timezone/zdump.c

   1 static char     elsieid[] = "@(#)zdump.c        7.64";
   2
   3 /*
   4 ** This code has been made independent of the rest of the time
   5 ** conversion package to increase confidence in the verification it provides.
   6 ** You can use this code to help in verifying other implementations.
   7 */
   8
   9 #include "stdio.h"      /* for stdout, stderr, perror */
  10 #include "string.h"     /* for strcpy */
  11 #include "sys/types.h"  /* for time_t */
  12 #include "time.h"       /* for struct tm */
  13 #include "stdlib.h"     /* for exit, malloc, atoi */
  14 #include "float.h"      /* for FLT_MAX and DBL_MAX */
  15
  16 #ifndef ZDUMP_LO_YEAR
  17 #define ZDUMP_LO_YEAR   (-500)
  18 #endif /* !defined ZDUMP_LO_YEAR */
  19
  20 #ifndef ZDUMP_HI_YEAR
  21 #define ZDUMP_HI_YEAR   2500
  22 #endif /* !defined ZDUMP_HI_YEAR */
  23
  24 #ifndef MAX_STRING_LENGTH
  25 #define MAX_STRING_LENGTH       1024
  26 #endif /* !defined MAX_STRING_LENGTH */
  27
  28 #ifndef TRUE
  29 #define TRUE            1
  30 #endif /* !defined TRUE */
  31
  32 #ifndef FALSE
  33 #define FALSE           0
  34 #endif /* !defined FALSE */
  35
  36 #ifndef EXIT_SUCCESS
  37 #define EXIT_SUCCESS    0
  38 #endif /* !defined EXIT_SUCCESS */
  39
  40 #ifndef EXIT_FAILURE
  41 #define EXIT_FAILURE    1
  42 #endif /* !defined EXIT_FAILURE */
  43
  44 #ifndef SECSPERMIN
  45 #define SECSPERMIN      60
  46 #endif /* !defined SECSPERMIN */
  47
  48 #ifndef MINSPERHOUR
  49 #define MINSPERHOUR     60
  50 #endif /* !defined MINSPERHOUR */
  51
  52 #ifndef SECSPERHOUR
  53 #define SECSPERHOUR     (SECSPERMIN * MINSPERHOUR)
  54 #endif /* !defined SECSPERHOUR */
  55
  56 #ifndef HOURSPERDAY
  57 #define HOURSPERDAY     24
  58 #endif /* !defined HOURSPERDAY */
  59
  60 #ifndef EPOCH_YEAR
  61 #define EPOCH_YEAR      1970
  62 #endif /* !defined EPOCH_YEAR */
  63
  64 #ifndef TM_YEAR_BASE
  65 #define TM_YEAR_BASE    1900
  66 #endif /* !defined TM_YEAR_BASE */
  67
  68 #ifndef DAYSPERNYEAR
  69 #define DAYSPERNYEAR    365
  70 #endif /* !defined DAYSPERNYEAR */
  71
  72 #ifndef isleap
  73 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
  74 #endif /* !defined isleap */
  75
  76 #ifndef isleap_sum
  77 /*
  78 ** See tzfile.h for details on isleap_sum.
  79 */
  80 #define isleap_sum(a, b)        isleap((a) % 400 + (b) % 400)
  81 #endif /* !defined isleap_sum */
  82
  83 #define SECSPERDAY      ((long) SECSPERHOUR * HOURSPERDAY)
  84 #define SECSPERNYEAR    (SECSPERDAY * DAYSPERNYEAR)
  85 #define SECSPERLYEAR    (SECSPERNYEAR + SECSPERDAY)
  86
  87 #if HAVE_GETTEXT
  88 #include "locale.h"     /* for setlocale */
  89 #include "libintl.h"
  90 #endif /* HAVE_GETTEXT */
  91
  92 #ifndef GNUC_or_lint
  93 #ifdef lint
  94 #define GNUC_or_lint
  95 #else /* !defined lint */
  96 #ifdef __GNUC__
  97 #define GNUC_or_lint
  98 #endif /* defined __GNUC__ */
  99 #endif /* !defined lint */
 100 #endif /* !defined GNUC_or_lint */
 101
 102 #ifndef INITIALIZE
 103 #ifdef GNUC_or_lint
 104 #define INITIALIZE(x)   ((x) = 0)
 105 #else /* !defined GNUC_or_lint */
 106 #define INITIALIZE(x)
 107 #endif /* !defined GNUC_or_lint */
 108 #endif /* !defined INITIALIZE */
 109
 110 /*
 111 ** For the benefit of GNU folk...
 112 ** `_(MSGID)' uses the current locale's message library string for MSGID.
 113 ** The default is to use gettext if available, and use MSGID otherwise.
 114 */
 115
 116 #ifndef _
 117 #if HAVE_GETTEXT
 118 #define _(msgid) gettext(msgid)
 119 #else /* !HAVE_GETTEXT */
 120 #define _(msgid) msgid
 121 #endif /* !HAVE_GETTEXT */
 122 #endif /* !defined _ */
 123
 124 #ifndef TZ_DOMAIN
 125 #define TZ_DOMAIN "tz"
 126 #endif /* !defined TZ_DOMAIN */
 127
 128 #ifndef P
 129 #ifdef __STDC__
 130 #define P(x)    x
 131 #else /* !defined __STDC__ */
 132 #define P(x)    ()
 133 #endif /* !defined __STDC__ */
 134 #endif /* !defined P */
 135
 136 extern char **  environ;
 137 extern int      getopt P((int argc, char * const argv[],
 138                         const char * options));
 139 extern char *   optarg;
 140 extern int      optind;
 141 extern char *   tzname[2];
 142
 143 static time_t   absolute_min_time;
 144 static time_t   absolute_max_time;
 145 static size_t   longest;
 146 static char *   progname;
 147
 148 static char *   abbr P((struct tm * tmp));
 149 static long     delta P((struct tm * newp, struct tm * oldp));
 150 static void     dumptime P((const struct tm * tmp));
 151 static time_t   hunt P((char * name, time_t lot, time_t hit));
 152 static void     setabsolutes P((void));
 153 static void     show P((char * zone, time_t t, int v));
 154 static const char *     tformat P((void));
 155 static time_t   yeartot P((long y));
 156
 157 #ifndef TYPECHECK
 158 #define my_localtime    localtime
 159 #else /* !defined TYPECHECK */
 160 static struct tm *
 161 my_localtime(tp)
 162 time_t *        tp;
 163 {
 164         register struct tm *    tmp;
 165
 166         tmp = localtime(tp);
 167         if (tp != NULL && tmp != NULL) {
 168                 struct tm       tm;
 169                 register time_t t;
 170
 171                 tm = *tmp;
 172                 t = mktime(&tm);
 173                 if (t - *tp >= 1 || *tp - t >= 1) {
 174                         (void) fflush(stdout);
 175                         (void) fprintf(stderr, "\n%s: ", progname);
 176                         (void) fprintf(stderr, tformat(), *tp);
 177                         (void) fprintf(stderr, " ->");
 178                         (void) fprintf(stderr, " year=%d", tmp->tm_year);
 179                         (void) fprintf(stderr, " mon=%d", tmp->tm_mon);
 180                         (void) fprintf(stderr, " mday=%d", tmp->tm_mday);
 181                         (void) fprintf(stderr, " hour=%d", tmp->tm_hour);
 182                         (void) fprintf(stderr, " min=%d", tmp->tm_min);
 183                         (void) fprintf(stderr, " sec=%d", tmp->tm_sec);
 184                         (void) fprintf(stderr, " isdst=%d", tmp->tm_isdst);
 185                         (void) fprintf(stderr, " -> ");
 186                         (void) fprintf(stderr, tformat(), t);
 187                         (void) fprintf(stderr, "\n");
 188                 }
 189         }
 190         return tmp;
 191 }
 192 #endif /* !defined TYPECHECK */
 193
 194 int
 195 main(argc, argv)
 196 int     argc;
 197 char *  argv[];
 198 {
 199         register int            i;
 200         register int            c;
 201         register int            vflag;
 202         register char *         cutarg;
 203         register long           cutloyear = ZDUMP_LO_YEAR;
 204         register long           cuthiyear = ZDUMP_HI_YEAR;
 205         register time_t         cutlotime;
 206         register time_t         cuthitime;
 207         register char **        fakeenv;
 208         time_t                  now;
 209         time_t                  t;
 210         time_t                  newt;
 211         struct tm               tm;
 212         struct tm               newtm;
 213         register struct tm *    tmp;
 214         register struct tm *    newtmp;
 215
 216         INITIALIZE(cutlotime);
 217         INITIALIZE(cuthitime);
 218 #if HAVE_GETTEXT
 219         (void) setlocale(LC_MESSAGES, "");
 220 #ifdef TZ_DOMAINDIR
 221         (void) bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR);
 222 #endif /* defined TEXTDOMAINDIR */
 223         (void) textdomain(TZ_DOMAIN);
 224 #endif /* HAVE_GETTEXT */
 225         progname = argv[0];
 226         for (i = 1; i < argc; ++i)
 227                 if (strcmp(argv[i], "--version") == 0) {
 228                         (void) printf("%s\n", elsieid);
 229                         (void) exit(EXIT_SUCCESS);
 230                 }
 231         vflag = 0;
 232         cutarg = NULL;
 233         while ((c = getopt(argc, argv, "c:v")) == 'c' || c == 'v')
 234                 if (c == 'v')
 235                         vflag = 1;
 236                 else    cutarg = optarg;
 237         if ((c != EOF && c != -1) ||
 238                 (optind == argc - 1 && strcmp(argv[optind], "=") == 0)) {
 239                         (void) fprintf(stderr,
 240 _("%s: usage is %s [ --version ] [ -v ] [ -c [loyear,]hiyear ] zonename ...\n"),
 241                                 progname, progname);
 242                         (void) exit(EXIT_FAILURE);
 243         }
 244         if (vflag) {
 245                 if (cutarg != NULL) {
 246                         long    lo;
 247                         long    hi;
 248                         char    dummy;
 249
 250                         if (sscanf(cutarg, "%ld%c", &hi, &dummy) == 1) {
 251                                 cuthiyear = hi;
 252                         } else if (sscanf(cutarg, "%ld,%ld%c",
 253                                 &lo, &hi, &dummy) == 2) {
 254                                         cutloyear = lo;
 255                                         cuthiyear = hi;
 256                         } else {
 257 (void) fprintf(stderr, _("%s: wild -c argument %s\n"),
 258                                         progname, cutarg);
 259                                 (void) exit(EXIT_FAILURE);
 260                         }
 261                 }
 262                 setabsolutes();
 263                 cutlotime = yeartot(cutloyear);
 264                 cuthitime = yeartot(cuthiyear);
 265         }
 266         (void) time(&now);
 267         longest = 0;
 268         for (i = optind; i < argc; ++i)
 269                 if (strlen(argv[i]) > longest)
 270                         longest = strlen(argv[i]);
 271         {
 272                 register int    from;
 273                 register int    to;
 274
 275                 for (i = 0; environ[i] != NULL; ++i)
 276                         continue;
 277                 fakeenv = (char **) malloc((size_t) ((i + 2) *
 278                         sizeof *fakeenv));
 279                 if (fakeenv == NULL ||
 280                         (fakeenv[0] = (char *) malloc(longest + 4)) == NULL) {
 281                                         (void) perror(progname);
 282                                         (void) exit(EXIT_FAILURE);
 283                 }
 284                 to = 0;
 285                 (void) strcpy(fakeenv[to++], "TZ=");
 286                 for (from = 0; environ[from] != NULL; ++from)
 287                         if (strncmp(environ[from], "TZ=", 3) != 0)
 288                                 fakeenv[to++] = environ[from];
 289                 fakeenv[to] = NULL;
 290                 environ = fakeenv;
 291         }
 292         for (i = optind; i < argc; ++i) {
 293                 static char     buf[MAX_STRING_LENGTH];
 294
 295                 (void) strcpy(&fakeenv[0][3], argv[i]);
 296                 if (!vflag) {
 297                         show(argv[i], now, FALSE);
 298                         continue;
 299                 }
 300                 t = absolute_min_time;
 301                 show(argv[i], t, TRUE);
 302                 t += SECSPERHOUR * HOURSPERDAY;
 303                 show(argv[i], t, TRUE);
 304                 if (t < cutlotime)
 305                         t = cutlotime;
 306                 tmp = my_localtime(&t);
 307                 if (tmp != NULL) {
 308                         tm = *tmp;
 309                         (void) strncpy(buf, abbr(&tm), (sizeof buf) - 1);
 310                 }
 311                 for ( ; ; ) {
 312                         if (t >= cuthitime)
 313                                 break;
 314                         newt = t + SECSPERHOUR * 12;
 315                         if (newt >= cuthitime)
 316                                 break;
 317                         if (newt <= t)
 318                                 break;
 319                         newtmp = localtime(&newt);
 320                         if (newtmp != NULL)
 321                                 newtm = *newtmp;
 322                         if ((tmp == NULL || newtmp == NULL) ? (tmp != newtmp) :
 323                                 (delta(&newtm, &tm) != (newt - t) ||
 324                                 newtm.tm_isdst != tm.tm_isdst ||
 325                                 strcmp(abbr(&newtm), buf) != 0)) {
 326                                         newt = hunt(argv[i], t, newt);
 327                                         newtmp = localtime(&newt);
 328                                         if (newtmp != NULL) {
 329                                                 newtm = *newtmp;
 330                                                 (void) strncpy(buf,
 331                                                         abbr(&newtm),
 332                                                         (sizeof buf) - 1);
 333                                         }
 334                         }
 335                         t = newt;
 336                         tm = newtm;
 337                         tmp = newtmp;
 338                 }
 339                 t = absolute_max_time;
 340                 t -= SECSPERHOUR * HOURSPERDAY;
 341                 show(argv[i], t, TRUE);
 342                 t += SECSPERHOUR * HOURSPERDAY;
 343                 show(argv[i], t, TRUE);
 344         }
 345         if (fflush(stdout) || ferror(stdout)) {
 346                 (void) fprintf(stderr, "%s: ", progname);
 347                 (void) perror(_("Error writing standard output"));
 348                 (void) exit(EXIT_FAILURE);
 349         }
 350         exit(EXIT_SUCCESS);
 351         /* If exit fails to exit... */
 352         return EXIT_FAILURE;
 353 }
 354
 355 static void
 356 setabsolutes()
 357 {
 358         if (0.5 == (time_t) 0.5) {
 359                 /*
 360                 ** time_t is floating.
 361                 */
 362                 if (sizeof (time_t) == sizeof (float)) {
 363                         absolute_min_time = (time_t) -FLT_MAX;
 364                         absolute_max_time = (time_t) FLT_MAX;
 365                 } else if (sizeof (time_t) == sizeof (double)) {
 366                         absolute_min_time = (time_t) -DBL_MAX;
 367                         absolute_max_time = (time_t) DBL_MAX;
 368                 } else {
 369                         (void) fprintf(stderr,
 370 _("%s: use of -v on system with floating time_t other than float or double\n"),
 371                                 progname);
 372                         (void) exit(EXIT_FAILURE);
 373                 }
 374         } else if (0 > (time_t) -1) {
 375                 /*
 376                 ** time_t is signed.
 377                 */
 378                 register time_t hibit;
 379
 380                 for (hibit = 1; (hibit * 2) != 0; hibit *= 2)
 381                         continue;
 382                 absolute_min_time = hibit;
 383                 absolute_max_time = -(hibit + 1);
 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 time_t
 394 yeartot(y)
 395 const long      y;
 396 {
 397         register long   myy;
 398         register long   seconds;
 399         register time_t t;
 400
 401         myy = EPOCH_YEAR;
 402         t = 0;
 403         while (myy != y) {
 404                 if (myy < y) {
 405                         seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
 406                         ++myy;
 407                         if (t > absolute_max_time - seconds) {
 408                                 t = absolute_max_time;
 409                                 break;
 410                         }
 411                         t += seconds;
 412                 } else {
 413                         --myy;
 414                         seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
 415                         if (t < absolute_min_time + seconds) {
 416                                 t = absolute_min_time;
 417                                 break;
 418                         }
 419                         t -= seconds;
 420                 }
 421         }
 422         return t;
 423 }
 424
 425 static time_t
 426 hunt(name, lot, hit)
 427 char *  name;
 428 time_t  lot;
 429 time_t  hit;
 430 {
 431         time_t                  t;
 432         long                    diff;
 433         struct tm               lotm;
 434         register struct tm *    lotmp;
 435         struct tm               tm;
 436         register struct tm *    tmp;
 437         char                    loab[MAX_STRING_LENGTH];
 438
 439         lotmp = my_localtime(&lot);
 440         if (lotmp != NULL) {
 441                 lotm = *lotmp;
 442                 (void) strncpy(loab, abbr(&lotm), (sizeof loab) - 1);
 443         }
 444         for ( ; ; ) {
 445                 diff = (long) (hit - lot);
 446                 if (diff < 2)
 447                         break;
 448                 t = lot;
 449                 t += diff / 2;
 450                 if (t <= lot)
 451                         ++t;
 452                 else if (t >= hit)
 453                         --t;
 454                 tmp = my_localtime(&t);
 455                 if (tmp != NULL)
 456                         tm = *tmp;
 457                 if ((lotmp == NULL || tmp == NULL) ? (lotmp == tmp) :
 458                         (delta(&tm, &lotm) == (t - lot) &&
 459                         tm.tm_isdst == lotm.tm_isdst &&
 460                         strcmp(abbr(&tm), loab) == 0)) {
 461                                 lot = t;
 462                                 lotm = tm;
 463                                 lotmp = tmp;
 464                 } else  hit = t;
 465         }
 466         show(name, lot, TRUE);
 467         show(name, hit, TRUE);
 468         return hit;
 469 }
 470
 471 /*
 472 ** Thanks to Paul Eggert (eggert@twinsun.com) for logic used in delta.
 473 */
 474
 475 static long
 476 delta(newp, oldp)
 477 struct tm *     newp;
 478 struct tm *     oldp;
 479 {
 480         register long   result;
 481         register int    tmy;
 482
 483         if (newp->tm_year < oldp->tm_year)
 484                 return -delta(oldp, newp);
 485         result = 0;
 486         for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy)
 487                 result += DAYSPERNYEAR + isleap_sum(tmy, TM_YEAR_BASE);
 488         result += newp->tm_yday - oldp->tm_yday;
 489         result *= HOURSPERDAY;
 490         result += newp->tm_hour - oldp->tm_hour;
 491         result *= MINSPERHOUR;
 492         result += newp->tm_min - oldp->tm_min;
 493         result *= SECSPERMIN;
 494         result += newp->tm_sec - oldp->tm_sec;
 495         return result;
 496 }
 497
 498 static void
 499 show(zone, t, v)
 500 char *  zone;
 501 time_t  t;
 502 int     v;
 503 {
 504         register struct tm *    tmp;
 505
 506         (void) printf("%-*s  ", (int) longest, zone);
 507         if (v) {
 508                 tmp = gmtime(&t);
 509                 if (tmp == NULL) {
 510                         (void) printf(tformat(), t);
 511                 } else {
 512                         dumptime(tmp);
 513                         (void) printf(" UTC");
 514                 }
 515                 (void) printf(" = ");
 516         }
 517         tmp = my_localtime(&t);
 518         dumptime(tmp);
 519         if (tmp != NULL) {
 520                 if (*abbr(tmp) != '\0')
 521                         (void) printf(" %s", abbr(tmp));
 522                 if (v) {
 523                         (void) printf(" isdst=%d", tmp->tm_isdst);
 524 #ifdef TM_GMTOFF
 525                         (void) printf(" gmtoff=%ld", tmp->TM_GMTOFF);
 526 #endif /* defined TM_GMTOFF */
 527                 }
 528         }
 529         (void) printf("\n");
 530 }
 531
 532 static char *
 533 abbr(tmp)
 534 struct tm *     tmp;
 535 {
 536         register 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()
 552 {
 553         if (0.5 == (time_t) 0.5) {      /* floating */
 554                 if (sizeof (time_t) > sizeof (double))
 555                         return "%Lg";
 556                 return "%g";
 557         }
 558         if (0 > (time_t) -1) {          /* signed */
 559                 if (sizeof (time_t) > sizeof (long))
 560                         return "%lld";
 561                 if (sizeof (time_t) > sizeof (int))
 562                         return "%ld";
 563                 return "%d";
 564         }
 565         if (sizeof (time_t) > sizeof (unsigned long))
 566                 return "%llu";
 567         if (sizeof (time_t) > sizeof (unsigned int))
 568                 return "%lu";
 569         return "%u";
 570 }
 571
 572 static void
 573 dumptime(timeptr)
 574 register const struct tm *      timeptr;
 575 {
 576         static const char       wday_name[][3] = {
 577                 "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
 578         };
 579         static const char       mon_name[][3] = {
 580                 "Jan", "Feb", "Mar", "Apr", "May", "Jun",
 581                 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
 582         };
 583         register const char *   wn;
 584         register const char *   mn;
 585         register int            lead;
 586         register int            trail;
 587
 588         if (timeptr == NULL) {
 589                 (void) printf("NULL");
 590                 return;
 591         }
 592         /*
 593         ** The packaged versions of localtime and gmtime never put out-of-range
 594         ** values in tm_wday or tm_mon, but since this code might be compiled
 595         ** with other (perhaps experimental) versions, paranoia is in order.
 596         */
 597         if (timeptr->tm_wday < 0 || timeptr->tm_wday >=
 598                 (int) (sizeof wday_name / sizeof wday_name[0]))
 599                         wn = "???";
 600         else            wn = wday_name[timeptr->tm_wday];
 601         if (timeptr->tm_mon < 0 || timeptr->tm_mon >=
 602                 (int) (sizeof mon_name / sizeof mon_name[0]))
 603                         mn = "???";
 604         else            mn = mon_name[timeptr->tm_mon];
 605         (void) printf("%.3s %.3s%3d %.2d:%.2d:%.2d ",
 606                 wn, mn,
 607                 timeptr->tm_mday, timeptr->tm_hour,
 608                 timeptr->tm_min, timeptr->tm_sec);
 609 #define DIVISOR 10
 610         trail = timeptr->tm_year % DIVISOR + TM_YEAR_BASE % DIVISOR;
 611         lead = timeptr->tm_year / DIVISOR + TM_YEAR_BASE / DIVISOR +
 612                 trail / DIVISOR;
 613         trail %= DIVISOR;
 614         if (trail < 0 && lead > 0) {
 615                 trail += DIVISOR;
 616                 --lead;
 617         } else if (lead < 0 && trail > 0) {
 618                 trail -= DIVISOR;
 619                 ++lead;
 620         }
 621         if (lead == 0)
 622                 (void) printf("%d", trail);
 623         else    (void) printf("%d%d", lead, ((trail < 0) ? -trail : trail));
 624 }