Send correct surface bounds to xdg_toplevel resources

* compositor.h (struct _RoleFuncs)
(struct _XdgRoleImplementationFuncs): New role functions
`outputs_changed'.
* output.c (NoticeOutputsMaybeChanged): Call surface
outputs_changed hook if it exists.
(XLGetMaxOutputBounds): New function.
* xdg_surface.c (OutputsChanged): New function.
(XLGetXdgSurface): Add new role function.
* xdg_toplevel.c (CurrentWindowGeometry): New function.
(SendStates): Factor out geometry calculation to that function.
(SendOutputBounds): New function.
(Commit, OutputsChanged): Send output bounds whenever
appropriate.
(XLGetXdgToplevel): Add new impl func.

compositor.h

@@ -1083,6 +1083,7 @@ struct _RoleFuncs
   void (*note_child_synced) (Surface *, Role *);
   void (*select_extra_events) (Surface *, Role *, unsigned long);
   void (*note_focus) (Surface *, Role *, FocusMode);
+  void (*outputs_changed) (Surface *, Role *);
 };
 
 struct _Role
@@ -1156,6 +1157,7 @@ extern void *XLAddScaleChangeCallback (void *, void (*) (void *, int));
 extern void XLRemoveScaleChangeCallback (void *);
 extern void XLClearOutputs (Surface *);
 extern void XLOutputSetChangeFunction (void (*) (Time));
+extern void XLGetMaxOutputBounds (int *, int *, int *, int *);
 
 /* Defined in atoms.c.  */
 
@@ -1275,6 +1277,7 @@ struct _XdgRoleImplementationFuncs
   void (*commit_inside_frame) (Role *, XdgRoleImplementation *);
   Bool (*is_window_mapped) (Role *, XdgRoleImplementation *);
   void (*note_focus) (Role *, XdgRoleImplementation *, FocusMode);
+  void (*outputs_changed) (Role *, XdgRoleImplementation *);
 };
 
 struct _XdgRoleImplementation

output.c

@@ -653,7 +653,13 @@ NoticeOutputsMaybeChanged (void)
 
       surface = all_surfaces.next;
       for (; surface != &all_surfaces; surface = surface->next)
-	pixman_region32_clear (&surface->output_region);
+	{
+	  pixman_region32_clear (&surface->output_region);
+
+	  if (surface->role
+	      && surface->role->funcs.outputs_changed)
+	    surface->role->funcs.outputs_changed (surface, surface->role);
+	}
     }
 }
 
@@ -1091,6 +1097,51 @@ XLOutputSetChangeFunction (void (*change_func) (Time))
   change_hook = change_func;
 }
 
+void
+XLGetMaxOutputBounds (int *x_min, int *y_min, int *x_max,
+		      int *y_max)
+{
+  int x1, y1, x2, y2;
+  Output *output;
+  XLList *tem;
+
+  x1 = y1 = INT_MAX;
+  x2 = y2 = INT_MIN;
+
+  if (!all_outputs)
+    {
+      *x_min = 0;
+      *y_min = 0;
+      *x_max = DisplayWidth (compositor.display,
+			     DefaultScreen (compositor.display)) - 1;
+      *y_max = DisplayHeight (compositor.display,
+			      DefaultScreen (compositor.display)) - 1;
+      return;
+    }
+
+  for (tem = all_outputs; tem; tem = tem->next)
+    {
+      output = tem->data;
+
+      if (output->x < x1)
+	x1 = output->x;
+
+      if (output->y < y1)
+	y1 = output->y;
+
+      if (output->x + output->width - 1 > x2)
+	x2 = output->x + output->width - 1;
+
+      if (output->y + output->height - 1 > y2)
+	y2 = output->y + output->height - 1;
+    }
+
+  *x_min = x1;
+  *y_min = y1;
+  *x_max = x2;
+  *y_max = y2;
+}
+
 void
 XLInitRROutputs (void)
 {
@@ -1153,3 +1204,4 @@ XLInitRROutputs (void)
   all_outputs = BuildOutputTree ();
   MakeGlobalsForOutputTree (all_outputs);
 }
+

xdg_surface.c

@@ -1457,6 +1457,17 @@ NoteFocus (Surface *surface, Role *role, FocusMode focus)
 				      focus);
 }
 
+static void
+OutputsChanged (Surface *surface, Role *role)
+{
+  XdgRole *xdg_role;
+
+  xdg_role = XdgRoleFromRole (role);
+
+  if (xdg_role->impl && xdg_role->impl->funcs.outputs_changed)
+    xdg_role->impl->funcs.outputs_changed (role, xdg_role->impl);
+}
+
 void
 XLGetXdgSurface (struct wl_client *client, struct wl_resource *resource,
 		 uint32_t id, struct wl_resource *surface_resource)
@@ -1543,6 +1554,7 @@ XLGetXdgSurface (struct wl_client *client, struct wl_resource *resource,
   role->role.funcs.note_child_synced = NoteChildSynced;
   role->role.funcs.select_extra_events = SelectExtraEvents;
   role->role.funcs.note_focus = NoteFocus;
+  role->role.funcs.outputs_changed = OutputsChanged;
 
   attrs.colormap = compositor.colormap;
   attrs.border_pixel = border_pixel;

xdg_toplevel.c

@@ -572,6 +572,22 @@ WriteStates (XdgToplevel *toplevel)
     AddState (toplevel, XDG_TOPLEVEL_STATE_RESIZING);
 }
 
+static void
+CurrentWindowGeometry (XdgToplevel *toplevel,
+		       int *width, int *height)
+{
+  /* Calculate the current window geometry for sending a configure
+     event.  */
+
+  TruncateScaleToSurface (toplevel->role->surface,
+			  toplevel->width,
+			  toplevel->height,
+			  width, height);
+
+  XLXdgRoleCalcNewWindowSize (toplevel->role, *width,
+			      *height, width, height);
+}
+
 static void
 SendStates (XdgToplevel *toplevel)
 {
@@ -579,16 +595,9 @@ SendStates (XdgToplevel *toplevel)
 
   WriteStates (toplevel);
 
-  /* Adjust the width and height we're sending by the window geometry.
+  /* toplevel->role->surface should not be NULL here.  */
-     toplevel->role->surface should not be NULL here.  */
-
-  TruncateScaleToSurface (toplevel->role->surface,
-			  toplevel->width, toplevel->height,
-			  &width, &height);
-
-  XLXdgRoleCalcNewWindowSize (toplevel->role, width,
-			      height, &width, &height);
 
+  CurrentWindowGeometry (toplevel, &width, &height);
   SendConfigure (toplevel, width, height);
 }
 
@@ -1218,6 +1227,17 @@ AckConfigure (Role *role, XdgRoleImplementation *impl, uint32_t serial)
     toplevel->conf_reply = False;
 }
 
+static void
+SendOutputBounds (XdgToplevel *toplevel)
+{
+  int x_min, y_min, x_max, y_max;
+
+  XLGetMaxOutputBounds (&x_min, &y_min, &x_max, &y_max);
+  xdg_toplevel_send_configure_bounds (toplevel->resource,
+				      x_max - x_min + 1,
+				      y_max - y_min + 1);
+}
+
 static void
 Commit (Role *role, Surface *surface, XdgRoleImplementation *impl)
 {
@@ -1255,6 +1275,14 @@ Commit (Role *role, Surface *surface, XdgRoleImplementation *impl)
 	Unmap (toplevel);
 
       FlushConfigurationTimer (toplevel);
+
+      if (wl_resource_get_version (toplevel->resource) >= 4)
+	/* Send the maximum bounds of the window to the client.  It
+	   isn't possible to predict where the window will be mapped,
+	   so unfortunately the precise output bounds can't be used
+	   here.  */
+	SendOutputBounds (toplevel);
+
       SendConfigure (toplevel, 0, 0);
     }
   else if (!toplevel->conf_reply)
@@ -2181,6 +2209,29 @@ NoteFocus (Role *role, XdgRoleImplementation *impl, FocusMode mode)
     }
 }
 
+static void
+OutputsChanged (Role *role, XdgRoleImplementation *impl)
+{
+  XdgToplevel *toplevel;
+  int width, height;
+
+  toplevel = ToplevelFromRoleImpl (impl);
+
+  /* The list of outputs changed.  Send the new bounds to the
+     client.  */
+  if (toplevel->resource)
+    {
+      if (wl_resource_get_version (toplevel->resource) < 4)
+	/* The client is too old to accept configure_bounds.  */
+	return;
+
+      /* Send the updated bounds to the toplevel.  */
+      SendOutputBounds (toplevel);
+      CurrentWindowGeometry (toplevel, &width, &height);
+      SendConfigure (toplevel, width, height);
+    }
+}
+
 static const struct xdg_toplevel_interface xdg_toplevel_impl =
   {
     .destroy = Destroy,
@@ -2242,6 +2293,7 @@ XLGetXdgToplevel (struct wl_client *client, struct wl_resource *resource,
   toplevel->impl.funcs.post_resize = PostResize;
   toplevel->impl.funcs.commit_inside_frame = CommitInsideFrame;
   toplevel->impl.funcs.is_window_mapped = IsWindowMapped;
+  toplevel->impl.funcs.outputs_changed = OutputsChanged;
 
   if (!XLWmSupportsHint (_NET_WM_STATE_FOCUSED))
     /* If _NET_WM_STATE_FOCUSED is unsupported, fall back to utilizing