From fd2047c642ba44d5c300149f63f68c34da773c04 Mon Sep 17 00:00:00 2001
From: Julian Stecklina <js@alien8.de>
Date: Sat, 25 Jul 2020 16:46:08 +0200
Subject: [PATCH] nixos/lib/make-ext4-fs: fix after mkfs.ext4 refactoring

In 9ac1ab10c963a86457c2c9b1edf31542ff3737cd this library function was
refactored to use mkfs.ext4 instead of cptofs. There are two problems:

If populateImageCommands would create no files (which is fine), a cp
invocation would fail due to missing source arguments.

Another problem is that mkfs.ext4 relies on fakeroot to have sane
uid/gids in the generated filesystem image. This currently doesn't
work for cross compiling.
---
 nixos/lib/make-ext4-fs.nix | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/nixos/lib/make-ext4-fs.nix b/nixos/lib/make-ext4-fs.nix
index 74a6c134e64..33dbc8f5ec4 100644
--- a/nixos/lib/make-ext4-fs.nix
+++ b/nixos/lib/make-ext4-fs.nix
@@ -46,7 +46,10 @@ pkgs.stdenv.mkDerivation {
       (
         GLOBIGNORE=".:.."
         shopt -u dotglob
-        cp -a --reflink=auto ./files/* -t ./rootImage/
+
+        for f in ./files/*; do
+            cp -a --reflink=auto -t ./rootImage/ "$f"
+        done
       )
 
       # Also include a manifest of the closures in a format suitable for nix-store --load-db