mdw@git.distorted.org.uk Git - clg/blob - glib/proxy.lisp

   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
  18 ;; $Id: proxy.lisp,v 1.10 2004-11-03 16:18:16 espen Exp $
  19
  20 (in-package "GLIB")
  21
  22 (import
  23 '(pcl::initialize-internal-slot-functions
  24   pcl::compute-effective-slot-definition-initargs
  25   pcl::compute-slot-accessor-info
  26   pcl::reader-function pcl::writer-function pcl::boundp-function))
  27
  28 ;;;; Superclass for all metaclasses implementing some sort of virtual slots
  29
  30 (eval-when (:compile-toplevel :load-toplevel :execute)
  31   (defclass virtual-slot-class (standard-class)
  32     ())
  33
  34   (defclass direct-virtual-slot-definition (standard-direct-slot-definition)
  35     ((setter :reader slot-definition-setter :initarg :setter)
  36      (getter :reader slot-definition-getter :initarg :getter)
  37      (boundp :reader slot-definition-boundp :initarg :boundp)))
  38
  39   (defclass effective-virtual-slot-definition (standard-effective-slot-definition)
  40     ((setter :reader slot-definition-setter :initarg :setter)
  41      (getter :reader slot-definition-getter :initarg :getter)
  42      (boundp :reader slot-definition-boundp :initarg :boundp)))
  43
  44   (defun most-specific-slot-value (instances slot &optional default)
  45     (let ((object (find-if
  46                    #'(lambda (ob)
  47                        (and (slot-exists-p ob slot) (slot-boundp ob slot)))
  48                    instances)))
  49       (if object
  50           (slot-value object slot)
  51           default)))
  52 )
  53
  54
  55
  56 (defmethod direct-slot-definition-class ((class virtual-slot-class) &rest initargs)
  57   (if (eq (getf initargs :allocation) :virtual)
  58       (find-class 'direct-virtual-slot-definition)
  59     (call-next-method)))
  60
  61 (defmethod effective-slot-definition-class ((class virtual-slot-class) &rest initargs)
  62   (if (eq (getf initargs :allocation) :virtual)
  63       (find-class 'effective-virtual-slot-definition)
  64     (call-next-method)))
  65
  66
  67 (defmethod initialize-internal-slot-functions ((slotd effective-virtual-slot-definition))
  68   (with-slots (getter setter boundp) slotd
  69     (unless (slot-boundp slotd 'reader-function)
  70       (setf
  71        (slot-value slotd 'reader-function)
  72        (etypecase getter
  73          (function getter)
  74          (null #'(lambda (object)
  75                    (declare (ignore object))
  76                    (error "Can't read slot: ~A" (slot-definition-name slotd))))
  77          (symbol #'(lambda (object)
  78                      (funcall getter object)))
  79          (string (let ((reader (mkbinding-late getter
  80                                 (slot-definition-type slotd) 'pointer)))
  81                    (setf (slot-value slotd 'reader-function)
  82                          #'(lambda (object)
  83                              (funcall reader (proxy-location object)))))))))
  84
  85     (unless (slot-boundp slotd 'writer-function)
  86       (setf
  87        (slot-value slotd 'writer-function)
  88        (etypecase setter
  89          (function setter)
  90          (null #'(lambda (object)
  91                    (declare (ignore object))
  92                    (error "Can't set slot: ~A" (slot-definition-name slotd))))
  93          ((or symbol cons) #'(lambda (value object)
  94                                (funcall (fdefinition setter) value object)))
  95          (string
  96           (let ((writer (mkbinding-late setter 'nil 'pointer
  97                          (slot-definition-type slotd))))
  98             (setf (slot-value slotd 'writer-function)
  99                   #'(lambda (value object)
 100                       (funcall writer (proxy-location object) value))))))))
 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
 120 (defmethod compute-effective-slot-definition-initargs ((class virtual-slot-class) direct-slotds)
 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
 129
 130 (defmethod slot-value-using-class
 131     ((class virtual-slot-class) (object standard-object)
 132      (slotd effective-virtual-slot-definition))
 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))))
 136
 137 (defmethod slot-boundp-using-class
 138     ((class virtual-slot-class) (object standard-object)
 139      (slotd effective-virtual-slot-definition))
 140   (funcall (slot-value slotd 'boundp-function) object))
 141
 142 (defmethod (setf slot-value-using-class)
 143     (value (class virtual-slot-class) (object standard-object)
 144      (slotd effective-virtual-slot-definition))
 145   (funcall (slot-value slotd 'writer-function) value object))
 146
 147
 148 (defmethod validate-superclass
 149     ((class virtual-slot-class) (super standard-class))
 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
 168 (defun instance-cached-p (location)
 169   (gethash (system:sap-int location) *instance-cache*))
 170
 171 (defun remove-cached-instance (location)
 172   (remhash (system:sap-int location) *instance-cache*))
 173
 174
 175
 176 ;;;; Proxy for alien instances
 177
 178 (eval-when (:compile-toplevel :load-toplevel :execute)
 179   (defclass proxy ()
 180     ((location :reader proxy-location :type system-area-pointer)))
 181
 182   (defgeneric initialize-proxy (object &rest initargs))
 183   (defgeneric instance-finalizer (object)))
 184
 185 (defmethod print-object ((instance proxy) stream)
 186   (print-unreadable-object (instance stream :type t :identity nil)
 187     (format stream "at 0x~X" (sap-int (proxy-location instance)))))
 188
 189
 190 (defmethod initialize-instance :after ((instance proxy)
 191                                        &rest initargs &key)
 192   (declare (ignore initargs))
 193   (cache-instance instance)
 194   (ext:finalize instance (instance-finalizer instance)))
 195
 196 (defmethod initialize-proxy ((instance proxy)
 197                              &rest initargs &key location weak-ref)
 198   (declare (ignore initargs))
 199   (setf
 200    (slot-value instance 'location)
 201    (if weak-ref
 202        (funcall
 203         (proxy-class-copy (class-of instance))
 204         (type-of instance) location)
 205      location))
 206   (cache-instance instance)
 207   (ext:finalize instance (instance-finalizer instance)))
 208
 209 (defmethod instance-finalizer ((instance proxy))
 210   (let ((class (class-of instance))
 211         (type (type-of instance))
 212         (location (proxy-location instance)))
 213     (declare (type symbol type) (type system-area-pointer location))
 214     (let ((free (proxy-class-free class)))
 215       #'(lambda ()
 216           (when (instance-cached-p location)
 217              (remove-cached-instance location)
 218              (funcall free type location))))))
 219
 220
 221 (deftype-method translate-type-spec proxy (type-spec)
 222   (declare (ignore type-spec))
 223   (translate-type-spec 'pointer))
 224
 225 (deftype-method size-of proxy (type-spec)
 226   (declare (ignore type-spec))
 227   (size-of 'pointer))
 228
 229 (deftype-method translate-from-alien
 230     proxy (type-spec location &optional weak-ref)
 231   `(let ((location ,location))
 232      (unless (null-pointer-p location)
 233        (ensure-proxy-instance ',type-spec location ,weak-ref))))
 234
 235 (deftype-method translate-to-alien
 236     proxy (type-spec instance &optional weak-ref)
 237   (if weak-ref
 238       `(proxy-location ,instance)
 239       (let ((copy (proxy-class-copy (find-class type-spec))))
 240         (if (symbolp copy)
 241             `(,copy ',type-spec (proxy-location ,instance))
 242         `(funcall ',copy ',type-spec (proxy-location ,instance))))))
 243
 244 (deftype-method unreference-alien proxy (type-spec location)
 245   (let ((free (proxy-class-free (find-class type-spec))))
 246     (if (symbolp free)
 247         `(,free ',type-spec ,location)
 248     `(funcall ',free ',type-spec ,location))))
 249
 250
 251 ;;;; Metaclass used for subclasses of proxy
 252
 253 (eval-when (:compile-toplevel :load-toplevel :execute)
 254   (defclass proxy-class (virtual-slot-class)
 255     ((size :reader proxy-class-size)
 256      (copy :reader proxy-class-copy)
 257      (free :reader proxy-class-free)))
 258
 259   (defclass direct-alien-slot-definition (direct-virtual-slot-definition)
 260     ((allocation :initform :alien)
 261      (offset :reader slot-definition-offset :initarg :offset)))
 262
 263   (defclass effective-alien-slot-definition (effective-virtual-slot-definition)
 264     ((offset :reader slot-definition-offset :initarg :offset)))
 265
 266
 267   (defmethod most-specific-proxy-superclass ((class proxy-class))
 268     (find-if
 269      #'(lambda (class)
 270          (subtypep (class-name class) 'proxy))
 271      (cdr (compute-class-precedence-list class))))
 272
 273   (defmethod direct-proxy-superclass ((class proxy-class))
 274     (find-if
 275      #'(lambda (class)
 276          (subtypep (class-name class) 'proxy))
 277      (class-direct-superclasses class)))
 278
 279   (defmethod shared-initialize ((class proxy-class) names
 280                                 &rest initargs &key size copy free)
 281     (declare (ignore initargs))
 282     (call-next-method)
 283     (cond
 284       (size (setf (slot-value class 'size) (first size)))
 285       ((slot-boundp class 'size) (slot-makunbound class 'size)))
 286     (cond
 287       (copy (setf (slot-value class 'copy) (first copy)))
 288       ((slot-boundp class 'copy) (slot-makunbound class 'copy)))
 289     (cond
 290       (free (setf (slot-value class 'free) (first free)))
 291       ((slot-boundp class 'free) (slot-makunbound class 'free))))
 292
 293   (defmethod shared-initialize :after ((class proxy-class) names &rest initargs)
 294     (let ((super (most-specific-proxy-superclass class)))
 295       (unless (or (not super) (eq super (find-class 'proxy)))
 296         (unless (or (slot-boundp class 'copy) (not (slot-boundp super 'copy)))
 297           (setf (slot-value class 'copy) (proxy-class-copy super)))
 298         (unless (or (slot-boundp class 'free) (not (slot-boundp super 'free)))
 299           (setf (slot-value class 'free) (proxy-class-free super))))))
 300
 301   (defmethod direct-slot-definition-class ((class proxy-class) &rest initargs)
 302     (case (getf initargs :allocation)
 303       ((nil :alien) (find-class 'direct-alien-slot-definition))
 304       (t (call-next-method))))
 305
 306   (defmethod effective-slot-definition-class ((class proxy-class) &rest initargs)
 307     (case (getf initargs :allocation)
 308       (:alien (find-class 'effective-alien-slot-definition))
 309       (t (call-next-method))))
 310
 311
 312   (defmethod compute-effective-slot-definition-initargs ((class proxy-class) direct-slotds)
 313     (if (eq (most-specific-slot-value direct-slotds 'allocation) :alien)
 314         (nconc
 315          (list :offset (most-specific-slot-value direct-slotds 'offset))
 316          (call-next-method))
 317       (call-next-method)))
 318
 319
 320   (defmethod initialize-internal-slot-functions ((slotd effective-alien-slot-definition))
 321     (with-slots (offset) slotd
 322       (let* ((type (slot-definition-type slotd))
 323              (reader (intern-reader-function type))
 324              (writer (intern-writer-function type))
 325              (destroy (intern-destroy-function type)))
 326         (unless (slot-boundp slotd 'reader-function)
 327           (setf
 328            (slot-value slotd 'reader-function)
 329            #'(lambda (object)
 330                (funcall reader (proxy-location object) offset))))
 331
 332         (unless (slot-boundp slotd 'writer-function)
 333           (setf
 334            (slot-value slotd 'writer-function)
 335            #'(lambda (value object)
 336                (let ((location (proxy-location object)))
 337                  (funcall destroy location offset)
 338                  (funcall writer value location offset)))))
 339
 340         (unless (slot-boundp slotd 'boundp-function)
 341           (setf
 342            (slot-value slotd 'boundp-function)
 343            #'(lambda (object)
 344                (declare (ignore object))
 345                t)))))
 346     (call-next-method))
 347
 348
 349   ;; TODO: call some C code to detect this a compile time
 350   (defconstant +struct-alignmen+ 4)
 351
 352   (defmethod compute-slots ((class proxy-class))
 353     ;; This stuff should really go somewhere else
 354     (loop
 355      with offset = (proxy-class-size (most-specific-proxy-superclass class))
 356      with size = offset
 357      for slotd in (class-direct-slots class)
 358      when (eq (slot-definition-allocation slotd) :alien)
 359      do (if (not (slot-boundp slotd 'offset))
 360             (setf (slot-value slotd 'offset) offset)
 361           (setq offset (slot-value slotd 'offset)))
 362
 363         (incf offset (size-of (slot-definition-type slotd)))
 364         (incf offset (mod offset +struct-alignmen+))
 365         (setq size (max size offset))
 366
 367      finally (unless (slot-boundp class 'size)
 368                (setf (slot-value class 'size) size)))
 369     (call-next-method))
 370
 371
 372   (defmethod validate-superclass ((class proxy-class) (super standard-class))
 373     (subtypep (class-name super) 'proxy))
 374
 375   (defmethod proxy-class-size (class)
 376     (declare (ignore class))
 377     0)
 378 )
 379
 380 (defgeneric make-proxy-instance (class location weak-ref
 381                                        &rest initargs &key));)
 382
 383 (defmethod make-proxy-instance ((class symbol) location weak-ref
 384                                 &rest initargs &key)
 385   (apply #'make-proxy-instance (find-class class) location weak-ref initargs))
 386
 387 (defmethod make-proxy-instance ((class proxy-class) location weak-ref
 388                                 &rest initargs &key)
 389   (let ((instance (allocate-instance class)))
 390     (apply
 391      #'initialize-proxy
 392      instance :location location :weak-ref weak-ref initargs)
 393     instance))
 394
 395 (defun ensure-proxy-instance (class location weak-ref &rest initargs)
 396   (or
 397    (find-cached-instance location)
 398    (apply #'make-proxy-instance class location weak-ref initargs)))
 399
 400
 401
 402 ;;;; Superclasses for wrapping of C structures
 403
 404 (eval-when (:compile-toplevel :load-toplevel :execute)
 405   (defclass struct (proxy)
 406     ()
 407     (:metaclass proxy-class)
 408     (:copy %copy-struct)
 409     (:free %free-struct)))
 410
 411 (defmethod initialize-instance ((structure struct) &rest initargs)
 412   (declare (ignore initargs))
 413   (setf
 414    (slot-value structure 'location)
 415    (allocate-memory (proxy-class-size (class-of structure))))
 416   (call-next-method))
 417
 418
 419 (defun %copy-struct (type location)
 420   (copy-memory location (proxy-class-size (find-class type))))
 421
 422 (defun %free-struct (type location)
 423   (declare (ignore type))
 424   (deallocate-memory location))
 425
 426
 427 ;(eval-when (:compile-toplevel :load-toplevel :execute)
 428   (defclass static (struct)
 429     ()
 430     (:metaclass proxy-class)
 431     (:copy %copy-static)
 432     (:free %free-static));)
 433
 434 (defun %copy-static (type location)
 435   (declare (ignore type))
 436   location)
 437
 438 (defun %free-static (type location)
 439   (declare (ignore type location))
 440   nil)