[mutter/wip/carlosg/broadcast-offers-3.36: 1/2] wayland: Send clipboard offers to all data devices from the same client

[Carlos Garnacho <carlosg src gnome org>]

commit 7b96ccce34e8a936634eb4582f57fce67b1c75cd
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
    
    (cherry-pick of commit 7e4e3714663952a69ba0a26662841fc5c0cb266c)
    
    https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1262

 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 fb5992ea0..37f23e7b3 100644
--- a/src/wayland/meta-wayland-data-device.c
+++ b/src/wayland/meta-wayland-data-device.c
@@ -108,6 +108,30 @@ static struct wl_resource * create_and_send_primary_offer   (MetaWaylandDataDevi
                                                              struct wl_resource    *target);
 static struct wl_resource * meta_wayland_data_source_get_resource (MetaWaylandDataSource *source);
 
+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)
 {
@@ -901,6 +925,12 @@ 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);
@@ -1860,10 +1890,7 @@ owner_changed_cb (MetaSelection         *selection,
     }
   else 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;
 
@@ -1998,6 +2025,7 @@ void
 meta_wayland_data_device_init (MetaWaylandDataDevice *data_device)
 {
   wl_list_init (&data_device->resource_list);
+  wl_list_init (&data_device->focus_resource_list);
   wl_list_init (&data_device->primary_resource_list);
 }
 
@@ -2080,14 +2108,20 @@ 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 027dafc54..7ebaca326 100644
--- a/src/wayland/meta-wayland-data-device.h
+++ b/src/wayland/meta-wayland-data-device.h
@@ -63,6 +63,7 @@ struct _MetaWaylandDataDevice
   MetaWaylandDataSource *primary_data_source;
   struct wl_listener selection_data_source_listener;
   struct wl_list resource_list;
+  struct wl_list focus_resource_list;
   struct wl_list primary_resource_list;
   MetaWaylandDragGrab *current_grab;
   struct wl_client *focus_client;