callbacks: Optimize cairo logic for Gtk 3

With Gtk 3, we don't need to implement the funtion
gdk_cairo_surface_create_from_pixbuf() ourselves, as it is
available there. So, just call the right function.

Also, with Gtk 3.22 and above, the old way of calling
gdk_cairo_create() is obsolete, as all windows already have
it. So, instead, just instance it.

That supresses a deprecated function warning:

callbacks.c:604:5: warning: ‘gdk_cairo_create’ is deprecated: Use 'gdk_window_begin_draw_frame() and gdk_drawing_context_get_cairo_context()' instead [-Wdeprecated-declarations]
     cr = gdk_cairo_create(window);
     ^~
In file included from /usr/include/gtk-3.0/gdk/gdk.h:33,
                 from /usr/include/gtk-3.0/gtk/gtk.h:30,
                 from v4l.h:24,
                 from callbacks.h:4,
                 from callbacks.c:1:
/usr/include/gtk-3.0/gdk/gdkcairo.h:35:12: note: declared here
 cairo_t  * gdk_cairo_create             (GdkWindow          *window);
            ^~~~~~~~~~~~~~~~

While here, add a missing surface destroy in order to avoid
possible memory leaks.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

0 files changed, 0 insertions, 0 deletions