vmime/src/utility/seekableInputStreamRegionAdapter.cpp

107 lines
2.5 KiB
C++

//
// VMime library (http://www.vmime.org)
// Copyright (C) 2002-2013 Vincent Richard <vincent@vmime.org>
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 3 of
// the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
//
// Linking this library statically or dynamically with other modules is making
// a combined work based on this library. Thus, the terms and conditions of
// the GNU General Public License cover the whole combination.
//
#include "vmime/utility/seekableInputStreamRegionAdapter.hpp"
namespace vmime {
namespace utility {
seekableInputStreamRegionAdapter::seekableInputStreamRegionAdapter
(ref <seekableInputStream> stream, const size_type begin, const size_type length)
: m_stream(stream), m_begin(begin), m_length(length), m_position(0)
{
}
bool seekableInputStreamRegionAdapter::eof() const
{
return m_position >= m_length;
}
void seekableInputStreamRegionAdapter::reset()
{
m_position = 0;
}
stream::size_type seekableInputStreamRegionAdapter::read
(value_type* const data, const size_type count)
{
m_stream->seek(m_begin + m_position);
size_type readBytes = 0;
if (m_position + count >= m_length)
{
const size_type remaining = m_length - m_position;
readBytes = m_stream->read(data, remaining);
}
else
{
readBytes = m_stream->read(data, count);
}
m_position += readBytes;
return readBytes;
}
stream::size_type seekableInputStreamRegionAdapter::skip(const size_type count)
{
if (m_position + count >= m_length)
{
const size_type remaining = m_length - m_position;
m_position += remaining;
return remaining;
}
else
{
m_position += count;
return count;
}
}
stream::size_type seekableInputStreamRegionAdapter::getPosition() const
{
return m_position;
}
void seekableInputStreamRegionAdapter::seek(const size_type pos)
{
if (pos > m_length)
m_position = m_length;
else
m_position = pos;
}
} // utility
} // vmime