Source/WebCore/Modules/webdatabase/DatabaseTask.cpp

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#include "config.h"
#include "DatabaseTask.h"

#include "Database.h"
#include "Logging.h"
#include "SQLTransaction.h"

namespace WebCore {

DatabaseTaskSynchronizer::DatabaseTaskSynchronizer()
{
}

void DatabaseTaskSynchronizer::waitForTaskCompletion()
{
    m_synchronousMutex.lock();
    while (!m_taskCompleted)
        m_synchronousCondition.wait(m_synchronousMutex);
    m_synchronousMutex.unlock();
}

void DatabaseTaskSynchronizer::taskCompleted()
{
    m_synchronousMutex.lock();
    m_taskCompleted = true;
    m_synchronousCondition.notifyOne();
    m_synchronousMutex.unlock();
}

DatabaseTask::DatabaseTask(Database& database, DatabaseTaskSynchronizer* synchronizer)
    : m_database(database)
    , m_synchronizer(synchronizer)
{
}

DatabaseTask::~DatabaseTask()
{
    ASSERT(m_complete || !m_synchronizer);
}

void DatabaseTask::performTask()
{
    // Database tasks are meant to be used only once, so make sure this one hasn't been performed before.
    ASSERT(!m_complete);

    LOG(StorageAPI, "Performing %s %p\n", debugTaskName(), this);

    m_database.resetAuthorizer();

    doPerformTask();

    if (m_synchronizer)
        m_synchronizer->taskCompleted();

#if ASSERT_ENABLED
    m_complete = true;
#endif
}

// *** DatabaseOpenTask ***
// Opens the database file and verifies the version matches the expected version.

DatabaseOpenTask::DatabaseOpenTask(Database& database, bool setVersionInNewDatabase, DatabaseTaskSynchronizer& synchronizer, ExceptionOr<void>& result)
    : DatabaseTask(database, &synchronizer)
    , m_setVersionInNewDatabase(setVersionInNewDatabase)
    , m_result(result)
{
}

void DatabaseOpenTask::doPerformTask()
{
    m_result = isolatedCopy(database().performOpenAndVerify(m_setVersionInNewDatabase));
}

#if !LOG_DISABLED

const char* DatabaseOpenTask::debugTaskName() const
{
    return "DatabaseOpenTask";
}

#endif

// *** DatabaseCloseTask ***
// Closes the database.

DatabaseCloseTask::DatabaseCloseTask(Database& database, DatabaseTaskSynchronizer& synchronizer)
    : DatabaseTask(database, &synchronizer)
{
}

void DatabaseCloseTask::doPerformTask()
{
    database().performClose();
}

#if !LOG_DISABLED

const char* DatabaseCloseTask::debugTaskName() const
{
    return "DatabaseCloseTask";
}

#endif

// *** DatabaseTransactionTask ***
// Starts a transaction that will report its results via a callback.

DatabaseTransactionTask::DatabaseTransactionTask(RefPtr<SQLTransaction>&& transaction)
    : DatabaseTask(transaction->database(), 0)
    , m_transaction(WTFMove(transaction))
    , m_didPerformTask(false)
{
}

DatabaseTransactionTask::~DatabaseTransactionTask()
{
    // If the task is being destructed without the transaction ever being run,
    // then we must either have an error or an interruption. Give the
    // transaction a chance to clean up since it may not have been able to
    // run to its clean up state.

    // Transaction phase 2 cleanup. See comment on "What happens if a
    // transaction is interrupted?" at the top of SQLTransactionBackend.cpp.

    if (!m_didPerformTask)
        m_transaction->notifyDatabaseThreadIsShuttingDown();
}

void DatabaseTransactionTask::doPerformTask()
{
    m_transaction->performNextStep();
    m_didPerformTask = true;
}

#if !LOG_DISABLED

const char* DatabaseTransactionTask::debugTaskName() const
{
    return "DatabaseTransactionTask";
}

#endif

// *** DatabaseTableNamesTask ***
// Retrieves a list of all tables in the database - for WebInspector support.

DatabaseTableNamesTask::DatabaseTableNamesTask(Database& database, DatabaseTaskSynchronizer& synchronizer, Vector<String>& result)
    : DatabaseTask(database, &synchronizer)
    , m_result(result)
{
}

void DatabaseTableNamesTask::doPerformTask()
{
    // FIXME: Why no need for an isolatedCopy here?
    m_result = database().performGetTableNames();
}

#if !LOG_DISABLED

const char* DatabaseTableNamesTask::debugTaskName() const
{
    return "DatabaseTableNamesTask";
}

#endif

} // namespace WebCore