[Qt] Sanitize QSize → mbgl::Size conversion

platform/qt/src/qmapboxgl.cpp

@@ -79,6 +79,13 @@ auto fromQStringList(const QStringList &list)
     return strings;
 }
 
+mbgl::Size sanitizedSize(const QSize& size) {
+    return mbgl::Size {
+        size.width() <= 0 ? 0 : static_cast<uint32_t>(size.width()),
+        size.height() <= 0 ? 0 : static_cast<uint32_t>(size.height())
+    };
+};
+
 std::unique_ptr<const mbgl::SpriteImage> toSpriteImage(const QImage &sprite) {
     const QImage swapped = sprite
         .rgbSwapped()
@@ -433,6 +440,8 @@ void QMapboxGLSettings::setApiBaseUrl(const QString& url)
 QMapboxGL::QMapboxGL(QObject *parent, const QMapboxGLSettings &settings, const QSize& size, qreal pixelRatio)
     : QObject(parent)
 {
+    assert(!size.isEmpty());
+
     // Multiple QMapboxGL running on the same thread
     // will share the same mbgl::util::RunLoop
     if (!loop.hasLocalData()) {
@@ -1079,8 +1088,7 @@ void QMapboxGL::resize(const QSize& size, const QSize& framebufferSize)
     d_ptr->size = size;
     d_ptr->fbSize = framebufferSize;
 
-    d_ptr->mapObj->setSize(
-        { static_cast<uint32_t>(size.width()), static_cast<uint32_t>(size.height()) });
+    d_ptr->mapObj->setSize(sanitizedSize(size));
 }
 
 /*!
@@ -1547,14 +1555,15 @@ QMapboxGLPrivate::QMapboxGLPrivate(QMapboxGL *q, const QMapboxGLSettings &settin
         settings.assetPath().toStdString(),
         settings.cacheDatabaseMaximumSize()))
     , threadPool(mbgl::sharedThreadPool())
-    , mapObj(std::make_unique<mbgl::Map>(
-        *this, mbgl::Size{ static_cast<uint32_t>(size.width()), static_cast<uint32_t>(size.height()) },
-        pixelRatio, *fileSourceObj, *threadPool,
-        mbgl::MapMode::Continuous,
-        static_cast<mbgl::GLContextMode>(settings.contextMode()),
-        static_cast<mbgl::ConstrainMode>(settings.constrainMode()),
-        static_cast<mbgl::ViewportMode>(settings.viewportMode())))
 {
+    mapObj = std::make_unique<mbgl::Map>(
+            *this, sanitizedSize(size),
+            pixelRatio, *fileSourceObj, *threadPool,
+            mbgl::MapMode::Continuous,
+            static_cast<mbgl::GLContextMode>(settings.contextMode()),
+            static_cast<mbgl::ConstrainMode>(settings.constrainMode()),
+            static_cast<mbgl::ViewportMode>(settings.viewportMode()));
+
     qRegisterMetaType<QMapboxGL::MapChange>("QMapboxGL::MapChange");
 
     fileSourceObj->setAccessToken(settings.accessToken().toStdString());
@@ -1570,7 +1579,7 @@ QMapboxGLPrivate::~QMapboxGLPrivate()
 }
 
 mbgl::Size QMapboxGLPrivate::framebufferSize() const {
-    return { static_cast<uint32_t>(fbSize.width()), static_cast<uint32_t>(fbSize.height()) };
+    return sanitizedSize(fbSize);
 }
 
 void QMapboxGLPrivate::updateAssumedState() {