PlayBack-ALSA.h

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/***************************************************************************
        PlayBack-ALSA.h  -  playback device for ALSA
                             -------------------
    begin                : Sat Mar 03 2005
    copyright            : (C) 2005 by Thomas Eschenbacher
    email                : Thomas.Eschenbacher@gmx.de
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/

#ifndef PLAY_BACK_ALSA_H
#define PLAY_BACK_ALSA_H

#include "config.h"
#ifdef HAVE_ALSA_SUPPORT

/*
 * use the new ALSA HW/SW params API, needed to compile under SuSE-9.0
 * (workaround as seen in http://www.linuxjournal.com/article/6735)
 */
#define ALSA_PCM_NEW_HW_PARAMS_API
#define ALSA_PCM_NEW_SW_PARAMS_API

#include <alsa/asoundlib.h>

#include <QList>
#include <QMap>
#include <QString>

#include "libkwave/PlayBackDevice.h"
#include "libkwave/SampleArray.h"

namespace Kwave
{

    class SampleEncoder;

    class PlayBackALSA: public Kwave::PlayBackDevice
    {
    public:

        PlayBackALSA();

        virtual ~PlayBackALSA() Q_DECL_OVERRIDE;

        virtual QString open(const QString &device, double rate,
                             unsigned int channels, unsigned int bits,
                             unsigned int bufbase) Q_DECL_OVERRIDE;

        virtual int write(const Kwave::SampleArray &samples) Q_DECL_OVERRIDE;

        virtual int close() Q_DECL_OVERRIDE;

        virtual QStringList supportedDevices() Q_DECL_OVERRIDE;

        virtual QString fileFilter() Q_DECL_OVERRIDE;

        virtual QList<unsigned int> supportedBits(const QString &device)
            Q_DECL_OVERRIDE;

        virtual int detectChannels(const QString &device,
                                   unsigned int &min, unsigned int &max)
            Q_DECL_OVERRIDE;

    protected:

        snd_pcm_t *openDevice(const QString &device);

        int openDevice(const QString &device, unsigned int rate,
                       unsigned int channels, unsigned int bits);

        int setFormat(snd_pcm_hw_params_t *hw_params, unsigned int bits);

        int flush();

        void scanDevices();

        QString alsaDeviceName(const QString &name);

    private:

        QList<int> detectSupportedFormats(const QString &device);

        int mode2format(int bits);

    private:

        QString m_device_name;

        snd_pcm_t *m_handle;

        double m_rate;

        unsigned int m_channels;

        unsigned int m_bits;

        unsigned int m_bytes_per_sample;

        unsigned int m_bufbase;

        QByteArray m_buffer;

        unsigned int m_buffer_size;

        unsigned int m_buffer_used;

        snd_pcm_format_t m_format;

        snd_pcm_uframes_t m_chunk_size;

        static QMap<QString, QString> m_device_list;

        QList<int> m_supported_formats;

        Kwave::SampleEncoder *m_encoder;

    };
}

#endif /* HAVE_ALSA_SUPPORT */

#endif /* PLAY_BACK_ALSA_H */

//***************************************************************************
//***************************************************************************