Re: Problems installing from Cygwinports

[Jon TURNEY <jon dot turney at dronecode dot org dot uk>]

On 31/03/2011 06:15, Yaakov (Cygwin/X) wrote:
> As a potential setup.exe bug, redirecting to cygwin-apps.
> 
> On Thu, 2011-03-31 at 00:54 +0200, Angelo Graziosi wrote:
>> It is sometime I have installed a few packages from Cygwinports 
>> (QT,GCC), but today upgrading (mainly *QT*-4.7.2-1 and *mesa*-7.10.1-2) 
>> 'setup.exe' seems to hang in extracting /usr/include/GL/glxext.h from 
>> libGL-devel-7.10.1-2.
> 
> Confirmed.
> 
> (The tarball in question is here:)
> ftp://ftp.cygwinports.org/pub/cygwinports/release-2/_DISTRO_/X.Org/mesa/libGL-devel/libGL-devel-7.10.1-2.tar.bz2
> 
>> Result: my hard drive (C:) is almost full, X does not start any more and 
>> I can use only Cygwin.bat and mintty. To be short, my Cygwin 
>> installation is broken :(
> 
> Start by deleting /usr/include/GL/glxext.h, that will free up your hard
> drive.  Then re-run setup, choosing to KEEP libGL-devel instead of
> upgrading.
> 
> Now, as for the cause, the only thing I can think of is that I just
> started using pbzip2 for compression in cygport[1].  The bz2's are
> supposed to be fully compatible, and neither Cygwin nor MinGW bzip2 have
> any problems with the tarball in question.
> 
> So my wild guess is that setup uses libbz2 in a way which is
> incompatible with pbzip2-compressed tarballs, as unlikely as it seems.  
> 
> Can any setup.exe authors shed any light on this?

I do actually want to install that package, so I took a brief look at this:

The first problem is that .bz2 file and the decompressor don't like each
other. The decompressor reports the stream has ended partway through
decompressing glxext.h.  It's very mysterious that it should fail but bunzip2
has no problems with the same file.

The second problem is a setup bug: If we get an unexpected short read from the
archive stream decompressor, we'll sit in an infinite loop writing garbage to
the output file 5 bytes at a time.  A patch is attached which fixes that, but
since these errors are  unreported (see comment in io_stream::copy), we just
stop expanding the archive, leaving an incomplete glxext.h

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