drm_linux_list_sort.c revision 331722 
1/*
2 * Copyright (c) 2011 The FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by Konstantin Belousov under sponsorship from
6 * the FreeBSD Foundation.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <dev/drm2/drmP.h>
31__FBSDID("$FreeBSD: stable/11/sys/dev/drm2/drm_linux_list_sort.c 331722 2018-03-29 02:50:57Z eadler $");
32
33struct drm_list_sort_thunk {
34	int (*cmp)(void *, struct list_head *, struct list_head *);
35	void *priv;
36};
37
38static int
39drm_le_cmp(void *priv, const void *d1, const void *d2)
40{
41	struct list_head *le1, *le2;
42	struct drm_list_sort_thunk *thunk;
43
44	thunk = priv;
45	le1 = *(__DECONST(struct list_head **, d1));
46	le2 = *(__DECONST(struct list_head **, d2));
47	return ((thunk->cmp)(thunk->priv, le1, le2));
48}
49
50/*
51 * Punt and use array sort.
52 */
53void
54drm_list_sort(void *priv, struct list_head *head, int (*cmp)(void *priv,
55    struct list_head *a, struct list_head *b))
56{
57	struct drm_list_sort_thunk thunk;
58	struct list_head **ar, *le;
59	int count, i;
60
61	count = 0;
62	list_for_each(le, head)
63		count++;
64	ar = malloc(sizeof(struct list_head *) * count, M_TEMP, M_WAITOK);
65	i = 0;
66	list_for_each(le, head)
67		ar[i++] = le;
68	thunk.cmp = cmp;
69	thunk.priv = priv;
70	qsort_r(ar, count, sizeof(struct list_head *), &thunk, drm_le_cmp);
71	INIT_LIST_HEAD(head);
72	for (i = 0; i < count; i++)
73		list_add_tail(ar[i], head);
74	free(ar, M_TEMP);
75}
76