1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
|
//
// Queue.cc
//
// Queue: This class implements a linked list of objects. It itself is also an
// object
//
// Part of the ht://Dig package <https://htdig.sourceforge.net/>
// Copyright (c) 1999-2004 The ht://Dig Group
// For copyright details, see the file COPYING in your distribution
// or the GNU Library General Public License (LGPL) version 2 or later
// <http://www.gnu.org/copyleft/lgpl.html>
//
// $Id: Queue.cc,v 1.6 2004/05/28 13:15:21 lha Exp $
//
#ifdef HAVE_CONFIG_H
#include "htconfig.h"
#endif /* HAVE_CONFIG_H */
#include "Queue.h"
struct Queuenode
{
Queuenode *next;
Object *obj;
};
//***************************************************************************
// Queue::Queue()
//
Queue::Queue()
{
head = tail = 0;
size = 0;
}
//***************************************************************************
// Queue::~Queue()
//
Queue::~Queue()
{
destroy();
}
//***************************************************************************
// void Queue::destroy()
//
void Queue::destroy()
{
while (head)
{
Object *obj = pop();
delete obj;
}
size = 0;
head = tail = 0;
}
//***************************************************************************
// void Queue::push(Object *obj)
// Push an object onto the Queue.
//
void Queue::push(Object *obj)
{
Queuenode *node = new Queuenode;
node->obj = obj;
node->next = 0;
if (tail)
((Queuenode *) tail)->next = node;
tail = node;
if (!head)
head = tail;
size++;
}
//***************************************************************************
// Object *Queue::pop()
// Return the object at the head of the Queue and remove it
//
Object *Queue::pop()
{
if (size == 0)
return 0;
Queuenode *node = (Queuenode *) head;
Object *obj = node->obj;
head = (void *) node->next;
delete node;
size--;
if (!head)
tail = 0;
return obj;
}
//***************************************************************************
// Object *Queue::peek()
// Return the object at the top of the Queue.
//
Object *Queue::peek()
{
if (size == 0)
return 0;
return ((Queuenode *)head)->obj;
}
|
