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 #include <sys/param.h>
33 #include <sys/time.h>
34 #include <sys/stat.h>
35
36 #include <ctype.h>
37 #include <err.h>
38 #include <errno.h>
39 #include <inttypes.h>
40 #include <locale.h>
41 #include <stdbool.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <syslog.h>
46 #include <unistd.h>
47 #include <utmpx.h>
48
49 #include "vary.h"
50
51 #ifndef TM_YEAR_BASE
52 #define TM_YEAR_BASE 1900
53 #endif
54
55 static void badformat(void);
56 static void iso8601_usage(const char *) __dead2;
57 static void multipleformats(void);
58 static void printdate(const char *);
59 static void printisodate(struct tm *, long, long);
60 static void setthetime(const char *, const char *, int, struct timespec *);
61 static size_t strftime_ns(char * __restrict, size_t, const char * __restrict,
62 const struct tm * __restrict, long, long);
63 static void usage(void) __dead2;
64
65 static const struct iso8601_fmt {
66 const char *refname;
67 const char *format_string;
68 } iso8601_fmts[] = {
69 { "date", "%Y-%m-%d" },
70 { "hours", "T%H" },
71 { "minutes", ":%M" },
72 { "seconds", ":%S" },
73 { "ns", ",%N" },
74 };
75 static const struct iso8601_fmt *iso8601_selected;
76
77 static const char *rfc2822_format = "%a, %d %b %Y %T %z";
78
79 int
main(int argc,char * argv[])80 main(int argc, char *argv[])
81 {
82 struct timespec ts = { 0, 0 }, tres = { 0, 1 };
83 int ch, rflag;
84 bool Iflag, jflag, Rflag;
85 const char *format;
86 char buf[1024];
87 char *end, *fmt, *outzone = NULL;
88 struct vary *v;
89 const struct vary *badv;
90 struct tm *lt;
91 struct stat sb;
92 size_t i;
93 intmax_t number;
94
95 v = NULL;
96 fmt = NULL;
97 (void) setlocale(LC_TIME, "");
98 rflag = 0;
99 Iflag = jflag = Rflag = 0;
100 while ((ch = getopt(argc, argv, "f:I::jnRr:uv:z:")) != -1)
101 switch((char)ch) {
102 case 'f':
103 fmt = optarg;
104 break;
105 case 'I':
106 if (Rflag)
107 multipleformats();
108 Iflag = 1;
109 if (optarg == NULL) {
110 iso8601_selected = iso8601_fmts;
111 break;
112 }
113 for (i = 0; i < nitems(iso8601_fmts); i++)
114 if (strcmp(optarg, iso8601_fmts[i].refname) == 0)
115 break;
116 if (i == nitems(iso8601_fmts))
117 iso8601_usage(optarg);
118
119 iso8601_selected = &iso8601_fmts[i];
120 break;
121 case 'j':
122 jflag = 1; /* don't set time */
123 break;
124 case 'n':
125 break;
126 case 'R': /* RFC 2822 datetime format */
127 if (Iflag)
128 multipleformats();
129 Rflag = 1;
130 break;
131 case 'r': /* user specified seconds */
132 rflag = 1;
133 number = strtoimax(optarg, &end, 0);
134 if (end > optarg && *end == '\0') {
135 ts.tv_sec = number;
136 ts.tv_nsec = 0;
137 } else if (stat(optarg, &sb) == 0) {
138 ts.tv_sec = sb.st_mtim.tv_sec;
139 ts.tv_nsec = sb.st_mtim.tv_nsec;
140 } else {
141 usage();
142 }
143 break;
144 case 'u': /* do everything in UTC */
145 (void)setenv("TZ", "UTC0", 1);
146 break;
147 case 'z':
148 outzone = optarg;
149 break;
150 case 'v':
151 v = vary_append(v, optarg);
152 break;
153 default:
154 usage();
155 }
156 argc -= optind;
157 argv += optind;
158
159 if (!rflag) {
160 if (clock_gettime(CLOCK_REALTIME, &ts) == -1)
161 err(1, "clock_gettime");
162 if (clock_getres(CLOCK_REALTIME, &tres) == -1)
163 err(1, "clock_getres");
164 }
165
166 format = "%+";
167
168 if (Rflag)
169 format = rfc2822_format;
170
171 /* allow the operands in any order */
172 if (*argv && **argv == '+') {
173 if (Iflag)
174 multipleformats();
175 format = *argv + 1;
176 ++argv;
177 }
178
179 if (*argv) {
180 setthetime(fmt, *argv, jflag, &ts);
181 ++argv;
182 } else if (fmt != NULL)
183 usage();
184
185 if (*argv && **argv == '+') {
186 if (Iflag)
187 multipleformats();
188 format = *argv + 1;
189 }
190
191 if (outzone != NULL && setenv("TZ", outzone, 1) != 0)
192 err(1, "setenv(TZ)");
193 lt = localtime(&ts.tv_sec);
194 if (lt == NULL)
195 errx(1, "invalid time");
196 badv = vary_apply(v, lt);
197 if (badv) {
198 fprintf(stderr, "%s: Cannot apply date adjustment\n",
199 badv->arg);
200 vary_destroy(v);
201 usage();
202 }
203 vary_destroy(v);
204
205 if (Iflag)
206 printisodate(lt, ts.tv_nsec, tres.tv_nsec);
207
208 if (format == rfc2822_format)
209 /*
210 * When using RFC 2822 datetime format, don't honor the
211 * locale.
212 */
213 setlocale(LC_TIME, "C");
214
215
216 (void)strftime_ns(buf, sizeof(buf), format, lt,
217 ts.tv_nsec, tres.tv_nsec);
218 printdate(buf);
219 }
220
221 static void
printdate(const char * buf)222 printdate(const char *buf)
223 {
224 (void)printf("%s\n", buf);
225 if (fflush(stdout))
226 err(1, "stdout");
227 exit(EXIT_SUCCESS);
228 }
229
230 static void
printisodate(struct tm * lt,long nsec,long res)231 printisodate(struct tm *lt, long nsec, long res)
232 {
233 const struct iso8601_fmt *it;
234 char fmtbuf[64], buf[64], tzbuf[8];
235
236 fmtbuf[0] = 0;
237 for (it = iso8601_fmts; it <= iso8601_selected; it++)
238 strlcat(fmtbuf, it->format_string, sizeof(fmtbuf));
239
240 (void)strftime_ns(buf, sizeof(buf), fmtbuf, lt, nsec, res);
241
242 if (iso8601_selected > iso8601_fmts) {
243 (void)strftime_ns(tzbuf, sizeof(tzbuf), "%z", lt, nsec, res);
244 memmove(&tzbuf[4], &tzbuf[3], 3);
245 tzbuf[3] = ':';
246 strlcat(buf, tzbuf, sizeof(buf));
247 }
248
249 printdate(buf);
250 }
251
252 #define ATOI2(s) ((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0'))
253
254 static void
setthetime(const char * fmt,const char * p,int jflag,struct timespec * ts)255 setthetime(const char *fmt, const char *p, int jflag, struct timespec *ts)
256 {
257 struct utmpx utx;
258 struct tm *lt;
259 const char *dot, *t;
260 int century;
261
262 lt = localtime(&ts->tv_sec);
263 if (lt == NULL)
264 errx(1, "invalid time");
265 lt->tm_isdst = -1; /* divine correct DST */
266
267 if (fmt != NULL) {
268 t = strptime(p, fmt, lt);
269 if (t == NULL) {
270 fprintf(stderr, "Failed conversion of ``%s''"
271 " using format ``%s''\n", p, fmt);
272 badformat();
273 } else if (*t != '\0')
274 fprintf(stderr, "Warning: Ignoring %ld extraneous"
275 " characters in date string (%s)\n",
276 (long) strlen(t), t);
277 } else {
278 for (t = p, dot = NULL; *t; ++t) {
279 if (isdigit(*t))
280 continue;
281 if (*t == '.' && dot == NULL) {
282 dot = t;
283 continue;
284 }
285 badformat();
286 }
287
288 if (dot != NULL) { /* .ss */
289 dot++; /* *dot++ = '\0'; */
290 if (strlen(dot) != 2)
291 badformat();
292 lt->tm_sec = ATOI2(dot);
293 if (lt->tm_sec > 61)
294 badformat();
295 } else
296 lt->tm_sec = 0;
297
298 century = 0;
299 /* if p has a ".ss" field then let's pretend it's not there */
300 switch (strlen(p) - ((dot != NULL) ? 3 : 0)) {
301 case 12: /* cc */
302 lt->tm_year = ATOI2(p) * 100 - TM_YEAR_BASE;
303 century = 1;
304 /* FALLTHROUGH */
305 case 10: /* yy */
306 if (century)
307 lt->tm_year += ATOI2(p);
308 else {
309 lt->tm_year = ATOI2(p);
310 if (lt->tm_year < 69) /* hack for 2000 ;-} */
311 lt->tm_year += 2000 - TM_YEAR_BASE;
312 else
313 lt->tm_year += 1900 - TM_YEAR_BASE;
314 }
315 /* FALLTHROUGH */
316 case 8: /* mm */
317 lt->tm_mon = ATOI2(p);
318 if (lt->tm_mon > 12)
319 badformat();
320 --lt->tm_mon; /* time struct is 0 - 11 */
321 /* FALLTHROUGH */
322 case 6: /* dd */
323 lt->tm_mday = ATOI2(p);
324 if (lt->tm_mday > 31)
325 badformat();
326 /* FALLTHROUGH */
327 case 4: /* HH */
328 lt->tm_hour = ATOI2(p);
329 if (lt->tm_hour > 23)
330 badformat();
331 /* FALLTHROUGH */
332 case 2: /* MM */
333 lt->tm_min = ATOI2(p);
334 if (lt->tm_min > 59)
335 badformat();
336 break;
337 default:
338 badformat();
339 }
340 }
341
342 /* convert broken-down time to GMT clock time */
343 lt->tm_yday = -1;
344 ts->tv_sec = mktime(lt);
345 if (lt->tm_yday == -1)
346 errx(1, "nonexistent time");
347 ts->tv_nsec = 0;
348
349 if (!jflag) {
350 utx.ut_type = OLD_TIME;
351 memset(utx.ut_id, 0, sizeof(utx.ut_id));
352 (void)gettimeofday(&utx.ut_tv, NULL);
353 pututxline(&utx);
354 if (clock_settime(CLOCK_REALTIME, ts) != 0)
355 err(1, "clock_settime");
356 utx.ut_type = NEW_TIME;
357 (void)gettimeofday(&utx.ut_tv, NULL);
358 pututxline(&utx);
359
360 if ((p = getlogin()) == NULL)
361 p = "???";
362 syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
363 }
364 }
365
366 /*
367 * The strftime_ns function is a wrapper around strftime(3), which adds support
368 * for features absent from strftime(3). Currently, the only extra feature is
369 * support for %N, the nanosecond conversion specification.
370 *
371 * The functions scans the format string for the non-standard conversion
372 * specifications and replaces them with the date and time values before
373 * passing the format string to strftime(3). The handling of the non-standard
374 * conversion specifications happens before the call to strftime(3) to handle
375 * cases like "%%N" correctly ("%%N" should yield "%N" instead of nanoseconds).
376 */
377 static size_t
strftime_ns(char * __restrict s,size_t maxsize,const char * __restrict format,const struct tm * __restrict t,long nsec,long res)378 strftime_ns(char * __restrict s, size_t maxsize, const char * __restrict format,
379 const struct tm * __restrict t, long nsec, long res)
380 {
381 size_t ret;
382 char *newformat;
383 char *oldformat;
384 const char *prefix;
385 const char *suffix;
386 const char *tok;
387 long number;
388 int i, len, prefixlen, width, zeroes;
389 bool seen_percent, seen_dash, seen_width;
390
391 seen_percent = false;
392 if ((newformat = strdup(format)) == NULL)
393 err(1, "strdup");
394 tok = newformat;
395 for (tok = newformat; *tok != '\0'; tok++) {
396 switch (*tok) {
397 case '%':
398 /*
399 * If the previous token was a percent sign,
400 * then there are two percent tokens in a row.
401 */
402 if (seen_percent) {
403 seen_percent = false;
404 } else {
405 seen_percent = true;
406 seen_dash = seen_width = false;
407 prefixlen = tok - newformat;
408 width = 0;
409 }
410 break;
411 case 'N':
412 if (!seen_percent)
413 break;
414 oldformat = newformat;
415 prefix = oldformat;
416 suffix = tok + 1;
417 /*
418 * Prepare the number we are about to print. If
419 * the requested width is less than 9, we need to
420 * cut off the least significant digits. If it is
421 * more than 9, we will have to append zeroes.
422 */
423 if (seen_dash) {
424 /*
425 * Calculate number of singificant digits
426 * based on res which is the clock's
427 * resolution in nanoseconds.
428 */
429 for (width = 9, number = res;
430 width > 0 && number > 0;
431 width--, number /= 10)
432 /* nothing */;
433 }
434 number = nsec;
435 zeroes = 0;
436 if (width == 0) {
437 width = 9;
438 } else if (width > 9) {
439 zeroes = width - 9;
440 width = 9;
441 } else {
442 for (i = 0; i < 9 - width; i++)
443 number /= 10;
444 }
445 /*
446 * Construct a new format string from the prefix
447 * (i.e., the part of the old format from its
448 * beginning to the currently handled "%N"
449 * conversion specification), the nanoseconds, and
450 * the suffix (i.e., the part of the old format
451 * from the next token to the end).
452 */
453 asprintf(&newformat, "%.*s%.*ld%.*d%n%s", prefixlen,
454 prefix, width, number, zeroes, 0, &len, suffix);
455 if (newformat == NULL)
456 err(1, "asprintf");
457 free(oldformat);
458 tok = newformat + len - 1;
459 seen_percent = false;
460 break;
461 case '-':
462 if (seen_percent) {
463 if (seen_dash || seen_width) {
464 seen_percent = false;
465 break;
466 }
467 seen_dash = true;
468 }
469 break;
470 case '0': case '1': case '2': case '3': case '4':
471 case '5': case '6': case '7': case '8': case '9':
472 if (seen_percent) {
473 if (seen_dash) {
474 seen_percent = false;
475 break;
476 }
477 width = width * 10 + *tok - '0';
478 seen_width = true;
479 }
480 break;
481 default:
482 seen_percent = false;
483 break;
484 }
485 }
486
487 ret = strftime(s, maxsize, newformat, t);
488 free(newformat);
489 return (ret);
490 }
491
492 static void
badformat(void)493 badformat(void)
494 {
495 warnx("illegal time format");
496 usage();
497 }
498
499 static void
iso8601_usage(const char * badarg)500 iso8601_usage(const char *badarg)
501 {
502 errx(1, "invalid argument '%s' for -I", badarg);
503 }
504
505 static void
multipleformats(void)506 multipleformats(void)
507 {
508 errx(1, "multiple output formats specified");
509 }
510
511 static void
usage(void)512 usage(void)
513 {
514 (void)fprintf(stderr, "%s\n%s\n%s\n",
515 "usage: date [-jnRu] [-I[date|hours|minutes|seconds|ns]] [-f input_fmt]",
516 " "
517 "[ -z output_zone ] [-r filename|seconds] [-v[+|-]val[y|m|w|d|H|M|S]]",
518 " "
519 "[[[[[[cc]yy]mm]dd]HH]MM[.SS] | new_date] [+output_fmt]"
520 );
521 exit(1);
522 }
523