AudioAlsa.h

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/*
 * AudioAlsa.h - device-class that implements ALSA-PCM-output
 *
 * Copyright (c) 2004-2009 Tobias Doerffel <tobydox/at/users.sourceforge.net>
 *
 * This file is part of LMMS - https://lmms.io
 *
 * 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 (see COPYING); if not, write to the
 * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301 USA.
 *
 */
 
#ifndef LMMS_AUDIO_ALSA_H
#define LMMS_AUDIO_ALSA_H
 
#include "lmmsconfig.h"
 
#ifdef LMMS_HAVE_ALSA
 
// older ALSA-versions might require this
#define ALSA_PCM_NEW_HW_PARAMS_API
 
#include <alsa/asoundlib.h>
#include <QThread>
 
#include "AudioDevice.h"
 
namespace lmms
{
 
class AudioAlsa : public QThread, public AudioDevice
{
        Q_OBJECT
public:
        class DeviceInfo
        {
        public:
                DeviceInfo(QString const & deviceName, QString const & deviceDescription) :
                        m_deviceName(deviceName),
                        m_deviceDescription(deviceDescription)
                {}
                ~DeviceInfo() = default;
 
                QString const & getDeviceName() const { return m_deviceName; }
                QString const & getDeviceDescription() const { return m_deviceDescription; }
 
        private:
                QString m_deviceName;
                QString m_deviceDescription;
 
        };
 
        using DeviceInfoCollection = std::vector<DeviceInfo>;
 
public:
        AudioAlsa( bool & _success_ful, AudioEngine* audioEngine );
        ~AudioAlsa() override;
 
        inline static QString name()
        {
                return QT_TRANSLATE_NOOP( "AudioDeviceSetupWidget",
                        "ALSA (Advanced Linux Sound Architecture)" );
        }
 
        static QString probeDevice();
 
        static DeviceInfoCollection getAvailableDevices();
 
private:
        void startProcessing() override;
        void stopProcessing() override;
        void run() override;
 
        int setHWParams( const ch_cnt_t _channels, snd_pcm_access_t _access );
        int setSWParams();
        int handleError( int _err );
 
 
        snd_pcm_t * m_handle;
 
        snd_pcm_uframes_t m_bufferSize;
        snd_pcm_uframes_t m_periodSize;
 
        snd_pcm_hw_params_t * m_hwParams;
        snd_pcm_sw_params_t * m_swParams;
 
        bool m_convertEndian;
 
} ;
 
} // namespace lmms
 
#endif // LMMS_HAVE_ALSA
 
#endif // LMMS_AUDIO_ALSA_H