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authorZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
committerZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
commit5046dbb4a7eba5eccfd258f92f4735c9ffc8d069 (patch)
tree4470480d904b65cf14ca524f96f79eca818c3eaf /REORG.TODO/timezone/zdump.c
parent199fc19d3aaaf57944ef036e15904febe877fc93 (diff)
downloadglibc-zack/build-layout-experiment.tar.gz
glibc-zack/build-layout-experiment.tar.xz
glibc-zack/build-layout-experiment.zip
Prepare for radical source tree reorganization. zack/build-layout-experiment
All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).
Diffstat (limited to 'REORG.TODO/timezone/zdump.c')
-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));
+}