From: Ed Maste <emaste@adaranet.com>
Date: Fri, 27 Jul 2012 21:27:15 +0000 (-0400)
Subject: Avoid implementation-defined strerror behaviour
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bbd1c2c5f5785bd58943afc81fb059b473ab0027;p=openvswitch

Avoid implementation-defined strerror behaviour

POSIX states that the string returned by strerror() may be overwritten
by a subsequent call (i.e., because it returns a pointer to a static
buffer).  Make a copy of one of the two strerror() strings to avoid
this.

Background: FreeBSD historically returned such a pointer only in the
case of an invalid errno.  With the addition of NLS strerror was changed
to do so for all calls.

Prior to this change I had confusing results from the test suite like
"... is 22 (Invalid argument) but should be 0 (Invalid argument)".

Signed-off-by: Ed Maste <emaste@adaranet.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
---

diff --git a/tests/test-vconn.c b/tests/test-vconn.c
index 3398c4aa..31451a27 100644
--- a/tests/test-vconn.c
+++ b/tests/test-vconn.c
@@ -56,8 +56,9 @@ static void
 check_errno(int a, int b, const char *as, const char *file, int line)
 {
     if (a != b) {
+        char *str_b = strdup(strerror(abs(b)));
         ovs_fatal(0, "%s:%d: %s is %d (%s) but should be %d (%s)",
-                  file, line, as, a, strerror(abs(a)), b, strerror(abs(b)));
+                  file, line, as, a, strerror(abs(a)), b, str_b);
     }
 }