signal_handler.h

Go to the documentation of this file.

 
#pragma once
 
#include <atomic>
#include <condition_variable>
#include <csignal>
#include <functional>
#include <mutex>
 
namespace kcenon::pacs::samples {
 
class signal_handler {
public:
    using shutdown_callback = std::function<void()>;
 
    // ========================================================================
    // Static Interface
    // ========================================================================
 
    static void install(shutdown_callback callback = nullptr);
 
    [[nodiscard]] static auto should_shutdown() noexcept -> bool;
 
    static void wait_for_shutdown();
 
    static void request_shutdown();
 
    static void reset();
 
private:
    static void handler(int signal);
 
    static std::atomic<bool> shutdown_requested_;
 
    static shutdown_callback callback_;
 
    static std::mutex mutex_;
 
    static std::condition_variable cv_;
 
    static std::atomic<bool> callback_invoked_;
};
 
// ============================================================================
// RAII Wrapper
// ============================================================================
 
class scoped_signal_handler {
public:
    explicit scoped_signal_handler(signal_handler::shutdown_callback callback = nullptr);
 
    ~scoped_signal_handler();
 
    // Non-copyable, non-movable
    scoped_signal_handler(const scoped_signal_handler&) = delete;
    auto operator=(const scoped_signal_handler&) -> scoped_signal_handler& = delete;
    scoped_signal_handler(scoped_signal_handler&&) = delete;
    auto operator=(scoped_signal_handler&&) -> scoped_signal_handler& = delete;
 
    void wait();
 
    [[nodiscard]] auto should_shutdown() const noexcept -> bool;
};
 
}  // namespace kcenon::pacs::samples