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    41 

    42 #ifndef QLOCK_P_H

    43 #define QLOCK_P_H

    44 

    45 //

    46 //  W A R N I N G

    47 //  -------------

    48 //

    49 // This file is not part of the Qt API.  This header file may

    50 // change from version to version without notice, or even be

    51 // removed.

    52 //

    53 // We mean it.

    54 //

    55 

    56 #include "QtCore/qstring.h"

    57 

    58 QT_BEGIN_NAMESPACE

    59 

    60 class QLockData;

    61 

    62 class Q_GUI_EXPORT QLock

    63 {

    64 public:

    65     QLock(const QString &filename, char id, bool create = false);

    66     ~QLock();

    67 

    68     enum Type { Read, Write };

    69 

    70     bool isValid() const;

    71     void lock(Type type);

    72     void unlock();

    73     bool locked() const;

    74 

    75 private:

    76     Type type;

    77     QLockData *data;

    78 };

    79 

    80 

    81 // Nice class for ensuring the lock is released.

    82 // Just create one on the stack and the lock is automatically released

    83 // when QLockHandle is destructed.

    84 class Q_GUI_EXPORT QLockHandle

    85 {

    86 public:

    87     QLockHandle(QLock *l, QLock::Type type) : qlock(l) { qlock->lock(type); }

    88     ~QLockHandle() { if (locked()) qlock->unlock(); }

    89 

    90     void lock(QLock::Type type) { qlock->lock(type); }

    91     void unlock() { qlock->unlock(); }

    92     bool locked() const { return qlock->locked(); }

    93 

    94 private:

    95     QLock *qlock;

    96 };

    97 

    98 QT_END_NAMESPACE

    99 

   100 #endif // QLOCK_P_H