[Spice-devel] [RFC PATCH] initialize global images at load time

[Frediano Ziglio]

> 
> Hi,
> 
> On Fri, Feb 26, 2016 at 10:37:21AM +0000, Frediano Ziglio wrote:
> > This make sure these stuff are initialized without using runtime
> > resources.
> > Also make sure stuff are initialize really earlier.
> >
> > Signed-off-by: Frediano Ziglio <fziglio at redhat.com>
> > ---
> >  server/red-dispatcher.c | 13 ++++++-------
> >  1 file changed, 6 insertions(+), 7 deletions(-)
> >
> > diff --git a/server/red-dispatcher.c b/server/red-dispatcher.c
> > index c2ca6b6..d09d56d 100644
> > --- a/server/red-dispatcher.c
> > +++ b/server/red-dispatcher.c
> > @@ -902,6 +902,12 @@ void red_dispatcher_async_complete(struct
> > RedDispatcher *dispatcher,
> >      free(async_command);
> >  }
> >
> > +static void __attribute__((constructor)) red_dispatcher_global_init(void)
> > +{
> > +    quic_init();
> > +    sw_canvas_init();
> > +}
> 
> We could have a define for it in spice-common and use it in a few more
> places I think. Also, it seems to be gcc specific so a #define could
> help dealing with other compilers.
> 
> 
> Cheers,
>   toso
> 

Looks like this could be a solution

http://stackoverflow.com/questions/1113409/attribute-constructor-equivalent-in-vc

constructor attribute is implemented in gcc and clang.
Static initialization is common in other languages (C++ and Java for instance) so
object files have a standard (for each architecture/compiler) to specify it.
Sun compiler have some #pragma (init/fini).
Which type of compilers are we addressing?

I think a SPICE_CONSTRUCTOR_FUNCTION(function_name) could work.
It's possible (if needed) to define similar macro for destruction (actually better
than calling atexit in a library/shared object).

Frediano

> > +
> >  void red_dispatcher_init(QXLInstance *qxl)
> >  {
> >      RedDispatcher *red_dispatcher;
> > @@ -911,13 +917,6 @@ void red_dispatcher_init(QXLInstance *qxl)
> >      spice_return_if_fail(qxl != NULL);
> >      spice_return_if_fail(qxl->st->dispatcher == NULL);
> >  
> > -    static gsize initialized = FALSE;
> > -    if (g_once_init_enter(&initialized)) {
> > -        quic_init();
> > -        sw_canvas_init();
> > -        g_once_init_leave(&initialized, TRUE);
> > -    }
> > -
> >      red_dispatcher = spice_new0(RedDispatcher, 1);
> >      red_dispatcher->qxl = qxl;
> >      dispatcher_init(&red_dispatcher->dispatcher, RED_WORKER_MESSAGE_COUNT,
> >      NULL);