Warn if we detect that all fles are about to be removed.

src/mirall/csyncthread.cpp

@@ -191,6 +191,11 @@ int CSyncThread::treewalkFile( TREE_WALK_FILE *file, bool remote )
 
     int re = 0;
 
+    if (file->instruction != CSYNC_INSTRUCTION_IGNORE
+        && file->instruction != CSYNC_INSTRUCTION_REMOVE) {
+      _hasFiles = true;
+    }
+
     switch(file->instruction) {
     case CSYNC_INSTRUCTION_NONE:
     case CSYNC_INSTRUCTION_IGNORE:
@@ -327,6 +332,7 @@ void CSyncThread::startSync()
         return;
     }
 
+    _hasFiles = false;
     bool walkOk = true;
     if( csync_walk_local_tree(_csync_ctx, &treewalkLocal, 0) < 0 ) {
         qDebug() << "Error in local treewalk.";
@@ -336,6 +342,16 @@ void CSyncThread::startSync()
         qDebug() << "Error in remote treewalk.";
     }
 
+    if (!_hasFiles && !_syncedItems.isEmpty()) {
+        qDebug() << Q_FUNC_INFO << "All the files are going to be removed, asking the user";
+        bool cancel = true;
+        emit aboutToRemoveAllFiles(&cancel);
+        if (cancel) {
+            qDebug() << Q_FUNC_INFO << "Abort sync";
+            return;
+        }
+    }
+
     if (_needsUpdate)
         emit(started());
 

src/mirall/csyncthread.h

@@ -56,6 +56,8 @@ signals:
     void finished();
     void started();
 
+    void aboutToRemoveAllFiles(bool *cancel);
+
 private:
     void handleSyncError(CSYNC *ctx, const char *state);
     static void progress(const char *remote_url,
@@ -79,6 +81,8 @@ private:
     CSYNC *_csync_ctx;
     bool _needsUpdate;
 
+    bool _hasFiles; // true if there is at least one file that is not ignored or removed
+
     friend class CSyncRunScopeHelper;
 };
 }

src/mirall/owncloudfolder.cpp

@@ -33,6 +33,7 @@
 #include <QNetworkProxy>
 #include <QNetworkAccessManager>
 #include <QNetworkProxyFactory>
+#include <QMessageBox>
 
 namespace Mirall {
 
@@ -290,6 +291,10 @@ void ownCloudFolder::startSync(const QStringList &pathList)
     connect(_csync, SIGNAL(finished()), SLOT(slotCSyncFinished()), Qt::QueuedConnection);
     connect(_csync, SIGNAL(csyncError(QString)), SLOT(slotCSyncError(QString)), Qt::QueuedConnection);
     connect(_csync, SIGNAL(csyncUnavailable()), SLOT(slotCsyncUnavailable()), Qt::QueuedConnection);
+
+    //blocking connection so the message box happens in this thread, but block the csync thread.
+    connect(_csync, SIGNAL(aboutToRemoveAllFiles(bool*)), SLOT(slotAboutToRemoveAllFiles(bool*)), Qt::BlockingQueuedConnection);
+
     _thread->start();
     QMetaObject::invokeMethod(_csync, "startSync", Qt::QueuedConnection);
     emit syncStarted();
@@ -488,5 +493,17 @@ void ServerActionNotifier::slotSyncFinished(const SyncResult &result)
     }
 }
 
+void ownCloudFolder::slotAboutToRemoveAllFiles(bool *cancel)
+{
+    QMessageBox::StandardButton ret = QMessageBox::warning(0,
+        tr("All files removed"),
+        tr("The sync operation is about to remove all the file in the current folder."
+            "Do you want to continue and remove all the files?"),
+         QMessageBox::Ok| QMessageBox::Abort, QMessageBox::Ok);
+
+    *cancel = (ret == QMessageBox::Abort);
+}
+
+
 } // ns
 

src/mirall/owncloudfolder.h

@@ -77,6 +77,7 @@ public:
 public slots:
     void startSync();
     void slotTerminateSync();
+    void slotAboutToRemoveAllFiles(bool*);
 
 protected slots:
     void slotLocalPathChanged( const QString& );