minix/lib/libc/time/strptime.c

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/* $NetBSD: strptime.c,v 1.38 2013/05/17 12:55:57 joerg Exp $ */
/*-
* Copyright (c) 1997, 1998, 2005, 2008 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code was contributed to The NetBSD Foundation by Klaus Klein.
* Heavily optimised by David Laight
*
* 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 THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: strptime.c,v 1.38 2013/05/17 12:55:57 joerg Exp $");
#endif
#include "namespace.h"
#include <sys/localedef.h>
#include <ctype.h>
#include <locale.h>
#include <string.h>
#include <time.h>
#include <tzfile.h>
#include "private.h"
#include "setlocale_local.h"
#ifdef __weak_alias
__weak_alias(strptime,_strptime)
__weak_alias(strptime_l, _strptime_l)
#endif
#define _TIME_LOCALE(loc) \
((_TimeLocale *)((loc)->part_impl[(size_t)LC_TIME]))
/*
* We do not implement alternate representations. However, we always
* check whether a given modifier is allowed for a certain conversion.
*/
#define ALT_E 0x01
#define ALT_O 0x02
#define LEGAL_ALT(x) { if (alt_format & ~(x)) return NULL; }
static char gmt[] = { "GMT" };
static char utc[] = { "UTC" };
/* RFC-822/RFC-2822 */
static const char * const nast[5] = {
"EST", "CST", "MST", "PST", "\0\0\0"
};
static const char * const nadt[5] = {
"EDT", "CDT", "MDT", "PDT", "\0\0\0"
};
static const u_char *conv_num(const unsigned char *, int *, uint, uint);
static const u_char *find_string(const u_char *, int *, const char * const *,
const char * const *, int);
char *
strptime(const char *buf, const char *fmt, struct tm *tm)
{
return strptime_l(buf, fmt, tm, _current_locale());
}
char *
strptime_l(const char *buf, const char *fmt, struct tm *tm, locale_t loc)
{
unsigned char c;
const unsigned char *bp, *ep;
int alt_format, i, split_year = 0, neg = 0, offs;
const char *new_fmt;
bp = (const u_char *)buf;
while (bp != NULL && (c = *fmt++) != '\0') {
/* Clear `alternate' modifier prior to new conversion. */
alt_format = 0;
i = 0;
/* Eat up white-space. */
if (isspace(c)) {
while (isspace(*bp))
bp++;
continue;
}
if (c != '%')
goto literal;
again: switch (c = *fmt++) {
case '%': /* "%%" is converted to "%". */
literal:
if (c != *bp++)
return NULL;
LEGAL_ALT(0);
continue;
/*
* "Alternative" modifiers. Just set the appropriate flag
* and start over again.
*/
case 'E': /* "%E?" alternative conversion modifier. */
LEGAL_ALT(0);
alt_format |= ALT_E;
goto again;
case 'O': /* "%O?" alternative conversion modifier. */
LEGAL_ALT(0);
alt_format |= ALT_O;
goto again;
/*
* "Complex" conversion rules, implemented through recursion.
*/
case 'c': /* Date and time, using the locale's format. */
new_fmt = _TIME_LOCALE(loc)->d_t_fmt;
goto recurse;
case 'D': /* The date as "%m/%d/%y". */
new_fmt = "%m/%d/%y";
LEGAL_ALT(0);
goto recurse;
case 'F': /* The date as "%Y-%m-%d". */
new_fmt = "%Y-%m-%d";
LEGAL_ALT(0);
goto recurse;
case 'R': /* The time as "%H:%M". */
new_fmt = "%H:%M";
LEGAL_ALT(0);
goto recurse;
case 'r': /* The time in 12-hour clock representation. */
new_fmt = _TIME_LOCALE(loc)->t_fmt_ampm;
LEGAL_ALT(0);
goto recurse;
case 'T': /* The time as "%H:%M:%S". */
new_fmt = "%H:%M:%S";
LEGAL_ALT(0);
goto recurse;
case 'X': /* The time, using the locale's format. */
new_fmt = _TIME_LOCALE(loc)->t_fmt;
goto recurse;
case 'x': /* The date, using the locale's format. */
new_fmt = _TIME_LOCALE(loc)->d_fmt;
recurse:
bp = (const u_char *)strptime((const char *)bp,
new_fmt, tm);
LEGAL_ALT(ALT_E);
continue;
/*
* "Elementary" conversion rules.
*/
case 'A': /* The day of week, using the locale's form. */
case 'a':
bp = find_string(bp, &tm->tm_wday,
_TIME_LOCALE(loc)->day, _TIME_LOCALE(loc)->abday, 7);
LEGAL_ALT(0);
continue;
case 'B': /* The month, using the locale's form. */
case 'b':
case 'h':
bp = find_string(bp, &tm->tm_mon,
_TIME_LOCALE(loc)->mon, _TIME_LOCALE(loc)->abmon,
12);
LEGAL_ALT(0);
continue;
case 'C': /* The century number. */
i = 20;
bp = conv_num(bp, &i, 0, 99);
i = i * 100 - TM_YEAR_BASE;
if (split_year)
i += tm->tm_year % 100;
split_year = 1;
tm->tm_year = i;
LEGAL_ALT(ALT_E);
continue;
case 'd': /* The day of month. */
case 'e':
bp = conv_num(bp, &tm->tm_mday, 1, 31);
LEGAL_ALT(ALT_O);
continue;
case 'k': /* The hour (24-hour clock representation). */
LEGAL_ALT(0);
/* FALLTHROUGH */
case 'H':
bp = conv_num(bp, &tm->tm_hour, 0, 23);
LEGAL_ALT(ALT_O);
continue;
case 'l': /* The hour (12-hour clock representation). */
LEGAL_ALT(0);
/* FALLTHROUGH */
case 'I':
bp = conv_num(bp, &tm->tm_hour, 1, 12);
if (tm->tm_hour == 12)
tm->tm_hour = 0;
LEGAL_ALT(ALT_O);
continue;
case 'j': /* The day of year. */
i = 1;
bp = conv_num(bp, &i, 1, 366);
tm->tm_yday = i - 1;
LEGAL_ALT(0);
continue;
case 'M': /* The minute. */
bp = conv_num(bp, &tm->tm_min, 0, 59);
LEGAL_ALT(ALT_O);
continue;
case 'm': /* The month. */
i = 1;
bp = conv_num(bp, &i, 1, 12);
tm->tm_mon = i - 1;
LEGAL_ALT(ALT_O);
continue;
case 'p': /* The locale's equivalent of AM/PM. */
bp = find_string(bp, &i, _TIME_LOCALE(loc)->am_pm,
NULL, 2);
if (tm->tm_hour > 11)
return NULL;
tm->tm_hour += i * 12;
LEGAL_ALT(0);
continue;
case 'S': /* The seconds. */
bp = conv_num(bp, &tm->tm_sec, 0, 61);
LEGAL_ALT(ALT_O);
continue;
#ifndef TIME_MAX
#define TIME_MAX INT64_MAX
#endif
case 's': /* seconds since the epoch */
{
time_t sse = 0;
uint64_t rulim = TIME_MAX;
if (*bp < '0' || *bp > '9') {
bp = NULL;
continue;
}
do {
sse *= 10;
sse += *bp++ - '0';
rulim /= 10;
} while ((sse * 10 <= TIME_MAX) &&
rulim && *bp >= '0' && *bp <= '9');
if (sse < 0 || (uint64_t)sse > TIME_MAX) {
bp = NULL;
continue;
}
if (localtime_r(&sse, tm) == NULL)
bp = NULL;
}
continue;
case 'U': /* The week of year, beginning on sunday. */
case 'W': /* The week of year, beginning on monday. */
/*
* 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.
*/
bp = conv_num(bp, &i, 0, 53);
LEGAL_ALT(ALT_O);
continue;
case 'w': /* The day of week, beginning on sunday. */
bp = conv_num(bp, &tm->tm_wday, 0, 6);
LEGAL_ALT(ALT_O);
continue;
case 'u': /* The day of week, monday = 1. */
bp = conv_num(bp, &i, 1, 7);
tm->tm_wday = i % 7;
LEGAL_ALT(ALT_O);
continue;
case 'g': /* The year corresponding to the ISO week
* number but without the century.
*/
bp = conv_num(bp, &i, 0, 99);
continue;
case 'G': /* The year corresponding to the ISO week
* number with century.
*/
do
bp++;
while (isdigit(*bp));
continue;
case 'V': /* The ISO 8601:1988 week number as decimal */
bp = conv_num(bp, &i, 0, 53);
continue;
case 'Y': /* The year. */
i = TM_YEAR_BASE; /* just for data sanity... */
bp = conv_num(bp, &i, 0, 9999);
tm->tm_year = i - TM_YEAR_BASE;
LEGAL_ALT(ALT_E);
continue;
case 'y': /* The year within 100 years of the epoch. */
/* LEGAL_ALT(ALT_E | ALT_O); */
bp = conv_num(bp, &i, 0, 99);
if (split_year)
/* preserve century */
i += (tm->tm_year / 100) * 100;
else {
split_year = 1;
if (i <= 68)
i = i + 2000 - TM_YEAR_BASE;
else
i = i + 1900 - TM_YEAR_BASE;
}
tm->tm_year = i;
continue;
case 'Z':
tzset();
if (strncmp((const char *)bp, gmt, 3) == 0) {
tm->tm_isdst = 0;
#ifdef TM_GMTOFF
tm->TM_GMTOFF = 0;
#endif
#ifdef TM_ZONE
tm->TM_ZONE = gmt;
#endif
bp += 3;
} else {
ep = find_string(bp, &i,
(const char * const *)tzname,
NULL, 2);
if (ep != NULL) {
tm->tm_isdst = i;
#ifdef TM_GMTOFF
tm->TM_GMTOFF = -(timezone);
#endif
#ifdef TM_ZONE
tm->TM_ZONE = tzname[i];
#endif
}
bp = ep;
}
continue;
case 'z':
/*
* We recognize all ISO 8601 formats:
* Z = Zulu time/UTC
* [+-]hhmm
* [+-]hh:mm
* [+-]hh
* We recognize all RFC-822/RFC-2822 formats:
* UT|GMT
* North American : UTC offsets
* E[DS]T = Eastern : -4 | -5
* C[DS]T = Central : -5 | -6
* M[DS]T = Mountain: -6 | -7
* P[DS]T = Pacific : -7 | -8
* Military
* [A-IL-M] = -1 ... -9 (J not used)
* [N-Y] = +1 ... +12
*/
while (isspace(*bp))
bp++;
switch (*bp++) {
case 'G':
if (*bp++ != 'M')
return NULL;
/*FALLTHROUGH*/
case 'U':
if (*bp++ != 'T')
return NULL;
/*FALLTHROUGH*/
case 'Z':
tm->tm_isdst = 0;
#ifdef TM_GMTOFF
tm->TM_GMTOFF = 0;
#endif
#ifdef TM_ZONE
tm->TM_ZONE = utc;
#endif
continue;
case '+':
neg = 0;
break;
case '-':
neg = 1;
break;
default:
--bp;
ep = find_string(bp, &i, nast, NULL, 4);
if (ep != NULL) {
#ifdef TM_GMTOFF
tm->TM_GMTOFF = -5 - i;
#endif
#ifdef TM_ZONE
tm->TM_ZONE = __UNCONST(nast[i]);
#endif
bp = ep;
continue;
}
ep = find_string(bp, &i, nadt, NULL, 4);
if (ep != NULL) {
tm->tm_isdst = 1;
#ifdef TM_GMTOFF
tm->TM_GMTOFF = -4 - i;
#endif
#ifdef TM_ZONE
tm->TM_ZONE = __UNCONST(nadt[i]);
#endif
bp = ep;
continue;
}
if ((*bp >= 'A' && *bp <= 'I') ||
(*bp >= 'L' && *bp <= 'Y')) {
#ifdef TM_GMTOFF
/* Argh! No 'J'! */
if (*bp >= 'A' && *bp <= 'I')
tm->TM_GMTOFF =
('A' - 1) - (int)*bp;
else if (*bp >= 'L' && *bp <= 'M')
tm->TM_GMTOFF = 'A' - (int)*bp;
else if (*bp >= 'N' && *bp <= 'Y')
tm->TM_GMTOFF = (int)*bp - 'M';
#endif
#ifdef TM_ZONE
tm->TM_ZONE = NULL; /* XXX */
#endif
bp++;
continue;
}
return NULL;
}
offs = 0;
for (i = 0; i < 4; ) {
if (isdigit(*bp)) {
offs = offs * 10 + (*bp++ - '0');
i++;
continue;
}
if (i == 2 && *bp == ':') {
bp++;
continue;
}
break;
}
switch (i) {
case 2:
offs *= 100;
break;
case 4:
i = offs % 100;
if (i >= 60)
return NULL;
/* Convert minutes into decimal */
offs = (offs / 100) * 100 + (i * 50) / 30;
break;
default:
return NULL;
}
if (neg)
offs = -offs;
tm->tm_isdst = 0; /* XXX */
#ifdef TM_GMTOFF
tm->TM_GMTOFF = offs;
#endif
#ifdef TM_ZONE
tm->TM_ZONE = NULL; /* XXX */
#endif
continue;
/*
* Miscellaneous conversions.
*/
case 'n': /* Any kind of white-space. */
case 't':
while (isspace(*bp))
bp++;
LEGAL_ALT(0);
continue;
default: /* Unknown/unsupported conversion. */
return NULL;
}
}
return __UNCONST(bp);
}
static const u_char *
conv_num(const unsigned char *buf, int *dest, uint llim, uint ulim)
{
uint result = 0;
unsigned char ch;
/* The limit also determines the number of valid digits. */
uint rulim = ulim;
ch = *buf;
if (ch < '0' || ch > '9')
return NULL;
do {
result *= 10;
result += ch - '0';
rulim /= 10;
ch = *++buf;
} while ((result * 10 <= ulim) && rulim && ch >= '0' && ch <= '9');
if (result < llim || result > ulim)
return NULL;
*dest = result;
return buf;
}
static const u_char *
find_string(const u_char *bp, int *tgt, const char * const *n1,
const char * const *n2, int c)
{
int i;
size_t len;
/* check full name - then abbreviated ones */
for (; n1 != NULL; n1 = n2, n2 = NULL) {
for (i = 0; i < c; i++, n1++) {
len = strlen(*n1);
if (strncasecmp(*n1, (const char *)bp, len) == 0) {
*tgt = i;
return bp + len;
}
}
}
/* Nothing matched */
return NULL;
}