1 /* 2 ** This file is in the public domain, so clarified as of 3 ** 1996-06-05 by Arthur David Olson. 4 ** 5 ** @(#)localtime.c 8.9 6 ** $FreeBSD: src/lib/libc/stdtime/localtime.c,v 1.25.2.2 2002/08/13 16:08:07 bmilekic Exp $ 7 ** $DragonFly: src/lib/libc/stdtime/localtime.c,v 1.7 2008/10/19 20:15:58 swildner Exp $ 8 */ 9 10 /* 11 ** Leap second handling from Bradley White. 12 ** POSIX-style TZ environment variable handling from Guy Harris. 13 */ 14 15 /*LINTLIBRARY*/ 16 17 #include "namespace.h" 18 #include <sys/types.h> 19 #include <sys/stat.h> 20 21 #include <fcntl.h> 22 #include <float.h> /* for FLT_MAX and DBL_MAX */ 23 #include <time.h> 24 #include <pthread.h> 25 #include "private.h" 26 #include <un-namespace.h> 27 28 #include "tzfile.h" 29 30 #include "libc_private.h" 31 32 #define _MUTEX_LOCK(x) if (__isthreaded) _pthread_mutex_lock(x) 33 #define _MUTEX_UNLOCK(x) if (__isthreaded) _pthread_mutex_unlock(x) 34 35 #ifndef TZ_ABBR_MAX_LEN 36 #define TZ_ABBR_MAX_LEN 16 37 #endif /* !defined TZ_ABBR_MAX_LEN */ 38 39 #ifndef TZ_ABBR_CHAR_SET 40 #define TZ_ABBR_CHAR_SET \ 41 "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 :+-._" 42 #endif /* !defined TZ_ABBR_CHAR_SET */ 43 44 #ifndef TZ_ABBR_ERR_CHAR 45 #define TZ_ABBR_ERR_CHAR '_' 46 #endif /* !defined TZ_ABBR_ERR_CHAR */ 47 48 /* 49 ** SunOS 4.1.1 headers lack O_BINARY. 50 */ 51 52 #ifdef O_BINARY 53 #define OPEN_MODE (O_RDONLY | O_BINARY) 54 #endif /* defined O_BINARY */ 55 #ifndef O_BINARY 56 #define OPEN_MODE O_RDONLY 57 #endif /* !defined O_BINARY */ 58 59 #ifndef WILDABBR 60 /* 61 ** Someone might make incorrect use of a time zone abbreviation: 62 ** 1. They might reference tzname[0] before calling tzset (explicitly 63 ** or implicitly). 64 ** 2. They might reference tzname[1] before calling tzset (explicitly 65 ** or implicitly). 66 ** 3. They might reference tzname[1] after setting to a time zone 67 ** in which Daylight Saving Time is never observed. 68 ** 4. They might reference tzname[0] after setting to a time zone 69 ** in which Standard Time is never observed. 70 ** 5. They might reference tm.TM_ZONE after calling offtime. 71 ** What's best to do in the above cases is open to debate; 72 ** for now, we just set things up so that in any of the five cases 73 ** WILDABBR is used. Another possibility: initialize tzname[0] to the 74 ** string "tzname[0] used before set", and similarly for the other cases. 75 ** And another: initialize tzname[0] to "ERA", with an explanation in the 76 ** manual page of what this "time zone abbreviation" means (doing this so 77 ** that tzname[0] has the "normal" length of three characters). 78 */ 79 #define WILDABBR " " 80 #endif /* !defined WILDABBR */ 81 82 static char wildabbr[] = WILDABBR; 83 84 static const char gmt[] = "GMT"; 85 86 /* 87 ** The DST rules to use if TZ has no rules and we can't load TZDEFRULES. 88 ** We default to US rules as of 1999-08-17. 89 ** POSIX 1003.1 section 8.1.1 says that the default DST rules are 90 ** implementation dependent; for historical reasons, US rules are a 91 ** common default. 92 */ 93 #ifndef TZDEFRULESTRING 94 #define TZDEFRULESTRING ",M4.1.0,M10.5.0" 95 #endif /* !defined TZDEFDST */ 96 97 struct ttinfo { /* time type information */ 98 long tt_gmtoff; /* UTC offset in seconds */ 99 int tt_isdst; /* used to set tm_isdst */ 100 int tt_abbrind; /* abbreviation list index */ 101 int tt_ttisstd; /* TRUE if transition is std time */ 102 int tt_ttisgmt; /* TRUE if transition is UTC */ 103 }; 104 105 struct lsinfo { /* leap second information */ 106 time_t ls_trans; /* transition time */ 107 long ls_corr; /* correction to apply */ 108 }; 109 110 #define BIGGEST(a, b) (((a) > (b)) ? (a) : (b)) 111 112 #ifdef TZNAME_MAX 113 #define MY_TZNAME_MAX TZNAME_MAX 114 #endif /* defined TZNAME_MAX */ 115 #ifndef TZNAME_MAX 116 #define MY_TZNAME_MAX 255 117 #endif /* !defined TZNAME_MAX */ 118 119 struct state { 120 int leapcnt; 121 int timecnt; 122 int typecnt; 123 int charcnt; 124 int goback; 125 int goahead; 126 time_t ats[TZ_MAX_TIMES]; 127 unsigned char types[TZ_MAX_TIMES]; 128 struct ttinfo ttis[TZ_MAX_TYPES]; 129 char chars[BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt), 130 (2 * (MY_TZNAME_MAX + 1)))]; 131 struct lsinfo lsis[TZ_MAX_LEAPS]; 132 }; 133 134 struct rule { 135 int r_type; /* type of rule--see below */ 136 int r_day; /* day number of rule */ 137 int r_week; /* week number of rule */ 138 int r_mon; /* month number of rule */ 139 long r_time; /* transition time of rule */ 140 }; 141 142 #define JULIAN_DAY 0 /* Jn - Julian day */ 143 #define DAY_OF_YEAR 1 /* n - day of year */ 144 #define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */ 145 146 /* 147 ** Prototypes for static functions. 148 */ 149 150 static long detzcode(const char * codep); 151 static time_t detzcode64(const char * codep); 152 static int differ_by_repeat(time_t t1, time_t t0); 153 static const char * getzname(const char * strp); 154 static const char * getqzname(const char * strp, const int delim); 155 static const char * getnum(const char * strp, int * nump, int min, 156 int max); 157 static const char * getsecs(const char * strp, long * secsp); 158 static const char * getoffset(const char * strp, long * offsetp); 159 static const char * getrule(const char * strp, struct rule * rulep); 160 static void gmtload(struct state * sp); 161 static struct tm * gmtsub(const time_t * timep, long offset, 162 struct tm * tmp); 163 static struct tm * localsub(const time_t * timep, long offset, 164 struct tm * tmp); 165 static int increment_overflow(int * number, int delta); 166 static int leaps_thru_end_of(int y); 167 static int long_increment_overflow(long * number, int delta); 168 static int long_normalize_overflow(long * tensptr, 169 int * unitsptr, int base); 170 static int normalize_overflow(int * tensptr, int * unitsptr, 171 int base); 172 static void settzname(void); 173 static time_t time1(struct tm * tmp, 174 struct tm * (*funcp)(const time_t *, 175 long, struct tm *), 176 long offset); 177 static time_t time2(struct tm *tmp, 178 struct tm * (*funcp)(const time_t *, 179 long, struct tm*), 180 long offset, int * okayp); 181 static time_t time2sub(struct tm *tmp, 182 struct tm * (*funcp)(const time_t *, 183 long, struct tm*), 184 long offset, int * okayp, int do_norm_secs); 185 static struct tm * timesub(const time_t * timep, long offset, 186 const struct state * sp, struct tm * tmp); 187 static int tmcomp(const struct tm * atmp, 188 const struct tm * btmp); 189 static time_t transtime(time_t janfirst, int year, 190 const struct rule * rulep, long offset); 191 static int typesequiv(const struct state * sp, int a, int b); 192 static int tzload(const char * name, struct state * sp, 193 int doextend); 194 static int tzparse(const char * name, struct state * sp, 195 int lastditch); 196 197 #ifdef ALL_STATE 198 static struct state * lclptr; 199 static struct state * gmtptr; 200 #endif /* defined ALL_STATE */ 201 202 #ifndef ALL_STATE 203 static struct state lclmem; 204 static struct state gmtmem; 205 #define lclptr (&lclmem) 206 #define gmtptr (&gmtmem) 207 #endif /* State Farm */ 208 209 #ifndef TZ_STRLEN_MAX 210 #define TZ_STRLEN_MAX 255 211 #endif /* !defined TZ_STRLEN_MAX */ 212 213 static char lcl_TZname[TZ_STRLEN_MAX + 1]; 214 static int lcl_is_set; 215 static int gmt_is_set; 216 static pthread_mutex_t lcl_mutex = PTHREAD_MUTEX_INITIALIZER; 217 static pthread_mutex_t gmt_mutex = PTHREAD_MUTEX_INITIALIZER; 218 219 char * tzname[2] = { 220 wildabbr, 221 wildabbr 222 }; 223 224 /* 225 ** Section 4.12.3 of X3.159-1989 requires that 226 ** Except for the strftime function, these functions [asctime, 227 ** ctime, gmtime, localtime] return values in one of two static 228 ** objects: a broken-down time structure and an array of char. 229 ** Thanks to Paul Eggert for noting this. 230 */ 231 232 static struct tm tm; 233 234 #ifdef USG_COMPAT 235 time_t timezone = 0; 236 int daylight = 0; 237 #endif /* defined USG_COMPAT */ 238 239 #ifdef ALTZONE 240 time_t altzone = 0; 241 #endif /* defined ALTZONE */ 242 243 static long 244 detzcode(const char * const codep) 245 { 246 long result; 247 int i; 248 249 result = (codep[0] & 0x80) ? ~0L : 0; 250 for (i = 0; i < 4; ++i) 251 result = (result << 8) | (codep[i] & 0xff); 252 return result; 253 } 254 255 static time_t 256 detzcode64(const char * const codep) 257 { 258 time_t result; 259 int i; 260 261 result = (codep[0] & 0x80) ? (~(int_fast64_t) 0) : 0; 262 for (i = 0; i < 8; ++i) 263 result = result * 256 + (codep[i] & 0xff); 264 return result; 265 } 266 267 static void 268 settzname(void) 269 { 270 struct state * const sp = lclptr; 271 int i; 272 273 tzname[0] = wildabbr; 274 tzname[1] = wildabbr; 275 #ifdef USG_COMPAT 276 daylight = 0; 277 timezone = 0; 278 #endif /* defined USG_COMPAT */ 279 #ifdef ALTZONE 280 altzone = 0; 281 #endif /* defined ALTZONE */ 282 #ifdef ALL_STATE 283 if (sp == NULL) { 284 tzname[0] = tzname[1] = gmt; 285 return; 286 } 287 #endif /* defined ALL_STATE */ 288 for (i = 0; i < sp->typecnt; ++i) { 289 const struct ttinfo * const ttisp = &sp->ttis[i]; 290 291 tzname[ttisp->tt_isdst] = 292 &sp->chars[ttisp->tt_abbrind]; 293 #ifdef USG_COMPAT 294 if (ttisp->tt_isdst) 295 daylight = 1; 296 if (i == 0 || !ttisp->tt_isdst) 297 timezone = -(ttisp->tt_gmtoff); 298 #endif /* defined USG_COMPAT */ 299 #ifdef ALTZONE 300 if (i == 0 || ttisp->tt_isdst) 301 altzone = -(ttisp->tt_gmtoff); 302 #endif /* defined ALTZONE */ 303 } 304 /* 305 ** And to get the latest zone names into tzname. . . 306 */ 307 for (i = 0; i < sp->timecnt; ++i) { 308 const struct ttinfo * const ttisp = 309 &sp->ttis[ 310 sp->types[i]]; 311 312 tzname[ttisp->tt_isdst] = 313 &sp->chars[ttisp->tt_abbrind]; 314 } 315 /* 316 ** Finally, scrub the abbreviations. 317 ** First, replace bogus characters. 318 */ 319 for (i = 0; i < sp->charcnt; ++i) 320 if (strchr(TZ_ABBR_CHAR_SET, sp->chars[i]) == NULL) 321 sp->chars[i] = TZ_ABBR_ERR_CHAR; 322 /* 323 ** Second, truncate long abbreviations. 324 */ 325 for (i = 0; i < sp->typecnt; ++i) { 326 const struct ttinfo * const ttisp = &sp->ttis[i]; 327 char * cp = &sp->chars[ttisp->tt_abbrind]; 328 329 if (strlen(cp) > TZ_ABBR_MAX_LEN && 330 strcmp(cp, GRANDPARENTED) != 0) 331 *(cp + TZ_ABBR_MAX_LEN) = '\0'; 332 } 333 } 334 335 static int 336 differ_by_repeat(const time_t t1, const time_t t0) 337 { 338 if (TYPE_INTEGRAL(time_t) && 339 TYPE_BIT(time_t) - TYPE_SIGNED(time_t) < SECSPERREPEAT_BITS) 340 return 0; 341 return t1 - t0 == SECSPERREPEAT; 342 } 343 344 static int 345 tzload(const char *name, struct state * const sp, const int doextend) 346 { 347 const char * p; 348 int i; 349 int fid; 350 int stored; 351 int nread; 352 union { 353 struct tzhead tzhead; 354 char buf[2 * sizeof(struct tzhead) + 355 2 * sizeof *sp + 356 4 * TZ_MAX_TIMES]; 357 } u; 358 359 /* XXX The following is from OpenBSD, and I'm not sure it is correct */ 360 if (name != NULL && issetugid() != 0) 361 if ((name[0] == ':' && name[1] == '/') || 362 name[0] == '/' || strchr(name, '.')) 363 name = NULL; 364 if (name == NULL && (name = TZDEFAULT) == NULL) 365 return -1; 366 { 367 int doaccess; 368 struct stat stab; 369 /* 370 ** Section 4.9.1 of the C standard says that 371 ** "FILENAME_MAX expands to an integral constant expression 372 ** that is the size needed for an array of char large enough 373 ** to hold the longest file name string that the implementation 374 ** guarantees can be opened." 375 */ 376 char fullname[FILENAME_MAX + 1]; 377 378 if (name[0] == ':') 379 ++name; 380 doaccess = name[0] == '/'; 381 if (!doaccess) { 382 if ((p = TZDIR) == NULL) 383 return -1; 384 if ((strlen(p) + 1 + strlen(name) + 1) >= sizeof fullname) 385 return -1; 386 strcpy(fullname, p); 387 strcat(fullname, "/"); 388 strcat(fullname, name); 389 /* 390 ** Set doaccess if '.' (as in "../") shows up in name. 391 */ 392 if (strchr(name, '.') != NULL) 393 doaccess = TRUE; 394 name = fullname; 395 } 396 if (doaccess && access(name, R_OK) != 0) 397 return -1; 398 if ((fid = _open(name, OPEN_MODE)) == -1) 399 return -1; 400 if ((_fstat(fid, &stab) < 0) || !S_ISREG(stab.st_mode)) { 401 _close(fid); 402 return -1; 403 } 404 } 405 nread = read(fid, u.buf, sizeof u.buf); 406 if (close(fid) < 0 || nread <= 0) 407 return -1; 408 for (stored = 4; stored <= 8; stored *= 2) { 409 int ttisstdcnt; 410 int ttisgmtcnt; 411 412 ttisstdcnt = (int) detzcode(u.tzhead.tzh_ttisstdcnt); 413 ttisgmtcnt = (int) detzcode(u.tzhead.tzh_ttisgmtcnt); 414 sp->leapcnt = (int) detzcode(u.tzhead.tzh_leapcnt); 415 sp->timecnt = (int) detzcode(u.tzhead.tzh_timecnt); 416 sp->typecnt = (int) detzcode(u.tzhead.tzh_typecnt); 417 sp->charcnt = (int) detzcode(u.tzhead.tzh_charcnt); 418 p = u.tzhead.tzh_charcnt + sizeof u.tzhead.tzh_charcnt; 419 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS || 420 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES || 421 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES || 422 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS || 423 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) || 424 (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0)) 425 return -1; 426 if (nread - (p - u.buf) < 427 sp->timecnt * stored + /* ats */ 428 sp->timecnt + /* types */ 429 sp->typecnt * 6 + /* ttinfos */ 430 sp->charcnt + /* chars */ 431 sp->leapcnt * (stored + 4) + /* lsinfos */ 432 ttisstdcnt + /* ttisstds */ 433 ttisgmtcnt) /* ttisgmts */ 434 return -1; 435 for (i = 0; i < sp->timecnt; ++i) { 436 sp->ats[i] = (stored == 4) ? 437 detzcode(p) : detzcode64(p); 438 p += stored; 439 } 440 for (i = 0; i < sp->timecnt; ++i) { 441 sp->types[i] = (unsigned char) *p++; 442 if (sp->types[i] >= sp->typecnt) 443 return -1; 444 } 445 for (i = 0; i < sp->typecnt; ++i) { 446 struct ttinfo * ttisp; 447 448 ttisp = &sp->ttis[i]; 449 ttisp->tt_gmtoff = detzcode(p); 450 p += 4; 451 ttisp->tt_isdst = (unsigned char) *p++; 452 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1) 453 return -1; 454 ttisp->tt_abbrind = (unsigned char) *p++; 455 if (ttisp->tt_abbrind < 0 || 456 ttisp->tt_abbrind > sp->charcnt) 457 return -1; 458 } 459 for (i = 0; i < sp->charcnt; ++i) 460 sp->chars[i] = *p++; 461 sp->chars[i] = '\0'; /* ensure '\0' at end */ 462 for (i = 0; i < sp->leapcnt; ++i) { 463 struct lsinfo * lsisp; 464 465 lsisp = &sp->lsis[i]; 466 lsisp->ls_trans = (stored == 4) ? 467 detzcode(p) : detzcode64(p); 468 p += stored; 469 lsisp->ls_corr = detzcode(p); 470 p += 4; 471 } 472 for (i = 0; i < sp->typecnt; ++i) { 473 struct ttinfo * ttisp; 474 475 ttisp = &sp->ttis[i]; 476 if (ttisstdcnt == 0) 477 ttisp->tt_ttisstd = FALSE; 478 else { 479 ttisp->tt_ttisstd = *p++; 480 if (ttisp->tt_ttisstd != TRUE && 481 ttisp->tt_ttisstd != FALSE) 482 return -1; 483 } 484 } 485 for (i = 0; i < sp->typecnt; ++i) { 486 struct ttinfo * ttisp; 487 488 ttisp = &sp->ttis[i]; 489 if (ttisgmtcnt == 0) 490 ttisp->tt_ttisgmt = FALSE; 491 else { 492 ttisp->tt_ttisgmt = *p++; 493 if (ttisp->tt_ttisgmt != TRUE && 494 ttisp->tt_ttisgmt != FALSE) 495 return -1; 496 } 497 } 498 /* 499 ** Out-of-sort ats should mean we're running on a 500 ** signed time_t system but using a data file with 501 ** unsigned values (or vice versa). 502 */ 503 for (i = 0; i < sp->timecnt - 2; ++i) 504 if (sp->ats[i] > sp->ats[i + 1]) { 505 ++i; 506 if (TYPE_SIGNED(time_t)) { 507 /* 508 ** Ignore the end (easy). 509 */ 510 sp->timecnt = i; 511 } else { 512 /* 513 ** Ignore the beginning (harder). 514 */ 515 int j; 516 517 for (j = 0; j + i < sp->timecnt; ++j) { 518 sp->ats[j] = sp->ats[j + i]; 519 sp->types[j] = sp->types[j + i]; 520 } 521 sp->timecnt = j; 522 } 523 break; 524 } 525 /* 526 ** If this is an old file, we're done. 527 */ 528 if (u.tzhead.tzh_version[0] == '\0') 529 break; 530 nread -= p - u.buf; 531 for (i = 0; i < nread; ++i) 532 u.buf[i] = p[i]; 533 /* 534 ** If this is a narrow integer time_t system, we're done. 535 */ 536 if (stored >= (int) sizeof(time_t) && TYPE_INTEGRAL(time_t)) 537 break; 538 } 539 if (doextend && nread > 2 && 540 u.buf[0] == '\n' && u.buf[nread - 1] == '\n' && 541 sp->typecnt + 2 <= TZ_MAX_TYPES) { 542 struct state ts; 543 int result; 544 545 u.buf[nread - 1] = '\0'; 546 result = tzparse(&u.buf[1], &ts, FALSE); 547 if (result == 0 && ts.typecnt == 2 && 548 sp->charcnt + ts.charcnt <= TZ_MAX_CHARS) { 549 for (i = 0; i < 2; ++i) 550 ts.ttis[i].tt_abbrind += 551 sp->charcnt; 552 for (i = 0; i < ts.charcnt; ++i) 553 sp->chars[sp->charcnt++] = 554 ts.chars[i]; 555 i = 0; 556 while (i < ts.timecnt && 557 ts.ats[i] <= 558 sp->ats[sp->timecnt - 1]) 559 ++i; 560 while (i < ts.timecnt && 561 sp->timecnt < TZ_MAX_TIMES) { 562 sp->ats[sp->timecnt] = 563 ts.ats[i]; 564 sp->types[sp->timecnt] = 565 sp->typecnt + 566 ts.types[i]; 567 ++sp->timecnt; 568 ++i; 569 } 570 sp->ttis[sp->typecnt++] = ts.ttis[0]; 571 sp->ttis[sp->typecnt++] = ts.ttis[1]; 572 } 573 } 574 sp->goback = sp->goahead = FALSE; 575 if (sp->timecnt > 1) { 576 for (i = 1; i < sp->timecnt; ++i) 577 if (typesequiv(sp, sp->types[i], sp->types[0]) && 578 differ_by_repeat(sp->ats[i], sp->ats[0])) { 579 sp->goback = TRUE; 580 break; 581 } 582 for (i = sp->timecnt - 2; i >= 0; --i) 583 if (typesequiv(sp, sp->types[sp->timecnt - 1], 584 sp->types[i]) && 585 differ_by_repeat(sp->ats[sp->timecnt - 1], 586 sp->ats[i])) { 587 sp->goahead = TRUE; 588 break; 589 } 590 } 591 return 0; 592 } 593 594 static int 595 typesequiv(const struct state * const sp, const int a, const int b) 596 { 597 int result; 598 599 if (sp == NULL || 600 a < 0 || a >= sp->typecnt || 601 b < 0 || b >= sp->typecnt) 602 result = FALSE; 603 else { 604 const struct ttinfo * ap = &sp->ttis[a]; 605 const struct ttinfo * bp = &sp->ttis[b]; 606 result = ap->tt_gmtoff == bp->tt_gmtoff && 607 ap->tt_isdst == bp->tt_isdst && 608 ap->tt_ttisstd == bp->tt_ttisstd && 609 ap->tt_ttisgmt == bp->tt_ttisgmt && 610 strcmp(&sp->chars[ap->tt_abbrind], 611 &sp->chars[bp->tt_abbrind]) == 0; 612 } 613 return result; 614 } 615 616 static const int mon_lengths[2][MONSPERYEAR] = { 617 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, 618 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } 619 }; 620 621 static const int year_lengths[2] = { 622 DAYSPERNYEAR, DAYSPERLYEAR 623 }; 624 625 /* 626 ** Given a pointer into a time zone string, scan until a character that is not 627 ** a valid character in a zone name is found. Return a pointer to that 628 ** character. 629 */ 630 631 static const char * 632 getzname(const char *strp) 633 { 634 char c; 635 636 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && 637 c != '+') 638 ++strp; 639 return strp; 640 } 641 642 /* 643 ** Given a pointer into an extended time zone string, scan until the ending 644 ** delimiter of the zone name is located. Return a pointer to the delimiter. 645 ** 646 ** As with getzname above, the legal character set is actually quite 647 ** restricted, with other characters producing undefined results. 648 ** We don't do any checking here; checking is done later in common-case code. 649 */ 650 651 static const char * 652 getqzname(const char *strp, const int delim) 653 { 654 int c; 655 656 while ((c = *strp) != '\0' && c != delim) 657 ++strp; 658 return strp; 659 } 660 661 /* 662 ** Given a pointer into a time zone string, extract a number from that string. 663 ** Check that the number is within a specified range; if it is not, return 664 ** NULL. 665 ** Otherwise, return a pointer to the first character not part of the number. 666 */ 667 668 static const char * 669 getnum(const char *strp, int * const nump, const int min, const int max) 670 { 671 char c; 672 int num; 673 674 if (strp == NULL || !is_digit(c = *strp)) 675 return NULL; 676 num = 0; 677 do { 678 num = num * 10 + (c - '0'); 679 if (num > max) 680 return NULL; /* illegal value */ 681 c = *++strp; 682 } while (is_digit(c)); 683 if (num < min) 684 return NULL; /* illegal value */ 685 *nump = num; 686 return strp; 687 } 688 689 /* 690 ** Given a pointer into a time zone string, extract a number of seconds, 691 ** in hh[:mm[:ss]] form, from the string. 692 ** If any error occurs, return NULL. 693 ** Otherwise, return a pointer to the first character not part of the number 694 ** of seconds. 695 */ 696 697 static const char * 698 getsecs(const char *strp, long * const secsp) 699 { 700 int num; 701 702 /* 703 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like 704 ** "M10.4.6/26", which does not conform to Posix, 705 ** but which specifies the equivalent of 706 ** ``02:00 on the first Sunday on or after 23 Oct''. 707 */ 708 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); 709 if (strp == NULL) 710 return NULL; 711 *secsp = num * (long) SECSPERHOUR; 712 if (*strp == ':') { 713 ++strp; 714 strp = getnum(strp, &num, 0, MINSPERHOUR - 1); 715 if (strp == NULL) 716 return NULL; 717 *secsp += num * SECSPERMIN; 718 if (*strp == ':') { 719 ++strp; 720 /* `SECSPERMIN' allows for leap seconds. */ 721 strp = getnum(strp, &num, 0, SECSPERMIN); 722 if (strp == NULL) 723 return NULL; 724 *secsp += num; 725 } 726 } 727 return strp; 728 } 729 730 /* 731 ** Given a pointer into a time zone string, extract an offset, in 732 ** [+-]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 time. 735 */ 736 737 static const char * 738 getoffset(const char *strp, long * const offsetp) 739 { 740 int neg = 0; 741 742 if (*strp == '-') { 743 neg = 1; 744 ++strp; 745 } else if (*strp == '+') 746 ++strp; 747 strp = getsecs(strp, offsetp); 748 if (strp == NULL) 749 return NULL; /* illegal time */ 750 if (neg) 751 *offsetp = -*offsetp; 752 return strp; 753 } 754 755 /* 756 ** Given a pointer into a time zone string, extract a rule in the form 757 ** date[/time]. See POSIX section 8 for the format of "date" and "time". 758 ** If a valid rule is not found, return NULL. 759 ** Otherwise, return a pointer to the first character not part of the rule. 760 */ 761 762 static const char * 763 getrule(const char *strp, struct rule * const rulep) 764 { 765 if (*strp == 'J') { 766 /* 767 ** Julian day. 768 */ 769 rulep->r_type = JULIAN_DAY; 770 ++strp; 771 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); 772 } else if (*strp == 'M') { 773 /* 774 ** Month, week, day. 775 */ 776 rulep->r_type = MONTH_NTH_DAY_OF_WEEK; 777 ++strp; 778 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); 779 if (strp == NULL) 780 return NULL; 781 if (*strp++ != '.') 782 return NULL; 783 strp = getnum(strp, &rulep->r_week, 1, 5); 784 if (strp == NULL) 785 return NULL; 786 if (*strp++ != '.') 787 return NULL; 788 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); 789 } else if (is_digit(*strp)) { 790 /* 791 ** Day of year. 792 */ 793 rulep->r_type = DAY_OF_YEAR; 794 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); 795 } else return NULL; /* invalid format */ 796 if (strp == NULL) 797 return NULL; 798 if (*strp == '/') { 799 /* 800 ** Time specified. 801 */ 802 ++strp; 803 strp = getsecs(strp, &rulep->r_time); 804 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ 805 return strp; 806 } 807 808 /* 809 ** Given the Epoch-relative time of January 1, 00:00:00 UTC, in a year, the 810 ** year, a rule, and the offset from UTC at the time that rule takes effect, 811 ** calculate the Epoch-relative time that rule takes effect. 812 */ 813 814 static time_t 815 transtime(const time_t janfirst, const int year, 816 const struct rule * const rulep, const long offset) 817 { 818 int leapyear; 819 time_t value; 820 int i; 821 int d, m1, yy0, yy1, yy2, dow; 822 823 INITIALIZE(value); 824 leapyear = isleap(year); 825 switch (rulep->r_type) { 826 827 case JULIAN_DAY: 828 /* 829 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap 830 ** years. 831 ** In non-leap years, or if the day number is 59 or less, just 832 ** add SECSPERDAY times the day number-1 to the time of 833 ** January 1, midnight, to get the day. 834 */ 835 value = janfirst + (rulep->r_day - 1) * SECSPERDAY; 836 if (leapyear && rulep->r_day >= 60) 837 value += SECSPERDAY; 838 break; 839 840 case DAY_OF_YEAR: 841 /* 842 ** n - day of year. 843 ** Just add SECSPERDAY times the day number to the time of 844 ** January 1, midnight, to get the day. 845 */ 846 value = janfirst + rulep->r_day * SECSPERDAY; 847 break; 848 849 case MONTH_NTH_DAY_OF_WEEK: 850 /* 851 ** Mm.n.d - nth "dth day" of month m. 852 */ 853 value = janfirst; 854 for (i = 0; i < rulep->r_mon - 1; ++i) 855 value += mon_lengths[leapyear][i] * SECSPERDAY; 856 857 /* 858 ** Use Zeller's Congruence to get day-of-week of first day of 859 ** month. 860 */ 861 m1 = (rulep->r_mon + 9) % 12 + 1; 862 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; 863 yy1 = yy0 / 100; 864 yy2 = yy0 % 100; 865 dow = ((26 * m1 - 2) / 10 + 866 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; 867 if (dow < 0) 868 dow += DAYSPERWEEK; 869 870 /* 871 ** "dow" is the day-of-week of the first day of the month. Get 872 ** the day-of-month (zero-origin) of the first "dow" day of the 873 ** month. 874 */ 875 d = rulep->r_day - dow; 876 if (d < 0) 877 d += DAYSPERWEEK; 878 for (i = 1; i < rulep->r_week; ++i) { 879 if (d + DAYSPERWEEK >= 880 mon_lengths[leapyear][rulep->r_mon - 1]) 881 break; 882 d += DAYSPERWEEK; 883 } 884 885 /* 886 ** "d" is the day-of-month (zero-origin) of the day we want. 887 */ 888 value += d * SECSPERDAY; 889 break; 890 } 891 892 /* 893 ** "value" is the Epoch-relative time of 00:00:00 UTC on the day in 894 ** question. To get the Epoch-relative time of the specified local 895 ** time on that day, add the transition time and the current offset 896 ** from UTC. 897 */ 898 return value + rulep->r_time + offset; 899 } 900 901 /* 902 ** Given a POSIX section 8-style TZ string, fill in the rule tables as 903 ** appropriate. 904 */ 905 906 static int 907 tzparse(const char *name, struct state * const sp, const int lastditch) 908 { 909 const char * stdname; 910 const char * dstname; 911 size_t stdlen; 912 size_t dstlen; 913 long stdoffset; 914 long dstoffset; 915 time_t * atp; 916 unsigned char * typep; 917 char * cp; 918 int load_result; 919 920 INITIALIZE(dstname); 921 stdname = name; 922 if (lastditch) { 923 stdlen = strlen(name); /* length of standard zone name */ 924 name += stdlen; 925 if (stdlen >= sizeof sp->chars) 926 stdlen = (sizeof sp->chars) - 1; 927 stdoffset = 0; 928 } else { 929 if (*name == '<') { 930 name++; 931 stdname = name; 932 name = getqzname(name, '>'); 933 if (*name != '>') 934 return (-1); 935 stdlen = name - stdname; 936 name++; 937 } else { 938 name = getzname(name); 939 stdlen = name - stdname; 940 } 941 if (*name == '\0') 942 return -1; 943 name = getoffset(name, &stdoffset); 944 if (name == NULL) 945 return -1; 946 } 947 load_result = tzload(TZDEFRULES, sp, FALSE); 948 if (load_result != 0) 949 sp->leapcnt = 0; /* so, we're off a little */ 950 if (*name != '\0') { 951 if (*name == '<') { 952 dstname = ++name; 953 name = getqzname(name, '>'); 954 if (*name != '>') 955 return -1; 956 dstlen = name - dstname; 957 name++; 958 } else { 959 dstname = name; 960 name = getzname(name); 961 dstlen = name - dstname; /* length of DST zone name */ 962 } 963 if (*name != '\0' && *name != ',' && *name != ';') { 964 name = getoffset(name, &dstoffset); 965 if (name == NULL) 966 return -1; 967 } else dstoffset = stdoffset - SECSPERHOUR; 968 if (*name == '\0' && load_result != 0) 969 name = TZDEFRULESTRING; 970 if (*name == ',' || *name == ';') { 971 struct rule start; 972 struct rule end; 973 int year; 974 time_t janfirst; 975 time_t starttime; 976 time_t endtime; 977 978 ++name; 979 if ((name = getrule(name, &start)) == NULL) 980 return -1; 981 if (*name++ != ',') 982 return -1; 983 if ((name = getrule(name, &end)) == NULL) 984 return -1; 985 if (*name != '\0') 986 return -1; 987 sp->typecnt = 2; /* standard time and DST */ 988 /* 989 ** Two transitions per year, from EPOCH_YEAR forward. 990 */ 991 sp->ttis[0].tt_gmtoff = -dstoffset; 992 sp->ttis[0].tt_isdst = 1; 993 sp->ttis[0].tt_abbrind = stdlen + 1; 994 sp->ttis[1].tt_gmtoff = -stdoffset; 995 sp->ttis[1].tt_isdst = 0; 996 sp->ttis[1].tt_abbrind = 0; 997 atp = sp->ats; 998 typep = sp->types; 999 janfirst = 0; 1000 sp->timecnt = 0; 1001 for (year = EPOCH_YEAR; 1002 sp->timecnt + 2 <= TZ_MAX_TIMES; 1003 ++year) { 1004 time_t newfirst; 1005 1006 starttime = transtime(janfirst, year, &start, 1007 stdoffset); 1008 endtime = transtime(janfirst, year, &end, 1009 dstoffset); 1010 if (starttime > endtime) { 1011 *atp++ = endtime; 1012 *typep++ = 1; /* DST ends */ 1013 *atp++ = starttime; 1014 *typep++ = 0; /* DST begins */ 1015 } else { 1016 *atp++ = starttime; 1017 *typep++ = 0; /* DST begins */ 1018 *atp++ = endtime; 1019 *typep++ = 1; /* DST ends */ 1020 } 1021 sp->timecnt += 2; 1022 newfirst = janfirst; 1023 newfirst += year_lengths[isleap(year)] * 1024 SECSPERDAY; 1025 if (newfirst <= janfirst) 1026 break; 1027 janfirst = newfirst; 1028 } 1029 } else { 1030 long theirstdoffset; 1031 long theirdstoffset; 1032 long theiroffset; 1033 int isdst; 1034 int i; 1035 int j; 1036 1037 if (*name != '\0') 1038 return -1; 1039 /* 1040 ** Initial values of theirstdoffset and theirdstoffset. 1041 */ 1042 theirstdoffset = 0; 1043 for (i = 0; i < sp->timecnt; ++i) { 1044 j = sp->types[i]; 1045 if (!sp->ttis[j].tt_isdst) { 1046 theirstdoffset = 1047 -sp->ttis[j].tt_gmtoff; 1048 break; 1049 } 1050 } 1051 theirdstoffset = 0; 1052 for (i = 0; i < sp->timecnt; ++i) { 1053 j = sp->types[i]; 1054 if (sp->ttis[j].tt_isdst) { 1055 theirdstoffset = 1056 -sp->ttis[j].tt_gmtoff; 1057 break; 1058 } 1059 } 1060 /* 1061 ** Initially we're assumed to be in standard time. 1062 */ 1063 isdst = FALSE; 1064 theiroffset = theirstdoffset; 1065 /* 1066 ** Now juggle transition times and types 1067 ** tracking offsets as you do. 1068 */ 1069 for (i = 0; i < sp->timecnt; ++i) { 1070 j = sp->types[i]; 1071 sp->types[i] = sp->ttis[j].tt_isdst; 1072 if (sp->ttis[j].tt_ttisgmt) { 1073 /* No adjustment to transition time */ 1074 } else { 1075 /* 1076 ** If summer time is in effect, and the 1077 ** transition time was not specified as 1078 ** standard time, add the summer time 1079 ** offset to the transition time; 1080 ** otherwise, add the standard time 1081 ** offset to the transition time. 1082 */ 1083 /* 1084 ** Transitions from DST to DDST 1085 ** will effectively disappear since 1086 ** POSIX provides for only one DST 1087 ** offset. 1088 */ 1089 if (isdst && !sp->ttis[j].tt_ttisstd) { 1090 sp->ats[i] += dstoffset - 1091 theirdstoffset; 1092 } else { 1093 sp->ats[i] += stdoffset - 1094 theirstdoffset; 1095 } 1096 } 1097 theiroffset = -sp->ttis[j].tt_gmtoff; 1098 if (sp->ttis[j].tt_isdst) 1099 theirdstoffset = theiroffset; 1100 else theirstdoffset = theiroffset; 1101 } 1102 /* 1103 ** Finally, fill in ttis. 1104 ** ttisstd and ttisgmt need not be handled. 1105 */ 1106 sp->ttis[0].tt_gmtoff = -stdoffset; 1107 sp->ttis[0].tt_isdst = FALSE; 1108 sp->ttis[0].tt_abbrind = 0; 1109 sp->ttis[1].tt_gmtoff = -dstoffset; 1110 sp->ttis[1].tt_isdst = TRUE; 1111 sp->ttis[1].tt_abbrind = stdlen + 1; 1112 sp->typecnt = 2; 1113 } 1114 } else { 1115 dstlen = 0; 1116 sp->typecnt = 1; /* only standard time */ 1117 sp->timecnt = 0; 1118 sp->ttis[0].tt_gmtoff = -stdoffset; 1119 sp->ttis[0].tt_isdst = 0; 1120 sp->ttis[0].tt_abbrind = 0; 1121 } 1122 sp->charcnt = stdlen + 1; 1123 if (dstlen != 0) 1124 sp->charcnt += dstlen + 1; 1125 if ((size_t) sp->charcnt > sizeof sp->chars) 1126 return -1; 1127 cp = sp->chars; 1128 strncpy(cp, stdname, stdlen); 1129 cp += stdlen; 1130 *cp++ = '\0'; 1131 if (dstlen != 0) { 1132 strncpy(cp, dstname, dstlen); 1133 *(cp + dstlen) = '\0'; 1134 } 1135 return 0; 1136 } 1137 1138 static void 1139 gmtload(struct state * const sp) 1140 { 1141 if (tzload(gmt, sp, TRUE) != 0) 1142 tzparse(gmt, sp, TRUE); 1143 } 1144 1145 static void 1146 tzsetwall_basic(void) 1147 { 1148 if (lcl_is_set < 0) 1149 return; 1150 lcl_is_set = -1; 1151 1152 #ifdef ALL_STATE 1153 if (lclptr == NULL) { 1154 lclptr = (struct state *) malloc(sizeof *lclptr); 1155 if (lclptr == NULL) { 1156 settzname(); /* all we can do */ 1157 return; 1158 } 1159 } 1160 #endif /* defined ALL_STATE */ 1161 if (tzload((char *) NULL, lclptr, TRUE) != 0) 1162 gmtload(lclptr); 1163 settzname(); 1164 } 1165 1166 void 1167 tzsetwall(void) 1168 { 1169 _MUTEX_LOCK(&lcl_mutex); 1170 tzsetwall_basic(); 1171 _MUTEX_UNLOCK(&lcl_mutex); 1172 } 1173 1174 static void 1175 tzset_basic(void) 1176 { 1177 const char * name; 1178 1179 name = getenv("TZ"); 1180 if (name == NULL) { 1181 tzsetwall(); 1182 return; 1183 } 1184 1185 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) 1186 return; 1187 lcl_is_set = strlen(name) < sizeof lcl_TZname; 1188 if (lcl_is_set) 1189 strcpy(lcl_TZname, name); 1190 1191 #ifdef ALL_STATE 1192 if (lclptr == NULL) { 1193 lclptr = (struct state *) malloc(sizeof *lclptr); 1194 if (lclptr == NULL) { 1195 settzname(); /* all we can do */ 1196 return; 1197 } 1198 } 1199 #endif /* defined ALL_STATE */ 1200 if (*name == '\0') { 1201 /* 1202 ** User wants it fast rather than right. 1203 */ 1204 lclptr->leapcnt = 0; /* so, we're off a little */ 1205 lclptr->timecnt = 0; 1206 lclptr->typecnt = 0; 1207 lclptr->ttis[0].tt_isdst = 0; 1208 lclptr->ttis[0].tt_gmtoff = 0; 1209 lclptr->ttis[0].tt_abbrind = 0; 1210 strcpy(lclptr->chars, gmt); 1211 } else if (tzload(name, lclptr, TRUE) != 0) 1212 if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0) 1213 gmtload(lclptr); 1214 settzname(); 1215 } 1216 1217 void 1218 tzset(void) 1219 { 1220 _MUTEX_LOCK(&lcl_mutex); 1221 tzset_basic(); 1222 _MUTEX_UNLOCK(&lcl_mutex); 1223 } 1224 1225 /* 1226 ** The easy way to behave "as if no library function calls" localtime 1227 ** is to not call it--so we drop its guts into "localsub", which can be 1228 ** freely called. (And no, the PANS doesn't require the above behavior-- 1229 ** but it *is* desirable.) 1230 ** 1231 ** The unused offset argument is for the benefit of mktime variants. 1232 */ 1233 1234 /*ARGSUSED*/ 1235 static struct tm * 1236 localsub(const time_t * const timep, const long offset __unused, 1237 struct tm * const tmp) 1238 { 1239 struct state * sp; 1240 const struct ttinfo * ttisp; 1241 int i; 1242 struct tm * result; 1243 const time_t t = *timep; 1244 1245 sp = lclptr; 1246 #ifdef ALL_STATE 1247 if (sp == NULL) 1248 return gmtsub(timep, offset, tmp); 1249 #endif /* defined ALL_STATE */ 1250 if ((sp->goback && t < sp->ats[0]) || 1251 (sp->goahead && t > sp->ats[sp->timecnt - 1])) { 1252 time_t newt = t; 1253 time_t seconds; 1254 time_t tcycles; 1255 int_fast64_t icycles; 1256 1257 if (t < sp->ats[0]) 1258 seconds = sp->ats[0] - t; 1259 else seconds = t - sp->ats[sp->timecnt - 1]; 1260 --seconds; 1261 tcycles = seconds / YEARSPERREPEAT / AVGSECSPERYEAR; 1262 ++tcycles; 1263 icycles = tcycles; 1264 if (tcycles - icycles >= 1 || icycles - tcycles >= 1) 1265 return NULL; 1266 seconds = icycles; 1267 seconds *= YEARSPERREPEAT; 1268 seconds *= AVGSECSPERYEAR; 1269 if (t < sp->ats[0]) 1270 newt += seconds; 1271 else newt -= seconds; 1272 if (newt < sp->ats[0] || 1273 newt > sp->ats[sp->timecnt - 1]) 1274 return NULL; /* "cannot happen" */ 1275 result = localsub(&newt, offset, tmp); 1276 if (result == tmp) { 1277 time_t newy; 1278 1279 newy = tmp->tm_year; 1280 if (t < sp->ats[0]) 1281 newy -= icycles * YEARSPERREPEAT; 1282 else newy += icycles * YEARSPERREPEAT; 1283 tmp->tm_year = newy; 1284 if (tmp->tm_year != newy) 1285 return NULL; 1286 } 1287 return result; 1288 } 1289 if (sp->timecnt == 0 || t < sp->ats[0]) { 1290 i = 0; 1291 while (sp->ttis[i].tt_isdst) 1292 if (++i >= sp->typecnt) { 1293 i = 0; 1294 break; 1295 } 1296 } else { 1297 int lo = 1; 1298 int hi = sp->timecnt; 1299 1300 while (lo < hi) { 1301 int mid = (lo + hi) >> 1; 1302 1303 if (t < sp->ats[mid]) 1304 hi = mid; 1305 else lo = mid + 1; 1306 } 1307 i = (int) sp->types[lo - 1]; 1308 } 1309 ttisp = &sp->ttis[i]; 1310 /* 1311 ** To get (wrong) behavior that's compatible with System V Release 2.0 1312 ** you'd replace the statement below with 1313 ** t += ttisp->tt_gmtoff; 1314 ** timesub(&t, 0L, sp, tmp); 1315 */ 1316 result = timesub(&t, ttisp->tt_gmtoff, sp, tmp); 1317 tmp->tm_isdst = ttisp->tt_isdst; 1318 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind]; 1319 #ifdef TM_ZONE 1320 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind]; 1321 #endif /* defined TM_ZONE */ 1322 return result; 1323 } 1324 1325 struct tm * 1326 localtime_r(const time_t * const timep, struct tm *p_tm) 1327 { 1328 _MUTEX_LOCK(&lcl_mutex); 1329 tzset(); 1330 localsub(timep, 0L, p_tm); 1331 _MUTEX_UNLOCK(&lcl_mutex); 1332 return(p_tm); 1333 } 1334 1335 struct tm * 1336 localtime(const time_t * const timep) 1337 { 1338 static pthread_mutex_t localtime_mutex = PTHREAD_MUTEX_INITIALIZER; 1339 static pthread_key_t localtime_key = -1; 1340 struct tm *p_tm; 1341 1342 if (__isthreaded != 0) { 1343 _pthread_mutex_lock(&localtime_mutex); 1344 if (localtime_key < 0) { 1345 if (_pthread_key_create(&localtime_key, free) < 0) { 1346 _pthread_mutex_unlock(&localtime_mutex); 1347 return(NULL); 1348 } 1349 } 1350 _pthread_mutex_unlock(&localtime_mutex); 1351 p_tm = _pthread_getspecific(localtime_key); 1352 if (p_tm == NULL) { 1353 if ((p_tm = (struct tm *)malloc(sizeof(struct tm))) 1354 == NULL) 1355 return(NULL); 1356 _pthread_setspecific(localtime_key, p_tm); 1357 } 1358 _pthread_mutex_lock(&lcl_mutex); 1359 tzset(); 1360 localsub(timep, 0L, p_tm); 1361 _pthread_mutex_unlock(&lcl_mutex); 1362 return(p_tm); 1363 } else { 1364 tzset(); 1365 localsub(timep, 0L, &tm); 1366 return(&tm); 1367 } 1368 } 1369 1370 /* 1371 ** gmtsub is to gmtime as localsub is to localtime. 1372 */ 1373 1374 static struct tm * 1375 gmtsub(const time_t * const timep, const long offset, struct tm * const tmp) 1376 { 1377 struct tm * result; 1378 1379 _MUTEX_LOCK(&gmt_mutex); 1380 if (!gmt_is_set) { 1381 gmt_is_set = TRUE; 1382 #ifdef ALL_STATE 1383 gmtptr = (struct state *) malloc(sizeof *gmtptr); 1384 if (gmtptr != NULL) 1385 #endif /* defined ALL_STATE */ 1386 gmtload(gmtptr); 1387 } 1388 _MUTEX_UNLOCK(&gmt_mutex); 1389 result = timesub(timep, offset, gmtptr, tmp); 1390 #ifdef TM_ZONE 1391 /* 1392 ** Could get fancy here and deliver something such as 1393 ** "UTC+xxxx" or "UTC-xxxx" if offset is non-zero, 1394 ** but this is no time for a treasure hunt. 1395 */ 1396 if (offset != 0) 1397 tmp->TM_ZONE = wildabbr; 1398 else { 1399 #ifdef ALL_STATE 1400 if (gmtptr == NULL) 1401 tmp->TM_ZONE = gmt; 1402 else tmp->TM_ZONE = gmtptr->chars; 1403 #endif /* defined ALL_STATE */ 1404 #ifndef ALL_STATE 1405 tmp->TM_ZONE = gmtptr->chars; 1406 #endif /* State Farm */ 1407 } 1408 #endif /* defined TM_ZONE */ 1409 return result; 1410 } 1411 1412 struct tm * 1413 gmtime(const time_t * const timep) 1414 { 1415 static pthread_mutex_t gmtime_mutex = PTHREAD_MUTEX_INITIALIZER; 1416 static pthread_key_t gmtime_key = -1; 1417 struct tm *p_tm; 1418 1419 if (__isthreaded != 0) { 1420 _pthread_mutex_lock(&gmtime_mutex); 1421 if (gmtime_key < 0) { 1422 if (_pthread_key_create(&gmtime_key, free) < 0) { 1423 _pthread_mutex_unlock(&gmtime_mutex); 1424 return(NULL); 1425 } 1426 } 1427 _pthread_mutex_unlock(&gmtime_mutex); 1428 /* 1429 * Changed to follow POSIX.1 threads standard, which 1430 * is what BSD currently has. 1431 */ 1432 if ((p_tm = _pthread_getspecific(gmtime_key)) == NULL) { 1433 if ((p_tm = (struct tm *)malloc(sizeof(struct tm))) 1434 == NULL) { 1435 return(NULL); 1436 } 1437 _pthread_setspecific(gmtime_key, p_tm); 1438 } 1439 return gmtsub(timep, 0L, p_tm); 1440 } else { 1441 return gmtsub(timep, 0L, &tm); 1442 } 1443 } 1444 1445 struct tm * 1446 gmtime_r(const time_t * timep, struct tm * tmp) 1447 { 1448 return gmtsub(timep, 0L, tmp); 1449 } 1450 1451 #ifdef STD_INSPIRED 1452 1453 struct tm * 1454 offtime(const time_t * const timep, const long offset) 1455 { 1456 return gmtsub(timep, offset, &tm); 1457 } 1458 1459 #endif /* defined STD_INSPIRED */ 1460 1461 /* 1462 ** Return the number of leap years through the end of the given year 1463 ** where, to make the math easy, the answer for year zero is defined as zero. 1464 */ 1465 1466 static int 1467 leaps_thru_end_of(const int y) 1468 { 1469 return (y >= 0) ? (y / 4 - y / 100 + y / 400) : 1470 -(leaps_thru_end_of(-(y + 1)) + 1); 1471 } 1472 1473 static struct tm * 1474 timesub(const time_t * const timep, const long offset, 1475 const struct state * const sp, struct tm * const tmp) 1476 { 1477 const struct lsinfo * lp; 1478 time_t tdays; 1479 int idays; /* unsigned would be so 2003 */ 1480 long rem; 1481 int y; 1482 int yleap; 1483 const int * ip; 1484 long corr; 1485 int hit; 1486 int i; 1487 1488 corr = 0; 1489 hit = 0; 1490 #ifdef ALL_STATE 1491 i = (sp == NULL) ? 0 : sp->leapcnt; 1492 #endif /* defined ALL_STATE */ 1493 #ifndef ALL_STATE 1494 i = sp->leapcnt; 1495 #endif /* State Farm */ 1496 while (--i >= 0) { 1497 lp = &sp->lsis[i]; 1498 if (*timep >= lp->ls_trans) { 1499 if (*timep == lp->ls_trans) { 1500 hit = ((i == 0 && lp->ls_corr > 0) || 1501 lp->ls_corr > sp->lsis[i - 1].ls_corr); 1502 if (hit) 1503 while (i > 0 && 1504 sp->lsis[i].ls_trans == 1505 sp->lsis[i - 1].ls_trans + 1 && 1506 sp->lsis[i].ls_corr == 1507 sp->lsis[i - 1].ls_corr + 1) { 1508 ++hit; 1509 --i; 1510 } 1511 } 1512 corr = lp->ls_corr; 1513 break; 1514 } 1515 } 1516 y = EPOCH_YEAR; 1517 tdays = *timep / SECSPERDAY; 1518 rem = *timep - tdays * SECSPERDAY; 1519 while (tdays < 0 || tdays >= year_lengths[isleap(y)]) { 1520 int newy; 1521 time_t tdelta; 1522 int idelta; 1523 int leapdays; 1524 1525 tdelta = tdays / DAYSPERLYEAR; 1526 idelta = tdelta; 1527 if (tdelta - idelta >= 1 || idelta - tdelta >= 1) 1528 return NULL; 1529 if (idelta == 0) 1530 idelta = (tdays < 0) ? -1 : 1; 1531 newy = y; 1532 if (increment_overflow(&newy, idelta)) 1533 return NULL; 1534 leapdays = leaps_thru_end_of(newy - 1) - 1535 leaps_thru_end_of(y - 1); 1536 tdays -= ((time_t) newy - y) * DAYSPERNYEAR; 1537 tdays -= leapdays; 1538 y = newy; 1539 } 1540 { 1541 long seconds; 1542 1543 seconds = tdays * SECSPERDAY + 0.5; 1544 tdays = seconds / SECSPERDAY; 1545 rem += seconds - tdays * SECSPERDAY; 1546 } 1547 /* 1548 ** Given the range, we can now fearlessly cast... 1549 */ 1550 idays = tdays; 1551 rem += offset - corr; 1552 while (rem < 0) { 1553 rem += SECSPERDAY; 1554 --idays; 1555 } 1556 while (rem >= SECSPERDAY) { 1557 rem -= SECSPERDAY; 1558 ++idays; 1559 } 1560 while (idays < 0) { 1561 if (increment_overflow(&y, -1)) 1562 return NULL; 1563 idays += year_lengths[isleap(y)]; 1564 } 1565 while (idays >= year_lengths[isleap(y)]) { 1566 idays -= year_lengths[isleap(y)]; 1567 if (increment_overflow(&y, 1)) 1568 return NULL; 1569 } 1570 tmp->tm_year = y; 1571 if (increment_overflow(&tmp->tm_year, -TM_YEAR_BASE)) 1572 return NULL; 1573 tmp->tm_yday = idays; 1574 /* 1575 ** The "extra" mods below avoid overflow problems. 1576 */ 1577 tmp->tm_wday = EPOCH_WDAY + 1578 ((y - EPOCH_YEAR) % DAYSPERWEEK) * 1579 (DAYSPERNYEAR % DAYSPERWEEK) + 1580 leaps_thru_end_of(y - 1) - 1581 leaps_thru_end_of(EPOCH_YEAR - 1) + 1582 idays; 1583 tmp->tm_wday %= DAYSPERWEEK; 1584 if (tmp->tm_wday < 0) 1585 tmp->tm_wday += DAYSPERWEEK; 1586 tmp->tm_hour = (int) (rem / SECSPERHOUR); 1587 rem %= SECSPERHOUR; 1588 tmp->tm_min = (int) (rem / SECSPERMIN); 1589 /* 1590 ** A positive leap second requires a special 1591 ** representation. This uses "... ??:59:60" et seq. 1592 */ 1593 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit; 1594 ip = mon_lengths[isleap(y)]; 1595 for (tmp->tm_mon = 0; idays >= ip[tmp->tm_mon]; ++(tmp->tm_mon)) 1596 idays -= ip[tmp->tm_mon]; 1597 tmp->tm_mday = (int) (idays + 1); 1598 tmp->tm_isdst = 0; 1599 #ifdef TM_GMTOFF 1600 tmp->TM_GMTOFF = offset; 1601 #endif /* defined TM_GMTOFF */ 1602 return tmp; 1603 } 1604 1605 char * 1606 ctime(const time_t * const timep) 1607 { 1608 /* 1609 ** Section 4.12.3.2 of X3.159-1989 requires that 1610 ** The ctime function converts the calendar time pointed to by timer 1611 ** to local time in the form of a string. It is equivalent to 1612 ** asctime(localtime(timer)) 1613 */ 1614 return asctime(localtime(timep)); 1615 } 1616 1617 char * 1618 ctime_r(const time_t * const timep, char *buf) 1619 { 1620 struct tm mytm; 1621 return asctime_r(localtime_r(timep, &mytm), buf); 1622 } 1623 1624 /* 1625 ** Adapted from code provided by Robert Elz, who writes: 1626 ** The "best" way to do mktime I think is based on an idea of Bob 1627 ** Kridle's (so its said...) from a long time ago. 1628 ** It does a binary search of the time_t space. Since time_t's are 1629 ** just 32 bits, its a max of 32 iterations (even at 64 bits it 1630 ** would still be very reasonable). 1631 */ 1632 1633 #ifndef WRONG 1634 #define WRONG (-1) 1635 #endif /* !defined WRONG */ 1636 1637 /* 1638 ** Simplified normalize logic courtesy Paul Eggert. 1639 */ 1640 1641 static int 1642 increment_overflow(int *number, int delta) 1643 { 1644 int number0; 1645 1646 number0 = *number; 1647 *number += delta; 1648 return (*number < number0) != (delta < 0); 1649 } 1650 1651 static int 1652 long_increment_overflow(long *number, int delta) 1653 { 1654 long number0; 1655 1656 number0 = *number; 1657 *number += delta; 1658 return (*number < number0) != (delta < 0); 1659 } 1660 1661 static int 1662 normalize_overflow(int * const tensptr, int * const unitsptr, const int base) 1663 { 1664 int tensdelta; 1665 1666 tensdelta = (*unitsptr >= 0) ? 1667 (*unitsptr / base) : 1668 (-1 - (-1 - *unitsptr) / base); 1669 *unitsptr -= tensdelta * base; 1670 return increment_overflow(tensptr, tensdelta); 1671 } 1672 1673 static int 1674 long_normalize_overflow(long * const tensptr, int * const unitsptr, 1675 const int base) 1676 { 1677 int tensdelta; 1678 1679 tensdelta = (*unitsptr >= 0) ? 1680 (*unitsptr / base) : 1681 (-1 - (-1 - *unitsptr) / base); 1682 *unitsptr -= tensdelta * base; 1683 return long_increment_overflow(tensptr, tensdelta); 1684 } 1685 1686 static int 1687 tmcomp(const struct tm * const atmp, const struct tm * const btmp) 1688 { 1689 int result; 1690 1691 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 && 1692 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 && 1693 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && 1694 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && 1695 (result = (atmp->tm_min - btmp->tm_min)) == 0) 1696 result = atmp->tm_sec - btmp->tm_sec; 1697 return result; 1698 } 1699 1700 static time_t 1701 time2sub(struct tm * const tmp, 1702 struct tm * (* const funcp)(const time_t *, long, struct tm *), 1703 const long offset, int * const okayp, const int do_norm_secs) 1704 { 1705 const struct state * sp; 1706 int dir; 1707 int i, j; 1708 int saved_seconds; 1709 long li; 1710 time_t lo; 1711 time_t hi; 1712 long y; 1713 time_t newt; 1714 time_t t; 1715 struct tm yourtm, mytm; 1716 1717 *okayp = FALSE; 1718 yourtm = *tmp; 1719 if (do_norm_secs) { 1720 if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec, 1721 SECSPERMIN)) 1722 return WRONG; 1723 } 1724 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) 1725 return WRONG; 1726 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) 1727 return WRONG; 1728 y = yourtm.tm_year; 1729 if (long_normalize_overflow(&y, &yourtm.tm_mon, MONSPERYEAR)) 1730 return WRONG; 1731 /* 1732 ** Turn y into an actual year number for now. 1733 ** It is converted back to an offset from TM_YEAR_BASE later. 1734 */ 1735 if (long_increment_overflow(&y, TM_YEAR_BASE)) 1736 return WRONG; 1737 while (yourtm.tm_mday <= 0) { 1738 if (long_increment_overflow(&y, -1)) 1739 return WRONG; 1740 li = y + (1 < yourtm.tm_mon); 1741 yourtm.tm_mday += year_lengths[isleap(li)]; 1742 } 1743 while (yourtm.tm_mday > DAYSPERLYEAR) { 1744 li = y + (1 < yourtm.tm_mon); 1745 yourtm.tm_mday -= year_lengths[isleap(li)]; 1746 if (long_increment_overflow(&y, 1)) 1747 return WRONG; 1748 } 1749 for ( ; ; ) { 1750 i = mon_lengths[isleap(y)][yourtm.tm_mon]; 1751 if (yourtm.tm_mday <= i) 1752 break; 1753 yourtm.tm_mday -= i; 1754 if (++yourtm.tm_mon >= MONSPERYEAR) { 1755 yourtm.tm_mon = 0; 1756 if (long_increment_overflow(&y, 1)) 1757 return WRONG; 1758 } 1759 } 1760 if (long_increment_overflow(&y, -TM_YEAR_BASE)) 1761 return WRONG; 1762 yourtm.tm_year = y; 1763 if (yourtm.tm_year != y) 1764 return WRONG; 1765 if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN) 1766 saved_seconds = 0; 1767 else if (y + TM_YEAR_BASE < EPOCH_YEAR) { 1768 /* 1769 ** We can't set tm_sec to 0, because that might push the 1770 ** time below the minimum representable time. 1771 ** Set tm_sec to 59 instead. 1772 ** This assumes that the minimum representable time is 1773 ** not in the same minute that a leap second was deleted from, 1774 ** which is a safer assumption than using 58 would be. 1775 */ 1776 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) 1777 return WRONG; 1778 saved_seconds = yourtm.tm_sec; 1779 yourtm.tm_sec = SECSPERMIN - 1; 1780 } else { 1781 saved_seconds = yourtm.tm_sec; 1782 yourtm.tm_sec = 0; 1783 } 1784 /* 1785 ** Do a binary search (this works whatever time_t's type is). 1786 */ 1787 if (!TYPE_SIGNED(time_t)) { 1788 lo = 0; 1789 hi = lo - 1; 1790 } else if (!TYPE_INTEGRAL(time_t)) { 1791 if (sizeof(time_t) > sizeof(float)) 1792 hi = (time_t) DBL_MAX; 1793 else hi = (time_t) FLT_MAX; 1794 lo = -hi; 1795 } else { 1796 lo = 1; 1797 for (i = 0; i < (int) TYPE_BIT(time_t) - 1; ++i) 1798 lo *= 2; 1799 hi = -(lo + 1); 1800 } 1801 for ( ; ; ) { 1802 t = lo / 2 + hi / 2; 1803 if (t < lo) 1804 t = lo; 1805 else if (t > hi) 1806 t = hi; 1807 if ((*funcp)(&t, offset, &mytm) == NULL) { 1808 /* 1809 ** Assume that t is too extreme to be represented in 1810 ** a struct tm; arrange things so that it is less 1811 ** extreme on the next pass. 1812 */ 1813 dir = (t > 0) ? 1 : -1; 1814 } else dir = tmcomp(&mytm, &yourtm); 1815 if (dir != 0) { 1816 if (t == lo) { 1817 ++t; 1818 if (t <= lo) 1819 return WRONG; 1820 ++lo; 1821 } else if (t == hi) { 1822 --t; 1823 if (t >= hi) 1824 return WRONG; 1825 --hi; 1826 } 1827 if (lo > hi) 1828 return WRONG; 1829 if (dir > 0) 1830 hi = t; 1831 else lo = t; 1832 continue; 1833 } 1834 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) 1835 break; 1836 /* 1837 ** Right time, wrong type. 1838 ** Hunt for right time, right type. 1839 ** It's okay to guess wrong since the guess 1840 ** gets checked. 1841 */ 1842 sp = (const struct state *) 1843 ((funcp == localsub) ? lclptr : gmtptr); 1844 #ifdef ALL_STATE 1845 if (sp == NULL) 1846 return WRONG; 1847 #endif /* defined ALL_STATE */ 1848 for (i = sp->typecnt - 1; i >= 0; --i) { 1849 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) 1850 continue; 1851 for (j = sp->typecnt - 1; j >= 0; --j) { 1852 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) 1853 continue; 1854 newt = t + sp->ttis[j].tt_gmtoff - 1855 sp->ttis[i].tt_gmtoff; 1856 if ((*funcp)(&newt, offset, &mytm) == NULL) 1857 continue; 1858 if (tmcomp(&mytm, &yourtm) != 0) 1859 continue; 1860 if (mytm.tm_isdst != yourtm.tm_isdst) 1861 continue; 1862 /* 1863 ** We have a match. 1864 */ 1865 t = newt; 1866 goto label; 1867 } 1868 } 1869 return WRONG; 1870 } 1871 label: 1872 newt = t + saved_seconds; 1873 if ((newt < t) != (saved_seconds < 0)) 1874 return WRONG; 1875 t = newt; 1876 if ((*funcp)(&t, offset, tmp)) 1877 *okayp = TRUE; 1878 return t; 1879 } 1880 1881 static time_t 1882 time2(struct tm * const tmp, 1883 struct tm * (* const funcp)(const time_t *, long, struct tm *), 1884 const long offset, int * const okayp) 1885 { 1886 time_t t; 1887 1888 /* 1889 ** First try without normalization of seconds 1890 ** (in case tm_sec contains a value associated with a leap second). 1891 ** If that fails, try with normalization of seconds. 1892 */ 1893 t = time2sub(tmp, funcp, offset, okayp, FALSE); 1894 return *okayp ? t : time2sub(tmp, funcp, offset, okayp, TRUE); 1895 } 1896 1897 static time_t 1898 time1(struct tm * const tmp, 1899 struct tm * (* const funcp)(const time_t *, long, struct tm *), 1900 const long offset) 1901 { 1902 time_t t; 1903 const struct state * sp; 1904 int samei, otheri; 1905 int sameind, otherind; 1906 int i; 1907 int nseen; 1908 int seen[TZ_MAX_TYPES]; 1909 int types[TZ_MAX_TYPES]; 1910 int okay; 1911 1912 if (tmp->tm_isdst > 1) 1913 tmp->tm_isdst = 1; 1914 t = time2(tmp, funcp, offset, &okay); 1915 #ifdef PCTS 1916 /* 1917 ** PCTS code courtesy Grant Sullivan. 1918 */ 1919 if (okay) 1920 return t; 1921 if (tmp->tm_isdst < 0) 1922 tmp->tm_isdst = 0; /* reset to std and try again */ 1923 #endif /* defined PCTS */ 1924 #ifndef PCTS 1925 if (okay || tmp->tm_isdst < 0) 1926 return t; 1927 #endif /* !defined PCTS */ 1928 /* 1929 ** We're supposed to assume that somebody took a time of one type 1930 ** and did some math on it that yielded a "struct tm" that's bad. 1931 ** We try to divine the type they started from and adjust to the 1932 ** type they need. 1933 */ 1934 sp = (const struct state *) ((funcp == localsub) ? lclptr : gmtptr); 1935 #ifdef ALL_STATE 1936 if (sp == NULL) 1937 return WRONG; 1938 #endif /* defined ALL_STATE */ 1939 for (i = 0; i < sp->typecnt; ++i) 1940 seen[i] = FALSE; 1941 nseen = 0; 1942 for (i = sp->timecnt - 1; i >= 0; --i) 1943 if (!seen[sp->types[i]]) { 1944 seen[sp->types[i]] = TRUE; 1945 types[nseen++] = sp->types[i]; 1946 } 1947 for (sameind = 0; sameind < nseen; ++sameind) { 1948 samei = types[sameind]; 1949 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) 1950 continue; 1951 for (otherind = 0; otherind < nseen; ++otherind) { 1952 otheri = types[otherind]; 1953 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) 1954 continue; 1955 tmp->tm_sec += sp->ttis[otheri].tt_gmtoff - 1956 sp->ttis[samei].tt_gmtoff; 1957 tmp->tm_isdst = !tmp->tm_isdst; 1958 t = time2(tmp, funcp, offset, &okay); 1959 if (okay) 1960 return t; 1961 tmp->tm_sec -= sp->ttis[otheri].tt_gmtoff - 1962 sp->ttis[samei].tt_gmtoff; 1963 tmp->tm_isdst = !tmp->tm_isdst; 1964 } 1965 } 1966 return WRONG; 1967 } 1968 1969 time_t 1970 mktime(struct tm * const tmp) 1971 { 1972 time_t mktime_return_value; 1973 _MUTEX_LOCK(&lcl_mutex); 1974 tzset(); 1975 mktime_return_value = time1(tmp, localsub, 0L); 1976 _MUTEX_UNLOCK(&lcl_mutex); 1977 return(mktime_return_value); 1978 } 1979 1980 #ifdef STD_INSPIRED 1981 1982 time_t 1983 timelocal(struct tm * const tmp) 1984 { 1985 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 1986 return mktime(tmp); 1987 } 1988 1989 time_t 1990 timegm(struct tm * const tmp) 1991 { 1992 tmp->tm_isdst = 0; 1993 return time1(tmp, gmtsub, 0L); 1994 } 1995 1996 time_t 1997 timeoff(struct tm * const tmp, const long offset) 1998 { 1999 tmp->tm_isdst = 0; 2000 return time1(tmp, gmtsub, offset); 2001 } 2002 2003 #endif /* defined STD_INSPIRED */ 2004 2005 #ifdef CMUCS 2006 2007 /* 2008 ** The following is supplied for compatibility with 2009 ** previous versions of the CMUCS runtime library. 2010 */ 2011 2012 long 2013 gtime(struct tm * const tmp) 2014 { 2015 const time_t t = mktime(tmp); 2016 2017 if (t == WRONG) 2018 return -1; 2019 return t; 2020 } 2021 2022 #endif /* defined CMUCS */ 2023 2024 /* 2025 ** XXX--is the below the right way to conditionalize?? 2026 */ 2027 2028 #ifdef STD_INSPIRED 2029 2030 /* 2031 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 2032 ** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which 2033 ** is not the case if we are accounting for leap seconds. 2034 ** So, we provide the following conversion routines for use 2035 ** when exchanging timestamps with POSIX conforming systems. 2036 */ 2037 2038 static long 2039 leapcorr(time_t *timep) 2040 { 2041 struct state * sp; 2042 struct lsinfo * lp; 2043 int i; 2044 2045 sp = lclptr; 2046 i = sp->leapcnt; 2047 while (--i >= 0) { 2048 lp = &sp->lsis[i]; 2049 if (*timep >= lp->ls_trans) 2050 return lp->ls_corr; 2051 } 2052 return 0; 2053 } 2054 2055 time_t 2056 time2posix(time_t t) 2057 { 2058 tzset(); 2059 return t - leapcorr(&t); 2060 } 2061 2062 time_t 2063 posix2time(time_t t) 2064 { 2065 time_t x; 2066 time_t y; 2067 2068 tzset(); 2069 /* 2070 ** For a positive leap second hit, the result 2071 ** is not unique. For a negative leap second 2072 ** hit, the corresponding time doesn't exist, 2073 ** so we return an adjacent second. 2074 */ 2075 x = t + leapcorr(&t); 2076 y = x - leapcorr(&x); 2077 if (y < t) { 2078 do { 2079 x++; 2080 y = x - leapcorr(&x); 2081 } while (y < t); 2082 if (t != y) 2083 return x - 1; 2084 } else if (y > t) { 2085 do { 2086 --x; 2087 y = x - leapcorr(&x); 2088 } while (y > t); 2089 if (t != y) 2090 return x + 1; 2091 } 2092 return x; 2093 } 2094 2095 #endif /* defined STD_INSPIRED */ 2096