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// Copyright (C) 2020 The Qt Company Ltd.
// 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
#include <QtCore/qstring.h>
#ifndef QSTRINGBUILDER_H
#define QSTRINGBUILDER_H
#if 0
// syncqt can not handle the templates in this file, and it doesn't need to
// process them anyway because they are internal.
#pragma qt_class(QStringBuilder)
#pragma qt_sync_stop_processing
#endif
#include <QtCore/qbytearray.h>
#include <string.h>
QT_BEGIN_NAMESPACE
struct Q_CORE_EXPORT QAbstractConcatenable
{
protected:
static void convertFromUtf8(QByteArrayView in, QChar *&out) noexcept;
static inline void convertFromAscii(char a, QChar *&out) noexcept
{
*out++ = QLatin1Char(a);
}
static void appendLatin1To(QLatin1StringView in, QChar *out) noexcept;
};
template <typename T> struct QConcatenable;
template <typename T>
using QConcatenableEx = QConcatenable<q20::remove_cvref_t<T>>;
namespace QtStringBuilder {
template <typename A, typename B> struct ConvertToTypeHelper
{ typedef A ConvertTo; };
template <typename T> struct ConvertToTypeHelper<T, QString>
{ typedef QString ConvertTo; };
template <typename T> using HasIsNull = decltype(std::declval<const T &>().isNull());
template <typename T> bool isNull(const T &t)
{
if constexpr (qxp::is_detected_v<HasIsNull, T>)
return t.isNull();
else
return false;
}
}
template<typename Builder, typename T>
struct QStringBuilderCommon
{
T toUpper() const { return resolved().toUpper(); }
T toLower() const { return resolved().toLower(); }
protected:
T resolved() const { return *static_cast<const Builder*>(this); }
};
template<typename Builder, typename T>
struct QStringBuilderBase : public QStringBuilderCommon<Builder, T>
{
};
template<typename Builder>
struct QStringBuilderBase<Builder, QString> : public QStringBuilderCommon<Builder, QString>
{
QByteArray toLatin1() const { return this->resolved().toLatin1(); }
QByteArray toUtf8() const { return this->resolved().toUtf8(); }
QByteArray toLocal8Bit() const { return this->resolved().toLocal8Bit(); }
};
template <typename A, typename B>
class QStringBuilder : public QStringBuilderBase<QStringBuilder<A, B>,
typename QtStringBuilder::ConvertToTypeHelper<
typename QConcatenableEx<A>::ConvertTo,
typename QConcatenableEx<B>::ConvertTo
>::ConvertTo
>
{
public:
QStringBuilder(A &&a_, B &&b_) : a(std::forward<A>(a_)), b(std::forward<B>(b_)) {}
QStringBuilder(QStringBuilder &&) = default;
QStringBuilder(const QStringBuilder &) = default;
~QStringBuilder() = default;
private:
friend class QByteArray;
friend class QString;
template <typename T> T convertTo() const
{
if (isNull()) {
// appending two null strings must give back a null string,
// so we're special casing this one out, QTBUG-114206
return T();
}
return convertToImpl<T>(Concatenable::size(*this));
}
template <typename T> T convertToImpl(const qsizetype len) const
{
T s(len, Qt::Uninitialized);
// Using data_ptr() here (private API) so we can bypass the
// isDetached() and the replacement of a null pointer with _empty in
// both QString and QByteArray's data() and constData(). The result is
// the same if len != 0.
auto d = reinterpret_cast<typename T::iterator>(s.data_ptr().data());
const auto start = d;
Concatenable::appendTo(*this, d);
if constexpr (Concatenable::ExactSize) {
Q_UNUSED(start)
} else {
if (len != d - start) {
// this resize is necessary since we allocate a bit too much
// when dealing with variable sized 8-bit encodings
s.resize(d - start);
}
}
return s;
}
typedef QConcatenable<QStringBuilder<A, B> > Concatenable;
public:
typedef typename Concatenable::ConvertTo ConvertTo;
operator ConvertTo() const { return convertTo<ConvertTo>(); }
qsizetype size() const { return Concatenable::size(*this); }
bool isNull() const
{
return QtStringBuilder::isNull(a) && QtStringBuilder::isNull(b);
}
A a;
B b;
private:
QStringBuilder &operator=(QStringBuilder &&) = delete;
QStringBuilder &operator=(const QStringBuilder &) = delete;
};
template <> struct QConcatenable<char> : private QAbstractConcatenable
{
typedef char type;
typedef QByteArray ConvertTo;
enum { ExactSize = true };
static qsizetype size(const char) { return 1; }
#ifndef QT_NO_CAST_FROM_ASCII
QT_ASCII_CAST_WARN static inline void appendTo(const char c, QChar *&out)
{
QAbstractConcatenable::convertFromAscii(c, out);
}
#endif
static inline void appendTo(const char c, char *&out)
{ *out++ = c; }
};
template <> struct QConcatenable<QByteArrayView> : private QAbstractConcatenable
{
typedef QByteArrayView type;
typedef QByteArray ConvertTo;
enum { ExactSize = true };
static qsizetype size(QByteArrayView bav) { return bav.size(); }
#ifndef QT_NO_CAST_FROM_ASCII
QT_ASCII_CAST_WARN static inline void appendTo(QByteArrayView bav, QChar *&out)
{
QAbstractConcatenable::convertFromUtf8(bav, out);
}
#endif
static inline void appendTo(QByteArrayView bav, char *&out)
{
qsizetype n = bav.size();
if (n)
memcpy(out, bav.data(), n);
out += n;
}
};
template <> struct QConcatenable<char16_t> : private QAbstractConcatenable
{
typedef char16_t type;
typedef QString ConvertTo;
enum { ExactSize = true };
static constexpr qsizetype size(char16_t) { return 1; }
static inline void appendTo(char16_t c, QChar *&out)
{ *out++ = c; }
};
template <> struct QConcatenable<QLatin1Char>
{
typedef QLatin1Char type;
typedef QString ConvertTo;
enum { ExactSize = true };
static qsizetype size(const QLatin1Char) { return 1; }
static inline void appendTo(const QLatin1Char c, QChar *&out)
{ *out++ = c; }
static inline void appendTo(const QLatin1Char c, char *&out)
{ *out++ = c.toLatin1(); }
};
template <> struct QConcatenable<QChar> : private QAbstractConcatenable
{
typedef QChar type;
typedef QString ConvertTo;
enum { ExactSize = true };
static qsizetype size(const QChar) { return 1; }
static inline void appendTo(const QChar c, QChar *&out)
{ *out++ = c; }
};
template <> struct QConcatenable<QChar::SpecialCharacter> : private QAbstractConcatenable
{
typedef QChar::SpecialCharacter type;
typedef QString ConvertTo;
enum { ExactSize = true };
static qsizetype size(const QChar::SpecialCharacter) { return 1; }
static inline void appendTo(const QChar::SpecialCharacter c, QChar *&out)
{ *out++ = c; }
};
template <> struct QConcatenable<QLatin1StringView> : private QAbstractConcatenable
{
typedef QLatin1StringView type;
typedef QString ConvertTo;
enum { ExactSize = true };
static qsizetype size(const QLatin1StringView a) { return a.size(); }
static inline void appendTo(const QLatin1StringView a, QChar *&out)
{
appendLatin1To(a, out);
out += a.size();
}
static inline void appendTo(const QLatin1StringView a, char *&out)
{
if (const char *data = a.data()) {
memcpy(out, data, a.size());
out += a.size();
}
}
};
template <> struct QConcatenable<QString> : private QAbstractConcatenable
{
typedef QString type;
typedef QString ConvertTo;
enum { ExactSize = true };
static qsizetype size(const QString &a) { return a.size(); }
static inline void appendTo(const QString &a, QChar *&out)
{
const qsizetype n = a.size();
if (n)
memcpy(out, a.data(), sizeof(QChar) * n);
out += n;
}
};
template <> struct QConcatenable<QStringView> : private QAbstractConcatenable
{
typedef QStringView type;
typedef QString ConvertTo;
enum { ExactSize = true };
static qsizetype size(QStringView a) { return a.size(); }
static inline void appendTo(QStringView a, QChar *&out)
{
const auto n = a.size();
if (n)
memcpy(out, a.data(), sizeof(QChar) * n);
out += n;
}
};
template <qsizetype N> struct QConcatenable<const char[N]> : private QAbstractConcatenable
{
typedef const char type[N];
typedef QByteArray ConvertTo;
enum { ExactSize = false };
static qsizetype size(const char[N]) { return N - 1; }
#ifndef QT_NO_CAST_FROM_ASCII
QT_ASCII_CAST_WARN static inline void appendTo(const char a[N], QChar *&out)
{
QAbstractConcatenable::convertFromUtf8(QByteArrayView(a, N - 1), out);
}
#endif
static inline void appendTo(const char a[N], char *&out)
{
while (*a)
*out++ = *a++;
}
};
template <qsizetype N> struct QConcatenable<char[N]> : QConcatenable<const char[N]>
{
typedef char type[N];
};
template <> struct QConcatenable<const char *> : private QAbstractConcatenable
{
typedef const char *type;
typedef QByteArray ConvertTo;
enum { ExactSize = false };
static qsizetype size(const char *a) { return qstrlen(a); }
#ifndef QT_NO_CAST_FROM_ASCII
QT_ASCII_CAST_WARN static inline void appendTo(const char *a, QChar *&out)
{ QAbstractConcatenable::convertFromUtf8(QByteArrayView(a), out); }
#endif
static inline void appendTo(const char *a, char *&out)
{
if (!a)
return;
while (*a)
*out++ = *a++;
}
};
template <> struct QConcatenable<char *> : QConcatenable<const char*>
{
typedef char *type;
};
template <qsizetype N> struct QConcatenable<const char16_t[N]> : private QAbstractConcatenable
{
using type = const char16_t[N];
using ConvertTo = QString;
enum { ExactSize = true };
static qsizetype size(const char16_t[N]) { return N - 1; }
static void appendTo(const char16_t a[N], QChar *&out)
{
memcpy(static_cast<void *>(out), a, (N - 1) * sizeof(char16_t));
out += N - 1;
}
};
template <qsizetype N> struct QConcatenable<char16_t[N]> : QConcatenable<const char16_t[N]>
{
using type = char16_t[N];
};
template <> struct QConcatenable<const char16_t *> : private QAbstractConcatenable
{
using type = const char16_t *;
using ConvertTo = QString;
enum { ExactSize = true };
static qsizetype size(const char16_t *a) { return QStringView(a).size(); }
static inline void appendTo(const char16_t *a, QChar *&out)
{
if (!a)
return;
while (*a)
*out++ = *a++;
}
};
template <> struct QConcatenable<char16_t *> : QConcatenable<const char16_t*>
{
typedef char16_t *type;
};
template <> struct QConcatenable<QByteArray> : private QAbstractConcatenable
{
typedef QByteArray type;
typedef QByteArray ConvertTo;
enum { ExactSize = false };
static qsizetype size(const QByteArray &ba) { return ba.size(); }
#ifndef QT_NO_CAST_FROM_ASCII
QT_ASCII_CAST_WARN static inline void appendTo(const QByteArray &ba, QChar *&out)
{
QAbstractConcatenable::convertFromUtf8(ba, out);
}
#endif
static inline void appendTo(const QByteArray &ba, char *&out)
{
const qsizetype n = ba.size();
if (n)
memcpy(out, ba.begin(), n);
out += n;
}
};
template <typename A, typename B>
struct QConcatenable< QStringBuilder<A, B> >
{
typedef QStringBuilder<A, B> type;
using ConvertTo = typename QtStringBuilder::ConvertToTypeHelper<
typename QConcatenableEx<A>::ConvertTo,
typename QConcatenableEx<B>::ConvertTo
>::ConvertTo;
enum { ExactSize = QConcatenableEx<A>::ExactSize && QConcatenableEx<B>::ExactSize };
static qsizetype size(const type &p)
{
return QConcatenableEx<A>::size(p.a) + QConcatenableEx<B>::size(p.b);
}
template<typename T> static inline void appendTo(const type &p, T *&out)
{
QConcatenableEx<A>::appendTo(p.a, out);
QConcatenableEx<B>::appendTo(p.b, out);
}
};
template <typename A, typename B,
typename = std::void_t<typename QConcatenableEx<A>::type, typename QConcatenableEx<B>::type>>
auto operator%(A &&a, B &&b)
{
return QStringBuilder<A, B>(std::forward<A>(a), std::forward<B>(b));
}
// QT_USE_FAST_OPERATOR_PLUS was introduced in 4.7, QT_USE_QSTRINGBUILDER is to be used from 4.8 onwards
// QT_USE_FAST_OPERATOR_PLUS does not remove the normal operator+ for QByteArray
#if defined(QT_USE_FAST_OPERATOR_PLUS) || defined(QT_USE_QSTRINGBUILDER)
template <typename A, typename B,
typename = std::void_t<typename QConcatenableEx<A>::type, typename QConcatenableEx<B>::type>>
auto operator+(A &&a, B &&b)
{
return std::forward<A>(a) % std::forward<B>(b);
}
#endif
namespace QtStringBuilder {
template <typename A, typename B>
QByteArray &appendToByteArray(QByteArray &a, const QStringBuilder<A, B> &b, char)
{
// append 8-bit data to a byte array
qsizetype len = a.size() + QConcatenable< QStringBuilder<A, B> >::size(b);
a.detach(); // a detach() in a.data() could reset a.capacity() to a.size()
if (len > a.data_ptr().freeSpaceAtEnd()) // capacity() was broken when prepend()-optimization landed
a.reserve(qMax(len, 2 * a.capacity()));
char *it = a.data() + a.size();
QConcatenable< QStringBuilder<A, B> >::appendTo(b, it);
a.resize(len); //we need to resize after the appendTo for the case str+=foo+str
return a;
}
#ifndef QT_NO_CAST_TO_ASCII
template <typename A, typename B>
QByteArray &appendToByteArray(QByteArray &a, const QStringBuilder<A, B> &b, QChar)
{
return a += QString(b).toUtf8();
}
#endif
}
template <typename A, typename B>
QByteArray &operator+=(QByteArray &a, const QStringBuilder<A, B> &b)
{
return QtStringBuilder::appendToByteArray(a, b,
typename QConcatenable< QStringBuilder<A, B> >::ConvertTo::value_type());
}
template <typename A, typename B>
QString &operator+=(QString &a, const QStringBuilder<A, B> &b)
{
qsizetype len = a.size() + QConcatenable< QStringBuilder<A, B> >::size(b);
a.detach(); // a detach() in a.data() could reset a.capacity() to a.size()
if (len > a.data_ptr().freeSpaceAtEnd()) // capacity() was broken when prepend()-optimization landed
a.reserve(qMax(len, 2 * a.capacity()));
QChar *it = a.data() + a.size();
QConcatenable< QStringBuilder<A, B> >::appendTo(b, it);
// we need to resize after the appendTo for the case str+=foo+str
a.resize(it - a.constData()); //may be smaller than len if there was conversion from utf8
return a;
}
QT_END_NAMESPACE
#endif // QSTRINGBUILDER_H