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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.sbin/zdump/zdump.c	Lines:	0	219	0.0 %
Date:	2017-11-13	Branches:	0	167	0.0 %


/*	$OpenBSD: zdump.c,v 1.14 2016/03/15 19:50:48 millert Exp $ */
/*
** This file is in the public domain, so clarified as of
** 2009-05-17 by Arthur David Olson.
*/

/*
** 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 <ctype.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>

#define ZDUMP_LO_YEAR	(-500)
#define ZDUMP_HI_YEAR	2500

#define MAX_STRING_LENGTH	1024

#define TRUE		1
#define FALSE		0

#define SECSPERMIN	60
#define MINSPERHOUR	60
#define SECSPERHOUR	(SECSPERMIN * MINSPERHOUR)
#define HOURSPERDAY	24
#define EPOCH_YEAR	1970
#define TM_YEAR_BASE	1900
#define DAYSPERNYEAR	365

#define SECSPERDAY	((long) SECSPERHOUR * HOURSPERDAY)
#define SECSPERNYEAR	(SECSPERDAY * DAYSPERNYEAR)
#define SECSPERLYEAR	(SECSPERNYEAR + SECSPERDAY)

#define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))

#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 */

extern char	**environ;
extern char	*tzname[2];
extern char 	*__progname;

time_t		absolute_min_time;
time_t		absolute_max_time;
size_t		longest;
int		warned;

static char 		*abbr(struct tm *tmp);
static void		abbrok(const char *abbrp, const char *zone);
static long		delta(struct tm *newp, struct tm *oldp);
static void		dumptime(const struct tm *tmp);
static time_t		hunt(char *name, time_t lot, time_t	hit);
static void		setabsolutes(void);
static void		show(char *zone, time_t t, int v);
static const char 	*tformat(void);
static time_t		yeartot(long y);
static void		usage(void);

static void
abbrok(const char * const abbrp, const char * const zone)
{
	const char 	*cp;
	char 		*wp;

	if (warned)
		return;
	cp = abbrp;
	wp = NULL;
	while (isascii((unsigned char)*cp) &&
	    (isalnum((unsigned char)*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 = TRUE;
}

static void
usage(void)
{
	fprintf(stderr, "usage: %s [-v] [-c [loyear,]hiyear] zonename ...\n",
	    __progname);
	exit(EXIT_FAILURE);
}

int
main(int argc, char *argv[])
{
	int		i, c, vflag = 0;
	char		*cutarg = NULL;
	long		cutloyear = ZDUMP_LO_YEAR;
	long		cuthiyear = ZDUMP_HI_YEAR;
	time_t		cutlotime = 0, cuthitime = 0;
	time_t		now, t, newt;
	struct tm	tm, newtm, *tmp, *newtmp;
	char		**fakeenv;

	if (pledge("stdio rpath flock cpath wpath", NULL) == -1) {
		perror("pledge");
		exit(1);
	}

	while ((c = getopt(argc, argv, "c:v")) == 'c' || c == 'v') {
		switch (c) {
		case 'v':
			vflag = 1;
			break;
		case 'c':
			cutarg = optarg;
			break;
		default:
			usage();
			break;
		}
	}
	if (c != -1 ||
	    (optind == argc - 1 && strcmp(argv[optind], "=") == 0)) {
		usage();
	}
	if (vflag) {
		if (cutarg != NULL) {
			long	lo, hi;
			char	dummy;

			if (sscanf(cutarg, "%ld%c", &hi, &dummy) == 1) {
				cuthiyear = hi;
			} else if (sscanf(cutarg, "%ld,%ld%c",
			    &lo, &hi, &dummy) == 2) {
				cutloyear = lo;
				cuthiyear = hi;
			} else {
				fprintf(stderr, "%s: wild -c argument %s\n",
				    __progname, cutarg);
				exit(EXIT_FAILURE);
			}
		}
		setabsolutes();
		cutlotime = yeartot(cutloyear);
		cuthitime = yeartot(cuthiyear);
	}
	time(&now);
	longest = 0;
	for (i = optind; i < argc; ++i)
		if (strlen(argv[i]) > longest)
			longest = strlen(argv[i]);

	{
		int	from, to;

		for (i = 0; environ[i] != NULL; ++i)
			continue;
		fakeenv = reallocarray(NULL, i + 2, sizeof *fakeenv);
		if (fakeenv == NULL ||
		    (fakeenv[0] = malloc(longest + 4)) == NULL) {
			perror(__progname);
			exit(EXIT_FAILURE);
		}
		to = 0;
		strlcpy(fakeenv[to++], "TZ=", longest + 4);
		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) {
		char	buf[MAX_STRING_LENGTH];

		strlcpy(&fakeenv[0][3], argv[i], longest + 1);
		if (!vflag) {
			show(argv[i], now, FALSE);
			continue;
		}
		warned = FALSE;
		t = absolute_min_time;
		show(argv[i], t, TRUE);
		t += SECSPERHOUR * HOURSPERDAY;
		show(argv[i], t, TRUE);
		if (t < cutlotime)
			t = cutlotime;
		tmp = localtime(&t);
		if (tmp != NULL) {
			tm = *tmp;
			strlcpy(buf, abbr(&tm), sizeof buf);
		}
		for ( ; ; ) {
			if (t >= cuthitime || t >= cuthitime - SECSPERHOUR * 12)
				break;
			newt = t + SECSPERHOUR * 12;
			newtmp = localtime(&newt);
			if (newtmp != NULL)
				newtm = *newtmp;
			if ((tmp == NULL || newtmp == NULL) ? (tmp != newtmp) :
			    (delta(&newtm, &tm) != (newt - t) ||
			    newtm.tm_isdst != tm.tm_isdst ||
			    strcmp(abbr(&newtm), buf) != 0)) {
				newt = hunt(argv[i], t, newt);
				newtmp = localtime(&newt);
				if (newtmp != NULL) {
					newtm = *newtmp;
					strlcpy(buf, abbr(&newtm), sizeof buf);
				}
			}
			t = newt;
			tm = newtm;
			tmp = newtmp;
		}
		t = absolute_max_time;
		t -= SECSPERHOUR * HOURSPERDAY;
		show(argv[i], t, TRUE);
		t += SECSPERHOUR * HOURSPERDAY;
		show(argv[i], t, TRUE);
	}
	if (fflush(stdout) || ferror(stdout)) {
		fprintf(stderr, "%s: ", __progname);
		perror("Error writing to standard output");
		exit(EXIT_FAILURE);
	}
	return 0;
}

static void
setabsolutes(void)
{
	time_t t = 0, t1 = 1;

	while (t < t1) {
		t = t1;
		t1 = 2 * t1 + 1;
	}

	absolute_max_time = t;
	t = -t;
	absolute_min_time = t - 1;
	if (t < absolute_min_time)
		absolute_min_time = t;
}

static time_t
yeartot(const long y)
{
	long	myy = EPOCH_YEAR, seconds;
	time_t	t = 0;

	while (myy != y) {
		if (myy < y) {
			seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
			++myy;
			if (t > absolute_max_time - seconds) {
				t = absolute_max_time;
				break;
			}
			t += seconds;
		} else {
			--myy;
			seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
			if (t < absolute_min_time + seconds) {
				t = absolute_min_time;
				break;
			}
			t -= seconds;
		}
	}
	return t;
}

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

	lotmp = localtime(&lot);
	if (lotmp != NULL) {
		lotm = *lotmp;
		strlcpy(loab, abbr(&lotm), sizeof loab);
	}
	for ( ; ; ) {
		diff = (long) (hit - lot);
		if (diff < 2)
			break;
		t = lot;
		t += diff / 2;
		if (t <= lot)
			++t;
		else if (t >= hit)
			--t;
		tmp = localtime(&t);
		if (tmp != NULL)
			tm = *tmp;
		if ((lotmp == NULL || tmp == NULL) ? (lotmp == tmp) :
		    (delta(&tm, &lotm) == (t - lot) &&
		    tm.tm_isdst == lotm.tm_isdst &&
		    strcmp(abbr(&tm), loab) == 0)) {
			lot = t;
			lotm = tm;
			lotmp = tmp;
		} else
			hit = t;
	}
	show(name, lot, TRUE);
	show(name, hit, TRUE);
	return hit;
}

/*
** Thanks to Paul Eggert for logic used in delta.
*/

static long
delta(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_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;
}

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

	printf("%-*s  ", (int) longest, zone);
	if (v) {
		tmp = gmtime(&t);
		if (tmp == NULL) {
			printf(tformat(), t);
		} else {
			dumptime(tmp);
			printf(" UTC");
		}
		printf(" = ");
	}
	tmp = localtime(&t);
	dumptime(tmp);
	if (tmp != NULL) {
		if (*abbr(tmp) != '\0')
			printf(" %s", abbr(tmp));
		if (v) {
			printf(" isdst=%d", tmp->tm_isdst);
#ifdef TM_GMTOFF
			printf(" gmtoff=%ld", tmp->TM_GMTOFF);
#endif /* defined TM_GMTOFF */
		}
	}
	printf("\n");
	if (tmp != NULL && *abbr(tmp) != '\0')
		abbrok(abbr(tmp), zone);
}

static char *
abbr(struct tm *tmp)
{
	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;
}

/*
** 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)
{
	return "%lld";
}

static void
dumptime(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"
	};
	const char	*wn, *mn;
	int		lead, trail;

	if (timeptr == NULL) {
		printf("NULL");
		return;
	}
	/*
	** The packaged versions of localtime and gmtime 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));
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: zdump.c,v 1.14 2016/03/15 19:50:48 millert Exp $ */
2			/*
3			** This file is in the public domain, so clarified as of
4			** 2009-05-17 by Arthur David Olson.
5			*/
6
7			/*
8			** This code has been made independent of the rest of the time
9			** conversion package to increase confidence in the verification it provides.
10			** You can use this code to help in verifying other implementations.
11			*/
12
13			#include <ctype.h>
14			#include <stdio.h>
15			#include <string.h>
16			#include <stdlib.h>
17			#include <unistd.h>
18			#include <time.h>
19
20			#define ZDUMP_LO_YEAR (-500)
21			#define ZDUMP_HI_YEAR 2500
22
23			#define MAX_STRING_LENGTH 1024
24
25			#define TRUE 1
26			#define FALSE 0
27
28			#define SECSPERMIN 60
29			#define MINSPERHOUR 60
30			#define SECSPERHOUR (SECSPERMIN * MINSPERHOUR)
31			#define HOURSPERDAY 24
32			#define EPOCH_YEAR 1970
33			#define TM_YEAR_BASE 1900
34			#define DAYSPERNYEAR 365
35
36			#define SECSPERDAY ((long) SECSPERHOUR * HOURSPERDAY)
37			#define SECSPERNYEAR (SECSPERDAY * DAYSPERNYEAR)
38			#define SECSPERLYEAR (SECSPERNYEAR + SECSPERDAY)
39
40			#define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 \|\| ((y) % 400) == 0))
41
42			#ifndef isleap_sum
43			/*
44			** See tzfile.h for details on isleap_sum.
45			*/
46			#define isleap_sum(a, b) isleap((a) % 400 + (b) % 400)
47			#endif /* !defined isleap_sum */
48
49			extern char **environ;
50			extern char *tzname[2];
51			extern char *__progname;
52
53			time_t absolute_min_time;
54			time_t absolute_max_time;
55			size_t longest;
56			int warned;
57
58			static char abbr(struct tm tmp);
59			static void abbrok(const char abbrp, const char zone);
60			static long delta(struct tm newp, struct tm oldp);
61			static void dumptime(const struct tm *tmp);
62			static time_t hunt(char *name, time_t lot, time_t hit);
63			static void setabsolutes(void);
64			static void show(char *zone, time_t t, int v);
65			static const char *tformat(void);
66			static time_t yeartot(long y);
67			static void usage(void);
68
69			static void
70			abbrok(const char * const abbrp, const char * const zone)
71			{
72			const char *cp;
73			char *wp;
74
75			if (warned)
76			return;
77			cp = abbrp;
78			wp = NULL;
79			while (isascii((unsigned char)*cp) &&
80			(isalnum((unsigned char)cp) \|\| cp == '-' \|\| *cp == '+'))
81			++cp;
82			if (cp - abbrp < 3)
83			wp = "has fewer than 3 characters";
84			else if (cp - abbrp > 6)
85			wp = "has more than 6 characters";
86			else if (*cp)
87			wp = "has characters other than ASCII alphanumerics, '-' or '+'";
88			else
89			return;
90			fflush(stdout);
91			fprintf(stderr, "%s: warning: zone \"%s\" abbreviation \"%s\" %s\n",
92			__progname, zone, abbrp, wp);
93			warned = TRUE;
94			}
95
96			static void
97			usage(void)
98			{
99			fprintf(stderr, "usage: %s [-v] [-c [loyear,]hiyear] zonename ...\n",
100			__progname);
101			exit(EXIT_FAILURE);
102			}
103
104			int
105			main(int argc, char *argv[])
106			{
107			int i, c, vflag = 0;
108			char *cutarg = NULL;
109			long cutloyear = ZDUMP_LO_YEAR;
110			long cuthiyear = ZDUMP_HI_YEAR;
111			time_t cutlotime = 0, cuthitime = 0;
112			time_t now, t, newt;
113			struct tm tm, newtm, tmp, newtmp;
114			char **fakeenv;
115
116			if (pledge("stdio rpath flock cpath wpath", NULL) == -1) {
117			perror("pledge");
118			exit(1);
119			}
120
121			while ((c = getopt(argc, argv, "c:v")) == 'c' \|\| c == 'v') {
122			switch (c) {
123			case 'v':
124			vflag = 1;
125			break;
126			case 'c':
127			cutarg = optarg;
128			break;
129			default:
130			usage();
131			break;
132			}
133			}
134			if (c != -1 \|\|
135			(optind == argc - 1 && strcmp(argv[optind], "=") == 0)) {
136			usage();
137			}
138			if (vflag) {
139			if (cutarg != NULL) {
140			long lo, hi;
141			char dummy;
142
143			if (sscanf(cutarg, "%ld%c", &hi, &dummy) == 1) {
144			cuthiyear = hi;
145			} else if (sscanf(cutarg, "%ld,%ld%c",
146			&lo, &hi, &dummy) == 2) {
147			cutloyear = lo;
148			cuthiyear = hi;
149			} else {
150			fprintf(stderr, "%s: wild -c argument %s\n",
151			__progname, cutarg);
152			exit(EXIT_FAILURE);
153			}
154			}
155			setabsolutes();
156			cutlotime = yeartot(cutloyear);
157			cuthitime = yeartot(cuthiyear);
158			}
159			time(&now);
160			longest = 0;
161			for (i = optind; i < argc; ++i)
162			if (strlen(argv[i]) > longest)
163			longest = strlen(argv[i]);
164
165			{
166			int from, to;
167
168			for (i = 0; environ[i] != NULL; ++i)
169			continue;
170			fakeenv = reallocarray(NULL, i + 2, sizeof *fakeenv);
171			if (fakeenv == NULL \|\|
172			(fakeenv[0] = malloc(longest + 4)) == NULL) {
173			perror(__progname);
174			exit(EXIT_FAILURE);
175			}
176			to = 0;
177			strlcpy(fakeenv[to++], "TZ=", longest + 4);
178			for (from = 0; environ[from] != NULL; ++from)
179			if (strncmp(environ[from], "TZ=", 3) != 0)
180			fakeenv[to++] = environ[from];
181			fakeenv[to] = NULL;
182			environ = fakeenv;
183			}
184			for (i = optind; i < argc; ++i) {
185			char buf[MAX_STRING_LENGTH];
186
187			strlcpy(&fakeenv[0][3], argv[i], longest + 1);
188			if (!vflag) {
189			show(argv[i], now, FALSE);
190			continue;
191			}
192			warned = FALSE;
193			t = absolute_min_time;
194			show(argv[i], t, TRUE);
195			t += SECSPERHOUR * HOURSPERDAY;
196			show(argv[i], t, TRUE);
197			if (t < cutlotime)
198			t = cutlotime;
199			tmp = localtime(&t);
200			if (tmp != NULL) {
201			tm = *tmp;
202			strlcpy(buf, abbr(&tm), sizeof buf);
203			}
204			for ( ; ; ) {
205			if (t >= cuthitime \|\| t >= cuthitime - SECSPERHOUR * 12)
206			break;
207			newt = t + SECSPERHOUR * 12;
208			newtmp = localtime(&newt);
209			if (newtmp != NULL)
210			newtm = *newtmp;
211			if ((tmp == NULL \|\| newtmp == NULL) ? (tmp != newtmp) :
212			(delta(&newtm, &tm) != (newt - t) \|\|
213			newtm.tm_isdst != tm.tm_isdst \|\|
214			strcmp(abbr(&newtm), buf) != 0)) {
215			newt = hunt(argv[i], t, newt);
216			newtmp = localtime(&newt);
217			if (newtmp != NULL) {
218			newtm = *newtmp;
219			strlcpy(buf, abbr(&newtm), sizeof buf);
220			}
221			}
222			t = newt;
223			tm = newtm;
224			tmp = newtmp;
225			}
226			t = absolute_max_time;
227			t -= SECSPERHOUR * HOURSPERDAY;
228			show(argv[i], t, TRUE);
229			t += SECSPERHOUR * HOURSPERDAY;
230			show(argv[i], t, TRUE);
231			}
232			if (fflush(stdout) \|\| ferror(stdout)) {
233			fprintf(stderr, "%s: ", __progname);
234			perror("Error writing to standard output");
235			exit(EXIT_FAILURE);
236			}
237			return 0;
238			}
239
240			static void
241			setabsolutes(void)
242			{
243			time_t t = 0, t1 = 1;
244
245			while (t < t1) {
246			t = t1;
247			t1 = 2 * t1 + 1;
248			}
249
250			absolute_max_time = t;
251			t = -t;
252			absolute_min_time = t - 1;
253			if (t < absolute_min_time)
254			absolute_min_time = t;
255			}
256
257			static time_t
258			yeartot(const long y)
259			{
260			long myy = EPOCH_YEAR, seconds;
261			time_t t = 0;
262
263			while (myy != y) {
264			if (myy < y) {
265			seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
266			++myy;
267			if (t > absolute_max_time - seconds) {
268			t = absolute_max_time;
269			break;
270			}
271			t += seconds;
272			} else {
273			--myy;
274			seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
275			if (t < absolute_min_time + seconds) {
276			t = absolute_min_time;
277			break;
278			}
279			t -= seconds;
280			}
281			}
282			return t;
283			}
284
285			static time_t
286			hunt(char *name, time_t lot, time_t hit)
287			{
288			time_t t;
289			long diff;
290			struct tm lotm, *lotmp;
291			struct tm tm, *tmp;
292			char loab[MAX_STRING_LENGTH];
293
294			lotmp = localtime(&lot);
295			if (lotmp != NULL) {
296			lotm = *lotmp;
297			strlcpy(loab, abbr(&lotm), sizeof loab);
298			}
299			for ( ; ; ) {
300			diff = (long) (hit - lot);
301			if (diff < 2)
302			break;
303			t = lot;
304			t += diff / 2;
305			if (t <= lot)
306			++t;
307			else if (t >= hit)
308			--t;
309			tmp = localtime(&t);
310			if (tmp != NULL)
311			tm = *tmp;
312			if ((lotmp == NULL \|\| tmp == NULL) ? (lotmp == tmp) :
313			(delta(&tm, &lotm) == (t - lot) &&
314			tm.tm_isdst == lotm.tm_isdst &&
315			strcmp(abbr(&tm), loab) == 0)) {
316			lot = t;
317			lotm = tm;
318			lotmp = tmp;
319			} else
320			hit = t;
321			}
322			show(name, lot, TRUE);
323			show(name, hit, TRUE);
324			return hit;
325			}
326
327			/*
328			** Thanks to Paul Eggert for logic used in delta.
329			*/
330
331			static long
332			delta(struct tm newp, struct tm oldp)
333			{
334			long result;
335			int tmy;
336
337			if (newp->tm_year < oldp->tm_year)
338			return -delta(oldp, newp);
339			result = 0;
340			for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy)
341			result += DAYSPERNYEAR + isleap_sum(tmy, TM_YEAR_BASE);
342			result += newp->tm_yday - oldp->tm_yday;
343			result *= HOURSPERDAY;
344			result += newp->tm_hour - oldp->tm_hour;
345			result *= MINSPERHOUR;
346			result += newp->tm_min - oldp->tm_min;
347			result *= SECSPERMIN;
348			result += newp->tm_sec - oldp->tm_sec;
349			return result;
350			}
351
352			static void
353			show(char *zone, time_t t, int v)
354			{
355			struct tm *tmp;
356
357			printf("%-*s ", (int) longest, zone);
358			if (v) {
359			tmp = gmtime(&t);
360			if (tmp == NULL) {
361			printf(tformat(), t);
362			} else {
363			dumptime(tmp);
364			printf(" UTC");
365			}
366			printf(" = ");
367			}
368			tmp = localtime(&t);
369			dumptime(tmp);
370			if (tmp != NULL) {
371			if (*abbr(tmp) != '\0')
372			printf(" %s", abbr(tmp));
373			if (v) {
374			printf(" isdst=%d", tmp->tm_isdst);
375			#ifdef TM_GMTOFF
376			printf(" gmtoff=%ld", tmp->TM_GMTOFF);
377			#endif /* defined TM_GMTOFF */
378			}
379			}
380			printf("\n");
381			if (tmp != NULL && *abbr(tmp) != '\0')
382			abbrok(abbr(tmp), zone);
383			}
384
385			static char *
386			abbr(struct tm *tmp)
387			{
388			char *result;
389			static char nada;
390
391			if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1)
392			return &nada;
393			result = tzname[tmp->tm_isdst];
394			return (result == NULL) ? &nada : result;
395			}
396
397			/*
398			** The code below can fail on certain theoretical systems;
399			** it works on all known real-world systems as of 2004-12-30.
400			*/
401
402			static const char *
403			tformat(void)
404			{
405			return "%lld";
406			}
407
408			static void
409			dumptime(const struct tm *timeptr)
410			{
411			static const char wday_name[][3] = {
412			"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
413			};
414			static const char mon_name[][3] = {
415			"Jan", "Feb", "Mar", "Apr", "May", "Jun",
416			"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
417			};
418			const char wn, mn;
419			int lead, trail;
420
421			if (timeptr == NULL) {
422			printf("NULL");
423			return;
424			}
425			/*
426			** The packaged versions of localtime and gmtime never put out-of-range
427			** values in tm_wday or tm_mon, but since this code might be compiled
428			** with other (perhaps experimental) versions, paranoia is in order.
429			*/
430			if (timeptr->tm_wday < 0 \|\| timeptr->tm_wday >=
431			(int) (sizeof wday_name / sizeof wday_name[0]))
432			wn = "???";
433			else
434			wn = wday_name[timeptr->tm_wday];
435			if (timeptr->tm_mon < 0 \|\| timeptr->tm_mon >=
436			(int) (sizeof mon_name / sizeof mon_name[0]))
437			mn = "???";
438			else
439			mn = mon_name[timeptr->tm_mon];
440			printf("%.3s %.3s%3d %.2d:%.2d:%.2d ",
441			wn, mn,
442			timeptr->tm_mday, timeptr->tm_hour,
443			timeptr->tm_min, timeptr->tm_sec);
444			#define DIVISOR 10
445			trail = timeptr->tm_year % DIVISOR + TM_YEAR_BASE % DIVISOR;
446			lead = timeptr->tm_year / DIVISOR + TM_YEAR_BASE / DIVISOR +
447			trail / DIVISOR;
448			trail %= DIVISOR;
449			if (trail < 0 && lead > 0) {
450			trail += DIVISOR;
451			--lead;
452			} else if (lead < 0 && trail > 0) {
453			trail -= DIVISOR;
454			++lead;
455			}
456			if (lead == 0)
457			printf("%d", trail);
458			else
459			printf("%d%d", lead, ((trail < 0) ? -trail : trail));
460			}