Setup basic layout system

- add Enter event bindings
- Add some more window bindings.

src/xcb/types.ml

@@ -68,6 +68,31 @@ module Events = struct
     let from ptr = Ctypes.from_voidp typ (to_voidp ptr)
     let window ptr = getf !@ptr window
   end
+
+  module Enter = struct
+    open Ctypes
+
+    type t
+
+    let typ : t structure typ = structure "xcb_enter_notify_event_t"
+    let response_type = field typ "response_type" uint8_t
+    let detail = field typ "detail" uint8_t
+    let sequence = field typ "sequence" uint16_t
+    let time = field typ "time" uint32_t
+    let root = field typ "root" Window.typ
+    let event = field typ "event" Window.typ
+    let child = field typ "child" Window.typ
+    let root_x = field typ "root_x" int16_t
+    let root_y = field typ "root_y" int16_t
+    let event_x = field typ "event_x" int16_t
+    let event_y = field typ "event_y" int16_t
+    let state = field typ "state" uint16_t
+    let mode = field typ "mode" uint8_t
+    let same_screen = field typ "same_screen_focus" uint8_t
+    let () = seal typ
+    let from ptr = Ctypes.from_voidp typ (to_voidp ptr)
+    let window ptr = getf !@ptr event
+  end
 end
 
 module Client_message = struct
@@ -205,22 +230,7 @@ typedef struct xcb_map_notify_event_t {
 /**
  * @brief xcb_enter_notify_event_t
  **/
-typedef struct xcb_enter_notify_event_t {
-    uint8_t         response_type;
-    uint8_t         detail;
-    uint16_t        sequence;
-    xcb_timestamp_t time;
-    xcb_window_t    root;
-    xcb_window_t    event;
-    xcb_window_t    child;
-    int16_t         root_x;
-    int16_t         root_y;
-    int16_t         event_x;
-    int16_t         event_y;
-    uint16_t        state;
-    uint8_t         mode;
-    uint8_t         same_screen_focus;
-} xcb_enter_notify_event_t;
+
 
 
 typedef xcb_enter_notify_event_t xcb_leave_notify_event_t;