src/kitemviews/private/kdirectorycontentscounter.cpp

   1 /***************************************************************************
   2  *   Copyright (C) 2011 by Peter Penz <peter.penz19@gmail.com>             *
   3  *   Copyright (C) 2013 by Frank Reininghaus <frank78ac@googlemail.com>    *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
  19  ***************************************************************************/
  20
  21 #include "kdirectorycontentscounter.h"
  22 #include "kitemviews/kfileitemmodel.h"
  23
  24 #include <KDirWatch>
  25
  26 #include <QFileInfo>
  27 #include <QDir>
  28 #include <QThread>
  29
  30 namespace  {
  31     /// cache of directory counting result
  32     static QHash<QString, QPair<int, long>> *s_cache;
  33 }
  34
  35 KDirectoryContentsCounter::KDirectoryContentsCounter(KFileItemModel* model, QObject* parent) :
  36     QObject(parent),
  37     m_model(model),
  38     m_queue(),
  39     m_worker(nullptr),
  40     m_workerIsBusy(false),
  41     m_dirWatcher(nullptr),
  42     m_watchedDirs()
  43 {
  44     connect(m_model, &KFileItemModel::itemsRemoved,
  45             this,    &KDirectoryContentsCounter::slotItemsRemoved);
  46
  47     if (!m_workerThread) {
  48         m_workerThread = new QThread();
  49         m_workerThread->start();
  50     }
  51
  52     if (s_cache == nullptr) {
  53         s_cache = new QHash<QString, QPair<int, long>>();
  54     }
  55
  56     m_worker = new KDirectoryContentsCounterWorker();
  57     m_worker->moveToThread(m_workerThread);
  58
  59     connect(this,     &KDirectoryContentsCounter::requestDirectoryContentsCount,
  60             m_worker, &KDirectoryContentsCounterWorker::countDirectoryContents);
  61     connect(m_worker, &KDirectoryContentsCounterWorker::result,
  62             this,     &KDirectoryContentsCounter::slotResult);
  63
  64     m_dirWatcher = new KDirWatch(this);
  65     connect(m_dirWatcher, &KDirWatch::dirty, this, &KDirectoryContentsCounter::slotDirWatchDirty);
  66 }
  67
  68 KDirectoryContentsCounter::~KDirectoryContentsCounter()
  69 {
  70     if (m_workerThread->isRunning()) {
  71         // The worker thread will continue running. It could even be running
  72         // a method of m_worker at the moment, so we delete it using
  73         // deleteLater() to prevent a crash.
  74         m_worker->deleteLater();
  75     } else {
  76         // There are no remaining workers -> stop the worker thread.
  77         m_workerThread->quit();
  78         m_workerThread->wait();
  79         delete m_workerThread;
  80         m_workerThread = nullptr;
  81
  82         // The worker thread has finished running now, so it's safe to delete
  83         // m_worker. deleteLater() would not work at all because the event loop
  84         // which would deliver the event to m_worker is not running any more.
  85         delete m_worker;
  86     }
  87 }
  88
  89 void KDirectoryContentsCounter::scanDirectory(const QString& path)
  90 {
  91     startWorker(path);
  92 }
  93
  94 void KDirectoryContentsCounter::slotResult(const QString& path, int count, long size)
  95 {
  96     m_workerIsBusy = false;
  97
  98     const QFileInfo info = QFileInfo(path);
  99     const QString resolvedPath = info.canonicalFilePath();
 100
 101     if (!m_dirWatcher->contains(resolvedPath)) {
 102         m_dirWatcher->addDir(resolvedPath);
 103         m_watchedDirs.insert(resolvedPath);
 104     }
 105
 106     if (!m_priorityQueue.isEmpty()) {
 107         startWorker(m_priorityQueue.takeFirst());
 108     } else if (!m_queue.isEmpty()) {
 109         startWorker(m_queue.takeFirst());
 110     }
 111
 112     if (s_cache->contains(resolvedPath)) {
 113         const auto pair = s_cache->value(resolvedPath);
 114         if (pair.first == count && pair.second == size) {
 115             // no change no need to send another result event
 116             return;
 117         }
 118     }
 119
 120     if (info.dir().path() == m_model->rootItem().url().path()) {
 121         // update cache or overwrite value
 122         // when path is a direct children of the current model root
 123         s_cache->insert(resolvedPath, QPair<int, long>(count, size));
 124     }
 125
 126     // sends the results
 127     emit result(resolvedPath, count, size);
 128 }
 129
 130 void KDirectoryContentsCounter::slotDirWatchDirty(const QString& path)
 131 {
 132     const int index = m_model->index(QUrl::fromLocalFile(path));
 133     if (index >= 0) {
 134         if (!m_model->fileItem(index).isDir()) {
 135             // If INotify is used, KDirWatch issues the dirty() signal
 136             // also for changed files inside the directory, even if we
 137             // don't enable this behavior explicitly (see bug 309740).
 138             return;
 139         }
 140
 141         startWorker(path);
 142     }
 143 }
 144
 145 void KDirectoryContentsCounter::slotItemsRemoved()
 146 {
 147     const bool allItemsRemoved = (m_model->count() == 0);
 148
 149     if (!m_watchedDirs.isEmpty()) {
 150         // Don't let KDirWatch watch for removed items
 151         if (allItemsRemoved) {
 152             for (const QString& path : qAsConst(m_watchedDirs)) {
 153                 m_dirWatcher->removeDir(path);
 154             }
 155             m_watchedDirs.clear();
 156             m_queue.clear();
 157         } else {
 158             QMutableSetIterator<QString> it(m_watchedDirs);
 159             while (it.hasNext()) {
 160                 const QString& path = it.next();
 161                 if (m_model->index(QUrl::fromLocalFile(path)) < 0) {
 162                     m_dirWatcher->removeDir(path);
 163                     it.remove();
 164                 }
 165             }
 166         }
 167     }
 168 }
 169
 170 void KDirectoryContentsCounter::startWorker(const QString& path)
 171 {
 172     const bool alreadyInCache = s_cache->contains(path);
 173     if (alreadyInCache) {
 174         // fast path when in cache
 175         // will be updated later if result has changed
 176         const auto pair = s_cache->value(path);
 177         emit result(path, pair.first, pair.second);
 178     }
 179
 180     if (m_workerIsBusy) {
 181         if (!m_queue.contains(path) && !m_priorityQueue.contains(path)) {
 182             if (alreadyInCache) {
 183                 m_queue.append(path);
 184             } else {
 185                 // append to priority queue
 186                 m_priorityQueue.append(path);
 187             }
 188         }
 189     } else {
 190         KDirectoryContentsCounterWorker::Options options;
 191
 192         if (m_model->showHiddenFiles()) {
 193             options |= KDirectoryContentsCounterWorker::CountHiddenFiles;
 194         }
 195
 196         if (m_model->showDirectoriesOnly()) {
 197             options |= KDirectoryContentsCounterWorker::CountDirectoriesOnly;
 198         }
 199
 200         emit requestDirectoryContentsCount(path, options);
 201         m_workerIsBusy = true;
 202     }
 203 }
 204
 205 QThread* KDirectoryContentsCounter::m_workerThread = nullptr;