[PATCH 09/21] Xi: split updating button count and state into helper functions

[Peter Hutterer]

On 12/12/11 15:27 , Chase Douglas wrote:
> On 12/08/2011 07:36 PM, Peter Hutterer wrote:
>> Functional change: for a button mapped to 0, the motionHintWindow is not
>> updated to the NullWindow anymore. Before it got updated unconditionally to
>> the button mapping. I have no idea what the practical effect of this is, but
>> I guess it's closer to the correct behaviour: pressing a button that's
>> logically disabled now does not disrupt the motion hint delivery.
>>
>> Signed-off-by: Peter Hutterer<peter.hutterer at who-t.net>
>> ---
>>   Xi/exevents.c |   41 +++++++++++++++++++++++++++++------------
>>   1 files changed, 29 insertions(+), 12 deletions(-)
>>
>> diff --git a/Xi/exevents.c b/Xi/exevents.c
>> index 1140554..dab467c 100644
>> --- a/Xi/exevents.c
>> +++ b/Xi/exevents.c
>> @@ -726,6 +726,32 @@ UpdateDeviceMotionMask(DeviceIntPtr device, unsigned short state,
>>       SetMaskForEvent(device->id, mask, MotionNotify);
>>   }
>>
>> +static void
>> +IncreaseButtonCount(DeviceIntPtr dev, int key, CARD8 *buttons_down,
>> +                    Mask *motion_mask, unsigned short *state)
>> +{
>> +    if (dev->valuator)
>> +        dev->valuator->motionHintWindow = NullWindow;
>> +
>> +    (*buttons_down)++;
>> +    *motion_mask = DeviceButtonMotionMask;
>> +    if (dev->button->map[key]<= 5)
>> +        *state |= (Button1Mask>>  1)<<  dev->button->map[key];
>> +}
>> +
>> +static void
>> +DecreaseButtonCount(DeviceIntPtr dev, int key, CARD8 *buttons_down,
>> +                    Mask *motion_mask, unsigned short *state)
>> +{
>> +    if (dev->valuator)
>> +        dev->valuator->motionHintWindow = NullWindow;
>> +
>> +    if (*buttons_down>= 1&&  !--(*buttons_down))
>> +        *motion_mask = 0;
>> +    if (dev->button->map[key]<= 5)
>> +        *state&= ~((Button1Mask>>  1)<<  dev->button->map[key]);
>> +}
>> +
>>   /**
>>    * Update the device state according to the data in the event.
>>    *
>> @@ -831,15 +857,11 @@ UpdateDeviceState(DeviceIntPtr device, DeviceEvent* event)
>>               return DONT_PROCESS;
>>
>>           set_button_down(device, key, BUTTON_PROCESSED);
>> -	if (device->valuator)
>> -	    device->valuator->motionHintWindow = NullWindow;
>> +
>>           if (!b->map[key])
>>               return DONT_PROCESS;
>> -        b->buttonsDown++;
>> -	b->motionMask = DeviceButtonMotionMask;
>> -        if (b->map[key]<= 5)
>> -	    b->state |= (Button1Mask>>  1)<<  b->map[key];
>>
>> +        IncreaseButtonCount(device, key,&b->buttonsDown,&b->motionMask,&b->state);
>>           UpdateDeviceMotionMask(device, b->state, b->motionMask);
>>       } else if (event->type == ET_ButtonRelease) {
>>           if (!b)
>> @@ -867,15 +889,10 @@ UpdateDeviceState(DeviceIntPtr device, DeviceEvent* event)
>>               }
>>           }
>>           set_button_up(device, key, BUTTON_PROCESSED);
>> -	if (device->valuator)
>> -	    device->valuator->motionHintWindow = NullWindow;
>>           if (!b->map[key])
>>               return DONT_PROCESS;
>> -        if (b->buttonsDown>= 1&&  !--b->buttonsDown)
>> -	    b->motionMask = 0;
>> -	if (b->map[key]<= 5)
>> -	    b->state&= ~((Button1Mask>>  1)<<  b->map[key]);
>>
>> +        DecreaseButtonCount(device, key,&b->buttonsDown,&b->motionMask,&b->state);
>>           UpdateDeviceMotionMask(device,  b->state, b->motionMask);
>>       } else if (event->type == ET_ProximityIn)
>>   	device->proximity->in_proximity = TRUE;
>
> Why not just pass a pointer to the button class instead of pointers to
> three fields of the button class?

ah, yeah, I can see how that wouldn't make sense without seeing the 
follow-up. the TouchClassRec likewise has buttonsDown, state, motionMask 
so that function is called for both ButtonPress/Release as well as 
TouchBegin/End with different parameters. Passing the button class in 
would require the touch class to be partially binary compatible. This 
way is easier, imo

Cheers,
   Peter