mutter/0007-wayland-Set-dummy-selection-source-on-.set_selection.patch

From 84cc89e19a2765f9d011c39ed6cc37689a7cc34e Mon Sep 17 00:00:00 2001
From: Carlos Garnacho <carlosg@gnome.org>
Date: Fri, 11 Oct 2019 18:43:00 +0200
Subject: [PATCH 7/8] wayland: Set dummy selection source on
 .set_selection(null)

Requesting a selection with a NULL data source means "unset the clipboard",
but internally we use an unset clipboard as the indication that the
clipboard manager should take over.

Moreover, this unset request may go unheard if the current owner is someone
else than the MetaWaylandDataDevice.

Instead, set a dummy data source with no mimetypes nor data, this both
prevents the clipboard manager from taking over and ensures the selection
is replaced with it.

The MetaSelectionSourceMemory was also added some checks to allow for this
dummy mode.

Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/793
---
 src/core/meta-selection-source-memory.c |  5 ++++-
 src/wayland/meta-wayland-data-device.c  | 25 +++++++++++++------------
 2 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/src/core/meta-selection-source-memory.c b/src/core/meta-selection-source-memory.c
index 04b7f39a3..c8b0c83f5 100644
--- a/src/core/meta-selection-source-memory.c
+++ b/src/core/meta-selection-source-memory.c
@@ -76,6 +76,9 @@ meta_selection_source_memory_get_mimetypes (MetaSelectionSource *source)
 {
   MetaSelectionSourceMemory *source_mem = META_SELECTION_SOURCE_MEMORY (source);
 
+  if (!source_mem->mimetype)
+    return NULL;
+
   return g_list_prepend (NULL, g_strdup (source_mem->mimetype));
 }
 
@@ -84,7 +87,7 @@ meta_selection_source_memory_finalize (GObject *object)
 {
   MetaSelectionSourceMemory *source_mem = META_SELECTION_SOURCE_MEMORY (object);
 
-  g_bytes_unref (source_mem->content);
+  g_clear_pointer (&source_mem->content, g_bytes_unref);
   g_free (source_mem->mimetype);
 
   G_OBJECT_CLASS (meta_selection_source_memory_parent_class)->finalize (object);
diff --git a/src/wayland/meta-wayland-data-device.c b/src/wayland/meta-wayland-data-device.c
index 0044a80b8..f95be0bf8 100644
--- a/src/wayland/meta-wayland-data-device.c
+++ b/src/wayland/meta-wayland-data-device.c
@@ -36,6 +36,7 @@
 #include <unistd.h>
 
 #include "compositor/meta-dnd-actor-private.h"
+#include "meta/meta-selection-source-memory.h"
 #include "wayland/meta-selection-source-wayland-private.h"
 #include "wayland/meta-wayland-dnd-surface.h"
 #include "wayland/meta-wayland-pointer.h"
@@ -1627,6 +1628,7 @@ meta_wayland_data_device_set_selection (MetaWaylandDataDevice *data_device,
   MetaWaylandSeat *seat = wl_container_of (data_device, seat, data_device);
   struct wl_resource *data_device_resource;
   struct wl_client *focus_client;
+  MetaSelectionSource *selection_source;
 
   if (data_device->selection_data_source &&
       data_device->selection_serial - serial < UINT32_MAX / 2)
@@ -1646,23 +1648,22 @@ meta_wayland_data_device_set_selection (MetaWaylandDataDevice *data_device,
 
   if (source)
     {
-      MetaSelectionSource *selection_source;
-
       meta_wayland_data_source_set_seat (source, seat);
       g_object_weak_ref (G_OBJECT (source),
                          selection_data_source_destroyed,
                          data_device);
 
       selection_source = meta_selection_source_wayland_new (source);
-      set_selection_source (data_device, META_SELECTION_CLIPBOARD,
-                            selection_source);
-      g_object_unref (selection_source);
     }
   else
     {
-      unset_selection_source (data_device, META_SELECTION_CLIPBOARD);
+      selection_source = g_object_new (META_TYPE_SELECTION_SOURCE_MEMORY, NULL);
     }
 
+  set_selection_source (data_device, META_SELECTION_CLIPBOARD,
+                        selection_source);
+  g_object_unref (selection_source);
+
   focus_client = meta_wayland_keyboard_get_focus_client (seat->keyboard);
   if (focus_client)
     {
@@ -1748,6 +1749,7 @@ meta_wayland_data_device_set_primary (MetaWaylandDataDevice *data_device,
   MetaWaylandSeat *seat = wl_container_of (data_device, seat, data_device);
   struct wl_resource *data_device_resource;
   struct wl_client *focus_client;
+  MetaSelectionSource *selection_source;
 
   if (META_IS_WAYLAND_DATA_SOURCE_PRIMARY (source))
     {
@@ -1777,23 +1779,22 @@ meta_wayland_data_device_set_primary (MetaWaylandDataDevice *data_device,
 
   if (source)
     {
-      MetaSelectionSource *selection_source;
-
       meta_wayland_data_source_set_seat (source, seat);
       g_object_weak_ref (G_OBJECT (source),
                          primary_source_destroyed,
                          data_device);
 
       selection_source = meta_selection_source_wayland_new (source);
-      set_selection_source (data_device, META_SELECTION_PRIMARY,
-                            selection_source);
-      g_object_unref (selection_source);
     }
   else
     {
-      unset_selection_source (data_device, META_SELECTION_PRIMARY);
+      selection_source = g_object_new (META_TYPE_SELECTION_SOURCE_MEMORY, NULL);
     }
 
+  set_selection_source (data_device, META_SELECTION_PRIMARY,
+                        selection_source);
+  g_object_unref (selection_source);
+
   focus_client = meta_wayland_keyboard_get_focus_client (seat->keyboard);
   if (focus_client)
     {
-- 
2.23.0