1 /* $NetBSD: list.c,v 1.10 2021/05/02 12:50:43 rillig Exp $ */
2
3 /*-
4 * Copyright (c) 1990, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Ed James.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 /*
36 * Copyright (c) 1987 by Ed James, UC Berkeley. All rights reserved.
37 *
38 * Copy permission is hereby granted provided that this notice is
39 * retained on all partial or complete copies.
40 *
41 * For more info on this and all of my stuff, mail edjames@berkeley.edu.
42 */
43
44 #include <sys/cdefs.h>
45 #ifndef lint
46 #if 0
47 static char sccsid[] = "@(#)list.c 8.1 (Berkeley) 5/31/93";
48 #else
49 __RCSID("$NetBSD: list.c,v 1.10 2021/05/02 12:50:43 rillig Exp $");
50 #endif
51 #endif /* not lint */
52
53 #include <stdlib.h>
54
55 #include "def.h"
56 #include "struct.h"
57 #include "extern.h"
58 #include "tunable.h"
59
60 PLANE *
newplane(void)61 newplane(void)
62 {
63 return calloc(1, sizeof (PLANE));
64 }
65
66 void
append(LIST * l,PLANE * p)67 append(LIST *l, PLANE *p)
68 {
69 PLANE *q = NULL, *r = NULL;
70
71 if (l->head == NULL) {
72 p->next = p->prev = NULL;
73 l->head = l->tail = p;
74 } else {
75 q = l -> head;
76
77 while (q != NULL && q->plane_no < p->plane_no) {
78 r = q;
79 q = q -> next;
80 }
81
82 if (q) {
83 if (r) {
84 p->prev = r;
85 r->next = p;
86 p->next = q;
87 q->prev = p;
88 } else {
89 p->next = q;
90 p->prev = NULL;
91 q->prev = p;
92 l->head = p;
93 }
94 } else {
95 l->tail->next = p;
96 p->next = NULL;
97 p->prev = l->tail;
98 l->tail = p;
99 }
100 }
101 }
102
103 void
delete(LIST * l,PLANE * p)104 delete(LIST *l, PLANE *p)
105 {
106 if (l->head == NULL)
107 loser(p, "deleted a non-existent plane! Get help!");
108
109 if (l->head == p && l->tail == p)
110 l->head = l->tail = NULL;
111 else if (l->head == p) {
112 l->head = p->next;
113 l->head->prev = NULL;
114 } else if (l->tail == p) {
115 l->tail = p->prev;
116 l->tail->next = NULL;
117 } else {
118 p->prev->next = p->next;
119 p->next->prev = p->prev;
120 }
121 }
122