TODO : Add more --disable-FOO...

[Thierry Laronde]

Hello,

I'm looking for creation of floppies (for a project, and for
debian-installer), so I tried to reduce the size of stage2.

This is an entry in the TODO list :

  
* Add more --disable-FOO options to configure, so that you can create a
  minimum GRUB image. This is useful for boot floppies because of the size
  restriction. !

So are you agreing with this kind of way :

Using defines (with builtins functions), one can achieve some high
flexibility on compile time. But, for basic usages, this is unpractical. So
we can group via --disable-<package> several functions that belong to the
same group. 

What kind of groups can we see ? At my first sight (the lists are not
exhaustive !):

o Boot functions : chainloader, kernel, module, moduleunzip, initrd, boot

o "devices" functions : [fs], [netboot], serial,...

o install functions : install, setup, embed

o debug functions : debug, fstest, impsprobe, ioprobe, read, testload,
testvbe, uppermem, vbeprobe, displaymem

o customisation functions : color, setkey, password, configfile, ifconfig

o "sugar" functions : find

The first category are, for me, the core grub : a bootloader must be able to
boot... So I don't imagine to offer an option to disable the whole bunch (and
I don't think that to be able to not compile one of them is really
necessary).

The second type depends, partially, on material needs.

The third type is, strictly speaking, not necessary for booting. We can
provide an option to not compile installation functions. But one need to
have another "extended" GRUB to install this one, or to dd and patch by hand
the files.

The fourth can be disabled if needed.

The fifth and the sixth are arguable.

So, question : do you think that adding the #ifdef <NAME>_FUNC / #endif for
all the functions that are not core boot ones, and adding 4 or 5 "packages"
options in configure is the good way to go ?

Please note that the gain is not really spectacular. Disabling a lot of
things (but not all that can be disabled), I have gained 20 Ko. It's 25% of
the size.

TIA
-- 
Thierry LARONDE, Centre de Ressources Informatiques, Archamps - France
http://www.cri74.org
PingOO, serveur de com sur distribution GNU/Linux: http://www.pingoo.org