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/****************************************************************************
**
** Copyright (C) 2016 Jochen Becher
** Contact: https://www.qt.io/licensing/
**
** This file is part of Qt Creator.
**
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3 as published by the Free Software
** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-3.0.html.
**
****************************************************************************/
#include "qcompressedfile.h"
#include "qmt/infrastructure/qmtassert.h"
// TODO create real compressed files that can be read by some archiver (gzip)
namespace qmt {
QCompressedDevice::QCompressedDevice(QObject *parent)
: QIODevice(parent)
{
}
QCompressedDevice::QCompressedDevice(QIODevice *targetDevice, QObject *parent)
: QIODevice(parent),
m_targetDevice(targetDevice)
{
}
QCompressedDevice::~QCompressedDevice()
{
flush();
}
void QCompressedDevice::setTargetDevice(QIODevice *targetDevice)
{
m_targetDevice = targetDevice;
}
void QCompressedDevice::close()
{
flush();
QIODevice::close();
}
qint64 QCompressedDevice::readData(char *data, qint64 maxlen)
{
QMT_ASSERT(m_targetDevice, return 0);
QMT_ASSERT(m_targetDevice->isOpen(), return 0);
QMT_ASSERT(m_targetDevice->openMode() == QIODevice::ReadOnly, return 0);
if (m_bytesInBuffer == 0) {
QByteArray compressedBuffer;
int compressedLen = 0;
if (m_targetDevice->read(reinterpret_cast<char *>(&compressedLen), sizeof(int)) != sizeof(int))
return -1;
compressedBuffer.resize(compressedLen);
qint64 compressedBytes = m_targetDevice->read(compressedBuffer.data(), compressedLen);
m_buffer = qUncompress((const uchar *) compressedBuffer.data(), compressedBytes);
m_bytesInBuffer = m_buffer.size();
if (m_bytesInBuffer == 0)
return 0;
m_indexInBuffer = 0;
}
qint64 n = std::min(maxlen, m_bytesInBuffer);
memcpy(data, m_buffer.data() + m_indexInBuffer, n);
m_bytesInBuffer -= n;
m_indexInBuffer += n;
return n;
}
qint64 QCompressedDevice::writeData(const char *data, qint64 len)
{
QMT_ASSERT(m_targetDevice, return 0);
QMT_ASSERT(m_targetDevice->isOpen(), return 0);
QMT_ASSERT(m_targetDevice->openMode() == QIODevice::WriteOnly, return 0);
m_buffer.append(data, len);
if (m_buffer.size() > 1024*1024) {
QByteArray compressedBuffer = qCompress(m_buffer);
int compressedLen = static_cast<int>(compressedBuffer.size());
if (m_targetDevice->write(reinterpret_cast<const char *>(&compressedLen), sizeof(int)) != sizeof(int))
return -1;
if (m_targetDevice->write(compressedBuffer.data(), compressedLen) != compressedBuffer.size())
return -1;
m_buffer.clear();
}
return len;
}
qint64 QCompressedDevice::flush()
{
if (openMode() == QIODevice::WriteOnly && m_buffer.size() > 0) {
QMT_ASSERT(m_targetDevice->isOpen(), return 0);
QMT_ASSERT(m_targetDevice->openMode() == QIODevice::WriteOnly, return 0);
QByteArray compressedBuffer = qCompress(m_buffer);
int compressedLen = static_cast<int>(compressedBuffer.size());
if (m_targetDevice->write(reinterpret_cast<const char *>(&compressedLen), sizeof(int)) != sizeof(int))
return -1;
return m_targetDevice->write(compressedBuffer.data(), compressedLen);
}
return 0;
}
} // namespace qmt
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