1 /* $NetBSD: localtime.c,v 1.7 1996/09/10 22:04:30 jtc Exp $ */ 2 3 /* 4 ** This file is in the public domain, so clarified as of 5 ** June 5, 1996 by Arthur David Olson (arthur_david_olson@nih.gov). 6 */ 7 8 #ifndef lint 9 #ifndef NOID 10 static char elsieid[] = "@(#)localtime.c 7.58"; 11 #endif /* !defined NOID */ 12 #endif /* !defined lint */ 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 "private.h" 23 #include "tzfile.h" 24 #include "fcntl.h" 25 26 /* 27 ** SunOS 4.1.1 headers lack O_BINARY. 28 */ 29 30 #ifdef O_BINARY 31 #define OPEN_MODE (O_RDONLY | O_BINARY) 32 #endif /* defined O_BINARY */ 33 #ifndef O_BINARY 34 #define OPEN_MODE O_RDONLY 35 #endif /* !defined O_BINARY */ 36 37 #ifndef WILDABBR 38 /* 39 ** Someone might make incorrect use of a time zone abbreviation: 40 ** 1. They might reference tzname[0] before calling tzset (explicitly 41 ** or implicitly). 42 ** 2. They might reference tzname[1] before calling tzset (explicitly 43 ** or implicitly). 44 ** 3. They might reference tzname[1] after setting to a time zone 45 ** in which Daylight Saving Time is never observed. 46 ** 4. They might reference tzname[0] after setting to a time zone 47 ** in which Standard Time is never observed. 48 ** 5. They might reference tm.TM_ZONE after calling offtime. 49 ** What's best to do in the above cases is open to debate; 50 ** for now, we just set things up so that in any of the five cases 51 ** WILDABBR is used. Another possibility: initialize tzname[0] to the 52 ** string "tzname[0] used before set", and similarly for the other cases. 53 ** And another: initialize tzname[0] to "ERA", with an explanation in the 54 ** manual page of what this "time zone abbreviation" means (doing this so 55 ** that tzname[0] has the "normal" length of three characters). 56 */ 57 #define WILDABBR " " 58 #endif /* !defined WILDABBR */ 59 60 static char wildabbr[] = "WILDABBR"; 61 62 static const char gmt[] = "GMT"; 63 64 struct ttinfo { /* time type information */ 65 long tt_gmtoff; /* GMT offset in seconds */ 66 int tt_isdst; /* used to set tm_isdst */ 67 int tt_abbrind; /* abbreviation list index */ 68 int tt_ttisstd; /* TRUE if transition is std time */ 69 int tt_ttisgmt; /* TRUE if transition is GMT */ 70 }; 71 72 struct lsinfo { /* leap second information */ 73 time_t ls_trans; /* transition time */ 74 long ls_corr; /* correction to apply */ 75 }; 76 77 #define BIGGEST(a, b) (((a) > (b)) ? (a) : (b)) 78 79 #ifdef TZNAME_MAX 80 #define MY_TZNAME_MAX TZNAME_MAX 81 #endif /* defined TZNAME_MAX */ 82 #ifndef TZNAME_MAX 83 #define MY_TZNAME_MAX 255 84 #endif /* !defined TZNAME_MAX */ 85 86 struct state { 87 int leapcnt; 88 int timecnt; 89 int typecnt; 90 int charcnt; 91 time_t ats[TZ_MAX_TIMES]; 92 unsigned char types[TZ_MAX_TIMES]; 93 struct ttinfo ttis[TZ_MAX_TYPES]; 94 char chars[BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt), 95 (2 * (MY_TZNAME_MAX + 1)))]; 96 struct lsinfo lsis[TZ_MAX_LEAPS]; 97 }; 98 99 struct rule { 100 int r_type; /* type of rule--see below */ 101 int r_day; /* day number of rule */ 102 int r_week; /* week number of rule */ 103 int r_mon; /* month number of rule */ 104 long r_time; /* transition time of rule */ 105 }; 106 107 #define JULIAN_DAY 0 /* Jn - Julian day */ 108 #define DAY_OF_YEAR 1 /* n - day of year */ 109 #define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */ 110 111 /* 112 ** Prototypes for static functions. 113 */ 114 115 static long detzcode P((const char * codep)); 116 static const char * getzname P((const char * strp)); 117 static const char * getnum P((const char * strp, int * nump, int min, 118 int max)); 119 static const char * getsecs P((const char * strp, long * secsp)); 120 static const char * getoffset P((const char * strp, long * offsetp)); 121 static const char * getrule P((const char * strp, struct rule * rulep)); 122 static void gmtload P((struct state * sp)); 123 static void gmtsub P((const time_t * timep, long offset, 124 struct tm * tmp)); 125 static void localsub P((const time_t * timep, long offset, 126 struct tm * tmp)); 127 static int increment_overflow P((int * number, int delta)); 128 static int normalize_overflow P((int * tensptr, int * unitsptr, 129 int base)); 130 static void settzname P((void)); 131 static time_t time1 P((struct tm * tmp, 132 void(*funcp) P((const time_t *, 133 long, struct tm *)), 134 long offset)); 135 static time_t time2 P((struct tm *tmp, 136 void(*funcp) P((const time_t *, 137 long, struct tm*)), 138 long offset, int * okayp)); 139 static void timesub P((const time_t * timep, long offset, 140 const struct state * sp, struct tm * tmp)); 141 static int tmcomp P((const struct tm * atmp, 142 const struct tm * btmp)); 143 static time_t transtime P((time_t janfirst, int year, 144 const struct rule * rulep, long offset)); 145 static int tzload P((const char * name, struct state * sp)); 146 static int tzparse P((const char * name, struct state * sp, 147 int lastditch)); 148 149 #ifdef ALL_STATE 150 static struct state * lclptr; 151 static struct state * gmtptr; 152 #endif /* defined ALL_STATE */ 153 154 #ifndef ALL_STATE 155 static struct state lclmem; 156 static struct state gmtmem; 157 #define lclptr (&lclmem) 158 #define gmtptr (&gmtmem) 159 #endif /* State Farm */ 160 161 #ifndef TZ_STRLEN_MAX 162 #define TZ_STRLEN_MAX 255 163 #endif /* !defined TZ_STRLEN_MAX */ 164 165 static char lcl_TZname[TZ_STRLEN_MAX + 1]; 166 static int lcl_is_set; 167 static int gmt_is_set; 168 169 char * tzname[2] = { 170 wildabbr, 171 wildabbr 172 }; 173 174 /* 175 ** Section 4.12.3 of X3.159-1989 requires that 176 ** Except for the strftime function, these functions [asctime, 177 ** ctime, gmtime, localtime] return values in one of two static 178 ** objects: a broken-down time structure and an array of char. 179 ** Thanks to Paul Eggert (eggert@twinsun.com) for noting this. 180 */ 181 182 static struct tm tm; 183 184 #ifdef USG_COMPAT 185 time_t timezone = 0; 186 int daylight = 0; 187 #endif /* defined USG_COMPAT */ 188 189 #ifdef ALTZONE 190 time_t altzone = 0; 191 #endif /* defined ALTZONE */ 192 193 static long 194 detzcode(codep) 195 const char * const codep; 196 { 197 register long result; 198 199 /* 200 ** The first character must be sign extended on systems with >32bit 201 ** longs. This was solved differently in the master tzcode sources 202 ** (the fix first appeared in tzcode95c.tar.gz). But I believe 203 ** that this implementation is superior. 204 */ 205 206 #ifdef __STDC__ 207 #define SIGN_EXTEND_CHAR(x) ((signed char) x) 208 #else 209 #define SIGN_EXTEND_CHAR(x) ((x & 0x80) ? ((~0 << 8) | x) : x) 210 #endif 211 212 result = (SIGN_EXTEND_CHAR(codep[0]) << 24) \ 213 | (codep[1] & 0xff) << 16 \ 214 | (codep[2] & 0xff) << 8 215 | (codep[3] & 0xff); 216 return result; 217 } 218 219 static void 220 settzname P((void)) 221 { 222 register struct state * const sp = lclptr; 223 register int i; 224 225 tzname[0] = wildabbr; 226 tzname[1] = wildabbr; 227 #ifdef USG_COMPAT 228 daylight = 0; 229 timezone = 0; 230 #endif /* defined USG_COMPAT */ 231 #ifdef ALTZONE 232 altzone = 0; 233 #endif /* defined ALTZONE */ 234 #ifdef ALL_STATE 235 if (sp == NULL) { 236 tzname[0] = tzname[1] = gmt; 237 return; 238 } 239 #endif /* defined ALL_STATE */ 240 for (i = 0; i < sp->typecnt; ++i) { 241 register const struct ttinfo * const ttisp = &sp->ttis[i]; 242 243 tzname[ttisp->tt_isdst] = 244 &sp->chars[ttisp->tt_abbrind]; 245 #ifdef USG_COMPAT 246 if (ttisp->tt_isdst) 247 daylight = 1; 248 if (i == 0 || !ttisp->tt_isdst) 249 timezone = -(ttisp->tt_gmtoff); 250 #endif /* defined USG_COMPAT */ 251 #ifdef ALTZONE 252 if (i == 0 || ttisp->tt_isdst) 253 altzone = -(ttisp->tt_gmtoff); 254 #endif /* defined ALTZONE */ 255 } 256 /* 257 ** And to get the latest zone names into tzname. . . 258 */ 259 for (i = 0; i < sp->timecnt; ++i) { 260 register const struct ttinfo * const ttisp = 261 &sp->ttis[ 262 sp->types[i]]; 263 264 tzname[ttisp->tt_isdst] = 265 &sp->chars[ttisp->tt_abbrind]; 266 } 267 } 268 269 static int 270 tzload(name, sp) 271 register const char * name; 272 register struct state * const sp; 273 { 274 register const char * p; 275 register int i; 276 register int fid; 277 278 if (name == NULL && (name = TZDEFAULT) == NULL) 279 return -1; 280 { 281 register int doaccess; 282 /* 283 ** Section 4.9.1 of the C standard says that 284 ** "FILENAME_MAX expands to an integral constant expression 285 ** that is the sie needed for an array of char large enough 286 ** to hold the longest file name string that the implementation 287 ** guarantees can be opened." 288 */ 289 char fullname[FILENAME_MAX + 1]; 290 291 if (name[0] == ':') 292 ++name; 293 doaccess = name[0] == '/'; 294 if (!doaccess) { 295 if ((p = TZDIR) == NULL) 296 return -1; 297 if ((strlen(p) + strlen(name) + 1) >= sizeof fullname) 298 return -1; 299 (void) strcpy(fullname, p); 300 (void) strcat(fullname, "/"); 301 (void) strcat(fullname, name); 302 /* 303 ** Set doaccess if '.' (as in "../") shows up in name. 304 */ 305 if (strchr(name, '.') != NULL) 306 doaccess = TRUE; 307 name = fullname; 308 } 309 if (doaccess && access(name, R_OK) != 0) 310 return -1; 311 if ((fid = open(name, OPEN_MODE)) == -1) 312 return -1; 313 } 314 { 315 struct tzhead * tzhp; 316 char buf[sizeof *sp + sizeof *tzhp]; 317 int ttisstdcnt; 318 int ttisgmtcnt; 319 320 i = read(fid, buf, sizeof buf); 321 if (close(fid) != 0) 322 return -1; 323 p = buf; 324 p += sizeof tzhp->tzh_reserved; 325 ttisstdcnt = (int) detzcode(p); 326 p += 4; 327 ttisgmtcnt = (int) detzcode(p); 328 p += 4; 329 sp->leapcnt = (int) detzcode(p); 330 p += 4; 331 sp->timecnt = (int) detzcode(p); 332 p += 4; 333 sp->typecnt = (int) detzcode(p); 334 p += 4; 335 sp->charcnt = (int) detzcode(p); 336 p += 4; 337 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS || 338 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES || 339 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES || 340 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS || 341 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) || 342 (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0)) 343 return -1; 344 if (i - (p - buf) < sp->timecnt * 4 + /* ats */ 345 sp->timecnt + /* types */ 346 sp->typecnt * (4 + 2) + /* ttinfos */ 347 sp->charcnt + /* chars */ 348 sp->leapcnt * (4 + 4) + /* lsinfos */ 349 ttisstdcnt + /* ttisstds */ 350 ttisgmtcnt) /* ttisgmts */ 351 return -1; 352 for (i = 0; i < sp->timecnt; ++i) { 353 sp->ats[i] = detzcode(p); 354 p += 4; 355 } 356 for (i = 0; i < sp->timecnt; ++i) { 357 sp->types[i] = (unsigned char) *p++; 358 if (sp->types[i] >= sp->typecnt) 359 return -1; 360 } 361 for (i = 0; i < sp->typecnt; ++i) { 362 register struct ttinfo * ttisp; 363 364 ttisp = &sp->ttis[i]; 365 ttisp->tt_gmtoff = detzcode(p); 366 p += 4; 367 ttisp->tt_isdst = (unsigned char) *p++; 368 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1) 369 return -1; 370 ttisp->tt_abbrind = (unsigned char) *p++; 371 if (ttisp->tt_abbrind < 0 || 372 ttisp->tt_abbrind > sp->charcnt) 373 return -1; 374 } 375 for (i = 0; i < sp->charcnt; ++i) 376 sp->chars[i] = *p++; 377 sp->chars[i] = '\0'; /* ensure '\0' at end */ 378 for (i = 0; i < sp->leapcnt; ++i) { 379 register struct lsinfo * lsisp; 380 381 lsisp = &sp->lsis[i]; 382 lsisp->ls_trans = detzcode(p); 383 p += 4; 384 lsisp->ls_corr = detzcode(p); 385 p += 4; 386 } 387 for (i = 0; i < sp->typecnt; ++i) { 388 register struct ttinfo * ttisp; 389 390 ttisp = &sp->ttis[i]; 391 if (ttisstdcnt == 0) 392 ttisp->tt_ttisstd = FALSE; 393 else { 394 ttisp->tt_ttisstd = *p++; 395 if (ttisp->tt_ttisstd != TRUE && 396 ttisp->tt_ttisstd != FALSE) 397 return -1; 398 } 399 } 400 for (i = 0; i < sp->typecnt; ++i) { 401 register struct ttinfo * ttisp; 402 403 ttisp = &sp->ttis[i]; 404 if (ttisgmtcnt == 0) 405 ttisp->tt_ttisgmt = FALSE; 406 else { 407 ttisp->tt_ttisgmt = *p++; 408 if (ttisp->tt_ttisgmt != TRUE && 409 ttisp->tt_ttisgmt != FALSE) 410 return -1; 411 } 412 } 413 } 414 return 0; 415 } 416 417 static const int mon_lengths[2][MONSPERYEAR] = { 418 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, 419 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } 420 }; 421 422 static const int year_lengths[2] = { 423 DAYSPERNYEAR, DAYSPERLYEAR 424 }; 425 426 /* 427 ** Given a pointer into a time zone string, scan until a character that is not 428 ** a valid character in a zone name is found. Return a pointer to that 429 ** character. 430 */ 431 432 static const char * 433 getzname(strp) 434 register const char * strp; 435 { 436 register char c; 437 438 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && 439 c != '+') 440 ++strp; 441 return strp; 442 } 443 444 /* 445 ** Given a pointer into a time zone string, extract a number from that string. 446 ** Check that the number is within a specified range; if it is not, return 447 ** NULL. 448 ** Otherwise, return a pointer to the first character not part of the number. 449 */ 450 451 static const char * 452 getnum(strp, nump, min, max) 453 register const char * strp; 454 int * const nump; 455 const int min; 456 const int max; 457 { 458 register char c; 459 register int num; 460 461 if (strp == NULL || !is_digit(c = *strp)) 462 return NULL; 463 num = 0; 464 do { 465 num = num * 10 + (c - '0'); 466 if (num > max) 467 return NULL; /* illegal value */ 468 c = *++strp; 469 } while (is_digit(c)); 470 if (num < min) 471 return NULL; /* illegal value */ 472 *nump = num; 473 return strp; 474 } 475 476 /* 477 ** Given a pointer into a time zone string, extract a number of seconds, 478 ** in hh[:mm[:ss]] form, from the string. 479 ** If any error occurs, return NULL. 480 ** Otherwise, return a pointer to the first character not part of the number 481 ** of seconds. 482 */ 483 484 static const char * 485 getsecs(strp, secsp) 486 register const char * strp; 487 long * const secsp; 488 { 489 int num; 490 491 /* 492 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like 493 ** "M10.4.6/26", which does not conform to Posix, 494 ** but which specifies the equivalent of 495 ** ``02:00 on the first Sunday on or after 23 Oct''. 496 */ 497 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); 498 if (strp == NULL) 499 return NULL; 500 *secsp = num * (long) SECSPERHOUR; 501 if (*strp == ':') { 502 ++strp; 503 strp = getnum(strp, &num, 0, MINSPERHOUR - 1); 504 if (strp == NULL) 505 return NULL; 506 *secsp += num * SECSPERMIN; 507 if (*strp == ':') { 508 ++strp; 509 /* `SECSPERMIN' allows for leap seconds. */ 510 strp = getnum(strp, &num, 0, SECSPERMIN); 511 if (strp == NULL) 512 return NULL; 513 *secsp += num; 514 } 515 } 516 return strp; 517 } 518 519 /* 520 ** Given a pointer into a time zone string, extract an offset, in 521 ** [+-]hh[:mm[:ss]] form, from the string. 522 ** If any error occurs, return NULL. 523 ** Otherwise, return a pointer to the first character not part of the time. 524 */ 525 526 static const char * 527 getoffset(strp, offsetp) 528 register const char * strp; 529 long * const offsetp; 530 { 531 register int neg = 0; 532 533 if (*strp == '-') { 534 neg = 1; 535 ++strp; 536 } else if (*strp == '+') 537 ++strp; 538 strp = getsecs(strp, offsetp); 539 if (strp == NULL) 540 return NULL; /* illegal time */ 541 if (neg) 542 *offsetp = -*offsetp; 543 return strp; 544 } 545 546 /* 547 ** Given a pointer into a time zone string, extract a rule in the form 548 ** date[/time]. See POSIX section 8 for the format of "date" and "time". 549 ** If a valid rule is not found, return NULL. 550 ** Otherwise, return a pointer to the first character not part of the rule. 551 */ 552 553 static const char * 554 getrule(strp, rulep) 555 const char * strp; 556 register struct rule * const rulep; 557 { 558 if (*strp == 'J') { 559 /* 560 ** Julian day. 561 */ 562 rulep->r_type = JULIAN_DAY; 563 ++strp; 564 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); 565 } else if (*strp == 'M') { 566 /* 567 ** Month, week, day. 568 */ 569 rulep->r_type = MONTH_NTH_DAY_OF_WEEK; 570 ++strp; 571 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); 572 if (strp == NULL) 573 return NULL; 574 if (*strp++ != '.') 575 return NULL; 576 strp = getnum(strp, &rulep->r_week, 1, 5); 577 if (strp == NULL) 578 return NULL; 579 if (*strp++ != '.') 580 return NULL; 581 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); 582 } else if (is_digit(*strp)) { 583 /* 584 ** Day of year. 585 */ 586 rulep->r_type = DAY_OF_YEAR; 587 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); 588 } else return NULL; /* invalid format */ 589 if (strp == NULL) 590 return NULL; 591 if (*strp == '/') { 592 /* 593 ** Time specified. 594 */ 595 ++strp; 596 strp = getsecs(strp, &rulep->r_time); 597 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ 598 return strp; 599 } 600 601 /* 602 ** Given the Epoch-relative time of January 1, 00:00:00 GMT, in a year, the 603 ** year, a rule, and the offset from GMT at the time that rule takes effect, 604 ** calculate the Epoch-relative time that rule takes effect. 605 */ 606 607 static time_t 608 transtime(janfirst, year, rulep, offset) 609 const time_t janfirst; 610 const int year; 611 register const struct rule * const rulep; 612 const long offset; 613 { 614 register int leapyear; 615 register time_t value; 616 register int i; 617 int d, m1, yy0, yy1, yy2, dow; 618 619 INITIALIZE(value); 620 leapyear = isleap(year); 621 switch (rulep->r_type) { 622 623 case JULIAN_DAY: 624 /* 625 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap 626 ** years. 627 ** In non-leap years, or if the day number is 59 or less, just 628 ** add SECSPERDAY times the day number-1 to the time of 629 ** January 1, midnight, to get the day. 630 */ 631 value = janfirst + (rulep->r_day - 1) * SECSPERDAY; 632 if (leapyear && rulep->r_day >= 60) 633 value += SECSPERDAY; 634 break; 635 636 case DAY_OF_YEAR: 637 /* 638 ** n - day of year. 639 ** Just add SECSPERDAY times the day number to the time of 640 ** January 1, midnight, to get the day. 641 */ 642 value = janfirst + rulep->r_day * SECSPERDAY; 643 break; 644 645 case MONTH_NTH_DAY_OF_WEEK: 646 /* 647 ** Mm.n.d - nth "dth day" of month m. 648 */ 649 value = janfirst; 650 for (i = 0; i < rulep->r_mon - 1; ++i) 651 value += mon_lengths[leapyear][i] * SECSPERDAY; 652 653 /* 654 ** Use Zeller's Congruence to get day-of-week of first day of 655 ** month. 656 */ 657 m1 = (rulep->r_mon + 9) % 12 + 1; 658 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; 659 yy1 = yy0 / 100; 660 yy2 = yy0 % 100; 661 dow = ((26 * m1 - 2) / 10 + 662 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; 663 if (dow < 0) 664 dow += DAYSPERWEEK; 665 666 /* 667 ** "dow" is the day-of-week of the first day of the month. Get 668 ** the day-of-month (zero-origin) of the first "dow" day of the 669 ** month. 670 */ 671 d = rulep->r_day - dow; 672 if (d < 0) 673 d += DAYSPERWEEK; 674 for (i = 1; i < rulep->r_week; ++i) { 675 if (d + DAYSPERWEEK >= 676 mon_lengths[leapyear][rulep->r_mon - 1]) 677 break; 678 d += DAYSPERWEEK; 679 } 680 681 /* 682 ** "d" is the day-of-month (zero-origin) of the day we want. 683 */ 684 value += d * SECSPERDAY; 685 break; 686 } 687 688 /* 689 ** "value" is the Epoch-relative time of 00:00:00 GMT on the day in 690 ** question. To get the Epoch-relative time of the specified local 691 ** time on that day, add the transition time and the current offset 692 ** from GMT. 693 */ 694 return value + rulep->r_time + offset; 695 } 696 697 /* 698 ** Given a POSIX section 8-style TZ string, fill in the rule tables as 699 ** appropriate. 700 */ 701 702 static int 703 tzparse(name, sp, lastditch) 704 const char * name; 705 register struct state * const sp; 706 const int lastditch; 707 { 708 const char * stdname; 709 const char * dstname; 710 size_t stdlen; 711 size_t dstlen; 712 long stdoffset; 713 long dstoffset; 714 register time_t * atp; 715 register unsigned char * typep; 716 register char * cp; 717 register int load_result; 718 719 INITIALIZE(dstname); 720 stdname = name; 721 if (lastditch) { 722 stdlen = strlen(name); /* length of standard zone name */ 723 name += stdlen; 724 if (stdlen >= sizeof sp->chars) 725 stdlen = (sizeof sp->chars) - 1; 726 } else { 727 name = getzname(name); 728 stdlen = name - stdname; 729 if (stdlen < 3) 730 return -1; 731 } 732 if (*name == '\0') 733 return -1; /* was "stdoffset = 0;" */ 734 else { 735 name = getoffset(name, &stdoffset); 736 if (name == NULL) 737 return -1; 738 } 739 load_result = tzload(TZDEFRULES, sp); 740 if (load_result != 0) 741 sp->leapcnt = 0; /* so, we're off a little */ 742 if (*name != '\0') { 743 dstname = name; 744 name = getzname(name); 745 dstlen = name - dstname; /* length of DST zone name */ 746 if (dstlen < 3) 747 return -1; 748 if (*name != '\0' && *name != ',' && *name != ';') { 749 name = getoffset(name, &dstoffset); 750 if (name == NULL) 751 return -1; 752 } else dstoffset = stdoffset - SECSPERHOUR; 753 if (*name == ',' || *name == ';') { 754 struct rule start; 755 struct rule end; 756 register int year; 757 register time_t janfirst; 758 time_t starttime; 759 time_t endtime; 760 761 ++name; 762 if ((name = getrule(name, &start)) == NULL) 763 return -1; 764 if (*name++ != ',') 765 return -1; 766 if ((name = getrule(name, &end)) == NULL) 767 return -1; 768 if (*name != '\0') 769 return -1; 770 sp->typecnt = 2; /* standard time and DST */ 771 /* 772 ** Two transitions per year, from EPOCH_YEAR to 2037. 773 */ 774 sp->timecnt = 2 * (2037 - EPOCH_YEAR + 1); 775 if (sp->timecnt > TZ_MAX_TIMES) 776 return -1; 777 sp->ttis[0].tt_gmtoff = -dstoffset; 778 sp->ttis[0].tt_isdst = 1; 779 sp->ttis[0].tt_abbrind = stdlen + 1; 780 sp->ttis[1].tt_gmtoff = -stdoffset; 781 sp->ttis[1].tt_isdst = 0; 782 sp->ttis[1].tt_abbrind = 0; 783 atp = sp->ats; 784 typep = sp->types; 785 janfirst = 0; 786 for (year = EPOCH_YEAR; year <= 2037; ++year) { 787 starttime = transtime(janfirst, year, &start, 788 stdoffset); 789 endtime = transtime(janfirst, year, &end, 790 dstoffset); 791 if (starttime > endtime) { 792 *atp++ = endtime; 793 *typep++ = 1; /* DST ends */ 794 *atp++ = starttime; 795 *typep++ = 0; /* DST begins */ 796 } else { 797 *atp++ = starttime; 798 *typep++ = 0; /* DST begins */ 799 *atp++ = endtime; 800 *typep++ = 1; /* DST ends */ 801 } 802 janfirst += year_lengths[isleap(year)] * 803 SECSPERDAY; 804 } 805 } else { 806 register long theirstdoffset; 807 register long theirdstoffset; 808 register long theiroffset; 809 register int isdst; 810 register int i; 811 register int j; 812 813 if (*name != '\0') 814 return -1; 815 if (load_result != 0) 816 return -1; 817 /* 818 ** Initial values of theirstdoffset and theirdstoffset. 819 */ 820 theirstdoffset = 0; 821 for (i = 0; i < sp->timecnt; ++i) { 822 j = sp->types[i]; 823 if (!sp->ttis[j].tt_isdst) { 824 theirstdoffset = 825 -sp->ttis[j].tt_gmtoff; 826 break; 827 } 828 } 829 theirdstoffset = 0; 830 for (i = 0; i < sp->timecnt; ++i) { 831 j = sp->types[i]; 832 if (sp->ttis[j].tt_isdst) { 833 theirdstoffset = 834 -sp->ttis[j].tt_gmtoff; 835 break; 836 } 837 } 838 /* 839 ** Initially we're assumed to be in standard time. 840 */ 841 isdst = FALSE; 842 theiroffset = theirstdoffset; 843 /* 844 ** Now juggle transition times and types 845 ** tracking offsets as you do. 846 */ 847 for (i = 0; i < sp->timecnt; ++i) { 848 j = sp->types[i]; 849 sp->types[i] = sp->ttis[j].tt_isdst; 850 if (sp->ttis[j].tt_ttisgmt) { 851 /* No adjustment to transition time */ 852 } else { 853 /* 854 ** If summer time is in effect, and the 855 ** transition time was not specified as 856 ** standard time, add the summer time 857 ** offset to the transition time; 858 ** otherwise, add the standard time 859 ** offset to the transition time. 860 */ 861 /* 862 ** Transitions from DST to DDST 863 ** will effectively disappear since 864 ** POSIX provides for only one DST 865 ** offset. 866 */ 867 if (isdst && !sp->ttis[j].tt_ttisstd) { 868 sp->ats[i] += dstoffset - 869 theirdstoffset; 870 } else { 871 sp->ats[i] += stdoffset - 872 theirstdoffset; 873 } 874 } 875 theiroffset = -sp->ttis[j].tt_gmtoff; 876 if (sp->ttis[j].tt_isdst) 877 theirdstoffset = theiroffset; 878 else theirstdoffset = theiroffset; 879 } 880 /* 881 ** Finally, fill in ttis. 882 ** ttisstd and ttisgmt need not be handled. 883 */ 884 sp->ttis[0].tt_gmtoff = -stdoffset; 885 sp->ttis[0].tt_isdst = FALSE; 886 sp->ttis[0].tt_abbrind = 0; 887 sp->ttis[1].tt_gmtoff = -dstoffset; 888 sp->ttis[1].tt_isdst = TRUE; 889 sp->ttis[1].tt_abbrind = stdlen + 1; 890 sp->typecnt = 2; 891 } 892 } else { 893 dstlen = 0; 894 sp->typecnt = 1; /* only standard time */ 895 sp->timecnt = 0; 896 sp->ttis[0].tt_gmtoff = -stdoffset; 897 sp->ttis[0].tt_isdst = 0; 898 sp->ttis[0].tt_abbrind = 0; 899 } 900 sp->charcnt = stdlen + 1; 901 if (dstlen != 0) 902 sp->charcnt += dstlen + 1; 903 if (sp->charcnt > sizeof sp->chars) 904 return -1; 905 cp = sp->chars; 906 (void) strncpy(cp, stdname, stdlen); 907 cp += stdlen; 908 *cp++ = '\0'; 909 if (dstlen != 0) { 910 (void) strncpy(cp, dstname, dstlen); 911 *(cp + dstlen) = '\0'; 912 } 913 return 0; 914 } 915 916 static void 917 gmtload(sp) 918 struct state * const sp; 919 { 920 if (tzload(gmt, sp) != 0) 921 (void) tzparse(gmt, sp, TRUE); 922 } 923 924 #ifndef STD_INSPIRED 925 /* 926 ** A non-static declaration of tzsetwall in a system header file 927 ** may cause a warning about this upcoming static declaration... 928 */ 929 static 930 #endif /* !defined STD_INSPIRED */ 931 void 932 tzsetwall P((void)) 933 { 934 if (lcl_is_set < 0) 935 return; 936 lcl_is_set = -1; 937 938 #ifdef ALL_STATE 939 if (lclptr == NULL) { 940 lclptr = (struct state *) malloc(sizeof *lclptr); 941 if (lclptr == NULL) { 942 settzname(); /* all we can do */ 943 return; 944 } 945 } 946 #endif /* defined ALL_STATE */ 947 if (tzload((char *) NULL, lclptr) != 0) 948 gmtload(lclptr); 949 settzname(); 950 } 951 952 void 953 tzset P((void)) 954 { 955 register const char * name; 956 957 name = getenv("TZ"); 958 if (name == NULL) { 959 tzsetwall(); 960 return; 961 } 962 963 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) 964 return; 965 lcl_is_set = (strlen(name) < sizeof(lcl_TZname)); 966 if (lcl_is_set) 967 (void) strcpy(lcl_TZname, name); 968 969 #ifdef ALL_STATE 970 if (lclptr == NULL) { 971 lclptr = (struct state *) malloc(sizeof *lclptr); 972 if (lclptr == NULL) { 973 settzname(); /* all we can do */ 974 return; 975 } 976 } 977 #endif /* defined ALL_STATE */ 978 if (*name == '\0') { 979 /* 980 ** User wants it fast rather than right. 981 */ 982 lclptr->leapcnt = 0; /* so, we're off a little */ 983 lclptr->timecnt = 0; 984 lclptr->ttis[0].tt_gmtoff = 0; 985 lclptr->ttis[0].tt_abbrind = 0; 986 (void) strcpy(lclptr->chars, gmt); 987 } else if (tzload(name, lclptr) != 0) 988 if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0) 989 (void) gmtload(lclptr); 990 settzname(); 991 } 992 993 /* 994 ** The easy way to behave "as if no library function calls" localtime 995 ** is to not call it--so we drop its guts into "localsub", which can be 996 ** freely called. (And no, the PANS doesn't require the above behavior-- 997 ** but it *is* desirable.) 998 ** 999 ** The unused offset argument is for the benefit of mktime variants. 1000 */ 1001 1002 /*ARGSUSED*/ 1003 static void 1004 localsub(timep, offset, tmp) 1005 const time_t * const timep; 1006 const long offset; 1007 struct tm * const tmp; 1008 { 1009 register struct state * sp; 1010 register const struct ttinfo * ttisp; 1011 register int i; 1012 const time_t t = *timep; 1013 1014 sp = lclptr; 1015 #ifdef ALL_STATE 1016 if (sp == NULL) { 1017 gmtsub(timep, offset, tmp); 1018 return; 1019 } 1020 #endif /* defined ALL_STATE */ 1021 if (sp->timecnt == 0 || t < sp->ats[0]) { 1022 i = 0; 1023 while (sp->ttis[i].tt_isdst) 1024 if (++i >= sp->typecnt) { 1025 i = 0; 1026 break; 1027 } 1028 } else { 1029 for (i = 1; i < sp->timecnt; ++i) 1030 if (t < sp->ats[i]) 1031 break; 1032 i = sp->types[i - 1]; 1033 } 1034 ttisp = &sp->ttis[i]; 1035 /* 1036 ** To get (wrong) behavior that's compatible with System V Release 2.0 1037 ** you'd replace the statement below with 1038 ** t += ttisp->tt_gmtoff; 1039 ** timesub(&t, 0L, sp, tmp); 1040 */ 1041 timesub(&t, ttisp->tt_gmtoff, sp, tmp); 1042 tmp->tm_isdst = ttisp->tt_isdst; 1043 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind]; 1044 #ifdef TM_ZONE 1045 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind]; 1046 #endif /* defined TM_ZONE */ 1047 } 1048 1049 struct tm * 1050 localtime(timep) 1051 const time_t * const timep; 1052 { 1053 tzset(); 1054 localsub(timep, 0L, &tm); 1055 return &tm; 1056 } 1057 1058 /* 1059 ** gmtsub is to gmtime as localsub is to localtime. 1060 */ 1061 1062 static void 1063 gmtsub(timep, offset, tmp) 1064 const time_t * const timep; 1065 const long offset; 1066 struct tm * const tmp; 1067 { 1068 if (!gmt_is_set) { 1069 gmt_is_set = TRUE; 1070 #ifdef ALL_STATE 1071 gmtptr = (struct state *) malloc(sizeof *gmtptr); 1072 if (gmtptr != NULL) 1073 #endif /* defined ALL_STATE */ 1074 gmtload(gmtptr); 1075 } 1076 timesub(timep, offset, gmtptr, tmp); 1077 #ifdef TM_ZONE 1078 /* 1079 ** Could get fancy here and deliver something such as 1080 ** "GMT+xxxx" or "GMT-xxxx" if offset is non-zero, 1081 ** but this is no time for a treasure hunt. 1082 */ 1083 if (offset != 0) 1084 tmp->TM_ZONE = wildabbr; 1085 else { 1086 #ifdef ALL_STATE 1087 if (gmtptr == NULL) 1088 tmp->TM_ZONE = gmt; 1089 else tmp->TM_ZONE = gmtptr->chars; 1090 #endif /* defined ALL_STATE */ 1091 #ifndef ALL_STATE 1092 tmp->TM_ZONE = gmtptr->chars; 1093 #endif /* State Farm */ 1094 } 1095 #endif /* defined TM_ZONE */ 1096 } 1097 1098 struct tm * 1099 gmtime(timep) 1100 const time_t * const timep; 1101 { 1102 gmtsub(timep, 0L, &tm); 1103 return &tm; 1104 } 1105 1106 #ifdef STD_INSPIRED 1107 1108 struct tm * 1109 offtime(timep, offset) 1110 const time_t * const timep; 1111 const long offset; 1112 { 1113 gmtsub(timep, offset, &tm); 1114 return &tm; 1115 } 1116 1117 #endif /* defined STD_INSPIRED */ 1118 1119 static void 1120 timesub(timep, offset, sp, tmp) 1121 const time_t * const timep; 1122 const long offset; 1123 register const struct state * const sp; 1124 register struct tm * const tmp; 1125 { 1126 register const struct lsinfo * lp; 1127 register long days; 1128 register long rem; 1129 register int y; 1130 register int yleap; 1131 register const int * ip; 1132 register long corr; 1133 register int hit; 1134 register int i; 1135 1136 corr = 0; 1137 hit = 0; 1138 #ifdef ALL_STATE 1139 i = (sp == NULL) ? 0 : sp->leapcnt; 1140 #endif /* defined ALL_STATE */ 1141 #ifndef ALL_STATE 1142 i = sp->leapcnt; 1143 #endif /* State Farm */ 1144 while (--i >= 0) { 1145 lp = &sp->lsis[i]; 1146 if (*timep >= lp->ls_trans) { 1147 if (*timep == lp->ls_trans) { 1148 hit = ((i == 0 && lp->ls_corr > 0) || 1149 lp->ls_corr > sp->lsis[i - 1].ls_corr); 1150 if (hit) 1151 while (i > 0 && 1152 sp->lsis[i].ls_trans == 1153 sp->lsis[i - 1].ls_trans + 1 && 1154 sp->lsis[i].ls_corr == 1155 sp->lsis[i - 1].ls_corr + 1) { 1156 ++hit; 1157 --i; 1158 } 1159 } 1160 corr = lp->ls_corr; 1161 break; 1162 } 1163 } 1164 days = *timep / SECSPERDAY; 1165 rem = *timep % SECSPERDAY; 1166 #ifdef mc68k 1167 if (*timep == 0x80000000) { 1168 /* 1169 ** A 3B1 muffs the division on the most negative number. 1170 */ 1171 days = -24855; 1172 rem = -11648; 1173 } 1174 #endif /* defined mc68k */ 1175 rem += (offset - corr); 1176 while (rem < 0) { 1177 rem += SECSPERDAY; 1178 --days; 1179 } 1180 while (rem >= SECSPERDAY) { 1181 rem -= SECSPERDAY; 1182 ++days; 1183 } 1184 tmp->tm_hour = (int) (rem / SECSPERHOUR); 1185 rem = rem % SECSPERHOUR; 1186 tmp->tm_min = (int) (rem / SECSPERMIN); 1187 /* 1188 ** A positive leap second requires a special 1189 ** representation. This uses "... ??:59:60" et seq. 1190 */ 1191 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit; 1192 tmp->tm_wday = (int) ((EPOCH_WDAY + days) % DAYSPERWEEK); 1193 if (tmp->tm_wday < 0) 1194 tmp->tm_wday += DAYSPERWEEK; 1195 y = EPOCH_YEAR; 1196 #define LEAPS_THRU_END_OF(y) ((y) / 4 - (y) / 100 + (y) / 400) 1197 while (days < 0 || days >= (long) year_lengths[yleap = isleap(y)]) { 1198 register int newy; 1199 1200 newy = y + days / DAYSPERNYEAR; 1201 if (days < 0) 1202 --newy; 1203 days -= (newy - y) * DAYSPERNYEAR + 1204 LEAPS_THRU_END_OF(newy - 1) - 1205 LEAPS_THRU_END_OF(y - 1); 1206 y = newy; 1207 } 1208 tmp->tm_year = y - TM_YEAR_BASE; 1209 tmp->tm_yday = (int) days; 1210 ip = mon_lengths[yleap]; 1211 for (tmp->tm_mon = 0; days >= (long) ip[tmp->tm_mon]; ++(tmp->tm_mon)) 1212 days = days - (long) ip[tmp->tm_mon]; 1213 tmp->tm_mday = (int) (days + 1); 1214 tmp->tm_isdst = 0; 1215 #ifdef TM_GMTOFF 1216 tmp->TM_GMTOFF = offset; 1217 #endif /* defined TM_GMTOFF */ 1218 } 1219 1220 char * 1221 ctime(timep) 1222 const time_t * const timep; 1223 { 1224 /* 1225 ** Section 4.12.3.2 of X3.159-1989 requires that 1226 ** The ctime funciton converts the calendar time pointed to by timer 1227 ** to local time in the form of a string. It is equivalent to 1228 ** asctime(localtime(timer)) 1229 */ 1230 return asctime(localtime(timep)); 1231 } 1232 1233 /* 1234 ** Adapted from code provided by Robert Elz, who writes: 1235 ** The "best" way to do mktime I think is based on an idea of Bob 1236 ** Kridle's (so its said...) from a long time ago. 1237 ** [kridle@xinet.com as of 1996-01-16.] 1238 ** It does a binary search of the time_t space. Since time_t's are 1239 ** just 32 bits, its a max of 32 iterations (even at 64 bits it 1240 ** would still be very reasonable). 1241 */ 1242 1243 #ifndef WRONG 1244 #define WRONG (-1) 1245 #endif /* !defined WRONG */ 1246 1247 /* 1248 ** Simplified normalize logic courtesy Paul Eggert (eggert@twinsun.com). 1249 */ 1250 1251 static int 1252 increment_overflow(number, delta) 1253 int * number; 1254 int delta; 1255 { 1256 int number0; 1257 1258 number0 = *number; 1259 *number += delta; 1260 return (*number < number0) != (delta < 0); 1261 } 1262 1263 static int 1264 normalize_overflow(tensptr, unitsptr, base) 1265 int * const tensptr; 1266 int * const unitsptr; 1267 const int base; 1268 { 1269 register int tensdelta; 1270 1271 tensdelta = (*unitsptr >= 0) ? 1272 (*unitsptr / base) : 1273 (-1 - (-1 - *unitsptr) / base); 1274 *unitsptr -= tensdelta * base; 1275 return increment_overflow(tensptr, tensdelta); 1276 } 1277 1278 static int 1279 tmcomp(atmp, btmp) 1280 register const struct tm * const atmp; 1281 register const struct tm * const btmp; 1282 { 1283 register int result; 1284 1285 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 && 1286 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 && 1287 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && 1288 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && 1289 (result = (atmp->tm_min - btmp->tm_min)) == 0) 1290 result = atmp->tm_sec - btmp->tm_sec; 1291 return result; 1292 } 1293 1294 static time_t 1295 time2(tmp, funcp, offset, okayp) 1296 struct tm * const tmp; 1297 void (* const funcp) P((const time_t*, long, struct tm*)); 1298 const long offset; 1299 int * const okayp; 1300 { 1301 register const struct state * sp; 1302 register int dir; 1303 register int bits; 1304 register int i, j ; 1305 register int saved_seconds; 1306 time_t newt; 1307 time_t t; 1308 struct tm yourtm, mytm; 1309 1310 *okayp = FALSE; 1311 yourtm = *tmp; 1312 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) 1313 return WRONG; 1314 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) 1315 return WRONG; 1316 if (normalize_overflow(&yourtm.tm_year, &yourtm.tm_mon, MONSPERYEAR)) 1317 return WRONG; 1318 /* 1319 ** Turn yourtm.tm_year into an actual year number for now. 1320 ** It is converted back to an offset from TM_YEAR_BASE later. 1321 */ 1322 if (increment_overflow(&yourtm.tm_year, TM_YEAR_BASE)) 1323 return WRONG; 1324 while (yourtm.tm_mday <= 0) { 1325 if (increment_overflow(&yourtm.tm_year, -1)) 1326 return WRONG; 1327 i = yourtm.tm_year + (1 < yourtm.tm_mon); 1328 yourtm.tm_mday += year_lengths[isleap(i)]; 1329 } 1330 while (yourtm.tm_mday > DAYSPERLYEAR) { 1331 i = yourtm.tm_year + (1 < yourtm.tm_mon); 1332 yourtm.tm_mday -= year_lengths[isleap(i)]; 1333 if (increment_overflow(&yourtm.tm_year, 1)) 1334 return WRONG; 1335 } 1336 for ( ; ; ) { 1337 i = mon_lengths[isleap(yourtm.tm_year)][yourtm.tm_mon]; 1338 if (yourtm.tm_mday <= i) 1339 break; 1340 yourtm.tm_mday -= i; 1341 if (++yourtm.tm_mon >= MONSPERYEAR) { 1342 yourtm.tm_mon = 0; 1343 if (increment_overflow(&yourtm.tm_year, 1)) 1344 return WRONG; 1345 } 1346 } 1347 if (increment_overflow(&yourtm.tm_year, -TM_YEAR_BASE)) 1348 return WRONG; 1349 if (yourtm.tm_year + TM_YEAR_BASE < EPOCH_YEAR) { 1350 /* 1351 ** We can't set tm_sec to 0, because that might push the 1352 ** time below the minimum representable time. 1353 ** Set tm_sec to 59 instead. 1354 ** This assumes that the minimum representable time is 1355 ** not in the same minute that a leap second was deleted from, 1356 ** which is a safer assumption than using 58 would be. 1357 */ 1358 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) 1359 return WRONG; 1360 saved_seconds = yourtm.tm_sec; 1361 yourtm.tm_sec = SECSPERMIN - 1; 1362 } else { 1363 saved_seconds = yourtm.tm_sec; 1364 yourtm.tm_sec = 0; 1365 } 1366 /* 1367 ** Divide the search space in half 1368 ** (this works whether time_t is signed or unsigned). 1369 */ 1370 bits = TYPE_BIT(time_t) - 1; 1371 /* 1372 ** If time_t is signed, then 0 is just above the median, 1373 ** assuming two's complement arithmetic. 1374 ** If time_t is unsigned, then (1 << bits) is just above the median. 1375 */ 1376 t = TYPE_SIGNED(time_t) ? 0 : (((time_t) 1) << bits); 1377 for ( ; ; ) { 1378 (*funcp)(&t, offset, &mytm); 1379 dir = tmcomp(&mytm, &yourtm); 1380 if (dir != 0) { 1381 if (bits-- < 0) 1382 return WRONG; 1383 if (bits < 0) 1384 --t; /* may be needed if new t is minimal */ 1385 else if (dir > 0) 1386 t -= ((time_t) 1) << bits; 1387 else t += ((time_t) 1) << bits; 1388 continue; 1389 } 1390 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) 1391 break; 1392 /* 1393 ** Right time, wrong type. 1394 ** Hunt for right time, right type. 1395 ** It's okay to guess wrong since the guess 1396 ** gets checked. 1397 */ 1398 /* 1399 ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's. 1400 */ 1401 sp = (const struct state *) 1402 (((void *) funcp == (void *) localsub) ? 1403 lclptr : gmtptr); 1404 #ifdef ALL_STATE 1405 if (sp == NULL) 1406 return WRONG; 1407 #endif /* defined ALL_STATE */ 1408 for (i = sp->typecnt - 1; i >= 0; --i) { 1409 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) 1410 continue; 1411 for (j = sp->typecnt - 1; j >= 0; --j) { 1412 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) 1413 continue; 1414 newt = t + sp->ttis[j].tt_gmtoff - 1415 sp->ttis[i].tt_gmtoff; 1416 (*funcp)(&newt, offset, &mytm); 1417 if (tmcomp(&mytm, &yourtm) != 0) 1418 continue; 1419 if (mytm.tm_isdst != yourtm.tm_isdst) 1420 continue; 1421 /* 1422 ** We have a match. 1423 */ 1424 t = newt; 1425 goto label; 1426 } 1427 } 1428 return WRONG; 1429 } 1430 label: 1431 newt = t + saved_seconds; 1432 if ((newt < t) != (saved_seconds < 0)) 1433 return WRONG; 1434 t = newt; 1435 (*funcp)(&t, offset, tmp); 1436 *okayp = TRUE; 1437 return t; 1438 } 1439 1440 static time_t 1441 time1(tmp, funcp, offset) 1442 struct tm * const tmp; 1443 void (* const funcp) P((const time_t *, long, struct tm *)); 1444 const long offset; 1445 { 1446 register time_t t; 1447 register const struct state * sp; 1448 register int samei, otheri; 1449 int okay; 1450 1451 if (tmp->tm_isdst > 1) 1452 tmp->tm_isdst = 1; 1453 t = time2(tmp, funcp, offset, &okay); 1454 #ifdef PCTS 1455 /* 1456 ** PCTS code courtesy Grant Sullivan (grant@osf.org). 1457 */ 1458 if (okay) 1459 return t; 1460 if (tmp->tm_isdst < 0) 1461 tmp->tm_isdst = 0; /* reset to std and try again */ 1462 #endif /* defined PCTS */ 1463 #ifndef PCTS 1464 if (okay || tmp->tm_isdst < 0) 1465 return t; 1466 #endif /* !defined PCTS */ 1467 /* 1468 ** We're supposed to assume that somebody took a time of one type 1469 ** and did some math on it that yielded a "struct tm" that's bad. 1470 ** We try to divine the type they started from and adjust to the 1471 ** type they need. 1472 */ 1473 /* 1474 ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's. 1475 */ 1476 sp = (const struct state *) (((void *) funcp == (void *) localsub) ? 1477 lclptr : gmtptr); 1478 #ifdef ALL_STATE 1479 if (sp == NULL) 1480 return WRONG; 1481 #endif /* defined ALL_STATE */ 1482 for (samei = sp->typecnt - 1; samei >= 0; --samei) { 1483 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) 1484 continue; 1485 for (otheri = sp->typecnt - 1; otheri >= 0; --otheri) { 1486 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) 1487 continue; 1488 tmp->tm_sec += sp->ttis[otheri].tt_gmtoff - 1489 sp->ttis[samei].tt_gmtoff; 1490 tmp->tm_isdst = !tmp->tm_isdst; 1491 t = time2(tmp, funcp, offset, &okay); 1492 if (okay) 1493 return t; 1494 tmp->tm_sec -= sp->ttis[otheri].tt_gmtoff - 1495 sp->ttis[samei].tt_gmtoff; 1496 tmp->tm_isdst = !tmp->tm_isdst; 1497 } 1498 } 1499 return WRONG; 1500 } 1501 1502 time_t 1503 mktime(tmp) 1504 struct tm * const tmp; 1505 { 1506 tzset(); 1507 return time1(tmp, localsub, 0L); 1508 } 1509 1510 #ifdef STD_INSPIRED 1511 1512 time_t 1513 timelocal(tmp) 1514 struct tm * const tmp; 1515 { 1516 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 1517 return mktime(tmp); 1518 } 1519 1520 time_t 1521 timegm(tmp) 1522 struct tm * const tmp; 1523 { 1524 tmp->tm_isdst = 0; 1525 return time1(tmp, gmtsub, 0L); 1526 } 1527 1528 time_t 1529 timeoff(tmp, offset) 1530 struct tm * const tmp; 1531 const long offset; 1532 { 1533 tmp->tm_isdst = 0; 1534 return time1(tmp, gmtsub, offset); 1535 } 1536 1537 #endif /* defined STD_INSPIRED */ 1538 1539 #ifdef CMUCS 1540 1541 /* 1542 ** The following is supplied for compatibility with 1543 ** previous versions of the CMUCS runtime library. 1544 */ 1545 1546 long 1547 gtime(tmp) 1548 struct tm * const tmp; 1549 { 1550 const time_t t = mktime(tmp); 1551 1552 if (t == WRONG) 1553 return -1; 1554 return t; 1555 } 1556 1557 #endif /* defined CMUCS */ 1558 1559 /* 1560 ** XXX--is the below the right way to conditionalize?? 1561 */ 1562 1563 #ifdef STD_INSPIRED 1564 1565 /* 1566 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 1567 ** shall correspond to "Wed Dec 31 23:59:59 GMT 1986", which 1568 ** is not the case if we are accounting for leap seconds. 1569 ** So, we provide the following conversion routines for use 1570 ** when exchanging timestamps with POSIX conforming systems. 1571 */ 1572 1573 static long 1574 leapcorr(timep) 1575 time_t * timep; 1576 { 1577 register struct state * sp; 1578 register struct lsinfo * lp; 1579 register int i; 1580 1581 sp = lclptr; 1582 i = sp->leapcnt; 1583 while (--i >= 0) { 1584 lp = &sp->lsis[i]; 1585 if (*timep >= lp->ls_trans) 1586 return lp->ls_corr; 1587 } 1588 return 0; 1589 } 1590 1591 time_t 1592 time2posix(t) 1593 time_t t; 1594 { 1595 tzset(); 1596 return t - leapcorr(&t); 1597 } 1598 1599 time_t 1600 posix2time(t) 1601 time_t t; 1602 { 1603 time_t x; 1604 time_t y; 1605 1606 tzset(); 1607 /* 1608 ** For a positive leap second hit, the result 1609 ** is not unique. For a negative leap second 1610 ** hit, the corresponding time doesn't exist, 1611 ** so we return an adjacent second. 1612 */ 1613 x = t + leapcorr(&t); 1614 y = x - leapcorr(&x); 1615 if (y < t) { 1616 do { 1617 x++; 1618 y = x - leapcorr(&x); 1619 } while (y < t); 1620 if (t != y) 1621 return x - 1; 1622 } else if (y > t) { 1623 do { 1624 --x; 1625 y = x - leapcorr(&x); 1626 } while (y > t); 1627 if (t != y) 1628 return x + 1; 1629 } 1630 return x; 1631 } 1632 1633 #endif /* defined STD_INSPIRED */ 1634