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
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
|
/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#ifndef TITANIC_FIXED_QUEUE_H
#define TITANIC_FIXED_QUEUE_H
#include "common/scummsys.h"
#include "common/array.h"
namespace Titanic {
/**
* Extremly simple fixed size queue class.
*/
template<class T, uint MAX_SIZE = 10>
class FixedQueue {
typedef uint size_type;
protected:
Common::Array<T> _data;
size_type _topIndex;
public:
FixedQueue<T, MAX_SIZE>() : _topIndex(0) {
_data.reserve(MAX_SIZE);
}
/**
* Returns the size of the queue in use
*/
size_type size() const { return _data.size() - _topIndex; }
/**
* Returns the amount of free remaining space in the queue
*/
size_type freeSize() const { return MAX_SIZE - size(); }
/**
* Returns true if the queue is empty
*/
bool empty() const {
return size() == 0;
}
/**
* Returns true if the queue is full
*/
bool full() const {
return freeSize() == 0;
}
/**
* Clears the queue
*/
void clear() {
_data.clear();
_topIndex = 0;
}
/**
* If the tail of the queue in use has reached the end of the internal
* array, pushes all pending data back to the start of the array
*/
void compact() {
if (_data.size() == MAX_SIZE && _topIndex > 0) {
Common::copy(&_data[_topIndex], &_data[0] + MAX_SIZE, &_data[0]);
_data.resize(size());
_topIndex = 0;
}
}
/**
* Adds a value to the end of the queue
*/
void push(const T &v) {
assert(size() < MAX_SIZE);
compact();
_data.push_back(v);
}
/**
* Returns the top value on the queue
*/
const T &top() const {
assert(size() > 0);
return _data[_topIndex];
}
/**
* Returns the top value on the queue
*/
T &top() {
assert(size() > 0);
return _data[_topIndex];
}
/**
* Pops the top value off the queue
*/
T pop() {
T tmp = top();
++_topIndex;
return tmp;
}
/**
* Returns values from within the queue without popping them
*/
T &operator[](size_type i) {
assert(i < size());
return _data[_topIndex + i];
}
/**
* Returns values from within the queue without popping them
*/
const T &operator[](size_type i) const {
assert(i < size());
return _data[_topIndex + i];
}
};
} // End of namespace Titanic
#endif
|