Re: [Qemu-devel] [PATCH 3/3] qapi: convert sendkey

[Luiz Capitulino]

On Fri, 25 May 2012 14:12:39 +0100
"Daniel P. Berrange" <address@hidden> wrote:

> On Fri, May 25, 2012 at 10:06:11AM -0300, Luiz Capitulino wrote:
> > On Fri, 25 May 2012 08:34:54 +0100
> > "Daniel P. Berrange" <address@hidden> wrote:
> > 
> > > On Fri, May 25, 2012 at 02:20:33PM +0800, Amos Kong wrote:
> > > > On 25/05/12 11:51, Eric Blake wrote:
> > > > >On 05/24/2012 09:32 PM, Amos Kong wrote:
> > > > >>Convert 'sendkey' to use. do_sendkey() depends on some variables
> > > > >>in monitor.c, so reserve qmp_sendkey() to monitor.c
> > > > >>Rename 'string' to 'keys', rename 'hold_time' to 'hold-time'
> > > > >>
> > > > >>Signed-off-by: Amos Kong<address@hidden>
> > > > >
> > > > >>+##
> > > > >>+# @sendkey:
> > > > >>+#
> > > > >>+# Send keys to VM.
> > > > >>+#
> > > > >>+# @keys: key sequence
> > > > >>+# @hold-time: time to delay key up events
> > > > >>+#
> > > > >>+# Returns: Nothing on success
> > > > >>+#          If key is unknown or redundant, QERR_INVALID_PARAMETER
> > > > >>+#          If key is invalid, QERR_INVALID_PARAMETER_VALUE
> > > > >>+#
> > > > >>+# Notes: Send @var{keys} to the emulator. @var{keys} could be the 
> > > > >>name of the
> > > > >>+#        key or the raw value in either decimal or hexadecimal  
> > > > >>format. Use
> > > > >>+#        @code{-} to press several keys simultaneously.
> > > > >>+#
> > > > >>+# Since: 0.14.0
> > > > >>+##
> > > > >>+{ 'command': 'sendkey', 'data': {'keys': 'str', '*hold-time': 'int'} 
> > > > >>}
> > > > >
> > > > >Rather than making 'keys' a free-form string where qemu then has to
> > > > >parse '-' to separate keys, should we instead make it a JSON array?  
> > > > >For
> > > > >example,
> > > > 
> > > > 
> > > > Anthony, Luiz, Daniel,  what's your opinion?
> > > 
> > > Using a JSON array for the key names does seem like the most
> > > natural way to model this. A good rule of thumb is that the
> > > implementation of a command should not need to further
> > > parse the individual parameter values. Using a magic string
> > > encoding instead of the JSON array requires such extra special
> > > case parsing.
> > 
> > That's true, and I agree this is better.
> > 
> > Just would like to point out that we can't go too far on improving
> > HMP-inherited commands, as our goal here is to convert most (or every 
> > single)
> > HMP commands to QMP. If we go far on improving commands, we'll get stuck as 
> > we
> > did some time ago.
> > 
> > Btw, I remember someone saying that when libvirt wants to use a HMP command 
> > it
> > first checks if the command exists in QMP before using passthrough. In that 
> > case,
> > how will libvirt behave if we change the arguments?
> 
> We're not talking about changing the args of the existing HMP command,
> and libvirt has no code for a QMP version of sendkey, so there's no
> compatibility issue.

Good.