Add timestamp to pointer image attach request

This lets the server discard requests received after the pointer has
exited and the re-entered a surface.

TODO

@@ -6,12 +6,6 @@ Core wayland protocol
    another menu item), but we need events for the popup menu surface
    as well.
 
- - input_device.attach() should use a timestamp so the server can
-   discard late requests (sending a request to set the pointer image
-   in response to a motion event, the pointer leaves and then reenters
-   the surface, before the server receives the reqest -> the server
-   must discard it).
-
  - The message format has to include information about number of fds
    in the message so we can skip a message correctly.  Or we should
    just give up on trying to recover from unknown messages.

clients/dnd.c

@@ -52,6 +52,7 @@ struct dnd_drag {
 	int hotspot_x, hotspot_y;
 	struct dnd *dnd;
 	struct input *input;
+	uint32_t time;
 };
 
 struct dnd_offer {
@@ -245,7 +246,7 @@ drag_target(void *data,
 		surface = dnd_drag->translucent;
 
 	buffer = display_get_buffer_for_surface(dnd->display, surface);
-	wl_input_device_attach(device, buffer,
+	wl_input_device_attach(device, dnd_drag->time, buffer,
 			       dnd_drag->hotspot_x, dnd_drag->hotspot_y);
 }
 
@@ -488,6 +489,7 @@ dnd_button_handler(struct window *window,
 		dnd_drag = malloc(sizeof *dnd_drag);
 		dnd_drag->dnd = dnd;
 		dnd_drag->input = input;
+		dnd_drag->time = time;
 
 		dnd_drag->opaque =
 			create_drag_cursor(dnd_drag, item, x, y, 1);

clients/window.c

@@ -525,7 +525,7 @@ get_pointer_location(struct window *window, int32_t x, int32_t y)
 }
 
 static void
-set_pointer_image(struct input *input, int pointer)
+set_pointer_image(struct input *input, uint32_t time, int pointer)
 {
 	struct display *display = input->display;
 	struct wl_buffer *buffer;
@@ -564,7 +564,7 @@ set_pointer_image(struct input *input, int pointer)
 		if (input->current_pointer_image == POINTER_DEFAULT)
 			return;
 
-		wl_input_device_attach(input->input_device, NULL, 0, 0);
+		wl_input_device_attach(input->input_device, time, NULL, 0, 0);
 		input->current_pointer_image = POINTER_DEFAULT;
 		return;
 	default:
@@ -577,7 +577,7 @@ set_pointer_image(struct input *input, int pointer)
 	input->current_pointer_image = pointer;
 	surface = display->pointer_surfaces[pointer];
 	buffer = display_get_buffer_for_surface(display, surface);
-	wl_input_device_attach(input->input_device, buffer,
+	wl_input_device_attach(input->input_device, time, buffer,
 			       pointer_images[pointer].hotspot_x,
 			       pointer_images[pointer].hotspot_y);
 }
@@ -603,7 +603,7 @@ window_handle_motion(void *data, struct wl_input_device *input_device,
 						    x, y, sx, sy,
 						    window->user_data);
 
-	set_pointer_image(input, pointer);
+	set_pointer_image(input, time, pointer);
 }
 
 static void
@@ -703,7 +703,7 @@ window_handle_pointer_focus(void *data,
 							    x, y, sx, sy,
 							    window->user_data);
 
-		set_pointer_image(input, pointer);
+		set_pointer_image(input, time, pointer);
 	} else {
 		input->pointer_focus = NULL;
 		input->current_pointer_image = POINTER_UNSET;

compositor/compositor.c

@@ -706,6 +706,7 @@ wlsc_input_device_set_pointer_focus(struct wlsc_input_device *device,
 						    WLSC_POINTER_LEFT_PTR);
 
 	device->pointer_focus = surface;
+	device->pointer_focus_time = time;
 }
 
 static struct wlsc_surface *
@@ -980,12 +981,15 @@ notify_key(struct wlsc_input_device *device,
 static void
 input_device_attach(struct wl_client *client,
 		    struct wl_input_device *device_base,
+		    uint32_t time,
 		    struct wl_buffer *buffer_base, int32_t x, int32_t y)
 {
 	struct wlsc_input_device *device =
 		(struct wlsc_input_device *) device_base;
 	struct wlsc_buffer *buffer = (struct wlsc_buffer *) buffer_base;
 
+	if (time < device->pointer_focus_time)
+		return;
 	if (device->pointer_focus == NULL)
 		return;
 	if (device->pointer_focus->base.client != client &&

compositor/compositor.h

@@ -99,6 +99,7 @@ struct wlsc_input_device {
 	struct wlsc_surface *keyboard_focus;
 	struct wl_array keys;
 	uint32_t modifier_state;
+	uint32_t pointer_focus_time;
 
 	enum wlsc_grab_type grab;
 	struct wlsc_surface *grab_surface;

wayland/Makefile

@@ -49,7 +49,7 @@ scanner :					\
 
 scanner : LDLIBS += $(EXPAT_LIBS)
 
-install : $(libs) compositor
+install : $(libs)
 	install -d $(libdir) $(includedir) $(libdir)/pkgconfig
 	install wayland-server.pc wayland-client.pc $(libdir)/pkgconfig
 	install $(libs) $(libdir)

wayland/protocol.xml

@@ -213,6 +213,7 @@
 
   <interface name="input_device" version="1">
     <request name="attach">
+      <arg name="time" type="uint"/>
       <arg name="buffer" type="object" interface="buffer"/>
       <arg name="hotspot_x" type="int"/>
       <arg name="hotspot_y" type="int"/>