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/* audiodevs: Abstraction layer for audio hardware & samples
Copyright (C) 2003-2004 Nemosoft Unv.
This program 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 program 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 program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
For questions, remarks, patches, etc. for this program, the author can be
reached at camstream@smcc.demon.nl.
*/
#ifndef RINGBUFFER_HPP
#define RINGBUFFER_HPP
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <qlist.h>
#include <qobject.h>
#include <qthread.h>
#include "AudioSample.h"
// Forward declarations
class CRingBufferWriter;
class CRingBufferReader;
class CRingBuffer: public QObject
{
friend class CRingBufferWriter;
friend class CRingBufferReader;
Q_OBJECT
private:
QMutex Head; ///< The head-pointer lock
QMutex Lists; ///< For manipulating the lists
QList<CRingBufferWriter> Writers;
QList<CRingBufferReader> Readers;
unsigned int BufferSpace, BufferHead, MaxLength;
void *Buffer;
/* Statistical data */
long BytesWritten; ///< Total amount of bytes put in buffer
int Overflows; ///< Number of times our buffer got full
/* Called by Writers */
void AttachWriter(CRingBufferWriter *s);
void DetachWriter(CRingBufferWriter *s);
int AddToBuffer(void *data, int len, bool must_fit);
int SpaceLeft();
int SpaceUsed();
/* Called by Readers */
void AttachReader(CRingBufferReader *r);
void DetachReader(CRingBufferReader *r);
/* Called by both Readers and Writers */
void Flush();
public:
CRingBuffer(unsigned int buffer_space);
~CRingBuffer();
unsigned int GetBufferLength();
signals:
void ReaderAttached();
void ReaderDetached();
void WriterAttached();
void WriterDetached();
void BufferFlushed();
};
class CRingBufferWriter
{
private:
CRingBuffer *pRing;
CRingBufferWriter(const CRingBufferWriter &) {}; // copies are impossible
public:
CRingBufferWriter(CRingBuffer *ring);
~CRingBufferWriter();
int WriteToBuffer(void *, int len, bool must_fit = false) const;
int SpaceLeft() const;
int SpaceUsed() const;
void Flush() const;
};
class CRingBufferReader: public QObject
{
friend class CRingBuffer;
Q_OBJECT
private:
CRingBuffer *pRing;
QMutex Lock;
QWaitCondition DataReady;
unsigned int BufferTail, MyBufferLength;
unsigned int LowWaterMark, HighWaterMark;
CRingBufferReader(const CRingBufferReader &r) {}; // copies are impossible
public:
CRingBufferReader(CRingBuffer *ring);
~CRingBufferReader();
int SpaceUsed() const;
int ReadFromBufferTail(void *, unsigned int len);
int ReadFromBufferHead(void *, unsigned int len, bool clear = false, unsigned long time = ULONG_MAX);
virtual bool event(QEvent *e); // overloaded
void SetLowWaterMark(unsigned int);
unsigned int GetLowWaterMark() const;
void SetHighWaterMark(unsigned int);
unsigned int GetHighWaterMark() const;
signals:
void DataArrived(int bytes);
void BufferFlushed();
};
#endif
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