diff options
Diffstat (limited to 'src/corelib/tools/qoffsetstringarray_p.h')
| -rw-r--r-- | src/corelib/tools/qoffsetstringarray_p.h | 246 |
1 files changed, 104 insertions, 142 deletions
diff --git a/src/corelib/tools/qoffsetstringarray_p.h b/src/corelib/tools/qoffsetstringarray_p.h index 4dd9e9603b..9103606a13 100644 --- a/src/corelib/tools/qoffsetstringarray_p.h +++ b/src/corelib/tools/qoffsetstringarray_p.h @@ -1,41 +1,6 @@ -/**************************************************************************** -** -** Copyright (C) 2018 The Qt Company Ltd. -** Contact: https://www.qt.io/licensing/ -** -** This file is part of the QtCore module of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:LGPL$ -** Commercial License Usage -** Licensees holding valid commercial Qt licenses may use this file in -** accordance with the commercial license agreement provided with the -** Software or, alternatively, in accordance with the terms contained in -** a written agreement between you and The Qt Company. For licensing terms -** and conditions see https://www.qt.io/terms-conditions. For further -** information use the contact form at https://www.qt.io/contact-us. -** -** GNU Lesser General Public License Usage -** Alternatively, this file may be used under the terms of the GNU Lesser -** General Public License version 3 as published by the Free Software -** Foundation and appearing in the file LICENSE.LGPL3 included in the -** packaging of this file. Please review the following information to -** ensure the GNU Lesser General Public License version 3 requirements -** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. -** -** GNU General Public License Usage -** Alternatively, this file may be used under the terms of the GNU -** General Public License version 2.0 or (at your option) the GNU General -** Public license version 3 or any later version approved by the KDE Free -** Qt Foundation. The licenses are as published by the Free Software -** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 -** included in the packaging of this file. Please review the following -** information to ensure the GNU General Public License requirements will -** be met: https://www.gnu.org/licenses/gpl-2.0.html and -** https://www.gnu.org/licenses/gpl-3.0.html. -** -** $QT_END_LICENSE$ -** -****************************************************************************/ +// Copyright (C) 2020 The Qt Company Ltd. +// Copyright (C) 2021 Intel Corporation. +// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only #ifndef QOFFSETSTRINGARRAY_P_H #define QOFFSETSTRINGARRAY_P_H @@ -53,146 +18,143 @@ #include "private/qglobal_p.h" -#include <tuple> +#include <QByteArrayView> + +#include <QtCore/q20algorithm.h> #include <array> +#include <limits> +#include <string_view> +#include <tuple> -QT_BEGIN_NAMESPACE +class tst_QOffsetStringArray; -namespace QtPrivate { -template<int N, int O, int I, int ... Idx> -struct OffsetSequenceHelper : OffsetSequenceHelper<N - 1, O + I, Idx..., O> { }; +QT_BEGIN_NAMESPACE -template<int Last, int I, int S, int ... Idx> -struct OffsetSequenceHelper<1, Last, I, S, Idx...> : IndexesList<Last + I, Idx..., Last> -{ - static const constexpr auto Length = Last + I; - using Type = typename std::conditional< - Last <= std::numeric_limits<quint8>::max(), - quint8, - typename std::conditional< - Last <= std::numeric_limits<quint16>::max(), - quint16, - int>::type - >::type; -}; +QT_WARNING_PUSH +#if defined(Q_CC_GNU_ONLY) && Q_CC_GNU >= 1100 +// we usually don't overread, but GCC has a false positive +QT_WARNING_DISABLE_GCC("-Wstringop-overread") +#endif -template<int ... Idx> -struct OffsetSequence : OffsetSequenceHelper<sizeof ... (Idx), 0, Idx..., 0> { }; -template<int N> -struct StaticString +template <typename StaticString, typename OffsetList> +class QOffsetStringArray { - const char data[N]; -}; +public: + constexpr QOffsetStringArray(const StaticString &string, const OffsetList &offsets) + : m_string(string), m_offsets(offsets) + {} + constexpr const char *operator[](const int index) const noexcept + { + return m_string.data() + m_offsets[qBound(int(0), index, count())]; + } -template<> -struct StaticString<0> -{ - static constexpr int size() noexcept + constexpr const char *at(const int index) const noexcept { - return 0; + return m_string.data() + m_offsets[index]; } -}; -template<typename, typename> -struct StaticStringBuilder; + constexpr QByteArrayView viewAt(qsizetype index) const noexcept + { + return { m_string.data() + m_offsets[index], + qsizetype(m_offsets[index + 1]) - qsizetype(m_offsets[index]) - 1 }; + } -template<int ... I1, int ... I2> -struct StaticStringBuilder<IndexesList<I1...>, IndexesList<I2...>> -{ + constexpr int count() const { return int(m_offsets.size()) - 1; } -QT_WARNING_PUSH -QT_WARNING_DISABLE_MSVC(4100) // The formal parameter is not referenced in the body of the function. - // The unreferenced parameter is ignored. - // It happens when 'rs' is StaticString<0> - template<int N1, int N2> - static constexpr StaticString<N1 + N2> concatenate( - const char (&ls)[N1], const StaticString<N2> &rs) noexcept + bool contains(QByteArrayView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept { - return StaticString<N1 + N2>{{ls[I1]..., rs.data[I2]...}}; + for (qsizetype i = 0; i < count(); ++i) { + if (viewAt(i).compare(needle, cs) == 0) + return true; + } + return false; } -QT_WARNING_POP + +private: + StaticString m_string; + OffsetList m_offsets; + friend tst_QOffsetStringArray; }; -template<int Sum> -constexpr StaticString<0> staticString() noexcept +namespace QtPrivate { +template <size_t Highest> constexpr auto minifyValue() { - return StaticString<0>{}; + constexpr size_t max8 = (std::numeric_limits<quint8>::max)(); + constexpr size_t max16 = (std::numeric_limits<quint16>::max)(); + if constexpr (Highest <= max8) { + return quint8(Highest); + } else if constexpr (Highest <= max16) { + return quint16(Highest); + } else { + // int is probably enough for everyone + return int(Highest); + } } -QT_WARNING_PUSH -QT_WARNING_DISABLE_MSVC(4503) -template<int Sum, int I, int ... Ix> -constexpr StaticString<Sum> staticString(const char (&s)[I], const char (&...sx)[Ix]) noexcept +template <size_t StringLength, typename Extractor, typename... T> +constexpr auto makeStaticString(Extractor extract, const T &... entries) { - return StaticStringBuilder< - makeIndexSequence<I>, - makeIndexSequence<Sum - I>>::concatenate(s, staticString<Sum - I>(sx...)); + std::array<char, StringLength> result = {}; + qptrdiff offset = 0; + + const char *strings[] = { extract(entries).operator const char *()... }; + size_t lengths[] = { sizeof(extract(T{}))... }; + for (size_t i = 0; i < std::size(strings); ++i) { + q20::copy_n(strings[i], lengths[i], result.begin() + offset); + offset += lengths[i]; + } + return result; } -QT_WARNING_POP -} // namespace QtPrivate -template<typename T, int SizeString, int SizeOffsets> -class QOffsetStringArray +template <size_t N> struct StaticString { -public: - using Type = T; - - template<int ... Ox> - constexpr QOffsetStringArray(const QtPrivate::StaticString<SizeString> &str, - QtPrivate::IndexesList<SizeString, Ox...>) noexcept - : m_string(str), - m_offsets{Ox...} - { } - - constexpr inline const char *operator[](const int index) const noexcept - { - return m_string.data + m_offsets[qBound(int(0), index, SizeOffsets - 1)]; - } + char value[N] = {}; + constexpr StaticString() = default; + constexpr StaticString(const char (&s)[N]) { q20::copy_n(s, N, value); } + constexpr operator const char *() const { return value; } +}; - constexpr inline const char *at(const int index) const noexcept - { - return m_string.data + m_offsets[index]; - } +template <size_t KL, size_t VL> struct StaticMapEntry +{ + StaticString<KL> key = {}; + StaticString<VL> value = {}; + constexpr StaticMapEntry() = default; + constexpr StaticMapEntry(const char (&k)[KL], const char (&v)[VL]) + : key(k), value(v) + {} +}; - constexpr inline const char *str() const { return m_string.data; } - constexpr inline const T *offsets() const { return m_offsets; } - constexpr inline int count() const { return SizeOffsets; }; +template <typename StringExtractor, typename... T> +constexpr auto makeOffsetStringArray(StringExtractor extractString, const T &... entries) +{ + constexpr size_t Count = sizeof...(T); + constexpr size_t StringLength = (sizeof(extractString(T{})) + ...); + using MinifiedOffsetType = decltype(QtPrivate::minifyValue<StringLength>()); - static constexpr const auto sizeString = SizeString; - static constexpr const auto sizeOffsets = SizeOffsets; + size_t offset = 0; + std::array fullOffsetList = { offset += sizeof(extractString(T{}))... }; -private: - QtPrivate::StaticString<SizeString> m_string; - const T m_offsets[SizeOffsets]; -}; + // prepend zero + std::array<MinifiedOffsetType, Count + 1> minifiedOffsetList = {}; + q20::transform(fullOffsetList.begin(), fullOffsetList.end(), + minifiedOffsetList.begin() + 1, + [] (auto e) { return MinifiedOffsetType(e); }); -template<typename T, int N, int ... Ox> -constexpr QOffsetStringArray<T, N, sizeof ... (Ox)> qOffsetStringArray( - const QtPrivate::StaticString<N> &string, - QtPrivate::IndexesList<N, Ox...> offsets) noexcept -{ - return QOffsetStringArray<T, N, sizeof ... (Ox)>( - string, - offsets); + std::array staticString = QtPrivate::makeStaticString<StringLength>(extractString, entries...); + return QOffsetStringArray(staticString, minifiedOffsetList); } +} // namespace QtPrivate template<int ... Nx> -struct QOffsetStringArrayRet -{ - using Offsets = QtPrivate::OffsetSequence<Nx...>; - using Type = QOffsetStringArray<typename Offsets::Type, Offsets::Length, sizeof ... (Nx)>; -}; - -template<int ... Nx> -constexpr auto qOffsetStringArray(const char (&...strings)[Nx]) noexcept -> typename QOffsetStringArrayRet<Nx...>::Type +constexpr auto qOffsetStringArray(const char (&...strings)[Nx]) noexcept { - using Offsets = QtPrivate::OffsetSequence<Nx...>; - return qOffsetStringArray<typename Offsets::Type>( - QtPrivate::staticString<Offsets::Length>(strings...), Offsets{}); + auto extractString = [](const auto &s) -> decltype(auto) { return s; }; + return QtPrivate::makeOffsetStringArray(extractString, QtPrivate::StaticString(strings)...); } +QT_WARNING_POP QT_END_NAMESPACE #endif // QOFFSETSTRINGARRAY_P_H |