qemu-iotests: Add 043 backing file chain infinite loop test

This new test verifies that qemu-img info --backing-chain safely aborts
when an image file has a backing file infinite loop.

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

tests/qemu-iotests/043

@@ -0,0 +1,95 @@
+#!/bin/bash
+#
+# Test that qemu-img info --backing-chain detects infinite loops
+#
+# Copyright (C) 2012 Red Hat, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+# creator
+owner=stefanha@redhat.com
+
+seq=`basename $0`
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1	# failure is the default!
+
+_cleanup()
+{
+    _cleanup_test_img
+    rm -f $TEST_IMG.[123].base
+}
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+# get standard environment, filters and checks
+. ./common.rc
+. ./common.filter
+
+# Any format supporting backing files
+_supported_fmt qcow qcow2 vmdk qed
+_supported_proto generic
+_supported_os Linux
+
+
+size=128M
+_make_test_img $size
+$QEMU_IMG rebase -u -b $TEST_IMG $TEST_IMG
+
+echo
+echo "== backing file references self =="
+_img_info --backing-chain
+
+_make_test_img $size
+mv $TEST_IMG $TEST_IMG.base
+_make_test_img -b $TEST_IMG.base $size
+$QEMU_IMG rebase -u -b $TEST_IMG $TEST_IMG.base
+
+echo
+echo "== parent references self =="
+_img_info --backing-chain
+
+_make_test_img $size
+mv $TEST_IMG $TEST_IMG.1.base
+_make_test_img -b $TEST_IMG.1.base $size
+mv $TEST_IMG $TEST_IMG.2.base
+_make_test_img -b $TEST_IMG.2.base $size
+mv $TEST_IMG $TEST_IMG.3.base
+_make_test_img -b $TEST_IMG.3.base $size
+$QEMU_IMG rebase -u -b $TEST_IMG.2.base $TEST_IMG.1.base
+
+echo
+echo "== ancestor references another ancestor =="
+_img_info --backing-chain
+
+_make_test_img $size
+mv $TEST_IMG $TEST_IMG.1.base
+_make_test_img -b $TEST_IMG.1.base $size
+mv $TEST_IMG $TEST_IMG.2.base
+_make_test_img -b $TEST_IMG.2.base $size
+
+echo
+echo "== finite chain of length 3 (human) =="
+_img_info --backing-chain
+
+echo
+echo "== finite chain of length 3 (json) =="
+_img_info --backing-chain --output=json
+
+# success, all done
+echo "*** done"
+rm -f $seq.full
+status=0

tests/qemu-iotests/043.out

@@ -0,0 +1,66 @@
+QA output created by 043
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 
+
+== backing file references self ==
+qemu-img: Backing file 'TEST_DIR/t.IMGFMT' creates an infinite loop.
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file='TEST_DIR/t.IMGFMT.base' 
+
+== parent references self ==
+qemu-img: Backing file 'TEST_DIR/t.IMGFMT' creates an infinite loop.
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file='TEST_DIR/t.IMGFMT.1.base' 
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file='TEST_DIR/t.IMGFMT.2.base' 
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file='TEST_DIR/t.IMGFMT.3.base' 
+
+== ancestor references another ancestor ==
+qemu-img: Backing file 'TEST_DIR/t.IMGFMT.2.base' creates an infinite loop.
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file='TEST_DIR/t.IMGFMT.1.base' 
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file='TEST_DIR/t.IMGFMT.2.base' 
+
+== finite chain of length 3 (human) ==
+image: TEST_DIR/t.IMGFMT
+file format: IMGFMT
+virtual size: 128M (134217728 bytes)
+cluster_size: 65536
+backing file: TEST_DIR/t.IMGFMT.2.base
+
+image: TEST_DIR/t.IMGFMT.2.base
+file format: IMGFMT
+virtual size: 128M (134217728 bytes)
+cluster_size: 65536
+backing file: TEST_DIR/t.IMGFMT.1.base
+
+image: TEST_DIR/t.IMGFMT.1.base
+file format: IMGFMT
+virtual size: 128M (134217728 bytes)
+cluster_size: 65536
+
+== finite chain of length 3 (json) ==
+[
+    {
+        "virtual-size": 134217728, 
+        "filename": "TEST_DIR/t.IMGFMT", 
+        "cluster-size": 65536, 
+        "format": "IMGFMT", 
+        "backing-filename": "TEST_DIR/t.IMGFMT.2.base", 
+        "dirty-flag": false
+    }, 
+    {
+        "virtual-size": 134217728, 
+        "filename": "TEST_DIR/t.IMGFMT.2.base", 
+        "cluster-size": 65536, 
+        "format": "IMGFMT", 
+        "backing-filename": "TEST_DIR/t.IMGFMT.1.base", 
+        "dirty-flag": false
+    }, 
+    {
+        "virtual-size": 134217728, 
+        "filename": "TEST_DIR/t.IMGFMT.1.base", 
+        "cluster-size": 65536, 
+        "format": "IMGFMT", 
+        "dirty-flag": false
+    }
+]
+*** done

tests/qemu-iotests/common.rc

@@ -145,6 +145,16 @@ _check_test_img()
     	sed -e 's/qemu-img\: This image format does not support checks/No errors were found on the image./'
 }
 
+_img_info()
+{
+    $QEMU_IMG info "$@" $TEST_IMG 2>&1 | \
+        sed -e "s#$IMGPROTO:$TEST_DIR#TEST_DIR#g" \
+            -e "s#$TEST_DIR#TEST_DIR#g" \
+            -e "s#$IMGFMT#IMGFMT#g" \
+            -e "/^disk size:/ D" \
+            -e "/actual-size/ D"
+}
+
 _get_pids_by_name()
 {
     if [ $# -ne 1 ]

tests/qemu-iotests/group

@@ -48,3 +48,4 @@
 039 rw auto
 040 rw auto
 042 rw auto quick
+043 rw auto backing