2 * Copyright (c) 1989 The Regents of the University of California.
5 * Copyright (c) 2011 The FreeBSD Foundation
7 * Portions of this software were developed by David Chisnall
8 * under sponsorship from the FreeBSD Foundation.
10 * Redistribution and use in source and binary forms are permitted
11 * provided that the above copyright notice and this paragraph are
12 * duplicated in all such forms and that any documentation,
13 * advertising materials, and other materials related to such
14 * distribution and use acknowledge that the software was developed
15 * by the University of California, Berkeley. The name of the
16 * University may not be used to endorse or promote products derived
17 * from this software without specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22 * @(#)strftime.c 5.4 (Berkeley) 3/14/89
23 * $FreeBSD: head/lib/libc/stdtime/strftime.c 237211 2012-06-17 21:40:13Z jilles $
27 #include "namespace.h"
33 #include "un-namespace.h"
34 #include "timelocal.h"
36 static char * _add(const char *, char *, const char *);
37 static char * _conv(int, const char *, char *, const char *);
38 static char * _fmt(const char *, const struct tm *, char *, const char *,
40 static char * _yconv(int, int, int, int, char *, const char *);
42 extern char * tzname[];
44 #ifndef YEAR_2000_NAME
45 #define YEAR_2000_NAME "CHECK_STRFTIME_FORMATS_FOR_TWO_DIGIT_YEARS"
46 #endif /* !defined YEAR_2000_NAME */
58 static const char fmt_padding[][4][5] = {
59 /* DEFAULT, LESS, SPACE, ZERO */
60 #define PAD_FMT_MONTHDAY 0
62 #define PAD_FMT_CENTURY 0
63 #define PAD_FMT_SHORTYEAR 0
64 #define PAD_FMT_MONTH 0
65 #define PAD_FMT_WEEKOFYEAR 0
66 #define PAD_FMT_DAYOFMONTH 0
67 { "%02d", "%d", "%2d", "%02d" },
68 #define PAD_FMT_SDAYOFMONTH 1
69 #define PAD_FMT_SHMS 1
70 { "%2d", "%d", "%2d", "%02d" },
71 #define PAD_FMT_DAYOFYEAR 2
72 { "%03d", "%d", "%3d", "%03d" },
73 #define PAD_FMT_YEAR 3
74 { "%04d", "%d", "%4d", "%04d" }
78 strftime_l(char * __restrict s, size_t maxsize, const char * __restrict format,
79 const struct tm * __restrict t, locale_t loc)
87 p = _fmt(((format == NULL) ? "%c" : format), t, s, s + maxsize, &warn, loc);
88 #ifndef NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU
89 if (warn != IN_NONE && getenv(YEAR_2000_NAME) != NULL) {
90 fprintf_l(stderr, loc, "\n");
92 fprintf_l(stderr, loc, "NULL strftime format ");
93 else fprintf_l(stderr, loc, "strftime format \"%s\" ",
95 fprintf_l(stderr, loc, "yields only two digits of years in ");
97 fprintf_l(stderr, loc, "some locales");
98 else if (warn == IN_THIS)
99 fprintf_l(stderr, loc, "the current locale");
100 else fprintf_l(stderr, loc, "all locales");
101 fprintf_l(stderr, loc, "\n");
103 #endif /* !defined NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU */
104 if (p == s + maxsize)
111 strftime(char * __restrict s, size_t maxsize, const char * __restrict format,
112 const struct tm * __restrict t)
114 return strftime_l(s, maxsize, format, t, __get_locale());
118 _fmt(const char *format, const struct tm * const t, char *pt,
119 const char * const ptlim, int *warnp, locale_t loc)
121 int Ealternative, Oalternative, PadIndex;
122 struct lc_time_T *tptr = __get_current_time_locale(loc);
124 for ( ; *format; ++format) {
125 if (*format == '%') {
128 PadIndex = PAD_DEFAULT;
135 pt = _add((t->tm_wday < 0 ||
136 t->tm_wday >= DAYSPERWEEK) ?
137 "?" : tptr->weekday[t->tm_wday],
141 pt = _add((t->tm_wday < 0 ||
142 t->tm_wday >= DAYSPERWEEK) ?
143 "?" : tptr->wday[t->tm_wday],
147 pt = _add((t->tm_mon < 0 ||
148 t->tm_mon >= MONSPERYEAR) ?
149 "?" : (Oalternative ? tptr->alt_month :
150 tptr->month)[t->tm_mon],
155 pt = _add((t->tm_mon < 0 ||
156 t->tm_mon >= MONSPERYEAR) ?
157 "?" : tptr->mon[t->tm_mon],
163 * _fmt("%a %b %e %X %Y", t);
164 * ...whereas now POSIX 1003.2 calls for
165 * something completely different.
168 pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 0,
175 pt = _fmt(tptr->c_fmt, t, pt, ptlim, &warn2, loc);
183 pt = _fmt("%m/%d/%y", t, pt, ptlim, warnp, loc);
186 pt = _conv(t->tm_mday, fmt_padding[PAD_FMT_DAYOFMONTH][PadIndex],
190 if (Ealternative || Oalternative)
196 * C99 locale modifiers.
198 * %Ec %EC %Ex %EX %Ey %EY
199 * %Od %oe %OH %OI %Om %OM
200 * %OS %Ou %OU %OV %Ow %OW %Oy
201 * are supposed to provide alternate
207 if (Ealternative || Oalternative)
212 pt = _conv(t->tm_mday,
213 fmt_padding[PAD_FMT_SDAYOFMONTH][PadIndex], pt, ptlim);
216 pt = _fmt("%Y-%m-%d", t, pt, ptlim, warnp, loc);
219 pt = _conv(t->tm_hour, fmt_padding[PAD_FMT_HMS][PadIndex],
223 pt = _conv((t->tm_hour % 12) ?
224 (t->tm_hour % 12) : 12,
225 fmt_padding[PAD_FMT_HMS][PadIndex], pt, ptlim);
228 pt = _conv(t->tm_yday + 1,
229 fmt_padding[PAD_FMT_DAYOFYEAR][PadIndex], pt, ptlim);
234 * _conv(t->tm_hour % 12 ?
235 * t->tm_hour % 12 : 12, 2, ' ');
236 * ...and has been changed to the below to
237 * match SunOS 4.1.1 and Arnold Robbins'
238 * strftime version 3.0. That is, "%k" and
239 * "%l" have been swapped.
242 pt = _conv(t->tm_hour, fmt_padding[PAD_FMT_SHMS][PadIndex],
248 * After all this time, still unclaimed!
250 pt = _add("kitchen sink", pt, ptlim);
252 #endif /* defined KITCHEN_SINK */
256 * _conv(t->tm_hour, 2, ' ');
257 * ...and has been changed to the below to
258 * match SunOS 4.1.1 and Arnold Robbin's
259 * strftime version 3.0. That is, "%k" and
260 * "%l" have been swapped.
263 pt = _conv((t->tm_hour % 12) ?
264 (t->tm_hour % 12) : 12,
265 fmt_padding[PAD_FMT_SHMS][PadIndex], pt, ptlim);
268 pt = _conv(t->tm_min, fmt_padding[PAD_FMT_HMS][PadIndex],
272 pt = _conv(t->tm_mon + 1,
273 fmt_padding[PAD_FMT_MONTH][PadIndex], pt, ptlim);
276 pt = _add("\n", pt, ptlim);
279 pt = _add((t->tm_hour >= (HOURSPERDAY / 2)) ?
285 pt = _fmt("%H:%M", t, pt, ptlim, warnp, loc);
288 pt = _fmt(tptr->ampm_fmt, t, pt, ptlim,
292 pt = _conv(t->tm_sec, fmt_padding[PAD_FMT_HMS][PadIndex],
298 char buf[INT_STRLEN_MAXIMUM(
304 if (TYPE_SIGNED(time_t))
305 snprintf(buf, sizeof(buf),
308 else snprintf(buf, sizeof(buf),
311 pt = _add(buf, pt, ptlim);
315 pt = _fmt("%H:%M:%S", t, pt, ptlim, warnp, loc);
318 pt = _add("\t", pt, ptlim);
321 pt = _conv((t->tm_yday + DAYSPERWEEK -
322 t->tm_wday) / DAYSPERWEEK,
323 fmt_padding[PAD_FMT_WEEKOFYEAR][PadIndex], pt, ptlim);
327 * From Arnold Robbins' strftime version 3.0:
328 * "ISO 8601: Weekday as a decimal number
332 pt = _conv((t->tm_wday == 0) ?
333 DAYSPERWEEK : t->tm_wday,
336 case 'V': /* ISO 8601 week number */
337 case 'G': /* ISO 8601 year (four digits) */
338 case 'g': /* ISO 8601 year (two digits) */
340 * From Arnold Robbins' strftime version 3.0: "the week number of the
341 * year (the first Monday as the first day of week 1) as a decimal number
345 * From "http://www.ft.uni-erlangen.de/~mskuhn/iso-time.html" by Markus Kuhn:
346 * "Week 01 of a year is per definition the first week which has the
347 * Thursday in this year, which is equivalent to the week which contains
348 * the fourth day of January. In other words, the first week of a new year
349 * is the week which has the majority of its days in the new year. Week 01
350 * might also contain days from the previous year and the week before week
351 * 01 of a year is the last week (52 or 53) of the previous year even if
352 * it contains days from the new year. A week starts with Monday (day 1)
353 * and ends with Sunday (day 7). For example, the first week of the year
354 * 1997 lasts from 1996-12-30 to 1997-01-05..."
373 len = isleap_sum(year, base) ?
377 * What yday (-3 ... 3) does
378 * the ISO year begin on?
380 bot = ((yday + 11 - wday) %
383 * What yday does the NEXT
397 w = 1 + ((yday - bot) /
402 yday += isleap_sum(year, base) ?
406 #ifdef XPG4_1994_04_09
408 t->tm_mon == TM_JANUARY) ||
410 t->tm_mon == TM_DECEMBER))
412 #endif /* defined XPG4_1994_04_09 */
414 pt = _conv(w, fmt_padding[PAD_FMT_WEEKOFYEAR][PadIndex],
416 else if (*format == 'g') {
418 pt = _yconv(year, base, 0, 1,
420 } else pt = _yconv(year, base, 1, 1,
426 * From Arnold Robbins' strftime version 3.0:
427 * "date as dd-bbb-YYYY"
430 pt = _fmt("%e-%b-%Y", t, pt, ptlim, warnp, loc);
433 pt = _conv((t->tm_yday + DAYSPERWEEK -
436 (DAYSPERWEEK - 1))) / DAYSPERWEEK,
437 fmt_padding[PAD_FMT_WEEKOFYEAR][PadIndex], pt, ptlim);
440 pt = _conv(t->tm_wday, "%d", pt, ptlim);
443 pt = _fmt(tptr->X_fmt, t, pt, ptlim, warnp, loc);
449 pt = _fmt(tptr->x_fmt, t, pt, ptlim, &warn2, loc);
458 pt = _yconv(t->tm_year, TM_YEAR_BASE, 0, 1,
462 pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 1,
466 if (t->TM_ZONE != NULL)
467 pt = _add(t->TM_ZONE, pt, ptlim);
469 if (t->tm_isdst >= 0)
470 pt = _add(tzname[t->tm_isdst != 0],
473 * C99 says that %Z must be replaced by the
474 * empty string if the time zone is not
491 pt = _add(sign, pt, ptlim);
493 diff = (diff / MINSPERHOUR) * 100 +
494 (diff % MINSPERHOUR);
496 fmt_padding[PAD_FMT_YEAR][PadIndex], pt, ptlim);
500 pt = _fmt(tptr->date_fmt, t, pt, ptlim,
504 if (PadIndex != PAD_DEFAULT)
509 if (PadIndex != PAD_DEFAULT)
511 PadIndex = PAD_SPACE;
514 if (PadIndex != PAD_DEFAULT)
520 * X311J/88-090 (4.12.3.5): if conversion char is
521 * undefined, behavior is undefined. Print out the
522 * character itself as printf(3) also does.
536 _conv(const int n, const char * const format, char * const pt,
537 const char * const ptlim)
539 char buf[INT_STRLEN_MAXIMUM(int) + 1];
541 snprintf(buf, sizeof(buf), format, n);
542 return _add(buf, pt, ptlim);
546 _add(const char *str, char *pt, const char * const ptlim)
548 while (pt < ptlim && (*pt = *str++) != '\0')
554 * POSIX and the C Standard are unclear or inconsistent about
555 * what %C and %y do if the year is negative or exceeds 9999.
556 * Use the convention that %C concatenated with %y yields the
557 * same output as %Y, and that %Y contains at least 4 bytes,
558 * with more only if necessary.
562 _yconv(const int a, const int b, const int convert_top, const int convert_yy,
563 char *pt, const char * const ptlim)
569 trail = a % DIVISOR + b % DIVISOR;
570 lead = a / DIVISOR + b / DIVISOR + trail / DIVISOR;
572 if (trail < 0 && lead > 0) {
575 } else if (lead < 0 && trail > 0) {
580 if (lead == 0 && trail < 0)
581 pt = _add("-0", pt, ptlim);
582 else pt = _conv(lead, "%02d", pt, ptlim);
585 pt = _conv(((trail < 0) ? -trail : trail), "%02d", pt, ptlim);