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