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.empty()) {
 107         const QString firstPath = m_priorityQueue.front();
 108         m_priorityQueue.pop_front();
 109         startWorker(firstPath);
 110     } else if (!m_queue.empty()) {
 111         const QString firstPath = m_queue.front();
 112         m_queue.pop_front();
 113         startWorker(firstPath);
 114     }
 115
 116     if (s_cache->contains(resolvedPath)) {
 117         const auto pair = s_cache->value(resolvedPath);
 118         if (pair.first == count && pair.second == size) {
 119             // no change no need to send another result event
 120             return;
 121         }
 122     }
 123
 124     if (info.dir().path() == m_model->rootItem().url().path()) {
 125         // update cache or overwrite value
 126         // when path is a direct children of the current model root
 127         s_cache->insert(resolvedPath, QPair<int, long>(count, size));
 128     }
 129
 130     // sends the results
 131     emit result(resolvedPath, count, size);
 132 }
 133
 134 void KDirectoryContentsCounter::slotDirWatchDirty(const QString& path)
 135 {
 136     const int index = m_model->index(QUrl::fromLocalFile(path));
 137     if (index >= 0) {
 138         if (!m_model->fileItem(index).isDir()) {
 139             // If INotify is used, KDirWatch issues the dirty() signal
 140             // also for changed files inside the directory, even if we
 141             // don't enable this behavior explicitly (see bug 309740).
 142             return;
 143         }
 144
 145         startWorker(path);
 146     }
 147 }
 148
 149 void KDirectoryContentsCounter::slotItemsRemoved()
 150 {
 151     const bool allItemsRemoved = (m_model->count() == 0);
 152
 153     if (!m_watchedDirs.isEmpty()) {
 154         // Don't let KDirWatch watch for removed items
 155         if (allItemsRemoved) {
 156             for (const QString& path : qAsConst(m_watchedDirs)) {
 157                 m_dirWatcher->removeDir(path);
 158             }
 159             m_watchedDirs.clear();
 160             m_queue.clear();
 161         } else {
 162             QMutableSetIterator<QString> it(m_watchedDirs);
 163             while (it.hasNext()) {
 164                 const QString& path = it.next();
 165                 if (m_model->index(QUrl::fromLocalFile(path)) < 0) {
 166                     m_dirWatcher->removeDir(path);
 167                     it.remove();
 168                 }
 169             }
 170         }
 171     }
 172 }
 173
 174 void KDirectoryContentsCounter::startWorker(const QString& path)
 175 {
 176     const bool alreadyInCache = s_cache->contains(path);
 177     if (alreadyInCache) {
 178         // fast path when in cache
 179         // will be updated later if result has changed
 180         const auto pair = s_cache->value(path);
 181         emit result(path, pair.first, pair.second);
 182     }
 183
 184     if (m_workerIsBusy) {
 185         if (std::find(m_queue.begin(), m_queue.end(), path) == m_queue.end() &&
 186             std::find(m_priorityQueue.begin(), m_priorityQueue.end(), path) == m_priorityQueue.end()) {
 187             if (alreadyInCache) {
 188                 m_queue.push_back(path);
 189             } else {
 190                 // append to priority queue
 191                 m_priorityQueue.push_back(path);
 192             }
 193         }
 194     } else {
 195         KDirectoryContentsCounterWorker::Options options;
 196
 197         if (m_model->showHiddenFiles()) {
 198             options |= KDirectoryContentsCounterWorker::CountHiddenFiles;
 199         }
 200
 201         if (m_model->showDirectoriesOnly()) {
 202             options |= KDirectoryContentsCounterWorker::CountDirectoriesOnly;
 203         }
 204
 205         emit requestDirectoryContentsCount(path, options);
 206         m_workerIsBusy = true;
 207     }
 208 }
 209
 210 QThread* KDirectoryContentsCounter::m_workerThread = nullptr;