Use QPointer to avoid dangling QDeclarativeGeoRoute in NavigatorPrivate

QDeclarativeNavigator::setRoute takes a QDeclarativeGeoRoute.
This type is not COW, and could be destroyed by the user or the route
model.

This patch stores it inside a QPointer.
It also stores the contained QGeoRoute, that is what the navigation
engines are supposed to use to perform navigation, and is COW.

Task-number: QTBUG-68536
Change-Id: I73fb79faeb3ac9efefcbd778ee106d29fbf26658
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Alex Blasche <alexander.blasche@qt.io>

4 files changed, 45 insertions, 8 deletions

diff --git a/src/location/labs/labs.pri b/src/location/labs/labs.pri
index 2da5e90d..79a22700 100644
--- a/src/location/labs/labs.pri
+++ b/src/location/labs/labs.pri
@@ -1,3 +1,4 @@
+QT += positioningquick-private
 INCLUDEPATH += labs
 
 PRIVATE_HEADERS += $$files($$PWD/*.h) $$files($$PWD/qsg/*.h)
diff --git a/src/location/labs/qdeclarativenavigator.cpp b/src/location/labs/qdeclarativenavigator.cpp
index bcb74c90..5fe36bb8 100644
--- a/src/location/labs/qdeclarativenavigator.cpp
+++ b/src/location/labs/qdeclarativenavigator.cpp
@@ -37,6 +37,7 @@
 #include <QtLocation/private/qdeclarativegeoroute_p.h>
 #include <QtLocation/private/qdeclarativegeoroutemodel_p.h>
 #include <QtLocation/private/qdeclarativegeoroutesegment_p.h>
+#include <QtPositioningQuick/private/qdeclarativepositionsource_p.h>
 #include <QtQml/qqmlinfo.h>
 
 QT_BEGIN_NAMESPACE
@@ -165,6 +166,12 @@ QDeclarativeNavigatorPrivate::QDeclarativeNavigatorPrivate(QParameterizableObjec
 {
 }
 
+void QDeclarativeNavigatorPrivate::updateReadyState()
+{
+    qobject_cast<QDeclarativeNavigator *>(q)->updateReadyState();
+}
+
+
 
 QDeclarativeNavigator::QDeclarativeNavigator(QObject *parent)
     : QParameterizableObject(parent), d_ptr(new QDeclarativeNavigatorPrivate(this))
@@ -195,10 +202,16 @@ QDeclarativeGeoServiceProvider *QDeclarativeNavigator::plugin() const
 
 void QDeclarativeNavigator::setMap(QDeclarativeGeoMap *map)
 {
-    if (d_ptr->m_map) // set once prop
+    if (d_ptr->m_map || !map) // set once prop
         return;
 
     d_ptr->m_map = map;
+    QDeclarativeNavigatorPrivate *dptr = d_ptr.data();
+    connect(map, &QObject::destroyed,
+            [this, dptr]() {
+                this->mapChanged();
+                dptr->updateReadyState();
+            });
     emit mapChanged();
     updateReadyState();
 }
@@ -219,6 +232,15 @@ void QDeclarativeNavigator::setRoute(QDeclarativeGeoRoute *route)
         setActive(false); // Stop current session
 
     d_ptr->m_route = route;
+    d_ptr->m_geoRoute = route ? route->route() : QGeoRoute();
+    if (route) {
+        connect(route, &QObject::destroyed,
+                [this]() {
+                    // Do not stop navigation if route disappears. d_ptr->m_geoRoute will still be valid.
+                    // Engines can stop navigation if desired.
+                    this->routeChanged();
+                });
+    }
     emit routeChanged();
     updateReadyState();
 }
@@ -230,10 +252,17 @@ QDeclarativeGeoRoute *QDeclarativeNavigator::route() const
 
 void QDeclarativeNavigator::setPositionSource(QDeclarativePositionSource *positionSource)
 {
-    if (d_ptr->m_positionSource) // set once prop
+    if (d_ptr->m_positionSource || !positionSource) // set once prop
         return;
 
     d_ptr->m_positionSource = positionSource;
+    QDeclarativeNavigatorPrivate *dptr = d_ptr.data();
+    QObject::connect(positionSource, &QObject::destroyed,
+            [this, dptr]() {
+                this->positionSourceChanged();
+                dptr->updateReadyState();
+            }
+    );
     emit positionSourceChanged();
     updateReadyState();
 }
@@ -258,8 +287,8 @@ bool QDeclarativeNavigator::navigatorReady() const
 QDeclarativeGeoRoute *QDeclarativeNavigator::currentRoute() const
 {
     if (!d_ptr->m_ready || !d_ptr->m_navigationManager->active())
-        return d_ptr->m_route;
-    return d_ptr->m_currentRoute;
+        return d_ptr->m_route.data();
+    return d_ptr->m_currentRoute.data();
 }
 
 int QDeclarativeNavigator::currentSegment() const
diff --git a/src/location/labs/qdeclarativenavigator_p.h b/src/location/labs/qdeclarativenavigator_p.h
index 3c9a4653..0373bf57 100644
--- a/src/location/labs/qdeclarativenavigator_p.h
+++ b/src/location/labs/qdeclarativenavigator_p.h
@@ -136,6 +136,8 @@ private slots:
 
 private:
     QScopedPointer<QDeclarativeNavigatorPrivate> d_ptr;
+
+    friend class QDeclarativeNavigatorPrivate;
 };
 
 QT_END_NAMESPACE
diff --git a/src/location/labs/qdeclarativenavigator_p_p.h b/src/location/labs/qdeclarativenavigator_p_p.h
index 0485ee69..c4198714 100644
--- a/src/location/labs/qdeclarativenavigator_p_p.h
+++ b/src/location/labs/qdeclarativenavigator_p_p.h
@@ -50,6 +50,8 @@
 
 #include <QtCore/qlist.h>
 #include <QtLocation/private/qlocationglobal_p.h>
+#include <QtCore/qpointer.h>
+#include <QtLocation/qgeoroute.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -67,13 +69,16 @@ class Q_LOCATION_PRIVATE_EXPORT QDeclarativeNavigatorPrivate
 public:
     QDeclarativeNavigatorPrivate(QParameterizableObject *q_);
 
+    void updateReadyState();
+
     QParameterizableObject *q = nullptr;
     QNavigationManager *m_navigationManager = nullptr;
     QDeclarativeGeoServiceProvider *m_plugin = nullptr;
-    QDeclarativeGeoMap *m_map = nullptr;
-    QDeclarativeGeoRoute *m_route = nullptr;
-    QDeclarativePositionSource *m_positionSource = nullptr;
-    QDeclarativeGeoRoute *m_currentRoute = nullptr;
+    QPointer<QDeclarativeGeoMap> m_map;
+    QPointer<QDeclarativeGeoRoute> m_route;
+    QGeoRoute m_geoRoute;
+    QPointer<QDeclarativePositionSource> m_positionSource;
+    QPointer<QDeclarativeGeoRoute> m_currentRoute;
     QList<QGeoMapParameter *> m_parameters;
     int m_currentSegment = 0;
     bool m_active = false;