localtime.c revision 1.39.20.2 1 /* $NetBSD: localtime.c,v 1.39.20.2 2008/09/18 04:39:23 wrstuden Exp $ */
2
3 /*
4 ** This file is in the public domain, so clarified as of
5 ** 1996-06-05 by Arthur David Olson (arthur_david_olson (at) nih.gov).
6 */
7
8 #include <sys/cdefs.h>
9 #if defined(LIBC_SCCS) && !defined(lint)
10 #if 0
11 static char elsieid[] = "@(#)localtime.c 7.78";
12 #else
13 __RCSID("$NetBSD: localtime.c,v 1.39.20.2 2008/09/18 04:39:23 wrstuden Exp $");
14 #endif
15 #endif /* LIBC_SCCS and not lint */
16
17 /*
18 ** Leap second handling from Bradley White (bww (at) k.gp.cs.cmu.edu).
19 ** POSIX-style TZ environment variable handling from Guy Harris
20 ** (guy (at) auspex.com).
21 */
22
23 /*LINTLIBRARY*/
24
25 #include "namespace.h"
26 #include "private.h"
27 #include "tzfile.h"
28 #include "fcntl.h"
29 #include "reentrant.h"
30
31 #ifdef __weak_alias
32 __weak_alias(ctime_r,_ctime_r)
33 __weak_alias(daylight,_daylight)
34 __weak_alias(gmtime_r,_gmtime_r)
35 __weak_alias(localtime_r,_localtime_r)
36 __weak_alias(offtime,_offtime)
37 __weak_alias(posix2time,_posix2time)
38 __weak_alias(time2posix,_time2posix)
39 __weak_alias(timegm,_timegm)
40 __weak_alias(timelocal,_timelocal)
41 __weak_alias(timeoff,_timeoff)
42 __weak_alias(tzname,_tzname)
43 __weak_alias(tzset,_tzset)
44 __weak_alias(tzsetwall,_tzsetwall)
45 #endif
46
47 /*
48 ** SunOS 4.1.1 headers lack O_BINARY.
49 */
50
51 #ifdef O_BINARY
52 #define OPEN_MODE (O_RDONLY | O_BINARY)
53 #endif /* defined O_BINARY */
54 #ifndef O_BINARY
55 #define OPEN_MODE O_RDONLY
56 #endif /* !defined O_BINARY */
57
58 #ifndef WILDABBR
59 /*
60 ** Someone might make incorrect use of a time zone abbreviation:
61 ** 1. They might reference tzname[0] before calling tzset (explicitly
62 ** or implicitly).
63 ** 2. They might reference tzname[1] before calling tzset (explicitly
64 ** or implicitly).
65 ** 3. They might reference tzname[1] after setting to a time zone
66 ** in which Daylight Saving Time is never observed.
67 ** 4. They might reference tzname[0] after setting to a time zone
68 ** in which Standard Time is never observed.
69 ** 5. They might reference tm.TM_ZONE after calling offtime.
70 ** What's best to do in the above cases is open to debate;
71 ** for now, we just set things up so that in any of the five cases
72 ** WILDABBR is used. Another possibility: initialize tzname[0] to the
73 ** string "tzname[0] used before set", and similarly for the other cases.
74 ** And another: initialize tzname[0] to "ERA", with an explanation in the
75 ** manual page of what this "time zone abbreviation" means (doing this so
76 ** that tzname[0] has the "normal" length of three characters).
77 */
78 #define WILDABBR " "
79 #endif /* !defined WILDABBR */
80
81 static const char wildabbr[] = "WILDABBR";
82
83 static const char gmt[] = "GMT";
84
85 /*
86 ** The DST rules to use if TZ has no rules and we can't load TZDEFRULES.
87 ** We default to US rules as of 1999-08-17.
88 ** POSIX 1003.1 section 8.1.1 says that the default DST rules are
89 ** implementation dependent; for historical reasons, US rules are a
90 ** common default.
91 */
92 #ifndef TZDEFRULESTRING
93 #define TZDEFRULESTRING ",M4.1.0,M10.5.0"
94 #endif /* !defined TZDEFDST */
95
96 struct ttinfo { /* time type information */
97 long tt_gmtoff; /* UTC offset in seconds */
98 int tt_isdst; /* used to set tm_isdst */
99 int tt_abbrind; /* abbreviation list index */
100 int tt_ttisstd; /* TRUE if transition is std time */
101 int tt_ttisgmt; /* TRUE if transition is UTC */
102 };
103
104 struct lsinfo { /* leap second information */
105 time_t ls_trans; /* transition time */
106 long ls_corr; /* correction to apply */
107 };
108
109 #define BIGGEST(a, b) (((a) > (b)) ? (a) : (b))
110
111 #ifdef TZNAME_MAX
112 #define MY_TZNAME_MAX TZNAME_MAX
113 #endif /* defined TZNAME_MAX */
114 #ifndef TZNAME_MAX
115 #define MY_TZNAME_MAX 255
116 #endif /* !defined TZNAME_MAX */
117
118 struct state {
119 int leapcnt;
120 int timecnt;
121 int typecnt;
122 int charcnt;
123 time_t ats[TZ_MAX_TIMES];
124 unsigned char types[TZ_MAX_TIMES];
125 struct ttinfo ttis[TZ_MAX_TYPES];
126 char chars[/*CONSTCOND*/BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt),
127 (2 * (MY_TZNAME_MAX + 1)))];
128 struct lsinfo lsis[TZ_MAX_LEAPS];
129 };
130
131 struct rule {
132 int r_type; /* type of rule--see below */
133 int r_day; /* day number of rule */
134 int r_week; /* week number of rule */
135 int r_mon; /* month number of rule */
136 long r_time; /* transition time of rule */
137 };
138
139 #define JULIAN_DAY 0 /* Jn - Julian day */
140 #define DAY_OF_YEAR 1 /* n - day of year */
141 #define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */
142
143 /*
144 ** Prototypes for static functions.
145 */
146
147 static long detzcode P((const char * codep));
148 static const char * getzname P((const char * strp));
149 static const char * getnum P((const char * strp, int * nump, int min,
150 int max));
151 static const char * getsecs P((const char * strp, long * secsp));
152 static const char * getoffset P((const char * strp, long * offsetp));
153 static const char * getrule P((const char * strp, struct rule * rulep));
154 static void gmtload P((struct state * sp));
155 static void gmtsub P((const time_t * timep, long offset,
156 struct tm * tmp));
157 static void localsub P((const time_t * timep, long offset,
158 struct tm * tmp));
159 static int increment_overflow P((int * number, int delta));
160 static int normalize_overflow P((int * tensptr, int * unitsptr,
161 int base));
162 static void settzname P((void));
163 static time_t time1 P((struct tm * tmp,
164 void(*funcp) P((const time_t *,
165 long, struct tm *)),
166 long offset));
167 static time_t time2 P((struct tm *tmp,
168 void(*funcp) P((const time_t *,
169 long, struct tm*)),
170 long offset, int * okayp));
171 static time_t time2sub P((struct tm *tmp,
172 void(*funcp) P((const time_t *,
173 long, struct tm*)),
174 long offset, int * okayp, int do_norm_secs));
175 static void timesub P((const time_t * timep, long offset,
176 const struct state * sp, struct tm * tmp));
177 static int tmcomp P((const struct tm * atmp,
178 const struct tm * btmp));
179 static time_t transtime P((time_t janfirst, int year,
180 const struct rule * rulep, long offset));
181 static int tzload P((const char * name, struct state * sp));
182 static int tzparse P((const char * name, struct state * sp,
183 int lastditch));
184 static void tzset_unlocked P((void));
185 static void tzsetwall_unlocked P((void));
186 #ifdef STD_INSPIRED
187 static long leapcorr P((time_t * timep));
188 #endif
189
190 #ifdef ALL_STATE
191 static struct state * lclptr;
192 static struct state * gmtptr;
193 #endif /* defined ALL_STATE */
194
195 #ifndef ALL_STATE
196 static struct state lclmem;
197 static struct state gmtmem;
198 #define lclptr (&lclmem)
199 #define gmtptr (&gmtmem)
200 #endif /* State Farm */
201
202 #ifndef TZ_STRLEN_MAX
203 #define TZ_STRLEN_MAX 255
204 #endif /* !defined TZ_STRLEN_MAX */
205
206 static char lcl_TZname[TZ_STRLEN_MAX + 1];
207 static int lcl_is_set;
208 static int gmt_is_set;
209
210 __aconst char * tzname[2] = {
211 (__aconst char *)__UNCONST(wildabbr),
212 (__aconst char *)__UNCONST(wildabbr)
213 };
214
215 #ifdef _REENTRANT
216 static rwlock_t lcl_lock = RWLOCK_INITIALIZER;
217 #endif
218
219 /*
220 ** Section 4.12.3 of X3.159-1989 requires that
221 ** Except for the strftime function, these functions [asctime,
222 ** ctime, gmtime, localtime] return values in one of two static
223 ** objects: a broken-down time structure and an array of char.
224 ** Thanks to Paul Eggert (eggert (at) twinsun.com) for noting this.
225 */
226
227 static struct tm tm;
228
229 #ifdef USG_COMPAT
230 long int timezone = 0;
231 int daylight = 0;
232 #endif /* defined USG_COMPAT */
233
234 #ifdef ALTZONE
235 time_t altzone = 0;
236 #endif /* defined ALTZONE */
237
238 static long
239 detzcode(codep)
240 const char * const codep;
241 {
242 register long result;
243
244 /*
245 ** The first character must be sign extended on systems with >32bit
246 ** longs. This was solved differently in the master tzcode sources
247 ** (the fix first appeared in tzcode95c.tar.gz). But I believe
248 ** that this implementation is superior.
249 */
250
251 #define SIGN_EXTEND_CHAR(x) ((signed char) x)
252
253 result = (SIGN_EXTEND_CHAR(codep[0]) << 24) \
254 | (codep[1] & 0xff) << 16 \
255 | (codep[2] & 0xff) << 8
256 | (codep[3] & 0xff);
257 return result;
258 }
259
260 static void
261 settzname P((void))
262 {
263 register struct state * const sp = lclptr;
264 register int i;
265
266 tzname[0] = (__aconst char *)__UNCONST(wildabbr);
267 tzname[1] = (__aconst char *)__UNCONST(wildabbr);
268 #ifdef USG_COMPAT
269 daylight = 0;
270 timezone = 0;
271 #endif /* defined USG_COMPAT */
272 #ifdef ALTZONE
273 altzone = 0;
274 #endif /* defined ALTZONE */
275 #ifdef ALL_STATE
276 if (sp == NULL) {
277 tzname[0] = tzname[1] = (__aconst char *)__UNCONST(gmt);
278 return;
279 }
280 #endif /* defined ALL_STATE */
281 for (i = 0; i < sp->typecnt; ++i) {
282 register const struct ttinfo * const ttisp = &sp->ttis[i];
283
284 tzname[ttisp->tt_isdst] =
285 &sp->chars[ttisp->tt_abbrind];
286 }
287 /*
288 ** And to get the latest zone names into tzname. . .
289 */
290 for (i = 0; i < sp->timecnt; ++i) {
291 register const struct ttinfo * const ttisp =
292 &sp->ttis[
293 sp->types[i]];
294
295 tzname[ttisp->tt_isdst] =
296 &sp->chars[ttisp->tt_abbrind];
297 #ifdef USG_COMPAT
298 if (ttisp->tt_isdst)
299 daylight = 1;
300 if (i == 0 || !ttisp->tt_isdst)
301 timezone = -(ttisp->tt_gmtoff);
302 #endif /* defined USG_COMPAT */
303 #ifdef ALTZONE
304 if (i == 0 || ttisp->tt_isdst)
305 altzone = -(ttisp->tt_gmtoff);
306 #endif /* defined ALTZONE */
307 }
308 }
309
310 static int
311 tzload(name, sp)
312 register const char * name;
313 register struct state * const sp;
314 {
315 register const char * p;
316 register int i;
317 register int fid;
318
319 if (name == NULL && (name = TZDEFAULT) == NULL)
320 return -1;
321
322 {
323 register int doaccess;
324 /*
325 ** Section 4.9.1 of the C standard says that
326 ** "FILENAME_MAX expands to an integral constant expression
327 ** that is the size needed for an array of char large enough
328 ** to hold the longest file name string that the implementation
329 ** guarantees can be opened."
330 */
331 char fullname[FILENAME_MAX + 1];
332
333 if (name[0] == ':')
334 ++name;
335 doaccess = name[0] == '/';
336 if (!doaccess) {
337 if ((p = TZDIR) == NULL)
338 return -1;
339 if ((strlen(p) + strlen(name) + 1) >= sizeof fullname)
340 return -1;
341 (void) strcpy(fullname, p); /* XXX strcpy is safe */
342 (void) strcat(fullname, "/"); /* XXX strcat is safe */
343 (void) strcat(fullname, name); /* XXX strcat is safe */
344 /*
345 ** Set doaccess if '.' (as in "../") shows up in name.
346 */
347 if (strchr(name, '.') != NULL)
348 doaccess = TRUE;
349 name = fullname;
350 }
351 if (doaccess && access(name, R_OK) != 0)
352 return -1;
353 /*
354 * XXX potential security problem here if user of a set-id
355 * program has set TZ (which is passed in as name) here,
356 * and uses a race condition trick to defeat the access(2)
357 * above.
358 */
359 if ((fid = open(name, OPEN_MODE)) == -1)
360 return -1;
361 }
362 {
363 struct tzhead * tzhp;
364 union {
365 struct tzhead tzhead;
366 char buf[sizeof *sp + sizeof *tzhp];
367 } u;
368 int ttisstdcnt;
369 int ttisgmtcnt;
370
371 i = read(fid, u.buf, sizeof u.buf);
372 if (close(fid) != 0)
373 return -1;
374 ttisstdcnt = (int) detzcode(u.tzhead.tzh_ttisstdcnt);
375 ttisgmtcnt = (int) detzcode(u.tzhead.tzh_ttisgmtcnt);
376 sp->leapcnt = (int) detzcode(u.tzhead.tzh_leapcnt);
377 sp->timecnt = (int) detzcode(u.tzhead.tzh_timecnt);
378 sp->typecnt = (int) detzcode(u.tzhead.tzh_typecnt);
379 sp->charcnt = (int) detzcode(u.tzhead.tzh_charcnt);
380 p = u.tzhead.tzh_charcnt + sizeof u.tzhead.tzh_charcnt;
381 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS ||
382 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES ||
383 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES ||
384 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS ||
385 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) ||
386 (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0))
387 return -1;
388 if (i - (p - u.buf) < sp->timecnt * 4 + /* ats */
389 sp->timecnt + /* types */
390 sp->typecnt * (4 + 2) + /* ttinfos */
391 sp->charcnt + /* chars */
392 sp->leapcnt * (4 + 4) + /* lsinfos */
393 ttisstdcnt + /* ttisstds */
394 ttisgmtcnt) /* ttisgmts */
395 return -1;
396 for (i = 0; i < sp->timecnt; ++i) {
397 sp->ats[i] = detzcode(p);
398 p += 4;
399 }
400 for (i = 0; i < sp->timecnt; ++i) {
401 sp->types[i] = (unsigned char) *p++;
402 if (sp->types[i] >= sp->typecnt)
403 return -1;
404 }
405 for (i = 0; i < sp->typecnt; ++i) {
406 register struct ttinfo * ttisp;
407
408 ttisp = &sp->ttis[i];
409 ttisp->tt_gmtoff = detzcode(p);
410 p += 4;
411 ttisp->tt_isdst = (unsigned char) *p++;
412 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1)
413 return -1;
414 ttisp->tt_abbrind = (unsigned char) *p++;
415 if (ttisp->tt_abbrind < 0 ||
416 ttisp->tt_abbrind > sp->charcnt)
417 return -1;
418 }
419 for (i = 0; i < sp->charcnt; ++i)
420 sp->chars[i] = *p++;
421 sp->chars[i] = '\0'; /* ensure '\0' at end */
422 for (i = 0; i < sp->leapcnt; ++i) {
423 register struct lsinfo * lsisp;
424
425 lsisp = &sp->lsis[i];
426 lsisp->ls_trans = detzcode(p);
427 p += 4;
428 lsisp->ls_corr = detzcode(p);
429 p += 4;
430 }
431 for (i = 0; i < sp->typecnt; ++i) {
432 register struct ttinfo * ttisp;
433
434 ttisp = &sp->ttis[i];
435 if (ttisstdcnt == 0)
436 ttisp->tt_ttisstd = FALSE;
437 else {
438 ttisp->tt_ttisstd = *p++;
439 if (ttisp->tt_ttisstd != TRUE &&
440 ttisp->tt_ttisstd != FALSE)
441 return -1;
442 }
443 }
444 for (i = 0; i < sp->typecnt; ++i) {
445 register struct ttinfo * ttisp;
446
447 ttisp = &sp->ttis[i];
448 if (ttisgmtcnt == 0)
449 ttisp->tt_ttisgmt = FALSE;
450 else {
451 ttisp->tt_ttisgmt = *p++;
452 if (ttisp->tt_ttisgmt != TRUE &&
453 ttisp->tt_ttisgmt != FALSE)
454 return -1;
455 }
456 }
457 }
458 return 0;
459 }
460
461 static const int mon_lengths[2][MONSPERYEAR] = {
462 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
463 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }
464 };
465
466 static const int year_lengths[2] = {
467 DAYSPERNYEAR, DAYSPERLYEAR
468 };
469
470 /*
471 ** Given a pointer into a time zone string, scan until a character that is not
472 ** a valid character in a zone name is found. Return a pointer to that
473 ** character.
474 */
475
476 static const char *
477 getzname(strp)
478 register const char * strp;
479 {
480 register char c;
481
482 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' &&
483 c != '+')
484 ++strp;
485 return strp;
486 }
487
488 /*
489 ** Given a pointer into a time zone string, extract a number from that string.
490 ** Check that the number is within a specified range; if it is not, return
491 ** NULL.
492 ** Otherwise, return a pointer to the first character not part of the number.
493 */
494
495 static const char *
496 getnum(strp, nump, min, max)
497 register const char * strp;
498 int * const nump;
499 const int min;
500 const int max;
501 {
502 register char c;
503 register int num;
504
505 if (strp == NULL || !is_digit(c = *strp))
506 return NULL;
507 num = 0;
508 do {
509 num = num * 10 + (c - '0');
510 if (num > max)
511 return NULL; /* illegal value */
512 c = *++strp;
513 } while (is_digit(c));
514 if (num < min)
515 return NULL; /* illegal value */
516 *nump = num;
517 return strp;
518 }
519
520 /*
521 ** Given a pointer into a time zone string, extract a number of seconds,
522 ** in hh[:mm[:ss]] form, from the string.
523 ** If any error occurs, return NULL.
524 ** Otherwise, return a pointer to the first character not part of the number
525 ** of seconds.
526 */
527
528 static const char *
529 getsecs(strp, secsp)
530 register const char * strp;
531 long * const secsp;
532 {
533 int num;
534
535 /*
536 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like
537 ** "M10.4.6/26", which does not conform to Posix,
538 ** but which specifies the equivalent of
539 ** ``02:00 on the first Sunday on or after 23 Oct''.
540 */
541 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1);
542 if (strp == NULL)
543 return NULL;
544 *secsp = num * (long) SECSPERHOUR;
545 if (*strp == ':') {
546 ++strp;
547 strp = getnum(strp, &num, 0, MINSPERHOUR - 1);
548 if (strp == NULL)
549 return NULL;
550 *secsp += num * SECSPERMIN;
551 if (*strp == ':') {
552 ++strp;
553 /* `SECSPERMIN' allows for leap seconds. */
554 strp = getnum(strp, &num, 0, SECSPERMIN);
555 if (strp == NULL)
556 return NULL;
557 *secsp += num;
558 }
559 }
560 return strp;
561 }
562
563 /*
564 ** Given a pointer into a time zone string, extract an offset, in
565 ** [+-]hh[:mm[:ss]] form, from the string.
566 ** If any error occurs, return NULL.
567 ** Otherwise, return a pointer to the first character not part of the time.
568 */
569
570 static const char *
571 getoffset(strp, offsetp)
572 register const char * strp;
573 long * const offsetp;
574 {
575 register int neg = 0;
576
577 if (*strp == '-') {
578 neg = 1;
579 ++strp;
580 } else if (*strp == '+')
581 ++strp;
582 strp = getsecs(strp, offsetp);
583 if (strp == NULL)
584 return NULL; /* illegal time */
585 if (neg)
586 *offsetp = -*offsetp;
587 return strp;
588 }
589
590 /*
591 ** Given a pointer into a time zone string, extract a rule in the form
592 ** date[/time]. See POSIX section 8 for the format of "date" and "time".
593 ** If a valid rule is not found, return NULL.
594 ** Otherwise, return a pointer to the first character not part of the rule.
595 */
596
597 static const char *
598 getrule(strp, rulep)
599 const char * strp;
600 register struct rule * const rulep;
601 {
602 if (*strp == 'J') {
603 /*
604 ** Julian day.
605 */
606 rulep->r_type = JULIAN_DAY;
607 ++strp;
608 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR);
609 } else if (*strp == 'M') {
610 /*
611 ** Month, week, day.
612 */
613 rulep->r_type = MONTH_NTH_DAY_OF_WEEK;
614 ++strp;
615 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR);
616 if (strp == NULL)
617 return NULL;
618 if (*strp++ != '.')
619 return NULL;
620 strp = getnum(strp, &rulep->r_week, 1, 5);
621 if (strp == NULL)
622 return NULL;
623 if (*strp++ != '.')
624 return NULL;
625 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1);
626 } else if (is_digit(*strp)) {
627 /*
628 ** Day of year.
629 */
630 rulep->r_type = DAY_OF_YEAR;
631 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1);
632 } else return NULL; /* invalid format */
633 if (strp == NULL)
634 return NULL;
635 if (*strp == '/') {
636 /*
637 ** Time specified.
638 */
639 ++strp;
640 strp = getsecs(strp, &rulep->r_time);
641 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */
642 return strp;
643 }
644
645 /*
646 ** Given the Epoch-relative time of January 1, 00:00:00 UTC, in a year, the
647 ** year, a rule, and the offset from UTC at the time that rule takes effect,
648 ** calculate the Epoch-relative time that rule takes effect.
649 */
650
651 static time_t
652 transtime(janfirst, year, rulep, offset)
653 const time_t janfirst;
654 const int year;
655 register const struct rule * const rulep;
656 const long offset;
657 {
658 register int leapyear;
659 register time_t value;
660 register int i;
661 int d, m1, yy0, yy1, yy2, dow;
662
663 INITIALIZE(value);
664 leapyear = isleap(year);
665 switch (rulep->r_type) {
666
667 case JULIAN_DAY:
668 /*
669 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap
670 ** years.
671 ** In non-leap years, or if the day number is 59 or less, just
672 ** add SECSPERDAY times the day number-1 to the time of
673 ** January 1, midnight, to get the day.
674 */
675 value = janfirst + (rulep->r_day - 1) * SECSPERDAY;
676 if (leapyear && rulep->r_day >= 60)
677 value += SECSPERDAY;
678 break;
679
680 case DAY_OF_YEAR:
681 /*
682 ** n - day of year.
683 ** Just add SECSPERDAY times the day number to the time of
684 ** January 1, midnight, to get the day.
685 */
686 value = janfirst + rulep->r_day * SECSPERDAY;
687 break;
688
689 case MONTH_NTH_DAY_OF_WEEK:
690 /*
691 ** Mm.n.d - nth "dth day" of month m.
692 */
693 value = janfirst;
694 for (i = 0; i < rulep->r_mon - 1; ++i)
695 value += mon_lengths[leapyear][i] * SECSPERDAY;
696
697 /*
698 ** Use Zeller's Congruence to get day-of-week of first day of
699 ** month.
700 */
701 m1 = (rulep->r_mon + 9) % 12 + 1;
702 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year;
703 yy1 = yy0 / 100;
704 yy2 = yy0 % 100;
705 dow = ((26 * m1 - 2) / 10 +
706 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7;
707 if (dow < 0)
708 dow += DAYSPERWEEK;
709
710 /*
711 ** "dow" is the day-of-week of the first day of the month. Get
712 ** the day-of-month (zero-origin) of the first "dow" day of the
713 ** month.
714 */
715 d = rulep->r_day - dow;
716 if (d < 0)
717 d += DAYSPERWEEK;
718 for (i = 1; i < rulep->r_week; ++i) {
719 if (d + DAYSPERWEEK >=
720 mon_lengths[leapyear][rulep->r_mon - 1])
721 break;
722 d += DAYSPERWEEK;
723 }
724
725 /*
726 ** "d" is the day-of-month (zero-origin) of the day we want.
727 */
728 value += d * SECSPERDAY;
729 break;
730 }
731
732 /*
733 ** "value" is the Epoch-relative time of 00:00:00 UTC on the day in
734 ** question. To get the Epoch-relative time of the specified local
735 ** time on that day, add the transition time and the current offset
736 ** from UTC.
737 */
738 return value + rulep->r_time + offset;
739 }
740
741 /*
742 ** Given a POSIX section 8-style TZ string, fill in the rule tables as
743 ** appropriate.
744 */
745
746 static int
747 tzparse(name, sp, lastditch)
748 const char * name;
749 register struct state * const sp;
750 const int lastditch;
751 {
752 const char * stdname;
753 const char * dstname;
754 size_t stdlen;
755 size_t dstlen;
756 long stdoffset;
757 long dstoffset;
758 register time_t * atp;
759 register unsigned char * typep;
760 register char * cp;
761 register int load_result;
762
763 INITIALIZE(dstname);
764 stdname = name;
765 if (lastditch) {
766 stdlen = strlen(name); /* length of standard zone name */
767 name += stdlen;
768 if (stdlen >= sizeof sp->chars)
769 stdlen = (sizeof sp->chars) - 1;
770 stdoffset = 0;
771 } else {
772 name = getzname(name);
773 stdlen = name - stdname;
774 if (stdlen < 3)
775 return -1;
776 if (*name == '\0')
777 return -1;
778 name = getoffset(name, &stdoffset);
779 if (name == NULL)
780 return -1;
781 }
782 load_result = tzload(TZDEFRULES, sp);
783 if (load_result != 0)
784 sp->leapcnt = 0; /* so, we're off a little */
785 if (*name != '\0') {
786 dstname = name;
787 name = getzname(name);
788 dstlen = name - dstname; /* length of DST zone name */
789 if (dstlen < 3)
790 return -1;
791 if (*name != '\0' && *name != ',' && *name != ';') {
792 name = getoffset(name, &dstoffset);
793 if (name == NULL)
794 return -1;
795 } else dstoffset = stdoffset - SECSPERHOUR;
796 if (*name == '\0' && load_result != 0)
797 name = TZDEFRULESTRING;
798 if (*name == ',' || *name == ';') {
799 struct rule start;
800 struct rule end;
801 register int year;
802 register time_t janfirst;
803 time_t starttime;
804 time_t endtime;
805
806 ++name;
807 if ((name = getrule(name, &start)) == NULL)
808 return -1;
809 if (*name++ != ',')
810 return -1;
811 if ((name = getrule(name, &end)) == NULL)
812 return -1;
813 if (*name != '\0')
814 return -1;
815 sp->typecnt = 2; /* standard time and DST */
816 /*
817 ** Two transitions per year, from EPOCH_YEAR to 2037.
818 */
819 sp->timecnt = 2 * (2037 - EPOCH_YEAR + 1);
820 if (sp->timecnt > TZ_MAX_TIMES)
821 return -1;
822 sp->ttis[0].tt_gmtoff = -dstoffset;
823 sp->ttis[0].tt_isdst = 1;
824 sp->ttis[0].tt_abbrind = stdlen + 1;
825 sp->ttis[1].tt_gmtoff = -stdoffset;
826 sp->ttis[1].tt_isdst = 0;
827 sp->ttis[1].tt_abbrind = 0;
828 atp = sp->ats;
829 typep = sp->types;
830 janfirst = 0;
831 for (year = EPOCH_YEAR; year <= 2037; ++year) {
832 starttime = transtime(janfirst, year, &start,
833 stdoffset);
834 endtime = transtime(janfirst, year, &end,
835 dstoffset);
836 if (starttime > endtime) {
837 *atp++ = endtime;
838 *typep++ = 1; /* DST ends */
839 *atp++ = starttime;
840 *typep++ = 0; /* DST begins */
841 } else {
842 *atp++ = starttime;
843 *typep++ = 0; /* DST begins */
844 *atp++ = endtime;
845 *typep++ = 1; /* DST ends */
846 }
847 janfirst += year_lengths[isleap(year)] *
848 SECSPERDAY;
849 }
850 } else {
851 register long theirstdoffset;
852 register long theiroffset;
853 register int i;
854 register int j;
855
856 if (*name != '\0')
857 return -1;
858 /*
859 ** Initial values of theirstdoffset
860 */
861 theirstdoffset = 0;
862 for (i = 0; i < sp->timecnt; ++i) {
863 j = sp->types[i];
864 if (!sp->ttis[j].tt_isdst) {
865 theirstdoffset =
866 -sp->ttis[j].tt_gmtoff;
867 break;
868 }
869 }
870 /*
871 ** Initially we're assumed to be in standard time.
872 */
873 theiroffset = theirstdoffset;
874 /*
875 ** Now juggle transition times and types
876 ** tracking offsets as you do.
877 */
878 for (i = 0; i < sp->timecnt; ++i) {
879 j = sp->types[i];
880 sp->types[i] = sp->ttis[j].tt_isdst;
881 if (sp->ttis[j].tt_ttisgmt) {
882 /* No adjustment to transition time */
883 } else {
884 /*
885 ** If summer time is in effect, and the
886 ** transition time was not specified as
887 ** standard time, add the summer time
888 ** offset to the transition time;
889 ** otherwise, add the standard time
890 ** offset to the transition time.
891 */
892 /*
893 ** Transitions from DST to DDST
894 ** will effectively disappear since
895 ** POSIX provides for only one DST
896 ** offset.
897 */
898 sp->ats[i] += stdoffset -
899 theirstdoffset;
900 }
901 theiroffset = -sp->ttis[j].tt_gmtoff;
902 if (!sp->ttis[j].tt_isdst)
903 theirstdoffset = theiroffset;
904 }
905 /*
906 ** Finally, fill in ttis.
907 ** ttisstd and ttisgmt need not be handled.
908 */
909 sp->ttis[0].tt_gmtoff = -stdoffset;
910 sp->ttis[0].tt_isdst = FALSE;
911 sp->ttis[0].tt_abbrind = 0;
912 sp->ttis[1].tt_gmtoff = -dstoffset;
913 sp->ttis[1].tt_isdst = TRUE;
914 sp->ttis[1].tt_abbrind = stdlen + 1;
915 sp->typecnt = 2;
916 }
917 } else {
918 dstlen = 0;
919 sp->typecnt = 1; /* only standard time */
920 sp->timecnt = 0;
921 sp->ttis[0].tt_gmtoff = -stdoffset;
922 sp->ttis[0].tt_isdst = 0;
923 sp->ttis[0].tt_abbrind = 0;
924 }
925 sp->charcnt = stdlen + 1;
926 if (dstlen != 0)
927 sp->charcnt += dstlen + 1;
928 if ((size_t) sp->charcnt > sizeof sp->chars)
929 return -1;
930 cp = sp->chars;
931 (void) strncpy(cp, stdname, stdlen);
932 cp += stdlen;
933 *cp++ = '\0';
934 if (dstlen != 0) {
935 (void) strncpy(cp, dstname, dstlen);
936 *(cp + dstlen) = '\0';
937 }
938 return 0;
939 }
940
941 static void
942 gmtload(sp)
943 struct state * const sp;
944 {
945 if (tzload(gmt, sp) != 0)
946 (void) tzparse(gmt, sp, TRUE);
947 }
948
949 static void
950 tzsetwall_unlocked P((void))
951 {
952 if (lcl_is_set < 0)
953 return;
954 lcl_is_set = -1;
955
956 #ifdef ALL_STATE
957 if (lclptr == NULL) {
958 int saveerrno = errno;
959 lclptr = (struct state *) malloc(sizeof *lclptr);
960 errno = saveerrno;
961 if (lclptr == NULL) {
962 settzname(); /* all we can do */
963 return;
964 }
965 }
966 #endif /* defined ALL_STATE */
967 if (tzload((char *) NULL, lclptr) != 0)
968 gmtload(lclptr);
969 settzname();
970 }
971
972 #ifndef STD_INSPIRED
973 /*
974 ** A non-static declaration of tzsetwall in a system header file
975 ** may cause a warning about this upcoming static declaration...
976 */
977 static
978 #endif /* !defined STD_INSPIRED */
979 void
980 tzsetwall P((void))
981 {
982 rwlock_wrlock(&lcl_lock);
983 tzsetwall_unlocked();
984 rwlock_unlock(&lcl_lock);
985 }
986
987 static void
988 tzset_unlocked P((void))
989 {
990 register const char * name;
991 int saveerrno;
992
993 saveerrno = errno;
994 name = getenv("TZ");
995 errno = saveerrno;
996 if (name == NULL) {
997 tzsetwall_unlocked();
998 return;
999 }
1000
1001 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0)
1002 return;
1003 lcl_is_set = strlen(name) < sizeof lcl_TZname;
1004 if (lcl_is_set)
1005 (void)strlcpy(lcl_TZname, name, sizeof(lcl_TZname));
1006
1007 #ifdef ALL_STATE
1008 if (lclptr == NULL) {
1009 saveerrno = errno;
1010 lclptr = (struct state *) malloc(sizeof *lclptr);
1011 errno = saveerrno;
1012 if (lclptr == NULL) {
1013 settzname(); /* all we can do */
1014 return;
1015 }
1016 }
1017 #endif /* defined ALL_STATE */
1018 if (*name == '\0') {
1019 /*
1020 ** User wants it fast rather than right.
1021 */
1022 lclptr->leapcnt = 0; /* so, we're off a little */
1023 lclptr->timecnt = 0;
1024 lclptr->typecnt = 0;
1025 lclptr->ttis[0].tt_isdst = 0;
1026 lclptr->ttis[0].tt_gmtoff = 0;
1027 lclptr->ttis[0].tt_abbrind = 0;
1028 (void)strlcpy(lclptr->chars, gmt, sizeof(lclptr->chars));
1029 } else if (tzload(name, lclptr) != 0)
1030 if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0)
1031 (void) gmtload(lclptr);
1032 settzname();
1033 }
1034
1035 void
1036 tzset P((void))
1037 {
1038 rwlock_wrlock(&lcl_lock);
1039 tzset_unlocked();
1040 rwlock_unlock(&lcl_lock);
1041 }
1042
1043 /*
1044 ** The easy way to behave "as if no library function calls" localtime
1045 ** is to not call it--so we drop its guts into "localsub", which can be
1046 ** freely called. (And no, the PANS doesn't require the above behavior--
1047 ** but it *is* desirable.)
1048 **
1049 ** The unused offset argument is for the benefit of mktime variants.
1050 */
1051
1052 /*ARGSUSED*/
1053 static void
1054 localsub(timep, offset, tmp)
1055 const time_t * const timep;
1056 const long offset;
1057 struct tm * const tmp;
1058 {
1059 register struct state * sp;
1060 register const struct ttinfo * ttisp;
1061 register int i;
1062 const time_t t = *timep;
1063
1064 sp = lclptr;
1065 #ifdef ALL_STATE
1066 if (sp == NULL) {
1067 gmtsub(timep, offset, tmp);
1068 return;
1069 }
1070 #endif /* defined ALL_STATE */
1071 if (sp->timecnt == 0 || t < sp->ats[0]) {
1072 i = 0;
1073 while (sp->ttis[i].tt_isdst)
1074 if (++i >= sp->typecnt) {
1075 i = 0;
1076 break;
1077 }
1078 } else {
1079 for (i = 1; i < sp->timecnt; ++i)
1080 if (t < sp->ats[i])
1081 break;
1082 i = sp->types[i - 1];
1083 }
1084 ttisp = &sp->ttis[i];
1085 /*
1086 ** To get (wrong) behavior that's compatible with System V Release 2.0
1087 ** you'd replace the statement below with
1088 ** t += ttisp->tt_gmtoff;
1089 ** timesub(&t, 0L, sp, tmp);
1090 */
1091 timesub(&t, ttisp->tt_gmtoff, sp, tmp);
1092 tmp->tm_isdst = ttisp->tt_isdst;
1093 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind];
1094 #ifdef TM_ZONE
1095 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind];
1096 #endif /* defined TM_ZONE */
1097 }
1098
1099 struct tm *
1100 localtime(timep)
1101 const time_t * const timep;
1102 {
1103 rwlock_wrlock(&lcl_lock);
1104 tzset_unlocked();
1105 localsub(timep, 0L, &tm);
1106 rwlock_unlock(&lcl_lock);
1107 return &tm;
1108 }
1109
1110 /*
1111 ** Re-entrant version of localtime.
1112 */
1113
1114 struct tm *
1115 localtime_r(timep, tmp)
1116 const time_t * const timep;
1117 struct tm * tmp;
1118 {
1119 rwlock_rdlock(&lcl_lock);
1120 tzset_unlocked();
1121 localsub(timep, 0L, tmp);
1122 rwlock_unlock(&lcl_lock);
1123 return tmp;
1124 }
1125
1126 /*
1127 ** gmtsub is to gmtime as localsub is to localtime.
1128 */
1129
1130 static void
1131 gmtsub(timep, offset, tmp)
1132 const time_t * const timep;
1133 const long offset;
1134 struct tm * const tmp;
1135 {
1136 #ifdef _REENTRANT
1137 static mutex_t gmt_mutex = MUTEX_INITIALIZER;
1138 #endif
1139
1140 mutex_lock(&gmt_mutex);
1141 if (!gmt_is_set) {
1142 #ifdef ALL_STATE
1143 int saveerrno;
1144 #endif
1145 gmt_is_set = TRUE;
1146 #ifdef ALL_STATE
1147 saveerrno = errno;
1148 gmtptr = (struct state *) malloc(sizeof *gmtptr);
1149 errno = saveerrno;
1150 if (gmtptr != NULL)
1151 #endif /* defined ALL_STATE */
1152 gmtload(gmtptr);
1153 }
1154 mutex_unlock(&gmt_mutex);
1155 timesub(timep, offset, gmtptr, tmp);
1156 #ifdef TM_ZONE
1157 /*
1158 ** Could get fancy here and deliver something such as
1159 ** "UTC+xxxx" or "UTC-xxxx" if offset is non-zero,
1160 ** but this is no time for a treasure hunt.
1161 */
1162 if (offset != 0)
1163 tmp->TM_ZONE = (__aconst char *)__UNCONST(wildabbr);
1164 else {
1165 #ifdef ALL_STATE
1166 if (gmtptr == NULL)
1167 tmp->TM_ZONE = (__aconst char *)__UNCONST(gmt);
1168 else tmp->TM_ZONE = gmtptr->chars;
1169 #endif /* defined ALL_STATE */
1170 #ifndef ALL_STATE
1171 tmp->TM_ZONE = gmtptr->chars;
1172 #endif /* State Farm */
1173 }
1174 #endif /* defined TM_ZONE */
1175 }
1176
1177 struct tm *
1178 gmtime(timep)
1179 const time_t * const timep;
1180 {
1181 gmtsub(timep, 0L, &tm);
1182 return &tm;
1183 }
1184
1185 /*
1186 ** Re-entrant version of gmtime.
1187 */
1188
1189 struct tm *
1190 gmtime_r(timep, tmp)
1191 const time_t * const timep;
1192 struct tm * tmp;
1193 {
1194 gmtsub(timep, 0L, tmp);
1195 return tmp;
1196 }
1197
1198 #ifdef STD_INSPIRED
1199
1200 struct tm *
1201 offtime(timep, offset)
1202 const time_t * const timep;
1203 const long offset;
1204 {
1205 gmtsub(timep, offset, &tm);
1206 return &tm;
1207 }
1208
1209 #endif /* defined STD_INSPIRED */
1210
1211 static void
1212 timesub(timep, offset, sp, tmp)
1213 const time_t * const timep;
1214 const long offset;
1215 register const struct state * const sp;
1216 register struct tm * const tmp;
1217 {
1218 register const struct lsinfo * lp;
1219 register long days;
1220 register long rem;
1221 register int y;
1222 register int yleap;
1223 register const int * ip;
1224 register long corr;
1225 register int hit;
1226 register int i;
1227
1228 corr = 0;
1229 hit = 0;
1230 #ifdef ALL_STATE
1231 i = (sp == NULL) ? 0 : sp->leapcnt;
1232 #endif /* defined ALL_STATE */
1233 #ifndef ALL_STATE
1234 i = sp->leapcnt;
1235 #endif /* State Farm */
1236 while (--i >= 0) {
1237 lp = &sp->lsis[i];
1238 if (*timep >= lp->ls_trans) {
1239 if (*timep == lp->ls_trans) {
1240 hit = ((i == 0 && lp->ls_corr > 0) ||
1241 lp->ls_corr > sp->lsis[i - 1].ls_corr);
1242 if (hit)
1243 while (i > 0 &&
1244 sp->lsis[i].ls_trans ==
1245 sp->lsis[i - 1].ls_trans + 1 &&
1246 sp->lsis[i].ls_corr ==
1247 sp->lsis[i - 1].ls_corr + 1) {
1248 ++hit;
1249 --i;
1250 }
1251 }
1252 corr = lp->ls_corr;
1253 break;
1254 }
1255 }
1256 days = *timep / SECSPERDAY;
1257 rem = *timep % SECSPERDAY;
1258 #ifdef mc68k
1259 if (*timep == 0x80000000) {
1260 /*
1261 ** A 3B1 muffs the division on the most negative number.
1262 */
1263 days = -24855;
1264 rem = -11648;
1265 }
1266 #endif /* defined mc68k */
1267 rem += (offset - corr);
1268 while (rem < 0) {
1269 rem += SECSPERDAY;
1270 --days;
1271 }
1272 while (rem >= SECSPERDAY) {
1273 rem -= SECSPERDAY;
1274 ++days;
1275 }
1276 tmp->tm_hour = (int) (rem / SECSPERHOUR);
1277 rem = rem % SECSPERHOUR;
1278 tmp->tm_min = (int) (rem / SECSPERMIN);
1279 /*
1280 ** A positive leap second requires a special
1281 ** representation. This uses "... ??:59:60" et seq.
1282 */
1283 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit;
1284 tmp->tm_wday = (int) ((EPOCH_WDAY + days) % DAYSPERWEEK);
1285 if (tmp->tm_wday < 0)
1286 tmp->tm_wday += DAYSPERWEEK;
1287 y = EPOCH_YEAR;
1288 #define LEAPS_THRU_END_OF(y) ((y) / 4 - (y) / 100 + (y) / 400)
1289 while (days < 0 || days >= (long) year_lengths[yleap = isleap(y)]) {
1290 register int newy;
1291
1292 newy = (int)(y + days / DAYSPERNYEAR);
1293 if (days < 0)
1294 --newy;
1295 days -= (newy - y) * DAYSPERNYEAR +
1296 LEAPS_THRU_END_OF(newy - 1) -
1297 LEAPS_THRU_END_OF(y - 1);
1298 y = newy;
1299 }
1300 tmp->tm_year = y - TM_YEAR_BASE;
1301 tmp->tm_yday = (int) days;
1302 ip = mon_lengths[yleap];
1303 for (tmp->tm_mon = 0; days >= (long) ip[tmp->tm_mon]; ++(tmp->tm_mon))
1304 days = days - (long) ip[tmp->tm_mon];
1305 tmp->tm_mday = (int) (days + 1);
1306 tmp->tm_isdst = 0;
1307 #ifdef TM_GMTOFF
1308 tmp->TM_GMTOFF = offset;
1309 #endif /* defined TM_GMTOFF */
1310 }
1311
1312 char *
1313 ctime(timep)
1314 const time_t * const timep;
1315 {
1316 /*
1317 ** Section 4.12.3.2 of X3.159-1989 requires that
1318 ** The ctime function converts the calendar time pointed to by timer
1319 ** to local time in the form of a string. It is equivalent to
1320 ** asctime(localtime(timer))
1321 */
1322 return asctime(localtime(timep));
1323 }
1324
1325 char *
1326 ctime_r(timep, buf)
1327 const time_t * const timep;
1328 char * buf;
1329 {
1330 struct tm tmp;
1331
1332 return asctime_r(localtime_r(timep, &tmp), buf);
1333 }
1334
1335 /*
1336 ** Adapted from code provided by Robert Elz, who writes:
1337 ** The "best" way to do mktime I think is based on an idea of Bob
1338 ** Kridle's (so its said...) from a long time ago.
1339 ** [kridle (at) xinet.com as of 1996-01-16.]
1340 ** It does a binary search of the time_t space. Since time_t's are
1341 ** just 32 bits, its a max of 32 iterations (even at 64 bits it
1342 ** would still be very reasonable).
1343 */
1344
1345 #ifndef WRONG
1346 #define WRONG (-1)
1347 #endif /* !defined WRONG */
1348
1349 /*
1350 ** Simplified normalize logic courtesy Paul Eggert (eggert (at) twinsun.com).
1351 */
1352
1353 static int
1354 increment_overflow(number, delta)
1355 int * number;
1356 int delta;
1357 {
1358 int number0;
1359
1360 number0 = *number;
1361 *number += delta;
1362 return (*number < number0) != (delta < 0);
1363 }
1364
1365 static int
1366 normalize_overflow(tensptr, unitsptr, base)
1367 int * const tensptr;
1368 int * const unitsptr;
1369 const int base;
1370 {
1371 register int tensdelta;
1372
1373 tensdelta = (*unitsptr >= 0) ?
1374 (*unitsptr / base) :
1375 (-1 - (-1 - *unitsptr) / base);
1376 *unitsptr -= tensdelta * base;
1377 return increment_overflow(tensptr, tensdelta);
1378 }
1379
1380 static int
1381 tmcomp(atmp, btmp)
1382 register const struct tm * const atmp;
1383 register const struct tm * const btmp;
1384 {
1385 register int result;
1386
1387 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 &&
1388 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 &&
1389 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 &&
1390 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 &&
1391 (result = (atmp->tm_min - btmp->tm_min)) == 0)
1392 result = atmp->tm_sec - btmp->tm_sec;
1393 return result;
1394 }
1395
1396 static time_t
1397 time2sub(tmp, funcp, offset, okayp, do_norm_secs)
1398 struct tm * const tmp;
1399 void (* const funcp) P((const time_t*, long, struct tm*));
1400 const long offset;
1401 int * const okayp;
1402 const int do_norm_secs;
1403 {
1404 register const struct state * sp;
1405 register int dir;
1406 register int bits;
1407 register int i, j ;
1408 register int saved_seconds;
1409 time_t newt;
1410 time_t t;
1411 struct tm yourtm, mytm;
1412
1413 *okayp = FALSE;
1414 yourtm = *tmp;
1415 if (do_norm_secs) {
1416 if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec,
1417 SECSPERMIN))
1418 return WRONG;
1419 }
1420 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR))
1421 return WRONG;
1422 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY))
1423 return WRONG;
1424 if (normalize_overflow(&yourtm.tm_year, &yourtm.tm_mon, MONSPERYEAR))
1425 return WRONG;
1426 /*
1427 ** Turn yourtm.tm_year into an actual year number for now.
1428 ** It is converted back to an offset from TM_YEAR_BASE later.
1429 */
1430 if (increment_overflow(&yourtm.tm_year, TM_YEAR_BASE))
1431 return WRONG;
1432 while (yourtm.tm_mday <= 0) {
1433 if (increment_overflow(&yourtm.tm_year, -1))
1434 return WRONG;
1435 i = yourtm.tm_year + (1 < yourtm.tm_mon);
1436 yourtm.tm_mday += year_lengths[isleap(i)];
1437 }
1438 while (yourtm.tm_mday > DAYSPERLYEAR) {
1439 i = yourtm.tm_year + (1 < yourtm.tm_mon);
1440 yourtm.tm_mday -= year_lengths[isleap(i)];
1441 if (increment_overflow(&yourtm.tm_year, 1))
1442 return WRONG;
1443 }
1444 for ( ; ; ) {
1445 i = mon_lengths[isleap(yourtm.tm_year)][yourtm.tm_mon];
1446 if (yourtm.tm_mday <= i)
1447 break;
1448 yourtm.tm_mday -= i;
1449 if (++yourtm.tm_mon >= MONSPERYEAR) {
1450 yourtm.tm_mon = 0;
1451 if (increment_overflow(&yourtm.tm_year, 1))
1452 return WRONG;
1453 }
1454 }
1455 if (increment_overflow(&yourtm.tm_year, -TM_YEAR_BASE))
1456 return WRONG;
1457 if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN)
1458 saved_seconds = 0;
1459 else if (yourtm.tm_year + TM_YEAR_BASE < EPOCH_YEAR) {
1460 /*
1461 ** We can't set tm_sec to 0, because that might push the
1462 ** time below the minimum representable time.
1463 ** Set tm_sec to 59 instead.
1464 ** This assumes that the minimum representable time is
1465 ** not in the same minute that a leap second was deleted from,
1466 ** which is a safer assumption than using 58 would be.
1467 */
1468 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN))
1469 return WRONG;
1470 saved_seconds = yourtm.tm_sec;
1471 yourtm.tm_sec = SECSPERMIN - 1;
1472 } else {
1473 saved_seconds = yourtm.tm_sec;
1474 yourtm.tm_sec = 0;
1475 }
1476 /*
1477 ** Divide the search space in half
1478 ** (this works whether time_t is signed or unsigned).
1479 */
1480 bits = TYPE_BIT(time_t) - 1;
1481 /*
1482 ** If time_t is signed, then 0 is just above the median,
1483 ** assuming two's complement arithmetic.
1484 ** If time_t is unsigned, then (1 << bits) is just above the median.
1485 */
1486 /*CONSTCOND*/
1487 t = TYPE_SIGNED(time_t) ? 0 : (((time_t) 1) << bits);
1488 for ( ; ; ) {
1489 (*funcp)(&t, offset, &mytm);
1490 dir = tmcomp(&mytm, &yourtm);
1491 if (dir != 0) {
1492 if (bits-- < 0)
1493 return WRONG;
1494 if (bits < 0)
1495 --t; /* may be needed if new t is minimal */
1496 else if (dir > 0)
1497 t -= ((time_t) 1) << bits;
1498 else t += ((time_t) 1) << bits;
1499 continue;
1500 }
1501 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst)
1502 break;
1503 /*
1504 ** Right time, wrong type.
1505 ** Hunt for right time, right type.
1506 ** It's okay to guess wrong since the guess
1507 ** gets checked.
1508 */
1509 /*
1510 ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's.
1511 */
1512 sp = (const struct state *)
1513 (((void *) funcp == (void *) localsub) ?
1514 lclptr : gmtptr);
1515 #ifdef ALL_STATE
1516 if (sp == NULL)
1517 return WRONG;
1518 #endif /* defined ALL_STATE */
1519 for (i = sp->typecnt - 1; i >= 0; --i) {
1520 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst)
1521 continue;
1522 for (j = sp->typecnt - 1; j >= 0; --j) {
1523 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst)
1524 continue;
1525 newt = t + sp->ttis[j].tt_gmtoff -
1526 sp->ttis[i].tt_gmtoff;
1527 (*funcp)(&newt, offset, &mytm);
1528 if (tmcomp(&mytm, &yourtm) != 0)
1529 continue;
1530 if (mytm.tm_isdst != yourtm.tm_isdst)
1531 continue;
1532 /*
1533 ** We have a match.
1534 */
1535 t = newt;
1536 goto label;
1537 }
1538 }
1539 return WRONG;
1540 }
1541 label:
1542 newt = t + saved_seconds;
1543 if ((newt < t) != (saved_seconds < 0))
1544 return WRONG;
1545 t = newt;
1546 (*funcp)(&t, offset, tmp);
1547 *okayp = TRUE;
1548 return t;
1549 }
1550
1551 static time_t
1552 time2(tmp, funcp, offset, okayp)
1553 struct tm * const tmp;
1554 void (* const funcp) P((const time_t*, long, struct tm*));
1555 const long offset;
1556 int * const okayp;
1557 {
1558 time_t t;
1559
1560 /*
1561 ** First try without normalization of seconds
1562 ** (in case tm_sec contains a value associated with a leap second).
1563 ** If that fails, try with normalization of seconds.
1564 */
1565 t = time2sub(tmp, funcp, offset, okayp, FALSE);
1566 return *okayp ? t : time2sub(tmp, funcp, offset, okayp, TRUE);
1567 }
1568
1569 static time_t
1570 time1(tmp, funcp, offset)
1571 struct tm * const tmp;
1572 void (* const funcp) P((const time_t *, long, struct tm *));
1573 const long offset;
1574 {
1575 register time_t t;
1576 register const struct state * sp;
1577 register int samei, otheri;
1578 register int sameind, otherind;
1579 register int i;
1580 register int nseen;
1581 int seen[TZ_MAX_TYPES];
1582 int types[TZ_MAX_TYPES];
1583 int okay;
1584
1585 if (tmp->tm_isdst > 1)
1586 tmp->tm_isdst = 1;
1587 t = time2(tmp, funcp, offset, &okay);
1588 #ifdef PCTS
1589 /*
1590 ** PCTS code courtesy Grant Sullivan (grant (at) osf.org).
1591 */
1592 if (okay)
1593 return t;
1594 if (tmp->tm_isdst < 0)
1595 tmp->tm_isdst = 0; /* reset to std and try again */
1596 #endif /* defined PCTS */
1597 #ifndef PCTS
1598 if (okay || tmp->tm_isdst < 0)
1599 return t;
1600 #endif /* !defined PCTS */
1601 /*
1602 ** We're supposed to assume that somebody took a time of one type
1603 ** and did some math on it that yielded a "struct tm" that's bad.
1604 ** We try to divine the type they started from and adjust to the
1605 ** type they need.
1606 */
1607 /*
1608 ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's.
1609 */
1610 sp = (const struct state *) (((void *) funcp == (void *) localsub) ?
1611 lclptr : gmtptr);
1612 #ifdef ALL_STATE
1613 if (sp == NULL)
1614 return WRONG;
1615 #endif /* defined ALL_STATE */
1616 for (i = 0; i < sp->typecnt; ++i)
1617 seen[i] = FALSE;
1618 nseen = 0;
1619 for (i = sp->timecnt - 1; i >= 0; --i)
1620 if (!seen[sp->types[i]]) {
1621 seen[sp->types[i]] = TRUE;
1622 types[nseen++] = sp->types[i];
1623 }
1624 for (sameind = 0; sameind < nseen; ++sameind) {
1625 samei = types[sameind];
1626 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst)
1627 continue;
1628 for (otherind = 0; otherind < nseen; ++otherind) {
1629 otheri = types[otherind];
1630 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst)
1631 continue;
1632 tmp->tm_sec += (int)(sp->ttis[otheri].tt_gmtoff -
1633 sp->ttis[samei].tt_gmtoff);
1634 tmp->tm_isdst = !tmp->tm_isdst;
1635 t = time2(tmp, funcp, offset, &okay);
1636 if (okay)
1637 return t;
1638 tmp->tm_sec -= (int)(sp->ttis[otheri].tt_gmtoff -
1639 sp->ttis[samei].tt_gmtoff);
1640 tmp->tm_isdst = !tmp->tm_isdst;
1641 }
1642 }
1643 return WRONG;
1644 }
1645
1646 time_t
1647 mktime(tmp)
1648 struct tm * const tmp;
1649 {
1650 time_t result;
1651
1652 rwlock_wrlock(&lcl_lock);
1653 tzset_unlocked();
1654 result = time1(tmp, localsub, 0L);
1655 rwlock_unlock(&lcl_lock);
1656 return (result);
1657 }
1658
1659 #ifdef STD_INSPIRED
1660
1661 time_t
1662 timelocal(tmp)
1663 struct tm * const tmp;
1664 {
1665 tmp->tm_isdst = -1; /* in case it wasn't initialized */
1666 return mktime(tmp);
1667 }
1668
1669 time_t
1670 timegm(tmp)
1671 struct tm * const tmp;
1672 {
1673 tmp->tm_isdst = 0;
1674 return time1(tmp, gmtsub, 0L);
1675 }
1676
1677 time_t
1678 timeoff(tmp, offset)
1679 struct tm * const tmp;
1680 const long offset;
1681 {
1682 tmp->tm_isdst = 0;
1683 return time1(tmp, gmtsub, offset);
1684 }
1685
1686 #endif /* defined STD_INSPIRED */
1687
1688 #ifdef CMUCS
1689
1690 /*
1691 ** The following is supplied for compatibility with
1692 ** previous versions of the CMUCS runtime library.
1693 */
1694
1695 long
1696 gtime(tmp)
1697 struct tm * const tmp;
1698 {
1699 const time_t t = mktime(tmp);
1700
1701 if (t == WRONG)
1702 return -1;
1703 return t;
1704 }
1705
1706 #endif /* defined CMUCS */
1707
1708 /*
1709 ** XXX--is the below the right way to conditionalize??
1710 */
1711
1712 #ifdef STD_INSPIRED
1713
1714 /*
1715 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599
1716 ** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which
1717 ** is not the case if we are accounting for leap seconds.
1718 ** So, we provide the following conversion routines for use
1719 ** when exchanging timestamps with POSIX conforming systems.
1720 */
1721
1722 static long
1723 leapcorr(timep)
1724 time_t * timep;
1725 {
1726 register struct state * sp;
1727 register struct lsinfo * lp;
1728 register int i;
1729
1730 sp = lclptr;
1731 i = sp->leapcnt;
1732 while (--i >= 0) {
1733 lp = &sp->lsis[i];
1734 if (*timep >= lp->ls_trans)
1735 return lp->ls_corr;
1736 }
1737 return 0;
1738 }
1739
1740 time_t
1741 time2posix(t)
1742 time_t t;
1743 {
1744 time_t result;
1745
1746 rwlock_wrlock(&lcl_lock);
1747 tzset_unlocked();
1748 result = t - leapcorr(&t);
1749 rwlock_unlock(&lcl_lock);
1750 return (result);
1751 }
1752
1753 time_t
1754 posix2time(t)
1755 time_t t;
1756 {
1757 time_t x;
1758 time_t y;
1759
1760 rwlock_wrlock(&lcl_lock);
1761 tzset_unlocked();
1762 /*
1763 ** For a positive leap second hit, the result
1764 ** is not unique. For a negative leap second
1765 ** hit, the corresponding time doesn't exist,
1766 ** so we return an adjacent second.
1767 */
1768 x = t + leapcorr(&t);
1769 y = x - leapcorr(&x);
1770 if (y < t) {
1771 do {
1772 x++;
1773 y = x - leapcorr(&x);
1774 } while (y < t);
1775 if (t != y) {
1776 rwlock_unlock(&lcl_lock);
1777 return x - 1;
1778 }
1779 } else if (y > t) {
1780 do {
1781 --x;
1782 y = x - leapcorr(&x);
1783 } while (y > t);
1784 if (t != y) {
1785 rwlock_unlock(&lcl_lock);
1786 return x + 1;
1787 }
1788 }
1789 rwlock_unlock(&lcl_lock);
1790 return x;
1791 }
1792
1793 #endif /* defined STD_INSPIRED */
1794