)450 badformat(void)
451 {
452 warnx("illegal time format");
453 usage();
454 }
455
456 static void
iso8601_usage(const char * badarg)457 iso8601_usage(const char *badarg)
458 {
459 errx(1, "invalid argument '%s' for -I", badarg);
460 }
461
462 static void
multipleformats(void)463 multipleformats(void)
464 {
465 errx(1, "multiple output formats specified");
466 }
467
468 static void
usage(void)469 usage(void)
470 {
471 (void)fprintf(stderr, "%s\n%s\n%s\n",
472 "usage: date [-jnRu] [-I[date|hours|minutes|seconds|ns]] [-f input_fmt]",
473 " "
474 "[ -z output_zone ] [-r filename|seconds] [-v[+|-]val[y|m|w|d|H|M|S]]",
475 " "
476 "[[[[[[cc]yy]mm]dd]HH]MM[.SS] | new_date] [+output_fmt]"
477 );
478 exit(1);
479 }
480