Archive for May, 2008

fakemouse — a driver that emulates a mouse

May 27, 2008

For my SoC project I need some mechanism to evaluate the improvement of the input thread inside X. So I wrote a simple kernel driver that emulates the mouse device moving and emitting bits of a simple pattern. I don’t know if something like this already exists or if there are other ways to do it, but the fact is that the solution I thought took me only few hours between the moment that I imagined, collected some ideas on the Web and implemented it.

Why emulate a device? I need stress the X server always with same routines and things like XWarpPointer() and XTestFake*MotionEvent() is not close to a real user usage because they do not pass through all the paths of the event creation stage inside X. So now I can run fakemouse module together with some x11perf test and collect the results comparing the X with and without input thread. Cool :)

For those who are interested in the driver can do the following:
# wget
# tar xzvf fakemouse-0.01.tar.gz
# cd fakemouse-0.01
# make
# insmod fakemouse.ko
# echo 1 > /sys/module/fakemouse/parameters/mouseon

and be happy seeing what happens in some event node create by fakemouse (/dev/input/event*).