[libvirt] chardev aliases [was: [RFC PATCHv2 5/5] WIP: smartcard: turn on qemu support]

[Daniel P. Berrange]

On Tue, Jan 25, 2011 at 03:04:57PM -0700, Eric Blake wrote:
> On 01/14/2011 06:46 AM, Daniel P. Berrange wrote:
> >> The 'id' setting for the chardev should really have a prefix
> >> on it, because we won't want it to be the same as the 'id'
> >> setting used for the -device option.
> > 
> > This is in fact a pre-existing flaw in our chardev handling
> > which we need to fix. The 'qemuBuildChrChardevStr' API & its
> > callers are buggy. They takes the assigned alias from the XML
> > and use it directly for the chardev. So we end up with
> > 
> >    -chardev pty,id=$alias
> >    -device isa-serial,chardev=$alias
> > 
> > The serial/parallel/channels -device args are all missing
> > any 'id' property entirely which is bad, because it means
> > we won't be able to support hotplug. What we should be
> > generating is
> > 
> >    -chardev pty,id=cdev$alias
> >    -device isa-serial,id=$alias,chardev=cdev$alias
> > 
> > So that both parts have a unique identifier assigned,
> > and the alias from the XML is associated with the
> > '-device' arg, and the -chardev is a derivative.
> 
> Done with the attached patch. git send-email won't let me send it
> directly, since it has a line longer than SMTP limits for inline mail:
> 
> fatal:
> /tmp/canS3cO9Y0/0001-qemu-use-separate-alias-for-chardev-and-associated-d.patch:
> 163: patch contains a line longer than 998 characters
> warning: no patches were sent
> 
> -- 
> Eric Blake   eblake at redhat.com    +1-801-349-2682
> Libvirt virtualization library http://libvirt.org

> From d4a3f317dbd6b5b513b505d0eee21f9ec1a2d362 Mon Sep 17 00:00:00 2001
> From: Eric Blake <eblake at redhat.com>
> Date: Tue, 25 Jan 2011 14:59:50 -0700
> Subject: [PATCH] qemu: use separate alias for chardev and associated device
> 
> * src/qemu/qemu_command.c (qemuBuildChrChardevStr): Alter the
> chardev alias.
> (qemuBuildCommandLine): Output an id for the chardev counterpart.
> * tests/qemuxml2argvdata/*: Update tests to match.
> Reported by Daniel P. Berrange.
> ---
>  src/qemu/qemu_command.c                            |   36 +++++++++++---------
>  .../qemuxml2argv-channel-guestfwd.args             |    2 +-
>  .../qemuxml2argv-channel-virtio-auto.args          |    2 +-
>  .../qemuxml2argv-channel-virtio.args               |    2 +-
>  .../qemuxml2argv-console-compat-chardev.args       |    2 +-
>  .../qemuxml2argv-console-virtio.args               |    2 +-
>  .../qemuxml2argv-parallel-tcp-chardev.args         |    2 +-
>  .../qemuxml2argv-serial-dev-chardev.args           |    2 +-
>  .../qemuxml2argv-serial-file-chardev.args          |    2 +-
>  .../qemuxml2argv-serial-many-chardev.args          |    2 +-
>  .../qemuxml2argv-serial-pty-chardev.args           |    2 +-
>  .../qemuxml2argv-serial-tcp-chardev.args           |    2 +-
>  .../qemuxml2argv-serial-tcp-telnet-chardev.args    |    2 +-
>  .../qemuxml2argv-serial-udp-chardev.args           |    2 +-
>  .../qemuxml2argv-serial-unix-chardev.args          |    2 +-
>  .../qemuxml2argv-serial-vc-chardev.args            |    2 +-
>  16 files changed, 35 insertions(+), 31 deletions(-)

ACK

Daniel