Lothal-HTTP/ThreadSafeQueue.h at main · ShantanuGV/Lothal-HTTP · GitHub

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
#pragma once

#include <iostream>
#include <queue>
#include <mutex>
#include <condition_variable>
#include <utility>
using namespace std;

template<typename T>
class ThreadSafeQueue{
    public:
        ThreadSafeQueue();

        void push(const T &value);

        void push(T &&value);

        bool pop(T &value);

        void stop();

        bool empty() const;

        size_t size() const;

    private:
        queue<T> queue;

        mutable mutex mutex;

        condition_variable condition;

        bool stopped;
};

// =============================
// Implementation
// =============================

template<typename T>
ThreadSafeQueue<T>::ThreadSafeQueue()
    : stopped(false)
{
}

template<typename T>
void ThreadSafeQueue<T>::push(const T& value)
{
    {
        std::lock_guard<std::mutex> lock(mutex);

        if(stopped)
            return;

        queue.push(value);
    }

    condition.notify_one();
}

template<typename T>
void ThreadSafeQueue<T>::push(T&& value)
{
    {
        std::lock_guard<std::mutex> lock(mutex);

        if(stopped)
            return;

        queue.push(std::move(value));
    }

    condition.notify_one();
}

template<typename T>
bool ThreadSafeQueue<T>::pop(T& value)
{
    std::unique_lock<std::mutex> lock(mutex);

    condition.wait(lock,
    [this]()
    {
        return stopped || !queue.empty();
    });

    if(stopped && queue.empty())
    {
        return false;
    }

    value = std::move(queue.front());

    queue.pop();

    return true;
}

template<typename T>
void ThreadSafeQueue<T>::stop()
{
    {
        std::lock_guard<std::mutex> lock(mutex);

        stopped = true;
    }

    condition.notify_all();
}

template<typename T>
bool ThreadSafeQueue<T>::empty() const
{
    std::lock_guard<std::mutex> lock(mutex);

    return queue.empty();
}

template<typename T>
size_t ThreadSafeQueue<T>::size() const
{
    std::lock_guard<std::mutex> lock(mutex);

    return queue.size();
}