xref: /src/lib/libcurses/clrtoeol.c

/*	$NetBSD: clrtoeol.c,v 1.35.4.1 2025/08/02 05:54:45 perseant 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[] = "@(#)clrtoeol.c	8.2 (Berkeley) 5/4/94";
#else
__RCSID("$NetBSD: clrtoeol.c,v 1.35.4.1 2025/08/02 05:54:45 perseant Exp $");
#endif
#endif				/* not lint */

#include <stdlib.h>
#include "curses.h"
#include "curses_private.h"

#ifndef _CURSES_USE_MACROS

/*
 * clrtoeol --
 *	Clear up to the end of line.
 */
int
clrtoeol(void)
{
	return wclrtoeol(stdscr);
}

#endif

/*
 * wclrtoeol --
 *	Clear up to the end of line.
 */
int
wclrtoeol(WINDOW *win)
{
	int     minx, x, y;
	__LDATA *end, *maxx, *sp;
	wchar_t bch;
	attr_t	battr;

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

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

	y = win->cury;
	x = win->curx;
	if (win->alines[y]->flags & __ISPASTEOL) {
		if (y < win->maxy - 1) {
			win->alines[y]->flags &= ~__ISPASTEOL;
			y++;
			x = 0;
			win->cury = y;
			win->curx = x;
		} else
			return OK;
	}
	end = &win->alines[y]->line[win->maxx];
	minx = -1;
	maxx = &win->alines[y]->line[x];

	for (sp = maxx; sp < end; sp++) {
		/*
		 * It looks like ncurses makes the rest of line foreground
		 * when it is cleared - this doesn't seem right but it
		 * makes applicatins look right.
		 */
		sp->cflags &= ~CA_BACKGROUND;
		if (!(__NEED_ERASE(sp, bch, battr)))
			continue;

		maxx = sp;
		if (minx == -1)
			minx = (int)(sp - win->alines[y]->line);

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

	__CTRACE(__CTRACE_ERASE, "CLRTOEOL: y = %d, minx = %d, maxx = %d, "
	    "firstch = %d, lastch = %d\n",
	    y, minx, (int)(maxx - win->alines[y]->line),
	    *win->alines[y]->firstchp, *win->alines[y]->lastchp);
	/* Update firstch and lastch for the line. */
	__touchline(win, y, x, (int)win->maxx - 1);
	__sync(win);
	return OK;
}