kio/kio/kdbusservicestarter.h

   1 /* This file is part of the KDE libraries
   2    Copyright (C) 2003 David Faure <faure@kde.org>
   3
   4    This library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public
   6    License version 2 as published by the Free Software Foundation.
   7
   8    This library is distributed in the hope that it will be useful,
   9    but WITHOUT ANY WARRANTY; without even the implied warranty of
  10    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11    Library General Public License for more details.
  12
  13    You should have received a copy of the GNU Library General Public License
  14    along with this library; see the file COPYING.LIB.  If not, write to
  15    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  16    Boston, MA 02110-1301, USA.
  17 */
  18
  19 #ifndef KDBUSSERVICESTARTER_H
  20 #define KDBUSSERVICESTARTER_H
  21
  22 #include <kio/kio_export.h>
  23
  24 #include <QtCore/QString>
  25
  26 class KDBusServiceStarterPrivate;
  27
  28 /**
  29  * A generic DBUS service starter, using KServiceTypeTrader.
  30  * The default implementation starts new processes, but this interface can
  31  * also be reimplemented by specific applications to provide dlopened in-process DBus objects.
  32  * This interface is similar to the startServiceByName() function found in QDBusBusService, but
  33  * with the added benefit of using KTrader (and, therefore, additional constraints and the
  34  * ability to search the standard KDE dirs).
  35  * @author David Faure <faure@kde.org>
  36  */
  37 class KIO_EXPORT KDBusServiceStarter { //krazy:exclude=dpointer (uses K_GLOBAL_STATIC)
  38 public:
  39
  40     static KDBusServiceStarter* self();
  41
  42     /**
  43      * Check if a given DBus service is available - from the serviceType it's supposed to implement.
  44      *
  45      * The trader is queried to find the preferred application for this serviceType,
  46      * with the constraint that its X-DBus-ServiceName property must be defined.
  47      * Then the DBus server is checked. If the service is not available,
  48      * this method will call startServiceFor to start it.
  49      *
  50      * @param serviceType the type of service we're looking for
  51      * @param constraint see KServiceTypeTrader
  52      * @param error On failure, @p error contains a description of the error
  53      *         that occurred. If the pointer is 0, the argument will be
  54      *         ignored
  55      * @param dbusService On success, @p dbusService contains the DBus service name
  56      *         under which this service is available. If the pointer is 0 the argument
  57      *         will be ignored
  58      * @param flags for future extensions (currently unused)
  59      *
  60      * @return an error code indicating success (== 0) or failure (> 0).
  61      */
  62     int findServiceFor( const QString& serviceType,
  63                         const QString& constraint = QString(),
  64                         QString *error=0, QString* dbusService=0,
  65                         int flags=0 );
  66
  67     /**
  68      * Find an implementation of the given @p serviceType,
  69      * and start it, to use its DBus interface.
  70      * The default implementation uses KServiceTypeTrader to find the preferred Application,
  71      * and then starts it using KToolInvocation::startService...
  72      *
  73      * However applications (like kontact) can reimplement this method, to provide
  74      * an in-process way of loading the implementation for this service type.
  75      *
  76      * @param serviceType the type of service we're looking for
  77      * @param constraint see KServiceTypeTrader
  78      * @param error On failure, @p error contains a description of the error
  79      *         that occurred. If the pointer is 0, the argument will be
  80      *         ignored
  81      * @param dbusService On success, @p dbusService contains the DBus service name
  82      *         under which this service is available. If the pointer is 0 the argument
  83      *         will be ignored
  84      * @param flags for future extensions (currently unused)
  85      *
  86      * @return an error code indicating success (== 0) or failure (> 0).
  87      */
  88     virtual int startServiceFor( const QString& serviceType,
  89                                  const QString& constraint = QString(),
  90                                  QString *error=0, QString* dbusService=0,
  91                                  int flags=0 );
  92 protected:
  93     friend class KDBusServiceStarterPrivate;
  94     KDBusServiceStarter();
  95     virtual ~KDBusServiceStarter();
  96 };
  97
  98 #endif
  99