Dispatcher.h

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/*
 *  This file was originally part of the "D-Bus++ - C++ bindings for D-Bus":
 *
 *          include/dbus-c++/eventloop-integration.h
 *
 *  I found the BusDispatcher to be... not so great. I was eventually able to
 *  get it to work. All I wanted to do was be able to wait until a signal to
 *  arrive. To do that, I had to use a "dispatcher". I did not want to hitch
 *  my wagon to glib or qt or ..., but only wanted a simple minimal dispatcher.
 *  Thus, despite admonitions to the contrary, I adopted the "BusDispatcher".
 *  the signal I was waiting for was delivered to my callback promptly, but
 *  I found that there was a pregnant pause between when I told the dispatcher
 *  to "leave( )" undoubtedly because of timeouts in polling. I tried to
 *  create a subclass of BusDispatcher, but because all of the _mutex_*
 *  were private to the DefaultMainLoop (what a mess). At that point,
 *  decided to implement my own, minimal, dispatcher. It is hard to believe
 *  this should be necessary, but apparently so.
 *
 *  Copyright (C) 2005-2007  Paolo Durante <shackan@gmail.com>
 *  Copyright (C) 2009       Associated Universities Inc.
 *
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 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
 *  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */


#ifndef DBUS_DISPATCHER_H_
#define DBUS_DISPATCHER_H_

#include <dbus-c++/dbus.h>
#include <dbus-c++/connection.h>

namespace casa {
    namespace dbus {

        class Dispatcher;

        class Timeout : public DBus::Timeout {
            public:
                Timeout( DBus::Timeout::Internal *, Dispatcher *);
                ~Timeout( );
                void toggle();
                DBus::Slot<void, Timeout &> expired;
        
            private:
                bool _enabled;
                int _interval;
                bool _repeat;

                double _expiration;
/*              void *_data; */
        
                Dispatcher *_disp;
                friend class Dispatcher;
        };

        class Watch : public DBus::Watch {

            public:
                Watch( DBus::Watch::Internal *, Dispatcher *);
                ~Watch( );
                void toggle();

                DBus::Slot<void, Watch &> ready;

            private:
                bool _enabled;

                int _fd;
                int _flags;
                int _state;

/*              void *_data; */

                Dispatcher *_disp;
                friend class Dispatcher;
        };

                class Dispatcher : public DBus::Dispatcher {

                        public:
                                Dispatcher();
                                ~Dispatcher();

                                // pure virtual functions from Dispatcher
                                void enter();
                                void leave();

                                DBus::Timeout *add_timeout(DBus::Timeout::Internal *);
                                void rem_timeout(DBus::Timeout *);

                                DBus::Watch *add_watch(DBus::Watch::Internal *);
                                void rem_watch(DBus::Watch *);

                                // helper function
                                void do_iteration();
                                void watch_ready(Watch &);
                                void timeout_expired(Timeout &);

                                void dispatch( );

                        private:
                                DBus::DefaultMutex _mutex_t;
                                std::list<Timeout*> _timeouts;

                                DBus::DefaultMutex _mutex_w;
                                std::list<Watch*> _watches;

                                bool _running;
                                int _leave_pipe[2];
                                friend class Timeout;
                                friend class Watch;
                };
    }
}

#endif