Fix #181

This moves the allocation of the LogDataOperation slightly down, since
we now only enqueue the operation conditionally.

src/data/logdata.cpp

@@ -202,33 +202,35 @@ void LogData::fileChangedOnDisk()
     const QString name = attached_file_->fileName();
     QFileInfo info( name );
 
-    // Need to open the file in case it was absent
-    attached_file_->open( QIODevice::ReadOnly );
-
-    std::shared_ptr<LogDataOperation> newOperation;
+    std::function<std::shared_ptr<LogDataOperation>()> newOperation;
 
     qint64 file_size = indexing_data_.getSize();
     LOG(logDEBUG) << "current fileSize=" << file_size;
     LOG(logDEBUG) << "info file_->size()=" << info.size();
     if ( info.size() < file_size ) {
         fileChangedOnDisk_ = Truncated;
         LOG(logINFO) << "File truncated";
-        newOperation = std::make_shared<FullIndexOperation>();
+        newOperation = std::make_shared<FullIndexOperation>;
     }
     else if ( info.size() == file_size ) {
         LOG(logINFO) << "No change in file";
     }
     else if ( fileChangedOnDisk_ != DataAdded ) {
         fileChangedOnDisk_ = DataAdded;
         LOG(logINFO) << "New data on disk";
-        newOperation = std::make_shared<PartialIndexOperation>();
+        newOperation = std::make_shared<PartialIndexOperation>;
     }
 
     if ( newOperation ) {
-        enqueueOperation( newOperation );
-        lastModifiedDate_ = info.lastModified();
+        // Need to open the file in case it was absent
+        attached_file_->close();
+
+        if ( attached_file_->open( QIODevice::ReadOnly ) ) {
+            enqueueOperation( newOperation() );
+            lastModifiedDate_ = info.lastModified();
 
-        emit fileChanged( fileChangedOnDisk_ );
+            emit fileChanged( fileChangedOnDisk_ );
+        }
     }
 }