/* This file is part of the KDE libraries
    Copyright (C) 1997 Christian Czezakte (e9025461@student.tuwien.ac.at)

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    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
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
    Boston, MA 02111-1307, USA.
*/
//
//  KPROCESSCONTROLLER -- A helper class for KProcess
//
//  version 0.3.1, Jan 8th 1997
//
//  (C) Christian Czezatke
//  e9025461@student.tuwien.ac.at
//  Ported by Holger Freyther
//

#ifndef __KPROCCTRL_H__
#define __KPROCCTRL_H__

#include <qvaluelist.h>
#include <qtimer.h>

#include "oprocess.h"

class OProcessControllerPrivate;
class QSocketNotifier;

/**
 * @short Used internally by @ref OProcess
 * @internal
 * @author Christian Czezakte <e9025461@student.tuwien.ac.at>
 *
 *  A class for internal use by OProcess only. -- Exactly one instance
 *  of this class is generated by the first instance of OProcess that is
 *  created (a pointer to it gets stored in @ref theOProcessController ).
 *
 * This class takes care of the actual (UN*X) signal handling.
*/
class OProcessController : public QObject
{
  Q_OBJECT

public:
  OProcessController();
  ~OProcessController();
  //CC: WARNING! Destructor Not virtual (but you don't derive classes from this anyhow...)

public:
 	
  /**
   * Only a single instance of this class is allowed at a time,
   * and this static variable is used to track the one instance.
   */
  static OProcessController *theOProcessController;

  /**
   * Automatically called upon SIGCHLD.
   *
   * Normally you do not need to do anything with this function but
   * if your application needs to disable SIGCHLD for some time for
   * reasons beyond your control, you should call this function afterwards
   * to make sure that no SIGCHLDs where missed.
   */
  static void theSigCHLDHandler(int signal);
  // handler for sigchld
  
  /**
   * @internal
  */
  static void setupHandlers();
  /**
   * @internal
  */
  static void resetHandlers();
  /**
   * @internal
  */
  void addOProcess( OProcess* );
  /**
   * @internal
  */
  void removeOProcess( OProcess* );
 public slots:
  /**
   * @internal
   */
 void slotDoHousekeeping(int socket);

 private slots:
 void delayedChildrenCleanup();
private:
  int fd[2];
  QSocketNotifier *notifier;
  static struct sigaction oldChildHandlerData;
  static bool handlerSet;
  QValueList<OProcess*> processList;
  QTimer delayedChildrenCleanupTimer;

  // Disallow assignment and copy-construction
  OProcessController( const OProcessController& );
  OProcessController& operator= ( const OProcessController& );

  OProcessControllerPrivate *d;
};



#endif