localtime.c revision 1.63
1/* $NetBSD: localtime.c,v 1.63 2011/11/07 19:42:03 christos Exp $ */ 2 3/* 4** This file is in the public domain, so clarified as of 5** 1996-06-05 by Arthur David Olson. 6*/ 7 8#include <sys/cdefs.h> 9#if defined(LIBC_SCCS) && !defined(lint) 10#if 0 11static char elsieid[] = "@(#)localtime.c 8.17"; 12#else 13__RCSID("$NetBSD: localtime.c,v 1.63 2011/11/07 19:42:03 christos Exp $"); 14#endif 15#endif /* LIBC_SCCS and not lint */ 16 17/* 18** Leap second handling from Bradley White. 19** POSIX-style TZ environment variable handling from Guy Harris. 20*/ 21 22/*LINTLIBRARY*/ 23 24#include "namespace.h" 25#include "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 84static const char wildabbr[] = WILDABBR; 85 86static 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 99struct 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 107struct 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 121struct __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 136struct 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 148typedef 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 155static long detzcode(const char * codep); 156static time_t detzcode64(const char * codep); 157static int differ_by_repeat(time_t t1, time_t t0); 158static const char * getzname(const char * strp); 159static const char * getqzname(const char * strp, const int delim); 160static const char * getnum(const char * strp, int * nump, int min, 161 int max); 162static const char * getsecs(const char * strp, long * secsp); 163static const char * getoffset(const char * strp, long * offsetp); 164static const char * getrule(const char * strp, struct rule * rulep); 165static void gmtload(timezone_t sp); 166static struct tm * gmtsub(const timezone_t sp, const time_t *timep, 167 long offset, struct tm * tmp); 168static struct tm * localsub(const timezone_t sp, const time_t *timep, 169 long offset, struct tm *tmp); 170static int increment_overflow(int * number, int delta); 171static int leaps_thru_end_of(int y); 172static int long_increment_overflow(long * number, int delta); 173static int long_normalize_overflow(long * tensptr, 174 int * unitsptr, int base); 175static int normalize_overflow(int * tensptr, int * unitsptr, 176 int base); 177static void settzname(void); 178static time_t time1(const timezone_t sp, struct tm * const tmp, 179 subfun_t funcp, long offset); 180static time_t time2(const timezone_t sp, struct tm * const tmp, 181 subfun_t funcp, 182 const long offset, int *const okayp); 183static 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); 186static struct tm * timesub(const timezone_t sp, const time_t * timep, 187 long offset, struct tm * tmp); 188static int tmcomp(const struct tm * atmp, 189 const struct tm * btmp); 190static time_t transtime(time_t janfirst, int year, 191 const struct rule * rulep, long offset); 192static int typesequiv(const timezone_t sp, int a, int b); 193static int tzload(timezone_t sp, const char * name, 194 int doextend); 195static int tzparse(timezone_t sp, const char * name, 196 int lastditch); 197static void tzset_unlocked(void); 198static void tzsetwall_unlocked(void); 199static long leapcorr(const timezone_t sp, time_t * timep); 200 201static timezone_t lclptr; 202static timezone_t gmtptr; 203 204#ifndef TZ_STRLEN_MAX 205#define TZ_STRLEN_MAX 255 206#endif /* !defined TZ_STRLEN_MAX */ 207 208static char lcl_TZname[TZ_STRLEN_MAX + 1]; 209static int lcl_is_set; 210static 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 221extern __aconst char * tzname[2]; 222 223#endif 224 225#ifdef _REENTRANT 226static 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 237static struct tm tm; 238 239#ifdef USG_COMPAT 240#if !defined(__LIBC12_SOURCE__) 241long timezone = 0; 242int daylight = 0; 243#else 244extern int daylight; 245extern long timezone __RENAME(__timezone13); 246#endif 247#endif /* defined USG_COMPAT */ 248 249#ifdef ALTZONE 250time_t altzone = 0; 251#endif /* defined ALTZONE */ 252 253static long 254detzcode(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 265static time_t 266detzcode64(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 277const char * 278tzgetname(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 290static void 291settzname_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 315static void 316settzname(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 /* 335 ** And to get the latest zone names into tzname. . . 336 */ 337 for (i = 0; i < sp->typecnt; ++i) { 338 const struct ttinfo * const ttisp = &sp->ttis[i]; 339 340 tzname[ttisp->tt_isdst] = 341 &sp->chars[ttisp->tt_abbrind]; 342#ifdef USG_COMPAT 343 if (ttisp->tt_isdst) 344 daylight = 1; 345 if (!ttisp->tt_isdst) 346 timezone = -(ttisp->tt_gmtoff); 347#endif /* defined USG_COMPAT */ 348#ifdef ALTZONE 349 if (i == 0 || ttisp->tt_isdst) 350 altzone = -(ttisp->tt_gmtoff); 351#endif /* defined ALTZONE */ 352 } 353 settzname_z(sp); 354} 355 356static int 357differ_by_repeat(const time_t t1, const time_t t0) 358{ 359/* CONSTCOND */ 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 366static int 367tzload(timezone_t sp, const char *name, const int doextend) 368{ 369 const char * p; 370 int i; 371 int fid; 372 int stored; 373 int 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] = (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 = (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 - 2; ++i) 528 if (sp->ats[i] > sp->ats[i + 1]) { 529 ++i; 530/* CONSTCOND */ 531 if (TYPE_SIGNED(time_t)) { 532 /* 533 ** Ignore the end (easy). 534 */ 535 sp->timecnt = i; 536 } else { 537 /* 538 ** Ignore the beginning (harder). 539 */ 540 int j; 541 542 for (j = 0; j + i < sp->timecnt; ++j) { 543 sp->ats[j] = sp->ats[j + i]; 544 sp->types[j] = sp->types[j + i]; 545 } 546 sp->timecnt = j; 547 } 548 break; 549 } 550 /* 551 ** If this is an old file, we're done. 552 */ 553 if (up->tzhead.tzh_version[0] == '\0') 554 break; 555 nread -= p - up->buf; 556 for (i = 0; i < nread; ++i) 557 up->buf[i] = p[i]; 558 /* 559 ** If this is a narrow integer time_t system, we're done. 560 */ 561 if (stored >= (int) sizeof(time_t) 562/* CONSTCOND */ 563 && TYPE_INTEGRAL(time_t)) 564 break; 565 } 566 if (doextend && nread > 2 && 567 up->buf[0] == '\n' && up->buf[nread - 1] == '\n' && 568 sp->typecnt + 2 <= TZ_MAX_TYPES) { 569 struct __state ts; 570 int result; 571 572 up->buf[nread - 1] = '\0'; 573 result = tzparse(&ts, &up->buf[1], FALSE); 574 if (result == 0 && ts.typecnt == 2 && 575 sp->charcnt + ts.charcnt <= TZ_MAX_CHARS) { 576 for (i = 0; i < 2; ++i) 577 ts.ttis[i].tt_abbrind += 578 sp->charcnt; 579 for (i = 0; i < ts.charcnt; ++i) 580 sp->chars[sp->charcnt++] = 581 ts.chars[i]; 582 i = 0; 583 while (i < ts.timecnt && 584 ts.ats[i] <= 585 sp->ats[sp->timecnt - 1]) 586 ++i; 587 while (i < ts.timecnt && 588 sp->timecnt < TZ_MAX_TIMES) { 589 sp->ats[sp->timecnt] = 590 ts.ats[i]; 591 sp->types[sp->timecnt] = 592 sp->typecnt + 593 ts.types[i]; 594 ++sp->timecnt; 595 ++i; 596 } 597 sp->ttis[sp->typecnt++] = ts.ttis[0]; 598 sp->ttis[sp->typecnt++] = ts.ttis[1]; 599 } 600 } 601 if (sp->timecnt > 1) { 602 for (i = 1; i < sp->timecnt; ++i) 603 if (typesequiv(sp, sp->types[i], sp->types[0]) && 604 differ_by_repeat(sp->ats[i], sp->ats[0])) { 605 sp->goback = TRUE; 606 break; 607 } 608 for (i = sp->timecnt - 2; i >= 0; --i) 609 if (typesequiv(sp, sp->types[sp->timecnt - 1], 610 sp->types[i]) && 611 differ_by_repeat(sp->ats[sp->timecnt - 1], 612 sp->ats[i])) { 613 sp->goahead = TRUE; 614 break; 615 } 616 } 617 free(up); 618 return 0; 619oops: 620 free(up); 621 return -1; 622} 623 624static int 625typesequiv(const timezone_t sp, const int a, const int b) 626{ 627 int result; 628 629 if (sp == NULL || 630 a < 0 || a >= sp->typecnt || 631 b < 0 || b >= sp->typecnt) 632 result = FALSE; 633 else { 634 const struct ttinfo * ap = &sp->ttis[a]; 635 const struct ttinfo * bp = &sp->ttis[b]; 636 result = ap->tt_gmtoff == bp->tt_gmtoff && 637 ap->tt_isdst == bp->tt_isdst && 638 ap->tt_ttisstd == bp->tt_ttisstd && 639 ap->tt_ttisgmt == bp->tt_ttisgmt && 640 strcmp(&sp->chars[ap->tt_abbrind], 641 &sp->chars[bp->tt_abbrind]) == 0; 642 } 643 return result; 644} 645 646static const int mon_lengths[2][MONSPERYEAR] = { 647 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, 648 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } 649}; 650 651static const int year_lengths[2] = { 652 DAYSPERNYEAR, DAYSPERLYEAR 653}; 654 655/* 656** Given a pointer into a time zone string, scan until a character that is not 657** a valid character in a zone name is found. Return a pointer to that 658** character. 659*/ 660 661static const char * 662getzname(strp) 663const char * strp; 664{ 665 char c; 666 667 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && 668 c != '+') 669 ++strp; 670 return strp; 671} 672 673/* 674** Given a pointer into an extended time zone string, scan until the ending 675** delimiter of the zone name is located. Return a pointer to the delimiter. 676** 677** As with getzname above, the legal character set is actually quite 678** restricted, with other characters producing undefined results. 679** We don't do any checking here; checking is done later in common-case code. 680*/ 681 682static const char * 683getqzname(const char *strp, const int delim) 684{ 685 int c; 686 687 while ((c = *strp) != '\0' && c != delim) 688 ++strp; 689 return strp; 690} 691 692/* 693** Given a pointer into a time zone string, extract a number from that string. 694** Check that the number is within a specified range; if it is not, return 695** NULL. 696** Otherwise, return a pointer to the first character not part of the number. 697*/ 698 699static const char * 700getnum(strp, nump, min, max) 701const char * strp; 702int * const nump; 703const int min; 704const int max; 705{ 706 char c; 707 int num; 708 709 if (strp == NULL || !is_digit(c = *strp)) { 710 errno = EINVAL; 711 return NULL; 712 } 713 num = 0; 714 do { 715 num = num * 10 + (c - '0'); 716 if (num > max) { 717 errno = EOVERFLOW; 718 return NULL; /* illegal value */ 719 } 720 c = *++strp; 721 } while (is_digit(c)); 722 if (num < min) { 723 errno = EINVAL; 724 return NULL; /* illegal value */ 725 } 726 *nump = num; 727 return strp; 728} 729 730/* 731** Given a pointer into a time zone string, extract a number of seconds, 732** in hh[:mm[:ss]] form, from the string. 733** If any error occurs, return NULL. 734** Otherwise, return a pointer to the first character not part of the number 735** of seconds. 736*/ 737 738static const char * 739getsecs(const char *strp, long *const secsp) 740{ 741 int num; 742 743 /* 744 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like 745 ** "M10.4.6/26", which does not conform to Posix, 746 ** but which specifies the equivalent of 747 ** ``02:00 on the first Sunday on or after 23 Oct''. 748 */ 749 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); 750 if (strp == NULL) 751 return NULL; 752 *secsp = num * (long) SECSPERHOUR; 753 if (*strp == ':') { 754 ++strp; 755 strp = getnum(strp, &num, 0, MINSPERHOUR - 1); 756 if (strp == NULL) 757 return NULL; 758 *secsp += num * SECSPERMIN; 759 if (*strp == ':') { 760 ++strp; 761 /* `SECSPERMIN' allows for leap seconds. */ 762 strp = getnum(strp, &num, 0, SECSPERMIN); 763 if (strp == NULL) 764 return NULL; 765 *secsp += num; 766 } 767 } 768 return strp; 769} 770 771/* 772** Given a pointer into a time zone string, extract an offset, in 773** [+-]hh[:mm[:ss]] form, from the string. 774** If any error occurs, return NULL. 775** Otherwise, return a pointer to the first character not part of the time. 776*/ 777 778static const char * 779getoffset(const char *strp, long *const offsetp) 780{ 781 int neg = 0; 782 783 if (*strp == '-') { 784 neg = 1; 785 ++strp; 786 } else if (*strp == '+') 787 ++strp; 788 strp = getsecs(strp, offsetp); 789 if (strp == NULL) 790 return NULL; /* illegal time */ 791 if (neg) 792 *offsetp = -*offsetp; 793 return strp; 794} 795 796/* 797** Given a pointer into a time zone string, extract a rule in the form 798** date[/time]. See POSIX section 8 for the format of "date" and "time". 799** If a valid rule is not found, return NULL. 800** Otherwise, return a pointer to the first character not part of the rule. 801*/ 802 803static const char * 804getrule(const char *strp, struct rule *const rulep) 805{ 806 if (*strp == 'J') { 807 /* 808 ** Julian day. 809 */ 810 rulep->r_type = JULIAN_DAY; 811 ++strp; 812 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); 813 } else if (*strp == 'M') { 814 /* 815 ** Month, week, day. 816 */ 817 rulep->r_type = MONTH_NTH_DAY_OF_WEEK; 818 ++strp; 819 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); 820 if (strp == NULL) 821 return NULL; 822 if (*strp++ != '.') 823 return NULL; 824 strp = getnum(strp, &rulep->r_week, 1, 5); 825 if (strp == NULL) 826 return NULL; 827 if (*strp++ != '.') 828 return NULL; 829 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); 830 } else if (is_digit(*strp)) { 831 /* 832 ** Day of year. 833 */ 834 rulep->r_type = DAY_OF_YEAR; 835 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); 836 } else return NULL; /* invalid format */ 837 if (strp == NULL) 838 return NULL; 839 if (*strp == '/') { 840 /* 841 ** Time specified. 842 */ 843 ++strp; 844 strp = getsecs(strp, &rulep->r_time); 845 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ 846 return strp; 847} 848 849/* 850** Given the Epoch-relative time of January 1, 00:00:00 UTC, in a year, the 851** year, a rule, and the offset from UTC at the time that rule takes effect, 852** calculate the Epoch-relative time that rule takes effect. 853*/ 854 855static time_t 856transtime(const time_t janfirst, const int year, const struct rule *const rulep, 857 const long offset) 858{ 859 int leapyear; 860 time_t value; 861 int i; 862 int d, m1, yy0, yy1, yy2, dow; 863 864 INITIALIZE(value); 865 leapyear = isleap(year); 866 switch (rulep->r_type) { 867 868 case JULIAN_DAY: 869 /* 870 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap 871 ** years. 872 ** In non-leap years, or if the day number is 59 or less, just 873 ** add SECSPERDAY times the day number-1 to the time of 874 ** January 1, midnight, to get the day. 875 */ 876 value = janfirst + (rulep->r_day - 1) * SECSPERDAY; 877 if (leapyear && rulep->r_day >= 60) 878 value += SECSPERDAY; 879 break; 880 881 case DAY_OF_YEAR: 882 /* 883 ** n - day of year. 884 ** Just add SECSPERDAY times the day number to the time of 885 ** January 1, midnight, to get the day. 886 */ 887 value = janfirst + rulep->r_day * SECSPERDAY; 888 break; 889 890 case MONTH_NTH_DAY_OF_WEEK: 891 /* 892 ** Mm.n.d - nth "dth day" of month m. 893 */ 894 value = janfirst; 895 for (i = 0; i < rulep->r_mon - 1; ++i) 896 value += mon_lengths[leapyear][i] * SECSPERDAY; 897 898 /* 899 ** Use Zeller's Congruence to get day-of-week of first day of 900 ** month. 901 */ 902 m1 = (rulep->r_mon + 9) % 12 + 1; 903 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; 904 yy1 = yy0 / 100; 905 yy2 = yy0 % 100; 906 dow = ((26 * m1 - 2) / 10 + 907 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; 908 if (dow < 0) 909 dow += DAYSPERWEEK; 910 911 /* 912 ** "dow" is the day-of-week of the first day of the month. Get 913 ** the day-of-month (zero-origin) of the first "dow" day of the 914 ** month. 915 */ 916 d = rulep->r_day - dow; 917 if (d < 0) 918 d += DAYSPERWEEK; 919 for (i = 1; i < rulep->r_week; ++i) { 920 if (d + DAYSPERWEEK >= 921 mon_lengths[leapyear][rulep->r_mon - 1]) 922 break; 923 d += DAYSPERWEEK; 924 } 925 926 /* 927 ** "d" is the day-of-month (zero-origin) of the day we want. 928 */ 929 value += d * SECSPERDAY; 930 break; 931 } 932 933 /* 934 ** "value" is the Epoch-relative time of 00:00:00 UTC on the day in 935 ** question. To get the Epoch-relative time of the specified local 936 ** time on that day, add the transition time and the current offset 937 ** from UTC. 938 */ 939 return value + rulep->r_time + offset; 940} 941 942/* 943** Given a POSIX section 8-style TZ string, fill in the rule tables as 944** appropriate. 945*/ 946 947static int 948tzparse(timezone_t sp, const char *name, const int lastditch) 949{ 950 const char * stdname; 951 const char * dstname; 952 size_t stdlen; 953 size_t dstlen; 954 long stdoffset; 955 long dstoffset; 956 time_t * atp; 957 unsigned char * typep; 958 char * cp; 959 int load_result; 960 961 INITIALIZE(dstname); 962 stdname = name; 963 if (lastditch) { 964 stdlen = strlen(name); /* length of standard zone name */ 965 name += stdlen; 966 if (stdlen >= sizeof sp->chars) 967 stdlen = (sizeof sp->chars) - 1; 968 stdoffset = 0; 969 } else { 970 if (*name == '<') { 971 name++; 972 stdname = name; 973 name = getqzname(name, '>'); 974 if (*name != '>') 975 return (-1); 976 stdlen = name - stdname; 977 name++; 978 } else { 979 name = getzname(name); 980 stdlen = name - stdname; 981 } 982 if (*name == '\0') 983 return -1; 984 name = getoffset(name, &stdoffset); 985 if (name == NULL) 986 return -1; 987 } 988 load_result = tzload(sp, TZDEFRULES, FALSE); 989 if (load_result != 0) 990 sp->leapcnt = 0; /* so, we're off a little */ 991 if (*name != '\0') { 992 if (*name == '<') { 993 dstname = ++name; 994 name = getqzname(name, '>'); 995 if (*name != '>') 996 return -1; 997 dstlen = name - dstname; 998 name++; 999 } else { 1000 dstname = name; 1001 name = getzname(name); 1002 dstlen = name - dstname; /* length of DST zone name */ 1003 } 1004 if (*name != '\0' && *name != ',' && *name != ';') { 1005 name = getoffset(name, &dstoffset); 1006 if (name == NULL) 1007 return -1; 1008 } else dstoffset = stdoffset - SECSPERHOUR; 1009 if (*name == '\0' && load_result != 0) 1010 name = TZDEFRULESTRING; 1011 if (*name == ',' || *name == ';') { 1012 struct rule start; 1013 struct rule end; 1014 int year; 1015 time_t janfirst; 1016 time_t starttime; 1017 time_t endtime; 1018 1019 ++name; 1020 if ((name = getrule(name, &start)) == NULL) 1021 return -1; 1022 if (*name++ != ',') 1023 return -1; 1024 if ((name = getrule(name, &end)) == NULL) 1025 return -1; 1026 if (*name != '\0') 1027 return -1; 1028 sp->typecnt = 2; /* standard time and DST */ 1029 /* 1030 ** Two transitions per year, from EPOCH_YEAR forward. 1031 */ 1032 memset(sp->ttis, 0, sizeof(sp->ttis)); 1033 sp->ttis[0].tt_gmtoff = -dstoffset; 1034 sp->ttis[0].tt_isdst = 1; 1035 sp->ttis[0].tt_abbrind = stdlen + 1; 1036 sp->ttis[1].tt_gmtoff = -stdoffset; 1037 sp->ttis[1].tt_isdst = 0; 1038 sp->ttis[1].tt_abbrind = 0; 1039 atp = sp->ats; 1040 typep = sp->types; 1041 janfirst = 0; 1042 sp->timecnt = 0; 1043 for (year = EPOCH_YEAR; 1044 sp->timecnt + 2 <= TZ_MAX_TIMES; 1045 ++year) { 1046 time_t newfirst; 1047 1048 starttime = transtime(janfirst, year, &start, 1049 stdoffset); 1050 endtime = transtime(janfirst, year, &end, 1051 dstoffset); 1052 if (starttime > endtime) { 1053 *atp++ = endtime; 1054 *typep++ = 1; /* DST ends */ 1055 *atp++ = starttime; 1056 *typep++ = 0; /* DST begins */ 1057 } else { 1058 *atp++ = starttime; 1059 *typep++ = 0; /* DST begins */ 1060 *atp++ = endtime; 1061 *typep++ = 1; /* DST ends */ 1062 } 1063 sp->timecnt += 2; 1064 newfirst = janfirst; 1065 newfirst += year_lengths[isleap(year)] * 1066 SECSPERDAY; 1067 if (newfirst <= janfirst) 1068 break; 1069 janfirst = newfirst; 1070 } 1071 } else { 1072 long theirstdoffset; 1073 long theirdstoffset; 1074 long theiroffset; 1075 int isdst; 1076 int i; 1077 int j; 1078 1079 if (*name != '\0') 1080 return -1; 1081 /* 1082 ** Initial values of theirstdoffset 1083 */ 1084 theirstdoffset = 0; 1085 for (i = 0; i < sp->timecnt; ++i) { 1086 j = sp->types[i]; 1087 if (!sp->ttis[j].tt_isdst) { 1088 theirstdoffset = 1089 -sp->ttis[j].tt_gmtoff; 1090 break; 1091 } 1092 } 1093 theirdstoffset = 0; 1094 for (i = 0; i < sp->timecnt; ++i) { 1095 j = sp->types[i]; 1096 if (sp->ttis[j].tt_isdst) { 1097 theirdstoffset = 1098 -sp->ttis[j].tt_gmtoff; 1099 break; 1100 } 1101 } 1102 /* 1103 ** Initially we're assumed to be in standard time. 1104 */ 1105 isdst = FALSE; 1106 theiroffset = theirstdoffset; 1107 /* 1108 ** Now juggle transition times and types 1109 ** tracking offsets as you do. 1110 */ 1111 for (i = 0; i < sp->timecnt; ++i) { 1112 j = sp->types[i]; 1113 sp->types[i] = sp->ttis[j].tt_isdst; 1114 if (sp->ttis[j].tt_ttisgmt) { 1115 /* No adjustment to transition time */ 1116 } else { 1117 /* 1118 ** If summer time is in effect, and the 1119 ** transition time was not specified as 1120 ** standard time, add the summer time 1121 ** offset to the transition time; 1122 ** otherwise, add the standard time 1123 ** offset to the transition time. 1124 */ 1125 /* 1126 ** Transitions from DST to DDST 1127 ** will effectively disappear since 1128 ** POSIX provides for only one DST 1129 ** offset. 1130 */ 1131 if (isdst && !sp->ttis[j].tt_ttisstd) { 1132 sp->ats[i] += dstoffset - 1133 theirdstoffset; 1134 } else { 1135 sp->ats[i] += stdoffset - 1136 theirstdoffset; 1137 } 1138 } 1139 theiroffset = -sp->ttis[j].tt_gmtoff; 1140 if (!sp->ttis[j].tt_isdst) 1141 theirstdoffset = theiroffset; 1142 else theirdstoffset = theiroffset; 1143 } 1144 /* 1145 ** Finally, fill in ttis. 1146 */ 1147 memset(sp->ttis, 0, sizeof(sp->ttis)); 1148 sp->ttis[0].tt_gmtoff = -stdoffset; 1149 sp->ttis[0].tt_isdst = FALSE; 1150 sp->ttis[0].tt_abbrind = 0; 1151 sp->ttis[1].tt_gmtoff = -dstoffset; 1152 sp->ttis[1].tt_isdst = TRUE; 1153 sp->ttis[1].tt_abbrind = stdlen + 1; 1154 sp->typecnt = 2; 1155 } 1156 } else { 1157 dstlen = 0; 1158 sp->typecnt = 1; /* only standard time */ 1159 sp->timecnt = 0; 1160 memset(sp->ttis, 0, sizeof(sp->ttis)); 1161 sp->ttis[0].tt_gmtoff = -stdoffset; 1162 sp->ttis[0].tt_isdst = 0; 1163 sp->ttis[0].tt_abbrind = 0; 1164 } 1165 sp->charcnt = stdlen + 1; 1166 if (dstlen != 0) 1167 sp->charcnt += dstlen + 1; 1168 if ((size_t) sp->charcnt > sizeof sp->chars) 1169 return -1; 1170 cp = sp->chars; 1171 (void) strncpy(cp, stdname, stdlen); 1172 cp += stdlen; 1173 *cp++ = '\0'; 1174 if (dstlen != 0) { 1175 (void) strncpy(cp, dstname, dstlen); 1176 *(cp + dstlen) = '\0'; 1177 } 1178 return 0; 1179} 1180 1181static void 1182gmtload(timezone_t sp) 1183{ 1184 if (tzload(sp, gmt, TRUE) != 0) 1185 (void) tzparse(sp, gmt, TRUE); 1186} 1187 1188timezone_t 1189tzalloc(const char *name) 1190{ 1191 timezone_t sp = calloc(1, sizeof *sp); 1192 if (sp == NULL) 1193 return NULL; 1194 if (tzload(sp, name, TRUE) != 0) { 1195 free(sp); 1196 return NULL; 1197 } 1198 settzname_z(sp); 1199 return sp; 1200} 1201 1202void 1203tzfree(const timezone_t sp) 1204{ 1205 free(sp); 1206} 1207 1208static void 1209tzsetwall_unlocked(void) 1210{ 1211 if (lcl_is_set < 0) 1212 return; 1213 lcl_is_set = -1; 1214 1215 if (lclptr == NULL) { 1216 int saveerrno = errno; 1217 lclptr = calloc(1, sizeof *lclptr); 1218 errno = saveerrno; 1219 if (lclptr == NULL) { 1220 settzname(); /* all we can do */ 1221 return; 1222 } 1223 } 1224 if (tzload(lclptr, NULL, TRUE) != 0) 1225 gmtload(lclptr); 1226 settzname(); 1227} 1228 1229#ifndef STD_INSPIRED 1230/* 1231** A non-static declaration of tzsetwall in a system header file 1232** may cause a warning about this upcoming static declaration... 1233*/ 1234static 1235#endif /* !defined STD_INSPIRED */ 1236void 1237tzsetwall(void) 1238{ 1239 rwlock_wrlock(&lcl_lock); 1240 tzsetwall_unlocked(); 1241 rwlock_unlock(&lcl_lock); 1242} 1243 1244#ifndef STD_INSPIRED 1245/* 1246** A non-static declaration of tzsetwall in a system header file 1247** may cause a warning about this upcoming static declaration... 1248*/ 1249static 1250#endif /* !defined STD_INSPIRED */ 1251void 1252tzset_unlocked(void) 1253{ 1254 const char * name; 1255 int saveerrno; 1256 1257 saveerrno = errno; 1258 name = getenv("TZ"); 1259 errno = saveerrno; 1260 if (name == NULL) { 1261 tzsetwall_unlocked(); 1262 return; 1263 } 1264 1265 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) 1266 return; 1267 lcl_is_set = strlen(name) < sizeof lcl_TZname; 1268 if (lcl_is_set) 1269 (void)strlcpy(lcl_TZname, name, sizeof(lcl_TZname)); 1270 1271 if (lclptr == NULL) { 1272 saveerrno = errno; 1273 lclptr = calloc(1, sizeof *lclptr); 1274 errno = saveerrno; 1275 if (lclptr == NULL) { 1276 settzname(); /* all we can do */ 1277 return; 1278 } 1279 } 1280 if (*name == '\0') { 1281 /* 1282 ** User wants it fast rather than right. 1283 */ 1284 lclptr->leapcnt = 0; /* so, we're off a little */ 1285 lclptr->timecnt = 0; 1286 lclptr->typecnt = 0; 1287 lclptr->ttis[0].tt_isdst = 0; 1288 lclptr->ttis[0].tt_gmtoff = 0; 1289 lclptr->ttis[0].tt_abbrind = 0; 1290 (void) strlcpy(lclptr->chars, gmt, sizeof(lclptr->chars)); 1291 } else if (tzload(lclptr, name, TRUE) != 0) 1292 if (name[0] == ':' || tzparse(lclptr, name, FALSE) != 0) 1293 (void) gmtload(lclptr); 1294 settzname(); 1295} 1296 1297void 1298tzset(void) 1299{ 1300 rwlock_wrlock(&lcl_lock); 1301 tzset_unlocked(); 1302 rwlock_unlock(&lcl_lock); 1303} 1304 1305/* 1306** The easy way to behave "as if no library function calls" localtime 1307** is to not call it--so we drop its guts into "localsub", which can be 1308** freely called. (And no, the PANS doesn't require the above behavior-- 1309** but it *is* desirable.) 1310** 1311** The unused offset argument is for the benefit of mktime variants. 1312*/ 1313 1314/*ARGSUSED*/ 1315static struct tm * 1316localsub(const timezone_t sp, const time_t * const timep, const long offset, 1317 struct tm *const tmp) 1318{ 1319 const struct ttinfo * ttisp; 1320 int i; 1321 struct tm * result; 1322 const time_t t = *timep; 1323 1324 if ((sp->goback && t < sp->ats[0]) || 1325 (sp->goahead && t > sp->ats[sp->timecnt - 1])) { 1326 time_t newt = t; 1327 time_t seconds; 1328 time_t tcycles; 1329 int_fast64_t icycles; 1330 1331 if (t < sp->ats[0]) 1332 seconds = sp->ats[0] - t; 1333 else seconds = t - sp->ats[sp->timecnt - 1]; 1334 --seconds; 1335 tcycles = seconds / YEARSPERREPEAT / AVGSECSPERYEAR; 1336 ++tcycles; 1337 icycles = tcycles; 1338 if (tcycles - icycles >= 1 || icycles - tcycles >= 1) 1339 return NULL; 1340 seconds = (time_t) icycles; 1341 seconds *= YEARSPERREPEAT; 1342 seconds *= AVGSECSPERYEAR; 1343 if (t < sp->ats[0]) 1344 newt += seconds; 1345 else newt -= seconds; 1346 if (newt < sp->ats[0] || 1347 newt > sp->ats[sp->timecnt - 1]) 1348 return NULL; /* "cannot happen" */ 1349 result = localsub(sp, &newt, offset, tmp); 1350 if (result == tmp) { 1351 time_t newy; 1352 1353 newy = tmp->tm_year; 1354 if (t < sp->ats[0]) 1355 newy -= (time_t)icycles * YEARSPERREPEAT; 1356 else newy += (time_t)icycles * YEARSPERREPEAT; 1357 tmp->tm_year = (int)newy; 1358 if (tmp->tm_year != newy) 1359 return NULL; 1360 } 1361 return result; 1362 } 1363 if (sp->timecnt == 0 || t < sp->ats[0]) { 1364 i = 0; 1365 while (sp->ttis[i].tt_isdst) 1366 if (++i >= sp->typecnt) { 1367 i = 0; 1368 break; 1369 } 1370 } else { 1371 int lo = 1; 1372 int hi = sp->timecnt; 1373 1374 while (lo < hi) { 1375 int mid = (lo + hi) / 2; 1376 1377 if (t < sp->ats[mid]) 1378 hi = mid; 1379 else lo = mid + 1; 1380 } 1381 i = (int) sp->types[lo - 1]; 1382 } 1383 ttisp = &sp->ttis[i]; 1384 /* 1385 ** To get (wrong) behavior that's compatible with System V Release 2.0 1386 ** you'd replace the statement below with 1387 ** t += ttisp->tt_gmtoff; 1388 ** timesub(&t, 0L, sp, tmp); 1389 */ 1390 result = timesub(sp, &t, ttisp->tt_gmtoff, tmp); 1391 tmp->tm_isdst = ttisp->tt_isdst; 1392 if (sp == lclptr) 1393 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind]; 1394#ifdef TM_ZONE 1395 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind]; 1396#endif /* defined TM_ZONE */ 1397 return result; 1398} 1399 1400/* 1401** Re-entrant version of localtime. 1402*/ 1403 1404struct tm * 1405localtime_r(const time_t * __restrict timep, struct tm *tmp) 1406{ 1407 rwlock_rdlock(&lcl_lock); 1408 tzset_unlocked(); 1409 tmp = localtime_rz(lclptr, timep, tmp); 1410 rwlock_unlock(&lcl_lock); 1411 return tmp; 1412} 1413 1414struct tm * 1415localtime(const time_t *const timep) 1416{ 1417 return localtime_r(timep, &tm); 1418} 1419 1420struct tm * 1421localtime_rz(const timezone_t sp, const time_t * __restrict timep, struct tm *tmp) 1422{ 1423 if (sp == NULL) 1424 tmp = gmtsub(NULL, timep, 0L, tmp); 1425 else 1426 tmp = localsub(sp, timep, 0L, tmp); 1427 if (tmp == NULL) 1428 errno = EOVERFLOW; 1429 return tmp; 1430} 1431 1432/* 1433** gmtsub is to gmtime as localsub is to localtime. 1434*/ 1435 1436static struct tm * 1437gmtsub(const timezone_t sp, const time_t * const timep, const long offset, 1438 struct tm *const tmp) 1439{ 1440 struct tm * result; 1441#ifdef _REENTRANT 1442 static mutex_t gmt_mutex = MUTEX_INITIALIZER; 1443#endif 1444 1445 mutex_lock(&gmt_mutex); 1446 if (!gmt_is_set) { 1447 int saveerrno; 1448 gmt_is_set = TRUE; 1449 saveerrno = errno; 1450 gmtptr = calloc(1, sizeof *gmtptr); 1451 errno = saveerrno; 1452 if (gmtptr != NULL) 1453 gmtload(gmtptr); 1454 } 1455 mutex_unlock(&gmt_mutex); 1456 result = timesub(gmtptr, timep, offset, tmp); 1457#ifdef TM_ZONE 1458 /* 1459 ** Could get fancy here and deliver something such as 1460 ** "UTC+xxxx" or "UTC-xxxx" if offset is non-zero, 1461 ** but this is no time for a treasure hunt. 1462 */ 1463 if (offset != 0) 1464 tmp->TM_ZONE = (__aconst char *)__UNCONST(wildabbr); 1465 else { 1466 if (gmtptr == NULL) 1467 tmp->TM_ZONE = (__aconst char *)__UNCONST(gmt); 1468 else tmp->TM_ZONE = gmtptr->chars; 1469 } 1470#endif /* defined TM_ZONE */ 1471 return result; 1472} 1473 1474struct tm * 1475gmtime(const time_t *const timep) 1476{ 1477 struct tm *tmp = gmtsub(NULL, timep, 0L, &tm); 1478 1479 if (tmp == NULL) 1480 errno = EOVERFLOW; 1481 1482 return tmp; 1483} 1484 1485/* 1486** Re-entrant version of gmtime. 1487*/ 1488 1489struct tm * 1490gmtime_r(const time_t * const timep, struct tm *tmp) 1491{ 1492 tmp = gmtsub(NULL, timep, 0L, tmp); 1493 1494 if (tmp == NULL) 1495 errno = EOVERFLOW; 1496 1497 return tmp; 1498} 1499 1500#ifdef STD_INSPIRED 1501 1502struct tm * 1503offtime(const time_t *const timep, long offset) 1504{ 1505 struct tm *tmp = gmtsub(NULL, timep, offset, &tm); 1506 1507 if (tmp == NULL) 1508 errno = EOVERFLOW; 1509 1510 return tmp; 1511} 1512 1513struct tm * 1514offtime_r(const time_t *timep, long offset, struct tm *tmp) 1515{ 1516 tmp = gmtsub(NULL, timep, offset, tmp); 1517 1518 if (tmp == NULL) 1519 errno = EOVERFLOW; 1520 1521 return tmp; 1522} 1523 1524#endif /* defined STD_INSPIRED */ 1525 1526/* 1527** Return the number of leap years through the end of the given year 1528** where, to make the math easy, the answer for year zero is defined as zero. 1529*/ 1530 1531static int 1532leaps_thru_end_of(const int y) 1533{ 1534 return (y >= 0) ? (y / 4 - y / 100 + y / 400) : 1535 -(leaps_thru_end_of(-(y + 1)) + 1); 1536} 1537 1538static struct tm * 1539timesub(const timezone_t sp, const time_t *const timep, const long offset, 1540 struct tm *const tmp) 1541{ 1542 const struct lsinfo * lp; 1543 time_t tdays; 1544 int idays; /* unsigned would be so 2003 */ 1545 long rem; 1546 int y; 1547 const int * ip; 1548 long corr; 1549 int hit; 1550 int i; 1551 1552 corr = 0; 1553 hit = 0; 1554 i = (sp == NULL) ? 0 : sp->leapcnt; 1555 while (--i >= 0) { 1556 lp = &sp->lsis[i]; 1557 if (*timep >= lp->ls_trans) { 1558 if (*timep == lp->ls_trans) { 1559 hit = ((i == 0 && lp->ls_corr > 0) || 1560 lp->ls_corr > sp->lsis[i - 1].ls_corr); 1561 if (hit) 1562 while (i > 0 && 1563 sp->lsis[i].ls_trans == 1564 sp->lsis[i - 1].ls_trans + 1 && 1565 sp->lsis[i].ls_corr == 1566 sp->lsis[i - 1].ls_corr + 1) { 1567 ++hit; 1568 --i; 1569 } 1570 } 1571 corr = lp->ls_corr; 1572 break; 1573 } 1574 } 1575 y = EPOCH_YEAR; 1576 tdays = *timep / SECSPERDAY; 1577 rem = (long) (*timep - tdays * SECSPERDAY); 1578 while (tdays < 0 || tdays >= year_lengths[isleap(y)]) { 1579 int newy; 1580 time_t tdelta; 1581 int idelta; 1582 int leapdays; 1583 1584 tdelta = tdays / DAYSPERLYEAR; 1585 idelta = (int) tdelta; 1586 if (tdelta - idelta >= 1 || idelta - tdelta >= 1) 1587 return NULL; 1588 if (idelta == 0) 1589 idelta = (tdays < 0) ? -1 : 1; 1590 newy = y; 1591 if (increment_overflow(&newy, idelta)) 1592 return NULL; 1593 leapdays = leaps_thru_end_of(newy - 1) - 1594 leaps_thru_end_of(y - 1); 1595 tdays -= ((time_t) newy - y) * DAYSPERNYEAR; 1596 tdays -= leapdays; 1597 y = newy; 1598 } 1599 { 1600 long seconds; 1601 1602 seconds = tdays * SECSPERDAY + 0.5; 1603 tdays = seconds / SECSPERDAY; 1604 rem += (long) (seconds - tdays * SECSPERDAY); 1605 } 1606 /* 1607 ** Given the range, we can now fearlessly cast... 1608 */ 1609 idays = (int) tdays; 1610 rem += offset - corr; 1611 while (rem < 0) { 1612 rem += SECSPERDAY; 1613 --idays; 1614 } 1615 while (rem >= SECSPERDAY) { 1616 rem -= SECSPERDAY; 1617 ++idays; 1618 } 1619 while (idays < 0) { 1620 if (increment_overflow(&y, -1)) 1621 return NULL; 1622 idays += year_lengths[isleap(y)]; 1623 } 1624 while (idays >= year_lengths[isleap(y)]) { 1625 idays -= year_lengths[isleap(y)]; 1626 if (increment_overflow(&y, 1)) 1627 return NULL; 1628 } 1629 tmp->tm_year = y; 1630 if (increment_overflow(&tmp->tm_year, -TM_YEAR_BASE)) 1631 return NULL; 1632 tmp->tm_yday = idays; 1633 /* 1634 ** The "extra" mods below avoid overflow problems. 1635 */ 1636 tmp->tm_wday = EPOCH_WDAY + 1637 ((y - EPOCH_YEAR) % DAYSPERWEEK) * 1638 (DAYSPERNYEAR % DAYSPERWEEK) + 1639 leaps_thru_end_of(y - 1) - 1640 leaps_thru_end_of(EPOCH_YEAR - 1) + 1641 idays; 1642 tmp->tm_wday %= DAYSPERWEEK; 1643 if (tmp->tm_wday < 0) 1644 tmp->tm_wday += DAYSPERWEEK; 1645 tmp->tm_hour = (int) (rem / SECSPERHOUR); 1646 rem %= SECSPERHOUR; 1647 tmp->tm_min = (int) (rem / SECSPERMIN); 1648 /* 1649 ** A positive leap second requires a special 1650 ** representation. This uses "... ??:59:60" et seq. 1651 */ 1652 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit; 1653 ip = mon_lengths[isleap(y)]; 1654 for (tmp->tm_mon = 0; idays >= ip[tmp->tm_mon]; ++(tmp->tm_mon)) 1655 idays -= ip[tmp->tm_mon]; 1656 tmp->tm_mday = (int) (idays + 1); 1657 tmp->tm_isdst = 0; 1658#ifdef TM_GMTOFF 1659 tmp->TM_GMTOFF = offset; 1660#endif /* defined TM_GMTOFF */ 1661 return tmp; 1662} 1663 1664char * 1665ctime(const time_t *const timep) 1666{ 1667/* 1668** Section 4.12.3.2 of X3.159-1989 requires that 1669** The ctime function converts the calendar time pointed to by timer 1670** to local time in the form of a string. It is equivalent to 1671** asctime(localtime(timer)) 1672*/ 1673 struct tm *rtm = localtime(timep); 1674 if (rtm == NULL) 1675 return NULL; 1676 return asctime(rtm); 1677} 1678 1679char * 1680ctime_r(const time_t *const timep, char *buf) 1681{ 1682 struct tm mytm, *rtm; 1683 1684 rtm = localtime_r(timep, &mytm); 1685 if (rtm == NULL) 1686 return NULL; 1687 return asctime_r(rtm, buf); 1688} 1689 1690char * 1691ctime_rz(const timezone_t sp, const time_t * timep, char *buf) 1692{ 1693 struct tm mytm, *rtm; 1694 1695 rtm = localtime_rz(sp, timep, &mytm); 1696 if (rtm == NULL) 1697 return NULL; 1698 return asctime_r(rtm, buf); 1699} 1700 1701/* 1702** Adapted from code provided by Robert Elz, who writes: 1703** The "best" way to do mktime I think is based on an idea of Bob 1704** Kridle's (so its said...) from a long time ago. 1705** It does a binary search of the time_t space. Since time_t's are 1706** just 32 bits, its a max of 32 iterations (even at 64 bits it 1707** would still be very reasonable). 1708*/ 1709 1710#ifndef WRONG 1711#define WRONG ((time_t)-1) 1712#endif /* !defined WRONG */ 1713 1714/* 1715** Simplified normalize logic courtesy Paul Eggert. 1716*/ 1717 1718static int 1719increment_overflow(int *ip, int j) 1720{ 1721 int i = *ip; 1722 1723 /* 1724 ** If i >= 0 there can only be overflow if i + j > INT_MAX 1725 ** or if j > INT_MAX - i; given i >= 0, INT_MAX - i cannot overflow. 1726 ** If i < 0 there can only be overflow if i + j < INT_MIN 1727 ** or if j < INT_MIN - i; given i < 0, INT_MIN - i cannot overflow. 1728 */ 1729 if ((i >= 0) ? (j > INT_MAX - i) : (j < INT_MIN - i)) 1730 return TRUE; 1731 *ip += j; 1732 return FALSE; 1733} 1734 1735static int 1736long_increment_overflow(long *lp, int m) 1737{ 1738 long l = *lp; 1739 1740 if ((l >= 0) ? (m > LONG_MAX - l) : (m < LONG_MIN - l)) 1741 return TRUE; 1742 *lp += m; 1743 return FALSE; 1744} 1745 1746static int 1747normalize_overflow(int *const tensptr, int *const unitsptr, const int base) 1748{ 1749 int tensdelta; 1750 1751 tensdelta = (*unitsptr >= 0) ? 1752 (*unitsptr / base) : 1753 (-1 - (-1 - *unitsptr) / base); 1754 *unitsptr -= tensdelta * base; 1755 return increment_overflow(tensptr, tensdelta); 1756} 1757 1758static int 1759long_normalize_overflow(long *const tensptr, int *const unitsptr, 1760 const int base) 1761{ 1762 int tensdelta; 1763 1764 tensdelta = (*unitsptr >= 0) ? 1765 (*unitsptr / base) : 1766 (-1 - (-1 - *unitsptr) / base); 1767 *unitsptr -= tensdelta * base; 1768 return long_increment_overflow(tensptr, tensdelta); 1769} 1770 1771static int 1772tmcomp(const struct tm *const atmp, const struct tm *const btmp) 1773{ 1774 int result; 1775 1776 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 && 1777 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 && 1778 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && 1779 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && 1780 (result = (atmp->tm_min - btmp->tm_min)) == 0) 1781 result = atmp->tm_sec - btmp->tm_sec; 1782 return result; 1783} 1784 1785static time_t 1786time2sub(const timezone_t sp, struct tm *const tmp, subfun_t funcp, 1787 const long offset, int *const okayp, const int do_norm_secs) 1788{ 1789 int dir; 1790 int i, j; 1791 int saved_seconds; 1792 long li; 1793 time_t lo; 1794 time_t hi; 1795#ifdef NO_ERROR_IN_DST_GAP 1796 time_t ilo; 1797#endif 1798 long y; 1799 time_t newt; 1800 time_t t; 1801 struct tm yourtm, mytm; 1802 1803 *okayp = FALSE; 1804 yourtm = *tmp; 1805 if (do_norm_secs) { 1806 if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec, 1807 SECSPERMIN)) 1808 goto overflow; 1809 } 1810 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) 1811 goto overflow; 1812 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) 1813 goto overflow; 1814 y = yourtm.tm_year; 1815 if (long_normalize_overflow(&y, &yourtm.tm_mon, MONSPERYEAR)) 1816 goto overflow; 1817 /* 1818 ** Turn y into an actual year number for now. 1819 ** It is converted back to an offset from TM_YEAR_BASE later. 1820 */ 1821 if (long_increment_overflow(&y, TM_YEAR_BASE)) 1822 goto overflow; 1823 while (yourtm.tm_mday <= 0) { 1824 if (long_increment_overflow(&y, -1)) 1825 goto overflow; 1826 li = y + (1 < yourtm.tm_mon); 1827 yourtm.tm_mday += year_lengths[isleap(li)]; 1828 } 1829 while (yourtm.tm_mday > DAYSPERLYEAR) { 1830 li = y + (1 < yourtm.tm_mon); 1831 yourtm.tm_mday -= year_lengths[isleap(li)]; 1832 if (long_increment_overflow(&y, 1)) 1833 goto overflow; 1834 } 1835 for ( ; ; ) { 1836 i = mon_lengths[isleap(y)][yourtm.tm_mon]; 1837 if (yourtm.tm_mday <= i) 1838 break; 1839 yourtm.tm_mday -= i; 1840 if (++yourtm.tm_mon >= MONSPERYEAR) { 1841 yourtm.tm_mon = 0; 1842 if (long_increment_overflow(&y, 1)) 1843 goto overflow; 1844 } 1845 } 1846 if (long_increment_overflow(&y, -TM_YEAR_BASE)) 1847 goto overflow; 1848 yourtm.tm_year = y; 1849 if (yourtm.tm_year != y) 1850 goto overflow; 1851 if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN) 1852 saved_seconds = 0; 1853 else if (y + TM_YEAR_BASE < EPOCH_YEAR) { 1854 /* 1855 ** We can't set tm_sec to 0, because that might push the 1856 ** time below the minimum representable time. 1857 ** Set tm_sec to 59 instead. 1858 ** This assumes that the minimum representable time is 1859 ** not in the same minute that a leap second was deleted from, 1860 ** which is a safer assumption than using 58 would be. 1861 */ 1862 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) 1863 goto overflow; 1864 saved_seconds = yourtm.tm_sec; 1865 yourtm.tm_sec = SECSPERMIN - 1; 1866 } else { 1867 saved_seconds = yourtm.tm_sec; 1868 yourtm.tm_sec = 0; 1869 } 1870 /* 1871 ** Do a binary search (this works whatever time_t's type is). 1872 */ 1873/* LINTED constant */ 1874 if (!TYPE_SIGNED(time_t)) { 1875 lo = 0; 1876 hi = lo - 1; 1877/* LINTED constant */ 1878 } else if (!TYPE_INTEGRAL(time_t)) { 1879/* CONSTCOND */ 1880 if (sizeof(time_t) > sizeof(float)) 1881/* LINTED assumed double */ 1882 hi = (time_t) DBL_MAX; 1883/* LINTED assumed float */ 1884 else hi = (time_t) FLT_MAX; 1885 lo = -hi; 1886 } else { 1887 lo = 1; 1888 for (i = 0; i < (int) TYPE_BIT(time_t) - 1; ++i) 1889 lo *= 2; 1890 hi = -(lo + 1); 1891 } 1892#ifdef NO_ERROR_IN_DST_GAP 1893 ilo = lo; 1894#endif 1895 for ( ; ; ) { 1896 t = lo / 2 + hi / 2; 1897 if (t < lo) 1898 t = lo; 1899 else if (t > hi) 1900 t = hi; 1901 if ((*funcp)(sp, &t, offset, &mytm) == NULL) { 1902 /* 1903 ** Assume that t is too extreme to be represented in 1904 ** a struct tm; arrange things so that it is less 1905 ** extreme on the next pass. 1906 */ 1907 dir = (t > 0) ? 1 : -1; 1908 } else dir = tmcomp(&mytm, &yourtm); 1909 if (dir != 0) { 1910 if (t == lo) { 1911 ++t; 1912 if (t <= lo) 1913 goto overflow; 1914 ++lo; 1915 } else if (t == hi) { 1916 --t; 1917 if (t >= hi) 1918 goto overflow; 1919 --hi; 1920 } 1921#ifdef NO_ERROR_IN_DST_GAP 1922 if (ilo != lo && lo - 1 == hi && yourtm.tm_isdst < 0) { 1923 time_t off = 0; 1924 for (i = sp->typecnt - 1; i >= 0; --i) { 1925 for (j = sp->typecnt - 1; j >= 0; --j) { 1926 if (sp->ttis[j].tt_isdst == 1927 sp->ttis[i].tt_isdst) 1928 continue; 1929 off = sp->ttis[j].tt_gmtoff - 1930 sp->ttis[i].tt_gmtoff; 1931 break; 1932 } 1933 if (j >= 0) 1934 break; 1935 } 1936 if (off) { 1937 t = hi; 1938 break; 1939 } 1940 } 1941#endif 1942 if (lo > hi) 1943 goto invalid; 1944 if (dir > 0) 1945 hi = t; 1946 else lo = t; 1947 continue; 1948 } 1949 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) 1950 break; 1951 /* 1952 ** Right time, wrong type. 1953 ** Hunt for right time, right type. 1954 ** It's okay to guess wrong since the guess 1955 ** gets checked. 1956 */ 1957 if (sp == NULL) 1958 goto invalid; 1959 for (i = sp->typecnt - 1; i >= 0; --i) { 1960 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) 1961 continue; 1962 for (j = sp->typecnt - 1; j >= 0; --j) { 1963 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) 1964 continue; 1965 newt = t + sp->ttis[j].tt_gmtoff - 1966 sp->ttis[i].tt_gmtoff; 1967 if ((*funcp)(sp, &newt, offset, &mytm) == NULL) 1968 continue; 1969 if (tmcomp(&mytm, &yourtm) != 0) 1970 continue; 1971 if (mytm.tm_isdst != yourtm.tm_isdst) 1972 continue; 1973 /* 1974 ** We have a match. 1975 */ 1976 t = newt; 1977 goto label; 1978 } 1979 } 1980 goto invalid; 1981 } 1982label: 1983 newt = t + saved_seconds; 1984 if ((newt < t) != (saved_seconds < 0)) 1985 goto overflow; 1986 t = newt; 1987 if ((*funcp)(sp, &t, offset, tmp)) { 1988 *okayp = TRUE; 1989 return t; 1990 } 1991overflow: 1992 errno = EOVERFLOW; 1993 return WRONG; 1994invalid: 1995 errno = EINVAL; 1996 return WRONG; 1997} 1998 1999static time_t 2000time2(const timezone_t sp, struct tm *const tmp, subfun_t funcp, 2001 const long offset, int *const okayp) 2002{ 2003 time_t t; 2004 2005 /* 2006 ** First try without normalization of seconds 2007 ** (in case tm_sec contains a value associated with a leap second). 2008 ** If that fails, try with normalization of seconds. 2009 */ 2010 t = time2sub(sp, tmp, funcp, offset, okayp, FALSE); 2011 return *okayp ? t : time2sub(sp, tmp, funcp, offset, okayp, TRUE); 2012} 2013 2014static time_t 2015time1(const timezone_t sp, struct tm *const tmp, subfun_t funcp, 2016 long offset) 2017{ 2018 time_t t; 2019 int samei, otheri; 2020 int sameind, otherind; 2021 int i; 2022 int nseen; 2023 int seen[TZ_MAX_TYPES]; 2024 int types[TZ_MAX_TYPES]; 2025 int okay; 2026 2027 if (tmp == NULL) { 2028 errno = EINVAL; 2029 return WRONG; 2030 } 2031 if (tmp->tm_isdst > 1) 2032 tmp->tm_isdst = 1; 2033 t = time2(sp, tmp, funcp, offset, &okay); 2034#ifdef PCTS 2035 /* 2036 ** PCTS code courtesy Grant Sullivan. 2037 */ 2038 if (okay) 2039 return t; 2040 if (tmp->tm_isdst < 0) 2041 tmp->tm_isdst = 0; /* reset to std and try again */ 2042#endif /* defined PCTS */ 2043#ifndef PCTS 2044 if (okay || tmp->tm_isdst < 0) 2045 return t; 2046#endif /* !defined PCTS */ 2047 /* 2048 ** We're supposed to assume that somebody took a time of one type 2049 ** and did some math on it that yielded a "struct tm" that's bad. 2050 ** We try to divine the type they started from and adjust to the 2051 ** type they need. 2052 */ 2053 if (sp == NULL) { 2054 errno = EINVAL; 2055 return WRONG; 2056 } 2057 for (i = 0; i < sp->typecnt; ++i) 2058 seen[i] = FALSE; 2059 nseen = 0; 2060 for (i = sp->timecnt - 1; i >= 0; --i) 2061 if (!seen[sp->types[i]]) { 2062 seen[sp->types[i]] = TRUE; 2063 types[nseen++] = sp->types[i]; 2064 } 2065 for (sameind = 0; sameind < nseen; ++sameind) { 2066 samei = types[sameind]; 2067 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) 2068 continue; 2069 for (otherind = 0; otherind < nseen; ++otherind) { 2070 otheri = types[otherind]; 2071 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) 2072 continue; 2073 tmp->tm_sec += (int)(sp->ttis[otheri].tt_gmtoff - 2074 sp->ttis[samei].tt_gmtoff); 2075 tmp->tm_isdst = !tmp->tm_isdst; 2076 t = time2(sp, tmp, funcp, offset, &okay); 2077 if (okay) 2078 return t; 2079 tmp->tm_sec -= (int)(sp->ttis[otheri].tt_gmtoff - 2080 sp->ttis[samei].tt_gmtoff); 2081 tmp->tm_isdst = !tmp->tm_isdst; 2082 } 2083 } 2084 errno = EOVERFLOW; 2085 return WRONG; 2086} 2087 2088time_t 2089mktime_z(const timezone_t sp, struct tm *tmp) 2090{ 2091 time_t t; 2092 if (sp == NULL) 2093 t = time1(NULL, tmp, gmtsub, 0L); 2094 else 2095 t = time1(sp, tmp, localsub, 0L); 2096 return t; 2097} 2098 2099time_t 2100mktime(struct tm * const tmp) 2101{ 2102 time_t result; 2103 2104 rwlock_wrlock(&lcl_lock); 2105 tzset_unlocked(); 2106 result = mktime_z(lclptr, tmp); 2107 rwlock_unlock(&lcl_lock); 2108 return result; 2109} 2110 2111#ifdef STD_INSPIRED 2112 2113time_t 2114timelocal_z(const timezone_t sp, struct tm *tmp) 2115{ 2116 if (tmp != NULL) 2117 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 2118 return mktime_z(sp, tmp); 2119} 2120 2121time_t 2122timelocal(struct tm *const tmp) 2123{ 2124 if (tmp != NULL) 2125 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 2126 return mktime(tmp); 2127} 2128 2129time_t 2130timegm(struct tm *const tmp) 2131{ 2132 time_t t; 2133 2134 if (tmp != NULL) 2135 tmp->tm_isdst = 0; 2136 t = time1(gmtptr, tmp, gmtsub, 0L); 2137 if (t == WRONG) 2138 errno = EOVERFLOW; 2139 return t; 2140} 2141 2142time_t 2143timeoff(struct tm *const tmp, const long offset) 2144{ 2145 time_t t; 2146 2147 if (tmp != NULL) 2148 tmp->tm_isdst = 0; 2149 t = time1(gmtptr, tmp, gmtsub, offset); 2150 if (t == WRONG) 2151 errno = EOVERFLOW; 2152 return t; 2153} 2154 2155#endif /* defined STD_INSPIRED */ 2156 2157#ifdef CMUCS 2158 2159/* 2160** The following is supplied for compatibility with 2161** previous versions of the CMUCS runtime library. 2162*/ 2163 2164long 2165gtime(struct tm *const tmp) 2166{ 2167 const time_t t = mktime(tmp); 2168 2169 if (t == WRONG) 2170 return -1; 2171 return t; 2172} 2173 2174#endif /* defined CMUCS */ 2175 2176/* 2177** XXX--is the below the right way to conditionalize?? 2178*/ 2179 2180#ifdef STD_INSPIRED 2181 2182/* 2183** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 2184** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which 2185** is not the case if we are accounting for leap seconds. 2186** So, we provide the following conversion routines for use 2187** when exchanging timestamps with POSIX conforming systems. 2188*/ 2189 2190static long 2191leapcorr(const timezone_t sp, time_t *timep) 2192{ 2193 struct lsinfo * lp; 2194 int i; 2195 2196 i = sp->leapcnt; 2197 while (--i >= 0) { 2198 lp = &sp->lsis[i]; 2199 if (*timep >= lp->ls_trans) 2200 return lp->ls_corr; 2201 } 2202 return 0; 2203} 2204 2205time_t 2206time2posix_z(const timezone_t sp, time_t t) 2207{ 2208 return t - leapcorr(sp, &t); 2209} 2210 2211time_t 2212time2posix(time_t t) 2213{ 2214 time_t result; 2215 rwlock_wrlock(&lcl_lock); 2216 tzset_unlocked(); 2217 result = t - leapcorr(lclptr, &t); 2218 rwlock_unlock(&lcl_lock); 2219 return (result); 2220} 2221 2222time_t 2223posix2time_z(const timezone_t sp, time_t t) 2224{ 2225 time_t x; 2226 time_t y; 2227 2228 /* 2229 ** For a positive leap second hit, the result 2230 ** is not unique. For a negative leap second 2231 ** hit, the corresponding time doesn't exist, 2232 ** so we return an adjacent second. 2233 */ 2234 x = t + leapcorr(sp, &t); 2235 y = x - leapcorr(sp, &x); 2236 if (y < t) { 2237 do { 2238 x++; 2239 y = x - leapcorr(sp, &x); 2240 } while (y < t); 2241 if (t != y) { 2242 return x - 1; 2243 } 2244 } else if (y > t) { 2245 do { 2246 --x; 2247 y = x - leapcorr(sp, &x); 2248 } while (y > t); 2249 if (t != y) { 2250 return x + 1; 2251 } 2252 } 2253 return x; 2254} 2255 2256 2257 2258time_t 2259posix2time(time_t t) 2260{ 2261 time_t result; 2262 2263 rwlock_wrlock(&lcl_lock); 2264 tzset_unlocked(); 2265 result = posix2time_z(lclptr, t); 2266 rwlock_unlock(&lcl_lock); 2267 return result; 2268} 2269 2270#endif /* defined STD_INSPIRED */ 2271