Compositor xdg-shell: Warn when clients supply invalid anchor rects

From the protocol: "When the xdg_positioner object is used to position a child
surface, the rectangle may not extend outside the window geometry of the
child's parent surface."

Adds a warning for both v6 and stable when clients do this.

Change-Id: I575a89785f45c080d488be748ec099569b38ea9b
Reviewed-by: Pier Luigi Fiorini <pierluigi.fiorini@liri.io>

src/compositor/extensions/qwaylandxdgshell.cpp

@@ -386,6 +386,7 @@ void QWaylandXdgSurfacePrivate::xdg_surface_get_popup(QtWaylandServer::xdg_surfa
                                "xdg_surface.get_popup without positioner");
         return;
     }
+
     if (!positioner->m_data.isComplete()) {
         QWaylandXdgPositionerData p = positioner->m_data;
         wl_resource_post_error(resource->handle, XDG_WM_BASE_ERROR_INVALID_POSITIONER,
@@ -394,6 +395,17 @@ void QWaylandXdgSurfacePrivate::xdg_surface_get_popup(QtWaylandServer::xdg_surfa
         return;
     }
 
+    QRect anchorBounds(QPoint(0, 0), parent->windowGeometry().size());
+    if (!anchorBounds.contains(positioner->m_data.anchorRect)) {
+        // TODO: this is a protocol error and should ideally be handled like this:
+        //wl_resource_post_error(resource->handle, XDG_WM_BASE_ERROR_INVALID_POSITIONER,
+        //                       "xdg_positioner anchor rect extends beyound its parent's window geometry");
+        //return;
+        // However, our own clients currently do this, so we'll settle for a gentle warning instead.
+        qCWarning(qLcWaylandCompositor) << "Ignoring client protocol error: xdg_positioner anchor"
+                                        << "rect extends beyond its parent's window geometry";
+    }
+
     if (!m_surface->setRole(QWaylandXdgPopup::role(), resource->handle, XDG_WM_BASE_ERROR_ROLE))
         return;
 
@@ -1869,16 +1881,13 @@ QWaylandXdgPopupPrivate::QWaylandXdgPopupPrivate(QWaylandXdgSurface *xdgSurface,
                                                  QWaylandXdgPositioner *positioner, const QWaylandResource &resource)
     : m_xdgSurface(xdgSurface)
     , m_parentXdgSurface(parentXdgSurface)
+    , m_positionerData(positioner->m_data)
 {
+    Q_ASSERT(m_positionerData.isComplete());
     init(resource.resource());
-    m_positionerData = positioner->m_data;
-
-    if (!m_positionerData.isComplete())
-        qWarning() << "Trying to create xdg popup with incomplete positioner";
 
     QWaylandXdgSurfacePrivate::get(m_xdgSurface)->setWindowType(Qt::WindowType::Popup);
 
-    //TODO: positioner rect may not extend parent's window geometry, enforce this?
     //TODO: Need an API for sending a different initial configure
     sendConfigure(QRect(m_positionerData.unconstrainedPosition(), m_positionerData.size));
 }

src/compositor/extensions/qwaylandxdgshellv6.cpp

@@ -391,6 +391,7 @@ void QWaylandXdgSurfaceV6Private::zxdg_surface_v6_get_popup(QtWaylandServer::zxd
                                "zxdg_surface_v6.get_popup without positioner");
         return;
     }
+
     if (!positioner->m_data.isComplete()) {
         QWaylandXdgPositionerV6Data p = positioner->m_data;
         wl_resource_post_error(resource->handle, ZXDG_SHELL_V6_ERROR_INVALID_POSITIONER,
@@ -399,6 +400,17 @@ void QWaylandXdgSurfaceV6Private::zxdg_surface_v6_get_popup(QtWaylandServer::zxd
         return;
     }
 
+    QRect anchorBounds(QPoint(0, 0), parent->windowGeometry().size());
+    if (!anchorBounds.contains(positioner->m_data.anchorRect)) {
+        // TODO: this is a protocol error and should ideally be handled like this:
+        //wl_resource_post_error(resource->handle, ZXDG_SHELL_V6_ERROR_INVALID_POSITIONER,
+        //                       "zxdg_positioner_v6 anchor rect extends beyound its parent's window geometry");
+        //return;
+        // However, our own clients currently do this, so we'll settle for a gentle warning instead.
+        qCWarning(qLcWaylandCompositor) << "Ignoring client protocol error: zxdg_positioner_v6 anchor"
+                                        << "rect extends beyond its parent's window geometry";
+    }
+
     if (!m_surface->setRole(QWaylandXdgPopupV6::role(), resource->handle, ZXDG_SHELL_V6_ERROR_ROLE))
         return;
 
@@ -1800,16 +1812,13 @@ QWaylandXdgPopupV6Private::QWaylandXdgPopupV6Private(QWaylandXdgSurfaceV6 *xdgSu
                                                      QWaylandXdgPositionerV6 *positioner, const QWaylandResource &resource)
     : m_xdgSurface(xdgSurface)
     , m_parentXdgSurface(parentXdgSurface)
+    , m_positionerData(positioner->m_data)
 {
+    Q_ASSERT(m_positionerData.isComplete());
     init(resource.resource());
-    m_positionerData = positioner->m_data;
-
-    if (!m_positionerData.isComplete())
-        qWarning() << "Trying to create xdg popup with incomplete positioner";
 
     QWaylandXdgSurfaceV6Private::get(m_xdgSurface)->setWindowType(Qt::WindowType::Popup);
 
-    //TODO: positioner rect may not extend parent's window geometry, enforce this?
     //TODO: Need an API for sending a different initial configure
     sendConfigure(QRect(m_positionerData.unconstrainedPosition(), m_positionerData.size));
 }