1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
/* $OpenBSD: lstRequeue.c,v 1.1 2008/01/12 13:05:57 espie Exp $ */
/*
* Copyright (c) 2008 Marc Espie.
*
* 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. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT AND CONTRIBUTORS
* ``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 OPENBSD
* PROJECT OR CONTRIBUTORS 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 "lstInt.h"
#include <stdlib.h>
/* Lst_Requeue(l, ln): takes node ln from the list and requeue it at front.
*/
void
Lst_Requeue(Lst l, LstNode ln)
{
/* already at front */
if (l->firstPtr == ln)
return;
/* unlink element */
if (ln->nextPtr != NULL)
ln->nextPtr->prevPtr = ln->prevPtr;
if (ln->prevPtr != NULL)
ln->prevPtr->nextPtr = ln->nextPtr;
if (l->lastPtr == ln)
l->lastPtr = ln->prevPtr;
/* relink at front */
ln->nextPtr = l->firstPtr;
ln->prevPtr = NULL;
l->firstPtr->prevPtr = ln;
l->firstPtr = ln;
}
|
