audiooutputca.cpp

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/*****************************************************************************
 * = NAME
 * audiooutputca.cpp
 *
 * = DESCRIPTION
 * Core Audio glue for Mac OS X.
 *
 * = REVISION
 * $Id$
 *
 * = AUTHORS
 * Jeremiah Morris, Andrew Kimpton, Nigel Pearson, Jean-Yves Avenard
 *****************************************************************************/

#include <array>
#include <vector>

#include <CoreServices/CoreServices.h>
#include <CoreAudio/CoreAudio.h>
#include <AudioUnit/AudioUnit.h>
#include <AudioToolbox/AudioFormat.h>

#include "mythcorecontext.h"
#include "audiooutputca.h"
#include "config.h"
#include "SoundTouch.h"

#define LOC QString("CoreAudio: ")

#define CHANNELS_MIN 1
#define CHANNELS_MAX 8

using AudioStreamIDVec = std::vector<AudioStreamID>;
using AudioStreamRangedVec = std::vector<AudioStreamRangedDescription>;
using AudioValueRangeVec = std::vector<AudioValueRange>;
using RatesVec = std::vector<int>;
using ChannelsArr = std::array<bool,CHANNELS_MAX>;

#define OSS_STATUS(x) UInt32ToFourCC((UInt32*)&(x))
char* UInt32ToFourCC(const UInt32* pVal)
{
    UInt32 inVal = *pVal;
    char* pIn = (char*)&inVal;
    static char fourCC[5];
    fourCC[4] = 0;
    fourCC[3] = pIn[0];
    fourCC[2] = pIn[1];
    fourCC[1] = pIn[2];
    fourCC[0] = pIn[3];
    return fourCC;
}

QString StreamDescriptionToString(AudioStreamBasicDescription desc)
{
    UInt32 formatId = desc.mFormatID;
    char* fourCC = UInt32ToFourCC(&formatId);
    QString str;

    switch (desc.mFormatID)
    {
        case kAudioFormatLinearPCM:
            str = QString("[%1] %2%3 Channel %4-bit %5 %6 (%7Hz)")
            .arg(fourCC)
            .arg((desc.mFormatFlags & kAudioFormatFlagIsNonMixable) ? "" : "Mixable ")
            .arg(desc.mChannelsPerFrame)
            .arg(desc.mBitsPerChannel)
            .arg((desc.mFormatFlags & kAudioFormatFlagIsFloat) ? "Floating Point" : "Signed Integer")
            .arg((desc.mFormatFlags & kAudioFormatFlagIsBigEndian) ? "BE" : "LE")
            .arg((UInt32)desc.mSampleRate);
            break;
        case kAudioFormatAC3:
            str = QString("[%1] AC-3/DTS (%2Hz)")
            .arg(fourCC)
            .arg((UInt32)desc.mSampleRate);
            break;
        case kAudioFormat60958AC3:
            str = QString("[%1] AC-3/DTS for S/PDIF %2 (%3Hz)")
            .arg(fourCC)
            .arg((desc.mFormatFlags & kAudioFormatFlagIsBigEndian) ? "BE" : "LE")
            .arg((UInt32)desc.mSampleRate);
            break;
        default:
            str = QString("[%1]").arg(fourCC);
            break;
    }
    return str;
}

class CoreAudioData {
public:
    explicit CoreAudioData(AudioOutputCA *parent);
    CoreAudioData(AudioOutputCA *parent, AudioDeviceID deviceID);
    CoreAudioData(AudioOutputCA *parent, QString deviceName);

    static AudioDeviceID GetDefaultOutputDevice();
    int  GetTotalOutputChannels();
    QString *GetName();
    static AudioDeviceID GetDeviceWithName(const QString& deviceName);

    bool OpenDevice();
    int  OpenAnalog();
    void CloseAnalog();
    bool OpenSPDIF ();
    void CloseSPDIF();

    static void SetAutoHogMode(bool enable);
    static bool GetAutoHogMode();
    static pid_t GetHogStatus();
    bool SetHogStatus(bool hog);
    bool SetMixingSupport(bool mix);
    bool GetMixingSupport();

    bool FindAC3Stream();
    static void ResetAudioDevices();
    static void ResetStream(AudioStreamID s);
    static RatesVec RatesList(AudioDeviceID d);
    bool ChannelsList(AudioDeviceID d, bool passthru, ChannelsArr& chans);

    static AudioStreamIDVec      StreamsList(AudioDeviceID d);
    static AudioStreamRangedVec  FormatsList(AudioStreamID s);

    static int  AudioStreamChangeFormat(AudioStreamID               s,
                                 AudioStreamBasicDescription format);

    // TODO: Convert these to macros!
    static void Debug(const QString& msg)
    {   LOG(VB_AUDIO, LOG_INFO,      "CoreAudioData::" + msg);   }

    static void Error(const QString& msg)
    {    LOG(VB_GENERAL, LOG_ERR, "CoreAudioData Error:" + msg);   }

    static void Warn (const QString& msg)
    {    LOG(VB_GENERAL, LOG_WARNING, "CoreAudioData Warning:" + msg);   }

    AudioOutputCA  *mCA            {nullptr}; // We could subclass, but this ends up tidier

    // Analog output specific
    AudioUnit      mOutputUnit     {nullptr};

    // SPDIF mode specific
    bool           mDigitalInUse   {false};   // Is the digital (SPDIF) output in use?
    pid_t          mHog            {-1};
    int            mMixerRestore   {-1};
    AudioDeviceID  mDeviceID       {0};
    AudioStreamID  mStreamID       {};      // StreamID that has a cac3 streamformat
    int            mStreamIndex    {-1};    // Index of mStreamID in an AudioBufferList
    UInt32         mBytesPerPacket {UINT32_MAX};
    AudioStreamBasicDescription mFormatOrig {}; // The original format the stream
    AudioStreamBasicDescription mFormatNew  {}; // The format we changed the stream to
    bool           mRevertFormat  {false};  // Do we need to revert the stream format?
    bool           mIoProc        {false};
    bool           mInitialized   {false};
    bool           mStarted       {false};
    bool           mWasDigital    {false};
    AudioDeviceIOProcID mIoProcID {};
};

// These callbacks communicate with Core Audio.
static OSStatus RenderCallbackAnalog(void                       *inRefCon,
                                     AudioUnitRenderActionFlags *ioActionFlags,
                                     const AudioTimeStamp       *inTimeStamp,
                                     UInt32                     inBusNumber,
                                     UInt32                     inNumberFrames,
                                     AudioBufferList            *ioData);
static OSStatus RenderCallbackSPDIF(AudioDeviceID        inDevice,
                                    const AudioTimeStamp *inNow,
                                    const void           *inInputData,
                                    const AudioTimeStamp *inInputTime,
                                    AudioBufferList      *outOutputData,
                                    const AudioTimeStamp *inOutputTime,
                                    void                 *inRefCon);

AudioOutputCA::AudioOutputCA(const AudioSettings &settings) :
AudioOutputBase(settings)
{
    m_mainDevice.remove(0, 10);
    VBAUDIO(QString("AudioOutputCA::AudioOutputCA searching %1").arg(m_mainDevice));
    d = new CoreAudioData(this, m_mainDevice);

    InitSettings(settings);
    if (settings.m_init)
        Reconfigure(settings);
}

AudioOutputCA::~AudioOutputCA()
{
    KillAudio();

    delete d;
}

AudioOutputSettings* AudioOutputCA::GetOutputSettings(bool digital)
{
    auto *settings = new AudioOutputSettings();

    // Seek hardware sample rate available
    RatesVec rates = CoreAudioData::RatesList(d->mDeviceID);

    if (rates.empty())
    {
        // Error retrieving rates, assume 48kHz
        settings->AddSupportedRate(48000);
    }
    else
    {
        while (int rate = settings->GetNextRate())
        {
            for (auto entry : rates)
            {
                if (entry != rate)
                    continue;
                settings->AddSupportedRate(entry);
            }
        }
    }

    // Supported format: 16 bits audio or float
    settings->AddSupportedFormat(FORMAT_S16);
    settings->AddSupportedFormat(FORMAT_FLT);

    ChannelsArr channels {};
    if (!d->ChannelsList(d->mDeviceID, digital, channels))
    {
        // Error retrieving list of supported channels, assume stereo only
        settings->AddSupportedChannels(2);
    }
    else
    {
        for (int i = CHANNELS_MIN; i <= CHANNELS_MAX; i++)
        {
            if (channels[i])
            {
                Debug(QString("Support %1 channels").arg(i));
                // In case 8 channels are supported but not 6, fake 6
                if (i == 8 && !channels[6])
                    settings->AddSupportedChannels(6);
                settings->AddSupportedChannels(i);
            }
        }
    }

    if (d->FindAC3Stream())
    {
        settings->setPassthrough(1); // yes passthrough
    }
    return settings;
}

bool AudioOutputCA::OpenDevice()
{
    bool deviceOpened = false;

    if (d->mWasDigital)
    {
    }
    Debug("OpenDevice: Entering");
    if (m_passthru || m_enc)
    {
        Debug("OpenDevice() Trying Digital.");
        if (!(deviceOpened = d->OpenSPDIF()))
            d->CloseSPDIF();
    }

    if (!deviceOpened)
    {
        Debug("OpenDevice() Trying Analog.");
        int result = -1;
        //for (int i=0; result < 0 && i < 10; i++)
        {
            result = d->OpenAnalog();
            Debug(QString("OpenDevice: OpenAnalog = %1").arg(result));
            if (result < 0)
            {
                d->CloseAnalog();
                usleep((1000 * 1000) - 1); // Argument to usleep must be less than 1 million
            }
        }
        deviceOpened = (result > 0);
    }

    if (!deviceOpened)
    {
        Error("Couldn't open any audio device!");
        d->CloseAnalog();
        return false;
    }

    if (m_internalVol && m_setInitialVol)
    {
        QString controlLabel = gCoreContext->GetSetting("MixerControl", "PCM");
        controlLabel += "MixerVolume";
        SetCurrentVolume(gCoreContext->GetNumSetting(controlLabel, 80));
    }

    return true;
}

void AudioOutputCA::CloseDevice()
{
    VBAUDIO(QString("CloseDevice [%1]: Entering")
            .arg(d->mDigitalInUse ? "SPDIF" : "Analog"));
    if (d->mDigitalInUse)
        d->CloseSPDIF();
    else
        d->CloseAnalog();
}

template <class AudioDataType>
static inline void _ReorderSmpteToCA(AudioDataType *buf, uint frames)
{
    AudioDataType tmpLS;
    AudioDataType tmpRS;
    AudioDataType tmpRLs;
    AudioDataType tmpRRs;
    AudioDataType *buf2;
    for (uint i = 0; i < frames; i++)
    {
        buf = buf2 = buf + 4;
        tmpRLs = *buf++;
        tmpRRs = *buf++;
        tmpLS = *buf++;
        tmpRS = *buf++;

        *buf2++ = tmpLS;
        *buf2++ = tmpRS;
        *buf2++ = tmpRLs;
        *buf2++ = tmpRRs;
    }
}

static inline void ReorderSmpteToCA(void *buf, uint frames, AudioFormat format)
{
    switch(AudioOutputSettings::FormatToBits(format))
    {
        case  8: _ReorderSmpteToCA((uchar *)buf, frames); break;
        case 16: _ReorderSmpteToCA((short *)buf, frames); break;
        default: _ReorderSmpteToCA((int   *)buf, frames); break;
    }
}

bool AudioOutputCA::RenderAudio(unsigned char *aubuf,
                                int size, unsigned long long timestamp)
{
    if (m_pauseAudio || m_killAudio)
    {
        m_actuallyPaused = true;
        return false;
    }

    /* This callback is called when the sound system requests
     data.  We don't want to block here, because that would
     just cause dropouts anyway, so we always return whatever
     data is available.  If we haven't received enough, either
     because we've finished playing or we have a buffer
     underrun, we play silence to fill the unused space.  */

    int written_size = GetAudioData(aubuf, size, false);
    if (written_size && (size > written_size))
    {
        // play silence on buffer underrun
        memset(aubuf + written_size, 0, size - written_size);
    }

    //Audio received is in SMPTE channel order, reorder to CA unless passthru
    if (!m_passthru && m_channels == 8)
    {
        ReorderSmpteToCA(aubuf, size / m_outputBytesPerFrame, m_outputFormat);
    }

    /* update audiotime (m_bufferedBytes is read by GetBufferedOnSoundcard) */
    UInt64 nanos = AudioConvertHostTimeToNanos(timestamp -
                                               AudioGetCurrentHostTime());
    m_bufferedBytes = (int)((nanos / 1000000000.0) *  // secs
                            (m_effDsp / 100.0) *      // frames/sec
                            m_outputBytesPerFrame);   // bytes/frame

    return (written_size > 0);
}

// unneeded and unused in CA
void AudioOutputCA::WriteAudio(unsigned char *aubuf, int size)
{
    (void)aubuf;
    (void)size;
}

int AudioOutputCA::GetBufferedOnSoundcard(void) const
{
    return m_bufferedBytes;
}

int64_t AudioOutputCA::GetAudiotime(void)
{
    int audbuf_timecode = GetBaseAudBufTimeCode();

    if (!audbuf_timecode)
        return 0;

    int totalbuffer = audioready() + GetBufferedOnSoundcard();

    return audbuf_timecode - (int)(totalbuffer * 100000.0 /
                                   (m_outputBytesPerFrame *
                                    m_effDsp * m_stretchFactor));
}

/* This callback provides converted audio data to the default output device. */
OSStatus RenderCallbackAnalog(void                       *inRefCon,
                              AudioUnitRenderActionFlags *ioActionFlags,
                              const AudioTimeStamp       *inTimeStamp,
                              UInt32                     inBusNumber,
                              UInt32                     inNumberFrames,
                              AudioBufferList            *ioData)
{
    (void)inBusNumber;
    (void)inNumberFrames;

    AudioOutputCA *inst = (static_cast<CoreAudioData *>(inRefCon))->mCA;

    if (!inst->RenderAudio((unsigned char *)(ioData->mBuffers[0].mData),
                           ioData->mBuffers[0].mDataByteSize,
                           inTimeStamp->mHostTime))
    {
        // play silence if RenderAudio returns false
        memset(ioData->mBuffers[0].mData, 0, ioData->mBuffers[0].mDataByteSize);
        *ioActionFlags = kAudioUnitRenderAction_OutputIsSilence;
    }
    return noErr;
}

int AudioOutputCA::GetVolumeChannel(int channel) const
{
    // FIXME: this only returns global volume
    (void)channel;
    Float32 volume;

    if (!AudioUnitGetParameter(d->mOutputUnit,
                               kHALOutputParam_Volume,
                               kAudioUnitScope_Global, 0, &volume))
        return (int)lroundf(volume * 100.0F);

    return 0;    // error case
}

void AudioOutputCA::SetVolumeChannel(int channel, int volume)
{
    // FIXME: this only sets global volume
    (void)channel;
    AudioUnitSetParameter(d->mOutputUnit, kHALOutputParam_Volume,
                          kAudioUnitScope_Global, 0, (volume * 0.01F), 0);
}

// IOProc style callback for SPDIF audio output
static OSStatus RenderCallbackSPDIF(AudioDeviceID        inDevice,
                                    const AudioTimeStamp *inNow,
                                    const void           *inInputData,
                                    const AudioTimeStamp *inInputTime,
                                    AudioBufferList      *outOutputData,
                                    const AudioTimeStamp *inOutputTime,
                                    void                 *inRefCon)
{
    auto *d = static_cast<CoreAudioData *>(inRefCon);
    AudioOutputCA    *a = d->mCA;
    int           index = d->mStreamIndex;

    (void)inDevice;     // unused
    (void)inNow;        // unused
    (void)inInputData;  // unused
    (void)inInputTime;  // unused

    /*
     * HACK: No idea why this would be the case, but after the second run, we get
     * incorrect value
     */
    if (d->mBytesPerPacket > 0 &&
        outOutputData->mBuffers[index].mDataByteSize > d->mBytesPerPacket)
    {
        outOutputData->mBuffers[index].mDataByteSize = d->mBytesPerPacket;
    }
    if (!a->RenderAudio((unsigned char *)(outOutputData->mBuffers[index].mData),
                        outOutputData->mBuffers[index].mDataByteSize,
                        inOutputTime->mHostTime))
    {
        // play silence if RenderAudio returns false
        memset(outOutputData->mBuffers[index].mData, 0,
              outOutputData->mBuffers[index].mDataByteSize);
    }
    return noErr;
}

CoreAudioData::CoreAudioData(AudioOutputCA *parent) : mCA(parent)
{
    // Reset all the devices to a default 'non-hog' and mixable format.
    // If we don't do this we may be unable to find the Default Output device.
    // (e.g. if we crashed last time leaving it stuck in AC-3 mode)
    ResetAudioDevices();

    mDeviceID = GetDefaultOutputDevice();
}

CoreAudioData::CoreAudioData(AudioOutputCA *parent, AudioDeviceID deviceID) :
    mCA(parent)
{
    ResetAudioDevices();
    mDeviceID = deviceID;
}

CoreAudioData::CoreAudioData(AudioOutputCA *parent, QString deviceName) :
    mCA(parent)
{
    ResetAudioDevices();
    mDeviceID = GetDeviceWithName(deviceName);
    if (!mDeviceID)
    {
        // Didn't find specified device, use default one
        mDeviceID = GetDefaultOutputDevice();
        if (deviceName != "Default Output Device")
        {
            Warn(QString("CoreAudioData: \"%1\" not found, using default device %2.")
                 .arg(deviceName).arg(mDeviceID));
        }
    }
    Debug(QString("CoreAudioData: device number is %1")
          .arg(mDeviceID));
}

AudioDeviceID CoreAudioData::GetDeviceWithName(const QString &deviceName)
{
    UInt32 size = 0;
    AudioDeviceID deviceID = 0;
    AudioObjectPropertyAddress pa
    {
        kAudioHardwarePropertyDevices,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    OSStatus err = AudioObjectGetPropertyDataSize(kAudioObjectSystemObject, &pa,
                                                  0, nullptr, &size);
    if (err)
    {
        Warn(QString("GetPropertyDataSize: Unable to retrieve the property sizes. "
                     "Error [%1]")
             .arg(err));
        return deviceID;
    }

    UInt32 deviceCount = size / sizeof(AudioDeviceID);
    auto* pDevices = new AudioDeviceID[deviceCount];

    err = AudioObjectGetPropertyData(kAudioObjectSystemObject, &pa,
                                     0, nullptr, &size, pDevices);
    if (err)
    {
        Warn(QString("GetDeviceWithName: Unable to retrieve the list of available devices. "
                     "Error [%1]")
             .arg(err));
    }
    else
    {
        for (UInt32 dev = 0; dev < deviceCount; dev++)
        {
            CoreAudioData device(nullptr, pDevices[dev]);
            if (device.GetTotalOutputChannels() == 0)
                continue;
            QString *name = device.GetName();
            if (name && name == deviceName)
            {
                Debug(QString("GetDeviceWithName: Found: %1").arg(*name));
                deviceID = pDevices[dev];
                delete name;
            }
            if (deviceID)
                break;
        }
    }
    delete[] pDevices;
    return deviceID;
}

AudioDeviceID CoreAudioData::GetDefaultOutputDevice()
{
    UInt32        paramSize;
    AudioDeviceID deviceId = 0;
    AudioObjectPropertyAddress pa
    {
        kAudioHardwarePropertyDefaultOutputDevice,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    // Find the ID of the default Device
    paramSize = sizeof(deviceId);
    OSStatus err = AudioObjectGetPropertyData(kAudioObjectSystemObject, &pa,
                                              0, nullptr, &paramSize, &deviceId);
    if (err == noErr)
        Debug(QString("GetDefaultOutputDevice: default device ID = %1").arg(deviceId));
    else
    {
        Warn(QString("GetDefaultOutputDevice: could not get default audio device: [%1]")
             .arg(OSS_STATUS(err)));
        deviceId = 0;
    }
    return deviceId;
}

int CoreAudioData::GetTotalOutputChannels()
{
    if (!mDeviceID)
        return 0;
    UInt32 channels = 0;
    UInt32 size = 0;
    AudioObjectPropertyAddress pa
    {
        kAudioDevicePropertyStreamConfiguration,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    OSStatus err = AudioObjectGetPropertyDataSize(mDeviceID, &pa,
                                                  0, nullptr, &size);
    if (err)
    {
        Warn(QString("GetTotalOutputChannels: Unable to get "
                     "size of device output channels - id: %1 Error = [%2]")
             .arg(mDeviceID)
             .arg(err));
        return 0;
    }

    auto *pList = (AudioBufferList *)malloc(size);
    err = AudioObjectGetPropertyData(mDeviceID, &pa,
                                     0, nullptr, &size, pList);
    if (!err)
    {
        for (UInt32 buffer = 0; buffer < pList->mNumberBuffers; buffer++)
            channels += pList->mBuffers[buffer].mNumberChannels;
    }
    else
    {
        Warn(QString("GetTotalOutputChannels: Unable to get "
                     "total device output channels - id: %1 Error = [%2]")
             .arg(mDeviceID)
             .arg(err));
    }
    Debug(QString("GetTotalOutputChannels: Found %1 channels in %2 buffers")
          .arg(channels).arg(pList->mNumberBuffers));
    free(pList);
    return channels;
}

QString *CoreAudioData::GetName()
{
    if (!mDeviceID)
        return nullptr;

    AudioObjectPropertyAddress pa
    {
        kAudioObjectPropertyName,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    CFStringRef name;
    UInt32 propertySize = sizeof(CFStringRef);
    OSStatus err = AudioObjectGetPropertyData(mDeviceID, &pa,
                                              0, nullptr, &propertySize, &name);
    if (err)
    {
        Error(QString("AudioObjectGetPropertyData for kAudioObjectPropertyName error: [%1]")
              .arg(err));
        return nullptr;
    }
    char *cname = new char[CFStringGetLength(name) + 1];
    CFStringGetCString(name, cname, CFStringGetLength(name) + 1, kCFStringEncodingUTF8);
    auto *qname = new QString(cname);
    delete[] cname;
    return qname;
}

bool CoreAudioData::GetAutoHogMode()
{
    UInt32 val = 0;
    UInt32 size = sizeof(val);
    AudioObjectPropertyAddress pa
    {
        kAudioHardwarePropertyHogModeIsAllowed,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    OSStatus err = AudioObjectGetPropertyData(kAudioObjectSystemObject, &pa, 0, nullptr, &size, &val);
    if (err)
    {
        Warn(QString("GetAutoHogMode: Unable to get auto 'hog' mode. Error = [%1]")
             .arg(err));
        return false;
    }
    return (val == 1);
}

void CoreAudioData::SetAutoHogMode(bool enable)
{
    UInt32 val = enable ? 1 : 0;
    AudioObjectPropertyAddress pa
    {
        kAudioHardwarePropertyHogModeIsAllowed,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    OSStatus err = AudioObjectSetPropertyData(kAudioObjectSystemObject, &pa, 0, nullptr,
                                              sizeof(val), &val);
    if (err)
    {
        Warn(QString("SetAutoHogMode: Unable to set auto 'hog' mode. Error = [%1]")
             .arg(err));
    }
}

pid_t CoreAudioData::GetHogStatus()
{
    pid_t PID;
    UInt32 PIDsize = sizeof(PID);
    AudioObjectPropertyAddress pa
    {
        kAudioDevicePropertyHogMode,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    OSStatus err = AudioObjectGetPropertyData(kAudioObjectSystemObject, &pa, 0, nullptr,
                                 &PIDsize, &PID);
    if (err != noErr)
    {
        // This is not a fatal error.
        // Some drivers simply don't support this property
        Debug(QString("GetHogStatus: unable to check: [%1]")
              .arg(err));
        return -1;
    }
    return PID;
}

bool CoreAudioData::SetHogStatus(bool hog)
{
    AudioObjectPropertyAddress pa
    {
        kAudioDevicePropertyHogMode,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    // According to Jeff Moore (Core Audio, Apple), Setting kAudioDevicePropertyHogMode
    // is a toggle and the only way to tell if you do get hog mode is to compare
    // the returned pid against getpid, if the match, you have hog mode, if not you don't.
    if (!mDeviceID)
        return false;

    if (hog)
    {
        if (mHog == -1) // Not already set
        {
            Debug(QString("SetHogStatus: Setting 'hog' status on device %1")
                  .arg(mDeviceID));
            OSStatus err = AudioObjectSetPropertyData(mDeviceID, &pa, 0, nullptr,
                                                      sizeof(mHog), &mHog);
            if (err || mHog != getpid())
            {
                Warn(QString("SetHogStatus: Unable to set 'hog' status. Error = [%1]")
                     .arg(OSS_STATUS(err)));
                return false;
            }
            Debug(QString("SetHogStatus: Successfully set 'hog' status on device %1")
                  .arg(mDeviceID));
        }
    }
    else
    {
        if (mHog > -1) // Currently Set
        {
            Debug(QString("SetHogStatus: Releasing 'hog' status on device %1")
                  .arg(mDeviceID));
            pid_t hogPid = -1;
            OSStatus err = AudioObjectSetPropertyData(mDeviceID, &pa, 0, nullptr,
                                                      sizeof(hogPid), &hogPid);
            if (err || hogPid == getpid())
            {
                Warn(QString("SetHogStatus: Unable to release 'hog' status. Error = [%1]")
                     .arg(OSS_STATUS(err)));
                return false;
            }
            mHog = hogPid; // Reset internal state
        }
    }
    return true;
}

bool CoreAudioData::SetMixingSupport(bool mix)
{
    if (!mDeviceID)
        return false;
    int restore = -1;
    if (mMixerRestore == -1) // This is our first change to this setting. Store the original setting for restore
        restore = (GetMixingSupport() ? 1 : 0);
    UInt32 mixEnable = mix ? 1 : 0;
    Debug(QString("SetMixingSupport: %1abling mixing for device %2")
          .arg(mix ? "En" : "Dis")
          .arg(mDeviceID));

    AudioObjectPropertyAddress pa
    {
        kAudioDevicePropertySupportsMixing,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };
    OSStatus err = AudioObjectSetPropertyData(mDeviceID, &pa, 0, nullptr,
                                              sizeof(mixEnable), &mixEnable);
    if (err)
    {
        Warn(QString("SetMixingSupport: Unable to set MixingSupport to %1. Error = [%2]")
             .arg(mix ? "'On'" : "'Off'")
             .arg(OSS_STATUS(err)));
        return false;
    }
    if (mMixerRestore == -1)
        mMixerRestore = restore;
    return true;
}

bool CoreAudioData::GetMixingSupport()
{
    if (!mDeviceID)
        return false;
    UInt32 val = 0;
    UInt32 size = sizeof(val);
    AudioObjectPropertyAddress pa
    {
        kAudioDevicePropertySupportsMixing,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };
    OSStatus err = AudioObjectGetPropertyData(mDeviceID, &pa, 0, nullptr,
                                              &size, &val);
    if (err)
        return false;
    return (val > 0);
}

AudioStreamIDVec CoreAudioData::StreamsList(AudioDeviceID d)
{
    OSStatus       err;
    UInt32         listSize;
    AudioStreamIDVec vec {};

    AudioObjectPropertyAddress pa
    {
        kAudioDevicePropertyStreams,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    err = AudioObjectGetPropertyDataSize(d, &pa,
                                         0, nullptr, &listSize);
    if (err != noErr)
    {
        Error(QString("StreamsList: could not get list size: [%1]")
              .arg(OSS_STATUS(err)));
        return {};
    }

    try
    {
        vec.reserve(listSize / sizeof(AudioStreamID));
    }
    catch (...)
    {
        Error("StreamsList(): out of memory?");
        return {};
    }

    err = AudioObjectGetPropertyData(d, &pa,
                                     0, nullptr, &listSize, vec.data());
    if (err != noErr)
    {
        Error(QString("StreamsList: could not get list: [%1]")
              .arg(OSS_STATUS(err)));
        return {};
    }

    return vec;
}

AudioStreamRangedVec CoreAudioData::FormatsList(AudioStreamID s)
{
    OSStatus                     err;
    AudioStreamRangedVec         vec;
    UInt32                       listSize;

    AudioObjectPropertyAddress pa
    {
        kAudioStreamPropertyPhysicalFormats,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    // Retrieve all the stream formats supported by this output stream
    err = AudioObjectGetPropertyDataSize(s, &pa, 0, nullptr, &listSize);
    if (err != noErr)
    {
        Warn(QString("FormatsList(): couldn't get list size: [%1]")
             .arg(OSS_STATUS(err)));
        return {};
    }

    try
    {
        vec.reserve(listSize / sizeof(AudioStreamRangedDescription));
    }
    catch (...)
    {
        Error("FormatsList(): out of memory?");
        return {};
    }

    err = AudioObjectGetPropertyData(s, &pa, 0, nullptr, &listSize, vec.data());
    if (err != noErr)
    {
        Warn(QString("FormatsList: couldn't get list: [%1]")
             .arg(OSS_STATUS(err)));
        return {};
    }

    return vec;
}

static UInt32   sNumberCommonSampleRates = 15;
static Float64  sCommonSampleRates[] = {
    8000.0,   11025.0,  12000.0,
    16000.0,  22050.0,  24000.0,
    32000.0,  44100.0,  48000.0,
    64000.0,  88200.0,  96000.0,
    128000.0, 176400.0, 192000.0 };

static bool IsRateCommon(Float64 inRate)
{
    bool theAnswer = false;
    for(UInt32 i = 0; !theAnswer && (i < sNumberCommonSampleRates); i++)
    {
        theAnswer = inRate == sCommonSampleRates[i];
    }
    return theAnswer;
}

RatesVec CoreAudioData::RatesList(AudioDeviceID d)
{
    OSStatus                    err;
    AudioValueRangeVec          ranges;
    RatesVec                    finalvec;
    UInt32                      listSize;

    AudioObjectPropertyAddress pa
    {
        kAudioDevicePropertyAvailableNominalSampleRates,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    // retrieve size of rate list
    err = AudioObjectGetPropertyDataSize(d, &pa, 0, nullptr, &listSize);
    if (err != noErr)
    {
        Warn(QString("RatesList(): couldn't get data rate list size: [%1]")
             .arg(err));
        return {};
    }

    try
    {
        ranges.reserve(listSize / sizeof(AudioValueRange));
        finalvec.reserve(listSize / sizeof(AudioValueRange));
    }
    catch (...)
    {
        Error("RatesList(): out of memory?");
        return {};
    }

    err = AudioObjectGetPropertyData(d, &pa, 0, nullptr, &listSize, ranges.data());
    if (err != noErr)
    {
        Warn(QString("RatesList(): couldn't get list: [%1]")
             .arg(err));
        return {};
    }

    // iterate through the ranges and add the minimum, maximum, and common rates in between
    UInt32 theFirstIndex;
    UInt32 theLastIndex = 0;
    for(auto range : ranges)
    {
        theFirstIndex = theLastIndex;
        // find the index of the first common rate greater than or equal to the minimum
        while((theFirstIndex < sNumberCommonSampleRates) &&  (sCommonSampleRates[theFirstIndex] < range.mMinimum))
            theFirstIndex++;

        if (theFirstIndex >= sNumberCommonSampleRates)
            break;

        theLastIndex = theFirstIndex;
        // find the index of the first common rate greater than or equal to the maximum
        while((theLastIndex < sNumberCommonSampleRates) && (sCommonSampleRates[theLastIndex] < range.mMaximum))
        {
            finalvec.push_back(sCommonSampleRates[theLastIndex]);
            theLastIndex++;
        }
        if (IsRateCommon(range.mMinimum))
            finalvec.push_back(range.mMinimum);
        else if (IsRateCommon(range.mMaximum))
            finalvec.push_back(range.mMaximum);
    }

    return finalvec;
}

bool CoreAudioData::ChannelsList(AudioDeviceID /*d*/, bool passthru, ChannelsArr& chans)
{
    AudioStreamIDVec            streams;
    AudioStreamRangedVec        formats;
    bool                        founddigital = false;

    chans.fill(false);

    streams = StreamsList(mDeviceID);
    if (streams.empty())
        return false;

    if (passthru)
    {
        for (auto stream : streams)
        {
            formats = FormatsList(stream);
            if (formats.empty())
                continue;

            // Find a stream with a cac3 stream
            for (auto format : formats)
            {
                if (format.mFormat.mFormatID == 'IAC3' ||
                    format.mFormat.mFormatID == kAudioFormat60958AC3)
                {
                    chans[format.mFormat.mChannelsPerFrame] = true;
                    founddigital = true;
                }
            }
        }
    }

    if (!founddigital)
    {
        for (auto stream : streams)
        {
            formats = FormatsList(stream);
            if (formats.empty())
                continue;
            for (auto format : formats)
                if (format.mFormat.mChannelsPerFrame <= CHANNELS_MAX)
                    chans[format.mFormat.mChannelsPerFrame] = true;
        }
    }
    return true;
}

int CoreAudioData::OpenAnalog()
{
    AudioComponentDescription    desc;
    AudioStreamBasicDescription  DeviceFormat;
    AudioChannelLayout          *layout;
    AudioChannelLayout           new_layout;
    AudioDeviceID                defaultDevice = GetDefaultOutputDevice();
    AudioObjectPropertyAddress pa
    {
        kAudioHardwarePropertyDevices,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    Debug("OpenAnalog: Entering");

    desc.componentType = kAudioUnitType_Output;
    if (defaultDevice == mDeviceID)
    {
        desc.componentSubType = kAudioUnitSubType_DefaultOutput;
    }
    else
    {
        desc.componentSubType = kAudioUnitSubType_HALOutput;
    }
    desc.componentManufacturer = kAudioUnitManufacturer_Apple;
    desc.componentFlags = 0;
    desc.componentFlagsMask = 0;
    mDigitalInUse = false;

    AudioComponent comp = AudioComponentFindNext(nullptr, &desc);
    if (comp == nullptr)
    {
        Error("OpenAnalog: AudioComponentFindNext failed");
        return false;
    }

    OSErr err = AudioComponentInstanceNew(comp, &mOutputUnit);
    if (err)
    {
        Error(QString("OpenAnalog: AudioComponentInstanceNew returned %1")
              .arg(err));
        return false;
    }

    // Check if we have IO
    UInt32 hasIO      = 0;
    UInt32 size_hasIO = sizeof(hasIO);
    err = AudioUnitGetProperty(mOutputUnit,
                               kAudioOutputUnitProperty_HasIO,
                               kAudioUnitScope_Output,
                               0,
                               &hasIO, &size_hasIO);
    Debug(QString("OpenAnalog: HasIO (output) = %1").arg(hasIO));
    if (!hasIO)
    {
        UInt32 enableIO = 1;
        err = AudioUnitSetProperty(mOutputUnit,
                                   kAudioOutputUnitProperty_EnableIO,
                                   kAudioUnitScope_Global,
                                   0,
                                   &enableIO, sizeof(enableIO));
        if (err)
        {
            Warn(QString("OpenAnalog: failed enabling IO: %1")
                 .arg(err));
        }
        hasIO = 0;
        err = AudioUnitGetProperty(mOutputUnit,
                                   kAudioOutputUnitProperty_HasIO,
                                   kAudioUnitScope_Output,
                                   0,
                                   &hasIO, &size_hasIO);
        Debug(QString("HasIO = %1").arg(hasIO));
    }

    /*
     * We shouldn't have to do this distinction, however for some unknown reasons
     * assigning device to AudioUnit fail when switching from SPDIF mode
     */
    if (defaultDevice != mDeviceID)
    {
        err = AudioUnitSetProperty(mOutputUnit,
                                   kAudioOutputUnitProperty_CurrentDevice,
                                   kAudioUnitScope_Global,
                                   0,
                                   &mDeviceID, sizeof(mDeviceID));
        if (err)
        {
            Error(QString("OpenAnalog: Unable to set current device to %1. Error = %2")
                  .arg(mDeviceID)
                  .arg(err));
            return -1;
        }
    }
    /* Get the current format */
    UInt32 param_size = sizeof(AudioStreamBasicDescription);

    err = AudioUnitGetProperty(mOutputUnit,
                               kAudioUnitProperty_StreamFormat,
                               kAudioUnitScope_Input,
                               0,
                               &DeviceFormat,
                               &param_size );
    if (err)
    {
        Warn(QString("OpenAnalog: Unable to retrieve current stream format: [%1]")
              .arg(err));
    }
    else
    {
        Debug(QString("OpenAnalog: current format is: %1")
              .arg(StreamDescriptionToString(DeviceFormat)));
    }
    /* Get the channel layout of the device side of the unit */
    pa.mSelector = kAudioDevicePropertyPreferredChannelLayout;
    err = AudioObjectGetPropertyDataSize(kAudioObjectSystemObject, &pa,
                                         0, nullptr, &param_size);

    if(!err)
    {
        layout = (AudioChannelLayout *) malloc(param_size);

        err = AudioObjectGetPropertyData(kAudioObjectSystemObject, &pa,
                                         0, nullptr, &param_size, layout);

        /* We need to "fill out" the ChannelLayout, because there are multiple ways that it can be set */
        if(layout->mChannelLayoutTag == kAudioChannelLayoutTag_UseChannelBitmap)
        {
            /* bitmap defined channellayout */
            err = AudioFormatGetProperty(kAudioFormatProperty_ChannelLayoutForBitmap,
                                         sizeof(UInt32), &layout->mChannelBitmap,
                                         &param_size,
                                         layout);
            if (err)
                Warn("OpenAnalog: Can't retrieve current channel layout");
        }
        else if(layout->mChannelLayoutTag != kAudioChannelLayoutTag_UseChannelDescriptions )
        {
            /* layouttags defined channellayout */
            err = AudioFormatGetProperty(kAudioFormatProperty_ChannelLayoutForTag,
                                         sizeof(AudioChannelLayoutTag),
                                         &layout->mChannelLayoutTag,
                                         &param_size,
                                         layout);
            if (err)
                Warn("OpenAnalog: Can't retrieve current channel layout");
        }

        Debug(QString("OpenAnalog: Layout of AUHAL has %1 channels")
              .arg(layout->mNumberChannelDescriptions));

        int channels_found = 0;
        for(UInt32 i = 0; i < layout->mNumberChannelDescriptions; i++)
        {
            Debug(QString("OpenAnalog: this is channel: %1")
                  .arg(layout->mChannelDescriptions[i].mChannelLabel));

            switch( layout->mChannelDescriptions[i].mChannelLabel)
            {
                case kAudioChannelLabel_Left:
                case kAudioChannelLabel_Right:
                case kAudioChannelLabel_Center:
                case kAudioChannelLabel_LFEScreen:
                case kAudioChannelLabel_LeftSurround:
                case kAudioChannelLabel_RightSurround:
                case kAudioChannelLabel_RearSurroundLeft:
                case kAudioChannelLabel_RearSurroundRight:
                case kAudioChannelLabel_CenterSurround:
                    channels_found++;
                    break;
                default:
                    Debug(QString("unrecognized channel form provided by driver: %1")
                          .arg(layout->mChannelDescriptions[i].mChannelLabel));
            }
        }
        if(channels_found == 0)
        {
            Warn("Audio device is not configured. "
                 "You should configure your speaker layout with "
                 "the \"Audio Midi Setup\" utility in /Applications/"
                 "Utilities.");
        }
        free(layout);
    }
    else
    {
        Warn("this driver does not support kAudioDevicePropertyPreferredChannelLayout.");
    }

    memset (&new_layout, 0, sizeof(new_layout));
    switch(mCA->m_channels)
    {
        case 1:
            new_layout.mChannelLayoutTag = kAudioChannelLayoutTag_Mono;
            break;
        case 2:
            new_layout.mChannelLayoutTag = kAudioChannelLayoutTag_Stereo;
            break;
        case 6:
            //  3F2-LFE        L   R   C    LFE  LS   RS
            new_layout.mChannelLayoutTag = kAudioChannelLayoutTag_AudioUnit_5_1;
            break;
        case 8:
            // We need
            // 3F4-LFE        L   R   C    LFE  Rls  Rrs  LS   RS
            // but doesn't exist, so we'll swap channels later
            new_layout.mChannelLayoutTag = kAudioChannelLayoutTag_MPEG_7_1_A; // L R C LFE Ls Rs Lc Rc
            break;
    }
    /* Set new_layout as the layout */
    err = AudioUnitSetProperty(mOutputUnit,
                               kAudioUnitProperty_AudioChannelLayout,
                               kAudioUnitScope_Input,
                               0,
                               &new_layout, sizeof(new_layout));
    if (err)
    {
        Warn(QString("OpenAnalog: couldn't set channels layout [%1]")
             .arg(err));
    }

    if(new_layout.mNumberChannelDescriptions > 0)
        free(new_layout.mChannelDescriptions);

    // Set up the audio output unit
    int formatFlags;
    switch (mCA->m_outputFormat)
    {
        case FORMAT_S16:
            formatFlags = kLinearPCMFormatFlagIsSignedInteger;
            break;
        case FORMAT_FLT:
            formatFlags = kLinearPCMFormatFlagIsFloat;
            break;
        default:
            formatFlags = kLinearPCMFormatFlagIsSignedInteger;
            break;
    }

    AudioStreamBasicDescription conv_in_desc;
    memset(&conv_in_desc, 0, sizeof(AudioStreamBasicDescription));
    conv_in_desc.mSampleRate       = mCA->m_sampleRate;
    conv_in_desc.mFormatID         = kAudioFormatLinearPCM;
    conv_in_desc.mFormatFlags      = formatFlags |
        kAudioFormatFlagsNativeEndian |
        kLinearPCMFormatFlagIsPacked;
    conv_in_desc.mBytesPerPacket   = mCA->m_outputBytesPerFrame;
    // This seems inefficient, does it hurt if we increase this?
    conv_in_desc.mFramesPerPacket  = 1;
    conv_in_desc.mBytesPerFrame    = mCA->m_outputBytesPerFrame;
    conv_in_desc.mChannelsPerFrame = mCA->m_channels;
    conv_in_desc.mBitsPerChannel   =
        AudioOutputSettings::FormatToBits(mCA->m_outputFormat);

    /* Set AudioUnit input format */
    err = AudioUnitSetProperty(mOutputUnit,
                               kAudioUnitProperty_StreamFormat,
                               kAudioUnitScope_Input,
                               0,
                               &conv_in_desc,
                               sizeof(AudioStreamBasicDescription));
    if (err)
    {
        Error(QString("OpenAnalog: AudioUnitSetProperty returned [%1]")
              .arg(err));
        return false;
    }
    Debug(QString("OpenAnalog: set format as %1")
          .arg(StreamDescriptionToString(conv_in_desc)));
    /* Retrieve actual format */
    err = AudioUnitGetProperty(mOutputUnit,
                               kAudioUnitProperty_StreamFormat,
                               kAudioUnitScope_Input,
                               0,
                               &DeviceFormat,
                               &param_size);

    Debug(QString("OpenAnalog: the actual set AU format is %1")
          .arg(StreamDescriptionToString(DeviceFormat)));

    // Attach callback to default output
    AURenderCallbackStruct input;
    input.inputProc = RenderCallbackAnalog;
    input.inputProcRefCon = this;

    err = AudioUnitSetProperty(mOutputUnit,
                               kAudioUnitProperty_SetRenderCallback,
                               kAudioUnitScope_Input,
                               0, &input, sizeof(input));
    if (err)
    {
        Error(QString("OpenAnalog: AudioUnitSetProperty (callback) returned [%1]")
              .arg(err));
        return false;
    }
    mIoProc = true;

    // We're all set up - start the audio output unit
    ComponentResult res = AudioUnitInitialize(mOutputUnit);
    if (res)
    {
        Error(QString("OpenAnalog: AudioUnitInitialize error: [%1]")
              .arg(res));
        return false;
    }
    mInitialized = true;

    err = AudioOutputUnitStart(mOutputUnit);
    if (err)
    {
        Error(QString("OpenAnalog: AudioOutputUnitStart error: [%1]")
              .arg(err));
        return false;
    }
    mStarted = true;
    return true;
}

void CoreAudioData::CloseAnalog()
{
    OSStatus err;

    Debug(QString("CloseAnalog: Entering: %1")
          .arg((long)mOutputUnit));
    if (mOutputUnit)
    {
        if (mStarted)
        {
            err = AudioOutputUnitStop(mOutputUnit);
            Debug(QString("CloseAnalog: AudioOutputUnitStop %1")
                  .arg(err));
        }
        if (mInitialized)
        {
            err = AudioUnitUninitialize(mOutputUnit);
            Debug(QString("CloseAnalog: AudioUnitUninitialize %1")
                  .arg(err));
        }
        err = AudioComponentInstanceDispose(mOutputUnit);
        Debug(QString("CloseAnalog: CloseComponent %1")
              .arg(err));
        mOutputUnit = nullptr;
    }
    mIoProc = false;
    mInitialized = false;
    mStarted = false;
    mWasDigital = false;
}

bool CoreAudioData::OpenSPDIF()
{
    OSStatus       err;
    AudioStreamIDVec streams;
    AudioStreamBasicDescription outputFormat {};

    Debug("OpenSPDIF: Entering");

    streams = StreamsList(mDeviceID);
    if (streams.empty())
    {
        Warn("OpenSPDIF: Couldn't retrieve list of streams");
        return false;
    }

    for (size_t i = 0; i < streams.size(); ++i)
    {
        AudioStreamRangedVec formats = FormatsList(streams[i]);
        if (formats.empty())
            continue;

        // Find a stream with a cac3 stream
        for (auto format : formats)
        {
            Debug(QString("OpenSPDIF: Considering Physical Format: %1")
                  .arg(StreamDescriptionToString(format.mFormat)));
            if ((format.mFormat.mFormatID == 'IAC3' ||
                 format.mFormat.mFormatID == kAudioFormat60958AC3) &&
                format.mFormat.mSampleRate == mCA->m_sampleRate)
            {
                Debug("OpenSPDIF: Found digital format");
                mStreamIndex  = i;
                mStreamID     = streams[i];
                outputFormat  = format.mFormat;
                break;
            }
        }
        if (outputFormat.mFormatID)
            break;
    }

    if (!outputFormat.mFormatID)
    {
        Error(QString("OpenSPDIF: Couldn't find suitable output"));
        return false;
    }

    if (!mRevertFormat)
    {
        AudioObjectPropertyAddress pa
        {
            kAudioStreamPropertyPhysicalFormat,
            kAudioObjectPropertyScopeGlobal,
            kAudioObjectPropertyElementMaster
        };

        // Retrieve the original format of this stream first
        // if not done so already
        UInt32 paramSize = sizeof(mFormatOrig);
        err = AudioObjectGetPropertyData(mStreamID, &pa, 0, nullptr,
                                         &paramSize, &mFormatOrig);
        if (err != noErr)
        {
            Warn(QString("OpenSPDIF - could not retrieve the original streamformat: [%1]")
                 .arg(OSS_STATUS(err)));
        }
        else
        {
            mRevertFormat = true;
        }
    }

    mDigitalInUse = true;

    SetAutoHogMode(false);
    bool autoHog = GetAutoHogMode();
    if (!autoHog)
    {
        // Hog the device
        SetHogStatus(true);
        // Set mixable to false if we are allowed to
        SetMixingSupport(false);
    }

    mFormatNew = outputFormat;
    if (!AudioStreamChangeFormat(mStreamID, mFormatNew))
    {
        return false;
    }
    mBytesPerPacket = mFormatNew.mBytesPerPacket;

    // Add IOProc callback
    err = AudioDeviceCreateIOProcID(mDeviceID,
                                    (AudioDeviceIOProc)RenderCallbackSPDIF,
                                    (void *)this, &mIoProcID);
    if (err != noErr)
    {
        Error(QString("OpenSPDIF: AudioDeviceCreateIOProcID failed: [%1]")
              .arg(OSS_STATUS(err)));
        return false;
    }
    mIoProc = true;

    // Start device
    err = AudioDeviceStart(mDeviceID, mIoProcID);
    if (err != noErr)
    {
        Error(QString("OpenSPDIF: AudioDeviceStart failed: [%1]")
              .arg(OSS_STATUS(err)));
        return false;
    }
    mStarted = true;
    return true;
}

void CoreAudioData::CloseSPDIF()
{
    OSStatus  err;

    Debug(QString("CloseSPDIF: Entering [%1]").arg(mDigitalInUse));;
    if (!mDigitalInUse)
        return;

    // Stop device
    if (mStarted)
    {
        err = AudioDeviceStop(mDeviceID, mIoProcID);
        if (err != noErr)
            Error(QString("CloseSPDIF: AudioDeviceStop failed: [%1]")
                  .arg(OSS_STATUS(err)));
        mStarted = false;
    }

    // Remove IOProc callback
    if (mIoProc)
    {
        err = AudioDeviceDestroyIOProcID(mDeviceID, mIoProcID);
        if (err != noErr)
            Error(QString("CloseSPDIF: AudioDeviceDestroyIOProcID failed: [%1]")
                  .arg(OSS_STATUS(err)));
        mIoProc = false;
    }

    if (mRevertFormat)
    {
        AudioStreamChangeFormat(mStreamID, mFormatOrig);
        mRevertFormat = false;
    }

    SetHogStatus(false);
    if (mMixerRestore > -1) // We changed the mixer status
        SetMixingSupport((mMixerRestore != 0));
    AudioHardwareUnload();
    mMixerRestore = -1;
    mBytesPerPacket = -1;
    mStreamIndex = -1;
    mWasDigital = true;
}

int CoreAudioData::AudioStreamChangeFormat(AudioStreamID               s,
                                           AudioStreamBasicDescription format)
{
    Debug(QString("AudioStreamChangeFormat: %1 -> %2")
          .arg(s)
          .arg(StreamDescriptionToString(format)));

    AudioObjectPropertyAddress pa
    {
        kAudioStreamPropertyPhysicalFormat,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };
    OSStatus err = AudioObjectSetPropertyData(s, &pa, 0, nullptr,
                                              sizeof(format), &format);
    if (err != noErr)
    {
        Error(QString("AudioStreamChangeFormat couldn't set stream format: [%1]")
              .arg(OSS_STATUS(err)));
        return false;
    }
    return true;
}

bool CoreAudioData::FindAC3Stream()
{
    AudioStreamIDVec streams;


    // Get a list of all the streams on this device
    streams = StreamsList(mDeviceID);
    if (streams.empty())
        return false;

    for (auto stream : streams)
    {
        AudioStreamRangedVec formats = FormatsList(stream);
        if (formats.empty())
            continue;

        // Find a stream with a cac3 stream
        for (auto format : formats) {
            if (format.mFormat.mFormatID == 'IAC3' ||
                format.mFormat.mFormatID == kAudioFormat60958AC3)
            {
                Debug("FindAC3Stream: found digital format");
                return true;
            }
        }
    }

    return false;
}

void CoreAudioData::ResetAudioDevices()
{
    UInt32         size;
    AudioObjectPropertyAddress pa
    {
        kAudioHardwarePropertyDevices,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    OSStatus err = AudioObjectGetPropertyDataSize(kAudioObjectSystemObject, &pa,
                                                  0, nullptr, &size);
    if (err)
    {
        Warn(QString("GetPropertyDataSize: Unable to retrieve the property sizes. "
                     "Error [%1]")
             .arg(err));
        return;
    }

    std::vector<AudioDeviceID> devices = {};
    devices.resize(size / sizeof(AudioDeviceID));
    err = AudioObjectGetPropertyData(kAudioObjectSystemObject, &pa,
                                     0, nullptr, &size, devices.data());
    if (err)
    {
        Warn(QString("GetPropertyData: Unable to retrieve the list of available devices. "
                     "Error [%1]")
             .arg(err));
        return;
    }

    for (const auto & dev : devices)
    {
        AudioStreamIDVec streams;

        streams = StreamsList(dev);
        if (streams.empty())
            continue;
        for (auto stream : streams)
            ResetStream(stream);
    }
}

void CoreAudioData::ResetStream(AudioStreamID s)
{
    AudioStreamBasicDescription  currentFormat;
    OSStatus                     err;
    UInt32                       paramSize;
    AudioObjectPropertyAddress pa
    {
        kAudioStreamPropertyPhysicalFormat,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };


    // Find the streams current physical format
    paramSize = sizeof(currentFormat);
    AudioObjectGetPropertyData(s, &pa, 0, nullptr,
                               &paramSize, &currentFormat);

    // If it's currently AC-3/SPDIF then reset it to some mixable format
    if (currentFormat.mFormatID == 'IAC3' ||
        currentFormat.mFormatID == kAudioFormat60958AC3)
    {
        AudioStreamRangedVec        formats    = FormatsList(s);
        bool                        streamReset = false;


        if (formats.empty())
            return;

        for (auto format : formats) {
            if (format.mFormat.mFormatID == kAudioFormatLinearPCM)
            {
              err = AudioObjectSetPropertyData(s, &pa, 0, nullptr,
                                               sizeof(format), &(format.mFormat));
                if (err != noErr)
                {
                    Warn(QString("ResetStream: could not set physical format: [%1]")
                         .arg(OSS_STATUS(err)));
                    continue;
                }
                
                streamReset = true;
                sleep(1);   // For the change to take effect
            }
        }
    }
}

QMap<QString, QString> *AudioOutputCA::GetDevices(const char */*type*/)
{
    auto *devs = new QMap<QString, QString>();

    // Obtain a list of all available audio devices
    UInt32 size = 0;

    AudioObjectPropertyAddress pa
    {
        kAudioHardwarePropertyDevices,
        kAudioObjectPropertyScopeGlobal,
        kAudioObjectPropertyElementMaster
    };

    OSStatus err = AudioObjectGetPropertyDataSize(kAudioObjectSystemObject, &pa,
                                                  0, nullptr, &size);
    if (err)
    {
        VBAUDIO(QString("GetPropertyDataSize: Unable to retrieve the property sizes. "
                     "Error [%1]")
             .arg(err));
        return devs;
    }

    UInt32 deviceCount = size / sizeof(AudioDeviceID);
    auto* pDevices = new AudioDeviceID[deviceCount];
    err = AudioObjectGetPropertyData(kAudioObjectSystemObject, &pa,
                                     0, nullptr, &size, pDevices);
    if (err)
    {
        VBAUDIO(QString("AudioOutputCA::GetDevices: Unable to retrieve the list of "
                        "available devices. Error [%1]")
                .arg(err));
    }
    else
    {
        VBAUDIO(QString("GetDevices: Number of devices: %1").arg(deviceCount));

        for (UInt32 dev = 0; dev < deviceCount; dev++)
        {
            CoreAudioData device(nullptr, pDevices[dev]);
            if (device.GetTotalOutputChannels() == 0)
                continue;
            QString *name = device.GetName();
            if (name)
            {
                devs->insert(*name, QString());
                delete name;
            }
        }
    }
    return devs;
}