kde-extraapps/gwenview/lib/thumbnailprovider/thumbnailwriter.cpp
2015-02-27 11:02:43 +00:00

104 lines
2.5 KiB
C++

// vim: set tabstop=4 shiftwidth=4 expandtab:
/*
Gwenview: an image viewer
Copyright 2012 Aurélien Gâteau <agateau@kde.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 2
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, Cambridge, MA 02110-1301, USA.
*/
// Self
#include "moc_thumbnailwriter.cpp"
// Local
// KDE
#include <KDebug>
#include <KTemporaryFile>
#include <kde_file.h>
// Qt
#include <QImage>
namespace Gwenview
{
#undef ENABLE_LOG
#undef LOG
//#define ENABLE_LOG
#ifdef ENABLE_LOG
#define LOG(x) kDebug() << x
#else
#define LOG(x) ;
#endif
static void storeThumbnailToDiskCache(const QString& path, const QImage& image)
{
LOG(path);
KTemporaryFile tmp;
tmp.setPrefix(path + ".gwenview.tmp");
tmp.setSuffix(".png");
if (!tmp.open()) {
kWarning() << "Could not create a temporary file.";
return;
}
if (!image.save(tmp.fileName(), "png")) {
kWarning() << "Could not save thumbnail";
return;
}
KDE_rename(QFile::encodeName(tmp.fileName()), QFile::encodeName(path));
}
void ThumbnailWriter::queueThumbnail(const QString& path, const QImage& image)
{
LOG(path);
QMutexLocker locker(&mMutex);
mCache.insert(path, image);
start();
}
void ThumbnailWriter::run()
{
QMutexLocker locker(&mMutex);
while (!mCache.isEmpty()) {
Cache::ConstIterator it = mCache.constBegin();
const QString path = it.key();
const QImage image = it.value();
// This part of the thread is the most time consuming but it does not
// depend on mCache so we can unlock here. This way other thumbnails
// can be added or queried
locker.unlock();
storeThumbnailToDiskCache(path, image);
locker.relock();
mCache.remove(path);
}
}
QImage ThumbnailWriter::value(const QString& path) const
{
QMutexLocker locker(&mMutex);
return mCache.value(path);
}
bool ThumbnailWriter::isEmpty() const
{
QMutexLocker locker(&mMutex);
return mCache.isEmpty();
}
} // namespace