[PATCH weston 4/6] xdg-shell: Send an error when the client uses the not-topmost popup

[Jasper St. Pierre]

Either in destroy or get_xdg_popup.
---
 desktop-shell/shell.c  | 21 ++++++++++++++++++++-
 protocol/xdg-shell.xml |  7 +++++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/desktop-shell/shell.c b/desktop-shell/shell.c
index 7650884..9a69657 100644
--- a/desktop-shell/shell.c
+++ b/desktop-shell/shell.c
@@ -224,6 +224,7 @@ struct shell_seat {
 	struct {
 		struct weston_pointer_grab grab;
 		struct weston_touch_grab touch_grab;
+		struct shell_surface *top_surface;
 		struct wl_list surfaces_list;
 		struct wl_client *client;
 		int32_t initial_up;
@@ -3231,6 +3232,7 @@ popup_grab_end(struct weston_pointer *pointer)
 		}
 		wl_list_init(&prev->popup.grab_link);
 		wl_list_init(&shseat->popup_grab.surfaces_list);
+		shseat->popup_grab.top_surface = NULL;
 	}
 }
 
@@ -3291,6 +3293,8 @@ add_popup_grab(struct shell_surface *shsurf, struct shell_seat *shseat, int32_t
 	} else {
 		wl_list_insert(&shseat->popup_grab.surfaces_list, &shsurf->popup.grab_link);
 	}
+
+	shseat->popup_grab.top_surface = shsurf;
 }
 
 static void
@@ -3298,6 +3302,13 @@ remove_popup_grab(struct shell_surface *shsurf)
 {
 	struct shell_seat *shseat = shsurf->popup.shseat;
 
+	if (shell_surface_is_xdg_popup(shsurf) && shseat->popup_grab.top_surface != shsurf) {
+		wl_resource_post_error(shsurf->resource,
+				       XDG_POPUP_ERROR_NOT_THE_TOPMOST_POPUP,
+				       "xdg_popup was destroyed while it was not the topmost popup.");
+		return;
+	}
+
 	wl_list_remove(&shsurf->popup.grab_link);
 	wl_list_init(&shsurf->popup.grab_link);
 	if (wl_list_empty(&shseat->popup_grab.surfaces_list)) {
@@ -3945,7 +3956,15 @@ create_xdg_popup(struct shell_client *owner, void *shell,
 		 uint32_t serial,
 		 int32_t x, int32_t y)
 {
-	struct shell_surface *shsurf;
+	struct shell_surface *shsurf, *parent_shsurf;
+
+	parent_shsurf = get_shell_surface(parent);
+	if (seat->popup_grab.top_surface != NULL && seat->popup_grab.top_surface != parent_shsurf) {
+		wl_resource_post_error(owner->resource,
+				       XDG_POPUP_ERROR_NOT_THE_TOPMOST_POPUP,
+				       "xdg_popup was not created on the topmost popup");
+		return NULL;
+	}
 
 	shsurf = create_common_surface(owner, shell, surface, client);
 	if (!shsurf)
diff --git a/protocol/xdg-shell.xml b/protocol/xdg-shell.xml
index 4414d46..360179d 100644
--- a/protocol/xdg-shell.xml
+++ b/protocol/xdg-shell.xml
@@ -398,6 +398,13 @@
       xdg_popup surfaces are always transient for another surface.
     </description>
 
+    <enum name="error">
+      <description summary="xdg_popup error values">
+	These errors can be emitted in response to xdg_popup requests.
+      </description>
+      <entry name="not_the_topmost_popup" value="0" summary="The client tried to destroy a non-toplevel popup"/>
+    </enum>
+
     <request name="destroy" type="destructor">
       <description summary="remove xdg_surface interface">
 	The xdg_surface interface is removed from the wl_surface object
-- 
2.1.0