strftime.c revision 1.26 1 /* $NetBSD: strftime.c,v 1.26 2013/05/17 12:55:57 joerg Exp $ */
2
3 #include <sys/cdefs.h>
4 #if defined(LIBC_SCCS) && !defined(lint)
5 #if 0
6 static char elsieid[] = "@(#)strftime.c 7.64";
7 static char elsieid[] = "@(#)strftime.c 8.3";
8 #else
9 __RCSID("$NetBSD: strftime.c,v 1.26 2013/05/17 12:55:57 joerg Exp $");
10 #endif
11 #endif /* LIBC_SCCS and not lint */
12
13 #include "namespace.h"
14
15 #include <stddef.h>
16 #include <locale.h>
17 #include "setlocale_local.h"
18
19 /*
20 ** Based on the UCB version with the copyright notice and sccsid
21 ** appearing below.
22 **
23 ** This is ANSIish only when "multibyte character == plain character".
24 */
25
26 #include "private.h"
27
28 /*
29 ** We don't use these extensions in strftime operation even when
30 ** supported by the local tzcode configuration. A strictly
31 ** conforming C application may leave them in undefined state.
32 */
33
34 #ifdef _LIBC
35 #undef TM_ZONE
36 #undef TM_GMTOFF
37 #endif
38
39 /*
40 ** Copyright (c) 1989, 1993
41 ** The Regents of the University of California. All rights reserved.
42 **
43 ** Redistribution and use in source and binary forms, with or without
44 ** modification, are permitted provided that the following conditions
45 ** are met:
46 ** 1. Redistributions of source code must retain the above copyright
47 ** notice, this list of conditions and the following disclaimer.
48 ** 2. Redistributions in binary form must reproduce the above copyright
49 ** notice, this list of conditions and the following disclaimer in the
50 ** documentation and/or other materials provided with the distribution.
51 ** 3. All advertising materials mentioning features or use of this software
52 ** must display the following acknowledgement:
53 ** This product includes software developed by the University of
54 ** California, Berkeley and its contributors.
55 ** 4. Neither the name of the University nor the names of its contributors
56 ** may be used to endorse or promote products derived from this software
57 ** without specific prior written permission.
58 **
59 ** THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60 ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61 ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62 ** ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63 ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64 ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65 ** OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66 ** HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68 ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69 ** SUCH DAMAGE.
70 */
71
72 #ifndef LIBC_SCCS
73 #ifndef lint
74 static const char sccsid[] = "@(#)strftime.c 5.4 (Berkeley) 3/14/89";
75 #endif /* !defined lint */
76 #endif /* !defined LIBC_SCCS */
77
78 #include "tzfile.h"
79 #include "fcntl.h"
80 #include "locale.h"
81
82 #ifdef __weak_alias
83 __weak_alias(strftime_l, _strftime_l)
84 __weak_alias(strftime_lz, _strftime_lz)
85 __weak_alias(strftime_z, _strftime_z)
86 #endif
87
88 #include "sys/localedef.h"
89 #define _TIME_LOCALE(loc) \
90 ((_TimeLocale *)((loc)->part_impl[(size_t)LC_TIME]))
91 #define c_fmt d_t_fmt
92
93 static char * _add(const char *, char *, const char *);
94 static char * _conv(int, const char *, char *, const char *);
95 static char * _fmt(const timezone_t, const char *, const struct tm *, char *,
96 const char *, int *, locale_t);
97 static char * _yconv(int, int, int, int, char *, const char *);
98
99 extern char * tzname[];
100
101 #ifndef YEAR_2000_NAME
102 #define YEAR_2000_NAME "CHECK_STRFTIME_FORMATS_FOR_TWO_DIGIT_YEARS"
103 #endif /* !defined YEAR_2000_NAME */
104
105 #define IN_NONE 0
106 #define IN_SOME 1
107 #define IN_THIS 2
108 #define IN_ALL 3
109
110 size_t
111 strftime_z(const timezone_t sp, char * __restrict s, size_t maxsize,
112 const char * __restrict format, const struct tm * __restrict t)
113 {
114 return strftime_lz(sp, s, maxsize, format, t, _current_locale());
115 }
116
117 size_t
118 strftime_lz(const timezone_t sp, char *const s, const size_t maxsize,
119 const char *const format, const struct tm *const t, locale_t loc)
120 {
121 char * p;
122 int warn;
123
124 warn = IN_NONE;
125 p = _fmt(sp, ((format == NULL) ? "%c" : format), t, s, s + maxsize,
126 &warn, loc);
127 #ifndef NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU
128 if (warn != IN_NONE && getenv(YEAR_2000_NAME) != NULL) {
129 (void) fprintf(stderr, "\n");
130 if (format == NULL)
131 (void) fprintf(stderr, "NULL strftime format ");
132 else (void) fprintf(stderr, "strftime format \"%s\" ",
133 format);
134 (void) fprintf(stderr, "yields only two digits of years in ");
135 if (warn == IN_SOME)
136 (void) fprintf(stderr, "some locales");
137 else if (warn == IN_THIS)
138 (void) fprintf(stderr, "the current locale");
139 else (void) fprintf(stderr, "all locales");
140 (void) fprintf(stderr, "\n");
141 }
142 #endif /* !defined NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU */
143 if (p == s + maxsize)
144 return 0;
145 *p = '\0';
146 return p - s;
147 }
148
149 static char *
150 _fmt(const timezone_t sp, const char *format, const struct tm *const t,
151 char *pt, const char *const ptlim, int *warnp, locale_t loc)
152 {
153 for ( ; *format; ++format) {
154 if (*format == '%') {
155 label:
156 switch (*++format) {
157 case '\0':
158 --format;
159 break;
160 case 'A':
161 pt = _add((t->tm_wday < 0 ||
162 t->tm_wday >= DAYSPERWEEK) ?
163 "?" : _TIME_LOCALE(loc)->day[t->tm_wday],
164 pt, ptlim);
165 continue;
166 case 'a':
167 pt = _add((t->tm_wday < 0 ||
168 t->tm_wday >= DAYSPERWEEK) ?
169 "?" : _TIME_LOCALE(loc)->abday[t->tm_wday],
170 pt, ptlim);
171 continue;
172 case 'B':
173 pt = _add((t->tm_mon < 0 ||
174 t->tm_mon >= MONSPERYEAR) ?
175 "?" : _TIME_LOCALE(loc)->mon[t->tm_mon],
176 pt, ptlim);
177 continue;
178 case 'b':
179 case 'h':
180 pt = _add((t->tm_mon < 0 ||
181 t->tm_mon >= MONSPERYEAR) ?
182 "?" : _TIME_LOCALE(loc)->abmon[t->tm_mon],
183 pt, ptlim);
184 continue;
185 case 'C':
186 /*
187 ** %C used to do a...
188 ** _fmt("%a %b %e %X %Y", t);
189 ** ...whereas now POSIX 1003.2 calls for
190 ** something completely different.
191 ** (ado, 1993-05-24)
192 */
193 pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 0,
194 pt, ptlim);
195 continue;
196 case 'c':
197 {
198 int warn2 = IN_SOME;
199
200 pt = _fmt(sp, _TIME_LOCALE(loc)->c_fmt, t, pt,
201 ptlim, &warn2, loc);
202 if (warn2 == IN_ALL)
203 warn2 = IN_THIS;
204 if (warn2 > *warnp)
205 *warnp = warn2;
206 }
207 continue;
208 case 'D':
209 pt = _fmt(sp, "%m/%d/%y", t, pt, ptlim, warnp,
210 loc);
211 continue;
212 case 'd':
213 pt = _conv(t->tm_mday, "%02d", pt, ptlim);
214 continue;
215 case 'E':
216 case 'O':
217 /*
218 ** C99 locale modifiers.
219 ** The sequences
220 ** %Ec %EC %Ex %EX %Ey %EY
221 ** %Od %oe %OH %OI %Om %OM
222 ** %OS %Ou %OU %OV %Ow %OW %Oy
223 ** are supposed to provide alternate
224 ** representations.
225 */
226 goto label;
227 case 'e':
228 pt = _conv(t->tm_mday, "%2d", pt, ptlim);
229 continue;
230 case 'F':
231 pt = _fmt(sp, "%Y-%m-%d", t, pt, ptlim, warnp,
232 loc);
233 continue;
234 case 'H':
235 pt = _conv(t->tm_hour, "%02d", pt, ptlim);
236 continue;
237 case 'I':
238 pt = _conv((t->tm_hour % 12) ?
239 (t->tm_hour % 12) : 12,
240 "%02d", pt, ptlim);
241 continue;
242 case 'j':
243 pt = _conv(t->tm_yday + 1, "%03d", pt, ptlim);
244 continue;
245 case 'k':
246 /*
247 ** This used to be...
248 ** _conv(t->tm_hour % 12 ?
249 ** t->tm_hour % 12 : 12, 2, ' ');
250 ** ...and has been changed to the below to
251 ** match SunOS 4.1.1 and Arnold Robbins'
252 ** strftime version 3.0. That is, "%k" and
253 ** "%l" have been swapped.
254 ** (ado, 1993-05-24)
255 */
256 pt = _conv(t->tm_hour, "%2d", pt, ptlim);
257 continue;
258 #ifdef KITCHEN_SINK
259 case 'K':
260 /*
261 ** After all this time, still unclaimed!
262 */
263 pt = _add("kitchen sink", pt, ptlim);
264 continue;
265 #endif /* defined KITCHEN_SINK */
266 case 'l':
267 /*
268 ** This used to be...
269 ** _conv(t->tm_hour, 2, ' ');
270 ** ...and has been changed to the below to
271 ** match SunOS 4.1.1 and Arnold Robbin's
272 ** strftime version 3.0. That is, "%k" and
273 ** "%l" have been swapped.
274 ** (ado, 1993-05-24)
275 */
276 pt = _conv((t->tm_hour % 12) ?
277 (t->tm_hour % 12) : 12,
278 "%2d", pt, ptlim);
279 continue;
280 case 'M':
281 pt = _conv(t->tm_min, "%02d", pt, ptlim);
282 continue;
283 case 'm':
284 pt = _conv(t->tm_mon + 1, "%02d", pt, ptlim);
285 continue;
286 case 'n':
287 pt = _add("\n", pt, ptlim);
288 continue;
289 case 'p':
290 pt = _add((t->tm_hour >= (HOURSPERDAY / 2)) ?
291 _TIME_LOCALE(loc)->am_pm[1] :
292 _TIME_LOCALE(loc)->am_pm[0],
293 pt, ptlim);
294 continue;
295 case 'R':
296 pt = _fmt(sp, "%H:%M", t, pt, ptlim, warnp,
297 loc);
298 continue;
299 case 'r':
300 pt = _fmt(sp, _TIME_LOCALE(loc)->t_fmt_ampm, t,
301 pt, ptlim, warnp, loc);
302 continue;
303 case 'S':
304 pt = _conv(t->tm_sec, "%02d", pt, ptlim);
305 continue;
306 case 's':
307 {
308 struct tm tm;
309 char buf[INT_STRLEN_MAXIMUM(
310 time_t) + 1];
311 time_t mkt;
312
313 tm = *t;
314 mkt = mktime(&tm);
315 /* CONSTCOND */
316 if (TYPE_SIGNED(time_t))
317 (void) snprintf(buf, sizeof(buf),
318 "%lld", (long long) mkt);
319 else (void) snprintf(buf, sizeof(buf),
320 "%llu", (unsigned long long)
321 mkt);
322 pt = _add(buf, pt, ptlim);
323 }
324 continue;
325 case 'T':
326 pt = _fmt(sp, "%H:%M:%S", t, pt, ptlim, warnp,
327 loc);
328 continue;
329 case 't':
330 pt = _add("\t", pt, ptlim);
331 continue;
332 case 'U':
333 pt = _conv((t->tm_yday + DAYSPERWEEK -
334 t->tm_wday) / DAYSPERWEEK,
335 "%02d", pt, ptlim);
336 continue;
337 case 'u':
338 /*
339 ** From Arnold Robbins' strftime version 3.0:
340 ** "ISO 8601: Weekday as a decimal number
341 ** [1 (Monday) - 7]"
342 ** (ado, 1993-05-24)
343 */
344 pt = _conv((t->tm_wday == 0) ?
345 DAYSPERWEEK : t->tm_wday,
346 "%d", pt, ptlim);
347 continue;
348 case 'V': /* ISO 8601 week number */
349 case 'G': /* ISO 8601 year (four digits) */
350 case 'g': /* ISO 8601 year (two digits) */
351 /*
352 ** From Arnold Robbins' strftime version 3.0: "the week number of the
353 ** year (the first Monday as the first day of week 1) as a decimal number
354 ** (01-53)."
355 ** (ado, 1993-05-24)
356 **
357 ** From "http://www.ft.uni-erlangen.de/~mskuhn/iso-time.html" by Markus Kuhn:
358 ** "Week 01 of a year is per definition the first week which has the
359 ** Thursday in this year, which is equivalent to the week which contains
360 ** the fourth day of January. In other words, the first week of a new year
361 ** is the week which has the majority of its days in the new year. Week 01
362 ** might also contain days from the previous year and the week before week
363 ** 01 of a year is the last week (52 or 53) of the previous year even if
364 ** it contains days from the new year. A week starts with Monday (day 1)
365 ** and ends with Sunday (day 7). For example, the first week of the year
366 ** 1997 lasts from 1996-12-30 to 1997-01-05..."
367 ** (ado, 1996-01-02)
368 */
369 {
370 int year;
371 int base;
372 int yday;
373 int wday;
374 int w;
375
376 year = t->tm_year;
377 base = TM_YEAR_BASE;
378 yday = t->tm_yday;
379 wday = t->tm_wday;
380 for ( ; ; ) {
381 int len;
382 int bot;
383 int top;
384
385 len = isleap_sum(year, base) ?
386 DAYSPERLYEAR :
387 DAYSPERNYEAR;
388 /*
389 ** What yday (-3 ... 3) does
390 ** the ISO year begin on?
391 */
392 bot = ((yday + 11 - wday) %
393 DAYSPERWEEK) - 3;
394 /*
395 ** What yday does the NEXT
396 ** ISO year begin on?
397 */
398 top = bot -
399 (len % DAYSPERWEEK);
400 if (top < -3)
401 top += DAYSPERWEEK;
402 top += len;
403 if (yday >= top) {
404 ++base;
405 w = 1;
406 break;
407 }
408 if (yday >= bot) {
409 w = 1 + ((yday - bot) /
410 DAYSPERWEEK);
411 break;
412 }
413 --base;
414 yday += isleap_sum(year, base) ?
415 DAYSPERLYEAR :
416 DAYSPERNYEAR;
417 }
418 #ifdef XPG4_1994_04_09
419 if ((w == 52 &&
420 t->tm_mon == TM_JANUARY) ||
421 (w == 1 &&
422 t->tm_mon == TM_DECEMBER))
423 w = 53;
424 #endif /* defined XPG4_1994_04_09 */
425 if (*format == 'V')
426 pt = _conv(w, "%02d",
427 pt, ptlim);
428 else if (*format == 'g') {
429 *warnp = IN_ALL;
430 pt = _yconv(year, base, 0, 1,
431 pt, ptlim);
432 } else pt = _yconv(year, base, 1, 1,
433 pt, ptlim);
434 }
435 continue;
436 case 'v':
437 /*
438 ** From Arnold Robbins' strftime version 3.0:
439 ** "date as dd-bbb-YYYY"
440 ** (ado, 1993-05-24)
441 */
442 pt = _fmt(sp, "%e-%b-%Y", t, pt, ptlim, warnp,
443 loc);
444 continue;
445 case 'W':
446 pt = _conv((t->tm_yday + DAYSPERWEEK -
447 (t->tm_wday ?
448 (t->tm_wday - 1) :
449 (DAYSPERWEEK - 1))) / DAYSPERWEEK,
450 "%02d", pt, ptlim);
451 continue;
452 case 'w':
453 pt = _conv(t->tm_wday, "%d", pt, ptlim);
454 continue;
455 case 'X':
456 pt = _fmt(sp, _TIME_LOCALE(loc)->t_fmt, t, pt,
457 ptlim, warnp, loc);
458 continue;
459 case 'x':
460 {
461 int warn2 = IN_SOME;
462
463 pt = _fmt(sp, _TIME_LOCALE(loc)->d_fmt, t, pt,
464 ptlim, &warn2, loc);
465 if (warn2 == IN_ALL)
466 warn2 = IN_THIS;
467 if (warn2 > *warnp)
468 *warnp = warn2;
469 }
470 continue;
471 case 'y':
472 *warnp = IN_ALL;
473 pt = _yconv(t->tm_year, TM_YEAR_BASE, 0, 1,
474 pt, ptlim);
475 continue;
476 case 'Y':
477 pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 1,
478 pt, ptlim);
479 continue;
480 case 'Z':
481 #ifdef TM_ZONE
482 if (t->TM_ZONE != NULL)
483 pt = _add(t->TM_ZONE, pt, ptlim);
484 else
485 #endif /* defined TM_ZONE */
486 if (t->tm_isdst >= 0)
487 pt = _add((sp ?
488 tzgetname(sp, t->tm_isdst) :
489 tzname[t->tm_isdst != 0]),
490 pt, ptlim);
491 /*
492 ** C99 says that %Z must be replaced by the
493 ** empty string if the time zone is not
494 ** determinable.
495 */
496 continue;
497 case 'z':
498 {
499 int diff;
500 char const * sign;
501
502 if (t->tm_isdst < 0)
503 continue;
504 #ifdef TM_GMTOFF
505 diff = (int)t->TM_GMTOFF;
506 #else /* !defined TM_GMTOFF */
507 /*
508 ** C99 says that the UTC offset must
509 ** be computed by looking only at
510 ** tm_isdst. This requirement is
511 ** incorrect, since it means the code
512 ** must rely on magic (in this case
513 ** altzone and timezone), and the
514 ** magic might not have the correct
515 ** offset. Doing things correctly is
516 ** tricky and requires disobeying C99;
517 ** see GNU C strftime for details.
518 ** For now, punt and conform to the
519 ** standard, even though it's incorrect.
520 **
521 ** C99 says that %z must be replaced by the
522 ** empty string if the time zone is not
523 ** determinable, so output nothing if the
524 ** appropriate variables are not available.
525 */
526 #ifndef STD_INSPIRED
527 if (t->tm_isdst == 0)
528 #ifdef USG_COMPAT
529 diff = -timezone;
530 #else /* !defined USG_COMPAT */
531 continue;
532 #endif /* !defined USG_COMPAT */
533 else
534 #ifdef ALTZONE
535 diff = -altzone;
536 #else /* !defined ALTZONE */
537 continue;
538 #endif /* !defined ALTZONE */
539 #else /* defined STD_INSPIRED */
540 {
541 struct tm tmp;
542 time_t lct, gct;
543
544 /*
545 ** Get calendar time from t
546 ** being treated as local.
547 */
548 tmp = *t; /* mktime discards const */
549 lct = mktime(&tmp);
550
551 if (lct == (time_t)-1)
552 continue;
553
554 /*
555 ** Get calendar time from t
556 ** being treated as GMT.
557 **/
558 tmp = *t; /* mktime discards const */
559 gct = timegm(&tmp);
560
561 if (gct == (time_t)-1)
562 continue;
563
564 /* LINTED difference will fit int */
565 diff = (intmax_t)gct - (intmax_t)lct;
566 }
567 #endif /* defined STD_INSPIRED */
568 #endif /* !defined TM_GMTOFF */
569 if (diff < 0) {
570 sign = "-";
571 diff = -diff;
572 } else sign = "+";
573 pt = _add(sign, pt, ptlim);
574 diff /= SECSPERMIN;
575 diff = (diff / MINSPERHOUR) * 100 +
576 (diff % MINSPERHOUR);
577 pt = _conv(diff, "%04d", pt, ptlim);
578 }
579 continue;
580 #if 0
581 case '+':
582 pt = _fmt(sp, _TIME_LOCALE(loc)->date_fmt, t,
583 pt, ptlim, warnp, loc);
584 continue;
585 #endif
586 case '%':
587 /*
588 ** X311J/88-090 (4.12.3.5): if conversion char is
589 ** undefined, behavior is undefined. Print out the
590 ** character itself as printf(3) also does.
591 */
592 default:
593 break;
594 }
595 }
596 if (pt == ptlim)
597 break;
598 *pt++ = *format;
599 }
600 return pt;
601 }
602
603 size_t
604 strftime(char * const s, const size_t maxsize,
605 const char * const format, const struct tm * const t)
606 {
607 tzset();
608 return strftime_z(NULL, s, maxsize, format, t);
609 }
610
611 size_t
612 strftime_l(char * __restrict s, size_t maxsize, const char * __restrict format,
613 const struct tm * __restrict t, locale_t loc)
614 {
615 tzset();
616 return strftime_lz(NULL, s, maxsize, format, t, loc);
617 }
618
619 static char *
620 _conv(const int n, const char *const format, char *const pt,
621 const char *const ptlim)
622 {
623 char buf[INT_STRLEN_MAXIMUM(int) + 1];
624
625 (void) snprintf(buf, sizeof(buf), format, n);
626 return _add(buf, pt, ptlim);
627 }
628
629 static char *
630 _add(const char *str, char *pt, const char *const ptlim)
631 {
632 while (pt < ptlim && (*pt = *str++) != '\0')
633 ++pt;
634 return pt;
635 }
636
637 /*
638 ** POSIX and the C Standard are unclear or inconsistent about
639 ** what %C and %y do if the year is negative or exceeds 9999.
640 ** Use the convention that %C concatenated with %y yields the
641 ** same output as %Y, and that %Y contains at least 4 bytes,
642 ** with more only if necessary.
643 */
644
645 static char *
646 _yconv(const int a, const int b, const int convert_top, const int convert_yy,
647 char *pt, const char *const ptlim)
648 {
649 register int lead;
650 register int trail;
651
652 #define DIVISOR 100
653 trail = a % DIVISOR + b % DIVISOR;
654 lead = a / DIVISOR + b / DIVISOR + trail / DIVISOR;
655 trail %= DIVISOR;
656 if (trail < 0 && lead > 0) {
657 trail += DIVISOR;
658 --lead;
659 } else if (lead < 0 && trail > 0) {
660 trail -= DIVISOR;
661 ++lead;
662 }
663 if (convert_top) {
664 if (lead == 0 && trail < 0)
665 pt = _add("-0", pt, ptlim);
666 else pt = _conv(lead, "%02d", pt, ptlim);
667 }
668 if (convert_yy)
669 pt = _conv(((trail < 0) ? -trail : trail), "%02d", pt, ptlim);
670 return pt;
671 }
672
673 #ifdef LOCALE_HOME
674 static struct lc_time_T *
675 _loc(void)
676 {
677 static const char locale_home[] = LOCALE_HOME;
678 static const char lc_time[] = "LC_TIME";
679 static char * locale_buf;
680
681 int fd;
682 int oldsun; /* "...ain't got nothin' to do..." */
683 char * lbuf;
684 char * name;
685 char * p;
686 const char ** ap;
687 const char * plim;
688 char filename[FILENAME_MAX];
689 struct stat st;
690 size_t namesize;
691 size_t bufsize;
692
693 /*
694 ** Use localebuf.mon[0] to signal whether locale is already set up.
695 */
696 if (localebuf.mon[0])
697 return &localebuf;
698 name = setlocale(LC_TIME, NULL);
699 if (name == NULL || *name == '\0')
700 goto no_locale;
701 /*
702 ** If the locale name is the same as our cache, use the cache.
703 */
704 lbuf = locale_buf;
705 if (lbuf != NULL && strcmp(name, lbuf) == 0) {
706 p = lbuf;
707 for (ap = (const char **) &localebuf;
708 ap < (const char **) (&localebuf + 1);
709 ++ap)
710 *ap = p += strlen(p) + 1;
711 return &localebuf;
712 }
713 /*
714 ** Slurp the locale file into the cache.
715 */
716 namesize = strlen(name) + 1;
717 if (sizeof filename <
718 ((sizeof locale_home) + namesize + (sizeof lc_time)))
719 goto no_locale;
720 oldsun = 0;
721 (void) sprintf(filename, "%s/%s/%s", locale_home, name, lc_time);
722 fd = open(filename, O_RDONLY);
723 if (fd < 0) {
724 /*
725 ** Old Sun systems have a different naming and data convention.
726 */
727 oldsun = 1;
728 (void) sprintf(filename, "%s/%s/%s", locale_home,
729 lc_time, name);
730 fd = open(filename, O_RDONLY);
731 if (fd < 0)
732 goto no_locale;
733 }
734 if (fstat(fd, &st) != 0)
735 goto bad_locale;
736 if (st.st_size <= 0)
737 goto bad_locale;
738 bufsize = namesize + st.st_size;
739 locale_buf = NULL;
740 lbuf = (lbuf == NULL) ? malloc(bufsize) : realloc(lbuf, bufsize);
741 if (lbuf == NULL)
742 goto bad_locale;
743 (void) strcpy(lbuf, name);
744 p = lbuf + namesize;
745 plim = p + st.st_size;
746 if (read(fd, p, (size_t) st.st_size) != st.st_size)
747 goto bad_lbuf;
748 if (close(fd) != 0)
749 goto bad_lbuf;
750 /*
751 ** Parse the locale file into localebuf.
752 */
753 if (plim[-1] != '\n')
754 goto bad_lbuf;
755 for (ap = (const char **) &localebuf;
756 ap < (const char **) (&localebuf + 1);
757 ++ap) {
758 if (p == plim)
759 goto bad_lbuf;
760 *ap = p;
761 while (*p != '\n')
762 ++p;
763 *p++ = '\0';
764 }
765 if (oldsun) {
766 /*
767 ** SunOS 4 used an obsolescent format; see localdtconv(3).
768 ** c_fmt had the ``short format for dates and times together''
769 ** (SunOS 4 date, "%a %b %e %T %Z %Y" in the C locale);
770 ** date_fmt had the ``long format for dates''
771 ** (SunOS 4 strftime %C, "%A, %B %e, %Y" in the C locale).
772 ** Discard the latter in favor of the former.
773 */
774 localebuf.date_fmt = localebuf.c_fmt;
775 }
776 /*
777 ** Record the successful parse in the cache.
778 */
779 locale_buf = lbuf;
780
781 return &localebuf;
782
783 bad_lbuf:
784 free(lbuf);
785 bad_locale:
786 (void) close(fd);
787 no_locale:
788 localebuf = C_time_locale;
789 locale_buf = NULL;
790 return &localebuf;
791 }
792 #endif /* defined LOCALE_HOME */
793