1 /* $NetBSD: localtime.c,v 1.28 2001/11/04 13:57:31 lukem Exp $ */ 2 3 /* 4 ** This file is in the public domain, so clarified as of 5 ** 1996-06-05 by Arthur David Olson (arthur_david_olson@nih.gov). 6 */ 7 8 #include <sys/cdefs.h> 9 #if defined(LIBC_SCCS) && !defined(lint) 10 #if 0 11 static char elsieid[] = "@(#)localtime.c 7.70"; 12 #else 13 __RCSID("$NetBSD: localtime.c,v 1.28 2001/11/04 13:57:31 lukem Exp $"); 14 #endif 15 #endif /* LIBC_SCCS and not lint */ 16 17 /* 18 ** Leap second handling from Bradley White (bww@k.gp.cs.cmu.edu). 19 ** POSIX-style TZ environment variable handling from Guy Harris 20 ** (guy@auspex.com). 21 */ 22 23 /*LINTLIBRARY*/ 24 25 #include "namespace.h" 26 #include "private.h" 27 #include "tzfile.h" 28 #include "fcntl.h" 29 #include "reentrant.h" 30 31 #ifdef __weak_alias 32 __weak_alias(ctime_r,_ctime_r) 33 __weak_alias(daylight,_daylight) 34 __weak_alias(gmtime_r,_gmtime_r) 35 __weak_alias(localtime_r,_localtime_r) 36 __weak_alias(offtime,_offtime) 37 __weak_alias(posix2time,_posix2time) 38 __weak_alias(time2posix,_time2posix) 39 __weak_alias(timegm,_timegm) 40 __weak_alias(timelocal,_timelocal) 41 __weak_alias(timeoff,_timeoff) 42 __weak_alias(tzname,_tzname) 43 __weak_alias(tzset,_tzset) 44 __weak_alias(tzsetwall,_tzsetwall) 45 #endif 46 47 /* 48 ** SunOS 4.1.1 headers lack O_BINARY. 49 */ 50 51 #ifdef O_BINARY 52 #define OPEN_MODE (O_RDONLY | O_BINARY) 53 #endif /* defined O_BINARY */ 54 #ifndef O_BINARY 55 #define OPEN_MODE O_RDONLY 56 #endif /* !defined O_BINARY */ 57 58 #ifndef WILDABBR 59 /* 60 ** Someone might make incorrect use of a time zone abbreviation: 61 ** 1. They might reference tzname[0] before calling tzset (explicitly 62 ** or implicitly). 63 ** 2. They might reference tzname[1] before calling tzset (explicitly 64 ** or implicitly). 65 ** 3. They might reference tzname[1] after setting to a time zone 66 ** in which Daylight Saving Time is never observed. 67 ** 4. They might reference tzname[0] after setting to a time zone 68 ** in which Standard Time is never observed. 69 ** 5. They might reference tm.TM_ZONE after calling offtime. 70 ** What's best to do in the above cases is open to debate; 71 ** for now, we just set things up so that in any of the five cases 72 ** WILDABBR is used. Another possibility: initialize tzname[0] to the 73 ** string "tzname[0] used before set", and similarly for the other cases. 74 ** And another: initialize tzname[0] to "ERA", with an explanation in the 75 ** manual page of what this "time zone abbreviation" means (doing this so 76 ** that tzname[0] has the "normal" length of three characters). 77 */ 78 #define WILDABBR " " 79 #endif /* !defined WILDABBR */ 80 81 static const char wildabbr[] = "WILDABBR"; 82 83 static const char gmt[] = "GMT"; 84 85 /* 86 ** The DST rules to use if TZ has no rules and we can't load TZDEFRULES. 87 ** We default to US rules as of 1999-08-17. 88 ** POSIX 1003.1 section 8.1.1 says that the default DST rules are 89 ** implementation dependent; for historical reasons, US rules are a 90 ** common default. 91 */ 92 #ifndef TZDEFRULESTRING 93 #define TZDEFRULESTRING ",M4.1.0,M10.5.0" 94 #endif /* !defined TZDEFDST */ 95 96 struct ttinfo { /* time type information */ 97 long tt_gmtoff; /* UTC offset in seconds */ 98 int tt_isdst; /* used to set tm_isdst */ 99 int tt_abbrind; /* abbreviation list index */ 100 int tt_ttisstd; /* TRUE if transition is std time */ 101 int tt_ttisgmt; /* TRUE if transition is UTC */ 102 }; 103 104 struct lsinfo { /* leap second information */ 105 time_t ls_trans; /* transition time */ 106 long ls_corr; /* correction to apply */ 107 }; 108 109 #define BIGGEST(a, b) (((a) > (b)) ? (a) : (b)) 110 111 #ifdef TZNAME_MAX 112 #define MY_TZNAME_MAX TZNAME_MAX 113 #endif /* defined TZNAME_MAX */ 114 #ifndef TZNAME_MAX 115 #define MY_TZNAME_MAX 255 116 #endif /* !defined TZNAME_MAX */ 117 118 struct state { 119 int leapcnt; 120 int timecnt; 121 int typecnt; 122 int charcnt; 123 time_t ats[TZ_MAX_TIMES]; 124 unsigned char types[TZ_MAX_TIMES]; 125 struct ttinfo ttis[TZ_MAX_TYPES]; 126 char chars[/* LINTED constant */BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt), 127 (2 * (MY_TZNAME_MAX + 1)))]; 128 struct lsinfo lsis[TZ_MAX_LEAPS]; 129 }; 130 131 struct rule { 132 int r_type; /* type of rule--see below */ 133 int r_day; /* day number of rule */ 134 int r_week; /* week number of rule */ 135 int r_mon; /* month number of rule */ 136 long r_time; /* transition time of rule */ 137 }; 138 139 #define JULIAN_DAY 0 /* Jn - Julian day */ 140 #define DAY_OF_YEAR 1 /* n - day of year */ 141 #define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */ 142 143 /* 144 ** Prototypes for static functions. 145 */ 146 147 static long detzcode P((const char * codep)); 148 static const char * getzname P((const char * strp)); 149 static const char * getnum P((const char * strp, int * nump, int min, 150 int max)); 151 static const char * getsecs P((const char * strp, long * secsp)); 152 static const char * getoffset P((const char * strp, long * offsetp)); 153 static const char * getrule P((const char * strp, struct rule * rulep)); 154 static void gmtload P((struct state * sp)); 155 static void gmtsub P((const time_t * timep, long offset, 156 struct tm * tmp)); 157 static void localsub P((const time_t * timep, long offset, 158 struct tm * tmp)); 159 static int increment_overflow P((int * number, int delta)); 160 static int normalize_overflow P((int * tensptr, int * unitsptr, 161 int base)); 162 static void settzname P((void)); 163 static time_t time1 P((struct tm * tmp, 164 void(*funcp) P((const time_t *, 165 long, struct tm *)), 166 long offset)); 167 static time_t time2 P((struct tm *tmp, 168 void(*funcp) P((const time_t *, 169 long, struct tm*)), 170 long offset, int * okayp)); 171 static time_t time2sub P((struct tm *tmp, 172 void(*funcp) P((const time_t *, 173 long, struct tm*)), 174 long offset, int * okayp, int do_norm_secs)); 175 static void timesub P((const time_t * timep, long offset, 176 const struct state * sp, struct tm * tmp)); 177 static int tmcomp P((const struct tm * atmp, 178 const struct tm * btmp)); 179 static time_t transtime P((time_t janfirst, int year, 180 const struct rule * rulep, long offset)); 181 static int tzload P((const char * name, struct state * sp)); 182 static int tzparse P((const char * name, struct state * sp, 183 int lastditch)); 184 static void tzset_unlocked P((void)); 185 static void tzsetwall_unlocked P((void)); 186 #ifdef STD_INSPIRED 187 static long leapcorr P((time_t * timep)); 188 #endif 189 190 #ifdef ALL_STATE 191 static struct state * lclptr; 192 static struct state * gmtptr; 193 #endif /* defined ALL_STATE */ 194 195 #ifndef ALL_STATE 196 static struct state lclmem; 197 static struct state gmtmem; 198 #define lclptr (&lclmem) 199 #define gmtptr (&gmtmem) 200 #endif /* State Farm */ 201 202 #ifndef TZ_STRLEN_MAX 203 #define TZ_STRLEN_MAX 255 204 #endif /* !defined TZ_STRLEN_MAX */ 205 206 static char lcl_TZname[TZ_STRLEN_MAX + 1]; 207 static int lcl_is_set; 208 static int gmt_is_set; 209 210 __aconst char * tzname[2] = { 211 /* LINTED const castaway */ 212 (__aconst char *)wildabbr, 213 /* LINTED const castaway */ 214 (__aconst char *)wildabbr 215 }; 216 217 #ifdef _REENT 218 static rwlock_t lcl_lock = RWLOCK_INITIALIZER; 219 #endif 220 221 /* 222 ** Section 4.12.3 of X3.159-1989 requires that 223 ** Except for the strftime function, these functions [asctime, 224 ** ctime, gmtime, localtime] return values in one of two static 225 ** objects: a broken-down time structure and an array of char. 226 ** Thanks to Paul Eggert (eggert@twinsun.com) for noting this. 227 */ 228 229 static struct tm tm; 230 231 #ifdef USG_COMPAT 232 long int timezone = 0; 233 int daylight = 0; 234 #endif /* defined USG_COMPAT */ 235 236 #ifdef ALTZONE 237 time_t altzone = 0; 238 #endif /* defined ALTZONE */ 239 240 static long 241 detzcode(codep) 242 const char * const codep; 243 { 244 register long result; 245 246 /* 247 ** The first character must be sign extended on systems with >32bit 248 ** longs. This was solved differently in the master tzcode sources 249 ** (the fix first appeared in tzcode95c.tar.gz). But I believe 250 ** that this implementation is superior. 251 */ 252 253 #ifdef __STDC__ 254 #define SIGN_EXTEND_CHAR(x) ((signed char) x) 255 #else 256 #define SIGN_EXTEND_CHAR(x) ((x & 0x80) ? ((~0 << 8) | x) : x) 257 #endif 258 259 result = (SIGN_EXTEND_CHAR(codep[0]) << 24) \ 260 | (codep[1] & 0xff) << 16 \ 261 | (codep[2] & 0xff) << 8 262 | (codep[3] & 0xff); 263 return result; 264 } 265 266 static void 267 settzname P((void)) 268 { 269 register struct state * const sp = lclptr; 270 register int i; 271 272 /* LINTED const castaway */ 273 tzname[0] = (__aconst char *)wildabbr; 274 /* LINTED const castaway */ 275 tzname[1] = (__aconst char *)wildabbr; 276 #ifdef USG_COMPAT 277 daylight = 0; 278 timezone = 0; 279 #endif /* defined USG_COMPAT */ 280 #ifdef ALTZONE 281 altzone = 0; 282 #endif /* defined ALTZONE */ 283 #ifdef ALL_STATE 284 if (sp == NULL) { 285 tzname[0] = tzname[1] = (__aconst char *)gmt; 286 return; 287 } 288 #endif /* defined ALL_STATE */ 289 for (i = 0; i < sp->typecnt; ++i) { 290 register const struct ttinfo * const ttisp = &sp->ttis[i]; 291 292 tzname[ttisp->tt_isdst] = 293 &sp->chars[ttisp->tt_abbrind]; 294 #ifdef USG_COMPAT 295 if (ttisp->tt_isdst) 296 daylight = 1; 297 if (i == 0 || !ttisp->tt_isdst) 298 timezone = -(ttisp->tt_gmtoff); 299 #endif /* defined USG_COMPAT */ 300 #ifdef ALTZONE 301 if (i == 0 || ttisp->tt_isdst) 302 altzone = -(ttisp->tt_gmtoff); 303 #endif /* defined ALTZONE */ 304 } 305 /* 306 ** And to get the latest zone names into tzname. . . 307 */ 308 for (i = 0; i < sp->timecnt; ++i) { 309 register const struct ttinfo * const ttisp = 310 &sp->ttis[ 311 sp->types[i]]; 312 313 tzname[ttisp->tt_isdst] = 314 &sp->chars[ttisp->tt_abbrind]; 315 } 316 } 317 318 static int 319 tzload(name, sp) 320 register const char * name; 321 register struct state * const sp; 322 { 323 register const char * p; 324 register int i; 325 register int fid; 326 327 if (name == NULL && (name = TZDEFAULT) == NULL) 328 return -1; 329 330 { 331 register int doaccess; 332 /* 333 ** Section 4.9.1 of the C standard says that 334 ** "FILENAME_MAX expands to an integral constant expression 335 ** that is the size needed for an array of char large enough 336 ** to hold the longest file name string that the implementation 337 ** guarantees can be opened." 338 */ 339 char fullname[FILENAME_MAX + 1]; 340 341 if (name[0] == ':') 342 ++name; 343 doaccess = name[0] == '/'; 344 if (!doaccess) { 345 if ((p = TZDIR) == NULL) 346 return -1; 347 if ((strlen(p) + strlen(name) + 1) >= sizeof fullname) 348 return -1; 349 (void) strcpy(fullname, p); /* XXX strcpy is safe */ 350 (void) strcat(fullname, "/"); /* XXX strcat is safe */ 351 (void) strcat(fullname, name); /* XXX strcat is safe */ 352 /* 353 ** Set doaccess if '.' (as in "../") shows up in name. 354 */ 355 if (strchr(name, '.') != NULL) 356 doaccess = TRUE; 357 name = fullname; 358 } 359 if (doaccess && access(name, R_OK) != 0) 360 return -1; 361 /* 362 * XXX potential security problem here if user of a set-id 363 * program has set TZ (which is passed in as name) here, 364 * and uses a race condition trick to defeat the access(2) 365 * above. 366 */ 367 if ((fid = open(name, OPEN_MODE)) == -1) 368 return -1; 369 } 370 { 371 struct tzhead * tzhp; 372 union { 373 struct tzhead tzhead; 374 char buf[sizeof *sp + sizeof *tzhp]; 375 } u; 376 int ttisstdcnt; 377 int ttisgmtcnt; 378 379 i = read(fid, u.buf, sizeof u.buf); 380 if (close(fid) != 0) 381 return -1; 382 ttisstdcnt = (int) detzcode(u.tzhead.tzh_ttisgmtcnt); 383 ttisgmtcnt = (int) detzcode(u.tzhead.tzh_ttisstdcnt); 384 sp->leapcnt = (int) detzcode(u.tzhead.tzh_leapcnt); 385 sp->timecnt = (int) detzcode(u.tzhead.tzh_timecnt); 386 sp->typecnt = (int) detzcode(u.tzhead.tzh_typecnt); 387 sp->charcnt = (int) detzcode(u.tzhead.tzh_charcnt); 388 p = u.tzhead.tzh_charcnt + sizeof u.tzhead.tzh_charcnt; 389 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS || 390 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES || 391 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES || 392 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS || 393 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) || 394 (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0)) 395 return -1; 396 if (i - (p - u.buf) < sp->timecnt * 4 + /* ats */ 397 sp->timecnt + /* types */ 398 sp->typecnt * (4 + 2) + /* ttinfos */ 399 sp->charcnt + /* chars */ 400 sp->leapcnt * (4 + 4) + /* lsinfos */ 401 ttisstdcnt + /* ttisstds */ 402 ttisgmtcnt) /* ttisgmts */ 403 return -1; 404 for (i = 0; i < sp->timecnt; ++i) { 405 sp->ats[i] = detzcode(p); 406 p += 4; 407 } 408 for (i = 0; i < sp->timecnt; ++i) { 409 sp->types[i] = (unsigned char) *p++; 410 if (sp->types[i] >= sp->typecnt) 411 return -1; 412 } 413 for (i = 0; i < sp->typecnt; ++i) { 414 register struct ttinfo * ttisp; 415 416 ttisp = &sp->ttis[i]; 417 ttisp->tt_gmtoff = detzcode(p); 418 p += 4; 419 ttisp->tt_isdst = (unsigned char) *p++; 420 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1) 421 return -1; 422 ttisp->tt_abbrind = (unsigned char) *p++; 423 if (ttisp->tt_abbrind < 0 || 424 ttisp->tt_abbrind > sp->charcnt) 425 return -1; 426 } 427 for (i = 0; i < sp->charcnt; ++i) 428 sp->chars[i] = *p++; 429 sp->chars[i] = '\0'; /* ensure '\0' at end */ 430 for (i = 0; i < sp->leapcnt; ++i) { 431 register struct lsinfo * lsisp; 432 433 lsisp = &sp->lsis[i]; 434 lsisp->ls_trans = detzcode(p); 435 p += 4; 436 lsisp->ls_corr = detzcode(p); 437 p += 4; 438 } 439 for (i = 0; i < sp->typecnt; ++i) { 440 register struct ttinfo * ttisp; 441 442 ttisp = &sp->ttis[i]; 443 if (ttisstdcnt == 0) 444 ttisp->tt_ttisstd = FALSE; 445 else { 446 ttisp->tt_ttisstd = *p++; 447 if (ttisp->tt_ttisstd != TRUE && 448 ttisp->tt_ttisstd != FALSE) 449 return -1; 450 } 451 } 452 for (i = 0; i < sp->typecnt; ++i) { 453 register struct ttinfo * ttisp; 454 455 ttisp = &sp->ttis[i]; 456 if (ttisgmtcnt == 0) 457 ttisp->tt_ttisgmt = FALSE; 458 else { 459 ttisp->tt_ttisgmt = *p++; 460 if (ttisp->tt_ttisgmt != TRUE && 461 ttisp->tt_ttisgmt != FALSE) 462 return -1; 463 } 464 } 465 } 466 return 0; 467 } 468 469 static const int mon_lengths[2][MONSPERYEAR] = { 470 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, 471 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } 472 }; 473 474 static const int year_lengths[2] = { 475 DAYSPERNYEAR, DAYSPERLYEAR 476 }; 477 478 /* 479 ** Given a pointer into a time zone string, scan until a character that is not 480 ** a valid character in a zone name is found. Return a pointer to that 481 ** character. 482 */ 483 484 static const char * 485 getzname(strp) 486 register const char * strp; 487 { 488 register char c; 489 490 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && 491 c != '+') 492 ++strp; 493 return strp; 494 } 495 496 /* 497 ** Given a pointer into a time zone string, extract a number from that string. 498 ** Check that the number is within a specified range; if it is not, return 499 ** NULL. 500 ** Otherwise, return a pointer to the first character not part of the number. 501 */ 502 503 static const char * 504 getnum(strp, nump, min, max) 505 register const char * strp; 506 int * const nump; 507 const int min; 508 const int max; 509 { 510 register char c; 511 register int num; 512 513 if (strp == NULL || !is_digit(c = *strp)) 514 return NULL; 515 num = 0; 516 do { 517 num = num * 10 + (c - '0'); 518 if (num > max) 519 return NULL; /* illegal value */ 520 c = *++strp; 521 } while (is_digit(c)); 522 if (num < min) 523 return NULL; /* illegal value */ 524 *nump = num; 525 return strp; 526 } 527 528 /* 529 ** Given a pointer into a time zone string, extract a number of seconds, 530 ** in 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 number 533 ** of seconds. 534 */ 535 536 static const char * 537 getsecs(strp, secsp) 538 register const char * strp; 539 long * const secsp; 540 { 541 int num; 542 543 /* 544 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like 545 ** "M10.4.6/26", which does not conform to Posix, 546 ** but which specifies the equivalent of 547 ** ``02:00 on the first Sunday on or after 23 Oct''. 548 */ 549 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); 550 if (strp == NULL) 551 return NULL; 552 *secsp = num * (long) SECSPERHOUR; 553 if (*strp == ':') { 554 ++strp; 555 strp = getnum(strp, &num, 0, MINSPERHOUR - 1); 556 if (strp == NULL) 557 return NULL; 558 *secsp += num * SECSPERMIN; 559 if (*strp == ':') { 560 ++strp; 561 /* `SECSPERMIN' allows for leap seconds. */ 562 strp = getnum(strp, &num, 0, SECSPERMIN); 563 if (strp == NULL) 564 return NULL; 565 *secsp += num; 566 } 567 } 568 return strp; 569 } 570 571 /* 572 ** Given a pointer into a time zone string, extract an offset, in 573 ** [+-]hh[:mm[:ss]] form, from the string. 574 ** If any error occurs, return NULL. 575 ** Otherwise, return a pointer to the first character not part of the time. 576 */ 577 578 static const char * 579 getoffset(strp, offsetp) 580 register const char * strp; 581 long * const offsetp; 582 { 583 register int neg = 0; 584 585 if (*strp == '-') { 586 neg = 1; 587 ++strp; 588 } else if (*strp == '+') 589 ++strp; 590 strp = getsecs(strp, offsetp); 591 if (strp == NULL) 592 return NULL; /* illegal time */ 593 if (neg) 594 *offsetp = -*offsetp; 595 return strp; 596 } 597 598 /* 599 ** Given a pointer into a time zone string, extract a rule in the form 600 ** date[/time]. See POSIX section 8 for the format of "date" and "time". 601 ** If a valid rule is not found, return NULL. 602 ** Otherwise, return a pointer to the first character not part of the rule. 603 */ 604 605 static const char * 606 getrule(strp, rulep) 607 const char * strp; 608 register struct rule * const rulep; 609 { 610 if (*strp == 'J') { 611 /* 612 ** Julian day. 613 */ 614 rulep->r_type = JULIAN_DAY; 615 ++strp; 616 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); 617 } else if (*strp == 'M') { 618 /* 619 ** Month, week, day. 620 */ 621 rulep->r_type = MONTH_NTH_DAY_OF_WEEK; 622 ++strp; 623 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); 624 if (strp == NULL) 625 return NULL; 626 if (*strp++ != '.') 627 return NULL; 628 strp = getnum(strp, &rulep->r_week, 1, 5); 629 if (strp == NULL) 630 return NULL; 631 if (*strp++ != '.') 632 return NULL; 633 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); 634 } else if (is_digit(*strp)) { 635 /* 636 ** Day of year. 637 */ 638 rulep->r_type = DAY_OF_YEAR; 639 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); 640 } else return NULL; /* invalid format */ 641 if (strp == NULL) 642 return NULL; 643 if (*strp == '/') { 644 /* 645 ** Time specified. 646 */ 647 ++strp; 648 strp = getsecs(strp, &rulep->r_time); 649 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ 650 return strp; 651 } 652 653 /* 654 ** Given the Epoch-relative time of January 1, 00:00:00 UTC, in a year, the 655 ** year, a rule, and the offset from UTC at the time that rule takes effect, 656 ** calculate the Epoch-relative time that rule takes effect. 657 */ 658 659 static time_t 660 transtime(janfirst, year, rulep, offset) 661 const time_t janfirst; 662 const int year; 663 register const struct rule * const rulep; 664 const long offset; 665 { 666 register int leapyear; 667 register time_t value; 668 register int i; 669 int d, m1, yy0, yy1, yy2, dow; 670 671 INITIALIZE(value); 672 leapyear = isleap(year); 673 switch (rulep->r_type) { 674 675 case JULIAN_DAY: 676 /* 677 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap 678 ** years. 679 ** In non-leap years, or if the day number is 59 or less, just 680 ** add SECSPERDAY times the day number-1 to the time of 681 ** January 1, midnight, to get the day. 682 */ 683 value = janfirst + (rulep->r_day - 1) * SECSPERDAY; 684 if (leapyear && rulep->r_day >= 60) 685 value += SECSPERDAY; 686 break; 687 688 case DAY_OF_YEAR: 689 /* 690 ** n - day of year. 691 ** Just add SECSPERDAY times the day number to the time of 692 ** January 1, midnight, to get the day. 693 */ 694 value = janfirst + rulep->r_day * SECSPERDAY; 695 break; 696 697 case MONTH_NTH_DAY_OF_WEEK: 698 /* 699 ** Mm.n.d - nth "dth day" of month m. 700 */ 701 value = janfirst; 702 for (i = 0; i < rulep->r_mon - 1; ++i) 703 value += mon_lengths[leapyear][i] * SECSPERDAY; 704 705 /* 706 ** Use Zeller's Congruence to get day-of-week of first day of 707 ** month. 708 */ 709 m1 = (rulep->r_mon + 9) % 12 + 1; 710 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; 711 yy1 = yy0 / 100; 712 yy2 = yy0 % 100; 713 dow = ((26 * m1 - 2) / 10 + 714 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; 715 if (dow < 0) 716 dow += DAYSPERWEEK; 717 718 /* 719 ** "dow" is the day-of-week of the first day of the month. Get 720 ** the day-of-month (zero-origin) of the first "dow" day of the 721 ** month. 722 */ 723 d = rulep->r_day - dow; 724 if (d < 0) 725 d += DAYSPERWEEK; 726 for (i = 1; i < rulep->r_week; ++i) { 727 if (d + DAYSPERWEEK >= 728 mon_lengths[leapyear][rulep->r_mon - 1]) 729 break; 730 d += DAYSPERWEEK; 731 } 732 733 /* 734 ** "d" is the day-of-month (zero-origin) of the day we want. 735 */ 736 value += d * SECSPERDAY; 737 break; 738 } 739 740 /* 741 ** "value" is the Epoch-relative time of 00:00:00 UTC on the day in 742 ** question. To get the Epoch-relative time of the specified local 743 ** time on that day, add the transition time and the current offset 744 ** from UTC. 745 */ 746 return value + rulep->r_time + offset; 747 } 748 749 /* 750 ** Given a POSIX section 8-style TZ string, fill in the rule tables as 751 ** appropriate. 752 */ 753 754 static int 755 tzparse(name, sp, lastditch) 756 const char * name; 757 register struct state * const sp; 758 const int lastditch; 759 { 760 const char * stdname; 761 const char * dstname; 762 size_t stdlen; 763 size_t dstlen; 764 long stdoffset; 765 long dstoffset; 766 register time_t * atp; 767 register unsigned char * typep; 768 register char * cp; 769 register int load_result; 770 771 INITIALIZE(dstname); 772 stdname = name; 773 if (lastditch) { 774 stdlen = strlen(name); /* length of standard zone name */ 775 name += stdlen; 776 if (stdlen >= sizeof sp->chars) 777 stdlen = (sizeof sp->chars) - 1; 778 stdoffset = 0; 779 } else { 780 name = getzname(name); 781 stdlen = name - stdname; 782 if (stdlen < 3) 783 return -1; 784 if (*name == '\0') 785 return -1; 786 name = getoffset(name, &stdoffset); 787 if (name == NULL) 788 return -1; 789 } 790 load_result = tzload(TZDEFRULES, sp); 791 if (load_result != 0) 792 sp->leapcnt = 0; /* so, we're off a little */ 793 if (*name != '\0') { 794 dstname = name; 795 name = getzname(name); 796 dstlen = name - dstname; /* length of DST zone name */ 797 if (dstlen < 3) 798 return -1; 799 if (*name != '\0' && *name != ',' && *name != ';') { 800 name = getoffset(name, &dstoffset); 801 if (name == NULL) 802 return -1; 803 } else dstoffset = stdoffset - SECSPERHOUR; 804 if (*name == '\0' && load_result != 0) 805 name = TZDEFRULESTRING; 806 if (*name == ',' || *name == ';') { 807 struct rule start; 808 struct rule end; 809 register int year; 810 register time_t janfirst; 811 time_t starttime; 812 time_t endtime; 813 814 ++name; 815 if ((name = getrule(name, &start)) == NULL) 816 return -1; 817 if (*name++ != ',') 818 return -1; 819 if ((name = getrule(name, &end)) == NULL) 820 return -1; 821 if (*name != '\0') 822 return -1; 823 sp->typecnt = 2; /* standard time and DST */ 824 /* 825 ** Two transitions per year, from EPOCH_YEAR to 2037. 826 */ 827 sp->timecnt = 2 * (2037 - EPOCH_YEAR + 1); 828 if (sp->timecnt > TZ_MAX_TIMES) 829 return -1; 830 sp->ttis[0].tt_gmtoff = -dstoffset; 831 sp->ttis[0].tt_isdst = 1; 832 sp->ttis[0].tt_abbrind = stdlen + 1; 833 sp->ttis[1].tt_gmtoff = -stdoffset; 834 sp->ttis[1].tt_isdst = 0; 835 sp->ttis[1].tt_abbrind = 0; 836 atp = sp->ats; 837 typep = sp->types; 838 janfirst = 0; 839 for (year = EPOCH_YEAR; year <= 2037; ++year) { 840 starttime = transtime(janfirst, year, &start, 841 stdoffset); 842 endtime = transtime(janfirst, year, &end, 843 dstoffset); 844 if (starttime > endtime) { 845 *atp++ = endtime; 846 *typep++ = 1; /* DST ends */ 847 *atp++ = starttime; 848 *typep++ = 0; /* DST begins */ 849 } else { 850 *atp++ = starttime; 851 *typep++ = 0; /* DST begins */ 852 *atp++ = endtime; 853 *typep++ = 1; /* DST ends */ 854 } 855 janfirst += year_lengths[isleap(year)] * 856 SECSPERDAY; 857 } 858 } else { 859 register long theirstdoffset; 860 register long theirdstoffset; 861 register long theiroffset; 862 register int isdst; 863 register int i; 864 register int j; 865 866 if (*name != '\0') 867 return -1; 868 /* 869 ** Initial values of theirstdoffset and theirdstoffset. 870 */ 871 theirstdoffset = 0; 872 for (i = 0; i < sp->timecnt; ++i) { 873 j = sp->types[i]; 874 if (!sp->ttis[j].tt_isdst) { 875 theirstdoffset = 876 -sp->ttis[j].tt_gmtoff; 877 break; 878 } 879 } 880 theirdstoffset = 0; 881 for (i = 0; i < sp->timecnt; ++i) { 882 j = sp->types[i]; 883 if (sp->ttis[j].tt_isdst) { 884 theirdstoffset = 885 -sp->ttis[j].tt_gmtoff; 886 break; 887 } 888 } 889 /* 890 ** Initially we're assumed to be in standard time. 891 */ 892 isdst = FALSE; 893 theiroffset = theirstdoffset; 894 /* 895 ** Now juggle transition times and types 896 ** tracking offsets as you do. 897 */ 898 for (i = 0; i < sp->timecnt; ++i) { 899 j = sp->types[i]; 900 sp->types[i] = sp->ttis[j].tt_isdst; 901 if (sp->ttis[j].tt_ttisgmt) { 902 /* No adjustment to transition time */ 903 } else { 904 /* 905 ** If summer time is in effect, and the 906 ** transition time was not specified as 907 ** standard time, add the summer time 908 ** offset to the transition time; 909 ** otherwise, add the standard time 910 ** offset to the transition time. 911 */ 912 /* 913 ** Transitions from DST to DDST 914 ** will effectively disappear since 915 ** POSIX provides for only one DST 916 ** offset. 917 */ 918 if (isdst && !sp->ttis[j].tt_ttisstd) { 919 sp->ats[i] += dstoffset - 920 theirdstoffset; 921 } else { 922 sp->ats[i] += stdoffset - 923 theirstdoffset; 924 } 925 } 926 theiroffset = -sp->ttis[j].tt_gmtoff; 927 if (sp->ttis[j].tt_isdst) 928 theirdstoffset = theiroffset; 929 else theirstdoffset = theiroffset; 930 } 931 /* 932 ** Finally, fill in ttis. 933 ** ttisstd and ttisgmt need not be handled. 934 */ 935 sp->ttis[0].tt_gmtoff = -stdoffset; 936 sp->ttis[0].tt_isdst = FALSE; 937 sp->ttis[0].tt_abbrind = 0; 938 sp->ttis[1].tt_gmtoff = -dstoffset; 939 sp->ttis[1].tt_isdst = TRUE; 940 sp->ttis[1].tt_abbrind = stdlen + 1; 941 sp->typecnt = 2; 942 } 943 } else { 944 dstlen = 0; 945 sp->typecnt = 1; /* only standard time */ 946 sp->timecnt = 0; 947 sp->ttis[0].tt_gmtoff = -stdoffset; 948 sp->ttis[0].tt_isdst = 0; 949 sp->ttis[0].tt_abbrind = 0; 950 } 951 sp->charcnt = stdlen + 1; 952 if (dstlen != 0) 953 sp->charcnt += dstlen + 1; 954 if ((size_t) sp->charcnt > sizeof sp->chars) 955 return -1; 956 cp = sp->chars; 957 (void) strncpy(cp, stdname, stdlen); 958 cp += stdlen; 959 *cp++ = '\0'; 960 if (dstlen != 0) { 961 (void) strncpy(cp, dstname, dstlen); 962 *(cp + dstlen) = '\0'; 963 } 964 return 0; 965 } 966 967 static void 968 gmtload(sp) 969 struct state * const sp; 970 { 971 if (tzload(gmt, sp) != 0) 972 (void) tzparse(gmt, sp, TRUE); 973 } 974 975 static void 976 tzsetwall_unlocked P((void)) 977 { 978 if (lcl_is_set < 0) 979 return; 980 lcl_is_set = -1; 981 982 #ifdef ALL_STATE 983 if (lclptr == NULL) { 984 lclptr = (struct state *) malloc(sizeof *lclptr); 985 if (lclptr == NULL) { 986 settzname(); /* all we can do */ 987 return; 988 } 989 } 990 #endif /* defined ALL_STATE */ 991 if (tzload((char *) NULL, lclptr) != 0) 992 gmtload(lclptr); 993 settzname(); 994 } 995 996 #ifndef STD_INSPIRED 997 /* 998 ** A non-static declaration of tzsetwall in a system header file 999 ** may cause a warning about this upcoming static declaration... 1000 */ 1001 static 1002 #endif /* !defined STD_INSPIRED */ 1003 void 1004 tzsetwall P((void)) 1005 { 1006 rwlock_wrlock(&lcl_lock); 1007 tzsetwall_unlocked(); 1008 rwlock_unlock(&lcl_lock); 1009 } 1010 1011 static void 1012 tzset_unlocked P((void)) 1013 { 1014 register const char * name; 1015 1016 name = getenv("TZ"); 1017 if (name == NULL) { 1018 tzsetwall_unlocked(); 1019 return; 1020 } 1021 1022 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) 1023 return; 1024 lcl_is_set = (strlen(name) < sizeof(lcl_TZname)); 1025 if (lcl_is_set) 1026 (void)strncpy(lcl_TZname, name, sizeof(lcl_TZname) - 1); 1027 1028 #ifdef ALL_STATE 1029 if (lclptr == NULL) { 1030 lclptr = (struct state *) malloc(sizeof *lclptr); 1031 if (lclptr == NULL) { 1032 settzname(); /* all we can do */ 1033 return; 1034 } 1035 } 1036 #endif /* defined ALL_STATE */ 1037 if (*name == '\0') { 1038 /* 1039 ** User wants it fast rather than right. 1040 */ 1041 lclptr->leapcnt = 0; /* so, we're off a little */ 1042 lclptr->timecnt = 0; 1043 lclptr->typecnt = 0; 1044 lclptr->ttis[0].tt_isdst = 0; 1045 lclptr->ttis[0].tt_gmtoff = 0; 1046 lclptr->ttis[0].tt_abbrind = 0; 1047 (void)strncpy(lclptr->chars, gmt, sizeof(lclptr->chars) - 1); 1048 } else if (tzload(name, lclptr) != 0) 1049 if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0) 1050 (void) gmtload(lclptr); 1051 settzname(); 1052 } 1053 1054 void 1055 tzset P((void)) 1056 { 1057 rwlock_wrlock(&lcl_lock); 1058 tzset_unlocked(); 1059 rwlock_unlock(&lcl_lock); 1060 } 1061 1062 /* 1063 ** The easy way to behave "as if no library function calls" localtime 1064 ** is to not call it--so we drop its guts into "localsub", which can be 1065 ** freely called. (And no, the PANS doesn't require the above behavior-- 1066 ** but it *is* desirable.) 1067 ** 1068 ** The unused offset argument is for the benefit of mktime variants. 1069 */ 1070 1071 /*ARGSUSED*/ 1072 static void 1073 localsub(timep, offset, tmp) 1074 const time_t * const timep; 1075 const long offset; 1076 struct tm * const tmp; 1077 { 1078 register struct state * sp; 1079 register const struct ttinfo * ttisp; 1080 register int i; 1081 const time_t t = *timep; 1082 1083 sp = lclptr; 1084 #ifdef ALL_STATE 1085 if (sp == NULL) { 1086 gmtsub(timep, offset, tmp); 1087 return; 1088 } 1089 #endif /* defined ALL_STATE */ 1090 if (sp->timecnt == 0 || t < sp->ats[0]) { 1091 i = 0; 1092 while (sp->ttis[i].tt_isdst) 1093 if (++i >= sp->typecnt) { 1094 i = 0; 1095 break; 1096 } 1097 } else { 1098 for (i = 1; i < sp->timecnt; ++i) 1099 if (t < sp->ats[i]) 1100 break; 1101 i = sp->types[i - 1]; 1102 } 1103 ttisp = &sp->ttis[i]; 1104 /* 1105 ** To get (wrong) behavior that's compatible with System V Release 2.0 1106 ** you'd replace the statement below with 1107 ** t += ttisp->tt_gmtoff; 1108 ** timesub(&t, 0L, sp, tmp); 1109 */ 1110 timesub(&t, ttisp->tt_gmtoff, sp, tmp); 1111 tmp->tm_isdst = ttisp->tt_isdst; 1112 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind]; 1113 #ifdef TM_ZONE 1114 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind]; 1115 #endif /* defined TM_ZONE */ 1116 } 1117 1118 struct tm * 1119 localtime(timep) 1120 const time_t * const timep; 1121 { 1122 rwlock_wrlock(&lcl_lock); 1123 tzset_unlocked(); 1124 localsub(timep, 0L, &tm); 1125 rwlock_unlock(&lcl_lock); 1126 return &tm; 1127 } 1128 1129 /* 1130 * Re-entrant version of localtime 1131 */ 1132 struct tm * 1133 localtime_r(timep, tmp) 1134 const time_t * const timep; 1135 struct tm * tmp; 1136 { 1137 rwlock_rdlock(&lcl_lock); 1138 localsub(timep, 0L, tmp); 1139 rwlock_unlock(&lcl_lock); 1140 return tmp; 1141 } 1142 1143 /* 1144 ** gmtsub is to gmtime as localsub is to localtime. 1145 */ 1146 1147 static void 1148 gmtsub(timep, offset, tmp) 1149 const time_t * const timep; 1150 const long offset; 1151 struct tm * const tmp; 1152 { 1153 #ifdef _REENT 1154 static mutex_t gmt_mutex = MUTEX_INITIALIZER; 1155 #endif 1156 1157 mutex_lock(&gmt_mutex); 1158 if (!gmt_is_set) { 1159 gmt_is_set = TRUE; 1160 #ifdef ALL_STATE 1161 gmtptr = (struct state *) malloc(sizeof *gmtptr); 1162 if (gmtptr != NULL) 1163 #endif /* defined ALL_STATE */ 1164 gmtload(gmtptr); 1165 } 1166 mutex_unlock(&gmt_mutex); 1167 timesub(timep, offset, gmtptr, tmp); 1168 #ifdef TM_ZONE 1169 /* 1170 ** Could get fancy here and deliver something such as 1171 ** "UTC+xxxx" or "UTC-xxxx" if offset is non-zero, 1172 ** but this is no time for a treasure hunt. 1173 */ 1174 if (offset != 0) 1175 /* LINTED const castaway */ 1176 tmp->TM_ZONE = (__aconst char *)wildabbr; 1177 else { 1178 #ifdef ALL_STATE 1179 if (gmtptr == NULL) 1180 tmp->TM_ZONE = (__aconst char *)gmt; 1181 else tmp->TM_ZONE = gmtptr->chars; 1182 #endif /* defined ALL_STATE */ 1183 #ifndef ALL_STATE 1184 tmp->TM_ZONE = gmtptr->chars; 1185 #endif /* State Farm */ 1186 } 1187 #endif /* defined TM_ZONE */ 1188 } 1189 1190 struct tm * 1191 gmtime(timep) 1192 const time_t * const timep; 1193 { 1194 gmtsub(timep, 0L, &tm); 1195 return &tm; 1196 } 1197 1198 /* 1199 * Re-entrant version of gmtime 1200 */ 1201 struct tm * 1202 gmtime_r(timep, tmp) 1203 const time_t * const timep; 1204 struct tm * tmp; 1205 { 1206 gmtsub(timep, 0L, tmp); 1207 return tmp; 1208 } 1209 1210 #ifdef STD_INSPIRED 1211 1212 struct tm * 1213 offtime(timep, offset) 1214 const time_t * const timep; 1215 const long offset; 1216 { 1217 gmtsub(timep, offset, &tm); 1218 return &tm; 1219 } 1220 1221 #endif /* defined STD_INSPIRED */ 1222 1223 static void 1224 timesub(timep, offset, sp, tmp) 1225 const time_t * const timep; 1226 const long offset; 1227 register const struct state * const sp; 1228 register struct tm * const tmp; 1229 { 1230 register const struct lsinfo * lp; 1231 register long days; 1232 register long rem; 1233 register int y; 1234 register int yleap; 1235 register const int * ip; 1236 register long corr; 1237 register int hit; 1238 register int i; 1239 1240 corr = 0; 1241 hit = 0; 1242 #ifdef ALL_STATE 1243 i = (sp == NULL) ? 0 : sp->leapcnt; 1244 #endif /* defined ALL_STATE */ 1245 #ifndef ALL_STATE 1246 i = sp->leapcnt; 1247 #endif /* State Farm */ 1248 while (--i >= 0) { 1249 lp = &sp->lsis[i]; 1250 if (*timep >= lp->ls_trans) { 1251 if (*timep == lp->ls_trans) { 1252 hit = ((i == 0 && lp->ls_corr > 0) || 1253 lp->ls_corr > sp->lsis[i - 1].ls_corr); 1254 if (hit) 1255 while (i > 0 && 1256 sp->lsis[i].ls_trans == 1257 sp->lsis[i - 1].ls_trans + 1 && 1258 sp->lsis[i].ls_corr == 1259 sp->lsis[i - 1].ls_corr + 1) { 1260 ++hit; 1261 --i; 1262 } 1263 } 1264 corr = lp->ls_corr; 1265 break; 1266 } 1267 } 1268 days = *timep / SECSPERDAY; 1269 rem = *timep % SECSPERDAY; 1270 #ifdef mc68k 1271 if (*timep == 0x80000000) { 1272 /* 1273 ** A 3B1 muffs the division on the most negative number. 1274 */ 1275 days = -24855; 1276 rem = -11648; 1277 } 1278 #endif /* defined mc68k */ 1279 rem += (offset - corr); 1280 while (rem < 0) { 1281 rem += SECSPERDAY; 1282 --days; 1283 } 1284 while (rem >= SECSPERDAY) { 1285 rem -= SECSPERDAY; 1286 ++days; 1287 } 1288 tmp->tm_hour = (int) (rem / SECSPERHOUR); 1289 rem = rem % SECSPERHOUR; 1290 tmp->tm_min = (int) (rem / SECSPERMIN); 1291 /* 1292 ** A positive leap second requires a special 1293 ** representation. This uses "... ??:59:60" et seq. 1294 */ 1295 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit; 1296 tmp->tm_wday = (int) ((EPOCH_WDAY + days) % DAYSPERWEEK); 1297 if (tmp->tm_wday < 0) 1298 tmp->tm_wday += DAYSPERWEEK; 1299 y = EPOCH_YEAR; 1300 #define LEAPS_THRU_END_OF(y) ((y) / 4 - (y) / 100 + (y) / 400) 1301 while (days < 0 || days >= (long) year_lengths[yleap = isleap(y)]) { 1302 register int newy; 1303 1304 newy = (int)(y + days / DAYSPERNYEAR); 1305 if (days < 0) 1306 --newy; 1307 days -= (newy - y) * DAYSPERNYEAR + 1308 LEAPS_THRU_END_OF(newy - 1) - 1309 LEAPS_THRU_END_OF(y - 1); 1310 y = newy; 1311 } 1312 tmp->tm_year = y - TM_YEAR_BASE; 1313 tmp->tm_yday = (int) days; 1314 ip = mon_lengths[yleap]; 1315 for (tmp->tm_mon = 0; days >= (long) ip[tmp->tm_mon]; ++(tmp->tm_mon)) 1316 days = days - (long) ip[tmp->tm_mon]; 1317 tmp->tm_mday = (int) (days + 1); 1318 tmp->tm_isdst = 0; 1319 #ifdef TM_GMTOFF 1320 tmp->TM_GMTOFF = offset; 1321 #endif /* defined TM_GMTOFF */ 1322 } 1323 1324 char * 1325 ctime(timep) 1326 const time_t * const timep; 1327 { 1328 /* 1329 ** Section 4.12.3.2 of X3.159-1989 requires that 1330 ** The ctime function converts the calendar time pointed to by timer 1331 ** to local time in the form of a string. It is equivalent to 1332 ** asctime(localtime(timer)) 1333 */ 1334 return asctime(localtime(timep)); 1335 } 1336 1337 char * 1338 ctime_r(timep, buf) 1339 const time_t * const timep; 1340 char * buf; 1341 { 1342 struct tm tmp; 1343 1344 return asctime_r(localtime_r(timep, &tmp), buf); 1345 } 1346 1347 /* 1348 ** Adapted from code provided by Robert Elz, who writes: 1349 ** The "best" way to do mktime I think is based on an idea of Bob 1350 ** Kridle's (so its said...) from a long time ago. 1351 ** [kridle@xinet.com as of 1996-01-16.] 1352 ** It does a binary search of the time_t space. Since time_t's are 1353 ** just 32 bits, its a max of 32 iterations (even at 64 bits it 1354 ** would still be very reasonable). 1355 */ 1356 1357 #ifndef WRONG 1358 #define WRONG (-1) 1359 #endif /* !defined WRONG */ 1360 1361 /* 1362 ** Simplified normalize logic courtesy Paul Eggert (eggert@twinsun.com). 1363 */ 1364 1365 static int 1366 increment_overflow(number, delta) 1367 int * number; 1368 int delta; 1369 { 1370 int number0; 1371 1372 number0 = *number; 1373 *number += delta; 1374 return (*number < number0) != (delta < 0); 1375 } 1376 1377 static int 1378 normalize_overflow(tensptr, unitsptr, base) 1379 int * const tensptr; 1380 int * const unitsptr; 1381 const int base; 1382 { 1383 register int tensdelta; 1384 1385 tensdelta = (*unitsptr >= 0) ? 1386 (*unitsptr / base) : 1387 (-1 - (-1 - *unitsptr) / base); 1388 *unitsptr -= tensdelta * base; 1389 return increment_overflow(tensptr, tensdelta); 1390 } 1391 1392 static int 1393 tmcomp(atmp, btmp) 1394 register const struct tm * const atmp; 1395 register const struct tm * const btmp; 1396 { 1397 register int result; 1398 1399 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 && 1400 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 && 1401 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && 1402 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && 1403 (result = (atmp->tm_min - btmp->tm_min)) == 0) 1404 result = atmp->tm_sec - btmp->tm_sec; 1405 return result; 1406 } 1407 1408 static time_t 1409 time2sub(tmp, funcp, offset, okayp, do_norm_secs) 1410 struct tm * const tmp; 1411 void (* const funcp) P((const time_t*, long, struct tm*)); 1412 const long offset; 1413 int * const okayp; 1414 const int do_norm_secs; 1415 { 1416 register const struct state * sp; 1417 register int dir; 1418 register int bits; 1419 register int i, j ; 1420 register int saved_seconds; 1421 time_t newt; 1422 time_t t; 1423 struct tm yourtm, mytm; 1424 1425 *okayp = FALSE; 1426 yourtm = *tmp; 1427 if (do_norm_secs) { 1428 if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec, 1429 SECSPERMIN)) 1430 return WRONG; 1431 } 1432 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) 1433 return WRONG; 1434 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) 1435 return WRONG; 1436 if (normalize_overflow(&yourtm.tm_year, &yourtm.tm_mon, MONSPERYEAR)) 1437 return WRONG; 1438 /* 1439 ** Turn yourtm.tm_year into an actual year number for now. 1440 ** It is converted back to an offset from TM_YEAR_BASE later. 1441 */ 1442 if (increment_overflow(&yourtm.tm_year, TM_YEAR_BASE)) 1443 return WRONG; 1444 while (yourtm.tm_mday <= 0) { 1445 if (increment_overflow(&yourtm.tm_year, -1)) 1446 return WRONG; 1447 i = yourtm.tm_year + (1 < yourtm.tm_mon); 1448 yourtm.tm_mday += year_lengths[isleap(i)]; 1449 } 1450 while (yourtm.tm_mday > DAYSPERLYEAR) { 1451 i = yourtm.tm_year + (1 < yourtm.tm_mon); 1452 yourtm.tm_mday -= year_lengths[isleap(i)]; 1453 if (increment_overflow(&yourtm.tm_year, 1)) 1454 return WRONG; 1455 } 1456 for ( ; ; ) { 1457 i = mon_lengths[isleap(yourtm.tm_year)][yourtm.tm_mon]; 1458 if (yourtm.tm_mday <= i) 1459 break; 1460 yourtm.tm_mday -= i; 1461 if (++yourtm.tm_mon >= MONSPERYEAR) { 1462 yourtm.tm_mon = 0; 1463 if (increment_overflow(&yourtm.tm_year, 1)) 1464 return WRONG; 1465 } 1466 } 1467 if (increment_overflow(&yourtm.tm_year, -TM_YEAR_BASE)) 1468 return WRONG; 1469 if (yourtm.tm_year + TM_YEAR_BASE < EPOCH_YEAR) { 1470 /* 1471 ** We can't set tm_sec to 0, because that might push the 1472 ** time below the minimum representable time. 1473 ** Set tm_sec to 59 instead. 1474 ** This assumes that the minimum representable time is 1475 ** not in the same minute that a leap second was deleted from, 1476 ** which is a safer assumption than using 58 would be. 1477 */ 1478 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) 1479 return WRONG; 1480 saved_seconds = yourtm.tm_sec; 1481 yourtm.tm_sec = SECSPERMIN - 1; 1482 } else { 1483 saved_seconds = yourtm.tm_sec; 1484 yourtm.tm_sec = 0; 1485 } 1486 /* 1487 ** Divide the search space in half 1488 ** (this works whether time_t is signed or unsigned). 1489 */ 1490 bits = TYPE_BIT(time_t) - 1; 1491 /* 1492 ** If time_t is signed, then 0 is just above the median, 1493 ** assuming two's complement arithmetic. 1494 ** If time_t is unsigned, then (1 << bits) is just above the median. 1495 */ 1496 /* LINTED constant in conditional context */ 1497 t = TYPE_SIGNED(time_t) ? 0 : (((time_t) 1) << bits); 1498 for ( ; ; ) { 1499 (*funcp)(&t, offset, &mytm); 1500 dir = tmcomp(&mytm, &yourtm); 1501 if (dir != 0) { 1502 if (bits-- < 0) 1503 return WRONG; 1504 if (bits < 0) 1505 --t; /* may be needed if new t is minimal */ 1506 else if (dir > 0) 1507 t -= ((time_t) 1) << bits; 1508 else t += ((time_t) 1) << bits; 1509 continue; 1510 } 1511 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) 1512 break; 1513 /* 1514 ** Right time, wrong type. 1515 ** Hunt for right time, right type. 1516 ** It's okay to guess wrong since the guess 1517 ** gets checked. 1518 */ 1519 /* 1520 ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's. 1521 */ 1522 sp = (const struct state *) 1523 (((void *) funcp == (void *) localsub) ? 1524 lclptr : gmtptr); 1525 #ifdef ALL_STATE 1526 if (sp == NULL) 1527 return WRONG; 1528 #endif /* defined ALL_STATE */ 1529 for (i = sp->typecnt - 1; i >= 0; --i) { 1530 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) 1531 continue; 1532 for (j = sp->typecnt - 1; j >= 0; --j) { 1533 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) 1534 continue; 1535 newt = t + sp->ttis[j].tt_gmtoff - 1536 sp->ttis[i].tt_gmtoff; 1537 (*funcp)(&newt, offset, &mytm); 1538 if (tmcomp(&mytm, &yourtm) != 0) 1539 continue; 1540 if (mytm.tm_isdst != yourtm.tm_isdst) 1541 continue; 1542 /* 1543 ** We have a match. 1544 */ 1545 t = newt; 1546 goto label; 1547 } 1548 } 1549 return WRONG; 1550 } 1551 label: 1552 newt = t + saved_seconds; 1553 if ((newt < t) != (saved_seconds < 0)) 1554 return WRONG; 1555 t = newt; 1556 (*funcp)(&t, offset, tmp); 1557 *okayp = TRUE; 1558 return t; 1559 } 1560 1561 static time_t 1562 time2(tmp, funcp, offset, okayp) 1563 struct tm * const tmp; 1564 void (* const funcp) P((const time_t*, long, struct tm*)); 1565 const long offset; 1566 int * const okayp; 1567 { 1568 time_t t; 1569 1570 /* 1571 ** First try without normalization of seconds 1572 ** (in case tm_sec contains a value associated with a leap second). 1573 ** If that fails, try with normalization of seconds. 1574 */ 1575 t = time2sub(tmp, funcp, offset, okayp, FALSE); 1576 return *okayp ? t : time2sub(tmp, funcp, offset, okayp, TRUE); 1577 } 1578 1579 static time_t 1580 time1(tmp, funcp, offset) 1581 struct tm * const tmp; 1582 void (* const funcp) P((const time_t *, long, struct tm *)); 1583 const long offset; 1584 { 1585 register time_t t; 1586 register const struct state * sp; 1587 register int samei, otheri; 1588 int okay; 1589 1590 if (tmp->tm_isdst > 1) 1591 tmp->tm_isdst = 1; 1592 t = time2(tmp, funcp, offset, &okay); 1593 #ifdef PCTS 1594 /* 1595 ** PCTS code courtesy Grant Sullivan (grant@osf.org). 1596 */ 1597 if (okay) 1598 return t; 1599 if (tmp->tm_isdst < 0) 1600 tmp->tm_isdst = 0; /* reset to std and try again */ 1601 #endif /* defined PCTS */ 1602 #ifndef PCTS 1603 if (okay || tmp->tm_isdst < 0) 1604 return t; 1605 #endif /* !defined PCTS */ 1606 /* 1607 ** We're supposed to assume that somebody took a time of one type 1608 ** and did some math on it that yielded a "struct tm" that's bad. 1609 ** We try to divine the type they started from and adjust to the 1610 ** type they need. 1611 */ 1612 /* 1613 ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's. 1614 */ 1615 sp = (const struct state *) (((void *) funcp == (void *) localsub) ? 1616 lclptr : gmtptr); 1617 #ifdef ALL_STATE 1618 if (sp == NULL) 1619 return WRONG; 1620 #endif /* defined ALL_STATE */ 1621 for (samei = sp->typecnt - 1; samei >= 0; --samei) { 1622 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) 1623 continue; 1624 for (otheri = sp->typecnt - 1; otheri >= 0; --otheri) { 1625 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) 1626 continue; 1627 tmp->tm_sec += (int)(sp->ttis[otheri].tt_gmtoff - 1628 sp->ttis[samei].tt_gmtoff); 1629 tmp->tm_isdst = !tmp->tm_isdst; 1630 t = time2(tmp, funcp, offset, &okay); 1631 if (okay) 1632 return t; 1633 tmp->tm_sec -= (int)(sp->ttis[otheri].tt_gmtoff - 1634 sp->ttis[samei].tt_gmtoff); 1635 tmp->tm_isdst = !tmp->tm_isdst; 1636 } 1637 } 1638 return WRONG; 1639 } 1640 1641 time_t 1642 mktime(tmp) 1643 struct tm * const tmp; 1644 { 1645 time_t result; 1646 1647 rwlock_wrlock(&lcl_lock); 1648 tzset_unlocked(); 1649 result = time1(tmp, localsub, 0L); 1650 rwlock_unlock(&lcl_lock); 1651 return (result); 1652 } 1653 1654 #ifdef STD_INSPIRED 1655 1656 time_t 1657 timelocal(tmp) 1658 struct tm * const tmp; 1659 { 1660 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 1661 return mktime(tmp); 1662 } 1663 1664 time_t 1665 timegm(tmp) 1666 struct tm * const tmp; 1667 { 1668 tmp->tm_isdst = 0; 1669 return time1(tmp, gmtsub, 0L); 1670 } 1671 1672 time_t 1673 timeoff(tmp, offset) 1674 struct tm * const tmp; 1675 const long offset; 1676 { 1677 tmp->tm_isdst = 0; 1678 return time1(tmp, gmtsub, offset); 1679 } 1680 1681 #endif /* defined STD_INSPIRED */ 1682 1683 #ifdef CMUCS 1684 1685 /* 1686 ** The following is supplied for compatibility with 1687 ** previous versions of the CMUCS runtime library. 1688 */ 1689 1690 long 1691 gtime(tmp) 1692 struct tm * const tmp; 1693 { 1694 const time_t t = mktime(tmp); 1695 1696 if (t == WRONG) 1697 return -1; 1698 return t; 1699 } 1700 1701 #endif /* defined CMUCS */ 1702 1703 /* 1704 ** XXX--is the below the right way to conditionalize?? 1705 */ 1706 1707 #ifdef STD_INSPIRED 1708 1709 /* 1710 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 1711 ** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which 1712 ** is not the case if we are accounting for leap seconds. 1713 ** So, we provide the following conversion routines for use 1714 ** when exchanging timestamps with POSIX conforming systems. 1715 */ 1716 1717 static long 1718 leapcorr(timep) 1719 time_t * timep; 1720 { 1721 register struct state * sp; 1722 register struct lsinfo * lp; 1723 register int i; 1724 1725 sp = lclptr; 1726 i = sp->leapcnt; 1727 while (--i >= 0) { 1728 lp = &sp->lsis[i]; 1729 if (*timep >= lp->ls_trans) 1730 return lp->ls_corr; 1731 } 1732 return 0; 1733 } 1734 1735 time_t 1736 time2posix(t) 1737 time_t t; 1738 { 1739 time_t result; 1740 1741 rwlock_wrlock(&lcl_lock); 1742 tzset_unlocked(); 1743 result = t - leapcorr(&t); 1744 rwlock_unlock(&lcl_lock); 1745 return (result); 1746 } 1747 1748 time_t 1749 posix2time(t) 1750 time_t t; 1751 { 1752 time_t x; 1753 time_t y; 1754 1755 rwlock_wrlock(&lcl_lock); 1756 tzset_unlocked(); 1757 /* 1758 ** For a positive leap second hit, the result 1759 ** is not unique. For a negative leap second 1760 ** hit, the corresponding time doesn't exist, 1761 ** so we return an adjacent second. 1762 */ 1763 x = t + leapcorr(&t); 1764 y = x - leapcorr(&x); 1765 if (y < t) { 1766 do { 1767 x++; 1768 y = x - leapcorr(&x); 1769 } while (y < t); 1770 if (t != y) { 1771 rwlock_unlock(&lcl_lock); 1772 return x - 1; 1773 } 1774 } else if (y > t) { 1775 do { 1776 --x; 1777 y = x - leapcorr(&x); 1778 } while (y > t); 1779 if (t != y) { 1780 rwlock_unlock(&lcl_lock); 1781 return x + 1; 1782 } 1783 } 1784 rwlock_unlock(&lcl_lock); 1785 return x; 1786 } 1787 1788 #endif /* defined STD_INSPIRED */ 1789