[PATCH 09/10] fix: only append kargs and extra_kargs if set

[Felix Moessbauer <felix.moessbauer@siemens.com>]

This fixes an issue when no KARGS and no EXTRA_KARGS where set, leading
to an empty string after -append. This happens for instance when booting
a WIC image instead of performing a direct kernel boot.

Instead of always adding -append, we only add it if at least on of the
variables is set.

Signed-off-by: Felix Moessbauer <felix.moessbauer@siemens.com>
---
 scripts/start_vm | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/scripts/start_vm b/scripts/start_vm
index 8876e53..3c0ba16 100755
--- a/scripts/start_vm
+++ b/scripts/start_vm
@@ -19,6 +19,7 @@ bb2sh() {
 start_qemu() {
     root=`echo $QEMU_DISK_ARGS \
         | sed 's,##ROOTFS_IMAGE##,'$IMAGE_DIR/$ROOTFS_IMAGE','`
+    [ -n "$KARGS$EXTRA_KARGS" ] && OPT_KERNEL_ARGS="-append $KARGS$EXTRA_KARGS"
     local had_x
     echo $- | grep -q x && had_x=1 || had_x=0
     [ $had_x -eq 0 ] && set -x
@@ -28,7 +29,7 @@ start_qemu() {
 	$QCPU \
 	-nographic \
 	$EXTRA_ARGS \
-        -append "$KARGS$EXTRA_KARGS" \
+    $OPT_KERNEL_ARGS \
 	$root
     [ $had_x -eq 0 ] && set +x
 }
-- 
2.34.1