1 /* $NetBSD: localtime.c,v 1.77 2013/07/30 15:30:37 joerg 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 1.77 2013/07/30 15:30:37 joerg 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 "private.h" 26 #include "tzfile.h" 27 #include "fcntl.h" 28 #include "reentrant.h" 29 30 #if defined(__weak_alias) 31 __weak_alias(daylight,_daylight) 32 __weak_alias(tzname,_tzname) 33 #endif 34 35 #include "float.h" /* for FLT_MAX and DBL_MAX */ 36 37 #ifndef TZ_ABBR_MAX_LEN 38 #define TZ_ABBR_MAX_LEN 16 39 #endif /* !defined TZ_ABBR_MAX_LEN */ 40 41 #ifndef TZ_ABBR_CHAR_SET 42 #define TZ_ABBR_CHAR_SET \ 43 "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 :+-._" 44 #endif /* !defined TZ_ABBR_CHAR_SET */ 45 46 #ifndef TZ_ABBR_ERR_CHAR 47 #define TZ_ABBR_ERR_CHAR '_' 48 #endif /* !defined TZ_ABBR_ERR_CHAR */ 49 50 /* 51 ** SunOS 4.1.1 headers lack O_BINARY. 52 */ 53 54 #ifdef O_BINARY 55 #define OPEN_MODE (O_RDONLY | O_BINARY) 56 #endif /* defined O_BINARY */ 57 #ifndef O_BINARY 58 #define OPEN_MODE O_RDONLY 59 #endif /* !defined O_BINARY */ 60 61 #ifndef WILDABBR 62 /* 63 ** Someone might make incorrect use of a time zone abbreviation: 64 ** 1. They might reference tzname[0] before calling tzset (explicitly 65 ** or implicitly). 66 ** 2. They might reference tzname[1] before calling tzset (explicitly 67 ** or implicitly). 68 ** 3. They might reference tzname[1] after setting to a time zone 69 ** in which Daylight Saving Time is never observed. 70 ** 4. They might reference tzname[0] after setting to a time zone 71 ** in which Standard Time is never observed. 72 ** 5. They might reference tm.TM_ZONE after calling offtime. 73 ** What's best to do in the above cases is open to debate; 74 ** for now, we just set things up so that in any of the five cases 75 ** WILDABBR is used. Another possibility: initialize tzname[0] to the 76 ** string "tzname[0] used before set", and similarly for the other cases. 77 ** And another: initialize tzname[0] to "ERA", with an explanation in the 78 ** manual page of what this "time zone abbreviation" means (doing this so 79 ** that tzname[0] has the "normal" length of three characters). 80 */ 81 #define WILDABBR " " 82 #endif /* !defined WILDABBR */ 83 84 static const char wildabbr[] = WILDABBR; 85 86 static const char gmt[] = "GMT"; 87 88 /* 89 ** The DST rules to use if TZ has no rules and we can't load TZDEFRULES. 90 ** We default to US rules as of 1999-08-17. 91 ** POSIX 1003.1 section 8.1.1 says that the default DST rules are 92 ** implementation dependent; for historical reasons, US rules are a 93 ** common default. 94 */ 95 #ifndef TZDEFRULESTRING 96 #define TZDEFRULESTRING ",M4.1.0,M10.5.0" 97 #endif /* !defined TZDEFDST */ 98 99 struct ttinfo { /* time type information */ 100 int_fast32_t tt_gmtoff; /* UTC offset in seconds */ 101 int tt_isdst; /* used to set tm_isdst */ 102 int tt_abbrind; /* abbreviation list index */ 103 int tt_ttisstd; /* TRUE if transition is std time */ 104 int tt_ttisgmt; /* TRUE if transition is UTC */ 105 }; 106 107 struct lsinfo { /* leap second information */ 108 time_t ls_trans; /* transition time */ 109 int_fast64_t ls_corr; /* correction to apply */ 110 }; 111 112 #define BIGGEST(a, b) (((a) > (b)) ? (a) : (b)) 113 114 #ifdef TZNAME_MAX 115 #define MY_TZNAME_MAX TZNAME_MAX 116 #endif /* defined TZNAME_MAX */ 117 #ifndef TZNAME_MAX 118 #define MY_TZNAME_MAX 255 119 #endif /* !defined TZNAME_MAX */ 120 121 struct __state { 122 int leapcnt; 123 int timecnt; 124 int typecnt; 125 int charcnt; 126 int goback; 127 int goahead; 128 time_t ats[TZ_MAX_TIMES]; 129 unsigned char types[TZ_MAX_TIMES]; 130 struct ttinfo ttis[TZ_MAX_TYPES]; 131 char chars[/*CONSTCOND*/BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, 132 sizeof gmt), (2 * (MY_TZNAME_MAX + 1)))]; 133 struct lsinfo lsis[TZ_MAX_LEAPS]; 134 int defaulttype; /* for early times or if no transitions */ 135 }; 136 137 struct rule { 138 int r_type; /* type of rule--see below */ 139 int r_day; /* day number of rule */ 140 int r_week; /* week number of rule */ 141 int r_mon; /* month number of rule */ 142 int_fast32_t r_time; /* transition time of rule */ 143 }; 144 145 #define JULIAN_DAY 0 /* Jn - Julian day */ 146 #define DAY_OF_YEAR 1 /* n - day of year */ 147 #define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */ 148 149 typedef struct tm *(*subfun_t)(const timezone_t sp, const time_t *timep, 150 const int_fast32_t offset, struct tm *tmp); 151 152 /* 153 ** Prototypes for static functions. 154 */ 155 156 static int_fast32_t detzcode(const char * codep); 157 static time_t detzcode64(const char * codep); 158 static int differ_by_repeat(time_t t1, time_t t0); 159 static const char * getzname(const char * strp) ATTRIBUTE_PURE; 160 static const char * getqzname(const char * strp, const int delim) ATTRIBUTE_PURE; 161 static const char * getnum(const char * strp, int * nump, int min, 162 int max); 163 static const char * getsecs(const char * strp, int_fast32_t * secsp); 164 static const char * getoffset(const char * strp, int_fast32_t * offsetp); 165 static const char * getrule(const char * strp, struct rule * rulep); 166 static void gmtload(timezone_t sp); 167 static struct tm * gmtsub(const timezone_t sp, const time_t *timep, 168 const int_fast32_t offset, struct tm * tmp); 169 static struct tm * localsub(const timezone_t sp, const time_t *timep, 170 const int_fast32_t offset, struct tm *tmp); 171 static int increment_overflow(int * number, int delta); 172 static int increment_overflow32(int_fast32_t * number, int delta); 173 static int leaps_thru_end_of(int y) ATTRIBUTE_PURE; 174 static int normalize_overflow(int * tensptr, int * unitsptr, 175 int base); 176 static int normalize_overflow32(int_fast32_t * tensptr, 177 int * unitsptr, int base); 178 static void settzname(void); 179 static time_t time1(const timezone_t sp, struct tm * const tmp, 180 subfun_t funcp, const int_fast32_t offset); 181 static time_t time2(const timezone_t sp, struct tm * const tmp, 182 subfun_t funcp, 183 const int_fast32_t offset, int *const okayp); 184 static time_t time2sub(const timezone_t sp, struct tm * const tmp, 185 subfun_t funcp, const int_fast32_t offset, 186 int *const okayp, const int do_norm_secs); 187 static struct tm * timesub(const timezone_t sp, const time_t * timep, 188 const int_fast32_t offset, struct tm * tmp); 189 static int tmcomp(const struct tm * atmp, 190 const struct tm * btmp); 191 static time_t transtime(time_t janfirst, int year, 192 const struct rule * rulep, 193 const int_fast32_t offset) ATTRIBUTE_PURE; 194 static int typesequiv(const timezone_t sp, int a, int b); 195 static int tzload(timezone_t sp, const char * name, 196 int doextend); 197 static int tzparse(timezone_t sp, const char * name, 198 int lastditch); 199 static void tzset_unlocked(void); 200 static void tzsetwall_unlocked(void); 201 static int_fast64_t leapcorr(const timezone_t sp, time_t * timep); 202 203 static timezone_t lclptr; 204 static timezone_t gmtptr; 205 206 #ifndef TZ_STRLEN_MAX 207 #define TZ_STRLEN_MAX 255 208 #endif /* !defined TZ_STRLEN_MAX */ 209 210 static char lcl_TZname[TZ_STRLEN_MAX + 1]; 211 static int lcl_is_set; 212 static int gmt_is_set; 213 214 #if !defined(__LIBC12_SOURCE__) 215 216 __aconst char * tzname[2] = { 217 (__aconst char *)__UNCONST(wildabbr), 218 (__aconst char *)__UNCONST(wildabbr) 219 }; 220 221 #else 222 223 extern __aconst char * tzname[2]; 224 225 #endif 226 227 #ifdef _REENTRANT 228 static rwlock_t lcl_lock = RWLOCK_INITIALIZER; 229 #endif 230 231 /* 232 ** Section 4.12.3 of X3.159-1989 requires that 233 ** Except for the strftime function, these functions [asctime, 234 ** ctime, gmtime, localtime] return values in one of two static 235 ** objects: a broken-down time structure and an array of char. 236 ** Thanks to Paul Eggert for noting this. 237 */ 238 239 static struct tm tm; 240 241 #ifdef USG_COMPAT 242 #if !defined(__LIBC12_SOURCE__) 243 long timezone = 0; 244 int daylight = 0; 245 #else 246 extern int daylight; 247 extern long timezone __RENAME(__timezone13); 248 #endif 249 #endif /* defined USG_COMPAT */ 250 251 #ifdef ALTZONE 252 time_t altzone = 0; 253 #endif /* defined ALTZONE */ 254 255 static int_fast32_t 256 detzcode(const char *const codep) 257 { 258 int_fast32_t result; 259 int i; 260 261 result = (codep[0] & 0x80) ? -1 : 0; 262 for (i = 0; i < 4; ++i) 263 result = (result << 8) | (codep[i] & 0xff); 264 return result; 265 } 266 267 static time_t 268 detzcode64(const char *const codep) 269 { 270 time_t result; 271 int i; 272 273 result = (time_t)((codep[0] & 0x80) ? (~(int_fast64_t) 0) : 0); 274 for (i = 0; i < 8; ++i) 275 result = result * 256 + (codep[i] & 0xff); 276 return result; 277 } 278 279 const char * 280 tzgetname(const timezone_t sp, int isdst) 281 { 282 int i; 283 for (i = 0; i < sp->timecnt; ++i) { 284 const struct ttinfo *const ttisp = &sp->ttis[sp->types[i]]; 285 286 if (ttisp->tt_isdst == isdst) 287 return &sp->chars[ttisp->tt_abbrind]; 288 } 289 return NULL; 290 } 291 292 static void 293 settzname_z(timezone_t sp) 294 { 295 int i; 296 297 /* 298 ** Scrub the abbreviations. 299 ** First, replace bogus characters. 300 */ 301 for (i = 0; i < sp->charcnt; ++i) 302 if (strchr(TZ_ABBR_CHAR_SET, sp->chars[i]) == NULL) 303 sp->chars[i] = TZ_ABBR_ERR_CHAR; 304 /* 305 ** Second, truncate long abbreviations. 306 */ 307 for (i = 0; i < sp->typecnt; ++i) { 308 const struct ttinfo * const ttisp = &sp->ttis[i]; 309 char * cp = &sp->chars[ttisp->tt_abbrind]; 310 311 if (strlen(cp) > TZ_ABBR_MAX_LEN && 312 strcmp(cp, GRANDPARENTED) != 0) 313 *(cp + TZ_ABBR_MAX_LEN) = '\0'; 314 } 315 } 316 317 static void 318 settzname(void) 319 { 320 timezone_t const sp = lclptr; 321 int i; 322 323 tzname[0] = (__aconst char *)__UNCONST(wildabbr); 324 tzname[1] = (__aconst char *)__UNCONST(wildabbr); 325 #ifdef USG_COMPAT 326 daylight = 0; 327 timezone = 0; 328 #endif /* defined USG_COMPAT */ 329 #ifdef ALTZONE 330 altzone = 0; 331 #endif /* defined ALTZONE */ 332 if (sp == NULL) { 333 tzname[0] = tzname[1] = (__aconst char *)__UNCONST(gmt); 334 return; 335 } 336 /* 337 ** And to get the latest zone names into tzname. . . 338 */ 339 for (i = 0; i < sp->typecnt; ++i) { 340 const struct ttinfo * const ttisp = &sp->ttis[i]; 341 342 tzname[ttisp->tt_isdst] = &sp->chars[ttisp->tt_abbrind]; 343 #ifdef USG_COMPAT 344 if (ttisp->tt_isdst) 345 daylight = 1; 346 if (!ttisp->tt_isdst) 347 timezone = -(ttisp->tt_gmtoff); 348 #endif /* defined USG_COMPAT */ 349 #ifdef ALTZONE 350 if (ttisp->tt_isdst) 351 altzone = -(ttisp->tt_gmtoff); 352 #endif /* defined ALTZONE */ 353 } 354 settzname_z(sp); 355 } 356 357 static int 358 differ_by_repeat(const time_t t1, const time_t t0) 359 { 360 if (TYPE_INTEGRAL(time_t) && 361 TYPE_BIT(time_t) - TYPE_SIGNED(time_t) < SECSPERREPEAT_BITS) 362 return 0; 363 return (int_fast64_t)t1 - (int_fast64_t)t0 == SECSPERREPEAT; 364 } 365 366 static int 367 tzload(timezone_t sp, const char *name, const int doextend) 368 { 369 const char * p; 370 int i; 371 int fid; 372 int stored; 373 ssize_t nread; 374 typedef union { 375 struct tzhead tzhead; 376 char buf[2 * sizeof(struct tzhead) + 377 2 * sizeof *sp + 378 4 * TZ_MAX_TIMES]; 379 } u_t; 380 u_t * up; 381 382 up = calloc(1, sizeof *up); 383 if (up == NULL) 384 return -1; 385 386 sp->goback = sp->goahead = FALSE; 387 if (name == NULL && (name = TZDEFAULT) == NULL) 388 goto oops; 389 { 390 int doaccess; 391 /* 392 ** Section 4.9.1 of the C standard says that 393 ** "FILENAME_MAX expands to an integral constant expression 394 ** that is the size needed for an array of char large enough 395 ** to hold the longest file name string that the implementation 396 ** guarantees can be opened." 397 */ 398 char fullname[FILENAME_MAX + 1]; 399 400 if (name[0] == ':') 401 ++name; 402 doaccess = name[0] == '/'; 403 if (!doaccess) { 404 if ((p = TZDIR) == NULL) 405 goto oops; 406 if ((strlen(p) + strlen(name) + 1) >= sizeof fullname) 407 goto oops; 408 (void) strcpy(fullname, p); /* XXX strcpy is safe */ 409 (void) strcat(fullname, "/"); /* XXX strcat is safe */ 410 (void) strcat(fullname, name); /* XXX strcat is safe */ 411 /* 412 ** Set doaccess if '.' (as in "../") shows up in name. 413 */ 414 if (strchr(name, '.') != NULL) 415 doaccess = TRUE; 416 name = fullname; 417 } 418 if (doaccess && access(name, R_OK) != 0) 419 goto oops; 420 /* 421 * XXX potential security problem here if user of a set-id 422 * program has set TZ (which is passed in as name) here, 423 * and uses a race condition trick to defeat the access(2) 424 * above. 425 */ 426 if ((fid = open(name, OPEN_MODE)) == -1) 427 goto oops; 428 } 429 nread = read(fid, up->buf, sizeof up->buf); 430 if (close(fid) < 0 || nread <= 0) 431 goto oops; 432 for (stored = 4; stored <= 8; stored *= 2) { 433 int ttisstdcnt; 434 int ttisgmtcnt; 435 436 ttisstdcnt = (int) detzcode(up->tzhead.tzh_ttisstdcnt); 437 ttisgmtcnt = (int) detzcode(up->tzhead.tzh_ttisgmtcnt); 438 sp->leapcnt = (int) detzcode(up->tzhead.tzh_leapcnt); 439 sp->timecnt = (int) detzcode(up->tzhead.tzh_timecnt); 440 sp->typecnt = (int) detzcode(up->tzhead.tzh_typecnt); 441 sp->charcnt = (int) detzcode(up->tzhead.tzh_charcnt); 442 p = up->tzhead.tzh_charcnt + sizeof up->tzhead.tzh_charcnt; 443 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS || 444 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES || 445 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES || 446 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS || 447 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) || 448 (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0)) 449 goto oops; 450 if (nread - (p - up->buf) < 451 sp->timecnt * stored + /* ats */ 452 sp->timecnt + /* types */ 453 sp->typecnt * 6 + /* ttinfos */ 454 sp->charcnt + /* chars */ 455 sp->leapcnt * (stored + 4) + /* lsinfos */ 456 ttisstdcnt + /* ttisstds */ 457 ttisgmtcnt) /* ttisgmts */ 458 goto oops; 459 for (i = 0; i < sp->timecnt; ++i) { 460 sp->ats[i] = (time_t)((stored == 4) ? 461 detzcode(p) : detzcode64(p)); 462 p += stored; 463 } 464 for (i = 0; i < sp->timecnt; ++i) { 465 sp->types[i] = (unsigned char) *p++; 466 if (sp->types[i] >= sp->typecnt) 467 goto oops; 468 } 469 for (i = 0; i < sp->typecnt; ++i) { 470 struct ttinfo * ttisp; 471 472 ttisp = &sp->ttis[i]; 473 ttisp->tt_gmtoff = detzcode(p); 474 p += 4; 475 ttisp->tt_isdst = (unsigned char) *p++; 476 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1) 477 goto oops; 478 ttisp->tt_abbrind = (unsigned char) *p++; 479 if (ttisp->tt_abbrind < 0 || 480 ttisp->tt_abbrind > sp->charcnt) 481 goto oops; 482 } 483 for (i = 0; i < sp->charcnt; ++i) 484 sp->chars[i] = *p++; 485 sp->chars[i] = '\0'; /* ensure '\0' at end */ 486 for (i = 0; i < sp->leapcnt; ++i) { 487 struct lsinfo * lsisp; 488 489 lsisp = &sp->lsis[i]; 490 lsisp->ls_trans = (time_t)((stored == 4) ? 491 detzcode(p) : detzcode64(p)); 492 p += stored; 493 lsisp->ls_corr = detzcode(p); 494 p += 4; 495 } 496 for (i = 0; i < sp->typecnt; ++i) { 497 struct ttinfo * ttisp; 498 499 ttisp = &sp->ttis[i]; 500 if (ttisstdcnt == 0) 501 ttisp->tt_ttisstd = FALSE; 502 else { 503 ttisp->tt_ttisstd = *p++; 504 if (ttisp->tt_ttisstd != TRUE && 505 ttisp->tt_ttisstd != FALSE) 506 goto oops; 507 } 508 } 509 for (i = 0; i < sp->typecnt; ++i) { 510 struct ttinfo * ttisp; 511 512 ttisp = &sp->ttis[i]; 513 if (ttisgmtcnt == 0) 514 ttisp->tt_ttisgmt = FALSE; 515 else { 516 ttisp->tt_ttisgmt = *p++; 517 if (ttisp->tt_ttisgmt != TRUE && 518 ttisp->tt_ttisgmt != FALSE) 519 goto oops; 520 } 521 } 522 /* 523 ** Out-of-sort ats should mean we're running on a 524 ** signed time_t system but using a data file with 525 ** unsigned values (or vice versa). 526 */ 527 for (i = 0; i < sp->timecnt; ++i) 528 if ((i < sp->timecnt - 1 && 529 sp->ats[i] > sp->ats[i + 1]) || 530 (i == sp->timecnt - 1 && !TYPE_SIGNED(time_t) && 531 sp->ats[i] > 532 ((stored == 4) ? INT32_MAX : INT64_MAX))) { 533 if (TYPE_SIGNED(time_t)) { 534 /* 535 ** Ignore the end (easy). 536 */ 537 sp->timecnt = i + 1; 538 } else { 539 /* 540 ** Ignore the beginning (harder). 541 */ 542 int j; 543 544 /* 545 ** Keep the record right before the 546 ** epoch boundary, 547 ** but tweak it so that it starts 548 ** right with the epoch 549 ** (thanks to Doug Bailey). 550 */ 551 sp->ats[i] = 0; 552 for (j = 0; j + i < sp->timecnt; ++j) { 553 sp->ats[j] = sp->ats[j + i]; 554 sp->types[j] = sp->types[j + i]; 555 } 556 sp->timecnt = j; 557 } 558 break; 559 } 560 /* 561 ** If this is an old file, we're done. 562 */ 563 if (up->tzhead.tzh_version[0] == '\0') 564 break; 565 nread -= p - up->buf; 566 for (i = 0; i < nread; ++i) 567 up->buf[i] = p[i]; 568 /* 569 ** If this is a narrow integer time_t system, we're done. 570 */ 571 if (stored >= (int) sizeof(time_t) 572 /* CONSTCOND */ 573 && TYPE_INTEGRAL(time_t)) 574 break; 575 } 576 if (doextend && nread > 2 && 577 up->buf[0] == '\n' && up->buf[nread - 1] == '\n' && 578 sp->typecnt + 2 <= TZ_MAX_TYPES) { 579 struct __state ts; 580 int result; 581 582 up->buf[nread - 1] = '\0'; 583 result = tzparse(&ts, &up->buf[1], FALSE); 584 if (result == 0 && ts.typecnt == 2 && 585 sp->charcnt + ts.charcnt <= TZ_MAX_CHARS) { 586 for (i = 0; i < 2; ++i) 587 ts.ttis[i].tt_abbrind += 588 sp->charcnt; 589 for (i = 0; i < ts.charcnt; ++i) 590 sp->chars[sp->charcnt++] = 591 ts.chars[i]; 592 i = 0; 593 while (i < ts.timecnt && 594 ts.ats[i] <= 595 sp->ats[sp->timecnt - 1]) 596 ++i; 597 while (i < ts.timecnt && 598 sp->timecnt < TZ_MAX_TIMES) { 599 sp->ats[sp->timecnt] = 600 ts.ats[i]; 601 sp->types[sp->timecnt] = 602 sp->typecnt + 603 ts.types[i]; 604 ++sp->timecnt; 605 ++i; 606 } 607 sp->ttis[sp->typecnt++] = ts.ttis[0]; 608 sp->ttis[sp->typecnt++] = ts.ttis[1]; 609 } 610 } 611 if (sp->timecnt > 1) { 612 for (i = 1; i < sp->timecnt; ++i) 613 if (typesequiv(sp, sp->types[i], sp->types[0]) && 614 differ_by_repeat(sp->ats[i], sp->ats[0])) { 615 sp->goback = TRUE; 616 break; 617 } 618 for (i = sp->timecnt - 2; i >= 0; --i) 619 if (typesequiv(sp, sp->types[sp->timecnt - 1], 620 sp->types[i]) && 621 differ_by_repeat(sp->ats[sp->timecnt - 1], 622 sp->ats[i])) { 623 sp->goahead = TRUE; 624 break; 625 } 626 } 627 /* 628 ** If type 0 is is unused in transitions, 629 ** it's the type to use for early times. 630 */ 631 for (i = 0; i < sp->typecnt; ++i) 632 if (sp->types[i] == 0) 633 break; 634 i = (i >= sp->typecnt) ? 0 : -1; 635 /* 636 ** Absent the above, 637 ** if there are transition times 638 ** and the first transition is to a daylight time 639 ** find the standard type less than and closest to 640 ** the type of the first transition. 641 */ 642 if (i < 0 && sp->timecnt > 0 && sp->ttis[sp->types[0]].tt_isdst) { 643 i = sp->types[0]; 644 while (--i >= 0) 645 if (!sp->ttis[i].tt_isdst) 646 break; 647 } 648 /* 649 ** If no result yet, find the first standard type. 650 ** If there is none, punt to type zero. 651 */ 652 if (i < 0) { 653 i = 0; 654 while (sp->ttis[i].tt_isdst) 655 if (++i >= sp->typecnt) { 656 i = 0; 657 break; 658 } 659 } 660 sp->defaulttype = i; 661 free(up); 662 return 0; 663 oops: 664 free(up); 665 return -1; 666 } 667 668 static int 669 typesequiv(const timezone_t sp, const int a, const int b) 670 { 671 int result; 672 673 if (sp == NULL || 674 a < 0 || a >= sp->typecnt || 675 b < 0 || b >= sp->typecnt) 676 result = FALSE; 677 else { 678 const struct ttinfo * ap = &sp->ttis[a]; 679 const struct ttinfo * bp = &sp->ttis[b]; 680 result = ap->tt_gmtoff == bp->tt_gmtoff && 681 ap->tt_isdst == bp->tt_isdst && 682 ap->tt_ttisstd == bp->tt_ttisstd && 683 ap->tt_ttisgmt == bp->tt_ttisgmt && 684 strcmp(&sp->chars[ap->tt_abbrind], 685 &sp->chars[bp->tt_abbrind]) == 0; 686 } 687 return result; 688 } 689 690 static const int mon_lengths[2][MONSPERYEAR] = { 691 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, 692 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } 693 }; 694 695 static const int year_lengths[2] = { 696 DAYSPERNYEAR, DAYSPERLYEAR 697 }; 698 699 /* 700 ** Given a pointer into a time zone string, scan until a character that is not 701 ** a valid character in a zone name is found. Return a pointer to that 702 ** character. 703 */ 704 705 static const char * 706 getzname(const char *strp) 707 { 708 char c; 709 710 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && 711 c != '+') 712 ++strp; 713 return strp; 714 } 715 716 /* 717 ** Given a pointer into an extended time zone string, scan until the ending 718 ** delimiter of the zone name is located. Return a pointer to the delimiter. 719 ** 720 ** As with getzname above, the legal character set is actually quite 721 ** restricted, with other characters producing undefined results. 722 ** We don't do any checking here; checking is done later in common-case code. 723 */ 724 725 static const char * 726 getqzname(const char *strp, const int delim) 727 { 728 int c; 729 730 while ((c = *strp) != '\0' && c != delim) 731 ++strp; 732 return strp; 733 } 734 735 /* 736 ** Given a pointer into a time zone string, extract a number from that string. 737 ** Check that the number is within a specified range; if it is not, return 738 ** NULL. 739 ** Otherwise, return a pointer to the first character not part of the number. 740 */ 741 742 static const char * 743 getnum(const char *strp, int *const nump, const int min, const int max) 744 { 745 char c; 746 int num; 747 748 if (strp == NULL || !is_digit(c = *strp)) { 749 errno = EINVAL; 750 return NULL; 751 } 752 num = 0; 753 do { 754 num = num * 10 + (c - '0'); 755 if (num > max) { 756 errno = EOVERFLOW; 757 return NULL; /* illegal value */ 758 } 759 c = *++strp; 760 } while (is_digit(c)); 761 if (num < min) { 762 errno = EINVAL; 763 return NULL; /* illegal value */ 764 } 765 *nump = num; 766 return strp; 767 } 768 769 /* 770 ** Given a pointer into a time zone string, extract a number of seconds, 771 ** in hh[:mm[:ss]] form, from the string. 772 ** If any error occurs, return NULL. 773 ** Otherwise, return a pointer to the first character not part of the number 774 ** of seconds. 775 */ 776 777 static const char * 778 getsecs(const char *strp, int_fast32_t *const secsp) 779 { 780 int num; 781 782 /* 783 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like 784 ** "M10.4.6/26", which does not conform to Posix, 785 ** but which specifies the equivalent of 786 ** ``02:00 on the first Sunday on or after 23 Oct''. 787 */ 788 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); 789 if (strp == NULL) 790 return NULL; 791 *secsp = num * (int_fast32_t) SECSPERHOUR; 792 if (*strp == ':') { 793 ++strp; 794 strp = getnum(strp, &num, 0, MINSPERHOUR - 1); 795 if (strp == NULL) 796 return NULL; 797 *secsp += num * SECSPERMIN; 798 if (*strp == ':') { 799 ++strp; 800 /* `SECSPERMIN' allows for leap seconds. */ 801 strp = getnum(strp, &num, 0, SECSPERMIN); 802 if (strp == NULL) 803 return NULL; 804 *secsp += num; 805 } 806 } 807 return strp; 808 } 809 810 /* 811 ** Given a pointer into a time zone string, extract an offset, in 812 ** [+-]hh[:mm[:ss]] form, from the string. 813 ** If any error occurs, return NULL. 814 ** Otherwise, return a pointer to the first character not part of the time. 815 */ 816 817 static const char * 818 getoffset(const char *strp, int_fast32_t *const offsetp) 819 { 820 int neg = 0; 821 822 if (*strp == '-') { 823 neg = 1; 824 ++strp; 825 } else if (*strp == '+') 826 ++strp; 827 strp = getsecs(strp, offsetp); 828 if (strp == NULL) 829 return NULL; /* illegal time */ 830 if (neg) 831 *offsetp = -*offsetp; 832 return strp; 833 } 834 835 /* 836 ** Given a pointer into a time zone string, extract a rule in the form 837 ** date[/time]. See POSIX section 8 for the format of "date" and "time". 838 ** If a valid rule is not found, return NULL. 839 ** Otherwise, return a pointer to the first character not part of the rule. 840 */ 841 842 static const char * 843 getrule(const char *strp, struct rule *const rulep) 844 { 845 if (*strp == 'J') { 846 /* 847 ** Julian day. 848 */ 849 rulep->r_type = JULIAN_DAY; 850 ++strp; 851 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); 852 } else if (*strp == 'M') { 853 /* 854 ** Month, week, day. 855 */ 856 rulep->r_type = MONTH_NTH_DAY_OF_WEEK; 857 ++strp; 858 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); 859 if (strp == NULL) 860 return NULL; 861 if (*strp++ != '.') 862 return NULL; 863 strp = getnum(strp, &rulep->r_week, 1, 5); 864 if (strp == NULL) 865 return NULL; 866 if (*strp++ != '.') 867 return NULL; 868 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); 869 } else if (is_digit(*strp)) { 870 /* 871 ** Day of year. 872 */ 873 rulep->r_type = DAY_OF_YEAR; 874 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); 875 } else return NULL; /* invalid format */ 876 if (strp == NULL) 877 return NULL; 878 if (*strp == '/') { 879 /* 880 ** Time specified. 881 */ 882 ++strp; 883 strp = getsecs(strp, &rulep->r_time); 884 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ 885 return strp; 886 } 887 888 /* 889 ** Given the Epoch-relative time of January 1, 00:00:00 UTC, in a year, the 890 ** year, a rule, and the offset from UTC at the time that rule takes effect, 891 ** calculate the Epoch-relative time that rule takes effect. 892 */ 893 894 static time_t 895 transtime(const time_t janfirst, const int year, const struct rule *const rulep, 896 const int_fast32_t offset) 897 { 898 int leapyear; 899 time_t value; 900 int i; 901 int d, m1, yy0, yy1, yy2, dow; 902 903 INITIALIZE(value); 904 leapyear = isleap(year); 905 switch (rulep->r_type) { 906 907 case JULIAN_DAY: 908 /* 909 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap 910 ** years. 911 ** In non-leap years, or if the day number is 59 or less, just 912 ** add SECSPERDAY times the day number-1 to the time of 913 ** January 1, midnight, to get the day. 914 */ 915 value = (time_t)(janfirst + (rulep->r_day - 1) * SECSPERDAY); 916 if (leapyear && rulep->r_day >= 60) 917 value += SECSPERDAY; 918 break; 919 920 case DAY_OF_YEAR: 921 /* 922 ** n - day of year. 923 ** Just add SECSPERDAY times the day number to the time of 924 ** January 1, midnight, to get the day. 925 */ 926 value = (time_t)(janfirst + rulep->r_day * SECSPERDAY); 927 break; 928 929 case MONTH_NTH_DAY_OF_WEEK: 930 /* 931 ** Mm.n.d - nth "dth day" of month m. 932 */ 933 value = janfirst; 934 for (i = 0; i < rulep->r_mon - 1; ++i) 935 value += (time_t)(mon_lengths[leapyear][i] * SECSPERDAY); 936 937 /* 938 ** Use Zeller's Congruence to get day-of-week of first day of 939 ** month. 940 */ 941 m1 = (rulep->r_mon + 9) % 12 + 1; 942 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; 943 yy1 = yy0 / 100; 944 yy2 = yy0 % 100; 945 dow = ((26 * m1 - 2) / 10 + 946 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; 947 if (dow < 0) 948 dow += DAYSPERWEEK; 949 950 /* 951 ** "dow" is the day-of-week of the first day of the month. Get 952 ** the day-of-month (zero-origin) of the first "dow" day of the 953 ** month. 954 */ 955 d = rulep->r_day - dow; 956 if (d < 0) 957 d += DAYSPERWEEK; 958 for (i = 1; i < rulep->r_week; ++i) { 959 if (d + DAYSPERWEEK >= 960 mon_lengths[leapyear][rulep->r_mon - 1]) 961 break; 962 d += DAYSPERWEEK; 963 } 964 965 /* 966 ** "d" is the day-of-month (zero-origin) of the day we want. 967 */ 968 value += (time_t)(d * SECSPERDAY); 969 break; 970 } 971 972 /* 973 ** "value" is the Epoch-relative time of 00:00:00 UTC on the day in 974 ** question. To get the Epoch-relative time of the specified local 975 ** time on that day, add the transition time and the current offset 976 ** from UTC. 977 */ 978 return (time_t)(value + rulep->r_time + offset); 979 } 980 981 /* 982 ** Given a POSIX section 8-style TZ string, fill in the rule tables as 983 ** appropriate. 984 */ 985 986 static int 987 tzparse(timezone_t sp, const char *name, const int lastditch) 988 { 989 const char * stdname; 990 const char * dstname; 991 size_t stdlen; 992 size_t dstlen; 993 int_fast32_t stdoffset; 994 int_fast32_t dstoffset; 995 time_t * atp; 996 unsigned char * typep; 997 char * cp; 998 int load_result; 999 1000 INITIALIZE(dstname); 1001 stdname = name; 1002 if (lastditch) { 1003 stdlen = strlen(name); /* length of standard zone name */ 1004 name += stdlen; 1005 if (stdlen >= sizeof sp->chars) 1006 stdlen = (sizeof sp->chars) - 1; 1007 stdoffset = 0; 1008 } else { 1009 if (*name == '<') { 1010 name++; 1011 stdname = name; 1012 name = getqzname(name, '>'); 1013 if (*name != '>') 1014 return (-1); 1015 stdlen = name - stdname; 1016 name++; 1017 } else { 1018 name = getzname(name); 1019 stdlen = name - stdname; 1020 } 1021 if (*name == '\0') 1022 return -1; 1023 name = getoffset(name, &stdoffset); 1024 if (name == NULL) 1025 return -1; 1026 } 1027 load_result = tzload(sp, TZDEFRULES, FALSE); 1028 if (load_result != 0) 1029 sp->leapcnt = 0; /* so, we're off a little */ 1030 if (*name != '\0') { 1031 if (*name == '<') { 1032 dstname = ++name; 1033 name = getqzname(name, '>'); 1034 if (*name != '>') 1035 return -1; 1036 dstlen = name - dstname; 1037 name++; 1038 } else { 1039 dstname = name; 1040 name = getzname(name); 1041 dstlen = name - dstname; /* length of DST zone name */ 1042 } 1043 if (*name != '\0' && *name != ',' && *name != ';') { 1044 name = getoffset(name, &dstoffset); 1045 if (name == NULL) 1046 return -1; 1047 } else dstoffset = stdoffset - SECSPERHOUR; 1048 if (*name == '\0' && load_result != 0) 1049 name = TZDEFRULESTRING; 1050 if (*name == ',' || *name == ';') { 1051 struct rule start; 1052 struct rule end; 1053 int year; 1054 time_t janfirst; 1055 time_t starttime; 1056 time_t endtime; 1057 1058 ++name; 1059 if ((name = getrule(name, &start)) == NULL) 1060 return -1; 1061 if (*name++ != ',') 1062 return -1; 1063 if ((name = getrule(name, &end)) == NULL) 1064 return -1; 1065 if (*name != '\0') 1066 return -1; 1067 sp->typecnt = 2; /* standard time and DST */ 1068 /* 1069 ** Two transitions per year, from EPOCH_YEAR forward. 1070 */ 1071 memset(sp->ttis, 0, sizeof(sp->ttis)); 1072 sp->ttis[0].tt_gmtoff = -dstoffset; 1073 sp->ttis[0].tt_isdst = 1; 1074 sp->ttis[0].tt_abbrind = (int)(stdlen + 1); 1075 sp->ttis[1].tt_gmtoff = -stdoffset; 1076 sp->ttis[1].tt_isdst = 0; 1077 sp->ttis[1].tt_abbrind = 0; 1078 atp = sp->ats; 1079 typep = sp->types; 1080 janfirst = 0; 1081 sp->timecnt = 0; 1082 for (year = EPOCH_YEAR; 1083 sp->timecnt + 2 <= TZ_MAX_TIMES; 1084 ++year) { 1085 time_t newfirst; 1086 1087 starttime = transtime(janfirst, year, &start, 1088 stdoffset); 1089 endtime = transtime(janfirst, year, &end, 1090 dstoffset); 1091 if (starttime > endtime) { 1092 *atp++ = endtime; 1093 *typep++ = 1; /* DST ends */ 1094 *atp++ = starttime; 1095 *typep++ = 0; /* DST begins */ 1096 } else { 1097 *atp++ = starttime; 1098 *typep++ = 0; /* DST begins */ 1099 *atp++ = endtime; 1100 *typep++ = 1; /* DST ends */ 1101 } 1102 sp->timecnt += 2; 1103 newfirst = janfirst; 1104 newfirst += (time_t) 1105 (year_lengths[isleap(year)] * SECSPERDAY); 1106 if (newfirst <= janfirst) 1107 break; 1108 janfirst = newfirst; 1109 } 1110 } else { 1111 int_fast32_t theirstdoffset; 1112 int_fast32_t theirdstoffset; 1113 int_fast32_t theiroffset; 1114 int isdst; 1115 int i; 1116 int j; 1117 1118 if (*name != '\0') 1119 return -1; 1120 /* 1121 ** Initial values of theirstdoffset and theirdstoffset. 1122 */ 1123 theirstdoffset = 0; 1124 for (i = 0; i < sp->timecnt; ++i) { 1125 j = sp->types[i]; 1126 if (!sp->ttis[j].tt_isdst) { 1127 theirstdoffset = 1128 -sp->ttis[j].tt_gmtoff; 1129 break; 1130 } 1131 } 1132 theirdstoffset = 0; 1133 for (i = 0; i < sp->timecnt; ++i) { 1134 j = sp->types[i]; 1135 if (sp->ttis[j].tt_isdst) { 1136 theirdstoffset = 1137 -sp->ttis[j].tt_gmtoff; 1138 break; 1139 } 1140 } 1141 /* 1142 ** Initially we're assumed to be in standard time. 1143 */ 1144 isdst = FALSE; 1145 theiroffset = theirstdoffset; 1146 /* 1147 ** Now juggle transition times and types 1148 ** tracking offsets as you do. 1149 */ 1150 for (i = 0; i < sp->timecnt; ++i) { 1151 j = sp->types[i]; 1152 sp->types[i] = sp->ttis[j].tt_isdst; 1153 if (sp->ttis[j].tt_ttisgmt) { 1154 /* No adjustment to transition time */ 1155 } else { 1156 /* 1157 ** If summer time is in effect, and the 1158 ** transition time was not specified as 1159 ** standard time, add the summer time 1160 ** offset to the transition time; 1161 ** otherwise, add the standard time 1162 ** offset to the transition time. 1163 */ 1164 /* 1165 ** Transitions from DST to DDST 1166 ** will effectively disappear since 1167 ** POSIX provides for only one DST 1168 ** offset. 1169 */ 1170 if (isdst && !sp->ttis[j].tt_ttisstd) { 1171 sp->ats[i] += (time_t) 1172 (dstoffset - theirdstoffset); 1173 } else { 1174 sp->ats[i] += (time_t) 1175 (stdoffset - theirstdoffset); 1176 } 1177 } 1178 theiroffset = -sp->ttis[j].tt_gmtoff; 1179 if (!sp->ttis[j].tt_isdst) 1180 theirstdoffset = theiroffset; 1181 else theirdstoffset = theiroffset; 1182 } 1183 /* 1184 ** Finally, fill in ttis. 1185 ** ttisstd and ttisgmt need not be handled 1186 */ 1187 memset(sp->ttis, 0, sizeof(sp->ttis)); 1188 sp->ttis[0].tt_gmtoff = -stdoffset; 1189 sp->ttis[0].tt_isdst = FALSE; 1190 sp->ttis[0].tt_abbrind = 0; 1191 sp->ttis[1].tt_gmtoff = -dstoffset; 1192 sp->ttis[1].tt_isdst = TRUE; 1193 sp->ttis[1].tt_abbrind = (int)(stdlen + 1); 1194 sp->typecnt = 2; 1195 } 1196 } else { 1197 dstlen = 0; 1198 sp->typecnt = 1; /* only standard time */ 1199 sp->timecnt = 0; 1200 memset(sp->ttis, 0, sizeof(sp->ttis)); 1201 sp->ttis[0].tt_gmtoff = -stdoffset; 1202 sp->ttis[0].tt_isdst = 0; 1203 sp->ttis[0].tt_abbrind = 0; 1204 } 1205 sp->charcnt = (int)(stdlen + 1); 1206 if (dstlen != 0) 1207 sp->charcnt += (int)(dstlen + 1); 1208 if ((size_t) sp->charcnt > sizeof sp->chars) 1209 return -1; 1210 cp = sp->chars; 1211 (void) strncpy(cp, stdname, stdlen); 1212 cp += stdlen; 1213 *cp++ = '\0'; 1214 if (dstlen != 0) { 1215 (void) strncpy(cp, dstname, dstlen); 1216 *(cp + dstlen) = '\0'; 1217 } 1218 return 0; 1219 } 1220 1221 static void 1222 gmtload(timezone_t sp) 1223 { 1224 if (tzload(sp, gmt, TRUE) != 0) 1225 (void) tzparse(sp, gmt, TRUE); 1226 } 1227 1228 timezone_t 1229 tzalloc(const char *name) 1230 { 1231 timezone_t sp = calloc(1, sizeof *sp); 1232 if (sp == NULL) 1233 return NULL; 1234 if (tzload(sp, name, TRUE) != 0) { 1235 free(sp); 1236 return NULL; 1237 } 1238 settzname_z(sp); 1239 return sp; 1240 } 1241 1242 void 1243 tzfree(const timezone_t sp) 1244 { 1245 free(sp); 1246 } 1247 1248 static void 1249 tzsetwall_unlocked(void) 1250 { 1251 if (lcl_is_set < 0) 1252 return; 1253 lcl_is_set = -1; 1254 1255 if (lclptr == NULL) { 1256 int saveerrno = errno; 1257 lclptr = calloc(1, sizeof *lclptr); 1258 errno = saveerrno; 1259 if (lclptr == NULL) { 1260 settzname(); /* all we can do */ 1261 return; 1262 } 1263 } 1264 if (tzload(lclptr, NULL, TRUE) != 0) 1265 gmtload(lclptr); 1266 settzname(); 1267 } 1268 1269 #ifndef STD_INSPIRED 1270 /* 1271 ** A non-static declaration of tzsetwall in a system header file 1272 ** may cause a warning about this upcoming static declaration... 1273 */ 1274 static 1275 #endif /* !defined STD_INSPIRED */ 1276 void 1277 tzsetwall(void) 1278 { 1279 rwlock_wrlock(&lcl_lock); 1280 tzsetwall_unlocked(); 1281 rwlock_unlock(&lcl_lock); 1282 } 1283 1284 #ifndef STD_INSPIRED 1285 /* 1286 ** A non-static declaration of tzsetwall in a system header file 1287 ** may cause a warning about this upcoming static declaration... 1288 */ 1289 static 1290 #endif /* !defined STD_INSPIRED */ 1291 void 1292 tzset_unlocked(void) 1293 { 1294 const char * name; 1295 1296 name = getenv("TZ"); 1297 if (name == NULL) { 1298 tzsetwall_unlocked(); 1299 return; 1300 } 1301 1302 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) 1303 return; 1304 lcl_is_set = strlen(name) < sizeof lcl_TZname; 1305 if (lcl_is_set) 1306 (void)strlcpy(lcl_TZname, name, sizeof(lcl_TZname)); 1307 1308 if (lclptr == NULL) { 1309 int saveerrno = errno; 1310 lclptr = calloc(1, sizeof *lclptr); 1311 errno = saveerrno; 1312 if (lclptr == NULL) { 1313 settzname(); /* all we can do */ 1314 return; 1315 } 1316 } 1317 if (*name == '\0') { 1318 /* 1319 ** User wants it fast rather than right. 1320 */ 1321 lclptr->leapcnt = 0; /* so, we're off a little */ 1322 lclptr->timecnt = 0; 1323 lclptr->typecnt = 0; 1324 lclptr->ttis[0].tt_isdst = 0; 1325 lclptr->ttis[0].tt_gmtoff = 0; 1326 lclptr->ttis[0].tt_abbrind = 0; 1327 (void) strlcpy(lclptr->chars, gmt, sizeof(lclptr->chars)); 1328 } else if (tzload(lclptr, name, TRUE) != 0) 1329 if (name[0] == ':' || tzparse(lclptr, name, FALSE) != 0) 1330 (void) gmtload(lclptr); 1331 settzname(); 1332 } 1333 1334 void 1335 tzset(void) 1336 { 1337 rwlock_wrlock(&lcl_lock); 1338 tzset_unlocked(); 1339 rwlock_unlock(&lcl_lock); 1340 } 1341 1342 /* 1343 ** The easy way to behave "as if no library function calls" localtime 1344 ** is to not call it--so we drop its guts into "localsub", which can be 1345 ** freely called. (And no, the PANS doesn't require the above behavior-- 1346 ** but it *is* desirable.) 1347 ** 1348 ** The unused offset argument is for the benefit of mktime variants. 1349 */ 1350 1351 /*ARGSUSED*/ 1352 static struct tm * 1353 localsub(const timezone_t sp, const time_t * const timep, const int_fast32_t offset, 1354 struct tm *const tmp) 1355 { 1356 const struct ttinfo * ttisp; 1357 int i; 1358 struct tm * result; 1359 const time_t t = *timep; 1360 1361 if ((sp->goback && t < sp->ats[0]) || 1362 (sp->goahead && t > sp->ats[sp->timecnt - 1])) { 1363 time_t newt = t; 1364 time_t seconds; 1365 time_t tcycles; 1366 int_fast64_t icycles; 1367 1368 if (t < sp->ats[0]) 1369 seconds = sp->ats[0] - t; 1370 else seconds = t - sp->ats[sp->timecnt - 1]; 1371 --seconds; 1372 tcycles = (time_t) 1373 (seconds / YEARSPERREPEAT / AVGSECSPERYEAR); 1374 ++tcycles; 1375 icycles = tcycles; 1376 if (tcycles - icycles >= 1 || icycles - tcycles >= 1) 1377 return NULL; 1378 seconds = (time_t) icycles; 1379 seconds *= YEARSPERREPEAT; 1380 seconds *= AVGSECSPERYEAR; 1381 if (t < sp->ats[0]) 1382 newt += seconds; 1383 else newt -= seconds; 1384 if (newt < sp->ats[0] || 1385 newt > sp->ats[sp->timecnt - 1]) 1386 return NULL; /* "cannot happen" */ 1387 result = localsub(sp, &newt, offset, tmp); 1388 if (result == tmp) { 1389 time_t newy; 1390 1391 newy = tmp->tm_year; 1392 if (t < sp->ats[0]) 1393 newy -= (time_t)icycles * YEARSPERREPEAT; 1394 else newy += (time_t)icycles * YEARSPERREPEAT; 1395 tmp->tm_year = (int)newy; 1396 if (tmp->tm_year != newy) 1397 return NULL; 1398 } 1399 return result; 1400 } 1401 if (sp->timecnt == 0 || t < sp->ats[0]) { 1402 i = sp->defaulttype; 1403 } else { 1404 int lo = 1; 1405 int hi = sp->timecnt; 1406 1407 while (lo < hi) { 1408 int mid = (lo + hi) / 2; 1409 1410 if (t < sp->ats[mid]) 1411 hi = mid; 1412 else lo = mid + 1; 1413 } 1414 i = (int) sp->types[lo - 1]; 1415 } 1416 ttisp = &sp->ttis[i]; 1417 /* 1418 ** To get (wrong) behavior that's compatible with System V Release 2.0 1419 ** you'd replace the statement below with 1420 ** t += ttisp->tt_gmtoff; 1421 ** timesub(&t, 0L, sp, tmp); 1422 */ 1423 result = timesub(sp, &t, ttisp->tt_gmtoff, tmp); 1424 tmp->tm_isdst = ttisp->tt_isdst; 1425 if (sp == lclptr) 1426 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind]; 1427 #ifdef TM_ZONE 1428 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind]; 1429 #endif /* defined TM_ZONE */ 1430 return result; 1431 } 1432 1433 /* 1434 ** Re-entrant version of localtime. 1435 */ 1436 1437 struct tm * 1438 localtime_r(const time_t * __restrict timep, struct tm *tmp) 1439 { 1440 rwlock_rdlock(&lcl_lock); 1441 tzset_unlocked(); 1442 tmp = localtime_rz(lclptr, timep, tmp); 1443 rwlock_unlock(&lcl_lock); 1444 return tmp; 1445 } 1446 1447 struct tm * 1448 localtime(const time_t *const timep) 1449 { 1450 return localtime_r(timep, &tm); 1451 } 1452 1453 struct tm * 1454 localtime_rz(const timezone_t sp, const time_t * __restrict timep, struct tm *tmp) 1455 { 1456 if (sp == NULL) 1457 tmp = gmtsub(NULL, timep, 0, tmp); 1458 else 1459 tmp = localsub(sp, timep, 0, tmp); 1460 if (tmp == NULL) 1461 errno = EOVERFLOW; 1462 return tmp; 1463 } 1464 1465 /* 1466 ** gmtsub is to gmtime as localsub is to localtime. 1467 */ 1468 1469 static struct tm * 1470 gmtsub(const timezone_t sp, const time_t *const timep, 1471 const int_fast32_t offset, struct tm *const tmp) 1472 { 1473 struct tm * result; 1474 #ifdef _REENTRANT 1475 static mutex_t gmt_mutex = MUTEX_INITIALIZER; 1476 #endif 1477 1478 mutex_lock(&gmt_mutex); 1479 if (!gmt_is_set) { 1480 int saveerrno; 1481 gmt_is_set = TRUE; 1482 saveerrno = errno; 1483 gmtptr = calloc(1, sizeof *gmtptr); 1484 errno = saveerrno; 1485 if (gmtptr != NULL) 1486 gmtload(gmtptr); 1487 } 1488 mutex_unlock(&gmt_mutex); 1489 result = timesub(gmtptr, timep, offset, tmp); 1490 #ifdef TM_ZONE 1491 /* 1492 ** Could get fancy here and deliver something such as 1493 ** "UTC+xxxx" or "UTC-xxxx" if offset is non-zero, 1494 ** but this is no time for a treasure hunt. 1495 */ 1496 if (offset != 0) 1497 tmp->TM_ZONE = (__aconst char *)__UNCONST(wildabbr); 1498 else { 1499 if (gmtptr == NULL) 1500 tmp->TM_ZONE = (__aconst char *)__UNCONST(gmt); 1501 else tmp->TM_ZONE = gmtptr->chars; 1502 } 1503 #endif /* defined TM_ZONE */ 1504 return result; 1505 } 1506 1507 struct tm * 1508 gmtime(const time_t *const timep) 1509 { 1510 struct tm *tmp = gmtsub(NULL, timep, 0, &tm); 1511 1512 if (tmp == NULL) 1513 errno = EOVERFLOW; 1514 1515 return tmp; 1516 } 1517 1518 /* 1519 ** Re-entrant version of gmtime. 1520 */ 1521 1522 struct tm * 1523 gmtime_r(const time_t * const timep, struct tm *tmp) 1524 { 1525 tmp = gmtsub(NULL, timep, 0, tmp); 1526 1527 if (tmp == NULL) 1528 errno = EOVERFLOW; 1529 1530 return tmp; 1531 } 1532 1533 #ifdef STD_INSPIRED 1534 1535 struct tm * 1536 offtime(const time_t *const timep, long offset) 1537 { 1538 struct tm *tmp; 1539 1540 if ((offset > 0 && offset > INT_FAST32_MAX) || 1541 (offset < 0 && offset < INT_FAST32_MIN)) { 1542 errno = EOVERFLOW; 1543 return NULL; 1544 } 1545 tmp = gmtsub(NULL, timep, (int_fast32_t)offset, &tm); 1546 1547 if (tmp == NULL) 1548 errno = EOVERFLOW; 1549 1550 return tmp; 1551 } 1552 1553 struct tm * 1554 offtime_r(const time_t *timep, long offset, struct tm *tmp) 1555 { 1556 if ((offset > 0 && offset > INT_FAST32_MAX) || 1557 (offset < 0 && offset < INT_FAST32_MIN)) { 1558 errno = EOVERFLOW; 1559 return NULL; 1560 } 1561 tmp = gmtsub(NULL, timep, (int_fast32_t)offset, tmp); 1562 1563 if (tmp == NULL) 1564 errno = EOVERFLOW; 1565 1566 return tmp; 1567 } 1568 1569 #endif /* defined STD_INSPIRED */ 1570 1571 /* 1572 ** Return the number of leap years through the end of the given year 1573 ** where, to make the math easy, the answer for year zero is defined as zero. 1574 */ 1575 1576 static int 1577 leaps_thru_end_of(const int y) 1578 { 1579 return (y >= 0) ? (y / 4 - y / 100 + y / 400) : 1580 -(leaps_thru_end_of(-(y + 1)) + 1); 1581 } 1582 1583 static struct tm * 1584 timesub(const timezone_t sp, const time_t *const timep, 1585 const int_fast32_t offset, struct tm *const tmp) 1586 { 1587 const struct lsinfo * lp; 1588 time_t tdays; 1589 int idays; /* unsigned would be so 2003 */ 1590 int_fast64_t rem; 1591 int y; 1592 const int * ip; 1593 int_fast64_t corr; 1594 int hit; 1595 int i; 1596 1597 corr = 0; 1598 hit = 0; 1599 i = (sp == NULL) ? 0 : sp->leapcnt; 1600 while (--i >= 0) { 1601 lp = &sp->lsis[i]; 1602 if (*timep >= lp->ls_trans) { 1603 if (*timep == lp->ls_trans) { 1604 hit = ((i == 0 && lp->ls_corr > 0) || 1605 lp->ls_corr > sp->lsis[i - 1].ls_corr); 1606 if (hit) 1607 while (i > 0 && 1608 sp->lsis[i].ls_trans == 1609 sp->lsis[i - 1].ls_trans + 1 && 1610 sp->lsis[i].ls_corr == 1611 sp->lsis[i - 1].ls_corr + 1) { 1612 ++hit; 1613 --i; 1614 } 1615 } 1616 corr = lp->ls_corr; 1617 break; 1618 } 1619 } 1620 y = EPOCH_YEAR; 1621 tdays = (time_t)(*timep / SECSPERDAY); 1622 rem = (int_fast64_t) (*timep - tdays * SECSPERDAY); 1623 while (tdays < 0 || tdays >= year_lengths[isleap(y)]) { 1624 int newy; 1625 time_t tdelta; 1626 int idelta; 1627 int leapdays; 1628 1629 tdelta = tdays / DAYSPERLYEAR; 1630 idelta = (int) tdelta; 1631 if (tdelta - idelta >= 1 || idelta - tdelta >= 1) 1632 return NULL; 1633 if (idelta == 0) 1634 idelta = (tdays < 0) ? -1 : 1; 1635 newy = y; 1636 if (increment_overflow(&newy, idelta)) 1637 return NULL; 1638 leapdays = leaps_thru_end_of(newy - 1) - 1639 leaps_thru_end_of(y - 1); 1640 tdays -= ((time_t) newy - y) * DAYSPERNYEAR; 1641 tdays -= leapdays; 1642 y = newy; 1643 } 1644 { 1645 int_fast32_t seconds; 1646 const time_t half_second = (time_t)0.5; 1647 1648 seconds = (int_fast32_t)(tdays * SECSPERDAY + half_second); 1649 tdays = (time_t)(seconds / SECSPERDAY); 1650 rem += (int_fast64_t)(seconds - tdays * SECSPERDAY); 1651 } 1652 /* 1653 ** Given the range, we can now fearlessly cast... 1654 */ 1655 idays = (int) tdays; 1656 rem += offset - corr; 1657 while (rem < 0) { 1658 rem += SECSPERDAY; 1659 --idays; 1660 } 1661 while (rem >= SECSPERDAY) { 1662 rem -= SECSPERDAY; 1663 ++idays; 1664 } 1665 while (idays < 0) { 1666 if (increment_overflow(&y, -1)) 1667 return NULL; 1668 idays += year_lengths[isleap(y)]; 1669 } 1670 while (idays >= year_lengths[isleap(y)]) { 1671 idays -= year_lengths[isleap(y)]; 1672 if (increment_overflow(&y, 1)) 1673 return NULL; 1674 } 1675 tmp->tm_year = y; 1676 if (increment_overflow(&tmp->tm_year, -TM_YEAR_BASE)) 1677 return NULL; 1678 tmp->tm_yday = idays; 1679 /* 1680 ** The "extra" mods below avoid overflow problems. 1681 */ 1682 tmp->tm_wday = EPOCH_WDAY + 1683 ((y - EPOCH_YEAR) % DAYSPERWEEK) * 1684 (DAYSPERNYEAR % DAYSPERWEEK) + 1685 leaps_thru_end_of(y - 1) - 1686 leaps_thru_end_of(EPOCH_YEAR - 1) + 1687 idays; 1688 tmp->tm_wday %= DAYSPERWEEK; 1689 if (tmp->tm_wday < 0) 1690 tmp->tm_wday += DAYSPERWEEK; 1691 tmp->tm_hour = (int) (rem / SECSPERHOUR); 1692 rem %= SECSPERHOUR; 1693 tmp->tm_min = (int) (rem / SECSPERMIN); 1694 /* 1695 ** A positive leap second requires a special 1696 ** representation. This uses "... ??:59:60" et seq. 1697 */ 1698 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit; 1699 ip = mon_lengths[isleap(y)]; 1700 for (tmp->tm_mon = 0; idays >= ip[tmp->tm_mon]; ++(tmp->tm_mon)) 1701 idays -= ip[tmp->tm_mon]; 1702 tmp->tm_mday = (int) (idays + 1); 1703 tmp->tm_isdst = 0; 1704 #ifdef TM_GMTOFF 1705 tmp->TM_GMTOFF = offset; 1706 #endif /* defined TM_GMTOFF */ 1707 return tmp; 1708 } 1709 1710 char * 1711 ctime(const time_t *const timep) 1712 { 1713 /* 1714 ** Section 4.12.3.2 of X3.159-1989 requires that 1715 ** The ctime function converts the calendar time pointed to by timer 1716 ** to local time in the form of a string. It is equivalent to 1717 ** asctime(localtime(timer)) 1718 */ 1719 struct tm *rtm = localtime(timep); 1720 if (rtm == NULL) 1721 return NULL; 1722 return asctime(rtm); 1723 } 1724 1725 char * 1726 ctime_r(const time_t *const timep, char *buf) 1727 { 1728 struct tm mytm, *rtm; 1729 1730 rtm = localtime_r(timep, &mytm); 1731 if (rtm == NULL) 1732 return NULL; 1733 return asctime_r(rtm, buf); 1734 } 1735 1736 char * 1737 ctime_rz(const timezone_t sp, const time_t * timep, char *buf) 1738 { 1739 struct tm mytm, *rtm; 1740 1741 rtm = localtime_rz(sp, timep, &mytm); 1742 if (rtm == NULL) 1743 return NULL; 1744 return asctime_r(rtm, buf); 1745 } 1746 1747 /* 1748 ** Adapted from code provided by Robert Elz, who writes: 1749 ** The "best" way to do mktime I think is based on an idea of Bob 1750 ** Kridle's (so its said...) from a long time ago. 1751 ** It does a binary search of the time_t space. Since time_t's are 1752 ** just 32 bits, its a max of 32 iterations (even at 64 bits it 1753 ** would still be very reasonable). 1754 */ 1755 1756 #ifndef WRONG 1757 #define WRONG ((time_t)-1) 1758 #endif /* !defined WRONG */ 1759 1760 /* 1761 ** Simplified normalize logic courtesy Paul Eggert. 1762 */ 1763 1764 static int 1765 increment_overflow(int *const ip, int j) 1766 { 1767 int i = *ip; 1768 1769 /* 1770 ** If i >= 0 there can only be overflow if i + j > INT_MAX 1771 ** or if j > INT_MAX - i; given i >= 0, INT_MAX - i cannot overflow. 1772 ** If i < 0 there can only be overflow if i + j < INT_MIN 1773 ** or if j < INT_MIN - i; given i < 0, INT_MIN - i cannot overflow. 1774 */ 1775 if ((i >= 0) ? (j > INT_MAX - i) : (j < INT_MIN - i)) 1776 return TRUE; 1777 *ip += j; 1778 return FALSE; 1779 } 1780 1781 static int 1782 increment_overflow32(int_fast32_t *const lp, int const m) 1783 { 1784 int_fast32_t l = *lp; 1785 1786 if ((l >= 0) ? (m > INT_FAST32_MAX - l) : (m < INT_FAST32_MIN - l)) 1787 return TRUE; 1788 *lp += m; 1789 return FALSE; 1790 } 1791 1792 static int 1793 normalize_overflow(int *const tensptr, int *const unitsptr, const int base) 1794 { 1795 int tensdelta; 1796 1797 tensdelta = (*unitsptr >= 0) ? 1798 (*unitsptr / base) : 1799 (-1 - (-1 - *unitsptr) / base); 1800 *unitsptr -= tensdelta * base; 1801 return increment_overflow(tensptr, tensdelta); 1802 } 1803 1804 static int 1805 normalize_overflow32(int_fast32_t *const tensptr, int *const unitsptr, 1806 const int base) 1807 { 1808 int tensdelta; 1809 1810 tensdelta = (*unitsptr >= 0) ? 1811 (*unitsptr / base) : 1812 (-1 - (-1 - *unitsptr) / base); 1813 *unitsptr -= tensdelta * base; 1814 return increment_overflow32(tensptr, tensdelta); 1815 } 1816 1817 static int 1818 tmcomp(const struct tm *const atmp, const struct tm *const btmp) 1819 { 1820 int result; 1821 1822 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 && 1823 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 && 1824 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && 1825 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && 1826 (result = (atmp->tm_min - btmp->tm_min)) == 0) 1827 result = atmp->tm_sec - btmp->tm_sec; 1828 return result; 1829 } 1830 1831 static time_t 1832 time2sub(const timezone_t sp, struct tm *const tmp, subfun_t funcp, 1833 const int_fast32_t offset, int *const okayp, const int do_norm_secs) 1834 { 1835 int dir; 1836 int i, j; 1837 int saved_seconds; 1838 int_fast32_t li; 1839 time_t lo; 1840 time_t hi; 1841 #ifdef NO_ERROR_IN_DST_GAP 1842 time_t ilo; 1843 #endif 1844 int_fast32_t y; 1845 time_t newt; 1846 time_t t; 1847 struct tm yourtm, mytm; 1848 1849 *okayp = FALSE; 1850 yourtm = *tmp; 1851 #ifdef NO_ERROR_IN_DST_GAP 1852 again: 1853 #endif 1854 if (do_norm_secs) { 1855 if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec, 1856 SECSPERMIN)) 1857 goto overflow; 1858 } 1859 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) 1860 goto overflow; 1861 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) 1862 goto overflow; 1863 y = yourtm.tm_year; 1864 if (normalize_overflow32(&y, &yourtm.tm_mon, MONSPERYEAR)) 1865 goto overflow; 1866 /* 1867 ** Turn y into an actual year number for now. 1868 ** It is converted back to an offset from TM_YEAR_BASE later. 1869 */ 1870 if (increment_overflow32(&y, TM_YEAR_BASE)) 1871 goto overflow; 1872 while (yourtm.tm_mday <= 0) { 1873 if (increment_overflow32(&y, -1)) 1874 goto overflow; 1875 li = y + (1 < yourtm.tm_mon); 1876 yourtm.tm_mday += year_lengths[isleap(li)]; 1877 } 1878 while (yourtm.tm_mday > DAYSPERLYEAR) { 1879 li = y + (1 < yourtm.tm_mon); 1880 yourtm.tm_mday -= year_lengths[isleap(li)]; 1881 if (increment_overflow32(&y, 1)) 1882 goto overflow; 1883 } 1884 for ( ; ; ) { 1885 i = mon_lengths[isleap(y)][yourtm.tm_mon]; 1886 if (yourtm.tm_mday <= i) 1887 break; 1888 yourtm.tm_mday -= i; 1889 if (++yourtm.tm_mon >= MONSPERYEAR) { 1890 yourtm.tm_mon = 0; 1891 if (increment_overflow32(&y, 1)) 1892 goto overflow; 1893 } 1894 } 1895 if (increment_overflow32(&y, -TM_YEAR_BASE)) 1896 goto overflow; 1897 yourtm.tm_year = (int)y; 1898 if (yourtm.tm_year != y) 1899 goto overflow; 1900 if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN) 1901 saved_seconds = 0; 1902 else if (y + TM_YEAR_BASE < EPOCH_YEAR) { 1903 /* 1904 ** We can't set tm_sec to 0, because that might push the 1905 ** time below the minimum representable time. 1906 ** Set tm_sec to 59 instead. 1907 ** This assumes that the minimum representable time is 1908 ** not in the same minute that a leap second was deleted from, 1909 ** which is a safer assumption than using 58 would be. 1910 */ 1911 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) 1912 goto overflow; 1913 saved_seconds = yourtm.tm_sec; 1914 yourtm.tm_sec = SECSPERMIN - 1; 1915 } else { 1916 saved_seconds = yourtm.tm_sec; 1917 yourtm.tm_sec = 0; 1918 } 1919 /* 1920 ** Do a binary search (this works whatever time_t's type is). 1921 */ 1922 /* LINTED const not */ 1923 if (!TYPE_SIGNED(time_t)) { 1924 lo = 0; 1925 hi = lo - 1; 1926 /* LINTED const not */ 1927 } else if (!TYPE_INTEGRAL(time_t)) { 1928 /* CONSTCOND */ 1929 if (sizeof(time_t) > sizeof(float)) 1930 /* LINTED assumed double */ 1931 hi = (time_t) DBL_MAX; 1932 /* LINTED assumed float */ 1933 else hi = (time_t) FLT_MAX; 1934 lo = -hi; 1935 } else { 1936 lo = 1; 1937 for (i = 0; i < (int) TYPE_BIT(time_t) - 1; ++i) 1938 lo *= 2; 1939 hi = -(lo + 1); 1940 } 1941 #ifdef NO_ERROR_IN_DST_GAP 1942 ilo = lo; 1943 #endif 1944 for ( ; ; ) { 1945 t = lo / 2 + hi / 2; 1946 if (t < lo) 1947 t = lo; 1948 else if (t > hi) 1949 t = hi; 1950 if ((*funcp)(sp, &t, offset, &mytm) == NULL) { 1951 /* 1952 ** Assume that t is too extreme to be represented in 1953 ** a struct tm; arrange things so that it is less 1954 ** extreme on the next pass. 1955 */ 1956 dir = (t > 0) ? 1 : -1; 1957 } else dir = tmcomp(&mytm, &yourtm); 1958 if (dir != 0) { 1959 if (t == lo) { 1960 ++t; 1961 if (t <= lo) 1962 goto overflow; 1963 ++lo; 1964 } else if (t == hi) { 1965 --t; 1966 if (t >= hi) 1967 goto overflow; 1968 --hi; 1969 } 1970 #ifdef NO_ERROR_IN_DST_GAP 1971 if (ilo != lo && lo - 1 == hi && yourtm.tm_isdst < 0 && 1972 do_norm_secs) { 1973 for (i = sp->typecnt - 1; i >= 0; --i) { 1974 for (j = sp->typecnt - 1; j >= 0; --j) { 1975 time_t off; 1976 if (sp->ttis[j].tt_isdst == 1977 sp->ttis[i].tt_isdst) 1978 continue; 1979 off = sp->ttis[j].tt_gmtoff - 1980 sp->ttis[i].tt_gmtoff; 1981 yourtm.tm_sec += off < 0 ? 1982 -off : off; 1983 goto again; 1984 } 1985 } 1986 } 1987 #endif 1988 if (lo > hi) 1989 goto invalid; 1990 if (dir > 0) 1991 hi = t; 1992 else lo = t; 1993 continue; 1994 } 1995 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) 1996 break; 1997 /* 1998 ** Right time, wrong type. 1999 ** Hunt for right time, right type. 2000 ** It's okay to guess wrong since the guess 2001 ** gets checked. 2002 */ 2003 if (sp == NULL) 2004 goto invalid; 2005 for (i = sp->typecnt - 1; i >= 0; --i) { 2006 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) 2007 continue; 2008 for (j = sp->typecnt - 1; j >= 0; --j) { 2009 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) 2010 continue; 2011 newt = (time_t)(t + sp->ttis[j].tt_gmtoff - 2012 sp->ttis[i].tt_gmtoff); 2013 if ((*funcp)(sp, &newt, offset, &mytm) == NULL) 2014 continue; 2015 if (tmcomp(&mytm, &yourtm) != 0) 2016 continue; 2017 if (mytm.tm_isdst != yourtm.tm_isdst) 2018 continue; 2019 /* 2020 ** We have a match. 2021 */ 2022 t = newt; 2023 goto label; 2024 } 2025 } 2026 goto invalid; 2027 } 2028 label: 2029 newt = t + saved_seconds; 2030 if ((newt < t) != (saved_seconds < 0)) 2031 goto overflow; 2032 t = newt; 2033 if ((*funcp)(sp, &t, offset, tmp)) { 2034 *okayp = TRUE; 2035 return t; 2036 } 2037 overflow: 2038 errno = EOVERFLOW; 2039 return WRONG; 2040 invalid: 2041 errno = EINVAL; 2042 return WRONG; 2043 } 2044 2045 static time_t 2046 time2(const timezone_t sp, struct tm *const tmp, subfun_t funcp, 2047 const int_fast32_t offset, int *const okayp) 2048 { 2049 time_t t; 2050 2051 /* 2052 ** First try without normalization of seconds 2053 ** (in case tm_sec contains a value associated with a leap second). 2054 ** If that fails, try with normalization of seconds. 2055 */ 2056 t = time2sub(sp, tmp, funcp, offset, okayp, FALSE); 2057 return *okayp ? t : time2sub(sp, tmp, funcp, offset, okayp, TRUE); 2058 } 2059 2060 static time_t 2061 time1(const timezone_t sp, struct tm *const tmp, subfun_t funcp, 2062 const int_fast32_t offset) 2063 { 2064 time_t t; 2065 int samei, otheri; 2066 int sameind, otherind; 2067 int i; 2068 int nseen; 2069 int seen[TZ_MAX_TYPES]; 2070 int types[TZ_MAX_TYPES]; 2071 int okay; 2072 2073 if (tmp == NULL) { 2074 errno = EINVAL; 2075 return WRONG; 2076 } 2077 if (tmp->tm_isdst > 1) 2078 tmp->tm_isdst = 1; 2079 t = time2(sp, tmp, funcp, offset, &okay); 2080 #ifdef PCTS 2081 /* 2082 ** PCTS code courtesy Grant Sullivan. 2083 */ 2084 if (okay) 2085 return t; 2086 if (tmp->tm_isdst < 0) 2087 tmp->tm_isdst = 0; /* reset to std and try again */ 2088 #endif /* defined PCTS */ 2089 #ifndef PCTS 2090 if (okay || tmp->tm_isdst < 0) 2091 return t; 2092 #endif /* !defined PCTS */ 2093 /* 2094 ** We're supposed to assume that somebody took a time of one type 2095 ** and did some math on it that yielded a "struct tm" that's bad. 2096 ** We try to divine the type they started from and adjust to the 2097 ** type they need. 2098 */ 2099 if (sp == NULL) { 2100 errno = EINVAL; 2101 return WRONG; 2102 } 2103 for (i = 0; i < sp->typecnt; ++i) 2104 seen[i] = FALSE; 2105 nseen = 0; 2106 for (i = sp->timecnt - 1; i >= 0; --i) 2107 if (!seen[sp->types[i]]) { 2108 seen[sp->types[i]] = TRUE; 2109 types[nseen++] = sp->types[i]; 2110 } 2111 for (sameind = 0; sameind < nseen; ++sameind) { 2112 samei = types[sameind]; 2113 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) 2114 continue; 2115 for (otherind = 0; otherind < nseen; ++otherind) { 2116 otheri = types[otherind]; 2117 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) 2118 continue; 2119 tmp->tm_sec += (int)(sp->ttis[otheri].tt_gmtoff - 2120 sp->ttis[samei].tt_gmtoff); 2121 tmp->tm_isdst = !tmp->tm_isdst; 2122 t = time2(sp, tmp, funcp, offset, &okay); 2123 if (okay) 2124 return t; 2125 tmp->tm_sec -= (int)(sp->ttis[otheri].tt_gmtoff - 2126 sp->ttis[samei].tt_gmtoff); 2127 tmp->tm_isdst = !tmp->tm_isdst; 2128 } 2129 } 2130 errno = EOVERFLOW; 2131 return WRONG; 2132 } 2133 2134 time_t 2135 mktime_z(const timezone_t sp, struct tm *const tmp) 2136 { 2137 time_t t; 2138 if (sp == NULL) 2139 t = time1(NULL, tmp, gmtsub, 0); 2140 else 2141 t = time1(sp, tmp, localsub, 0); 2142 return t; 2143 } 2144 2145 time_t 2146 mktime(struct tm *const tmp) 2147 { 2148 time_t result; 2149 2150 rwlock_wrlock(&lcl_lock); 2151 tzset_unlocked(); 2152 result = mktime_z(lclptr, tmp); 2153 rwlock_unlock(&lcl_lock); 2154 return result; 2155 } 2156 2157 #ifdef STD_INSPIRED 2158 2159 time_t 2160 timelocal_z(const timezone_t sp, struct tm *const tmp) 2161 { 2162 if (tmp != NULL) 2163 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 2164 return mktime_z(sp, tmp); 2165 } 2166 2167 time_t 2168 timelocal(struct tm *const tmp) 2169 { 2170 if (tmp != NULL) 2171 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 2172 return mktime(tmp); 2173 } 2174 2175 time_t 2176 timegm(struct tm *const tmp) 2177 { 2178 time_t t; 2179 2180 if (tmp != NULL) 2181 tmp->tm_isdst = 0; 2182 t = time1(gmtptr, tmp, gmtsub, 0); 2183 return t; 2184 } 2185 2186 time_t 2187 timeoff(struct tm *const tmp, long offset) 2188 { 2189 time_t t; 2190 2191 if ((offset > 0 && offset > INT_FAST32_MAX) || 2192 (offset < 0 && offset < INT_FAST32_MIN)) { 2193 errno = EOVERFLOW; 2194 return -1; 2195 } 2196 if (tmp != NULL) 2197 tmp->tm_isdst = 0; 2198 t = time1(gmtptr, tmp, gmtsub, (int_fast32_t)offset); 2199 return t; 2200 } 2201 2202 #endif /* defined STD_INSPIRED */ 2203 2204 #ifdef CMUCS 2205 2206 /* 2207 ** The following is supplied for compatibility with 2208 ** previous versions of the CMUCS runtime library. 2209 */ 2210 2211 int_fast32_t 2212 gtime(struct tm *const tmp) 2213 { 2214 const time_t t = mktime(tmp); 2215 2216 if (t == WRONG) 2217 return -1; 2218 return t; 2219 } 2220 2221 #endif /* defined CMUCS */ 2222 2223 /* 2224 ** XXX--is the below the right way to conditionalize?? 2225 */ 2226 2227 #ifdef STD_INSPIRED 2228 2229 /* 2230 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 2231 ** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which 2232 ** is not the case if we are accounting for leap seconds. 2233 ** So, we provide the following conversion routines for use 2234 ** when exchanging timestamps with POSIX conforming systems. 2235 */ 2236 2237 static int_fast64_t 2238 leapcorr(const timezone_t sp, time_t *timep) 2239 { 2240 struct lsinfo * lp; 2241 int i; 2242 2243 i = sp->leapcnt; 2244 while (--i >= 0) { 2245 lp = &sp->lsis[i]; 2246 if (*timep >= lp->ls_trans) 2247 return lp->ls_corr; 2248 } 2249 return 0; 2250 } 2251 2252 time_t 2253 time2posix_z(const timezone_t sp, time_t t) 2254 { 2255 return (time_t)(t - leapcorr(sp, &t)); 2256 } 2257 2258 time_t 2259 time2posix(time_t t) 2260 { 2261 time_t result; 2262 rwlock_wrlock(&lcl_lock); 2263 tzset_unlocked(); 2264 result = (time_t)(t - leapcorr(lclptr, &t)); 2265 rwlock_unlock(&lcl_lock); 2266 return (result); 2267 } 2268 2269 time_t 2270 posix2time_z(const timezone_t sp, time_t t) 2271 { 2272 time_t x; 2273 time_t y; 2274 2275 /* 2276 ** For a positive leap second hit, the result 2277 ** is not unique. For a negative leap second 2278 ** hit, the corresponding time doesn't exist, 2279 ** so we return an adjacent second. 2280 */ 2281 x = (time_t)(t + leapcorr(sp, &t)); 2282 y = (time_t)(x - leapcorr(sp, &x)); 2283 if (y < t) { 2284 do { 2285 x++; 2286 y = (time_t)(x - leapcorr(sp, &x)); 2287 } while (y < t); 2288 if (t != y) { 2289 return x - 1; 2290 } 2291 } else if (y > t) { 2292 do { 2293 --x; 2294 y = (time_t)(x - leapcorr(sp, &x)); 2295 } while (y > t); 2296 if (t != y) { 2297 return x + 1; 2298 } 2299 } 2300 return x; 2301 } 2302 2303 2304 2305 time_t 2306 posix2time(time_t t) 2307 { 2308 time_t result; 2309 2310 rwlock_wrlock(&lcl_lock); 2311 tzset_unlocked(); 2312 result = posix2time_z(lclptr, t); 2313 rwlock_unlock(&lcl_lock); 2314 return result; 2315 } 2316 2317 #endif /* defined STD_INSPIRED */ 2318