xref: /illumos-gate/usr/src/cmd/zdump/zdump.c (revision bc54f855e0de1e590115101c80f152a20722cfb0)
1 /*
2  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*
7  * Copyright (c) 2018, Joyent, Inc.
8  */
9 
10 /*
11  * zdump 7.24
12  * Taken from elsie.nci.nih.gov to replace the existing Solaris zdump,
13  * which was based on an earlier version of the elsie code.
14  *
15  * For zdump 7.24, the following changes were made to the elsie code:
16  *   locale/textdomain/messages to match existing Solaris style.
17  *   Solaris verbose mode is documented to display the current time first.
18  *   cstyle cleaned code.
19  *   removed old locale/textdomain code.
20  */
21 
22 static char	elsieid[] = "@(#)zdump.c	7.74";
23 
24 /*
25  * This code has been made independent of the rest of the time
26  * conversion package to increase confidence in the verification it provides.
27  * You can use this code to help in verifying other implementations.
28  */
29 
30 #include "stdio.h"	/* for stdout, stderr, perror */
31 #include "string.h"	/* for strcpy */
32 #include "sys/types.h"	/* for time_t */
33 #include "time.h"	/* for struct tm */
34 #include "stdlib.h"	/* for exit, malloc, atoi */
35 #include "locale.h"	/* for setlocale, textdomain */
36 #include "libintl.h"
37 #include <ctype.h>
38 #include "tzfile.h"	/* for defines */
39 #include <limits.h>
40 
41 #ifndef ZDUMP_LO_YEAR
42 #define	ZDUMP_LO_YEAR	(-500)
43 #endif /* !defined ZDUMP_LO_YEAR */
44 
45 #ifndef ZDUMP_HI_YEAR
46 #define	ZDUMP_HI_YEAR	2500
47 #endif /* !defined ZDUMP_HI_YEAR */
48 
49 #ifndef MAX_STRING_LENGTH
50 #define	MAX_STRING_LENGTH	1024
51 #endif /* !defined MAX_STRING_LENGTH */
52 
53 #ifndef TRUE
54 #define	TRUE		1
55 #endif /* !defined TRUE */
56 
57 #ifndef FALSE
58 #define	FALSE		0
59 #endif /* !defined FALSE */
60 
61 #ifndef isleap_sum
62 /*
63  * See tzfile.h for details on isleap_sum.
64  */
65 #define	isleap_sum(a, b)	isleap((a) % 400 + (b) % 400)
66 #endif /* !defined isleap_sum */
67 
68 #ifndef SECSPERDAY
69 #define	SECSPERDAY	((long)SECSPERHOUR * HOURSPERDAY)
70 #endif
71 #define	SECSPERNYEAR	(SECSPERDAY * DAYSPERNYEAR)
72 #define	SECSPERLYEAR	(SECSPERNYEAR + SECSPERDAY)
73 
74 #ifndef GNUC_or_lint
75 #ifdef lint
76 #define	GNUC_or_lint
77 #else /* !defined lint */
78 #ifdef __GNUC__
79 #define	GNUC_or_lint
80 #endif /* defined __GNUC__ */
81 #endif /* !defined lint */
82 #endif /* !defined GNUC_or_lint */
83 
84 #ifndef INITIALIZE
85 #ifdef	GNUC_or_lint
86 #define	INITIALIZE(x)	((x) = 0)
87 #else /* !defined GNUC_or_lint */
88 #define	INITIALIZE(x)
89 #endif /* !defined GNUC_or_lint */
90 #endif /* !defined INITIALIZE */
91 
92 static time_t	absolute_min_time;
93 static time_t	absolute_max_time;
94 static size_t	longest;
95 static char	*progname;
96 static int	warned;
97 
98 static char	*abbr(struct tm *);
99 static void	abbrok(const char *, const char *);
100 static long	delta(struct tm *, struct tm *);
101 static void	dumptime(const struct tm *);
102 static time_t	hunt(char *, time_t, time_t);
103 static void	setabsolutes(void);
104 static void	show(char *, time_t, int);
105 static void	usage(void);
106 static const char	*tformat(void);
107 static time_t	yeartot(long y);
108 
109 #ifndef TYPECHECK
110 #define	my_localtime	localtime
111 #else /* !defined TYPECHECK */
112 static struct tm *
my_localtime(tp)113 my_localtime(tp)
114 time_t *tp;
115 {
116 	register struct tm *tmp;
117 
118 	tmp = localtime(tp);
119 	if (tp != NULL && tmp != NULL) {
120 		struct tm	tm;
121 		register time_t	t;
122 
123 		tm = *tmp;
124 		t = mktime(&tm);
125 		if (t - *tp >= 1 || *tp - t >= 1) {
126 			(void) fflush(stdout);
127 			(void) fprintf(stderr, "\n%s: ", progname);
128 			(void) fprintf(stderr, tformat(), *tp);
129 			(void) fprintf(stderr, " ->");
130 			(void) fprintf(stderr, " year=%d", tmp->tm_year);
131 			(void) fprintf(stderr, " mon=%d", tmp->tm_mon);
132 			(void) fprintf(stderr, " mday=%d", tmp->tm_mday);
133 			(void) fprintf(stderr, " hour=%d", tmp->tm_hour);
134 			(void) fprintf(stderr, " min=%d", tmp->tm_min);
135 			(void) fprintf(stderr, " sec=%d", tmp->tm_sec);
136 			(void) fprintf(stderr, " isdst=%d", tmp->tm_isdst);
137 			(void) fprintf(stderr, " -> ");
138 			(void) fprintf(stderr, tformat(), t);
139 			(void) fprintf(stderr, "\n");
140 		}
141 	}
142 	return (tmp);
143 }
144 #endif /* !defined TYPECHECK */
145 
146 static void
abbrok(const char * const abbrp,const char * const zone)147 abbrok(const char * const abbrp, const char * const zone)
148 {
149 	register const char *cp;
150 	int error = 0;
151 
152 	if (warned)
153 		return;
154 	cp = abbrp;
155 	while (isalpha(*cp) || isdigit(*cp) || *cp == '-' || *cp == '+')
156 		++cp;
157 	(void) fflush(stdout);
158 	if (cp - abbrp < 3) {
159 		(void) fprintf(stderr, gettext("%s: warning: zone \"%s\" "
160 		    "abbreviation \"%s\" has fewer than 3 alphabetics\n"),
161 		    progname, zone, abbrp);
162 		error = 1;
163 	} else if (cp - abbrp > 6) {
164 		(void) fprintf(stderr, gettext("%s: warning: zone \"%s\" "
165 		    "abbreviation \"%s\" has more than 6 characters\n"),
166 		    progname, zone, abbrp);
167 		error = 1;
168 	} else if (*cp != '\0') {
169 		(void) fprintf(stderr, gettext("%s: warning: zone \"%s\" "
170 		    "abbreviation \"%s\" has characters other than "
171 		    "alphanumerics\n"), progname, zone, abbrp);
172 		error = 1;
173 	}
174 	if (error)
175 		warned = TRUE;
176 }
177 
178 int
main(argc,argv)179 main(argc, argv)
180 int	argc;
181 char	*argv[];
182 {
183 	register int		i;
184 	register int		c;
185 	register int		vflag;
186 	register char		*cutarg;
187 	register long		cutloyear = ZDUMP_LO_YEAR;
188 	register long		cuthiyear = ZDUMP_HI_YEAR;
189 	register time_t		cutlotime;
190 	register time_t		cuthitime;
191 	time_t			now;
192 	time_t			t;
193 	time_t			newt;
194 	struct tm		tm;
195 	struct tm		newtm;
196 	register struct tm	*tmp;
197 	register struct tm	*newtmp;
198 
199 	INITIALIZE(cutlotime);
200 	INITIALIZE(cuthitime);
201 
202 	(void) setlocale(LC_ALL, "");
203 #if !defined(TEXT_DOMAIN)		/* Should be defined by cc -D */
204 #define	TEXT_DOMAIN	"SYS_TEST"	/* Use this only if it weren't */
205 #endif
206 	(void) textdomain(TEXT_DOMAIN);
207 
208 	progname = argv[0];
209 	for (i = 1; i < argc; ++i)
210 		if (strcmp(argv[i], "--version") == 0) {
211 			(void) printf("%s\n", elsieid);
212 			exit(EXIT_SUCCESS);
213 		}
214 	vflag = 0;
215 	cutarg = NULL;
216 	while ((c = getopt(argc, argv, "c:v")) == 'c' || c == 'v')
217 		if (c == 'v')
218 			vflag = 1;
219 		else	cutarg = optarg;
220 	if (c != EOF ||
221 		(optind == argc - 1 && strcmp(argv[optind], "=") == 0)) {
222 			usage();
223 			/* NOTREACHED */
224 	}
225 	if (vflag) {
226 		if (cutarg != NULL) {
227 			long	lo;
228 			long	hi;
229 			char	dummy;
230 
231 			if (sscanf(cutarg, "%ld%c", &hi, &dummy) == 1) {
232 				cuthiyear = hi;
233 			} else if (sscanf(cutarg, "%ld,%ld%c",
234 				&lo, &hi, &dummy) == 2) {
235 					cutloyear = lo;
236 					cuthiyear = hi;
237 			} else {
238 				(void) fprintf(stderr,
239 				    gettext("%s: wild -c argument %s\n"),
240 				    progname, cutarg);
241 				exit(EXIT_FAILURE);
242 			}
243 		}
244 		setabsolutes();
245 		cutlotime = yeartot(cutloyear);
246 		cuthitime = yeartot(cuthiyear);
247 	}
248 	(void) time(&now);
249 	longest = 0;
250 	for (i = optind; i < argc; ++i)
251 		if (strlen(argv[i]) > longest)
252 			longest = strlen(argv[i]);
253 
254 	for (i = optind; i < argc; ++i) {
255 		static char	buf[MAX_STRING_LENGTH];
256 		static char	*tzp = NULL;
257 
258 		(void) unsetenv("TZ");
259 		if (tzp != NULL)
260 			free(tzp);
261 		if ((tzp = malloc(3 + strlen(argv[i]) + 1)) == NULL) {
262 			perror(progname);
263 			exit(EXIT_FAILURE);
264 		}
265 		(void) strcpy(tzp, "TZ=");
266 		(void) strcat(tzp, argv[i]);
267 		if (putenv(tzp) != 0) {
268 			perror(progname);
269 			exit(EXIT_FAILURE);
270 		}
271 		if (!vflag) {
272 			show(argv[i], now, FALSE);
273 			continue;
274 		}
275 
276 #if defined(sun)
277 		/*
278 		 * We show the current time first, probably because we froze
279 		 * the behavior of zdump some time ago and then it got
280 		 * changed.
281 		 */
282 		show(argv[i], now, TRUE);
283 #endif
284 		warned = FALSE;
285 		t = absolute_min_time;
286 		show(argv[i], t, TRUE);
287 		t += SECSPERHOUR * HOURSPERDAY;
288 		show(argv[i], t, TRUE);
289 		if (t < cutlotime)
290 			t = cutlotime;
291 		tmp = my_localtime(&t);
292 		if (tmp != NULL) {
293 			tm = *tmp;
294 			(void) strncpy(buf, abbr(&tm), sizeof (buf) - 1);
295 		}
296 		for (;;) {
297 			if (t >= cuthitime)
298 				break;
299 			/* check if newt will overrun maximum time_t value */
300 			if (t > LONG_MAX - (SECSPERHOUR * 12))
301 				break;
302 			newt = t + SECSPERHOUR * 12;
303 			if (newt >= cuthitime)
304 				break;
305 			newtmp = localtime(&newt);
306 			if (newtmp != NULL)
307 				newtm = *newtmp;
308 			if ((tmp == NULL || newtmp == NULL) ? (tmp != newtmp) :
309 				(delta(&newtm, &tm) != (newt - t) ||
310 				newtm.tm_isdst != tm.tm_isdst ||
311 				strcmp(abbr(&newtm), buf) != 0)) {
312 					newt = hunt(argv[i], t, newt);
313 					newtmp = localtime(&newt);
314 					if (newtmp != NULL) {
315 						newtm = *newtmp;
316 						(void) strncpy(buf,
317 							abbr(&newtm),
318 							sizeof (buf) - 1);
319 					}
320 			}
321 			t = newt;
322 			tm = newtm;
323 			tmp = newtmp;
324 		}
325 		t = absolute_max_time;
326 #if defined(sun)
327 		show(argv[i], t, TRUE);
328 		t -= SECSPERHOUR * HOURSPERDAY;
329 		show(argv[i], t, TRUE);
330 #else /* !defined(sun) */
331 		t -= SECSPERHOUR * HOURSPERDAY;
332 		show(argv[i], t, TRUE);
333 		t += SECSPERHOUR * HOURSPERDAY;
334 		show(argv[i], t, TRUE);
335 #endif /* !defined(sun) */
336 	}
337 	if (fflush(stdout) || ferror(stdout)) {
338 		(void) fprintf(stderr, "%s: ", progname);
339 		(void) perror(gettext("Error writing standard output"));
340 		exit(EXIT_FAILURE);
341 	}
342 	return (EXIT_SUCCESS);
343 }
344 
345 static void
setabsolutes()346 setabsolutes()
347 {
348 #if defined(sun)
349 	absolute_min_time = LONG_MIN;
350 	absolute_max_time = LONG_MAX;
351 #else
352 	if (0.5 == (time_t)0.5) {
353 		/*
354 		 * time_t is floating.
355 		 */
356 		if (sizeof (time_t) == sizeof (float)) {
357 			absolute_min_time = (time_t)-FLT_MAX;
358 			absolute_max_time = (time_t)FLT_MAX;
359 		} else if (sizeof (time_t) == sizeof (double)) {
360 			absolute_min_time = (time_t)-DBL_MAX;
361 			absolute_max_time = (time_t)DBL_MAX;
362 		} else {
363 			(void) fprintf(stderr, gettext("%s: use of -v on "
364 			    "system with floating time_t other than float "
365 			    "or double\n"), progname);
366 			exit(EXIT_FAILURE);
367 		}
368 	} else
369 	/*CONSTANTCONDITION*/
370 	if (0 > (time_t)-1) {
371 		/*
372 		 * time_t is signed.
373 		 */
374 		register time_t	hibit;
375 
376 		for (hibit = 1; (hibit * 2) != 0; hibit *= 2)
377 			continue;
378 		absolute_min_time = hibit;
379 		absolute_max_time = -(hibit + 1);
380 	} else {
381 		/*
382 		 * time_t is unsigned.
383 		 */
384 		absolute_min_time = 0;
385 		absolute_max_time = absolute_min_time - 1;
386 	}
387 #endif
388 }
389 
390 static time_t
yeartot(y)391 yeartot(y)
392 const long	y;
393 {
394 	register long	myy;
395 	register long	seconds;
396 	register time_t	t;
397 
398 	myy = EPOCH_YEAR;
399 	t = 0;
400 	while (myy != y) {
401 		if (myy < y) {
402 			seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
403 			++myy;
404 			if (t > absolute_max_time - seconds) {
405 				t = absolute_max_time;
406 				break;
407 			}
408 			t += seconds;
409 		} else {
410 			--myy;
411 			seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
412 			if (t < absolute_min_time + seconds) {
413 				t = absolute_min_time;
414 				break;
415 			}
416 			t -= seconds;
417 		}
418 	}
419 	return (t);
420 }
421 
422 static time_t
hunt(name,lot,hit)423 hunt(name, lot, hit)
424 char	*name;
425 time_t	lot;
426 time_t	hit;
427 {
428 	time_t			t;
429 	long			diff;
430 	struct tm		lotm;
431 	register struct tm	*lotmp;
432 	struct tm		tm;
433 	register struct tm	*tmp;
434 	char			loab[MAX_STRING_LENGTH];
435 
436 	lotmp = my_localtime(&lot);
437 	if (lotmp != NULL) {
438 		lotm = *lotmp;
439 		(void) strncpy(loab, abbr(&lotm), sizeof (loab) - 1);
440 	}
441 	for (;;) {
442 		diff = (long)(hit - lot);
443 		if (diff < 2)
444 			break;
445 		t = lot;
446 		t += diff / 2;
447 		if (t <= lot)
448 			++t;
449 		else if (t >= hit)
450 			--t;
451 		tmp = my_localtime(&t);
452 		if (tmp != NULL)
453 			tm = *tmp;
454 		if ((lotmp == NULL || tmp == NULL) ? (lotmp == tmp) :
455 			(delta(&tm, &lotm) == (t - lot) &&
456 			tm.tm_isdst == lotm.tm_isdst &&
457 			strcmp(abbr(&tm), loab) == 0)) {
458 				lot = t;
459 				lotm = tm;
460 				lotmp = tmp;
461 		} else	hit = t;
462 	}
463 	show(name, lot, TRUE);
464 	show(name, hit, TRUE);
465 	return (hit);
466 }
467 
468 /*
469  * Thanks to Paul Eggert for logic used in delta.
470  */
471 
472 static long
delta(newp,oldp)473 delta(newp, oldp)
474 struct tm	*newp;
475 struct tm	*oldp;
476 {
477 	register long	result;
478 	register int	tmy;
479 
480 	if (newp->tm_year < oldp->tm_year)
481 		return (-delta(oldp, newp));
482 	result = 0;
483 	for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy)
484 		result += DAYSPERNYEAR + isleap_sum(tmy, TM_YEAR_BASE);
485 	result += newp->tm_yday - oldp->tm_yday;
486 	result *= HOURSPERDAY;
487 	result += newp->tm_hour - oldp->tm_hour;
488 	result *= MINSPERHOUR;
489 	result += newp->tm_min - oldp->tm_min;
490 	result *= SECSPERMIN;
491 	result += newp->tm_sec - oldp->tm_sec;
492 	return (result);
493 }
494 
495 static void
show(zone,t,v)496 show(zone, t, v)
497 char	*zone;
498 time_t	t;
499 int	v;
500 {
501 	register struct tm	*tmp;
502 
503 	(void) printf("%-*s  ", (int)longest, zone);
504 	if (v) {
505 		tmp = gmtime(&t);
506 		if (tmp == NULL) {
507 			(void) printf(tformat(), t);
508 		} else {
509 			dumptime(tmp);
510 			(void) printf(" UTC");
511 		}
512 		(void) printf(" = ");
513 	}
514 	tmp = my_localtime(&t);
515 	dumptime(tmp);
516 	if (tmp != NULL) {
517 		if (*abbr(tmp) != '\0')
518 			(void) printf(" %s", abbr(tmp));
519 		if (v) {
520 			(void) printf(" isdst=%d", tmp->tm_isdst);
521 #ifdef TM_GMTOFF
522 			(void) printf(" gmtoff=%ld", tmp->TM_GMTOFF);
523 #endif /* defined TM_GMTOFF */
524 		}
525 	}
526 	(void) printf("\n");
527 	if (tmp != NULL && *abbr(tmp) != '\0')
528 		abbrok(abbr(tmp), zone);
529 }
530 
531 static char *
abbr(tmp)532 abbr(tmp)
533 struct tm	*tmp;
534 {
535 	register char	*result;
536 	static char	nada;
537 
538 	if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1)
539 		return (&nada);
540 	result = tzname[tmp->tm_isdst];
541 	return ((result == NULL) ? &nada : result);
542 }
543 
544 /*
545  * The code below can fail on certain theoretical systems;
546  * it works on all known real-world systems as of 2004-12-30.
547  */
548 
549 static const char *
tformat()550 tformat()
551 {
552 #if defined(sun)
553 	/* time_t is signed long */
554 	return ("%ld");
555 #else
556 	/*CONSTANTCONDITION*/
557 	if (0.5 == (time_t)0.5) {	/* floating */
558 		/*CONSTANTCONDITION*/
559 		if (sizeof (time_t) > sizeof (double))
560 			return ("%Lg");
561 		return ("%g");
562 	}
563 	/*CONSTANTCONDITION*/
564 	if (0 > (time_t)-1) {		/* signed */
565 		/*CONSTANTCONDITION*/
566 		if (sizeof (time_t) > sizeof (long))
567 			return ("%lld");
568 		/*CONSTANTCONDITION*/
569 		if (sizeof (time_t) > sizeof (int))
570 			return ("%ld");
571 		return ("%d");
572 	}
573 	/*CONSTANTCONDITION*/
574 	if (sizeof (time_t) > sizeof (unsigned long))
575 		return ("%llu");
576 	/*CONSTANTCONDITION*/
577 	if (sizeof (time_t) > sizeof (unsigned int))
578 		return ("%lu");
579 	return ("%u");
580 #endif
581 }
582 
583 static void
dumptime(timeptr)584 dumptime(timeptr)
585 register const struct tm	*timeptr;
586 {
587 	static const char	wday_name[][3] = {
588 		"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
589 	};
590 	static const char	mon_name[][3] = {
591 		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
592 		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
593 	};
594 	register const char	*wn;
595 	register const char	*mn;
596 	register int		lead;
597 	register int		trail;
598 
599 	if (timeptr == NULL) {
600 		(void) printf("NULL");
601 		return;
602 	}
603 	/*
604 	 * The packaged versions of localtime and gmtime never put out-of-range
605 	 * values in tm_wday or tm_mon, but since this code might be compiled
606 	 * with other (perhaps experimental) versions, paranoia is in order.
607 	 */
608 	if (timeptr->tm_wday < 0 || timeptr->tm_wday >=
609 		(int)(sizeof (wday_name) / sizeof (wday_name[0])))
610 			wn = "???";
611 	else		wn = wday_name[timeptr->tm_wday];
612 	if (timeptr->tm_mon < 0 || timeptr->tm_mon >=
613 		(int)(sizeof (mon_name) / sizeof (mon_name[0])))
614 			mn = "???";
615 	else		mn = mon_name[timeptr->tm_mon];
616 	(void) printf("%.3s %.3s%3d %.2d:%.2d:%.2d ",
617 		wn, mn,
618 		timeptr->tm_mday, timeptr->tm_hour,
619 		timeptr->tm_min, timeptr->tm_sec);
620 #define	DIVISOR	10
621 	trail = timeptr->tm_year % DIVISOR + TM_YEAR_BASE % DIVISOR;
622 	lead = timeptr->tm_year / DIVISOR + TM_YEAR_BASE / DIVISOR +
623 		trail / DIVISOR;
624 	trail %= DIVISOR;
625 	if (trail < 0 && lead > 0) {
626 		trail += DIVISOR;
627 		--lead;
628 	} else if (lead < 0 && trail > 0) {
629 		trail -= DIVISOR;
630 		++lead;
631 	}
632 	if (lead == 0)
633 		(void) printf("%d", trail);
634 	else
635 		(void) printf("%d%d", lead, ((trail < 0) ? -trail : trail));
636 }
637 
638 static void
usage()639 usage()
640 {
641 	(void) fprintf(stderr, gettext(
642 	    "%s: [ --version ] [ -v ] [ -c [loyear,]hiyear ] zonename ...\n"),
643 		progname);
644 	exit(EXIT_FAILURE);
645 	/* NOTREACHED */
646 }
647