blob: 4619b4d147ece41a84f17ebf7c2016bbc949681f (
plain)
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
|
#pragma once
#include <atomic>
#include <chrono>
#include <mutex>
#include <optional>
#include <string>
namespace base
{
// This is a helper thread-safe class which can be mixed in
// classes which represent some cancellable activities.
class Cancellable
{
public:
enum class Status
{
Active,
CancelCalled,
DeadlineExceeded,
};
Cancellable() = default;
virtual ~Cancellable() {}
// Marks current activity as not cancelled.
// Resets the deadline if it was present.
virtual void Reset();
// Marks current activity as cancelled.
virtual void Cancel();
// Sets a deadline after which the activity is cancelled.
virtual void SetDeadline(std::chrono::steady_clock::time_point const & t);
// Updates the status.
// Returns true iff current activity has been cancelled (either by the call
// to Cancel or by timeout).
virtual bool IsCancelled() const;
// Updates the status of current activity and returns its value.
virtual Status CancellationStatus() const;
private:
// Checks whether |m_deadline| has exceeded. Must be called with |m_mutex| locked.
void CheckDeadline() const;
mutable std::mutex m_mutex;
mutable Status m_status = Status::Active;
std::optional<std::chrono::steady_clock::time_point> m_deadline;
};
std::string DebugPrint(Cancellable::Status status);
} // namespace base
|
