root/lib/libcurses/copywin.c
/*      $NetBSD: copywin.c,v 1.22 2024/12/23 02:58:03 blymn Exp $       */

/*-
 * Copyright (c) 1998-1999 Brett Lymn
 *                         (blymn@baea.com.au, brett_lymn@yahoo.com.au)
 * All rights reserved.
 *
 * This code has been donated to The NetBSD Foundation by the Author.
 *
 * 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. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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
__RCSID("$NetBSD: copywin.c,v 1.22 2024/12/23 02:58:03 blymn Exp $");
#endif                          /* not lint */

#include <ctype.h>
#include <string.h>
#include "curses.h"
#include "curses_private.h"

/*
 * copywin --
 *     Copy the box starting at (sminrow, smincol) with a size that
 *     matches the destination box (dminrow, dmincol) by (dmaxrow, dmaxcol)
 *     from the source window srcwin to the destination window dstwin.
 *     All these coordindinates are relative to the relevant window.
 *     If dooverlay is true then the copy is nondestructive otherwise the
 *     copy is destructive.
 */
int copywin(const WINDOW *srcwin, WINDOW *dstwin,
            int sminrow, int smincol,
            int dminrow, int dmincol, int dmaxrow, int dmaxcol, int dooverlay)
{
        int dcol;
        __LDATA *sp, *end;
#ifdef HAVE_WCHAR
        cchar_t cc;
        nschar_t *np;
#endif /* HAVE_WCHAR */

        __CTRACE(__CTRACE_WINDOW,
            "copywin %s mode: from (%d,%d) to (%d,%d-%d,%d)\n",
            dooverlay ? "overlay" : "overwrite",
            sminrow, smincol, dminrow, dmincol, dmaxrow, dmaxcol);

        if ((srcwin == NULL) || (dstwin == NULL))
                return ERR;

        /* overwrite() and overlay() can come here with -ve srcwin coords */
        if (sminrow < 0) {
                dminrow -= sminrow;
                sminrow = 0;
        }
        if (smincol < 0) {
                dmincol -= smincol;
                smincol = 0;
        }

        /* for symmetry allow dstwin coords to be -ve as well */
        if (dminrow < 0) {
                sminrow -= dminrow;
                dminrow = 0;
        }
        if (dmincol < 0) {
                smincol -= dmincol;
                dmincol = 0;
        }

        /* Bound dmaxcol for both windows (should be ok for dstwin) */
        if (dmaxcol >= dstwin->maxx)
                dmaxcol = dstwin->maxx - 1;
        if (smincol + (dmaxcol - dmincol) >= srcwin->maxx)
                dmaxcol = srcwin->maxx + dmincol - smincol - 1;
        if (dmaxcol < dmincol)
                /* nothing in the intersection */
                return OK;

        /* Bound dmaxrow for both windows (should be ok for dstwin) */
        if (dmaxrow >= dstwin->maxy)
                dmaxrow = dstwin->maxy - 1;
        if (sminrow + (dmaxrow - dminrow) >= srcwin->maxy)
                dmaxrow = srcwin->maxy + dminrow - sminrow - 1;

        __CTRACE(__CTRACE_WINDOW,
            "copywin %s mode: from (%d,%d) to (%d,%d-%d,%d)\n",
            dooverlay ? "overlay" : "overwrite",
            sminrow, smincol, dminrow, dmincol, dmaxrow, dmaxcol);

        for (; dminrow <= dmaxrow; sminrow++, dminrow++) {
                sp = &srcwin->alines[sminrow]->line[smincol];
                end = sp + dmaxcol - dmincol;
        __CTRACE(__CTRACE_WINDOW, "copywin: row %d\n", sminrow);
                for (dcol = dmincol; sp <= end; dcol++, sp++) {
                        /* XXX: Perhaps this should check for the
                         * background character
                         */
                        if ((dooverlay && !isspace(sp->ch)) || !dooverlay) {
                                wmove(dstwin, dminrow, dcol);
        __CTRACE(__CTRACE_WINDOW, "copywin: dcol = %d\n", dcol);
#ifndef HAVE_WCHAR
                                __waddch(dstwin, sp);
#else
                                cc.vals[0] = sp->ch;
                                cc.attributes = sp->attr;
                                cc.elements = 1;
                                np = sp->nsp;
                                if (np) {
                                        while (np && cc.elements <=
                                            CURSES_CCHAR_MAX) {
                                                cc.vals[cc.elements++] = np->ch;
                                                np = np->next;
                                        }
                                }
                                wadd_wch(dstwin, &cc);
#endif /* HAVE_WCHAR */
                        }
                }
        }
        __touchwin(dstwin, 0);
        return OK;
}