Make objects properly inherit signals from classes

Signed-off-by: Uli Schlachter <psychon@znc.in>

common/array.h

@@ -34,6 +34,13 @@
         int len, size;                                                      \
     } pfx##_array_t;
 
+#define ARRAY_TYPE_EXTRA(type_t, pfx, extra)                                \
+    typedef struct pfx##_array_t {                                          \
+        type_t *tab;                                                        \
+        int len, size;                                                      \
+        extra;                                                              \
+    } pfx##_array_t;
+
 #define foreach(var, array) \
     for(int __foreach_index_##var = 0; \
         __foreach_index_##var < (array).len; \

common/luaclass.c

@@ -249,14 +249,8 @@ luaA_class_setup(lua_State *L, lua_class_t *class,
 
     signal_add(&class->signals, "new");
 
-    /** @todo This is ugly :/ */
-    /* Copy all signals from the parent */
     if (parent)
-        foreach(sig, parent->signals)
-        {
-            signal_t s = { .id = sig->id };
-            signal_array_insert(&class->signals, s);
-        }
+        class->signals.inherits_from = &parent->signals;
 
     lua_class_array_append(&luaA_classes, class);
 }

common/luaobject.h

@@ -175,13 +175,7 @@ int luaA_object_emit_signal_simple(lua_State *);
         lua_setmetatable(L, -2);                                               \
         luaA_setuservalue(L, -2);                                              \
         lua_pushvalue(L, -1);                                                  \
-        /** @todo This is wrong we shouldn't copy the existing signals from */ \
-        /* the class, but I'm too lazy for doing this correctly right now. */  \
-        foreach(sig, (lua_class).signals)                                      \
-        {                                                                      \
-            signal_t s = { .id = sig->id };                                    \
-            signal_array_insert(&p->signals, s);                               \
-        }                                                                      \
+        p->signals.inherits_from = &(lua_class).signals;                       \
         luaA_class_emit_signal(L, &(lua_class), "new", 1);                     \
         return p;                                                              \
     }

common/signal.h

@@ -46,13 +46,37 @@ signal_wipe(signal_t *sig)
     cptr_array_wipe(&sig->sigfuncs);
 }
 
-DO_BARRAY(signal_t, signal, signal_wipe, signal_cmp)
+ARRAY_TYPE_EXTRA(signal_t, signal, struct signal_array_t *inherits_from)
+BARRAY_FUNCS(signal_t, signal, signal_wipe, signal_cmp)
 
 static inline signal_t *
 signal_array_getbyid(signal_array_t *arr, unsigned long id)
 {
     signal_t sig = { .id = id };
-    return signal_array_lookup(arr, &sig);
+    signal_t *result;
+
+    result = signal_array_lookup(arr, &sig);
+    if(result)
+        return result;
+
+    /* The signal doesn't exist yet. Check if some of our inherits_from have the
+     * signal and if yes, add it.
+     */
+    signal_array_t *inherit = arr->inherits_from;
+    while(inherit != NULL)
+    {
+        if(signal_array_lookup(inherit, &sig))
+            break;
+        inherit = inherit->inherits_from;
+    }
+    if(inherit)
+    {
+        /* Add the signal to this array to pretend it always existed */
+        signal_array_insert(arr, sig);
+        result = signal_array_lookup(arr, &sig);
+        assert(result != NULL);
+    }
+    return result;
 }
 
 /** Add a signal to a signal array.