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** this package.

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** General Public License version 2.1 as published by the Free Software

** Foundation and appearing in the file LICENSE.LGPL included in the

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****************************************************************************/

#ifndef QHOSTINFO_P_H

#define QHOSTINFO_P_H

//

//  W A R N I N G

//  -------------

//

// This file is not part of the Qt API.  It exists for the convenience

// of the QHostInfo class.  This header file may change from

// version to version without notice, or even be removed.

//

// We mean it.

//

#include "QtCore/qcoreapplication.h"

#include "private/qcoreapplication_p.h"

#include "QtNetwork/qhostinfo.h"

#include "QtCore/qmutex.h"

#include "QtCore/qwaitcondition.h"

#include "QtCore/qobject.h"

#include "QtCore/qpointer.h"

#ifndef QT_NO_THREAD

#include "QtCore/qthread.h"

#include "QtCore/qthreadpool.h"

#include "QtCore/qmutex.h"

#include "QtCore/qrunnable.h"

#include "QtCore/qlist.h"

#include "QtCore/qqueue.h"

#include <QTime>

#include <QCache>

#endif

QT_BEGIN_NAMESPACE

class QHostInfoResult : public QObject

{

    Q_OBJECT

public Q_SLOTS:

    inline void emitResultsReady(const QHostInfo &info)

    {

        emit resultsReady(info);

    }

Q_SIGNALS:

    void resultsReady(const QHostInfo info);

};

// needs to be QObject because fromName calls tr()

class QHostInfoAgent : public QObject

{

    Q_OBJECT

public:

    static QHostInfo fromName(const QString &hostName);

};

class QHostInfoPrivate

{

public:

    inline QHostInfoPrivate()

        : err(QHostInfo::NoError),

          errorStr(QLatin1String(QT_TRANSLATE_NOOP("QHostInfo", "Unknown error"))),

          lookupId(0)

    {

    }

    QHostInfo::HostInfoError err;

    QString errorStr;

    QList<QHostAddress> addrs;

    QString hostName;

    int lookupId;

};

#ifndef QT_NO_THREAD

// These functions are outside of the QHostInfo class and strictly internal.

// Do NOT use them outside of QAbstractSocket.

QHostInfo Q_NETWORK_EXPORT qt_qhostinfo_lookup(const QString &name, QObject *receiver, const char *member, bool *valid, int *id);

void Q_NETWORK_EXPORT qt_qhostinfo_clear_cache();

void Q_AUTOTEST_EXPORT qt_qhostinfo_enable_cache(bool e);

class QHostInfoCache

{

public:

    QHostInfoCache();

    const int max_age; // seconds

    QHostInfo get(const QString &name, bool *valid);

    void put(const QString &name, const QHostInfo &info);

    void clear();

    bool isEnabled();

    void setEnabled(bool e);

private:

    bool enabled;

    struct QHostInfoCacheElement {

        QHostInfo info;

        QTime age;

    };

    QCache<QString,QHostInfoCacheElement> cache;

    QMutex mutex;

};

// the following classes are used for the (normal) case: We use multiple threads to lookup DNS

class QHostInfoRunnable : public QRunnable

{

public:

    QHostInfoRunnable (QString hn, int i);

    void run();

    QString toBeLookedUp;

    int id;

    QHostInfoResult resultEmitter;

};

class QHostInfoLookupManager : public QObject

{

    Q_OBJECT

public:

    QHostInfoLookupManager();

    ~QHostInfoLookupManager();

    void work();

    // called from QHostInfo

    void scheduleLookup(QHostInfoRunnable *r);

    void abortLookup(int id);

    // called from QHostInfoRunnable

    void lookupFinished(QHostInfoRunnable *r);

    bool wasAborted(int id);

    QHostInfoCache cache;

protected:

    QList<QHostInfoRunnable*> currentLookups; // in progress

    QList<QHostInfoRunnable*> postponedLookups; // postponed because in progress for same host

    QQueue<QHostInfoRunnable*> scheduledLookups; // not yet started

    QList<QHostInfoRunnable*> finishedLookups; // recently finished

    QList<int> abortedLookups; // ids of aborted lookups

    QThreadPool threadPool;

    QMutex mutex;

    bool wasDeleted;

private slots:

    void waitForThreadPoolDone() { threadPool.waitForDone(); }

};

#endif

QT_END_NAMESPACE

#endif // QHOSTINFO_P_H