skin_engine: kill scrolling if the buffer moves

I have a suspicion that if there is any scrolling skin lines when
the buflib buffer moves it will cause the lcd code to crash.

This *hopefully* explains the random skin related crashed which
have been reported.

Change-Id: I04ee58292e1cea7c77ef9737b0641192f4f7e4ba
Reviewed-on: http://gerrit.rockbox.org/877
Reviewed-by: Thomas Martitz <kugel@rockbox.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/apps/gui/skin_engine/skin_parser.c b/apps/gui/skin_engine/skin_parser.c
index c659e70730..0e7150c553 100644
--- a/apps/gui/skin_engine/skin_parser.c
+++ b/apps/gui/skin_engine/skin_parser.c
@@ -1752,6 +1752,16 @@ static int buflib_move_callback(int handle, void* current, void* new)
     (void)new;
     if (handle == currently_loading_handle)
         return BUFLIB_CB_CANNOT_MOVE;
+    /* Any active skins may be scrolling - which means using viewports which
+     * will be moved after this callback returns. This is a hammer to make that
+     * safe. TODO: use a screwdriver instead.
+     */
+    FOR_NB_SCREENS(i)
+        screens[i].scroll_stop();
+
+    for (int i = 0; i < SKINNABLE_SCREENS_COUNT; i++)
+        skin_request_full_update(i);
+
     return BUFLIB_CB_OK;
 }
 static struct buflib_callbacks buflib_ops = {buflib_move_callback, NULL, NULL};