[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 1.16 2004-12-19 23:33:57 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
	((and 
	  (not (slot-boundp slotd 'unbound))
	  (not (slot-boundp slotd 'boundp)))
	 #'(lambda (object) (declare (ignore object)) t))  
	((slot-boundp slotd 'unbound)
	 (let ((unbound-value (slot-value slotd 'unbound)))
	   (lambda (object)
	     (not (eq (funcall getter-function object) unbound-value)))))
	((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))))))))))

      (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)))))
	(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 (system:sap-int (proxy-location instance)) *instance-cache*)
   (ext:make-weak-pointer instance)))

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

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

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

;; For debuging
(defun cached-instances ()
  (let ((instances ()))
    (maphash #'(lambda (location ref)
		 (declare (ignore location))
		 (push (ext: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)
  (ext: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

(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 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 class 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))))


(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
3b167652	18	;; $Id: proxy.lisp,v 1.16 2004-12-19 23:33:57 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)
4d83a8a6	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)
9adccb27	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
	87	(setq reader
	88	(mkbinding getter
	89	(slot-definition-type slotd) 'pointer)))
	90	(funcall reader (proxy-location object))))))))))
	91
4d83a8a6	92	(setf
eeda1c2d	93	(slot-value slotd 'boundp-function)
	94	(cond
	95	((and
	96	(not (slot-boundp slotd 'unbound))
	97	(not (slot-boundp slotd 'boundp)))
	98	#'(lambda (object) (declare (ignore object)) t))
	99	((slot-boundp slotd 'unbound)
	100	(let ((unbound-value (slot-value slotd 'unbound)))
	101	(lambda (object)
	102	(not (eq (funcall getter-function object) unbound-value)))))
	103	((let ((boundp (slot-value slotd 'boundp)))
	104	(etypecase boundp
	105	(function boundp)
	106	(symbol #'(lambda (object)
	107	(funcall boundp object)))
	108	(string (let ((reader ()))
	109	#'(lambda (object)
	110	(unless reader
	111	(setq reader
	112	(mkbinding boundp
	113	(slot-definition-type slotd) 'pointer)))
	114	(funcall reader (proxy-location object))))))))))
	115
	116	(setf
	117	(slot-value slotd 'reader-function)
	118	(cond
	119	((slot-boundp slotd 'unbound)
	120	(let ((unbound (slot-value slotd 'unbound))
	121	(slot-name (slot-definition-name slotd)))
	122	(lambda (object)
	123	(let ((value (funcall getter-function object)))
	124	(if (eq value unbound)
	125	(slot-unbound (class-of object) object slot-name)
	126	value)))))
	127	((slot-boundp slotd 'boundp)
	128	(let ((boundp-function (slot-value slotd 'boundp-function)))
	129	(lambda (object)
	130	(and
	131	(funcall boundp-function object)
	132	(funcall getter-function object)))))
	133	(getter-function)))))
	134
	135	(setf
	136	(slot-value slotd 'writer-function)
	137	(if (not (slot-boundp slotd 'setter))
	138	#'(lambda (object)
	139	(declare (ignore object))
	140	(error "Can't set slot: ~A" (slot-definition-name slotd)))
	141	(with-slots (setter) slotd
4d83a8a6	142	(etypecase setter
4d83a8a6	143	(function setter)
eeda1c2d	144	((or symbol cons)
	145	#'(lambda (value object)
	146	(funcall (fdefinition setter) value object)))
7d1ddc9e	147	(string
eeda1c2d	148	(let ((writer ()))
	149	(setf
	150	(slot-value slotd 'writer-function)
	151	#'(lambda (value object)
	152	(unless writer
	153	(setq writer
	154	(mkbinding setter 'nil 'pointer
	155	(slot-definition-type slotd))))
	156	(funcall writer (proxy-location object) value)))))))))
	157
4d83a8a6	158	(initialize-internal-slot-gfs (slot-definition-name slotd)))
	159
	160
	161
eeda1c2d	162	(defmethod compute-slot-accessor-info ((slotd effective-virtual-slot-definition) type gf)
4d83a8a6	163	nil)
4d83a8a6	164
9adccb27	165	(defmethod compute-effective-slot-definition-initargs ((class virtual-slots-class) direct-slotds)
eeda1c2d	166	(if (typep (first direct-slotds) 'direct-virtual-slot-definition)
	167	(let ((initargs ()))
	168	(let ((getter (most-specific-slot-value direct-slotds 'getter)))
	169	(unless (eq getter unbound-marker)
	170	(setf (getf initargs :getter) getter)))
	171	(let ((setter (most-specific-slot-value direct-slotds 'setter)))
	172	(unless (eq setter unbound-marker)
	173	(setf (getf initargs :setter) setter)))
	174	(let ((unbound (most-specific-slot-value direct-slotds 'unbound)))
	175	(unless (eq unbound unbound-marker)
	176	(setf (getf initargs :unbound) unbound)))
	177	(let ((boundp (most-specific-slot-value direct-slotds 'boundp)))
	178	(unless (eq boundp unbound-marker)
	179	(setf (getf initargs :boundp) boundp)))
	180	(nconc initargs (call-next-method)))
4d83a8a6	181	(call-next-method)))
4d83a8a6	182
94f15c3c	183
94f15c3c	184	(defmethod slot-value-using-class
9adccb27	185	((class virtual-slots-class) (object standard-object)
94f15c3c	186	(slotd effective-virtual-slot-definition))
4d83a8a6	187	(if (funcall (slot-value slotd 'boundp-function) object)
	188	(funcall (slot-value slotd 'reader-function) object)
	189	(slot-unbound class object (slot-definition-name slotd))))
94f15c3c	190
94f15c3c	191	(defmethod slot-boundp-using-class
9adccb27	192	((class virtual-slots-class) (object standard-object)
94f15c3c	193	(slotd effective-virtual-slot-definition))
4d83a8a6	194	(funcall (slot-value slotd 'boundp-function) object))
	195
	196	(defmethod (setf slot-value-using-class)
9adccb27	197	(value (class virtual-slots-class) (object standard-object)
94f15c3c	198	(slotd effective-virtual-slot-definition))
4d83a8a6	199	(funcall (slot-value slotd 'writer-function) value object))
	200
	201
94f15c3c	202	(defmethod validate-superclass
9adccb27	203	((class virtual-slots-class) (super standard-class))
94f15c3c	204	t)
	205
	206
	207	;;;; Proxy cache
	208
	209	(internal instance-cache)
	210	(defvar instance-cache (make-hash-table :test #'eql))
	211
	212	(defun cache-instance (instance)
	213	(setf
	214	(gethash (system:sap-int (proxy-location instance)) instance-cache)
	215	(ext:make-weak-pointer instance)))
	216
	217	(defun find-cached-instance (location)
	218	(let ((ref (gethash (system:sap-int location) instance-cache)))
	219	(when ref
	220	(ext:weak-pointer-value ref))))
	221
0f134a29	222	(defun instance-cached-p (location)
	223	(gethash (system:sap-int location) instance-cache))
	224
94f15c3c	225	(defun remove-cached-instance (location)
	226	(remhash (system:sap-int location) instance-cache))
	227
9adccb27	228	;; For debuging
	229	(defun cached-instances ()
	230	(let ((instances ()))
	231	(maphash #'(lambda (location ref)
	232	(declare (ignore location))
	233	(push (ext:weak-pointer-value ref) instances))
	234	instance-cache)
	235	instances))
	236
94f15c3c	237
	238
	239	;;;; Proxy for alien instances
	240
9adccb27	241	(defclass proxy ()
9adccb27	242	((location :reader proxy-location :type system-area-pointer)))
94f15c3c	243
9adccb27	244	(defgeneric initialize-proxy (object &rest initargs))
	245	(defgeneric instance-finalizer (object))
	246	(defgeneric reference-foreign (class location))
	247	(defgeneric unreference-foreign (class location))
	248
3b167652	249	(defmethod reference-foreign ((name symbol) location)
	250	(reference-foreign (find-class name) location))
	251
	252	(defmethod unreference-foreign ((name symbol) location)
	253	(unreference-foreign (find-class name) location))
	254
9adccb27	255	(defmethod unreference-foreign :around ((class class) location)
	256	(unless (null-pointer-p location)
	257	;; (format t "Unreferencing ~A at ~A" (class-name class) location)
	258	;; (finish-output standard-output)
	259	(call-next-method)
	260	;; (write-line " done")
	261	;; (finish-output standard-output)
	262	))
94f15c3c	263
0f134a29	264	(defmethod print-object ((instance proxy) stream)
0f134a29	265	(print-unreadable-object (instance stream :type t :identity nil)
eeda1c2d	266	(when (slot-boundp instance 'location)
eeda1c2d	267	(format stream "at 0x~X" (sap-int (proxy-location instance))))))
94f15c3c	268
9adccb27	269	(defmethod initialize-instance :around ((instance proxy) &key location)
	270	(if location
	271	(setf (slot-value instance 'location) location)
	272	(call-next-method))
12d0437e	273	(cache-instance instance)
9adccb27	274	(ext:finalize instance (instance-finalizer instance))
9adccb27	275	instance)
94f15c3c	276
94f15c3c	277	(defmethod instance-finalizer ((instance proxy))
9adccb27	278	(let ((location (proxy-location instance))
	279	(class (class-of instance)))
	280	;; (unless (find-method #'unreference-foreign nil (list (class-of class) t) nil)
	281	;; (error "No matching method for UNREFERENCE-INSTANCE when called with class ~A" class))
	282	#'(lambda ()
1dbf4216	283	(remove-cached-instance location)
9adccb27	284	(unreference-foreign class location))))
12d0437e	285
94f15c3c	286
	287	;;;; Metaclass used for subclasses of proxy
	288
	289	(eval-when (:compile-toplevel :load-toplevel :execute)
9adccb27	290	(defclass proxy-class (virtual-slots-class)
9adccb27	291	((size :reader proxy-instance-size)))
94f15c3c	292
94f15c3c	293	(defclass direct-alien-slot-definition (direct-virtual-slot-definition)
12d0437e	294	((allocation :initform :alien)
12d0437e	295	(offset :reader slot-definition-offset :initarg :offset)))
94f15c3c	296
94f15c3c	297	(defclass effective-alien-slot-definition (effective-virtual-slot-definition)
4d83a8a6	298	((offset :reader slot-definition-offset :initarg :offset)))
12d0437e	299
94f15c3c	300
	301	(defmethod most-specific-proxy-superclass ((class proxy-class))
	302	(find-if
	303	#'(lambda (class)
	304	(subtypep (class-name class) 'proxy))
4d83a8a6	305	(cdr (compute-class-precedence-list class))))
4d83a8a6	306
12d0437e	307	(defmethod direct-proxy-superclass ((class proxy-class))
	308	(find-if
	309	#'(lambda (class)
	310	(subtypep (class-name class) 'proxy))
4d83a8a6	311	(class-direct-superclasses class)))
4d83a8a6	312
eeda1c2d	313	(defmethod shared-initialize ((class proxy-class) names &key size)
94f15c3c	314	(call-next-method)
12d0437e	315	(cond
4d83a8a6	316	(size (setf (slot-value class 'size) (first size)))
9adccb27	317	((slot-boundp class 'size) (slot-makunbound class 'size))))
4d83a8a6	318
4d83a8a6	319	(defmethod direct-slot-definition-class ((class proxy-class) &rest initargs)
94f15c3c	320	(case (getf initargs :allocation)
94f15c3c	321	((nil :alien) (find-class 'direct-alien-slot-definition))
94f15c3c	322	(t (call-next-method))))
4d83a8a6	323
4d83a8a6	324	(defmethod effective-slot-definition-class ((class proxy-class) &rest initargs)
94f15c3c	325	(case (getf initargs :allocation)
94f15c3c	326	(:alien (find-class 'effective-alien-slot-definition))
94f15c3c	327	(t (call-next-method))))
94f15c3c	328
4d83a8a6	329
	330	(defmethod compute-effective-slot-definition-initargs ((class proxy-class) direct-slotds)
	331	(if (eq (most-specific-slot-value direct-slotds 'allocation) :alien)
	332	(nconc
	333	(list :offset (most-specific-slot-value direct-slotds 'offset))
	334	(call-next-method))
	335	(call-next-method)))
	336
	337
	338	(defmethod initialize-internal-slot-functions ((slotd effective-alien-slot-definition))
	339	(with-slots (offset) slotd
9adccb27	340	(let ((type (slot-definition-type slotd)))
eeda1c2d	341	(unless (slot-boundp slotd 'getter)
9adccb27	342	(let ((reader (reader-function type)))
9adccb27	343	(setf
eeda1c2d	344	(slot-value slotd 'getter)
9adccb27	345	#'(lambda (object)
9adccb27	346	(funcall reader (proxy-location object) offset)))))
4d83a8a6	347
eeda1c2d	348	(unless (slot-boundp slotd 'setter)
9adccb27	349	(let ((writer (writer-function type))
	350	(destroy (destroy-function type)))
	351	(setf
eeda1c2d	352	(slot-value slotd 'setter)
9adccb27	353	#'(lambda (value object)
	354	(let ((location (proxy-location object)))
	355	(funcall destroy location offset) ; destroy old value
eeda1c2d	356	(funcall writer value location offset))))))))
eeda1c2d	357
4d83a8a6	358	(call-next-method))
	359
	360
4d83a8a6	361	;; TODO: call some C code to detect this a compile time
4d83a8a6	362	(defconstant +struct-alignmen+ 4)
94f15c3c	363
94f15c3c	364	(defmethod compute-slots ((class proxy-class))
4d83a8a6	365	(loop
3b167652	366	with offset = (let ((size-of-super-classes
	367	(proxy-instance-size
	368	(most-specific-proxy-superclass class))))
	369	(+ size-of-super-classes
	370	(mod size-of-super-classes +struct-alignmen+)))
4d83a8a6	371	with size = offset
	372	for slotd in (class-direct-slots class)
	373	when (eq (slot-definition-allocation slotd) :alien)
	374	do (if (not (slot-boundp slotd 'offset))
	375	(setf (slot-value slotd 'offset) offset)
	376	(setq offset (slot-value slotd 'offset)))
	377
	378	(incf offset (size-of (slot-definition-type slotd)))
	379	(incf offset (mod offset +struct-alignmen+))
	380	(setq size (max size offset))
	381
	382	finally (unless (slot-boundp class 'size)
	383	(setf (slot-value class 'size) size)))
94f15c3c	384	(call-next-method))
3e15002d	385
4d83a8a6	386
	387	(defmethod validate-superclass ((class proxy-class) (super standard-class))
	388	(subtypep (class-name super) 'proxy))
	389
9adccb27	390	(defmethod proxy-instance-size (class)
12d0437e	391	(declare (ignore class))
12d0437e	392	0)
4d83a8a6	393	)
4d83a8a6	394
9adccb27	395	(defmethod alien-type ((class proxy-class) &rest args)
	396	(declare (ignore class args))
	397	(alien-type 'pointer))
	398
	399	(defmethod size-of ((class proxy-class) &rest args)
	400	(declare (ignore class args))
	401	(size-of 'pointer))
	402
	403	(defmethod from-alien-form (location (class proxy-class) &rest args)
	404	(declare (ignore args))
	405	`(ensure-proxy-instance ',(class-name class) ,location))
	406
	407	(defmethod from-alien-function ((class proxy-class) &rest args)
	408	(declare (ignore args))
	409	#'(lambda (location)
	410	(ensure-proxy-instance class location)))
94f15c3c	411
9adccb27	412	(defmethod to-alien-form (instance (class proxy-class) &rest args)
	413	(declare (ignore class args))
	414	`(proxy-location ,instance))
94f15c3c	415
9adccb27	416	(defmethod to-alien-function ((class proxy-class) &rest args)
	417	(declare (ignore class args))
	418	#'proxy-location)
	419
9ca5565a	420	(defmethod copy-from-alien-form (location (class proxy-class) &rest args)
	421	(declare (ignore args))
	422	(let ((class-name (class-name class)))
	423	`(ensure-proxy-instance ',class-name
	424	(reference-foreign ',class-name ,location))))
	425
	426	(defmethod copy-from-alien-function ((class proxy-class) &rest args)
	427	(declare (ignore args))
	428	#'(lambda (location)
	429	(ensure-proxy-instance class (reference-foreign class location))))
	430
	431	(defmethod copy-to-alien-form (instance (class proxy-class) &rest args)
	432	(declare (ignore args))
	433	`(reference-foreign ',(class-name class) (proxy-location ,instance)))
	434
	435	(defmethod copy-to-alien-function ((class proxy-class) &rest args)
	436	(declare (ignore class args))
	437	#'(lambda (instance)
	438	(reference-foreign class (proxy-location instance))))
	439
9adccb27	440	(defmethod writer-function ((class proxy-class) &rest args)
	441	(declare (ignore args))
	442	#'(lambda (instance location &optional (offset 0))
	443	(assert (null-pointer-p (sap-ref-sap location offset)))
	444	(setf
	445	(sap-ref-sap location offset)
	446	(reference-foreign class (proxy-location instance)))))
94f15c3c	447
9adccb27	448	(defmethod reader-function ((class proxy-class) &rest args)
	449	(declare (ignore args))
	450	#'(lambda (location &optional (offset 0))
9ca5565a	451	(let ((instance (sap-ref-sap location offset)))
	452	(unless (null-pointer-p instance)
	453	(ensure-proxy-instance class (reference-foreign class instance))))))
94f15c3c	454
9adccb27	455	(defmethod destroy-function ((class proxy-class) &rest args)
	456	(declare (ignore args))
	457	#'(lambda (location &optional (offset 0))
	458	(unreference-foreign class (sap-ref-sap location offset))))
	459
	460
	461	(defgeneric ensure-proxy-instance (class location)
	462	(:documentation "Returns a proxy object representing the foreign object at the give location."))
	463
	464	(defmethod ensure-proxy-instance :around (class location)
	465	(unless (null-pointer-p location)
	466	(or
	467	(find-cached-instance location)
	468	(call-next-method))))
	469
	470	(defmethod ensure-proxy-instance ((class symbol) location)
	471	(ensure-proxy-instance (find-class class) location))
	472
	473	(defmethod ensure-proxy-instance ((class proxy-class) location)
	474	(make-instance class :location location))
94f15c3c	475
12d0437e	476
12d0437e	477	;;;; Superclasses for wrapping of C structures
94f15c3c	478
9adccb27	479	(defclass struct (proxy)
	480	()
	481	(:metaclass proxy-class))
94f15c3c	482
9adccb27	483	(defmethod initialize-instance ((struct struct) &rest initargs)
94f15c3c	484	(declare (ignore initargs))
ec1a4146	485	(unless (slot-boundp struct 'location)
	486	(let ((size (proxy-instance-size (class-of struct))))
	487	(if (zerop size)
	488	(error "~A has zero size" (class-of struct))
	489	(setf (slot-value struct 'location) (allocate-memory size)))))
94f15c3c	490	(call-next-method))
	491
	492
9adccb27	493	;;;; Metaclasses used for subclasses of struct
	494
	495	(defclass struct-class (proxy-class)
	496	())
94f15c3c	497
9adccb27	498	(defmethod reference-foreign ((class struct-class) location)
	499	(copy-memory location (proxy-instance-size class)))
	500
	501	(defmethod unreference-foreign ((class struct-class) location)
12d0437e	502	(deallocate-memory location))
94f15c3c	503
94f15c3c	504
9adccb27	505	(defclass static-struct-class (struct-class)
9adccb27	506	())
94f15c3c	507
9adccb27	508	(defmethod reference-foreign ((class static-struct-class) location)
9adccb27	509	(declare (ignore class))
12d0437e	510	location)
94f15c3c	511
9adccb27	512	(defmethod unreference-foreign ((class static-struct-class) location)
9adccb27	513	(declare (ignore class location))
12d0437e	514	nil)