strftime.c revision 22305
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 19static const char rcsid[] = 20 "$FreeBSD: head/lib/libc/stdtime/strftime.c 22305 1997-02-05 19:22:04Z ache $"; 21#endif 22 23#ifndef lint 24#ifndef NOID 25static 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 37static 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 <locale.h> 44#include <sys/stat.h> 45 46struct lc_time_T { 47 const char * mon[12]; 48 const char * month[12]; 49 const char * wday[7]; 50 const char * weekday[7]; 51 const char * X_fmt; 52 const char * x_fmt; 53 const char * c_fmt; 54 const char * am; 55 const char * pm; 56 const char * date_fmt; 57}; 58 59static struct lc_time_T localebuf; 60static int using_locale; 61 62#define Locale (using_locale ? &localebuf : &C_time_locale) 63 64static const struct lc_time_T C_time_locale = { 65 { 66 "Jan", "Feb", "Mar", "Apr", "May", "Jun", 67 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" 68 }, { 69 "January", "February", "March", "April", "May", "June", 70 "July", "August", "September", "October", "November", "December" 71 }, { 72 "Sun", "Mon", "Tue", "Wed", 73 "Thu", "Fri", "Sat" 74 }, { 75 "Sunday", "Monday", "Tuesday", "Wednesday", 76 "Thursday", "Friday", "Saturday" 77 }, 78 79 /* X_fmt */ 80 "%H:%M:%S", 81 82 /* 83 ** x_fmt 84 ** Since the C language standard calls for 85 ** "date, using locale's date format," anything goes. 86 ** Using just numbers (as here) makes Quakers happier; 87 ** it's also compatible with SVR4. 88 */ 89 "%m/%d/%y", 90 91 /* 92 ** c_fmt (ctime-compatible) 93 ** Note that 94 ** "%a %b %d %H:%M:%S %Y" 95 ** is used by Solaris 2.3. 96 */ 97 "%a %b %e %X %Y", 98 99 /* am */ 100 "AM", 101 102 /* pm */ 103 "PM", 104 105 /* date_fmt */ 106 "%a %b %e %X %Z %Y" 107}; 108 109static char * _add P((const char *, char *, const char *)); 110static char * _conv P((int, const char *, char *, const char *)); 111static char * _fmt P((const char *, const struct tm *, char *, const char *)); 112static char * _secs P((const struct tm *, char *, const char *)); 113 114size_t strftime P((char *, size_t, const char *, const struct tm *)); 115 116extern char * tzname[]; 117 118size_t 119strftime(s, maxsize, format, t) 120 char *const s; 121 const size_t maxsize; 122 const char *const format; 123 const struct tm *const t; 124{ 125 char *p; 126 127 tzset(); 128 p = _fmt(((format == NULL) ? "%c" : format), t, s, s + maxsize); 129 if (p == s + maxsize) 130 return 0; 131 *p = '\0'; 132 return p - s; 133} 134 135static char * 136_fmt(format, t, pt, ptlim) 137 const char *format; 138 const struct tm *const t; 139 char *pt; 140 const char *const ptlim; 141{ 142 for ( ; *format; ++format) { 143 if (*format == '%') { 144label: 145 switch (*++format) { 146 case '\0': 147 --format; 148 break; 149 case 'A': 150 pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ? 151 "?" : Locale->weekday[t->tm_wday], 152 pt, ptlim); 153 continue; 154 case 'a': 155 pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ? 156 "?" : Locale->wday[t->tm_wday], 157 pt, ptlim); 158 continue; 159 case 'B': 160 pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ? 161 "?" : Locale->month[t->tm_mon], 162 pt, ptlim); 163 continue; 164 case 'b': 165 case 'h': 166 pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ? 167 "?" : Locale->mon[t->tm_mon], 168 pt, ptlim); 169 continue; 170 case 'C': 171 /* 172 ** %C used to do a... 173 ** _fmt("%a %b %e %X %Y", t); 174 ** ...whereas now POSIX 1003.2 calls for 175 ** something completely different. 176 ** (ado, 5/24/93) 177 */ 178 pt = _conv((t->tm_year + TM_YEAR_BASE) / 100, 179 "%02d", pt, ptlim); 180 continue; 181 case 'c': 182 pt = _fmt(Locale->c_fmt, t, pt, ptlim); 183 continue; 184 case 'D': 185 pt = _fmt("%m/%d/%y", t, pt, ptlim); 186 continue; 187 case 'd': 188 pt = _conv(t->tm_mday, "%02d", pt, ptlim); 189 continue; 190 case 'E': 191 case 'O': 192 /* 193 ** POSIX locale extensions, a la 194 ** Arnold Robbins' strftime version 3.0. 195 ** The sequences 196 ** %Ec %EC %Ex %Ey %EY 197 ** %Od %oe %OH %OI %Om %OM 198 ** %OS %Ou %OU %OV %Ow %OW %Oy 199 ** are supposed to provide alternate 200 ** representations. 201 ** (ado, 5/24/93) 202 */ 203 goto label; 204 case 'e': 205 pt = _conv(t->tm_mday, "%2d", pt, ptlim); 206 continue; 207 case 'H': 208 pt = _conv(t->tm_hour, "%02d", pt, ptlim); 209 continue; 210 case 'I': 211 pt = _conv((t->tm_hour % 12) ? 212 (t->tm_hour % 12) : 12, 213 "%02d", pt, ptlim); 214 continue; 215 case 'j': 216 pt = _conv(t->tm_yday + 1, "%03d", pt, ptlim); 217 continue; 218 case 'k': 219 /* 220 ** This used to be... 221 ** _conv(t->tm_hour % 12 ? 222 ** t->tm_hour % 12 : 12, 2, ' '); 223 ** ...and has been changed to the below to 224 ** match SunOS 4.1.1 and Arnold Robbins' 225 ** strftime version 3.0. That is, "%k" and 226 ** "%l" have been swapped. 227 ** (ado, 5/24/93) 228 */ 229 pt = _conv(t->tm_hour, "%2d", pt, ptlim); 230 continue; 231#ifdef KITCHEN_SINK 232 case 'K': 233 /* 234 ** After all this time, still unclaimed! 235 */ 236 pt = _add("kitchen sink", pt, ptlim); 237 continue; 238#endif /* defined KITCHEN_SINK */ 239 case 'l': 240 /* 241 ** This used to be... 242 ** _conv(t->tm_hour, 2, ' '); 243 ** ...and has been changed to the below to 244 ** match SunOS 4.1.1 and Arnold Robbin's 245 ** strftime version 3.0. That is, "%k" and 246 ** "%l" have been swapped. 247 ** (ado, 5/24/93) 248 */ 249 pt = _conv((t->tm_hour % 12) ? 250 (t->tm_hour % 12) : 12, 251 "%2d", pt, ptlim); 252 continue; 253 case 'M': 254 pt = _conv(t->tm_min, "%02d", pt, ptlim); 255 continue; 256 case 'm': 257 pt = _conv(t->tm_mon + 1, "%02d", pt, ptlim); 258 continue; 259 case 'n': 260 pt = _add("\n", pt, ptlim); 261 continue; 262 case 'p': 263 pt = _add((t->tm_hour >= 12) ? 264 Locale->pm : 265 Locale->am, 266 pt, ptlim); 267 continue; 268 case 'R': 269 pt = _fmt("%H:%M", t, pt, ptlim); 270 continue; 271 case 'r': 272 pt = _fmt("%I:%M:%S %p", t, pt, ptlim); 273 continue; 274 case 'S': 275 pt = _conv(t->tm_sec, "%02d", pt, ptlim); 276 continue; 277 case 's': 278 pt = _secs(t, pt, ptlim); 279 continue; 280 case 'T': 281 pt = _fmt("%H:%M:%S", t, pt, ptlim); 282 continue; 283 case 't': 284 pt = _add("\t", pt, ptlim); 285 continue; 286 case 'U': 287 pt = _conv((t->tm_yday + 7 - t->tm_wday) / 7, 288 "%02d", pt, ptlim); 289 continue; 290 case 'u': 291 /* 292 ** From Arnold Robbins' strftime version 3.0: 293 ** "ISO 8601: Weekday as a decimal number 294 ** [1 (Monday) - 7]" 295 ** (ado, 5/24/93) 296 */ 297 pt = _conv((t->tm_wday == 0) ? 7 : t->tm_wday, 298 "%d", pt, ptlim); 299 continue; 300 case 'V': 301 /* 302 ** From Arnold Robbins' strftime version 3.0: 303 ** "the week number of the year (the first 304 ** Monday as the first day of week 1) as a 305 ** decimal number (01-53). The method for 306 ** determining the week number is as specified 307 ** by ISO 8601 (to wit: if the week containing 308 ** January 1 has four or more days in the new 309 ** year, then it is week 1, otherwise it is 310 ** week 53 of the previous year and the next 311 ** week is week 1)." 312 ** (ado, 5/24/93) 313 */ 314 /* 315 ** XXX--If January 1 falls on a Friday, 316 ** January 1-3 are part of week 53 of the 317 ** previous year. By analogy, if January 318 ** 1 falls on a Thursday, are December 29-31 319 ** of the PREVIOUS year part of week 1??? 320 ** (ado 5/24/93) 321 */ 322 /* 323 ** You are understood not to expect this. 324 */ 325 { 326 int i; 327 328 i = (t->tm_yday + 10 - (t->tm_wday ? 329 (t->tm_wday - 1) : 6)) / 7; 330 if (i == 0) { 331 /* 332 ** What day of the week does 333 ** January 1 fall on? 334 */ 335 i = t->tm_wday - 336 (t->tm_yday - 1); 337 /* 338 ** Fri Jan 1: 53 339 ** Sun Jan 1: 52 340 ** Sat Jan 1: 53 if previous 341 ** year a leap 342 ** year, else 52 343 */ 344 if (i == TM_FRIDAY) 345 i = 53; 346 else if (i == TM_SUNDAY) 347 i = 52; 348 else i = isleap(t->tm_year + 349 TM_YEAR_BASE) ? 350 53 : 52; 351#ifdef XPG4_1994_04_09 352 /* 353 ** As of 4/9/94, though, 354 ** XPG4 calls for 53 355 ** unconditionally. 356 */ 357 i = 53; 358#endif /* defined XPG4_1994_04_09 */ 359 } 360 pt = _conv(i, "%02d", pt, ptlim); 361 } 362 continue; 363 case 'v': 364 /* 365 ** From Arnold Robbins' strftime version 3.0: 366 ** "date as dd-bbb-YYYY" 367 ** (ado, 5/24/93) 368 */ 369 pt = _fmt("%e-%b-%Y", t, pt, ptlim); 370 continue; 371 case 'W': 372 pt = _conv((t->tm_yday + 7 - 373 (t->tm_wday ? 374 (t->tm_wday - 1) : 6)) / 7, 375 "%02d", pt, ptlim); 376 continue; 377 case 'w': 378 pt = _conv(t->tm_wday, "%d", pt, ptlim); 379 continue; 380 case 'X': 381 pt = _fmt(Locale->X_fmt, t, pt, ptlim); 382 continue; 383 case 'x': 384 pt = _fmt(Locale->x_fmt, t, pt, ptlim); 385 continue; 386 case 'y': 387 pt = _conv((t->tm_year + TM_YEAR_BASE) % 100, 388 "%02d", pt, ptlim); 389 continue; 390 case 'Y': 391 pt = _conv(t->tm_year + TM_YEAR_BASE, "%04d", 392 pt, ptlim); 393 continue; 394 case 'Z': 395 if (t->tm_zone != NULL) 396 pt = _add(t->tm_zone, pt, ptlim); 397 else 398 if (t->tm_isdst == 0 || t->tm_isdst == 1) { 399 pt = _add(tzname[t->tm_isdst], 400 pt, ptlim); 401 } else pt = _add("?", pt, ptlim); 402 continue; 403 case '+': 404 pt = _fmt(Locale->date_fmt, t, pt, ptlim); 405 continue; 406 case '%': 407 /* 408 * X311J/88-090 (4.12.3.5): if conversion char is 409 * undefined, behavior is undefined. Print out the 410 * character itself as printf(3) also does. 411 */ 412 default: 413 break; 414 } 415 } 416 if (pt == ptlim) 417 break; 418 *pt++ = *format; 419 } 420 return pt; 421} 422 423static char * 424_conv(n, format, pt, ptlim) 425 const int n; 426 const char *const format; 427 char *const pt; 428 const char *const ptlim; 429{ 430 char buf[INT_STRLEN_MAXIMUM(int) + 1]; 431 432 (void) sprintf(buf, format, n); 433 return _add(buf, pt, ptlim); 434} 435 436static char * 437_secs(t, pt, ptlim) 438 const struct tm *t; 439 char *pt; 440 const char *ptlim; 441{ 442 char buf[INT_STRLEN_MAXIMUM(int) + 1]; 443 register time_t s; 444 struct tm tmp; 445 446 /* Make a copy, mktime(3) modifies the tm struct. */ 447 tmp = *t; 448 s = mktime(&tmp); 449 (void) sprintf(buf, "%ld", s); 450 return _add(buf, pt, ptlim); 451} 452 453static char * 454_add(str, pt, ptlim) 455 const char *str; 456 char *pt; 457 const char *const ptlim; 458{ 459 while (pt < ptlim && (*pt = *str++) != '\0') 460 ++pt; 461 return pt; 462} 463 464extern char *_PathLocale; 465 466int 467__time_load_locale(const char *name) 468{ 469 static char * locale_buf; 470 static char locale_buf_C[] = "C"; 471 472 int fd; 473 char * lbuf; 474 char * p; 475 const char ** ap; 476 const char * plim; 477 char filename[PATH_MAX]; 478 struct stat st; 479 size_t namesize; 480 size_t bufsize; 481 int save_using_locale; 482 483 save_using_locale = using_locale; 484 using_locale = 0; 485 486 if (name == NULL) 487 goto no_locale; 488 489 if (!strcmp(name, "C") || !strcmp(name, "POSIX")) 490 return 0; 491 492 /* 493 ** If the locale name is the same as our cache, use the cache. 494 */ 495 lbuf = locale_buf; 496 if (lbuf != NULL && strcmp(name, lbuf) == 0) { 497 p = lbuf; 498 for (ap = (const char **) &localebuf; 499 ap < (const char **) (&localebuf + 1); 500 ++ap) 501 *ap = p += strlen(p) + 1; 502 using_locale = 1; 503 return 0; 504 } 505 /* 506 ** Slurp the locale file into the cache. 507 */ 508 namesize = strlen(name) + 1; 509 510 if (!_PathLocale) 511 goto no_locale; 512 /* Range checking not needed, name has fixed size */ 513 strcpy(filename, _PathLocale); 514 strcat(filename, "/"); 515 strcat(filename, name); 516 strcat(filename, "/LC_TIME"); 517 fd = open(filename, O_RDONLY); 518 if (fd < 0) 519 goto no_locale; 520 if (fstat(fd, &st) != 0) 521 goto bad_locale; 522 if (st.st_size <= 0) 523 goto bad_locale; 524 bufsize = namesize + st.st_size; 525 locale_buf = NULL; 526 lbuf = (lbuf == NULL || lbuf == locale_buf_C) ? 527 malloc(bufsize) : realloc(lbuf, bufsize); 528 if (lbuf == NULL) 529 goto bad_locale; 530 (void) strcpy(lbuf, name); 531 p = lbuf + namesize; 532 plim = p + st.st_size; 533 if (read(fd, p, (size_t) st.st_size) != st.st_size) 534 goto bad_lbuf; 535 if (close(fd) != 0) 536 goto bad_lbuf; 537 /* 538 ** Parse the locale file into localebuf. 539 */ 540 if (plim[-1] != '\n') 541 goto bad_lbuf; 542 for (ap = (const char **) &localebuf; 543 ap < (const char **) (&localebuf + 1); 544 ++ap) { 545 if (p == plim) 546 goto reset_locale; 547 *ap = p; 548 while (*p != '\n') 549 ++p; 550 *p++ = '\0'; 551 } 552 /* 553 ** Record the successful parse in the cache. 554 */ 555 locale_buf = lbuf; 556 557 using_locale = 1; 558 return 0; 559 560reset_locale: 561 /* 562 * XXX - This may not be the correct thing to do in this case. 563 * setlocale() assumes that we left the old locale alone. 564 */ 565 locale_buf = locale_buf_C; 566 localebuf = C_time_locale; 567 save_using_locale = 0; 568bad_lbuf: 569 free(lbuf); 570bad_locale: 571 (void) close(fd); 572no_locale: 573 using_locale = save_using_locale; 574 return -1; 575} 576