zdump.tproj/zdump.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 #if defined(LIBC_SCCS) && !defined(lint)
  26 #if 0
  27 static char     elsieid[] = "@(#)zdump.c        7.24";
  28 #else
  29 static char rcsid[] = "$OpenBSD: zdump.c,v 1.5 1997/01/21 04:52:45 millert Exp $";
  30 #endif
  31 #endif /* LIBC_SCCS and not lint */
  32
  33 /*
  34 ** This code has been made independent of the rest of the time
  35 ** conversion package to increase confidence in the verification it provides.
  36 ** You can use this code to help in verifying other implementations.
  37 */
  38
  39 #include "stdio.h"      /* for stdout, stderr, perror */
  40 #include "string.h"     /* for strcpy */
  41 #include "sys/types.h"  /* for time_t */
  42 #include "time.h"       /* for struct tm */
  43 #include "stdlib.h"     /* for exit, malloc, atoi */
  44
  45 #ifndef MAX_STRING_LENGTH
  46 #define MAX_STRING_LENGTH       1024
  47 #endif /* !defined MAX_STRING_LENGTH */
  48
  49 #ifndef TRUE
  50 #define TRUE            1
  51 #endif /* !defined TRUE */
  52
  53 #ifndef FALSE
  54 #define FALSE           0
  55 #endif /* !defined FALSE */
  56
  57 #ifndef EXIT_SUCCESS
  58 #define EXIT_SUCCESS    0
  59 #endif /* !defined EXIT_SUCCESS */
  60
  61 #ifndef EXIT_FAILURE
  62 #define EXIT_FAILURE    1
  63 #endif /* !defined EXIT_FAILURE */
  64
  65 #ifndef SECSPERMIN
  66 #define SECSPERMIN      60
  67 #endif /* !defined SECSPERMIN */
  68
  69 #ifndef MINSPERHOUR
  70 #define MINSPERHOUR     60
  71 #endif /* !defined MINSPERHOUR */
  72
  73 #ifndef SECSPERHOUR
  74 #define SECSPERHOUR     (SECSPERMIN * MINSPERHOUR)
  75 #endif /* !defined SECSPERHOUR */
  76
  77 #ifndef HOURSPERDAY
  78 #define HOURSPERDAY     24
  79 #endif /* !defined HOURSPERDAY */
  80
  81 #ifndef EPOCH_YEAR
  82 #define EPOCH_YEAR      1970
  83 #endif /* !defined EPOCH_YEAR */
  84
  85 #ifndef TM_YEAR_BASE
  86 #define TM_YEAR_BASE    1900
  87 #endif /* !defined TM_YEAR_BASE */
  88
  89 #ifndef DAYSPERNYEAR
  90 #define DAYSPERNYEAR    365
  91 #endif /* !defined DAYSPERNYEAR */
  92
  93 #ifndef isleap
  94 #define isleap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
  95 #endif /* !defined isleap */
  96
  97 #if HAVE_GETTEXT - 0
  98 #include "locale.h"     /* for setlocale */
  99 #include "libintl.h"
 100 #endif /* HAVE_GETTEXT - 0 */
 101
 102 #ifndef GNUC_or_lint
 103 #ifdef lint
 104 #define GNUC_or_lint
 105 #endif /* defined lint */
 106 #ifndef lint
 107 #ifdef __GNUC__
 108 #define GNUC_or_lint
 109 #endif /* defined __GNUC__ */
 110 #endif /* !defined lint */
 111 #endif /* !defined GNUC_or_lint */
 112
 113 #ifndef INITIALIZE
 114 #ifdef GNUC_or_lint
 115 #define INITIALIZE(x)   ((x) = 0)
 116 #endif /* defined GNUC_or_lint */
 117 #ifndef GNUC_or_lint
 118 #define INITIALIZE(x)
 119 #endif /* !defined GNUC_or_lint */
 120 #endif /* !defined INITIALIZE */
 121
 122 /*
 123 ** For the benefit of GNU folk...
 124 ** `_(MSGID)' uses the current locale's message library string for MSGID.
 125 ** The default is to use gettext if available, and use MSGID otherwise.
 126 */
 127
 128 #ifndef _
 129 #if HAVE_GETTEXT - 0
 130 #define _(msgid) gettext(msgid)
 131 #else /* !(HAVE_GETTEXT - 0) */
 132 #define _(msgid) msgid
 133 #endif /* !(HAVE_GETTEXT - 0) */
 134 #endif /* !defined _ */
 135
 136 #ifndef TZ_DOMAIN
 137 #define TZ_DOMAIN "tz"
 138 #endif /* !defined TZ_DOMAIN */
 139
 140 extern char **  environ;
 141 extern int      getopt();
 142 extern char *   optarg;
 143 extern int      optind;
 144 extern time_t   time();
 145 extern char *   tzname[2];
 146
 147 static char *   abbr();
 148 static long     delta();
 149 static time_t   hunt();
 150 static int      longest;
 151 static char *   progname;
 152 static void     show();
 153
 154 int
 155 main(argc, argv)
 156 int     argc;
 157 char *  argv[];
 158 {
 159         register int            i;
 160         register int            c;
 161         register int            vflag;
 162         register char *         cutoff;
 163         register int            cutyear;
 164         register long           cuttime;
 165         char **                 fakeenv;
 166         time_t                  now;
 167         time_t                  t;
 168         time_t                  newt;
 169         time_t                  hibit;
 170         struct tm               tm;
 171         struct tm               newtm;
 172
 173         INITIALIZE(cuttime);
 174 #if HAVE_GETTEXT - 0
 175         (void) setlocale(LC_MESSAGES, "");
 176 #ifdef TZ_DOMAINDIR
 177         (void) bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR);
 178 #endif /* defined(TEXTDOMAINDIR) */
 179         (void) textdomain(TZ_DOMAIN);
 180 #endif /* HAVE_GETTEXT - 0 */
 181         progname = argv[0];
 182         vflag = 0;
 183         cutoff = NULL;
 184         while ((c = getopt(argc, argv, "c:v")) == 'c' || c == 'v')
 185                 if (c == 'v')
 186                         vflag = 1;
 187                 else    cutoff = optarg;
 188         if (c != EOF ||
 189                 (optind == argc - 1 && strcmp(argv[optind], "=") == 0)) {
 190                         (void) fprintf(stderr,
 191 _("%s: usage is %s [ -v ] [ -c cutoff ] zonename ...\n"),
 192                                 argv[0], argv[0]);
 193                         (void) exit(EXIT_FAILURE);
 194         }
 195         if (cutoff != NULL) {
 196                 int     y;
 197
 198                 cutyear = atoi(cutoff);
 199                 cuttime = 0;
 200                 for (y = EPOCH_YEAR; y < cutyear; ++y)
 201                         cuttime += DAYSPERNYEAR + isleap(y);
 202                 cuttime *= SECSPERHOUR * HOURSPERDAY;
 203         }
 204         (void) time(&now);
 205         longest = 0;
 206         for (i = optind; i < argc; ++i)
 207                 if (strlen(argv[i]) > longest)
 208                         longest = strlen(argv[i]);
 209         for (hibit = 1; (hibit << 1) != 0; hibit <<= 1)
 210                 continue;
 211         {
 212                 register int    from;
 213                 register int    to;
 214
 215                 for (i = 0;  environ[i] != NULL;  ++i)
 216                         continue;
 217                 fakeenv = (char **) malloc((size_t) ((i + 2) *
 218                         sizeof *fakeenv));
 219                 if (fakeenv == NULL ||
 220                         (fakeenv[0] = (char *) malloc((size_t) (longest +
 221                                 4))) == NULL) {
 222                                         (void) perror(progname);
 223                                         (void) exit(EXIT_FAILURE);
 224                 }
 225                 to = 0;
 226                 (void) strcpy(fakeenv[to++], "TZ=");
 227                 for (from = 0; environ[from] != NULL; ++from)
 228                         if (strncmp(environ[from], "TZ=", 3) != 0)
 229                                 fakeenv[to++] = environ[from];
 230                 fakeenv[to] = NULL;
 231                 environ = fakeenv;
 232         }
 233         for (i = optind; i < argc; ++i) {
 234                 static char     buf[MAX_STRING_LENGTH];
 235
 236                 (void) strcpy(&fakeenv[0][3], argv[i]);
 237                 show(argv[i], now, FALSE);
 238                 if (!vflag)
 239                         continue;
 240                 /*
 241                 ** Get lowest value of t.
 242                 */
 243                 t = hibit;
 244                 if (t > 0)              /* time_t is unsigned */
 245                         t = 0;
 246                 show(argv[i], t, TRUE);
 247                 t += SECSPERHOUR * HOURSPERDAY;
 248                 show(argv[i], t, TRUE);
 249                 tm = *localtime(&t);
 250                 (void) strncpy(buf, abbr(&tm), (sizeof buf) - 1);
 251                 for ( ; ; ) {
 252                         if (cutoff != NULL && t >= cuttime)
 253                                 break;
 254                         newt = t + SECSPERHOUR * 12;
 255                         if (cutoff != NULL && newt >= cuttime)
 256                                 break;
 257                         if (newt <= t)
 258                                 break;
 259                         newtm = *localtime(&newt);
 260                         if (delta(&newtm, &tm) != (newt - t) ||
 261                                 newtm.tm_isdst != tm.tm_isdst ||
 262                                 strcmp(abbr(&newtm), buf) != 0) {
 263                                         newt = hunt(argv[i], t, newt);
 264                                         newtm = *localtime(&newt);
 265                                         (void) strncpy(buf, abbr(&newtm),
 266                                                 (sizeof buf) - 1);
 267                         }
 268                         t = newt;
 269                         tm = newtm;
 270                 }
 271                 /*
 272                 ** Get highest value of t.
 273                 */
 274                 t = ~((time_t) 0);
 275                 if (t < 0)              /* time_t is signed */
 276                         t &= ~hibit;
 277                 t -= SECSPERHOUR * HOURSPERDAY;
 278                 show(argv[i], t, TRUE);
 279                 t += SECSPERHOUR * HOURSPERDAY;
 280                 show(argv[i], t, TRUE);
 281         }
 282         if (fflush(stdout) || ferror(stdout)) {
 283                 (void) fprintf(stderr, _("%s: Error writing standard output "),
 284                         argv[0]);
 285                 (void) perror(_("standard output"));
 286                 (void) exit(EXIT_FAILURE);
 287         }
 288         exit(EXIT_SUCCESS);
 289
 290         /* gcc -Wall pacifier */
 291         for ( ; ; )
 292                 continue;
 293 }
 294
 295 static time_t
 296 hunt(name, lot, hit)
 297 char *  name;
 298 time_t  lot;
 299 time_t  hit;
 300 {
 301         time_t          t;
 302         struct tm       lotm;
 303         struct tm       tm;
 304         static char     loab[MAX_STRING_LENGTH];
 305
 306         lotm = *localtime(&lot);
 307         (void) strncpy(loab, abbr(&lotm), (sizeof loab) - 1);
 308         loab[(sizeof loab) - 1] = '\0';
 309         while ((hit - lot) >= 2) {
 310                 t = lot / 2 + hit / 2;
 311                 if (t <= lot)
 312                         ++t;
 313                 else if (t >= hit)
 314                         --t;
 315                 tm = *localtime(&t);
 316                 if (delta(&tm, &lotm) == (t - lot) &&
 317                         tm.tm_isdst == lotm.tm_isdst &&
 318                         strcmp(abbr(&tm), loab) == 0) {
 319                                 lot = t;
 320                                 lotm = tm;
 321                 } else  hit = t;
 322         }
 323         show(name, lot, TRUE);
 324         show(name, hit, TRUE);
 325         return hit;
 326 }
 327
 328 /*
 329 ** Thanks to Paul Eggert (eggert@twinsun.com) for logic used in delta.
 330 */
 331
 332 static long
 333 delta(newp, oldp)
 334 struct tm *     newp;
 335 struct tm *     oldp;
 336 {
 337         long    result;
 338         int     tmy;
 339
 340         if (newp->tm_year < oldp->tm_year)
 341                 return -delta(oldp, newp);
 342         result = 0;
 343         for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy)
 344                 result += DAYSPERNYEAR + isleap(tmy + TM_YEAR_BASE);
 345         result += newp->tm_yday - oldp->tm_yday;
 346         result *= HOURSPERDAY;
 347         result += newp->tm_hour - oldp->tm_hour;
 348         result *= MINSPERHOUR;
 349         result += newp->tm_min - oldp->tm_min;
 350         result *= SECSPERMIN;
 351         result += newp->tm_sec - oldp->tm_sec;
 352         return result;
 353 }
 354
 355 extern struct tm *      localtime();
 356
 357 static void
 358 show(zone, t, v)
 359 char *  zone;
 360 time_t  t;
 361 int     v;
 362 {
 363         struct tm *     tmp;
 364
 365         (void) printf("%-*s  ", longest, zone);
 366         if (v)
 367                 (void) printf("%.24s GMT = ", asctime(gmtime(&t)));
 368         tmp = localtime(&t);
 369         (void) printf("%.24s", asctime(tmp));
 370         if (*abbr(tmp) != '\0')
 371                 (void) printf(" %s", abbr(tmp));
 372         if (v) {
 373                 (void) printf(" isdst=%d", tmp->tm_isdst);
 374 #ifdef TM_GMTOFF
 375                 (void) printf(" gmtoff=%ld", tmp->TM_GMTOFF);
 376 #endif /* defined TM_GMTOFF */
 377         }
 378         (void) printf("\n");
 379 }
 380
 381 static char *
 382 abbr(tmp)
 383 struct tm *     tmp;
 384 {
 385         register char * result;
 386         static char     nada;
 387
 388         if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1)
 389                 return &nada;
 390         result = tzname[tmp->tm_isdst];
 391         return (result == NULL) ? &nada : result;
 392 }