[libvirt] [PATCH 08/10 V2] send-key: Implementing the remote protocol

[Daniel P. Berrange]

On Tue, Jun 14, 2011 at 11:21:39AM +0200, Matthias Bolte wrote:
> 2011/6/14 Daniel P. Berrange <berrange at redhat.com>:
> > On Tue, Jun 07, 2011 at 05:11:15PM +0800, Lai Jiangshan wrote:
> >> Signed-off-by: Lai Jiangshan <laijs at cn.fujitsu.com>
> >> ---
> >>  src/remote/remote_driver.c   |    1 +
> >>  src/remote/remote_protocol.x |   16 +++++++++++++++-
> >>  src/remote_protocol-structs  |   11 +++++++++++
> >>  3 files changed, 27 insertions(+), 1 deletions(-)
> >>
> >> diff --git a/src/remote/remote_driver.c b/src/remote/remote_driver.c
> >> index 8335a1a..f08a609 100644
> >> --- a/src/remote/remote_driver.c
> >> +++ b/src/remote/remote_driver.c
> >> @@ -6337,6 +6337,7 @@ static virDriver remote_driver = {
> >>      .domainMigratePerform3 = remoteDomainMigratePerform3, /* 0.9.2 */
> >>      .domainMigrateFinish3 = remoteDomainMigrateFinish3, /* 0.9.2 */
> >>      .domainMigrateConfirm3 = remoteDomainMigrateConfirm3, /* 0.9.2 */
> >> +    .domainSendKey = remoteDomainSendKey, /* 0.9.3 */
> >>  };
> >>
> >>  static virNetworkDriver network_driver = {
> >> diff --git a/src/remote/remote_protocol.x b/src/remote/remote_protocol.x
> >> index c9b8cff..2126325 100644
> >> --- a/src/remote/remote_protocol.x
> >> +++ b/src/remote/remote_protocol.x
> >> @@ -191,6 +191,11 @@ const REMOTE_SECRET_UUID_LIST_MAX = 16384;
> >>   */
> >>  const REMOTE_CPU_BASELINE_MAX = 256;
> >>
> >> +/*
> >> + * Max number of sending keycodes.
> >> + */
> >> +const REMOTE_SEND_KEY_MAX = 16;
> >
> > Should call this  REMOTE_DOMAIN_SEND_KEY_MAX really
> >
> 
> And I still wonder why we go with such a low limit here that is not
> documented anywhere. If an applications tries to send 17 key strokes
> in one call it'll just fail with an RPC error.

Perhaps it can be raised, but really this API is only for doing things
like sending magic key combinations like Ctrl-Alt-Delete,  Ctrl+F12 etc.

It isn't suitable for sending large volumes of text, for the same
reason we don't want todo that via GTK-VNC:

  http://mail.gnome.org/archives/gtk-vnc-list/2010-December/msg00004.html

  "Another fairly serious problem is that if you paste a few kilobytes
   of data then you're pushing the keyboard input stack incredibly hard.
   These interfaces are designed for human typing speeds and even a few
   kilobytes will drive Thunderbird (say) to distraction.   Tens of
   kilobytes will probably lock you out for longer than you're prepared
   to wait."

Of course '16' is no where near kilobytes, so perhaps we can raise it
a little, but I don't think we should give application developers the
idea that this is useful for sending large data volumes.

Regards,
Daniel
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