[clg] / glib / proxy.lisp

;; Common Lisp bindings for GTK+ v2.0
;; Copyright (C) 2000 Espen S. Johnsen <esj@stud.cs.uit.no>
;;
;; 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.
;;
;; 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.
;;
;; 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

;; $Id: proxy.lisp,v 1.19 2005-02-03 23:09:04 espen Exp $

(in-package "GLIB")

;;;; Superclass for all metaclasses implementing some sort of virtual slots

(eval-when (:compile-toplevel :load-toplevel :execute)
  (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)
     (unbound :reader slot-definition-unbound :initarg :unbound)
     (boundp :reader slot-definition-boundp :initarg :boundp)))
  
  (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))))
  
  (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-slots-class) &rest initargs)
  (if (eq (getf initargs :allocation) :virtual)
      (find-class 'direct-virtual-slot-definition)
    (call-next-method)))

(defmethod effective-slot-definition-class ((class virtual-slots-class) &rest initargs)
  (if (eq (getf initargs :allocation) :virtual)
      (find-class 'effective-virtual-slot-definition)
    (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 "Can't read slot: ~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 (proxy-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 (proxy-location object))))))))
	((multiple-value-bind (unbound-p unbound-value)
	     (unbound-value (slot-definition-type slotd))
	   (when unbound-p
	     #'(lambda (object)
		 (not (eq (funcall getter-function object) unbound-value))))))
	(#'(lambda (object) (declare (ignore object)) t))))

      (setf
       (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)))))
	((multiple-value-bind (unbound-p unbound-value)
	     (unbound-value (slot-definition-type slotd))
	   (let ((slot-name (slot-definition-name slotd)))
	     (when unbound-p
	       #'(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 (object)
	   (declare (ignore object))
	   (error "Can't set slot: ~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 (proxy-location object) value)))))))))

  (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)
  (if (typep (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)))
	(nconc initargs (call-next-method)))
    (call-next-method)))


(defmethod slot-value-using-class
    ((class virtual-slots-class) (object standard-object)
     (slotd effective-virtual-slot-definition))
  (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-slots-class) (object standard-object)
     (slotd effective-virtual-slot-definition))
  (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))
  (funcall (slot-value slotd 'writer-function) value object))

  
(defmethod validate-superclass
    ((class virtual-slots-class) (super standard-class))
  t)


;;;; Proxy cache

(internal *instance-cache*)
(defvar *instance-cache* (make-hash-table :test #'eql))

(defun cache-instance (instance)
  (setf
   (gethash (sap-int (proxy-location instance)) *instance-cache*)
   (make-weak-pointer instance)))

(defun find-cached-instance (location)
  (let ((ref (gethash (sap-int location) *instance-cache*)))
    (when ref
      (weak-pointer-value ref))))

(defun instance-cached-p (location)
  (gethash (sap-int location) *instance-cache*))

(defun remove-cached-instance (location)
  (remhash (sap-int location) *instance-cache*))

;; For debuging
(defun cached-instances ()
  (let ((instances ()))
    (maphash #'(lambda (location ref)
		 (declare (ignore location))
		 (push (weak-pointer-value ref) instances))
	     *instance-cache*)
    instances))
			

;;;; Proxy for alien instances

(defclass proxy ()
  ((location :reader proxy-location :type system-area-pointer)))

(defgeneric initialize-proxy (object &rest initargs))
(defgeneric instance-finalizer (object))
(defgeneric reference-foreign (class location))
(defgeneric unreference-foreign (class location))

(defmethod reference-foreign ((name symbol) location)
  (reference-foreign (find-class name) location))

(defmethod unreference-foreign ((name symbol) location)
  (unreference-foreign (find-class name) location))

(defmethod unreference-foreign :around ((class class) location)
  (unless (null-pointer-p location)
;;     (format t "Unreferencing ~A at ~A" (class-name class) location)
;;     (finish-output *standard-output*)
    (call-next-method)
;;     (write-line " done")
;;     (finish-output *standard-output*)
    ))

(defmethod print-object ((instance proxy) stream)
  (print-unreadable-object (instance stream :type t :identity nil)
    (when (slot-boundp instance 'location)
      (format stream "at 0x~X" (sap-int (proxy-location instance))))))

(defmethod initialize-instance :around ((instance proxy) &key location)
  (if location
      (setf (slot-value instance 'location) location)      
    (call-next-method))
  (cache-instance instance)
  (finalize instance (instance-finalizer instance))
  instance)

(defmethod instance-finalizer ((instance proxy))
  (let ((location (proxy-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))))


;;;; 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-slots-class)
    ((size :reader proxy-instance-size)))

  (defclass direct-alien-slot-definition (direct-virtual-slot-definition)
    ((allocation :initform :alien)
     (offset :reader slot-definition-offset :initarg :offset)))
  
  (defclass effective-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 (compute-class-precedence-list class))))

  (defmethod direct-proxy-superclass ((class proxy-class))
    (find-if
     #'(lambda (class)
	 (subtypep (class-name class) 'proxy))
     (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))))
  
  (defmethod direct-slot-definition-class ((class proxy-class) &rest initargs)
    (case (getf initargs :allocation)
      ((nil :alien) (find-class 'direct-alien-slot-definition))
      (t (call-next-method))))
  
  (defmethod effective-slot-definition-class ((class proxy-class) &rest initargs)
    (case (getf initargs :allocation)
      (:alien (find-class 'effective-alien-slot-definition))
      (t (call-next-method))))
  
  
  (defmethod compute-effective-slot-definition-initargs ((class proxy-class) direct-slotds)
    (if (eq (most-specific-slot-value direct-slotds 'allocation) :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 (proxy-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 (proxy-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)

  (defmethod compute-slots ((class proxy-class))
    (loop 
     with offset = (let ((size-of-super-classes
			  (proxy-instance-size 
			   (most-specific-proxy-superclass class))))
		     (+ size-of-super-classes 
			(mod size-of-super-classes +struct-alignmen+)))
     with size = offset
     for slotd in (class-direct-slots class)
     when (eq (slot-definition-allocation slotd) :alien)
     do (if (not (slot-boundp slotd 'offset))
	    (setf (slot-value slotd 'offset) offset)
	  (setq offset (slot-value slotd 'offset)))

        (incf offset (size-of (slot-definition-type slotd)))
	(incf offset (mod offset +struct-alignmen+))
	(setq size (max size offset))

     finally (unless (slot-boundp class 'size)
	       (setf (slot-value class 'size) size)))
    (call-next-method))

  
  (defmethod validate-superclass ((class proxy-class) (super standard-class))
    (subtypep (class-name super) 'proxy))
  
  (defmethod proxy-instance-size (class)
    (declare (ignore class))
    0)

  (defmethod proxy-instance-size ((class-name symbol))
    (proxy-instance-size (find-class class-name)))
)
  
(defmethod alien-type ((class proxy-class) &rest args)
  (declare (ignore class args))
  (alien-type 'pointer))

(defmethod size-of ((class proxy-class) &rest args)
  (declare (ignore class args))
  (size-of 'pointer))

(defmethod from-alien-form (location (class proxy-class) &rest args)
  (declare (ignore args))
  `(ensure-proxy-instance ',(class-name class) ,location))

(defmethod from-alien-function ((class proxy-class) &rest args)
  (declare (ignore args))  
  #'(lambda (location)
      (ensure-proxy-instance class location)))

(defmethod to-alien-form (instance (class proxy-class) &rest args)
  (declare (ignore class args))
  `(proxy-location ,instance))

(defmethod to-alien-function ((class proxy-class) &rest args)
  (declare (ignore class args))
  #'proxy-location)

(defmethod copy-from-alien-form (location (class proxy-class) &rest args)
  (declare (ignore args))
  (let ((class-name (class-name class)))
    `(ensure-proxy-instance ',class-name
      (reference-foreign ',class-name ,location))))

(defmethod copy-from-alien-function ((class proxy-class) &rest args)
  (declare (ignore args))  
  #'(lambda (location)
      (ensure-proxy-instance class (reference-foreign class location))))

(defmethod copy-to-alien-form (instance (class proxy-class) &rest args)
  (declare (ignore args))
  `(reference-foreign ',(class-name class) (proxy-location ,instance)))

(defmethod copy-to-alien-function ((class proxy-class) &rest args)
  (declare (ignore args))
  #'(lambda (instance)
      (reference-foreign class (proxy-location instance))))

(defmethod writer-function ((class proxy-class) &rest args)
  (declare (ignore args))
  #'(lambda (instance location &optional (offset 0))
      (assert (null-pointer-p (sap-ref-sap location offset)))
      (setf 
       (sap-ref-sap location offset)
       (reference-foreign class (proxy-location instance)))))

(defmethod reader-function ((class proxy-class) &rest args)
  (declare (ignore args))
  #'(lambda (location &optional (offset 0))
      (let ((instance (sap-ref-sap location offset)))
	(unless (null-pointer-p instance)
	  (ensure-proxy-instance class (reference-foreign class instance))))))

(defmethod destroy-function ((class proxy-class) &rest args)
  (declare (ignore args))
  #'(lambda (location &optional (offset 0))
      (unreference-foreign class (sap-ref-sap location offset))))

(defmethod unbound-value ((class proxy-class) &rest args)
  (declare (ignore args))
  (values t nil))

(defgeneric ensure-proxy-instance (class location)
  (:documentation "Returns a proxy object representing the foreign object at the give location."))

(defmethod ensure-proxy-instance :around (class location)
  (unless (null-pointer-p location)
    (or 
     (find-cached-instance location)
     (call-next-method))))
  
(defmethod ensure-proxy-instance ((class symbol) location)
  (ensure-proxy-instance (find-class class) location))

(defmethod ensure-proxy-instance ((class proxy-class) location)
  (make-instance class :location location))


;;;; Superclasses for wrapping of C structures

(defclass struct (proxy)
  ()
  (:metaclass proxy-class))

(defmethod initialize-instance ((struct struct) &rest initargs)
  (declare (ignore initargs))
  (unless (slot-boundp struct 'location)
    (let ((size (proxy-instance-size (class-of struct))))
      (if (zerop size)
	  (error "~A has zero size" (class-of struct))
	(setf (slot-value struct 'location) (allocate-memory size)))))
  (call-next-method))


;;;; Metaclasses used for subclasses of struct

(defclass struct-class (proxy-class)
  ())

(defmethod reference-foreign ((class struct-class) location)
  (copy-memory location (proxy-instance-size class)))

(defmethod unreference-foreign ((class struct-class) location)
  (deallocate-memory location))


(defclass static-struct-class (struct-class)
  ())

(defmethod reference-foreign ((class static-struct-class) location)
  (declare (ignore class))
  location)

(defmethod unreference-foreign ((class static-struct-class) location)
  (declare (ignore class location))
  nil)
Commit	Line	Data
94f15c3c	1	;; Common Lisp bindings for GTK+ v2.0
	2	;; Copyright (C) 2000 Espen S. Johnsen <esj@stud.cs.uit.no>
	3	;;
	4	;; This library is free software; you can redistribute it and/or
	5	;; modify it under the terms of the GNU Lesser General Public
	6	;; License as published by the Free Software Foundation; either
	7	;; version 2 of the License, or (at your option) any later version.
	8	;;
	9	;; This library is distributed in the hope that it will be useful,
	10	;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	12	;; Lesser General Public License for more details.
	13	;;
	14	;; You should have received a copy of the GNU Lesser General Public
	15	;; License along with this library; if not, write to the Free Software
	16	;; Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	17
73572c12	18	;; $Id: proxy.lisp,v 1.19 2005-02-03 23:09:04 espen Exp $
94f15c3c	19
	20	(in-package "GLIB")
	21
94f15c3c	22	;;;; Superclass for all metaclasses implementing some sort of virtual slots
	23
	24	(eval-when (:compile-toplevel :load-toplevel :execute)
9adccb27	25	(defclass virtual-slots-class (standard-class)
4d83a8a6	26	())
94f15c3c	27
94f15c3c	28	(defclass direct-virtual-slot-definition (standard-direct-slot-definition)
12d0437e	29	((setter :reader slot-definition-setter :initarg :setter)
4d83a8a6	30	(getter :reader slot-definition-getter :initarg :getter)
eeda1c2d	31	(unbound :reader slot-definition-unbound :initarg :unbound)
4d83a8a6	32	(boundp :reader slot-definition-boundp :initarg :boundp)))
94f15c3c	33
4d83a8a6	34	(defclass effective-virtual-slot-definition (standard-effective-slot-definition)
	35	((setter :reader slot-definition-setter :initarg :setter)
	36	(getter :reader slot-definition-getter :initarg :getter)
eeda1c2d	37	(unbound :reader slot-definition-unbound :initarg :unbound)
73572c12	38	(boundp :reader slot-definition-boundp :initarg :boundp))))
eeda1c2d	39
eeda1c2d	40	(defvar unbound-marker (gensym "UNBOUND-MARKER-"))
4d83a8a6	41
eeda1c2d	42	(defun most-specific-slot-value (instances slot &optional
eeda1c2d	43	(default unbound-marker))
4d83a8a6	44	(let ((object (find-if
	45	#'(lambda (ob)
	46	(and (slot-exists-p ob slot) (slot-boundp ob slot)))
	47	instances)))
	48	(if object
	49	(slot-value object slot)
73572c12	50	default)));)
4d83a8a6	51
94f15c3c	52
94f15c3c	53
9adccb27	54	(defmethod direct-slot-definition-class ((class virtual-slots-class) &rest initargs)
94f15c3c	55	(if (eq (getf initargs :allocation) :virtual)
	56	(find-class 'direct-virtual-slot-definition)
	57	(call-next-method)))
	58
9adccb27	59	(defmethod effective-slot-definition-class ((class virtual-slots-class) &rest initargs)
94f15c3c	60	(if (eq (getf initargs :allocation) :virtual)
	61	(find-class 'effective-virtual-slot-definition)
	62	(call-next-method)))
	63
4d83a8a6	64
4d83a8a6	65	(defmethod initialize-internal-slot-functions ((slotd effective-virtual-slot-definition))
eeda1c2d	66	(if (not (slot-boundp slotd 'getter))
eeda1c2d	67	(setf
4d83a8a6	68	(slot-value slotd 'reader-function)
eeda1c2d	69	#'(lambda (object)
	70	(declare (ignore object))
	71	(error "Can't read slot: ~A" (slot-definition-name slotd)))
	72	(slot-value slotd 'boundp-function)
	73	#'(lambda (object) (declare (ignore object)) nil))
	74
	75	(let ((getter-function
	76	(let ((getter (slot-value slotd 'getter)))
	77	(etypecase getter
	78	(function getter)
	79	(symbol
	80	#'(lambda (object)
	81	(funcall getter object)))
	82	(string
	83	(let ((reader nil))
	84	(setf (slot-value slotd 'reader-function)
	85	#'(lambda (object)
	86	(unless reader
12b7df04	87	(setq reader
	88	(mkbinding getter
	89	(slot-definition-type slotd) 'pointer)))
eeda1c2d	90	(funcall reader (proxy-location object))))))))))
eeda1c2d	91
4d83a8a6	92	(setf
eeda1c2d	93	(slot-value slotd 'boundp-function)
eeda1c2d	94	(cond
eeda1c2d	95	((slot-boundp slotd 'unbound)
eeda1c2d	96	(let ((unbound-value (slot-value slotd 'unbound)))
12b7df04	97	#'(lambda (object)
	98	(not (eq (funcall getter-function object) unbound-value)))))
	99	((slot-boundp slotd 'boundp)
	100	(let ((boundp (slot-value slotd 'boundp)))
eeda1c2d	101	(etypecase boundp
	102	(function boundp)
	103	(symbol #'(lambda (object)
	104	(funcall boundp object)))
	105	(string (let ((reader ()))
	106	#'(lambda (object)
	107	(unless reader
	108	(setq reader
	109	(mkbinding boundp
	110	(slot-definition-type slotd) 'pointer)))
12b7df04	111	(funcall reader (proxy-location object))))))))
	112	((multiple-value-bind (unbound-p unbound-value)
	113	(unbound-value (slot-definition-type slotd))
	114	(when unbound-p
	115	#'(lambda (object)
	116	(not (eq (funcall getter-function object) unbound-value))))))
	117	(#'(lambda (object) (declare (ignore object)) t))))
eeda1c2d	118
	119	(setf
	120	(slot-value slotd 'reader-function)
	121	(cond
	122	((slot-boundp slotd 'unbound)
	123	(let ((unbound (slot-value slotd 'unbound))
	124	(slot-name (slot-definition-name slotd)))
12b7df04	125	#'(lambda (object)
	126	(let ((value (funcall getter-function object)))
	127	(if (eq value unbound)
	128	(slot-unbound (class-of object) object slot-name)
	129	value)))))
eeda1c2d	130	((slot-boundp slotd 'boundp)
eeda1c2d	131	(let ((boundp-function (slot-value slotd 'boundp-function)))
12b7df04	132	#'(lambda (object)
	133	(and
	134	(funcall boundp-function object)
	135	(funcall getter-function object)))))
	136	((multiple-value-bind (unbound-p unbound-value)
	137	(unbound-value (slot-definition-type slotd))
	138	(let ((slot-name (slot-definition-name slotd)))
	139	(when unbound-p
	140	#'(lambda (object)
	141	(let ((value (funcall getter-function object)))
	142	(if (eq value unbound-value)
	143	(slot-unbound (class-of object) object slot-name)
	144	value)))))))
eeda1c2d	145	(getter-function)))))
	146
	147	(setf
	148	(slot-value slotd 'writer-function)
	149	(if (not (slot-boundp slotd 'setter))
	150	#'(lambda (object)
	151	(declare (ignore object))
	152	(error "Can't set slot: ~A" (slot-definition-name slotd)))
	153	(with-slots (setter) slotd
4d83a8a6	154	(etypecase setter
4d83a8a6	155	(function setter)
eeda1c2d	156	((or symbol cons)
	157	#'(lambda (value object)
	158	(funcall (fdefinition setter) value object)))
7d1ddc9e	159	(string
eeda1c2d	160	(let ((writer ()))
	161	(setf
	162	(slot-value slotd 'writer-function)
	163	#'(lambda (value object)
	164	(unless writer
	165	(setq writer
	166	(mkbinding setter 'nil 'pointer
	167	(slot-definition-type slotd))))
	168	(funcall writer (proxy-location object) value)))))))))
	169
4d83a8a6	170	(initialize-internal-slot-gfs (slot-definition-name slotd)))
	171
	172
	173
eeda1c2d	174	(defmethod compute-slot-accessor-info ((slotd effective-virtual-slot-definition) type gf)
4d83a8a6	175	nil)
4d83a8a6	176
9adccb27	177	(defmethod compute-effective-slot-definition-initargs ((class virtual-slots-class) direct-slotds)
eeda1c2d	178	(if (typep (first direct-slotds) 'direct-virtual-slot-definition)
	179	(let ((initargs ()))
	180	(let ((getter (most-specific-slot-value direct-slotds 'getter)))
	181	(unless (eq getter unbound-marker)
	182	(setf (getf initargs :getter) getter)))
	183	(let ((setter (most-specific-slot-value direct-slotds 'setter)))
	184	(unless (eq setter unbound-marker)
	185	(setf (getf initargs :setter) setter)))
	186	(let ((unbound (most-specific-slot-value direct-slotds 'unbound)))
	187	(unless (eq unbound unbound-marker)
	188	(setf (getf initargs :unbound) unbound)))
	189	(let ((boundp (most-specific-slot-value direct-slotds 'boundp)))
	190	(unless (eq boundp unbound-marker)
	191	(setf (getf initargs :boundp) boundp)))
	192	(nconc initargs (call-next-method)))
4d83a8a6	193	(call-next-method)))
4d83a8a6	194
94f15c3c	195
94f15c3c	196	(defmethod slot-value-using-class
9adccb27	197	((class virtual-slots-class) (object standard-object)
94f15c3c	198	(slotd effective-virtual-slot-definition))
4d83a8a6	199	(if (funcall (slot-value slotd 'boundp-function) object)
	200	(funcall (slot-value slotd 'reader-function) object)
	201	(slot-unbound class object (slot-definition-name slotd))))
94f15c3c	202
94f15c3c	203	(defmethod slot-boundp-using-class
9adccb27	204	((class virtual-slots-class) (object standard-object)
94f15c3c	205	(slotd effective-virtual-slot-definition))
4d83a8a6	206	(funcall (slot-value slotd 'boundp-function) object))
	207
	208	(defmethod (setf slot-value-using-class)
9adccb27	209	(value (class virtual-slots-class) (object standard-object)
94f15c3c	210	(slotd effective-virtual-slot-definition))
4d83a8a6	211	(funcall (slot-value slotd 'writer-function) value object))
	212
	213
94f15c3c	214	(defmethod validate-superclass
9adccb27	215	((class virtual-slots-class) (super standard-class))
94f15c3c	216	t)
	217
	218
	219	;;;; Proxy cache
	220
	221	(internal instance-cache)
	222	(defvar instance-cache (make-hash-table :test #'eql))
	223
	224	(defun cache-instance (instance)
	225	(setf
73572c12	226	(gethash (sap-int (proxy-location instance)) instance-cache)
73572c12	227	(make-weak-pointer instance)))
94f15c3c	228
94f15c3c	229	(defun find-cached-instance (location)
73572c12	230	(let ((ref (gethash (sap-int location) instance-cache)))
94f15c3c	231	(when ref
73572c12	232	(weak-pointer-value ref))))
94f15c3c	233
0f134a29	234	(defun instance-cached-p (location)
73572c12	235	(gethash (sap-int location) instance-cache))
0f134a29	236
94f15c3c	237	(defun remove-cached-instance (location)
73572c12	238	(remhash (sap-int location) instance-cache))
94f15c3c	239
9adccb27	240	;; For debuging
	241	(defun cached-instances ()
	242	(let ((instances ()))
	243	(maphash #'(lambda (location ref)
	244	(declare (ignore location))
73572c12	245	(push (weak-pointer-value ref) instances))
9adccb27	246	instance-cache)
	247	instances))
	248
94f15c3c	249
	250
	251	;;;; Proxy for alien instances
	252
9adccb27	253	(defclass proxy ()
9adccb27	254	((location :reader proxy-location :type system-area-pointer)))
94f15c3c	255
9adccb27	256	(defgeneric initialize-proxy (object &rest initargs))
	257	(defgeneric instance-finalizer (object))
	258	(defgeneric reference-foreign (class location))
	259	(defgeneric unreference-foreign (class location))
	260
3b167652	261	(defmethod reference-foreign ((name symbol) location)
	262	(reference-foreign (find-class name) location))
	263
	264	(defmethod unreference-foreign ((name symbol) location)
	265	(unreference-foreign (find-class name) location))
	266
9adccb27	267	(defmethod unreference-foreign :around ((class class) location)
	268	(unless (null-pointer-p location)
	269	;; (format t "Unreferencing ~A at ~A" (class-name class) location)
	270	;; (finish-output standard-output)
	271	(call-next-method)
	272	;; (write-line " done")
	273	;; (finish-output standard-output)
	274	))
94f15c3c	275
0f134a29	276	(defmethod print-object ((instance proxy) stream)
0f134a29	277	(print-unreadable-object (instance stream :type t :identity nil)
eeda1c2d	278	(when (slot-boundp instance 'location)
eeda1c2d	279	(format stream "at 0x~X" (sap-int (proxy-location instance))))))
94f15c3c	280
9adccb27	281	(defmethod initialize-instance :around ((instance proxy) &key location)
	282	(if location
	283	(setf (slot-value instance 'location) location)
	284	(call-next-method))
12d0437e	285	(cache-instance instance)
73572c12	286	(finalize instance (instance-finalizer instance))
9adccb27	287	instance)
94f15c3c	288
94f15c3c	289	(defmethod instance-finalizer ((instance proxy))
9adccb27	290	(let ((location (proxy-location instance))
	291	(class (class-of instance)))
	292	;; (unless (find-method #'unreference-foreign nil (list (class-of class) t) nil)
	293	;; (error "No matching method for UNREFERENCE-INSTANCE when called with class ~A" class))
	294	#'(lambda ()
1dbf4216	295	(remove-cached-instance location)
9adccb27	296	(unreference-foreign class location))))
12d0437e	297
94f15c3c	298
	299	;;;; Metaclass used for subclasses of proxy
	300
73572c12	301	(defgeneric most-specific-proxy-superclass (class))
	302	(defgeneric direct-proxy-superclass (class))
	303
	304
94f15c3c	305	(eval-when (:compile-toplevel :load-toplevel :execute)
9adccb27	306	(defclass proxy-class (virtual-slots-class)
9adccb27	307	((size :reader proxy-instance-size)))
94f15c3c	308
94f15c3c	309	(defclass direct-alien-slot-definition (direct-virtual-slot-definition)
12d0437e	310	((allocation :initform :alien)
12d0437e	311	(offset :reader slot-definition-offset :initarg :offset)))
94f15c3c	312
94f15c3c	313	(defclass effective-alien-slot-definition (effective-virtual-slot-definition)
4d83a8a6	314	((offset :reader slot-definition-offset :initarg :offset)))
12d0437e	315
94f15c3c	316	(defmethod most-specific-proxy-superclass ((class proxy-class))
	317	(find-if
	318	#'(lambda (class)
	319	(subtypep (class-name class) 'proxy))
4d83a8a6	320	(cdr (compute-class-precedence-list class))))
73572c12	321
12d0437e	322	(defmethod direct-proxy-superclass ((class proxy-class))
	323	(find-if
	324	#'(lambda (class)
	325	(subtypep (class-name class) 'proxy))
4d83a8a6	326	(class-direct-superclasses class)))
4d83a8a6	327
eeda1c2d	328	(defmethod shared-initialize ((class proxy-class) names &key size)
94f15c3c	329	(call-next-method)
12d0437e	330	(cond
4d83a8a6	331	(size (setf (slot-value class 'size) (first size)))
9adccb27	332	((slot-boundp class 'size) (slot-makunbound class 'size))))
4d83a8a6	333
4d83a8a6	334	(defmethod direct-slot-definition-class ((class proxy-class) &rest initargs)
94f15c3c	335	(case (getf initargs :allocation)
94f15c3c	336	((nil :alien) (find-class 'direct-alien-slot-definition))
94f15c3c	337	(t (call-next-method))))
4d83a8a6	338
4d83a8a6	339	(defmethod effective-slot-definition-class ((class proxy-class) &rest initargs)
94f15c3c	340	(case (getf initargs :allocation)
94f15c3c	341	(:alien (find-class 'effective-alien-slot-definition))
94f15c3c	342	(t (call-next-method))))
94f15c3c	343
4d83a8a6	344
	345	(defmethod compute-effective-slot-definition-initargs ((class proxy-class) direct-slotds)
	346	(if (eq (most-specific-slot-value direct-slotds 'allocation) :alien)
	347	(nconc
	348	(list :offset (most-specific-slot-value direct-slotds 'offset))
	349	(call-next-method))
	350	(call-next-method)))
	351
	352
	353	(defmethod initialize-internal-slot-functions ((slotd effective-alien-slot-definition))
	354	(with-slots (offset) slotd
9adccb27	355	(let ((type (slot-definition-type slotd)))
eeda1c2d	356	(unless (slot-boundp slotd 'getter)
9adccb27	357	(let ((reader (reader-function type)))
9adccb27	358	(setf
eeda1c2d	359	(slot-value slotd 'getter)
9adccb27	360	#'(lambda (object)
9adccb27	361	(funcall reader (proxy-location object) offset)))))
4d83a8a6	362
eeda1c2d	363	(unless (slot-boundp slotd 'setter)
9adccb27	364	(let ((writer (writer-function type))
	365	(destroy (destroy-function type)))
	366	(setf
eeda1c2d	367	(slot-value slotd 'setter)
9adccb27	368	#'(lambda (value object)
	369	(let ((location (proxy-location object)))
	370	(funcall destroy location offset) ; destroy old value
eeda1c2d	371	(funcall writer value location offset))))))))
eeda1c2d	372
4d83a8a6	373	(call-next-method))
	374
	375
4d83a8a6	376	;; TODO: call some C code to detect this a compile time
4d83a8a6	377	(defconstant +struct-alignmen+ 4)
94f15c3c	378
94f15c3c	379	(defmethod compute-slots ((class proxy-class))
4d83a8a6	380	(loop
3b167652	381	with offset = (let ((size-of-super-classes
	382	(proxy-instance-size
	383	(most-specific-proxy-superclass class))))
	384	(+ size-of-super-classes
	385	(mod size-of-super-classes +struct-alignmen+)))
4d83a8a6	386	with size = offset
	387	for slotd in (class-direct-slots class)
	388	when (eq (slot-definition-allocation slotd) :alien)
	389	do (if (not (slot-boundp slotd 'offset))
	390	(setf (slot-value slotd 'offset) offset)
	391	(setq offset (slot-value slotd 'offset)))
	392
	393	(incf offset (size-of (slot-definition-type slotd)))
	394	(incf offset (mod offset +struct-alignmen+))
	395	(setq size (max size offset))
	396
	397	finally (unless (slot-boundp class 'size)
	398	(setf (slot-value class 'size) size)))
94f15c3c	399	(call-next-method))
3e15002d	400
4d83a8a6	401
	402	(defmethod validate-superclass ((class proxy-class) (super standard-class))
	403	(subtypep (class-name super) 'proxy))
	404
9adccb27	405	(defmethod proxy-instance-size (class)
12d0437e	406	(declare (ignore class))
12d0437e	407	0)
47a11c16	408
	409	(defmethod proxy-instance-size ((class-name symbol))
	410	(proxy-instance-size (find-class class-name)))
4d83a8a6	411	)
4d83a8a6	412
9adccb27	413	(defmethod alien-type ((class proxy-class) &rest args)
	414	(declare (ignore class args))
	415	(alien-type 'pointer))
	416
	417	(defmethod size-of ((class proxy-class) &rest args)
	418	(declare (ignore class args))
	419	(size-of 'pointer))
	420
	421	(defmethod from-alien-form (location (class proxy-class) &rest args)
	422	(declare (ignore args))
	423	`(ensure-proxy-instance ',(class-name class) ,location))
	424
	425	(defmethod from-alien-function ((class proxy-class) &rest args)
	426	(declare (ignore args))
	427	#'(lambda (location)
	428	(ensure-proxy-instance class location)))
94f15c3c	429
9adccb27	430	(defmethod to-alien-form (instance (class proxy-class) &rest args)
	431	(declare (ignore class args))
	432	`(proxy-location ,instance))
94f15c3c	433
9adccb27	434	(defmethod to-alien-function ((class proxy-class) &rest args)
	435	(declare (ignore class args))
	436	#'proxy-location)
	437
9ca5565a	438	(defmethod copy-from-alien-form (location (class proxy-class) &rest args)
	439	(declare (ignore args))
	440	(let ((class-name (class-name class)))
	441	`(ensure-proxy-instance ',class-name
	442	(reference-foreign ',class-name ,location))))
	443
	444	(defmethod copy-from-alien-function ((class proxy-class) &rest args)
	445	(declare (ignore args))
	446	#'(lambda (location)
	447	(ensure-proxy-instance class (reference-foreign class location))))
	448
	449	(defmethod copy-to-alien-form (instance (class proxy-class) &rest args)
	450	(declare (ignore args))
	451	`(reference-foreign ',(class-name class) (proxy-location ,instance)))
	452
	453	(defmethod copy-to-alien-function ((class proxy-class) &rest args)
73572c12	454	(declare (ignore args))
9ca5565a	455	#'(lambda (instance)
	456	(reference-foreign class (proxy-location instance))))
	457
9adccb27	458	(defmethod writer-function ((class proxy-class) &rest args)
	459	(declare (ignore args))
	460	#'(lambda (instance location &optional (offset 0))
	461	(assert (null-pointer-p (sap-ref-sap location offset)))
	462	(setf
	463	(sap-ref-sap location offset)
	464	(reference-foreign class (proxy-location instance)))))
94f15c3c	465
9adccb27	466	(defmethod reader-function ((class proxy-class) &rest args)
	467	(declare (ignore args))
	468	#'(lambda (location &optional (offset 0))
9ca5565a	469	(let ((instance (sap-ref-sap location offset)))
	470	(unless (null-pointer-p instance)
	471	(ensure-proxy-instance class (reference-foreign class instance))))))
94f15c3c	472
9adccb27	473	(defmethod destroy-function ((class proxy-class) &rest args)
	474	(declare (ignore args))
	475	#'(lambda (location &optional (offset 0))
	476	(unreference-foreign class (sap-ref-sap location offset))))
	477
12b7df04	478	(defmethod unbound-value ((class proxy-class) &rest args)
47a11c16	479	(declare (ignore args))
12b7df04	480	(values t nil))
9adccb27	481
	482	(defgeneric ensure-proxy-instance (class location)
	483	(:documentation "Returns a proxy object representing the foreign object at the give location."))
	484
	485	(defmethod ensure-proxy-instance :around (class location)
	486	(unless (null-pointer-p location)
	487	(or
	488	(find-cached-instance location)
	489	(call-next-method))))
	490
	491	(defmethod ensure-proxy-instance ((class symbol) location)
	492	(ensure-proxy-instance (find-class class) location))
	493
	494	(defmethod ensure-proxy-instance ((class proxy-class) location)
	495	(make-instance class :location location))
94f15c3c	496
12d0437e	497
12d0437e	498	;;;; Superclasses for wrapping of C structures
94f15c3c	499
9adccb27	500	(defclass struct (proxy)
	501	()
	502	(:metaclass proxy-class))
94f15c3c	503
9adccb27	504	(defmethod initialize-instance ((struct struct) &rest initargs)
94f15c3c	505	(declare (ignore initargs))
ec1a4146	506	(unless (slot-boundp struct 'location)
	507	(let ((size (proxy-instance-size (class-of struct))))
	508	(if (zerop size)
	509	(error "~A has zero size" (class-of struct))
47a11c16	510	(setf (slot-value struct 'location) (allocate-memory size)))))
94f15c3c	511	(call-next-method))
	512
	513
9adccb27	514	;;;; Metaclasses used for subclasses of struct
	515
	516	(defclass struct-class (proxy-class)
	517	())
94f15c3c	518
9adccb27	519	(defmethod reference-foreign ((class struct-class) location)
	520	(copy-memory location (proxy-instance-size class)))
	521
	522	(defmethod unreference-foreign ((class struct-class) location)
12d0437e	523	(deallocate-memory location))
94f15c3c	524
94f15c3c	525
9adccb27	526	(defclass static-struct-class (struct-class)
9adccb27	527	())
94f15c3c	528
9adccb27	529	(defmethod reference-foreign ((class static-struct-class) location)
9adccb27	530	(declare (ignore class))
12d0437e	531	location)
94f15c3c	532
9adccb27	533	(defmethod unreference-foreign ((class static-struct-class) location)
9adccb27	534	(declare (ignore class location))
12d0437e	535	nil)