Introduce SurfaceRole name property

This can be useful for protocol error messages.

src/server/inputmethod_v1_interface.cpp

@@ -279,7 +279,7 @@ class InputPanelSurfaceV1InterfacePrivate : public QtWaylandServer::zwp_input_pa
 public:
     InputPanelSurfaceV1InterfacePrivate(SurfaceInterface *surface, quint32 id, InputPanelSurfaceV1Interface *q)
         : zwp_input_panel_surface_v1()
-        , SurfaceRole(surface)
+        , SurfaceRole(surface, QByteArrayLiteral("input_panel_surface_v1"))
         , q(q)
     {
         Q_UNUSED(id)
@@ -329,7 +329,9 @@ public:
 
         SurfaceRole *surfaceRole = SurfaceRole::get(surface);
         if (surfaceRole) {
-            wl_resource_post_error(resource->handle, 0, "the surface already has a role assigned");
+            wl_resource_post_error(resource->handle, 0,
+                                   "the surface already has a role assigned %s",
+                                   surfaceRole->name().constData());
             return;
         }
 

src/server/layershell_v1_interface.cpp

@@ -110,7 +110,8 @@ void LayerShellV1InterfacePrivate::zwlr_layer_shell_v1_get_layer_surface(Resourc
     SurfaceRole *surfaceRole = SurfaceRole::get(surface);
     if (surfaceRole) {
         wl_resource_post_error(resource->handle, error_role,
-                               "the wl_surface already has a role assigned");
+                               "the wl_surface already has a role assigned %s",
+                               surfaceRole->name().constData());
         return;
     }
 
@@ -150,7 +151,7 @@ Display *LayerShellV1Interface::display() const
 
 LayerSurfaceV1InterfacePrivate::LayerSurfaceV1InterfacePrivate(LayerSurfaceV1Interface *q,
                                                                SurfaceInterface *surface)
-    : SurfaceRole(surface)
+    : SurfaceRole(surface, QByteArrayLiteral("layer_surface_v1"))
     , q(q)
     , surface(surface)
 {

src/server/surfacerole.cpp

@@ -11,8 +11,9 @@
 namespace KWaylandServer
 {
 
-SurfaceRole::SurfaceRole(SurfaceInterface *surface)
+SurfaceRole::SurfaceRole(SurfaceInterface *surface, const QByteArray &name)
     : m_surface(surface)
+    , m_name(name)
 {
     SurfaceInterfacePrivate *surfacePrivate = SurfaceInterfacePrivate::get(surface);
     surfacePrivate->role = this;
@@ -27,6 +28,11 @@ SurfaceRole::~SurfaceRole()
     }
 }
 
+QByteArray SurfaceRole::name() const
+{
+    return m_name;
+}
+
 SurfaceRole *SurfaceRole::get(SurfaceInterface *surface)
 {
     if (surface) {

src/server/surfacerole_p.h

@@ -7,6 +7,7 @@
 #ifndef KWAYLAND_SERVER_SURFACEROLE_P_H
 #define KWAYLAND_SERVER_SURFACEROLE_P_H
 
+#include <QByteArray>
 #include <QPointer>
 
 namespace KWaylandServer
@@ -17,9 +18,10 @@ class SurfaceInterface;
 class SurfaceRole
 {
 public:
-    explicit SurfaceRole(SurfaceInterface *surface);
+    SurfaceRole(SurfaceInterface *surface, const QByteArray &name);
     virtual ~SurfaceRole();
 
+    QByteArray name() const;
     const QPointer<SurfaceInterface> &surface() const
     {
         return m_surface;
@@ -31,6 +33,7 @@ public:
 
 private:
     QPointer<SurfaceInterface> m_surface;
+    QByteArray m_name;
 
     Q_DISABLE_COPY(SurfaceRole)
 };

src/server/xdgshell_interface.cpp

@@ -186,9 +186,11 @@ void XdgSurfaceInterfacePrivate::xdg_surface_destroy(Resource *resource)
 
 void XdgSurfaceInterfacePrivate::xdg_surface_get_toplevel(Resource *resource, uint32_t id)
 {
-    if (SurfaceRole::get(surface)) {
+    const SurfaceRole *surfaceRole = SurfaceRole::get(surface);
+    if (surfaceRole) {
         wl_resource_post_error(resource->handle, error_already_constructed,
-                               "xdg_surface has already been constructured");
+                               "the surface already has a role assigned %s",
+                               surfaceRole->name().constData());
         return;
     }
 
@@ -203,9 +205,11 @@ void XdgSurfaceInterfacePrivate::xdg_surface_get_popup(Resource *resource, uint3
                                                        ::wl_resource *parentResource,
                                                        ::wl_resource *positionerResource)
 {
-    if (SurfaceRole::get(surface)) {
+    const SurfaceRole *surfaceRole = SurfaceRole::get(surface);
+    if (surfaceRole) {
         wl_resource_post_error(resource->handle, error_already_constructed,
-                               "xdg_surface has already been constructured");
+                               "the surface already has a role assigned %s",
+                               surfaceRole->name().constData());
         return;
     }
 
@@ -305,7 +309,7 @@ XdgSurfaceInterface *XdgSurfaceInterface::get(::wl_resource *resource)
 
 XdgToplevelInterfacePrivate::XdgToplevelInterfacePrivate(XdgToplevelInterface *toplevel,
                                                          XdgSurfaceInterface *surface)
-    : SurfaceRole(surface->surface())
+    : SurfaceRole(surface->surface(), QByteArrayLiteral("xdg_toplevel"))
     , q(toplevel)
     , xdgSurface(surface)
 {
@@ -637,7 +641,7 @@ XdgPopupInterfacePrivate *XdgPopupInterfacePrivate::get(XdgPopupInterface *popup
 
 XdgPopupInterfacePrivate::XdgPopupInterfacePrivate(XdgPopupInterface *popup,
                                                    XdgSurfaceInterface *surface)
-    : SurfaceRole(surface->surface())
+    : SurfaceRole(surface->surface(), QByteArrayLiteral("xdg_popup"))
     , q(popup)
     , xdgSurface(surface)
 {