1 /* 2 * @(#)zdump.c 8.6 3 * $FreeBSD: src/usr.sbin/zic/zdump.c,v 1.7 1999/08/28 01:21:19 peter Exp $ 4 * $DragonFly: src/usr.sbin/zic/zdump.c,v 1.5 2008/10/19 20:15:58 swildner Exp $ 5 */ 6 /* 7 ** This code has been made independent of the rest of the time 8 ** conversion package to increase confidence in the verification it provides. 9 ** You can use this code to help in verifying other implementations. 10 */ 11 12 #include <ctype.h> /* for isalpha et al. */ 13 #include <err.h> 14 #include <float.h> /* for FLT_MAX and DBL_MAX */ 15 #include <stdio.h> /* for stdout, stderr */ 16 #include <stdlib.h> /* for exit, malloc, atoi */ 17 #include <string.h> /* for strcpy */ 18 #include <sys/types.h> /* for time_t */ 19 #include <time.h> /* for struct tm */ 20 #include <unistd.h> 21 22 #ifndef ZDUMP_LO_YEAR 23 #define ZDUMP_LO_YEAR (-500) 24 #endif /* !defined ZDUMP_LO_YEAR */ 25 26 #ifndef ZDUMP_HI_YEAR 27 #define ZDUMP_HI_YEAR 2500 28 #endif /* !defined ZDUMP_HI_YEAR */ 29 30 #ifndef MAX_STRING_LENGTH 31 #define MAX_STRING_LENGTH 1024 32 #endif /* !defined MAX_STRING_LENGTH */ 33 34 #ifndef TRUE 35 #define TRUE 1 36 #endif /* !defined TRUE */ 37 38 #ifndef FALSE 39 #define FALSE 0 40 #endif /* !defined FALSE */ 41 42 #ifndef EXIT_SUCCESS 43 #define EXIT_SUCCESS 0 44 #endif /* !defined EXIT_SUCCESS */ 45 46 #ifndef EXIT_FAILURE 47 #define EXIT_FAILURE 1 48 #endif /* !defined EXIT_FAILURE */ 49 50 #ifndef SECSPERMIN 51 #define SECSPERMIN 60 52 #endif /* !defined SECSPERMIN */ 53 54 #ifndef MINSPERHOUR 55 #define MINSPERHOUR 60 56 #endif /* !defined MINSPERHOUR */ 57 58 #ifndef SECSPERHOUR 59 #define SECSPERHOUR (SECSPERMIN * MINSPERHOUR) 60 #endif /* !defined SECSPERHOUR */ 61 62 #ifndef HOURSPERDAY 63 #define HOURSPERDAY 24 64 #endif /* !defined HOURSPERDAY */ 65 66 #ifndef EPOCH_YEAR 67 #define EPOCH_YEAR 1970 68 #endif /* !defined EPOCH_YEAR */ 69 70 #ifndef TM_YEAR_BASE 71 #define TM_YEAR_BASE 1900 72 #endif /* !defined TM_YEAR_BASE */ 73 74 #ifndef DAYSPERNYEAR 75 #define DAYSPERNYEAR 365 76 #endif /* !defined DAYSPERNYEAR */ 77 78 #ifndef isleap 79 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0)) 80 #endif /* !defined isleap */ 81 82 #ifndef isleap_sum 83 /* 84 ** See tzfile.h for details on isleap_sum. 85 */ 86 #define isleap_sum(a, b) isleap((a) % 400 + (b) % 400) 87 #endif /* !defined isleap_sum */ 88 89 #define SECSPERDAY ((long) SECSPERHOUR * HOURSPERDAY) 90 #define SECSPERNYEAR (SECSPERDAY * DAYSPERNYEAR) 91 #define SECSPERLYEAR (SECSPERNYEAR + SECSPERDAY) 92 93 #ifndef GNUC_or_lint 94 #ifdef lint 95 #define GNUC_or_lint 96 #else /* !defined lint */ 97 #ifdef __GNUC__ 98 #define GNUC_or_lint 99 #endif /* defined __GNUC__ */ 100 #endif /* !defined lint */ 101 #endif /* !defined GNUC_or_lint */ 102 103 #ifndef INITIALIZE 104 #ifdef GNUC_or_lint 105 #define INITIALIZE(x) ((x) = 0) 106 #else /* !defined GNUC_or_lint */ 107 #define INITIALIZE(x) 108 #endif /* !defined GNUC_or_lint */ 109 #endif /* !defined INITIALIZE */ 110 111 /* 112 ** For the benefit of GNU folk... 113 ** `_(MSGID)' uses the current locale's message library string for MSGID. 114 ** The default is to use gettext if available, and use MSGID otherwise. 115 */ 116 117 #ifndef _ 118 #define _(msgid) msgid 119 #endif /* !defined _ */ 120 121 #ifndef TZ_DOMAIN 122 #define TZ_DOMAIN "tz" 123 #endif /* !defined TZ_DOMAIN */ 124 125 extern char ** environ; 126 extern char * tzname[2]; 127 128 static time_t absolute_min_time; 129 static time_t absolute_max_time; 130 static size_t longest; 131 static int warned; 132 133 static char *abbr(struct tm *tmp); 134 static void abbrok(const char *abbrp, const char *zone); 135 static long delta(struct tm *newp, struct tm *oldp); 136 static void dumptime(const struct tm *tmp); 137 static time_t hunt(char *name, time_t lot, time_t hit); 138 static void setabsolutes(void); 139 static void show(char *zone, time_t t, int v); 140 static const char *tformat(void); 141 static time_t yeartot(long y); 142 static void usage(void); 143 144 #ifndef TYPECHECK 145 #define my_localtime localtime 146 #else /* !defined TYPECHECK */ 147 static struct tm * 148 my_localtime(time_t *tp) 149 { 150 struct tm * tmp; 151 152 tmp = localtime(tp); 153 if (tp != NULL && tmp != NULL) { 154 struct tm tm; 155 time_t t; 156 157 tm = *tmp; 158 t = mktime(&tm); 159 if (t - *tp >= 1 || *tp - t >= 1) { 160 fflush(stdout); 161 fprintf(stderr, "\n%s: ", progname); 162 fprintf(stderr, tformat(), *tp); 163 fprintf(stderr, " ->"); 164 fprintf(stderr, " year=%d", tmp->tm_year); 165 fprintf(stderr, " mon=%d", tmp->tm_mon); 166 fprintf(stderr, " mday=%d", tmp->tm_mday); 167 fprintf(stderr, " hour=%d", tmp->tm_hour); 168 fprintf(stderr, " min=%d", tmp->tm_min); 169 fprintf(stderr, " sec=%d", tmp->tm_sec); 170 fprintf(stderr, " isdst=%d", tmp->tm_isdst); 171 fprintf(stderr, " -> "); 172 fprintf(stderr, tformat(), t); 173 fprintf(stderr, "\n"); 174 } 175 } 176 return tmp; 177 } 178 #endif /* !defined TYPECHECK */ 179 180 static void 181 abbrok(const char * const abbrp, const char * const zone) 182 { 183 const char *cp; 184 char *wp; 185 186 if (warned) 187 return; 188 cp = abbrp; 189 wp = NULL; 190 while (isascii((unsigned char) *cp) && isalpha((unsigned char) *cp)) 191 ++cp; 192 if (cp - abbrp == 0) 193 wp = _("lacks alphabetic at start"); 194 else if (cp - abbrp < 3) 195 wp = _("has fewer than 3 alphabetics"); 196 else if (cp - abbrp > 6) 197 wp = _("has more than 6 alphabetics"); 198 if (wp == NULL && (*cp == '+' || *cp == '-')) { 199 ++cp; 200 if (isascii((unsigned char) *cp) && 201 isdigit((unsigned char) *cp)) 202 if (*cp++ == '1' && *cp >= '0' && *cp <= '4') 203 ++cp; 204 if (*cp != '\0') 205 wp = _("differs from POSIX standard"); 206 } 207 if (wp == NULL) 208 return; 209 fflush(stdout); 210 warnx(_("warning: zone \"%s\" abbreviation \"%s\" %s\n"), 211 zone, abbrp, wp); 212 warned = TRUE; 213 } 214 215 int 216 main(int argc, char *argv[]) 217 { 218 int i; 219 int c; 220 int vflag; 221 char *cutarg; 222 long cutloyear = ZDUMP_LO_YEAR; 223 long cuthiyear = ZDUMP_HI_YEAR; 224 time_t cutlotime; 225 time_t cuthitime; 226 char **fakeenv; 227 time_t now; 228 time_t t; 229 time_t newt; 230 struct tm tm; 231 struct tm newtm; 232 struct tm *tmp; 233 struct tm *newtmp; 234 235 INITIALIZE(cutlotime); 236 INITIALIZE(cuthitime); 237 vflag = 0; 238 cutarg = NULL; 239 while ((c = getopt(argc, argv, "c:v")) == 'c' || c == 'v') 240 if (c == 'v') 241 vflag = 1; 242 else cutarg = optarg; 243 if ((c != EOF && c != -1) || 244 (optind == argc - 1 && strcmp(argv[optind], "=") == 0)) { 245 usage(); 246 } 247 if (vflag) { 248 if (cutarg != NULL) { 249 long lo; 250 long hi; 251 char dummy; 252 253 if (sscanf(cutarg, "%ld%c", &hi, &dummy) == 1) { 254 cuthiyear = hi; 255 } else if (sscanf(cutarg, "%ld,%ld%c", 256 &lo, &hi, &dummy) == 2) { 257 cutloyear = lo; 258 cuthiyear = hi; 259 } else { 260 errx(EXIT_FAILURE, 261 _("%s: wild -c argument %s\n"), 262 cutarg); 263 } 264 } 265 setabsolutes(); 266 cutlotime = yeartot(cutloyear); 267 cuthitime = yeartot(cuthiyear); 268 } 269 time(&now); 270 longest = 0; 271 for (i = optind; i < argc; ++i) 272 if (strlen(argv[i]) > longest) 273 longest = strlen(argv[i]); 274 { 275 int from; 276 int to; 277 278 for (i = 0; environ[i] != NULL; ++i) 279 continue; 280 fakeenv = (char **) malloc((size_t) ((i + 2) * 281 sizeof *fakeenv)); 282 if (fakeenv == NULL || 283 (fakeenv[0] = (char *) malloc((size_t) (longest + 284 4))) == NULL) 285 errx(EXIT_FAILURE, 286 _("malloc() failed")); 287 to = 0; 288 strcpy(fakeenv[to++], "TZ="); 289 for (from = 0; environ[from] != NULL; ++from) 290 if (strncmp(environ[from], "TZ=", 3) != 0) 291 fakeenv[to++] = environ[from]; 292 fakeenv[to] = NULL; 293 environ = fakeenv; 294 } 295 for (i = optind; i < argc; ++i) { 296 static char buf[MAX_STRING_LENGTH]; 297 298 strcpy(&fakeenv[0][3], argv[i]); 299 if (!vflag) { 300 show(argv[i], now, FALSE); 301 continue; 302 } 303 warned = FALSE; 304 t = absolute_min_time; 305 show(argv[i], t, TRUE); 306 t += SECSPERHOUR * HOURSPERDAY; 307 show(argv[i], t, TRUE); 308 if (t < cutlotime) 309 t = cutlotime; 310 tmp = my_localtime(&t); 311 if (tmp != NULL) { 312 tm = *tmp; 313 strncpy(buf, abbr(&tm), (sizeof buf) - 1); 314 } 315 for ( ; ; ) { 316 if (t >= cuthitime) 317 break; 318 newt = t + SECSPERHOUR * 12; 319 if (newt >= cuthitime) 320 break; 321 if (newt <= t) 322 break; 323 newtmp = localtime(&newt); 324 if (newtmp != NULL) 325 newtm = *newtmp; 326 if ((tmp == NULL || newtmp == NULL) ? (tmp != newtmp) : 327 (delta(&newtm, &tm) != (newt - t) || 328 newtm.tm_isdst != tm.tm_isdst || 329 strcmp(abbr(&newtm), buf) != 0)) { 330 newt = hunt(argv[i], t, newt); 331 newtmp = localtime(&newt); 332 if (newtmp != NULL) { 333 newtm = *newtmp; 334 strncpy(buf, 335 abbr(&newtm), 336 (sizeof buf) - 1); 337 } 338 } 339 t = newt; 340 tm = newtm; 341 tmp = newtmp; 342 } 343 t = absolute_max_time; 344 t -= SECSPERHOUR * HOURSPERDAY; 345 show(argv[i], t, TRUE); 346 t += SECSPERHOUR * HOURSPERDAY; 347 show(argv[i], t, TRUE); 348 } 349 if (fflush(stdout) || ferror(stdout)) 350 errx(EXIT_FAILURE, _("error writing standard output")); 351 exit(EXIT_SUCCESS); 352 /* If exit fails to exit... */ 353 return EXIT_FAILURE; 354 } 355 356 static void 357 setabsolutes(void) 358 { 359 if (0.5 == (time_t) 0.5) { 360 /* 361 ** time_t is floating. 362 */ 363 if (sizeof (time_t) == sizeof (float)) { 364 absolute_min_time = (time_t) -FLT_MAX; 365 absolute_max_time = (time_t) FLT_MAX; 366 } else if (sizeof (time_t) == sizeof (double)) { 367 absolute_min_time = (time_t) -DBL_MAX; 368 absolute_max_time = (time_t) DBL_MAX; 369 } else { 370 errx(EXIT_FAILURE, 371 _("use of -v on system with floating time_t other than float or double\n")); 372 } 373 } else if (0 > (time_t) -1) { 374 /* 375 ** time_t is signed. Assume overflow wraps around. 376 */ 377 time_t t = 0; 378 time_t t1 = 1; 379 380 while (t < t1) { 381 t = t1; 382 t1 = 2 * t1 + 1; 383 } 384 385 absolute_max_time = t; 386 t = -t; 387 absolute_min_time = t - 1; 388 if (t < absolute_min_time) 389 absolute_min_time = t; 390 } else { 391 /* 392 ** time_t is unsigned. 393 */ 394 absolute_min_time = 0; 395 absolute_max_time = absolute_min_time - 1; 396 } 397 } 398 399 static void 400 usage(void) 401 { 402 fprintf(stderr, _("usage: zdump [-v] [-c cutoff] zonename ...\n")); 403 exit(EXIT_FAILURE); 404 } 405 406 static time_t 407 yeartot(const long y) 408 { 409 long myy; 410 long seconds; 411 time_t t; 412 413 myy = EPOCH_YEAR; 414 t = 0; 415 while (myy != y) { 416 if (myy < y) { 417 seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR; 418 ++myy; 419 if (t > absolute_max_time - seconds) { 420 t = absolute_max_time; 421 break; 422 } 423 t += seconds; 424 } else { 425 --myy; 426 seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR; 427 if (t < absolute_min_time + seconds) { 428 t = absolute_min_time; 429 break; 430 } 431 t -= seconds; 432 } 433 } 434 return t; 435 } 436 437 static time_t 438 hunt(char *name, time_t lot, time_t hit) 439 { 440 time_t t; 441 long diff; 442 struct tm lotm; 443 struct tm * lotmp; 444 struct tm tm; 445 struct tm * tmp; 446 char loab[MAX_STRING_LENGTH]; 447 448 lotmp = my_localtime(&lot); 449 if (lotmp != NULL) { 450 lotm = *lotmp; 451 strncpy(loab, abbr(&lotm), (sizeof loab) - 1); 452 } 453 for ( ; ; ) { 454 diff = (long) (hit - lot); 455 if (diff < 2) 456 break; 457 t = lot; 458 t += diff / 2; 459 if (t <= lot) 460 ++t; 461 else if (t >= hit) 462 --t; 463 tmp = my_localtime(&t); 464 if (tmp != NULL) 465 tm = *tmp; 466 if ((lotmp == NULL || tmp == NULL) ? (lotmp == tmp) : 467 (delta(&tm, &lotm) == (t - lot) && 468 tm.tm_isdst == lotm.tm_isdst && 469 strcmp(abbr(&tm), loab) == 0)) { 470 lot = t; 471 lotm = tm; 472 lotmp = tmp; 473 } else hit = t; 474 } 475 show(name, lot, TRUE); 476 show(name, hit, TRUE); 477 return hit; 478 } 479 480 /* 481 ** Thanks to Paul Eggert for logic used in delta. 482 */ 483 484 static long 485 delta(struct tm *newp, struct tm *oldp) 486 { 487 long result; 488 int tmy; 489 490 if (newp->tm_year < oldp->tm_year) 491 return -delta(oldp, newp); 492 result = 0; 493 for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy) 494 result += DAYSPERNYEAR + isleap_sum(tmy, TM_YEAR_BASE); 495 result += newp->tm_yday - oldp->tm_yday; 496 result *= HOURSPERDAY; 497 result += newp->tm_hour - oldp->tm_hour; 498 result *= MINSPERHOUR; 499 result += newp->tm_min - oldp->tm_min; 500 result *= SECSPERMIN; 501 result += newp->tm_sec - oldp->tm_sec; 502 return result; 503 } 504 505 static void 506 show(char *zone, time_t t, int v) 507 { 508 struct tm * tmp; 509 510 printf("%-*s ", (int) longest, zone); 511 if (v) { 512 tmp = gmtime(&t); 513 if (tmp == NULL) { 514 printf(tformat(), t); 515 } else { 516 dumptime(tmp); 517 printf(" UTC"); 518 } 519 printf(" = "); 520 } 521 tmp = my_localtime(&t); 522 dumptime(tmp); 523 if (tmp != NULL) { 524 if (*abbr(tmp) != '\0') 525 printf(" %s", abbr(tmp)); 526 if (v) { 527 printf(" isdst=%d", tmp->tm_isdst); 528 #ifdef TM_GMTOFF 529 printf(" gmtoff=%ld", tmp->TM_GMTOFF); 530 #endif /* defined TM_GMTOFF */ 531 } 532 } 533 printf("\n"); 534 if (tmp != NULL && *abbr(tmp) != '\0') 535 abbrok(abbr(tmp), zone); 536 } 537 538 static char * 539 abbr(struct tm *tmp) 540 { 541 char * result; 542 static char nada; 543 544 if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1) 545 return &nada; 546 result = tzname[tmp->tm_isdst]; 547 return (result == NULL) ? &nada : result; 548 } 549 550 /* 551 ** The code below can fail on certain theoretical systems; 552 ** it works on all known real-world systems as of 2004-12-30. 553 */ 554 555 static const char * 556 tformat(void) 557 { 558 if (0.5 == (time_t) 0.5) { /* floating */ 559 if (sizeof (time_t) > sizeof (double)) 560 return "%Lg"; 561 return "%g"; 562 } 563 if (0 > (time_t) -1) { /* signed */ 564 if (sizeof (time_t) > sizeof (long)) 565 return "%lld"; 566 if (sizeof (time_t) > sizeof (int)) 567 return "%ld"; 568 return "%d"; 569 } 570 if (sizeof (time_t) > sizeof (unsigned long)) 571 return "%llu"; 572 if (sizeof (time_t) > sizeof (unsigned int)) 573 return "%lu"; 574 return "%u"; 575 } 576 577 static void 578 dumptime(const struct tm *timeptr) 579 { 580 static const char wday_name[][3] = { 581 "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" 582 }; 583 static const char mon_name[][3] = { 584 "Jan", "Feb", "Mar", "Apr", "May", "Jun", 585 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" 586 }; 587 const char * wn; 588 const char * mn; 589 int lead; 590 int trail; 591 592 if (timeptr == NULL) { 593 printf("NULL"); 594 return; 595 } 596 /* 597 ** The packaged versions of localtime and gmtime never put out-of-range 598 ** values in tm_wday or tm_mon, but since this code might be compiled 599 ** with other (perhaps experimental) versions, paranoia is in order. 600 */ 601 if (timeptr->tm_wday < 0 || timeptr->tm_wday >= 602 (int) (sizeof wday_name / sizeof wday_name[0])) 603 wn = "???"; 604 else wn = wday_name[timeptr->tm_wday]; 605 if (timeptr->tm_mon < 0 || timeptr->tm_mon >= 606 (int) (sizeof mon_name / sizeof mon_name[0])) 607 mn = "???"; 608 else mn = mon_name[timeptr->tm_mon]; 609 printf("%.3s %.3s%3d %.2d:%.2d:%.2d ", 610 wn, mn, 611 timeptr->tm_mday, timeptr->tm_hour, 612 timeptr->tm_min, timeptr->tm_sec); 613 #define DIVISOR 10 614 trail = timeptr->tm_year % DIVISOR + TM_YEAR_BASE % DIVISOR; 615 lead = timeptr->tm_year / DIVISOR + TM_YEAR_BASE / DIVISOR + 616 trail / DIVISOR; 617 trail %= DIVISOR; 618 if (trail < 0 && lead > 0) { 619 trail += DIVISOR; 620 --lead; 621 } else if (lead < 0 && trail > 0) { 622 trail -= DIVISOR; 623 ++lead; 624 } 625 if (lead == 0) 626 printf("%d", trail); 627 else printf("%d%d", lead, ((trail < 0) ? -trail : trail)); 628 } 629