xref: /trueos/contrib/tzcode/stdtime/localtime.c (revision dabf8815649df5fc5fcaf297a41e30a7fd316d56)
1 /*
2 ** This file is in the public domain, so clarified as of
3 ** 1996-06-05 by Arthur David Olson.
4 */
5 
6 #include <sys/cdefs.h>
7 #ifndef lint
8 #ifndef NOID
9 static char	elsieid[] __unused = "@(#)localtime.c	8.14";
10 #endif /* !defined NOID */
11 #endif /* !defined lint */
12 __FBSDID("$FreeBSD$");
13 
14 /*
15 ** Leap second handling from Bradley White.
16 ** POSIX-style TZ environment variable handling from Guy Harris.
17 */
18 
19 /*LINTLIBRARY*/
20 
21 #include "namespace.h"
22 #include <sys/types.h>
23 #include <sys/stat.h>
24 #include <errno.h>
25 #include <fcntl.h>
26 #include <pthread.h>
27 #include "private.h"
28 #include "un-namespace.h"
29 
30 #include "tzfile.h"
31 #include "float.h"	/* for FLT_MAX and DBL_MAX */
32 
33 #ifndef TZ_ABBR_MAX_LEN
34 #define TZ_ABBR_MAX_LEN	16
35 #endif /* !defined TZ_ABBR_MAX_LEN */
36 
37 #ifndef TZ_ABBR_CHAR_SET
38 #define TZ_ABBR_CHAR_SET \
39 	"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 :+-._"
40 #endif /* !defined TZ_ABBR_CHAR_SET */
41 
42 #ifndef TZ_ABBR_ERR_CHAR
43 #define TZ_ABBR_ERR_CHAR	'_'
44 #endif /* !defined TZ_ABBR_ERR_CHAR */
45 
46 #include "libc_private.h"
47 
48 #define	_MUTEX_LOCK(x)		if (__isthreaded) _pthread_mutex_lock(x)
49 #define	_MUTEX_UNLOCK(x)	if (__isthreaded) _pthread_mutex_unlock(x)
50 
51 #define _RWLOCK_RDLOCK(x)						\
52 		do {							\
53 			if (__isthreaded) _pthread_rwlock_rdlock(x);	\
54 		} while (0)
55 
56 #define _RWLOCK_WRLOCK(x)						\
57 		do {							\
58 			if (__isthreaded) _pthread_rwlock_wrlock(x);	\
59 		} while (0)
60 
61 #define _RWLOCK_UNLOCK(x)						\
62 		do {							\
63 			if (__isthreaded) _pthread_rwlock_unlock(x);	\
64 		} while (0)
65 
66 /*
67 ** SunOS 4.1.1 headers lack O_BINARY.
68 */
69 
70 #ifdef O_BINARY
71 #define OPEN_MODE	(O_RDONLY | O_BINARY)
72 #endif /* defined O_BINARY */
73 #ifndef O_BINARY
74 #define OPEN_MODE	O_RDONLY
75 #endif /* !defined O_BINARY */
76 
77 #ifndef WILDABBR
78 /*
79 ** Someone might make incorrect use of a time zone abbreviation:
80 **	1.	They might reference tzname[0] before calling tzset (explicitly
81 **		or implicitly).
82 **	2.	They might reference tzname[1] before calling tzset (explicitly
83 **		or implicitly).
84 **	3.	They might reference tzname[1] after setting to a time zone
85 **		in which Daylight Saving Time is never observed.
86 **	4.	They might reference tzname[0] after setting to a time zone
87 **		in which Standard Time is never observed.
88 **	5.	They might reference tm.TM_ZONE after calling offtime.
89 ** What's best to do in the above cases is open to debate;
90 ** for now, we just set things up so that in any of the five cases
91 ** WILDABBR is used. Another possibility: initialize tzname[0] to the
92 ** string "tzname[0] used before set", and similarly for the other cases.
93 ** And another: initialize tzname[0] to "ERA", with an explanation in the
94 ** manual page of what this "time zone abbreviation" means (doing this so
95 ** that tzname[0] has the "normal" length of three characters).
96 */
97 #define WILDABBR	"   "
98 #endif /* !defined WILDABBR */
99 
100 static char		wildabbr[] = WILDABBR;
101 
102 /*
103  * In June 2004 it was decided UTC was a more appropriate default time
104  * zone than GMT.
105  */
106 
107 static const char	gmt[] = "UTC";
108 
109 /*
110 ** The DST rules to use if TZ has no rules and we can't load TZDEFRULES.
111 ** We default to US rules as of 1999-08-17.
112 ** POSIX 1003.1 section 8.1.1 says that the default DST rules are
113 ** implementation dependent; for historical reasons, US rules are a
114 ** common default.
115 */
116 #ifndef TZDEFRULESTRING
117 #define TZDEFRULESTRING ",M4.1.0,M10.5.0"
118 #endif /* !defined TZDEFDST */
119 
120 struct ttinfo {				/* time type information */
121 	long		tt_gmtoff;	/* UTC offset in seconds */
122 	int		tt_isdst;	/* used to set tm_isdst */
123 	int		tt_abbrind;	/* abbreviation list index */
124 	int		tt_ttisstd;	/* TRUE if transition is std time */
125 	int		tt_ttisgmt;	/* TRUE if transition is UTC */
126 };
127 
128 struct lsinfo {				/* leap second information */
129 	time_t		ls_trans;	/* transition time */
130 	long		ls_corr;	/* correction to apply */
131 };
132 
133 #define BIGGEST(a, b)	(((a) > (b)) ? (a) : (b))
134 
135 #ifdef TZNAME_MAX
136 #define MY_TZNAME_MAX	TZNAME_MAX
137 #endif /* defined TZNAME_MAX */
138 #ifndef TZNAME_MAX
139 #define MY_TZNAME_MAX	255
140 #endif /* !defined TZNAME_MAX */
141 
142 struct state {
143 	int		leapcnt;
144 	int		timecnt;
145 	int		typecnt;
146 	int		charcnt;
147 	int		goback;
148 	int		goahead;
149 	time_t		ats[TZ_MAX_TIMES];
150 	unsigned char	types[TZ_MAX_TIMES];
151 	struct ttinfo	ttis[TZ_MAX_TYPES];
152 	char		chars[BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt),
153 				(2 * (MY_TZNAME_MAX + 1)))];
154 	struct lsinfo	lsis[TZ_MAX_LEAPS];
155 };
156 
157 struct rule {
158 	int		r_type;		/* type of rule--see below */
159 	int		r_day;		/* day number of rule */
160 	int		r_week;		/* week number of rule */
161 	int		r_mon;		/* month number of rule */
162 	long		r_time;		/* transition time of rule */
163 };
164 
165 #define JULIAN_DAY		0	/* Jn - Julian day */
166 #define DAY_OF_YEAR		1	/* n - day of year */
167 #define MONTH_NTH_DAY_OF_WEEK	2	/* Mm.n.d - month, week, day of week */
168 
169 /*
170 ** Prototypes for static functions.
171 */
172 
173 static long		detzcode(const char * codep);
174 static time_t		detzcode64(const char * codep);
175 static int		differ_by_repeat(time_t t1, time_t t0);
176 static const char *	getzname(const char * strp);
177 static const char *	getqzname(const char * strp, const int delim);
178 static const char *	getnum(const char * strp, int * nump, int min,
179 				int max);
180 static const char *	getsecs(const char * strp, long * secsp);
181 static const char *	getoffset(const char * strp, long * offsetp);
182 static const char *	getrule(const char * strp, struct rule * rulep);
183 static void		gmtload(struct state * sp);
184 static struct tm *	gmtsub(const time_t * timep, long offset,
185 				struct tm * tmp);
186 static struct tm *	localsub(const time_t * timep, long offset,
187 				struct tm * tmp);
188 static int		increment_overflow(int * number, int delta);
189 static int		leaps_thru_end_of(int y);
190 static int		long_increment_overflow(long * number, int delta);
191 static int		long_normalize_overflow(long * tensptr,
192 				int * unitsptr, int base);
193 static int		normalize_overflow(int * tensptr, int * unitsptr,
194 				int base);
195 static void		settzname(void);
196 static time_t		time1(struct tm * tmp,
197 				struct tm * (*funcp)(const time_t *,
198 				long, struct tm *),
199 				long offset);
200 static time_t		time2(struct tm *tmp,
201 				struct tm * (*funcp)(const time_t *,
202 				long, struct tm*),
203 				long offset, int * okayp);
204 static time_t		time2sub(struct tm *tmp,
205 				struct tm * (*funcp)(const time_t *,
206 				long, struct tm*),
207 				long offset, int * okayp, int do_norm_secs);
208 static struct tm *	timesub(const time_t * timep, long offset,
209 				const struct state * sp, struct tm * tmp);
210 static int		tmcomp(const struct tm * atmp,
211 				const struct tm * btmp);
212 static time_t		transtime(time_t janfirst, int year,
213 				const struct rule * rulep, long offset);
214 static int		typesequiv(const struct state * sp, int a, int b);
215 static int		tzload(const char * name, struct state * sp,
216 				int doextend);
217 static int		tzparse(const char * name, struct state * sp,
218 				int lastditch);
219 
220 #ifdef ALL_STATE
221 static struct state *	lclptr;
222 static struct state *	gmtptr;
223 #endif /* defined ALL_STATE */
224 
225 #ifndef ALL_STATE
226 static struct state	lclmem;
227 static struct state	gmtmem;
228 #define lclptr		(&lclmem)
229 #define gmtptr		(&gmtmem)
230 #endif /* State Farm */
231 
232 #ifndef TZ_STRLEN_MAX
233 #define TZ_STRLEN_MAX 255
234 #endif /* !defined TZ_STRLEN_MAX */
235 
236 static char		lcl_TZname[TZ_STRLEN_MAX + 1];
237 static int		lcl_is_set;
238 static pthread_once_t	gmt_once = PTHREAD_ONCE_INIT;
239 static pthread_rwlock_t	lcl_rwlock = PTHREAD_RWLOCK_INITIALIZER;
240 static pthread_once_t	gmtime_once = PTHREAD_ONCE_INIT;
241 static pthread_key_t	gmtime_key;
242 static int		gmtime_key_error;
243 static pthread_once_t	localtime_once = PTHREAD_ONCE_INIT;
244 static pthread_key_t	localtime_key;
245 static int		localtime_key_error;
246 
247 char *			tzname[2] = {
248 	wildabbr,
249 	wildabbr
250 };
251 
252 /*
253 ** Section 4.12.3 of X3.159-1989 requires that
254 **	Except for the strftime function, these functions [asctime,
255 **	ctime, gmtime, localtime] return values in one of two static
256 **	objects: a broken-down time structure and an array of char.
257 ** Thanks to Paul Eggert for noting this.
258 */
259 
260 static struct tm	tm;
261 
262 #ifdef USG_COMPAT
263 time_t			timezone = 0;
264 int			daylight = 0;
265 #endif /* defined USG_COMPAT */
266 
267 #ifdef ALTZONE
268 time_t			altzone = 0;
269 #endif /* defined ALTZONE */
270 
271 static long
detzcode(codep)272 detzcode(codep)
273 const char * const	codep;
274 {
275 	long	result;
276 	int	i;
277 
278 	result = (codep[0] & 0x80) ? ~0L : 0;
279 	for (i = 0; i < 4; ++i)
280 		result = (result << 8) | (codep[i] & 0xff);
281 	return result;
282 }
283 
284 static time_t
detzcode64(codep)285 detzcode64(codep)
286 const char * const	codep;
287 {
288 	register time_t	result;
289 	register int	i;
290 
291 	result = (codep[0] & 0x80) ?  (~(int_fast64_t) 0) : 0;
292 	for (i = 0; i < 8; ++i)
293 		result = result * 256 + (codep[i] & 0xff);
294 	return result;
295 }
296 
297 static void
settzname(void)298 settzname(void)
299 {
300 	struct state * 	sp = lclptr;
301 	int			i;
302 
303 	tzname[0] = wildabbr;
304 	tzname[1] = wildabbr;
305 #ifdef USG_COMPAT
306 	daylight = 0;
307 	timezone = 0;
308 #endif /* defined USG_COMPAT */
309 #ifdef ALTZONE
310 	altzone = 0;
311 #endif /* defined ALTZONE */
312 #ifdef ALL_STATE
313 	if (sp == NULL) {
314 		tzname[0] = tzname[1] = gmt;
315 		return;
316 	}
317 #endif /* defined ALL_STATE */
318 	/*
319 	** And to get the latest zone names into tzname. . .
320 	*/
321 	for (i = 0; i < sp->typecnt; ++i) {
322 		const struct ttinfo * const ttisp = &sp->ttis[sp->types[i]];
323 
324 		tzname[ttisp->tt_isdst] =
325 			&sp->chars[ttisp->tt_abbrind];
326 #ifdef USG_COMPAT
327 		if (ttisp->tt_isdst)
328 			daylight = 1;
329 		if (!ttisp->tt_isdst)
330 			timezone = -(ttisp->tt_gmtoff);
331 #endif /* defined USG_COMPAT */
332 #ifdef ALTZONE
333 		if (ttisp->tt_isdst)
334 			altzone = -(ttisp->tt_gmtoff);
335 #endif /* defined ALTZONE */
336 	}
337 	/*
338 	** Finally, scrub the abbreviations.
339 	** First, replace bogus characters.
340 	*/
341 	for (i = 0; i < sp->charcnt; ++i)
342 		if (strchr(TZ_ABBR_CHAR_SET, sp->chars[i]) == NULL)
343 			sp->chars[i] = TZ_ABBR_ERR_CHAR;
344 	/*
345 	** Second, truncate long abbreviations.
346 	*/
347 	for (i = 0; i < sp->typecnt; ++i) {
348 		register const struct ttinfo * const	ttisp = &sp->ttis[i];
349 		register char *				cp = &sp->chars[ttisp->tt_abbrind];
350 
351 		if (strlen(cp) > TZ_ABBR_MAX_LEN &&
352 			strcmp(cp, GRANDPARENTED) != 0)
353 				*(cp + TZ_ABBR_MAX_LEN) = '\0';
354 	}
355 }
356 
357 static int
differ_by_repeat(t1,t0)358 differ_by_repeat(t1, t0)
359 const time_t	t1;
360 const time_t	t0;
361 {
362 	int_fast64_t _t0 = t0;
363 	int_fast64_t _t1 = t1;
364 
365 	if (TYPE_INTEGRAL(time_t) &&
366 		TYPE_BIT(time_t) - TYPE_SIGNED(time_t) < SECSPERREPEAT_BITS)
367 			return 0;
368 	//turn ((int_fast64_t)(t1 - t0) == SECSPERREPEAT);
369 	return _t1 - _t0 == SECSPERREPEAT;
370 }
371 
372 static int
tzload(name,sp,doextend)373 tzload(name, sp, doextend)
374 const char *		name;
375 struct state * const	sp;
376 register const int	doextend;
377 {
378 	const char *	p;
379 	int		i;
380 	int		fid;
381 	int		stored;
382 	int		nread;
383 	int		res;
384 	union {
385 		struct tzhead	tzhead;
386 		char		buf[2 * sizeof(struct tzhead) +
387 					2 * sizeof *sp +
388 					4 * TZ_MAX_TIMES];
389 	} *u;
390 
391 	u = NULL;
392 	res = -1;
393 	sp->goback = sp->goahead = FALSE;
394 
395 	/* XXX The following is from OpenBSD, and I'm not sure it is correct */
396 	if (name != NULL && issetugid() != 0)
397 		if ((name[0] == ':' && name[1] == '/') ||
398 		    name[0] == '/' || strchr(name, '.'))
399 			name = NULL;
400 	if (name == NULL && (name = TZDEFAULT) == NULL)
401 		return -1;
402 	{
403 		int	doaccess;
404 		struct stat	stab;
405 		/*
406 		** Section 4.9.1 of the C standard says that
407 		** "FILENAME_MAX expands to an integral constant expression
408 		** that is the size needed for an array of char large enough
409 		** to hold the longest file name string that the implementation
410 		** guarantees can be opened."
411 		*/
412 		char		*fullname;
413 
414 		fullname = malloc(FILENAME_MAX + 1);
415 		if (fullname == NULL)
416 			goto out;
417 
418 		if (name[0] == ':')
419 			++name;
420 		doaccess = name[0] == '/';
421 		if (!doaccess) {
422 			if ((p = TZDIR) == NULL) {
423 				free(fullname);
424 				return -1;
425 			}
426 			if (strlen(p) + 1 + strlen(name) >= FILENAME_MAX) {
427 				free(fullname);
428 				return -1;
429 			}
430 			(void) strcpy(fullname, p);
431 			(void) strcat(fullname, "/");
432 			(void) strcat(fullname, name);
433 			/*
434 			** Set doaccess if '.' (as in "../") shows up in name.
435 			*/
436 			if (strchr(name, '.') != NULL)
437 				doaccess = TRUE;
438 			name = fullname;
439 		}
440 		if (doaccess && access(name, R_OK) != 0) {
441 			free(fullname);
442 		     	return -1;
443 		}
444 		if ((fid = _open(name, OPEN_MODE)) == -1) {
445 			free(fullname);
446 			return -1;
447 		}
448 		if ((_fstat(fid, &stab) < 0) || !S_ISREG(stab.st_mode)) {
449 			free(fullname);
450 			_close(fid);
451 			return -1;
452 		}
453 		free(fullname);
454 	}
455 	u = malloc(sizeof(*u));
456 	if (u == NULL)
457 		goto out;
458 	nread = _read(fid, u->buf, sizeof u->buf);
459 	if (_close(fid) < 0 || nread <= 0)
460 		goto out;
461 	for (stored = 4; stored <= 8; stored *= 2) {
462 		int		ttisstdcnt;
463 		int		ttisgmtcnt;
464 
465 		ttisstdcnt = (int) detzcode(u->tzhead.tzh_ttisstdcnt);
466 		ttisgmtcnt = (int) detzcode(u->tzhead.tzh_ttisgmtcnt);
467 		sp->leapcnt = (int) detzcode(u->tzhead.tzh_leapcnt);
468 		sp->timecnt = (int) detzcode(u->tzhead.tzh_timecnt);
469 		sp->typecnt = (int) detzcode(u->tzhead.tzh_typecnt);
470 		sp->charcnt = (int) detzcode(u->tzhead.tzh_charcnt);
471 		p = u->tzhead.tzh_charcnt + sizeof u->tzhead.tzh_charcnt;
472 		if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS ||
473 			sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES ||
474 			sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES ||
475 			sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS ||
476 			(ttisstdcnt != sp->typecnt && ttisstdcnt != 0) ||
477 			(ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0))
478 				goto out;
479 		if (nread - (p - u->buf) <
480 			sp->timecnt * stored +		/* ats */
481 			sp->timecnt +			/* types */
482 			sp->typecnt * 6 +		/* ttinfos */
483 			sp->charcnt +			/* chars */
484 			sp->leapcnt * (stored + 4) +	/* lsinfos */
485 			ttisstdcnt +			/* ttisstds */
486 			ttisgmtcnt)			/* ttisgmts */
487 				goto out;
488 		for (i = 0; i < sp->timecnt; ++i) {
489 			sp->ats[i] = (stored == 4) ?
490 				detzcode(p) : detzcode64(p);
491 			p += stored;
492 		}
493 		for (i = 0; i < sp->timecnt; ++i) {
494 			sp->types[i] = (unsigned char) *p++;
495 			if (sp->types[i] >= sp->typecnt)
496 				goto out;
497 		}
498 		for (i = 0; i < sp->typecnt; ++i) {
499 			struct ttinfo *	ttisp;
500 
501 			ttisp = &sp->ttis[i];
502 			ttisp->tt_gmtoff = detzcode(p);
503 			p += 4;
504 			ttisp->tt_isdst = (unsigned char) *p++;
505 			if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1)
506 				goto out;
507 			ttisp->tt_abbrind = (unsigned char) *p++;
508 			if (ttisp->tt_abbrind < 0 ||
509 				ttisp->tt_abbrind > sp->charcnt)
510 					goto out;
511 		}
512 		for (i = 0; i < sp->charcnt; ++i)
513 			sp->chars[i] = *p++;
514 		sp->chars[i] = '\0';	/* ensure '\0' at end */
515 		for (i = 0; i < sp->leapcnt; ++i) {
516 			struct lsinfo *	lsisp;
517 
518 			lsisp = &sp->lsis[i];
519 			lsisp->ls_trans = (stored == 4) ?
520 				detzcode(p) : detzcode64(p);
521 			p += stored;
522 			lsisp->ls_corr = detzcode(p);
523 			p += 4;
524 		}
525 		for (i = 0; i < sp->typecnt; ++i) {
526 			struct ttinfo *	ttisp;
527 
528 			ttisp = &sp->ttis[i];
529 			if (ttisstdcnt == 0)
530 				ttisp->tt_ttisstd = FALSE;
531 			else {
532 				ttisp->tt_ttisstd = *p++;
533 				if (ttisp->tt_ttisstd != TRUE &&
534 					ttisp->tt_ttisstd != FALSE)
535 						goto out;
536 			}
537 		}
538 		for (i = 0; i < sp->typecnt; ++i) {
539 			struct ttinfo *	ttisp;
540 
541 			ttisp = &sp->ttis[i];
542 			if (ttisgmtcnt == 0)
543 				ttisp->tt_ttisgmt = FALSE;
544 			else {
545 				ttisp->tt_ttisgmt = *p++;
546 				if (ttisp->tt_ttisgmt != TRUE &&
547 					ttisp->tt_ttisgmt != FALSE)
548 						goto out;
549 			}
550 		}
551 		/*
552 		** Out-of-sort ats should mean we're running on a
553 		** signed time_t system but using a data file with
554 		** unsigned values (or vice versa).
555 		*/
556 		for (i = 0; i < sp->timecnt - 2; ++i)
557 			if (sp->ats[i] > sp->ats[i + 1]) {
558 				++i;
559 				if (TYPE_SIGNED(time_t)) {
560 					/*
561 					** Ignore the end (easy).
562 					*/
563 					sp->timecnt = i;
564 				} else {
565 					/*
566 					** Ignore the beginning (harder).
567 					*/
568 					register int	j;
569 
570 					for (j = 0; j + i < sp->timecnt; ++j) {
571 						sp->ats[j] = sp->ats[j + i];
572 						sp->types[j] = sp->types[j + i];
573 					}
574 					sp->timecnt = j;
575 				}
576 				break;
577 			}
578 		/*
579 		** If this is an old file, we're done.
580 		*/
581 		if (u->tzhead.tzh_version[0] == '\0')
582 			break;
583 		nread -= p - u->buf;
584 		for (i = 0; i < nread; ++i)
585 			u->buf[i] = p[i];
586 		/*
587 		** If this is a narrow integer time_t system, we're done.
588 		*/
589 		if (stored >= (int) sizeof(time_t) && TYPE_INTEGRAL(time_t))
590 			break;
591 	}
592 	if (doextend && nread > 2 &&
593 		u->buf[0] == '\n' && u->buf[nread - 1] == '\n' &&
594 		sp->typecnt + 2 <= TZ_MAX_TYPES) {
595 			struct state	*ts;
596 			register int	result;
597 
598 			ts = malloc(sizeof(*ts));
599 			if (ts == NULL)
600 				goto out;
601 			u->buf[nread - 1] = '\0';
602 			result = tzparse(&u->buf[1], ts, FALSE);
603 			if (result == 0 && ts->typecnt == 2 &&
604 				sp->charcnt + ts->charcnt <= TZ_MAX_CHARS) {
605 					for (i = 0; i < 2; ++i)
606 						ts->ttis[i].tt_abbrind +=
607 							sp->charcnt;
608 					for (i = 0; i < ts->charcnt; ++i)
609 						sp->chars[sp->charcnt++] =
610 							ts->chars[i];
611 					i = 0;
612 					while (i < ts->timecnt &&
613 						ts->ats[i] <=
614 						sp->ats[sp->timecnt - 1])
615 							++i;
616 					while (i < ts->timecnt &&
617 					    sp->timecnt < TZ_MAX_TIMES) {
618 						sp->ats[sp->timecnt] =
619 							ts->ats[i];
620 						sp->types[sp->timecnt] =
621 							sp->typecnt +
622 							ts->types[i];
623 						++sp->timecnt;
624 						++i;
625 					}
626 					sp->ttis[sp->typecnt++] = ts->ttis[0];
627 					sp->ttis[sp->typecnt++] = ts->ttis[1];
628 			}
629 			free(ts);
630 	}
631 	if (sp->timecnt > 1) {
632 		for (i = 1; i < sp->timecnt; ++i)
633 			if (typesequiv(sp, sp->types[i], sp->types[0]) &&
634 				differ_by_repeat(sp->ats[i], sp->ats[0])) {
635 					sp->goback = TRUE;
636 					break;
637 				}
638 		for (i = sp->timecnt - 2; i >= 0; --i)
639 			if (typesequiv(sp, sp->types[sp->timecnt - 1],
640 				sp->types[i]) &&
641 				differ_by_repeat(sp->ats[sp->timecnt - 1],
642 				sp->ats[i])) {
643 					sp->goahead = TRUE;
644 					break;
645 		}
646 	}
647 	res = 0;
648 out:
649 	free(u);
650 	return (res);
651 }
652 
653 static int
typesequiv(sp,a,b)654 typesequiv(sp, a, b)
655 const struct state * const	sp;
656 const int			a;
657 const int			b;
658 {
659 	register int	result;
660 
661 	if (sp == NULL ||
662 		a < 0 || a >= sp->typecnt ||
663 		b < 0 || b >= sp->typecnt)
664 			result = FALSE;
665 	else {
666 		register const struct ttinfo *	ap = &sp->ttis[a];
667 		register const struct ttinfo *	bp = &sp->ttis[b];
668 		result = ap->tt_gmtoff == bp->tt_gmtoff &&
669 			ap->tt_isdst == bp->tt_isdst &&
670 			ap->tt_ttisstd == bp->tt_ttisstd &&
671 			ap->tt_ttisgmt == bp->tt_ttisgmt &&
672 			strcmp(&sp->chars[ap->tt_abbrind],
673 			&sp->chars[bp->tt_abbrind]) == 0;
674 	}
675 	return result;
676 }
677 
678 static const int	mon_lengths[2][MONSPERYEAR] = {
679 	{ 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
680 	{ 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }
681 };
682 
683 static const int	year_lengths[2] = {
684 	DAYSPERNYEAR, DAYSPERLYEAR
685 };
686 
687 /*
688 ** Given a pointer into a time zone string, scan until a character that is not
689 ** a valid character in a zone name is found. Return a pointer to that
690 ** character.
691 */
692 
693 static const char *
getzname(strp)694 getzname(strp)
695 const char *	strp;
696 {
697 	char	c;
698 
699 	while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' &&
700 		c != '+')
701 			++strp;
702 	return strp;
703 }
704 
705 /*
706 ** Given a pointer into an extended time zone string, scan until the ending
707 ** delimiter of the zone name is located. Return a pointer to the delimiter.
708 **
709 ** As with getzname above, the legal character set is actually quite
710 ** restricted, with other characters producing undefined results.
711 ** We don't do any checking here; checking is done later in common-case code.
712 */
713 
714 static const char *
getqzname(register const char * strp,const int delim)715 getqzname(register const char *strp, const int delim)
716 {
717 	register int	c;
718 
719 	while ((c = *strp) != '\0' && c != delim)
720 		++strp;
721 	return strp;
722 }
723 
724 /*
725 ** Given a pointer into a time zone string, extract a number from that string.
726 ** Check that the number is within a specified range; if it is not, return
727 ** NULL.
728 ** Otherwise, return a pointer to the first character not part of the number.
729 */
730 
731 static const char *
getnum(strp,nump,min,max)732 getnum(strp, nump, min, max)
733 const char *	strp;
734 int * const		nump;
735 const int		min;
736 const int		max;
737 {
738 	char	c;
739 	int	num;
740 
741 	if (strp == NULL || !is_digit(c = *strp))
742 		return NULL;
743 	num = 0;
744 	do {
745 		num = num * 10 + (c - '0');
746 		if (num > max)
747 			return NULL;	/* illegal value */
748 		c = *++strp;
749 	} while (is_digit(c));
750 	if (num < min)
751 		return NULL;		/* illegal value */
752 	*nump = num;
753 	return strp;
754 }
755 
756 /*
757 ** Given a pointer into a time zone string, extract a number of seconds,
758 ** in hh[:mm[:ss]] form, from the string.
759 ** If any error occurs, return NULL.
760 ** Otherwise, return a pointer to the first character not part of the number
761 ** of seconds.
762 */
763 
764 static const char *
getsecs(strp,secsp)765 getsecs(strp, secsp)
766 const char *	strp;
767 long * const		secsp;
768 {
769 	int	num;
770 
771 	/*
772 	** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like
773 	** "M10.4.6/26", which does not conform to Posix,
774 	** but which specifies the equivalent of
775 	** ``02:00 on the first Sunday on or after 23 Oct''.
776 	*/
777 	strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1);
778 	if (strp == NULL)
779 		return NULL;
780 	*secsp = num * (long) SECSPERHOUR;
781 	if (*strp == ':') {
782 		++strp;
783 		strp = getnum(strp, &num, 0, MINSPERHOUR - 1);
784 		if (strp == NULL)
785 			return NULL;
786 		*secsp += num * SECSPERMIN;
787 		if (*strp == ':') {
788 			++strp;
789 			/* `SECSPERMIN' allows for leap seconds. */
790 			strp = getnum(strp, &num, 0, SECSPERMIN);
791 			if (strp == NULL)
792 				return NULL;
793 			*secsp += num;
794 		}
795 	}
796 	return strp;
797 }
798 
799 /*
800 ** Given a pointer into a time zone string, extract an offset, in
801 ** [+-]hh[:mm[:ss]] form, from the string.
802 ** If any error occurs, return NULL.
803 ** Otherwise, return a pointer to the first character not part of the time.
804 */
805 
806 static const char *
getoffset(strp,offsetp)807 getoffset(strp, offsetp)
808 const char *	strp;
809 long * const		offsetp;
810 {
811 	int	neg = 0;
812 
813 	if (*strp == '-') {
814 		neg = 1;
815 		++strp;
816 	} else if (*strp == '+')
817 		++strp;
818 	strp = getsecs(strp, offsetp);
819 	if (strp == NULL)
820 		return NULL;		/* illegal time */
821 	if (neg)
822 		*offsetp = -*offsetp;
823 	return strp;
824 }
825 
826 /*
827 ** Given a pointer into a time zone string, extract a rule in the form
828 ** date[/time]. See POSIX section 8 for the format of "date" and "time".
829 ** If a valid rule is not found, return NULL.
830 ** Otherwise, return a pointer to the first character not part of the rule.
831 */
832 
833 static const char *
getrule(strp,rulep)834 getrule(strp, rulep)
835 const char *			strp;
836 struct rule * const	rulep;
837 {
838 	if (*strp == 'J') {
839 		/*
840 		** Julian day.
841 		*/
842 		rulep->r_type = JULIAN_DAY;
843 		++strp;
844 		strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR);
845 	} else if (*strp == 'M') {
846 		/*
847 		** Month, week, day.
848 		*/
849 		rulep->r_type = MONTH_NTH_DAY_OF_WEEK;
850 		++strp;
851 		strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR);
852 		if (strp == NULL)
853 			return NULL;
854 		if (*strp++ != '.')
855 			return NULL;
856 		strp = getnum(strp, &rulep->r_week, 1, 5);
857 		if (strp == NULL)
858 			return NULL;
859 		if (*strp++ != '.')
860 			return NULL;
861 		strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1);
862 	} else if (is_digit(*strp)) {
863 		/*
864 		** Day of year.
865 		*/
866 		rulep->r_type = DAY_OF_YEAR;
867 		strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1);
868 	} else	return NULL;		/* invalid format */
869 	if (strp == NULL)
870 		return NULL;
871 	if (*strp == '/') {
872 		/*
873 		** Time specified.
874 		*/
875 		++strp;
876 		strp = getsecs(strp, &rulep->r_time);
877 	} else	rulep->r_time = 2 * SECSPERHOUR;	/* default = 2:00:00 */
878 	return strp;
879 }
880 
881 /*
882 ** Given the Epoch-relative time of January 1, 00:00:00 UTC, in a year, the
883 ** year, a rule, and the offset from UTC at the time that rule takes effect,
884 ** calculate the Epoch-relative time that rule takes effect.
885 */
886 
887 static time_t
transtime(janfirst,year,rulep,offset)888 transtime(janfirst, year, rulep, offset)
889 const time_t				janfirst;
890 const int				year;
891 const struct rule * const	rulep;
892 const long				offset;
893 {
894 	int	leapyear;
895 	time_t	value;
896 	int	i;
897 	int		d, m1, yy0, yy1, yy2, dow;
898 
899 	INITIALIZE(value);
900 	leapyear = isleap(year);
901 	switch (rulep->r_type) {
902 
903 	case JULIAN_DAY:
904 		/*
905 		** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap
906 		** years.
907 		** In non-leap years, or if the day number is 59 or less, just
908 		** add SECSPERDAY times the day number-1 to the time of
909 		** January 1, midnight, to get the day.
910 		*/
911 		value = janfirst + (rulep->r_day - 1) * SECSPERDAY;
912 		if (leapyear && rulep->r_day >= 60)
913 			value += SECSPERDAY;
914 		break;
915 
916 	case DAY_OF_YEAR:
917 		/*
918 		** n - day of year.
919 		** Just add SECSPERDAY times the day number to the time of
920 		** January 1, midnight, to get the day.
921 		*/
922 		value = janfirst + rulep->r_day * SECSPERDAY;
923 		break;
924 
925 	case MONTH_NTH_DAY_OF_WEEK:
926 		/*
927 		** Mm.n.d - nth "dth day" of month m.
928 		*/
929 		value = janfirst;
930 		for (i = 0; i < rulep->r_mon - 1; ++i)
931 			value += mon_lengths[leapyear][i] * SECSPERDAY;
932 
933 		/*
934 		** Use Zeller's Congruence to get day-of-week of first day of
935 		** month.
936 		*/
937 		m1 = (rulep->r_mon + 9) % 12 + 1;
938 		yy0 = (rulep->r_mon <= 2) ? (year - 1) : year;
939 		yy1 = yy0 / 100;
940 		yy2 = yy0 % 100;
941 		dow = ((26 * m1 - 2) / 10 +
942 			1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7;
943 		if (dow < 0)
944 			dow += DAYSPERWEEK;
945 
946 		/*
947 		** "dow" is the day-of-week of the first day of the month. Get
948 		** the day-of-month (zero-origin) of the first "dow" day of the
949 		** month.
950 		*/
951 		d = rulep->r_day - dow;
952 		if (d < 0)
953 			d += DAYSPERWEEK;
954 		for (i = 1; i < rulep->r_week; ++i) {
955 			if (d + DAYSPERWEEK >=
956 				mon_lengths[leapyear][rulep->r_mon - 1])
957 					break;
958 			d += DAYSPERWEEK;
959 		}
960 
961 		/*
962 		** "d" is the day-of-month (zero-origin) of the day we want.
963 		*/
964 		value += d * SECSPERDAY;
965 		break;
966 	}
967 
968 	/*
969 	** "value" is the Epoch-relative time of 00:00:00 UTC on the day in
970 	** question. To get the Epoch-relative time of the specified local
971 	** time on that day, add the transition time and the current offset
972 	** from UTC.
973 	*/
974 	return value + rulep->r_time + offset;
975 }
976 
977 /*
978 ** Given a POSIX section 8-style TZ string, fill in the rule tables as
979 ** appropriate.
980 */
981 
982 static int
tzparse(name,sp,lastditch)983 tzparse(name, sp, lastditch)
984 const char *			name;
985 struct state * const	sp;
986 const int			lastditch;
987 {
988 	const char *			stdname;
989 	const char *			dstname;
990 	size_t				stdlen;
991 	size_t				dstlen;
992 	long				stdoffset;
993 	long				dstoffset;
994 	time_t *		atp;
995 	unsigned char *	typep;
996 	char *			cp;
997 	int			load_result;
998 
999 	INITIALIZE(dstname);
1000 	stdname = name;
1001 	if (lastditch) {
1002 		stdlen = strlen(name);	/* length of standard zone name */
1003 		name += stdlen;
1004 		if (stdlen >= sizeof sp->chars)
1005 			stdlen = (sizeof sp->chars) - 1;
1006 		stdoffset = 0;
1007 	} else {
1008 		if (*name == '<') {
1009 			name++;
1010 			stdname = name;
1011 			name = getqzname(name, '>');
1012 			if (*name != '>')
1013 				return (-1);
1014 			stdlen = name - stdname;
1015 			name++;
1016 		} else {
1017 			name = getzname(name);
1018 			stdlen = name - stdname;
1019 		}
1020 		if (*name == '\0')
1021 			return -1;	/* was "stdoffset = 0;" */
1022 		else {
1023 			name = getoffset(name, &stdoffset);
1024 			if (name == NULL)
1025 				return -1;
1026 		}
1027 	}
1028 	load_result = tzload(TZDEFRULES, sp, FALSE);
1029 	if (load_result != 0)
1030 		sp->leapcnt = 0;		/* so, we're off a little */
1031 	if (*name != '\0') {
1032 		if (*name == '<') {
1033 			dstname = ++name;
1034 			name = getqzname(name, '>');
1035 			if (*name != '>')
1036 				return -1;
1037 			dstlen = name - dstname;
1038 			name++;
1039 		} else {
1040 			dstname = name;
1041 			name = getzname(name);
1042 			dstlen = name - dstname; /* length of DST zone name */
1043 		}
1044 		if (*name != '\0' && *name != ',' && *name != ';') {
1045 			name = getoffset(name, &dstoffset);
1046 			if (name == NULL)
1047 				return -1;
1048 		} else	dstoffset = stdoffset - SECSPERHOUR;
1049 		if (*name == '\0' && load_result != 0)
1050 			name = TZDEFRULESTRING;
1051 		if (*name == ',' || *name == ';') {
1052 			struct rule	start;
1053 			struct rule	end;
1054 			int	year;
1055 			time_t	janfirst;
1056 			time_t		starttime;
1057 			time_t		endtime;
1058 
1059 			++name;
1060 			if ((name = getrule(name, &start)) == NULL)
1061 				return -1;
1062 			if (*name++ != ',')
1063 				return -1;
1064 			if ((name = getrule(name, &end)) == NULL)
1065 				return -1;
1066 			if (*name != '\0')
1067 				return -1;
1068 			sp->typecnt = 2;	/* standard time and DST */
1069 			/*
1070 			** Two transitions per year, from EPOCH_YEAR forward.
1071 			*/
1072 			sp->ttis[0].tt_gmtoff = -dstoffset;
1073 			sp->ttis[0].tt_isdst = 1;
1074 			sp->ttis[0].tt_abbrind = stdlen + 1;
1075 			sp->ttis[1].tt_gmtoff = -stdoffset;
1076 			sp->ttis[1].tt_isdst = 0;
1077 			sp->ttis[1].tt_abbrind = 0;
1078 			atp = sp->ats;
1079 			typep = sp->types;
1080 			janfirst = 0;
1081 			sp->timecnt = 0;
1082 			for (year = EPOCH_YEAR;
1083 			    sp->timecnt + 2 <= TZ_MAX_TIMES;
1084 			    ++year) {
1085 			    	time_t	newfirst;
1086 
1087 				starttime = transtime(janfirst, year, &start,
1088 					stdoffset);
1089 				endtime = transtime(janfirst, year, &end,
1090 					dstoffset);
1091 				if (starttime > endtime) {
1092 					*atp++ = endtime;
1093 					*typep++ = 1;	/* DST ends */
1094 					*atp++ = starttime;
1095 					*typep++ = 0;	/* DST begins */
1096 				} else {
1097 					*atp++ = starttime;
1098 					*typep++ = 0;	/* DST begins */
1099 					*atp++ = endtime;
1100 					*typep++ = 1;	/* DST ends */
1101 				}
1102 				sp->timecnt += 2;
1103 				newfirst = janfirst;
1104 				newfirst += year_lengths[isleap(year)] *
1105 					SECSPERDAY;
1106 				if (newfirst <= janfirst)
1107 					break;
1108 				janfirst = newfirst;
1109 			}
1110 		} else {
1111 			long	theirstdoffset;
1112 			long	theirdstoffset;
1113 			long	theiroffset;
1114 			int	isdst;
1115 			int	i;
1116 			int	j;
1117 
1118 			if (*name != '\0')
1119 				return -1;
1120 			/*
1121 			** Initial values of theirstdoffset and theirdstoffset.
1122 			*/
1123 			theirstdoffset = 0;
1124 			for (i = 0; i < sp->timecnt; ++i) {
1125 				j = sp->types[i];
1126 				if (!sp->ttis[j].tt_isdst) {
1127 					theirstdoffset =
1128 						-sp->ttis[j].tt_gmtoff;
1129 					break;
1130 				}
1131 			}
1132 			theirdstoffset = 0;
1133 			for (i = 0; i < sp->timecnt; ++i) {
1134 				j = sp->types[i];
1135 				if (sp->ttis[j].tt_isdst) {
1136 					theirdstoffset =
1137 						-sp->ttis[j].tt_gmtoff;
1138 					break;
1139 				}
1140 			}
1141 			/*
1142 			** Initially we're assumed to be in standard time.
1143 			*/
1144 			isdst = FALSE;
1145 			theiroffset = theirstdoffset;
1146 			/*
1147 			** Now juggle transition times and types
1148 			** tracking offsets as you do.
1149 			*/
1150 			for (i = 0; i < sp->timecnt; ++i) {
1151 				j = sp->types[i];
1152 				sp->types[i] = sp->ttis[j].tt_isdst;
1153 				if (sp->ttis[j].tt_ttisgmt) {
1154 					/* No adjustment to transition time */
1155 				} else {
1156 					/*
1157 					** If summer time is in effect, and the
1158 					** transition time was not specified as
1159 					** standard time, add the summer time
1160 					** offset to the transition time;
1161 					** otherwise, add the standard time
1162 					** offset to the transition time.
1163 					*/
1164 					/*
1165 					** Transitions from DST to DDST
1166 					** will effectively disappear since
1167 					** POSIX provides for only one DST
1168 					** offset.
1169 					*/
1170 					if (isdst && !sp->ttis[j].tt_ttisstd) {
1171 						sp->ats[i] += dstoffset -
1172 							theirdstoffset;
1173 					} else {
1174 						sp->ats[i] += stdoffset -
1175 							theirstdoffset;
1176 					}
1177 				}
1178 				theiroffset = -sp->ttis[j].tt_gmtoff;
1179 				if (sp->ttis[j].tt_isdst)
1180 					theirdstoffset = theiroffset;
1181 				else	theirstdoffset = theiroffset;
1182 			}
1183 			/*
1184 			** Finally, fill in ttis.
1185 			** ttisstd and ttisgmt need not be handled.
1186 			*/
1187 			sp->ttis[0].tt_gmtoff = -stdoffset;
1188 			sp->ttis[0].tt_isdst = FALSE;
1189 			sp->ttis[0].tt_abbrind = 0;
1190 			sp->ttis[1].tt_gmtoff = -dstoffset;
1191 			sp->ttis[1].tt_isdst = TRUE;
1192 			sp->ttis[1].tt_abbrind = stdlen + 1;
1193 			sp->typecnt = 2;
1194 		}
1195 	} else {
1196 		dstlen = 0;
1197 		sp->typecnt = 1;		/* only standard time */
1198 		sp->timecnt = 0;
1199 		sp->ttis[0].tt_gmtoff = -stdoffset;
1200 		sp->ttis[0].tt_isdst = 0;
1201 		sp->ttis[0].tt_abbrind = 0;
1202 	}
1203 	sp->charcnt = stdlen + 1;
1204 	if (dstlen != 0)
1205 		sp->charcnt += dstlen + 1;
1206 	if ((size_t) sp->charcnt > sizeof sp->chars)
1207 		return -1;
1208 	cp = sp->chars;
1209 	(void) strncpy(cp, stdname, stdlen);
1210 	cp += stdlen;
1211 	*cp++ = '\0';
1212 	if (dstlen != 0) {
1213 		(void) strncpy(cp, dstname, dstlen);
1214 		*(cp + dstlen) = '\0';
1215 	}
1216 	return 0;
1217 }
1218 
1219 static void
gmtload(sp)1220 gmtload(sp)
1221 struct state * const	sp;
1222 {
1223 	if (tzload(gmt, sp, TRUE) != 0)
1224 		(void) tzparse(gmt, sp, TRUE);
1225 }
1226 
1227 static void
tzsetwall_basic(int rdlocked)1228 tzsetwall_basic(int rdlocked)
1229 {
1230 	if (!rdlocked)
1231 		_RWLOCK_RDLOCK(&lcl_rwlock);
1232 	if (lcl_is_set < 0) {
1233 		if (!rdlocked)
1234 			_RWLOCK_UNLOCK(&lcl_rwlock);
1235 		return;
1236 	}
1237 	_RWLOCK_UNLOCK(&lcl_rwlock);
1238 
1239 	_RWLOCK_WRLOCK(&lcl_rwlock);
1240 	lcl_is_set = -1;
1241 
1242 #ifdef ALL_STATE
1243 	if (lclptr == NULL) {
1244 		lclptr = (struct state *) calloc(1, sizeof *lclptr);
1245 		if (lclptr == NULL) {
1246 			settzname();	/* all we can do */
1247 			_RWLOCK_UNLOCK(&lcl_rwlock);
1248 			if (rdlocked)
1249 				_RWLOCK_RDLOCK(&lcl_rwlock);
1250 			return;
1251 		}
1252 	}
1253 #endif /* defined ALL_STATE */
1254 	if (tzload((char *) NULL, lclptr, TRUE) != 0)
1255 		gmtload(lclptr);
1256 	settzname();
1257 	_RWLOCK_UNLOCK(&lcl_rwlock);
1258 
1259 	if (rdlocked)
1260 		_RWLOCK_RDLOCK(&lcl_rwlock);
1261 }
1262 
1263 void
tzsetwall(void)1264 tzsetwall(void)
1265 {
1266 	tzsetwall_basic(0);
1267 }
1268 
1269 static void
tzset_basic(int rdlocked)1270 tzset_basic(int rdlocked)
1271 {
1272 	const char *	name;
1273 
1274 	name = getenv("TZ");
1275 	if (name == NULL) {
1276 		tzsetwall_basic(rdlocked);
1277 		return;
1278 	}
1279 
1280 	if (!rdlocked)
1281 		_RWLOCK_RDLOCK(&lcl_rwlock);
1282 	if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) {
1283 		if (!rdlocked)
1284 			_RWLOCK_UNLOCK(&lcl_rwlock);
1285 		return;
1286 	}
1287 	_RWLOCK_UNLOCK(&lcl_rwlock);
1288 
1289 	_RWLOCK_WRLOCK(&lcl_rwlock);
1290 	lcl_is_set = strlen(name) < sizeof lcl_TZname;
1291 	if (lcl_is_set)
1292 		(void) strcpy(lcl_TZname, name);
1293 
1294 #ifdef ALL_STATE
1295 	if (lclptr == NULL) {
1296 		lclptr = (struct state *) calloc(1, sizeof *lclptr);
1297 		if (lclptr == NULL) {
1298 			settzname();	/* all we can do */
1299 			_RWLOCK_UNLOCK(&lcl_rwlock);
1300 			if (rdlocked)
1301 				_RWLOCK_RDLOCK(&lcl_rwlock);
1302 			return;
1303 		}
1304 	}
1305 #endif /* defined ALL_STATE */
1306 	if (*name == '\0') {
1307 		/*
1308 		** User wants it fast rather than right.
1309 		*/
1310 		lclptr->leapcnt = 0;		/* so, we're off a little */
1311 		lclptr->timecnt = 0;
1312 		lclptr->typecnt = 0;
1313 		lclptr->ttis[0].tt_isdst = 0;
1314 		lclptr->ttis[0].tt_gmtoff = 0;
1315 		lclptr->ttis[0].tt_abbrind = 0;
1316 		(void) strcpy(lclptr->chars, gmt);
1317 	} else if (tzload(name, lclptr, TRUE) != 0)
1318 		if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0)
1319 			(void) gmtload(lclptr);
1320 	settzname();
1321 	_RWLOCK_UNLOCK(&lcl_rwlock);
1322 
1323 	if (rdlocked)
1324 		_RWLOCK_RDLOCK(&lcl_rwlock);
1325 }
1326 
1327 void
tzset(void)1328 tzset(void)
1329 {
1330 	tzset_basic(0);
1331 }
1332 
1333 /*
1334 ** The easy way to behave "as if no library function calls" localtime
1335 ** is to not call it--so we drop its guts into "localsub", which can be
1336 ** freely called. (And no, the PANS doesn't require the above behavior--
1337 ** but it *is* desirable.)
1338 **
1339 ** The unused offset argument is for the benefit of mktime variants.
1340 */
1341 
1342 /*ARGSUSED*/
1343 static struct tm *
localsub(timep,offset,tmp)1344 localsub(timep, offset, tmp)
1345 const time_t * const	timep;
1346 const long		offset;
1347 struct tm * const	tmp;
1348 {
1349 	struct state *		sp;
1350 	const struct ttinfo *	ttisp;
1351 	int			i;
1352 	struct tm *		result;
1353 	const time_t		t = *timep;
1354 
1355 	sp = lclptr;
1356 #ifdef ALL_STATE
1357 	if (sp == NULL)
1358 		return gmtsub(timep, offset, tmp);
1359 #endif /* defined ALL_STATE */
1360 	if ((sp->goback && t < sp->ats[0]) ||
1361 		(sp->goahead && t > sp->ats[sp->timecnt - 1])) {
1362 			time_t			newt = t;
1363 			register time_t		seconds;
1364 			register time_t		tcycles;
1365 			register int_fast64_t	icycles;
1366 
1367 			if (t < sp->ats[0])
1368 				seconds = sp->ats[0] - t;
1369 			else	seconds = t - sp->ats[sp->timecnt - 1];
1370 			--seconds;
1371 			tcycles = seconds / YEARSPERREPEAT / AVGSECSPERYEAR;
1372 			++tcycles;
1373 			icycles = tcycles;
1374 			if (tcycles - icycles >= 1 || icycles - tcycles >= 1)
1375 				return NULL;
1376 			seconds = icycles;
1377 			seconds *= YEARSPERREPEAT;
1378 			seconds *= AVGSECSPERYEAR;
1379 			if (t < sp->ats[0])
1380 				newt += seconds;
1381 			else	newt -= seconds;
1382 			if (newt < sp->ats[0] ||
1383 				newt > sp->ats[sp->timecnt - 1])
1384 					return NULL;	/* "cannot happen" */
1385 			result = localsub(&newt, offset, tmp);
1386 			if (result == tmp) {
1387 				register time_t	newy;
1388 
1389 				newy = tmp->tm_year;
1390 				if (t < sp->ats[0])
1391 					newy -= icycles * YEARSPERREPEAT;
1392 				else	newy += icycles * YEARSPERREPEAT;
1393 				tmp->tm_year = newy;
1394 				if (tmp->tm_year != newy)
1395 					return NULL;
1396 			}
1397 			return result;
1398 	}
1399 	if (sp->timecnt == 0 || t < sp->ats[0]) {
1400 		i = 0;
1401 		while (sp->ttis[i].tt_isdst)
1402 			if (++i >= sp->typecnt) {
1403 				i = 0;
1404 				break;
1405 			}
1406 	} else {
1407 		register int	lo = 1;
1408 		register int	hi = sp->timecnt;
1409 
1410 		while (lo < hi) {
1411 			register int	mid = (lo + hi) >> 1;
1412 
1413 			if (t < sp->ats[mid])
1414 				hi = mid;
1415 			else	lo = mid + 1;
1416 		}
1417 		i = (int) sp->types[lo - 1];
1418 	}
1419 	ttisp = &sp->ttis[i];
1420 	/*
1421 	** To get (wrong) behavior that's compatible with System V Release 2.0
1422 	** you'd replace the statement below with
1423 	**	t += ttisp->tt_gmtoff;
1424 	**	timesub(&t, 0L, sp, tmp);
1425 	*/
1426 	result = timesub(&t, ttisp->tt_gmtoff, sp, tmp);
1427 	tmp->tm_isdst = ttisp->tt_isdst;
1428 	tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind];
1429 #ifdef TM_ZONE
1430 	tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind];
1431 #endif /* defined TM_ZONE */
1432 	return result;
1433 }
1434 
1435 static void
localtime_key_init(void)1436 localtime_key_init(void)
1437 {
1438 
1439 	localtime_key_error = _pthread_key_create(&localtime_key, free);
1440 }
1441 
1442 struct tm *
localtime(timep)1443 localtime(timep)
1444 const time_t * const	timep;
1445 {
1446 	struct tm *p_tm;
1447 
1448 	if (__isthreaded != 0) {
1449 		_pthread_once(&localtime_once, localtime_key_init);
1450 		if (localtime_key_error != 0) {
1451 			errno = localtime_key_error;
1452 			return(NULL);
1453 		}
1454 		p_tm = _pthread_getspecific(localtime_key);
1455 		if (p_tm == NULL) {
1456 			if ((p_tm = (struct tm *)malloc(sizeof(struct tm)))
1457 			    == NULL)
1458 				return(NULL);
1459 			_pthread_setspecific(localtime_key, p_tm);
1460 		}
1461 		_RWLOCK_RDLOCK(&lcl_rwlock);
1462 		tzset_basic(1);
1463 		localsub(timep, 0L, p_tm);
1464 		_RWLOCK_UNLOCK(&lcl_rwlock);
1465 		return(p_tm);
1466 	} else {
1467 		tzset_basic(0);
1468 		localsub(timep, 0L, &tm);
1469 		return(&tm);
1470 	}
1471 }
1472 
1473 /*
1474 ** Re-entrant version of localtime.
1475 */
1476 
1477 struct tm *
localtime_r(timep,tmp)1478 localtime_r(timep, tmp)
1479 const time_t * const	timep;
1480 struct tm *		tmp;
1481 {
1482 	_RWLOCK_RDLOCK(&lcl_rwlock);
1483 	tzset_basic(1);
1484 	localsub(timep, 0L, tmp);
1485 	_RWLOCK_UNLOCK(&lcl_rwlock);
1486 	return tmp;
1487 }
1488 
1489 static void
gmt_init(void)1490 gmt_init(void)
1491 {
1492 
1493 #ifdef ALL_STATE
1494 	gmtptr = (struct state *) calloc(1, sizeof *gmtptr);
1495 	if (gmtptr != NULL)
1496 #endif /* defined ALL_STATE */
1497 		gmtload(gmtptr);
1498 }
1499 
1500 /*
1501 ** gmtsub is to gmtime as localsub is to localtime.
1502 */
1503 
1504 static struct tm *
gmtsub(timep,offset,tmp)1505 gmtsub(timep, offset, tmp)
1506 const time_t * const	timep;
1507 const long		offset;
1508 struct tm * const	tmp;
1509 {
1510 	register struct tm *	result;
1511 
1512 	_once(&gmt_once, gmt_init);
1513 	result = timesub(timep, offset, gmtptr, tmp);
1514 #ifdef TM_ZONE
1515 	/*
1516 	** Could get fancy here and deliver something such as
1517 	** "UTC+xxxx" or "UTC-xxxx" if offset is non-zero,
1518 	** but this is no time for a treasure hunt.
1519 	*/
1520 	if (offset != 0)
1521 		tmp->TM_ZONE = wildabbr;
1522 	else {
1523 #ifdef ALL_STATE
1524 		if (gmtptr == NULL)
1525 			tmp->TM_ZONE = gmt;
1526 		else	tmp->TM_ZONE = gmtptr->chars;
1527 #endif /* defined ALL_STATE */
1528 #ifndef ALL_STATE
1529 		tmp->TM_ZONE = gmtptr->chars;
1530 #endif /* State Farm */
1531 	}
1532 #endif /* defined TM_ZONE */
1533 	return result;
1534 }
1535 
1536 static void
gmtime_key_init(void)1537 gmtime_key_init(void)
1538 {
1539 
1540 	gmtime_key_error = _pthread_key_create(&gmtime_key, free);
1541 }
1542 
1543 struct tm *
gmtime(timep)1544 gmtime(timep)
1545 const time_t * const	timep;
1546 {
1547 	struct tm *p_tm;
1548 
1549 	if (__isthreaded != 0) {
1550 		_pthread_once(&gmtime_once, gmtime_key_init);
1551 		if (gmtime_key_error != 0) {
1552 			errno = gmtime_key_error;
1553 			return(NULL);
1554 		}
1555 		/*
1556 		 * Changed to follow POSIX.1 threads standard, which
1557 		 * is what BSD currently has.
1558 		 */
1559 		if ((p_tm = _pthread_getspecific(gmtime_key)) == NULL) {
1560 			if ((p_tm = (struct tm *)malloc(sizeof(struct tm)))
1561 			    == NULL) {
1562 				return(NULL);
1563 			}
1564 			_pthread_setspecific(gmtime_key, p_tm);
1565 		}
1566 		gmtsub(timep, 0L, p_tm);
1567 		return(p_tm);
1568 	}
1569 	else {
1570 		gmtsub(timep, 0L, &tm);
1571 		return(&tm);
1572 	}
1573 }
1574 
1575 /*
1576 * Re-entrant version of gmtime.
1577 */
1578 
1579 struct tm *
gmtime_r(timep,tmp)1580 gmtime_r(timep, tmp)
1581 const time_t * const	timep;
1582 struct tm *		tmp;
1583 {
1584 	return gmtsub(timep, 0L, tmp);
1585 }
1586 
1587 #ifdef STD_INSPIRED
1588 
1589 struct tm *
offtime(timep,offset)1590 offtime(timep, offset)
1591 const time_t * const	timep;
1592 const long		offset;
1593 {
1594 	return gmtsub(timep, offset, &tm);
1595 }
1596 
1597 #endif /* defined STD_INSPIRED */
1598 
1599 /*
1600 ** Return the number of leap years through the end of the given year
1601 ** where, to make the math easy, the answer for year zero is defined as zero.
1602 */
1603 
1604 static int
leaps_thru_end_of(y)1605 leaps_thru_end_of(y)
1606 register const int	y;
1607 {
1608 	return (y >= 0) ? (y / 4 - y / 100 + y / 400) :
1609 		-(leaps_thru_end_of(-(y + 1)) + 1);
1610 }
1611 
1612 static struct tm *
timesub(timep,offset,sp,tmp)1613 timesub(timep, offset, sp, tmp)
1614 const time_t * const			timep;
1615 const long				offset;
1616 const struct state * const	sp;
1617 struct tm * const		tmp;
1618 {
1619 	const struct lsinfo *	lp;
1620 	time_t			tdays;
1621 	int			idays;	/* unsigned would be so 2003 */
1622 	long			rem;
1623 	int			y;
1624 	const int *		ip;
1625 	long			corr;
1626 	int			hit;
1627 	int			i;
1628 
1629 	corr = 0;
1630 	hit = 0;
1631 #ifdef ALL_STATE
1632 	i = (sp == NULL) ? 0 : sp->leapcnt;
1633 #endif /* defined ALL_STATE */
1634 #ifndef ALL_STATE
1635 	i = sp->leapcnt;
1636 #endif /* State Farm */
1637 	while (--i >= 0) {
1638 		lp = &sp->lsis[i];
1639 		if (*timep >= lp->ls_trans) {
1640 			if (*timep == lp->ls_trans) {
1641 				hit = ((i == 0 && lp->ls_corr > 0) ||
1642 					lp->ls_corr > sp->lsis[i - 1].ls_corr);
1643 				if (hit)
1644 					while (i > 0 &&
1645 						sp->lsis[i].ls_trans ==
1646 						sp->lsis[i - 1].ls_trans + 1 &&
1647 						sp->lsis[i].ls_corr ==
1648 						sp->lsis[i - 1].ls_corr + 1) {
1649 							++hit;
1650 							--i;
1651 					}
1652 			}
1653 			corr = lp->ls_corr;
1654 			break;
1655 		}
1656 	}
1657 	y = EPOCH_YEAR;
1658 	tdays = *timep / SECSPERDAY;
1659 	rem = *timep - tdays * SECSPERDAY;
1660 	while (tdays < 0 || tdays >= year_lengths[isleap(y)]) {
1661 		int		newy;
1662 		register time_t	tdelta;
1663 		register int	idelta;
1664 		register int	leapdays;
1665 
1666 		tdelta = tdays / DAYSPERLYEAR;
1667 		idelta = tdelta;
1668 		if (tdelta - idelta >= 1 || idelta - tdelta >= 1)
1669 			return NULL;
1670 		if (idelta == 0)
1671 			idelta = (tdays < 0) ? -1 : 1;
1672 		newy = y;
1673 		if (increment_overflow(&newy, idelta))
1674 			return NULL;
1675 		leapdays = leaps_thru_end_of(newy - 1) -
1676 			leaps_thru_end_of(y - 1);
1677 		tdays -= ((time_t) newy - y) * DAYSPERNYEAR;
1678 		tdays -= leapdays;
1679 		y = newy;
1680 	}
1681 	{
1682 		register long	seconds;
1683 
1684 		seconds = tdays * SECSPERDAY + 0.5;
1685 		tdays = seconds / SECSPERDAY;
1686 		rem += seconds - tdays * SECSPERDAY;
1687 	}
1688 	/*
1689 	** Given the range, we can now fearlessly cast...
1690 	*/
1691 	idays = tdays;
1692 	rem += offset - corr;
1693 	while (rem < 0) {
1694 		rem += SECSPERDAY;
1695 		--idays;
1696 	}
1697 	while (rem >= SECSPERDAY) {
1698 		rem -= SECSPERDAY;
1699 		++idays;
1700 	}
1701 	while (idays < 0) {
1702 		if (increment_overflow(&y, -1))
1703 			return NULL;
1704 		idays += year_lengths[isleap(y)];
1705 	}
1706 	while (idays >= year_lengths[isleap(y)]) {
1707 		idays -= year_lengths[isleap(y)];
1708 		if (increment_overflow(&y, 1))
1709 			return NULL;
1710 	}
1711 	tmp->tm_year = y;
1712 	if (increment_overflow(&tmp->tm_year, -TM_YEAR_BASE))
1713 		return NULL;
1714 	tmp->tm_yday = idays;
1715 	/*
1716 	** The "extra" mods below avoid overflow problems.
1717 	*/
1718 	tmp->tm_wday = EPOCH_WDAY +
1719 		((y - EPOCH_YEAR) % DAYSPERWEEK) *
1720 		(DAYSPERNYEAR % DAYSPERWEEK) +
1721 		leaps_thru_end_of(y - 1) -
1722 		leaps_thru_end_of(EPOCH_YEAR - 1) +
1723 		idays;
1724 	tmp->tm_wday %= DAYSPERWEEK;
1725 	if (tmp->tm_wday < 0)
1726 		tmp->tm_wday += DAYSPERWEEK;
1727 	tmp->tm_hour = (int) (rem / SECSPERHOUR);
1728 	rem %= SECSPERHOUR;
1729 	tmp->tm_min = (int) (rem / SECSPERMIN);
1730 	/*
1731 	** A positive leap second requires a special
1732 	** representation. This uses "... ??:59:60" et seq.
1733 	*/
1734 	tmp->tm_sec = (int) (rem % SECSPERMIN) + hit;
1735 	ip = mon_lengths[isleap(y)];
1736 	for (tmp->tm_mon = 0; idays >= ip[tmp->tm_mon]; ++(tmp->tm_mon))
1737 		idays -= ip[tmp->tm_mon];
1738 	tmp->tm_mday = (int) (idays + 1);
1739 	tmp->tm_isdst = 0;
1740 #ifdef TM_GMTOFF
1741 	tmp->TM_GMTOFF = offset;
1742 #endif /* defined TM_GMTOFF */
1743 	return tmp;
1744 }
1745 
1746 char *
ctime(timep)1747 ctime(timep)
1748 const time_t * const	timep;
1749 {
1750 /*
1751 ** Section 4.12.3.2 of X3.159-1989 requires that
1752 **	The ctime function converts the calendar time pointed to by timer
1753 **	to local time in the form of a string. It is equivalent to
1754 **		asctime(localtime(timer))
1755 */
1756 	return asctime(localtime(timep));
1757 }
1758 
1759 char *
ctime_r(timep,buf)1760 ctime_r(timep, buf)
1761 const time_t * const	timep;
1762 char *			buf;
1763 {
1764 	struct tm	mytm;
1765 
1766 	return asctime_r(localtime_r(timep, &mytm), buf);
1767 }
1768 
1769 /*
1770 ** Adapted from code provided by Robert Elz, who writes:
1771 **	The "best" way to do mktime I think is based on an idea of Bob
1772 **	Kridle's (so its said...) from a long time ago.
1773 **	It does a binary search of the time_t space. Since time_t's are
1774 **	just 32 bits, its a max of 32 iterations (even at 64 bits it
1775 **	would still be very reasonable).
1776 */
1777 
1778 #ifndef WRONG
1779 #define WRONG	(-1)
1780 #endif /* !defined WRONG */
1781 
1782 /*
1783 ** Simplified normalize logic courtesy Paul Eggert.
1784 */
1785 
1786 static int
increment_overflow(number,delta)1787 increment_overflow(number, delta)
1788 int *	number;
1789 int	delta;
1790 {
1791 	int	number0;
1792 
1793 	number0 = *number;
1794 	*number += delta;
1795 	return (*number < number0) != (delta < 0);
1796 }
1797 
1798 static int
long_increment_overflow(number,delta)1799 long_increment_overflow(number, delta)
1800 long *	number;
1801 int	delta;
1802 {
1803 	long	number0;
1804 
1805 	number0 = *number;
1806 	*number += delta;
1807 	return (*number < number0) != (delta < 0);
1808 }
1809 
1810 static int
normalize_overflow(tensptr,unitsptr,base)1811 normalize_overflow(tensptr, unitsptr, base)
1812 int * const	tensptr;
1813 int * const	unitsptr;
1814 const int	base;
1815 {
1816 	int	tensdelta;
1817 
1818 	tensdelta = (*unitsptr >= 0) ?
1819 		(*unitsptr / base) :
1820 		(-1 - (-1 - *unitsptr) / base);
1821 	*unitsptr -= tensdelta * base;
1822 	return increment_overflow(tensptr, tensdelta);
1823 }
1824 
1825 static int
long_normalize_overflow(tensptr,unitsptr,base)1826 long_normalize_overflow(tensptr, unitsptr, base)
1827 long * const	tensptr;
1828 int * const	unitsptr;
1829 const int	base;
1830 {
1831 	register int	tensdelta;
1832 
1833 	tensdelta = (*unitsptr >= 0) ?
1834 		(*unitsptr / base) :
1835 		(-1 - (-1 - *unitsptr) / base);
1836 	*unitsptr -= tensdelta * base;
1837 	return long_increment_overflow(tensptr, tensdelta);
1838 }
1839 
1840 static int
tmcomp(atmp,btmp)1841 tmcomp(atmp, btmp)
1842 const struct tm * const atmp;
1843 const struct tm * const btmp;
1844 {
1845 	int	result;
1846 
1847 	if ((result = (atmp->tm_year - btmp->tm_year)) == 0 &&
1848 		(result = (atmp->tm_mon - btmp->tm_mon)) == 0 &&
1849 		(result = (atmp->tm_mday - btmp->tm_mday)) == 0 &&
1850 		(result = (atmp->tm_hour - btmp->tm_hour)) == 0 &&
1851 		(result = (atmp->tm_min - btmp->tm_min)) == 0)
1852 			result = atmp->tm_sec - btmp->tm_sec;
1853 	return result;
1854 }
1855 
1856 static time_t
time2sub(tmp,funcp,offset,okayp,do_norm_secs)1857 time2sub(tmp, funcp, offset, okayp, do_norm_secs)
1858 struct tm * const	tmp;
1859 struct tm * (* const	funcp)(const time_t*, long, struct tm*);
1860 const long		offset;
1861 int * const		okayp;
1862 const int		do_norm_secs;
1863 {
1864 	const struct state *	sp;
1865 	int			dir;
1866 	int			i, j;
1867 	int			saved_seconds;
1868 	long			li;
1869 	time_t			lo;
1870 	time_t			hi;
1871 	long			y;
1872 	time_t			newt;
1873 	time_t			t;
1874 	struct tm		yourtm, mytm;
1875 
1876 	*okayp = FALSE;
1877 	yourtm = *tmp;
1878 	if (do_norm_secs) {
1879 		if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec,
1880 			SECSPERMIN))
1881 				return WRONG;
1882 	}
1883 	if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR))
1884 		return WRONG;
1885 	if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY))
1886 		return WRONG;
1887 	y = yourtm.tm_year;
1888 	if (long_normalize_overflow(&y, &yourtm.tm_mon, MONSPERYEAR))
1889 		return WRONG;
1890 	/*
1891 	** Turn y into an actual year number for now.
1892 	** It is converted back to an offset from TM_YEAR_BASE later.
1893 	*/
1894 	if (long_increment_overflow(&y, TM_YEAR_BASE))
1895 		return WRONG;
1896 	while (yourtm.tm_mday <= 0) {
1897 		if (long_increment_overflow(&y, -1))
1898 			return WRONG;
1899 		li = y + (1 < yourtm.tm_mon);
1900 		yourtm.tm_mday += year_lengths[isleap(li)];
1901 	}
1902 	while (yourtm.tm_mday > DAYSPERLYEAR) {
1903 		li = y + (1 < yourtm.tm_mon);
1904 		yourtm.tm_mday -= year_lengths[isleap(li)];
1905 		if (long_increment_overflow(&y, 1))
1906 			return WRONG;
1907 	}
1908 	for ( ; ; ) {
1909 		i = mon_lengths[isleap(y)][yourtm.tm_mon];
1910 		if (yourtm.tm_mday <= i)
1911 			break;
1912 		yourtm.tm_mday -= i;
1913 		if (++yourtm.tm_mon >= MONSPERYEAR) {
1914 			yourtm.tm_mon = 0;
1915 			if (long_increment_overflow(&y, 1))
1916 				return WRONG;
1917 		}
1918 	}
1919 	if (long_increment_overflow(&y, -TM_YEAR_BASE))
1920 		return WRONG;
1921 	yourtm.tm_year = y;
1922 	if (yourtm.tm_year != y)
1923 		return WRONG;
1924 	/* Don't go below 1900 for POLA */
1925 	if (yourtm.tm_year < 0)
1926 		return WRONG;
1927 	if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN)
1928 		saved_seconds = 0;
1929 	else if (y + TM_YEAR_BASE < EPOCH_YEAR) {
1930 		/*
1931 		** We can't set tm_sec to 0, because that might push the
1932 		** time below the minimum representable time.
1933 		** Set tm_sec to 59 instead.
1934 		** This assumes that the minimum representable time is
1935 		** not in the same minute that a leap second was deleted from,
1936 		** which is a safer assumption than using 58 would be.
1937 		*/
1938 		if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN))
1939 			return WRONG;
1940 		saved_seconds = yourtm.tm_sec;
1941 		yourtm.tm_sec = SECSPERMIN - 1;
1942 	} else {
1943 		saved_seconds = yourtm.tm_sec;
1944 		yourtm.tm_sec = 0;
1945 	}
1946 	/*
1947 	** Do a binary search (this works whatever time_t's type is).
1948 	*/
1949 	if (!TYPE_SIGNED(time_t)) {
1950 		lo = 0;
1951 		hi = lo - 1;
1952 	} else if (!TYPE_INTEGRAL(time_t)) {
1953 		if (sizeof(time_t) > sizeof(float))
1954 			hi = (time_t) DBL_MAX;
1955 		else	hi = (time_t) FLT_MAX;
1956 		lo = -hi;
1957 	} else {
1958 		lo = 1;
1959 		for (i = 0; i < (int) TYPE_BIT(time_t) - 1; ++i)
1960 			lo *= 2;
1961 		hi = -(lo + 1);
1962 	}
1963 	for ( ; ; ) {
1964 		t = lo / 2 + hi / 2;
1965 		if (t < lo)
1966 			t = lo;
1967 		else if (t > hi)
1968 			t = hi;
1969 		if ((*funcp)(&t, offset, &mytm) == NULL) {
1970 			/*
1971 			** Assume that t is too extreme to be represented in
1972 			** a struct tm; arrange things so that it is less
1973 			** extreme on the next pass.
1974 			*/
1975 			dir = (t > 0) ? 1 : -1;
1976 		} else	dir = tmcomp(&mytm, &yourtm);
1977 		if (dir != 0) {
1978 			if (t == lo) {
1979 				++t;
1980 				if (t <= lo)
1981 					return WRONG;
1982 				++lo;
1983 			} else if (t == hi) {
1984 				--t;
1985 				if (t >= hi)
1986 					return WRONG;
1987 				--hi;
1988 			}
1989 			if (lo > hi)
1990 				return WRONG;
1991 			if (dir > 0)
1992 				hi = t;
1993 			else	lo = t;
1994 			continue;
1995 		}
1996 		if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst)
1997 			break;
1998 		/*
1999 		** Right time, wrong type.
2000 		** Hunt for right time, right type.
2001 		** It's okay to guess wrong since the guess
2002 		** gets checked.
2003 		*/
2004 		sp = (const struct state *)
2005 			((funcp == localsub) ? lclptr : gmtptr);
2006 #ifdef ALL_STATE
2007 		if (sp == NULL)
2008 			return WRONG;
2009 #endif /* defined ALL_STATE */
2010 		for (i = sp->typecnt - 1; i >= 0; --i) {
2011 			if (sp->ttis[i].tt_isdst != yourtm.tm_isdst)
2012 				continue;
2013 			for (j = sp->typecnt - 1; j >= 0; --j) {
2014 				if (sp->ttis[j].tt_isdst == yourtm.tm_isdst)
2015 					continue;
2016 				newt = t + sp->ttis[j].tt_gmtoff -
2017 					sp->ttis[i].tt_gmtoff;
2018 				if ((*funcp)(&newt, offset, &mytm) == NULL)
2019 					continue;
2020 				if (tmcomp(&mytm, &yourtm) != 0)
2021 					continue;
2022 				if (mytm.tm_isdst != yourtm.tm_isdst)
2023 					continue;
2024 				/*
2025 				** We have a match.
2026 				*/
2027 				t = newt;
2028 				goto label;
2029 			}
2030 		}
2031 		return WRONG;
2032 	}
2033 label:
2034 	newt = t + saved_seconds;
2035 	if ((newt < t) != (saved_seconds < 0))
2036 		return WRONG;
2037 	t = newt;
2038 	if ((*funcp)(&t, offset, tmp))
2039 		*okayp = TRUE;
2040 	return t;
2041 }
2042 
2043 static time_t
time2(tmp,funcp,offset,okayp)2044 time2(tmp, funcp, offset, okayp)
2045 struct tm * const	tmp;
2046 struct tm * (* const	funcp)(const time_t*, long, struct tm*);
2047 const long		offset;
2048 int * const		okayp;
2049 {
2050 	time_t	t;
2051 
2052 	/*
2053 	** First try without normalization of seconds
2054 	** (in case tm_sec contains a value associated with a leap second).
2055 	** If that fails, try with normalization of seconds.
2056 	*/
2057 	t = time2sub(tmp, funcp, offset, okayp, FALSE);
2058 	return *okayp ? t : time2sub(tmp, funcp, offset, okayp, TRUE);
2059 }
2060 
2061 static time_t
time1(tmp,funcp,offset)2062 time1(tmp, funcp, offset)
2063 struct tm * const	tmp;
2064 struct tm * (* const  funcp)(const time_t *, long, struct tm *);
2065 const long		offset;
2066 {
2067 	time_t			t;
2068 	const struct state *	sp;
2069 	int			samei, otheri;
2070 	int			sameind, otherind;
2071 	int			i;
2072 	int			nseen;
2073 	int				seen[TZ_MAX_TYPES];
2074 	int				types[TZ_MAX_TYPES];
2075 	int				okay;
2076 
2077 	if (tmp == NULL) {
2078 		errno = EINVAL;
2079 		return WRONG;
2080 	}
2081 
2082 	if (tmp->tm_isdst > 1)
2083 		tmp->tm_isdst = 1;
2084 	t = time2(tmp, funcp, offset, &okay);
2085 #ifdef PCTS
2086 	/*
2087 	** PCTS code courtesy Grant Sullivan.
2088 	*/
2089 	if (okay)
2090 		return t;
2091 	if (tmp->tm_isdst < 0)
2092 		tmp->tm_isdst = 0;	/* reset to std and try again */
2093 #endif /* defined PCTS */
2094 #ifndef PCTS
2095 	if (okay || tmp->tm_isdst < 0)
2096 		return t;
2097 #endif /* !defined PCTS */
2098 	/*
2099 	** We're supposed to assume that somebody took a time of one type
2100 	** and did some math on it that yielded a "struct tm" that's bad.
2101 	** We try to divine the type they started from and adjust to the
2102 	** type they need.
2103 	*/
2104 	sp = (const struct state *) ((funcp == localsub) ? lclptr : gmtptr);
2105 #ifdef ALL_STATE
2106 	if (sp == NULL)
2107 		return WRONG;
2108 #endif /* defined ALL_STATE */
2109 	for (i = 0; i < sp->typecnt; ++i)
2110 		seen[i] = FALSE;
2111 	nseen = 0;
2112 	for (i = sp->timecnt - 1; i >= 0; --i)
2113 		if (!seen[sp->types[i]]) {
2114 			seen[sp->types[i]] = TRUE;
2115 			types[nseen++] = sp->types[i];
2116 		}
2117 	for (sameind = 0; sameind < nseen; ++sameind) {
2118 		samei = types[sameind];
2119 		if (sp->ttis[samei].tt_isdst != tmp->tm_isdst)
2120 			continue;
2121 		for (otherind = 0; otherind < nseen; ++otherind) {
2122 			otheri = types[otherind];
2123 			if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst)
2124 				continue;
2125 			tmp->tm_sec += sp->ttis[otheri].tt_gmtoff -
2126 					sp->ttis[samei].tt_gmtoff;
2127 			tmp->tm_isdst = !tmp->tm_isdst;
2128 			t = time2(tmp, funcp, offset, &okay);
2129 			if (okay)
2130 				return t;
2131 			tmp->tm_sec -= sp->ttis[otheri].tt_gmtoff -
2132 					sp->ttis[samei].tt_gmtoff;
2133 			tmp->tm_isdst = !tmp->tm_isdst;
2134 		}
2135 	}
2136 	return WRONG;
2137 }
2138 
2139 time_t
mktime(tmp)2140 mktime(tmp)
2141 struct tm * const	tmp;
2142 {
2143 	time_t mktime_return_value;
2144 	_RWLOCK_RDLOCK(&lcl_rwlock);
2145 	tzset_basic(1);
2146 	mktime_return_value = time1(tmp, localsub, 0L);
2147 	_RWLOCK_UNLOCK(&lcl_rwlock);
2148 	return(mktime_return_value);
2149 }
2150 
2151 #ifdef STD_INSPIRED
2152 
2153 time_t
timelocal(tmp)2154 timelocal(tmp)
2155 struct tm * const	tmp;
2156 {
2157 	if (tmp != NULL)
2158 		tmp->tm_isdst = -1;	/* in case it wasn't initialized */
2159 	return mktime(tmp);
2160 }
2161 
2162 time_t
timegm(tmp)2163 timegm(tmp)
2164 struct tm * const	tmp;
2165 {
2166 	if (tmp != NULL)
2167 		tmp->tm_isdst = 0;
2168 	return time1(tmp, gmtsub, 0L);
2169 }
2170 
2171 time_t
timeoff(tmp,offset)2172 timeoff(tmp, offset)
2173 struct tm * const	tmp;
2174 const long		offset;
2175 {
2176 	if (tmp != NULL)
2177 		tmp->tm_isdst = 0;
2178 	return time1(tmp, gmtsub, offset);
2179 }
2180 
2181 #endif /* defined STD_INSPIRED */
2182 
2183 #ifdef CMUCS
2184 
2185 /*
2186 ** The following is supplied for compatibility with
2187 ** previous versions of the CMUCS runtime library.
2188 */
2189 
2190 long
gtime(tmp)2191 gtime(tmp)
2192 struct tm * const	tmp;
2193 {
2194 	const time_t	t = mktime(tmp);
2195 
2196 	if (t == WRONG)
2197 		return -1;
2198 	return t;
2199 }
2200 
2201 #endif /* defined CMUCS */
2202 
2203 /*
2204 ** XXX--is the below the right way to conditionalize??
2205 */
2206 
2207 #ifdef STD_INSPIRED
2208 
2209 /*
2210 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599
2211 ** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which
2212 ** is not the case if we are accounting for leap seconds.
2213 ** So, we provide the following conversion routines for use
2214 ** when exchanging timestamps with POSIX conforming systems.
2215 */
2216 
2217 static long
leapcorr(timep)2218 leapcorr(timep)
2219 time_t *	timep;
2220 {
2221 	struct state *		sp;
2222 	struct lsinfo *	lp;
2223 	int			i;
2224 
2225 	sp = lclptr;
2226 	i = sp->leapcnt;
2227 	while (--i >= 0) {
2228 		lp = &sp->lsis[i];
2229 		if (*timep >= lp->ls_trans)
2230 			return lp->ls_corr;
2231 	}
2232 	return 0;
2233 }
2234 
2235 time_t
time2posix(t)2236 time2posix(t)
2237 time_t	t;
2238 {
2239 	tzset();
2240 	return t - leapcorr(&t);
2241 }
2242 
2243 time_t
posix2time(t)2244 posix2time(t)
2245 time_t	t;
2246 {
2247 	time_t	x;
2248 	time_t	y;
2249 
2250 	tzset();
2251 	/*
2252 	** For a positive leap second hit, the result
2253 	** is not unique. For a negative leap second
2254 	** hit, the corresponding time doesn't exist,
2255 	** so we return an adjacent second.
2256 	*/
2257 	x = t + leapcorr(&t);
2258 	y = x - leapcorr(&x);
2259 	if (y < t) {
2260 		do {
2261 			x++;
2262 			y = x - leapcorr(&x);
2263 		} while (y < t);
2264 		if (t != y)
2265 			return x - 1;
2266 	} else if (y > t) {
2267 		do {
2268 			--x;
2269 			y = x - leapcorr(&x);
2270 		} while (y > t);
2271 		if (t != y)
2272 			return x + 1;
2273 	}
2274 	return x;
2275 }
2276 
2277 #endif /* defined STD_INSPIRED */
2278