X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~mdw/git/clg/blobdiff_plain/008c81d968bd0b7534bdc93841418897d6808ed1..e59b159786355b542f5036b1b40247666fe195f2:/glib/gobject.lisp

diff --git a/glib/gobject.lisp b/glib/gobject.lisp
index 0b01d2e..68ee82c 100644
--- a/glib/gobject.lisp
+++ b/glib/gobject.lisp
@@ -1,5 +1,5 @@
 ;; Common Lisp bindings for GTK+ v2.x
-;; Copyright 2000-2005 Espen S. Johnsen <espen@users.sf.net>
+;; Copyright 2000-2006 Espen S. Johnsen <espen@users.sf.net>
 ;;
 ;; Permission is hereby granted, free of charge, to any person obtaining
 ;; a copy of this software and associated documentation files (the
@@ -20,7 +20,7 @@
 ;; TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 ;; SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-;; $Id: gobject.lisp,v 1.41 2006-02-03 12:44:32 espen Exp $
+;; $Id: gobject.lisp,v 1.59 2008-11-04 03:22:23 espen Exp $
 
 (in-package "GLIB")
 
@@ -28,25 +28,41 @@ (in-package "GLIB")
 ;;;; Metaclass used for subclasses of gobject
 
 (eval-when (:compile-toplevel :load-toplevel :execute)
+;;   (push :debug-ref-counting *features*)
   (defclass gobject-class (ginstance-class)
-    ((instance-slots-p :initform nil
+    ((instance-slots-p :initform nil :reader instance-slots-p
       :documentation "Non NIL if the class has slots with instance allocation")))
 
   (defmethod validate-superclass ((class gobject-class) (super standard-class))
 ;  (subtypep (class-name super) 'gobject)
     t))
 
+(defmethod slot-unbound (metaclass (class gobject-class) (slot (eql 'ref)))
+  (assert (class-direct-superclasses class))
+  (setf (slot-value class 'ref) 
+   #?-(pkg-exists-p "glib-2.0" :atleast-version "2.10.0") '%object-ref
+   #?(pkg-exists-p "glib-2.0" :atleast-version "2.10.0")
+   ;; We do this hack instead of creating a new metaclass to avoid
+   ;; breaking backward compatibility
+   (if (subtypep (class-name class) 'initially-unowned)
+       '%object-ref-sink
+     '%object-ref)))
+
+(defmethod slot-unbound (metaclass (class gobject-class) (slot (eql 'unref)))
+  (setf (slot-value class 'unref) '%object-unref))
+
+
 (defclass direct-property-slot-definition (direct-virtual-slot-definition)
   ((pname :reader slot-definition-pname :initarg :pname)
-   (readable :initform t :reader slot-readable-p :initarg :readable)
-   (writable :initform t :reader slot-writable-p :initarg :writable)
-   (construct :initform nil :initarg :construct)))
+   (readable :reader slot-readable-p :initarg :readable)
+   (writable :reader slot-writable-p :initarg :writable)
+   (construct-only :initarg :construct-only :reader construct-only-property-p)))
 
 (defclass effective-property-slot-definition (effective-virtual-slot-definition)
   ((pname :reader slot-definition-pname :initarg :pname)
-   (readable :reader slot-readable-p :initarg :readable)
-   (writable :reader slot-writable-p :initarg :writable)
-   (construct :initarg :construct)))
+   (readable :initform t :reader slot-readable-p :initarg :readable)
+   (writable :initform t :reader slot-writable-p :initarg :writable)
+   (construct-only :initform nil :initarg :construct-only :reader construct-only-property-p)))
 
 (defclass direct-user-data-slot-definition (direct-virtual-slot-definition)
   ())
@@ -61,39 +77,37 @@ (defbinding %object-ref () pointer
 (defbinding %object-unref () nil
   (location pointer))
 
-#+glib2.8
+#?(pkg-exists-p "glib-2.0" :atleast-version "2.8.0")
 (progn
-  (defcallback toggle-ref-callback (nil (data pointer) (location pointer) (last-ref-p boolean))
+  (define-callback toggle-ref-callback nil
+      ((data pointer) (location pointer) (last-ref-p boolean))
+    (declare (ignore data))
+    #+debug-ref-counting
+    (if last-ref-p
+	(format t "Object at 0x~8,'0X has no foreign references~%" (pointer-address location))
+      (format t "Foreign reference added to object at 0x~8,'0X~%" (pointer-address location)))
     (if last-ref-p
 	(cache-instance (find-cached-instance location) t)
       (cache-instance (find-cached-instance location) nil)))
 
-  (defbinding %object-add-toggle-ref () pointer
+  (defbinding %object-add-toggle-ref (location) pointer
     (location pointer)
-    ((callback toggle-ref-callback) pointer)
+    (toggle-ref-callback callback)
     (nil null))
 
-  (defbinding %object-remove-toggle-ref () pointer
+  (defbinding %object-remove-toggle-ref (location) pointer
     (location pointer)
-    ((callback toggle-ref-callback) pointer)
+    (toggle-ref-callback callback)
     (nil null)))
 
-(defmethod reference-foreign ((class gobject-class) location)
-  (declare (ignore class))
-  (%object-ref location))
-
-(defmethod unreference-foreign ((class gobject-class) location)
-  (declare (ignore class))
-  (%object-unref location))
-
 #+debug-ref-counting
 (progn
-  (defcallback weak-ref-callback (nil (data pointer) (location pointer))
-    (format t "Object at 0x~8,'0X being finalized~%" (sap-int location)))
+  (define-callback weak-ref-callback nil ((data pointer) (location pointer))
+    (format t "Object at 0x~8,'0X (~A) being finalized~%" (pointer-address location) (type-from-number (%type-number-of-ginstance location))))
   
-  (defbinding %object-weak-ref () pointer
+  (defbinding %object-weak-ref (location) pointer
     (location pointer)
-    ((callback weak-ref-callback) pointer)
+    (weak-ref-callback callback)
     (nil null)))
 
 
@@ -123,86 +137,128 @@ (defmethod effective-slot-definition-class ((class gobject-class) &rest initargs
     (t (call-next-method))))
 
 (defmethod compute-effective-slot-definition-initargs ((class gobject-class) direct-slotds)
-  (if (typep (first direct-slotds) 'direct-property-slot-definition)
-      (nconc 
-       (list :pname (signal-name-to-string 
-		     (most-specific-slot-value direct-slotds 'pname))
-	     :readable (most-specific-slot-value direct-slotds 'readable)
-	     :writable (most-specific-slot-value direct-slotds 'writable)
-	     :construct (most-specific-slot-value direct-slotds 'construct))
+  (if (eq (slot-definition-allocation (first direct-slotds)) :property)
+      (nconc
+       (compute-most-specific-initargs direct-slotds
+        '(pname construct-only readable writable))
        (call-next-method))
     (call-next-method)))
 
 
-(defmethod initialize-internal-slot-functions ((slotd effective-property-slot-definition))
-  (let ((type (slot-definition-type slotd))
-	(pname (slot-definition-pname slotd)))
-    (when (and (not (slot-boundp slotd 'getter)) (slot-readable-p slotd))
-      (setf 
-       (slot-value slotd 'getter)
-       (let ((reader nil))
-	 #'(lambda (object)
-	     (unless reader
-	       (setq reader (reader-function type)))
-	     (let ((gvalue (gvalue-new type)))
-	       (%object-get-property object pname gvalue)
-	       (unwind-protect
-		 (funcall reader  gvalue +gvalue-value-offset+)
-		 (gvalue-free gvalue t)))))))
-    
-    (when (and (not (slot-boundp slotd 'setter)) (slot-writable-p slotd))
-      (setf 
-       (slot-value slotd 'setter)
-       (let ((writer nil))
-	 #'(lambda (value object)
-	     (unless writer
-	       (setq writer (writer-function type)))
-	     (let ((gvalue (gvalue-new type)))
-	       (funcall writer value gvalue +gvalue-value-offset+)
-	       (%object-set-property object pname gvalue)
-	       (gvalue-free gvalue t)
-	       value))))))
-
-  (call-next-method))
-
-(defmethod initialize-internal-slot-functions ((slotd effective-user-data-slot-definition))
+(defvar *ignore-setting-construct-only-property* nil)
+(declaim (special *ignore-setting-construct-only-property*))
+
+(defmethod compute-slot-reader-function ((slotd effective-property-slot-definition) &optional signal-unbound-p)
+  (declare (ignore signal-unbound-p))
+  (let* ((type (slot-definition-type slotd))
+	 (pname (slot-definition-pname slotd))
+	 (get-reader (reader-function type :ref :get))
+	 (peek-reader (reader-function type :ref :peek)))
+    #'(lambda (object)
+	(with-memory (gvalue +gvalue-size+)
+	  (%gvalue-init gvalue (find-type-number type))
+	  (%object-get-property object pname gvalue)
+	  (if (gvalue-static-p gvalue)
+	      (funcall peek-reader gvalue +gvalue-value-offset+)
+	    (funcall get-reader gvalue +gvalue-value-offset+))))))
+
+(defmethod compute-slot-writer-function :around ((slotd effective-property-slot-definition))
+  (if (construct-only-property-p slotd)
+      #'(lambda (value object)
+	  (declare (ignore value))
+	  (unless *ignore-setting-construct-only-property*
+	    (error 'unwritable-slot :name (slot-definition-name slotd) :instance object)))
+    (call-next-method)))
+
+(defmethod compute-slot-writer-function ((slotd effective-property-slot-definition))
+  (let* ((type (slot-definition-type slotd))
+	 (pname (slot-definition-pname slotd))
+	 (writer (writer-function type :temp t))
+	 (destroy (destroy-function type :temp t)))
+    #'(lambda (value object)
+	(with-memory (gvalue +gvalue-size+)
+	  (%gvalue-init gvalue (find-type-number type))
+	  (funcall writer value gvalue +gvalue-value-offset+)
+	  (%object-set-property object pname gvalue)
+	  (funcall destroy gvalue +gvalue-value-offset+))
+	value)))
+
+(defmethod slot-readable-p ((slotd effective-user-data-slot-definition))
+  (declare (ignore slotd))
+  t)
+
+(defmethod compute-slot-reader-function ((slotd effective-user-data-slot-definition) &optional signal-unbound-p)
+  (declare (ignore signal-unbound-p))
   (let ((slot-name (slot-definition-name slotd)))
-    (unless (slot-boundp slotd 'getter)
-      (setf 
-       (slot-value slotd 'getter)
-       #'(lambda (object)
-	   (prog1 (user-data object slot-name)))))
-    (unless (slot-boundp slotd 'setter)
-      (setf 
-       (slot-value slotd 'setter)
-       #'(lambda (value object)
-	   (setf (user-data object slot-name) value))))
-    (unless (slot-boundp slotd 'boundp)
-      (setf 
-       (slot-value slotd 'boundp)
-       #'(lambda (object)
-	   (user-data-p object slot-name)))))
-  (call-next-method))
-
-(defmethod shared-initialize :after ((class gobject-class) names &rest initargs)
-  (declare (ignore initargs))
-  (when (some #'(lambda (slotd)
-		  (and
-		   (eq (slot-definition-allocation slotd) :instance)
-		   (not (typep slotd 'effective-special-slot-definition))))
-	      (class-slots class))
-    (setf (slot-value class 'instance-slots-p) t)))
+    #'(lambda (object)
+	(user-data object slot-name))))
+
+(defmethod compute-slot-boundp-function ((slotd effective-user-data-slot-definition))
+  (let ((slot-name (slot-definition-name slotd)))
+    #'(lambda (object)
+	(user-data-p object slot-name))))
+
+(defmethod slot-writable-p ((slotd effective-user-data-slot-definition))
+  (declare (ignore slotd))
+  t)
+
+(defmethod compute-slot-writer-function ((slotd effective-user-data-slot-definition))
+  (let ((slot-name (slot-definition-name slotd)))
+    #'(lambda (value object)
+	(setf (user-data object slot-name) value))))
+
+(defmethod compute-slot-makunbound-function ((slotd effective-user-data-slot-definition))
+  (let ((slot-name (slot-definition-name slotd)))
+    #'(lambda (object)
+	(unset-user-data object slot-name))))
 
+(defmethod compute-slots :around ((class gobject-class))
+  (let ((slots (call-next-method)))
+    (when (some #'(lambda (slotd)
+		    (and
+		     (eq (slot-definition-allocation slotd) :instance)
+		     (not (typep slotd 'effective-special-slot-definition))))
+		slots)
+      (setf (slot-value class 'instance-slots-p) t))
+    slots))
 
 
 ;;;; Super class for all classes in the GObject type hierarchy
 
 (eval-when (:compile-toplevel :load-toplevel :execute)
   (defclass gobject (ginstance)
-    ()
+    (#+debug-ref-counting
+     (ref-count :allocation :alien :type int :reader ref-count))
     (:metaclass gobject-class)
     (:gtype "GObject")))
 
+#+debug-ref-counting
+(defmethod print-object ((instance gobject) stream)
+  (print-unreadable-object (instance stream :type t :identity nil)
+    (if (proxy-valid-p instance)
+	(format stream "at 0x~X (~D)" (pointer-address (foreign-location instance)) (ref-count instance))
+      (write-string "at \"unbound\"" stream))))
+
+
+(define-type-method reader-function ((type gobject) &key (ref :read) inlined)
+  (assert-not-inlined type inlined)
+  (ecase ref
+    ((:read :peek) (call-next-method type :ref :read))
+    (:get
+     #'(lambda (location &optional (offset 0))
+	 (let ((instance (ref-pointer location offset)))
+	   (unless (null-pointer-p instance)
+	     (multiple-value-bind (gobject new-p)
+		 (ensure-proxy-instance 'gobject instance :reference nil)
+	       (unless new-p
+		 (%object-unref instance))
+	       (setf (ref-pointer location offset) (make-pointer 0))
+	       gobject)))))))
+
+(define-type-method callback-wrapper ((type gobject) var arg form)
+  (let ((class (type-expand type)))
+    `(let ((,var (ensure-proxy-instance ',class ,arg)))
+       ,form)))
 
 (defun initial-add (object function initargs key pkey)
   (loop 
@@ -220,84 +276,102 @@ (defun initial-apply-add (object function initargs key pkey)
 	       initargs key pkey))
 
 
+(defmethod make-proxy-instance ((class gobject-class) location &rest initargs)
+  (declare (ignore location initargs))
+  (if (slot-value class 'instance-slots-p)
+      (error "Objects of class ~A has instance slots and should only be created with MAKE-INSTANCE" class)
+    (call-next-method)))
+
+(defparameter +gparameter-gvalue-offset+
+  (max (size-of 'pointer) (type-alignment '(unsigned-byte 64))))
+(defparameter +gparameter-size+
+  (+ +gparameter-gvalue-offset+ +gvalue-size+))
+
+(defmethod allocate-foreign ((object gobject) &rest initargs)
+  (let ((init-slots ())) 
+    (flet ((value-from-initargs (slotd)
+	     (loop
+	      with slot-initargs = (slot-definition-initargs slotd)
+	      for (initarg value) on initargs by #'cddr
+	      when (find initarg slot-initargs)
+	      do (return (values value t)))))
+
+    (loop 
+     for slotd in (class-slots (class-of object))
+     when (and 
+	   (eq (slot-definition-allocation slotd) :property)
+	   (construct-only-property-p slotd))
+     do (multiple-value-bind (value initarg-p) (value-from-initargs slotd)
+	  (cond
+	   (initarg-p (push (cons slotd value) init-slots))
+	   ((slot-definition-initfunction slotd)
+	    (push 
+	     (cons slotd (funcall (slot-definition-initfunction slotd)))
+	     init-slots))))))
+
+    (cond
+     (init-slots
+      (let* ((num-slots (length init-slots)))
+	(with-memory (params (* num-slots +gparameter-size+))
+          (loop
+	   with string-writer = (writer-function 'string)
+	   for (slotd . value) in init-slots
+	   as param = params then (pointer+ param +gparameter-size+)
+	   as type = (slot-definition-type slotd)
+	   as pname = (slot-definition-pname slotd)
+	   do (funcall string-writer pname param)
+	      (gvalue-init 
+	       (pointer+ param +gparameter-gvalue-offset+) type value))
+
+	  (unwind-protect
+	      (%gobject-newv (type-number-of object) num-slots params)
+	
+	    (loop
+	     with string-destroy = (destroy-function 'string)
+	     repeat num-slots
+	     as param = params then (pointer+ param +gparameter-size+)
+	     do (funcall string-destroy param)
+	        (gvalue-unset (pointer+ param +gparameter-gvalue-offset+)))))))
+     
+     (t (%gobject-new (type-number-of object))))))
+
+
+(defmethod shared-initialize ((object gobject) names &rest initargs)
+  (declare (ignore names initargs))
+  (let ((*ignore-setting-construct-only-property* t))
+    (call-next-method)))
+
 (defmethod initialize-instance :around ((object gobject) &rest initargs)
   (declare (ignore initargs))
-  (call-next-method)
-  #+debug-ref-counting(%object-weak-ref (proxy-location object))
-  #+glib2.8
-  (when (slot-value (class-of object) 'instance-slots-p)
-    (with-slots (location) object
-      (%object-add-toggle-ref location)
-      (%object-unref location))))
-
-
-(defmethod initialize-instance ((object gobject) &rest initargs)
-  (unless (slot-boundp object 'location)
-    ;; Extract initargs which we should pass directly to the GObject
-    ;; constructor
-    (let* ((slotds (class-slots (class-of object)))
-	   (args (when initargs
-		   (loop 
-		    as (key value . rest) = initargs then rest
-		    as slotd = (find-if
-				#'(lambda (slotd)
-				    (member key (slot-definition-initargs slotd)))
-				slotds)
-		    when (and (typep slotd 'effective-property-slot-definition)
-			      (slot-value slotd 'construct))
-		    collect (progn 
-			      (remf initargs key)
-			      (list 
-			       (slot-definition-pname slotd)
-			       (slot-definition-type slotd)
-			       value))
-		    while rest))))
-      (if args
-	  (let* ((string-size (size-of 'string))
-		 (string-writer (writer-function 'string))
-		 (string-destroy (destroy-function 'string))
-		 (params (allocate-memory 
-			  (* (length args) (+ string-size +gvalue-size+)))))
-	    (loop
-	     for (pname type value) in args
-	     as tmp = params then (sap+ tmp (+ string-size +gvalue-size+))
-	     do (funcall string-writer pname tmp)
-	     (gvalue-init (sap+ tmp string-size) type value))
-	    (unwind-protect
-		(setf  
-		 (slot-value object 'location) 
-		 (%gobject-newv (type-number-of object) (length args) params))
-	      (loop
-	       repeat (length args)
-	       as tmp = params then (sap+ tmp (+ string-size +gvalue-size+))
-	       do (funcall string-destroy tmp)
-	       (gvalue-unset (sap+ tmp string-size)))
-	      (deallocate-memory params)))
-	(setf  
-	 (slot-value object 'location) 
-	 (%gobject-new (type-number-of object))))))
-
-  (apply #'call-next-method object initargs))
+  (prog1
+      (call-next-method)
+    (let ((location (foreign-location object)))
+      #+debug-ref-counting(%object-weak-ref location)
+      #?(pkg-exists-p "glib-2.0" :atleast-version "2.8.0")
+      (when (slot-value (class-of object) 'instance-slots-p)
+	(%object-add-toggle-ref location)
+	(%object-unref location)))))
 
 
 (defmethod instance-finalizer ((instance gobject))
-  (let ((location (proxy-location instance)))
-    #+glib2.8
+  (let ((location (foreign-location instance)))
+    #?(pkg-exists-p "glib-2.0" :atleast-version "2.8.0")
     (if (slot-value (class-of instance) 'instance-slots-p)
 	#'(lambda ()
 	    #+debug-ref-counting
-	    (format t "Finalizing proxy for 0x~8,'0X~%" (sap-int location))
-	    (remove-cached-instance location)
+	    (format t "Finalizing proxy for 0x~8,'0X (~A)~%" 
+	     (pointer-address location) 
+	     (find-foreign-type-name (%type-number-of-ginstance location)))
 	    (%object-remove-toggle-ref location))
       #'(lambda ()
 	  #+debug-ref-counting
-	  (format t "Finalizing proxy for 0x~8,'0X~%" (sap-int location))
-	  (remove-cached-instance location)
+	  (format t "Finalizing proxy for 0x~8,'0X (~A)~%" 
+	   (pointer-address location)
+	   (find-foreign-type-name (%type-number-of-ginstance location)))
 	  (%object-unref location)))
-    #-glib2.8
+    #?-(pkg-exists-p "glib-2.0" :atleast-version "2.8.0")
     #'(lambda ()
-	(remove-cached-instance location)
-	  (%object-unref location))))
+	(%object-unref location))))
 
 
 (defbinding (%gobject-new "g_object_new") () pointer
@@ -310,6 +384,25 @@ (defbinding (%gobject-newv "g_object_newv") () pointer
   (params pointer))
 
 
+;;;; Floating references
+
+#?(pkg-exists-p "glib-2.0" :atleast-version "2.10.0")
+(progn
+  (defclass initially-unowned (gobject)
+    ()
+    (:metaclass gobject-class)
+    (:gtype "GInitiallyUnowned"))
+
+  (defbinding %object-ref-sink () pointer
+    (location pointer))
+
+  (defbinding %object-is-floating () boolean
+    (location pointer))
+
+  (defmethod initialize-instance :before ((object initially-unowned) &rest initargs)
+    (declare (ignore initargs))
+    (%object-ref-sink (foreign-location object))))
+
 
 ;;;; Property stuff
 
@@ -336,47 +429,40 @@ (defbinding object-thaw-notify () nil
 
 ;;;; User data
 
+(defgeneric (setf user-data) (data object key))
+(defgeneric user-data (object key))
+(defgeneric user-data-p (object key))
+(defgeneric unset-user-data (object key))
+
 (defbinding %object-set-qdata-full () nil
   (object gobject)
   (id quark)
-  (data unsigned-long)
-  (destroy-marshal pointer))
+  (data pointer-data)
+  (destroy-marshal callback))
 
-(defcallback user-data-destroy-func (nil (id unsigned-int))
+(define-callback user-data-destroy-callback nil ((id pointer-data))
   (destroy-user-data id))
 
-(export 'user-data-destroy-func)
-
-(defun (setf user-data) (data object key)
+(defmethod (setf user-data) (data (object gobject) key)
   (%object-set-qdata-full object (quark-intern key)
-   (register-user-data data) (callback user-data-destroy-func))
+   (register-user-data data) user-data-destroy-callback)
   data)
 
-;; deprecated
-(defun (setf object-data) (data object key &key (test #'eq))
-  (assert (eq test #'eq))
-  (setf (user-data object key) data))
-
-(defbinding %object-get-qdata () unsigned-long
+(defbinding %object-get-qdata () pointer-data
   (object gobject)		 
   (id quark))
 
-(defun user-data (object key)
+(defmethod user-data ((object gobject) key)
   (find-user-data (%object-get-qdata object (quark-intern key))))
 
-;; deprecated
-(defun object-data (object key &key (test #'eq))
-  (assert (eq test #'eq))
-  (user-data object key))
-
-(defun user-data-p (object key)
+(defmethod user-data-p ((object gobject) key)
   (user-data-exists-p (%object-get-qdata object (quark-intern key))))
 
-(defbinding %object-steal-qdata () unsigned-long
+(defbinding %object-steal-qdata () pointer-data
   (object gobject)		 
   (id quark))
 
-(defun unset-user-data (object key)
+(defmethod unset-user-data ((object gobject) key)
   (destroy-user-data (%object-steal-qdata object (quark-intern key))))
 
 
@@ -413,7 +499,14 @@ (defun query-object-class-properties (type &optional inherited-p)
 
 
 (defun default-slot-name (name)
-  (intern (substitute #\- #\_ (string-upcase (string-upcase name)))))
+  (let ((prefix-len (length (package-prefix))))
+    (intern (substitute #\- #\_
+	     (string-upcase
+	      (if (and
+		   (string-prefix-p (package-prefix) name)
+		   (char= #\- (char name prefix-len)))
+		  (subseq name (1+ prefix-len))
+		name))))))
 
 (defun default-slot-accessor (class-name slot-name type)
   (intern
@@ -452,9 +545,8 @@ (defun slot-definition-from-property (class property &optional slot-name args)
 	    '(:writable nil))
 	,@(when (not (member :readable flags))
 	    '(:readable nil))
-	,@(when (or (member :construct flags) 
-		    (member :construct-only flags))
-	    '(:construct t))
+	,@(when (member :construct-only flags)
+	    '(:construct-only t))
 	
 	;; initargs
 	,@(if (find :initarg args)
@@ -493,20 +585,30 @@ (defun slot-definitions (class properties slots)
 (defun expand-gobject-type (type forward-p options &optional (metaclass 'gobject-class))
   (let ((supers (cons (supertype type) (implements type)))
 	(class  (type-from-number type))
-	(slots (getf options :slots)))    
+	(slots (getf options :slots)))
+    (when (member nil supers)
+      (error "Got NIL as a supertype for ~A (full list: ~A).~%~
+              This shouldn't happen - is the parent type correctly registered?"
+             (find-foreign-type-name type) supers))
     `(defclass ,class ,supers
 	 ,(unless forward-p
 	    (slot-definitions class (query-object-class-properties type) slots))
 	 (:metaclass ,metaclass)
 	 (:gtype ,(register-type-as type)))))
 
-(defun gobject-dependencies (type)
+(defun gobject-dependencies (type options)
   (delete-duplicates 
    (cons
     (supertype type)
     (append 
      (type-interfaces type)
-     (mapcar #'param-value-type (query-object-class-properties type))))))
+     (mapcar #'param-value-type (query-object-class-properties type))
+     (getf options :dependencies)
+     (loop
+      for slot in (getf options :slots)
+      as type = (getf (rest slot) :type)
+      when (and type (symbolp type) (find-type-number type))
+      collect (find-type-number type))))))
 
 
 (register-derivable-type 'gobject "GObject" 'expand-gobject-type 'gobject-dependencies)
@@ -515,19 +617,19 @@ (register-derivable-type 'gobject "GObject" 'expand-gobject-type 'gobject-depend
 ;;; Pseudo type for gobject instances which have their reference count
 ;;; increased by the returning function
 
-(defmethod alien-type ((type (eql 'referenced)) &rest args)
-  (declare (ignore type args))
-  (alien-type 'gobject))
-
-(defmethod from-alien-form (form (type (eql 'referenced)) &rest args)
-  (declare (ignore type))
-  (destructuring-bind (type) args
-    (if (subtypep type 'gobject)
-	(let ((instance (make-symbol "INSTANCE")))
-	  `(let ((,instance ,(from-alien-form form type)))
-	     (when ,instance
-	       (%object-unref (proxy-location ,instance)))
-	     ,instance))
-      (error "~A is not a subclass of GOBJECT" type))))
-
-(export 'referenced)
+(deftype referenced (type) type)
+
+(define-type-method from-alien-form ((type referenced) form &key (ref :free))
+  (cond
+   ((not (eq ref :free))
+    (error "Keyword arg :REF to FROM-ALIEN-FORM should be :FREE for type ~A. It was give ~A" type ref))
+   ((subtypep type 'gobject)
+    (from-alien-form (second (type-expand-to 'referenced type)) form :ref ref))))
+
+(define-type-method from-alien-function ((type referenced) &key (ref :free))
+  (cond
+   ((not (eq ref :free))
+    (error "Keyword arg :REF to FROM-ALIEN-FUNCTION should be :FREE for type ~A. It was give ~A" type ref))
+;   ((subtypep type 'gobject) (call-next-method type ref :free))))
+   ((subtypep type 'gobject) 
+    (from-alien-function (second (type-expand-to 'referenced type)) :ref ref))))