Some leftover code from the previously used alloc/free device classes left us
with a incorrect button count. So a button release didn't come through if
a different pointer was moved after the button press.
Rather than freeing/allocing classes each time the device capabilities need to
swap, store them in the devPrivates system.
When a class is unused, it is pushed into the devPrivates, and later recovered
when needed again. This saves us a lot of memory allocations/frees, admittedly
on the cost of some memory.
We don't free the class anymore, so just store the previous pointers, do the
memcpy from the SD and then restore the pointers.
Plugs a memleak too, before xkbInfo was never freed.
Setting it to NULL isn't correct either. The correct behaviour is to realloc
it to the size necessary (or newly alloc it/free it). Otherwise we have a
memleak.
XkbInitIndicatorMap (in XkbInitDevice) calls XkbFindSrvLedInfo. This accesses
the devices kbdfeed struct, which is all nice and dandy if it is NULL. When
copying the device classes however, kbdfeed may not be NULL and thus
XkbFindSrvLedInfo goes on its merry way to do whatever it does.
By copying kbdfeed first, we avoid XkbFSLI to reference the "old" kbdfeed
struct of the previous SD.
Blindly copying will override the focus setting of the master. If there's XI
applications running, they may set the SD focus, while leaving the
MD's focus as it was. In this case, after a class swap we still want to get
the MD's events to the same window as before.
Floating SDs are paired with themselves, so the paired device may not be a
proper keyboard or mouse. Put some extra checks in to avoid dereferencing a
nullpointer later.
Some pointer devices have key classes (e.g. MS Optical Desktop 2000). The
previous test was performed as Error if ptr -> keybd or keybd -> ptr. This
doesnt work with such devices. New test is Succeed if ptr->ptr or
keybd->keybd.
This is a significant shift in how input events are perceived. The common
approach was to treat a core event as a different entity than the XI event.
This could result in the XI event being delivered to a different client than
the core event. This doesn't work nicely if they come from the same device.
Instead, we treat an input event as a single event, that is delivered through
two separate APIs. So when delivering an event, we first try the XI event,
then the core event. If the window want's neither, we go to the parent and
repeat. Once either core or XI has been delivered, the processing stops.
Important: Different to the previous method, if a client registers for core
button events, the parent window will not get XI events. This should only
cause problems when you're mixing core and XI events, so don't do that!
Generic events don't fit into this yet, they cause me headaches.
