Re: RFC: Support Linux command line variants in grub-mkconfig

[Joey Korkames]

> > I think this is growing severely overengineered.  It is already more
> > complex than it needs to be.
> >
> > The scripts in /etc/grub.d *are* config files.  There's no reason you
> > can't edit them to suit your needs.
>
> I agree that my solution does seem rather overengineered.
>
> My problem is that while /etc/grub.d/* may be config files in some 
> technical sense, they don't behave like them.  In particular for most 
> config files, changes you make are largely "orthogonal" to the rest of 
> the file whereas my changes to /etc/grub.d are mixed in with complex 
> logic which I have no interest in changing.  Combined with frequent 
> changes to the default version of the file, this makes merging new 
> versions a burden.
>
> My patch reduces the configuration needed to set up variant command 
> lines to a few lines  in /etc/default/grub, which are indeed orthogonal 
> to the rest of the file.

To solve this exact problem I distribute my own grub.d/01_custom_entries and 
grub.d/40_custom_vars hooks on my systems. They rely on a ruby script that globs 
/boot/vmlinu* (and other operating systems kernels) and builds a hash of 
entries for every kernel and for all the variants of the command line I want 
or need on the systems. Because the entries come first, I can just 
index-count _my_ menu items and know they'll always be "first" and because 
the vars hook is at the end of the mkconfig run, I can "set default=3" from 
there and know it won't be overruled by the stock hooks.

The fact is that this patch would make it seem weird that none of the 
_other_ kernel types in grub.d will have variants either. Leading to a 
proliferation of GRUB_FOOBAROS_VARIANTS= in /etc/default/grub. Bourne 
shell is simply the wrong language for this kind of thing (no 
hashes/dictonaries/multi-dimensional-arrays) but it's all that can be 
demanded by any OS to support grub-mkconfig.

IMHO, the default mkconfig stuff shipped with grub should be considered a 
reference implementation that can be kept simple and working on all 
distros _of_ all OS's but its certainly not the only way to generate a good 
config for your site. Patching the stock system to your specific needs might 
make less burden for you now but more for everyone else down the road.

-joey