Re: [lwip-members] Shared library

[Adam Dunkels]

Hi!

On Thu, 2002-10-24 at 16:52, Kieran Mansley wrote:
> The problem someone brought up on the mailing list today (having to add
> <blah>_init() calls to the application) is one that has been bugging me
> for a while and I've been meaning to get round to fixing.  The solution
> (for unix systems) is fairly straightforward, and simply involves making
> it a shared library that can initialise itself.  I've already done most of
> this for my own setup, but I don't want to make changes to the CVS
> repository if there are issues that might affect other people.
>
> My concerns are:
> 
> 1) I could quite easily make the changes to unixsim and minimal projects,
> but would the lack of initialization code confuse people who are making
> their own projects and aren't used to shared libraries?  The existing
> method would still work as before so hopefully this shouldn't be too bad.

I think a better way would be to add a new directory under /proj, say,
/proj/unixlib, and leave unixsim and minimal as they are. I'm not sure
how many who would use lwIP as a shared library, compared to using it as
a "static library", i.e., just integrate it with their current project.
So leaving those two examples intact probably is a good idea.

Also, I have been using the unixsim and minimal projects to test both
compilation and functionality, and would like to keep them as they are
today without any special stuff like shared libraries.

Or maybe we should make a radical change and move the /proj hierarchy
out from the main lwIP code and into a module of its own? 

> 2) What platforms do we currently expect unixsim and minimal to work on?
> Do these all support shared libraries in the way unix does?  Writing
> architecture specific makefiles probably isn't worth it for these demo
> projects.

I am running it under FreeBSD and I think it has been working under
Solaris as well. Not sure about Linux, but I think some people were
using it.

> Perhaps the best thing would be for me to document how to compile lwip as
> a self initializing shared library, and let people do it themselves for
> their own projects if they think it's helpful.

If possible, a Makefile would probably be good to have as well.

/adam
-- 
Adam Dunkels <address@hidden>
http://www.sics.se/~adam/