[libvirt] PATCH: Support setting QEMU disk driver type

[Jim Meyering]

"Daniel P. Berrange" <berrange at redhat.com> wrote:
> The domain XML has long supported ability to set the disk driver type
> but we only used it in Xen so far.
>
> This patch adds support for QEMU usage. In this usage the driver name
> is always going to be 'qemu' since all backends are in QEMU, no alternate
> kernelspace / helper daemons as with Xen. The driver type will be one of
> the valid QEMU disk formats.
>
> eg
>
>   <driver name='qemu' type='qcow2'/>
>
>
> The snprintf() stuff for building the disk parameter string was getting
> rather out of hand, so I took the opportunity to switch it over to use
> the virBuffer routines.
>
>  src/qemu_conf.c                                              |   49 ++++++++---
>  tests/qemuxml2argvdata/qemuxml2argv-disk-drive-fmt-qcow.args |    1
>  tests/qemuxml2argvdata/qemuxml2argv-disk-drive-fmt-qcow.xml  |   29 ++++++
>  tests/qemuxml2argvtest.c                                     |    2
>  tests/qemuxml2xmltest.c                                      |    1
>  5 files changed, 69 insertions(+), 13 deletions(-)

ACK.  much more readable that way.