degesch: get rid of repeating refcounting code

Macros aren't exactly spectacular but they work.

degesch.c

@@ -100,12 +100,43 @@ static struct config_item g_config_table[] =
 		return false;                                                          \
 	BLOCK_END
 
-static void user_unref (void *p);
+struct user;
-static void channel_unref (void *p);
+static void user_unref (struct user *self);
+
+struct channel;
+static void channel_unref (struct channel *self);
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+// We need a few reference countable objects with support
+// for both strong and weak references
 
 /// Callback just before a reference counted object is destroyed
 typedef void (*destroy_cb_fn) (void *object, void *user_data);
 
+#define REF_COUNTABLE_HEADER                                                   \
+	size_t ref_count;                   /**< Reference count                */ \
+	destroy_cb_fn on_destroy;           /**< To remove any weak references  */ \
+	void *user_data;                    /**< User data for callbacks        */
+
+#define REF_COUNTABLE_METHODS(name)                                            \
+	static struct name *                                                       \
+	name ## _ref (struct name *self)                                           \
+	{                                                                          \
+		self->ref_count++;                                                     \
+		return self;                                                           \
+	}                                                                          \
+																			   \
+	static void                                                                \
+	name ## _unref (struct name *self)                                         \
+	{                                                                          \
+		if (--self->ref_count)                                                 \
+			return;                                                            \
+		if (self->on_destroy)                                                  \
+			self->on_destroy (self, self->user_data);                          \
+		name ## _destroy (self);                                               \
+	}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 
 struct user_channel
@@ -123,9 +154,8 @@ user_channel_new (void)
 }
 
 static void
-user_channel_destroy (void *p)
+user_channel_destroy (struct user_channel *self)
 {
-	struct user_channel *self = p;
 	channel_unref (self->channel);
 	free (self);
 }
@@ -137,10 +167,7 @@ user_channel_destroy (void *p)
 
 struct user
 {
-	size_t ref_count;                   ///< Reference count
+	REF_COUNTABLE_HEADER
-
-	destroy_cb_fn on_destroy;           ///< To remove any weak references
-	void *user_data;                    ///< User data for callbacks
 
 	// TODO: eventually a reference to the server
 
@@ -162,29 +189,13 @@ user_new (void)
 static void
 user_destroy (struct user *self)
 {
-	if (self->on_destroy)
-		self->on_destroy (self, self->user_data);
-
 	free (self->nickname);
 	LIST_FOR_EACH (struct user_channel, iter, self->channels)
 		user_channel_destroy (iter);
 	free (self);
 }
 
-static struct user *
+REF_COUNTABLE_METHODS (user)
-user_ref (struct user *self)
-{
-	self->ref_count++;
-	return self;
-}
-
-static void
-user_unref (void *p)
-{
-	struct user *self = p;
-	if (!--self->ref_count)
-		user_destroy (self);
-}
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 
@@ -204,9 +215,8 @@ channel_user_new (void)
 }
 
 static void
-channel_user_destroy (void *p)
+channel_user_destroy (struct channel_user *self)
 {
-	struct channel_user *self = p;
 	user_unref (self->user);
 	free (self->modes);
 	free (self);
@@ -219,10 +229,7 @@ channel_user_destroy (void *p)
 
 struct channel
 {
-	size_t ref_count;                   ///< Reference count
+	REF_COUNTABLE_HEADER
-
-	destroy_cb_fn on_destroy;           ///< To remove any weak references
-	void *user_data;                    ///< User data for callbacks
 
 	// TODO: eventually a reference to the server
 
@@ -244,9 +251,6 @@ channel_new (void)
 static void
 channel_destroy (struct channel *self)
 {
-	if (self->on_destroy)
-		self->on_destroy (self, self->user_data);
-
 	free (self->name);
 	free (self->mode);
 	free (self->topic);
@@ -255,20 +259,7 @@ channel_destroy (struct channel *self)
 	free (self);
 }
 
-static struct channel *
+REF_COUNTABLE_METHODS (channel)
-channel_ref (struct channel *self)
-{
-	self->ref_count++;
-	return self;
-}
-
-static void
-channel_unref (void *p)
-{
-	struct channel *self = p;
-	if (!--self->ref_count)
-		channel_destroy (self);
-}
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -