imagetest-qemu/runqueue: Since we no longer support BUILDDIR, use TMPDIR

Commit 993672fa2739794a6dd0dbd7bb232fa60522b897 removed the BUILDDIR
support from runqueue which broke the imagetest-qemu integration. We now
therefore need to set TMPDIR and pass this through the environment to
ensure the runqueue script finds the right locations without running
bitbake directly.

This patch also adds a sleep to the qemu command in the error case so that
this remains on the screen for a period of time so the user can see errors
more easily.

This change unbreaks automated testing failures on the autobuilder.

(From OE-Core rev: de470333dbdeea444199340e4cd458c13fed6a5a)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

scripts/qemuimage-testlib

@@ -457,6 +457,7 @@ Test_Create_Qemu()
 		timeout=50
 	else
 		rm -rf $TEST_ROOTFS_IMAGE
+		echo "Copying rootfs $ROOTFS_IMAGE to $TEST_ROOTFS_IMAGE"
 		$CP $ROOTFS_IMAGE $TEST_ROOTFS_IMAGE
 		if [ $? -ne 0 ]; then
 			Test_Info "Image ${ROOTFS_IMAGE} copy to ${TEST_ROOTFS_IMAGE} failed, return fail"
@@ -466,8 +467,8 @@ Test_Create_Qemu()
 		export MACHINE=$QEMUARCH
 
 		# Create Qemu in localhost VNC Port 1
-		echo "Running xterm -display ${DISPLAY} -e 'BUILDDIR=${TOPDIR} ${RUNQEMU} ${KERNEL} ${TEST_ROOTFS_IMAGE}' &"
-	    	xterm -display ${DISPLAY} -e "BUILDDIR=${TOPDIR} ${RUNQEMU} ${KERNEL} ${TEST_ROOTFS_IMAGE}" &
+		echo "Running xterm -display ${DISPLAY} -e 'TMPDIR=${TMPDIR} ${RUNQEMU} ${KERNEL} ${TEST_ROOTFS_IMAGE} && /bin/sleep 60' &"
+	    	xterm -display ${DISPLAY} -e "TMPDIR=${TMPDIR} ${RUNQEMU} ${KERNEL} ${TEST_ROOTFS_IMAGE} && /bin/sleep 60" &
 	
 		# Get the pid of the xterm processor, which will be used in Test_Kill_Qemu
 		PID=$!

scripts/runqemu

@@ -55,8 +55,6 @@ SCRIPT_QEMU_OPT=""
 SCRIPT_QEMU_EXTRA_OPT=""
 SCRIPT_KERNEL_OPT=""
 
-TMPDIR=""
-
 # Determine whether the file is a kernel or QEMU image, and set the
 # appropriate variables
 process_filename() {