Without this patch, any negative valuator value is wrong when returned
from XQueryDeviceState(). This is a regression from at least xserver
1.4.
Valuator data is set in dix/getevents.c:set_valuators() by copying
signed int values into an unsigned int field
DeviceEvent.valuators.data.
That data is converted into a double with an implicit cast by
assignment to axisVal[i] in Xi/exevents.c:UpdateDeviceState().
That double is converted back to a signed int in
queryst.c:ProcXQueryDeviceState(). If the original value in
set_valuators() is negative, the double value will be > 2^31 and the
conversion back to a signed int is undefined. (Although I
consistently see the value -2^31.)
Fix this by changing the definition of DeviceEvent.valuators.data from
uint32_t to int32_t.
Signed-off-by: Joe Shaw <joeshaw@litl.com>
Reviewed-by: Chase Douglas <chase.douglas@canonical.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
(cherry picked from commit e354ccac36)
9ae9cbae5f