1 /*
2  * Copyright (c) 2007, Michael Feathers, James Grenning and Bas Vodde
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are met:
7  *     * Redistributions of source code must retain the above copyright
8  *       notice, this list of conditions and the following disclaimer.
9  *     * Redistributions in binary form must reproduce the above copyright
10  *       notice, this list of conditions and the following disclaimer in the
11  *       documentation and/or other materials provided with the distribution.
12  *     * Neither the name of the <organization> nor the
13  *       names of its contributors may be used to endorse or promote products
14  *       derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE EARLIER MENTIONED AUTHORS ``AS IS'' AND ANY
17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19  * DISCLAIMED. IN NO EVENT SHALL <copyright holder> BE LIABLE FOR ANY
20  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
23  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include "CircularBuffer.h"
29 #include "Printer.h"
30 #include <stddef.h>
31 
CircularBuffer(int _capacity)32 CircularBuffer::CircularBuffer(int _capacity) :
33     index(0), outdex(0), capacity(_capacity), empty(true), full(false)
34 {
35     buffer = new int[(size_t) this->capacity];
36 }
37 
~CircularBuffer()38 CircularBuffer::~CircularBuffer()
39 {
40     delete[] buffer;
41 }
42 
IsEmpty()43 bool CircularBuffer::IsEmpty()
44 {
45     return empty;
46 }
47 
IsFull()48 bool CircularBuffer::IsFull()
49 {
50     return full;
51 }
52 
Put(int i)53 void CircularBuffer::Put(int i)
54 {
55     empty = false;
56     buffer[index] = i;
57     index = Next(index);
58     if (full) outdex = Next(outdex);
59     else if (index == outdex) full = true;
60 }
61 
Get()62 int CircularBuffer::Get()
63 {
64     int result = -1;
65     full = false;
66 
67     if (!empty) {
68         result = buffer[outdex];
69         outdex = Next(outdex);
70         if (outdex == index) empty = true;
71     }
72     return result;
73 }
74 
Capacity()75 int CircularBuffer::Capacity()
76 {
77     return capacity;
78 }
79 
Next(int i)80 int CircularBuffer::Next(int i)
81 {
82     if (++i >= capacity) i = 0;
83     return i;
84 }
85 
Print(Printer * p)86 void CircularBuffer::Print(Printer* p)
87 {
88     p->Print("Circular buffer content:\n<");
89 
90     int printIndex = outdex;
91     int count = index - outdex;
92 
93     if (!empty && (index <= outdex)) count = capacity - (outdex - index);
94 
95     for (int i = 0; i < count; i++) {
96         p->Print(buffer[printIndex]);
97         printIndex = Next(printIndex);
98         if (i + 1 != count) p->Print(", ");
99     }
100     p->Print(">\n");
101 }
102