X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~mdw/git/clg/blobdiff_plain/88f2b61bbb65eb24f55a9e3e55532f1379b00875..a7d19b2a6d3e11b28842476b80ef68d81fb6b8ac:/glib/proxy.lisp

diff --git a/glib/proxy.lisp b/glib/proxy.lisp
index 4176447..1ca8fe5 100644
--- a/glib/proxy.lisp
+++ b/glib/proxy.lisp
@@ -1,387 +1,688 @@
-;; Common Lisp bindings for GTK+ v2.0
-;; Copyright (C) 2000 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: proxy.lisp,v 1.6 2001-10-21 16:55:39 espen Exp $
+;; $Id: proxy.lisp,v 1.36 2006-02-26 15:30:01 espen Exp $
 
 (in-package "GLIB")
 
-
 ;;;; Superclass for all metaclasses implementing some sort of virtual slots
 
 (eval-when (:compile-toplevel :load-toplevel :execute)
-  (defclass virtual-slot-class (pcl::standard-class))
+  (defclass virtual-slots-class (standard-class) 
+    ())
 
   (defclass direct-virtual-slot-definition (standard-direct-slot-definition)
     ((setter :reader slot-definition-setter :initarg :setter)
-     (getter :reader slot-definition-getter :initarg :getter)))
+     (getter :reader slot-definition-getter :initarg :getter)
+     (unbound :reader slot-definition-unbound :initarg :unbound)
+     (boundp :reader slot-definition-boundp :initarg :boundp)))
   
-  (defclass effective-virtual-slot-definition
-    (standard-effective-slot-definition)))
+  (defclass effective-virtual-slot-definition (standard-effective-slot-definition)
+    ((setter :reader slot-definition-setter :initarg :setter)
+     (getter :reader slot-definition-getter :initarg :getter)
+     (unbound :reader slot-definition-unbound :initarg :unbound)
+     (boundp :reader slot-definition-boundp :initarg :boundp)))
+
+  (defclass direct-special-slot-definition (standard-direct-slot-definition)
+    ((special :initarg :special :accessor slot-definition-special)))
   
+  (defclass effective-special-slot-definition (standard-effective-slot-definition)
+    ((special :initarg :special :accessor slot-definition-special))))
+
+(defvar *unbound-marker* (gensym "UNBOUND-MARKER-"))
+
+(defun most-specific-slot-value (instances slot &optional (default *unbound-marker*))
+  (let ((object (find-if
+		 #'(lambda (ob)
+		     (and (slot-exists-p ob slot) (slot-boundp ob slot)))
+		 instances)))
+    (if object
+	(slot-value object slot)
+      default)))
 
-(defmethod direct-slot-definition-class ((class virtual-slot-class) initargs)
-  (if (eq (getf initargs :allocation) :virtual)
-      (find-class 'direct-virtual-slot-definition)
-    (call-next-method)))
 
-(defmethod effective-slot-definition-class ((class virtual-slot-class) initargs)
-  (if (eq (getf initargs :allocation) :virtual)
-      (find-class 'effective-virtual-slot-definition)
-    (call-next-method)))
+(defmethod direct-slot-definition-class ((class virtual-slots-class) &rest initargs)
+  (cond
+   ((eq (getf initargs :allocation) :virtual)
+    (find-class 'direct-virtual-slot-definition))
+   ((getf initargs :special)
+    (find-class 'direct-special-slot-definition))
+   (t (call-next-method))))
+
+(defmethod effective-slot-definition-class ((class virtual-slots-class) &rest initargs)
+  (cond
+   ((eq (getf initargs :allocation) :virtual)
+    (find-class 'effective-virtual-slot-definition))
+   ((getf initargs :special)
+    (find-class 'effective-special-slot-definition))
+   (t (call-next-method))))
+
+
+(defmethod initialize-internal-slot-functions ((slotd effective-virtual-slot-definition))
+  (if (not (slot-boundp slotd 'getter))
+      (setf
+       (slot-value slotd 'reader-function)
+       #'(lambda (object)
+	   (declare (ignore object))
+	   (error "Slot is not readable: ~A" (slot-definition-name slotd)))
+       (slot-value slotd 'boundp-function)
+       #'(lambda (object) (declare (ignore object)) nil))
+
+    (let ((getter-function
+	   (let ((getter (slot-value slotd 'getter)))
+	     (etypecase getter
+	       (function getter)
+	       (symbol 
+		#'(lambda (object)
+		    (funcall getter object)))
+	       (string 
+		(let ((reader nil))
+		  (setf (slot-value slotd 'reader-function)
+			#'(lambda (object)
+			    (unless reader
+			      (setq reader
+			       (mkbinding getter 
+				(slot-definition-type slotd) 'pointer)))
+			    (funcall reader (foreign-location object))))))))))
+
+      (setf 
+       (slot-value slotd 'boundp-function)
+       (cond
+	((slot-boundp slotd 'unbound)
+	 (let ((unbound-value (slot-value slotd 'unbound)))
+	   #'(lambda (object)
+	       (not (eq (funcall getter-function object) unbound-value)))))
+	((slot-boundp slotd 'boundp)
+	 (let ((boundp (slot-value slotd 'boundp)))
+	   (etypecase boundp
+	     (function boundp)
+	     (symbol #'(lambda (object)
+			 (funcall boundp object)))
+	     (string (let ((reader ()))
+		       #'(lambda (object)
+			   (unless reader
+			     (setq reader
+			      (mkbinding boundp
+			       (slot-definition-type slotd) 'pointer)))
+			   (funcall reader (foreign-location object))))))))
+	((let ((unbound-value-method
+		(find-applicable-type-method 'unbound-value 
+		 (slot-definition-type slotd) nil)))
+	   (when unbound-value-method
+	     (let ((unbound-value 
+		    (funcall unbound-value-method (slot-definition-type slotd))))
+	       #'(lambda (object)
+		   (not (eq (funcall getter-function object) unbound-value)))))))
+	(#'(lambda (object) (declare (ignore object)) t))))
 
-(defun %most-specific-slot-value (slotds slot &optional default)
-  (let ((slotd
-	 (find-if
-	  #'(lambda (slotd)
-	      (and
-	       (slot-exists-p slotd slot)
-	       (slot-boundp slotd slot)))
-	  slotds)))
-    (if slotd
-	(slot-value slotd slot)
-      default)))
- 
-(defgeneric compute-virtual-slot-accessors (class slotd direct-slotds))
-
-(defmethod compute-virtual-slot-accessors
-    ((class virtual-slot-class)
-     (slotd effective-virtual-slot-definition)
-     direct-slotds)
-    (let ((getter (%most-specific-slot-value direct-slotds 'getter))
-	  (setter (%most-specific-slot-value direct-slotds 'setter)))
-      (list getter setter)))
-
-(defmethod compute-effective-slot-definition
-    ((class virtual-slot-class) direct-slotds)
-  (let ((slotd (call-next-method)))
-    (when (typep slotd 'effective-virtual-slot-definition)
       (setf
-       (slot-value slotd 'pcl::location)
-       (compute-virtual-slot-accessors class slotd direct-slotds)))
-    slotd))
+       (slot-value slotd 'reader-function)
+       (cond
+	((slot-boundp slotd 'unbound)
+	 (let ((unbound (slot-value slotd 'unbound))
+	       (slot-name (slot-definition-name slotd)))
+	   #'(lambda (object)
+	       (let ((value (funcall getter-function object)))
+		 (if (eq value unbound)
+		     (slot-unbound (class-of object) object slot-name)
+		   value)))))
+	((slot-boundp slotd 'boundp)
+	 (let ((boundp-function (slot-value slotd 'boundp-function)))
+	   #'(lambda (object)
+	       (and
+		(funcall boundp-function object)
+		(funcall getter-function object)))))
+	((let ((unbound-value-method
+		(find-applicable-type-method 'unbound-value 
+		 (slot-definition-type slotd) nil)))
+	   (when unbound-value-method
+	     (let ((unbound-value 
+		    (funcall unbound-value-method (slot-definition-type slotd)))
+		   (slot-name (slot-definition-name slotd)))
+	       #'(lambda (object)
+		   (let ((value (funcall getter-function object)))
+		     (if (eq value unbound-value)
+			 (slot-unbound (class-of object) object slot-name)
+			 value)))))))
+	(getter-function)))))
+
+  (setf 
+   (slot-value slotd 'writer-function)
+   (if (not (slot-boundp slotd 'setter))
+       #'(lambda (value object)
+	   (declare (ignore value object))
+	   (error "Slot is not writable: ~A" (slot-definition-name slotd)))
+     (with-slots (setter) slotd
+       (etypecase setter
+	 (function setter)
+	 ((or symbol cons) 
+	  #'(lambda (value object)
+	      (funcall (fdefinition setter) value object)))
+	 (string
+	  (let ((writer ()))
+	    (setf
+	     (slot-value slotd 'writer-function)
+	     #'(lambda (value object)
+		 (unless writer
+		   (setq writer
+		    (mkbinding setter 'nil 'pointer 
+		     (slot-definition-type slotd))))
+		 (funcall writer (foreign-location object) value)))))))))
+
+  #-sbcl>=0.9.8(initialize-internal-slot-gfs (slot-definition-name slotd)))
+
+
+
+(defmethod compute-slot-accessor-info ((slotd effective-virtual-slot-definition) type gf)
+  nil)
+
+(defmethod compute-effective-slot-definition-initargs ((class virtual-slots-class) direct-slotds)
+  (typecase (first direct-slotds)
+    (direct-virtual-slot-definition
+     (let ((initargs ()))
+       (let ((getter (most-specific-slot-value direct-slotds 'getter)))
+	 (unless (eq getter *unbound-marker*)
+	   (setf (getf initargs :getter) getter)))
+       (let ((setter (most-specific-slot-value direct-slotds 'setter)))
+	 (unless (eq setter *unbound-marker*)
+	   (setf (getf initargs :setter) setter)))
+       (let ((unbound (most-specific-slot-value direct-slotds 'unbound)))
+	 (unless (eq unbound *unbound-marker*)
+	   (setf (getf initargs :unbound) unbound)))
+       (let ((boundp (most-specific-slot-value direct-slotds 'boundp)))
+	 (unless (eq boundp *unbound-marker*)
+	   (setf (getf initargs :boundp) boundp)))
+       ;; Need this to prevent type expansion in SBCL >= 0.9.8
+       (let ((type (most-specific-slot-value direct-slotds 'type)))
+	 (unless (eq type *unbound-marker*)
+	   (setf (getf initargs :type) type)))
+       (nconc initargs (call-next-method))))
+    (direct-special-slot-definition
+     (append '(:special t) (call-next-method)))
+    (t (call-next-method))))
+
 
 (defmethod slot-value-using-class
-    ((class virtual-slot-class) (object standard-object)
+    ((class virtual-slots-class) (object standard-object)
      (slotd effective-virtual-slot-definition))
-  (let ((reader (first (slot-definition-location slotd))))
-    (if reader
-	(funcall reader object)
-      (slot-unbound class object (slot-definition-name slotd)))))
+  (if (funcall (slot-value slotd 'boundp-function) object)
+      (funcall (slot-value slotd 'reader-function) object)
+    (slot-unbound class object (slot-definition-name slotd))))
 
 (defmethod slot-boundp-using-class
-    ((class virtual-slot-class) (object standard-object)
+    ((class virtual-slots-class) (object standard-object)
      (slotd effective-virtual-slot-definition))
-   (and (first (slot-definition-location slotd)) t))
-    
-(defmethod (setf slot-value-using-class)
-    (value (class virtual-slot-class) (object standard-object)
+  (funcall (slot-value slotd 'boundp-function) object))
+  
+(defmethod (setf slot-value-using-class) 
+    (value (class virtual-slots-class) (object standard-object)
      (slotd effective-virtual-slot-definition))
-  (let ((setter (second (slot-definition-location slotd))))
-    (cond
-     ((null setter)
-      (error
-       "Can't set read-only slot ~A in ~A"
-       (slot-definition-name slotd)
-       object))
-     ((or (functionp setter) (symbolp setter))
-      (funcall setter value object)
-      value)
-     (t
-      (funcall (fdefinition setter) value object)
-      value))))
-	
+  (funcall (slot-value slotd 'writer-function) value object))
+
+  
 (defmethod validate-superclass
-    ((class virtual-slot-class) (super pcl::standard-class))
+    ((class virtual-slots-class) (super standard-class))
   t)
 
 
+(defmethod slot-definition-special ((slotd standard-direct-slot-definition))
+  (declare (ignore slotd))
+  nil)
+
+(defmethod slot-definition-special ((slotd standard-effective-slot-definition))
+  (declare (ignore slotd))
+  nil)
+
+
 ;;;; Proxy cache
 
-(internal *instance-cache*)
 (defvar *instance-cache* (make-hash-table :test #'eql))
 
-(defun cache-instance (instance)
+(defun cache-instance (instance &optional (weak-ref t))
   (setf
-   (gethash (system:sap-int (proxy-location instance)) *instance-cache*)
-   (ext:make-weak-pointer instance)))
+   (gethash (sap-int (foreign-location instance)) *instance-cache*)
+   (if weak-ref
+       (make-weak-pointer instance)
+     instance)))
 
 (defun find-cached-instance (location)
-  (let ((ref (gethash (system:sap-int location) *instance-cache*)))
+  (let ((ref (gethash (sap-int location) *instance-cache*)))
     (when ref
-      (ext:weak-pointer-value ref))))
+      (if (weak-pointer-p ref)
+	  (weak-pointer-value ref)
+	ref))))
+
+(defun instance-cached-p (location)
+  (gethash (sap-int location) *instance-cache*))
 
 (defun remove-cached-instance (location)
-  (remhash (system:sap-int location) *instance-cache*))
+  (remhash (sap-int location) *instance-cache*))
+
+;; For debuging
+(defun list-cached-instances ()
+  (let ((instances ()))
+    (maphash #'(lambda (location ref)
+		 (declare (ignore location))
+		 (push ref instances))
+	     *instance-cache*)
+    instances))
+			
+;; Instances that gets invalidated tend to be short lived, but created
+;; in large numbers. So we're keeping them in a hash table to be able
+;; to reuse them (and thus reduce consing)
+(defvar *invalidated-instance-cache* (make-hash-table :test #'eql))
+
+(defun cache-invalidated-instance (instance)
+  (push instance
+   (gethash (class-of instance) *invalidated-instance-cache*)))
+
+(defun find-invalidated-instance (class)
+  (when (gethash class *invalidated-instance-cache*)
+    (pop (gethash class *invalidated-instance-cache*))))
+
+(defun list-invalidated-instances ()
+  (let ((instances ()))
+    (maphash #'(lambda (location ref)
+		 (declare (ignore location))
+		 (push ref instances))
+	     *invalidated-instance-cache*)
+    instances))
 
 
 
 ;;;; Proxy for alien instances
 
-(eval-when (:compile-toplevel :load-toplevel :execute)
-  (defclass proxy ()
-    ((location :reader proxy-location :type system-area-pointer)))
+;; TODO: add a ref-counted-proxy subclass
+(defclass proxy ()
+  ((location :special t :type pointer))
+  (:metaclass virtual-slots-class))
 
-  (defgeneric initialize-proxy (object &rest initargs))
-  (defgeneric instance-finalizer (object)))
+(defgeneric instance-finalizer (object))
+(defgeneric reference-foreign (class location))
+(defgeneric unreference-foreign (class location))
+(defgeneric invalidate-instance (object))
+(defgeneric allocate-foreign (object &key &allow-other-keys))
 
+(defun foreign-location (instance)
+  (slot-value instance 'location))
 
-(defmethod initialize-instance :after ((instance proxy)
-				       &rest initargs &key)
-  (declare (ignore initargs))
-  (cache-instance instance)
-  (ext:finalize instance (instance-finalizer instance)))
-
-(defmethod initialize-proxy ((instance proxy)
-			     &rest initargs &key location weak-ref)
-  (declare (ignore initargs))
-  (setf 
-   (slot-value instance 'location)
-   (if weak-ref
-       (funcall
-	(proxy-class-copy (class-of instance))
-	(type-of instance) location)
-     location))
-  (cache-instance instance)
-  (ext:finalize instance (instance-finalizer instance)))
+(defun (setf foreign-location) (location instance)
+  (setf (slot-value instance 'location) location))
 
-(defmethod instance-finalizer ((instance proxy))
-  (let ((free (proxy-class-free (class-of instance)))
-	(type (type-of instance))
-	(location (proxy-location instance)))
-    (declare
-     (type symbol type)
-     (type system-area-pointer location))
-    #'(lambda ()
-	(funcall free type location)
-	(remove-cached-instance location))))
+(defun proxy-valid-p (instance)
+  (slot-boundp instance 'location))
 
+(defmethod reference-foreign ((name symbol) location)
+  (reference-foreign (find-class name) location))
 
-(deftype-method translate-type-spec proxy (type-spec)
-  (declare (ignore type-spec))
-  (translate-type-spec 'pointer))
+(defmethod unreference-foreign ((name symbol) location)
+  (unreference-foreign (find-class name) location))
 
-(deftype-method size-of proxy (type-spec)
-  (declare (ignore type-spec))
-  (size-of 'pointer))
+(defmethod unreference-foreign :around ((class class) location)
+  (unless (null-pointer-p location)
+    (call-next-method)))
 
-(deftype-method translate-from-alien
-    proxy (type-spec location &optional weak-ref)
-  `(let ((location ,location))
-     (unless (null-pointer-p location)
-       (ensure-proxy-instance ',type-spec location ,weak-ref))))
+(defmethod print-object ((instance proxy) stream)
+  (print-unreadable-object (instance stream :type t :identity nil)
+    (if (slot-boundp instance 'location)
+	(format stream "at 0x~X" (sap-int (foreign-location instance)))
+      (write-string "at <unbound>" stream))))
+
+(defmethod initialize-instance :around ((instance proxy) &rest initargs &key &allow-other-keys) 
+  (setf  
+   (foreign-location instance)
+   (apply #'allocate-foreign instance initargs))
+  (prog1
+      (call-next-method)
+    (cache-instance instance)
+    (finalize instance (instance-finalizer instance))))
 
-(deftype-method translate-to-alien
-    proxy (type-spec instance &optional weak-ref)
-  (if weak-ref
-      `(proxy-location ,instance)
-    `(funcall
-      ',(proxy-class-copy (find-class type-spec))
-      ',type-spec (proxy-location ,instance))))
+(defmethod instance-finalizer ((instance proxy))
+  (let ((location (foreign-location instance))
+	(class (class-of instance)))    
+;;     (unless (find-method #'unreference-foreign nil (list (class-of class) t) nil)
+;;       (error "No matching method for UNREFERENCE-INSTANCE when called with class ~A" class))
+    #'(lambda ()
+	(remove-cached-instance location)
+	(unreference-foreign class location))))
 
-(deftype-method unreference-alien proxy (type-spec location)
-  `(funcall ',(proxy-class-free (find-class type-spec)) ',type-spec ,location))
+;; Any reference to the foreign object the instance may have held
+;; should be released before this method is invoked
+(defmethod invalidate-instance ((instance proxy))
+  (remove-cached-instance (foreign-location instance))
+  (slot-makunbound instance 'location)
+  (cancel-finalization instance)
+  (cache-invalidated-instance instance))
 
-(defun proxy-instance-size (proxy)
-  (proxy-class-size (class-of proxy)))
 
 ;;;; Metaclass used for subclasses of proxy
 
+(defgeneric most-specific-proxy-superclass (class))
+(defgeneric direct-proxy-superclass (class))
+  
+
 (eval-when (:compile-toplevel :load-toplevel :execute)
-  (defclass proxy-class (virtual-slot-class)
-    ((size :reader proxy-class-size)
-     (copy :reader proxy-class-copy)
-     (free :reader proxy-class-free)))
+  (defclass proxy-class (virtual-slots-class)
+    ((size :reader foreign-size)))
 
   (defclass direct-alien-slot-definition (direct-virtual-slot-definition)
-    ((allocation :initform :alien)
-     (offset :reader slot-definition-offset :initarg :offset)))
+    ((offset :reader slot-definition-offset :initarg :offset))
+    (:default-initargs :allocation :alien))
   
   (defclass effective-alien-slot-definition (effective-virtual-slot-definition)
-    ((offset :reader slot-definition-offset)))
-  
-  (defclass effective-virtual-alien-slot-definition
-    (effective-virtual-slot-definition))
-
+    ((offset :reader slot-definition-offset :initarg :offset)))
 
   (defmethod most-specific-proxy-superclass ((class proxy-class))
     (find-if
      #'(lambda (class)
 	 (subtypep (class-name class) 'proxy))
-     (cdr (pcl::compute-class-precedence-list class))))
+     (cdr (compute-class-precedence-list class))))
 
   (defmethod direct-proxy-superclass ((class proxy-class))
     (find-if
      #'(lambda (class)
 	 (subtypep (class-name class) 'proxy))
-     (pcl::class-direct-superclasses class)))
-
-  (defmethod shared-initialize ((class proxy-class) names
-				&rest initargs &key size copy free)
-    (declare (ignore initargs))
+     (class-direct-superclasses class)))
+  
+  (defmethod shared-initialize ((class proxy-class) names &key size)
     (call-next-method)
     (cond
-     (size (setf (slot-value class 'size) (first size)))
-     ((slot-boundp class 'size) (slot-makunbound class 'size)))
-    (cond
-     (copy (setf (slot-value class 'copy) (first copy)))
-     ((slot-boundp class 'copy) (slot-makunbound class 'copy)))
-    (cond
-     (free (setf (slot-value class 'free) (first free)))
-     ((slot-boundp class 'free) (slot-makunbound class 'free))))
+      (size (setf (slot-value class 'size) (first size)))
+      ((slot-boundp class 'size) (slot-makunbound class 'size))))
 
-  (defmethod finalize-inheritance ((class proxy-class))
-    (call-next-method)
-    (let ((super (most-specific-proxy-superclass class)))
-      (unless (or (not super) (eq super (find-class 'proxy)))
- 	(unless (or (slot-boundp class 'copy) (not (slot-boundp super 'copy)))
- 	  (setf (slot-value class 'copy) (proxy-class-copy super)))
- 	(unless (or (slot-boundp class 'free) (not (slot-boundp super 'free)))
- 	  (setf (slot-value class 'free) (proxy-class-free super))))))
-
-  (defmethod direct-slot-definition-class ((class proxy-class) initargs)
+  (defmethod direct-slot-definition-class ((class proxy-class) &rest initargs)
     (case (getf initargs :allocation)
-      ((nil :alien) (find-class 'direct-alien-slot-definition))
-;      (:instance (error "Allocation :instance not allowed in class ~A" class))
+      (:alien (find-class 'direct-alien-slot-definition))
       (t (call-next-method))))
-
-  (defmethod effective-slot-definition-class ((class proxy-class) initargs)
+  
+  (defmethod effective-slot-definition-class ((class proxy-class) &rest initargs)
     (case (getf initargs :allocation)
       (:alien (find-class 'effective-alien-slot-definition))
-      (:virtual (find-class 'effective-virtual-alien-slot-definition))
       (t (call-next-method))))
   
-  (defmethod compute-virtual-slot-accessors
-      ((class proxy-class) (slotd effective-alien-slot-definition)
-       direct-slotds)
-    (with-slots (offset type) slotd
-      (let ((reader (intern-reader-function type))
-	    (writer (intern-writer-function type))
-	    (destroy (intern-destroy-function type)))
-	(setf offset (slot-definition-offset (first direct-slotds)))
-	(list
-	 #'(lambda (object)
-	     (funcall reader (proxy-location object) offset))
-	 #'(lambda (value object)
-	     (let ((location (proxy-location object)))
-	       (funcall destroy location offset)
-	       (funcall writer value location offset)))))))
- 
-  (defmethod compute-virtual-slot-accessors
-      ((class proxy-class)
-       (slotd effective-virtual-alien-slot-definition)
-       direct-slotds)
-    (destructuring-bind (getter setter) (call-next-method)
-      (let ((class-name (class-name class)))
-	(with-slots (type) slotd
-	  (list
-	   (if (stringp getter)
-	       (let ((getter (mkbinding-late getter type 'pointer)))
-		 #'(lambda (object)
-		     (funcall getter (proxy-location object))))
-	     getter)
-	   (if (stringp setter)
-	       (let ((setter (mkbinding-late setter 'nil 'pointer type)))
-		 #'(lambda (value object)
-		     (funcall setter (proxy-location object) value)))
-	     setter))))))
+  
+  (defmethod compute-effective-slot-definition-initargs ((class proxy-class) direct-slotds)
+    (if (eq (slot-definition-allocation (first direct-slotds)) :alien)
+	(nconc 
+	 (list :offset (most-specific-slot-value direct-slotds 'offset))
+	 (call-next-method))
+      (call-next-method)))
+  
+
+  (defmethod initialize-internal-slot-functions ((slotd effective-alien-slot-definition))
+    (with-slots (offset) slotd
+      (let ((type (slot-definition-type slotd)))
+	(unless (slot-boundp slotd 'getter)
+	  (let ((reader (reader-function type)))
+	    (setf 
+	     (slot-value slotd 'getter)
+	     #'(lambda (object)
+		 (funcall reader (foreign-location object) offset)))))
+
+	(unless (slot-boundp slotd 'setter)
+	  (let ((writer (writer-function type))
+		(destroy (destroy-function type)))
+	    (setf 
+	     (slot-value slotd 'setter)
+	     #'(lambda (value object)
+		 (let ((location (foreign-location object)))
+		   (funcall destroy location offset) ; destroy old value
+		   (funcall writer value location offset))))))))
+
+    (call-next-method))
+  
+  ;; TODO: call some C code to detect this a compile time
+  (defconstant +struct-alignmen+ 4)
+
+  (defun align-offset (size)
+    (if (zerop (mod size +struct-alignmen+))
+	size
+      (+ size (- +struct-alignmen+ (mod size +struct-alignmen+)))))
 
   (defmethod compute-slots ((class proxy-class))
-    (with-slots (direct-slots size) class
-      (let ((current-offset
-	     (proxy-class-size (most-specific-proxy-superclass class)))
-	    (max-size 0))
-	(dolist (slotd direct-slots)
-	  (when (eq (slot-definition-allocation slotd) :alien)
-	    (with-slots (offset type) slotd
-	      (unless (slot-boundp slotd 'offset)
-		(setf offset current-offset))
-	      (setq current-offset (+ offset (size-of type)))
-	      (setq max-size (max max-size current-offset)))))
-	(unless (slot-boundp class 'size)
-	  (setf size max-size))))
+    (let ((alien-slots 
+	   (remove-if-not
+	    #'(lambda (slotd)
+		(eq (slot-definition-allocation slotd) :alien))
+	    (class-direct-slots class))))      
+      (when alien-slots
+	(loop 
+	 as offset = (align-offset (foreign-size 
+				    (most-specific-proxy-superclass class)))
+	             then (align-offset 
+			   (+ 
+			    (slot-definition-offset slotd)
+			    (size-of (slot-definition-type slotd))))
+       for slotd in alien-slots
+       unless (slot-boundp slotd 'offset)
+       do (setf (slot-value slotd 'offset) offset))))
     (call-next-method))
-   
-  (defmethod validate-superclass ((class proxy-class)
-				  (super pcl::standard-class))
+
+  (defmethod validate-superclass ((class proxy-class) (super standard-class))
     (subtypep (class-name super) 'proxy))
+  
+  (defmethod foreign-size ((class-name symbol))
+    (foreign-size (find-class class-name))))
 
-  (defmethod proxy-class-size (class)
-    (declare (ignore class))
-    0)
+(defmethod foreign-size ((object proxy))
+  (foreign-size (class-of object)))
+  
 
-  (defgeneric make-proxy-instance (class location weak-ref
-				   &rest initargs &key)))
+(define-type-method alien-type ((class proxy))
+  (declare (ignore class))
+  (alien-type 'pointer))
 
-(defmethod make-proxy-instance ((class symbol) location weak-ref
-				&rest initargs &key)
-  (apply #'make-proxy-instance (find-class class) location weak-ref initargs))
+(define-type-method size-of ((class proxy))
+  (declare (ignore class))
+  (size-of 'pointer))
 
-(defmethod make-proxy-instance ((class proxy-class) location weak-ref
-				&rest initargs &key)
-  (let ((instance (allocate-instance class)))
-    (apply
-     #'initialize-proxy
-     instance :location location :weak-ref weak-ref initargs)
-    instance))
+(define-type-method from-alien-form ((type proxy) location)
+  (let ((class (type-expand type)))
+    `(ensure-proxy-instance ',class ,location)))
+
+(define-type-method from-alien-function ((type proxy))
+  (let ((class (type-expand type)))
+    #'(lambda (location)
+	(ensure-proxy-instance class location))))
 
-(defun ensure-proxy-instance (class location weak-ref &rest initargs)
-  (or
-   (find-cached-instance location)
-   (apply #'make-proxy-instance class location weak-ref initargs)))
+(define-type-method to-alien-form ((type proxy) instance)
+  (declare (ignore type))
+  `(foreign-location ,instance))
+
+(define-type-method to-alien-function ((type proxy))
+  (declare (ignore type))
+  #'foreign-location)
+
+(define-type-method copy-from-alien-form ((type proxy) location)
+  (let ((class (type-expand type)))
+    `(ensure-proxy-instance ',class (reference-foreign ',class ,location))))
+
+(define-type-method copy-from-alien-function ((type proxy))
+  (let ((class (type-expand type)))
+    #'(lambda (location)
+	(ensure-proxy-instance class (reference-foreign class location)))))
+
+(define-type-method copy-to-alien-form ((type proxy) instance)
+  (let ((class (type-expand type)))
+    `(reference-foreign ',class (foreign-location ,instance))))
+
+(define-type-method copy-to-alien-function ((type proxy))
+  (let ((class (type-expand type)))
+    #'(lambda (instance)
+	(reference-foreign class (foreign-location instance)))))
+
+(define-type-method writer-function ((type proxy))
+  (let ((class (type-expand type)))
+    #'(lambda (instance location &optional (offset 0))
+	(assert (null-pointer-p (sap-ref-sap location offset)))
+	(setf 
+	 (sap-ref-sap location offset)
+	 (reference-foreign class (foreign-location instance))))))
+
+(define-type-method reader-function ((type proxy))
+  (let ((class (type-expand type)))
+    #'(lambda (location &optional (offset 0) weak-p)
+	(declare (ignore weak-p))
+	(let ((instance (sap-ref-sap location offset)))
+	  (unless (null-pointer-p instance)
+	    (ensure-proxy-instance class (reference-foreign class instance)))))))
+
+(define-type-method destroy-function ((type proxy))
+  (let ((class (type-expand type)))
+    #'(lambda (location &optional (offset 0))
+	(unreference-foreign class (sap-ref-sap location offset)))))
+
+(define-type-method unbound-value ((type proxy))
+  (declare (ignore type))
+  nil)
 
+(defun ensure-proxy-instance (class location &rest initargs)
+  "Returns a proxy object representing the foreign object at the give
+location. If an existing object is not found in the cache
+MAKE-PROXY-INSTANCE is called to create one."
+  (unless (null-pointer-p location)
+    (or 
+     #-debug-ref-counting(find-cached-instance location)
+     #+debug-ref-counting
+     (let ((instance (find-cached-instance location)))
+       (when instance
+	 (format t "Object found in cache: ~A~%" instance)
+	 instance))
+     (let ((instance (apply #'make-proxy-instance class location initargs)))
+       (cache-instance instance)
+       instance))))
+
+(defgeneric make-proxy-instance (class location &key weak)
+  (:documentation "Creates a new proxy object representing the foreign
+object at the give location. If WEAK is non NIL the foreign memory
+will not be released when the proxy is garbage collected."))
+
+(defmethod make-proxy-instance ((class symbol) location &rest initargs)
+  (apply #'make-proxy-instance (find-class class) location initargs))
+
+(defmethod make-proxy-instance ((class proxy-class) location &key weak)
+  (let ((instance
+	 (or
+	  (find-invalidated-instance class)
+	  (allocate-instance class))))
+    (setf (foreign-location instance) location)
+    (unless weak
+      (finalize instance (instance-finalizer instance)))
+    instance))
 
 
 ;;;; Superclasses for wrapping of C structures
 
-(eval-when (:compile-toplevel :load-toplevel :execute)
-  (defclass struct (proxy)
-    ()
-    (:metaclass proxy-class)
-    (:copy %copy-struct)
-    (:free %free-struct)))
-
-(defmethod initialize-instance ((structure struct)
-				&rest initargs)
+(defclass struct (proxy)
+  ()
+  (:metaclass proxy-class)
+  (:size 0))
+
+(defmethod allocate-foreign ((struct struct) &rest initargs)
   (declare (ignore initargs))
-  (setf 
-   (slot-value structure 'location)
-   (allocate-memory (proxy-class-size (class-of structure))))
-  (call-next-method))
+  (let ((size (foreign-size (class-of struct))))
+    (if (zerop size)
+	(error "~A has zero size" (class-of struct))
+      (allocate-memory size))))
 
 
-(defun %copy-struct (type location)
-  (copy-memory location (proxy-class-size (find-class type))))
+;;;; Metaclasses used for subclasses of struct
 
-(defun %free-struct (type location)
-  (declare (ignore type))
-  (deallocate-memory location))
+(eval-when (:compile-toplevel :load-toplevel :execute)
+  (defclass struct-class (proxy-class)
+    ()))
+
+(defmethod direct-slot-definition-class ((class struct-class) &rest initargs)
+  (if (not (getf initargs :allocation))
+      (find-class 'direct-alien-slot-definition)
+    (call-next-method)))
 
+(defmethod reference-foreign ((class struct-class) location)
+  (copy-memory location (foreign-size class)))
 
-;(eval-when (:compile-toplevel :load-toplevel :execute)
-  (defclass static (struct)
-    ()
-    (:metaclass proxy-class)
-    (:copy %copy-static)
-    (:free %free-static));)
+(defmethod unreference-foreign ((class struct-class) location)
+  (deallocate-memory location))
 
-(defun %copy-static (type location)
+(defmethod compute-slots :around ((class struct-class))
+    (let ((slots (call-next-method)))
+      (when (and 
+	     #-sbcl>=0.9.8(class-finalized-p class)
+	     (not (slot-boundp class 'size)))
+        (let ((size (loop
+		     for slotd in slots
+		     when (eq (slot-definition-allocation slotd) :alien)
+		     maximize (+ 
+			       (slot-definition-offset slotd)
+			       (size-of (slot-definition-type slotd))))))
+	  (setf (slot-value class 'size) (+ size (mod size +struct-alignmen+)))))
+      slots))
+
+(define-type-method callback-from-alien-form ((type struct) form)
+  (let ((class (type-expand type)))
+    `(ensure-proxy-instance ',class ,form :weak t)))
+
+(define-type-method callback-cleanup-form ((type struct) form)
   (declare (ignore type))
+  `(invalidate-instance ,form))
+
+(define-type-method reader-function ((type struct))
+  (let ((class (type-expand type)))
+    #'(lambda (location &optional (offset 0) weak-p)
+	(let ((instance (sap-ref-sap location offset)))
+	  (unless (null-pointer-p instance)
+	    (if weak-p
+		(ensure-proxy-instance class instance :weak t)
+	      (ensure-proxy-instance class (reference-foreign class instance))))))))
+
+
+(defclass static-struct-class (struct-class)
+  ())
+
+(defmethod reference-foreign ((class static-struct-class) location)
+  (declare (ignore class))
   location)
 
-(defun %free-static (type location)
-  (declare (ignore type location))
+(defmethod unreference-foreign ((class static-struct-class) location)
+  (declare (ignore class location))
   nil)
+
+;;; Pseudo type for structs which are inlined in other objects
+
+(deftype inlined (type) type)
+
+(define-type-method size-of ((type inlined))
+  (let ((class (type-expand (second type))))
+    (foreign-size class)))
+
+(define-type-method reader-function ((type inlined))
+  (let ((class (type-expand (second type))))
+    #'(lambda (location &optional (offset 0) weak-p)
+	(declare (ignore weak-p))
+	(ensure-proxy-instance class 
+	 (reference-foreign class (sap+ location offset))))))
+
+(define-type-method writer-function ((type inlined))
+  (let ((class (type-expand (second type))))
+    #'(lambda (instance location &optional (offset 0))
+	(copy-memory (foreign-location instance) (foreign-size class) (sap+ location offset)))))
+
+(export 'inlined)