File: IDBDatabaseBackend.cpp

package info (click to toggle)
webkit2gtk 2.6.2%2Bdfsg1-4
  • links: PTS, VCS
  • area: main
  • in suites: jessie, jessie-kfreebsd
  • size: 115,572 kB
  • ctags: 216,388
  • sloc: cpp: 1,164,175; ansic: 18,422; perl: 16,884; python: 11,608; ruby: 9,409; xml: 8,376; asm: 4,765; yacc: 2,292; lex: 891; sh: 650; makefile: 79
file content (622 lines) | stat: -rw-r--r-- 27,461 bytes parent folder | download
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
/*
 * Copyright (C) 2011 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"
#include "IDBDatabaseBackend.h"

#if ENABLE(INDEXED_DATABASE)

#include "IDBCursorBackend.h"
#include "IDBDatabaseCallbacks.h"
#include "IDBDatabaseException.h"
#include "IDBFactoryBackendInterface.h"
#include "IDBKeyRange.h"
#include "IDBRecordIdentifier.h"
#include "IDBServerConnection.h"
#include "IDBTransactionBackend.h"
#include "IDBTransactionCoordinator.h"
#include "Logging.h"
#include "SharedBuffer.h"
#include <wtf/TemporaryChange.h>

namespace WebCore {

PassRefPtr<IDBDatabaseBackend> IDBDatabaseBackend::create(const String& name, const String& uniqueIdentifier, IDBFactoryBackendInterface* factory, IDBServerConnection& serverConnection)
{
    RefPtr<IDBDatabaseBackend> backend = adoptRef(new IDBDatabaseBackend(name, uniqueIdentifier, factory, serverConnection));
    backend->openInternalAsync();
    
    return backend.release();
}

IDBDatabaseBackend::IDBDatabaseBackend(const String& name, const String& uniqueIdentifier, IDBFactoryBackendInterface* factory, IDBServerConnection& serverConnection)
    : m_metadata(name, InvalidId, 0, InvalidId)
    , m_identifier(uniqueIdentifier)
    , m_factory(factory)
    , m_serverConnection(serverConnection)
    , m_transactionCoordinator(std::make_unique<IDBTransactionCoordinator>())
    , m_closingConnection(false)
    , m_didOpenInternal(false)
{
    ASSERT(!m_metadata.name.isNull());
}

void IDBDatabaseBackend::addObjectStore(const IDBObjectStoreMetadata& objectStore, int64_t newMaxObjectStoreId)
{
    ASSERT(!m_metadata.objectStores.contains(objectStore.id));
    if (newMaxObjectStoreId != IDBObjectStoreMetadata::InvalidId) {
        ASSERT(m_metadata.maxObjectStoreId < newMaxObjectStoreId);
        m_metadata.maxObjectStoreId = newMaxObjectStoreId;
    }
    m_metadata.objectStores.set(objectStore.id, objectStore);
}

void IDBDatabaseBackend::removeObjectStore(int64_t objectStoreId)
{
    ASSERT(m_metadata.objectStores.contains(objectStoreId));
    m_metadata.objectStores.remove(objectStoreId);
}

void IDBDatabaseBackend::addIndex(int64_t objectStoreId, const IDBIndexMetadata& index, int64_t newMaxIndexId)
{
    ASSERT(m_metadata.objectStores.contains(objectStoreId));
    IDBObjectStoreMetadata objectStore = m_metadata.objectStores.get(objectStoreId);

    ASSERT(!objectStore.indexes.contains(index.id));
    objectStore.indexes.set(index.id, index);
    if (newMaxIndexId != IDBIndexMetadata::InvalidId) {
        ASSERT(objectStore.maxIndexId < newMaxIndexId);
        objectStore.maxIndexId = newMaxIndexId;
    }
    m_metadata.objectStores.set(objectStoreId, objectStore);
}

void IDBDatabaseBackend::removeIndex(int64_t objectStoreId, int64_t indexId)
{
    ASSERT(m_metadata.objectStores.contains(objectStoreId));
    IDBObjectStoreMetadata objectStore = m_metadata.objectStores.get(objectStoreId);

    ASSERT(objectStore.indexes.contains(indexId));
    objectStore.indexes.remove(indexId);
    m_metadata.objectStores.set(objectStoreId, objectStore);
}

void IDBDatabaseBackend::openInternalAsync()
{
    RefPtr<IDBDatabaseBackend> self = this;
    m_serverConnection->getOrEstablishIDBDatabaseMetadata([self](const IDBDatabaseMetadata& metadata, bool success) {
        self->didOpenInternalAsync(metadata, success);
    });
}

void IDBDatabaseBackend::didOpenInternalAsync(const IDBDatabaseMetadata& metadata, bool success)
{
    m_didOpenInternal = true;

    if (!success) {
        processPendingOpenCalls(false);
        return;
    }

    m_metadata = metadata;

    processPendingCalls();
}

IDBDatabaseBackend::~IDBDatabaseBackend()
{
    m_factory->removeIDBDatabaseBackend(m_identifier);
}

void IDBDatabaseBackend::createObjectStore(int64_t transactionId, int64_t objectStoreId, const String& name, const IDBKeyPath& keyPath, bool autoIncrement)
{
    LOG(StorageAPI, "IDBDatabaseBackend::createObjectStore");
    IDBTransactionBackend* transaction = m_transactions.get(transactionId);
    if (!transaction)
        return;
    ASSERT(transaction->mode() == IndexedDB::TransactionMode::VersionChange);

    ASSERT(!m_metadata.objectStores.contains(objectStoreId));
    IDBObjectStoreMetadata objectStoreMetadata(name, objectStoreId, keyPath, autoIncrement, IDBDatabaseBackend::MinimumIndexId);

    transaction->scheduleCreateObjectStoreOperation(objectStoreMetadata);
    addObjectStore(objectStoreMetadata, objectStoreId);
}

void IDBDatabaseBackend::deleteObjectStore(int64_t transactionId, int64_t objectStoreId)
{
    LOG(StorageAPI, "IDBDatabaseBackend::deleteObjectStore");
    IDBTransactionBackend* transaction = m_transactions.get(transactionId);
    if (!transaction)
        return;
    ASSERT(transaction->mode() == IndexedDB::TransactionMode::VersionChange);

    ASSERT(m_metadata.objectStores.contains(objectStoreId));
    const IDBObjectStoreMetadata& objectStoreMetadata = m_metadata.objectStores.get(objectStoreId);

    transaction->scheduleDeleteObjectStoreOperation(objectStoreMetadata);
    removeObjectStore(objectStoreId);
}

void IDBDatabaseBackend::createIndex(int64_t transactionId, int64_t objectStoreId, int64_t indexId, const String& name, const IDBKeyPath& keyPath, bool unique, bool multiEntry)
{
    LOG(StorageAPI, "IDBDatabaseBackend::createIndex");
    IDBTransactionBackend* transaction = m_transactions.get(transactionId);
    if (!transaction)
        return;
    ASSERT(transaction->mode() == IndexedDB::TransactionMode::VersionChange);

    ASSERT(m_metadata.objectStores.contains(objectStoreId));
    const IDBObjectStoreMetadata objectStore = m_metadata.objectStores.get(objectStoreId);

    ASSERT(!objectStore.indexes.contains(indexId));
    const IDBIndexMetadata indexMetadata(name, indexId, keyPath, unique, multiEntry);

    transaction->scheduleCreateIndexOperation(objectStoreId, indexMetadata);

    addIndex(objectStoreId, indexMetadata, indexId);
}

void IDBDatabaseBackend::deleteIndex(int64_t transactionId, int64_t objectStoreId, int64_t indexId)
{
    LOG(StorageAPI, "IDBDatabaseBackend::deleteIndex");
    IDBTransactionBackend* transaction = m_transactions.get(transactionId);
    if (!transaction)
        return;
    ASSERT(transaction->mode() == IndexedDB::TransactionMode::VersionChange);

    ASSERT(m_metadata.objectStores.contains(objectStoreId));
    const IDBObjectStoreMetadata objectStore = m_metadata.objectStores.get(objectStoreId);

    ASSERT(objectStore.indexes.contains(indexId));
    const IDBIndexMetadata& indexMetadata = objectStore.indexes.get(indexId);

    transaction->scheduleDeleteIndexOperation(objectStoreId, indexMetadata);

    removeIndex(objectStoreId, indexId);
}

void IDBDatabaseBackend::commit(int64_t transactionId)
{
    // The frontend suggests that we commit, but we may have previously initiated an abort, and so have disposed of the transaction. onAbort has already been dispatched to the frontend, so it will find out about that asynchronously.
    if (m_transactions.contains(transactionId))
        m_transactions.get(transactionId)->commit();
}

void IDBDatabaseBackend::abort(int64_t transactionId)
{
    // If the transaction is unknown, then it has already been aborted by the backend before this call so it is safe to ignore it.
    if (m_transactions.contains(transactionId))
        m_transactions.get(transactionId)->abort();
}

void IDBDatabaseBackend::abort(int64_t transactionId, PassRefPtr<IDBDatabaseError> error)
{
    // If the transaction is unknown, then it has already been aborted by the backend before this call so it is safe to ignore it.
    if (m_transactions.contains(transactionId))
        m_transactions.get(transactionId)->abort(error);
}

void IDBDatabaseBackend::get(int64_t transactionId, int64_t objectStoreId, int64_t indexId, PassRefPtr<IDBKeyRange> keyRange, bool keyOnly, PassRefPtr<IDBCallbacks> callbacks)
{
    LOG(StorageAPI, "IDBDatabaseBackend::get");
    IDBTransactionBackend* transaction = m_transactions.get(transactionId);
    if (!transaction)
        return;

    transaction->scheduleGetOperation(m_metadata, objectStoreId, indexId, keyRange, keyOnly ? IndexedDB::CursorType::KeyOnly : IndexedDB::CursorType::KeyAndValue, callbacks);
}

void IDBDatabaseBackend::put(int64_t transactionId, int64_t objectStoreId, PassRefPtr<SharedBuffer> value, PassRefPtr<IDBKey> key, PutMode putMode, PassRefPtr<IDBCallbacks> callbacks, const Vector<int64_t>& indexIds, const Vector<IndexKeys>& indexKeys)
{
    LOG(StorageAPI, "IDBDatabaseBackend::put");
    IDBTransactionBackend* transaction = m_transactions.get(transactionId);
    if (!transaction)
        return;
    ASSERT(transaction->mode() != IndexedDB::TransactionMode::ReadOnly);

    const IDBObjectStoreMetadata objectStoreMetadata = m_metadata.objectStores.get(objectStoreId);

    ASSERT(objectStoreMetadata.autoIncrement || key.get());

    transaction->schedulePutOperation(objectStoreMetadata, value, key, putMode, callbacks, indexIds, indexKeys);
}

void IDBDatabaseBackend::setIndexKeys(int64_t transactionID, int64_t objectStoreID, PassRefPtr<IDBKey> prpPrimaryKey, const Vector<int64_t>& indexIDs, const Vector<IndexKeys>& indexKeys)
{
    LOG(StorageAPI, "IDBDatabaseBackend::setIndexKeys");
    ASSERT(prpPrimaryKey);
    ASSERT(m_metadata.objectStores.contains(objectStoreID));

    RefPtr<IDBTransactionBackend> transaction = m_transactions.get(transactionID);
    if (!transaction)
        return;
    ASSERT(transaction->mode() == IndexedDB::TransactionMode::VersionChange);

    RefPtr<IDBKey> primaryKey = prpPrimaryKey;
    m_serverConnection->setIndexKeys(transactionID, m_metadata.id, objectStoreID, m_metadata.objectStores.get(objectStoreID), *primaryKey, indexIDs, indexKeys, [transaction](PassRefPtr<IDBDatabaseError> error) {
        if (error)
            transaction->abort(error);
    });
}

void IDBDatabaseBackend::setIndexesReady(int64_t transactionId, int64_t, const Vector<int64_t>& indexIds)
{
    LOG(StorageAPI, "IDBDatabaseBackend::setIndexesReady");

    IDBTransactionBackend* transaction = m_transactions.get(transactionId);
    if (!transaction)
        return;

    transaction->scheduleSetIndexesReadyOperation(indexIds.size());
}

void IDBDatabaseBackend::openCursor(int64_t transactionId, int64_t objectStoreId, int64_t indexId, PassRefPtr<IDBKeyRange> keyRange, IndexedDB::CursorDirection direction, bool keyOnly, TaskType taskType, PassRefPtr<IDBCallbacks> callbacks)
{
    LOG(StorageAPI, "IDBDatabaseBackend::openCursor");
    IDBTransactionBackend* transaction = m_transactions.get(transactionId);
    if (!transaction)
        return;

    transaction->scheduleOpenCursorOperation(objectStoreId, indexId, keyRange, direction, keyOnly ? IndexedDB::CursorType::KeyOnly : IndexedDB::CursorType::KeyAndValue, taskType, callbacks);
}

void IDBDatabaseBackend::count(int64_t transactionId, int64_t objectStoreId, int64_t indexId, PassRefPtr<IDBKeyRange> keyRange, PassRefPtr<IDBCallbacks> callbacks)
{
    LOG(StorageAPI, "IDBDatabaseBackend::count");
    IDBTransactionBackend* transaction = m_transactions.get(transactionId);
    if (!transaction)
        return;

    ASSERT(m_metadata.objectStores.contains(objectStoreId));
    transaction->scheduleCountOperation(objectStoreId, indexId, keyRange, callbacks);
}


void IDBDatabaseBackend::deleteRange(int64_t transactionId, int64_t objectStoreId, PassRefPtr<IDBKeyRange> keyRange, PassRefPtr<IDBCallbacks> callbacks)
{
    LOG(StorageAPI, "IDBDatabaseBackend::deleteRange");
    IDBTransactionBackend* transaction = m_transactions.get(transactionId);
    if (!transaction)
        return;
    ASSERT(transaction->mode() != IndexedDB::TransactionMode::ReadOnly);

    transaction->scheduleDeleteRangeOperation(objectStoreId, keyRange, callbacks);
}

void IDBDatabaseBackend::clearObjectStore(int64_t transactionId, int64_t objectStoreId, PassRefPtr<IDBCallbacks> callbacks)
{
    LOG(StorageAPI, "IDBDatabaseBackend::clearObjectStore %lli in transaction %lli", static_cast<long long>(objectStoreId), static_cast<long long>(transactionId));
    IDBTransactionBackend* transaction = m_transactions.get(transactionId);
    if (!transaction)
        return;
    ASSERT(transaction->mode() != IndexedDB::TransactionMode::ReadOnly);

    transaction->scheduleClearObjectStoreOperation(objectStoreId, callbacks);
}

void IDBDatabaseBackend::transactionStarted(IDBTransactionBackend* transaction)
{
    if (transaction->mode() == IndexedDB::TransactionMode::VersionChange) {
        ASSERT(!m_runningVersionChangeTransaction);
        m_runningVersionChangeTransaction = transaction;
    }
}

void IDBDatabaseBackend::transactionFinished(IDBTransactionBackend* rawTransaction)
{
    RefPtr<IDBTransactionBackend> transaction = rawTransaction;
    ASSERT(m_transactions.contains(transaction->id()));
    ASSERT(m_transactions.get(transaction->id()) == transaction.get());
    m_transactions.remove(transaction->id());
    if (transaction->mode() == IndexedDB::TransactionMode::VersionChange) {
        ASSERT(transaction.get() == m_runningVersionChangeTransaction.get());
        m_runningVersionChangeTransaction.clear();
    }
}

void IDBDatabaseBackend::transactionFinishedAndAbortFired(IDBTransactionBackend* rawTransaction)
{
    RefPtr<IDBTransactionBackend> transaction = rawTransaction;
    if (transaction->mode() == IndexedDB::TransactionMode::VersionChange) {
        // If this was an open-with-version call, there will be a "second
        // half" open call waiting for us in processPendingCalls.
        // FIXME: When we no longer support setVersion, assert such a thing.
        if (m_pendingSecondHalfOpen) {
            m_pendingSecondHalfOpen->callbacks()->onError(IDBDatabaseError::create(IDBDatabaseException::AbortError, "Version change transaction was aborted in upgradeneeded event handler."));
            m_pendingSecondHalfOpen = nullptr;
        }
        processPendingCalls();
    }
}

void IDBDatabaseBackend::transactionFinishedAndCompleteFired(IDBTransactionBackend* rawTransaction)
{
    RefPtr<IDBTransactionBackend> transaction = rawTransaction;
    if (transaction->mode() == IndexedDB::TransactionMode::VersionChange)
        processPendingCalls();
}

size_t IDBDatabaseBackend::connectionCount()
{
    // This does not include pending open calls, as those should not block version changes and deletes.
    return m_databaseCallbacksSet.size();
}

void IDBDatabaseBackend::processPendingCalls()
{
    // processPendingCalls() will be called again after openInternalAsync() completes.
    if (!m_didOpenInternal)
        return;

    if (m_pendingSecondHalfOpen) {
        ASSERT(m_pendingSecondHalfOpen->version() == m_metadata.version);
        ASSERT(m_metadata.id != InvalidId);
        m_pendingSecondHalfOpen->callbacks()->onSuccess(this, this->metadata());
        m_pendingSecondHalfOpen = nullptr;
        // Fall through when complete, as pending deletes may be (partially) unblocked.
    }

    // Note that this check is only an optimization to reduce queue-churn and
    // not necessary for correctness; deleteDatabase and openConnection will
    // requeue their calls if this condition is true.
    if (m_runningVersionChangeTransaction)
        return;

    if (!m_pendingDeleteCalls.isEmpty() && isDeleteDatabaseBlocked())
        return;
    while (!m_pendingDeleteCalls.isEmpty()) {
        std::unique_ptr<IDBPendingDeleteCall> pendingDeleteCall = m_pendingDeleteCalls.takeFirst();
        m_deleteCallbacksWaitingCompletion.add(pendingDeleteCall->callbacks());
        deleteDatabaseAsync(pendingDeleteCall->callbacks());
    }

    // deleteDatabaseAsync should never re-queue calls.
    ASSERT(m_pendingDeleteCalls.isEmpty());

    // If there are any database deletions waiting for completion, we're done for now.
    // Further callbacks will be handled in a future call to processPendingCalls().
    if (!m_deleteCallbacksWaitingCompletion.isEmpty())
        return;

    if (m_runningVersionChangeTransaction)
        return;

    processPendingOpenCalls(true);
}

void IDBDatabaseBackend::processPendingOpenCalls(bool success)
{
    // Open calls can be requeued if an open call started a version change transaction or deletes the database.
    Deque<std::unique_ptr<IDBPendingOpenCall>> pendingOpenCalls;
    m_pendingOpenCalls.swap(pendingOpenCalls);

    while (!pendingOpenCalls.isEmpty()) {
        std::unique_ptr<IDBPendingOpenCall> pendingOpenCall = pendingOpenCalls.takeFirst();
        if (success) {
            if (m_metadata.id == InvalidId) {
                // This database was deleted then quickly re-opened.
                // openInternalAsync() will recreate it in the backing store and then resume processing pending callbacks.
                pendingOpenCalls.prepend(WTF::move(pendingOpenCall));
                pendingOpenCalls.swap(m_pendingOpenCalls);

                openInternalAsync();
                return;
            }
            openConnectionInternal(pendingOpenCall->callbacks(), pendingOpenCall->databaseCallbacks(), pendingOpenCall->transactionId(), pendingOpenCall->version());
        } else {
            String message;
            if (pendingOpenCall->version() == IDBDatabaseMetadata::NoIntVersion)
                message = "Internal error opening database with no version specified.";
            else
                message = String::format("Internal error opening database with version %llu", static_cast<unsigned long long>(pendingOpenCall->version()));
            pendingOpenCall->callbacks()->onError(IDBDatabaseError::create(IDBDatabaseException::UnknownError, message));
        }
    }
}

void IDBDatabaseBackend::createTransaction(int64_t transactionID, PassRefPtr<IDBDatabaseCallbacks> callbacks, const Vector<int64_t>& objectStoreIDs, IndexedDB::TransactionMode mode)
{
    RefPtr<IDBTransactionBackend> transaction = IDBTransactionBackend::create(this, transactionID, callbacks, objectStoreIDs, mode);

    ASSERT(!m_transactions.contains(transactionID));
    m_transactions.add(transactionID, transaction.get());
}

void IDBDatabaseBackend::openConnection(PassRefPtr<IDBCallbacks> prpCallbacks, PassRefPtr<IDBDatabaseCallbacks> prpDatabaseCallbacks, int64_t transactionId, uint64_t version)
{
    RefPtr<IDBCallbacks> callbacks = prpCallbacks;
    RefPtr<IDBDatabaseCallbacks> databaseCallbacks = prpDatabaseCallbacks;

    m_pendingOpenCalls.append(std::make_unique<IDBPendingOpenCall>(*callbacks, *databaseCallbacks, transactionId, version));

    processPendingCalls();
}

void IDBDatabaseBackend::openConnectionInternal(PassRefPtr<IDBCallbacks> prpCallbacks, PassRefPtr<IDBDatabaseCallbacks> prpDatabaseCallbacks, int64_t transactionId, uint64_t version)
{
    ASSERT(m_pendingDeleteCalls.isEmpty());
    ASSERT(!m_runningVersionChangeTransaction);

    RefPtr<IDBCallbacks> callbacks = prpCallbacks;
    RefPtr<IDBDatabaseCallbacks> databaseCallbacks = prpDatabaseCallbacks;

    // We infer that the database didn't exist from its lack of version.
    bool isNewDatabase = m_metadata.version == IDBDatabaseMetadata::NoIntVersion;

    if (version == IDBDatabaseMetadata::DefaultIntVersion && !isNewDatabase) {
        m_databaseCallbacksSet.add(databaseCallbacks);
        callbacks->onSuccess(this, this->metadata());
        return;
    }

    if (isNewDatabase && version == IDBDatabaseMetadata::DefaultIntVersion) {
        // Spec says: If no version is specified and no database exists, set database version to 1.
        version = 1;
    }

    if (version > m_metadata.version || m_metadata.version == IDBDatabaseMetadata::NoIntVersion) {
        runIntVersionChangeTransaction(callbacks, databaseCallbacks, transactionId, version);
        return;
    }

    if (version < m_metadata.version && m_metadata.version != IDBDatabaseMetadata::NoIntVersion) {
        callbacks->onError(IDBDatabaseError::create(IDBDatabaseException::VersionError, String::format("The requested version (%llu) is less than the existing version (%llu).", static_cast<unsigned long long>(version), static_cast<unsigned long long>(m_metadata.version))));
        return;
    }

    ASSERT(version == m_metadata.version);
    m_databaseCallbacksSet.add(databaseCallbacks);
    callbacks->onSuccess(this, this->metadata());
}

void IDBDatabaseBackend::runIntVersionChangeTransaction(PassRefPtr<IDBCallbacks> prpCallbacks, PassRefPtr<IDBDatabaseCallbacks> prpDatabaseCallbacks, int64_t transactionId, int64_t requestedVersion)
{
    RefPtr<IDBCallbacks> callbacks = prpCallbacks;
    RefPtr<IDBDatabaseCallbacks> databaseCallbacks = prpDatabaseCallbacks;
    ASSERT(callbacks);
    for (DatabaseCallbacksSet::const_iterator it = m_databaseCallbacksSet.begin(); it != m_databaseCallbacksSet.end(); ++it) {
        // Front end ensures the event is not fired at connections that have closePending set.
        if (*it != databaseCallbacks)
            (*it)->onVersionChange(m_metadata.version, requestedVersion, IndexedDB::VersionNullness::Null);
    }
    // The spec dictates we wait until all the version change events are
    // delivered and then check m_databaseCallbacks.empty() before proceeding
    // or firing a blocked event, but instead we should be consistent with how
    // the old setVersion (incorrectly) did it.
    // FIXME: Remove the call to onBlocked and instead wait until the frontend
    // tells us that all the blocked events have been delivered. See
    // https://bugs.webkit.org/show_bug.cgi?id=71130
    if (connectionCount())
        callbacks->onBlocked(m_metadata.version);
    // FIXME: Add test for m_runningVersionChangeTransaction.
    if (m_runningVersionChangeTransaction || connectionCount()) {
        m_pendingOpenCalls.append(std::make_unique<IDBPendingOpenCall>(*callbacks, *databaseCallbacks, transactionId, requestedVersion));
        return;
    }

    Vector<int64_t> objectStoreIds;
    createTransaction(transactionId, databaseCallbacks, objectStoreIds, IndexedDB::TransactionMode::VersionChange);
    RefPtr<IDBTransactionBackend> transaction = m_transactions.get(transactionId);

    transaction->scheduleVersionChangeOperation(requestedVersion, callbacks, databaseCallbacks, m_metadata);

    ASSERT(!m_pendingSecondHalfOpen);
    m_databaseCallbacksSet.add(databaseCallbacks);
}

void IDBDatabaseBackend::deleteDatabase(PassRefPtr<IDBCallbacks> prpCallbacks)
{
    RefPtr<IDBCallbacks> callbacks = prpCallbacks;
    if (isDeleteDatabaseBlocked()) {
        for (DatabaseCallbacksSet::const_iterator it = m_databaseCallbacksSet.begin(); it != m_databaseCallbacksSet.end(); ++it) {
            // Front end ensures the event is not fired at connections that have closePending set.
            (*it)->onVersionChange(m_metadata.version, 0, IndexedDB::VersionNullness::Null);
        }
        // FIXME: Only fire onBlocked if there are open connections after the
        // VersionChangeEvents are received, not just set up to fire.
        // https://bugs.webkit.org/show_bug.cgi?id=71130
        callbacks->onBlocked(m_metadata.version);
        m_pendingDeleteCalls.append(std::make_unique<IDBPendingDeleteCall>(callbacks.release()));
        return;
    }
    deleteDatabaseAsync(callbacks.release());
}

bool IDBDatabaseBackend::isDeleteDatabaseBlocked()
{
    return connectionCount();
}

void IDBDatabaseBackend::deleteDatabaseAsync(PassRefPtr<IDBCallbacks> prpCallbacks)
{
    ASSERT(!isDeleteDatabaseBlocked());

    RefPtr<IDBDatabaseBackend> self(this);
    RefPtr<IDBCallbacks> callbacks = prpCallbacks;
    m_serverConnection->deleteDatabase(m_metadata.name, [self, callbacks](bool success) {
        self->m_deleteCallbacksWaitingCompletion.remove(callbacks);

        // If this IDBDatabaseBackend was closed while waiting for deleteDatabase to complete, no point in performing any callbacks.
        if (!self->m_serverConnection->isClosed())
            return;

        if (success) {
            self->m_metadata.id = InvalidId;
            self->m_metadata.version = IDBDatabaseMetadata::NoIntVersion;
            self->m_metadata.objectStores.clear();
            callbacks->onSuccess();
        } else
            callbacks->onError(IDBDatabaseError::create(IDBDatabaseException::UnknownError, "Internal error deleting database."));

        self->processPendingCalls();
    });
}

void IDBDatabaseBackend::close(PassRefPtr<IDBDatabaseCallbacks> prpCallbacks)
{
    RefPtr<IDBDatabaseCallbacks> callbacks = prpCallbacks;
    ASSERT(m_databaseCallbacksSet.contains(callbacks));

    m_databaseCallbacksSet.remove(callbacks);
    if (m_pendingSecondHalfOpen && m_pendingSecondHalfOpen->databaseCallbacks() == callbacks) {
        m_pendingSecondHalfOpen->callbacks()->onError(IDBDatabaseError::create(IDBDatabaseException::AbortError, "The connection was closed."));
        m_pendingSecondHalfOpen = nullptr;
    }

    if (connectionCount() > 1)
        return;

    // processPendingCalls allows the inspector to process a pending open call
    // and call close, reentering IDBDatabaseBackend::close. Then the
    // backend would be removed both by the inspector closing its connection, and
    // by the connection that first called close.
    // To avoid that situation, don't proceed in case of reentrancy.
    if (m_closingConnection)
        return;
    TemporaryChange<bool> closingConnection(m_closingConnection, true);
    processPendingCalls();

    // FIXME: Add a test for the m_pendingOpenCalls cases below.
    if (!connectionCount() && !m_pendingOpenCalls.size() && !m_pendingDeleteCalls.size()) {
        TransactionMap transactions(m_transactions);
        RefPtr<IDBDatabaseError> error = IDBDatabaseError::create(IDBDatabaseException::UnknownError, "Connection is closing.");
        for (TransactionMap::const_iterator::Values it = transactions.values().begin(), end = transactions.values().end(); it != end; ++it)
            (*it)->abort(error);

        ASSERT(m_transactions.isEmpty());

        m_serverConnection->close();

        // This check should only be false in unit tests.
        ASSERT(m_factory);
        if (m_factory)
            m_factory->removeIDBDatabaseBackend(m_identifier);
    }
}

} // namespace WebCore

#endif // ENABLE(INDEXED_DATABASE)