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
40 static 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
47 static 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 */
56 int
__m_ptr_move(void ** array,unsigned int length,unsigned int start,unsigned int finish,unsigned int to)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 */
81 static void
reverse(void ** ptr,unsigned int a,unsigned int b)82 reverse(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