GEOM_ULZMA

[b. f.]

>> The code organization depends on what you want to do with it and how you
>> want to update the code in the future, if your lzma library is third party.
>
>LZMA made by Igor Pavlov, and since 4.62 it licensed under Public Domain.
>So we can use it, if we need.
>
>>
>> If you never intend to update the lzma code then I guess it's fine to
>> embed it in a big .c file. For a port, it doesn't matter much since it
>> is your own thing. There are stricter rules on maintainability and style
>> if you want it in the base system.
>
>So, I think right place for lzma library under sys/contrib directory, if I "promise" >maintain it?

There are already long-standing plans to import lzma compression
libraries into the base system, by the libarchive maintainers.  So you
will probably have to coordinate with them.  They have hooks in the
current libarchive sources for native lzma compression, but they
reportedly have been waiting for related file formats and compression
methods to stabilize before enabling them by default.  Pavlov has been
making significant changes from release to release, so this may not be
the easiest code to maintain.