From 38be0d13830efd2d98281c645c3a60afe05ffece Mon Sep 17 00:00:00 2001 From: Qt by Nokia Date: Wed, 27 Apr 2011 12:05:43 +0200 Subject: Initial import from the monolithic Qt. This is the beginning of revision history for this module. If you want to look at revision history older than this, please refer to the Qt Git wiki for how to use Git history grafting. At the time of writing, this wiki is located here: http://qt.gitorious.org/qt/pages/GitIntroductionWithQt If you have already performed the grafting and you don't see any history beyond this commit, try running "git log" with the "--follow" argument. Branched from the monolithic repo, Qt master branch, at commit 896db169ea224deb96c59ce8af800d019de63f12 --- src/corelib/plugin/quuid.cpp | 676 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 676 insertions(+) create mode 100644 src/corelib/plugin/quuid.cpp (limited to 'src/corelib/plugin/quuid.cpp') diff --git a/src/corelib/plugin/quuid.cpp b/src/corelib/plugin/quuid.cpp new file mode 100644 index 0000000000..ba47beccb2 --- /dev/null +++ b/src/corelib/plugin/quuid.cpp @@ -0,0 +1,676 @@ +/**************************************************************************** +** +** 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. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the Technology Preview License Agreement accompanying +** this package. +** +** GNU Lesser General Public License Usage +** Alternatively, 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. +** +** If you have questions regarding the use of this file, please contact +** Nokia at qt-info@nokia.com. +** +** +** +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#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(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 // 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 // for RAND_MAX +QT_END_INCLUDE_NAMESPACE + +#if !defined(QT_BOOTSTRAPPED) && defined(Q_OS_UNIX) +Q_GLOBAL_STATIC(QThreadStorage, 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 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()<