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 ** Someone might make incorrect use of a time zone abbreviation: 50 ** 1. They might reference tzname[0] before calling tzset (explicitly 51 ** or implicitly). 52 ** 2. They might reference tzname[1] before calling tzset (explicitly 53 ** or implicitly). 54 ** 3. They might reference tzname[1] after setting to a time zone 55 ** in which Daylight Saving Time is never observed. 56 ** 4. They might reference tzname[0] after setting to a time zone 57 ** in which Standard Time is never observed. 58 ** 5. They might reference tm.TM_ZONE after calling offtime. 59 ** What's best to do in the above cases is open to debate; 60 ** for now, we just set things up so that in any of the five cases 61 ** WILDABBR is used. Another possibility: initialize tzname[0] to the 62 ** string "tzname[0] used before set", and similarly for the other cases. 63 ** And another: initialize tzname[0] to "ERA", with an explanation in the 64 ** manual page of what this "time zone abbreviation" means (doing this so 65 ** that tzname[0] has the "normal" length of three characters). 66 */ 67 #define WILDABBR " " 68 69 static char wildabbr[] = WILDABBR; 70 71 static const char gmt[] = "GMT"; 72 73 /* 74 ** The DST rules to use if TZ has no rules and we can't load TZDEFRULES. 75 ** We default to US rules as of 1999-08-17. 76 ** POSIX 1003.1 section 8.1.1 says that the default DST rules are 77 ** implementation dependent; for historical reasons, US rules are a 78 ** common default. 79 */ 80 #ifndef TZDEFRULESTRING 81 #define TZDEFRULESTRING ",M4.1.0,M10.5.0" 82 #endif /* !defined TZDEFDST */ 83 84 struct ttinfo { /* time type information */ 85 long tt_gmtoff; /* UTC offset in seconds */ 86 int tt_isdst; /* used to set tm_isdst */ 87 int tt_abbrind; /* abbreviation list index */ 88 int tt_ttisstd; /* TRUE if transition is std time */ 89 int tt_ttisgmt; /* TRUE if transition is UTC */ 90 }; 91 92 struct lsinfo { /* leap second information */ 93 time_t ls_trans; /* transition time */ 94 long ls_corr; /* correction to apply */ 95 }; 96 97 #define BIGGEST(a, b) (((a) > (b)) ? (a) : (b)) 98 99 #ifdef TZNAME_MAX 100 #define MY_TZNAME_MAX TZNAME_MAX 101 #endif /* defined TZNAME_MAX */ 102 #ifndef TZNAME_MAX 103 #define MY_TZNAME_MAX 255 104 #endif /* !defined TZNAME_MAX */ 105 106 struct state { 107 int leapcnt; 108 int timecnt; 109 int typecnt; 110 int charcnt; 111 int goback; 112 int goahead; 113 time_t ats[TZ_MAX_TIMES]; 114 unsigned char types[TZ_MAX_TIMES]; 115 struct ttinfo ttis[TZ_MAX_TYPES]; 116 char chars[BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt), 117 (2 * (MY_TZNAME_MAX + 1)))]; 118 struct lsinfo lsis[TZ_MAX_LEAPS]; 119 }; 120 121 struct rule { 122 int r_type; /* type of rule--see below */ 123 int r_day; /* day number of rule */ 124 int r_week; /* week number of rule */ 125 int r_mon; /* month number of rule */ 126 long r_time; /* transition time of rule */ 127 }; 128 129 #define JULIAN_DAY 0 /* Jn - Julian day */ 130 #define DAY_OF_YEAR 1 /* n - day of year */ 131 #define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */ 132 133 /* 134 ** Prototypes for static functions. 135 */ 136 137 static long detzcode(const char * codep); 138 static time_t detzcode64(const char * codep); 139 static int differ_by_repeat(time_t t1, time_t t0); 140 static const char * getzname(const char * strp); 141 static const char * getqzname(const char * strp, const int delim); 142 static const char * getnum(const char * strp, int * nump, int min, 143 int max); 144 static const char * getsecs(const char * strp, long * secsp); 145 static const char * getoffset(const char * strp, long * offsetp); 146 static const char * getrule(const char * strp, struct rule * rulep); 147 static void gmtload(struct state * sp); 148 static struct tm * gmtsub(const time_t * timep, long offset, 149 struct tm * tmp); 150 static struct tm * localsub(const time_t * timep, long offset, 151 struct tm * tmp); 152 static int increment_overflow(int * number, int delta); 153 static int leaps_thru_end_of(int y); 154 static int long_increment_overflow(long * number, int delta); 155 static int long_normalize_overflow(long * tensptr, 156 int * unitsptr, int base); 157 static int normalize_overflow(int * tensptr, int * unitsptr, 158 int base); 159 static void settzname(void); 160 static time_t time1(struct tm * tmp, 161 struct tm * (*funcp)(const time_t *, 162 long, struct tm *), 163 long offset); 164 static time_t time2(struct tm *tmp, 165 struct tm * (*funcp)(const time_t *, 166 long, struct tm*), 167 long offset, int * okayp); 168 static time_t time2sub(struct tm *tmp, 169 struct tm * (*funcp)(const time_t *, 170 long, struct tm*), 171 long offset, int * okayp, int do_norm_secs); 172 static struct tm * timesub(const time_t * timep, long offset, 173 const struct state * sp, struct tm * tmp); 174 static int tmcomp(const struct tm * atmp, 175 const struct tm * btmp); 176 static time_t transtime(time_t janfirst, int year, 177 const struct rule * rulep, long offset); 178 static int typesequiv(const struct state * sp, int a, int b); 179 static int tzload(const char * name, struct state * sp, 180 int doextend); 181 static int tzparse(const char * name, struct state * sp, 182 int lastditch); 183 184 static struct state lclmem; 185 static struct state gmtmem; 186 #define lclptr (&lclmem) 187 #define gmtptr (&gmtmem) 188 189 #ifndef TZ_STRLEN_MAX 190 #define TZ_STRLEN_MAX 255 191 #endif /* !defined TZ_STRLEN_MAX */ 192 193 static char lcl_TZname[TZ_STRLEN_MAX + 1]; 194 static int lcl_is_set; 195 static int gmt_is_set; 196 static pthread_mutex_t lcl_mutex = PTHREAD_MUTEX_INITIALIZER; 197 static pthread_mutex_t gmt_mutex = PTHREAD_MUTEX_INITIALIZER; 198 199 char * tzname[2] = { 200 wildabbr, 201 wildabbr 202 }; 203 204 /* 205 ** Section 4.12.3 of X3.159-1989 requires that 206 ** Except for the strftime function, these functions [asctime, 207 ** ctime, gmtime, localtime] return values in one of two static 208 ** objects: a broken-down time structure and an array of char. 209 ** Thanks to Paul Eggert for noting this. 210 */ 211 212 static struct tm tm; 213 214 static long 215 detzcode(const char * const codep) 216 { 217 long result; 218 int i; 219 220 result = (codep[0] & 0x80) ? ~0L : 0; 221 for (i = 0; i < 4; ++i) 222 result = (result << 8) | (codep[i] & 0xff); 223 return result; 224 } 225 226 static time_t 227 detzcode64(const char * const codep) 228 { 229 time_t result; 230 int i; 231 232 result = (codep[0] & 0x80) ? (~(int_fast64_t) 0) : 0; 233 for (i = 0; i < 8; ++i) 234 result = result * 256 + (codep[i] & 0xff); 235 return result; 236 } 237 238 static void 239 settzname(void) 240 { 241 struct state * const sp = lclptr; 242 int i; 243 244 tzname[0] = wildabbr; 245 tzname[1] = wildabbr; 246 247 for (i = 0; i < sp->typecnt; ++i) { 248 const struct ttinfo * const ttisp = &sp->ttis[i]; 249 250 tzname[ttisp->tt_isdst] = 251 &sp->chars[ttisp->tt_abbrind]; 252 } 253 /* 254 ** And to get the latest zone names into tzname. . . 255 */ 256 for (i = 0; i < sp->timecnt; ++i) { 257 const struct ttinfo * const ttisp = 258 &sp->ttis[ 259 sp->types[i]]; 260 261 tzname[ttisp->tt_isdst] = 262 &sp->chars[ttisp->tt_abbrind]; 263 } 264 /* 265 ** Finally, scrub the abbreviations. 266 ** First, replace bogus characters. 267 */ 268 for (i = 0; i < sp->charcnt; ++i) 269 if (strchr(TZ_ABBR_CHAR_SET, sp->chars[i]) == NULL) 270 sp->chars[i] = TZ_ABBR_ERR_CHAR; 271 /* 272 ** Second, truncate long abbreviations. 273 */ 274 for (i = 0; i < sp->typecnt; ++i) { 275 const struct ttinfo * const ttisp = &sp->ttis[i]; 276 char * cp = &sp->chars[ttisp->tt_abbrind]; 277 278 if (strlen(cp) > TZ_ABBR_MAX_LEN && 279 strcmp(cp, GRANDPARENTED) != 0) 280 *(cp + TZ_ABBR_MAX_LEN) = '\0'; 281 } 282 } 283 284 static int 285 differ_by_repeat(const time_t t1, const time_t t0) 286 { 287 if (TYPE_INTEGRAL(time_t) && 288 TYPE_BIT(time_t) - TYPE_SIGNED(time_t) < SECSPERREPEAT_BITS) 289 return 0; 290 return t1 - t0 == SECSPERREPEAT; 291 } 292 293 static int 294 tzload(const char *name, struct state * const sp, const int doextend) 295 { 296 const char * p; 297 int i; 298 int fid; 299 int stored; 300 int nread; 301 union { 302 struct tzhead tzhead; 303 char buf[2 * sizeof(struct tzhead) + 304 2 * sizeof *sp + 305 4 * TZ_MAX_TIMES]; 306 } u; 307 308 /* XXX The following is from OpenBSD, and I'm not sure it is correct */ 309 if (name != NULL && issetugid() != 0) 310 if ((name[0] == ':' && name[1] == '/') || 311 name[0] == '/' || strchr(name, '.')) 312 name = NULL; 313 if (name == NULL && (name = TZDEFAULT) == NULL) 314 return -1; 315 { 316 int doaccess; 317 struct stat stab; 318 /* 319 ** Section 4.9.1 of the C standard says that 320 ** "FILENAME_MAX expands to an integral constant expression 321 ** that is the size needed for an array of char large enough 322 ** to hold the longest file name string that the implementation 323 ** guarantees can be opened." 324 */ 325 char fullname[FILENAME_MAX + 1]; 326 327 if (name[0] == ':') 328 ++name; 329 doaccess = name[0] == '/'; 330 if (!doaccess) { 331 if ((p = TZDIR) == NULL) 332 return -1; 333 if ((strlen(p) + 1 + strlen(name) + 1) >= sizeof fullname) 334 return -1; 335 strcpy(fullname, p); 336 strcat(fullname, "/"); 337 strcat(fullname, name); 338 /* 339 ** Set doaccess if '.' (as in "../") shows up in name. 340 */ 341 if (strchr(name, '.') != NULL) 342 doaccess = TRUE; 343 name = fullname; 344 } 345 if (doaccess && access(name, R_OK) != 0) 346 return -1; 347 if ((fid = _open(name, O_RDONLY)) == -1) 348 return -1; 349 if ((_fstat(fid, &stab) < 0) || !S_ISREG(stab.st_mode)) { 350 _close(fid); 351 return -1; 352 } 353 } 354 nread = read(fid, u.buf, sizeof u.buf); 355 if (close(fid) < 0 || nread <= 0) 356 return -1; 357 for (stored = 4; stored <= 8; stored *= 2) { 358 int ttisstdcnt; 359 int ttisgmtcnt; 360 361 ttisstdcnt = (int) detzcode(u.tzhead.tzh_ttisstdcnt); 362 ttisgmtcnt = (int) detzcode(u.tzhead.tzh_ttisgmtcnt); 363 sp->leapcnt = (int) detzcode(u.tzhead.tzh_leapcnt); 364 sp->timecnt = (int) detzcode(u.tzhead.tzh_timecnt); 365 sp->typecnt = (int) detzcode(u.tzhead.tzh_typecnt); 366 sp->charcnt = (int) detzcode(u.tzhead.tzh_charcnt); 367 p = u.tzhead.tzh_charcnt + sizeof u.tzhead.tzh_charcnt; 368 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS || 369 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES || 370 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES || 371 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS || 372 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) || 373 (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0)) 374 return -1; 375 if (nread - (p - u.buf) < 376 sp->timecnt * stored + /* ats */ 377 sp->timecnt + /* types */ 378 sp->typecnt * 6 + /* ttinfos */ 379 sp->charcnt + /* chars */ 380 sp->leapcnt * (stored + 4) + /* lsinfos */ 381 ttisstdcnt + /* ttisstds */ 382 ttisgmtcnt) /* ttisgmts */ 383 return -1; 384 for (i = 0; i < sp->timecnt; ++i) { 385 sp->ats[i] = (stored == 4) ? 386 detzcode(p) : detzcode64(p); 387 p += stored; 388 } 389 for (i = 0; i < sp->timecnt; ++i) { 390 sp->types[i] = (unsigned char) *p++; 391 if (sp->types[i] >= sp->typecnt) 392 return -1; 393 } 394 for (i = 0; i < sp->typecnt; ++i) { 395 struct ttinfo * ttisp; 396 397 ttisp = &sp->ttis[i]; 398 ttisp->tt_gmtoff = detzcode(p); 399 p += 4; 400 ttisp->tt_isdst = (unsigned char) *p++; 401 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1) 402 return -1; 403 ttisp->tt_abbrind = (unsigned char) *p++; 404 if (ttisp->tt_abbrind < 0 || 405 ttisp->tt_abbrind > sp->charcnt) 406 return -1; 407 } 408 for (i = 0; i < sp->charcnt; ++i) 409 sp->chars[i] = *p++; 410 sp->chars[i] = '\0'; /* ensure '\0' at end */ 411 for (i = 0; i < sp->leapcnt; ++i) { 412 struct lsinfo * lsisp; 413 414 lsisp = &sp->lsis[i]; 415 lsisp->ls_trans = (stored == 4) ? 416 detzcode(p) : detzcode64(p); 417 p += stored; 418 lsisp->ls_corr = detzcode(p); 419 p += 4; 420 } 421 for (i = 0; i < sp->typecnt; ++i) { 422 struct ttinfo * ttisp; 423 424 ttisp = &sp->ttis[i]; 425 if (ttisstdcnt == 0) 426 ttisp->tt_ttisstd = FALSE; 427 else { 428 ttisp->tt_ttisstd = *p++; 429 if (ttisp->tt_ttisstd != TRUE && 430 ttisp->tt_ttisstd != FALSE) 431 return -1; 432 } 433 } 434 for (i = 0; i < sp->typecnt; ++i) { 435 struct ttinfo * ttisp; 436 437 ttisp = &sp->ttis[i]; 438 if (ttisgmtcnt == 0) 439 ttisp->tt_ttisgmt = FALSE; 440 else { 441 ttisp->tt_ttisgmt = *p++; 442 if (ttisp->tt_ttisgmt != TRUE && 443 ttisp->tt_ttisgmt != FALSE) 444 return -1; 445 } 446 } 447 /* 448 ** Out-of-sort ats should mean we're running on a 449 ** signed time_t system but using a data file with 450 ** unsigned values (or vice versa). 451 */ 452 for (i = 0; i < sp->timecnt - 2; ++i) 453 if (sp->ats[i] > sp->ats[i + 1]) { 454 ++i; 455 if (TYPE_SIGNED(time_t)) { 456 /* 457 ** Ignore the end (easy). 458 */ 459 sp->timecnt = i; 460 } else { 461 /* 462 ** Ignore the beginning (harder). 463 */ 464 int j; 465 466 for (j = 0; j + i < sp->timecnt; ++j) { 467 sp->ats[j] = sp->ats[j + i]; 468 sp->types[j] = sp->types[j + i]; 469 } 470 sp->timecnt = j; 471 } 472 break; 473 } 474 /* 475 ** If this is an old file, we're done. 476 */ 477 if (u.tzhead.tzh_version[0] == '\0') 478 break; 479 nread -= p - u.buf; 480 for (i = 0; i < nread; ++i) 481 u.buf[i] = p[i]; 482 /* 483 ** If this is a narrow integer time_t system, we're done. 484 */ 485 if (stored >= (int) sizeof(time_t) && TYPE_INTEGRAL(time_t)) 486 break; 487 } 488 if (doextend && nread > 2 && 489 u.buf[0] == '\n' && u.buf[nread - 1] == '\n' && 490 sp->typecnt + 2 <= TZ_MAX_TYPES) { 491 struct state ts; 492 int result; 493 494 u.buf[nread - 1] = '\0'; 495 result = tzparse(&u.buf[1], &ts, FALSE); 496 if (result == 0 && ts.typecnt == 2 && 497 sp->charcnt + ts.charcnt <= TZ_MAX_CHARS) { 498 for (i = 0; i < 2; ++i) 499 ts.ttis[i].tt_abbrind += 500 sp->charcnt; 501 for (i = 0; i < ts.charcnt; ++i) 502 sp->chars[sp->charcnt++] = 503 ts.chars[i]; 504 i = 0; 505 while (i < ts.timecnt && 506 ts.ats[i] <= 507 sp->ats[sp->timecnt - 1]) 508 ++i; 509 while (i < ts.timecnt && 510 sp->timecnt < TZ_MAX_TIMES) { 511 sp->ats[sp->timecnt] = 512 ts.ats[i]; 513 sp->types[sp->timecnt] = 514 sp->typecnt + 515 ts.types[i]; 516 ++sp->timecnt; 517 ++i; 518 } 519 sp->ttis[sp->typecnt++] = ts.ttis[0]; 520 sp->ttis[sp->typecnt++] = ts.ttis[1]; 521 } 522 } 523 sp->goback = sp->goahead = FALSE; 524 if (sp->timecnt > 1) { 525 for (i = 1; i < sp->timecnt; ++i) 526 if (typesequiv(sp, sp->types[i], sp->types[0]) && 527 differ_by_repeat(sp->ats[i], sp->ats[0])) { 528 sp->goback = TRUE; 529 break; 530 } 531 for (i = sp->timecnt - 2; i >= 0; --i) 532 if (typesequiv(sp, sp->types[sp->timecnt - 1], 533 sp->types[i]) && 534 differ_by_repeat(sp->ats[sp->timecnt - 1], 535 sp->ats[i])) { 536 sp->goahead = TRUE; 537 break; 538 } 539 } 540 return 0; 541 } 542 543 static int 544 typesequiv(const struct state * const sp, const int a, const int b) 545 { 546 int result; 547 548 if (sp == NULL || 549 a < 0 || a >= sp->typecnt || 550 b < 0 || b >= sp->typecnt) 551 result = FALSE; 552 else { 553 const struct ttinfo * ap = &sp->ttis[a]; 554 const struct ttinfo * bp = &sp->ttis[b]; 555 result = ap->tt_gmtoff == bp->tt_gmtoff && 556 ap->tt_isdst == bp->tt_isdst && 557 ap->tt_ttisstd == bp->tt_ttisstd && 558 ap->tt_ttisgmt == bp->tt_ttisgmt && 559 strcmp(&sp->chars[ap->tt_abbrind], 560 &sp->chars[bp->tt_abbrind]) == 0; 561 } 562 return result; 563 } 564 565 static const int mon_lengths[2][MONSPERYEAR] = { 566 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, 567 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } 568 }; 569 570 static const int year_lengths[2] = { 571 DAYSPERNYEAR, DAYSPERLYEAR 572 }; 573 574 /* 575 ** Given a pointer into a time zone string, scan until a character that is not 576 ** a valid character in a zone name is found. Return a pointer to that 577 ** character. 578 */ 579 580 static const char * 581 getzname(const char *strp) 582 { 583 char c; 584 585 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && 586 c != '+') 587 ++strp; 588 return strp; 589 } 590 591 /* 592 ** Given a pointer into an extended time zone string, scan until the ending 593 ** delimiter of the zone name is located. Return a pointer to the delimiter. 594 ** 595 ** As with getzname above, the legal character set is actually quite 596 ** restricted, with other characters producing undefined results. 597 ** We don't do any checking here; checking is done later in common-case code. 598 */ 599 600 static const char * 601 getqzname(const char *strp, const int delim) 602 { 603 int c; 604 605 while ((c = *strp) != '\0' && c != delim) 606 ++strp; 607 return strp; 608 } 609 610 /* 611 ** Given a pointer into a time zone string, extract a number from that string. 612 ** Check that the number is within a specified range; if it is not, return 613 ** NULL. 614 ** Otherwise, return a pointer to the first character not part of the number. 615 */ 616 617 static const char * 618 getnum(const char *strp, int * const nump, const int min, const int max) 619 { 620 char c; 621 int num; 622 623 if (strp == NULL || !is_digit(c = *strp)) 624 return NULL; 625 num = 0; 626 do { 627 num = num * 10 + (c - '0'); 628 if (num > max) 629 return NULL; /* illegal value */ 630 c = *++strp; 631 } while (is_digit(c)); 632 if (num < min) 633 return NULL; /* illegal value */ 634 *nump = num; 635 return strp; 636 } 637 638 /* 639 ** Given a pointer into a time zone string, extract a number of seconds, 640 ** in hh[:mm[:ss]] form, from the string. 641 ** If any error occurs, return NULL. 642 ** Otherwise, return a pointer to the first character not part of the number 643 ** of seconds. 644 */ 645 646 static const char * 647 getsecs(const char *strp, long * const secsp) 648 { 649 int num; 650 651 /* 652 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like 653 ** "M10.4.6/26", which does not conform to Posix, 654 ** but which specifies the equivalent of 655 ** ``02:00 on the first Sunday on or after 23 Oct''. 656 */ 657 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); 658 if (strp == NULL) 659 return NULL; 660 *secsp = num * (long) SECSPERHOUR; 661 if (*strp == ':') { 662 ++strp; 663 strp = getnum(strp, &num, 0, MINSPERHOUR - 1); 664 if (strp == NULL) 665 return NULL; 666 *secsp += num * SECSPERMIN; 667 if (*strp == ':') { 668 ++strp; 669 /* `SECSPERMIN' allows for leap seconds. */ 670 strp = getnum(strp, &num, 0, SECSPERMIN); 671 if (strp == NULL) 672 return NULL; 673 *secsp += num; 674 } 675 } 676 return strp; 677 } 678 679 /* 680 ** Given a pointer into a time zone string, extract an offset, in 681 ** [+-]hh[:mm[:ss]] form, from the string. 682 ** If any error occurs, return NULL. 683 ** Otherwise, return a pointer to the first character not part of the time. 684 */ 685 686 static const char * 687 getoffset(const char *strp, long * const offsetp) 688 { 689 int neg = 0; 690 691 if (*strp == '-') { 692 neg = 1; 693 ++strp; 694 } else if (*strp == '+') 695 ++strp; 696 strp = getsecs(strp, offsetp); 697 if (strp == NULL) 698 return NULL; /* illegal time */ 699 if (neg) 700 *offsetp = -*offsetp; 701 return strp; 702 } 703 704 /* 705 ** Given a pointer into a time zone string, extract a rule in the form 706 ** date[/time]. See POSIX section 8 for the format of "date" and "time". 707 ** If a valid rule is not found, return NULL. 708 ** Otherwise, return a pointer to the first character not part of the rule. 709 */ 710 711 static const char * 712 getrule(const char *strp, struct rule * const rulep) 713 { 714 if (*strp == 'J') { 715 /* 716 ** Julian day. 717 */ 718 rulep->r_type = JULIAN_DAY; 719 ++strp; 720 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); 721 } else if (*strp == 'M') { 722 /* 723 ** Month, week, day. 724 */ 725 rulep->r_type = MONTH_NTH_DAY_OF_WEEK; 726 ++strp; 727 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); 728 if (strp == NULL) 729 return NULL; 730 if (*strp++ != '.') 731 return NULL; 732 strp = getnum(strp, &rulep->r_week, 1, 5); 733 if (strp == NULL) 734 return NULL; 735 if (*strp++ != '.') 736 return NULL; 737 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); 738 } else if (is_digit(*strp)) { 739 /* 740 ** Day of year. 741 */ 742 rulep->r_type = DAY_OF_YEAR; 743 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); 744 } else return NULL; /* invalid format */ 745 if (strp == NULL) 746 return NULL; 747 if (*strp == '/') { 748 /* 749 ** Time specified. 750 */ 751 ++strp; 752 strp = getsecs(strp, &rulep->r_time); 753 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ 754 return strp; 755 } 756 757 /* 758 ** Given the Epoch-relative time of January 1, 00:00:00 UTC, in a year, the 759 ** year, a rule, and the offset from UTC at the time that rule takes effect, 760 ** calculate the Epoch-relative time that rule takes effect. 761 */ 762 763 static time_t 764 transtime(const time_t janfirst, const int year, 765 const struct rule * const rulep, const long offset) 766 { 767 int leapyear; 768 time_t value; 769 int i; 770 int d, m1, yy0, yy1, yy2, dow; 771 772 INITIALIZE(value); 773 leapyear = isleap(year); 774 switch (rulep->r_type) { 775 776 case JULIAN_DAY: 777 /* 778 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap 779 ** years. 780 ** In non-leap years, or if the day number is 59 or less, just 781 ** add SECSPERDAY times the day number-1 to the time of 782 ** January 1, midnight, to get the day. 783 */ 784 value = janfirst + (rulep->r_day - 1) * SECSPERDAY; 785 if (leapyear && rulep->r_day >= 60) 786 value += SECSPERDAY; 787 break; 788 789 case DAY_OF_YEAR: 790 /* 791 ** n - day of year. 792 ** Just add SECSPERDAY times the day number to the time of 793 ** January 1, midnight, to get the day. 794 */ 795 value = janfirst + rulep->r_day * SECSPERDAY; 796 break; 797 798 case MONTH_NTH_DAY_OF_WEEK: 799 /* 800 ** Mm.n.d - nth "dth day" of month m. 801 */ 802 value = janfirst; 803 for (i = 0; i < rulep->r_mon - 1; ++i) 804 value += mon_lengths[leapyear][i] * SECSPERDAY; 805 806 /* 807 ** Use Zeller's Congruence to get day-of-week of first day of 808 ** month. 809 */ 810 m1 = (rulep->r_mon + 9) % 12 + 1; 811 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; 812 yy1 = yy0 / 100; 813 yy2 = yy0 % 100; 814 dow = ((26 * m1 - 2) / 10 + 815 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; 816 if (dow < 0) 817 dow += DAYSPERWEEK; 818 819 /* 820 ** "dow" is the day-of-week of the first day of the month. Get 821 ** the day-of-month (zero-origin) of the first "dow" day of the 822 ** month. 823 */ 824 d = rulep->r_day - dow; 825 if (d < 0) 826 d += DAYSPERWEEK; 827 for (i = 1; i < rulep->r_week; ++i) { 828 if (d + DAYSPERWEEK >= 829 mon_lengths[leapyear][rulep->r_mon - 1]) 830 break; 831 d += DAYSPERWEEK; 832 } 833 834 /* 835 ** "d" is the day-of-month (zero-origin) of the day we want. 836 */ 837 value += d * SECSPERDAY; 838 break; 839 } 840 841 /* 842 ** "value" is the Epoch-relative time of 00:00:00 UTC on the day in 843 ** question. To get the Epoch-relative time of the specified local 844 ** time on that day, add the transition time and the current offset 845 ** from UTC. 846 */ 847 return value + rulep->r_time + offset; 848 } 849 850 /* 851 ** Given a POSIX section 8-style TZ string, fill in the rule tables as 852 ** appropriate. 853 */ 854 855 static int 856 tzparse(const char *name, struct state * const sp, const int lastditch) 857 { 858 const char * stdname; 859 const char * dstname; 860 size_t stdlen; 861 size_t dstlen; 862 long stdoffset; 863 long dstoffset; 864 time_t * atp; 865 unsigned char * typep; 866 char * cp; 867 int load_result; 868 869 INITIALIZE(dstname); 870 stdname = name; 871 if (lastditch) { 872 stdlen = strlen(name); /* length of standard zone name */ 873 name += stdlen; 874 if (stdlen >= sizeof sp->chars) 875 stdlen = (sizeof sp->chars) - 1; 876 stdoffset = 0; 877 } else { 878 if (*name == '<') { 879 name++; 880 stdname = name; 881 name = getqzname(name, '>'); 882 if (*name != '>') 883 return (-1); 884 stdlen = name - stdname; 885 name++; 886 } else { 887 name = getzname(name); 888 stdlen = name - stdname; 889 } 890 if (*name == '\0') 891 return -1; 892 name = getoffset(name, &stdoffset); 893 if (name == NULL) 894 return -1; 895 } 896 load_result = tzload(TZDEFRULES, sp, FALSE); 897 if (load_result != 0) 898 sp->leapcnt = 0; /* so, we're off a little */ 899 if (*name != '\0') { 900 if (*name == '<') { 901 dstname = ++name; 902 name = getqzname(name, '>'); 903 if (*name != '>') 904 return -1; 905 dstlen = name - dstname; 906 name++; 907 } else { 908 dstname = name; 909 name = getzname(name); 910 dstlen = name - dstname; /* length of DST zone name */ 911 } 912 if (*name != '\0' && *name != ',' && *name != ';') { 913 name = getoffset(name, &dstoffset); 914 if (name == NULL) 915 return -1; 916 } else dstoffset = stdoffset - SECSPERHOUR; 917 if (*name == '\0' && load_result != 0) 918 name = TZDEFRULESTRING; 919 if (*name == ',' || *name == ';') { 920 struct rule start; 921 struct rule end; 922 int year; 923 time_t janfirst; 924 time_t starttime; 925 time_t endtime; 926 927 ++name; 928 if ((name = getrule(name, &start)) == NULL) 929 return -1; 930 if (*name++ != ',') 931 return -1; 932 if ((name = getrule(name, &end)) == NULL) 933 return -1; 934 if (*name != '\0') 935 return -1; 936 sp->typecnt = 2; /* standard time and DST */ 937 /* 938 ** Two transitions per year, from EPOCH_YEAR forward. 939 */ 940 sp->ttis[0].tt_gmtoff = -dstoffset; 941 sp->ttis[0].tt_isdst = 1; 942 sp->ttis[0].tt_abbrind = stdlen + 1; 943 sp->ttis[1].tt_gmtoff = -stdoffset; 944 sp->ttis[1].tt_isdst = 0; 945 sp->ttis[1].tt_abbrind = 0; 946 atp = sp->ats; 947 typep = sp->types; 948 janfirst = 0; 949 sp->timecnt = 0; 950 for (year = EPOCH_YEAR; 951 sp->timecnt + 2 <= TZ_MAX_TIMES; 952 ++year) { 953 time_t newfirst; 954 955 starttime = transtime(janfirst, year, &start, 956 stdoffset); 957 endtime = transtime(janfirst, year, &end, 958 dstoffset); 959 if (starttime > endtime) { 960 *atp++ = endtime; 961 *typep++ = 1; /* DST ends */ 962 *atp++ = starttime; 963 *typep++ = 0; /* DST begins */ 964 } else { 965 *atp++ = starttime; 966 *typep++ = 0; /* DST begins */ 967 *atp++ = endtime; 968 *typep++ = 1; /* DST ends */ 969 } 970 sp->timecnt += 2; 971 newfirst = janfirst; 972 newfirst += year_lengths[isleap(year)] * 973 SECSPERDAY; 974 if (newfirst <= janfirst) 975 break; 976 janfirst = newfirst; 977 } 978 } else { 979 long theirstdoffset; 980 long theirdstoffset; 981 long theiroffset; 982 int isdst; 983 int i; 984 int j; 985 986 if (*name != '\0') 987 return -1; 988 /* 989 ** Initial values of theirstdoffset and theirdstoffset. 990 */ 991 theirstdoffset = 0; 992 for (i = 0; i < sp->timecnt; ++i) { 993 j = sp->types[i]; 994 if (!sp->ttis[j].tt_isdst) { 995 theirstdoffset = 996 -sp->ttis[j].tt_gmtoff; 997 break; 998 } 999 } 1000 theirdstoffset = 0; 1001 for (i = 0; i < sp->timecnt; ++i) { 1002 j = sp->types[i]; 1003 if (sp->ttis[j].tt_isdst) { 1004 theirdstoffset = 1005 -sp->ttis[j].tt_gmtoff; 1006 break; 1007 } 1008 } 1009 /* 1010 ** Initially we're assumed to be in standard time. 1011 */ 1012 isdst = FALSE; 1013 theiroffset = theirstdoffset; 1014 /* 1015 ** Now juggle transition times and types 1016 ** tracking offsets as you do. 1017 */ 1018 for (i = 0; i < sp->timecnt; ++i) { 1019 j = sp->types[i]; 1020 sp->types[i] = sp->ttis[j].tt_isdst; 1021 if (sp->ttis[j].tt_ttisgmt) { 1022 /* No adjustment to transition time */ 1023 } else { 1024 /* 1025 ** If summer time is in effect, and the 1026 ** transition time was not specified as 1027 ** standard time, add the summer time 1028 ** offset to the transition time; 1029 ** otherwise, add the standard time 1030 ** offset to the transition time. 1031 */ 1032 /* 1033 ** Transitions from DST to DDST 1034 ** will effectively disappear since 1035 ** POSIX provides for only one DST 1036 ** offset. 1037 */ 1038 if (isdst && !sp->ttis[j].tt_ttisstd) { 1039 sp->ats[i] += dstoffset - 1040 theirdstoffset; 1041 } else { 1042 sp->ats[i] += stdoffset - 1043 theirstdoffset; 1044 } 1045 } 1046 theiroffset = -sp->ttis[j].tt_gmtoff; 1047 if (sp->ttis[j].tt_isdst) 1048 theirdstoffset = theiroffset; 1049 else theirstdoffset = theiroffset; 1050 } 1051 /* 1052 ** Finally, fill in ttis. 1053 ** ttisstd and ttisgmt need not be handled. 1054 */ 1055 sp->ttis[0].tt_gmtoff = -stdoffset; 1056 sp->ttis[0].tt_isdst = FALSE; 1057 sp->ttis[0].tt_abbrind = 0; 1058 sp->ttis[1].tt_gmtoff = -dstoffset; 1059 sp->ttis[1].tt_isdst = TRUE; 1060 sp->ttis[1].tt_abbrind = stdlen + 1; 1061 sp->typecnt = 2; 1062 } 1063 } else { 1064 dstlen = 0; 1065 sp->typecnt = 1; /* only standard time */ 1066 sp->timecnt = 0; 1067 sp->ttis[0].tt_gmtoff = -stdoffset; 1068 sp->ttis[0].tt_isdst = 0; 1069 sp->ttis[0].tt_abbrind = 0; 1070 } 1071 sp->charcnt = stdlen + 1; 1072 if (dstlen != 0) 1073 sp->charcnt += dstlen + 1; 1074 if ((size_t) sp->charcnt > sizeof sp->chars) 1075 return -1; 1076 cp = sp->chars; 1077 strncpy(cp, stdname, stdlen); 1078 cp += stdlen; 1079 *cp++ = '\0'; 1080 if (dstlen != 0) { 1081 strncpy(cp, dstname, dstlen); 1082 *(cp + dstlen) = '\0'; 1083 } 1084 return 0; 1085 } 1086 1087 static void 1088 gmtload(struct state * const sp) 1089 { 1090 if (tzload(gmt, sp, TRUE) != 0) 1091 tzparse(gmt, sp, TRUE); 1092 } 1093 1094 static void 1095 tzsetwall_basic(void) 1096 { 1097 if (lcl_is_set < 0) 1098 return; 1099 lcl_is_set = -1; 1100 1101 if (tzload((char *) NULL, lclptr, TRUE) != 0) 1102 gmtload(lclptr); 1103 settzname(); 1104 } 1105 1106 void 1107 tzsetwall(void) 1108 { 1109 _MUTEX_LOCK(&lcl_mutex); 1110 tzsetwall_basic(); 1111 _MUTEX_UNLOCK(&lcl_mutex); 1112 } 1113 1114 static void 1115 tzset_basic(void) 1116 { 1117 const char * name; 1118 1119 name = getenv("TZ"); 1120 if (name == NULL) { 1121 tzsetwall(); 1122 return; 1123 } 1124 1125 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) 1126 return; 1127 lcl_is_set = strlen(name) < sizeof lcl_TZname; 1128 if (lcl_is_set) 1129 strcpy(lcl_TZname, name); 1130 1131 if (*name == '\0') { 1132 /* 1133 ** User wants it fast rather than right. 1134 */ 1135 lclptr->leapcnt = 0; /* so, we're off a little */ 1136 lclptr->timecnt = 0; 1137 lclptr->typecnt = 0; 1138 lclptr->ttis[0].tt_isdst = 0; 1139 lclptr->ttis[0].tt_gmtoff = 0; 1140 lclptr->ttis[0].tt_abbrind = 0; 1141 strcpy(lclptr->chars, gmt); 1142 } else if (tzload(name, lclptr, TRUE) != 0) 1143 if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0) 1144 gmtload(lclptr); 1145 settzname(); 1146 } 1147 1148 void 1149 tzset(void) 1150 { 1151 _MUTEX_LOCK(&lcl_mutex); 1152 tzset_basic(); 1153 _MUTEX_UNLOCK(&lcl_mutex); 1154 } 1155 1156 /* 1157 ** The easy way to behave "as if no library function calls" localtime 1158 ** is to not call it--so we drop its guts into "localsub", which can be 1159 ** freely called. (And no, the PANS doesn't require the above behavior-- 1160 ** but it *is* desirable.) 1161 ** 1162 ** The unused offset argument is for the benefit of mktime variants. 1163 */ 1164 1165 /*ARGSUSED*/ 1166 static struct tm * 1167 localsub(const time_t * const timep, const long offset __unused, 1168 struct tm * const tmp) 1169 { 1170 struct state * sp; 1171 const struct ttinfo * ttisp; 1172 int i; 1173 struct tm * result; 1174 const time_t t = *timep; 1175 1176 sp = lclptr; 1177 1178 if ((sp->goback && t < sp->ats[0]) || 1179 (sp->goahead && t > sp->ats[sp->timecnt - 1])) { 1180 time_t newt = t; 1181 time_t seconds; 1182 time_t tcycles; 1183 int_fast64_t icycles; 1184 1185 if (t < sp->ats[0]) 1186 seconds = sp->ats[0] - t; 1187 else seconds = t - sp->ats[sp->timecnt - 1]; 1188 --seconds; 1189 tcycles = seconds / YEARSPERREPEAT / AVGSECSPERYEAR; 1190 ++tcycles; 1191 icycles = tcycles; 1192 if (tcycles - icycles >= 1 || icycles - tcycles >= 1) 1193 return NULL; 1194 seconds = icycles; 1195 seconds *= YEARSPERREPEAT; 1196 seconds *= AVGSECSPERYEAR; 1197 if (t < sp->ats[0]) 1198 newt += seconds; 1199 else newt -= seconds; 1200 if (newt < sp->ats[0] || 1201 newt > sp->ats[sp->timecnt - 1]) 1202 return NULL; /* "cannot happen" */ 1203 result = localsub(&newt, offset, tmp); 1204 if (result == tmp) { 1205 time_t newy; 1206 1207 newy = tmp->tm_year; 1208 if (t < sp->ats[0]) 1209 newy -= icycles * YEARSPERREPEAT; 1210 else newy += icycles * YEARSPERREPEAT; 1211 tmp->tm_year = newy; 1212 if (tmp->tm_year != newy) 1213 return NULL; 1214 } 1215 return result; 1216 } 1217 if (sp->timecnt == 0 || t < sp->ats[0]) { 1218 i = 0; 1219 while (sp->ttis[i].tt_isdst) 1220 if (++i >= sp->typecnt) { 1221 i = 0; 1222 break; 1223 } 1224 } else { 1225 int lo = 1; 1226 int hi = sp->timecnt; 1227 1228 while (lo < hi) { 1229 int mid = (lo + hi) >> 1; 1230 1231 if (t < sp->ats[mid]) 1232 hi = mid; 1233 else lo = mid + 1; 1234 } 1235 i = (int) sp->types[lo - 1]; 1236 } 1237 ttisp = &sp->ttis[i]; 1238 /* 1239 ** To get (wrong) behavior that's compatible with System V Release 2.0 1240 ** you'd replace the statement below with 1241 ** t += ttisp->tt_gmtoff; 1242 ** timesub(&t, 0L, sp, tmp); 1243 */ 1244 result = timesub(&t, ttisp->tt_gmtoff, sp, tmp); 1245 tmp->tm_isdst = ttisp->tt_isdst; 1246 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind]; 1247 #ifdef TM_ZONE 1248 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind]; 1249 #endif /* defined TM_ZONE */ 1250 return result; 1251 } 1252 1253 struct tm * 1254 localtime_r(const time_t * const timep, struct tm *p_tm) 1255 { 1256 _MUTEX_LOCK(&lcl_mutex); 1257 tzset(); 1258 localsub(timep, 0L, p_tm); 1259 _MUTEX_UNLOCK(&lcl_mutex); 1260 return(p_tm); 1261 } 1262 1263 struct tm * 1264 localtime(const time_t * const timep) 1265 { 1266 static pthread_mutex_t localtime_mutex = PTHREAD_MUTEX_INITIALIZER; 1267 static pthread_key_t localtime_key = -1; 1268 struct tm *p_tm; 1269 1270 if (__isthreaded != 0) { 1271 _pthread_mutex_lock(&localtime_mutex); 1272 if (localtime_key < 0) { 1273 if (_pthread_key_create(&localtime_key, free) < 0) { 1274 _pthread_mutex_unlock(&localtime_mutex); 1275 return(NULL); 1276 } 1277 } 1278 _pthread_mutex_unlock(&localtime_mutex); 1279 p_tm = _pthread_getspecific(localtime_key); 1280 if (p_tm == NULL) { 1281 if ((p_tm = (struct tm *)malloc(sizeof(struct tm))) 1282 == NULL) 1283 return(NULL); 1284 _pthread_setspecific(localtime_key, p_tm); 1285 } 1286 _pthread_mutex_lock(&lcl_mutex); 1287 tzset(); 1288 localsub(timep, 0L, p_tm); 1289 _pthread_mutex_unlock(&lcl_mutex); 1290 return(p_tm); 1291 } else { 1292 tzset(); 1293 localsub(timep, 0L, &tm); 1294 return(&tm); 1295 } 1296 } 1297 1298 /* 1299 ** gmtsub is to gmtime as localsub is to localtime. 1300 */ 1301 1302 static struct tm * 1303 gmtsub(const time_t * const timep, const long offset, struct tm * const tmp) 1304 { 1305 struct tm * result; 1306 1307 _MUTEX_LOCK(&gmt_mutex); 1308 if (!gmt_is_set) { 1309 gmt_is_set = TRUE; 1310 gmtload(gmtptr); 1311 } 1312 _MUTEX_UNLOCK(&gmt_mutex); 1313 result = timesub(timep, offset, gmtptr, tmp); 1314 #ifdef TM_ZONE 1315 /* 1316 ** Could get fancy here and deliver something such as 1317 ** "UTC+xxxx" or "UTC-xxxx" if offset is non-zero, 1318 ** but this is no time for a treasure hunt. 1319 */ 1320 if (offset != 0) 1321 tmp->TM_ZONE = wildabbr; 1322 else 1323 tmp->TM_ZONE = gmtptr->chars; 1324 #endif /* defined TM_ZONE */ 1325 return result; 1326 } 1327 1328 struct tm * 1329 gmtime(const time_t * const timep) 1330 { 1331 static pthread_mutex_t gmtime_mutex = PTHREAD_MUTEX_INITIALIZER; 1332 static pthread_key_t gmtime_key = -1; 1333 struct tm *p_tm; 1334 1335 if (__isthreaded != 0) { 1336 _pthread_mutex_lock(&gmtime_mutex); 1337 if (gmtime_key < 0) { 1338 if (_pthread_key_create(&gmtime_key, free) < 0) { 1339 _pthread_mutex_unlock(&gmtime_mutex); 1340 return(NULL); 1341 } 1342 } 1343 _pthread_mutex_unlock(&gmtime_mutex); 1344 /* 1345 * Changed to follow POSIX.1 threads standard, which 1346 * is what BSD currently has. 1347 */ 1348 if ((p_tm = _pthread_getspecific(gmtime_key)) == NULL) { 1349 if ((p_tm = (struct tm *)malloc(sizeof(struct tm))) 1350 == NULL) { 1351 return(NULL); 1352 } 1353 _pthread_setspecific(gmtime_key, p_tm); 1354 } 1355 return gmtsub(timep, 0L, p_tm); 1356 } else { 1357 return gmtsub(timep, 0L, &tm); 1358 } 1359 } 1360 1361 struct tm * 1362 gmtime_r(const time_t * timep, struct tm * tmp) 1363 { 1364 return gmtsub(timep, 0L, tmp); 1365 } 1366 1367 struct tm * 1368 offtime(const time_t * const timep, const long offset) 1369 { 1370 return gmtsub(timep, offset, &tm); 1371 } 1372 1373 /* 1374 ** Return the number of leap years through the end of the given year 1375 ** where, to make the math easy, the answer for year zero is defined as zero. 1376 */ 1377 1378 static int 1379 leaps_thru_end_of(const int y) 1380 { 1381 return (y >= 0) ? (y / 4 - y / 100 + y / 400) : 1382 -(leaps_thru_end_of(-(y + 1)) + 1); 1383 } 1384 1385 static struct tm * 1386 timesub(const time_t * const timep, const long offset, 1387 const struct state * const sp, struct tm * const tmp) 1388 { 1389 const struct lsinfo * lp; 1390 time_t tdays; 1391 int idays; /* unsigned would be so 2003 */ 1392 long rem; 1393 int y; 1394 int yleap; 1395 const int * ip; 1396 long corr; 1397 int hit; 1398 int i; 1399 1400 corr = 0; 1401 hit = 0; 1402 i = sp->leapcnt; 1403 1404 while (--i >= 0) { 1405 lp = &sp->lsis[i]; 1406 if (*timep >= lp->ls_trans) { 1407 if (*timep == lp->ls_trans) { 1408 hit = ((i == 0 && lp->ls_corr > 0) || 1409 lp->ls_corr > sp->lsis[i - 1].ls_corr); 1410 if (hit) 1411 while (i > 0 && 1412 sp->lsis[i].ls_trans == 1413 sp->lsis[i - 1].ls_trans + 1 && 1414 sp->lsis[i].ls_corr == 1415 sp->lsis[i - 1].ls_corr + 1) { 1416 ++hit; 1417 --i; 1418 } 1419 } 1420 corr = lp->ls_corr; 1421 break; 1422 } 1423 } 1424 y = EPOCH_YEAR; 1425 tdays = *timep / SECSPERDAY; 1426 rem = *timep - tdays * SECSPERDAY; 1427 while (tdays < 0 || tdays >= year_lengths[isleap(y)]) { 1428 int newy; 1429 time_t tdelta; 1430 int idelta; 1431 int leapdays; 1432 1433 tdelta = tdays / DAYSPERLYEAR; 1434 idelta = tdelta; 1435 if (tdelta - idelta >= 1 || idelta - tdelta >= 1) 1436 return NULL; 1437 if (idelta == 0) 1438 idelta = (tdays < 0) ? -1 : 1; 1439 newy = y; 1440 if (increment_overflow(&newy, idelta)) 1441 return NULL; 1442 leapdays = leaps_thru_end_of(newy - 1) - 1443 leaps_thru_end_of(y - 1); 1444 tdays -= ((time_t) newy - y) * DAYSPERNYEAR; 1445 tdays -= leapdays; 1446 y = newy; 1447 } 1448 { 1449 long seconds; 1450 1451 seconds = tdays * SECSPERDAY + 0.5; 1452 tdays = seconds / SECSPERDAY; 1453 rem += seconds - tdays * SECSPERDAY; 1454 } 1455 /* 1456 ** Given the range, we can now fearlessly cast... 1457 */ 1458 idays = tdays; 1459 rem += offset - corr; 1460 while (rem < 0) { 1461 rem += SECSPERDAY; 1462 --idays; 1463 } 1464 while (rem >= SECSPERDAY) { 1465 rem -= SECSPERDAY; 1466 ++idays; 1467 } 1468 while (idays < 0) { 1469 if (increment_overflow(&y, -1)) 1470 return NULL; 1471 idays += year_lengths[isleap(y)]; 1472 } 1473 while (idays >= year_lengths[isleap(y)]) { 1474 idays -= year_lengths[isleap(y)]; 1475 if (increment_overflow(&y, 1)) 1476 return NULL; 1477 } 1478 tmp->tm_year = y; 1479 if (increment_overflow(&tmp->tm_year, -TM_YEAR_BASE)) 1480 return NULL; 1481 tmp->tm_yday = idays; 1482 /* 1483 ** The "extra" mods below avoid overflow problems. 1484 */ 1485 tmp->tm_wday = EPOCH_WDAY + 1486 ((y - EPOCH_YEAR) % DAYSPERWEEK) * 1487 (DAYSPERNYEAR % DAYSPERWEEK) + 1488 leaps_thru_end_of(y - 1) - 1489 leaps_thru_end_of(EPOCH_YEAR - 1) + 1490 idays; 1491 tmp->tm_wday %= DAYSPERWEEK; 1492 if (tmp->tm_wday < 0) 1493 tmp->tm_wday += DAYSPERWEEK; 1494 tmp->tm_hour = (int) (rem / SECSPERHOUR); 1495 rem %= SECSPERHOUR; 1496 tmp->tm_min = (int) (rem / SECSPERMIN); 1497 /* 1498 ** A positive leap second requires a special 1499 ** representation. This uses "... ??:59:60" et seq. 1500 */ 1501 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit; 1502 ip = mon_lengths[isleap(y)]; 1503 for (tmp->tm_mon = 0; idays >= ip[tmp->tm_mon]; ++(tmp->tm_mon)) 1504 idays -= ip[tmp->tm_mon]; 1505 tmp->tm_mday = (int) (idays + 1); 1506 tmp->tm_isdst = 0; 1507 #ifdef TM_GMTOFF 1508 tmp->TM_GMTOFF = offset; 1509 #endif /* defined TM_GMTOFF */ 1510 return tmp; 1511 } 1512 1513 char * 1514 ctime(const time_t * const timep) 1515 { 1516 /* 1517 ** Section 4.12.3.2 of X3.159-1989 requires that 1518 ** The ctime function converts the calendar time pointed to by timer 1519 ** to local time in the form of a string. It is equivalent to 1520 ** asctime(localtime(timer)) 1521 */ 1522 return asctime(localtime(timep)); 1523 } 1524 1525 char * 1526 ctime_r(const time_t * const timep, char *buf) 1527 { 1528 struct tm mytm; 1529 return asctime_r(localtime_r(timep, &mytm), buf); 1530 } 1531 1532 /* 1533 ** Adapted from code provided by Robert Elz, who writes: 1534 ** The "best" way to do mktime I think is based on an idea of Bob 1535 ** Kridle's (so its said...) from a long time ago. 1536 ** It does a binary search of the time_t space. Since time_t's are 1537 ** just 32 bits, its a max of 32 iterations (even at 64 bits it 1538 ** would still be very reasonable). 1539 */ 1540 1541 #ifndef WRONG 1542 #define WRONG (-1) 1543 #endif /* !defined WRONG */ 1544 1545 /* 1546 ** Simplified normalize logic courtesy Paul Eggert. 1547 */ 1548 1549 static int 1550 increment_overflow(int *number, int delta) 1551 { 1552 int number0; 1553 1554 number0 = *number; 1555 *number += delta; 1556 return (*number < number0) != (delta < 0); 1557 } 1558 1559 static int 1560 long_increment_overflow(long *number, int delta) 1561 { 1562 long number0; 1563 1564 number0 = *number; 1565 *number += delta; 1566 return (*number < number0) != (delta < 0); 1567 } 1568 1569 static int 1570 normalize_overflow(int * const tensptr, int * const unitsptr, const int base) 1571 { 1572 int tensdelta; 1573 1574 tensdelta = (*unitsptr >= 0) ? 1575 (*unitsptr / base) : 1576 (-1 - (-1 - *unitsptr) / base); 1577 *unitsptr -= tensdelta * base; 1578 return increment_overflow(tensptr, tensdelta); 1579 } 1580 1581 static int 1582 long_normalize_overflow(long * const tensptr, int * const unitsptr, 1583 const int base) 1584 { 1585 int tensdelta; 1586 1587 tensdelta = (*unitsptr >= 0) ? 1588 (*unitsptr / base) : 1589 (-1 - (-1 - *unitsptr) / base); 1590 *unitsptr -= tensdelta * base; 1591 return long_increment_overflow(tensptr, tensdelta); 1592 } 1593 1594 static int 1595 tmcomp(const struct tm * const atmp, const struct tm * const btmp) 1596 { 1597 int result; 1598 1599 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 && 1600 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 && 1601 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && 1602 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && 1603 (result = (atmp->tm_min - btmp->tm_min)) == 0) 1604 result = atmp->tm_sec - btmp->tm_sec; 1605 return result; 1606 } 1607 1608 static time_t 1609 time2sub(struct tm * const tmp, 1610 struct tm * (* const funcp)(const time_t *, long, struct tm *), 1611 const long offset, int * const okayp, const int do_norm_secs) 1612 { 1613 const struct state * sp; 1614 int dir; 1615 int i, j; 1616 int saved_seconds; 1617 long li; 1618 time_t lo; 1619 time_t hi; 1620 long y; 1621 time_t newt; 1622 time_t t; 1623 struct tm yourtm, mytm; 1624 1625 *okayp = FALSE; 1626 yourtm = *tmp; 1627 if (do_norm_secs) { 1628 if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec, 1629 SECSPERMIN)) 1630 return WRONG; 1631 } 1632 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) 1633 return WRONG; 1634 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) 1635 return WRONG; 1636 y = yourtm.tm_year; 1637 if (long_normalize_overflow(&y, &yourtm.tm_mon, MONSPERYEAR)) 1638 return WRONG; 1639 /* 1640 ** Turn y into an actual year number for now. 1641 ** It is converted back to an offset from TM_YEAR_BASE later. 1642 */ 1643 if (long_increment_overflow(&y, TM_YEAR_BASE)) 1644 return WRONG; 1645 while (yourtm.tm_mday <= 0) { 1646 if (long_increment_overflow(&y, -1)) 1647 return WRONG; 1648 li = y + (1 < yourtm.tm_mon); 1649 yourtm.tm_mday += year_lengths[isleap(li)]; 1650 } 1651 while (yourtm.tm_mday > DAYSPERLYEAR) { 1652 li = y + (1 < yourtm.tm_mon); 1653 yourtm.tm_mday -= year_lengths[isleap(li)]; 1654 if (long_increment_overflow(&y, 1)) 1655 return WRONG; 1656 } 1657 for ( ; ; ) { 1658 i = mon_lengths[isleap(y)][yourtm.tm_mon]; 1659 if (yourtm.tm_mday <= i) 1660 break; 1661 yourtm.tm_mday -= i; 1662 if (++yourtm.tm_mon >= MONSPERYEAR) { 1663 yourtm.tm_mon = 0; 1664 if (long_increment_overflow(&y, 1)) 1665 return WRONG; 1666 } 1667 } 1668 if (long_increment_overflow(&y, -TM_YEAR_BASE)) 1669 return WRONG; 1670 yourtm.tm_year = y; 1671 if (yourtm.tm_year != y) 1672 return WRONG; 1673 if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN) 1674 saved_seconds = 0; 1675 else if (y + TM_YEAR_BASE < EPOCH_YEAR) { 1676 /* 1677 ** We can't set tm_sec to 0, because that might push the 1678 ** time below the minimum representable time. 1679 ** Set tm_sec to 59 instead. 1680 ** This assumes that the minimum representable time is 1681 ** not in the same minute that a leap second was deleted from, 1682 ** which is a safer assumption than using 58 would be. 1683 */ 1684 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) 1685 return WRONG; 1686 saved_seconds = yourtm.tm_sec; 1687 yourtm.tm_sec = SECSPERMIN - 1; 1688 } else { 1689 saved_seconds = yourtm.tm_sec; 1690 yourtm.tm_sec = 0; 1691 } 1692 /* 1693 ** Do a binary search (this works whatever time_t's type is). 1694 */ 1695 if (!TYPE_SIGNED(time_t)) { 1696 lo = 0; 1697 hi = lo - 1; 1698 } else if (!TYPE_INTEGRAL(time_t)) { 1699 if (sizeof(time_t) > sizeof(float)) 1700 hi = (time_t) DBL_MAX; 1701 else hi = (time_t) FLT_MAX; 1702 lo = -hi; 1703 } else { 1704 lo = 1; 1705 for (i = 0; i < (int) TYPE_BIT(time_t) - 1; ++i) 1706 lo *= 2; 1707 hi = -(lo + 1); 1708 } 1709 for ( ; ; ) { 1710 t = lo / 2 + hi / 2; 1711 if (t < lo) 1712 t = lo; 1713 else if (t > hi) 1714 t = hi; 1715 if ((*funcp)(&t, offset, &mytm) == NULL) { 1716 /* 1717 ** Assume that t is too extreme to be represented in 1718 ** a struct tm; arrange things so that it is less 1719 ** extreme on the next pass. 1720 */ 1721 dir = (t > 0) ? 1 : -1; 1722 } else dir = tmcomp(&mytm, &yourtm); 1723 if (dir != 0) { 1724 if (t == lo) { 1725 ++t; 1726 if (t <= lo) 1727 return WRONG; 1728 ++lo; 1729 } else if (t == hi) { 1730 --t; 1731 if (t >= hi) 1732 return WRONG; 1733 --hi; 1734 } 1735 if (lo > hi) 1736 return WRONG; 1737 if (dir > 0) 1738 hi = t; 1739 else lo = t; 1740 continue; 1741 } 1742 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) 1743 break; 1744 /* 1745 ** Right time, wrong type. 1746 ** Hunt for right time, right type. 1747 ** It's okay to guess wrong since the guess 1748 ** gets checked. 1749 */ 1750 sp = (const struct state *) 1751 ((funcp == localsub) ? lclptr : gmtptr); 1752 1753 for (i = sp->typecnt - 1; i >= 0; --i) { 1754 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) 1755 continue; 1756 for (j = sp->typecnt - 1; j >= 0; --j) { 1757 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) 1758 continue; 1759 newt = t + sp->ttis[j].tt_gmtoff - 1760 sp->ttis[i].tt_gmtoff; 1761 if ((*funcp)(&newt, offset, &mytm) == NULL) 1762 continue; 1763 if (tmcomp(&mytm, &yourtm) != 0) 1764 continue; 1765 if (mytm.tm_isdst != yourtm.tm_isdst) 1766 continue; 1767 /* 1768 ** We have a match. 1769 */ 1770 t = newt; 1771 goto label; 1772 } 1773 } 1774 return WRONG; 1775 } 1776 label: 1777 newt = t + saved_seconds; 1778 if ((newt < t) != (saved_seconds < 0)) 1779 return WRONG; 1780 t = newt; 1781 if ((*funcp)(&t, offset, tmp)) 1782 *okayp = TRUE; 1783 return t; 1784 } 1785 1786 static time_t 1787 time2(struct tm * const tmp, 1788 struct tm * (* const funcp)(const time_t *, long, struct tm *), 1789 const long offset, int * const okayp) 1790 { 1791 time_t t; 1792 1793 /* 1794 ** First try without normalization of seconds 1795 ** (in case tm_sec contains a value associated with a leap second). 1796 ** If that fails, try with normalization of seconds. 1797 */ 1798 t = time2sub(tmp, funcp, offset, okayp, FALSE); 1799 return *okayp ? t : time2sub(tmp, funcp, offset, okayp, TRUE); 1800 } 1801 1802 static time_t 1803 time1(struct tm * const tmp, 1804 struct tm * (* const funcp)(const time_t *, long, struct tm *), 1805 const long offset) 1806 { 1807 time_t t; 1808 const struct state * sp; 1809 int samei, otheri; 1810 int sameind, otherind; 1811 int i; 1812 int nseen; 1813 int seen[TZ_MAX_TYPES]; 1814 int types[TZ_MAX_TYPES]; 1815 int okay; 1816 1817 if (tmp->tm_isdst > 1) 1818 tmp->tm_isdst = 1; 1819 t = time2(tmp, funcp, offset, &okay); 1820 1821 /* 1822 ** PCTS code courtesy Grant Sullivan. 1823 */ 1824 if (okay) 1825 return t; 1826 if (tmp->tm_isdst < 0) 1827 tmp->tm_isdst = 0; /* reset to std and try again */ 1828 1829 /* 1830 ** We're supposed to assume that somebody took a time of one type 1831 ** and did some math on it that yielded a "struct tm" that's bad. 1832 ** We try to divine the type they started from and adjust to the 1833 ** type they need. 1834 */ 1835 sp = (const struct state *) ((funcp == localsub) ? lclptr : gmtptr); 1836 1837 for (i = 0; i < sp->typecnt; ++i) 1838 seen[i] = FALSE; 1839 nseen = 0; 1840 for (i = sp->timecnt - 1; i >= 0; --i) 1841 if (!seen[sp->types[i]]) { 1842 seen[sp->types[i]] = TRUE; 1843 types[nseen++] = sp->types[i]; 1844 } 1845 for (sameind = 0; sameind < nseen; ++sameind) { 1846 samei = types[sameind]; 1847 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) 1848 continue; 1849 for (otherind = 0; otherind < nseen; ++otherind) { 1850 otheri = types[otherind]; 1851 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) 1852 continue; 1853 tmp->tm_sec += sp->ttis[otheri].tt_gmtoff - 1854 sp->ttis[samei].tt_gmtoff; 1855 tmp->tm_isdst = !tmp->tm_isdst; 1856 t = time2(tmp, funcp, offset, &okay); 1857 if (okay) 1858 return t; 1859 tmp->tm_sec -= sp->ttis[otheri].tt_gmtoff - 1860 sp->ttis[samei].tt_gmtoff; 1861 tmp->tm_isdst = !tmp->tm_isdst; 1862 } 1863 } 1864 return WRONG; 1865 } 1866 1867 time_t 1868 mktime(struct tm * const tmp) 1869 { 1870 time_t mktime_return_value; 1871 _MUTEX_LOCK(&lcl_mutex); 1872 tzset(); 1873 mktime_return_value = time1(tmp, localsub, 0L); 1874 _MUTEX_UNLOCK(&lcl_mutex); 1875 return(mktime_return_value); 1876 } 1877 1878 time_t 1879 timelocal(struct tm * const tmp) 1880 { 1881 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 1882 return mktime(tmp); 1883 } 1884 1885 time_t 1886 timegm(struct tm * const tmp) 1887 { 1888 tmp->tm_isdst = 0; 1889 return time1(tmp, gmtsub, 0L); 1890 } 1891 1892 time_t 1893 timeoff(struct tm * const tmp, const long offset) 1894 { 1895 tmp->tm_isdst = 0; 1896 return time1(tmp, gmtsub, offset); 1897 } 1898 1899 #ifdef CMUCS 1900 1901 /* 1902 ** The following is supplied for compatibility with 1903 ** previous versions of the CMUCS runtime library. 1904 */ 1905 1906 long 1907 gtime(struct tm * const tmp) 1908 { 1909 const time_t t = mktime(tmp); 1910 1911 if (t == WRONG) 1912 return -1; 1913 return t; 1914 } 1915 1916 #endif /* defined CMUCS */ 1917 1918 /* 1919 ** XXX--is the below the right way to conditionalize?? 1920 */ 1921 1922 /* 1923 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 1924 ** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which 1925 ** is not the case if we are accounting for leap seconds. 1926 ** So, we provide the following conversion routines for use 1927 ** when exchanging timestamps with POSIX conforming systems. 1928 */ 1929 1930 static long 1931 leapcorr(time_t *timep) 1932 { 1933 struct state * sp; 1934 struct lsinfo * lp; 1935 int i; 1936 1937 sp = lclptr; 1938 i = sp->leapcnt; 1939 while (--i >= 0) { 1940 lp = &sp->lsis[i]; 1941 if (*timep >= lp->ls_trans) 1942 return lp->ls_corr; 1943 } 1944 return 0; 1945 } 1946 1947 time_t 1948 time2posix(time_t t) 1949 { 1950 tzset(); 1951 return t - leapcorr(&t); 1952 } 1953 1954 time_t 1955 posix2time(time_t t) 1956 { 1957 time_t x; 1958 time_t y; 1959 1960 tzset(); 1961 /* 1962 ** For a positive leap second hit, the result 1963 ** is not unique. For a negative leap second 1964 ** hit, the corresponding time doesn't exist, 1965 ** so we return an adjacent second. 1966 */ 1967 x = t + leapcorr(&t); 1968 y = x - leapcorr(&x); 1969 if (y < t) { 1970 do { 1971 x++; 1972 y = x - leapcorr(&x); 1973 } while (y < t); 1974 if (t != y) 1975 return x - 1; 1976 } else if (y > t) { 1977 do { 1978 --x; 1979 y = x - leapcorr(&x); 1980 } while (y > t); 1981 if (t != y) 1982 return x + 1; 1983 } 1984 return x; 1985 } 1986