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#ifndef QBITFIELD_P_H

#define QBITFIELD_P_H

//

//  W A R N I N G

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

//

// This file is not part of the Qt API.  It exists purely as an

// implementation detail.  This header file may change from version to

// version without notice, or even be removed.

//

// We mean it.

//

#include <QtCore/qglobal.h>

QT_BEGIN_NAMESPACE

class QBitField

{

public:

    inline QBitField();

    inline QBitField(const quint32 *, int bits);

    inline QBitField(const QBitField &);

    inline ~QBitField();

    inline QBitField &operator=(const QBitField &);

    inline quint32 size() const;

    inline QBitField united(const QBitField &);

    inline bool testBit(int) const;

private:

    quint32 bits:31;

    quint32 *ownData;

    const quint32 *data;

};

QBitField::QBitField()

: bits(0), ownData(0), data(0)

{

}

QBitField::QBitField(const quint32 *bitData, int bitCount)

: bits((quint32)bitCount), ownData(0), data(bitData)

{

}

QBitField::QBitField(const QBitField &other)

: bits(other.bits), ownData(other.ownData), data(other.data)

{

    if (ownData) 

        ++(*ownData);

}

QBitField::~QBitField()

{

    if (ownData) 

        if(0 == --(*ownData)) delete [] ownData;

}

QBitField &QBitField::operator=(const QBitField &other)

{

    if (other.data == data)

        return *this;

    if (ownData) 

        if(0 == --(*ownData)) delete [] ownData;

    bits = other.bits;

    ownData = other.ownData;

    data = other.data;

    if (ownData) 

        ++(*ownData);

    return *this;

}

inline quint32 QBitField::size() const

{

    return bits;

}

QBitField QBitField::united(const QBitField &o)

{

    if (o.bits == 0) {

        return *this;

    } else if (bits == 0) {

        return o;

    } else {

        int max = (bits > o.bits)?bits:o.bits;

        int length = (max + 31) / 32;

        QBitField rv;

        rv.bits = max;

        rv.ownData = new quint32[length + 1];

        *(rv.ownData) = 1;

        rv.data = rv.ownData + 1;

        if (bits > o.bits) {

            ::memcpy((quint32 *)rv.data, data, length * sizeof(quint32));

            for (quint32 ii = 0; ii < (o.bits + quint32(31)) / 32; ++ii)

                ((quint32 *)rv.data)[ii] |= o.data[ii];

        } else {

            ::memcpy((quint32 *)rv.data, o.data, length * sizeof(quint32));

            for (quint32 ii = 0; ii < (bits + quint32(31)) / 32; ++ii)

                ((quint32 *)rv.data)[ii] |= data[ii];

        }

        return rv;

    }

}

bool QBitField::testBit(int b) const

{

    Q_ASSERT(b >= 0);

    if ((quint32)b < bits) {

        return data[b / 32] & (1 << (b % 32));

    } else {

        return false;

    }

}

QT_END_NAMESPACE

#endif // QBITFIELD_P_H