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+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain
+** additional rights. These rights are described in the Nokia Qt LGPL
+** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
+** package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at qt-sales@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qfilesystemwatcher.h"
+#include "qfilesystemwatcher_p.h"
+
+#ifndef QT_NO_FILESYSTEMWATCHER
+
+#include <qdatetime.h>
+#include <qdebug.h>
+#include <qdir.h>
+#include <qfileinfo.h>
+#include <qmutex.h>
+#include <qset.h>
+#include <qtimer.h>
+
+#if defined(Q_OS_WIN)
+# include "qfilesystemwatcher_win_p.h"
+#elif defined(Q_OS_LINUX)
+# include "qfilesystemwatcher_inotify_p.h"
+# include "qfilesystemwatcher_dnotify_p.h"
+#elif defined(Q_OS_FREEBSD) || defined(Q_OS_MAC)
+# include "qfilesystemwatcher_kqueue_p.h"
+#endif
+
+QT_BEGIN_NAMESPACE
+
+enum { PollingInterval = 1000 };
+
+class QPollingFileSystemWatcherEngine : public QFileSystemWatcherEngine
+{
+ Q_OBJECT
+
+ class FileInfo
+ {
+ uint ownerId;
+ uint groupId;
+ QFile::Permissions permissions;
+ QDateTime lastModified;
+ QStringList entries;
+
+ public:
+ FileInfo(const QFileInfo &fileInfo)
+ : ownerId(fileInfo.ownerId()),
+ groupId(fileInfo.groupId()),
+ permissions(fileInfo.permissions()),
+ lastModified(fileInfo.lastModified())
+ {
+ if (fileInfo.isDir()) {
+ entries = fileInfo.absoluteDir().entryList(QDir::AllEntries);
+ }
+ }
+ FileInfo &operator=(const QFileInfo &fileInfo)
+ {
+ *this = FileInfo(fileInfo);
+ return *this;
+ }
+
+ bool operator!=(const QFileInfo &fileInfo) const
+ {
+ if (fileInfo.isDir() && entries != fileInfo.absoluteDir().entryList(QDir::AllEntries))
+ return true;
+ return (ownerId != fileInfo.ownerId()
+ || groupId != fileInfo.groupId()
+ || permissions != fileInfo.permissions()
+ || lastModified != fileInfo.lastModified());
+ }
+ };
+
+ mutable QMutex mutex;
+ QHash<QString, FileInfo> files, directories;
+
+public:
+ QPollingFileSystemWatcherEngine();
+
+ void run();
+
+ QStringList addPaths(const QStringList &paths, QStringList *files, QStringList *directories);
+ QStringList removePaths(const QStringList &paths, QStringList *files, QStringList *directories);
+
+ void stop();
+
+private slots:
+ void timeout();
+};
+
+QPollingFileSystemWatcherEngine::QPollingFileSystemWatcherEngine()
+{
+#ifndef QT_NO_THREAD
+ moveToThread(this);
+#endif
+}
+
+void QPollingFileSystemWatcherEngine::run()
+{
+ QTimer timer;
+ connect(&timer, SIGNAL(timeout()), SLOT(timeout()));
+ timer.start(PollingInterval);
+ (void) exec();
+}
+
+QStringList QPollingFileSystemWatcherEngine::addPaths(const QStringList &paths,
+ QStringList *files,
+ QStringList *directories)
+{
+ QMutexLocker locker(&mutex);
+ QStringList p = paths;
+ QMutableListIterator<QString> it(p);
+ while (it.hasNext()) {
+ QString path = it.next();
+ QFileInfo fi(path);
+ if (!fi.exists())
+ continue;
+ if (fi.isDir()) {
+ if (!directories->contains(path))
+ directories->append(path);
+ if (!path.endsWith(QLatin1Char('/')))
+ fi = QFileInfo(path + QLatin1Char('/'));
+ this->directories.insert(path, fi);
+ } else {
+ if (!files->contains(path))
+ files->append(path);
+ this->files.insert(path, fi);
+ }
+ it.remove();
+ }
+ start();
+ return p;
+}
+
+QStringList QPollingFileSystemWatcherEngine::removePaths(const QStringList &paths,
+ QStringList *files,
+ QStringList *directories)
+{
+ QMutexLocker locker(&mutex);
+ QStringList p = paths;
+ QMutableListIterator<QString> it(p);
+ while (it.hasNext()) {
+ QString path = it.next();
+ if (this->directories.remove(path)) {
+ directories->removeAll(path);
+ it.remove();
+ } else if (this->files.remove(path)) {
+ files->removeAll(path);
+ it.remove();
+ }
+ }
+ if (this->files.isEmpty() && this->directories.isEmpty()) {
+ locker.unlock();
+ stop();
+ wait();
+ }
+ return p;
+}
+
+void QPollingFileSystemWatcherEngine::stop()
+{
+ QMetaObject::invokeMethod(this, "quit");
+}
+
+void QPollingFileSystemWatcherEngine::timeout()
+{
+ QMutexLocker locker(&mutex);
+ QMutableHashIterator<QString, FileInfo> fit(files);
+ while (fit.hasNext()) {
+ QHash<QString, FileInfo>::iterator x = fit.next();
+ QString path = x.key();
+ QFileInfo fi(path);
+ if (!fi.exists()) {
+ fit.remove();
+ emit fileChanged(path, true);
+ } else if (x.value() != fi) {
+ x.value() = fi;
+ emit fileChanged(path, false);
+ }
+ }
+ QMutableHashIterator<QString, FileInfo> dit(directories);
+ while (dit.hasNext()) {
+ QHash<QString, FileInfo>::iterator x = dit.next();
+ QString path = x.key();
+ QFileInfo fi(path);
+ if (!path.endsWith(QLatin1Char('/')))
+ fi = QFileInfo(path + QLatin1Char('/'));
+ if (!fi.exists()) {
+ dit.remove();
+ emit directoryChanged(path, true);
+ } else if (x.value() != fi) {
+ x.value() = fi;
+ emit directoryChanged(path, false);
+ }
+
+ }
+}
+
+
+
+
+QFileSystemWatcherEngine *QFileSystemWatcherPrivate::createNativeEngine()
+{
+#if defined(Q_OS_WIN)
+ return new QWindowsFileSystemWatcherEngine;
+#elif defined(Q_OS_LINUX)
+ QFileSystemWatcherEngine *eng = QInotifyFileSystemWatcherEngine::create();
+ if(!eng)
+ eng = QDnotifyFileSystemWatcherEngine::create();
+ return eng;
+#elif defined(Q_OS_FREEBSD) || defined(Q_OS_MAC)
+ return QKqueueFileSystemWatcherEngine::create();
+#else
+ return 0;
+#endif
+}
+
+QFileSystemWatcherPrivate::QFileSystemWatcherPrivate()
+ : native(0), poller(0), forced(0)
+{
+}
+
+void QFileSystemWatcherPrivate::init()
+{
+ Q_Q(QFileSystemWatcher);
+ native = createNativeEngine();
+ if (native) {
+ QObject::connect(native,
+ SIGNAL(fileChanged(QString,bool)),
+ q,
+ SLOT(_q_fileChanged(QString,bool)));
+ QObject::connect(native,
+ SIGNAL(directoryChanged(QString,bool)),
+ q,
+ SLOT(_q_directoryChanged(QString,bool)));
+ }
+}
+
+void QFileSystemWatcherPrivate::initForcedEngine(const QString &forceName)
+{
+ if(forced)
+ return;
+
+ Q_Q(QFileSystemWatcher);
+
+#if defined(Q_OS_LINUX)
+ if(forceName == QLatin1String("inotify")) {
+ forced = QInotifyFileSystemWatcherEngine::create();
+ } else if(forceName == QLatin1String("dnotify")) {
+ forced = QDnotifyFileSystemWatcherEngine::create();
+ }
+#else
+ Q_UNUSED(forceName);
+#endif
+
+ if(forced) {
+ QObject::connect(forced,
+ SIGNAL(fileChanged(QString,bool)),
+ q,
+ SLOT(_q_fileChanged(QString,bool)));
+ QObject::connect(forced,
+ SIGNAL(directoryChanged(QString,bool)),
+ q,
+ SLOT(_q_directoryChanged(QString,bool)));
+ }
+}
+
+void QFileSystemWatcherPrivate::initPollerEngine()
+{
+ if(poller)
+ return;
+
+ Q_Q(QFileSystemWatcher);
+ poller = new QPollingFileSystemWatcherEngine; // that was a mouthful
+ QObject::connect(poller,
+ SIGNAL(fileChanged(QString,bool)),
+ q,
+ SLOT(_q_fileChanged(QString,bool)));
+ QObject::connect(poller,
+ SIGNAL(directoryChanged(QString,bool)),
+ q,
+ SLOT(_q_directoryChanged(QString,bool)));
+}
+
+void QFileSystemWatcherPrivate::_q_fileChanged(const QString &path, bool removed)
+{
+ Q_Q(QFileSystemWatcher);
+ if (!files.contains(path)) {
+ // the path was removed after a change was detected, but before we delivered the signal
+ return;
+ }
+ if (removed)
+ files.removeAll(path);
+ emit q->fileChanged(path);
+}
+
+void QFileSystemWatcherPrivate::_q_directoryChanged(const QString &path, bool removed)
+{
+ Q_Q(QFileSystemWatcher);
+ if (!directories.contains(path)) {
+ // perhaps the path was removed after a change was detected, but before we delivered the signal
+ return;
+ }
+ if (removed)
+ directories.removeAll(path);
+ emit q->directoryChanged(path);
+}
+
+
+
+/*!
+ \class QFileSystemWatcher
+ \brief The QFileSystemWatcher class provides an interface for monitoring files and directories for modifications.
+ \ingroup io
+ \since 4.2
+ \reentrant
+
+ QFileSystemWatcher monitors the file system for changes to files
+ and directories by watching a list of specified paths.
+
+ Call addPath() to watch a particular file or directory. Multiple
+ paths can be added using the addPaths() function. Existing paths can
+ be removed by using the removePath() and removePaths() functions.
+
+ QFileSystemWatcher examines each path added to it. Files that have
+ been added to the QFileSystemWatcher can be accessed using the
+ files() function, and directories using the directories() function.
+
+ The fileChanged() signal is emitted when a file has been modified,
+ renamed or removed from disk. Similarly, the directoryChanged()
+ signal is emitted when a directory or its contents is modified or
+ removed. Note that QFileSystemWatcher stops monitoring files once
+ they have been renamed or removed from disk, and directories once
+ they have been removed from disk.
+
+ \note On systems running a Linux kernel without inotify support,
+ file systems that contain watched paths cannot be unmounted.
+
+ \note Windows CE does not support directory monitoring by
+ default as this depends on the file system driver installed.
+
+ \note The act of monitoring files and directories for
+ modifications consumes system resources. This implies there is a
+ limit to the number of files and directories your process can
+ monitor simultaneously. On Mac OS and all BSD variants, for
+ example, an open file descriptor is required for each monitored
+ file. The system limits the number of open file descriptors to 256
+ by default. This means that addPath() and addPaths() will fail if
+ your process tries to add more than 256 files or directories to
+ the file system monitor. Also note that your process may have
+ other file descriptors open in addition to the ones for files
+ being monitored, and these other open descriptors also count in
+ the total.
+
+ \sa QFile, QDir
+*/
+
+
+/*!
+ Constructs a new file system watcher object with the given \a parent.
+*/
+QFileSystemWatcher::QFileSystemWatcher(QObject *parent)
+ : QObject(*new QFileSystemWatcherPrivate, parent)
+{
+ d_func()->init();
+}
+
+/*!
+ Constructs a new file system watcher object with the given \a parent
+ which monitors the specified \a paths list.
+*/
+QFileSystemWatcher::QFileSystemWatcher(const QStringList &paths, QObject *parent)
+ : QObject(*new QFileSystemWatcherPrivate, parent)
+{
+ d_func()->init();
+ addPaths(paths);
+}
+
+/*!
+ Destroys the file system watcher.
+*/
+QFileSystemWatcher::~QFileSystemWatcher()
+{
+ Q_D(QFileSystemWatcher);
+ if (d->native) {
+ d->native->stop();
+ d->native->wait();
+ delete d->native;
+ d->native = 0;
+ }
+ if (d->poller) {
+ d->poller->stop();
+ d->poller->wait();
+ delete d->poller;
+ d->poller = 0;
+ }
+ if (d->forced) {
+ d->forced->stop();
+ d->forced->wait();
+ delete d->forced;
+ d->forced = 0;
+ }
+}
+
+/*!
+ Adds \a path to the file system watcher if \a path exists. The
+ path is not added if it does not exist, or if it is already being
+ monitored by the file system watcher.
+
+ If \a path specifies a directory, the directoryChanged() signal
+ will be emitted when \a path is modified or removed from disk;
+ otherwise the fileChanged() signal is emitted when \a path is
+ modified, renamed or removed.
+
+ \note There is a system dependent limit to the number of files and
+ directories that can be monitored simultaneously. If this limit
+ has been reached, \a path will not be added to the file system
+ watcher, and a warning message will be printed to \e{stderr}.
+
+ \sa addPaths(), removePath()
+*/
+void QFileSystemWatcher::addPath(const QString &path)
+{
+ if (path.isEmpty()) {
+ qWarning("QFileSystemWatcher::addPath: path is empty");
+ return;
+ }
+ addPaths(QStringList(path));
+}
+
+/*!
+ Adds each path in \a paths to the file system watcher. Paths are
+ not added if they not exist, or if they are already being
+ monitored by the file system watcher.
+
+ If a path specifies a directory, the directoryChanged() signal
+ will be emitted when the path is modified or removed from disk;
+ otherwise the fileChanged() signal is emitted when the path is
+ modified, renamed, or removed.
+
+ \note There is a system dependent limit to the number of files and
+ directories that can be monitored simultaneously. If this limit
+ has been reached, the excess \a paths will not be added to the
+ file system watcher, and a warning message will be printed to
+ \e{stderr} for each path that could not be added.
+
+ \sa addPath(), removePaths()
+*/
+void QFileSystemWatcher::addPaths(const QStringList &paths)
+{
+ Q_D(QFileSystemWatcher);
+ if (paths.isEmpty()) {
+ qWarning("QFileSystemWatcher::addPaths: list is empty");
+ return;
+ }
+
+ QStringList p = paths;
+ QFileSystemWatcherEngine *engine = 0;
+
+ if(!objectName().startsWith(QLatin1String("_qt_autotest_force_engine_"))) {
+ // Normal runtime case - search intelligently for best engine
+ if(d->native) {
+ engine = d->native;
+ } else {
+ d_func()->initPollerEngine();
+ engine = d->poller;
+ }
+
+ } else {
+ // Autotest override case - use the explicitly selected engine only
+ QString forceName = objectName().mid(26);
+ if(forceName == QLatin1String("poller")) {
+ qDebug() << "QFileSystemWatcher: skipping native engine, using only polling engine";
+ d_func()->initPollerEngine();
+ engine = d->poller;
+ } else if(forceName == QLatin1String("native")) {
+ qDebug() << "QFileSystemWatcher: skipping polling engine, using only native engine";
+ engine = d->native;
+ } else {
+ qDebug() << "QFileSystemWatcher: skipping polling and native engine, using only explicit" << forceName << "engine";
+ d_func()->initForcedEngine(forceName);
+ engine = d->forced;
+ }
+ }
+
+ if(engine)
+ p = engine->addPaths(p, &d->files, &d->directories);
+
+ if (!p.isEmpty())
+ qWarning("QFileSystemWatcher: failed to add paths: %s",
+ qPrintable(p.join(QLatin1String(", "))));
+}
+
+/*!
+ Removes the specified \a path from the file system watcher.
+
+ \sa removePaths(), addPath()
+*/
+void QFileSystemWatcher::removePath(const QString &path)
+{
+ if (path.isEmpty()) {
+ qWarning("QFileSystemWatcher::removePath: path is empty");
+ return;
+ }
+ removePaths(QStringList(path));
+}
+
+/*!
+ Removes the specified \a paths from the file system watcher.
+
+ \sa removePath(), addPaths()
+*/
+void QFileSystemWatcher::removePaths(const QStringList &paths)
+{
+ if (paths.isEmpty()) {
+ qWarning("QFileSystemWatcher::removePaths: list is empty");
+ return;
+ }
+ Q_D(QFileSystemWatcher);
+ QStringList p = paths;
+ if (d->native)
+ p = d->native->removePaths(p, &d->files, &d->directories);
+ if (d->poller)
+ p = d->poller->removePaths(p, &d->files, &d->directories);
+ if (d->forced)
+ p = d->forced->removePaths(p, &d->files, &d->directories);
+}
+
+/*!
+ \fn void QFileSystemWatcher::fileChanged(const QString &path)
+
+ This signal is emitted when the file at the specified \a path is
+ modified, renamed or removed from disk.
+
+ \sa directoryChanged()
+*/
+
+/*!
+ \fn void QFileSystemWatcher::directoryChanged(const QString &path)
+
+ This signal is emitted when the directory at a specified \a path,
+ is modified (e.g., when a file is added, modified or deleted) or
+ removed from disk. Note that if there are several changes during a
+ short period of time, some of the changes might not emit this
+ signal. However, the last change in the sequence of changes will
+ always generate this signal.
+
+ \sa fileChanged()
+*/
+
+/*!
+ \fn QStringList QFileSystemWatcher::directories() const
+
+ Returns a list of paths to directories that are being watched.
+
+ \sa files()
+*/
+
+/*!
+ \fn QStringList QFileSystemWatcher::files() const
+
+ Returns a list of paths to files that are being watched.
+
+ \sa directories()
+*/
+
+QStringList QFileSystemWatcher::directories() const
+{
+ Q_D(const QFileSystemWatcher);
+ return d->directories;
+}
+
+QStringList QFileSystemWatcher::files() const
+{
+ Q_D(const QFileSystemWatcher);
+ return d->files;
+}
+
+QT_END_NAMESPACE
+
+#include "moc_qfilesystemwatcher.cpp"
+
+#include "qfilesystemwatcher.moc"
+
+#endif // QT_NO_FILESYSTEMWATCHER
+