gh-129719: Restore missing socket.CAN_RAW_ERR_FILTER on Linux

[jbogers]

Restore socket.CAN_RAW_ERR_FILTER on Linux by looking at the HAVE_LINUX_CAN_RAW_H flag, as the linux/can/raw.h file defines this value in an enum and not a normal define.

As linux/can/raw.h should always contain the value, I believe this change is safe to make.

• Issue: socket.CAN_RAW_ERR_FILTER is not defined in Python 3.11 and later #129719

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📚 Documentation preview 📚: https://cpython-previews--129721.org.readthedocs.build/

[ghost]

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[ZeroIntensity]

In the future, please don't force push; it just makes reviewing more difficult, and we squash merge at the end anyway.

Regarding the actual change: do we want to backport this? (Not to 3.11, but we could to 3.12+)

cc @erlend-aasland who added it originally, and @serhiy-storchaka who merged the offending PR (GH-30066).

[ZeroIntensity]

I think this is trivial enough that we don't need a test. LGTM.

[jbogers]

I think this is trivial enough that we don't need a test. LGTM.

There has been no activity on this PR for a while. Is there an action I (as PR creator) have to take to move this forward? Or do I just have to wait? Either is fine with me, but I'm unfamiliar with the process and I want to be sure I'm not the one holding this up now.

[sobolevn]

Thank you, indeed the check is about

if test "x$ac_cv_header_linux_can_raw_h" = xyes
then :
  printf "%s\n" "#define HAVE_LINUX_CAN_RAW_H 1" >>confdefs.h

fi

[miss-islington-app]

Thanks @jbogers for the PR, and @sobolevn for merging it 🌮🎉.. I'm working now to backport this PR to: 3.13.
🐍🍒⛏🤖

[bedevere-app]

GH-132702 is a backport of this pull request to the 3.13 branch.