pyrox.dev
1{ config, lib, pkgs, modules, ... }:
2
3with lib;
4
5let
6
7 # Location of the repository on the harddrive
8 nixosPath = toString ../..;
9
10 # Check if the path is from the NixOS repository
11 isNixOSFile = path:
12 let s = toString path; in
13 removePrefix nixosPath s != s;
14
15 # Copy modules given as extra configuration files. Unfortunately, we
16 # cannot serialized attribute set given in the list of modules (that's why
17 # you should use files).
18 moduleFiles =
19 # FIXME: use typeOf (Nix 1.6.1).
20 filter (x: !isAttrs x && !builtins.isFunction x) modules;
21
22 # Partition module files because between NixOS and non-NixOS files. NixOS
23 # files may change if the repository is updated.
24 partitionedModuleFiles =
25 let p = partition isNixOSFile moduleFiles; in
26 { nixos = p.right; others = p.wrong; };
27
28 # Path transformed to be valid on the installation device. Thus the
29 # device configuration could be rebuild.
30 relocatedModuleFiles =
31 let
32 relocateNixOS = path:
33 "<nixpkgs/nixos" + removePrefix nixosPath (toString path) + ">";
34 relocateOthers = null;
35 in
36 { nixos = map relocateNixOS partitionedModuleFiles.nixos;
37 others = []; # TODO: copy the modules to the install-device repository.
38 };
39
40 # A dummy /etc/nixos/configuration.nix in the booted CD that
41 # rebuilds the CD's configuration (and allows the configuration to
42 # be modified, of course, providing a true live CD). Problem is
43 # that we don't really know how the CD was built - the Nix
44 # expression language doesn't allow us to query the expression being
45 # evaluated. So we'll just hope for the best.
46 configClone = pkgs.writeText "configuration.nix"
47 ''
48 { config, pkgs, ... }:
49
50 {
51 imports = [ ${toString config.installer.cloneConfigIncludes} ];
52 }
53 '';
54
55in
56
57{
58
59 options = {
60
61 installer.cloneConfig = mkOption {
62 default = true;
63 description = ''
64 Try to clone the installation-device configuration by re-using it's
65 profile from the list of imported modules.
66 '';
67 };
68
69 installer.cloneConfigIncludes = mkOption {
70 default = [];
71 example = [ "./nixos/modules/hardware/network/rt73.nix" ];
72 description = ''
73 List of modules used to re-build this installation device profile.
74 '';
75 };
76
77 };
78
79 config = {
80
81 installer.cloneConfigIncludes =
82 relocatedModuleFiles.nixos ++ relocatedModuleFiles.others;
83
84 boot.postBootCommands =
85 ''
86 # Provide a mount point for nixos-install.
87 mkdir -p /mnt
88
89 ${optionalString config.installer.cloneConfig ''
90 # Provide a configuration for the CD/DVD itself, to allow users
91 # to run nixos-rebuild to change the configuration of the
92 # running system on the CD/DVD.
93 if ! [ -e /etc/nixos/configuration.nix ]; then
94 cp ${configClone} /etc/nixos/configuration.nix
95 fi
96 ''}
97 '';
98
99 };
100
101}