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Date: Wed, 15 May 2013 08:44:57 +0200
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 2/4] vnc: Support for LED state extension
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To: Lei Li <lilei@linux.vnet.ibm.com>
Cc: lagarcia@br.ibm.com, aliguori@us.ibm.com, Laszlo Ersek <lersek@redhat.com>, qemu-devel@nongnu.org

On 05/15/13 08:05, Lei Li wrote:
> On 05/14/2013 07:35 PM, Gerd Hoffmann wrote:
>> On 04/25/13 07:29, Lei Li wrote:
>>> +    /* Sending the current led state message to the client */
>>> +    if (ledstate != current_led_state(vs)) {
>>> +        vnc_led_state_change(vs);
>>> +    }
>> This check never becomes true as the vnc modifier/led state just got
>> updated to match ledstate ...
> 
> Oh... then how about get rid of this check, let vnc_led_state_change send
> the current led state message directly?

Only sending an update if something did actually change makes sense I
think, but you need to check before updating the state, i.e. something
like this:

  bool has_changed = ledstate != current_led_state(vs);

  [ update modifiers/led state ]

  if (has_changed)
     vnc_led_state_change()

cheers,
  Gerd