kbufferedio.h

/*
 *  This file is part of the KDE libraries
 *  Copyright (C) 2001 Thiago Macieira <thiago.macieira@kdemail.net>
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Library General Public
 *  License as published by the Free Software Foundation; either
 *  version 2 of the License, or (at your option) any later version.
 *
 *  This library 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
 *  Library General Public License for more details.
 *
 *  You should have received a copy of the GNU Library General Public License
 *  along with this library; see the file COPYING.LIB.  If not, write to
 *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 *  Boston, MA 02110-1301, USA.
 */
 
#ifndef KBUFFEREDIO_H
#define KBUFFEREDIO_H
 
#include <tqcstring.h>
#include <tqptrlist.h>
#include "kasyncio.h"
 
class TDEBufferedIOPrivate;
class TDECORE_EXPORT TDEBufferedIO: public KAsyncIO
{
  TQ_OBJECT
  
 
protected:
  // no default public constructor
  TDEBufferedIO();
 
public:
  enum closeModes
  {
    availRead = 0x01,
    dirtyWrite = 0x02,
    involuntary = 0x10,
    delayed = 0x20,
    closedNow = 0x40
  };

  virtual ~TDEBufferedIO();

  virtual void closeNow() = 0;

  virtual bool setBufferSize(int rsize, int wsize = -2);

  virtual int bytesAvailable() const;

  virtual int waitForMore(int msec) = 0;

  virtual int bytesToWrite() const;

  virtual bool canReadLine() const;
 
  // readBlock, peekBlock and writeBlock are not defined in this class (thus, left
  // pure virtual) because this does not mean only reading and writing
  // to the buffers. It may be necessary to do I/O to complete the
  // transaction (e.g., user wants to read more than is in the buffer).
  // Reading and writing to the buffer are available for access through
  // protected member functions

  virtual int peekBlock(char *data, uint maxlen) = 0;

  virtual int unreadBlock(const char *data, uint len);
 
signals:
  void bytesWritten(int nbytes);
 
  // There is no read signal here. We use the readyRead signal inherited
  // from KAsyncIO for that purpose

  void closed(int state);
 
protected:
  TQPtrList<TQByteArray> inBuf;

  TQPtrList<TQByteArray> outBuf;
 
  unsigned inBufIndex , 
    outBufIndex  ;

  virtual unsigned consumeReadBuffer(unsigned nbytes, char *destbuffer, bool discard = true);

  virtual void consumeWriteBuffer(unsigned nbytes);

  virtual unsigned feedReadBuffer(unsigned nbytes, const char *buffer, bool atBeginning = false);

  virtual unsigned feedWriteBuffer(unsigned nbytes, const char *buffer);

  virtual unsigned readBufferSize() const;

  virtual unsigned writeBufferSize() const;
 
protected:
  virtual void virtual_hook( int id, void* data );
private:
  TDEBufferedIOPrivate *d;
};
 
#endif // KBUFFEREDIO_H