Codereview request for 7130915: File.equals does not give expected results when path contains Non-English characters on Mac OS X

[David Kocher]

Will this address issue MACOSX_PORT-165 [1]? 

[1] http://java.net/jira/browse/MACOSX_PORT-165

-- David

On 22.06.2012, at 19:01, Xueming Shen wrote:

> Hi
> 
> Here is the proposed change to support Unicode nfd/nfc and case insensitive
> file path on MacOSX file system.
> 
> 7130915: File.equals does not give expected results when path contains Non-English characters on Mac OS X
> 7168427: FileInputStream cannot open file where the file path contains asian characters [macosx]
> 
> While these two bug reports are only against java.io, we have the same issue in javax.nio.file.
> Here is the webrev
> 
> http://cr.openjdk.java.net/~sherman/7130915_7168427/webrev/
> 
> Here is the brief summary of the changes
> 
> java.io.File:
> (1) removed nfc->nfd conversion in io_util.h/WITH_PLATFORM_STRING, which means
>     we are now passing nfc/composite characters directly into macosx file system APIs
>     without  normalize them to nfd. It appears macosx fs APIs do take nfc, though it uses
>     nfd.
> 
> (2) normalize the resulting file name from macosx fs APIs from nfd->nfd before passing
>     back to java.io.File (File.list() and canonicalize()), so we deal with nfdc file name
>     (as "usual")  for java.io classes/APIs.
> 
> (3) fs.compare()/hashCode() was updated to be case insensitive
> 
> (4) hasCode() was updated to use the new String.hash32().
> 
> java.nio.file:
> 
> (5) added a setof MacOSXFile... on top of existing BsdFile... classes. An alternative is to
> update those BsdFile... classes directly to address the macosx specific issues. But given
> there might be developers over there might work on open jdk BSD port and have dependency
> on these classes, it might be desirable to have another separate layer of MacOSXFile...
> classes. So now the default FileSystem/Provider is MacOSXFileSystemProvider and
> MacOSXFileSystem.
> 
> (6)  the "main" changes are in MacOSXFileSystem, in which the corresponding methods
> were added to handle, case insensitive and nfd<=>nfc normalization, including the
> pathmatcher.
> 
> (7) compare is now are case-insensitive
> 
> (8) hashCode is now murmur3_32(), this is true for all Solaris/Unix/Linux and maxosx.
> 
> 
> Though lots of files have been touched, but the line of changes are actually relatively
> small.
> 
> The proposed change only deals with the default case-sensitiveness seting, which is
> case insensitive. On MaxOSX, you actually can configure the HFS+ file system or the
> mounted vol to be case-sensitive. A possible approach is to have some extra FileStore
> attributes, such as a isCaseSensitive and to use case sensitive compare/equal on
> such fs, but this can be dealt with separately later.
> 
> Thanks,
> -Sherman
>