Update timezone code from tzcode 2017b.

This patch updates files coming from tzcode to the versions in tzcode
2017b.  A couple of changes to other glibc code are needed.
time/tzset.c was using the SECSPERDAY macro from tzfile.h, which no
longer defines that macro, so a local definition is added to tzset.c.
Because timezone/private.h now defines the _ macro whenever
HAVE_GETTEXT is true, even if it was previously defined, it is also
necessary to avoid a conflict with the definition in
include/libintl.h.  Defining _ISOMAC is the obvious way to avoid such
internal definitions being visible, together with defining TZ_DOMAIN
so that zic and zdump continue to get the messages from the libc
domain as desired.  However, zic and zdump rely on PKGVERSION and
REPORT_BUGS_TO from config.h, which is not included by default with
_ISOMAC, so -include config.h needs adding to the options for these
programs as well.  Together those changes allow unmodified tzcode
2017b sources to work in glibc.

Tested for x86_64.

	* timezone/private.h: Update from tzcode 2017b.
	* timezone/tzfile.h: Likewise.
	* timezone/tzselect.ksh: Likewise.
	* timezone/zdump.c: Likewise.
	* timezone/zic.c: Likewise.
	* timezone/Makefile (tz-cflags): Add -D_ISOMAC
	-DTZ_DOMAIN='"libc"' -include $(common-objpfx)config.h.
	* time/tzset.c (SECSPERDAY): New macro.

6 files changed, 864 insertions, 615 deletions

diff --git a/timezone/Makefile b/timezone/Makefile
index 35e6a95e6b..d6cc7ba357 100644
--- a/timezone/Makefile
+++ b/timezone/Makefile
@@ -59,7 +59,8 @@ tz-cflags = -DTZDIR='"$(zonedir)"' \
 	    -DTZDEFAULT='"$(localtime-file)"' \
 	    -DTZDEFRULES='"$(posixrules-file)"' \
 	    -DTM_GMTOFF=tm_gmtoff -DTM_ZONE=tm_zone \
-	    -DHAVE_GETTEXT -DUSE_LTZ=0 -Wno-maybe-uninitialized
+	    -DHAVE_GETTEXT -DUSE_LTZ=0 -D_ISOMAC -DTZ_DOMAIN='"libc"' \
+	    -include $(common-objpfx)config.h -Wno-maybe-uninitialized
 
 # The -Wno-unused-variable flag is used to prevent GCC 6
 # from warning about time_t_min and time_t_max which are
diff --git a/timezone/private.h b/timezone/private.h
index 1c176e62bc..e2f23f5f40 100644
--- a/timezone/private.h
+++ b/timezone/private.h
@@ -15,6 +15,7 @@
 ** Thank you!
 */
 
+/* This string was in the Factory zone through version 2016f.  */
 #define GRANDPARENTED	"Local time zone must be set--see zic manual page"
 
 /*
@@ -22,6 +23,10 @@
 ** You can override these in your C compiler options, e.g. '-DHAVE_GETTEXT=1'.
 */
 
+#ifndef HAVE_DECL_ASCTIME_R
+#define HAVE_DECL_ASCTIME_R 1
+#endif
+
 #ifndef HAVE_GETTEXT
 #define HAVE_GETTEXT		0
 #endif /* !defined HAVE_GETTEXT */
@@ -34,6 +39,10 @@
 #define HAVE_LINK		1
 #endif /* !defined HAVE_LINK */
 
+#ifndef HAVE_POSIX_DECLS
+#define HAVE_POSIX_DECLS 1
+#endif
+
 #ifndef HAVE_STRDUP
 #define HAVE_STRDUP 1
 #endif
@@ -69,9 +78,9 @@
 
 /* Enable tm_gmtoff and tm_zone on GNUish systems.  */
 #define _GNU_SOURCE 1
-/* Fix asctime_r on Solaris 10.  */
+/* Fix asctime_r on Solaris 11.  */
 #define _POSIX_PTHREAD_SEMANTICS 1
-/* Enable strtoimax on Solaris 10.  */
+/* Enable strtoimax on pre-C99 Solaris 11.  */
 #define __EXTENSIONS__ 1
 
 /*
@@ -95,23 +104,26 @@
 #undef tzalloc
 #undef tzfree
 
-#include "sys/types.h"	/* for time_t */
-#include "stdio.h"
-#include "string.h"
-#include "limits.h"	/* for CHAR_BIT et al. */
-#include "stdlib.h"
+#include <sys/types.h>	/* for time_t */
+#include <stdio.h>
+#include <string.h>
+#include <limits.h>	/* for CHAR_BIT et al. */
+#include <stdlib.h>
 
-#include "errno.h"
+#include <errno.h>
 
 #ifndef ENAMETOOLONG
 # define ENAMETOOLONG EINVAL
 #endif
+#ifndef ENOTSUP
+# define ENOTSUP EINVAL
+#endif
 #ifndef EOVERFLOW
 # define EOVERFLOW EINVAL
 #endif
 
 #if HAVE_GETTEXT
-#include "libintl.h"
+#include <libintl.h>
 #endif /* HAVE_GETTEXT */
 
 #if HAVE_SYS_WAIT_H
@@ -126,7 +138,7 @@
 #endif /* !defined WEXITSTATUS */
 
 #if HAVE_UNISTD_H
-#include "unistd.h"	/* for F_OK, R_OK, and other POSIX goodness */
+#include <unistd.h>	/* for F_OK, R_OK, and other POSIX goodness */
 #endif /* HAVE_UNISTD_H */
 
 #ifndef HAVE_STRFTIME_L
@@ -149,19 +161,19 @@
 
 /*
 ** Define HAVE_STDINT_H's default value here, rather than at the
-** start, since __GLIBC__'s value depends on previously-included
-** files.
-** (glibc 2.1 and later have stdint.h, even with pre-C99 compilers.)
+** start, since __GLIBC__ and INTMAX_MAX's values depend on
+** previously-included files.  glibc 2.1 and Solaris 10 and later have
+** stdint.h, even with pre-C99 compilers.
 */
 #ifndef HAVE_STDINT_H
 #define HAVE_STDINT_H \
    (199901 <= __STDC_VERSION__ \
     || 2 < __GLIBC__ + (1 <= __GLIBC_MINOR__)	\
-    || __CYGWIN__)
+    || __CYGWIN__ || INTMAX_MAX)
 #endif /* !defined HAVE_STDINT_H */
 
 #if HAVE_STDINT_H
-#include "stdint.h"
+#include <stdint.h>
 #endif /* !HAVE_STDINT_H */
 
 #ifndef HAVE_INTTYPES_H
@@ -197,14 +209,18 @@ typedef long		int_fast64_t;
 # endif
 #endif
 
-#ifndef SCNdFAST64
+#ifndef PRIdFAST64
 # if INT_FAST64_MAX == LLONG_MAX
-#  define SCNdFAST64 "lld"
+#  define PRIdFAST64 "lld"
 # else
-#  define SCNdFAST64 "ld"
+#  define PRIdFAST64 "ld"
 # endif
 #endif
 
+#ifndef SCNdFAST64
+# define SCNdFAST64 PRIdFAST64
+#endif
+
 #ifndef INT_FAST32_MAX
 # if INT_MAX >> 31 == 0
 typedef long int_fast32_t;
@@ -304,6 +320,13 @@ typedef unsigned long uintmax_t;
 ** Workarounds for compilers/systems.
 */
 
+#ifndef EPOCH_LOCAL
+# define EPOCH_LOCAL 0
+#endif
+#ifndef EPOCH_OFFSET
+# define EPOCH_OFFSET 0
+#endif
+
 /*
 ** Compile with -Dtime_tz=T to build the tz package with a private
 ** time_t type equivalent to T rather than the system-supplied time_t.
@@ -311,7 +334,7 @@ typedef unsigned long uintmax_t;
 ** (e.g., time_t wider than 'long', or unsigned time_t) even on
 ** typical platforms.
 */
-#ifdef time_tz
+#if defined time_tz || EPOCH_LOCAL || EPOCH_OFFSET != 0
 # ifdef LOCALTIME_IMPLEMENTATION
 static time_t sys_time(time_t *x) { return time(x); }
 # endif
@@ -379,25 +402,21 @@ time_t time(time_t *);
 void tzset(void);
 #endif
 
-/*
-** Some time.h implementations don't declare asctime_r.
-** Others might define it as a macro.
-** Fix the former without affecting the latter.
-** Similarly for timezone, daylight, and altzone.
-*/
-
-#ifndef asctime_r
-extern char *	asctime_r(struct tm const *restrict, char *restrict);
+#if !HAVE_DECL_ASCTIME_R && !defined asctime_r
+extern char *asctime_r(struct tm const *restrict, char *restrict);
 #endif
 
-#ifdef USG_COMPAT
-# ifndef timezone
+#if !HAVE_POSIX_DECLS
+# ifdef USG_COMPAT
+#  ifndef timezone
 extern long timezone;
-# endif
-# ifndef daylight
+#  endif
+#  ifndef daylight
 extern int daylight;
+#  endif
 # endif
 #endif
+
 #if defined ALTZONE && !defined altzone
 extern long altzone;
 #endif
@@ -481,14 +500,8 @@ time_t time2posix_z(timezone_t, time_t) ATTRIBUTE_PURE;
 # include <stdbool.h>
 #endif
 
-#ifndef TYPE_BIT
 #define TYPE_BIT(type)	(sizeof (type) * CHAR_BIT)
-#endif /* !defined TYPE_BIT */
-
-#ifndef TYPE_SIGNED
 #define TYPE_SIGNED(type) (((type) -1) < 0)
-#endif /* !defined TYPE_SIGNED */
-
 #define TWOS_COMPLEMENT(t) ((t) ~ (t) 0 < 0)
 
 /* Max and min values of the integer type T, of which only the bottom
@@ -500,11 +513,29 @@ time_t time2posix_z(timezone_t, time_t) ATTRIBUTE_PURE;
 #define MINVAL(t, b)						\
   ((t) (TYPE_SIGNED(t) ? - TWOS_COMPLEMENT(t) - MAXVAL(t, b) : 0))
 
-/* The minimum and maximum finite time values.  This assumes no padding.  */
+/* The minimum and maximum finite time values.  This implementation
+   assumes no padding if time_t is signed and either the compiler is
+   pre-C11 or time_t is not one of the standard signed integer types.  */
+#if 201112 <= __STDC_VERSION__
+static time_t const time_t_min
+  = (TYPE_SIGNED(time_t)
+     ? _Generic((time_t) 0,
+		signed char: SCHAR_MIN, short: SHRT_MIN,
+		int: INT_MIN, long: LONG_MIN, long long: LLONG_MIN,
+		default: MINVAL(time_t, TYPE_BIT(time_t)))
+     : 0);
+static time_t const time_t_max
+  = (TYPE_SIGNED(time_t)
+     ? _Generic((time_t) 0,
+		signed char: SCHAR_MAX, short: SHRT_MAX,
+		int: INT_MAX, long: LONG_MAX, long long: LLONG_MAX,
+		default: MAXVAL(time_t, TYPE_BIT(time_t)))
+     : -1);
+#else
 static time_t const time_t_min = MINVAL(time_t, TYPE_BIT(time_t));
 static time_t const time_t_max = MAXVAL(time_t, TYPE_BIT(time_t));
+#endif
 
-#ifndef INT_STRLEN_MAXIMUM
 /*
 ** 302 / 1000 is log10(2.0) rounded up.
 ** Subtract one for the sign bit if the type is signed;
@@ -514,7 +545,6 @@ static time_t const time_t_max = MAXVAL(time_t, TYPE_BIT(time_t));
 #define INT_STRLEN_MAXIMUM(type) \
 	((TYPE_BIT(type) - TYPE_SIGNED(type)) * 302 / 1000 + \
 	1 + TYPE_SIGNED(type))
-#endif /* !defined INT_STRLEN_MAXIMUM */
 
 /*
 ** INITIALIZE(x)
@@ -536,13 +566,11 @@ static time_t const time_t_max = MAXVAL(time_t, TYPE_BIT(time_t));
 ** 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"
@@ -555,24 +583,70 @@ char *asctime_r(struct tm const *, char *);
 char *ctime_r(time_t const *, char *);
 #endif /* HAVE_INCOMPATIBLE_CTIME_R */
 
-#ifndef YEARSPERREPEAT
+/* Handy macros that are independent of tzfile implementation.  */
+
 #define YEARSPERREPEAT		400	/* years before a Gregorian repeat */
-#endif /* !defined YEARSPERREPEAT */
+
+#define SECSPERMIN	60
+#define MINSPERHOUR	60
+#define HOURSPERDAY	24
+#define DAYSPERWEEK	7
+#define DAYSPERNYEAR	365
+#define DAYSPERLYEAR	366
+#define SECSPERHOUR	(SECSPERMIN * MINSPERHOUR)
+#define SECSPERDAY	((int_fast32_t) SECSPERHOUR * HOURSPERDAY)
+#define MONSPERYEAR	12
+
+#define TM_SUNDAY	0
+#define TM_MONDAY	1
+#define TM_TUESDAY	2
+#define TM_WEDNESDAY	3
+#define TM_THURSDAY	4
+#define TM_FRIDAY	5
+#define TM_SATURDAY	6
+
+#define TM_JANUARY	0
+#define TM_FEBRUARY	1
+#define TM_MARCH	2
+#define TM_APRIL	3
+#define TM_MAY		4
+#define TM_JUNE		5
+#define TM_JULY		6
+#define TM_AUGUST	7
+#define TM_SEPTEMBER	8
+#define TM_OCTOBER	9
+#define TM_NOVEMBER	10
+#define TM_DECEMBER	11
+
+#define TM_YEAR_BASE	1900
+
+#define EPOCH_YEAR	1970
+#define EPOCH_WDAY	TM_THURSDAY
+
+#define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
 
 /*
-** The Gregorian year averages 365.2425 days, which is 31556952 seconds.
+** Since everything in isleap is modulo 400 (or a factor of 400), we know that
+**	isleap(y) == isleap(y % 400)
+** and so
+**	isleap(a + b) == isleap((a + b) % 400)
+** or
+**	isleap(a + b) == isleap(a % 400 + b % 400)
+** This is true even if % means modulo rather than Fortran remainder
+** (which is allowed by C89 but not C99).
+** We use this to avoid addition overflow problems.
 */
 
-#ifndef AVGSECSPERYEAR
-#define AVGSECSPERYEAR		31556952L
-#endif /* !defined AVGSECSPERYEAR */
+#define isleap_sum(a, b)	isleap((a) % 400 + (b) % 400)
+
 
-#ifndef SECSPERREPEAT
-#define SECSPERREPEAT		((int_fast64_t) YEARSPERREPEAT * (int_fast64_t) AVGSECSPERYEAR)
-#endif /* !defined SECSPERREPEAT */
+/*
+** The Gregorian year averages 365.2425 days, which is 31556952 seconds.
+*/
 
-#ifndef SECSPERREPEAT_BITS
+#define AVGSECSPERYEAR		31556952L
+#define SECSPERREPEAT \
+  ((int_fast64_t) YEARSPERREPEAT * (int_fast64_t) AVGSECSPERYEAR)
 #define SECSPERREPEAT_BITS	34	/* ceil(log2(SECSPERREPEAT)) */
-#endif /* !defined SECSPERREPEAT_BITS */
 
 #endif /* !defined PRIVATE_H */
diff --git a/timezone/tzfile.h b/timezone/tzfile.h
index ebecd68322..0e51dce1d7 100644
--- a/timezone/tzfile.h
+++ b/timezone/tzfile.h
@@ -114,56 +114,4 @@ struct tzhead {
 #define TZ_MAX_LEAPS	50	/* Maximum number of leap second corrections */
 #endif /* !defined TZ_MAX_LEAPS */
 
-#define SECSPERMIN	60
-#define MINSPERHOUR	60
-#define HOURSPERDAY	24
-#define DAYSPERWEEK	7
-#define DAYSPERNYEAR	365
-#define DAYSPERLYEAR	366
-#define SECSPERHOUR	(SECSPERMIN * MINSPERHOUR)
-#define SECSPERDAY	((int_fast32_t) SECSPERHOUR * HOURSPERDAY)
-#define MONSPERYEAR	12
-
-#define TM_SUNDAY	0
-#define TM_MONDAY	1
-#define TM_TUESDAY	2
-#define TM_WEDNESDAY	3
-#define TM_THURSDAY	4
-#define TM_FRIDAY	5
-#define TM_SATURDAY	6
-
-#define TM_JANUARY	0
-#define TM_FEBRUARY	1
-#define TM_MARCH	2
-#define TM_APRIL	3
-#define TM_MAY		4
-#define TM_JUNE		5
-#define TM_JULY		6
-#define TM_AUGUST	7
-#define TM_SEPTEMBER	8
-#define TM_OCTOBER	9
-#define TM_NOVEMBER	10
-#define TM_DECEMBER	11
-
-#define TM_YEAR_BASE	1900
-
-#define EPOCH_YEAR	1970
-#define EPOCH_WDAY	TM_THURSDAY
-
-#define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
-
-/*
-** Since everything in isleap is modulo 400 (or a factor of 400), we know that
-**	isleap(y) == isleap(y % 400)
-** and so
-**	isleap(a + b) == isleap((a + b) % 400)
-** or
-**	isleap(a + b) == isleap(a % 400 + b % 400)
-** This is true even if % means modulo rather than Fortran remainder
-** (which is allowed by C89 but not C99).
-** We use this to avoid addition overflow problems.
-*/
-
-#define isleap_sum(a, b)	isleap((a) % 400 + (b) % 400)
-
 #endif /* !defined TZFILE_H */
diff --git a/timezone/tzselect.ksh b/timezone/tzselect.ksh
index 2c3b2f4438..d2c3a6d1dd 100755
--- a/timezone/tzselect.ksh
+++ b/timezone/tzselect.ksh
@@ -7,7 +7,7 @@ REPORT_BUGS_TO=tz@iana.org
 # Ask the user about the time zone, and output the resulting TZ value to stdout.
 # Interact with the user via stderr and stdin.
 
-# Contributed by Paul Eggert.
+# Contributed by Paul Eggert.  This file is in the public domain.
 
 # Porting notes:
 #
@@ -346,11 +346,14 @@ while
 				'that is 10 hours ahead (east) of UTC.'
 			read TZ
 			$AWK -v TZ="$TZ" 'BEGIN {
-				tzname = "[^-+,0-9][^-+,0-9][^-+,0-9]+"
-				time = "[0-2]?[0-9](:[0-5][0-9](:[0-5][0-9])?)?"
+				tzname = "(<[[:alnum:]+-]{3,}>|[[:alpha:]]{3,})"
+				time = "(2[0-4]|[0-1]?[0-9])" \
+				  "(:[0-5][0-9](:[0-5][0-9])?)?"
 				offset = "[-+]?" time
-				date = "(J?[0-9]+|M[0-9]+\\.[0-9]+\\.[0-9]+)"
-				datetime = "," date "(/" time ")?"
+				mdate = "M([1-9]|1[0-2])\\.[1-5]\\.[0-6]"
+				jdate = "((J[1-9]|[0-9]|J?[1-9][0-9]" \
+				  "|J?[1-2][0-9][0-9])|J?3[0-5][0-9]|J?36[0-5])"
+				datetime = ",(" mdate "|" jdate ")(/" time ")?"
 				tzpattern = "^(:.*|" tzname offset "(" tzname \
 				  "(" offset ")?(" datetime datetime ")?)?)$"
 				if (TZ ~ tzpattern) exit 1
@@ -509,7 +512,7 @@ while
 		case $TZsec in
 		$UTsec)
 			extra_info="
-Local time is now:	$TZdate.
+Selected time is now:	$TZdate.
 Universal Time is now:	$UTdate."
 			break
 		esac
@@ -545,7 +548,7 @@ case $SHELL in
 *) file=.profile line="TZ='$TZ'; export TZ"
 esac
 
-say >&2 "
+test -t 1 && say >&2 "
 You can make this change permanent for yourself by appending the line
 	$line
 to the file '$file' in your home directory; then log out and log in again.
diff --git a/timezone/zdump.c b/timezone/zdump.c
index 063a2635ec..bf75800101 100644
--- a/timezone/zdump.c
+++ b/timezone/zdump.c
@@ -19,89 +19,7 @@
 # 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
+#include "private.h"
 
 #ifndef HAVE_LOCALTIME_R
 # define HAVE_LOCALTIME_R 1
@@ -131,62 +49,6 @@ typedef long intmax_t;
 #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)	\
@@ -201,49 +63,24 @@ typedef long intmax_t;
 */
 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"
+#include <locale.h>	/* for setlocale */
 #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;
+
+#if !HAVE_POSIX_DECLS
 extern int	getopt(int argc, char * const argv[],
 			const char * options);
 extern char *	optarg;
 extern int	optind;
-extern char *	tzname[2];
+extern char *	tzname[];
+#endif
 
 /* The minimum and maximum finite time values.  */
 enum { atime_shift = CHAR_BIT * sizeof (time_t) - 2 };
@@ -266,6 +103,8 @@ 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 void showtrans(char const *, struct tm const *, time_t, char const *,
+		      char const *);
 static const char *tformat(void);
 static time_t yeartot(intmax_t) ATTRIBUTE_PURE;
 
@@ -303,6 +142,19 @@ sumsize(size_t a, size_t b)
   return sum;
 }
 
+/* Return a pointer to a newly allocated buffer of size SIZE, exiting
+   on failure.  SIZE should be nonzero.  */
+static void *
+xmalloc(size_t size)
+{
+  void *p = malloc(size);
+  if (!p) {
+    perror(progname);
+    exit(EXIT_FAILURE);
+  }
+