From 6cd233dd61b75e32917b4e8395abf0cad0f3f953 Mon Sep 17 00:00:00 2001
From: Eugene Shalygin <eugene.shalygin@gmail.com>
Date: Wed, 18 Jan 2017 17:17:51 +0100
Subject: [PATCH 1/2] Add queue repair code

This is a bit adjusted code created by nxd4, who shared it in issue
disappearing).
---
 src/base/bittorrent/session.cpp | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/src/base/bittorrent/session.cpp b/src/base/bittorrent/session.cpp
index 6ef664e6f..3c3716a78 100644
--- a/src/base/bittorrent/session.cpp
+++ b/src/base/bittorrent/session.cpp
@@ -3077,6 +3077,7 @@ void Session::startUpTorrents()
     // Resume downloads
     QMap<int, TorrentResumeData> queuedResumeData;
     int nextQueuePosition = 1;
+    int numOfRemappedFiles = 0;
     QRegExp rx(QLatin1String("^([A-Fa-f0-9]{40})\\.fastresume$"));
     foreach (const QString &fastresumeName, fastresumes) {
         if (rx.indexIn(fastresumeName) == -1) continue;
@@ -3100,11 +3101,23 @@ void Session::startUpTorrents()
                 }
             }
             else {
-                queuedResumeData[queuePosition] = { hash, magnetUri, resumeData, data };
+                int q = queuePosition;
+                for(; queuedResumeData.contains(q); ++q) {
+                }
+                if (q != queuePosition) {
+                    ++numOfRemappedFiles;
+                }
+                queuedResumeData[q] = { hash, magnetUri, resumeData, data };
             }
         }
     }
 
+    if (numOfRemappedFiles > 0) {
+        logger->addMessage(
+            QString(tr("Queue positions were corrected in %1 resume files")).arg(numOfRemappedFiles),
+            Log::CRITICAL);
+    }
+
     // starting up downloading torrents (queue position > 0)
     foreach (const TorrentResumeData &torrentResumeData, queuedResumeData)
         startupTorrent(torrentResumeData);

From b6e64c13d8b2ea7535b593560b6d3a3372701455 Mon Sep 17 00:00:00 2001
From: Eugene Shalygin <eugene.shalygin@gmail.com>
Date: Wed, 18 Jan 2017 17:23:57 +0100
Subject: [PATCH 2/2] Fetch torrent status when generating final fastresume
 data

This is done to get correct queue position, which has to be written into
the fastresume file. See discussion in #6154.
---
 src/base/bittorrent/session.cpp       | 6 +++---
 src/base/bittorrent/session.h         | 2 +-
 src/base/bittorrent/torrenthandle.cpp | 5 ++++-
 src/base/bittorrent/torrenthandle.h   | 2 +-
 4 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/src/base/bittorrent/session.cpp b/src/base/bittorrent/session.cpp
index 3c3716a78..0885819a0 100644
--- a/src/base/bittorrent/session.cpp
+++ b/src/base/bittorrent/session.cpp
@@ -1858,7 +1858,7 @@ void Session::generateResumeData(bool final)
         if (torrent->isChecking() || torrent->hasError()) continue;
         if (!final && !torrent->needSaveResumeData()) continue;
 
-        saveTorrentResumeData(torrent);
+        saveTorrentResumeData(torrent, final);
         qDebug("Saving fastresume data for %s", qPrintable(torrent->name()));
     }
 }
@@ -2782,9 +2782,9 @@ void Session::handleTorrentRatioLimitChanged(TorrentHandle *const torrent)
     updateRatioTimer();
 }
 
-void Session::saveTorrentResumeData(TorrentHandle *const torrent)
+void Session::saveTorrentResumeData(TorrentHandle *const torrent, bool finalSave)
 {
-    torrent->saveResumeData();
+    torrent->saveResumeData(finalSave);
     ++m_numResumeData;
 }
 
diff --git a/src/base/bittorrent/session.h b/src/base/bittorrent/session.h
index 0ec3dc038..32ccbec11 100644
--- a/src/base/bittorrent/session.h
+++ b/src/base/bittorrent/session.h
@@ -467,7 +467,7 @@ namespace BitTorrent
 
         void updateRatioTimer();
         void exportTorrentFile(TorrentHandle *const torrent, TorrentExportFolder folder = TorrentExportFolder::Regular);
-        void saveTorrentResumeData(TorrentHandle *const torrent);
+        void saveTorrentResumeData(TorrentHandle *const torrent, bool finalSave = false);
 
         void handleAlert(libtorrent::alert *a);
         void dispatchTorrentAlert(libtorrent::alert *a);
diff --git a/src/base/bittorrent/torrenthandle.cpp b/src/base/bittorrent/torrenthandle.cpp
index b03bf90af..6e6dfafbd 100644
--- a/src/base/bittorrent/torrenthandle.cpp
+++ b/src/base/bittorrent/torrenthandle.cpp
@@ -485,8 +485,11 @@ bool TorrentHandle::needSaveResumeData() const
     SAFE_RETURN(bool, need_save_resume_data, false);
 }
 
-void TorrentHandle::saveResumeData()
+void TorrentHandle::saveResumeData(bool updateStatus)
 {
+    if (updateStatus) // to update queue_position, see discussion in PR #6154
+        this->updateStatus();
+
     SAFE_CALL(save_resume_data);
     m_needSaveResumeData = false;
 }
diff --git a/src/base/bittorrent/torrenthandle.h b/src/base/bittorrent/torrenthandle.h
index aad66f001..a0837d09f 100644
--- a/src/base/bittorrent/torrenthandle.h
+++ b/src/base/bittorrent/torrenthandle.h
@@ -351,7 +351,7 @@ namespace BitTorrent
         void handleTempPathChanged();
         void handleCategorySavePathChanged();
         void handleAppendExtensionToggled();
-        void saveResumeData();
+        void saveResumeData(bool updateStatus = false);
 
     private:
         typedef boost::function<void ()> EventTrigger;