1// Copyright (c) 2023-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#ifndef BITCOIN_UTIL_SIGNALINTERRUPT_H
6#define BITCOIN_UTIL_SIGNALINTERRUPT_H
7
8#ifdef WIN32
9#include <condition_variable>
10#include <mutex>
11#else
12#include <util/tokenpipe.h>
13#endif
14
15#include <atomic>
16
17namespace util {
18/**
19 * Helper class that manages an interrupt flag, and allows a thread or
20 * signal to interrupt another thread.
21 *
22 * This class is safe to be used in a signal handler. If sending an interrupt
23 * from a signal handler is not necessary, the more lightweight \ref
24 * CThreadInterrupt class can be used instead.
25 */
26
27class SignalInterrupt
28{
29public:
30    SignalInterrupt();
31    explicit operator bool() const;
32    [[nodiscard]] bool operator()();
33    [[nodiscard]] bool reset();
34    [[nodiscard]] bool wait();
35
36private:
37    std::atomic<bool> m_flag;
38
39#ifndef WIN32
40    // On UNIX-like operating systems use the self-pipe trick.
41    TokenPipeEnd m_pipe_r;
42    TokenPipeEnd m_pipe_w;
43#else
44    // On windows use a condition variable, since we don't have any signals there
45    std::mutex m_mutex;
46    std::condition_variable m_cv;
47#endif
48};
49} // namespace util
50
51#endif // BITCOIN_UTIL_SIGNALINTERRUPT_H
52