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-rw-r--r--REORG.TODO/timezone/zdump.c1012
1 files changed, 1012 insertions, 0 deletions
diff --git a/REORG.TODO/timezone/zdump.c b/REORG.TODO/timezone/zdump.c
new file mode 100644
index 0000000000..063a2635ec
--- /dev/null
+++ b/REORG.TODO/timezone/zdump.c
@@ -0,0 +1,1012 @@
+/*
+** This file is in the public domain, so clarified as of
+** 2009-05-17 by Arthur David Olson.
+*/
+
+#include "version.h"
+
+/*
+** 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.
+** To do this, compile with -DUSE_LTZ=0 and link without the tz library.
+*/
+
+#ifndef NETBSD_INSPIRED
+# define NETBSD_INSPIRED 1
+#endif
+#ifndef USE_LTZ
+# define USE_LTZ 1
+#endif
+
+#if USE_LTZ
+# include "private.h"
+#endif
+
+/* Enable tm_gmtoff and tm_zone on GNUish systems.  */
+#define _GNU_SOURCE 1
+/* Enable strtoimax on Solaris 10.  */
+#define __EXTENSIONS__ 1
+
+#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 "limits.h"	/* for CHAR_BIT, LLONG_MAX */
+#include <errno.h>
+
+/*
+** Substitutes for pre-C99 compilers.
+** Much of this section of code is stolen from private.h.
+*/
+
+#ifndef HAVE_STDINT_H
+# define HAVE_STDINT_H \
+    (199901 <= __STDC_VERSION__ \
+     || 2 < __GLIBC__ + (1 <= __GLIBC_MINOR__)	\
+     || __CYGWIN__)
+#endif
+#if HAVE_STDINT_H
+# include "stdint.h"
+#endif
+#ifndef HAVE_INTTYPES_H
+# define HAVE_INTTYPES_H HAVE_STDINT_H
+#endif
+#if HAVE_INTTYPES_H
+# include <inttypes.h>
+#endif
+
+#ifndef INT_FAST32_MAX
+# if INT_MAX >> 31 == 0
+typedef long int_fast32_t;
+# else
+typedef int int_fast32_t;
+# endif
+#endif
+
+/* Pre-C99 GCC compilers define __LONG_LONG_MAX__ instead of LLONG_MAX.  */
+#if !defined LLONG_MAX && defined __LONG_LONG_MAX__
+# define LLONG_MAX __LONG_LONG_MAX__
+#endif
+
+#ifndef INTMAX_MAX
+# ifdef LLONG_MAX
+typedef long long intmax_t;
+#  define strtoimax strtoll
+#  define INTMAX_MAX LLONG_MAX
+# else
+typedef long intmax_t;
+#  define strtoimax strtol
+#  define INTMAX_MAX LONG_MAX
+# endif
+#endif
+
+#ifndef PRIdMAX
+# if INTMAX_MAX == LLONG_MAX
+#  define PRIdMAX "lld"
+# else
+#  define PRIdMAX "ld"
+# endif
+#endif
+
+/* Infer TM_ZONE on systems where this information is known, but suppress
+   guessing if NO_TM_ZONE is defined.  Similarly for TM_GMTOFF.  */
+#if (defined __GLIBC__ \
+     || defined __FreeBSD__ || defined __NetBSD__ || defined __OpenBSD__ \
+     || (defined __APPLE__ && defined __MACH__))
+# if !defined TM_GMTOFF && !defined NO_TM_GMTOFF
+#  define TM_GMTOFF tm_gmtoff
+# endif
+# if !defined TM_ZONE && !defined NO_TM_ZONE
+#  define TM_ZONE tm_zone
+# endif
+#endif
+
+#ifndef HAVE_LOCALTIME_R
+# define HAVE_LOCALTIME_R 1
+#endif
+
+#ifndef HAVE_LOCALTIME_RZ
+# ifdef TM_ZONE
+#  define HAVE_LOCALTIME_RZ (NETBSD_INSPIRED && USE_LTZ)
+# else
+#  define HAVE_LOCALTIME_RZ 0
+# endif
+#endif
+
+#ifndef HAVE_TZSET
+# define HAVE_TZSET 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 */
+
+#if __STDC_VERSION__ < 199901
+# define true 1
+# define false 0
+# define bool int
+#else
+# include <stdbool.h>
+#endif
+
+#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	((int_fast32_t) SECSPERHOUR * HOURSPERDAY)
+#define SECSPERNYEAR	(SECSPERDAY * DAYSPERNYEAR)
+#define SECSPERLYEAR	(SECSPERNYEAR + SECSPERDAY)
+#define SECSPER400YEARS	(SECSPERNYEAR * (intmax_t) (300 + 3)	\
+			 + SECSPERLYEAR * (intmax_t) (100 - 3))
+
+/*
+** True if SECSPER400YEARS is known to be representable as an
+** intmax_t.  It's OK that SECSPER400YEARS_FITS can in theory be false
+** even if SECSPER400YEARS is representable, because when that happens
+** the code merely runs a bit more slowly, and this slowness doesn't
+** occur on any practical platform.
+*/
+enum { SECSPER400YEARS_FITS = SECSPERLYEAR <= INTMAX_MAX / 400 };
+
+#ifndef HAVE_GETTEXT
+#define HAVE_GETTEXT 0
+#endif
+#if HAVE_GETTEXT
+#include "locale.h"	/* for setlocale */
+#include "libintl.h"
+#endif /* HAVE_GETTEXT */
+
+#if 2 < __GNUC__ || (__GNUC__ == 2 && 96 <= __GNUC_MINOR__)
+# define ATTRIBUTE_PURE __attribute__ ((__pure__))
+#else
+# define ATTRIBUTE_PURE /* empty */
+#endif
+
+/*
+** 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 _ */
+
+#if !defined TZ_DOMAIN && defined HAVE_GETTEXT
+# define TZ_DOMAIN "tz"
+#endif
+
+#if ! HAVE_LOCALTIME_RZ
+# undef  timezone_t
+# define timezone_t char **
+#endif
+
+extern char **	environ;
+extern int	getopt(int argc, char * const argv[],
+			const char * options);
+extern char *	optarg;
+extern int	optind;
+extern char *	tzname[2];
+
+/* The minimum and maximum finite time values.  */
+enum { atime_shift = CHAR_BIT * sizeof (time_t) - 2 };
+static time_t const absolute_min_time =
+  ((time_t) -1 < 0
+   ? (- ((time_t) ~ (time_t) 0 < 0)
+      - (((time_t) 1 << atime_shift) - 1 + ((time_t) 1 << atime_shift)))
+   : 0);
+static time_t const absolute_max_time =
+  ((time_t) -1 < 0
+   ? (((time_t) 1 << atime_shift) - 1 + ((time_t) 1 << atime_shift))
+   : -1);
+static int	longest;
+static char *	progname;
+static bool	warned;
+static bool	errout;
+
+static char const *abbr(struct tm const *);
+static intmax_t	delta(struct tm *, struct tm *) ATTRIBUTE_PURE;
+static void dumptime(struct tm const *);
+static time_t hunt(timezone_t, char *, time_t, time_t);
+static void show(timezone_t, char *, time_t, bool);
+static const char *tformat(void);
+static time_t yeartot(intmax_t) ATTRIBUTE_PURE;
+
+/* Unlike <ctype.h>'s isdigit, this also works if c < 0 | c > UCHAR_MAX. */
+#define is_digit(c) ((unsigned)(c) - '0' <= 9)
+
+/* Is A an alphabetic character in the C locale?  */
+static bool
+is_alpha(char a)
+{
+	switch (a) {
+	  default:
+		return false;
+	  case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': case 'G':
+	  case 'H': case 'I': case 'J': case 'K': case 'L': case 'M': case 'N':
+	  case 'O': case 'P': case 'Q': case 'R': case 'S': case 'T': case 'U':
+	  case 'V': case 'W': case 'X': case 'Y': case 'Z':
+	  case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': case 'g':
+	  case 'h': case 'i': case 'j': case 'k': case 'l': case 'm': case 'n':
+	  case 'o': case 'p': case 'q': case 'r': case 's': case 't': case 'u':
+	  case 'v': case 'w': case 'x': case 'y': case 'z':
+		return true;
+	}
+}
+
+/* Return A + B, exiting if the result would overflow.  */
+static size_t
+sumsize(size_t a, size_t b)
+{
+  size_t sum = a + b;
+  if (sum < a) {
+    fprintf(stderr, "%s: size overflow\n", progname);
+    exit(EXIT_FAILURE);
+  }
+  return sum;
+}
+
+#if ! HAVE_TZSET
+# undef tzset
+# define tzset zdump_tzset
+static void tzset(void) { }
+#endif
+
+/* Assume gmtime_r works if localtime_r does.
+   A replacement localtime_r is defined below if needed.  */
+#if ! HAVE_LOCALTIME_R
+
+# undef gmtime_r
+# define gmtime_r zdump_gmtime_r
+
+static struct tm *
+gmtime_r(time_t *tp, struct tm *tmp)
+{
+  struct tm *r = gmtime(tp);
+  if (r) {
+    *tmp = *r;
+    r = tmp;
+  }
+  return r;
+}
+
+#endif
+
+/* Platforms with TM_ZONE don't need tzname, so they can use the
+   faster localtime_rz or localtime_r if available.  */
+
+#if defined TM_ZONE && HAVE_LOCALTIME_RZ
+# define USE_LOCALTIME_RZ true
+#else
+# define USE_LOCALTIME_RZ false
+#endif
+
+#if ! USE_LOCALTIME_RZ
+
+# if !defined TM_ZONE || ! HAVE_LOCALTIME_R || ! HAVE_TZSET
+#  undef localtime_r
+#  define localtime_r zdump_localtime_r
+static struct tm *
+localtime_r(time_t *tp, struct tm *tmp)
+{
+  struct tm *r = localtime(tp);
+  if (r) {
+    *tmp = *r;
+    r = tmp;
+  }
+  return r;
+}
+# endif
+
+# undef localtime_rz
+# define localtime_rz zdump_localtime_rz
+static struct tm *
+localtime_rz(timezone_t rz, time_t *tp, struct tm *tmp)
+{
+  return localtime_r(tp, tmp);
+}
+
+# ifdef TYPECHECK
+#  undef mktime_z
+#  define mktime_z zdump_mktime_z
+static time_t
+mktime_z(timezone_t tz, struct tm *tmp)
+{
+  return mktime(tmp);
+}
+# endif
+
+# undef tzalloc
+# undef tzfree
+# define tzalloc zdump_tzalloc
+# define tzfree zdump_tzfree
+
+static timezone_t
+tzalloc(char const *val)
+{
+  static char **fakeenv;
+  char **env = fakeenv;
+  char *env0;
+  if (! env) {
+    char **e = environ;
+    int to;
+
+    while (*e++)
+      continue;
+    env = malloc(sumsize(sizeof *environ,
+			 (e - environ) * sizeof *environ));
+    if (! env) {
+      perror(progname);
+      exit(EXIT_FAILURE);
+    }
+    to = 1;
+    for (e = environ; (env[to] = *e); e++)
+      to += strncmp(*e, "TZ=", 3) != 0;
+  }
+  env0 = malloc(sumsize(sizeof "TZ=", strlen(val)));
+  if (! env0) {
+    perror(progname);
+    exit(EXIT_FAILURE);
+  }
+  env[0] = strcat(strcpy(env0, "TZ="), val);
+  environ = fakeenv = env;
+  tzset();
+  return env;
+}
+
+static void
+tzfree(timezone_t env)
+{
+  environ = env + 1;
+  free(env[0]);
+}
+#endif /* ! USE_LOCALTIME_RZ */
+
+/* A UTC time zone, and its initializer.  */
+static timezone_t gmtz;
+static void
+gmtzinit(void)
+{
+  if (USE_LOCALTIME_RZ) {
+    static char const utc[] = "UTC0";
+    gmtz = tzalloc(utc);
+    if (!gmtz) {
+      perror(utc);
+      exit(EXIT_FAILURE);
+    }
+  }
+}
+
+/* Convert *TP to UTC, storing the broken-down time into *TMP.
+   Return TMP if successful, NULL otherwise.  This is like gmtime_r(TP, TMP),
+   except typically faster if USE_LOCALTIME_RZ.  */
+static struct tm *
+my_gmtime_r(time_t *tp, struct tm *tmp)
+{
+  return USE_LOCALTIME_RZ ? localtime_rz(gmtz, tp, tmp) : gmtime_r(tp, tmp);
+}
+
+#ifndef TYPECHECK
+# define my_localtime_rz localtime_rz
+#else /* !defined TYPECHECK */
+
+static struct tm *
+my_localtime_rz(timezone_t tz, time_t *tp, struct tm *tmp)
+{
+	tmp = localtime_rz(tz, tp, tmp);
+	if (tmp) {
+		struct tm	tm;
+		register time_t	t;
+
+		tm = *tmp;
+		t = mktime_z(tz, &tm);
+		if (t != *tp) {
+			fflush(stdout);
+			fprintf(stderr, "\n%s: ", progname);
+			fprintf(stderr, tformat(), *tp);
+			fprintf(stderr, " ->");
+			fprintf(stderr, " year=%d", tmp->tm_year);
+			fprintf(stderr, " mon=%d", tmp->tm_mon);
+			fprintf(stderr, " mday=%d", tmp->tm_mday);
+			fprintf(stderr, " hour=%d", tmp->tm_hour);
+			fprintf(stderr, " min=%d", tmp->tm_min);
+			fprintf(stderr, " sec=%d", tmp->tm_sec);
+			fprintf(stderr, " isdst=%d", tmp->tm_isdst);
+			fprintf(stderr, " -> ");
+			fprintf(stderr, tformat(), t);
+			fprintf(stderr, "\n");
+			errout = true;
+		}
+	}
+	return tmp;
+}
+#endif /* !defined TYPECHECK */
+
+static void
+abbrok(const char *const abbrp, const char *const zone)
+{
+	register const char *	cp;
+	register const char *	wp;
+
+	if (warned)
+		return;
+	cp = abbrp;
+	while (is_alpha(*cp) || is_digit(*cp) || *cp == '-' || *cp == '+')
+		++cp;
+	if (cp - abbrp < 3)
+	  wp = _("has fewer than 3 characters");
+	else if (cp - abbrp > 6)
+	  wp = _("has more than 6 characters");
+	else if (*cp)
+	  wp = _("has characters other than ASCII alphanumerics, '-' or '+'");
+	else
+	  return;
+	fflush(stdout);
+	fprintf(stderr,
+		_("%s: warning: zone \"%s\" abbreviation \"%s\" %s\n"),
+		progname, zone, abbrp, wp);
+	warned = errout = true;
+}
+
+/* Return a time zone abbreviation.  If the abbreviation needs to be
+   saved, use *BUF (of size *BUFALLOC) to save it, and return the
+   abbreviation in the possibly-reallocated *BUF.  Otherwise, just
+   return the abbreviation.  Get the abbreviation from TMP.
+   Exit on memory allocation failure.  */
+static char const *
+saveabbr(char **buf, size_t *bufalloc, struct tm const *tmp)
+{
+  char const *ab = abbr(tmp);
+  if (HAVE_LOCALTIME_RZ)
+    return ab;
+  else {
+    size_t ablen = strlen(ab);
+    if (*bufalloc <= ablen) {
+      free(*buf);
+
+      /* Make the new buffer at least twice as long as the old,
+	 to avoid O(N**2) behavior on repeated calls.  */
+      *bufalloc = sumsize(*bufalloc, ablen + 1);
+
+      *buf = malloc(*bufalloc);
+      if (! *buf) {
+	perror(progname);
+	exit(EXIT_FAILURE);
+      }
+    }
+    return strcpy(*buf, ab);
+  }
+}
+
+static void
+close_file(FILE *stream)
+{
+  char const *e = (ferror(stream) ? _("I/O error")
+		   : fclose(stream) != 0 ? strerror(errno) : NULL);
+  if (e) {
+    fprintf(stderr, "%s: %s\n", progname, e);
+    exit(EXIT_FAILURE);
+  }
+}
+
+static void
+usage(FILE * const stream, const int status)
+{
+	fprintf(stream,
+_("%s: usage: %s [--version] [--help] [-{vV}] [-{ct} [lo,]hi] zonename ...\n"
+  "\n"
+  "Report bugs to %s.\n"),
+		       progname, progname, REPORT_BUGS_TO);
+	if (status == EXIT_SUCCESS)
+	  close_file(stream);
+	exit(status);
+}
+
+int
+main(int argc, char *argv[])
+{
+	/* These are static so that they're initially zero.  */
+	static char *		abbrev;
+	static size_t		abbrevsize;
+	static struct tm	newtm;
+
+	register int		i;
+	register bool		vflag;
+	register bool		Vflag;
+	register char *		cutarg;
+	register char *		cuttimes;
+	register time_t		cutlotime;
+	register time_t		cuthitime;
+	time_t			now;
+	time_t			t;
+	time_t			newt;
+	struct tm		tm;
+	register struct tm *	tmp;
+	register struct tm *	newtmp;
+
+	cutlotime = absolute_min_time;
+	cuthitime = absolute_max_time;
+#if HAVE_GETTEXT
+	setlocale(LC_ALL, "");
+#ifdef TZ_DOMAINDIR
+	bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR);
+#endif /* defined TEXTDOMAINDIR */
+	textdomain(TZ_DOMAIN);
+#endif /* HAVE_GETTEXT */
+	progname = argv[0];
+	for (i = 1; i < argc; ++i)
+		if (strcmp(argv[i], "--version") == 0) {
+			printf("zdump %s%s\n", PKGVERSION, TZVERSION);
+			return EXIT_SUCCESS;
+		} else if (strcmp(argv[i], "--help") == 0) {
+			usage(stdout, EXIT_SUCCESS);
+		}
+	vflag = Vflag = false;
+	cutarg = cuttimes = NULL;
+	for (;;)
+	  switch (getopt(argc, argv, "c:t:vV")) {
+	  case 'c': cutarg = optarg; break;
+	  case 't': cuttimes = optarg; break;
+	  case 'v': vflag = true; break;
+	  case 'V': Vflag = true; break;
+	  case -1:
+	    if (! (optind == argc - 1 && strcmp(argv[optind], "=") == 0))
+	      goto arg_processing_done;
+	    /* Fall through.  */
+	  default:
+	    usage(stderr, EXIT_FAILURE);
+	  }
+ arg_processing_done:;
+
+	if (vflag | Vflag) {
+		intmax_t	lo;
+		intmax_t	hi;
+		char *loend, *hiend;
+		register intmax_t cutloyear = ZDUMP_LO_YEAR;
+		register intmax_t cuthiyear = ZDUMP_HI_YEAR;
+		if (cutarg != NULL) {
+			lo = strtoimax(cutarg, &loend, 10);
+			if (cutarg != loend && !*loend) {
+				hi = lo;
+				cuthiyear = hi;
+			} else if (cutarg != loend && *loend == ','
+				   && (hi = strtoimax(loend + 1, &hiend, 10),
+				       loend + 1 != hiend && !*hiend)) {
+				cutloyear = lo;
+				cuthiyear = hi;
+			} else {
+				fprintf(stderr, _("%s: wild -c argument %s\n"),
+					progname, cutarg);
+				return EXIT_FAILURE;
+			}
+		}
+		if (cutarg != NULL || cuttimes == NULL) {
+			cutlotime = yeartot(cutloyear);
+			cuthitime = yeartot(cuthiyear);
+		}
+		if (cuttimes != NULL) {
+			lo = strtoimax(cuttimes, &loend, 10);
+			if (cuttimes != loend && !*loend) {
+				hi = lo;
+				if (hi < cuthitime) {
+					if (hi < absolute_min_time)
+						hi = absolute_min_time;
+					cuthitime = hi;
+				}
+			} else if (cuttimes != loend && *loend == ','
+				   && (hi = strtoimax(loend + 1, &hiend, 10),
+				       loend + 1 != hiend && !*hiend)) {
+				if (cutlotime < lo) {
+					if (absolute_max_time < lo)
+						lo = absolute_max_time;
+					cutlotime = lo;
+				}
+				if (hi < cuthitime) {
+					if (hi < absolute_min_time)
+						hi = absolute_min_time;
+					cuthitime = hi;
+				}
+			} else {
+				fprintf(stderr,
+					_("%s: wild -t argument %s\n"),
+					progname, cuttimes);
+				return EXIT_FAILURE;
+			}
+		}
+	}
+	gmtzinit();
+	now = time(NULL);
+	longest = 0;
+	for (i = optind; i < argc; i++) {
+	  size_t arglen = strlen(argv[i]);
+	  if (longest < arglen)
+	    longest = arglen < INT_MAX ? arglen : INT_MAX;
+	}
+
+	for (i = optind; i < argc; ++i) {
+		timezone_t tz = tzalloc(argv[i]);
+		char const *ab;
+		if (!tz) {
+		  perror(argv[i]);
+		  return EXIT_FAILURE;
+		}
+		if (! (vflag | Vflag)) {
+			show(tz, argv[i], now, false);
+			tzfree(tz);
+			continue;
+		}
+		warned = false;
+		t = absolute_min_time;
+		if (!Vflag) {
+			show(tz, argv[i], t, true);
+			t += SECSPERDAY;
+			show(tz, argv[i], t, true);
+		}
+		if (t < cutlotime)
+			t = cutlotime;
+		tmp = my_localtime_rz(tz, &t, &tm);
+		if (tmp)
+		  ab = saveabbr(&abbrev, &abbrevsize, &tm);
+		while (t < cuthitime) {
+			newt = ((t < absolute_max_time - SECSPERDAY / 2
+				 && t + SECSPERDAY / 2 < cuthitime)
+				? t + SECSPERDAY / 2
+				: cuthitime);
+			newtmp = localtime_rz(tz, &newt, &newtm);
+			if ((tmp == NULL || newtmp == NULL) ? (tmp != newtmp) :
+				(delta(&newtm, &tm) != (newt - t) ||
+				newtm.tm_isdst != tm.tm_isdst ||
+				strcmp(abbr(&newtm), ab) != 0)) {
+					newt = hunt(tz, argv[i], t, newt);
+					newtmp = localtime_rz(tz, &newt, &newtm);
+					if (newtmp)
+					  ab = saveabbr(&abbrev, &abbrevsize,
+							&newtm);
+			}
+			t = newt;
+			tm = newtm;
+			tmp = newtmp;
+		}
+		if (!Vflag) {
+			t = absolute_max_time;
+			t -= SECSPERDAY;
+			show(tz, argv[i], t, true);
+			t += SECSPERDAY;
+			show(tz, argv[i], t, true);
+		}
+		tzfree(tz);
+	}
+	close_file(stdout);
+	if (errout && (ferror(stderr) || fclose(stderr) != 0))
+	  return EXIT_FAILURE;
+	return EXIT_SUCCESS;
+}
+
+static time_t
+yeartot(intmax_t y)
+{
+	register intmax_t	myy, seconds, years;
+	register time_t		t;
+
+	myy = EPOCH_YEAR;
+	t = 0;
+	while (myy < y) {
+		if (SECSPER400YEARS_FITS && 400 <= y - myy) {
+			intmax_t diff400 = (y - myy) / 400;
+			if (INTMAX_MAX / SECSPER400YEARS < diff400)
+				return absolute_max_time;
+			seconds = diff400 * SECSPER400YEARS;
+			years = diff400 * 400;
+                } else {
+			seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
+			years = 1;
+		}
+		myy += years;
+		if (t > absolute_max_time - seconds)
+			return absolute_max_time;
+		t += seconds;
+	}
+	while (y < myy) {
+		if (SECSPER400YEARS_FITS && y + 400 <= myy && myy < 0) {
+			intmax_t diff400 = (myy - y) / 400;
+			if (INTMAX_MAX / SECSPER400YEARS < diff400)
+				return absolute_min_time;
+			seconds = diff400 * SECSPER400YEARS;
+			years = diff400 * 400;
+		} else {
+			seconds = isleap(myy - 1) ? SECSPERLYEAR : SECSPERNYEAR;
+			years = 1;
+		}
+		myy -= years;
+		if (t < absolute_min_time + seconds)
+			return absolute_min_time;
+		t -= seconds;
+	}
+	return t;
+}
+
+static time_t
+hunt(timezone_t tz, char *name, time_t lot, time_t hit)
+{
+	static char *		loab;
+	static size_t		loabsize;
+	char const *		ab;
+	time_t			t;
+	struct tm		lotm;
+	register struct tm *	lotmp;
+	struct tm		tm;
+	register struct tm *	tmp;
+
+	lotmp = my_localtime_rz(tz, &lot, &lotm);
+	if (lotmp)
+	  ab = saveabbr(&loab, &loabsize, &lotm);
+	for ( ; ; ) {
+		time_t diff = hit - lot;
+		if (diff < 2)
+			break;
+		t = lot;
+		t += diff / 2;
+		if (t <= lot)
+			++t;
+		else if (t >= hit)
+			--t;
+		tmp = my_localtime_rz(tz, &t, &tm);
+		if ((lotmp == NULL || tmp == NULL) ? (lotmp == tmp) :
+			(delta(&tm, &lotm) == (t - lot) &&
+			tm.tm_isdst == lotm.tm_isdst &&
+			strcmp(abbr(&tm), ab) == 0)) {
+				lot = t;
+				lotm = tm;
+				lotmp = tmp;
+		} else	hit = t;
+	}
+	show(tz, name, lot, true);
+	show(tz, name, hit, true);
+	return hit;
+}
+
+/*
+** Thanks to Paul Eggert for logic used in delta.
+*/
+
+static intmax_t
+delta(struct tm * newp, struct tm *oldp)
+{
+	register intmax_t	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;
+}
+
+#ifndef TM_GMTOFF
+/* Return A->tm_yday, adjusted to compare it fairly to B->tm_yday.
+   Assume A and B differ by at most one year.  */
+static int
+adjusted_yday(struct tm const *a, struct tm const *b)
+{
+  int yday = a->tm_yday;
+  if (b->tm_year < a->tm_year)
+    yday += 365 + isleap_sum(b->tm_year, TM_YEAR_BASE);
+  return yday;
+}
+#endif
+
+/* If A is the broken-down local time and B the broken-down UTC for
+   the same instant, return A's UTC offset in seconds, where positive
+   offsets are east of Greenwich.  On failure, return LONG_MIN.  */
+static long
+gmtoff(struct tm const *a, struct tm const *b)
+{
+#ifdef TM_GMTOFF
+  return a->TM_GMTOFF;
+#else
+  if (! b)
+    return LONG_MIN;
+  else {
+    int ayday = adjusted_yday(a, b);
+    int byday = adjusted_yday(b, a);
+    int days = ayday - byday;
+    long hours = a->tm_hour - b->tm_hour + 24 * days;
+    long minutes = a->tm_min - b->tm_min + 60 * hours;
+    long seconds = a->tm_sec - b->tm_sec + 60 * minutes;
+    return seconds;
+  }
+#endif
+}
+
+static void
+show(timezone_t tz, char *zone, time_t t, bool v)
+{
+	register struct tm *	tmp;
+	register struct tm *	gmtmp;
+	struct tm tm, gmtm;
+
+	printf("%-*s  ", longest, zone);
+	if (v) {
+		gmtmp = my_gmtime_r(&t, &gmtm);
+		if (gmtmp == NULL) {
+			printf(tformat(), t);
+		} else {
+			dumptime(gmtmp);
+			printf(" UT");
+		}
+		printf(" = ");
+	}
+	tmp = my_localtime_rz(tz, &t, &tm);
+	dumptime(tmp);
+	if (tmp != NULL) {
+		if (*abbr(tmp) != '\0')
+			printf(" %s", abbr(tmp));
+		if (v) {
+			long off = gmtoff(tmp, gmtmp);
+			printf(" isdst=%d", tmp->tm_isdst);
+			if (off != LONG_MIN)
+			  printf(" gmtoff=%ld", off);
+		}
+	}
+	printf("\n");
+	if (tmp != NULL && *abbr(tmp) != '\0')
+		abbrok(abbr(tmp), zone);
+}
+
+static char const *
+abbr(struct tm const *tmp)
+{
+#ifdef TM_ZONE
+	return tmp->TM_ZONE;
+#else
+	return (0 <= tmp->tm_isdst && tzname[0 < tmp->tm_isdst]
+		? tzname[0 < tmp->tm_isdst]
+		: "");
+#endif
+}
+
+/*
+** 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(void)
+{
+	if (0 > (time_t) -1) {		/* signed */
+		if (sizeof (time_t) == sizeof (intmax_t))
+			return "%"PRIdMAX;
+		if (sizeof (time_t) > sizeof (long))
+			return "%lld";
+		if (sizeof (time_t) > sizeof (int))
+			return "%ld";
+		return "%d";
+	}
+#ifdef PRIuMAX
+	if (sizeof (time_t) == sizeof (uintmax_t))
+		return "%"PRIuMAX;
+#endif
+	if (sizeof (time_t) > sizeof (unsigned long))
+		return "%llu";
+	if (sizeof (time_t) > sizeof (unsigned int))
+		return "%lu";
+	return "%u";
+}
+
+static void
+dumptime(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) {
+		printf("NULL");
+		return;
+	}
+	/*
+	** The packaged localtime_rz and gmtime_r 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];
+	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)
+		printf("%d", trail);
+	else	printf("%d%d", lead, ((trail < 0) ? -trail : trail));
+}