[apple/system_cmds.git] / zdump.tproj / zdump.c

/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * "Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
 * Reserved.  This file contains Original Code and/or Modifications of
 * Original Code as defined in and that are subject to the Apple Public
 * Source License Version 1.0 (the 'License').  You may not use this file
 * except in compliance with the License.  Please obtain a copy of the
 * License at http://www.apple.com/publicsource and read it before using
 * this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License."
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char	elsieid[] = "@(#)zdump.c	7.24";
#else
static char rcsid[] = "$OpenBSD: zdump.c,v 1.5 1997/01/21 04:52:45 millert Exp $";
#endif
#endif /* LIBC_SCCS and not lint */

/*
** 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.
*/

#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 */

#ifndef MAX_STRING_LENGTH
#define MAX_STRING_LENGTH	1024
#endif /* !defined MAX_STRING_LENGTH */

#ifndef TRUE
#define TRUE		1
#endif /* !defined TRUE */

#ifndef FALSE
#define FALSE		0
#endif /* !defined FALSE */

#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 */

#if HAVE_GETTEXT - 0
#include "locale.h"	/* for setlocale */
#include "libintl.h"
#endif /* HAVE_GETTEXT - 0 */

#ifndef GNUC_or_lint
#ifdef lint
#define GNUC_or_lint
#endif /* defined lint */
#ifndef lint
#ifdef __GNUC__
#define GNUC_or_lint
#endif /* defined __GNUC__ */
#endif /* !defined lint */
#endif /* !defined GNUC_or_lint */

#ifndef INITIALIZE
#ifdef GNUC_or_lint
#define INITIALIZE(x)	((x) = 0)
#endif /* defined GNUC_or_lint */
#ifndef GNUC_or_lint
#define INITIALIZE(x)
#endif /* !defined GNUC_or_lint */
#endif /* !defined INITIALIZE */

/*
** 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 - 0
#define _(msgid) gettext(msgid)
#else /* !(HAVE_GETTEXT - 0) */
#define _(msgid) msgid
#endif /* !(HAVE_GETTEXT - 0) */
#endif /* !defined _ */

#ifndef TZ_DOMAIN
#define TZ_DOMAIN "tz"
#endif /* !defined TZ_DOMAIN */

extern char **	environ;
extern int	getopt();
extern char *	optarg;
extern int	optind;
extern time_t	time();
extern char *	tzname[2];

static char *	abbr();
static long	delta();
static time_t	hunt();
static int	longest;
static char *	progname;
static void	show();

int
main(argc, argv)
int	argc;
char *	argv[];
{
	register int		i;
	register int		c;
	register int		vflag;
	register char *		cutoff;
	register int		cutyear;
	register long		cuttime;
	char **			fakeenv;
	time_t			now;
	time_t			t;
	time_t			newt;
	time_t			hibit;
	struct tm		tm;
	struct tm		newtm;

	INITIALIZE(cuttime);
#if HAVE_GETTEXT - 0
	(void) setlocale(LC_MESSAGES, "");
#ifdef TZ_DOMAINDIR
	(void) bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR);
#endif /* defined(TEXTDOMAINDIR) */
	(void) textdomain(TZ_DOMAIN);
#endif /* HAVE_GETTEXT - 0 */
	progname = argv[0];
	vflag = 0;
	cutoff = NULL;
	while ((c = getopt(argc, argv, "c:v")) == 'c' || c == 'v')
		if (c == 'v')
			vflag = 1;
		else	cutoff = optarg;
	if (c != EOF ||
		(optind == argc - 1 && strcmp(argv[optind], "=") == 0)) {
			(void) fprintf(stderr,
_("%s: usage is %s [ -v ] [ -c cutoff ] zonename ...\n"),
				argv[0], argv[0]);
			(void) exit(EXIT_FAILURE);
	}
	if (cutoff != NULL) {
		int	y;

		cutyear = atoi(cutoff);
		cuttime = 0;
		for (y = EPOCH_YEAR; y < cutyear; ++y)
			cuttime += DAYSPERNYEAR + isleap(y);
		cuttime *= SECSPERHOUR * HOURSPERDAY;
	}
	(void) time(&now);
	longest = 0;
	for (i = optind; i < argc; ++i)
		if (strlen(argv[i]) > longest)
			longest = strlen(argv[i]);
	for (hibit = 1; (hibit << 1) != 0; hibit <<= 1)
		continue;
	{
		register int	from;
		register int	to;

		for (i = 0;  environ[i] != NULL;  ++i)
			continue;
		fakeenv = (char **) malloc((size_t) ((i + 2) *
			sizeof *fakeenv));
		if (fakeenv == NULL ||
			(fakeenv[0] = (char *) malloc((size_t) (longest +
				4))) == NULL) {
					(void) perror(progname);
					(void) exit(EXIT_FAILURE);
		}
		to = 0;
		(void) strcpy(fakeenv[to++], "TZ=");
		for (from = 0; environ[from] != NULL; ++from)
			if (strncmp(environ[from], "TZ=", 3) != 0)
				fakeenv[to++] = environ[from];
		fakeenv[to] = NULL;
		environ = fakeenv;
	}
	for (i = optind; i < argc; ++i) {
		static char	buf[MAX_STRING_LENGTH];

		(void) strcpy(&fakeenv[0][3], argv[i]);
		show(argv[i], now, FALSE);
		if (!vflag)
			continue;
		/*
		** Get lowest value of t.
		*/
		t = hibit;
		if (t > 0)		/* time_t is unsigned */
			t = 0;
		show(argv[i], t, TRUE);
		t += SECSPERHOUR * HOURSPERDAY;
		show(argv[i], t, TRUE);
		tm = *localtime(&t);
		(void) strncpy(buf, abbr(&tm), (sizeof buf) - 1);
		for ( ; ; ) {
			if (cutoff != NULL && t >= cuttime)
				break;
			newt = t + SECSPERHOUR * 12;
			if (cutoff != NULL && newt >= cuttime)
				break;
			if (newt <= t)
				break;
			newtm = *localtime(&newt);
			if (delta(&newtm, &tm) != (newt - t) ||
				newtm.tm_isdst != tm.tm_isdst ||
				strcmp(abbr(&newtm), buf) != 0) {
					newt = hunt(argv[i], t, newt);
					newtm = *localtime(&newt);
					(void) strncpy(buf, abbr(&newtm),
						(sizeof buf) - 1);
			}
			t = newt;
			tm = newtm;
		}
		/*
		** Get highest value of t.
		*/
		t = ~((time_t) 0);
		if (t < 0)		/* time_t is signed */
			t &= ~hibit;
		t -= SECSPERHOUR * HOURSPERDAY;
		show(argv[i], t, TRUE);
		t += SECSPERHOUR * HOURSPERDAY;
		show(argv[i], t, TRUE);
	}
	if (fflush(stdout) || ferror(stdout)) {
		(void) fprintf(stderr, _("%s: Error writing standard output "),
			argv[0]);
		(void) perror(_("standard output"));
		(void) exit(EXIT_FAILURE);
	}
	exit(EXIT_SUCCESS);

	/* gcc -Wall pacifier */
	for ( ; ; )
		continue;
}

static time_t
hunt(name, lot, hit)
char *	name;
time_t	lot;
time_t	hit;
{
	time_t		t;
	struct tm	lotm;
	struct tm	tm;
	static char	loab[MAX_STRING_LENGTH];

	lotm = *localtime(&lot);
	(void) strncpy(loab, abbr(&lotm), (sizeof loab) - 1);
	loab[(sizeof loab) - 1] = '\0';
	while ((hit - lot) >= 2) {
		t = lot / 2 + hit / 2;
		if (t <= lot)
			++t;
		else if (t >= hit)
			--t;
		tm = *localtime(&t);
		if (delta(&tm, &lotm) == (t - lot) &&
			tm.tm_isdst == lotm.tm_isdst &&
			strcmp(abbr(&tm), loab) == 0) {
				lot = t;
				lotm = tm;
		} else	hit = t;
	}
	show(name, lot, TRUE);
	show(name, hit, TRUE);
	return hit;
}

/*
** Thanks to Paul Eggert (eggert@twinsun.com) for logic used in delta.
*/

static long
delta(newp, oldp)
struct tm *	newp;
struct tm *	oldp;
{
	long	result;
	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(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;
}

extern struct tm *	localtime();

static void
show(zone, t, v)
char *	zone;
time_t	t;
int	v;
{
	struct tm *	tmp;

	(void) printf("%-*s  ", longest, zone);
	if (v)
		(void) printf("%.24s GMT = ", asctime(gmtime(&t)));
	tmp = localtime(&t);
	(void) printf("%.24s", asctime(tmp));
	if (*abbr(tmp) != '\0')
		(void) printf(" %s", abbr(tmp));
	if (v) {
		(void) printf(" isdst=%d", tmp->tm_isdst);
#ifdef TM_GMTOFF
		(void) printf(" gmtoff=%ld", tmp->TM_GMTOFF);
#endif /* defined TM_GMTOFF */
	}
	(void) printf("\n");
}

static char *
abbr(tmp)
struct tm *	tmp;
{
	register char *	result;
	static char	nada;

	if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1)
		return &nada;
	result = tzname[tmp->tm_isdst];
	return (result == NULL) ? &nada : result;
}
Commit	Line	Data
1815bff5 A	1	/*
	2	* Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
20e66415 A	6	* "Portions Copyright (c) 1999 Apple Computer, Inc. All Rights
	7	* Reserved. This file contains Original Code and/or Modifications of
	8	* Original Code as defined in and that are subject to the Apple Public
	9	* Source License Version 1.0 (the 'License'). You may not use this file
	10	* except in compliance with the License. Please obtain a copy of the
	11	* License at http://www.apple.com/publicsource and read it before using
	12	* this file.
1815bff5 A	13	*
	14	* The Original Code and all software distributed under the License are
	15	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	16	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	17	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
20e66415 A	18	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	19	* License for the specific language governing rights and limitations
	20	* under the License."
1815bff5 A	21	*
	22	* @APPLE_LICENSE_HEADER_END@
	23	*/
	24	#if defined(LIBC_SCCS) && !defined(lint)
	25	#if 0
	26	static char elsieid[] = "@(#)zdump.c 7.24";
	27	#else
	28	static char rcsid[] = "$OpenBSD: zdump.c,v 1.5 1997/01/21 04:52:45 millert Exp $";
	29	#endif
	30	#endif /* LIBC_SCCS and not lint */
	31
	32	/*
	33	** This code has been made independent of the rest of the time
	34	** conversion package to increase confidence in the verification it provides.
	35	** You can use this code to help in verifying other implementations.
	36	*/
	37
	38	#include "stdio.h" /* for stdout, stderr, perror */
	39	#include "string.h" /* for strcpy */
	40	#include "sys/types.h" /* for time_t */
	41	#include "time.h" /* for struct tm */
	42	#include "stdlib.h" /* for exit, malloc, atoi */
	43
	44	#ifndef MAX_STRING_LENGTH
	45	#define MAX_STRING_LENGTH 1024
	46	#endif /* !defined MAX_STRING_LENGTH */
	47
	48	#ifndef TRUE
	49	#define TRUE 1
	50	#endif /* !defined TRUE */
	51
	52	#ifndef FALSE
	53	#define FALSE 0
	54	#endif /* !defined FALSE */
	55
	56	#ifndef EXIT_SUCCESS
	57	#define EXIT_SUCCESS 0
	58	#endif /* !defined EXIT_SUCCESS */
	59
	60	#ifndef EXIT_FAILURE
	61	#define EXIT_FAILURE 1
	62	#endif /* !defined EXIT_FAILURE */
	63
	64	#ifndef SECSPERMIN
	65	#define SECSPERMIN 60
	66	#endif /* !defined SECSPERMIN */
	67
	68	#ifndef MINSPERHOUR
	69	#define MINSPERHOUR 60
	70	#endif /* !defined MINSPERHOUR */
	71
	72	#ifndef SECSPERHOUR
	73	#define SECSPERHOUR (SECSPERMIN * MINSPERHOUR)
	74	#endif /* !defined SECSPERHOUR */
	75
	76	#ifndef HOURSPERDAY
	77	#define HOURSPERDAY 24
	78	#endif /* !defined HOURSPERDAY */
	79
	80	#ifndef EPOCH_YEAR
	81	#define EPOCH_YEAR 1970
	82	#endif /* !defined EPOCH_YEAR */
	83
	84	#ifndef TM_YEAR_BASE
85	#define TM_YEAR_BASE 1900
86	#endif /* !defined TM_YEAR_BASE */
87
88	#ifndef DAYSPERNYEAR
89	#define DAYSPERNYEAR 365
90	#endif /* !defined DAYSPERNYEAR */
91
92	#ifndef isleap
93	#define isleap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) \|\| ((y) % 400) == 0)
94	#endif /* !defined isleap */
95
96	#if HAVE_GETTEXT - 0
97	#include "locale.h" /* for setlocale */
98	#include "libintl.h"
99	#endif /* HAVE_GETTEXT - 0 */
100
101	#ifndef GNUC_or_lint
102	#ifdef lint
103	#define GNUC_or_lint
104	#endif /* defined lint */
105	#ifndef lint
106	#ifdef __GNUC__
107	#define GNUC_or_lint
108	#endif /* defined __GNUC__ */
109	#endif /* !defined lint */
110	#endif /* !defined GNUC_or_lint */
111
112	#ifndef INITIALIZE
113	#ifdef GNUC_or_lint
114	#define INITIALIZE(x) ((x) = 0)
115	#endif /* defined GNUC_or_lint */
116	#ifndef GNUC_or_lint
117	#define INITIALIZE(x)
118	#endif /* !defined GNUC_or_lint */
119	#endif /* !defined INITIALIZE */
120
121	/*
122	** For the benefit of GNU folk...
123	** `_(MSGID)' uses the current locale's message library string for MSGID.
124	** The default is to use gettext if available, and use MSGID otherwise.
125	*/
126
127	#ifndef _
128	#if HAVE_GETTEXT - 0
129	#define _(msgid) gettext(msgid)
130	#else /* !(HAVE_GETTEXT - 0) */
131	#define _(msgid) msgid
132	#endif /* !(HAVE_GETTEXT - 0) */
133	#endif /* !defined _ */
134
135	#ifndef TZ_DOMAIN
136	#define TZ_DOMAIN "tz"
137	#endif /* !defined TZ_DOMAIN */
138
139	extern char ** environ;
140	extern int getopt();
141	extern char * optarg;
142	extern int optind;
143	extern time_t time();
144	extern char * tzname[2];
145
146	static char * abbr();
147	static long delta();
148	static time_t hunt();
149	static int longest;
150	static char * progname;
151	static void show();
152
153	int
154	main(argc, argv)
155	int argc;
156	char * argv[];
157	{
158	register int i;
159	register int c;
160	register int vflag;
161	register char * cutoff;
162	register int cutyear;
163	register long cuttime;
164	char ** fakeenv;
165	time_t now;
166	time_t t;
167	time_t newt;
168	time_t hibit;
169	struct tm tm;
170	struct tm newtm;
171
172	INITIALIZE(cuttime);
173	#if HAVE_GETTEXT - 0
174	(void) setlocale(LC_MESSAGES, "");
175	#ifdef TZ_DOMAINDIR
176	(void) bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR);
177	#endif /* defined(TEXTDOMAINDIR) */
178	(void) textdomain(TZ_DOMAIN);
179	#endif /* HAVE_GETTEXT - 0 */
180	progname = argv[0];
181	vflag = 0;
182	cutoff = NULL;
183	while ((c = getopt(argc, argv, "c:v")) == 'c' \|\| c == 'v')
184	if (c == 'v')
185	vflag = 1;
186	else cutoff = optarg;
187	if (c != EOF \|\|
188	(optind == argc - 1 && strcmp(argv[optind], "=") == 0)) {
189	(void) fprintf(stderr,
190	_("%s: usage is %s [ -v ] [ -c cutoff ] zonename ...\n"),
191	argv[0], argv[0]);
192	(void) exit(EXIT_FAILURE);
193	}
194	if (cutoff != NULL) {
195	int y;
196
197	cutyear = atoi(cutoff);
198	cuttime = 0;
199	for (y = EPOCH_YEAR; y < cutyear; ++y)
200	cuttime += DAYSPERNYEAR + isleap(y);
201	cuttime = SECSPERHOUR HOURSPERDAY;
202	}
203	(void) time(&now);
204	longest = 0;
205	for (i = optind; i < argc; ++i)
206	if (strlen(argv[i]) > longest)
207	longest = strlen(argv[i]);
208	for (hibit = 1; (hibit << 1) != 0; hibit <<= 1)
209	continue;
210	{
211	register int from;
212	register int to;
213
214	for (i = 0; environ[i] != NULL; ++i)
215	continue;
216	fakeenv = (char *) malloc((size_t) ((i + 2)
217	sizeof *fakeenv));
218	if (fakeenv == NULL \|\|
219	(fakeenv[0] = (char *) malloc((size_t) (longest +
220	4))) == NULL) {
221	(void) perror(progname);
222	(void) exit(EXIT_FAILURE);
223	}
224	to = 0;
225	(void) strcpy(fakeenv[to++], "TZ=");
226	for (from = 0; environ[from] != NULL; ++from)
227	if (strncmp(environ[from], "TZ=", 3) != 0)
228	fakeenv[to++] = environ[from];
229	fakeenv[to] = NULL;
230	environ = fakeenv;
231	}
232	for (i = optind; i < argc; ++i) {
233	static char buf[MAX_STRING_LENGTH];
234
235	(void) strcpy(&fakeenv[0][3], argv[i]);
236	show(argv[i], now, FALSE);
237	if (!vflag)
238	continue;
239	/*
240	** Get lowest value of t.
241	*/
242	t = hibit;
243	if (t > 0) /* time_t is unsigned */
244	t = 0;
245	show(argv[i], t, TRUE);
246	t += SECSPERHOUR * HOURSPERDAY;
247	show(argv[i], t, TRUE);
248	tm = *localtime(&t);
249	(void) strncpy(buf, abbr(&tm), (sizeof buf) - 1);
250	for ( ; ; ) {
251	if (cutoff != NULL && t >= cuttime)
252	break;
253	newt = t + SECSPERHOUR * 12;
254	if (cutoff != NULL && newt >= cuttime)
255	break;
256	if (newt <= t)
257	break;
258	newtm = *localtime(&newt);
259	if (delta(&newtm, &tm) != (newt - t) \|\|
260	newtm.tm_isdst != tm.tm_isdst \|\|
261	strcmp(abbr(&newtm), buf) != 0) {
262	newt = hunt(argv[i], t, newt);
263	newtm = *localtime(&newt);
264	(void) strncpy(buf, abbr(&newtm),
265	(sizeof buf) - 1);
266	}
267	t = newt;
268	tm = newtm;
269	}
270	/*
271	** Get highest value of t.
272	*/
273	t = ~((time_t) 0);
274	if (t < 0) /* time_t is signed */
275	t &= ~hibit;
276	t -= SECSPERHOUR * HOURSPERDAY;
277	show(argv[i], t, TRUE);
278	t += SECSPERHOUR * HOURSPERDAY;
279	show(argv[i], t, TRUE);
280	}
281	if (fflush(stdout) \|\| ferror(stdout)) {
282	(void) fprintf(stderr, _("%s: Error writing standard output "),
283	argv[0]);
284	(void) perror(_("standard output"));
285	(void) exit(EXIT_FAILURE);
286	}
287	exit(EXIT_SUCCESS);
288
289	/* gcc -Wall pacifier */
290	for ( ; ; )
291	continue;
292	}
293
294	static time_t
295	hunt(name, lot, hit)
296	char * name;
297	time_t lot;
298	time_t hit;
299	{
300	time_t t;
301	struct tm lotm;
302	struct tm tm;
303	static char loab[MAX_STRING_LENGTH];
304
305	lotm = *localtime(&lot);
306	(void) strncpy(loab, abbr(&lotm), (sizeof loab) - 1);
307	loab[(sizeof loab) - 1] = '\0';
308	while ((hit - lot) >= 2) {
309	t = lot / 2 + hit / 2;
310	if (t <= lot)
311	++t;
312	else if (t >= hit)
313	--t;
314	tm = *localtime(&t);
315	if (delta(&tm, &lotm) == (t - lot) &&
316	tm.tm_isdst == lotm.tm_isdst &&
317	strcmp(abbr(&tm), loab) == 0) {
318	lot = t;
319	lotm = tm;
320	} else hit = t;
321	}
322	show(name, lot, TRUE);
323	show(name, hit, TRUE);
324	return hit;
325	}
326
327	/*
328	** Thanks to Paul Eggert (eggert@twinsun.com) for logic used in delta.
329	*/
330
331	static long
332	delta(newp, oldp)
333	struct tm * newp;
334	struct tm * oldp;
335	{
336	long result;
337	int tmy;
338
339	if (newp->tm_year < oldp->tm_year)
340	return -delta(oldp, newp);
341	result = 0;
342	for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy)
343	result += DAYSPERNYEAR + isleap(tmy + TM_YEAR_BASE);
344	result += newp->tm_yday - oldp->tm_yday;
345	result *= HOURSPERDAY;
346	result += newp->tm_hour - oldp->tm_hour;
347	result *= MINSPERHOUR;
348	result += newp->tm_min - oldp->tm_min;
349	result *= SECSPERMIN;
350	result += newp->tm_sec - oldp->tm_sec;
351	return result;
352	}
353
354	extern struct tm * localtime();
355
356	static void
357	show(zone, t, v)
358	char * zone;
359	time_t t;
360	int v;
361	{
362	struct tm * tmp;
363
364	(void) printf("%-*s ", longest, zone);
365	if (v)
366	(void) printf("%.24s GMT = ", asctime(gmtime(&t)));
367	tmp = localtime(&t);
368	(void) printf("%.24s", asctime(tmp));
369	if (*abbr(tmp) != '\0')
370	(void) printf(" %s", abbr(tmp));
371	if (v) {
372	(void) printf(" isdst=%d", tmp->tm_isdst);
373	#ifdef TM_GMTOFF
374	(void) printf(" gmtoff=%ld", tmp->TM_GMTOFF);
375	#endif /* defined TM_GMTOFF */
376	}
377	(void) printf("\n");
378	}
379
380	static char *
381	abbr(tmp)
382	struct tm * tmp;
383	{
384	register char * result;
385	static char nada;
386
387	if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1)
388	return &nada;
389	result = tzname[tmp->tm_isdst];
390	return (result == NULL) ? &nada : result;
391	}