xdg-shell: Add support for popup repositioning

This adds support for xdg-shell v3, which adds support for repositioning
popups. This adds support for explicit popup repositioning, as weston
doesn't yet apply any constraining to popups, thus cannot implicitly
reposition.

Signed-off-by: Jonas Ådahl <jadahl@gmail.com>
Tested-by: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>

libweston-desktop/xdg-shell.c

@@ -37,6 +37,7 @@
 
 #include <libweston-desktop/libweston-desktop.h>
 #include "internal.h"
+#include "shared/helpers.h"
 
 /************************************************************************************
  * WARNING: This file implements the stable xdg shell protocol.
@@ -44,7 +45,7 @@
  * implements the older unstable xdg shell v6 protocol.
  ************************************************************************************/
 
-#define WD_XDG_SHELL_PROTOCOL_VERSION 1
+#define WD_XDG_SHELL_PROTOCOL_VERSION 3
 
 static const char *weston_desktop_xdg_toplevel_role = "xdg_toplevel";
 static const char *weston_desktop_xdg_popup_role = "xdg_popup";
@@ -129,10 +130,15 @@ struct weston_desktop_xdg_popup {
 	struct weston_desktop_xdg_surface *parent;
 	struct weston_desktop_seat *seat;
 	struct weston_geometry geometry;
+
+	bool pending_reposition;
+	uint32_t pending_reposition_token;
 };
 
-#define weston_desktop_surface_role_biggest_size (sizeof(struct weston_desktop_xdg_toplevel))
-#define weston_desktop_surface_configure_biggest_size (sizeof(struct weston_desktop_xdg_toplevel))
+#define weston_desktop_surface_role_biggest_size \
+	MAX(sizeof(struct weston_desktop_xdg_toplevel), \
+	    sizeof(struct weston_desktop_xdg_popup))
+#define weston_desktop_surface_configure_biggest_size weston_desktop_surface_role_biggest_size
 
 
 static struct weston_geometry
@@ -301,6 +307,27 @@ weston_desktop_xdg_positioner_protocol_set_offset(struct wl_client *wl_client,
 	positioner->offset.y = y;
 }
 
+static void
+weston_desktop_xdg_positioner_protocol_set_reactive(struct wl_client *wl_client,
+						    struct wl_resource *resource)
+{
+}
+
+static void
+weston_desktop_xdg_positioner_protocol_set_parent_size(struct wl_client *wl_client,
+						       struct wl_resource *resource,
+						       int32_t width,
+						       int32_t height)
+{
+}
+
+static void
+weston_desktop_xdg_positioner_protocol_set_parent_configure(struct wl_client *wl_client,
+							    struct wl_resource *resource,
+							    uint32_t serial)
+{
+}
+
 static void
 weston_desktop_xdg_positioner_destroy(struct wl_resource *resource)
 {
@@ -318,6 +345,9 @@ static const struct xdg_positioner_interface weston_desktop_xdg_positioner_imple
 	.set_gravity               = weston_desktop_xdg_positioner_protocol_set_gravity,
 	.set_constraint_adjustment = weston_desktop_xdg_positioner_protocol_set_constraint_adjustment,
 	.set_offset                = weston_desktop_xdg_positioner_protocol_set_offset,
+	.set_reactive              = weston_desktop_xdg_positioner_protocol_set_reactive,
+	.set_parent_size           = weston_desktop_xdg_positioner_protocol_set_parent_size,
+	.set_parent_configure      = weston_desktop_xdg_positioner_protocol_set_parent_configure,
 };
 
 static void
@@ -852,9 +882,60 @@ weston_desktop_xdg_popup_protocol_grab(struct wl_client *wl_client,
 					  popup->seat, serial);
 }
 
+static bool
+is_positioner_valid(struct weston_desktop_xdg_positioner *positioner)
+{
+	/* Checking whether the size and anchor rect both have a positive size
+	 * is enough to verify both have been correctly set */
+	if (positioner->size.width == 0 || positioner->anchor_rect.width == 0)
+		return false;
+
+	if (positioner->anchor_rect.height == 0)
+		return false;
+
+	return true;
+}
+
+static void
+weston_desktop_xdg_popup_protocol_reposition(struct wl_client *wl_client,
+					     struct wl_resource *resource,
+					     struct wl_resource *positioner_resource,
+					     uint32_t token)
+{
+	struct weston_desktop_surface *dsurface =
+		wl_resource_get_user_data(resource);
+	struct weston_desktop_xdg_popup *popup =
+		weston_desktop_surface_get_implementation_data(dsurface);
+	struct weston_desktop_xdg_positioner *positioner =
+		wl_resource_get_user_data(positioner_resource);
+	struct weston_desktop_surface *parent_dsurface;
+
+	if (!is_positioner_valid(positioner)) {
+		wl_resource_post_error(resource,
+				       XDG_WM_BASE_ERROR_INVALID_POSITIONER,
+				       "positioner object is not complete");
+		return;
+	}
+
+	parent_dsurface = popup->parent->desktop_surface;
+	popup->geometry =
+		weston_desktop_xdg_positioner_get_geometry(positioner,
+							   dsurface,
+							   parent_dsurface);
+	popup->pending_reposition = true;
+	popup->pending_reposition_token = token;
+	if (popup->committed)
+		weston_desktop_xdg_surface_schedule_configure(&popup->base);
+}
+
 static void
 weston_desktop_xdg_popup_send_configure(struct weston_desktop_xdg_popup *popup)
 {
+	if (popup->pending_reposition) {
+		popup->pending_reposition = false;
+		xdg_popup_send_repositioned(popup->resource,
+					    popup->pending_reposition_token);
+	}
 	xdg_popup_send_configure(popup->resource,
 				 popup->geometry.x,
 				 popup->geometry.y,
@@ -887,6 +968,16 @@ static void
 weston_desktop_xdg_popup_update_position(struct weston_desktop_surface *dsurface,
 					 void *user_data)
 {
+	struct weston_desktop_xdg_popup *popup =
+		weston_desktop_surface_get_implementation_data(dsurface);
+	struct weston_desktop_surface *parent_dsurface;
+
+	parent_dsurface = popup->parent->desktop_surface;
+	weston_desktop_surface_set_relative_to(popup->base.desktop_surface,
+					       parent_dsurface,
+					       popup->geometry.x,
+					       popup->geometry.y,
+					       true);
 }
 
 static void
@@ -932,6 +1023,7 @@ weston_desktop_xdg_popup_resource_destroy(struct wl_resource *resource)
 static const struct xdg_popup_interface weston_desktop_xdg_popup_implementation = {
 	.destroy             = weston_desktop_destroy_request,
 	.grab                = weston_desktop_xdg_popup_protocol_grab,
+	.reposition          = weston_desktop_xdg_popup_protocol_reposition,
 };
 
 static void
@@ -1110,10 +1202,7 @@ weston_desktop_xdg_surface_protocol_get_popup(struct wl_client *wl_client,
 	parent_surface = wl_resource_get_user_data(parent_resource);
 	parent = weston_desktop_surface_get_implementation_data(parent_surface);
 
-	/* Checking whether the size and anchor rect both have a positive size
-	 * is enough to verify both have been correctly set */
-	if (positioner->size.width == 0 || positioner->anchor_rect.width == 0 ||
-	    positioner->anchor_rect.height == 0) {
+	if (!is_positioner_valid(positioner)) {
 		wl_resource_post_error(resource,
 				       XDG_WM_BASE_ERROR_INVALID_POSITIONER,
 				       "positioner object is not complete");