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diff --git a/contrib/ncurses/ncurses/base/lib_scroll.c b/contrib/ncurses/ncurses/base/lib_scroll.c
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+/****************************************************************************
+ * Copyright (c) 1998 Free Software Foundation, Inc. *
+ * *
+ * Permission is hereby granted, free of charge, to any person obtaining a *
+ * copy of this software and associated documentation files (the *
+ * "Software"), to deal in the Software without restriction, including *
+ * without limitation the rights to use, copy, modify, merge, publish, *
+ * distribute, distribute with modifications, sublicense, and/or sell *
+ * copies of the Software, and to permit persons to whom the Software is *
+ * furnished to do so, subject to the following conditions: *
+ * *
+ * The above copyright notice and this permission notice shall be included *
+ * in all copies or substantial portions of the Software. *
+ * *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
+ * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
+ * THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
+ * *
+ * Except as contained in this notice, the name(s) of the above copyright *
+ * holders shall not be used in advertising or otherwise to promote the *
+ * sale, use or other dealings in this Software without prior written *
+ * authorization. *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995 *
+ * and: Eric S. Raymond <esr@snark.thyrsus.com> *
+ ****************************************************************************/
+
+
+
+/*
+** lib_scroll.c
+**
+** The routine wscrl(win, n).
+** positive n scroll the window up (ie. move lines down)
+** negative n scroll the window down (ie. move lines up)
+**
+*/
+
+#include <curses.priv.h>
+
+MODULE_ID("$Id: lib_scroll.c,v 1.16 1998/02/11 12:13:55 tom Exp $")
+
+void _nc_scroll_window(WINDOW *win, int const n, short const top, short const bottom, chtype blank)
+{
+int line, j;
+size_t to_copy = (size_t)(sizeof(chtype) * (win->_maxx + 1));
+
+ TR(TRACE_MOVE, ("_nc_scroll_window(%p, %d, %d, %d)", win, n, top,bottom));
+
+ /*
+ * This used to do a line-text pointer-shuffle instead of text copies.
+ * That (a) doesn't work when the window is derived and doesn't have
+ * its own storage, (b) doesn't save you a lot on modern machines
+ * anyway. Your typical memcpy implementations are coded in
+ * assembler using a tight BLT loop; for the size of copies we're
+ * talking here, the total execution time is dominated by the one-time
+ * setup cost. So there is no point in trying to be excessively
+ * clever -- esr.
+ */
+
+ /* shift n lines downwards */
+ if (n < 0) {
+ for (line = bottom; line >= top-n; line--) {
+ memcpy(win->_line[line].text,
+ win->_line[line+n].text,
+ to_copy);
+ if_USE_SCROLL_HINTS(win->_line[line].oldindex = win->_line[line+n].oldindex);
+ }
+ for (line = top; line < top-n; line++) {
+ for (j = 0; j <= win->_maxx; j ++)
+ win->_line[line].text[j] = blank;
+ if_USE_SCROLL_HINTS(win->_line[line].oldindex = _NEWINDEX);
+ }
+ }
+
+ /* shift n lines upwards */
+ if (n > 0) {
+ for (line = top; line <= bottom-n; line++) {
+ memcpy(win->_line[line].text,
+ win->_line[line+n].text,
+ to_copy);
+ if_USE_SCROLL_HINTS(win->_line[line].oldindex = win->_line[line+n].oldindex);
+ }
+ for (line = bottom; line > bottom-n; line--) {
+ for (j = 0; j <= win->_maxx; j ++)
+ win->_line[line].text[j] = blank;
+ if_USE_SCROLL_HINTS(win->_line[line].oldindex = _NEWINDEX);
+ }
+ }
+ touchline(win, top, bottom-top+1);
+}
+
+int
+wscrl(WINDOW *win, int n)
+{
+ T((T_CALLED("wscrl(%p,%d)"), win, n));
+
+ if (!win || !win->_scroll)
+ returnCode(ERR);
+
+ if (n == 0)
+ returnCode(OK);
+
+ if ((n > (win->_regbottom - win->_regtop)) ||
+ (-n > (win->_regbottom - win->_regtop)))
+ returnCode(ERR);
+
+ _nc_scroll_window(win, n, win->_regtop, win->_regbottom, _nc_background(win));
+
+ _nc_synchook(win);
+ returnCode(OK);
+}