bc42155199
* Replay 2010[acflm] which had been merged but not recorded. * Merge 2010n. * Reorganize (unsplit) the code to match the upstream layout. * Merge 2022[cdefg]. MFC after: 1 week Sponsored by: Klara, Inc.
644 lines
16 KiB
C
644 lines
16 KiB
C
/*
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* Copyright (c) 1989 The Regents of the University of California.
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* All rights reserved.
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*
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* Copyright (c) 2011 The FreeBSD Foundation
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*
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* Portions of this software were developed by David Chisnall
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* under sponsorship from the FreeBSD Foundation.
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*
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* Redistribution and use in source and binary forms are permitted
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* provided that the above copyright notice and this paragraph are
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* duplicated in all such forms and that any documentation,
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* advertising materials, and other materials related to such
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* distribution and use acknowledge that the software was developed
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* by the University of California, Berkeley. The name of the
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* University may not be used to endorse or promote products derived
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* from this software without specific prior written permission.
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* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
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* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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*/
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#ifndef lint
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#ifndef NOID
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static const char elsieid[] = "@(#)strftime.3 8.3";
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/*
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* Based on the UCB version with the ID appearing below.
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* This is ANSIish only when "multibyte character == plain character".
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*/
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#endif /* !defined NOID */
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#endif /* !defined lint */
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#include "namespace.h"
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#include "private.h"
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#if defined(LIBC_SCCS) && !defined(lint)
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static const char sccsid[] = "@(#)strftime.c 5.4 (Berkeley) 3/14/89";
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#endif /* LIBC_SCCS and not lint */
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include "tzfile.h"
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#include <fcntl.h>
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#include <sys/stat.h>
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#include <stdio.h>
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#include "un-namespace.h"
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#include "timelocal.h"
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static char * _add(const char *, char *, const char *);
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static char * _conv(int, const char *, char *, const char *, locale_t);
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static char * _fmt(const char *, const struct tm *, char *, const char *,
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int *, locale_t);
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static char * _yconv(int, int, int, int, char *, const char *, locale_t);
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extern char * tzname[];
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#ifndef YEAR_2000_NAME
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#define YEAR_2000_NAME "CHECK_STRFTIME_FORMATS_FOR_TWO_DIGIT_YEARS"
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#endif /* !defined YEAR_2000_NAME */
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#define IN_NONE 0
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#define IN_SOME 1
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#define IN_THIS 2
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#define IN_ALL 3
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#define PAD_DEFAULT 0
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#define PAD_LESS 1
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#define PAD_SPACE 2
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#define PAD_ZERO 3
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static const char fmt_padding[][4][5] = {
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/* DEFAULT, LESS, SPACE, ZERO */
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#define PAD_FMT_MONTHDAY 0
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#define PAD_FMT_HMS 0
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#define PAD_FMT_CENTURY 0
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#define PAD_FMT_SHORTYEAR 0
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#define PAD_FMT_MONTH 0
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#define PAD_FMT_WEEKOFYEAR 0
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#define PAD_FMT_DAYOFMONTH 0
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{ "%02d", "%d", "%2d", "%02d" },
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#define PAD_FMT_SDAYOFMONTH 1
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#define PAD_FMT_SHMS 1
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{ "%2d", "%d", "%2d", "%02d" },
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#define PAD_FMT_DAYOFYEAR 2
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{ "%03d", "%d", "%3d", "%03d" },
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#define PAD_FMT_YEAR 3
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{ "%04d", "%d", "%4d", "%04d" }
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};
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size_t
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strftime_l(char * __restrict s, size_t maxsize, const char * __restrict format,
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const struct tm * __restrict t, locale_t loc)
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{
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char * p;
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int warn;
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FIX_LOCALE(loc);
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tzset();
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warn = IN_NONE;
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p = _fmt(((format == NULL) ? "%c" : format), t, s, s + maxsize, &warn, loc);
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#ifndef NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU
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if (warn != IN_NONE && getenv(YEAR_2000_NAME) != NULL) {
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(void) fprintf_l(stderr, loc, "\n");
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if (format == NULL)
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(void) fputs("NULL strftime format ", stderr);
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else (void) fprintf_l(stderr, loc, "strftime format \"%s\" ",
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format);
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(void) fputs("yields only two digits of years in ", stderr);
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if (warn == IN_SOME)
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(void) fputs("some locales", stderr);
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else if (warn == IN_THIS)
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(void) fputs("the current locale", stderr);
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else (void) fputs("all locales", stderr);
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(void) fputs("\n", stderr);
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}
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#endif /* !defined NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU */
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if (p == s + maxsize)
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return (0);
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*p = '\0';
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return p - s;
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}
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size_t
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strftime(char * __restrict s, size_t maxsize, const char * __restrict format,
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const struct tm * __restrict t)
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{
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return strftime_l(s, maxsize, format, t, __get_locale());
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}
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static char *
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_fmt(const char *format, const struct tm * const t, char *pt,
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const char * const ptlim, int *warnp, locale_t loc)
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{
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int Ealternative, Oalternative, PadIndex;
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struct lc_time_T *tptr = __get_current_time_locale(loc);
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for ( ; *format; ++format) {
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if (*format == '%') {
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Ealternative = 0;
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Oalternative = 0;
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PadIndex = PAD_DEFAULT;
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label:
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switch (*++format) {
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case '\0':
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--format;
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break;
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case 'A':
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pt = _add((t->tm_wday < 0 ||
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t->tm_wday >= DAYSPERWEEK) ?
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"?" : tptr->weekday[t->tm_wday],
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pt, ptlim);
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continue;
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case 'a':
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pt = _add((t->tm_wday < 0 ||
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t->tm_wday >= DAYSPERWEEK) ?
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"?" : tptr->wday[t->tm_wday],
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pt, ptlim);
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continue;
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case 'B':
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pt = _add((t->tm_mon < 0 ||
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t->tm_mon >= MONSPERYEAR) ?
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"?" : (Oalternative ? tptr->alt_month :
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tptr->month)[t->tm_mon],
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pt, ptlim);
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continue;
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case 'b':
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case 'h':
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pt = _add((t->tm_mon < 0 ||
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t->tm_mon >= MONSPERYEAR) ?
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"?" : tptr->mon[t->tm_mon],
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pt, ptlim);
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continue;
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case 'C':
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/*
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* %C used to do a...
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* _fmt("%a %b %e %X %Y", t);
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* ...whereas now POSIX 1003.2 calls for
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* something completely different.
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* (ado, 1993-05-24)
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*/
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pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 0,
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pt, ptlim, loc);
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continue;
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case 'c':
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{
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int warn2 = IN_SOME;
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pt = _fmt(tptr->c_fmt, t, pt, ptlim, &warn2, loc);
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if (warn2 == IN_ALL)
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warn2 = IN_THIS;
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if (warn2 > *warnp)
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*warnp = warn2;
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}
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continue;
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case 'D':
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pt = _fmt("%m/%d/%y", t, pt, ptlim, warnp, loc);
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continue;
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case 'd':
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pt = _conv(t->tm_mday,
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fmt_padding[PAD_FMT_DAYOFMONTH][PadIndex],
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pt, ptlim, loc);
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continue;
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case 'E':
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if (Ealternative || Oalternative)
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break;
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Ealternative++;
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goto label;
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case 'O':
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/*
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* C99 locale modifiers.
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* The sequences
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* %Ec %EC %Ex %EX %Ey %EY
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* %Od %oe %OH %OI %Om %OM
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* %OS %Ou %OU %OV %Ow %OW %Oy
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* are supposed to provide alternate
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* representations.
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*
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* FreeBSD extension
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* %OB
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*/
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if (Ealternative || Oalternative)
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break;
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Oalternative++;
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goto label;
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case 'e':
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pt = _conv(t->tm_mday,
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fmt_padding[PAD_FMT_SDAYOFMONTH][PadIndex],
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pt, ptlim, loc);
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continue;
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case 'F':
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pt = _fmt("%Y-%m-%d", t, pt, ptlim, warnp, loc);
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continue;
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case 'H':
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pt = _conv(t->tm_hour, fmt_padding[PAD_FMT_HMS][PadIndex],
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pt, ptlim, loc);
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continue;
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case 'I':
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pt = _conv((t->tm_hour % 12) ?
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(t->tm_hour % 12) : 12,
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fmt_padding[PAD_FMT_HMS][PadIndex],
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pt, ptlim, loc);
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continue;
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case 'j':
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pt = _conv(t->tm_yday + 1,
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fmt_padding[PAD_FMT_DAYOFYEAR][PadIndex],
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pt, ptlim, loc);
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continue;
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case 'k':
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/*
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* This used to be...
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* _conv(t->tm_hour % 12 ?
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* t->tm_hour % 12 : 12, 2, ' ');
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* ...and has been changed to the below to
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* match SunOS 4.1.1 and Arnold Robbins'
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* strftime version 3.0. That is, "%k" and
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* "%l" have been swapped.
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* (ado, 1993-05-24)
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*/
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pt = _conv(t->tm_hour, fmt_padding[PAD_FMT_SHMS][PadIndex],
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pt, ptlim, loc);
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continue;
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#ifdef KITCHEN_SINK
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case 'K':
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/*
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** After all this time, still unclaimed!
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*/
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pt = _add("kitchen sink", pt, ptlim);
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continue;
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#endif /* defined KITCHEN_SINK */
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case 'l':
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/*
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* This used to be...
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* _conv(t->tm_hour, 2, ' ');
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* ...and has been changed to the below to
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* match SunOS 4.1.1 and Arnold Robbin's
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* strftime version 3.0. That is, "%k" and
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* "%l" have been swapped.
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* (ado, 1993-05-24)
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*/
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pt = _conv((t->tm_hour % 12) ?
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(t->tm_hour % 12) : 12,
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fmt_padding[PAD_FMT_SHMS][PadIndex],
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pt, ptlim, loc);
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continue;
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case 'M':
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pt = _conv(t->tm_min, fmt_padding[PAD_FMT_HMS][PadIndex],
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pt, ptlim, loc);
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continue;
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case 'm':
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pt = _conv(t->tm_mon + 1,
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fmt_padding[PAD_FMT_MONTH][PadIndex],
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pt, ptlim, loc);
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continue;
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case 'n':
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pt = _add("\n", pt, ptlim);
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continue;
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case 'p':
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pt = _add((t->tm_hour >= (HOURSPERDAY / 2)) ?
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tptr->pm : tptr->am,
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pt, ptlim);
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continue;
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case 'R':
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pt = _fmt("%H:%M", t, pt, ptlim, warnp, loc);
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continue;
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case 'r':
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pt = _fmt(tptr->ampm_fmt, t, pt, ptlim,
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warnp, loc);
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continue;
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case 'S':
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pt = _conv(t->tm_sec, fmt_padding[PAD_FMT_HMS][PadIndex],
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pt, ptlim, loc);
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continue;
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case 's':
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{
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struct tm tm;
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char buf[INT_STRLEN_MAXIMUM(
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time_t) + 1];
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time_t mkt;
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tm = *t;
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mkt = mktime(&tm);
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if (TYPE_SIGNED(time_t))
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(void) sprintf_l(buf, loc, "%ld",
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(long) mkt);
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else (void) sprintf_l(buf, loc, "%lu",
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(unsigned long) mkt);
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pt = _add(buf, pt, ptlim);
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}
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continue;
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case 'T':
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pt = _fmt("%H:%M:%S", t, pt, ptlim, warnp, loc);
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continue;
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case 't':
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pt = _add("\t", pt, ptlim);
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continue;
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case 'U':
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pt = _conv((t->tm_yday + DAYSPERWEEK -
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t->tm_wday) / DAYSPERWEEK,
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fmt_padding[PAD_FMT_WEEKOFYEAR][PadIndex],
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pt, ptlim, loc);
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continue;
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case 'u':
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/*
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* From Arnold Robbins' strftime version 3.0:
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* "ISO 8601: Weekday as a decimal number
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* [1 (Monday) - 7]"
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* (ado, 1993-05-24)
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*/
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pt = _conv((t->tm_wday == 0) ?
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DAYSPERWEEK : t->tm_wday,
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"%d", pt, ptlim, loc);
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continue;
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case 'V': /* ISO 8601 week number */
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case 'G': /* ISO 8601 year (four digits) */
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case 'g': /* ISO 8601 year (two digits) */
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/*
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* From Arnold Robbins' strftime version 3.0: "the week number of the
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* year (the first Monday as the first day of week 1) as a decimal number
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* (01-53)."
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* (ado, 1993-05-24)
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*
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* From "http://www.ft.uni-erlangen.de/~mskuhn/iso-time.html" by Markus Kuhn:
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* "Week 01 of a year is per definition the first week which has the
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* Thursday in this year, which is equivalent to the week which contains
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* the fourth day of January. In other words, the first week of a new year
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* is the week which has the majority of its days in the new year. Week 01
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* might also contain days from the previous year and the week before week
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* 01 of a year is the last week (52 or 53) of the previous year even if
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* it contains days from the new year. A week starts with Monday (day 1)
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* and ends with Sunday (day 7). For example, the first week of the year
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* 1997 lasts from 1996-12-30 to 1997-01-05..."
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* (ado, 1996-01-02)
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*/
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{
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int year;
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int base;
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int yday;
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int wday;
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int w;
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year = t->tm_year;
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base = TM_YEAR_BASE;
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yday = t->tm_yday;
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wday = t->tm_wday;
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for ( ; ; ) {
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int len;
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int bot;
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int top;
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len = isleap_sum(year, base) ?
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DAYSPERLYEAR :
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DAYSPERNYEAR;
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/*
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* What yday (-3 ... 3) does
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* the ISO year begin on?
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*/
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bot = ((yday + 11 - wday) %
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DAYSPERWEEK) - 3;
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/*
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* What yday does the NEXT
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* ISO year begin on?
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*/
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top = bot -
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(len % DAYSPERWEEK);
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if (top < -3)
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top += DAYSPERWEEK;
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top += len;
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if (yday >= top) {
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++base;
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w = 1;
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break;
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}
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if (yday >= bot) {
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w = 1 + ((yday - bot) /
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DAYSPERWEEK);
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break;
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}
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--base;
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yday += isleap_sum(year, base) ?
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DAYSPERLYEAR :
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DAYSPERNYEAR;
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}
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#ifdef XPG4_1994_04_09
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if ((w == 52 &&
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t->tm_mon == TM_JANUARY) ||
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(w == 1 &&
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t->tm_mon == TM_DECEMBER))
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w = 53;
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#endif /* defined XPG4_1994_04_09 */
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if (*format == 'V')
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pt = _conv(w, fmt_padding[PAD_FMT_WEEKOFYEAR][PadIndex],
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pt, ptlim, loc);
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else if (*format == 'g') {
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*warnp = IN_ALL;
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pt = _yconv(year, base, 0, 1,
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pt, ptlim, loc);
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} else pt = _yconv(year, base, 1, 1,
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pt, ptlim, loc);
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}
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continue;
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case 'v':
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/*
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* From Arnold Robbins' strftime version 3.0:
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* "date as dd-bbb-YYYY"
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* (ado, 1993-05-24)
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*/
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pt = _fmt("%e-%b-%Y", t, pt, ptlim, warnp, loc);
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continue;
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case 'W':
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pt = _conv((t->tm_yday + DAYSPERWEEK -
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(t->tm_wday ?
|
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(t->tm_wday - 1) :
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(DAYSPERWEEK - 1))) / DAYSPERWEEK,
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fmt_padding[PAD_FMT_WEEKOFYEAR][PadIndex],
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pt, ptlim, loc);
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continue;
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case 'w':
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pt = _conv(t->tm_wday, "%d", pt, ptlim, loc);
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continue;
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case 'X':
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pt = _fmt(tptr->X_fmt, t, pt, ptlim, warnp, loc);
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continue;
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case 'x':
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{
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int warn2 = IN_SOME;
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pt = _fmt(tptr->x_fmt, t, pt, ptlim, &warn2, loc);
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if (warn2 == IN_ALL)
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warn2 = IN_THIS;
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if (warn2 > *warnp)
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*warnp = warn2;
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}
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continue;
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case 'y':
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*warnp = IN_ALL;
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pt = _yconv(t->tm_year, TM_YEAR_BASE, 0, 1,
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pt, ptlim, loc);
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continue;
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case 'Y':
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pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 1,
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pt, ptlim, loc);
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continue;
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case 'Z':
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#ifdef TM_ZONE
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if (t->TM_ZONE != NULL)
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pt = _add(t->TM_ZONE, pt, ptlim);
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else
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#endif /* defined TM_ZONE */
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if (t->tm_isdst >= 0)
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pt = _add(tzname[t->tm_isdst != 0],
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pt, ptlim);
|
|
/*
|
|
* C99 says that %Z must be replaced by the
|
|
* empty string if the time zone is not
|
|
* determinable.
|
|
*/
|
|
continue;
|
|
case 'z':
|
|
{
|
|
int diff;
|
|
char const * sign;
|
|
|
|
if (t->tm_isdst < 0)
|
|
continue;
|
|
#ifdef TM_GMTOFF
|
|
diff = t->TM_GMTOFF;
|
|
#else /* !defined TM_GMTOFF */
|
|
/*
|
|
* C99 says that the UTC offset must
|
|
* be computed by looking only at
|
|
* tm_isdst. This requirement is
|
|
* incorrect, since it means the code
|
|
* must rely on magic (in this case
|
|
* altzone and timezone), and the
|
|
* magic might not have the correct
|
|
* offset. Doing things correctly is
|
|
* tricky and requires disobeying C99;
|
|
* see GNU C strftime for details.
|
|
* For now, punt and conform to the
|
|
* standard, even though it's incorrect.
|
|
*
|
|
* C99 says that %z must be replaced by the
|
|
* empty string if the time zone is not
|
|
* determinable, so output nothing if the
|
|
* appropriate variables are not available.
|
|
*/
|
|
if (t->tm_isdst == 0)
|
|
#ifdef USG_COMPAT
|
|
diff = -timezone;
|
|
#else /* !defined USG_COMPAT */
|
|
continue;
|
|
#endif /* !defined USG_COMPAT */
|
|
else
|
|
#ifdef ALTZONE
|
|
diff = -altzone;
|
|
#else /* !defined ALTZONE */
|
|
continue;
|
|
#endif /* !defined ALTZONE */
|
|
#endif /* !defined TM_GMTOFF */
|
|
if (diff < 0) {
|
|
sign = "-";
|
|
diff = -diff;
|
|
} else
|
|
sign = "+";
|
|
pt = _add(sign, pt, ptlim);
|
|
diff /= SECSPERMIN;
|
|
diff = (diff / MINSPERHOUR) * 100 +
|
|
(diff % MINSPERHOUR);
|
|
pt = _conv(diff,
|
|
fmt_padding[PAD_FMT_YEAR][PadIndex],
|
|
pt, ptlim, loc);
|
|
}
|
|
continue;
|
|
case '+':
|
|
pt = _fmt(tptr->date_fmt, t, pt, ptlim,
|
|
warnp, loc);
|
|
continue;
|
|
case '-':
|
|
if (PadIndex != PAD_DEFAULT)
|
|
break;
|
|
PadIndex = PAD_LESS;
|
|
goto label;
|
|
case '_':
|
|
if (PadIndex != PAD_DEFAULT)
|
|
break;
|
|
PadIndex = PAD_SPACE;
|
|
goto label;
|
|
case '0':
|
|
if (PadIndex != PAD_DEFAULT)
|
|
break;
|
|
PadIndex = PAD_ZERO;
|
|
goto label;
|
|
case '%':
|
|
/*
|
|
* X311J/88-090 (4.12.3.5): if conversion char is
|
|
* undefined, behavior is undefined. Print out the
|
|
* character itself as printf(3) also does.
|
|
*/
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
if (pt == ptlim)
|
|
break;
|
|
*pt++ = *format;
|
|
}
|
|
return (pt);
|
|
}
|
|
|
|
static char *
|
|
_conv(const int n, const char * const format, char * const pt,
|
|
const char * const ptlim, locale_t loc)
|
|
{
|
|
char buf[INT_STRLEN_MAXIMUM(int) + 1];
|
|
|
|
(void) sprintf_l(buf, loc, format, n);
|
|
return _add(buf, pt, ptlim);
|
|
}
|
|
|
|
static char *
|
|
_add(const char *str, char *pt, const char * const ptlim)
|
|
{
|
|
while (pt < ptlim && (*pt = *str++) != '\0')
|
|
++pt;
|
|
return (pt);
|
|
}
|
|
|
|
/*
|
|
* POSIX and the C Standard are unclear or inconsistent about
|
|
* what %C and %y do if the year is negative or exceeds 9999.
|
|
* Use the convention that %C concatenated with %y yields the
|
|
* same output as %Y, and that %Y contains at least 4 bytes,
|
|
* with more only if necessary.
|
|
*/
|
|
|
|
static char *
|
|
_yconv(const int a, const int b, const int convert_top, const int convert_yy,
|
|
char *pt, const char * const ptlim, locale_t loc)
|
|
{
|
|
register int lead;
|
|
register int trail;
|
|
|
|
#define DIVISOR 100
|
|
trail = a % DIVISOR + b % DIVISOR;
|
|
lead = a / DIVISOR + b / DIVISOR + trail / DIVISOR;
|
|
trail %= DIVISOR;
|
|
if (trail < 0 && lead > 0) {
|
|
trail += DIVISOR;
|
|
--lead;
|
|
} else if (lead < 0 && trail > 0) {
|
|
trail -= DIVISOR;
|
|
++lead;
|
|
}
|
|
if (convert_top) {
|
|
if (lead == 0 && trail < 0)
|
|
pt = _add("-0", pt, ptlim);
|
|
else pt = _conv(lead, "%02d", pt, ptlim, loc);
|
|
}
|
|
if (convert_yy)
|
|
pt = _conv(((trail < 0) ? -trail : trail), "%02d", pt,
|
|
ptlim, loc);
|
|
return (pt);
|
|
}
|