shell glue for configuration of bgimage, colors, superusers, and passwords via /etc/default/grub

[debian]

hi!

i'm sorry but i'm not sure what files in my /etc/grub.d/ are 
distribution-specific, so (some (parts) of) these might be specific. i guess it 
might still help for some copy+paste. it's nothing special anyway, i'm just 
submitting this here because obviously nobody else has done so yet and it might 
have the potential to save somebody some typing work. :)
you can find all the new variable names for /etc/default/grub at the end of the 
grub-mkconfig diff (last diff).
what should be noted is that $ in md5 crypt strings (GRUB_PASSWORD_*) have to 
be escaped with a \.

to add the superusers with passwords from /etc/default/grub:
----- snip -----
--- /etc/grub.d.orig/00_header  2009-11-02 19:44:07.000000000 +0100
+++ /etc/grub.d/00_header       2009-11-02 19:21:03.000000000 +0100
@@ -39,6 +39,18 @@ cat << EOF
set default=${GRUB_DEFAULT}
EOF

+if [ "x${GRUB_SUPERUSERS}" != "x" ] ; then
+       cat << EOF
+set superusers="${GRUB_SUPERUSERS}"
+EOF
+       for i in ${GRUB_SUPERUSERS}; do
+               eval "GRUB_PASSWORD=\$GRUB_PASSWORD_$i"
+               cat << EOF
+password ${i} ${GRUB_PASSWORD}
+EOF
+       done
+fi
+
case ${GRUB_TERMINAL_INPUT}:${GRUB_TERMINAL_OUTPUT} in
  serial:* | *:serial)
    if ! test -e ${grub_prefix}/serial.mod ; then
----- snap -----

to use image and color config from /etc/default/grub:
----- snip -----
--- /etc/grub.d.orig/05_debian_theme    2009-09-28 18:47:32.000000000 +0200
+++ /etc/grub.d/05_debian_theme 2009-09-28 20:22:17.000000000 +0200
@@ -5,30 +5,46 @@ source /usr/lib/grub/grub-mkconfig_lib
set_blue_theme()
{
  cat << EOF
-set menu_color_normal=cyan/blue
-set menu_color_highlight=white/blue
+set menu_color_normal=$GRUB_MENU_COLOR_NORMAL
+set menu_color_highlight=$GRUB_MENU_COLOR_HIGHLIGHT
EOF
}

+# set menu colors if unset
+if test -z "$GRUB_MENU_COLOR_NORMAL"; then
+       GRUB_MENU_COLOR_NORMAL="cyan/blue"
+fi
+if test -z "$GRUB_MENU_COLOR_HIGHLIGHT"; then
+       GRUB_MENU_COLOR_HIGHLIGHT="white/blue"
+fi
+if test -z "$GRUB_COLOR_NORMAL"; then
+       GRUB_COLOR_NORMAL="black/black"
+fi
+if test -z "$GRUB_COLOR_HIGHLIGHT"; then
+       GRUB_COLOR_HIGHLIGHT="magenta/black"
+fi
+
# check for usable backgrounds
use_bg=false
-if [ "$GRUB_TERMINAL_OUTPUT" = "gfxterm" ] ; then
-  for i in 
{/boot/grub,/usr/share/images/desktop-base}/moreblue-orbit-grub.{png,tga} ; do
-    if is_path_readable_by_grub $i ; then 
-      bg=$i
-      case ${bg} in
-        *.png)         reader=png ;;
-        *.tga)         reader=tga ;;
-        *.jpg|*.jpeg)  reader=jpeg ;;
-      esac
-      if test -e /boot/grub/${reader}.mod ; then
-        echo "Found Debian background: `basename ${bg}`" >&2
-        use_bg=true
-        break
+for f in $GRUB_BACKGROUND_IMAGE moreblue-orbit-grub; do
+  if [ "$GRUB_TERMINAL_OUTPUT" = "gfxterm" ] ; then
+    for i in {/boot/grub,/usr/share/images/desktop-base}/$f.{png,tga} ; do
+      if is_path_readable_by_grub $i ; then 
+        bg=$i
+        case ${bg} in
+          *.png)               reader=png ;;
+          *.tga)               reader=tga ;;
+          *.jpg|*.jpeg)        reader=jpeg ;;
+        esac
+        if test -e /boot/grub/${reader}.mod ; then
+          echo "Found Debian background: `basename ${bg}`" >&2
+          use_bg=true
+          break 2
+        fi
      fi
-    fi
-  done
-fi
+    done
+  fi
+done

# set the background if possible
if ${use_bg} ; then
@@ -36,8 +52,8 @@ if ${use_bg} ; then
  cat << EOF
insmod ${reader}
if background_image `make_system_path_relative_to_its_root ${bg}` ; then
-  set color_normal=black/black
-  set color_highlight=magenta/black
+  set color_normal=$GRUB_COLOR_NORMAL
+  set color_highlight=$GRUB_COLOR_HIGHLIGHT
else
EOF
fi
----- snap -----

to make all of the above work with grub-mkconfig:
----- snip -----
--- /usr/sbin/grub-mkconfig.orig        2009-09-28 18:40:53.000000000 +0200
+++ /usr/sbin/grub-mkconfig     2009-11-02 19:14:08.000000000 +0100
@@ -224,7 +224,16 @@ export GRUB_DEFAULT \
  GRUB_DISABLE_LINUX_UUID \
  GRUB_DISABLE_LINUX_RECOVERY \
  GRUB_GFXMODE \
-  GRUB_DISABLE_OS_PROBER
+  GRUB_BACKGROUND_IMAGE \
+  GRUB_COLOR_NORMAL \
+  GRUB_COLOR_HIGHLIGHT \
+  GRUB_MENU_COLOR_NORMAL \
+  GRUB_MENU_COLOR_HIGHLIGHT \
+  GRUB_DISABLE_OS_PROBER \
+  GRUB_SUPERUSERS
+for i in ${GRUB_SUPERUSERS}; do
+  export GRUB_PASSWORD_$i
+done

if test "x${grub_cfg}" != "x"; then
  rm -f ${grub_cfg}.new
----- snap -----

i don't quite understand the color syntax. i didn't manage yet e.g. to set the 
text foreground color without a text background color (to prevent wiping the 
background image with the text background color)... hints very welcome.

regards,

        Chris