[Xcb] python generator again

[Thomas Hunger]

Hello,

reading Jameys last post (thanks Jamey!) showed me that I had some 
wrong ideas in my head, so I started over again. The new version 
generates code which compiles and works for simple examples. Checking 
for symbols says that XSL and Python generate the same 
function-symbols. 

What I am missing is a way to compare if both APIs (XSL-generated and 
Python-generated) are exactly the same (i.e. do all functions have 
the same signature). Does anyone know how to do this?

Anyway, the new code can be accessed like this:

$ git remote add htom git://htom.de/libxcb.git
$ git fetch htom
$ git checkout -b pygen refs/remotes/htom/pygen

= Brief technical overview =

The generator works in 3 major steps:

1) reading the XML description and building a Tree of 
   objects in parallel. Elements that are references later on
   via a ref="" or type="" are registered in a type-registry.

2) A fill() function fills out implicit fields. E.g. the "length"
   member in request which is not given explicitly in the
   description. It also resolves type="" and ref="" references.

3) A generate function outputs all neccessary code. It uses some 
   helper functions to generate more complex functions like e.g.
   the request implementations.

A lot of the variable names are quite bad (e.g. fill()) and unclear. I 
will improve on this.

Unfortunally I already know of two major changes which I need to 
implement at least parts of the server side XCB.

Tom