[PATCH 2/6] Input: Don't freeze unrelated devices in DeliverGrabbedEvent

[Simon Thum]

On 02/15/2011 12:27 PM, Daniel Stone wrote:
> When delivering an event to a device grabbed with SyncBoth,
> DeliverGrabbedEvent walks the device tree looking for associated devices
> to freeze them.  Unfortunately, it froze all devices instead of just the
> paired device, and the previous fix in 4fbadc8b17237f3c would still break
> if the same client had a non-SyncBoth grab on another unrelated master
> device.
> 
> Fix this by completely ignoring devices that aren't our paired device.
> 
> Signed-off-by: Daniel Stone <daniel at fooishbar.org>
> ---
>  dix/events.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/dix/events.c b/dix/events.c
> index 5e8166d..80792ee 100644
> --- a/dix/events.c
> +++ b/dix/events.c
> @@ -3884,14 +3884,14 @@ DeliverGrabbedEvent(InternalEvent *event, DeviceIntPtr thisDev,
>  	case FREEZE_BOTH_NEXT_EVENT:
>  	    for (dev = inputInfo.devices; dev; dev = dev->next)
>  	    {
> -		if (dev == thisDev)
> +		if (dev == thisDev || dev != GetPairedDevice(thisDev))
>  		    continue;
I wonder if it's worth traversing the list since you know both devices.
Moving that into a function called twice instead of in a loop might help
readability. It also avoids repeated GetPairedDevice calls.

Cheers,

Simon



>  		FreezeThaw(dev, TRUE);
>  		if ((dev->deviceGrab.sync.state == FREEZE_BOTH_NEXT_EVENT) &&
>  		    (CLIENT_BITS(grab->resource) ==
>  		     CLIENT_BITS(dev->deviceGrab.grab->resource)))
>  		    dev->deviceGrab.sync.state = FROZEN_NO_EVENT;
> -		else if (GetPairedDevice(thisDev) == dev)
> +		else
>                      dev->deviceGrab.sync.other = grab;
>  	    }
>  	    /* fall through */