infodir="usr/share/info"
filelist=('grub.info' 'grub-dev.info')

grub_pre_configure() {
  grub_cfg="/boot/grub/grub.cfg"

  cat << 'EOM'
Generating grub.cfg.auto config file...
This may fail on some machines running a custom kernel.
EOM
  no_auto=
  grub-mkconfig -o $grub_cfg.auto && echo "done." || no_auto=1

  if [ ! -f $grub_cfg ] ; then
   if [ -f $grub_cfg.pacsave ]; then
     echo "Copying $grub_cfg.pacsave to $grub_cfg"
     cp -p $grub_cfg.pacsave $grub_cfg
   elif [ -f $grub_cfg.auto -a -z "$no_auto" ] ; then
     echo "Copying $grub_cfg.auto to $grub_cfg"
     install -D -m0644 $grub_cfg.auto $grub_cfg
   else
     echo "Copying $grub_cfg.default to $grub_cfg"
     install -D -m0644 $grub_cfg.default $grub_cfg
   fi
  fi
}

post_install() {
  grub_pre_configure
  for file in ${filelist[@]}; do
    install-info ${infodir}/${file}.gz ${infodir}/dir 2> /dev/null
  done
}

post_upgrade() {
  grub_pre_configure
  for file in ${filelist[@]}; do
    install-info ${infodir}/${file}.gz ${infodir}/dir 2> /dev/null
  done
}

pre_remove() {
  for file in ${filelist[@]}; do
    install-info --delete ${infodir}/${file} ${infodir}/dir 2> /dev/null
  done
}