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// Copyright (C) 2020 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Marc Mutz <marc.mutz@kdab.com>
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
// Qt-Security score:critical reason:data-parser
#ifndef QUTF8STRINGVIEW_H
#define QUTF8STRINGVIEW_H
#if 0
#pragma qt_class(QUtf8StringView)
#endif
#include <QtCore/qstringalgorithms.h>
#include <QtCore/qstringfwd.h>
#include <QtCore/qarraydata.h> // for QContainerImplHelper
#include <QtCore/qbytearrayview.h>
#include <QtCore/qcompare.h>
#include <QtCore/qcontainerfwd.h>
#include <string>
#include <string_view>
#include <QtCore/q20type_traits.h>
QT_BEGIN_NAMESPACE
namespace QtPrivate {
template <typename Char>
using IsCompatibleChar8TypeHelper = std::disjunction<
#ifdef __cpp_char8_t
std::is_same<Char, char8_t>,
#endif
std::is_same<Char, char>,
std::is_same<Char, uchar>,
std::is_same<Char, signed char>
>;
template <typename Char>
using IsCompatibleChar8Type
= IsCompatibleChar8TypeHelper<q20::remove_cvref_t<Char>>;
template <typename Pointer>
struct IsCompatiblePointer8Helper : std::false_type {};
template <typename Char>
struct IsCompatiblePointer8Helper<Char*>
: IsCompatibleChar8Type<Char> {};
template <typename Pointer>
using IsCompatiblePointer8
= IsCompatiblePointer8Helper<q20::remove_cvref_t<Pointer>>;
template <typename T, typename Enable = void>
struct IsContainerCompatibleWithQUtf8StringView : std::false_type {};
template <typename T>
struct IsContainerCompatibleWithQUtf8StringView<T, std::enable_if_t<std::conjunction_v<
// lacking concepts and ranges, we accept any T whose std::data yields a suitable pointer ...
IsCompatiblePointer8<decltype(std::data(std::declval<const T &>()))>,
// ... and that has a suitable size ...
std::is_convertible<
decltype(std::size(std::declval<const T &>())),
qsizetype
>,
// ... and it's a range as it defines an iterator-like API
IsCompatibleChar8Type<typename std::iterator_traits<
decltype(std::begin(std::declval<const T &>()))>::value_type
>,
std::is_convertible<
decltype( std::begin(std::declval<const T &>()) != std::end(std::declval<const T &>()) ),
bool
>,
// This needs to be treated specially due to the empty vs null distinction
std::negation<std::is_same<std::decay_t<T>, QByteArray>>,
// This has a compatible value_type, but explicitly a different encoding
std::negation<std::is_same<std::decay_t<T>, QLatin1StringView>>,
// Don't make an accidental copy constructor
std::negation<std::disjunction<
std::is_same<std::decay_t<T>, QBasicUtf8StringView<true>>,
std::is_same<std::decay_t<T>, QBasicUtf8StringView<false>>
>>
>>> : std::true_type {};
struct hide_char8_t {
#ifdef __cpp_char8_t
using type = char8_t;
#endif
};
struct wrap_char { using type = char; };
} // namespace QtPrivate
#ifdef Q_QDOC
#define QBasicUtf8StringView QUtf8StringView
#else
template <bool UseChar8T>
#endif
class QBasicUtf8StringView
{
public:
#ifndef Q_QDOC
using storage_type = typename std::conditional<UseChar8T,
QtPrivate::hide_char8_t,
QtPrivate::wrap_char
>::type::type;
#else
using storage_type = typename QtPrivate::hide_char8_t;
#endif
typedef const storage_type value_type;
typedef qptrdiff difference_type;
typedef qsizetype size_type;
typedef value_type &reference;
typedef value_type &const_reference;
typedef value_type *pointer;
typedef value_type *const_pointer;
typedef pointer iterator;
typedef const_pointer const_iterator;
typedef std::reverse_iterator<iterator> reverse_iterator;
typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
private:
template <typename Char>
using if_compatible_char = std::enable_if_t<QtPrivate::IsCompatibleChar8Type<Char>::value, bool>;
template <typename Pointer>
using if_compatible_pointer = std::enable_if_t<QtPrivate::IsCompatiblePointer8<Pointer>::value, bool>;
template <typename T>
using if_compatible_qstring_like = std::enable_if_t<std::is_same_v<T, QByteArray>, bool>;
template <typename T>
using if_compatible_container = std::enable_if_t<QtPrivate::IsContainerCompatibleWithQUtf8StringView<T>::value, bool>;
template <typename Container>
static constexpr qsizetype lengthHelperContainer(const Container &c) noexcept
{
return qsizetype(std::size(c));
}
// Note: Do not replace with std::size(const Char (&)[N]), because the result
// will be of by one.
template <typename Char, size_t N>
static constexpr qsizetype lengthHelperContainer(const Char (&str)[N]) noexcept
{
return QtPrivate::lengthHelperContainer(str);
}
template <typename Char>
static const storage_type *castHelper(const Char *str) noexcept
{ return reinterpret_cast<const storage_type*>(str); }
static constexpr const storage_type *castHelper(const storage_type *str) noexcept
{ return str; }
public:
constexpr QBasicUtf8StringView() noexcept
: m_data(nullptr), m_size(0) {}
constexpr QBasicUtf8StringView(std::nullptr_t) noexcept
: QBasicUtf8StringView() {}
template <typename Char, if_compatible_char<Char> = true>
constexpr QBasicUtf8StringView(const Char *str, qsizetype len)
: m_data(castHelper(str)),
m_size((Q_ASSERT(len >= 0), Q_ASSERT(str || !len), len)) {}
template <typename Char, if_compatible_char<Char> = true>
constexpr QBasicUtf8StringView(const Char *f, const Char *l)
: QBasicUtf8StringView(f, l - f) {}
#ifdef Q_QDOC
template <typename Char, size_t N>
constexpr QBasicUtf8StringView(const Char (&array)[N]) noexcept;
template <typename Char>
constexpr QBasicUtf8StringView(const Char *str) noexcept;
#else
template <typename Pointer, if_compatible_pointer<Pointer> = true>
constexpr QBasicUtf8StringView(const Pointer &str) noexcept
: QBasicUtf8StringView(str, QtPrivate::lengthHelperPointer(str)) {}
template <typename Char, if_compatible_char<Char> = true>
constexpr QBasicUtf8StringView(const Char (&str)[]) noexcept
: QBasicUtf8StringView(&*str) {} // decay to pointer
#endif
#ifdef Q_QDOC
QBasicUtf8StringView(const QByteArray &str) noexcept;
constexpr QBasicUtf8StringView(const storage_type *d, qsizetype n) noexcept {};
#else
template <typename String, if_compatible_qstring_like<String> = true>
QBasicUtf8StringView(const String &str) noexcept
: QBasicUtf8StringView{str.begin(), str.size()} {}
#endif
template <typename Container, if_compatible_container<Container> = true>
constexpr QBasicUtf8StringView(const Container &c) noexcept
: QBasicUtf8StringView(std::data(c), lengthHelperContainer(c)) {}
#if defined(__cpp_char8_t) && !defined(Q_QDOC)
constexpr QBasicUtf8StringView(QBasicUtf8StringView<!UseChar8T> other)
: QBasicUtf8StringView(other.data(), other.size()) {}
#endif
template <typename Char, size_t Size, if_compatible_char<Char> = true>
[[nodiscard]] constexpr static QBasicUtf8StringView fromArray(const Char (&string)[Size]) noexcept
{ return QBasicUtf8StringView(string, Size); }
[[nodiscard]] inline QString toString() const; // defined in qstring.h
[[nodiscard]] constexpr qsizetype size() const noexcept { return m_size; }
[[nodiscard]] constexpr const_pointer data() const noexcept { return m_data; }
#ifdef __cpp_char8_t
[[nodiscard]] const char8_t *utf8() const noexcept { return reinterpret_cast<const char8_t*>(m_data); }
#endif
[[nodiscard]] constexpr storage_type operator[](qsizetype n) const
{ verify(n, 1); return m_data[n]; }
//
// QString API
//
[[nodiscard]] constexpr storage_type at(qsizetype n) const { return (*this)[n]; }
template <typename...Args>
[[nodiscard]] inline QString arg(Args &&...args) const;
[[nodiscard]]
constexpr QBasicUtf8StringView mid(qsizetype pos, qsizetype n = -1) const
{
using namespace QtPrivate;
auto result = QContainerImplHelper::mid(size(), &pos, &n);
return result == QContainerImplHelper::Null ? QBasicUtf8StringView() : QBasicUtf8StringView(m_data + pos, n);
}
[[nodiscard]]
constexpr QBasicUtf8StringView left(qsizetype n) const
{
if (size_t(n) >= size_t(size()))
n = size();
return QBasicUtf8StringView(m_data, n);
}
[[nodiscard]]
constexpr QBasicUtf8StringView right(qsizetype n) const
{
if (size_t(n) >= size_t(size()))
n = size();
return QBasicUtf8StringView(m_data + m_size - n, n);
}
[[nodiscard]] constexpr QBasicUtf8StringView sliced(qsizetype pos) const
{ verify(pos, 0); return QBasicUtf8StringView{m_data + pos, m_size - pos}; }
[[nodiscard]] constexpr QBasicUtf8StringView sliced(qsizetype pos, qsizetype n) const
{ verify(pos, n); return QBasicUtf8StringView(m_data + pos, n); }
[[nodiscard]] constexpr QBasicUtf8StringView first(qsizetype n) const
{ verify(0, n); return sliced(0, n); }
[[nodiscard]] constexpr QBasicUtf8StringView last(qsizetype n) const
{ verify(0, n); return sliced(m_size - n, n); }
[[nodiscard]] constexpr QBasicUtf8StringView chopped(qsizetype n) const
{ verify(0, n); return sliced(0, m_size - n); }
constexpr QBasicUtf8StringView &slice(qsizetype pos)
{ *this = sliced(pos); return *this; }
constexpr QBasicUtf8StringView &slice(qsizetype pos, qsizetype n)
{ *this = sliced(pos, n); return *this; }
constexpr void truncate(qsizetype n)
{ verify(0, n); m_size = n; }
constexpr void chop(qsizetype n)
{ verify(0, n); m_size -= n; }
[[nodiscard]] inline bool isValidUtf8() const noexcept
{
return QByteArrayView(reinterpret_cast<const char *>(data()), size()).isValidUtf8();
}
//
// STL compatibility API:
//
[[nodiscard]] const_iterator begin() const noexcept { return data(); }
[[nodiscard]] const_iterator end() const noexcept { return data() + size(); }
[[nodiscard]] const_iterator cbegin() const noexcept { return begin(); }
[[nodiscard]] const_iterator cend() const noexcept { return end(); }
[[nodiscard]] const_reverse_iterator rbegin() const noexcept { return const_reverse_iterator(end()); }
[[nodiscard]] const_reverse_iterator rend() const noexcept { return const_reverse_iterator(begin()); }
[[nodiscard]] const_reverse_iterator crbegin() const noexcept { return rbegin(); }
[[nodiscard]] const_reverse_iterator crend() const noexcept { return rend(); }
[[nodiscard]] constexpr bool empty() const noexcept { return size() == 0; }
[[nodiscard]] constexpr storage_type front() const { return Q_ASSERT(!empty()), m_data[0]; }
[[nodiscard]] constexpr storage_type back() const { return Q_ASSERT(!empty()), m_data[m_size - 1]; }
[[nodiscard]] Q_IMPLICIT operator std::string_view() const noexcept
{ return std::string_view{reinterpret_cast<const char*>(data()), size_t(size())}; }
#ifdef __cpp_lib_char8_t
[[nodiscard]] Q_IMPLICIT operator std::u8string_view() const noexcept
{ return std::u8string_view{utf8(), size_t(size())}; }
#endif
[[nodiscard]] constexpr qsizetype max_size() const noexcept { return maxSize(); }
//
// Qt compatibility API:
//
[[nodiscard]] constexpr bool isNull() const noexcept { return !m_data; }
[[nodiscard]] constexpr bool isEmpty() const noexcept { return empty(); }
[[nodiscard]] constexpr qsizetype length() const noexcept
{ return size(); }
[[nodiscard]] int compare(QBasicUtf8StringView other,
Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
{
return QtPrivate::compareStrings(*this, other, cs);
}
// all defined in qstring.h
[[nodiscard]] inline int compare(QChar other,
Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept;
[[nodiscard]] inline int compare(QStringView other,
Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept;
[[nodiscard]] inline int compare(QLatin1StringView other,
Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept;
[[nodiscard]] inline int compare(const QByteArray &other,
Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept;
[[nodiscard]] inline bool equal(QChar other) const noexcept;
[[nodiscard]] inline bool equal(QStringView other) const noexcept;
[[nodiscard]] inline bool equal(QLatin1StringView other) const noexcept;
[[nodiscard]] inline bool equal(const QByteArray &other) const noexcept;
// end defined in qstring.h
[[nodiscard]] static constexpr qsizetype maxSize() noexcept
{
// -1 to deal with the pointer one-past-the-end;
return QtPrivate::MaxAllocSize - 1;
}
private:
[[nodiscard]] static inline int compare(QBasicUtf8StringView lhs, QBasicUtf8StringView rhs) noexcept
{
return QtPrivate::compareStrings(QBasicUtf8StringView<false>(lhs.data(), lhs.size()),
QBasicUtf8StringView<false>(rhs.data(), rhs.size()));
}
friend bool
comparesEqual(const QBasicUtf8StringView &lhs, const QBasicUtf8StringView &rhs) noexcept
{
return lhs.size() == rhs.size()
&& QtPrivate::equalStrings(QBasicUtf8StringView<false>(lhs.data(), lhs.size()),
QBasicUtf8StringView<false>(rhs.data(), rhs.size()));
}
friend Qt::strong_ordering
compareThreeWay(const QBasicUtf8StringView &lhs, const QBasicUtf8StringView &rhs) noexcept
{
const int res = QBasicUtf8StringView::compare(lhs, rhs);
return Qt::compareThreeWay(res, 0);
}
Q_DECLARE_STRONGLY_ORDERED(QBasicUtf8StringView)
friend bool
comparesEqual(const QBasicUtf8StringView &lhs, const QLatin1StringView &rhs) noexcept
{
return lhs.equal(rhs);
}
friend Qt::strong_ordering
compareThreeWay(const QBasicUtf8StringView &lhs, const QLatin1StringView &rhs) noexcept
{
const int res = lhs.compare(rhs);
return Qt::compareThreeWay(res, 0);
}
Q_DECLARE_STRONGLY_ORDERED(QBasicUtf8StringView, QLatin1StringView)
friend bool
comparesEqual(const QBasicUtf8StringView &lhs, const QStringView &rhs) noexcept
{ return lhs.equal(rhs); }
friend Qt::strong_ordering
compareThreeWay(const QBasicUtf8StringView &lhs, const QStringView &rhs) noexcept
{
const int res = lhs.compare(rhs);
return Qt::compareThreeWay(res, 0);
}
Q_DECLARE_STRONGLY_ORDERED(QBasicUtf8StringView, QStringView)
friend bool comparesEqual(const QBasicUtf8StringView &lhs, const QChar &rhs) noexcept
{ return lhs.equal(rhs); }
friend Qt::strong_ordering
compareThreeWay(const QBasicUtf8StringView &lhs, const QChar &rhs) noexcept
{
const int res = lhs.compare(rhs);
return Qt::compareThreeWay(res, 0);
}
Q_DECLARE_STRONGLY_ORDERED(QBasicUtf8StringView, QChar)
Q_DECLARE_STRONGLY_ORDERED(QBasicUtf8StringView, char16_t)
#if !defined(QT_NO_CAST_FROM_ASCII) && !defined(QT_RESTRICTED_CAST_FROM_ASCII)
friend bool
comparesEqual(const QBasicUtf8StringView &lhs, const QByteArrayView &rhs) noexcept
{
return lhs.size() == rhs.size()
&& QtPrivate::equalStrings(QBasicUtf8StringView<false>(lhs.data(), lhs.size()),
QBasicUtf8StringView<false>(rhs.data(), rhs.size()));
}
friend Qt::strong_ordering
compareThreeWay(const QBasicUtf8StringView &lhs, const QByteArrayView &rhs) noexcept
{
const int res = QtPrivate::compareStrings(QBasicUtf8StringView<false>(lhs.data(), lhs.size()),
QBasicUtf8StringView<false>(rhs.data(), rhs.size()));
return Qt::compareThreeWay(res, 0);
}
Q_DECLARE_STRONGLY_ORDERED(QBasicUtf8StringView, QByteArrayView, QT_ASCII_CAST_WARN)
friend bool
comparesEqual(const QBasicUtf8StringView &lhs, const QByteArray &rhs) noexcept
{
return lhs.equal(rhs);
}
friend Qt::strong_ordering
compareThreeWay(const QBasicUtf8StringView &lhs, const QByteArray &rhs) noexcept
{
const int res = lhs.compare(rhs);
return Qt::compareThreeWay(res, 0);
}
Q_DECLARE_STRONGLY_ORDERED(QBasicUtf8StringView, QByteArray, QT_ASCII_CAST_WARN)
friend bool comparesEqual(const QBasicUtf8StringView &lhs, const char *rhs) noexcept
{ return comparesEqual(lhs, QByteArrayView(rhs)); }
friend Qt::strong_ordering
compareThreeWay(const QBasicUtf8StringView &lhs, const char *rhs) noexcept
{ return compareThreeWay(lhs, QByteArrayView(rhs)); }
Q_DECLARE_STRONGLY_ORDERED(QBasicUtf8StringView, const char *, QT_ASCII_CAST_WARN)
#endif // !defined(QT_NO_CAST_FROM_ASCII) && !defined(QT_RESTRICTED_CAST_FROM_ASCII)
Q_ALWAYS_INLINE constexpr void verify([[maybe_unused]] qsizetype pos = 0,
[[maybe_unused]] qsizetype n = 1) const
{
Q_ASSERT(pos >= 0);
Q_ASSERT(pos <= size());
Q_ASSERT(n >= 0);
Q_ASSERT(n <= size() - pos);
}
const storage_type *m_data;
qsizetype m_size;
};
#ifdef Q_QDOC
#undef QBasicUtf8StringView
#else
template <bool UseChar8T>
Q_DECLARE_TYPEINFO_BODY(QBasicUtf8StringView<UseChar8T>, Q_PRIMITIVE_TYPE);
template <typename QStringLike, std::enable_if_t<std::is_same_v<QStringLike, QByteArray>, bool> = true>
[[nodiscard]] inline q_no_char8_t::QUtf8StringView qToUtf8StringViewIgnoringNull(const QStringLike &s) noexcept
{ return q_no_char8_t::QUtf8StringView(s.begin(), s.size()); }
#endif // Q_QDOC
QT_END_NAMESPACE
#endif /* QUTF8STRINGVIEW_H */