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/*
* This file is part of buteo-syncfw package
*
* Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
*
* Contact: Sateesh Kavuri <sateesh.kavuri@nokia.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* version 2.1 as published by the Free Software Foundation.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
*/
#ifndef SYNCSIGHANDLER_H
#define SYNCSIGHANDLER_H
#include <QSocketNotifier>
/*! \brief About this class.
* We can't call Qt functions from Unix signal handlers.We can only call async-signal-safe functions from signal handlers.
* So this provides a way to use Unix signal handlers with Qt. The strategy is to have our Unix signal handler will eventually
* cause a Qt signal to be emitted, and then we simply return from our Unix signal handler.
* Back in our Qt program, that Qt signal gets emitted and then received by our Qt slot function, where we are safely doing Qt stuff
* which weren't allowed to do in the Unix signal handler.
* One simple way to make this happen is declares a socket pair in our class for each Unix signal we want to handle.
* The socket pairs are declared as static data members.We also created a QSocketNotifier to monitor the read end of each socket pair,
* declare your Unix signal handlers to be static class methods, and declare a slot function corresponding to each of our
* Unix signal handlers. In this class, we intend to handle both the SIGHUP and SIGTERM signals.
*/
class SyncSigHandler : public QObject
{
Q_OBJECT
public:
/*! \brief Constructor
*
* @param aParent object
* @param aName const char
*/
SyncSigHandler(QObject *aParent = 0, const char *aName = 0);
/*! \brief Destructor
*
*/
~SyncSigHandler();
// Unix signal handlers.
static void hupSignalHandler(int unused);
static void termSignalHandler(int unused);
public slots:
/*! \brief QT signal handler to handle SIG_HUP
*
* @return None
*/
void handleSigHup();
/*! \brief QT signal handler to handle SIG_TERM
*
* @return None
*/
void handleSigTerm();
private:
//socket pair for each Unix signal to handle
static int iSigHupFd[2];
static int iSigTermFd[2];
//QSocketNotifier to monitor the read end of each socket pair,
// declare your Unix signal handlers to be static class methods
QSocketNotifier *iSigHup;
QSocketNotifier *iSigTerm;
#ifdef SYNCFW_UNIT_TESTS
friend class SyncSigHandlerTest;
#endif
};
#endif // SYNCSIGHANDLER_H
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