How the scancode convert to x keycode/keysym

[Pang Dawei]

Hi,there,
   Could you give me some idea about how the scancode convert to X
keycode/keysum?
   For example, the scancode of WIN key is the e05b, I use the xev to
test the same key, the xev showed the keycode is 115.
I want to know what the algorithm to convert from the 5b to 115 and
what part of Xorg source code is related to the algorithm.
Thank you very much.

-- 
--Pang Dawei