--- /dev/null
+/* $NetBSD: strptime.c,v 1.28 2008/04/28 20:23:01 martin 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 1.28 2008/04/28 20:23:01 martin Exp $");
+#endif
+
+#include "namespace.h"
+#include <sys/localedef.h>
+#include <ctype.h>
+#include <locale.h>
+#include <string.h>
+#include <time.h>
+#include <tzfile.h>
+
+#ifdef __weak_alias
+__weak_alias(strptime,_strptime)
+#endif
+
+#define _ctloc(x) (_CurrentTimeLocale->x)
+
+/*
+ * 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 const char gmt[4] = { "GMT" };
+
+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)
+{
+ unsigned char c;
+ const unsigned char *bp;
+ int alt_format, i, split_year = 0;
+ 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 = _ctloc(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 =_ctloc(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 =_ctloc(t_fmt);
+ goto recurse;
+
+ case 'x': /* The date, using the locale's format. */
+ new_fmt =_ctloc(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, _ctloc(day),
+ _ctloc(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, _ctloc(mon),
+ _ctloc(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, _ctloc(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;
+
+ 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 '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 {
+ const unsigned char *ep;
+
+ 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;
+
+ /*
+ * 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;
+ unsigned int 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;
+}
