[libvirt] [PATCH] qemu: Don't bother user with libvirt-internal paths

[Pavel Hrdina]

On Wed, Jan 06, 2016 at 05:50:57PM +0100, Martin Kletzander wrote:
> If user defines a virtio channel with UNIX socket backend and doesn't
> care about the path for the socket (e.g. qemu-agent channel), we still
> generate it into the persistent XML.  Moreover when then user renames
> the domain, due to its persistent socket path saved into the per-domain
> directory, it will not start.  So let's forget about old generated paths
> and also stop putting them into the persistent definition.
> 
> https://bugzilla.redhat.com/show_bug.cgi?id=1278068
> 
> Signed-off-by: Martin Kletzander <mkletzan at redhat.com>
> ---
>  src/qemu/qemu_command.c                             | 12 ++++++++++++
>  src/qemu/qemu_domain.c                              | 21 +++++++++++----------
>  .../qemuxml2argv-channel-virtio-unix.args           |  5 ++++-
>  .../qemuxml2argv-channel-virtio-unix.xml            |  4 ++++
>  4 files changed, 31 insertions(+), 11 deletions(-)
> 
> diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
> index 66ca11152ad8..c5127cfa04f9 100644
> --- a/src/qemu/qemu_command.c
> +++ b/src/qemu/qemu_command.c
> @@ -10510,6 +10510,18 @@ qemuBuildCommandLine(virConnectPtr conn,
>                  goto error;
>              }
> 
> +            if (channel->source.type == VIR_DOMAIN_CHR_TYPE_UNIX &&
> +                !channel->source.data.nix.path) {
> +                if (virAsprintf(&channel->source.data.nix.path,
> +                                "%s/domain-%s/%s",
> +                                cfg->channelTargetDir, def->name,
> +                                channel->target.name ? channel->target.name
> +                                : "unknown.sock") < 0)
> +                    goto error;
> +
> +                channel->source.data.nix.listen = true;
> +            }
> +

I don't like this.  The qemuBuildCommandLine function should only create a
command line, not modify the domain definition.  I know, there are other places,
that do the same, but let's try to avoid it.

>              if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE_SPICEVMC) &&
>                  channel->source.type == VIR_DOMAIN_CHR_TYPE_SPICEVMC) {
>                  /* spicevmc was originally introduced via a -device
> diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c

[...]

Otherwise it looks good.

Pavel