1 /* $NetBSD: zdump.c,v 1.13 2002/05/26 11:49:58 wiz Exp $ */ 2 3 #include <sys/cdefs.h> 4 #ifndef lint 5 #ifndef NOID 6 #if 0 7 static char elsieid[] = "@(#)zdump.c 7.29"; 8 #else 9 __RCSID("$NetBSD: zdump.c,v 1.13 2002/05/26 11:49:58 wiz Exp $"); 10 #endif 11 #endif /* !defined NOID */ 12 #endif /* !defined lint */ 13 14 /* 15 ** This code has been made independent of the rest of the time 16 ** conversion package to increase confidence in the verification it provides. 17 ** You can use this code to help in verifying other implementations. 18 */ 19 20 #include "stdio.h" /* for stdout, stderr, perror */ 21 #include "string.h" /* for strcpy */ 22 #include "sys/types.h" /* for time_t */ 23 #include "time.h" /* for struct tm */ 24 #include "stdlib.h" /* for exit, malloc, atoi */ 25 26 #ifndef MAX_STRING_LENGTH 27 #define MAX_STRING_LENGTH 1024 28 #endif /* !defined MAX_STRING_LENGTH */ 29 30 #ifndef TRUE 31 #define TRUE 1 32 #endif /* !defined TRUE */ 33 34 #ifndef FALSE 35 #define FALSE 0 36 #endif /* !defined FALSE */ 37 38 #ifndef EXIT_SUCCESS 39 #define EXIT_SUCCESS 0 40 #endif /* !defined EXIT_SUCCESS */ 41 42 #ifndef EXIT_FAILURE 43 #define EXIT_FAILURE 1 44 #endif /* !defined EXIT_FAILURE */ 45 46 #ifndef SECSPERMIN 47 #define SECSPERMIN 60 48 #endif /* !defined SECSPERMIN */ 49 50 #ifndef MINSPERHOUR 51 #define MINSPERHOUR 60 52 #endif /* !defined MINSPERHOUR */ 53 54 #ifndef SECSPERHOUR 55 #define SECSPERHOUR (SECSPERMIN * MINSPERHOUR) 56 #endif /* !defined SECSPERHOUR */ 57 58 #ifndef HOURSPERDAY 59 #define HOURSPERDAY 24 60 #endif /* !defined HOURSPERDAY */ 61 62 #ifndef EPOCH_YEAR 63 #define EPOCH_YEAR 1970 64 #endif /* !defined EPOCH_YEAR */ 65 66 #ifndef TM_YEAR_BASE 67 #define TM_YEAR_BASE 1900 68 #endif /* !defined TM_YEAR_BASE */ 69 70 #ifndef DAYSPERNYEAR 71 #define DAYSPERNYEAR 365 72 #endif /* !defined DAYSPERNYEAR */ 73 74 #ifndef isleap 75 #define isleap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0) 76 #endif /* !defined isleap */ 77 78 #if HAVE_GETTEXT - 0 79 #include "locale.h" /* for setlocale */ 80 #include "libintl.h" 81 #endif /* HAVE_GETTEXT - 0 */ 82 83 #ifndef GNUC_or_lint 84 #ifdef lint 85 #define GNUC_or_lint 86 #endif /* defined lint */ 87 #ifndef lint 88 #ifdef __GNUC__ 89 #define GNUC_or_lint 90 #endif /* defined __GNUC__ */ 91 #endif /* !defined lint */ 92 #endif /* !defined GNUC_or_lint */ 93 94 #ifndef INITIALIZE 95 #ifdef GNUC_or_lint 96 #define INITIALIZE(x) ((x) = 0) 97 #endif /* defined GNUC_or_lint */ 98 #ifndef GNUC_or_lint 99 #define INITIALIZE(x) 100 #endif /* !defined GNUC_or_lint */ 101 #endif /* !defined INITIALIZE */ 102 103 /* 104 ** For the benefit of GNU folk... 105 ** `_(MSGID)' uses the current locale's message library string for MSGID. 106 ** The default is to use gettext if available, and use MSGID otherwise. 107 */ 108 109 #ifndef _ 110 #if HAVE_GETTEXT - 0 111 #define _(msgid) gettext(msgid) 112 #else /* !(HAVE_GETTEXT - 0) */ 113 #define _(msgid) msgid 114 #endif /* !(HAVE_GETTEXT - 0) */ 115 #endif /* !defined _ */ 116 117 #ifndef TZ_DOMAIN 118 #define TZ_DOMAIN "tz" 119 #endif /* !defined TZ_DOMAIN */ 120 121 #ifndef P 122 #define P(x) x 123 #endif /* !defined P */ 124 125 extern char ** environ; 126 extern int getopt P((int argc, char * const argv[], 127 const char * options)); 128 extern char * optarg; 129 extern int optind; 130 131 static const char * abbr P((struct tm * tmp)); 132 static long delta P((struct tm * newp, struct tm * oldp)); 133 static time_t hunt P((char * name, time_t lot, time_t hit)); 134 int main P((int, char **)); 135 static size_t longest; 136 static char * progname; 137 static void show P((char * zone, time_t t, int v)); 138 139 int 140 main(argc, argv) 141 int argc; 142 char * argv[]; 143 { 144 register int i; 145 register int c; 146 register int vflag; 147 register char * cutoff; 148 register int cutyear; 149 register long cuttime; 150 char ** fakeenv; 151 time_t now; 152 time_t t; 153 time_t newt; 154 time_t hibit; 155 struct tm tm; 156 struct tm newtm; 157 158 INITIALIZE(cuttime); 159 #if HAVE_GETTEXT - 0 160 (void) setlocale(LC_MESSAGES, ""); 161 #ifdef TZ_DOMAINDIR 162 (void) bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR); 163 #endif /* defined(TEXTDOMAINDIR) */ 164 (void) textdomain(TZ_DOMAIN); 165 #endif /* HAVE_GETTEXT - 0 */ 166 progname = argv[0]; 167 vflag = 0; 168 cutoff = NULL; 169 while ((c = getopt(argc, argv, "c:v")) == 'c' || c == 'v') 170 if (c == 'v') 171 vflag = 1; 172 else cutoff = optarg; 173 if ((c != EOF && c != -1) || 174 (optind == argc - 1 && strcmp(argv[optind], "=") == 0)) { 175 (void) fprintf(stderr, 176 _("%s: usage is %s [ -v ] [ -c cutoff ] zonename ...\n"), 177 argv[0], argv[0]); 178 (void) exit(EXIT_FAILURE); 179 } 180 if (cutoff != NULL) { 181 int y; 182 183 cutyear = atoi(cutoff); 184 cuttime = 0; 185 for (y = EPOCH_YEAR; y < cutyear; ++y) 186 cuttime += DAYSPERNYEAR + isleap(y); 187 cuttime *= SECSPERHOUR * HOURSPERDAY; 188 } 189 (void) time(&now); 190 longest = 0; 191 for (i = optind; i < argc; ++i) 192 if (strlen(argv[i]) > longest) 193 longest = strlen(argv[i]); 194 for (hibit = 1; (hibit << 1) != 0; hibit <<= 1) 195 continue; 196 { 197 register int from; 198 register int to; 199 200 for (i = 0; environ[i] != NULL; ++i) 201 continue; 202 fakeenv = (char **) malloc((size_t) ((i + 2) * 203 sizeof *fakeenv)); 204 if (fakeenv == NULL || 205 (fakeenv[0] = (char *) malloc(longest + 4)) == NULL) { 206 (void) perror(progname); 207 (void) exit(EXIT_FAILURE); 208 } 209 to = 0; 210 (void)strcpy(fakeenv[to++], "TZ="); /* XXX strcpy is safe */ 211 for (from = 0; environ[from] != NULL; ++from) 212 if (strncmp(environ[from], "TZ=", 3) != 0) 213 fakeenv[to++] = environ[from]; 214 fakeenv[to] = NULL; 215 environ = fakeenv; 216 } 217 for (i = optind; i < argc; ++i) { 218 static char buf[MAX_STRING_LENGTH]; 219 220 (void) strcpy(&fakeenv[0][3], argv[i]); /* XXX strcpy is safe */ 221 if (!vflag) { 222 show(argv[i], now, FALSE); 223 continue; 224 } 225 /* 226 ** Get lowest value of t. 227 */ 228 t = hibit; 229 if (t > 0) /* time_t is unsigned */ 230 t = 0; 231 show(argv[i], t, TRUE); 232 t += SECSPERHOUR * HOURSPERDAY; 233 show(argv[i], t, TRUE); 234 tm = *localtime(&t); 235 (void) strlcpy(buf, abbr(&tm), (sizeof buf)); 236 for ( ; ; ) { 237 if (cutoff != NULL && t >= cuttime) 238 break; 239 newt = t + SECSPERHOUR * 12; 240 if (cutoff != NULL && newt >= cuttime) 241 break; 242 if (newt <= t) 243 break; 244 newtm = *localtime(&newt); 245 if (delta(&newtm, &tm) != (newt - t) || 246 newtm.tm_isdst != tm.tm_isdst || 247 strcmp(abbr(&newtm), buf) != 0) { 248 newt = hunt(argv[i], t, newt); 249 newtm = *localtime(&newt); 250 (void) strlcpy(buf, abbr(&newtm), 251 (sizeof buf)); 252 } 253 t = newt; 254 tm = newtm; 255 } 256 /* 257 ** Get highest value of t. 258 */ 259 t = ~((time_t) 0); 260 if (t < 0) /* time_t is signed */ 261 t &= ~hibit; 262 t -= SECSPERHOUR * HOURSPERDAY; 263 show(argv[i], t, TRUE); 264 t += SECSPERHOUR * HOURSPERDAY; 265 show(argv[i], t, TRUE); 266 } 267 if (fflush(stdout) || ferror(stdout)) { 268 (void) fprintf(stderr, "%s: ", argv[0]); 269 (void) perror(_("Error writing standard output")); 270 (void) exit(EXIT_FAILURE); 271 } 272 exit(EXIT_SUCCESS); 273 274 /* gcc -Wall pacifier */ 275 for ( ; ; ) 276 continue; 277 } 278 279 static time_t 280 hunt(name, lot, hit) 281 char * name; 282 time_t lot; 283 time_t hit; 284 { 285 time_t t; 286 struct tm lotm; 287 struct tm tm; 288 static char loab[MAX_STRING_LENGTH]; 289 290 lotm = *localtime(&lot); 291 (void) strlcpy(loab, abbr(&lotm), (sizeof loab)); 292 while ((hit - lot) >= 2) { 293 t = lot / 2 + hit / 2; 294 if (t <= lot) 295 ++t; 296 else if (t >= hit) 297 --t; 298 tm = *localtime(&t); 299 if (delta(&tm, &lotm) == (t - lot) && 300 tm.tm_isdst == lotm.tm_isdst && 301 strcmp(abbr(&tm), loab) == 0) { 302 lot = t; 303 lotm = tm; 304 } else hit = t; 305 } 306 show(name, lot, TRUE); 307 show(name, hit, TRUE); 308 return hit; 309 } 310 311 /* 312 ** Thanks to Paul Eggert (eggert@twinsun.com) for logic used in delta. 313 */ 314 315 static long 316 delta(newp, oldp) 317 struct tm * newp; 318 struct tm * oldp; 319 { 320 long result; 321 int tmy; 322 323 if (newp->tm_year < oldp->tm_year) 324 return -delta(oldp, newp); 325 result = 0; 326 for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy) 327 result += DAYSPERNYEAR + isleap(tmy + TM_YEAR_BASE); 328 result += newp->tm_yday - oldp->tm_yday; 329 result *= HOURSPERDAY; 330 result += newp->tm_hour - oldp->tm_hour; 331 result *= MINSPERHOUR; 332 result += newp->tm_min - oldp->tm_min; 333 result *= SECSPERMIN; 334 result += newp->tm_sec - oldp->tm_sec; 335 return result; 336 } 337 338 static void 339 show(zone, t, v) 340 char * zone; 341 time_t t; 342 int v; 343 { 344 struct tm * tmp; 345 346 (void) printf("%-*s ", (int) longest, zone); 347 if (v) 348 (void) printf("%.24s UTC = ", asctime(gmtime(&t))); 349 tmp = localtime(&t); 350 (void) printf("%.24s", asctime(tmp)); 351 if (*abbr(tmp) != '\0') 352 (void) printf(" %s", abbr(tmp)); 353 if (v) { 354 (void) printf(" isdst=%d", tmp->tm_isdst); 355 #ifdef TM_GMTOFF 356 (void) printf(" gmtoff=%ld", tmp->TM_GMTOFF); 357 #endif /* defined TM_GMTOFF */ 358 } 359 (void) printf("\n"); 360 } 361 362 static const char * 363 abbr(tmp) 364 struct tm * tmp; 365 { 366 register const char * result; 367 static const char nada; 368 369 if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1) 370 return &nada; 371 result = tzname[tmp->tm_isdst]; 372 return (result == NULL) ? &nada : result; 373 } 374