Subclasses of STRUCT may now allocate foreign memory
[clg] / 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 1.13 2004-11-15 19:20:55 espen Exp $
19
20 (in-package "GLIB")
21
22 ;;;; Superclass for all metaclasses implementing some sort of virtual slots
23
24 (eval-when (:compile-toplevel :load-toplevel :execute)
25 (defclass virtual-slots-class (standard-class)
26 ())
27
28 (defclass direct-virtual-slot-definition (standard-direct-slot-definition)
29 ((setter :reader slot-definition-setter :initarg :setter)
30 (getter :reader slot-definition-getter :initarg :getter)
31 (boundp :reader slot-definition-boundp :initarg :boundp)))
32
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)
45 default))))
46
47
48
49 (defmethod direct-slot-definition-class ((class virtual-slots-class) &rest initargs)
50 (if (eq (getf initargs :allocation) :virtual)
51 (find-class 'direct-virtual-slot-definition)
52 (call-next-method)))
53
54 (defmethod effective-slot-definition-class ((class virtual-slots-class) &rest initargs)
55 (if (eq (getf initargs :allocation) :virtual)
56 (find-class 'effective-virtual-slot-definition)
57 (call-next-method)))
58
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)
71 (funcall getter object)))
72 (string ;(let ()(reader (mkbinding getter
73 ;; (slot-definition-type slotd) 'pointer)))
74 (setf (slot-value slotd 'reader-function)
75 #'(lambda (object)
76 (let ((reader
77 (mkbinding getter
78 (slot-definition-type slotd) 'pointer)))
79 (funcall reader (proxy-location object)))))))))
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)
90 (funcall (fdefinition setter) value object)))
91 (string
92 (let ((writer ()));; (mkbinding setter 'nil 'pointer
93 ;; (slot-definition-type slotd))))
94 (setf (slot-value slotd 'writer-function)
95 #'(lambda (value object)
96 (unless writer
97 (setq writer
98 (mkbinding setter 'nil 'pointer
99 (slot-definition-type slotd))))
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-slots-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-slots-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-slots-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-slots-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-slots-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 ;; 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
183
184
185 ;;;; Proxy for alien instances
186
187 (defclass proxy ()
188 ((location :reader proxy-location :type system-area-pointer)))
189
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 ))
203
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
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)))))
211
212
213 (defmethod initialize-instance :around ((instance proxy) &key location)
214 (if location
215 (setf (slot-value instance 'location) location)
216 (call-next-method))
217 (cache-instance instance)
218 (ext:finalize instance (instance-finalizer instance))
219 instance)
220
221 (defmethod instance-finalizer ((instance proxy))
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 ()
227 (remove-cached-instance location)
228 (unreference-foreign class location))))
229
230
231 ;;;; Metaclass used for subclasses of proxy
232
233 (eval-when (:compile-toplevel :load-toplevel :execute)
234 (defclass proxy-class (virtual-slots-class)
235 ((size :reader proxy-instance-size)))
236
237 (defclass direct-alien-slot-definition (direct-virtual-slot-definition)
238 ((allocation :initform :alien)
239 (offset :reader slot-definition-offset :initarg :offset)))
240
241 (defclass effective-alien-slot-definition (effective-virtual-slot-definition)
242 ((offset :reader slot-definition-offset :initarg :offset)))
243
244
245 (defmethod most-specific-proxy-superclass ((class proxy-class))
246 (find-if
247 #'(lambda (class)
248 (subtypep (class-name class) 'proxy))
249 (cdr (compute-class-precedence-list class))))
250
251 (defmethod direct-proxy-superclass ((class proxy-class))
252 (find-if
253 #'(lambda (class)
254 (subtypep (class-name class) 'proxy))
255 (class-direct-superclasses class)))
256
257 (defmethod shared-initialize ((class proxy-class) names
258 &rest initargs &key size)
259 (declare (ignore initargs))
260 (call-next-method)
261 (cond
262 (size (setf (slot-value class 'size) (first size)))
263 ((slot-boundp class 'size) (slot-makunbound class 'size))))
264
265 (defmethod direct-slot-definition-class ((class proxy-class) &rest initargs)
266 (case (getf initargs :allocation)
267 ((nil :alien) (find-class 'direct-alien-slot-definition))
268 (t (call-next-method))))
269
270 (defmethod effective-slot-definition-class ((class proxy-class) &rest initargs)
271 (case (getf initargs :allocation)
272 (:alien (find-class 'effective-alien-slot-definition))
273 (t (call-next-method))))
274
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
286 (let ((type (slot-definition-type slotd)))
287 (unless (slot-boundp slotd 'reader-function)
288 (let ((reader (reader-function type)))
289 (setf
290 (slot-value slotd 'reader-function)
291 #'(lambda (object)
292 (funcall reader (proxy-location object) offset)))))
293
294 (unless (slot-boundp slotd 'writer-function)
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))))))
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
313 ;; TODO: call some C code to detect this a compile time
314 (defconstant +struct-alignmen+ 4)
315
316 (defmethod compute-slots ((class proxy-class))
317 (loop
318 with offset = (proxy-instance-size (most-specific-proxy-superclass class))
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)))
332 (call-next-method))
333
334
335 (defmethod validate-superclass ((class proxy-class) (super standard-class))
336 (subtypep (class-name super) 'proxy))
337
338 (defmethod proxy-instance-size (class)
339 (declare (ignore class))
340 0)
341 )
342
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)))
359
360 (defmethod to-alien-form (instance (class proxy-class) &rest args)
361 (declare (ignore class args))
362 `(proxy-location ,instance))
363
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)))))
375
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))))
380
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))
401
402
403 ;;;; Superclasses for wrapping of C structures
404
405 (defclass struct (proxy)
406 ()
407 (:metaclass proxy-class))
408
409 (defmethod initialize-instance ((struct struct) &rest initargs)
410 (declare (ignore initargs))
411 (unless (slot-boundp struct 'location)
412 (let ((size (proxy-instance-size (class-of struct))))
413 (if (zerop size)
414 (error "~A has zero size" (class-of struct))
415 (setf (slot-value struct 'location) (allocate-memory size)))))
416 (call-next-method))
417
418
419 ;;;; Metaclasses used for subclasses of struct
420
421 (defclass struct-class (proxy-class)
422 ())
423
424 (defmethod reference-foreign ((class struct-class) location)
425 (copy-memory location (proxy-instance-size class)))
426
427 (defmethod unreference-foreign ((class struct-class) location)
428 (deallocate-memory location))
429
430 (defmethod reader-function ((class struct-class) &rest args)
431 (declare (ignore args))
432 #'(lambda (location &optional (offset 0))
433 (let ((instance (sap-ref-sap location offset)))
434 (unless (null-pointer-p instance)
435 (ensure-proxy-instance class (reference-foreign class instance))))))
436
437
438 (defclass static-struct-class (struct-class)
439 ())
440
441 (defmethod reference-foreign ((class static-struct-class) location)
442 (declare (ignore class))
443 location)
444
445 (defmethod unreference-foreign ((class static-struct-class) location)
446 (declare (ignore class location))
447 nil)