[mutter/gnome-3-36] wayland: Send clipboard offers to all data devices from the same client

[Robert Mader <rmader src gnome org>]

commit 1ec91cc8eef1db353d852fc4c212cae3a9cb1aee
Author: Carlos Garnacho <carlosg gnome org>
Date:   Wed May 13 16:36:13 2020 +0200

    wayland: Send clipboard offers to all data devices from the same client
    
    Make the data device track the keyboard focus, and use that list to
    forward the clipboard selection to all data devices from the same
    client.
    
    This is however not the case of DnD data offers, as the semantics
    of multiple in-flight offers is unclear.
    
    Fixes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1250
    
    https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1253
    
    (cherry picked from commit 7e4e3714663952a69ba0a26662841fc5c0cb266c)

 src/wayland/meta-wayland-data-device.c | 46 +++++++++++++++++++++++++++++-----
 src/wayland/meta-wayland-data-device.h |  1 +
 2 files changed, 41 insertions(+), 6 deletions(-)
---
diff --git a/src/wayland/meta-wayland-data-device.c b/src/wayland/meta-wayland-data-device.c
index 98831e1c69..daf2968532 100644
--- a/src/wayland/meta-wayland-data-device.c
+++ b/src/wayland/meta-wayland-data-device.c
@@ -53,6 +53,30 @@ drag_grab_data_source_destroyed (gpointer data, GObject *where_the_object_was);
 static struct wl_resource * create_and_send_clipboard_offer (MetaWaylandDataDevice *data_device,
                                                              struct wl_resource    *target);
 
+static void
+move_resources (struct wl_list *destination,
+                struct wl_list *source)
+{
+  wl_list_insert_list (destination, source);
+  wl_list_init (source);
+}
+
+static void
+move_resources_for_client (struct wl_list   *destination,
+                          struct wl_list   *source,
+                          struct wl_client *client)
+{
+  struct wl_resource *resource, *tmp;
+  wl_resource_for_each_safe (resource, tmp, source)
+    {
+      if (wl_resource_get_client (resource) == client)
+        {
+          wl_list_remove (wl_resource_get_link (resource));
+          wl_list_insert (destination, wl_resource_get_link (resource));
+        }
+    }
+}
+
 static void
 unbind_resource (struct wl_resource *resource)
 {
@@ -251,6 +275,12 @@ meta_wayland_drag_grab_set_focus (MetaWaylandDragGrab *drag_grab,
   client = wl_resource_get_client (surface->resource);
 
   data_device_resource = wl_resource_find_for_client (&seat->data_device.resource_list, client);
+  if (!data_device_resource)
+    {
+      data_device_resource =
+        wl_resource_find_for_client (&seat->data_device.focus_resource_list,
+                                     client);
+    }
 
   if (source && data_device_resource)
     offer = create_and_send_dnd_offer (source, data_device_resource);
@@ -948,10 +978,7 @@ owner_changed_cb (MetaSelection         *selection,
 
   if (selection_type == META_SELECTION_CLIPBOARD)
     {
-      data_device_resource =
-        wl_resource_find_for_client (&data_device->resource_list, focus_client);
-
-      if (data_device_resource)
+      wl_resource_for_each (data_device_resource, &data_device->focus_resource_list)
         {
           struct wl_resource *offer = NULL;
 
@@ -1021,6 +1048,7 @@ void
 meta_wayland_data_device_init (MetaWaylandDataDevice *data_device)
 {
   wl_list_init (&data_device->resource_list);
+  wl_list_init (&data_device->focus_resource_list);
 }
 
 static struct wl_resource *
@@ -1063,14 +1091,20 @@ meta_wayland_data_device_set_keyboard_focus (MetaWaylandDataDevice *data_device)
     return;
 
   data_device->focus_client = focus_client;
+  move_resources (&data_device->resource_list,
+                  &data_device->focus_resource_list);
 
   if (!focus_client)
     return;
 
-  data_device_resource = wl_resource_find_for_client (&data_device->resource_list, focus_client);
-  if (data_device_resource)
+  move_resources_for_client (&data_device->focus_resource_list,
+                             &data_device->resource_list,
+                             focus_client);
+
+  wl_resource_for_each (data_device_resource, &data_device->focus_resource_list)
     {
       struct wl_resource *offer;
+
       offer = create_and_send_clipboard_offer (data_device, data_device_resource);
       wl_data_device_send_selection (data_device_resource, offer);
     }
diff --git a/src/wayland/meta-wayland-data-device.h b/src/wayland/meta-wayland-data-device.h
index eb2ff6fd25..8408933894 100644
--- a/src/wayland/meta-wayland-data-device.h
+++ b/src/wayland/meta-wayland-data-device.h
@@ -41,6 +41,7 @@ struct _MetaWaylandDataDevice
   MetaWaylandDataSource *selection_data_source;
   MetaWaylandDataSource *dnd_data_source;
   struct wl_list resource_list;
+  struct wl_list focus_resource_list;
   MetaWaylandDragGrab *current_grab;
   struct wl_client *focus_client;