From: Karel Zak <kzak@redhat.com>
Date: Thu, 11 Feb 2010 15:29:05 +0000 (+0100)
Subject: cal: fix first day of the week calculation on BE systems
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c3e3134eb7a252706f1efe53f6f8b5e4309a79e2;p=util-linux

cal: fix first day of the week calculation on BE systems

This reverts commit dcb54fafb128ab41772ae217afc6a7612e2cc446,
"cal: remove gcc-ism from nl_langinfo() call".

The code:

	int wfd = (int)(intptr_t) nl_langinfo(_NL_TIME_WEEK_1STDAY);

does not work on big-endian machines. The original solution based on
union is better.

Note that the "type punning" is not gcc-ism any more, it's allowed
by C99 (6.5.2.3).

Reported-by: Joseph Jezak <josejx@gentoo.org>
Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/misc-utils/cal.c b/misc-utils/cal.c
index 5444ceaf..5eb14b55 100644
--- a/misc-utils/cal.c
+++ b/misc-utils/cal.c
@@ -312,7 +312,11 @@ main(int argc, char **argv) {
 	 POSIX:  19971201 + 7 -1 = 0
 	 */
 	{
-		int wfd = (int)(intptr_t) nl_langinfo(_NL_TIME_WEEK_1STDAY);
+		int wfd;
+		union { unsigned int word; char *string; } val;
+		val.string = nl_langinfo(_NL_TIME_WEEK_1STDAY);
+
+		wfd = val.word;
 		wfd = day_in_week(wfd % 100, (wfd / 100) % 100, wfd / (100 * 100));
 		weekstart = (wfd + *nl_langinfo(_NL_TIME_FIRST_WEEKDAY) - 1) % 7;
 	}