README

This is zen, the Hackable X server.

In just 5500 lines of Common Lisp.



INSTRUCTIONS : 

You will need :
Linux.
A decent OpenGL driver, and therefore, unfortunately, a running X server :)    (to create a GLX context)
SBCL with cl-opengl, CFFI, CLX, Skippy, CL-PPCRE, bordeaux-threads

Starting zen :

1) Identify the mouse and keyboard devices /dev/input/event<n> by reading /proc/bus/input/devices. Modify your input-devices.lisp accordingly.
2) sudo chmod ugo+r /dev/input/*
3) In SBCL , (compile-file "data/keys") 
4) Load "start.lisp" in sbcl
5) (start)
... and if (when) you crash :
6) (rst)

Testing apps : in a terminal,
export DISPLAY=127.0.0.1:3
Then start your app.



FUN WITH ZEN

The 3 most interesting/fun things to hack on right now are :

- Optimization. The low hanging fruit is here for you to pick up :) 

  (require 'sb-sprof)
  (sb-sprof:start-profiling :sample-interval 0.001 :threads :all :sampling t))
  <run a slow app>
  (sb-sprof:stop-profiling)
  (sb-sprof:report)	
  <see what happens>

- Simplifying : zen could definitely become even leaner than it is now.

- XRender implementation
  (but potentially a big job)

[Of course, there are also a large number of work items to turn zen into a 'production server', but that was never the point ! ]


LIMITATIONS

You will notice that zen is quite slow and buggy. Please feel free to report : zen crashes, and app crashes/exits that could be caused by X protocol bugs. 

Most noticeable issing features :
- All kinds of grabs
- Various old fashioned rendering requests : CopyPlanes ; Arcs, and more
- Most GC fields are ignored 
- see also a whole section of unimplemented requests.



* The bad (do not read this code !) :

Font support : no use improving on this, as modern apps render them client-side anyway.
SW cursor : no use improving on this either, this is a hack that wouldn't belong in a production server.


CONTACT

baccou@normalesup.org


All the files in this package are (c) 2011 Pierre-Yves Baccou, unless specified otherwise.