localtime.c revision 1.34
1/* $NetBSD: localtime.c,v 1.34 2003/10/29 20:43:27 kleink Exp $ */ 2 3/* 4** This file is in the public domain, so clarified as of 5** 1996-06-05 by Arthur David Olson (arthur_david_olson@nih.gov). 6*/ 7 8#include <sys/cdefs.h> 9#if defined(LIBC_SCCS) && !defined(lint) 10#if 0 11static char elsieid[] = "@(#)localtime.c 7.76"; 12#else 13__RCSID("$NetBSD: localtime.c,v 1.34 2003/10/29 20:43:27 kleink Exp $"); 14#endif 15#endif /* LIBC_SCCS and not lint */ 16 17/* 18** Leap second handling from Bradley White (bww@k.gp.cs.cmu.edu). 19** POSIX-style TZ environment variable handling from Guy Harris 20** (guy@auspex.com). 21*/ 22 23/*LINTLIBRARY*/ 24 25#include "namespace.h" 26#include "private.h" 27#include "tzfile.h" 28#include "fcntl.h" 29#include "reentrant.h" 30 31#ifdef __weak_alias 32__weak_alias(ctime_r,_ctime_r) 33__weak_alias(daylight,_daylight) 34__weak_alias(gmtime_r,_gmtime_r) 35__weak_alias(localtime_r,_localtime_r) 36__weak_alias(offtime,_offtime) 37__weak_alias(posix2time,_posix2time) 38__weak_alias(time2posix,_time2posix) 39__weak_alias(timegm,_timegm) 40__weak_alias(timelocal,_timelocal) 41__weak_alias(timeoff,_timeoff) 42__weak_alias(tzname,_tzname) 43__weak_alias(tzset,_tzset) 44__weak_alias(tzsetwall,_tzsetwall) 45#endif 46 47/* 48** SunOS 4.1.1 headers lack O_BINARY. 49*/ 50 51#ifdef O_BINARY 52#define OPEN_MODE (O_RDONLY | O_BINARY) 53#endif /* defined O_BINARY */ 54#ifndef O_BINARY 55#define OPEN_MODE O_RDONLY 56#endif /* !defined O_BINARY */ 57 58#ifndef WILDABBR 59/* 60** Someone might make incorrect use of a time zone abbreviation: 61** 1. They might reference tzname[0] before calling tzset (explicitly 62** or implicitly). 63** 2. They might reference tzname[1] before calling tzset (explicitly 64** or implicitly). 65** 3. They might reference tzname[1] after setting to a time zone 66** in which Daylight Saving Time is never observed. 67** 4. They might reference tzname[0] after setting to a time zone 68** in which Standard Time is never observed. 69** 5. They might reference tm.TM_ZONE after calling offtime. 70** What's best to do in the above cases is open to debate; 71** for now, we just set things up so that in any of the five cases 72** WILDABBR is used. Another possibility: initialize tzname[0] to the 73** string "tzname[0] used before set", and similarly for the other cases. 74** And another: initialize tzname[0] to "ERA", with an explanation in the 75** manual page of what this "time zone abbreviation" means (doing this so 76** that tzname[0] has the "normal" length of three characters). 77*/ 78#define WILDABBR " " 79#endif /* !defined WILDABBR */ 80 81static const char wildabbr[] = "WILDABBR"; 82 83static const char gmt[] = "GMT"; 84 85/* 86** The DST rules to use if TZ has no rules and we can't load TZDEFRULES. 87** We default to US rules as of 1999-08-17. 88** POSIX 1003.1 section 8.1.1 says that the default DST rules are 89** implementation dependent; for historical reasons, US rules are a 90** common default. 91*/ 92#ifndef TZDEFRULESTRING 93#define TZDEFRULESTRING ",M4.1.0,M10.5.0" 94#endif /* !defined TZDEFDST */ 95 96struct ttinfo { /* time type information */ 97 long tt_gmtoff; /* UTC offset in seconds */ 98 int tt_isdst; /* used to set tm_isdst */ 99 int tt_abbrind; /* abbreviation list index */ 100 int tt_ttisstd; /* TRUE if transition is std time */ 101 int tt_ttisgmt; /* TRUE if transition is UTC */ 102}; 103 104struct lsinfo { /* leap second information */ 105 time_t ls_trans; /* transition time */ 106 long ls_corr; /* correction to apply */ 107}; 108 109#define BIGGEST(a, b) (((a) > (b)) ? (a) : (b)) 110 111#ifdef TZNAME_MAX 112#define MY_TZNAME_MAX TZNAME_MAX 113#endif /* defined TZNAME_MAX */ 114#ifndef TZNAME_MAX 115#define MY_TZNAME_MAX 255 116#endif /* !defined TZNAME_MAX */ 117 118struct state { 119 int leapcnt; 120 int timecnt; 121 int typecnt; 122 int charcnt; 123 time_t ats[TZ_MAX_TIMES]; 124 unsigned char types[TZ_MAX_TIMES]; 125 struct ttinfo ttis[TZ_MAX_TYPES]; 126 char chars[/* LINTED constant */BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt), 127 (2 * (MY_TZNAME_MAX + 1)))]; 128 struct lsinfo lsis[TZ_MAX_LEAPS]; 129}; 130 131struct rule { 132 int r_type; /* type of rule--see below */ 133 int r_day; /* day number of rule */ 134 int r_week; /* week number of rule */ 135 int r_mon; /* month number of rule */ 136 long r_time; /* transition time of rule */ 137}; 138 139#define JULIAN_DAY 0 /* Jn - Julian day */ 140#define DAY_OF_YEAR 1 /* n - day of year */ 141#define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */ 142 143/* 144** Prototypes for static functions. 145*/ 146 147static long detzcode P((const char * codep)); 148static const char * getzname P((const char * strp)); 149static const char * getnum P((const char * strp, int * nump, int min, 150 int max)); 151static const char * getsecs P((const char * strp, long * secsp)); 152static const char * getoffset P((const char * strp, long * offsetp)); 153static const char * getrule P((const char * strp, struct rule * rulep)); 154static void gmtload P((struct state * sp)); 155static void gmtsub P((const time_t * timep, long offset, 156 struct tm * tmp)); 157static void localsub P((const time_t * timep, long offset, 158 struct tm * tmp)); 159static int increment_overflow P((int * number, int delta)); 160static int normalize_overflow P((int * tensptr, int * unitsptr, 161 int base)); 162static void settzname P((void)); 163static time_t time1 P((struct tm * tmp, 164 void(*funcp) P((const time_t *, 165 long, struct tm *)), 166 long offset)); 167static time_t time2 P((struct tm *tmp, 168 void(*funcp) P((const time_t *, 169 long, struct tm*)), 170 long offset, int * okayp)); 171static time_t time2sub P((struct tm *tmp, 172 void(*funcp) P((const time_t *, 173 long, struct tm*)), 174 long offset, int * okayp, int do_norm_secs)); 175static void timesub P((const time_t * timep, long offset, 176 const struct state * sp, struct tm * tmp)); 177static int tmcomp P((const struct tm * atmp, 178 const struct tm * btmp)); 179static time_t transtime P((time_t janfirst, int year, 180 const struct rule * rulep, long offset)); 181static int tzload P((const char * name, struct state * sp)); 182static int tzparse P((const char * name, struct state * sp, 183 int lastditch)); 184static void tzset_unlocked P((void)); 185static void tzsetwall_unlocked P((void)); 186#ifdef STD_INSPIRED 187static long leapcorr P((time_t * timep)); 188#endif 189 190#ifdef ALL_STATE 191static struct state * lclptr; 192static struct state * gmtptr; 193#endif /* defined ALL_STATE */ 194 195#ifndef ALL_STATE 196static struct state lclmem; 197static struct state gmtmem; 198#define lclptr (&lclmem) 199#define gmtptr (&gmtmem) 200#endif /* State Farm */ 201 202#ifndef TZ_STRLEN_MAX 203#define TZ_STRLEN_MAX 255 204#endif /* !defined TZ_STRLEN_MAX */ 205 206static char lcl_TZname[TZ_STRLEN_MAX + 1]; 207static int lcl_is_set; 208static int gmt_is_set; 209 210__aconst char * tzname[2] = { 211 /* LINTED const castaway */ 212 (__aconst char *)wildabbr, 213 /* LINTED const castaway */ 214 (__aconst char *)wildabbr 215}; 216 217#ifdef _REENTRANT 218static rwlock_t lcl_lock = RWLOCK_INITIALIZER; 219#endif 220 221/* 222** Section 4.12.3 of X3.159-1989 requires that 223** Except for the strftime function, these functions [asctime, 224** ctime, gmtime, localtime] return values in one of two static 225** objects: a broken-down time structure and an array of char. 226** Thanks to Paul Eggert (eggert@twinsun.com) for noting this. 227*/ 228 229static struct tm tm; 230 231#ifdef USG_COMPAT 232long int timezone = 0; 233int daylight = 0; 234#endif /* defined USG_COMPAT */ 235 236#ifdef ALTZONE 237time_t altzone = 0; 238#endif /* defined ALTZONE */ 239 240static long 241detzcode(codep) 242const char * const codep; 243{ 244 register long result; 245 246 /* 247 ** The first character must be sign extended on systems with >32bit 248 ** longs. This was solved differently in the master tzcode sources 249 ** (the fix first appeared in tzcode95c.tar.gz). But I believe 250 ** that this implementation is superior. 251 */ 252 253#define SIGN_EXTEND_CHAR(x) ((signed char) x) 254 255 result = (SIGN_EXTEND_CHAR(codep[0]) << 24) \ 256 | (codep[1] & 0xff) << 16 \ 257 | (codep[2] & 0xff) << 8 258 | (codep[3] & 0xff); 259 return result; 260} 261 262static void 263settzname P((void)) 264{ 265 register struct state * const sp = lclptr; 266 register int i; 267 268 /* LINTED const castaway */ 269 tzname[0] = (__aconst char *)wildabbr; 270 /* LINTED const castaway */ 271 tzname[1] = (__aconst char *)wildabbr; 272#ifdef USG_COMPAT 273 daylight = 0; 274 timezone = 0; 275#endif /* defined USG_COMPAT */ 276#ifdef ALTZONE 277 altzone = 0; 278#endif /* defined ALTZONE */ 279#ifdef ALL_STATE 280 if (sp == NULL) { 281 tzname[0] = tzname[1] = (__aconst char *)gmt; 282 return; 283 } 284#endif /* defined ALL_STATE */ 285 for (i = 0; i < sp->typecnt; ++i) { 286 register const struct ttinfo * const ttisp = &sp->ttis[i]; 287 288 tzname[ttisp->tt_isdst] = 289 &sp->chars[ttisp->tt_abbrind]; 290#ifdef USG_COMPAT 291 if (ttisp->tt_isdst) 292 daylight = 1; 293 if (i == 0 || !ttisp->tt_isdst) 294 timezone = -(ttisp->tt_gmtoff); 295#endif /* defined USG_COMPAT */ 296#ifdef ALTZONE 297 if (i == 0 || ttisp->tt_isdst) 298 altzone = -(ttisp->tt_gmtoff); 299#endif /* defined ALTZONE */ 300 } 301 /* 302 ** And to get the latest zone names into tzname. . . 303 */ 304 for (i = 0; i < sp->timecnt; ++i) { 305 register const struct ttinfo * const ttisp = 306 &sp->ttis[ 307 sp->types[i]]; 308 309 tzname[ttisp->tt_isdst] = 310 &sp->chars[ttisp->tt_abbrind]; 311 } 312} 313 314static int 315tzload(name, sp) 316register const char * name; 317register struct state * const sp; 318{ 319 register const char * p; 320 register int i; 321 register int fid; 322 323 if (name == NULL && (name = TZDEFAULT) == NULL) 324 return -1; 325 326 { 327 register int doaccess; 328 /* 329 ** Section 4.9.1 of the C standard says that 330 ** "FILENAME_MAX expands to an integral constant expression 331 ** that is the size needed for an array of char large enough 332 ** to hold the longest file name string that the implementation 333 ** guarantees can be opened." 334 */ 335 char fullname[FILENAME_MAX + 1]; 336 337 if (name[0] == ':') 338 ++name; 339 doaccess = name[0] == '/'; 340 if (!doaccess) { 341 if ((p = TZDIR) == NULL) 342 return -1; 343 if ((strlen(p) + strlen(name) + 1) >= sizeof fullname) 344 return -1; 345 (void) strcpy(fullname, p); /* XXX strcpy is safe */ 346 (void) strcat(fullname, "/"); /* XXX strcat is safe */ 347 (void) strcat(fullname, name); /* XXX strcat is safe */ 348 /* 349 ** Set doaccess if '.' (as in "../") shows up in name. 350 */ 351 if (strchr(name, '.') != NULL) 352 doaccess = TRUE; 353 name = fullname; 354 } 355 if (doaccess && access(name, R_OK) != 0) 356 return -1; 357 /* 358 * XXX potential security problem here if user of a set-id 359 * program has set TZ (which is passed in as name) here, 360 * and uses a race condition trick to defeat the access(2) 361 * above. 362 */ 363 if ((fid = open(name, OPEN_MODE)) == -1) 364 return -1; 365 } 366 { 367 struct tzhead * tzhp; 368 union { 369 struct tzhead tzhead; 370 char buf[sizeof *sp + sizeof *tzhp]; 371 } u; 372 int ttisstdcnt; 373 int ttisgmtcnt; 374 375 i = read(fid, u.buf, sizeof u.buf); 376 if (close(fid) != 0) 377 return -1; 378 ttisstdcnt = (int) detzcode(u.tzhead.tzh_ttisstdcnt); 379 ttisgmtcnt = (int) detzcode(u.tzhead.tzh_ttisgmtcnt); 380 sp->leapcnt = (int) detzcode(u.tzhead.tzh_leapcnt); 381 sp->timecnt = (int) detzcode(u.tzhead.tzh_timecnt); 382 sp->typecnt = (int) detzcode(u.tzhead.tzh_typecnt); 383 sp->charcnt = (int) detzcode(u.tzhead.tzh_charcnt); 384 p = u.tzhead.tzh_charcnt + sizeof u.tzhead.tzh_charcnt; 385 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS || 386 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES || 387 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES || 388 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS || 389 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) || 390 (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0)) 391 return -1; 392 if (i - (p - u.buf) < sp->timecnt * 4 + /* ats */ 393 sp->timecnt + /* types */ 394 sp->typecnt * (4 + 2) + /* ttinfos */ 395 sp->charcnt + /* chars */ 396 sp->leapcnt * (4 + 4) + /* lsinfos */ 397 ttisstdcnt + /* ttisstds */ 398 ttisgmtcnt) /* ttisgmts */ 399 return -1; 400 for (i = 0; i < sp->timecnt; ++i) { 401 sp->ats[i] = detzcode(p); 402 p += 4; 403 } 404 for (i = 0; i < sp->timecnt; ++i) { 405 sp->types[i] = (unsigned char) *p++; 406 if (sp->types[i] >= sp->typecnt) 407 return -1; 408 } 409 for (i = 0; i < sp->typecnt; ++i) { 410 register struct ttinfo * ttisp; 411 412 ttisp = &sp->ttis[i]; 413 ttisp->tt_gmtoff = detzcode(p); 414 p += 4; 415 ttisp->tt_isdst = (unsigned char) *p++; 416 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1) 417 return -1; 418 ttisp->tt_abbrind = (unsigned char) *p++; 419 if (ttisp->tt_abbrind < 0 || 420 ttisp->tt_abbrind > sp->charcnt) 421 return -1; 422 } 423 for (i = 0; i < sp->charcnt; ++i) 424 sp->chars[i] = *p++; 425 sp->chars[i] = '\0'; /* ensure '\0' at end */ 426 for (i = 0; i < sp->leapcnt; ++i) { 427 register struct lsinfo * lsisp; 428 429 lsisp = &sp->lsis[i]; 430 lsisp->ls_trans = detzcode(p); 431 p += 4; 432 lsisp->ls_corr = detzcode(p); 433 p += 4; 434 } 435 for (i = 0; i < sp->typecnt; ++i) { 436 register struct ttinfo * ttisp; 437 438 ttisp = &sp->ttis[i]; 439 if (ttisstdcnt == 0) 440 ttisp->tt_ttisstd = FALSE; 441 else { 442 ttisp->tt_ttisstd = *p++; 443 if (ttisp->tt_ttisstd != TRUE && 444 ttisp->tt_ttisstd != FALSE) 445 return -1; 446 } 447 } 448 for (i = 0; i < sp->typecnt; ++i) { 449 register struct ttinfo * ttisp; 450 451 ttisp = &sp->ttis[i]; 452 if (ttisgmtcnt == 0) 453 ttisp->tt_ttisgmt = FALSE; 454 else { 455 ttisp->tt_ttisgmt = *p++; 456 if (ttisp->tt_ttisgmt != TRUE && 457 ttisp->tt_ttisgmt != FALSE) 458 return -1; 459 } 460 } 461 } 462 return 0; 463} 464 465static const int mon_lengths[2][MONSPERYEAR] = { 466 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, 467 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } 468}; 469 470static const int year_lengths[2] = { 471 DAYSPERNYEAR, DAYSPERLYEAR 472}; 473 474/* 475** Given a pointer into a time zone string, scan until a character that is not 476** a valid character in a zone name is found. Return a pointer to that 477** character. 478*/ 479 480static const char * 481getzname(strp) 482register const char * strp; 483{ 484 register char c; 485 486 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && 487 c != '+') 488 ++strp; 489 return strp; 490} 491 492/* 493** Given a pointer into a time zone string, extract a number from that string. 494** Check that the number is within a specified range; if it is not, return 495** NULL. 496** Otherwise, return a pointer to the first character not part of the number. 497*/ 498 499static const char * 500getnum(strp, nump, min, max) 501register const char * strp; 502int * const nump; 503const int min; 504const int max; 505{ 506 register char c; 507 register int num; 508 509 if (strp == NULL || !is_digit(c = *strp)) 510 return NULL; 511 num = 0; 512 do { 513 num = num * 10 + (c - '0'); 514 if (num > max) 515 return NULL; /* illegal value */ 516 c = *++strp; 517 } while (is_digit(c)); 518 if (num < min) 519 return NULL; /* illegal value */ 520 *nump = num; 521 return strp; 522} 523 524/* 525** Given a pointer into a time zone string, extract a number of seconds, 526** in hh[:mm[:ss]] form, from the string. 527** If any error occurs, return NULL. 528** Otherwise, return a pointer to the first character not part of the number 529** of seconds. 530*/ 531 532static const char * 533getsecs(strp, secsp) 534register const char * strp; 535long * const secsp; 536{ 537 int num; 538 539 /* 540 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like 541 ** "M10.4.6/26", which does not conform to Posix, 542 ** but which specifies the equivalent of 543 ** ``02:00 on the first Sunday on or after 23 Oct''. 544 */ 545 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); 546 if (strp == NULL) 547 return NULL; 548 *secsp = num * (long) SECSPERHOUR; 549 if (*strp == ':') { 550 ++strp; 551 strp = getnum(strp, &num, 0, MINSPERHOUR - 1); 552 if (strp == NULL) 553 return NULL; 554 *secsp += num * SECSPERMIN; 555 if (*strp == ':') { 556 ++strp; 557 /* `SECSPERMIN' allows for leap seconds. */ 558 strp = getnum(strp, &num, 0, SECSPERMIN); 559 if (strp == NULL) 560 return NULL; 561 *secsp += num; 562 } 563 } 564 return strp; 565} 566 567/* 568** Given a pointer into a time zone string, extract an offset, in 569** [+-]hh[:mm[:ss]] form, from the string. 570** If any error occurs, return NULL. 571** Otherwise, return a pointer to the first character not part of the time. 572*/ 573 574static const char * 575getoffset(strp, offsetp) 576register const char * strp; 577long * const offsetp; 578{ 579 register int neg = 0; 580 581 if (*strp == '-') { 582 neg = 1; 583 ++strp; 584 } else if (*strp == '+') 585 ++strp; 586 strp = getsecs(strp, offsetp); 587 if (strp == NULL) 588 return NULL; /* illegal time */ 589 if (neg) 590 *offsetp = -*offsetp; 591 return strp; 592} 593 594/* 595** Given a pointer into a time zone string, extract a rule in the form 596** date[/time]. See POSIX section 8 for the format of "date" and "time". 597** If a valid rule is not found, return NULL. 598** Otherwise, return a pointer to the first character not part of the rule. 599*/ 600 601static const char * 602getrule(strp, rulep) 603const char * strp; 604register struct rule * const rulep; 605{ 606 if (*strp == 'J') { 607 /* 608 ** Julian day. 609 */ 610 rulep->r_type = JULIAN_DAY; 611 ++strp; 612 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); 613 } else if (*strp == 'M') { 614 /* 615 ** Month, week, day. 616 */ 617 rulep->r_type = MONTH_NTH_DAY_OF_WEEK; 618 ++strp; 619 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); 620 if (strp == NULL) 621 return NULL; 622 if (*strp++ != '.') 623 return NULL; 624 strp = getnum(strp, &rulep->r_week, 1, 5); 625 if (strp == NULL) 626 return NULL; 627 if (*strp++ != '.') 628 return NULL; 629 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); 630 } else if (is_digit(*strp)) { 631 /* 632 ** Day of year. 633 */ 634 rulep->r_type = DAY_OF_YEAR; 635 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); 636 } else return NULL; /* invalid format */ 637 if (strp == NULL) 638 return NULL; 639 if (*strp == '/') { 640 /* 641 ** Time specified. 642 */ 643 ++strp; 644 strp = getsecs(strp, &rulep->r_time); 645 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ 646 return strp; 647} 648 649/* 650** Given the Epoch-relative time of January 1, 00:00:00 UTC, in a year, the 651** year, a rule, and the offset from UTC at the time that rule takes effect, 652** calculate the Epoch-relative time that rule takes effect. 653*/ 654 655static time_t 656transtime(janfirst, year, rulep, offset) 657const time_t janfirst; 658const int year; 659register const struct rule * const rulep; 660const long offset; 661{ 662 register int leapyear; 663 register time_t value; 664 register int i; 665 int d, m1, yy0, yy1, yy2, dow; 666 667 INITIALIZE(value); 668 leapyear = isleap(year); 669 switch (rulep->r_type) { 670 671 case JULIAN_DAY: 672 /* 673 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap 674 ** years. 675 ** In non-leap years, or if the day number is 59 or less, just 676 ** add SECSPERDAY times the day number-1 to the time of 677 ** January 1, midnight, to get the day. 678 */ 679 value = janfirst + (rulep->r_day - 1) * SECSPERDAY; 680 if (leapyear && rulep->r_day >= 60) 681 value += SECSPERDAY; 682 break; 683 684 case DAY_OF_YEAR: 685 /* 686 ** n - day of year. 687 ** Just add SECSPERDAY times the day number to the time of 688 ** January 1, midnight, to get the day. 689 */ 690 value = janfirst + rulep->r_day * SECSPERDAY; 691 break; 692 693 case MONTH_NTH_DAY_OF_WEEK: 694 /* 695 ** Mm.n.d - nth "dth day" of month m. 696 */ 697 value = janfirst; 698 for (i = 0; i < rulep->r_mon - 1; ++i) 699 value += mon_lengths[leapyear][i] * SECSPERDAY; 700 701 /* 702 ** Use Zeller's Congruence to get day-of-week of first day of 703 ** month. 704 */ 705 m1 = (rulep->r_mon + 9) % 12 + 1; 706 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; 707 yy1 = yy0 / 100; 708 yy2 = yy0 % 100; 709 dow = ((26 * m1 - 2) / 10 + 710 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; 711 if (dow < 0) 712 dow += DAYSPERWEEK; 713 714 /* 715 ** "dow" is the day-of-week of the first day of the month. Get 716 ** the day-of-month (zero-origin) of the first "dow" day of the 717 ** month. 718 */ 719 d = rulep->r_day - dow; 720 if (d < 0) 721 d += DAYSPERWEEK; 722 for (i = 1; i < rulep->r_week; ++i) { 723 if (d + DAYSPERWEEK >= 724 mon_lengths[leapyear][rulep->r_mon - 1]) 725 break; 726 d += DAYSPERWEEK; 727 } 728 729 /* 730 ** "d" is the day-of-month (zero-origin) of the day we want. 731 */ 732 value += d * SECSPERDAY; 733 break; 734 } 735 736 /* 737 ** "value" is the Epoch-relative time of 00:00:00 UTC on the day in 738 ** question. To get the Epoch-relative time of the specified local 739 ** time on that day, add the transition time and the current offset 740 ** from UTC. 741 */ 742 return value + rulep->r_time + offset; 743} 744 745/* 746** Given a POSIX section 8-style TZ string, fill in the rule tables as 747** appropriate. 748*/ 749 750static int 751tzparse(name, sp, lastditch) 752const char * name; 753register struct state * const sp; 754const int lastditch; 755{ 756 const char * stdname; 757 const char * dstname; 758 size_t stdlen; 759 size_t dstlen; 760 long stdoffset; 761 long dstoffset; 762 register time_t * atp; 763 register unsigned char * typep; 764 register char * cp; 765 register int load_result; 766 767 INITIALIZE(dstname); 768 stdname = name; 769 if (lastditch) { 770 stdlen = strlen(name); /* length of standard zone name */ 771 name += stdlen; 772 if (stdlen >= sizeof sp->chars) 773 stdlen = (sizeof sp->chars) - 1; 774 stdoffset = 0; 775 } else { 776 name = getzname(name); 777 stdlen = name - stdname; 778 if (stdlen < 3) 779 return -1; 780 if (*name == '\0') 781 return -1; 782 name = getoffset(name, &stdoffset); 783 if (name == NULL) 784 return -1; 785 } 786 load_result = tzload(TZDEFRULES, sp); 787 if (load_result != 0) 788 sp->leapcnt = 0; /* so, we're off a little */ 789 if (*name != '\0') { 790 dstname = name; 791 name = getzname(name); 792 dstlen = name - dstname; /* length of DST zone name */ 793 if (dstlen < 3) 794 return -1; 795 if (*name != '\0' && *name != ',' && *name != ';') { 796 name = getoffset(name, &dstoffset); 797 if (name == NULL) 798 return -1; 799 } else dstoffset = stdoffset - SECSPERHOUR; 800 if (*name == '\0' && load_result != 0) 801 name = TZDEFRULESTRING; 802 if (*name == ',' || *name == ';') { 803 struct rule start; 804 struct rule end; 805 register int year; 806 register time_t janfirst; 807 time_t starttime; 808 time_t endtime; 809 810 ++name; 811 if ((name = getrule(name, &start)) == NULL) 812 return -1; 813 if (*name++ != ',') 814 return -1; 815 if ((name = getrule(name, &end)) == NULL) 816 return -1; 817 if (*name != '\0') 818 return -1; 819 sp->typecnt = 2; /* standard time and DST */ 820 /* 821 ** Two transitions per year, from EPOCH_YEAR to 2037. 822 */ 823 sp->timecnt = 2 * (2037 - EPOCH_YEAR + 1); 824 if (sp->timecnt > TZ_MAX_TIMES) 825 return -1; 826 sp->ttis[0].tt_gmtoff = -dstoffset; 827 sp->ttis[0].tt_isdst = 1; 828 sp->ttis[0].tt_abbrind = stdlen + 1; 829 sp->ttis[1].tt_gmtoff = -stdoffset; 830 sp->ttis[1].tt_isdst = 0; 831 sp->ttis[1].tt_abbrind = 0; 832 atp = sp->ats; 833 typep = sp->types; 834 janfirst = 0; 835 for (year = EPOCH_YEAR; year <= 2037; ++year) { 836 starttime = transtime(janfirst, year, &start, 837 stdoffset); 838 endtime = transtime(janfirst, year, &end, 839 dstoffset); 840 if (starttime > endtime) { 841 *atp++ = endtime; 842 *typep++ = 1; /* DST ends */ 843 *atp++ = starttime; 844 *typep++ = 0; /* DST begins */ 845 } else { 846 *atp++ = starttime; 847 *typep++ = 0; /* DST begins */ 848 *atp++ = endtime; 849 *typep++ = 1; /* DST ends */ 850 } 851 janfirst += year_lengths[isleap(year)] * 852 SECSPERDAY; 853 } 854 } else { 855 register long theirstdoffset; 856 register long theirdstoffset; 857 register long theiroffset; 858 register int isdst; 859 register int i; 860 register int j; 861 862 if (*name != '\0') 863 return -1; 864 /* 865 ** Initial values of theirstdoffset and theirdstoffset. 866 */ 867 theirstdoffset = 0; 868 for (i = 0; i < sp->timecnt; ++i) { 869 j = sp->types[i]; 870 if (!sp->ttis[j].tt_isdst) { 871 theirstdoffset = 872 -sp->ttis[j].tt_gmtoff; 873 break; 874 } 875 } 876 theirdstoffset = 0; 877 for (i = 0; i < sp->timecnt; ++i) { 878 j = sp->types[i]; 879 if (sp->ttis[j].tt_isdst) { 880 theirdstoffset = 881 -sp->ttis[j].tt_gmtoff; 882 break; 883 } 884 } 885 /* 886 ** Initially we're assumed to be in standard time. 887 */ 888 isdst = FALSE; 889 theiroffset = theirstdoffset; 890 /* 891 ** Now juggle transition times and types 892 ** tracking offsets as you do. 893 */ 894 for (i = 0; i < sp->timecnt; ++i) { 895 j = sp->types[i]; 896 sp->types[i] = sp->ttis[j].tt_isdst; 897 if (sp->ttis[j].tt_ttisgmt) { 898 /* No adjustment to transition time */ 899 } else { 900 /* 901 ** If summer time is in effect, and the 902 ** transition time was not specified as 903 ** standard time, add the summer time 904 ** offset to the transition time; 905 ** otherwise, add the standard time 906 ** offset to the transition time. 907 */ 908 /* 909 ** Transitions from DST to DDST 910 ** will effectively disappear since 911 ** POSIX provides for only one DST 912 ** offset. 913 */ 914 if (isdst && !sp->ttis[j].tt_ttisstd) { 915 sp->ats[i] += dstoffset - 916 theirdstoffset; 917 } else { 918 sp->ats[i] += stdoffset - 919 theirstdoffset; 920 } 921 } 922 theiroffset = -sp->ttis[j].tt_gmtoff; 923 if (sp->ttis[j].tt_isdst) 924 theirdstoffset = theiroffset; 925 else theirstdoffset = theiroffset; 926 } 927 /* 928 ** Finally, fill in ttis. 929 ** ttisstd and ttisgmt need not be handled. 930 */ 931 sp->ttis[0].tt_gmtoff = -stdoffset; 932 sp->ttis[0].tt_isdst = FALSE; 933 sp->ttis[0].tt_abbrind = 0; 934 sp->ttis[1].tt_gmtoff = -dstoffset; 935 sp->ttis[1].tt_isdst = TRUE; 936 sp->ttis[1].tt_abbrind = stdlen + 1; 937 sp->typecnt = 2; 938 } 939 } else { 940 dstlen = 0; 941 sp->typecnt = 1; /* only standard time */ 942 sp->timecnt = 0; 943 sp->ttis[0].tt_gmtoff = -stdoffset; 944 sp->ttis[0].tt_isdst = 0; 945 sp->ttis[0].tt_abbrind = 0; 946 } 947 sp->charcnt = stdlen + 1; 948 if (dstlen != 0) 949 sp->charcnt += dstlen + 1; 950 if ((size_t) sp->charcnt > sizeof sp->chars) 951 return -1; 952 cp = sp->chars; 953 (void) strncpy(cp, stdname, stdlen); 954 cp += stdlen; 955 *cp++ = '\0'; 956 if (dstlen != 0) { 957 (void) strncpy(cp, dstname, dstlen); 958 *(cp + dstlen) = '\0'; 959 } 960 return 0; 961} 962 963static void 964gmtload(sp) 965struct state * const sp; 966{ 967 if (tzload(gmt, sp) != 0) 968 (void) tzparse(gmt, sp, TRUE); 969} 970 971static void 972tzsetwall_unlocked P((void)) 973{ 974 if (lcl_is_set < 0) 975 return; 976 lcl_is_set = -1; 977 978#ifdef ALL_STATE 979 if (lclptr == NULL) { 980 lclptr = (struct state *) malloc(sizeof *lclptr); 981 if (lclptr == NULL) { 982 settzname(); /* all we can do */ 983 return; 984 } 985 } 986#endif /* defined ALL_STATE */ 987 if (tzload((char *) NULL, lclptr) != 0) 988 gmtload(lclptr); 989 settzname(); 990} 991 992#ifndef STD_INSPIRED 993/* 994** A non-static declaration of tzsetwall in a system header file 995** may cause a warning about this upcoming static declaration... 996*/ 997static 998#endif /* !defined STD_INSPIRED */ 999void 1000tzsetwall P((void)) 1001{ 1002 rwlock_wrlock(&lcl_lock); 1003 tzsetwall_unlocked(); 1004 rwlock_unlock(&lcl_lock); 1005} 1006 1007static void 1008tzset_unlocked P((void)) 1009{ 1010 register const char * name; 1011 1012 name = getenv("TZ"); 1013 if (name == NULL) { 1014 tzsetwall_unlocked(); 1015 return; 1016 } 1017 1018 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) 1019 return; 1020 lcl_is_set = strlen(name) < sizeof lcl_TZname; 1021 if (lcl_is_set) 1022 (void)strlcpy(lcl_TZname, name, sizeof(lcl_TZname)); 1023 1024#ifdef ALL_STATE 1025 if (lclptr == NULL) { 1026 lclptr = (struct state *) malloc(sizeof *lclptr); 1027 if (lclptr == NULL) { 1028 settzname(); /* all we can do */ 1029 return; 1030 } 1031 } 1032#endif /* defined ALL_STATE */ 1033 if (*name == '\0') { 1034 /* 1035 ** User wants it fast rather than right. 1036 */ 1037 lclptr->leapcnt = 0; /* so, we're off a little */ 1038 lclptr->timecnt = 0; 1039 lclptr->typecnt = 0; 1040 lclptr->ttis[0].tt_isdst = 0; 1041 lclptr->ttis[0].tt_gmtoff = 0; 1042 lclptr->ttis[0].tt_abbrind = 0; 1043 (void)strlcpy(lclptr->chars, gmt, sizeof(lclptr->chars)); 1044 } else if (tzload(name, lclptr) != 0) 1045 if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0) 1046 (void) gmtload(lclptr); 1047 settzname(); 1048} 1049 1050void 1051tzset P((void)) 1052{ 1053 rwlock_wrlock(&lcl_lock); 1054 tzset_unlocked(); 1055 rwlock_unlock(&lcl_lock); 1056} 1057 1058/* 1059** The easy way to behave "as if no library function calls" localtime 1060** is to not call it--so we drop its guts into "localsub", which can be 1061** freely called. (And no, the PANS doesn't require the above behavior-- 1062** but it *is* desirable.) 1063** 1064** The unused offset argument is for the benefit of mktime variants. 1065*/ 1066 1067/*ARGSUSED*/ 1068static void 1069localsub(timep, offset, tmp) 1070const time_t * const timep; 1071const long offset; 1072struct tm * const tmp; 1073{ 1074 register struct state * sp; 1075 register const struct ttinfo * ttisp; 1076 register int i; 1077 const time_t t = *timep; 1078 1079 sp = lclptr; 1080#ifdef ALL_STATE 1081 if (sp == NULL) { 1082 gmtsub(timep, offset, tmp); 1083 return; 1084 } 1085#endif /* defined ALL_STATE */ 1086 if (sp->timecnt == 0 || t < sp->ats[0]) { 1087 i = 0; 1088 while (sp->ttis[i].tt_isdst) 1089 if (++i >= sp->typecnt) { 1090 i = 0; 1091 break; 1092 } 1093 } else { 1094 for (i = 1; i < sp->timecnt; ++i) 1095 if (t < sp->ats[i]) 1096 break; 1097 i = sp->types[i - 1]; 1098 } 1099 ttisp = &sp->ttis[i]; 1100 /* 1101 ** To get (wrong) behavior that's compatible with System V Release 2.0 1102 ** you'd replace the statement below with 1103 ** t += ttisp->tt_gmtoff; 1104 ** timesub(&t, 0L, sp, tmp); 1105 */ 1106 timesub(&t, ttisp->tt_gmtoff, sp, tmp); 1107 tmp->tm_isdst = ttisp->tt_isdst; 1108 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind]; 1109#ifdef TM_ZONE 1110 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind]; 1111#endif /* defined TM_ZONE */ 1112} 1113 1114struct tm * 1115localtime(timep) 1116const time_t * const timep; 1117{ 1118 rwlock_wrlock(&lcl_lock); 1119 tzset_unlocked(); 1120 localsub(timep, 0L, &tm); 1121 rwlock_unlock(&lcl_lock); 1122 return &tm; 1123} 1124 1125/* 1126 * Re-entrant version of localtime 1127 */ 1128struct tm * 1129localtime_r(timep, tmp) 1130const time_t * const timep; 1131struct tm * tmp; 1132{ 1133 rwlock_rdlock(&lcl_lock); 1134 localsub(timep, 0L, tmp); 1135 rwlock_unlock(&lcl_lock); 1136 return tmp; 1137} 1138 1139/* 1140** gmtsub is to gmtime as localsub is to localtime. 1141*/ 1142 1143static void 1144gmtsub(timep, offset, tmp) 1145const time_t * const timep; 1146const long offset; 1147struct tm * const tmp; 1148{ 1149#ifdef _REENTRANT 1150 static mutex_t gmt_mutex = MUTEX_INITIALIZER; 1151#endif 1152 1153 mutex_lock(&gmt_mutex); 1154 if (!gmt_is_set) { 1155 gmt_is_set = TRUE; 1156#ifdef ALL_STATE 1157 gmtptr = (struct state *) malloc(sizeof *gmtptr); 1158 if (gmtptr != NULL) 1159#endif /* defined ALL_STATE */ 1160 gmtload(gmtptr); 1161 } 1162 mutex_unlock(&gmt_mutex); 1163 timesub(timep, offset, gmtptr, tmp); 1164#ifdef TM_ZONE 1165 /* 1166 ** Could get fancy here and deliver something such as 1167 ** "UTC+xxxx" or "UTC-xxxx" if offset is non-zero, 1168 ** but this is no time for a treasure hunt. 1169 */ 1170 if (offset != 0) 1171 /* LINTED const castaway */ 1172 tmp->TM_ZONE = (__aconst char *)wildabbr; 1173 else { 1174#ifdef ALL_STATE 1175 if (gmtptr == NULL) 1176 tmp->TM_ZONE = (__aconst char *)gmt; 1177 else tmp->TM_ZONE = gmtptr->chars; 1178#endif /* defined ALL_STATE */ 1179#ifndef ALL_STATE 1180 tmp->TM_ZONE = gmtptr->chars; 1181#endif /* State Farm */ 1182 } 1183#endif /* defined TM_ZONE */ 1184} 1185 1186struct tm * 1187gmtime(timep) 1188const time_t * const timep; 1189{ 1190 gmtsub(timep, 0L, &tm); 1191 return &tm; 1192} 1193 1194/* 1195 * Re-entrant version of gmtime 1196 */ 1197struct tm * 1198gmtime_r(timep, tmp) 1199const time_t * const timep; 1200struct tm * tmp; 1201{ 1202 gmtsub(timep, 0L, tmp); 1203 return tmp; 1204} 1205 1206#ifdef STD_INSPIRED 1207 1208struct tm * 1209offtime(timep, offset) 1210const time_t * const timep; 1211const long offset; 1212{ 1213 gmtsub(timep, offset, &tm); 1214 return &tm; 1215} 1216 1217#endif /* defined STD_INSPIRED */ 1218 1219static void 1220timesub(timep, offset, sp, tmp) 1221const time_t * const timep; 1222const long offset; 1223register const struct state * const sp; 1224register struct tm * const tmp; 1225{ 1226 register const struct lsinfo * lp; 1227 register long days; 1228 register long rem; 1229 register int y; 1230 register int yleap; 1231 register const int * ip; 1232 register long corr; 1233 register int hit; 1234 register int i; 1235 1236 corr = 0; 1237 hit = 0; 1238#ifdef ALL_STATE 1239 i = (sp == NULL) ? 0 : sp->leapcnt; 1240#endif /* defined ALL_STATE */ 1241#ifndef ALL_STATE 1242 i = sp->leapcnt; 1243#endif /* State Farm */ 1244 while (--i >= 0) { 1245 lp = &sp->lsis[i]; 1246 if (*timep >= lp->ls_trans) { 1247 if (*timep == lp->ls_trans) { 1248 hit = ((i == 0 && lp->ls_corr > 0) || 1249 lp->ls_corr > sp->lsis[i - 1].ls_corr); 1250 if (hit) 1251 while (i > 0 && 1252 sp->lsis[i].ls_trans == 1253 sp->lsis[i - 1].ls_trans + 1 && 1254 sp->lsis[i].ls_corr == 1255 sp->lsis[i - 1].ls_corr + 1) { 1256 ++hit; 1257 --i; 1258 } 1259 } 1260 corr = lp->ls_corr; 1261 break; 1262 } 1263 } 1264 days = *timep / SECSPERDAY; 1265 rem = *timep % SECSPERDAY; 1266#ifdef mc68k 1267 if (*timep == 0x80000000) { 1268 /* 1269 ** A 3B1 muffs the division on the most negative number. 1270 */ 1271 days = -24855; 1272 rem = -11648; 1273 } 1274#endif /* defined mc68k */ 1275 rem += (offset - corr); 1276 while (rem < 0) { 1277 rem += SECSPERDAY; 1278 --days; 1279 } 1280 while (rem >= SECSPERDAY) { 1281 rem -= SECSPERDAY; 1282 ++days; 1283 } 1284 tmp->tm_hour = (int) (rem / SECSPERHOUR); 1285 rem = rem % SECSPERHOUR; 1286 tmp->tm_min = (int) (rem / SECSPERMIN); 1287 /* 1288 ** A positive leap second requires a special 1289 ** representation. This uses "... ??:59:60" et seq. 1290 */ 1291 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit; 1292 tmp->tm_wday = (int) ((EPOCH_WDAY + days) % DAYSPERWEEK); 1293 if (tmp->tm_wday < 0) 1294 tmp->tm_wday += DAYSPERWEEK; 1295 y = EPOCH_YEAR; 1296#define LEAPS_THRU_END_OF(y) ((y) / 4 - (y) / 100 + (y) / 400) 1297 while (days < 0 || days >= (long) year_lengths[yleap = isleap(y)]) { 1298 register int newy; 1299 1300 newy = (int)(y + days / DAYSPERNYEAR); 1301 if (days < 0) 1302 --newy; 1303 days -= (newy - y) * DAYSPERNYEAR + 1304 LEAPS_THRU_END_OF(newy - 1) - 1305 LEAPS_THRU_END_OF(y - 1); 1306 y = newy; 1307 } 1308 tmp->tm_year = y - TM_YEAR_BASE; 1309 tmp->tm_yday = (int) days; 1310 ip = mon_lengths[yleap]; 1311 for (tmp->tm_mon = 0; days >= (long) ip[tmp->tm_mon]; ++(tmp->tm_mon)) 1312 days = days - (long) ip[tmp->tm_mon]; 1313 tmp->tm_mday = (int) (days + 1); 1314 tmp->tm_isdst = 0; 1315#ifdef TM_GMTOFF 1316 tmp->TM_GMTOFF = offset; 1317#endif /* defined TM_GMTOFF */ 1318} 1319 1320char * 1321ctime(timep) 1322const time_t * const timep; 1323{ 1324/* 1325** Section 4.12.3.2 of X3.159-1989 requires that 1326** The ctime function converts the calendar time pointed to by timer 1327** to local time in the form of a string. It is equivalent to 1328** asctime(localtime(timer)) 1329*/ 1330 return asctime(localtime(timep)); 1331} 1332 1333char * 1334ctime_r(timep, buf) 1335const time_t * const timep; 1336char * buf; 1337{ 1338 struct tm tmp; 1339 1340 return asctime_r(localtime_r(timep, &tmp), buf); 1341} 1342 1343/* 1344** Adapted from code provided by Robert Elz, who writes: 1345** The "best" way to do mktime I think is based on an idea of Bob 1346** Kridle's (so its said...) from a long time ago. 1347** [kridle@xinet.com as of 1996-01-16.] 1348** It does a binary search of the time_t space. Since time_t's are 1349** just 32 bits, its a max of 32 iterations (even at 64 bits it 1350** would still be very reasonable). 1351*/ 1352 1353#ifndef WRONG 1354#define WRONG (-1) 1355#endif /* !defined WRONG */ 1356 1357/* 1358** Simplified normalize logic courtesy Paul Eggert (eggert@twinsun.com). 1359*/ 1360 1361static int 1362increment_overflow(number, delta) 1363int * number; 1364int delta; 1365{ 1366 int number0; 1367 1368 number0 = *number; 1369 *number += delta; 1370 return (*number < number0) != (delta < 0); 1371} 1372 1373static int 1374normalize_overflow(tensptr, unitsptr, base) 1375int * const tensptr; 1376int * const unitsptr; 1377const int base; 1378{ 1379 register int tensdelta; 1380 1381 tensdelta = (*unitsptr >= 0) ? 1382 (*unitsptr / base) : 1383 (-1 - (-1 - *unitsptr) / base); 1384 *unitsptr -= tensdelta * base; 1385 return increment_overflow(tensptr, tensdelta); 1386} 1387 1388static int 1389tmcomp(atmp, btmp) 1390register const struct tm * const atmp; 1391register const struct tm * const btmp; 1392{ 1393 register int result; 1394 1395 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 && 1396 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 && 1397 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && 1398 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && 1399 (result = (atmp->tm_min - btmp->tm_min)) == 0) 1400 result = atmp->tm_sec - btmp->tm_sec; 1401 return result; 1402} 1403 1404static time_t 1405time2sub(tmp, funcp, offset, okayp, do_norm_secs) 1406struct tm * const tmp; 1407void (* const funcp) P((const time_t*, long, struct tm*)); 1408const long offset; 1409int * const okayp; 1410const int do_norm_secs; 1411{ 1412 register const struct state * sp; 1413 register int dir; 1414 register int bits; 1415 register int i, j ; 1416 register int saved_seconds; 1417 time_t newt; 1418 time_t t; 1419 struct tm yourtm, mytm; 1420 1421 *okayp = FALSE; 1422 yourtm = *tmp; 1423 if (do_norm_secs) { 1424 if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec, 1425 SECSPERMIN)) 1426 return WRONG; 1427 } 1428 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) 1429 return WRONG; 1430 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) 1431 return WRONG; 1432 if (normalize_overflow(&yourtm.tm_year, &yourtm.tm_mon, MONSPERYEAR)) 1433 return WRONG; 1434 /* 1435 ** Turn yourtm.tm_year into an actual year number for now. 1436 ** It is converted back to an offset from TM_YEAR_BASE later. 1437 */ 1438 if (increment_overflow(&yourtm.tm_year, TM_YEAR_BASE)) 1439 return WRONG; 1440 while (yourtm.tm_mday <= 0) { 1441 if (increment_overflow(&yourtm.tm_year, -1)) 1442 return WRONG; 1443 i = yourtm.tm_year + (1 < yourtm.tm_mon); 1444 yourtm.tm_mday += year_lengths[isleap(i)]; 1445 } 1446 while (yourtm.tm_mday > DAYSPERLYEAR) { 1447 i = yourtm.tm_year + (1 < yourtm.tm_mon); 1448 yourtm.tm_mday -= year_lengths[isleap(i)]; 1449 if (increment_overflow(&yourtm.tm_year, 1)) 1450 return WRONG; 1451 } 1452 for ( ; ; ) { 1453 i = mon_lengths[isleap(yourtm.tm_year)][yourtm.tm_mon]; 1454 if (yourtm.tm_mday <= i) 1455 break; 1456 yourtm.tm_mday -= i; 1457 if (++yourtm.tm_mon >= MONSPERYEAR) { 1458 yourtm.tm_mon = 0; 1459 if (increment_overflow(&yourtm.tm_year, 1)) 1460 return WRONG; 1461 } 1462 } 1463 if (increment_overflow(&yourtm.tm_year, -TM_YEAR_BASE)) 1464 return WRONG; 1465 if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN) 1466 saved_seconds = 0; 1467 else if (yourtm.tm_year + TM_YEAR_BASE < EPOCH_YEAR) { 1468 /* 1469 ** We can't set tm_sec to 0, because that might push the 1470 ** time below the minimum representable time. 1471 ** Set tm_sec to 59 instead. 1472 ** This assumes that the minimum representable time is 1473 ** not in the same minute that a leap second was deleted from, 1474 ** which is a safer assumption than using 58 would be. 1475 */ 1476 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) 1477 return WRONG; 1478 saved_seconds = yourtm.tm_sec; 1479 yourtm.tm_sec = SECSPERMIN - 1; 1480 } else { 1481 saved_seconds = yourtm.tm_sec; 1482 yourtm.tm_sec = 0; 1483 } 1484 /* 1485 ** Divide the search space in half 1486 ** (this works whether time_t is signed or unsigned). 1487 */ 1488 bits = TYPE_BIT(time_t) - 1; 1489 /* 1490 ** If time_t is signed, then 0 is just above the median, 1491 ** assuming two's complement arithmetic. 1492 ** If time_t is unsigned, then (1 << bits) is just above the median. 1493 */ 1494 /* LINTED constant in conditional context */ 1495 t = TYPE_SIGNED(time_t) ? 0 : (((time_t) 1) << bits); 1496 for ( ; ; ) { 1497 (*funcp)(&t, offset, &mytm); 1498 dir = tmcomp(&mytm, &yourtm); 1499 if (dir != 0) { 1500 if (bits-- < 0) 1501 return WRONG; 1502 if (bits < 0) 1503 --t; /* may be needed if new t is minimal */ 1504 else if (dir > 0) 1505 t -= ((time_t) 1) << bits; 1506 else t += ((time_t) 1) << bits; 1507 continue; 1508 } 1509 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) 1510 break; 1511 /* 1512 ** Right time, wrong type. 1513 ** Hunt for right time, right type. 1514 ** It's okay to guess wrong since the guess 1515 ** gets checked. 1516 */ 1517 /* 1518 ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's. 1519 */ 1520 sp = (const struct state *) 1521 (((void *) funcp == (void *) localsub) ? 1522 lclptr : gmtptr); 1523#ifdef ALL_STATE 1524 if (sp == NULL) 1525 return WRONG; 1526#endif /* defined ALL_STATE */ 1527 for (i = sp->typecnt - 1; i >= 0; --i) { 1528 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) 1529 continue; 1530 for (j = sp->typecnt - 1; j >= 0; --j) { 1531 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) 1532 continue; 1533 newt = t + sp->ttis[j].tt_gmtoff - 1534 sp->ttis[i].tt_gmtoff; 1535 (*funcp)(&newt, offset, &mytm); 1536 if (tmcomp(&mytm, &yourtm) != 0) 1537 continue; 1538 if (mytm.tm_isdst != yourtm.tm_isdst) 1539 continue; 1540 /* 1541 ** We have a match. 1542 */ 1543 t = newt; 1544 goto label; 1545 } 1546 } 1547 return WRONG; 1548 } 1549label: 1550 newt = t + saved_seconds; 1551 if ((newt < t) != (saved_seconds < 0)) 1552 return WRONG; 1553 t = newt; 1554 (*funcp)(&t, offset, tmp); 1555 *okayp = TRUE; 1556 return t; 1557} 1558 1559static time_t 1560time2(tmp, funcp, offset, okayp) 1561struct tm * const tmp; 1562void (* const funcp) P((const time_t*, long, struct tm*)); 1563const long offset; 1564int * const okayp; 1565{ 1566 time_t t; 1567 1568 /* 1569 ** First try without normalization of seconds 1570 ** (in case tm_sec contains a value associated with a leap second). 1571 ** If that fails, try with normalization of seconds. 1572 */ 1573 t = time2sub(tmp, funcp, offset, okayp, FALSE); 1574 return *okayp ? t : time2sub(tmp, funcp, offset, okayp, TRUE); 1575} 1576 1577static time_t 1578time1(tmp, funcp, offset) 1579struct tm * const tmp; 1580void (* const funcp) P((const time_t *, long, struct tm *)); 1581const long offset; 1582{ 1583 register time_t t; 1584 register const struct state * sp; 1585 register int samei, otheri; 1586 int okay; 1587 1588 if (tmp->tm_isdst > 1) 1589 tmp->tm_isdst = 1; 1590 t = time2(tmp, funcp, offset, &okay); 1591#ifdef PCTS 1592 /* 1593 ** PCTS code courtesy Grant Sullivan (grant@osf.org). 1594 */ 1595 if (okay) 1596 return t; 1597 if (tmp->tm_isdst < 0) 1598 tmp->tm_isdst = 0; /* reset to std and try again */ 1599#endif /* defined PCTS */ 1600#ifndef PCTS 1601 if (okay || tmp->tm_isdst < 0) 1602 return t; 1603#endif /* !defined PCTS */ 1604 /* 1605 ** We're supposed to assume that somebody took a time of one type 1606 ** and did some math on it that yielded a "struct tm" that's bad. 1607 ** We try to divine the type they started from and adjust to the 1608 ** type they need. 1609 */ 1610 /* 1611 ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's. 1612 */ 1613 sp = (const struct state *) (((void *) funcp == (void *) localsub) ? 1614 lclptr : gmtptr); 1615#ifdef ALL_STATE 1616 if (sp == NULL) 1617 return WRONG; 1618#endif /* defined ALL_STATE */ 1619 for (samei = sp->typecnt - 1; samei >= 0; --samei) { 1620 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) 1621 continue; 1622 for (otheri = sp->typecnt - 1; otheri >= 0; --otheri) { 1623 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) 1624 continue; 1625 tmp->tm_sec += (int)(sp->ttis[otheri].tt_gmtoff - 1626 sp->ttis[samei].tt_gmtoff); 1627 tmp->tm_isdst = !tmp->tm_isdst; 1628 t = time2(tmp, funcp, offset, &okay); 1629 if (okay) 1630 return t; 1631 tmp->tm_sec -= (int)(sp->ttis[otheri].tt_gmtoff - 1632 sp->ttis[samei].tt_gmtoff); 1633 tmp->tm_isdst = !tmp->tm_isdst; 1634 } 1635 } 1636 return WRONG; 1637} 1638 1639time_t 1640mktime(tmp) 1641struct tm * const tmp; 1642{ 1643 time_t result; 1644 1645 rwlock_wrlock(&lcl_lock); 1646 tzset_unlocked(); 1647 result = time1(tmp, localsub, 0L); 1648 rwlock_unlock(&lcl_lock); 1649 return (result); 1650} 1651 1652#ifdef STD_INSPIRED 1653 1654time_t 1655timelocal(tmp) 1656struct tm * const tmp; 1657{ 1658 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 1659 return mktime(tmp); 1660} 1661 1662time_t 1663timegm(tmp) 1664struct tm * const tmp; 1665{ 1666 tmp->tm_isdst = 0; 1667 return time1(tmp, gmtsub, 0L); 1668} 1669 1670time_t 1671timeoff(tmp, offset) 1672struct tm * const tmp; 1673const long offset; 1674{ 1675 tmp->tm_isdst = 0; 1676 return time1(tmp, gmtsub, offset); 1677} 1678 1679#endif /* defined STD_INSPIRED */ 1680 1681#ifdef CMUCS 1682 1683/* 1684** The following is supplied for compatibility with 1685** previous versions of the CMUCS runtime library. 1686*/ 1687 1688long 1689gtime(tmp) 1690struct tm * const tmp; 1691{ 1692 const time_t t = mktime(tmp); 1693 1694 if (t == WRONG) 1695 return -1; 1696 return t; 1697} 1698 1699#endif /* defined CMUCS */ 1700 1701/* 1702** XXX--is the below the right way to conditionalize?? 1703*/ 1704 1705#ifdef STD_INSPIRED 1706 1707/* 1708** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 1709** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which 1710** is not the case if we are accounting for leap seconds. 1711** So, we provide the following conversion routines for use 1712** when exchanging timestamps with POSIX conforming systems. 1713*/ 1714 1715static long 1716leapcorr(timep) 1717time_t * timep; 1718{ 1719 register struct state * sp; 1720 register struct lsinfo * lp; 1721 register int i; 1722 1723 sp = lclptr; 1724 i = sp->leapcnt; 1725 while (--i >= 0) { 1726 lp = &sp->lsis[i]; 1727 if (*timep >= lp->ls_trans) 1728 return lp->ls_corr; 1729 } 1730 return 0; 1731} 1732 1733time_t 1734time2posix(t) 1735time_t t; 1736{ 1737 time_t result; 1738 1739 rwlock_wrlock(&lcl_lock); 1740 tzset_unlocked(); 1741 result = t - leapcorr(&t); 1742 rwlock_unlock(&lcl_lock); 1743 return (result); 1744} 1745 1746time_t 1747posix2time(t) 1748time_t t; 1749{ 1750 time_t x; 1751 time_t y; 1752 1753 rwlock_wrlock(&lcl_lock); 1754 tzset_unlocked(); 1755 /* 1756 ** For a positive leap second hit, the result 1757 ** is not unique. For a negative leap second 1758 ** hit, the corresponding time doesn't exist, 1759 ** so we return an adjacent second. 1760 */ 1761 x = t + leapcorr(&t); 1762 y = x - leapcorr(&x); 1763 if (y < t) { 1764 do { 1765 x++; 1766 y = x - leapcorr(&x); 1767 } while (y < t); 1768 if (t != y) { 1769 rwlock_unlock(&lcl_lock); 1770 return x - 1; 1771 } 1772 } else if (y > t) { 1773 do { 1774 --x; 1775 y = x - leapcorr(&x); 1776 } while (y > t); 1777 if (t != y) { 1778 rwlock_unlock(&lcl_lock); 1779 return x + 1; 1780 } 1781 } 1782 rwlock_unlock(&lcl_lock); 1783 return x; 1784} 1785 1786#endif /* defined STD_INSPIRED */ 1787