1 /* 2 * Copyright 2010 Nexenta Systems, Inc. All rights reserved. 3 * Copyright (c) 1989 The Regents of the University of California. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms are permitted 7 * provided that the above copyright notice and this paragraph are 8 * duplicated in all such forms and that any documentation, 9 * advertising materials, and other materials related to such 10 * distribution and use acknowledge that the software was developed 11 * by the University of California, Berkeley. The name of the 12 * University may not be used to endorse or promote products derived 13 * from this software without specific prior written permission. 14 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 16 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 17 */ 18 19 #include "lint.h" 20 #include "tzfile.h" 21 #include <fcntl.h> 22 #include <sys/stat.h> 23 #include <string.h> 24 #include <stdio.h> 25 #include "timelocal.h" 26 27 static char *_add(const char *, char *, const char *); 28 static char *_conv(int, const char *, char *, const char *); 29 static char *_fmt(const char *, const struct tm *, char *, const char * const); 30 static char *_yconv(int, int, int, int, char *, const char *); 31 32 extern char *tzname[]; 33 34 #define IN_NONE 0 35 #define IN_SOME 1 36 #define IN_THIS 2 37 #define IN_ALL 3 38 39 #define PAD_DEFAULT 0 40 #define PAD_LESS 1 41 #define PAD_SPACE 2 42 #define PAD_ZERO 3 43 44 static const char *fmt_padding[][4] = { 45 /* DEFAULT, LESS, SPACE, ZERO */ 46 #define PAD_FMT_MONTHDAY 0 47 #define PAD_FMT_HMS 0 48 #define PAD_FMT_CENTURY 0 49 #define PAD_FMT_SHORTYEAR 0 50 #define PAD_FMT_MONTH 0 51 #define PAD_FMT_WEEKOFYEAR 0 52 #define PAD_FMT_DAYOFMONTH 0 53 { "%02d", "%d", "%2d", "%02d" }, 54 #define PAD_FMT_SDAYOFMONTH 1 55 #define PAD_FMT_SHMS 1 56 { "%2d", "%d", "%2d", "%02d" }, 57 #define PAD_FMT_DAYOFYEAR 2 58 { "%03d", "%d", "%3d", "%03d" }, 59 #define PAD_FMT_YEAR 3 60 { "%04d", "%d", "%4d", "%04d" } 61 }; 62 63 64 size_t 65 strftime(char *_RESTRICT_KYWD s, size_t maxsize, 66 const char *_RESTRICT_KYWD format, const struct tm *_RESTRICT_KYWD t) 67 { 68 char *p; 69 70 tzset(); 71 p = _fmt(((format == NULL) ? "%c" : format), t, s, s + maxsize); 72 if (p == s + maxsize) 73 return (0); 74 *p = '\0'; 75 return (p - s); 76 } 77 78 static char * 79 _fmt(const char *format, const struct tm *t, char *pt, const char * const ptlim) 80 { 81 int Ealternative, Oalternative, PadIndex; 82 struct lc_time_T *tptr = __get_current_time_locale(); 83 84 #define PADDING(x) fmt_padding[x][PadIndex] 85 86 for (; *format; ++format) { 87 if (*format == '%') { 88 Ealternative = 0; 89 Oalternative = 0; 90 PadIndex = PAD_DEFAULT; 91 label: 92 switch (*++format) { 93 case '\0': 94 --format; 95 break; 96 case 'A': 97 pt = _add((t->tm_wday < 0 || 98 t->tm_wday >= DAYSPERWEEK) ? 99 "?" : tptr->weekday[t->tm_wday], 100 pt, ptlim); 101 continue; 102 case 'a': 103 pt = _add((t->tm_wday < 0 || 104 t->tm_wday >= DAYSPERWEEK) ? 105 "?" : tptr->wday[t->tm_wday], 106 pt, ptlim); 107 continue; 108 case 'B': 109 pt = _add((t->tm_mon < 0 || 110 t->tm_mon >= MONSPERYEAR) ? 111 "?" : (tptr->month)[t->tm_mon], 112 pt, ptlim); 113 continue; 114 case 'b': 115 case 'h': 116 pt = _add((t->tm_mon < 0 || 117 t->tm_mon >= MONSPERYEAR) ? 118 "?" : tptr->mon[t->tm_mon], 119 pt, ptlim); 120 continue; 121 case 'C': 122 /* 123 * %C used to do a... 124 * _fmt("%a %b %e %X %Y", t); 125 * ...whereas now POSIX 1003.2 calls for 126 * something completely different. 127 * (ado, 1993-05-24) 128 */ 129 pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 0, 130 pt, ptlim); 131 continue; 132 case 'c': 133 pt = _fmt(tptr->c_fmt, t, pt, ptlim); 134 continue; 135 case 'D': 136 pt = _fmt("%m/%d/%y", t, pt, ptlim); 137 continue; 138 case 'd': 139 pt = _conv(t->tm_mday, 140 PADDING(PAD_FMT_DAYOFMONTH), pt, ptlim); 141 continue; 142 case 'E': 143 if (Ealternative || Oalternative) 144 break; 145 Ealternative++; 146 goto label; 147 case 'O': 148 /* 149 * C99 locale modifiers. 150 * The sequences 151 * %Ec %EC %Ex %EX %Ey %EY 152 * %Od %oe %OH %OI %Om %OM 153 * %OS %Ou %OU %OV %Ow %OW %Oy 154 * are supposed to provide alternate 155 * representations. 156 */ 157 if (Ealternative || Oalternative) 158 break; 159 Oalternative++; 160 goto label; 161 case 'e': 162 pt = _conv(t->tm_mday, 163 PADDING(PAD_FMT_SDAYOFMONTH), pt, ptlim); 164 continue; 165 case 'F': 166 pt = _fmt("%Y-%m-%d", t, pt, ptlim); 167 continue; 168 case 'H': 169 pt = _conv(t->tm_hour, PADDING(PAD_FMT_HMS), 170 pt, ptlim); 171 continue; 172 case 'I': 173 pt = _conv((t->tm_hour % 12) ? 174 (t->tm_hour % 12) : 12, 175 PADDING(PAD_FMT_HMS), pt, ptlim); 176 continue; 177 case 'j': 178 pt = _conv(t->tm_yday + 1, 179 PADDING(PAD_FMT_DAYOFYEAR), pt, ptlim); 180 continue; 181 case 'k': 182 /* 183 * This used to be... 184 * _conv(t->tm_hour % 12 ? 185 * t->tm_hour % 12 : 12, 2, ' '); 186 * ...and has been changed to the below to 187 * match SunOS 4.1.1 and Arnold Robbins' 188 * strftime version 3.0. That is, "%k" and 189 * "%l" have been swapped. 190 * (ado, 1993-05-24) 191 */ 192 pt = _conv(t->tm_hour, 193 PADDING(PAD_FMT_SHMS), pt, ptlim); 194 continue; 195 case 'l': 196 /* 197 * This used to be... 198 * _conv(t->tm_hour, 2, ' '); 199 * ...and has been changed to the below to 200 * match SunOS 4.1.1 and Arnold Robbin's 201 * strftime version 3.0. That is, "%k" and 202 * "%l" have been swapped. 203 * (ado, 1993-05-24) 204 */ 205 pt = _conv((t->tm_hour % 12) ? 206 (t->tm_hour % 12) : 12, 207 PADDING(PAD_FMT_SHMS), pt, ptlim); 208 continue; 209 case 'M': 210 pt = _conv(t->tm_min, PADDING(PAD_FMT_HMS), 211 pt, ptlim); 212 continue; 213 case 'm': 214 pt = _conv(t->tm_mon + 1, 215 PADDING(PAD_FMT_MONTH), 216 pt, ptlim); 217 continue; 218 case 'n': 219 pt = _add("\n", pt, ptlim); 220 continue; 221 case 'p': 222 pt = _add((t->tm_hour >= (HOURSPERDAY / 2)) ? 223 tptr->pm : tptr->am, pt, ptlim); 224 continue; 225 case 'R': 226 pt = _fmt("%H:%M", t, pt, ptlim); 227 continue; 228 case 'r': 229 pt = _fmt(tptr->ampm_fmt, t, pt, ptlim); 230 continue; 231 case 'S': 232 pt = _conv(t->tm_sec, PADDING(PAD_FMT_HMS), 233 pt, ptlim); 234 continue; 235 236 case 's': 237 { 238 struct tm tm; 239 char *buf; 240 241 tm = *t; 242 (void) asprintf(&buf, "%ld", mktime(&tm)); 243 pt = _add(buf, pt, ptlim); 244 continue; 245 } 246 247 case 'T': 248 pt = _fmt("%H:%M:%S", t, pt, ptlim); 249 continue; 250 case 't': 251 pt = _add("\t", pt, ptlim); 252 continue; 253 case 'U': 254 pt = _conv((t->tm_yday + DAYSPERWEEK - 255 t->tm_wday) / DAYSPERWEEK, 256 PADDING(PAD_FMT_WEEKOFYEAR), 257 pt, ptlim); 258 continue; 259 case 'u': 260 /* 261 * From Arnold Robbins' strftime version 3.0: 262 * "ISO 8601: Weekday as a decimal number 263 * [1 (Monday) - 7]" 264 * (ado, 1993-05-24) 265 */ 266 pt = _conv((t->tm_wday == 0) ? 267 DAYSPERWEEK : t->tm_wday, 268 "%d", pt, ptlim); 269 continue; 270 case 'V': /* ISO 8601 week number */ 271 case 'G': /* ISO 8601 year (four digits) */ 272 case 'g': /* ISO 8601 year (two digits) */ 273 /* 274 * From Arnold Robbins' strftime version 3.0: "the week number of the 275 * year (the first Monday as the first day of week 1) as a decimal number 276 * (01-53)." 277 * (ado, 1993-05-24) 278 * 279 * From "http://www.ft.uni-erlangen.de/~mskuhn/iso-time.html" by Markus Kuhn: 280 * "Week 01 of a year is per definition the first week which has the 281 * Thursday in this year, which is equivalent to the week which contains 282 * the fourth day of January. In other words, the first week of a new year 283 * is the week which has the majority of its days in the new year. Week 01 284 * might also contain days from the previous year and the week before week 285 * 01 of a year is the last week (52 or 53) of the previous year even if 286 * it contains days from the new year. A week starts with Monday (day 1) 287 * and ends with Sunday (day 7). For example, the first week of the year 288 * 1997 lasts from 1996-12-30 to 1997-01-05..." 289 * (ado, 1996-01-02) 290 */ 291 { 292 int year; 293 int base; 294 int yday; 295 int wday; 296 int w; 297 298 year = t->tm_year; 299 base = TM_YEAR_BASE; 300 yday = t->tm_yday; 301 wday = t->tm_wday; 302 for (;;) { 303 int len; 304 int bot; 305 int top; 306 307 len = isleap_sum(year, base) ? 308 DAYSPERLYEAR : DAYSPERNYEAR; 309 /* 310 * What yday (-3 ... 3) does 311 * the ISO year begin on? 312 */ 313 bot = ((yday + 11 - wday) % 314 DAYSPERWEEK) - 3; 315 /* 316 * What yday does the NEXT 317 * ISO year begin on? 318 */ 319 top = bot - (len % DAYSPERWEEK); 320 if (top < -3) 321 top += DAYSPERWEEK; 322 top += len; 323 if (yday >= top) { 324 ++base; 325 w = 1; 326 break; 327 } 328 if (yday >= bot) { 329 w = 1 + ((yday - bot) / 330 DAYSPERWEEK); 331 break; 332 } 333 --base; 334 yday += isleap_sum(year, base) ? 335 DAYSPERLYEAR : DAYSPERNYEAR; 336 } 337 #ifdef XPG4_1994_04_09 338 if ((w == 52 && t->tm_mon == TM_JANUARY) || 339 (w == 1 && t->tm_mon == TM_DECEMBER)) 340 w = 53; 341 #endif /* defined XPG4_1994_04_09 */ 342 if (*format == 'V') 343 pt = _conv(w, 344 PADDING(PAD_FMT_WEEKOFYEAR), 345 pt, ptlim); 346 else if (*format == 'g') { 347 pt = _yconv(year, base, 0, 1, 348 pt, ptlim); 349 } else 350 pt = _yconv(year, base, 1, 1, 351 pt, ptlim); 352 } 353 continue; 354 case 'v': 355 /* 356 * From Arnold Robbins' strftime version 3.0: 357 * "date as dd-bbb-YYYY" 358 * (ado, 1993-05-24) 359 */ 360 pt = _fmt("%e-%b-%Y", t, pt, ptlim); 361 continue; 362 case 'W': 363 pt = _conv((t->tm_yday + DAYSPERWEEK - 364 (t->tm_wday ? 365 (t->tm_wday - 1) : 366 (DAYSPERWEEK - 1))) / DAYSPERWEEK, 367 PADDING(PAD_FMT_WEEKOFYEAR), 368 pt, ptlim); 369 continue; 370 case 'w': 371 pt = _conv(t->tm_wday, "%d", pt, ptlim); 372 continue; 373 case 'X': 374 pt = _fmt(tptr->X_fmt, t, pt, ptlim); 375 continue; 376 case 'x': 377 pt = _fmt(tptr->x_fmt, t, pt, ptlim); 378 continue; 379 case 'y': 380 pt = _yconv(t->tm_year, TM_YEAR_BASE, 0, 1, 381 pt, ptlim); 382 continue; 383 case 'Y': 384 pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 1, 385 pt, ptlim); 386 continue; 387 case 'Z': 388 if (t->tm_isdst >= 0) 389 pt = _add(tzname[t->tm_isdst != 0], 390 pt, ptlim); 391 /* 392 * C99 says that %Z must be replaced by the 393 * empty string if the time zone is not 394 * determinable. 395 */ 396 continue; 397 case 'z': 398 { 399 int diff; 400 char const * sign; 401 402 if (t->tm_isdst < 0) 403 continue; 404 /* 405 * C99 says that the UTC offset must 406 * be computed by looking only at 407 * tm_isdst. This requirement is 408 * incorrect, since it means the code 409 * must rely on magic (in this case 410 * altzone and timezone), and the 411 * magic might not have the correct 412 * offset. Doing things correctly is 413 * tricky and requires disobeying C99; 414 * see GNU C strftime for details. 415 * For now, punt and conform to the 416 * standard, even though it's incorrect. 417 * 418 * C99 says that %z must be replaced by the 419 * empty string if the time zone is not 420 * determinable, so output nothing if the 421 * appropriate variables are not available. 422 */ 423 if (t->tm_isdst == 0) 424 diff = -timezone; 425 else 426 diff = -altzone; 427 if (diff < 0) { 428 sign = "-"; 429 diff = -diff; 430 } else 431 sign = "+"; 432 pt = _add(sign, pt, ptlim); 433 diff /= SECSPERMIN; 434 diff = (diff / MINSPERHOUR) * 100 + 435 (diff % MINSPERHOUR); 436 pt = _conv(diff, PADDING(PAD_FMT_YEAR), 437 pt, ptlim); 438 } 439 continue; 440 case '+': 441 pt = _fmt(tptr->date_fmt, t, pt, ptlim); 442 continue; 443 case '-': 444 if (PadIndex != PAD_DEFAULT) 445 break; 446 PadIndex = PAD_LESS; 447 goto label; 448 case '_': 449 if (PadIndex != PAD_DEFAULT) 450 break; 451 PadIndex = PAD_SPACE; 452 goto label; 453 case '0': 454 if (PadIndex != PAD_DEFAULT) 455 break; 456 PadIndex = PAD_ZERO; 457 goto label; 458 case '%': 459 /* 460 * X311J/88-090 (4.12.3.5): if conversion char is 461 * undefined, behavior is undefined. Print out the 462 * character itself as printf(3) also does. 463 */ 464 default: 465 break; 466 } 467 } 468 if (pt == ptlim) 469 break; 470 *pt++ = *format; 471 } 472 return (pt); 473 } 474 475 static char * 476 _conv(const int n, const char *format, char *const pt, 477 const char *const ptlim) 478 { 479 char buf[12]; 480 481 (void) sprintf(buf, format, n); 482 return (_add(buf, pt, ptlim)); 483 } 484 485 static char * 486 _add(const char *str, char *pt, const char *const ptlim) 487 { 488 while (pt < ptlim && (*pt = *str++) != '\0') 489 ++pt; 490 return (pt); 491 } 492 493 /* 494 * POSIX and the C Standard are unclear or inconsistent about 495 * what %C and %y do if the year is negative or exceeds 9999. 496 * Use the convention that %C concatenated with %y yields the 497 * same output as %Y, and that %Y contains at least 4 bytes, 498 * with more only if necessary. 499 */ 500 501 static char * 502 _yconv(const int a, const int b, const int convert_top, const int convert_yy, 503 char *pt, const char * const ptlim) 504 { 505 register int lead; 506 register int trail; 507 508 #define DIVISOR 100 509 trail = a % DIVISOR + b % DIVISOR; 510 lead = a / DIVISOR + b / DIVISOR + trail / DIVISOR; 511 trail %= DIVISOR; 512 if (trail < 0 && lead > 0) { 513 trail += DIVISOR; 514 --lead; 515 } else if (lead < 0 && trail > 0) { 516 trail -= DIVISOR; 517 ++lead; 518 } 519 if (convert_top) { 520 if (lead == 0 && trail < 0) 521 pt = _add("-0", pt, ptlim); 522 else pt = _conv(lead, "%02d", pt, ptlim); 523 } 524 if (convert_yy) 525 pt = _conv(((trail < 0) ? -trail : trail), "%02d", pt, ptlim); 526 return (pt); 527 } 528