Re: Gtk2::ImageView memory issue

[muppet <scott asofyet org>]

On Mar 6, 2009, at 5:40 PM, Jeffrey Ratcliffe wrote:

> 2009/3/6 Torsten Schoenfeld <kaffeetisch gmx de>:
> > GBoxed descendants have their own memory management infrastructure  
> > and thus
> > also their own typemap variants: for functions returning newly  
> > constructed
> > instances of GBoxed descendants, use the _own typemap variant.  Then,
>
> I've had to write code to convert the GBox struct to a hash and back
> again - e.g.
>
> static SV *
> newSVGdkPixbufDrawCache (GdkPixbufDrawCache * cache)
> {
>  HV * hv = newHV();
>  hv_store (hv, "last_pixbuf", 11, newSVGdkPixbuf (cache- 
> >last_pixbuf), 0);
>  hv_store (hv, "old", 3, newSVGdkPixbufDrawOpts (&cache->old), 0);
>  hv_store (hv, "check_size", 10, newSViv (cache->check_size), 0);
>  return newRV_noinc ((SV *) hv);
> }
>
> Is the _own variant useful here?

No.  _own is for when your perl wrapper will hold onto the actual  
boxed object.  This is what the default wrappers do.  You are  
converting the boxed object from a C struct to a native perl object  
(the hash) and back, so you don't need to hold on to the C object,  
therefore, you don't need _own.


> How can I test that the _free method is being called?

Simplest is to wrap it:


static void
wrap_gdk_pixbuf_draw_cache_free (void * the_thing)
{
    g_print ("OMG I'M ABOUT TO FREE A GdkPixbufDrawCache AT %p\n",  
the_thing);
    gdk_pixbuf_draw_cache_free (the_thing);
}


Then register wrap_gdk_pixbuf_draw_cache_free () as the destroy  
function instead of gdk_pixbuf_draw_cache_free() and watch for the  
messages on stdout.


--
The one difference between Dali and a crazy man is very simple: Dali  
is not crazy at all.
  -- Salvador Dali