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 (c) 1995-1998 by Sun Microsystems, Inc.
24 * All rights reserved.
25 */
26
27#pragma ident	"%Z%%M%	%I%	%E% SMI"
28
29/* LINTLIBRARY */
30
31/*
32 * ptrmove.c
33 *
34 * Copyright 1990, 1995 by Mortice Kern Systems Inc.  All rights reserved.
35 *
36 */
37
38#ifdef M_RCSID
39#ifndef lint
40static char rcsID[] = "$Header: /rd/src/libc/xcurses/rcs/ptrmove.c 1.3 "
41"1995/05/18 20:55:05 ant Exp $";
42#endif
43#endif
44
45#include <private.h>
46
47static void	reverse(void **, unsigned int, unsigned int);
48
49/*
50 * Move range start..finish inclusive before the given location.
51 * Return -1 if the region to move is out of bounds or the target
52 * falls within the region; 0 for success.
53 *
54 * (See Software Tools chapter 6.)
55 */
56int
57__m_ptr_move(void **array, unsigned int length,
58	unsigned int start, unsigned int finish, unsigned int to)
59{
60	if (finish < start || length <= finish)
61		return (-1);
62
63	if (to < start) {
64		reverse(array, to, start-1);
65		reverse(array, start, finish);
66		reverse(array, to, finish);
67	} else if (finish < to && to <= length) {
68		reverse(array, start, finish);
69		reverse(array, finish+1, to-1);
70		reverse(array, start, to-1);
71	} else {
72		return (-1);
73	}
74
75	return (0);
76}
77
78/*
79 * Reverse range a..b inclusive.
80 */
81static void
82reverse(void **ptr, unsigned int a, unsigned int b)
83{
84	void	*temp;
85	void	**a_ptr = &ptr[a];
86	void	**b_ptr = &ptr[b];
87
88	while (a_ptr < b_ptr) {
89		temp = *a_ptr;
90		*a_ptr++ = *b_ptr;
91		*b_ptr-- = temp;
92	}
93}
94