The Wrapper Project

[Andreas Schneider]

On Wednesday, July 10, 2013 14:05:02 Jelmer Vernooij wrote:
> Hi Andreas,

Hi Jelmer,

> Great, thanks very much for working on that! It'd be great to have
> these available elsewhere.

thanks. 
 
> > On the way to get 'make test' in Samba working I found serveral bugs
> > which I already sent patches for. The remaining patches are my git
> > repository [4].  I've changed selftest to write a hosts file for
> > name resolution and changed waf to look for the preloadable system
> > version of the wrappers.  I have removed nss_wrapper, socket_wrapper
> > and uid_wrapper from the Samba source code for now. I want to
> > maintain and improve them outside of the Samba tree.
> > 
> > Currently the git trees live on my own infrastructure but I'm also
> > happy to create git repos on git.samba.org if you prefer that.
> 
> What committers/commit policy would you suggest for these?

The same as Samba once they are in a state I would consider them useable. 
Currently I need to be able to do changes very quickly. I try to write unit 
tests for all the changes. All the new hosts code in nss_wrapper has unit 
tests and I also wrote a testsuite for uid_wrapper.

> 
> > Yes, you have to install them first into the system before running
> > them. If you can't do that you can still set the LD_LIBRARY_PATH to
> > point to a directory where you have installed them. If you vote
> > against the removal of them from the Samba tree, then we could just
> > pull the code from time to time from the other repsositories like we
> > do it with heimdal or subunit.  I'm against this but we have
> > developers which would like to have everthing in the source tree.
> > Alternatively, we could use git submodules for that.
> > 
> > My work on the wrappers is not finished yet. They still need to be
> > checked on different platforms and we need more tests to easier
> > verify that they are working correctly. socket_wrapper is already
> > tested on several platforms [5] and works on MacOSX too.
> 
> The argument for keeping copies of the other software in-tree has
> always been that it should be possible to hack on samba without having
> to install a bunch of dependencies, as that may not be easy on all
> platforms. I guess you can still build Samba without the wrappers and that
> is probably sufficient - you only need to install these if you want to run
> the testsuite.

Well and if you run the testsuite it is normally efficient to install them 
once. The libc code doesn't change very often and I don't expect a lot of 
changes to happen. Maybe that someone adds new wrappers for functions but it 
is working very well on Linux right now.

> We need a strategy for the build farm hosts. It is annoying to
> install something as root on all build farm hosts - and to install
> newer versions when we come across regressions.

You don't have to install them into the system. You either set LD_LIBRARY_PATH 
or set LD_PRELOAD to point to them directly like

LD_PRELOAD=/path/to/libsocket_wrapper.so:/path/to/libnss_wrapper.so

> We should probably do the same (bundle, submodule, require
> installation) for testtools/subunit as we do for the
> wrappers.

Yes, this sounds reasonable!
 
> Personally, I would prefer using submodules and just having "make
> dist" include copies of the wrappers and testtools/subunit in the
> tarball and the tree that is used by the buildfarm hosts.

I don't expect that they need to be updated very often once they are in a 
working state. So they need only be updated when we add new features we will 
use in Samba.


	-- andreas