]> git.saurik.com Git - apple/libc.git/blob - stdtime/FreeBSD/strftime.c
projects / apple / libc.git / blob
? search:


565c6d1c8ef1dcb5dc1d34dd828c75a30cc76651
[apple/libc.git] / stdtime / FreeBSD / strftime.c
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 #ifndef lint
19 #ifndef NOID
20 static const char elsieid[] = "@(#)strftime.c 7.38";
21 /*
22 ** Based on the UCB version with the ID appearing below.
23 ** This is ANSIish only when "multibyte character == plain character".
24 */
25 #endif /* !defined NOID */
26 #endif /* !defined lint */
27
28 #include "namespace.h"
29 #include "private.h"
30
31 #if defined(LIBC_SCCS) && !defined(lint)
32 static const char sccsid[] = "@(#)strftime.c 5.4 (Berkeley) 3/14/89";
33 #endif /* LIBC_SCCS and not lint */
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD: src/lib/libc/stdtime/strftime.c,v 1.38 2002/09/06 11:24:03 tjr Exp $");
36
37 #include "tzfile.h"
38 #include <fcntl.h>
39 #include <sys/stat.h>
40 #include "un-namespace.h"
41 #include "timelocal.h"
42
43 static char * _add(const char *, char *, const char *);
44 static char * _conv(int, const char *, char *, const char *);
45 static char * _fmt(const char *, const struct tm *, char *, const char *);
46
47 size_t strftime(char * __restrict, size_t, const char * __restrict,
48 const struct tm * __restrict);
49
50 extern char * tzname[];
51
52 size_t
53 strftime(char * __restrict s, size_t maxsize, const char * __restrict format,
54 const struct tm * __restrict t)
55 {
56 char *p;
57
58 tzset();
59 p = _fmt(((format == NULL) ? "%c" : format), t, s, s + maxsize);
60 if (p == s + maxsize)
61 return 0;
62 *p = '\0';
63 return p - s;
64 }
65
66 static char *
67 _fmt(format, t, pt, ptlim)
68 const char *format;
69 const struct tm *const t;
70 char *pt;
71 const char *const ptlim;
72 {
73 int Ealternative, Oalternative;
74 struct lc_time_T *tptr = __get_current_time_locale();
75
76 for ( ; *format; ++format) {
77 if (*format == '%') {
78 Ealternative = 0;
79 Oalternative = 0;
80 label:
81 switch (*++format) {
82 case '\0':
83 --format;
84 break;
85 case 'A':
86 pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ?
87 "?" : tptr->weekday[t->tm_wday],
88 pt, ptlim);
89 continue;
90 case 'a':
91 pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ?
92 "?" : tptr->wday[t->tm_wday],
93 pt, ptlim);
94 continue;
95 case 'B':
96 pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ?
97 "?" : (Oalternative ? tptr->alt_month :
98 tptr->month)[t->tm_mon],
99 pt, ptlim);
100 continue;
101 case 'b':
102 case 'h':
103 pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ?
104 "?" : tptr->mon[t->tm_mon],
105 pt, ptlim);
106 continue;
107 case 'C':
108 /*
109 ** %C used to do a...
110 ** _fmt("%a %b %e %X %Y", t);
111 ** ...whereas now POSIX 1003.2 calls for
112 ** something completely different.
113 ** (ado, 5/24/93)
114 */
115 pt = _conv((t->tm_year + TM_YEAR_BASE) / 100,
116 "%02d", pt, ptlim);
117 continue;
118 case 'c':
119 pt = _fmt(tptr->c_fmt, t, pt, ptlim);
120 continue;
121 case 'D':
122 pt = _fmt("%m/%d/%y", t, pt, ptlim);
123 continue;
124 case 'd':
125 pt = _conv(t->tm_mday, "%02d", pt, ptlim);
126 continue;
127 case 'E':
128 if (Ealternative || Oalternative)
129 break;
130 Ealternative++;
131 goto label;
132 case 'O':
133 /*
134 ** POSIX locale extensions, a la
135 ** Arnold Robbins' strftime version 3.0.
136 ** The sequences
137 ** %Ec %EC %Ex %EX %Ey %EY
138 ** %Od %oe %OH %OI %Om %OM
139 ** %OS %Ou %OU %OV %Ow %OW %Oy
140 ** are supposed to provide alternate
141 ** representations.
142 ** (ado, 5/24/93)
143 **
144 ** FreeBSD extensions
145 ** %OB %Ef %EF
146 */
147 if (Ealternative || Oalternative)
148 break;
149 Oalternative++;
150 goto label;
151 case 'e':
152 pt = _conv(t->tm_mday, "%2d", pt, ptlim);
153 continue;
154 case 'F':
155 pt = _fmt("%Y-%m-%d", t, pt, ptlim);
156 continue;
157 case 'H':
158 pt = _conv(t->tm_hour, "%02d", pt, ptlim);
159 continue;
160 case 'I':
161 pt = _conv((t->tm_hour % 12) ?
162 (t->tm_hour % 12) : 12,
163 "%02d", pt, ptlim);
164 continue;
165 case 'j':
166 pt = _conv(t->tm_yday + 1, "%03d", pt, ptlim);
167 continue;
168 case 'k':
169 /*
170 ** This used to be...
171 ** _conv(t->tm_hour % 12 ?
172 ** t->tm_hour % 12 : 12, 2, ' ');
173 ** ...and has been changed to the below to
174 ** match SunOS 4.1.1 and Arnold Robbins'
175 ** strftime version 3.0. That is, "%k" and
176 ** "%l" have been swapped.
177 ** (ado, 5/24/93)
178 */
179 pt = _conv(t->tm_hour, "%2d", pt, ptlim);
180 continue;
181 #ifdef KITCHEN_SINK
182 case 'K':
183 /*
184 ** After all this time, still unclaimed!
185 */
186 pt = _add("kitchen sink", pt, ptlim);
187 continue;
188 #endif /* defined KITCHEN_SINK */
189 case 'l':
190 /*
191 ** This used to be...
192 ** _conv(t->tm_hour, 2, ' ');
193 ** ...and has been changed to the below to
194 ** match SunOS 4.1.1 and Arnold Robbin's
195 ** strftime version 3.0. That is, "%k" and
196 ** "%l" have been swapped.
197 ** (ado, 5/24/93)
198 */
199 pt = _conv((t->tm_hour % 12) ?
200 (t->tm_hour % 12) : 12,
201 "%2d", pt, ptlim);
202 continue;
203 case 'M':
204 pt = _conv(t->tm_min, "%02d", pt, ptlim);
205 continue;
206 case 'm':
207 pt = _conv(t->tm_mon + 1, "%02d", pt, ptlim);
208 continue;
209 case 'n':
210 pt = _add("\n", pt, ptlim);
211 continue;
212 case 'p':
213 pt = _add((t->tm_hour >= 12) ?
214 tptr->pm :
215 tptr->am,
216 pt, ptlim);
217 continue;
218 case 'R':
219 pt = _fmt("%H:%M", t, pt, ptlim);
220 continue;
221 case 'r':
222 pt = _fmt(tptr->ampm_fmt, t, pt, ptlim);
223 continue;
224 case 'S':
225 pt = _conv(t->tm_sec, "%02d", pt, ptlim);
226 continue;
227 case 's':
228 {
229 struct tm tm;
230 char buf[INT_STRLEN_MAXIMUM(
231 time_t) + 1];
232 time_t mkt;
233
234 tm = *t;
235 mkt = mktime(&tm);
236 if (TYPE_SIGNED(time_t))
237 (void) sprintf(buf, "%ld",
238 (long) mkt);
239 else (void) sprintf(buf, "%lu",
240 (unsigned long) mkt);
241 pt = _add(buf, pt, ptlim);
242 }
243 continue;
244 case 'T':
245 pt = _fmt("%H:%M:%S", t, pt, ptlim);
246 continue;
247 case 't':
248 pt = _add("\t", pt, ptlim);
249 continue;
250 case 'U':
251 pt = _conv((t->tm_yday + 7 - t->tm_wday) / 7,
252 "%02d", pt, ptlim);
253 continue;
254 case 'u':
255 /*
256 ** From Arnold Robbins' strftime version 3.0:
257 ** "ISO 8601: Weekday as a decimal number
258 ** [1 (Monday) - 7]"
259 ** (ado, 5/24/93)
260 */
261 pt = _conv((t->tm_wday == 0) ? 7 : t->tm_wday,
262 "%d", pt, ptlim);
263 continue;
264 case 'V': /* ISO 8601 week number */
265 case 'G': /* ISO 8601 year (four digits) */
266 case 'g': /* ISO 8601 year (two digits) */
267 /*
268 ** From Arnold Robbins' strftime version 3.0: "the week number of the
269 ** year (the first Monday as the first day of week 1) as a decimal number
270 ** (01-53)."
271 ** (ado, 1993-05-24)
272 **
273 ** From "http://www.ft.uni-erlangen.de/~mskuhn/iso-time.html" by Markus Kuhn:
274 ** "Week 01 of a year is per definition the first week which has the
275 ** Thursday in this year, which is equivalent to the week which contains
276 ** the fourth day of January. In other words, the first week of a new year
277 ** is the week which has the majority of its days in the new year. Week 01
278 ** might also contain days from the previous year and the week before week
279 ** 01 of a year is the last week (52 or 53) of the previous year even if
280 ** it contains days from the new year. A week starts with Monday (day 1)
281 ** and ends with Sunday (day 7). For example, the first week of the year
282 ** 1997 lasts from 1996-12-30 to 1997-01-05..."
283 ** (ado, 1996-01-02)
284 */
285 {
286 int year;
287 int yday;
288 int wday;
289 int w;
290
291 year = t->tm_year + TM_YEAR_BASE;
292 yday = t->tm_yday;
293 wday = t->tm_wday;
294 for ( ; ; ) {
295 int len;
296 int bot;
297 int top;
298
299 len = isleap(year) ?
300 DAYSPERLYEAR :
301 DAYSPERNYEAR;
302 /*
303 ** What yday (-3 ... 3) does
304 ** the ISO year begin on?
305 */
306 bot = ((yday + 11 - wday) %
307 DAYSPERWEEK) - 3;
308 /*
309 ** What yday does the NEXT
310 ** ISO year begin on?
311 */
312 top = bot -
313 (len % DAYSPERWEEK);
314 if (top < -3)
315 top += DAYSPERWEEK;
316 top += len;
317 if (yday >= top) {
318 ++year;
319 w = 1;
320 break;
321 }
322 if (yday >= bot) {
323 w = 1 + ((yday - bot) /
324 DAYSPERWEEK);
325 break;
326 }
327 --year;
328 yday += isleap(year) ?
329 DAYSPERLYEAR :
330 DAYSPERNYEAR;
331 }
332 #ifdef XPG4_1994_04_09
333 if ((w == 52
334 && t->tm_mon == TM_JANUARY)
335 || (w == 1
336 && t->tm_mon == TM_DECEMBER))
337 w = 53;
338 #endif /* defined XPG4_1994_04_09 */
339 if (*format == 'V')
340 pt = _conv(w, "%02d",
341 pt, ptlim);
342 else if (*format == 'g') {
343 pt = _conv(year % 100, "%02d",
344 pt, ptlim);
345 } else pt = _conv(year, "%04d",
346 pt, ptlim);
347 }
348 continue;
349 case 'v':
350 /*
351 ** From Arnold Robbins' strftime version 3.0:
352 ** "date as dd-bbb-YYYY"
353 ** (ado, 5/24/93)
354 */
355 pt = _fmt("%e-%b-%Y", t, pt, ptlim);
356 continue;
357 case 'W':
358 pt = _conv((t->tm_yday + 7 -
359 (t->tm_wday ?
360 (t->tm_wday - 1) : 6)) / 7,
361 "%02d", pt, ptlim);
362 continue;
363 case 'w':
364 pt = _conv(t->tm_wday, "%d", pt, ptlim);
365 continue;
366 case 'X':
367 pt = _fmt(tptr->X_fmt, t, pt, ptlim);
368 continue;
369 case 'x':
370 pt = _fmt(tptr->x_fmt, t, pt, ptlim);
371 continue;
372 case 'y':
373 pt = _conv((t->tm_year + TM_YEAR_BASE) % 100,
374 "%02d", pt, ptlim);
375 continue;
376 case 'Y':
377 pt = _conv(t->tm_year + TM_YEAR_BASE, "%04d",
378 pt, ptlim);
379 continue;
380 case 'Z':
381 if (t->tm_zone != NULL)
382 pt = _add(t->tm_zone, pt, ptlim);
383 else
384 if (t->tm_isdst == 0 || t->tm_isdst == 1) {
385 pt = _add(tzname[t->tm_isdst],
386 pt, ptlim);
387 } else pt = _add("?", pt, ptlim);
388 continue;
389 case 'z':
390 {
391 long absoff;
392 if (t->tm_gmtoff >= 0) {
393 absoff = t->tm_gmtoff;
394 pt = _add("+", pt, ptlim);
395 } else {
396 absoff = -t->tm_gmtoff;
397 pt = _add("-", pt, ptlim);
398 }
399 pt = _conv(absoff / 3600, "%02d",
400 pt, ptlim);
401 pt = _conv((absoff % 3600) / 60, "%02d",
402 pt, ptlim);
403 };
404 continue;
405 case '+':
406 pt = _fmt(tptr->date_fmt, t, pt, ptlim);
407 continue;
408 case '%':
409 /*
410 * X311J/88-090 (4.12.3.5): if conversion char is
411 * undefined, behavior is undefined. Print out the
412 * character itself as printf(3) also does.
413 */
414 default:
415 break;
416 }
417 }
418 if (pt == ptlim)
419 break;
420 *pt++ = *format;
421 }
422 return pt;
423 }
424
425 static char *
426 _conv(n, format, pt, ptlim)
427 const int n;
428 const char *const format;
429 char *const pt;
430 const char *const ptlim;
431 {
432 char buf[INT_STRLEN_MAXIMUM(int) + 1];
433
434 (void) sprintf(buf, format, n);
435 return _add(buf, pt, ptlim);
436 }
437
438 static char *
439 _add(str, pt, ptlim)
440 const char *str;
441 char *pt;
442 const char *const ptlim;
443 {
444 while (pt < ptlim && (*pt = *str++) != '\0')
445 ++pt;
446 return pt;
447 }
mirror of libc