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erase.c revision 1.31 
      1 /*	$NetBSD: erase.c,v 1.31 2020/03/13 02:57:26 roy Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1981, 1993, 1994
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 #ifndef lint
     34 #if 0
     35 static char sccsid[] = "@(#)erase.c	8.2 (Berkeley) 5/4/94";
     36 #else
     37 __RCSID("$NetBSD: erase.c,v 1.31 2020/03/13 02:57:26 roy Exp $");
     38 #endif
     39 #endif				/* not lint */
     40 
     41 #include <stdlib.h>
     42 
     43 #include "curses.h"
     44 #include "curses_private.h"
     45 
     46 #ifndef _CURSES_USE_MACROS
     47 
     48 /*
     49  * erase --
     50  *	Erases everything on stdscr.
     51  */
     52 int
     53 erase(void)
     54 {
     55 	return werase(stdscr);
     56 }
     57 
     58 #endif
     59 
     60 /*
     61  * werase --
     62  *	Erases everything on the window.
     63  */
     64 int
     65 werase(WINDOW *win)
     66 {
     67 	int     y;
     68 	__LDATA *sp, *end, *start;
     69 	wchar_t	bch;
     70 	attr_t	attr;
     71 
     72 #ifdef DEBUG
     73 	__CTRACE(__CTRACE_ERASE, "werase: (%p)\n", win);
     74 #endif
     75 #ifdef HAVE_WCHAR
     76 	bch = (wchar_t)btowc((int)win->bch);
     77 #else
     78 	bch = win->bch;
     79 #endif
     80 	if (win != curscr)
     81 		attr = win->battr & __ATTRIBUTES;
     82 	else
     83 		attr = 0;
     84 
     85 	for (y = 0; y < win->maxy; y++) {
     86 		start = win->alines[y]->line;
     87 		end = &start[win->maxx];
     88 		for (sp = start; sp < end; sp++) {
     89 			if (!(__NEED_ERASE(sp, bch, attr)))
     90 				continue;
     91 			sp->attr = attr | (sp->attr & __ALTCHARSET);
     92 			sp->ch = bch;
     93 #ifdef HAVE_WCHAR
     94 			if (_cursesi_copy_nsp(win->bnsp, sp) == ERR)
     95 				return ERR;
     96 			SET_WCOL(*sp, 1);
     97 #endif
     98 		}
     99 	}
    100 
    101 	/*
    102 	 * Mark the whole window as changed in case we have overlapping
    103 	 * windows - this will result in the (intended) clearing of the
    104 	 * screen over the area covered by the window. */
    105 	__touchwin(win);
    106 	wmove(win, 0, 0);
    107 	return OK;
    108 }
    109