RFR: 8360025: (se) Convert kqueue Selector Implementation to use FFM APIs [v4]

[Alan Bateman]

On Wed, 3 Sep 2025 12:08:49 GMT, Darragh Clarke <dclarke at openjdk.org> wrote:

> So I double checked the changes made there and wrote this up, I can make it more precise or change wording if its going to be attached to a file. Package info currently contains the script used to generate the code
> 
> **Common changes:**
> 
> * utility methods and constant values got moved into FFMUtils, this is to cut down on duplicated code as more FFM code gets added
> * kqueue_h and kevent both get updated to reference FFMUtils
> * `@SuppressWarnings("restricted")` is added above the class declarations
> 
> **kqueue_h specific changes:**
> 
> * Errno handling had to be added, this involved adding the `ADAPTED` method handles as well as editing the `HANDLE` methodhandle to add `Linker.Option.captureCallState(ERRNO_NAME));`
> * Removing some unused generated objects such as `static final Arena LIBRARY_ARENA = Arena.ofAuto();`
> * added `private static final String ERRNO_NAME = "errno”;`

It might also help if the integration were split into two. A first commit with the jextract-generated files, then a second that has the changes. That would capture in the git log the changes that were made, and would also make things much easier to review too as it would be obvious what has been changed.

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PR Comment: https://git.openjdk.org/jdk/pull/25546#issuecomment-3264814812