]> git.saurik.com Git - apple/libc.git/blob - stdtime/FreeBSD/localtime.c
projects / apple / libc.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Libc-594.1.4.tar.gz
[apple/libc.git] / stdtime / FreeBSD / localtime.c
1 /*
2 ** This file is in the public domain, so clarified as of
3 ** 1996-06-05 by Arthur David Olson (arthur_david_olson@nih.gov).
4 */
5
6 #include <sys/cdefs.h>
7 #ifndef lint
8 #ifndef NOID
9 static char elsieid[] __unused = "@(#)localtime.c 7.78";
10 #endif /* !defined NOID */
11 #endif /* !defined lint */
12 __FBSDID("$FreeBSD: src/lib/libc/stdtime/localtime.c,v 1.40 2004/08/24 00:15:37 peter Exp $");
13
14 /*
15 ** Leap second handling from Bradley White (bww@k.gp.cs.cmu.edu).
16 ** POSIX-style TZ environment variable handling from Guy Harris
17 ** (guy@auspex.com).
18 */
19
20 /*LINTLIBRARY*/
21
22 #include "namespace.h"
23 #include <sys/types.h>
24 #include <sys/stat.h>
25 #include <fcntl.h>
26 #include <pthread.h>
27 #include "private.h"
28 #include "un-namespace.h"
29
30 #include "tzfile.h"
31
32 #include "libc_private.h"
33
34 #define _MUTEX_LOCK(x) if (__isthreaded) _pthread_mutex_lock(x)
35 #define _MUTEX_UNLOCK(x) if (__isthreaded) _pthread_mutex_unlock(x)
36
37 /*
38 ** SunOS 4.1.1 headers lack O_BINARY.
39 */
40
41 #ifdef O_BINARY
42 #define OPEN_MODE (O_RDONLY | O_BINARY)
43 #endif /* defined O_BINARY */
44 #ifndef O_BINARY
45 #define OPEN_MODE O_RDONLY
46 #endif /* !defined O_BINARY */
47
48 #ifndef WILDABBR
49 /*
50 ** Someone might make incorrect use of a time zone abbreviation:
51 ** 1. They might reference tzname[0] before calling tzset (explicitly
52 ** or implicitly).
53 ** 2. They might reference tzname[1] before calling tzset (explicitly
54 ** or implicitly).
55 ** 3. They might reference tzname[1] after setting to a time zone
56 ** in which Daylight Saving Time is never observed.
57 ** 4. They might reference tzname[0] after setting to a time zone
58 ** in which Standard Time is never observed.
59 ** 5. They might reference tm.TM_ZONE after calling offtime.
60 ** What's best to do in the above cases is open to debate;
61 ** for now, we just set things up so that in any of the five cases
62 ** WILDABBR is used. Another possibility: initialize tzname[0] to the
63 ** string "tzname[0] used before set", and similarly for the other cases.
64 ** And another: initialize tzname[0] to "ERA", with an explanation in the
65 ** manual page of what this "time zone abbreviation" means (doing this so
66 ** that tzname[0] has the "normal" length of three characters).
67 */
68 #define WILDABBR " "
69 #endif /* !defined WILDABBR */
70
71 static char wildabbr[] = "WILDABBR";
72
73 /*
74 * In June 2004 it was decided UTC was a more appropriate default time
75 * zone than GMT.
76 */
77
78 static const char gmt[] = "UTC";
79
80 /*
81 ** The DST rules to use if TZ has no rules and we can't load TZDEFRULES.
82 ** We default to US rules as of 1999-08-17.
83 ** POSIX 1003.1 section 8.1.1 says that the default DST rules are
84 ** implementation dependent; for historical reasons, US rules are a
85 ** common default.
86 */
87 #ifndef TZDEFRULESTRING
88 #define TZDEFRULESTRING ",M4.1.0,M10.5.0"
89 #endif /* !defined TZDEFDST */
90
91 struct ttinfo { /* time type information */
92 long tt_gmtoff; /* UTC offset in seconds */
93 int tt_isdst; /* used to set tm_isdst */
94 int tt_abbrind; /* abbreviation list index */
95 int tt_ttisstd; /* TRUE if transition is std time */
96 int tt_ttisgmt; /* TRUE if transition is UTC */
97 };
98
99 struct lsinfo { /* leap second information */
100 time_t ls_trans; /* transition time */
101 long ls_corr; /* correction to apply */
102 };
103
104 #define BIGGEST(a, b) (((a) > (b)) ? (a) : (b))
105
106 #ifdef TZNAME_MAX
107 #define MY_TZNAME_MAX TZNAME_MAX
108 #endif /* defined TZNAME_MAX */
109 #ifndef TZNAME_MAX
110 #define MY_TZNAME_MAX 255
111 #endif /* !defined TZNAME_MAX */
112
113 struct state {
114 int leapcnt;
115 int timecnt;
116 int typecnt;
117 int charcnt;
118 time_t ats[TZ_MAX_TIMES];
119 unsigned char types[TZ_MAX_TIMES];
120 struct ttinfo ttis[TZ_MAX_TYPES];
121 char chars[BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt),
122 (2 * (MY_TZNAME_MAX + 1)))];
123 struct lsinfo lsis[TZ_MAX_LEAPS];
124 };
125
126 struct rule {
127 int r_type; /* type of rule--see below */
128 int r_day; /* day number of rule */
129 int r_week; /* week number of rule */
130 int r_mon; /* month number of rule */
131 long r_time; /* transition time of rule */
132 };
133
134 #define JULIAN_DAY 0 /* Jn - Julian day */
135 #define DAY_OF_YEAR 1 /* n - day of year */
136 #define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */
137
138 /*
139 ** Prototypes for static functions.
140 */
141
142 static long detzcode(const char * codep);
143 static const char * getzname(const char * strp);
144 static const char * getnum(const char * strp, int * nump, int min,
145 int max);
146 static const char * getsecs(const char * strp, long * secsp);
147 static const char * getoffset(const char * strp, long * offsetp);
148 static const char * getrule(const char * strp, struct rule * rulep);
149 static void gmtload(struct state * sp);
150 static void gmtsub(const time_t * timep, long offset,
151 struct tm * tmp);
152 static void localsub(const time_t * timep, long offset,
153 struct tm * tmp);
154 static int increment_overflow(int * number, int delta);
155 static int normalize_overflow(int * tensptr, int * unitsptr,
156 int base);
157 static void settzname(void);
158 static time_t time1(struct tm * tmp,
159 void(*funcp) (const time_t *,
160 long, struct tm *),
161 long offset);
162 static time_t time2(struct tm *tmp,
163 void(*funcp) (const time_t *,
164 long, struct tm*),
165 long offset, int * okayp);
166 static time_t time2sub(struct tm *tmp,
167 void(*funcp) (const time_t *,
168 long, struct tm*),
169 long offset, int * okayp, int do_norm_secs);
170 static void timesub(const time_t * timep, long offset,
171 const struct state * sp, struct tm * tmp);
172 static int tmcomp(const struct tm * atmp,
173 const struct tm * btmp);
174 static time_t transtime(time_t janfirst, int year,
175 const struct rule * rulep, long offset);
176 static int tzload(const char * name, struct state * sp);
177 static int tzparse(const char * name, struct state * sp,
178 int lastditch);
179
180 #ifdef ALL_STATE
181 static struct state * lclptr;
182 static struct state * gmtptr;
183 #endif /* defined ALL_STATE */
184
185 #ifndef ALL_STATE
186 static struct state lclmem;
187 static struct state gmtmem;
188 #define lclptr (&lclmem)
189 #define gmtptr (&gmtmem)
190 #endif /* State Farm */
191
192 #ifndef TZ_STRLEN_MAX
193 #define TZ_STRLEN_MAX 255
194 #endif /* !defined TZ_STRLEN_MAX */
195
196 static char lcl_TZname[TZ_STRLEN_MAX + 1];
197 static int lcl_is_set;
198 static int gmt_is_set;
199 static pthread_mutex_t lcl_mutex = PTHREAD_MUTEX_INITIALIZER;
200 static pthread_mutex_t gmt_mutex = PTHREAD_MUTEX_INITIALIZER;
201
202 char * tzname[2] = {
203 wildabbr,
204 wildabbr
205 };
206
207 /*
208 ** Section 4.12.3 of X3.159-1989 requires that
209 ** Except for the strftime function, these functions [asctime,
210 ** ctime, gmtime, localtime] return values in one of two static
211 ** objects: a broken-down time structure and an array of char.
212 ** Thanks to Paul Eggert (eggert@twinsun.com) for noting this.
213 */
214
215 static struct tm tm;
216
217 #ifdef USG_COMPAT
218 time_t timezone = 0;
219 int daylight = 0;
220 #endif /* defined USG_COMPAT */
221
222 #ifdef ALTZONE
223 time_t altzone = 0;
224 #endif /* defined ALTZONE */
225
226 static long
227 detzcode(codep)
228 const char * const codep;
229 {
230 long result;
231 int i;
232
233 result = (codep[0] & 0x80) ? ~0L : 0L;
234 for (i = 0; i < 4; ++i)
235 result = (result << 8) | (codep[i] & 0xff);
236 return result;
237 }
238
239 static void
240 settzname(void)
241 {
242 struct state * sp = lclptr;
243 int i;
244
245 tzname[0] = wildabbr;
246 tzname[1] = wildabbr;
247 #ifdef USG_COMPAT
248 daylight = 0;
249 timezone = 0;
250 #endif /* defined USG_COMPAT */
251 #ifdef ALTZONE
252 altzone = 0;
253 #endif /* defined ALTZONE */
254 #ifdef ALL_STATE
255 if (sp == NULL) {
256 tzname[0] = tzname[1] = gmt;
257 return;
258 }
259 #endif /* defined ALL_STATE */
260 for (i = 0; i < sp->typecnt; ++i) {
261 const struct ttinfo * const ttisp = &sp->ttis[i];
262
263 tzname[ttisp->tt_isdst] =
264 &sp->chars[ttisp->tt_abbrind];
265 #ifdef USG_COMPAT
266 if (ttisp->tt_isdst)
267 daylight = 1;
268 if (i == 0 || !ttisp->tt_isdst)
269 timezone = -(ttisp->tt_gmtoff);
270 #endif /* defined USG_COMPAT */
271 #ifdef ALTZONE
272 if (i == 0 || ttisp->tt_isdst)
273 altzone = -(ttisp->tt_gmtoff);
274 #endif /* defined ALTZONE */
275 }
276 /*
277 ** And to get the latest zone names into tzname. . .
278 */
279 for (i = 0; i < sp->timecnt; ++i) {
280 const struct ttinfo * const ttisp =
281 &sp->ttis[
282 sp->types[i]];
283
284 tzname[ttisp->tt_isdst] =
285 &sp->chars[ttisp->tt_abbrind];
286 }
287 }
288
289 static int
290 tzload(name, sp)
291 const char * name;
292 struct state * const sp;
293 {
294 const char * p;
295 int i;
296 int fid;
297
298 /* XXX The following is from OpenBSD, and I'm not sure it is correct */
299 if (name != NULL && issetugid() != 0)
300 if ((name[0] == ':' && name[1] == '/') ||
301 name[0] == '/' || strchr(name, '.'))
302 name = NULL;
303 if (name == NULL && (name = TZDEFAULT) == NULL)
304 return -1;
305 {
306 int doaccess;
307 struct stat stab;
308 /*
309 ** Section 4.9.1 of the C standard says that
310 ** "FILENAME_MAX expands to an integral constant expression
311 ** that is the size needed for an array of char large enough
312 ** to hold the longest file name string that the implementation
313 ** guarantees can be opened."
314 */
315 char fullname[FILENAME_MAX + 1];
316
317 if (name[0] == ':')
318 ++name;
319 doaccess = name[0] == '/';
320 if (!doaccess) {
321 if ((p = TZDIR) == NULL)
322 return -1;
323 if ((strlen(p) + 1 + strlen(name) + 1) >= sizeof fullname)
324 return -1;
325 (void) strcpy(fullname, p);
326 (void) strcat(fullname, "/");
327 (void) strcat(fullname, name);
328 /*
329 ** Set doaccess if '.' (as in "../") shows up in name.
330 */
331 if (strchr(name, '.') != NULL)
332 doaccess = TRUE;
333 name = fullname;
334 }
335 if (doaccess && access(name, R_OK) != 0)
336 return -1;
337 if ((fid = _open(name, OPEN_MODE)) == -1)
338 return -1;
339 if ((_fstat(fid, &stab) < 0) || !S_ISREG(stab.st_mode)) {
340 _close(fid);
341 return -1;
342 }
343 }
344 {
345 struct tzhead * tzhp;
346 union {
347 struct tzhead tzhead;
348 char buf[sizeof *sp + sizeof *tzhp];
349 } u;
350 int ttisstdcnt;
351 int ttisgmtcnt;
352
353 i = _read(fid, u.buf, sizeof u.buf);
354 if (_close(fid) != 0)
355 return -1;
356 ttisstdcnt = (int) detzcode(u.tzhead.tzh_ttisstdcnt);
357 ttisgmtcnt = (int) detzcode(u.tzhead.tzh_ttisgmtcnt);
358 sp->leapcnt = (int) detzcode(u.tzhead.tzh_leapcnt);
359 sp->timecnt = (int) detzcode(u.tzhead.tzh_timecnt);
360 sp->typecnt = (int) detzcode(u.tzhead.tzh_typecnt);
361 sp->charcnt = (int) detzcode(u.tzhead.tzh_charcnt);
362 p = u.tzhead.tzh_charcnt + sizeof u.tzhead.tzh_charcnt;
363 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS ||
364 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES ||
365 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES ||
366 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS ||
367 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) ||
368 (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0))
369 return -1;
370 if (i - (p - u.buf) < sp->timecnt * 4 + /* ats */
371 sp->timecnt + /* types */
372 sp->typecnt * (4 + 2) + /* ttinfos */
373 sp->charcnt + /* chars */
374 sp->leapcnt * (4 + 4) + /* lsinfos */
375 ttisstdcnt + /* ttisstds */
376 ttisgmtcnt) /* ttisgmts */
377 return -1;
378 for (i = 0; i < sp->timecnt; ++i) {
379 sp->ats[i] = detzcode(p);
380 p += 4;
381 }
382 for (i = 0; i < sp->timecnt; ++i) {
383 sp->types[i] = (unsigned char) *p++;
384 if (sp->types[i] >= sp->typecnt)
385 return -1;
386 }
387 for (i = 0; i < sp->typecnt; ++i) {
388 struct ttinfo * ttisp;
389
390 ttisp = &sp->ttis[i];
391 ttisp->tt_gmtoff = detzcode(p);
392 p += 4;
393 ttisp->tt_isdst = (unsigned char) *p++;
394 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1)
395 return -1;
396 ttisp->tt_abbrind = (unsigned char) *p++;
397 if (ttisp->tt_abbrind < 0 ||
398 ttisp->tt_abbrind > sp->charcnt)
399 return -1;
400 }
401 for (i = 0; i < sp->charcnt; ++i)
402 sp->chars[i] = *p++;
403 sp->chars[i] = '\0'; /* ensure '\0' at end */
404 for (i = 0; i < sp->leapcnt; ++i) {
405 struct lsinfo * lsisp;
406
407 lsisp = &sp->lsis[i];
408 lsisp->ls_trans = detzcode(p);
409 p += 4;
410 lsisp->ls_corr = detzcode(p);
411 p += 4;
412 }
413 for (i = 0; i < sp->typecnt; ++i) {
414 struct ttinfo * ttisp;
415
416 ttisp = &sp->ttis[i];
417 if (ttisstdcnt == 0)
418 ttisp->tt_ttisstd = FALSE;
419 else {
420 ttisp->tt_ttisstd = *p++;
421 if (ttisp->tt_ttisstd != TRUE &&
422 ttisp->tt_ttisstd != FALSE)
423 return -1;
424 }
425 }
426 for (i = 0; i < sp->typecnt; ++i) {
427 struct ttinfo * ttisp;
428
429 ttisp = &sp->ttis[i];
430 if (ttisgmtcnt == 0)
431 ttisp->tt_ttisgmt = FALSE;
432 else {
433 ttisp->tt_ttisgmt = *p++;
434 if (ttisp->tt_ttisgmt != TRUE &&
435 ttisp->tt_ttisgmt != FALSE)
436 return -1;
437 }
438 }
439 }
440 return 0;
441 }
442
443 static const int mon_lengths[2][MONSPERYEAR] = {
444 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
445 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }
446 };
447
448 static const int year_lengths[2] = {
449 DAYSPERNYEAR, DAYSPERLYEAR
450 };
451
452 /*
453 ** Given a pointer into a time zone string, scan until a character that is not
454 ** a valid character in a zone name is found. Return a pointer to that
455 ** character.
456 */
457
458 static const char *
459 getzname(strp)
460 const char * strp;
461 {
462 char c;
463
464 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' &&
465 c != '+')
466 ++strp;
467 return strp;
468 }
469
470 /*
471 ** Given a pointer into a time zone string, extract a number from that string.
472 ** Check that the number is within a specified range; if it is not, return
473 ** NULL.
474 ** Otherwise, return a pointer to the first character not part of the number.
475 */
476
477 static const char *
478 getnum(strp, nump, min, max)
479 const char * strp;
480 int * const nump;
481 const int min;
482 const int max;
483 {
484 char c;
485 int num;
486
487 if (strp == NULL || !is_digit(c = *strp))
488 return NULL;
489 num = 0;
490 do {
491 num = num * 10 + (c - '0');
492 if (num > max)
493 return NULL; /* illegal value */
494 c = *++strp;
495 } while (is_digit(c));
496 if (num < min)
497 return NULL; /* illegal value */
498 *nump = num;
499 return strp;
500 }
501
502 /*
503 ** Given a pointer into a time zone string, extract a number of seconds,
504 ** in hh[:mm[:ss]] form, from the string.
505 ** If any error occurs, return NULL.
506 ** Otherwise, return a pointer to the first character not part of the number
507 ** of seconds.
508 */
509
510 static const char *
511 getsecs(strp, secsp)
512 const char * strp;
513 long * const secsp;
514 {
515 int num;
516
517 /*
518 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like
519 ** "M10.4.6/26", which does not conform to Posix,
520 ** but which specifies the equivalent of
521 ** ``02:00 on the first Sunday on or after 23 Oct''.
522 */
523 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1);
524 if (strp == NULL)
525 return NULL;
526 *secsp = num * (long) SECSPERHOUR;
527 if (*strp == ':') {
528 ++strp;
529 strp = getnum(strp, &num, 0, MINSPERHOUR - 1);
530 if (strp == NULL)
531 return NULL;
532 *secsp += num * SECSPERMIN;
533 if (*strp == ':') {
534 ++strp;
535 /* `SECSPERMIN' allows for leap seconds. */
536 strp = getnum(strp, &num, 0, SECSPERMIN);
537 if (strp == NULL)
538 return NULL;
539 *secsp += num;
540 }
541 }
542 return strp;
543 }
544
545 /*
546 ** Given a pointer into a time zone string, extract an offset, in
547 ** [+-]hh[:mm[:ss]] form, from the string.
548 ** If any error occurs, return NULL.
549 ** Otherwise, return a pointer to the first character not part of the time.
550 */
551
552 static const char *
553 getoffset(strp, offsetp)
554 const char * strp;
555 long * const offsetp;
556 {
557 int neg = 0;
558
559 if (*strp == '-') {
560 neg = 1;
561 ++strp;
562 } else if (*strp == '+')
563 ++strp;
564 strp = getsecs(strp, offsetp);
565 if (strp == NULL)
566 return NULL; /* illegal time */
567 if (neg)
568 *offsetp = -*offsetp;
569 return strp;
570 }
571
572 /*
573 ** Given a pointer into a time zone string, extract a rule in the form
574 ** date[/time]. See POSIX section 8 for the format of "date" and "time".
575 ** If a valid rule is not found, return NULL.
576 ** Otherwise, return a pointer to the first character not part of the rule.
577 */
578
579 static const char *
580 getrule(strp, rulep)
581 const char * strp;
582 struct rule * const rulep;
583 {
584 if (*strp == 'J') {
585 /*
586 ** Julian day.
587 */
588 rulep->r_type = JULIAN_DAY;
589 ++strp;
590 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR);
591 } else if (*strp == 'M') {
592 /*
593 ** Month, week, day.
594 */
595 rulep->r_type = MONTH_NTH_DAY_OF_WEEK;
596 ++strp;
597 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR);
598 if (strp == NULL)
599 return NULL;
600 if (*strp++ != '.')
601 return NULL;
602 strp = getnum(strp, &rulep->r_week, 1, 5);
603 if (strp == NULL)
604 return NULL;
605 if (*strp++ != '.')
606 return NULL;
607 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1);
608 } else if (is_digit(*strp)) {
609 /*
610 ** Day of year.
611 */
612 rulep->r_type = DAY_OF_YEAR;
613 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1);
614 } else return NULL; /* invalid format */
615 if (strp == NULL)
616 return NULL;
617 if (*strp == '/') {
618 /*
619 ** Time specified.
620 */
621 ++strp;
622 strp = getsecs(strp, &rulep->r_time);
623 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */
624 return strp;
625 }
626
627 /*
628 ** Given the Epoch-relative time of January 1, 00:00:00 UTC, in a year, the
629 ** year, a rule, and the offset from UTC at the time that rule takes effect,
630 ** calculate the Epoch-relative time that rule takes effect.
631 */
632
633 static time_t
634 transtime(janfirst, year, rulep, offset)
635 const time_t janfirst;
636 const int year;
637 const struct rule * const rulep;
638 const long offset;
639 {
640 int leapyear;
641 time_t value;
642 int i;
643 int d, m1, yy0, yy1, yy2, dow;
644
645 INITIALIZE(value);
646 leapyear = isleap(year);
647 switch (rulep->r_type) {
648
649 case JULIAN_DAY:
650 /*
651 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap
652 ** years.
653 ** In non-leap years, or if the day number is 59 or less, just
654 ** add SECSPERDAY times the day number-1 to the time of
655 ** January 1, midnight, to get the day.
656 */
657 value = janfirst + (rulep->r_day - 1) * SECSPERDAY;
658 if (leapyear && rulep->r_day >= 60)
659 value += SECSPERDAY;
660 break;
661
662 case DAY_OF_YEAR:
663 /*
664 ** n - day of year.
665 ** Just add SECSPERDAY times the day number to the time of
666 ** January 1, midnight, to get the day.
667 */
668 value = janfirst + rulep->r_day * SECSPERDAY;
669 break;
670
671 case MONTH_NTH_DAY_OF_WEEK:
672 /*
673 ** Mm.n.d - nth "dth day" of month m.
674 */
675 value = janfirst;
676 for (i = 0; i < rulep->r_mon - 1; ++i)
677 value += mon_lengths[leapyear][i] * SECSPERDAY;
678
679 /*
680 ** Use Zeller's Congruence to get day-of-week of first day of
681 ** month.
682 */
683 m1 = (rulep->r_mon + 9) % 12 + 1;
684 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year;
685 yy1 = yy0 / 100;
686 yy2 = yy0 % 100;
687 dow = ((26 * m1 - 2) / 10 +
688 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7;
689 if (dow < 0)
690 dow += DAYSPERWEEK;
691
692 /*
693 ** "dow" is the day-of-week of the first day of the month. Get
694 ** the day-of-month (zero-origin) of the first "dow" day of the
695 ** month.
696 */
697 d = rulep->r_day - dow;
698 if (d < 0)
699 d += DAYSPERWEEK;
700 for (i = 1; i < rulep->r_week; ++i) {
701 if (d + DAYSPERWEEK >=
702 mon_lengths[leapyear][rulep->r_mon - 1])
703 break;
704 d += DAYSPERWEEK;
705 }
706
707 /*
708 ** "d" is the day-of-month (zero-origin) of the day we want.
709 */
710 value += d * SECSPERDAY;
711 break;
712 }
713
714 /*
715 ** "value" is the Epoch-relative time of 00:00:00 UTC on the day in
716 ** question. To get the Epoch-relative time of the specified local
717 ** time on that day, add the transition time and the current offset
718 ** from UTC.
719 */
720 return value + rulep->r_time + offset;
721 }
722
723 /*
724 ** Given a POSIX section 8-style TZ string, fill in the rule tables as
725 ** appropriate.
726 */
727
728 static int
729 tzparse(name, sp, lastditch)
730 const char * name;
731 struct state * const sp;
732 const int lastditch;
733 {
734 const char * stdname;
735 const char * dstname;
736 size_t stdlen;
737 size_t dstlen;
738 long stdoffset;
739 long dstoffset;
740 time_t * atp;
741 unsigned char * typep;
742 char * cp;
743 int load_result;
744
745 INITIALIZE(dstname);
746 stdname = name;
747 if (lastditch) {
748 stdlen = strlen(name); /* length of standard zone name */
749 name += stdlen;
750 if (stdlen >= sizeof sp->chars)
751 stdlen = (sizeof sp->chars) - 1;
752 stdoffset = 0;
753 } else {
754 name = getzname(name);
755 stdlen = name - stdname;
756 if (stdlen < 3)
757 return -1;
758 if (*name == '\0')
759 return -1; /* was "stdoffset = 0;" */
760 else {
761 name = getoffset(name, &stdoffset);
762 if (name == NULL)
763 return -1;
764 }
765 }
766 load_result = tzload(TZDEFRULES, sp);
767 if (load_result != 0)
768 sp->leapcnt = 0; /* so, we're off a little */
769 if (*name != '\0') {
770 dstname = name;
771 name = getzname(name);
772 dstlen = name - dstname; /* length of DST zone name */
773 if (dstlen < 3)
774 return -1;
775 if (*name != '\0' && *name != ',' && *name != ';') {
776 name = getoffset(name, &dstoffset);
777 if (name == NULL)
778 return -1;
779 } else dstoffset = stdoffset - SECSPERHOUR;
780 if (*name == '\0' && load_result != 0)
781 name = TZDEFRULESTRING;
782 if (*name == ',' || *name == ';') {
783 struct rule start;
784 struct rule end;
785 int year;
786 time_t janfirst;
787 time_t starttime;
788 time_t endtime;
789
790 ++name;
791 if ((name = getrule(name, &start)) == NULL)
792 return -1;
793 if (*name++ != ',')
794 return -1;
795 if ((name = getrule(name, &end)) == NULL)
796 return -1;
797 if (*name != '\0')
798 return -1;
799 sp->typecnt = 2; /* standard time and DST */
800 /*
801 ** Two transitions per year, from EPOCH_YEAR to 2037.
802 */
803 sp->timecnt = 2 * (2037 - EPOCH_YEAR + 1);
804 if (sp->timecnt > TZ_MAX_TIMES)
805 return -1;
806 sp->ttis[0].tt_gmtoff = -dstoffset;
807 sp->ttis[0].tt_isdst = 1;
808 sp->ttis[0].tt_abbrind = stdlen + 1;
809 sp->ttis[1].tt_gmtoff = -stdoffset;
810 sp->ttis[1].tt_isdst = 0;
811 sp->ttis[1].tt_abbrind = 0;
812 atp = sp->ats;
813 typep = sp->types;
814 janfirst = 0;
815 for (year = EPOCH_YEAR; year <= 2037; ++year) {
816 starttime = transtime(janfirst, year, &start,
817 stdoffset);
818 endtime = transtime(janfirst, year, &end,
819 dstoffset);
820 if (starttime > endtime) {
821 *atp++ = endtime;
822 *typep++ = 1; /* DST ends */
823 *atp++ = starttime;
824 *typep++ = 0; /* DST begins */
825 } else {
826 *atp++ = starttime;
827 *typep++ = 0; /* DST begins */
828 *atp++ = endtime;
829 *typep++ = 1; /* DST ends */
830 }
831 janfirst += year_lengths[isleap(year)] *
832 SECSPERDAY;
833 }
834 } else {
835 long theirstdoffset;
836 long theirdstoffset;
837 long theiroffset;
838 int isdst;
839 int i;
840 int j;
841
842 if (*name != '\0')
843 return -1;
844 /*
845 ** Initial values of theirstdoffset and theirdstoffset.
846 */
847 theirstdoffset = 0;
848 for (i = 0; i < sp->timecnt; ++i) {
849 j = sp->types[i];
850 if (!sp->ttis[j].tt_isdst) {
851 theirstdoffset =
852 -sp->ttis[j].tt_gmtoff;
853 break;
854 }
855 }
856 theirdstoffset = 0;
857 for (i = 0; i < sp->timecnt; ++i) {
858 j = sp->types[i];
859 if (sp->ttis[j].tt_isdst) {
860 theirdstoffset =
861 -sp->ttis[j].tt_gmtoff;
862 break;
863 }
864 }
865 /*
866 ** Initially we're assumed to be in standard time.
867 */
868 isdst = FALSE;
869 theiroffset = theirstdoffset;
870 /*
871 ** Now juggle transition times and types
872 ** tracking offsets as you do.
873 */
874 for (i = 0; i < sp->timecnt; ++i) {
875 j = sp->types[i];
876 sp->types[i] = sp->ttis[j].tt_isdst;
877 if (sp->ttis[j].tt_ttisgmt) {
878 /* No adjustment to transition time */
879 } else {
880 /*
881 ** If summer time is in effect, and the
882 ** transition time was not specified as
883 ** standard time, add the summer time
884 ** offset to the transition time;
885 ** otherwise, add the standard time
886 ** offset to the transition time.
887 */
888 /*
889 ** Transitions from DST to DDST
890 ** will effectively disappear since
891 ** POSIX provides for only one DST
892 ** offset.
893 */
894 if (isdst && !sp->ttis[j].tt_ttisstd) {
895 sp->ats[i] += dstoffset -
896 theirdstoffset;
897 } else {
898 sp->ats[i] += stdoffset -
899 theirstdoffset;
900 }
901 }
902 theiroffset = -sp->ttis[j].tt_gmtoff;
903 if (sp->ttis[j].tt_isdst)
904 theirdstoffset = theiroffset;
905 else theirstdoffset = theiroffset;
906 }
907 /*
908 ** Finally, fill in ttis.
909 ** ttisstd and ttisgmt need not be handled.
910 */
911 sp->ttis[0].tt_gmtoff = -stdoffset;
912 sp->ttis[0].tt_isdst = FALSE;
913 sp->ttis[0].tt_abbrind = 0;
914 sp->ttis[1].tt_gmtoff = -dstoffset;
915 sp->ttis[1].tt_isdst = TRUE;
916 sp->ttis[1].tt_abbrind = stdlen + 1;
917 sp->typecnt = 2;
918 }
919 } else {
920 dstlen = 0;
921 sp->typecnt = 1; /* only standard time */
922 sp->timecnt = 0;
923 sp->ttis[0].tt_gmtoff = -stdoffset;
924 sp->ttis[0].tt_isdst = 0;
925 sp->ttis[0].tt_abbrind = 0;
926 }
927 sp->charcnt = stdlen + 1;
928 if (dstlen != 0)
929 sp->charcnt += dstlen + 1;
930 if ((size_t) sp->charcnt > sizeof sp->chars)
931 return -1;
932 cp = sp->chars;
933 (void) strncpy(cp, stdname, stdlen);
934 cp += stdlen;
935 *cp++ = '\0';
936 if (dstlen != 0) {
937 (void) strncpy(cp, dstname, dstlen);
938 *(cp + dstlen) = '\0';
939 }
940 return 0;
941 }
942
943 static void
944 gmtload(sp)
945 struct state * const sp;
946 {
947 if (tzload(gmt, sp) != 0)
948 (void) tzparse(gmt, sp, TRUE);
949 }
950
951 static void
952 tzsetwall_basic(void)
953 {
954 if (lcl_is_set < 0)
955 return;
956 lcl_is_set = -1;
957
958 #ifdef ALL_STATE
959 if (lclptr == NULL) {
960 lclptr = (struct state *) malloc(sizeof *lclptr);
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 void
973 tzsetwall(void)
974 {
975 _MUTEX_LOCK(&lcl_mutex);
976 tzsetwall_basic();
977 _MUTEX_UNLOCK(&lcl_mutex);
978 }
979
980 static void
981 tzset_basic(void)
982 {
983 const char * name;
984
985 name = getenv("TZ");
986 if (name == NULL) {
987 tzsetwall_basic();
988 return;
989 }
990
991 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0)
992 return;
993 lcl_is_set = strlen(name) < sizeof lcl_TZname;
994 if (lcl_is_set)
995 (void) strcpy(lcl_TZname, name);
996
997 #ifdef ALL_STATE
998 if (lclptr == NULL) {
999 lclptr = (struct state *) malloc(sizeof *lclptr);
1000 if (lclptr == NULL) {
1001 settzname(); /* all we can do */
1002 return;
1003 }
1004 }
1005 #endif /* defined ALL_STATE */
1006 if (*name == '\0') {
1007 /*
1008 ** User wants it fast rather than right.
1009 */
1010 lclptr->leapcnt = 0; /* so, we're off a little */
1011 lclptr->timecnt = 0;
1012 lclptr->typecnt = 0;
1013 lclptr->ttis[0].tt_isdst = 0;
1014 lclptr->ttis[0].tt_gmtoff = 0;
1015 lclptr->ttis[0].tt_abbrind = 0;
1016 (void) strcpy(lclptr->chars, gmt);
1017 } else if (tzload(name, lclptr) != 0)
1018 if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0)
1019 (void) gmtload(lclptr);
1020 settzname();
1021 }
1022
1023 void
1024 tzset(void)
1025 {
1026 _MUTEX_LOCK(&lcl_mutex);
1027 tzset_basic();
1028 _MUTEX_UNLOCK(&lcl_mutex);
1029 }
1030
1031 /*
1032 ** The easy way to behave "as if no library function calls" localtime
1033 ** is to not call it--so we drop its guts into "localsub", which can be
1034 ** freely called. (And no, the PANS doesn't require the above behavior--
1035 ** but it *is* desirable.)
1036 **
1037 ** The unused offset argument is for the benefit of mktime variants.
1038 */
1039
1040 /*ARGSUSED*/
1041 static void
1042 localsub(timep, offset, tmp)
1043 const time_t * const timep;
1044 const long offset;
1045 struct tm * const tmp;
1046 {
1047 struct state * sp;
1048 const struct ttinfo * ttisp;
1049 int i;
1050 const time_t t = *timep;
1051
1052 sp = lclptr;
1053 #ifdef ALL_STATE
1054 if (sp == NULL) {
1055 gmtsub(timep, offset, tmp);
1056 return;
1057 }
1058 #endif /* defined ALL_STATE */
1059 if (sp->timecnt == 0 || t < sp->ats[0]) {
1060 i = 0;
1061 while (sp->ttis[i].tt_isdst)
1062 if (++i >= sp->typecnt) {
1063 i = 0;
1064 break;
1065 }
1066 } else {
1067 for (i = 1; i < sp->timecnt; ++i)
1068 if (t < sp->ats[i])
1069 break;
1070 i = sp->types[i - 1];
1071 }
1072 ttisp = &sp->ttis[i];
1073 /*
1074 ** To get (wrong) behavior that's compatible with System V Release 2.0
1075 ** you'd replace the statement below with
1076 ** t += ttisp->tt_gmtoff;
1077 ** timesub(&t, 0L, sp, tmp);
1078 */
1079 timesub(&t, ttisp->tt_gmtoff, sp, tmp);
1080 tmp->tm_isdst = ttisp->tt_isdst;
1081 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind];
1082 #ifdef TM_ZONE
1083 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind];
1084 #endif /* defined TM_ZONE */
1085 }
1086
1087 struct tm *
1088 localtime(timep)
1089 const time_t * const timep;
1090 {
1091 static pthread_mutex_t localtime_mutex = PTHREAD_MUTEX_INITIALIZER;
1092 static pthread_key_t localtime_key = -1;
1093 struct tm *p_tm;
1094
1095 if (__isthreaded != 0) {
1096 _pthread_mutex_lock(&localtime_mutex);
1097 if (localtime_key < 0) {
1098 if (_pthread_key_create(&localtime_key, free) < 0) {
1099 _pthread_mutex_unlock(&localtime_mutex);
1100 return(NULL);
1101 }
1102 }
1103 _pthread_mutex_unlock(&localtime_mutex);
1104 p_tm = _pthread_getspecific(localtime_key);
1105 if (p_tm == NULL) {
1106 if ((p_tm = (struct tm *)malloc(sizeof(struct tm)))
1107 == NULL)
1108 return(NULL);
1109 _pthread_setspecific(localtime_key, p_tm);
1110 }
1111 _pthread_mutex_lock(&lcl_mutex);
1112 tzset_basic();
1113 localsub(timep, 0L, p_tm);
1114 _pthread_mutex_unlock(&lcl_mutex);
1115 return(p_tm);
1116 } else {
1117 tzset_basic();
1118 localsub(timep, 0L, &tm);
1119 return(&tm);
1120 }
1121 }
1122
1123 /*
1124 ** Re-entrant version of localtime.
1125 */
1126
1127 struct tm *
1128 localtime_r(timep, tm)
1129 const time_t * const timep;
1130 struct tm * tm;
1131 {
1132 _MUTEX_LOCK(&lcl_mutex);
1133 tzset_basic();
1134 localsub(timep, 0L, tm);
1135 _MUTEX_UNLOCK(&lcl_mutex);
1136 return tm;
1137 }
1138
1139 /*
1140 ** gmtsub is to gmtime as localsub is to localtime.
1141 */
1142
1143 static void
1144 gmtsub(timep, offset, tmp)
1145 const time_t * const timep;
1146 const long offset;
1147 struct tm * const tmp;
1148 {
1149 _MUTEX_LOCK(&gmt_mutex);
1150 if (!gmt_is_set) {
1151 gmt_is_set = TRUE;
1152 #ifdef ALL_STATE
1153 gmtptr = (struct state *) malloc(sizeof *gmtptr);
1154 if (gmtptr != NULL)
1155 #endif /* defined ALL_STATE */
1156 gmtload(gmtptr);
1157 }
1158 _MUTEX_UNLOCK(&gmt_mutex);
1159 timesub(timep, offset, gmtptr, tmp);
1160 #ifdef TM_ZONE
1161 /*
1162 ** Could get fancy here and deliver something such as
1163 ** "UTC+xxxx" or "UTC-xxxx" if offset is non-zero,
1164 ** but this is no time for a treasure hunt.
1165 */
1166 if (offset != 0)
1167 tmp->TM_ZONE = wildabbr;
1168 else {
1169 #ifdef ALL_STATE
1170 if (gmtptr == NULL)
1171 tmp->TM_ZONE = gmt;
1172 else tmp->TM_ZONE = gmtptr->chars;
1173 #endif /* defined ALL_STATE */
1174 #ifndef ALL_STATE
1175 tmp->TM_ZONE = gmtptr->chars;
1176 #endif /* State Farm */
1177 }
1178 #endif /* defined TM_ZONE */
1179 }
1180
1181 struct tm *
1182 gmtime(timep)
1183 const time_t * const timep;
1184 {
1185 static pthread_mutex_t gmtime_mutex = PTHREAD_MUTEX_INITIALIZER;
1186 static pthread_key_t gmtime_key = -1;
1187 struct tm *p_tm;
1188
1189 if (__isthreaded != 0) {
1190 _pthread_mutex_lock(&gmtime_mutex);
1191 if (gmtime_key < 0) {
1192 if (_pthread_key_create(&gmtime_key, free) < 0) {
1193 _pthread_mutex_unlock(&gmtime_mutex);
1194 return(NULL);
1195 }
1196 }
1197 _pthread_mutex_unlock(&gmtime_mutex);
1198 /*
1199 * Changed to follow POSIX.1 threads standard, which
1200 * is what BSD currently has.
1201 */
1202 if ((p_tm = _pthread_getspecific(gmtime_key)) == NULL) {
1203 if ((p_tm = (struct tm *)malloc(sizeof(struct tm)))
1204 == NULL) {
1205 return(NULL);
1206 }
1207 _pthread_setspecific(gmtime_key, p_tm);
1208 }
1209 gmtsub(timep, 0L, p_tm);
1210 return(p_tm);
1211 }
1212 else {
1213 gmtsub(timep, 0L, &tm);
1214 return(&tm);
1215 }
1216 }
1217
1218 /*
1219 * Re-entrant version of gmtime.
1220 */
1221
1222 struct tm *
1223 gmtime_r(timep, tm)
1224 const time_t * const timep;
1225 struct tm * tm;
1226 {
1227 gmtsub(timep, 0L, tm);
1228 return tm;
1229 }
1230
1231 #ifdef STD_INSPIRED
1232
1233 struct tm *
1234 offtime(timep, offset)
1235 const time_t * const timep;
1236 const long offset;
1237 {
1238 gmtsub(timep, offset, &tm);
1239 return &tm;
1240 }
1241
1242 #endif /* defined STD_INSPIRED */
1243
1244 static void
1245 timesub(timep, offset, sp, tmp)
1246 const time_t * const timep;
1247 const long offset;
1248 const struct state * const sp;
1249 struct tm * const tmp;
1250 {
1251 const struct lsinfo * lp;
1252 long days;
1253 long rem;
1254 long y;
1255 int yleap;
1256 const int * ip;
1257 long corr;
1258 int hit;
1259 int i;
1260
1261 corr = 0;
1262 hit = 0;
1263 #ifdef ALL_STATE
1264 i = (sp == NULL) ? 0 : sp->leapcnt;
1265 #endif /* defined ALL_STATE */
1266 #ifndef ALL_STATE
1267 i = sp->leapcnt;
1268 #endif /* State Farm */
1269 while (--i >= 0) {
1270 lp = &sp->lsis[i];
1271 if (*timep >= lp->ls_trans) {
1272 if (*timep == lp->ls_trans) {
1273 hit = ((i == 0 && lp->ls_corr > 0) ||
1274 lp->ls_corr > sp->lsis[i - 1].ls_corr);
1275 if (hit)
1276 while (i > 0 &&
1277 sp->lsis[i].ls_trans ==
1278 sp->lsis[i - 1].ls_trans + 1 &&
1279 sp->lsis[i].ls_corr ==
1280 sp->lsis[i - 1].ls_corr + 1) {
1281 ++hit;
1282 --i;
1283 }
1284 }
1285 corr = lp->ls_corr;
1286 break;
1287 }
1288 }
1289 days = *timep / SECSPERDAY;
1290 rem = *timep % SECSPERDAY;
1291 #ifdef mc68k
1292 if (*timep == 0x80000000) {
1293 /*
1294 ** A 3B1 muffs the division on the most negative number.
1295 */
1296 days = -24855;
1297 rem = -11648;
1298 }
1299 #endif /* defined mc68k */
1300 rem += (offset - corr);
1301 while (rem < 0) {
1302 rem += SECSPERDAY;
1303 --days;
1304 }
1305 while (rem >= SECSPERDAY) {
1306 rem -= SECSPERDAY;
1307 ++days;
1308 }
1309 tmp->tm_hour = (int) (rem / SECSPERHOUR);
1310 rem = rem % SECSPERHOUR;
1311 tmp->tm_min = (int) (rem / SECSPERMIN);
1312 /*
1313 ** A positive leap second requires a special
1314 ** representation. This uses "... ??:59:60" et seq.
1315 */
1316 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit;
1317 tmp->tm_wday = (int) ((EPOCH_WDAY + days) % DAYSPERWEEK);
1318 if (tmp->tm_wday < 0)
1319 tmp->tm_wday += DAYSPERWEEK;
1320 y = EPOCH_YEAR;
1321 #define LEAPS_THRU_END_OF(y) ((y) / 4 - (y) / 100 + (y) / 400)
1322 while (days < 0 || days >= (long) year_lengths[yleap = isleap(y)]) {
1323 long newy;
1324
1325 newy = y + days / DAYSPERNYEAR;
1326 if (days < 0)
1327 --newy;
1328 days -= (newy - y) * DAYSPERNYEAR +
1329 LEAPS_THRU_END_OF(newy - 1) -
1330 LEAPS_THRU_END_OF(y - 1);
1331 y = newy;
1332 }
1333 tmp->tm_year = y - TM_YEAR_BASE;
1334 tmp->tm_yday = (int) days;
1335 ip = mon_lengths[yleap];
1336 for (tmp->tm_mon = 0; days >= (long) ip[tmp->tm_mon]; ++(tmp->tm_mon))
1337 days = days - (long) ip[tmp->tm_mon];
1338 tmp->tm_mday = (int) (days + 1);
1339 tmp->tm_isdst = 0;
1340 #ifdef TM_GMTOFF
1341 tmp->TM_GMTOFF = offset;
1342 #endif /* defined TM_GMTOFF */
1343 }
1344
1345 char *
1346 ctime(timep)
1347 const time_t * const timep;
1348 {
1349 /*
1350 ** Section 4.12.3.2 of X3.159-1989 requires that
1351 ** The ctime function converts the calendar time pointed to by timer
1352 ** to local time in the form of a string. It is equivalent to
1353 ** asctime(localtime(timer))
1354 */
1355 return asctime(localtime(timep));
1356 }
1357
1358 char *
1359 ctime_r(timep, buf)
1360 const time_t * const timep;
1361 char * buf;
1362 {
1363 struct tm tm;
1364
1365 return asctime_r(localtime_r(timep, &tm), buf);
1366 }
1367
1368 /*
1369 ** Adapted from code provided by Robert Elz, who writes:
1370 ** The "best" way to do mktime I think is based on an idea of Bob
1371 ** Kridle's (so its said...) from a long time ago.
1372 ** [kridle@xinet.com as of 1996-01-16.]
1373 ** It does a binary search of the time_t space. Since time_t's are
1374 ** just 32 bits, its a max of 32 iterations (even at 64 bits it
1375 ** would still be very reasonable).
1376 */
1377
1378 #ifndef WRONG
1379 #define WRONG (-1)
1380 #endif /* !defined WRONG */
1381
1382 /*
1383 ** Simplified normalize logic courtesy Paul Eggert (eggert@twinsun.com).
1384 */
1385
1386 static int
1387 increment_overflow(number, delta)
1388 int * number;
1389 int delta;
1390 {
1391 int number0;
1392
1393 number0 = *number;
1394 *number += delta;
1395 return (*number < number0) != (delta < 0);
1396 }
1397
1398 static int
1399 normalize_overflow(tensptr, unitsptr, base)
1400 int * const tensptr;
1401 int * const unitsptr;
1402 const int base;
1403 {
1404 int tensdelta;
1405
1406 tensdelta = (*unitsptr >= 0) ?
1407 (*unitsptr / base) :
1408 (-1 - (-1 - *unitsptr) / base);
1409 *unitsptr -= tensdelta * base;
1410 return increment_overflow(tensptr, tensdelta);
1411 }
1412
1413 static int
1414 tmcomp(atmp, btmp)
1415 const struct tm * const atmp;
1416 const struct tm * const btmp;
1417 {
1418 int result;
1419
1420 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 &&
1421 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 &&
1422 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 &&
1423 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 &&
1424 (result = (atmp->tm_min - btmp->tm_min)) == 0)
1425 result = atmp->tm_sec - btmp->tm_sec;
1426 return result;
1427 }
1428
1429 static time_t
1430 time2sub(tmp, funcp, offset, okayp, do_norm_secs)
1431 struct tm * const tmp;
1432 void (* const funcp)(const time_t*, long, struct tm*);
1433 const long offset;
1434 int * const okayp;
1435 const int do_norm_secs;
1436 {
1437 const struct state * sp;
1438 int dir;
1439 int bits;
1440 int i, j ;
1441 int saved_seconds;
1442 time_t newt;
1443 time_t t;
1444 struct tm yourtm, mytm;
1445
1446 *okayp = FALSE;
1447 yourtm = *tmp;
1448 if (do_norm_secs) {
1449 if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec,
1450 SECSPERMIN))
1451 return WRONG;
1452 }
1453 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR))
1454 return WRONG;
1455 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY))
1456 return WRONG;
1457 if (normalize_overflow(&yourtm.tm_year, &yourtm.tm_mon, MONSPERYEAR))
1458 return WRONG;
1459 /*
1460 ** Turn yourtm.tm_year into an actual year number for now.
1461 ** It is converted back to an offset from TM_YEAR_BASE later.
1462 */
1463 if (increment_overflow(&yourtm.tm_year, TM_YEAR_BASE))
1464 return WRONG;
1465 while (yourtm.tm_mday <= 0) {
1466 if (increment_overflow(&yourtm.tm_year, -1))
1467 return WRONG;
1468 i = yourtm.tm_year + (1 < yourtm.tm_mon);
1469 yourtm.tm_mday += year_lengths[isleap(i)];
1470 }
1471 while (yourtm.tm_mday > DAYSPERLYEAR) {
1472 i = yourtm.tm_year + (1 < yourtm.tm_mon);
1473 yourtm.tm_mday -= year_lengths[isleap(i)];
1474 if (increment_overflow(&yourtm.tm_year, 1))
1475 return WRONG;
1476 }
1477 for ( ; ; ) {
1478 i = mon_lengths[isleap(yourtm.tm_year)][yourtm.tm_mon];
1479 if (yourtm.tm_mday <= i)
1480 break;
1481 yourtm.tm_mday -= i;
1482 if (++yourtm.tm_mon >= MONSPERYEAR) {
1483 yourtm.tm_mon = 0;
1484 if (increment_overflow(&yourtm.tm_year, 1))
1485 return WRONG;
1486 }
1487 }
1488 if (increment_overflow(&yourtm.tm_year, -TM_YEAR_BASE))
1489 return WRONG;
1490 /* Don't go below 1900 for POLA */
1491 if (yourtm.tm_year < 0)
1492 return WRONG;
1493 if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN)
1494 saved_seconds = 0;
1495 else if (yourtm.tm_year + TM_YEAR_BASE < EPOCH_YEAR) {
1496 /*
1497 ** We can't set tm_sec to 0, because that might push the
1498 ** time below the minimum representable time.
1499 ** Set tm_sec to 59 instead.
1500 ** This assumes that the minimum representable time is
1501 ** not in the same minute that a leap second was deleted from,
1502 ** which is a safer assumption than using 58 would be.
1503 */
1504 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN))
1505 return WRONG;
1506 saved_seconds = yourtm.tm_sec;
1507 yourtm.tm_sec = SECSPERMIN - 1;
1508 } else {
1509 saved_seconds = yourtm.tm_sec;
1510 yourtm.tm_sec = 0;
1511 }
1512 /*
1513 ** Divide the search space in half
1514 ** (this works whether time_t is signed or unsigned).
1515 */
1516 bits = TYPE_BIT(time_t) - 1;
1517 /*
1518 ** If we have more than this, we will overflow tm_year for tmcomp().
1519 ** We should really return an error if we cannot represent it.
1520 */
1521 if (bits > 56)
1522 bits = 56;
1523 /*
1524 ** If time_t is signed, then 0 is just above the median,
1525 ** assuming two's complement arithmetic.
1526 ** If time_t is unsigned, then (1 << bits) is just above the median.
1527 */
1528 t = TYPE_SIGNED(time_t) ? 0 : (((time_t) 1) << bits);
1529 for ( ; ; ) {
1530 (*funcp)(&t, offset, &mytm);
1531 dir = tmcomp(&mytm, &yourtm);
1532 if (dir != 0) {
1533 if (bits-- < 0)
1534 return WRONG;
1535 if (bits < 0)
1536 --t; /* may be needed if new t is minimal */
1537 else if (dir > 0)
1538 t -= ((time_t) 1) << bits;
1539 else t += ((time_t) 1) << bits;
1540 continue;
1541 }
1542 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst)
1543 break;
1544 /*
1545 ** Right time, wrong type.
1546 ** Hunt for right time, right type.
1547 ** It's okay to guess wrong since the guess
1548 ** gets checked.
1549 */
1550 sp = (funcp == localsub) ? lclptr : gmtptr;
1551 #ifdef ALL_STATE
1552 if (sp == NULL)
1553 return WRONG;
1554 #endif /* defined ALL_STATE */
1555 for (i = sp->typecnt - 1; i >= 0; --i) {
1556 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst)
1557 continue;
1558 for (j = sp->typecnt - 1; j >= 0; --j) {
1559 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst)
1560 continue;
1561 newt = t + sp->ttis[j].tt_gmtoff -
1562 sp->ttis[i].tt_gmtoff;
1563 (*funcp)(&newt, offset, &mytm);
1564 if (tmcomp(&mytm, &yourtm) != 0)
1565 continue;
1566 if (mytm.tm_isdst != yourtm.tm_isdst)
1567 continue;
1568 /*
1569 ** We have a match.
1570 */
1571 t = newt;
1572 goto label;
1573 }
1574 }
1575 return WRONG;
1576 }
1577 label:
1578 newt = t + saved_seconds;
1579 if ((newt < t) != (saved_seconds < 0))
1580 return WRONG;
1581 t = newt;
1582 (*funcp)(&t, offset, tmp);
1583 *okayp = TRUE;
1584 return t;
1585 }
1586
1587 static time_t
1588 time2(tmp, funcp, offset, okayp)
1589 struct tm * const tmp;
1590 void (* const funcp)(const time_t*, long, struct tm*);
1591 const long offset;
1592 int * const okayp;
1593 {
1594 time_t t;
1595
1596 /*
1597 ** First try without normalization of seconds
1598 ** (in case tm_sec contains a value associated with a leap second).
1599 ** If that fails, try with normalization of seconds.
1600 */
1601 t = time2sub(tmp, funcp, offset, okayp, FALSE);
1602 return *okayp ? t : time2sub(tmp, funcp, offset, okayp, TRUE);
1603 }
1604
1605 static time_t
1606 time1(tmp, funcp, offset)
1607 struct tm * const tmp;
1608 void (* const funcp)(const time_t *, long, struct tm *);
1609 const long offset;
1610 {
1611 time_t t;
1612 const struct state * sp;
1613 int samei, otheri;
1614 int sameind, otherind;
1615 int i;
1616 int nseen;
1617 int seen[TZ_MAX_TYPES];
1618 int types[TZ_MAX_TYPES];
1619 int okay;
1620
1621 if (tmp->tm_isdst > 1)
1622 tmp->tm_isdst = 1;
1623 t = time2(tmp, funcp, offset, &okay);
1624 #ifdef PCTS
1625 /*
1626 ** PCTS code courtesy Grant Sullivan (grant@osf.org).
1627 */
1628 if (okay)
1629 return t;
1630 if (tmp->tm_isdst < 0)
1631 tmp->tm_isdst = 0; /* reset to std and try again */
1632 #endif /* defined PCTS */
1633 #ifndef PCTS
1634 if (okay || tmp->tm_isdst < 0)
1635 return t;
1636 #endif /* !defined PCTS */
1637 /*
1638 ** We're supposed to assume that somebody took a time of one type
1639 ** and did some math on it that yielded a "struct tm" that's bad.
1640 ** We try to divine the type they started from and adjust to the
1641 ** type they need.
1642 */
1643 sp = (funcp == localsub) ? lclptr : gmtptr;
1644 #ifdef ALL_STATE
1645 if (sp == NULL)
1646 return WRONG;
1647 #endif /* defined ALL_STATE */
1648 for (i = 0; i < sp->typecnt; ++i)
1649 seen[i] = FALSE;
1650 nseen = 0;
1651 for (i = sp->timecnt - 1; i >= 0; --i)
1652 if (!seen[sp->types[i]]) {
1653 seen[sp->types[i]] = TRUE;
1654 types[nseen++] = sp->types[i];
1655 }
1656 for (sameind = 0; sameind < nseen; ++sameind) {
1657 samei = types[sameind];
1658 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst)
1659 continue;
1660 for (otherind = 0; otherind < nseen; ++otherind) {
1661 otheri = types[otherind];
1662 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst)
1663 continue;
1664 tmp->tm_sec += sp->ttis[otheri].tt_gmtoff -
1665 sp->ttis[samei].tt_gmtoff;
1666 tmp->tm_isdst = !tmp->tm_isdst;
1667 t = time2(tmp, funcp, offset, &okay);
1668 if (okay)
1669 return t;
1670 tmp->tm_sec -= sp->ttis[otheri].tt_gmtoff -
1671 sp->ttis[samei].tt_gmtoff;
1672 tmp->tm_isdst = !tmp->tm_isdst;
1673 }
1674 }
1675 return WRONG;
1676 }
1677
1678 time_t
1679 mktime(tmp)
1680 struct tm * const tmp;
1681 {
1682 time_t mktime_return_value;
1683 _MUTEX_LOCK(&lcl_mutex);
1684 tzset_basic();
1685 mktime_return_value = time1(tmp, localsub, 0L);
1686 _MUTEX_UNLOCK(&lcl_mutex);
1687 return(mktime_return_value);
1688 }
1689
1690 #ifdef STD_INSPIRED
1691
1692 time_t
1693 timelocal(tmp)
1694 struct tm * const tmp;
1695 {
1696 tmp->tm_isdst = -1; /* in case it wasn't initialized */
1697 return mktime(tmp);
1698 }
1699
1700 time_t
1701 timegm(tmp)
1702 struct tm * const tmp;
1703 {
1704 tmp->tm_isdst = 0;
1705 return time1(tmp, gmtsub, 0L);
1706 }
1707
1708 time_t
1709 timeoff(tmp, offset)
1710 struct tm * const tmp;
1711 const long offset;
1712 {
1713 tmp->tm_isdst = 0;
1714 return time1(tmp, gmtsub, offset);
1715 }
1716
1717 #endif /* defined STD_INSPIRED */
1718
1719 #ifdef CMUCS
1720
1721 /*
1722 ** The following is supplied for compatibility with
1723 ** previous versions of the CMUCS runtime library.
1724 */
1725
1726 long
1727 gtime(tmp)
1728 struct tm * const tmp;
1729 {
1730 const time_t t = mktime(tmp);
1731
1732 if (t == WRONG)
1733 return -1;
1734 return t;
1735 }
1736
1737 #endif /* defined CMUCS */
1738
1739 /*
1740 ** XXX--is the below the right way to conditionalize??
1741 */
1742
1743 #ifdef STD_INSPIRED
1744
1745 /*
1746 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599
1747 ** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which
1748 ** is not the case if we are accounting for leap seconds.
1749 ** So, we provide the following conversion routines for use
1750 ** when exchanging timestamps with POSIX conforming systems.
1751 */
1752
1753 static long
1754 leapcorr(timep)
1755 time_t * timep;
1756 {
1757 struct state * sp;
1758 struct lsinfo * lp;
1759 int i;
1760
1761 sp = lclptr;
1762 i = sp->leapcnt;
1763 while (--i >= 0) {
1764 lp = &sp->lsis[i];
1765 if (*timep >= lp->ls_trans)
1766 return lp->ls_corr;
1767 }
1768 return 0;
1769 }
1770
1771 time_t
1772 time2posix(t)
1773 time_t t;
1774 {
1775 tzset();
1776 return t - leapcorr(&t);
1777 }
1778
1779 time_t
1780 posix2time(t)
1781 time_t t;
1782 {
1783 time_t x;
1784 time_t y;
1785
1786 tzset();
1787 /*
1788 ** For a positive leap second hit, the result
1789 ** is not unique. For a negative leap second
1790 ** hit, the corresponding time doesn't exist,
1791 ** so we return an adjacent second.
1792 */
1793 x = t + leapcorr(&t);
1794 y = x - leapcorr(&x);
1795 if (y < t) {
1796 do {
1797 x++;
1798 y = x - leapcorr(&x);
1799 } while (y < t);
1800 if (t != y)
1801 return x - 1;
1802 } else if (y > t) {
1803 do {
1804 --x;
1805 y = x - leapcorr(&x);
1806 } while (y > t);
1807 if (t != y)
1808 return x + 1;
1809 }
1810 return x;
1811 }
1812
1813 #endif /* defined STD_INSPIRED */
mirror of libc