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Diffstat (limited to 'src/corelib/tools/qbytedata_p.h')
| -rw-r--r-- | src/corelib/tools/qbytedata_p.h | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/src/corelib/tools/qbytedata_p.h b/src/corelib/tools/qbytedata_p.h new file mode 100644 index 0000000000..45c576d2e9 --- /dev/null +++ b/src/corelib/tools/qbytedata_p.h @@ -0,0 +1,220 @@ +/**************************************************************************** +** +** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). +** All rights reserved. +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the QtCore 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 Technology Preview License Agreement accompanying +** this package. +** +** 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 1.1, included in the file LGPL_EXCEPTION.txt in this package. +** +** If you have questions regarding the use of this file, please contact +** Nokia at qt-info@nokia.com. +** +** +** +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#ifndef QBYTEDATA_H +#define QBYTEDATA_H + +// +// W A R N I N G +// ------------- +// +// This file is not part of the Qt API. It exists purely as an +// implementation detail. This header file may change from version to +// version without notice, or even be removed. +// +// We mean it. +// + +#include <qbytearray.h> + +QT_BEGIN_NAMESPACE + +// this class handles a list of QByteArrays. It is a variant of QRingBuffer +// that avoid malloc/realloc/memcpy. +class QByteDataBuffer +{ +private: + QList<QByteArray> buffers; + qint64 bufferCompleteSize; +public: + QByteDataBuffer() : bufferCompleteSize(0) + { + } + + ~QByteDataBuffer() + { + clear(); + } + + inline void append(QByteDataBuffer& other) + { + if (other.isEmpty()) + return; + + buffers.append(other.buffers); + bufferCompleteSize += other.byteAmount(); + } + + + inline void append(const QByteArray& bd) + { + if (bd.isEmpty()) + return; + + buffers.append(bd); + bufferCompleteSize += bd.size(); + } + + inline void prepend(QByteArray& bd) + { + if (bd.isEmpty()) + return; + + buffers.prepend(bd); + bufferCompleteSize += bd.size(); + } + + // return the first QByteData. User of this function has to qFree() its .data! + // preferably use this function to read data. + inline QByteArray read() + { + bufferCompleteSize -= buffers.first().size(); + return buffers.takeFirst(); + } + + // return everything. User of this function has to qFree() its .data! + // avoid to use this, it might malloc and memcpy. + inline QByteArray readAll() + { + return read(byteAmount()); + } + + // return amount. User of this function has to qFree() its .data! + // avoid to use this, it might malloc and memcpy. + inline QByteArray read(qint64 amount) + { + amount = qMin(byteAmount(), amount); + QByteArray byteData; + byteData.resize(amount); + read(byteData.data(), byteData.size()); + return byteData; + } + + // return amount bytes. User of this function has to qFree() its .data! + // avoid to use this, it will memcpy. + qint64 read(char* dst, qint64 amount) + { + amount = qMin(amount, byteAmount()); + qint64 originalAmount = amount; + char *writeDst = dst; + + while (amount > 0) { + QByteArray first = buffers.takeFirst(); + if (amount >= first.size()) { + // take it completely + bufferCompleteSize -= first.size(); + amount -= first.size(); + memcpy(writeDst, first.constData(), first.size()); + writeDst += first.size(); + first.clear(); + } else { + // take a part of it & it is the last one to take + bufferCompleteSize -= amount; + memcpy(writeDst, first.constData(), amount); + + qint64 newFirstSize = first.size() - amount; + QByteArray newFirstData; + newFirstData.resize(newFirstSize); + memcpy(newFirstData.data(), first.constData() + amount, newFirstSize); + buffers.prepend(newFirstData); + + amount = 0; + first.clear(); + } + } + + return originalAmount; + } + + inline char getChar() + { + char c; + read(&c, 1); + return c; + } + + inline void clear() + { + buffers.clear(); + bufferCompleteSize = 0; + } + + // The byte count of all QByteArrays + inline qint64 byteAmount() const + { + return bufferCompleteSize; + } + + // the number of QByteArrays + inline qint64 bufferCount() const + { + return buffers.length(); + } + + inline bool isEmpty() const + { + return byteAmount() == 0; + } + + inline qint64 sizeNextBlock() const + { + if(buffers.isEmpty()) + return 0; + else + return buffers.first().size(); + } + + inline QByteArray& operator[](int i) + { + return buffers[i]; + } + + inline bool canReadLine() const { + for (int i = 0; i < buffers.length(); i++) + if (buffers.at(i).contains('\n')) + return true; + return false; + } +}; + +QT_END_NAMESPACE + +#endif // QBYTEDATA_H |