[g-a-devel]Re: yet another NULL pointer indirection ...

["Padraig O'Briain" <Padraig Obriain Sun COM>]

Micheal,

I have just done a commit which should fix this problem.

I have checked everty list pointer usage and made another copule of changes so 
we should not have any more of this sort of p[roblem (I hope).

Padraig

> Subject: yet another NULL pointer indirection ...
> To: "Padraig O'Briain" <Padraig Obriain sun com>
> Cc: accessibility mailing list <gnome-accessibility-devel gnome org>
> Content-Transfer-Encoding: 7bit
> Mime-Version: 1.0
> 
> This is really bad news,
> 
> 	I find it hard to believe that there are so many un-checked NULL
> pointer dereferences going on in gail; is it possible that some-one
> could audit every list pointer usage - a grep on GList would be good.
> 
> 	This is the latest:
> 
> (gdb) bt
> #0  get_image_from_button (button=0x80839f8) at gailbutton.c:588
> #1  0x40a72700 in gail_button_get_image_description (image=0x8134860) at
> gailbutton.c:611
> #2  0x40485646 in atk_image_get_image_description (image=0x8134860) at
> atkimage.c:60
> #3  0x40aaff75 in impl__get_imageDescription (servant=0x8135264,
> ev=0xbfffea80) at image.c:109
> #4  0x40abc92f in
> _ORBIT_skel_small_Accessibility_Image__get_imageDescription
> (_o_servant=0x8135264, _o_retval=0xbfffe960, _o_args=0x0, 
>     _o_ctx=0xbfffe9b0, _o_ev=0xbfffea80,
> _impl__get_imageDescription=0x40aaff0c <impl__get_imageDescription>) at
> Accessibility-skels.c:776
> #5  0x4054d498 in ORBit_POAObject_invoke (pobj=0x8135298,
> ret=0xbfffe960, args=0x0, ctx=0xbfffe9b0, data=0xbfffea20,
> ev=0xbfffea80) at poa.c:891
> #6  0x405501e3 in ORBit_OAObject_invoke (adaptor_obj=0x8135298,
> ret=0xbfffe960, args=0x0, ctx=0xbfffe9b0, data=0xbfffea20,
> ev=0xbfffea80)
>     at orbit-adaptor.c:116
> #7  0x40541106 in ORBit_small_invoke_adaptor (adaptor_obj=0x8135298,
> recv_buffer=0x8113cc0, m_data=0x40acdc70, data=0xbfffea20,
> ev=0xbfffea80)
>     at orbit-small.c:772
> #8  0x4054d953 in ORBit_POAObject_handle_request (pobj=0x8135298,
> opname=0x813cfb8 "_get_imageDescription", ret=0x0, args=0x0, ctx=0x0, 
>     recv_buffer=0x8113cc0, ev=0xbfffea80) at poa.c:1085
> #9  0x4054db86 in ORBit_POA_handle_request (poa=0x8061fc0,
> recv_buffer=0x8113cc0, objkey=0x8113cd8) at poa.c:1172
> #10 0x4055016e in ORBit_handle_request (orb=0x8061f40,
> recv_buffer=0x8113cc0) at orbit-adaptor.c:79
> #11 0x4053c91a in giop_connection_handle_input (lcnx=0x8121c00) at
> giop-recv-buffer.c:951
> #12 0x4059253b in linc_connection_io_handler (gioc=0x0,
> condition=G_IO_IN, data=0x8121c00) at linc-connection.c:840
> #13 0x40593e60 in linc_source_dispatch (source=0x8121c68,
> callback=0x405924d0 <linc_connection_io_handler>, user_data=0x8121c00)
> at linc-source.c:56
> #14 0x4060b696 in g_main_dispatch (context=0x805dd90) at gmain.c:1617
> #15 0x4060c4ad in g_main_context_dispatch (context=0x805dd90) at
> gmain.c:2161
> #16 0x4060c840 in g_main_context_iterate (context=0x805dd90, block=1,
> dispatch=1, self=0x8054e80) at gmain.c:2242
> #17 0x4060cee6 in g_main_loop_run (loop=0x811b0d0) at gmain.c:2462
> #18 0x400ebec2 in bonobo_main () at bonobo-main.c:290
> #19 0x0804b1c6 in main (argc=1, argv=0xbffff6b4) at test-ui.c:485
> #20 0x40699306 in __libc_start_main (main=0x804a0d0 <main>, argc=1,
> ubp_av=0xbffff6b4, init=0x80496b8 <_init>, fini=0x804bc30 <_fini>, 
>     rtld_fini=0x4000d2dc <_dl_fini>, stack_end=0xbffff6ac) at
> ../sysdeps/generic/libc-start.c:129
> (gdb) dir /opt/ngnome2/src/gail/gail
> Source directories searched: /opt/ngnome2/src/gail/gail:$cdir:$cwd
> (gdb) l
> 583	  if (GTK_IS_ALIGNMENT (child))
> 584	    child = gtk_bin_get_child (GTK_BIN (child));
> 585	  if (GTK_IS_BOX (child))
> 586	    {
> 587	      list = gtk_container_children (GTK_CONTAINER (child));
> 588	      if (GTK_IS_IMAGE (list->data))
> 589	        image = GTK_IMAGE (list->data);
> 590	      g_list_free (list);
> 591	    }
> 592	
> (gdb) p list
> $1 = (GList *) 0x0
> 
> 	I'd fix it instantly, but it's too much pain to go around the approval
> loop.
> 
> 	Regards,
> 
> 		Michael.
> 
> -- 
>  mmeeks gnu org  <><, Pseudo Engineer, itinerant idiot
>