cleanup: silence std::move()-related Coverity warnings

Unfortunately Coverity doesn't understand that most Qt data
structures are copy-on-write. It's a mis-feature of Qt, but
it is the way it is. Thus, passing by value is not an issue.

Out of ca. 25 warnings only two were legit. Let's silence
the others by either std::move()ing or passing by reference,
as would be idiomatic C++, which Qt is not.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

commands/command_divelist.cpp

@@ -234,7 +234,7 @@ DivesAndSitesToRemove DiveListBase::addDives(DivesAndTripsToAdd &toAdd)
 	if (!change.newShown.empty() || !change.newHidden.empty())
 		emit diveListNotifier.numShownChanged();
 
-	return { res, sites };
+	return { std::move(res), std::move(sites) };
 }
 
 // This helper function renumbers dives according to an array of id/number pairs.

commands/command_pictures.cpp

@@ -83,7 +83,7 @@ static std::vector<PictureListForAddition> removePictures(std::vector<PictureLis
 		if (!toAdd.pics.empty())
 			res.push_back(toAdd);
 		invalidate_dive_cache(list.d);
-		emit diveListNotifier.picturesRemoved(list.d, filenames);
+		emit diveListNotifier.picturesRemoved(list.d, std::move(filenames));
 	}
 	picturesToRemove.clear();
 	return res;

core/configuredivecomputer.cpp

@@ -65,7 +65,7 @@ static QString writeGasDetails(gas g)
 		}).join(QLatin1Char(','));
 }
 
-bool ConfigureDiveComputer::saveXMLBackup(QString fileName, DeviceDetails *details, device_data_t *data)
+bool ConfigureDiveComputer::saveXMLBackup(const QString &fileName, DeviceDetails *details, device_data_t *data)
 {
 	QString xml = "";
 	QString vendor = data->vendor;
@@ -192,7 +192,7 @@ bool ConfigureDiveComputer::saveXMLBackup(QString fileName, DeviceDetails *detai
 	return true;
 }
 
-bool ConfigureDiveComputer::restoreXMLBackup(QString fileName, DeviceDetails *details)
+bool ConfigureDiveComputer::restoreXMLBackup(const QString &fileName, DeviceDetails *details)
 {
 	QFile file(fileName);
 	if (!file.open(QIODevice::ReadOnly)) {
@@ -491,7 +491,7 @@ bool ConfigureDiveComputer::restoreXMLBackup(QString fileName, DeviceDetails *de
 	return true;
 }
 
-void ConfigureDiveComputer::startFirmwareUpdate(QString fileName, device_data_t *data, bool forceUpdate)
+void ConfigureDiveComputer::startFirmwareUpdate(const QString &fileName, device_data_t *data, bool forceUpdate)
 {
 	setState(FWUPDATE);
 	if (firmwareThread)

core/configuredivecomputer.h

@@ -34,9 +34,9 @@ public:
 	states currentState;
 	void saveDeviceDetails(DeviceDetails *details, device_data_t *data);
 	void fetchDeviceDetails();
-	bool saveXMLBackup(QString fileName, DeviceDetails *details, device_data_t *data);
-	bool restoreXMLBackup(QString fileName, DeviceDetails *details);
-	void startFirmwareUpdate(QString fileName, device_data_t *data, bool forceUpdate);
+	bool saveXMLBackup(const QString &fileName, DeviceDetails *details, device_data_t *data);
+	bool restoreXMLBackup(const QString &fileName, DeviceDetails *details);
+	void startFirmwareUpdate(const QString &fileName, device_data_t *data, bool forceUpdate);
 	void resetSettings(device_data_t *data);
 
 	QString dc_open(device_data_t *data);

core/divefilter.cpp

@@ -145,10 +145,10 @@ bool DiveFilter::showDive(const struct dive *d) const
 void DiveFilter::startFilterDiveSites(QVector<dive_site *> ds)
 {
 	if (++diveSiteRefCount > 1) {
-		setFilterDiveSite(ds);
+		setFilterDiveSite(std::move(ds));
 	} else {
 		std::sort(ds.begin(), ds.end());
-		dive_sites = ds;
+		dive_sites = std::move(ds);
 		// When switching into dive site mode, reload the dive sites.
 		// TODO: why here? why not catch the filterReset signal in the map widget
 #ifdef MAP_SUPPORT
@@ -176,7 +176,7 @@ void DiveFilter::setFilterDiveSite(QVector<dive_site *> ds)
 	std::sort(ds.begin(), ds.end());
 	if (ds == dive_sites)
 		return;
-	dive_sites = ds;
+	dive_sites = std::move(ds);
 
 	emit diveListNotifier.filterReset();
 #ifdef MAP_SUPPORT

core/format.cpp

@@ -33,7 +33,7 @@ enum length_modifier_t {
 };
 
 // Helper function to insert '+' or ' ' after last space
-static QString insert_sign(QString s, char sign)
+static QString insert_sign(const QString &s, char sign)
 {
 	// For space we can take a shortcut: insert in front
 	if (sign == ' ')

core/imagedownloader.cpp

@@ -186,7 +186,7 @@ Thumbnailer::Thumbnail Thumbnailer::getPictureThumbnailFromStream(QDataStream &s
 {
 	QImage res;
 	stream >> res;
-	return { res, MEDIATYPE_PICTURE, zero_duration };
+	return { std::move(res), MEDIATYPE_PICTURE, zero_duration };
 }
 
 void Thumbnailer::markVideoThumbnail(QImage &img)
@@ -362,7 +362,7 @@ void Thumbnailer::frameExtracted(QString filename, QImage thumbnail, duration_t
 		addVideoThumbnailToCache(filename, duration, thumbnail, offset);
 		QMutexLocker l(&lock);
 		workingOn.remove(filename);
-		emit thumbnailChanged(filename, thumbnail, duration);
+		emit thumbnailChanged(filename, std::move(thumbnail), duration);
 	}
 }
 

desktop-widgets/configuredivecomputerdialog.cpp

@@ -267,7 +267,7 @@ ConfigureDiveComputerDialog::ConfigureDiveComputerDialog(QWidget *parent) : QDia
 	settings.endGroup();
 }
 
-OstcFirmwareCheck::OstcFirmwareCheck(QString product) : parent(0)
+OstcFirmwareCheck::OstcFirmwareCheck(const QString &product) : parent(0)
 {
 	QUrl url;
 	memset(&devData, 1, sizeof(devData));

desktop-widgets/configuredivecomputerdialog.h

@@ -123,7 +123,7 @@ private:
 class OstcFirmwareCheck : public QObject {
 	Q_OBJECT
 public:
-	explicit OstcFirmwareCheck(QString product);
+	explicit OstcFirmwareCheck(const QString &product);
 	void checkLatest(QWidget *parent, device_data_t *data);
 public
 slots:

desktop-widgets/divelistview.cpp

@@ -823,7 +823,7 @@ void DiveListView::loadImages()
 	matchImagesToDives(fileNames);
 }
 
-void DiveListView::matchImagesToDives(QStringList fileNames)
+void DiveListView::matchImagesToDives(const QStringList &fileNames)
 {
 	ShiftImageTimesDialog shiftDialog(this, fileNames);
 	shiftDialog.setOffset(lastImageTimeOffset());
@@ -843,9 +843,9 @@ void DiveListView::matchImagesToDives(QStringList fileNames)
 
 		auto it = std::find_if(pics.begin(), pics.end(), [d](const Command::PictureListForAddition &l) { return l.d == d; });
 		if (it == pics.end())
-			pics.push_back(Command::PictureListForAddition { d, { pObj } });
+			pics.push_back(Command::PictureListForAddition { d, { std::move(pObj) } });
 		else
-			it->pics.push_back(pObj);
+			it->pics.push_back(std::move(pObj));
 	}
 
 	if (pics.empty())
@@ -862,7 +862,7 @@ void DiveListView::loadWebImages()
 	loadImagesFromURLs(urlDialog.url());
 }
 
-void DiveListView::loadImagesFromURLs(QString urls)
+void DiveListView::loadImagesFromURLs(const QString &urls)
 {
 	QStringList validUrls;
 	QStringList urlList = urls.split('\n');

desktop-widgets/divelistview.h

@@ -76,8 +76,8 @@ private:
 	void updateLastImageTimeOffset(int offset);
 	int lastImageTimeOffset();
 	void addToTrip(int delta);
-	void matchImagesToDives(QStringList fileNames);
-	void loadImagesFromURLs(QString urls);
+	void matchImagesToDives(const QStringList &fileNames);
+	void loadImagesFromURLs(const QString &urls);
 	bool eventFilter(QObject *, QEvent *) override;
 	void mouseDoubleClickEvent(QMouseEvent *event) override;
 	void contextMenuEvent(QContextMenuEvent *event) override;

desktop-widgets/divelogimportdialog.cpp

@@ -361,7 +361,7 @@ DiveLogImportDialog::DiveLogImportDialog(QStringList fn, QWidget *parent) : QDia
 	ui(new Ui::DiveLogImportDialog)
 {
 	ui->setupUi(this);
-	fileNames = fn;
+	fileNames = std::move(fn);
 	column = 0;
 	delta = "0";
 	hw = "";

desktop-widgets/findmovedimagesdialog.cpp

@@ -94,7 +94,8 @@ struct Dir {
 	double progressFrom, progressTo;
 };
 
-QVector<FindMovedImagesDialog::Match> FindMovedImagesDialog::learnImages(const QString &rootdir, int maxRecursions, QVector<QString> imagePathsIn)
+QVector<FindMovedImagesDialog::Match> FindMovedImagesDialog::learnImages(const QString &rootdir, int maxRecursions,
+									 QVector<QString> imagePathsIn)
 {
 	QMap<QString, ImageMatch> matches;
 
@@ -193,7 +194,7 @@ void FindMovedImagesDialog::on_scanButton_clicked()
 	QFuture<QVector<Match>> future = QtConcurrent::run(
 			// Note that we capture everything but "this" by copy to avoid dangling references.
 			[this, dirName, imagePaths]()
-			{ return learnImages(dirName, 20, imagePaths);}
+			{ return learnImages(dirName, 20, std::move(imagePaths)); }
 	);
 	watcher.setFuture(future);
 }

desktop-widgets/mainwindow.cpp

@@ -1273,7 +1273,7 @@ void MainWindow::setTitle()
 	setWindowTitle("Subsurface: " + displayedFilename(existing_filename) + unsaved + shown);
 }
 
-void MainWindow::importFiles(const QStringList fileNames)
+void MainWindow::importFiles(const QStringList &fileNames)
 {
 	if (fileNames.isEmpty())
 		return;
@@ -1289,7 +1289,7 @@ void MainWindow::importFiles(const QStringList fileNames)
 	Command::importDives(&log, IMPORT_MERGE_ALL_TRIPS, source);
 }
 
-void MainWindow::loadFiles(const QStringList fileNames)
+void MainWindow::loadFiles(const QStringList &fileNames)
 {
 	if (fileNames.isEmpty()) {
 		refreshDisplay();
@@ -1359,7 +1359,7 @@ void MainWindow::on_actionImportDiveLog_triggered()
 	}
 
 	if (csvFiles.size()) {
-		DiveLogImportDialog diveLogImport(csvFiles, this);
+		DiveLogImportDialog diveLogImport(std::move(csvFiles), this);
 		diveLogImport.exec();
 	}
 }

desktop-widgets/mainwindow.h

@@ -67,8 +67,8 @@ public:
 		Count
 	};
 
-	void loadFiles(const QStringList files);
-	void importFiles(const QStringList importFiles);
+	void loadFiles(const QStringList &files);
+	void importFiles(const QStringList &importFiles);
 	void setToolButtonsEnabled(bool enabled);
 	void setApplicationState(ApplicationState state);
 	void enterPreviousState();

desktop-widgets/simplewidgets.cpp

@@ -515,7 +515,7 @@ QString TextHyperlinkEventFilter::tryToFormulateUrl(QTextCursor *cursor)
 		maybeUrlStr = left + right;
 	}
 
-	return stringMeetsOurUrlRequirements(maybeUrlStr) ? maybeUrlStr : QString();
+	return stringMeetsOurUrlRequirements(maybeUrlStr) ? std::move(maybeUrlStr) : QString();
 }
 
 QString TextHyperlinkEventFilter::fromCursorTilWhitespace(QTextCursor *cursor, bool searchBackwards)

desktop-widgets/templatelayout.cpp

@@ -59,7 +59,7 @@ void set_bundled_templates_as_read_only()
 		QFile::setPermissions(pathUser + QDir::separator() + f, QFileDevice::ReadOwner | QFileDevice::ReadUser);
 }
 
-void copy_bundled_templates(QString src, QString dst, QStringList *templateBackupList)
+void copy_bundled_templates(QString src, const QString &dst, QStringList *templateBackupList)
 {
 	QDir dir(src);
 	if (!dir.exists())

desktop-widgets/templatelayout.h

@@ -12,7 +12,7 @@ class QTextStream;
 
 void find_all_templates();
 void set_bundled_templates_as_read_only();
-void copy_bundled_templates(QString src, QString dst, QStringList *templateBackupList);
+void copy_bundled_templates(QString src, const QString &dst, QStringList *templateBackupList);
 
 enum token_t {LITERAL, FORSTART, FORSTOP, BLOCKSTART, BLOCKSTOP, IFSTART, IFSTOP, PARSERERROR};
 

qt-models/divetripmodel.cpp

@@ -179,7 +179,7 @@ static QString displaySac(const struct dive *d, bool units)
 	if (!d->sac)
 		return QString();
 	QString s = get_volume_string(d->sac, units);
-	return units ? s + gettextFromC::tr("/min") : s;
+	return units ? s + gettextFromC::tr("/min") : std::move(s);
 }
 
 static QString displayWeight(const struct dive *d, bool units)

stats/chartlistmodel.cpp

@@ -35,8 +35,8 @@ void ChartListModel::initIcon(ChartSubType type, const char *name, int iconSize)
 	QPixmap iconWarning = icon.copy();
 	QPainter painter(&iconWarning);
 	painter.drawPixmap(0, 0, warningPixmap);
-	subTypeIcons[(size_t)type].normal = icon;
-	subTypeIcons[(size_t)type].warning = iconWarning;
+	subTypeIcons[(size_t)type].normal = std::move(icon);
+	subTypeIcons[(size_t)type].warning = std::move(iconWarning);
 }
 
 const QPixmap &ChartListModel::getIcon(ChartSubType type, bool warning) const

stats/statsvariables.cpp

@@ -271,7 +271,7 @@ QString StatsBinner::formatWithUnit(const StatsBin &bin) const
 {
 	QString unit = unitSymbol();
 	QString name = format(bin);
-	return unit.isEmpty() ? name : QStringLiteral("%1 %2").arg(name, unit);
+	return unit.isEmpty() ? std::move(name) : QStringLiteral("%1 %2").arg(name, unit);
 }
 
 QString StatsBinner::formatLowerBound(const StatsBin &bin) const

stats/statsview.cpp

@@ -710,7 +710,7 @@ static std::vector<QString> makePercentageLabels(int count, int total, bool isHo
 	if (isHorizontal)
 		return { QString("%1 (%2)").arg(countString, percentageString) };
 	else
-		return { countString, percentageString };
+		return { std::move(countString), std::move(percentageString) };
 }
 
 // From a list of dive bins, make (dives, label) pairs, where the label