| 1 | /* |
| 2 | * Copyright (c) 1987 Regents of the University of California. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * This code is derived from software contributed to Berkeley by |
| 6 | * Arthur Olson. |
| 7 | * |
| 8 | * Redistribution and use in source and binary forms are permitted |
| 9 | * provided that the above copyright notice and this paragraph are |
| 10 | * duplicated in all such forms and that any documentation, |
| 11 | * advertising materials, and other materials related to such |
| 12 | * distribution and use acknowledge that the software was developed |
| 13 | * by the University of California, Berkeley. The name of the |
| 14 | * University may not be used to endorse or promote products derived |
| 15 | * from this software without specific prior written permission. |
| 16 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR |
| 17 | * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED |
| 18 | * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| 19 | */ |
| 20 | |
| 21 | #if defined(LIBC_SCCS) && !defined(lint) |
| 22 | static char sccsid[] = "@(#)ctime.c 5.14 (Berkeley) %G%"; |
| 23 | #endif /* LIBC_SCCS and not lint */ |
| 24 | |
| 25 | #include "sys/param.h" |
| 26 | #include "sys/time.h" |
| 27 | #include "tzfile.h" |
| 28 | |
| 29 | char * |
| 30 | ctime(t) |
| 31 | time_t *t; |
| 32 | { |
| 33 | struct tm *localtime(); |
| 34 | char *asctime(); |
| 35 | |
| 36 | return(asctime(localtime(t))); |
| 37 | } |
| 38 | |
| 39 | /* |
| 40 | ** A la X3J11 |
| 41 | */ |
| 42 | |
| 43 | char * |
| 44 | asctime(timeptr) |
| 45 | register struct tm * timeptr; |
| 46 | { |
| 47 | static char wday_name[DAYS_PER_WEEK][3] = { |
| 48 | "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" |
| 49 | }; |
| 50 | static char mon_name[MONS_PER_YEAR][3] = { |
| 51 | "Jan", "Feb", "Mar", "Apr", "May", "Jun", |
| 52 | "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" |
| 53 | }; |
| 54 | static char result[26]; |
| 55 | |
| 56 | (void) sprintf(result, "%.3s %.3s%3d %02d:%02d:%02d %d\n", |
| 57 | wday_name[timeptr->tm_wday], |
| 58 | mon_name[timeptr->tm_mon], |
| 59 | timeptr->tm_mday, timeptr->tm_hour, |
| 60 | timeptr->tm_min, timeptr->tm_sec, |
| 61 | TM_YEAR_BASE + timeptr->tm_year); |
| 62 | return result; |
| 63 | } |
| 64 | |
| 65 | #ifndef TRUE |
| 66 | #define TRUE 1 |
| 67 | #define FALSE 0 |
| 68 | #endif /* !TRUE */ |
| 69 | |
| 70 | extern char * getenv(); |
| 71 | extern char * strcpy(); |
| 72 | extern char * strcat(); |
| 73 | struct tm * offtime(); |
| 74 | |
| 75 | struct ttinfo { /* time type information */ |
| 76 | long tt_gmtoff; /* GMT offset in seconds */ |
| 77 | int tt_isdst; /* used to set tm_isdst */ |
| 78 | int tt_abbrind; /* abbreviation list index */ |
| 79 | }; |
| 80 | |
| 81 | struct state { |
| 82 | int timecnt; |
| 83 | int typecnt; |
| 84 | int charcnt; |
| 85 | time_t ats[TZ_MAX_TIMES]; |
| 86 | unsigned char types[TZ_MAX_TIMES]; |
| 87 | struct ttinfo ttis[TZ_MAX_TYPES]; |
| 88 | char chars[TZ_MAX_CHARS + 1]; |
| 89 | }; |
| 90 | |
| 91 | static struct state s; |
| 92 | |
| 93 | static int tz_is_set; |
| 94 | |
| 95 | char * tzname[2] = { |
| 96 | "GMT", |
| 97 | "GMT" |
| 98 | }; |
| 99 | |
| 100 | #ifdef USG_COMPAT |
| 101 | time_t timezone = 0; |
| 102 | int daylight = 0; |
| 103 | #endif /* USG_COMPAT */ |
| 104 | |
| 105 | static long |
| 106 | detzcode(codep) |
| 107 | char * codep; |
| 108 | { |
| 109 | register long result; |
| 110 | register int i; |
| 111 | |
| 112 | result = 0; |
| 113 | for (i = 0; i < 4; ++i) |
| 114 | result = (result << 8) | (codep[i] & 0xff); |
| 115 | return result; |
| 116 | } |
| 117 | |
| 118 | static |
| 119 | tzload(name) |
| 120 | register char * name; |
| 121 | { |
| 122 | register int i; |
| 123 | register int fid; |
| 124 | |
| 125 | if (name == 0 && (name = TZDEFAULT) == 0) |
| 126 | return -1; |
| 127 | { |
| 128 | register char * p; |
| 129 | register int doaccess; |
| 130 | char fullname[MAXPATHLEN]; |
| 131 | |
| 132 | doaccess = name[0] == '/'; |
| 133 | if (!doaccess) { |
| 134 | if ((p = TZDIR) == 0) |
| 135 | return -1; |
| 136 | if ((strlen(p) + strlen(name) + 1) >= sizeof fullname) |
| 137 | return -1; |
| 138 | (void) strcpy(fullname, p); |
| 139 | (void) strcat(fullname, "/"); |
| 140 | (void) strcat(fullname, name); |
| 141 | /* |
| 142 | ** Set doaccess if '.' (as in "../") shows up in name. |
| 143 | */ |
| 144 | while (*name != '\0') |
| 145 | if (*name++ == '.') |
| 146 | doaccess = TRUE; |
| 147 | name = fullname; |
| 148 | } |
| 149 | if (doaccess && access(name, 4) != 0) |
| 150 | return -1; |
| 151 | if ((fid = open(name, 0)) == -1) |
| 152 | return -1; |
| 153 | } |
| 154 | { |
| 155 | register char * p; |
| 156 | register struct tzhead * tzhp; |
| 157 | char buf[sizeof s]; |
| 158 | |
| 159 | i = read(fid, buf, sizeof buf); |
| 160 | if (close(fid) != 0 || i < sizeof *tzhp) |
| 161 | return -1; |
| 162 | tzhp = (struct tzhead *) buf; |
| 163 | s.timecnt = (int) detzcode(tzhp->tzh_timecnt); |
| 164 | s.typecnt = (int) detzcode(tzhp->tzh_typecnt); |
| 165 | s.charcnt = (int) detzcode(tzhp->tzh_charcnt); |
| 166 | if (s.timecnt > TZ_MAX_TIMES || |
| 167 | s.typecnt == 0 || |
| 168 | s.typecnt > TZ_MAX_TYPES || |
| 169 | s.charcnt > TZ_MAX_CHARS) |
| 170 | return -1; |
| 171 | if (i < sizeof *tzhp + |
| 172 | s.timecnt * (4 + sizeof (char)) + |
| 173 | s.typecnt * (4 + 2 * sizeof (char)) + |
| 174 | s.charcnt * sizeof (char)) |
| 175 | return -1; |
| 176 | p = buf + sizeof *tzhp; |
| 177 | for (i = 0; i < s.timecnt; ++i) { |
| 178 | s.ats[i] = detzcode(p); |
| 179 | p += 4; |
| 180 | } |
| 181 | for (i = 0; i < s.timecnt; ++i) |
| 182 | s.types[i] = (unsigned char) *p++; |
| 183 | for (i = 0; i < s.typecnt; ++i) { |
| 184 | register struct ttinfo * ttisp; |
| 185 | |
| 186 | ttisp = &s.ttis[i]; |
| 187 | ttisp->tt_gmtoff = detzcode(p); |
| 188 | p += 4; |
| 189 | ttisp->tt_isdst = (unsigned char) *p++; |
| 190 | ttisp->tt_abbrind = (unsigned char) *p++; |
| 191 | } |
| 192 | for (i = 0; i < s.charcnt; ++i) |
| 193 | s.chars[i] = *p++; |
| 194 | s.chars[i] = '\0'; /* ensure '\0' at end */ |
| 195 | } |
| 196 | /* |
| 197 | ** Check that all the local time type indices are valid. |
| 198 | */ |
| 199 | for (i = 0; i < s.timecnt; ++i) |
| 200 | if (s.types[i] >= s.typecnt) |
| 201 | return -1; |
| 202 | /* |
| 203 | ** Check that all abbreviation indices are valid. |
| 204 | */ |
| 205 | for (i = 0; i < s.typecnt; ++i) |
| 206 | if (s.ttis[i].tt_abbrind >= s.charcnt) |
| 207 | return -1; |
| 208 | /* |
| 209 | ** Set tzname elements to initial values. |
| 210 | */ |
| 211 | tzname[0] = tzname[1] = &s.chars[0]; |
| 212 | #ifdef USG_COMPAT |
| 213 | timezone = -s.ttis[0].tt_gmtoff; |
| 214 | daylight = 0; |
| 215 | #endif /* USG_COMPAT */ |
| 216 | for (i = 1; i < s.typecnt; ++i) { |
| 217 | register struct ttinfo * ttisp; |
| 218 | |
| 219 | ttisp = &s.ttis[i]; |
| 220 | if (ttisp->tt_isdst) { |
| 221 | tzname[1] = &s.chars[ttisp->tt_abbrind]; |
| 222 | #ifdef USG_COMPAT |
| 223 | daylight = 1; |
| 224 | #endif /* USG_COMPAT */ |
| 225 | } else { |
| 226 | tzname[0] = &s.chars[ttisp->tt_abbrind]; |
| 227 | #ifdef USG_COMPAT |
| 228 | timezone = -ttisp->tt_gmtoff; |
| 229 | #endif /* USG_COMPAT */ |
| 230 | } |
| 231 | } |
| 232 | return 0; |
| 233 | } |
| 234 | |
| 235 | static |
| 236 | tzsetkernel() |
| 237 | { |
| 238 | struct timeval tv; |
| 239 | struct timezone tz; |
| 240 | char *_tztab(); |
| 241 | |
| 242 | if (gettimeofday(&tv, &tz)) |
| 243 | return -1; |
| 244 | s.timecnt = 0; /* UNIX counts *west* of Greenwich */ |
| 245 | s.ttis[0].tt_gmtoff = tz.tz_minuteswest * -SECS_PER_MIN; |
| 246 | s.ttis[0].tt_abbrind = 0; |
| 247 | (void)strcpy(s.chars, _tztab(tz.tz_minuteswest, 0)); |
| 248 | tzname[0] = tzname[1] = s.chars; |
| 249 | #ifdef USG_COMPAT |
| 250 | timezone = tz.tz_minuteswest * 60; |
| 251 | daylight = tz.tz_dsttime; |
| 252 | #endif /* USG_COMPAT */ |
| 253 | return 0; |
| 254 | } |
| 255 | |
| 256 | static |
| 257 | tzsetgmt() |
| 258 | { |
| 259 | s.timecnt = 0; |
| 260 | s.ttis[0].tt_gmtoff = 0; |
| 261 | s.ttis[0].tt_abbrind = 0; |
| 262 | (void) strcpy(s.chars, "GMT"); |
| 263 | tzname[0] = tzname[1] = s.chars; |
| 264 | #ifdef USG_COMPAT |
| 265 | timezone = 0; |
| 266 | daylight = 0; |
| 267 | #endif /* USG_COMPAT */ |
| 268 | } |
| 269 | |
| 270 | void |
| 271 | tzset() |
| 272 | { |
| 273 | register char * name; |
| 274 | |
| 275 | tz_is_set = TRUE; |
| 276 | name = getenv("TZ"); |
| 277 | if (!name || *name) { /* did not request GMT */ |
| 278 | if (name && !tzload(name)) /* requested name worked */ |
| 279 | return; |
| 280 | if (!tzload((char *)0)) /* default name worked */ |
| 281 | return; |
| 282 | if (!tzsetkernel()) /* kernel guess worked */ |
| 283 | return; |
| 284 | } |
| 285 | tzsetgmt(); /* GMT is default */ |
| 286 | } |
| 287 | |
| 288 | struct tm * |
| 289 | localtime(timep) |
| 290 | time_t * timep; |
| 291 | { |
| 292 | register struct ttinfo * ttisp; |
| 293 | register struct tm * tmp; |
| 294 | register int i; |
| 295 | time_t t; |
| 296 | |
| 297 | if (!tz_is_set) |
| 298 | (void) tzset(); |
| 299 | t = *timep; |
| 300 | if (s.timecnt == 0 || t < s.ats[0]) { |
| 301 | i = 0; |
| 302 | while (s.ttis[i].tt_isdst) |
| 303 | if (++i >= s.timecnt) { |
| 304 | i = 0; |
| 305 | break; |
| 306 | } |
| 307 | } else { |
| 308 | for (i = 1; i < s.timecnt; ++i) |
| 309 | if (t < s.ats[i]) |
| 310 | break; |
| 311 | i = s.types[i - 1]; |
| 312 | } |
| 313 | ttisp = &s.ttis[i]; |
| 314 | /* |
| 315 | ** To get (wrong) behavior that's compatible with System V Release 2.0 |
| 316 | ** you'd replace the statement below with |
| 317 | ** tmp = offtime((time_t) (t + ttisp->tt_gmtoff), 0L); |
| 318 | */ |
| 319 | tmp = offtime(&t, ttisp->tt_gmtoff); |
| 320 | tmp->tm_isdst = ttisp->tt_isdst; |
| 321 | tzname[tmp->tm_isdst] = &s.chars[ttisp->tt_abbrind]; |
| 322 | tmp->tm_zone = &s.chars[ttisp->tt_abbrind]; |
| 323 | return tmp; |
| 324 | } |
| 325 | |
| 326 | struct tm * |
| 327 | gmtime(clock) |
| 328 | time_t * clock; |
| 329 | { |
| 330 | register struct tm * tmp; |
| 331 | |
| 332 | tmp = offtime(clock, 0L); |
| 333 | tzname[0] = "GMT"; |
| 334 | tmp->tm_zone = "GMT"; /* UCT ? */ |
| 335 | return tmp; |
| 336 | } |
| 337 | |
| 338 | static int mon_lengths[2][MONS_PER_YEAR] = { |
| 339 | 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31, |
| 340 | 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 |
| 341 | }; |
| 342 | |
| 343 | static int year_lengths[2] = { |
| 344 | DAYS_PER_NYEAR, DAYS_PER_LYEAR |
| 345 | }; |
| 346 | |
| 347 | struct tm * |
| 348 | offtime(clock, offset) |
| 349 | time_t * clock; |
| 350 | long offset; |
| 351 | { |
| 352 | register struct tm * tmp; |
| 353 | register long days; |
| 354 | register long rem; |
| 355 | register int y; |
| 356 | register int yleap; |
| 357 | register int * ip; |
| 358 | static struct tm tm; |
| 359 | |
| 360 | tmp = &tm; |
| 361 | days = *clock / SECS_PER_DAY; |
| 362 | rem = *clock % SECS_PER_DAY; |
| 363 | rem += offset; |
| 364 | while (rem < 0) { |
| 365 | rem += SECS_PER_DAY; |
| 366 | --days; |
| 367 | } |
| 368 | while (rem >= SECS_PER_DAY) { |
| 369 | rem -= SECS_PER_DAY; |
| 370 | ++days; |
| 371 | } |
| 372 | tmp->tm_hour = (int) (rem / SECS_PER_HOUR); |
| 373 | rem = rem % SECS_PER_HOUR; |
| 374 | tmp->tm_min = (int) (rem / SECS_PER_MIN); |
| 375 | tmp->tm_sec = (int) (rem % SECS_PER_MIN); |
| 376 | tmp->tm_wday = (int) ((EPOCH_WDAY + days) % DAYS_PER_WEEK); |
| 377 | if (tmp->tm_wday < 0) |
| 378 | tmp->tm_wday += DAYS_PER_WEEK; |
| 379 | y = EPOCH_YEAR; |
| 380 | if (days >= 0) |
| 381 | for ( ; ; ) { |
| 382 | yleap = isleap(y); |
| 383 | if (days < (long) year_lengths[yleap]) |
| 384 | break; |
| 385 | ++y; |
| 386 | days = days - (long) year_lengths[yleap]; |
| 387 | } |
| 388 | else do { |
| 389 | --y; |
| 390 | yleap = isleap(y); |
| 391 | days = days + (long) year_lengths[yleap]; |
| 392 | } while (days < 0); |
| 393 | tmp->tm_year = y - TM_YEAR_BASE; |
| 394 | tmp->tm_yday = (int) days; |
| 395 | ip = mon_lengths[yleap]; |
| 396 | for (tmp->tm_mon = 0; days >= (long) ip[tmp->tm_mon]; ++(tmp->tm_mon)) |
| 397 | days = days - (long) ip[tmp->tm_mon]; |
| 398 | tmp->tm_mday = (int) (days + 1); |
| 399 | tmp->tm_isdst = 0; |
| 400 | tmp->tm_zone = ""; |
| 401 | tmp->tm_gmtoff = offset; |
| 402 | return tmp; |
| 403 | } |