1//
2//  LinkBase.m
3//  ANTLR
4//
5//  Created by Alan Condit on 6/14/10.
6//  [The "BSD licence"]
7//  Copyright (c) 2010 Alan Condit
8//  All rights reserved.
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. The name of the author may not be used to endorse or promote products
19//    derived from this software without specific prior written permission.
20//
21// THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22// IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23// OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24// IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26// NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30// THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31
32#import "LinkBase.h"
33
34@implementation LinkBase
35
36@synthesize fPrev;
37@synthesize fNext;
38
39+(id<LinkList>)newLinkBase
40{
41	return [[LinkBase alloc] init];
42}
43
44+(id<LinkList>)newLinkBase:(id<LinkList>)np Prev:(id<LinkList>)pp
45{
46	return [[LinkBase alloc] initWithPtr:np Prev:pp];
47}
48
49-(id<LinkList>)init
50{
51	if ((self = [super init]) != nil) {
52		fNext = nil;
53		fPrev = nil;
54	}
55	return(self);
56}
57
58-(id<LinkList>)initWithPtr:(id<LinkList>)np Prev:(id<LinkList>)pp
59{
60	if ((self = [super init]) != nil) {
61		fNext = np;
62		fPrev = pp;
63	}
64	return(self);
65}
66
67-(void)dealloc
68{
69#ifdef DEBUG_DEALLOC
70    NSLog( @"called dealloc in LinkBase" );
71#endif
72	if (fNext) [fNext release];
73	if (fPrev) [fPrev release];
74	[super dealloc];
75}
76
77- (id) copyWithZone:(NSZone *)aZone
78{
79    LinkBase *copy;
80
81    copy = [[self class] allocWithZone:aZone];
82    copy.fPrev = fPrev;
83    copy.fNext = fNext;
84    return( copy );
85}
86
87-(id<LinkList>)append:(id<LinkList>)node
88{
89	node.fPrev = (id<LinkList>)self;
90	node.fNext = (id<LinkList>)self.fNext;
91	if (node.fNext != nil)
92        node.fNext.fPrev = node;
93    self.fNext = node;
94    return( node );
95}
96
97-(id<LinkList>)insert:(id<LinkList>)node
98{
99	node.fNext = self;
100	node.fPrev = self.fPrev;
101    if (node.fPrev != nil)
102        node.fPrev.fNext = node;
103	self.fPrev = node;
104	return( node );
105}
106
107-(id<LinkList>)getfNext
108{
109	return(fNext);
110}
111
112-(void)setfNext:(id<LinkList>)np
113{
114	fNext = np;
115}
116
117-(id<LinkList>)getfPrev
118{
119	return(fPrev);
120}
121
122-(void)setfPrev:(id<LinkList>)pp
123{
124	fPrev = pp;
125}
126
127@end
128