usr.sbin/zic/zdump.c

   1 /*
   2  * $FreeBSD: src/usr.sbin/zic/zdump.c,v 1.7 1999/08/28 01:21:19 peter Exp $
   3  */
   4 /*
   5 ** This code has been made independent of the rest of the time
   6 ** conversion package to increase confidence in the verification it provides.
   7 ** You can use this code to help in verifying other implementations.
   8 */
   9
  10 #include <ctype.h>      /* for isalpha et al. */
  11 #include <err.h>
  12 #include <inttypes.h>
  13 #include <limits.h>     /* for CHAR_BIT, LLONG_MAX */
  14 #include <stdint.h>
  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      ((int_fast32_t) SECSPERHOUR * HOURSPERDAY)
  90 #define SECSPERNYEAR    (SECSPERDAY * DAYSPERNYEAR)
  91 #define SECSPERLYEAR    (SECSPERNYEAR + SECSPERDAY)
  92 #define SECSPER400YEARS (SECSPERNYEAR * (intmax_t) (300 + 3)    \
  93                          + SECSPERLYEAR * (intmax_t) (100 - 3))
  94
  95 /*
  96 ** True if SECSPER400YEARS is known to be representable as an
  97 ** intmax_t.  It's OK that SECSPER400YEARS_FITS can in theory be false
  98 ** even if SECSPER400YEARS is representable, because when that happens
  99 ** the code merely runs a bit more slowly, and this slowness doesn't
 100 ** occur on any practical platform.
 101 */
 102 enum { SECSPER400YEARS_FITS = SECSPERLYEAR <= INTMAX_MAX / 400 };
 103
 104 /*
 105 ** For the benefit of GNU folk...
 106 ** `_(MSGID)' uses the current locale's message library string for MSGID.
 107 ** The default is to use gettext if available, and use MSGID otherwise.
 108 */
 109
 110 #ifndef _
 111 #define _(msgid) msgid
 112 #endif /* !defined _ */
 113
 114 #ifndef TZ_DOMAIN
 115 #define TZ_DOMAIN "tz"
 116 #endif /* !defined TZ_DOMAIN */
 117
 118 extern char **  environ;
 119 extern char *   tzname[2];
 120
 121 /* The minimum and maximum finite time values.  */
 122 static time_t const absolute_min_time =
 123   ((time_t) -1 < 0
 124    ? (time_t) -1 << (CHAR_BIT * sizeof (time_t) - 1)
 125    : 0);
 126 static time_t const absolute_max_time =
 127   ((time_t) -1 < 0
 128    ? - (~ 0 < 0) - ((time_t) -1 << (CHAR_BIT * sizeof (time_t) - 1))
 129    : -1);
 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 intmax_t  delta(struct tm * newp, struct tm * oldp) __pure;
 136 static void      dumptime(const struct tm *tmp);
 137 static time_t    hunt(char *name, time_t lot, time_t hit);
 138 static void      show(char *zone, time_t t, int v);
 139 static const char *tformat(void);
 140 static time_t    yeartot(intmax_t y) __pure;
 141 static void      usage(void);
 142
 143 #ifndef TYPECHECK
 144 #define my_localtime    localtime
 145 #else /* !defined TYPECHECK */
 146 static struct tm *
 147 my_localtime(time_t *tp)
 148 {
 149         struct tm *     tmp;
 150
 151         tmp = localtime(tp);
 152         if (tp != NULL && tmp != NULL) {
 153                 struct tm       tm;
 154                 time_t          t;
 155
 156                 tm = *tmp;
 157                 t = mktime(&tm);
 158                 if (t != *tp) {
 159                         fflush(stdout);
 160                         fprintf(stderr, "\n%s: ", progname);
 161                         fprintf(stderr, tformat(), *tp);
 162                         fprintf(stderr, " ->");
 163                         fprintf(stderr, " year=%d", tmp->tm_year);
 164                         fprintf(stderr, " mon=%d", tmp->tm_mon);
 165                         fprintf(stderr, " mday=%d", tmp->tm_mday);
 166                         fprintf(stderr, " hour=%d", tmp->tm_hour);
 167                         fprintf(stderr, " min=%d", tmp->tm_min);
 168                         fprintf(stderr, " sec=%d", tmp->tm_sec);
 169                         fprintf(stderr, " isdst=%d", tmp->tm_isdst);
 170                         fprintf(stderr, " -> ");
 171                         fprintf(stderr, tformat(), t);
 172                         fprintf(stderr, "\n");
 173                 }
 174         }
 175         return tmp;
 176 }
 177 #endif /* !defined TYPECHECK */
 178
 179 static void
 180 abbrok(const char *const abbrp, const char *const zone)
 181 {
 182         const char *cp;
 183         const char *wp;
 184
 185         if (warned)
 186                 return;
 187         cp = abbrp;
 188         while (isalpha(*cp) || isdigit(*cp) || *cp == '-' || *cp == '+')
 189                 ++cp;
 190         if (cp - abbrp < 3)
 191           wp = _("has fewer than 3 characters");
 192         else if (cp - abbrp > 6)
 193           wp = _("has more than 6 characters");
 194         else if (*cp)
 195           wp = _("has characters other than ASCII alphanumerics, '-' or '+'");
 196         else
 197           return;
 198         fflush(stdout);
 199         warnx(_("warning: zone \"%s\" abbreviation \"%s\" %s\n"),
 200                 zone, abbrp, wp);
 201         warned = TRUE;
 202 }
 203
 204 int
 205 main(int argc, char *argv[])
 206 {
 207         int i;
 208         int vflag;
 209         int Vflag;
 210         char *cutarg;
 211         char *cuttimes;
 212         time_t cutlotime;
 213         time_t cuthitime;
 214         char **fakeenv;
 215         time_t now;
 216         time_t t;
 217         time_t newt;
 218         struct tm tm;
 219         struct tm newtm;
 220         struct tm *tmp;
 221         struct tm *newtmp;
 222
 223         cutlotime = absolute_min_time;
 224         cuthitime = absolute_max_time;
 225         vflag = Vflag = 0;
 226         cutarg = cuttimes = NULL;
 227         for (;;)
 228           switch (getopt(argc, argv, "c:t:vV")) {
 229           case 'c': cutarg = optarg; break;
 230           case 't': cuttimes = optarg; break;
 231           case 'v': vflag = 1; break;
 232           case 'V': Vflag = 1; break;
 233           case -1:
 234             if (! (optind == argc - 1 && strcmp(argv[optind], "=") == 0))
 235               goto arg_processing_done;
 236             /* Fall through.  */
 237           default:
 238             usage();
 239           }
 240  arg_processing_done:;
 241
 242         if (vflag | Vflag) {
 243                 intmax_t        lo;
 244                 intmax_t        hi;
 245                 char *loend, *hiend;
 246                 intmax_t cutloyear = ZDUMP_LO_YEAR;
 247                 intmax_t cuthiyear = ZDUMP_HI_YEAR;
 248                 if (cutarg != NULL) {
 249                         lo = strtoimax(cutarg, &loend, 10);
 250                         if (cutarg != loend && !*loend) {
 251                                 hi = lo;
 252                                 cuthiyear = hi;
 253                         } else if (cutarg != loend && *loend == ','
 254                                    && (hi = strtoimax(loend + 1, &hiend, 10),
 255                                        loend + 1 != hiend && !*hiend)) {
 256                                 cutloyear = lo;
 257                                 cuthiyear = hi;
 258                         } else {
 259                                 errx(EXIT_FAILURE,
 260                                         _("wild -c argument %s\n"),
 261                                         cutarg);
 262                         }
 263                 }
 264                 if (cutarg != NULL || cuttimes == NULL) {
 265                         cutlotime = yeartot(cutloyear);
 266                         cuthitime = yeartot(cuthiyear);
 267                 }
 268                 if (cuttimes != NULL) {
 269                         lo = strtoimax(cuttimes, &loend, 10);
 270                         if (cuttimes != loend && !*loend) {
 271                                 hi = lo;
 272                                 if (hi < cuthitime) {
 273                                         if (hi < absolute_min_time)
 274                                                 hi = absolute_min_time;
 275                                         cuthitime = hi;
 276                                 }
 277                         } else if (cuttimes != loend && *loend == ','
 278                                    && (hi = strtoimax(loend + 1, &hiend, 10),
 279                                        loend + 1 != hiend && !*hiend)) {
 280                                 if (cutlotime < lo) {
 281                                         if (absolute_max_time < lo)
 282                                                 lo = absolute_max_time;
 283                                         cutlotime = lo;
 284                                 }
 285                                 if (hi < cuthitime) {
 286                                         if (hi < absolute_min_time)
 287                                                 hi = absolute_min_time;
 288                                         cuthitime = hi;
 289                                 }
 290                         } else {
 291                                 errx(EXIT_FAILURE,
 292                                         _("wild -t argument %s\n"),
 293                                         cuttimes);
 294                         }
 295                 }
 296         }
 297         time(&now);
 298         longest = 0;
 299         for (i = optind; i < argc; ++i)
 300                 if (strlen(argv[i]) > longest)
 301                         longest = strlen(argv[i]);
 302         {
 303                 int from;
 304                 int to;
 305
 306                 for (i = 0; environ[i] != NULL;  ++i)
 307                         continue;
 308                 fakeenv = malloc((i + 2) * sizeof *fakeenv);
 309                 if (fakeenv == NULL
 310                     || (fakeenv[0] = malloc(longest + 4)) == NULL) {
 311                                         errx(EXIT_FAILURE,
 312                                              _("malloc() failed"));
 313                 }
 314                 to = 0;
 315                 strcpy(fakeenv[to++], "TZ=");
 316                 for (from = 0; environ[from] != NULL; ++from)
 317                         if (strncmp(environ[from], "TZ=", 3) != 0)
 318                                 fakeenv[to++] = environ[from];
 319                 fakeenv[to] = NULL;
 320                 environ = fakeenv;
 321         }
 322         for (i = optind; i < argc; ++i) {
 323                 static char     buf[MAX_STRING_LENGTH];
 324
 325                 strcpy(&fakeenv[0][3], argv[i]);
 326                 if (! (vflag | Vflag)) {
 327                         show(argv[i], now, FALSE);
 328                         continue;
 329                 }
 330                 warned = FALSE;
 331                 t = absolute_min_time;
 332                 if (!Vflag) {
 333                         show(argv[i], t, TRUE);
 334                         t += SECSPERDAY;
 335                         show(argv[i], t, TRUE);
 336                 }
 337                 if (t < cutlotime)
 338                         t = cutlotime;
 339                 tmp = my_localtime(&t);
 340                 if (tmp != NULL) {
 341                         tm = *tmp;
 342                         strncpy(buf, abbr(&tm), (sizeof buf) - 1);
 343                 }
 344                 for ( ; ; ) {
 345                         newt = (t < absolute_max_time - SECSPERDAY / 2
 346                                 ? t + SECSPERDAY / 2
 347                                 : absolute_max_time);
 348                         if (cuthitime <= newt)
 349                                 break;
 350                         newtmp = localtime(&newt);
 351                         if (newtmp != NULL)
 352                                 newtm = *newtmp;
 353                         if ((tmp == NULL || newtmp == NULL) ? (tmp != newtmp) :
 354                                 (delta(&newtm, &tm) != (newt - t) ||
 355                                 newtm.tm_isdst != tm.tm_isdst ||
 356                                 strcmp(abbr(&newtm), buf) != 0)) {
 357                                         newt = hunt(argv[i], t, newt);
 358                                         newtmp = localtime(&newt);
 359                                         if (newtmp != NULL) {
 360                                                 newtm = *newtmp;
 361                                                 strncpy(buf,
 362                                                         abbr(&newtm),
 363                                                         (sizeof buf) - 1);
 364                                         }
 365                         }
 366                         t = newt;
 367                         tm = newtm;
 368                         tmp = newtmp;
 369                 }
 370                 if (!Vflag) {
 371                         t = absolute_max_time;
 372                         t -= SECSPERDAY;
 373                         show(argv[i], t, TRUE);
 374                         t += SECSPERDAY;
 375                         show(argv[i], t, TRUE);
 376                 }
 377         }
 378         if (fflush(stdout) || ferror(stdout))
 379                 errx(EXIT_FAILURE, _("error writing standard output"));
 380         exit(EXIT_SUCCESS);
 381         /* If exit fails to exit... */
 382         return EXIT_FAILURE;
 383 }
 384
 385 static void
 386 usage(void)
 387 {
 388         fprintf(stderr, _("usage: zdump [-vV] [-c [loyear,]hiyear] [-t [lotime,]hitime] zonename ...\n"));
 389         exit(EXIT_FAILURE);
 390 }
 391
 392 static time_t
 393 yeartot(const intmax_t y)
 394 {
 395         intmax_t        myy, seconds, years;
 396         time_t          t;
 397
 398         myy = EPOCH_YEAR;
 399         t = 0;
 400         while (myy < y) {
 401                 if (SECSPER400YEARS_FITS && 400 <= y - myy) {
 402                         intmax_t diff400 = (y - myy) / 400;
 403                         if (INTMAX_MAX / SECSPER400YEARS < diff400)
 404                                 return absolute_max_time;
 405                         seconds = diff400 * SECSPER400YEARS;
 406                         years = diff400 * 400;
 407                 } else {
 408                         seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
 409                         years = 1;
 410                 }
 411                 myy += years;
 412                 if (t > absolute_max_time - seconds)
 413                         return absolute_max_time;
 414                 t += seconds;
 415         }
 416         while (y < myy) {
 417                 if (SECSPER400YEARS_FITS && y + 400 <= myy && myy < 0) {
 418                         intmax_t diff400 = (myy - y) / 400;
 419                         if (INTMAX_MAX / SECSPER400YEARS < diff400)
 420                                 return absolute_min_time;
 421                         seconds = diff400 * SECSPER400YEARS;
 422                         years = diff400 * 400;
 423                 } else {
 424                         seconds = isleap(myy - 1) ? SECSPERLYEAR : SECSPERNYEAR;
 425                         years = 1;
 426                 }
 427                 myy -= years;
 428                 if (t < absolute_min_time + seconds)
 429                         return absolute_min_time;
 430                 t -= seconds;
 431         }
 432         return t;
 433 }
 434
 435 static time_t
 436 hunt(char *name, time_t lot, time_t hit)
 437 {
 438         time_t          t;
 439         struct tm       lotm;
 440         struct tm *     lotmp;
 441         struct tm       tm;
 442         struct tm *     tmp;
 443         char                    loab[MAX_STRING_LENGTH];
 444
 445         lotmp = my_localtime(&lot);
 446         if (lotmp != NULL) {
 447                 lotm = *lotmp;
 448                 strncpy(loab, abbr(&lotm), (sizeof loab) - 1);
 449         }
 450         for ( ; ; ) {
 451                 time_t diff = hit - lot;
 452                 if (diff < 2)
 453                         break;
 454                 t = lot;
 455                 t += diff / 2;
 456                 if (t <= lot)
 457                         ++t;
 458                 else if (t >= hit)
 459                         --t;
 460                 tmp = my_localtime(&t);
 461                 if (tmp != NULL)
 462                         tm = *tmp;
 463                 if ((lotmp == NULL || tmp == NULL) ? (lotmp == tmp) :
 464                         (delta(&tm, &lotm) == (t - lot) &&
 465                         tm.tm_isdst == lotm.tm_isdst &&
 466                         strcmp(abbr(&tm), loab) == 0)) {
 467                                 lot = t;
 468                                 lotm = tm;
 469                                 lotmp = tmp;
 470                 } else  hit = t;
 471         }
 472         show(name, lot, TRUE);
 473         show(name, hit, TRUE);
 474         return hit;
 475 }
 476
 477 /*
 478 ** Thanks to Paul Eggert for logic used in delta.
 479 */
 480
 481 static intmax_t
 482 delta(struct tm *newp, struct tm *oldp)
 483 {
 484         intmax_t        result;
 485         int             tmy;
 486
 487         if (newp->tm_year < oldp->tm_year)
 488                 return -delta(oldp, newp);
 489         result = 0;
 490         for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy)
 491                 result += DAYSPERNYEAR + isleap_sum(tmy, TM_YEAR_BASE);
 492         result += newp->tm_yday - oldp->tm_yday;
 493         result *= HOURSPERDAY;
 494         result += newp->tm_hour - oldp->tm_hour;
 495         result *= MINSPERHOUR;
 496         result += newp->tm_min - oldp->tm_min;
 497         result *= SECSPERMIN;
 498         result += newp->tm_sec - oldp->tm_sec;
 499         return result;
 500 }
 501
 502 static void
 503 show(char *zone, time_t t, int v)
 504 {
 505         struct tm *     tmp;
 506
 507         printf("%-*s  ", (int) longest, zone);
 508         if (v) {
 509                 tmp = gmtime(&t);
 510                 if (tmp == NULL) {
 511                         printf(tformat(), t);
 512                 } else {
 513                         dumptime(tmp);
 514                         printf(" UT");
 515                 }
 516                 printf(" = ");
 517         }
 518         tmp = my_localtime(&t);
 519         dumptime(tmp);
 520         if (tmp != NULL) {
 521                 if (*abbr(tmp) != '\0')
 522                         printf(" %s", abbr(tmp));
 523                 if (v) {
 524                         printf(" isdst=%d", tmp->tm_isdst);
 525                         printf(" gmtoff=%ld", tmp->TM_GMTOFF);
 526                 }
 527         }
 528         printf("\n");
 529         if (tmp != NULL && *abbr(tmp) != '\0')
 530                 abbrok(abbr(tmp), zone);
 531 }
 532
 533 static char *
 534 abbr(struct tm *tmp)
 535 {
 536         char * result;
 537         static char nada;
 538
 539         if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1)
 540                 return &nada;
 541         result = tzname[tmp->tm_isdst];
 542         return (result == NULL) ? &nada : result;
 543 }
 544
 545 /*
 546 ** The code below can fail on certain theoretical systems;
 547 ** it works on all known real-world systems as of 2004-12-30.
 548 */
 549
 550 static const char *
 551 tformat(void)
 552 {
 553         if (0 > (time_t) -1) {          /* signed */
 554                 if (sizeof (time_t) == sizeof (intmax_t))
 555                         return "%"PRIdMAX;
 556                 if (sizeof (time_t) > sizeof (long))
 557                         return "%lld";
 558                 if (sizeof (time_t) > sizeof (int))
 559                         return "%ld";
 560                 return "%d";
 561         }
 562         if (sizeof (time_t) == sizeof (uintmax_t))
 563                 return "%"PRIuMAX;
 564         if (sizeof (time_t) > sizeof (unsigned long))
 565                 return "%llu";
 566         if (sizeof (time_t) > sizeof (unsigned int))
 567                 return "%lu";
 568         return "%u";
 569 }
 570
 571 static void
 572 dumptime(const struct tm *timeptr)
 573 {
 574         static const char       wday_name[][3] = {
 575                 "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
 576         };
 577         static const char       mon_name[][3] = {
 578                 "Jan", "Feb", "Mar", "Apr", "May", "Jun",
 579                 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
 580         };
 581         const char *    wn;
 582         const char *    mn;
 583         int             lead;
 584         int             trail;
 585
 586         if (timeptr == NULL) {
 587                 printf("NULL");
 588                 return;
 589         }
 590         /*
 591         ** The packaged versions of localtime and gmtime never put out-of-range
 592         ** values in tm_wday or tm_mon, but since this code might be compiled
 593         ** with other (perhaps experimental) versions, paranoia is in order.
 594         */
 595         if (timeptr->tm_wday < 0 || timeptr->tm_wday >=
 596                 (int) (sizeof wday_name / sizeof wday_name[0]))
 597                         wn = "???";
 598         else            wn = wday_name[timeptr->tm_wday];
 599         if (timeptr->tm_mon < 0 || timeptr->tm_mon >=
 600                 (int) (sizeof mon_name / sizeof mon_name[0]))
 601                         mn = "???";
 602         else            mn = mon_name[timeptr->tm_mon];
 603         printf("%.3s %.3s%3d %.2d:%.2d:%.2d ",
 604                 wn, mn,
 605                 timeptr->tm_mday, timeptr->tm_hour,
 606                 timeptr->tm_min, timeptr->tm_sec);
 607 #define DIVISOR 10
 608         trail = timeptr->tm_year % DIVISOR + TM_YEAR_BASE % DIVISOR;
 609         lead = timeptr->tm_year / DIVISOR + TM_YEAR_BASE / DIVISOR +
 610                 trail / DIVISOR;
 611         trail %= DIVISOR;
 612         if (trail < 0 && lead > 0) {
 613                 trail += DIVISOR;
 614                 --lead;
 615         } else if (lead < 0 && trail > 0) {
 616                 trail -= DIVISOR;
 617                 ++lead;
 618         }
 619         if (lead == 0)
 620                 printf("%d", trail);
 621         else    printf("%d%d", lead, ((trail < 0) ? -trail : trail));
 622 }