include/QtCore/qlatin1stringview.h

0001 // Copyright (C) 2020 The Qt Company Ltd.
0002 // Copyright (C) 2019 Intel Corporation.
0003 // Copyright (C) 2019 Mail.ru Group.
0004 // Copyright (C) 2020 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Marc Mutz <marc.mutz@kdab.com>
0005 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
0006 // Qt-Security score:critical reason:data-parser
0007
0008 #ifndef QLATIN1STRINGVIEW_H
0009 #define QLATIN1STRINGVIEW_H
0010
0011 #include <QtCore/qchar.h>
0012 #include <QtCore/qcompare.h>
0013 #include <QtCore/qcontainerfwd.h>
0014 #include <QtCore/qnamespace.h>
0015 #include <QtCore/qtversionchecks.h>
0016 #include <QtCore/qstringfwd.h>
0017 #include <QtCore/qstringview.h>
0018
0019 #if 0
0020 // Workaround for generating forward headers
0021 #pragma qt_class(QLatin1String)
0022 #pragma qt_class(QLatin1StringView)
0023 #endif
0024
0025 QT_BEGIN_NAMESPACE
0026
0027 class QString;
0028
0029 #ifdef Q_L1S_VIEW_IS_PRIMARY
0030 class QLatin1StringView
0031 #else
0032 class QLatin1String
0033 #endif
0034 {
0035 public:
0036 #ifdef Q_L1S_VIEW_IS_PRIMARY
0037     constexpr QLatin1StringView() noexcept {}
0038     constexpr QLatin1StringView(std::nullptr_t) noexcept : QLatin1StringView() {}
0039     constexpr explicit QLatin1StringView(const char *s) noexcept
0040         : QLatin1StringView(s, s ? qsizetype(QtPrivate::lengthHelperPointer(s)) : 0) {}
0041     constexpr QLatin1StringView(const char *f, const char *l)
0042         : QLatin1StringView(f, qsizetype(l - f)) {}
0043     constexpr QLatin1StringView(const char *s, qsizetype sz) noexcept : m_data(s), m_size(sz) {}
0044     explicit QLatin1StringView(const QByteArray &s) noexcept
0045         : QLatin1StringView{s.begin(), s.size()} {}
0046     constexpr explicit QLatin1StringView(QByteArrayView s) noexcept
0047         : QLatin1StringView(s.constData(), s.size()) {}
0048 #else
0049     constexpr QLatin1String() noexcept : m_size(0), m_data(nullptr) {}
0050     Q_WEAK_OVERLOAD
0051     constexpr QLatin1String(std::nullptr_t) noexcept : QLatin1String() {}
0052     constexpr explicit QLatin1String(const char *s) noexcept
0053         : m_size(s ? qsizetype(QtPrivate::lengthHelperPointer(s)) : 0), m_data(s) {}
0054     constexpr QLatin1String(const char *f, const char *l)
0055         : QLatin1String(f, qsizetype(l - f)) {}
0056     constexpr QLatin1String(const char *s, qsizetype sz) noexcept : m_size(sz), m_data(s) {}
0057     explicit QLatin1String(const QByteArray &s) noexcept : QLatin1String(s.begin(), s.size()) {}
0058     constexpr explicit QLatin1String(QByteArrayView s) noexcept : m_size(s.size()), m_data(s.data()) {}
0059 #endif // !Q_L1S_VIEW_IS_PRIMARY
0060
0061     inline QString toString() const;
0062     QByteArray toUtf8() const { return QtPrivate::convertToUtf8(*this); }
0063
0064     constexpr const char *latin1() const noexcept { return m_data; }
0065     constexpr qsizetype size() const noexcept { return m_size; }
0066     constexpr const char *data() const noexcept { return m_data; }
0067     [[nodiscard]] constexpr const char *constData() const noexcept { return data(); }
0068     [[nodiscard]] constexpr const char *constBegin() const noexcept { return begin(); }
0069     [[nodiscard]] constexpr const char *constEnd() const noexcept { return end(); }
0070
0071     [[nodiscard]] constexpr QLatin1Char first() const { return front(); }
0072     [[nodiscard]] constexpr QLatin1Char last() const { return back(); }
0073
0074     [[nodiscard]] constexpr qsizetype length() const noexcept { return size(); }
0075
0076     constexpr bool isNull() const noexcept { return !data(); }
0077     constexpr bool isEmpty() const noexcept { return !size(); }
0078
0079     [[nodiscard]] constexpr bool empty() const noexcept { return size() == 0; }
0080
0081     template <typename...Args>
0082     [[nodiscard]] inline QString arg(Args &&...args) const;
0083
0084     [[nodiscard]] constexpr QLatin1Char at(qsizetype i) const
0085     {
0086         Q_ASSERT(i >= 0);
0087         Q_ASSERT(i < size());
0088         return QLatin1Char(m_data[i]);
0089     }
0090     [[nodiscard]] constexpr QLatin1Char operator[](qsizetype i) const { return at(i); }
0091
0092     [[nodiscard]] constexpr QLatin1Char front() const { return at(0); }
0093     [[nodiscard]] constexpr QLatin1Char back() const { return at(size() - 1); }
0094
0095     [[nodiscard]] int compare(QStringView other, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0096     { return QtPrivate::compareStrings(*this, other, cs); }
0097     [[nodiscard]] int compare(QLatin1StringView other, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0098     { return QtPrivate::compareStrings(*this, other, cs); }
0099     [[nodiscard]] inline int compare(QUtf8StringView other, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept;
0100     [[nodiscard]] constexpr int compare(QChar c) const noexcept
0101     { return isEmpty() ? -1 : front() == c ? int(size() > 1) : uchar(m_data[0]) - c.unicode(); }
0102     [[nodiscard]] int compare(QChar c, Qt::CaseSensitivity cs) const noexcept
0103     { return QtPrivate::compareStrings(*this, QStringView(&c, 1), cs); }
0104
0105     [[nodiscard]] bool startsWith(QStringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0106     { return QtPrivate::startsWith(*this, s, cs); }
0107     [[nodiscard]] bool startsWith(QLatin1StringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0108     { return QtPrivate::startsWith(*this, s, cs); }
0109     [[nodiscard]] constexpr bool startsWith(QChar c) const noexcept
0110     { return !isEmpty() && front() == c; }
0111     [[nodiscard]] bool startsWith(QChar c, Qt::CaseSensitivity cs) const noexcept
0112     { return QtPrivate::startsWith(*this, QStringView(&c, 1), cs); }
0113
0114     [[nodiscard]] bool endsWith(QStringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0115     { return QtPrivate::endsWith(*this, s, cs); }
0116     [[nodiscard]] bool endsWith(QLatin1StringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0117     { return QtPrivate::endsWith(*this, s, cs); }
0118     [[nodiscard]] constexpr bool endsWith(QChar c) const noexcept
0119     { return !isEmpty() && back() == c; }
0120     [[nodiscard]] bool endsWith(QChar c, Qt::CaseSensitivity cs) const noexcept
0121     { return QtPrivate::endsWith(*this, QStringView(&c, 1), cs); }
0122
0123     [[nodiscard]] qsizetype indexOf(QStringView s, qsizetype from = 0, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0124     { return QtPrivate::findString(*this, from, s, cs); }
0125     [[nodiscard]] qsizetype indexOf(QLatin1StringView s, qsizetype from = 0, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0126     { return QtPrivate::findString(*this, from, s, cs); }
0127     [[nodiscard]] qsizetype indexOf(QChar c, qsizetype from = 0, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0128     { return QtPrivate::findString(*this, from, QStringView(&c, 1), cs); }
0129
0130     [[nodiscard]] bool contains(QStringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0131     { return indexOf(s, 0, cs) != -1; }
0132     [[nodiscard]] bool contains(QLatin1StringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0133     { return indexOf(s, 0, cs) != -1; }
0134     [[nodiscard]] bool contains(QChar c, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0135     { return indexOf(QStringView(&c, 1), 0, cs) != -1; }
0136
0137     [[nodiscard]] qsizetype lastIndexOf(QStringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0138     { return lastIndexOf(s, size(), cs); }
0139     [[nodiscard]] qsizetype lastIndexOf(QStringView s, qsizetype from, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0140     { return QtPrivate::lastIndexOf(*this, from, s, cs); }
0141     [[nodiscard]] qsizetype lastIndexOf(QLatin1StringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0142     { return lastIndexOf(s, size(), cs); }
0143     [[nodiscard]] qsizetype lastIndexOf(QLatin1StringView s, qsizetype from, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0144     { return QtPrivate::lastIndexOf(*this, from, s, cs); }
0145     [[nodiscard]] qsizetype lastIndexOf(QChar c, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0146     { return lastIndexOf(c, -1, cs); }
0147     [[nodiscard]] qsizetype lastIndexOf(QChar c, qsizetype from, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0148     { return QtPrivate::lastIndexOf(*this, from, QStringView(&c, 1), cs); }
0149
0150     [[nodiscard]] qsizetype count(QStringView str, Qt::CaseSensitivity cs = Qt::CaseSensitive) const
0151     { return QtPrivate::count(*this, str, cs); }
0152     [[nodiscard]] qsizetype count(QLatin1StringView str, Qt::CaseSensitivity cs = Qt::CaseSensitive) const
0153     { return QtPrivate::count(*this, str, cs); }
0154     [[nodiscard]] qsizetype count(QChar ch, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
0155     { return QtPrivate::count(*this, ch, cs); }
0156
0157     [[nodiscard]] short toShort(bool *ok = nullptr, int base = 10) const
0158     { return QtPrivate::toIntegral<short>(QByteArrayView(*this), ok, base); }
0159     [[nodiscard]] ushort toUShort(bool *ok = nullptr, int base = 10) const
0160     { return QtPrivate::toIntegral<ushort>(QByteArrayView(*this), ok, base); }
0161     [[nodiscard]] int toInt(bool *ok = nullptr, int base = 10) const
0162     { return QtPrivate::toIntegral<int>(QByteArrayView(*this), ok, base); }
0163     [[nodiscard]] uint toUInt(bool *ok = nullptr, int base = 10) const
0164     { return QtPrivate::toIntegral<uint>(QByteArrayView(*this), ok, base); }
0165     [[nodiscard]] long toLong(bool *ok = nullptr, int base = 10) const
0166     { return QtPrivate::toIntegral<long>(QByteArrayView(*this), ok, base); }
0167     [[nodiscard]] ulong toULong(bool *ok = nullptr, int base = 10) const
0168     { return QtPrivate::toIntegral<ulong>(QByteArrayView(*this), ok, base); }
0169     [[nodiscard]] qlonglong toLongLong(bool *ok = nullptr, int base = 10) const
0170     { return QtPrivate::toIntegral<qlonglong>(QByteArrayView(*this), ok, base); }
0171     [[nodiscard]] qulonglong toULongLong(bool *ok = nullptr, int base = 10) const
0172     { return QtPrivate::toIntegral<qulonglong>(QByteArrayView(*this), ok, base); }
0173     [[nodiscard]] float toFloat(bool *ok = nullptr) const
0174     {
0175         const auto r = QtPrivate::toFloat(*this);
0176         if (ok)
0177             *ok = bool(r);
0178         return r.value_or(0.0f);
0179     }
0180     [[nodiscard]] double toDouble(bool *ok = nullptr) const
0181     {
0182         const auto r = QtPrivate::toDouble(*this);
0183         if (ok)
0184             *ok = bool(r);
0185         return r.value_or(0.0);
0186     }
0187
0188     using value_type = const char;
0189     using pointer = value_type*;
0190     using const_pointer = pointer;
0191     using reference = value_type&;
0192     using const_reference = reference;
0193     using iterator = value_type*;
0194     using const_iterator = iterator;
0195     using difference_type = qsizetype; // violates Container concept requirements
0196     using size_type = qsizetype;       // violates Container concept requirements
0197
0198     constexpr const_iterator begin() const noexcept { return data(); }
0199     constexpr const_iterator cbegin() const noexcept { return data(); }
0200     constexpr const_iterator end() const noexcept { return data() + size(); }
0201     constexpr const_iterator cend() const noexcept { return data() + size(); }
0202
0203     using reverse_iterator = std::reverse_iterator<iterator>;
0204     using const_reverse_iterator = reverse_iterator;
0205
0206     const_reverse_iterator rbegin() const noexcept { return const_reverse_iterator(end()); }
0207     const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator(end()); }
0208     const_reverse_iterator rend() const noexcept { return const_reverse_iterator(begin()); }
0209     const_reverse_iterator crend() const noexcept { return const_reverse_iterator(begin()); }
0210
0211     [[nodiscard]] constexpr qsizetype max_size() const noexcept { return maxSize(); }
0212
0213     [[nodiscard]] static constexpr qsizetype maxSize() noexcept
0214     {
0215         // -1 to deal with the pointer one-past-the-end;
0216         return QtPrivate::MaxAllocSize - 1;
0217     }
0218
0219     [[nodiscard]] constexpr QLatin1StringView mid(qsizetype pos, qsizetype n = -1) const
0220     {
0221         using namespace QtPrivate;
0222         auto result = QContainerImplHelper::mid(size(), &pos, &n);
0223         return result == QContainerImplHelper::Null ? QLatin1StringView()
0224                                                     : QLatin1StringView(m_data + pos, n);
0225     }
0226     [[nodiscard]] constexpr QLatin1StringView left(qsizetype n) const
0227     {
0228         if (size_t(n) >= size_t(size()))
0229             n = size();
0230         return {m_data, n};
0231     }
0232     [[nodiscard]] constexpr QLatin1StringView right(qsizetype n) const
0233     {
0234         if (size_t(n) >= size_t(size()))
0235             n = size();
0236         return {m_data + m_size - n, n};
0237     }
0238
0239     [[nodiscard]] constexpr QLatin1StringView sliced(qsizetype pos) const
0240     { verify(pos, 0); return {m_data + pos, m_size - pos}; }
0241     [[nodiscard]] constexpr QLatin1StringView sliced(qsizetype pos, qsizetype n) const
0242     { verify(pos, n); return {m_data + pos, n}; }
0243     [[nodiscard]] constexpr QLatin1StringView first(qsizetype n) const
0244     { verify(0, n); return sliced(0, n); }
0245     [[nodiscard]] constexpr QLatin1StringView last(qsizetype n) const
0246     { verify(0, n); return sliced(size() - n, n); }
0247     [[nodiscard]] constexpr QLatin1StringView chopped(qsizetype n) const
0248     { verify(0, n); return sliced(0, size() - n); }
0249
0250     constexpr QLatin1StringView &slice(qsizetype pos)
0251     { *this = sliced(pos); return *this; }
0252     constexpr QLatin1StringView &slice(qsizetype pos, qsizetype n)
0253     { *this = sliced(pos, n); return *this; }
0254
0255     constexpr void chop(qsizetype n)
0256     { verify(0, n); m_size -= n; }
0257     constexpr void truncate(qsizetype n)
0258     { verify(0, n); m_size = n; }
0259
0260     [[nodiscard]] QLatin1StringView trimmed() const noexcept { return QtPrivate::trimmed(*this); }
0261
0262     template <typename Needle, typename...Flags>
0263     [[nodiscard]] constexpr auto tokenize(Needle &&needle, Flags...flags) const
0264         noexcept(noexcept(qTokenize(std::declval<const QLatin1StringView &>(),
0265                                     std::forward<Needle>(needle), flags...)))
0266             -> decltype(qTokenize(*this, std::forward<Needle>(needle), flags...))
0267     { return qTokenize(*this, std::forward<Needle>(needle), flags...); }
0268
0269     friend bool comparesEqual(const QLatin1StringView &s1, const QLatin1StringView &s2) noexcept
0270     { return s1.size() == s2.size() && QtPrivate::equalStrings(s1, s2); }
0271     friend Qt::strong_ordering
0272     compareThreeWay(const QLatin1StringView &s1, const QLatin1StringView &s2) noexcept
0273     {
0274         const int res = QtPrivate::compareStrings(s1, s2);
0275         return Qt::compareThreeWay(res, 0);
0276     }
0277     Q_DECLARE_STRONGLY_ORDERED(QLatin1StringView)
0278
0279     // QChar <> QLatin1StringView
0280     friend bool comparesEqual(const QLatin1StringView &lhs, QChar rhs) noexcept
0281     { return lhs.size() == 1 && rhs == lhs.front(); }
0282     friend Qt::strong_ordering
0283     compareThreeWay(const QLatin1StringView &lhs, QChar rhs) noexcept
0284     {
0285         // negate, as the helper function expects QChar as lhs
0286         const int res = -compare_helper(&rhs, 1, lhs);
0287         return Qt::compareThreeWay(res, 0);
0288     }
0289     Q_DECLARE_STRONGLY_ORDERED(QLatin1StringView, QChar)
0290
0291     // QStringView <> QLatin1StringView
0292     friend bool comparesEqual(const QLatin1StringView &lhs, const QStringView &rhs) noexcept
0293     { return lhs.size() == rhs.size() && QtPrivate::equalStrings(lhs, rhs); }
0294     friend Qt::strong_ordering
0295     compareThreeWay(const QLatin1StringView &lhs, const QStringView &rhs) noexcept
0296     {
0297         const int res = QtPrivate::compareStrings(lhs, rhs);
0298         return Qt::compareThreeWay(res, 0);
0299     }
0300     Q_DECLARE_STRONGLY_ORDERED(QLatin1StringView, QStringView)
0301
0302     // Reversed helper methods for QStringView <> QLatin1StringView comparison.
0303     // If we do not provide them explicitly, QStringView <> QByteArrayView
0304     // overloads will be selected, which will provide wrong results, because
0305     // they will convert from utf-8
0306     friend bool comparesEqual(const QStringView &lhs, const QLatin1StringView &rhs) noexcept
0307     { return comparesEqual(rhs, lhs); }
0308     friend Qt::strong_ordering
0309     compareThreeWay(const QStringView &lhs, const QLatin1StringView &rhs) noexcept
0310     { return QtOrderingPrivate::reversed(compareThreeWay(rhs, lhs)); }
0311
0312 private:
0313     friend bool comparesEqual(const QLatin1StringView &lhs, const QByteArrayView &rhs) noexcept
0314     { return equal_helper(lhs, rhs.data(), rhs.size()); }
0315     friend Qt::strong_ordering
0316     compareThreeWay(const QLatin1StringView &lhs, const QByteArrayView &rhs) noexcept
0317     {
0318         const int res = compare_helper(lhs, rhs.data(), rhs.size());
0319         return Qt::compareThreeWay(res, 0);
0320     }
0321
0322     // Reversed helper methods for QByteArrayView <> QLatin1StringView comparison.
0323     // If we do not provide them explicitly, QByteArrayView <> QByteArrayView
0324     // overloads will be selected, which will provide wrong results
0325     friend bool comparesEqual(const QByteArrayView &lhs, const QLatin1StringView &rhs) noexcept
0326     { return comparesEqual(rhs, lhs); }
0327     friend Qt::strong_ordering
0328     compareThreeWay(const QByteArrayView &lhs, const QLatin1StringView &rhs) noexcept
0329     { return QtOrderingPrivate::reversed(compareThreeWay(rhs, lhs)); }
0330
0331 public:
0332 #if !defined(QT_NO_CAST_FROM_ASCII) && !defined(QT_RESTRICTED_CAST_FROM_ASCII)
0333     Q_DECLARE_STRONGLY_ORDERED(QLatin1StringView, QByteArrayView, QT_ASCII_CAST_WARN)
0334     Q_DECLARE_STRONGLY_ORDERED(QLatin1StringView, QByteArray, QT_ASCII_CAST_WARN)
0335     Q_DECLARE_STRONGLY_ORDERED(QLatin1StringView, const char *, QT_ASCII_CAST_WARN)
0336 #endif // !defined(QT_NO_CAST_FROM_ASCII) && !defined(QT_RESTRICTED_CAST_FROM_ASCII)
0337
0338 private:
0339     Q_ALWAYS_INLINE constexpr void verify([[maybe_unused]] qsizetype pos,
0340                                           [[maybe_unused]] qsizetype n = 1) const
0341     {
0342         Q_ASSERT(pos >= 0);
0343         Q_ASSERT(pos <= size());
0344         Q_ASSERT(n >= 0);
0345         Q_ASSERT(n <= size() - pos);
0346     }
0347     static int compare_helper(const QLatin1StringView &s1, const char *s2) noexcept
0348     { return compare_helper(s1, s2, qstrlen(s2)); }
0349     Q_CORE_EXPORT static bool equal_helper(QLatin1StringView s1, const char *s2, qsizetype len) noexcept;
0350     Q_CORE_EXPORT static int compare_helper(const QLatin1StringView &s1, const char *s2, qsizetype len) noexcept;
0351     Q_CORE_EXPORT static int compare_helper(const QChar *data1, qsizetype length1,
0352                                             QLatin1StringView s2,
0353                                             Qt::CaseSensitivity cs = Qt::CaseSensitive) noexcept;
0354 #if QT_VERSION >= QT_VERSION_CHECK(7, 0, 0) || defined(QT_BOOTSTRAPPED)
0355     const char *m_data = nullptr;
0356     qsizetype m_size = 0;
0357 #else
0358     qsizetype m_size;
0359     const char *m_data;
0360 #endif
0361 };
0362 #ifdef Q_L1S_VIEW_IS_PRIMARY
0363 Q_DECLARE_TYPEINFO(QLatin1StringView, Q_RELOCATABLE_TYPE);
0364 #else
0365 Q_DECLARE_TYPEINFO(QLatin1String, Q_RELOCATABLE_TYPE);
0366 #endif
0367
0368 namespace Qt {
0369 inline namespace Literals {
0370 inline namespace StringLiterals {
0371
0372 constexpr inline QLatin1StringView operator""_L1(const char *str, size_t size) noexcept
0373 {
0374     return {str, qsizetype(size)};
0375 }
0376
0377 } // StringLiterals
0378 } // Literals
0379 } // Qt
0380
0381 QT_END_NAMESPACE
0382
0383 #ifdef Q_L1S_VIEW_IS_PRIMARY
0384 #    undef Q_L1S_VIEW_IS_PRIMARY
0385 #endif
0386
0387 #endif // QLATIN1STRINGVIEW_H