Move escapeSystemdPath to lib/utils.nix

The new file ‘utils.nix’ is intended for NixOS-specific library
functions (i.e. stuff that shouldn't go into Nixpkgs' lib/).

1 files changed, 10 insertions, 0 deletions

diff --git a/lib/utils.nix b/lib/utils.nix
new file mode 100644
index 00000000000..b75e063eaa9
--- /dev/null
+++ b/lib/utils.nix
@@ -0,0 +1,10 @@
+pkgs: with pkgs.lib;
+
+rec {
+
+  # Escape a path according to the systemd rules, e.g. /dev/xyzzy
+  # becomes dev-xyzzy.  FIXME: slow.
+  escapeSystemdPath = s:
+   replaceChars ["/" "-"] ["-" "\\x2d"] (substring 1 (stringLength s) s);
+
+}