Re: [Qemu-devel] [PATCH v3 1/2] iotest 033: add misaligned write-zeroes test via truncate

[Eric Blake <eblake@redhat.com>]

On 02/14/2018 10:09 AM, Anton Nefedov wrote:
> This new test case only makes sense for qcow2 while iotest 033 is generic;
> however it matches the test purpose perfectly and also 033 contains those
> do_test() tricks to pass the alignment, which won't look nice being
> duplicated in other tests or moved to the common code.
> 
> Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
> ---
>   tests/qemu-iotests/033     | 29 +++++++++++++++++++++++++++++
>   tests/qemu-iotests/033.out | 13 +++++++++++++
>   2 files changed, 42 insertions(+)
> 

> +# only interested in qcow2 here; also other formats might respond with
> +#  "not supported" error message
> +if [ $IMGFMT = "qcow2" ]; then
> +    do_test 512 "truncate $L2_COVERAGE" "$TEST_IMG" | _filter_qemu_io
> +fi

But without an else branch that echoes the same text as the if branch 
generates, your .out file is now broken for other image formats.  Or 
does 'qemu-io -c truncate' not produce output?

/me goes and tests...

Okay, looks like truncate is silent; and that the truncation (or 
skipping of the truncation) doesn't affect things.

Tested-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
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