-
Notifications
You must be signed in to change notification settings - Fork 0
/
jsiter.c
1080 lines (949 loc) · 32.3 KB
/
jsiter.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sw=4 et tw=78:
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Communicator client code, released
* March 31, 1998.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/*
* JavaScript iterators.
*/
#include "jsstddef.h"
#include <string.h> /* for memcpy */
#include "jstypes.h"
#include "jsutil.h"
#include "jsarena.h"
#include "jsapi.h"
#include "jsarray.h"
#include "jsatom.h"
#include "jsbool.h"
#include "jscntxt.h"
#include "jsconfig.h"
#include "jsexn.h"
#include "jsfun.h"
#include "jsgc.h"
#include "jsinterp.h"
#include "jsiter.h"
#include "jslock.h"
#include "jsnum.h"
#include "jsobj.h"
#include "jsopcode.h"
#include "jsscope.h"
#include "jsscript.h"
#if JS_HAS_XML_SUPPORT
#include "jsxml.h"
#endif
extern const char js_throw_str[]; /* from jsscan.h */
#define JSSLOT_ITER_STATE (JSSLOT_PRIVATE)
#define JSSLOT_ITER_FLAGS (JSSLOT_PRIVATE + 1)
#if JSSLOT_ITER_FLAGS >= JS_INITIAL_NSLOTS
#error JS_INITIAL_NSLOTS must be greater than JSSLOT_ITER_FLAGS.
#endif
/*
* Shared code to close iterator's state either through an explicit call or
* when GC detects that the iterator is no longer reachable.
*/
void
js_CloseIteratorState(JSContext *cx, JSObject *iterobj)
{
jsval *slots;
jsval state, parent;
JSObject *iterable;
JS_ASSERT(JS_InstanceOf(cx, iterobj, &js_IteratorClass, NULL));
slots = iterobj->slots;
/* Avoid double work if js_CloseNativeIterator was called on obj. */
state = slots[JSSLOT_ITER_STATE];
if (JSVAL_IS_NULL(state))
return;
/* Protect against failure to fully initialize obj. */
parent = slots[JSSLOT_PARENT];
if (!JSVAL_IS_PRIMITIVE(parent)) {
iterable = JSVAL_TO_OBJECT(parent);
#if JS_HAS_XML_SUPPORT
if ((JSVAL_TO_INT(slots[JSSLOT_ITER_FLAGS]) & JSITER_FOREACH) &&
OBJECT_IS_XML(cx, iterable)) {
((JSXMLObjectOps *) iterable->map->ops)->
enumerateValues(cx, iterable, JSENUMERATE_DESTROY, &state,
NULL, NULL);
} else
#endif
OBJ_ENUMERATE(cx, iterable, JSENUMERATE_DESTROY, &state, NULL);
}
slots[JSSLOT_ITER_STATE] = JSVAL_NULL;
}
JSClass js_IteratorClass = {
"Iterator",
JSCLASS_HAS_RESERVED_SLOTS(2) | /* slots for state and flags */
JSCLASS_HAS_CACHED_PROTO(JSProto_Iterator),
JS_PropertyStub, JS_PropertyStub, JS_PropertyStub, JS_PropertyStub,
JS_EnumerateStub, JS_ResolveStub, JS_ConvertStub, JS_FinalizeStub,
JSCLASS_NO_OPTIONAL_MEMBERS
};
static JSBool
InitNativeIterator(JSContext *cx, JSObject *iterobj, JSObject *obj, uintN flags)
{
jsval state;
JSBool ok;
JS_ASSERT(JSVAL_TO_PRIVATE(iterobj->slots[JSSLOT_CLASS]) ==
&js_IteratorClass);
/* Initialize iterobj in case of enumerate hook failure. */
iterobj->slots[JSSLOT_PARENT] = OBJECT_TO_JSVAL(obj);
iterobj->slots[JSSLOT_ITER_STATE] = JSVAL_NULL;
iterobj->slots[JSSLOT_ITER_FLAGS] = INT_TO_JSVAL(flags);
if (!js_RegisterCloseableIterator(cx, iterobj))
return JS_FALSE;
if (!obj)
return JS_TRUE;
ok =
#if JS_HAS_XML_SUPPORT
((flags & JSITER_FOREACH) && OBJECT_IS_XML(cx, obj))
? ((JSXMLObjectOps *) obj->map->ops)->
enumerateValues(cx, obj, JSENUMERATE_INIT, &state, NULL, NULL)
:
#endif
OBJ_ENUMERATE(cx, obj, JSENUMERATE_INIT, &state, NULL);
if (!ok)
return JS_FALSE;
iterobj->slots[JSSLOT_ITER_STATE] = state;
if (flags & JSITER_ENUMERATE) {
/*
* The enumerating iterator needs the original object to suppress
* enumeration of deleted or shadowed prototype properties. Since the
* enumerator never escapes to scripts, we use the prototype slot to
* store the original object.
*/
JS_ASSERT(obj != iterobj);
iterobj->slots[JSSLOT_PROTO] = OBJECT_TO_JSVAL(obj);
}
return JS_TRUE;
}
static JSBool
Iterator(JSContext *cx, JSObject *iterobj, uintN argc, jsval *argv, jsval *rval)
{
JSBool keyonly;
uintN flags;
JSObject *obj;
keyonly = JS_FALSE;
if (!js_ValueToBoolean(cx, argv[1], &keyonly))
return JS_FALSE;
flags = keyonly ? 0 : JSITER_FOREACH;
if (cx->fp->flags & JSFRAME_CONSTRUCTING) {
/* XXX work around old valueOf call hidden beneath js_ValueToObject */
if (!JSVAL_IS_PRIMITIVE(argv[0])) {
obj = JSVAL_TO_OBJECT(argv[0]);
} else {
obj = js_ValueToNonNullObject(cx, argv[0]);
if (!obj)
return JS_FALSE;
argv[0] = OBJECT_TO_JSVAL(obj);
}
return InitNativeIterator(cx, iterobj, obj, flags);
}
*rval = argv[0];
return js_ValueToIterator(cx, flags, rval);
}
static JSBool
NewKeyValuePair(JSContext *cx, jsid key, jsval val, jsval *rval)
{
jsval vec[2];
JSTempValueRooter tvr;
JSObject *aobj;
vec[0] = ID_TO_VALUE(key);
vec[1] = val;
JS_PUSH_TEMP_ROOT(cx, 2, vec, &tvr);
aobj = js_NewArrayObject(cx, 2, vec);
*rval = OBJECT_TO_JSVAL(aobj);
JS_POP_TEMP_ROOT(cx, &tvr);
return aobj != NULL;
}
static JSBool
IteratorNextImpl(JSContext *cx, JSObject *obj, jsval *rval)
{
JSObject *iterable;
jsval state;
uintN flags;
JSBool foreach, ok;
jsid id;
JS_ASSERT(OBJ_GET_CLASS(cx, obj) == &js_IteratorClass);
iterable = OBJ_GET_PARENT(cx, obj);
JS_ASSERT(iterable);
state = OBJ_GET_SLOT(cx, obj, JSSLOT_ITER_STATE);
if (JSVAL_IS_NULL(state))
goto stop;
flags = JSVAL_TO_INT(OBJ_GET_SLOT(cx, obj, JSSLOT_ITER_FLAGS));
JS_ASSERT(!(flags & JSITER_ENUMERATE));
foreach = (flags & JSITER_FOREACH) != 0;
ok =
#if JS_HAS_XML_SUPPORT
(foreach && OBJECT_IS_XML(cx, iterable))
? ((JSXMLObjectOps *) iterable->map->ops)->
enumerateValues(cx, iterable, JSENUMERATE_NEXT, &state,
&id, rval)
:
#endif
OBJ_ENUMERATE(cx, iterable, JSENUMERATE_NEXT, &state, &id);
if (!ok)
return JS_FALSE;
OBJ_SET_SLOT(cx, obj, JSSLOT_ITER_STATE, state);
if (JSVAL_IS_NULL(state))
goto stop;
if (foreach) {
#if JS_HAS_XML_SUPPORT
if (!OBJECT_IS_XML(cx, iterable) &&
!OBJ_GET_PROPERTY(cx, iterable, id, rval)) {
return JS_FALSE;
}
#endif
if (!NewKeyValuePair(cx, id, *rval, rval))
return JS_FALSE;
} else {
*rval = ID_TO_VALUE(id);
}
return JS_TRUE;
stop:
JS_ASSERT(OBJ_GET_SLOT(cx, obj, JSSLOT_ITER_STATE) == JSVAL_NULL);
*rval = JSVAL_HOLE;
return JS_TRUE;
}
static JSBool
js_ThrowStopIteration(JSContext *cx, JSObject *obj)
{
jsval v;
JS_ASSERT(!JS_IsExceptionPending(cx));
if (js_FindClassObject(cx, NULL, INT_TO_JSID(JSProto_StopIteration), &v))
JS_SetPendingException(cx, v);
return JS_FALSE;
}
static JSBool
iterator_next(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
jsval *rval)
{
if (!JS_InstanceOf(cx, obj, &js_IteratorClass, argv))
return JS_FALSE;
if (!IteratorNextImpl(cx, obj, rval))
return JS_FALSE;
if (*rval == JSVAL_HOLE) {
*rval = JSVAL_NULL;
js_ThrowStopIteration(cx, obj);
return JS_FALSE;
}
return JS_TRUE;
}
static JSBool
iterator_self(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
jsval *rval)
{
*rval = OBJECT_TO_JSVAL(obj);
return JS_TRUE;
}
static JSFunctionSpec iterator_methods[] = {
{js_iterator_str, iterator_self, 0,JSPROP_READONLY|JSPROP_PERMANENT,0},
{js_next_str, iterator_next, 0,JSPROP_READONLY|JSPROP_PERMANENT,0},
{0,0,0,0,0}
};
uintN
js_GetNativeIteratorFlags(JSContext *cx, JSObject *iterobj)
{
if (OBJ_GET_CLASS(cx, iterobj) != &js_IteratorClass)
return 0;
return JSVAL_TO_INT(OBJ_GET_SLOT(cx, iterobj, JSSLOT_ITER_FLAGS));
}
void
js_CloseNativeIterator(JSContext *cx, JSObject *iterobj)
{
uintN flags;
/*
* If this iterator is not an instance of the native default iterator
* class, leave it to be GC'ed.
*/
if (!JS_InstanceOf(cx, iterobj, &js_IteratorClass, NULL))
return;
/*
* If this iterator was not created by js_ValueToIterator called from the
* for-in loop code in js_Interpret, leave it to be GC'ed.
*/
flags = JSVAL_TO_INT(OBJ_GET_SLOT(cx, iterobj, JSSLOT_ITER_FLAGS));
if (!(flags & JSITER_ENUMERATE))
return;
js_CloseIteratorState(cx, iterobj);
}
/*
* Call ToObject(v).__iterator__(keyonly) if ToObject(v).__iterator__ exists.
* Otherwise construct the defualt iterator.
*/
JSBool
js_ValueToIterator(JSContext *cx, uintN flags, jsval *vp)
{
JSObject *obj;
JSTempValueRooter tvr;
const JSAtom *atom;
JSBool ok;
JSObject *iterobj;
jsval arg;
JSString *str;
JS_ASSERT(!(flags & ~(JSITER_ENUMERATE |
JSITER_FOREACH |
JSITER_KEYVALUE)));
/* JSITER_KEYVALUE must always come with JSITER_FOREACH */
JS_ASSERT(!(flags & JSITER_KEYVALUE) || (flags & JSITER_FOREACH));
/* XXX work around old valueOf call hidden beneath js_ValueToObject */
if (!JSVAL_IS_PRIMITIVE(*vp)) {
obj = JSVAL_TO_OBJECT(*vp);
} else {
/*
* Enumerating over null and undefined gives an empty enumerator.
* This is contrary to ECMA-262 9.9 ToObject, invoked from step 3 of
* the first production in 12.6.4 and step 4 of the second production,
* but it's "web JS" compatible.
*/
if ((flags & JSITER_ENUMERATE)) {
if (!js_ValueToObject(cx, *vp, &obj))
return JS_FALSE;
if (!obj)
goto default_iter;
} else {
obj = js_ValueToNonNullObject(cx, *vp);
if (!obj)
return JS_FALSE;
}
}
JS_ASSERT(obj);
JS_PUSH_TEMP_ROOT_OBJECT(cx, obj, &tvr);
atom = cx->runtime->atomState.iteratorAtom;
#if JS_HAS_XML_SUPPORT
if (OBJECT_IS_XML(cx, obj)) {
if (!js_GetXMLFunction(cx, obj, ATOM_TO_JSID(atom), vp))
goto bad;
} else
#endif
{
if (!OBJ_GET_PROPERTY(cx, obj, ATOM_TO_JSID(atom), vp))
goto bad;
}
if (JSVAL_IS_VOID(*vp)) {
default_iter:
/*
* Fail over to the default enumerating native iterator.
*
* Create iterobj with a NULL parent to ensure that we use the correct
* scope chain to lookup the iterator's constructor. Since we use the
* parent slot to keep track of the iterable, we must fix it up after.
*/
iterobj = js_NewObject(cx, &js_IteratorClass, NULL, NULL);
if (!iterobj)
goto bad;
/* Store iterobj in *vp to protect it from GC (callers must root vp). */
*vp = OBJECT_TO_JSVAL(iterobj);
if (!InitNativeIterator(cx, iterobj, obj, flags))
goto bad;
} else {
arg = BOOLEAN_TO_JSVAL((flags & JSITER_FOREACH) == 0);
if (!js_InternalInvoke(cx, obj, *vp, JSINVOKE_ITERATOR, 1, &arg, vp))
goto bad;
if (JSVAL_IS_PRIMITIVE(*vp)) {
str = js_DecompileValueGenerator(cx, JSDVG_SEARCH_STACK, *vp, NULL);
if (str) {
JS_ReportErrorNumberUC(cx, js_GetErrorMessage, NULL,
JSMSG_BAD_ITERATOR_RETURN,
JSSTRING_CHARS(str),
JSSTRING_CHARS(ATOM_TO_STRING(atom)));
}
goto bad;
}
}
ok = JS_TRUE;
out:
if (obj)
JS_POP_TEMP_ROOT(cx, &tvr);
return ok;
bad:
ok = JS_FALSE;
goto out;
}
static JSBool
CallEnumeratorNext(JSContext *cx, JSObject *iterobj, uintN flags, jsval *rval)
{
JSObject *obj, *origobj;
jsval state;
JSBool foreach;
jsid id;
JSObject *obj2;
JSBool cond;
JSClass *clasp;
JSExtendedClass *xclasp;
JSProperty *prop;
JSString *str;
JS_ASSERT(flags & JSITER_ENUMERATE);
JS_ASSERT(JSVAL_TO_PRIVATE(iterobj->slots[JSSLOT_CLASS]) ==
&js_IteratorClass);
obj = JSVAL_TO_OBJECT(iterobj->slots[JSSLOT_PARENT]);
origobj = JSVAL_TO_OBJECT(iterobj->slots[JSSLOT_PROTO]);
state = iterobj->slots[JSSLOT_ITER_STATE];
if (JSVAL_IS_NULL(state))
goto stop;
foreach = (flags & JSITER_FOREACH) != 0;
#if JS_HAS_XML_SUPPORT
/*
* Treat an XML object specially only when it starts the prototype chain.
* Otherwise we need to do the usual deleted and shadowed property checks.
*/
if (obj == origobj && OBJECT_IS_XML(cx, obj)) {
if (foreach) {
JSXMLObjectOps *xmlops = (JSXMLObjectOps *) obj->map->ops;
if (!xmlops->enumerateValues(cx, obj, JSENUMERATE_NEXT, &state,
&id, rval)) {
return JS_FALSE;
}
} else {
if (!OBJ_ENUMERATE(cx, obj, JSENUMERATE_NEXT, &state, &id))
return JS_FALSE;
}
iterobj->slots[JSSLOT_ITER_STATE] = state;
if (JSVAL_IS_NULL(state))
goto stop;
} else
#endif
{
restart:
if (!OBJ_ENUMERATE(cx, obj, JSENUMERATE_NEXT, &state, &id))
return JS_TRUE;
iterobj->slots[JSSLOT_ITER_STATE] = state;
if (JSVAL_IS_NULL(state)) {
#if JS_HAS_XML_SUPPORT
if (OBJECT_IS_XML(cx, obj)) {
/*
* We just finished enumerating an XML obj that is present on
* the prototype chain of a non-XML origobj. Stop further
* prototype chain searches because XML objects don't
* enumerate prototypes.
*/
JS_ASSERT(origobj != obj);
JS_ASSERT(!OBJECT_IS_XML(cx, origobj));
} else
#endif
{
obj = OBJ_GET_PROTO(cx, obj);
if (obj) {
iterobj->slots[JSSLOT_PARENT] = OBJECT_TO_JSVAL(obj);
if (!OBJ_ENUMERATE(cx, obj, JSENUMERATE_INIT, &state, NULL))
return JS_FALSE;
iterobj->slots[JSSLOT_ITER_STATE] = state;
if (!JSVAL_IS_NULL(state))
goto restart;
}
}
goto stop;
}
/* Skip properties not in obj when looking from origobj. */
if (!OBJ_LOOKUP_PROPERTY(cx, origobj, id, &obj2, &prop))
return JS_FALSE;
if (!prop)
goto restart;
OBJ_DROP_PROPERTY(cx, obj2, prop);
/*
* If the id was found in a prototype object or an unrelated object
* (specifically, not in an inner object for obj), skip it. This step
* means that all OBJ_LOOKUP_PROPERTY implementations must return an
* object further along on the prototype chain, or else possibly an
* object returned by the JSExtendedClass.outerObject optional hook.
*/
if (obj != obj2) {
cond = JS_FALSE;
clasp = OBJ_GET_CLASS(cx, obj2);
if (clasp->flags & JSCLASS_IS_EXTENDED) {
xclasp = (JSExtendedClass *) clasp;
cond = xclasp->outerObject &&
xclasp->outerObject(cx, obj2) == obj;
}
if (!cond)
goto restart;
}
if (foreach) {
/* Get property querying the original object. */
if (!OBJ_GET_PROPERTY(cx, origobj, id, rval))
return JS_FALSE;
}
}
if (foreach) {
if (flags & JSITER_KEYVALUE) {
if (!NewKeyValuePair(cx, id, *rval, rval))
return JS_FALSE;
}
} else {
/* Make rval a string for uniformity and compatibility. */
if (JSID_IS_ATOM(id)) {
*rval = ATOM_KEY(JSID_TO_ATOM(id));
}
#if JS_HAS_XML_SUPPORT
else if (JSID_IS_OBJECT(id)) {
str = js_ValueToString(cx, OBJECT_JSID_TO_JSVAL(id));
if (!str)
return JS_FALSE;
*rval = STRING_TO_JSVAL(str);
}
#endif
else {
str = js_NumberToString(cx, (jsdouble)JSID_TO_INT(id));
if (!str)
return JS_FALSE;
*rval = STRING_TO_JSVAL(str);
}
}
return JS_TRUE;
stop:
JS_ASSERT(iterobj->slots[JSSLOT_ITER_STATE] == JSVAL_NULL);
*rval = JSVAL_HOLE;
return JS_TRUE;
}
JSBool
js_CallIteratorNext(JSContext *cx, JSObject *iterobj, jsval *rval)
{
uintN flags;
/* Fast path for native iterators */
if (OBJ_GET_CLASS(cx, iterobj) == &js_IteratorClass) {
flags = JSVAL_TO_INT(OBJ_GET_SLOT(cx, iterobj, JSSLOT_ITER_FLAGS));
if (flags & JSITER_ENUMERATE)
return CallEnumeratorNext(cx, iterobj, flags, rval);
/*
* Call next directly as all the methods of the native iterator are
* read-only and permanent.
*/
if (!IteratorNextImpl(cx, iterobj, rval))
return JS_FALSE;
} else {
jsid id = ATOM_TO_JSID(cx->runtime->atomState.nextAtom);
if (!JS_GetMethodById(cx, iterobj, id, &iterobj, rval))
return JS_FALSE;
if (!js_InternalCall(cx, iterobj, *rval, 0, NULL, rval)) {
/* Check for StopIteration. */
if (!cx->throwing ||
JSVAL_IS_PRIMITIVE(cx->exception) ||
OBJ_GET_CLASS(cx, JSVAL_TO_OBJECT(cx->exception))
!= &js_StopIterationClass) {
return JS_FALSE;
}
/* Inline JS_ClearPendingException(cx). */
cx->throwing = JS_FALSE;
cx->exception = JSVAL_VOID;
*rval = JSVAL_HOLE;
return JS_TRUE;
}
}
return JS_TRUE;
}
static JSBool
stopiter_hasInstance(JSContext *cx, JSObject *obj, jsval v, JSBool *bp)
{
*bp = !JSVAL_IS_PRIMITIVE(v) &&
OBJ_GET_CLASS(cx, JSVAL_TO_OBJECT(v)) == &js_StopIterationClass;
return JS_TRUE;
}
JSClass js_StopIterationClass = {
js_StopIteration_str,
JSCLASS_HAS_CACHED_PROTO(JSProto_StopIteration),
JS_PropertyStub, JS_PropertyStub,
JS_PropertyStub, JS_PropertyStub,
JS_EnumerateStub, JS_ResolveStub,
JS_ConvertStub, JS_FinalizeStub,
NULL, NULL,
NULL, NULL,
NULL, stopiter_hasInstance,
NULL, NULL
};
#if JS_HAS_GENERATORS
static void
generator_finalize(JSContext *cx, JSObject *obj)
{
JSGenerator *gen;
gen = (JSGenerator *) JS_GetPrivate(cx, obj);
if (gen) {
/*
* gen can be open on shutdown when close hooks are ignored or when
* the embedding cancels scheduled close hooks.
*/
JS_ASSERT(gen->state == JSGEN_NEWBORN || gen->state == JSGEN_CLOSED ||
gen->state == JSGEN_OPEN);
JS_free(cx, gen);
}
}
static uint32
generator_mark(JSContext *cx, JSObject *obj, void *arg)
{
JSGenerator *gen;
gen = (JSGenerator *) JS_GetPrivate(cx, obj);
if (gen) {
/*
* We must mark argv[-2], as js_MarkStackFrame will not. Note that
* js_MarkStackFrame will mark thisp (argv[-1]) and actual arguments,
* plus any missing formals and local GC roots.
*/
JS_ASSERT(!JSVAL_IS_PRIMITIVE(gen->frame.argv[-2]));
GC_MARK(cx, JSVAL_TO_GCTHING(gen->frame.argv[-2]), "generator");
js_MarkStackFrame(cx, &gen->frame);
}
return 0;
}
JSClass js_GeneratorClass = {
js_Generator_str,
JSCLASS_HAS_PRIVATE | JSCLASS_IS_ANONYMOUS |
JSCLASS_HAS_CACHED_PROTO(JSProto_Generator),
JS_PropertyStub, JS_PropertyStub, JS_PropertyStub, JS_PropertyStub,
JS_EnumerateStub, JS_ResolveStub, JS_ConvertStub, generator_finalize,
NULL, NULL, NULL, NULL,
NULL, NULL, generator_mark, NULL
};
/*
* Called from the JSOP_GENERATOR case in the interpreter, with fp referring
* to the frame by which the generator function was activated. Create a new
* JSGenerator object, which contains its own JSStackFrame that we populate
* from *fp. We know that upon return, the JSOP_GENERATOR opcode will return
* from the activation in fp, so we can steal away fp->callobj and fp->argsobj
* if they are non-null.
*/
JSObject *
js_NewGenerator(JSContext *cx, JSStackFrame *fp)
{
JSObject *obj;
uintN argc, nargs, nvars, depth, nslots;
JSGenerator *gen;
jsval *newsp;
/* After the following return, failing control flow must goto bad. */
obj = js_NewObject(cx, &js_GeneratorClass, NULL, NULL);
if (!obj)
return NULL;
/* Load and compute stack slot counts. */
argc = fp->argc;
nargs = JS_MAX(argc, fp->fun->nargs);
nvars = fp->nvars;
depth = fp->script->depth;
nslots = 2 + nargs + nvars + 2 * depth;
/* Allocate obj's private data struct. */
gen = (JSGenerator *)
JS_malloc(cx, sizeof(JSGenerator) + (nslots - 1) * sizeof(jsval));
if (!gen)
goto bad;
gen->obj = obj;
/* Steal away objects reflecting fp and point them at gen->frame. */
gen->frame.callobj = fp->callobj;
if (fp->callobj) {
JS_SetPrivate(cx, fp->callobj, &gen->frame);
fp->callobj = NULL;
}
gen->frame.argsobj = fp->argsobj;
if (fp->argsobj) {
JS_SetPrivate(cx, fp->argsobj, &gen->frame);
fp->argsobj = NULL;
}
/* These two references can be shared with fp until it goes away. */
gen->frame.varobj = fp->varobj;
gen->frame.thisp = fp->thisp;
/* Copy call-invariant script and function references. */
gen->frame.script = fp->script;
gen->frame.fun = fp->fun;
/* Use newsp to carve space out of gen->stack. */
newsp = gen->stack;
gen->arena.next = NULL;
gen->arena.base = (jsuword) newsp;
gen->arena.limit = gen->arena.avail = (jsuword) (newsp + nslots);
#define COPY_STACK_ARRAY(vec,cnt,num) \
JS_BEGIN_MACRO \
gen->frame.cnt = cnt; \
gen->frame.vec = newsp; \
newsp += (num); \
memcpy(gen->frame.vec, fp->vec, (num) * sizeof(jsval)); \
JS_END_MACRO
/* Copy argv, rval, and vars. */
*newsp++ = fp->argv[-2];
*newsp++ = fp->argv[-1];
COPY_STACK_ARRAY(argv, argc, nargs);
gen->frame.rval = fp->rval;
COPY_STACK_ARRAY(vars, nvars, nvars);
#undef COPY_STACK_ARRAY
/* Initialize or copy virtual machine state. */
gen->frame.down = NULL;
gen->frame.annotation = NULL;
gen->frame.scopeChain = fp->scopeChain;
gen->frame.pc = fp->pc;
/* Allocate generating pc and operand stack space. */
gen->frame.spbase = gen->frame.sp = newsp + depth;
/* Copy remaining state (XXX sharp* and xml* should be local vars). */
gen->frame.sharpDepth = 0;
gen->frame.sharpArray = NULL;
gen->frame.flags = fp->flags | JSFRAME_GENERATOR;
gen->frame.dormantNext = NULL;
gen->frame.xmlNamespace = NULL;
gen->frame.blockChain = NULL;
/* Note that gen is newborn. */
gen->state = JSGEN_NEWBORN;
if (!JS_SetPrivate(cx, obj, gen)) {
JS_free(cx, gen);
goto bad;
}
/*
* Register with GC to ensure that suspended finally blocks will be
* executed.
*/
js_RegisterGenerator(cx, gen);
return obj;
bad:
cx->weakRoots.newborn[GCX_OBJECT] = NULL;
return NULL;
}
typedef enum JSGeneratorOp {
JSGENOP_NEXT,
JSGENOP_SEND,
JSGENOP_THROW,
JSGENOP_CLOSE
} JSGeneratorOp;
/*
* Start newborn or restart yielding generator and perform the requested
* operation inside its frame.
*/
static JSBool
SendToGenerator(JSContext *cx, JSGeneratorOp op, JSObject *obj,
JSGenerator *gen, jsval arg, jsval *rval)
{
JSStackFrame *fp;
jsval junk;
JSArena *arena;
JSBool ok;
JS_ASSERT(gen->state == JSGEN_NEWBORN || gen->state == JSGEN_OPEN);
switch (op) {
case JSGENOP_NEXT:
case JSGENOP_SEND:
if (gen->state == JSGEN_OPEN) {
/*
* Store the argument to send as the result of the yield
* expression.
*/
gen->frame.sp[-1] = arg;
}
gen->state = JSGEN_RUNNING;
break;
case JSGENOP_THROW:
JS_SetPendingException(cx, arg);
gen->state = JSGEN_RUNNING;
break;
default:
JS_ASSERT(op == JSGENOP_CLOSE);
JS_SetPendingException(cx, JSVAL_ARETURN);
gen->state = JSGEN_CLOSING;
break;
}
/* Extend the current stack pool with gen->arena. */
arena = cx->stackPool.current;
JS_ASSERT(!arena->next);
JS_ASSERT(!gen->arena.next);
JS_ASSERT(cx->stackPool.current != &gen->arena);
cx->stackPool.current = arena->next = &gen->arena;
/* Push gen->frame around the interpreter activation. */
fp = cx->fp;
cx->fp = &gen->frame;
gen->frame.down = fp;
ok = js_Interpret(cx, gen->frame.pc, &junk);
cx->fp = fp;
gen->frame.down = NULL;
/* Retract the stack pool and sanitize gen->arena. */
JS_ASSERT(!gen->arena.next);
JS_ASSERT(arena->next == &gen->arena);
JS_ASSERT(cx->stackPool.current == &gen->arena);
cx->stackPool.current = arena;
arena->next = NULL;
if (gen->frame.flags & JSFRAME_YIELDING) {
/* Yield cannot fail, throw or be called on closing. */
JS_ASSERT(ok);
JS_ASSERT(!cx->throwing);
JS_ASSERT(gen->state == JSGEN_RUNNING);
JS_ASSERT(op != JSGENOP_CLOSE);
gen->frame.flags &= ~JSFRAME_YIELDING;
gen->state = JSGEN_OPEN;
*rval = gen->frame.rval;
return JS_TRUE;
}
gen->state = JSGEN_CLOSED;
if (ok) {
/* Returned, explicitly or by falling off the end. */
if (op == JSGENOP_CLOSE)
return JS_TRUE;
return js_ThrowStopIteration(cx, obj);
}
/*
* An error, silent termination by branch callback or an exception.
* Propagate the condition to the caller.
*/
return JS_FALSE;
}
/*
* Execute gen's close hook after the GC detects that the object has become
* unreachable.
*/
JSBool
js_CloseGeneratorObject(JSContext *cx, JSGenerator *gen)
{
/* We pass null as rval since SendToGenerator never uses it with CLOSE. */
return SendToGenerator(cx, JSGENOP_CLOSE, gen->obj, gen, JSVAL_VOID, NULL);
}
/*
* Common subroutine of generator_(next|send|throw|close) methods.
*/
static JSBool
generator_op(JSContext *cx, JSGeneratorOp op,
JSObject *obj, uintN argc, jsval *argv, jsval *rval)
{
JSGenerator *gen;
JSString *str;
jsval arg;
if (!JS_InstanceOf(cx, obj, &js_GeneratorClass, argv))
return JS_FALSE;
gen = (JSGenerator *) JS_GetPrivate(cx, obj);
if (gen == NULL) {
/* This happens when obj is the generator prototype. See bug 352885. */
goto closed_generator;
}
switch (gen->state) {
case JSGEN_NEWBORN:
switch (op) {
case JSGENOP_NEXT:
case JSGENOP_THROW:
break;
case JSGENOP_SEND:
if (!JSVAL_IS_VOID(argv[0])) {
str = js_DecompileValueGenerator(cx, JSDVG_SEARCH_STACK,
argv[0], NULL);
if (str) {
JS_ReportErrorNumberUC(cx, js_GetErrorMessage, NULL,
JSMSG_BAD_GENERATOR_SEND,
JSSTRING_CHARS(str));
}
return JS_FALSE;
}
break;
default:
JS_ASSERT(op == JSGENOP_CLOSE);
gen->state = JSGEN_CLOSED;
return JS_TRUE;
}
break;
case JSGEN_OPEN:
break;
case JSGEN_RUNNING:
case JSGEN_CLOSING:
str = js_DecompileValueGenerator(cx, JSDVG_SEARCH_STACK, argv[-1],
JS_GetFunctionId(gen->frame.fun));
if (str) {
JS_ReportErrorNumberUC(cx, js_GetErrorMessage, NULL,
JSMSG_NESTING_GENERATOR,
JSSTRING_CHARS(str));
}
return JS_FALSE;
default:
JS_ASSERT(gen->state == JSGEN_CLOSED);
closed_generator:
switch (op) {
case JSGENOP_NEXT:
case JSGENOP_SEND:
return js_ThrowStopIteration(cx, obj);
case JSGENOP_THROW:
JS_SetPendingException(cx, argv[0]);
return JS_FALSE;
default: