freebsd-dev/lib/libc/stdtime/strptime.c
Mike Makonnen 6c688436bb Backout my changes in rev. 1.32 and 1.33. There is some code that depends
on the previous behaviour. This also brings strptime(3) behaviour back in line
with the other BSDs.

Approved by:	markm (mentor)
2003-04-30 10:25:57 +00:00

532 lines
11 KiB
C

/*
* Powerdog Industries kindly requests feedback from anyone modifying
* this function:
*
* Date: Thu, 05 Jun 1997 23:17:17 -0400
* From: Kevin Ruddy <kevin.ruddy@powerdog.com>
* To: James FitzGibbon <james@nexis.net>
* Subject: Re: Use of your strptime(3) code (fwd)
*
* The reason for the "no mod" clause was so that modifications would
* come back and we could integrate them and reissue so that a wider
* audience could use it (thereby spreading the wealth). This has
* made it possible to get strptime to work on many operating systems.
* I'm not sure why that's "plain unacceptable" to the FreeBSD team.
*
* Anyway, you can change it to "with or without modification" as
* you see fit. Enjoy.
*
* Kevin Ruddy
* Powerdog Industries, Inc.
*/
/*
* Copyright (c) 1994 Powerdog Industries. 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 Powerdog Industries.
* 4. The name of Powerdog Industries may not be used to endorse or
* promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY POWERDOG INDUSTRIES ``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 POWERDOG INDUSTRIES 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.
*/
#include <sys/cdefs.h>
#ifndef lint
#ifndef NOID
static char copyright[] __unused =
"@(#) Copyright (c) 1994 Powerdog Industries. All rights reserved.";
static char sccsid[] __unused = "@(#)strptime.c 0.1 (Powerdog) 94/03/27";
#endif /* !defined NOID */
#endif /* not lint */
__FBSDID("$FreeBSD$");
#include "namespace.h"
#include <time.h>
#include <ctype.h>
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include "un-namespace.h"
#include "libc_private.h"
#include "timelocal.h"
static char * _strptime(const char *, const char *, struct tm *, int *);
#define asizeof(a) (sizeof (a) / sizeof ((a)[0]))
static char *
_strptime(const char *buf, const char *fmt, struct tm *tm, int *GMTp)
{
char c;
const char *ptr;
int i,
len;
int Ealternative, Oalternative;
struct lc_time_T *tptr = __get_current_time_locale();
ptr = fmt;
while (*ptr != 0) {
if (*buf == 0)
break;
c = *ptr++;
if (c != '%') {
if (isspace((unsigned char)c))
while (*buf != 0 && isspace((unsigned char)*buf))
buf++;
else if (c != *buf++)
return 0;
continue;
}
Ealternative = 0;
Oalternative = 0;
label:
c = *ptr++;
switch (c) {
case 0:
case '%':
if (*buf++ != '%')
return 0;
break;
case '+':
buf = _strptime(buf, tptr->date_fmt, tm, GMTp);
if (buf == 0)
return 0;
break;
case 'C':
if (!isdigit((unsigned char)*buf))
return 0;
/* XXX This will break for 3-digit centuries. */
len = 2;
for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
if (i < 19)
return 0;
tm->tm_year = i * 100 - 1900;
break;
case 'c':
buf = _strptime(buf, tptr->c_fmt, tm, GMTp);
if (buf == 0)
return 0;
break;
case 'D':
buf = _strptime(buf, "%m/%d/%y", tm, GMTp);
if (buf == 0)
return 0;
break;
case 'E':
if (Ealternative || Oalternative)
break;
Ealternative++;
goto label;
case 'O':
if (Ealternative || Oalternative)
break;
Oalternative++;
goto label;
case 'F':
buf = _strptime(buf, "%Y-%m-%d", tm, GMTp);
if (buf == 0)
return 0;
break;
case 'R':
buf = _strptime(buf, "%H:%M", tm, GMTp);
if (buf == 0)
return 0;
break;
case 'r':
buf = _strptime(buf, tptr->ampm_fmt, tm, GMTp);
if (buf == 0)
return 0;
break;
case 'T':
buf = _strptime(buf, "%H:%M:%S", tm, GMTp);
if (buf == 0)
return 0;
break;
case 'X':
buf = _strptime(buf, tptr->X_fmt, tm, GMTp);
if (buf == 0)
return 0;
break;
case 'x':
buf = _strptime(buf, tptr->x_fmt, tm, GMTp);
if (buf == 0)
return 0;
break;
case 'j':
if (!isdigit((unsigned char)*buf))
return 0;
len = 3;
for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
if (i < 1 || i > 366)
return 0;
tm->tm_yday = i - 1;
break;
case 'M':
case 'S':
if (*buf == 0 || isspace((unsigned char)*buf))
break;
if (!isdigit((unsigned char)*buf))
return 0;
len = 2;
for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
if (c == 'M') {
if (i > 59)
return 0;
tm->tm_min = i;
} else {
if (i > 60)
return 0;
tm->tm_sec = i;
}
if (*buf != 0 && isspace((unsigned char)*buf))
while (*ptr != 0 && !isspace((unsigned char)*ptr))
ptr++;
break;
case 'H':
case 'I':
case 'k':
case 'l':
/*
* Of these, %l is the only specifier explicitly
* documented as not being zero-padded. However,
* there is no harm in allowing zero-padding.
*
* XXX The %l specifier may gobble one too many
* digits if used incorrectly.
*/
if (!isdigit((unsigned char)*buf))
return 0;
len = 2;
for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
if (c == 'H' || c == 'k') {
if (i > 23)
return 0;
} else if (i > 12)
return 0;
tm->tm_hour = i;
if (*buf != 0 && isspace((unsigned char)*buf))
while (*ptr != 0 && !isspace((unsigned char)*ptr))
ptr++;
break;
case 'p':
/*
* XXX This is bogus if parsed before hour-related
* specifiers.
*/
len = strlen(tptr->am);
if (strncasecmp(buf, tptr->am, len) == 0) {
if (tm->tm_hour > 12)
return 0;
if (tm->tm_hour == 12)
tm->tm_hour = 0;
buf += len;
break;
}
len = strlen(tptr->pm);
if (strncasecmp(buf, tptr->pm, len) == 0) {
if (tm->tm_hour > 12)
return 0;
if (tm->tm_hour != 12)
tm->tm_hour += 12;
buf += len;
break;
}
return 0;
case 'A':
case 'a':
for (i = 0; i < asizeof(tptr->weekday); i++) {
len = strlen(tptr->weekday[i]);
if (strncasecmp(buf, tptr->weekday[i],
len) == 0)
break;
len = strlen(tptr->wday[i]);
if (strncasecmp(buf, tptr->wday[i],
len) == 0)
break;
}
if (i == asizeof(tptr->weekday))
return 0;
tm->tm_wday = i;
buf += len;
break;
case 'U':
case 'W':
/*
* XXX This is bogus, as we can not assume any valid
* information present in the tm structure at this
* point to calculate a real value, so just check the
* range for now.
*/
if (!isdigit((unsigned char)*buf))
return 0;
len = 2;
for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
if (i > 53)
return 0;
if (*buf != 0 && isspace((unsigned char)*buf))
while (*ptr != 0 && !isspace((unsigned char)*ptr))
ptr++;
break;
case 'w':
if (!isdigit((unsigned char)*buf))
return 0;
i = *buf - '0';
if (i > 6)
return 0;
tm->tm_wday = i;
if (*buf != 0 && isspace((unsigned char)*buf))
while (*ptr != 0 && !isspace((unsigned char)*ptr))
ptr++;
break;
case 'd':
case 'e':
/*
* The %e specifier is explicitly documented as not
* being zero-padded but there is no harm in allowing
* such padding.
*
* XXX The %e specifier may gobble one too many
* digits if used incorrectly.
*/
if (!isdigit((unsigned char)*buf))
return 0;
len = 2;
for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
if (i > 31)
return 0;
tm->tm_mday = i;
if (*buf != 0 && isspace((unsigned char)*buf))
while (*ptr != 0 && !isspace((unsigned char)*ptr))
ptr++;
break;
case 'B':
case 'b':
case 'h':
for (i = 0; i < asizeof(tptr->month); i++) {
if (Oalternative) {
if (c == 'B') {
len = strlen(tptr->alt_month[i]);
if (strncasecmp(buf,
tptr->alt_month[i],
len) == 0)
break;
}
} else {
len = strlen(tptr->month[i]);
if (strncasecmp(buf, tptr->month[i],
len) == 0)
break;
len = strlen(tptr->mon[i]);
if (strncasecmp(buf, tptr->mon[i],
len) == 0)
break;
}
}
if (i == asizeof(tptr->month))
return 0;
tm->tm_mon = i;
buf += len;
break;
case 'm':
if (!isdigit((unsigned char)*buf))
return 0;
len = 2;
for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
if (i < 1 || i > 12)
return 0;
tm->tm_mon = i - 1;
if (*buf != 0 && isspace((unsigned char)*buf))
while (*ptr != 0 && !isspace((unsigned char)*ptr))
ptr++;
break;
case 's':
{
char *cp;
time_t t;
t = strtol(buf, &cp, 10);
if (t == LONG_MAX)
return 0;
buf = cp;
gmtime_r(&t, tm);
*GMTp = 1;
}
break;
case 'Y':
case 'y':
if (*buf == 0 || isspace((unsigned char)*buf))
break;
if (!isdigit((unsigned char)*buf))
return 0;
len = (c == 'Y') ? 4 : 2;
for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
if (c == 'Y')
i -= 1900;
if (c == 'y' && i < 69)
i += 100;
if (i < 0)
return 0;
tm->tm_year = i;
if (*buf != 0 && isspace((unsigned char)*buf))
while (*ptr != 0 && !isspace((unsigned char)*ptr))
ptr++;
break;
case 'Z':
{
const char *cp;
char *zonestr;
for (cp = buf; *cp && isupper((unsigned char)*cp); ++cp) {/*empty*/}
if (cp - buf) {
zonestr = alloca(cp - buf + 1);
strncpy(zonestr, buf, cp - buf);
zonestr[cp - buf] = '\0';
tzset();
if (0 == strcmp(zonestr, "GMT")) {
*GMTp = 1;
} else if (0 == strcmp(zonestr, tzname[0])) {
tm->tm_isdst = 0;
} else if (0 == strcmp(zonestr, tzname[1])) {
tm->tm_isdst = 1;
} else {
return 0;
}
buf += cp - buf;
}
}
break;
}
}
return (char *)buf;
}
char *
strptime(const char * __restrict buf, const char * __restrict fmt,
struct tm * __restrict tm)
{
char *ret;
int gmt;
gmt = 0;
ret = _strptime(buf, fmt, tm, &gmt);
if (ret && gmt) {
time_t t = timegm(tm);
localtime_r(&t, tm);
}
return (ret);
}