XDG_decoration protocol questions

[Mariano]

I have added to my MGRX Wayland videodriver (mgrx.fgrim.com) support for the
XDG_decoration protocol to have server side window decorations.

After doing the wayland-scanner magic to generate the .h include and the 
.c glue code

Adding the include:

     #include "xdg-decoration-client-protocol.h"

Bind the global register:

     } else if (strcmp(interface, 
zxdg_decoration_manager_v1_interface.name) == 0) {
         state->zxdg_decoration_manager_v1 = wl_registry_bind(
             wl_registry, name, &zxdg_decoration_manager_v1_interface, 1);
         //fprintf(stderr, "zxdg_decoration_manager_v1 detected\n");
     }

After getting the xdg_surface get the zxdg_toplevel_decoration_v1 object 
and add the listener:

     /* if the compositor support it (like the KDE one) ask for server 
side decoration */
     if (_WGrState.zxdg_decoration_manager_v1) {
         _WGrState.zxdg_toplevel_decoration_v1 =
             zxdg_decoration_manager_v1_get_toplevel_decoration(
                 _WGrState.zxdg_decoration_manager_v1, 
_WGrState.xdg_toplevel);
zxdg_toplevel_decoration_v1_add_listener(_WGrState.zxdg_toplevel_decoration_v1,
             &zxdg_toplevel_decoration_v1_listener, &_WGrState);
     }

And declare the listener:

     static void toplevel_decoration_v1_configure(void *data,
                 struct zxdg_toplevel_decoration_v1 
*zxdg_toplevel_decoration_v1,
                 uint32_t mode)
     {
         //fprintf(stderr, "zxdg_decoration_manager_v1 mode %d\n", mode);
     }

     static const struct zxdg_toplevel_decoration_v1_listener
         zxdg_toplevel_decoration_v1_listener = {
         .configure = toplevel_decoration_v1_configure,
     };

After that you have (in KDE) your window magically server side decorated.

My questions are (thinking in servers other than KDE):

1-Can I assume the server will send the configure event even if I have not
sent a set_mode request?

2-If the mode reported by the configure event is not 2, must we need to send
a set_mode(2) request and wait for the next configure event before attaching
the first buffer to the wl_surface?

Thanks
Mariano Alvarez