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.Dd April 30, 2020
.Dt CONFIG.LUA 8
.Os
.Sh NAME
.Nm config.lua
.Nd FreeBSD config module
.Sh DESCRIPTION
.Nm
contains configuration and module loading functionality.
.Pp
Before hooking into or using the functionality provided by
.Nm ,
it must be included with a statement such as the following:
.Pp
.Dl local config = require("config")
.Ss Exported functions
The following functions are exported from
.Nm :
.Bl -tag -width "config.setCarouselIndex(id, idx)" -offset indent
.It Fn config.getCarouselIndex id
Returns the currently chosen index in the carousel menu entry described by
.Ev id .
See the definition of
.Xr menu.lua 8
for a more in-depth explanation of carousels.
.It Fn config.setCarouselIndex id idx
Set the chosen index for the carousel menu entry described by
.Ev id
to
.Ev idx .
A lookup will be done as needed to determine what value
.Ev idx
actually corresponds to.
.It Fn config.readConf file loaded_files
Process
.Pa file
as a configuration file
.Po e.g., as
.Pa loader.conf
.Pc
and then processing files listed in
.Ev loader_conf_files
variable
.Po see
.Xr loader.conf 5
.Pc .
The caller may optionally pass in a table as the
.Ev loaded_files
argument, which uses filenames as keys and any non-nil value to
indicate that the file named by the key has already been loaded and
should not be loaded again.
.It Fn config.processFile name silent
Process and parse
.Ev name
as a configuration file.
Returns true if
.Ev name
exists and parses without error, false otherwise.
If
.Ev silent
is true,
.Fn config.processFile
will not consider a failure to read the file as a failure.
.It Fn config.parse text
Parse
.Ev text
as a configuration file.
This is used internally by
.Fn config.processFile
to parse the contents of a configuration file.
Returns true if parsing succeeds without error, false if an error occurred.
A message is also printed to the console if an error is encountered.
.It Fn config.loadKernel other_kernel
Attempts to load
.Ev other_kernel
as a kernel.
If
.Ev other_kernel
is unset
.Fn config.loadKernel
will attempt to load
.Dq kernel .
Otherwise, it will try to load
.Dq kernel
first from
.Pa /boot/{other_kernel} ,
then from
.Pa {other_kernel} .
.Pp
The latter is tried in case an absolute path has been specified to the kernel
to use.
.Ev module_path
is amended to include the directory the kernel was found in if either of these
paths result in a loaded kernel.
.Pp
If no kernel was loaded from either of these paths,
.Fn config.loadKernel
will attempt to load a kernel named
.Dq {other_kernel}
from
.Ev module_path
instead of attempting to load a kernel named
.Dq kernel .
.Pp
Returns true if a kernel was loaded, false if no kernel was loaded.
.It Fn config.selectKernel kernel
Set
.Ev kernel
to the kernel that will be loaded when either
.Ic autoboot
or
.Ic boot
are invoked.
This is usually called by the menu system as the kernel selector carousel is
toggled through.
.It Fn config.load file reload
Loads
.Ev file
as a configuration file.
If
.Ev file
is not specified,
.Pa /boot/defaults/loader.conf
is used.
.Fn config.load
will then silently attempt to process any files specified in
.Ev loader_conf_files
after
.Ev file
has been processed.
.Xr nextboot 8
configuration will also be checked as part of
.Fn config.load .
Before returning, all
.Dq config.loaded
hooks will be run if
.Ev reload
is not set to true.
.It Fn config.reload file
Reloads
.Ev file
as a configuration file.
.Fn config.reload
will restore the environment to how it existed before the last config was
loaded, then it will invoke
.Fn config.load file .
Before returning, all
.Dq config.reloaded
hooks will be run.
.It Fn config.loadelf
Loads all ELF objects, the selected kernel as well as any modules configured to
be preloaded in
.Xr loader.conf 5 .
This will be called by the Lua intercepted
.Ic autoboot
and
.Ic boot
commands.
.El
.Ss Defined Hooks
The following hooks are defined in
.Nm :
.Bl -tag -width "config.reloaded" -offset indent
.It Fn config.loaded
.It Fn config.reloaded
.It Fn kernel.loaded
.It Fn modules.loaded
.El
.Sh SEE ALSO
.Xr loader.conf 5 ,
.Xr loader 8 ,
.Xr menu.lua 8 ,
.Xr nextboot 8
.Sh AUTHORS
The
.Nm
file was originally written by
.An Pedro Souza Aq Mt pedrosouza@FreeBSD.org .
Later work and this manual page was done by
.An Kyle Evans Aq Mt kevans@FreeBSD.org .