Re: [Gnash-commit] /srv/bzr/gnash/avm2 r9685: Fix segfault caused by null objects in the scope stack.

[strk]

On Sat, Nov 15, 2008 at 09:16:39PM +0800, Tom Stellard wrote:

> So, what I should be doing is something like:
> 
> prop =getProperty();
> if(!prop)
>     log_aserror();
> 
> pushStack(prop);
> 
> and if I try to pass a NULL value to pushStack, it should abort.  What
> is the preferred way to abort?  Should I throw an exception?

I usually use an assertion, like:

        pushStack(as_object* o) { assert(o); ... }

So you can drop the additional check at compile time
when you're pretty sure there's no caller passing NULL.
Recently I also started using a PARANOIA_LEVEL macro, like in:

#if PARANOIA_LEVEL > 1
        assert(o);
#endif

As for the as_error, wrap it always in IF_VERBOSE_ASCODING_ERRORS
so any error can also be disabled at compile time.
Still, you don't want to abort if user passes a NULL property,
so you'd do something like:


        prop = getProperty();
        if ( !prop )
        {
                IF_VERBOSE_ASCODING_ERRORS(
                log_aserror(_("..."), ...);
                );
                return;
        }
        pushStack(prop);

--strk;