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