Declare setdomainname and getdomainname on Android.

[sunfishcode]

Description

Declare setdomainname and getdomainname on Android.

Sources

Android [supports] setdomainname and getdomainname in API level 26.

[supports] https://github.com/aosp-google/bionic/blob/28f9101d76b709febe25977f98530d77580387d1/libc/include/unistd.h#L236

Checklist

• Relevant tests in libc-test/semver have been updated
• No placeholder or unstable values like *LAST or *MAX are
  included (see #3131)
• Tested locally (cd libc-test && cargo test --target mytarget);
  especially relevant for platforms that may not be checked in CI

[rustbot]

r? @tgross35

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[tgross35]

Changes lgtm, but could you instead add this to src/unix/linux_like/mod.rs and remove them from linux and emscripten?

@maurer could you double check this?

[maurer]

LGTM, these two functions are in fact available since API level 26. Not aware of any special caveats for Android here other than that apps don't have CAP_SYS_ADMIN, so only platform code would be able to actually call the set side of this.

[tgross35]

Actually sorry, one request - since all linux_like OSs have this now, could you instead add the functions linux_like/mod.rs and remove from linux_like/linux/mod.rs and linux_like/emscripten/mod.rs? Same changes for the semver files.

[sunfishcode]

Which semver file corresponds to "linux_like"? Is it linux.txt? I can't tell whether that's used for Android or not.

[tgross35]

Ah you're right, we don't have one for linux_like. Leaving the existing .txt files unchanged and adding to android.txt, like you currently have, is probably the correct thing to do for the semver tests.

(this test setup needs improvement at some point...)

[tgross35]

Thanks!

[sunfishcode]

This failed on the arch64-linux-android build, and it's not clear what's wrong.

[tgross35]

I wish GH would send a notification for failed CI after merge. It was probably our spurious android failure, I'm not sure why it happens.