Re: Seg Fault on NULL strlen

[Steve & Patti Getzinger <psatg bluemarble net>]

Steve & Patti Getzinger wrote:

> Patrice St-Gelais wrote:
>
> > Hi,
> >
> > Check if "entry2" is defined the first time "on_entry1_changed" is 
> > executed.
> >
> > Maybe the callback is activated when you initialize the value of entry1,
> > before creating entry2, or something like this.
> >
> > If it's the case, inserting a test to get out of the callback if 
> > entry2 is
> > NULL, before casting it with GTK_EDITABLE, would solve the seg 
> > fault.  If I
> > understand your code and your explanation, "entry1" shouldn't be NULL at
> > this point, and should be equal to "editable" because 
> > "on_entry1_changed" is
> > connected to "entry1".
> >
> > Regards,
> >
> > Patrice St-Gelais
> > ________________________________
> >
> > Steve & Patti Getzinger a écrit :
> >
> >  
> >
> > > I am attempting to set sensitivity based on entries in 3 entry 
> > > boxes. So
> > > basically the first is easy. I am hitting a func on changed of 
> > > entry1 in
> > > the func I am doing an
> > >
> > >   
> > >
> > > > void
> > > > on_entry1_changed                (GtkEditable     *editable,
> > > >                                        gpointer         user_data)
> > > > {
> > > >  if(strlen(gtk_editable_get_chars(GTK_EDITABLE(entry1),0,-1)) > 7)
> > > >        {
> > > >
> > > > if(strlen(gtk_editable_get_chars(GTK_EDITABLE(entry2),0,-1)) > 0)
> > > >     
> > > >                        {
> > > >                        gtk_widget_set_sensitive (button1, TRUE);
> > > >                        }
> > > >        }else{
> > > >                gtk_widget_set_sensitive (button1, FALSE);
> > > >        }
> > > > }
> > > >     
> > >
> > > With this config it seg faults with:
> > >
> > >   
> > >
> > > > (gdiald:16598): GLib-GObject-WARNING **: invalid cast from (NULL)
> > > > pointer to `GtkEditable'
> > > >
> > > > (gdiald:16598): Gtk-CRITICAL **: file gtkeditable.c: line 125
> > > > (gtk_editable_get_chars): assertion `GTK_IS_EDITABLE (editable)' 
> > > > failed
> > > > Segmentation fault
> > > >     
> > >
> > > I am assuming strlen returns NULL if there has been no entry made in
> > > entry2. How do I get around this one?
> > >
> > > TIA
> > > Steve
> > >
> > >   
> Signal connects all are listed at the end of window configs so entry2 
> is already created. Is there a way for me to tap the entries involved 
> and do an if based on changed? I am not controlling the order entries 
> are made so I need to be able to tap all 3 as all three need entries. 
> This way if it has not been touched (changed) we exit the func with a 
> false setting for sensitivity. If it has we check for size of entry 
> and progress.
>
> TIA
> Steve
>
> _______________________________________________

I recently added:

if(gtk_editable_get_chars(GTK_EDITABLE(entry2),0,1) !='\0')

which stops the seg fault but still get editable is not editable error. 
I have change on entry2 set to hit the changed func of entry1 so even if 
the error is thrown while entering in entry1 when I switch to entering 
in entry2 and entery is above NULL shouldn't it possibly recognize it? 
What do I need to look for that makes entry2 seen as editable? Why is 
NULL not a valid pointer? How do I get around this?

TIA
Steve