RFR: 8343342: java/io/File/GetXSpace.java fails on Windows with CD-ROM drive [v8]

[Brian Burkhalter]

On Fri, 13 Dec 2024 10:10:16 GMT, Taizo Kurashige <duke at openjdk.org> wrote:

>> To resolve java/io/File/GetXSpace.java failure, I fix libGetXSpace.c to use  Cygwin’s `df` to get the size for comparison if the test target drive is a CD-ROM drive.
>> 
>> As described in JDK-8343342, GetDiskSpaceInformationW can't get information about the size of the CD-ROM drive. 
>> GetDiskFreeSpaceExW can also get information about the size of the CD-ROM drive. However, because GetDiskFreeSpaceExW is called by the File.get-X-Space methods, it seems more reasonable to compare the size got by other way than GetDiskFreeSpaceExW as a test. For this reason, I use Cygwin's `df`.
>> In JDK-8298619, GetDiskSpaceInformationW was adopted instead of `df` because the size got by File.get-X-Space methods may not match the size got by `df` when per-user quotas are used. I don't think this problem applies to CD-ROM  drive, so I think we can use Cygwin's `df` for CD-ROM drive.
>> 
>> After fix, I ran a test on Windows Server 2019 where drive C is a normal local disk, drive D is an unmounted iso CD-ROM  drive, and drive F is an iso mounted CD-ROM drive and confirmed that it passes.
>> 
>> I think this fix may also resolves the similar failure reported at https://github.com/openjdk/jdk/pull/12397#issuecomment-1705164515.
>> 
>> Thanks
>
> Taizo Kurashige has updated the pull request incrementally with two additional commits since the last revision:
> 
>  - Fix getCDDriveSpace()
>  - Fix macro for unix

It fails for me on a Windows 11 laptop with an external CD drive with a CD inserted. On Cygwin the `df` command gives:

$ df
Filesystem                    1K-blocks      Used Available Use% Mounted on
C:/Users/bpb/dev/tools/cygwin 496752636 166105620 252373420  40% /
D:                               493658    493658         0 100% /cygdrive/d

The test prints (omitting the `C:` drive):

D:\ (0):
  getCDDriveSpace total =            0 free =            0 usable =            0
  getXSpace total =    505505792 free =            0 usable =            0

and fails with:

FAILED: 'D:\ total space': 505505792 > 0
FAILED: 'D:\ size': 505505792 > 0
24 tests: 2 failure(s); first: java.lang.RuntimeException: 'D:\ total space': 505505792 > 0

Perhaps the output of `df` is not being parsed correctly?

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PR Comment: https://git.openjdk.org/jdk/pull/21799#issuecomment-2542388045