[crac] RFR: Improved open file descriptors tracking [v9]

[Radim Vansa]

On Mon, 24 Apr 2023 13:27:30 GMT, Radim Vansa <duke at openjdk.org> wrote:

>> Tracks `java.io.FileDescriptor` instances as CRaC resource; before checkpoint these are reported and if not allow-listed (e.g. as opened as standard descriptors) an exception is thrown. Further investigation can use system property `jdk.crac.collect-fd-stacktraces=true` to record origin of those file descriptors.
>> File descriptors claimed in Java code are passed to native; native code checks all open file descriptors and reports error if there's an unexpected FD that is not included in the list passed previously.
>
> Radim Vansa has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Provide more information for file descriptors

src/java.base/share/classes/jdk/internal/crac/JDKContext.java line 62:

> 60:         String classpath = System.getProperty("java.class.path");
> 61:         int index = 0;
> 62:         while (index >= 0) {

Bug: looks like the update of `index` was dropped somewhere, this loop may run infinitely...

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

PR Review Comment: https://git.openjdk.org/crac/pull/43#discussion_r1180410276