nixpkgs/nixos/lib/utils.nix

28 lines
1 KiB
Nix

pkgs: with pkgs.lib;
rec {
# Check whenever fileSystem is needed for boot
fsNeededForBoot = fs: fs.neededForBoot
|| elem fs.mountPoint [ "/" "/nix" "/nix/store" "/var" "/var/log" "/var/lib" "/etc" ];
# Check whenever `b` depends on `a` as a fileSystem
# FIXME: it's incorrect to simply use hasPrefix here: "/dev/a" is not a parent of "/dev/ab"
fsBefore = a: b: ((any (x: elem x [ "bind" "move" ]) b.options) && (a.mountPoint == b.device))
|| (hasPrefix a.mountPoint b.mountPoint);
# Escape a path according to the systemd rules, e.g. /dev/xyzzy
# becomes dev-xyzzy. FIXME: slow.
escapeSystemdPath = s:
replaceChars ["/" "-" " "] ["-" "\\x2d" "\\x20"]
(if hasPrefix "/" s then substring 1 (stringLength s) s else s);
# Returns a system path for a given shell package
toShellPath = shell:
if types.shellPackage.check shell then
"/run/current-system/sw${shell.shellPath}"
else if types.package.check shell then
throw "${shell} is not a shell package"
else
shell;
}