mouse: Add property miss handler.

Just like luaobject has, but for "static" classes.

mouse.c

@@ -33,11 +33,15 @@
 #include "math.h"
 #include "common/util.h"
 #include "common/xutil.h"
+#include "common/luaclass.h"
 #include "globalconf.h"
 #include "objects/client.h"
 #include "objects/drawin.h"
 #include "objects/screen.h"
 
+static int miss_index_handler    = LUA_REFNIL;
+static int miss_newindex_handler = LUA_REFNIL;
+
 /** Mouse library.
  *
  * @table mouse
@@ -119,6 +123,39 @@ mouse_warp_pointer(xcb_window_t window, int16_t x, int16_t y)
                      0, 0, 0, 0, x, y);
 }
 
+/**
+ * Allow the a Lua handler to be implemented for custom properties and
+ * functions.
+ * \param L A lua state
+ * \param handler A function on the LUA_REGISTRYINDEX
+ */
+static int
+luaA_mouse_call_handler(lua_State *L, int handler)
+{
+    int nargs = lua_gettop(L);
+
+    /* Push error handling function and move it before args */
+    lua_pushcfunction(L, luaA_dofunction_error);
+    lua_insert(L, - nargs - 1);
+    int error_func_pos = 1;
+
+    /* push function and move it before args */
+    lua_rawgeti(L, LUA_REGISTRYINDEX, handler);
+    lua_insert(L, - nargs - 1);
+
+    if(lua_pcall(L, nargs, LUA_MULTRET, error_func_pos))
+    {
+        warn("%s", lua_tostring(L, -1));
+        /* Remove error function and error string */
+        lua_pop(L, 2);
+        return 0;
+    }
+    /* Remove error function */
+    lua_remove(L, error_func_pos);
+
+    return lua_gettop(L);
+}
+
 /** Mouse library.
  * \param L The Lua VM state.
  * \return The number of elements pushed on stack.
@@ -133,8 +170,13 @@ luaA_mouse_index(lua_State *L)
     int16_t mouse_x, mouse_y;
 
     /* attr is not "screen"?! */
-    if (A_STRNEQ(attr, "screen"))
+    if (A_STRNEQ(attr, "screen")) {
-        return luaA_default_index(L);
+        if (miss_index_handler != LUA_REFNIL) {
+            return luaA_mouse_call_handler(L, miss_index_handler);
+        }
+        else
+            return luaA_default_index(L);
+    }
 
     if (!mouse_query_pointer_root(&mouse_x, &mouse_y, NULL, NULL))
     {
@@ -162,8 +204,14 @@ luaA_mouse_newindex(lua_State *L)
     const char *attr = luaL_checkstring(L, 2);
     screen_t *screen;
 
-    if (A_STRNEQ(attr, "screen"))
+    if (A_STRNEQ(attr, "screen")) {
-        return luaA_default_newindex(L);
+        /* Call the lua mouse property handler */
+        if (miss_newindex_handler != LUA_REFNIL) {
+            return luaA_mouse_call_handler(L, miss_newindex_handler);
+        }
+        else
+            return luaA_default_newindex(L);
+    }
 
     screen = luaA_checkscreen(L, 3);
     mouse_warp_pointer(globalconf.screen->root, screen->geometry.x, screen->geometry.y);
@@ -271,12 +319,32 @@ luaA_mouse_object_under_pointer(lua_State *L)
     return 0;
 }
 
+/**
+ * Add a custom property handler (getter).
+ */
+static int
+luaA_mouse_set_index_miss_handler(lua_State *L)
+{
+    return luaA_registerfct(L, 1, &miss_index_handler);
+}
+
+/**
+ * Add a custom property handler (setter).
+ */
+static int
+luaA_mouse_set_newindex_miss_handler(lua_State *L)
+{
+    return luaA_registerfct(L, 1, &miss_newindex_handler);
+}
+
 const struct luaL_Reg awesome_mouse_methods[] =
 {
     { "__index", luaA_mouse_index },
     { "__newindex", luaA_mouse_newindex },
     { "coords", luaA_mouse_coords },
     { "object_under_pointer", luaA_mouse_object_under_pointer },
+    { "set_index_miss_handler", luaA_mouse_set_index_miss_handler},
+    { "set_newindex_miss_handler", luaA_mouse_set_newindex_miss_handler},
     { NULL, NULL }
 };
 const struct luaL_Reg awesome_mouse_meta[] =