1 /* $NetBSD: localtime.c,v 1.100 2015/10/29 19:18:32 christos Exp $ */ 2 3 /* 4 ** This file is in the public domain, so clarified as of 5 ** 1996-06-05 by Arthur David Olson. 6 */ 7 8 #include <sys/cdefs.h> 9 #if defined(LIBC_SCCS) && !defined(lint) 10 #if 0 11 static char elsieid[] = "@(#)localtime.c 8.17"; 12 #else 13 __RCSID("$NetBSD: localtime.c,v 1.100 2015/10/29 19:18:32 christos Exp $"); 14 #endif 15 #endif /* LIBC_SCCS and not lint */ 16 17 /* 18 ** Leap second handling from Bradley White. 19 ** POSIX-style TZ environment variable handling from Guy Harris. 20 */ 21 22 /*LINTLIBRARY*/ 23 24 #include "namespace.h" 25 #include <assert.h> 26 #define LOCALTIME_IMPLEMENTATION 27 #include "private.h" 28 29 #include "tzfile.h" 30 #include "fcntl.h" 31 #include "reentrant.h" 32 33 #if NETBSD_INSPIRED 34 # define NETBSD_INSPIRED_EXTERN 35 #else 36 # define NETBSD_INSPIRED_EXTERN static 37 #endif 38 39 #if defined(__weak_alias) 40 __weak_alias(daylight,_daylight) 41 __weak_alias(tzname,_tzname) 42 #endif 43 44 #ifndef TZ_ABBR_MAX_LEN 45 #define TZ_ABBR_MAX_LEN 16 46 #endif /* !defined TZ_ABBR_MAX_LEN */ 47 48 #ifndef TZ_ABBR_CHAR_SET 49 #define TZ_ABBR_CHAR_SET \ 50 "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 :+-._" 51 #endif /* !defined TZ_ABBR_CHAR_SET */ 52 53 #ifndef TZ_ABBR_ERR_CHAR 54 #define TZ_ABBR_ERR_CHAR '_' 55 #endif /* !defined TZ_ABBR_ERR_CHAR */ 56 57 /* 58 ** SunOS 4.1.1 headers lack O_BINARY. 59 */ 60 61 #ifdef O_BINARY 62 #define OPEN_MODE (O_RDONLY | O_BINARY | O_CLOEXEC) 63 #endif /* defined O_BINARY */ 64 #ifndef O_BINARY 65 #define OPEN_MODE (O_RDONLY | O_CLOEXEC) 66 #endif /* !defined O_BINARY */ 67 68 #ifndef WILDABBR 69 /* 70 ** Someone might make incorrect use of a time zone abbreviation: 71 ** 1. They might reference tzname[0] before calling tzset (explicitly 72 ** or implicitly). 73 ** 2. They might reference tzname[1] before calling tzset (explicitly 74 ** or implicitly). 75 ** 3. They might reference tzname[1] after setting to a time zone 76 ** in which Daylight Saving Time is never observed. 77 ** 4. They might reference tzname[0] after setting to a time zone 78 ** in which Standard Time is never observed. 79 ** 5. They might reference tm.TM_ZONE after calling offtime. 80 ** What's best to do in the above cases is open to debate; 81 ** for now, we just set things up so that in any of the five cases 82 ** WILDABBR is used. Another possibility: initialize tzname[0] to the 83 ** string "tzname[0] used before set", and similarly for the other cases. 84 ** And another: initialize tzname[0] to "ERA", with an explanation in the 85 ** manual page of what this "time zone abbreviation" means (doing this so 86 ** that tzname[0] has the "normal" length of three characters). 87 */ 88 #define WILDABBR " " 89 #endif /* !defined WILDABBR */ 90 91 static const char wildabbr[] = WILDABBR; 92 93 static const char gmt[] = "GMT"; 94 95 /* 96 ** The DST rules to use if TZ has no rules and we can't load TZDEFRULES. 97 ** We default to US rules as of 1999-08-17. 98 ** POSIX 1003.1 section 8.1.1 says that the default DST rules are 99 ** implementation dependent; for historical reasons, US rules are a 100 ** common default. 101 */ 102 #ifndef TZDEFRULESTRING 103 #define TZDEFRULESTRING ",M4.1.0,M10.5.0" 104 #endif /* !defined TZDEFDST */ 105 106 struct ttinfo { /* time type information */ 107 int_fast32_t tt_gmtoff; /* UT offset in seconds */ 108 bool tt_isdst; /* used to set tm_isdst */ 109 int tt_abbrind; /* abbreviation list index */ 110 bool tt_ttisstd; /* transition is std time */ 111 bool tt_ttisgmt; /* transition is UT */ 112 }; 113 114 struct lsinfo { /* leap second information */ 115 time_t ls_trans; /* transition time */ 116 int_fast64_t ls_corr; /* correction to apply */ 117 }; 118 119 #define SMALLEST(a, b) (((a) < (b)) ? (a) : (b)) 120 #define BIGGEST(a, b) (((a) > (b)) ? (a) : (b)) 121 122 #ifdef TZNAME_MAX 123 #define MY_TZNAME_MAX TZNAME_MAX 124 #endif /* defined TZNAME_MAX */ 125 #ifndef TZNAME_MAX 126 #define MY_TZNAME_MAX 255 127 #endif /* !defined TZNAME_MAX */ 128 129 #define state __state 130 struct state { 131 int leapcnt; 132 int timecnt; 133 int typecnt; 134 int charcnt; 135 bool goback; 136 bool goahead; 137 time_t ats[TZ_MAX_TIMES]; 138 unsigned char types[TZ_MAX_TIMES]; 139 struct ttinfo ttis[TZ_MAX_TYPES]; 140 char chars[/*CONSTCOND*/BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, 141 sizeof gmt), (2 * (MY_TZNAME_MAX + 1)))]; 142 struct lsinfo lsis[TZ_MAX_LEAPS]; 143 int defaulttype; /* for early times or if no transitions */ 144 }; 145 146 enum r_type { 147 JULIAN_DAY, /* Jn = Julian day */ 148 DAY_OF_YEAR, /* n = day of year */ 149 MONTH_NTH_DAY_OF_WEEK /* Mm.n.d = month, week, day of week */ 150 }; 151 152 struct rule { 153 enum r_type r_type; /* type of rule */ 154 int r_day; /* day number of rule */ 155 int r_week; /* week number of rule */ 156 int r_mon; /* month number of rule */ 157 int_fast32_t r_time; /* transition time of rule */ 158 }; 159 160 static struct tm *gmtsub(struct state const *, time_t const *, int_fast32_t, 161 struct tm *); 162 static bool increment_overflow(int *, int); 163 static bool increment_overflow_time(time_t *, int_fast32_t); 164 static bool normalize_overflow32(int_fast32_t *, int *, int); 165 static struct tm *timesub(time_t const *, int_fast32_t, struct state const *, 166 struct tm *); 167 static bool typesequiv(struct state const *, int, int); 168 static bool tzparse(char const *, struct state *, bool); 169 170 static timezone_t lclptr; 171 static timezone_t gmtptr; 172 173 #ifndef TZ_STRLEN_MAX 174 #define TZ_STRLEN_MAX 255 175 #endif /* !defined TZ_STRLEN_MAX */ 176 177 static char lcl_TZname[TZ_STRLEN_MAX + 1]; 178 static int lcl_is_set; 179 180 #if !defined(__LIBC12_SOURCE__) 181 182 __aconst char * tzname[2] = { 183 (__aconst char *)__UNCONST(wildabbr), 184 (__aconst char *)__UNCONST(wildabbr) 185 }; 186 187 #else 188 189 extern __aconst char * tzname[2]; 190 191 #endif 192 193 #ifdef _REENTRANT 194 static rwlock_t lcl_lock = RWLOCK_INITIALIZER; 195 #endif 196 197 /* 198 ** Section 4.12.3 of X3.159-1989 requires that 199 ** Except for the strftime function, these functions [asctime, 200 ** ctime, gmtime, localtime] return values in one of two static 201 ** objects: a broken-down time structure and an array of char. 202 ** Thanks to Paul Eggert for noting this. 203 */ 204 205 static struct tm tm; 206 207 #ifdef USG_COMPAT 208 #if !defined(__LIBC12_SOURCE__) 209 long timezone = 0; 210 int daylight = 0; 211 #else 212 extern int daylight; 213 extern long timezone __RENAME(__timezone13); 214 #endif 215 #endif /* defined USG_COMPAT */ 216 217 #ifdef ALTZONE 218 long altzone = 0; 219 #endif /* defined ALTZONE */ 220 221 /* Initialize *S to a value based on GMTOFF, ISDST, and ABBRIND. */ 222 static void 223 init_ttinfo(struct ttinfo *s, int_fast32_t gmtoff, bool isdst, int abbrind) 224 { 225 s->tt_gmtoff = gmtoff; 226 s->tt_isdst = isdst; 227 s->tt_abbrind = abbrind; 228 s->tt_ttisstd = false; 229 s->tt_ttisgmt = false; 230 } 231 232 static int_fast32_t 233 detzcode(const char *const codep) 234 { 235 int_fast32_t result; 236 int i; 237 int_fast32_t one = 1; 238 int_fast32_t halfmaxval = one << (32 - 2); 239 int_fast32_t maxval = halfmaxval - 1 + halfmaxval; 240 int_fast32_t minval = -1 - maxval; 241 242 result = codep[0] & 0x7f; 243 for (i = 1; i < 4; ++i) 244 result = (result << 8) | (codep[i] & 0xff); 245 246 if (codep[0] & 0x80) { 247 /* Do two's-complement negation even on non-two's-complement machines. 248 If the result would be minval - 1, return minval. */ 249 result -= !TWOS_COMPLEMENT(int_fast32_t) && result != 0; 250 result += minval; 251 } 252 return result; 253 } 254 255 static int_fast64_t 256 detzcode64(const char *const codep) 257 { 258 int_fast64_t result; 259 int i; 260 int_fast64_t one = 1; 261 int_fast64_t halfmaxval = one << (64 - 2); 262 int_fast64_t maxval = halfmaxval - 1 + halfmaxval; 263 int_fast64_t minval = -TWOS_COMPLEMENT(int_fast64_t) - maxval; 264 265 result = codep[0] & 0x7f; 266 for (i = 1; i < 8; ++i) 267 result = (result << 8) | (codep[i] & 0xff); 268 269 if (codep[0] & 0x80) { 270 /* Do two's-complement negation even on non-two's-complement machines. 271 If the result would be minval - 1, return minval. */ 272 result -= !TWOS_COMPLEMENT(int_fast64_t) && result != 0; 273 result += minval; 274 } 275 return result; 276 } 277 278 const char * 279 tzgetname(const timezone_t sp, int isdst) 280 { 281 int i; 282 for (i = 0; i < sp->timecnt; ++i) { 283 const struct ttinfo *const ttisp = &sp->ttis[sp->types[i]]; 284 285 if (ttisp->tt_isdst == isdst) 286 return &sp->chars[ttisp->tt_abbrind]; 287 } 288 errno = ESRCH; 289 return NULL; 290 } 291 292 long 293 tzgetgmtoff(const timezone_t sp, int isdst) 294 { 295 int i; 296 long l = -1; 297 for (i = 0; i < sp->timecnt; ++i) { 298 const struct ttinfo *const ttisp = &sp->ttis[sp->types[i]]; 299 300 if (ttisp->tt_isdst == isdst) { 301 l = ttisp->tt_gmtoff; 302 if (sp->types[i] != 0) 303 return l; 304 } 305 } 306 if (l == -1) 307 errno = ESRCH; 308 return l; 309 } 310 311 static void 312 scrub_abbrs(struct state *sp) 313 { 314 int i; 315 316 /* 317 ** First, replace bogus characters. 318 */ 319 for (i = 0; i < sp->charcnt; ++i) 320 if (strchr(TZ_ABBR_CHAR_SET, sp->chars[i]) == NULL) 321 sp->chars[i] = TZ_ABBR_ERR_CHAR; 322 /* 323 ** Second, truncate long abbreviations. 324 */ 325 for (i = 0; i < sp->typecnt; ++i) { 326 const struct ttinfo * const ttisp = &sp->ttis[i]; 327 char * cp = &sp->chars[ttisp->tt_abbrind]; 328 329 if (strlen(cp) > TZ_ABBR_MAX_LEN && 330 strcmp(cp, GRANDPARENTED) != 0) 331 *(cp + TZ_ABBR_MAX_LEN) = '\0'; 332 } 333 } 334 335 static void 336 update_tzname_etc(const struct state *sp, const struct ttinfo *ttisp) 337 { 338 tzname[ttisp->tt_isdst] = __UNCONST(&sp->chars[ttisp->tt_abbrind]); 339 #ifdef USG_COMPAT 340 if (!ttisp->tt_isdst) 341 timezone = - ttisp->tt_gmtoff; 342 #endif 343 #ifdef ALTZONE 344 if (ttisp->tt_isdst) 345 altzone = - ttisp->tt_gmtoff; 346 #endif /* defined ALTZONE */ 347 } 348 349 static void 350 settzname(void) 351 { 352 timezone_t const sp = lclptr; 353 int i; 354 355 tzname[0] = (__aconst char *)__UNCONST(wildabbr); 356 tzname[1] = (__aconst char *)__UNCONST(wildabbr); 357 #ifdef USG_COMPAT 358 daylight = 0; 359 timezone = 0; 360 #endif /* defined USG_COMPAT */ 361 #ifdef ALTZONE 362 altzone = 0; 363 #endif /* defined ALTZONE */ 364 if (sp == NULL) { 365 tzname[0] = tzname[1] = (__aconst char *)__UNCONST(gmt); 366 return; 367 } 368 /* 369 ** And to get the latest zone names into tzname. . . 370 */ 371 for (i = 0; i < sp->typecnt; ++i) 372 update_tzname_etc(sp, &sp->ttis[i]); 373 374 for (i = 0; i < sp->timecnt; ++i) { 375 const struct ttinfo * const ttisp = &sp->ttis[sp->types[i]]; 376 update_tzname_etc(sp, ttisp); 377 #ifdef USG_COMPAT 378 if (ttisp->tt_isdst) 379 daylight = 1; 380 #endif /* defined USG_COMPAT */ 381 } 382 } 383 384 static bool 385 differ_by_repeat(const time_t t1, const time_t t0) 386 { 387 if (TYPE_BIT(time_t) - TYPE_SIGNED(time_t) < SECSPERREPEAT_BITS) 388 return 0; 389 return (int_fast64_t)t1 - (int_fast64_t)t0 == SECSPERREPEAT; 390 } 391 392 union input_buffer { 393 /* The first part of the buffer, interpreted as a header. */ 394 struct tzhead tzhead; 395 396 /* The entire buffer. */ 397 char buf[2 * sizeof(struct tzhead) + 2 * sizeof (struct state) 398 + 4 * TZ_MAX_TIMES]; 399 }; 400 401 /* Local storage needed for 'tzloadbody'. */ 402 union local_storage { 403 /* The file name to be opened. */ 404 char fullname[FILENAME_MAX + 1]; 405 406 /* The results of analyzing the file's contents after it is opened. */ 407 struct { 408 /* The input buffer. */ 409 union input_buffer u; 410 411 /* A temporary state used for parsing a TZ string in the file. */ 412 struct state st; 413 } u; 414 }; 415 416 /* Load tz data from the file named NAME into *SP. Read extended 417 format if DOEXTEND. Use *LSP for temporary storage. Return 0 on 418 success, an errno value on failure. */ 419 static int 420 tzloadbody(char const *name, struct state *sp, bool doextend, 421 union local_storage *lsp) 422 { 423 int i; 424 int fid; 425 int stored; 426 ssize_t nread; 427 bool doaccess; 428 char *fullname = lsp->fullname; 429 union input_buffer *up = &lsp->u.u; 430 size_t tzheadsize = sizeof(struct tzhead); 431 432 sp->goback = sp->goahead = false; 433 434 if (! name) { 435 name = TZDEFAULT; 436 if (! name) 437 return EINVAL; 438 } 439 440 if (name[0] == ':') 441 ++name; 442 doaccess = name[0] == '/'; 443 if (!doaccess) { 444 char const *p = TZDIR; 445 if (! p) 446 return EINVAL; 447 if (sizeof lsp->fullname - 1 <= strlen(p) + strlen(name)) 448 return ENAMETOOLONG; 449 strcpy(fullname, p); 450 strcat(fullname, "/"); 451 strcat(fullname, name); 452 /* Set doaccess if '.' (as in "../") shows up in name. */ 453 if (strchr(name, '.')) 454 doaccess = true; 455 name = fullname; 456 } 457 if (doaccess && access(name, R_OK) != 0) 458 return errno; 459 460 fid = open(name, OPEN_MODE); 461 if (fid < 0) 462 return errno; 463 nread = read(fid, up->buf, sizeof up->buf); 464 if (nread < (ssize_t)tzheadsize) { 465 int err = nread < 0 ? errno : EINVAL; 466 close(fid); 467 return err; 468 } 469 if (close(fid) < 0) 470 return errno; 471 for (stored = 4; stored <= 8; stored *= 2) { 472 int_fast32_t ttisstdcnt = detzcode(up->tzhead.tzh_ttisstdcnt); 473 int_fast32_t ttisgmtcnt = detzcode(up->tzhead.tzh_ttisgmtcnt); 474 int_fast32_t leapcnt = detzcode(up->tzhead.tzh_leapcnt); 475 int_fast32_t timecnt = detzcode(up->tzhead.tzh_timecnt); 476 int_fast32_t typecnt = detzcode(up->tzhead.tzh_typecnt); 477 int_fast32_t charcnt = detzcode(up->tzhead.tzh_charcnt); 478 char const *p = up->buf + tzheadsize; 479 if (! (0 <= leapcnt && leapcnt < TZ_MAX_LEAPS 480 && 0 < typecnt && typecnt < TZ_MAX_TYPES 481 && 0 <= timecnt && timecnt < TZ_MAX_TIMES 482 && 0 <= charcnt && charcnt < TZ_MAX_CHARS 483 && (ttisstdcnt == typecnt || ttisstdcnt == 0) 484 && (ttisgmtcnt == typecnt || ttisgmtcnt == 0))) 485 return EINVAL; 486 if ((size_t)nread 487 < (tzheadsize /* struct tzhead */ 488 + timecnt * stored /* ats */ 489 + timecnt /* types */ 490 + typecnt * 6 /* ttinfos */ 491 + charcnt /* chars */ 492 + leapcnt * (stored + 4) /* lsinfos */ 493 + ttisstdcnt /* ttisstds */ 494 + ttisgmtcnt)) /* ttisgmts */ 495 return EINVAL; 496 sp->leapcnt = leapcnt; 497 sp->timecnt = timecnt; 498 sp->typecnt = typecnt; 499 sp->charcnt = charcnt; 500 501 /* Read transitions, discarding those out of time_t range. 502 But pretend the last transition before time_t_min 503 occurred at time_t_min. */ 504 timecnt = 0; 505 for (i = 0; i < sp->timecnt; ++i) { 506 int_fast64_t at 507 = stored == 4 ? detzcode(p) : detzcode64(p); 508 sp->types[i] = at <= time_t_max; 509 if (sp->types[i]) { 510 time_t attime 511 = ((TYPE_SIGNED(time_t) ? 512 at < time_t_min : at < 0) 513 ? time_t_min : (time_t)at); 514 if (timecnt && attime <= sp->ats[timecnt - 1]) { 515 if (attime < sp->ats[timecnt - 1]) 516 return EINVAL; 517 sp->types[i - 1] = 0; 518 timecnt--; 519 } 520 sp->ats[timecnt++] = attime; 521 } 522 p += stored; 523 } 524 525 timecnt = 0; 526 for (i = 0; i < sp->timecnt; ++i) { 527 unsigned char typ = *p++; 528 if (sp->typecnt <= typ) 529 return EINVAL; 530 if (sp->types[i]) 531 sp->types[timecnt++] = typ; 532 } 533 sp->timecnt = timecnt; 534 for (i = 0; i < sp->typecnt; ++i) { 535 struct ttinfo * ttisp; 536 unsigned char isdst, abbrind; 537 538 ttisp = &sp->ttis[i]; 539 ttisp->tt_gmtoff = detzcode(p); 540 p += 4; 541 isdst = *p++; 542 if (! (isdst < 2)) 543 return EINVAL; 544 ttisp->tt_isdst = isdst; 545 abbrind = *p++; 546 if (! (abbrind < sp->charcnt)) 547 return EINVAL; 548 ttisp->tt_abbrind = abbrind; 549 } 550 for (i = 0; i < sp->charcnt; ++i) 551 sp->chars[i] = *p++; 552 sp->chars[i] = '\0'; /* ensure '\0' at end */ 553 554 /* Read leap seconds, discarding those out of time_t range. */ 555 leapcnt = 0; 556 for (i = 0; i < sp->leapcnt; ++i) { 557 int_fast64_t tr = stored == 4 ? detzcode(p) : 558 detzcode64(p); 559 int_fast32_t corr = detzcode(p + stored); 560 p += stored + 4; 561 if (tr <= time_t_max) { 562 time_t trans = ((TYPE_SIGNED(time_t) ? 563 tr < time_t_min : tr < 0) 564 ? time_t_min : (time_t)tr); 565 if (leapcnt && trans <= 566 sp->lsis[leapcnt - 1].ls_trans) { 567 if (trans < 568 sp->lsis[leapcnt - 1].ls_trans) 569 return EINVAL; 570 leapcnt--; 571 } 572 sp->lsis[leapcnt].ls_trans = trans; 573 sp->lsis[leapcnt].ls_corr = corr; 574 leapcnt++; 575 } 576 } 577 sp->leapcnt = leapcnt; 578 579 for (i = 0; i < sp->typecnt; ++i) { 580 struct ttinfo * ttisp; 581 582 ttisp = &sp->ttis[i]; 583 if (ttisstdcnt == 0) 584 ttisp->tt_ttisstd = false; 585 else { 586 if (*p != true && *p != false) 587 return EINVAL; 588 ttisp->tt_ttisstd = *p++; 589 } 590 } 591 for (i = 0; i < sp->typecnt; ++i) { 592 struct ttinfo * ttisp; 593 594 ttisp = &sp->ttis[i]; 595 if (ttisgmtcnt == 0) 596 ttisp->tt_ttisgmt = false; 597 else { 598 if (*p != true && *p != false) 599 return EINVAL; 600 ttisp->tt_ttisgmt = *p++; 601 } 602 } 603 /* 604 ** If this is an old file, we're done. 605 */ 606 if (up->tzhead.tzh_version[0] == '\0') 607 break; 608 nread -= p - up->buf; 609 memmove(up->buf, p, (size_t)nread); 610 } 611 if (doextend && nread > 2 && 612 up->buf[0] == '\n' && up->buf[nread - 1] == '\n' && 613 sp->typecnt + 2 <= TZ_MAX_TYPES) { 614 struct state *ts = &lsp->u.st; 615 616 up->buf[nread - 1] = '\0'; 617 if (tzparse(&up->buf[1], ts, false) 618 && ts->typecnt == 2) { 619 620 /* Attempt to reuse existing abbreviations. 621 Without this, America/Anchorage would stop 622 working after 2037 when TZ_MAX_CHARS is 50, as 623 sp->charcnt equals 42 (for LMT CAT CAWT CAPT AHST 624 AHDT YST AKDT AKST) and ts->charcnt equals 10 625 (for AKST AKDT). Reusing means sp->charcnt can 626 stay 42 in this example. */ 627 int gotabbr = 0; 628 int charcnt = sp->charcnt; 629 for (i = 0; i < 2; i++) { 630 char *tsabbr = ts->chars + ts->ttis[i].tt_abbrind; 631 int j; 632 for (j = 0; j < charcnt; j++) 633 if (strcmp(sp->chars + j, tsabbr) == 0) { 634 ts->ttis[i].tt_abbrind = j; 635 gotabbr++; 636 break; 637 } 638 if (! (j < charcnt)) { 639 size_t tsabbrlen = strlen(tsabbr); 640 if (j + tsabbrlen < TZ_MAX_CHARS) { 641 strcpy(sp->chars + j, tsabbr); 642 charcnt = (int_fast32_t)(j + tsabbrlen + 1); 643 ts->ttis[i].tt_abbrind = j; 644 gotabbr++; 645 } 646 } 647 } 648 if (gotabbr == 2) { 649 sp->charcnt = charcnt; 650 for (i = 0; i < ts->timecnt; i++) 651 if (sp->ats[sp->timecnt - 1] < ts->ats[i]) 652 break; 653 while (i < ts->timecnt 654 && sp->timecnt < TZ_MAX_TIMES) { 655 sp->ats[sp->timecnt] = ts->ats[i]; 656 sp->types[sp->timecnt] = (sp->typecnt 657 + ts->types[i]); 658 sp->timecnt++; 659 i++; 660 } 661 sp->ttis[sp->typecnt++] = ts->ttis[0]; 662 sp->ttis[sp->typecnt++] = ts->ttis[1]; 663 } 664 } 665 } 666 if (sp->timecnt > 1) { 667 for (i = 1; i < sp->timecnt; ++i) 668 if (typesequiv(sp, sp->types[i], sp->types[0]) && 669 differ_by_repeat(sp->ats[i], sp->ats[0])) { 670 sp->goback = true; 671 break; 672 } 673 for (i = sp->timecnt - 2; i >= 0; --i) 674 if (typesequiv(sp, sp->types[sp->timecnt - 1], 675 sp->types[i]) && 676 differ_by_repeat(sp->ats[sp->timecnt - 1], 677 sp->ats[i])) { 678 sp->goahead = true; 679 break; 680 } 681 } 682 /* 683 ** If type 0 is is unused in transitions, 684 ** it's the type to use for early times. 685 */ 686 for (i = 0; i < sp->timecnt; ++i) 687 if (sp->types[i] == 0) 688 break; 689 i = i < sp->timecnt ? -1 : 0; 690 /* 691 ** Absent the above, 692 ** if there are transition times 693 ** and the first transition is to a daylight time 694 ** find the standard type less than and closest to 695 ** the type of the first transition. 696 */ 697 if (i < 0 && sp->timecnt > 0 && sp->ttis[sp->types[0]].tt_isdst) { 698 i = sp->types[0]; 699 while (--i >= 0) 700 if (!sp->ttis[i].tt_isdst) 701 break; 702 } 703 /* 704 ** If no result yet, find the first standard type. 705 ** If there is none, punt to type zero. 706 */ 707 if (i < 0) { 708 i = 0; 709 while (sp->ttis[i].tt_isdst) 710 if (++i >= sp->typecnt) { 711 i = 0; 712 break; 713 } 714 } 715 sp->defaulttype = i; 716 return 0; 717 } 718 719 /* Load tz data from the file named NAME into *SP. Read extended 720 format if DOEXTEND. Return 0 on success, an errno value on failure. */ 721 static int 722 tzload(char const *name, struct state *sp, bool doextend) 723 { 724 union local_storage *lsp = malloc(sizeof *lsp); 725 if (!lsp) 726 return errno; 727 else { 728 int err = tzloadbody(name, sp, doextend, lsp); 729 free(lsp); 730 return err; 731 } 732 } 733 734 static bool 735 typesequiv(const struct state *sp, int a, int b) 736 { 737 bool result; 738 739 if (sp == NULL || 740 a < 0 || a >= sp->typecnt || 741 b < 0 || b >= sp->typecnt) 742 result = false; 743 else { 744 const struct ttinfo * ap = &sp->ttis[a]; 745 const struct ttinfo * bp = &sp->ttis[b]; 746 result = ap->tt_gmtoff == bp->tt_gmtoff && 747 ap->tt_isdst == bp->tt_isdst && 748 ap->tt_ttisstd == bp->tt_ttisstd && 749 ap->tt_ttisgmt == bp->tt_ttisgmt && 750 strcmp(&sp->chars[ap->tt_abbrind], 751 &sp->chars[bp->tt_abbrind]) == 0; 752 } 753 return result; 754 } 755 756 static const int mon_lengths[2][MONSPERYEAR] = { 757 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, 758 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } 759 }; 760 761 static const int year_lengths[2] = { 762 DAYSPERNYEAR, DAYSPERLYEAR 763 }; 764 765 /* 766 ** Given a pointer into a time zone string, scan until a character that is not 767 ** a valid character in a zone name is found. Return a pointer to that 768 ** character. 769 */ 770 771 static const char * ATTRIBUTE_PURE 772 getzname(const char *strp) 773 { 774 char c; 775 776 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && 777 c != '+') 778 ++strp; 779 return strp; 780 } 781 782 /* 783 ** Given a pointer into an extended time zone string, scan until the ending 784 ** delimiter of the zone name is located. Return a pointer to the delimiter. 785 ** 786 ** As with getzname above, the legal character set is actually quite 787 ** restricted, with other characters producing undefined results. 788 ** We don't do any checking here; checking is done later in common-case code. 789 */ 790 791 static const char * ATTRIBUTE_PURE 792 getqzname(const char *strp, const int delim) 793 { 794 int c; 795 796 while ((c = *strp) != '\0' && c != delim) 797 ++strp; 798 return strp; 799 } 800 801 /* 802 ** Given a pointer into a time zone string, extract a number from that string. 803 ** Check that the number is within a specified range; if it is not, return 804 ** NULL. 805 ** Otherwise, return a pointer to the first character not part of the number. 806 */ 807 808 static const char * 809 getnum(const char *strp, int *const nump, const int min, const int max) 810 { 811 char c; 812 int num; 813 814 if (strp == NULL || !is_digit(c = *strp)) { 815 errno = EINVAL; 816 return NULL; 817 } 818 num = 0; 819 do { 820 num = num * 10 + (c - '0'); 821 if (num > max) { 822 errno = EOVERFLOW; 823 return NULL; /* illegal value */ 824 } 825 c = *++strp; 826 } while (is_digit(c)); 827 if (num < min) { 828 errno = EINVAL; 829 return NULL; /* illegal value */ 830 } 831 *nump = num; 832 return strp; 833 } 834 835 /* 836 ** Given a pointer into a time zone string, extract a number of seconds, 837 ** in hh[:mm[:ss]] form, from the string. 838 ** If any error occurs, return NULL. 839 ** Otherwise, return a pointer to the first character not part of the number 840 ** of seconds. 841 */ 842 843 static const char * 844 getsecs(const char *strp, int_fast32_t *const secsp) 845 { 846 int num; 847 848 /* 849 ** 'HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like 850 ** "M10.4.6/26", which does not conform to Posix, 851 ** but which specifies the equivalent of 852 ** "02:00 on the first Sunday on or after 23 Oct". 853 */ 854 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); 855 if (strp == NULL) 856 return NULL; 857 *secsp = num * (int_fast32_t) SECSPERHOUR; 858 if (*strp == ':') { 859 ++strp; 860 strp = getnum(strp, &num, 0, MINSPERHOUR - 1); 861 if (strp == NULL) 862 return NULL; 863 *secsp += num * SECSPERMIN; 864 if (*strp == ':') { 865 ++strp; 866 /* 'SECSPERMIN' allows for leap seconds. */ 867 strp = getnum(strp, &num, 0, SECSPERMIN); 868 if (strp == NULL) 869 return NULL; 870 *secsp += num; 871 } 872 } 873 return strp; 874 } 875 876 /* 877 ** Given a pointer into a time zone string, extract an offset, in 878 ** [+-]hh[:mm[:ss]] form, from the string. 879 ** If any error occurs, return NULL. 880 ** Otherwise, return a pointer to the first character not part of the time. 881 */ 882 883 static const char * 884 getoffset(const char *strp, int_fast32_t *const offsetp) 885 { 886 bool neg = false; 887 888 if (*strp == '-') { 889 neg = true; 890 ++strp; 891 } else if (*strp == '+') 892 ++strp; 893 strp = getsecs(strp, offsetp); 894 if (strp == NULL) 895 return NULL; /* illegal time */ 896 if (neg) 897 *offsetp = -*offsetp; 898 return strp; 899 } 900 901 /* 902 ** Given a pointer into a time zone string, extract a rule in the form 903 ** date[/time]. See POSIX section 8 for the format of "date" and "time". 904 ** If a valid rule is not found, return NULL. 905 ** Otherwise, return a pointer to the first character not part of the rule. 906 */ 907 908 static const char * 909 getrule(const char *strp, struct rule *const rulep) 910 { 911 if (*strp == 'J') { 912 /* 913 ** Julian day. 914 */ 915 rulep->r_type = JULIAN_DAY; 916 ++strp; 917 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); 918 } else if (*strp == 'M') { 919 /* 920 ** Month, week, day. 921 */ 922 rulep->r_type = MONTH_NTH_DAY_OF_WEEK; 923 ++strp; 924 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); 925 if (strp == NULL) 926 return NULL; 927 if (*strp++ != '.') 928 return NULL; 929 strp = getnum(strp, &rulep->r_week, 1, 5); 930 if (strp == NULL) 931 return NULL; 932 if (*strp++ != '.') 933 return NULL; 934 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); 935 } else if (is_digit(*strp)) { 936 /* 937 ** Day of year. 938 */ 939 rulep->r_type = DAY_OF_YEAR; 940 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); 941 } else return NULL; /* invalid format */ 942 if (strp == NULL) 943 return NULL; 944 if (*strp == '/') { 945 /* 946 ** Time specified. 947 */ 948 ++strp; 949 strp = getoffset(strp, &rulep->r_time); 950 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ 951 return strp; 952 } 953 954 /* 955 ** Given a year, a rule, and the offset from UT at the time that rule takes 956 ** effect, calculate the year-relative time that rule takes effect. 957 */ 958 959 static int_fast32_t ATTRIBUTE_PURE 960 transtime(const int year, const struct rule *const rulep, 961 const int_fast32_t offset) 962 { 963 bool leapyear; 964 int_fast32_t value; 965 int i; 966 int d, m1, yy0, yy1, yy2, dow; 967 968 INITIALIZE(value); 969 leapyear = isleap(year); 970 switch (rulep->r_type) { 971 972 case JULIAN_DAY: 973 /* 974 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap 975 ** years. 976 ** In non-leap years, or if the day number is 59 or less, just 977 ** add SECSPERDAY times the day number-1 to the time of 978 ** January 1, midnight, to get the day. 979 */ 980 value = (rulep->r_day - 1) * SECSPERDAY; 981 if (leapyear && rulep->r_day >= 60) 982 value += SECSPERDAY; 983 break; 984 985 case DAY_OF_YEAR: 986 /* 987 ** n - day of year. 988 ** Just add SECSPERDAY times the day number to the time of 989 ** January 1, midnight, to get the day. 990 */ 991 value = rulep->r_day * SECSPERDAY; 992 break; 993 994 case MONTH_NTH_DAY_OF_WEEK: 995 /* 996 ** Mm.n.d - nth "dth day" of month m. 997 */ 998 999 /* 1000 ** Use Zeller's Congruence to get day-of-week of first day of 1001 ** month. 1002 */ 1003 m1 = (rulep->r_mon + 9) % 12 + 1; 1004 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; 1005 yy1 = yy0 / 100; 1006 yy2 = yy0 % 100; 1007 dow = ((26 * m1 - 2) / 10 + 1008 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; 1009 if (dow < 0) 1010 dow += DAYSPERWEEK; 1011 1012 /* 1013 ** "dow" is the day-of-week of the first day of the month. Get 1014 ** the day-of-month (zero-origin) of the first "dow" day of the 1015 ** month. 1016 */ 1017 d = rulep->r_day - dow; 1018 if (d < 0) 1019 d += DAYSPERWEEK; 1020 for (i = 1; i < rulep->r_week; ++i) { 1021 if (d + DAYSPERWEEK >= 1022 mon_lengths[leapyear][rulep->r_mon - 1]) 1023 break; 1024 d += DAYSPERWEEK; 1025 } 1026 1027 /* 1028 ** "d" is the day-of-month (zero-origin) of the day we want. 1029 */ 1030 value = d * SECSPERDAY; 1031 for (i = 0; i < rulep->r_mon - 1; ++i) 1032 value += mon_lengths[leapyear][i] * SECSPERDAY; 1033 break; 1034 } 1035 1036 /* 1037 ** "value" is the year-relative time of 00:00:00 UT on the day in 1038 ** question. To get the year-relative time of the specified local 1039 ** time on that day, add the transition time and the current offset 1040 ** from UT. 1041 */ 1042 return value + rulep->r_time + offset; 1043 } 1044 1045 /* 1046 ** Given a POSIX section 8-style TZ string, fill in the rule tables as 1047 ** appropriate. 1048 */ 1049 1050 static bool 1051 tzparse(const char *name, struct state *sp, bool lastditch) 1052 { 1053 const char * stdname; 1054 const char * dstname; 1055 size_t stdlen; 1056 size_t dstlen; 1057 size_t charcnt; 1058 int_fast32_t stdoffset; 1059 int_fast32_t dstoffset; 1060 char * cp; 1061 bool load_ok; 1062 1063 dstname = NULL; /* XXX gcc */ 1064 stdname = name; 1065 if (lastditch) { 1066 stdlen = sizeof gmt - 1; 1067 name += stdlen; 1068 stdoffset = 0; 1069 } else { 1070 if (*name == '<') { 1071 name++; 1072 stdname = name; 1073 name = getqzname(name, '>'); 1074 if (*name != '>') 1075 return false; 1076 stdlen = name - stdname; 1077 name++; 1078 } else { 1079 name = getzname(name); 1080 stdlen = name - stdname; 1081 } 1082 if (!stdlen) 1083 return false; 1084 name = getoffset(name, &stdoffset); 1085 if (name == NULL) 1086 return false; 1087 } 1088 charcnt = stdlen + 1; 1089 if (sizeof sp->chars < charcnt) 1090 return false; 1091 load_ok = tzload(TZDEFRULES, sp, false) == 0; 1092 if (!load_ok) 1093 sp->leapcnt = 0; /* so, we're off a little */ 1094 if (*name != '\0') { 1095 if (*name == '<') { 1096 dstname = ++name; 1097 name = getqzname(name, '>'); 1098 if (*name != '>') 1099 return false; 1100 dstlen = name - dstname; 1101 name++; 1102 } else { 1103 dstname = name; 1104 name = getzname(name); 1105 dstlen = name - dstname; /* length of DST zone name */ 1106 } 1107 if (!dstlen) 1108 return false; 1109 charcnt += dstlen + 1; 1110 if (sizeof sp->chars < charcnt) 1111 return false; 1112 if (*name != '\0' && *name != ',' && *name != ';') { 1113 name = getoffset(name, &dstoffset); 1114 if (name == NULL) 1115 return false; 1116 } else dstoffset = stdoffset - SECSPERHOUR; 1117 if (*name == '\0' && !load_ok) 1118 name = TZDEFRULESTRING; 1119 if (*name == ',' || *name == ';') { 1120 struct rule start; 1121 struct rule end; 1122 int year; 1123 int yearlim; 1124 int timecnt; 1125 time_t janfirst; 1126 1127 ++name; 1128 if ((name = getrule(name, &start)) == NULL) 1129 return false; 1130 if (*name++ != ',') 1131 return false; 1132 if ((name = getrule(name, &end)) == NULL) 1133 return false; 1134 if (*name != '\0') 1135 return false; 1136 sp->typecnt = 2; /* standard time and DST */ 1137 /* 1138 ** Two transitions per year, from EPOCH_YEAR forward. 1139 */ 1140 init_ttinfo(&sp->ttis[0], -dstoffset, true, 1141 (int)(stdlen + 1)); 1142 init_ttinfo(&sp->ttis[1], -stdoffset, false, 0); 1143 sp->defaulttype = 0; 1144 timecnt = 0; 1145 janfirst = 0; 1146 yearlim = EPOCH_YEAR + YEARSPERREPEAT; 1147 for (year = EPOCH_YEAR; year < yearlim; year++) { 1148 int_fast32_t 1149 starttime = transtime(year, &start, stdoffset), 1150 endtime = transtime(year, &end, dstoffset); 1151 int_fast32_t 1152 yearsecs = (year_lengths[isleap(year)] 1153 * SECSPERDAY); 1154 bool reversed = endtime < starttime; 1155 if (reversed) { 1156 int_fast32_t swap = starttime; 1157 starttime = endtime; 1158 endtime = swap; 1159 } 1160 if (reversed 1161 || (starttime < endtime 1162 && (endtime - starttime 1163 < (yearsecs 1164 + (stdoffset - dstoffset))))) { 1165 if (TZ_MAX_TIMES - 2 < timecnt) 1166 break; 1167 yearlim = year + YEARSPERREPEAT + 1; 1168 sp->ats[timecnt] = janfirst; 1169 if (increment_overflow_time 1170 (&sp->ats[timecnt], starttime)) 1171 break; 1172 sp->types[timecnt++] = reversed; 1173 sp->ats[timecnt] = janfirst; 1174 if (increment_overflow_time 1175 (&sp->ats[timecnt], endtime)) 1176 break; 1177 sp->types[timecnt++] = !reversed; 1178 } 1179 if (increment_overflow_time(&janfirst, yearsecs)) 1180 break; 1181 } 1182 sp->timecnt = timecnt; 1183 if (!timecnt) 1184 sp->typecnt = 1; /* Perpetual DST. */ 1185 } else { 1186 int_fast32_t theirstdoffset; 1187 int_fast32_t theirdstoffset; 1188 int_fast32_t theiroffset; 1189 bool isdst; 1190 int i; 1191 int j; 1192 1193 if (*name != '\0') 1194 return false; 1195 /* 1196 ** Initial values of theirstdoffset and theirdstoffset. 1197 */ 1198 theirstdoffset = 0; 1199 for (i = 0; i < sp->timecnt; ++i) { 1200 j = sp->types[i]; 1201 if (!sp->ttis[j].tt_isdst) { 1202 theirstdoffset = 1203 -sp->ttis[j].tt_gmtoff; 1204 break; 1205 } 1206 } 1207 theirdstoffset = 0; 1208 for (i = 0; i < sp->timecnt; ++i) { 1209 j = sp->types[i]; 1210 if (sp->ttis[j].tt_isdst) { 1211 theirdstoffset = 1212 -sp->ttis[j].tt_gmtoff; 1213 break; 1214 } 1215 } 1216 /* 1217 ** Initially we're assumed to be in standard time. 1218 */ 1219 isdst = false; 1220 theiroffset = theirstdoffset; 1221 /* 1222 ** Now juggle transition times and types 1223 ** tracking offsets as you do. 1224 */ 1225 for (i = 0; i < sp->timecnt; ++i) { 1226 j = sp->types[i]; 1227 sp->types[i] = sp->ttis[j].tt_isdst; 1228 if (sp->ttis[j].tt_ttisgmt) { 1229 /* No adjustment to transition time */ 1230 } else { 1231 /* 1232 ** If summer time is in effect, and the 1233 ** transition time was not specified as 1234 ** standard time, add the summer time 1235 ** offset to the transition time; 1236 ** otherwise, add the standard time 1237 ** offset to the transition time. 1238 */ 1239 /* 1240 ** Transitions from DST to DDST 1241 ** will effectively disappear since 1242 ** POSIX provides for only one DST 1243 ** offset. 1244 */ 1245 if (isdst && !sp->ttis[j].tt_ttisstd) { 1246 sp->ats[i] += (time_t) 1247 (dstoffset - theirdstoffset); 1248 } else { 1249 sp->ats[i] += (time_t) 1250 (stdoffset - theirstdoffset); 1251 } 1252 } 1253 theiroffset = -sp->ttis[j].tt_gmtoff; 1254 if (sp->ttis[j].tt_isdst) 1255 theirstdoffset = theiroffset; 1256 else theirdstoffset = theiroffset; 1257 } 1258 /* 1259 ** Finally, fill in ttis. 1260 */ 1261 init_ttinfo(&sp->ttis[0], -stdoffset, false, 0); 1262 init_ttinfo(&sp->ttis[1], -dstoffset, true, 1263 (int)(stdlen + 1)); 1264 sp->typecnt = 2; 1265 sp->defaulttype = 0; 1266 } 1267 } else { 1268 dstlen = 0; 1269 sp->typecnt = 1; /* only standard time */ 1270 sp->timecnt = 0; 1271 init_ttinfo(&sp->ttis[0], -stdoffset, false, 0); 1272 init_ttinfo(&sp->ttis[1], 0, false, 0); 1273 sp->defaulttype = 0; 1274 } 1275 sp->charcnt = (int)charcnt; 1276 cp = sp->chars; 1277 (void) memcpy(cp, stdname, stdlen); 1278 cp += stdlen; 1279 *cp++ = '\0'; 1280 if (dstlen != 0) { 1281 (void) memcpy(cp, dstname, dstlen); 1282 *(cp + dstlen) = '\0'; 1283 } 1284 return true; 1285 } 1286 1287 static void 1288 gmtload(struct state *const sp) 1289 { 1290 if (tzload(gmt, sp, true) != 0) 1291 (void) tzparse(gmt, sp, true); 1292 } 1293 1294 static int 1295 zoneinit(struct state *sp, char const *name) 1296 { 1297 if (name && ! name[0]) { 1298 /* 1299 ** User wants it fast rather than right. 1300 */ 1301 sp->leapcnt = 0; /* so, we're off a little */ 1302 sp->timecnt = 0; 1303 sp->typecnt = 0; 1304 sp->charcnt = 0; 1305 sp->goback = sp->goahead = false; 1306 init_ttinfo(&sp->ttis[0], 0, false, 0); 1307 strcpy(sp->chars, gmt); 1308 sp->defaulttype = 0; 1309 return 0; 1310 } else { 1311 int err = tzload(name, sp, true); 1312 if (err != 0 && name && name[0] != ':' && 1313 tzparse(name, sp, false)) 1314 err = 0; 1315 if (err == 0) 1316 scrub_abbrs(sp); 1317 return err; 1318 } 1319 } 1320 1321 static void 1322 tzsetlcl(char const *name) 1323 { 1324 struct state *sp = lclptr; 1325 int lcl = name ? strlen(name) < sizeof lcl_TZname : -1; 1326 if (lcl < 0 ? lcl_is_set < 0 1327 : 0 < lcl_is_set && strcmp(lcl_TZname, name) == 0) 1328 return; 1329 1330 if (! sp) 1331 lclptr = sp = malloc(sizeof *lclptr); 1332 if (sp) { 1333 if (zoneinit(sp, name) != 0) 1334 zoneinit(sp, ""); 1335 if (0 < lcl) 1336 strcpy(lcl_TZname, name); 1337 } 1338 settzname(); 1339 lcl_is_set = lcl; 1340 } 1341 1342 #ifdef STD_INSPIRED 1343 void 1344 tzsetwall(void) 1345 { 1346 rwlock_wrlock(&lcl_lock); 1347 tzsetlcl(NULL); 1348 rwlock_unlock(&lcl_lock); 1349 } 1350 #endif 1351 1352 static void 1353 tzset_unlocked(void) 1354 { 1355 tzsetlcl(getenv("TZ")); 1356 } 1357 1358 void 1359 tzset(void) 1360 { 1361 rwlock_wrlock(&lcl_lock); 1362 tzset_unlocked(); 1363 rwlock_unlock(&lcl_lock); 1364 } 1365 1366 static void 1367 gmtcheck(void) 1368 { 1369 static bool gmt_is_set; 1370 rwlock_wrlock(&lcl_lock); 1371 if (! gmt_is_set) { 1372 gmtptr = malloc(sizeof *gmtptr); 1373 if (gmtptr) 1374 gmtload(gmtptr); 1375 gmt_is_set = true; 1376 } 1377 rwlock_unlock(&lcl_lock); 1378 } 1379 1380 #if NETBSD_INSPIRED 1381 1382 timezone_t 1383 tzalloc(const char *name) 1384 { 1385 timezone_t sp = malloc(sizeof *sp); 1386 if (sp) { 1387 int err = zoneinit(sp, name); 1388 if (err != 0) { 1389 free(sp); 1390 errno = err; 1391 return NULL; 1392 } 1393 } 1394 return sp; 1395 } 1396 1397 void 1398 tzfree(timezone_t sp) 1399 { 1400 free(sp); 1401 } 1402 1403 /* 1404 ** NetBSD 6.1.4 has ctime_rz, but omit it because POSIX says ctime and 1405 ** ctime_r are obsolescent and have potential security problems that 1406 ** ctime_rz would share. Callers can instead use localtime_rz + strftime. 1407 ** 1408 ** NetBSD 6.1.4 has tzgetname, but omit it because it doesn't work 1409 ** in zones with three or more time zone abbreviations. 1410 ** Callers can instead use localtime_rz + strftime. 1411 */ 1412 1413 #endif 1414 1415 /* 1416 ** The easy way to behave "as if no library function calls" localtime 1417 ** is to not call it, so we drop its guts into "localsub", which can be 1418 ** freely called. (And no, the PANS doesn't require the above behavior, 1419 ** but it *is* desirable.) 1420 ** 1421 ** If successful and SETNAME is nonzero, 1422 ** set the applicable parts of tzname, timezone and altzone; 1423 ** however, it's OK to omit this step if the time zone is POSIX-compatible, 1424 ** since in that case tzset should have already done this step correctly. 1425 ** SETNAME's type is intfast32_t for compatibility with gmtsub, 1426 ** but it is actually a boolean and its value should be 0 or 1. 1427 */ 1428 1429 /*ARGSUSED*/ 1430 static struct tm * 1431 localsub(struct state const *sp, time_t const *timep, int_fast32_t setname, 1432 struct tm *const tmp) 1433 { 1434 const struct ttinfo * ttisp; 1435 int i; 1436 struct tm * result; 1437 const time_t t = *timep; 1438 1439 if (sp == NULL) { 1440 /* Don't bother to set tzname etc.; tzset has already done it. */ 1441 return gmtsub(gmtptr, timep, 0, tmp); 1442 } 1443 if ((sp->goback && t < sp->ats[0]) || 1444 (sp->goahead && t > sp->ats[sp->timecnt - 1])) { 1445 time_t newt = t; 1446 time_t seconds; 1447 time_t years; 1448 1449 if (t < sp->ats[0]) 1450 seconds = sp->ats[0] - t; 1451 else seconds = t - sp->ats[sp->timecnt - 1]; 1452 --seconds; 1453 years = (time_t)((seconds / SECSPERREPEAT + 1) * YEARSPERREPEAT); 1454 seconds = (time_t)(years * AVGSECSPERYEAR); 1455 if (t < sp->ats[0]) 1456 newt += seconds; 1457 else newt -= seconds; 1458 if (newt < sp->ats[0] || 1459 newt > sp->ats[sp->timecnt - 1]) { 1460 errno = EINVAL; 1461 return NULL; /* "cannot happen" */ 1462 } 1463 result = localsub(sp, &newt, setname, tmp); 1464 if (result) { 1465 int_fast64_t newy; 1466 1467 newy = result->tm_year; 1468 if (t < sp->ats[0]) 1469 newy -= years; 1470 else newy += years; 1471 if (! (INT_MIN <= newy && newy <= INT_MAX)) { 1472 errno = EOVERFLOW; 1473 return NULL; 1474 } 1475 result->tm_year = (int)newy; 1476 } 1477 return result; 1478 } 1479 if (sp->timecnt == 0 || t < sp->ats[0]) { 1480 i = sp->defaulttype; 1481 } else { 1482 int lo = 1; 1483 int hi = sp->timecnt; 1484 1485 while (lo < hi) { 1486 int mid = (lo + hi) / 2; 1487 1488 if (t < sp->ats[mid]) 1489 hi = mid; 1490 else lo = mid + 1; 1491 } 1492 i = (int) sp->types[lo - 1]; 1493 } 1494 ttisp = &sp->ttis[i]; 1495 /* 1496 ** To get (wrong) behavior that's compatible with System V Release 2.0 1497 ** you'd replace the statement below with 1498 ** t += ttisp->tt_gmtoff; 1499 ** timesub(&t, 0L, sp, tmp); 1500 */ 1501 result = timesub(&t, ttisp->tt_gmtoff, sp, tmp); 1502 if (result) { 1503 result->tm_isdst = ttisp->tt_isdst; 1504 #ifdef TM_ZONE 1505 result->TM_ZONE = __UNCONST(&sp->chars[ttisp->tt_abbrind]); 1506 #endif /* defined TM_ZONE */ 1507 if (setname) 1508 update_tzname_etc(sp, ttisp); 1509 } 1510 return result; 1511 } 1512 1513 #if NETBSD_INSPIRED 1514 1515 struct tm * 1516 localtime_rz(timezone_t sp, time_t const *timep, struct tm *tmp) 1517 { 1518 return localsub(sp, timep, 0, tmp); 1519 } 1520 1521 #endif 1522 1523 static struct tm * 1524 localtime_tzset(time_t const *timep, struct tm *tmp, bool setname) 1525 { 1526 rwlock_wrlock(&lcl_lock); 1527 if (setname || !lcl_is_set) 1528 tzset_unlocked(); 1529 tmp = localsub(lclptr, timep, setname, tmp); 1530 rwlock_unlock(&lcl_lock); 1531 return tmp; 1532 } 1533 1534 struct tm * 1535 localtime(const time_t *timep) 1536 { 1537 return localtime_tzset(timep, &tm, true); 1538 } 1539 1540 struct tm * 1541 localtime_r(const time_t * __restrict timep, struct tm *tmp) 1542 { 1543 return localtime_tzset(timep, tmp, false); 1544 } 1545 1546 /* 1547 ** gmtsub is to gmtime as localsub is to localtime. 1548 */ 1549 1550 static struct tm * 1551 gmtsub(struct state const *sp, const time_t *timep, int_fast32_t offset, 1552 struct tm *tmp) 1553 { 1554 struct tm * result; 1555 1556 result = timesub(timep, offset, gmtptr, tmp); 1557 #ifdef TM_ZONE 1558 /* 1559 ** Could get fancy here and deliver something such as 1560 ** "UT+xxxx" or "UT-xxxx" if offset is non-zero, 1561 ** but this is no time for a treasure hunt. 1562 */ 1563 if (result) 1564 result->TM_ZONE = offset ? __UNCONST(wildabbr) : gmtptr ? 1565 gmtptr->chars : __UNCONST(gmt); 1566 #endif /* defined TM_ZONE */ 1567 return result; 1568 } 1569 1570 1571 /* 1572 ** Re-entrant version of gmtime. 1573 */ 1574 1575 struct tm * 1576 gmtime_r(const time_t *timep, struct tm *tmp) 1577 { 1578 gmtcheck(); 1579 return gmtsub(NULL, timep, 0, tmp); 1580 } 1581 1582 struct tm * 1583 gmtime(const time_t *timep) 1584 { 1585 return gmtime_r(timep, &tm); 1586 } 1587 #ifdef STD_INSPIRED 1588 1589 struct tm * 1590 offtime(const time_t *timep, long offset) 1591 { 1592 gmtcheck(); 1593 return gmtsub(gmtptr, timep, (int_fast32_t)offset, &tm); 1594 } 1595 1596 struct tm * 1597 offtime_r(const time_t *timep, long offset, struct tm *tmp) 1598 { 1599 gmtcheck(); 1600 return gmtsub(NULL, timep, (int_fast32_t)offset, tmp); 1601 } 1602 1603 #endif /* defined STD_INSPIRED */ 1604 1605 /* 1606 ** Return the number of leap years through the end of the given year 1607 ** where, to make the math easy, the answer for year zero is defined as zero. 1608 */ 1609 1610 static int ATTRIBUTE_PURE 1611 leaps_thru_end_of(const int y) 1612 { 1613 return (y >= 0) ? (y / 4 - y / 100 + y / 400) : 1614 -(leaps_thru_end_of(-(y + 1)) + 1); 1615 } 1616 1617 static struct tm * 1618 timesub(const time_t *timep, int_fast32_t offset, 1619 const struct state *sp, struct tm *tmp) 1620 { 1621 const struct lsinfo * lp; 1622 time_t tdays; 1623 int idays; /* unsigned would be so 2003 */ 1624 int_fast64_t rem; 1625 int y; 1626 const int * ip; 1627 int_fast64_t corr; 1628 bool hit; 1629 int i; 1630 1631 corr = 0; 1632 hit = false; 1633 i = (sp == NULL) ? 0 : sp->leapcnt; 1634 while (--i >= 0) { 1635 lp = &sp->lsis[i]; 1636 if (*timep >= lp->ls_trans) { 1637 if (*timep == lp->ls_trans) { 1638 hit = ((i == 0 && lp->ls_corr > 0) || 1639 lp->ls_corr > sp->lsis[i - 1].ls_corr); 1640 if (hit) 1641 while (i > 0 && 1642 sp->lsis[i].ls_trans == 1643 sp->lsis[i - 1].ls_trans + 1 && 1644 sp->lsis[i].ls_corr == 1645 sp->lsis[i - 1].ls_corr + 1) { 1646 ++hit; 1647 --i; 1648 } 1649 } 1650 corr = lp->ls_corr; 1651 break; 1652 } 1653 } 1654 y = EPOCH_YEAR; 1655 tdays = (time_t)(*timep / SECSPERDAY); 1656 rem = *timep % SECSPERDAY; 1657 while (tdays < 0 || tdays >= year_lengths[isleap(y)]) { 1658 int newy; 1659 time_t tdelta; 1660 int idelta; 1661 int leapdays; 1662 1663 tdelta = tdays / DAYSPERLYEAR; 1664 if (! ((! TYPE_SIGNED(time_t) || INT_MIN <= tdelta) 1665 && tdelta <= INT_MAX)) 1666 goto out_of_range; 1667 _DIAGASSERT(__type_fit(int, tdelta)); 1668 idelta = (int)tdelta; 1669 if (idelta == 0) 1670 idelta = (tdays < 0) ? -1 : 1; 1671 newy = y; 1672 if (increment_overflow(&newy, idelta)) 1673 goto out_of_range; 1674 leapdays = leaps_thru_end_of(newy - 1) - 1675 leaps_thru_end_of(y - 1); 1676 tdays -= ((time_t) newy - y) * DAYSPERNYEAR; 1677 tdays -= leapdays; 1678 y = newy; 1679 } 1680 /* 1681 ** Given the range, we can now fearlessly cast... 1682 */ 1683 idays = (int) tdays; 1684 rem += offset - corr; 1685 while (rem < 0) { 1686 rem += SECSPERDAY; 1687 --idays; 1688 } 1689 while (rem >= SECSPERDAY) { 1690 rem -= SECSPERDAY; 1691 ++idays; 1692 } 1693 while (idays < 0) { 1694 if (increment_overflow(&y, -1)) 1695 goto out_of_range; 1696 idays += year_lengths[isleap(y)]; 1697 } 1698 while (idays >= year_lengths[isleap(y)]) { 1699 idays -= year_lengths[isleap(y)]; 1700 if (increment_overflow(&y, 1)) 1701 goto out_of_range; 1702 } 1703 tmp->tm_year = y; 1704 if (increment_overflow(&tmp->tm_year, -TM_YEAR_BASE)) 1705 goto out_of_range; 1706 tmp->tm_yday = idays; 1707 /* 1708 ** The "extra" mods below avoid overflow problems. 1709 */ 1710 tmp->tm_wday = EPOCH_WDAY + 1711 ((y - EPOCH_YEAR) % DAYSPERWEEK) * 1712 (DAYSPERNYEAR % DAYSPERWEEK) + 1713 leaps_thru_end_of(y - 1) - 1714 leaps_thru_end_of(EPOCH_YEAR - 1) + 1715 idays; 1716 tmp->tm_wday %= DAYSPERWEEK; 1717 if (tmp->tm_wday < 0) 1718 tmp->tm_wday += DAYSPERWEEK; 1719 tmp->tm_hour = (int) (rem / SECSPERHOUR); 1720 rem %= SECSPERHOUR; 1721 tmp->tm_min = (int) (rem / SECSPERMIN); 1722 /* 1723 ** A positive leap second requires a special 1724 ** representation. This uses "... ??:59:60" et seq. 1725 */ 1726 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit; 1727 ip = mon_lengths[isleap(y)]; 1728 for (tmp->tm_mon = 0; idays >= ip[tmp->tm_mon]; ++(tmp->tm_mon)) 1729 idays -= ip[tmp->tm_mon]; 1730 tmp->tm_mday = (int) (idays + 1); 1731 tmp->tm_isdst = 0; 1732 #ifdef TM_GMTOFF 1733 tmp->TM_GMTOFF = offset; 1734 #endif /* defined TM_GMTOFF */ 1735 return tmp; 1736 out_of_range: 1737 errno = EOVERFLOW; 1738 return NULL; 1739 } 1740 1741 char * 1742 ctime(const time_t *timep) 1743 { 1744 /* 1745 ** Section 4.12.3.2 of X3.159-1989 requires that 1746 ** The ctime function converts the calendar time pointed to by timer 1747 ** to local time in the form of a string. It is equivalent to 1748 ** asctime(localtime(timer)) 1749 */ 1750 struct tm *tmp = localtime(timep); 1751 return tmp ? asctime(tmp) : NULL; 1752 } 1753 1754 char * 1755 ctime_r(const time_t *timep, char *buf) 1756 { 1757 struct tm mytm; 1758 struct tm *tmp = localtime_r(timep, &mytm); 1759 return tmp ? asctime_r(tmp, buf) : NULL; 1760 } 1761 1762 char * 1763 ctime_rz(const timezone_t sp, const time_t * timep, char *buf) 1764 { 1765 struct tm mytm, *rtm; 1766 1767 rtm = localtime_rz(sp, timep, &mytm); 1768 if (rtm == NULL) 1769 return NULL; 1770 return asctime_r(rtm, buf); 1771 } 1772 1773 /* 1774 ** Adapted from code provided by Robert Elz, who writes: 1775 ** The "best" way to do mktime I think is based on an idea of Bob 1776 ** Kridle's (so its said...) from a long time ago. 1777 ** It does a binary search of the time_t space. Since time_t's are 1778 ** just 32 bits, its a max of 32 iterations (even at 64 bits it 1779 ** would still be very reasonable). 1780 */ 1781 1782 #ifndef WRONG 1783 #define WRONG ((time_t)-1) 1784 #endif /* !defined WRONG */ 1785 1786 /* 1787 ** Normalize logic courtesy Paul Eggert. 1788 */ 1789 1790 static bool 1791 increment_overflow(int *ip, int j) 1792 { 1793 int const i = *ip; 1794 1795 /* 1796 ** If i >= 0 there can only be overflow if i + j > INT_MAX 1797 ** or if j > INT_MAX - i; given i >= 0, INT_MAX - i cannot overflow. 1798 ** If i < 0 there can only be overflow if i + j < INT_MIN 1799 ** or if j < INT_MIN - i; given i < 0, INT_MIN - i cannot overflow. 1800 */ 1801 if ((i >= 0) ? (j > INT_MAX - i) : (j < INT_MIN - i)) 1802 return true; 1803 *ip += j; 1804 return false; 1805 } 1806 1807 static bool 1808 increment_overflow32(int_fast32_t *const lp, int const m) 1809 { 1810 int_fast32_t const l = *lp; 1811 1812 if ((l >= 0) ? (m > INT_FAST32_MAX - l) : (m < INT_FAST32_MIN - l)) 1813 return true; 1814 *lp += m; 1815 return false; 1816 } 1817 1818 static bool 1819 increment_overflow_time(time_t *tp, int_fast32_t j) 1820 { 1821 /* 1822 ** This is like 1823 ** 'if (! (time_t_min <= *tp + j && *tp + j <= time_t_max)) ...', 1824 ** except that it does the right thing even if *tp + j would overflow. 1825 */ 1826 if (! (j < 0 1827 ? (TYPE_SIGNED(time_t) ? time_t_min - j <= *tp : -1 - j < *tp) 1828 : *tp <= time_t_max - j)) 1829 return true; 1830 *tp += j; 1831 return false; 1832 } 1833 1834 static bool 1835 normalize_overflow(int *const tensptr, int *const unitsptr, const int base) 1836 { 1837 int tensdelta; 1838 1839 tensdelta = (*unitsptr >= 0) ? 1840 (*unitsptr / base) : 1841 (-1 - (-1 - *unitsptr) / base); 1842 *unitsptr -= tensdelta * base; 1843 return increment_overflow(tensptr, tensdelta); 1844 } 1845 1846 static bool 1847 normalize_overflow32(int_fast32_t *tensptr, int *unitsptr, int base) 1848 { 1849 int tensdelta; 1850 1851 tensdelta = (*unitsptr >= 0) ? 1852 (*unitsptr / base) : 1853 (-1 - (-1 - *unitsptr) / base); 1854 *unitsptr -= tensdelta * base; 1855 return increment_overflow32(tensptr, tensdelta); 1856 } 1857 1858 static int 1859 tmcomp(const struct tm *const atmp, 1860 const struct tm *const btmp) 1861 { 1862 int result; 1863 1864 if (atmp->tm_year != btmp->tm_year) 1865 return atmp->tm_year < btmp->tm_year ? -1 : 1; 1866 if ((result = (atmp->tm_mon - btmp->tm_mon)) == 0 && 1867 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && 1868 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && 1869 (result = (atmp->tm_min - btmp->tm_min)) == 0) 1870 result = atmp->tm_sec - btmp->tm_sec; 1871 return result; 1872 } 1873 1874 static time_t 1875 time2sub(struct tm *const tmp, 1876 struct tm *(*funcp)(struct state const *, time_t const *, 1877 int_fast32_t, struct tm *), 1878 struct state const *sp, 1879 const int_fast32_t offset, 1880 bool *okayp, 1881 bool do_norm_secs) 1882 { 1883 int dir; 1884 int i, j; 1885 int saved_seconds; 1886 int_fast32_t li; 1887 time_t lo; 1888 time_t hi; 1889 #ifdef NO_ERROR_IN_DST_GAP 1890 time_t ilo; 1891 #endif 1892 int_fast32_t y; 1893 time_t newt; 1894 time_t t; 1895 struct tm yourtm, mytm; 1896 1897 *okayp = false; 1898 yourtm = *tmp; 1899 #ifdef NO_ERROR_IN_DST_GAP 1900 again: 1901 #endif 1902 if (do_norm_secs) { 1903 if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec, 1904 SECSPERMIN)) 1905 goto out_of_range; 1906 } 1907 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) 1908 goto out_of_range; 1909 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) 1910 goto out_of_range; 1911 y = yourtm.tm_year; 1912 if (normalize_overflow32(&y, &yourtm.tm_mon, MONSPERYEAR)) 1913 goto out_of_range; 1914 /* 1915 ** Turn y into an actual year number for now. 1916 ** It is converted back to an offset from TM_YEAR_BASE later. 1917 */ 1918 if (increment_overflow32(&y, TM_YEAR_BASE)) 1919 goto out_of_range; 1920 while (yourtm.tm_mday <= 0) { 1921 if (increment_overflow32(&y, -1)) 1922 goto out_of_range; 1923 li = y + (1 < yourtm.tm_mon); 1924 yourtm.tm_mday += year_lengths[isleap(li)]; 1925 } 1926 while (yourtm.tm_mday > DAYSPERLYEAR) { 1927 li = y + (1 < yourtm.tm_mon); 1928 yourtm.tm_mday -= year_lengths[isleap(li)]; 1929 if (increment_overflow32(&y, 1)) 1930 goto out_of_range; 1931 } 1932 for ( ; ; ) { 1933 i = mon_lengths[isleap(y)][yourtm.tm_mon]; 1934 if (yourtm.tm_mday <= i) 1935 break; 1936 yourtm.tm_mday -= i; 1937 if (++yourtm.tm_mon >= MONSPERYEAR) { 1938 yourtm.tm_mon = 0; 1939 if (increment_overflow32(&y, 1)) 1940 goto out_of_range; 1941 } 1942 } 1943 if (increment_overflow32(&y, -TM_YEAR_BASE)) 1944 goto out_of_range; 1945 if (! (INT_MIN <= y && y <= INT_MAX)) 1946 goto out_of_range; 1947 yourtm.tm_year = (int)y; 1948 if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN) 1949 saved_seconds = 0; 1950 else if (y + TM_YEAR_BASE < EPOCH_YEAR) { 1951 /* 1952 ** We can't set tm_sec to 0, because that might push the 1953 ** time below the minimum representable time. 1954 ** Set tm_sec to 59 instead. 1955 ** This assumes that the minimum representable time is 1956 ** not in the same minute that a leap second was deleted from, 1957 ** which is a safer assumption than using 58 would be. 1958 */ 1959 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) 1960 goto out_of_range; 1961 saved_seconds = yourtm.tm_sec; 1962 yourtm.tm_sec = SECSPERMIN - 1; 1963 } else { 1964 saved_seconds = yourtm.tm_sec; 1965 yourtm.tm_sec = 0; 1966 } 1967 /* 1968 ** Do a binary search (this works whatever time_t's type is). 1969 */ 1970 lo = time_t_min; 1971 hi = time_t_max; 1972 #ifdef NO_ERROR_IN_DST_GAP 1973 ilo = lo; 1974 #endif 1975 for ( ; ; ) { 1976 t = lo / 2 + hi / 2; 1977 if (t < lo) 1978 t = lo; 1979 else if (t > hi) 1980 t = hi; 1981 if (! funcp(sp, &t, offset, &mytm)) { 1982 /* 1983 ** Assume that t is too extreme to be represented in 1984 ** a struct tm; arrange things so that it is less 1985 ** extreme on the next pass. 1986 */ 1987 dir = (t > 0) ? 1 : -1; 1988 } else dir = tmcomp(&mytm, &yourtm); 1989 if (dir != 0) { 1990 if (t == lo) { 1991 if (t == time_t_max) 1992 goto out_of_range; 1993 ++t; 1994 ++lo; 1995 } else if (t == hi) { 1996 if (t == time_t_min) 1997 goto out_of_range; 1998 --t; 1999 --hi; 2000 } 2001 #ifdef NO_ERROR_IN_DST_GAP 2002 if (ilo != lo && lo - 1 == hi && yourtm.tm_isdst < 0 && 2003 do_norm_secs) { 2004 for (i = sp->typecnt - 1; i >= 0; --i) { 2005 for (j = sp->typecnt - 1; j >= 0; --j) { 2006 time_t off; 2007 if (sp->ttis[j].tt_isdst == 2008 sp->ttis[i].tt_isdst) 2009 continue; 2010 off = sp->ttis[j].tt_gmtoff - 2011 sp->ttis[i].tt_gmtoff; 2012 yourtm.tm_sec += off < 0 ? 2013 -off : off; 2014 goto again; 2015 } 2016 } 2017 } 2018 #endif 2019 if (lo > hi) 2020 goto invalid; 2021 if (dir > 0) 2022 hi = t; 2023 else lo = t; 2024 continue; 2025 } 2026 #if defined TM_GMTOFF && ! UNINIT_TRAP 2027 if (mytm.TM_GMTOFF != yourtm.TM_GMTOFF 2028 && (yourtm.TM_GMTOFF < 0 2029 ? (-SECSPERDAY <= yourtm.TM_GMTOFF 2030 && (mytm.TM_GMTOFF <= 2031 (/*CONSTCOND*/SMALLEST (INT_FAST32_MAX, LONG_MAX) 2032 + yourtm.TM_GMTOFF))) 2033 : (yourtm.TM_GMTOFF <= SECSPERDAY 2034 && ((/*CONSTCOND*/BIGGEST (INT_FAST32_MIN, LONG_MIN) 2035 + yourtm.TM_GMTOFF) 2036 <= mytm.TM_GMTOFF)))) { 2037 /* MYTM matches YOURTM except with the wrong UTC offset. 2038 YOURTM.TM_GMTOFF is plausible, so try it instead. 2039 It's OK if YOURTM.TM_GMTOFF contains uninitialized data, 2040 since the guess gets checked. */ 2041 time_t altt = t; 2042 int_fast32_t diff = (int_fast32_t) 2043 (mytm.TM_GMTOFF - yourtm.TM_GMTOFF); 2044 if (!increment_overflow_time(&altt, diff)) { 2045 struct tm alttm; 2046 if (! funcp(sp, &altt, offset, &alttm) 2047 && alttm.tm_isdst == mytm.tm_isdst 2048 && alttm.TM_GMTOFF == yourtm.TM_GMTOFF 2049 && tmcomp(&alttm, &yourtm)) { 2050 t = altt; 2051 mytm = alttm; 2052 } 2053 } 2054 } 2055 #endif 2056 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) 2057 break; 2058 /* 2059 ** Right time, wrong type. 2060 ** Hunt for right time, right type. 2061 ** It's okay to guess wrong since the guess 2062 ** gets checked. 2063 */ 2064 if (sp == NULL) 2065 goto invalid; 2066 for (i = sp->typecnt - 1; i >= 0; --i) { 2067 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) 2068 continue; 2069 for (j = sp->typecnt - 1; j >= 0; --j) { 2070 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) 2071 continue; 2072 newt = (time_t)(t + sp->ttis[j].tt_gmtoff - 2073 sp->ttis[i].tt_gmtoff); 2074 if (! funcp(sp, &newt, offset, &mytm)) 2075 continue; 2076 if (tmcomp(&mytm, &yourtm) != 0) 2077 continue; 2078 if (mytm.tm_isdst != yourtm.tm_isdst) 2079 continue; 2080 /* 2081 ** We have a match. 2082 */ 2083 t = newt; 2084 goto label; 2085 } 2086 } 2087 goto invalid; 2088 } 2089 label: 2090 newt = t + saved_seconds; 2091 if ((newt < t) != (saved_seconds < 0)) 2092 goto out_of_range; 2093 t = newt; 2094 if (funcp(sp, &t, offset, tmp)) { 2095 *okayp = true; 2096 return t; 2097 } 2098 out_of_range: 2099 errno = EOVERFLOW; 2100 return WRONG; 2101 invalid: 2102 errno = EINVAL; 2103 return WRONG; 2104 } 2105 2106 static time_t 2107 time2(struct tm * const tmp, 2108 struct tm *(*funcp)(struct state const *, time_t const *, 2109 int_fast32_t, struct tm *), 2110 struct state const *sp, 2111 const int_fast32_t offset, 2112 bool *okayp) 2113 { 2114 time_t t; 2115 2116 /* 2117 ** First try without normalization of seconds 2118 ** (in case tm_sec contains a value associated with a leap second). 2119 ** If that fails, try with normalization of seconds. 2120 */ 2121 t = time2sub(tmp, funcp, sp, offset, okayp, false); 2122 return *okayp ? t : time2sub(tmp, funcp, sp, offset, okayp, true); 2123 } 2124 2125 static time_t 2126 time1(struct tm *const tmp, 2127 struct tm *(*funcp) (struct state const *, time_t const *, 2128 int_fast32_t, struct tm *), 2129 struct state const *sp, 2130 const int_fast32_t offset) 2131 { 2132 time_t t; 2133 int samei, otheri; 2134 int sameind, otherind; 2135 int i; 2136 int nseen; 2137 int save_errno; 2138 char seen[TZ_MAX_TYPES]; 2139 unsigned char types[TZ_MAX_TYPES]; 2140 bool okay; 2141 2142 if (tmp == NULL) { 2143 errno = EINVAL; 2144 return WRONG; 2145 } 2146 if (tmp->tm_isdst > 1) 2147 tmp->tm_isdst = 1; 2148 save_errno = errno; 2149 t = time2(tmp, funcp, sp, offset, &okay); 2150 if (okay) { 2151 errno = save_errno; 2152 return t; 2153 } 2154 if (tmp->tm_isdst < 0) 2155 #ifdef PCTS 2156 /* 2157 ** POSIX Conformance Test Suite code courtesy Grant Sullivan. 2158 */ 2159 tmp->tm_isdst = 0; /* reset to std and try again */ 2160 #else 2161 return t; 2162 #endif /* !defined PCTS */ 2163 /* 2164 ** We're supposed to assume that somebody took a time of one type 2165 ** and did some math on it that yielded a "struct tm" that's bad. 2166 ** We try to divine the type they started from and adjust to the 2167 ** type they need. 2168 */ 2169 if (sp == NULL) { 2170 errno = EINVAL; 2171 return WRONG; 2172 } 2173 for (i = 0; i < sp->typecnt; ++i) 2174 seen[i] = false; 2175 nseen = 0; 2176 for (i = sp->timecnt - 1; i >= 0; --i) 2177 if (!seen[sp->types[i]]) { 2178 seen[sp->types[i]] = true; 2179 types[nseen++] = sp->types[i]; 2180 } 2181 for (sameind = 0; sameind < nseen; ++sameind) { 2182 samei = types[sameind]; 2183 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) 2184 continue; 2185 for (otherind = 0; otherind < nseen; ++otherind) { 2186 otheri = types[otherind]; 2187 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) 2188 continue; 2189 tmp->tm_sec += (int)(sp->ttis[otheri].tt_gmtoff - 2190 sp->ttis[samei].tt_gmtoff); 2191 tmp->tm_isdst = !tmp->tm_isdst; 2192 t = time2(tmp, funcp, sp, offset, &okay); 2193 if (okay) { 2194 errno = save_errno; 2195 return t; 2196 } 2197 tmp->tm_sec -= (int)(sp->ttis[otheri].tt_gmtoff - 2198 sp->ttis[samei].tt_gmtoff); 2199 tmp->tm_isdst = !tmp->tm_isdst; 2200 } 2201 } 2202 errno = EOVERFLOW; 2203 return WRONG; 2204 } 2205 2206 static time_t 2207 mktime_tzname(timezone_t sp, struct tm *tmp, bool setname) 2208 { 2209 if (sp) 2210 return time1(tmp, localsub, sp, setname); 2211 else { 2212 gmtcheck(); 2213 return time1(tmp, gmtsub, gmtptr, 0); 2214 } 2215 } 2216 2217 #if NETBSD_INSPIRED 2218 2219 time_t 2220 mktime_z(timezone_t sp, struct tm *const tmp) 2221 { 2222 return mktime_tzname(sp, tmp, false); 2223 } 2224 2225 #endif 2226 2227 time_t 2228 mktime(struct tm *tmp) 2229 { 2230 time_t t; 2231 2232 rwlock_wrlock(&lcl_lock); 2233 tzset_unlocked(); 2234 t = mktime_tzname(lclptr, tmp, true); 2235 rwlock_unlock(&lcl_lock); 2236 return t; 2237 } 2238 2239 #ifdef STD_INSPIRED 2240 2241 time_t 2242 timelocal_z(const timezone_t sp, struct tm *const tmp) 2243 { 2244 if (tmp != NULL) 2245 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 2246 return mktime_z(sp, tmp); 2247 } 2248 2249 time_t 2250 timelocal(struct tm *tmp) 2251 { 2252 if (tmp != NULL) 2253 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 2254 return mktime(tmp); 2255 } 2256 2257 time_t 2258 timegm(struct tm *tmp) 2259 { 2260 2261 return timeoff(tmp, 0); 2262 } 2263 2264 time_t 2265 timeoff(struct tm *tmp, long offset) 2266 { 2267 if (tmp) 2268 tmp->tm_isdst = 0; 2269 gmtcheck(); 2270 return time1(tmp, gmtsub, gmtptr, (int_fast32_t)offset); 2271 } 2272 2273 #endif /* defined STD_INSPIRED */ 2274 2275 /* 2276 ** XXX--is the below the right way to conditionalize?? 2277 */ 2278 2279 #ifdef STD_INSPIRED 2280 2281 /* 2282 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 2283 ** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which 2284 ** is not the case if we are accounting for leap seconds. 2285 ** So, we provide the following conversion routines for use 2286 ** when exchanging timestamps with POSIX conforming systems. 2287 */ 2288 2289 static int_fast64_t 2290 leapcorr(const timezone_t sp, time_t t) 2291 { 2292 struct lsinfo const * lp; 2293 int i; 2294 2295 i = sp->leapcnt; 2296 while (--i >= 0) { 2297 lp = &sp->lsis[i]; 2298 if (t >= lp->ls_trans) 2299 return lp->ls_corr; 2300 } 2301 return 0; 2302 } 2303 2304 NETBSD_INSPIRED_EXTERN time_t ATTRIBUTE_PURE 2305 time2posix_z(timezone_t sp, time_t t) 2306 { 2307 return (time_t)(t - leapcorr(sp, t)); 2308 } 2309 2310 time_t 2311 time2posix(time_t t) 2312 { 2313 rwlock_wrlock(&lcl_lock); 2314 if (!lcl_is_set) 2315 tzset_unlocked(); 2316 if (lclptr) 2317 t = (time_t)(t - leapcorr(lclptr, t)); 2318 rwlock_unlock(&lcl_lock); 2319 return t; 2320 } 2321 2322 NETBSD_INSPIRED_EXTERN time_t ATTRIBUTE_PURE 2323 posix2time_z(timezone_t sp, time_t t) 2324 { 2325 time_t x; 2326 time_t y; 2327 2328 /* 2329 ** For a positive leap second hit, the result 2330 ** is not unique. For a negative leap second 2331 ** hit, the corresponding time doesn't exist, 2332 ** so we return an adjacent second. 2333 */ 2334 x = (time_t)(t + leapcorr(sp, t)); 2335 y = (time_t)(x - leapcorr(sp, x)); 2336 if (y < t) { 2337 do { 2338 x++; 2339 y = (time_t)(x - leapcorr(sp, x)); 2340 } while (y < t); 2341 x -= y != t; 2342 } else if (y > t) { 2343 do { 2344 --x; 2345 y = (time_t)(x - leapcorr(sp, x)); 2346 } while (y > t); 2347 x += y != t; 2348 } 2349 return x; 2350 } 2351 2352 time_t 2353 posix2time(time_t t) 2354 { 2355 rwlock_wrlock(&lcl_lock); 2356 if (!lcl_is_set) 2357 tzset_unlocked(); 2358 if (lclptr) 2359 t = posix2time_z(lclptr, t); 2360 rwlock_unlock(&lcl_lock); 2361 return t; 2362 } 2363 2364 #endif /* defined STD_INSPIRED */ 2365