Unity 8
abstractdbusservicemonitor.cpp
1 /*
2  * Copyright (C) 2011-2014 Canonical, Ltd.
3  *
4  * Authors:
5  * Ugo Riboni <ugo.riboni@canonical.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; version 3.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program. If not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "abstractdbusservicemonitor.h"
21 
22 #include <QDBusInterface>
23 #include <QDBusServiceWatcher>
24 #include <QDBusConnection>
25 #include <QDBusConnectionInterface>
26 #include <QDBusReply>
27 
28 AbstractDBusServiceMonitor::AbstractDBusServiceMonitor(const QString &service, const QString &path,
29  const QString &interface, const Bus bus,
30  QObject *parent)
31  : QObject(parent)
32  , m_service(service)
33  , m_path(path)
34  , m_interface(interface)
35  , m_bus(bus)
36  , m_watcher(new QDBusServiceWatcher(service,
37  (bus == SystemBus) ? QDBusConnection::systemBus()
38  : QDBusConnection::sessionBus()))
39  , m_dbusInterface(nullptr)
40 {
41  connect(m_watcher, &QDBusServiceWatcher::serviceRegistered, this, &AbstractDBusServiceMonitor::onServiceRegistered);
42  connect(m_watcher, &QDBusServiceWatcher::serviceUnregistered, this, &AbstractDBusServiceMonitor::onServiceUnregistered);
43 
44  // Connect to the service if it's up already
45  QDBusConnectionInterface* sessionBus = QDBusConnection::sessionBus().interface();
46  QDBusReply<bool> reply = sessionBus->isServiceRegistered(m_service);
47  if (reply.isValid() && reply.value()) {
48  onServiceRegistered(m_service);
49  }
50 }
51 
52 AbstractDBusServiceMonitor::~AbstractDBusServiceMonitor()
53 {
54  delete m_watcher;
55  delete m_dbusInterface;
56 }
57 
58 void AbstractDBusServiceMonitor::onServiceRegistered(const QString &)
59 {
60  if (m_dbusInterface != nullptr) {
61  delete m_dbusInterface;
62  m_dbusInterface = nullptr;
63  }
64 
65  m_dbusInterface = createInterface(m_service, m_path, m_interface,
66  (m_bus == SystemBus) ? QDBusConnection::systemBus()
67  : QDBusConnection::sessionBus());
68  Q_EMIT serviceAvailableChanged(true);
69 }
70 
71 /*
72  * Default implementation creates a QDBusInterface. This performs blocking introspection of the
73  * service at initialization, which may be undesirable if the service is slow/blocked.
74  */
75 QDBusAbstractInterface*
76 AbstractDBusServiceMonitor::createInterface(const QString &service, const QString &path,
77  const QString &interface, const QDBusConnection &connection)
78 {
79  return new QDBusInterface(service, path, interface, connection);
80 }
81 
82 void AbstractDBusServiceMonitor::onServiceUnregistered(const QString &)
83 {
84  if (m_dbusInterface != nullptr) {
85  delete m_dbusInterface;
86  m_dbusInterface = nullptr;
87  }
88 
89  Q_EMIT serviceAvailableChanged(false);
90 }
91 
92 QDBusAbstractInterface* AbstractDBusServiceMonitor::dbusInterface() const
93 {
94  return m_dbusInterface;
95 }
96 
97 bool AbstractDBusServiceMonitor::serviceAvailable() const
98 {
99  return m_dbusInterface != nullptr;
100 }