localtime.c revision 1.56.2.1
1 /* $NetBSD: localtime.c,v 1.56.2.1 2011/06/23 14:18:37 cherry 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 8.9"; 12 #else 13 __RCSID("$NetBSD: localtime.c,v 1.56.2.1 2011/06/23 14:18:37 cherry 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 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 long 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 long 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, sizeof gmt), 132 (2 * (MY_TZNAME_MAX + 1)))]; 133 struct lsinfo lsis[TZ_MAX_LEAPS]; 134 }; 135 136 struct rule { 137 int r_type; /* type of rule--see below */ 138 int r_day; /* day number of rule */ 139 int r_week; /* week number of rule */ 140 int r_mon; /* month number of rule */ 141 long r_time; /* transition time of rule */ 142 }; 143 144 #define JULIAN_DAY 0 /* Jn - Julian day */ 145 #define DAY_OF_YEAR 1 /* n - day of year */ 146 #define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */ 147 148 typedef struct tm *(*subfun_t)(const timezone_t sp, const time_t *timep, 149 long offset, struct tm *tmp); 150 151 /* 152 ** Prototypes for static functions. 153 */ 154 155 static long detzcode(const char * codep); 156 static time_t detzcode64(const char * codep); 157 static int differ_by_repeat(time_t t1, time_t t0); 158 static const char * getzname(const char * strp); 159 static const char * getqzname(const char * strp, const int delim); 160 static const char * getnum(const char * strp, int * nump, int min, 161 int max); 162 static const char * getsecs(const char * strp, long * secsp); 163 static const char * getoffset(const char * strp, long * offsetp); 164 static const char * getrule(const char * strp, struct rule * rulep); 165 static void gmtload(timezone_t sp); 166 static struct tm * gmtsub(const timezone_t sp, const time_t *timep, 167 long offset, struct tm * tmp); 168 static struct tm * localsub(const timezone_t sp, const time_t *timep, 169 long offset, struct tm *tmp); 170 static int increment_overflow(int * number, int delta); 171 static int leaps_thru_end_of(int y); 172 static int long_increment_overflow(long * number, int delta); 173 static int long_normalize_overflow(long * tensptr, 174 int * unitsptr, int base); 175 static int normalize_overflow(int * tensptr, int * unitsptr, 176 int base); 177 static void settzname(void); 178 static time_t time1(const timezone_t sp, struct tm * const tmp, 179 subfun_t funcp, long offset); 180 static time_t time2(const timezone_t sp, struct tm * const tmp, 181 subfun_t funcp, 182 const long offset, int *const okayp); 183 static time_t time2sub(const timezone_t sp, struct tm * consttmp, 184 subfun_t funcp, const long offset, 185 int *const okayp, const int do_norm_secs); 186 static struct tm * timesub(const timezone_t sp, const time_t * timep, 187 long offset, struct tm * tmp); 188 static int tmcomp(const struct tm * atmp, 189 const struct tm * btmp); 190 static time_t transtime(time_t janfirst, int year, 191 const struct rule * rulep, long offset); 192 static int typesequiv(const timezone_t sp, int a, int b); 193 static int tzload(timezone_t sp, const char * name, 194 int doextend); 195 static int tzparse(timezone_t sp, const char * name, 196 int lastditch); 197 static void tzset_unlocked(void); 198 static void tzsetwall_unlocked(void); 199 static long leapcorr(const timezone_t sp, time_t * timep); 200 201 static timezone_t lclptr; 202 static timezone_t gmtptr; 203 204 #ifndef TZ_STRLEN_MAX 205 #define TZ_STRLEN_MAX 255 206 #endif /* !defined TZ_STRLEN_MAX */ 207 208 static char lcl_TZname[TZ_STRLEN_MAX + 1]; 209 static int lcl_is_set; 210 static int gmt_is_set; 211 212 #if !defined(__LIBC12_SOURCE__) 213 214 __aconst char * tzname[2] = { 215 (__aconst char *)__UNCONST(wildabbr), 216 (__aconst char *)__UNCONST(wildabbr) 217 }; 218 219 #else 220 221 extern __aconst char * tzname[2]; 222 223 #endif 224 225 #ifdef _REENTRANT 226 static rwlock_t lcl_lock = RWLOCK_INITIALIZER; 227 #endif 228 229 /* 230 ** Section 4.12.3 of X3.159-1989 requires that 231 ** Except for the strftime function, these functions [asctime, 232 ** ctime, gmtime, localtime] return values in one of two static 233 ** objects: a broken-down time structure and an array of char. 234 ** Thanks to Paul Eggert for noting this. 235 */ 236 237 static struct tm tm; 238 239 #ifdef USG_COMPAT 240 #if !defined(__LIBC12_SOURCE__) 241 long timezone = 0; 242 int daylight = 0; 243 #else 244 extern int daylight; 245 extern long timezone __RENAME(__timezone13); 246 #endif 247 #endif /* defined USG_COMPAT */ 248 249 #ifdef ALTZONE 250 time_t altzone = 0; 251 #endif /* defined ALTZONE */ 252 253 static long 254 detzcode(const char *const codep) 255 { 256 long result; 257 int i; 258 259 result = (codep[0] & 0x80) ? ~0L : 0; 260 for (i = 0; i < 4; ++i) 261 result = (result << 8) | (codep[i] & 0xff); 262 return result; 263 } 264 265 static time_t 266 detzcode64(const char *const codep) 267 { 268 time_t result; 269 int i; 270 271 result = (codep[0] & 0x80) ? -1 : 0; 272 for (i = 0; i < 8; ++i) 273 result = result * 256 + (codep[i] & 0xff); 274 return result; 275 } 276 277 const char * 278 tzgetname(const timezone_t sp, int isdst) 279 { 280 int i; 281 for (i = 0; i < sp->timecnt; ++i) { 282 const struct ttinfo *const ttisp = &sp->ttis[sp->types[i]]; 283 284 if (ttisp->tt_isdst == isdst) 285 return &sp->chars[ttisp->tt_abbrind]; 286 } 287 return NULL; 288 } 289 290 static void 291 settzname_z(timezone_t sp) 292 { 293 int i; 294 295 /* 296 ** Scrub the abbreviations. 297 ** First, replace bogus characters. 298 */ 299 for (i = 0; i < sp->charcnt; ++i) 300 if (strchr(TZ_ABBR_CHAR_SET, sp->chars[i]) == NULL) 301 sp->chars[i] = TZ_ABBR_ERR_CHAR; 302 /* 303 ** Second, truncate long abbreviations. 304 */ 305 for (i = 0; i < sp->typecnt; ++i) { 306 const struct ttinfo * const ttisp = &sp->ttis[i]; 307 char * cp = &sp->chars[ttisp->tt_abbrind]; 308 309 if (strlen(cp) > TZ_ABBR_MAX_LEN && 310 strcmp(cp, GRANDPARENTED) != 0) 311 *(cp + TZ_ABBR_MAX_LEN) = '\0'; 312 } 313 } 314 315 static void 316 settzname(void) 317 { 318 timezone_t const sp = lclptr; 319 int i; 320 321 tzname[0] = (__aconst char *)__UNCONST(wildabbr); 322 tzname[1] = (__aconst char *)__UNCONST(wildabbr); 323 #ifdef USG_COMPAT 324 daylight = 0; 325 timezone = 0; 326 #endif /* defined USG_COMPAT */ 327 #ifdef ALTZONE 328 altzone = 0; 329 #endif /* defined ALTZONE */ 330 if (sp == NULL) { 331 tzname[0] = tzname[1] = (__aconst char *)__UNCONST(gmt); 332 return; 333 } 334 for (i = 0; i < sp->typecnt; ++i) { 335 const struct ttinfo * const ttisp = &sp->ttis[i]; 336 337 tzname[ttisp->tt_isdst] = 338 &sp->chars[ttisp->tt_abbrind]; 339 #ifdef USG_COMPAT 340 if (ttisp->tt_isdst) 341 daylight = 1; 342 if (i == 0 || !ttisp->tt_isdst) 343 timezone = -(ttisp->tt_gmtoff); 344 #endif /* defined USG_COMPAT */ 345 #ifdef ALTZONE 346 if (i == 0 || ttisp->tt_isdst) 347 altzone = -(ttisp->tt_gmtoff); 348 #endif /* defined ALTZONE */ 349 } 350 /* 351 ** And to get the latest zone names into tzname. . . 352 */ 353 for (i = 0; i < sp->timecnt; ++i) { 354 register const struct ttinfo * const ttisp = 355 &sp->ttis[ 356 sp->types[i]]; 357 358 tzname[ttisp->tt_isdst] = 359 &sp->chars[ttisp->tt_abbrind]; 360 } 361 settzname_z(sp); 362 } 363 364 static int 365 differ_by_repeat(const time_t t1, const time_t t0) 366 { 367 /* CONSTCOND */ 368 if (TYPE_INTEGRAL(time_t) && 369 TYPE_BIT(time_t) - TYPE_SIGNED(time_t) < SECSPERREPEAT_BITS) 370 return 0; 371 return (int_fast64_t)t1 - (int_fast64_t)t0 == SECSPERREPEAT; 372 } 373 374 static int 375 tzload(timezone_t sp, const char *name, const int doextend) 376 { 377 const char * p; 378 int i; 379 int fid; 380 int stored; 381 int nread; 382 union { 383 struct tzhead tzhead; 384 char buf[2 * sizeof(struct tzhead) + 385 2 * sizeof *sp + 386 4 * TZ_MAX_TIMES]; 387 } u; 388 389 sp->goback = sp->goahead = FALSE; 390 if (name == NULL && (name = TZDEFAULT) == NULL) 391 return -1; 392 { 393 int doaccess; 394 /* 395 ** Section 4.9.1 of the C standard says that 396 ** "FILENAME_MAX expands to an integral constant expression 397 ** that is the size needed for an array of char large enough 398 ** to hold the longest file name string that the implementation 399 ** guarantees can be opened." 400 */ 401 char fullname[FILENAME_MAX + 1]; 402 403 if (name[0] == ':') 404 ++name; 405 doaccess = name[0] == '/'; 406 if (!doaccess) { 407 if ((p = TZDIR) == NULL) 408 return -1; 409 if ((strlen(p) + strlen(name) + 1) >= sizeof fullname) 410 return -1; 411 (void) strcpy(fullname, p); /* XXX strcpy is safe */ 412 (void) strcat(fullname, "/"); /* XXX strcat is safe */ 413 (void) strcat(fullname, name); /* XXX strcat is safe */ 414 /* 415 ** Set doaccess if '.' (as in "../") shows up in name. 416 */ 417 if (strchr(name, '.') != NULL) 418 doaccess = TRUE; 419 name = fullname; 420 } 421 if (doaccess && access(name, R_OK) != 0) 422 return -1; 423 /* 424 * XXX potential security problem here if user of a set-id 425 * program has set TZ (which is passed in as name) here, 426 * and uses a race condition trick to defeat the access(2) 427 * above. 428 */ 429 if ((fid = open(name, OPEN_MODE)) == -1) 430 return -1; 431 } 432 nread = read(fid, u.buf, sizeof u.buf); 433 if (close(fid) < 0 || nread <= 0) 434 return -1; 435 for (stored = 4; stored <= 8; stored *= 2) { 436 int ttisstdcnt; 437 int ttisgmtcnt; 438 439 ttisstdcnt = (int) detzcode(u.tzhead.tzh_ttisstdcnt); 440 ttisgmtcnt = (int) detzcode(u.tzhead.tzh_ttisgmtcnt); 441 sp->leapcnt = (int) detzcode(u.tzhead.tzh_leapcnt); 442 sp->timecnt = (int) detzcode(u.tzhead.tzh_timecnt); 443 sp->typecnt = (int) detzcode(u.tzhead.tzh_typecnt); 444 sp->charcnt = (int) detzcode(u.tzhead.tzh_charcnt); 445 p = u.tzhead.tzh_charcnt + sizeof u.tzhead.tzh_charcnt; 446 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS || 447 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES || 448 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES || 449 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS || 450 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) || 451 (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0)) 452 return -1; 453 if (nread - (p - u.buf) < 454 sp->timecnt * stored + /* ats */ 455 sp->timecnt + /* types */ 456 sp->typecnt * 6 + /* ttinfos */ 457 sp->charcnt + /* chars */ 458 sp->leapcnt * (stored + 4) + /* lsinfos */ 459 ttisstdcnt + /* ttisstds */ 460 ttisgmtcnt) /* ttisgmts */ 461 return -1; 462 for (i = 0; i < sp->timecnt; ++i) { 463 sp->ats[i] = (stored == 4) ? 464 detzcode(p) : detzcode64(p); 465 p += stored; 466 } 467 for (i = 0; i < sp->timecnt; ++i) { 468 sp->types[i] = (unsigned char) *p++; 469 if (sp->types[i] >= sp->typecnt) 470 return -1; 471 } 472 for (i = 0; i < sp->typecnt; ++i) { 473 struct ttinfo * ttisp; 474 475 ttisp = &sp->ttis[i]; 476 ttisp->tt_gmtoff = detzcode(p); 477 p += 4; 478 ttisp->tt_isdst = (unsigned char) *p++; 479 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1) 480 return -1; 481 ttisp->tt_abbrind = (unsigned char) *p++; 482 if (ttisp->tt_abbrind < 0 || 483 ttisp->tt_abbrind > sp->charcnt) 484 return -1; 485 } 486 for (i = 0; i < sp->charcnt; ++i) 487 sp->chars[i] = *p++; 488 sp->chars[i] = '\0'; /* ensure '\0' at end */ 489 for (i = 0; i < sp->leapcnt; ++i) { 490 struct lsinfo * lsisp; 491 492 lsisp = &sp->lsis[i]; 493 lsisp->ls_trans = (stored == 4) ? 494 detzcode(p) : detzcode64(p); 495 p += stored; 496 lsisp->ls_corr = detzcode(p); 497 p += 4; 498 } 499 for (i = 0; i < sp->typecnt; ++i) { 500 struct ttinfo * ttisp; 501 502 ttisp = &sp->ttis[i]; 503 if (ttisstdcnt == 0) 504 ttisp->tt_ttisstd = FALSE; 505 else { 506 ttisp->tt_ttisstd = *p++; 507 if (ttisp->tt_ttisstd != TRUE && 508 ttisp->tt_ttisstd != FALSE) 509 return -1; 510 } 511 } 512 for (i = 0; i < sp->typecnt; ++i) { 513 struct ttinfo * ttisp; 514 515 ttisp = &sp->ttis[i]; 516 if (ttisgmtcnt == 0) 517 ttisp->tt_ttisgmt = FALSE; 518 else { 519 ttisp->tt_ttisgmt = *p++; 520 if (ttisp->tt_ttisgmt != TRUE && 521 ttisp->tt_ttisgmt != FALSE) 522 return -1; 523 } 524 } 525 /* 526 ** Out-of-sort ats should mean we're running on a 527 ** signed time_t system but using a data file with 528 ** unsigned values (or vice versa). 529 */ 530 for (i = 0; i < sp->timecnt - 2; ++i) 531 if (sp->ats[i] > sp->ats[i + 1]) { 532 ++i; 533 /* CONSTCOND */ 534 if (TYPE_SIGNED(time_t)) { 535 /* 536 ** Ignore the end (easy). 537 */ 538 sp->timecnt = i; 539 } else { 540 /* 541 ** Ignore the beginning (harder). 542 */ 543 int j; 544 545 for (j = 0; j + i < sp->timecnt; ++j) { 546 sp->ats[j] = sp->ats[j + i]; 547 sp->types[j] = sp->types[j + i]; 548 } 549 sp->timecnt = j; 550 } 551 break; 552 } 553 /* 554 ** If this is an old file, we're done. 555 */ 556 if (u.tzhead.tzh_version[0] == '\0') 557 break; 558 nread -= p - u.buf; 559 for (i = 0; i < nread; ++i) 560 u.buf[i] = p[i]; 561 /* 562 ** If this is a narrow integer time_t system, we're done. 563 */ 564 if (stored >= (int) sizeof(time_t) 565 /* CONSTCOND */ 566 && TYPE_INTEGRAL(time_t)) 567 break; 568 } 569 if (doextend && nread > 2 && 570 u.buf[0] == '\n' && u.buf[nread - 1] == '\n' && 571 sp->typecnt + 2 <= TZ_MAX_TYPES) { 572 struct __state ts; 573 int result; 574 575 u.buf[nread - 1] = '\0'; 576 result = tzparse(&ts, &u.buf[1], FALSE); 577 if (result == 0 && ts.typecnt == 2 && 578 sp->charcnt + ts.charcnt <= TZ_MAX_CHARS) { 579 for (i = 0; i < 2; ++i) 580 ts.ttis[i].tt_abbrind += 581 sp->charcnt; 582 for (i = 0; i < ts.charcnt; ++i) 583 sp->chars[sp->charcnt++] = 584 ts.chars[i]; 585 i = 0; 586 while (i < ts.timecnt && 587 ts.ats[i] <= 588 sp->ats[sp->timecnt - 1]) 589 ++i; 590 while (i < ts.timecnt && 591 sp->timecnt < TZ_MAX_TIMES) { 592 sp->ats[sp->timecnt] = 593 ts.ats[i]; 594 sp->types[sp->timecnt] = 595 sp->typecnt + 596 ts.types[i]; 597 ++sp->timecnt; 598 ++i; 599 } 600 sp->ttis[sp->typecnt++] = ts.ttis[0]; 601 sp->ttis[sp->typecnt++] = ts.ttis[1]; 602 } 603 } 604 if (sp->timecnt > 1) { 605 for (i = 1; i < sp->timecnt; ++i) 606 if (typesequiv(sp, sp->types[i], sp->types[0]) && 607 differ_by_repeat(sp->ats[i], sp->ats[0])) { 608 sp->goback = TRUE; 609 break; 610 } 611 for (i = sp->timecnt - 2; i >= 0; --i) 612 if (typesequiv(sp, sp->types[sp->timecnt - 1], 613 sp->types[i]) && 614 differ_by_repeat(sp->ats[sp->timecnt - 1], 615 sp->ats[i])) { 616 sp->goahead = TRUE; 617 break; 618 } 619 } 620 return 0; 621 } 622 623 static int 624 typesequiv(const timezone_t sp, const int a, const int b) 625 { 626 int result; 627 628 if (sp == NULL || 629 a < 0 || a >= sp->typecnt || 630 b < 0 || b >= sp->typecnt) 631 result = FALSE; 632 else { 633 const struct ttinfo * ap = &sp->ttis[a]; 634 const struct ttinfo * bp = &sp->ttis[b]; 635 result = ap->tt_gmtoff == bp->tt_gmtoff && 636 ap->tt_isdst == bp->tt_isdst && 637 ap->tt_ttisstd == bp->tt_ttisstd && 638 ap->tt_ttisgmt == bp->tt_ttisgmt && 639 strcmp(&sp->chars[ap->tt_abbrind], 640 &sp->chars[bp->tt_abbrind]) == 0; 641 } 642 return result; 643 } 644 645 static const int mon_lengths[2][MONSPERYEAR] = { 646 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, 647 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } 648 }; 649 650 static const int year_lengths[2] = { 651 DAYSPERNYEAR, DAYSPERLYEAR 652 }; 653 654 /* 655 ** Given a pointer into a time zone string, scan until a character that is not 656 ** a valid character in a zone name is found. Return a pointer to that 657 ** character. 658 */ 659 660 static const char * 661 getzname(strp) 662 const char * strp; 663 { 664 char c; 665 666 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && 667 c != '+') 668 ++strp; 669 return strp; 670 } 671 672 /* 673 ** Given a pointer into an extended time zone string, scan until the ending 674 ** delimiter of the zone name is located. Return a pointer to the delimiter. 675 ** 676 ** As with getzname above, the legal character set is actually quite 677 ** restricted, with other characters producing undefined results. 678 ** We don't do any checking here; checking is done later in common-case code. 679 */ 680 681 static const char * 682 getqzname(const char *strp, const int delim) 683 { 684 int c; 685 686 while ((c = *strp) != '\0' && c != delim) 687 ++strp; 688 return strp; 689 } 690 691 /* 692 ** Given a pointer into a time zone string, extract a number from that string. 693 ** Check that the number is within a specified range; if it is not, return 694 ** NULL. 695 ** Otherwise, return a pointer to the first character not part of the number. 696 */ 697 698 static const char * 699 getnum(strp, nump, min, max) 700 const char * strp; 701 int * const nump; 702 const int min; 703 const int max; 704 { 705 char c; 706 int num; 707 708 if (strp == NULL || !is_digit(c = *strp)) { 709 errno = EINVAL; 710 return NULL; 711 } 712 num = 0; 713 do { 714 num = num * 10 + (c - '0'); 715 if (num > max) { 716 errno = EOVERFLOW; 717 return NULL; /* illegal value */ 718 } 719 c = *++strp; 720 } while (is_digit(c)); 721 if (num < min) { 722 errno = EINVAL; 723 return NULL; /* illegal value */ 724 } 725 *nump = num; 726 return strp; 727 } 728 729 /* 730 ** Given a pointer into a time zone string, extract a number of seconds, 731 ** in hh[:mm[:ss]] form, from the string. 732 ** If any error occurs, return NULL. 733 ** Otherwise, return a pointer to the first character not part of the number 734 ** of seconds. 735 */ 736 737 static const char * 738 getsecs(const char *strp, long *const secsp) 739 { 740 int num; 741 742 /* 743 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like 744 ** "M10.4.6/26", which does not conform to Posix, 745 ** but which specifies the equivalent of 746 ** ``02:00 on the first Sunday on or after 23 Oct''. 747 */ 748 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); 749 if (strp == NULL) 750 return NULL; 751 *secsp = num * (long) SECSPERHOUR; 752 if (*strp == ':') { 753 ++strp; 754 strp = getnum(strp, &num, 0, MINSPERHOUR - 1); 755 if (strp == NULL) 756 return NULL; 757 *secsp += num * SECSPERMIN; 758 if (*strp == ':') { 759 ++strp; 760 /* `SECSPERMIN' allows for leap seconds. */ 761 strp = getnum(strp, &num, 0, SECSPERMIN); 762 if (strp == NULL) 763 return NULL; 764 *secsp += num; 765 } 766 } 767 return strp; 768 } 769 770 /* 771 ** Given a pointer into a time zone string, extract an offset, in 772 ** [+-]hh[:mm[:ss]] form, from the string. 773 ** If any error occurs, return NULL. 774 ** Otherwise, return a pointer to the first character not part of the time. 775 */ 776 777 static const char * 778 getoffset(const char *strp, long *const offsetp) 779 { 780 int neg = 0; 781 782 if (*strp == '-') { 783 neg = 1; 784 ++strp; 785 } else if (*strp == '+') 786 ++strp; 787 strp = getsecs(strp, offsetp); 788 if (strp == NULL) 789 return NULL; /* illegal time */ 790 if (neg) 791 *offsetp = -*offsetp; 792 return strp; 793 } 794 795 /* 796 ** Given a pointer into a time zone string, extract a rule in the form 797 ** date[/time]. See POSIX section 8 for the format of "date" and "time". 798 ** If a valid rule is not found, return NULL. 799 ** Otherwise, return a pointer to the first character not part of the rule. 800 */ 801 802 static const char * 803 getrule(const char *strp, struct rule *const rulep) 804 { 805 if (*strp == 'J') { 806 /* 807 ** Julian day. 808 */ 809 rulep->r_type = JULIAN_DAY; 810 ++strp; 811 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); 812 } else if (*strp == 'M') { 813 /* 814 ** Month, week, day. 815 */ 816 rulep->r_type = MONTH_NTH_DAY_OF_WEEK; 817 ++strp; 818 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); 819 if (strp == NULL) 820 return NULL; 821 if (*strp++ != '.') 822 return NULL; 823 strp = getnum(strp, &rulep->r_week, 1, 5); 824 if (strp == NULL) 825 return NULL; 826 if (*strp++ != '.') 827 return NULL; 828 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); 829 } else if (is_digit(*strp)) { 830 /* 831 ** Day of year. 832 */ 833 rulep->r_type = DAY_OF_YEAR; 834 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); 835 } else return NULL; /* invalid format */ 836 if (strp == NULL) 837 return NULL; 838 if (*strp == '/') { 839 /* 840 ** Time specified. 841 */ 842 ++strp; 843 strp = getsecs(strp, &rulep->r_time); 844 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ 845 return strp; 846 } 847 848 /* 849 ** Given the Epoch-relative time of January 1, 00:00:00 UTC, in a year, the 850 ** year, a rule, and the offset from UTC at the time that rule takes effect, 851 ** calculate the Epoch-relative time that rule takes effect. 852 */ 853 854 static time_t 855 transtime(const time_t janfirst, const int year, const struct rule *const rulep, 856 const long offset) 857 { 858 int leapyear; 859 time_t value; 860 int i; 861 int d, m1, yy0, yy1, yy2, dow; 862 863 INITIALIZE(value); 864 leapyear = isleap(year); 865 switch (rulep->r_type) { 866 867 case JULIAN_DAY: 868 /* 869 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap 870 ** years. 871 ** In non-leap years, or if the day number is 59 or less, just 872 ** add SECSPERDAY times the day number-1 to the time of 873 ** January 1, midnight, to get the day. 874 */ 875 value = janfirst + (rulep->r_day - 1) * SECSPERDAY; 876 if (leapyear && rulep->r_day >= 60) 877 value += SECSPERDAY; 878 break; 879 880 case DAY_OF_YEAR: 881 /* 882 ** n - day of year. 883 ** Just add SECSPERDAY times the day number to the time of 884 ** January 1, midnight, to get the day. 885 */ 886 value = janfirst + rulep->r_day * SECSPERDAY; 887 break; 888 889 case MONTH_NTH_DAY_OF_WEEK: 890 /* 891 ** Mm.n.d - nth "dth day" of month m. 892 */ 893 value = janfirst; 894 for (i = 0; i < rulep->r_mon - 1; ++i) 895 value += mon_lengths[leapyear][i] * SECSPERDAY; 896 897 /* 898 ** Use Zeller's Congruence to get day-of-week of first day of 899 ** month. 900 */ 901 m1 = (rulep->r_mon + 9) % 12 + 1; 902 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; 903 yy1 = yy0 / 100; 904 yy2 = yy0 % 100; 905 dow = ((26 * m1 - 2) / 10 + 906 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; 907 if (dow < 0) 908 dow += DAYSPERWEEK; 909 910 /* 911 ** "dow" is the day-of-week of the first day of the month. Get 912 ** the day-of-month (zero-origin) of the first "dow" day of the 913 ** month. 914 */ 915 d = rulep->r_day - dow; 916 if (d < 0) 917 d += DAYSPERWEEK; 918 for (i = 1; i < rulep->r_week; ++i) { 919 if (d + DAYSPERWEEK >= 920 mon_lengths[leapyear][rulep->r_mon - 1]) 921 break; 922 d += DAYSPERWEEK; 923 } 924 925 /* 926 ** "d" is the day-of-month (zero-origin) of the day we want. 927 */ 928 value += d * SECSPERDAY; 929 break; 930 } 931 932 /* 933 ** "value" is the Epoch-relative time of 00:00:00 UTC on the day in 934 ** question. To get the Epoch-relative time of the specified local 935 ** time on that day, add the transition time and the current offset 936 ** from UTC. 937 */ 938 return value + rulep->r_time + offset; 939 } 940 941 /* 942 ** Given a POSIX section 8-style TZ string, fill in the rule tables as 943 ** appropriate. 944 */ 945 946 static int 947 tzparse(timezone_t sp, const char *name, const int lastditch) 948 { 949 const char * stdname; 950 const char * dstname; 951 size_t stdlen; 952 size_t dstlen; 953 long stdoffset; 954 long dstoffset; 955 time_t * atp; 956 unsigned char * typep; 957 char * cp; 958 int load_result; 959 960 INITIALIZE(dstname); 961 stdname = name; 962 if (lastditch) { 963 stdlen = strlen(name); /* length of standard zone name */ 964 name += stdlen; 965 if (stdlen >= sizeof sp->chars) 966 stdlen = (sizeof sp->chars) - 1; 967 stdoffset = 0; 968 } else { 969 if (*name == '<') { 970 name++; 971 stdname = name; 972 name = getqzname(name, '>'); 973 if (*name != '>') 974 return (-1); 975 stdlen = name - stdname; 976 name++; 977 } else { 978 name = getzname(name); 979 stdlen = name - stdname; 980 } 981 if (*name == '\0') 982 return -1; 983 name = getoffset(name, &stdoffset); 984 if (name == NULL) 985 return -1; 986 } 987 load_result = tzload(sp, TZDEFRULES, FALSE); 988 if (load_result != 0) 989 sp->leapcnt = 0; /* so, we're off a little */ 990 if (*name != '\0') { 991 if (*name == '<') { 992 dstname = ++name; 993 name = getqzname(name, '>'); 994 if (*name != '>') 995 return -1; 996 dstlen = name - dstname; 997 name++; 998 } else { 999 dstname = name; 1000 name = getzname(name); 1001 dstlen = name - dstname; /* length of DST zone name */ 1002 } 1003 if (*name != '\0' && *name != ',' && *name != ';') { 1004 name = getoffset(name, &dstoffset); 1005 if (name == NULL) 1006 return -1; 1007 } else dstoffset = stdoffset - SECSPERHOUR; 1008 if (*name == '\0' && load_result != 0) 1009 name = TZDEFRULESTRING; 1010 if (*name == ',' || *name == ';') { 1011 struct rule start; 1012 struct rule end; 1013 int year; 1014 time_t janfirst; 1015 time_t starttime; 1016 time_t endtime; 1017 1018 ++name; 1019 if ((name = getrule(name, &start)) == NULL) 1020 return -1; 1021 if (*name++ != ',') 1022 return -1; 1023 if ((name = getrule(name, &end)) == NULL) 1024 return -1; 1025 if (*name != '\0') 1026 return -1; 1027 sp->typecnt = 2; /* standard time and DST */ 1028 /* 1029 ** Two transitions per year, from EPOCH_YEAR forward. 1030 */ 1031 sp->ttis[0].tt_gmtoff = -dstoffset; 1032 sp->ttis[0].tt_isdst = 1; 1033 sp->ttis[0].tt_abbrind = stdlen + 1; 1034 sp->ttis[1].tt_gmtoff = -stdoffset; 1035 sp->ttis[1].tt_isdst = 0; 1036 sp->ttis[1].tt_abbrind = 0; 1037 atp = sp->ats; 1038 typep = sp->types; 1039 janfirst = 0; 1040 sp->timecnt = 0; 1041 for (year = EPOCH_YEAR; 1042 sp->timecnt + 2 <= TZ_MAX_TIMES; 1043 ++year) { 1044 time_t newfirst; 1045 1046 starttime = transtime(janfirst, year, &start, 1047 stdoffset); 1048 endtime = transtime(janfirst, year, &end, 1049 dstoffset); 1050 if (starttime > endtime) { 1051 *atp++ = endtime; 1052 *typep++ = 1; /* DST ends */ 1053 *atp++ = starttime; 1054 *typep++ = 0; /* DST begins */ 1055 } else { 1056 *atp++ = starttime; 1057 *typep++ = 0; /* DST begins */ 1058 *atp++ = endtime; 1059 *typep++ = 1; /* DST ends */ 1060 } 1061 sp->timecnt += 2; 1062 newfirst = janfirst; 1063 newfirst += year_lengths[isleap(year)] * 1064 SECSPERDAY; 1065 if (newfirst <= janfirst) 1066 break; 1067 janfirst = newfirst; 1068 } 1069 } else { 1070 long theirstdoffset; 1071 long theirdstoffset; 1072 long theiroffset; 1073 int isdst; 1074 int i; 1075 int j; 1076 1077 if (*name != '\0') 1078 return -1; 1079 /* 1080 ** Initial values of theirstdoffset 1081 */ 1082 theirstdoffset = 0; 1083 for (i = 0; i < sp->timecnt; ++i) { 1084 j = sp->types[i]; 1085 if (!sp->ttis[j].tt_isdst) { 1086 theirstdoffset = 1087 -sp->ttis[j].tt_gmtoff; 1088 break; 1089 } 1090 } 1091 theirdstoffset = 0; 1092 for (i = 0; i < sp->timecnt; ++i) { 1093 j = sp->types[i]; 1094 if (sp->ttis[j].tt_isdst) { 1095 theirdstoffset = 1096 -sp->ttis[j].tt_gmtoff; 1097 break; 1098 } 1099 } 1100 /* 1101 ** Initially we're assumed to be in standard time. 1102 */ 1103 isdst = FALSE; 1104 theiroffset = theirstdoffset; 1105 /* 1106 ** Now juggle transition times and types 1107 ** tracking offsets as you do. 1108 */ 1109 for (i = 0; i < sp->timecnt; ++i) { 1110 j = sp->types[i]; 1111 sp->types[i] = sp->ttis[j].tt_isdst; 1112 if (sp->ttis[j].tt_ttisgmt) { 1113 /* No adjustment to transition time */ 1114 } else { 1115 /* 1116 ** If summer time is in effect, and the 1117 ** transition time was not specified as 1118 ** standard time, add the summer time 1119 ** offset to the transition time; 1120 ** otherwise, add the standard time 1121 ** offset to the transition time. 1122 */ 1123 /* 1124 ** Transitions from DST to DDST 1125 ** will effectively disappear since 1126 ** POSIX provides for only one DST 1127 ** offset. 1128 */ 1129 if (isdst && !sp->ttis[j].tt_ttisstd) { 1130 sp->ats[i] += dstoffset - 1131 theirdstoffset; 1132 } else { 1133 sp->ats[i] += stdoffset - 1134 theirstdoffset; 1135 } 1136 } 1137 theiroffset = -sp->ttis[j].tt_gmtoff; 1138 if (!sp->ttis[j].tt_isdst) 1139 theirstdoffset = theiroffset; 1140 else theirdstoffset = theiroffset; 1141 } 1142 /* 1143 ** Finally, fill in ttis. 1144 ** ttisstd and ttisgmt need not be handled. 1145 */ 1146 sp->ttis[0].tt_gmtoff = -stdoffset; 1147 sp->ttis[0].tt_isdst = FALSE; 1148 sp->ttis[0].tt_abbrind = 0; 1149 sp->ttis[1].tt_gmtoff = -dstoffset; 1150 sp->ttis[1].tt_isdst = TRUE; 1151 sp->ttis[1].tt_abbrind = stdlen + 1; 1152 sp->typecnt = 2; 1153 } 1154 } else { 1155 dstlen = 0; 1156 sp->typecnt = 1; /* only standard time */ 1157 sp->timecnt = 0; 1158 sp->ttis[0].tt_gmtoff = -stdoffset; 1159 sp->ttis[0].tt_isdst = 0; 1160 sp->ttis[0].tt_abbrind = 0; 1161 } 1162 sp->charcnt = stdlen + 1; 1163 if (dstlen != 0) 1164 sp->charcnt += dstlen + 1; 1165 if ((size_t) sp->charcnt > sizeof sp->chars) 1166 return -1; 1167 cp = sp->chars; 1168 (void) strncpy(cp, stdname, stdlen); 1169 cp += stdlen; 1170 *cp++ = '\0'; 1171 if (dstlen != 0) { 1172 (void) strncpy(cp, dstname, dstlen); 1173 *(cp + dstlen) = '\0'; 1174 } 1175 return 0; 1176 } 1177 1178 static void 1179 gmtload(timezone_t sp) 1180 { 1181 if (tzload(sp, gmt, TRUE) != 0) 1182 (void) tzparse(sp, gmt, TRUE); 1183 } 1184 1185 timezone_t 1186 tzalloc(const char *name) 1187 { 1188 timezone_t sp = calloc(1, sizeof *sp); 1189 if (sp == NULL) 1190 return NULL; 1191 if (tzload(sp, name, TRUE) != 0) { 1192 free(sp); 1193 return NULL; 1194 } 1195 settzname_z(sp); 1196 return sp; 1197 } 1198 1199 void 1200 tzfree(const timezone_t sp) 1201 { 1202 free(sp); 1203 } 1204 1205 static void 1206 tzsetwall_unlocked(void) 1207 { 1208 if (lcl_is_set < 0) 1209 return; 1210 lcl_is_set = -1; 1211 1212 if (lclptr == NULL) { 1213 int saveerrno = errno; 1214 lclptr = calloc(1, sizeof *lclptr); 1215 errno = saveerrno; 1216 if (lclptr == NULL) { 1217 settzname(); /* all we can do */ 1218 return; 1219 } 1220 } 1221 if (tzload(lclptr, NULL, TRUE) != 0) 1222 gmtload(lclptr); 1223 settzname(); 1224 } 1225 1226 #ifndef STD_INSPIRED 1227 /* 1228 ** A non-static declaration of tzsetwall in a system header file 1229 ** may cause a warning about this upcoming static declaration... 1230 */ 1231 static 1232 #endif /* !defined STD_INSPIRED */ 1233 void 1234 tzsetwall(void) 1235 { 1236 rwlock_wrlock(&lcl_lock); 1237 tzsetwall_unlocked(); 1238 rwlock_unlock(&lcl_lock); 1239 } 1240 1241 #ifndef STD_INSPIRED 1242 /* 1243 ** A non-static declaration of tzsetwall in a system header file 1244 ** may cause a warning about this upcoming static declaration... 1245 */ 1246 static 1247 #endif /* !defined STD_INSPIRED */ 1248 void 1249 tzset_unlocked(void) 1250 { 1251 const char * name; 1252 int saveerrno; 1253 1254 saveerrno = errno; 1255 name = getenv("TZ"); 1256 errno = saveerrno; 1257 if (name == NULL) { 1258 tzsetwall_unlocked(); 1259 return; 1260 } 1261 1262 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) 1263 return; 1264 lcl_is_set = strlen(name) < sizeof lcl_TZname; 1265 if (lcl_is_set) 1266 (void)strlcpy(lcl_TZname, name, sizeof(lcl_TZname)); 1267 1268 if (lclptr == NULL) { 1269 saveerrno = errno; 1270 lclptr = calloc(1, sizeof *lclptr); 1271 errno = saveerrno; 1272 if (lclptr == NULL) { 1273 settzname(); /* all we can do */ 1274 return; 1275 } 1276 } 1277 if (*name == '\0') { 1278 /* 1279 ** User wants it fast rather than right. 1280 */ 1281 lclptr->leapcnt = 0; /* so, we're off a little */ 1282 lclptr->timecnt = 0; 1283 lclptr->typecnt = 0; 1284 lclptr->ttis[0].tt_isdst = 0; 1285 lclptr->ttis[0].tt_gmtoff = 0; 1286 lclptr->ttis[0].tt_abbrind = 0; 1287 (void) strlcpy(lclptr->chars, gmt, sizeof(lclptr->chars)); 1288 } else if (tzload(lclptr, name, TRUE) != 0) 1289 if (name[0] == ':' || tzparse(lclptr, name, FALSE) != 0) 1290 (void) gmtload(lclptr); 1291 settzname(); 1292 } 1293 1294 void 1295 tzset(void) 1296 { 1297 rwlock_wrlock(&lcl_lock); 1298 tzset_unlocked(); 1299 rwlock_unlock(&lcl_lock); 1300 } 1301 1302 /* 1303 ** The easy way to behave "as if no library function calls" localtime 1304 ** is to not call it--so we drop its guts into "localsub", which can be 1305 ** freely called. (And no, the PANS doesn't require the above behavior-- 1306 ** but it *is* desirable.) 1307 ** 1308 ** The unused offset argument is for the benefit of mktime variants. 1309 */ 1310 1311 /*ARGSUSED*/ 1312 static struct tm * 1313 localsub(const timezone_t sp, const time_t * const timep, const long offset, 1314 struct tm *const tmp) 1315 { 1316 const struct ttinfo * ttisp; 1317 int i; 1318 struct tm * result; 1319 const time_t t = *timep; 1320 1321 if ((sp->goback && t < sp->ats[0]) || 1322 (sp->goahead && t > sp->ats[sp->timecnt - 1])) { 1323 time_t newt = t; 1324 time_t seconds; 1325 time_t tcycles; 1326 int_fast64_t icycles; 1327 1328 if (t < sp->ats[0]) 1329 seconds = sp->ats[0] - t; 1330 else seconds = t - sp->ats[sp->timecnt - 1]; 1331 --seconds; 1332 tcycles = seconds / YEARSPERREPEAT / AVGSECSPERYEAR; 1333 ++tcycles; 1334 icycles = tcycles; 1335 if (tcycles - icycles >= 1 || icycles - tcycles >= 1) 1336 return NULL; 1337 seconds = (time_t) icycles; 1338 seconds *= YEARSPERREPEAT; 1339 seconds *= AVGSECSPERYEAR; 1340 if (t < sp->ats[0]) 1341 newt += seconds; 1342 else newt -= seconds; 1343 if (newt < sp->ats[0] || 1344 newt > sp->ats[sp->timecnt - 1]) 1345 return NULL; /* "cannot happen" */ 1346 result = localsub(sp, &newt, offset, tmp); 1347 if (result == tmp) { 1348 time_t newy; 1349 1350 newy = tmp->tm_year; 1351 if (t < sp->ats[0]) 1352 newy -= (time_t)icycles * YEARSPERREPEAT; 1353 else newy += (time_t)icycles * YEARSPERREPEAT; 1354 tmp->tm_year = (int)newy; 1355 if (tmp->tm_year != newy) 1356 return NULL; 1357 } 1358 return result; 1359 } 1360 if (sp->timecnt == 0 || t < sp->ats[0]) { 1361 i = 0; 1362 while (sp->ttis[i].tt_isdst) 1363 if (++i >= sp->typecnt) { 1364 i = 0; 1365 break; 1366 } 1367 } else { 1368 int lo = 1; 1369 int hi = sp->timecnt; 1370 1371 while (lo < hi) { 1372 int mid = (lo + hi) / 2; 1373 1374 if (t < sp->ats[mid]) 1375 hi = mid; 1376 else lo = mid + 1; 1377 } 1378 i = (int) sp->types[lo - 1]; 1379 } 1380 ttisp = &sp->ttis[i]; 1381 /* 1382 ** To get (wrong) behavior that's compatible with System V Release 2.0 1383 ** you'd replace the statement below with 1384 ** t += ttisp->tt_gmtoff; 1385 ** timesub(&t, 0L, sp, tmp); 1386 */ 1387 result = timesub(sp, &t, ttisp->tt_gmtoff, tmp); 1388 tmp->tm_isdst = ttisp->tt_isdst; 1389 if (sp == lclptr) 1390 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind]; 1391 #ifdef TM_ZONE 1392 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind]; 1393 #endif /* defined TM_ZONE */ 1394 return result; 1395 } 1396 1397 /* 1398 ** Re-entrant version of localtime. 1399 */ 1400 1401 struct tm * 1402 localtime_r(const time_t * __restrict timep, struct tm *tmp) 1403 { 1404 rwlock_rdlock(&lcl_lock); 1405 tzset_unlocked(); 1406 tmp = localtime_rz(lclptr, timep, tmp); 1407 rwlock_unlock(&lcl_lock); 1408 return tmp; 1409 } 1410 1411 struct tm * 1412 localtime(const time_t *const timep) 1413 { 1414 return localtime_r(timep, &tm); 1415 } 1416 1417 struct tm * 1418 localtime_rz(const timezone_t sp, const time_t * __restrict timep, struct tm *tmp) 1419 { 1420 if (sp == NULL) 1421 tmp = gmtsub(NULL, timep, 0L, tmp); 1422 else 1423 tmp = localsub(sp, timep, 0L, tmp); 1424 if (tmp == NULL) 1425 errno = EOVERFLOW; 1426 return tmp; 1427 } 1428 1429 /* 1430 ** gmtsub is to gmtime as localsub is to localtime. 1431 */ 1432 1433 static struct tm * 1434 gmtsub(const timezone_t sp, const time_t * const timep, const long offset, 1435 struct tm *const tmp) 1436 { 1437 struct tm * result; 1438 #ifdef _REENTRANT 1439 static mutex_t gmt_mutex = MUTEX_INITIALIZER; 1440 #endif 1441 1442 mutex_lock(&gmt_mutex); 1443 if (!gmt_is_set) { 1444 int saveerrno; 1445 gmt_is_set = TRUE; 1446 saveerrno = errno; 1447 gmtptr = calloc(1, sizeof *gmtptr); 1448 errno = saveerrno; 1449 if (gmtptr != NULL) 1450 gmtload(gmtptr); 1451 } 1452 mutex_unlock(&gmt_mutex); 1453 result = timesub(gmtptr, timep, offset, tmp); 1454 #ifdef TM_ZONE 1455 /* 1456 ** Could get fancy here and deliver something such as 1457 ** "UTC+xxxx" or "UTC-xxxx" if offset is non-zero, 1458 ** but this is no time for a treasure hunt. 1459 */ 1460 if (offset != 0) 1461 tmp->TM_ZONE = (__aconst char *)__UNCONST(wildabbr); 1462 else { 1463 if (gmtptr == NULL) 1464 tmp->TM_ZONE = (__aconst char *)__UNCONST(gmt); 1465 else tmp->TM_ZONE = gmtptr->chars; 1466 } 1467 #endif /* defined TM_ZONE */ 1468 return result; 1469 } 1470 1471 struct tm * 1472 gmtime(const time_t *const timep) 1473 { 1474 struct tm *tmp = gmtsub(NULL, timep, 0L, &tm); 1475 1476 if (tmp == NULL) 1477 errno = EOVERFLOW; 1478 1479 return tmp; 1480 } 1481 1482 /* 1483 ** Re-entrant version of gmtime. 1484 */ 1485 1486 struct tm * 1487 gmtime_r(const time_t * const timep, struct tm *tmp) 1488 { 1489 tmp = gmtsub(NULL, timep, 0L, tmp); 1490 1491 if (tmp == NULL) 1492 errno = EOVERFLOW; 1493 1494 return tmp; 1495 } 1496 1497 #ifdef STD_INSPIRED 1498 1499 struct tm * 1500 offtime(const time_t *const timep, long offset) 1501 { 1502 struct tm *tmp = gmtsub(NULL, timep, offset, &tm); 1503 1504 if (tmp == NULL) 1505 errno = EOVERFLOW; 1506 1507 return tmp; 1508 } 1509 1510 struct tm * 1511 offtime_r(const time_t *timep, long offset, struct tm *tmp) 1512 { 1513 tmp = gmtsub(NULL, timep, offset, tmp); 1514 1515 if (tmp == NULL) 1516 errno = EOVERFLOW; 1517 1518 return tmp; 1519 } 1520 1521 #endif /* defined STD_INSPIRED */ 1522 1523 /* 1524 ** Return the number of leap years through the end of the given year 1525 ** where, to make the math easy, the answer for year zero is defined as zero. 1526 */ 1527 1528 static int 1529 leaps_thru_end_of(const int y) 1530 { 1531 return (y >= 0) ? (y / 4 - y / 100 + y / 400) : 1532 -(leaps_thru_end_of(-(y + 1)) + 1); 1533 } 1534 1535 static struct tm * 1536 timesub(const timezone_t sp, const time_t *const timep, const long offset, 1537 struct tm *const tmp) 1538 { 1539 const struct lsinfo * lp; 1540 time_t tdays; 1541 int idays; /* unsigned would be so 2003 */ 1542 long rem; 1543 int y; 1544 const int * ip; 1545 long corr; 1546 int hit; 1547 int i; 1548 1549 corr = 0; 1550 hit = 0; 1551 i = (sp == NULL) ? 0 : sp->leapcnt; 1552 while (--i >= 0) { 1553 lp = &sp->lsis[i]; 1554 if (*timep >= lp->ls_trans) { 1555 if (*timep == lp->ls_trans) { 1556 hit = ((i == 0 && lp->ls_corr > 0) || 1557 lp->ls_corr > sp->lsis[i - 1].ls_corr); 1558 if (hit) 1559 while (i > 0 && 1560 sp->lsis[i].ls_trans == 1561 sp->lsis[i - 1].ls_trans + 1 && 1562 sp->lsis[i].ls_corr == 1563 sp->lsis[i - 1].ls_corr + 1) { 1564 ++hit; 1565 --i; 1566 } 1567 } 1568 corr = lp->ls_corr; 1569 break; 1570 } 1571 } 1572 y = EPOCH_YEAR; 1573 tdays = *timep / SECSPERDAY; 1574 rem = (long) (*timep - tdays * SECSPERDAY); 1575 while (tdays < 0 || tdays >= year_lengths[isleap(y)]) { 1576 int newy; 1577 time_t tdelta; 1578 int idelta; 1579 int leapdays; 1580 1581 tdelta = tdays / DAYSPERLYEAR; 1582 idelta = (int) tdelta; 1583 if (tdelta - idelta >= 1 || idelta - tdelta >= 1) 1584 return NULL; 1585 if (idelta == 0) 1586 idelta = (tdays < 0) ? -1 : 1; 1587 newy = y; 1588 if (increment_overflow(&newy, idelta)) 1589 return NULL; 1590 leapdays = leaps_thru_end_of(newy - 1) - 1591 leaps_thru_end_of(y - 1); 1592 tdays -= ((time_t) newy - y) * DAYSPERNYEAR; 1593 tdays -= leapdays; 1594 y = newy; 1595 } 1596 { 1597 long seconds; 1598 1599 seconds = tdays * SECSPERDAY + 0.5; 1600 tdays = seconds / SECSPERDAY; 1601 rem += (long) (seconds - tdays * SECSPERDAY); 1602 } 1603 /* 1604 ** Given the range, we can now fearlessly cast... 1605 */ 1606 idays = (int) tdays; 1607 rem += offset - corr; 1608 while (rem < 0) { 1609 rem += SECSPERDAY; 1610 --idays; 1611 } 1612 while (rem >= SECSPERDAY) { 1613 rem -= SECSPERDAY; 1614 ++idays; 1615 } 1616 while (idays < 0) { 1617 if (increment_overflow(&y, -1)) 1618 return NULL; 1619 idays += year_lengths[isleap(y)]; 1620 } 1621 while (idays >= year_lengths[isleap(y)]) { 1622 idays -= year_lengths[isleap(y)]; 1623 if (increment_overflow(&y, 1)) 1624 return NULL; 1625 } 1626 tmp->tm_year = y; 1627 if (increment_overflow(&tmp->tm_year, -TM_YEAR_BASE)) 1628 return NULL; 1629 tmp->tm_yday = idays; 1630 /* 1631 ** The "extra" mods below avoid overflow problems. 1632 */ 1633 tmp->tm_wday = EPOCH_WDAY + 1634 ((y - EPOCH_YEAR) % DAYSPERWEEK) * 1635 (DAYSPERNYEAR % DAYSPERWEEK) + 1636 leaps_thru_end_of(y - 1) - 1637 leaps_thru_end_of(EPOCH_YEAR - 1) + 1638 idays; 1639 tmp->tm_wday %= DAYSPERWEEK; 1640 if (tmp->tm_wday < 0) 1641 tmp->tm_wday += DAYSPERWEEK; 1642 tmp->tm_hour = (int) (rem / SECSPERHOUR); 1643 rem %= SECSPERHOUR; 1644 tmp->tm_min = (int) (rem / SECSPERMIN); 1645 /* 1646 ** A positive leap second requires a special 1647 ** representation. This uses "... ??:59:60" et seq. 1648 */ 1649 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit; 1650 ip = mon_lengths[isleap(y)]; 1651 for (tmp->tm_mon = 0; idays >= ip[tmp->tm_mon]; ++(tmp->tm_mon)) 1652 idays -= ip[tmp->tm_mon]; 1653 tmp->tm_mday = (int) (idays + 1); 1654 tmp->tm_isdst = 0; 1655 #ifdef TM_GMTOFF 1656 tmp->TM_GMTOFF = offset; 1657 #endif /* defined TM_GMTOFF */ 1658 return tmp; 1659 } 1660 1661 char * 1662 ctime(const time_t *const timep) 1663 { 1664 /* 1665 ** Section 4.12.3.2 of X3.159-1989 requires that 1666 ** The ctime function converts the calendar time pointed to by timer 1667 ** to local time in the form of a string. It is equivalent to 1668 ** asctime(localtime(timer)) 1669 */ 1670 struct tm *rtm = localtime(timep); 1671 if (rtm == NULL) 1672 return NULL; 1673 return asctime(rtm); 1674 } 1675 1676 char * 1677 ctime_r(const time_t *const timep, char *buf) 1678 { 1679 struct tm mytm, *rtm; 1680 1681 rtm = localtime_r(timep, &mytm); 1682 if (rtm == NULL) 1683 return NULL; 1684 return asctime_r(rtm, buf); 1685 } 1686 1687 char * 1688 ctime_rz(const timezone_t sp, const time_t * timep, char *buf) 1689 { 1690 struct tm mytm, *rtm; 1691 1692 rtm = localtime_rz(sp, timep, &mytm); 1693 if (rtm == NULL) 1694 return NULL; 1695 return asctime_r(rtm, buf); 1696 } 1697 1698 /* 1699 ** Adapted from code provided by Robert Elz, who writes: 1700 ** The "best" way to do mktime I think is based on an idea of Bob 1701 ** Kridle's (so its said...) from a long time ago. 1702 ** It does a binary search of the time_t space. Since time_t's are 1703 ** just 32 bits, its a max of 32 iterations (even at 64 bits it 1704 ** would still be very reasonable). 1705 */ 1706 1707 #ifndef WRONG 1708 #define WRONG ((time_t)-1) 1709 #endif /* !defined WRONG */ 1710 1711 /* 1712 ** Simplified normalize logic courtesy Paul Eggert. 1713 */ 1714 1715 static int 1716 increment_overflow(int *number, int delta) 1717 { 1718 int number0; 1719 1720 number0 = *number; 1721 if (delta < 0 ? number0 < INT_MIN - delta : INT_MAX - delta < number0) 1722 return 1; 1723 *number += delta; 1724 return 0; 1725 } 1726 1727 static int 1728 long_increment_overflow(long *number, int delta) 1729 { 1730 long number0; 1731 1732 number0 = *number; 1733 if (delta < 0 ? number0 < LONG_MIN - delta : LONG_MAX - delta < number0) 1734 return 1; 1735 *number += delta; 1736 return 0; 1737 } 1738 1739 static int 1740 normalize_overflow(int *const tensptr, int *const unitsptr, const int base) 1741 { 1742 int tensdelta; 1743 1744 tensdelta = (*unitsptr >= 0) ? 1745 (*unitsptr / base) : 1746 (-1 - (-1 - *unitsptr) / base); 1747 *unitsptr -= tensdelta * base; 1748 return increment_overflow(tensptr, tensdelta); 1749 } 1750 1751 static int 1752 long_normalize_overflow(long *const tensptr, int *const unitsptr, 1753 const int base) 1754 { 1755 int tensdelta; 1756 1757 tensdelta = (*unitsptr >= 0) ? 1758 (*unitsptr / base) : 1759 (-1 - (-1 - *unitsptr) / base); 1760 *unitsptr -= tensdelta * base; 1761 return long_increment_overflow(tensptr, tensdelta); 1762 } 1763 1764 static int 1765 tmcomp(const struct tm *const atmp, const struct tm *const btmp) 1766 { 1767 int result; 1768 1769 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 && 1770 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 && 1771 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && 1772 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && 1773 (result = (atmp->tm_min - btmp->tm_min)) == 0) 1774 result = atmp->tm_sec - btmp->tm_sec; 1775 return result; 1776 } 1777 1778 static time_t 1779 time2sub(const timezone_t sp, struct tm *const tmp, subfun_t funcp, 1780 const long offset, int *const okayp, const int do_norm_secs) 1781 { 1782 int dir; 1783 int i, j; 1784 int saved_seconds; 1785 long li; 1786 time_t lo; 1787 time_t hi; 1788 long y; 1789 time_t newt; 1790 time_t t; 1791 struct tm yourtm, mytm; 1792 1793 *okayp = FALSE; 1794 yourtm = *tmp; 1795 if (do_norm_secs) { 1796 if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec, 1797 SECSPERMIN)) 1798 return WRONG; 1799 } 1800 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) 1801 return WRONG; 1802 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) 1803 return WRONG; 1804 y = yourtm.tm_year; 1805 if (long_normalize_overflow(&y, &yourtm.tm_mon, MONSPERYEAR)) 1806 return WRONG; 1807 /* 1808 ** Turn y into an actual year number for now. 1809 ** It is converted back to an offset from TM_YEAR_BASE later. 1810 */ 1811 if (long_increment_overflow(&y, TM_YEAR_BASE)) 1812 return WRONG; 1813 while (yourtm.tm_mday <= 0) { 1814 if (long_increment_overflow(&y, -1)) 1815 return WRONG; 1816 li = y + (1 < yourtm.tm_mon); 1817 yourtm.tm_mday += year_lengths[isleap(li)]; 1818 } 1819 while (yourtm.tm_mday > DAYSPERLYEAR) { 1820 li = y + (1 < yourtm.tm_mon); 1821 yourtm.tm_mday -= year_lengths[isleap(li)]; 1822 if (long_increment_overflow(&y, 1)) 1823 return WRONG; 1824 } 1825 for ( ; ; ) { 1826 i = mon_lengths[isleap(y)][yourtm.tm_mon]; 1827 if (yourtm.tm_mday <= i) 1828 break; 1829 yourtm.tm_mday -= i; 1830 if (++yourtm.tm_mon >= MONSPERYEAR) { 1831 yourtm.tm_mon = 0; 1832 if (long_increment_overflow(&y, 1)) 1833 return WRONG; 1834 } 1835 } 1836 if (long_increment_overflow(&y, -TM_YEAR_BASE)) 1837 return WRONG; 1838 yourtm.tm_year = y; 1839 if (yourtm.tm_year != y) 1840 return WRONG; 1841 if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN) 1842 saved_seconds = 0; 1843 else if (y + TM_YEAR_BASE < EPOCH_YEAR) { 1844 /* 1845 ** We can't set tm_sec to 0, because that might push the 1846 ** time below the minimum representable time. 1847 ** Set tm_sec to 59 instead. 1848 ** This assumes that the minimum representable time is 1849 ** not in the same minute that a leap second was deleted from, 1850 ** which is a safer assumption than using 58 would be. 1851 */ 1852 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) 1853 return WRONG; 1854 saved_seconds = yourtm.tm_sec; 1855 yourtm.tm_sec = SECSPERMIN - 1; 1856 } else { 1857 saved_seconds = yourtm.tm_sec; 1858 yourtm.tm_sec = 0; 1859 } 1860 /* 1861 ** Do a binary search (this works whatever time_t's type is). 1862 */ 1863 /* LINTED constant */ 1864 if (!TYPE_SIGNED(time_t)) { 1865 lo = 0; 1866 hi = lo - 1; 1867 /* LINTED constant */ 1868 } else if (!TYPE_INTEGRAL(time_t)) { 1869 /* CONSTCOND */ 1870 if (sizeof(time_t) > sizeof(float)) 1871 /* LINTED assumed double */ 1872 hi = (time_t) DBL_MAX; 1873 /* LINTED assumed float */ 1874 else hi = (time_t) FLT_MAX; 1875 lo = -hi; 1876 } else { 1877 lo = 1; 1878 for (i = 0; i < (int) TYPE_BIT(time_t) - 1; ++i) 1879 lo *= 2; 1880 hi = -(lo + 1); 1881 } 1882 for ( ; ; ) { 1883 t = lo / 2 + hi / 2; 1884 if (t < lo) 1885 t = lo; 1886 else if (t > hi) 1887 t = hi; 1888 if ((*funcp)(sp, &t, offset, &mytm) == NULL) { 1889 /* 1890 ** Assume that t is too extreme to be represented in 1891 ** a struct tm; arrange things so that it is less 1892 ** extreme on the next pass. 1893 */ 1894 dir = (t > 0) ? 1 : -1; 1895 } else dir = tmcomp(&mytm, &yourtm); 1896 if (dir != 0) { 1897 if (t == lo) { 1898 ++t; 1899 if (t <= lo) 1900 return WRONG; 1901 ++lo; 1902 } else if (t == hi) { 1903 --t; 1904 if (t >= hi) 1905 return WRONG; 1906 --hi; 1907 } 1908 if (lo > hi) 1909 return WRONG; 1910 if (dir > 0) 1911 hi = t; 1912 else lo = t; 1913 continue; 1914 } 1915 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) 1916 break; 1917 /* 1918 ** Right time, wrong type. 1919 ** Hunt for right time, right type. 1920 ** It's okay to guess wrong since the guess 1921 ** gets checked. 1922 */ 1923 if (sp == NULL) 1924 return WRONG; 1925 for (i = sp->typecnt - 1; i >= 0; --i) { 1926 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) 1927 continue; 1928 for (j = sp->typecnt - 1; j >= 0; --j) { 1929 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) 1930 continue; 1931 newt = t + sp->ttis[j].tt_gmtoff - 1932 sp->ttis[i].tt_gmtoff; 1933 if ((*funcp)(sp, &newt, offset, &mytm) == NULL) 1934 continue; 1935 if (tmcomp(&mytm, &yourtm) != 0) 1936 continue; 1937 if (mytm.tm_isdst != yourtm.tm_isdst) 1938 continue; 1939 /* 1940 ** We have a match. 1941 */ 1942 t = newt; 1943 goto label; 1944 } 1945 } 1946 return WRONG; 1947 } 1948 label: 1949 newt = t + saved_seconds; 1950 if ((newt < t) != (saved_seconds < 0)) 1951 return WRONG; 1952 t = newt; 1953 if ((*funcp)(sp, &t, offset, tmp)) { 1954 *okayp = TRUE; 1955 return t; 1956 } else 1957 return WRONG; 1958 } 1959 1960 static time_t 1961 time2(const timezone_t sp, struct tm *const tmp, subfun_t funcp, 1962 const long offset, int *const okayp) 1963 { 1964 time_t t; 1965 1966 /* 1967 ** First try without normalization of seconds 1968 ** (in case tm_sec contains a value associated with a leap second). 1969 ** If that fails, try with normalization of seconds. 1970 */ 1971 t = time2sub(sp, tmp, funcp, offset, okayp, FALSE); 1972 return *okayp ? t : time2sub(sp, tmp, funcp, offset, okayp, TRUE); 1973 } 1974 1975 static time_t 1976 time1(const timezone_t sp, struct tm *const tmp, subfun_t funcp, 1977 long offset) 1978 { 1979 time_t t; 1980 int samei, otheri; 1981 int sameind, otherind; 1982 int i; 1983 int nseen; 1984 int seen[TZ_MAX_TYPES]; 1985 int types[TZ_MAX_TYPES]; 1986 int okay; 1987 1988 if (tmp->tm_isdst > 1) 1989 tmp->tm_isdst = 1; 1990 t = time2(sp, tmp, funcp, offset, &okay); 1991 #ifdef PCTS 1992 /* 1993 ** PCTS code courtesy Grant Sullivan. 1994 */ 1995 if (okay) 1996 return t; 1997 if (tmp->tm_isdst < 0) 1998 tmp->tm_isdst = 0; /* reset to std and try again */ 1999 #endif /* defined PCTS */ 2000 #ifndef PCTS 2001 if (okay || tmp->tm_isdst < 0) 2002 return t; 2003 #endif /* !defined PCTS */ 2004 /* 2005 ** We're supposed to assume that somebody took a time of one type 2006 ** and did some math on it that yielded a "struct tm" that's bad. 2007 ** We try to divine the type they started from and adjust to the 2008 ** type they need. 2009 */ 2010 if (sp == NULL) 2011 return WRONG; 2012 for (i = 0; i < sp->typecnt; ++i) 2013 seen[i] = FALSE; 2014 nseen = 0; 2015 for (i = sp->timecnt - 1; i >= 0; --i) 2016 if (!seen[sp->types[i]]) { 2017 seen[sp->types[i]] = TRUE; 2018 types[nseen++] = sp->types[i]; 2019 } 2020 for (sameind = 0; sameind < nseen; ++sameind) { 2021 samei = types[sameind]; 2022 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) 2023 continue; 2024 for (otherind = 0; otherind < nseen; ++otherind) { 2025 otheri = types[otherind]; 2026 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) 2027 continue; 2028 tmp->tm_sec += (int)(sp->ttis[otheri].tt_gmtoff - 2029 sp->ttis[samei].tt_gmtoff); 2030 tmp->tm_isdst = !tmp->tm_isdst; 2031 t = time2(sp, tmp, funcp, offset, &okay); 2032 if (okay) 2033 return t; 2034 tmp->tm_sec -= (int)(sp->ttis[otheri].tt_gmtoff - 2035 sp->ttis[samei].tt_gmtoff); 2036 tmp->tm_isdst = !tmp->tm_isdst; 2037 } 2038 } 2039 return WRONG; 2040 } 2041 2042 time_t 2043 mktime_z(const timezone_t sp, struct tm *tmp) 2044 { 2045 time_t t; 2046 if (sp == NULL) 2047 t = time1(NULL, tmp, gmtsub, 0L); 2048 else 2049 t = time1(sp, tmp, localsub, 0L); 2050 if (t == WRONG) 2051 errno = EOVERFLOW; 2052 return t; 2053 } 2054 2055 time_t 2056 mktime(struct tm * const tmp) 2057 { 2058 time_t result; 2059 2060 rwlock_wrlock(&lcl_lock); 2061 tzset_unlocked(); 2062 result = mktime_z(lclptr, tmp); 2063 rwlock_unlock(&lcl_lock); 2064 return result; 2065 } 2066 2067 #ifdef STD_INSPIRED 2068 2069 time_t 2070 timelocal_z(const timezone_t sp, struct tm *tmp) 2071 { 2072 if (tmp != NULL) 2073 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 2074 return mktime_z(sp, tmp); 2075 } 2076 2077 time_t 2078 timelocal(struct tm *const tmp) 2079 { 2080 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 2081 return mktime(tmp); 2082 } 2083 2084 time_t 2085 timegm(struct tm *const tmp) 2086 { 2087 time_t t; 2088 2089 tmp->tm_isdst = 0; 2090 t = time1(gmtptr, tmp, gmtsub, 0L); 2091 if (t == WRONG) 2092 errno = EOVERFLOW; 2093 return t; 2094 } 2095 2096 time_t 2097 timeoff(struct tm *const tmp, const long offset) 2098 { 2099 time_t t; 2100 2101 tmp->tm_isdst = 0; 2102 t = time1(gmtptr, tmp, gmtsub, offset); 2103 if (t == WRONG) 2104 errno = EOVERFLOW; 2105 return t; 2106 } 2107 2108 #endif /* defined STD_INSPIRED */ 2109 2110 #ifdef CMUCS 2111 2112 /* 2113 ** The following is supplied for compatibility with 2114 ** previous versions of the CMUCS runtime library. 2115 */ 2116 2117 long 2118 gtime(struct tm *const tmp) 2119 { 2120 const time_t t = mktime(tmp); 2121 2122 if (t == WRONG) 2123 return -1; 2124 return t; 2125 } 2126 2127 #endif /* defined CMUCS */ 2128 2129 /* 2130 ** XXX--is the below the right way to conditionalize?? 2131 */ 2132 2133 #ifdef STD_INSPIRED 2134 2135 /* 2136 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 2137 ** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which 2138 ** is not the case if we are accounting for leap seconds. 2139 ** So, we provide the following conversion routines for use 2140 ** when exchanging timestamps with POSIX conforming systems. 2141 */ 2142 2143 static long 2144 leapcorr(const timezone_t sp, time_t *timep) 2145 { 2146 struct lsinfo * lp; 2147 int i; 2148 2149 i = sp->leapcnt; 2150 while (--i >= 0) { 2151 lp = &sp->lsis[i]; 2152 if (*timep >= lp->ls_trans) 2153 return lp->ls_corr; 2154 } 2155 return 0; 2156 } 2157 2158 time_t 2159 time2posix_z(const timezone_t sp, time_t t) 2160 { 2161 return t - leapcorr(sp, &t); 2162 } 2163 2164 time_t 2165 time2posix(time_t t) 2166 { 2167 time_t result; 2168 rwlock_wrlock(&lcl_lock); 2169 tzset_unlocked(); 2170 result = t - leapcorr(lclptr, &t); 2171 rwlock_unlock(&lcl_lock); 2172 return (result); 2173 } 2174 2175 time_t 2176 posix2time_z(const timezone_t sp, time_t t) 2177 { 2178 time_t x; 2179 time_t y; 2180 2181 /* 2182 ** For a positive leap second hit, the result 2183 ** is not unique. For a negative leap second 2184 ** hit, the corresponding time doesn't exist, 2185 ** so we return an adjacent second. 2186 */ 2187 x = t + leapcorr(sp, &t); 2188 y = x - leapcorr(sp, &x); 2189 if (y < t) { 2190 do { 2191 x++; 2192 y = x - leapcorr(sp, &x); 2193 } while (y < t); 2194 if (t != y) { 2195 return x - 1; 2196 } 2197 } else if (y > t) { 2198 do { 2199 --x; 2200 y = x - leapcorr(sp, &x); 2201 } while (y > t); 2202 if (t != y) { 2203 return x + 1; 2204 } 2205 } 2206 return x; 2207 } 2208 2209 2210 2211 time_t 2212 posix2time(time_t t) 2213 { 2214 time_t result; 2215 2216 rwlock_wrlock(&lcl_lock); 2217 tzset_unlocked(); 2218 result = posix2time_z(lclptr, t); 2219 rwlock_unlock(&lcl_lock); 2220 return result; 2221 } 2222 2223 #endif /* defined STD_INSPIRED */ 2224
Indexes created Thu Oct 02 10:09:58 GMT 2025