We support both of the following cases of substitution:
bar="y"
foo="${bar}"
foo="$bar"
The latter substitution syntax is, of course, not recommended- all
punctuation must be considered potential variable names, and we do not go
through the effort of searching the different combinations of, for instance,
"$x.y.z" to determine if the variable is $x, $x.y, or $x.y.z.
This is not officially documented as supported, but it has worked in
forthloader for what is most likely a long time as `evaluate` is used to
process the right hand side of the assignment.
loader.conf(5) documents loader_conf_files to mean "additional configuration
files to be processed right after the present file." However, lualoader
ignored loader_conf_files after processing /boot/defaults/loader.conf.
Rewrite these bits to process loader_conf_files after each loaded file.
This will not be executed on reload, though later work could allow for that.
It's intended/expected that later work won't generally need to happen on
every config load, just once (for, e.g., menu initialization) or just when
config is reloaded but not upon the initial load.
- No need for a 'goto' when our entire loop body is then wrapped in a
conditional.
- No need to leave commented out prints laying around
- If an expression is clearly going to be either nil or an expression that
isn't likely to be a boolean, we might as well use `or` to specify a
default value for the expression. e.g. `loader.getenv(...) or "no"`
The previous iteration of this assumed that {module}_load was set. In the
old world order of default loader.conf(5), this was probably a safe
assumption given that we had almost every module explicitly not-loaded in
it.
In the new world order, this is no longer the case, so one could delete a
_load line inadvertently while leaving a _name, _type, _flags, _before,
_after, or _error. This would have caused a confusing Lua error and borked
module loading.
This pertains exclusively to the set/restore functionality that we offer,
where any changes made by loader.conf previously will be effectively removed
upon reload of the configuration. We don't currently have a need to export
these, so don't bother.
See: comments in the hook module about intended usage, as well as the
introduced use for config.reloaded.
Use the newly introduced hook module to define a "config.reloaded" hook.
This is currently used to register core's clearKernelCache as a reload hook
to avoid a circular dependency and fix this functionality- it didn't
actually work out, and it isn't immediately obvious how it slipped into src.
Other hook types will be introduced into the core lualoader as useful hook
points are identified.
With autodetection turned on, hitting the filesystem everytime we need to
calculate choices for the kernel carousel is kind of slow. Cache once on the
first listing and reload it anytime the config is reloaded in case any of
the loader.conf(5) changes that affect this (kernel, kernels,
kernels_autodetect) have changed. This also picks up the case where we've
changed currdev and the autodetected kernels could change.
This applies to:
- exec
- [module]_before
- [module]_error
- [module]_after
Before this commit, these used loader.perform to execute them as a pure,
unsalted loader command. This means that they were not able to take
advantage of any Lua-salted loader commands, like boot and autoboot, or pure
Lua loader commands (functions attached to the 'cli' module).
They now have access to the full arsenal, just shy of being able to execute
arbitrary Lua.
Rather than hardcoding these things. This could lead to some form of loader
localization later, but the main goal at the moment is to get a clear view
of the strings we're outputting and strive to use more string.format() and
less wild concatenation all over the place.
Our module bits ended up more stable than I anticipated, so this turns out
to be no longer useful.
If things like this need to come back, we should do it in a separate 'debug'
module to serve as a collection of debugging aides. As a rule, this 'debug'
module would *not* be allowed as a requirement of any other modules in-tree.
These indices were assigned the same values as they would've been implicitly
assigned anyways.
While here, throw terminating commas after the last value of tables.
It should use the common parser, but it should not be processed like a
standard file. Rewite check_nextboot to read the file in, check whether it
should continue, then parse as needed.
This allows us to throw the recently introduced check_and_halt callback
swiftly out the window.
config.parse is now purely a parser, rather than a whole proccessor. The
standard process for loading a config file has been split out into
config.processFile.
This clears the way for having nextboot read its own config file and decide
there whether it should parse the rest of the file.
This is step 1 towards revoking config.parse of it I/O privileges. Ideally,
all reading would be done before config.parse and config.parse would just
take text and parse it rather than being charged with the entire process.
Functionally, the latter error wouldn't necessarily hurt anything. io.write
will just error out as it's not passed a valid file handle. Still, we can do
better than that.
The functionality was correct, but our style guidelines tend to request that
we shy away from using boolean operations in place of explicit comparisons
to nil.
config.parse now takes an extra callback that is invoked on the full text of
the config file. This callback dictates where we should actually try to
parse this file or not.
For nextboot, we use this to halt parsing if we see 'nextboot_enable="NO"'.
If we don't, parse it and write 'nextboot_enable="NO" ' to it. The same
caveat as with forth still applies- writing is only supported by UFS.
The latter is good, but the former is more elegant and clear about what 'x'
is. Adopt it, preferably only using the latter kind of notation where needed
as values for tables.
Graphics have a tendency to cause 80-col issues, so make an exception to our
standard indentation guidelines for these graphics. This does not hamper
readability too badly.
Two 40-column strings of spaces is trivially replaced with
string.rep(" ", 80)
luacheck pointed out an assortment of issues, ranging from non-standard
globals being created as well as unused parameters, variables, and redundant
assignments.
Using '_' as a placeholder for values unused (whether it be parameters
unused or return values unused, assuming multiple return values) feels clean
and gets the point across, so I've adopted it. It also helps flag candidates
for cleanup later in some of the lambdas I've created, giving me an easy way
to re-evaluate later if we're still not using some of these features.
I can't find any good reason these aren't enabled, so enable them.
The silent runs will only return false on actual parse errors, so it's ok to
be loud about those failures.
This was also a convenience convention (for me) that is not very lua-tic.
Drop it.
I've maintained some parentheses where I'd prefer them, for example,
'if x or y or (z and w) then', but these situations are far and few between.
This was previously chosen out of convenience, as we had a mixed style and
needed to be consistent. I started learning Lua on Friday, so I switched
everything over. It is not a very lua-nic convention, though, so drop it.
Excessive parenthesizing around conditionals is next on the chopping block.
Track the latest value we've set an environment variable to, and only
restore those that are unchanged from that.
This gives us some leeway to make sure we're not clobbering variables
overwritten by menu changes.
If the user's selected a kernel, we really should be trying to load that one
instead of falling back to some default kernel.
This should generally be a no-op and most desirable, unless you really
enjoyed surprises.
Carousel storage doesn't need to happen in the menu module, and indeed
storing it there introduces a circular reference between drawer and menu
that only works because of global pollution in loader.lua.
Carousel choices generally map to config entries anyways, making it as good
of place as any to store these. Move {get,set}CarouselIndex functionality
out into config so that drawer and menu may both use it. If we had more
carousel functionality, it might make sense to create a carousel module, but
this is not the case.
We follow pretty closely the following structure of a module:
1. Copyright notice
2. Module requires
3. Module local declarations
4. Module local definitions
5. Module exports
6. return
Re-organize the one-offs (config/drawer) and denote the start of module
exports with a comment.
lualoader does a pretty good job of reverting any environment changes now.
It will even wipe out boot_verbose if it's set explicitly in loader.conf(5)
and overwritten in the boot options menu.
Future work will likely change this, as explicit choices made in the menu
should probably override the new loader.conf(5). I don't suspect this will
cause much grief, though, so it is not a high priority until boot
environment support actually lands.