usr/src/lib/libcurses/screen/derwin.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 #include        <sys/types.h>
  45 #include        "curses_inc.h"
  46
  47 /*
  48  *      Make a  derived window of an existing window. The two windows
  49  *      share the same character image.
  50  *              orig:   the original window
  51  *              nl, nc: numbers of lines and columns
  52  *              by, bx: coordinates for upper-left corner of the derived
  53  *                      window in the coord system of the parent window.
  54  */
  55
  56 WINDOW  *
  57 derwin(WINDOW *orig, int num_lines, int nc, int by, int bx)
  58 {
  59         int     y;
  60         WINDOW  *win = (WINDOW *) NULL, *par;
  61         chtype  **w_y, **o_y;
  62 #ifdef  _VR3_COMPAT_CODE
  63         _ochtype        **w_y16, **o_y16;
  64 #endif  /* _VR3_COMPAT_CODE */
  65
  66         /* make sure window fits inside the original one */
  67         if (by < 0 || (by + num_lines) > orig->_maxy || bx < 0 ||
  68             (bx + nc) > orig->_maxx)
  69                 goto done;
  70         if (nc == 0)
  71                 nc = orig->_maxx - bx;
  72         if (num_lines == 0)
  73                 num_lines = orig->_maxy - by;
  74
  75         /* Create the window skeleton */
  76         if ((win = _makenew(num_lines, nc, by + orig->_begy,
  77             bx + orig->_begx)) == NULL)
  78                 goto done;
  79
  80         /* inheritance */
  81         /*LINTED*/
  82         win->_parx = (short) bx;
  83         /*LINTED*/
  84         win->_pary = (short) by;
  85         win->_bkgd = orig->_bkgd;
  86         win->_attrs = orig->_attrs;
  87         w_y = win->_y;
  88         o_y = orig->_y;
  89
  90 #ifdef  _VR3_COMPAT_CODE
  91         if (_y16update) {
  92                 int     hby = by;
  93
  94                 w_y16 = win ->_y16;
  95                 o_y16 = orig->_y16;
  96
  97                 for (y = 0; y < num_lines; y++, hby++)
  98                         w_y16[y] = o_y16[hby] + bx;
  99         }
 100 #endif  /* _VR3_COMPAT_CODE */
 101
 102         for (y = 0; y < num_lines; y++, by++)
 103                 w_y[y] = o_y[by] + bx;
 104
 105         win->_yoffset = orig->_yoffset;
 106
 107         /* update descendant number of ancestors */
 108         win->_parent = orig;
 109         for (par = win->_parent; par != NULL; par = par->_parent)
 110                 par->_ndescs += 1;
 111
 112 done:
 113         return (win);
 114 }