X-Git-Url: https://git.saurik.com/apple/system_cmds.git/blobdiff_plain/2fc1e207eccd68aee093ed29dae719e77bac17dd..c40d5e067506b677a9941a31cf3fadf56025c9a7:/zic.tproj/zic.c

diff --git a/zic.tproj/zic.c b/zic.tproj/zic.c
index 12659d0..75db5be 100644
--- a/zic.tproj/zic.c
+++ b/zic.tproj/zic.c
@@ -1,8 +1,13 @@
-static const char	elsieid[] = "@(#)zic.c	7.116";
+/*
+** This file is in the public domain, so clarified as of
+** 2006-07-17 by Arthur David Olson.
+*/
+
+static const char	elsieid[] = "@(#)zic.c	8.22";
 
 #ifndef lint
 static const char rcsid[] =
-  "$FreeBSD: src/usr.sbin/zic/zic.c,v 1.17 2004/10/19 20:30:09 ru Exp $";
+  "$FreeBSD: head/contrib/tzcode/zic/zic.c 214411 2010-10-27 07:14:46Z edwin $";
 #endif /* not lint */
 
 #include "private.h"
@@ -13,11 +18,19 @@ static const char rcsid[] =
 #include <sys/types.h>
 #include <unistd.h>
 
+#define	ZIC_VERSION	'2'
+
+typedef int_fast64_t	zic_t;
+
+#ifndef ZIC_MAX_ABBR_LEN_WO_WARN
+#define ZIC_MAX_ABBR_LEN_WO_WARN	6
+#endif /* !defined ZIC_MAX_ABBR_LEN_WO_WARN */
+
 #define MKDIR_UMASK (S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH)
 
 /*
 ** On some ancient hosts, predicates like `isspace(C)' are defined
-** only if isascii(C) || C == EOF.  Modern hosts obey the C Standard,
+** only if isascii(C) || C == EOF. Modern hosts obey the C Standard,
 ** which says they are defined only if C == ((unsigned char) C) || C == EOF.
 ** Neither the C Standard nor POSIX require that `isascii' exist.
 ** For portability, we check both ancient and modern requirements.
@@ -28,6 +41,11 @@ static const char rcsid[] =
 #define isascii(x) 1
 #endif
 
+#define OFFSET_STRLEN_MAXIMUM	(7 + INT_STRLEN_MAXIMUM(long))
+#define RULE_STRLEN_MAXIMUM	8	/* "Mdd.dd.d" */
+
+#define end(cp)	(strchr((cp), '\0'))
+
 struct rule {
 	const char *	r_filename;
 	int		r_linenum;
@@ -36,6 +54,8 @@ struct rule {
 	int		r_loyear;	/* for example, 1986 */
 	int		r_hiyear;	/* for example, 1986 */
 	const char *	r_yrtype;
+	int		r_lowasnum;
+	int		r_hiwasnum;
 
 	int		r_month;	/* 0..11 */
 
@@ -52,7 +72,7 @@ struct rule {
 	const char *	r_abbrvar;	/* variable part of abbreviation */
 
 	int		r_todo;		/* a rule to do (used in outzone) */
-	time_t		r_temp;		/* used in outzone */
+	zic_t		r_temp;		/* used in outzone */
 };
 
 /*
@@ -78,73 +98,81 @@ struct zone {
 	int		z_nrules;
 
 	struct rule	z_untilrule;
-	time_t		z_untiltime;
+	zic_t		z_untiltime;
 };
 
-static void	addtt P((time_t starttime, int type));
-static int	addtype P((long gmtoff, const char * abbr, int isdst,
-				int ttisstd, int ttisgmt));
-static void	leapadd P((time_t t, int positive, int rolling, int count));
-static void	adjleap P((void));
-static void	associate P((void));
-static int	ciequal P((const char * ap, const char * bp));
-static void	convert P((long val, char * buf));
-static void	dolink P((const char * fromfile, const char * tofile));
-static void	doabbr P((char * abbr, const char * format,
-			const char * letters, int isdst));
-static void	eat P((const char * name, int num));
-static void	eats P((const char * name, int num,
-			const char * rname, int rnum));
-static long	eitol P((int i));
-static void	error P((const char * message));
-static char **	getfields P((char * buf));
-static long	gethms P((const char * string, const char * errstrng,
-			int signable));
-static void	infile P((const char * filename));
-static void	inleap P((char ** fields, int nfields));
-static void	inlink P((char ** fields, int nfields));
-static void	inrule P((char ** fields, int nfields));
-static int	inzcont P((char ** fields, int nfields));
-static int	inzone P((char ** fields, int nfields));
-static int	inzsub P((char ** fields, int nfields, int iscont));
-static int	itsabbr P((const char * abbr, const char * word));
-static int	itsdir P((const char * name));
-static int	lowerit P((int c));
-static char *	memcheck P((char * tocheck));
-static int	mkdirs P((char * filename));
-static void	newabbr P((const char * abbr));
-static long	oadd P((long t1, long t2));
-static void	outzone P((const struct zone * zp, int ntzones));
-static void	puttzcode P((long code, FILE * fp));
-static int	rcomp P((const void * leftp, const void * rightp));
-static time_t	rpytime P((const struct rule * rp, int wantedy));
-static void	rulesub P((struct rule * rp,
+static void	addtt(zic_t starttime, int type);
+static int	addtype(long gmtoff, const char * abbr, int isdst,
+				int ttisstd, int ttisgmt);
+static void	leapadd(zic_t t, int positive, int rolling, int count);
+static void	adjleap(void);
+static void	associate(void);
+static int	ciequal(const char * ap, const char * bp);
+static void	convert(long val, char * buf);
+static void	convert64(zic_t val, char * buf);
+static void	dolink(const char * fromfield, const char * tofield);
+static void	doabbr(char * abbr, const char * format,
+			const char * letters, int isdst, int doquotes);
+static void	eat(const char * name, int num);
+static void	eats(const char * name, int num,
+			const char * rname, int rnum);
+static long	eitol(int i);
+static void	error(const char * message);
+static char **	getfields(char * buf);
+static long	gethms(const char * string, const char * errstrng,
+			int signable);
+static void	infile(const char * filename);
+static void	inleap(char ** fields, int nfields);
+static void	inlink(char ** fields, int nfields);
+static void	inrule(char ** fields, int nfields);
+static int	inzcont(char ** fields, int nfields);
+static int	inzone(char ** fields, int nfields);
+static int	inzsub(char ** fields, int nfields, int iscont);
+static int	is32(zic_t x);
+static int	itsabbr(const char * abbr, const char * word);
+static int	itsdir(const char * name);
+static int	lowerit(int c);
+static char *	memcheck(char * tocheck);
+static int	mkdirs(char * filename);
+static void	newabbr(const char * abbr);
+static long	oadd(long t1, long t2);
+static void	outzone(const struct zone * zp, int ntzones);
+static void	puttzcode(long code, FILE * fp);
+static void	puttzcode64(zic_t code, FILE * fp);
+static int	rcomp(const void * leftp, const void * rightp);
+static zic_t	rpytime(const struct rule * rp, int wantedy);
+static void	rulesub(struct rule * rp,
 			const char * loyearp, const char * hiyearp,
 			const char * typep, const char * monthp,
-			const char * dayp, const char * timep));
-static void	setboundaries P((void));
-static void	setgroup P((gid_t *flag, const char *name));
-static void	setuser P((uid_t *flag, const char *name));
-static time_t	tadd P((time_t t1, long t2));
-static void	usage P((void));
-static void	writezone P((const char * name));
-static int	yearistype P((int year, const char * type));
-
-#if !(HAVE_STRERROR - 0)
-static char *	strerror P((int));
-#endif /* !(HAVE_STRERROR - 0) */
+			const char * dayp, const char * timep);
+static int 	stringoffset(char * result, long offset);
+static int	stringrule(char * result, const struct rule * rp,
+			long dstoff, long gmtoff);
+static void 	stringzone(char * result,
+			const struct zone * zp, int ntzones);
+static void	setboundaries(void);
+static void	setgroup(gid_t *flag, const char *name);
+static void	setuser(uid_t *flag, const char *name);
+static zic_t	tadd(zic_t t1, long t2);
+static void	usage(FILE *stream, int status);
+static void	writezone(const char * name, const char * string);
+static int	yearistype(int year, const char * type);
 
 static int		charcnt;
 static int		errors;
 static const char *	filename;
 static int		leapcnt;
+static int		leapseen;
+static int		leapminyear;
+static int		leapmaxyear;
 static int		linenum;
-static time_t		max_time;
+static int		max_abbrvar_len;
+static int		max_format_len;
+static zic_t		max_time;
 static int		max_year;
-static int		max_year_representable;
-static time_t		min_time;
+static zic_t		min_time;
 static int		min_year;
-static int		min_year_representable;
+static zic_t		min_time;
 static int		noise;
 static const char *	rfilename;
 static int		rlinenum;
@@ -253,8 +281,8 @@ struct lookup {
 	const int	l_value;
 };
 
-static struct lookup const *	byword P((const char * string,
-					const struct lookup * lp));
+static struct lookup const *	byword(const char * string,
+					const struct lookup * lp);
 
 static struct lookup const	line_codes[] = {
 	{ "Rule",	LC_RULE },
@@ -331,7 +359,7 @@ static const int	len_years[2] = {
 };
 
 static struct attype {
-	time_t		at;
+	zic_t		at;
 	unsigned char	type;
 }			attypes[TZ_MAX_TIMES];
 static long		gmtoffs[TZ_MAX_TYPES];
@@ -340,7 +368,7 @@ static unsigned char	abbrinds[TZ_MAX_TYPES];
 static char		ttisstds[TZ_MAX_TYPES];
 static char		ttisgmts[TZ_MAX_TYPES];
 static char		chars[TZ_MAX_CHARS];
-static time_t		trans[TZ_MAX_LEAPS];
+static zic_t		trans[TZ_MAX_LEAPS];
 static long		corr[TZ_MAX_LEAPS];
 static char		roll[TZ_MAX_LEAPS];
 
@@ -366,19 +394,6 @@ char * const	ptr;
 ** Error handling.
 */
 
-#if !(HAVE_STRERROR - 0)
-static char *
-strerror(errnum)
-int	errnum;
-{
-	extern char *	sys_errlist[];
-	extern int	sys_nerr;
-
-	return (errnum > 0 && errnum <= sys_nerr) ?
-		sys_errlist[errnum] : _("Unknown system error");
-}
-#endif /* !(HAVE_STRERROR - 0) */
-
 static void
 eats(name, num, rname, rnum)
 const char * const	name;
@@ -432,12 +447,14 @@ const char * const	string;
 }
 
 static void
-usage P((void))
-{
-	(void) fprintf(stderr, "%s\n%s\n",
-_("usage: zic [--version] [-s] [-v] [-l localtime] [-p posixrules] [-d directory]"),
-_("           [-L leapseconds] [-y yearistype] [filename ... ]"));
-	(void) exit(EXIT_FAILURE);
+usage(FILE *stream, int status)
+  {
+	(void) fprintf(stream, _("usage is zic \
+[ --version ] [--help] [ -v ] [ -l localtime ] [ -p posixrules ] \\\n\
+\t[ -d directory ] [ -L leapseconds ] [ -y yearistype ] [ filename ... ]\n\
+\n\
+Report bugs to tz@elsie.nci.nih.gov.\n"));
+	exit(status);
 }
 
 static const char *	psxrules;
@@ -445,7 +462,6 @@ static const char *	lcltime;
 static const char *	directory;
 static const char *	leapsec;
 static const char *	yitcommand;
-static int		sflag = FALSE;
 static int		Dflag;
 static uid_t		uflag = (uid_t)-1;
 static gid_t		gflag = (gid_t)-1;
@@ -464,21 +480,28 @@ char *	argv[];
 #ifdef unix
 	(void) umask(umask(S_IWGRP | S_IWOTH) | (S_IWGRP | S_IWOTH));
 #endif /* defined unix */
-#if HAVE_GETTEXT - 0
-	(void) setlocale(LC_MESSAGES, "");
+#if HAVE_GETTEXT
+	(void) setlocale(LC_ALL, "");
 #ifdef TZ_DOMAINDIR
 	(void) bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR);
 #endif /* defined TEXTDOMAINDIR */
 	(void) textdomain(TZ_DOMAIN);
-#endif /* HAVE_GETTEXT - 0 */
+#endif /* HAVE_GETTEXT */
+	if (TYPE_BIT(zic_t) < 64) {
+		(void) fprintf(stderr, "zic: %s\n",
+			_("wild compilation-time specification of zic_t"));
+		exit(EXIT_FAILURE);
+	}
 	for (i = 1; i < argc; ++i)
 		if (strcmp(argv[i], "--version") == 0) {
 			errx(EXIT_SUCCESS, "%s", elsieid);
+ 		} else if (strcmp(argv[i], "--help") == 0) {
+ 			usage(stdout, EXIT_SUCCESS);
 		}
 	while ((c = getopt(argc, argv, "Dd:g:l:m:p:L:u:vsy:")) != -1)
 		switch (c) {
 			default:
-				usage();
+				usage(stderr, EXIT_FAILURE);
 			case 'D':
 				Dflag = 1;
 				break;
@@ -537,11 +560,11 @@ _("more than one -L option specified"));
 				noise = TRUE;
 				break;
 			case 's':
-				sflag = TRUE;
+				(void) printf("zic: -s ignored\n");
 				break;
 		}
 	if (optind == argc - 1 && strcmp(argv[optind], "=") == 0)
-		usage();	/* usage message by request */
+		usage(stderr, EXIT_FAILURE);	/* usage message by request */
 	if (directory == NULL)
 		directory = TZDIR;
 	if (yitcommand == NULL)
@@ -557,7 +580,7 @@ _("more than one -L option specified"));
 	for (i = optind; i < argc; ++i)
 		infile(argv[i]);
 	if (errors)
-		(void) exit(EXIT_FAILURE);
+		exit(EXIT_FAILURE);
 	associate();
 	for (i = 0; i < nzones; i = j) {
 		/*
@@ -573,6 +596,11 @@ _("more than one -L option specified"));
 	for (i = 0; i < nlinks; ++i) {
 		eat(links[i].l_filename, links[i].l_linenum);
 		dolink(links[i].l_from, links[i].l_to);
+		if (noise)
+			for (j = 0; j < nlinks; ++j)
+				if (strcmp(links[i].l_to,
+					links[j].l_from) == 0)
+						warning(_("link to link"));
 	}
 	if (lcltime != NULL) {
 		eat("command line", 1);
@@ -586,26 +614,26 @@ _("more than one -L option specified"));
 }
 
 static void
-dolink(fromfile, tofile)
-const char * const	fromfile;
-const char * const	tofile;
+dolink(fromfield, tofield)
+const char * const	fromfield;
+const char * const	tofield;
 {
 	register char *	fromname;
 	register char *	toname;
 
-	if (fromfile[0] == '/')
-		fromname = ecpyalloc(fromfile);
+	if (fromfield[0] == '/')
+		fromname = ecpyalloc(fromfield);
 	else {
 		fromname = ecpyalloc(directory);
 		fromname = ecatalloc(fromname, "/");
-		fromname = ecatalloc(fromname, fromfile);
+		fromname = ecatalloc(fromname, fromfield);
 	}
-	if (tofile[0] == '/')
-		toname = ecpyalloc(tofile);
+	if (tofield[0] == '/')
+		toname = ecpyalloc(tofield);
 	else {
 		toname = ecpyalloc(directory);
 		toname = ecatalloc(toname, "/");
-		toname = ecatalloc(toname, tofile);
+		toname = ecatalloc(toname, tofield);
 	}
 	/*
 	** We get to be careful here since
@@ -617,25 +645,30 @@ const char * const	tofile;
 		int	result;
 
 		if (mkdirs(toname) != 0)
-			(void) exit(EXIT_FAILURE);
+			exit(EXIT_FAILURE);
 
 		result = link(fromname, toname);
-#if (HAVE_SYMLINK - 0)
+#if HAVE_SYMLINK
 		if (result != 0 &&
-		    access(fromname, F_OK) == 0 &&
-		    !itsdir(fromname)) {
-		        const char *s = tofile;
-		        register char * symlinkcontents = NULL;
-		        while ((s = strchr(s+1, '/')) != NULL)
-			        symlinkcontents = ecatalloc(symlinkcontents, "../");
-			symlinkcontents = ecatalloc(symlinkcontents, fromfile);
-
-			result = symlink(symlinkcontents, toname);
-			if (result == 0)
+			access(fromname, F_OK) == 0 &&
+			!itsdir(fromname)) {
+				const char *s = tofield;
+				register char * symlinkcontents = NULL;
+				while ((s = strchr(s+1, '/')) != NULL)
+					symlinkcontents =
+						ecatalloc(symlinkcontents,
+						"../");
+				symlinkcontents =
+					ecatalloc(symlinkcontents,
+					fromname);
+				result =
+					symlink(symlinkcontents,
+					toname);
+				if (result == 0)
 warning(_("hard link failed, symbolic link used"));
-			ifree(symlinkcontents);
+				ifree(symlinkcontents);
 		}
-#endif
+#endif /* HAVE_SYMLINK */
 		if (result != 0) {
 			err(EXIT_FAILURE, _("can't link from %s to %s"),
 			    fromname, toname);
@@ -645,43 +678,17 @@ warning(_("hard link failed, symbolic link used"));
 	ifree(toname);
 }
 
-#ifndef INT_MAX
-#define INT_MAX	((int) (((unsigned)~0)>>1))
-#endif /* !defined INT_MAX */
-
-#ifndef INT_MIN
-#define INT_MIN	((int) ~(((unsigned)~0)>>1))
-#endif /* !defined INT_MIN */
-
-/*
-** The tz file format currently allows at most 32-bit quantities.
-** This restriction should be removed before signed 32-bit values
-** wrap around in 2038, but unfortunately this will require a
-** change to the tz file format.
-*/
-
-#define MAX_BITS_IN_FILE	32
-#define TIME_T_BITS_IN_FILE	((TYPE_BIT(time_t) < MAX_BITS_IN_FILE) ? TYPE_BIT(time_t) : MAX_BITS_IN_FILE)
+#define TIME_T_BITS_IN_FILE	64
 
 static void
-setboundaries P((void))
+setboundaries (void)
 {
-	if (TYPE_SIGNED(time_t)) {
-		min_time = ~ (time_t) 0;
-		min_time <<= TIME_T_BITS_IN_FILE - 1;
-		max_time = ~ (time_t) 0 - min_time;
-		if (sflag)
-			min_time = 0;
-	} else {
-		min_time = 0;
-		max_time = 2 - sflag;
-		max_time <<= TIME_T_BITS_IN_FILE - 1;
-		--max_time;
-	}
-	min_year = TM_YEAR_BASE + gmtime(&min_time)->tm_year;
-	max_year = TM_YEAR_BASE + gmtime(&max_time)->tm_year;
-	min_year_representable = min_year;
-	max_year_representable = max_year;
+	register int	i;
+
+	min_time = -1;
+	for (i = 0; i < TIME_T_BITS_IN_FILE - 1; ++i)
+		min_time *= 2;
+	max_time = -(min_time + 1);
 }
 
 static int
@@ -716,7 +723,7 @@ const void *	cp2;
 }
 
 static void
-associate P((void))
+associate(void)
 {
 	register struct zone *	zp;
 	register struct rule *	rp;
@@ -778,7 +785,7 @@ associate P((void))
 			*/
 			eat(zp->z_filename, zp->z_linenum);
 			zp->z_stdoff = gethms(zp->z_rule, _("unruly zone"),
-					      TRUE);
+				TRUE);
 			/*
 			** Note, though, that if there's no rule,
 			** a '%s' in the format is a bad thing.
@@ -788,7 +795,7 @@ associate P((void))
 		}
 	}
 	if (errors)
-		(void) exit(EXIT_FAILURE);
+		exit(EXIT_FAILURE);
 }
 
 static void
@@ -817,7 +824,7 @@ const char *	name;
 		cp = strchr(buf, '\n');
 		if (cp == NULL) {
 			error(_("line too long"));
-			(void) exit(EXIT_FAILURE);
+			exit(EXIT_FAILURE);
 		}
 		*cp = '\0';
 		fields = getfields(buf);
@@ -885,7 +892,8 @@ const char *		string;
 const char * const	errstring;
 const int		signable;
 {
-	int	hh, mm, ss, sign;
+	long	hh;
+	int	mm, ss, sign;
 
 	if (string == NULL || *string == '\0')
 		return 0;
@@ -895,27 +903,32 @@ const int		signable;
 		sign = -1;
 		++string;
 	} else	sign = 1;
-	if (sscanf(string, scheck(string, "%d"), &hh) == 1)
+	if (sscanf(string, scheck(string, "%ld"), &hh) == 1)
 		mm = ss = 0;
-	else if (sscanf(string, scheck(string, "%d:%d"), &hh, &mm) == 2)
+	else if (sscanf(string, scheck(string, "%ld:%d"), &hh, &mm) == 2)
 		ss = 0;
-	else if (sscanf(string, scheck(string, "%d:%d:%d"),
+	else if (sscanf(string, scheck(string, "%ld:%d:%d"),
 		&hh, &mm, &ss) != 3) {
 			error(errstring);
 			return 0;
 	}
-	if ((hh < 0 || hh >= HOURSPERDAY ||
+	if (hh < 0 ||
 		mm < 0 || mm >= MINSPERHOUR ||
-		ss < 0 || ss > SECSPERMIN) &&
-		!(hh == HOURSPERDAY && mm == 0 && ss == 0)) {
+		ss < 0 || ss > SECSPERMIN) {
 			error(errstring);
 			return 0;
 	}
-	if (noise && hh == HOURSPERDAY)
+	if (LONG_MAX / SECSPERHOUR < hh) {
+		error(_("time overflow"));
+		return 0;
+	}
+	if (noise && hh == HOURSPERDAY && mm == 0 && ss == 0)
 		warning(_("24:00 not handled by pre-1998 versions of zic"));
-	return eitol(sign) *
-		(eitol(hh * MINSPERHOUR + mm) *
-		eitol(SECSPERMIN) + eitol(ss));
+	if (noise && (hh > HOURSPERDAY ||
+		(hh == HOURSPERDAY && (mm != 0 || ss != 0))))
+warning(_("values over 24 hours not handled by pre-2007 versions of zic"));
+	return oadd(eitol(sign) * hh * eitol(SECSPERHOUR),
+		    eitol(sign) * (eitol(mm) * eitol(SECSPERMIN) + eitol(ss)));
 }
 
 static void
@@ -940,6 +953,8 @@ const int		nfields;
 		fields[RF_MONTH], fields[RF_DAY], fields[RF_TOD]);
 	r.r_name = ecpyalloc(fields[RF_NAME]);
 	r.r_abbrvar = ecpyalloc(fields[RF_ABBRVAR]);
+	if (max_abbrvar_len < strlen(r.r_abbrvar))
+		max_abbrvar_len = strlen(r.r_abbrvar);
 	rules = (struct rule *) (void *) erealloc((char *) rules,
 		(int) ((nrules + 1) * sizeof *rules));
 	rules[nrules++] = r;
@@ -1045,6 +1060,8 @@ const int		iscont;
 	}
 	z.z_rule = ecpyalloc(fields[i_rule]);
 	z.z_format = ecpyalloc(fields[i_format]);
+	if (max_format_len < strlen(z.z_format))
+		max_format_len = strlen(z.z_format);
 	hasuntil = nfields > i_untilyear;
 	if (hasuntil) {
 		z.z_untilrule.r_filename = filename;
@@ -1065,7 +1082,9 @@ const int		iscont;
 			zones[nzones - 1].z_untiltime > min_time &&
 			zones[nzones - 1].z_untiltime < max_time &&
 			zones[nzones - 1].z_untiltime >= z.z_untiltime) {
-				error(_("Zone continuation line end time is not after end time of previous line"));
+				error(_(
+"Zone continuation line end time is not after end time of previous line"
+					));
 				return FALSE;
 		}
 	}
@@ -1089,7 +1108,7 @@ const int		nfields;
 	register int			i, j;
 	int				year, month, day;
 	long				dayoff, tod;
-	time_t				t;
+	zic_t				t;
 
 	if (nfields != LEAP_FIELDS) {
 		error(_("wrong number of fields on Leap line"));
@@ -1098,12 +1117,17 @@ const int		nfields;
 	dayoff = 0;
 	cp = fields[LP_YEAR];
 	if (sscanf(cp, scheck(cp, "%d"), &year) != 1) {
-			/*
-			 * Leapin' Lizards!
-			 */
-			error(_("invalid leaping year"));
-			return;
+		/*
+		** Leapin' Lizards!
+		*/
+		error(_("invalid leaping year"));
+		return;
 	}
+	if (!leapseen || leapmaxyear < year)
+		leapmaxyear = year;
+	if (!leapseen || leapminyear > year)
+		leapminyear = year;
+	leapseen = TRUE;
 	j = EPOCH_YEAR;
 	while (j != year) {
 		if (year > j) {
@@ -1133,7 +1157,7 @@ const int		nfields;
 			return;
 	}
 	dayoff = oadd(dayoff, eitol(day - 1));
-	if (dayoff < 0 && !TYPE_SIGNED(time_t)) {
+	if (dayoff < 0 && !TYPE_SIGNED(zic_t)) {
 		error(_("time before zero"));
 		return;
 	}
@@ -1145,7 +1169,7 @@ const int		nfields;
 		error(_("time too large"));
 		return;
 	}
-	t = (time_t) dayoff * SECSPERDAY;
+	t = (zic_t) dayoff * SECSPERDAY;
 	tod = gethms(fields[LP_TIME], _("invalid time of day"), FALSE);
 	cp = fields[LP_CORR];
 	{
@@ -1169,7 +1193,9 @@ const int		nfields;
 			return;
 		}
 		if ((lp = byword(fields[LP_ROLL], leap_types)) == NULL) {
-			error(_("illegal Rolling/Stationary field on Leap line"));
+			error(_(
+				"illegal Rolling/Stationary field on Leap line"
+				));
 			return;
 		}
 		leapadd(tadd(t, tod), positive, lp->l_value, count);
@@ -1256,7 +1282,8 @@ const char * const		timep;
 	*/
 	cp = loyearp;
 	lp = byword(cp, begin_years);
-	if (lp != NULL) switch ((int) lp->l_value) {
+	rp->r_lowasnum = lp == NULL;
+	if (!rp->r_lowasnum) switch ((int) lp->l_value) {
 		case YR_MINIMUM:
 			rp->r_loyear = INT_MIN;
 			break;
@@ -1269,14 +1296,11 @@ const char * const		timep;
 	} else if (sscanf(cp, scheck(cp, "%d"), &rp->r_loyear) != 1) {
 		error(_("invalid starting year"));
 		return;
-	} else if (noise) {
-		if (rp->r_loyear < min_year_representable)
-			warning(_("starting year too low to be represented"));
-		else if (rp->r_loyear > max_year_representable)
-			warning(_("starting year too high to be represented"));
 	}
 	cp = hiyearp;
-	if ((lp = byword(cp, end_years)) != NULL) switch ((int) lp->l_value) {
+	lp = byword(cp, end_years);
+	rp->r_hiwasnum = lp == NULL;
+	if (!rp->r_hiwasnum) switch ((int) lp->l_value) {
 		case YR_MINIMUM:
 			rp->r_hiyear = INT_MIN;
 			break;
@@ -1292,11 +1316,6 @@ const char * const		timep;
 	} else if (sscanf(cp, scheck(cp, "%d"), &rp->r_hiyear) != 1) {
 		error(_("invalid ending year"));
 		return;
-	} else if (noise) {
-		if (rp->r_loyear < min_year_representable)
-			warning(_("ending year too low to be represented"));
-		else if (rp->r_loyear > max_year_representable)
-			warning(_("ending year too high to be represented"));
 	}
 	if (rp->r_loyear > rp->r_hiyear) {
 		error(_("starting year greater than ending year"));
@@ -1311,8 +1330,6 @@ const char * const		timep;
 		}
 		rp->r_yrtype = ecpyalloc(typep);
 	}
-	if (rp->r_loyear < min_year && rp->r_loyear > 0)
-		min_year = rp->r_loyear;
 	/*
 	** Day work.
 	** Accept things such as:
@@ -1366,12 +1383,24 @@ const long	val;
 char * const	buf;
 {
 	register int	i;
-	register long	shift;
+	register int	shift;
 
 	for (i = 0, shift = 24; i < 4; ++i, shift -= 8)
 		buf[i] = val >> shift;
 }
 
+static void
+convert64(val, buf)
+const zic_t	val;
+char * const	buf;
+{
+	register int	i;
+	register int	shift;
+
+	for (i = 0, shift = 56; i < 8; ++i, shift -= 8)
+		buf[i] = val >> shift;
+}
+
 static void
 puttzcode(val, fp)
 const long	val;
@@ -1383,28 +1412,50 @@ FILE * const	fp;
 	(void) fwrite((void *) buf, (size_t) sizeof buf, (size_t) 1, fp);
 }
 
+static void
+puttzcode64(val, fp)
+const zic_t	val;
+FILE * const	fp;
+{
+	char	buf[8];
+
+	convert64(val, buf);
+	(void) fwrite((void *) buf, (size_t) sizeof buf, (size_t) 1, fp);
+}
+
 static int
 atcomp(avp, bvp)
-void *	avp;
-void *	bvp;
+const void *	avp;
+const void *	bvp;
 {
-	if (((struct attype *) avp)->at < ((struct attype *) bvp)->at)
-		return -1;
-	else if (((struct attype *) avp)->at > ((struct attype *) bvp)->at)
-		return 1;
-	else	return 0;
+	const zic_t	a = ((const struct attype *) avp)->at;
+	const zic_t	b = ((const struct attype *) bvp)->at;
+
+	return (a < b) ? -1 : (a > b);
+}
+
+static int
+is32(x)
+const zic_t	x;
+{
+	return INT32_MIN <= x && x <= INT32_MAX;
 }
 
 static void
-writezone(name)
+writezone(name, string)
 const char * const	name;
+const char * const	string;
 {
-	register FILE *		fp;
-	register int		i, j;
-	static char *		fullname;
-	static struct tzhead	tzh;
-	time_t			ats[TZ_MAX_TIMES];
-	unsigned char		types[TZ_MAX_TIMES];
+	register FILE *			fp;
+	register int			i, j;
+	register int			leapcnt32, leapi32;
+	register int			timecnt32, timei32;
+	register int			pass;
+	static char *			fullname;
+	static const struct tzhead	tzh0;
+	static struct tzhead		tzh;
+	zic_t				ats[TZ_MAX_TIMES];
+	unsigned char			types[TZ_MAX_TIMES];
 
 	/*
 	** Sort.
@@ -1427,14 +1478,13 @@ const char * const	name;
 			while (fromi < timecnt && attypes[fromi].type == 0)
 				++fromi;	/* handled by default rule */
 		for ( ; fromi < timecnt; ++fromi) {
-			if (toi != 0
-			    && ((attypes[fromi].at
-				 + gmtoffs[attypes[toi - 1].type])
-				<= (attypes[toi - 1].at
-				    + gmtoffs[toi == 1 ? 0
-					      : attypes[toi - 2].type]))) {
-				attypes[toi - 1].type = attypes[fromi].type;
-				continue;
+			if (toi != 0 && ((attypes[fromi].at +
+				gmtoffs[attypes[toi - 1].type]) <=
+				(attypes[toi - 1].at + gmtoffs[toi == 1 ? 0
+				: attypes[toi - 2].type]))) {
+					attypes[toi - 1].type =
+						attypes[fromi].type;
+					continue;
 			}
 			if (toi == 0 ||
 				attypes[toi - 1].type != attypes[fromi].type)
@@ -1449,6 +1499,36 @@ const char * const	name;
 		ats[i] = attypes[i].at;
 		types[i] = attypes[i].type;
 	}
+	/*
+	** Correct for leap seconds.
+	*/
+	for (i = 0; i < timecnt; ++i) {
+		j = leapcnt;
+		while (--j >= 0)
+			if (ats[i] > trans[j] - corr[j]) {
+				ats[i] = tadd(ats[i], corr[j]);
+				break;
+			}
+	}
+	/*
+	** Figure out 32-bit-limited starts and counts.
+	*/
+	timecnt32 = timecnt;
+	timei32 = 0;
+	leapcnt32 = leapcnt;
+	leapi32 = 0;
+	while (timecnt32 > 0 && !is32(ats[timecnt32 - 1]))
+		--timecnt32;
+	while (timecnt32 > 0 && !is32(ats[timei32])) {
+		--timecnt32;
+		++timei32;
+	}
+	while (leapcnt32 > 0 && !is32(trans[leapcnt32 - 1]))
+		--leapcnt32;
+	while (leapcnt32 > 0 && !is32(trans[leapi32])) {
+		--leapcnt32;
+		++leapi32;
+	}
 	fullname = erealloc(fullname,
 		(int) (strlen(directory) + 1 + strlen(name) + 1));
 	(void) sprintf(fullname, "%s/%s", directory, name);
@@ -1461,70 +1541,201 @@ const char * const	name;
 
 	if ((fp = fopen(fullname, "wb")) == NULL) {
 		if (mkdirs(fullname) != 0)
-			(void) exit(EXIT_FAILURE);
+			exit(EXIT_FAILURE);
 		if ((fp = fopen(fullname, "wb")) == NULL)
 			err(EXIT_FAILURE, _("can't create %s"), fullname);
 	}
-	convert(eitol(typecnt), tzh.tzh_ttisgmtcnt);
-	convert(eitol(typecnt), tzh.tzh_ttisstdcnt);
-	convert(eitol(leapcnt), tzh.tzh_leapcnt);
-	convert(eitol(timecnt), tzh.tzh_timecnt);
-	convert(eitol(typecnt), tzh.tzh_typecnt);
-	convert(eitol(charcnt), tzh.tzh_charcnt);
-	(void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
-#define DO(field)	(void) fwrite((void *) tzh.field, (size_t) sizeof tzh.field, (size_t) 1, fp)
-	DO(tzh_magic);
-	DO(tzh_reserved);
-	DO(tzh_ttisgmtcnt);
-	DO(tzh_ttisstdcnt);
-	DO(tzh_leapcnt);
-	DO(tzh_timecnt);
-	DO(tzh_typecnt);
-	DO(tzh_charcnt);
-#undef DO
-	for (i = 0; i < timecnt; ++i) {
-		j = leapcnt;
-		while (--j >= 0)
-			if (ats[i] >= trans[j]) {
-				ats[i] = tadd(ats[i], corr[j]);
-				break;
+	for (pass = 1; pass <= 2; ++pass) {
+		register int	thistimei, thistimecnt;
+		register int	thisleapi, thisleapcnt;
+		register int	thistimelim, thisleaplim;
+		int		writetype[TZ_MAX_TIMES];
+		int		typemap[TZ_MAX_TYPES];
+		register int	thistypecnt;
+		char		thischars[TZ_MAX_CHARS];
+		char		thischarcnt;
+		int 		indmap[TZ_MAX_CHARS];
+
+		if (pass == 1) {
+			thistimei = timei32;
+			thistimecnt = timecnt32;
+			thisleapi = leapi32;
+			thisleapcnt = leapcnt32;
+		} else {
+			thistimei = 0;
+			thistimecnt = timecnt;
+			thisleapi = 0;
+			thisleapcnt = leapcnt;
+		}
+		thistimelim = thistimei + thistimecnt;
+		thisleaplim = thisleapi + thisleapcnt;
+		for (i = 0; i < typecnt; ++i)
+			writetype[i] = thistimecnt == timecnt;
+		if (thistimecnt == 0) {
+			/*
+			** No transition times fall in the current
+			** (32- or 64-bit) window.
+			*/
+			if (typecnt != 0)
+				writetype[typecnt - 1] = TRUE;
+		} else {
+			for (i = thistimei - 1; i < thistimelim; ++i)
+				if (i >= 0)
+					writetype[types[i]] = TRUE;
+			/*
+			** For America/Godthab and Antarctica/Palmer
+			*/
+			if (thistimei == 0)
+				writetype[0] = TRUE;
+		}
+#ifndef LEAVE_SOME_PRE_2011_SYSTEMS_IN_THE_LURCH
+		/*
+		** For some pre-2011 systems: if the last-to-be-written
+		** standard (or daylight) type has an offset different from the
+		** most recently used offset,
+		** append an (unused) copy of the most recently used type
+		** (to help get global "altzone" and "timezone" variables
+		** set correctly).
+		*/
+		{
+			register int	mrudst, mrustd, hidst, histd, type;
+
+			hidst = histd = mrudst = mrustd = -1;
+			for (i = thistimei; i < thistimelim; ++i)
+				if (isdsts[types[i]])
+					mrudst = types[i];
+				else	mrustd = types[i];
+			for (i = 0; i < typecnt; ++i)
+				if (writetype[i]) {
+					if (isdsts[i])
+						hidst = i;
+					else	histd = i;
+				}
+			if (hidst >= 0 && mrudst >= 0 && hidst != mrudst &&
+				gmtoffs[hidst] != gmtoffs[mrudst]) {
+					isdsts[mrudst] = -1;
+					type = addtype(gmtoffs[mrudst],
+						&chars[abbrinds[mrudst]],
+						TRUE,
+						ttisstds[mrudst],
+						ttisgmts[mrudst]);
+					isdsts[mrudst] = TRUE;
+					writetype[type] = TRUE;
 			}
-		puttzcode((long) ats[i], fp);
-	}
-	if (timecnt > 0)
-		(void) fwrite((void *) types, (size_t) sizeof types[0],
-			(size_t) timecnt, fp);
-	for (i = 0; i < typecnt; ++i) {
-		puttzcode((long) gmtoffs[i], fp);
-		(void) putc(isdsts[i], fp);
-		(void) putc(abbrinds[i], fp);
-	}
-	if (charcnt != 0)
-		(void) fwrite((void *) chars, (size_t) sizeof chars[0],
-			(size_t) charcnt, fp);
-	for (i = 0; i < leapcnt; ++i) {
-		if (roll[i]) {
-			if (timecnt == 0 || trans[i] < ats[0]) {
-				j = 0;
-				while (isdsts[j])
-					if (++j >= typecnt) {
-						j = 0;
-						break;
-					}
-			} else {
-				j = 1;
-				while (j < timecnt && trans[i] >= ats[j])
-					++j;
-				j = types[j - 1];
+			if (histd >= 0 && mrustd >= 0 && histd != mrustd &&
+				gmtoffs[histd] != gmtoffs[mrustd]) {
+					isdsts[mrustd] = -1;
+					type = addtype(gmtoffs[mrustd],
+						&chars[abbrinds[mrustd]],
+						FALSE,
+						ttisstds[mrustd],
+						ttisgmts[mrustd]);
+					isdsts[mrustd] = FALSE;
+					writetype[type] = TRUE;
 			}
-			puttzcode((long) tadd(trans[i], -gmtoffs[j]), fp);
-		} else	puttzcode((long) trans[i], fp);
-		puttzcode((long) corr[i], fp);
-	}
-	for (i = 0; i < typecnt; ++i)
-		(void) putc(ttisstds[i], fp);
-	for (i = 0; i < typecnt; ++i)
-		(void) putc(ttisgmts[i], fp);
+		}
+#endif /* !defined LEAVE_SOME_PRE_2011_SYSTEMS_IN_THE_LURCH */
+		thistypecnt = 0;
+		for (i = 0; i < typecnt; ++i)
+			typemap[i] = writetype[i] ?  thistypecnt++ : -1;
+		for (i = 0; i < sizeof indmap / sizeof indmap[0]; ++i)
+			indmap[i] = -1;
+		thischarcnt = 0;
+		for (i = 0; i < typecnt; ++i) {
+			register char *	thisabbr;
+
+			if (!writetype[i])
+				continue;
+			if (indmap[abbrinds[i]] >= 0)
+				continue;
+			thisabbr = &chars[abbrinds[i]];
+			for (j = 0; j < thischarcnt; ++j)
+				if (strcmp(&thischars[j], thisabbr) == 0)
+					break;
+			if (j == thischarcnt) {
+				(void) strcpy(&thischars[(int) thischarcnt],
+					thisabbr);
+				thischarcnt += strlen(thisabbr) + 1;
+			}
+			indmap[abbrinds[i]] = j;
+		}
+#define DO(field)	(void) fwrite((void *) tzh.field, \
+				(size_t) sizeof tzh.field, (size_t) 1, fp)
+		tzh = tzh0;
+		(void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+		tzh.tzh_version[0] = ZIC_VERSION;
+		convert(eitol(thistypecnt), tzh.tzh_ttisgmtcnt);
+		convert(eitol(thistypecnt), tzh.tzh_ttisstdcnt);
+		convert(eitol(thisleapcnt), tzh.tzh_leapcnt);
+		convert(eitol(thistimecnt), tzh.tzh_timecnt);
+		convert(eitol(thistypecnt), tzh.tzh_typecnt);
+		convert(eitol(thischarcnt), tzh.tzh_charcnt);
+		DO(tzh_magic);
+		DO(tzh_version);
+		DO(tzh_reserved);
+		DO(tzh_ttisgmtcnt);
+		DO(tzh_ttisstdcnt);
+		DO(tzh_leapcnt);
+		DO(tzh_timecnt);
+		DO(tzh_typecnt);
+		DO(tzh_charcnt);
+#undef DO
+		for (i = thistimei; i < thistimelim; ++i)
+			if (pass == 1)
+				puttzcode((long) ats[i], fp);
+			else	puttzcode64(ats[i], fp);
+		for (i = thistimei; i < thistimelim; ++i) {
+			unsigned char	uc;
+
+			uc = typemap[types[i]];
+			(void) fwrite((void *) &uc,
+				(size_t) sizeof uc,
+				(size_t) 1,
+				fp);
+		}
+		for (i = 0; i < typecnt; ++i)
+			if (writetype[i]) {
+				puttzcode(gmtoffs[i], fp);
+				(void) putc(isdsts[i], fp);
+				(void) putc((unsigned char) indmap[abbrinds[i]], fp);
+			}
+		if (thischarcnt != 0)
+			(void) fwrite((void *) thischars,
+				(size_t) sizeof thischars[0],
+				(size_t) thischarcnt, fp);
+		for (i = thisleapi; i < thisleaplim; ++i) {
+			register zic_t	todo;
+
+			if (roll[i]) {
+				if (timecnt == 0 || trans[i] < ats[0]) {
+					j = 0;
+					while (isdsts[j])
+						if (++j >= typecnt) {
+							j = 0;
+							break;
+						}
+				} else {
+					j = 1;
+					while (j < timecnt &&
+						trans[i] >= ats[j])
+							++j;
+					j = types[j - 1];
+				}
+				todo = tadd(trans[i], -gmtoffs[j]);
+			} else	todo = trans[i];
+			if (pass == 1)
+				puttzcode((long) todo, fp);
+			else	puttzcode64(todo, fp);
+			puttzcode(corr[i], fp);
+		}
+		for (i = 0; i < typecnt; ++i)
+			if (writetype[i])
+				(void) putc(ttisstds[i], fp);
+		for (i = 0; i < typecnt; ++i)
+			if (writetype[i])
+				(void) putc(ttisgmts[i], fp);
+	}
+	(void) fprintf(fp, "\n%s\n", string);
 	if (ferror(fp) || fclose(fp))
 		errx(EXIT_FAILURE, _("error writing %s"), fullname);
 	if (chmod(fullname, mflag) < 0)
@@ -1537,21 +1748,223 @@ const char * const	name;
 }
 
 static void
-doabbr(abbr, format, letters, isdst)
+doabbr(abbr, format, letters, isdst, doquotes)
 char * const		abbr;
 const char * const	format;
 const char * const	letters;
 const int		isdst;
+const int		doquotes;
 {
-	if (strchr(format, '/') == NULL) {
+	register char *	cp;
+	register char *	slashp;
+	register int	len;
+
+	slashp = strchr(format, '/');
+	if (slashp == NULL) {
 		if (letters == NULL)
 			(void) strcpy(abbr, format);
 		else	(void) sprintf(abbr, format, letters);
-	} else if (isdst)
-		(void) strcpy(abbr, strchr(format, '/') + 1);
-	else {
-		(void) strcpy(abbr, format);
-		*strchr(abbr, '/') = '\0';
+	} else if (isdst) {
+		(void) strcpy(abbr, slashp + 1);
+	} else {
+		if (slashp > format)
+			(void) strncpy(abbr, format,
+				(unsigned) (slashp - format));
+		abbr[slashp - format] = '\0';
+	}
+	if (!doquotes)
+		return;
+	for (cp = abbr; *cp != '\0'; ++cp)
+		if (strchr("ABCDEFGHIJKLMNOPQRSTUVWXYZ", *cp) == NULL &&
+			strchr("abcdefghijklmnopqrstuvwxyz", *cp) == NULL)
+				break;
+	len = strlen(abbr);
+	if (len > 0 && *cp == '\0')
+		return;
+	abbr[len + 2] = '\0';
+	abbr[len + 1] = '>';
+	for ( ; len > 0; --len)
+		abbr[len] = abbr[len - 1];
+	abbr[0] = '<';
+}
+
+static void
+updateminmax(x)
+const int	x;
+{
+	if (min_year > x)
+		min_year = x;
+	if (max_year < x)
+		max_year = x;
+}
+
+static int
+stringoffset(result, offset)
+char *	result;
+long	offset;
+{
+	register int	hours;
+	register int	minutes;
+	register int	seconds;
+
+	result[0] = '\0';
+	if (offset < 0) {
+		(void) strcpy(result, "-");
+		offset = -offset;
+	}
+	seconds = offset % SECSPERMIN;
+	offset /= SECSPERMIN;
+	minutes = offset % MINSPERHOUR;
+	offset /= MINSPERHOUR;
+	hours = offset;
+	if (hours >= HOURSPERDAY) {
+		result[0] = '\0';
+		return -1;
+	}
+	(void) sprintf(end(result), "%d", hours);
+	if (minutes != 0 || seconds != 0) {
+		(void) sprintf(end(result), ":%02d", minutes);
+		if (seconds != 0)
+			(void) sprintf(end(result), ":%02d", seconds);
+	}
+	return 0;
+}
+
+static int
+stringrule(result, rp, dstoff, gmtoff)
+char *				result;
+const struct rule * const	rp;
+const long			dstoff;
+const long			gmtoff;
+{
+	register long	tod;
+
+	result = end(result);
+	if (rp->r_dycode == DC_DOM) {
+		register int	month, total;
+
+		if (rp->r_dayofmonth == 29 && rp->r_month == TM_FEBRUARY)
+			return -1;
+		total = 0;
+		for (month = 0; month < rp->r_month; ++month)
+			total += len_months[0][month];
+		(void) sprintf(result, "J%d", total + rp->r_dayofmonth);
+	} else {
+		register int	week;
+
+		if (rp->r_dycode == DC_DOWGEQ) {
+			week = 1 + rp->r_dayofmonth / DAYSPERWEEK;
+			if ((week - 1) * DAYSPERWEEK + 1 != rp->r_dayofmonth)
+				return -1;
+		} else if (rp->r_dycode == DC_DOWLEQ) {
+			if (rp->r_dayofmonth == len_months[1][rp->r_month])
+				week = 5;
+			else {
+				week = 1 + rp->r_dayofmonth / DAYSPERWEEK;
+				if (week * DAYSPERWEEK - 1 != rp->r_dayofmonth)
+					return -1;
+			}
+		} else	return -1;	/* "cannot happen" */
+		(void) sprintf(result, "M%d.%d.%d",
+			rp->r_month + 1, week, rp->r_wday);
+	}
+	tod = rp->r_tod;
+	if (rp->r_todisgmt)
+		tod += gmtoff;
+	if (rp->r_todisstd && rp->r_stdoff == 0)
+		tod += dstoff;
+	if (tod < 0) {
+		result[0] = '\0';
+		return -1;
+	}
+	if (tod != 2 * SECSPERMIN * MINSPERHOUR) {
+		(void) strcat(result, "/");
+		if (stringoffset(end(result), tod) != 0)
+			return -1;
+	}
+	return 0;
+}
+
+static void
+stringzone(result, zpfirst, zonecount)
+char *				result;
+const struct zone * const	zpfirst;
+const int			zonecount;
+{
+	register const struct zone *	zp;
+	register struct rule *		rp;
+	register struct rule *		stdrp;
+	register struct rule *		dstrp;
+	register int			i;
+	register const char *		abbrvar;
+
+	result[0] = '\0';
+	zp = zpfirst + zonecount - 1;
+	stdrp = dstrp = NULL;
+	for (i = 0; i < zp->z_nrules; ++i) {
+		rp = &zp->z_rules[i];
+		if (rp->r_hiwasnum || rp->r_hiyear != INT_MAX)
+			continue;
+		if (rp->r_yrtype != NULL)
+			continue;
+		if (rp->r_stdoff == 0) {
+			if (stdrp == NULL)
+				stdrp = rp;
+			else	return;
+		} else {
+			if (dstrp == NULL)
+				dstrp = rp;
+			else	return;
+		}
+	}
+	if (stdrp == NULL && dstrp == NULL) {
+		/*
+		** There are no rules running through "max".
+		** Let's find the latest rule.
+		*/
+		for (i = 0; i < zp->z_nrules; ++i) {
+			rp = &zp->z_rules[i];
+			if (stdrp == NULL || rp->r_hiyear > stdrp->r_hiyear ||
+				(rp->r_hiyear == stdrp->r_hiyear &&
+				rp->r_month > stdrp->r_month))
+					stdrp = rp;
+		}
+		if (stdrp != NULL && stdrp->r_stdoff != 0)
+			return;	/* We end up in DST (a POSIX no-no). */
+		/*
+		** Horrid special case: if year is 2037,
+		** presume this is a zone handled on a year-by-year basis;
+		** do not try to apply a rule to the zone.
+		*/
+		if (stdrp != NULL && stdrp->r_hiyear == 2037)
+			return;
+	}
+	if (stdrp == NULL && (zp->z_nrules != 0 || zp->z_stdoff != 0))
+		return;
+	abbrvar = (stdrp == NULL) ? "" : stdrp->r_abbrvar;
+	doabbr(result, zp->z_format, abbrvar, FALSE, TRUE);
+	if (stringoffset(end(result), -zp->z_gmtoff) != 0) {
+		result[0] = '\0';
+		return;
+	}
+	if (dstrp == NULL)
+		return;
+	doabbr(end(result), zp->z_format, dstrp->r_abbrvar, TRUE, TRUE);
+	if (dstrp->r_stdoff != SECSPERMIN * MINSPERHOUR)
+		if (stringoffset(end(result),
+			-(zp->z_gmtoff + dstrp->r_stdoff)) != 0) {
+				result[0] = '\0';
+				return;
+		}
+	(void) strcat(result, ",");
+	if (stringrule(result, dstrp, dstrp->r_stdoff, zp->z_gmtoff) != 0) {
+		result[0] = '\0';
+		return;
+	}
+	(void) strcat(result, ",");
+	if (stringrule(result, stdrp, dstrp->r_stdoff, zp->z_gmtoff) != 0) {
+		result[0] = '\0';
+		return;
 	}
 }
 
@@ -1564,7 +1977,7 @@ const int			zonecount;
 	register struct rule *		rp;
 	register int			i, j;
 	register int			usestart, useuntil;
-	register time_t			starttime, untiltime;
+	register zic_t			starttime, untiltime;
 	register long			gmtoff;
 	register long			stdoff;
 	register int			year;
@@ -1572,8 +1985,17 @@ const int			zonecount;
 	register int			startttisstd;
 	register int			startttisgmt;
 	register int			type;
-	char				startbuf[BUFSIZ];
-
+	register char *			startbuf;
+	register char *			ab;
+	register char *			envvar;
+	register int			max_abbr_len;
+	register int			max_envvar_len;
+
+	max_abbr_len = 2 + max_format_len + max_abbrvar_len;
+	max_envvar_len = 2 * max_abbr_len + 5 * 9;
+	startbuf = emalloc(max_abbr_len + 1);
+	ab = emalloc(max_abbr_len + 1);
+	envvar = emalloc(max_envvar_len + 1);
 	INITIALIZE(untiltime);
 	INITIALIZE(starttime);
 	/*
@@ -1583,11 +2005,57 @@ const int			zonecount;
 	typecnt = 0;
 	charcnt = 0;
 	/*
-	** Thanks to Earl Chew (earl@dnd.icp.nec.com.au)
+	** Thanks to Earl Chew
 	** for noting the need to unconditionally initialize startttisstd.
 	*/
 	startttisstd = FALSE;
 	startttisgmt = FALSE;
+	min_year = max_year = EPOCH_YEAR;
+	if (leapseen) {
+		updateminmax(leapminyear);
+		updateminmax(leapmaxyear + (leapmaxyear < INT_MAX));
+	}
+	for (i = 0; i < zonecount; ++i) {
+		zp = &zpfirst[i];
+		if (i < zonecount - 1)
+			updateminmax(zp->z_untilrule.r_loyear);
+		for (j = 0; j < zp->z_nrules; ++j) {
+			rp = &zp->z_rules[j];
+			if (rp->r_lowasnum)
+				updateminmax(rp->r_loyear);
+			if (rp->r_hiwasnum)
+				updateminmax(rp->r_hiyear);
+		}
+	}
+	/*
+	** Generate lots of data if a rule can't cover all future times.
+	*/
+	stringzone(envvar, zpfirst, zonecount);
+	if (noise && envvar[0] == '\0') {
+		register char *	wp;
+
+wp = ecpyalloc(_("no POSIX environment variable for zone"));
+		wp = ecatalloc(wp, " ");
+		wp = ecatalloc(wp, zpfirst->z_name);
+		warning(wp);
+		ifree(wp);
+	}
+	if (envvar[0] == '\0') {
+		if (min_year >= INT_MIN + YEARSPERREPEAT)
+			min_year -= YEARSPERREPEAT;
+		else	min_year = INT_MIN;
+		if (max_year <= INT_MAX - YEARSPERREPEAT)
+			max_year += YEARSPERREPEAT;
+		else	max_year = INT_MAX;
+	}
+	/*
+	** For the benefit of older systems,
+	** generate data from 1900 through 2037.
+	*/
+	if (min_year > 1900)
+		min_year = 1900;
+	if (max_year < 2037)
+		max_year = 2037;
 	for (i = 0; i < zonecount; ++i) {
 		/*
 		** A guess that may well be corrected later.
@@ -1605,7 +2073,7 @@ const int			zonecount;
 		if (zp->z_nrules == 0) {
 			stdoff = zp->z_stdoff;
 			doabbr(startbuf, zp->z_format,
-				(char *) NULL, stdoff != 0);
+				(char *) NULL, stdoff != 0, FALSE);
 			type = addtype(oadd(zp->z_gmtoff, stdoff),
 				startbuf, stdoff != 0, startttisstd,
 				startttisgmt);
@@ -1633,9 +2101,8 @@ const int			zonecount;
 			}
 			for ( ; ; ) {
 				register int	k;
-				register time_t	jtime, ktime;
+				register zic_t	jtime, ktime;
 				register long	offset;
-				char		buf[BUFSIZ];
 
 				INITIALIZE(ktime);
 				if (useuntil) {
@@ -1691,23 +2158,27 @@ const int			zonecount;
 							stdoff);
 						doabbr(startbuf, zp->z_format,
 							rp->r_abbrvar,
-							rp->r_stdoff != 0);
+							rp->r_stdoff != 0,
+							FALSE);
 						continue;
 					}
 					if (*startbuf == '\0' &&
-					    startoff == oadd(zp->z_gmtoff,
-					    stdoff)) {
-						doabbr(startbuf, zp->z_format,
-							rp->r_abbrvar,
-							rp->r_stdoff != 0);
+						startoff == oadd(zp->z_gmtoff,
+						stdoff)) {
+							doabbr(startbuf,
+								zp->z_format,
+								rp->r_abbrvar,
+								rp->r_stdoff !=
+								0,
+								FALSE);
 					}
 				}
 				eats(zp->z_filename, zp->z_linenum,
 					rp->r_filename, rp->r_linenum);
-				doabbr(buf, zp->z_format, rp->r_abbrvar,
-					rp->r_stdoff != 0);
+				doabbr(ab, zp->z_format, rp->r_abbrvar,
+					rp->r_stdoff != 0, FALSE);
 				offset = oadd(zp->z_gmtoff, rp->r_stdoff);
-				type = addtype(offset, buf, rp->r_stdoff != 0,
+				type = addtype(offset, ab, rp->r_stdoff != 0,
 					rp->r_todisstd, rp->r_todisgmt);
 				addtt(ktime, type);
 			}
@@ -1740,12 +2211,15 @@ error(_("can't determine time zone abbreviation to use just after until time"));
 				starttime = tadd(starttime, -gmtoff);
 		}
 	}
-	writezone(zpfirst->z_name);
+	writezone(zpfirst->z_name, envvar);
+	ifree(startbuf);
+	ifree(ab);
+	ifree(envvar);
 }
 
 static void
 addtt(starttime, type)
-const time_t	starttime;
+const zic_t	starttime;
 int		type;
 {
 	if (starttime <= min_time ||
@@ -1764,7 +2238,7 @@ int		type;
 	}
 	if (timecnt >= TZ_MAX_TIMES) {
 		error(_("too many transitions?!"));
-		(void) exit(EXIT_FAILURE);
+		exit(EXIT_FAILURE);
 	}
 	attypes[timecnt].at = starttime;
 	attypes[timecnt].type = type;
@@ -1783,15 +2257,15 @@ const int		ttisgmt;
 
 	if (isdst != TRUE && isdst != FALSE) {
 		error(_("internal error - addtype called with bad isdst"));
-		(void) exit(EXIT_FAILURE);
+		exit(EXIT_FAILURE);
 	}
 	if (ttisstd != TRUE && ttisstd != FALSE) {
 		error(_("internal error - addtype called with bad ttisstd"));
-		(void) exit(EXIT_FAILURE);
+		exit(EXIT_FAILURE);
 	}
 	if (ttisgmt != TRUE && ttisgmt != FALSE) {
 		error(_("internal error - addtype called with bad ttisgmt"));
-		(void) exit(EXIT_FAILURE);
+		exit(EXIT_FAILURE);
 	}
 	/*
 	** See if there's already an entry for this zone type.
@@ -1810,7 +2284,11 @@ const int		ttisgmt;
 	*/
 	if (typecnt >= TZ_MAX_TYPES) {
 		error(_("too many local time types"));
-		(void) exit(EXIT_FAILURE);
+		exit(EXIT_FAILURE);
+	}
+	if (! (-1L - 2147483647L <= gmtoff && gmtoff <= 2147483647L)) {
+		error(_("UTC offset out of range"));
+		exit(EXIT_FAILURE);
 	}
 	gmtoffs[i] = gmtoff;
 	isdsts[i] = isdst;
@@ -1829,7 +2307,7 @@ const int		ttisgmt;
 
 static void
 leapadd(t, positive, rolling, count)
-const time_t	t;
+const zic_t	t;
 const int	positive;
 const int	rolling;
 int		count;
@@ -1838,13 +2316,13 @@ int		count;
 
 	if (leapcnt + (positive ? count : 1) > TZ_MAX_LEAPS) {
 		error(_("too many leap seconds"));
-		(void) exit(EXIT_FAILURE);
+		exit(EXIT_FAILURE);
 	}
 	for (i = 0; i < leapcnt; ++i)
 		if (t <= trans[i]) {
 			if (t == trans[i]) {
 				error(_("repeated leap second moment"));
-				(void) exit(EXIT_FAILURE);
+				exit(EXIT_FAILURE);
 			}
 			break;
 		}
@@ -1862,7 +2340,7 @@ int		count;
 }
 
 static void
-adjleap P((void))
+adjleap(void)
 {
 	register int	i;
 	register long	last = 0;
@@ -1898,7 +2376,7 @@ const char * const	type;
 	error(_("wild result from command execution"));
 	warnx(_("command was '%s', result was %d"), buf, result);
 	for ( ; ; )
-		(void) exit(EXIT_FAILURE);
+		exit(EXIT_FAILURE);
 }
 
 static int
@@ -1979,8 +2457,9 @@ register char *	cp;
 		emalloc((int) ((strlen(cp) + 1) * sizeof *array));
 	nsubs = 0;
 	for ( ; ; ) {
-		while (isascii(*cp) && isspace((unsigned char) *cp))
-			++cp;
+		while (isascii((unsigned char) *cp) &&
+			isspace((unsigned char) *cp))
+				++cp;
 		if (*cp == '\0' || *cp == '#')
 			break;
 		array[nsubs++] = dp = cp;
@@ -1990,7 +2469,10 @@ register char *	cp;
 			else while ((*dp = *cp++) != '"')
 				if (*dp != '\0')
 					++dp;
-				else	error(_("odd number of quotation marks"));
+				else {
+					error(_("odd number of quotation marks"));
+					exit(EXIT_FAILURE);
+				}
 		} while (*cp != '\0' && *cp != '#' &&
 			(!isascii(*cp) || !isspace((unsigned char) *cp)));
 		if (isascii(*cp) && isspace((unsigned char) *cp))
@@ -2011,17 +2493,17 @@ const long	t2;
 	t = t1 + t2;
 	if ((t2 > 0 && t <= t1) || (t2 < 0 && t >= t1)) {
 		error(_("time overflow"));
-		(void) exit(EXIT_FAILURE);
+		exit(EXIT_FAILURE);
 	}
 	return t;
 }
 
-static time_t
+static zic_t
 tadd(t1, t2)
-const time_t	t1;
+const zic_t	t1;
 const long	t2;
 {
-	register time_t	t;
+	register zic_t	t;
 
 	if (t1 == max_time && t2 > 0)
 		return max_time;
@@ -2030,7 +2512,7 @@ const long	t2;
 	t = t1 + t2;
 	if ((t2 > 0 && t <= t1) || (t2 < 0 && t >= t1)) {
 		error(_("time overflow"));
-		(void) exit(EXIT_FAILURE);
+		exit(EXIT_FAILURE);
 	}
 	return t;
 }
@@ -2040,14 +2522,14 @@ const long	t2;
 ** 1970, 00:00 LOCAL time - in that year that the rule refers to.
 */
 
-static time_t
+static zic_t
 rpytime(rp, wantedy)
 register const struct rule * const	rp;
 register const int			wantedy;
 {
 	register int	y, m, i;
 	register long	dayoff;			/* with a nod to Margaret O. */
-	register time_t	t;
+	register zic_t	t;
 
 	if (wantedy == INT_MIN)
 		return min_time;
@@ -2077,7 +2559,7 @@ register const int			wantedy;
 			--i;
 		else {
 			error(_("use of 2/29 in non leap-year"));
-			(void) exit(EXIT_FAILURE);
+			exit(EXIT_FAILURE);
 		}
 	}
 	--i;
@@ -2111,16 +2593,15 @@ register const int			wantedy;
 			}
 		if (i < 0 || i >= len_months[isleap(y)][m]) {
 			if (noise)
-				warning(_("rule goes past start/end of month--will not work with pre-2004 versions of zic"));
+				warning(_("rule goes past start/end of month--\
+will not work with pre-2004 versions of zic"));
 		}
 	}
-	if (dayoff < 0 && !TYPE_SIGNED(time_t))
-		return min_time;
 	if (dayoff < min_time / SECSPERDAY)
 		return min_time;
 	if (dayoff > max_time / SECSPERDAY)
 		return max_time;
-	t = (time_t) dayoff * SECSPERDAY;
+	t = (zic_t) dayoff * SECSPERDAY;
 	return tadd(t, rp->r_tod);
 }
 
@@ -2130,10 +2611,48 @@ const char * const	string;
 {
 	register int	i;
 
+	if (strcmp(string, GRANDPARENTED) != 0) {
+		register const char *	cp;
+		register char *		wp;
+
+		/*
+		** Want one to ZIC_MAX_ABBR_LEN_WO_WARN alphabetics
+		** optionally followed by a + or - and a number from 1 to 14.
+		*/
+		cp = string;
+		wp = NULL;
+		while (isascii((unsigned char) *cp) &&
+			isalpha((unsigned char) *cp))
+				++cp;
+		if (cp - string == 0)
+wp = _("time zone abbreviation lacks alphabetic at start");
+		if (noise && cp - string > 3)
+wp = _("time zone abbreviation has more than 3 alphabetics");
+		if (cp - string > ZIC_MAX_ABBR_LEN_WO_WARN)
+wp = _("time zone abbreviation has too many alphabetics");
+		if (wp == NULL && (*cp == '+' || *cp == '-')) {
+			++cp;
+			if (isascii((unsigned char) *cp) &&
+				isdigit((unsigned char) *cp))
+					if (*cp++ == '1' &&
+						*cp >= '0' && *cp <= '4')
+							++cp;
+		}
+		if (*cp != '\0')
+wp = _("time zone abbreviation differs from POSIX standard");
+		if (wp != NULL) {
+			wp = ecpyalloc(wp);
+			wp = ecatalloc(wp, " (");
+			wp = ecatalloc(wp, string);
+			wp = ecatalloc(wp, ")");
+			warning(wp);
+			ifree(wp);
+		}
+	}
 	i = strlen(string) + 1;
 	if (charcnt + i > TZ_MAX_CHARS) {
 		error(_("too many, or too long, time zone abbreviations"));
-		(void) exit(EXIT_FAILURE);
+		exit(EXIT_FAILURE);
 	}
 	(void) strcpy(&chars[charcnt], string);
 	charcnt += eitol(i);
@@ -2141,7 +2660,7 @@ const char * const	string;
 
 static int
 mkdirs(argname)
-char * const	argname;
+char *		argname;
 {
 	register char *	name;
 	register char *	cp;