1 files changed, 494 insertions, 0 deletions
diff --git a/src/corelib/text/qstringbuilder.h b/src/corelib/text/qstringbuilder.h
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+++ b/src/corelib/text/qstringbuilder.h
@@ -0,0 +1,494 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#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/qstring.h>
+#include <QtCore/qbytearray.h>
+
+#include <string.h>
+
+QT_BEGIN_NAMESPACE
+
+
+struct Q_CORE_EXPORT QAbstractConcatenable
+{
+protected:
+    static void convertFromAscii(const char *a, int len, QChar *&out) noexcept;
+    static inline void convertFromAscii(char a, QChar *&out) noexcept
+    {
+        *out++ = QLatin1Char(a);
+    }
+    static void appendLatin1To(const char *a, int len, QChar *out) noexcept;
+};
+
+template <typename T> struct QConcatenable {};
+
+namespace QtStringBuilder {
+    template <typename A, typename B> struct ConvertToTypeHelper
+    { typedef A ConvertTo; };
+    template <typename T> struct ConvertToTypeHelper<T, QString>
+    { typedef QString ConvertTo; };
+}
+
+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 QConcatenable<A>::ConvertTo, typename QConcatenable<B>::ConvertTo>::ConvertTo>
+{
+public:
+    QStringBuilder(const A &a_, const B &b_) : a(a_), b(b_) {}
+private:
+    friend class QByteArray;
+    friend class QString;
+    template <typename T> T convertTo() const
+    {
+        const uint len = QConcatenable< QStringBuilder<A, B> >::size(*this);
+        T s(len, Qt::Uninitialized);
+
+        // we abuse const_cast / constData here because we know we've just
+        // allocated the data and we're the only reference count
+        typename T::iterator d = const_cast<typename T::iterator>(s.constData());
+        typename T::const_iterator const start = d;
+        QConcatenable< QStringBuilder<A, B> >::appendTo(*this, d);
+
+        if (!QConcatenable< QStringBuilder<A, B> >::ExactSize && int(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;
+    typedef typename Concatenable::ConvertTo ConvertTo;
+public:
+    operator ConvertTo() const { return convertTo<ConvertTo>(); }
+
+    int size() const { return Concatenable::size(*this); }
+
+    const A &a;
+    const B &b;
+};
+
+template <>
+class QStringBuilder <QString, QString> : public QStringBuilderBase<QStringBuilder<QString, QString>, QString>
+{
+    public:
+        QStringBuilder(const QString &a_, const QString &b_) : a(a_), b(b_) {}
+        QStringBuilder(const QStringBuilder &other) : a(other.a), b(other.b) {}
+
+        operator QString() const
+        { QString r(a); r += b; return r; }
+
+        const QString &a;
+        const QString &b;
+
+    private:
+        QStringBuilder &operator=(const QStringBuilder &) = delete;
+};
+
+template <>
+class QStringBuilder <QByteArray, QByteArray> : public QStringBuilderBase<QStringBuilder<QByteArray, QByteArray>, QByteArray>
+{
+    public:
+        QStringBuilder(const QByteArray &a_, const QByteArray &b_) : a(a_), b(b_) {}
+        QStringBuilder(const QStringBuilder &other) : a(other.a), b(other.b) {}
+
+        operator QByteArray() const
+        { QByteArray r(a); r += b; return r; }
+
+        const QByteArray &a;
+        const QByteArray &b;
+
+    private:
+        QStringBuilder &operator=(const QStringBuilder &) = delete;
+};
+
+
+template <> struct QConcatenable<char> : private QAbstractConcatenable
+{
+    typedef char type;
+    typedef QByteArray ConvertTo;
+    enum { ExactSize = true };
+    static int size(const char) { return 1; }
+#ifndef QT_NO_CAST_FROM_ASCII
+    static inline QT_ASCII_CAST_WARN void appendTo(const char c, QChar *&out)
+    {
+        QAbstractConcatenable::convertFromAscii(c, out);
+    }
+#endif
+    static inline void appendTo(const char c, char *&out)
+    { *out++ = c; }
+};
+
+#if defined(Q_COMPILER_UNICODE_STRINGS)
+template <> struct QConcatenable<char16_t> : private QAbstractConcatenable
+{
+    typedef char16_t type;
+    typedef QString ConvertTo;
+    enum { ExactSize = true };
+    static Q_DECL_CONSTEXPR int size(char16_t) { return 1; }
+    static inline void appendTo(char16_t c, QChar *&out)
+    { *out++ = c; }
+};
+#endif
+
+template <> struct QConcatenable<QLatin1Char>
+{
+    typedef QLatin1Char type;
+    typedef QString ConvertTo;
+    enum { ExactSize = true };
+    static int 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 int 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 int size(const QChar::SpecialCharacter) { return 1; }
+    static inline void appendTo(const QChar::SpecialCharacter c, QChar *&out)
+    { *out++ = c; }
+};
+
+template <> struct QConcatenable<QCharRef> : private QAbstractConcatenable
+{
+    typedef QCharRef type;
+    typedef QString ConvertTo;
+    enum { ExactSize = true };
+    static int size(QCharRef) { return 1; }
+    static inline void appendTo(QCharRef c, QChar *&out)
+    { *out++ = QChar(c); }
+};
+
+template <> struct QConcatenable<QLatin1String> : private QAbstractConcatenable
+{
+    typedef QLatin1String type;
+    typedef QString ConvertTo;
+    enum { ExactSize = true };
+    static int size(const QLatin1String a) { return a.size(); }
+    static inline void appendTo(const QLatin1String a, QChar *&out)
+    {
+        appendLatin1To(a.latin1(), a.size(), out);
+        out += a.size();
+    }
+    static inline void appendTo(const QLatin1String 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 int size(const QString &a) { return a.size(); }
+    static inline void appendTo(const QString &a, QChar *&out)
+    {
+        const int n = a.size();
+        memcpy(out, reinterpret_cast<const char*>(a.constData()), sizeof(QChar) * n);
+        out += n;
+    }
+};
+
+template <> struct QConcatenable<QStringRef> : private QAbstractConcatenable
+{
+    typedef QStringRef type;
+    typedef QString ConvertTo;
+    enum { ExactSize = true };
+    static int size(const QStringRef &a) { return a.size(); }
+    static inline void appendTo(const QStringRef &a, QChar *&out)
+    {
+        const int n = a.size();
+        memcpy(out, reinterpret_cast<const char*>(a.constData()), sizeof(QChar) * n);
+        out += n;
+    }
+};
+
+template <> struct QConcatenable<QStringView> : private QAbstractConcatenable
+{
+    typedef QStringView type;
+    typedef QString ConvertTo;
+    enum { ExactSize = true };
+    static int size(QStringView a) { return a.length(); }
+    static inline void appendTo(QStringView a, QChar *&out)
+    {
+        const auto n = a.size();
+        memcpy(out, a.data(), sizeof(QChar) * n);
+        out += n;
+    }
+};
+
+template <int N> struct QConcatenable<const char[N]> : private QAbstractConcatenable
+{
+    typedef const char type[N];
+    typedef QByteArray ConvertTo;
+    enum { ExactSize = false };
+    static int size(const char[N]) { return N - 1; }
+#ifndef QT_NO_CAST_FROM_ASCII
+    static inline void QT_ASCII_CAST_WARN appendTo(const char a[N], QChar *&out)
+    {
+        QAbstractConcatenable::convertFromAscii(a, N - 1, out);
+    }
+#endif
+    static inline void appendTo(const char a[N], char *&out)
+    {
+        while (*a)
+            *out++ = *a++;
+    }
+};
+
+template <int 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 int size(const char *a) { return qstrlen(a); }
+#ifndef QT_NO_CAST_FROM_ASCII
+    static inline void QT_ASCII_CAST_WARN appendTo(const char *a, QChar *&out)
+    { QAbstractConcatenable::convertFromAscii(a, -1, 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;
+};
+
+#if defined(Q_COMPILER_UNICODE_STRINGS)
+template <int N> struct QConcatenable<const char16_t[N]> : private QAbstractConcatenable
+{
+    using type = const char16_t[N];
+    using ConvertTo = QString;
+    enum { ExactSize = true };
+    static int size(const char16_t[N]) { return N - 1; }
+    static void appendTo(const char16_t a[N], QChar *&out)
+    {
+        memcpy(out, a, (N - 1) * sizeof(char16_t));
+        out += N - 1;
+    }
+};
+
+template <int 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 int size(const char16_t *a) { return QStringView(a).length(); };
+    static inline void QT_ASCII_CAST_WARN 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;
+};
+#endif // UNICODE_STRINGS
+
+template <> struct QConcatenable<QByteArray> : private QAbstractConcatenable
+{
+    typedef QByteArray type;
+    typedef QByteArray ConvertTo;
+    enum { ExactSize = false };
+    static int size(const QByteArray &ba) { return ba.size(); }
+#ifndef QT_NO_CAST_FROM_ASCII
+    static inline QT_ASCII_CAST_WARN void appendTo(const QByteArray &ba, QChar *&out)
+    {
+        QAbstractConcatenable::convertFromAscii(ba.constData(), ba.size(), out);
+    }
+#endif
+    static inline void appendTo(const QByteArray &ba, char *&out)
+    {
+        const char *a = ba.constData();
+        const char * const end = ba.end();
+        while (a != end)
+            *out++ = *a++;
+    }
+};
+
+
+template <typename A, typename B>
+struct QConcatenable< QStringBuilder<A, B> >
+{
+    typedef QStringBuilder<A, B> type;
+    typedef typename QtStringBuilder::ConvertToTypeHelper<typename QConcatenable<A>::ConvertTo, typename QConcatenable<B>::ConvertTo>::ConvertTo ConvertTo;
+    enum { ExactSize = QConcatenable<A>::ExactSize && QConcatenable<B>::ExactSize };
+    static int size(const type &p)
+    {
+        return QConcatenable<A>::size(p.a) + QConcatenable<B>::size(p.b);
+    }
+    template<typename T> static inline void appendTo(const type &p, T *&out)
+    {
+        QConcatenable<A>::appendTo(p.a, out);
+        QConcatenable<B>::appendTo(p.b, out);
+    }
+};
+
+template <typename A, typename B>
+QStringBuilder<typename QConcatenable<A>::type, typename QConcatenable<B>::type>
+operator%(const A &a, const B &b)
+{
+   return QStringBuilder<typename QConcatenable<A>::type, typename QConcatenable<B>::type>(a, 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>
+QStringBuilder<typename QConcatenable<A>::type, typename QConcatenable<B>::type>
+operator+(const A &a, const B &b)
+{
+   return QStringBuilder<typename QConcatenable<A>::type, typename QConcatenable<B>::type>(a, 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
+    int len = a.size() + QConcatenable< QStringBuilder<A, B> >::size(b);
+    a.reserve(len);
+    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)
+{
+    int len = a.size() + QConcatenable< QStringBuilder<A, B> >::size(b);
+    a.reserve(len);
+    QChar *it = a.data() + a.size();
+    QConcatenable< QStringBuilder<A, B> >::appendTo(b, it);
+    a.resize(int(it - a.constData())); //may be smaller than len if there was conversion from utf8
+    return a;
+}
+
+
+QT_END_NAMESPACE
+
+#endif // QSTRINGBUILDER_H