[gentoo-dev] RC sysinit suggestion

[Simon Reynolds]

Esteemed developers and other Gentoo enthusiasts,

A while back I posted a bug with an updated version crypto-loop to make
encrypted swapspaces pretty simple. I've since thought up a couple of
improvements/safeguards for it, so I should probably revisit it but
that's another matter...
Anyway, at the time, my version of crypto-loop didn't activate the
swap-space for no good reason other than I just thought that that was
what the "Activating Possibly More Swap-Space" in localmount was for.
Well, at some point that stopped working because the baselayout changed
to initialize an undocumented (except for the source) sysinit level.
Since that isn't documented in the rc-script guide I thought that it was
a bit confusing. Also, it is now impossible to say something like
"before localmount".
I had an alternative idea for this though, and was wondering if there
was a good reason against it:

* Add a new command for use in the depends function: "critical"; that
accepts no arguments.
* Eliminate the sysinit runlevel and instead just have /sbin/rc verify
that all scripts marked as critical are running before we consider the
boot level to be started.
* Add a check in depscan.sh that prints a large, red warning if there
is  a critical dependency not currently included in the boot runlevel.

I like this because 1) it re-opens the possibility of having a script in
the boot level that can run before one of the current five critical
dependencies, 2) because it allows dynamic setting of "critical"
scripts, and 3) it also makes the existence and definition of critical
scripts more clear to rc-script hackers like myself.

Even if is deemed a bad idea to remove the sysinit runlevel, I still
think that using the critical flag in the depends module would still be
an improvement over the current method which is just to list them
explicitly in /sbin/rc

Let me know what you think.
~Simon Reynolds

p.s. I'd more than willing to help implement this suggestion.