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|
#! @shell@ -e
# Allow the location of NixOS sources and the system configuration
# file to be overridden.
: ${mountPoint=/mnt}
: ${NIXOS_CONFIG=/etc/nixos/configuration.nix}
export NIXOS_CONFIG
usage () {
echo 1>&2 "
Usage: $0 [-v] [-d] [-l] [--xml] OPTION_NAME
$0 --install
This program allows you to inspect the current value of NixOS
configuration options. It can also generate a basic NixOS
configuration file.
Options:
-i | --install Write a template NixOS configuration file to
${mountPoint:+$mountPoint/}$NIXOS_CONFIG.
-v | --value Display the current value, based on your
configuration.
-d | --description Display the default value, the example and the
description.
-l | --lookup Display where the option is defined and where it
is declared.
--xml Print an XML representation of the result.
Implies -vdl options.
--help Show this message.
Environment variables affecting $0:
\$mountPoint Path to the target file system.
\$NIXOS_CONFIG Path to your configuration file.
"
exit 1;
}
#####################
# Process Arguments #
#####################
desc=false
defs=false
value=false
xml=false
install=false
verbose=false
option=""
argfun=""
for arg; do
if test -z "$argfun"; then
case $arg in
-*)
longarg=""
sarg="$arg"
while test "$sarg" != "-"; do
case $sarg in
--*) longarg=$arg; sarg="--";;
-d*) longarg="$longarg --description";;
-v*) longarg="$longarg --value";;
-l*) longarg="$longarg --lookup";;
-i*) longarg="$longarg --install";;
-*) usage;;
esac
# remove the first letter option
sarg="-${sarg#??}"
done
;;
*) longarg=$arg;;
esac
for larg in $longarg; do
case $larg in
--description) desc=true;;
--value) value=true;;
--lookup) defs=true;;
--xml) xml=true;;
--install) install=true;;
--verbose) verbose=true;;
--help) usage;;
-*) usage;;
*) if test -z "$option"; then
option="$larg"
else
usage
fi;;
esac
done
else
case $argfun in
set_*)
var=$(echo $argfun | sed 's,^set_,,')
eval $var=$arg
;;
esac
argfun=""
fi
done
if $xml; then
value=true
desc=true
defs=true
fi
# --install cannot be used with -d -v -l without option name.
if $value || $desc || $defs && $install && test -z "$option"; then
usage
fi
generate=false
if ! $defs && ! $desc && ! $value && $install && test -z "$option"; then
generate=true
fi
if ! $defs && ! $desc; then
value=true
fi
if $verbose; then
set -x
else
set +x
fi
#############################
# Process the configuration #
#############################
evalNix(){
nix-instantiate - --eval-only "$@"
}
evalAttr(){
local prefix=$1
local suffix=$2
local strict=$3
echo "(import <nixos> {}).$prefix${option:+.$option}${suffix:+.$suffix}" |
evalNix ${strict:+--strict}
}
evalOpt(){
evalAttr "eval.options" "$@"
}
evalCfg(){
evalAttr "config" "$@"
}
findSources(){
local suffix=$1
echo "builtins.map (f: f.source) (import <nixos> {}).eval.options${option:+.$option}.$suffix" |
evalNix --strict
}
# Given a result from nix-instantiate, recover the list of attributes it
# contains.
attrNames() {
local attributeset=$1
# sed is used to replace un-printable subset by 0s, and to remove most of
# the inner-attribute set, which reduce the likelyhood to encounter badly
# pre-processed input.
echo "builtins.attrNames $attributeset" | \
sed 's,<[A-Z]*>,0,g; :inner; s/{[^\{\}]*};/0;/g; t inner;' | \
evalNix --strict
}
# map a simple list which contains strings or paths.
nixMap() {
local fun="$1"
local list="$2"
local elem
for elem in $list; do
test $elem = '[' -o $elem = ']' && continue;
$fun $elem
done
}
if $install; then
NIXOS_CONFIG="$mountPoint$NIXOS_CONFIG"
fi
if $generate; then
mkdir -p $(dirname "$NIXOS_CONFIG")
# Scan the hardware and add the result to /etc/nixos/hardware-scan.nix.
hardware_config="${NIXOS_CONFIG%/configuration.nix}/hardware-configuration.nix"
if test -e "$hardware_config"; then
echo "A hardware configuration file exists, generation skipped."
else
echo "Generating a hardware configuration file in $hardware_config..."
nixos-hardware-scan > "$hardware_config"
fi
if test -e "$NIXOS_CONFIG"; then
echo 1>&2 "error: Cannot generate a template configuration because a configuration file exists."
exit 1
fi
nl="
"
if test -e /sys/firmware/efi/efivars; then
l1=" # Use the gummiboot efi boot loader."
l2=" boot.loader.grub.enable = false;"
l3=" boot.loader.gummiboot.enable = true;"
l4=" boot.loader.efi.canTouchEfiVariables = true;"
# !!! Remove me when nixos is on 3.10 or greater by default
l5=" # EFI booting requires kernel >= 3.10"
l6=" boot.kernelPackages = pkgs.linuxPackages_3_10;"
bootloader_config="$l1$nl$l2$nl$l3$nl$l4$nl$nl$l5$nl$l6"
else
l1=" # Use the Grub2 boot loader."
l2=" boot.loader.grub.enable = true;"
l3=" boot.loader.grub.version = 2;"
l4=" # Define on which hard drive you want to install Grub."
l5=' # boot.loader.grub.device = "/dev/sda";'
bootloader_config="$l1$nl$l2$nl$l3$nl$nl$l4$nl$l5"
fi
echo "Generating a basic configuration file in $NIXOS_CONFIG..."
# Generate a template configuration file where the user has to
# fill the gaps.
cat <<EOF > "$NIXOS_CONFIG"
# Edit this configuration file to define what should be installed on
# the system. Help is available in the configuration.nix(5) man page
# or the NixOS manual available on virtual console 8 (Alt+F8).
{ config, pkgs, ... }:
{
imports =
[ # Include the results of the hardware scan.
./hardware-configuration.nix
];
boot.initrd.kernelModules =
[ # Specify all kernel modules that are necessary for mounting the root
# filesystem.
# "xfs" "ata_piix"
# fbcon # Uncomment this when EFI booting to see the console before the root partition is mounted
];
$bootloader_config
# networking.hostName = "nixos"; # Define your hostname.
# networking.wireless.enable = true; # Enables Wireless.
# Add filesystem entries for each partition that you want to see
# mounted at boot time. This should include at least the root
# filesystem.
# fileSystems."/".device = "/dev/disk/by-label/nixos";
# fileSystems."/data" = # where you want to mount the device
# { device = "/dev/sdb"; # the device
# fsType = "ext3"; # the type of the partition
# options = "data=journal";
# };
# List swap partitions activated at boot time.
swapDevices =
[ # { device = "/dev/disk/by-label/swap"; }
];
# Select internationalisation properties.
# i18n = {
# consoleFont = "lat9w-16";
# consoleKeyMap = "us";
# defaultLocale = "en_US.UTF-8";
# };
# List services that you want to enable:
# Enable the OpenSSH daemon.
# services.openssh.enable = true;
# Enable CUPS to print documents.
# services.printing.enable = true;
# Enable the X11 windowing system.
# services.xserver.enable = true;
# services.xserver.layout = "us";
# services.xserver.xkbOptions = "eurosign:e";
# Enable the KDE Desktop Environment.
# services.xserver.displayManager.kdm.enable = true;
# services.xserver.desktopManager.kde4.enable = true;
}
EOF
exit 0
fi;
# This duplicates the work made below, but it is useful for processing
# the output of nixos-option with other tools such as nixos-gui.
if $xml; then
evalNix --xml --no-location <<EOF
let
reach = attrs: attrs${option:+.$option};
nixos = import <nixos> {};
nixpkgs = import <nixpkgs> {};
sources = builtins.map (f: f.source);
opt = reach nixos.eval.options;
cfg = reach nixos.config;
in
with nixpkgs.lib;
let
optStrict = v:
let
traverse = x :
if isAttrs x then
if x ? outPath then true
else all id (mapAttrsFlatten (n: traverseNoAttrs) x)
else traverseNoAttrs x;
traverseNoAttrs = x:
# do not continue in attribute sets
if isAttrs x then true
else if isList x then all id (map traverse x)
else true;
in assert traverse v; v;
in
if isOption opt then
optStrict ({}
// optionalAttrs (opt ? default) { inherit (opt) default; }
// optionalAttrs (opt ? example) { inherit (opt) example; }
// optionalAttrs (opt ? description) { inherit (opt) description; }
// optionalAttrs (opt ? type) { typename = opt.type.name; }
// optionalAttrs (opt ? options) { inherit (opt) options; }
// {
# to disambiguate the xml output.
_isOption = true;
declarations = sources opt.declarations;
definitions = sources opt.definitions;
value = cfg;
})
else
opt
EOF
exit $?
fi
if test "$(evalOpt "_type" 2> /dev/null)" = '"option"'; then
$value && evalCfg;
if $desc; then
$value && echo;
if default=$(evalOpt "default" - 2> /dev/null); then
echo "Default: $default"
else
echo "Default: <None>"
fi
if example=$(evalOpt "example" - 2> /dev/null); then
echo "Example: $example"
fi
echo "Description:"
eval printf $(evalOpt "description")
fi
if $defs; then
$desc || $value && echo;
printPath () { echo " $1"; }
echo "Declared by:"
nixMap printPath "$(findSources "declarations")"
echo ""
echo "Defined by:"
nixMap printPath "$(findSources "definitions")"
echo ""
fi
else
# echo 1>&2 "Warning: This value is not an option."
result=$(evalCfg)
if names=$(attrNames "$result" 2> /dev/null); then
echo 1>&2 "This attribute set contains:"
escapeQuotes () { eval echo "$1"; }
nixMap escapeQuotes "$names"
else
echo 1>&2 "An error occured while looking for attribute names."
echo $result
fi
fi
|