Bug#624492: grub-common: allow additional customisation before graphics mode is set

[David Eccles (gringer)]

Package: grub-common
Version: 1.99~rc1-13
Severity: wishlist

I would like to try to get my eeepc 701 to start the grub
menu with a screen resolution of 800x480 (the native
resolution of the computer). This resolution is not
available at grub startup, but various websites suggest
that this resolution can be made available by running
commands that utilise the 915resolution module:

insmod 915resolution
915resolution 5c 800 480 16

I noticed that there is an option that I can put into
/etc/default/grub, 'GRUB_PRELOAD_MODULES', that allows me
to identify modules to be loaded before almost everything
else (lines 32-34 in /etc/grub.d/00_header), but I can't
find anything for additional commands to be run at a
similar stage. While I can fix this by editing 00_header,
that seems to go against the idea of how the grub.d files
are set up.

I can see three possible fixes to this:
1) Add a GRUB_PRELOAD_COMMANDS option to 00_header. This
   may be difficult if it is desirable to protect the
   script from bad code.
2) Split 00_header into two (or more) files. I think the
   header file should really only do basic configuration,
   and other files should do the bulk of the
   configuration.
3) Add code specifically for 915resolution that is parsed
   by 00_default and added to grub.cfg. For example:
   GRUB_915RES_MODES="5c:800x480x16 34:1024x600"

I think the second option is more "Debian", so it is my
preferred option for fixing this bug. My rough proposal
follows:
   00_header: lines 1-77 (until save_env is determined)
   02_display: lines 78-159 (until terminal_output)
   04_themes: remainder (allows 05_debian_theme to work)

My proposal would allow 01_ and 03_ scripts to be put in
for setup before display configuration and theming
respectively.

-- System Information:
Debian Release: wheezy/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing'), (500, 'stable')
Architecture: i386 (i686)

Kernel: Linux 2.6.32-5-686 (SMP w/1 CPU core)
Locale: LANG=en_NZ.UTF-8, LC_CTYPE=en_NZ.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages grub-common depends on:
ii  base-files              6.3              Debian base system miscellaneous f
ii  dpkg                    1.16.0.2         Debian package management system
ii  gettext-base            0.18.1.1-3       GNU Internationalization utilities
ii  install-info            4.13a.dfsg.1-6   Manage installed documentation in
ii  libc6                   2.11.2-11        Embedded GNU C Library: Shared lib
ii  libdevmapper1.02.1      2:1.02.63-3      The Linux Kernel Device Mapper use
ii  libfreetype6            2.4.4-1          FreeType 2 font engine, shared lib
ii  libfuse2                2.8.4-1.4        Filesystem in USErspace library
ii  zlib1g                  1:1.2.3.4.dfsg-3 compression library - runtime

Versions of packages grub-common recommends:
ii  os-prober                     1.46       utility to detect other OSes on a

Versions of packages grub-common suggests:
pn  grub-emu                      <none>     (no description available)
pn  multiboot-doc                 <none>     (no description available)
pn  xorriso                       <none>     (no description available)

-- no debconf information