core,wayland,compositor,x11: Migrate to MetaWindowDrag

Flip the switch in using MetaWindowDrag, leaving display grab
ops and a bunch other code unused. Some places checked the grab op
and/or window in complex ways, others just checked for grab existence
and should now look for clutter ones, and others already were already
doing this in addition.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2683>

doc/code-overview.txt

@@ -132,6 +132,7 @@ Getting started -- where to look
       constraints.c
       update_move
       update_resize
+      meta-window-drag.c
       meta_window_handle_mouse_grab_op_event
       _NET_MOVERESIZE_WINDOW
       _NET_WM_STRUT

src/compositor/meta-window-actor-x11.c

@@ -1242,6 +1242,7 @@ meta_window_actor_x11_after_paint (MetaWindowActor  *actor,
 {
   MetaWindowActorX11 *actor_x11 = META_WINDOW_ACTOR_X11 (actor);
   MetaSyncCounter *sync_counter;
+  MetaWindowDrag *window_drag;
   MetaWindow *window;
 
   actor_x11->repaint_scheduled = FALSE;
@@ -1274,8 +1275,11 @@ meta_window_actor_x11_after_paint (MetaWindowActor  *actor,
       meta_window_x11_set_thaw_after_paint (window, FALSE);
     }
 
-  if (window == window->display->grab_window &&
+  window_drag = meta_compositor_get_current_window_drag (window->display->compositor);
-      meta_grab_op_is_resizing (window->display->grab_op))
+
+  if (window_drag &&
+      window == meta_window_drag_get_window (window_drag) &&
+      meta_grab_op_is_resizing (meta_window_drag_get_grab_op (window_drag)))
     {
       /* This means we are ready for another configure;
        * no pointer round trip here, to keep in sync */

src/compositor/meta-window-drag.c

@@ -608,6 +608,9 @@ process_keyboard_move_grab (MetaWindowDrag  *window_drag,
                   "Computed new window location %d,%d due to keypress",
                   x, y);
 
+      window_drag->last_edge_resistance_flags =
+        flags & ~META_EDGE_RESISTANCE_KEYBOARD_OP;
+
       meta_window_edge_resistance_for_move (window,
                                             &x,
                                             &y,
@@ -959,6 +962,9 @@ process_keyboard_resize_grab (MetaWindowDrag  *window_drag,
                   "%dx%d, gravity %s",
                   width, height, meta_gravity_to_string (gravity));
 
+      window_drag->last_edge_resistance_flags =
+        flags & ~META_EDGE_RESISTANCE_KEYBOARD_OP;
+
       /* Do any edge resistance/snapping */
       meta_window_edge_resistance_for_resize (window,
                                               &width,
@@ -1257,6 +1263,9 @@ update_move (MetaWindowDrag          *window_drag,
   if (window->maximized_vertically)
     new_y = old.y;
 
+  window_drag->last_edge_resistance_flags =
+    flags & ~META_EDGE_RESISTANCE_KEYBOARD_OP;
+
   /* Do any edge resistance/snapping */
   meta_window_edge_resistance_for_move (window,
                                         &new_x,
@@ -1410,6 +1419,9 @@ update_resize (MetaWindowDrag          *window_drag,
   gravity = meta_resize_gravity_from_grab_op (window_drag->grab_op);
   g_assert (gravity >= 0);
 
+  window_drag->last_edge_resistance_flags =
+    flags & ~META_EDGE_RESISTANCE_KEYBOARD_OP;
+
   /* Do any edge resistance/snapping */
   meta_window_edge_resistance_for_resize (window,
                                           &new_rect.width,

src/core/constraints.c

@@ -31,6 +31,7 @@
 #include "backends/meta-backend-private.h"
 #include "backends/meta-logical-monitor.h"
 #include "backends/meta-monitor-manager-private.h"
+#include "compositor/compositor-private.h"
 #include "core/boxes-private.h"
 #include "core/meta-workspace-manager-private.h"
 #include "core/place.h"
@@ -1761,16 +1762,21 @@ constrain_titlebar_visible (MetaWindow         *window,
   int bottom_amount;
   int horiz_amount_offscreen, vert_amount_offscreen;
   int horiz_amount_onscreen,  vert_amount_onscreen;
+  MetaWindowDrag *window_drag;
 
   if (priority > PRIORITY_TITLEBAR_VISIBLE)
     return TRUE;
 
+  window_drag = meta_compositor_get_current_window_drag (window->display->compositor);
+
   /* Allow the titlebar beyond the top of the screen only if the user wasn't
    * clicking on the frame to start the move.
    */
   unconstrained_user_action =
     info->is_user_action &&
-    (window->display->grab_op & META_GRAB_OP_WINDOW_FLAG_UNCONSTRAINED) != 0;
+    window_drag &&
+    (meta_window_drag_get_grab_op (window_drag) &
+     META_GRAB_OP_WINDOW_FLAG_UNCONSTRAINED) != 0;
 
   /* Exit early if we know the constraint won't apply--note that this constraint
    * is only meant for normal windows (e.g. we don't want docks to be shoved

src/core/delete.c

@@ -69,7 +69,7 @@ meta_window_show_close_dialog (MetaWindow *window)
   meta_close_dialog_show (window->close_dialog);
 
   if (window->display &&
-      window->display->grab_op == META_GRAB_OP_NONE &&
+      !meta_compositor_get_current_window_drag (window->display->compositor) &&
       window == window->display->focus_window)
     meta_close_dialog_focus (window->close_dialog);
 }

src/core/display.c

@@ -1259,10 +1259,7 @@ meta_display_windows_are_interactable (MetaDisplay *display)
   if (clutter_stage_get_grab_actor (CLUTTER_STAGE (stage)))
     return FALSE;
 
-  if (display->grab_op == META_GRAB_OP_NONE)
+  return TRUE;
-    return TRUE;
-
-  return FALSE;
 }
 
 /**
@@ -1998,7 +1995,7 @@ meta_display_end_grab_op (MetaDisplay *display,
 gboolean
 meta_display_is_grabbed (MetaDisplay *display)
 {
-  return display->grab_op != META_GRAB_OP_NONE;
+  return meta_compositor_get_current_window_drag (display->compositor) != NULL;
 }
 
 void
@@ -3151,11 +3148,16 @@ static gboolean
 meta_display_update_tile_preview_timeout (gpointer data)
 {
   MetaDisplay *display = data;
-  MetaWindow *window = display->grab_window;
+  MetaWindowDrag *window_drag;
+  MetaWindow *window = NULL;
   gboolean needs_preview = FALSE;
 
   display->tile_preview_timeout_id = 0;
 
+  window_drag = meta_compositor_get_current_window_drag (display->compositor);
+  if (window_drag)
+    window = meta_window_drag_get_window (window_drag);
+
   if (window)
     {
       switch (display->preview_tile_mode)

src/core/edge-resistance.c

@@ -23,6 +23,7 @@
 
 #include "core/edge-resistance.h"
 
+#include "compositor/compositor-private.h"
 #include "core/boxes-private.h"
 #include "core/display-private.h"
 #include "core/meta-workspace-manager-private.h"
@@ -33,7 +34,8 @@
  */
 #define WINDOW_EDGES_RELEVANT(window, display) \
   meta_window_should_be_showing (window) &&    \
-  window         != display->grab_window &&    \
+  (!meta_compositor_get_current_window_drag (display->compositor) || \
+   window != meta_window_drag_get_window (meta_compositor_get_current_window_drag (display->compositor))) && \
   window->type   != META_WINDOW_DESKTOP &&     \
   window->type   != META_WINDOW_MENU    &&     \
   window->type   != META_WINDOW_SPLASHSCREEN
@@ -887,11 +889,14 @@ compute_resistance_and_snapping_edges (MetaDisplay *display)
    */
   GSList *rem_windows, *rem_win_stacking;
   MetaWorkspaceManager *workspace_manager = display->workspace_manager;
+  MetaWindowDrag *window_drag;
 
-  g_assert (display->grab_window != NULL);
+  window_drag = meta_compositor_get_current_window_drag (display->compositor);
+
+  g_assert (window_drag != NULL);
   meta_topic (META_DEBUG_WINDOW_OPS,
               "Computing edges to resist-movement or snap-to for %s.",
-              display->grab_window->desc);
+              meta_window_drag_get_window (window_drag)->desc);
 
   /*
    * 1st: Get the list of relevant windows, from bottom to top

src/core/events.c

@@ -43,8 +43,6 @@
 #include "wayland/meta-wayland-private.h"
 #endif
 
-#define META_GRAB_OP_GET_BASE_TYPE(op) (op & 0x00FF)
-
 #define IS_GESTURE_EVENT(e) ((e)->type == CLUTTER_TOUCHPAD_SWIPE || \
                              (e)->type == CLUTTER_TOUCHPAD_PINCH || \
                              (e)->type == CLUTTER_TOUCHPAD_HOLD || \
@@ -87,34 +85,23 @@ get_window_for_event (MetaDisplay        *display,
                       const ClutterEvent *event,
                       ClutterActor       *event_actor)
 {
-  switch (META_GRAB_OP_GET_BASE_TYPE (display->grab_op))
+  MetaWindowActor *window_actor;
+
+  if (stage_has_grab (display))
+    return NULL;
+
+  /* Always use the key focused window for key events. */
+  if (IS_KEY_EVENT (event))
     {
-    case META_GRAB_OP_NONE:
+      return stage_has_key_focus (display) ? display->focus_window
-      {
+        : NULL;
-        MetaWindowActor *window_actor;
-
-        if (stage_has_grab (display))
-          return NULL;
-
-        /* Always use the key focused window for key events. */
-        if (IS_KEY_EVENT (event))
-          {
-            return stage_has_key_focus (display) ? display->focus_window
-                                                 : NULL;
-          }
-
-        window_actor = meta_window_actor_from_actor (event_actor);
-        if (window_actor)
-          return meta_window_actor_get_meta_window (window_actor);
-        else
-          return NULL;
-      }
-    case META_GRAB_OP_WINDOW_BASE:
-      return display->grab_window;
-    default:
-      g_assert_not_reached ();
-      return NULL;
     }
+
+  window_actor = meta_window_actor_from_actor (event_actor);
+  if (window_actor)
+    return meta_window_actor_get_meta_window (window_actor);
+  else
+    return NULL;
 }
 
 static void
@@ -224,6 +211,7 @@ meta_display_handle_event (MetaDisplay        *display,
 {
   MetaContext *context = meta_display_get_context (display);
   MetaBackend *backend = meta_context_get_backend (context);
+  MetaCompositor *compositor = meta_display_get_compositor (display);
   ClutterInputDevice *device;
   MetaWindow *window = NULL;
   gboolean bypass_clutter = FALSE;
@@ -243,8 +231,6 @@ meta_display_handle_event (MetaDisplay        *display,
 
   if (display->grabbed_in_clutter != has_grab)
     {
-      MetaCompositor *compositor = meta_display_get_compositor (display);
-
 #ifdef HAVE_WAYLAND
       if (wayland_compositor)
         meta_display_sync_wayland_input_focus (display);
@@ -389,23 +375,14 @@ meta_display_handle_event (MetaDisplay        *display,
       goto out;
     }
 
-  if (display->grab_op != META_GRAB_OP_NONE)
-    {
-      if (meta_window_handle_mouse_grab_op_event (window, event))
-        {
-          bypass_clutter = TRUE;
-          bypass_wayland = TRUE;
-          goto out;
-        }
-    }
-
   /* For key events, it's important to enforce single-handling, or
    * we can get into a confused state. So if a keybinding is
    * handled (because it's one of our hot-keys, or because we are
    * in a keyboard-grabbed mode like moving a window, we don't
    * want to pass the key event to the compositor or Wayland at all.
    */
-  if (meta_keybindings_process_event (display, window, event))
+  if (!meta_compositor_get_current_window_drag (compositor) &&
+      meta_keybindings_process_event (display, window, event))
     {
       bypass_clutter = TRUE;
       bypass_wayland = TRUE;
@@ -415,7 +392,7 @@ meta_display_handle_event (MetaDisplay        *display,
   /* Do not pass keyboard events to Wayland if key focus is not on the
    * stage in normal mode (e.g. during keynav in the panel)
    */
-  if (display->grab_op == META_GRAB_OP_NONE)
+  if (!has_grab)
     {
       if (IS_KEY_EVENT (event) && !stage_has_key_focus (display))
         {
@@ -484,7 +461,7 @@ meta_display_handle_event (MetaDisplay        *display,
        * event, and if it doesn't, replay the event to release our
        * own sync grab. */
 
-      if (display->grab_op != META_GRAB_OP_NONE)
+      if (meta_compositor_get_current_window_drag (compositor))
         {
           bypass_clutter = TRUE;
           bypass_wayland = TRUE;

src/core/window.c

@@ -1531,11 +1531,6 @@ meta_window_unmanage (MetaWindow  *window,
       invalidate_work_areas (window);
     }
 
-  if (window->display->grab_window == window)
-    meta_display_end_grab_op (window->display, timestamp);
-
-  g_assert (window->display->grab_window != window);
-
   if (window->maximized_horizontally || window->maximized_vertically)
     unmaximize_window_before_freeing (window);
 
@@ -2832,6 +2827,7 @@ meta_window_update_tile_fraction (MetaWindow *window,
 {
   MetaWindow *tile_match = window->tile_match;
   MetaRectangle work_area;
+  MetaWindowDrag *window_drag;
 
   if (!META_WINDOW_TILED_SIDE_BY_SIDE (window))
     return;
@@ -2841,7 +2837,12 @@ meta_window_update_tile_fraction (MetaWindow *window,
                                          &work_area);
   window->tile_hfraction = (double)new_w / work_area.width;
 
-  if (tile_match && window->display->grab_window == window)
+  window_drag =
+    meta_compositor_get_current_window_drag (window->display->compositor);
+
+  if (tile_match &&
+      window_drag &&
+      meta_window_drag_get_window (window_drag) == window)
     meta_window_tile (tile_match, tile_match->tile_mode);
 }
 
@@ -2925,6 +2926,7 @@ meta_window_tile (MetaWindow   *window,
                   MetaTileMode  tile_mode)
 {
   MetaMaximizeFlags directions;
+  MetaWindowDrag *window_drag;
 
   g_return_if_fail (META_IS_WINDOW (window));
 
@@ -2950,7 +2952,12 @@ meta_window_tile (MetaWindow   *window,
   meta_window_maximize_internal (window, directions, NULL);
   meta_display_update_tile_preview (window->display, FALSE);
 
-  if (!window->tile_match || window->tile_match != window->display->grab_window)
+  window_drag =
+    meta_compositor_get_current_window_drag (window->display->compositor);
+
+  if (!window->tile_match ||
+      !window_drag ||
+      window->tile_match != meta_window_drag_get_window (window_drag))
     {
       MetaRectangle old_frame_rect, old_buffer_rect;
 
@@ -4175,10 +4182,16 @@ meta_window_resize_frame_with_gravity (MetaWindow *window,
 
   if (user_op)
     {
+      MetaWindowDrag *window_drag;
+
+      window_drag =
+        meta_compositor_get_current_window_drag (window->display->compositor);
+
       /* When resizing in-tandem with a tile match, we need to respect
        * its minimum width
        */
-      if (window->display->grab_window == window)
+      if (window_drag &&
+          meta_window_drag_get_window (window_drag) == window)
         adjust_size_for_tile_match (window, &w, &h);
       meta_window_update_tile_fraction (window, w, h);
     }
@@ -4557,6 +4570,8 @@ meta_window_focus (MetaWindow  *window,
   MetaWindow *modal_transient;
   MetaBackend *backend;
   ClutterStage *stage;
+  MetaWindowDrag *window_drag;
+  MetaWindow *grab_window = NULL;
 
   g_return_if_fail (!window->override_redirect);
 
@@ -4575,14 +4590,18 @@ meta_window_focus (MetaWindow  *window,
       return;
     }
 
-  if (window->display->grab_window &&
+  window_drag =
-      window->display->grab_window != window &&
+    meta_compositor_get_current_window_drag (window->display->compositor);
-      window->display->grab_window->all_keys_grabbed &&
+  if (window_drag)
-      !window->display->grab_window->unmanaging)
+    grab_window = meta_window_drag_get_window (window_drag);
+
+  if (grab_window &&
+      grab_window != window &&
+      !grab_window->unmanaging)
     {
       meta_topic (META_DEBUG_FOCUS,
                   "Current focus window %s has global keygrab, not focusing window %s after all",
-                  window->display->grab_window->desc, window->desc);
+                  grab_window->desc, window->desc);
       return;
     }
 
@@ -6735,31 +6754,9 @@ meta_window_begin_grab_op (MetaWindow *window,
                            MetaGrabOp  op,
                            guint32     timestamp)
 {
-  int x, y;
+  return meta_compositor_drag_window (window->display->compositor,
-
+                                      window, op,
-  if ((op & META_GRAB_OP_KEYBOARD_MOVING) == META_GRAB_OP_KEYBOARD_MOVING)
+                                      timestamp);
-    {
-      warp_grab_pointer (window, op, &x, &y);
-    }
-  else
-    {
-      MetaBackend *backend = backend_from_window (window);
-      ClutterBackend *clutter_backend = meta_backend_get_clutter_backend (backend);
-      ClutterSeat *seat = clutter_backend_get_default_seat (clutter_backend);
-      ClutterInputDevice *device;
-      graphene_point_t pos;
-
-      device = clutter_seat_get_pointer (seat);
-      clutter_seat_query_state (seat, device, NULL, &pos, NULL);
-      x = pos.x;
-      y = pos.y;
-    }
-
-  return meta_display_begin_grab_op (window->display,
-                                     window,
-                                     op,
-                                     timestamp,
-                                     x, y);
 }
 
 void
@@ -7823,6 +7820,7 @@ meta_window_find_tile_match (MetaWindow   *window,
     {
       MetaWindow *above, *bottommost, *topmost;
       MetaRectangle above_rect, bottommost_rect, topmost_rect;
+      MetaWindowDrag *window_drag;
 
       if (meta_stack_windows_cmp (window->display->stack, match, window) > 0)
         {
@@ -7838,14 +7836,18 @@ meta_window_find_tile_match (MetaWindow   *window,
       meta_window_get_frame_rect (bottommost, &bottommost_rect);
       meta_window_get_frame_rect (topmost, &topmost_rect);
 
+      window_drag =
+        meta_compositor_get_current_window_drag (window->display->compositor);
+
       /*
        * If we are looking for a tile match while actually being tiled,
        * rather than a match for a potential tile mode, then discard
        * windows with too much gap or overlap
        */
       if (window->tile_mode == current_mode &&
-          !(meta_grab_op_is_resizing (window->display->grab_op) &&
+          !(window_drag &&
-            window->display->grab_window == window &&
+            meta_grab_op_is_resizing (meta_window_drag_get_grab_op (window_drag)) &&
+            meta_window_drag_get_window (window_drag) == window &&
             window->tile_match != NULL))
         {
           int threshold = meta_prefs_get_drag_threshold ();

src/core/workspace.c

@@ -576,6 +576,7 @@ meta_workspace_activate_with_focus (MetaWorkspace *workspace,
   MetaWorkspaceLayout layout1, layout2;
   gint num_workspaces, current_space, new_space;
   MetaMotionDirection direction;
+  MetaWindowDrag *window_drag;
 
   g_return_if_fail (META_IS_WORKSPACE (workspace));
   g_return_if_fail (meta_workspace_index (workspace) != -1);
@@ -619,8 +620,11 @@ meta_workspace_activate_with_focus (MetaWorkspace *workspace,
     g_signal_emit_by_name (workspace->manager, "showing-desktop-changed");
 
   move_window = NULL;
-  if (meta_grab_op_is_moving (workspace->display->grab_op))
+  window_drag =
-    move_window = workspace->display->grab_window;
+    meta_compositor_get_current_window_drag (workspace->display->compositor);
+  if (window_drag &&
+      meta_grab_op_is_moving (meta_window_drag_get_grab_op (window_drag)))
+    move_window = meta_window_drag_get_window (window_drag);
 
   if (move_window != NULL)
     {

src/wayland/meta-wayland-pointer.c

@@ -108,17 +108,6 @@ backend_from_pointer (MetaWaylandPointer *pointer)
   return meta_context_get_backend (context);
 }
 
-static MetaDisplay *
-display_from_pointer (MetaWaylandPointer *pointer)
-{
-  MetaWaylandInputDevice *input_device = META_WAYLAND_INPUT_DEVICE (pointer);
-  MetaWaylandSeat *seat = meta_wayland_input_device_get_seat (input_device);
-  MetaWaylandCompositor *compositor = meta_wayland_seat_get_compositor (seat);
-  MetaContext *context = meta_wayland_compositor_get_context (compositor);
-
-  return meta_context_get_display (context);
-}
-
 static MetaWaylandPointerClient *
 meta_wayland_pointer_client_new (void)
 {
@@ -312,7 +301,6 @@ surface_get_effective_window (MetaWaylandSurface *surface)
 static void
 sync_focus_surface (MetaWaylandPointer *pointer)
 {
-  MetaDisplay *display = display_from_pointer (pointer);
   MetaBackend *backend = backend_from_pointer (pointer);
   MetaCursorTracker *cursor_tracker = meta_backend_get_cursor_tracker (backend);
   ClutterBackend *clutter_backend = clutter_get_default_backend ();
@@ -327,16 +315,8 @@ sync_focus_surface (MetaWaylandPointer *pointer)
       return;
     }
 
-  if (display->grab_op == META_GRAB_OP_NONE)
+  const MetaWaylandPointerGrabInterface *interface = pointer->grab->interface;
-    {
+  interface->focus (pointer->grab, pointer->current);
-      const MetaWaylandPointerGrabInterface *interface = pointer->grab->interface;
-      interface->focus (pointer->grab, pointer->current);
-    }
-  else
-    {
-      /* The compositor has a grab, so remove our focus... */
-      meta_wayland_pointer_set_focus (pointer, NULL);
-    }
 }
 
 static void
@@ -476,7 +456,6 @@ default_grab_focus (MetaWaylandPointerGrab *grab,
 {
   MetaWaylandPointer *pointer = grab->pointer;
   MetaWaylandSeat *seat = meta_wayland_pointer_get_seat (pointer);
-  MetaDisplay *display = display_from_pointer (pointer);
   MetaBackend *backend = backend_from_pointer (pointer);
   MetaCursorTracker *cursor_tracker = meta_backend_get_cursor_tracker (backend);
   ClutterBackend *clutter_backend = clutter_get_default_backend ();
@@ -496,9 +475,6 @@ default_grab_focus (MetaWaylandPointerGrab *grab,
   if (pointer->button_count > 0)
     return;
 
-  if (display->grab_op != META_GRAB_OP_NONE)
-    return;
-
   if (surface)
     {
       MetaWindow *window = NULL;

src/wayland/meta-wayland-tablet-tool.c

@@ -50,16 +50,6 @@ backend_from_tool (MetaWaylandTabletTool *tool)
   return meta_context_get_backend (context);
 }
 
-static MetaDisplay *
-display_from_tool (MetaWaylandTabletTool *tool)
-{
-  MetaWaylandCompositor *compositor =
-    meta_wayland_seat_get_compositor (tool->seat->seat);
-  MetaContext *context = meta_wayland_compositor_get_context (compositor);
-
-  return meta_context_get_display (context);
-}
-
 static void
 unbind_resource (struct wl_resource *resource)
 {
@@ -575,7 +565,6 @@ static void
 sync_focus_surface (MetaWaylandTabletTool *tool,
                     const ClutterEvent    *event)
 {
-  MetaDisplay *display = display_from_tool (tool);
   MetaBackend *backend = backend_from_tool (tool);
   ClutterStage *stage = CLUTTER_STAGE (meta_backend_get_stage (backend));
 
@@ -585,15 +574,7 @@ sync_focus_surface (MetaWaylandTabletTool *tool,
       return;
     }
 
-  if (display->grab_op == META_GRAB_OP_NONE)
+  meta_wayland_tablet_tool_set_focus (tool, tool->current, event);
-    {
-      meta_wayland_tablet_tool_set_focus (tool, tool->current, event);
-    }
-  else
-    {
-      /* The compositor has a grab, so remove our focus */
-      meta_wayland_tablet_tool_set_focus (tool, NULL, event);
-    }
 }
 
 static void

src/wayland/meta-wayland-xdg-shell.c

@@ -26,6 +26,7 @@
 #include "wayland/meta-wayland-xdg-shell.h"
 
 #include "backends/meta-logical-monitor.h"
+#include "compositor/compositor-private.h"
 #include "core/boxes-private.h"
 #include "core/window-private.h"
 #include "wayland/meta-wayland-outputs.h"
@@ -685,12 +686,17 @@ fill_states (MetaWaylandXdgToplevel *xdg_toplevel,
   MetaWaylandSurface *surface =
     meta_wayland_surface_role_get_surface (surface_role);
   MetaWindow *window = meta_wayland_surface_get_window (surface);
+  MetaWindowDrag *window_drag;
+
+  window_drag =
+    meta_compositor_get_current_window_drag (window->display->compositor);
 
   if (META_WINDOW_MAXIMIZED (window))
     add_state_value (states, XDG_TOPLEVEL_STATE_MAXIMIZED);
   if (meta_window_is_fullscreen (window))
     add_state_value (states, XDG_TOPLEVEL_STATE_FULLSCREEN);
-  if (meta_grab_op_is_resizing (window->display->grab_op))
+  if (window_drag &&
+      meta_grab_op_is_resizing (meta_window_drag_get_grab_op (window_drag)))
     add_state_value (states, XDG_TOPLEVEL_STATE_RESIZING);
   if (meta_window_appears_focused (window))
     add_state_value (states, XDG_TOPLEVEL_STATE_ACTIVATED);

src/wayland/meta-window-wayland.c

@@ -1125,6 +1125,7 @@ meta_window_wayland_finish_move_resize (MetaWindow              *window,
   MetaWaylandWindowConfiguration *acked_configuration;
   gboolean is_window_being_resized;
   gboolean is_client_resize;
+  MetaWindowDrag *window_drag;
 
   /* new_geom is in the logical pixel coordinate space, but MetaWindow wants its
    * rects to represent what in turn will end up on the stage, i.e. we need to
@@ -1168,9 +1169,13 @@ meta_window_wayland_finish_move_resize (MetaWindow              *window,
 
   flags = META_MOVE_RESIZE_WAYLAND_FINISH_MOVE_RESIZE;
 
+  window_drag = meta_compositor_get_current_window_drag (display->compositor);
+
   /* x/y are ignored when we're doing interactive resizing */
-  is_window_being_resized = (meta_grab_op_is_resizing (display->grab_op) &&
+  is_window_being_resized =
-                             display->grab_window == window);
+    (window_drag &&
+     meta_grab_op_is_resizing (meta_window_drag_get_grab_op (window_drag)) &&
+     meta_window_drag_get_window (window_drag) == window);
 
   rect = (MetaRectangle) {
     .x = window->rect.x,
@@ -1229,8 +1234,9 @@ meta_window_wayland_finish_move_resize (MetaWindow              *window,
                    meta_wayland_window_configuration_free);
   wl_window->last_acked_configuration = g_steal_pointer (&acked_configuration);
 
-  if (window->display->grab_window == window)
+  if (window_drag &&
-    gravity = meta_resize_gravity_from_grab_op (window->display->grab_op);
+      meta_window_drag_get_window (window_drag) == window)
+    gravity = meta_resize_gravity_from_grab_op (meta_window_drag_get_grab_op (window_drag));
   else
     gravity = META_GRAVITY_STATIC;
   meta_window_move_resize_internal (window, flags, gravity, rect);

src/x11/events.c

@@ -970,9 +970,6 @@ handle_input_xevent (MetaX11Display *x11_display,
   switch (input_event->evtype)
     {
     case XI_Enter:
-      if (display->grab_op != META_GRAB_OP_NONE)
-        break;
-
       if (clutter_stage_get_grab_actor (stage) != NULL)
         break;
 
@@ -992,9 +989,6 @@ handle_input_xevent (MetaX11Display *x11_display,
         }
       break;
     case XI_Leave:
-      if (display->grab_op != META_GRAB_OP_NONE)
-        break;
-
       if (clutter_stage_get_grab_actor (stage) != NULL)
         break;
 
@@ -1412,10 +1406,6 @@ handle_other_xevent (MetaX11Display *x11_display,
           guint32 timestamp;
           timestamp = meta_display_get_current_time_roundtrip (display);
 
-          if (display->grab_op != META_GRAB_OP_NONE &&
-              display->grab_window == window)
-            meta_display_end_grab_op (display, timestamp);
-
           if (frame_was_receiver)
             {
               meta_x11_error_trap_push (x11_display);
@@ -1440,11 +1430,6 @@ handle_other_xevent (MetaX11Display *x11_display,
           guint32 timestamp;
           timestamp = meta_display_get_current_time_roundtrip (display);
 
-          if (display->grab_op != META_GRAB_OP_NONE &&
-              display->grab_window == window &&
-              window->frame == NULL)
-            meta_display_end_grab_op (display, timestamp);
-
           if (!frame_was_receiver)
             {
               if (window->unmaps_pending == 0)

src/x11/meta-sync-counter.c

@@ -191,6 +191,7 @@ sync_request_timeout (gpointer data)
 {
   MetaSyncCounter *sync_counter = data;
   MetaWindow *window = sync_counter->window;
+  MetaWindowDrag *window_drag;
 
   sync_counter->sync_request_timeout_id = 0;
 
@@ -205,8 +206,12 @@ sync_request_timeout (gpointer data)
   sync_counter->sync_request_wait_serial = 0;
   meta_compositor_sync_updates_frozen (window->display->compositor, window);
 
-  if (window == window->display->grab_window &&
+  window_drag =
-      meta_grab_op_is_resizing (window->display->grab_op))
+    meta_compositor_get_current_window_drag (window->display->compositor);
+
+  if (window_drag &&
+      window == meta_window_drag_get_window (window_drag) &&
+      meta_grab_op_is_resizing (meta_window_drag_get_grab_op (window_drag)))
     meta_window_x11_check_update_resize (window);
 
   return G_SOURCE_REMOVE;

src/x11/window-x11.c

@@ -1310,8 +1310,8 @@ meta_window_x11_move_resize_internal (MetaWindow                *window,
   gboolean need_resize_frame = FALSE;
   gboolean frame_shape_changed = FALSE;
   gboolean configure_frame_first;
-
   gboolean is_configure_request;
+  MetaWindowDrag *window_drag;
 
   is_configure_request = (flags & META_MOVE_RESIZE_CONFIGURE_REQUEST) != 0;
 
@@ -1495,9 +1495,13 @@ meta_window_x11_move_resize_internal (MetaWindow                *window,
 
   meta_x11_error_trap_push (window->display->x11_display);
 
+  window_drag =
+    meta_compositor_get_current_window_drag (window->display->compositor);
+
   if (mask != 0 &&
-      window == window->display->grab_window &&
+      window_drag &&
-      meta_grab_op_is_resizing (window->display->grab_op))
+      window == meta_window_drag_get_window (window_drag) &&
+      meta_grab_op_is_resizing (meta_window_drag_get_grab_op (window_drag)))
     {
       meta_sync_counter_send_request (&priv->sync_counter);
       if (window->frame)
@@ -2642,6 +2646,7 @@ meta_window_move_resize_request (MetaWindow  *window,
   gboolean in_grab_op;
   MetaMoveResizeFlags flags;
   MetaRectangle buffer_rect;
+  MetaWindowDrag *window_drag;
 
   /* We ignore configure requests while the user is moving/resizing
    * the window, since these represent the app sucking and fighting
@@ -2651,8 +2656,11 @@ meta_window_move_resize_request (MetaWindow  *window,
    * Still have to do the ConfigureNotify and all, but pretend the
    * app asked for the current size/position instead of the new one.
    */
-  in_grab_op = (window->display->grab_window == window &&
+  window_drag =
-                meta_grab_op_is_mouse (window->display->grab_op));
+    meta_compositor_get_current_window_drag (window->display->compositor);
+  in_grab_op = (window_drag &&
+                meta_window_drag_get_window (window_drag) == window &&
+                meta_grab_op_is_mouse (meta_window_drag_get_grab_op (window_drag)));
 
   /* it's essential to use only the explicitly-set fields,
    * and otherwise use our current up-to-date position.
@@ -2716,7 +2724,8 @@ meta_window_move_resize_request (MetaWindow  *window,
   meta_window_get_buffer_rect (window, &buffer_rect);
   width = buffer_rect.width;
   height = buffer_rect.height;
-  if (!in_grab_op || !meta_grab_op_is_resizing (window->display->grab_op))
+  if (!in_grab_op || !window_drag ||
+      !meta_grab_op_is_resizing (meta_window_drag_get_grab_op (window_drag)))
     {
       if (value_mask & CWWidth)
         width = new_width;
@@ -3271,6 +3280,7 @@ meta_window_x11_client_message (MetaWindow *window,
       MetaGrabOp op;
       int button;
       guint32 timestamp;
+      MetaWindowDrag *window_drag;
 
       x_root = event->xclient.data.l[0];
       y_root = event->xclient.data.l[1];
@@ -3327,9 +3337,13 @@ meta_window_x11_client_message (MetaWindow *window,
           break;
         }
 
+      window_drag =
+        meta_compositor_get_current_window_drag (window->display->compositor);
+
       if (action == _NET_WM_MOVERESIZE_CANCEL)
         {
-          meta_display_end_grab_op (window->display, timestamp);
+          if (window_drag)
+            meta_window_drag_end (window_drag);
         }
       else if (op != META_GRAB_OP_NONE &&
           ((window->has_move_func && op == META_GRAB_OP_KEYBOARD_MOVING) ||
@@ -3365,8 +3379,8 @@ meta_window_x11_client_message (MetaWindow *window,
               else if ((button_mask & (1 << 3)) != 0)
                 button = 3;
 
-              if (button == 0)
+              if (button == 0 && window_drag)
-                meta_display_end_grab_op (window->display, timestamp);
+                meta_window_drag_end (window_drag);
             }
           else
             {
@@ -3383,8 +3397,8 @@ meta_window_x11_client_message (MetaWindow *window,
                * drag immediately.
                */
 
-              if ((button_mask & (1 << button)) == 0)
+              if (window_drag && (button_mask & (1 << button)) == 0)
-                meta_display_end_grab_op (window->display, timestamp);
+                meta_window_drag_end (window_drag);
             }
         }
 
@@ -4302,6 +4316,7 @@ meta_window_x11_check_update_resize (MetaWindow *window)
 {
   MetaWindowX11 *window_x11 = META_WINDOW_X11 (window);
   MetaWindowX11Private *priv = meta_window_x11_get_instance_private (window_x11);
+  MetaWindowDrag *window_drag;
 
   if (window->frame &&
       meta_sync_counter_is_waiting (meta_frame_get_sync_counter (window->frame)))
@@ -4310,10 +4325,9 @@ meta_window_x11_check_update_resize (MetaWindow *window)
   if (meta_sync_counter_is_waiting (&priv->sync_counter))
     return;
 
-  meta_window_update_resize (window,
+  window_drag =
-                             window->display->grab_last_edge_resistance_flags,
+    meta_compositor_get_current_window_drag (window->display->compositor);
-                             window->display->grab_latest_motion_x,
+  meta_window_drag_update_resize (window_drag);
-                             window->display->grab_latest_motion_y);
 }
 
 gboolean