libreoffice-online/common/SigUtil.hpp

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
/*
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */

#pragma once

#include <atomic>
#include <mutex>
#include <signal.h>

namespace SigUtil
{
#ifndef IOS
    /// Get the flag used to commence clean shutdown.
    /// requestShutdown() is used to set the flag.
    bool getShutdownRequestFlag();

    /// Get the flag to stop pump loops forcefully.
    /// If this returns true, getShutdownRequestFlag() must also return true.
    bool getTerminationFlag();
    /// Set the flag to stop pump loops forcefully and request shutting down.
    void setTerminationFlag();
#if MOBILEAPP
    /// Reset the flags to stop pump loops forcefully.
    /// Only necessary in Mobile.
    void resetTerminationFlags();
#endif
#else
    // In the mobile apps we have no need to shut down the app.
    inline constexpr bool getShutdownRequestFlag()
    {
        return false;
    }

    inline constexpr bool getTerminationFlag()
    {
        return false;
    }

    inline void setTerminationFlag()
    {
    }
#endif

    extern "C" { typedef void (*GlobalDumpStateFn)(void); }

    void checkDumpGlobalState(GlobalDumpStateFn dumpState);

    /// Add a message to a round-robin buffer to be dumped on fatal signal
    void addActivity(const std::string &message);

    /// Called to flag that we are running in unattended mode, not interactive.
    /// In unattended mode we know there is no one to attach a debugger on
    /// faulting, so we do not wait unnecessarily. Otherwise, we wait for 60s.
    void setUnattended();

#if !MOBILEAPP
    /// Wait for the signal handler, if any,
    /// and prevent _Exit while collecting backtrace.
    void waitSigHandlerTrap();

    /// Returns the name of the signal.
    const char* signalName(int signo);

    /// Register a wakeup function when changing

    /// Trap signals to cleanup and exit the process gracefully.
    void setTerminationSignals();

    /// Trap all fatal signals to assist debugging.
    void setFatalSignals(const std::string &versionInfo);

    /// Update version info
    void setVersionInfo(const std::string &versionInfo);

    /// Trap generally useful signals
    void setUserSignals();

    /// Trap to unpause the process
    void setDebuggerSignal();

    /// Requests the server to initiate graceful shutdown.
    /// Shutting down is a multi-stage process, because
    /// it can be requested via signals.
    /// Since we need to notify clients, we can't
    /// invoke the sockets while in a signal handler.
    /// This flags the server to notify clients first
    /// then flags for shutdown.
    void requestShutdown();

    /// Kills a child process and returns true when
    /// child pid is removed from the process table
    /// after a certain (short) timeout.
    bool killChild(const int pid, const int signal = SIGKILL);

    /// Dump a signal-safe back-trace
    void dumpBacktrace();

#endif // !MOBILEAPP

} // end namespace SigUtil

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