libgsf and zip compression level

[Allin Cottrell <cottrell wfu edu>]

I wonder if I can drum up any interest in this bug:
https://bugzilla.gnome.org/show_bug.cgi?id=722470

Not sure how many third parties are using libgsf, but I'm one such 
and I find the library very useful -- so thanks!

However, it would be even more useful if the "compression-level" 
property of GsfOutfileZip actually worked as advertised, to govern 
the compression level on zipfile output. Right now it just acts as a 
binary switch: no compression, or zlib's Deflate compression at its 
default level (namely level 6). There's further explanation in 
bugzilla, plus a patch which I believe would cost nothing to apply.

My main reason for pushing this is that with big data the 
compression level can make quite a difference to the time taken in 
saving a zip file. There are diminishing returns: compression at the 
default level of 6 takes a lot longer than at (say) level 1, but 
does not produce a much smaller file. So there's a real use case for 
a gsf-using application to choose a level > 0 but less than the zlib 
default. Right now you can't do that but with my patch you can.

--
Allin Cottrell
Department of Economics
Wake Forest University