1/*	$NetBSD: zdump.c,v 1.23 2011/09/04 13:25:22 christos Exp $	*/
2/*
3** This file is in the public domain, so clarified as of
4** 2009-05-17 by Arthur David Olson.
5*/
6
7#include <sys/cdefs.h>
8#ifndef lint
9#ifndef NOID
10__RCSID("$NetBSD: zdump.c,v 1.23 2011/09/04 13:25:22 christos Exp $");
11#endif /* !defined NOID */
12#endif /* !defined lint */
13
14static char	elsieid[] = "@(#)zdump.c	8.10";
15
16/*
17** This code has been made independent of the rest of the time
18** conversion package to increase confidence in the verification it provides.
19** You can use this code to help in verifying other implementations.
20*/
21
22#include "stdio.h"	/* for stdout, stderr */
23#include "string.h"	/* for strcpy */
24#include "sys/types.h"	/* for time_t */
25#include "time.h"	/* for struct tm */
26#include "stdlib.h"	/* for exit, malloc, atoi */
27#include <err.h>
28#include "float.h"	/* for FLT_MAX and DBL_MAX */
29#include "ctype.h"	/* for isalpha et al. */
30#ifndef isascii
31#define isascii(x) 1
32#endif /* !defined isascii */
33
34#ifndef ZDUMP_LO_YEAR
35#define ZDUMP_LO_YEAR	(-500)
36#endif /* !defined ZDUMP_LO_YEAR */
37
38#ifndef ZDUMP_HI_YEAR
39#define ZDUMP_HI_YEAR	2500
40#endif /* !defined ZDUMP_HI_YEAR */
41
42#ifndef MAX_STRING_LENGTH
43#define MAX_STRING_LENGTH	1024
44#endif /* !defined MAX_STRING_LENGTH */
45
46#ifndef TRUE
47#define TRUE		1
48#endif /* !defined TRUE */
49
50#ifndef FALSE
51#define FALSE		0
52#endif /* !defined FALSE */
53
54#ifndef EXIT_SUCCESS
55#define EXIT_SUCCESS	0
56#endif /* !defined EXIT_SUCCESS */
57
58#ifndef EXIT_FAILURE
59#define EXIT_FAILURE	1
60#endif /* !defined EXIT_FAILURE */
61
62#ifndef SECSPERMIN
63#define SECSPERMIN	60
64#endif /* !defined SECSPERMIN */
65
66#ifndef MINSPERHOUR
67#define MINSPERHOUR	60
68#endif /* !defined MINSPERHOUR */
69
70#ifndef SECSPERHOUR
71#define SECSPERHOUR	(SECSPERMIN * MINSPERHOUR)
72#endif /* !defined SECSPERHOUR */
73
74#ifndef HOURSPERDAY
75#define HOURSPERDAY	24
76#endif /* !defined HOURSPERDAY */
77
78#ifndef EPOCH_YEAR
79#define EPOCH_YEAR	1970
80#endif /* !defined EPOCH_YEAR */
81
82#ifndef TM_YEAR_BASE
83#define TM_YEAR_BASE	1900
84#endif /* !defined TM_YEAR_BASE */
85
86#ifndef DAYSPERNYEAR
87#define DAYSPERNYEAR	365
88#endif /* !defined DAYSPERNYEAR */
89
90#ifndef isleap
91#define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
92#endif /* !defined isleap */
93
94#ifndef isleap_sum
95/*
96** See tzfile.h for details on isleap_sum.
97*/
98#define isleap_sum(a, b)	isleap((a) % 400 + (b) % 400)
99#endif /* !defined isleap_sum */
100
101#define SECSPERDAY	((long) SECSPERHOUR * HOURSPERDAY)
102#define SECSPERNYEAR	(SECSPERDAY * DAYSPERNYEAR)
103#define SECSPERLYEAR	(SECSPERNYEAR + SECSPERDAY)
104
105#ifndef HAVE_GETTEXT
106#define HAVE_GETTEXT 0
107#endif
108#if HAVE_GETTEXT
109#include "locale.h"	/* for setlocale */
110#include "libintl.h"
111#endif /* HAVE_GETTEXT */
112
113#ifndef GNUC_or_lint
114#ifdef lint
115#define GNUC_or_lint
116#else /* !defined lint */
117#ifdef __GNUC__
118#define GNUC_or_lint
119#endif /* defined __GNUC__ */
120#endif /* !defined lint */
121#endif /* !defined GNUC_or_lint */
122
123#ifndef INITIALIZE
124#ifdef GNUC_or_lint
125#define INITIALIZE(x)	((x) = 0)
126#else /* !defined GNUC_or_lint */
127#define INITIALIZE(x)
128#endif /* !defined GNUC_or_lint */
129#endif /* !defined INITIALIZE */
130
131/*
132** For the benefit of GNU folk...
133** `_(MSGID)' uses the current locale's message library string for MSGID.
134** The default is to use gettext if available, and use MSGID otherwise.
135*/
136
137#ifndef _
138#if HAVE_GETTEXT
139#define _(msgid) gettext(msgid)
140#else /* !HAVE_GETTEXT */
141#define _(msgid) msgid
142#endif /* !HAVE_GETTEXT */
143#endif /* !defined _ */
144
145#ifndef TZ_DOMAIN
146#define TZ_DOMAIN "tz"
147#endif /* !defined TZ_DOMAIN */
148
149extern char **	environ;
150extern int	getopt(int argc, char * const argv[],
151			const char * options);
152extern char *	optarg;
153extern int	optind;
154
155static time_t	absolute_min_time;
156static time_t	absolute_max_time;
157static size_t	longest;
158static char *	progname;
159static int	warned;
160
161static const char *	abbr(struct tm * tmp);
162static void	abbrok(const char * abbrp, const char * zone);
163static long	delta(struct tm * newp, struct tm * oldp);
164static void	dumptime(const struct tm * tmp);
165static time_t	hunt(char * name, time_t lot, time_t	hit);
166int		main(int, char **);
167static void	setabsolutes(void);
168static void	show(char * zone, time_t t, int v);
169static const char *	tformat(void);
170static time_t	yeartot(long y);
171
172#ifndef TYPECHECK
173#define my_localtime	localtime
174#else /* !defined TYPECHECK */
175static struct tm *
176my_localtime(tp)
177time_t *	tp;
178{
179	register struct tm *	tmp;
180
181	tmp = localtime(tp);
182	if (tp != NULL && tmp != NULL) {
183		struct tm	tm;
184		register time_t	t;
185
186		tm = *tmp;
187		t = mktime(&tm);
188		if (t - *tp >= 1 || *tp - t >= 1) {
189			(void) fflush(stdout);
190			(void) fprintf(stderr, "\n%s: ", progname);
191			(void) fprintf(stderr, tformat(), *tp);
192			(void) fprintf(stderr, " ->");
193			(void) fprintf(stderr, " year=%d", tmp->tm_year);
194			(void) fprintf(stderr, " mon=%d", tmp->tm_mon);
195			(void) fprintf(stderr, " mday=%d", tmp->tm_mday);
196			(void) fprintf(stderr, " hour=%d", tmp->tm_hour);
197			(void) fprintf(stderr, " min=%d", tmp->tm_min);
198			(void) fprintf(stderr, " sec=%d", tmp->tm_sec);
199			(void) fprintf(stderr, " isdst=%d", tmp->tm_isdst);
200			(void) fprintf(stderr, " -> ");
201			(void) fprintf(stderr, tformat(), t);
202			(void) fprintf(stderr, "\n");
203		}
204	}
205	return tmp;
206}
207#endif /* !defined TYPECHECK */
208
209static void
210abbrok(abbrp, zone)
211const char * const	abbrp;
212const char * const	zone;
213{
214	register const char *	cp;
215	register const char *	wp;
216
217	if (warned)
218		return;
219	cp = abbrp;
220	wp = NULL;
221	while (isascii((unsigned char) *cp) && isalpha((unsigned char) *cp))
222		++cp;
223	if (cp - abbrp == 0)
224		wp = _("lacks alphabetic at start");
225	else if (cp - abbrp < 3)
226		wp = _("has fewer than 3 alphabetics");
227	else if (cp - abbrp > 6)
228		wp = _("has more than 6 alphabetics");
229	if (wp == NULL && (*cp == '+' || *cp == '-')) {
230		++cp;
231		if (isascii((unsigned char) *cp) &&
232			isdigit((unsigned char) *cp))
233				if (*cp++ == '1' && *cp >= '0' && *cp <= '4')
234					++cp;
235		if (*cp != '\0')
236			wp = _("differs from POSIX standard");
237	}
238	if (wp == NULL)
239		return;
240	(void) fflush(stdout);
241	(void) fprintf(stderr,
242		_("%s: warning: zone \"%s\" abbreviation \"%s\" %s\n"),
243		progname, zone, abbrp, wp);
244	warned = TRUE;
245}
246
247__dead static void
248usage(FILE *stream, int status)
249{
250	(void) fprintf(stream,
251_("%s: usage is %s [ --version ] [ --help ] [ -v ] [ -c [loyear,]hiyear ] zonename ...\n\
252\n\
253Report bugs to tz@elsie.nci.nih.gov.\n"),
254		       progname, progname);
255	exit(status);
256}
257
258int
259main(argc, argv)
260int	argc;
261char *	argv[];
262{
263	register int		i;
264	register int		c;
265	register int		vflag;
266	register char *		cutarg;
267	register long		cutloyear = ZDUMP_LO_YEAR;
268	register long		cuthiyear = ZDUMP_HI_YEAR;
269	register time_t		cutlotime;
270	register time_t		cuthitime;
271	register char **	fakeenv;
272	time_t			now;
273	time_t			t;
274	time_t			newt;
275	struct tm		tm;
276	struct tm		newtm;
277	register struct tm *	tmp;
278	register struct tm *	newtmp;
279
280	INITIALIZE(cutlotime);
281	INITIALIZE(cuthitime);
282#if HAVE_GETTEXT
283	(void) setlocale(LC_ALL, "");
284#ifdef TZ_DOMAINDIR
285	(void) bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR);
286#endif /* defined TEXTDOMAINDIR */
287	(void) textdomain(TZ_DOMAIN);
288#endif /* HAVE_GETTEXT */
289	progname = argv[0];
290	for (i = 1; i < argc; ++i)
291		if (strcmp(argv[i], "--version") == 0) {
292			(void) printf("%s\n", elsieid);
293			exit(EXIT_SUCCESS);
294		} else if (strcmp(argv[i], "--help") == 0) {
295			usage(stdout, EXIT_SUCCESS);
296		}
297	vflag = 0;
298	cutarg = NULL;
299	while ((c = getopt(argc, argv, "c:v")) == 'c' || c == 'v')
300		if (c == 'v')
301			vflag = 1;
302		else	cutarg = optarg;
303	if ((c != EOF && c != -1) ||
304		(optind == argc - 1 && strcmp(argv[optind], "=") == 0)) {
305			usage(stderr, EXIT_FAILURE);
306	}
307	if (vflag) {
308		if (cutarg != NULL) {
309			long	lo;
310			long	hi;
311			char	dummy;
312
313			if (sscanf(cutarg, "%ld%c", &hi, &dummy) == 1) {
314				cuthiyear = hi;
315			} else if (sscanf(cutarg, "%ld,%ld%c",
316				&lo, &hi, &dummy) == 2) {
317					cutloyear = lo;
318					cuthiyear = hi;
319			} else {
320(void) fprintf(stderr, _("%s: wild -c argument %s\n"),
321					progname, cutarg);
322				exit(EXIT_FAILURE);
323			}
324		}
325		setabsolutes();
326		cutlotime = yeartot(cutloyear);
327		cuthitime = yeartot(cuthiyear);
328	}
329	(void) time(&now);
330	longest = 0;
331	for (i = optind; i < argc; ++i)
332		if (strlen(argv[i]) > longest)
333			longest = strlen(argv[i]);
334	{
335		register int	from;
336		register int	to;
337
338		for (i = 0; environ[i] != NULL; ++i)
339			continue;
340		fakeenv = (char **) malloc((size_t) ((i + 2) *
341			sizeof *fakeenv));
342		if (fakeenv == NULL ||
343			(fakeenv[0] = (char *) malloc(longest + 4)) == NULL) {
344			err(EXIT_FAILURE, "Can't allocated %zu bytes",
345			    longest + 4);
346		}
347		to = 0;
348		(void)strcpy(fakeenv[to++], "TZ=");	/* XXX strcpy is safe */
349		for (from = 0; environ[from] != NULL; ++from)
350			if (strncmp(environ[from], "TZ=", 3) != 0)
351				fakeenv[to++] = environ[from];
352		fakeenv[to] = NULL;
353		environ = fakeenv;
354	}
355	for (i = optind; i < argc; ++i) {
356		static char	buf[MAX_STRING_LENGTH];
357
358		(void) strcpy(&fakeenv[0][3], argv[i]);	/* XXX strcpy is safe */
359		if (!vflag) {
360			show(argv[i], now, FALSE);
361			continue;
362		}
363		warned = FALSE;
364		t = absolute_min_time;
365		show(argv[i], t, TRUE);
366		t += SECSPERHOUR * HOURSPERDAY;
367		show(argv[i], t, TRUE);
368		if (t < cutlotime)
369			t = cutlotime;
370		tmp = my_localtime(&t);
371		if (tmp != NULL) {
372			tm = *tmp;
373			(void) strncpy(buf, abbr(&tm), (sizeof buf) - 1);
374		}
375		for ( ; ; ) {
376			if (t >= cuthitime || t >= cuthitime - SECSPERHOUR * 12)
377				break;
378			newt = t + SECSPERHOUR * 12;
379			newtmp = localtime(&newt);
380			if (newtmp != NULL)
381				newtm = *newtmp;
382			if ((tmp == NULL || newtmp == NULL) ? (tmp != newtmp) :
383				(delta(&newtm, &tm) != (newt - t) ||
384				newtm.tm_isdst != tm.tm_isdst ||
385				strcmp(abbr(&newtm), buf) != 0)) {
386					newt = hunt(argv[i], t, newt);
387					newtmp = localtime(&newt);
388					if (newtmp != NULL) {
389						newtm = *newtmp;
390						(void) strncpy(buf,
391							abbr(&newtm),
392							(sizeof buf) - 1);
393					}
394			}
395			t = newt;
396			tm = newtm;
397			tmp = newtmp;
398		}
399		t = absolute_max_time;
400		t -= SECSPERHOUR * HOURSPERDAY;
401		show(argv[i], t, TRUE);
402		t += SECSPERHOUR * HOURSPERDAY;
403		show(argv[i], t, TRUE);
404	}
405	if (fflush(stdout) || ferror(stdout)) {
406		err(EXIT_FAILURE, _("Error writing standard output"));
407	}
408	exit(EXIT_SUCCESS);
409	/* If exit fails to exit... */
410	return EXIT_FAILURE;
411}
412
413static time_t
414ovfl_check(time_t t)
415{
416	if (t < 0 && t - 1 >= 0)
417		return t;
418	else
419		return t - 1;
420}
421
422static void
423setabsolutes(void)
424{
425	if (0.5 == (time_t) 0.5) {
426		/*
427		** time_t is floating.
428		*/
429		if (sizeof (time_t) == sizeof (float)) {
430			absolute_min_time = (time_t) -FLT_MAX;
431			absolute_max_time = (time_t) FLT_MAX;
432		} else if (sizeof (time_t) == sizeof (double)) {
433			absolute_min_time = (time_t) -DBL_MAX;
434			absolute_max_time = (time_t) DBL_MAX;
435		} else {
436			(void) fprintf(stderr,
437_("%s: use of -v on system with floating time_t other than float or double\n"),
438				progname);
439			exit(EXIT_FAILURE);
440		}
441	} else if (0 > (time_t) -1) {
442		/*
443		** time_t is signed.  Assume overflow wraps around.
444		*/
445		time_t t = 0;
446		time_t t1 = 1;
447
448		while (t < t1) {
449			t = t1;
450			t1 = 2 * t1 + 1;
451		}
452
453		absolute_max_time = t;
454		t = -t;
455		absolute_min_time = ovfl_check(t);
456	} else {
457		/*
458		** time_t is unsigned.
459		*/
460		absolute_min_time = 0;
461		absolute_max_time = absolute_min_time - 1;
462	}
463}
464
465static time_t
466yeartot(y)
467const long	y;
468{
469	register long	myy;
470	register long	seconds;
471	register time_t	t;
472
473	myy = EPOCH_YEAR;
474	t = 0;
475	while (myy != y) {
476		if (myy < y) {
477			seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
478			++myy;
479			if (t > absolute_max_time - seconds) {
480				t = absolute_max_time;
481				break;
482			}
483			t += seconds;
484		} else {
485			--myy;
486			seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
487			if (t < absolute_min_time + seconds) {
488				t = absolute_min_time;
489				break;
490			}
491			t -= seconds;
492		}
493	}
494	return t;
495}
496
497static time_t
498hunt(char *name, time_t lot, time_t hit)
499{
500	time_t			t;
501	long			diff;
502	struct tm		lotm;
503	register struct tm *	lotmp;
504	struct tm		tm;
505	register struct tm *	tmp;
506	char			loab[MAX_STRING_LENGTH];
507
508	lotmp = my_localtime(&lot);
509	if (lotmp != NULL) {
510		lotm = *lotmp;
511		(void) strncpy(loab, abbr(&lotm), (sizeof loab) - 1);
512	}
513	for ( ; ; ) {
514		diff = (long) (hit - lot);
515		if (diff < 2)
516			break;
517		t = lot;
518		t += diff / 2;
519		if (t <= lot)
520			++t;
521		else if (t >= hit)
522			--t;
523		tmp = my_localtime(&t);
524		if (tmp != NULL)
525			tm = *tmp;
526		if ((lotmp == NULL || tmp == NULL) ? (lotmp == tmp) :
527			(delta(&tm, &lotm) == (t - lot) &&
528			tm.tm_isdst == lotm.tm_isdst &&
529			strcmp(abbr(&tm), loab) == 0)) {
530				lot = t;
531				lotm = tm;
532				lotmp = tmp;
533		} else	hit = t;
534	}
535	show(name, lot, TRUE);
536	show(name, hit, TRUE);
537	return hit;
538}
539
540/*
541** Thanks to Paul Eggert for logic used in delta.
542*/
543
544static long
545delta(newp, oldp)
546struct tm *	newp;
547struct tm *	oldp;
548{
549	register long	result;
550	register int	tmy;
551
552	if (newp->tm_year < oldp->tm_year)
553		return -delta(oldp, newp);
554	result = 0;
555	for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy)
556		result += DAYSPERNYEAR + isleap_sum(tmy, TM_YEAR_BASE);
557	result += newp->tm_yday - oldp->tm_yday;
558	result *= HOURSPERDAY;
559	result += newp->tm_hour - oldp->tm_hour;
560	result *= MINSPERHOUR;
561	result += newp->tm_min - oldp->tm_min;
562	result *= SECSPERMIN;
563	result += newp->tm_sec - oldp->tm_sec;
564	return result;
565}
566
567static void
568show(char *zone, time_t t, int v)
569{
570	register struct tm *	tmp;
571
572	(void) printf("%-*s  ", (int) longest, zone);
573	if (v) {
574		tmp = gmtime(&t);
575		if (tmp == NULL) {
576			(void) printf(tformat(), t);
577		} else {
578			dumptime(tmp);
579			(void) printf(" UTC");
580		}
581		(void) printf(" = ");
582	}
583	tmp = my_localtime(&t);
584	dumptime(tmp);
585	if (tmp != NULL) {
586		if (*abbr(tmp) != '\0')
587			(void) printf(" %s", abbr(tmp));
588		if (v) {
589			(void) printf(" isdst=%d", tmp->tm_isdst);
590#ifdef TM_GMTOFF
591			(void) printf(" gmtoff=%ld", tmp->TM_GMTOFF);
592#endif /* defined TM_GMTOFF */
593		}
594	}
595	(void) printf("\n");
596	if (tmp != NULL && *abbr(tmp) != '\0')
597		abbrok(abbr(tmp), zone);
598}
599
600static const char *
601abbr(tmp)
602struct tm *	tmp;
603{
604	register const char *	result;
605	static const char	nada;
606
607	if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1)
608		return &nada;
609	result = tzname[tmp->tm_isdst];
610	return (result == NULL) ? &nada : result;
611}
612
613/*
614** The code below can fail on certain theoretical systems;
615** it works on all known real-world systems as of 2004-12-30.
616*/
617
618static const char *
619tformat(void)
620{
621	if (0.5 == (time_t) 0.5) {	/* floating */
622		if (sizeof (time_t) > sizeof (double))
623			return "%Lg";
624		return "%g";
625	}
626	if (0 > (time_t) -1) {		/* signed */
627		if (sizeof (time_t) > sizeof (long))
628			return "%lld";
629		if (sizeof (time_t) > sizeof (int))
630			return "%ld";
631		return "%d";
632	}
633	if (sizeof (time_t) > sizeof (unsigned long))
634		return "%llu";
635	if (sizeof (time_t) > sizeof (unsigned int))
636		return "%lu";
637	return "%u";
638}
639
640static void
641dumptime(timeptr)
642register const struct tm *	timeptr;
643{
644	static const char	wday_name[][3] = {
645		"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
646	};
647	static const char	mon_name[][3] = {
648		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
649		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
650	};
651	register const char *	wn;
652	register const char *	mn;
653	register int		lead;
654	register int		trail;
655
656	if (timeptr == NULL) {
657		(void) printf("NULL");
658		return;
659	}
660	/*
661	** The packaged versions of localtime and gmtime never put out-of-range
662	** values in tm_wday or tm_mon, but since this code might be compiled
663	** with other (perhaps experimental) versions, paranoia is in order.
664	*/
665	if (timeptr->tm_wday < 0 || timeptr->tm_wday >=
666		(int) (sizeof wday_name / sizeof wday_name[0]))
667			wn = "???";
668	else		wn = wday_name[timeptr->tm_wday];
669	if (timeptr->tm_mon < 0 || timeptr->tm_mon >=
670		(int) (sizeof mon_name / sizeof mon_name[0]))
671			mn = "???";
672	else		mn = mon_name[timeptr->tm_mon];
673	(void) printf("%.3s %.3s%3d %.2d:%.2d:%.2d ",
674		wn, mn,
675		timeptr->tm_mday, timeptr->tm_hour,
676		timeptr->tm_min, timeptr->tm_sec);
677#define DIVISOR	10
678	trail = timeptr->tm_year % DIVISOR + TM_YEAR_BASE % DIVISOR;
679	lead = timeptr->tm_year / DIVISOR + TM_YEAR_BASE / DIVISOR +
680		trail / DIVISOR;
681	trail %= DIVISOR;
682	if (trail < 0 && lead > 0) {
683		trail += DIVISOR;
684		--lead;
685	} else if (lead < 0 && trail > 0) {
686		trail -= DIVISOR;
687		++lead;
688	}
689	if (lead == 0)
690		(void) printf("%d", trail);
691	else	(void) printf("%d%d", lead, ((trail < 0) ? -trail : trail));
692}
693