goldendict-ng/src/unix/ksignalhandler.hh

/*
    SPDX-FileCopyrightText: 2021 Aleix Pol Gonzalez <aleixpol@kde.org>

    SPDX-License-Identifier: GPL-3.0-or-later

    Copied from KDE's KCoreAddons with minor modifications
*/
#pragma once
#include <QtGlobal>
#ifdef Q_OS_UNIX
  #include <QObject>
  #include <signal.h>

class KSignalHandlerPrivate;

/**
 * Allows getting ANSI C signals and forward them onto the Qt eventloop.
 *
 * It's a singleton as it relies on static data getting defined.
 *
 * \code
 * {
 *   KSignalHandler::self()->watchSignal(SIGTERM);
 *   connect(KSignalHandler::self(), &KSignalHandler::signalReceived,
 *           this, &SomeClass::handleSignal);
 *   job->start();
 * }
 * \endcode
 *
 * @since 5.92
 */
class KSignalHandler: public QObject
{
  Q_OBJECT

public:
  ~KSignalHandler() override;

  /**
   * Adds @p signal to be watched for. Once the process is notified about this signal, @m signalReceived will be emitted with the same @p signal as an
   * argument.
   *
   * @see signalReceived
   */
  void watchSignal( int signal );

  /**
   * Fetches an instance we can use to register our signals.
   */
  static KSignalHandler * self();

Q_SIGNALS:
  /**
   * Notifies that @p signal is emitted.
   *
   * To catch a signal, we need to make sure it's registered using @m watchSignal.
   *
   * @see watchSignal
   */
  void signalReceived( int signal );

private:
  KSignalHandler();

  QScopedPointer< KSignalHandlerPrivate > d;
};

#endif