Removed older regexp function for new POSIX regex handling due to
[unix-history] / lib / libc / gen / insque.c
CommitLineData
ea4df996
AM
1/*
2 * Copyright (c) 1993 John Brezak
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. The name of the author may be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
20 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
24 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
25 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#if defined(LIBC_SCCS) && !defined(lint)
30static char rcsid[] = "$Id: insque.c,v 1.2 1993/08/13 12:54:10 brezak Exp $";
31#endif /* LIBC_SCCS and not lint */
32
33struct qelem {
34 struct qelem *q_forw;
35 struct qelem *q_back;
36 char *q_data;
37};
38
39/*
40 * Link p before s.
41 */
42#define reque(p, s) (p)->q_forw = (s), (s)->q_back = (p)
43
44/*
45 * Insert entry in circular queue after pred.
46 */
47struct qelem *
48insque(entry, pred)
49 struct qelem *entry, *pred;
50{
51 reque(entry, pred->q_forw);
52 reque(pred, entry);
53 return (entry);
54}
55
56/*
57 * Remove entry from circular queue.
58 */
59struct qelem *
60remque(entry)
61 struct qelem *entry;
62{
63 reque(entry->q_back, entry->q_forw);
64 return (entry);
65}