X-Git-Url: https://git.cworth.org/git?p=notmuch;a=blobdiff_plain;f=compat%2Ftimegm.c;fp=compat%2Ftimegm.c;h=3560c370f40c425ecf379fc3b9a9850355a515dc;hp=0000000000000000000000000000000000000000;hb=8c6b2e7e9d30bb3a9ef4fd8632cbf6d8d0673bb7;hpb=43843745dcbf31e96f447410e335a8d2aa21b00d

diff --git a/compat/timegm.c b/compat/timegm.c
new file mode 100644
index 00000000..3560c370
--- /dev/null
+++ b/compat/timegm.c
@@ -0,0 +1,56 @@
+/* timegm.c --- Implementation of replacement timegm function.
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 3, or (at
+   your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+   02110-1301, USA.  */
+
+/* Copyright 2013 Blake Jones. */
+
+#include <time.h>
+#include "compat.h"
+
+static int
+leapyear (int year)
+{
+    return ((year % 4) == 0 && ((year % 100) != 0 || (year % 400) == 0));
+}
+
+/*
+ * This is a simple implementation of timegm() which does what is needed
+ * by create_output() -- just turns the "struct tm" into a GMT time_t.
+ * It does not normalize any of the fields of the "struct tm", nor does
+ * it set tm_wday or tm_yday.
+ */
+time_t
+timegm (struct tm *tm)
+{
+    int	monthlen[2][12] = {
+	{ 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
+	{ 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
+    };
+    int	year, month, days;
+
+    days = 365 * (tm->tm_year - 70);
+    for (year = 70; year < tm->tm_year; year++) {
+	if (leapyear(1900 + year)) {
+	    days++;
+	}
+    }
+    for (month = 0; month < tm->tm_mon; month++) {
+	days += monthlen[leapyear(1900 + year)][month];
+    }
+    days += tm->tm_mday - 1;
+
+    return ((((days * 24) + tm->tm_hour) * 60 + tm->tm_min) * 60 + tm->tm_sec);
+}