Add IP[V6]_[RECV]ORIGDSTADDR for Linux and Android

[vi]

No description provided.

[rust-highfive]

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[asomers]

These constants are defined on FreeBSD 12, too. You should add them to all platforms that define them, not just Linux.

[vi]

Is only FreeBSD missing? How do I know exhaustive list of platforms I need to add? Is just googling sufficient or one supposed to actually run a fresh release in a VM and check if it's there or not?

[asomers]

You aren't expected to run your own VM for every single platform. That's CI's job. But figuring out which platforms support a certain symbol is something that you can do. The easiest way is to check online man pages. That works well when binding functions. For constants you may need to look at the sources. Here are some of the resources I use:
https://www.freebsd.org/cgi/man.cgi
https://svnweb.freebsd.org/base/head/
http://netbsd.gw.com/cgi-bin/man-cgi?++NetBSD-current
http://cvsweb.netbsd.org/bsdweb.cgi/src/?only_with_tag=MAIN
https://man.openbsd.org/
https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/
https://leaf.dragonflybsd.org/cgi/web-man
https://gitweb.dragonflybsd.org/?p=dragonfly.git;a=summary
https://github.com/illumos/illumos-gate

It's hard to find definitive answers for Linux because it's so fragmented. But a VM can give pretty good answers, even if they aren't perfect. The hardest platform to research is OSX. I pretty much use Google for OSX.

[gnzlbg]

The hardest platform to research is OSX. I pretty much use Google for OSX.

For MacOS X you can search for the MacOSXSDK headers, e.g., this repo contains most of them: https://github.com/phracker/MacOSX-SDKs The only thing to keep in mind is that for i686-apple-darwin macosx headers types sometimes use #pragma pack but that's hidden behind macros (CI will tell you about this though).

Maybe we should compile some of this information to the contribution docs.

[gnzlbg]

@bors: r+

[bors]

📌 Commit 4d0694c has been approved by gnzlbg

[bors]

⌛ Testing commit 4d0694c with merge a8a817a...

[bors]

☀️ Test successful - checks-cirrus, checks-travis, status-appveyor
Approved by: gnzlbg
Pushing a8a817a to master...

[asomers]

Why did you merge the PR even though it was incomplete, @gnzlbg ?

[gnzlbg]

I thought we could add the FreeBSD 12 constants in a subsequent PR (as in, no need to block this part from landing on that).

[vi]

I tried searching superficially for IP_ORIGDSTADDR using provided links and found nothing relevant for any of those apart from FreeBSD.

But looking at https://reviews.freebsd.org/D9235 and git grep-ping other constants in libc source code releals lack of not just ORIGDSTADDR-related things, but also previously numbered constants like IP_BINDMULTI, IP_RSS_LISTEN_BUCKET. Shall those be added along the way?

For IPV6_* it is even more pronounced: by selectively searching mentioned constnats I fail to find things higher than IPV6_V6ONLY (27). Shall all of them also be shoveled into src/unix/bsd/freebsdlike/freebsd/mod.rs? Or it needs more elaboration to distribute between unix/bsd/freebsdlike/freebsd, unix/bsd/freebsdlike, unix/bsd and unix?

---

Are those things supposed to be auto-generated from headers (or closely track platorm's respective header files) or each item should be judged on case-by-case basis?

[asomers]

Yeah, libc has plenty of missing definitions. You don't need to worry about fixing all of them, but it's good not to make things worse. You can CC me as a reviewer if you want.