Re: [Vala] Binding 7zip library ?

[raum no-log org]

I had a look to libarchive... It seems libarchive 3.0 could handle 7Zip
format (for reading) but unfortunately there is only a vapi file for
version 2...

I've read some pages about "how to generate vapi" but I didnt success...

Should I try to write by hand a vapi file ?

Thanks

> On Mon, 2013-08-26 at 11:27 +0200, raum no-log org wrote:
> > Hello,
> >
> > I've downloaded and build 7Zip library and I've these files compiled
> > (under Windows using MingW32, with prefix /opt) :
> >
> > /src/lib7zip-1.6.5/Lib7Zip/lib7zip.a
> > /src/lib7zip-1.6.5/Lib7Zip/lib7zip.dll
> > /src/lib7zip-1.6.5/Lib7Zip/lib7zip.h
> >
> > "make install" command didn't copy these files under /opt/bin,
> > /opt/include, /opt/library
>
> The 7zip SDK really designed to be embedded within your project, not
> used as a shared library.
>
> > I've copied manually in the correct directory but tests programs output
> > :
> > # test7zip.exe
> > initialize fail!
> >
> > So I think I've made a mistake somewhere... But how to test it with a
> > vala
> > test program ? I need to build a vapi file ? something like that ?
>
> Yes, you would need to create VAPI.  I looked at the 7zip SDK API quite
> recently and I don't think creating a VAPI would be an easy task.  The
> API is a bit of a mess.
>
> I'm not sure what your use case is.  If you need to read and write *.7z
> files you might want to look at libarchive?I'm not sure whether they
> support 7zip or not, but if they do then it would be a much easier way
> to go since it already has a VAPI.
>
> If you just want to compress stuff you might want to take a look at a
> project I've been working on called Squash [1], which does have Vala
> bindings.  It is an abstraction layer for compression libraries (not
> archivers?that's what libarchive is for), and it supports most of the
> algorithms 7zip uses.
>
> I do plan to write a Squash plugin for the 7zip SDK eventually [2], and
> if you really need PPMD, BCJ, or BCJ2 (Squash already supports LZMA,
> LZMA2, bzip2, and DEFLATE) I can take a look at that sooner rather than
> later, but keep in mind that it will not support *.7z archives.
>
> Also, if you're not tied to 7zip, you may want to look at FreeArc [3].
> I don't remember if they have an API you could use or not, but the PPM
> compression is better, and the other algorithms are great [4].  Or, if
> all you care about is compression ratio, ZPAQ [5] (for which there is a
> Squash plugin) is amazing.
>
>
> -Evan
>
> [1] http://quixdb.github.io/squash/
> [2] https://github.com/quixdb/squash/issues/31
> [3] http://freearc.org/
> [4] http://compressionratings.com/i_freearc.html
> [5] http://mattmahoney.net/dc/zpaq.html