linux: add a few kTLS defintions

[gennyble]

related: nix-rust/nix#2065

i think android has support, too, but if I put it in linux-like does that imply emscripten support?

[rustbot]

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[fasterthanlime]

Thanks @gennyble for opening this!

I need this PR + a point release to (ultimately) land nix-rust/nix#2065 which in turn unblocks doing in-kernel TLS properly from rust with tokio, cf. bearcove/ktls#26

(I know, exciting!)

[gennyble]

TLS_GET_RECORD_TYPE is from a kernel header which might not be available where libc is built. What would you like me to do here?

I see a skip might be an option?

[fasterthanlime]

@JohnTitor would it be possible to get a look at this? Maybe from another maintainer, if you're not able to?

[JohnTitor]

TLS_GET_RECORD_TYPE is from a kernel header which might not be available where libc is built. What would you like me to do here?

I see a skip might be an option?

Correct.

[gennyble]

Instead of skipping I added the header to the linux kernel headers for libc-test.

@rustbot review

[JohnTitor]

Cool, thanks! @bors r+

[bors]

📌 Commit 94cfcd2 has been approved by JohnTitor

It is now in the queue for this repository.

[bors]

⌛ Testing commit 94cfcd2 with merge af676d1...

[bors]

☀️ Test successful - checks-actions, checks-cirrus-freebsd-12, checks-cirrus-freebsd-13, checks-cirrus-freebsd-14
Approved by: JohnTitor
Pushing af676d1 to main...

[fasterthanlime]

Thanks for getting this merged! When can we expect this to be included in a crates.io release of libc ? (So we can bump the version nix relies on)

[fasterthanlime]

@JohnTitor the latest libc release was cut on June 25, 2023 - I think this means this PR still isn't on crates.io? The problem is we're trying to use those new additions from https://lib.rs/crates/nix, so a git dependency isn't really an option here.

Edit: opened #3350 to track this

Edit 2: @joshtriplett released 0.2.148 just now.