Re: [Qemu-devel] QMP's chardev-add less capable than HMP's

[Gerd Hoffmann]

On 02/06/13 15:35, Markus Armbruster wrote:
> As a general rule, HMP commands must be built on top of the QMP API.
> Luiz and others have worked long & hard to make HMP conform to this
> rule.
> 
> However, a new command has crept in that violates it.
> 
> QMP's chardev-add runs qmp_chardev_add(), which supports backends
> 
> * file with parameters in, out
> 
> * port with parameters type (serial, parallel), device
> 
> * socket with parameters addr, server, wait, nodelay, telnet
> 
> * pty
> 
> * null
> 
> HMP's chardev-add runs hmp_chardev_add(), which is *not* built on to of
> QMP.  Instead, it uses qemu_chr_new_from_opts(), which looks more
> powerful to me.  Additional backends: udp, msmouse, vc, memory, pipe,
> stdio, braille, tty, spicevmc, spiceport.  I haven't checked whether the
> backends that are available in QMP support all the parameters that HMP
> does.

Future plan is to add support for the missing ones to QMP,
then switch over qemu_chr_new_from_opts to create ChardevBackend and use
the new QMP code path for initialization everywhere.  Once this point is
reached both HMP and QMP will provide identical features.

Obviously that isn't an option for 1.4.

> If we're 100% serious about the rule, we need to disable HMP chardev-add
> for the release.

Fine with me.

cheers,
  Gerd