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      1 /*
      2  * Copyright (C) 2011 Google Inc. All rights reserved.
      3  * Copyright (C) 2013 Apple Inc. All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  *
      9  * 1.  Redistributions of source code must retain the above copyright
     10  *     notice, this list of conditions and the following disclaimer.
     11  * 2.  Redistributions in binary form must reproduce the above copyright
     12  *     notice, this list of conditions and the following disclaimer in the
     13  *     documentation and/or other materials provided with the distribution.
     14  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
     15  *     its contributors may be used to endorse or promote products derived
     16  *     from this software without specific prior written permission.
     17  *
     18  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
     19  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     21  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
     22  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     23  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     24  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
     25  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     28  */
     29 
     30 #include "config.h"
     31 #include "modules/webdatabase/DatabaseBackendBase.h"
     32 
     33 #include "core/dom/ExceptionCode.h"
     34 #include "platform/Logging.h"
     35 #include "modules/webdatabase/DatabaseAuthorizer.h"
     36 #include "modules/webdatabase/DatabaseBase.h"
     37 #include "modules/webdatabase/DatabaseContext.h"
     38 #include "modules/webdatabase/DatabaseManager.h"
     39 #include "modules/webdatabase/DatabaseTracker.h"
     40 #include "modules/webdatabase/sqlite/SQLiteStatement.h"
     41 #include "modules/webdatabase/sqlite/SQLiteTransaction.h"
     42 #include "platform/weborigin/DatabaseIdentifier.h"
     43 #include "public/platform/Platform.h"
     44 #include "public/platform/WebDatabaseObserver.h"
     45 #include "wtf/HashMap.h"
     46 #include "wtf/HashSet.h"
     47 #include "wtf/PassRefPtr.h"
     48 #include "wtf/StdLibExtras.h"
     49 #include "wtf/text/CString.h"
     50 #include "wtf/text/StringHash.h"
     51 
     52 // Registering "opened" databases with the DatabaseTracker
     53 // =======================================================
     54 // The DatabaseTracker maintains a list of databases that have been
     55 // "opened" so that the client can call interrupt or delete on every database
     56 // associated with a DatabaseContext.
     57 //
     58 // We will only call DatabaseTracker::addOpenDatabase() to add the database
     59 // to the tracker as opened when we've succeeded in opening the database,
     60 // and will set m_opened to true. Similarly, we only call
     61 // DatabaseTracker::removeOpenDatabase() to remove the database from the
     62 // tracker when we set m_opened to false in closeDatabase(). This sets up
     63 // a simple symmetry between open and close operations, and a direct
     64 // correlation to adding and removing databases from the tracker's list,
     65 // thus ensuring that we have a correct list for the interrupt and
     66 // delete operations to work on.
     67 //
     68 // The only databases instances not tracked by the tracker's open database
     69 // list are the ones that have not been added yet, or the ones that we
     70 // attempted an open on but failed to. Such instances only exist in the
     71 // DatabaseServer's factory methods for creating database backends.
     72 //
     73 // The factory methods will either call openAndVerifyVersion() or
     74 // performOpenAndVerify(). These methods will add the newly instantiated
     75 // database backend if they succeed in opening the requested database.
     76 // In the case of failure to open the database, the factory methods will
     77 // simply discard the newly instantiated database backend when they return.
     78 // The ref counting mechanims will automatically destruct the un-added
     79 // (and un-returned) databases instances.
     80 
     81 namespace WebCore {
     82 
     83 static const char versionKey[] = "WebKitDatabaseVersionKey";
     84 static const char infoTableName[] = "__WebKitDatabaseInfoTable__";
     85 
     86 static String formatErrorMessage(const char* message, int sqliteErrorCode, const char* sqliteErrorMessage)
     87 {
     88     return String::format("%s (%d %s)", message, sqliteErrorCode, sqliteErrorMessage);
     89 }
     90 
     91 static bool retrieveTextResultFromDatabase(SQLiteDatabase& db, const String& query, String& resultString)
     92 {
     93     SQLiteStatement statement(db, query);
     94     int result = statement.prepare();
     95 
     96     if (result != SQLResultOk) {
     97         WTF_LOG_ERROR("Error (%i) preparing statement to read text result from database (%s)", result, query.ascii().data());
     98         return false;
     99     }
    100 
    101     result = statement.step();
    102     if (result == SQLResultRow) {
    103         resultString = statement.getColumnText(0);
    104         return true;
    105     }
    106     if (result == SQLResultDone) {
    107         resultString = String();
    108         return true;
    109     }
    110 
    111     WTF_LOG_ERROR("Error (%i) reading text result from database (%s)", result, query.ascii().data());
    112     return false;
    113 }
    114 
    115 static bool setTextValueInDatabase(SQLiteDatabase& db, const String& query, const String& value)
    116 {
    117     SQLiteStatement statement(db, query);
    118     int result = statement.prepare();
    119 
    120     if (result != SQLResultOk) {
    121         WTF_LOG_ERROR("Failed to prepare statement to set value in database (%s)", query.ascii().data());
    122         return false;
    123     }
    124 
    125     statement.bindText(1, value);
    126 
    127     result = statement.step();
    128     if (result != SQLResultDone) {
    129         WTF_LOG_ERROR("Failed to step statement to set value in database (%s)", query.ascii().data());
    130         return false;
    131     }
    132 
    133     return true;
    134 }
    135 
    136 // FIXME: move all guid-related functions to a DatabaseVersionTracker class.
    137 static Mutex& guidMutex()
    138 {
    139     AtomicallyInitializedStatic(Mutex&, mutex = *new Mutex);
    140     return mutex;
    141 }
    142 
    143 typedef HashMap<DatabaseGuid, String> GuidVersionMap;
    144 static GuidVersionMap& guidToVersionMap()
    145 {
    146     // Ensure the the mutex is locked.
    147     ASSERT(!guidMutex().tryLock());
    148     DEFINE_STATIC_LOCAL(GuidVersionMap, map, ());
    149     return map;
    150 }
    151 
    152 // NOTE: Caller must lock guidMutex().
    153 static inline void updateGuidVersionMap(DatabaseGuid guid, String newVersion)
    154 {
    155     // Ensure the the mutex is locked.
    156     ASSERT(!guidMutex().tryLock());
    157 
    158     // Note: It is not safe to put an empty string into the guidToVersionMap() map.
    159     // That's because the map is cross-thread, but empty strings are per-thread.
    160     // The copy() function makes a version of the string you can use on the current
    161     // thread, but we need a string we can keep in a cross-thread data structure.
    162     // FIXME: This is a quite-awkward restriction to have to program with.
    163 
    164     // Map null string to empty string (see comment above).
    165     guidToVersionMap().set(guid, newVersion.isEmpty() ? String() : newVersion.isolatedCopy());
    166 }
    167 
    168 typedef HashMap<DatabaseGuid, HashSet<DatabaseBackendBase*>*> GuidDatabaseMap;
    169 static GuidDatabaseMap& guidToDatabaseMap()
    170 {
    171     // Ensure the the mutex is locked.
    172     ASSERT(!guidMutex().tryLock());
    173     DEFINE_STATIC_LOCAL(GuidDatabaseMap, map, ());
    174     return map;
    175 }
    176 
    177 static DatabaseGuid guidForOriginAndName(const String& origin, const String& name)
    178 {
    179     // Ensure the the mutex is locked.
    180     ASSERT(!guidMutex().tryLock());
    181 
    182     String stringID = origin + "/" + name;
    183 
    184     typedef HashMap<String, int> IDGuidMap;
    185     DEFINE_STATIC_LOCAL(IDGuidMap, stringIdentifierToGUIDMap, ());
    186     DatabaseGuid guid = stringIdentifierToGUIDMap.get(stringID);
    187     if (!guid) {
    188         static int currentNewGUID = 1;
    189         guid = currentNewGUID++;
    190         stringIdentifierToGUIDMap.set(stringID, guid);
    191     }
    192 
    193     return guid;
    194 }
    195 
    196 // static
    197 const char* DatabaseBackendBase::databaseInfoTableName()
    198 {
    199     return infoTableName;
    200 }
    201 
    202 DatabaseBackendBase::DatabaseBackendBase(PassRefPtr<DatabaseContext> databaseContext, const String& name,
    203     const String& expectedVersion, const String& displayName, unsigned long estimatedSize, DatabaseType databaseType)
    204     : m_databaseContext(databaseContext)
    205     , m_name(name.isolatedCopy())
    206     , m_expectedVersion(expectedVersion.isolatedCopy())
    207     , m_displayName(displayName.isolatedCopy())
    208     , m_estimatedSize(estimatedSize)
    209     , m_guid(0)
    210     , m_opened(false)
    211     , m_new(false)
    212     , m_isSyncDatabase(databaseType == DatabaseType::Sync)
    213 {
    214     m_contextThreadSecurityOrigin = m_databaseContext->securityOrigin()->isolatedCopy();
    215 
    216     m_databaseAuthorizer = DatabaseAuthorizer::create(infoTableName);
    217 
    218     if (m_name.isNull())
    219         m_name = "";
    220 
    221     {
    222         MutexLocker locker(guidMutex());
    223         m_guid = guidForOriginAndName(securityOrigin()->toString(), name);
    224         HashSet<DatabaseBackendBase*>* hashSet = guidToDatabaseMap().get(m_guid);
    225         if (!hashSet) {
    226             hashSet = new HashSet<DatabaseBackendBase*>;
    227             guidToDatabaseMap().set(m_guid, hashSet);
    228         }
    229 
    230         hashSet->add(this);
    231     }
    232 
    233     m_filename = DatabaseManager::manager().fullPathForDatabase(securityOrigin(), m_name);
    234 }
    235 
    236 DatabaseBackendBase::~DatabaseBackendBase()
    237 {
    238     // SQLite is "multi-thread safe", but each database handle can only be used
    239     // on a single thread at a time.
    240     //
    241     // For DatabaseBackend, we open the SQLite database on the DatabaseThread,
    242     // and hence we should also close it on that same thread. This means that the
    243     // SQLite database need to be closed by another mechanism (see
    244     // DatabaseContext::stopDatabases()). By the time we get here, the SQLite
    245     // database should have already been closed.
    246 
    247     ASSERT(!m_opened);
    248 }
    249 
    250 void DatabaseBackendBase::closeDatabase()
    251 {
    252     if (!m_opened)
    253         return;
    254 
    255     m_sqliteDatabase.close();
    256     m_opened = false;
    257     // See comment at the top this file regarding calling removeOpenDatabase().
    258     DatabaseTracker::tracker().removeOpenDatabase(this);
    259     {
    260         MutexLocker locker(guidMutex());
    261 
    262         HashSet<DatabaseBackendBase*>* hashSet = guidToDatabaseMap().get(m_guid);
    263         ASSERT(hashSet);
    264         ASSERT(hashSet->contains(this));
    265         hashSet->remove(this);
    266         if (hashSet->isEmpty()) {
    267             guidToDatabaseMap().remove(m_guid);
    268             delete hashSet;
    269             guidToVersionMap().remove(m_guid);
    270         }
    271     }
    272 }
    273 
    274 String DatabaseBackendBase::version() const
    275 {
    276     // Note: In multi-process browsers the cached value may be accurate, but we cannot read the
    277     // actual version from the database without potentially inducing a deadlock.
    278     // FIXME: Add an async version getter to the DatabaseAPI.
    279     return getCachedVersion();
    280 }
    281 
    282 class DoneCreatingDatabaseOnExitCaller {
    283 public:
    284     DoneCreatingDatabaseOnExitCaller(DatabaseBackendBase* database)
    285         : m_database(database)
    286         , m_openSucceeded(false)
    287     {
    288     }
    289     ~DoneCreatingDatabaseOnExitCaller()
    290     {
    291         if (!m_openSucceeded)
    292             DatabaseTracker::tracker().failedToOpenDatabase(m_database);
    293     }
    294 
    295     void setOpenSucceeded() { m_openSucceeded = true; }
    296 
    297 private:
    298     DatabaseBackendBase* m_database;
    299     bool m_openSucceeded;
    300 };
    301 
    302 bool DatabaseBackendBase::performOpenAndVerify(bool shouldSetVersionInNewDatabase, DatabaseError& error, String& errorMessage)
    303 {
    304     DoneCreatingDatabaseOnExitCaller onExitCaller(this);
    305     ASSERT(errorMessage.isEmpty());
    306     ASSERT(error == DatabaseError::None); // Better not have any errors already.
    307     error = DatabaseError::InvalidDatabaseState; // Presumed failure. We'll clear it if we succeed below.
    308 
    309     const int maxSqliteBusyWaitTime = 30000;
    310 
    311     if (!m_sqliteDatabase.open(m_filename, true)) {
    312         reportOpenDatabaseResult(1, InvalidStateError, m_sqliteDatabase.lastError());
    313         errorMessage = formatErrorMessage("unable to open database", m_sqliteDatabase.lastError(), m_sqliteDatabase.lastErrorMsg());
    314         return false;
    315     }
    316     if (!m_sqliteDatabase.turnOnIncrementalAutoVacuum())
    317         WTF_LOG_ERROR("Unable to turn on incremental auto-vacuum (%d %s)", m_sqliteDatabase.lastError(), m_sqliteDatabase.lastErrorMsg());
    318 
    319     m_sqliteDatabase.setBusyTimeout(maxSqliteBusyWaitTime);
    320 
    321     String currentVersion;
    322     {
    323         MutexLocker locker(guidMutex());
    324 
    325         GuidVersionMap::iterator entry = guidToVersionMap().find(m_guid);
    326         if (entry != guidToVersionMap().end()) {
    327             // Map null string to empty string (see updateGuidVersionMap()).
    328             currentVersion = entry->value.isNull() ? emptyString() : entry->value.isolatedCopy();
    329             WTF_LOG(StorageAPI, "Current cached version for guid %i is %s", m_guid, currentVersion.ascii().data());
    330 
    331             // Note: In multi-process browsers the cached value may be inaccurate, but
    332             // we cannot read the actual version from the database without potentially
    333             // inducing a form of deadlock, a busytimeout error when trying to
    334             // access the database. So we'll use the cached value if we're unable to read
    335             // the value from the database file without waiting.
    336             // FIXME: Add an async openDatabase method to the DatabaseAPI.
    337             const int noSqliteBusyWaitTime = 0;
    338             m_sqliteDatabase.setBusyTimeout(noSqliteBusyWaitTime);
    339             String versionFromDatabase;
    340             if (getVersionFromDatabase(versionFromDatabase, false)) {
    341                 currentVersion = versionFromDatabase;
    342                 updateGuidVersionMap(m_guid, currentVersion);
    343             }
    344             m_sqliteDatabase.setBusyTimeout(maxSqliteBusyWaitTime);
    345         } else {
    346             WTF_LOG(StorageAPI, "No cached version for guid %i", m_guid);
    347 
    348             SQLiteTransaction transaction(m_sqliteDatabase);
    349             transaction.begin();
    350             if (!transaction.inProgress()) {
    351                 reportOpenDatabaseResult(2, InvalidStateError, m_sqliteDatabase.lastError());
    352                 errorMessage = formatErrorMessage("unable to open database, failed to start transaction", m_sqliteDatabase.lastError(), m_sqliteDatabase.lastErrorMsg());
    353                 m_sqliteDatabase.close();
    354                 return false;
    355             }
    356 
    357             String tableName(infoTableName);
    358             if (!m_sqliteDatabase.tableExists(tableName)) {
    359                 m_new = true;
    360 
    361                 if (!m_sqliteDatabase.executeCommand("CREATE TABLE " + tableName + " (key TEXT NOT NULL ON CONFLICT FAIL UNIQUE ON CONFLICT REPLACE,value TEXT NOT NULL ON CONFLICT FAIL);")) {
    362                     reportOpenDatabaseResult(3, InvalidStateError, m_sqliteDatabase.lastError());
    363                     errorMessage = formatErrorMessage("unable to open database, failed to create 'info' table", m_sqliteDatabase.lastError(), m_sqliteDatabase.lastErrorMsg());
    364                     transaction.rollback();
    365                     m_sqliteDatabase.close();
    366                     return false;
    367                 }
    368             } else if (!getVersionFromDatabase(currentVersion, false)) {
    369                 reportOpenDatabaseResult(4, InvalidStateError, m_sqliteDatabase.lastError());
    370                 errorMessage = formatErrorMessage("unable to open database, failed to read current version", m_sqliteDatabase.lastError(), m_sqliteDatabase.lastErrorMsg());
    371                 transaction.rollback();
    372                 m_sqliteDatabase.close();
    373                 return false;
    374             }
    375 
    376             if (currentVersion.length()) {
    377                 WTF_LOG(StorageAPI, "Retrieved current version %s from database %s", currentVersion.ascii().data(), databaseDebugName().ascii().data());
    378             } else if (!m_new || shouldSetVersionInNewDatabase) {
    379                 WTF_LOG(StorageAPI, "Setting version %s in database %s that was just created", m_expectedVersion.ascii().data(), databaseDebugName().ascii().data());
    380                 if (!setVersionInDatabase(m_expectedVersion, false)) {
    381                     reportOpenDatabaseResult(5, InvalidStateError, m_sqliteDatabase.lastError());
    382                     errorMessage = formatErrorMessage("unable to open database, failed to write current version", m_sqliteDatabase.lastError(), m_sqliteDatabase.lastErrorMsg());
    383                     transaction.rollback();
    384                     m_sqliteDatabase.close();
    385                     return false;
    386                 }
    387                 currentVersion = m_expectedVersion;
    388             }
    389             updateGuidVersionMap(m_guid, currentVersion);
    390             transaction.commit();
    391         }
    392     }
    393 
    394     if (currentVersion.isNull()) {
    395         WTF_LOG(StorageAPI, "Database %s does not have its version set", databaseDebugName().ascii().data());
    396         currentVersion = "";
    397     }
    398 
    399     // If the expected version isn't the empty string, ensure that the current database version we have matches that version. Otherwise, set an exception.
    400     // If the expected version is the empty string, then we always return with whatever version of the database we have.
    401     if ((!m_new || shouldSetVersionInNewDatabase) && m_expectedVersion.length() && m_expectedVersion != currentVersion) {
    402         reportOpenDatabaseResult(6, InvalidStateError, 0);
    403         errorMessage = "unable to open database, version mismatch, '" + m_expectedVersion + "' does not match the currentVersion of '" + currentVersion + "'";
    404         m_sqliteDatabase.close();
    405         return false;
    406     }
    407 
    408     ASSERT(m_databaseAuthorizer);
    409     m_sqliteDatabase.setAuthorizer(m_databaseAuthorizer);
    410 
    411     // See comment at the top this file regarding calling addOpenDatabase().
    412     DatabaseTracker::tracker().addOpenDatabase(this);
    413     m_opened = true;
    414 
    415     // Declare success:
    416     error = DatabaseError::None; // Clear the presumed error from above.
    417     onExitCaller.setOpenSucceeded();
    418 
    419     if (m_new && !shouldSetVersionInNewDatabase)
    420         m_expectedVersion = ""; // The caller provided a creationCallback which will set the expected version.
    421 
    422     reportOpenDatabaseResult(0, -1, 0); // OK
    423     return true;
    424 }
    425 
    426 SecurityOrigin* DatabaseBackendBase::securityOrigin() const
    427 {
    428     return m_contextThreadSecurityOrigin.get();
    429 }
    430 
    431 String DatabaseBackendBase::stringIdentifier() const
    432 {
    433     // Return a deep copy for ref counting thread safety
    434     return m_name.isolatedCopy();
    435 }
    436 
    437 String DatabaseBackendBase::displayName() const
    438 {
    439     // Return a deep copy for ref counting thread safety
    440     return m_displayName.isolatedCopy();
    441 }
    442 
    443 unsigned long DatabaseBackendBase::estimatedSize() const
    444 {
    445     return m_estimatedSize;
    446 }
    447 
    448 String DatabaseBackendBase::fileName() const
    449 {
    450     // Return a deep copy for ref counting thread safety
    451     return m_filename.isolatedCopy();
    452 }
    453 
    454 DatabaseDetails DatabaseBackendBase::details() const
    455 {
    456     return DatabaseDetails(stringIdentifier(), displayName(), estimatedSize(), 0);
    457 }
    458 
    459 bool DatabaseBackendBase::getVersionFromDatabase(String& version, bool shouldCacheVersion)
    460 {
    461     String query(String("SELECT value FROM ") + infoTableName +  " WHERE key = '" + versionKey + "';");
    462 
    463     m_databaseAuthorizer->disable();
    464 
    465     bool result = retrieveTextResultFromDatabase(m_sqliteDatabase, query, version);
    466     if (result) {
    467         if (shouldCacheVersion)
    468             setCachedVersion(version);
    469     } else
    470         WTF_LOG_ERROR("Failed to retrieve version from database %s", databaseDebugName().ascii().data());
    471 
    472     m_databaseAuthorizer->enable();
    473 
    474     return result;
    475 }
    476 
    477 bool DatabaseBackendBase::setVersionInDatabase(const String& version, bool shouldCacheVersion)
    478 {
    479     // The INSERT will replace an existing entry for the database with the new version number, due to the UNIQUE ON CONFLICT REPLACE
    480     // clause in the CREATE statement (see Database::performOpenAndVerify()).
    481     String query(String("INSERT INTO ") + infoTableName +  " (key, value) VALUES ('" + versionKey + "', ?);");
    482 
    483     m_databaseAuthorizer->disable();
    484 
    485     bool result = setTextValueInDatabase(m_sqliteDatabase, query, version);
    486     if (result) {
    487         if (shouldCacheVersion)
    488             setCachedVersion(version);
    489     } else
    490         WTF_LOG_ERROR("Failed to set version %s in database (%s)", version.ascii().data(), query.ascii().data());
    491 
    492     m_databaseAuthorizer->enable();
    493 
    494     return result;
    495 }
    496 
    497 void DatabaseBackendBase::setExpectedVersion(const String& version)
    498 {
    499     m_expectedVersion = version.isolatedCopy();
    500 }
    501 
    502 String DatabaseBackendBase::getCachedVersion() const
    503 {
    504     MutexLocker locker(guidMutex());
    505     return guidToVersionMap().get(m_guid).isolatedCopy();
    506 }
    507 
    508 void DatabaseBackendBase::setCachedVersion(const String& actualVersion)
    509 {
    510     // Update the in memory database version map.
    511     MutexLocker locker(guidMutex());
    512     updateGuidVersionMap(m_guid, actualVersion);
    513 }
    514 
    515 bool DatabaseBackendBase::getActualVersionForTransaction(String &actualVersion)
    516 {
    517     ASSERT(m_sqliteDatabase.transactionInProgress());
    518     // Note: In multi-process browsers the cached value may be inaccurate.
    519     // So we retrieve the value from the database and update the cached value here.
    520     return getVersionFromDatabase(actualVersion, true);
    521 }
    522 
    523 void DatabaseBackendBase::disableAuthorizer()
    524 {
    525     ASSERT(m_databaseAuthorizer);
    526     m_databaseAuthorizer->disable();
    527 }
    528 
    529 void DatabaseBackendBase::enableAuthorizer()
    530 {
    531     ASSERT(m_databaseAuthorizer);
    532     m_databaseAuthorizer->enable();
    533 }
    534 
    535 void DatabaseBackendBase::setAuthorizerReadOnly()
    536 {
    537     ASSERT(m_databaseAuthorizer);
    538     m_databaseAuthorizer->setReadOnly();
    539 }
    540 
    541 void DatabaseBackendBase::setAuthorizerPermissions(int permissions)
    542 {
    543     ASSERT(m_databaseAuthorizer);
    544     m_databaseAuthorizer->setPermissions(permissions);
    545 }
    546 
    547 bool DatabaseBackendBase::lastActionChangedDatabase()
    548 {
    549     ASSERT(m_databaseAuthorizer);
    550     return m_databaseAuthorizer->lastActionChangedDatabase();
    551 }
    552 
    553 bool DatabaseBackendBase::lastActionWasInsert()
    554 {
    555     ASSERT(m_databaseAuthorizer);
    556     return m_databaseAuthorizer->lastActionWasInsert();
    557 }
    558 
    559 void DatabaseBackendBase::resetDeletes()
    560 {
    561     ASSERT(m_databaseAuthorizer);
    562     m_databaseAuthorizer->resetDeletes();
    563 }
    564 
    565 bool DatabaseBackendBase::hadDeletes()
    566 {
    567     ASSERT(m_databaseAuthorizer);
    568     return m_databaseAuthorizer->hadDeletes();
    569 }
    570 
    571 void DatabaseBackendBase::resetAuthorizer()
    572 {
    573     if (m_databaseAuthorizer)
    574         m_databaseAuthorizer->reset();
    575 }
    576 
    577 unsigned long long DatabaseBackendBase::maximumSize() const
    578 {
    579     return DatabaseTracker::tracker().getMaxSizeForDatabase(this);
    580 }
    581 
    582 void DatabaseBackendBase::incrementalVacuumIfNeeded()
    583 {
    584     int64_t freeSpaceSize = m_sqliteDatabase.freeSpaceSize();
    585     int64_t totalSize = m_sqliteDatabase.totalSize();
    586     if (totalSize <= 10 * freeSpaceSize) {
    587         int result = m_sqliteDatabase.runIncrementalVacuumCommand();
    588         reportVacuumDatabaseResult(result);
    589         if (result != SQLResultOk)
    590             m_frontend->logErrorMessage(formatErrorMessage("error vacuuming database", result, m_sqliteDatabase.lastErrorMsg()));
    591     }
    592 }
    593 
    594 void DatabaseBackendBase::interrupt()
    595 {
    596     m_sqliteDatabase.interrupt();
    597 }
    598 
    599 bool DatabaseBackendBase::isInterrupted()
    600 {
    601     MutexLocker locker(m_sqliteDatabase.databaseMutex());
    602     return m_sqliteDatabase.isInterrupted();
    603 }
    604 
    605 // These are used to generate histograms of errors seen with websql.
    606 // See about:histograms in chromium.
    607 void DatabaseBackendBase::reportOpenDatabaseResult(int errorSite, int webSqlErrorCode, int sqliteErrorCode)
    608 {
    609     if (blink::Platform::current()->databaseObserver()) {
    610         blink::Platform::current()->databaseObserver()->reportOpenDatabaseResult(
    611             createDatabaseIdentifierFromSecurityOrigin(securityOrigin()),
    612             stringIdentifier(), isSyncDatabase(),
    613             errorSite, webSqlErrorCode, sqliteErrorCode);
    614     }
    615 }
    616 
    617 void DatabaseBackendBase::reportChangeVersionResult(int errorSite, int webSqlErrorCode, int sqliteErrorCode)
    618 {
    619     if (blink::Platform::current()->databaseObserver()) {
    620         blink::Platform::current()->databaseObserver()->reportChangeVersionResult(
    621             createDatabaseIdentifierFromSecurityOrigin(securityOrigin()),
    622             stringIdentifier(), isSyncDatabase(),
    623             errorSite, webSqlErrorCode, sqliteErrorCode);
    624     }
    625 }
    626 
    627 void DatabaseBackendBase::reportStartTransactionResult(int errorSite, int webSqlErrorCode, int sqliteErrorCode)
    628 {
    629     if (blink::Platform::current()->databaseObserver()) {
    630         blink::Platform::current()->databaseObserver()->reportStartTransactionResult(
    631             createDatabaseIdentifierFromSecurityOrigin(securityOrigin()),
    632             stringIdentifier(), isSyncDatabase(),
    633             errorSite, webSqlErrorCode, sqliteErrorCode);
    634     }
    635 }
    636 
    637 void DatabaseBackendBase::reportCommitTransactionResult(int errorSite, int webSqlErrorCode, int sqliteErrorCode)
    638 {
    639     if (blink::Platform::current()->databaseObserver()) {
    640         blink::Platform::current()->databaseObserver()->reportCommitTransactionResult(
    641             createDatabaseIdentifierFromSecurityOrigin(securityOrigin()),
    642             stringIdentifier(), isSyncDatabase(),
    643             errorSite, webSqlErrorCode, sqliteErrorCode);
    644     }
    645 }
    646 
    647 void DatabaseBackendBase::reportExecuteStatementResult(int errorSite, int webSqlErrorCode, int sqliteErrorCode)
    648 {
    649     if (blink::Platform::current()->databaseObserver()) {
    650         blink::Platform::current()->databaseObserver()->reportExecuteStatementResult(
    651             createDatabaseIdentifierFromSecurityOrigin(securityOrigin()),
    652             stringIdentifier(), isSyncDatabase(),
    653             errorSite, webSqlErrorCode, sqliteErrorCode);
    654     }
    655 }
    656 
    657 void DatabaseBackendBase::reportVacuumDatabaseResult(int sqliteErrorCode)
    658 {
    659     if (blink::Platform::current()->databaseObserver()) {
    660         blink::Platform::current()->databaseObserver()->reportVacuumDatabaseResult(
    661             createDatabaseIdentifierFromSecurityOrigin(securityOrigin()),
    662             stringIdentifier(), isSyncDatabase(), sqliteErrorCode);
    663     }
    664 }
    665 
    666 
    667 } // namespace WebCore
    668