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mirror of https://git.FreeBSD.org/src.git synced 2024-12-27 11:55:06 +00:00
freebsd/lib/libc/stdtime/strptime.c
Jacques Vidrine c91e947dbd Detect range errors when using the %s specifier. Previously, LONG_MAX
was rejected as a range error, while any values less than LONG_MIN
were silently substituted with LONG_MIN.  Furthermore, on some
platforms `time_t' has less range than `long' (e.g. alpha), which may
give incorrect results when parsing some strings.
2003-11-17 04:19:15 +00:00

539 lines
12 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 <errno.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;
int sverrno;
long n;
time_t t;
sverrno = errno;
errno = 0;
n = strtol(buf, &cp, 10);
if (errno == ERANGE || (long)(t = n) != n) {
errno = sverrno;
return 0;
}
errno = sverrno;
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);
}