Use libbpf-sys

[kriomant]

No description provided.

[rsdy]

Thanks so much for this, it looks great.

Apart from the non-trivial change of changing parsing code to unsafe, my only other ask is to re-push the contents of the patchset to please the DCO bot.

You can see more info about that process here

[rsdy]

Looking at the CI, we'll need to bump the build images to include pkg-config to successfully build this this branch.

[rsdy]

I am very confused why the CI doesn't pass on this with the exception of 20.04. Will need to fire up a bunch of Dockers to dig deeper.

[rsdy]

@rhdxmr CI seems to fail with an error saying Feb 13 13:44:42.856 DEBUG build_script_build: Generating bindings with BTF of vmlinux. Do you think you could look into this?

On aarch64 the error seems to be a bit more straightforward

 error[E0412]: cannot find type `__gnuc_va_list` in module `super`
   --> bpf-sys/src/type_gen.rs:273:54
    |
273 |     #[cfg(not(target_env = "musl"))] va_list: super::__gnuc_va_list,
    |                                                      ^^^^^^^^^^^^^^ not found in `super`

[rhdxmr]

@rsdy Okay I'll look into this problem and fix the issue.
It seems that there are two problems..

1. Failed to generate rust bindings for the Linux kernel structures from vmlinux BTF
2. Failed to compile in aarch64

I'll update this PR if I encounter another problem or find solutions.

[rhdxmr]

@rsdy
All problems are solved. I think it is okay now.
I double checked all modifications but it would be better if you check for the last time.

[rsdy]

Sorry for sitting on this review for so long. I wasn't super happy with the end implementation here, but after looking through libbpf-sys and weighing our options, it's not clear if this is a bug or known limitation on their end.

I raised an issue there so we can hopefully migrate completely off of bpf-sys once we clear this up. Thanks both!