]> 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-320.tar.gz
[apple/libc.git] / stdtime / FreeBSD / localtime.c
1 /*
2 ** This file is in the public domain, so clarified as of
3 ** June 5, 1996 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 7.57";
10 #endif /* !defined NOID */
11 #endif /* !defined lint */
12 __FBSDID("$FreeBSD: src/lib/libc/stdtime/localtime.c,v 1.36 2003/02/16 17:29:11 nectar 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 static const char gmt[] = "GMT";
74
75 struct ttinfo { /* time type information */
76 long tt_gmtoff; /* GMT offset in seconds */
77 int tt_isdst; /* used to set tm_isdst */
78 int tt_abbrind; /* abbreviation list index */
79 int tt_ttisstd; /* TRUE if transition is std time */
80 int tt_ttisgmt; /* TRUE if transition is GMT */
81 };
82
83 struct lsinfo { /* leap second information */
84 time_t ls_trans; /* transition time */
85 long ls_corr; /* correction to apply */
86 };
87
88 #define BIGGEST(a, b) (((a) > (b)) ? (a) : (b))
89
90 #ifdef TZNAME_MAX
91 #define MY_TZNAME_MAX TZNAME_MAX
92 #endif /* defined TZNAME_MAX */
93 #ifndef TZNAME_MAX
94 #define MY_TZNAME_MAX 255
95 #endif /* !defined TZNAME_MAX */
96
97 struct state {
98 int leapcnt;
99 int timecnt;
100 int typecnt;
101 int charcnt;
102 time_t ats[TZ_MAX_TIMES];
103 unsigned char types[TZ_MAX_TIMES];
104 struct ttinfo ttis[TZ_MAX_TYPES];
105 char chars[BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt),
106 (2 * (MY_TZNAME_MAX + 1)))];
107 struct lsinfo lsis[TZ_MAX_LEAPS];
108 };
109
110 struct rule {
111 int r_type; /* type of rule--see below */
112 int r_day; /* day number of rule */
113 int r_week; /* week number of rule */
114 int r_mon; /* month number of rule */
115 long r_time; /* transition time of rule */
116 };
117
118 #define JULIAN_DAY 0 /* Jn - Julian day */
119 #define DAY_OF_YEAR 1 /* n - day of year */
120 #define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */
121
122 /*
123 ** Prototypes for static functions.
124 */
125
126 static long detzcode(const char * codep);
127 static const char * getzname(const char * strp);
128 static const char * getnum(const char * strp, int * nump, int min,
129 int max);
130 static const char * getsecs(const char * strp, long * secsp);
131 static const char * getoffset(const char * strp, long * offsetp);
132 static const char * getrule(const char * strp, struct rule * rulep);
133 static void gmtload(struct state * sp);
134 static void gmtsub(const time_t * timep, long offset,
135 struct tm * tmp);
136 static void localsub(const time_t * timep, long offset,
137 struct tm * tmp);
138 static int increment_overflow(int * number, int delta);
139 static int normalize_overflow(int * tensptr, int * unitsptr,
140 int base);
141 static void settzname(void);
142 static time_t time1(struct tm * tmp,
143 void(*funcp) (const time_t *,
144 long, struct tm *),
145 long offset);
146 static time_t time2(struct tm *tmp,
147 void(*funcp) (const time_t *,
148 long, struct tm*),
149 long offset, int * okayp);
150 static void timesub(const time_t * timep, long offset,
151 const struct state * sp, struct tm * tmp);
152 static int tmcomp(const struct tm * atmp,
153 const struct tm * btmp);
154 static time_t transtime(time_t janfirst, int year,
155 const struct rule * rulep, long offset);
156 static int tzload(const char * name, struct state * sp);
157 static int tzparse(const char * name, struct state * sp,
158 int lastditch);
159
160 #ifdef ALL_STATE
161 static struct state * lclptr;
162 static struct state * gmtptr;
163 #endif /* defined ALL_STATE */
164
165 #ifndef ALL_STATE
166 static struct state lclmem;
167 static struct state gmtmem;
168 #define lclptr (&lclmem)
169 #define gmtptr (&gmtmem)
170 #endif /* State Farm */
171
172 #ifndef TZ_STRLEN_MAX
173 #define TZ_STRLEN_MAX 255
174 #endif /* !defined TZ_STRLEN_MAX */
175
176 static char lcl_TZname[TZ_STRLEN_MAX + 1];
177 static int lcl_is_set;
178 static int gmt_is_set;
179 static pthread_mutex_t lcl_mutex = PTHREAD_MUTEX_INITIALIZER;
180 static pthread_mutex_t gmt_mutex = PTHREAD_MUTEX_INITIALIZER;
181
182 char * tzname[2] = {
183 wildabbr,
184 wildabbr
185 };
186
187 /*
188 ** Section 4.12.3 of X3.159-1989 requires that
189 ** Except for the strftime function, these functions [asctime,
190 ** ctime, gmtime, localtime] return values in one of two static
191 ** objects: a broken-down time structure and an array of char.
192 ** Thanks to Paul Eggert (eggert@twinsun.com) for noting this.
193 */
194
195 static struct tm tm;
196
197 #ifdef USG_COMPAT
198 time_t timezone = 0;
199 int daylight = 0;
200 #endif /* defined USG_COMPAT */
201
202 #ifdef ALTZONE
203 time_t altzone = 0;
204 #endif /* defined ALTZONE */
205
206 static long
207 detzcode(codep)
208 const char * const codep;
209 {
210 long result;
211 int i;
212
213 result = (codep[0] & 0x80) ? ~0L : 0L;
214 for (i = 0; i < 4; ++i)
215 result = (result << 8) | (codep[i] & 0xff);
216 return result;
217 }
218
219 static void
220 settzname(void)
221 {
222 struct state * sp = lclptr;
223 int i;
224
225 tzname[0] = wildabbr;
226 tzname[1] = wildabbr;
227 #ifdef USG_COMPAT
228 daylight = 0;
229 timezone = 0;
230 #endif /* defined USG_COMPAT */
231 #ifdef ALTZONE
232 altzone = 0;
233 #endif /* defined ALTZONE */
234 #ifdef ALL_STATE
235 if (sp == NULL) {
236 tzname[0] = tzname[1] = gmt;
237 return;
238 }
239 #endif /* defined ALL_STATE */
240 for (i = 0; i < sp->typecnt; ++i) {
241 const struct ttinfo * const ttisp = &sp->ttis[i];
242
243 tzname[ttisp->tt_isdst] =
244 &sp->chars[ttisp->tt_abbrind];
245 #ifdef USG_COMPAT
246 if (ttisp->tt_isdst)
247 daylight = 1;
248 if (i == 0 || !ttisp->tt_isdst)
249 timezone = -(ttisp->tt_gmtoff);
250 #endif /* defined USG_COMPAT */
251 #ifdef ALTZONE
252 if (i == 0 || ttisp->tt_isdst)
253 altzone = -(ttisp->tt_gmtoff);
254 #endif /* defined ALTZONE */
255 }
256 /*
257 ** And to get the latest zone names into tzname. . .
258 */
259 for (i = 0; i < sp->timecnt; ++i) {
260 const struct ttinfo * const ttisp =
261 &sp->ttis[
262 sp->types[i]];
263
264 tzname[ttisp->tt_isdst] =
265 &sp->chars[ttisp->tt_abbrind];
266 }
267 }
268
269 static int
270 tzload(name, sp)
271 const char * name;
272 struct state * const sp;
273 {
274 const char * p;
275 int i;
276 int fid;
277
278 /* XXX The following is from OpenBSD, and I'm not sure it is correct */
279 if (name != NULL && issetugid() != 0)
280 if ((name[0] == ':' && name[1] == '/') ||
281 name[0] == '/' || strchr(name, '.'))
282 name = NULL;
283 if (name == NULL && (name = TZDEFAULT) == NULL)
284 return -1;
285 {
286 int doaccess;
287 struct stat stab;
288 /*
289 ** Section 4.9.1 of the C standard says that
290 ** "FILENAME_MAX expands to an integral constant expression
291 ** that is the size needed for an array of char large enough
292 ** to hold the longest file name string that the implementation
293 ** guarantees can be opened."
294 */
295 char fullname[FILENAME_MAX + 1];
296
297 if (name[0] == ':')
298 ++name;
299 doaccess = name[0] == '/';
300 if (!doaccess) {
301 if ((p = TZDIR) == NULL)
302 return -1;
303 if ((strlen(p) + 1 + strlen(name) + 1) >= sizeof fullname)
304 return -1;
305 (void) strcpy(fullname, p);
306 (void) strcat(fullname, "/");
307 (void) strcat(fullname, name);
308 /*
309 ** Set doaccess if '.' (as in "../") shows up in name.
310 */
311 if (strchr(name, '.') != NULL)
312 doaccess = TRUE;
313 name = fullname;
314 }
315 if (doaccess && access(name, R_OK) != 0)
316 return -1;
317 if ((fid = _open(name, OPEN_MODE)) == -1)
318 return -1;
319 if ((_fstat(fid, &stab) < 0) || !S_ISREG(stab.st_mode)) {
320 _close(fid);
321 return -1;
322 }
323 }
324 {
325 struct tzhead * tzhp;
326 char buf[sizeof *sp + sizeof *tzhp];
327 int ttisstdcnt;
328 int ttisgmtcnt;
329
330 i = _read(fid, buf, sizeof buf);
331 if (_close(fid) != 0)
332 return -1;
333 p = buf;
334 p += (sizeof tzhp->tzh_magic) + (sizeof tzhp->tzh_reserved);
335 ttisstdcnt = (int) detzcode(p);
336 p += 4;
337 ttisgmtcnt = (int) detzcode(p);
338 p += 4;
339 sp->leapcnt = (int) detzcode(p);
340 p += 4;
341 sp->timecnt = (int) detzcode(p);
342 p += 4;
343 sp->typecnt = (int) detzcode(p);
344 p += 4;
345 sp->charcnt = (int) detzcode(p);
346 p += 4;
347 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS ||
348 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES ||
349 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES ||
350 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS ||
351 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) ||
352 (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0))
353 return -1;
354 if (i - (p - buf) < sp->timecnt * 4 + /* ats */
355 sp->timecnt + /* types */
356 sp->typecnt * (4 + 2) + /* ttinfos */
357 sp->charcnt + /* chars */
358 sp->leapcnt * (4 + 4) + /* lsinfos */
359 ttisstdcnt + /* ttisstds */
360 ttisgmtcnt) /* ttisgmts */
361 return -1;
362 for (i = 0; i < sp->timecnt; ++i) {
363 sp->ats[i] = detzcode(p);
364 p += 4;
365 }
366 for (i = 0; i < sp->timecnt; ++i) {
367 sp->types[i] = (unsigned char) *p++;
368 if (sp->types[i] >= sp->typecnt)
369 return -1;
370 }
371 for (i = 0; i < sp->typecnt; ++i) {
372 struct ttinfo * ttisp;
373
374 ttisp = &sp->ttis[i];
375 ttisp->tt_gmtoff = detzcode(p);
376 p += 4;
377 ttisp->tt_isdst = (unsigned char) *p++;
378 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1)
379 return -1;
380 ttisp->tt_abbrind = (unsigned char) *p++;
381 if (ttisp->tt_abbrind < 0 ||
382 ttisp->tt_abbrind > sp->charcnt)
383 return -1;
384 }
385 for (i = 0; i < sp->charcnt; ++i)
386 sp->chars[i] = *p++;
387 sp->chars[i] = '\0'; /* ensure '\0' at end */
388 for (i = 0; i < sp->leapcnt; ++i) {
389 struct lsinfo * lsisp;
390
391 lsisp = &sp->lsis[i];
392 lsisp->ls_trans = detzcode(p);
393 p += 4;
394 lsisp->ls_corr = detzcode(p);
395 p += 4;
396 }
397 for (i = 0; i < sp->typecnt; ++i) {
398 struct ttinfo * ttisp;
399
400 ttisp = &sp->ttis[i];
401 if (ttisstdcnt == 0)
402 ttisp->tt_ttisstd = FALSE;
403 else {
404 ttisp->tt_ttisstd = *p++;
405 if (ttisp->tt_ttisstd != TRUE &&
406 ttisp->tt_ttisstd != FALSE)
407 return -1;
408 }
409 }
410 for (i = 0; i < sp->typecnt; ++i) {
411 struct ttinfo * ttisp;
412
413 ttisp = &sp->ttis[i];
414 if (ttisgmtcnt == 0)
415 ttisp->tt_ttisgmt = FALSE;
416 else {
417 ttisp->tt_ttisgmt = *p++;
418 if (ttisp->tt_ttisgmt != TRUE &&
419 ttisp->tt_ttisgmt != FALSE)
420 return -1;
421 }
422 }
423 }
424 return 0;
425 }
426
427 static const int mon_lengths[2][MONSPERYEAR] = {
428 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
429 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }
430 };
431
432 static const int year_lengths[2] = {
433 DAYSPERNYEAR, DAYSPERLYEAR
434 };
435
436 /*
437 ** Given a pointer into a time zone string, scan until a character that is not
438 ** a valid character in a zone name is found. Return a pointer to that
439 ** character.
440 */
441
442 static const char *
443 getzname(strp)
444 const char * strp;
445 {
446 char c;
447
448 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' &&
449 c != '+')
450 ++strp;
451 return strp;
452 }
453
454 /*
455 ** Given a pointer into a time zone string, extract a number from that string.
456 ** Check that the number is within a specified range; if it is not, return
457 ** NULL.
458 ** Otherwise, return a pointer to the first character not part of the number.
459 */
460
461 static const char *
462 getnum(strp, nump, min, max)
463 const char * strp;
464 int * const nump;
465 const int min;
466 const int max;
467 {
468 char c;
469 int num;
470
471 if (strp == NULL || !is_digit(c = *strp))
472 return NULL;
473 num = 0;
474 do {
475 num = num * 10 + (c - '0');
476 if (num > max)
477 return NULL; /* illegal value */
478 c = *++strp;
479 } while (is_digit(c));
480 if (num < min)
481 return NULL; /* illegal value */
482 *nump = num;
483 return strp;
484 }
485
486 /*
487 ** Given a pointer into a time zone string, extract a number of seconds,
488 ** in hh[:mm[:ss]] form, from the string.
489 ** If any error occurs, return NULL.
490 ** Otherwise, return a pointer to the first character not part of the number
491 ** of seconds.
492 */
493
494 static const char *
495 getsecs(strp, secsp)
496 const char * strp;
497 long * const secsp;
498 {
499 int num;
500
501 /*
502 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like
503 ** "M10.4.6/26", which does not conform to Posix,
504 ** but which specifies the equivalent of
505 ** ``02:00 on the first Sunday on or after 23 Oct''.
506 */
507 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1);
508 if (strp == NULL)
509 return NULL;
510 *secsp = num * (long) SECSPERHOUR;
511 if (*strp == ':') {
512 ++strp;
513 strp = getnum(strp, &num, 0, MINSPERHOUR - 1);
514 if (strp == NULL)
515 return NULL;
516 *secsp += num * SECSPERMIN;
517 if (*strp == ':') {
518 ++strp;
519 /* `SECSPERMIN' allows for leap seconds. */
520 strp = getnum(strp, &num, 0, SECSPERMIN);
521 if (strp == NULL)
522 return NULL;
523 *secsp += num;
524 }
525 }
526 return strp;
527 }
528
529 /*
530 ** Given a pointer into a time zone string, extract an offset, in
531 ** [+-]hh[:mm[:ss]] form, from the string.
532 ** If any error occurs, return NULL.
533 ** Otherwise, return a pointer to the first character not part of the time.
534 */
535
536 static const char *
537 getoffset(strp, offsetp)
538 const char * strp;
539 long * const offsetp;
540 {
541 int neg = 0;
542
543 if (*strp == '-') {
544 neg = 1;
545 ++strp;
546 } else if (*strp == '+')
547 ++strp;
548 strp = getsecs(strp, offsetp);
549 if (strp == NULL)
550 return NULL; /* illegal time */
551 if (neg)
552 *offsetp = -*offsetp;
553 return strp;
554 }
555
556 /*
557 ** Given a pointer into a time zone string, extract a rule in the form
558 ** date[/time]. See POSIX section 8 for the format of "date" and "time".
559 ** If a valid rule is not found, return NULL.
560 ** Otherwise, return a pointer to the first character not part of the rule.
561 */
562
563 static const char *
564 getrule(strp, rulep)
565 const char * strp;
566 struct rule * const rulep;
567 {
568 if (*strp == 'J') {
569 /*
570 ** Julian day.
571 */
572 rulep->r_type = JULIAN_DAY;
573 ++strp;
574 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR);
575 } else if (*strp == 'M') {
576 /*
577 ** Month, week, day.
578 */
579 rulep->r_type = MONTH_NTH_DAY_OF_WEEK;
580 ++strp;
581 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR);
582 if (strp == NULL)
583 return NULL;
584 if (*strp++ != '.')
585 return NULL;
586 strp = getnum(strp, &rulep->r_week, 1, 5);
587 if (strp == NULL)
588 return NULL;
589 if (*strp++ != '.')
590 return NULL;
591 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1);
592 } else if (is_digit(*strp)) {
593 /*
594 ** Day of year.
595 */
596 rulep->r_type = DAY_OF_YEAR;
597 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1);
598 } else return NULL; /* invalid format */
599 if (strp == NULL)
600 return NULL;
601 if (*strp == '/') {
602 /*
603 ** Time specified.
604 */
605 ++strp;
606 strp = getsecs(strp, &rulep->r_time);
607 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */
608 return strp;
609 }
610
611 /*
612 ** Given the Epoch-relative time of January 1, 00:00:00 GMT, in a year, the
613 ** year, a rule, and the offset from GMT at the time that rule takes effect,
614 ** calculate the Epoch-relative time that rule takes effect.
615 */
616
617 static time_t
618 transtime(janfirst, year, rulep, offset)
619 const time_t janfirst;
620 const int year;
621 const struct rule * const rulep;
622 const long offset;
623 {
624 int leapyear;
625 time_t value;
626 int i;
627 int d, m1, yy0, yy1, yy2, dow;
628
629 INITIALIZE(value);
630 leapyear = isleap(year);
631 switch (rulep->r_type) {
632
633 case JULIAN_DAY:
634 /*
635 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap
636 ** years.
637 ** In non-leap years, or if the day number is 59 or less, just
638 ** add SECSPERDAY times the day number-1 to the time of
639 ** January 1, midnight, to get the day.
640 */
641 value = janfirst + (rulep->r_day - 1) * SECSPERDAY;
642 if (leapyear && rulep->r_day >= 60)
643 value += SECSPERDAY;
644 break;
645
646 case DAY_OF_YEAR:
647 /*
648 ** n - day of year.
649 ** Just add SECSPERDAY times the day number to the time of
650 ** January 1, midnight, to get the day.
651 */
652 value = janfirst + rulep->r_day * SECSPERDAY;
653 break;
654
655 case MONTH_NTH_DAY_OF_WEEK:
656 /*
657 ** Mm.n.d - nth "dth day" of month m.
658 */
659 value = janfirst;
660 for (i = 0; i < rulep->r_mon - 1; ++i)
661 value += mon_lengths[leapyear][i] * SECSPERDAY;
662
663 /*
664 ** Use Zeller's Congruence to get day-of-week of first day of
665 ** month.
666 */
667 m1 = (rulep->r_mon + 9) % 12 + 1;
668 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year;
669 yy1 = yy0 / 100;
670 yy2 = yy0 % 100;
671 dow = ((26 * m1 - 2) / 10 +
672 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7;
673 if (dow < 0)
674 dow += DAYSPERWEEK;
675
676 /*
677 ** "dow" is the day-of-week of the first day of the month. Get
678 ** the day-of-month (zero-origin) of the first "dow" day of the
679 ** month.
680 */
681 d = rulep->r_day - dow;
682 if (d < 0)
683 d += DAYSPERWEEK;
684 for (i = 1; i < rulep->r_week; ++i) {
685 if (d + DAYSPERWEEK >=
686 mon_lengths[leapyear][rulep->r_mon - 1])
687 break;
688 d += DAYSPERWEEK;
689 }
690
691 /*
692 ** "d" is the day-of-month (zero-origin) of the day we want.
693 */
694 value += d * SECSPERDAY;
695 break;
696 }
697
698 /*
699 ** "value" is the Epoch-relative time of 00:00:00 GMT on the day in
700 ** question. To get the Epoch-relative time of the specified local
701 ** time on that day, add the transition time and the current offset
702 ** from GMT.
703 */
704 return value + rulep->r_time + offset;
705 }
706
707 /*
708 ** Given a POSIX section 8-style TZ string, fill in the rule tables as
709 ** appropriate.
710 */
711
712 static int
713 tzparse(name, sp, lastditch)
714 const char * name;
715 struct state * const sp;
716 const int lastditch;
717 {
718 const char * stdname;
719 const char * dstname;
720 size_t stdlen;
721 size_t dstlen;
722 long stdoffset;
723 long dstoffset;
724 time_t * atp;
725 unsigned char * typep;
726 char * cp;
727 int load_result;
728
729 INITIALIZE(dstname);
730 stdname = name;
731 if (lastditch) {
732 stdlen = strlen(name); /* length of standard zone name */
733 name += stdlen;
734 if (stdlen >= sizeof sp->chars)
735 stdlen = (sizeof sp->chars) - 1;
736 stdoffset = 0;
737 } else {
738 name = getzname(name);
739 stdlen = name - stdname;
740 if (stdlen < 3)
741 return -1;
742 if (*name == '\0')
743 return -1; /* was "stdoffset = 0;" */
744 else {
745 name = getoffset(name, &stdoffset);
746 if (name == NULL)
747 return -1;
748 }
749 }
750 load_result = tzload(TZDEFRULES, sp);
751 if (load_result != 0)
752 sp->leapcnt = 0; /* so, we're off a little */
753 if (*name != '\0') {
754 dstname = name;
755 name = getzname(name);
756 dstlen = name - dstname; /* length of DST zone name */
757 if (dstlen < 3)
758 return -1;
759 if (*name != '\0' && *name != ',' && *name != ';') {
760 name = getoffset(name, &dstoffset);
761 if (name == NULL)
762 return -1;
763 } else dstoffset = stdoffset - SECSPERHOUR;
764 if (*name == ',' || *name == ';') {
765 struct rule start;
766 struct rule end;
767 int year;
768 time_t janfirst;
769 time_t starttime;
770 time_t endtime;
771
772 ++name;
773 if ((name = getrule(name, &start)) == NULL)
774 return -1;
775 if (*name++ != ',')
776 return -1;
777 if ((name = getrule(name, &end)) == NULL)
778 return -1;
779 if (*name != '\0')
780 return -1;
781 sp->typecnt = 2; /* standard time and DST */
782 /*
783 ** Two transitions per year, from EPOCH_YEAR to 2037.
784 */
785 sp->timecnt = 2 * (2037 - EPOCH_YEAR + 1);
786 if (sp->timecnt > TZ_MAX_TIMES)
787 return -1;
788 sp->ttis[0].tt_gmtoff = -dstoffset;
789 sp->ttis[0].tt_isdst = 1;
790 sp->ttis[0].tt_abbrind = stdlen + 1;
791 sp->ttis[1].tt_gmtoff = -stdoffset;
792 sp->ttis[1].tt_isdst = 0;
793 sp->ttis[1].tt_abbrind = 0;
794 atp = sp->ats;
795 typep = sp->types;
796 janfirst = 0;
797 for (year = EPOCH_YEAR; year <= 2037; ++year) {
798 starttime = transtime(janfirst, year, &start,
799 stdoffset);
800 endtime = transtime(janfirst, year, &end,
801 dstoffset);
802 if (starttime > endtime) {
803 *atp++ = endtime;
804 *typep++ = 1; /* DST ends */
805 *atp++ = starttime;
806 *typep++ = 0; /* DST begins */
807 } else {
808 *atp++ = starttime;
809 *typep++ = 0; /* DST begins */
810 *atp++ = endtime;
811 *typep++ = 1; /* DST ends */
812 }
813 janfirst += year_lengths[isleap(year)] *
814 SECSPERDAY;
815 }
816 } else {
817 long theirstdoffset;
818 long theirdstoffset;
819 long theiroffset;
820 int isdst;
821 int i;
822 int j;
823
824 if (*name != '\0')
825 return -1;
826 if (load_result != 0)
827 return -1;
828 /*
829 ** Initial values of theirstdoffset and theirdstoffset.
830 */
831 theirstdoffset = 0;
832 for (i = 0; i < sp->timecnt; ++i) {
833 j = sp->types[i];
834 if (!sp->ttis[j].tt_isdst) {
835 theirstdoffset =
836 -sp->ttis[j].tt_gmtoff;
837 break;
838 }
839 }
840 theirdstoffset = 0;
841 for (i = 0; i < sp->timecnt; ++i) {
842 j = sp->types[i];
843 if (sp->ttis[j].tt_isdst) {
844 theirdstoffset =
845 -sp->ttis[j].tt_gmtoff;
846 break;
847 }
848 }
849 /*
850 ** Initially we're assumed to be in standard time.
851 */
852 isdst = FALSE;
853 theiroffset = theirstdoffset;
854 /*
855 ** Now juggle transition times and types
856 ** tracking offsets as you do.
857 */
858 for (i = 0; i < sp->timecnt; ++i) {
859 j = sp->types[i];
860 sp->types[i] = sp->ttis[j].tt_isdst;
861 if (sp->ttis[j].tt_ttisgmt) {
862 /* No adjustment to transition time */
863 } else {
864 /*
865 ** If summer time is in effect, and the
866 ** transition time was not specified as
867 ** standard time, add the summer time
868 ** offset to the transition time;
869 ** otherwise, add the standard time
870 ** offset to the transition time.
871 */
872 /*
873 ** Transitions from DST to DDST
874 ** will effectively disappear since
875 ** POSIX provides for only one DST
876 ** offset.
877 */
878 if (isdst && !sp->ttis[j].tt_ttisstd) {
879 sp->ats[i] += dstoffset -
880 theirdstoffset;
881 } else {
882 sp->ats[i] += stdoffset -
883 theirstdoffset;
884 }
885 }
886 theiroffset = -sp->ttis[j].tt_gmtoff;
887 if (sp->ttis[j].tt_isdst)
888 theirdstoffset = theiroffset;
889 else theirstdoffset = theiroffset;
890 }
891 /*
892 ** Finally, fill in ttis.
893 ** ttisstd and ttisgmt need not be handled.
894 */
895 sp->ttis[0].tt_gmtoff = -stdoffset;
896 sp->ttis[0].tt_isdst = FALSE;
897 sp->ttis[0].tt_abbrind = 0;
898 sp->ttis[1].tt_gmtoff = -dstoffset;
899 sp->ttis[1].tt_isdst = TRUE;
900 sp->ttis[1].tt_abbrind = stdlen + 1;
901 }
902 } else {
903 dstlen = 0;
904 sp->typecnt = 1; /* only standard time */
905 sp->timecnt = 0;
906 sp->ttis[0].tt_gmtoff = -stdoffset;
907 sp->ttis[0].tt_isdst = 0;
908 sp->ttis[0].tt_abbrind = 0;
909 }
910 sp->charcnt = stdlen + 1;
911 if (dstlen != 0)
912 sp->charcnt += dstlen + 1;
913 if (sp->charcnt > sizeof sp->chars)
914 return -1;
915 cp = sp->chars;
916 (void) strncpy(cp, stdname, stdlen);
917 cp += stdlen;
918 *cp++ = '\0';
919 if (dstlen != 0) {
920 (void) strncpy(cp, dstname, dstlen);
921 *(cp + dstlen) = '\0';
922 }
923 return 0;
924 }
925
926 static void
927 gmtload(sp)
928 struct state * const sp;
929 {
930 if (tzload(gmt, sp) != 0)
931 (void) tzparse(gmt, sp, TRUE);
932 }
933
934 static void
935 tzsetwall_basic(void)
936 {
937 if (lcl_is_set < 0)
938 return;
939 lcl_is_set = -1;
940
941 #ifdef ALL_STATE
942 if (lclptr == NULL) {
943 lclptr = (struct state *) malloc(sizeof *lclptr);
944 if (lclptr == NULL) {
945 settzname(); /* all we can do */
946 return;
947 }
948 }
949 #endif /* defined ALL_STATE */
950 if (tzload((char *) NULL, lclptr) != 0)
951 gmtload(lclptr);
952 settzname();
953 }
954
955 void
956 tzsetwall(void)
957 {
958 _MUTEX_LOCK(&lcl_mutex);
959 tzsetwall_basic();
960 _MUTEX_UNLOCK(&lcl_mutex);
961 }
962
963 static void
964 tzset_basic(void)
965 {
966 const char * name;
967
968 name = getenv("TZ");
969 if (name == NULL) {
970 tzsetwall_basic();
971 return;
972 }
973
974 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0)
975 return;
976 lcl_is_set = (strlen(name) < sizeof(lcl_TZname));
977 if (lcl_is_set)
978 (void) strcpy(lcl_TZname, name);
979
980 #ifdef ALL_STATE
981 if (lclptr == NULL) {
982 lclptr = (struct state *) malloc(sizeof *lclptr);
983 if (lclptr == NULL) {
984 settzname(); /* all we can do */
985 return;
986 }
987 }
988 #endif /* defined ALL_STATE */
989 if (*name == '\0') {
990 /*
991 ** User wants it fast rather than right.
992 */
993 lclptr->leapcnt = 0; /* so, we're off a little */
994 lclptr->timecnt = 0;
995 lclptr->ttis[0].tt_gmtoff = 0;
996 lclptr->ttis[0].tt_abbrind = 0;
997 (void) strcpy(lclptr->chars, gmt);
998 } else if (tzload(name, lclptr) != 0)
999 if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0)
1000 (void) gmtload(lclptr);
1001 settzname();
1002 }
1003
1004 void
1005 tzset(void)
1006 {
1007 _MUTEX_LOCK(&lcl_mutex);
1008 tzset_basic();
1009 _MUTEX_UNLOCK(&lcl_mutex);
1010 }
1011
1012 /*
1013 ** The easy way to behave "as if no library function calls" localtime
1014 ** is to not call it--so we drop its guts into "localsub", which can be
1015 ** freely called. (And no, the PANS doesn't require the above behavior--
1016 ** but it *is* desirable.)
1017 **
1018 ** The unused offset argument is for the benefit of mktime variants.
1019 */
1020
1021 /*ARGSUSED*/
1022 static void
1023 localsub(timep, offset, tmp)
1024 const time_t * const timep;
1025 const long offset;
1026 struct tm * const tmp;
1027 {
1028 struct state * sp;
1029 const struct ttinfo * ttisp;
1030 int i;
1031 const time_t t = *timep;
1032
1033 sp = lclptr;
1034 #ifdef ALL_STATE
1035 if (sp == NULL) {
1036 gmtsub(timep, offset, tmp);
1037 return;
1038 }
1039 #endif /* defined ALL_STATE */
1040 if (sp->timecnt == 0 || t < sp->ats[0]) {
1041 i = 0;
1042 while (sp->ttis[i].tt_isdst)
1043 if (++i >= sp->typecnt) {
1044 i = 0;
1045 break;
1046 }
1047 } else {
1048 for (i = 1; i < sp->timecnt; ++i)
1049 if (t < sp->ats[i])
1050 break;
1051 i = sp->types[i - 1];
1052 }
1053 ttisp = &sp->ttis[i];
1054 /*
1055 ** To get (wrong) behavior that's compatible with System V Release 2.0
1056 ** you'd replace the statement below with
1057 ** t += ttisp->tt_gmtoff;
1058 ** timesub(&t, 0L, sp, tmp);
1059 */
1060 timesub(&t, ttisp->tt_gmtoff, sp, tmp);
1061 tmp->tm_isdst = ttisp->tt_isdst;
1062 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind];
1063 #ifdef TM_ZONE
1064 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind];
1065 #endif /* defined TM_ZONE */
1066 }
1067
1068 struct tm *
1069 localtime_r(timep, p_tm)
1070 const time_t * const timep;
1071 struct tm *p_tm;
1072 {
1073 _MUTEX_LOCK(&lcl_mutex);
1074 tzset_basic();
1075 localsub(timep, 0L, p_tm);
1076 _MUTEX_UNLOCK(&lcl_mutex);
1077 return(p_tm);
1078 }
1079
1080 struct tm *
1081 localtime(timep)
1082 const time_t * const timep;
1083 {
1084 static pthread_mutex_t localtime_mutex = PTHREAD_MUTEX_INITIALIZER;
1085 static pthread_key_t localtime_key = -1;
1086 struct tm *p_tm;
1087
1088 if (__isthreaded != 0) {
1089 _pthread_mutex_lock(&localtime_mutex);
1090 if (localtime_key < 0) {
1091 if (_pthread_key_create(&localtime_key, free) < 0) {
1092 _pthread_mutex_unlock(&localtime_mutex);
1093 return(NULL);
1094 }
1095 }
1096 _pthread_mutex_unlock(&localtime_mutex);
1097 p_tm = _pthread_getspecific(localtime_key);
1098 if (p_tm == NULL) {
1099 if ((p_tm = (struct tm *)malloc(sizeof(struct tm)))
1100 == NULL)
1101 return(NULL);
1102 _pthread_setspecific(localtime_key, p_tm);
1103 }
1104 _pthread_mutex_lock(&lcl_mutex);
1105 tzset_basic();
1106 localsub(timep, 0L, p_tm);
1107 _pthread_mutex_unlock(&lcl_mutex);
1108 return(p_tm);
1109 } else {
1110 tzset_basic();
1111 localsub(timep, 0L, &tm);
1112 return(&tm);
1113 }
1114 }
1115
1116 /*
1117 ** gmtsub is to gmtime as localsub is to localtime.
1118 */
1119
1120 static void
1121 gmtsub(timep, offset, tmp)
1122 const time_t * const timep;
1123 const long offset;
1124 struct tm * const tmp;
1125 {
1126 _MUTEX_LOCK(&gmt_mutex);
1127 if (!gmt_is_set) {
1128 gmt_is_set = TRUE;
1129 #ifdef ALL_STATE
1130 gmtptr = (struct state *) malloc(sizeof *gmtptr);
1131 if (gmtptr != NULL)
1132 #endif /* defined ALL_STATE */
1133 gmtload(gmtptr);
1134 }
1135 _MUTEX_UNLOCK(&gmt_mutex);
1136 timesub(timep, offset, gmtptr, tmp);
1137 #ifdef TM_ZONE
1138 /*
1139 ** Could get fancy here and deliver something such as
1140 ** "GMT+xxxx" or "GMT-xxxx" if offset is non-zero,
1141 ** but this is no time for a treasure hunt.
1142 */
1143 if (offset != 0)
1144 tmp->TM_ZONE = wildabbr;
1145 else {
1146 #ifdef ALL_STATE
1147 if (gmtptr == NULL)
1148 tmp->TM_ZONE = gmt;
1149 else tmp->TM_ZONE = gmtptr->chars;
1150 #endif /* defined ALL_STATE */
1151 #ifndef ALL_STATE
1152 tmp->TM_ZONE = gmtptr->chars;
1153 #endif /* State Farm */
1154 }
1155 #endif /* defined TM_ZONE */
1156 }
1157
1158 struct tm *
1159 gmtime(timep)
1160 const time_t * const timep;
1161 {
1162 static pthread_mutex_t gmtime_mutex = PTHREAD_MUTEX_INITIALIZER;
1163 static pthread_key_t gmtime_key = -1;
1164 struct tm *p_tm;
1165
1166 if (__isthreaded != 0) {
1167 _pthread_mutex_lock(&gmtime_mutex);
1168 if (gmtime_key < 0) {
1169 if (_pthread_key_create(&gmtime_key, free) < 0) {
1170 _pthread_mutex_unlock(&gmtime_mutex);
1171 return(NULL);
1172 }
1173 }
1174 _pthread_mutex_unlock(&gmtime_mutex);
1175 /*
1176 * Changed to follow POSIX.1 threads standard, which
1177 * is what BSD currently has.
1178 */
1179 if ((p_tm = _pthread_getspecific(gmtime_key)) == NULL) {
1180 if ((p_tm = (struct tm *)malloc(sizeof(struct tm)))
1181 == NULL) {
1182 return(NULL);
1183 }
1184 _pthread_setspecific(gmtime_key, p_tm);
1185 }
1186 gmtsub(timep, 0L, p_tm);
1187 return(p_tm);
1188 }
1189 else {
1190 gmtsub(timep, 0L, &tm);
1191 return(&tm);
1192 }
1193 }
1194
1195 struct tm *
1196 gmtime_r(const time_t * timep, struct tm * tm)
1197 {
1198 gmtsub(timep, 0L, tm);
1199 return(tm);
1200 }
1201
1202 #ifdef STD_INSPIRED
1203
1204 struct tm *
1205 offtime(timep, offset)
1206 const time_t * const timep;
1207 const long offset;
1208 {
1209 gmtsub(timep, offset, &tm);
1210 return &tm;
1211 }
1212
1213 #endif /* defined STD_INSPIRED */
1214
1215 static void
1216 timesub(timep, offset, sp, tmp)
1217 const time_t * const timep;
1218 const long offset;
1219 const struct state * const sp;
1220 struct tm * const tmp;
1221 {
1222 const struct lsinfo * lp;
1223 long days;
1224 long rem;
1225 long y;
1226 int yleap;
1227 const int * ip;
1228 long corr;
1229 int hit;
1230 int i;
1231
1232 corr = 0;
1233 hit = 0;
1234 #ifdef ALL_STATE
1235 i = (sp == NULL) ? 0 : sp->leapcnt;
1236 #endif /* defined ALL_STATE */
1237 #ifndef ALL_STATE
1238 i = sp->leapcnt;
1239 #endif /* State Farm */
1240 while (--i >= 0) {
1241 lp = &sp->lsis[i];
1242 if (*timep >= lp->ls_trans) {
1243 if (*timep == lp->ls_trans) {
1244 hit = ((i == 0 && lp->ls_corr > 0) ||
1245 lp->ls_corr > sp->lsis[i - 1].ls_corr);
1246 if (hit)
1247 while (i > 0 &&
1248 sp->lsis[i].ls_trans ==
1249 sp->lsis[i - 1].ls_trans + 1 &&
1250 sp->lsis[i].ls_corr ==
1251 sp->lsis[i - 1].ls_corr + 1) {
1252 ++hit;
1253 --i;
1254 }
1255 }
1256 corr = lp->ls_corr;
1257 break;
1258 }
1259 }
1260 days = *timep / SECSPERDAY;
1261 rem = *timep % SECSPERDAY;
1262 #ifdef mc68k
1263 if (*timep == 0x80000000) {
1264 /*
1265 ** A 3B1 muffs the division on the most negative number.
1266 */
1267 days = -24855;
1268 rem = -11648;
1269 }
1270 #endif /* defined mc68k */
1271 rem += (offset - corr);
1272 while (rem < 0) {
1273 rem += SECSPERDAY;
1274 --days;
1275 }
1276 while (rem >= SECSPERDAY) {
1277 rem -= SECSPERDAY;
1278 ++days;
1279 }
1280 tmp->tm_hour = (int) (rem / SECSPERHOUR);
1281 rem = rem % SECSPERHOUR;
1282 tmp->tm_min = (int) (rem / SECSPERMIN);
1283 /*
1284 ** A positive leap second requires a special
1285 ** representation. This uses "... ??:59:60" et seq.
1286 */
1287 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit;
1288 tmp->tm_wday = (int) ((EPOCH_WDAY + days) % DAYSPERWEEK);
1289 if (tmp->tm_wday < 0)
1290 tmp->tm_wday += DAYSPERWEEK;
1291 y = EPOCH_YEAR;
1292 #define LEAPS_THRU_END_OF(y) ((y) / 4 - (y) / 100 + (y) / 400)
1293 while (days < 0 || days >= (long) year_lengths[yleap = isleap(y)]) {
1294 long newy;
1295
1296 newy = y + days / DAYSPERNYEAR;
1297 if (days < 0)
1298 --newy;
1299 days -= (newy - y) * DAYSPERNYEAR +
1300 LEAPS_THRU_END_OF(newy - 1) -
1301 LEAPS_THRU_END_OF(y - 1);
1302 y = newy;
1303 }
1304 tmp->tm_year = y - TM_YEAR_BASE;
1305 tmp->tm_yday = (int) days;
1306 ip = mon_lengths[yleap];
1307 for (tmp->tm_mon = 0; days >= (long) ip[tmp->tm_mon]; ++(tmp->tm_mon))
1308 days = days - (long) ip[tmp->tm_mon];
1309 tmp->tm_mday = (int) (days + 1);
1310 tmp->tm_isdst = 0;
1311 #ifdef TM_GMTOFF
1312 tmp->TM_GMTOFF = offset;
1313 #endif /* defined TM_GMTOFF */
1314 }
1315
1316 char *
1317 ctime(timep)
1318 const time_t * const timep;
1319 {
1320 /*
1321 ** Section 4.12.3.2 of X3.159-1989 requires that
1322 ** The ctime funciton converts the calendar time pointed to by timer
1323 ** to local time in the form of a string. It is equivalent to
1324 ** asctime(localtime(timer))
1325 */
1326 return asctime(localtime(timep));
1327 }
1328
1329 char *
1330 ctime_r(timep, buf)
1331 const time_t * const timep;
1332 char *buf;
1333 {
1334 struct tm tm;
1335 return asctime_r(localtime_r(timep, &tm), buf);
1336 }
1337
1338 /*
1339 ** Adapted from code provided by Robert Elz, who writes:
1340 ** The "best" way to do mktime I think is based on an idea of Bob
1341 ** Kridle's (so its said...) from a long time ago.
1342 ** [kridle@xinet.com as of 1996-01-16.]
1343 ** It does a binary search of the time_t space. Since time_t's are
1344 ** just 32 bits, its a max of 32 iterations (even at 64 bits it
1345 ** would still be very reasonable).
1346 */
1347
1348 #ifndef WRONG
1349 #define WRONG (-1)
1350 #endif /* !defined WRONG */
1351
1352 /*
1353 ** Simplified normalize logic courtesy Paul Eggert (eggert@twinsun.com).
1354 */
1355
1356 static int
1357 increment_overflow(number, delta)
1358 int * number;
1359 int delta;
1360 {
1361 int number0;
1362
1363 number0 = *number;
1364 *number += delta;
1365 return (*number < number0) != (delta < 0);
1366 }
1367
1368 static int
1369 normalize_overflow(tensptr, unitsptr, base)
1370 int * const tensptr;
1371 int * const unitsptr;
1372 const int base;
1373 {
1374 int tensdelta;
1375
1376 tensdelta = (*unitsptr >= 0) ?
1377 (*unitsptr / base) :
1378 (-1 - (-1 - *unitsptr) / base);
1379 *unitsptr -= tensdelta * base;
1380 return increment_overflow(tensptr, tensdelta);
1381 }
1382
1383 static int
1384 tmcomp(atmp, btmp)
1385 const struct tm * const atmp;
1386 const struct tm * const btmp;
1387 {
1388 int result;
1389
1390 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 &&
1391 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 &&
1392 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 &&
1393 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 &&
1394 (result = (atmp->tm_min - btmp->tm_min)) == 0)
1395 result = atmp->tm_sec - btmp->tm_sec;
1396 return result;
1397 }
1398
1399 static time_t
1400 time2(tmp, funcp, offset, okayp)
1401 struct tm * const tmp;
1402 void (* const funcp)(const time_t*, long, struct tm*);
1403 const long offset;
1404 int * const okayp;
1405 {
1406 const struct state * sp;
1407 int dir;
1408 int bits;
1409 int i, j ;
1410 int saved_seconds;
1411 time_t newt;
1412 time_t t;
1413 struct tm yourtm, mytm;
1414
1415 *okayp = FALSE;
1416 yourtm = *tmp;
1417 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR))
1418 return WRONG;
1419 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY))
1420 return WRONG;
1421 if (normalize_overflow(&yourtm.tm_year, &yourtm.tm_mon, MONSPERYEAR))
1422 return WRONG;
1423 /*
1424 ** Turn yourtm.tm_year into an actual year number for now.
1425 ** It is converted back to an offset from TM_YEAR_BASE later.
1426 */
1427 if (increment_overflow(&yourtm.tm_year, TM_YEAR_BASE))
1428 return WRONG;
1429 while (yourtm.tm_mday <= 0) {
1430 if (increment_overflow(&yourtm.tm_year, -1))
1431 return WRONG;
1432 i = yourtm.tm_year + (1 < yourtm.tm_mon);
1433 yourtm.tm_mday += year_lengths[isleap(i)];
1434 }
1435 while (yourtm.tm_mday > DAYSPERLYEAR) {
1436 i = yourtm.tm_year + (1 < yourtm.tm_mon);
1437 yourtm.tm_mday -= year_lengths[isleap(i)];
1438 if (increment_overflow(&yourtm.tm_year, 1))
1439 return WRONG;
1440 }
1441 for ( ; ; ) {
1442 i = mon_lengths[isleap(yourtm.tm_year)][yourtm.tm_mon];
1443 if (yourtm.tm_mday <= i)
1444 break;
1445 yourtm.tm_mday -= i;
1446 if (++yourtm.tm_mon >= MONSPERYEAR) {
1447 yourtm.tm_mon = 0;
1448 if (increment_overflow(&yourtm.tm_year, 1))
1449 return WRONG;
1450 }
1451 }
1452 if (increment_overflow(&yourtm.tm_year, -TM_YEAR_BASE))
1453 return WRONG;
1454 if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN)
1455 saved_seconds = 0;
1456 else if (yourtm.tm_year + TM_YEAR_BASE < EPOCH_YEAR) {
1457 /*
1458 ** We can't set tm_sec to 0, because that might push the
1459 ** time below the minimum representable time.
1460 ** Set tm_sec to 59 instead.
1461 ** This assumes that the minimum representable time is
1462 ** not in the same minute that a leap second was deleted from,
1463 ** which is a safer assumption than using 58 would be.
1464 */
1465 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN))
1466 return WRONG;
1467 saved_seconds = yourtm.tm_sec;
1468 yourtm.tm_sec = SECSPERMIN - 1;
1469 } else {
1470 saved_seconds = yourtm.tm_sec;
1471 yourtm.tm_sec = 0;
1472 }
1473 /*
1474 ** Divide the search space in half
1475 ** (this works whether time_t is signed or unsigned).
1476 */
1477 bits = TYPE_BIT(time_t) - 1;
1478 /*
1479 ** If we have more than this, we will overflow tm_year for tmcomp().
1480 ** We should really return an error if we cannot represent it.
1481 */
1482 if (bits > 56)
1483 bits = 56;
1484 /*
1485 ** If time_t is signed, then 0 is just above the median,
1486 ** assuming two's complement arithmetic.
1487 ** If time_t is unsigned, then (1 << bits) is just above the median.
1488 */
1489 t = TYPE_SIGNED(time_t) ? 0 : (((time_t) 1) << bits);
1490 for ( ; ; ) {
1491 (*funcp)(&t, offset, &mytm);
1492 dir = tmcomp(&mytm, &yourtm);
1493 if (dir != 0) {
1494 if (bits-- < 0)
1495 return WRONG;
1496 if (bits < 0)
1497 --t; /* may be needed if new t is minimal */
1498 else if (dir > 0)
1499 t -= ((time_t) 1) << bits;
1500 else t += ((time_t) 1) << bits;
1501 continue;
1502 }
1503 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst)
1504 break;
1505 /*
1506 ** Right time, wrong type.
1507 ** Hunt for right time, right type.
1508 ** It's okay to guess wrong since the guess
1509 ** gets checked.
1510 */
1511 /*
1512 ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's.
1513 */
1514 sp = (const struct state *)
1515 (((void *) funcp == (void *) localsub) ?
1516 lclptr : gmtptr);
1517 #ifdef ALL_STATE
1518 if (sp == NULL)
1519 return WRONG;
1520 #endif /* defined ALL_STATE */
1521 for (i = sp->typecnt - 1; i >= 0; --i) {
1522 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst)
1523 continue;
1524 for (j = sp->typecnt - 1; j >= 0; --j) {
1525 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst)
1526 continue;
1527 newt = t + sp->ttis[j].tt_gmtoff -
1528 sp->ttis[i].tt_gmtoff;
1529 (*funcp)(&newt, offset, &mytm);
1530 if (tmcomp(&mytm, &yourtm) != 0)
1531 continue;
1532 if (mytm.tm_isdst != yourtm.tm_isdst)
1533 continue;
1534 /*
1535 ** We have a match.
1536 */
1537 t = newt;
1538 goto label;
1539 }
1540 }
1541 return WRONG;
1542 }
1543 label:
1544 newt = t + saved_seconds;
1545 if ((newt < t) != (saved_seconds < 0))
1546 return WRONG;
1547 t = newt;
1548 (*funcp)(&t, offset, tmp);
1549 *okayp = TRUE;
1550 return t;
1551 }
1552
1553 static time_t
1554 time1(tmp, funcp, offset)
1555 struct tm * const tmp;
1556 void (* const funcp)(const time_t *, long, struct tm *);
1557 const long offset;
1558 {
1559 time_t t;
1560 const struct state * sp;
1561 int samei, otheri;
1562 int okay;
1563
1564 if (tmp->tm_isdst > 1)
1565 tmp->tm_isdst = 1;
1566 t = time2(tmp, funcp, offset, &okay);
1567 #ifdef PCTS
1568 /*
1569 ** PCTS code courtesy Grant Sullivan (grant@osf.org).
1570 */
1571 if (okay)
1572 return t;
1573 if (tmp->tm_isdst < 0)
1574 tmp->tm_isdst = 0; /* reset to std and try again */
1575 #endif /* defined PCTS */
1576 #ifndef PCTS
1577 if (okay || tmp->tm_isdst < 0)
1578 return t;
1579 #endif /* !defined PCTS */
1580 /*
1581 ** We're supposed to assume that somebody took a time of one type
1582 ** and did some math on it that yielded a "struct tm" that's bad.
1583 ** We try to divine the type they started from and adjust to the
1584 ** type they need.
1585 */
1586 /*
1587 ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's.
1588 */
1589 sp = (const struct state *) (((void *) funcp == (void *) localsub) ?
1590 lclptr : gmtptr);
1591 #ifdef ALL_STATE
1592 if (sp == NULL)
1593 return WRONG;
1594 #endif /* defined ALL_STATE */
1595 for (samei = sp->typecnt - 1; samei >= 0; --samei) {
1596 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst)
1597 continue;
1598 for (otheri = sp->typecnt - 1; otheri >= 0; --otheri) {
1599 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst)
1600 continue;
1601 tmp->tm_sec += sp->ttis[otheri].tt_gmtoff -
1602 sp->ttis[samei].tt_gmtoff;
1603 tmp->tm_isdst = !tmp->tm_isdst;
1604 t = time2(tmp, funcp, offset, &okay);
1605 if (okay)
1606 return t;
1607 tmp->tm_sec -= sp->ttis[otheri].tt_gmtoff -
1608 sp->ttis[samei].tt_gmtoff;
1609 tmp->tm_isdst = !tmp->tm_isdst;
1610 }
1611 }
1612 return WRONG;
1613 }
1614
1615 time_t
1616 mktime(tmp)
1617 struct tm * const tmp;
1618 {
1619 time_t mktime_return_value;
1620 _MUTEX_LOCK(&lcl_mutex);
1621 tzset_basic();
1622 mktime_return_value = time1(tmp, localsub, 0L);
1623 _MUTEX_UNLOCK(&lcl_mutex);
1624 return(mktime_return_value);
1625 }
1626
1627 #ifdef STD_INSPIRED
1628
1629 time_t
1630 timelocal(tmp)
1631 struct tm * const tmp;
1632 {
1633 tmp->tm_isdst = -1; /* in case it wasn't initialized */
1634 return mktime(tmp);
1635 }
1636
1637 time_t
1638 timegm(tmp)
1639 struct tm * const tmp;
1640 {
1641 tmp->tm_isdst = 0;
1642 return time1(tmp, gmtsub, 0L);
1643 }
1644
1645 time_t
1646 timeoff(tmp, offset)
1647 struct tm * const tmp;
1648 const long offset;
1649 {
1650 tmp->tm_isdst = 0;
1651 return time1(tmp, gmtsub, offset);
1652 }
1653
1654 #endif /* defined STD_INSPIRED */
1655
1656 #ifdef CMUCS
1657
1658 /*
1659 ** The following is supplied for compatibility with
1660 ** previous versions of the CMUCS runtime library.
1661 */
1662
1663 long
1664 gtime(tmp)
1665 struct tm * const tmp;
1666 {
1667 const time_t t = mktime(tmp);
1668
1669 if (t == WRONG)
1670 return -1;
1671 return t;
1672 }
1673
1674 #endif /* defined CMUCS */
1675
1676 /*
1677 ** XXX--is the below the right way to conditionalize??
1678 */
1679
1680 #ifdef STD_INSPIRED
1681
1682 /*
1683 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599
1684 ** shall correspond to "Wed Dec 31 23:59:59 GMT 1986", which
1685 ** is not the case if we are accounting for leap seconds.
1686 ** So, we provide the following conversion routines for use
1687 ** when exchanging timestamps with POSIX conforming systems.
1688 */
1689
1690 static long
1691 leapcorr(timep)
1692 time_t * timep;
1693 {
1694 struct state * sp;
1695 struct lsinfo * lp;
1696 int i;
1697
1698 sp = lclptr;
1699 i = sp->leapcnt;
1700 while (--i >= 0) {
1701 lp = &sp->lsis[i];
1702 if (*timep >= lp->ls_trans)
1703 return lp->ls_corr;
1704 }
1705 return 0;
1706 }
1707
1708 time_t
1709 time2posix(t)
1710 time_t t;
1711 {
1712 tzset();
1713 return t - leapcorr(&t);
1714 }
1715
1716 time_t
1717 posix2time(t)
1718 time_t t;
1719 {
1720 time_t x;
1721 time_t y;
1722
1723 tzset();
1724 /*
1725 ** For a positive leap second hit, the result
1726 ** is not unique. For a negative leap second
1727 ** hit, the corresponding time doesn't exist,
1728 ** so we return an adjacent second.
1729 */
1730 x = t + leapcorr(&t);
1731 y = x - leapcorr(&x);
1732 if (y < t) {
1733 do {
1734 x++;
1735 y = x - leapcorr(&x);
1736 } while (y < t);
1737 if (t != y)
1738 return x - 1;
1739 } else if (y > t) {
1740 do {
1741 --x;
1742 y = x - leapcorr(&x);
1743 } while (y > t);
1744 if (t != y)
1745 return x + 1;
1746 }
1747 return x;
1748 }
1749
1750 #endif /* defined STD_INSPIRED */
mirror of libc