icondatabase.cpp

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    return m_threadTerminationRequested || m_removeIconsRequested;
}

void* IconDatabase::iconDatabaseSyncThreadStart(void* vIconDatabase)
{    
    IconDatabase* iconDB = static_cast<IconDatabase*>(vIconDatabase);
    
    return iconDB->iconDatabaseSyncThread();
}

void* IconDatabase::iconDatabaseSyncThread()
{
    // The call to create this thread might not complete before the thread actually starts, so we might fail this ASSERT_ICON_SYNC_THREAD() because the pointer 
    // to our thread structure hasn't been filled in yet.
    // To fix this, the main thread acquires this lock before creating us, then releases the lock after creation is complete.  A quick lock/unlock cycle here will 
    // prevent us from running before that call completes
    m_syncLock.lock();
    m_syncLock.unlock();

    ASSERT_ICON_SYNC_THREAD();
    
    LOG(IconDatabase, "(THREAD) IconDatabase sync thread started");

#ifndef NDEBUG
    double startTime = currentTime();
#endif

    // Need to create the database path if it doesn't already exist
    makeAllDirectories(m_databaseDirectory);

    // Existence of a journal file is evidence of a previous crash/force quit and automatically qualifies
    // us to do an integrity check
    String journalFilename = m_completeDatabasePath + "-journal";
    if (!checkIntegrityOnOpen) {
        AutodrainedPool pool;
        checkIntegrityOnOpen = fileExists(journalFilename);
    }
    
    {
        MutexLocker locker(m_syncLock);
        if (!m_syncDB.open(m_completeDatabasePath)) {
            LOG_ERROR("Unable to open icon database at path %s - %s", m_completeDatabasePath.ascii().data(), m_syncDB.lastErrorMsg());
            return 0;
        }
    }
    
    if (shouldStopThreadActivity())
        return syncThreadMainLoop();
        
#ifndef NDEBUG
    double timeStamp = currentTime();
    LOG(IconDatabase, "(THREAD) Open took %.4f seconds", timeStamp - startTime);
#endif    

    performOpenInitialization();
    if (shouldStopThreadActivity())
        return syncThreadMainLoop();
        
#ifndef NDEBUG
    double newStamp = currentTime();
    LOG(IconDatabase, "(THREAD) performOpenInitialization() took %.4f seconds, now %.4f seconds from thread start", newStamp - timeStamp, newStamp - startTime);
    timeStamp = newStamp;
#endif 

    if (!imported()) {
        LOG(IconDatabase, "(THREAD) Performing Safari2 import procedure");
        SQLiteTransaction importTransaction(m_syncDB);
        importTransaction.begin();
        
        // Commit the transaction only if the import completes (the import should be atomic)
        if (m_client->performImport()) {
            setImported(true);
            importTransaction.commit();
        } else {
            LOG(IconDatabase, "(THREAD) Safari 2 import was cancelled");
            importTransaction.rollback();
        }
        
        if (shouldStopThreadActivity())
            return syncThreadMainLoop();
            
#ifndef NDEBUG
        newStamp = currentTime();
        LOG(IconDatabase, "(THREAD) performImport() took %.4f seconds, now %.4f seconds from thread start", newStamp - timeStamp, newStamp - startTime);
        timeStamp = newStamp;
#endif 
    }
        
    // Uncomment the following line to simulate a long lasting URL import (*HUGE* icon databases, or network home directories)
    // while (currentTime() - timeStamp < 10);

    // Read in URL mappings from the database          
    LOG(IconDatabase, "(THREAD) Starting iconURL import");
    performURLImport();
    
    if (shouldStopThreadActivity())
        return syncThreadMainLoop();

#ifndef NDEBUG
    newStamp = currentTime();
    LOG(IconDatabase, "(THREAD) performURLImport() took %.4f seconds.  Entering main loop %.4f seconds from thread start", newStamp - timeStamp, newStamp - startTime);
#endif 

    LOG(IconDatabase, "(THREAD) Beginning sync");
    return syncThreadMainLoop();
}

static int databaseVersionNumber(SQLiteDatabase& db)
{
    return SQLiteStatement(db, "SELECT value FROM IconDatabaseInfo WHERE key = 'Version';").getColumnInt(0);
}

static bool isValidDatabase(SQLiteDatabase& db)
{

    // These four tables should always exist in a valid db
    if (!db.tableExists("IconInfo") || !db.tableExists("IconData") || !db.tableExists("PageURL") || !db.tableExists("IconDatabaseInfo"))
        return false;
    
    if (databaseVersionNumber(db) < currentDatabaseVersion) {
        LOG(IconDatabase, "DB version is not found or below expected valid version");
        return false;
    }
    
    return true;
}

static void createDatabaseTables(SQLiteDatabase& db)
{
    if (!db.executeCommand("CREATE TABLE PageURL (url TEXT NOT NULL ON CONFLICT FAIL UNIQUE ON CONFLICT REPLACE,iconID INTEGER NOT NULL ON CONFLICT FAIL);")) {
        LOG_ERROR("Could not create PageURL table in database (%i) - %s", db.lastError(), db.lastErrorMsg());
        db.close();
        return;
    }
    if (!db.executeCommand("CREATE INDEX PageURLIndex ON PageURL (url);")) {
        LOG_ERROR("Could not create PageURL index in database (%i) - %s", db.lastError(), db.lastErrorMsg());
        db.close();
        return;
    }
    if (!db.executeCommand("CREATE TABLE IconInfo (iconID INTEGER PRIMARY KEY AUTOINCREMENT UNIQUE ON CONFLICT REPLACE, url TEXT NOT NULL ON CONFLICT FAIL UNIQUE ON CONFLICT FAIL, stamp INTEGER);")) {
        LOG_ERROR("Could not create IconInfo table in database (%i) - %s", db.lastError(), db.lastErrorMsg());
        db.close();
        return;
    }
    if (!db.executeCommand("CREATE INDEX IconInfoIndex ON IconInfo (url, iconID);")) {
        LOG_ERROR("Could not create PageURL index in database (%i) - %s", db.lastError(), db.lastErrorMsg());
        db.close();
        return;
    }
    if (!db.executeCommand("CREATE TABLE IconData (iconID INTEGER PRIMARY KEY AUTOINCREMENT UNIQUE ON CONFLICT REPLACE, data BLOB);")) {
        LOG_ERROR("Could not create IconData table in database (%i) - %s", db.lastError(), db.lastErrorMsg());
        db.close();
        return;
    }
    if (!db.executeCommand("CREATE INDEX IconDataIndex ON IconData (iconID);")) {
        LOG_ERROR("Could not create PageURL index in database (%i) - %s", db.lastError(), db.lastErrorMsg());
        db.close();
        return;
    }
    if (!db.executeCommand("CREATE TABLE IconDatabaseInfo (key TEXT NOT NULL ON CONFLICT FAIL UNIQUE ON CONFLICT REPLACE,value TEXT NOT NULL ON CONFLICT FAIL);")) {
        LOG_ERROR("Could not create IconDatabaseInfo table in database (%i) - %s", db.lastError(), db.lastErrorMsg());
        db.close();
        return;
    }
    if (!db.executeCommand(String("INSERT INTO IconDatabaseInfo VALUES ('Version', ") + String::number(currentDatabaseVersion) + ");")) {
        LOG_ERROR("Could not insert icon database version into IconDatabaseInfo table (%i) - %s", db.lastError(), db.lastErrorMsg());
        db.close();
        return;
    }
}    

void IconDatabase::performOpenInitialization()
{
    ASSERT_ICON_SYNC_THREAD();
    
    if (!isOpen())
        return;
    
    if (checkIntegrityOnOpen) {
        checkIntegrityOnOpen = false;
        if (!checkIntegrity()) {
            LOG(IconDatabase, "Integrity check was bad - dumping IconDatabase");

            m_syncDB.close();
            
            {
                MutexLocker locker(m_syncLock);
                // Should've been consumed by SQLite, delete just to make sure we don't see it again in the future;
                deleteFile(m_completeDatabasePath + "-journal");
                deleteFile(m_completeDatabasePath);
            }
            
            // Reopen the write database, creating it from scratch
            if (!m_syncDB.open(m_completeDatabasePath)) {
                LOG_ERROR("Unable to open icon database at path %s - %s", m_completeDatabasePath.ascii().data(), m_syncDB.lastErrorMsg());
                return;
            }          
        }
    }
    
    int version = databaseVersionNumber(m_syncDB);
    
    if (version > currentDatabaseVersion) {
        LOG(IconDatabase, "Database version number %i is greater than our current version number %i - closing the database to prevent overwriting newer versions", version, currentDatabaseVersion);
        m_syncDB.close();
        m_threadTerminationRequested = true;
        return;
    }
    
    if (!isValidDatabase(m_syncDB)) {
        LOG(IconDatabase, "%s is missing or in an invalid state - reconstructing", m_completeDatabasePath.ascii().data());
        m_syncDB.clearAllTables();
        createDatabaseTables(m_syncDB);
    }

    // Reduce sqlite RAM cache size from default 2000 pages (~1.5kB per page). 3MB of cache for icon database is overkill
    if (!SQLiteStatement(m_syncDB, "PRAGMA cache_size = 200;").executeCommand())         
        LOG_ERROR("SQLite database could not set cache_size");
}

bool IconDatabase::checkIntegrity()
{
    ASSERT_ICON_SYNC_THREAD();
    
    SQLiteStatement integrity(m_syncDB, "PRAGMA integrity_check;");
    if (integrity.prepare() != SQLResultOk) {
        LOG_ERROR("checkIntegrity failed to execute");
        return false;
    }
    
    int resultCode = integrity.step();
    if (resultCode == SQLResultOk)
        return true;
        
    if (resultCode != SQLResultRow)
        return false;

    int columns = integrity.columnCount();
    if (columns != 1) {
        LOG_ERROR("Received %i columns performing integrity check, should be 1", columns);
        return false;
    }
        
    String resultText = integrity.getColumnText(0);
        
    // A successful, no-error integrity check will be "ok" - all other strings imply failure
    if (resultText == "ok")
        return true;
    
    LOG_ERROR("Icon database integrity check failed - \n%s", resultText.ascii().data());
    return false;
}

void IconDatabase::performURLImport()
{
    ASSERT_ICON_SYNC_THREAD();

    SQLiteStatement query(m_syncDB, "SELECT PageURL.url, IconInfo.url, IconInfo.stamp FROM PageURL INNER JOIN IconInfo ON PageURL.iconID=IconInfo.iconID;");
    
    if (query.prepare() != SQLResultOk) {
        LOG_ERROR("Unable to prepare icon url import query");
        return;
    }
    
    // Informal testing shows that draining the autorelease pool every 25 iterations is about as low as we can go
    // before performance starts to drop off, but we don't want to increase this number because then accumulated memory usage will go up
    AutodrainedPool pool(25);
        
    int result = query.step();
    while (result == SQLResultRow) {
        String pageURL = query.getColumnText(0);
        String iconURL = query.getColumnText(1);

        {
            MutexLocker locker(m_urlAndIconLock);
            
            PageURLRecord* pageRecord = m_pageURLToRecordMap.get(pageURL);
            
            // If the pageRecord doesn't exist in this map, then no one has retained this pageURL
            // If the s_databaseCleanupCounter count is non-zero, then we're not supposed to be pruning the database in any manner,
            // so go ahead and actually create a pageURLRecord for this url even though it's not retained.
            // If database cleanup *is* allowed, we don't want to bother pulling in a page url from disk that noone is actually interested
            // in - we'll prune it later instead!
            if (!pageRecord && databaseCleanupCounter && !pageURL.isEmpty()) {
                pageRecord = new PageURLRecord(pageURL);
                m_pageURLToRecordMap.set(pageURL, pageRecord);
            }
            
            if (pageRecord) {
                IconRecord* currentIcon = pageRecord->iconRecord();

                if (!currentIcon || currentIcon->iconURL() != iconURL) {
                    pageRecord->setIconRecord(getOrCreateIconRecord(iconURL));
                    currentIcon = pageRecord->iconRecord();
                }
            
                // Regardless, the time stamp from disk still takes precedence.  Until we read this icon from disk, we didn't think we'd seen it before
                // so we marked the timestamp as "now", but it's really much older
                currentIcon->setTimestamp(query.getColumnInt(2));
            }            
        }
        
        // FIXME: Currently the WebKit API supports 1 type of notification that is sent whenever we get an Icon URL for a Page URL.  We might want to re-purpose it to work for 
        // getting the actually icon itself also (so each pageurl would get this notification twice) or we might want to add a second type of notification -
        // one for the URL and one for the Image itself
        // Note that WebIconDatabase is not neccessarily API so we might be able to make this change
        {
            MutexLocker locker(m_pendingReadingLock);
            if (m_pageURLsPendingImport.contains(pageURL)) {
                m_client->dispatchDidAddIconForPageURL(pageURL);
                m_pageURLsPendingImport.remove(pageURL);