[Nix-dev] using my own xorg.conf

[James Cook]

Hi nix-dev,

I'm planning to write a simple NixOS patch that optionally makes the
default contents of xorg.conf empty, but I wanted to see what people
think about it first.

NixOS currently generates an xorg.conf file based on various options
services.xserver.*.  Unfortunately these options are not quite
flexible enough to support my preferred configuration[0]. For the past
few months, I've gotten around this by doing two things:

0. Add "services.xserver.config = builtins.readFile ./xorg.conf;" to
configuration.nix (referring to my own xorg.conf)
1. Patch modules/services/x11/xserver.nix to remove
"services.xserver.config = '' ... ''". If I don't do this, then the
resulting x.org configuration consists of the default configuration
concatenated with my configuration.

I would prefer to replace step 1 with something simple like:
1. set "services.xserver.generateConfig = false;" in configuration.nix

I'm happy to write the patch myself (should be esay) but I wanted to
check first to see if anyone would prefer a different change.

(Note: My change doesn't remove the automatically generated font or
module paths; the buildCommand adds those itself. The parts I need to
turn off are the ServerLayout, Monitor, Device and Screen sections.)

Thanks,
  James

[0] My xorg.conf is at http://pastebin.com/Qb0sDA6W . Summary: two
monitors, one of them rotated; nvidia proprietary driver. To
accomplish this I have two "Device" sections and two "Screen"
sections.  NixOS only wants to generate one device section per driver.