Improve interaction with backend

src/base/CMakeLists.txt

@@ -36,6 +36,7 @@ add_library(qbt_base STATIC
     bittorrent/speedmonitor.h
     bittorrent/sslparameters.h
     bittorrent/torrent.h
+    bittorrent/torrentbackend.h
     bittorrent/torrentcontenthandler.h
     bittorrent/torrentcontentlayout.h
     bittorrent/torrentcontentremoveoption.h
@@ -146,6 +147,7 @@ add_library(qbt_base STATIC
     bittorrent/speedmonitor.cpp
     bittorrent/sslparameters.cpp
     bittorrent/torrent.cpp
+    bittorrent/torrentbackend.cpp
     bittorrent/torrentcontenthandler.cpp
     bittorrent/torrentcontentremover.cpp
     bittorrent/torrentcreationmanager.cpp

src/base/bittorrent/sessionimpl.cpp

@@ -101,6 +101,7 @@
 #include "nativesessionextension.h"
 #include "portforwarderimpl.h"
 #include "resumedatastorage.h"
+#include "torrentbackend.h"
 #include "torrentcontentremover.h"
 #include "torrentdescriptor.h"
 #include "torrentimpl.h"
@@ -530,6 +531,7 @@ SessionImpl::SessionImpl(QObject *parent)
     , m_startPaused {BITTORRENT_SESSION_KEY(u"StartPaused"_s)}
     , m_seedingLimitTimer {new QTimer(this)}
     , m_resumeDataTimer {new QTimer(this)}
+    , m_backendThread {new QThread}
     , m_ioThread {new QThread}
     , m_asyncWorker {new QThreadPool(this)}
     , m_recentErroredTorrentsTimer {new QTimer(this)}
@@ -590,6 +592,8 @@ SessionImpl::SessionImpl(QObject *parent)
         , &Net::ProxyConfigurationManager::proxyConfigurationChanged
         , this, &SessionImpl::configureDeferred);
 
+    m_backendThread->start();
+
     m_fileSearcher = new FileSearcher;
     m_fileSearcher->moveToThread(m_ioThread.get());
     connect(m_ioThread.get(), &QThread::finished, m_fileSearcher, &QObject::deleteLater);
@@ -5698,7 +5702,13 @@ void SessionImpl::dispatchTorrentAlert(const lt::torrent_alert *alert)
 
 TorrentImpl *SessionImpl::createTorrent(const lt::torrent_handle &nativeHandle, const LoadTorrentParams &params)
 {
-    auto *const torrent = new TorrentImpl(this, m_nativeSession, nativeHandle, params);
+    auto *const torrentBackend = new TorrentBackend(m_nativeSession, nativeHandle);
+    torrentBackend->moveToThread(m_backendThread.get());
+    connect(m_backendThread.get(), &QThread::finished, torrentBackend, &QObject::deleteLater);
+
+    auto *const torrent = new TorrentImpl(this, torrentBackend, m_nativeSession, nativeHandle, params);
+    connect(torrent, &QObject::destroyed, torrentBackend, &QObject::deleteLater);
+
     m_torrents.insert(torrent->id(), torrent);
     if (const InfoHash infoHash = torrent->infoHash(); infoHash.isHybrid())
         m_hybridTorrentsByAltID.insert(TorrentID::fromSHA1Hash(infoHash.v1()), torrent);

src/base/bittorrent/sessionimpl.h

@@ -772,6 +772,7 @@ namespace BitTorrent
         // Tracker
         QPointer<Tracker> m_tracker;
 
+        Utils::Thread::UniquePtr m_backendThread;
         Utils::Thread::UniquePtr m_ioThread;
         QThreadPool *m_asyncWorker = nullptr;
         ResumeDataStorage *m_resumeDataStorage = nullptr;

src/base/bittorrent/torrentbackend.cpp

@@ -0,0 +1,86 @@
+/*
+ * Bittorrent Client using Qt and libtorrent.
+ * Copyright (C) 2024  Vladimir Golovnev <[email protected]>
+ *
+ * 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 "torrentbackend.h"
+
+#include <libtorrent/announce_entry.hpp>
+#include <libtorrent/session.hpp>
+
+namespace
+{
+    lt::announce_entry makeLTAnnounceEntry(const QString &url, const int tier)
+    {
+        lt::announce_entry entry {url.toStdString()};
+        entry.tier = tier;
+        return entry;
+    }
+}
+
+BitTorrent::TorrentBackend::TorrentBackend(lt::session *ltSession, lt::torrent_handle ltTorrentHandle, QObject *parent)
+    : QObject(parent)
+    , m_ltSession {ltSession}
+    , m_ltTorrentHandle {std::move(ltTorrentHandle)}
+{
+}
+
+void BitTorrent::TorrentBackend::addTrackers(const QList<TrackerEntry> &trackers)
+{
+    for (const TrackerEntry &tracker : trackers)
+        m_ltTorrentHandle.add_tracker(makeLTAnnounceEntry(tracker.url, tracker.tier));
+}
+
+void BitTorrent::TorrentBackend::replaceTrackers(const QList<TrackerEntry> &trackers)
+{
+    std::vector<lt::announce_entry> ltAnnounceEntries;
+    ltAnnounceEntries.reserve(trackers.size());
+    for (const TrackerEntry &tracker : trackers)
+        ltAnnounceEntries.emplace_back(makeLTAnnounceEntry(tracker.url, tracker.tier));
+    m_ltTorrentHandle.replace_trackers(ltAnnounceEntries);
+}
+
+void BitTorrent::TorrentBackend::addUrlSeeds(const QList<QUrl> &urlSeeds)
+{
+    for (const QUrl &url : urlSeeds)
+        m_ltTorrentHandle.add_url_seed(url.toString().toStdString());
+}
+
+void BitTorrent::TorrentBackend::removeUrlSeeds(const QList<QUrl> &urlSeeds)
+{
+    for (const QUrl &url : urlSeeds)
+        m_ltTorrentHandle.remove_url_seed(url.toString().toStdString());
+}
+
+void BitTorrent::TorrentBackend::clearPeers()
+{
+    m_ltTorrentHandle.clear_peers();
+}
+
+void BitTorrent::TorrentBackend::requestResumeData(const lt::resume_data_flags_t flags)
+{
+    m_ltTorrentHandle.save_resume_data(flags);
+}

src/base/bittorrent/torrentbackend.h

@@ -0,0 +1,61 @@
+/*
+ * Bittorrent Client using Qt and libtorrent.
+ * Copyright (C) 2024  Vladimir Golovnev <[email protected]>
+ *
+ * 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.
+ */
+
+#pragma once
+
+#include <libtorrent/fwd.hpp>
+#include <libtorrent/torrent_handle.hpp>
+
+#include <QList>
+#include <QObject>
+#include <QUrl>
+
+#include "trackerentry.h"
+
+namespace BitTorrent
+{
+    class TorrentBackend final : public QObject
+    {
+        Q_OBJECT
+        Q_DISABLE_COPY_MOVE(TorrentBackend)
+
+    public:
+        TorrentBackend(lt::session *ltSession, lt::torrent_handle ltTorrentHandle, QObject *parent = nullptr);
+
+        void addTrackers(const QList<TrackerEntry> &trackers);
+        void replaceTrackers(const QList<TrackerEntry> &trackers);
+        void addUrlSeeds(const QList<QUrl> &urlSeeds);
+        void removeUrlSeeds(const QList<QUrl> &urlSeeds);
+        void clearPeers();
+        void requestResumeData(lt::resume_data_flags_t flags);
+
+    private:
+        lt::session *m_ltSession;
+        lt::torrent_handle m_ltTorrentHandle;
+    };
+}