nixpkgs/pkgs/applications/graphics/sane/config.nix
Symphorien Gibol c64fb5000b nixos/sane: allow to disable enabled-by-default plugins
use case: disabling v4l plugin because I don't use my webcam as a
scanner.
2021-02-19 16:52:26 +01:00

54 lines
1.7 KiB
Nix

{ lib, stdenv }:
{ paths, disabledDefaultBackends ? [] }:
with lib;
let
installSanePath = path: ''
if [ -e "${path}/lib/sane" ]; then
find "${path}/lib/sane" -maxdepth 1 -not -type d | while read backend; do
symlink "$backend" "$out/lib/sane/$(basename "$backend")"
done
fi
if [ -e "${path}/etc/sane.d" ]; then
find "${path}/etc/sane.d" -maxdepth 1 -not -type d | while read conf; do
name="$(basename $conf)"
if [ "$name" = "dll.conf" ] || [ "$name" = "saned.conf" ] || [ "$name" = "net.conf" ]; then
cat "$conf" >> "$out/etc/sane.d/$name"
else
symlink "$conf" "$out/etc/sane.d/$name"
fi
done
fi
if [ -e "${path}/etc/sane.d/dll.d" ]; then
find "${path}/etc/sane.d/dll.d" -maxdepth 1 -not -type d | while read conf; do
symlink "$conf" "$out/etc/sane.d/dll.d/$(basename $conf)"
done
fi
'';
disableBackend = backend: ''
grep -q '${backend}' $out/etc/sane.d/dll.conf || { echo '${backend} is not a default plugin in $SANE_CONFIG_DIR/dll.conf'; exit 1; }
substituteInPlace $out/etc/sane.d/dll.conf --replace '${backend}' '# ${backend} disabled in nixos config'
'';
in
stdenv.mkDerivation {
name = "sane-config";
phases = "installPhase";
installPhase = ''
function symlink () {
local target=$1 linkname=$2
if [ -e "$linkname" ]; then
echo "warning: conflict for $linkname. Overriding $(readlink $linkname) with $target."
fi
ln -sfn "$target" "$linkname"
}
mkdir -p $out/etc/sane.d $out/etc/sane.d/dll.d $out/lib/sane
''
+ (concatMapStrings installSanePath paths)
+ (concatMapStrings disableBackend disabledDefaultBackends);
}