core/pkgs/by-name/db/dbus/make-dbus-conf.nix

{ runCommand, writeText, libxslt, dbus, findXMLCatalogs
, serviceDirectories ? [ ]
, suidHelper ? "/var/setuid-wrappers/dbus-daemon-launch-helper"
, apparmor ? "disabled" # one of enabled, disabled, required
}:

# DBus has two configuration parsers -- normal and "trivial", which is used
# for suid helper. Unfortunately the latter doesn't support <include>
# directive. That means that we can't just place our configuration to
# *-local.conf -- it needs to be in the main configuration file.
runCommand "dbus-1" {
  inherit serviceDirectories suidHelper apparmor;
  preferLocalBuild = true;
  allowSubstitutes = false;

  nativeBuildInputs = [ libxslt.bin findXMLCatalogs ];

  buildInputs = [ dbus.out ];
} ''
  mkdir -p $out

  xsltproc --nonet \
    --stringparam serviceDirectories "$serviceDirectories" \
    --stringparam suidHelper "$suidHelper" \
    --stringparam apparmor "$apparmor" \
    ${./make-system-conf.xsl} ${dbus}/share/dbus-1/system.conf \
    > $out/system.conf
  xsltproc --nonet \
    --stringparam serviceDirectories "$serviceDirectories" \
    --stringparam apparmor "$apparmor" \
    ${./make-session-conf.xsl} ${dbus}/share/dbus-1/session.conf \
    > $out/session.conf

  # check if files are empty or only contain space characters
  grep -q '[^[:space:]]' "$out/system.conf" || (echo "\"$out/system.conf\" was generated incorrectly and is empty, try building again." && exit 1)
  grep -q '[^[:space:]]' "$out/session.conf" || (echo "\"$out/session.conf\" was generated incorrectly and is empty, try building again." && exit 1)
''