backends: Unify touch sequence to slot conversion

We had code in both backends that sort of independently associated
sequences to slots. Make both transform slots to sequences the same
way, so they may share the implementation convert those back to slots.

This helper now lives in Clutter API.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1623>

10 files changed, 18 insertions, 37 deletions

diff --git a/clutter/clutter/clutter-event.c b/clutter/clutter/clutter-event.c
index 793884f00..19ec29f32 100644
--- a/clutter/clutter/clutter-event.c
+++ b/clutter/clutter/clutter-event.c
@@ -2134,3 +2134,11 @@ clutter_event_get_event_code (const ClutterEvent *event)
 
   return 0;
 }
+
+int32_t
+clutter_event_sequence_get_slot (const ClutterEventSequence *sequence)
+{
+  g_return_val_if_fail (sequence != NULL, -1);
+
+  return GPOINTER_TO_INT (sequence) - 1;
+}
diff --git a/clutter/clutter/clutter-event.h b/clutter/clutter/clutter-event.h
index 5ff8ae8f9..7c3d36463 100644
--- a/clutter/clutter/clutter-event.h
+++ b/clutter/clutter/clutter-event.h
@@ -788,6 +788,9 @@ gboolean                 clutter_event_get_pad_event_details         (const Clut
 CLUTTER_EXPORT
 uint32_t                 clutter_event_get_event_code                (const ClutterEvent     *event);
 
+CLUTTER_EXPORT
+int32_t                  clutter_event_sequence_get_slot (const ClutterEventSequence *sequence);
+
 G_END_DECLS
 
 #endif /* __CLUTTER_EVENT_H__ */
diff --git a/src/backends/native/meta-event-native.c b/src/backends/native/meta-event-native.c
index b7e719468..8d59e6287 100644
--- a/src/backends/native/meta-event-native.c
+++ b/src/backends/native/meta-event-native.c
@@ -154,23 +154,3 @@ meta_event_native_get_relative_motion (const ClutterEvent *event,
   else
     return FALSE;
 }
-
-/**
- * meta_event_native_sequence_get_slot:
- * @sequence: a #ClutterEventSequence
- *
- * Retrieves the touch slot triggered by this @sequence
- *
- * Returns: the libinput touch slot.
- *
- * Since: 1.20
- * Stability: unstable
- **/
-int32_t
-meta_event_native_sequence_get_slot (const ClutterEventSequence *sequence)
-{
-  if (!sequence)
-    return -1;
-
-  return GPOINTER_TO_INT (sequence) - 1;
-}
diff --git a/src/backends/native/meta-event-native.h b/src/backends/native/meta-event-native.h
index fc546530a..43cf7b929 100644
--- a/src/backends/native/meta-event-native.h
+++ b/src/backends/native/meta-event-native.h
@@ -42,6 +42,4 @@ gboolean          meta_event_native_get_relative_motion (const ClutterEvent *eve
                                                          double             *dx_unaccel,
                                                          double             *dy_unaccel);
 
-int32_t           meta_event_native_sequence_get_slot (const ClutterEventSequence *sequence);
-
 #endif /* META_EVENT_NATIVE_H */
diff --git a/src/backends/native/meta-seat-impl.c b/src/backends/native/meta-seat-impl.c
index 033a9e3df..bc68e0e99 100644
--- a/src/backends/native/meta-seat-impl.c
+++ b/src/backends/native/meta-seat-impl.c
@@ -2890,7 +2890,7 @@ meta_seat_impl_query_state (MetaSeatImpl         *seat_impl,
       MetaTouchState *touch_state;
       int slot;
 
-      slot = meta_event_native_sequence_get_slot (sequence);
+      slot = clutter_event_sequence_get_slot (sequence);
       touch_state = meta_seat_impl_lookup_touch_state_in_impl (seat_impl, slot);
       if (!touch_state)
         goto out;
diff --git a/src/backends/x11/meta-backend-x11.c b/src/backends/x11/meta-backend-x11.c
index 94a13e7cd..f79b0d6d4 100644
--- a/src/backends/x11/meta-backend-x11.c
+++ b/src/backends/x11/meta-backend-x11.c
@@ -691,7 +691,7 @@ meta_backend_x11_finish_touch_sequence (MetaBackend          *backend,
 
   XIAllowTouchEvents (priv->xdisplay,
                       META_VIRTUAL_CORE_POINTER_ID,
-                      meta_x11_event_sequence_get_touch_detail (sequence),
+                      clutter_event_sequence_get_slot (sequence),
                       DefaultRootWindow (priv->xdisplay), event_mode);
 
   if (state == META_SEQUENCE_REJECTED)
diff --git a/src/backends/x11/meta-event-x11.c b/src/backends/x11/meta-event-x11.c
index 8217e3db7..fa287ead3 100644
--- a/src/backends/x11/meta-event-x11.c
+++ b/src/backends/x11/meta-event-x11.c
@@ -113,11 +113,3 @@ out:
 
   return result;
 }
-
-guint
-meta_x11_event_sequence_get_touch_detail (const ClutterEventSequence *sequence)
-{
-  g_return_val_if_fail (sequence != NULL, 0);
-
-  return GPOINTER_TO_UINT (sequence);
-}
diff --git a/src/backends/x11/meta-event-x11.h b/src/backends/x11/meta-event-x11.h
index 6e0b54eee..ceb363ab0 100644
--- a/src/backends/x11/meta-event-x11.h
+++ b/src/backends/x11/meta-event-x11.h
@@ -28,8 +28,6 @@
 
 #include "clutter/x11/clutter-x11.h"
 
-guint meta_x11_event_sequence_get_touch_detail (const ClutterEventSequence *sequence);
-
 ClutterX11FilterReturn meta_x11_handle_event (XEvent *xevent);
 
 #endif /* META_EVENT_X11_H */
diff --git a/src/backends/x11/meta-seat-x11.c b/src/backends/x11/meta-seat-x11.c
index 1fea4553a..b04da4a97 100644
--- a/src/backends/x11/meta-seat-x11.c
+++ b/src/backends/x11/meta-seat-x11.c
@@ -2213,7 +2213,8 @@ meta_seat_x11_translate_event (MetaSeatX11  *seat,
                                              GUINT_TO_POINTER (xev->detail));
           }
 
-        event->touch.sequence = GUINT_TO_POINTER (xev->detail);
+        /* "NULL" sequences are special cased in clutter */
+        event->touch.sequence = GINT_TO_POINTER (MAX (1, xev->detail + 1));
 
         if (xev->flags & XITouchEmulatingPointer)
           _clutter_event_set_pointer_emulated (event, TRUE);
@@ -2242,7 +2243,8 @@ meta_seat_x11_translate_event (MetaSeatX11  *seat,
         event->touch.type = event->type = CLUTTER_TOUCH_UPDATE;
         event->touch.stage = stage;
         event->touch.time = xev->time;
-        event->touch.sequence = GUINT_TO_POINTER (xev->detail);
+        /* "NULL" sequences are special cased in clutter */
+        event->touch.sequence = GINT_TO_POINTER (MAX (1, xev->detail + 1));
         translate_coords (stage_x11, xev->event_x, xev->event_y, &event->touch.x, &event->touch.y);
 
         clutter_event_set_source_device (event, source_device);
diff --git a/src/wayland/meta-wayland-touch.c b/src/wayland/meta-wayland-touch.c
index bf11fc590..147c3845e 100644
--- a/src/wayland/meta-wayland-touch.c
+++ b/src/wayland/meta-wayland-touch.c
@@ -188,7 +188,7 @@ touch_get_info (MetaWaylandTouch     *touch,
   if (!touch_info && create)
     {
       touch_info = g_new0 (MetaWaylandTouchInfo, 1);
-      touch_info->slot = meta_event_native_sequence_get_slot (sequence);
+      touch_info->slot = clutter_event_sequence_get_slot (sequence);
       g_hash_table_insert (touch->touches, sequence, touch_info);
     }