Get rid of pointers to dive structures in the UI

The assumption that the pointer will keep pointing to a valid structure is
fundamentally flawed. And even if that is true today, it might change in
the future - just don't do it. Use the diveId instead.

The exception is when you own the structure and use it within one UI
interaction during which any way to change the dive_table is disabled
(e.g., while adding / editing a dive).

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

qt-ui/models.cpp

@@ -62,7 +62,7 @@ void CleanerTableModel::setHeaderDataStrings(const QStringList& newHeaders)
 	headers = newHeaders;
 }
 
-CylindersModel::CylindersModel(QObject* parent): current(0), rows(0)
+CylindersModel::CylindersModel(QObject* parent): currentId(0), rows(0)
 {
 	//	enum{REMOVE, TYPE, SIZE, WORKINGPRESS, START, END, O2, HE, DEPTH};
 	setHeaderDataStrings( QStringList() <<  "" << tr("Type") << tr("Size") << tr("WorkPress") << tr("StartPress") << tr("EndPress") <<  trUtf8("O" UTF8_SUBSCRIPT_2 "%") << tr("He%") << tr("Switch at"));
@@ -90,6 +90,8 @@ QVariant CylindersModel::data(const QModelIndex& index, int role) const
 	if (!index.isValid() || index.row() >= MAX_CYLINDERS)
 		return ret;
 
+	struct dive *current = getDiveById(currentId);
+	Q_ASSERT(current != NULL);
 	cylinder_t *cyl = &current->cylinder[index.row()];
 	switch (role) {
 	case Qt::FontRole: {
@@ -157,6 +159,8 @@ QVariant CylindersModel::data(const QModelIndex& index, int role) const
 
 cylinder_t* CylindersModel::cylinderAt(const QModelIndex& index)
 {
+	struct dive *current = getDiveById(currentId);
+	Q_ASSERT(current != NULL);
 	return &current->cylinder[index.row()];
 }
 
@@ -314,6 +318,8 @@ void CylindersModel::add()
 	}
 
 	int row = rows;
+	struct dive *current = getDiveById(currentId);
+	Q_ASSERT(current != NULL);
 	fill_default_cylinder(&current->cylinder[row]);
 	beginInsertRows(QModelIndex(), row, row);
 	rows++;
@@ -323,6 +329,8 @@ void CylindersModel::add()
 
 void CylindersModel::update()
 {
+	struct dive *current = getDiveById(currentId);
+	Q_ASSERT(current != NULL);
 	setDive(current);
 }
 
@@ -336,6 +344,7 @@ void CylindersModel::clear()
 
 void CylindersModel::setDive(dive* d)
 {
+	struct dive *current = getDiveById(currentId);
 	if (current)
 		clear();
 	if (!d)
@@ -346,7 +355,7 @@ void CylindersModel::setDive(dive* d)
 			rows = i+1;
 		}
 	}
-	current = d;
+	currentId = d->id;
 	changed = false;
 	if (rows > 0) {
 		beginInsertRows(QModelIndex(), 0, rows-1);
@@ -366,6 +375,8 @@ void CylindersModel::remove(const QModelIndex& index)
 	if (index.column() != REMOVE) {
 		return;
 	}
+	struct dive *current = getDiveById(currentId);
+	Q_ASSERT(current != NULL);
 	cylinder_t *cyl = &current->cylinder[index.row()];
 	if (DivePlannerPointsModel::instance()->tankInUse(cyl->gasmix.o2.permille, cyl->gasmix.he.permille)) {
 		QMessageBox::warning(mainWindow(), TITLE_OR_TEXT(
@@ -381,7 +392,7 @@ void CylindersModel::remove(const QModelIndex& index)
 	endRemoveRows();
 }
 
-WeightModel::WeightModel(QObject* parent): current(0), rows(0)
+WeightModel::WeightModel(QObject* parent): currentId(0), rows(0)
 {
 	//enum Column {REMOVE, TYPE, WEIGHT};
 	setHeaderDataStrings(QStringList() << tr("") << tr("Type") << tr("Weight"));
@@ -389,6 +400,8 @@ WeightModel::WeightModel(QObject* parent): current(0), rows(0)
 
 weightsystem_t* WeightModel::weightSystemAt(const QModelIndex& index)
 {
+	struct dive *current = getDiveById(currentId);
+	Q_ASSERT(current != NULL);
 	return &current->weightsystem[index.row()];
 }
 
@@ -397,6 +410,8 @@ void WeightModel::remove(const QModelIndex& index)
 	if (index.column() != REMOVE) {
 		return;
 	}
+	struct dive *current = getDiveById(currentId);
+	Q_ASSERT(current != NULL);
 	beginRemoveRows(QModelIndex(), index.row(), index.row()); // yah, know, ugly.
 	rows--;
 	remove_weightsystem(current, index.row());
@@ -418,6 +433,8 @@ QVariant WeightModel::data(const QModelIndex& index, int role) const
 	if (!index.isValid() || index.row() >= MAX_WEIGHTSYSTEMS)
 		return ret;
 
+	struct dive *current = getDiveById(currentId);
+	Q_ASSERT(current != NULL);
 	weightsystem_t *ws = &current->weightsystem[index.row()];
 
 	switch (role) {
@@ -455,6 +472,8 @@ QVariant WeightModel::data(const QModelIndex& index, int role) const
 // so we only implement the two columns we care about
 void WeightModel::passInData(const QModelIndex& index, const QVariant& value)
 {
+	struct dive *current = getDiveById(currentId);
+	Q_ASSERT(current != NULL);
 	weightsystem_t *ws = &current->weightsystem[index.row()];
 	if (index.column() == WEIGHT) {
 		if (ws->weight.grams != value.toInt()) {
@@ -488,6 +507,8 @@ lbs:
 bool WeightModel::setData(const QModelIndex& index, const QVariant& value, int role)
 {
 	QString vString = value.toString();
+	struct dive *current = getDiveById(currentId);
+	Q_ASSERT(current != NULL);
 	weightsystem_t *ws = &current->weightsystem[index.row()];
 	switch(index.column()) {
 	case TYPE:
@@ -549,11 +570,14 @@ void WeightModel::add()
 
 void WeightModel::update()
 {
+	struct dive *current = getDiveById(currentId);
+	Q_ASSERT(current != NULL);
 	setDive(current);
 }
 
 void WeightModel::setDive(dive* d)
 {
+	struct dive *current = getDiveById(currentId);
 	if (current)
 		clear();
 	rows = 0;
@@ -562,7 +586,7 @@ void WeightModel::setDive(dive* d)
 			rows = i+1;
 		}
 	}
-	current = d;
+	currentId = d->id;
 	changed = false;
 	if (rows > 0) {
 		beginInsertRows(QModelIndex(), 0, rows-1);
@@ -960,6 +984,8 @@ static int nitrox_sort_value(struct dive *dive)
 QVariant DiveItem::data(int column, int role) const
 {
 	QVariant retVal;
+	struct dive *dive = getDiveById(diveId);
+	Q_ASSERT(dive != NULL);
 
 	switch (role) {
 	case Qt::TextAlignmentRole:
@@ -1048,21 +1074,26 @@ bool DiveItem::setData(const QModelIndex& index, const QVariant& value, int role
 		if (d->number == v)
 			return false;
 	}
-
-	dive->number = value.toInt();
+	d = getDiveById(diveId);
+	Q_ASSERT(d != NULL);
+	d->number = value.toInt();
 	mark_divelist_changed(TRUE);
 	return true;
 }
 
 QString DiveItem::displayDate() const
 {
+	struct dive *dive = getDiveById(diveId);
+	Q_ASSERT(dive != NULL);
 	return get_dive_date_string(dive->when);
 }
 
 QString DiveItem::displayDepth() const
 {
-	const int scale = 1000;
 	QString fract, str;
+	const int scale = 1000;
+	struct dive *dive = getDiveById(diveId);
+	Q_ASSERT(dive != NULL);
 	if (get_units()->length == units::METERS) {
 		fract = QString::number((unsigned)(dive->maxdepth.mm % scale) / 100);
 		str = QString("%1.%2").arg((unsigned)(dive->maxdepth.mm / scale)).arg(fract, 1, QChar('0'));
@@ -1076,6 +1107,8 @@ QString DiveItem::displayDepth() const
 QString DiveItem::displayDuration() const
 {
 	int hrs, mins, secs;
+	struct dive *dive = getDiveById(diveId);
+	Q_ASSERT(dive != NULL);
 	secs = dive->duration.seconds % 60;
 	mins = dive->duration.seconds / 60;
 	hrs = mins / 60;
@@ -1093,6 +1126,8 @@ QString DiveItem::displayDuration() const
 QString DiveItem::displayTemperature() const
 {
 	QString str;
+	struct dive *dive = getDiveById(diveId);
+	Q_ASSERT(dive != NULL);
 	if (!dive->watertemp.mkelvin)
 		return str;
 	if (get_units()->temperature == units::CELSIUS)
@@ -1105,6 +1140,8 @@ QString DiveItem::displayTemperature() const
 QString DiveItem::displaySac() const
 {
 	QString str;
+	struct dive *dive = getDiveById(diveId);
+	Q_ASSERT(dive != NULL);
 	if (get_units()->volume == units::LITER)
 		str = QString::number(dive->sac / 1000.0, 'f', 1).append(tr(" l/min"));
 	else
@@ -1120,6 +1157,8 @@ QString DiveItem::displayWeight() const
 
 int DiveItem::weight() const
 {
+	struct dive *dive = getDiveById(diveId);
+	Q_ASSERT(dive != 0);
 	weight_t tw = { total_weight(dive) };
 	return tw.grams;
 }
@@ -1187,7 +1226,7 @@ void DiveTripModel::setupModelData()
 		dive_trip_t* trip = dive->divetrip;
 
 		DiveItem* diveItem = new DiveItem();
-		diveItem->dive = dive;
+		diveItem->diveId = dive->id;
 
 		if (!trip || currentLayout == LIST) {
 			diveItem->parent = rootItem;
@@ -1594,7 +1633,7 @@ ProfilePrintModel::ProfilePrintModel(QObject *parent)
 
 void ProfilePrintModel::setDive(struct dive *divePtr)
 {
-	dive = divePtr;
+	diveId = divePtr->id;
 	// reset();
 }
 
@@ -1615,8 +1654,10 @@ QVariant ProfilePrintModel::data(const QModelIndex &index, int role) const
 
 	switch (role) {
 	case Qt::DisplayRole: {
+		struct dive *dive = getDiveById(diveId);
+		Q_ASSERT(dive != NULL);
 		struct DiveItem di;
-		di.dive = dive;
+		di.diveId = diveId;
 
 		const QString unknown = tr("unknown");
 

qt-ui/models.h

@@ -101,7 +101,7 @@ public slots:
 	void remove(const QModelIndex& index);
 
 private:
-	struct dive *current;
+	int currentId;
 	int rows;
 };
 
@@ -130,7 +130,7 @@ public slots:
 	void remove(const QModelIndex& index);
 
 private:
-	struct dive *current;
+	int currentId;
 	int rows;
 };
 
@@ -157,7 +157,7 @@ struct DiveItem : public TreeItem {
 		SUIT, CYLINDER, NITROX, SAC, OTU, MAXCNS, LOCATION, COLUMNS };
 
 	virtual QVariant data(int column, int role) const;
-	struct dive* dive;
+	int diveId;
 	virtual bool setData(const QModelIndex& index, const QVariant& value, int role = Qt::EditRole);
 	virtual Qt::ItemFlags flags(const QModelIndex& index) const;
 	QString displayDate() const;
@@ -291,7 +291,7 @@ class ProfilePrintModel : public QAbstractTableModel
 	Q_OBJECT
 
 private:
-	struct dive *dive;
+	int diveId;
 	QString truncateString(char *str, const int maxlen) const;
 
 public:

qt-ui/printlayout.cpp

@@ -391,7 +391,7 @@ void PrintLayout::printTable()
 void PrintLayout::addTablePrintDataRow(TablePrintModel *model, int row, struct dive *dive) const
 {
 	struct DiveItem di;
-	di.dive = dive;
+	di.diveId = dive->id;
 	model->insertRow();
 	model->setData(model->index(row, 0), QString::number(dive->number), Qt::DisplayRole);
 	model->setData(model->index(row, 1), di.displayDate(), Qt::DisplayRole);

qt-ui/profilegraphics.cpp

@@ -52,7 +52,7 @@ extern int evn_used;
 QPoint(viewport()->geometry().width() - toolBarProxy->boundingRect().width(), \
 viewport()->geometry().height() - toolBarProxy->boundingRect().height() )
 
-ProfileGraphicsView::ProfileGraphicsView(QWidget* parent) : QGraphicsView(parent), toolTip(0) , dive(0), diveDC(0), rulerItem(0), toolBarProxy(0)
+ProfileGraphicsView::ProfileGraphicsView(QWidget* parent) : QGraphicsView(parent), toolTip(0) , diveId(0), diveDC(0), rulerItem(0), toolBarProxy(0)
 {
 	printMode = false;
 	isGrayscale = false;
@@ -313,8 +313,8 @@ void ProfileGraphicsView::showEvent(QShowEvent* event)
 	// but the dive was not ploted.
 	// force a replot by modifying the dive
 	// hold by the view, and issuing a plot.
-	if (dive && !scene()->items().count()) {
-		dive = 0;
+	if (diveId && !scene()->items().count()) {
+		diveId = 0;
 		plot(get_dive(selected_dive));
 	}
 	if (toolBarProxy)
@@ -369,14 +369,14 @@ void ProfileGraphicsView::plot(struct dive *d, bool forceRedraw)
 	if (d)
 		dc = select_dc(&d->dc);
 
-	if (!forceRedraw && dive == d && (d && dc == diveDC))
+	if (!forceRedraw && getDiveById(diveId) == d && (d && dc == diveDC))
 		return;
 
 	clear();
-	dive = d;
+	diveId = d ? d->id : 0;
 	diveDC = d ? dc : NULL;
 
-	if (!isVisible() || !dive || !mainWindow()) {
+	if (!isVisible() || !d || !mainWindow()) {
 		return;
 	}
 	setBackgroundBrush(getColor(BACKGROUND));
@@ -415,14 +415,14 @@ void ProfileGraphicsView::plot(struct dive *d, bool forceRedraw)
 	 * Set up limits that are independent of
 	 * the dive computer
 	 */
-	calculate_max_limits(dive, dc, &gc);
+	calculate_max_limits(d, dc, &gc);
 
 	QRectF profile_grid_area = scene()->sceneRect();
 	gc.maxx = (profile_grid_area.width() - 2 * profile_grid_area.x());
 	gc.maxy = (profile_grid_area.height() - 2 * profile_grid_area.y());
 
 	/* This is per-dive-computer */
-	gc.pi = *create_plot_info(dive, dc, &gc, printMode);
+	gc.pi = *create_plot_info(d, dc, &gc, printMode);
 
 	/* Bounding box */
 	QPen pen = defaultPen;
@@ -483,7 +483,7 @@ void ProfileGraphicsView::plot(struct dive *d, bool forceRedraw)
 
 	if(mode == PLAN){
 		timeEditor = new GraphicsTextEditor();
-		timeEditor->setPlainText( dive->duration.seconds ? QString::number(dive->duration.seconds/60) : tr("Set Duration: 10 minutes"));
+		timeEditor->setPlainText(d->duration.seconds ? QString::number(d->duration.seconds/60) : tr("Set Duration: 10 minutes"));
 		timeEditor->setPos(profile_grid_area.width() - timeEditor->boundingRect().width(), timeMarkers->y());
 		timeEditor->document();
 		connect(timeEditor, SIGNAL(editingFinished(QString)), this, SLOT(edit_dive_time(QString)));
@@ -720,6 +720,8 @@ void ProfileGraphicsView::plot_cylinder_pressure_text()
 	int last_time[MAX_CYLINDERS] = { 0, };
 	struct plot_data *entry;
 	struct plot_info *pi = &gc.pi;
+	struct dive *dive = getDiveById(diveId);
+	Q_ASSERT(dive != NULL);
 
 	if (!get_cylinder_pressure_range(&gc))
 		return;
@@ -888,6 +890,8 @@ void ProfileGraphicsView::plot_cylinder_pressure()
 	if (!get_cylinder_pressure_range(&gc))
 		return;
 
+	struct dive *dive = getDiveById(diveId);
+	Q_ASSERT(dive != NULL);
 	QPointF from, to;
 	for (i = 0; i < gc.pi.nr; i++) {
 		int mbar;
@@ -1006,7 +1010,8 @@ void ProfileGraphicsView::plot_one_event(struct event *ev)
 
 	int x = SCALEXGC(ev->time.seconds);
 	int y = SCALEYGC(entry->depth);
-
+	struct dive *dive = getDiveById(diveId);
+	Q_ASSERT(dive != NULL);
 	EventItem *item = new EventItem(ev, 0, isGrayscale);
 	item->setPos(x, y);
 	scene()->addItem(item);

qt-ui/profilegraphics.h

@@ -190,7 +190,7 @@ private:
 	QBrush defaultBrush;
 	ToolTipItem *toolTip;
 	graphics_context gc;
-	struct dive *dive;
+	int diveId;
 	struct divecomputer *diveDC;
 	int zoomLevel;