[unix-history] / games / atc / list.c

/*-
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Ed James.
 *
 * 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 */

/*
 * Copyright (c) 1987 by Ed James, UC Berkeley.  All rights reserved.
 *
 * Copy permission is hereby granted provided that this notice is
 * retained on all partial or complete copies.
 *
 * For more info on this and all of my stuff, mail edjames@berkeley.edu.
 */

#ifndef lint
static char sccsid[] = "@(#)list.c	5.2 (Berkeley) 4/30/90";
#endif /* not lint */

#include "include.h"

PLANE	*
newplane()
{
	return ((PLANE *) calloc(1, sizeof (PLANE)));
}

append(l, p)
	LIST	*l;
	PLANE	*p;
{
	PLANE 	*q = NULL, *r = NULL;

	if (l->head == NULL) {
		p->next = p->prev = NULL;
		l->head = l->tail = p;
	} else {
		q = l -> head;

		while (q != NULL && q->plane_no < p->plane_no) {
			r = q;
			q = q -> next;
		}

		if (q) {
			if (r) {
				p->prev = r;
				r->next = p;
				p->next = q;
				q->prev = p;
			} else {
				p->next = q;
				p->prev = NULL;
				q->prev = p;
				l->head = p;
			}
		} else {
			l->tail->next = p;
			p->next = NULL;
			p->prev = l->tail;
			l->tail = p;
		}
	}
}

delete(l, p)
	LIST	*l;
	PLANE	*p;
{
	if (l->head == NULL)
		loser(p, "deleted a non-existant plane! Get help!");
	
	if (l->head == p && l->tail == p)
		l->head = l->tail = NULL;
	else if (l->head == p) {
		l->head = p->next;
		l->head->prev = NULL;
	} else if (l->tail == p) {
		l->tail = p->prev;
		l->tail->next = NULL;
	} else {
		p->prev->next = p->next;
		p->next->prev = p->prev;
	}
}
Commit	Line	Data
15637ed4 RG	1	/*-
	2	* Copyright (c) 1990 The Regents of the University of California.
	3	* 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
	37	/*
	38	* Copyright (c) 1987 by Ed James, UC Berkeley. All rights reserved.
	39	*
	40	* Copy permission is hereby granted provided that this notice is
	41	* retained on all partial or complete copies.
	42	*
	43	* For more info on this and all of my stuff, mail edjames@berkeley.edu.
	44	*/
	45
	46	#ifndef lint
	47	static char sccsid[] = "@(#)list.c 5.2 (Berkeley) 4/30/90";
	48	#endif /* not lint */
	49
	50	#include "include.h"
	51
	52	PLANE *
	53	newplane()
	54	{
	55	return ((PLANE *) calloc(1, sizeof (PLANE)));
	56	}
	57
	58	append(l, p)
	59	LIST *l;
	60	PLANE *p;
	61	{
	62	PLANE q = NULL, r = NULL;
	63
	64	if (l->head == NULL) {
65	p->next = p->prev = NULL;
66	l->head = l->tail = p;
67	} else {
68	q = l -> head;
69
70	while (q != NULL && q->plane_no < p->plane_no) {
71	r = q;
72	q = q -> next;
73	}
74
75	if (q) {
76	if (r) {
77	p->prev = r;
78	r->next = p;
79	p->next = q;
80	q->prev = p;
81	} else {
82	p->next = q;
83	p->prev = NULL;
84	q->prev = p;
85	l->head = p;
86	}
87	} else {
88	l->tail->next = p;
89	p->next = NULL;
90	p->prev = l->tail;
91	l->tail = p;
92	}
93	}
94	}
95
96	delete(l, p)
97	LIST *l;
98	PLANE *p;
99	{
100	if (l->head == NULL)
101	loser(p, "deleted a non-existant plane! Get help!");
102
103	if (l->head == p && l->tail == p)
104	l->head = l->tail = NULL;
105	else if (l->head == p) {
106	l->head = p->next;
107	l->head->prev = NULL;
108	} else if (l->tail == p) {
109	l->tail = p->prev;
110	l->tail->next = NULL;
111	} else {
112	p->prev->next = p->next;
113	p->next->prev = p->prev;
114	}
115	}