/*      $NetBSD: erase.c,v 1.38 2024/12/23 02:58:03 blymn Exp $ */

/*
* Copyright (c) 1981, 1993, 1994
*      The Regents of the University of California.  All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)erase.c     8.2 (Berkeley) 5/4/94";
#else
__RCSID("$NetBSD: erase.c,v 1.38 2024/12/23 02:58:03 blymn Exp $");
#endif
#endif                          /* not lint */

#include <stdlib.h>

#include "curses.h"
#include "curses_private.h"

#ifndef _CURSES_USE_MACROS

/*
* erase --
*      Erases everything on stdscr.
*/
int
erase(void)
{
       return werase(stdscr);
}

#endif

/*
* werase --
*      Erases everything on the window.
*/
int
werase(WINDOW *win)
{
       int     y;
       __LDATA *sp, *end, *start;
       wchar_t bch;
       attr_t  battr;

       __CTRACE(__CTRACE_ERASE, "werase: (%p)\n", win);

       if (__predict_false(win == NULL))
               return ERR;

       bch = win->bch;
       if (win != curscr)
               battr = win->battr & __ATTRIBUTES;
       else
               battr = 0;

       for (y = 0; y < win->maxy; y++) {
               start = win->alines[y]->line;
               end = &start[win->maxx];
               for (sp = start; sp < end; sp++) {
                       if (!(__NEED_ERASE(sp, bch, battr)))
                               continue;

                       sp->ch = bch;
                       sp->cflags |= CA_BACKGROUND;
                       sp->cflags &= ~CA_CONTINUATION;
                       sp->attr = battr | (sp->attr & __ALTCHARSET);
#ifdef HAVE_WCHAR
                       if (_cursesi_copy_nsp(win->bnsp, sp) == ERR)
                               return ERR;
                       sp->wcols = 1;
#endif
               }
       }

       /*
        * Mark the whole window as changed in case we have overlapping
        * windows - this will result in the (intended) clearing of the
        * screen over the area covered by the window. */
       __touchwin(win, 0);
       wmove(win, 0, 0);
       return OK;
}