contrib/tzcode/zic/zdump.c

   1 /*
   2 ** This file is in the public domain, so clarified as of
   3 ** 2009-05-17 by Arthur David Olson.
   4 */
   5
   6 #ifndef lint
   7 static const char rcsid[] =
   8   "$FreeBSD$";
   9 static char     elsieid[] = "@(#)zdump.c        8.10";
  10 #endif /* not lint */
  11
  12 /*
  13 ** This code has been made independent of the rest of the time
  14 ** conversion package to increase confidence in the verification it provides.
  15 ** You can use this code to help in verifying other implementations.
  16 */
  17
  18 #include <err.h>
  19 #include <stdio.h>      /* for stdout, stderr */
  20 #include <stdlib.h>     /* for exit, malloc, atoi */
  21 #include <string.h>     /* for strcpy */
  22 #include <sys/types.h>  /* for time_t */
  23 #include <time.h>       /* for struct tm */
  24 #include <unistd.h>
  25 #include <float.h>      /* for FLT_MAX and DBL_MAX */
  26 #include <ctype.h>      /* for isalpha et al. */
  27 #ifndef isascii
  28 #define isascii(x) 1
  29 #endif /* !defined isascii */
  30
  31 #ifndef ZDUMP_LO_YEAR
  32 #define ZDUMP_LO_YEAR   (-500)
  33 #endif /* !defined ZDUMP_LO_YEAR */
  34
  35 #ifndef ZDUMP_HI_YEAR
  36 #define ZDUMP_HI_YEAR   2500
  37 #endif /* !defined ZDUMP_HI_YEAR */
  38
  39 #ifndef MAX_STRING_LENGTH
  40 #define MAX_STRING_LENGTH       1024
  41 #endif /* !defined MAX_STRING_LENGTH */
  42
  43 #ifndef TRUE
  44 #define TRUE            1
  45 #endif /* !defined TRUE */
  46
  47 #ifndef FALSE
  48 #define FALSE           0
  49 #endif /* !defined FALSE */
  50
  51 #ifndef EXIT_SUCCESS
  52 #define EXIT_SUCCESS    0
  53 #endif /* !defined EXIT_SUCCESS */
  54
  55 #ifndef EXIT_FAILURE
  56 #define EXIT_FAILURE    1
  57 #endif /* !defined EXIT_FAILURE */
  58
  59 #ifndef SECSPERMIN
  60 #define SECSPERMIN      60
  61 #endif /* !defined SECSPERMIN */
  62
  63 #ifndef MINSPERHOUR
  64 #define MINSPERHOUR     60
  65 #endif /* !defined MINSPERHOUR */
  66
  67 #ifndef SECSPERHOUR
  68 #define SECSPERHOUR     (SECSPERMIN * MINSPERHOUR)
  69 #endif /* !defined SECSPERHOUR */
  70
  71 #ifndef HOURSPERDAY
  72 #define HOURSPERDAY     24
  73 #endif /* !defined HOURSPERDAY */
  74
  75 #ifndef EPOCH_YEAR
  76 #define EPOCH_YEAR      1970
  77 #endif /* !defined EPOCH_YEAR */
  78
  79 #ifndef TM_YEAR_BASE
  80 #define TM_YEAR_BASE    1900
  81 #endif /* !defined TM_YEAR_BASE */
  82
  83 #ifndef DAYSPERNYEAR
  84 #define DAYSPERNYEAR    365
  85 #endif /* !defined DAYSPERNYEAR */
  86
  87 #ifndef isleap
  88 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
  89 #endif /* !defined isleap */
  90
  91 #ifndef isleap_sum
  92 /*
  93 ** See tzfile.h for details on isleap_sum.
  94 */
  95 #define isleap_sum(a, b)        isleap((a) % 400 + (b) % 400)
  96 #endif /* !defined isleap_sum */
  97
  98 #define SECSPERDAY      ((long) SECSPERHOUR * HOURSPERDAY)
  99 #define SECSPERNYEAR    (SECSPERDAY * DAYSPERNYEAR)
 100 #define SECSPERLYEAR    (SECSPERNYEAR + SECSPERDAY)
 101
 102 #ifndef HAVE_GETTEXT
 103 #define HAVE_GETTEXT 0
 104 #endif
 105 #if HAVE_GETTEXT
 106 #include "locale.h"     /* for setlocale */
 107 #include "libintl.h"
 108 #endif /* HAVE_GETTEXT */
 109
 110 #ifndef GNUC_or_lint
 111 #ifdef lint
 112 #define GNUC_or_lint
 113 #else /* !defined lint */
 114 #ifdef __GNUC__
 115 #define GNUC_or_lint
 116 #endif /* defined __GNUC__ */
 117 #endif /* !defined lint */
 118 #endif /* !defined GNUC_or_lint */
 119
 120 #ifndef INITIALIZE
 121 #ifdef GNUC_or_lint
 122 #define INITIALIZE(x)   ((x) = 0)
 123 #else /* !defined GNUC_or_lint */
 124 #define INITIALIZE(x)
 125 #endif /* !defined GNUC_or_lint */
 126 #endif /* !defined INITIALIZE */
 127
 128 /*
 129 ** For the benefit of GNU folk...
 130 ** `_(MSGID)' uses the current locale's message library string for MSGID.
 131 ** The default is to use gettext if available, and use MSGID otherwise.
 132 */
 133
 134 #ifndef _
 135 #if HAVE_GETTEXT
 136 #define _(msgid) gettext(msgid)
 137 #else /* !(HAVE_GETTEXT) */
 138 #define _(msgid) msgid
 139 #endif /* !(HAVE_GETTEXT) */
 140 #endif /* !defined _ */
 141
 142 #ifndef TZ_DOMAIN
 143 #define TZ_DOMAIN "tz"
 144 #endif /* !defined TZ_DOMAIN */
 145
 146 extern char **  environ;
 147 extern char *   tzname[2];
 148
 149 static time_t   absolute_min_time;
 150 static time_t   absolute_max_time;
 151 static size_t   longest;
 152 static char *   progname;
 153 static int      warned;
 154
 155 static void     usage(FILE *stream, int status);
 156 static char *   abbr(struct tm * tmp);
 157 static void     abbrok(const char * abbrp, const char * zone);
 158 static long     delta(struct tm * newp, struct tm * oldp);
 159 static void     dumptime(const struct tm * tmp);
 160 static time_t   hunt(char * name, time_t lot, time_t    hit);
 161 static void     setabsolutes(void);
 162 static void     show(char * zone, time_t t, int v);
 163 static const char *     tformat(void);
 164 static time_t   yeartot(long y);
 165
 166 #ifndef TYPECHECK
 167 #define my_localtime    localtime
 168 #else /* !defined TYPECHECK */
 169 static struct tm *
 170 my_localtime(tp)
 171 time_t *        tp;
 172 {
 173         register struct tm *    tmp;
 174
 175         tmp = localtime(tp);
 176         if (tp != NULL && tmp != NULL) {
 177                 struct tm       tm;
 178                 register time_t t;
 179
 180                 tm = *tmp;
 181                 t = mktime(&tm);
 182                 if (t - *tp >= 1 || *tp - t >= 1) {
 183                         (void) fflush(stdout);
 184                         (void) fprintf(stderr, "\n%s: ", progname);
 185                         (void) fprintf(stderr, tformat(), *tp);
 186                         (void) fprintf(stderr, " ->");
 187                         (void) fprintf(stderr, " year=%d", tmp->tm_year);
 188                         (void) fprintf(stderr, " mon=%d", tmp->tm_mon);
 189                         (void) fprintf(stderr, " mday=%d", tmp->tm_mday);
 190                         (void) fprintf(stderr, " hour=%d", tmp->tm_hour);
 191                         (void) fprintf(stderr, " min=%d", tmp->tm_min);
 192                         (void) fprintf(stderr, " sec=%d", tmp->tm_sec);
 193                         (void) fprintf(stderr, " isdst=%d", tmp->tm_isdst);
 194                         (void) fprintf(stderr, " -> ");
 195                         (void) fprintf(stderr, tformat(), t);
 196                         (void) fprintf(stderr, "\n");
 197                 }
 198         }
 199         return tmp;
 200 }
 201 #endif /* !defined TYPECHECK */
 202
 203 static void
 204 abbrok(abbrp, zone)
 205 const char * const      abbrp;
 206 const char * const      zone;
 207 {
 208         register const char *   cp;
 209         register char *         wp;
 210
 211         if (warned)
 212                 return;
 213         cp = abbrp;
 214         wp = NULL;
 215         while (isascii((unsigned char) *cp) &&
 216                 (isalnum((unsigned char)*cp) || *cp == '-' || *cp == '+'))
 217                 ++cp;
 218         if (cp - abbrp < 3)
 219                 wp = _("has fewer than 3 characters");
 220         else if (cp - abbrp > 6)
 221                 wp = _("has more than 6 characters");
 222         else if (*cp)
 223                 wp = "has characters other than ASCII alphanumerics, '-' or '+'";
 224         else
 225                 return;
 226         (void) fflush(stdout);
 227         (void) fprintf(stderr,
 228                 _("%s: warning: zone \"%s\" abbreviation \"%s\" %s\n"),
 229                 progname, zone, abbrp, wp);
 230         warned = TRUE;
 231 }
 232
 233 int
 234 main(argc, argv)
 235 int     argc;
 236 char *  argv[];
 237 {
 238         register int            i;
 239         register int            c;
 240         register int            vflag;
 241         register char *         cutarg;
 242         register long           cutloyear = ZDUMP_LO_YEAR;
 243         register long           cuthiyear = ZDUMP_HI_YEAR;
 244         register time_t         cutlotime;
 245         register time_t         cuthitime;
 246         register char **        fakeenv;
 247         time_t                  now;
 248         time_t                  t;
 249         time_t                  newt;
 250         struct tm               tm;
 251         struct tm               newtm;
 252         register struct tm *    tmp;
 253         register struct tm *    newtmp;
 254
 255         progname=argv[0];
 256         INITIALIZE(cutlotime);
 257         INITIALIZE(cuthitime);
 258 #if HAVE_GETTEXT
 259         (void) setlocale(LC_MESSAGES, "");
 260 #ifdef TZ_DOMAINDIR
 261         (void) bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR);
 262 #endif /* TEXTDOMAINDIR */
 263         (void) textdomain(TZ_DOMAIN);
 264 #endif /* HAVE_GETTEXT */
 265         for (i = 1; i < argc; ++i)
 266                 if (strcmp(argv[i], "--version") == 0) {
 267                         errx(EXIT_SUCCESS, "%s", elsieid);
 268                 } else if (strcmp(argv[i], "--help") == 0) {
 269                         usage(stdout, EXIT_SUCCESS);
 270                 }
 271         vflag = 0;
 272         cutarg = NULL;
 273         while ((c = getopt(argc, argv, "c:v")) == 'c' || c == 'v')
 274                 if (c == 'v')
 275                         vflag = 1;
 276                 else    cutarg = optarg;
 277         if ((c != -1) ||
 278                 (optind == argc - 1 && strcmp(argv[optind], "=") == 0)) {
 279                         usage(stderr, EXIT_FAILURE);
 280         }
 281         if (vflag) {
 282                 if (cutarg != NULL) {
 283                         long    lo;
 284                         long    hi;
 285                         char    dummy;
 286
 287                         if (sscanf(cutarg, "%ld%c", &hi, &dummy) == 1) {
 288                                 cuthiyear = hi;
 289                         } else if (sscanf(cutarg, "%ld,%ld%c",
 290                                 &lo, &hi, &dummy) == 2) {
 291                                         cutloyear = lo;
 292                                         cuthiyear = hi;
 293                         } else {
 294 (void) fprintf(stderr, _("%s: wild -c argument %s\n"),
 295                                         progname, cutarg);
 296                                 exit(EXIT_FAILURE);
 297                         }
 298                 }
 299                 setabsolutes();
 300                 cutlotime = yeartot(cutloyear);
 301                 cuthitime = yeartot(cuthiyear);
 302         }
 303         (void) time(&now);
 304         longest = 0;
 305         for (i = optind; i < argc; ++i)
 306                 if (strlen(argv[i]) > longest)
 307                         longest = strlen(argv[i]);
 308         {
 309                 register int    from;
 310                 register int    to;
 311
 312                 for (i = 0;  environ[i] != NULL; ++i)
 313                         continue;
 314                 fakeenv = (char **) malloc((size_t) ((i + 2) *
 315                         sizeof *fakeenv));
 316                 if (fakeenv == NULL ||
 317                         (fakeenv[0] = (char *) malloc((size_t) (longest +
 318                                 4))) == NULL)
 319                                         errx(EXIT_FAILURE,
 320                                              _("malloc() failed"));
 321                 to = 0;
 322                 (void) strcpy(fakeenv[to++], "TZ=");
 323                 for (from = 0; environ[from] != NULL; ++from)
 324                         if (strncmp(environ[from], "TZ=", 3) != 0)
 325                                 fakeenv[to++] = environ[from];
 326                 fakeenv[to] = NULL;
 327                 environ = fakeenv;
 328         }
 329         for (i = optind; i < argc; ++i) {
 330                 static char     buf[MAX_STRING_LENGTH];
 331
 332                 (void) strcpy(&fakeenv[0][3], argv[i]);
 333                 if (!vflag) {
 334                         show(argv[i], now, FALSE);
 335                         continue;
 336                 }
 337                 warned = FALSE;
 338                 t = absolute_min_time;
 339                 show(argv[i], t, TRUE);
 340                 t += SECSPERHOUR * HOURSPERDAY;
 341                 show(argv[i], t, TRUE);
 342                 if (t < cutlotime)
 343                         t = cutlotime;
 344                 tmp = my_localtime(&t);
 345                 if (tmp != NULL) {
 346                         tm = *tmp;
 347                         (void) strncpy(buf, abbr(&tm), (sizeof buf) - 1);
 348                 }
 349                 for ( ; ; ) {
 350                         if (t >= cuthitime || t >= cuthitime - SECSPERHOUR * 12)
 351                                 break;
 352                         newt = t + SECSPERHOUR * 12;
 353                         newtmp = localtime(&newt);
 354                         if (newtmp != NULL)
 355                                 newtm = *newtmp;
 356                         if ((tmp == NULL || newtmp == NULL) ? (tmp != newtmp) :
 357                                 (delta(&newtm, &tm) != (newt - t) ||
 358                                 newtm.tm_isdst != tm.tm_isdst ||
 359                                 strcmp(abbr(&newtm), buf) != 0)) {
 360                                         newt = hunt(argv[i], t, newt);
 361                                         newtmp = localtime(&newt);
 362                                         if (newtmp != NULL) {
 363                                                 newtm = *newtmp;
 364                                                 (void) strncpy(buf,
 365                                                         abbr(&newtm),
 366                                                         (sizeof buf) - 1);
 367                                         }
 368                         }
 369                         t = newt;
 370                         tm = newtm;
 371                         tmp = newtmp;
 372                 }
 373                 t = absolute_max_time;
 374                 t -= SECSPERHOUR * HOURSPERDAY;
 375                 show(argv[i], t, TRUE);
 376                 t += SECSPERHOUR * HOURSPERDAY;
 377                 show(argv[i], t, TRUE);
 378         }
 379         if (fflush(stdout) || ferror(stdout))
 380                 errx(EXIT_FAILURE, _("error writing standard output"));
 381         exit(EXIT_SUCCESS);
 382         /* If exit fails to exit... */
 383         return(EXIT_FAILURE);
 384 }
 385
 386 static void
 387 setabsolutes(void)
 388 {
 389         if (0.5 == (time_t) 0.5) {
 390                 /*
 391                 ** time_t is floating.
 392                 */
 393                 if (sizeof (time_t) == sizeof (float)) {
 394                         absolute_min_time = (time_t) -FLT_MAX;
 395                         absolute_max_time = (time_t) FLT_MAX;
 396                 } else if (sizeof (time_t) == sizeof (double)) {
 397                         absolute_min_time = (time_t) -DBL_MAX;
 398                         absolute_max_time = (time_t) DBL_MAX;
 399                 } else {
 400                         (void) fprintf(stderr,
 401 _("%s: use of -v on system with floating time_t other than float or double\n"),
 402                                 progname);
 403                         exit(EXIT_FAILURE);
 404                 }
 405         } else if (0 > (time_t) -1) {
 406                 /*
 407                 ** time_t is signed.  Assume overflow wraps around.
 408                 */
 409                 time_t t = 0;
 410                 time_t t1 = 1;
 411
 412                 while (t < t1) {
 413                         t = t1;
 414                         t1 = 2 * t1 + 1;
 415                 }
 416
 417                 absolute_max_time = t;
 418                 t = -t;
 419                 absolute_min_time = t - 1;
 420                 if (t < absolute_min_time)
 421                         absolute_min_time = t;
 422         } else {
 423                 /*
 424                 ** time_t is unsigned.
 425                 */
 426                 absolute_min_time = 0;
 427                 absolute_max_time = absolute_min_time - 1;
 428         }
 429 }
 430
 431 static time_t
 432 yeartot(y)
 433 const long      y;
 434 {
 435         register long   myy;
 436         register long   seconds;
 437         register time_t t;
 438
 439         myy = EPOCH_YEAR;
 440         t = 0;
 441         while (myy != y) {
 442                 if (myy < y) {
 443                         seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
 444                         ++myy;
 445                         if (t > absolute_max_time - seconds) {
 446                                 t = absolute_max_time;
 447                                 break;
 448                         }
 449                         t += seconds;
 450                 } else {
 451                         --myy;
 452                         seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
 453                         if (t < absolute_min_time + seconds) {
 454                                 t = absolute_min_time;
 455                                 break;
 456                         }
 457                         t -= seconds;
 458                 }
 459         }
 460         return t;
 461 }
 462
 463 static void
 464 usage(FILE *stream, int status)
 465 {
 466         fprintf(stream,
 467 _("usage: %s [--version] [-v] [--help] [-c [loyear,]hiyear] zonename ...\n\
 468 \n\
 469 Report bugs to tz@elsie.nci.nih.gov.\n"), progname);
 470         exit(status);
 471 }
 472
 473 static time_t
 474 hunt(char *name, time_t lot, time_t hit)
 475 {
 476         time_t                  t;
 477         long                    diff;
 478         struct tm               lotm;
 479         register struct tm *    lotmp;
 480         struct tm               tm;
 481         register struct tm *    tmp;
 482         char                    loab[MAX_STRING_LENGTH];
 483
 484         lotmp = my_localtime(&lot);
 485         if (lotmp != NULL) {
 486                 lotm = *lotmp;
 487                 (void) strncpy(loab, abbr(&lotm), (sizeof loab) - 1);
 488         }
 489         for ( ; ; ) {
 490                 diff = (long) (hit - lot);
 491                 if (diff < 2)
 492                         break;
 493                 t = lot;
 494                 t += diff / 2;
 495                 if (t <= lot)
 496                         ++t;
 497                 else if (t >= hit)
 498                         --t;
 499                 tmp = my_localtime(&t);
 500                 if (tmp != NULL)
 501                         tm = *tmp;
 502                 if ((lotmp == NULL || tmp == NULL) ? (lotmp == tmp) :
 503                         (delta(&tm, &lotm) == (t - lot) &&
 504                         tm.tm_isdst == lotm.tm_isdst &&
 505                         strcmp(abbr(&tm), loab) == 0)) {
 506                                 lot = t;
 507                                 lotm = tm;
 508                                 lotmp = tmp;
 509                 } else  hit = t;
 510         }
 511         show(name, lot, TRUE);
 512         show(name, hit, TRUE);
 513         return hit;
 514 }
 515
 516 /*
 517 ** Thanks to Paul Eggert for logic used in delta.
 518 */
 519
 520 static long
 521 delta(newp, oldp)
 522 struct tm *     newp;
 523 struct tm *     oldp;
 524 {
 525         register long   result;
 526         register int    tmy;
 527
 528         if (newp->tm_year < oldp->tm_year)
 529                 return -delta(oldp, newp);
 530         result = 0;
 531         for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy)
 532                 result += DAYSPERNYEAR + isleap_sum(tmy, TM_YEAR_BASE);
 533         result += newp->tm_yday - oldp->tm_yday;
 534         result *= HOURSPERDAY;
 535         result += newp->tm_hour - oldp->tm_hour;
 536         result *= MINSPERHOUR;
 537         result += newp->tm_min - oldp->tm_min;
 538         result *= SECSPERMIN;
 539         result += newp->tm_sec - oldp->tm_sec;
 540         return result;
 541 }
 542
 543 static void
 544 show(char *zone, time_t t, int v)
 545 {
 546         register struct tm *    tmp;
 547
 548         (void) printf("%-*s  ", (int) longest, zone);
 549         if (v) {
 550                 tmp = gmtime(&t);
 551                 if (tmp == NULL) {
 552                         (void) printf(tformat(), t);
 553                 } else {
 554                         dumptime(tmp);
 555                         (void) printf(" UTC");
 556                 }
 557                 (void) printf(" = ");
 558         }
 559         tmp = my_localtime(&t);
 560         dumptime(tmp);
 561         if (tmp != NULL) {
 562                 if (*abbr(tmp) != '\0')
 563                         (void) printf(" %s", abbr(tmp));
 564                 if (v) {
 565                         (void) printf(" isdst=%d", tmp->tm_isdst);
 566 #ifdef TM_GMTOFF
 567                         (void) printf(" gmtoff=%ld", tmp->TM_GMTOFF);
 568 #endif /* defined TM_GMTOFF */
 569                 }
 570         }
 571         (void) printf("\n");
 572         if (tmp != NULL && *abbr(tmp) != '\0')
 573                 abbrok(abbr(tmp), zone);
 574 }
 575
 576 static char *
 577 abbr(tmp)
 578 struct tm *     tmp;
 579 {
 580         register char * result;
 581         static char     nada;
 582
 583         if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1)
 584                 return &nada;
 585         result = tzname[tmp->tm_isdst];
 586         return (result == NULL) ? &nada : result;
 587 }
 588
 589 /*
 590 ** The code below can fail on certain theoretical systems;
 591 ** it works on all known real-world systems as of 2004-12-30.
 592 */
 593
 594 static const char *
 595 tformat(void)
 596 {
 597         if (0.5 == (time_t) 0.5) {      /* floating */
 598                 if (sizeof (time_t) > sizeof (double))
 599                         return "%Lg";
 600                 return "%g";
 601         }
 602         if (0 > (time_t) -1) {          /* signed */
 603                 if (sizeof (time_t) > sizeof (long))
 604                         return "%lld";
 605                 if (sizeof (time_t) > sizeof (int))
 606                         return "%ld";
 607                 return "%d";
 608         }
 609         if (sizeof (time_t) > sizeof (unsigned long))
 610                 return "%llu";
 611         if (sizeof (time_t) > sizeof (unsigned int))
 612                 return "%lu";
 613         return "%u";
 614 }
 615
 616 static void
 617 dumptime(timeptr)
 618 register const struct tm *      timeptr;
 619 {
 620         static const char       wday_name[][3] = {
 621                 "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
 622         };
 623         static const char       mon_name[][3] = {
 624                 "Jan", "Feb", "Mar", "Apr", "May", "Jun",
 625                 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
 626         };
 627         register const char *   wn;
 628         register const char *   mn;
 629         register int            lead;
 630         register int            trail;
 631
 632         if (timeptr == NULL) {
 633                 (void) printf("NULL");
 634                 return;
 635         }
 636         /*
 637         ** The packaged versions of localtime and gmtime never put out-of-range
 638         ** values in tm_wday or tm_mon, but since this code might be compiled
 639         ** with other (perhaps experimental) versions, paranoia is in order.
 640         */
 641         if (timeptr->tm_wday < 0 || timeptr->tm_wday >=
 642                 (int) (sizeof wday_name / sizeof wday_name[0]))
 643                         wn = "???";
 644         else            wn = wday_name[timeptr->tm_wday];
 645         if (timeptr->tm_mon < 0 || timeptr->tm_mon >=
 646                 (int) (sizeof mon_name / sizeof mon_name[0]))
 647                         mn = "???";
 648         else            mn = mon_name[timeptr->tm_mon];
 649         (void) printf("%.3s %.3s%3d %.2d:%.2d:%.2d ",
 650                 wn, mn,
 651                 timeptr->tm_mday, timeptr->tm_hour,
 652                 timeptr->tm_min, timeptr->tm_sec);
 653 #define DIVISOR 10
 654         trail = timeptr->tm_year % DIVISOR + TM_YEAR_BASE % DIVISOR;
 655         lead = timeptr->tm_year / DIVISOR + TM_YEAR_BASE / DIVISOR +
 656                 trail / DIVISOR;
 657         trail %= DIVISOR;
 658         if (trail < 0 && lead > 0) {
 659                 trail += DIVISOR;
 660                 --lead;
 661         } else if (lead < 0 && trail > 0) {
 662                 trail -= DIVISOR;
 663                 ++lead;
 664         }
 665         if (lead == 0)
 666                 (void) printf("%d", trail);
 667         else    (void) printf("%d%d", lead, ((trail < 0) ? -trail : trail));
 668 }