[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 1.12 2004-11-09 10:10:59 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)
     (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)
     (boundp :reader slot-definition-boundp :initarg :boundp)))

  (defun most-specific-slot-value (instances slot &optional default)
    (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))
  (with-slots (getter setter boundp) slotd
    (unless (slot-boundp slotd 'reader-function)
      (setf 
       (slot-value slotd 'reader-function)
       (etypecase getter
	 (function getter)
	 (null #'(lambda (object)
		   (declare (ignore object))
		   (error "Can't read slot: ~A" (slot-definition-name slotd))))
	 (symbol #'(lambda (object)
		     (funcall getter object)))
	 (string ;(let ()(reader  (mkbinding getter 
;; 				(slot-definition-type slotd) 'pointer)))
		   (setf (slot-value slotd 'reader-function)
			 #'(lambda (object)
			     (let ((reader
				(mkbinding getter 
				 (slot-definition-type slotd) 'pointer)))
			     (funcall reader (proxy-location object)))))))))

    (unless (slot-boundp slotd 'writer-function)
      (setf 
       (slot-value slotd 'writer-function)
       (etypecase setter
	 (function setter)
	 (null #'(lambda (object)
		   (declare (ignore object))
		   (error "Can't set slot: ~A" (slot-definition-name slotd))))
	 ((or symbol cons) #'(lambda (value object)
			       (funcall (fdefinition setter) value object)))
	 (string
	  (let ((writer ()));; (mkbinding setter 'nil 'pointer 
;; 			 (slot-definition-type slotd))))
	    (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))))))))

    (unless (slot-boundp slotd 'boundp-function)
      (setf 
       (slot-value slotd 'boundp-function)
       (etypecase boundp
	 (function boundp)
	 (null #'(lambda (object)
		   (declare (ignore object))
		   t))
	 (symbol #'(lambda (object)
		     (funcall boundp object)))))))
  (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 (eq (most-specific-slot-value direct-slotds 'allocation) :virtual)
      (nconc 
       (list :getter (most-specific-slot-value direct-slotds 'getter)
	     :setter (most-specific-slot-value direct-slotds 'setter)
	     :boundp (most-specific-slot-value direct-slotds 'boundp))
       (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 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)
    (format stream "at 0x~X" (sap-int (proxy-location instance)))))

(defmethod print-object ((instance proxy) stream)
  (print-unreadable-object (instance stream :type t :identity nil)
    (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
				&rest initargs &key size)
    (declare (ignore initargs))
    (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 'reader-function)
	  (let ((reader (reader-function type)))
	    (setf 
	     (slot-value slotd 'reader-function)
	     #'(lambda (object)
		 (funcall reader (proxy-location object) offset)))))

	(unless (slot-boundp slotd 'writer-function)
	  (let ((writer (writer-function type))
		(destroy (destroy-function type)))
	    (setf 
	     (slot-value slotd 'writer-function)
	     #'(lambda (value object)
		 (let ((location (proxy-location object)))
		   (funcall destroy location offset) ; destroy old value
		   (funcall writer value location offset))))))

	(unless (slot-boundp slotd 'boundp-function)
	  (setf 
	   (slot-value slotd 'boundp-function)
	   #'(lambda (object)
	       (declare (ignore object))
	       t)))))
    (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 = (proxy-instance-size (most-specific-proxy-superclass class))
     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 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))
      (ensure-proxy-instance class (sap-ref-sap location offset))))

(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))
  (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))

(defmethod reader-function ((class struct-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))))))


(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
1dbf4216	18	;; $Id: proxy.lisp,v 1.12 2004-11-09 10:10:59 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)
4d83a8a6	31	(boundp :reader slot-definition-boundp :initarg :boundp)))
94f15c3c	32
4d83a8a6	33	(defclass effective-virtual-slot-definition (standard-effective-slot-definition)
	34	((setter :reader slot-definition-setter :initarg :setter)
	35	(getter :reader slot-definition-getter :initarg :getter)
	36	(boundp :reader slot-definition-boundp :initarg :boundp)))
	37
	38	(defun most-specific-slot-value (instances slot &optional default)
	39	(let ((object (find-if
	40	#'(lambda (ob)
	41	(and (slot-exists-p ob slot) (slot-boundp ob slot)))
	42	instances)))
	43	(if object
	44	(slot-value object slot)
9adccb27	45	default))))
4d83a8a6	46
94f15c3c	47
94f15c3c	48
9adccb27	49	(defmethod direct-slot-definition-class ((class virtual-slots-class) &rest initargs)
94f15c3c	50	(if (eq (getf initargs :allocation) :virtual)
	51	(find-class 'direct-virtual-slot-definition)
	52	(call-next-method)))
	53
9adccb27	54	(defmethod effective-slot-definition-class ((class virtual-slots-class) &rest initargs)
94f15c3c	55	(if (eq (getf initargs :allocation) :virtual)
	56	(find-class 'effective-virtual-slot-definition)
	57	(call-next-method)))
	58
4d83a8a6	59
	60	(defmethod initialize-internal-slot-functions ((slotd effective-virtual-slot-definition))
	61	(with-slots (getter setter boundp) slotd
	62	(unless (slot-boundp slotd 'reader-function)
	63	(setf
	64	(slot-value slotd 'reader-function)
	65	(etypecase getter
	66	(function getter)
	67	(null #'(lambda (object)
	68	(declare (ignore object))
	69	(error "Can't read slot: ~A" (slot-definition-name slotd))))
	70	(symbol #'(lambda (object)
7d1ddc9e	71	(funcall getter object)))
9adccb27	72	(string ;(let ()(reader (mkbinding getter
9adccb27	73	;; (slot-definition-type slotd) 'pointer)))
7d1ddc9e	74	(setf (slot-value slotd 'reader-function)
7d1ddc9e	75	#'(lambda (object)
9adccb27	76	(let ((reader
	77	(mkbinding getter
	78	(slot-definition-type slotd) 'pointer)))
7d1ddc9e	79	(funcall reader (proxy-location object)))))))))
4d83a8a6	80
	81	(unless (slot-boundp slotd 'writer-function)
	82	(setf
	83	(slot-value slotd 'writer-function)
	84	(etypecase setter
	85	(function setter)
	86	(null #'(lambda (object)
	87	(declare (ignore object))
	88	(error "Can't set slot: ~A" (slot-definition-name slotd))))
	89	((or symbol cons) #'(lambda (value object)
7d1ddc9e	90	(funcall (fdefinition setter) value object)))
7d1ddc9e	91	(string
9adccb27	92	(let ((writer ()));; (mkbinding setter 'nil 'pointer
9adccb27	93	;; (slot-definition-type slotd))))
7d1ddc9e	94	(setf (slot-value slotd 'writer-function)
7d1ddc9e	95	#'(lambda (value object)
9adccb27	96	(unless writer
	97	(setq writer
	98	(mkbinding setter 'nil 'pointer
	99	(slot-definition-type slotd))))
7d1ddc9e	100	(funcall writer (proxy-location object) value))))))))
4d83a8a6	101
	102	(unless (slot-boundp slotd 'boundp-function)
	103	(setf
	104	(slot-value slotd 'boundp-function)
	105	(etypecase boundp
	106	(function boundp)
	107	(null #'(lambda (object)
	108	(declare (ignore object))
	109	t))
	110	(symbol #'(lambda (object)
	111	(funcall boundp object)))))))
	112	(initialize-internal-slot-gfs (slot-definition-name slotd)))
	113
	114
	115
	116	(defmethod compute-slot-accessor-info ((slotd effective-virtual-slot-definition)
	117	type gf)
	118	nil)
	119
9adccb27	120	(defmethod compute-effective-slot-definition-initargs ((class virtual-slots-class) direct-slotds)
4d83a8a6	121	(if (eq (most-specific-slot-value direct-slotds 'allocation) :virtual)
	122	(nconc
	123	(list :getter (most-specific-slot-value direct-slotds 'getter)
	124	:setter (most-specific-slot-value direct-slotds 'setter)
	125	:boundp (most-specific-slot-value direct-slotds 'boundp))
	126	(call-next-method))
	127	(call-next-method)))
	128
94f15c3c	129
94f15c3c	130	(defmethod slot-value-using-class
9adccb27	131	((class virtual-slots-class) (object standard-object)
94f15c3c	132	(slotd effective-virtual-slot-definition))
4d83a8a6	133	(if (funcall (slot-value slotd 'boundp-function) object)
	134	(funcall (slot-value slotd 'reader-function) object)
	135	(slot-unbound class object (slot-definition-name slotd))))
94f15c3c	136
94f15c3c	137	(defmethod slot-boundp-using-class
9adccb27	138	((class virtual-slots-class) (object standard-object)
94f15c3c	139	(slotd effective-virtual-slot-definition))
4d83a8a6	140	(funcall (slot-value slotd 'boundp-function) object))
	141
	142	(defmethod (setf slot-value-using-class)
9adccb27	143	(value (class virtual-slots-class) (object standard-object)
94f15c3c	144	(slotd effective-virtual-slot-definition))
4d83a8a6	145	(funcall (slot-value slotd 'writer-function) value object))
	146
	147
94f15c3c	148	(defmethod validate-superclass
9adccb27	149	((class virtual-slots-class) (super standard-class))
94f15c3c	150	t)
	151
	152
	153	;;;; Proxy cache
	154
	155	(internal instance-cache)
	156	(defvar instance-cache (make-hash-table :test #'eql))
	157
	158	(defun cache-instance (instance)
	159	(setf
	160	(gethash (system:sap-int (proxy-location instance)) instance-cache)
	161	(ext:make-weak-pointer instance)))
	162
	163	(defun find-cached-instance (location)
	164	(let ((ref (gethash (system:sap-int location) instance-cache)))
	165	(when ref
	166	(ext:weak-pointer-value ref))))
	167
0f134a29	168	(defun instance-cached-p (location)
	169	(gethash (system:sap-int location) instance-cache))
	170
94f15c3c	171	(defun remove-cached-instance (location)
	172	(remhash (system:sap-int location) instance-cache))
	173
9adccb27	174	;; For debuging
	175	(defun cached-instances ()
	176	(let ((instances ()))
	177	(maphash #'(lambda (location ref)
	178	(declare (ignore location))
	179	(push (ext:weak-pointer-value ref) instances))
	180	instance-cache)
	181	instances))
	182
94f15c3c	183
	184
	185	;;;; Proxy for alien instances
	186
9adccb27	187	(defclass proxy ()
9adccb27	188	((location :reader proxy-location :type system-area-pointer)))
94f15c3c	189
9adccb27	190	(defgeneric initialize-proxy (object &rest initargs))
	191	(defgeneric instance-finalizer (object))
	192	(defgeneric reference-foreign (class location))
	193	(defgeneric unreference-foreign (class location))
	194
	195	(defmethod unreference-foreign :around ((class class) location)
	196	(unless (null-pointer-p location)
	197	;; (format t "Unreferencing ~A at ~A" (class-name class) location)
	198	;; (finish-output standard-output)
	199	(call-next-method)
	200	;; (write-line " done")
	201	;; (finish-output standard-output)
	202	))
94f15c3c	203
0f134a29	204	(defmethod print-object ((instance proxy) stream)
	205	(print-unreadable-object (instance stream :type t :identity nil)
	206	(format stream "at 0x~X" (sap-int (proxy-location instance)))))
	207
9adccb27	208	(defmethod print-object ((instance proxy) stream)
	209	(print-unreadable-object (instance stream :type t :identity nil)
	210	(format stream "at 0x~X" (sap-int (proxy-location instance)))))
94f15c3c	211
94f15c3c	212
9adccb27	213	(defmethod initialize-instance :around ((instance proxy) &key location)
	214	(if location
	215	(setf (slot-value instance 'location) location)
	216	(call-next-method))
12d0437e	217	(cache-instance instance)
9adccb27	218	(ext:finalize instance (instance-finalizer instance))
9adccb27	219	instance)
94f15c3c	220
94f15c3c	221	(defmethod instance-finalizer ((instance proxy))
9adccb27	222	(let ((location (proxy-location instance))
	223	(class (class-of instance)))
	224	;; (unless (find-method #'unreference-foreign nil (list (class-of class) t) nil)
	225	;; (error "No matching method for UNREFERENCE-INSTANCE when called with class ~A" class))
	226	#'(lambda ()
1dbf4216	227	(remove-cached-instance location)
9adccb27	228	(unreference-foreign class location))))
12d0437e	229
94f15c3c	230
	231	;;;; Metaclass used for subclasses of proxy
	232
	233	(eval-when (:compile-toplevel :load-toplevel :execute)
9adccb27	234	(defclass proxy-class (virtual-slots-class)
9adccb27	235	((size :reader proxy-instance-size)))
94f15c3c	236
94f15c3c	237	(defclass direct-alien-slot-definition (direct-virtual-slot-definition)
12d0437e	238	((allocation :initform :alien)
12d0437e	239	(offset :reader slot-definition-offset :initarg :offset)))
94f15c3c	240
94f15c3c	241	(defclass effective-alien-slot-definition (effective-virtual-slot-definition)
4d83a8a6	242	((offset :reader slot-definition-offset :initarg :offset)))
12d0437e	243
94f15c3c	244
	245	(defmethod most-specific-proxy-superclass ((class proxy-class))
	246	(find-if
	247	#'(lambda (class)
	248	(subtypep (class-name class) 'proxy))
4d83a8a6	249	(cdr (compute-class-precedence-list class))))
4d83a8a6	250
12d0437e	251	(defmethod direct-proxy-superclass ((class proxy-class))
	252	(find-if
	253	#'(lambda (class)
	254	(subtypep (class-name class) 'proxy))
4d83a8a6	255	(class-direct-superclasses class)))
4d83a8a6	256
94f15c3c	257	(defmethod shared-initialize ((class proxy-class) names
9adccb27	258	&rest initargs &key size)
94f15c3c	259	(declare (ignore initargs))
94f15c3c	260	(call-next-method)
12d0437e	261	(cond
4d83a8a6	262	(size (setf (slot-value class 'size) (first size)))
9adccb27	263	((slot-boundp class 'size) (slot-makunbound class 'size))))
4d83a8a6	264
4d83a8a6	265	(defmethod direct-slot-definition-class ((class proxy-class) &rest initargs)
94f15c3c	266	(case (getf initargs :allocation)
94f15c3c	267	((nil :alien) (find-class 'direct-alien-slot-definition))
94f15c3c	268	(t (call-next-method))))
4d83a8a6	269
4d83a8a6	270	(defmethod effective-slot-definition-class ((class proxy-class) &rest initargs)
94f15c3c	271	(case (getf initargs :allocation)
94f15c3c	272	(:alien (find-class 'effective-alien-slot-definition))
94f15c3c	273	(t (call-next-method))))
94f15c3c	274
4d83a8a6	275
	276	(defmethod compute-effective-slot-definition-initargs ((class proxy-class) direct-slotds)
	277	(if (eq (most-specific-slot-value direct-slotds 'allocation) :alien)
	278	(nconc
	279	(list :offset (most-specific-slot-value direct-slotds 'offset))
	280	(call-next-method))
	281	(call-next-method)))
	282
	283
	284	(defmethod initialize-internal-slot-functions ((slotd effective-alien-slot-definition))
	285	(with-slots (offset) slotd
9adccb27	286	(let ((type (slot-definition-type slotd)))
4d83a8a6	287	(unless (slot-boundp slotd 'reader-function)
9adccb27	288	(let ((reader (reader-function type)))
	289	(setf
	290	(slot-value slotd 'reader-function)
	291	#'(lambda (object)
	292	(funcall reader (proxy-location object) offset)))))
4d83a8a6	293
4d83a8a6	294	(unless (slot-boundp slotd 'writer-function)
9adccb27	295	(let ((writer (writer-function type))
	296	(destroy (destroy-function type)))
	297	(setf
	298	(slot-value slotd 'writer-function)
	299	#'(lambda (value object)
	300	(let ((location (proxy-location object)))
	301	(funcall destroy location offset) ; destroy old value
	302	(funcall writer value location offset))))))
4d83a8a6	303
	304	(unless (slot-boundp slotd 'boundp-function)
	305	(setf
	306	(slot-value slotd 'boundp-function)
	307	#'(lambda (object)
	308	(declare (ignore object))
	309	t)))))
	310	(call-next-method))
	311
	312
4d83a8a6	313	;; TODO: call some C code to detect this a compile time
4d83a8a6	314	(defconstant +struct-alignmen+ 4)
94f15c3c	315
94f15c3c	316	(defmethod compute-slots ((class proxy-class))
4d83a8a6	317	(loop
9adccb27	318	with offset = (proxy-instance-size (most-specific-proxy-superclass class))
4d83a8a6	319	with size = offset
	320	for slotd in (class-direct-slots class)
	321	when (eq (slot-definition-allocation slotd) :alien)
	322	do (if (not (slot-boundp slotd 'offset))
	323	(setf (slot-value slotd 'offset) offset)
	324	(setq offset (slot-value slotd 'offset)))
	325
	326	(incf offset (size-of (slot-definition-type slotd)))
	327	(incf offset (mod offset +struct-alignmen+))
	328	(setq size (max size offset))
	329
	330	finally (unless (slot-boundp class 'size)
	331	(setf (slot-value class 'size) size)))
94f15c3c	332	(call-next-method))
3e15002d	333
4d83a8a6	334
	335	(defmethod validate-superclass ((class proxy-class) (super standard-class))
	336	(subtypep (class-name super) 'proxy))
	337
9adccb27	338	(defmethod proxy-instance-size (class)
12d0437e	339	(declare (ignore class))
12d0437e	340	0)
4d83a8a6	341	)
4d83a8a6	342
9adccb27	343	(defmethod alien-type ((class proxy-class) &rest args)
	344	(declare (ignore class args))
	345	(alien-type 'pointer))
	346
	347	(defmethod size-of ((class proxy-class) &rest args)
	348	(declare (ignore class args))
	349	(size-of 'pointer))
	350
	351	(defmethod from-alien-form (location (class proxy-class) &rest args)
	352	(declare (ignore args))
	353	`(ensure-proxy-instance ',(class-name class) ,location))
	354
	355	(defmethod from-alien-function ((class proxy-class) &rest args)
	356	(declare (ignore args))
	357	#'(lambda (location)
	358	(ensure-proxy-instance class location)))
94f15c3c	359
9adccb27	360	(defmethod to-alien-form (instance (class proxy-class) &rest args)
	361	(declare (ignore class args))
	362	`(proxy-location ,instance))
94f15c3c	363
9adccb27	364	(defmethod to-alien-function ((class proxy-class) &rest args)
	365	(declare (ignore class args))
	366	#'proxy-location)
	367
	368	(defmethod writer-function ((class proxy-class) &rest args)
	369	(declare (ignore args))
	370	#'(lambda (instance location &optional (offset 0))
	371	(assert (null-pointer-p (sap-ref-sap location offset)))
	372	(setf
	373	(sap-ref-sap location offset)
	374	(reference-foreign class (proxy-location instance)))))
94f15c3c	375
9adccb27	376	(defmethod reader-function ((class proxy-class) &rest args)
	377	(declare (ignore args))
	378	#'(lambda (location &optional (offset 0))
	379	(ensure-proxy-instance class (sap-ref-sap location offset))))
94f15c3c	380
9adccb27	381	(defmethod destroy-function ((class proxy-class) &rest args)
	382	(declare (ignore args))
	383	#'(lambda (location &optional (offset 0))
	384	(unreference-foreign class (sap-ref-sap location offset))))
	385
	386
	387	(defgeneric ensure-proxy-instance (class location)
	388	(:documentation "Returns a proxy object representing the foreign object at the give location."))
	389
	390	(defmethod ensure-proxy-instance :around (class location)
	391	(unless (null-pointer-p location)
	392	(or
	393	(find-cached-instance location)
	394	(call-next-method))))
	395
	396	(defmethod ensure-proxy-instance ((class symbol) location)
	397	(ensure-proxy-instance (find-class class) location))
	398
	399	(defmethod ensure-proxy-instance ((class proxy-class) location)
	400	(make-instance class :location location))
94f15c3c	401
12d0437e	402
12d0437e	403	;;;; Superclasses for wrapping of C structures
94f15c3c	404
9adccb27	405	(defclass struct (proxy)
	406	()
	407	(:metaclass proxy-class))
94f15c3c	408
9adccb27	409	(defmethod initialize-instance ((struct struct) &rest initargs)
94f15c3c	410	(declare (ignore initargs))
1dbf4216	411	(let ((size (proxy-instance-size (class-of struct))))
	412	(if (zerop size)
	413	(error "~A has zero size" (class-of struct))
	414	(setf (slot-value struct 'location) (allocate-memory size))))
94f15c3c	415	(call-next-method))
	416
	417
9adccb27	418	;;;; Metaclasses used for subclasses of struct
	419
	420	(defclass struct-class (proxy-class)
	421	())
94f15c3c	422
9adccb27	423	(defmethod reference-foreign ((class struct-class) location)
	424	(copy-memory location (proxy-instance-size class)))
	425
	426	(defmethod unreference-foreign ((class struct-class) location)
12d0437e	427	(deallocate-memory location))
94f15c3c	428
9adccb27	429	(defmethod reader-function ((class struct-class) &rest args)
	430	(declare (ignore args))
	431	#'(lambda (location &optional (offset 0))
	432	(let ((instance (sap-ref-sap location offset)))
	433	(unless (null-pointer-p instance)
	434	(ensure-proxy-instance class (reference-foreign class instance))))))
	435
94f15c3c	436
9adccb27	437	(defclass static-struct-class (struct-class)
9adccb27	438	())
94f15c3c	439
9adccb27	440	(defmethod reference-foreign ((class static-struct-class) location)
9adccb27	441	(declare (ignore class))
12d0437e	442	location)
94f15c3c	443
9adccb27	444	(defmethod unreference-foreign ((class static-struct-class) location)
9adccb27	445	(declare (ignore class location))
12d0437e	446	nil)