forked from mozilla/gecko-dev
-
Notifications
You must be signed in to change notification settings - Fork 2
/
nsCompositeDataSource.cpp
1468 lines (1206 loc) · 44.4 KB
/
nsCompositeDataSource.cpp
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: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/*
A simple composite data source implementation. A composit data
source is just a strategy for combining individual data sources into
a collective graph.
1) A composite data source holds a sequence of data sources. The set
of data sources can be specified during creation of the
database. Data sources can also be added/deleted from a database
later.
2) The aggregation mechanism is based on simple super-positioning of
the graphs from the datasources. If there is a conflict (i.e.,
data source A has a true arc from foo to bar while data source B
has a false arc from foo to bar), the data source that it earlier
in the sequence wins.
The implementation below doesn't really do this and needs to be
fixed.
*/
#include "xpcom-config.h"
#include NEW_H
#include "nsCOMPtr.h"
#include "nsIComponentManager.h"
#include "nsIEnumerator.h"
#include "nsIRDFCompositeDataSource.h"
#include "nsIRDFNode.h"
#include "nsIRDFObserver.h"
#include "nsIRDFRemoteDataSource.h"
#include "nsFixedSizeAllocator.h"
#include "nsTArray.h"
#include "nsCOMArray.h"
#include "nsArrayEnumerator.h"
#include "nsXPIDLString.h"
#include "rdf.h"
#include "nsCycleCollectionParticipant.h"
#include "nsEnumeratorUtils.h"
#ifdef DEBUG
#include "prlog.h"
#include "prprf.h"
#include <stdio.h>
PRLogModuleInfo* nsRDFLog = nullptr;
#endif
static NS_DEFINE_IID(kISupportsIID, NS_ISUPPORTS_IID);
//----------------------------------------------------------------------
//
// CompositeDataSourceImpl
//
class CompositeEnumeratorImpl;
class CompositeArcsInOutEnumeratorImpl;
class CompositeAssertionEnumeratorImpl;
class CompositeDataSourceImpl : public nsIRDFCompositeDataSource,
public nsIRDFObserver
{
public:
CompositeDataSourceImpl(void);
CompositeDataSourceImpl(char** dataSources);
// nsISupports interface
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_CLASS_AMBIGUOUS(CompositeDataSourceImpl,
nsIRDFCompositeDataSource)
// nsIRDFDataSource interface
NS_DECL_NSIRDFDATASOURCE
// nsIRDFCompositeDataSource interface
NS_DECL_NSIRDFCOMPOSITEDATASOURCE
// nsIRDFObserver interface
NS_DECL_NSIRDFOBSERVER
bool HasAssertionN(int n, nsIRDFResource* source,
nsIRDFResource* property,
nsIRDFNode* target,
bool tv);
protected:
nsCOMArray<nsIRDFObserver> mObservers;
nsCOMArray<nsIRDFDataSource> mDataSources;
bool mAllowNegativeAssertions;
bool mCoalesceDuplicateArcs;
int32_t mUpdateBatchNest;
nsFixedSizeAllocator mAllocator;
virtual ~CompositeDataSourceImpl() {}
friend class CompositeEnumeratorImpl;
friend class CompositeArcsInOutEnumeratorImpl;
friend class CompositeAssertionEnumeratorImpl;
};
//----------------------------------------------------------------------
//
// CompositeEnumeratorImpl
//
class CompositeEnumeratorImpl : public nsISimpleEnumerator
{
// nsISupports
NS_DECL_ISUPPORTS
// nsISimpleEnumerator interface
NS_DECL_NSISIMPLEENUMERATOR
// pure abstract methods to be overridden
virtual nsresult
GetEnumerator(nsIRDFDataSource* aDataSource, nsISimpleEnumerator** aResult) = 0;
virtual nsresult
HasNegation(nsIRDFDataSource* aDataSource, nsIRDFNode* aNode, bool* aResult) = 0;
virtual void Destroy() = 0;
protected:
CompositeEnumeratorImpl(CompositeDataSourceImpl* aCompositeDataSource,
bool aAllowNegativeAssertions,
bool aCoalesceDuplicateArcs);
virtual ~CompositeEnumeratorImpl();
CompositeDataSourceImpl* mCompositeDataSource;
nsISimpleEnumerator* mCurrent;
nsIRDFNode* mResult;
int32_t mNext;
nsAutoTArray<nsCOMPtr<nsIRDFNode>, 8> mAlreadyReturned;
bool mAllowNegativeAssertions;
bool mCoalesceDuplicateArcs;
};
CompositeEnumeratorImpl::CompositeEnumeratorImpl(CompositeDataSourceImpl* aCompositeDataSource,
bool aAllowNegativeAssertions,
bool aCoalesceDuplicateArcs)
: mCompositeDataSource(aCompositeDataSource),
mCurrent(nullptr),
mResult(nullptr),
mNext(0),
mAllowNegativeAssertions(aAllowNegativeAssertions),
mCoalesceDuplicateArcs(aCoalesceDuplicateArcs)
{
NS_ADDREF(mCompositeDataSource);
}
CompositeEnumeratorImpl::~CompositeEnumeratorImpl(void)
{
NS_IF_RELEASE(mCurrent);
NS_IF_RELEASE(mResult);
NS_RELEASE(mCompositeDataSource);
}
NS_IMPL_ADDREF(CompositeEnumeratorImpl)
NS_IMPL_RELEASE_WITH_DESTROY(CompositeEnumeratorImpl, Destroy())
NS_IMPL_QUERY_INTERFACE1(CompositeEnumeratorImpl, nsISimpleEnumerator)
NS_IMETHODIMP
CompositeEnumeratorImpl::HasMoreElements(bool* aResult)
{
NS_PRECONDITION(aResult != nullptr, "null ptr");
if (! aResult)
return NS_ERROR_NULL_POINTER;
nsresult rv;
// If we've already queued up a next target, then yep, there are
// more elements.
if (mResult) {
*aResult = true;
return NS_OK;
}
// Otherwise, we'll need to find a next target, switching cursors
// if necessary.
for ( ; mNext < mCompositeDataSource->mDataSources.Count(); ++mNext) {
if (! mCurrent) {
// We don't have a current enumerator, so create a new one on
// the next data source.
nsIRDFDataSource* datasource =
mCompositeDataSource->mDataSources[mNext];
rv = GetEnumerator(datasource, &mCurrent);
if (NS_FAILED(rv)) return rv;
if (rv == NS_RDF_NO_VALUE)
continue;
NS_ASSERTION(mCurrent != nullptr, "you're always supposed to return an enumerator from GetEnumerator, punk.");
if (! mCurrent)
continue;
}
do {
int32_t i;
bool hasMore;
rv = mCurrent->HasMoreElements(&hasMore);
if (NS_FAILED(rv)) return rv;
// Is the current enumerator depleted?
if (! hasMore) {
NS_RELEASE(mCurrent);
break;
}
// Even if the current enumerator has more elements, we still
// need to check that the current element isn't masked by
// a negation in an earlier data source.
// "Peek" ahead and pull out the next target.
nsCOMPtr<nsISupports> result;
rv = mCurrent->GetNext(getter_AddRefs(result));
if (NS_FAILED(rv)) return rv;
rv = result->QueryInterface(NS_GET_IID(nsIRDFNode), (void**) &mResult);
if (NS_FAILED(rv)) return rv;
if (mAllowNegativeAssertions)
{
// See if any previous data source negates this
bool hasNegation = false;
for (i = mNext - 1; i >= 0; --i)
{
nsIRDFDataSource* datasource =
mCompositeDataSource->mDataSources[i];
rv = HasNegation(datasource, mResult, &hasNegation);
if (NS_FAILED(rv)) return rv;
if (hasNegation)
break;
}
// if so, we've gotta keep looking
if (hasNegation)
{
NS_RELEASE(mResult);
continue;
}
}
if (mCoalesceDuplicateArcs)
{
// Now see if we've returned it once already.
// XXX N.B. performance here...may want to hash if things get large?
bool alreadyReturned = false;
for (i = mAlreadyReturned.Length() - 1; i >= 0; --i)
{
if (mAlreadyReturned[i] == mResult)
{
alreadyReturned = true;
break;
}
}
if (alreadyReturned)
{
NS_RELEASE(mResult);
continue;
}
}
// If we get here, then we've really found one. It'll
// remain cached in mResult until GetNext() sucks it out.
*aResult = true;
// Remember that we returned it, so we don't return duplicates.
// XXX I wonder if we should make unique-checking be
// optional. This could get to be pretty expensive (this
// implementation turns iteration into O(n^2)).
if (mCoalesceDuplicateArcs)
{
mAlreadyReturned.AppendElement(mResult);
}
return NS_OK;
} while (1);
}
// if we get here, there aren't any elements left.
*aResult = false;
return NS_OK;
}
NS_IMETHODIMP
CompositeEnumeratorImpl::GetNext(nsISupports** aResult)
{
nsresult rv;
bool hasMore;
rv = HasMoreElements(&hasMore);
if (NS_FAILED(rv)) return rv;
if (! hasMore)
return NS_ERROR_UNEXPECTED;
// Don't AddRef: we "transfer" ownership to the caller
*aResult = mResult;
mResult = nullptr;
return NS_OK;
}
//----------------------------------------------------------------------
//
// CompositeArcsInOutEnumeratorImpl
//
//
class CompositeArcsInOutEnumeratorImpl : public CompositeEnumeratorImpl
{
public:
enum Type { eArcsIn, eArcsOut };
static CompositeArcsInOutEnumeratorImpl*
Create(nsFixedSizeAllocator& aAllocator,
CompositeDataSourceImpl* aCompositeDataSource,
nsIRDFNode* aNode,
Type aType,
bool aAllowNegativeAssertions,
bool aCoalesceDuplicateArcs) {
void* place = aAllocator.Alloc(sizeof(CompositeArcsInOutEnumeratorImpl));
return place
? ::new (place) CompositeArcsInOutEnumeratorImpl(aCompositeDataSource,
aNode, aType,
aAllowNegativeAssertions,
aCoalesceDuplicateArcs)
: nullptr; }
virtual ~CompositeArcsInOutEnumeratorImpl();
virtual nsresult
GetEnumerator(nsIRDFDataSource* aDataSource, nsISimpleEnumerator** aResult);
virtual nsresult
HasNegation(nsIRDFDataSource* aDataSource, nsIRDFNode* aNode, bool* aResult);
virtual void Destroy();
protected:
CompositeArcsInOutEnumeratorImpl(CompositeDataSourceImpl* aCompositeDataSource,
nsIRDFNode* aNode,
Type aType,
bool aAllowNegativeAssertions,
bool aCoalesceDuplicateArcs);
private:
nsIRDFNode* mNode;
Type mType;
// Hide so that only Create() and Destroy() can be used to
// allocate and deallocate from the heap
static void* operator new(size_t) CPP_THROW_NEW { return 0; }
static void operator delete(void*, size_t) {}
};
CompositeArcsInOutEnumeratorImpl::CompositeArcsInOutEnumeratorImpl(
CompositeDataSourceImpl* aCompositeDataSource,
nsIRDFNode* aNode,
Type aType,
bool aAllowNegativeAssertions,
bool aCoalesceDuplicateArcs)
: CompositeEnumeratorImpl(aCompositeDataSource, aAllowNegativeAssertions, aCoalesceDuplicateArcs),
mNode(aNode),
mType(aType)
{
NS_ADDREF(mNode);
}
CompositeArcsInOutEnumeratorImpl::~CompositeArcsInOutEnumeratorImpl()
{
NS_RELEASE(mNode);
}
nsresult
CompositeArcsInOutEnumeratorImpl::GetEnumerator(
nsIRDFDataSource* aDataSource,
nsISimpleEnumerator** aResult)
{
if (mType == eArcsIn) {
return aDataSource->ArcLabelsIn(mNode, aResult);
}
else {
nsCOMPtr<nsIRDFResource> resource( do_QueryInterface(mNode) );
return aDataSource->ArcLabelsOut(resource, aResult);
}
}
nsresult
CompositeArcsInOutEnumeratorImpl::HasNegation(
nsIRDFDataSource* aDataSource,
nsIRDFNode* aNode,
bool* aResult)
{
*aResult = false;
return NS_OK;
}
void
CompositeArcsInOutEnumeratorImpl::Destroy()
{
// Keep the datasource alive for the duration of the stack
// frame so its allocator stays valid.
nsCOMPtr<nsIRDFCompositeDataSource> kungFuDeathGrip = mCompositeDataSource;
nsFixedSizeAllocator& pool = mCompositeDataSource->mAllocator;
this->~CompositeArcsInOutEnumeratorImpl();
pool.Free(this, sizeof(*this));
}
//----------------------------------------------------------------------
//
// CompositeAssertionEnumeratorImpl
//
class CompositeAssertionEnumeratorImpl : public CompositeEnumeratorImpl
{
public:
static CompositeAssertionEnumeratorImpl*
Create(nsFixedSizeAllocator& aAllocator,
CompositeDataSourceImpl* aCompositeDataSource,
nsIRDFResource* aSource,
nsIRDFResource* aProperty,
nsIRDFNode* aTarget,
bool aTruthValue,
bool aAllowNegativeAssertions,
bool aCoalesceDuplicateArcs) {
void* place = aAllocator.Alloc(sizeof(CompositeAssertionEnumeratorImpl));
return place
? ::new (place) CompositeAssertionEnumeratorImpl(aCompositeDataSource,
aSource, aProperty, aTarget,
aTruthValue,
aAllowNegativeAssertions,
aCoalesceDuplicateArcs)
: nullptr; }
virtual nsresult
GetEnumerator(nsIRDFDataSource* aDataSource, nsISimpleEnumerator** aResult);
virtual nsresult
HasNegation(nsIRDFDataSource* aDataSource, nsIRDFNode* aNode, bool* aResult);
virtual void Destroy();
protected:
CompositeAssertionEnumeratorImpl(CompositeDataSourceImpl* aCompositeDataSource,
nsIRDFResource* aSource,
nsIRDFResource* aProperty,
nsIRDFNode* aTarget,
bool aTruthValue,
bool aAllowNegativeAssertions,
bool aCoalesceDuplicateArcs);
virtual ~CompositeAssertionEnumeratorImpl();
private:
nsIRDFResource* mSource;
nsIRDFResource* mProperty;
nsIRDFNode* mTarget;
bool mTruthValue;
// Hide so that only Create() and Destroy() can be used to
// allocate and deallocate from the heap
static void* operator new(size_t) CPP_THROW_NEW { return 0; }
static void operator delete(void*, size_t) {}
};
CompositeAssertionEnumeratorImpl::CompositeAssertionEnumeratorImpl(
CompositeDataSourceImpl* aCompositeDataSource,
nsIRDFResource* aSource,
nsIRDFResource* aProperty,
nsIRDFNode* aTarget,
bool aTruthValue,
bool aAllowNegativeAssertions,
bool aCoalesceDuplicateArcs)
: CompositeEnumeratorImpl(aCompositeDataSource, aAllowNegativeAssertions, aCoalesceDuplicateArcs),
mSource(aSource),
mProperty(aProperty),
mTarget(aTarget),
mTruthValue(aTruthValue)
{
NS_IF_ADDREF(mSource);
NS_ADDREF(mProperty); // always must be specified
NS_IF_ADDREF(mTarget);
}
CompositeAssertionEnumeratorImpl::~CompositeAssertionEnumeratorImpl()
{
NS_IF_RELEASE(mSource);
NS_RELEASE(mProperty);
NS_IF_RELEASE(mTarget);
}
nsresult
CompositeAssertionEnumeratorImpl::GetEnumerator(
nsIRDFDataSource* aDataSource,
nsISimpleEnumerator** aResult)
{
if (mSource) {
return aDataSource->GetTargets(mSource, mProperty, mTruthValue, aResult);
}
else {
return aDataSource->GetSources(mProperty, mTarget, mTruthValue, aResult);
}
}
nsresult
CompositeAssertionEnumeratorImpl::HasNegation(
nsIRDFDataSource* aDataSource,
nsIRDFNode* aNode,
bool* aResult)
{
if (mSource) {
return aDataSource->HasAssertion(mSource, mProperty, aNode, !mTruthValue, aResult);
}
else {
nsCOMPtr<nsIRDFResource> source( do_QueryInterface(aNode) );
return aDataSource->HasAssertion(source, mProperty, mTarget, !mTruthValue, aResult);
}
}
void
CompositeAssertionEnumeratorImpl::Destroy()
{
// Keep the datasource alive for the duration of the stack
// frame so its allocator stays valid.
nsCOMPtr<nsIRDFCompositeDataSource> kungFuDeathGrip = mCompositeDataSource;
nsFixedSizeAllocator& pool = mCompositeDataSource->mAllocator;
this->~CompositeAssertionEnumeratorImpl();
pool.Free(this, sizeof(*this));
}
////////////////////////////////////////////////////////////////////////
nsresult
NS_NewRDFCompositeDataSource(nsIRDFCompositeDataSource** result)
{
CompositeDataSourceImpl* db = new CompositeDataSourceImpl();
if (! db)
return NS_ERROR_OUT_OF_MEMORY;
*result = db;
NS_ADDREF(*result);
return NS_OK;
}
CompositeDataSourceImpl::CompositeDataSourceImpl(void)
: mAllowNegativeAssertions(true),
mCoalesceDuplicateArcs(true),
mUpdateBatchNest(0)
{
static const size_t kBucketSizes[] = {
sizeof(CompositeAssertionEnumeratorImpl),
sizeof(CompositeArcsInOutEnumeratorImpl) };
static const int32_t kNumBuckets = sizeof(kBucketSizes) / sizeof(size_t);
// Per news://news.mozilla.org/39BEC105.5090206%40netscape.com
static const int32_t kInitialSize = 256;
mAllocator.Init("nsCompositeDataSource", kBucketSizes, kNumBuckets, kInitialSize);
#ifdef PR_LOGGING
if (nsRDFLog == nullptr)
nsRDFLog = PR_NewLogModule("RDF");
#endif
}
//----------------------------------------------------------------------
//
// nsISupports interface
//
NS_IMPL_CYCLE_COLLECTION_CLASS(CompositeDataSourceImpl)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(CompositeDataSourceImpl)
uint32_t i, count = tmp->mDataSources.Count();
for (i = count; i > 0; --i) {
tmp->mDataSources[i - 1]->RemoveObserver(tmp);
tmp->mDataSources.RemoveObjectAt(i - 1);
}
NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMARRAY(mObservers);
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(CompositeDataSourceImpl)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSCOMARRAY(mObservers)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSCOMARRAY(mDataSources)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTING_ADDREF(CompositeDataSourceImpl)
NS_IMPL_CYCLE_COLLECTING_RELEASE(CompositeDataSourceImpl)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(CompositeDataSourceImpl)
NS_INTERFACE_MAP_ENTRY(nsIRDFCompositeDataSource)
NS_INTERFACE_MAP_ENTRY(nsIRDFDataSource)
NS_INTERFACE_MAP_ENTRY(nsIRDFObserver)
NS_INTERFACE_MAP_ENTRY(nsIRDFCompositeDataSource)
NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIRDFCompositeDataSource)
NS_INTERFACE_MAP_END
//----------------------------------------------------------------------
//
// nsIRDFDataSource interface
//
NS_IMETHODIMP
CompositeDataSourceImpl::GetURI(char* *uri)
{
*uri = nullptr;
return NS_OK;
}
NS_IMETHODIMP
CompositeDataSourceImpl::GetSource(nsIRDFResource* property,
nsIRDFNode* target,
bool tv,
nsIRDFResource** source)
{
if (!mAllowNegativeAssertions && !tv)
return(NS_RDF_NO_VALUE);
int32_t count = mDataSources.Count();
for (int32_t i = 0; i < count; ++i) {
nsresult rv;
rv = mDataSources[i]->GetSource(property, target, tv, source);
if (NS_FAILED(rv)) return rv;
if (rv == NS_RDF_NO_VALUE)
continue;
if (!mAllowNegativeAssertions) return(NS_OK);
// okay, found it. make sure we don't have the opposite
// asserted in a more local data source
if (!HasAssertionN(count-1, *source, property, target, !tv))
return NS_OK;
NS_RELEASE(*source);
return NS_RDF_NO_VALUE;
}
return NS_RDF_NO_VALUE;
}
NS_IMETHODIMP
CompositeDataSourceImpl::GetSources(nsIRDFResource* aProperty,
nsIRDFNode* aTarget,
bool aTruthValue,
nsISimpleEnumerator** aResult)
{
NS_PRECONDITION(aProperty != nullptr, "null ptr");
if (! aProperty)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aTarget != nullptr, "null ptr");
if (! aTarget)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aResult != nullptr, "null ptr");
if (! aResult)
return NS_ERROR_NULL_POINTER;
if (! mAllowNegativeAssertions && ! aTruthValue)
return(NS_RDF_NO_VALUE);
*aResult = CompositeAssertionEnumeratorImpl::Create(mAllocator,
this, nullptr, aProperty,
aTarget, aTruthValue,
mAllowNegativeAssertions,
mCoalesceDuplicateArcs);
if (! *aResult)
return NS_ERROR_OUT_OF_MEMORY;
NS_ADDREF(*aResult);
return NS_OK;
}
NS_IMETHODIMP
CompositeDataSourceImpl::GetTarget(nsIRDFResource* aSource,
nsIRDFResource* aProperty,
bool aTruthValue,
nsIRDFNode** aResult)
{
NS_PRECONDITION(aSource != nullptr, "null ptr");
if (! aSource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aProperty != nullptr, "null ptr");
if (! aProperty)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aResult != nullptr, "null ptr");
if (! aResult)
return NS_ERROR_NULL_POINTER;
if (! mAllowNegativeAssertions && ! aTruthValue)
return(NS_RDF_NO_VALUE);
int32_t count = mDataSources.Count();
for (int32_t i = 0; i < count; ++i) {
nsresult rv;
rv = mDataSources[i]->GetTarget(aSource, aProperty, aTruthValue,
aResult);
if (NS_FAILED(rv))
return rv;
if (rv == NS_OK) {
// okay, found it. make sure we don't have the opposite
// asserted in an earlier data source
if (mAllowNegativeAssertions) {
if (HasAssertionN(count-1, aSource, aProperty, *aResult, !aTruthValue)) {
// whoops, it's been negated.
NS_RELEASE(*aResult);
return NS_RDF_NO_VALUE;
}
}
return NS_OK;
}
}
// Otherwise, we couldn't find it at all.
return NS_RDF_NO_VALUE;
}
bool
CompositeDataSourceImpl::HasAssertionN(int n,
nsIRDFResource* aSource,
nsIRDFResource* aProperty,
nsIRDFNode* aTarget,
bool aTruthValue)
{
nsresult rv;
for (int32_t m = 0; m < n; ++m) {
bool result;
rv = mDataSources[m]->HasAssertion(aSource, aProperty, aTarget,
aTruthValue, &result);
if (NS_FAILED(rv))
return false;
// found it!
if (result)
return true;
}
return false;
}
NS_IMETHODIMP
CompositeDataSourceImpl::GetTargets(nsIRDFResource* aSource,
nsIRDFResource* aProperty,
bool aTruthValue,
nsISimpleEnumerator** aResult)
{
NS_PRECONDITION(aSource != nullptr, "null ptr");
if (! aSource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aProperty != nullptr, "null ptr");
if (! aProperty)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aResult != nullptr, "null ptr");
if (! aResult)
return NS_ERROR_NULL_POINTER;
if (! mAllowNegativeAssertions && ! aTruthValue)
return(NS_RDF_NO_VALUE);
*aResult =
CompositeAssertionEnumeratorImpl::Create(mAllocator, this,
aSource, aProperty, nullptr,
aTruthValue,
mAllowNegativeAssertions,
mCoalesceDuplicateArcs);
if (! *aResult)
return NS_ERROR_OUT_OF_MEMORY;
NS_ADDREF(*aResult);
return NS_OK;
}
NS_IMETHODIMP
CompositeDataSourceImpl::Assert(nsIRDFResource* aSource,
nsIRDFResource* aProperty,
nsIRDFNode* aTarget,
bool aTruthValue)
{
NS_PRECONDITION(aSource != nullptr, "null ptr");
if (! aSource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aProperty != nullptr, "null ptr");
if (! aProperty)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aTarget != nullptr, "null ptr");
if (! aTarget)
return NS_ERROR_NULL_POINTER;
if (! mAllowNegativeAssertions && ! aTruthValue)
return(NS_RDF_ASSERTION_REJECTED);
nsresult rv;
// XXX Need to add back the stuff for unblocking ...
// We iterate backwards from the last data source which was added
// ("the most remote") to the first ("the most local"), trying to
// apply the assertion in each.
for (int32_t i = mDataSources.Count() - 1; i >= 0; --i) {
rv = mDataSources[i]->Assert(aSource, aProperty, aTarget, aTruthValue);
if (NS_RDF_ASSERTION_ACCEPTED == rv)
return rv;
if (NS_FAILED(rv))
return rv;
}
// nobody wanted to accept it
return NS_RDF_ASSERTION_REJECTED;
}
NS_IMETHODIMP
CompositeDataSourceImpl::Unassert(nsIRDFResource* aSource,
nsIRDFResource* aProperty,
nsIRDFNode* aTarget)
{
NS_PRECONDITION(aSource != nullptr, "null ptr");
if (! aSource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aProperty != nullptr, "null ptr");
if (! aProperty)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aTarget != nullptr, "null ptr");
if (! aTarget)
return NS_ERROR_NULL_POINTER;
nsresult rv;
// Iterate through each of the datasources, starting with "the
// most local" and moving to "the most remote". If _any_ of the
// datasources have the assertion, attempt to unassert it.
bool unasserted = true;
int32_t i;
int32_t count = mDataSources.Count();
for (i = 0; i < count; ++i) {
nsIRDFDataSource* ds = mDataSources[i];
bool hasAssertion;
rv = ds->HasAssertion(aSource, aProperty, aTarget, true, &hasAssertion);
if (NS_FAILED(rv)) return rv;
if (hasAssertion) {
rv = ds->Unassert(aSource, aProperty, aTarget);
if (NS_FAILED(rv)) return rv;
if (rv != NS_RDF_ASSERTION_ACCEPTED) {
unasserted = false;
break;
}
}
}
// Either none of the datasources had it, or they were all willing
// to let it be unasserted.
if (unasserted)
return NS_RDF_ASSERTION_ACCEPTED;
// If we get here, one of the datasources already had the
// assertion, and was adamant about not letting us remove
// it. Iterate from the "most local" to the "most remote"
// attempting to assert the negation...
for (i = 0; i < count; ++i) {
rv = mDataSources[i]->Assert(aSource, aProperty, aTarget, false);
if (NS_FAILED(rv)) return rv;
// Did it take?
if (rv == NS_RDF_ASSERTION_ACCEPTED)
return rv;
}
// Couln't get anyone to accept the negation, either.
return NS_RDF_ASSERTION_REJECTED;
}
NS_IMETHODIMP
CompositeDataSourceImpl::Change(nsIRDFResource* aSource,
nsIRDFResource* aProperty,
nsIRDFNode* aOldTarget,
nsIRDFNode* aNewTarget)
{
NS_PRECONDITION(aSource != nullptr, "null ptr");
if (! aSource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aProperty != nullptr, "null ptr");
if (! aProperty)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aOldTarget != nullptr, "null ptr");
if (! aOldTarget)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aNewTarget != nullptr, "null ptr");
if (! aNewTarget)
return NS_ERROR_NULL_POINTER;
nsresult rv;
// XXX So we're assuming that a datasource _must_ accept the
// atomic change; i.e., we can't split it up across two
// datasources. That sucks.
// We iterate backwards from the last data source which was added
// ("the most remote") to the first ("the most local"), trying to
// apply the change in each.
for (int32_t i = mDataSources.Count() - 1; i >= 0; --i) {
rv = mDataSources[i]->Change(aSource, aProperty, aOldTarget, aNewTarget);
if (NS_RDF_ASSERTION_ACCEPTED == rv)
return rv;
if (NS_FAILED(rv))
return rv;
}
// nobody wanted to accept it
return NS_RDF_ASSERTION_REJECTED;
}
NS_IMETHODIMP
CompositeDataSourceImpl::Move(nsIRDFResource* aOldSource,
nsIRDFResource* aNewSource,
nsIRDFResource* aProperty,
nsIRDFNode* aTarget)
{
NS_PRECONDITION(aOldSource != nullptr, "null ptr");
if (! aOldSource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aNewSource != nullptr, "null ptr");
if (! aNewSource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aProperty != nullptr, "null ptr");
if (! aProperty)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aTarget != nullptr, "null ptr");
if (! aTarget)
return NS_ERROR_NULL_POINTER;
nsresult rv;
// XXX So we're assuming that a datasource _must_ accept the
// atomic move; i.e., we can't split it up across two
// datasources. That sucks.
// We iterate backwards from the last data source which was added
// ("the most remote") to the first ("the most local"), trying to
// apply the assertion in each.
for (int32_t i = mDataSources.Count() - 1; i >= 0; --i) {
rv = mDataSources[i]->Move(aOldSource, aNewSource, aProperty, aTarget);
if (NS_RDF_ASSERTION_ACCEPTED == rv)
return rv;
if (NS_FAILED(rv))
return rv;
}
// nobody wanted to accept it