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
|
#pragma once
//
// Copyright(c) 2018 Gabi Melman.
// Distributed under the MIT License (http://opensource.org/licenses/MIT)
//
// multi producer-multi consumer blocking queue.
// enqueue(..) - will block until room found to put the new message.
// enqueue_nowait(..) - will return immediately with false if no room left in
// the queue.
// dequeue_for(..) - will block until the queue is not empty or timeout have
// passed.
#include "spdlog/details/circular_q.h"
#include <condition_variable>
#include <mutex>
namespace spdlog {
namespace details {
template<typename T>
class mpmc_blocking_queue
{
public:
using item_type = T;
explicit mpmc_blocking_queue(size_t max_items)
: q_(max_items)
{
}
#ifndef __MINGW32__
// try to enqueue and block if no room left
void enqueue(T &&item)
{
{
std::unique_lock<std::mutex> lock(queue_mutex_);
pop_cv_.wait(lock, [this] { return !this->q_.full(); });
q_.push_back(std::move(item));
}
push_cv_.notify_one();
}
// enqueue immediately. overrun oldest message in the queue if no room left.
void enqueue_nowait(T &&item)
{
{
std::unique_lock<std::mutex> lock(queue_mutex_);
q_.push_back(std::move(item));
}
push_cv_.notify_one();
}
// try to dequeue item. if no item found. wait upto timeout and try again
// Return true, if succeeded dequeue item, false otherwise
bool dequeue_for(T &popped_item, std::chrono::milliseconds wait_duration)
{
{
std::unique_lock<std::mutex> lock(queue_mutex_);
if (!push_cv_.wait_for(lock, wait_duration, [this] { return !this->q_.empty(); }))
{
return false;
}
q_.pop_front(popped_item);
}
pop_cv_.notify_one();
return true;
}
#else
// apparently mingw deadlocks if the mutex is released before cv.notify_one(),
// so release the mutex at the very end each function.
// try to enqueue and block if no room left
void enqueue(T &&item)
{
std::unique_lock<std::mutex> lock(queue_mutex_);
pop_cv_.wait(lock, [this] { return !this->q_.full(); });
q_.push_back(std::move(item));
push_cv_.notify_one();
}
// enqueue immediately. overrun oldest message in the queue if no room left.
void enqueue_nowait(T &&item)
{
std::unique_lock<std::mutex> lock(queue_mutex_);
q_.push_back(std::move(item));
push_cv_.notify_one();
}
// try to dequeue item. if no item found. wait upto timeout and try again
// Return true, if succeeded dequeue item, false otherwise
bool dequeue_for(T &popped_item, std::chrono::milliseconds wait_duration)
{
std::unique_lock<std::mutex> lock(queue_mutex_);
if (!push_cv_.wait_for(lock, wait_duration, [this] { return !this->q_.empty(); }))
{
return false;
}
q_.pop_front(popped_item);
pop_cv_.notify_one();
return true;
}
#endif
size_t overrun_counter()
{
std::unique_lock<std::mutex> lock(queue_mutex_);
return q_.overrun_counter();
}
private:
std::mutex queue_mutex_;
std::condition_variable push_cv_;
std::condition_variable pop_cv_;
spdlog::details::circular_q<T> q_;
};
} // namespace details
} // namespace spdlog
|
