Redesign RSS subsystem

src/base/asyncfilestorage.cpp

@@ -0,0 +1,88 @@
+/*
+ * Bittorrent Client using Qt and libtorrent.
+ * Copyright (C) 2017  Vladimir Golovnev <glassez@yandex.ru>
+ *
+ * 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, Boston, MA  02110-1301, USA.
+ *
+ * In addition, as a special exception, the copyright holders give permission to
+ * link this program with the OpenSSL project's "OpenSSL" library (or with
+ * modified versions of it that use the same license as the "OpenSSL" library),
+ * and distribute the linked executables. You must obey the GNU General Public
+ * License in all respects for all of the code used other than "OpenSSL".  If you
+ * modify file(s), you may extend this exception to your version of the file(s),
+ * but you are not obligated to do so. If you do not wish to do so, delete this
+ * exception statement from your version.
+ */
+
+#include "asyncfilestorage.h"
+
+#include <QDebug>
+#include <QMetaObject>
+#include <QSaveFile>
+
+AsyncFileStorage::AsyncFileStorage(const QString &storageFolderPath, QObject *parent)
+    : QObject(parent)
+    , m_storageDir(storageFolderPath)
+    , m_lockFile(m_storageDir.absoluteFilePath(QStringLiteral("storage.lock")))
+{
+    if (!m_storageDir.mkpath(m_storageDir.absolutePath()))
+        throw AsyncFileStorageError(
+                QString("Could not create directory '%1'.").arg(m_storageDir.absolutePath()));
+
+    // TODO: This folder locking approach does not work for UNIX systems. Implement it.
+    if (!m_lockFile.open(QFile::WriteOnly))
+        throw AsyncFileStorageError(m_lockFile.errorString());
+}
+
+AsyncFileStorage::~AsyncFileStorage()
+{
+    m_lockFile.close();
+    m_lockFile.remove();
+}
+
+void AsyncFileStorage::store(const QString &fileName, const QByteArray &data)
+{
+    QMetaObject::invokeMethod(this, "store_impl", Qt::QueuedConnection
+                              , Q_ARG(QString, fileName), Q_ARG(QByteArray, data));
+}
+
+QDir AsyncFileStorage::storageDir() const
+{
+    return m_storageDir;
+}
+
+void AsyncFileStorage::store_impl(const QString &fileName, const QByteArray &data)
+{
+    const QString filePath = m_storageDir.absoluteFilePath(fileName);
+    QSaveFile file(filePath);
+    qDebug() << "AsyncFileStorage: Saving data to" << filePath;
+    if (file.open(QIODevice::WriteOnly)) {
+        file.write(data);
+        if (!file.commit()) {
+            qDebug() << "AsyncFileStorage: Failed to save data";
+            emit failed(filePath, file.errorString());
+        }
+    }
+}
+
+AsyncFileStorageError::AsyncFileStorageError(const QString &message)
+    : std::runtime_error(message.toUtf8().data())
+{
+}
+
+QString AsyncFileStorageError::message() const
+{
+    return what();
+}