wayland/xdg-shell: Defer meta_wayland_xdg_positioner_to_placement call

From xdg_surface_constructor_get_popup / xdg_popup_reposition (called
during Wayland protocol processing) to finish_popup_setup /
meta_wayland_xdg_popup_apply_state (called when the popup state is
applied).

This makes sure that the parent window frame rectangle is up to date in
meta_wayland_xdg_positioner_to_placement.

v2:
* Use meta_wayland_surface_state_new () in
  meta_wayland_transaction_add_xdg_popup_reposition.
v3:
* Move xdg_popup_repositioned handling to
  meta_wayland_xdg_popup_apply_state.
v4:
* Do not steal pending->xdg_positioner in
  meta_wayland_xdg_popup_apply_state, fixes leaking the corresponding
  memory.
* Drop MetaWaylandSurfaceState::xdg_popup_repositioned, just use
  ::xdg_positioner.
v5:
* Reformat meta_wayland_xdg_positioner_to_placement calls to stay within
  80 columns. (Jonas Ådahl)

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1880>

6 files changed, 80 insertions, 28 deletions

diff --git a/src/wayland/meta-wayland-surface.c b/src/wayland/meta-wayland-surface.c
index 7beb0ab60..c235ead1c 100644
--- a/src/wayland/meta-wayland-surface.c
+++ b/src/wayland/meta-wayland-surface.c
@@ -502,6 +502,8 @@ meta_wayland_surface_state_set_default (MetaWaylandSurfaceState *state)
   state->subsurface_placement_ops = NULL;
 
   wl_list_init (&state->presentation_feedback_list);
+
+  state->xdg_popup_reposition_token = 0;
 }
 
 static void
@@ -527,6 +529,7 @@ meta_wayland_surface_state_clear (MetaWaylandSurfaceState *state)
   g_clear_pointer (&state->buffer_damage, cairo_region_destroy);
   g_clear_pointer (&state->input_region, cairo_region_destroy);
   g_clear_pointer (&state->opaque_region, cairo_region_destroy);
+  g_clear_pointer (&state->xdg_positioner, g_free);
 
   if (state->buffer)
     g_clear_signal_handler (&state->buffer_destroy_handler_id, state->buffer);
@@ -675,6 +678,13 @@ meta_wayland_surface_state_merge_into (MetaWaylandSurfaceState *from,
   wl_list_insert_list (&to->presentation_feedback_list,
                        &from->presentation_feedback_list);
   wl_list_init (&from->presentation_feedback_list);
+
+  if (from->xdg_positioner)
+    {
+      g_clear_pointer (&to->xdg_positioner, g_free);
+      to->xdg_positioner = g_steal_pointer (&from->xdg_positioner);
+      to->xdg_popup_reposition_token = from->xdg_popup_reposition_token;
+    }
 }
 
 static void
diff --git a/src/wayland/meta-wayland-surface.h b/src/wayland/meta-wayland-surface.h
index 307038a2c..7edddf647 100644
--- a/src/wayland/meta-wayland-surface.h
+++ b/src/wayland/meta-wayland-surface.h
@@ -133,6 +133,10 @@ struct _MetaWaylandSurfaceState
   struct {
     gboolean surface_size_changed;
   } derived;
+
+  /* xdg_popup */
+  MetaWaylandXdgPositioner *xdg_positioner;
+  uint32_t xdg_popup_reposition_token;
 };
 
 struct _MetaWaylandDragDestFuncs
diff --git a/src/wayland/meta-wayland-transaction.c b/src/wayland/meta-wayland-transaction.c
index cc77ea663..6bf0376e9 100644
--- a/src/wayland/meta-wayland-transaction.c
+++ b/src/wayland/meta-wayland-transaction.c
@@ -386,6 +386,27 @@ meta_wayland_transaction_add_subsurface_position (MetaWaylandTransaction *transa
   entry->has_sub_pos = TRUE;
 }
 
+void
+meta_wayland_transaction_add_xdg_popup_reposition (MetaWaylandTransaction *transaction,
+                                                   MetaWaylandSurface     *surface,
+                                                   void                   *xdg_positioner,
+                                                   uint32_t               token)
+{
+  MetaWaylandTransactionEntry *entry;
+  MetaWaylandSurfaceState *state;
+
+  entry = meta_wayland_transaction_ensure_entry (transaction, surface);
+
+  if (entry->state)
+    g_clear_pointer (&entry->state->xdg_positioner, g_free);
+  else
+    entry->state = meta_wayland_surface_state_new ();
+
+  state = entry->state;
+  state->xdg_positioner = xdg_positioner;
+  state->xdg_popup_reposition_token = token;
+}
+
 static void
 meta_wayland_transaction_entry_merge_into (MetaWaylandTransactionEntry *from,
                                            MetaWaylandTransactionEntry *to)
diff --git a/src/wayland/meta-wayland-transaction.h b/src/wayland/meta-wayland-transaction.h
index a42300f8e..98c662001 100644
--- a/src/wayland/meta-wayland-transaction.h
+++ b/src/wayland/meta-wayland-transaction.h
@@ -37,6 +37,11 @@ void meta_wayland_transaction_add_subsurface_position (MetaWaylandTransaction *t
                                                        int                     x,
                                                        int                     y);
 
+void meta_wayland_transaction_add_xdg_popup_reposition (MetaWaylandTransaction *transaction,
+                                                        MetaWaylandSurface     *surface,
+                                                        void                   *xdg_positioner,
+                                                        uint32_t               token);
+
 void meta_wayland_transaction_merge_into (MetaWaylandTransaction *from,
                                           MetaWaylandTransaction *to);
 
diff --git a/src/wayland/meta-wayland-types.h b/src/wayland/meta-wayland-types.h
index 97623df7f..8b1c6f007 100644
--- a/src/wayland/meta-wayland-types.h
+++ b/src/wayland/meta-wayland-types.h
@@ -67,6 +67,8 @@ typedef struct _MetaWaylandActivation MetaWaylandActivation;
 
 typedef struct _MetaWaylandDmaBufManager MetaWaylandDmaBufManager;
 
+typedef struct _MetaWaylandXdgPositioner MetaWaylandXdgPositioner;
+
 typedef struct _MetaXWaylandManager MetaXWaylandManager;
 
 #endif
diff --git a/src/wayland/meta-wayland-xdg-shell.c b/src/wayland/meta-wayland-xdg-shell.c
index 1c2877d3c..240648222 100644
--- a/src/wayland/meta-wayland-xdg-shell.c
+++ b/src/wayland/meta-wayland-xdg-shell.c
@@ -57,7 +57,7 @@ typedef struct _MetaWaylandXdgShellClient
   GList *surface_constructors;
 } MetaWaylandXdgShellClient;
 
-typedef struct _MetaWaylandXdgPositioner
+struct _MetaWaylandXdgPositioner
 {
   MetaRectangle anchor_rect;
   int32_t width;
@@ -76,7 +76,7 @@ typedef struct _MetaWaylandXdgPositioner
 
   gboolean acked_parent_configure;
   uint32_t parent_configure_serial;
-} MetaWaylandXdgPositioner;
+};
 
 typedef struct _MetaWaylandXdgSurfaceConstructor
 {
@@ -130,11 +130,7 @@ struct _MetaWaylandXdgPopup
   struct {
     MetaWaylandSurface *parent_surface;
 
-    /*
-     * The coordinates/dimensions in the placement rule are in logical pixel
-     * coordinate space, i.e. not scaled given what monitor the popup is on.
-     */
-    MetaPlacementRule placement_rule;
+    MetaWaylandXdgPositioner xdg_positioner;
 
     MetaWaylandSeat *grab_seat;
     uint32_t grab_serial;
@@ -623,27 +619,17 @@ xdg_popup_reposition (struct wl_client   *client,
     META_WAYLAND_SURFACE_ROLE (xdg_popup);
   MetaWaylandSurface *surface =
     meta_wayland_surface_role_get_surface (surface_role);
-  MetaWindow *window;
-  MetaWindow *parent_window;
   MetaWaylandXdgPositioner *xdg_positioner;
-  MetaPlacementRule placement_rule;
-
-  window = meta_wayland_surface_get_window (surface);
-  if (!window)
-    return;
-
-  parent_window = meta_wayland_surface_get_window (xdg_popup->parent_surface);
-
-  xdg_positioner = wl_resource_get_user_data (positioner_resource);
-  placement_rule = meta_wayland_xdg_positioner_to_placement (xdg_positioner,
-                                                             parent_window);
+  MetaWaylandTransaction *transaction;
 
-  xdg_popup->pending_reposition_token = token;
-  xdg_popup->pending_repositioned = TRUE;
+  xdg_positioner = g_memdup2 (wl_resource_get_user_data (positioner_resource),
+                              sizeof (MetaWaylandXdgPositioner));
 
-  scale_placement_rule (&placement_rule, surface);
-
-  meta_window_update_placement_rule (window, &placement_rule);
+  transaction = meta_wayland_transaction_new (surface->compositor);
+  meta_wayland_transaction_add_xdg_popup_reposition (transaction, surface,
+                                                     xdg_positioner, token);
+  meta_wayland_transaction_ensure_entry (transaction, xdg_popup->parent_surface);
+  meta_wayland_transaction_commit (transaction);
 }
 
 static const struct xdg_popup_interface meta_wayland_xdg_popup_interface = {
@@ -1080,6 +1066,8 @@ finish_popup_setup (MetaWaylandXdgPopup *xdg_popup)
   uint32_t serial;
   MetaDisplay *display = meta_get_display ();
   MetaWindow *window;
+  MetaWindow *parent_window;
+  MetaPlacementRule placement_rule;
 
   parent_surface = xdg_popup->setup.parent_surface;
   seat = xdg_popup->setup.grab_seat;
@@ -1124,7 +1112,11 @@ finish_popup_setup (MetaWaylandXdgPopup *xdg_popup)
   window = meta_window_wayland_new (display, surface);
   meta_wayland_shell_surface_set_window (shell_surface, window);
 
-  meta_wayland_xdg_popup_place (xdg_popup, &xdg_popup->setup.placement_rule);
+  parent_window = meta_wayland_surface_get_window (parent_surface);
+  placement_rule =
+    meta_wayland_xdg_positioner_to_placement (&xdg_popup->setup.xdg_positioner,
+                                              parent_window);
+  meta_wayland_xdg_popup_place (xdg_popup, &placement_rule);
 
   if (seat)
     {
@@ -1219,6 +1211,25 @@ meta_wayland_xdg_popup_apply_state (MetaWaylandSurfaceRole  *surface_role,
   if (xdg_popup->setup.parent_surface)
     finish_popup_setup (xdg_popup);
 
+  if (pending->xdg_positioner)
+    {
+      MetaWindow *window, *parent_window;
+      MetaPlacementRule placement_rule;
+
+      parent_window = meta_wayland_surface_get_window (xdg_popup->parent_surface);
+      placement_rule =
+        meta_wayland_xdg_positioner_to_placement (pending->xdg_positioner,
+                                                  parent_window);
+
+      xdg_popup->pending_reposition_token = pending->xdg_popup_reposition_token;
+      xdg_popup->pending_repositioned = TRUE;
+
+      scale_placement_rule (&placement_rule, surface);
+
+      window = meta_wayland_surface_get_window (surface);
+      meta_window_update_placement_rule (window, &placement_rule);
+    }
+
   if (!surface->buffer_ref->buffer && xdg_surface_priv->first_buffer_attached)
     {
       meta_wayland_xdg_surface_reset (xdg_surface);
@@ -2040,8 +2051,7 @@ xdg_surface_constructor_get_popup (struct wl_client   *client,
   meta_wayland_xdg_surface_constructor_finalize (constructor, xdg_surface);
 
   xdg_positioner = wl_resource_get_user_data (positioner_resource);
-  xdg_popup->setup.placement_rule =
-    meta_wayland_xdg_positioner_to_placement (xdg_positioner, parent_window);
+  xdg_popup->setup.xdg_positioner = *xdg_positioner;
   xdg_popup->setup.parent_surface = parent_surface;
 }