This was never implemented and it somewhat questionable. It might be
interesting in future to reintroduce it back and instead of having it as
a lua function to have it as shell script (run by something like
system()).

Why this is dropped is because it is questionable on how to implement
it. It requires to run function from script that is no longer available
potentially. It has to be run in transaction which has nothing to do
with original configuration scripts. This was just stupid design idea
and we should not implement it.

We do not download any package unless we know that they are going to be
installed with this commit. It is done by split of download to separate
function.

This replaces problematic data pass in Lua with files saved on disk.
Original problem is that Lua in some cases like closures duplicates
environment and that means also all data. If this happens few times
(from measurements it seems like two or three times in code segment we
are dropping in this) then we can have few times bigger memory
requirements.

This also temporally disables test test-sys-pkgupdate-plan-unapproved as
it does not expect additional files. This is going to be solved in
following commit.

This code was here because of package content option but this feature is
obsoleted and dropped so we can drop this code as well.

Previous commit fixed problem for existing localrepo.lua but introduced
an error for non-existing script.

OPKG implementation of upgrade is dangerous specially if applied to
system packages.

Output is already printed as part of subprocess function. Printing it
again is duplicative output.

This fixes some problems with boolean values in uci configs.

There is no reason why plan could not be denied after it was approved or
approved after deny.

This command was never implemented and it makes little to no sense to do
so because the same thing can be archived with os.execute that is core
part of Lua.

This was originaly introduced to allow local packages to be installed.
It was later replaced with localrepo and was marked as obsoleted for
long time.

Morpher is obsoleted for more than year and should not be used any more.
We are doing now huge changes with approaching Turris OS 4.0 and that is
best time to drop this.

This adds possibility to completely configure updater (autorun) trough
supervisor. Advantage of this is that supervisor is the only place that
defines uci configuration for updater (at least if we are talking about
autorun) and because of that same API can be used on top of generally
different configuration. This is handy because of back compatibility
with Turris OS 3.x and introduced cleanup in Turris OS 4.x.

This is much more appropriate name and this way we are able to integrate
all Turris specific configuration to same section called turris.

This is huge change but it makes sense. Original name is now pretty
confusing and it should be clear that this tool is part of updater-ng.
This new name should signal that.
This new name also contains whole word "transaction" so it should
possibly be more clearer what it really does. This also adds comment
that this tool is dangerous to play with.

This file was here for backward compatibility. It is long enough that
anyone should have already migrated away from it.

It makes much more sense to have it part of supervisor as a software
that handles automatic updater execution.

This script was required for migration between old versions of Turris OS
3.x. This is no longer required on Turris OS 4.x.

All warning in events are just suppressed because we are planning on
dropping events.c anyway.

I originally was thinking that Lua is doing something nasty like
duplicating original file descriptor for stdout but it turns out that
exec was a culprit. For some reason a call to exec truncates (or at
least removes unfinished line) from stdout. I have no idea why it
behaves that way but adding flush just after callback (before exec)
solves that problem and allows us to correctly use print in callback.
The weird part is that the same thing does not happen with stderr but
non the less I also added flush for it.

This also removes possibly hack to run C/Lua code in subprocess without
providing command. It is overhead but it is more systematic to use
'true' as a command instead of possibly in code unexpected value NULL.

Instead of pretty small constant lets use system level compilation
constant BUFSIZ. Thanks to that we should have buffer exactly matched to
stdio buffer which should somewhat ensure better performance. It is
minor thing but it is better to do it non the less.

This also adds message about termination of subprocess.

I probably had some plan with it but I no longer remember what it was
suppose to been. Instead I just drop it here. It can be reverted later
if needed.

This also correctly sets read field for cookie structure. This has no
effect because we are not reading from it but just to be precise with
our code we set it to know value NULL which means that read is not
available.

This changes timeout from seconds to milliseconds. This is consistent
with previous events design.
Previously used seconds had to be multiplied and milliseconds divided
respectively to hook to current code. This just makes more sense.