C callbacks cleaned up and ported to new API

[clg] / glib / gobject.lisp

diff --git a/glib/gobject.lisp b/glib/gobject.lisp
index e5562380cece9dadc70e050e681093058d527f9f..aa951f863832ca5170f418f931dba602287c936a 100644 (file)
--- a/glib/gobject.lisp
+++ b/glib/gobject.lisp
@@ -1,55 +1,355 @@
-;; Common Lisp bindings for GTK+ v2.0
-;; Copyright (C) 2000-2001 Espen S. Johnsen <esj@stud.cs.uit.no>
+;; Common Lisp bindings for GTK+ v2.x
+;; Copyright 2000-2005 Espen S. Johnsen <espen@users.sf.net>

 ;;
 ;;

-;; This library is free software; you can redistribute it and/or
-;; modify it under the terms of the GNU Lesser General Public
-;; License as published by the Free Software Foundation; either
-;; version 2 of the License, or (at your option) any later version.
+;; Permission is hereby granted, free of charge, to any person obtaining
+;; a copy of this software and associated documentation files (the
+;; "Software"), to deal in the Software without restriction, including
+;; without limitation the rights to use, copy, modify, merge, publish,
+;; distribute, sublicense, and/or sell copies of the Software, and to
+;; permit persons to whom the Software is furnished to do so, subject to
+;; the following conditions:

 ;;
 ;;

-;; This library is distributed in the hope that it will be useful,
-;; but WITHOUT ANY WARRANTY; without even the implied warranty of
-;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-;; Lesser General Public License for more details.
+;; The above copyright notice and this permission notice shall be
+;; included in all copies or substantial portions of the Software.

 ;;
 ;;

-;; You should have received a copy of the GNU Lesser General Public
-;; License along with this library; if not, write to the Free Software
-;; Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+;; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+;; EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+;; MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+;; IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+;; CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+;; 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 1.12 2002-04-02 14:57:19 espen Exp $
+;; $Id: gobject.lisp,v 1.48 2006-02-19 19:31:14 espen Exp $

 
 (in-package "GLIB")
 
 
 
 (in-package "GLIB")
 
 

+;;;; Metaclass used for subclasses of gobject
+

 (eval-when (:compile-toplevel :load-toplevel :execute)
 (eval-when (:compile-toplevel :load-toplevel :execute)

-  (defclass gobject (ginstance)
-    ()
-    (:metaclass ginstance-class)
-    (:alien-name "GObject")
-    (:copy %object-ref)
-    (:free %object-unref)))
+;;   (push :debug-ref-counting *features*)
+  (defclass gobject-class (ginstance-class)
+    ((instance-slots-p :initform nil
+      :documentation "Non NIL if the class has slots with instance allocation")))

 
 

-(defmethod initialize-instance ((object gobject) &rest initargs)
-  (declare (ignore initargs))
-  (setf  (slot-value object 'location) (%gobject-new (type-number-of object)))
-  (call-next-method))
+  (defmethod validate-superclass ((class gobject-class) (super standard-class))
+;  (subtypep (class-name super) 'gobject)
+    t))

 
 

-(defbinding (%gobject-new "g_object_new") () pointer
-  (type type-number)
-  (nil null))
+(defclass direct-property-slot-definition (direct-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-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-only :initarg :construct-only :reader construct-only-property-p)))
+
+(defclass direct-user-data-slot-definition (direct-virtual-slot-definition)
+  ())

 
 

+(defclass effective-user-data-slot-definition (effective-virtual-slot-definition)
+  ())

 
 

-(defbinding %object-ref (type location) pointer
+
+(defbinding %object-ref () pointer

   (location pointer))
 
   (location pointer))
 

-(defbinding %object-unref (type location) nil
+(defbinding %object-unref () nil

   (location pointer))
 
   (location pointer))
 

+#+glib2.8
+(progn
+  (define-callback toggle-ref-callback nil
+      ((data pointer) (location pointer) (last-ref-p boolean))
+    #+debug-ref-counting
+    (if last-ref-p
+       (format t "Object at 0x~8,'0X has no foreign references~%" (sap-int location))
+      (format t "Foreign reference added to object at 0x~8,'0X~%" (sap-int 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
+    (location pointer)
+    (toggle-ref-callback callback)
+    (nil null))
+
+  (defbinding %object-remove-toggle-ref () pointer
+    (location 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
+  (define-callback weak-ref-callback nil ((data pointer) (location pointer))
+    (format t "Object at 0x~8,'0X being finalized~%" (sap-int location)))
+  
+  (defbinding %object-weak-ref () pointer
+    (location pointer)
+    (weak-ref-callback callback)
+    (nil null)))
+
+
+; (defbinding object-class-install-param () nil
+;   (class pointer)
+;   (id unsigned-int)
+;   (parameter parameter))
+
+; (defbinding object-class-find-param-spec () parameter
+;   (class pointer)
+;   (name string))
+
+(defun signal-name-to-string (name)
+  (substitute #\_ #\- (string-downcase (string name))))
+
+
+(defmethod direct-slot-definition-class ((class gobject-class) &rest initargs)
+  (case (getf initargs :allocation)
+    (:property (find-class 'direct-property-slot-definition))
+    (:user-data (find-class 'direct-user-data-slot-definition))
+    (t (call-next-method))))
+
+(defmethod effective-slot-definition-class ((class gobject-class) &rest initargs)
+  (case (getf initargs :allocation)
+    (:property (find-class 'effective-property-slot-definition))
+    (:user-data (find-class 'effective-user-data-slot-definition))
+    (t (call-next-method))))
+
+(defmethod compute-effective-slot-definition-initargs ((class gobject-class) direct-slotds)
+  (if (eq (slot-definition-allocation (first direct-slotds)) :property)
+      (nconc 
+       (list :pname (signal-name-to-string 
+                    (most-specific-slot-value direct-slotds 'pname
+                     (slot-definition-name (first direct-slotds))))
+            :readable (most-specific-slot-value direct-slotds 'readable t)
+            :writable (most-specific-slot-value direct-slotds 'writable t)
+            :construct-only (most-specific-slot-value direct-slotds 
+                              'construct-only nil))
+       (call-next-method))
+    (call-next-method)))
+
+
+(defvar *ignore-setting-construct-only-property* nil)
+(declaim (special *ignore-setting-construct-only-property*))
+
+(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 (not (slot-boundp slotd 'setter))
+      (cond
+       ((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)))))
+
+       ((construct-only-property-p slotd)
+       (setf 
+        (slot-value slotd 'setter)
+        #'(lambda (value object)
+            (declare (ignore value object))
+            (unless *ignore-setting-construct-only-property*
+              (error "Slot is not writable: ~A" (slot-definition-name slotd)))))))))
+
+  (call-next-method))
+
+(defmethod initialize-internal-slot-functions ((slotd effective-user-data-slot-definition))
+  (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)))
+
+
+
+;;;; 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)" (sap-int (foreign-location instance)) (ref-count instance))
+      (write-string "at \"unbound\"" stream))))
+
+
+(defun initial-add (object function initargs key pkey)
+  (loop 
+   as (initarg value . rest) = initargs then rest
+   do (cond
+       ((eq initarg key) (funcall function object value))
+       ((eq initarg pkey) (mapc #'(lambda (value)
+                                   (funcall function object value))
+                               value)))
+       while rest))
+
+(defun initial-apply-add (object function initargs key pkey)
+  (initial-add object #'(lambda (object value)
+                         (apply function object (mklist value)))
+              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 "An object of class ~A has instance slots and should only be created with MAKE-INSTANCE" class)
+    (call-next-method)))
+
+
+(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 ((element-size (+ +gvalue-size+ +size-of-pointer+))
+           (num-slots (length init-slots)))
+       (with-allocated-memory (params (* num-slots element-size))
+          (loop
+          with string-writer = (writer-function 'string)
+          for (slotd . value) in init-slots
+          as offset = params then (sap+ offset element-size)
+          as type = (slot-definition-type slotd)
+          as pname = (slot-definition-pname slotd)
+          do (funcall string-writer pname offset)
+              (gvalue-init (sap+ offset +size-of-pointer+) type value))
+
+         (unwind-protect
+             (%gobject-newv (type-number-of object) num-slots params)
+       
+           (loop
+            with string-destroy = (destroy-function 'string)
+            repeat num-slots
+            as offset = params then (sap+ offset element-size)
+            do (funcall string-destroy offset)
+               (gvalue-unset (sap+ offset +size-of-pointer+)))))))
+
+     (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))
+  (prog1
+      (call-next-method)
+    #+debug-ref-counting(%object-weak-ref (foreign-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 instance-finalizer ((instance gobject))
+  (let ((location (foreign-location instance)))
+    #+glib2.8
+    (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)
+           (%object-remove-toggle-ref location))
+      #'(lambda ()
+         #+debug-ref-counting
+         (format t "Finalizing proxy for 0x~8,'0X~%" (sap-int location))
+         (remove-cached-instance location)
+         (%object-unref location)))
+    #-glib2.8
+    #'(lambda ()
+       (remove-cached-instance location)
+         (%object-unref location))))
+

 
 

-(defun object-ref (object)
-  (%object-ref nil (proxy-location object)))
+(defbinding (%gobject-new "g_object_new") () pointer
+  (type type-number)
+  (nil null))

 
 

-(defun object-unref (object)
-  (%object-unref nil (proxy-location object)))
+(defbinding (%gobject-newv "g_object_newv") () pointer
+  (type type-number)
+  (n-parameters unsigned-int)
+  (params pointer))

 
 
 
 
 
 


@@ -75,107 +375,49 @@ (defbinding object-freeze-notify () nil
 (defbinding object-thaw-notify () nil
   (object gobject))
 
 (defbinding object-thaw-notify () nil
   (object gobject))
 

+
+;;;; User data
+

 (defbinding %object-set-qdata-full () nil
   (object gobject)
   (id quark)
   (data unsigned-long)
 (defbinding %object-set-qdata-full () nil
   (object gobject)
   (id quark)
   (data unsigned-long)

-  (destroy-marshal pointer))
+  (destroy-marshal callback))

 
 

+(define-callback user-data-destroy-callback nil ((id unsigned-int))
+  (destroy-user-data id))

 
 

-;;;; User data
+(defun (setf user-data) (data object key)
+  (%object-set-qdata-full object (quark-intern key)
+   (register-user-data data) user-data-destroy-callback)
+  data)

 
 

+;; deprecated

 (defun (setf object-data) (data object key &key (test #'eq))
 (defun (setf object-data) (data object key &key (test #'eq))

-  (%object-set-qdata-full
-   object (quark-from-object key :test test)
-   (register-user-data data) *destroy-notify*)
-  data)
+  (assert (eq test #'eq))
+  (setf (user-data object key) data))

 
 (defbinding %object-get-qdata () unsigned-long
   (object gobject)              
   (id quark))
 
 
 (defbinding %object-get-qdata () unsigned-long
   (object gobject)              
   (id quark))
 

-(defun object-data (object key &key (test #'eq))
-  (find-user-data
-   (%object-get-qdata object (quark-from-object key :test test))))
-
-
-
-;;;; Metaclass used for subclasses of gobject
-
-(eval-when (:compile-toplevel :load-toplevel :execute)
-  (defclass gobject-class (ginstance-class))
-
-  (defclass direct-gobject-slot-definition (direct-virtual-slot-definition)
-    ((pname :reader slot-definition-pname)))
-
-  (defclass effective-gobject-slot-definition
-    (effective-virtual-slot-definition)))
-
-  
-
-; (defbinding object-class-install-param () nil
-;   (class pointer)
-;   (id unsigned-int)
-;   (parameter parameter))
-
-; (defbinding object-class-find-param-spec () parameter
-;   (class pointer)
-;   (name string))
-
-(defun signal-name-to-string (name)
-  (substitute #\_ #\- (string-downcase (string name))))
-
-(defmethod initialize-instance :after ((slotd direct-gobject-slot-definition)
-                                      &rest initargs &key pname)
-  (declare (ignore initargs))
-  (when pname
-    (setf
-     (slot-value slotd 'pname)
-     (signal-name-to-string (slot-definition-name slotd)))))
+(defun user-data (object key)
+  (find-user-data (%object-get-qdata object (quark-intern key))))

 
 

-(defmethod direct-slot-definition-class ((class gobject-class) initargs)
-  (case (getf initargs :allocation)
-    (:property (find-class 'direct-gobject-slot-definition))
-    (t (call-next-method))))
+;; deprecated
+(defun object-data (object key &key (test #'eq))
+  (assert (eq test #'eq))
+  (user-data object key))

 
 

-(defmethod effective-slot-definition-class ((class gobject-class) initargs)
-  (case (getf initargs :allocation)
-    (:property (find-class 'effective-gobject-slot-definition))
-    (t (call-next-method))))
+(defun user-data-p (object key)
+  (user-data-exists-p (%object-get-qdata object (quark-intern key))))

 
 

-(defmethod compute-virtual-slot-accessors
-    ((class gobject-class) (slotd effective-gobject-slot-definition)
-     direct-slotds)
-  (with-slots (type) slotd
-    (let ((pname (slot-definition-pname (first direct-slotds)))
-         (type-number (find-type-number type)))
-      (list
-       #'(lambda (object)
-          (with-gc-disabled
-            (let ((gvalue (gvalue-new type-number)))
-              (%object-get-property object pname gvalue)
-              (unwind-protect
-                  (funcall
-                   (intern-reader-function (type-from-number type-number)) gvalue +gvalue-value-offset+) ; temporary workaround for wrong topological sorting of types
-                (gvalue-free gvalue t)))))
-       #'(lambda (value object)
-          (with-gc-disabled
-            (let ((gvalue (gvalue-new type-number)))
-              (funcall
-               (intern-writer-function (type-from-number type-number)) ; temporary
-               value gvalue +gvalue-value-offset+)
-              (%object-set-property object pname gvalue)
-              (funcall
-               (intern-destroy-function (type-from-number type-number)) ; temporary
-               gvalue +gvalue-value-offset+)
-              (gvalue-free gvalue nil)
-              value)))))))
-
-(defmethod validate-superclass ((class gobject-class)
-                               (super pcl::standard-class))
-;  (subtypep (class-name super) 'gobject)
-  t)
+(defbinding %object-steal-qdata () unsigned-long
+  (object gobject)              
+  (id quark))

 
 

+(defun unset-user-data (object key)
+  (destroy-user-data (%object-steal-qdata object (quark-intern key))))

 
 
 ;;;;
 
 
 ;;;;


@@ -184,21 +426,30 @@ (defbinding %object-class-list-properties () pointer
   (class pointer)
   (n-properties unsigned-int :out))
 
   (class pointer)
   (n-properties unsigned-int :out))
 

-(defun query-object-class-properties (type-number &optional
-                                     inherited-properties)
-  (let ((class (type-class-ref type-number)))
-    (multiple-value-bind (array length)
-       (%object-class-list-properties class)
-      (unwind-protect
-         (let ((all-properties
-                (map-c-array 'list #'identity array 'param length)))
-           (if (not inherited-properties)
-               (delete-if
-                #'(lambda (param)
-                    (not (eql type-number (param-owner-type param))))
-                all-properties)
-             all-properties))
-       (deallocate-memory array)))))
+
+(defun %map-params (params length type inherited-p)
+  (if inherited-p
+      (map-c-vector 'list #'identity params 'param length)
+    (let ((properties ()))
+      (map-c-vector 'list 
+       #'(lambda (param)
+          (when (eql (param-owner-type param) type)
+            (push param properties)))
+       params 'param length)
+      (nreverse properties))))
+
+(defun query-object-class-properties (type &optional inherited-p)
+  (let* ((type-number (find-type-number type t))
+        (class (type-class-ref type-number)))
+    (unwind-protect
+        (multiple-value-bind (array length)
+            (%object-class-list-properties class)
+          (unless (null-pointer-p array)
+            (unwind-protect
+                (%map-params array length type-number inherited-p)
+              (deallocate-memory array))))
+;      (type-class-unref type-number)
+      )))

 
 
 (defun default-slot-name (name)
 
 
 (defun default-slot-name (name)


@@ -208,65 +459,114 @@ (defun default-slot-accessor (class-name slot-name type)
   (intern
    (format
     nil "~A-~A~A" class-name slot-name
   (intern
    (format
     nil "~A-~A~A" class-name slot-name

-    (if (eq 'boolean type) "-P" ""))))
-
-(defun expand-gobject-type (type-number &optional options
-                           (metaclass 'gobject-class))
-  (let* ((supers (cons (supertype type-number) (implements type-number)))
-        (class  (type-from-number type-number))
-        (override-slots (getf options :slots))
-        (expanded-slots
-         (mapcar
-          #'(lambda (param)
-              (with-slots (name flags value-type documentation) param
-                (let* ((slot-name (default-slot-name name))
-                       (slot-type value-type) ;(type-from-number value-type t))
-                       (accessor
-                        (default-slot-accessor class slot-name (type-from-number slot-type)))) ; temporary workaround for wrong topological sorting of types
-                  `(,slot-name
-                    :allocation :property
-                    :pname ,name
-                    ,@(cond
-                       ((and
-                         (member :writable flags)
-                         (member :readable flags))
-                        (list :accessor accessor))
-                       ((member :writable flags)
-                        (list :writer `(setf ,accessor)))
-                       ((member :readable flags)
-                        (list :reader accessor)))
-                    ,@(when (or
-                             (member :construct flags)
-                             (member :writable flags))
-                        (list :initarg (intern (string slot-name) "KEYWORD")))
-                    :type ,slot-type
-                    ,@(when documentation
-                        (list :documentation documentation))))))
-          (query-object-class-properties type-number))))
-
-    (dolist (slot-def override-slots)
-      (let ((name (car slot-def))
-           (pname (getf (cdr slot-def) :pname)))
-       (setq
-        expanded-slots
-        (delete-if
-         #'(lambda (expanded-slot-def)
-             (or
-              (eq name (car expanded-slot-def))
-              (and
-               pname
-               (string= pname (getf (cdr expanded-slot-def) :pname)))))
-         expanded-slots))
-
-       (unless (getf (cdr slot-def) :ignore)
-         (push slot-def expanded-slots))))
-    
-    `(progn
-       (defclass ,class ,supers
-        ,expanded-slots
+    (if (eq type 'boolean) "-P" ""))))
+
+
+(defun slot-definition-from-property (class property &optional slot-name args)
+  (with-slots (name flags value-type documentation) property
+    (let* ((slot-name (or slot-name (default-slot-name name)))
+          (slot-type (or (getf args :type) (type-from-number value-type) 'pointer))
+          (accessor (default-slot-accessor class slot-name slot-type)))
+      
+      `(,slot-name
+       :allocation :property :pname ,name
+
+       ,@(when (find :unbound args) (list :unbound (getf args :unbound)))
+       ,@(when (find :getter args) (list :getter (getf args :getter)))
+       ,@(when (find :setter args) (list :setter (getf args :setter)))
+       
+       ;; accessors
+       ,@(cond
+          ((and
+            (member :writable flags) (member :readable flags)
+            (not (member :construct-only flags)))
+           (list :accessor accessor))
+          ((and (member :writable flags) (not (member :construct-only flags)))
+           (list :writer `(setf ,accessor)))
+          ((member :readable flags)
+           (list :reader accessor)))
+
+       ;; readable/writable/construct
+       ,@(when (or (not (member :writable flags))
+                   (member :construct-only flags))
+           '(:writable nil))
+       ,@(when (not (member :readable flags))
+           '(:readable nil))
+       ,@(when (member :construct-only flags)
+           '(:construct-only t))
+       
+       ;; initargs
+       ,@(if (find :initarg args)
+             (let ((initarg (getf args :initarg)))
+               (etypecase initarg
+                 (null ())
+                 (symbol `(:initarg ,initarg))))
+           (when (or (member :construct flags)
+                     (member :construct-only flags)
+                     (member :writable flags))
+             (list :initarg (intern (string slot-name) "KEYWORD"))))
+       
+       :type ,slot-type
+       :documentation ,documentation))))
+
+
+(defun slot-definitions (class properties slots)
+  (loop 
+   for property in properties
+   as slot = (or
+             (find (param-name property) slots 
+              :key #'(lambda (slot) (getf (rest slot) :pname)) 
+              :test #'string=)
+             (find (param-name property) slots 
+              :key #'first :test #'string-equal))
+   do (cond
+       ((not slot) 
+       (push (slot-definition-from-property class property) slots))
+       ((getf (rest slot) :merge)
+       (setf 
+        (rest slot) 
+        (rest (slot-definition-from-property class property (first slot) (rest slot)))))))
+  (delete-if #'(lambda (slot) (getf (rest slot) :ignore)) 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)))    
+    `(defclass ,class ,supers
+        ,(unless forward-p
+           (slot-definitions class (query-object-class-properties type) slots))

         (:metaclass ,metaclass)
         (:metaclass ,metaclass)

-        (:alien-name ,(find-type-name type-number))))))
+        (:gtype ,(register-type-as type)))))
+
+(defun gobject-dependencies (type)
+  (delete-duplicates 
+   (cons
+    (supertype type)
+    (append 
+     (type-interfaces type)
+     (mapcar #'param-value-type (query-object-class-properties type))))))
+
+
+(register-derivable-type 'gobject "GObject" 'expand-gobject-type 'gobject-dependencies)
+
+
+;;; 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))

 
 

-(register-derivable-type 'gobject "GObject" 'expand-gobject-type)
+(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 (foreign-location ,instance)))
+            ,instance))
+      (error "~A is not a subclass of GOBJECT" type))))

 
 

+(export 'referenced)