[PATCH 3/2] qemu-img: Improve error for rebase without backing format

[Kevin Wolf]

Am 08.07.2021 um 17:52 hat Eric Blake geschrieben:
> When removeing support for qemu-img being able to create backing
> chains without embedded backing formats, we caused a poor error
> message as caught by iotest 114.  Improve the situation to inform the
> user what went wrong.
> 
> Suggested-by: Kevin Wolf <kwolf at redhat.com>
> Signed-off-by: Eric Blake <eblake at redhat.com>

> diff --git a/tests/qemu-iotests/114.out b/tests/qemu-iotests/114.out
> index 172454401257..016e9ce3ecfb 100644
> --- a/tests/qemu-iotests/114.out
> +++ b/tests/qemu-iotests/114.out
> @@ -14,7 +14,7 @@ qemu-io: can't open device TEST_DIR/t.qcow2: Could not open backing file: Unknow
>  no file open, try 'help open'
>  read 4096/4096 bytes at offset 0
>  4 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> -qemu-img: Could not change the backing file to '/home/eblake/qemu/build/tests/qemu-iotests/scratch/t.qcow2.base': Invalid argument
> +qemu-img: Could not change the backing file to '/home/eblake/qemu/build/tests/qemu-iotests/scratch/t.qcow2.base': backing format must be specified
>  read 4096/4096 bytes at offset 0
>  4 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
>  *** done

Wait, there is a problem in the image path...

I'm squashing in the following for patch 2, and will do the obvious
conflict resolution for this one.

Kevin

diff --git a/tests/qemu-iotests/114 b/tests/qemu-iotests/114
index 3e30b402bc..de6fd327ee 100755
--- a/tests/qemu-iotests/114
+++ b/tests/qemu-iotests/114
@@ -65,7 +65,7 @@ $QEMU_IO -c "open $TEST_IMG" -c "read 0 4k" 2>&1 | _filter_qemu_io | _filter_tes
 $QEMU_IO -c "open -o backing.driver=$IMGFMT $TEST_IMG" -c "read 0 4k" | _filter_qemu_io

 # Rebase the image, to show that backing format is required.
-$QEMU_IMG rebase -u -b "$TEST_IMG.base" "$TEST_IMG" && echo "unexpected pass"
+($QEMU_IMG rebase -u -b "$TEST_IMG.base" "$TEST_IMG" 2>&1 && echo "unexpected pass") | _filter_testdir
 $QEMU_IMG rebase -u -b "$TEST_IMG.base" -F $IMGFMT "$TEST_IMG"
 $QEMU_IO -c "open $TEST_IMG" -c "read 0 4k" 2>&1 | _filter_qemu_io | _filter_testdir

diff --git a/tests/qemu-iotests/114.out b/tests/qemu-iotests/114.out
index 1724544012..f51dd9d20a 100644
--- a/tests/qemu-iotests/114.out
+++ b/tests/qemu-iotests/114.out
@@ -14,7 +14,7 @@ qemu-io: can't open device TEST_DIR/t.qcow2: Could not open backing file: Unknow
 no file open, try 'help open'
 read 4096/4096 bytes at offset 0
 4 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-qemu-img: Could not change the backing file to '/home/eblake/qemu/build/tests/qemu-iotests/scratch/t.qcow2.base': Invalid argument
+qemu-img: Could not change the backing file to 'TEST_DIR/t.qcow2.base': backing format must be specified
 read 4096/4096 bytes at offset 0
 4 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 *** done