Re: [libcvd-members] gvars3 Makefile.in configure configure.ac gvars...

[Georg Klein]

On Wed, 20 Feb 2008, Edward Rosten wrote:

> On Wed, 20 Feb 2008, Georg Klein wrote:
>
> > Nice.
> >
> > The whole global-initialised-in-a-library thing does seem rather unsafe 
> > when other classes use it in a constructor!
>
> True. I don't know exactly what the best solution is. Something to do with 
> singleton classes.

GVars2 had no globals defined in the library, so that you could define 
them in main.cc, in the order they need. Wherever they live, all 
inter-dependent globals should live in one translation unit, and that's 
what you've done in gvars3's inst.cc, but it doesn't work (portably) when 
I have other global classes which call GUI in their constructors.

A trivial fix would be a configure flag which excludes inst.cc from the 
library. This would fix all of my problems. Unless you're on a configure 
editing buzz, I'll get around to doing this some time soon.

> Not to mention the entire thread safety thing...
>
> There's two solutions to that as far as I can see.
>
> One is to put locks around the whole GVars3 database.
>
> The other is to have all widgets sets operate using their own private 
> string-tring map. Every so often, you will have to call a synchronize method 
> which will synchronize the GVars database with the private map.
>
> The second version is nice because it keeps gvars fast and you know that in 
> your main loop, things aren't going to change from under you.

(Shrug)
I don't use any of the widget sets! I suspect there's probably a lot of 
stuff which no-one uses anymore in there. For example, IIRC headless was 
requested by Ethan, but I think he uses his own thing now instead of gvars?