1 /* 2 * Copyright (c) 1989 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * Copyright (c) 2011 The FreeBSD Foundation 6 * 7 * Portions of this software were developed by David Chisnall 8 * under sponsorship from the FreeBSD Foundation. 9 * 10 * Redistribution and use in source and binary forms are permitted 11 * provided that the above copyright notice and this paragraph are 12 * duplicated in all such forms and that any documentation, 13 * advertising materials, and other materials related to such 14 * distribution and use acknowledge that the software was developed 15 * by the University of California, Berkeley. The name of the 16 * University may not be used to endorse or promote products derived 17 * from this software without specific prior written permission. 18 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 21 */ 22 23 #include "namespace.h" 24 #include "private.h" 25 26 #include "tzfile.h" 27 #include <fcntl.h> 28 #include <sys/stat.h> 29 #include <stdio.h> 30 #include "un-namespace.h" 31 #include "timelocal.h" 32 33 static char * _add(const char *, char *, const char *); 34 static char * _conv(int, const char *, char *, const char *, locale_t); 35 static char * _fmt(const char *, const struct tm *, char *, const char *, 36 int *, locale_t); 37 static char * _yconv(int, int, int, int, char *, const char *, locale_t); 38 39 extern char * tzname[]; 40 41 #ifndef YEAR_2000_NAME 42 #define YEAR_2000_NAME "CHECK_STRFTIME_FORMATS_FOR_TWO_DIGIT_YEARS" 43 #endif /* !defined YEAR_2000_NAME */ 44 45 #define IN_NONE 0 46 #define IN_SOME 1 47 #define IN_THIS 2 48 #define IN_ALL 3 49 50 #define PAD_DEFAULT 0 51 #define PAD_LESS 1 52 #define PAD_SPACE 2 53 #define PAD_ZERO 3 54 55 static const char fmt_padding[][4][5] = { 56 /* DEFAULT, LESS, SPACE, ZERO */ 57 #define PAD_FMT_MONTHDAY 0 58 #define PAD_FMT_HMS 0 59 #define PAD_FMT_CENTURY 0 60 #define PAD_FMT_SHORTYEAR 0 61 #define PAD_FMT_MONTH 0 62 #define PAD_FMT_WEEKOFYEAR 0 63 #define PAD_FMT_DAYOFMONTH 0 64 { "%02d", "%d", "%2d", "%02d" }, 65 #define PAD_FMT_SDAYOFMONTH 1 66 #define PAD_FMT_SHMS 1 67 { "%2d", "%d", "%2d", "%02d" }, 68 #define PAD_FMT_DAYOFYEAR 2 69 { "%03d", "%d", "%3d", "%03d" }, 70 #define PAD_FMT_YEAR 3 71 { "%04d", "%d", "%4d", "%04d" } 72 }; 73 74 size_t 75 strftime_l(char * __restrict s, size_t maxsize, const char * __restrict format, 76 const struct tm * __restrict t, locale_t loc) 77 { 78 char * p; 79 int warn; 80 FIX_LOCALE(loc); 81 82 tzset(); 83 warn = IN_NONE; 84 p = _fmt(((format == NULL) ? "%c" : format), t, s, s + maxsize, &warn, loc); 85 #ifndef NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU 86 if (warn != IN_NONE && getenv(YEAR_2000_NAME) != NULL) { 87 (void) fprintf_l(stderr, loc, "\n"); 88 if (format == NULL) 89 (void) fputs("NULL strftime format ", stderr); 90 else (void) fprintf_l(stderr, loc, "strftime format \"%s\" ", 91 format); 92 (void) fputs("yields only two digits of years in ", stderr); 93 if (warn == IN_SOME) 94 (void) fputs("some locales", stderr); 95 else if (warn == IN_THIS) 96 (void) fputs("the current locale", stderr); 97 else (void) fputs("all locales", stderr); 98 (void) fputs("\n", stderr); 99 } 100 #endif /* !defined NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU */ 101 if (p == s + maxsize) 102 return (0); 103 *p = '\0'; 104 return p - s; 105 } 106 107 size_t 108 strftime(char * __restrict s, size_t maxsize, const char * __restrict format, 109 const struct tm * __restrict t) 110 { 111 return strftime_l(s, maxsize, format, t, __get_locale()); 112 } 113 114 static char * 115 _fmt(const char *format, const struct tm * const t, char *pt, 116 const char * const ptlim, int *warnp, locale_t loc) 117 { 118 int Ealternative, Oalternative, PadIndex; 119 struct lc_time_T *tptr = __get_current_time_locale(loc); 120 121 for ( ; *format; ++format) { 122 if (*format == '%') { 123 Ealternative = 0; 124 Oalternative = 0; 125 PadIndex = PAD_DEFAULT; 126 label: 127 switch (*++format) { 128 case '\0': 129 --format; 130 break; 131 case 'A': 132 pt = _add((t->tm_wday < 0 || 133 t->tm_wday >= DAYSPERWEEK) ? 134 "?" : tptr->weekday[t->tm_wday], 135 pt, ptlim); 136 continue; 137 case 'a': 138 pt = _add((t->tm_wday < 0 || 139 t->tm_wday >= DAYSPERWEEK) ? 140 "?" : tptr->wday[t->tm_wday], 141 pt, ptlim); 142 continue; 143 case 'B': 144 pt = _add((t->tm_mon < 0 || 145 t->tm_mon >= MONSPERYEAR) ? 146 "?" : (Oalternative ? tptr->alt_month : 147 tptr->month)[t->tm_mon], 148 pt, ptlim); 149 continue; 150 case 'b': 151 case 'h': 152 pt = _add((t->tm_mon < 0 || 153 t->tm_mon >= MONSPERYEAR) ? 154 "?" : tptr->mon[t->tm_mon], 155 pt, ptlim); 156 continue; 157 case 'C': 158 /* 159 * %C used to do a... 160 * _fmt("%a %b %e %X %Y", t); 161 * ...whereas now POSIX 1003.2 calls for 162 * something completely different. 163 * (ado, 1993-05-24) 164 */ 165 pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 0, 166 pt, ptlim, loc); 167 continue; 168 case 'c': 169 { 170 int warn2 = IN_SOME; 171 172 pt = _fmt(tptr->c_fmt, t, pt, ptlim, &warn2, loc); 173 if (warn2 == IN_ALL) 174 warn2 = IN_THIS; 175 if (warn2 > *warnp) 176 *warnp = warn2; 177 } 178 continue; 179 case 'D': 180 pt = _fmt("%m/%d/%y", t, pt, ptlim, warnp, loc); 181 continue; 182 case 'd': 183 pt = _conv(t->tm_mday, 184 fmt_padding[PAD_FMT_DAYOFMONTH][PadIndex], 185 pt, ptlim, loc); 186 continue; 187 case 'E': 188 if (Ealternative || Oalternative) 189 break; 190 Ealternative++; 191 goto label; 192 case 'O': 193 /* 194 * C99 locale modifiers. 195 * The sequences 196 * %Ec %EC %Ex %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 * 202 * FreeBSD extension 203 * %OB 204 */ 205 if (Ealternative || Oalternative) 206 break; 207 Oalternative++; 208 goto label; 209 case 'e': 210 pt = _conv(t->tm_mday, 211 fmt_padding[PAD_FMT_SDAYOFMONTH][PadIndex], 212 pt, ptlim, loc); 213 continue; 214 case 'F': 215 pt = _fmt("%Y-%m-%d", t, pt, ptlim, warnp, loc); 216 continue; 217 case 'H': 218 pt = _conv(t->tm_hour, fmt_padding[PAD_FMT_HMS][PadIndex], 219 pt, ptlim, loc); 220 continue; 221 case 'I': 222 pt = _conv((t->tm_hour % 12) ? 223 (t->tm_hour % 12) : 12, 224 fmt_padding[PAD_FMT_HMS][PadIndex], 225 pt, ptlim, loc); 226 continue; 227 case 'j': 228 pt = _conv(t->tm_yday + 1, 229 fmt_padding[PAD_FMT_DAYOFYEAR][PadIndex], 230 pt, ptlim, loc); 231 continue; 232 case 'k': 233 /* 234 * This used to be... 235 * _conv(t->tm_hour % 12 ? 236 * t->tm_hour % 12 : 12, 2, ' '); 237 * ...and has been changed to the below to 238 * match SunOS 4.1.1 and Arnold Robbins' 239 * strftime version 3.0. That is, "%k" and 240 * "%l" have been swapped. 241 * (ado, 1993-05-24) 242 */ 243 pt = _conv(t->tm_hour, fmt_padding[PAD_FMT_SHMS][PadIndex], 244 pt, ptlim, loc); 245 continue; 246 #ifdef KITCHEN_SINK 247 case 'K': 248 /* 249 ** After all this time, still unclaimed! 250 */ 251 pt = _add("kitchen sink", pt, ptlim); 252 continue; 253 #endif /* defined KITCHEN_SINK */ 254 case 'l': 255 /* 256 * This used to be... 257 * _conv(t->tm_hour, 2, ' '); 258 * ...and has been changed to the below to 259 * match SunOS 4.1.1 and Arnold Robbin's 260 * strftime version 3.0. That is, "%k" and 261 * "%l" have been swapped. 262 * (ado, 1993-05-24) 263 */ 264 pt = _conv((t->tm_hour % 12) ? 265 (t->tm_hour % 12) : 12, 266 fmt_padding[PAD_FMT_SHMS][PadIndex], 267 pt, ptlim, loc); 268 continue; 269 case 'M': 270 pt = _conv(t->tm_min, fmt_padding[PAD_FMT_HMS][PadIndex], 271 pt, ptlim, loc); 272 continue; 273 case 'm': 274 pt = _conv(t->tm_mon + 1, 275 fmt_padding[PAD_FMT_MONTH][PadIndex], 276 pt, ptlim, loc); 277 continue; 278 case 'n': 279 pt = _add("\n", pt, ptlim); 280 continue; 281 case 'p': 282 pt = _add((t->tm_hour >= (HOURSPERDAY / 2)) ? 283 tptr->pm : tptr->am, 284 pt, ptlim); 285 continue; 286 case 'R': 287 pt = _fmt("%H:%M", t, pt, ptlim, warnp, loc); 288 continue; 289 case 'r': 290 pt = _fmt(tptr->ampm_fmt, t, pt, ptlim, 291 warnp, loc); 292 continue; 293 case 'S': 294 pt = _conv(t->tm_sec, fmt_padding[PAD_FMT_HMS][PadIndex], 295 pt, ptlim, loc); 296 continue; 297 case 's': 298 { 299 struct tm tm; 300 char buf[INT_STRLEN_MAXIMUM( 301 time_t) + 1]; 302 time_t mkt; 303 304 tm = *t; 305 mkt = timeoff(&tm, t->tm_gmtoff); 306 if (TYPE_SIGNED(time_t)) 307 (void) sprintf_l(buf, loc, "%ld", 308 (long) mkt); 309 else (void) sprintf_l(buf, loc, "%lu", 310 (unsigned long) mkt); 311 pt = _add(buf, pt, ptlim); 312 } 313 continue; 314 case 'T': 315 pt = _fmt("%H:%M:%S", t, pt, ptlim, warnp, loc); 316 continue; 317 case 't': 318 pt = _add("\t", pt, ptlim); 319 continue; 320 case 'U': 321 pt = _conv((t->tm_yday + DAYSPERWEEK - 322 t->tm_wday) / DAYSPERWEEK, 323 fmt_padding[PAD_FMT_WEEKOFYEAR][PadIndex], 324 pt, ptlim, loc); 325 continue; 326 case 'u': 327 /* 328 * From Arnold Robbins' strftime version 3.0: 329 * "ISO 8601: Weekday as a decimal number 330 * [1 (Monday) - 7]" 331 * (ado, 1993-05-24) 332 */ 333 pt = _conv((t->tm_wday == 0) ? 334 DAYSPERWEEK : t->tm_wday, 335 "%d", pt, ptlim, loc); 336 continue; 337 case 'V': /* ISO 8601 week number */ 338 case 'G': /* ISO 8601 year (four digits) */ 339 case 'g': /* ISO 8601 year (two digits) */ 340 /* 341 * From Arnold Robbins' strftime version 3.0: "the week number of the 342 * year (the first Monday as the first day of week 1) as a decimal number 343 * (01-53)." 344 * (ado, 1993-05-24) 345 * 346 * From "http://www.ft.uni-erlangen.de/~mskuhn/iso-time.html" by Markus Kuhn: 347 * "Week 01 of a year is per definition the first week which has the 348 * Thursday in this year, which is equivalent to the week which contains 349 * the fourth day of January. In other words, the first week of a new year 350 * is the week which has the majority of its days in the new year. Week 01 351 * might also contain days from the previous year and the week before week 352 * 01 of a year is the last week (52 or 53) of the previous year even if 353 * it contains days from the new year. A week starts with Monday (day 1) 354 * and ends with Sunday (day 7). For example, the first week of the year 355 * 1997 lasts from 1996-12-30 to 1997-01-05..." 356 * (ado, 1996-01-02) 357 */ 358 { 359 int year; 360 int base; 361 int yday; 362 int wday; 363 int w; 364 365 year = t->tm_year; 366 base = TM_YEAR_BASE; 367 yday = t->tm_yday; 368 wday = t->tm_wday; 369 for ( ; ; ) { 370 int len; 371 int bot; 372 int top; 373 374 len = isleap_sum(year, base) ? 375 DAYSPERLYEAR : 376 DAYSPERNYEAR; 377 /* 378 * What yday (-3 ... 3) does 379 * the ISO year begin on? 380 */ 381 bot = ((yday + 11 - wday) % 382 DAYSPERWEEK) - 3; 383 /* 384 * What yday does the NEXT 385 * ISO year begin on? 386 */ 387 top = bot - 388 (len % DAYSPERWEEK); 389 if (top < -3) 390 top += DAYSPERWEEK; 391 top += len; 392 if (yday >= top) { 393 ++base; 394 w = 1; 395 break; 396 } 397 if (yday >= bot) { 398 w = 1 + ((yday - bot) / 399 DAYSPERWEEK); 400 break; 401 } 402 --base; 403 yday += isleap_sum(year, base) ? 404 DAYSPERLYEAR : 405 DAYSPERNYEAR; 406 } 407 #ifdef XPG4_1994_04_09 408 if ((w == 52 && 409 t->tm_mon == TM_JANUARY) || 410 (w == 1 && 411 t->tm_mon == TM_DECEMBER)) 412 w = 53; 413 #endif /* defined XPG4_1994_04_09 */ 414 if (*format == 'V') 415 pt = _conv(w, fmt_padding[PAD_FMT_WEEKOFYEAR][PadIndex], 416 pt, ptlim, loc); 417 else if (*format == 'g') { 418 *warnp = IN_ALL; 419 pt = _yconv(year, base, 0, 1, 420 pt, ptlim, loc); 421 } else pt = _yconv(year, base, 1, 1, 422 pt, ptlim, loc); 423 } 424 continue; 425 case 'v': 426 /* 427 * From Arnold Robbins' strftime version 3.0: 428 * "date as dd-bbb-YYYY" 429 * (ado, 1993-05-24) 430 */ 431 pt = _fmt("%e-%b-%Y", t, pt, ptlim, warnp, loc); 432 continue; 433 case 'W': 434 pt = _conv((t->tm_yday + DAYSPERWEEK - 435 (t->tm_wday ? 436 (t->tm_wday - 1) : 437 (DAYSPERWEEK - 1))) / DAYSPERWEEK, 438 fmt_padding[PAD_FMT_WEEKOFYEAR][PadIndex], 439 pt, ptlim, loc); 440 continue; 441 case 'w': 442 pt = _conv(t->tm_wday, "%d", pt, ptlim, loc); 443 continue; 444 case 'X': 445 pt = _fmt(tptr->X_fmt, t, pt, ptlim, warnp, loc); 446 continue; 447 case 'x': 448 { 449 int warn2 = IN_SOME; 450 451 pt = _fmt(tptr->x_fmt, t, pt, ptlim, &warn2, loc); 452 if (warn2 == IN_ALL) 453 warn2 = IN_THIS; 454 if (warn2 > *warnp) 455 *warnp = warn2; 456 } 457 continue; 458 case 'y': 459 *warnp = IN_ALL; 460 pt = _yconv(t->tm_year, TM_YEAR_BASE, 0, 1, 461 pt, ptlim, loc); 462 continue; 463 case 'Y': 464 pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 1, 465 pt, ptlim, loc); 466 continue; 467 case 'Z': 468 #ifdef TM_ZONE 469 if (t->TM_ZONE != NULL) 470 pt = _add(t->TM_ZONE, pt, ptlim); 471 else 472 #endif /* defined TM_ZONE */ 473 if (t->tm_isdst >= 0) 474 pt = _add(tzname[t->tm_isdst != 0], 475 pt, ptlim); 476 /* 477 * C99 says that %Z must be replaced by the 478 * empty string if the time zone is not 479 * determinable. 480 */ 481 continue; 482 case 'z': 483 { 484 int diff; 485 char const * sign; 486 487 if (t->tm_isdst < 0) 488 continue; 489 #ifdef TM_GMTOFF 490 diff = t->TM_GMTOFF; 491 #else /* !defined TM_GMTOFF */ 492 /* 493 * C99 says that the UTC offset must 494 * be computed by looking only at 495 * tm_isdst. This requirement is 496 * incorrect, since it means the code 497 * must rely on magic (in this case 498 * altzone and timezone), and the 499 * magic might not have the correct 500 * offset. Doing things correctly is 501 * tricky and requires disobeying C99; 502 * see GNU C strftime for details. 503 * For now, punt and conform to the 504 * standard, even though it's incorrect. 505 * 506 * C99 says that %z must be replaced by the 507 * empty string if the time zone is not 508 * determinable, so output nothing if the 509 * appropriate variables are not available. 510 */ 511 if (t->tm_isdst == 0) 512 #ifdef USG_COMPAT 513 diff = -timezone; 514 #else /* !defined USG_COMPAT */ 515 continue; 516 #endif /* !defined USG_COMPAT */ 517 else 518 #ifdef ALTZONE 519 diff = -altzone; 520 #else /* !defined ALTZONE */ 521 continue; 522 #endif /* !defined ALTZONE */ 523 #endif /* !defined TM_GMTOFF */ 524 if (diff < 0) { 525 sign = "-"; 526 diff = -diff; 527 } else 528 sign = "+"; 529 pt = _add(sign, pt, ptlim); 530 diff /= SECSPERMIN; 531 diff = (diff / MINSPERHOUR) * 100 + 532 (diff % MINSPERHOUR); 533 pt = _conv(diff, 534 fmt_padding[PAD_FMT_YEAR][PadIndex], 535 pt, ptlim, loc); 536 } 537 continue; 538 case '+': 539 pt = _fmt(tptr->date_fmt, t, pt, ptlim, 540 warnp, loc); 541 continue; 542 case '-': 543 if (PadIndex != PAD_DEFAULT) 544 break; 545 PadIndex = PAD_LESS; 546 goto label; 547 case '_': 548 if (PadIndex != PAD_DEFAULT) 549 break; 550 PadIndex = PAD_SPACE; 551 goto label; 552 case '0': 553 if (PadIndex != PAD_DEFAULT) 554 break; 555 PadIndex = PAD_ZERO; 556 goto label; 557 case '%': 558 /* 559 * X311J/88-090 (4.12.3.5): if conversion char is 560 * undefined, behavior is undefined. Print out the 561 * character itself as printf(3) also does. 562 */ 563 default: 564 break; 565 } 566 } 567 if (pt == ptlim) 568 break; 569 *pt++ = *format; 570 } 571 return (pt); 572 } 573 574 static char * 575 _conv(const int n, const char * const format, char * const pt, 576 const char * const ptlim, locale_t loc) 577 { 578 char buf[INT_STRLEN_MAXIMUM(int) + 1]; 579 580 (void) sprintf_l(buf, loc, format, n); 581 return _add(buf, pt, ptlim); 582 } 583 584 static char * 585 _add(const char *str, char *pt, const char * const ptlim) 586 { 587 while (pt < ptlim && (*pt = *str++) != '\0') 588 ++pt; 589 return (pt); 590 } 591 592 /* 593 * POSIX and the C Standard are unclear or inconsistent about 594 * what %C and %y do if the year is negative or exceeds 9999. 595 * Use the convention that %C concatenated with %y yields the 596 * same output as %Y, and that %Y contains at least 4 bytes, 597 * with more only if necessary. 598 */ 599 600 static char * 601 _yconv(const int a, const int b, const int convert_top, const int convert_yy, 602 char *pt, const char * const ptlim, locale_t loc) 603 { 604 register int lead; 605 register int trail; 606 607 #define DIVISOR 100 608 trail = a % DIVISOR + b % DIVISOR; 609 lead = a / DIVISOR + b / DIVISOR + trail / DIVISOR; 610 trail %= DIVISOR; 611 if (trail < 0 && lead > 0) { 612 trail += DIVISOR; 613 --lead; 614 } else if (lead < 0 && trail > 0) { 615 trail -= DIVISOR; 616 ++lead; 617 } 618 if (convert_top) { 619 if (lead == 0 && trail < 0) 620 pt = _add("-0", pt, ptlim); 621 else pt = _conv(lead, "%02d", pt, ptlim, loc); 622 } 623 if (convert_yy) 624 pt = _conv(((trail < 0) ? -trail : trail), "%02d", pt, 625 ptlim, loc); 626 return (pt); 627 } 628