localtime.c revision 177824
1/* 2** This file is in the public domain, so clarified as of 3** 1996-06-05 by Arthur David Olson (arthur_david_olson@nih.gov). 4*/ 5 6#include <sys/cdefs.h> 7#ifndef lint 8#ifndef NOID 9static char elsieid[] __unused = "@(#)localtime.c 7.78"; 10#endif /* !defined NOID */ 11#endif /* !defined lint */ 12__FBSDID("$FreeBSD: head/lib/libc/stdtime/localtime.c 177824 2008-04-01 06:56:11Z davidxu $"); 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#define _RWLOCK_RDLOCK(x) \ 38 do { \ 39 if (__isthreaded) _pthread_rwlock_rdlock(x); \ 40 } while (0) 41 42#define _RWLOCK_WRLOCK(x) \ 43 do { \ 44 if (__isthreaded) _pthread_rwlock_wrlock(x); \ 45 } while (0) 46 47#define _RWLOCK_UNLOCK(x) \ 48 do { \ 49 if (__isthreaded) _pthread_rwlock_unlock(x); \ 50 } while (0) 51 52/* 53** SunOS 4.1.1 headers lack O_BINARY. 54*/ 55 56#ifdef O_BINARY 57#define OPEN_MODE (O_RDONLY | O_BINARY) 58#endif /* defined O_BINARY */ 59#ifndef O_BINARY 60#define OPEN_MODE O_RDONLY 61#endif /* !defined O_BINARY */ 62 63#ifndef WILDABBR 64/* 65** Someone might make incorrect use of a time zone abbreviation: 66** 1. They might reference tzname[0] before calling tzset (explicitly 67** or implicitly). 68** 2. They might reference tzname[1] before calling tzset (explicitly 69** or implicitly). 70** 3. They might reference tzname[1] after setting to a time zone 71** in which Daylight Saving Time is never observed. 72** 4. They might reference tzname[0] after setting to a time zone 73** in which Standard Time is never observed. 74** 5. They might reference tm.TM_ZONE after calling offtime. 75** What's best to do in the above cases is open to debate; 76** for now, we just set things up so that in any of the five cases 77** WILDABBR is used. Another possibility: initialize tzname[0] to the 78** string "tzname[0] used before set", and similarly for the other cases. 79** And another: initialize tzname[0] to "ERA", with an explanation in the 80** manual page of what this "time zone abbreviation" means (doing this so 81** that tzname[0] has the "normal" length of three characters). 82*/ 83#define WILDABBR " " 84#endif /* !defined WILDABBR */ 85 86static char wildabbr[] = "WILDABBR"; 87 88/* 89 * In June 2004 it was decided UTC was a more appropriate default time 90 * zone than GMT. 91 */ 92 93static const char gmt[] = "UTC"; 94 95/* 96** The DST rules to use if TZ has no rules and we can't load TZDEFRULES. 97** We default to US rules as of 1999-08-17. 98** POSIX 1003.1 section 8.1.1 says that the default DST rules are 99** implementation dependent; for historical reasons, US rules are a 100** common default. 101*/ 102#ifndef TZDEFRULESTRING 103#define TZDEFRULESTRING ",M4.1.0,M10.5.0" 104#endif /* !defined TZDEFDST */ 105 106struct ttinfo { /* time type information */ 107 long tt_gmtoff; /* UTC offset in seconds */ 108 int tt_isdst; /* used to set tm_isdst */ 109 int tt_abbrind; /* abbreviation list index */ 110 int tt_ttisstd; /* TRUE if transition is std time */ 111 int tt_ttisgmt; /* TRUE if transition is UTC */ 112}; 113 114struct lsinfo { /* leap second information */ 115 time_t ls_trans; /* transition time */ 116 long ls_corr; /* correction to apply */ 117}; 118 119#define BIGGEST(a, b) (((a) > (b)) ? (a) : (b)) 120 121#ifdef TZNAME_MAX 122#define MY_TZNAME_MAX TZNAME_MAX 123#endif /* defined TZNAME_MAX */ 124#ifndef TZNAME_MAX 125#define MY_TZNAME_MAX 255 126#endif /* !defined TZNAME_MAX */ 127 128struct state { 129 int leapcnt; 130 int timecnt; 131 int typecnt; 132 int charcnt; 133 time_t ats[TZ_MAX_TIMES]; 134 unsigned char types[TZ_MAX_TIMES]; 135 struct ttinfo ttis[TZ_MAX_TYPES]; 136 char chars[BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt), 137 (2 * (MY_TZNAME_MAX + 1)))]; 138 struct lsinfo lsis[TZ_MAX_LEAPS]; 139}; 140 141struct rule { 142 int r_type; /* type of rule--see below */ 143 int r_day; /* day number of rule */ 144 int r_week; /* week number of rule */ 145 int r_mon; /* month number of rule */ 146 long r_time; /* transition time of rule */ 147}; 148 149#define JULIAN_DAY 0 /* Jn - Julian day */ 150#define DAY_OF_YEAR 1 /* n - day of year */ 151#define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */ 152 153/* 154** Prototypes for static functions. 155*/ 156 157static long detzcode(const char * codep); 158static const char * getzname(const char * strp); 159static const char * getnum(const char * strp, int * nump, int min, 160 int max); 161static const char * getsecs(const char * strp, long * secsp); 162static const char * getoffset(const char * strp, long * offsetp); 163static const char * getrule(const char * strp, struct rule * rulep); 164static void gmtload(struct state * sp); 165static void gmtsub(const time_t * timep, long offset, 166 struct tm * tmp); 167static void localsub(const time_t * timep, long offset, 168 struct tm * tmp); 169static int increment_overflow(int * number, int delta); 170static int normalize_overflow(int * tensptr, int * unitsptr, 171 int base); 172static void settzname(void); 173static time_t time1(struct tm * tmp, 174 void(*funcp) (const time_t *, 175 long, struct tm *), 176 long offset); 177static time_t time2(struct tm *tmp, 178 void(*funcp) (const time_t *, 179 long, struct tm*), 180 long offset, int * okayp); 181static time_t time2sub(struct tm *tmp, 182 void(*funcp) (const time_t *, 183 long, struct tm*), 184 long offset, int * okayp, int do_norm_secs); 185static void timesub(const time_t * timep, long offset, 186 const struct state * sp, struct tm * tmp); 187static int tmcomp(const struct tm * atmp, 188 const struct tm * btmp); 189static time_t transtime(time_t janfirst, int year, 190 const struct rule * rulep, long offset); 191static int tzload(const char * name, struct state * sp); 192static int tzparse(const char * name, struct state * sp, 193 int lastditch); 194 195#ifdef ALL_STATE 196static struct state * lclptr; 197static struct state * gmtptr; 198#endif /* defined ALL_STATE */ 199 200#ifndef ALL_STATE 201static struct state lclmem; 202static struct state gmtmem; 203#define lclptr (&lclmem) 204#define gmtptr (&gmtmem) 205#endif /* State Farm */ 206 207#ifndef TZ_STRLEN_MAX 208#define TZ_STRLEN_MAX 255 209#endif /* !defined TZ_STRLEN_MAX */ 210 211static char lcl_TZname[TZ_STRLEN_MAX + 1]; 212static int lcl_is_set; 213static int gmt_is_set; 214static pthread_rwlock_t lcl_rwlock = PTHREAD_RWLOCK_INITIALIZER; 215static pthread_mutex_t gmt_mutex = PTHREAD_MUTEX_INITIALIZER; 216 217char * tzname[2] = { 218 wildabbr, 219 wildabbr 220}; 221 222/* 223** Section 4.12.3 of X3.159-1989 requires that 224** Except for the strftime function, these functions [asctime, 225** ctime, gmtime, localtime] return values in one of two static 226** objects: a broken-down time structure and an array of char. 227** Thanks to Paul Eggert (eggert@twinsun.com) for noting this. 228*/ 229 230static struct tm tm; 231 232#ifdef USG_COMPAT 233time_t timezone = 0; 234int daylight = 0; 235#endif /* defined USG_COMPAT */ 236 237#ifdef ALTZONE 238time_t altzone = 0; 239#endif /* defined ALTZONE */ 240 241static long 242detzcode(codep) 243const char * const codep; 244{ 245 long result; 246 int i; 247 248 result = (codep[0] & 0x80) ? ~0L : 0L; 249 for (i = 0; i < 4; ++i) 250 result = (result << 8) | (codep[i] & 0xff); 251 return result; 252} 253 254static void 255settzname(void) 256{ 257 struct state * sp = lclptr; 258 int i; 259 260 tzname[0] = wildabbr; 261 tzname[1] = wildabbr; 262#ifdef USG_COMPAT 263 daylight = 0; 264 timezone = 0; 265#endif /* defined USG_COMPAT */ 266#ifdef ALTZONE 267 altzone = 0; 268#endif /* defined ALTZONE */ 269#ifdef ALL_STATE 270 if (sp == NULL) { 271 tzname[0] = tzname[1] = gmt; 272 return; 273 } 274#endif /* defined ALL_STATE */ 275 for (i = 0; i < sp->typecnt; ++i) { 276 const struct ttinfo * const ttisp = &sp->ttis[i]; 277 278 tzname[ttisp->tt_isdst] = 279 &sp->chars[ttisp->tt_abbrind]; 280#ifdef USG_COMPAT 281 if (ttisp->tt_isdst) 282 daylight = 1; 283 if (i == 0 || !ttisp->tt_isdst) 284 timezone = -(ttisp->tt_gmtoff); 285#endif /* defined USG_COMPAT */ 286#ifdef ALTZONE 287 if (i == 0 || ttisp->tt_isdst) 288 altzone = -(ttisp->tt_gmtoff); 289#endif /* defined ALTZONE */ 290 } 291 /* 292 ** And to get the latest zone names into tzname. . . 293 */ 294 for (i = 0; i < sp->timecnt; ++i) { 295 const struct ttinfo * const ttisp = 296 &sp->ttis[ 297 sp->types[i]]; 298 299 tzname[ttisp->tt_isdst] = 300 &sp->chars[ttisp->tt_abbrind]; 301 } 302} 303 304static int 305tzload(name, sp) 306const char * name; 307struct state * const sp; 308{ 309 const char * p; 310 int i; 311 int fid; 312 313 /* XXX The following is from OpenBSD, and I'm not sure it is correct */ 314 if (name != NULL && issetugid() != 0) 315 if ((name[0] == ':' && name[1] == '/') || 316 name[0] == '/' || strchr(name, '.')) 317 name = NULL; 318 if (name == NULL && (name = TZDEFAULT) == NULL) 319 return -1; 320 { 321 int doaccess; 322 struct stat stab; 323 /* 324 ** Section 4.9.1 of the C standard says that 325 ** "FILENAME_MAX expands to an integral constant expression 326 ** that is the size needed for an array of char large enough 327 ** to hold the longest file name string that the implementation 328 ** guarantees can be opened." 329 */ 330 char fullname[FILENAME_MAX + 1]; 331 332 if (name[0] == ':') 333 ++name; 334 doaccess = name[0] == '/'; 335 if (!doaccess) { 336 if ((p = TZDIR) == NULL) 337 return -1; 338 if ((strlen(p) + 1 + strlen(name) + 1) >= sizeof fullname) 339 return -1; 340 (void) strcpy(fullname, p); 341 (void) strcat(fullname, "/"); 342 (void) strcat(fullname, name); 343 /* 344 ** Set doaccess if '.' (as in "../") shows up in name. 345 */ 346 if (strchr(name, '.') != NULL) 347 doaccess = TRUE; 348 name = fullname; 349 } 350 if (doaccess && access(name, R_OK) != 0) 351 return -1; 352 if ((fid = _open(name, OPEN_MODE)) == -1) 353 return -1; 354 if ((_fstat(fid, &stab) < 0) || !S_ISREG(stab.st_mode)) { 355 _close(fid); 356 return -1; 357 } 358 } 359 { 360 struct tzhead * tzhp; 361 union { 362 struct tzhead tzhead; 363 char buf[sizeof *sp + sizeof *tzhp]; 364 } u; 365 int ttisstdcnt; 366 int ttisgmtcnt; 367 368 i = _read(fid, u.buf, sizeof u.buf); 369 if (_close(fid) != 0) 370 return -1; 371 ttisstdcnt = (int) detzcode(u.tzhead.tzh_ttisstdcnt); 372 ttisgmtcnt = (int) detzcode(u.tzhead.tzh_ttisgmtcnt); 373 sp->leapcnt = (int) detzcode(u.tzhead.tzh_leapcnt); 374 sp->timecnt = (int) detzcode(u.tzhead.tzh_timecnt); 375 sp->typecnt = (int) detzcode(u.tzhead.tzh_typecnt); 376 sp->charcnt = (int) detzcode(u.tzhead.tzh_charcnt); 377 p = u.tzhead.tzh_charcnt + sizeof u.tzhead.tzh_charcnt; 378 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS || 379 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES || 380 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES || 381 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS || 382 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) || 383 (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0)) 384 return -1; 385 if (i - (p - u.buf) < sp->timecnt * 4 + /* ats */ 386 sp->timecnt + /* types */ 387 sp->typecnt * (4 + 2) + /* ttinfos */ 388 sp->charcnt + /* chars */ 389 sp->leapcnt * (4 + 4) + /* lsinfos */ 390 ttisstdcnt + /* ttisstds */ 391 ttisgmtcnt) /* ttisgmts */ 392 return -1; 393 for (i = 0; i < sp->timecnt; ++i) { 394 sp->ats[i] = detzcode(p); 395 p += 4; 396 } 397 for (i = 0; i < sp->timecnt; ++i) { 398 sp->types[i] = (unsigned char) *p++; 399 if (sp->types[i] >= sp->typecnt) 400 return -1; 401 } 402 for (i = 0; i < sp->typecnt; ++i) { 403 struct ttinfo * ttisp; 404 405 ttisp = &sp->ttis[i]; 406 ttisp->tt_gmtoff = detzcode(p); 407 p += 4; 408 ttisp->tt_isdst = (unsigned char) *p++; 409 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1) 410 return -1; 411 ttisp->tt_abbrind = (unsigned char) *p++; 412 if (ttisp->tt_abbrind < 0 || 413 ttisp->tt_abbrind > sp->charcnt) 414 return -1; 415 } 416 for (i = 0; i < sp->charcnt; ++i) 417 sp->chars[i] = *p++; 418 sp->chars[i] = '\0'; /* ensure '\0' at end */ 419 for (i = 0; i < sp->leapcnt; ++i) { 420 struct lsinfo * lsisp; 421 422 lsisp = &sp->lsis[i]; 423 lsisp->ls_trans = detzcode(p); 424 p += 4; 425 lsisp->ls_corr = detzcode(p); 426 p += 4; 427 } 428 for (i = 0; i < sp->typecnt; ++i) { 429 struct ttinfo * ttisp; 430 431 ttisp = &sp->ttis[i]; 432 if (ttisstdcnt == 0) 433 ttisp->tt_ttisstd = FALSE; 434 else { 435 ttisp->tt_ttisstd = *p++; 436 if (ttisp->tt_ttisstd != TRUE && 437 ttisp->tt_ttisstd != FALSE) 438 return -1; 439 } 440 } 441 for (i = 0; i < sp->typecnt; ++i) { 442 struct ttinfo * ttisp; 443 444 ttisp = &sp->ttis[i]; 445 if (ttisgmtcnt == 0) 446 ttisp->tt_ttisgmt = FALSE; 447 else { 448 ttisp->tt_ttisgmt = *p++; 449 if (ttisp->tt_ttisgmt != TRUE && 450 ttisp->tt_ttisgmt != FALSE) 451 return -1; 452 } 453 } 454 } 455 return 0; 456} 457 458static const int mon_lengths[2][MONSPERYEAR] = { 459 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, 460 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } 461}; 462 463static const int year_lengths[2] = { 464 DAYSPERNYEAR, DAYSPERLYEAR 465}; 466 467/* 468** Given a pointer into a time zone string, scan until a character that is not 469** a valid character in a zone name is found. Return a pointer to that 470** character. 471*/ 472 473static const char * 474getzname(strp) 475const char * strp; 476{ 477 char c; 478 479 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && 480 c != '+') 481 ++strp; 482 return strp; 483} 484 485/* 486** Given a pointer into a time zone string, extract a number from that string. 487** Check that the number is within a specified range; if it is not, return 488** NULL. 489** Otherwise, return a pointer to the first character not part of the number. 490*/ 491 492static const char * 493getnum(strp, nump, min, max) 494const char * strp; 495int * const nump; 496const int min; 497const int max; 498{ 499 char c; 500 int num; 501 502 if (strp == NULL || !is_digit(c = *strp)) 503 return NULL; 504 num = 0; 505 do { 506 num = num * 10 + (c - '0'); 507 if (num > max) 508 return NULL; /* illegal value */ 509 c = *++strp; 510 } while (is_digit(c)); 511 if (num < min) 512 return NULL; /* illegal value */ 513 *nump = num; 514 return strp; 515} 516 517/* 518** Given a pointer into a time zone string, extract a number of seconds, 519** in hh[:mm[:ss]] form, from the string. 520** If any error occurs, return NULL. 521** Otherwise, return a pointer to the first character not part of the number 522** of seconds. 523*/ 524 525static const char * 526getsecs(strp, secsp) 527const char * strp; 528long * const secsp; 529{ 530 int num; 531 532 /* 533 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like 534 ** "M10.4.6/26", which does not conform to Posix, 535 ** but which specifies the equivalent of 536 ** ``02:00 on the first Sunday on or after 23 Oct''. 537 */ 538 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); 539 if (strp == NULL) 540 return NULL; 541 *secsp = num * (long) SECSPERHOUR; 542 if (*strp == ':') { 543 ++strp; 544 strp = getnum(strp, &num, 0, MINSPERHOUR - 1); 545 if (strp == NULL) 546 return NULL; 547 *secsp += num * SECSPERMIN; 548 if (*strp == ':') { 549 ++strp; 550 /* `SECSPERMIN' allows for leap seconds. */ 551 strp = getnum(strp, &num, 0, SECSPERMIN); 552 if (strp == NULL) 553 return NULL; 554 *secsp += num; 555 } 556 } 557 return strp; 558} 559 560/* 561** Given a pointer into a time zone string, extract an offset, in 562** [+-]hh[:mm[:ss]] form, from the string. 563** If any error occurs, return NULL. 564** Otherwise, return a pointer to the first character not part of the time. 565*/ 566 567static const char * 568getoffset(strp, offsetp) 569const char * strp; 570long * const offsetp; 571{ 572 int neg = 0; 573 574 if (*strp == '-') { 575 neg = 1; 576 ++strp; 577 } else if (*strp == '+') 578 ++strp; 579 strp = getsecs(strp, offsetp); 580 if (strp == NULL) 581 return NULL; /* illegal time */ 582 if (neg) 583 *offsetp = -*offsetp; 584 return strp; 585} 586 587/* 588** Given a pointer into a time zone string, extract a rule in the form 589** date[/time]. See POSIX section 8 for the format of "date" and "time". 590** If a valid rule is not found, return NULL. 591** Otherwise, return a pointer to the first character not part of the rule. 592*/ 593 594static const char * 595getrule(strp, rulep) 596const char * strp; 597struct rule * const rulep; 598{ 599 if (*strp == 'J') { 600 /* 601 ** Julian day. 602 */ 603 rulep->r_type = JULIAN_DAY; 604 ++strp; 605 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); 606 } else if (*strp == 'M') { 607 /* 608 ** Month, week, day. 609 */ 610 rulep->r_type = MONTH_NTH_DAY_OF_WEEK; 611 ++strp; 612 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); 613 if (strp == NULL) 614 return NULL; 615 if (*strp++ != '.') 616 return NULL; 617 strp = getnum(strp, &rulep->r_week, 1, 5); 618 if (strp == NULL) 619 return NULL; 620 if (*strp++ != '.') 621 return NULL; 622 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); 623 } else if (is_digit(*strp)) { 624 /* 625 ** Day of year. 626 */ 627 rulep->r_type = DAY_OF_YEAR; 628 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); 629 } else return NULL; /* invalid format */ 630 if (strp == NULL) 631 return NULL; 632 if (*strp == '/') { 633 /* 634 ** Time specified. 635 */ 636 ++strp; 637 strp = getsecs(strp, &rulep->r_time); 638 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ 639 return strp; 640} 641 642/* 643** Given the Epoch-relative time of January 1, 00:00:00 UTC, in a year, the 644** year, a rule, and the offset from UTC at the time that rule takes effect, 645** calculate the Epoch-relative time that rule takes effect. 646*/ 647 648static time_t 649transtime(janfirst, year, rulep, offset) 650const time_t janfirst; 651const int year; 652const struct rule * const rulep; 653const long offset; 654{ 655 int leapyear; 656 time_t value; 657 int i; 658 int d, m1, yy0, yy1, yy2, dow; 659 660 INITIALIZE(value); 661 leapyear = isleap(year); 662 switch (rulep->r_type) { 663 664 case JULIAN_DAY: 665 /* 666 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap 667 ** years. 668 ** In non-leap years, or if the day number is 59 or less, just 669 ** add SECSPERDAY times the day number-1 to the time of 670 ** January 1, midnight, to get the day. 671 */ 672 value = janfirst + (rulep->r_day - 1) * SECSPERDAY; 673 if (leapyear && rulep->r_day >= 60) 674 value += SECSPERDAY; 675 break; 676 677 case DAY_OF_YEAR: 678 /* 679 ** n - day of year. 680 ** Just add SECSPERDAY times the day number to the time of 681 ** January 1, midnight, to get the day. 682 */ 683 value = janfirst + rulep->r_day * SECSPERDAY; 684 break; 685 686 case MONTH_NTH_DAY_OF_WEEK: 687 /* 688 ** Mm.n.d - nth "dth day" of month m. 689 */ 690 value = janfirst; 691 for (i = 0; i < rulep->r_mon - 1; ++i) 692 value += mon_lengths[leapyear][i] * SECSPERDAY; 693 694 /* 695 ** Use Zeller's Congruence to get day-of-week of first day of 696 ** month. 697 */ 698 m1 = (rulep->r_mon + 9) % 12 + 1; 699 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; 700 yy1 = yy0 / 100; 701 yy2 = yy0 % 100; 702 dow = ((26 * m1 - 2) / 10 + 703 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; 704 if (dow < 0) 705 dow += DAYSPERWEEK; 706 707 /* 708 ** "dow" is the day-of-week of the first day of the month. Get 709 ** the day-of-month (zero-origin) of the first "dow" day of the 710 ** month. 711 */ 712 d = rulep->r_day - dow; 713 if (d < 0) 714 d += DAYSPERWEEK; 715 for (i = 1; i < rulep->r_week; ++i) { 716 if (d + DAYSPERWEEK >= 717 mon_lengths[leapyear][rulep->r_mon - 1]) 718 break; 719 d += DAYSPERWEEK; 720 } 721 722 /* 723 ** "d" is the day-of-month (zero-origin) of the day we want. 724 */ 725 value += d * SECSPERDAY; 726 break; 727 } 728 729 /* 730 ** "value" is the Epoch-relative time of 00:00:00 UTC on the day in 731 ** question. To get the Epoch-relative time of the specified local 732 ** time on that day, add the transition time and the current offset 733 ** from UTC. 734 */ 735 return value + rulep->r_time + offset; 736} 737 738/* 739** Given a POSIX section 8-style TZ string, fill in the rule tables as 740** appropriate. 741*/ 742 743static int 744tzparse(name, sp, lastditch) 745const char * name; 746struct state * const sp; 747const int lastditch; 748{ 749 const char * stdname; 750 const char * dstname; 751 size_t stdlen; 752 size_t dstlen; 753 long stdoffset; 754 long dstoffset; 755 time_t * atp; 756 unsigned char * typep; 757 char * cp; 758 int load_result; 759 760 INITIALIZE(dstname); 761 stdname = name; 762 if (lastditch) { 763 stdlen = strlen(name); /* length of standard zone name */ 764 name += stdlen; 765 if (stdlen >= sizeof sp->chars) 766 stdlen = (sizeof sp->chars) - 1; 767 stdoffset = 0; 768 } else { 769 name = getzname(name); 770 stdlen = name - stdname; 771 if (stdlen < 3) 772 return -1; 773 if (*name == '\0') 774 return -1; /* was "stdoffset = 0;" */ 775 else { 776 name = getoffset(name, &stdoffset); 777 if (name == NULL) 778 return -1; 779 } 780 } 781 load_result = tzload(TZDEFRULES, sp); 782 if (load_result != 0) 783 sp->leapcnt = 0; /* so, we're off a little */ 784 if (*name != '\0') { 785 dstname = name; 786 name = getzname(name); 787 dstlen = name - dstname; /* length of DST zone name */ 788 if (dstlen < 3) 789 return -1; 790 if (*name != '\0' && *name != ',' && *name != ';') { 791 name = getoffset(name, &dstoffset); 792 if (name == NULL) 793 return -1; 794 } else dstoffset = stdoffset - SECSPERHOUR; 795 if (*name == '\0' && load_result != 0) 796 name = TZDEFRULESTRING; 797 if (*name == ',' || *name == ';') { 798 struct rule start; 799 struct rule end; 800 int year; 801 time_t janfirst; 802 time_t starttime; 803 time_t endtime; 804 805 ++name; 806 if ((name = getrule(name, &start)) == NULL) 807 return -1; 808 if (*name++ != ',') 809 return -1; 810 if ((name = getrule(name, &end)) == NULL) 811 return -1; 812 if (*name != '\0') 813 return -1; 814 sp->typecnt = 2; /* standard time and DST */ 815 /* 816 ** Two transitions per year, from EPOCH_YEAR to 2037. 817 */ 818 sp->timecnt = 2 * (2037 - EPOCH_YEAR + 1); 819 if (sp->timecnt > TZ_MAX_TIMES) 820 return -1; 821 sp->ttis[0].tt_gmtoff = -dstoffset; 822 sp->ttis[0].tt_isdst = 1; 823 sp->ttis[0].tt_abbrind = stdlen + 1; 824 sp->ttis[1].tt_gmtoff = -stdoffset; 825 sp->ttis[1].tt_isdst = 0; 826 sp->ttis[1].tt_abbrind = 0; 827 atp = sp->ats; 828 typep = sp->types; 829 janfirst = 0; 830 for (year = EPOCH_YEAR; year <= 2037; ++year) { 831 starttime = transtime(janfirst, year, &start, 832 stdoffset); 833 endtime = transtime(janfirst, year, &end, 834 dstoffset); 835 if (starttime > endtime) { 836 *atp++ = endtime; 837 *typep++ = 1; /* DST ends */ 838 *atp++ = starttime; 839 *typep++ = 0; /* DST begins */ 840 } else { 841 *atp++ = starttime; 842 *typep++ = 0; /* DST begins */ 843 *atp++ = endtime; 844 *typep++ = 1; /* DST ends */ 845 } 846 janfirst += year_lengths[isleap(year)] * 847 SECSPERDAY; 848 } 849 } else { 850 long theirstdoffset; 851 long theirdstoffset; 852 long theiroffset; 853 int isdst; 854 int i; 855 int j; 856 857 if (*name != '\0') 858 return -1; 859 /* 860 ** Initial values of theirstdoffset and theirdstoffset. 861 */ 862 theirstdoffset = 0; 863 for (i = 0; i < sp->timecnt; ++i) { 864 j = sp->types[i]; 865 if (!sp->ttis[j].tt_isdst) { 866 theirstdoffset = 867 -sp->ttis[j].tt_gmtoff; 868 break; 869 } 870 } 871 theirdstoffset = 0; 872 for (i = 0; i < sp->timecnt; ++i) { 873 j = sp->types[i]; 874 if (sp->ttis[j].tt_isdst) { 875 theirdstoffset = 876 -sp->ttis[j].tt_gmtoff; 877 break; 878 } 879 } 880 /* 881 ** Initially we're assumed to be in standard time. 882 */ 883 isdst = FALSE; 884 theiroffset = theirstdoffset; 885 /* 886 ** Now juggle transition times and types 887 ** tracking offsets as you do. 888 */ 889 for (i = 0; i < sp->timecnt; ++i) { 890 j = sp->types[i]; 891 sp->types[i] = sp->ttis[j].tt_isdst; 892 if (sp->ttis[j].tt_ttisgmt) { 893 /* No adjustment to transition time */ 894 } else { 895 /* 896 ** If summer time is in effect, and the 897 ** transition time was not specified as 898 ** standard time, add the summer time 899 ** offset to the transition time; 900 ** otherwise, add the standard time 901 ** offset to the transition time. 902 */ 903 /* 904 ** Transitions from DST to DDST 905 ** will effectively disappear since 906 ** POSIX provides for only one DST 907 ** offset. 908 */ 909 if (isdst && !sp->ttis[j].tt_ttisstd) { 910 sp->ats[i] += dstoffset - 911 theirdstoffset; 912 } else { 913 sp->ats[i] += stdoffset - 914 theirstdoffset; 915 } 916 } 917 theiroffset = -sp->ttis[j].tt_gmtoff; 918 if (sp->ttis[j].tt_isdst) 919 theirdstoffset = theiroffset; 920 else theirstdoffset = theiroffset; 921 } 922 /* 923 ** Finally, fill in ttis. 924 ** ttisstd and ttisgmt need not be handled. 925 */ 926 sp->ttis[0].tt_gmtoff = -stdoffset; 927 sp->ttis[0].tt_isdst = FALSE; 928 sp->ttis[0].tt_abbrind = 0; 929 sp->ttis[1].tt_gmtoff = -dstoffset; 930 sp->ttis[1].tt_isdst = TRUE; 931 sp->ttis[1].tt_abbrind = stdlen + 1; 932 sp->typecnt = 2; 933 } 934 } else { 935 dstlen = 0; 936 sp->typecnt = 1; /* only standard time */ 937 sp->timecnt = 0; 938 sp->ttis[0].tt_gmtoff = -stdoffset; 939 sp->ttis[0].tt_isdst = 0; 940 sp->ttis[0].tt_abbrind = 0; 941 } 942 sp->charcnt = stdlen + 1; 943 if (dstlen != 0) 944 sp->charcnt += dstlen + 1; 945 if ((size_t) sp->charcnt > sizeof sp->chars) 946 return -1; 947 cp = sp->chars; 948 (void) strncpy(cp, stdname, stdlen); 949 cp += stdlen; 950 *cp++ = '\0'; 951 if (dstlen != 0) { 952 (void) strncpy(cp, dstname, dstlen); 953 *(cp + dstlen) = '\0'; 954 } 955 return 0; 956} 957 958static void 959gmtload(sp) 960struct state * const sp; 961{ 962 if (tzload(gmt, sp) != 0) 963 (void) tzparse(gmt, sp, TRUE); 964} 965 966static void 967tzsetwall_basic(int rdlocked) 968{ 969 if (!rdlocked) 970 _RWLOCK_RDLOCK(&lcl_rwlock); 971 if (lcl_is_set < 0) { 972 if (!rdlocked) 973 _RWLOCK_UNLOCK(&lcl_rwlock); 974 return; 975 } 976 _RWLOCK_UNLOCK(&lcl_rwlock); 977 978 _RWLOCK_WRLOCK(&lcl_rwlock); 979 lcl_is_set = -1; 980 981#ifdef ALL_STATE 982 if (lclptr == NULL) { 983 lclptr = (struct state *) malloc(sizeof *lclptr); 984 if (lclptr == NULL) { 985 settzname(); /* all we can do */ 986 _RWLOCK_UNLOCK(&lcl_rwlock); 987 if (rdlocked) 988 _RWLOCK_RDLOCK(&lcl_rwlock); 989 return; 990 } 991 } 992#endif /* defined ALL_STATE */ 993 if (tzload((char *) NULL, lclptr) != 0) 994 gmtload(lclptr); 995 settzname(); 996 _RWLOCK_UNLOCK(&lcl_rwlock); 997 998 if (rdlocked) 999 _RWLOCK_RDLOCK(&lcl_rwlock); 1000} 1001 1002void 1003tzsetwall(void) 1004{ 1005 tzsetwall_basic(0); 1006} 1007 1008static void 1009tzset_basic(int rdlocked) 1010{ 1011 const char * name; 1012 1013 name = getenv("TZ"); 1014 if (name == NULL) { 1015 tzsetwall_basic(rdlocked); 1016 return; 1017 } 1018 1019 if (!rdlocked) 1020 _RWLOCK_RDLOCK(&lcl_rwlock); 1021 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) { 1022 if (!rdlocked) 1023 _RWLOCK_UNLOCK(&lcl_rwlock); 1024 return; 1025 } 1026 _RWLOCK_UNLOCK(&lcl_rwlock); 1027 1028 _RWLOCK_WRLOCK(&lcl_rwlock); 1029 lcl_is_set = strlen(name) < sizeof lcl_TZname; 1030 if (lcl_is_set) 1031 (void) strcpy(lcl_TZname, name); 1032 1033#ifdef ALL_STATE 1034 if (lclptr == NULL) { 1035 lclptr = (struct state *) malloc(sizeof *lclptr); 1036 if (lclptr == NULL) { 1037 settzname(); /* all we can do */ 1038 _RWLOCK_UNLOCK(&lcl_rwlock); 1039 if (rdlocked) 1040 _RWLOCK_RDLOCK(&lcl_rwlock); 1041 return; 1042 } 1043 } 1044#endif /* defined ALL_STATE */ 1045 if (*name == '\0') { 1046 /* 1047 ** User wants it fast rather than right. 1048 */ 1049 lclptr->leapcnt = 0; /* so, we're off a little */ 1050 lclptr->timecnt = 0; 1051 lclptr->typecnt = 0; 1052 lclptr->ttis[0].tt_isdst = 0; 1053 lclptr->ttis[0].tt_gmtoff = 0; 1054 lclptr->ttis[0].tt_abbrind = 0; 1055 (void) strcpy(lclptr->chars, gmt); 1056 } else if (tzload(name, lclptr) != 0) 1057 if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0) 1058 (void) gmtload(lclptr); 1059 settzname(); 1060 _RWLOCK_UNLOCK(&lcl_rwlock); 1061 1062 if (rdlocked) 1063 _RWLOCK_RDLOCK(&lcl_rwlock); 1064} 1065 1066void 1067tzset(void) 1068{ 1069 tzset_basic(0); 1070} 1071 1072/* 1073** The easy way to behave "as if no library function calls" localtime 1074** is to not call it--so we drop its guts into "localsub", which can be 1075** freely called. (And no, the PANS doesn't require the above behavior-- 1076** but it *is* desirable.) 1077** 1078** The unused offset argument is for the benefit of mktime variants. 1079*/ 1080 1081/*ARGSUSED*/ 1082static void 1083localsub(timep, offset, tmp) 1084const time_t * const timep; 1085const long offset; 1086struct tm * const tmp; 1087{ 1088 struct state * sp; 1089 const struct ttinfo * ttisp; 1090 int i; 1091 const time_t t = *timep; 1092 1093 sp = lclptr; 1094#ifdef ALL_STATE 1095 if (sp == NULL) { 1096 gmtsub(timep, offset, tmp); 1097 return; 1098 } 1099#endif /* defined ALL_STATE */ 1100 if (sp->timecnt == 0 || t < sp->ats[0]) { 1101 i = 0; 1102 while (sp->ttis[i].tt_isdst) 1103 if (++i >= sp->typecnt) { 1104 i = 0; 1105 break; 1106 } 1107 } else { 1108 for (i = 1; i < sp->timecnt; ++i) 1109 if (t < sp->ats[i]) 1110 break; 1111 i = sp->types[i - 1]; 1112 } 1113 ttisp = &sp->ttis[i]; 1114 /* 1115 ** To get (wrong) behavior that's compatible with System V Release 2.0 1116 ** you'd replace the statement below with 1117 ** t += ttisp->tt_gmtoff; 1118 ** timesub(&t, 0L, sp, tmp); 1119 */ 1120 timesub(&t, ttisp->tt_gmtoff, sp, tmp); 1121 tmp->tm_isdst = ttisp->tt_isdst; 1122 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind]; 1123#ifdef TM_ZONE 1124 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind]; 1125#endif /* defined TM_ZONE */ 1126} 1127 1128struct tm * 1129localtime(timep) 1130const time_t * const timep; 1131{ 1132 static pthread_mutex_t localtime_mutex = PTHREAD_MUTEX_INITIALIZER; 1133 static pthread_key_t localtime_key = -1; 1134 struct tm *p_tm; 1135 1136 if (__isthreaded != 0) { 1137 if (localtime_key < 0) { 1138 _pthread_mutex_lock(&localtime_mutex); 1139 if (localtime_key < 0) { 1140 if (_pthread_key_create(&localtime_key, free) < 0) { 1141 _pthread_mutex_unlock(&localtime_mutex); 1142 return(NULL); 1143 } 1144 } 1145 _pthread_mutex_unlock(&localtime_mutex); 1146 } 1147 p_tm = _pthread_getspecific(localtime_key); 1148 if (p_tm == NULL) { 1149 if ((p_tm = (struct tm *)malloc(sizeof(struct tm))) 1150 == NULL) 1151 return(NULL); 1152 _pthread_setspecific(localtime_key, p_tm); 1153 } 1154 _RWLOCK_RDLOCK(&lcl_rwlock); 1155 tzset_basic(1); 1156 localsub(timep, 0L, p_tm); 1157 _RWLOCK_UNLOCK(&lcl_rwlock); 1158 return(p_tm); 1159 } else { 1160 tzset_basic(0); 1161 localsub(timep, 0L, &tm); 1162 return(&tm); 1163 } 1164} 1165 1166/* 1167** Re-entrant version of localtime. 1168*/ 1169 1170struct tm * 1171localtime_r(timep, tm) 1172const time_t * const timep; 1173struct tm * tm; 1174{ 1175 _RWLOCK_RDLOCK(&lcl_rwlock); 1176 tzset_basic(1); 1177 localsub(timep, 0L, tm); 1178 _RWLOCK_UNLOCK(&lcl_rwlock); 1179 return tm; 1180} 1181 1182/* 1183** gmtsub is to gmtime as localsub is to localtime. 1184*/ 1185 1186static void 1187gmtsub(timep, offset, tmp) 1188const time_t * const timep; 1189const long offset; 1190struct tm * const tmp; 1191{ 1192 if (!gmt_is_set) { 1193 _MUTEX_LOCK(&gmt_mutex); 1194 if (!gmt_is_set) { 1195#ifdef ALL_STATE 1196 gmtptr = (struct state *) malloc(sizeof *gmtptr); 1197 if (gmtptr != NULL) 1198#endif /* defined ALL_STATE */ 1199 gmtload(gmtptr); 1200 gmt_is_set = TRUE; 1201 } 1202 _MUTEX_UNLOCK(&gmt_mutex); 1203 } 1204 timesub(timep, offset, gmtptr, tmp); 1205#ifdef TM_ZONE 1206 /* 1207 ** Could get fancy here and deliver something such as 1208 ** "UTC+xxxx" or "UTC-xxxx" if offset is non-zero, 1209 ** but this is no time for a treasure hunt. 1210 */ 1211 if (offset != 0) 1212 tmp->TM_ZONE = wildabbr; 1213 else { 1214#ifdef ALL_STATE 1215 if (gmtptr == NULL) 1216 tmp->TM_ZONE = gmt; 1217 else tmp->TM_ZONE = gmtptr->chars; 1218#endif /* defined ALL_STATE */ 1219#ifndef ALL_STATE 1220 tmp->TM_ZONE = gmtptr->chars; 1221#endif /* State Farm */ 1222 } 1223#endif /* defined TM_ZONE */ 1224} 1225 1226struct tm * 1227gmtime(timep) 1228const time_t * const timep; 1229{ 1230 static pthread_mutex_t gmtime_mutex = PTHREAD_MUTEX_INITIALIZER; 1231 static pthread_key_t gmtime_key = -1; 1232 struct tm *p_tm; 1233 1234 if (__isthreaded != 0) { 1235 if (gmtime_key < 0) { 1236 _pthread_mutex_lock(&gmtime_mutex); 1237 if (gmtime_key < 0) { 1238 if (_pthread_key_create(&gmtime_key, free) < 0) { 1239 _pthread_mutex_unlock(&gmtime_mutex); 1240 return(NULL); 1241 } 1242 } 1243 _pthread_mutex_unlock(&gmtime_mutex); 1244 } 1245 /* 1246 * Changed to follow POSIX.1 threads standard, which 1247 * is what BSD currently has. 1248 */ 1249 if ((p_tm = _pthread_getspecific(gmtime_key)) == NULL) { 1250 if ((p_tm = (struct tm *)malloc(sizeof(struct tm))) 1251 == NULL) { 1252 return(NULL); 1253 } 1254 _pthread_setspecific(gmtime_key, p_tm); 1255 } 1256 gmtsub(timep, 0L, p_tm); 1257 return(p_tm); 1258 } 1259 else { 1260 gmtsub(timep, 0L, &tm); 1261 return(&tm); 1262 } 1263} 1264 1265/* 1266* Re-entrant version of gmtime. 1267*/ 1268 1269struct tm * 1270gmtime_r(timep, tm) 1271const time_t * const timep; 1272struct tm * tm; 1273{ 1274 gmtsub(timep, 0L, tm); 1275 return tm; 1276} 1277 1278#ifdef STD_INSPIRED 1279 1280struct tm * 1281offtime(timep, offset) 1282const time_t * const timep; 1283const long offset; 1284{ 1285 gmtsub(timep, offset, &tm); 1286 return &tm; 1287} 1288 1289#endif /* defined STD_INSPIRED */ 1290 1291static void 1292timesub(timep, offset, sp, tmp) 1293const time_t * const timep; 1294const long offset; 1295const struct state * const sp; 1296struct tm * const tmp; 1297{ 1298 const struct lsinfo * lp; 1299 long days; 1300 long rem; 1301 long y; 1302 int yleap; 1303 const int * ip; 1304 long corr; 1305 int hit; 1306 int i; 1307 1308 corr = 0; 1309 hit = 0; 1310#ifdef ALL_STATE 1311 i = (sp == NULL) ? 0 : sp->leapcnt; 1312#endif /* defined ALL_STATE */ 1313#ifndef ALL_STATE 1314 i = sp->leapcnt; 1315#endif /* State Farm */ 1316 while (--i >= 0) { 1317 lp = &sp->lsis[i]; 1318 if (*timep >= lp->ls_trans) { 1319 if (*timep == lp->ls_trans) { 1320 hit = ((i == 0 && lp->ls_corr > 0) || 1321 lp->ls_corr > sp->lsis[i - 1].ls_corr); 1322 if (hit) 1323 while (i > 0 && 1324 sp->lsis[i].ls_trans == 1325 sp->lsis[i - 1].ls_trans + 1 && 1326 sp->lsis[i].ls_corr == 1327 sp->lsis[i - 1].ls_corr + 1) { 1328 ++hit; 1329 --i; 1330 } 1331 } 1332 corr = lp->ls_corr; 1333 break; 1334 } 1335 } 1336 days = *timep / SECSPERDAY; 1337 rem = *timep % SECSPERDAY; 1338#ifdef mc68k 1339 if (*timep == 0x80000000) { 1340 /* 1341 ** A 3B1 muffs the division on the most negative number. 1342 */ 1343 days = -24855; 1344 rem = -11648; 1345 } 1346#endif /* defined mc68k */ 1347 rem += (offset - corr); 1348 while (rem < 0) { 1349 rem += SECSPERDAY; 1350 --days; 1351 } 1352 while (rem >= SECSPERDAY) { 1353 rem -= SECSPERDAY; 1354 ++days; 1355 } 1356 tmp->tm_hour = (int) (rem / SECSPERHOUR); 1357 rem = rem % SECSPERHOUR; 1358 tmp->tm_min = (int) (rem / SECSPERMIN); 1359 /* 1360 ** A positive leap second requires a special 1361 ** representation. This uses "... ??:59:60" et seq. 1362 */ 1363 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit; 1364 tmp->tm_wday = (int) ((EPOCH_WDAY + days) % DAYSPERWEEK); 1365 if (tmp->tm_wday < 0) 1366 tmp->tm_wday += DAYSPERWEEK; 1367 y = EPOCH_YEAR; 1368#define LEAPS_THRU_END_OF(y) ((y) / 4 - (y) / 100 + (y) / 400) 1369 while (days < 0 || days >= (long) year_lengths[yleap = isleap(y)]) { 1370 long newy; 1371 1372 newy = y + days / DAYSPERNYEAR; 1373 if (days < 0) 1374 --newy; 1375 days -= (newy - y) * DAYSPERNYEAR + 1376 LEAPS_THRU_END_OF(newy - 1) - 1377 LEAPS_THRU_END_OF(y - 1); 1378 y = newy; 1379 } 1380 tmp->tm_year = y - TM_YEAR_BASE; 1381 tmp->tm_yday = (int) days; 1382 ip = mon_lengths[yleap]; 1383 for (tmp->tm_mon = 0; days >= (long) ip[tmp->tm_mon]; ++(tmp->tm_mon)) 1384 days = days - (long) ip[tmp->tm_mon]; 1385 tmp->tm_mday = (int) (days + 1); 1386 tmp->tm_isdst = 0; 1387#ifdef TM_GMTOFF 1388 tmp->TM_GMTOFF = offset; 1389#endif /* defined TM_GMTOFF */ 1390} 1391 1392char * 1393ctime(timep) 1394const time_t * const timep; 1395{ 1396/* 1397** Section 4.12.3.2 of X3.159-1989 requires that 1398** The ctime function converts the calendar time pointed to by timer 1399** to local time in the form of a string. It is equivalent to 1400** asctime(localtime(timer)) 1401*/ 1402 return asctime(localtime(timep)); 1403} 1404 1405char * 1406ctime_r(timep, buf) 1407const time_t * const timep; 1408char * buf; 1409{ 1410 struct tm tm; 1411 1412 return asctime_r(localtime_r(timep, &tm), buf); 1413} 1414 1415/* 1416** Adapted from code provided by Robert Elz, who writes: 1417** The "best" way to do mktime I think is based on an idea of Bob 1418** Kridle's (so its said...) from a long time ago. 1419** [kridle@xinet.com as of 1996-01-16.] 1420** It does a binary search of the time_t space. Since time_t's are 1421** just 32 bits, its a max of 32 iterations (even at 64 bits it 1422** would still be very reasonable). 1423*/ 1424 1425#ifndef WRONG 1426#define WRONG (-1) 1427#endif /* !defined WRONG */ 1428 1429/* 1430** Simplified normalize logic courtesy Paul Eggert (eggert@twinsun.com). 1431*/ 1432 1433static int 1434increment_overflow(number, delta) 1435int * number; 1436int delta; 1437{ 1438 int number0; 1439 1440 number0 = *number; 1441 *number += delta; 1442 return (*number < number0) != (delta < 0); 1443} 1444 1445static int 1446normalize_overflow(tensptr, unitsptr, base) 1447int * const tensptr; 1448int * const unitsptr; 1449const int base; 1450{ 1451 int tensdelta; 1452 1453 tensdelta = (*unitsptr >= 0) ? 1454 (*unitsptr / base) : 1455 (-1 - (-1 - *unitsptr) / base); 1456 *unitsptr -= tensdelta * base; 1457 return increment_overflow(tensptr, tensdelta); 1458} 1459 1460static int 1461tmcomp(atmp, btmp) 1462const struct tm * const atmp; 1463const struct tm * const btmp; 1464{ 1465 int result; 1466 1467 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 && 1468 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 && 1469 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && 1470 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && 1471 (result = (atmp->tm_min - btmp->tm_min)) == 0) 1472 result = atmp->tm_sec - btmp->tm_sec; 1473 return result; 1474} 1475 1476static time_t 1477time2sub(tmp, funcp, offset, okayp, do_norm_secs) 1478struct tm * const tmp; 1479void (* const funcp)(const time_t*, long, struct tm*); 1480const long offset; 1481int * const okayp; 1482const int do_norm_secs; 1483{ 1484 const struct state * sp; 1485 int dir; 1486 int bits; 1487 int i, j ; 1488 int saved_seconds; 1489 time_t newt; 1490 time_t t; 1491 struct tm yourtm, mytm; 1492 1493 *okayp = FALSE; 1494 yourtm = *tmp; 1495 if (do_norm_secs) { 1496 if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec, 1497 SECSPERMIN)) 1498 return WRONG; 1499 } 1500 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) 1501 return WRONG; 1502 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) 1503 return WRONG; 1504 if (normalize_overflow(&yourtm.tm_year, &yourtm.tm_mon, MONSPERYEAR)) 1505 return WRONG; 1506 /* 1507 ** Turn yourtm.tm_year into an actual year number for now. 1508 ** It is converted back to an offset from TM_YEAR_BASE later. 1509 */ 1510 if (increment_overflow(&yourtm.tm_year, TM_YEAR_BASE)) 1511 return WRONG; 1512 while (yourtm.tm_mday <= 0) { 1513 if (increment_overflow(&yourtm.tm_year, -1)) 1514 return WRONG; 1515 i = yourtm.tm_year + (1 < yourtm.tm_mon); 1516 yourtm.tm_mday += year_lengths[isleap(i)]; 1517 } 1518 while (yourtm.tm_mday > DAYSPERLYEAR) { 1519 i = yourtm.tm_year + (1 < yourtm.tm_mon); 1520 yourtm.tm_mday -= year_lengths[isleap(i)]; 1521 if (increment_overflow(&yourtm.tm_year, 1)) 1522 return WRONG; 1523 } 1524 for ( ; ; ) { 1525 i = mon_lengths[isleap(yourtm.tm_year)][yourtm.tm_mon]; 1526 if (yourtm.tm_mday <= i) 1527 break; 1528 yourtm.tm_mday -= i; 1529 if (++yourtm.tm_mon >= MONSPERYEAR) { 1530 yourtm.tm_mon = 0; 1531 if (increment_overflow(&yourtm.tm_year, 1)) 1532 return WRONG; 1533 } 1534 } 1535 if (increment_overflow(&yourtm.tm_year, -TM_YEAR_BASE)) 1536 return WRONG; 1537 /* Don't go below 1900 for POLA */ 1538 if (yourtm.tm_year < 0) 1539 return WRONG; 1540 if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN) 1541 saved_seconds = 0; 1542 else if (yourtm.tm_year + TM_YEAR_BASE < EPOCH_YEAR) { 1543 /* 1544 ** We can't set tm_sec to 0, because that might push the 1545 ** time below the minimum representable time. 1546 ** Set tm_sec to 59 instead. 1547 ** This assumes that the minimum representable time is 1548 ** not in the same minute that a leap second was deleted from, 1549 ** which is a safer assumption than using 58 would be. 1550 */ 1551 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) 1552 return WRONG; 1553 saved_seconds = yourtm.tm_sec; 1554 yourtm.tm_sec = SECSPERMIN - 1; 1555 } else { 1556 saved_seconds = yourtm.tm_sec; 1557 yourtm.tm_sec = 0; 1558 } 1559 /* 1560 ** Divide the search space in half 1561 ** (this works whether time_t is signed or unsigned). 1562 */ 1563 bits = TYPE_BIT(time_t) - 1; 1564 /* 1565 ** If we have more than this, we will overflow tm_year for tmcomp(). 1566 ** We should really return an error if we cannot represent it. 1567 */ 1568 if (bits > 48) 1569 bits = 48; 1570 /* 1571 ** If time_t is signed, then 0 is just above the median, 1572 ** assuming two's complement arithmetic. 1573 ** If time_t is unsigned, then (1 << bits) is just above the median. 1574 */ 1575 t = TYPE_SIGNED(time_t) ? 0 : (((time_t) 1) << bits); 1576 for ( ; ; ) { 1577 (*funcp)(&t, offset, &mytm); 1578 dir = tmcomp(&mytm, &yourtm); 1579 if (dir != 0) { 1580 if (bits-- < 0) 1581 return WRONG; 1582 if (bits < 0) 1583 --t; /* may be needed if new t is minimal */ 1584 else if (dir > 0) 1585 t -= ((time_t) 1) << bits; 1586 else t += ((time_t) 1) << bits; 1587 continue; 1588 } 1589 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) 1590 break; 1591 /* 1592 ** Right time, wrong type. 1593 ** Hunt for right time, right type. 1594 ** It's okay to guess wrong since the guess 1595 ** gets checked. 1596 */ 1597 sp = (funcp == localsub) ? lclptr : gmtptr; 1598#ifdef ALL_STATE 1599 if (sp == NULL) 1600 return WRONG; 1601#endif /* defined ALL_STATE */ 1602 for (i = sp->typecnt - 1; i >= 0; --i) { 1603 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) 1604 continue; 1605 for (j = sp->typecnt - 1; j >= 0; --j) { 1606 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) 1607 continue; 1608 newt = t + sp->ttis[j].tt_gmtoff - 1609 sp->ttis[i].tt_gmtoff; 1610 (*funcp)(&newt, offset, &mytm); 1611 if (tmcomp(&mytm, &yourtm) != 0) 1612 continue; 1613 if (mytm.tm_isdst != yourtm.tm_isdst) 1614 continue; 1615 /* 1616 ** We have a match. 1617 */ 1618 t = newt; 1619 goto label; 1620 } 1621 } 1622 return WRONG; 1623 } 1624label: 1625 newt = t + saved_seconds; 1626 if ((newt < t) != (saved_seconds < 0)) 1627 return WRONG; 1628 t = newt; 1629 (*funcp)(&t, offset, tmp); 1630 *okayp = TRUE; 1631 return t; 1632} 1633 1634static time_t 1635time2(tmp, funcp, offset, okayp) 1636struct tm * const tmp; 1637void (* const funcp)(const time_t*, long, struct tm*); 1638const long offset; 1639int * const okayp; 1640{ 1641 time_t t; 1642 1643 /* 1644 ** First try without normalization of seconds 1645 ** (in case tm_sec contains a value associated with a leap second). 1646 ** If that fails, try with normalization of seconds. 1647 */ 1648 t = time2sub(tmp, funcp, offset, okayp, FALSE); 1649 return *okayp ? t : time2sub(tmp, funcp, offset, okayp, TRUE); 1650} 1651 1652static time_t 1653time1(tmp, funcp, offset) 1654struct tm * const tmp; 1655void (* const funcp)(const time_t *, long, struct tm *); 1656const long offset; 1657{ 1658 time_t t; 1659 const struct state * sp; 1660 int samei, otheri; 1661 int sameind, otherind; 1662 int i; 1663 int nseen; 1664 int seen[TZ_MAX_TYPES]; 1665 int types[TZ_MAX_TYPES]; 1666 int okay; 1667 1668 if (tmp->tm_isdst > 1) 1669 tmp->tm_isdst = 1; 1670 t = time2(tmp, funcp, offset, &okay); 1671#ifdef PCTS 1672 /* 1673 ** PCTS code courtesy Grant Sullivan (grant@osf.org). 1674 */ 1675 if (okay) 1676 return t; 1677 if (tmp->tm_isdst < 0) 1678 tmp->tm_isdst = 0; /* reset to std and try again */ 1679#endif /* defined PCTS */ 1680#ifndef PCTS 1681 if (okay || tmp->tm_isdst < 0) 1682 return t; 1683#endif /* !defined PCTS */ 1684 /* 1685 ** We're supposed to assume that somebody took a time of one type 1686 ** and did some math on it that yielded a "struct tm" that's bad. 1687 ** We try to divine the type they started from and adjust to the 1688 ** type they need. 1689 */ 1690 sp = (funcp == localsub) ? lclptr : gmtptr; 1691#ifdef ALL_STATE 1692 if (sp == NULL) 1693 return WRONG; 1694#endif /* defined ALL_STATE */ 1695 for (i = 0; i < sp->typecnt; ++i) 1696 seen[i] = FALSE; 1697 nseen = 0; 1698 for (i = sp->timecnt - 1; i >= 0; --i) 1699 if (!seen[sp->types[i]]) { 1700 seen[sp->types[i]] = TRUE; 1701 types[nseen++] = sp->types[i]; 1702 } 1703 for (sameind = 0; sameind < nseen; ++sameind) { 1704 samei = types[sameind]; 1705 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) 1706 continue; 1707 for (otherind = 0; otherind < nseen; ++otherind) { 1708 otheri = types[otherind]; 1709 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) 1710 continue; 1711 tmp->tm_sec += sp->ttis[otheri].tt_gmtoff - 1712 sp->ttis[samei].tt_gmtoff; 1713 tmp->tm_isdst = !tmp->tm_isdst; 1714 t = time2(tmp, funcp, offset, &okay); 1715 if (okay) 1716 return t; 1717 tmp->tm_sec -= sp->ttis[otheri].tt_gmtoff - 1718 sp->ttis[samei].tt_gmtoff; 1719 tmp->tm_isdst = !tmp->tm_isdst; 1720 } 1721 } 1722 return WRONG; 1723} 1724 1725time_t 1726mktime(tmp) 1727struct tm * const tmp; 1728{ 1729 time_t mktime_return_value; 1730 _RWLOCK_RDLOCK(&lcl_rwlock); 1731 tzset_basic(1); 1732 mktime_return_value = time1(tmp, localsub, 0L); 1733 _RWLOCK_UNLOCK(&lcl_rwlock); 1734 return(mktime_return_value); 1735} 1736 1737#ifdef STD_INSPIRED 1738 1739time_t 1740timelocal(tmp) 1741struct tm * const tmp; 1742{ 1743 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 1744 return mktime(tmp); 1745} 1746 1747time_t 1748timegm(tmp) 1749struct tm * const tmp; 1750{ 1751 tmp->tm_isdst = 0; 1752 return time1(tmp, gmtsub, 0L); 1753} 1754 1755time_t 1756timeoff(tmp, offset) 1757struct tm * const tmp; 1758const long offset; 1759{ 1760 tmp->tm_isdst = 0; 1761 return time1(tmp, gmtsub, offset); 1762} 1763 1764#endif /* defined STD_INSPIRED */ 1765 1766#ifdef CMUCS 1767 1768/* 1769** The following is supplied for compatibility with 1770** previous versions of the CMUCS runtime library. 1771*/ 1772 1773long 1774gtime(tmp) 1775struct tm * const tmp; 1776{ 1777 const time_t t = mktime(tmp); 1778 1779 if (t == WRONG) 1780 return -1; 1781 return t; 1782} 1783 1784#endif /* defined CMUCS */ 1785 1786/* 1787** XXX--is the below the right way to conditionalize?? 1788*/ 1789 1790#ifdef STD_INSPIRED 1791 1792/* 1793** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 1794** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which 1795** is not the case if we are accounting for leap seconds. 1796** So, we provide the following conversion routines for use 1797** when exchanging timestamps with POSIX conforming systems. 1798*/ 1799 1800static long 1801leapcorr(timep) 1802time_t * timep; 1803{ 1804 struct state * sp; 1805 struct lsinfo * lp; 1806 int i; 1807 1808 sp = lclptr; 1809 i = sp->leapcnt; 1810 while (--i >= 0) { 1811 lp = &sp->lsis[i]; 1812 if (*timep >= lp->ls_trans) 1813 return lp->ls_corr; 1814 } 1815 return 0; 1816} 1817 1818time_t 1819time2posix(t) 1820time_t t; 1821{ 1822 tzset(); 1823 return t - leapcorr(&t); 1824} 1825 1826time_t 1827posix2time(t) 1828time_t t; 1829{ 1830 time_t x; 1831 time_t y; 1832 1833 tzset(); 1834 /* 1835 ** For a positive leap second hit, the result 1836 ** is not unique. For a negative leap second 1837 ** hit, the corresponding time doesn't exist, 1838 ** so we return an adjacent second. 1839 */ 1840 x = t + leapcorr(&t); 1841 y = x - leapcorr(&x); 1842 if (y < t) { 1843 do { 1844 x++; 1845 y = x - leapcorr(&x); 1846 } while (y < t); 1847 if (t != y) 1848 return x - 1; 1849 } else if (y > t) { 1850 do { 1851 --x; 1852 y = x - leapcorr(&x); 1853 } while (y > t); 1854 if (t != y) 1855 return x + 1; 1856 } 1857 return x; 1858} 1859 1860#endif /* defined STD_INSPIRED */ 1861