zdump.tproj/zdump.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * "Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.0 (the 'License').  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License."
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 #if defined(LIBC_SCCS) && !defined(lint)
  25 #if 0
  26 static char     elsieid[] = "@(#)zdump.c        7.24";
  27 #else
  28 static char rcsid[] = "$OpenBSD: zdump.c,v 1.5 1997/01/21 04:52:45 millert Exp $";
  29 #endif
  30 #endif /* LIBC_SCCS and not lint */
  31
  32 /*
  33 ** This code has been made independent of the rest of the time
  34 ** conversion package to increase confidence in the verification it provides.
  35 ** You can use this code to help in verifying other implementations.
  36 */
  37
  38 #include "stdio.h"      /* for stdout, stderr, perror */
  39 #include "string.h"     /* for strcpy */
  40 #include "sys/types.h"  /* for time_t */
  41 #include "time.h"       /* for struct tm */
  42 #include "stdlib.h"     /* for exit, malloc, atoi */
  43
  44 #ifndef MAX_STRING_LENGTH
  45 #define MAX_STRING_LENGTH       1024
  46 #endif /* !defined MAX_STRING_LENGTH */
  47
  48 #ifndef TRUE
  49 #define TRUE            1
  50 #endif /* !defined TRUE */
  51
  52 #ifndef FALSE
  53 #define FALSE           0
  54 #endif /* !defined FALSE */
  55
  56 #ifndef EXIT_SUCCESS
  57 #define EXIT_SUCCESS    0
  58 #endif /* !defined EXIT_SUCCESS */
  59
  60 #ifndef EXIT_FAILURE
  61 #define EXIT_FAILURE    1
  62 #endif /* !defined EXIT_FAILURE */
  63
  64 #ifndef SECSPERMIN
  65 #define SECSPERMIN      60
  66 #endif /* !defined SECSPERMIN */
  67
  68 #ifndef MINSPERHOUR
  69 #define MINSPERHOUR     60
  70 #endif /* !defined MINSPERHOUR */
  71
  72 #ifndef SECSPERHOUR
  73 #define SECSPERHOUR     (SECSPERMIN * MINSPERHOUR)
  74 #endif /* !defined SECSPERHOUR */
  75
  76 #ifndef HOURSPERDAY
  77 #define HOURSPERDAY     24
  78 #endif /* !defined HOURSPERDAY */
  79
  80 #ifndef EPOCH_YEAR
  81 #define EPOCH_YEAR      1970
  82 #endif /* !defined EPOCH_YEAR */
  83
  84 #ifndef TM_YEAR_BASE
  85 #define TM_YEAR_BASE    1900
  86 #endif /* !defined TM_YEAR_BASE */
  87
  88 #ifndef DAYSPERNYEAR
  89 #define DAYSPERNYEAR    365
  90 #endif /* !defined DAYSPERNYEAR */
  91
  92 #ifndef isleap
  93 #define isleap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
  94 #endif /* !defined isleap */
  95
  96 #if HAVE_GETTEXT - 0
  97 #include "locale.h"     /* for setlocale */
  98 #include "libintl.h"
  99 #endif /* HAVE_GETTEXT - 0 */
 100
 101 #ifndef GNUC_or_lint
 102 #ifdef lint
 103 #define GNUC_or_lint
 104 #endif /* defined lint */
 105 #ifndef lint
 106 #ifdef __GNUC__
 107 #define GNUC_or_lint
 108 #endif /* defined __GNUC__ */
 109 #endif /* !defined lint */
 110 #endif /* !defined GNUC_or_lint */
 111
 112 #ifndef INITIALIZE
 113 #ifdef GNUC_or_lint
 114 #define INITIALIZE(x)   ((x) = 0)
 115 #endif /* defined GNUC_or_lint */
 116 #ifndef GNUC_or_lint
 117 #define INITIALIZE(x)
 118 #endif /* !defined GNUC_or_lint */
 119 #endif /* !defined INITIALIZE */
 120
 121 /*
 122 ** For the benefit of GNU folk...
 123 ** `_(MSGID)' uses the current locale's message library string for MSGID.
 124 ** The default is to use gettext if available, and use MSGID otherwise.
 125 */
 126
 127 #ifndef _
 128 #if HAVE_GETTEXT - 0
 129 #define _(msgid) gettext(msgid)
 130 #else /* !(HAVE_GETTEXT - 0) */
 131 #define _(msgid) msgid
 132 #endif /* !(HAVE_GETTEXT - 0) */
 133 #endif /* !defined _ */
 134
 135 #ifndef TZ_DOMAIN
 136 #define TZ_DOMAIN "tz"
 137 #endif /* !defined TZ_DOMAIN */
 138
 139 extern char **  environ;
 140 extern int      getopt();
 141 extern char *   optarg;
 142 extern int      optind;
 143 extern time_t   time();
 144 extern char *   tzname[2];
 145
 146 static char *   abbr();
 147 static long     delta();
 148 static time_t   hunt();
 149 static int      longest;
 150 static char *   progname;
 151 static void     show();
 152
 153 int
 154 main(argc, argv)
 155 int     argc;
 156 char *  argv[];
 157 {
 158         register int            i;
 159         register int            c;
 160         register int            vflag;
 161         register char *         cutoff;
 162         register int            cutyear;
 163         register long           cuttime;
 164         char **                 fakeenv;
 165         time_t                  now;
 166         time_t                  t;
 167         time_t                  newt;
 168         time_t                  hibit;
 169         struct tm               tm;
 170         struct tm               newtm;
 171
 172         INITIALIZE(cuttime);
 173 #if HAVE_GETTEXT - 0
 174         (void) setlocale(LC_MESSAGES, "");
 175 #ifdef TZ_DOMAINDIR
 176         (void) bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR);
 177 #endif /* defined(TEXTDOMAINDIR) */
 178         (void) textdomain(TZ_DOMAIN);
 179 #endif /* HAVE_GETTEXT - 0 */
 180         progname = argv[0];
 181         vflag = 0;
 182         cutoff = NULL;
 183         while ((c = getopt(argc, argv, "c:v")) == 'c' || c == 'v')
 184                 if (c == 'v')
 185                         vflag = 1;
 186                 else    cutoff = optarg;
 187         if (c != EOF ||
 188                 (optind == argc - 1 && strcmp(argv[optind], "=") == 0)) {
 189                         (void) fprintf(stderr,
 190 _("%s: usage is %s [ -v ] [ -c cutoff ] zonename ...\n"),
 191                                 argv[0], argv[0]);
 192                         (void) exit(EXIT_FAILURE);
 193         }
 194         if (cutoff != NULL) {
 195                 int     y;
 196
 197                 cutyear = atoi(cutoff);
 198                 cuttime = 0;
 199                 for (y = EPOCH_YEAR; y < cutyear; ++y)
 200                         cuttime += DAYSPERNYEAR + isleap(y);
 201                 cuttime *= SECSPERHOUR * HOURSPERDAY;
 202         }
 203         (void) time(&now);
 204         longest = 0;
 205         for (i = optind; i < argc; ++i)
 206                 if (strlen(argv[i]) > longest)
 207                         longest = strlen(argv[i]);
 208         for (hibit = 1; (hibit << 1) != 0; hibit <<= 1)
 209                 continue;
 210         {
 211                 register int    from;
 212                 register int    to;
 213
 214                 for (i = 0;  environ[i] != NULL;  ++i)
 215                         continue;
 216                 fakeenv = (char **) malloc((size_t) ((i + 2) *
 217                         sizeof *fakeenv));
 218                 if (fakeenv == NULL ||
 219                         (fakeenv[0] = (char *) malloc((size_t) (longest +
 220                                 4))) == NULL) {
 221                                         (void) perror(progname);
 222                                         (void) exit(EXIT_FAILURE);
 223                 }
 224                 to = 0;
 225                 (void) strcpy(fakeenv[to++], "TZ=");
 226                 for (from = 0; environ[from] != NULL; ++from)
 227                         if (strncmp(environ[from], "TZ=", 3) != 0)
 228                                 fakeenv[to++] = environ[from];
 229                 fakeenv[to] = NULL;
 230                 environ = fakeenv;
 231         }
 232         for (i = optind; i < argc; ++i) {
 233                 static char     buf[MAX_STRING_LENGTH];
 234
 235                 (void) strcpy(&fakeenv[0][3], argv[i]);
 236                 show(argv[i], now, FALSE);
 237                 if (!vflag)
 238                         continue;
 239                 /*
 240                 ** Get lowest value of t.
 241                 */
 242                 t = hibit;
 243                 if (t > 0)              /* time_t is unsigned */
 244                         t = 0;
 245                 show(argv[i], t, TRUE);
 246                 t += SECSPERHOUR * HOURSPERDAY;
 247                 show(argv[i], t, TRUE);
 248                 tm = *localtime(&t);
 249                 (void) strncpy(buf, abbr(&tm), (sizeof buf) - 1);
 250                 for ( ; ; ) {
 251                         if (cutoff != NULL && t >= cuttime)
 252                                 break;
 253                         newt = t + SECSPERHOUR * 12;
 254                         if (cutoff != NULL && newt >= cuttime)
 255                                 break;
 256                         if (newt <= t)
 257                                 break;
 258                         newtm = *localtime(&newt);
 259                         if (delta(&newtm, &tm) != (newt - t) ||
 260                                 newtm.tm_isdst != tm.tm_isdst ||
 261                                 strcmp(abbr(&newtm), buf) != 0) {
 262                                         newt = hunt(argv[i], t, newt);
 263                                         newtm = *localtime(&newt);
 264                                         (void) strncpy(buf, abbr(&newtm),
 265                                                 (sizeof buf) - 1);
 266                         }
 267                         t = newt;
 268                         tm = newtm;
 269                 }
 270                 /*
 271                 ** Get highest value of t.
 272                 */
 273                 t = ~((time_t) 0);
 274                 if (t < 0)              /* time_t is signed */
 275                         t &= ~hibit;
 276                 t -= SECSPERHOUR * HOURSPERDAY;
 277                 show(argv[i], t, TRUE);
 278                 t += SECSPERHOUR * HOURSPERDAY;
 279                 show(argv[i], t, TRUE);
 280         }
 281         if (fflush(stdout) || ferror(stdout)) {
 282                 (void) fprintf(stderr, _("%s: Error writing standard output "),
 283                         argv[0]);
 284                 (void) perror(_("standard output"));
 285                 (void) exit(EXIT_FAILURE);
 286         }
 287         exit(EXIT_SUCCESS);
 288
 289         /* gcc -Wall pacifier */
 290         for ( ; ; )
 291                 continue;
 292 }
 293
 294 static time_t
 295 hunt(name, lot, hit)
 296 char *  name;
 297 time_t  lot;
 298 time_t  hit;
 299 {
 300         time_t          t;
 301         struct tm       lotm;
 302         struct tm       tm;
 303         static char     loab[MAX_STRING_LENGTH];
 304
 305         lotm = *localtime(&lot);
 306         (void) strncpy(loab, abbr(&lotm), (sizeof loab) - 1);
 307         loab[(sizeof loab) - 1] = '\0';
 308         while ((hit - lot) >= 2) {
 309                 t = lot / 2 + hit / 2;
 310                 if (t <= lot)
 311                         ++t;
 312                 else if (t >= hit)
 313                         --t;
 314                 tm = *localtime(&t);
 315                 if (delta(&tm, &lotm) == (t - lot) &&
 316                         tm.tm_isdst == lotm.tm_isdst &&
 317                         strcmp(abbr(&tm), loab) == 0) {
 318                                 lot = t;
 319                                 lotm = tm;
 320                 } else  hit = t;
 321         }
 322         show(name, lot, TRUE);
 323         show(name, hit, TRUE);
 324         return hit;
 325 }
 326
 327 /*
 328 ** Thanks to Paul Eggert (eggert@twinsun.com) for logic used in delta.
 329 */
 330
 331 static long
 332 delta(newp, oldp)
 333 struct tm *     newp;
 334 struct tm *     oldp;
 335 {
 336         long    result;
 337         int     tmy;
 338
 339         if (newp->tm_year < oldp->tm_year)
 340                 return -delta(oldp, newp);
 341         result = 0;
 342         for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy)
 343                 result += DAYSPERNYEAR + isleap(tmy + TM_YEAR_BASE);
 344         result += newp->tm_yday - oldp->tm_yday;
 345         result *= HOURSPERDAY;
 346         result += newp->tm_hour - oldp->tm_hour;
 347         result *= MINSPERHOUR;
 348         result += newp->tm_min - oldp->tm_min;
 349         result *= SECSPERMIN;
 350         result += newp->tm_sec - oldp->tm_sec;
 351         return result;
 352 }
 353
 354 extern struct tm *      localtime();
 355
 356 static void
 357 show(zone, t, v)
 358 char *  zone;
 359 time_t  t;
 360 int     v;
 361 {
 362         struct tm *     tmp;
 363
 364         (void) printf("%-*s  ", longest, zone);
 365         if (v)
 366                 (void) printf("%.24s GMT = ", asctime(gmtime(&t)));
 367         tmp = localtime(&t);
 368         (void) printf("%.24s", asctime(tmp));
 369         if (*abbr(tmp) != '\0')
 370                 (void) printf(" %s", abbr(tmp));
 371         if (v) {
 372                 (void) printf(" isdst=%d", tmp->tm_isdst);
 373 #ifdef TM_GMTOFF
 374                 (void) printf(" gmtoff=%ld", tmp->TM_GMTOFF);
 375 #endif /* defined TM_GMTOFF */
 376         }
 377         (void) printf("\n");
 378 }
 379
 380 static char *
 381 abbr(tmp)
 382 struct tm *     tmp;
 383 {
 384         register char * result;
 385         static char     nada;
 386
 387         if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1)
 388                 return &nada;
 389         result = tzname[tmp->tm_isdst];
 390         return (result == NULL) ? &nada : result;
 391 }