From 7fc7925d17df58e6dfb9eb1383f0895d5fadce58 Mon Sep 17 00:00:00 2001
From: Markus Goetz <markus@woboq.com>
Date: Thu, 30 Jul 2015 14:32:33 +0200
Subject: [PATCH] Propagator: Don't corrupt file with broken webserver #3373

---
 src/libsync/propagatedownload.cpp | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/libsync/propagatedownload.cpp b/src/libsync/propagatedownload.cpp
index c97f19a88b6..e1e4ed48951 100644
--- a/src/libsync/propagatedownload.cpp
+++ b/src/libsync/propagatedownload.cpp
@@ -490,6 +490,15 @@ void PropagateDownloadFileQNAM::slotGetFinished()
     const QByteArray sizeHeader("Content-Length");
     quint64 bodySize = job->reply()->rawHeader(sizeHeader).toULongLong();
 
+    if (!job->reply()->rawHeader(sizeHeader).isEmpty() && _tmpFile.size() > 0 && bodySize == 0) {
+        // Strange bug with broken webserver or webfirewall https://github.com/owncloud/client/issues/3373#issuecomment-122672322
+        // This happened when trying to resume a file. The Content-Range header was files, Content-Length was == 0
+        qDebug() << bodySize << _item->_size << _tmpFile.size() << job->resumeStart();
+        _tmpFile.remove();
+        done(SyncFileItem::NormalError, QLatin1String("Broken webserver returning empty content length for non-empty file on resume"));
+        return;
+    }
+
     if(bodySize > 0 && bodySize != _tmpFile.size() - job->resumeStart() ) {
         qDebug() << bodySize << _tmpFile.size() << job->resumeStart();
         _propagator->_anotherSyncNeeded = true;