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diff --git a/libmisc/strtoday.c b/libmisc/strtoday.c
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+/*
+ * SPDX-FileCopyrightText: 1991 - 1994, Julianne Frances Haugh
+ * SPDX-FileCopyrightText: 1996 - 1999, Marek Michałkiewicz
+ * SPDX-FileCopyrightText: 2003 - 2005, Tomasz Kłoczko
+ * SPDX-FileCopyrightText: 2008 , Nicolas François
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#if !defined(__GLIBC__)
+#define _XOPEN_SOURCE 500
+#endif
+
+#include <config.h>
+
+#include <ctype.h>
+
+#ident "$Id$"
+
+#include "defines.h"
+#include "prototypes.h"
+
+#ifndef USE_GETDATE
+#define USE_GETDATE 1
+#endif
+
+#if USE_GETDATE
+#include "getdate.h"
+/*
+ * strtoday() now uses get_date() (borrowed from GNU shellutils)
+ * which can handle many date formats, for example:
+ * 1970-09-17 # ISO 8601.
+ * 70-9-17 # This century assumed by default.
+ * 70-09-17 # Leading zeros are ignored.
+ * 9/17/72 # Common U.S. writing.
+ * 24 September 1972
+ * 24 Sept 72 # September has a special abbreviation.
+ * 24 Sep 72 # Three-letter abbreviations always allowed.
+ * Sep 24, 1972
+ * 24-sep-72
+ * 24sep72
+ */
+long strtoday (const char *str)
+{
+ time_t t;
+ bool isnum = true;
+ const char *s = str;
+
+ /*
+ * get_date() interprets an empty string as the current date,
+ * which is not what we expect, unless you're a BOFH :-).
+ * (useradd sets sp_expire = current date for new lusers)
+ */
+ if ((NULL == str) || ('\0' == *str)) {
+ return -1;
+ }
+
+ /* If a numerical value is provided, this is already a number of
+ * days since EPOCH.
+ */
+ if ('-' == *s) {
+ s++;
+ }
+ while (' ' == *s) {
+ s++;
+ }
+ while (isnum && ('\0' != *s)) {
+ if (!isdigit (*s)) {
+ isnum = false;
+ }
+ s++;
+ }
+ if (isnum) {
+ long retdate;
+ if (getlong (str, &retdate) == 0) {
+ return -2;
+ }
+ return retdate;
+ }
+
+ t = get_date (str, NULL);
+ if ((time_t) - 1 == t) {
+ return -2;
+ }
+ /* convert seconds to days since 1970-01-01 */
+ return (long) (t + DAY / 2) / DAY;
+}
+
+#else /* !USE_GETDATE */
+/*
+ * Old code, just in case get_date() doesn't work as expected...
+ */
+#include <stdio.h>
+#ifdef HAVE_STRPTIME
+/*
+ * for now we allow just one format, but we can define more later
+ * (we try them all until one succeeds). --marekm
+ */
+static const char *const date_formats[] = {
+ "%Y-%m-%d",
+ (char *) 0
+};
+#else
+/*
+ * days and juldays are used to compute the number of days in the
+ * current month, and the cumulative number of days in the preceding
+ * months. they are declared so that january is 1, not 0.
+ */
+static const short days[13] = { 0,
+ 31, 28, 31, 30, 31, 30, /* JAN - JUN */
+ 31, 31, 30, 31, 30, 31
+}; /* JUL - DEC */
+
+static const short juldays[13] = { 0,
+ 0, 31, 59, 90, 120, 151, /* JAN - JUN */
+ 181, 212, 243, 273, 304, 334
+}; /* JUL - DEC */
+#endif
+
+/*
+ * strtoday - compute the number of days since 1970.
+ *
+ * the total number of days prior to the current date is
+ * computed. january 1, 1970 is used as the origin with
+ * it having a day number of 0.
+ */
+
+long strtoday (const char *str)
+{
+#ifdef HAVE_STRPTIME
+ struct tm tp;
+ const char *const *fmt;
+ char *cp;
+ time_t result;
+
+ memzero (&tp, sizeof tp);
+ for (fmt = date_formats; *fmt; fmt++) {
+ cp = strptime ((char *) str, *fmt, &tp);
+ if ((NULL == cp) || ('\0' != *cp)) {
+ continue;
+ }
+
+ result = mktime (&tp);
+ if ((time_t) - 1 == result) {
+ continue;
+ }
+
+ return (long) (result / DAY); /* success */
+ }
+ return -1;
+#else
+ char slop[2];
+ int month;
+ int day;
+ int year;
+ long total;
+
+ /*
+ * start by separating the month, day and year. the order
+ * is compiled in ...
+ */
+
+ if (sscanf (str, "%d/%d/%d%c", &year, &month, &day, slop) != 3) {
+ return -1;
+ }
+
+ /*
+ * the month, day of the month, and year are checked for
+ * correctness and the year adjusted so it falls between
+ * 1970 and 2069.
+ */
+
+ if ((month < 1) || (month > 12)) {
+ return -1;
+ }
+
+ if (day < 1) {
+ return -1;
+ }
+
+ if ( ((2 != month) || ((year % 4) != 0))
+ && (day > days[month])) {
+ return -1;
+ } else if ((month == 2) && ((year % 4) == 0) && (day > 29)) {
+ return -1;
+ }
+
+ if (year < 0) {
+ return -1;
+ } else if (year <= 69) {
+ year += 2000;
+ } else if (year <= 99) {
+ year += 1900;
+ }
+
+ /*
+ * On systems with 32-bit signed time_t, time wraps around in 2038
+ * - for now we just limit the year to 2037 (instead of 2069).
+ * This limit can be removed once no one is using 32-bit systems
+ * anymore :-). --marekm
+ */
+ if ((year < 1970) || (year > 2037)) {
+ return -1;
+ }
+
+ /*
+ * the total number of days is the total number of days in all
+ * the whole years, plus the number of leap days, plus the
+ * number of days in the whole months preceding, plus the number
+ * of days so far in the month.
+ */
+
+ total = (long) ((year - 1970) * 365L) + (((year + 1) - 1970) / 4);
+ total += (long) juldays[month] + (month > 2 && (year % 4) == 0 ? 1 : 0);
+ total += (long) day - 1;
+
+ return total;
+#endif /* HAVE_STRPTIME */
+}
+#endif /* !USE_GETDATE */