8351458: (ch) Move preClose to UnixDispatcher

[shruacha1234]

OpenJDK PR: openjdk/jdk#23956
OpenJDK bug: https://bugs.openjdk.org/browse/JDK-8351458

The original patch didn’t apply cleanly to the JDK21u-dev branch due to a copyright header mismatch. However, the rest of the changes were ported without issues. Manually updated the copyright header to resolve the conflict.

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Progress

• JDK-8351458 needs maintainer approval
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8351458: (ch) Move preClose to UnixDispatcher (Enhancement - P4)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk21u-dev.git pull/2051/head:pull/2051
$ git checkout pull/2051

Update a local copy of the PR:
$ git checkout pull/2051
$ git pull https://git.openjdk.org/jdk21u-dev.git pull/2051/head

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Checkout this PR locally:
$ git pr checkout 2051

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Download this PR as a diff file:
https://git.openjdk.org/jdk21u-dev/pull/2051.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back sacharya! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

@shruacha1234 Please do not rebase or force-push to an active PR as it invalidates existing review comments. Note for future reference, the bots always squash all changes into a single commit automatically as part of the integration. See OpenJDK Developers’ Guide for more information.

[mlbridge]

Webrevs

• 01: Full - Incremental (57e506ff)
• 00: Full (d53a3cd5)

[shruacha1234]

/approval JDK-8351458 request Clean backport, Refactored to move "prepare for close" logic into UnixDispatcher to simplify code and handle blocked threads during socket close more effectively in 21u-dev.

[openjdk]

@shruacha1234
JDK-8351458: The approval request has been created successfully.

[openjdk]

⚠️ @shruacha1234 the commit cabd1fa3863b1fced596889fd15e197d2ee96b19 does not refer to an issue in project JDK.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[openjdk]

@shruacha1234 Please do not rebase or force-push to an active PR as it invalidates existing review comments. Note for future reference, the bots always squash all changes into a single commit automatically as part of the integration. See OpenJDK Developers’ Guide for more information.

[jerboaa]

@shruacha1234 Please read https://openjdk.org/projects/jdk-updates/approval.html

In particular in Rule 1 it says:

[...] In that comment the requester must describe why it's important
to fix this bug, explain the nature of the fix, estimate its risk and describe
its test coverage. [...]

Nothing like that is in the existing fix request comment.

[openjdk]

⚠️ @shruacha1234 This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.