CTK screen drawing service interface
diff --git a/contiki/ctk/ctk-draw.c b/contiki/ctk/ctk-draw.c
new file mode 100644
index 0000000..cc08b2b
--- /dev/null
+++ b/contiki/ctk/ctk-draw.c
@@ -0,0 +1,155 @@
+
+#include "ek-service.h"
+
+#include "ctk-draw.h"
+#include "ctk.h"
+
+#include "ctk-draw-service.h"
+
+
+unsigned char ctk_draw_windowborder_width,
+  ctk_draw_windowborder_height,
+  ctk_draw_windowtitle_height;
+
+EK_SERVICE(service, CTK_DRAW_SERVICE_NAME);
+
+/*---------------------------------------------------------------------------*/
+static struct ctk_draw_service_interface *
+find_interface(void)
+{
+  struct ctk_draw_service_interface *interface;
+  interface = (struct ctk_draw_service_interface *)ek_service_state(&service);
+  if(interface != NULL &&
+     interface->version == CTK_DRAW_SERVICE_VERSION) {
+    return interface;
+  } else {
+    return NULL;
+  }
+}
+/*---------------------------------------------------------------------------*/
+void
+ctk_draw_init(void)
+{
+  struct ctk_draw_service_interface *interface;
+  
+  if((interface = find_interface()) != NULL) {   
+    interface->draw_init();
+    ctk_draw_windowborder_width = interface->windowborder_width;
+    ctk_draw_windowborder_height = interface->windowborder_height;
+    ctk_draw_windowtitle_height = interface->windowtitle_height;
+  }
+}
+/*---------------------------------------------------------------------------*/
+void
+ctk_draw_clear(unsigned char clipy1, unsigned char clipy2)
+{
+  struct ctk_draw_service_interface *interface;
+  
+  if((interface = find_interface()) != NULL) {   
+    interface->draw_clear(clipy1, clipy2);
+  }
+}
+/*---------------------------------------------------------------------------*/
+void
+ctk_draw_clear_window(struct ctk_window *window,
+		      unsigned char focus,
+		      unsigned char clipy1,
+		      unsigned char clipy2)
+{
+  struct ctk_draw_service_interface *interface;
+  
+  if((interface = find_interface()) != NULL) {   
+    interface->draw_clear_window(window, focus, clipy1, clipy2);
+  }
+}
+/*---------------------------------------------------------------------------*/
+void
+ctk_draw_window(struct ctk_window *window,
+		unsigned char focus,
+		unsigned char clipy1,
+		unsigned char clipy2)
+{
+  struct ctk_draw_service_interface *interface;
+  
+  if((interface = find_interface()) != NULL) {   
+    interface->draw_window(window, focus, clipy1, clipy2);
+  }
+}
+/*---------------------------------------------------------------------------*/
+void
+ctk_draw_dialog(struct ctk_window *dialog)
+{
+  struct ctk_draw_service_interface *interface;
+  
+  if((interface = find_interface()) != NULL) {   
+    interface->draw_dialog(dialog);
+  }
+}
+/*---------------------------------------------------------------------------*/
+void
+ctk_draw_widget(struct ctk_widget *widget,
+		unsigned char focus,
+		unsigned char clipy1,
+		unsigned char clipy2)
+{
+  struct ctk_draw_service_interface *interface;
+  
+  if((interface = find_interface()) != NULL) {   
+    interface->draw_widget(widget, focus, clipy1, clipy2);
+  }
+}
+/*---------------------------------------------------------------------------*/
+void
+ctk_draw_menus(struct ctk_menus *menus)
+{
+  struct ctk_draw_service_interface *interface;
+  
+  if((interface = find_interface()) != NULL) {   
+    interface->draw_menus(menus);
+  }
+}
+/*---------------------------------------------------------------------------*/
+unsigned char
+ctk_draw_width(void)
+{
+  struct ctk_draw_service_interface *interface;
+  
+  if((interface = find_interface()) != NULL) {   
+    return interface->width();
+  }
+  return 0;
+}
+/*---------------------------------------------------------------------------*/
+unsigned char
+ctk_draw_height(void)
+{
+  struct ctk_draw_service_interface *interface;
+  
+  if((interface = find_interface()) != NULL) {   
+    return interface->height();
+  }
+  return 0;
+}
+/*---------------------------------------------------------------------------*/
+unsigned short
+ctk_mouse_xtoc(unsigned short x)
+{
+  struct ctk_draw_service_interface *interface;
+  
+  if((interface = find_interface()) != NULL) {   
+    return interface->mouse_xtoc(x);
+  }
+  return 0;
+}
+/*---------------------------------------------------------------------------*/
+unsigned short
+ctk_mouse_ytoc(unsigned short y)
+{
+  struct ctk_draw_service_interface *interface;
+  
+  if((interface = find_interface()) != NULL) {   
+    return interface->mouse_ytoc(y);
+  }
+  return 0;
+}
+/*---------------------------------------------------------------------------*/