1 ;;;; -*- Mode: lisp; indent-tabs-mode: nil -*-
3 ;;; types.lisp --- User-defined CFFI types.
5 ;;; Copyright (C) 2005-2006, James Bielman <jamesjb@jamesjb.com>
6 ;;; Copyright (C) 2005-2007, Luis Oliveira <loliveira@common-lisp.net>
8 ;;; Permission is hereby granted, free of charge, to any person
9 ;;; obtaining a copy of this software and associated documentation
10 ;;; files (the "Software"), to deal in the Software without
11 ;;; restriction, including without limitation the rights to use, copy,
12 ;;; modify, merge, publish, distribute, sublicense, and/or sell copies
13 ;;; of the Software, and to permit persons to whom the Software is
14 ;;; furnished to do so, subject to the following conditions:
16 ;;; The above copyright notice and this permission notice shall be
17 ;;; included in all copies or substantial portions of the Software.
19 ;;; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
20 ;;; EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
21 ;;; MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
22 ;;; NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
23 ;;; HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
24 ;;; WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
25 ;;; OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
26 ;;; DEALINGS IN THE SOFTWARE.
33 ;; NOTE: In the C standard there's a "signed-char":
34 ;; https://stackoverflow.com/questions/436513/char-signed-char-char-unsigned-char
35 ;; and "char" may be either signed or unsigned, i.e. treating it as a small int
36 ;; is not wise. At the level of CFFI we can safely ignore this and assume that
37 ;; :char is mapped to "signed-char" by the CL implementation under us.
38 (define-built-in-foreign-type :char
)
39 (define-built-in-foreign-type :unsigned-char
)
40 (define-built-in-foreign-type :short
)
41 (define-built-in-foreign-type :unsigned-short
)
42 (define-built-in-foreign-type :int
)
43 (define-built-in-foreign-type :unsigned-int
)
44 (define-built-in-foreign-type :long
)
45 (define-built-in-foreign-type :unsigned-long
)
46 (define-built-in-foreign-type :float
)
47 (define-built-in-foreign-type :double
)
48 (define-built-in-foreign-type :void
)
50 #-cffi-sys
::no-long-long
52 (define-built-in-foreign-type :long-long
)
53 (define-built-in-foreign-type :unsigned-long-long
))
55 ;;; Define emulated LONG-LONG types. Needs checking whether we're
56 ;;; using the right sizes on various platforms.
58 ;;; A possibly better, certainly faster though more intrusive,
59 ;;; alternative is available here:
60 ;;; <http://article.gmane.org/gmane.lisp.cffi.devel/1091>
61 #+cffi-sys
::no-long-long
62 (eval-when (:compile-toplevel
:load-toplevel
:execute
)
63 (defclass emulated-llong-type
(foreign-type) ())
64 (defmethod foreign-type-size ((tp emulated-llong-type
)) 8)
65 (defmethod foreign-type-alignment ((tp emulated-llong-type
))
66 ;; better than assuming that the alignment is 8
67 (foreign-type-alignment :long
))
68 (defmethod aggregatep ((tp emulated-llong-type
)) nil
)
70 (define-foreign-type emulated-llong
(emulated-llong-type)
72 (:simple-parser
:long-long
))
74 (define-foreign-type emulated-ullong
(emulated-llong-type)
76 (:simple-parser
:unsigned-long-long
))
78 (defmethod canonicalize ((tp emulated-llong
)) :long-long
)
79 (defmethod unparse-type ((tp emulated-llong
)) :long-long
)
80 (defmethod canonicalize ((tp emulated-ullong
)) :unsigned-long-long
)
81 (defmethod unparse-type ((tp emulated-ullong
)) :unsigned-long-long
)
83 (defun %emulated-mem-ref-64
(ptr type offset
)
84 (let ((value #+big-endian
85 (+ (ash (mem-ref ptr
:unsigned-long offset
) 32)
86 (mem-ref ptr
:unsigned-long
(+ offset
4)))
88 (+ (mem-ref ptr
:unsigned-long offset
)
89 (ash (mem-ref ptr
:unsigned-long
(+ offset
4)) 32))))
90 (if (and (eq type
:long-long
) (logbitp 63 value
))
91 (lognot (logxor value
#xFFFFFFFFFFFFFFFF
))
94 (defun %emulated-mem-set-64
(value ptr type offset
)
95 (when (and (eq type
:long-long
) (minusp value
))
96 (setq value
(lognot (logxor value
#xFFFFFFFFFFFFFFFF
))))
97 (%mem-set
(ldb (byte 32 0) value
) ptr
:unsigned-long
98 #+big-endian
(+ offset
4) #+little-endian offset
)
99 (%mem-set
(ldb (byte 32 32) value
) ptr
:unsigned-long
100 #+big-endian offset
#+little-endian
(+ offset
4))
103 ;;; When some lisp other than SCL supports :long-double we should
104 ;;; use #-cffi-sys::no-long-double here instead.
105 #+(and scl long-float
) (define-built-in-foreign-type :long-double
)
107 (defparameter *possible-float-types
* '(:float
:double
:long-double
))
109 (defparameter *other-builtin-types
* '(:pointer
:void
)
110 "List of types other than integer or float built in to CFFI.")
112 (defparameter *built-in-integer-types
*
114 cffi
:*built-in-foreign-types
*
115 (append *possible-float-types
* *other-builtin-types
*))
116 "List of integer types supported by CFFI.")
118 (defparameter *built-in-float-types
*
120 cffi
:*built-in-foreign-types
*
121 (append *built-in-integer-types
* *other-builtin-types
*))
122 "List of real float types supported by CFFI.")
124 ;;;# Foreign Pointers
126 (define-modify-macro incf-pointer
(&optional
(offset 1)) inc-pointer
)
128 (defun mem-ref (ptr type
&optional
(offset 0))
129 "Return the value of TYPE at OFFSET bytes from PTR. If TYPE is aggregate,
130 we don't return its 'value' but a pointer to it, which is PTR itself."
131 (let* ((parsed-type (parse-type type
))
132 (ctype (canonicalize parsed-type
)))
133 #+cffi-sys
::no-long-long
134 (when (member ctype
'(:long-long
:unsigned-long-long
))
136 (translate-from-foreign (%emulated-mem-ref-64 ptr ctype offset
)
139 (if (aggregatep parsed-type
)
140 (if (bare-struct-type-p parsed-type
)
141 (inc-pointer ptr offset
)
142 (translate-from-foreign (inc-pointer ptr offset
) parsed-type
))
143 (translate-from-foreign (%mem-ref ptr ctype offset
) parsed-type
))))
145 (define-compiler-macro mem-ref
(&whole form ptr type
&optional
(offset 0))
146 "Compiler macro to open-code MEM-REF when TYPE is constant."
148 (let* ((parsed-type (parse-type (eval type
)))
149 (ctype (canonicalize parsed-type
)))
150 ;; Bail out when using emulated long long types.
151 #+cffi-sys
::no-long-long
152 (when (member ctype
'(:long-long
:unsigned-long-long
))
153 (return-from mem-ref form
))
154 (if (aggregatep parsed-type
)
155 (if (bare-struct-type-p parsed-type
)
156 `(inc-pointer ,ptr
,offset
)
157 (expand-from-foreign `(inc-pointer ,ptr
,offset
) parsed-type
))
158 (expand-from-foreign `(%mem-ref
,ptr
,ctype
,offset
) parsed-type
)))
161 (defun mem-set (value ptr type
&optional
(offset 0))
162 "Set the value of TYPE at OFFSET bytes from PTR to VALUE."
163 (let* ((ptype (parse-type type
))
164 (ctype (canonicalize ptype
)))
165 #+cffi-sys
::no-long-long
166 (when (or (eq ctype
:long-long
) (eq ctype
:unsigned-long-long
))
168 (%emulated-mem-set-64
(translate-to-foreign value ptype
)
170 (if (aggregatep ptype
) ; XXX: backwards incompatible?
171 (translate-into-foreign-memory value ptype
(inc-pointer ptr offset
))
172 (%mem-set
(translate-to-foreign value ptype
) ptr ctype offset
))))
174 (define-setf-expander mem-ref
(ptr type
&optional
(offset 0) &environment env
)
175 "SETF expander for MEM-REF that doesn't rebind TYPE.
176 This is necessary for the compiler macro on MEM-SET to be able
177 to open-code (SETF MEM-REF) forms."
178 (multiple-value-bind (dummies vals newval setter getter
)
179 (get-setf-expansion ptr env
)
180 (declare (ignore setter newval
))
181 ;; if either TYPE or OFFSET are constant, we avoid rebinding them
182 ;; so that the compiler macros on MEM-SET and %MEM-SET work.
183 (with-unique-names (store type-tmp offset-tmp
)
185 (append (unless (constantp type
) (list type-tmp
))
186 (unless (constantp offset
) (list offset-tmp
))
188 (append (unless (constantp type
) (list type
))
189 (unless (constantp offset
) (list offset
))
193 (mem-set ,store
,getter
194 ,@(if (constantp type
) (list type
) (list type-tmp
))
195 ,@(if (constantp offset
) (list offset
) (list offset-tmp
)))
198 ,@(if (constantp type
) (list type
) (list type-tmp
))
199 ,@(if (constantp offset
) (list offset
) (list offset-tmp
)))))))
201 (define-compiler-macro mem-set
202 (&whole form value ptr type
&optional
(offset 0))
203 "Compiler macro to open-code (SETF MEM-REF) when type is constant."
205 (let* ((parsed-type (parse-type (eval type
)))
206 (ctype (canonicalize parsed-type
)))
207 ;; Bail out when using emulated long long types.
208 #+cffi-sys
::no-long-long
209 (when (member ctype
'(:long-long
:unsigned-long-long
))
210 (return-from mem-set form
))
211 (if (aggregatep parsed-type
)
212 (expand-into-foreign-memory
213 value parsed-type
`(inc-pointer ,ptr
,offset
))
214 `(%mem-set
,(expand-to-foreign value parsed-type
)
215 ,ptr
,ctype
,offset
)))
218 ;;;# Dereferencing Foreign Arrays
220 ;;; Maybe this should be named MEM-SVREF? [2007-02-28 LO]
221 (defun mem-aref (ptr type
&optional
(index 0))
222 "Like MEM-REF except for accessing 1d arrays."
223 (mem-ref ptr type
(* index
(foreign-type-size type
))))
225 (define-compiler-macro mem-aref
(&whole form ptr type
&optional
(index 0))
226 "Compiler macro to open-code MEM-AREF when TYPE (and eventually INDEX)."
228 (if (constantp index
)
230 ,(* (eval index
) (foreign-type-size (eval type
))))
231 `(mem-ref ,ptr
,type
(* ,index
,(foreign-type-size (eval type
)))))
234 (define-setf-expander mem-aref
(ptr type
&optional
(index 0) &environment env
)
235 "SETF expander for MEM-AREF."
236 (multiple-value-bind (dummies vals newval setter getter
)
237 (get-setf-expansion ptr env
)
238 (declare (ignore setter newval
))
239 ;; we avoid rebinding type and index, if possible (and if type is not
240 ;; constant, we don't bother about the index), so that the compiler macros
241 ;; on MEM-SET or %MEM-SET can work.
242 (with-unique-names (store type-tmp index-tmp
)
244 (append (unless (constantp type
)
246 (unless (and (constantp type
) (constantp index
))
249 (append (unless (constantp type
)
251 (unless (and (constantp type
) (constantp index
))
255 ;; Here we'll try to calculate the offset from the type and index,
256 ;; or if not possible at least get the type size early.
258 ,(if (constantp type
)
259 (if (constantp index
)
260 `(mem-set ,store
,getter
,type
261 ,(* (eval index
) (foreign-type-size (eval type
))))
262 `(mem-set ,store
,getter
,type
263 (* ,index-tmp
,(foreign-type-size (eval type
)))))
264 `(mem-set ,store
,getter
,type-tmp
265 (* ,index-tmp
(foreign-type-size ,type-tmp
))))
268 ,@(if (constantp type
)
271 ,@(if (and (constantp type
) (constantp index
))
273 (list index-tmp
)))))))
275 (defmethod translate-into-foreign-memory
276 (value (type foreign-pointer-type
) pointer
)
277 (setf (mem-aref pointer
:pointer
) value
))
279 (defmethod translate-into-foreign-memory
280 (value (type foreign-built-in-type
) pointer
)
281 (setf (mem-aref pointer
(unparse-type type
)) value
))
283 (defun mem-aptr (ptr type
&optional
(index 0))
284 "The pointer to the element."
285 (inc-pointer ptr
(* index
(foreign-type-size type
))))
287 (define-compiler-macro mem-aptr
(&whole form ptr type
&optional
(index 0))
288 "The pointer to the element."
289 (cond ((not (constantp type
))
291 ((not (constantp index
))
292 `(inc-pointer ,ptr
(* ,index
,(foreign-type-size (eval type
)))))
293 ((zerop (eval index
))
296 `(inc-pointer ,ptr
,(* (eval index
)
297 (foreign-type-size (eval type
)))))))
299 (define-foreign-type foreign-array-type
()
300 ((dimensions :reader dimensions
:initarg
:dimensions
)
301 (element-type :reader element-type
:initarg
:element-type
))
302 (:actual-type
:pointer
))
304 (defmethod aggregatep ((type foreign-array-type
))
307 (defmethod print-object ((type foreign-array-type
) stream
)
308 "Print a FOREIGN-ARRAY-TYPE instance to STREAM unreadably."
309 (print-unreadable-object (type stream
:type t
:identity nil
)
310 (format stream
"~S ~S" (element-type type
) (dimensions type
))))
312 (defun array-element-size (array-type)
313 (foreign-type-size (element-type array-type
)))
315 (defmethod foreign-type-size ((type foreign-array-type
))
316 (* (array-element-size type
) (reduce #'* (dimensions type
))))
318 (defmethod foreign-type-alignment ((type foreign-array-type
))
319 (foreign-type-alignment (element-type type
)))
321 (define-parse-method :array
(element-type &rest dimensions
)
322 (assert (plusp (length dimensions
)))
323 (make-instance 'foreign-array-type
324 :element-type element-type
325 :dimensions dimensions
))
327 (defun indexes-to-row-major-index (dimensions &rest subscripts
)
328 (apply #'+ (maplist (lambda (x y
)
329 (* (car x
) (apply #'* (cdr y
))))
333 (defun row-major-index-to-indexes (index dimensions
)
334 (loop with idx
= index
335 with rank
= (length dimensions
)
336 with indexes
= (make-list rank
)
337 for dim-index from
(- rank
1) downto
0 do
338 (setf (values idx
(nth dim-index indexes
))
339 (floor idx
(nth dim-index dimensions
)))
340 finally
(return indexes
)))
342 (defun foreign-alloc (type &key
(initial-element nil initial-element-p
)
343 (initial-contents nil initial-contents-p
)
344 (count 1 count-p
) null-terminated-p
)
345 "Allocate enough memory to hold COUNT objects of type TYPE. If
346 INITIAL-ELEMENT is supplied, each element of the newly allocated
347 memory is initialized with its value. If INITIAL-CONTENTS is supplied,
348 each of its elements will be used to initialize the contents of the
349 newly allocated memory."
350 (let (contents-length)
351 ;; Some error checking, etc...
352 (when (and null-terminated-p
353 (not (eq (canonicalize-foreign-type type
) :pointer
)))
354 (error "Cannot use :NULL-TERMINATED-P with non-pointer types."))
355 (when (and initial-element-p initial-contents-p
)
356 (error "Cannot specify both :INITIAL-ELEMENT and :INITIAL-CONTENTS"))
357 (when initial-contents-p
358 (setq contents-length
(length initial-contents
))
360 (assert (>= count contents-length
))
361 (setq count contents-length
)))
362 ;; Everything looks good.
363 (let ((ptr (%foreign-alloc
(* (foreign-type-size type
)
364 (if null-terminated-p
(1+ count
) count
)))))
365 (when initial-element-p
367 (setf (mem-aref ptr type i
) initial-element
)))
368 (when initial-contents-p
369 (dotimes (i contents-length
)
370 (setf (mem-aref ptr type i
) (elt initial-contents i
))))
371 (when null-terminated-p
372 (setf (mem-aref ptr
:pointer count
) (null-pointer)))
375 ;;; Simple compiler macro that kicks in when TYPE is constant and only
376 ;;; the COUNT argument is passed. (Note: hard-coding the type's size
377 ;;; into the fasl will likely break CLISP fasl cross-platform
379 (define-compiler-macro foreign-alloc
(&whole form type
&rest args
380 &key
(count 1 count-p
) &allow-other-keys
)
381 (if (or (and count-p
(<= (length args
) 2)) (null args
))
383 ((and (constantp type
) (constantp count
))
384 `(%foreign-alloc
,(* (eval count
) (foreign-type-size (eval type
)))))
386 `(%foreign-alloc
(* ,count
,(foreign-type-size (eval type
)))))
390 (defun lisp-array-to-foreign (array pointer array-type
)
391 "Copy elements from a Lisp array to POINTER."
392 (let* ((type (ensure-parsed-base-type array-type
))
393 (el-type (element-type type
))
394 (dimensions (dimensions type
)))
395 (loop with foreign-type-size
= (array-element-size type
)
396 with size
= (reduce #'* dimensions
)
397 for i from
0 below size
398 for offset
= (* i foreign-type-size
)
399 for element
= (apply #'aref array
400 (row-major-index-to-indexes i dimensions
))
401 do
(setf (mem-ref pointer el-type offset
) element
))))
403 (defun foreign-array-to-lisp (pointer array-type
)
404 "Copy elements from ptr into a Lisp array. If POINTER is a null
405 pointer, returns NIL."
406 (unless (null-pointer-p pointer
)
407 (let* ((type (ensure-parsed-base-type array-type
))
408 (el-type (element-type type
))
409 (dimensions (dimensions type
))
410 (array (make-array dimensions
)))
411 (loop with foreign-type-size
= (array-element-size type
)
412 with size
= (reduce #'* dimensions
)
413 for i from
0 below size
414 for offset
= (* i foreign-type-size
)
415 for element
= (mem-ref pointer el-type offset
)
416 do
(setf (apply #'aref array
417 (row-major-index-to-indexes i dimensions
))
421 (defun foreign-array-alloc (array array-type
)
422 "Allocate a foreign array containing the elements of lisp array.
423 The foreign array must be freed with foreign-array-free."
424 (check-type array array
)
425 (let* ((type (ensure-parsed-base-type array-type
))
426 (ptr (foreign-alloc (element-type type
)
427 :count
(reduce #'* (dimensions type
)))))
428 (lisp-array-to-foreign array ptr array-type
)
431 (defun foreign-array-free (ptr)
432 "Free a foreign array allocated by foreign-array-alloc."
435 (defmacro with-foreign-array
((var lisp-array array-type
) &body body
)
436 "Bind var to a foreign array containing lisp-array elements in body."
437 (with-unique-names (type)
438 `(let ((,type
(ensure-parsed-base-type ,array-type
)))
439 (with-foreign-pointer (,var
(* (reduce #'* (dimensions ,type
))
440 (array-element-size ,type
)))
441 (lisp-array-to-foreign ,lisp-array
,var
,array-type
)
444 (defun foreign-aref (ptr array-type
&rest indexes
)
445 (let* ((type (ensure-parsed-base-type array-type
))
446 (offset (* (array-element-size type
)
447 (apply #'indexes-to-row-major-index
448 (dimensions type
) indexes
))))
449 (mem-ref ptr
(element-type type
) offset
)))
451 (defun (setf foreign-aref
) (value ptr array-type
&rest indexes
)
452 (let* ((type (ensure-parsed-base-type array-type
))
453 (offset (* (array-element-size type
)
454 (apply #'indexes-to-row-major-index
455 (dimensions type
) indexes
))))
456 (setf (mem-ref ptr
(element-type type
) offset
) value
)))
458 ;;; Automatic translations for the :ARRAY type. Notice that these
459 ;;; translators will also invoke the appropriate translators for for
460 ;;; each of the array's elements since that's the normal behaviour of
461 ;;; the FOREIGN-ARRAY-* operators, but there's a FIXME: **it doesn't
464 ;;; This used to be in a separate type but let's experiment with just
465 ;;; one type for a while. [2008-12-30 LO]
467 ;;; FIXME: those ugly invocations of UNPARSE-TYPE suggest that these
468 ;;; foreign array operators should take the type and dimention
469 ;;; arguments "unboxed". [2008-12-31 LO]
471 (defmethod translate-to-foreign (array (type foreign-array-type
))
472 (foreign-array-alloc array
(unparse-type type
)))
474 (defmethod translate-aggregate-to-foreign (ptr value
(type foreign-array-type
))
475 (lisp-array-to-foreign value ptr
(unparse-type type
)))
477 (defmethod translate-from-foreign (pointer (type foreign-array-type
))
478 (foreign-array-to-lisp pointer
(unparse-type type
)))
480 (defmethod free-translated-object (pointer (type foreign-array-type
) param
)
481 (declare (ignore param
))
482 (foreign-array-free pointer
))
484 ;;;# Foreign Structures
486 ;;;## Foreign Structure Slots
488 (defgeneric foreign-struct-slot-pointer
(ptr slot
)
490 "Get the address of SLOT relative to PTR."))
492 (defgeneric foreign-struct-slot-pointer-form
(ptr slot
)
494 "Return a form to get the address of SLOT in PTR."))
496 (defgeneric foreign-struct-slot-value
(ptr slot
)
498 "Return the value of SLOT in structure PTR."))
500 (defgeneric (setf foreign-struct-slot-value
) (value ptr slot
)
502 "Set the value of a SLOT in structure PTR."))
504 (defgeneric foreign-struct-slot-value-form
(ptr slot
)
506 "Return a form to get the value of SLOT in struct PTR."))
508 (defgeneric foreign-struct-slot-set-form
(value ptr slot
)
510 "Return a form to set the value of SLOT in struct PTR."))
512 (defclass foreign-struct-slot
()
513 ((name :initarg
:name
:reader slot-name
)
514 (offset :initarg
:offset
:accessor slot-offset
)
515 ;; FIXME: the type should probably be parsed?
516 (type :initarg
:type
:accessor slot-type
))
517 (:documentation
"Base class for simple and aggregate slots."))
519 (defmethod foreign-struct-slot-pointer (ptr (slot foreign-struct-slot
))
520 "Return the address of SLOT relative to PTR."
521 (inc-pointer ptr
(slot-offset slot
)))
523 (defmethod foreign-struct-slot-pointer-form (ptr (slot foreign-struct-slot
))
524 "Return a form to get the address of SLOT relative to PTR."
525 (let ((offset (slot-offset slot
)))
528 `(inc-pointer ,ptr
,offset
))))
530 (defun foreign-slot-names (type)
531 "Returns a list of TYPE's slot names in no particular order."
532 (loop for value being the hash-values
533 in
(slots (ensure-parsed-base-type type
))
534 collect
(slot-name value
)))
538 (defclass simple-struct-slot
(foreign-struct-slot)
540 (:documentation
"Non-aggregate structure slots."))
542 (defmethod foreign-struct-slot-value (ptr (slot simple-struct-slot
))
543 "Return the value of a simple SLOT from a struct at PTR."
544 (mem-ref ptr
(slot-type slot
) (slot-offset slot
)))
546 (defmethod foreign-struct-slot-value-form (ptr (slot simple-struct-slot
))
547 "Return a form to get the value of a slot from PTR."
548 `(mem-ref ,ptr
',(slot-type slot
) ,(slot-offset slot
)))
550 (defmethod (setf foreign-struct-slot-value
) (value ptr
(slot simple-struct-slot
))
551 "Set the value of a simple SLOT to VALUE in PTR."
552 (setf (mem-ref ptr
(slot-type slot
) (slot-offset slot
)) value
))
554 (defmethod foreign-struct-slot-set-form (value ptr
(slot simple-struct-slot
))
555 "Return a form to set the value of a simple structure slot."
556 `(setf (mem-ref ,ptr
',(slot-type slot
) ,(slot-offset slot
)) ,value
))
558 ;;;### Aggregate Slots
560 (defclass aggregate-struct-slot
(foreign-struct-slot)
561 ((count :initarg
:count
:accessor slot-count
))
562 (:documentation
"Aggregate structure slots."))
564 ;;; Since MEM-REF returns a pointer for struct types we are able to
565 ;;; chain together slot names when accessing slot values in nested
567 (defmethod foreign-struct-slot-value (ptr (slot aggregate-struct-slot
))
568 "Return a pointer to SLOT relative to PTR."
569 (convert-from-foreign (inc-pointer ptr
(slot-offset slot
))
572 (defmethod foreign-struct-slot-value-form (ptr (slot aggregate-struct-slot
))
573 "Return a form to get the value of SLOT relative to PTR."
574 `(convert-from-foreign (inc-pointer ,ptr
,(slot-offset slot
))
577 (defmethod translate-aggregate-to-foreign (ptr value
(type foreign-struct-type
))
578 ;;; FIXME: use the block memory interface instead.
579 (loop for i below
(foreign-type-size type
)
580 do
(%mem-set
(%mem-ref value
:char i
) ptr
:char i
)))
582 (defmethod (setf foreign-struct-slot-value
)
583 (value ptr
(slot aggregate-struct-slot
))
584 "Set the value of an aggregate SLOT to VALUE in PTR."
585 (translate-aggregate-to-foreign (inc-pointer ptr
(slot-offset slot
))
587 (parse-type (slot-type slot
))))
589 (defmethod foreign-struct-slot-set-form (value ptr
(slot aggregate-struct-slot
))
590 "Return a form to get the value of an aggregate SLOT relative to PTR."
591 `(translate-aggregate-to-foreign (inc-pointer ,ptr
,(slot-offset slot
))
593 ,(parse-type (slot-type slot
))))
595 ;;;## Defining Foreign Structures
597 (defun make-struct-slot (name offset type count
)
598 "Make the appropriate type of structure slot."
599 ;; If TYPE is an aggregate type or COUNT is >1, create an
600 ;; AGGREGATE-STRUCT-SLOT, otherwise a SIMPLE-STRUCT-SLOT.
601 (if (or (> count
1) (aggregatep (parse-type type
)))
602 (make-instance 'aggregate-struct-slot
:offset offset
:type type
603 :name name
:count count
)
604 (make-instance 'simple-struct-slot
:offset offset
:type type
607 (defun parse-deprecated-struct-type (name struct-or-union
)
608 (check-type struct-or-union
(member :struct
:union
))
609 (let* ((struct-type-name `(,struct-or-union
,name
))
610 (struct-type (parse-type struct-type-name
)))
611 (simple-style-warning
612 "bare references to struct types are deprecated. ~
613 Please use ~S or ~S instead."
614 `(:pointer
,struct-type-name
) struct-type-name
)
615 (make-instance (class-of struct-type
)
616 :alignment
(alignment struct-type
)
617 :size
(size struct-type
)
618 :slots
(slots struct-type
)
619 :name
(name struct-type
)
622 ;;; Regarding structure alignment, the following ABIs were checked:
623 ;;; - System-V ABI: x86, x86-64, ppc, arm, mips and itanium. (more?)
624 ;;; - Mac OS X ABI Function Call Guide: ppc32, ppc64 and x86.
628 ;;; 1. "An entire structure or union object is aligned on the same
629 ;;; boundary as its most strictly aligned member."
631 ;;; 2. "Each member is assigned to the lowest available offset with
632 ;;; the appropriate alignment. This may require internal
633 ;;; padding, depending on the previous member."
635 ;;; 3. "A structure's size is increased, if necessary, to make it a
636 ;;; multiple of the alignment. This may require tail padding,
637 ;;; depending on the last member."
639 ;;; Special cases from darwin/ppc32's ABI:
640 ;;; http://developer.apple.com/documentation/DeveloperTools/Conceptual/LowLevelABI/index.html
642 ;;; 4. "The embedding alignment of the first element in a data
643 ;;; structure is equal to the element's natural alignment."
645 ;;; 5. "For subsequent elements that have a natural alignment
646 ;;; greater than 4 bytes, the embedding alignment is 4, unless
647 ;;; the element is a vector." (note: this applies for
650 ;; FIXME: get a better name for this. --luis
651 (defun get-alignment (type alignment-type firstp
)
652 "Return alignment for TYPE according to ALIGNMENT-TYPE."
653 (declare (ignorable firstp
))
654 (ecase alignment-type
655 (:normal
#-
(and darwin ppc
)
656 (foreign-type-alignment type
)
659 (foreign-type-alignment type
)
660 (min 4 (foreign-type-alignment type
))))))
662 (defun adjust-for-alignment (type offset alignment-type firstp
)
663 "Return OFFSET aligned properly for TYPE according to ALIGNMENT-TYPE."
664 (let* ((align (get-alignment type alignment-type firstp
))
665 (rem (mod offset align
)))
668 (+ offset
(- align rem
)))))
670 (defmacro with-tentative-type-definition
((name value namespace
) &body body
)
671 (once-only (name namespace
)
672 `(unwind-protect-case ()
674 (notice-foreign-type ,name
,value
,namespace
)
676 (:abort
(undefine-foreign-type ,name
,namespace
)))))
678 (defun notice-foreign-struct-definition (name options slots
)
679 "Parse and install a foreign structure definition."
680 (destructuring-bind (&key size
(class 'foreign-struct-type
))
682 (let ((struct (make-instance class
:name name
))
686 (with-tentative-type-definition (name struct
:struct
)
688 (dolist (slotdef slots
)
689 (destructuring-bind (slotname type
&key
(count 1) offset
) slotdef
690 (when (eq (canonicalize-foreign-type type
) :void
)
691 (simple-foreign-type-error type
:struct
692 "In struct ~S: void type not allowed in field ~S"
696 (adjust-for-alignment type current-offset
:normal firstp
)))
697 (let* ((slot (make-struct-slot slotname current-offset type count
))
698 (align (get-alignment (slot-type slot
) :normal firstp
)))
699 (setf (gethash slotname
(slots struct
)) slot
)
700 (when (> align max-align
)
701 (setq max-align align
)))
702 (incf current-offset
(* count
(foreign-type-size type
))))
704 ;; calculate padding and alignment
705 (setf (alignment struct
) max-align
) ; See point 1 above.
706 (let ((tail-padding (- max-align
(rem current-offset max-align
))))
707 (unless (= tail-padding max-align
) ; See point 3 above.
708 (incf current-offset tail-padding
)))
709 (setf (size struct
) (or size current-offset
))))))
711 (defun generate-struct-accessors (name conc-name slot-names
)
712 (loop with pointer-arg
= (symbolicate '#:pointer-to- name
)
713 for slot in slot-names
714 for accessor
= (symbolicate conc-name slot
)
715 collect
`(defun ,accessor
(,pointer-arg
)
716 (foreign-slot-value ,pointer-arg
'(:struct
,name
) ',slot
))
717 collect
`(defun (setf ,accessor
) (value ,pointer-arg
)
718 (foreign-slot-set value
,pointer-arg
'(:struct
,name
) ',slot
))))
720 (define-parse-method :struct
(name)
721 (funcall (find-type-parser name
:struct
)))
723 (defvar *defcstruct-hook
* nil
)
725 (defmacro defcstruct
(name-and-options &body fields
)
726 "Define the layout of a foreign structure."
727 (discard-docstring fields
)
728 (destructuring-bind (name . options
)
729 (ensure-list name-and-options
)
730 (let ((conc-name (getf options
:conc-name
)))
731 (remf options
:conc-name
)
732 (unless (getf options
:class
) (setf (getf options
:class
) (symbolicate name
'-tclass
)))
733 `(eval-when (:compile-toplevel
:load-toplevel
:execute
)
734 ;; m-f-s-t could do with this with mop:ensure-class.
735 ,(when-let (class (getf options
:class
))
736 `(defclass ,class
(foreign-struct-type
737 translatable-foreign-type
)
739 (notice-foreign-struct-definition ',name
',options
',fields
)
741 (generate-struct-accessors name conc-name
742 (mapcar #'car fields
)))
743 ,@(when *defcstruct-hook
*
744 ;; If non-nil, *defcstruct-hook* should be a function
745 ;; of the arguments that returns NIL or a list of
746 ;; forms to include in the expansion.
747 (apply *defcstruct-hook
* name-and-options fields
))
748 (define-parse-method ,name
()
749 (parse-deprecated-struct-type ',name
:struct
))
752 ;;;## Accessing Foreign Structure Slots
754 (defun get-slot-info (type slot-name
)
755 "Return the slot info for SLOT-NAME or raise an error."
756 (let* ((struct (ensure-parsed-base-type type
))
757 (info (gethash slot-name
(slots struct
))))
759 (simple-foreign-type-error type
:struct
760 "Undefined slot ~A in foreign type ~A."
764 (defun foreign-slot-pointer (ptr type slot-name
)
765 "Return the address of SLOT-NAME in the structure at PTR."
766 (foreign-struct-slot-pointer ptr
(get-slot-info type slot-name
)))
768 (define-compiler-macro foreign-slot-pointer
(&whole whole ptr type slot-name
)
769 (if (and (constantp type
) (constantp slot-name
))
770 (foreign-struct-slot-pointer-form
771 ptr
(get-slot-info (eval type
) (eval slot-name
)))
774 (defun foreign-slot-type (type slot-name
)
775 "Return the type of SLOT in a struct TYPE."
776 (slot-type (get-slot-info type slot-name
)))
778 (defun foreign-slot-offset (type slot-name
)
779 "Return the offset of SLOT in a struct TYPE."
780 (slot-offset (get-slot-info type slot-name
)))
782 (defun foreign-slot-count (type slot-name
)
783 "Return the number of items in SLOT in a struct TYPE."
784 (slot-count (get-slot-info type slot-name
)))
786 (defun foreign-slot-value (ptr type slot-name
)
787 "Return the value of SLOT-NAME in the foreign structure at PTR."
788 (foreign-struct-slot-value ptr
(get-slot-info type slot-name
)))
790 (define-compiler-macro foreign-slot-value
(&whole form ptr type slot-name
)
791 "Optimizer for FOREIGN-SLOT-VALUE when TYPE is constant."
792 (if (and (constantp type
) (constantp slot-name
))
793 (foreign-struct-slot-value-form
794 ptr
(get-slot-info (eval type
) (eval slot-name
)))
797 (define-setf-expander foreign-slot-value
(ptr type slot-name
&environment env
)
798 "SETF expander for FOREIGN-SLOT-VALUE."
799 (multiple-value-bind (dummies vals newval setter getter
)
800 (get-setf-expansion ptr env
)
801 (declare (ignore setter newval
))
802 (if (and (constantp type
) (constantp slot-name
))
803 ;; if TYPE and SLOT-NAME are constant we avoid rebinding them
804 ;; so that the compiler macro on FOREIGN-SLOT-SET works.
805 (with-unique-names (store)
811 (foreign-slot-set ,store
,getter
,type
,slot-name
)
813 `(foreign-slot-value ,getter
,type
,slot-name
)))
815 (with-unique-names (store slot-name-tmp type-tmp
)
817 (list* type-tmp slot-name-tmp dummies
)
818 (list* type slot-name vals
)
821 (foreign-slot-set ,store
,getter
,type-tmp
,slot-name-tmp
)
823 `(foreign-slot-value ,getter
,type-tmp
,slot-name-tmp
))))))
825 (defun foreign-slot-set (value ptr type slot-name
)
826 "Set the value of SLOT-NAME in a foreign structure."
827 (setf (foreign-struct-slot-value ptr
(get-slot-info type slot-name
)) value
))
829 (define-compiler-macro foreign-slot-set
830 (&whole form value ptr type slot-name
)
831 "Optimizer when TYPE and SLOT-NAME are constant."
832 (if (and (constantp type
) (constantp slot-name
))
833 (foreign-struct-slot-set-form
834 value ptr
(get-slot-info (eval type
) (eval slot-name
)))
837 (defmacro with-foreign-slots
((vars ptr type
) &body body
)
838 "Create local symbol macros for each var in VARS to reference
839 foreign slots in PTR of TYPE. Similar to WITH-SLOTS.
840 Each var can be of the form: slot-name - in which case slot-name will
841 be bound to the value of the slot or: (:pointer slot-name) - in which
842 case slot-name will be bound to the pointer to that slot."
843 (let ((ptr-var (gensym "PTR")))
844 `(let ((,ptr-var
,ptr
))
846 ,(loop :for var
:in vars
849 (if (eq (first var
) :pointer
)
850 `(,(second var
) (foreign-slot-pointer
851 ,ptr-var
',type
',(second var
)))
853 "Malformed slot specification ~a; must be:`name' or `(:pointer name)'"
855 `(,var
(foreign-slot-value ,ptr-var
',type
',var
))))
858 ;;; We could add an option to define a struct instead of a class, in
859 ;;; the unlikely event someone needs something like that.
860 (defmacro define-c-struct-wrapper
(class-and-type supers
&optional slots
)
861 "Define a new class with CLOS slots matching those of a foreign
862 struct type. An INITIALIZE-INSTANCE method is defined which
863 takes a :POINTER initarg that is used to store the slots of a
864 foreign object. This pointer is only used for initialization and
867 CLASS-AND-TYPE is either a list of the form (class-name
868 struct-type) or a single symbol naming both. The class will
869 inherit SUPERS. If a list of SLOTS is specified, only those
870 slots will be defined and stored."
871 (destructuring-bind (class-name &optional
(struct-type (list :struct class-name
)))
872 (ensure-list class-and-type
)
873 (let ((slots (or slots
(foreign-slot-names struct-type
))))
875 (defclass ,class-name
,supers
876 ,(loop for slot in slots collect
877 `(,slot
:reader
,(format-symbol t
"~A-~A" class-name slot
))))
878 ;; This could be done in a parent class by using
879 ;; FOREIGN-SLOT-NAMES when instantiating but then the compiler
880 ;; macros wouldn't kick in.
881 (defmethod initialize-instance :after
((inst ,class-name
) &key pointer
)
882 (with-foreign-slots (,slots pointer
,struct-type
)
883 ,@(loop for slot in slots collect
884 `(setf (slot-value inst
',slot
) ,slot
))))
889 ;;; A union is a subclass of FOREIGN-STRUCT-TYPE in which all slots
890 ;;; have an offset of zero.
892 ;;; See also the notes regarding ABI requirements in
893 ;;; NOTICE-FOREIGN-STRUCT-DEFINITION
894 (defun notice-foreign-union-definition (name-and-options slots
)
895 "Parse and install a foreign union definition."
896 (destructuring-bind (name &key size
)
897 (ensure-list name-and-options
)
898 (let ((union (make-instance 'foreign-union-type
:name name
))
901 (with-tentative-type-definition (name union
:union
)
902 (dolist (slotdef slots
)
903 (destructuring-bind (slotname type
&key
(count 1)) slotdef
904 (when (eq (canonicalize-foreign-type type
) :void
)
905 (simple-foreign-type-error name
:struct
906 "In union ~S: void type not allowed in field ~S"
908 (let* ((slot (make-struct-slot slotname
0 type count
))
909 (size (* count
(foreign-type-size type
)))
910 (align (foreign-type-alignment (slot-type slot
))))
911 (setf (gethash slotname
(slots union
)) slot
)
912 (when (> size max-size
)
913 (setf max-size size
))
914 (when (> align max-align
)
915 (setf max-align align
)))))
916 (setf (size union
) (or size max-size
))
917 (setf (alignment union
) max-align
)))))
919 (define-parse-method :union
(name)
920 (funcall (find-type-parser name
:union
)))
922 (defmacro defcunion
(name-and-options &body fields
)
923 "Define the layout of a foreign union."
924 (discard-docstring fields
)
925 (destructuring-bind (name &key size
)
926 (ensure-list name-and-options
)
927 (declare (ignore size
))
928 `(eval-when (:compile-toplevel
:load-toplevel
:execute
)
929 (notice-foreign-union-definition ',name-and-options
',fields
)
930 (define-parse-method ,name
()
931 (parse-deprecated-struct-type ',name
:union
))
934 ;;;# Operations on Types
936 (defmethod foreign-type-alignment (type)
937 "Return the alignment in bytes of a foreign type."
938 (foreign-type-alignment (parse-type type
)))
940 (defmacro with-foreign-object
((var type
&optional
(count 1)) &body body
)
941 "Bind VAR to a pointer to COUNT objects of TYPE during BODY.
942 The buffer has dynamic extent and may be stack allocated."
943 `(with-foreign-pointer
944 (,var
,(if (constantp type
)
945 ;; with-foreign-pointer may benefit from constant folding:
946 (if (constantp count
)
947 (* (eval count
) (foreign-type-size (eval type
)))
948 `(* ,count
,(foreign-type-size (eval type
))))
949 `(* ,count
(foreign-type-size ,type
))))
952 (defmacro with-foreign-objects
(bindings &body body
)
954 `(with-foreign-object ,(car bindings
)
955 (with-foreign-objects ,(cdr bindings
)
959 ;;;## Anonymous Type Translators
961 ;;; (:wrapper :to-c some-function :from-c another-function)
963 ;;; TODO: We will need to add a FREE function to this as well I think.
966 (define-foreign-type foreign-type-wrapper
()
967 ((to-c :initarg
:to-c
:reader wrapper-to-c
)
968 (from-c :initarg
:from-c
:reader wrapper-from-c
))
969 (:documentation
"Wrapper type."))
971 (define-parse-method :wrapper
(base-type &key to-c from-c
)
972 (make-instance 'foreign-type-wrapper
973 :actual-type
(parse-type base-type
)
974 :to-c
(or to-c
'identity
)
975 :from-c
(or from-c
'identity
)))
977 (defmethod translate-to-foreign (value (type foreign-type-wrapper
))
978 (translate-to-foreign
979 (funcall (slot-value type
'to-c
) value
) (actual-type type
)))
981 (defmethod translate-from-foreign (value (type foreign-type-wrapper
))
982 (funcall (slot-value type
'from-c
)
983 (translate-from-foreign value
(actual-type type
))))
987 ;;; Boolean type. Maps to an :int by default. Only accepts integer types.
988 (define-foreign-type foreign-boolean-type
()
991 (define-parse-method :boolean
(&optional
(base-type :int
))
993 'foreign-boolean-type
:actual-type
994 (ecase (canonicalize-foreign-type base-type
)
995 ((:char
:unsigned-char
:int
:unsigned-int
:long
:unsigned-long
996 #-cffi-sys
::no-long-long
:long-long
997 #-cffi-sys
::no-long-long
:unsigned-long-long
) base-type
))))
999 (defmethod translate-to-foreign (value (type foreign-boolean-type
))
1002 (defmethod translate-from-foreign (value (type foreign-boolean-type
))
1003 (not (zerop value
)))
1005 (defmethod expand-to-foreign (value (type foreign-boolean-type
))
1006 "Optimization for the :boolean type."
1007 (if (constantp value
)
1008 (if (eval value
) 1 0)
1011 (defmethod expand-from-foreign (value (type foreign-boolean-type
))
1012 "Optimization for the :boolean type."
1013 (if (constantp value
) ; very unlikely, heh
1014 (not (zerop (eval value
)))
1015 `(not (zerop ,value
))))
1017 ;;; Boolean type that represents C99 _Bool
1018 (defctype :bool
(:boolean
:char
))
1020 ;;;# Typedefs for built-in types.
1022 (defctype :uchar
:unsigned-char
)
1023 (defctype :ushort
:unsigned-short
)
1024 (defctype :uint
:unsigned-int
)
1025 (defctype :ulong
:unsigned-long
)
1026 (defctype :llong
:long-long
)
1027 (defctype :ullong
:unsigned-long-long
)
1029 ;;; We try to define the :[u]int{8,16,32,64} types by looking at
1030 ;;; the sizes of the built-in integer types and defining typedefs.
1031 (eval-when (:compile-toplevel
:load-toplevel
:execute
)
1033 ((match-types (sized-types mtypes
)
1035 ,@(loop for
(type . size-or-type
) in sized-types
1036 for m
= (car (member (if (keywordp size-or-type
)
1037 (foreign-type-size size-or-type
)
1039 mtypes
:key
#'foreign-type-size
))
1040 when m collect
`(defctype ,type
,m
)))))
1042 (match-types ((:int8 .
1) (:int16 .
2) (:int32 .
4) (:int64 .
8)
1043 (:intptr .
:pointer
))
1044 (:char
:short
:int
:long
:long-long
))
1046 (match-types ((:uint8 .
1) (:uint16 .
2) (:uint32 .
4) (:uint64 .
8)
1047 (:uintptr .
:pointer
))
1048 (:unsigned-char
:unsigned-short
:unsigned-int
:unsigned-long
1049 :unsigned-long-long
))))