1 /* 2 * Copyright (c) 1989 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Berkeley. The name of the 11 * University may not be used to endorse or promote products derived 12 * from this software without specific prior written permission. 13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 16 */ 17 18 #ifdef LIBC_RCS 19 static const char rcsid[] = 20 "$FreeBSD$"; 21 #endif 22 23 #ifndef lint 24 #ifndef NOID 25 static const char elsieid[] = "@(#)strftime.c 7.38"; 26 /* 27 ** Based on the UCB version with the ID appearing below. 28 ** This is ANSIish only when "multibyte character == plain character". 29 */ 30 #endif /* !defined NOID */ 31 #endif /* !defined lint */ 32 33 #include "private.h" 34 35 #ifndef LIBC_SCCS 36 #ifndef lint 37 static const char sccsid[] = "@(#)strftime.c 5.4 (Berkeley) 3/14/89"; 38 #endif /* !defined lint */ 39 #endif /* !defined LIBC_SCCS */ 40 41 #include "tzfile.h" 42 #include <fcntl.h> 43 #include <sys/stat.h> 44 #include "timelocal.h" 45 46 static char * _add P((const char *, char *, const char *)); 47 static char * _conv P((int, const char *, char *, const char *)); 48 static char * _fmt P((const char *, const struct tm *, char *, const char *)); 49 50 size_t strftime P((char *, size_t, const char *, const struct tm *)); 51 52 extern char * tzname[]; 53 54 size_t 55 strftime(s, maxsize, format, t) 56 char *const s; 57 const size_t maxsize; 58 const char *const format; 59 const struct tm *const t; 60 { 61 char *p; 62 63 tzset(); 64 p = _fmt(((format == NULL) ? "%c" : format), t, s, s + maxsize); 65 if (p == s + maxsize) 66 return 0; 67 *p = '\0'; 68 return p - s; 69 } 70 71 static char * 72 _fmt(format, t, pt, ptlim) 73 const char *format; 74 const struct tm *const t; 75 char *pt; 76 const char *const ptlim; 77 { 78 int Ealternative, Oalternative; 79 80 for ( ; *format; ++format) { 81 if (*format == '%') { 82 Ealternative = 0; 83 Oalternative = 0; 84 label: 85 switch (*++format) { 86 case '\0': 87 --format; 88 break; 89 case 'A': 90 pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ? 91 "?" : Locale->weekday[t->tm_wday], 92 pt, ptlim); 93 continue; 94 case 'a': 95 pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ? 96 "?" : Locale->wday[t->tm_wday], 97 pt, ptlim); 98 continue; 99 case 'B': 100 pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ? 101 "?" : (Oalternative ? Locale->alt_month : 102 Locale->month)[t->tm_mon], 103 pt, ptlim); 104 continue; 105 case 'b': 106 case 'h': 107 pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ? 108 "?" : Locale->mon[t->tm_mon], 109 pt, ptlim); 110 continue; 111 case 'C': 112 /* 113 ** %C used to do a... 114 ** _fmt("%a %b %e %X %Y", t); 115 ** ...whereas now POSIX 1003.2 calls for 116 ** something completely different. 117 ** (ado, 5/24/93) 118 */ 119 pt = _conv((t->tm_year + TM_YEAR_BASE) / 100, 120 "%02d", pt, ptlim); 121 continue; 122 case 'c': 123 /* NOTE: c_fmt is intentionally ignored */ 124 pt = _fmt("%a %Ef %T %Y", t, pt, ptlim); 125 continue; 126 case 'D': 127 pt = _fmt("%m/%d/%y", t, pt, ptlim); 128 continue; 129 case 'd': 130 pt = _conv(t->tm_mday, "%02d", pt, ptlim); 131 continue; 132 case 'E': 133 if (Ealternative || Oalternative) 134 break; 135 Ealternative++; 136 goto label; 137 case 'O': 138 /* 139 ** POSIX locale extensions, a la 140 ** Arnold Robbins' strftime version 3.0. 141 ** The sequences 142 ** %Ec %EC %Ex %EX %Ey %EY 143 ** %Od %oe %OH %OI %Om %OM 144 ** %OS %Ou %OU %OV %Ow %OW %Oy 145 ** are supposed to provide alternate 146 ** representations. 147 ** (ado, 5/24/93) 148 ** 149 ** FreeBSD extensions 150 ** %OB %Ef %EF 151 */ 152 if (Ealternative || Oalternative) 153 break; 154 Oalternative++; 155 goto label; 156 case 'e': 157 pt = _conv(t->tm_mday, "%2d", pt, ptlim); 158 continue; 159 case 'f': 160 if (!Ealternative) 161 break; 162 pt = _fmt(Locale->Ef_fmt, t, pt, ptlim); 163 continue; 164 case 'F': 165 if (!Ealternative) 166 break; 167 pt = _fmt(Locale->EF_fmt, t, pt, ptlim); 168 continue; 169 case 'H': 170 pt = _conv(t->tm_hour, "%02d", pt, ptlim); 171 continue; 172 case 'I': 173 pt = _conv((t->tm_hour % 12) ? 174 (t->tm_hour % 12) : 12, 175 "%02d", pt, ptlim); 176 continue; 177 case 'j': 178 pt = _conv(t->tm_yday + 1, "%03d", pt, ptlim); 179 continue; 180 case 'k': 181 /* 182 ** This used to be... 183 ** _conv(t->tm_hour % 12 ? 184 ** t->tm_hour % 12 : 12, 2, ' '); 185 ** ...and has been changed to the below to 186 ** match SunOS 4.1.1 and Arnold Robbins' 187 ** strftime version 3.0. That is, "%k" and 188 ** "%l" have been swapped. 189 ** (ado, 5/24/93) 190 */ 191 pt = _conv(t->tm_hour, "%2d", pt, ptlim); 192 continue; 193 #ifdef KITCHEN_SINK 194 case 'K': 195 /* 196 ** After all this time, still unclaimed! 197 */ 198 pt = _add("kitchen sink", pt, ptlim); 199 continue; 200 #endif /* defined KITCHEN_SINK */ 201 case 'l': 202 /* 203 ** This used to be... 204 ** _conv(t->tm_hour, 2, ' '); 205 ** ...and has been changed to the below to 206 ** match SunOS 4.1.1 and Arnold Robbin's 207 ** strftime version 3.0. That is, "%k" and 208 ** "%l" have been swapped. 209 ** (ado, 5/24/93) 210 */ 211 pt = _conv((t->tm_hour % 12) ? 212 (t->tm_hour % 12) : 12, 213 "%2d", pt, ptlim); 214 continue; 215 case 'M': 216 pt = _conv(t->tm_min, "%02d", pt, ptlim); 217 continue; 218 case 'm': 219 pt = _conv(t->tm_mon + 1, "%02d", pt, ptlim); 220 continue; 221 case 'n': 222 pt = _add("\n", pt, ptlim); 223 continue; 224 case 'p': 225 pt = _add((t->tm_hour >= 12) ? 226 Locale->pm : 227 Locale->am, 228 pt, ptlim); 229 continue; 230 case 'R': 231 pt = _fmt("%H:%M", t, pt, ptlim); 232 continue; 233 case 'r': 234 pt = _fmt("%I:%M:%S %p", t, pt, ptlim); 235 continue; 236 case 'S': 237 pt = _conv(t->tm_sec, "%02d", pt, ptlim); 238 continue; 239 case 's': 240 { 241 struct tm tm; 242 char buf[INT_STRLEN_MAXIMUM( 243 time_t) + 1]; 244 time_t mkt; 245 246 tm = *t; 247 mkt = mktime(&tm); 248 if (TYPE_SIGNED(time_t)) 249 (void) sprintf(buf, "%ld", 250 (long) mkt); 251 else (void) sprintf(buf, "%lu", 252 (unsigned long) mkt); 253 pt = _add(buf, pt, ptlim); 254 } 255 continue; 256 case 'T': 257 pt = _fmt("%H:%M:%S", t, pt, ptlim); 258 continue; 259 case 't': 260 pt = _add("\t", pt, ptlim); 261 continue; 262 case 'U': 263 pt = _conv((t->tm_yday + 7 - t->tm_wday) / 7, 264 "%02d", pt, ptlim); 265 continue; 266 case 'u': 267 /* 268 ** From Arnold Robbins' strftime version 3.0: 269 ** "ISO 8601: Weekday as a decimal number 270 ** [1 (Monday) - 7]" 271 ** (ado, 5/24/93) 272 */ 273 pt = _conv((t->tm_wday == 0) ? 7 : t->tm_wday, 274 "%d", pt, ptlim); 275 continue; 276 case 'V': /* ISO 8601 week number */ 277 case 'G': /* ISO 8601 year (four digits) */ 278 case 'g': /* ISO 8601 year (two digits) */ 279 /* 280 ** From Arnold Robbins' strftime version 3.0: "the week number of the 281 ** year (the first Monday as the first day of week 1) as a decimal number 282 ** (01-53)." 283 ** (ado, 1993-05-24) 284 ** 285 ** From "http://www.ft.uni-erlangen.de/~mskuhn/iso-time.html" by Markus Kuhn: 286 ** "Week 01 of a year is per definition the first week which has the 287 ** Thursday in this year, which is equivalent to the week which contains 288 ** the fourth day of January. In other words, the first week of a new year 289 ** is the week which has the majority of its days in the new year. Week 01 290 ** might also contain days from the previous year and the week before week 291 ** 01 of a year is the last week (52 or 53) of the previous year even if 292 ** it contains days from the new year. A week starts with Monday (day 1) 293 ** and ends with Sunday (day 7). For example, the first week of the year 294 ** 1997 lasts from 1996-12-30 to 1997-01-05..." 295 ** (ado, 1996-01-02) 296 */ 297 { 298 int year; 299 int yday; 300 int wday; 301 int w; 302 303 year = t->tm_year + TM_YEAR_BASE; 304 yday = t->tm_yday; 305 wday = t->tm_wday; 306 for ( ; ; ) { 307 int len; 308 int bot; 309 int top; 310 311 len = isleap(year) ? 312 DAYSPERLYEAR : 313 DAYSPERNYEAR; 314 /* 315 ** What yday (-3 ... 3) does 316 ** the ISO year begin on? 317 */ 318 bot = ((yday + 11 - wday) % 319 DAYSPERWEEK) - 3; 320 /* 321 ** What yday does the NEXT 322 ** ISO year begin on? 323 */ 324 top = bot - 325 (len % DAYSPERWEEK); 326 if (top < -3) 327 top += DAYSPERWEEK; 328 top += len; 329 if (yday >= top) { 330 ++year; 331 w = 1; 332 break; 333 } 334 if (yday >= bot) { 335 w = 1 + ((yday - bot) / 336 DAYSPERWEEK); 337 break; 338 } 339 --year; 340 yday += isleap(year) ? 341 DAYSPERLYEAR : 342 DAYSPERNYEAR; 343 } 344 #ifdef XPG4_1994_04_09 345 if ((w == 52 346 && t->tm_mon == TM_JANUARY) 347 || (w == 1 348 && t->tm_mon == TM_DECEMBER)) 349 w = 53; 350 #endif /* defined XPG4_1994_04_09 */ 351 if (*format == 'V') 352 pt = _conv(w, "%02d", 353 pt, ptlim); 354 else if (*format == 'g') { 355 pt = _conv(year % 100, "%02d", 356 pt, ptlim); 357 } else pt = _conv(year, "%04d", 358 pt, ptlim); 359 } 360 continue; 361 case 'v': 362 /* 363 ** From Arnold Robbins' strftime version 3.0: 364 ** "date as dd-bbb-YYYY" 365 ** (ado, 5/24/93) 366 */ 367 pt = _fmt("%e-%b-%Y", t, pt, ptlim); 368 continue; 369 case 'W': 370 pt = _conv((t->tm_yday + 7 - 371 (t->tm_wday ? 372 (t->tm_wday - 1) : 6)) / 7, 373 "%02d", pt, ptlim); 374 continue; 375 case 'w': 376 pt = _conv(t->tm_wday, "%d", pt, ptlim); 377 continue; 378 case 'X': 379 pt = _fmt(Locale->X_fmt, t, pt, ptlim); 380 continue; 381 case 'x': 382 pt = _fmt(Locale->x_fmt, t, pt, ptlim); 383 continue; 384 case 'y': 385 pt = _conv((t->tm_year + TM_YEAR_BASE) % 100, 386 "%02d", pt, ptlim); 387 continue; 388 case 'Y': 389 pt = _conv(t->tm_year + TM_YEAR_BASE, "%04d", 390 pt, ptlim); 391 continue; 392 case 'Z': 393 if (t->tm_zone != NULL) 394 pt = _add(t->tm_zone, pt, ptlim); 395 else 396 if (t->tm_isdst == 0 || t->tm_isdst == 1) { 397 pt = _add(tzname[t->tm_isdst], 398 pt, ptlim); 399 } else pt = _add("?", pt, ptlim); 400 continue; 401 case 'z': 402 { 403 long absoff; 404 if (t->tm_gmtoff >= 0) { 405 absoff = t->tm_gmtoff; 406 pt = _add("+", pt, ptlim); 407 } else { 408 absoff = -t->tm_gmtoff; 409 pt = _add("-", pt, ptlim); 410 } 411 pt = _conv(absoff / 3600, "%02d", 412 pt, ptlim); 413 pt = _conv((absoff % 3600) / 60, "%02d", 414 pt, ptlim); 415 }; 416 continue; 417 case '+': 418 pt = _fmt(Locale->date_fmt, t, pt, ptlim); 419 continue; 420 case '%': 421 /* 422 * X311J/88-090 (4.12.3.5): if conversion char is 423 * undefined, behavior is undefined. Print out the 424 * character itself as printf(3) also does. 425 */ 426 default: 427 break; 428 } 429 } 430 if (pt == ptlim) 431 break; 432 *pt++ = *format; 433 } 434 return pt; 435 } 436 437 static char * 438 _conv(n, format, pt, ptlim) 439 const int n; 440 const char *const format; 441 char *const pt; 442 const char *const ptlim; 443 { 444 char buf[INT_STRLEN_MAXIMUM(int) + 1]; 445 446 (void) snprintf(buf, sizeof(buf), format, n); 447 return _add(buf, pt, ptlim); 448 } 449 450 static char * 451 _add(str, pt, ptlim) 452 const char *str; 453 char *pt; 454 const char *const ptlim; 455 { 456 while (pt < ptlim && (*pt = *str++) != '\0') 457 ++pt; 458 return pt; 459 } 460