Function copyDataImpl

src/DataStreams/copyData.cpp:21–50

template <typename TCancelCallback, typename TProgressCallback>
void copyDataImpl(IBlockInputStream & from, IBlockOutputStream & to, TCancelCallback && is_cancelled, TProgressCallback && progress)
{
    from.readPrefix();
    to.writePrefix();

    while (Block block = from.read())
    {
        if (is_cancelled())
            break;

        to.write(block);
        progress(block);
    }

    if (is_cancelled())
        return;

    /// For outputting additional information in some formats.
    if (from.getProfileInfo().hasAppliedLimit())
        to.setRowsBeforeLimit(from.getProfileInfo().getRowsBeforeLimit());

    to.setTotals(from.getTotals());
    to.setExtremes(from.getExtremes());

    if (is_cancelled())
        return;

    from.readSuffix();
    to.writeSuffix();
}

void copyData(IBlockInputStream & from, IBlockOutputStream & to, const std::function<void(const Block & block)> & progress,
              std::atomic<bool> * is_cancelled)