selftests: forwarding: lib: Add sysctl_set(), sysctl_restore()

pmachata · davem330 · commit f5ae57784ba8 · 2018-05-03T13:37:02.000-04:00
Add two helper functions: sysctl_set() to change the value of a given
sysctl setting, and sysctl_restore() to change it back to what it was.

Signed-off-by: Petr Machata &lt;petrm@mellanox.com&gt;
Reviewed-by: Ido Schimmel &lt;idosch@mellanox.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
diff --git a/tools/testing/selftests/net/forwarding/lib.sh b/tools/testing/selftests/net/forwarding/lib.sh
@@ -381,6 +381,23 @@ bridge_ageing_time_get()
 	echo $((ageing_time / 100))
 }
 
+declare -A SYSCTL_ORIG
+sysctl_set()
+{
+	local key=$1; shift
+	local value=$1; shift
+
+	SYSCTL_ORIG[$key]=$(sysctl -n $key)
+	sysctl -qw $key=$value
+}
+
+sysctl_restore()
+{
+	local key=$1; shift
+
+	sysctl -qw $key=${SYSCTL_ORIG["$key"]}
+}
+
 forwarding_enable()
 {
        ipv4_fwd=$(sysctl -n net.ipv4.conf.all.forwarding)
