src/statusbar/mountpointobservercache.cpp

   1 /***************************************************************************
   2  *   Copyright (C) 2014 by Frank Reininghaus <frank78ac@googlemail.com>    *
   3  *                                                                         *
   4  *   This program is free software; you can redistribute it and/or modify  *
   5  *   it under the terms of the GNU General Public License as published by  *
   6  *   the Free Software Foundation; either version 2 of the License, or     *
   7  *   (at your option) any later version.                                   *
   8  *                                                                         *
   9  *   This program is distributed in the hope that it will be useful,       *
  10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  12  *   GNU General Public License for more details.                          *
  13  *                                                                         *
  14  *   You should have received a copy of the GNU General Public License     *
  15  *   along with this program; if not, write to the                         *
  16  *   Free Software Foundation, Inc.,                                       *
  17  *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA          *
  18  ***************************************************************************/
  19
  20 #include "mountpointobservercache.h"
  21
  22 #include "mountpointobserver.h"
  23
  24 #include <KGlobal>
  25 #include <KMountPoint>
  26
  27 #include <QTimer>
  28
  29 class MountPointObserverCacheSingleton
  30 {
  31 public:
  32     MountPointObserverCache instance;
  33 };
  34 K_GLOBAL_STATIC(MountPointObserverCacheSingleton, s_MountPointObserverCache)
  35
  36
  37 MountPointObserverCache::MountPointObserverCache() :
  38     m_observerForMountPoint(),
  39     m_mountPointForObserver(),
  40     m_updateTimer(0)
  41 {
  42     m_updateTimer = new QTimer(this);
  43 }
  44
  45 MountPointObserverCache::~MountPointObserverCache()
  46 {
  47 }
  48
  49 MountPointObserverCache* MountPointObserverCache::instance()
  50 {
  51     return &s_MountPointObserverCache->instance;
  52 }
  53
  54 MountPointObserver* MountPointObserverCache::observerForPath(const QString& path)
  55 {
  56     // Try to share the observer with other paths that have the same mount point.
  57     QString mountPointPath;
  58     KMountPoint::Ptr mountPoint = KMountPoint::currentMountPoints().findByPath(path);
  59     if (mountPoint) {
  60         mountPointPath = mountPoint->mountPoint();
  61     } else {
  62         // Even if determining the mount point failed, KDiskFreeSpaceInfo might still
  63         // be able to retrieve information about the path.
  64         mountPointPath = path;
  65     }
  66
  67     MountPointObserver* observer = m_observerForMountPoint.value(mountPointPath);
  68     if (!observer) {
  69         observer = new MountPointObserver(mountPointPath, this);
  70         m_observerForMountPoint.insert(mountPointPath, observer);
  71         m_mountPointForObserver.insert(observer, mountPointPath);
  72         Q_ASSERT(m_observerForMountPoint.count() == m_mountPointForObserver.count());
  73
  74         connect(observer, SIGNAL(destroyed(QObject*)), this, SLOT(slotObserverDestroyed(QObject*)));
  75
  76         if (!m_updateTimer->isActive()) {
  77             m_updateTimer->start(10000);
  78         }
  79
  80         connect(m_updateTimer, SIGNAL(timeout()), observer, SLOT(update()));
  81     }
  82
  83     return observer;
  84 }
  85
  86 void MountPointObserverCache::slotObserverDestroyed(QObject* observer)
  87 {
  88     Q_ASSERT(m_mountPointForObserver.contains(observer));
  89     const QString& path = m_mountPointForObserver.value(observer);
  90     Q_ASSERT(m_observerForMountPoint.contains(path));
  91     m_observerForMountPoint.remove(path);
  92     m_mountPointForObserver.remove(observer);
  93
  94     Q_ASSERT(m_observerForMountPoint.count() == m_mountPointForObserver.count());
  95
  96     if (m_mountPointForObserver.isEmpty()) {
  97         m_updateTimer->stop();
  98     }
  99 }