RFR: 8343020: SecureDirectoryStream not supported on MacOS [v2]

[Brian Burkhalter]

On Fri, 25 Oct 2024 16:10:20 GMT, David M. Lloyd <duke at openjdk.org> wrote:

>> OpenJDK will not produce SecureDirectoryStreams on MacOS. Support for SecureDirectoryStream on UNIX-like OSes is predicated on the `SUPPORTS_OPENAT` flag in UnixNativeDispatcher. That flag in turn is set when the runtime environment supports `openat`, `fstatat`, `unlinkat`, `renameat`, `futimesat`, and `fdopendir`.
>> 
>> This fails on MacOS because `futimesat` does not exist on that platform, apparently having been a proposed-but-not-accepted part of POSIX some time ago. While there is an indirect replacement that is supported on MacOS - `utimensat` - this is not actually needed, because the unique functionality provided by `futimesat` (that is, performing the action of `futimes` relative to an open directory file descriptor) is not utilized, since the only place this function is used passes `NULL` as the relative filename argument.
>> 
>> Replacing this with simply calling `futimes` instead allows `SecureDirectoryStream` to function on MacOS.
>
> David M. Lloyd has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Use 64-bit variation when 64-bit inodes are detected on macos x86

I think you will need to add the issue ID to the `@bug` tag of the test.

-------------

PR Comment: https://git.openjdk.org/jdk/pull/21696#issuecomment-2438323175