strftime.c revision 1.45
1 /* $NetBSD: strftime.c,v 1.45 2019/04/07 14:51:14 christos Exp $ */ 2 3 /* Convert a broken-down timestamp to a string. */ 4 5 /* Copyright 1989 The Regents of the University of California. 6 All rights reserved. 7 8 Redistribution and use in source and binary forms, with or without 9 modification, are permitted provided that the following conditions 10 are met: 11 1. Redistributions of source code must retain the above copyright 12 notice, this list of conditions and the following disclaimer. 13 2. Redistributions in binary form must reproduce the above copyright 14 notice, this list of conditions and the following disclaimer in the 15 documentation and/or other materials provided with the distribution. 16 3. Neither the name of the University nor the names of its contributors 17 may be used to endorse or promote products derived from this software 18 without specific prior written permission. 19 20 THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS" AND 21 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 SUCH DAMAGE. */ 31 32 #include <sys/cdefs.h> 33 #if defined(LIBC_SCCS) && !defined(lint) 34 #if 0 35 static char elsieid[] = "@(#)strftime.c 7.64"; 36 static char elsieid[] = "@(#)strftime.c 8.3"; 37 #else 38 __RCSID("$NetBSD: strftime.c,v 1.45 2019/04/07 14:51:14 christos Exp $"); 39 #endif 40 #endif /* LIBC_SCCS and not lint */ 41 42 #include "namespace.h" 43 44 #include <stddef.h> 45 #include <assert.h> 46 #include <locale.h> 47 #include "setlocale_local.h" 48 49 /* 50 ** Based on the UCB version with the copyright notice appearing above. 51 ** 52 ** This is ANSIish only when "multibyte character == plain character". 53 */ 54 55 #include "private.h" 56 57 /* 58 ** We don't use these extensions in strftime operation even when 59 ** supported by the local tzcode configuration. A strictly 60 ** conforming C application may leave them in undefined state. 61 */ 62 63 #ifdef _LIBC 64 #undef TM_ZONE 65 #undef TM_GMTOFF 66 #endif 67 68 #include <fcntl.h> 69 #include <locale.h> 70 #include <stdio.h> 71 72 #ifndef DEPRECATE_TWO_DIGIT_YEARS 73 # define DEPRECATE_TWO_DIGIT_YEARS false 74 #endif 75 76 #ifdef __weak_alias 77 __weak_alias(strftime_l, _strftime_l) 78 __weak_alias(strftime_lz, _strftime_lz) 79 __weak_alias(strftime_z, _strftime_z) 80 #endif 81 82 #include "sys/localedef.h" 83 #define _TIME_LOCALE(loc) \ 84 ((_TimeLocale *)((loc)->part_impl[(size_t)LC_TIME])) 85 #define c_fmt d_t_fmt 86 87 enum warn { IN_NONE, IN_SOME, IN_THIS, IN_ALL }; 88 89 static char * _add(const char *, char *, const char *); 90 static char * _conv(int, const char *, char *, const char *, locale_t); 91 static char * _fmt(const timezone_t, const char *, const struct tm *, char *, 92 const char *, enum warn *, locale_t); 93 static char * _yconv(int, int, bool, bool, char *, const char *, locale_t); 94 95 #ifndef YEAR_2000_NAME 96 #define YEAR_2000_NAME "CHECK_STRFTIME_FORMATS_FOR_TWO_DIGIT_YEARS" 97 #endif /* !defined YEAR_2000_NAME */ 98 99 #define IN_NONE 0 100 #define IN_SOME 1 101 #define IN_THIS 2 102 #define IN_ALL 3 103 104 #define PAD_DEFAULT 0 105 #define PAD_LESS 1 106 #define PAD_SPACE 2 107 #define PAD_ZERO 3 108 109 static const char fmt_padding[][4][5] = { 110 /* DEFAULT, LESS, SPACE, ZERO */ 111 #define PAD_FMT_MONTHDAY 0 112 #define PAD_FMT_HMS 0 113 #define PAD_FMT_CENTURY 0 114 #define PAD_FMT_SHORTYEAR 0 115 #define PAD_FMT_MONTH 0 116 #define PAD_FMT_WEEKOFYEAR 0 117 #define PAD_FMT_DAYOFMONTH 0 118 { "%02d", "%d", "%2d", "%02d" }, 119 #define PAD_FMT_SDAYOFMONTH 1 120 #define PAD_FMT_SHMS 1 121 { "%2d", "%d", "%2d", "%02d" }, 122 #define PAD_FMT_DAYOFYEAR 2 123 { "%03d", "%d", "%3d", "%03d" }, 124 #define PAD_FMT_YEAR 3 125 { "%04d", "%d", "%4d", "%04d" } 126 }; 127 128 size_t 129 strftime_z(const timezone_t sp, char * __restrict s, size_t maxsize, 130 const char * __restrict format, const struct tm * __restrict t) 131 { 132 return strftime_lz(sp, s, maxsize, format, t, _current_locale()); 133 } 134 135 #if HAVE_STRFTIME_L 136 size_t 137 strftime_l(char *s, size_t maxsize, char const *format, struct tm const *t, 138 locale_t locale) 139 { 140 /* Just call strftime, as only the C locale is supported. */ 141 return strftime(s, maxsize, format, t); 142 } 143 #endif 144 145 size_t 146 strftime_lz(const timezone_t sp, char *const s, const size_t maxsize, 147 const char *const format, const struct tm *const t, locale_t loc) 148 { 149 char * p; 150 enum warn warn = IN_NONE; 151 152 p = _fmt(sp, format, t, s, s + maxsize, &warn, loc); 153 if (/*CONSTCOND*/DEPRECATE_TWO_DIGIT_YEARS 154 && warn != IN_NONE && getenv(YEAR_2000_NAME)) { 155 (void) fprintf(stderr, "\n"); 156 (void) fprintf(stderr, "strftime format \"%s\" ", format); 157 (void) fprintf(stderr, "yields only two digits of years in "); 158 if (warn == IN_SOME) 159 (void) fprintf(stderr, "some locales"); 160 else if (warn == IN_THIS) 161 (void) fprintf(stderr, "the current locale"); 162 else (void) fprintf(stderr, "all locales"); 163 (void) fprintf(stderr, "\n"); 164 } 165 if (p == s + maxsize) 166 return 0; 167 *p = '\0'; 168 return p - s; 169 } 170 171 static char * 172 _fmt(const timezone_t sp, const char *format, const struct tm *t, char *pt, 173 const char *ptlim, enum warn *warnp, locale_t loc) 174 { 175 int Ealternative, Oalternative, PadIndex; 176 _TimeLocale *tptr = _TIME_LOCALE(loc); 177 178 for ( ; *format; ++format) { 179 if (*format == '%') { 180 Ealternative = 0; 181 Oalternative = 0; 182 PadIndex = PAD_DEFAULT; 183 label: 184 switch (*++format) { 185 case '\0': 186 --format; 187 break; 188 case 'A': 189 pt = _add((t->tm_wday < 0 || 190 t->tm_wday >= DAYSPERWEEK) ? 191 "?" : tptr->day[t->tm_wday], 192 pt, ptlim); 193 continue; 194 case 'a': 195 pt = _add((t->tm_wday < 0 || 196 t->tm_wday >= DAYSPERWEEK) ? 197 "?" : tptr->abday[t->tm_wday], 198 pt, ptlim); 199 continue; 200 case 'B': 201 pt = _add((t->tm_mon < 0 || 202 t->tm_mon >= MONSPERYEAR) ? 203 "?" : 204 /* no alt_month in _TimeLocale */ 205 (Oalternative ? tptr->mon/*alt_month*/: 206 tptr->mon)[t->tm_mon], 207 pt, ptlim); 208 continue; 209 case 'b': 210 case 'h': 211 pt = _add((t->tm_mon < 0 || 212 t->tm_mon >= MONSPERYEAR) ? 213 "?" : tptr->abmon[t->tm_mon], 214 pt, ptlim); 215 continue; 216 case 'C': 217 /* 218 ** %C used to do a... 219 ** _fmt("%a %b %e %X %Y", t); 220 ** ...whereas now POSIX 1003.2 calls for 221 ** something completely different. 222 ** (ado, 1993-05-24) 223 */ 224 pt = _yconv(t->tm_year, TM_YEAR_BASE, 225 true, false, pt, ptlim, loc); 226 continue; 227 case 'c': 228 { 229 enum warn warn2 = IN_SOME; 230 231 pt = _fmt(sp, tptr->c_fmt, t, pt, 232 ptlim, &warn2, loc); 233 if (warn2 == IN_ALL) 234 warn2 = IN_THIS; 235 if (warn2 > *warnp) 236 *warnp = warn2; 237 } 238 continue; 239 case 'D': 240 pt = _fmt(sp, "%m/%d/%y", t, pt, ptlim, warnp, 241 loc); 242 continue; 243 case 'd': 244 pt = _conv(t->tm_mday, 245 fmt_padding[PAD_FMT_DAYOFMONTH][PadIndex], 246 pt, ptlim, loc); 247 continue; 248 case 'E': 249 if (Ealternative || Oalternative) 250 break; 251 Ealternative++; 252 goto label; 253 case 'O': 254 /* 255 ** Locale modifiers of C99 and later. 256 ** The sequences 257 ** %Ec %EC %Ex %EX %Ey %EY 258 ** %Od %oe %OH %OI %Om %OM 259 ** %OS %Ou %OU %OV %Ow %OW %Oy 260 ** are supposed to provide alternative 261 ** representations. 262 */ 263 if (Ealternative || Oalternative) 264 break; 265 Oalternative++; 266 goto label; 267 case 'e': 268 pt = _conv(t->tm_mday, 269 fmt_padding[PAD_FMT_SDAYOFMONTH][PadIndex], 270 pt, ptlim, loc); 271 continue; 272 case 'F': 273 pt = _fmt(sp, "%Y-%m-%d", t, pt, ptlim, warnp, 274 loc); 275 continue; 276 case 'H': 277 pt = _conv(t->tm_hour, 278 fmt_padding[PAD_FMT_HMS][PadIndex], 279 pt, ptlim, loc); 280 continue; 281 case 'I': 282 pt = _conv((t->tm_hour % 12) ? 283 (t->tm_hour % 12) : 12, 284 fmt_padding[PAD_FMT_HMS][PadIndex], 285 pt, ptlim, loc); 286 continue; 287 case 'j': 288 pt = _conv(t->tm_yday + 1, 289 fmt_padding[PAD_FMT_DAYOFYEAR][PadIndex], 290 pt, ptlim, loc); 291 continue; 292 case 'k': 293 /* 294 ** This used to be... 295 ** _conv(t->tm_hour % 12 ? 296 ** t->tm_hour % 12 : 12, 2, ' '); 297 ** ...and has been changed to the below to 298 ** match SunOS 4.1.1 and Arnold Robbins' 299 ** strftime version 3.0. That is, "%k" and 300 ** "%l" have been swapped. 301 ** (ado, 1993-05-24) 302 */ 303 pt = _conv(t->tm_hour, 304 fmt_padding[PAD_FMT_SHMS][PadIndex], 305 pt, ptlim, loc); 306 continue; 307 #ifdef KITCHEN_SINK 308 case 'K': 309 /* 310 ** After all this time, still unclaimed! 311 */ 312 pt = _add("kitchen sink", pt, ptlim); 313 continue; 314 #endif /* defined KITCHEN_SINK */ 315 case 'l': 316 /* 317 ** This used to be... 318 ** _conv(t->tm_hour, 2, ' '); 319 ** ...and has been changed to the below to 320 ** match SunOS 4.1.1 and Arnold Robbin's 321 ** strftime version 3.0. That is, "%k" and 322 ** "%l" have been swapped. 323 ** (ado, 1993-05-24) 324 */ 325 pt = _conv((t->tm_hour % 12) ? 326 (t->tm_hour % 12) : 12, 327 fmt_padding[PAD_FMT_SHMS][PadIndex], 328 pt, ptlim, loc); 329 continue; 330 case 'M': 331 pt = _conv(t->tm_min, 332 fmt_padding[PAD_FMT_HMS][PadIndex], 333 pt, ptlim, loc); 334 continue; 335 case 'm': 336 pt = _conv(t->tm_mon + 1, 337 fmt_padding[PAD_FMT_MONTH][PadIndex], 338 pt, ptlim, loc); 339 continue; 340 case 'n': 341 pt = _add("\n", pt, ptlim); 342 continue; 343 case 'p': 344 pt = _add((t->tm_hour >= (HOURSPERDAY / 2)) ? 345 tptr->am_pm[1] : 346 tptr->am_pm[0], 347 pt, ptlim); 348 continue; 349 case 'R': 350 pt = _fmt(sp, "%H:%M", t, pt, ptlim, warnp, 351 loc); 352 continue; 353 case 'r': 354 pt = _fmt(sp, tptr->t_fmt_ampm, t, 355 pt, ptlim, warnp, loc); 356 continue; 357 case 'S': 358 pt = _conv(t->tm_sec, 359 fmt_padding[PAD_FMT_HMS][PadIndex], 360 pt, ptlim, loc); 361 continue; 362 case 's': 363 { 364 struct tm tm; 365 char buf[INT_STRLEN_MAXIMUM( 366 time_t) + 1]; 367 time_t mkt; 368 369 tm = *t; 370 mkt = mktime_z(sp, &tm); 371 /* CONSTCOND */ 372 if (TYPE_SIGNED(time_t)) 373 (void)snprintf(buf, sizeof(buf), 374 "%jd", (intmax_t) mkt); 375 else (void)snprintf(buf, sizeof(buf), 376 "%ju", (uintmax_t) mkt); 377 pt = _add(buf, pt, ptlim); 378 } 379 continue; 380 case 'T': 381 pt = _fmt(sp, "%H:%M:%S", t, pt, ptlim, warnp, 382 loc); 383 continue; 384 case 't': 385 pt = _add("\t", pt, ptlim); 386 continue; 387 case 'U': 388 pt = _conv((t->tm_yday + DAYSPERWEEK - 389 t->tm_wday) / DAYSPERWEEK, 390 fmt_padding[PAD_FMT_WEEKOFYEAR][PadIndex], 391 pt, ptlim, loc); 392 continue; 393 case 'u': 394 /* 395 ** From Arnold Robbins' strftime version 3.0: 396 ** "ISO 8601: Weekday as a decimal number 397 ** [1 (Monday) - 7]" 398 ** (ado, 1993-05-24) 399 */ 400 pt = _conv((t->tm_wday == 0) ? 401 DAYSPERWEEK : t->tm_wday, 402 "%d", pt, ptlim, loc); 403 continue; 404 case 'V': /* ISO 8601 week number */ 405 case 'G': /* ISO 8601 year (four digits) */ 406 case 'g': /* ISO 8601 year (two digits) */ 407 /* 408 ** From Arnold Robbins' strftime version 3.0: "the week number of the 409 ** year (the first Monday as the first day of week 1) as a decimal number 410 ** (01-53)." 411 ** (ado, 1993-05-24) 412 ** 413 ** From <https://www.cl.cam.ac.uk/~mgk25/iso-time.html> by Markus Kuhn: 414 ** "Week 01 of a year is per definition the first week which has the 415 ** Thursday in this year, which is equivalent to the week which contains 416 ** the fourth day of January. In other words, the first week of a new year 417 ** is the week which has the majority of its days in the new year. Week 01 418 ** might also contain days from the previous year and the week before week 419 ** 01 of a year is the last week (52 or 53) of the previous year even if 420 ** it contains days from the new year. A week starts with Monday (day 1) 421 ** and ends with Sunday (day 7). For example, the first week of the year 422 ** 1997 lasts from 1996-12-30 to 1997-01-05..." 423 ** (ado, 1996-01-02) 424 */ 425 { 426 int year; 427 int base; 428 int yday; 429 int wday; 430 int w; 431 432 year = t->tm_year; 433 base = TM_YEAR_BASE; 434 yday = t->tm_yday; 435 wday = t->tm_wday; 436 for ( ; ; ) { 437 int len; 438 int bot; 439 int top; 440 441 len = isleap_sum(year, base) ? 442 DAYSPERLYEAR : 443 DAYSPERNYEAR; 444 /* 445 ** What yday (-3 ... 3) does 446 ** the ISO year begin on? 447 */ 448 bot = ((yday + 11 - wday) % 449 DAYSPERWEEK) - 3; 450 /* 451 ** What yday does the NEXT 452 ** ISO year begin on? 453 */ 454 top = bot - 455 (len % DAYSPERWEEK); 456 if (top < -3) 457 top += DAYSPERWEEK; 458 top += len; 459 if (yday >= top) { 460 ++base; 461 w = 1; 462 break; 463 } 464 if (yday >= bot) { 465 w = 1 + ((yday - bot) / 466 DAYSPERWEEK); 467 break; 468 } 469 --base; 470 yday += isleap_sum(year, base) ? 471 DAYSPERLYEAR : 472 DAYSPERNYEAR; 473 } 474 #ifdef XPG4_1994_04_09 475 if ((w == 52 && 476 t->tm_mon == TM_JANUARY) || 477 (w == 1 && 478 t->tm_mon == TM_DECEMBER)) 479 w = 53; 480 #endif /* defined XPG4_1994_04_09 */ 481 if (*format == 'V') 482 pt = _conv(w, 483 fmt_padding[ 484 PAD_FMT_WEEKOFYEAR][ 485 PadIndex], pt, ptlim, loc); 486 else if (*format == 'g') { 487 *warnp = IN_ALL; 488 pt = _yconv(year, base, 489 false, true, 490 pt, ptlim, loc); 491 } else pt = _yconv(year, base, 492 true, true, 493 pt, ptlim, loc); 494 } 495 continue; 496 case 'v': 497 /* 498 ** From Arnold Robbins' strftime version 3.0: 499 ** "date as dd-bbb-YYYY" 500 ** (ado, 1993-05-24) 501 */ 502 pt = _fmt(sp, "%e-%b-%Y", t, pt, ptlim, warnp, 503 loc); 504 continue; 505 case 'W': 506 pt = _conv((t->tm_yday + DAYSPERWEEK - 507 (t->tm_wday ? 508 (t->tm_wday - 1) : 509 (DAYSPERWEEK - 1))) / DAYSPERWEEK, 510 fmt_padding[PAD_FMT_WEEKOFYEAR][PadIndex], 511 pt, ptlim, loc); 512 continue; 513 case 'w': 514 pt = _conv(t->tm_wday, "%d", pt, ptlim, loc); 515 continue; 516 case 'X': 517 pt = _fmt(sp, tptr->t_fmt, t, pt, 518 ptlim, warnp, loc); 519 continue; 520 case 'x': 521 { 522 enum warn warn2 = IN_SOME; 523 524 pt = _fmt(sp, tptr->d_fmt, t, pt, 525 ptlim, &warn2, loc); 526 if (warn2 == IN_ALL) 527 warn2 = IN_THIS; 528 if (warn2 > *warnp) 529 *warnp = warn2; 530 } 531 continue; 532 case 'y': 533 *warnp = IN_ALL; 534 pt = _yconv(t->tm_year, TM_YEAR_BASE, 535 false, true, 536 pt, ptlim, loc); 537 continue; 538 case 'Y': 539 pt = _yconv(t->tm_year, TM_YEAR_BASE, 540 true, true, 541 pt, ptlim, loc); 542 continue; 543 case 'Z': 544 #ifdef TM_ZONE 545 pt = _add(t->TM_ZONE, pt, ptlim); 546 #elif HAVE_TZNAME 547 if (t->tm_isdst >= 0) { 548 int oerrno = errno, dst = t->tm_isdst; 549 const char *z = 550 tzgetname(sp, dst); 551 if (z == NULL) 552 z = tzgetname(sp, !dst); 553 pt = _add(z ? z : "???", pt, ptlim); 554 errno = oerrno; 555 } 556 #endif 557 /* 558 ** C99 and later say that %Z must be 559 ** replaced by the empty string if the 560 ** time zone abbreviation is not 561 ** determinable. 562 */ 563 continue; 564 case 'z': 565 #if defined TM_GMTOFF || USG_COMPAT || defined ALTZONE 566 { 567 long diff; 568 char const * sign; 569 bool negative; 570 571 if (t->tm_isdst < 0) 572 continue; 573 # ifdef TM_GMTOFF 574 diff = (int)t->TM_GMTOFF; 575 # else 576 /* 577 ** C99 and later say that the UT offset must 578 ** be computed by looking only at 579 ** tm_isdst. This requirement is 580 ** incorrect, since it means the code 581 ** must rely on magic (in this case 582 ** altzone and timezone), and the 583 ** magic might not have the correct 584 ** offset. Doing things correctly is 585 ** tricky and requires disobeying the standard; 586 ** see GNU C strftime for details. 587 ** For now, punt and conform to the 588 ** standard, even though it's incorrect. 589 ** 590 ** C99 and later say that %z must be replaced by 591 ** the empty string if the time zone is not 592 ** determinable, so output nothing if the 593 ** appropriate variables are not available. 594 */ 595 # ifndef STD_INSPIRED 596 if (t->tm_isdst == 0) 597 # if USG_COMPAT 598 diff = -timezone; 599 # else 600 continue; 601 # endif 602 else 603 # ifdef ALTZONE 604 diff = -altzone; 605 # else 606 continue; 607 # endif 608 # else 609 { 610 struct tm tmp; 611 time_t lct, gct; 612 613 /* 614 ** Get calendar time from t 615 ** being treated as local. 616 */ 617 tmp = *t; /* mktime discards const */ 618 lct = mktime_z(sp, &tmp); 619 620 if (lct == (time_t)-1) 621 continue; 622 623 /* 624 ** Get calendar time from t 625 ** being treated as GMT. 626 **/ 627 tmp = *t; /* mktime discards const */ 628 gct = timegm(&tmp); 629 630 if (gct == (time_t)-1) 631 continue; 632 633 /* LINTED difference will fit int */ 634 diff = (intmax_t)gct - (intmax_t)lct; 635 } 636 # endif 637 # endif 638 negative = diff < 0; 639 if (diff == 0) { 640 #ifdef TM_ZONE 641 negative = t->TM_ZONE[0] == '-'; 642 #else 643 negative = t->tm_isdst < 0; 644 # if HAVE_TZNAME 645 if (tzname[t->tm_isdst != 0][0] == '-') 646 negative = true; 647 # endif 648 #endif 649 } 650 if (negative) { 651 sign = "-"; 652 diff = -diff; 653 } else sign = "+"; 654 pt = _add(sign, pt, ptlim); 655 diff /= SECSPERMIN; 656 diff = (diff / MINSPERHOUR) * 100 + 657 (diff % MINSPERHOUR); 658 _DIAGASSERT(__type_fit(int, diff)); 659 pt = _conv((int)diff, 660 fmt_padding[PAD_FMT_YEAR][PadIndex], 661 pt, ptlim, loc); 662 } 663 #endif 664 continue; 665 case '+': 666 #ifdef notyet 667 /* XXX: no date_fmt in _TimeLocale */ 668 pt = _fmt(sp, tptr->date_fmt, t, 669 pt, ptlim, warnp, loc); 670 #else 671 pt = _fmt(sp, "%a %b %e %H:%M:%S %Z %Y", t, 672 pt, ptlim, warnp, loc); 673 #endif 674 continue; 675 case '-': 676 if (PadIndex != PAD_DEFAULT) 677 break; 678 PadIndex = PAD_LESS; 679 goto label; 680 case '_': 681 if (PadIndex != PAD_DEFAULT) 682 break; 683 PadIndex = PAD_SPACE; 684 goto label; 685 case '0': 686 if (PadIndex != PAD_DEFAULT) 687 break; 688 PadIndex = PAD_ZERO; 689 goto label; 690 case '%': 691 /* 692 ** X311J/88-090 (4.12.3.5): if conversion char is 693 ** undefined, behavior is undefined. Print out the 694 ** character itself as printf(3) also does. 695 */ 696 default: 697 break; 698 } 699 } 700 if (pt == ptlim) 701 break; 702 *pt++ = *format; 703 } 704 return pt; 705 } 706 707 size_t 708 strftime(char *s, size_t maxsize, const char *format, const struct tm *t) 709 { 710 size_t r; 711 712 rwlock_wrlock(&__lcl_lock); 713 tzset_unlocked(); 714 r = strftime_z(__lclptr, s, maxsize, format, t); 715 rwlock_unlock(&__lcl_lock); 716 717 return r; 718 } 719 720 size_t 721 strftime_l(char * __restrict s, size_t maxsize, const char * __restrict format, 722 const struct tm * __restrict t, locale_t loc) 723 { 724 size_t r; 725 726 rwlock_wrlock(&__lcl_lock); 727 tzset_unlocked(); 728 r = strftime_lz(__lclptr, s, maxsize, format, t, loc); 729 rwlock_unlock(&__lcl_lock); 730 731 return r; 732 } 733 734 static char * 735 _conv(int n, const char *format, char *pt, const char *ptlim, locale_t loc) 736 { 737 char buf[INT_STRLEN_MAXIMUM(int) + 1]; 738 739 (void) snprintf_l(buf, sizeof(buf), loc, format, n); 740 return _add(buf, pt, ptlim); 741 } 742 743 static char * 744 _add(const char *str, char *pt, const char *ptlim) 745 { 746 while (pt < ptlim && (*pt = *str++) != '\0') 747 ++pt; 748 return pt; 749 } 750 751 /* 752 ** POSIX and the C Standard are unclear or inconsistent about 753 ** what %C and %y do if the year is negative or exceeds 9999. 754 ** Use the convention that %C concatenated with %y yields the 755 ** same output as %Y, and that %Y contains at least 4 bytes, 756 ** with more only if necessary. 757 */ 758 759 static char * 760 _yconv(int a, int b, bool convert_top, bool convert_yy, 761 char *pt, const char * ptlim, locale_t loc) 762 { 763 int lead; 764 int trail; 765 766 #define DIVISOR 100 767 trail = a % DIVISOR + b % DIVISOR; 768 lead = a / DIVISOR + b / DIVISOR + trail / DIVISOR; 769 trail %= DIVISOR; 770 if (trail < 0 && lead > 0) { 771 trail += DIVISOR; 772 --lead; 773 } else if (lead < 0 && trail > 0) { 774 trail -= DIVISOR; 775 ++lead; 776 } 777 if (convert_top) { 778 if (lead == 0 && trail < 0) 779 pt = _add("-0", pt, ptlim); 780 else pt = _conv(lead, "%02d", pt, ptlim, loc); 781 } 782 if (convert_yy) 783 pt = _conv(((trail < 0) ? -trail : trail), "%02d", pt, ptlim, 784 loc); 785 return pt; 786 } 787
Indexes created Thu Sep 25 08:09:54 GMT 2025