localtime.c revision 1.50
1 /* $NetBSD: localtime.c,v 1.50 2010/12/17 23:11:57 christos Exp $ */ 2 3 /* 4 ** This file is in the public domain, so clarified as of 5 ** 1996-06-05 by Arthur David Olson. 6 */ 7 8 #include <sys/cdefs.h> 9 #if defined(LIBC_SCCS) && !defined(lint) 10 #if 0 11 static char elsieid[] = "@(#)localtime.c 8.9"; 12 #else 13 __RCSID("$NetBSD: localtime.c,v 1.50 2010/12/17 23:11:57 christos Exp $"); 14 #endif 15 #endif /* LIBC_SCCS and not lint */ 16 17 /* 18 ** Leap second handling from Bradley White. 19 ** POSIX-style TZ environment variable handling from Guy Harris. 20 */ 21 22 /*LINTLIBRARY*/ 23 24 #include "namespace.h" 25 #include "private.h" 26 #include "tzfile.h" 27 #include "fcntl.h" 28 #include "reentrant.h" 29 30 #if defined(__weak_alias) 31 __weak_alias(ctime_r,_ctime_r) 32 __weak_alias(ctime_rz,_ctime_rz) 33 __weak_alias(daylight,_daylight) 34 __weak_alias(mktime_z,_mktime_z) 35 __weak_alias(localtime_r,_localtime_r) 36 __weak_alias(localtime_rz,_localtime_rz) 37 __weak_alias(posix2time,_posix2time) 38 __weak_alias(posix2time_z,_posix2time_z) 39 __weak_alias(tzname,_tzname) 40 #endif 41 42 #include "float.h" /* for FLT_MAX and DBL_MAX */ 43 44 #ifndef TZ_ABBR_MAX_LEN 45 #define TZ_ABBR_MAX_LEN 16 46 #endif /* !defined TZ_ABBR_MAX_LEN */ 47 48 #ifndef TZ_ABBR_CHAR_SET 49 #define TZ_ABBR_CHAR_SET \ 50 "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 :+-._" 51 #endif /* !defined TZ_ABBR_CHAR_SET */ 52 53 #ifndef TZ_ABBR_ERR_CHAR 54 #define TZ_ABBR_ERR_CHAR '_' 55 #endif /* !defined TZ_ABBR_ERR_CHAR */ 56 57 /* 58 ** SunOS 4.1.1 headers lack O_BINARY. 59 */ 60 61 #ifdef O_BINARY 62 #define OPEN_MODE (O_RDONLY | O_BINARY) 63 #endif /* defined O_BINARY */ 64 #ifndef O_BINARY 65 #define OPEN_MODE O_RDONLY 66 #endif /* !defined O_BINARY */ 67 68 #ifndef WILDABBR 69 /* 70 ** Someone might make incorrect use of a time zone abbreviation: 71 ** 1. They might reference tzname[0] before calling tzset (explicitly 72 ** or implicitly). 73 ** 2. They might reference tzname[1] before calling tzset (explicitly 74 ** or implicitly). 75 ** 3. They might reference tzname[1] after setting to a time zone 76 ** in which Daylight Saving Time is never observed. 77 ** 4. They might reference tzname[0] after setting to a time zone 78 ** in which Standard Time is never observed. 79 ** 5. They might reference tm.TM_ZONE after calling offtime. 80 ** What's best to do in the above cases is open to debate; 81 ** for now, we just set things up so that in any of the five cases 82 ** WILDABBR is used. Another possibility: initialize tzname[0] to the 83 ** string "tzname[0] used before set", and similarly for the other cases. 84 ** And another: initialize tzname[0] to "ERA", with an explanation in the 85 ** manual page of what this "time zone abbreviation" means (doing this so 86 ** that tzname[0] has the "normal" length of three characters). 87 */ 88 #define WILDABBR " " 89 #endif /* !defined WILDABBR */ 90 91 static const char wildabbr[] = WILDABBR; 92 93 static char gmt[] = "GMT"; 94 95 /* 96 ** The DST rules to use if TZ has no rules and we can't load TZDEFRULES. 97 ** We default to US rules as of 1999-08-17. 98 ** POSIX 1003.1 section 8.1.1 says that the default DST rules are 99 ** implementation dependent; for historical reasons, US rules are a 100 ** common default. 101 */ 102 #ifndef TZDEFRULESTRING 103 #define TZDEFRULESTRING ",M4.1.0,M10.5.0" 104 #endif /* !defined TZDEFDST */ 105 106 struct ttinfo { /* time type information */ 107 long tt_gmtoff; /* UTC offset in seconds */ 108 int tt_isdst; /* used to set tm_isdst */ 109 int tt_abbrind; /* abbreviation list index */ 110 int tt_ttisstd; /* TRUE if transition is std time */ 111 int tt_ttisgmt; /* TRUE if transition is UTC */ 112 }; 113 114 struct lsinfo { /* leap second information */ 115 time_t ls_trans; /* transition time */ 116 long ls_corr; /* correction to apply */ 117 }; 118 119 #define BIGGEST(a, b) (((a) > (b)) ? (a) : (b)) 120 121 #ifdef TZNAME_MAX 122 #define MY_TZNAME_MAX TZNAME_MAX 123 #endif /* defined TZNAME_MAX */ 124 #ifndef TZNAME_MAX 125 #define MY_TZNAME_MAX 255 126 #endif /* !defined TZNAME_MAX */ 127 128 struct __state { 129 int leapcnt; 130 int timecnt; 131 int typecnt; 132 int charcnt; 133 int goback; 134 int goahead; 135 time_t ats[TZ_MAX_TIMES]; 136 unsigned char types[TZ_MAX_TIMES]; 137 struct ttinfo ttis[TZ_MAX_TYPES]; 138 char chars[/*CONSTCOND*/BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt), 139 (2 * (MY_TZNAME_MAX + 1)))]; 140 struct lsinfo lsis[TZ_MAX_LEAPS]; 141 }; 142 143 struct rule { 144 int r_type; /* type of rule--see below */ 145 int r_day; /* day number of rule */ 146 int r_week; /* week number of rule */ 147 int r_mon; /* month number of rule */ 148 long r_time; /* transition time of rule */ 149 }; 150 151 #define JULIAN_DAY 0 /* Jn - Julian day */ 152 #define DAY_OF_YEAR 1 /* n - day of year */ 153 #define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */ 154 155 typedef struct tm *(*subfun_t)(const timezone_t sp, const time_t *timep, 156 long offset, struct tm *tmp); 157 158 /* 159 ** Prototypes for static functions. 160 */ 161 162 static long detzcode(const char * codep); 163 static time_t detzcode64(const char * codep); 164 static int differ_by_repeat(time_t t1, time_t t0); 165 static const char * getzname(const char * strp); 166 static const char * getqzname(const char * strp, const int delim); 167 static const char * getnum(const char * strp, int * nump, int min, 168 int max); 169 static const char * getsecs(const char * strp, long * secsp); 170 static const char * getoffset(const char * strp, long * offsetp); 171 static const char * getrule(const char * strp, struct rule * rulep); 172 static void gmtload(timezone_t sp); 173 static struct tm * gmtsub(const timezone_t sp, const time_t *timep, 174 long offset, struct tm * tmp); 175 static struct tm * localsub(const timezone_t sp, const time_t *timep, 176 long offset, struct tm *tmp); 177 static int increment_overflow(int * number, int delta); 178 static int leaps_thru_end_of(int y); 179 static int long_increment_overflow(long * number, int delta); 180 static int long_normalize_overflow(long * tensptr, 181 int * unitsptr, int base); 182 static int normalize_overflow(int * tensptr, int * unitsptr, 183 int base); 184 static void settzname(void); 185 static time_t time1(const timezone_t sp, struct tm * const tmp, 186 subfun_t funcp, long offset); 187 static time_t time2(const timezone_t sp, struct tm * const tmp, 188 subfun_t funcp, 189 const long offset, int *const okayp); 190 static time_t time2sub(const timezone_t sp, struct tm * consttmp, 191 subfun_t funcp, const long offset, 192 int *const okayp, const int do_norm_secs); 193 static struct tm * timesub(const timezone_t sp, const time_t * timep, 194 long offset, struct tm * tmp); 195 static int tmcomp(const struct tm * atmp, 196 const struct tm * btmp); 197 static time_t transtime(time_t janfirst, int year, 198 const struct rule * rulep, long offset); 199 static int typesequiv(const timezone_t sp, int a, int b); 200 static int tzload(timezone_t sp, const char * name, 201 int doextend); 202 static int tzparse(timezone_t sp, const char * name, 203 int lastditch); 204 static void tzset_unlocked(void); 205 static void tzsetwall_unlocked(void); 206 static long leapcorr(const timezone_t sp, time_t * timep); 207 208 static timezone_t lclptr; 209 static timezone_t gmtptr; 210 211 #ifndef TZ_STRLEN_MAX 212 #define TZ_STRLEN_MAX 255 213 #endif /* !defined TZ_STRLEN_MAX */ 214 215 static char lcl_TZname[TZ_STRLEN_MAX + 1]; 216 static int lcl_is_set; 217 static int gmt_is_set; 218 219 #if !defined(__LIBC12_SOURCE__) 220 221 __aconst char * tzname[2] = { 222 (__aconst char *)__UNCONST(wildabbr), 223 (__aconst char *)__UNCONST(wildabbr) 224 }; 225 226 #else 227 228 extern __aconst char * tzname[2]; 229 230 #endif 231 232 #ifdef _REENTRANT 233 static rwlock_t lcl_lock = RWLOCK_INITIALIZER; 234 #endif 235 236 /* 237 ** Section 4.12.3 of X3.159-1989 requires that 238 ** Except for the strftime function, these functions [asctime, 239 ** ctime, gmtime, localtime] return values in one of two static 240 ** objects: a broken-down time structure and an array of char. 241 ** Thanks to Paul Eggert for noting this. 242 */ 243 244 static struct tm tm; 245 246 #ifdef USG_COMPAT 247 #if !defined(__LIBC12_SOURCE__) 248 long timezone = 0; 249 int daylight = 0; 250 #else 251 extern int daylight; 252 extern long timezone __RENAME(__timezone13); 253 #endif 254 #endif /* defined USG_COMPAT */ 255 256 #ifdef ALTZONE 257 time_t altzone = 0; 258 #endif /* defined ALTZONE */ 259 260 static long 261 detzcode(const char *const codep) 262 { 263 long result; 264 int i; 265 266 result = (codep[0] & 0x80) ? ~0L : 0; 267 for (i = 0; i < 4; ++i) 268 result = (result << 8) | (codep[i] & 0xff); 269 return result; 270 } 271 272 static time_t 273 detzcode64(const char *const codep) 274 { 275 time_t result; 276 int i; 277 278 result = (codep[0] & 0x80) ? -1 : 0; 279 for (i = 0; i < 8; ++i) 280 result = result * 256 + (codep[i] & 0xff); 281 return result; 282 } 283 284 const char * 285 tzgetname(const timezone_t sp, int isdst) 286 { 287 int i; 288 for (i = 0; i < sp->timecnt; ++i) { 289 const struct ttinfo *const ttisp = &sp->ttis[sp->types[i]]; 290 291 if (ttisp->tt_isdst == isdst) 292 return &sp->chars[ttisp->tt_abbrind]; 293 } 294 return NULL; 295 } 296 297 static void 298 settzname_z(timezone_t sp) 299 { 300 int i; 301 302 /* 303 ** Scrub the abbreviations. 304 ** First, replace bogus characters. 305 */ 306 for (i = 0; i < sp->charcnt; ++i) 307 if (strchr(TZ_ABBR_CHAR_SET, sp->chars[i]) == NULL) 308 sp->chars[i] = TZ_ABBR_ERR_CHAR; 309 /* 310 ** Second, truncate long abbreviations. 311 */ 312 for (i = 0; i < sp->typecnt; ++i) { 313 const struct ttinfo * const ttisp = &sp->ttis[i]; 314 char * cp = &sp->chars[ttisp->tt_abbrind]; 315 316 if (strlen(cp) > TZ_ABBR_MAX_LEN && 317 strcmp(cp, GRANDPARENTED) != 0) 318 *(cp + TZ_ABBR_MAX_LEN) = '\0'; 319 } 320 } 321 322 static void 323 settzname(void) 324 { 325 timezone_t const sp = lclptr; 326 int i; 327 328 tzname[0] = (__aconst char *)__UNCONST(wildabbr); 329 tzname[1] = (__aconst char *)__UNCONST(wildabbr); 330 #ifdef USG_COMPAT 331 daylight = 0; 332 timezone = 0; 333 #endif /* defined USG_COMPAT */ 334 #ifdef ALTZONE 335 altzone = 0; 336 #endif /* defined ALTZONE */ 337 if (sp == NULL) { 338 tzname[0] = tzname[1] = (__aconst char *)__UNCONST(gmt); 339 return; 340 } 341 for (i = 0; i < sp->typecnt; ++i) { 342 const struct ttinfo * const ttisp = &sp->ttis[i]; 343 344 tzname[ttisp->tt_isdst] = 345 &sp->chars[ttisp->tt_abbrind]; 346 #ifdef USG_COMPAT 347 if (ttisp->tt_isdst) 348 daylight = 1; 349 if (i == 0 || !ttisp->tt_isdst) 350 timezone = -(ttisp->tt_gmtoff); 351 #endif /* defined USG_COMPAT */ 352 #ifdef ALTZONE 353 if (i == 0 || ttisp->tt_isdst) 354 altzone = -(ttisp->tt_gmtoff); 355 #endif /* defined ALTZONE */ 356 } 357 /* 358 ** And to get the latest zone names into tzname. . . 359 */ 360 for (i = 0; i < sp->timecnt; ++i) { 361 register const struct ttinfo * const ttisp = 362 &sp->ttis[ 363 sp->types[i]]; 364 365 tzname[ttisp->tt_isdst] = 366 &sp->chars[ttisp->tt_abbrind]; 367 } 368 settzname_z(sp); 369 } 370 371 static int 372 differ_by_repeat(const time_t t1, const time_t t0) 373 { 374 /* CONSTCOND */ 375 if (TYPE_INTEGRAL(time_t) && 376 TYPE_BIT(time_t) - TYPE_SIGNED(time_t) < SECSPERREPEAT_BITS) 377 return 0; 378 return (int_fast64_t)t1 - (int_fast64_t)t0 == SECSPERREPEAT; 379 } 380 381 static int 382 tzload(timezone_t sp, const char *name, const int doextend) 383 { 384 const char * p; 385 int i; 386 int fid; 387 int stored; 388 int nread; 389 union { 390 struct tzhead tzhead; 391 char buf[2 * sizeof(struct tzhead) + 392 2 * sizeof *sp + 393 4 * TZ_MAX_TIMES]; 394 } u; 395 396 sp->goback = sp->goahead = FALSE; 397 if (name == NULL && (name = TZDEFAULT) == NULL) 398 return -1; 399 { 400 int doaccess; 401 /* 402 ** Section 4.9.1 of the C standard says that 403 ** "FILENAME_MAX expands to an integral constant expression 404 ** that is the size needed for an array of char large enough 405 ** to hold the longest file name string that the implementation 406 ** guarantees can be opened." 407 */ 408 char fullname[FILENAME_MAX + 1]; 409 410 if (name[0] == ':') 411 ++name; 412 doaccess = name[0] == '/'; 413 if (!doaccess) { 414 if ((p = TZDIR) == NULL) 415 return -1; 416 if ((strlen(p) + strlen(name) + 1) >= sizeof fullname) 417 return -1; 418 (void) strcpy(fullname, p); /* XXX strcpy is safe */ 419 (void) strcat(fullname, "/"); /* XXX strcat is safe */ 420 (void) strcat(fullname, name); /* XXX strcat is safe */ 421 /* 422 ** Set doaccess if '.' (as in "../") shows up in name. 423 */ 424 if (strchr(name, '.') != NULL) 425 doaccess = TRUE; 426 name = fullname; 427 } 428 if (doaccess && access(name, R_OK) != 0) 429 return -1; 430 /* 431 * XXX potential security problem here if user of a set-id 432 * program has set TZ (which is passed in as name) here, 433 * and uses a race condition trick to defeat the access(2) 434 * above. 435 */ 436 if ((fid = open(name, OPEN_MODE)) == -1) 437 return -1; 438 } 439 nread = read(fid, u.buf, sizeof u.buf); 440 if (close(fid) < 0 || nread <= 0) 441 return -1; 442 for (stored = 4; stored <= 8; stored *= 2) { 443 int ttisstdcnt; 444 int ttisgmtcnt; 445 446 ttisstdcnt = (int) detzcode(u.tzhead.tzh_ttisstdcnt); 447 ttisgmtcnt = (int) detzcode(u.tzhead.tzh_ttisgmtcnt); 448 sp->leapcnt = (int) detzcode(u.tzhead.tzh_leapcnt); 449 sp->timecnt = (int) detzcode(u.tzhead.tzh_timecnt); 450 sp->typecnt = (int) detzcode(u.tzhead.tzh_typecnt); 451 sp->charcnt = (int) detzcode(u.tzhead.tzh_charcnt); 452 p = u.tzhead.tzh_charcnt + sizeof u.tzhead.tzh_charcnt; 453 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS || 454 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES || 455 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES || 456 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS || 457 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) || 458 (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0)) 459 return -1; 460 if (nread - (p - u.buf) < 461 sp->timecnt * stored + /* ats */ 462 sp->timecnt + /* types */ 463 sp->typecnt * 6 + /* ttinfos */ 464 sp->charcnt + /* chars */ 465 sp->leapcnt * (stored + 4) + /* lsinfos */ 466 ttisstdcnt + /* ttisstds */ 467 ttisgmtcnt) /* ttisgmts */ 468 return -1; 469 for (i = 0; i < sp->timecnt; ++i) { 470 sp->ats[i] = (stored == 4) ? 471 detzcode(p) : detzcode64(p); 472 p += stored; 473 } 474 for (i = 0; i < sp->timecnt; ++i) { 475 sp->types[i] = (unsigned char) *p++; 476 if (sp->types[i] >= sp->typecnt) 477 return -1; 478 } 479 for (i = 0; i < sp->typecnt; ++i) { 480 struct ttinfo * ttisp; 481 482 ttisp = &sp->ttis[i]; 483 ttisp->tt_gmtoff = detzcode(p); 484 p += 4; 485 ttisp->tt_isdst = (unsigned char) *p++; 486 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1) 487 return -1; 488 ttisp->tt_abbrind = (unsigned char) *p++; 489 if (ttisp->tt_abbrind < 0 || 490 ttisp->tt_abbrind > sp->charcnt) 491 return -1; 492 } 493 for (i = 0; i < sp->charcnt; ++i) 494 sp->chars[i] = *p++; 495 sp->chars[i] = '\0'; /* ensure '\0' at end */ 496 for (i = 0; i < sp->leapcnt; ++i) { 497 struct lsinfo * lsisp; 498 499 lsisp = &sp->lsis[i]; 500 lsisp->ls_trans = (stored == 4) ? 501 detzcode(p) : detzcode64(p); 502 p += stored; 503 lsisp->ls_corr = detzcode(p); 504 p += 4; 505 } 506 for (i = 0; i < sp->typecnt; ++i) { 507 struct ttinfo * ttisp; 508 509 ttisp = &sp->ttis[i]; 510 if (ttisstdcnt == 0) 511 ttisp->tt_ttisstd = FALSE; 512 else { 513 ttisp->tt_ttisstd = *p++; 514 if (ttisp->tt_ttisstd != TRUE && 515 ttisp->tt_ttisstd != FALSE) 516 return -1; 517 } 518 } 519 for (i = 0; i < sp->typecnt; ++i) { 520 struct ttinfo * ttisp; 521 522 ttisp = &sp->ttis[i]; 523 if (ttisgmtcnt == 0) 524 ttisp->tt_ttisgmt = FALSE; 525 else { 526 ttisp->tt_ttisgmt = *p++; 527 if (ttisp->tt_ttisgmt != TRUE && 528 ttisp->tt_ttisgmt != FALSE) 529 return -1; 530 } 531 } 532 /* 533 ** Out-of-sort ats should mean we're running on a 534 ** signed time_t system but using a data file with 535 ** unsigned values (or vice versa). 536 */ 537 for (i = 0; i < sp->timecnt - 2; ++i) 538 if (sp->ats[i] > sp->ats[i + 1]) { 539 ++i; 540 /* CONSTCOND */ 541 if (TYPE_SIGNED(time_t)) { 542 /* 543 ** Ignore the end (easy). 544 */ 545 sp->timecnt = i; 546 } else { 547 /* 548 ** Ignore the beginning (harder). 549 */ 550 int j; 551 552 for (j = 0; j + i < sp->timecnt; ++j) { 553 sp->ats[j] = sp->ats[j + i]; 554 sp->types[j] = sp->types[j + i]; 555 } 556 sp->timecnt = j; 557 } 558 break; 559 } 560 /* 561 ** If this is an old file, we're done. 562 */ 563 if (u.tzhead.tzh_version[0] == '\0') 564 break; 565 nread -= p - u.buf; 566 for (i = 0; i < nread; ++i) 567 u.buf[i] = p[i]; 568 /* 569 ** If this is a narrow integer time_t system, we're done. 570 */ 571 if (stored >= (int) sizeof(time_t) 572 /* CONSTCOND */ 573 && TYPE_INTEGRAL(time_t)) 574 break; 575 } 576 if (doextend && nread > 2 && 577 u.buf[0] == '\n' && u.buf[nread - 1] == '\n' && 578 sp->typecnt + 2 <= TZ_MAX_TYPES) { 579 struct __state ts; 580 int result; 581 582 u.buf[nread - 1] = '\0'; 583 result = tzparse(&ts, &u.buf[1], FALSE); 584 if (result == 0 && ts.typecnt == 2 && 585 sp->charcnt + ts.charcnt <= TZ_MAX_CHARS) { 586 for (i = 0; i < 2; ++i) 587 ts.ttis[i].tt_abbrind += 588 sp->charcnt; 589 for (i = 0; i < ts.charcnt; ++i) 590 sp->chars[sp->charcnt++] = 591 ts.chars[i]; 592 i = 0; 593 while (i < ts.timecnt && 594 ts.ats[i] <= 595 sp->ats[sp->timecnt - 1]) 596 ++i; 597 while (i < ts.timecnt && 598 sp->timecnt < TZ_MAX_TIMES) { 599 sp->ats[sp->timecnt] = 600 ts.ats[i]; 601 sp->types[sp->timecnt] = 602 sp->typecnt + 603 ts.types[i]; 604 ++sp->timecnt; 605 ++i; 606 } 607 sp->ttis[sp->typecnt++] = ts.ttis[0]; 608 sp->ttis[sp->typecnt++] = ts.ttis[1]; 609 } 610 } 611 if (sp->timecnt > 1) { 612 for (i = 1; i < sp->timecnt; ++i) 613 if (typesequiv(sp, sp->types[i], sp->types[0]) && 614 differ_by_repeat(sp->ats[i], sp->ats[0])) { 615 sp->goback = TRUE; 616 break; 617 } 618 for (i = sp->timecnt - 2; i >= 0; --i) 619 if (typesequiv(sp, sp->types[sp->timecnt - 1], 620 sp->types[i]) && 621 differ_by_repeat(sp->ats[sp->timecnt - 1], 622 sp->ats[i])) { 623 sp->goahead = TRUE; 624 break; 625 } 626 } 627 return 0; 628 } 629 630 static int 631 typesequiv(const timezone_t sp, const int a, const int b) 632 { 633 int result; 634 635 if (sp == NULL || 636 a < 0 || a >= sp->typecnt || 637 b < 0 || b >= sp->typecnt) 638 result = FALSE; 639 else { 640 const struct ttinfo * ap = &sp->ttis[a]; 641 const struct ttinfo * bp = &sp->ttis[b]; 642 result = ap->tt_gmtoff == bp->tt_gmtoff && 643 ap->tt_isdst == bp->tt_isdst && 644 ap->tt_ttisstd == bp->tt_ttisstd && 645 ap->tt_ttisgmt == bp->tt_ttisgmt && 646 strcmp(&sp->chars[ap->tt_abbrind], 647 &sp->chars[bp->tt_abbrind]) == 0; 648 } 649 return result; 650 } 651 652 static const int mon_lengths[2][MONSPERYEAR] = { 653 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, 654 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } 655 }; 656 657 static const int year_lengths[2] = { 658 DAYSPERNYEAR, DAYSPERLYEAR 659 }; 660 661 /* 662 ** Given a pointer into a time zone string, scan until a character that is not 663 ** a valid character in a zone name is found. Return a pointer to that 664 ** character. 665 */ 666 667 static const char * 668 getzname(strp) 669 const char * strp; 670 { 671 char c; 672 673 while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && 674 c != '+') 675 ++strp; 676 return strp; 677 } 678 679 /* 680 ** Given a pointer into an extended time zone string, scan until the ending 681 ** delimiter of the zone name is located. Return a pointer to the delimiter. 682 ** 683 ** As with getzname above, the legal character set is actually quite 684 ** restricted, with other characters producing undefined results. 685 ** We don't do any checking here; checking is done later in common-case code. 686 */ 687 688 static const char * 689 getqzname(const char *strp, const int delim) 690 { 691 int c; 692 693 while ((c = *strp) != '\0' && c != delim) 694 ++strp; 695 return strp; 696 } 697 698 /* 699 ** Given a pointer into a time zone string, extract a number from that string. 700 ** Check that the number is within a specified range; if it is not, return 701 ** NULL. 702 ** Otherwise, return a pointer to the first character not part of the number. 703 */ 704 705 static const char * 706 getnum(strp, nump, min, max) 707 const char * strp; 708 int * const nump; 709 const int min; 710 const int max; 711 { 712 char c; 713 int num; 714 715 if (strp == NULL || !is_digit(c = *strp)) { 716 errno = EINVAL; 717 return NULL; 718 } 719 num = 0; 720 do { 721 num = num * 10 + (c - '0'); 722 if (num > max) { 723 errno = EOVERFLOW; 724 return NULL; /* illegal value */ 725 } 726 c = *++strp; 727 } while (is_digit(c)); 728 if (num < min) { 729 errno = EINVAL; 730 return NULL; /* illegal value */ 731 } 732 *nump = num; 733 return strp; 734 } 735 736 /* 737 ** Given a pointer into a time zone string, extract a number of seconds, 738 ** in hh[:mm[:ss]] form, from the string. 739 ** If any error occurs, return NULL. 740 ** Otherwise, return a pointer to the first character not part of the number 741 ** of seconds. 742 */ 743 744 static const char * 745 getsecs(const char *strp, long *const secsp) 746 { 747 int num; 748 749 /* 750 ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like 751 ** "M10.4.6/26", which does not conform to Posix, 752 ** but which specifies the equivalent of 753 ** ``02:00 on the first Sunday on or after 23 Oct''. 754 */ 755 strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); 756 if (strp == NULL) 757 return NULL; 758 *secsp = num * (long) SECSPERHOUR; 759 if (*strp == ':') { 760 ++strp; 761 strp = getnum(strp, &num, 0, MINSPERHOUR - 1); 762 if (strp == NULL) 763 return NULL; 764 *secsp += num * SECSPERMIN; 765 if (*strp == ':') { 766 ++strp; 767 /* `SECSPERMIN' allows for leap seconds. */ 768 strp = getnum(strp, &num, 0, SECSPERMIN); 769 if (strp == NULL) 770 return NULL; 771 *secsp += num; 772 } 773 } 774 return strp; 775 } 776 777 /* 778 ** Given a pointer into a time zone string, extract an offset, in 779 ** [+-]hh[:mm[:ss]] form, from the string. 780 ** If any error occurs, return NULL. 781 ** Otherwise, return a pointer to the first character not part of the time. 782 */ 783 784 static const char * 785 getoffset(const char *strp, long *const offsetp) 786 { 787 int neg = 0; 788 789 if (*strp == '-') { 790 neg = 1; 791 ++strp; 792 } else if (*strp == '+') 793 ++strp; 794 strp = getsecs(strp, offsetp); 795 if (strp == NULL) 796 return NULL; /* illegal time */ 797 if (neg) 798 *offsetp = -*offsetp; 799 return strp; 800 } 801 802 /* 803 ** Given a pointer into a time zone string, extract a rule in the form 804 ** date[/time]. See POSIX section 8 for the format of "date" and "time". 805 ** If a valid rule is not found, return NULL. 806 ** Otherwise, return a pointer to the first character not part of the rule. 807 */ 808 809 static const char * 810 getrule(const char *strp, struct rule *const rulep) 811 { 812 if (*strp == 'J') { 813 /* 814 ** Julian day. 815 */ 816 rulep->r_type = JULIAN_DAY; 817 ++strp; 818 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); 819 } else if (*strp == 'M') { 820 /* 821 ** Month, week, day. 822 */ 823 rulep->r_type = MONTH_NTH_DAY_OF_WEEK; 824 ++strp; 825 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); 826 if (strp == NULL) 827 return NULL; 828 if (*strp++ != '.') 829 return NULL; 830 strp = getnum(strp, &rulep->r_week, 1, 5); 831 if (strp == NULL) 832 return NULL; 833 if (*strp++ != '.') 834 return NULL; 835 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); 836 } else if (is_digit(*strp)) { 837 /* 838 ** Day of year. 839 */ 840 rulep->r_type = DAY_OF_YEAR; 841 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); 842 } else return NULL; /* invalid format */ 843 if (strp == NULL) 844 return NULL; 845 if (*strp == '/') { 846 /* 847 ** Time specified. 848 */ 849 ++strp; 850 strp = getsecs(strp, &rulep->r_time); 851 } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ 852 return strp; 853 } 854 855 /* 856 ** Given the Epoch-relative time of January 1, 00:00:00 UTC, in a year, the 857 ** year, a rule, and the offset from UTC at the time that rule takes effect, 858 ** calculate the Epoch-relative time that rule takes effect. 859 */ 860 861 static time_t 862 transtime(const time_t janfirst, const int year, const struct rule *const rulep, 863 const long offset) 864 { 865 int leapyear; 866 time_t value; 867 int i; 868 int d, m1, yy0, yy1, yy2, dow; 869 870 INITIALIZE(value); 871 leapyear = isleap(year); 872 switch (rulep->r_type) { 873 874 case JULIAN_DAY: 875 /* 876 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap 877 ** years. 878 ** In non-leap years, or if the day number is 59 or less, just 879 ** add SECSPERDAY times the day number-1 to the time of 880 ** January 1, midnight, to get the day. 881 */ 882 value = janfirst + (rulep->r_day - 1) * SECSPERDAY; 883 if (leapyear && rulep->r_day >= 60) 884 value += SECSPERDAY; 885 break; 886 887 case DAY_OF_YEAR: 888 /* 889 ** n - day of year. 890 ** Just add SECSPERDAY times the day number to the time of 891 ** January 1, midnight, to get the day. 892 */ 893 value = janfirst + rulep->r_day * SECSPERDAY; 894 break; 895 896 case MONTH_NTH_DAY_OF_WEEK: 897 /* 898 ** Mm.n.d - nth "dth day" of month m. 899 */ 900 value = janfirst; 901 for (i = 0; i < rulep->r_mon - 1; ++i) 902 value += mon_lengths[leapyear][i] * SECSPERDAY; 903 904 /* 905 ** Use Zeller's Congruence to get day-of-week of first day of 906 ** month. 907 */ 908 m1 = (rulep->r_mon + 9) % 12 + 1; 909 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; 910 yy1 = yy0 / 100; 911 yy2 = yy0 % 100; 912 dow = ((26 * m1 - 2) / 10 + 913 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; 914 if (dow < 0) 915 dow += DAYSPERWEEK; 916 917 /* 918 ** "dow" is the day-of-week of the first day of the month. Get 919 ** the day-of-month (zero-origin) of the first "dow" day of the 920 ** month. 921 */ 922 d = rulep->r_day - dow; 923 if (d < 0) 924 d += DAYSPERWEEK; 925 for (i = 1; i < rulep->r_week; ++i) { 926 if (d + DAYSPERWEEK >= 927 mon_lengths[leapyear][rulep->r_mon - 1]) 928 break; 929 d += DAYSPERWEEK; 930 } 931 932 /* 933 ** "d" is the day-of-month (zero-origin) of the day we want. 934 */ 935 value += d * SECSPERDAY; 936 break; 937 } 938 939 /* 940 ** "value" is the Epoch-relative time of 00:00:00 UTC on the day in 941 ** question. To get the Epoch-relative time of the specified local 942 ** time on that day, add the transition time and the current offset 943 ** from UTC. 944 */ 945 return value + rulep->r_time + offset; 946 } 947 948 /* 949 ** Given a POSIX section 8-style TZ string, fill in the rule tables as 950 ** appropriate. 951 */ 952 953 static int 954 tzparse(timezone_t sp, const char *name, const int lastditch) 955 { 956 const char * stdname; 957 const char * dstname; 958 size_t stdlen; 959 size_t dstlen; 960 long stdoffset; 961 long dstoffset; 962 time_t * atp; 963 unsigned char * typep; 964 char * cp; 965 int load_result; 966 967 INITIALIZE(dstname); 968 stdname = name; 969 if (lastditch) { 970 stdlen = strlen(name); /* length of standard zone name */ 971 name += stdlen; 972 if (stdlen >= sizeof sp->chars) 973 stdlen = (sizeof sp->chars) - 1; 974 stdoffset = 0; 975 } else { 976 if (*name == '<') { 977 name++; 978 stdname = name; 979 name = getqzname(name, '>'); 980 if (*name != '>') 981 return (-1); 982 stdlen = name - stdname; 983 name++; 984 } else { 985 name = getzname(name); 986 stdlen = name - stdname; 987 } 988 if (*name == '\0') 989 return -1; 990 name = getoffset(name, &stdoffset); 991 if (name == NULL) 992 return -1; 993 } 994 load_result = tzload(sp, TZDEFRULES, FALSE); 995 if (load_result != 0) 996 sp->leapcnt = 0; /* so, we're off a little */ 997 if (*name != '\0') { 998 if (*name == '<') { 999 dstname = ++name; 1000 name = getqzname(name, '>'); 1001 if (*name != '>') 1002 return -1; 1003 dstlen = name - dstname; 1004 name++; 1005 } else { 1006 dstname = name; 1007 name = getzname(name); 1008 dstlen = name - dstname; /* length of DST zone name */ 1009 } 1010 if (*name != '\0' && *name != ',' && *name != ';') { 1011 name = getoffset(name, &dstoffset); 1012 if (name == NULL) 1013 return -1; 1014 } else dstoffset = stdoffset - SECSPERHOUR; 1015 if (*name == '\0' && load_result != 0) 1016 name = TZDEFRULESTRING; 1017 if (*name == ',' || *name == ';') { 1018 struct rule start; 1019 struct rule end; 1020 int year; 1021 time_t janfirst; 1022 time_t starttime; 1023 time_t endtime; 1024 1025 ++name; 1026 if ((name = getrule(name, &start)) == NULL) 1027 return -1; 1028 if (*name++ != ',') 1029 return -1; 1030 if ((name = getrule(name, &end)) == NULL) 1031 return -1; 1032 if (*name != '\0') 1033 return -1; 1034 sp->typecnt = 2; /* standard time and DST */ 1035 /* 1036 ** Two transitions per year, from EPOCH_YEAR forward. 1037 */ 1038 sp->ttis[0].tt_gmtoff = -dstoffset; 1039 sp->ttis[0].tt_isdst = 1; 1040 sp->ttis[0].tt_abbrind = stdlen + 1; 1041 sp->ttis[1].tt_gmtoff = -stdoffset; 1042 sp->ttis[1].tt_isdst = 0; 1043 sp->ttis[1].tt_abbrind = 0; 1044 atp = sp->ats; 1045 typep = sp->types; 1046 janfirst = 0; 1047 sp->timecnt = 0; 1048 for (year = EPOCH_YEAR; 1049 sp->timecnt + 2 <= TZ_MAX_TIMES; 1050 ++year) { 1051 time_t newfirst; 1052 1053 starttime = transtime(janfirst, year, &start, 1054 stdoffset); 1055 endtime = transtime(janfirst, year, &end, 1056 dstoffset); 1057 if (starttime > endtime) { 1058 *atp++ = endtime; 1059 *typep++ = 1; /* DST ends */ 1060 *atp++ = starttime; 1061 *typep++ = 0; /* DST begins */ 1062 } else { 1063 *atp++ = starttime; 1064 *typep++ = 0; /* DST begins */ 1065 *atp++ = endtime; 1066 *typep++ = 1; /* DST ends */ 1067 } 1068 sp->timecnt += 2; 1069 newfirst = janfirst; 1070 newfirst += year_lengths[isleap(year)] * 1071 SECSPERDAY; 1072 if (newfirst <= janfirst) 1073 break; 1074 janfirst = newfirst; 1075 } 1076 } else { 1077 long theirstdoffset; 1078 long theirdstoffset; 1079 long theiroffset; 1080 int isdst; 1081 int i; 1082 int j; 1083 1084 if (*name != '\0') 1085 return -1; 1086 /* 1087 ** Initial values of theirstdoffset 1088 */ 1089 theirstdoffset = 0; 1090 for (i = 0; i < sp->timecnt; ++i) { 1091 j = sp->types[i]; 1092 if (!sp->ttis[j].tt_isdst) { 1093 theirstdoffset = 1094 -sp->ttis[j].tt_gmtoff; 1095 break; 1096 } 1097 } 1098 theirdstoffset = 0; 1099 for (i = 0; i < sp->timecnt; ++i) { 1100 j = sp->types[i]; 1101 if (sp->ttis[j].tt_isdst) { 1102 theirdstoffset = 1103 -sp->ttis[j].tt_gmtoff; 1104 break; 1105 } 1106 } 1107 /* 1108 ** Initially we're assumed to be in standard time. 1109 */ 1110 isdst = FALSE; 1111 theiroffset = theirstdoffset; 1112 /* 1113 ** Now juggle transition times and types 1114 ** tracking offsets as you do. 1115 */ 1116 for (i = 0; i < sp->timecnt; ++i) { 1117 j = sp->types[i]; 1118 sp->types[i] = sp->ttis[j].tt_isdst; 1119 if (sp->ttis[j].tt_ttisgmt) { 1120 /* No adjustment to transition time */ 1121 } else { 1122 /* 1123 ** If summer time is in effect, and the 1124 ** transition time was not specified as 1125 ** standard time, add the summer time 1126 ** offset to the transition time; 1127 ** otherwise, add the standard time 1128 ** offset to the transition time. 1129 */ 1130 /* 1131 ** Transitions from DST to DDST 1132 ** will effectively disappear since 1133 ** POSIX provides for only one DST 1134 ** offset. 1135 */ 1136 if (isdst && !sp->ttis[j].tt_ttisstd) { 1137 sp->ats[i] += dstoffset - 1138 theirdstoffset; 1139 } else { 1140 sp->ats[i] += stdoffset - 1141 theirstdoffset; 1142 } 1143 } 1144 theiroffset = -sp->ttis[j].tt_gmtoff; 1145 if (!sp->ttis[j].tt_isdst) 1146 theirstdoffset = theiroffset; 1147 else theirdstoffset = theiroffset; 1148 } 1149 /* 1150 ** Finally, fill in ttis. 1151 ** ttisstd and ttisgmt need not be handled. 1152 */ 1153 sp->ttis[0].tt_gmtoff = -stdoffset; 1154 sp->ttis[0].tt_isdst = FALSE; 1155 sp->ttis[0].tt_abbrind = 0; 1156 sp->ttis[1].tt_gmtoff = -dstoffset; 1157 sp->ttis[1].tt_isdst = TRUE; 1158 sp->ttis[1].tt_abbrind = stdlen + 1; 1159 sp->typecnt = 2; 1160 } 1161 } else { 1162 dstlen = 0; 1163 sp->typecnt = 1; /* only standard time */ 1164 sp->timecnt = 0; 1165 sp->ttis[0].tt_gmtoff = -stdoffset; 1166 sp->ttis[0].tt_isdst = 0; 1167 sp->ttis[0].tt_abbrind = 0; 1168 } 1169 sp->charcnt = stdlen + 1; 1170 if (dstlen != 0) 1171 sp->charcnt += dstlen + 1; 1172 if ((size_t) sp->charcnt > sizeof sp->chars) 1173 return -1; 1174 cp = sp->chars; 1175 (void) strncpy(cp, stdname, stdlen); 1176 cp += stdlen; 1177 *cp++ = '\0'; 1178 if (dstlen != 0) { 1179 (void) strncpy(cp, dstname, dstlen); 1180 *(cp + dstlen) = '\0'; 1181 } 1182 return 0; 1183 } 1184 1185 static void 1186 gmtload(timezone_t sp) 1187 { 1188 if (tzload(sp, gmt, TRUE) != 0) 1189 (void) tzparse(sp, gmt, TRUE); 1190 } 1191 1192 timezone_t 1193 tzalloc(const char *name) 1194 { 1195 timezone_t sp = calloc(1, sizeof *sp); 1196 if (sp == NULL) 1197 return NULL; 1198 if (tzload(sp, name, TRUE) != 0) { 1199 free(sp); 1200 return NULL; 1201 } 1202 settzname_z(sp); 1203 return sp; 1204 } 1205 1206 void 1207 tzfree(const timezone_t sp) 1208 { 1209 free(sp); 1210 } 1211 1212 static void 1213 tzsetwall_unlocked(void) 1214 { 1215 if (lcl_is_set < 0) 1216 return; 1217 lcl_is_set = -1; 1218 1219 if (lclptr == NULL) { 1220 int saveerrno = errno; 1221 lclptr = calloc(1, sizeof *lclptr); 1222 errno = saveerrno; 1223 if (lclptr == NULL) { 1224 settzname(); /* all we can do */ 1225 return; 1226 } 1227 } 1228 if (tzload(lclptr, NULL, TRUE) != 0) 1229 gmtload(lclptr); 1230 settzname(); 1231 } 1232 1233 #ifndef STD_INSPIRED 1234 /* 1235 ** A non-static declaration of tzsetwall in a system header file 1236 ** may cause a warning about this upcoming static declaration... 1237 */ 1238 static 1239 #endif /* !defined STD_INSPIRED */ 1240 void 1241 tzsetwall(void) 1242 { 1243 rwlock_wrlock(&lcl_lock); 1244 tzsetwall_unlocked(); 1245 rwlock_unlock(&lcl_lock); 1246 } 1247 1248 #ifndef STD_INSPIRED 1249 /* 1250 ** A non-static declaration of tzsetwall in a system header file 1251 ** may cause a warning about this upcoming static declaration... 1252 */ 1253 static 1254 #endif /* !defined STD_INSPIRED */ 1255 void 1256 tzset_unlocked(void) 1257 { 1258 const char * name; 1259 int saveerrno; 1260 1261 saveerrno = errno; 1262 name = getenv("TZ"); 1263 errno = saveerrno; 1264 if (name == NULL) { 1265 tzsetwall_unlocked(); 1266 return; 1267 } 1268 1269 if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) 1270 return; 1271 lcl_is_set = strlen(name) < sizeof lcl_TZname; 1272 if (lcl_is_set) 1273 (void)strlcpy(lcl_TZname, name, sizeof(lcl_TZname)); 1274 1275 if (lclptr == NULL) { 1276 saveerrno = errno; 1277 lclptr = calloc(1, sizeof *lclptr); 1278 errno = saveerrno; 1279 if (lclptr == NULL) { 1280 settzname(); /* all we can do */ 1281 return; 1282 } 1283 } 1284 if (*name == '\0') { 1285 /* 1286 ** User wants it fast rather than right. 1287 */ 1288 lclptr->leapcnt = 0; /* so, we're off a little */ 1289 lclptr->timecnt = 0; 1290 lclptr->typecnt = 0; 1291 lclptr->ttis[0].tt_isdst = 0; 1292 lclptr->ttis[0].tt_gmtoff = 0; 1293 lclptr->ttis[0].tt_abbrind = 0; 1294 (void) strlcpy(lclptr->chars, gmt, sizeof(lclptr->chars)); 1295 } else if (tzload(lclptr, name, TRUE) != 0) 1296 if (name[0] == ':' || tzparse(lclptr, name, FALSE) != 0) 1297 (void) gmtload(lclptr); 1298 settzname(); 1299 } 1300 1301 void 1302 tzset(void) 1303 { 1304 rwlock_wrlock(&lcl_lock); 1305 tzset_unlocked(); 1306 rwlock_unlock(&lcl_lock); 1307 } 1308 1309 /* 1310 ** The easy way to behave "as if no library function calls" localtime 1311 ** is to not call it--so we drop its guts into "localsub", which can be 1312 ** freely called. (And no, the PANS doesn't require the above behavior-- 1313 ** but it *is* desirable.) 1314 ** 1315 ** The unused offset argument is for the benefit of mktime variants. 1316 */ 1317 1318 /*ARGSUSED*/ 1319 static struct tm * 1320 localsub(const timezone_t sp, const time_t * const timep, const long offset, 1321 struct tm *const tmp) 1322 { 1323 const struct ttinfo * ttisp; 1324 int i; 1325 struct tm * result; 1326 const time_t t = *timep; 1327 1328 if ((sp->goback && t < sp->ats[0]) || 1329 (sp->goahead && t > sp->ats[sp->timecnt - 1])) { 1330 time_t newt = t; 1331 time_t seconds; 1332 time_t tcycles; 1333 int_fast64_t icycles; 1334 1335 if (t < sp->ats[0]) 1336 seconds = sp->ats[0] - t; 1337 else seconds = t - sp->ats[sp->timecnt - 1]; 1338 --seconds; 1339 tcycles = seconds / YEARSPERREPEAT / AVGSECSPERYEAR; 1340 ++tcycles; 1341 icycles = tcycles; 1342 if (tcycles - icycles >= 1 || icycles - tcycles >= 1) 1343 return NULL; 1344 seconds = (time_t) icycles; 1345 seconds *= YEARSPERREPEAT; 1346 seconds *= AVGSECSPERYEAR; 1347 if (t < sp->ats[0]) 1348 newt += seconds; 1349 else newt -= seconds; 1350 if (newt < sp->ats[0] || 1351 newt > sp->ats[sp->timecnt - 1]) { 1352 errno = EOVERFLOW; 1353 return NULL; /* "cannot happen" */ 1354 } 1355 result = localsub(sp, &newt, offset, tmp); 1356 if (result == tmp) { 1357 time_t newy; 1358 1359 newy = tmp->tm_year; 1360 if (t < sp->ats[0]) 1361 newy -= (time_t)icycles * YEARSPERREPEAT; 1362 else newy += (time_t)icycles * YEARSPERREPEAT; 1363 tmp->tm_year = (int)newy; 1364 if (tmp->tm_year != newy) { 1365 errno = EOVERFLOW; 1366 return NULL; 1367 } 1368 } 1369 return result; 1370 } 1371 if (sp->timecnt == 0 || t < sp->ats[0]) { 1372 i = 0; 1373 while (sp->ttis[i].tt_isdst) 1374 if (++i >= sp->typecnt) { 1375 i = 0; 1376 break; 1377 } 1378 } else { 1379 int lo = 1; 1380 int hi = sp->timecnt; 1381 1382 while (lo < hi) { 1383 int mid = (lo + hi) / 2; 1384 1385 if (t < sp->ats[mid]) 1386 hi = mid; 1387 else lo = mid + 1; 1388 } 1389 i = (int) sp->types[lo - 1]; 1390 } 1391 ttisp = &sp->ttis[i]; 1392 /* 1393 ** To get (wrong) behavior that's compatible with System V Release 2.0 1394 ** you'd replace the statement below with 1395 ** t += ttisp->tt_gmtoff; 1396 ** timesub(&t, 0L, sp, tmp); 1397 */ 1398 result = timesub(sp, &t, ttisp->tt_gmtoff, tmp); 1399 tmp->tm_isdst = ttisp->tt_isdst; 1400 tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind]; 1401 #ifdef TM_ZONE 1402 tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind]; 1403 #endif /* defined TM_ZONE */ 1404 return result; 1405 } 1406 1407 /* 1408 ** Re-entrant version of localtime. 1409 */ 1410 1411 struct tm * 1412 localtime_r(const time_t * __restrict timep, struct tm *tmp) 1413 { 1414 rwlock_rdlock(&lcl_lock); 1415 tzset_unlocked(); 1416 tmp = localtime_rz(lclptr, timep, tmp); 1417 rwlock_unlock(&lcl_lock); 1418 return tmp; 1419 } 1420 1421 struct tm * 1422 localtime(const time_t *const timep) 1423 { 1424 return localtime_r(timep, &tm); 1425 } 1426 1427 struct tm * 1428 localtime_rz(const timezone_t sp, const time_t * __restrict timep, struct tm *tmp) 1429 { 1430 if (sp == NULL) 1431 return gmtsub(NULL, timep, 0L, tmp); 1432 else 1433 return localsub(sp, timep, 0L, tmp); 1434 } 1435 1436 /* 1437 ** gmtsub is to gmtime as localsub is to localtime. 1438 */ 1439 1440 static struct tm * 1441 gmtsub(const timezone_t sp, const time_t * const timep, const long offset, 1442 struct tm *const tmp) 1443 { 1444 struct tm * result; 1445 #ifdef _REENTRANT 1446 static mutex_t gmt_mutex = MUTEX_INITIALIZER; 1447 #endif 1448 1449 mutex_lock(&gmt_mutex); 1450 if (!gmt_is_set) { 1451 int saveerrno; 1452 gmt_is_set = TRUE; 1453 saveerrno = errno; 1454 gmtptr = calloc(1, sizeof *gmtptr); 1455 errno = saveerrno; 1456 if (gmtptr != NULL) 1457 gmtload(gmtptr); 1458 } 1459 mutex_unlock(&gmt_mutex); 1460 result = timesub(gmtptr, timep, offset, tmp); 1461 #ifdef TM_ZONE 1462 /* 1463 ** Could get fancy here and deliver something such as 1464 ** "UTC+xxxx" or "UTC-xxxx" if offset is non-zero, 1465 ** but this is no time for a treasure hunt. 1466 */ 1467 if (offset != 0) 1468 tmp->TM_ZONE = (__aconst char *)__UNCONST(wildabbr); 1469 else { 1470 if (gmtptr == NULL) 1471 tmp->TM_ZONE = (__aconst char *)__UNCONST(gmt); 1472 else tmp->TM_ZONE = gmtptr->chars; 1473 } 1474 #endif /* defined TM_ZONE */ 1475 return result; 1476 } 1477 1478 struct tm * 1479 gmtime(const time_t *const timep) 1480 { 1481 return gmtsub(NULL, timep, 0L, &tm); 1482 } 1483 1484 /* 1485 ** Re-entrant version of gmtime. 1486 */ 1487 1488 struct tm * 1489 gmtime_r(const time_t * const timep, struct tm *tmp) 1490 { 1491 return gmtsub(NULL, timep, 0L, tmp); 1492 } 1493 1494 #ifdef STD_INSPIRED 1495 1496 struct tm * 1497 offtime(const time_t *const timep, long offset) 1498 { 1499 return gmtsub(NULL, timep, offset, &tm); 1500 } 1501 1502 struct tm * 1503 offtime_r(const time_t *timep, long offset, struct tm *tmp) 1504 { 1505 return gmtsub(NULL, timep, offset, tmp); 1506 } 1507 1508 #endif /* defined STD_INSPIRED */ 1509 1510 /* 1511 ** Return the number of leap years through the end of the given year 1512 ** where, to make the math easy, the answer for year zero is defined as zero. 1513 */ 1514 1515 static int 1516 leaps_thru_end_of(const int y) 1517 { 1518 return (y >= 0) ? (y / 4 - y / 100 + y / 400) : 1519 -(leaps_thru_end_of(-(y + 1)) + 1); 1520 } 1521 1522 static struct tm * 1523 timesub(const timezone_t sp, const time_t *const timep, const long offset, 1524 struct tm *const tmp) 1525 { 1526 const struct lsinfo * lp; 1527 time_t tdays; 1528 int idays; /* unsigned would be so 2003 */ 1529 long rem; 1530 int y; 1531 const int * ip; 1532 long corr; 1533 int hit; 1534 int i; 1535 1536 corr = 0; 1537 hit = 0; 1538 i = (sp == NULL) ? 0 : sp->leapcnt; 1539 while (--i >= 0) { 1540 lp = &sp->lsis[i]; 1541 if (*timep >= lp->ls_trans) { 1542 if (*timep == lp->ls_trans) { 1543 hit = ((i == 0 && lp->ls_corr > 0) || 1544 lp->ls_corr > sp->lsis[i - 1].ls_corr); 1545 if (hit) 1546 while (i > 0 && 1547 sp->lsis[i].ls_trans == 1548 sp->lsis[i - 1].ls_trans + 1 && 1549 sp->lsis[i].ls_corr == 1550 sp->lsis[i - 1].ls_corr + 1) { 1551 ++hit; 1552 --i; 1553 } 1554 } 1555 corr = lp->ls_corr; 1556 break; 1557 } 1558 } 1559 y = EPOCH_YEAR; 1560 tdays = *timep / SECSPERDAY; 1561 rem = (long) (*timep - tdays * SECSPERDAY); 1562 while (tdays < 0 || tdays >= year_lengths[isleap(y)]) { 1563 int newy; 1564 time_t tdelta; 1565 int idelta; 1566 int leapdays; 1567 1568 tdelta = tdays / DAYSPERLYEAR; 1569 idelta = (int) tdelta; 1570 if (tdelta - idelta >= 1 || idelta - tdelta >= 1) { 1571 errno = EOVERFLOW; 1572 return NULL; 1573 } 1574 if (idelta == 0) 1575 idelta = (tdays < 0) ? -1 : 1; 1576 newy = y; 1577 if (increment_overflow(&newy, idelta)) { 1578 errno = EOVERFLOW; 1579 return NULL; 1580 } 1581 leapdays = leaps_thru_end_of(newy - 1) - 1582 leaps_thru_end_of(y - 1); 1583 tdays -= ((time_t) newy - y) * DAYSPERNYEAR; 1584 tdays -= leapdays; 1585 y = newy; 1586 } 1587 { 1588 long seconds; 1589 1590 seconds = tdays * SECSPERDAY + 0.5; 1591 tdays = seconds / SECSPERDAY; 1592 rem += (long) (seconds - tdays * SECSPERDAY); 1593 } 1594 /* 1595 ** Given the range, we can now fearlessly cast... 1596 */ 1597 idays = (int) tdays; 1598 rem += offset - corr; 1599 while (rem < 0) { 1600 rem += SECSPERDAY; 1601 --idays; 1602 } 1603 while (rem >= SECSPERDAY) { 1604 rem -= SECSPERDAY; 1605 ++idays; 1606 } 1607 while (idays < 0) { 1608 if (increment_overflow(&y, -1)) { 1609 errno = EOVERFLOW; 1610 return NULL; 1611 } 1612 idays += year_lengths[isleap(y)]; 1613 } 1614 while (idays >= year_lengths[isleap(y)]) { 1615 idays -= year_lengths[isleap(y)]; 1616 if (increment_overflow(&y, 1)) { 1617 errno = EOVERFLOW; 1618 return NULL; 1619 } 1620 } 1621 tmp->tm_year = y; 1622 if (increment_overflow(&tmp->tm_year, -TM_YEAR_BASE)) { 1623 errno = EOVERFLOW; 1624 return NULL; 1625 } 1626 tmp->tm_yday = idays; 1627 /* 1628 ** The "extra" mods below avoid overflow problems. 1629 */ 1630 tmp->tm_wday = EPOCH_WDAY + 1631 ((y - EPOCH_YEAR) % DAYSPERWEEK) * 1632 (DAYSPERNYEAR % DAYSPERWEEK) + 1633 leaps_thru_end_of(y - 1) - 1634 leaps_thru_end_of(EPOCH_YEAR - 1) + 1635 idays; 1636 tmp->tm_wday %= DAYSPERWEEK; 1637 if (tmp->tm_wday < 0) 1638 tmp->tm_wday += DAYSPERWEEK; 1639 tmp->tm_hour = (int) (rem / SECSPERHOUR); 1640 rem %= SECSPERHOUR; 1641 tmp->tm_min = (int) (rem / SECSPERMIN); 1642 /* 1643 ** A positive leap second requires a special 1644 ** representation. This uses "... ??:59:60" et seq. 1645 */ 1646 tmp->tm_sec = (int) (rem % SECSPERMIN) + hit; 1647 ip = mon_lengths[isleap(y)]; 1648 for (tmp->tm_mon = 0; idays >= ip[tmp->tm_mon]; ++(tmp->tm_mon)) 1649 idays -= ip[tmp->tm_mon]; 1650 tmp->tm_mday = (int) (idays + 1); 1651 tmp->tm_isdst = 0; 1652 #ifdef TM_GMTOFF 1653 tmp->TM_GMTOFF = offset; 1654 #endif /* defined TM_GMTOFF */ 1655 return tmp; 1656 } 1657 1658 char * 1659 ctime(const time_t *const timep) 1660 { 1661 /* 1662 ** Section 4.12.3.2 of X3.159-1989 requires that 1663 ** The ctime function converts the calendar time pointed to by timer 1664 ** to local time in the form of a string. It is equivalent to 1665 ** asctime(localtime(timer)) 1666 */ 1667 struct tm *rtm = localtime(timep); 1668 if (rtm == NULL) 1669 return NULL; 1670 return asctime(rtm); 1671 } 1672 1673 char * 1674 ctime_r(const time_t *const timep, char *buf) 1675 { 1676 struct tm mytm, *rtm; 1677 1678 rtm = localtime_r(timep, &mytm); 1679 if (rtm == NULL) 1680 return NULL; 1681 return asctime_r(rtm, buf); 1682 } 1683 1684 char * 1685 ctime_rz(const timezone_t sp, const time_t * timep, char *buf) 1686 { 1687 struct tm mytm, *rtm; 1688 1689 rtm = localtime_rz(sp, timep, &mytm); 1690 if (rtm == NULL) 1691 return NULL; 1692 return asctime_r(rtm, buf); 1693 } 1694 1695 /* 1696 ** Adapted from code provided by Robert Elz, who writes: 1697 ** The "best" way to do mktime I think is based on an idea of Bob 1698 ** Kridle's (so its said...) from a long time ago. 1699 ** It does a binary search of the time_t space. Since time_t's are 1700 ** just 32 bits, its a max of 32 iterations (even at 64 bits it 1701 ** would still be very reasonable). 1702 */ 1703 1704 #ifndef WRONG 1705 #define WRONG (-1) 1706 #endif /* !defined WRONG */ 1707 1708 /* 1709 ** Simplified normalize logic courtesy Paul Eggert. 1710 */ 1711 1712 static int 1713 increment_overflow(int *number, int delta) 1714 { 1715 int number0; 1716 1717 number0 = *number; 1718 *number += delta; 1719 return (*number < number0) != (delta < 0); 1720 } 1721 1722 static int 1723 long_increment_overflow(long *number, int delta) 1724 { 1725 long number0; 1726 1727 number0 = *number; 1728 *number += delta; 1729 return (*number < number0) != (delta < 0); 1730 } 1731 1732 static int 1733 normalize_overflow(int *const tensptr, int *const unitsptr, const int base) 1734 { 1735 int tensdelta; 1736 1737 tensdelta = (*unitsptr >= 0) ? 1738 (*unitsptr / base) : 1739 (-1 - (-1 - *unitsptr) / base); 1740 *unitsptr -= tensdelta * base; 1741 return increment_overflow(tensptr, tensdelta); 1742 } 1743 1744 static int 1745 long_normalize_overflow(long *const tensptr, int *const unitsptr, 1746 const int base) 1747 { 1748 int tensdelta; 1749 1750 tensdelta = (*unitsptr >= 0) ? 1751 (*unitsptr / base) : 1752 (-1 - (-1 - *unitsptr) / base); 1753 *unitsptr -= tensdelta * base; 1754 return long_increment_overflow(tensptr, tensdelta); 1755 } 1756 1757 static int 1758 tmcomp(const struct tm *const atmp, const struct tm *const btmp) 1759 { 1760 int result; 1761 1762 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 && 1763 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 && 1764 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && 1765 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && 1766 (result = (atmp->tm_min - btmp->tm_min)) == 0) 1767 result = atmp->tm_sec - btmp->tm_sec; 1768 return result; 1769 } 1770 1771 static time_t 1772 time2sub(const timezone_t sp, struct tm *const tmp, subfun_t funcp, 1773 const long offset, int *const okayp, const int do_norm_secs) 1774 { 1775 int dir; 1776 int i, j; 1777 int saved_seconds; 1778 long li; 1779 time_t lo; 1780 time_t hi; 1781 long y; 1782 time_t newt; 1783 time_t t; 1784 struct tm yourtm, mytm; 1785 1786 *okayp = FALSE; 1787 yourtm = *tmp; 1788 if (do_norm_secs) { 1789 if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec, 1790 SECSPERMIN)) 1791 return WRONG; 1792 } 1793 if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) 1794 return WRONG; 1795 if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) 1796 return WRONG; 1797 y = yourtm.tm_year; 1798 if (long_normalize_overflow(&y, &yourtm.tm_mon, MONSPERYEAR)) 1799 return WRONG; 1800 /* 1801 ** Turn y into an actual year number for now. 1802 ** It is converted back to an offset from TM_YEAR_BASE later. 1803 */ 1804 if (long_increment_overflow(&y, TM_YEAR_BASE)) 1805 return WRONG; 1806 while (yourtm.tm_mday <= 0) { 1807 if (long_increment_overflow(&y, -1)) 1808 return WRONG; 1809 li = y + (1 < yourtm.tm_mon); 1810 yourtm.tm_mday += year_lengths[isleap(li)]; 1811 } 1812 while (yourtm.tm_mday > DAYSPERLYEAR) { 1813 li = y + (1 < yourtm.tm_mon); 1814 yourtm.tm_mday -= year_lengths[isleap(li)]; 1815 if (long_increment_overflow(&y, 1)) 1816 return WRONG; 1817 } 1818 for ( ; ; ) { 1819 i = mon_lengths[isleap(y)][yourtm.tm_mon]; 1820 if (yourtm.tm_mday <= i) 1821 break; 1822 yourtm.tm_mday -= i; 1823 if (++yourtm.tm_mon >= MONSPERYEAR) { 1824 yourtm.tm_mon = 0; 1825 if (long_increment_overflow(&y, 1)) 1826 return WRONG; 1827 } 1828 } 1829 if (long_increment_overflow(&y, -TM_YEAR_BASE)) 1830 return WRONG; 1831 yourtm.tm_year = y; 1832 if (yourtm.tm_year != y) 1833 return WRONG; 1834 if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN) 1835 saved_seconds = 0; 1836 else if (y + TM_YEAR_BASE < EPOCH_YEAR) { 1837 /* 1838 ** We can't set tm_sec to 0, because that might push the 1839 ** time below the minimum representable time. 1840 ** Set tm_sec to 59 instead. 1841 ** This assumes that the minimum representable time is 1842 ** not in the same minute that a leap second was deleted from, 1843 ** which is a safer assumption than using 58 would be. 1844 */ 1845 if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) 1846 return WRONG; 1847 saved_seconds = yourtm.tm_sec; 1848 yourtm.tm_sec = SECSPERMIN - 1; 1849 } else { 1850 saved_seconds = yourtm.tm_sec; 1851 yourtm.tm_sec = 0; 1852 } 1853 /* 1854 ** Do a binary search (this works whatever time_t's type is). 1855 */ 1856 /* LINTED constant */ 1857 if (!TYPE_SIGNED(time_t)) { 1858 lo = 0; 1859 hi = lo - 1; 1860 /* LINTED constant */ 1861 } else if (!TYPE_INTEGRAL(time_t)) { 1862 /* CONSTCOND */ 1863 if (sizeof(time_t) > sizeof(float)) 1864 /* LINTED assumed double */ 1865 hi = (time_t) DBL_MAX; 1866 /* LINTED assumed float */ 1867 else hi = (time_t) FLT_MAX; 1868 lo = -hi; 1869 } else { 1870 lo = 1; 1871 for (i = 0; i < (int) TYPE_BIT(time_t) - 1; ++i) 1872 lo *= 2; 1873 hi = -(lo + 1); 1874 } 1875 for ( ; ; ) { 1876 t = lo / 2 + hi / 2; 1877 if (t < lo) 1878 t = lo; 1879 else if (t > hi) 1880 t = hi; 1881 if ((*funcp)(sp, &t, offset, &mytm) == NULL) { 1882 /* 1883 ** Assume that t is too extreme to be represented in 1884 ** a struct tm; arrange things so that it is less 1885 ** extreme on the next pass. 1886 */ 1887 dir = (t > 0) ? 1 : -1; 1888 } else dir = tmcomp(&mytm, &yourtm); 1889 if (dir != 0) { 1890 if (t == lo) { 1891 ++t; 1892 if (t <= lo) 1893 return WRONG; 1894 ++lo; 1895 } else if (t == hi) { 1896 --t; 1897 if (t >= hi) 1898 return WRONG; 1899 --hi; 1900 } 1901 if (lo > hi) 1902 return WRONG; 1903 if (dir > 0) 1904 hi = t; 1905 else lo = t; 1906 continue; 1907 } 1908 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) 1909 break; 1910 /* 1911 ** Right time, wrong type. 1912 ** Hunt for right time, right type. 1913 ** It's okay to guess wrong since the guess 1914 ** gets checked. 1915 */ 1916 if (sp == NULL) 1917 return WRONG; 1918 for (i = sp->typecnt - 1; i >= 0; --i) { 1919 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) 1920 continue; 1921 for (j = sp->typecnt - 1; j >= 0; --j) { 1922 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) 1923 continue; 1924 newt = t + sp->ttis[j].tt_gmtoff - 1925 sp->ttis[i].tt_gmtoff; 1926 if ((*funcp)(sp, &newt, offset, &mytm) == NULL) 1927 continue; 1928 if (tmcomp(&mytm, &yourtm) != 0) 1929 continue; 1930 if (mytm.tm_isdst != yourtm.tm_isdst) 1931 continue; 1932 /* 1933 ** We have a match. 1934 */ 1935 t = newt; 1936 goto label; 1937 } 1938 } 1939 return WRONG; 1940 } 1941 label: 1942 newt = t + saved_seconds; 1943 if ((newt < t) != (saved_seconds < 0)) 1944 return WRONG; 1945 t = newt; 1946 if ((*funcp)(sp, &t, offset, tmp)) 1947 *okayp = TRUE; 1948 return t; 1949 } 1950 1951 static time_t 1952 time2(const timezone_t sp, struct tm *const tmp, subfun_t funcp, 1953 const long offset, int *const okayp) 1954 { 1955 time_t t; 1956 1957 /* 1958 ** First try without normalization of seconds 1959 ** (in case tm_sec contains a value associated with a leap second). 1960 ** If that fails, try with normalization of seconds. 1961 */ 1962 t = time2sub(sp, tmp, funcp, offset, okayp, FALSE); 1963 return *okayp ? t : time2sub(sp, tmp, funcp, offset, okayp, TRUE); 1964 } 1965 1966 static time_t 1967 time1(const timezone_t sp, struct tm *const tmp, subfun_t funcp, 1968 long offset) 1969 { 1970 time_t t; 1971 int samei, otheri; 1972 int sameind, otherind; 1973 int i; 1974 int nseen; 1975 int seen[TZ_MAX_TYPES]; 1976 int types[TZ_MAX_TYPES]; 1977 int okay; 1978 1979 if (tmp->tm_isdst > 1) 1980 tmp->tm_isdst = 1; 1981 t = time2(sp, tmp, funcp, offset, &okay); 1982 #ifdef PCTS 1983 /* 1984 ** PCTS code courtesy Grant Sullivan. 1985 */ 1986 if (okay) 1987 return t; 1988 if (tmp->tm_isdst < 0) 1989 tmp->tm_isdst = 0; /* reset to std and try again */ 1990 #endif /* defined PCTS */ 1991 #ifndef PCTS 1992 if (okay || tmp->tm_isdst < 0) 1993 return t; 1994 #endif /* !defined PCTS */ 1995 /* 1996 ** We're supposed to assume that somebody took a time of one type 1997 ** and did some math on it that yielded a "struct tm" that's bad. 1998 ** We try to divine the type they started from and adjust to the 1999 ** type they need. 2000 */ 2001 if (sp == NULL) 2002 return WRONG; 2003 for (i = 0; i < sp->typecnt; ++i) 2004 seen[i] = FALSE; 2005 nseen = 0; 2006 for (i = sp->timecnt - 1; i >= 0; --i) 2007 if (!seen[sp->types[i]]) { 2008 seen[sp->types[i]] = TRUE; 2009 types[nseen++] = sp->types[i]; 2010 } 2011 for (sameind = 0; sameind < nseen; ++sameind) { 2012 samei = types[sameind]; 2013 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) 2014 continue; 2015 for (otherind = 0; otherind < nseen; ++otherind) { 2016 otheri = types[otherind]; 2017 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) 2018 continue; 2019 tmp->tm_sec += (int)(sp->ttis[otheri].tt_gmtoff - 2020 sp->ttis[samei].tt_gmtoff); 2021 tmp->tm_isdst = !tmp->tm_isdst; 2022 t = time2(sp, tmp, funcp, offset, &okay); 2023 if (okay) 2024 return t; 2025 tmp->tm_sec -= (int)(sp->ttis[otheri].tt_gmtoff - 2026 sp->ttis[samei].tt_gmtoff); 2027 tmp->tm_isdst = !tmp->tm_isdst; 2028 } 2029 } 2030 return WRONG; 2031 } 2032 2033 time_t 2034 mktime_z(const timezone_t sp, struct tm *tmp) 2035 { 2036 if (sp == NULL) 2037 return time1(NULL, tmp, gmtsub, 0L); 2038 else 2039 return time1(sp, tmp, localsub, 0L); 2040 } 2041 2042 time_t 2043 mktime(struct tm * const tmp) 2044 { 2045 time_t result; 2046 2047 rwlock_wrlock(&lcl_lock); 2048 tzset_unlocked(); 2049 result = mktime_z(lclptr, tmp); 2050 rwlock_unlock(&lcl_lock); 2051 return result; 2052 } 2053 2054 #ifdef STD_INSPIRED 2055 2056 time_t 2057 timelocal_z(const timezone_t sp, struct tm *tmp) 2058 { 2059 if (tmp != NULL) 2060 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 2061 return mktime_z(sp, tmp); 2062 } 2063 2064 time_t 2065 timelocal(struct tm *const tmp) 2066 { 2067 tmp->tm_isdst = -1; /* in case it wasn't initialized */ 2068 return mktime(tmp); 2069 } 2070 2071 time_t 2072 timegm(struct tm *const tmp) 2073 { 2074 tmp->tm_isdst = 0; 2075 return time1(gmtptr, tmp, gmtsub, 0L); 2076 } 2077 2078 time_t 2079 timeoff(struct tm *const tmp, const long offset) 2080 { 2081 tmp->tm_isdst = 0; 2082 return time1(gmtptr, tmp, gmtsub, offset); 2083 } 2084 2085 #endif /* defined STD_INSPIRED */ 2086 2087 #ifdef CMUCS 2088 2089 /* 2090 ** The following is supplied for compatibility with 2091 ** previous versions of the CMUCS runtime library. 2092 */ 2093 2094 long 2095 gtime(struct tm *const tmp) 2096 { 2097 const time_t t = mktime(tmp); 2098 2099 if (t == WRONG) 2100 return -1; 2101 return t; 2102 } 2103 2104 #endif /* defined CMUCS */ 2105 2106 /* 2107 ** XXX--is the below the right way to conditionalize?? 2108 */ 2109 2110 #ifdef STD_INSPIRED 2111 2112 /* 2113 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 2114 ** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which 2115 ** is not the case if we are accounting for leap seconds. 2116 ** So, we provide the following conversion routines for use 2117 ** when exchanging timestamps with POSIX conforming systems. 2118 */ 2119 2120 static long 2121 leapcorr(const timezone_t sp, time_t *timep) 2122 { 2123 struct lsinfo * lp; 2124 int i; 2125 2126 i = sp->leapcnt; 2127 while (--i >= 0) { 2128 lp = &sp->lsis[i]; 2129 if (*timep >= lp->ls_trans) 2130 return lp->ls_corr; 2131 } 2132 return 0; 2133 } 2134 2135 time_t 2136 time2posix_z(const timezone_t sp, time_t t) 2137 { 2138 return t - leapcorr(sp, &t); 2139 } 2140 2141 time_t 2142 time2posix(time_t t) 2143 { 2144 time_t result; 2145 rwlock_wrlock(&lcl_lock); 2146 tzset_unlocked(); 2147 result = t - leapcorr(lclptr, &t); 2148 rwlock_unlock(&lcl_lock); 2149 return (result); 2150 } 2151 2152 time_t 2153 posix2time_z(const timezone_t sp, time_t t) 2154 { 2155 time_t x; 2156 time_t y; 2157 2158 /* 2159 ** For a positive leap second hit, the result 2160 ** is not unique. For a negative leap second 2161 ** hit, the corresponding time doesn't exist, 2162 ** so we return an adjacent second. 2163 */ 2164 x = t + leapcorr(sp, &t); 2165 y = x - leapcorr(sp, &x); 2166 if (y < t) { 2167 do { 2168 x++; 2169 y = x - leapcorr(sp, &x); 2170 } while (y < t); 2171 if (t != y) { 2172 return x - 1; 2173 } 2174 } else if (y > t) { 2175 do { 2176 --x; 2177 y = x - leapcorr(sp, &x); 2178 } while (y > t); 2179 if (t != y) { 2180 return x + 1; 2181 } 2182 } 2183 return x; 2184 } 2185 2186 2187 2188 time_t 2189 posix2time(time_t t) 2190 { 2191 time_t result; 2192 2193 rwlock_wrlock(&lcl_lock); 2194 tzset_unlocked(); 2195 result = posix2time_z(lclptr, t); 2196 rwlock_unlock(&lcl_lock); 2197 return result; 2198 } 2199 2200 #endif /* defined STD_INSPIRED */ 2201
Indexes created Thu Oct 02 10:09:58 GMT 2025