qemu-iotests: Add basic ability to use binary sample images

For image formats that are not "QEMU native", but supported for
compatibility, it is useful to verify that an image created with
the 'gold standard' native tool can be read / written to successfully
by QEMU.

In addition to testing non-native images, this could also be useful to
test against image files created by older versions of QEMU.

This provides a directory to store small sample images, for use by
scripts in tests/qemu-iotests.

Image files should be compressed with bzip2.

To use a sample image from a bash script, the _use_sample_img function
will copy and decompress the image into $TEST_DIR, and set $TEST_IMG to
be the decompressed sample image copy.  To cleanup, call
_cleanup_test_img as normal.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

3 files changed, 35 insertions, 0 deletions

diff --git a/tests/qemu-iotests/common.config b/tests/qemu-iotests/common.config
index d794e62..d90a8bc 100644
--- a/tests/qemu-iotests/common.config
+++ b/tests/qemu-iotests/common.config
@@ -125,6 +125,17 @@ fi
 
 export TEST_DIR
 
+if [ -z "$SAMPLE_IMG_DIR" ]; then
+        SAMPLE_IMG_DIR=`pwd`/sample_images
+fi
+
+if [ ! -d "$SAMPLE_IMG_DIR" ]; then
+    echo "common.config: Error: \$SAMPLE_IMG_DIR ($SAMPLE_IMG_DIR) is not a directory"
+    exit 1
+fi
+
+export SAMPLE_IMG_DIR
+
 _readlink()
 {
     if [ $# -ne 1 ]; then
diff --git a/tests/qemu-iotests/common.rc b/tests/qemu-iotests/common.rc
index 28b39e4..6730955 100644
--- a/tests/qemu-iotests/common.rc
+++ b/tests/qemu-iotests/common.rc
@@ -91,6 +91,18 @@ _set_default_imgopts()
     fi
 }
 
+_use_sample_img()
+{
+    SAMPLE_IMG_FILE="${1%\.bz2}"
+    TEST_IMG="$TEST_DIR/$SAMPLE_IMG_FILE"
+    bzcat "$SAMPLE_IMG_DIR/$1" > "$TEST_IMG"
+    if [ $? -ne 0 ]
+    then
+        echo "_use_sample_img error, cannot extract '$SAMPLE_IMG_DIR/$1'"
+        exit 1
+    fi
+}
+
 _make_test_img()
 {
     # extra qemu-img options can be added by tests
@@ -158,6 +170,10 @@ _cleanup_test_img()
             rm -f $TEST_DIR/t.$IMGFMT
             rm -f $TEST_DIR/t.$IMGFMT.orig
             rm -f $TEST_DIR/t.$IMGFMT.base
+            if [ -n "$SAMPLE_IMG_FILE" ]
+            then
+                rm -f "$TEST_DIR/$SAMPLE_IMG_FILE"
+            fi
             ;;
 
         rbd)
diff --git a/tests/qemu-iotests/sample_images/README b/tests/qemu-iotests/sample_images/README
new file mode 100644
index 0000000..507af5f
--- /dev/null
+++ b/tests/qemu-iotests/sample_images/README
@@ -0,0 +1,8 @@
+This is for small sample images to be used with qemu-iotests, intended for
+non-native formats that QEMU supports for compatibility.  The idea is to use
+the native tool to create the sample image.
+
+For instance, a VHDX image in this directory would be an image created not by
+QEMU itself, but rather created by Hyper-V.
+
+Sample images added here must be compressed with bzip2.