+ win->_curx = 0;
+ return (OK);
+}
+
+#if USE_WIDEC_SUPPORT
+static int waddch_literal(WINDOW *, NCURSES_CH_T);
+/*
+ * Fill the given number of cells with blanks using the current background
+ * rendition. This saves/restores the current x-position.
+ */
+static void
+fill_cells(WINDOW *win, int count)
+{
+ NCURSES_CH_T blank = blankchar;
+ int save_x = win->_curx;
+ int save_y = win->_cury;
+
+ while (count-- > 0) {
+ if (waddch_literal(win, blank) == ERR)
+ break;
+ }
+ win->_curx = (NCURSES_SIZE_T) save_x;
+ win->_cury = (NCURSES_SIZE_T) save_y;
+}
+#endif
+
+/*
+ * Build up the bytes for a multibyte character, returning the length when
+ * complete (a positive number), -1 for error and -2 for incomplete.
+ */
+#if USE_WIDEC_SUPPORT
+NCURSES_EXPORT(int)
+_nc_build_wch(WINDOW *win, ARG_CH_T ch)
+{
+ char *buffer = WINDOW_EXT(win, addch_work);
+ int len;
+ int x = win->_curx;
+ int y = win->_cury;
+ mbstate_t state;
+ wchar_t result;
+
+ if ((WINDOW_EXT(win, addch_used) != 0) &&
+ (WINDOW_EXT(win, addch_x) != x ||
+ WINDOW_EXT(win, addch_y) != y)) {
+ /* discard the incomplete multibyte character */
+ WINDOW_EXT(win, addch_used) = 0;
+ TR(TRACE_VIRTPUT,
+ ("Alert discarded multibyte on move (%d,%d) -> (%d,%d)",
+ WINDOW_EXT(win, addch_y), WINDOW_EXT(win, addch_x),
+ y, x));
+ }
+ WINDOW_EXT(win, addch_x) = x;
+ WINDOW_EXT(win, addch_y) = y;
+
+ init_mb(state);
+ buffer[WINDOW_EXT(win, addch_used)] = (char) CharOf(CHDEREF(ch));
+ WINDOW_EXT(win, addch_used) += 1;
+ buffer[WINDOW_EXT(win, addch_used)] = '\0';
+ if ((len = (int) mbrtowc(&result,
+ buffer,
+ (size_t) WINDOW_EXT(win, addch_used),
+ &state)) > 0) {
+ attr_t attrs = AttrOf(CHDEREF(ch));
+ if_EXT_COLORS(int pair = GetPair(CHDEREF(ch)));
+ SetChar(CHDEREF(ch), result, attrs);
+ if_EXT_COLORS(SetPair(CHDEREF(ch), pair));
+ WINDOW_EXT(win, addch_used) = 0;
+ } else if (len == -1) {
+ /*
+ * An error occurred. We could either discard everything,
+ * or assume that the error was in the previous input.
+ * Try the latter.
+ */
+ TR(TRACE_VIRTPUT, ("Alert! mbrtowc returns error"));
+ /* handle this with unctrl() */
+ WINDOW_EXT(win, addch_used) = 0;
+ }
+ return len;
+}
+#endif /* USE_WIDEC_SUPPORT */
+
+static
+#if !USE_WIDEC_SUPPORT /* cannot be inline if it is recursive */
+NCURSES_INLINE