Replace the `init' class-slot function with an `init' message.
[sod] / src / builtin.lisp
1 ;;; -*-lisp-*-
2 ;;;
3 ;;; Builtin module provides the root of the class graph
4 ;;;
5 ;;; (c) 2009 Straylight/Edgeware
6 ;;;
7
8 ;;;----- Licensing notice ---------------------------------------------------
9 ;;;
10 ;;; This file is part of the Sensible Object Design, an object system for C.
11 ;;;
12 ;;; SOD is free software; you can redistribute it and/or modify
13 ;;; it under the terms of the GNU General Public License as published by
14 ;;; the Free Software Foundation; either version 2 of the License, or
15 ;;; (at your option) any later version.
16 ;;;
17 ;;; SOD is distributed in the hope that it will be useful,
18 ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
19 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 ;;; GNU General Public License for more details.
21 ;;;
22 ;;; You should have received a copy of the GNU General Public License
23 ;;; along with SOD; if not, write to the Free Software Foundation,
24 ;;; Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25
26 (cl:in-package #:sod)
27
28 ;;;--------------------------------------------------------------------------
29 ;;; Infrastructure.
30
31 (defvar *class-slot-alist* nil)
32
33 (defun add-class-slot-function (name function)
34 "Attach a slot function to the `*class-slot-alist*'.
35
36 The FUNCTION is invoked with one argument, which is a `sod-class' object
37 to which it should add a slot. If a function with the same NAME is
38 already defined then that function is replaced; otherwise a new name/
39 function pair is defined.
40
41 Functions are are invoked in the order in which their names were first
42 added."
43
44 (aif (assoc name *class-slot-alist* :test #'string=)
45 (setf (cdr it) function)
46 (asetf *class-slot-alist* (append it (list (cons name function))))))
47
48 (defmacro define-class-slot
49 (name (class &optional stream) type init &body prepare)
50 "Define a new class slot.
51
52 The slot will be called NAME (a string) and will be of TYPE (which should
53 be a type S-expression). The slot's (static) initializer will be
54 constructed by printing the value of INIT, which is evaluated with CLASS
55 bound to the class object being constructed. If any PREPARE forms are
56 provided, then they are evaluated as a progn, with CLASS bound to the
57 class object, and STREAM bound to the output stream it should write on."
58
59 (with-gensyms (classvar)
60 `(add-class-slot-function
61 ',name
62 (lambda (,classvar)
63 (make-sod-slot ,classvar ,name (c-type ,type)
64 (make-property-set :slot-class 'sod-class-slot
65 :initializer-function
66 (lambda (,class)
67 ,init)
68 ,@(and prepare
69 `(:prepare-function
70 (lambda (,class ,stream)
71 ,@prepare)))))))))
72
73 ;;;--------------------------------------------------------------------------
74 ;;; Basic information.
75
76 (define-class-slot "name" (class) const-string
77 (prin1-to-string (sod-class-name class)))
78
79 (define-class-slot "nick" (class) const-string
80 (prin1-to-string (sod-class-nickname class)))
81
82 ;;;--------------------------------------------------------------------------
83 ;;; Instance allocation and initialization.
84
85 (define-class-slot "initsz" (class) size-t
86 (format nil "sizeof(struct ~A)" (ilayout-struct-tag class)))
87
88 (define-class-slot "imprint" (class stream)
89 (* (fun (* void) ("/*p*/" (* void))))
90 (format nil "~A__imprint" class)
91 (let ((ilayout (sod-class-ilayout class)))
92 (format stream "~&~:
93 /* Imprint raw memory with class `~A' instance structure. */
94 static void *~:*~A__imprint(void *p)
95 {
96 struct ~A *sod__obj = p;
97
98 ~:{sod__obj->~A.~A._vt = &~A.~A;~:^~% ~}
99 return (p);
100 }~2%"
101 class
102 (ilayout-struct-tag class)
103 (mapcar (lambda (ichain)
104 (let* ((head (ichain-head ichain))
105 (tail (ichain-tail ichain)))
106 (list (sod-class-nickname head)
107 (sod-class-nickname tail)
108 (vtable-name class head)
109 (sod-class-nickname tail))))
110 (ilayout-ichains ilayout)))))
111
112 ;;;--------------------------------------------------------------------------
113 ;;; Superclass structure.
114
115 (define-class-slot "n_supers" (class) size-t
116 (length (sod-class-direct-superclasses class)))
117
118 (define-class-slot "supers" (class stream)
119 (* (* (class "SodClass" :const) :const))
120 (if (null (sod-class-direct-superclasses class)) 0
121 (format nil "~A__supers" class))
122 (let ((supers (sod-class-direct-superclasses class)))
123 (when supers
124 (format stream "~&~:
125 /* Direct superclasses. */
126 static const SodClass *const ~A__supers[] = {
127 ~{~A__class~^,~% ~}
128 };~2%"
129 class supers))))
130
131 (define-class-slot "n_cpl" (class) size-t
132 (length (sod-class-precedence-list class)))
133
134 (define-class-slot "cpl" (class stream)
135 (* (* (class "SodClass" :const) :const))
136 (format nil "~A__cpl" class)
137 (format stream "~&~:
138 /* Class precedence list. */
139 static const SodClass *const ~A__cpl[] = {
140 ~{~A__class~^,~% ~}
141 };~2%"
142 class (sod-class-precedence-list class)))
143
144 ;;;--------------------------------------------------------------------------
145 ;;; Chain structure.
146
147 (define-class-slot "link" (class) (* (class "SodClass" :const))
148 (aif (sod-class-chain-link class)
149 (format nil "~A__class" it)
150 0))
151
152 (define-class-slot "head" (class) (* (class "SodClass" :const))
153 (format nil "~A__class" (sod-class-chain-head class)))
154
155 (define-class-slot "level" (class) size-t
156 (position class (reverse (sod-class-chain class))))
157
158 (define-class-slot "n_chains" (class) size-t
159 (length (sod-class-chains class)))
160
161 (define-class-slot "chains" (class stream) (* (struct "sod_chain" :const))
162 (format nil "~A__chains" class)
163 (let ((chains (sod-class-chains class)))
164 (format stream "~&~:
165 /* Chain structure. */
166 ~1@*~:{static const SodClass *const ~A__chain_~A[] = {
167 ~{~A__class~^,~% ~}
168 };~:^~2%~}
169
170 ~0@*static const struct sod_chain ~A__chains[] = {
171 ~:{ { ~
172 /* n_classes = */ ~3@*~A,
173 /* classes = */ ~0@*~A__chain_~A,
174 /* off_ichain = */ ~4@*offsetof(struct ~A, ~A),
175 /* vt = */ (const struct sod_vtable *)&~A,
176 /* ichainsz = */ sizeof(struct ~A) }~:^,~%~}
177 };~2%"
178 class ;0
179 (mapcar (lambda (chain) ;1
180 (let* ((head (sod-class-chain-head (car chain)))
181 (chain-nick (sod-class-nickname head)))
182 (list class chain-nick ;0 1
183 (reverse chain) ;2
184 (length chain) ;3
185 (ilayout-struct-tag class) chain-nick ;4 5
186 (vtable-name class head) ;6
187 (ichain-struct-tag (car chain) head)))) ;7
188 chains))))
189
190 ;;;--------------------------------------------------------------------------
191 ;;; Class-specific layout.
192
193 (define-class-slot "off_islots" (class) size-t
194 (if (sod-class-slots class)
195 (format nil "offsetof(struct ~A, ~A)"
196 (ichain-struct-tag class (sod-class-chain-head class))
197 (sod-class-nickname class))
198 "0"))
199
200 (define-class-slot "islotsz" (class) size-t
201 (if (sod-class-slots class)
202 (format nil "sizeof(struct ~A)"
203 (islots-struct-tag class))
204 "0"))
205
206 ;;;--------------------------------------------------------------------------
207 ;;; Built-in methods.
208
209 ;; Common protocol.
210
211 (defclass lifecycle-message (standard-message)
212 ())
213
214 (defclass lifecycle-effective-method (standard-effective-method)
215 ())
216
217 (defmethod effective-method-live-p ((method lifecycle-effective-method))
218 t)
219
220 (defgeneric lifecycle-method-kernel (method codegen target)
221 (:documentation
222 "Compute (into CODEGEN) the class-specific part of the METHOD.
223
224 The result, if any, needs to find its way to the TARGET, as usual."))
225
226 (defmethod simple-method-body
227 ((method lifecycle-effective-method) codegen target)
228 (invoke-delegation-chain codegen target
229 (effective-method-basic-argument-names method)
230 (effective-method-primary-methods method)
231 (lambda (target)
232 (lifecycle-method-kernel method
233 codegen
234 target))))
235
236 ;; Initialization.
237
238 (defclass initialization-message (lifecycle-message)
239 ())
240
241 (defclass initialization-effective-method (lifecycle-effective-method)
242 ())
243
244 (defmethod sod-message-effective-method-class
245 ((message initialization-message))
246 'initialization-effective-method)
247
248 (defmethod lifecycle-method-kernel
249 ((method initialization-effective-method) codegen target)
250 (let* ((class (effective-method-class method))
251 (ilayout (sod-class-ilayout class))
252 (obj-tag (ilayout-struct-tag class))
253 (func-type (c-type (fun void ("sod__obj" (* (struct obj-tag))))))
254 (func-name (format nil "~A__init" class)))
255
256 ;; Start building the initialization function.
257 (codegen-push codegen)
258
259 (labels ((set-from-initializer (var type init)
260 ;; Store the value of INIT, which has the given TYPE, in VAR.
261 ;; INIT has the syntax of an initializer: declare and
262 ;; initialize a temporary, and then copy the result.
263 ;; Compilers seem to optimize this properly. Return the
264 ;; resulting code as an instruction.
265 (codegen-push codegen)
266 (emit-decl codegen (make-var-inst *sod-tmp-val* type init))
267 (deliver-expr codegen var *sod-tmp-val*)
268 (codegen-pop-block codegen)))
269
270 ;; Loop over the instance layout emitting initializers as we find them.
271 (dolist (ichain (ilayout-ichains ilayout))
272 (let ((ich (format nil "sod__obj->~A.~A"
273 (sod-class-nickname (ichain-head ichain))
274 (sod-class-nickname (ichain-tail ichain)))))
275 (dolist (item (ichain-body ichain))
276 (etypecase item
277 (vtable-pointer
278 nil)
279 (islots
280 (let ((isl (format nil "~A.~A"
281 ich
282 (sod-class-nickname (islots-class item)))))
283 (dolist (slot (islots-slots item))
284 (let ((dslot (effective-slot-direct-slot slot))
285 (init (effective-slot-initializer slot)))
286 (when init
287 (let* ((slot-type (sod-slot-type dslot))
288 (slot-default (sod-initializer-value init))
289 (target (format nil "~A.~A"
290 isl (sod-slot-name dslot)))
291 (initinst (set-from-initializer target
292 slot-type
293 slot-default)))
294 (emit-inst codegen initinst))))))))))))
295
296 ;; Done making the initialization function.
297 (codegen-pop-function codegen func-name func-type
298 "Instance initialization function ~:_~
299 for class `~A'."
300 class)
301
302 (deliver-call codegen :void func-name "sod__obj")))
303
304 ;;;--------------------------------------------------------------------------
305 ;;; Bootstrapping the class graph.
306
307 (defun bootstrap-classes (module)
308 "Bootstrap the braid in MODULE.
309
310 This builds the fundamental recursive braid, where `SodObject' is an
311 instance of `SodClass', and `SodClass' is a subclass of `SodObject' (and
312 an instance of itself)."
313 (let* ((sod-object (make-sod-class "SodObject" nil
314 (make-property-set :nick 'obj)))
315 (sod-class (make-sod-class "SodClass" (list sod-object)
316 (make-property-set :nick 'cls)))
317 (classes (list sod-object sod-class)))
318
319 ;; Attach the built-in messages.
320 (make-sod-message sod-object "init"
321 (c-type (fun void :keys))
322 (make-property-set
323 :message-class 'initialization-message))
324
325 ;; Sort out the recursion.
326 (setf (slot-value sod-class 'chain-link) sod-object)
327 (dolist (class classes)
328 (setf (slot-value class 'metaclass) sod-class))
329
330 ;; Predeclare the class types.
331 (dolist (class classes)
332 (make-class-type (sod-class-name class)))
333
334 ;; Attach the class slots.
335 (dolist (slot *class-slot-alist*)
336 (funcall (cdr slot) sod-class))
337
338 ;; These classes are too closely intertwined. We must partially finalize
339 ;; them together by hand. This is cloned from `finalize-sod-class'.
340 (dolist (class classes)
341 (with-slots (class-precedence-list chain-head chain chains) class
342 (setf class-precedence-list (compute-cpl class))
343 (setf (values chain-head chain chains) (compute-chains class))))
344
345 ;; Done.
346 (dolist (class classes)
347 (finalize-sod-class class)
348 (add-to-module module class))))
349
350 (export '*builtin-module*)
351 (defvar *builtin-module* nil
352 "The builtin module.")
353
354 (export 'make-builtin-module)
355 (defun make-builtin-module ()
356 "Construct the builtin module.
357
358 This involves constructing the braid (which is done in
359 `bootstrap-classes') and defining a few obvious type names which users
360 will find handy.
361
362 Returns the newly constructed module, and stores it in the variable
363 `*builtin-module*'."
364 (let ((module (make-instance 'module
365 :name (make-pathname :name "SOD-BASE"
366 :type "SOD"
367 :case :common)
368 :state nil)))
369 (with-module-environment (module)
370 (dolist (name '("va_list" "size_t" "ptrdiff_t" "wchar_t"))
371 (add-to-module module (make-instance 'type-item :name name)))
372 (flet ((header-name (name)
373 (concatenate 'string "\"" (string-downcase name) ".h\""))
374 (add-includes (reason &rest names)
375 (let ((text (with-output-to-string (out)
376 (dolist (name names)
377 (format out "#include ~A~%" name)))))
378 (add-to-module module
379 (make-instance 'code-fragment-item
380 :reason reason
381 :constraints nil
382 :name :includes
383 :fragment text)))))
384 (add-includes :c (header-name "sod"))
385 (add-includes :h "<stddef.h>"))
386 (bootstrap-classes module))
387 (setf *builtin-module* module)))
388
389 (define-clear-the-decks builtin-module
390 (unless *builtin-module* (make-builtin-module)))
391
392 ;;;----- That's all, folks --------------------------------------------------