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diff --git a/src/xmlpatterns/acceltree/qcompressedwhitespace.cpp b/src/xmlpatterns/acceltree/qcompressedwhitespace.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+**
+** This file is part of the QtXmlPatterns module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain
+** additional rights. These rights are described in the Nokia Qt LGPL
+** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
+** package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at qt-sales@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QString>
+
+#include "qcompressedwhitespace_p.h"
+
+QT_BEGIN_NAMESPACE
+
+using namespace QPatternist;
+
+CompressedWhitespace::CharIdentifier CompressedWhitespace::toIdentifier(const QChar ch)
+{
+ switch(ch.unicode())
+ {
+ case ' ':
+ return Space;
+ case '\n':
+ return LF;
+ case '\r':
+ return CR;
+ case '\t':
+ return Tab;
+ default:
+ {
+ Q_ASSERT_X(false, Q_FUNC_INFO,
+ "The caller must guarantee only whitespace is passed.");
+ return Tab;
+ }
+ }
+}
+
+bool CompressedWhitespace::isEven(const int number)
+{
+ Q_ASSERT(number >= 0);
+ return number % 2 == 0;
+}
+
+quint8 CompressedWhitespace::toCompressedChar(const QChar ch, const int len)
+{
+ Q_ASSERT(len > 0);
+ Q_ASSERT(len <= MaxCharCount);
+
+ return len + toIdentifier(ch);
+}
+
+QChar CompressedWhitespace::toChar(const CharIdentifier id)
+{
+ switch(id)
+ {
+ case Space: return QLatin1Char(' ');
+ case CR: return QLatin1Char('\r');
+ case LF: return QLatin1Char('\n');
+ case Tab: return QLatin1Char('\t');
+ default:
+ {
+ Q_ASSERT_X(false, Q_FUNC_INFO, "Unexpected input");
+ return QChar();
+ }
+ }
+}
+
+QString CompressedWhitespace::compress(const QStringRef &input)
+{
+ Q_ASSERT(!isEven(1) && isEven(0) && isEven(2));
+ Q_ASSERT(!input.isEmpty());
+
+ QString result;
+ const int len = input.length();
+
+ /* The amount of compressed characters. For instance, if input is
+ * four spaces followed by one tab, compressedChars will be 2, and the resulting
+ * QString will have a length of 1, two compressedChars stored in one QChar. */
+ int compressedChars = 0;
+
+ for(int i = 0; i < len; ++i)
+ {
+ const QChar c(input.at(i));
+
+ int start = i;
+
+ while(true)
+ {
+ if(i + 1 == input.length() || input.at(i + 1) != c)
+ break;
+ else
+ ++i;
+ }
+
+ /* The length of subsequent whitespace characters in the input. */
+ int wsLen = (i - start) + 1;
+
+ /* We might get a sequence of whitespace that is so long, that we can't
+ * store it in one unit/byte. In that case we chop it into as many subsequent
+ * ones that is needed. */
+ while(true)
+ {
+ const int unitLength = qMin(wsLen, int(MaxCharCount));
+ wsLen -= unitLength;
+
+ ushort resultCP = toCompressedChar(c, unitLength);
+
+ if(isEven(compressedChars))
+ result += QChar(resultCP);
+ else
+ {
+ resultCP = resultCP << 8;
+ resultCP |= result.at(result.size() - 1).unicode();
+ result[result.size() - 1] = resultCP;
+ }
+
+ ++compressedChars;
+
+ if(wsLen == 0)
+ break;
+ }
+ }
+
+ return result;
+}
+
+QString CompressedWhitespace::decompress(const QString &input)
+{
+ Q_ASSERT(!input.isEmpty());
+ const int len = input.length() * 2;
+ QString retval;
+
+ for(int i = 0; i < len; ++i)
+ {
+ ushort cp = input.at(i / 2).unicode();
+
+ if(isEven(i))
+ cp &= Lower8Bits;
+ else
+ {
+ cp = cp >> 8;
+
+ if(cp == 0)
+ return retval;
+ }
+
+ const quint8 wsLen = cp & Lower6Bits;
+ const quint8 id = cp & UpperTwoBits;
+
+ /* Resize retval, and fill in on the top. */
+ const int oldSize = retval.size();
+ const int newSize = retval.size() + wsLen;
+ retval.resize(newSize);
+ const QChar ch(toChar(CharIdentifier(id)));
+
+ for(int f = oldSize; f < newSize; ++f)
+ retval[f] = ch;
+ }
+
+ return retval;
+}
+
+QT_END_NAMESPACE
+