This one has been inspired by these guys:

  http://www.informatimago.com/linux/emacs-on-user-mode-linux.html
  https://raymii.org/s/blog/Vim_as_PID_1_Boot_to_Vim.html

It's aimed at building images running their main userspace
piece instead of ramdisk's init, that means PID=1, UID=0.

Mostly fun of course but it suddenly became interesting with
kernel IP autoconfiguration and e.g. elinks running this way
(NB: requires patched make-initrd 0.8.8 at the moment to get
resolver configured).

And startup times are way better than sysvinit and systemd combined!

cfg.in/README should be explicit regarding
"automatic=method:cdrom" being usable for
flash media too (propagator has been fixed
since 20101130-alt10 or so, and gfxboot is
able to tweak the cmdline having figured
out it's running off the flash either).

It's not neccessarily installation media.

Shift boot order so that rescue image can get mediacheck too
but still boot into rescue by default.

As proposed by Maxim Suhanov since there are only
7 loop devices available upon bootup which might be
not enough given ro,loop mounts by default.

This value is used to authenticate rescue rootfs image
by verifying the squashfs file's sha256sum before use
(propagator-20140419+).

Looks like this check might be useful for other stage2
images as well but let's get started with this one.

Thanks Maxim Suhanov <suhanov/group-ib.ru> for both
http://www.forensicswiki.org/wiki/Forensic_Live_CD_issues
and propagator patches.

Thanks Maxim Suhanov (suhanov <AT> group-ib.ru,
http://www.forensicswiki.org/wiki/User:.FUF)
for taking the time to review regular-rescue image.

Note that there are more than just filesystems:
arrays, logical volumes and swaps aren't activated either;
startup-rescue >= 0.18 should make that clear enough.

syslinux shortcut handling is case-insensitive,
let's find yet another letter...

A variant of rescue that marks the need to be careful
towards block devices and filesystems thus reducing
the amount of auto-activation done by startup-rescue
(0.17 or newer).

Whoops, the very first build of a real distro with gfxboot
has shown that the label isn't picked up there... and things
are actually worse: iso.needscheck gfxboot test seems to look
up "check=1" in sectors where it might have been landing back
then but it's just not there by now; some kludgery is due in
branding-altlinux-sisyphus unfortunately.

Just a humble config snippet for another squashfs;
note that @bootargs@ aren't expected at all this time.

It's not exactly obvious how install2_size, live_size or rescue_size
get defined since the variable names themselves get constructed;
help git grep these down.

This change is done to reduce ambiguity in some cases;
the previous intention has been to ease navigation when
staying in a particular directory, now it's been changed
in favour of convenient toplevel `git grep' in fact.

Both variants have their pros and cons, I just find myself
leaning to this one by now hence the commit.  Feel free to
provide constructive criticism :)

Some path-related bitrot has also been fixed while at that.

Actually a copy of 10localboot.cfg with a different name
and sorting order so as to address #26608: there's no possibility
to make a LiveCD image that would boot itself by default if localboot
has been configured in.

It's only a partial solution as it doesn't override 10localboot
in case it's there already but a step in that direction...

The initial revision was brilliantly buggy: it is *so* apparent
that cdrom will never be actually used for rw slice that this
has evaded my attention rather completely.

"prompt" and subsequent first "label" were not separated
in any way while second "label" and forth were; let's make
the resulting isolinux.cfg a tiny bit more pretty.

alterator-netinst currently relies on "default"
being specified explicitly; it's wrong and it should
cope with the first "label" clause as well but we're
better off being strict to this script, not that one.

This commit should be no-op regarding syslinux itself.

There's a need for a separate boot target since
persistent storage is way slower than tmpfs indeed;
usbflash has a tendency for huge performance drops
given simultaneous writes in addition to reads which
are the bottleneck already.

make-initrd-propagator 0.18 introduced ext4 rw slice,
so the corresponding kernel module needs to be included
into stage1; see also #28289.

NB: not available on x86_64-efi (or hybrid GPT to be strict)
due to fragility of the hack being made: parted(8) panics
upon seeing that, and good ol' fdisk is unable to treat it.

NB: use/live/rw use/rescue/rx use/syslinux/ui/gfxboot
are unlikely to play very nice together due to the latter's
magic l10n: "session" label is taken by live_rw config snippet
and *is* translated in design-bootloader-source;
OTOH "rescue_session" is *not*.

The issue is that gfxboot's gettext support works on "label"
strings but doesn't work properly on "menu label" ones as of 4.04
(the "menu label" translations pop up in the "Loading ..." window
but menu items themselves are unaffected thus untranslated).

NB: debian wheezy's syslinux-4.05 package patchset contains
somewhat related 07-gfxboot-menu-label.patch; might be worth
attention given that debian folks participate in upstream.

The reason is that the most interesting live images by now are
installable ones, and while configurable boot order is not there yet
the "classic" livecd images will require manual choice to boot.

Thanks sem@ for reminding of that FR (which is still open).

Its immediate purpose was influencing the GRUB boot menu
*but* the implemented mechanism is actually a part of the
long planned text branding and might be further merged
into branding when hierarchical features finally chime in.

So let's get the naming straight before it breeds.

File contents should be correct.

That sub/stage2/install2 was somewhat clumsy actually as it looked
like a hierarchical thing while being a substitution thing:
generic stage2 would get put in place renamed as install2.

This could only get worse with hierarchical features which have
already been both requested and considered for quite a time,
and "stage2 at install2" reads much more naturally.

There's no (convenient) "eject" at times, so it's better to provide
extra ways of booting right away.

This trots along the TODO item on text branding
and hopefully helps Michael Radyuk (torabora)
with his feature request to tweak the installer's
"Install ALT Linux" label; as an example, Simply
will now offer to "Install Simply Linux".

This one was suggested by enp@ for industrial use where
some extra protection for the boot process might be quite
desirable.

If no syslinux ui was specified (the stock configuration paths
ensure there is one) or if it was set to "none" explicitly,
then there's no boot: prompt (let alone any menu).

If there's a need to ensure that the boot process is not
interruptable by Ctrl/Shift/Caps Lock/Scroll Lock.

The problem was spotted by Alexander Bandura:
bin/tar2vm wasn't present in the generated profile.

I considered extending features.in/Makefile to include
bin/ alongside lib/ but that would make the helper's location
unpredictable (unless BUILDDIR is specified explicitly) so
restricting sudoers would be harder; worse yet, the copied file
would come with write access for the user building an image.

The implications in restricted case are complex enough anyways
so the recommended implementation would only include a fixed
readonly location like /usr/share/mkimage-profiles/bin/tar2vm
as laid out in doc/vm.txt, and that means it's in the metaprofile
not a generated profile.

It's configured by plymouth feature when needed;
install2 bootargs support is generalized a bit
to become stage2 one as was intended anyways.

Keyboard accelerators rather make sense
with menu/vesamenu UI.

An initial draft of it was done half a year ago but several tricky
thingies had kept the code from showing up as it was rather brittle
and incomplete.

This implementation involves quite a few changes all over the place
but finally works good enough for live and installer images.

Please pay attention to the versions of these packages:
- installer-feature-setup-plymouth (0.3.2-alt1+)
- branding-altlinux-sisyphus (20110706-alt2+ if used)
- plymouth (0.8.3-alt20.git20110406+)

See also:
- http://www.altlinux.org/Branding
- http://www.altlinux.org/Plymouth

As duly noted by glebfm@, branding issues need more attention
by now since only stage1/install2 got some of it so far in this
regard.  Hence the dedicated feature comes to the rescue
(well no, it doesn't actually mess with rescue!).

- incompatible change (to fix the rather broken early style):
  use/syslinux/ui-% is now use/syslinux/ui/%;

- default timeout changed to 9 seconds (long enough and keeps
  the countdown in a single figure);

- added totaltimeout of 300 seconds;

- provided live kiosk images with almost-instant boot by default;

...and some other assorted tweaks here and there, sorry.

There's much reason for reuse instead of duplication
among the different stage2-based subprofiles.

In particular, the rather monolithic driver cleanup script
of the ancient is better done in several clear pieces with
the final depmod run.

Scripts dropping apt/rpm databases will dump pkglist first.

A script purging /boot/* will honour live-install if present.

Minor inno^Wfixups all over the map too.

As was noted by Alexey Shabalin in libosinfo context,
current ALT Linux images tend to lack ISO9660 metadata
-- which they did have back in the day of Master 2.4.

Please note that the data collection occurs this way
due to mkimage's config.mk resetting the values to be
empty; this was worked around by using another config
file, $(BUILDDIR)lib/iso.mk, and including it later
but that would require a separate target with per-target
CONFIG variable which isn't elegant at all given the need
to actually build up the metadata set.

So the variables were changed (to be more readable anyways)
and then proxied back to BOOT_*.  This might be cleaned up
some day after the inclusion order is tweaked or mkimage
defaults get set-if-unset-yet (?=).

Avoid extra files where a variable would suffice; and use
the more specific "syslinux.list" rather than a "files.list".

Fixed up the remnants of the early style mix
to correspond to the proposed doc/style.txt;
the rationale being that

	if [ ... ]; then
		...
		...
	fi

is the more readable construct among itself,

	if test ...; then
		...
		...
	fi

and

	[ ... ] && {
		...
		...
	}

due to the condition being more distinguishable
when bracketed and the body more apparent as the
one inside "if" and not any other block; the less
obvious difference is that the final construct of
the latter form is prone to the whole script exit
status being non-zero if the condition isn't met.

- parameter order fixed to "simple first, then those with args"
  and documented as the preferred one (might be debatable, okay)
- added "lowmem" to live so it avoids a ramdisk but works off media
  (it's a knob for propagator)
- added "fastboot" everywhere (but failsafe install) to make use
  of Linux 2.6.29+ async controller initialization
- every snippet got a trailing newline so that isolinux.cfg is readable

And a fancy makefile to check for shortcut dups!

As noted by imz@ in #26608, a LiveCD is the more preferred
boot target to a local drive usually (just as was discussed
and implemented for ALT Linux 4.0 IIRC).

It's now possible to:
- make distro/server-ovz.iso;
- make distro/server-ovz-netinst.iso;
- publish the former image's contents on ftp.linux.kiev.ua;
- boot the latter (~17M) image and enjoy the netinstall ;-)

The catch is that the stage2 (altinst file) location has to be
hardwired into syslinux config snippet for things to happen
automatically -- even if it can be specified manually in case
of failure.

The other catch is that currently a netinstall image is somewhat
tied to the particular image it installs since stage1 kernel and
stage2 modules must correspond strictly (the typical symptoms of
the glitch would be missing mouse driver and weird "permission
denied" errors during an attempt to partition the hard drives).

It might be desirable to provide multi-distro netinstall image...

The features might get copy-pasted (or even copied-and-pruned)
when initialized; there's an unneccessary duplication of the
function name in the line adding it to FEATURES list, thus
prone to being forgotten and causing some havoc later on.

It was wrong in the first place but tackling this with some
double-colon rules ran into terminality issues, and further
tortures were considered unneccessary.

The current solution isn't perfect (no completely transparent
function name registration upon corresponding target being called)
but at least it is an improvement...