Re: [PATCH 0/2][RFC] Add SWIG Bindings to libcpupower

[Shuah Khan]

Hi,

On 7/24/24 16:11, John B. Wyatt IV wrote:
> SWIG is a tool packaged in Fedora and other distros that can generate
> bindings from C and C++ code for several languages including Python,
> Perl, and Go. We at Red Hat are interested in adding binding support to
> libcpupower so Python tools like rteval or tuned can make easy use of it.

Can you elaborate on the use-case and what rteval currently does and
how it could benefit from using libcpupower with the bindings?

> This RFC provides a limited subset of bindings as a demonstration. The second
> commit provides a Python test script to verify the bindings. I wanted to get
> feedback on this before implementing (and possibly testing) the entire library.
>
> The name raw_pylibcpupower is used because this is a demonstration example that
> only provides direct bindings for a few functions. A wrapper `pylibcpupower`
> may be needed to make the bindings more 'pythonic'. The bindings folder is used
> because Go bindings may be useful for Kubernetes or OpenShift in the future.
>
> How should the bindings be built? The current example requires the makefile
> in cpupower directory be run first to generate the .o files needed before
> running the makefile in the python directory in a seperate step. Would the
> maintainers prefer the two makefiles integrated?

I can't answer this question until I understand the licensing.
However, I would lean towards keeping them separate.

> Another question is do you want more test files like the .py example? Would
> this be used as part of a greater test suite?

I would like to see document outlining the dependencies and examples of how
this would be used. I see the README which says that

"Next you will need to install SWIG. Using Fedora:"

The document will have to include more than Fedora instructions. Instead
of a README I would like to see a document.

Before we go any further - we have the licensing implications to figure out.

> Note that while SWIG itself is GPL v3+ licensed; the resulting output, the
> bindings code, is permissively licensed. Please see
> https://swig.org/legal.html for more details.

Adding Linus and Greg for their feedback and input on this proposal.

What does it mean by "the resulting output, the bindings code is
permissively licensed."

I would like to get a better understanding of the licensing angle
since this code adds dependency on SWIG which is GPL v3+ to build
the proposed python bindings.

thanks,
-- Shuah