usr/src/lib/libcurses/screen/wredrawln.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*      Copyright (c) 1988 AT&T */
  28 /*        All Rights Reserved   */
  29
  30 /*
  31  * University Copyright- Copyright (c) 1982, 1986, 1988
  32  * The Regents of the University of California
  33  * All Rights Reserved
  34  *
  35  * University Acknowledgment- Portions of this document are derived from
  36  * software developed by the University of California, Berkeley, and its
  37  * contributors.
  38  */
  39
  40 #pragma ident   "%Z%%M% %I%     %E% SMI"
  41
  42 /*LINTLIBRARY*/
  43
  44 /*
  45  * This routine indicates to curses that a screen line is garbaged and
  46  * should be thrown away before having anything written over the top of it.
  47  * It could be used for programs such as editors which want a command to
  48  * redraw just a single line. Such a command could be used in cases where
  49  * there is a noisy line and redrawing the entire screen would be subject
  50  * to even more noise. Just redrawing the single line gives some semblance
  51  * of hope that it would show up unblemished.
  52  *
  53  * This is a more refined version of clearok
  54  */
  55
  56 #include        <sys/types.h>
  57 #include        "curses_inc.h"
  58
  59 int
  60 wredrawln(WINDOW *win, int begline, int numlines)
  61 {
  62         short   *firstch, *efirstch;
  63
  64         if (numlines <= 0)
  65                 return (ERR);
  66         if (begline < 0)
  67                 begline = 0;
  68         if (begline + numlines > win->_maxy)
  69                 numlines = win->_maxy - begline;
  70
  71         firstch = win->_firstch + begline;
  72         efirstch = firstch + numlines;
  73         while (firstch < efirstch)
  74                 *firstch++ = _REDRAW;
  75
  76         return (win->_immed ? wrefresh(win) : OK);
  77 }