1 /*	$OpenBSD: wcsftime.c,v 1.3 2014/05/06 15:49:45 tedu Exp $ */
2 #include "private.h"
3 
4 /*
5 ** Based on the UCB version with the ID appearing below.
6 ** This is ANSIish only when "multibyte character == plain character".
7 **
8 ** Copyright (c) 1989, 1993
9 **	The Regents of the University of California.  All rights reserved.
10 **
11 ** Redistribution and use in source and binary forms, with or without
12 ** modification, are permitted provided that the following conditions
13 ** are met:
14 ** 1. Redistributions of source code must retain the above copyright
15 **    notice, this list of conditions and the following disclaimer.
16 ** 2. Redistributions in binary form must reproduce the above copyright
17 **    notice, this list of conditions and the following disclaimer in the
18 **    documentation and/or other materials provided with the distribution.
19 ** 3. Neither the name of the University nor the names of its contributors
20 **    may be used to endorse or promote products derived from this software
21 **    without specific prior written permission.
22 **
23 ** THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 ** ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 ** OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 ** HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 ** SUCH DAMAGE.
34 */
35 
36 #include "tzfile.h"
37 #include "fcntl.h"
38 #include <locale.h>
39 #include <wchar.h>
40 
41 struct lc_time_T {
42 	const wchar_t *	mon[MONSPERYEAR];
43 	const wchar_t *	month[MONSPERYEAR];
44 	const wchar_t *	wday[DAYSPERWEEK];
45 	const wchar_t *	weekday[DAYSPERWEEK];
46 	const wchar_t *	X_fmt;
47 	const wchar_t *	x_fmt;
48 	const wchar_t *	c_fmt;
49 	const wchar_t *	am;
50 	const wchar_t *	pm;
51 	const wchar_t *	date_fmt;
52 };
53 
54 #define Locale	(&C_time_locale)
55 
56 static const struct lc_time_T	C_time_locale = {
57 	{
58 		L"Jan", L"Feb", L"Mar", L"Apr", L"May", L"Jun",
59 		L"Jul", L"Aug", L"Sep", L"Oct", L"Nov", L"Dec"
60 	}, {
61 		L"January", L"February", L"March", L"April", L"May", L"June",
62 		L"July", L"August", L"September", L"October", L"November",
63 		L"December"
64 	}, {
65 		L"Sun", L"Mon", L"Tue", L"Wed",
66 		L"Thu", L"Fri", L"Sat"
67 	}, {
68 		L"Sunday", L"Monday", L"Tuesday", L"Wednesday",
69 		L"Thursday", L"Friday", L"Saturday"
70 	},
71 
72 	/* X_fmt */
73 	L"%H:%M:%S",
74 
75 	/*
76 	** x_fmt
77 	** C99 requires this format.
78 	** Using just numbers (as here) makes Quakers happier;
79 	** it's also compatible with SVR4.
80 	*/
81 	L"%m/%d/%y",
82 
83 	/*
84 	** c_fmt
85 	** C99 requires this format.
86 	** Previously this code used "%D %X", but we now conform to C99.
87 	** Note that
88 	**	"%a %b %d %H:%M:%S %Y"
89 	** is used by Solaris 2.3.
90 	*/
91 	L"%a %b %e %T %Y",
92 
93 	/* am */
94 	L"AM",
95 
96 	/* pm */
97 	L"PM",
98 
99 	/* date_fmt */
100 	L"%a %b %e %H:%M:%S %Z %Y"
101 };
102 
103 #define UNKNOWN L"?"
104 static wchar_t *	_add(const wchar_t *, wchar_t *, const wchar_t *);
105 static wchar_t *	_sadd(const char *, wchar_t *, const wchar_t *);
106 static wchar_t *	_conv(int, const wchar_t *, wchar_t *, const wchar_t *);
107 static wchar_t *	_fmt(const wchar_t *, const struct tm *, wchar_t *, const wchar_t *,
108 			int *);
109 static wchar_t *	_yconv(int, int, int, int, wchar_t *, const wchar_t *);
110 
111 extern char *	tzname[];
112 
113 #define IN_NONE	0
114 #define IN_SOME	1
115 #define IN_THIS	2
116 #define IN_ALL	3
117 
118 size_t
wcsftime(wchar_t * __restrict s,size_t maxsize,const wchar_t * __restrict format,const struct tm * __restrict t)119 wcsftime(wchar_t *__restrict s, size_t maxsize,
120     const wchar_t *__restrict format, const struct tm *__restrict t)
121 {
122 	wchar_t *p;
123 	int	warn;
124 
125 	tzset();
126 	warn = IN_NONE;
127 	p = _fmt(((format == NULL) ? L"%c" : format), t, s, s + maxsize, &warn);
128 	if (p == s + maxsize) {
129 		if (maxsize > 0)
130 			s[maxsize - 1] = '\0';
131 		return 0;
132 	}
133 	*p = L'\0';
134 	return p - s;
135 }
136 
137 static wchar_t *
_fmt(const wchar_t * format,const struct tm * t,wchar_t * pt,const wchar_t * ptlim,int * warnp)138 _fmt(const wchar_t *format, const struct tm *t, wchar_t *pt,
139     const wchar_t *ptlim, int *warnp)
140 {
141 	for ( ; *format; ++format) {
142 		if (*format != L'%') {
143 			if (pt == ptlim)
144 				break;
145 			*pt++ = *format;
146 			continue;
147 		}
148 label:
149 		switch (*++format) {
150 		case '\0':
151 			--format;
152 			break;
153 		case 'A':
154 			pt = _add((t->tm_wday < 0 ||
155 				t->tm_wday >= DAYSPERWEEK) ?
156 				UNKNOWN : Locale->weekday[t->tm_wday],
157 				pt, ptlim);
158 			continue;
159 		case 'a':
160 			pt = _add((t->tm_wday < 0 ||
161 				t->tm_wday >= DAYSPERWEEK) ?
162 				UNKNOWN : Locale->wday[t->tm_wday],
163 				pt, ptlim);
164 			continue;
165 		case 'B':
166 			pt = _add((t->tm_mon < 0 ||
167 				t->tm_mon >= MONSPERYEAR) ?
168 				UNKNOWN : Locale->month[t->tm_mon],
169 				pt, ptlim);
170 			continue;
171 		case 'b':
172 		case 'h':
173 			pt = _add((t->tm_mon < 0 ||
174 				t->tm_mon >= MONSPERYEAR) ?
175 				UNKNOWN : Locale->mon[t->tm_mon],
176 				pt, ptlim);
177 			continue;
178 		case 'C':
179 			/*
180 			** %C used to do a...
181 			**	_fmt("%a %b %e %X %Y", t);
182 			** ...whereas now POSIX 1003.2 calls for
183 			** something completely different.
184 			** (ado, 1993-05-24)
185 			*/
186 			pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 0,
187 				pt, ptlim);
188 			continue;
189 		case 'c':
190 			{
191 			int warn2 = IN_SOME;
192 
193 			pt = _fmt(Locale->c_fmt, t, pt, ptlim, &warn2);
194 			if (warn2 == IN_ALL)
195 				warn2 = IN_THIS;
196 			if (warn2 > *warnp)
197 				*warnp = warn2;
198 			}
199 			continue;
200 		case 'D':
201 			pt = _fmt(L"%m/%d/%y", t, pt, ptlim, warnp);
202 			continue;
203 		case 'd':
204 			pt = _conv(t->tm_mday, L"%02d", pt, ptlim);
205 			continue;
206 		case 'E':
207 		case 'O':
208 			/*
209 			** C99 locale modifiers.
210 			** The sequences
211 			**	%Ec %EC %Ex %EX %Ey %EY
212 			**	%Od %oe %OH %OI %Om %OM
213 			**	%OS %Ou %OU %OV %Ow %OW %Oy
214 			** are supposed to provide alternate
215 			** representations.
216 			*/
217 			goto label;
218 		case 'e':
219 			pt = _conv(t->tm_mday, L"%2d", pt, ptlim);
220 			continue;
221 		case 'F':
222 			pt = _fmt(L"%Y-%m-%d", t, pt, ptlim, warnp);
223 			continue;
224 		case 'H':
225 			pt = _conv(t->tm_hour, L"%02d", pt, ptlim);
226 			continue;
227 		case 'I':
228 			pt = _conv((t->tm_hour % 12) ?
229 				(t->tm_hour % 12) : 12,
230 				L"%02d", pt, ptlim);
231 			continue;
232 		case 'j':
233 			pt = _conv(t->tm_yday + 1, L"%03d", pt, ptlim);
234 			continue;
235 		case 'k':
236 			/*
237 			** This used to be...
238 			**	_conv(t->tm_hour % 12 ?
239 			**		t->tm_hour % 12 : 12, 2, ' ');
240 			** ...and has been changed to the below to
241 			** match SunOS 4.1.1 and Arnold Robbins'
242 			** strftime version 3.0. That is, "%k" and
243 			** "%l" have been swapped.
244 			** (ado, 1993-05-24)
245 			*/
246 			pt = _conv(t->tm_hour, L"%2d", pt, ptlim);
247 			continue;
248 		case 'l':
249 			/*
250 			** This used to be...
251 			**	_conv(t->tm_hour, 2, ' ');
252 			** ...and has been changed to the below to
253 			** match SunOS 4.1.1 and Arnold Robbin's
254 			** strftime version 3.0. That is, "%k" and
255 			** "%l" have been swapped.
256 			** (ado, 1993-05-24)
257 			*/
258 			pt = _conv((t->tm_hour % 12) ?
259 				(t->tm_hour % 12) : 12,
260 				L"%2d", pt, ptlim);
261 			continue;
262 		case 'M':
263 			pt = _conv(t->tm_min, L"%02d", pt, ptlim);
264 			continue;
265 		case 'm':
266 			pt = _conv(t->tm_mon + 1, L"%02d", pt, ptlim);
267 			continue;
268 		case 'n':
269 			pt = _add(L"\n", pt, ptlim);
270 			continue;
271 		case 'p':
272 			pt = _add((t->tm_hour >= (HOURSPERDAY / 2)) ?
273 				Locale->pm :
274 				Locale->am,
275 				pt, ptlim);
276 			continue;
277 		case 'R':
278 			pt = _fmt(L"%H:%M", t, pt, ptlim, warnp);
279 			continue;
280 		case 'r':
281 			pt = _fmt(L"%I:%M:%S %p", t, pt, ptlim, warnp);
282 			continue;
283 		case 'S':
284 			pt = _conv(t->tm_sec, L"%02d", pt, ptlim);
285 			continue;
286 		case 's':
287 			{
288 				struct tm	tm;
289 				wchar_t		buf[INT_STRLEN_MAXIMUM(
290 							time_t) + 1];
291 				time_t		mkt;
292 
293 				tm = *t;
294 				mkt = mktime(&tm);
295 				if (TYPE_SIGNED(time_t))
296 					(void) swprintf(buf,
297 					    sizeof buf/sizeof buf[0],
298 					    L"%ld", (long) mkt);
299 				else
300 					(void) swprintf(buf,
301 					    sizeof buf/sizeof buf[0],
302 					    L"%lu", (unsigned long) mkt);
303 				pt = _add(buf, pt, ptlim);
304 			}
305 			continue;
306 		case 'T':
307 			pt = _fmt(L"%H:%M:%S", t, pt, ptlim, warnp);
308 			continue;
309 		case 't':
310 			pt = _add(L"\t", pt, ptlim);
311 			continue;
312 		case 'U':
313 			pt = _conv((t->tm_yday + DAYSPERWEEK -
314 				t->tm_wday) / DAYSPERWEEK,
315 				L"%02d", pt, ptlim);
316 			continue;
317 		case 'u':
318 			/*
319 			** From Arnold Robbins' strftime version 3.0:
320 			** "ISO 8601: Weekday as a decimal number
321 			** [1 (Monday) - 7]"
322 			** (ado, 1993-05-24)
323 			*/
324 			pt = _conv((t->tm_wday == 0) ?
325 				DAYSPERWEEK : t->tm_wday,
326 				L"%d", pt, ptlim);
327 			continue;
328 		case 'V':	/* ISO 8601 week number */
329 		case 'G':	/* ISO 8601 year (four digits) */
330 		case 'g':	/* ISO 8601 year (two digits) */
331 /*
332 ** From Arnold Robbins' strftime version 3.0: "the week number of the
333 ** year (the first Monday as the first day of week 1) as a decimal number
334 ** (01-53)."
335 ** (ado, 1993-05-24)
336 **
337 ** From "http://www.ft.uni-erlangen.de/~mskuhn/iso-time.html" by Markus Kuhn:
338 ** "Week 01 of a year is per definition the first week which has the
339 ** Thursday in this year, which is equivalent to the week which contains
340 ** the fourth day of January. In other words, the first week of a new year
341 ** is the week which has the majority of its days in the new year. Week 01
342 ** might also contain days from the previous year and the week before week
343 ** 01 of a year is the last week (52 or 53) of the previous year even if
344 ** it contains days from the new year. A week starts with Monday (day 1)
345 ** and ends with Sunday (day 7). For example, the first week of the year
346 ** 1997 lasts from 1996-12-30 to 1997-01-05..."
347 ** (ado, 1996-01-02)
348 */
349 			{
350 			int	year;
351 			int	base;
352 			int	yday;
353 			int	wday;
354 			int	w;
355 
356 			year = t->tm_year;
357 			base = TM_YEAR_BASE;
358 			yday = t->tm_yday;
359 			wday = t->tm_wday;
360 			for ( ; ; ) {
361 				int	len;
362 				int	bot;
363 				int	top;
364 
365 				len = isleap_sum(year, base) ?
366 					DAYSPERLYEAR :
367 					DAYSPERNYEAR;
368 				/*
369 				** What yday (-3 ... 3) does the ISO year
370 				** begin on?
371 				*/
372 				bot = ((yday + 11 - wday) % DAYSPERWEEK) - 3;
373 				/*
374 				** What yday does the NEXT ISO year begin on?
375 				*/
376 				top = bot - (len % DAYSPERWEEK);
377 				if (top < -3)
378 					top += DAYSPERWEEK;
379 				top += len;
380 				if (yday >= top) {
381 					++base;
382 					w = 1;
383 					break;
384 				}
385 				if (yday >= bot) {
386 					w = 1 + ((yday - bot) / DAYSPERWEEK);
387 					break;
388 				}
389 				--base;
390 				yday += isleap_sum(year, base) ?
391 					DAYSPERLYEAR :
392 					DAYSPERNYEAR;
393 			}
394 			if ((w == 52 && t->tm_mon == TM_JANUARY) ||
395 				(w == 1 && t->tm_mon == TM_DECEMBER))
396 					w = 53;
397 			if (*format == 'V')
398 				pt = _conv(w, L"%02d", pt, ptlim);
399 			else if (*format == 'g') {
400 				*warnp = IN_ALL;
401 				pt = _yconv(year, base, 0, 1, pt, ptlim);
402 			} else
403 				pt = _yconv(year, base, 1, 1, pt, ptlim);
404 			}
405 			continue;
406 		case 'v':
407 			/*
408 			** From Arnold Robbins' strftime version 3.0:
409 			** "date as dd-bbb-YYYY"
410 			** (ado, 1993-05-24)
411 			*/
412 			pt = _fmt(L"%e-%b-%Y", t, pt, ptlim, warnp);
413 			continue;
414 		case 'W':
415 			pt = _conv((t->tm_yday + DAYSPERWEEK -
416 				(t->tm_wday ?
417 				(t->tm_wday - 1) :
418 				(DAYSPERWEEK - 1))) / DAYSPERWEEK,
419 				L"%02d", pt, ptlim);
420 			continue;
421 		case 'w':
422 			pt = _conv(t->tm_wday, L"%d", pt, ptlim);
423 			continue;
424 		case 'X':
425 			pt = _fmt(Locale->X_fmt, t, pt, ptlim, warnp);
426 			continue;
427 		case 'x':
428 			{
429 			int	warn2 = IN_SOME;
430 
431 			pt = _fmt(Locale->x_fmt, t, pt, ptlim, &warn2);
432 			if (warn2 == IN_ALL)
433 				warn2 = IN_THIS;
434 			if (warn2 > *warnp)
435 				*warnp = warn2;
436 			}
437 			continue;
438 		case 'y':
439 			*warnp = IN_ALL;
440 			pt = _yconv(t->tm_year, TM_YEAR_BASE, 0, 1, pt, ptlim);
441 			continue;
442 		case 'Y':
443 			pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 1, pt, ptlim);
444 			continue;
445 		case 'Z':
446 			if (t->tm_zone != NULL)
447 				pt = _sadd(t->TM_ZONE, pt, ptlim);
448 			else
449 				if (t->tm_isdst >= 0)
450 					pt = _sadd(tzname[t->tm_isdst != 0],
451 					    pt, ptlim);
452 			/*
453 			** C99 says that %Z must be replaced by the
454 			** empty string if the time zone is not
455 			** determinable.
456 			*/
457 			continue;
458 		case 'z':
459 			{
460 			int		diff;
461 			wchar_t const *	sign;
462 
463 			if (t->tm_isdst < 0)
464 				continue;
465 			diff = t->tm_gmtoff;
466 			if (diff < 0) {
467 				sign = L"-";
468 				diff = -diff;
469 			} else
470 				sign = L"+";
471 			pt = _add(sign, pt, ptlim);
472 			diff /= SECSPERMIN;
473 			diff = (diff / MINSPERHOUR) * 100 +
474 				(diff % MINSPERHOUR);
475 			pt = _conv(diff, L"%04d", pt, ptlim);
476 			}
477 			continue;
478 		case '+':
479 			pt = _fmt(Locale->date_fmt, t, pt, ptlim, warnp);
480 			continue;
481 		case '%':
482 		/*
483 		** X311J/88-090 (4.12.3.5): if conversion wchar_t is
484 		** undefined, behavior is undefined. Print out the
485 		** character itself as printf(3) also does.
486 		*/
487 		default:
488 			if (pt != ptlim)
489 				*pt++ = *format;
490 			break;
491 		}
492 	}
493 	return pt;
494 }
495 
496 static wchar_t *
_conv(int n,const wchar_t * format,wchar_t * pt,const wchar_t * ptlim)497 _conv(int n, const wchar_t *format, wchar_t *pt, const wchar_t *ptlim)
498 {
499 	wchar_t	buf[INT_STRLEN_MAXIMUM(int) + 1];
500 
501 	(void) swprintf(buf, sizeof buf/sizeof buf[0], format, n);
502 	return _add(buf, pt, ptlim);
503 }
504 
505 static wchar_t *
_add(const wchar_t * str,wchar_t * pt,const wchar_t * ptlim)506 _add(const wchar_t *str, wchar_t *pt, const wchar_t *ptlim)
507 {
508 	while (pt < ptlim && (*pt = *str++) != L'\0')
509 		++pt;
510 	return pt;
511 }
512 
513 static wchar_t *
_sadd(const char * str,wchar_t * pt,const wchar_t * ptlim)514 _sadd(const char *str, wchar_t *pt, const wchar_t *ptlim)
515 {
516 	while (pt < ptlim && (*pt = btowc(*str++)) != L'\0')
517 		++pt;
518 	return pt;
519 }
520 /*
521 ** POSIX and the C Standard are unclear or inconsistent about
522 ** what %C and %y do if the year is negative or exceeds 9999.
523 ** Use the convention that %C concatenated with %y yields the
524 ** same output as %Y, and that %Y contains at least 4 bytes,
525 ** with more only if necessary.
526 */
527 
528 static wchar_t *
_yconv(int a,int b,int convert_top,int convert_yy,wchar_t * pt,const wchar_t * ptlim)529 _yconv(int a, int b, int convert_top, int convert_yy, wchar_t *pt,
530     const wchar_t *ptlim)
531 {
532 	register int	lead;
533 	register int	trail;
534 
535 #define DIVISOR	100
536 	trail = a % DIVISOR + b % DIVISOR;
537 	lead = a / DIVISOR + b / DIVISOR + trail / DIVISOR;
538 	trail %= DIVISOR;
539 	if (trail < 0 && lead > 0) {
540 		trail += DIVISOR;
541 		--lead;
542 	} else if (lead < 0 && trail > 0) {
543 		trail -= DIVISOR;
544 		++lead;
545 	}
546 	if (convert_top) {
547 		if (lead == 0 && trail < 0)
548 			pt = _add(L"-0", pt, ptlim);
549 		else	pt = _conv(lead, L"%02d", pt, ptlim);
550 	}
551 	if (convert_yy)
552 		pt = _conv(((trail < 0) ? -trail : trail), L"%02d", pt, ptlim);
553 	return pt;
554 }
555 
556