src/common/fixed_size_queue.h


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

// Copyright 2013 Dolphin Emulator Project
// Licensed under GPLv2
// Refer to the license.txt file included.

#pragma once

// STL-look-a-like interface, but name is mixed case to distinguish it clearly from the
// real STL classes.

// Not fully featured, no safety checking yet. Add features as needed.

// TODO: "inline" storage?

template <class T, int N>
class fixed_size_queue.h
{
    T *storage;
    int head;
    int tail;
    int count;  // sacrifice 4 bytes for a simpler implementation. may optimize away in the future.

    // Make copy constructor private for now.
    fixed_size_queue.h(fixed_size_queue.h &other) {    }

public:
    fixed_size_queue.h()
    {
        storage = new T[N];
        clear();
    }

    ~fixed_size_queue.h()
    {
        delete [] storage;
    }

    void clear() {
        head = 0;
        tail = 0;
        count = 0;
    }

    void push(T t) {
        storage[tail] = t;
        tail++;
        if (tail == N)
            tail = 0;
        count++;
    }

    void pop() {
        head++;
        if (head == N)
            head = 0;
        count--;
    }

    T pop_front() {
        const T &temp = storage[head];
        pop();
        return temp;
    }

    T &front() { return storage[head]; }
    const T &front() const { return storage[head]; }

    size_t size() const {
        return count;
    }
};