server: Don't allow orphaned windows in set_parent request.

dlls/user32/tests/win.c

@@ -865,16 +865,13 @@ static void test_thread_exit_destroy(void)
     SetLastError( 0xdeadbeef );
     tmp = SetParent( child1, adopter );
     ok( tmp == 0, "SetParent returned %p\n", tmp );
-    todo_wine
     ok( GetLastError() == ERROR_INVALID_PARAMETER, "got error %u\n", GetLastError() );
     SetLastError( 0xdeadbeef );
     tmp = SetParent( child3, adopter );
     ok( tmp == 0, "SetParent returned %p\n", tmp );
-    todo_wine
     ok( GetLastError() == ERROR_INVALID_PARAMETER, "got error %u\n", GetLastError() );
     SetLastError( 0xdeadbeef );
     tmp = GetParent( child1 );
-    todo_wine
     ok( tmp == params.hwnd, "GetParent returned %p, error %u\n", tmp, GetLastError() );
     ok( GetLastError() == 0xdeadbeef, "GetWindowLongW error %u\n", GetLastError() );
 

dlls/user32/win.c

@@ -3374,7 +3374,7 @@ HWND WINAPI SetParent( HWND hwnd, HWND parent )
     {
         req->handle = wine_server_user_handle( hwnd );
         req->parent = wine_server_user_handle( parent );
-        if ((ret = !wine_server_call( req )))
+        if ((ret = !wine_server_call_err( req )))
         {
             old_parent = wine_server_ptr_handle( reply->old_parent );
             wndPtr->parent = parent = wine_server_ptr_handle( reply->full_parent );

server/window.c

@@ -200,6 +200,14 @@ static inline int is_desktop_window( const struct window *win )
     return !win->parent;  /* only desktop windows have no parent */
 }
 
+/* check if window is orphaned */
+static int is_orphan_window( struct window *win )
+{
+    do if (!win->handle) return 1;
+    while ((win = win->parent));
+    return 0;
+}
+
 /* get next window in Z-order list */
 static inline struct window *get_next_window( struct window *win )
 {
@@ -2066,7 +2074,7 @@ DECL_HANDLER(set_parent)
     if (!(win = get_window( req->handle ))) return;
     if (req->parent && !(parent = get_window( req->parent ))) return;
 
-    if (is_desktop_window(win))
+    if (is_desktop_window(win) || is_orphan_window( win ) || (parent && is_orphan_window( parent )))
     {
         set_error( STATUS_INVALID_PARAMETER );
         return;