1 /* 2 ** This file is in the public domain, so clarified as of 3 ** June 5, 1996 by Arthur David Olson (arthur_david_olson@nih.gov). 4 ** 5 ** $FreeBSD: src/lib/libc/stdtime/localtime.c,v 1.25.2.2 2002/08/13 16:08:07 bmilekic Exp $ 6 ** $DragonFly: src/lib/libc/stdtime/localtime.c,v 1.4 2005/01/31 22:29:44 dillon Exp $ 7 */ 8 9 /* 10 * @(#)localtime.c 7.57 11 */ 12 /* 13 ** Leap second handling from Bradley White (bww@k.gp.cs.cmu.edu). 14 ** POSIX-style TZ environment variable handling from Guy Harris 15 ** (guy@auspex.com). 16 */ 17 18 /*LINTLIBRARY*/ 19 20 #include "namespace.h" 21 #include <sys/types.h> 22 #include <sys/stat.h> 23 24 #include <fcntl.h> 25 #include <pthread.h> 26 #include "private.h" 27 #include <un-namespace.h> 28 29 #include "tzfile.h" 30 31 #include "libc_private.h" 32 33 #define _MUTEX_LOCK(x) if (__isthreaded) _pthread_mutex_lock(x) 34 #define _MUTEX_UNLOCK(x) if (__isthreaded) _pthread_mutex_unlock(x) 35 36 /* 37 ** SunOS 4.1.1 headers lack O_BINARY. 38 */ 39 40 #ifdef O_BINARY 41 #define OPEN_MODE (O_RDONLY | O_BINARY) 42 #endif /* defined O_BINARY */ 43 #ifndef O_BINARY 44 #define OPEN_MODE O_RDONLY 45 #endif /* !defined O_BINARY */ 46 47 #ifndef WILDABBR 48 /* 49 ** Someone might make incorrect use of a time zone abbreviation: 50 ** 1. They might reference tzname[0] before calling tzset (explicitly 51 ** or implicitly). 52 ** 2. They might reference tzname[1] before calling tzset (explicitly 53 ** or implicitly). 54 ** 3. They might reference tzname[1] after setting to a time zone 55 ** in which Daylight Saving Time is never observed. 56 ** 4. They might reference tzname[0] after setting to a time zone 57 ** in which Standard Time is never observed. 58 ** 5. They might reference tm.TM_ZONE after calling offtime. 59 ** What's best to do in the above cases is open to debate; 60 ** for now, we just set things up so that in any of the five cases 61 ** WILDABBR is used. Another possibility: initialize tzname[0] to the 62 ** string "tzname[0] used before set", and similarly for the other cases. 63 ** And another: initialize tzname[0] to "ERA", with an explanation in the 64 ** manual page of what this "time zone abbreviation" means (doing this so 65 ** that tzname[0] has the "normal" length of three characters). 66 */ 67 #define WILDABBR " " 68 #endif /* !defined WILDABBR */ 69 70 static char wildabbr[] = "WILDABBR"; 71 72 static const char gmt[] = "GMT"; 73 74 struct ttinfo { /* time type information */ 75 long tt_gmtoff; /* GMT offset in seconds */ 76 int tt_isdst; /* used to set tm_isdst */ 77 int tt_abbrind; /* abbreviation list index */ 78 int tt_ttisstd; /* TRUE if transition is std time */ 79 int tt_ttisgmt; /* TRUE if transition is GMT */ 80 }; 81 82 struct lsinfo { /* leap second information */ 83 time_t ls_trans; /* transition time */ 84 long ls_corr; /* correction to apply */ 85 }; 86 87 #define BIGGEST(a, b) (((a) > (b)) ? (a) : (b)) 88 89 #ifdef TZNAME_MAX 90 #define MY_TZNAME_MAX TZNAME_MAX 91 #endif /* defined TZNAME_MAX */ 92 #ifndef TZNAME_MAX 93 #define MY_TZNAME_MAX 255 94 #endif /* !defined TZNAME_MAX */ 95 96 struct state { 97 int leapcnt; 98 int timecnt; 99 int typecnt; 100 int charcnt; 101 time_t ats[TZ_MAX_TIMES]; 102 unsigned char types[TZ_MAX_TIMES]; 103 struct ttinfo ttis[TZ_MAX_TYPES]; 104 char chars[BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt), 105 (2 * (MY_TZNAME_MAX + 1)))]; 106 struct lsinfo lsis[TZ_MAX_LEAPS]; 107 }; 108 109 struct rule { 110 int r_type; /* type of rule--see below */ 111 int r_day; /* day number of rule */ 112 int r_week; /* week number of rule */ 113 int r_mon; /* month number of rule */ 114 long r_time; /* transition time of rule */ 115 }; 116 117 #define JULIAN_DAY 0 /* Jn - Julian day */ 118 #define DAY_OF_YEAR 1 /* n - day of year */ 119 #define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */ 120 121 /* 122 ** Prototypes for static functions. 123 */ 124 125 static long detzcode P((const char * codep)); 126 static const char * getzname P((const char * strp)); 127 static const char * getnum P((const char * strp, int * nump, int min, 128 int max)); 129 static const char * getsecs P((const char * strp, long * secsp)); 130 static const char * getoffset P((const char * strp, long * offsetp)); 131 static const char * getrule P((const char * strp, struct rule * rulep)); 132 static void gmtload P((struct state * sp)); 133 static void gmtsub P((const time_t * timep, long offset, 134 struct tm * tmp)); 135 static void localsub P((const time_t * timep, long offset, 136 struct tm * tmp)); 137 static int increment_overflow P((int * number, int delta)); 138 static int normalize_overflow P((int * tensptr, int * unitsptr, 139 int base)); 140 static void settzname P((void)); 141 static time_t time1 P((struct tm * tmp, 142 void(*funcp) P((const time_t *, 143 long, struct tm *)), 144 long offset)); 145 static time_t time2 P((struct tm *tmp, 146 void(*funcp) P((const time_t *, 147 long, struct tm*)), 148 long offset, int * okayp)); 149 static void timesub P((const time_t * timep, long offset, 150 const struct state * sp, struct tm * tmp)); 151 static int tmcomp P((const struct tm * atmp, 152 const struct tm * btmp)); 153 static time_t transtime P((time_t janfirst, int year, 154 const struct rule * rulep, long offset)); 155 static int tzload P((const char * name, struct state * sp)); 156 static int tzparse P((const char * name, struct state * sp, 157 int lastditch)); 158 159 #ifdef ALL_STATE 160 static struct state * lclptr; 161 static struct state * gmtptr; 162 #endif /* defined ALL_STATE */ 163 164 #ifndef ALL_STATE 165 static struct state lclmem; 166 static struct state gmtmem; 167 #define lclptr (&lclmem) 168 #define gmtptr (&gmtmem) 169 #endif /* State Farm */ 170 171 #ifndef TZ_STRLEN_MAX 172 #define TZ_STRLEN_MAX 255 173 #endif /* !defined TZ_STRLEN_MAX */ 174 175 static char lcl_TZname[TZ_STRLEN_MAX + 1]; 176 static int lcl_is_set; 177 static int gmt_is_set; 178 static pthread_mutex_t lcl_mutex = PTHREAD_MUTEX_INITIALIZER; 179 static pthread_mutex_t gmt_mutex = PTHREAD_MUTEX_INITIALIZER; 180 181 char * tzname[2] = { 182 wildabbr, 183 wildabbr 184 }; 185 186 /* 187 ** Section 4.12.3 of X3.159-1989 requires that 188 ** Except for the strftime function, these functions [asctime, 189 ** ctime, gmtime, localtime] return values in one of two static 190 ** objects: a broken-down time structure and an array of char. 191 ** Thanks to Paul Eggert (eggert@twinsun.com) for noting this. 192 */ 193 194 static struct tm tm; 195 196 #ifdef USG_COMPAT 197 time_t timezone = 0; 198 int daylight = 0; 199 #endif /* defined USG_COMPAT */ 200 201 #ifdef ALTZONE 202 time_t altzone = 0; 203 #endif /* defined ALTZONE */ 204 205 static long 206 detzcode(codep) 207 const char * const codep; 208 { 209 long result; 210 int i; 211 212 result = (codep[0] & 0x80) ? ~0L : 0L; 213 for (i = 0; i < 4; ++i) 214 result = (result << 8) | (codep[i] & 0xff); 215 return result; 216 } 217 218 static void 219 settzname P((void)) 220 { 221 struct state * sp = lclptr; 222 int i; 223 224 tzname[0] = wildabbr; 225 tzname[1] = wildabbr; 226 #ifdef USG_COMPAT 227 daylight = 0; 228 timezone = 0; 229 #endif /* defined USG_COMPAT */ 230 #ifdef ALTZONE 231 altzone = 0; 232 #endif /* defined ALTZONE */ 233 #ifdef ALL_STATE 234 if (sp == NULL) { 235 tzname[0] = tzname[1] = gmt; 236 return; 237 } 238 #endif /* defined ALL_STATE */ 239 for (i = 0; i < sp->typecnt; ++i) { 240 const struct ttinfo * const ttisp = &sp->ttis[i]; 241 242 tzname[ttisp->tt_isdst] = 243 &sp->chars[ttisp->tt_abbrind]; 244 #ifdef USG_COMPAT 245 if (ttisp->tt_isdst) 246 daylight = 1; 247 if (i == 0 || !ttisp->tt_isdst) 248 timezone = -(ttisp->tt_gmtoff); 249 #endif /* defined USG_COMPAT */ 250 #ifdef ALTZONE 251 if (i == 0 || ttisp->tt_isdst) 252 altzone = -(ttisp->tt_gmtoff); 253 #endif /* defined ALTZONE */ 254 } 255 /* 256 ** And to get the latest zone names into tzname. . . 257 */ 258 for (i = 0; i < sp->timecnt; ++i) { 259 const struct ttinfo * const ttisp = 260 &sp->ttis[ 261 sp->types[i]]; 262 263 tzname[ttisp->tt_isdst] = 264 &sp->chars[ttisp->tt_abbrind]; 265 } 266 } 267 268 static int 269 tzload(name, sp) 270 const char * name; 271 struct state * const sp; 272 { 273 const char * p; 274 int i; 275 int fid; 276 277 /* XXX The following is from OpenBSD, and I'm not sure it is correct */ 278 if (name != NULL && issetugid() != 0) 279 if ((name[0] == ':' && name[1] == '/') || 280 name[0] == '/' || strchr(name, '.')) 281 name = NULL; 282 if (name == NULL && (name = TZDEFAULT) == NULL) 283 return -1; 284 { 285 int doaccess; 286 struct stat stab; 287 /* 288 ** Section 4.9.1 of the C standard says that 289 ** "FILENAME_MAX expands to an integral constant expression 290 ** that is the size needed for an array of char large enough 291 ** to hold the longest file name string that the implementation 292 ** guarantees can be opened." 293 */ 294 char fullname[FILENAME_MAX + 1]; 295 296 if (name[0] == ':') 297 ++name; 298 doaccess = name[0] == '/'; 299 if (!doaccess) { 300 if ((p = TZDIR) == NULL) 301 return -1; 302 if ((strlen(p) + 1 + strlen(name) + 1) >= sizeof fullname) 303 return -1; 304 (void) strcpy(fullname, p); 305 (void) strcat(fullname, "/"); 306 (void) strcat(fullname, name); 307 /* 308 ** Set doaccess if '.' (as in "../") shows up in name. 309 */ 310 if (strchr(name, '.') != NULL) 311 doaccess = TRUE; 312 name = fullname; 313 } 314 if (doaccess && access(name, R_OK) != 0) 315 return -1; 316 if ((fid = _open(name, OPEN_MODE)) == -1) 317 return -1; 318 if ((_fstat(fid, &stab) < 0) || !S_ISREG(stab.st_mode)) { 319 _close(fid); 320 return -1; 321 } 322 } 323 { 324 struct tzhead * tzhp; 325 char buf[sizeof *sp + sizeof *tzhp]; 326 int ttisstdcnt; 327 int ttisgmtcnt; 328 329 i = _read(fid, buf, sizeof buf); 330 if (_close(fid) != 0) 331 return -1; 332 p = buf; 333 p += (sizeof tzhp->tzh_magic) + (sizeof tzhp->tzh_reserved); 334 ttisstdcnt = (int) detzcode(p); 335 p += 4; 336 ttisgmtcnt = (int) detzcode(p); 337 p += 4; 338 sp->leapcnt = (int) detzcode(p); 339 p += 4; 340 sp->timecnt = (int) detzcode(p); 341 p += 4; 342 sp->typecnt = (int) detzcode(p); 343 p += 4; 344 sp->charcnt = (int) detzcode(p); 345 p += 4; 346 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS || 347 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES || 348 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES || 349 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS || 350 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) || 351 (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0)) 352 return -1; 353 if (i - (p - buf) < sp->timecnt * 4 + /* ats */ 354 sp->timecnt + /* types */ 355 sp->typecnt * (4 + 2) + /* ttinfos */ 356 sp->charcnt + /* chars */ 357 sp->leapcnt * (4 + 4) + /* lsinfos */ 358 ttisstdcnt + /* ttisstds */ 359 ttisgmtcnt) /* ttisgmts */ 360 return -1; 361 for (i = 0; i < sp->timecnt; ++i) { 362 sp->ats[i] = detzcode(p); 363 p += 4; 364 } 365 for (i = 0; i < sp->timecnt; ++i) { 366 sp->types[i] = (unsigned char) *p++; 367 if (sp->types[i] >= sp->typecnt) 368 return -1; 369 } 370 for (i = 0; i < sp->typecnt; ++i) { 371 struct ttinfo * ttisp; 372 373 ttisp = &sp->ttis[i]; 374 ttisp->tt_gmtoff = detzcode(p); 375 p += 4; 376 ttisp->tt_isdst = (unsigned char) *p++; 377 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1) 378 return -1; 379 ttisp->tt_abbrind = (unsigned char) *p++; 380 if (ttisp->tt_abbrind < 0 || 381 ttisp->tt_abbrind > sp->charcnt) 382 return -1; 383 } 384 for (i = 0; i < sp->charcnt; ++i) 385 sp->chars[i] = *p++; 386 sp->chars[i] = '\0'; /* ensure '\0' at end */ 387 for (i = 0; i < sp->leapcnt; ++i) { 388 struct lsinfo * lsisp; 389 390 lsisp = &sp->lsis[i]; 391 lsisp->ls_trans = detzcode(p); 392 p += 4; 393 lsisp->ls_corr = detzcode(p); 394 p += 4; 395 } 396 for (i = 0; i < sp->typecnt; ++i) { 397 struct ttinfo * ttisp; 398 399 ttisp = &sp->ttis[i]; 400 if (ttisstdcnt == 0) 401 ttisp->tt_ttisstd = FALSE; 402 else { 403 ttisp->tt_ttisstd = *p++; 404 if (ttisp->tt_ttisstd != TRUE && 405 ttisp->tt_ttisstd != FALSE) 406 return -1; 407 } 408 } 409 for (i = 0; i < sp->typecnt; ++i) { 410 struct ttinfo * ttisp; 411 412 ttisp = &sp->ttis[i]; 413 if (ttisgmtcnt == 0) 414 ttisp->tt_ttisgmt = FALSE; 415 else { 416 ttisp->tt_ttisgmt = *p++; 417 if (ttisp->tt_ttisgmt != TRUE && 418 ttisp->tt_ttisgmt != FALSE) 419 return -1; 420 } 421 } 422 } 423 return 0; 424 } 425 426 static const int mon_lengths[2][MONSPERYEAR] = { 427 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, 428 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } 429 }; 430 431 static const int year_lengths[2] = { 432 DAYSPERNYEAR, DAYSPERLYEAR 433 }; 434 435 /* 436 ** Given a pointer into a time zone string, scan until a character that is not 437 ** a valid character in a zone name is found. Return a pointer to that 438 ** character. 439 */ 440 441 static const char * 442 getzname(strp) 443 const char * strp; 444 { 445 char c; 446 447 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && 448 c != '+') 449 ++strp; 450 return strp; 451 } 452 453 /* 454 ** Given a pointer into a time zone string, extract a number from that string. 455 ** Check that the number is within a specified range; if it is not, return 456 ** NULL. 457 ** Otherwise, return a pointer to the first character not part of the number. 458 */ 459 460 static const char * 461 getnum(strp, nump, min, max) 462 const char * strp; 463 int * const nump; 464 const int min; 465 const int max; 466 { 467 char c; 468 int num; 469 470 if (strp == NULL || !is_digit(c = *strp)) 471 return NULL; 472 num = 0; 473 do { 474 num = num * 10 + (c - '0'); 475 if (num > max) 476 return NULL; /* illegal value */ 477 c = *++strp; 478 } while (is_digit(c)); 479 if (num < min) 480 return NULL; /* illegal value */ 481 *nump = num; 482 return strp; 483 } 484 485 /* 486 ** Given a pointer into a time zone string, extract a number of seconds, 487 ** in hh[:mm[:ss]] form, from the string. 488 ** If any error occurs, return NULL. 489 ** Otherwise, return a pointer to the first character not part of the number 490 ** of seconds. 491 */ 492 493 static const char * 494 getsecs(strp, secsp) 495 const char * strp; 496 long * const secsp; 497 { 498 int num; 499 500 /* 501 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like 502 ** "M10.4.6/26", which does not conform to Posix, 503 ** but which specifies the equivalent of 504 ** ``02:00 on the first Sunday on or after 23 Oct''. 505 */ 506 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); 507 if (strp == NULL) 508 return NULL; 509 *secsp = num * (long) SECSPERHOUR; 510 if (*strp == ':') { 511 ++strp; 512 strp = getnum(strp, &num, 0, MINSPERHOUR - 1); 513 if (strp == NULL) 514 return NULL; 515 *secsp += num * SECSPERMIN; 516 if (*strp == ':') { 517 ++strp; 518 /* `SECSPERMIN' allows for leap seconds. */ 519 strp = getnum(strp, &num, 0, SECSPERMIN); 520 if (strp == NULL) 521 return NULL; 522 *secsp += num; 523 } 524 } 525 return strp; 526 } 527 528 /* 529 ** Given a pointer into a time zone string, extract an offset, in 530 ** [+-]hh[:mm[:ss]] form, from the string. 531 ** If any error occurs, return NULL. 532 ** Otherwise, return a pointer to the first character not part of the time. 533 */ 534 535 static const char * 536 getoffset(strp, offsetp) 537 const char * strp; 538 long * const offsetp; 539 { 540 int neg = 0; 541 542 if (*strp == '-') { 543 neg = 1; 544 ++strp; 545 } else if (*strp == '+') 546 ++strp; 547 strp = getsecs(strp, offsetp); 548 if (strp == NULL) 549 return NULL; /* illegal time */ 550 if (neg) 551 *offsetp = -*offsetp; 552 return strp; 553 } 554 555 /* 556 ** Given a pointer into a time zone string, extract a rule in the form 557 ** date[/time]. See POSIX section 8 for the format of "date" and "time". 558 ** If a valid rule is not found, return NULL. 559 ** Otherwise, return a pointer to the first character not part of the rule. 560 */ 561 562 static const char * 563 getrule(strp, rulep) 564 const char * strp; 565 struct rule * const rulep; 566 { 567 if (*strp == 'J') { 568 /* 569 ** Julian day. 570 */ 571 rulep->r_type = JULIAN_DAY; 572 ++strp; 573 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); 574 } else if (*strp == 'M') { 575 /* 576 ** Month, week, day. 577 */ 578 rulep->r_type = MONTH_NTH_DAY_OF_WEEK; 579 ++strp; 580 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); 581 if (strp == NULL) 582 return NULL; 583 if (*strp++ != '.') 584 return NULL; 585 strp = getnum(strp, &rulep->r_week, 1, 5); 586 if (strp == NULL) 587 return NULL; 588 if (*strp++ != '.') 589 return NULL; 590 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); 591 } else if (is_digit(*strp)) { 592 /* 593 ** Day of year. 594 */ 595 rulep->r_type = DAY_OF_YEAR; 596 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); 597 } else return NULL; /* invalid format */ 598 if (strp == NULL) 599 return NULL; 600 if (*strp == '/') { 601 /* 602 ** Time specified. 603 */ 604 ++strp; 605 strp = getsecs(strp, &rulep->r_time); 606 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ 607 return strp; 608 } 609 610 /* 611 ** Given the Epoch-relative time of January 1, 00:00:00 GMT, in a year, the 612 ** year, a rule, and the offset from GMT at the time that rule takes effect, 613 ** calculate the Epoch-relative time that rule takes effect. 614 */ 615 616 static time_t 617 transtime(janfirst, year, rulep, offset) 618 const time_t janfirst; 619 const int year; 620 const struct rule * const rulep; 621 const long offset; 622 { 623 int leapyear; 624 time_t value; 625 int i; 626 int d, m1, yy0, yy1, yy2, dow; 627 628 INITIALIZE(value); 629 leapyear = isleap(year); 630 switch (rulep->r_type) { 631 632 case JULIAN_DAY: 633 /* 634 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap 635 ** years. 636 ** In non-leap years, or if the day number is 59 or less, just 637 ** add SECSPERDAY times the day number-1 to the time of 638 ** January 1, midnight, to get the day. 639 */ 640 value = janfirst + (rulep->r_day - 1) * SECSPERDAY; 641 if (leapyear && rulep->r_day >= 60) 642 value += SECSPERDAY; 643 break; 644 645 case DAY_OF_YEAR: 646 /* 647 ** n - day of year. 648 ** Just add SECSPERDAY times the day number to the time of 649 ** January 1, midnight, to get the day. 650 */ 651 value = janfirst + rulep->r_day * SECSPERDAY; 652 break; 653 654 case MONTH_NTH_DAY_OF_WEEK: 655 /* 656 ** Mm.n.d - nth "dth day" of month m. 657 */ 658 value = janfirst; 659 for (i = 0; i < rulep->r_mon - 1; ++i) 660 value += mon_lengths[leapyear][i] * SECSPERDAY; 661 662 /* 663 ** Use Zeller's Congruence to get day-of-week of first day of 664 ** month. 665 */ 666 m1 = (rulep->r_mon + 9) % 12 + 1; 667 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; 668 yy1 = yy0 / 100; 669 yy2 = yy0 % 100; 670 dow = ((26 * m1 - 2) / 10 + 671 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; 672 if (dow < 0) 673 dow += DAYSPERWEEK; 674 675 /* 676 ** "dow" is the day-of-week of the first day of the month. Get 677 ** the day-of-month (zero-origin) of the first "dow" day of the 678 ** month. 679 */ 680 d = rulep->r_day - dow; 681 if (d < 0) 682 d += DAYSPERWEEK; 683 for (i = 1; i < rulep->r_week; ++i) { 684 if (d + DAYSPERWEEK >= 685 mon_lengths[leapyear][rulep->r_mon - 1]) 686 break; 687 d += DAYSPERWEEK; 688 } 689 690 /* 691 ** "d" is the day-of-month (zero-origin) of the day we want. 692 */ 693 value += d * SECSPERDAY; 694 break; 695 } 696 697 /* 698 ** "value" is the Epoch-relative time of 00:00:00 GMT on the day in 699 ** question. To get the Epoch-relative time of the specified local 700 ** time on that day, add the transition time and the current offset 701 ** from GMT. 702 */ 703 return value + rulep->r_time + offset; 704 } 705 706 /* 707 ** Given a POSIX section 8-style TZ string, fill in the rule tables as 708 ** appropriate. 709 */ 710 711 static int 712 tzparse(name, sp, lastditch) 713 const char * name; 714 struct state * const sp; 715 const int lastditch; 716 { 717 const char * stdname; 718 const char * dstname; 719 size_t stdlen; 720 size_t dstlen; 721 long stdoffset; 722 long dstoffset; 723 time_t * atp; 724 unsigned char * typep; 725 char * cp; 726 int load_result; 727 728 INITIALIZE(dstname); 729 stdname = name; 730 if (lastditch) { 731 stdlen = strlen(name); /* length of standard zone name */ 732 name += stdlen; 733 if (stdlen >= sizeof sp->chars) 734 stdlen = (sizeof sp->chars) - 1; 735 stdoffset = 0; 736 } else { 737 name = getzname(name); 738 stdlen = name - stdname; 739 if (stdlen < 3) 740 return -1; 741 if (*name == '\0') 742 return -1; /* was "stdoffset = 0;" */ 743 else { 744 name = getoffset(name, &stdoffset); 745 if (name == NULL) 746 return -1; 747 } 748 } 749 load_result = tzload(TZDEFRULES, sp); 750 if (load_result != 0) 751 sp->leapcnt = 0; /* so, we're off a little */ 752 if (*name != '\0') { 753 dstname = name; 754 name = getzname(name); 755 dstlen = name - dstname; /* length of DST zone name */ 756 if (dstlen < 3) 757 return -1; 758 if (*name != '\0' && *name != ',' && *name != ';') { 759 name = getoffset(name, &dstoffset); 760 if (name == NULL) 761 return -1; 762 } else dstoffset = stdoffset - SECSPERHOUR; 763 if (*name == ',' || *name == ';') { 764 struct rule start; 765 struct rule end; 766 int year; 767 time_t janfirst; 768 time_t starttime; 769 time_t endtime; 770 771 ++name; 772 if ((name = getrule(name, &start)) == NULL) 773 return -1; 774 if (*name++ != ',') 775 return -1; 776 if ((name = getrule(name, &end)) == NULL) 777 return -1; 778 if (*name != '\0') 779 return -1; 780 sp->typecnt = 2; /* standard time and DST */ 781 /* 782 ** Two transitions per year, from EPOCH_YEAR to 2037. 783 */ 784 sp->timecnt = 2 * (2037 - EPOCH_YEAR + 1); 785 if (sp->timecnt > TZ_MAX_TIMES) 786 return -1; 787 sp->ttis[0].tt_gmtoff = -dstoffset; 788 sp->ttis[0].tt_isdst = 1; 789 sp->ttis[0].tt_abbrind = stdlen + 1; 790 sp->ttis[1].tt_gmtoff = -stdoffset; 791 sp->ttis[1].tt_isdst = 0; 792 sp->ttis[1].tt_abbrind = 0; 793 atp = sp->ats; 794 typep = sp->types; 795 janfirst = 0; 796 for (year = EPOCH_YEAR; year <= 2037; ++year) { 797 starttime = transtime(janfirst, year, &start, 798 stdoffset); 799 endtime = transtime(janfirst, year, &end, 800 dstoffset); 801 if (starttime > endtime) { 802 *atp++ = endtime; 803 *typep++ = 1; /* DST ends */ 804 *atp++ = starttime; 805 *typep++ = 0; /* DST begins */ 806 } else { 807 *atp++ = starttime; 808 *typep++ = 0; /* DST begins */ 809 *atp++ = endtime; 810 *typep++ = 1; /* DST ends */ 811 } 812 janfirst += year_lengths[isleap(year)] * 813 SECSPERDAY; 814 } 815 } else { 816 long theirstdoffset; 817 long theirdstoffset; 818 long theiroffset; 819 int isdst; 820 int i; 821 int j; 822 823 if (*name != '\0') 824 return -1; 825 if (load_result != 0) 826 return -1; 827 /* 828 ** Initial values of theirstdoffset and theirdstoffset. 829 */ 830 theirstdoffset = 0; 831 for (i = 0; i < sp->timecnt; ++i) { 832 j = sp->types[i]; 833 if (!sp->ttis[j].tt_isdst) { 834 theirstdoffset = 835 -sp->ttis[j].tt_gmtoff; 836 break; 837 } 838 } 839 theirdstoffset = 0; 840 for (i = 0; i < sp->timecnt; ++i) { 841 j = sp->types[i]; 842 if (sp->ttis[j].tt_isdst) { 843 theirdstoffset = 844 -sp->ttis[j].tt_gmtoff; 845 break; 846 } 847 } 848 /* 849 ** Initially we're assumed to be in standard time. 850 */ 851 isdst = FALSE; 852 theiroffset = theirstdoffset; 853 /* 854 ** Now juggle transition times and types 855 ** tracking offsets as you do. 856 */ 857 for (i = 0; i < sp->timecnt; ++i) { 858 j = sp->types[i]; 859 sp->types[i] = sp->ttis[j].tt_isdst; 860 if (sp->ttis[j].tt_ttisgmt) { 861 /* No adjustment to transition time */ 862 } else { 863 /* 864 ** If summer time is in effect, and the 865 ** transition time was not specified as 866 ** standard time, add the summer time 867 ** offset to the transition time; 868 ** otherwise, add the standard time 869 ** offset to the transition time. 870 */ 871 /* 872 ** Transitions from DST to DDST 873 ** will effectively disappear since 874 ** POSIX provides for only one DST 875 ** offset. 876 */ 877 if (isdst && !sp->ttis[j].tt_ttisstd) { 878 sp->ats[i] += dstoffset - 879 theirdstoffset; 880 } else { 881 sp->ats[i] += stdoffset - 882 theirstdoffset; 883 } 884 } 885 theiroffset = -sp->ttis[j].tt_gmtoff; 886 if (sp->ttis[j].tt_isdst) 887 theirdstoffset = theiroffset; 888 else theirstdoffset = theiroffset; 889 } 890 /* 891 ** Finally, fill in ttis. 892 ** ttisstd and ttisgmt need not be handled. 893 */ 894 sp->ttis[0].tt_gmtoff = -stdoffset; 895 sp->ttis[0].tt_isdst = FALSE; 896 sp->ttis[0].tt_abbrind = 0; 897 sp->ttis[1].tt_gmtoff = -dstoffset; 898 sp->ttis[1].tt_isdst = TRUE; 899 sp->ttis[1].tt_abbrind = stdlen + 1; 900 } 901 } else { 902 dstlen = 0; 903 sp->typecnt = 1; /* only standard time */ 904 sp->timecnt = 0; 905 sp->ttis[0].tt_gmtoff = -stdoffset; 906 sp->ttis[0].tt_isdst = 0; 907 sp->ttis[0].tt_abbrind = 0; 908 } 909 sp->charcnt = stdlen + 1; 910 if (dstlen != 0) 911 sp->charcnt += dstlen + 1; 912 if (sp->charcnt > sizeof sp->chars) 913 return -1; 914 cp = sp->chars; 915 (void) strncpy(cp, stdname, stdlen); 916 cp += stdlen; 917 *cp++ = '\0'; 918 if (dstlen != 0) { 919 (void) strncpy(cp, dstname, dstlen); 920 *(cp + dstlen) = '\0'; 921 } 922 return 0; 923 } 924 925 static void 926 gmtload(sp) 927 struct state * const sp; 928 { 929 if (tzload(gmt, sp) != 0) 930 (void) tzparse(gmt, sp, TRUE); 931 } 932 933 static void 934 tzsetwall_basic(void) 935 { 936 if (lcl_is_set < 0) 937 return; 938 lcl_is_set = -1; 939 940 #ifdef ALL_STATE 941 if (lclptr == NULL) { 942 lclptr = (struct state *) malloc(sizeof *lclptr); 943 if (lclptr == NULL) { 944 settzname(); /* all we can do */ 945 return; 946 } 947 } 948 #endif /* defined ALL_STATE */ 949 if (tzload((char *) NULL, lclptr) != 0) 950 gmtload(lclptr); 951 settzname(); 952 } 953 954 void 955 tzsetwall P((void)) 956 { 957 _MUTEX_LOCK(&lcl_mutex); 958 tzsetwall_basic(); 959 _MUTEX_UNLOCK(&lcl_mutex); 960 } 961 962 static void 963 tzset_basic (void) 964 { 965 const char * name; 966 967 name = getenv("TZ"); 968 if (name == NULL) { 969 tzsetwall(); 970 return; 971 } 972 973 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) 974 return; 975 lcl_is_set = (strlen(name) < sizeof(lcl_TZname)); 976 if (lcl_is_set) 977 (void) strcpy(lcl_TZname, name); 978 979 #ifdef ALL_STATE 980 if (lclptr == NULL) { 981 lclptr = (struct state *) malloc(sizeof *lclptr); 982 if (lclptr == NULL) { 983 settzname(); /* all we can do */ 984 return; 985 } 986 } 987 #endif /* defined ALL_STATE */ 988 if (*name == '\0') { 989 /* 990 ** User wants it fast rather than right. 991 */ 992 lclptr->leapcnt = 0; /* so, we're off a little */ 993 lclptr->timecnt = 0; 994 lclptr->ttis[0].tt_gmtoff = 0; 995 lclptr->ttis[0].tt_abbrind = 0; 996 (void) strcpy(lclptr->chars, gmt); 997 } else if (tzload(name, lclptr) != 0) 998 if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0) 999 (void) gmtload(lclptr); 1000 settzname(); 1001 } 1002 1003 void 1004 tzset(void) 1005 { 1006 _MUTEX_LOCK(&lcl_mutex); 1007 tzset_basic(); 1008 _MUTEX_UNLOCK(&lcl_mutex); 1009 } 1010 1011 /* 1012 ** The easy way to behave "as if no library function calls" localtime 1013 ** is to not call it--so we drop its guts into "localsub", which can be 1014 ** freely called. (And no, the PANS doesn't require the above behavior-- 1015 ** but it *is* desirable.) 1016 ** 1017 ** The unused offset argument is for the benefit of mktime variants. 1018 */ 1019 1020 /*ARGSUSED*/ 1021 static void 1022 localsub(timep, offset, tmp) 1023 const time_t * const timep; 1024 const long offset; 1025 struct tm * const tmp; 1026 { 1027 struct state * sp; 1028 const struct ttinfo * ttisp; 1029 int i; 1030 const time_t t = *timep; 1031 1032 sp = lclptr; 1033 #ifdef ALL_STATE 1034 if (sp == NULL) { 1035 gmtsub(timep, offset, tmp); 1036 return; 1037 } 1038 #endif /* defined ALL_STATE */ 1039 if (sp->timecnt == 0 || t < sp->ats[0]) { 1040 i = 0; 1041 while (sp->ttis[i].tt_isdst) 1042 if (++i >= sp->typecnt) { 1043 i = 0; 1044 break; 1045 } 1046 } else { 1047 for (i = 1; i < sp->timecnt; ++i) 1048 if (t < sp->ats[i]) 1049 break; 1050 i = sp->types[i - 1]; 1051 } 1052 ttisp = &sp->ttis[i]; 1053 /* 1054 ** To get (wrong) behavior that's compatible with System V Release 2.0 1055 ** you'd replace the statement below with 1056 ** t += ttisp->tt_gmtoff; 1057 ** timesub(&t, 0L, sp, tmp); 1058 */ 1059 timesub(&t, ttisp->tt_gmtoff, sp, tmp); 1060 tmp->tm_isdst = ttisp->tt_isdst; 1061 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind]; 1062 #ifdef TM_ZONE 1063 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind]; 1064 #endif /* defined TM_ZONE */ 1065 } 1066 1067 struct tm * 1068 localtime_r(timep, p_tm) 1069 const time_t * const timep; 1070 struct tm *p_tm; 1071 { 1072 _MUTEX_LOCK(&lcl_mutex); 1073 tzset(); 1074 localsub(timep, 0L, p_tm); 1075 _MUTEX_UNLOCK(&lcl_mutex); 1076 return(p_tm); 1077 } 1078 1079 struct tm * 1080 localtime(timep) 1081 const time_t * const timep; 1082 { 1083 static pthread_mutex_t localtime_mutex = PTHREAD_MUTEX_INITIALIZER; 1084 static pthread_key_t localtime_key = -1; 1085 struct tm *p_tm; 1086 1087 if (__isthreaded != 0) { 1088 _pthread_mutex_lock(&localtime_mutex); 1089 if (localtime_key < 0) { 1090 if (_pthread_key_create(&localtime_key, free) < 0) { 1091 _pthread_mutex_unlock(&localtime_mutex); 1092 return(NULL); 1093 } 1094 } 1095 _pthread_mutex_unlock(&localtime_mutex); 1096 p_tm = _pthread_getspecific(localtime_key); 1097 if (p_tm == NULL) { 1098 if ((p_tm = (struct tm *)malloc(sizeof(struct tm))) 1099 == NULL) 1100 return(NULL); 1101 _pthread_setspecific(localtime_key, p_tm); 1102 } 1103 _pthread_mutex_lock(&lcl_mutex); 1104 tzset(); 1105 localsub(timep, 0L, p_tm); 1106 _pthread_mutex_unlock(&lcl_mutex); 1107 return(p_tm); 1108 } else { 1109 tzset(); 1110 localsub(timep, 0L, &tm); 1111 return(&tm); 1112 } 1113 } 1114 1115 /* 1116 ** gmtsub is to gmtime as localsub is to localtime. 1117 */ 1118 1119 static void 1120 gmtsub(timep, offset, tmp) 1121 const time_t * const timep; 1122 const long offset; 1123 struct tm * const tmp; 1124 { 1125 _MUTEX_LOCK(&gmt_mutex); 1126 if (!gmt_is_set) { 1127 gmt_is_set = TRUE; 1128 #ifdef ALL_STATE 1129 gmtptr = (struct state *) malloc(sizeof *gmtptr); 1130 if (gmtptr != NULL) 1131 #endif /* defined ALL_STATE */ 1132 gmtload(gmtptr); 1133 } 1134 _MUTEX_UNLOCK(&gmt_mutex); 1135 timesub(timep, offset, gmtptr, tmp); 1136 #ifdef TM_ZONE 1137 /* 1138 ** Could get fancy here and deliver something such as 1139 ** "GMT+xxxx" or "GMT-xxxx" if offset is non-zero, 1140 ** but this is no time for a treasure hunt. 1141 */ 1142 if (offset != 0) 1143 tmp->TM_ZONE = wildabbr; 1144 else { 1145 #ifdef ALL_STATE 1146 if (gmtptr == NULL) 1147 tmp->TM_ZONE = gmt; 1148 else tmp->TM_ZONE = gmtptr->chars; 1149 #endif /* defined ALL_STATE */ 1150 #ifndef ALL_STATE 1151 tmp->TM_ZONE = gmtptr->chars; 1152 #endif /* State Farm */ 1153 } 1154 #endif /* defined TM_ZONE */ 1155 } 1156 1157 struct tm * 1158 gmtime(timep) 1159 const time_t * const timep; 1160 { 1161 static pthread_mutex_t gmtime_mutex = PTHREAD_MUTEX_INITIALIZER; 1162 static pthread_key_t gmtime_key = -1; 1163 struct tm *p_tm; 1164 1165 if (__isthreaded != 0) { 1166 _pthread_mutex_lock(&gmtime_mutex); 1167 if (gmtime_key < 0) { 1168 if (_pthread_key_create(&gmtime_key, free) < 0) { 1169 _pthread_mutex_unlock(&gmtime_mutex); 1170 return(NULL); 1171 } 1172 } 1173 _pthread_mutex_unlock(&gmtime_mutex); 1174 /* 1175 * Changed to follow POSIX.1 threads standard, which 1176 * is what BSD currently has. 1177 */ 1178 if ((p_tm = _pthread_getspecific(gmtime_key)) == NULL) { 1179 if ((p_tm = (struct tm *)malloc(sizeof(struct tm))) 1180 == NULL) { 1181 return(NULL); 1182 } 1183 _pthread_setspecific(gmtime_key, p_tm); 1184 } 1185 gmtsub(timep, 0L, p_tm); 1186 return(p_tm); 1187 } 1188 else { 1189 gmtsub(timep, 0L, &tm); 1190 return(&tm); 1191 } 1192 } 1193 1194 struct tm * 1195 gmtime_r(const time_t * timep, struct tm * tm) 1196 { 1197 gmtsub(timep, 0L, tm); 1198 return(tm); 1199 } 1200 1201 #ifdef STD_INSPIRED 1202 1203 struct tm * 1204 offtime(timep, offset) 1205 const time_t * const timep; 1206 const long offset; 1207 { 1208 gmtsub(timep, offset, &tm); 1209 return &tm; 1210 } 1211 1212 #endif /* defined STD_INSPIRED */ 1213 1214 static void 1215 timesub(timep, offset, sp, tmp) 1216 const time_t * const timep; 1217 const long offset; 1218 const struct state * const sp; 1219 struct tm * const tmp; 1220 { 1221 const struct lsinfo * lp; 1222 long days; 1223 long rem; 1224 int y; 1225 int yleap; 1226 const int * ip; 1227 long corr; 1228 int hit; 1229 int i; 1230 1231 corr = 0; 1232 hit = 0; 1233 #ifdef ALL_STATE 1234 i = (sp == NULL) ? 0 : sp->leapcnt; 1235 #endif /* defined ALL_STATE */ 1236 #ifndef ALL_STATE 1237 i = sp->leapcnt; 1238 #endif /* State Farm */ 1239 while (--i >= 0) { 1240 lp = &sp->lsis[i]; 1241 if (*timep >= lp->ls_trans) { 1242 if (*timep == lp->ls_trans) { 1243 hit = ((i == 0 && lp->ls_corr > 0) || 1244 lp->ls_corr > sp->lsis[i - 1].ls_corr); 1245 if (hit) 1246 while (i > 0 && 1247 sp->lsis[i].ls_trans == 1248 sp->lsis[i - 1].ls_trans + 1 && 1249 sp->lsis[i].ls_corr == 1250 sp->lsis[i - 1].ls_corr + 1) { 1251 ++hit; 1252 --i; 1253 } 1254 } 1255 corr = lp->ls_corr; 1256 break; 1257 } 1258 } 1259 days = *timep / SECSPERDAY; 1260 rem = *timep % SECSPERDAY; 1261 #ifdef mc68k 1262 if (*timep == 0x80000000) { 1263 /* 1264 ** A 3B1 muffs the division on the most negative number. 1265 */ 1266 days = -24855; 1267 rem = -11648; 1268 } 1269 #endif /* defined mc68k */ 1270 rem += (offset - corr); 1271 while (rem < 0) { 1272 rem += SECSPERDAY; 1273 --days; 1274 } 1275 while (rem >= SECSPERDAY) { 1276 rem -= SECSPERDAY; 1277 ++days; 1278 } 1279 tmp->tm_hour = (int) (rem / SECSPERHOUR); 1280 rem = rem % SECSPERHOUR; 1281 tmp->tm_min = (int) (rem / SECSPERMIN); 1282 /* 1283 ** A positive leap second requires a special 1284 ** representation. This uses "... ??:59:60" et seq. 1285 */ 1286 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit; 1287 tmp->tm_wday = (int) ((EPOCH_WDAY + days) % DAYSPERWEEK); 1288 if (tmp->tm_wday < 0) 1289 tmp->tm_wday += DAYSPERWEEK; 1290 y = EPOCH_YEAR; 1291 #define LEAPS_THRU_END_OF(y) ((y) / 4 - (y) / 100 + (y) / 400) 1292 while (days < 0 || days >= (long) year_lengths[yleap = isleap(y)]) { 1293 int newy; 1294 1295 newy = y + days / DAYSPERNYEAR; 1296 if (days < 0) 1297 --newy; 1298 days -= (newy - y) * DAYSPERNYEAR + 1299 LEAPS_THRU_END_OF(newy - 1) - 1300 LEAPS_THRU_END_OF(y - 1); 1301 y = newy; 1302 } 1303 tmp->tm_year = y - TM_YEAR_BASE; 1304 tmp->tm_yday = (int) days; 1305 ip = mon_lengths[yleap]; 1306 for (tmp->tm_mon = 0; days >= (long) ip[tmp->tm_mon]; ++(tmp->tm_mon)) 1307 days = days - (long) ip[tmp->tm_mon]; 1308 tmp->tm_mday = (int) (days + 1); 1309 tmp->tm_isdst = 0; 1310 #ifdef TM_GMTOFF 1311 tmp->TM_GMTOFF = offset; 1312 #endif /* defined TM_GMTOFF */ 1313 } 1314 1315 char * 1316 ctime(timep) 1317 const time_t * const timep; 1318 { 1319 /* 1320 ** Section 4.12.3.2 of X3.159-1989 requires that 1321 ** The ctime funciton converts the calendar time pointed to by timer 1322 ** to local time in the form of a string. It is equivalent to 1323 ** asctime(localtime(timer)) 1324 */ 1325 return asctime(localtime(timep)); 1326 } 1327 1328 char * 1329 ctime_r(timep, buf) 1330 const time_t * const timep; 1331 char *buf; 1332 { 1333 struct tm tm; 1334 return asctime_r(localtime_r(timep, &tm), buf); 1335 } 1336 1337 /* 1338 ** Adapted from code provided by Robert Elz, who writes: 1339 ** The "best" way to do mktime I think is based on an idea of Bob 1340 ** Kridle's (so its said...) from a long time ago. 1341 ** [kridle@xinet.com as of 1996-01-16.] 1342 ** It does a binary search of the time_t space. Since time_t's are 1343 ** just 32 bits, its a max of 32 iterations (even at 64 bits it 1344 ** would still be very reasonable). 1345 */ 1346 1347 #ifndef WRONG 1348 #define WRONG (-1) 1349 #endif /* !defined WRONG */ 1350 1351 /* 1352 ** Simplified normalize logic courtesy Paul Eggert (eggert@twinsun.com). 1353 */ 1354 1355 static int 1356 increment_overflow(number, delta) 1357 int * number; 1358 int delta; 1359 { 1360 int number0; 1361 1362 number0 = *number; 1363 *number += delta; 1364 return (*number < number0) != (delta < 0); 1365 } 1366 1367 static int 1368 normalize_overflow(tensptr, unitsptr, base) 1369 int * const tensptr; 1370 int * const unitsptr; 1371 const int base; 1372 { 1373 int tensdelta; 1374 1375 tensdelta = (*unitsptr >= 0) ? 1376 (*unitsptr / base) : 1377 (-1 - (-1 - *unitsptr) / base); 1378 *unitsptr -= tensdelta * base; 1379 return increment_overflow(tensptr, tensdelta); 1380 } 1381 1382 static int 1383 tmcomp(atmp, btmp) 1384 const struct tm * const atmp; 1385 const struct tm * const btmp; 1386 { 1387 int result; 1388 1389 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 && 1390 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 && 1391 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && 1392 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && 1393 (result = (atmp->tm_min - btmp->tm_min)) == 0) 1394 result = atmp->tm_sec - btmp->tm_sec; 1395 return result; 1396 } 1397 1398 static time_t 1399 time2(tmp, funcp, offset, okayp) 1400 struct tm * const tmp; 1401 void (* const funcp) P((const time_t*, long, struct tm*)); 1402 const long offset; 1403 int * const okayp; 1404 { 1405 const struct state * sp; 1406 int dir; 1407 int bits; 1408 int i, j ; 1409 int saved_seconds; 1410 time_t newt; 1411 time_t t; 1412 struct tm yourtm, mytm; 1413 1414 *okayp = FALSE; 1415 yourtm = *tmp; 1416 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) 1417 return WRONG; 1418 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) 1419 return WRONG; 1420 if (normalize_overflow(&yourtm.tm_year, &yourtm.tm_mon, MONSPERYEAR)) 1421 return WRONG; 1422 /* 1423 ** Turn yourtm.tm_year into an actual year number for now. 1424 ** It is converted back to an offset from TM_YEAR_BASE later. 1425 */ 1426 if (increment_overflow(&yourtm.tm_year, TM_YEAR_BASE)) 1427 return WRONG; 1428 while (yourtm.tm_mday <= 0) { 1429 if (increment_overflow(&yourtm.tm_year, -1)) 1430 return WRONG; 1431 i = yourtm.tm_year + (1 < yourtm.tm_mon); 1432 yourtm.tm_mday += year_lengths[isleap(i)]; 1433 } 1434 while (yourtm.tm_mday > DAYSPERLYEAR) { 1435 i = yourtm.tm_year + (1 < yourtm.tm_mon); 1436 yourtm.tm_mday -= year_lengths[isleap(i)]; 1437 if (increment_overflow(&yourtm.tm_year, 1)) 1438 return WRONG; 1439 } 1440 for ( ; ; ) { 1441 i = mon_lengths[isleap(yourtm.tm_year)][yourtm.tm_mon]; 1442 if (yourtm.tm_mday <= i) 1443 break; 1444 yourtm.tm_mday -= i; 1445 if (++yourtm.tm_mon >= MONSPERYEAR) { 1446 yourtm.tm_mon = 0; 1447 if (increment_overflow(&yourtm.tm_year, 1)) 1448 return WRONG; 1449 } 1450 } 1451 if (increment_overflow(&yourtm.tm_year, -TM_YEAR_BASE)) 1452 return WRONG; 1453 if (yourtm.tm_year + TM_YEAR_BASE < EPOCH_YEAR) { 1454 /* 1455 ** We can't set tm_sec to 0, because that might push the 1456 ** time below the minimum representable time. 1457 ** Set tm_sec to 59 instead. 1458 ** This assumes that the minimum representable time is 1459 ** not in the same minute that a leap second was deleted from, 1460 ** which is a safer assumption than using 58 would be. 1461 */ 1462 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) 1463 return WRONG; 1464 saved_seconds = yourtm.tm_sec; 1465 yourtm.tm_sec = SECSPERMIN - 1; 1466 } else { 1467 saved_seconds = yourtm.tm_sec; 1468 yourtm.tm_sec = 0; 1469 } 1470 /* 1471 ** Divide the search space in half 1472 ** (this works whether time_t is signed or unsigned). 1473 */ 1474 bits = TYPE_BIT(time_t) - 1; 1475 /* 1476 ** If time_t is signed, then 0 is just above the median, 1477 ** assuming two's complement arithmetic. 1478 ** If time_t is unsigned, then (1 << bits) is just above the median. 1479 */ 1480 t = TYPE_SIGNED(time_t) ? 0 : (((time_t) 1) << bits); 1481 for ( ; ; ) { 1482 (*funcp)(&t, offset, &mytm); 1483 dir = tmcomp(&mytm, &yourtm); 1484 if (dir != 0) { 1485 if (bits-- < 0) 1486 return WRONG; 1487 if (bits < 0) 1488 --t; /* may be needed if new t is minimal */ 1489 else if (dir > 0) 1490 t -= ((time_t) 1) << bits; 1491 else t += ((time_t) 1) << bits; 1492 continue; 1493 } 1494 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) 1495 break; 1496 /* 1497 ** Right time, wrong type. 1498 ** Hunt for right time, right type. 1499 ** It's okay to guess wrong since the guess 1500 ** gets checked. 1501 */ 1502 /* 1503 ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's. 1504 */ 1505 sp = (const struct state *) 1506 (((void *) funcp == (void *) localsub) ? 1507 lclptr : gmtptr); 1508 #ifdef ALL_STATE 1509 if (sp == NULL) 1510 return WRONG; 1511 #endif /* defined ALL_STATE */ 1512 for (i = sp->typecnt - 1; i >= 0; --i) { 1513 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) 1514 continue; 1515 for (j = sp->typecnt - 1; j >= 0; --j) { 1516 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) 1517 continue; 1518 newt = t + sp->ttis[j].tt_gmtoff - 1519 sp->ttis[i].tt_gmtoff; 1520 (*funcp)(&newt, offset, &mytm); 1521 if (tmcomp(&mytm, &yourtm) != 0) 1522 continue; 1523 if (mytm.tm_isdst != yourtm.tm_isdst) 1524 continue; 1525 /* 1526 ** We have a match. 1527 */ 1528 t = newt; 1529 goto label; 1530 } 1531 } 1532 return WRONG; 1533 } 1534 label: 1535 newt = t + saved_seconds; 1536 if ((newt < t) != (saved_seconds < 0)) 1537 return WRONG; 1538 t = newt; 1539 (*funcp)(&t, offset, tmp); 1540 *okayp = TRUE; 1541 return t; 1542 } 1543 1544 static time_t 1545 time1(tmp, funcp, offset) 1546 struct tm * const tmp; 1547 void (* const funcp) P((const time_t *, long, struct tm *)); 1548 const long offset; 1549 { 1550 time_t t; 1551 const struct state * sp; 1552 int samei, otheri; 1553 int okay; 1554 1555 if (tmp->tm_isdst > 1) 1556 tmp->tm_isdst = 1; 1557 t = time2(tmp, funcp, offset, &okay); 1558 #ifdef PCTS 1559 /* 1560 ** PCTS code courtesy Grant Sullivan (grant@osf.org). 1561 */ 1562 if (okay) 1563 return t; 1564 if (tmp->tm_isdst < 0) 1565 tmp->tm_isdst = 0; /* reset to std and try again */ 1566 #endif /* defined PCTS */ 1567 #ifndef PCTS 1568 if (okay || tmp->tm_isdst < 0) 1569 return t; 1570 #endif /* !defined PCTS */ 1571 /* 1572 ** We're supposed to assume that somebody took a time of one type 1573 ** and did some math on it that yielded a "struct tm" that's bad. 1574 ** We try to divine the type they started from and adjust to the 1575 ** type they need. 1576 */ 1577 /* 1578 ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's. 1579 */ 1580 sp = (const struct state *) (((void *) funcp == (void *) localsub) ? 1581 lclptr : gmtptr); 1582 #ifdef ALL_STATE 1583 if (sp == NULL) 1584 return WRONG; 1585 #endif /* defined ALL_STATE */ 1586 for (samei = sp->typecnt - 1; samei >= 0; --samei) { 1587 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) 1588 continue; 1589 for (otheri = sp->typecnt - 1; otheri >= 0; --otheri) { 1590 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) 1591 continue; 1592 tmp->tm_sec += sp->ttis[otheri].tt_gmtoff - 1593 sp->ttis[samei].tt_gmtoff; 1594 tmp->tm_isdst = !tmp->tm_isdst; 1595 t = time2(tmp, funcp, offset, &okay); 1596 if (okay) 1597 return t; 1598 tmp->tm_sec -= sp->ttis[otheri].tt_gmtoff - 1599 sp->ttis[samei].tt_gmtoff; 1600 tmp->tm_isdst = !tmp->tm_isdst; 1601 } 1602 } 1603 return WRONG; 1604 } 1605 1606 time_t 1607 mktime(tmp) 1608 struct tm * const tmp; 1609 { 1610 time_t mktime_return_value; 1611 _MUTEX_LOCK(&lcl_mutex); 1612 tzset(); 1613 mktime_return_value = time1(tmp, localsub, 0L); 1614 _MUTEX_UNLOCK(&lcl_mutex); 1615 return(mktime_return_value); 1616 } 1617 1618 #ifdef STD_INSPIRED 1619 1620 time_t 1621 timelocal(tmp) 1622 struct tm * const tmp; 1623 { 1624 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 1625 return mktime(tmp); 1626 } 1627 1628 time_t 1629 timegm(tmp) 1630 struct tm * const tmp; 1631 { 1632 tmp->tm_isdst = 0; 1633 return time1(tmp, gmtsub, 0L); 1634 } 1635 1636 time_t 1637 timeoff(tmp, offset) 1638 struct tm * const tmp; 1639 const long offset; 1640 { 1641 tmp->tm_isdst = 0; 1642 return time1(tmp, gmtsub, offset); 1643 } 1644 1645 #endif /* defined STD_INSPIRED */ 1646 1647 #ifdef CMUCS 1648 1649 /* 1650 ** The following is supplied for compatibility with 1651 ** previous versions of the CMUCS runtime library. 1652 */ 1653 1654 long 1655 gtime(tmp) 1656 struct tm * const tmp; 1657 { 1658 const time_t t = mktime(tmp); 1659 1660 if (t == WRONG) 1661 return -1; 1662 return t; 1663 } 1664 1665 #endif /* defined CMUCS */ 1666 1667 /* 1668 ** XXX--is the below the right way to conditionalize?? 1669 */ 1670 1671 #ifdef STD_INSPIRED 1672 1673 /* 1674 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 1675 ** shall correspond to "Wed Dec 31 23:59:59 GMT 1986", which 1676 ** is not the case if we are accounting for leap seconds. 1677 ** So, we provide the following conversion routines for use 1678 ** when exchanging timestamps with POSIX conforming systems. 1679 */ 1680 1681 static long 1682 leapcorr(timep) 1683 time_t * timep; 1684 { 1685 struct state * sp; 1686 struct lsinfo * lp; 1687 int i; 1688 1689 sp = lclptr; 1690 i = sp->leapcnt; 1691 while (--i >= 0) { 1692 lp = &sp->lsis[i]; 1693 if (*timep >= lp->ls_trans) 1694 return lp->ls_corr; 1695 } 1696 return 0; 1697 } 1698 1699 time_t 1700 time2posix(t) 1701 time_t t; 1702 { 1703 tzset(); 1704 return t - leapcorr(&t); 1705 } 1706 1707 time_t 1708 posix2time(t) 1709 time_t t; 1710 { 1711 time_t x; 1712 time_t y; 1713 1714 tzset(); 1715 /* 1716 ** For a positive leap second hit, the result 1717 ** is not unique. For a negative leap second 1718 ** hit, the corresponding time doesn't exist, 1719 ** so we return an adjacent second. 1720 */ 1721 x = t + leapcorr(&t); 1722 y = x - leapcorr(&x); 1723 if (y < t) { 1724 do { 1725 x++; 1726 y = x - leapcorr(&x); 1727 } while (y < t); 1728 if (t != y) 1729 return x - 1; 1730 } else if (y > t) { 1731 do { 1732 --x; 1733 y = x - leapcorr(&x); 1734 } while (y > t); 1735 if (t != y) 1736 return x + 1; 1737 } 1738 return x; 1739 } 1740 1741 #endif /* defined STD_INSPIRED */ 1742