fillDiskWithDebs: Create fake start-stop-daemon.

This is needed in order to prevent services from starting while
populating the image with the contents of the .deb files. The procedure
used here is exactly the same as used in debootstrap.

Signed-off-by: aszlig <aszlig@redmoonstudios.org>

pkgs/build-support/vm/default.nix

@@ -599,8 +599,17 @@ rec {
             debs="$debs /inst/$i";
           done
           chroot=$(type -tP chroot)
+
+          # Create a fake start-stop-daemon script, as done in debootstrap.
+          mv "/mnt/sbin/start-stop-daemon" "/mnt/sbin/start-stop-daemon.REAL"
+          echo "#!/bin/true" > "/mnt/sbin/start-stop-daemon"
+          chmod 755 "/mnt/sbin/start-stop-daemon"
+
           PATH=/usr/bin:/bin:/usr/sbin:/sbin $chroot /mnt \
             /usr/bin/dpkg --install --force-all $debs < /dev/null || true
+
+          # Move the real start-stop-daemon back into its place.
+          mv "/mnt/sbin/start-stop-daemon.REAL" "/mnt/sbin/start-stop-daemon"
         done
 
         echo "running post-install script..."