libcurses/screen/mbinsshift.c

	mbinsshift.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*  Copyright (c) 1988 AT&T */
/*    All Rights Reserved   */


/*
 *      Copyright (c) 1997, by Sun Microsystems, Inc.
 *      All rights reserved.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

/*LINTLIBRARY*/

#include    <sys/types.h>
#include    "curses_inc.h"

/*
 *  Shift right an interval of characters
 */

int
_mbinsshift(WINDOW *win, int len)
{
    int x, y, maxx,  mv;
    chtype  *wcp, *wp, *ep;

    y = win->_cury;
    x = win->_curx;
    maxx = win->_maxx;
    wcp  = win->_y[y];

    /* ASSERT(!ISCBIT(wcp[x])); */

    /* shift up to a whole character */
    if (_scrmax > 1) {
        wp = wcp + maxx - 1;
        if (ISMBIT(*wp)) {
            reg chtype  rb;

            for (; wp >= wcp; --wp)
                if (!ISCBIT(*wp))
                    break;
            if (wp < wcp)
                return (ERR);
            rb = RBYTE(*wp);
            if ((wp + _curs_scrwidth[TYPE(rb)]) > (wcp + maxx))
                /*LINTED*/
                maxx = (int)(wp - wcp);
            }
        }

    /* see if any data need to move */
    if ((mv = maxx - (x+len)) <= 0)
        return (OK);

    /* the end of the moved interval must be whole */
    if (ISCBIT(wcp[x + mv]))
        (void) _mbclrch(win, y, x + mv - 1);

    /* move data */
    ep = wcp + x + len;
    for (wp = wcp + maxx - 1; wp >= ep; --wp)
        *wp = *(wp - len);

    /* clear a possible partial multibyte character */
    if (ISMBIT(*wp))
        for (ep = wp; ep >= wcp; --ep) {
            mv = (int)(ISCBIT(*ep));
            *ep = win->_bkgd;
            if (!mv)
                break;
        }

    /* update the change structure */
    if (x < win->_firstch[y])
        /*LINTED*/
        win->_firstch[y] = (short)x;
    win->_lastch[y] = maxx - 1;

    return (OK);
}