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zdump.c revision 1.39
      1 /*	$NetBSD: zdump.c,v 1.39 2014/10/23 18:45:58 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 __RCSID("$NetBSD: zdump.c,v 1.39 2014/10/23 18:45:58 christos Exp $");
     10 #endif /* !defined lint */
     11 
     12 /*
     13 ** This code has been made independent of the rest of the time
     14 ** conversion package to increase confidence in the verification it provides.
     15 ** You can use this code to help in verifying other implementations.
     16 **
     17 ** To do this, compile with -DUSE_LTZ=0 and link without the tz library.
     18 */
     19 
     20 #ifndef NETBSD_INSPIRED
     21 # define NETBSD_INSPIRED 1
     22 #endif
     23 #ifndef USE_LTZ
     24 # define USE_LTZ 1
     25 #endif
     26 
     27 #if USE_LTZ
     28 #include "private.h"
     29 #endif
     30 
     31 /* Enable tm_gmtoff and tm_zone on GNUish systems.  */
     32 #define _GNU_SOURCE 1
     33 /* Enable strtoimax on Solaris 10.  */
     34 #define __EXTENSIONS__ 1
     35 
     36 #include "stdio.h"	/* for stdout, stderr */
     37 #include "string.h"	/* for strcpy */
     38 #include "sys/types.h"	/* for time_t */
     39 #include "time.h"	/* for struct tm */
     40 #include "stdlib.h"	/* for exit, malloc, atoi */
     41 #include "limits.h"	/* for CHAR_BIT, LLONG_MAX */
     42 #include <errno.h>
     43 #include <err.h>
     44 
     45 /*
     46 ** Substitutes for pre-C99 compilers.
     47 ** Much of this section of code is stolen from private.h.
     48 */
     49 
     50 #ifndef HAVE_STDINT_H
     51 # define HAVE_STDINT_H \
     52     (199901 <= __STDC_VERSION__ \
     53      || 2 < __GLIBC__ + (1 <= __GLIBC_MINOR__)	\
     54      || __CYGWIN__)
     55 #endif
     56 #if HAVE_STDINT_H
     57 # include "stdint.h"
     58 #endif
     59 #ifndef HAVE_INTTYPES_H
     60 # define HAVE_INTTYPES_H HAVE_STDINT_H
     61 #endif
     62 #if HAVE_INTTYPES_H
     63 # include <inttypes.h>
     64 #endif
     65 
     66 #ifndef INT_FAST32_MAX
     67 # if INT_MAX >> 31 == 0
     68 typedef long int_fast32_t;
     69 # else
     70 typedef int int_fast32_t;
     71 # endif
     72 #endif
     73 
     74 /* Pre-C99 GCC compilers define __LONG_LONG_MAX__ instead of LLONG_MAX.  */
     75 #if !defined LLONG_MAX && defined __LONG_LONG_MAX__
     76 # define LLONG_MAX __LONG_LONG_MAX__
     77 #endif
     78 
     79 #ifndef INTMAX_MAX
     80 # ifdef LLONG_MAX
     81 typedef long long intmax_t;
     82 #  define strtoimax strtoll
     83 #  define INTMAX_MAX LLONG_MAX
     84 # else
     85 typedef long intmax_t;
     86 #  define strtoimax strtol
     87 #  define INTMAX_MAX LONG_MAX
     88 # endif
     89 #endif
     90 
     91 #ifndef PRIdMAX
     92 # if INTMAX_MAX == LLONG_MAX
     93 #  define PRIdMAX "lld"
     94 # else
     95 #  define PRIdMAX "ld"
     96 # endif
     97 #endif
     98 
     99 /* Infer TM_ZONE on systems where this information is known, but suppress
    100    guessing if NO_TM_ZONE is defined.  Similarly for TM_GMTOFF.  */
    101 #if (defined __GLIBC__ \
    102      || defined __FreeBSD__ || defined __NetBSD__ || defined __OpenBSD__ \
    103      || (defined __APPLE__ && defined __MACH__))
    104 # if !defined TM_GMTOFF && !defined NO_TM_GMTOFF
    105 #  define TM_GMTOFF tm_gmtoff
    106 # endif
    107 # if !defined TM_ZONE && !defined NO_TM_ZONE
    108 #  define TM_ZONE tm_zone
    109 # endif
    110 #endif
    111 
    112 #ifndef HAVE_LOCALTIME_R
    113 # define HAVE_LOCALTIME_R 1
    114 #endif
    115 
    116 #ifndef HAVE_LOCALTIME_RZ
    117 # ifdef TM_ZONE
    118 #  define HAVE_LOCALTIME_RZ (NETBSD_INSPIRED && USE_LTZ)
    119 # else
    120 #  define HAVE_LOCALTIME_RZ 0
    121 # endif
    122 #endif
    123 
    124 #ifndef HAVE_TZSET
    125 # define HAVE_TZSET 1
    126 #endif
    127 
    128 #ifndef ZDUMP_LO_YEAR
    129 #define ZDUMP_LO_YEAR	(-500)
    130 #endif /* !defined ZDUMP_LO_YEAR */
    131 
    132 #ifndef ZDUMP_HI_YEAR
    133 #define ZDUMP_HI_YEAR	2500
    134 #endif /* !defined ZDUMP_HI_YEAR */
    135 
    136 #ifndef MAX_STRING_LENGTH
    137 #define MAX_STRING_LENGTH	1024
    138 #endif /* !defined MAX_STRING_LENGTH */
    139 
    140 #if __STDC_VERSION__ < 199901
    141 # define true 1
    142 # define false 0
    143 # define bool int
    144 #else
    145 # include <stdbool.h>
    146 #endif
    147 
    148 #ifndef EXIT_SUCCESS
    149 #define EXIT_SUCCESS	0
    150 #endif /* !defined EXIT_SUCCESS */
    151 
    152 #ifndef EXIT_FAILURE
    153 #define EXIT_FAILURE	1
    154 #endif /* !defined EXIT_FAILURE */
    155 
    156 #ifndef SECSPERMIN
    157 #define SECSPERMIN	60
    158 #endif /* !defined SECSPERMIN */
    159 
    160 #ifndef MINSPERHOUR
    161 #define MINSPERHOUR	60
    162 #endif /* !defined MINSPERHOUR */
    163 
    164 #ifndef SECSPERHOUR
    165 #define SECSPERHOUR	(SECSPERMIN * MINSPERHOUR)
    166 #endif /* !defined SECSPERHOUR */
    167 
    168 #ifndef HOURSPERDAY
    169 #define HOURSPERDAY	24
    170 #endif /* !defined HOURSPERDAY */
    171 
    172 #ifndef EPOCH_YEAR
    173 #define EPOCH_YEAR	1970
    174 #endif /* !defined EPOCH_YEAR */
    175 
    176 #ifndef TM_YEAR_BASE
    177 #define TM_YEAR_BASE	1900
    178 #endif /* !defined TM_YEAR_BASE */
    179 
    180 #ifndef DAYSPERNYEAR
    181 #define DAYSPERNYEAR	365
    182 #endif /* !defined DAYSPERNYEAR */
    183 
    184 #ifndef isleap
    185 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
    186 #endif /* !defined isleap */
    187 
    188 #ifndef isleap_sum
    189 /*
    190 ** See tzfile.h for details on isleap_sum.
    191 */
    192 #define isleap_sum(a, b)	isleap((a) % 400 + (b) % 400)
    193 #endif /* !defined isleap_sum */
    194 
    195 #define SECSPERDAY	((int_fast32_t) SECSPERHOUR * HOURSPERDAY)
    196 #define SECSPERNYEAR	(SECSPERDAY * DAYSPERNYEAR)
    197 #define SECSPERLYEAR	(SECSPERNYEAR + SECSPERDAY)
    198 #define SECSPER400YEARS	(SECSPERNYEAR * (intmax_t) (300 + 3)	\
    199 			 + SECSPERLYEAR * (intmax_t) (100 - 3))
    200 
    201 /*
    202 ** True if SECSPER400YEARS is known to be representable as an
    203 ** intmax_t.  It's OK that SECSPER400YEARS_FITS can in theory be false
    204 ** even if SECSPER400YEARS is representable, because when that happens
    205 ** the code merely runs a bit more slowly, and this slowness doesn't
    206 ** occur on any practical platform.
    207 */
    208 enum { SECSPER400YEARS_FITS = SECSPERLYEAR <= INTMAX_MAX / 400 };
    209 
    210 #ifndef HAVE_GETTEXT
    211 #define HAVE_GETTEXT 0
    212 #endif
    213 #if HAVE_GETTEXT
    214 #include "locale.h"	/* for setlocale */
    215 #include "libintl.h"
    216 #endif /* HAVE_GETTEXT */
    217 
    218 #ifndef ATTRIBUTE_PURE
    219 #if 2 < __GNUC__ || (__GNUC__ == 2 && 96 <= __GNUC_MINOR__)
    220 # define ATTRIBUTE_PURE __attribute__ ((ATTRIBUTE_PURE__))
    221 #else
    222 # define ATTRIBUTE_PURE /* empty */
    223 #endif
    224 #endif
    225 
    226 #ifndef INITIALIZE
    227 #if defined(__GNUC__) || defined(__lint__)
    228 #define INITIALIZE(x)	((x) = 0)
    229 #else /* !defined GNUC || lint */
    230 #define INITIALIZE(x)
    231 #endif /* !defined GNUC || lint */
    232 #endif /* !defined INITIALIZE */
    233 
    234 /*
    235 ** For the benefit of GNU folk...
    236 ** '_(MSGID)' uses the current locale's message library string for MSGID.
    237 ** The default is to use gettext if available, and use MSGID otherwise.
    238 */
    239 
    240 #ifndef _
    241 #if HAVE_GETTEXT
    242 #define _(msgid) gettext(msgid)
    243 #else /* !HAVE_GETTEXT */
    244 #define _(msgid) msgid
    245 #endif /* !HAVE_GETTEXT */
    246 #endif /* !defined _ */
    247 
    248 #if !defined TZ_DOMAIN && defined HAVE_GETTEXT
    249 # define TZ_DOMAIN "tz"
    250 #endif
    251 
    252 #if ! HAVE_LOCALTIME_RZ
    253 # undef  timezone_t
    254 # define timezone_t char **
    255 #endif
    256 
    257 extern char **	environ;
    258 extern int	getopt(int argc, char * const argv[],
    259 			const char * options);
    260 extern char *	optarg;
    261 extern int	optind;
    262 
    263 /* The minimum and maximum finite time values.  */
    264 static time_t	absolute_min_time =
    265   ((time_t) -1 < 0
    266     ? (time_t) -1 << (CHAR_BIT * sizeof (time_t) - 1)
    267     : 0);
    268 static time_t	absolute_max_time =
    269   ((time_t) -1 < 0
    270     ? - (~ 0 < 0) - ((time_t) -1 << (CHAR_BIT * sizeof (time_t) - 1))
    271    : -1);
    272 static size_t	longest;
    273 static char *	progname;
    274 static bool	warned;
    275 static bool	errout;
    276 
    277 static char const *abbr(struct tm const *);
    278 static intmax_t	delta(struct tm *, struct tm *) ATTRIBUTE_PURE;
    279 static void dumptime(struct tm const *);
    280 static time_t hunt(timezone_t, char *, time_t, time_t);
    281 static void show(timezone_t, char *, time_t, bool);
    282 static const char *tformat(void);
    283 static time_t yeartot(intmax_t) ATTRIBUTE_PURE;
    284 
    285 /* Is A an alphabetic character in the C locale?  */
    286 static bool
    287 is_alpha(char a)
    288 {
    289 	switch (a) {
    290 	  default:
    291 		return false;
    292 	  case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': case 'G':
    293 	  case 'H': case 'I': case 'J': case 'K': case 'L': case 'M': case 'N':
    294 	  case 'O': case 'P': case 'Q': case 'R': case 'S': case 'T': case 'U':
    295 	  case 'V': case 'W': case 'X': case 'Y': case 'Z':
    296 	  case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': case 'g':
    297 	  case 'h': case 'i': case 'j': case 'k': case 'l': case 'm': case 'n':
    298 	  case 'o': case 'p': case 'q': case 'r': case 's': case 't': case 'u':
    299 	  case 'v': case 'w': case 'x': case 'y': case 'z':
    300 	  	return true;
    301 	}
    302 }
    303 
    304 /* Return A + B, exiting if the result would overflow.  */
    305 static size_t
    306 sumsize(size_t a, size_t b)
    307 {
    308 	size_t sum = a + b;
    309 	if (sum < a)
    310 		errx(EXIT_FAILURE, "size overflow");
    311 	return sum;
    312 }
    313 
    314 #if ! HAVE_TZSET
    315 # undef tzset
    316 # define tzset zdump_tzset
    317 static void tzset(void) { }
    318 #endif
    319 
    320 /* Assume gmtime_r works if localtime_r does.
    321    A replacement localtime_r is defined below if needed.  */
    322 #if ! HAVE_LOCALTIME_R
    323 
    324 # undef gmtime_r
    325 # define gmtime_r zdump_gmtime_r
    326 
    327 static struct tm *
    328 gmtime_r(time_t *tp, struct tm *tmp)
    329 {
    330 	struct tm *r = gmtime(tp);
    331 	if (r) {
    332 		*tmp = *r;
    333 		r = tmp;
    334 	}
    335 	return r;
    336 }
    337 
    338 #endif
    339 
    340 /* Platforms with TM_ZONE don't need tzname, so they can use the
    341    faster localtime_rz or localtime_r if available.  */
    342 
    343 #if defined TM_ZONE && HAVE_LOCALTIME_RZ
    344 # define USE_LOCALTIME_RZ true
    345 #else
    346 # define USE_LOCALTIME_RZ false
    347 #endif
    348 
    349 #if ! USE_LOCALTIME_RZ
    350 
    351 # if !defined TM_ZONE || ! HAVE_LOCALTIME_R || ! HAVE_TZSET
    352 #  undef localtime_r
    353 #  define localtime_r zdump_localtime_r
    354 static struct tm *
    355 localtime_r(time_t *tp, struct tm *tmp)
    356 {
    357 	struct tm *r = localtime(tp);
    358 	if (r) {
    359 		*tmp = *r;
    360 		r = tmp;
    361 	}
    362 	return r;
    363 }
    364 # endif
    365 
    366 # undef localtime_rz
    367 # define localtime_rz zdump_localtime_rz
    368 static struct tm *
    369 localtime_rz(timezone_t rz, time_t *tp, struct tm *tmp)
    370 {
    371 	return localtime_r(tp, tmp);
    372 }
    373 
    374 # ifdef TYPECHECK
    375 #  undef mktime_z
    376 #  define mktime_z zdump_mktime_z
    377 static time_t
    378 mktime_z(timezone_t tz, struct tm *tmp)
    379 {
    380 	return mktime(tmp);
    381 }
    382 # endif
    383 
    384 # undef tzalloc
    385 # undef tzfree
    386 # define tzalloc zdump_tzalloc
    387 # define tzfree zdump_tzfree
    388 
    389 static timezone_t
    390 tzalloc(char const *val)
    391 {
    392 	static char **fakeenv;
    393 	char **env = fakeenv;
    394 	char *env0;
    395 	if (! env) {
    396 		char **e = environ;
    397 		int to;
    398 
    399 		while (*e++)
    400 			continue;
    401 		env = malloc(sumsize(sizeof *environ,
    402 		    (e - environ) * sizeof *environ));
    403 		if (! env) {
    404 			err(EXIT_FAILURE, "malloc");
    405 		}
    406 		to = 1;
    407 		for (e = environ; (env[to] = *e); e++)
    408 			to += strncmp(*e, "TZ=", 3) != 0;
    409 	}
    410 	env0 = malloc(sumsize(sizeof "TZ=", strlen(val)));
    411 	if (! env0) {
    412 		err(EXIT_FAILURE, "malloc");
    413 	}
    414 	env[0] = strcat(strcpy(env0, "TZ="), val);
    415 	environ = fakeenv = env;
    416 	tzset();
    417 	return env;
    418 }
    419 
    420 static void
    421 tzfree(timezone_t env)
    422 {
    423 	environ = env + 1;
    424 	free(env[0]);
    425 }
    426 #endif /* ! USE_LOCALTIME_RZ */
    427 
    428 /* A UTC time zone, and its initializer.  */
    429 static timezone_t gmtz;
    430 static void
    431 gmtzinit(void)
    432 {
    433 	if (USE_LOCALTIME_RZ) {
    434 		static char const utc[] = "UTC0";
    435 		gmtz = tzalloc(utc);
    436 		if (!gmtz) {
    437 		      err(EXIT_FAILURE, "Cannot create %s", utc);
    438 		}
    439 	}
    440 }
    441 
    442 /* Convert *TP to UTC, storing the broken-down time into *TMP.
    443    Return TMP if successful, NULL otherwise.  This is like gmtime_r(TP, TMP),
    444    except typically faster if USE_LOCALTIME_RZ.  */
    445 static struct tm *
    446 my_gmtime_r(time_t *tp, struct tm *tmp)
    447 {
    448 	return USE_LOCALTIME_RZ ?
    449 	    localtime_rz(gmtz, tp, tmp) : gmtime_r(tp, tmp);
    450 }
    451 
    452 #ifndef TYPECHECK
    453 #define my_localtime_rz	localtime_rz
    454 #else /* !defined TYPECHECK */
    455 static struct tm *
    456 my_localtime_rz(timezone_t tz, const time_t *tp, struct tm *tmp)
    457 {
    458 	tmp = localtime_rz(tz, tp, tmp);
    459 	if (tmp) {
    460 		struct tm	tm;
    461 		time_t	t;
    462 
    463 		tm = *tmp;
    464 		t = mktime_z(tz, &tm);
    465 		if (t != *tp) {
    466 			(void) fflush(stdout);
    467 			(void) fprintf(stderr, "\n%s: ", progname);
    468 			(void) fprintf(stderr, tformat(), *tp);
    469 			(void) fprintf(stderr, " ->");
    470 			(void) fprintf(stderr, " year=%d", tmp->tm_year);
    471 			(void) fprintf(stderr, " mon=%d", tmp->tm_mon);
    472 			(void) fprintf(stderr, " mday=%d", tmp->tm_mday);
    473 			(void) fprintf(stderr, " hour=%d", tmp->tm_hour);
    474 			(void) fprintf(stderr, " min=%d", tmp->tm_min);
    475 			(void) fprintf(stderr, " sec=%d", tmp->tm_sec);
    476 			(void) fprintf(stderr, " isdst=%d", tmp->tm_isdst);
    477 			(void) fprintf(stderr, " -> ");
    478 			(void) fprintf(stderr, tformat(), t);
    479 			(void) fprintf(stderr, "\n");
    480 			errout = true;
    481 		}
    482 	}
    483 	return tmp;
    484 }
    485 #endif /* !defined TYPECHECK */
    486 
    487 static void
    488 abbrok(const char *const abbrp, const char *const zone)
    489 {
    490 	const char *cp;
    491 	const char *wp;
    492 
    493 	if (warned)
    494 		return;
    495 	cp = abbrp;
    496 	wp = NULL;
    497 	while (is_alpha(*cp))
    498 		++cp;
    499 	if (cp - abbrp == 0)
    500 		wp = _("lacks alphabetic at start");
    501 	else if (cp - abbrp < 3)
    502 		wp = _("has fewer than 3 alphabetics");
    503 	else if (cp - abbrp > 6)
    504 		wp = _("has more than 6 alphabetics");
    505 	if (wp == NULL && (*cp == '+' || *cp == '-')) {
    506 		++cp;
    507 		if ('0' <= *cp && *cp <= '9')
    508 			if (*cp++ == '1' && '0' <= *cp && *cp <= '4')
    509 				cp++;
    510 		if (*cp != '\0')
    511 			wp = _("differs from POSIX standard");
    512 	}
    513 	if (wp == NULL)
    514 		return;
    515 	(void) fflush(stdout);
    516 	(void) fprintf(stderr,
    517 		_("%s: warning: zone \"%s\" abbreviation \"%s\" %s\n"),
    518 		progname, zone, abbrp, wp);
    519 	warned = errout = true;
    520 }
    521 
    522 /* Return a time zone abbreviation.  If the abbreviation needs to be
    523    saved, use *BUF (of size *BUFALLOC) to save it, and return the
    524    abbreviation in the possibly-reallocated *BUF.  Otherwise, just
    525    return the abbreviation.  Get the abbreviation from TMP.
    526    Exit on memory allocation failure.  */
    527 static char const *
    528 saveabbr(char **buf, size_t *bufalloc, struct tm const *tmp)
    529 {
    530 	char const *ab = abbr(tmp);
    531 	if (HAVE_LOCALTIME_RZ)
    532 		return ab;
    533 	else {
    534 		size_t ablen = strlen(ab);
    535 		if (*bufalloc <= ablen) {
    536 			free(*buf);
    537 
    538 			/* Make the new buffer at least twice as long as the
    539 			   old, to avoid O(N**2) behavior on repeated calls.  */
    540 			*bufalloc = sumsize(*bufalloc, ablen + 1);
    541 			*buf = malloc(*bufalloc);
    542 			if (! *buf) {
    543 				err(EXIT_FAILURE, "malloc");
    544 			}
    545 		}
    546 		return strcpy(*buf, ab);
    547 	}
    548 }
    549 
    550 static void
    551 close_file(FILE *stream)
    552 {
    553 	char const *e = (ferror(stream) ? _("I/O error")
    554 	    : fclose(stream) != 0 ? strerror(errno) : NULL);
    555 	if (e) {
    556 		errx(EXIT_FAILURE, "%s", e);
    557 	}
    558 }
    559 
    560 __dead static void
    561 usage(FILE *const stream, const int status)
    562 {
    563 	(void) fprintf(stream,
    564 _("%s: usage: %s [--version] [--help] [-{vV}] [-{ct} [lo,]hi] zonename ...\n"
    565   "\n"
    566   "Report bugs to %s.\n"),
    567 		       progname, progname, REPORT_BUGS_TO);
    568 	if (status == EXIT_SUCCESS)
    569 		close_file(stream);
    570 	exit(status);
    571 }
    572 
    573 int
    574 main(int argc, char *argv[])
    575 {
    576 	/* These are static so that they're initially zero.  */
    577 	static char *		abbrev;
    578 	static size_t		abbrevsize;
    579 	static struct tm	newtm;
    580 
    581 	int		i;
    582 	bool		vflag;
    583 	bool		Vflag;
    584 	char *		cutarg;
    585 	char *		cuttimes;
    586 	time_t		cutlotime;
    587 	time_t		cuthitime;
    588 	time_t		now;
    589 	time_t		t;
    590 	time_t		newt;
    591 	struct tm	tm;
    592 	struct tm *	tmp;
    593 	struct tm *	newtmp;
    594 
    595 	cutlotime = absolute_min_time;
    596 	cuthitime = absolute_max_time;
    597 #if HAVE_GETTEXT
    598 	(void) setlocale(LC_ALL, "");
    599 #ifdef TZ_DOMAINDIR
    600 	(void) bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR);
    601 #endif /* defined TEXTDOMAINDIR */
    602 	(void) textdomain(TZ_DOMAIN);
    603 #endif /* HAVE_GETTEXT */
    604 	progname = argv[0];
    605 	for (i = 1; i < argc; ++i)
    606 		if (strcmp(argv[i], "--version") == 0) {
    607 			(void) printf("zdump %s%s\n", PKGVERSION, TZVERSION);
    608 			return EXIT_SUCCESS;
    609 		} else if (strcmp(argv[i], "--help") == 0) {
    610 			usage(stdout, EXIT_SUCCESS);
    611 		}
    612 	vflag = Vflag = false;
    613 	cutarg = cuttimes = NULL;
    614 	for (;;)
    615 	  switch (getopt(argc, argv, "c:t:vV")) {
    616 	  case 'c': cutarg = optarg; break;
    617 	  case 't': cuttimes = optarg; break;
    618 	  case 'v': vflag = true; break;
    619 	  case 'V': Vflag = true; break;
    620 	  case -1:
    621 	    if (! (optind == argc - 1 && strcmp(argv[optind], "=") == 0))
    622 	      goto arg_processing_done;
    623 	    /* Fall through.  */
    624 	  default:
    625 	    usage(stderr, EXIT_FAILURE);
    626 	  }
    627  arg_processing_done:;
    628 
    629 	if (vflag | Vflag) {
    630 		intmax_t	lo;
    631 		intmax_t	hi;
    632 		char *loend, *hiend;
    633 		intmax_t cutloyear = ZDUMP_LO_YEAR;
    634 		intmax_t cuthiyear = ZDUMP_HI_YEAR;
    635 		if (cutarg != NULL) {
    636 			lo = strtoimax(cutarg, &loend, 10);
    637 			if (cutarg != loend && !*loend) {
    638 				hi = lo;
    639 				cuthiyear = hi;
    640 			} else if (cutarg != loend && *loend == ','
    641 				   && (hi = strtoimax(loend + 1, &hiend, 10),
    642 				       loend + 1 != hiend && !*hiend)) {
    643 				cutloyear = lo;
    644 				cuthiyear = hi;
    645 			} else {
    646 				fprintf(stderr, _("%s: wild -c argument %s\n"),
    647 					progname, cutarg);
    648 				return EXIT_FAILURE;
    649 			}
    650 		}
    651 		if (cutarg != NULL || cuttimes == NULL) {
    652 			cutlotime = yeartot(cutloyear);
    653 			cuthitime = yeartot(cuthiyear);
    654 		}
    655 		if (cuttimes != NULL) {
    656 			lo = strtoimax(cuttimes, &loend, 10);
    657 			if (cuttimes != loend && !*loend) {
    658 				hi = lo;
    659 				if (hi < cuthitime) {
    660 					if (hi < absolute_min_time)
    661 						hi = absolute_min_time;
    662 					cuthitime = hi;
    663 				}
    664 			} else if (cuttimes != loend && *loend == ','
    665 				   && (hi = strtoimax(loend + 1, &hiend, 10),
    666 				       loend + 1 != hiend && !*hiend)) {
    667 				if (cutlotime < lo) {
    668 					if (absolute_max_time < lo)
    669 						lo = absolute_max_time;
    670 					cutlotime = lo;
    671 				}
    672 				if (hi < cuthitime) {
    673 					if (hi < absolute_min_time)
    674 						hi = absolute_min_time;
    675 					cuthitime = hi;
    676 				}
    677 			} else {
    678 				(void) fprintf(stderr,
    679 					_("%s: wild -t argument %s\n"),
    680 					progname, cuttimes);
    681 				return EXIT_FAILURE;
    682 			}
    683 		}
    684 	}
    685 	gmtzinit();
    686 	now = time(NULL);
    687 	longest = 0;
    688 	for (i = optind; i < argc; i++) {
    689 		size_t arglen = strlen(argv[i]);
    690 		if (longest < arglen)
    691 			longest = arglen < INT_MAX ? arglen : INT_MAX;
    692 	}
    693 
    694 	for (i = optind; i < argc; ++i) {
    695 		timezone_t tz = tzalloc(argv[i]);
    696 		char const *ab;
    697 		if (!tz) {
    698 			errx(EXIT_FAILURE, "%s", argv[i]);
    699 		}
    700 		if (! (vflag | Vflag)) {
    701 			show(tz, argv[i], now, false);
    702 			tzfree(tz);
    703 			continue;
    704 		}
    705 		warned = false;
    706 		t = absolute_min_time;
    707 		if (!Vflag) {
    708 			show(tz, argv[i], t, true);
    709 			t += SECSPERDAY;
    710 			show(tz, argv[i], t, true);
    711 		}
    712 		if (t < cutlotime)
    713 			t = cutlotime;
    714 		tmp = my_localtime_rz(tz, &t, &tm);
    715 		if (tmp)
    716 			ab = saveabbr(&abbrev, &abbrevsize, &tm);
    717 		else
    718 			ab = NULL;
    719 		while (t < cuthitime) {
    720 			newt = ((t < absolute_max_time - SECSPERDAY / 2
    721 				&& t + SECSPERDAY / 2 < cuthitime)
    722 				? t + SECSPERDAY / 2
    723 				: cuthitime);
    724 			newtmp = localtime_rz(tz, &newt, &newtm);
    725 			if ((tmp == NULL || newtmp == NULL) ? (tmp != newtmp) :
    726 			    (delta(&newtm, &tm) != (newt - t) ||
    727 			    newtm.tm_isdst != tm.tm_isdst ||
    728 			    strcmp(abbr(&newtm), ab) != 0)) {
    729 				newt = hunt(tz, argv[i], t, newt);
    730 				newtmp = localtime_rz(tz, &newt, &newtm);
    731 				if (newtmp)
    732 					  ab = saveabbr(&abbrev, &abbrevsize,
    733 							&newtm);
    734 			}
    735 			t = newt;
    736 			tm = newtm;
    737 			tmp = newtmp;
    738 		}
    739 		if (!Vflag) {
    740 			t = absolute_max_time;
    741 			t -= SECSPERDAY;
    742 			show(tz, argv[i], t, true);
    743 			t += SECSPERDAY;
    744 			show(tz, argv[i], t, true);
    745 		}
    746 		tzfree(tz);
    747 	}
    748 	close_file(stdout);
    749 	if (errout && (ferror(stderr) || fclose(stderr) != 0))
    750 		return EXIT_FAILURE;
    751 	return EXIT_SUCCESS;
    752 }
    753 
    754 static time_t
    755 yeartot(const intmax_t y)
    756 {
    757 	intmax_t	myy, seconds, years;
    758 	time_t		t;
    759 
    760 	myy = EPOCH_YEAR;
    761 	t = 0;
    762 	while (myy < y) {
    763 		if (SECSPER400YEARS_FITS && 400 <= y - myy) {
    764 			intmax_t diff400 = (y - myy) / 400;
    765 			if (INTMAX_MAX / SECSPER400YEARS < diff400)
    766 				return absolute_max_time;
    767 			seconds = diff400 * SECSPER400YEARS;
    768 			years = diff400 * 400;
    769                 } else {
    770 			seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
    771 			years = 1;
    772 		}
    773 		myy += years;
    774 		if (t > absolute_max_time - seconds)
    775 			return absolute_max_time;
    776 		t += seconds;
    777 	}
    778 	while (y < myy) {
    779 		if (SECSPER400YEARS_FITS && y + 400 <= myy && myy < 0) {
    780 			intmax_t diff400 = (myy - y) / 400;
    781 			if (INTMAX_MAX / SECSPER400YEARS < diff400)
    782 				return absolute_min_time;
    783 			seconds = diff400 * SECSPER400YEARS;
    784 			years = diff400 * 400;
    785 		} else {
    786 			seconds = isleap(myy - 1) ? SECSPERLYEAR : SECSPERNYEAR;
    787 			years = 1;
    788 		}
    789 		myy -= years;
    790 		if (t < absolute_min_time + seconds)
    791 			return absolute_min_time;
    792 		t -= seconds;
    793 	}
    794 	return t;
    795 }
    796 
    797 static time_t
    798 hunt(timezone_t tz, char *name, time_t lot, time_t hit)
    799 {
    800 	static char *		loab;
    801 	static size_t		loabsize;
    802 	char const *		ab;
    803 	time_t			t;
    804 	struct tm		lotm;
    805 	struct tm *	lotmp;
    806 	struct tm		tm;
    807 	struct tm *	tmp;
    808 
    809 	lotmp = my_localtime_rz(tz, &lot, &lotm);
    810 	if (lotmp)
    811 		ab = saveabbr(&loab, &loabsize, &lotm);
    812 	else
    813 		ab = NULL;
    814 	for ( ; ; ) {
    815 		time_t diff = hit - lot;
    816 		if (diff < 2)
    817 			break;
    818 		t = lot;
    819 		t += diff / 2;
    820 		if (t <= lot)
    821 			++t;
    822 		else if (t >= hit)
    823 			--t;
    824 		tmp = my_localtime_rz(tz, &t, &tm);
    825 		if ((lotmp == NULL || tmp == NULL) ? (lotmp == tmp) :
    826 			(delta(&tm, &lotm) == (t - lot) &&
    827 			tm.tm_isdst == lotm.tm_isdst &&
    828 			strcmp(abbr(&tm), ab) == 0)) {
    829 				lot = t;
    830 				lotm = tm;
    831 				lotmp = tmp;
    832 		} else	hit = t;
    833 	}
    834 	show(tz, name, lot, true);
    835 	show(tz, name, hit, true);
    836 	return hit;
    837 }
    838 
    839 /*
    840 ** Thanks to Paul Eggert for logic used in delta.
    841 */
    842 
    843 static intmax_t
    844 delta(struct tm *newp, struct tm *oldp)
    845 {
    846 	intmax_t	result;
    847 	int		tmy;
    848 
    849 	if (newp->tm_year < oldp->tm_year)
    850 		return -delta(oldp, newp);
    851 	result = 0;
    852 	for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy)
    853 		result += DAYSPERNYEAR + isleap_sum(tmy, TM_YEAR_BASE);
    854 	result += newp->tm_yday - oldp->tm_yday;
    855 	result *= HOURSPERDAY;
    856 	result += newp->tm_hour - oldp->tm_hour;
    857 	result *= MINSPERHOUR;
    858 	result += newp->tm_min - oldp->tm_min;
    859 	result *= SECSPERMIN;
    860 	result += newp->tm_sec - oldp->tm_sec;
    861 	return result;
    862 }
    863 #endif
    864 
    865 #ifndef TM_GMTOFF
    866 /* Return A->tm_yday, adjusted to compare it fairly to B->tm_yday.
    867    Assume A and B differ by at most one year.  */
    868 static int
    869 adjusted_yday(struct tm const *a, struct tm const *b)
    870 {
    871 	int yday = a->tm_yday;
    872 	if (b->tm_year < a->tm_year)
    873 		yday += 365 + isleap_sum(b->tm_year, TM_YEAR_BASE);
    874 	return yday;
    875 }
    876 #endif
    877 
    878 /* If A is the broken-down local time and B the broken-down UTC for
    879    the same instant, return A's UTC offset in seconds, where positive
    880    offsets are east of Greenwich.  On failure, return LONG_MIN.  */
    881 static long
    882 gmtoff(struct tm const *a, struct tm const *b)
    883 {
    884 #ifdef TM_GMTOFF
    885 	return a->TM_GMTOFF;
    886 #else
    887 	if (! b)
    888 		return LONG_MIN;
    889 	else {
    890 		int ayday = adjusted_yday(a, b);
    891 		int byday = adjusted_yday(b, a);
    892 		int days = ayday - byday;
    893 		long hours = a->tm_hour - b->tm_hour + 24 * days;
    894 		long minutes = a->tm_min - b->tm_min + 60 * hours;
    895 		long seconds = a->tm_sec - b->tm_sec + 60 * minutes;
    896 		return seconds;
    897 	}
    898 #endif
    899 }
    900 
    901 static void
    902 show(timezone_t tz, char *zone, time_t t, bool v)
    903 {
    904 	struct tm *	tmp;
    905 	struct tm *	gmtmp;
    906 	struct tm tm, gmtm;
    907 
    908 	(void) printf("%-*s  ", (int) longest, zone);
    909 	if (v) {
    910 		gmtmp = my_gmtime_r(&t, &gmtm);
    911 		if (gmtmp == NULL) {
    912 			printf(tformat(), t);
    913 		} else {
    914 			dumptime(gmtmp);
    915 			(void) printf(" UT");
    916 		}
    917 		(void) printf(" = ");
    918 	}
    919 	tmp = my_localtime_rz(tz, &t, &tm);
    920 	dumptime(tmp);
    921 	if (tmp != NULL) {
    922 		if (*abbr(tmp) != '\0')
    923 			(void) printf(" %s", abbr(tmp));
    924 		if (v) {
    925 			long off = gmtoff(tmp, gmtmp);
    926 			(void) printf(" isdst=%d", tmp->tm_isdst);
    927 			if (off != LONG_MIN)
    928 				(void) printf(" gmtoff=%ld", off);
    929 		}
    930 	}
    931 	(void) printf("\n");
    932 	if (tmp != NULL && *abbr(tmp) != '\0')
    933 		abbrok(abbr(tmp), zone);
    934 }
    935 
    936 static const char *
    937 abbr(struct tm const *tmp)
    938 {
    939 #ifdef TM_ZONE
    940 	return tmp->TM_ZONE;
    941 #else
    942 	return (0 <= tmp->tm_isdst && tzname[0 < tmp->tm_isdst]
    943 		? tzname[0 < tmp->tm_isdst]
    944 		: "");
    945 #endif
    946 }
    947 
    948 /*
    949 ** The code below can fail on certain theoretical systems;
    950 ** it works on all known real-world systems as of 2004-12-30.
    951 */
    952 
    953 static const char *
    954 tformat(void)
    955 {
    956 	if (0 > (time_t) -1) {		/* signed */
    957 		if (sizeof (time_t) == sizeof (intmax_t))
    958 			return "%"PRIdMAX;
    959 		if (sizeof (time_t) > sizeof (long))
    960 			return "%lld";
    961 		if (sizeof (time_t) > sizeof (int))
    962 			return "%ld";
    963 		return "%d";
    964 	}
    965 #ifdef PRIuMAX
    966 	if (sizeof (time_t) == sizeof (uintmax_t))
    967 		return "%"PRIuMAX;
    968 #endif
    969 	if (sizeof (time_t) > sizeof (unsigned long))
    970 		return "%llu";
    971 	if (sizeof (time_t) > sizeof (unsigned int))
    972 		return "%lu";
    973 	return "%u";
    974 }
    975 
    976 static void
    977 dumptime(const struct tm *timeptr)
    978 {
    979 	static const char	wday_name[][3] = {
    980 		"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
    981 	};
    982 	static const char	mon_name[][3] = {
    983 		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
    984 		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
    985 	};
    986 	const char *	wn;
    987 	const char *	mn;
    988 	int		lead;
    989 	int		trail;
    990 
    991 	if (timeptr == NULL) {
    992 		printf("NULL");
    993 		return;
    994 	}
    995 	/*
    996 	** The packaged localtime_rz and gmtime_r never put out-of-range
    997 	** values in tm_wday or tm_mon, but since this code might be compiled
    998 	** with other (perhaps experimental) versions, paranoia is in order.
    999 	*/
   1000 	if (timeptr->tm_wday < 0 || timeptr->tm_wday >=
   1001 		(int) (sizeof wday_name / sizeof wday_name[0]))
   1002 			wn = "???";
   1003 	else		wn = wday_name[timeptr->tm_wday];
   1004 	if (timeptr->tm_mon < 0 || timeptr->tm_mon >=
   1005 		(int) (sizeof mon_name / sizeof mon_name[0]))
   1006 			mn = "???";
   1007 	else		mn = mon_name[timeptr->tm_mon];
   1008 	printf("%.3s %.3s%3d %.2d:%.2d:%.2d ",
   1009 		wn, mn,
   1010 		timeptr->tm_mday, timeptr->tm_hour,
   1011 		timeptr->tm_min, timeptr->tm_sec);
   1012 #define DIVISOR	10
   1013 	trail = timeptr->tm_year % DIVISOR + TM_YEAR_BASE % DIVISOR;
   1014 	lead = timeptr->tm_year / DIVISOR + TM_YEAR_BASE / DIVISOR +
   1015 		trail / DIVISOR;
   1016 	trail %= DIVISOR;
   1017 	if (trail < 0 && lead > 0) {
   1018 		trail += DIVISOR;
   1019 		--lead;
   1020 	} else if (lead < 0 && trail > 0) {
   1021 		trail -= DIVISOR;
   1022 		++lead;
   1023 	}
   1024 	if (lead == 0)
   1025 		printf("%d", trail);
   1026 	else	printf("%d%d", lead, ((trail < 0) ? -trail : trail));
   1027 }
   1028