Demi Marie Obenour <demiobenour@gmail.com> writes:

> Due to a systemd bug [1], building systemd-sysupdate does not require
> that systemd-pull is built as well.  However, systemd-sysupdate has a
> run-time dependency on systemd-pull.  Therefore, override the systemd
> derivation so that systemd-pull is built.  Confusingly, this requires
> enabling systemd-importd.
>
> If systemd-pull or systemd-sysupdate is not built, the resulting image
> will be broken and users will not be able to recover without either a
> reinstall or reverting to the previous version.  Therefore, add a check
> to ensure that both are in fact built.  Use 'cat' rather than just
> 'stat' to catch broken symlinks and the like.
>
> Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
> ---
>  host/rootfs/default.nix | 23 +++++++++++++++++++++--
>  1 file changed, 21 insertions(+), 2 deletions(-)
>
> diff --git a/host/rootfs/default.nix b/host/rootfs/default.nix
> index aea2e46bb5998176eb6d9b8aef802ae270fdd28c..c2045ad96cca37a1bf1a7b82aa35a583cc5aee93 100644
> --- a/host/rootfs/default.nix
> +++ b/host/rootfs/default.nix
> @@ -43,7 +43,8 @@ let
>      })
>  
>    # Take kmod from pkgsGui since we use pkgsGui.kmod.lib below anyway.
> -  ] ++ (with pkgsGui; [ cosmic-files crosvm foot fuse3 kmod systemd ]);
> +  ] ++ (with pkgsGui; [ cosmic-files crosvm foot fuse3 kmod ]);
> +
>  
>    nixosAllHardware = nixos ({ modulesPath, ... }: {
>      imports = [ (modulesPath + "/profiles/all-hardware.nix") ];
> @@ -64,7 +65,15 @@ let
>    # https://inbox.vuxu.org/musl/20251017-dlopen-use-rpath-of-caller-dso-v1-1-46c69eda1473@iscas.ac.cn/
>    usrPackages = [
>      appvm kernel.modules firmware netvm
> -  ] ++ (with pkgsGui; [ dejavu_fonts kmod.lib mesa westonLite ]);
> +  ] ++ (with pkgsGui; [
> +    dejavu_fonts kmod.lib mesa westonLite
> +    # Work around NixOS/nixpkgs#459020: without "withImportd = true"
> +    # systemd-pull doesn't get built, so systemd-sysupdate doesn't work.
> +    (systemd.override {
> +      withImportd = true;
> +      withSysupdate = true;
> +    })
> +  ]);

Let's fix this upstream instead:

https://github.com/NixOS/nixpkgs/pull/461277

>  
>    appvms = {
>      appvm-firefox = callSpectrumPackage ../../vm/app/firefox.nix {};
> @@ -85,6 +94,16 @@ let
>          lndir -ignorelinks -silent "$pkg" "$out/usr"
>      done
>  
> +    # If systemd-pull is missing systemd-sysupdate will fail with a
> +    # very confusing error message.  If systemd-sysupdate doesn't work,
> +    # users will not be able to receive an update that fixes the problem.
> +    for i in sysupdate pull; do
> +        if ! cat -- "$out/usr/lib/systemd/systemd-$i" > /dev/null; then
> +            echo "link to systemd-$i didn't get installed" >&2
> +            exit 1
> +        fi
> +    done
> +
>      # Weston doesn't support SVG icons.
>      inkscape -w 20 -h 20 \
>          -o $out/usr/share/icons/hicolor/20x20/apps/com.system76.CosmicFiles.png \
>

Looks like this will be fixed upstream (as a build error) in the next
systemd release.