freebsd-src/lib/libc/stdtime/strptime.c
Warner Losh 0b8224d1cc Remove copyright strings ifdef'd out
We've ifdef'd out the copyright strings for some time now. Go ahead and
remove the ifdefs. Plus whatever other detritis was left over from other
recent removals. These copyright strings are present in the comments and
are largely from CSRG's attempt at adding their copyright to every
binary file (which modern interpretations of the license doesn't
require).

Sponsored by:		Netflix
2023-11-26 22:23:58 -07:00

716 lines
15 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2014 Gary Mills
* Copyright 2011, Nexenta Systems, Inc. All rights reserved.
* Copyright (c) 1994 Powerdog Industries. All rights reserved.
*
* Copyright (c) 2011 The FreeBSD Foundation
*
* Portions of this software were developed by David Chisnall
* under sponsorship from the FreeBSD Foundation.
*
* 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.
*
* 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.
*
* The views and conclusions contained in the software and documentation
* are those of the authors and should not be interpreted as representing
* official policies, either expressed or implied, of Powerdog Industries.
*/
#include "namespace.h"
#include <time.h>
#include <ctype.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include "private.h"
#include "un-namespace.h"
#include "libc_private.h"
#include "timelocal.h"
#include "tzfile.h"
static char * _strptime(const char *, const char *, struct tm *, int *, locale_t);
#define asizeof(a) (sizeof(a) / sizeof((a)[0]))
#define FLAG_NONE (1 << 0)
#define FLAG_YEAR (1 << 1)
#define FLAG_MONTH (1 << 2)
#define FLAG_YDAY (1 << 3)
#define FLAG_MDAY (1 << 4)
#define FLAG_WDAY (1 << 5)
/*
* Calculate the week day of the first day of a year. Valid for
* the Gregorian calendar, which began Sept 14, 1752 in the UK
* and its colonies. Ref:
* http://en.wikipedia.org/wiki/Determination_of_the_day_of_the_week
*/
static int
first_wday_of(int year)
{
return (((2 * (3 - (year / 100) % 4)) + (year % 100) +
((year % 100) / 4) + (isleap(year) ? 6 : 0) + 1) % 7);
}
static char *
_strptime(const char *buf, const char *fmt, struct tm *tm, int *GMTp,
locale_t locale)
{
char c;
const char *ptr;
int day_offset = -1, wday_offset;
int week_offset;
int i, len;
int flags;
int Ealternative, Oalternative;
int century, year;
const struct lc_time_T *tptr = __get_current_time_locale(locale);
static int start_of_month[2][13] = {
{0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365},
{0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366}
};
flags = FLAG_NONE;
century = -1;
year = -1;
ptr = fmt;
while (*ptr != 0) {
c = *ptr++;
if (c != '%') {
if (isspace_l((unsigned char)c, locale))
while (*buf != 0 &&
isspace_l((unsigned char)*buf, locale))
buf++;
else if (c != *buf++)
return (NULL);
continue;
}
Ealternative = 0;
Oalternative = 0;
label:
c = *ptr++;
switch (c) {
case '%':
if (*buf++ != '%')
return (NULL);
break;
case '+':
buf = _strptime(buf, tptr->date_fmt, tm, GMTp, locale);
if (buf == NULL)
return (NULL);
flags |= FLAG_WDAY | FLAG_MONTH | FLAG_MDAY | FLAG_YEAR;
break;
case 'C':
if (!isdigit_l((unsigned char)*buf, locale))
return (NULL);
/* XXX This will break for 3-digit centuries. */
len = 2;
for (i = 0; len && *buf != 0 &&
isdigit_l((unsigned char)*buf, locale); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
century = i;
flags |= FLAG_YEAR;
break;
case 'c':
buf = _strptime(buf, tptr->c_fmt, tm, GMTp, locale);
if (buf == NULL)
return (NULL);
flags |= FLAG_WDAY | FLAG_MONTH | FLAG_MDAY | FLAG_YEAR;
break;
case 'D':
buf = _strptime(buf, "%m/%d/%y", tm, GMTp, locale);
if (buf == NULL)
return (NULL);
flags |= FLAG_MONTH | FLAG_MDAY | FLAG_YEAR;
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, locale);
if (buf == NULL)
return (NULL);
flags |= FLAG_MONTH | FLAG_MDAY | FLAG_YEAR;
break;
case 'R':
buf = _strptime(buf, "%H:%M", tm, GMTp, locale);
if (buf == NULL)
return (NULL);
break;
case 'r':
buf = _strptime(buf, tptr->ampm_fmt, tm, GMTp, locale);
if (buf == NULL)
return (NULL);
break;
case 'T':
buf = _strptime(buf, "%H:%M:%S", tm, GMTp, locale);
if (buf == NULL)
return (NULL);
break;
case 'X':
buf = _strptime(buf, tptr->X_fmt, tm, GMTp, locale);
if (buf == NULL)
return (NULL);
break;
case 'x':
buf = _strptime(buf, tptr->x_fmt, tm, GMTp, locale);
if (buf == NULL)
return (NULL);
flags |= FLAG_MONTH | FLAG_MDAY | FLAG_YEAR;
break;
case 'j':
if (!isdigit_l((unsigned char)*buf, locale))
return (NULL);
len = 3;
for (i = 0; len && *buf != 0 &&
isdigit_l((unsigned char)*buf, locale); buf++){
i *= 10;
i += *buf - '0';
len--;
}
if (i < 1 || i > 366)
return (NULL);
tm->tm_yday = i - 1;
flags |= FLAG_YDAY;
break;
case 'M':
case 'S':
if (*buf == 0 ||
isspace_l((unsigned char)*buf, locale))
break;
if (!isdigit_l((unsigned char)*buf, locale))
return (NULL);
len = 2;
for (i = 0; len && *buf != 0 &&
isdigit_l((unsigned char)*buf, locale); buf++){
i *= 10;
i += *buf - '0';
len--;
}
if (c == 'M') {
if (i > 59)
return (NULL);
tm->tm_min = i;
} else {
if (i > 60)
return (NULL);
tm->tm_sec = i;
}
break;
case 'H':
case 'I':
case 'k':
case 'l':
/*
* %k and %l specifiers are documented as being
* blank-padded. However, there is no harm in
* allowing zero-padding.
*
* XXX %k and %l specifiers may gobble one too many
* digits if used incorrectly.
*/
len = 2;
if ((c == 'k' || c == 'l') &&
isblank_l((unsigned char)*buf, locale)) {
buf++;
len = 1;
}
if (!isdigit_l((unsigned char)*buf, locale))
return (NULL);
for (i = 0; len && *buf != 0 &&
isdigit_l((unsigned char)*buf, locale); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
if (c == 'H' || c == 'k') {
if (i > 23)
return (NULL);
} else if (i == 0 || i > 12)
return (NULL);
tm->tm_hour = i;
break;
case 'p':
/*
* XXX This is bogus if parsed before hour-related
* specifiers.
*/
if (tm->tm_hour > 12)
return (NULL);
len = strlen(tptr->am);
if (strncasecmp_l(buf, tptr->am, len, locale) == 0) {
if (tm->tm_hour == 12)
tm->tm_hour = 0;
buf += len;
break;
}
len = strlen(tptr->pm);
if (strncasecmp_l(buf, tptr->pm, len, locale) == 0) {
if (tm->tm_hour != 12)
tm->tm_hour += 12;
buf += len;
break;
}
return (NULL);
case 'A':
case 'a':
for (i = 0; i < asizeof(tptr->weekday); i++) {
len = strlen(tptr->weekday[i]);
if (strncasecmp_l(buf, tptr->weekday[i],
len, locale) == 0)
break;
len = strlen(tptr->wday[i]);
if (strncasecmp_l(buf, tptr->wday[i],
len, locale) == 0)
break;
}
if (i == asizeof(tptr->weekday))
return (NULL);
buf += len;
tm->tm_wday = i;
flags |= FLAG_WDAY;
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_l((unsigned char)*buf, locale))
return (NULL);
len = 2;
for (i = 0; len && *buf != 0 &&
isdigit_l((unsigned char)*buf, locale); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
if (i > 53)
return (NULL);
if (c == 'U')
day_offset = TM_SUNDAY;
else
day_offset = TM_MONDAY;
week_offset = i;
break;
case 'u':
case 'w':
if (!isdigit_l((unsigned char)*buf, locale))
return (NULL);
i = *buf++ - '0';
if (i < 0 || i > 7 || (c == 'u' && i < 1) ||
(c == 'w' && i > 6))
return (NULL);
tm->tm_wday = i % 7;
flags |= FLAG_WDAY;
break;
case 'e':
/*
* With %e format, our strftime(3) adds a blank space
* before single digits.
*/
if (*buf != 0 &&
isspace_l((unsigned char)*buf, locale))
buf++;
/* FALLTHROUGH */
case 'd':
/*
* The %e specifier was once explicitly documented as
* not being zero-padded but was later changed to
* equivalent to %d. There is no harm in allowing
* such padding.
*
* XXX The %e specifier may gobble one too many
* digits if used incorrectly.
*/
if (!isdigit_l((unsigned char)*buf, locale))
return (NULL);
len = 2;
for (i = 0; len && *buf != 0 &&
isdigit_l((unsigned char)*buf, locale); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
if (i == 0 || i > 31)
return (NULL);
tm->tm_mday = i;
flags |= FLAG_MDAY;
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_l(buf,
tptr->alt_month[i],
len, locale) == 0)
break;
}
} else {
len = strlen(tptr->month[i]);
if (strncasecmp_l(buf, tptr->month[i],
len, locale) == 0)
break;
}
}
/*
* Try the abbreviated month name if the full name
* wasn't found and Oalternative was not requested.
*/
if (i == asizeof(tptr->month) && !Oalternative) {
for (i = 0; i < asizeof(tptr->month); i++) {
len = strlen(tptr->mon[i]);
if (strncasecmp_l(buf, tptr->mon[i],
len, locale) == 0)
break;
}
}
if (i == asizeof(tptr->month))
return (NULL);
tm->tm_mon = i;
buf += len;
flags |= FLAG_MONTH;
break;
case 'm':
if (!isdigit_l((unsigned char)*buf, locale))
return (NULL);
len = 2;
for (i = 0; len && *buf != 0 &&
isdigit_l((unsigned char)*buf, locale); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
if (i < 1 || i > 12)
return (NULL);
tm->tm_mon = i - 1;
flags |= FLAG_MONTH;
break;
case 's':
{
char *cp;
int sverrno;
long n;
time_t t;
sverrno = errno;
errno = 0;
n = strtol_l(buf, &cp, 10, locale);
if (errno == ERANGE || (long)(t = n) != n) {
errno = sverrno;
return (NULL);
}
errno = sverrno;
buf = cp;
if (gmtime_r(&t, tm) == NULL)
return (NULL);
*GMTp = 1;
flags |= FLAG_YDAY | FLAG_WDAY | FLAG_MONTH |
FLAG_MDAY | FLAG_YEAR;
}
break;
case 'Y':
case 'y':
if (*buf == 0 ||
isspace_l((unsigned char)*buf, locale))
break;
if (!isdigit_l((unsigned char)*buf, locale))
return (NULL);
len = (c == 'Y') ? 4 : 2;
for (i = 0; len && *buf != 0 &&
isdigit_l((unsigned char)*buf, locale); buf++) {
i *= 10;
i += *buf - '0';
len--;
}
if (c == 'Y')
century = i / 100;
year = i % 100;
flags |= FLAG_YEAR;
break;
case 'Z':
{
const char *cp;
char *zonestr;
for (cp = buf; *cp &&
isupper_l((unsigned char)*cp, locale); ++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") ||
0 == strcmp(zonestr, "UTC")) {
*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 (NULL);
}
buf += cp - buf;
}
}
break;
case 'z':
{
int sign = 1;
if (*buf != '+') {
if (*buf == '-')
sign = -1;
else
return (NULL);
}
buf++;
i = 0;
for (len = 4; len > 0; len--) {
if (isdigit_l((unsigned char)*buf, locale)) {
i *= 10;
i += *buf - '0';
buf++;
} else if (len == 2) {
i *= 100;
break;
} else
return (NULL);
}
if (i > 1400 || (sign == -1 && i > 1200) ||
(i % 100) >= 60)
return (NULL);
tm->tm_hour -= sign * (i / 100);
tm->tm_min -= sign * (i % 100);
*GMTp = 1;
}
break;
case 'n':
case 't':
while (isspace_l((unsigned char)*buf, locale))
buf++;
break;
default:
return (NULL);
}
}
if (century != -1 || year != -1) {
if (year == -1)
year = 0;
if (century == -1) {
if (year < 69)
year += 100;
} else
year += century * 100 - TM_YEAR_BASE;
tm->tm_year = year;
}
if (!(flags & FLAG_YDAY) && (flags & FLAG_YEAR)) {
if ((flags & (FLAG_MONTH | FLAG_MDAY)) ==
(FLAG_MONTH | FLAG_MDAY)) {
tm->tm_yday = start_of_month[isleap(tm->tm_year +
TM_YEAR_BASE)][tm->tm_mon] + (tm->tm_mday - 1);
flags |= FLAG_YDAY;
} else if (day_offset != -1) {
int tmpwday, tmpyday, fwo;
fwo = first_wday_of(tm->tm_year + TM_YEAR_BASE);
/* No incomplete week (week 0). */
if (week_offset == 0 && fwo == day_offset)
return (NULL);
/* Set the date to the first Sunday (or Monday)
* of the specified week of the year.
*/
tmpwday = (flags & FLAG_WDAY) ? tm->tm_wday :
day_offset;
tmpyday = (7 - fwo + day_offset) % 7 +
(week_offset - 1) * 7 +
(tmpwday - day_offset + 7) % 7;
/* Impossible yday for incomplete week (week 0). */
if (tmpyday < 0) {
if (flags & FLAG_WDAY)
return (NULL);
tmpyday = 0;
}
tm->tm_yday = tmpyday;
flags |= FLAG_YDAY;
}
}
if ((flags & (FLAG_YEAR | FLAG_YDAY)) == (FLAG_YEAR | FLAG_YDAY)) {
if (!(flags & FLAG_MONTH)) {
i = 0;
while (tm->tm_yday >=
start_of_month[isleap(tm->tm_year +
TM_YEAR_BASE)][i])
i++;
if (i > 12) {
i = 1;
tm->tm_yday -=
start_of_month[isleap(tm->tm_year +
TM_YEAR_BASE)][12];
tm->tm_year++;
}
tm->tm_mon = i - 1;
flags |= FLAG_MONTH;
}
if (!(flags & FLAG_MDAY)) {
tm->tm_mday = tm->tm_yday -
start_of_month[isleap(tm->tm_year + TM_YEAR_BASE)]
[tm->tm_mon] + 1;
flags |= FLAG_MDAY;
}
if (!(flags & FLAG_WDAY)) {
i = 0;
wday_offset = first_wday_of(tm->tm_year);
while (i++ <= tm->tm_yday) {
if (wday_offset++ >= 6)
wday_offset = 0;
}
tm->tm_wday = wday_offset;
flags |= FLAG_WDAY;
}
}
return ((char *)buf);
}
char *
strptime_l(const char * __restrict buf, const char * __restrict fmt,
struct tm * __restrict tm, locale_t loc)
{
char *ret;
int gmt;
FIX_LOCALE(loc);
gmt = 0;
ret = _strptime(buf, fmt, tm, &gmt, loc);
if (ret && gmt) {
time_t t = timegm(tm);
localtime_r(&t, tm);
}
return (ret);
}
char *
strptime(const char * __restrict buf, const char * __restrict fmt,
struct tm * __restrict tm)
{
return strptime_l(buf, fmt, tm, __get_locale());
}