Fix xdg-positioner implementation

* compositor.h (struct _Positioner): New struct.
* positioner.c (struct _Positioner): Move to compositor.h.
(RetainPositioner, ReleasePositioner): Remove functions.
(HandleResourceDestroy): Destroy positioner instead.
(XLCreateXdgPositioner): Remove reference-counting logic.
(XLRetainPositioner, XLReleasePositioner): Delete functions.
(XLPositionerIsReactive): Delete function.
* xdg_popup.c (struct _XdgPopup): Make positioner a struct
instead of a pointer.
(DestroyBacking, InternalReposition, Reposition)
(HandleParentConfigure, HandleParentResize, XLGetXdgPopup): Copy
positioner instead of taking a reference.

compositor.h

@@ -1395,13 +1395,31 @@ extern void XLXdgRoleReplyPing (Role *);
 
 typedef struct _Positioner Positioner;
 
+/* This structure is public because positioners must be copied into
+   xdg_popups.  */
+
+struct _Positioner
+{
+  /* The fields below mean what they do in the xdg_shell protocol
+     spec.  */
+  int width, height;
+  int anchor_x, anchor_y;
+  int anchor_width, anchor_height;
+  unsigned int anchor, gravity, constraint;
+  int offset_x, offset_y;
+  Bool reactive;
+  int parent_width, parent_height;
+  uint32_t constraint_adjustment;
+
+  /* The wl_resource corresponding to this positioner.  Not valid when
+     embedded in i.e. an xdg_popup.  */
+  struct wl_resource *resource;
+};
+
 extern void XLCreateXdgPositioner (struct wl_client *, struct wl_resource *,
 				   uint32_t);
 extern void XLPositionerCalculateGeometry (Positioner *, Role *, int *, int *,
 					   int *, int *);
-extern void XLRetainPositioner (Positioner *);
-extern void XLReleasePositioner (Positioner *);
-extern Bool XLPositionerIsReactive (Positioner *);
 extern void XLCheckPositionerComplete (Positioner *);
 
 /* Defined in xdg_toplevel.c.  */

positioner.c

@@ -61,26 +61,6 @@ enum _AnchorGravity
     AnchorGravityBottomRight,
   };
 
-struct _Positioner
-{
-  /* The fields below mean what they do in the xdg_shell protocol
-     spec.  */
-  int width, height;
-  int anchor_x, anchor_y;
-  int anchor_width, anchor_height;
-  unsigned int anchor, gravity, constraint;
-  int offset_x, offset_y;
-  Bool reactive;
-  int parent_width, parent_height;
-  uint32_t constraint_adjustment;
-
-  /* The wl_resource corresponding to this positioner.  */
-  struct wl_resource *resource;
-
-  /* The number of references to this positioner.  */
-  int refcount;
-};
-
 /* Surface used to handle scaling during constraint adjustment
    calculation.  */
 static double scale_adjustment_factor;
@@ -226,28 +206,13 @@ static const struct xdg_positioner_interface xdg_positioner_impl =
     .set_parent_configure = SetParentConfigure,
   };
 
-static void
-RetainPositioner (Positioner *positioner)
-{
-  positioner->refcount++;
-}
-
-static void
-ReleasePositioner (Positioner *positioner)
-{
-  if (--positioner->refcount)
-    return;
-
-  XLFree (positioner);
-}
-
 static void
 HandleResourceDestroy (struct wl_resource *resource)
 {
   Positioner *positioner;
 
   positioner = wl_resource_get_user_data (resource);
-  ReleasePositioner (positioner);
+  XLFree (positioner);
 }
 
 static void
@@ -920,25 +885,6 @@ XLCreateXdgPositioner (struct wl_client *client, struct wl_resource *resource,
 				  &xdg_positioner_impl,
 				  positioner,
 				  HandleResourceDestroy);
-  RetainPositioner (positioner);
-}
-
-void
-XLRetainPositioner (Positioner *positioner)
-{
-  RetainPositioner (positioner);
-}
-
-void
-XLReleasePositioner (Positioner *positioner)
-{
-  ReleasePositioner (positioner);
-}
-
-Bool
-XLPositionerIsReactive (Positioner *positioner)
-{
-  return positioner->reactive;
 }
 
 void

xdg_popup.c

@@ -77,7 +77,7 @@ struct _XdgPopup
   uint32_t conf_serial, position_serial;
 
   /* The associated positioner.  */
-  Positioner *positioner;
+  Positioner positioner;
 
   /* Any pending seat on which a grab should be asserted.  */
   Seat *pending_grab_seat;
@@ -138,8 +138,7 @@ DestroyBacking (XdgPopup *popup)
   if (popup->pending_callback_key)
     XLSeatCancelDestroyListener (popup->pending_callback_key);
 
-  /* Release the positioner and free the popup.  */
+  /* Free the popup.  */
-  XLReleasePositioner (popup->positioner);
   XLFree (popup);
 }
 
@@ -449,7 +448,7 @@ InternalReposition (XdgPopup *popup)
   if (!popup->role || !popup->parent)
     return;
 
-  XLPositionerCalculateGeometry (popup->positioner,
+  XLPositionerCalculateGeometry (&popup->positioner,
 				 popup->parent, &x, &y,
 				 &width, &height);
 
@@ -664,16 +663,17 @@ Reposition (struct wl_client *client, struct wl_resource *resource,
 	    struct wl_resource *positioner_resource, uint32_t token)
 {
   XdgPopup *popup;
+  Positioner *positioner;
 
   popup = wl_resource_get_user_data (resource);
 
-  XLReleasePositioner (popup->positioner);
-  popup->positioner
-    = wl_resource_get_user_data (positioner_resource);
-  XLRetainPositioner (popup->positioner);
-
   /* Make sure that the positioner is complete.  */
-  XLCheckPositionerComplete (popup->positioner);
+  positioner = wl_resource_get_user_data (positioner_resource);
+  XLCheckPositionerComplete (positioner);
+
+  /* Copy the positioner to the popup.  */
+  popup->positioner = *positioner;
+  popup->positioner.resource = NULL;
 
   xdg_popup_send_repositioned (resource, token);
   InternalReposition (popup);
@@ -750,7 +750,7 @@ HandleParentConfigure (void *data, XEvent *xevent)
 
   popup = data;
 
-  if (XLPositionerIsReactive (popup->positioner))
+  if (popup->positioner.reactive)
     InternalReposition (popup);
 }
 
@@ -761,7 +761,7 @@ HandleParentResize (void *data)
 
   popup = data;
 
-  if (XLPositionerIsReactive (popup->positioner))
+  if (popup->positioner.reactive)
     InternalReposition (popup);
 }
 
@@ -784,11 +784,12 @@ static const struct xdg_popup_interface xdg_popup_impl =
 void
 XLGetXdgPopup (struct wl_client *client, struct wl_resource *resource,
 	       uint32_t id, struct wl_resource *parent_resource,
-	       struct wl_resource *positioner)
+	       struct wl_resource *positioner_resource)
 {
   XdgPopup *popup;
   Role *role, *parent;
   void *key;
+  Positioner *positioner;
 
   popup = XLSafeMalloc (sizeof *popup);
   role = wl_resource_get_user_data (resource);
@@ -831,11 +832,19 @@ XLGetXdgPopup (struct wl_client *client, struct wl_resource *resource,
       popup->reconstrain_callback_key = key;
     }
 
-  popup->positioner = wl_resource_get_user_data (positioner);
-  XLRetainPositioner (popup->positioner);
-
   /* Make sure that the positioner is complete.  */
-  XLCheckPositionerComplete (popup->positioner);
+  positioner = wl_resource_get_user_data (positioner_resource);
+  XLCheckPositionerComplete (positioner);
+
+  /* Save the positioner into the popup.  The spec says:
+
+      At the time of the request, the compositor makes a copy of the
+      rules specified by the xdg_positioner. Thus, after the request
+      is complete the xdg_positioner object can be destroyed or
+      reused; further changes to the object will have no effect on
+      previous usages.  */
+  popup->positioner = *positioner;
+  popup->positioner.resource = NULL;
 
   wl_resource_set_implementation (popup->resource, &xdg_popup_impl,
 				  popup, HandleResourceDestroy);