diff options
Diffstat (limited to 'src/corelib/plugin/quuid.cpp')
| -rw-r--r-- | src/corelib/plugin/quuid.cpp | 215 |
1 files changed, 125 insertions, 90 deletions
diff --git a/src/corelib/plugin/quuid.cpp b/src/corelib/plugin/quuid.cpp index 0afce7fcf0..c9644c73d3 100644 --- a/src/corelib/plugin/quuid.cpp +++ b/src/corelib/plugin/quuid.cpp @@ -1,6 +1,7 @@ /**************************************************************************** ** ** Copyright (C) 2016 The Qt Company Ltd. +** Copyright (C) 2017 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Marc Mutz <marc.mutz@kdab.com> ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the QtCore module of the Qt Toolkit. @@ -49,21 +50,25 @@ #endif QT_BEGIN_NAMESPACE -template <class Char, class Integral> -void _q_toHex(Char *&dst, Integral value) +// 16 bytes (a uint, two shorts and a uchar[8]), each represented by two hex +// digits; plus four dashes and a pair of enclosing brace: 16*2 + 4 + 2 = 38. +enum { MaxStringUuidLength = 38 }; + +template <class Integral> +void _q_toHex(char *&dst, Integral value) { value = qToBigEndian(value); const char* p = reinterpret_cast<const char*>(&value); for (uint i = 0; i < sizeof(Integral); ++i, dst += 2) { - dst[0] = Char(QtMiscUtils::toHexLower((p[i] >> 4) & 0xf)); - dst[1] = Char(QtMiscUtils::toHexLower(p[i] & 0xf)); + dst[0] = QtMiscUtils::toHexLower((p[i] >> 4) & 0xf); + dst[1] = QtMiscUtils::toHexLower(p[i] & 0xf); } } -template <class Char, class Integral> -bool _q_fromHex(const Char *&src, Integral &value) +template <class Integral> +bool _q_fromHex(const char *&src, Integral &value) { value = 0; @@ -79,48 +84,64 @@ bool _q_fromHex(const Char *&src, Integral &value) return true; } -template <class Char> -void _q_uuidToHex(Char *&dst, const uint &d1, const ushort &d2, const ushort &d3, const uchar (&d4)[8]) +static char *_q_uuidToHex(const QUuid &uuid, char *dst) { - *dst++ = Char('{'); - _q_toHex(dst, d1); - *dst++ = Char('-'); - _q_toHex(dst, d2); - *dst++ = Char('-'); - _q_toHex(dst, d3); - *dst++ = Char('-'); + *dst++ = '{'; + _q_toHex(dst, uuid.data1); + *dst++ = '-'; + _q_toHex(dst, uuid.data2); + *dst++ = '-'; + _q_toHex(dst, uuid.data3); + *dst++ = '-'; for (int i = 0; i < 2; i++) - _q_toHex(dst, d4[i]); - *dst++ = Char('-'); + _q_toHex(dst, uuid.data4[i]); + *dst++ = '-'; for (int i = 2; i < 8; i++) - _q_toHex(dst, d4[i]); - *dst = Char('}'); + _q_toHex(dst, uuid.data4[i]); + *dst++ = '}'; + return dst; } -template <class Char> -bool _q_uuidFromHex(const Char *&src, uint &d1, ushort &d2, ushort &d3, uchar (&d4)[8]) +/*! + \internal + + Parses the string representation of a UUID (with optional surrounding "{}") + by reading at most MaxStringUuidLength (38) characters from \a src, which + may be \c nullptr. Stops at the first invalid character (which includes a + premature NUL). + + Returns the successfully parsed QUuid, or a null QUuid in case of failure. +*/ +Q_NEVER_INLINE +static QUuid _q_uuidFromHex(const char *src) { - if (*src == Char('{')) - src++; - if (!_q_fromHex(src, d1) - || *src++ != Char('-') - || !_q_fromHex(src, d2) - || *src++ != Char('-') - || !_q_fromHex(src, d3) - || *src++ != Char('-') - || !_q_fromHex(src, d4[0]) - || !_q_fromHex(src, d4[1]) - || *src++ != Char('-') - || !_q_fromHex(src, d4[2]) - || !_q_fromHex(src, d4[3]) - || !_q_fromHex(src, d4[4]) - || !_q_fromHex(src, d4[5]) - || !_q_fromHex(src, d4[6]) - || !_q_fromHex(src, d4[7])) { - return false; + uint d1; + ushort d2, d3; + uchar d4[8]; + + if (src) { + if (*src == '{') + src++; + if (Q_LIKELY( _q_fromHex(src, d1) + && *src++ == '-' + && _q_fromHex(src, d2) + && *src++ == '-' + && _q_fromHex(src, d3) + && *src++ == '-' + && _q_fromHex(src, d4[0]) + && _q_fromHex(src, d4[1]) + && *src++ == '-' + && _q_fromHex(src, d4[2]) + && _q_fromHex(src, d4[3]) + && _q_fromHex(src, d4[4]) + && _q_fromHex(src, d4[5]) + && _q_fromHex(src, d4[6]) + && _q_fromHex(src, d4[7]))) { + return QUuid(d1, d2, d3, d4[0], d4[1], d4[2], d4[3], d4[4], d4[5], d4[6], d4[7]); + } } - return true; + return QUuid(); } #ifndef QT_BOOTSTRAPPED @@ -331,7 +352,7 @@ static QUuid createFromName(const QUuid &ns, const QByteArray &baseData, QCrypto /*! 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 + "{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}" where each '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 @@ -340,45 +361,76 @@ static QUuid createFromName(const QUuid &ns, const QByteArray &baseData, QCrypto \sa toString(), QUuid() */ QUuid::QUuid(const QString &text) + : QUuid(fromString(text)) { - if (text.length() < 36) { - *this = QUuid(); - return; - } +} + +/*! + \since 5.10 - const ushort *data = reinterpret_cast<const ushort *>(text.unicode()); + 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 each '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 returned. See + toString() for an explanation of how the five hex fields map to the + public data members in QUuid. - if (*data == '{' && text.length() < 37) { - *this = QUuid(); - return; - } + \sa toString(), QUuid() +*/ +QUuid QUuid::fromString(QStringView text) Q_DECL_NOTHROW +{ + if (text.size() > MaxStringUuidLength) + text = text.left(MaxStringUuidLength); // text.truncate(MaxStringUuidLength); + + char latin1[MaxStringUuidLength + 1]; + char *dst = latin1; + + for (QChar ch : text) + *dst++ = ch.toLatin1(); + + *dst++ = '\0'; // don't read garbage as potentially valid data - if (!_q_uuidFromHex(data, data1, data2, data3, data4)) { - *this = QUuid(); - return; + return _q_uuidFromHex(latin1); +} + +/*! + \since 5.10 + \overload + + 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 each '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 returned. See + toString() for an explanation of how the five hex fields map to the + public data members in QUuid. + + \sa toString(), QUuid() +*/ +QUuid QUuid::fromString(QLatin1String text) Q_DECL_NOTHROW +{ + if (Q_UNLIKELY(text.size() < MaxStringUuidLength - 2 + || (text.front() == QLatin1Char('{') && text.size() < MaxStringUuidLength - 1))) { + // Too short. Don't call _q_uuidFromHex(); QL1Ss need not be NUL-terminated, + // and we don't want to read trailing garbage as potentially valid data. + text = QLatin1String(); } + return _q_uuidFromHex(text.data()); } /*! \internal */ QUuid::QUuid(const char *text) + : QUuid(_q_uuidFromHex(text)) { - if (!text) { - *this = QUuid(); - return; - } - - if (!_q_uuidFromHex(text, data1, data2, data3, data4)) { - *this = QUuid(); - return; - } } /*! Creates a QUuid object from the QByteArray \a text, which must be formatted as five hex fields separated by '-', e.g., - "{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}" where 'x' is a hex + "{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}" where each '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 toByteArray() for an explanation of how the five hex fields map to the @@ -389,23 +441,8 @@ QUuid::QUuid(const char *text) \sa toByteArray(), QUuid() */ QUuid::QUuid(const QByteArray &text) + : QUuid(fromString(QLatin1String(text.data(), text.size()))) { - if (text.length() < 36) { - *this = QUuid(); - return; - } - - const char *data = text.constData(); - - if (*data == '{' && text.length() < 37) { - *this = QUuid(); - return; - } - - if (!_q_uuidFromHex(data, data1, data2, data3, data4)) { - *this = QUuid(); - return; - } } /*! @@ -548,12 +585,11 @@ QUuid QUuid::fromRfc4122(const QByteArray &bytes) */ QString QUuid::toString() const { - QString result(38, Qt::Uninitialized); - ushort *data = (ushort *)result.data(); - - _q_uuidToHex(data, data1, data2, data3, data4); - - return result; + char latin1[MaxStringUuidLength]; + const auto end = _q_uuidToHex(*this, latin1); + Q_ASSERT(end - latin1 == MaxStringUuidLength); + Q_UNUSED(end); + return QString::fromLatin1(latin1, MaxStringUuidLength); } /*! @@ -594,11 +630,10 @@ QString QUuid::toString() const */ QByteArray QUuid::toByteArray() const { - QByteArray result(38, Qt::Uninitialized); - char *data = result.data(); - - _q_uuidToHex(data, data1, data2, data3, data4); - + QByteArray result(MaxStringUuidLength, Qt::Uninitialized); + const auto end = _q_uuidToHex(*this, const_cast<char*>(result.constData())); + Q_ASSERT(end - result.constData() == MaxStringUuidLength); + Q_UNUSED(end); return result; } |