qfilesystemwatcher.cpp

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#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_QNX) && !defined(QT_NO_INOTIFY)
#  include "qfilesystemwatcher_inotify_p.h"
#elif defined(Q_OS_FREEBSD) || defined(Q_OS_MAC)
#  if (defined Q_OS_MAC) && (MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5)
#  include "qfilesystemwatcher_fsevents_p.h"
#  endif //MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5)
#  include "qfilesystemwatcher_kqueue_p.h"
#elif defined(Q_OS_SYMBIAN)
#  include "qfilesystemwatcher_symbian_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 Q_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()
{
    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) {
            fi.refresh();
            if (!fi.exists()) {
                dit.remove();
                emit directoryChanged(path, true);
            } else {
                x.value() = fi;
                emit directoryChanged(path, false);
            }
        }
        
    }
}




QFileSystemWatcherEngine *QFileSystemWatcherPrivate::createNativeEngine()
{
#if defined(Q_OS_WIN)
    return new QWindowsFileSystemWatcherEngine;
#elif defined(Q_OS_QNX) && !defined(QT_NO_INOTIFY)
    return QInotifyFileSystemWatcherEngine::create();
#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)
#  if 0 && defined(Q_OS_MAC) && (MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5)
    if (QSysInfo::MacintoshVersion >= QSysInfo::MV_10_5)
        return QFSEventsFileSystemWatcherEngine::create();
    else
#  endif
        return QKqueueFileSystemWatcherEngine::create();
#elif defined(Q_OS_SYMBIAN)
    return new QSymbianFileSystemWatcherEngine;
#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);
}



QFileSystemWatcher::QFileSystemWatcher(QObject *parent)
    : QObject(*new QFileSystemWatcherPrivate, parent)
{
    d_func()->init();
}

QFileSystemWatcher::QFileSystemWatcher(const QStringList &paths, QObject *parent)
    : QObject(*new QFileSystemWatcherPrivate, parent)
{
    d_func()->init();
    addPaths(paths);
}

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;
    }
}

void QFileSystemWatcher::addPath(const QString &path)
{
    if (path.isEmpty()) {
        qWarning("QFileSystemWatcher::addPath: path is empty");
        return;
    }
    addPaths(QStringList(path));
}

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(", "))));
}

void QFileSystemWatcher::removePath(const QString &path)
{
    if (path.isEmpty()) {
        qWarning("QFileSystemWatcher::removePath: path is empty");
        return;
    }
    removePaths(QStringList(path));
}

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);
}

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