Re: [boost] [context review] Several Questions

Subject: Re: [boost] [context review] Several Questions
From: Artyom (artyomtnk_at_[hidden])
Date: 2011-03-22 04:54:27

> 
> > > You can always fall-back to ucontext if  assembly version is  not 
provided.
> > > 
> > > I think it would be very  useful.  Because different parts of program
> > > may required different   contexts and inability to use two of them
> > > in same executable is  quite  problematic.
> > 
> > the problem is that it is unlikely  that I can implement  fcontext for all 
> >platforms and
> >  ucontext is not available for some platforms (for  instance ARM - I know 
> >glibc-ports
> > but you don't have always the possiblity to   patch/recompile the C-lib).
> > that means on some systems   boost::ucontext<>/boost::fcontext<> may
> > not be available.  I've some  doubt that this is acceptable.
> > 
> 
> The point is that  my may provide something like that:
> 
> boost::context<>                          // some  default, fcontext if 
>avalible 
>
> otherwise  ucontext
> boost::context<ucontext_with_fallback>   // ucontext,  unless available 
>fallback 
>
> to  fcontext
> boost::context<fcontext_with_fallback>   // fcontext,  unless available 
>fallback 
>
> to  ucontext
> boost::context<ucontext>                  // ucontext, fail to compile if not 
> available
> boost::context<fcontext>                  // fcontext, fail to compile if not 
> available
> 
> 

Or other option may be create:

a) boost::abstract_context and all ucontext, fcontext, fiber_context
   that is to be implemented in terms of abstract context

   So all changed would be binary compatible

b) make boost::context use pimpl ideom so all details are hidden behind
   the scenes in the sources so switching Xcontext would not change
   the ABI of the library.

Artyom