RowSet.cpp

/*
 * MIT License
 *
 * Copyright (c) 2026 F.D.Castel
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
 
#include "RowSet.h"
#include "Attachment.h"
#include "Client.h"
#include "Statement.h"
#include <algorithm>
 
using namespace fbcpp;
using namespace fbcpp::impl;
 
 
RowSet::RowSet(Statement& statement, unsigned maxRows)
    : client{&statement.getAttachment().getClient()},
      statusWrapper{statement.getAttachment().getClient()},
      numericConverter{statement.getAttachment().getClient()},
      calendarConverter{statement.getAttachment().getClient()}
{
    assert(statement.isValid());
    assert(statement.hasCurrentRow() || statement.getResultSetHandle());
 
    descriptors = statement.getOutputDescriptors();
 
    auto outMetadata = statement.getOutputMetadata();
    messageLength = outMetadata->getMessageLength(&statusWrapper);
 
    buffer.resize(static_cast<std::size_t>(maxRows) * messageLength);
 
    auto resultSet = statement.getResultSetHandle();
    auto* dest = buffer.data();
 
    if (statement.hasCurrentRow() && maxRows > 0u)
    {
        auto& currentRow = statement.getOutputMessage();
        assert(currentRow.size() == messageLength);
        std::copy(currentRow.begin(), currentRow.end(), dest);
        dest += messageLength;
        ++count;
        statement.clearCurrentRow();
    }
 
    if (!resultSet)
    {
        buffer.resize(static_cast<std::size_t>(dest - buffer.data()));
        return;
    }
 
    for (unsigned i = count; i < maxRows; ++i)
    {
        if (resultSet->fetchNext(&statusWrapper, dest) != fb::IStatus::RESULT_OK)
            break;
 
        dest += messageLength;
        ++count;
    }
 
    buffer.resize(static_cast<std::size_t>(dest - buffer.data()));
}