/**************************************************************************** | |
** | |
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). | |
** All rights reserved. | |
** Contact: Nokia Corporation (qt-info@nokia.com) | |
** | |
** This file is part of the QtCore module of the Qt Toolkit. | |
** | |
** $QT_BEGIN_LICENSE:LGPL$ | |
** GNU Lesser General Public License Usage | |
** This file may be used under the terms of the GNU Lesser General Public | |
** License version 2.1 as published by the Free Software Foundation and | |
** appearing in the file LICENSE.LGPL included in the packaging of this | |
** file. Please review the following information to ensure the GNU Lesser | |
** General Public License version 2.1 requirements will be met: | |
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. | |
** | |
** In addition, as a special exception, Nokia gives you certain additional | |
** rights. These rights are described in the Nokia Qt LGPL Exception | |
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. | |
** | |
** GNU General Public License Usage | |
** Alternatively, this file may be used under the terms of the GNU General | |
** Public License version 3.0 as published by the Free Software Foundation | |
** and appearing in the file LICENSE.GPL included in the packaging of this | |
** file. Please review the following information to ensure the GNU General | |
** Public License version 3.0 requirements will be met: | |
** http://www.gnu.org/copyleft/gpl.html. | |
** | |
** Other Usage | |
** Alternatively, this file may be used in accordance with the terms and | |
** conditions contained in a signed written agreement between you and Nokia. | |
** | |
** | |
** | |
** | |
** | |
** $QT_END_LICENSE$ | |
** | |
****************************************************************************/ | |
#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() | |
*/ | |
#define ISMORE(f1, f2) if (f1!=f2) return (f1>f2); | |
bool QUuid::operator>(const QUuid &other) const | |
{ | |
if (variant() != other.variant()) | |
return variant() > other.variant(); | |
ISMORE(data1, other.data1); | |
ISMORE(data2, other.data2); | |
ISMORE(data3, other.data3); | |
for (int n = 0; n < 8; n++) { | |
ISMORE(data4[n], other.data4[n]); | |
} | |
return false; | |
} | |
/*! | |
\fn QUuid QUuid::createUuid() | |
On any platform other than Windows, this function returns a new | |
UUID with variant QUuid::DCE and version QUuid::Random. If | |
the /dev/urandom device exists, then the numbers used to construct | |
the UUID will be of cryptographic quality, which will make the UUID | |
unique. Otherwise, the numbers of the UUID will be obtained from | |
the local pseudo-random number generator (qrand(), which is seeded | |
by qsrand()) which is usually not of cryptograhic quality, which | |
means that the UUID can't be guaranteed to be unique. | |
On a Windows platform, a GUID is generated, which almost certainly | |
\e{will} be unique, on this or any other system, networked or not. | |
\sa variant(), version() | |
*/ | |
#if defined(Q_OS_WIN32) && ! defined(Q_CC_MWERKS) | |
QT_BEGIN_INCLUDE_NAMESPACE | |
#include <objbase.h> // For CoCreateGuid | |
QT_END_INCLUDE_NAMESPACE | |
QUuid QUuid::createUuid() | |
{ | |
GUID guid; | |
CoCreateGuid(&guid); | |
QUuid result = guid; | |
return result; | |
} | |
#else // !Q_OS_WIN32 | |
QT_BEGIN_INCLUDE_NAMESPACE | |
#include "qdatetime.h" | |
#include "qfile.h" | |
#include "qthreadstorage.h" | |
#include <stdlib.h> // for RAND_MAX | |
QT_END_INCLUDE_NAMESPACE | |
#if !defined(QT_BOOTSTRAPPED) && defined(Q_OS_UNIX) | |
Q_GLOBAL_STATIC(QThreadStorage<QFile *>, devUrandomStorage); | |
#endif | |
QUuid QUuid::createUuid() | |
{ | |
QUuid result; | |
uint *data = &(result.data1); | |
#if defined(Q_OS_UNIX) | |
QFile *devUrandom; | |
# if !defined(QT_BOOTSTRAPPED) | |
devUrandom = devUrandomStorage()->localData(); | |
if (!devUrandom) { | |
devUrandom = new QFile(QLatin1String("/dev/urandom")); | |
devUrandom->open(QIODevice::ReadOnly | QIODevice::Unbuffered); | |
devUrandomStorage()->setLocalData(devUrandom); | |
} | |
# else | |
QFile file(QLatin1String("/dev/urandom")); | |
devUrandom = &file; | |
devUrandom->open(QIODevice::ReadOnly | QIODevice::Unbuffered); | |
# endif | |
enum { AmountToRead = 4 * sizeof(uint) }; | |
if (devUrandom->isOpen() | |
&& devUrandom->read((char *) data, AmountToRead) == AmountToRead) { | |
// we got what we wanted, nothing more to do | |
; | |
} else | |
#endif | |
{ | |
static const int intbits = sizeof(int)*8; | |
static int randbits = 0; | |
if (!randbits) { | |
int r = 0; | |
int max = RAND_MAX; | |
do { ++r; } while ((max=max>>1)); | |
randbits = r; | |
} | |
// Seed the PRNG once per thread with a combination of current time, a | |
// stack address and a serial counter (since thread stack addresses are | |
// re-used). | |
#ifndef QT_BOOTSTRAPPED | |
static QThreadStorage<int *> uuidseed; | |
if (!uuidseed.hasLocalData()) | |
{ | |
int *pseed = new int; | |
static QBasicAtomicInt serial = Q_BASIC_ATOMIC_INITIALIZER(2); | |
qsrand(*pseed = QDateTime::currentDateTime().toTime_t() | |
+ quintptr(&pseed) | |
+ serial.fetchAndAddRelaxed(1)); | |
uuidseed.setLocalData(pseed); | |
} | |
#else | |
static bool seeded = false; | |
if (!seeded) | |
qsrand(QDateTime::currentDateTime().toTime_t() | |
+ quintptr(&seeded)); | |
#endif | |
int chunks = 16 / sizeof(uint); | |
while (chunks--) { | |
uint randNumber = 0; | |
for (int filled = 0; filled < intbits; filled += randbits) | |
randNumber |= qrand()<<filled; | |
*(data+chunks) = randNumber; | |
} | |
} | |
result.data4[0] = (result.data4[0] & 0x3F) | 0x80; // UV_DCE | |
result.data3 = (result.data3 & 0x0FFF) | 0x4000; // UV_Random | |
return result; | |
} | |
#endif // !Q_OS_WIN32 | |
/*! | |
\fn bool QUuid::operator==(const GUID &guid) const | |
Returns true if this UUID is equal to the Windows GUID \a guid; | |
otherwise returns false. | |
*/ | |
/*! | |
\fn bool QUuid::operator!=(const GUID &guid) const | |
Returns true if this UUID is not equal to the Windows GUID \a | |
guid; otherwise returns false. | |
*/ | |
QT_END_NAMESPACE |