applicationcachestorage.cpp

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    ASSERT(group->storageID() == 0);

    SQLiteStatement statement(m_database, "INSERT INTO CacheGroups (manifestHostHash, manifestURL) VALUES (?, ?)");
    if (statement.prepare() != SQLResultOk)
        return false;

    statement.bindInt64(1, urlHostHash(group->manifestURL()));
    statement.bindText(2, group->manifestURL());

    if (!executeStatement(statement))
        return false;

    group->setStorageID(static_cast<unsigned>(m_database.lastInsertRowID()));
    return true;
}    

bool ApplicationCacheStorage::store(ApplicationCache* cache)
{
    ASSERT(cache->storageID() == 0);
    ASSERT(cache->group()->storageID() != 0);
    
    SQLiteStatement statement(m_database, "INSERT INTO Caches (cacheGroup) VALUES (?)");
    if (statement.prepare() != SQLResultOk)
        return false;

    statement.bindInt64(1, cache->group()->storageID());

    if (!executeStatement(statement))
        return false;
    
    unsigned cacheStorageID = static_cast<unsigned>(m_database.lastInsertRowID());

    // Store all resources
    {
        ApplicationCache::ResourceMap::const_iterator end = cache->end();
        for (ApplicationCache::ResourceMap::const_iterator it = cache->begin(); it != end; ++it) {
            if (!store(it->second.get(), cacheStorageID))
                return false;
        }
    }
    
    // Store the online whitelist
    const Vector<KURL>& onlineWhitelist = cache->onlineWhitelist();
    {
        size_t whitelistSize = onlineWhitelist.size();
        for (size_t i = 0; i < whitelistSize; ++i) {
            SQLiteStatement statement(m_database, "INSERT INTO CacheWhitelistURLs (url, cache) VALUES (?, ?)");
            statement.prepare();

            statement.bindText(1, onlineWhitelist[i]);
            statement.bindInt64(2, cacheStorageID);

            if (!executeStatement(statement))
                return false;
        }
    }
    
    // Store fallback URLs.
    const FallbackURLVector& fallbackURLs = cache->fallbackURLs();
    {
        size_t fallbackCount = fallbackURLs.size();
        for (size_t i = 0; i < fallbackCount; ++i) {
            SQLiteStatement statement(m_database, "INSERT INTO FallbackURLs (namespace, fallbackURL, cache) VALUES (?, ?, ?)");
            statement.prepare();

            statement.bindText(1, fallbackURLs[i].first);
            statement.bindText(2, fallbackURLs[i].second);
            statement.bindInt64(3, cacheStorageID);

            if (!executeStatement(statement))
                return false;
        }
    }

    cache->setStorageID(cacheStorageID);
    return true;
}

bool ApplicationCacheStorage::store(ApplicationCacheResource* resource, unsigned cacheStorageID)
{
    ASSERT(cacheStorageID);
    ASSERT(!resource->storageID());
    
    openDatabase(true);
    
    // First, insert the data
    SQLiteStatement dataStatement(m_database, "INSERT INTO CacheResourceData (data) VALUES (?)");
    if (dataStatement.prepare() != SQLResultOk)
        return false;
    
    if (resource->data()->size())
        dataStatement.bindBlob(1, resource->data()->data(), resource->data()->size());
    
    if (!dataStatement.executeCommand())
        return false;

    unsigned dataId = static_cast<unsigned>(m_database.lastInsertRowID());

    // Then, insert the resource
    
    // Serialize the headers
    Vector<UChar> stringBuilder;
    
    HTTPHeaderMap::const_iterator end = resource->response().httpHeaderFields().end();
    for (HTTPHeaderMap::const_iterator it = resource->response().httpHeaderFields().begin(); it!= end; ++it) {
        stringBuilder.append(it->first.characters(), it->first.length());
        stringBuilder.append((UChar)':');
        stringBuilder.append(it->second.characters(), it->second.length());
        stringBuilder.append((UChar)'\n');
    }
    
    String headers = String::adopt(stringBuilder);
    
    SQLiteStatement resourceStatement(m_database, "INSERT INTO CacheResources (url, statusCode, responseURL, headers, data, mimeType, textEncodingName) VALUES (?, ?, ?, ?, ?, ?, ?)");
    if (resourceStatement.prepare() != SQLResultOk)
        return false;
    
    resourceStatement.bindText(1, resource->url());
    resourceStatement.bindInt64(2, resource->response().httpStatusCode());
    resourceStatement.bindText(3, resource->response().url());
    resourceStatement.bindText(4, headers);
    resourceStatement.bindInt64(5, dataId);
    resourceStatement.bindText(6, resource->response().mimeType());
    resourceStatement.bindText(7, resource->response().textEncodingName());

    if (!executeStatement(resourceStatement))
        return false;

    unsigned resourceId = static_cast<unsigned>(m_database.lastInsertRowID());
    
    // Finally, insert the cache entry
    SQLiteStatement entryStatement(m_database, "INSERT INTO CacheEntries (cache, type, resource) VALUES (?, ?, ?)");
    if (entryStatement.prepare() != SQLResultOk)
        return false;
    
    entryStatement.bindInt64(1, cacheStorageID);
    entryStatement.bindInt64(2, resource->type());
    entryStatement.bindInt64(3, resourceId);
    
    if (!executeStatement(entryStatement))
        return false;
    
    resource->setStorageID(resourceId);
    return true;
}

bool ApplicationCacheStorage::storeUpdatedType(ApplicationCacheResource* resource, ApplicationCache* cache)
{
    ASSERT_UNUSED(cache, cache->storageID());
    ASSERT(resource->storageID());

    // FIXME: If the resource gained a Dynamic bit, it should be re-inserted at the end for correct order.
    ASSERT(!(resource->type() & ApplicationCacheResource::Dynamic));
    
    // First, insert the data
    SQLiteStatement entryStatement(m_database, "UPDATE CacheEntries SET type=? WHERE resource=?");
    if (entryStatement.prepare() != SQLResultOk)
        return false;

    entryStatement.bindInt64(1, resource->type());
    entryStatement.bindInt64(2, resource->storageID());

    return executeStatement(entryStatement);
}

void ApplicationCacheStorage::store(ApplicationCacheResource* resource, ApplicationCache* cache)
{
    ASSERT(cache->storageID());
    
    openDatabase(true);
 
    SQLiteTransaction storeResourceTransaction(m_database);
    storeResourceTransaction.begin();
    
    if (!store(resource, cache->storageID()))
        return;
    
    storeResourceTransaction.commit();
}

bool ApplicationCacheStorage::storeNewestCache(ApplicationCacheGroup* group)
{
    openDatabase(true);
    
    SQLiteTransaction storeCacheTransaction(m_database);
    
    storeCacheTransaction.begin();
    
    if (!group->storageID()) {
        // Store the group
        if (!store(group))
            return false;
    }
    
    ASSERT(group->newestCache());
    ASSERT(!group->isObsolete());
    ASSERT(!group->newestCache()->storageID());
    
    // Store the newest cache
    if (!store(group->newestCache()))
        return false;
    
    // Update the newest cache in the group.
    
    SQLiteStatement statement(m_database, "UPDATE CacheGroups SET newestCache=? WHERE id=?");
    if (statement.prepare() != SQLResultOk)
        return false;
    
    statement.bindInt64(1, group->newestCache()->storageID());
    statement.bindInt64(2, group->storageID());
    
    if (!executeStatement(statement))
        return false;
    
    storeCacheTransaction.commit();
    return true;
}

static inline void parseHeader(const UChar* header, size_t headerLength, ResourceResponse& response)
{
    int pos = find(header, headerLength, ':');
    ASSERT(pos != -1);
    
    AtomicString headerName = AtomicString(header, pos);
    String headerValue = String(header + pos + 1, headerLength - pos - 1);
    
    response.setHTTPHeaderField(headerName, headerValue);
}

static inline void parseHeaders(const String& headers, ResourceResponse& response)
{
    int startPos = 0;
    int endPos;
    while ((endPos = headers.find('\n', startPos)) != -1) {
        ASSERT(startPos != endPos);

        parseHeader(headers.characters() + startPos, endPos - startPos, response);
        
        startPos = endPos + 1;
    }
    
    if (startPos != static_cast<int>(headers.length()))
        parseHeader(headers.characters(), headers.length(), response);
}
    
PassRefPtr<ApplicationCache> ApplicationCacheStorage::loadCache(unsigned storageID)
{
    SQLiteStatement cacheStatement(m_database, 
                                   "SELECT url, type, mimeType, textEncodingName, headers, CacheResourceData.data FROM CacheEntries INNER JOIN CacheResources ON CacheEntries.resource=CacheResources.id "
                                   "INNER JOIN CacheResourceData ON CacheResourceData.id=CacheResources.data WHERE CacheEntries.cache=?");
    if (cacheStatement.prepare() != SQLResultOk) {
        LOG_ERROR("Could not prepare cache statement, error \"%s\"", m_database.lastErrorMsg());
        return 0;
    }
    
    cacheStatement.bindInt64(1, storageID);

    RefPtr<ApplicationCache> cache = ApplicationCache::create();
    
    int result;
    while ((result = cacheStatement.step()) == SQLResultRow) {
        KURL url(cacheStatement.getColumnText(0));
        
        unsigned type = static_cast<unsigned>(cacheStatement.getColumnInt64(1));

        Vector<char> blob;
        cacheStatement.getColumnBlobAsVector(5, blob);
        
        RefPtr<SharedBuffer> data = SharedBuffer::adoptVector(blob);
        
        String mimeType = cacheStatement.getColumnText(2);
        String textEncodingName = cacheStatement.getColumnText(3);
        
        ResourceResponse response(url, mimeType, data->size(), textEncodingName, "");

        String headers = cacheStatement.getColumnText(4);
        parseHeaders(headers, response);
        
        RefPtr<ApplicationCacheResource> resource = ApplicationCacheResource::create(url, response, type, data.release());

        if (type & ApplicationCacheResource::Manifest)
            cache->setManifestResource(resource.release());
        else
            cache->addResource(resource.release());
    }

    if (result != SQLResultDone)
        LOG_ERROR("Could not load cache resources, error \"%s\"", m_database.lastErrorMsg());
    
    // Load the online whitelist
    SQLiteStatement whitelistStatement(m_database, "SELECT url FROM CacheWhitelistURLs WHERE cache=?");
    if (whitelistStatement.prepare() != SQLResultOk)
        return 0;
    whitelistStatement.bindInt64(1, storageID);
    
    Vector<KURL> whitelist;
    while ((result = whitelistStatement.step()) == SQLResultRow) 
        whitelist.append(whitelistStatement.getColumnText(0));

    if (result != SQLResultDone)
        LOG_ERROR("Could not load cache online whitelist, error \"%s\"", m_database.lastErrorMsg());

    cache->setOnlineWhitelist(whitelist);

    // Load fallback URLs.
    SQLiteStatement fallbackStatement(m_database, "SELECT namespace, fallbackURL FROM FallbackURLs WHERE cache=?");
    if (fallbackStatement.prepare() != SQLResultOk)
        return 0;
    fallbackStatement.bindInt64(1, storageID);
    
    FallbackURLVector fallbackURLs;
    while ((result = fallbackStatement.step()) == SQLResultRow) 
        fallbackURLs.append(make_pair(fallbackStatement.getColumnText(0), fallbackStatement.getColumnText(1)));

    if (result != SQLResultDone)
        LOG_ERROR("Could not load fallback URLs, error \"%s\"", m_database.lastErrorMsg());

    cache->setFallbackURLs(fallbackURLs);
    
    cache->setStorageID(storageID);

    return cache.release();
}    
    
void ApplicationCacheStorage::remove(ApplicationCache* cache)
{
    if (!cache->storageID())
        return;
    
    openDatabase(false);
    if (!m_database.isOpen())
        return;

    ASSERT(cache->group());
    ASSERT(cache->group()->storageID());

    // All associated data will be deleted by database triggers.
    SQLiteStatement statement(m_database, "DELETE FROM Caches WHERE id=?");
    if (statement.prepare() != SQLResultOk)
        return;
    
    statement.bindInt64(1, cache->storageID());
    executeStatement(statement);

    cache->clearStorageID();

    if (cache->group()->newestCache() == cache) {
        // Currently, there are no triggers on the cache group, which is why the cache had to be removed separately above.
        SQLiteStatement groupStatement(m_database, "DELETE FROM CacheGroups WHERE id=?");
        if (groupStatement.prepare() != SQLResultOk)
            return;
        
        groupStatement.bindInt64(1, cache->group()->storageID());
        executeStatement(groupStatement);

        cache->group()->clearStorageID();
    }
}    

void ApplicationCacheStorage::empty()
{
    openDatabase(false);
    
    if (!m_database.isOpen())
        return;
    
    // Clear cache groups, caches and cache resources.
    executeSQLCommand("DELETE FROM CacheGroups");
    executeSQLCommand("DELETE FROM Caches");
    
    // Clear the storage IDs for the caches in memory.
    // The caches will still work, but cached resources will not be saved to disk 
    // until a cache update process has been initiated.
    CacheGroupMap::const_iterator end = m_cachesInMemory.end();
    for (CacheGroupMap::const_iterator it = m_cachesInMemory.begin(); it != end; ++it)
        it->second->clearStorageID();
}    

bool ApplicationCacheStorage::storeCopyOfCache(const String& cacheDirectory, ApplicationCache* cache)
{
    // Create a new cache.
    RefPtr<ApplicationCache> cacheCopy = ApplicationCache::create();

    cacheCopy->setOnlineWhitelist(cache->onlineWhitelist());
    cacheCopy->setFallbackURLs(cache->fallbackURLs());

    // Traverse the cache and add copies of all resources.
    ApplicationCache::ResourceMap::const_iterator end = cache->end();
    for (ApplicationCache::ResourceMap::const_iterator it = cache->begin(); it != end; ++it) {
        ApplicationCacheResource* resource = it->second.get();
        
        RefPtr<ApplicationCacheResource> resourceCopy = ApplicationCacheResource::create(resource->url(), resource->response(), resource->type(), resource->data());
        
        cacheCopy->addResource(resourceCopy.release());
    }
    
    // Now create a new cache group.
    OwnPtr<ApplicationCacheGroup> groupCopy(new ApplicationCacheGroup(cache->group()->manifestURL(), true));
    
    groupCopy->setNewestCache(cacheCopy);
    
    ApplicationCacheStorage copyStorage;
    copyStorage.setCacheDirectory(cacheDirectory);
    
    // Empty the cache in case something was there before.
    copyStorage.empty();
    
    return copyStorage.storeNewestCache(groupCopy.get());
}
    
ApplicationCacheStorage& cacheStorage()
{
    DEFINE_STATIC_LOCAL(ApplicationCacheStorage, storage, ());
    
    return storage;
}

} // namespace WebCore

#endif // ENABLE(OFFLINE_WEB_APPLICATIONS)