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#include "quuid.h"

#include "qdatastream.h"

QT_BEGIN_NAMESPACE

/*!

    \class QUuid

    \brief The QUuid class stores a Universally Unique Identifier (UUID).

    \reentrant

    Using \e{U}niversally \e{U}nique \e{ID}entifiers (UUID) is a

    standard way to uniquely identify entities in a distributed

    computing environment. A UUID is a 16-byte (128-bit) number

    generated by some algorithm that is meant to guarantee that the

    UUID will be unique in the distributed computing environment where

    it is used. The acronym GUID is often used instead, \e{G}lobally

    \e{U}nique \e{ID}entifiers, but it refers to the same thing.

    \target Variant field

    Actually, the GUID is one \e{variant} of UUID. Multiple variants

    are in use. Each UUID contains a bit field that specifies which

    type (variant) of UUID it is. Call variant() to discover which

    type of UUID an instance of QUuid contains. It extracts the three

    most signifcant bits of byte 8 of the 16 bytes. In QUuid, byte 8

    is \c{QUuid::data4[0]}. If you create instances of QUuid using the

    constructor that accepts all the numeric values as parameters, use

    the following table to set the three most significant bits of

    parameter \c{b1}, which becomes \c{QUuid::data4[0]} and contains

    the variant field in its three most significant bits. In the

    table, 'x' means \e {don't care}.

    \table

    \header

    \o msb0

    \o msb1

    \o msb2

    \o Variant 

    \row

    \o 0

    \o x

    \o x

    \o NCS (Network Computing System)

    \row

    \o 1

    \o 0

    \o x

    \o DCE (Distributed Computing Environment)

    \row

    \o 1

    \o 1

    \o 0

    \o Microsoft (GUID)

    \row

    \o 1

    \o 1

    \o 1

    \o Reserved for future expansion

    \endtable

    \target Version field

    If variant() returns QUuid::DCE, the UUID also contains a

    \e{version} field in the four most significant bits of

    \c{QUuid::data3}, and you can call version() to discover which

    version your QUuid contains. If you create instances of QUuid

    using the constructor that accepts all the numeric values as

    parameters, use the following table to set the four most

    significant bits of parameter \c{w2}, which becomes

    \c{QUuid::data3} and contains the version field in its four most

    significant bits.

    \table

    \header

    \o msb0

    \o msb1

    \o msb2

    \o msb3

    \o Version

    \row

    \o 0

    \o 0

    \o 0

    \o 1

    \o Time

    \row

    \o 0

    \o 0

    \o 1

    \o 0

    \o Embedded POSIX

    \row

    \o 0

    \o 0

    \o 1

    \o 1

    \o Name

    \row

    \o 0

    \o 1

    \o 0

    \o 0

    \o Random

    \endtable

    The field layouts for the DCE versions listed in the table above

    are specified in the \l{http://www.ietf.org/rfc/rfc4122.txt}

    {Network Working Group UUID Specification}.

    Most platforms provide a tool for generating new UUIDs, e.g. \c

    uuidgen and \c guidgen. You can also use createUuid().  UUIDs

    generated by createUuid() are of the random type.  Their

    QUuid::Version bits are set to QUuid::Random, and their

    QUuid::Variant bits are set to QUuid::DCE. The rest of the UUID is

    composed of random numbers. Theoretically, this means there is a

    small chance that a UUID generated by createUuid() will not be

    unique. But it is

    \l{http://en.wikipedia.org/wiki/Universally_Unique_Identifier#Random_UUID_probability_of_duplicates}

    {a \e{very} small chance}.

    UUIDs can be constructed from numeric values or from strings, or

    using the static createUuid() function. They can be converted to a

    string with toString(). UUIDs have a variant() and a version(),

    and null UUIDs return true from isNull().

*/

/*!

    \fn QUuid::QUuid(const GUID &guid)

    Casts a Windows \a guid to a Qt QUuid.

    \warning This function is only for Windows platforms.

*/

/*!

    \fn QUuid &QUuid::operator=(const GUID &guid)

    Assigns a Windows \a guid to a Qt QUuid.

    \warning This function is only for Windows platforms.

*/

/*!

    \fn QUuid::operator GUID() const

    Returns a Windows GUID from a QUuid.

    \warning This function is only for Windows platforms.

*/

/*!

    \fn QUuid::QUuid()

    Creates the null UUID. toString() will output the null UUID

    as "{00000000-0000-0000-0000-000000000000}".

*/

/*!

    \fn QUuid::QUuid(uint l, ushort w1, ushort w2, uchar b1, uchar b2, uchar b3, uchar b4, uchar b5, uchar b6, uchar b7, uchar b8)

    Creates a UUID with the value specified by the parameters, \a l,

    \a w1, \a w2, \a b1, \a b2, \a b3, \a b4, \a b5, \a b6, \a b7, \a

    b8.

    Example:

    \snippet doc/src/snippets/code/src_corelib_plugin_quuid.cpp 0

*/

#ifndef QT_NO_QUUID_STRING

/*!

  Creates a QUuid object from the string \a text, which must be

  formatted as five hex fields separated by '-', e.g.,

  "{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}" where 'x' is a hex

  digit. The curly braces shown here are optional, but it is normal to

  include them. If the conversion fails, a null UUID is created.  See

  toString() for an explanation of how the five hex fields map to the

  public data members in QUuid.

    \sa toString(), QUuid()

*/

QUuid::QUuid(const QString &text)

{

    bool ok;

    if (text.isEmpty()) {

        *this = QUuid();

        return;

    }

    QString temp = text.toUpper();

    if (temp[0] != QLatin1Char('{'))

        temp = QLatin1Char('{') + text;

    if (text[(int)text.length()-1] != QLatin1Char('}'))

        temp += QLatin1Char('}');

    data1 = temp.mid(1, 8).toULongLong(&ok, 16);

    if (!ok) {

        *this = QUuid();

        return;

    }

    data2 = temp.mid(10, 4).toUInt(&ok, 16);

    if (!ok) {

        *this = QUuid();

        return;

    }

    data3 = temp.mid(15, 4).toUInt(&ok, 16);

    if (!ok) {

        *this = QUuid();

        return;

    }

    data4[0] = temp.mid(20, 2).toUInt(&ok, 16);

    if (!ok) {

        *this = QUuid();

        return;

    }

    data4[1] = temp.mid(22, 2).toUInt(&ok, 16);

    if (!ok) {

        *this = QUuid();

        return;

    }

    for (int i = 2; i<8; i++) {

        data4[i] = temp.mid(25 + (i-2)*2, 2).toUShort(&ok, 16);

        if (!ok) {

            *this = QUuid();

            return;

        }

    }

}

/*!

    \internal

*/

QUuid::QUuid(const char *text)

{

    *this = QUuid(QString::fromLatin1(text));

}

#endif

/*!

    \fn bool QUuid::operator==(const QUuid &other) const

    Returns true if this QUuid and the \a other QUuid are identical;

    otherwise returns false.

*/

/*!

    \fn bool QUuid::operator!=(const QUuid &other) const

    Returns true if this QUuid and the \a other QUuid are different;

    otherwise returns false.

*/

#ifndef QT_NO_QUUID_STRING

/*!

    \fn QUuid::operator QString() const

    Returns the string representation of the uuid.

    \sa toString()

*/

static QString uuidhex(uint data, int digits)

{

    return QString::number(data, 16).rightJustified(digits, QLatin1Char('0'));

}

/*!

    Returns the string representation of this QUuid. The string is

    formatted as five hex fields separated by '-' and enclosed in

    curly braces, i.e., "{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}" where

    'x' is a hex digit.  From left to right, the five hex fields are

    obtained from the four public data members in QUuid as follows:

    \table

    \header

    \o Field #

    \o Source

    \row

    \o 1

    \o data1

    \row

    \o 2

    \o data2

    \row

    \o 3

    \o data3

    \row

    \o 4

    \o data4[0] .. data4[1]

    \row

    \o 5

    \o data4[2] .. data4[7]

    \endtable

*/

QString QUuid::toString() const

{

    QString result;

    QChar dash = QLatin1Char('-');

    result = QLatin1Char('{') + uuidhex(data1,8);

    result += dash;

    result += uuidhex(data2,4);

    result += dash;

    result += uuidhex(data3,4);

    result += dash;

    result += uuidhex(data4[0],2);

    result += uuidhex(data4[1],2);

    result += dash;

    for (int i = 2; i < 8; i++)

        result += uuidhex(data4[i],2);

    return result + QLatin1Char('}');

}

#endif

#ifndef QT_NO_DATASTREAM

/*!

    \relates QUuid

    Writes the UUID \a id to the data stream \a s.

*/

QDataStream &operator<<(QDataStream &s, const QUuid &id)

{

    s << (quint32)id.data1;

    s << (quint16)id.data2;

    s << (quint16)id.data3;

    for (int i = 0; i < 8; i++)

        s << (quint8)id.data4[i];

    return s;

}

/*!

    \relates QUuid

    Reads a UUID from the stream \a s into \a id.

*/

QDataStream &operator>>(QDataStream &s, QUuid &id)

{

    quint32 u32;

    quint16 u16;

    quint8 u8;

    s >> u32;

    id.data1 = u32;

    s >> u16;

    id.data2 = u16;

    s >> u16;

    id.data3 = u16;

    for (int i = 0; i < 8; i++) {

        s >> u8;

        id.data4[i] = u8;

    }

    return s;

}

#endif // QT_NO_DATASTREAM

/*!

    Returns true if this is the null UUID

    {00000000-0000-0000-0000-000000000000}; otherwise returns false.

*/

bool QUuid::isNull() const

{

    return data4[0] == 0 && data4[1] == 0 && data4[2] == 0 && data4[3] == 0 &&

           data4[4] == 0 && data4[5] == 0 && data4[6] == 0 && data4[7] == 0 &&

           data1 == 0 && data2 == 0 && data3 == 0;

}

/*!

    \enum QUuid::Variant

    This enum defines the values used in the \l{Variant field}

    {variant field} of the UUID. The value in the variant field

    determines the layout of the 128-bit value.

    \value VarUnknown Variant is unknown

    \value NCS Reserved for NCS (Network Computing System) backward compatibility

    \value DCE Distributed Computing Environment, the scheme used by QUuid

    \value Microsoft Reserved for Microsoft backward compatibility (GUID)

    \value Reserved Reserved for future definition

*/

/*!

    \enum QUuid::Version

    This enum defines the values used in the \l{Version field}

    {version field} of the UUID. The version field is meaningful

    only if the value in the \l{Variant field} {variant field}

    is QUuid::DCE.

    \value VerUnknown Version is unknown

    \value Time Time-based, by using timestamp, clock sequence, and

    MAC network card address (if available) for the node sections

    \value EmbeddedPOSIX DCE Security version, with embedded POSIX UUIDs

    \value Name Name-based, by using values from a name for all sections

    \value Random Random-based, by using random numbers for all sections

*/

/*!

    \fn QUuid::Variant QUuid::variant() const

    Returns the value in the \l{Variant field} {variant field} of the

    UUID. If the return value is QUuid::DCE, call version() to see

    which layout it uses. The null UUID is considered to be of an

    unknown variant.

    \sa version()

*/

QUuid::Variant QUuid::variant() const

{

    if (isNull())

        return VarUnknown;

    // Check the 3 MSB of data4[0]

    if ((data4[0] & 0x80) == 0x00) return NCS;

    else if ((data4[0] & 0xC0) == 0x80) return DCE;

    else if ((data4[0] & 0xE0) == 0xC0) return Microsoft;

    else if ((data4[0] & 0xE0) == 0xE0) return Reserved;

    return VarUnknown;

}

/*!

    \fn QUuid::Version QUuid::version() const

    Returns the \l{Version field} {version field} of the UUID, if the

    UUID's \l{Variant field} {variant field} is QUuid::DCE. Otherwise

    it returns QUuid::VerUnknown.

    \sa variant()

*/

QUuid::Version QUuid::version() const

{

    // Check the 4 MSB of data3

    Version ver = (Version)(data3>>12);

    if (isNull()

         || (variant() != DCE)

         || ver < Time

         || ver > Random)

        return VerUnknown;

    return ver;

}

/*!

    \fn bool QUuid::operator<(const QUuid &other) const

    Returns true if this QUuid has the same \l{Variant field}

    {variant field} as the \a other QUuid and is lexicographically

    \e{before} the \a other QUuid. If the \a other QUuid has a

    different variant field, the return value is determined by

    comparing the two \l{QUuid::Variant} {variants}.

    \sa variant()

*/

#define ISLESS(f1, f2) if (f1!=f2) return (f1<f2);

bool QUuid::operator<(const QUuid &other) const

{

    if (variant() != other.variant())

        return variant() < other.variant();

    ISLESS(data1, other.data1);

    ISLESS(data2, other.data2);

    ISLESS(data3, other.data3);

    for (int n = 0; n < 8; n++) {

        ISLESS(data4[n], other.data4[n]);

    }

    return false;

}

/*!

    \fn bool QUuid::operator>(const QUuid &other) const

    Returns true if this QUuid has the same \l{Variant field}

    {variant field} as the \a other QUuid and is lexicographically

    \e{after} the \a other QUuid. If the \a other QUuid has a

    different variant field, the return value is determined by

    comparing the two \l{QUuid::Variant} {variants}.

    \sa variant()