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+/****************************************************************************
+**
+** 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 QBYTEARRAYMATCHER_H
+#define QBYTEARRAYMATCHER_H
+
+#include <QtCore/qbytearray.h>
+
+QT_BEGIN_NAMESPACE
+
+
+class QByteArrayMatcherPrivate;
+
+class Q_CORE_EXPORT QByteArrayMatcher
+{
+public:
+ QByteArrayMatcher();
+ explicit QByteArrayMatcher(const QByteArray &pattern);
+ explicit QByteArrayMatcher(const char *pattern, int length);
+ QByteArrayMatcher(const QByteArrayMatcher &other);
+ ~QByteArrayMatcher();
+
+ QByteArrayMatcher &operator=(const QByteArrayMatcher &other);
+
+ void setPattern(const QByteArray &pattern);
+
+ int indexIn(const QByteArray &ba, int from = 0) const;
+ int indexIn(const char *str, int len, int from = 0) const;
+ inline QByteArray pattern() const
+ {
+ if (q_pattern.isNull())
+ return QByteArray(reinterpret_cast<const char*>(p.p), p.l);
+ return q_pattern;
+ }
+
+private:
+ QByteArrayMatcherPrivate *d;
+ QByteArray q_pattern;
+ struct Data {
+ uchar q_skiptable[256];
+ const uchar *p;
+ int l;
+ };
+ union {
+ uint dummy[256];
+ Data p;
+ };
+};
+
+class QStaticByteArrayMatcherBase
+{
+ Q_DECL_ALIGN(16)
+ struct Skiptable {
+ uchar data[256];
+ } m_skiptable;
+protected:
+ explicit Q_DECL_RELAXED_CONSTEXPR QStaticByteArrayMatcherBase(const char *pattern, uint n) noexcept
+ : m_skiptable(generate(pattern, n)) {}
+ // compiler-generated copy/more ctors/assignment operators are ok!
+ // compiler-generated dtor is ok!
+
+ Q_CORE_EXPORT int indexOfIn(const char *needle, uint nlen, const char *haystack, int hlen, int from) const noexcept;
+
+private:
+ static Q_DECL_RELAXED_CONSTEXPR Skiptable generate(const char *pattern, uint n) noexcept
+ {
+ const auto uchar_max = (std::numeric_limits<uchar>::max)();
+ uchar max = n > uchar_max ? uchar_max : n;
+ Skiptable table = {
+ // this verbose initialization code aims to avoid some opaque error messages
+ // even on powerful compilers such as GCC 5.3. Even though for GCC a loop
+ // format can be found that v5.3 groks, it's probably better to go with this
+ // for the time being:
+ {
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ max, max, max, max, max, max, max, max, max, max, max, max, max, max, max, max,
+ }
+ };
+ pattern += n - max;
+ while (max--)
+ table.data[uchar(*pattern++)] = max;
+ return table;
+ }
+};
+
+template <uint N>
+class QStaticByteArrayMatcher : QStaticByteArrayMatcherBase
+{
+ char m_pattern[N];
+ Q_STATIC_ASSERT_X(N > 2, "QStaticByteArrayMatcher makes no sense for finding a single-char pattern");
+public:
+ explicit Q_DECL_RELAXED_CONSTEXPR QStaticByteArrayMatcher(const char (&patternToMatch)[N]) noexcept
+ : QStaticByteArrayMatcherBase(patternToMatch, N - 1), m_pattern()
+ {
+ for (uint i = 0; i < N; ++i)
+ m_pattern[i] = patternToMatch[i];
+ }
+
+ int indexIn(const QByteArray &haystack, int from = 0) const noexcept
+ { return this->indexOfIn(m_pattern, N - 1, haystack.data(), haystack.size(), from); }
+ int indexIn(const char *haystack, int hlen, int from = 0) const noexcept
+ { return this->indexOfIn(m_pattern, N - 1, haystack, hlen, from); }
+
+ QByteArray pattern() const { return QByteArray(m_pattern, int(N - 1)); }
+};
+
+template <uint N>
+Q_DECL_RELAXED_CONSTEXPR QStaticByteArrayMatcher<N> qMakeStaticByteArrayMatcher(const char (&pattern)[N]) noexcept
+{ return QStaticByteArrayMatcher<N>(pattern); }
+
+QT_END_NAMESPACE
+
+#endif // QBYTEARRAYMATCHER_H
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