Crash when editing nickname

[Henrik Brautaset Aronsen]

I can confirm that Dirk's patch works.  Amit, maybe you could do a 
couple of additional improvements:

- Disable the Apply button until there is something to apply
- Don't close the nickname window after deleting a nickname

Cheers,
Henrik

Amit Chaudhuri wrote:
> Hi Henrik,
>
> thanks for catching.
>
> Interestingly, I can't reproduce exactly the same way, but was able to 
> crash if I simply fail to edit anything and go straight for "Apply".
>
> Dirk,
>
> the fix you mention does catch it.  I had that covered in a call to 
> "clear down" function from edit_dc_nicknames in an earlier version, 
> but I "rationalised" it out somewhere along the way.  Problem is (as 
> you clearly worked out) the dereference of holdnicknames when it 
> points to null.  This happens if no edits take place.
> The code path back through cell_edited_cb is where holdnickname list 
> entries are created.
>
> Regards,
>
> Amit
>
>
> On Sat, Jan 19, 2013 at 10:05 PM, Dirk Hohndel <dirk at hohndel.org 
> <mailto:dirk at hohndel.org>> wrote:
>
>     Henrik Brautaset Aronsen <subsurface at henrik.synth.no
>     <mailto:subsurface at henrik.synth.no>> writes:
>
>     > 1) Open the nickname list (must have 2 or more entries)
>     > 2) Delete one of the entries (The list window closes?!)
>     > 3) Re-open the nickname list
>     > 4) Edit a nickname and press Apply
>     >
>     > *BOOM*
>     >
>     > Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
>     > 0   subsurface                        0x0000000103adb303
>     > edit_dc_nicknames + 2227 (gtk-gui.c:1274)
>     > 1   libgobject-2.0.0.dylib            0x000000010474ebc4
>     > g_closure_invoke + 308
>
>     This seems to fix it.
>
>     Amit, can you confirm that this is a smart way to address the
>     issue (I'm
>     not 100% certain how the flow is supposed to work in this case -
>     but it
>     seems to work with this change)
>
>     Thanks
>
>     /D
>
>     diff --git a/gtk-gui.c b/gtk-gui.c
>     index 7a8f10c..29a77b6 100644
>     --- a/gtk-gui.c
>     +++ b/gtk-gui.c
>     @@ -1271,7 +1271,7 @@ static void edit_dc_nicknames(GtkWidget *w,
>     gpointer data)
>                             }
>                             gtk_widget_destroy(confirm);
>                     }
>     -               if (res == GTK_RESPONSE_APPLY &&
>     holdnicknames->model != NULL ) {
>     +               if (res == GTK_RESPONSE_APPLY && holdnicknames &&
>     holdnicknames->model != NULL ) {
>                             struct device_info * walk = holdnicknames;
>                             struct device_info * release = holdnicknames;
>                             struct device_info * track =
>     holdnicknames->next;
>
>
>