1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Ed James. 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 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)list.c 8.1 (Berkeley) 5/31/93 37 * $FreeBSD: src/games/atc/list.c,v 1.4 1999/11/30 03:48:20 billf Exp $ 38 * $DragonFly: src/games/atc/list.c,v 1.2 2003/06/17 04:25:22 dillon Exp $ 39 */ 40 41 /* 42 * Copyright (c) 1987 by Ed James, UC Berkeley. All rights reserved. 43 * 44 * Copy permission is hereby granted provided that this notice is 45 * retained on all partial or complete copies. 46 * 47 * For more info on this and all of my stuff, mail edjames@berkeley.edu. 48 */ 49 50 #include <stdlib.h> 51 #include "include.h" 52 53 PLANE * 54 newplane() 55 { 56 return ((PLANE *) calloc(1, sizeof (PLANE))); 57 } 58 59 append(l, p) 60 LIST *l; 61 PLANE *p; 62 { 63 PLANE *q = NULL, *r = NULL; 64 65 if (l->head == NULL) { 66 p->next = p->prev = NULL; 67 l->head = l->tail = p; 68 } else { 69 q = l -> head; 70 71 while (q != NULL && q->plane_no < p->plane_no) { 72 r = q; 73 q = q -> next; 74 } 75 76 if (q) { 77 if (r) { 78 p->prev = r; 79 r->next = p; 80 p->next = q; 81 q->prev = p; 82 } else { 83 p->next = q; 84 p->prev = NULL; 85 q->prev = p; 86 l->head = p; 87 } 88 } else { 89 l->tail->next = p; 90 p->next = NULL; 91 p->prev = l->tail; 92 l->tail = p; 93 } 94 } 95 } 96 97 delete(l, p) 98 LIST *l; 99 PLANE *p; 100 { 101 if (l->head == NULL) 102 loser(p, "deleted a non-existant plane! Get help!"); 103 104 if (l->head == p && l->tail == p) 105 l->head = l->tail = NULL; 106 else if (l->head == p) { 107 l->head = p->next; 108 l->head->prev = NULL; 109 } else if (l->tail == p) { 110 l->tail = p->prev; 111 l->tail->next = NULL; 112 } else { 113 p->prev->next = p->next; 114 p->next->prev = p->prev; 115 } 116 } 117