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 * @(#)strftime.c 7.38 18 * $FreeBSD: src/lib/libc/stdtime/strftime.c,v 1.25.2.4 2002/03/12 17:24:54 phantom Exp $ 19 * $DragonFly: src/lib/libc/stdtime/strftime.c,v 1.2 2003/06/17 04:26:46 dillon Exp $ 20 */ 21 22 #include "private.h" 23 24 #ifndef LIBC_SCCS 25 #ifndef lint 26 static const char sccsid[] = "@(#)strftime.c 5.4 (Berkeley) 3/14/89"; 27 #endif /* !defined lint */ 28 #endif /* !defined LIBC_SCCS */ 29 30 #include "tzfile.h" 31 #include <fcntl.h> 32 #include <sys/stat.h> 33 #include "timelocal.h" 34 35 static char * _add P((const char *, char *, const char *)); 36 static char * _conv P((int, const char *, char *, const char *)); 37 static char * _fmt P((const char *, const struct tm *, char *, const char *)); 38 39 size_t strftime P((char *, size_t, const char *, const struct tm *)); 40 41 extern char * tzname[]; 42 43 size_t 44 strftime(s, maxsize, format, t) 45 char *const s; 46 const size_t maxsize; 47 const char *const format; 48 const struct tm *const t; 49 { 50 char *p; 51 52 tzset(); 53 p = _fmt(((format == NULL) ? "%c" : format), t, s, s + maxsize); 54 if (p == s + maxsize) 55 return 0; 56 *p = '\0'; 57 return p - s; 58 } 59 60 static char * 61 _fmt(format, t, pt, ptlim) 62 const char *format; 63 const struct tm *const t; 64 char *pt; 65 const char *const ptlim; 66 { 67 int Ealternative, Oalternative; 68 struct lc_time_T *tptr = __get_current_time_locale(); 69 70 for ( ; *format; ++format) { 71 if (*format == '%') { 72 Ealternative = 0; 73 Oalternative = 0; 74 label: 75 switch (*++format) { 76 case '\0': 77 --format; 78 break; 79 case 'A': 80 pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ? 81 "?" : tptr->weekday[t->tm_wday], 82 pt, ptlim); 83 continue; 84 case 'a': 85 pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ? 86 "?" : tptr->wday[t->tm_wday], 87 pt, ptlim); 88 continue; 89 case 'B': 90 pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ? 91 "?" : (Oalternative ? tptr->alt_month : 92 tptr->month)[t->tm_mon], 93 pt, ptlim); 94 continue; 95 case 'b': 96 case 'h': 97 pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ? 98 "?" : tptr->mon[t->tm_mon], 99 pt, ptlim); 100 continue; 101 case 'C': 102 /* 103 ** %C used to do a... 104 ** _fmt("%a %b %e %X %Y", t); 105 ** ...whereas now POSIX 1003.2 calls for 106 ** something completely different. 107 ** (ado, 5/24/93) 108 */ 109 pt = _conv((t->tm_year + TM_YEAR_BASE) / 100, 110 "%02d", pt, ptlim); 111 continue; 112 case 'c': 113 pt = _fmt(tptr->c_fmt, t, pt, ptlim); 114 continue; 115 case 'D': 116 pt = _fmt("%m/%d/%y", t, pt, ptlim); 117 continue; 118 case 'd': 119 pt = _conv(t->tm_mday, "%02d", pt, ptlim); 120 continue; 121 case 'E': 122 if (Ealternative || Oalternative) 123 break; 124 Ealternative++; 125 goto label; 126 case 'O': 127 /* 128 ** POSIX locale extensions, a la 129 ** Arnold Robbins' strftime version 3.0. 130 ** The sequences 131 ** %Ec %EC %Ex %EX %Ey %EY 132 ** %Od %oe %OH %OI %Om %OM 133 ** %OS %Ou %OU %OV %Ow %OW %Oy 134 ** are supposed to provide alternate 135 ** representations. 136 ** (ado, 5/24/93) 137 ** 138 ** FreeBSD extensions 139 ** %OB %Ef %EF 140 */ 141 if (Ealternative || Oalternative) 142 break; 143 Oalternative++; 144 goto label; 145 case 'e': 146 pt = _conv(t->tm_mday, "%2d", pt, ptlim); 147 continue; 148 case 'F': 149 pt = _fmt("%Y-%m-%d", t, pt, ptlim); 150 continue; 151 case 'H': 152 pt = _conv(t->tm_hour, "%02d", pt, ptlim); 153 continue; 154 case 'I': 155 pt = _conv((t->tm_hour % 12) ? 156 (t->tm_hour % 12) : 12, 157 "%02d", pt, ptlim); 158 continue; 159 case 'j': 160 pt = _conv(t->tm_yday + 1, "%03d", pt, ptlim); 161 continue; 162 case 'k': 163 /* 164 ** This used to be... 165 ** _conv(t->tm_hour % 12 ? 166 ** t->tm_hour % 12 : 12, 2, ' '); 167 ** ...and has been changed to the below to 168 ** match SunOS 4.1.1 and Arnold Robbins' 169 ** strftime version 3.0. That is, "%k" and 170 ** "%l" have been swapped. 171 ** (ado, 5/24/93) 172 */ 173 pt = _conv(t->tm_hour, "%2d", pt, ptlim); 174 continue; 175 #ifdef KITCHEN_SINK 176 case 'K': 177 /* 178 ** After all this time, still unclaimed! 179 */ 180 pt = _add("kitchen sink", pt, ptlim); 181 continue; 182 #endif /* defined KITCHEN_SINK */ 183 case 'l': 184 /* 185 ** This used to be... 186 ** _conv(t->tm_hour, 2, ' '); 187 ** ...and has been changed to the below to 188 ** match SunOS 4.1.1 and Arnold Robbin's 189 ** strftime version 3.0. That is, "%k" and 190 ** "%l" have been swapped. 191 ** (ado, 5/24/93) 192 */ 193 pt = _conv((t->tm_hour % 12) ? 194 (t->tm_hour % 12) : 12, 195 "%2d", pt, ptlim); 196 continue; 197 case 'M': 198 pt = _conv(t->tm_min, "%02d", pt, ptlim); 199 continue; 200 case 'm': 201 pt = _conv(t->tm_mon + 1, "%02d", pt, ptlim); 202 continue; 203 case 'n': 204 pt = _add("\n", pt, ptlim); 205 continue; 206 case 'p': 207 pt = _add((t->tm_hour >= 12) ? 208 tptr->pm : 209 tptr->am, 210 pt, ptlim); 211 continue; 212 case 'R': 213 pt = _fmt("%H:%M", t, pt, ptlim); 214 continue; 215 case 'r': 216 pt = _fmt(tptr->ampm_fmt, t, pt, ptlim); 217 continue; 218 case 'S': 219 pt = _conv(t->tm_sec, "%02d", pt, ptlim); 220 continue; 221 case 's': 222 { 223 struct tm tm; 224 char buf[INT_STRLEN_MAXIMUM( 225 time_t) + 1]; 226 time_t mkt; 227 228 tm = *t; 229 mkt = mktime(&tm); 230 if (TYPE_SIGNED(time_t)) 231 (void) sprintf(buf, "%ld", 232 (long) mkt); 233 else (void) sprintf(buf, "%lu", 234 (unsigned long) mkt); 235 pt = _add(buf, pt, ptlim); 236 } 237 continue; 238 case 'T': 239 pt = _fmt("%H:%M:%S", t, pt, ptlim); 240 continue; 241 case 't': 242 pt = _add("\t", pt, ptlim); 243 continue; 244 case 'U': 245 pt = _conv((t->tm_yday + 7 - t->tm_wday) / 7, 246 "%02d", pt, ptlim); 247 continue; 248 case 'u': 249 /* 250 ** From Arnold Robbins' strftime version 3.0: 251 ** "ISO 8601: Weekday as a decimal number 252 ** [1 (Monday) - 7]" 253 ** (ado, 5/24/93) 254 */ 255 pt = _conv((t->tm_wday == 0) ? 7 : t->tm_wday, 256 "%d", pt, ptlim); 257 continue; 258 case 'V': /* ISO 8601 week number */ 259 case 'G': /* ISO 8601 year (four digits) */ 260 case 'g': /* ISO 8601 year (two digits) */ 261 /* 262 ** From Arnold Robbins' strftime version 3.0: "the week number of the 263 ** year (the first Monday as the first day of week 1) as a decimal number 264 ** (01-53)." 265 ** (ado, 1993-05-24) 266 ** 267 ** From "http://www.ft.uni-erlangen.de/~mskuhn/iso-time.html" by Markus Kuhn: 268 ** "Week 01 of a year is per definition the first week which has the 269 ** Thursday in this year, which is equivalent to the week which contains 270 ** the fourth day of January. In other words, the first week of a new year 271 ** is the week which has the majority of its days in the new year. Week 01 272 ** might also contain days from the previous year and the week before week 273 ** 01 of a year is the last week (52 or 53) of the previous year even if 274 ** it contains days from the new year. A week starts with Monday (day 1) 275 ** and ends with Sunday (day 7). For example, the first week of the year 276 ** 1997 lasts from 1996-12-30 to 1997-01-05..." 277 ** (ado, 1996-01-02) 278 */ 279 { 280 int year; 281 int yday; 282 int wday; 283 int w; 284 285 year = t->tm_year + TM_YEAR_BASE; 286 yday = t->tm_yday; 287 wday = t->tm_wday; 288 for ( ; ; ) { 289 int len; 290 int bot; 291 int top; 292 293 len = isleap(year) ? 294 DAYSPERLYEAR : 295 DAYSPERNYEAR; 296 /* 297 ** What yday (-3 ... 3) does 298 ** the ISO year begin on? 299 */ 300 bot = ((yday + 11 - wday) % 301 DAYSPERWEEK) - 3; 302 /* 303 ** What yday does the NEXT 304 ** ISO year begin on? 305 */ 306 top = bot - 307 (len % DAYSPERWEEK); 308 if (top < -3) 309 top += DAYSPERWEEK; 310 top += len; 311 if (yday >= top) { 312 ++year; 313 w = 1; 314 break; 315 } 316 if (yday >= bot) { 317 w = 1 + ((yday - bot) / 318 DAYSPERWEEK); 319 break; 320 } 321 --year; 322 yday += isleap(year) ? 323 DAYSPERLYEAR : 324 DAYSPERNYEAR; 325 } 326 #ifdef XPG4_1994_04_09 327 if ((w == 52 328 && t->tm_mon == TM_JANUARY) 329 || (w == 1 330 && t->tm_mon == TM_DECEMBER)) 331 w = 53; 332 #endif /* defined XPG4_1994_04_09 */ 333 if (*format == 'V') 334 pt = _conv(w, "%02d", 335 pt, ptlim); 336 else if (*format == 'g') { 337 pt = _conv(year % 100, "%02d", 338 pt, ptlim); 339 } else pt = _conv(year, "%04d", 340 pt, ptlim); 341 } 342 continue; 343 case 'v': 344 /* 345 ** From Arnold Robbins' strftime version 3.0: 346 ** "date as dd-bbb-YYYY" 347 ** (ado, 5/24/93) 348 */ 349 pt = _fmt("%e-%b-%Y", t, pt, ptlim); 350 continue; 351 case 'W': 352 pt = _conv((t->tm_yday + 7 - 353 (t->tm_wday ? 354 (t->tm_wday - 1) : 6)) / 7, 355 "%02d", pt, ptlim); 356 continue; 357 case 'w': 358 pt = _conv(t->tm_wday, "%d", pt, ptlim); 359 continue; 360 case 'X': 361 pt = _fmt(tptr->X_fmt, t, pt, ptlim); 362 continue; 363 case 'x': 364 pt = _fmt(tptr->x_fmt, t, pt, ptlim); 365 continue; 366 case 'y': 367 pt = _conv((t->tm_year + TM_YEAR_BASE) % 100, 368 "%02d", pt, ptlim); 369 continue; 370 case 'Y': 371 pt = _conv(t->tm_year + TM_YEAR_BASE, "%04d", 372 pt, ptlim); 373 continue; 374 case 'Z': 375 if (t->tm_zone != NULL) 376 pt = _add(t->tm_zone, pt, ptlim); 377 else 378 if (t->tm_isdst == 0 || t->tm_isdst == 1) { 379 pt = _add(tzname[t->tm_isdst], 380 pt, ptlim); 381 } else pt = _add("?", pt, ptlim); 382 continue; 383 case 'z': 384 { 385 long absoff; 386 if (t->tm_gmtoff >= 0) { 387 absoff = t->tm_gmtoff; 388 pt = _add("+", pt, ptlim); 389 } else { 390 absoff = -t->tm_gmtoff; 391 pt = _add("-", pt, ptlim); 392 } 393 pt = _conv(absoff / 3600, "%02d", 394 pt, ptlim); 395 pt = _conv((absoff % 3600) / 60, "%02d", 396 pt, ptlim); 397 }; 398 continue; 399 case '+': 400 pt = _fmt(tptr->date_fmt, t, pt, ptlim); 401 continue; 402 case '%': 403 /* 404 * X311J/88-090 (4.12.3.5): if conversion char is 405 * undefined, behavior is undefined. Print out the 406 * character itself as printf(3) also does. 407 */ 408 default: 409 break; 410 } 411 } 412 if (pt == ptlim) 413 break; 414 *pt++ = *format; 415 } 416 return pt; 417 } 418 419 static char * 420 _conv(n, format, pt, ptlim) 421 const int n; 422 const char *const format; 423 char *const pt; 424 const char *const ptlim; 425 { 426 char buf[INT_STRLEN_MAXIMUM(int) + 1]; 427 428 (void) sprintf(buf, format, n); 429 return _add(buf, pt, ptlim); 430 } 431 432 static char * 433 _add(str, pt, ptlim) 434 const char *str; 435 char *pt; 436 const char *const ptlim; 437 { 438 while (pt < ptlim && (*pt = *str++) != '\0') 439 ++pt; 440 return pt; 441 } 442