tests: Add a test for running qemu in a container

The qemu backend defaults to running against a locally installed
qemu but falls back to running in a container if qemu is not
installed. This test explicitly tests that the containerised
qemu backend works only if there is a locally installed qemu.

Signed-off-by: Rolf Neugebauer <rolf.neugebauer@docker.com>

test/cases/010_platforms/000_qemu/100_container/test.sh

@@ -0,0 +1,35 @@
+#!/bin/sh
+# SUMMARY: Check that qemu runs containerised
+# LABELS:
+# AUTHOR: Rolf Neugebauer <rolf.neugebauer@docker.com>
+
+set -e
+
+# Source libraries. Uncomment if needed/defined
+#. "${RT_LIB}"
+. "${RT_PROJECT_ROOT}/_lib/lib.sh"
+
+NAME=qemu-kernel
+
+clean_up() {
+	# remove any files, containers, images etc
+	rm -rf ${NAME}* || true
+}
+
+trap clean_up EXIT
+
+# check if qemu is installed locally
+QEMU=$(command -v qemu-system-x86_64 || true)
+if [ -z "${QEMU}" ]; then
+    # No qemu installed so don't bother to test as all the other
+    # qemu tests would have been run containerised
+    echo "No locally installed qemu"
+    exit $RT_CANCEL
+fi
+
+moby build -name "${NAME}" test.yml
+[ -f "${NAME}-kernel" ] || exit 1
+[ -f "${NAME}-initrd.img" ] || exit 1
+[ -f "${NAME}-cmdline" ]|| exit 1
+linuxkit run qemu -containerized "${NAME}" | grep -q "Welcome to LinuxKit"
+exit 0

test/cases/010_platforms/000_qemu/100_container/test.yml

@@ -0,0 +1,16 @@
+kernel:
+  image: "linuxkit/kernel:4.9.x"
+  cmdline: "console=ttyS0 console=tty0 page_poison=1"
+init:
+  - linuxkit/init:cbd7ae748f0a082516501a3e914fa0c924ee941e
+  - linuxkit/runc:24dfe632ed3ff53a026ee3fac046fd544434e2d6
+  - linuxkit/containerd:f1130450206d4f64f0ddc13d15bb68435aa1ff61
+onboot:
+  - name: poweroff
+    image: "linuxkit/poweroff:a8f1e4ad8d459f1fdaad9e4b007512cb3b504ae8"
+    command: ["/bin/sh", "/poweroff.sh", "3"]
+trust:
+  image:
+    - linuxkit/kernel
+outputs:
+  - format: kernel+initrd