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/*
* Copyright (c) 2003, 2004 Michael Pyne <michael.pyne@kdemail.net>
*
* This software is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this library; see the file COPYING.
* If not, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifndef _BSTRING_H
#define _BSTRING_H
#include <qstring.h>
#include <qcstring.h>
#include "bytetape.h"
#include "bbase.h"
/**
* A class to handle the b-encoded strings used by BitTorrent.
* It implements BBase, and although the class is referred to
* as a string, it can hold arbitrary data, since b-encoded strings
* are stored with a length, instead of using a terminator character.
*
* @author Michael Pyne <mpyne@grammarian.homelinux.net>
* @see BBase
*/
class BString : public BBase
{
public:
/**
* Construct a BString from @p dict.
*
* @param dict the buffer to read from
* @param start the position in the buffer to start
* reading from
*/
BString (QByteArray &dict, int start = 0);
/**
* Construct a BString from @p tape. Any changes made to
* @p tape, such as its current position and data, will be
* shared with the object that called this constructor. @p tape
* should already be positioned at the position to read from.
* If construction was successful, @p tape will point to the
* byte after the string data. If construction was unsuccessful,
* the position of the tape is undefined.
*
* @param tape the ByteTape to read from.
*/
BString (ByteTape &tape);
/**
* Destroys the BString, and deallocates all memory that had
* been used.
*/
virtual ~BString ();
/**
* Returns a QString representation of the data in the
* BString. It is the responsibility of the caller to ensure
* that the data is convertible to a QString. More specifically,
* the data should not contain any embedded NULLs.
*
* @return QString containing the data from this BString.
*/
QString get_string() const { return QString::fromUtf8(m_data.data()); }
/**
* Returns the amount of data held by the string. It would be
* perhaps more appropriate to call this size(), since this is
* a buffer, not a true text string.
*
* @return the size of the string, not including the NULL
* terminator.
*/
const int get_len() const { return m_data.size() - 1; }
/**
* Returns the type of this class.
*
* @return bString. This value is only returned by this class.
*/
virtual classID type_id() const { return bString; }
/**
* This function should be called to determine whether the
* string was successfully created, since no exceptions
* are thrown.
*
* @return true if this is a valid string, false otherwise
*/
virtual bool isValid() const { return m_valid; }
/**
* Outputs the b-encoded representation of the object to the given
* QIODevice.
* @param device the QIODevice to write to
* @return true on a successful write, false otherwise
*/
virtual bool writeToDevice (QIODevice &device);
/**
* Changes the value of the string to the given QString.
*
* @param str the QString containing the new value
* @return true if the value was successfully changed,
* false otherwise.
*/
bool setValue (const QString &str);
private:
/**
* This function handles the actual initialization of the object upon
* construction, and set the m_valid flag if successful.
*
* @param tape the ByteTape to read from
*/
void init (ByteTape &tape);
QByteArray m_data;
bool m_valid;
};
#endif /* _BSTRING_H */
// vim: set et ts=4 sw=4:
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