summaryrefslogtreecommitdiff
path: root/timezone/zdump.c
blob: d525da1baeaa8babff74360a676ccd883580081e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
static char	elsieid[] = "@(#)zdump.c	7.74";

/*
** This code has been made independent of the rest of the time
** conversion package to increase confidence in the verification it provides.
** You can use this code to help in verifying other implementations.
*/

#include "stdio.h"	/* for stdout, stderr, perror */
#include "string.h"	/* for strcpy */
#include "sys/types.h"	/* for time_t */
#include "time.h"	/* for struct tm */
#include "stdlib.h"	/* for exit, malloc, atoi */
#include "float.h"	/* for FLT_MAX and DBL_MAX */
#include "ctype.h"	/* for isalpha et al. */
#ifndef isascii
#define isascii(x) 1
#endif

#ifndef ZDUMP_LO_YEAR
#define ZDUMP_LO_YEAR	(-500)
#endif /* !defined ZDUMP_LO_YEAR */

#ifndef ZDUMP_HI_YEAR
#define ZDUMP_HI_YEAR	2500
#endif /* !defined ZDUMP_HI_YEAR */

#ifndef MAX_STRING_LENGTH
#define MAX_STRING_LENGTH	1024
#endif /* !defined MAX_STRING_LENGTH */

#ifndef TRUE
#define TRUE		1
#endif /* !defined TRUE */

#ifndef FALSE
#define FALSE		0
#endif /* !defined FALSE */

#ifndef EXIT_SUCCESS
#define EXIT_SUCCESS	0
#endif /* !defined EXIT_SUCCESS */

#ifndef EXIT_FAILURE
#define EXIT_FAILURE	1
#endif /* !defined EXIT_FAILURE */

#ifndef SECSPERMIN
#define SECSPERMIN	60
#endif /* !defined SECSPERMIN */

#ifndef MINSPERHOUR
#define MINSPERHOUR	60
#endif /* !defined MINSPERHOUR */

#ifndef SECSPERHOUR
#define SECSPERHOUR	(SECSPERMIN * MINSPERHOUR)
#endif /* !defined SECSPERHOUR */

#ifndef HOURSPERDAY
#define HOURSPERDAY	24
#endif /* !defined HOURSPERDAY */

#ifndef EPOCH_YEAR
#define EPOCH_YEAR	1970
#endif /* !defined EPOCH_YEAR */

#ifndef TM_YEAR_BASE
#define TM_YEAR_BASE	1900
#endif /* !defined TM_YEAR_BASE */

#ifndef DAYSPERNYEAR
#define DAYSPERNYEAR	365
#endif /* !defined DAYSPERNYEAR */

#ifndef isleap
#define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
#endif /* !defined isleap */

#ifndef isleap_sum
/*
** See tzfile.h for details on isleap_sum.
*/
#define isleap_sum(a, b)	isleap((a) % 400 + (b) % 400)
#endif /* !defined isleap_sum */

#define SECSPERDAY	((long) SECSPERHOUR * HOURSPERDAY)
#define SECSPERNYEAR	(SECSPERDAY * DAYSPERNYEAR)
#define SECSPERLYEAR	(SECSPERNYEAR + SECSPERDAY)

#if HAVE_GETTEXT
#include "locale.h"	/* for setlocale */
#include "libintl.h"
#endif /* HAVE_GETTEXT */

#ifndef GNUC_or_lint
#ifdef lint
#define GNUC_or_lint
#else /* !defined lint */
#ifdef __GNUC__
#define GNUC_or_lint
#endif /* defined __GNUC__ */
#endif /* !defined lint */
#endif /* !defined GNUC_or_lint */

#ifndef INITIALIZE
#ifdef GNUC_or_lint
#define INITIALIZE(x)	((x) = 0)
#else /* !defined GNUC_or_lint */
#define INITIALIZE(x)
#endif /* !defined GNUC_or_lint */
#endif /* !defined INITIALIZE */

/*
** For the benefit of GNU folk...
** `_(MSGID)' uses the current locale's message library string for MSGID.
** The default is to use gettext if available, and use MSGID otherwise.
*/

#ifndef _
#if HAVE_GETTEXT
#define _(msgid) gettext(msgid)
#else /* !HAVE_GETTEXT */
#define _(msgid) msgid
#endif /* !HAVE_GETTEXT */
#endif /* !defined _ */

#ifndef TZ_DOMAIN
#define TZ_DOMAIN "tz"
#endif /* !defined TZ_DOMAIN */

#ifndef P
#ifdef __STDC__
#define P(x)	x
#else /* !defined __STDC__ */
#define P(x)	()
#endif /* !defined __STDC__ */
#endif /* !defined P */

extern char **	environ;
extern int	getopt P((int argc, char * const argv[],
			const char * options));
extern char *	optarg;
extern int	optind;
extern char *	tzname[2];

static time_t	absolute_min_time;
static time_t	absolute_max_time;
static size_t	longest;
static char *	progname;
static int	warned;

static char *	abbr P((struct tm * tmp));
static void	abbrok P((const char * abbrp, const char * zone));
static long	delta P((struct tm * newp, struct tm * oldp));
static void	dumptime P((const struct tm * tmp));
static time_t	hunt P((char * name, time_t lot, time_t	hit));
static void	setabsolutes P((void));
static void	show P((char * zone, time_t t, int v));
static const char *	tformat P((void));
static time_t	yeartot P((long y));

#ifndef TYPECHECK
#define my_localtime	localtime
#else /* !defined TYPECHECK */
static struct tm *
my_localtime(tp)
time_t *	tp;
{
	register struct tm *	tmp;

	tmp = localtime(tp);
	if (tp != NULL && tmp != NULL) {
		struct tm	tm;
		register time_t	t;

		tm = *tmp;
		t = mktime(&tm);
		if (t - *tp >= 1 || *tp - t >= 1) {
			(void) fflush(stdout);
			(void) fprintf(stderr, "\n%s: ", progname);
			(void) fprintf(stderr, tformat(), *tp);
			(void) fprintf(stderr, " ->");
			(void) fprintf(stderr, " year=%d", tmp->tm_year);
			(void) fprintf(stderr, " mon=%d", tmp->tm_mon);
			(void) fprintf(stderr, " mday=%d", tmp->tm_mday);
			(void) fprintf(stderr, " hour=%d", tmp->tm_hour);
			(void) fprintf(stderr, " min=%d", tmp->tm_min);
			(void) fprintf(stderr, " sec=%d", tmp->tm_sec);
			(void) fprintf(stderr, " isdst=%d", tmp->tm_isdst);
			(void) fprintf(stderr, " -> ");
			(void) fprintf(stderr, tformat(), t);
			(void) fprintf(stderr, "\n");
		}
	}
	return tmp;
}
#endif /* !defined TYPECHECK */

static void
abbrok(abbrp, zone)
const char * const	abbrp;
const char * const	zone;
{
	register const char *	cp;
	register char *		wp;

	if (warned)
		return;
	cp = abbrp;
	wp = NULL;
	while (isascii((unsigned char) *cp) && isalpha((unsigned char) *cp))
		++cp;
	if (cp - abbrp == 0)
		wp = _("lacks alphabetic at start");
	else if (cp - abbrp < 3)
		wp = _("has fewer than 3 alphabetics");
	else if (cp - abbrp > 6)
		wp = _("has more than 6 alphabetics");
	if (wp == NULL && (*cp == '+' || *cp == '-')) {
		++cp;
		if (isascii((unsigned char) *cp) &&
			isdigit((unsigned char) *cp))
				if (*cp++ == '1' && *cp >= '0' && *cp <= '4')
					++cp;
		if (*cp != '\0')
			wp = _("differs from POSIX standard");
	}
	if (wp == NULL)
		return;
	(void) fflush(stdout);
	(void) fprintf(stderr,
		_("%s: warning: zone \"%s\" abbreviation \"%s\" %s\n"),
		progname, zone, abbrp, wp);
	warned = TRUE;
}

int
main(argc, argv)
int	argc;
char *	argv[];
{
	register int		i;
	register int		c;
	register int		vflag;
	register char *		cutarg;
	register long		cutloyear = ZDUMP_LO_YEAR;
	register long		cuthiyear = ZDUMP_HI_YEAR;
	register time_t		cutlotime;
	register time_t		cuthitime;
	register char **	fakeenv;
	time_t			now;
	time_t			t;
	time_t			newt;
	struct tm		tm;
	struct tm		newtm;
	register struct tm *	tmp;
	register struct tm *	newtmp;

	INITIALIZE(cutlotime);
	INITIALIZE(cuthitime);
#if HAVE_GETTEXT
	(void) setlocale(LC_ALL, "");
#ifdef TZ_DOMAINDIR
	(void) bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR);
#endif /* defined TEXTDOMAINDIR */
	(void) textdomain(TZ_DOMAIN);
#endif /* HAVE_GETTEXT */
	progname = argv[0];
	for (i = 1; i < argc; ++i)
		if (strcmp(argv[i], "--version") == 0) {
			(void) printf("%s\n", elsieid);
			exit(EXIT_SUCCESS);
		}
	vflag = 0;
	cutarg = NULL;
	while ((c = getopt(argc, argv, "c:v")) == 'c' || c == 'v')
		if (c == 'v')
			vflag = 1;
		else	cutarg = optarg;
	if ((c != EOF && c != -1) ||
		(optind == argc - 1 && strcmp(argv[optind], "=") == 0)) {
			(void) fprintf(stderr,
_("%s: usage is %s [ --version ] [ -v ] [ -c [loyear,]hiyear ] zonename ...\n"),
				progname, progname);
			exit(EXIT_FAILURE);
	}
	if (vflag) {
		if (cutarg != NULL) {
			long	lo;
			long	hi;
			char	dummy;

			if (sscanf(cutarg, "%ld%c", &hi, &dummy) == 1) {
				cuthiyear = hi;
			} else if (sscanf(cutarg, "%ld,%ld%c",
				&lo, &hi, &dummy) == 2) {
					cutloyear = lo;
					cuthiyear = hi;
			} else {
(void) fprintf(stderr, _("%s: wild -c argument %s\n"),
					progname, cutarg);
				exit(EXIT_FAILURE);
			}
		}
		setabsolutes();
		cutlotime = yeartot(cutloyear);
		cuthitime = yeartot(cuthiyear);
	}
	(void) time(&now);
	longest = 0;
	for (i = optind; i < argc; ++i)
		if (strlen(argv[i]) > longest)
			longest = strlen(argv[i]);
	{
		register int	from;
		register int	to;

		for (i = 0; environ[i] != NULL; ++i)
			continue;
		fakeenv = (char **) malloc((size_t) ((i + 2) *
			sizeof *fakeenv));
		if (fakeenv == NULL ||
			(fakeenv[0] = (char *) malloc(longest + 4)) == NULL) {
					(void) perror(progname);
					exit(EXIT_FAILURE);
		}
		to = 0;
		(void) strcpy(fakeenv[to++], "TZ=");
		for (from = 0; environ[from] != NULL; ++from)
			if (strncmp(environ[from], "TZ=", 3) != 0)
				fakeenv[to++] = environ[from];
		fakeenv[to] = NULL;
		environ = fakeenv;
	}
	for (i = optind; i < argc; ++i) {
		static char	buf[MAX_STRING_LENGTH];

		(void) strcpy(&fakeenv[0][3], argv[i]);
		if (!vflag) {
			show(argv[i], now, FALSE);
			continue;
		}
		warned = FALSE;
		t = absolute_min_time;
		show(argv[i], t, TRUE);
		t += SECSPERHOUR * HOURSPERDAY;
		show(argv[i], t, TRUE);
		if (t < cutlotime)
			t = cutlotime;
		tmp = my_localtime(&t);
		if (tmp != NULL) {
			tm = *tmp;
			(void) strncpy(buf, abbr(&tm), (sizeof buf) - 1);
		}
		for ( ; ; ) {
			if (t >= cuthitime)
				break;
			newt = t + SECSPERHOUR * 12;
			if (newt >= cuthitime)
				break;
			if (newt <= t)
				break;
			newtmp = localtime(&newt);
			if (newtmp != NULL)
				newtm = *newtmp;
			if ((tmp == NULL || newtmp == NULL) ? (tmp != newtmp) :
				(delta(&newtm, &tm) != (newt - t) ||
				newtm.tm_isdst != tm.tm_isdst ||
				strcmp(abbr(&newtm), buf) != 0)) {
					newt = hunt(argv[i], t, newt);
					newtmp = localtime(&newt);
					if (newtmp != NULL) {
						newtm = *newtmp;
						(void) strncpy(buf,
							abbr(&newtm),
							(sizeof buf) - 1);
					}
			}
			t = newt;
			tm = newtm;
			tmp = newtmp;
		}
		t = absolute_max_time;
		t -= SECSPERHOUR * HOURSPERDAY;
		show(argv[i], t, TRUE);
		t += SECSPERHOUR * HOURSPERDAY;
		show(argv[i], t, TRUE);
	}
	if (fflush(stdout) || ferror(stdout)) {
		(void) fprintf(stderr, "%s: ", progname);
		(void) perror(_("Error writing to standard output"));
		exit(EXIT_FAILURE);
	}
	exit(EXIT_SUCCESS);
	/* If exit fails to exit... */
	return EXIT_FAILURE;
}

static void
setabsolutes()
{
	if (0.5 == (time_t) 0.5) {
		/*
		** time_t is floating.
		*/
		if (sizeof (time_t) == sizeof (float)) {
			absolute_min_time = (time_t) -FLT_MAX;
			absolute_max_time = (time_t) FLT_MAX;
		} else if (sizeof (time_t) == sizeof (double)) {
			absolute_min_time = (time_t) -DBL_MAX;
			absolute_max_time = (time_t) DBL_MAX;
		} else {
			(void) fprintf(stderr,
_("%s: use of -v on system with floating time_t other than float or double\n"),
				progname);
			exit(EXIT_FAILURE);
		}
	} else if (0 > (time_t) -1) {
		/*
		** time_t is signed.
		*/
		register time_t	hibit;

		for (hibit = 1; (hibit * 2) != 0; hibit *= 2)
			continue;
		absolute_min_time = hibit;
		absolute_max_time = -(hibit + 1);
	} else {
		/*
		** time_t is unsigned.
		*/
		absolute_min_time = 0;
		absolute_max_time = absolute_min_time - 1;
	}
}

static time_t
yeartot(y)
const long	y;
{
	register long	myy;
	register long	seconds;
	register time_t	t;

	myy = EPOCH_YEAR;
	t = 0;
	while (myy != y) {
		if (myy < y) {
			seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
			++myy;
			if (t > absolute_max_time - seconds) {
				t = absolute_max_time;
				break;
			}
			t += seconds;
		} else {
			--myy;
			seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
			if (t < absolute_min_time + seconds) {
				t = absolute_min_time;
				break;
			}
			t -= seconds;
		}
	}
	return t;
}

static time_t
hunt(name, lot, hit)
char *	name;
time_t	lot;
time_t	hit;
{
	time_t			t;
	long			diff;
	struct tm		lotm;
	register struct tm *	lotmp;
	struct tm		tm;
	register struct tm *	tmp;
	char			loab[MAX_STRING_LENGTH];

	lotmp = my_localtime(&lot);
	if (lotmp != NULL) {
		lotm = *lotmp;
		(void) strncpy(loab, abbr(&lotm), (sizeof loab) - 1);
	}
	for ( ; ; ) {
		diff = (long) (hit - lot);
		if (diff < 2)
			break;
		t = lot;
		t += diff / 2;
		if (t <= lot)
			++t;
		else if (t >= hit)
			--t;
		tmp = my_localtime(&t);
		if (tmp != NULL)
			tm = *tmp;
		if ((lotmp == NULL || tmp == NULL) ? (lotmp == tmp) :
			(delta(&tm, &lotm) == (t - lot) &&
			tm.tm_isdst == lotm.tm_isdst &&
			strcmp(abbr(&tm), loab) == 0)) {
				lot = t;
				lotm = tm;
				lotmp = tmp;
		} else	hit = t;
	}
	show(name, lot, TRUE);
	show(name, hit, TRUE);
	return hit;
}

/*
** Thanks to Paul Eggert for logic used in delta.
*/

static long
delta(newp, oldp)
struct tm *	newp;
struct tm *	oldp;
{
	register long	result;
	register int	tmy;

	if (newp->tm_year < oldp->tm_year)
		return -delta(oldp, newp);
	result = 0;
	for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy)
		result += DAYSPERNYEAR + isleap_sum(tmy, TM_YEAR_BASE);
	result += newp->tm_yday - oldp->tm_yday;
	result *= HOURSPERDAY;
	result += newp->tm_hour - oldp->tm_hour;
	result *= MINSPERHOUR;
	result += newp->tm_min - oldp->tm_min;
	result *= SECSPERMIN;
	result += newp->tm_sec - oldp->tm_sec;
	return result;
}

static void
show(zone, t, v)
char *	zone;
time_t	t;
int	v;
{
	register struct tm *	tmp;

	(void) printf("%-*s  ", (int) longest, zone);
	if (v) {
		tmp = gmtime(&t);
		if (tmp == NULL) {
			(void) printf(tformat(), t);
		} else {
			dumptime(tmp);
			(void) printf(" UTC");
		}
		(void) printf(" = ");
	}
	tmp = my_localtime(&t);
	dumptime(tmp);
	if (tmp != NULL) {
		if (*abbr(tmp) != '\0')
			(void) printf(" %s", abbr(tmp));
		if (v) {
			(void) printf(" isdst=%d", tmp->tm_isdst);
#ifdef TM_GMTOFF
			(void) printf(" gmtoff=%ld", tmp->TM_GMTOFF);
#endif /* defined TM_GMTOFF */
		}
	}
	(void) printf("\n");
	if (tmp != NULL && *abbr(tmp) != '\0')
		abbrok(abbr(tmp), zone);
}

static char *
abbr(tmp)
struct tm *	tmp;
{
	register char *	result;
	static char	nada;

	if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1)
		return &nada;
	result = tzname[tmp->tm_isdst];
	return (result == NULL) ? &nada : result;
}

/*
** The code below can fail on certain theoretical systems;
** it works on all known real-world systems as of 2004-12-30.
*/

static const char *
tformat()
{
	if (0.5 == (time_t) 0.5) {	/* floating */
		if (sizeof (time_t) > sizeof (double))
			return "%Lg";
		return "%g";
	}
	if (0 > (time_t) -1) {		/* signed */
		if (sizeof (time_t) > sizeof (long))
			return "%lld";
		if (sizeof (time_t) > sizeof (int))
			return "%ld";
		return "%d";
	}
	if (sizeof (time_t) > sizeof (unsigned long))
		return "%llu";
	if (sizeof (time_t) > sizeof (unsigned int))
		return "%lu";
	return "%u";
}

static void
dumptime(timeptr)
register const struct tm *	timeptr;
{
	static const char	wday_name[][3] = {
		"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
	};
	static const char	mon_name[][3] = {
		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
	};
	register const char *	wn;
	register const char *	mn;
	register int		lead;
	register int		trail;

	if (timeptr == NULL) {
		(void) printf("NULL");
		return;
	}
	/*
	** The packaged versions of localtime and gmtime never put out-of-range
	** values in tm_wday or tm_mon, but since this code might be compiled
	** with other (perhaps experimental) versions, paranoia is in order.
	*/
	if (timeptr->tm_wday < 0 || timeptr->tm_wday >=
		(int) (sizeof wday_name / sizeof wday_name[0]))
			wn = "???";
	else		wn = wday_name[timeptr->tm_wday];
	if (timeptr->tm_mon < 0 || timeptr->tm_mon >=
		(int) (sizeof mon_name / sizeof mon_name[0]))
			mn = "???";
	else		mn = mon_name[timeptr->tm_mon];
	(void) printf("%.3s %.3s%3d %.2d:%.2d:%.2d ",
		wn, mn,
		timeptr->tm_mday, timeptr->tm_hour,
		timeptr->tm_min, timeptr->tm_sec);
#define DIVISOR	10
	trail = timeptr->tm_year % DIVISOR + TM_YEAR_BASE % DIVISOR;
	lead = timeptr->tm_year / DIVISOR + TM_YEAR_BASE / DIVISOR +
		trail / DIVISOR;
	trail %= DIVISOR;
	if (trail < 0 && lead > 0) {
		trail += DIVISOR;
		--lead;
	} else if (lead < 0 && trail > 0) {
		trail -= DIVISOR;
		++lead;
	}
	if (lead == 0)
		(void) printf("%d", trail);
	else	(void) printf("%d%d", lead, ((trail < 0) ? -trail : trail));
}