Make sure files are truncated before writing

src/analysis/interpolation/qgsgridfilewriter.cpp

@@ -48,7 +48,7 @@ int QgsGridFileWriter::writeFile( bool showProgressDialog )
 {
   QFile outputFile( mOutputFilePath );
 
-  if ( !outputFile.open( QFile::WriteOnly ) )
+  if ( !outputFile.open( QFile::WriteOnly | QIODevice::Truncate ) )
   {
     return 1;
   }
@@ -111,7 +111,7 @@ int QgsGridFileWriter::writeFile( bool showProgressDialog )
   QFileInfo fi( mOutputFilePath );
   QString fileName = fi.absolutePath() + '/' + fi.completeBaseName() + ".prj";
   QFile prjFile( fileName );
-  if ( !prjFile.open( QFile::WriteOnly ) )
+  if ( !prjFile.open( QFile::WriteOnly | QIODevice::Truncate ) )
   {
     return 1;
   }

src/analysis/raster/qgsrelief.cpp

@@ -574,7 +574,7 @@ bool QgsRelief::exportFrequencyDistributionToCsv( const QString& file )
 
   //write out frequency values to csv file for debugging
   QFile outFile( file );
-  if ( !outFile.open( QIODevice::WriteOnly ) )
+  if ( !outFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     return false;
   }

src/app/composer/qgscomposer.cpp

@@ -2877,7 +2877,7 @@ void QgsComposer::exportCompositionAsSVG( QgsComposer::OutputMode mode )
         QFileInfo fi( outputFileName );
         QString currentFileName = i == 0 ? outputFileName : fi.absolutePath() + '/' + fi.baseName() + '_' + QString::number( i + 1 ) + '.' + fi.suffix();
         QFile out( currentFileName );
-        bool openOk = out.open( QIODevice::WriteOnly | QIODevice::Text );
+        bool openOk = out.open( QIODevice::WriteOnly | QIODevice::Text | QIODevice::Truncate );
         if ( !openOk )
         {
           QMessageBox::warning( this, tr( "SVG export error" ),
@@ -3099,7 +3099,7 @@ void QgsComposer::on_mActionSaveAsTemplate_triggered()
   settings.setValue( "UI/lastComposerTemplateDir", saveFileInfo.absolutePath() );
 
   QFile templateFile( saveFileName );
-  if ( !templateFile.open( QIODevice::WriteOnly ) )
+  if ( !templateFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     return;
   }
@@ -4068,7 +4068,7 @@ void QgsComposer::createComposerView()
 void QgsComposer::writeWorldFile( const QString& worldFileName, double a, double b, double c, double d, double e, double f ) const
 {
   QFile worldFile( worldFileName );
-  if ( !worldFile.open( QIODevice::WriteOnly | QIODevice::Text ) )
+  if ( !worldFile.open( QIODevice::WriteOnly | QIODevice::Text | QIODevice::Truncate ) )
   {
     return;
   }

src/app/main.cpp

@@ -1229,7 +1229,7 @@ int main( int argc, char *argv[] )
     QFile dxfFile;
     if ( dxfOutputFile == "-" )
     {
-      if ( !dxfFile.open( stdout, QIODevice::WriteOnly ) )
+      if ( !dxfFile.open( stdout, QIODevice::WriteOnly | QIODevice::Truncate ) )
       {
         std::cerr << "could not open stdout" << std::endl;
         return 2;

src/app/qgsbookmarks.cpp

@@ -372,7 +372,7 @@ void QgsBookmarks::exportToXml()
   }
 
   QFile f( fileName );
-  if ( !f.open( QFile::WriteOnly ) )
+  if ( !f.open( QFile::WriteOnly | QIODevice::Truncate ) )
   {
     f.close();
     return;

src/app/qgsrasterlayerproperties.cpp

@@ -1281,7 +1281,7 @@ void QgsRasterLayerProperties::on_pbnExportTransparentPixelValues_clicked()
     }
 
     QFile myOutputFile( myFileName );
-    if ( myOutputFile.open( QFile::WriteOnly ) )
+    if ( myOutputFile.open( QFile::WriteOnly | QIODevice::Truncate ) )
     {
       QTextStream myOutputStream( &myOutputFile );
       myOutputStream << "# " << tr( "QGIS Generated Transparent Pixel Value Export File" ) << '\n';

src/app/qgssubstitutionlistwidget.cpp

@@ -107,7 +107,7 @@ void QgsSubstitutionListWidget::on_mButtonExport_clicked()
   doc.appendChild( root );
 
   QFile file( fileName );
-  if ( !file.open( QIODevice::WriteOnly | QIODevice::Text ) )
+  if ( !file.open( QIODevice::WriteOnly | QIODevice::Text | QIODevice::Truncate ) )
   {
     QMessageBox::warning( nullptr, tr( "Export substitutions" ),
                           tr( "Cannot write file %1:\n%2." ).arg( fileName, file.errorString() ),

src/core/auth/qgsauthcertutils.cpp

@@ -253,7 +253,7 @@ QString QgsAuthCertUtils::pemTextToTempFile( const QString &name, const QByteArr
   QFile pemFile( QDir::tempPath() + QDir::separator() + name );
   QString pemFilePath( pemFile.fileName() );
 
-  if ( pemFile.open( QIODevice::WriteOnly ) )
+  if ( pemFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     qint64 bytesWritten = pemFile.write( pemtext );
     if ( bytesWritten == -1 )

src/core/qgsapplication.cpp

@@ -494,7 +494,7 @@ void QgsApplication::setUITheme( const QString &themeName )
 
   if ( variableInfo.exists() && variablesfile.open( QIODevice::ReadOnly ) )
   {
-    if ( !file.open( QIODevice::ReadOnly ) || !fileout.open( QIODevice::WriteOnly | QIODevice::Text ) )
+    if ( !file.open( QIODevice::ReadOnly ) || !fileout.open( QIODevice::WriteOnly | QIODevice::Text | QIODevice::Truncate ) )
     {
       return;
     }

src/core/qgsrenderchecker.cpp

@@ -230,7 +230,7 @@ bool QgsRenderChecker::runTest( const QString& theTestName,
   //create a world file to go with the image...
 
   QFile wldFile( QDir::tempPath() + '/' + theTestName + "_result.wld" );
-  if ( wldFile.open( QIODevice::WriteOnly ) )
+  if ( wldFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     QgsRectangle r = mMapSettings.extent();
 

src/core/qgsscaleutils.cpp

@@ -34,7 +34,7 @@ bool QgsScaleUtils::saveScaleList( const QString &fileName, const QStringList &s
   }
 
   QFile file( fileName );
-  if ( !file.open( QIODevice::WriteOnly | QIODevice::Text ) )
+  if ( !file.open( QIODevice::WriteOnly | QIODevice::Text | QIODevice::Truncate ) )
   {
     errorMessage = QString( "Cannot write file %1:\n%2." ).arg( fileName, file.errorString() );
     return false;

src/core/qgsvectorfilewriter.cpp

@@ -363,7 +363,7 @@ void QgsVectorFileWriter::init( QString vectorFileName,
     {
       QString layerName = vectorFileName.left( vectorFileName.indexOf( ".shp", Qt::CaseInsensitive ) );
       QFile prjFile( layerName + ".qpj" );
-      if ( prjFile.open( QIODevice::WriteOnly ) )
+      if ( prjFile.open( QIODevice::WriteOnly  | QIODevice::Truncate ) )
       {
         QTextStream prjStream( &prjFile );
         prjStream << srs.toWkt().toLocal8Bit().constData() << endl;

src/core/symbology-ng/qgsstyle.cpp

@@ -1388,7 +1388,7 @@ bool QgsStyle::exportXml( const QString& filename )
 
   // save
   QFile f( filename );
-  if ( !f.open( QFile::WriteOnly ) )
+  if ( !f.open( QFile::WriteOnly | QIODevice::Truncate ) )
   {
     mErrorString = "Couldn't open file for writing: " + filename;
     return false;

src/core/symbology-ng/qgssymbollayerutils.cpp

@@ -2950,7 +2950,7 @@ QMimeData* QgsSymbolLayerUtils::colorListToMimeData( const QgsNamedColorList& co
 
 bool QgsSymbolLayerUtils::saveColorsToGpl( QFile &file, const QString& paletteName, const QgsNamedColorList& colors )
 {
-  if ( !file.open( QIODevice::ReadWrite ) )
+  if ( !file.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     return false;
   }

src/gui/qgsconfigureshortcutsdialog.cpp

@@ -139,7 +139,7 @@ void QgsConfigureShortcutsDialog::saveShortcuts()
   }
 
   QFile file( fileName );
-  if ( !file.open( QIODevice::WriteOnly | QIODevice::Text ) )
+  if ( !file.open( QIODevice::WriteOnly | QIODevice::Text | QIODevice::Truncate ) )
   {
     QMessageBox::warning( this, tr( "Saving shortcuts" ),
                           tr( "Cannot write file %1:\n%2." )

src/gui/qgsmanageconnectionsdialog.cpp

@@ -133,7 +133,7 @@ void QgsManageConnectionsDialog::doExportImport()
     }
 
     QFile file( mFileName );
-    if ( !file.open( QIODevice::WriteOnly | QIODevice::Text ) )
+    if ( !file.open( QIODevice::WriteOnly | QIODevice::Text | QIODevice::Truncate ) )
     {
       QMessageBox::warning( this, tr( "Saving connections" ),
                             tr( "Cannot write file %1:\n%2." )

src/gui/qgsmapcanvas.cpp

@@ -782,7 +782,7 @@ void QgsMapCanvas::saveAsImage( const QString& theFileName, QPixmap * theQPixmap
   QString myWorldFileName = myInfo.absolutePath() + '/' + myInfo.baseName() + '.'
                             + outputSuffix.at( 0 ) + outputSuffix.at( myInfo.suffix().size() - 1 ) + 'w';
   QFile myWorldFile( myWorldFileName );
-  if ( !myWorldFile.open( QIODevice::WriteOnly ) ) //don't use QIODevice::Text
+  if ( !myWorldFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) ) //don't use QIODevice::Text
   {
     return;
   }

src/gui/qgssearchquerybuilder.cpp

@@ -379,7 +379,7 @@ void QgsSearchQueryBuilder::saveQuery()
   }
 
   QFile saveFile( saveFileName );
-  if ( !saveFile.open( QIODevice::WriteOnly ) )
+  if ( !saveFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     QMessageBox::critical( nullptr, tr( "Error" ), tr( "Could not open file for writing" ) );
     return;

src/gui/raster/qgsrastertransparencywidget.cpp

@@ -251,7 +251,7 @@ void QgsRasterTransparencyWidget::on_pbnExportTransparentPixelValues_clicked()
     }
 
     QFile myOutputFile( myFileName );
-    if ( myOutputFile.open( QFile::WriteOnly ) )
+    if ( myOutputFile.open( QFile::WriteOnly | QIODevice::Truncate ) )
     {
       QTextStream myOutputStream( &myOutputFile );
       myOutputStream << "# " << tr( "QGIS Generated Transparent Pixel Value Export File" ) << '\n';

src/gui/raster/qgssinglebandpseudocolorrendererwidget.cpp

@@ -670,7 +670,7 @@ void QgsSingleBandPseudoColorRendererWidget::on_mExportToFileButton_clicked()
     }
 
     QFile outputFile( fileName );
-    if ( outputFile.open( QFile::WriteOnly ) )
+    if ( outputFile.open( QFile::WriteOnly | QIODevice::Truncate ) )
     {
       QTextStream outputStream( &outputFile );
       outputStream << "# " << tr( "QGIS Generated Color Map Export File" ) << '\n';

src/plugins/georeferencer/qgsgeorefplugingui.cpp

@@ -1280,7 +1280,7 @@ bool QgsGeorefPluginGui::loadGCPs( /*bool verbose*/ )
 void QgsGeorefPluginGui::saveGCPs()
 {
   QFile pointFile( mGCPpointsFileName );
-  if ( pointFile.open( QIODevice::WriteOnly ) )
+  if ( pointFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     QTextStream points( &pointFile );
     points << "mapX,mapY,pixelX,pixelY,enable" << endl;
@@ -1422,7 +1422,7 @@ bool QgsGeorefPluginGui::writeWorldFile( const QgsPoint& origin, double pixelXSi
 {
   // write the world file
   QFile file( mWorldFileName );
-  if ( !file.open( QIODevice::WriteOnly ) )
+  if ( !file.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     mMessageBar->pushMessage( tr( "Error" ), tr( "Could not write to %1." ).arg( mWorldFileName ), QgsMessageBar::CRITICAL, messageTimeout() );
     return false;

src/plugins/grass/qgsgrassmapcalc.cpp

@@ -1052,7 +1052,7 @@ void QgsGrassMapcalc::save()
                  + "/mapcalc/" + mFileName;
 
   QFile out( path );
-  if ( !out.open( QIODevice::WriteOnly ) )
+  if ( !out.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     QMessageBox::warning( this, tr( "Save mapcalc" ),
                           tr( "Cannot open mapcalc file" ) );

src/plugins/raster_terrain_analysis/qgsrasterterrainanalysisdialog.cpp

@@ -249,7 +249,7 @@ void QgsRasterTerrainAnalysisDialog::on_mExportColorsButton_clicked()
   }
 
   QFile outputFile( file );
-  if ( !outputFile.open( QIODevice::WriteOnly ) )
+  if ( !outputFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     return;
   }

src/providers/gpx/qgsgpxprovider.cpp

@@ -203,7 +203,7 @@ bool QgsGPXProvider::addFeatures( QgsFeatureList & flist )
 
   // write back to file
   QFile file( mFileName );
-  if ( !file.open( QIODevice::WriteOnly ) )
+  if ( !file.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
     return false;
   QTextStream ostr( &file );
   data->writeXml( ostr );
@@ -391,7 +391,7 @@ bool QgsGPXProvider::deleteFeatures( const QgsFeatureIds & id )
 
   // write back to file
   QFile file( mFileName );
-  if ( !file.open( QIODevice::WriteOnly ) )
+  if ( !file.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
     return false;
   QTextStream ostr( &file );
   data->writeXml( ostr );
@@ -441,7 +441,7 @@ bool QgsGPXProvider::changeAttributeValues( const QgsChangedAttributesMap &attr_
 
   // write back to file
   QFile file( mFileName );
-  if ( !file.open( QIODevice::WriteOnly ) )
+  if ( !file.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
     return false;
   QTextStream ostr( &file );
   data->writeXml( ostr );

src/providers/ogr/qgsogrdataitems.cpp

@@ -74,7 +74,7 @@ bool QgsOgrLayerItem::setCrs( QgsCoordinateReferenceSystem crs )
   char* pszOutWkt = nullptr;
   OSRExportToWkt( hSRS, &pszOutWkt );
   QFile prjFile( layerName + ".prj" );
-  if ( prjFile.open( QIODevice::WriteOnly ) )
+  if ( prjFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     QTextStream prjStream( &prjFile );
     prjStream << pszOutWkt << endl;
@@ -90,7 +90,7 @@ bool QgsOgrLayerItem::setCrs( QgsCoordinateReferenceSystem crs )
 
   // save qgis-specific .qpj file (maybe because of better wkt compatibility?)
   QFile qpjFile( layerName + ".qpj" );
-  if ( qpjFile.open( QIODevice::WriteOnly ) )
+  if ( qpjFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     QTextStream qpjStream( &qpjFile );
     qpjStream << wkt.toLocal8Bit().data() << endl;

src/providers/ogr/qgsogrprovider.cpp

@@ -2663,7 +2663,7 @@ QGISEXTERN bool createEmptyDataSource( const QString &uri,
   {
     QString layerName = uri.left( uri.indexOf( ".shp", Qt::CaseInsensitive ) );
     QFile prjFile( layerName + ".qpj" );
-    if ( prjFile.open( QIODevice::WriteOnly ) )
+    if ( prjFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
     {
       QTextStream prjStream( &prjFile );
       prjStream << myWkt.toLocal8Bit().data() << endl;

src/providers/wcs/qgswcscapabilities.cpp

@@ -427,7 +427,7 @@ bool QgsWcsCapabilities::parseCapabilitiesDom( QByteArray const &xml, QgsWcsCapa
   QgsDebugMsg( "Entered." );
 #ifdef QGISDEBUG
   QFile file( QDir::tempPath() + "/qgis-wcs-capabilities.xml" );
-  if ( file.open( QIODevice::WriteOnly ) )
+  if ( file.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     file.write( xml );
     file.close();

src/providers/wfs/qgswfsfeatureiterator.cpp

@@ -904,7 +904,7 @@ void QgsWFSFeatureIterator::featureReceivedSynchronous( QVector<QgsWFSFeatureGml
     mWriterFilename = QDir( QgsWFSUtils::acquireCacheDirectory() ).filePath( QString( "iterator_%1_%2.bin" ).arg( thisStr ).arg( mCounter ) );
     QgsDebugMsg( QString( "Transferring feature iterator cache to %1" ).arg( mWriterFilename ) );
     mWriterFile = new QFile( mWriterFilename );
-    if ( !mWriterFile->open( QIODevice::WriteOnly ) )
+    if ( !mWriterFile->open( QIODevice::WriteOnly | QIODevice::Truncate ) )
     {
       QgsDebugMsg( QString( "Cannot open %1 for writing" ).arg( mWriterFilename ) );
       delete mWriterFile;

src/providers/wfs/qgswfsshareddata.cpp

@@ -354,7 +354,7 @@ bool QgsWFSSharedData::createCache()
 
     // Copy the in-memory template Spatialite DB into the target DB
     QFile dbFile( mCacheDbname );
-    if ( !dbFile.open( QIODevice::WriteOnly ) )
+    if ( !dbFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
     {
       QgsMessageLog::logMessage( tr( "Cannot create temporary SpatiaLite cache" ), tr( "WFS" ) );
       return false;

src/providers/wms/qgswmscapabilities.cpp

@@ -249,7 +249,7 @@ bool QgsWmsCapabilities::parseCapabilitiesDom( QByteArray const &xml, QgsWmsCapa
 
 #ifdef QGISDEBUG
   QFile file( QDir::tempPath() + "/qgis-wmsprovider-capabilities.xml" );
-  if ( file.open( QIODevice::WriteOnly ) )
+  if ( file.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
   {
     file.write( xml );
     file.close();

src/providers/wms/qgswmsprovider.cpp

@@ -3835,7 +3835,7 @@ void QgsWmsTiledImageDownloadHandler::tileReplyFinished()
                                    .arg( reply->url().toString() ), tr( "WMS" ) );
 #ifdef QGISDEBUG
         QFile file( QDir::tempPath() + "/broken-image.png" );
-        if ( file.open( QIODevice::WriteOnly ) )
+        if ( file.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
         {
           file.write( text );
           file.close();

src/server/qgsmsutils.cpp

@@ -70,7 +70,7 @@ QString QgsMSUtils::createTempFilePath()