freebsd-dev/lib/libc/stdtime/strftime.c

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/*
* Copyright (c) 1989 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#ifdef LIBC_RCS
static const char rcsid[] =
"$Id: strftime.c,v 1.9 1996/07/12 18:55:32 jkh Exp $";
#endif
#ifndef lint
#ifndef NOID
static const char elsieid[] = "@(#)strftime.c 7.38";
/*
** Based on the UCB version with the ID appearing below.
** This is ANSIish only when "multibyte character == plain character".
*/
#endif /* !defined NOID */
#endif /* !defined lint */
#include "private.h"
#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>
#include <rune.h> /* for _PATH_LOCALE */
#include <sys/stat.h>
#define LOCALE_HOME _PATH_LOCALE
struct lc_time_T {
const char * mon[12];
const char * month[12];
const char * wday[7];
const char * weekday[7];
const char * X_fmt;
const char * x_fmt;
const char * c_fmt;
const char * am;
const char * pm;
const char * date_fmt;
};
static struct lc_time_T localebuf;
static int using_locale;
#define Locale (using_locale ? &localebuf : &C_time_locale)
static const struct lc_time_T C_time_locale = {
{
"Jan", "Feb", "Mar", "Apr", "May", "Jun",
"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
}, {
"January", "February", "March", "April", "May", "June",
"July", "August", "September", "October", "November", "December"
}, {
"Sun", "Mon", "Tue", "Wed",
"Thu", "Fri", "Sat"
}, {
"Sunday", "Monday", "Tuesday", "Wednesday",
"Thursday", "Friday", "Saturday"
},
/* X_fmt */
"%H:%M:%S",
/*
** x_fmt
** Since the C language standard calls for
** "date, using locale's date format," anything goes.
** Using just numbers (as here) makes Quakers happier;
** it's also compatible with SVR4.
*/
"%m/%d/%y",
/*
** c_fmt (ctime-compatible)
** Note that
** "%a %b %d %H:%M:%S %Y"
** is used by Solaris 2.3.
*/
"%a %b %e %X %Y",
/* am */
"AM",
/* pm */
"PM",
/* date_fmt */
"%a %b %e %X %Z %Y"
};
static char * _add P((const char *, char *, const char *));
static char * _conv P((int, const char *, char *, const char *));
static char * _fmt P((const char *, const struct tm *, char *, const char *));
static char * _secs P((const struct tm *, char *, const char *));
size_t strftime P((char *, size_t, const char *, const struct tm *));
extern char * tzname[];
size_t
strftime(s, maxsize, format, t)
char *const s;
const size_t maxsize;
const char *const format;
const struct tm *const t;
{
char *p;
tzset();
p = _fmt(((format == NULL) ? "%c" : format), t, s, s + maxsize);
if (p == s + maxsize)
return 0;
*p = '\0';
return p - s;
}
static char *
_fmt(format, t, pt, ptlim)
const char *format;
const struct tm *const t;
char *pt;
const char *const ptlim;
{
for ( ; *format; ++format) {
if (*format == '%') {
label:
switch (*++format) {
case '\0':
--format;
break;
case 'A':
pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ?
"?" : Locale->weekday[t->tm_wday],
pt, ptlim);
continue;
case 'a':
pt = _add((t->tm_wday < 0 || t->tm_wday > 6) ?
"?" : Locale->wday[t->tm_wday],
pt, ptlim);
continue;
case 'B':
pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ?
"?" : Locale->month[t->tm_mon],
pt, ptlim);
continue;
case 'b':
case 'h':
pt = _add((t->tm_mon < 0 || t->tm_mon > 11) ?
"?" : Locale->mon[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, 5/24/93)
*/
pt = _conv((t->tm_year + TM_YEAR_BASE) / 100,
"%02d", pt, ptlim);
continue;
case 'c':
pt = _fmt(Locale->c_fmt, t, pt, ptlim);
continue;
case 'D':
pt = _fmt("%m/%d/%y", t, pt, ptlim);
continue;
case 'd':
pt = _conv(t->tm_mday, "%02d", pt, ptlim);
continue;
case 'E':
case 'O':
/*
** POSIX locale extensions, a la
** Arnold Robbins' strftime version 3.0.
** The sequences
** %Ec %EC %Ex %Ey %EY
** %Od %oe %OH %OI %Om %OM
** %OS %Ou %OU %OV %Ow %OW %Oy
** are supposed to provide alternate
** representations.
** (ado, 5/24/93)
*/
goto label;
case 'e':
pt = _conv(t->tm_mday, "%2d", pt, ptlim);
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, 5/24/93)
*/
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, 5/24/93)
*/
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 >= 12) ?
Locale->pm :
Locale->am,
pt, ptlim);
continue;
case 'R':
pt = _fmt("%H:%M", t, pt, ptlim);
continue;
case 'r':
pt = _fmt("%I:%M:%S %p", t, pt, ptlim);
continue;
case 'S':
pt = _conv(t->tm_sec, "%02d", pt, ptlim);
continue;
case 's':
pt = _secs(t, pt, ptlim);
continue;
case 'T':
pt = _fmt("%H:%M:%S", t, pt, ptlim);
continue;
case 't':
pt = _add("\t", pt, ptlim);
continue;
case 'U':
pt = _conv((t->tm_yday + 7 - t->tm_wday) / 7,
"%02d", pt, ptlim);
continue;
case 'u':
/*
** From Arnold Robbins' strftime version 3.0:
** "ISO 8601: Weekday as a decimal number
** [1 (Monday) - 7]"
** (ado, 5/24/93)
*/
pt = _conv((t->tm_wday == 0) ? 7 : t->tm_wday,
"%d", pt, ptlim);
continue;
case 'V':
/*
** 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). The method for
** determining the week number is as specified
** by ISO 8601 (to wit: if the week containing
** January 1 has four or more days in the new
** year, then it is week 1, otherwise it is
** week 53 of the previous year and the next
** week is week 1)."
** (ado, 5/24/93)
*/
/*
** XXX--If January 1 falls on a Friday,
** January 1-3 are part of week 53 of the
** previous year. By analogy, if January
** 1 falls on a Thursday, are December 29-31
** of the PREVIOUS year part of week 1???
** (ado 5/24/93)
*/
/*
** You are understood not to expect this.
*/
{
int i;
i = (t->tm_yday + 10 - (t->tm_wday ?
(t->tm_wday - 1) : 6)) / 7;
if (i == 0) {
/*
** What day of the week does
** January 1 fall on?
*/
i = t->tm_wday -
(t->tm_yday - 1);
/*
** Fri Jan 1: 53
** Sun Jan 1: 52
** Sat Jan 1: 53 if previous
** year a leap
** year, else 52
*/
if (i == TM_FRIDAY)
i = 53;
else if (i == TM_SUNDAY)
i = 52;
else i = isleap(t->tm_year +
TM_YEAR_BASE) ?
53 : 52;
#ifdef XPG4_1994_04_09
/*
** As of 4/9/94, though,
** XPG4 calls for 53
** unconditionally.
*/
i = 53;
#endif /* defined XPG4_1994_04_09 */
}
pt = _conv(i, "%02d", pt, ptlim);
}
continue;
case 'v':
/*
** From Arnold Robbins' strftime version 3.0:
** "date as dd-bbb-YYYY"
** (ado, 5/24/93)
*/
pt = _fmt("%e-%b-%Y", t, pt, ptlim);
continue;
case 'W':
pt = _conv((t->tm_yday + 7 -
(t->tm_wday ?
(t->tm_wday - 1) : 6)) / 7,
"%02d", pt, ptlim);
continue;
case 'w':
pt = _conv(t->tm_wday, "%d", pt, ptlim);
continue;
case 'X':
pt = _fmt(Locale->X_fmt, t, pt, ptlim);
continue;
case 'x':
pt = _fmt(Locale->x_fmt, t, pt, ptlim);
continue;
case 'y':
pt = _conv((t->tm_year + TM_YEAR_BASE) % 100,
"%02d", pt, ptlim);
continue;
case 'Y':
pt = _conv(t->tm_year + TM_YEAR_BASE, "%04d",
pt, ptlim);
continue;
case 'Z':
if (t->tm_zone != NULL)
pt = _add(t->tm_zone, pt, ptlim);
else
if (t->tm_isdst == 0 || t->tm_isdst == 1) {
pt = _add(tzname[t->tm_isdst],
pt, ptlim);
} else pt = _add("?", pt, ptlim);
continue;
case '+':
pt = _fmt(Locale->date_fmt, t, pt, ptlim);
continue;
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(n, format, pt, ptlim)
const int n;
const char *const format;
char *const pt;
const char *const ptlim;
{
char buf[INT_STRLEN_MAXIMUM(int) + 1];
(void) sprintf(buf, format, n);
return _add(buf, pt, ptlim);
}
static char *
_secs(t, pt, ptlim)
const struct tm *t;
char *pt;
const char *ptlim;
{
char buf[INT_STRLEN_MAXIMUM(int) + 1];
register time_t s;
struct tm tmp;
/* Make a copy, mktime(3) modifies the tm struct. */
tmp = *t;
s = mktime(&tmp);
(void) sprintf(buf, "%ld", s);
return _add(buf, pt, ptlim);
}
static char *
_add(str, pt, ptlim)
const char *str;
char *pt;
const char *const ptlim;
{
while (pt < ptlim && (*pt = *str++) != '\0')
++pt;
return pt;
}
extern char *_PathLocale;
int
__time_load_locale(const char *name)
{
static const char lc_time[] = "LC_TIME";
static char * locale_buf;
static char locale_buf_C[] = "C";
int fd;
char * lbuf;
char * p;
const char ** ap;
const char * plim;
char filename[FILENAME_MAX];
struct stat st;
size_t namesize;
size_t bufsize;
int save_using_locale;
save_using_locale = using_locale;
using_locale = 0;
if (name == NULL)
goto no_locale;
if (!*name || !strcmp(name, "C") || !strcmp(name, "POSIX"))
return 0;
/*
** 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;
using_locale = 1;
return 0;
}
/*
** Slurp the locale file into the cache.
*/
namesize = strlen(name) + 1;
snprintf(filename, sizeof filename,
"%s/%s/%s",
_PathLocale, name, lc_time);
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 || lbuf == locale_buf_C) ?
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 reset_locale;
*ap = p;
while (*p != '\n')
++p;
*p++ = '\0';
}
/*
** Record the successful parse in the cache.
*/
locale_buf = lbuf;
using_locale = 1;
return 0;
reset_locale:
/*
* XXX - This may not be the correct thing to do in this case.
* setlocale() assumes that we left the old locale alone.
*/
locale_buf = locale_buf_C;
localebuf = C_time_locale;
save_using_locale = 0;
bad_lbuf:
free(lbuf);
bad_locale:
(void) close(fd);
no_locale:
using_locale = save_using_locale;
return -1;
}