File: [cvs.NetBSD.org] / src / lib / libc / time / strftime.c (download)
Revision 1.28, Wed Jul 17 23:09:26 2013 UTC (10 years, 9 months ago) by christos
Branch: MAIN
CVS Tags: riastradh-drm2-base2, riastradh-drm2-base1
Changes since 1.27: +4 -4
lines
remove "register" in new code
fix backwards check for overflow
|
/* $NetBSD: strftime.c,v 1.28 2013/07/17 23:09:26 christos Exp $ */
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char elsieid[] = "@(#)strftime.c 7.64";
static char elsieid[] = "@(#)strftime.c 8.3";
#else
__RCSID("$NetBSD: strftime.c,v 1.28 2013/07/17 23:09:26 christos Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
#include "namespace.h"
#include <stddef.h>
#include <locale.h>
#include "setlocale_local.h"
/*
** Based on the UCB version with the copyright notice and sccsid
** appearing below.
**
** This is ANSIish only when "multibyte character == plain character".
*/
#include "private.h"
/*
** We don't use these extensions in strftime operation even when
** supported by the local tzcode configuration. A strictly
** conforming C application may leave them in undefined state.
*/
#ifdef _LIBC
#undef TM_ZONE
#undef TM_GMTOFF
#endif
/*
** Copyright (c) 1989, 1993
** The Regents of the University of California. All rights reserved.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
** 1. Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** 2. Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in the
** documentation and/or other materials provided with the distribution.
** 3. All advertising materials mentioning features or use of this software
** must display the following acknowledgement:
** This product includes software developed by the University of
** California, Berkeley and its contributors.
** 4. Neither the name of the University nor the names of its contributors
** may be used to endorse or promote products derived from this software
** without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
** ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
** OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
** HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
** SUCH DAMAGE.
*/
#ifndef LIBC_SCCS
#ifndef lint
static const char sccsid[] = "@(#)strftime.c 5.4 (Berkeley) 3/14/89";
#endif /* !defined lint */
#endif /* !defined LIBC_SCCS */
#include "tzfile.h"
#include "fcntl.h"
#include "locale.h"
#ifdef __weak_alias
__weak_alias(strftime_l, _strftime_l)
__weak_alias(strftime_lz, _strftime_lz)
__weak_alias(strftime_z, _strftime_z)
#endif
#include "sys/localedef.h"
#define _TIME_LOCALE(loc) \
((_TimeLocale *)((loc)->part_impl[(size_t)LC_TIME]))
#define c_fmt d_t_fmt
static char * _add(const char *, char *, const char *);
static char * _conv(int, const char *, char *, const char *);
static char * _fmt(const timezone_t, const char *, const struct tm *, char *,
const char *, int *, locale_t);
static char * _yconv(int, int, int, int, char *, const char *);
extern char * tzname[];
#ifndef YEAR_2000_NAME
#define YEAR_2000_NAME "CHECK_STRFTIME_FORMATS_FOR_TWO_DIGIT_YEARS"
#endif /* !defined YEAR_2000_NAME */
#define IN_NONE 0
#define IN_SOME 1
#define IN_THIS 2
#define IN_ALL 3
size_t
strftime_z(const timezone_t sp, char * __restrict s, size_t maxsize,
const char * __restrict format, const struct tm * __restrict t)
{
return strftime_lz(sp, s, maxsize, format, t, _current_locale());
}
size_t
strftime_lz(const timezone_t sp, char *const s, const size_t maxsize,
const char *const format, const struct tm *const t, locale_t loc)
{
char * p;
int warn;
warn = IN_NONE;
p = _fmt(sp, ((format == NULL) ? "%c" : format), t, s, s + maxsize,
&warn, loc);
#ifndef NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU
if (warn != IN_NONE && getenv(YEAR_2000_NAME) != NULL) {
(void) fprintf(stderr, "\n");
if (format == NULL)
(void) fprintf(stderr, "NULL strftime format ");
else (void) fprintf(stderr, "strftime format \"%s\" ",
format);
(void) fprintf(stderr, "yields only two digits of years in ");
if (warn == IN_SOME)
(void) fprintf(stderr, "some locales");
else if (warn == IN_THIS)
(void) fprintf(stderr, "the current locale");
else (void) fprintf(stderr, "all locales");
(void) fprintf(stderr, "\n");
}
#endif /* !defined NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU */
if (p == s + maxsize)
return 0;
*p = '\0';
return p - s;
}
static char *
_fmt(const timezone_t sp, const char *format, const struct tm *const t,
char *pt, const char *const ptlim, int *warnp, locale_t loc)
{
for ( ; *format; ++format) {
if (*format == '%') {
label:
switch (*++format) {
case '\0':
--format;
break;
case 'A':
pt = _add((t->tm_wday < 0 ||
t->tm_wday >= DAYSPERWEEK) ?
"?" : _TIME_LOCALE(loc)->day[t->tm_wday],
pt, ptlim);
continue;
case 'a':
pt = _add((t->tm_wday < 0 ||
t->tm_wday >= DAYSPERWEEK) ?
"?" : _TIME_LOCALE(loc)->abday[t->tm_wday],
pt, ptlim);
continue;
case 'B':
pt = _add((t->tm_mon < 0 ||
t->tm_mon >= MONSPERYEAR) ?
"?" : _TIME_LOCALE(loc)->mon[t->tm_mon],
pt, ptlim);
continue;
case 'b':
case 'h':
pt = _add((t->tm_mon < 0 ||
t->tm_mon >= MONSPERYEAR) ?
"?" : _TIME_LOCALE(loc)->abmon[t->tm_mon],
pt, ptlim);
continue;
case 'C':
/*
** %C used to do a...
** _fmt("%a %b %e %X %Y", t);
** ...whereas now POSIX 1003.2 calls for
** something completely different.
** (ado, 1993-05-24)
*/
pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 0,
pt, ptlim);
continue;
case 'c':
{
int warn2 = IN_SOME;
pt = _fmt(sp, _TIME_LOCALE(loc)->c_fmt, t, pt,
ptlim, &warn2, loc);
if (warn2 == IN_ALL)
warn2 = IN_THIS;
if (warn2 > *warnp)
*warnp = warn2;
}
continue;
case 'D':
pt = _fmt(sp, "%m/%d/%y", t, pt, ptlim, warnp,
loc);
continue;
case 'd':
pt = _conv(t->tm_mday, "%02d", pt, ptlim);
continue;
case 'E':
case 'O':
/*
** C99 locale modifiers.
** The sequences
** %Ec %EC %Ex %EX %Ey %EY
** %Od %oe %OH %OI %Om %OM
** %OS %Ou %OU %OV %Ow %OW %Oy
** are supposed to provide alternate
** representations.
*/
goto label;
case 'e':
pt = _conv(t->tm_mday, "%2d", pt, ptlim);
continue;
case 'F':
pt = _fmt(sp, "%Y-%m-%d", t, pt, ptlim, warnp,
loc);
continue;
case 'H':
pt = _conv(t->tm_hour, "%02d", pt, ptlim);
continue;
case 'I':
pt = _conv((t->tm_hour % 12) ?
(t->tm_hour % 12) : 12,
"%02d", pt, ptlim);
continue;
case 'j':
pt = _conv(t->tm_yday + 1, "%03d", pt, ptlim);
continue;
case 'k':
/*
** This used to be...
** _conv(t->tm_hour % 12 ?
** t->tm_hour % 12 : 12, 2, ' ');
** ...and has been changed to the below to
** match SunOS 4.1.1 and Arnold Robbins'
** strftime version 3.0. That is, "%k" and
** "%l" have been swapped.
** (ado, 1993-05-24)
*/
pt = _conv(t->tm_hour, "%2d", pt, ptlim);
continue;
#ifdef KITCHEN_SINK
case 'K':
/*
** After all this time, still unclaimed!
*/
pt = _add("kitchen sink", pt, ptlim);
continue;
#endif /* defined KITCHEN_SINK */
case 'l':
/*
** This used to be...
** _conv(t->tm_hour, 2, ' ');
** ...and has been changed to the below to
** match SunOS 4.1.1 and Arnold Robbin's
** strftime version 3.0. That is, "%k" and
** "%l" have been swapped.
** (ado, 1993-05-24)
*/
pt = _conv((t->tm_hour % 12) ?
(t->tm_hour % 12) : 12,
"%2d", pt, ptlim);
continue;
case 'M':
pt = _conv(t->tm_min, "%02d", pt, ptlim);
continue;
case 'm':
pt = _conv(t->tm_mon + 1, "%02d", pt, ptlim);
continue;
case 'n':
pt = _add("\n", pt, ptlim);
continue;
case 'p':
pt = _add((t->tm_hour >= (HOURSPERDAY / 2)) ?
_TIME_LOCALE(loc)->am_pm[1] :
_TIME_LOCALE(loc)->am_pm[0],
pt, ptlim);
continue;
case 'R':
pt = _fmt(sp, "%H:%M", t, pt, ptlim, warnp,
loc);
continue;
case 'r':
pt = _fmt(sp, _TIME_LOCALE(loc)->t_fmt_ampm, t,
pt, ptlim, warnp, loc);
continue;
case 'S':
pt = _conv(t->tm_sec, "%02d", pt, ptlim);
continue;
case 's':
{
struct tm tm;
char buf[INT_STRLEN_MAXIMUM(
time_t) + 1];
time_t mkt;
tm = *t;
mkt = mktime(&tm);
/* CONSTCOND */
if (TYPE_SIGNED(time_t))
(void)snprintf(buf, sizeof(buf),
"%jd", (intmax_t) mkt);
else (void)snprintf(buf, sizeof(buf),
"%ju", (uintmax_t) mkt);
pt = _add(buf, pt, ptlim);
}
continue;
case 'T':
pt = _fmt(sp, "%H:%M:%S", t, pt, ptlim, warnp,
loc);
continue;
case 't':
pt = _add("\t", pt, ptlim);
continue;
case 'U':
pt = _conv((t->tm_yday + DAYSPERWEEK -
t->tm_wday) / DAYSPERWEEK,
"%02d", pt, ptlim);
continue;
case 'u':
/*
** From Arnold Robbins' strftime version 3.0:
** "ISO 8601: Weekday as a decimal number
** [1 (Monday) - 7]"
** (ado, 1993-05-24)
*/
pt = _conv((t->tm_wday == 0) ?
DAYSPERWEEK : t->tm_wday,
"%d", pt, ptlim);
continue;
case 'V': /* ISO 8601 week number */
case 'G': /* ISO 8601 year (four digits) */
case 'g': /* ISO 8601 year (two digits) */
/*
** From Arnold Robbins' strftime version 3.0: "the week number of the
** year (the first Monday as the first day of week 1) as a decimal number
** (01-53)."
** (ado, 1993-05-24)
**
** From "http://www.ft.uni-erlangen.de/~mskuhn/iso-time.html" by Markus Kuhn:
** "Week 01 of a year is per definition the first week which has the
** Thursday in this year, which is equivalent to the week which contains
** the fourth day of January. In other words, the first week of a new year
** is the week which has the majority of its days in the new year. Week 01
** might also contain days from the previous year and the week before week
** 01 of a year is the last week (52 or 53) of the previous year even if
** it contains days from the new year. A week starts with Monday (day 1)
** and ends with Sunday (day 7). For example, the first week of the year
** 1997 lasts from 1996-12-30 to 1997-01-05..."
** (ado, 1996-01-02)
*/
{
int year;
int base;
int yday;
int wday;
int w;
year = t->tm_year;
base = TM_YEAR_BASE;
yday = t->tm_yday;
wday = t->tm_wday;
for ( ; ; ) {
int len;
int bot;
int top;
len = isleap_sum(year, base) ?
DAYSPERLYEAR :
DAYSPERNYEAR;
/*
** What yday (-3 ... 3) does
** the ISO year begin on?
*/
bot = ((yday + 11 - wday) %
DAYSPERWEEK) - 3;
/*
** What yday does the NEXT
** ISO year begin on?
*/
top = bot -
(len % DAYSPERWEEK);
if (top < -3)
top += DAYSPERWEEK;
top += len;
if (yday >= top) {
++base;
w = 1;
break;
}
if (yday >= bot) {
w = 1 + ((yday - bot) /
DAYSPERWEEK);
break;
}
--base;
yday += isleap_sum(year, base) ?
DAYSPERLYEAR :
DAYSPERNYEAR;
}
#ifdef XPG4_1994_04_09
if ((w == 52 &&
t->tm_mon == TM_JANUARY) ||
(w == 1 &&
t->tm_mon == TM_DECEMBER))
w = 53;
#endif /* defined XPG4_1994_04_09 */
if (*format == 'V')
pt = _conv(w, "%02d",
pt, ptlim);
else if (*format == 'g') {
*warnp = IN_ALL;
pt = _yconv(year, base, 0, 1,
pt, ptlim);
} else pt = _yconv(year, base, 1, 1,
pt, ptlim);
}
continue;
case 'v':
/*
** From Arnold Robbins' strftime version 3.0:
** "date as dd-bbb-YYYY"
** (ado, 1993-05-24)
*/
pt = _fmt(sp, "%e-%b-%Y", t, pt, ptlim, warnp,
loc);
continue;
case 'W':
pt = _conv((t->tm_yday + DAYSPERWEEK -
(t->tm_wday ?
(t->tm_wday - 1) :
(DAYSPERWEEK - 1))) / DAYSPERWEEK,
"%02d", pt, ptlim);
continue;
case 'w':
pt = _conv(t->tm_wday, "%d", pt, ptlim);
continue;
case 'X':
pt = _fmt(sp, _TIME_LOCALE(loc)->t_fmt, t, pt,
ptlim, warnp, loc);
continue;
case 'x':
{
int warn2 = IN_SOME;
pt = _fmt(sp, _TIME_LOCALE(loc)->d_fmt, t, pt,
ptlim, &warn2, loc);
if (warn2 == IN_ALL)
warn2 = IN_THIS;
if (warn2 > *warnp)
*warnp = warn2;
}
continue;
case 'y':
*warnp = IN_ALL;
pt = _yconv(t->tm_year, TM_YEAR_BASE, 0, 1,
pt, ptlim);
continue;
case 'Y':
pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 1,
pt, ptlim);
continue;
case 'Z':
#ifdef TM_ZONE
if (t->TM_ZONE != NULL)
pt = _add(t->TM_ZONE, pt, ptlim);
else
#endif /* defined TM_ZONE */
if (t->tm_isdst >= 0)
pt = _add((sp ?
tzgetname(sp, t->tm_isdst) :
tzname[t->tm_isdst != 0]),
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 = (int)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.
*/
#ifndef STD_INSPIRED
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 */
#else /* defined STD_INSPIRED */
{
struct tm tmp;
time_t lct, gct;
/*
** Get calendar time from t
** being treated as local.
*/
tmp = *t; /* mktime discards const */
lct = mktime(&tmp);
if (lct == (time_t)-1)
continue;
/*
** Get calendar time from t
** being treated as GMT.
**/
tmp = *t; /* mktime discards const */
gct = timegm(&tmp);
if (gct == (time_t)-1)
continue;
/* LINTED difference will fit int */
diff = (intmax_t)gct - (intmax_t)lct;
}
#endif /* defined STD_INSPIRED */
#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, "%04d", pt, ptlim);
}
continue;
#if 0
case '+':
pt = _fmt(sp, _TIME_LOCALE(loc)->date_fmt, t,
pt, ptlim, warnp, loc);
continue;
#endif
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;
}
size_t
strftime(char * const s, const size_t maxsize,
const char * const format, const struct tm * const t)
{
tzset();
return strftime_z(NULL, s, maxsize, format, t);
}
size_t
strftime_l(char * __restrict s, size_t maxsize, const char * __restrict format,
const struct tm * __restrict t, locale_t loc)
{
tzset();
return strftime_lz(NULL, s, maxsize, format, t, loc);
}
static char *
_conv(const int n, const char *const format, char *const pt,
const char *const ptlim)
{
char buf[INT_STRLEN_MAXIMUM(int) + 1];
(void) snprintf(buf, sizeof(buf), 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)
{
int lead;
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);
}
if (convert_yy)
pt = _conv(((trail < 0) ? -trail : trail), "%02d", pt, ptlim);
return pt;
}
#ifdef LOCALE_HOME
static struct lc_time_T *
_loc(void)
{
static const char locale_home[] = LOCALE_HOME;
static const char lc_time[] = "LC_TIME";
static char * locale_buf;
int fd;
int oldsun; /* "...ain't got nothin' to do..." */
char * lbuf;
char * name;
char * p;
const char ** ap;
const char * plim;
char filename[FILENAME_MAX];
struct stat st;
size_t namesize;
size_t bufsize;
/*
** Use localebuf.mon[0] to signal whether locale is already set up.
*/
if (localebuf.mon[0])
return &localebuf;
name = setlocale(LC_TIME, NULL);
if (name == NULL || *name == '\0')
goto no_locale;
/*
** If the locale name is the same as our cache, use the cache.
*/
lbuf = locale_buf;
if (lbuf != NULL && strcmp(name, lbuf) == 0) {
p = lbuf;
for (ap = (const char **) &localebuf;
ap < (const char **) (&localebuf + 1);
++ap)
*ap = p += strlen(p) + 1;
return &localebuf;
}
/*
** Slurp the locale file into the cache.
*/
namesize = strlen(name) + 1;
if (sizeof filename <
((sizeof locale_home) + namesize + (sizeof lc_time)))
goto no_locale;
oldsun = 0;
(void) sprintf(filename, "%s/%s/%s", locale_home, name, lc_time);
fd = open(filename, O_RDONLY);
if (fd < 0) {
/*
** Old Sun systems have a different naming and data convention.
*/
oldsun = 1;
(void) sprintf(filename, "%s/%s/%s", locale_home,
lc_time, name);
fd = open(filename, O_RDONLY);
if (fd < 0)
goto no_locale;
}
if (fstat(fd, &st) != 0)
goto bad_locale;
if (st.st_size <= 0)
goto bad_locale;
bufsize = namesize + st.st_size;
locale_buf = NULL;
lbuf = (lbuf == NULL) ? malloc(bufsize) : realloc(lbuf, bufsize);
if (lbuf == NULL)
goto bad_locale;
(void) strcpy(lbuf, name);
p = lbuf + namesize;
plim = p + st.st_size;
if (read(fd, p, (size_t) st.st_size) != st.st_size)
goto bad_lbuf;
if (close(fd) != 0)
goto bad_lbuf;
/*
** Parse the locale file into localebuf.
*/
if (plim[-1] != '\n')
goto bad_lbuf;
for (ap = (const char **) &localebuf;
ap < (const char **) (&localebuf + 1);
++ap) {
if (p == plim)
goto bad_lbuf;
*ap = p;
while (*p != '\n')
++p;
*p++ = '\0';
}
if (oldsun) {
/*
** SunOS 4 used an obsolescent format; see localdtconv(3).
** c_fmt had the ``short format for dates and times together''
** (SunOS 4 date, "%a %b %e %T %Z %Y" in the C locale);
** date_fmt had the ``long format for dates''
** (SunOS 4 strftime %C, "%A, %B %e, %Y" in the C locale).
** Discard the latter in favor of the former.
*/
localebuf.date_fmt = localebuf.c_fmt;
}
/*
** Record the successful parse in the cache.
*/
locale_buf = lbuf;
return &localebuf;
bad_lbuf:
free(lbuf);
bad_locale:
(void) close(fd);
no_locale:
localebuf = C_time_locale;
locale_buf = NULL;
return &localebuf;
}
#endif /* defined LOCALE_HOME */
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