Dive site: pass pointer-to-dive_site via QVariant

There was this ugly pattern of passing pointers-to-dive_site via
a QVariant of void * type. This is of course inherently unsafe.

Pass these pointers using their proper types instead. This makes
it necessary to register them in Qt's meta-type system. Doing so,
fixes a bug: QML couldn't call into updateDiveSiteCoordinates()
because it didn't know the type and thus the coordinates of
the moved flag were not reflected in the divesite-dialog.

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

5 files changed, 11 insertions, 8 deletions

diff --git a/core/divesite.h b/core/divesite.h
index 895412a4b..3ce87128a 100644
--- a/core/divesite.h
+++ b/core/divesite.h
@@ -78,6 +78,9 @@ void merge_dive_sites(struct dive_site *ref, struct dive_site *dive_sites[], int
 }
 QString constructLocationTags(struct taxonomy_data *taxonomy, bool for_maintab);
 
+/* Make pointer-to-dive_site a "Qt metatype" so that we can pass it through QVariants */
+Q_DECLARE_METATYPE(dive_site *);
+
 #endif
 
 #endif // DIVESITE_H
diff --git a/desktop-widgets/locationinformation.cpp b/desktop-widgets/locationinformation.cpp
index 2b57c122c..69ecbc9b2 100644
--- a/desktop-widgets/locationinformation.cpp
+++ b/desktop-widgets/locationinformation.cpp
@@ -82,7 +82,7 @@ void LocationInformationWidget::mergeSelectedDiveSites()
 	std::vector<struct dive_site *> selected_dive_sites;
 	selected_dive_sites.reserve(selection.count());
 	Q_FOREACH (const QModelIndex &idx, selection) {
-		struct dive_site *ds = (struct dive_site *)idx.data(LocationInformationModel::DIVESITE_ROLE).value<void *>();
+		dive_site *ds = idx.data(LocationInformationModel::DIVESITE_ROLE).value<dive_site *>();
 		if (ds)
 			selected_dive_sites.push_back(ds);
 	}
@@ -507,7 +507,7 @@ void DiveLocationLineEdit::itemActivated(const QModelIndex &index)
 	if (index.column() == LocationInformationModel::DIVESITE)
 		idx = index.model()->index(index.row(), LocationInformationModel::NAME);
 
-	dive_site *ds = (dive_site *)index.model()->index(index.row(), LocationInformationModel::DIVESITE).data().value<void *>();
+	dive_site *ds = index.model()->index(index.row(), LocationInformationModel::DIVESITE).data().value<dive_site *>();
 	currType = ds == RECENTLY_ADDED_DIVESITE ? NEW_DIVE_SITE : EXISTING_DIVE_SITE;
 	currDs = ds;
 	setText(idx.data().toString());
diff --git a/desktop-widgets/mapwidget.cpp b/desktop-widgets/mapwidget.cpp
index 9d3735efb..ac90c577d 100644
--- a/desktop-widgets/mapwidget.cpp
+++ b/desktop-widgets/mapwidget.cpp
@@ -67,7 +67,7 @@ void MapWidget::centerOnDiveSite(struct dive_site *ds)
 void MapWidget::centerOnIndex(const QModelIndex& idx)
 {
 	CHECK_IS_READY_RETURN_VOID();
-	struct dive_site *ds = (struct dive_site *)idx.model()->index(idx.row(), LocationInformationModel::DIVESITE).data().value<void *>();
+	dive_site *ds = idx.model()->index(idx.row(), LocationInformationModel::DIVESITE).data().value<dive_site *>();
 	if (!ds || ds == RECENTLY_ADDED_DIVESITE || !dive_site_has_gps_location(ds))
 		centerOnSelectedDiveSite();
 	else
diff --git a/desktop-widgets/modeldelegates.cpp b/desktop-widgets/modeldelegates.cpp
index 7104af33c..f008f4bc2 100644
--- a/desktop-widgets/modeldelegates.cpp
+++ b/desktop-widgets/modeldelegates.cpp
@@ -453,8 +453,8 @@ void LocationFilterDelegate::paint(QPainter *painter, const QStyleOptionViewItem
 	QString diveSiteName = index.data().toString();
 	QString bottomText;
 	QIcon icon = index.data(Qt::DecorationRole).value<QIcon>();
-	struct dive_site *ds = (struct dive_site *)
-		index.model()->data(index.model()->index(index.row(), LocationInformationModel::DIVESITE)).value<void *>();
+	struct dive_site *ds =
+		index.model()->data(index.model()->index(index.row(), LocationInformationModel::DIVESITE)).value<dive_site *>();
 	struct dive_site *currentDiveSite = current_dive ? get_dive_site_for_dive(current_dive) : nullptr;
 	bool currentDiveSiteHasGPS = currentDiveSite && dive_site_has_gps_location(currentDiveSite);
 	//Special case: do not show name, but instead, show
diff --git a/qt-models/divelocationmodel.cpp b/qt-models/divelocationmodel.cpp
index 18be89806..b84604bb5 100644
--- a/qt-models/divelocationmodel.cpp
+++ b/qt-models/divelocationmodel.cpp
@@ -41,7 +41,7 @@ QVariant LocationInformationModel::getDiveSiteData(const struct dive_site *ds, i
 	case Qt::EditRole:
 	case Qt::DisplayRole :
 		switch(column) {
-		case DIVESITE: return QVariant::fromValue<void*>((void *)ds); // Not nice: casting away const
+		case DIVESITE: return QVariant::fromValue<dive_site *>((dive_site *)ds); // Not nice: casting away const
 		case NAME: return ds->name;
 		case LATITUDE: return ds->location.lat.udeg;
 		case LONGITUDE: return ds->location.lon.udeg;
@@ -60,7 +60,7 @@ QVariant LocationInformationModel::getDiveSiteData(const struct dive_site *ds, i
 			return QVariant();
 	}
 	case DIVESITE_ROLE:
-		return QVariant::fromValue<void *>((void *)ds); // Not nice: casting away const
+		return QVariant::fromValue<dive_site *>((dive_site *)ds); // Not nice: casting away const
 	}
 	return QVariant();
 }
@@ -119,7 +119,7 @@ GeoReferencingOptionsModel::GeoReferencingOptionsModel(QObject *parent) : QStrin
 
 bool GPSLocationInformationModel::filterAcceptsRow(int sourceRow, const QModelIndex &parent) const
 {
-	struct dive_site *ds = (struct dive_site *)sourceModel()->index(sourceRow, LocationInformationModel::DIVESITE, parent).data().value<void *>();
+	struct dive_site *ds = sourceModel()->index(sourceRow, LocationInformationModel::DIVESITE, parent).data().value<dive_site *>();
 	if (ds == ignoreDs || ds == RECENTLY_ADDED_DIVESITE)
 		return false;