zip64 compatibility problems

Martin Buchholz martinrb at
Tue Jan 15 21:46:49 UTC 2013

Hi zip64 team!

It's always a problem creating zip files using new zip spec features,
since older zip implementations will fail to read those files.

I see the jdk8 fix to allow the launcher to read zip64 files

changeset:   5812:f1838d040cc7
user:        ksrini
date:        2012-09-05 11:38 -0700
7194005: (launcher) needs to be enhanced for 64-bit jar file handling
Reviewed-by: darcy, sherman

but that has not been backported to jdk7, which seems like a serious
problem to me.

More generally, most zip implementations, including in the jdk, worked
just fine with >64k entries, since the entry count field was generally
just treated as a hint.  The change to use zip64 when there are >64k
entries makes zip files *less* portable in practice for the next few
years.  It would have been better to default to writing non-zip64 zip
files in such cases.

Note that zip 3.0 does write zip64 files for >64k entries, but also
provides a flag -fz- to change the default.

I'd like to see a backport of 7194005 and am also aware of some other
issues with our ugly friend parse_manifest.c.

You changed calls to open to do this:

    if ((fd = open(jarfile, O_RDONLY
        | O_LARGEFILE /* large file mode on solaris */
#ifdef O_BINARY
        | O_BINARY /* use binary mode on windows */
        )) == -1)

But this is not done consistently - there are 2 other calls to open in
the same file that didn't get the LARGEFILE treatment.  Why isn't
there a JLI_Open?


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