pa_unix.c

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    /* Allocate native buffers. */
    pahsc->pahsc_BytesPerInputBuffer = past->past_FramesPerUserBuffer *
                                       past->past_NumInputChannels * sizeof(short);
    if( past->past_NumInputChannels > 0)
    {
        pahsc->pahsc_NativeInputBuffer = (short *) malloc(pahsc->pahsc_BytesPerInputBuffer);
        if( pahsc->pahsc_NativeInputBuffer == NULL )
        {
            result = paInsufficientMemory;
            goto error;
        }
    }
    pahsc->pahsc_BytesPerOutputBuffer = past->past_FramesPerUserBuffer *
                                        past->past_NumOutputChannels * sizeof(short);
    if( past->past_NumOutputChannels > 0)
    {
        pahsc->pahsc_NativeOutputBuffer = (short *) malloc(pahsc->pahsc_BytesPerOutputBuffer);
        if( pahsc->pahsc_NativeOutputBuffer == NULL )
        {
            result = paInsufficientMemory;
            goto error;
        }
    }

    /* DBUG(("PaHost_OpenStream: pahsc_MinFramesPerHostBuffer = %d\n", pahsc->pahsc_MinFramesPerHostBuffer )); */
    minNumBuffers = Pa_GetMinNumBuffers( past->past_FramesPerUserBuffer, past->past_SampleRate );
    past->past_NumUserBuffers = ( minNumBuffers > past->past_NumUserBuffers ) ? minNumBuffers : past->past_NumUserBuffers;

    pahsc->pahsc_InverseMicrosPerBuffer = past->past_SampleRate / (1000000.0 * past->past_FramesPerUserBuffer);
    DBUG(("past_SampleRate = %g\n", past->past_SampleRate ));
    DBUG(("past_FramesPerUserBuffer = %d\n", past->past_FramesPerUserBuffer ));
    DBUG(("pahsc_InverseMicrosPerBuffer = %g\n", pahsc->pahsc_InverseMicrosPerBuffer ));

    /* ------------------------- OPEN DEVICE -----------------------*/

    /* just output */
    if (past->past_OutputDeviceID == past->past_InputDeviceID)
    {

        if ((past->past_NumOutputChannels > 0) && (past->past_NumInputChannels > 0) )
        {
            pad = Pa_GetInternalDevice( past->past_OutputDeviceID );
            DBUG(("PaHost_OpenStream: attempt to open %s for O_RDWR\n", pad->pad_DeviceName ));

            /* dmazzoni: test it first in nonblocking mode to
               make sure the device is not busy */
            pahsc->pahsc_InputHandle = open(pad->pad_DeviceName,O_RDWR|O_NONBLOCK);
            if(pahsc->pahsc_InputHandle==-1)
            {
                ERR_RPT(("PaHost_OpenStream: could not open %s for O_RDWR\n", pad->pad_DeviceName ));
                result = paHostError;
                goto error;
            }
            close(pahsc->pahsc_InputHandle);

            pahsc->pahsc_OutputHandle = pahsc->pahsc_InputHandle =
                                            open(pad->pad_DeviceName,O_RDWR);
            if(pahsc->pahsc_InputHandle==-1)
            {
                ERR_RPT(("PaHost_OpenStream: could not open %s for O_RDWR\n", pad->pad_DeviceName ));
                result = paHostError;
                goto error;
            }
            Pa_SetLatency( pahsc->pahsc_OutputHandle,
                           past->past_NumUserBuffers, past->past_FramesPerUserBuffer,
                           past->past_NumOutputChannels );
            result = Pa_SetupDeviceFormat( pahsc->pahsc_OutputHandle,
                                           past->past_NumOutputChannels, (int)past->past_SampleRate );
        }
    }
    else
    {
        if (past->past_NumOutputChannels > 0)
        {
            pad = Pa_GetInternalDevice( past->past_OutputDeviceID );
            DBUG(("PaHost_OpenStream: attempt to open %s for O_WRONLY\n", pad->pad_DeviceName ));
            /* dmazzoni: test it first in nonblocking mode to
               make sure the device is not busy */
            pahsc->pahsc_OutputHandle = open(pad->pad_DeviceName,O_WRONLY|O_NONBLOCK);
            if(pahsc->pahsc_OutputHandle==-1)
            {
                ERR_RPT(("PaHost_OpenStream: could not open %s for O_WRONLY\n", pad->pad_DeviceName ));
                result = paHostError;
                goto error;
            }
            close(pahsc->pahsc_OutputHandle);

            pahsc->pahsc_OutputHandle = open(pad->pad_DeviceName,O_WRONLY);
            if(pahsc->pahsc_OutputHandle==-1)
            {
                ERR_RPT(("PaHost_OpenStream: could not open %s for O_WRONLY\n", pad->pad_DeviceName ));
                result = paHostError;
                goto error;
            }
            Pa_SetLatency( pahsc->pahsc_OutputHandle,
                           past->past_NumUserBuffers, past->past_FramesPerUserBuffer,
                           past->past_NumOutputChannels );
            result = Pa_SetupOutputDeviceFormat( pahsc->pahsc_OutputHandle,
                                           past->past_NumOutputChannels, (int)past->past_SampleRate );
        }

        if (past->past_NumInputChannels > 0)
        {
            pad = Pa_GetInternalDevice( past->past_InputDeviceID );
            DBUG(("PaHost_OpenStream: attempt to open %s for O_RDONLY\n", pad->pad_DeviceName ));
            /* dmazzoni: test it first in nonblocking mode to
               make sure the device is not busy */
            pahsc->pahsc_InputHandle = open(pad->pad_DeviceName,O_RDONLY|O_NONBLOCK);
            if(pahsc->pahsc_InputHandle==-1)
            {
                ERR_RPT(("PaHost_OpenStream: could not open %s for O_RDONLY\n", pad->pad_DeviceName ));
                result = paHostError;
                goto error;
            }
            close(pahsc->pahsc_InputHandle);

            pahsc->pahsc_InputHandle = open(pad->pad_DeviceName,O_RDONLY);
            if(pahsc->pahsc_InputHandle==-1)
            {
                ERR_RPT(("PaHost_OpenStream: could not open %s for O_RDONLY\n", pad->pad_DeviceName ));
                result = paHostError;
                goto error;
            }
            Pa_SetLatency( pahsc->pahsc_InputHandle, /* DH20010115 - was OutputHandle! */
                           past->past_NumUserBuffers, past->past_FramesPerUserBuffer,
                           past->past_NumInputChannels );
            result = Pa_SetupInputDeviceFormat( pahsc->pahsc_InputHandle,
                                           past->past_NumInputChannels, (int)past->past_SampleRate );
        }
    }


    DBUG(("PaHost_OpenStream: SUCCESS - result = %d\n", result ));
    return result;

error:
    ERR_RPT(("PaHost_OpenStream: ERROR - result = %d\n", result ));
    PaHost_CloseStream( past );
    return result;
}

/*************************************************************************/
PaError PaHost_StartOutput( internalPortAudioStream *past )
{
    return paNoError;
}

/*************************************************************************/
PaError PaHost_StartInput( internalPortAudioStream *past )
{
    return paNoError;
}

/*************************************************************************/
PaError PaHost_StartEngine( internalPortAudioStream *past )
{
    PaHostSoundControl *pahsc;
    PaError             result = paNoError;
    int                 hres;

    pahsc = (PaHostSoundControl *) past->past_DeviceData;

    past->past_StopSoon = 0;
    past->past_StopNow = 0;
    past->past_IsActive = 1;

    /* Use pthread_create() instead of __clone() because:
     *   - pthread_create also works for other UNIX systems like Solaris,
     *   - the Java HotSpot VM crashes in pthread_setcanceltype() when using __clone()
     */
    hres = pthread_create(&(pahsc->pahsc_AudioThread),
                          NULL /*pthread_attr_t * attr*/,
                          (pthread_function_t)Pa_AudioThreadProc, past);
    if( hres != 0 )
    {
        result = paHostError;
        sPaHostError = hres;
        pahsc->pahsc_IsAudioThreadValid = 0;
        goto error;
    }
    pahsc->pahsc_IsAudioThreadValid = 1;

error:
    return result;
}

/*************************************************************************/
PaError PaHost_StopEngine( internalPortAudioStream *past, int abort )
{
    int                 hres;
    PaError             result = paNoError;
    PaHostSoundControl *pahsc = (PaHostSoundControl *) past->past_DeviceData;

    if( pahsc == NULL ) return paNoError;

    /* Tell background thread to stop generating more data and to let current data play out. */
    past->past_StopSoon = 1;
    /* If aborting, tell background thread to stop NOW! */
    if( abort ) past->past_StopNow = 1;

    /* Join thread to recover memory resources. */
    if( pahsc->pahsc_IsAudioThreadValid )
    {
        /* This check is needed for GNUSTEP - SB20010904 */
        if ( !pthread_equal( pahsc->pahsc_AudioThread, pthread_self() ) )
        {
            hres = pthread_join( pahsc->pahsc_AudioThread, NULL );
        }
        else
        {
            DBUG(("Play thread was stopped from itself - can't do pthread_join()\n"));
            hres = 0;
        }

        if( hres != 0 )
        {
            result = paHostError;
            sPaHostError = hres;
        }
        pahsc->pahsc_IsAudioThreadValid = 0;
    }

    past->past_IsActive = 0;

    return result;
}

/*************************************************************************/
PaError PaHost_StopInput( internalPortAudioStream *past, int abort )
{
    return paNoError;
}

/*************************************************************************/
PaError PaHost_StopOutput( internalPortAudioStream *past, int abort )
{
    return paNoError;
}

/*******************************************************************/
PaError PaHost_CloseStream( internalPortAudioStream   *past )
{
    PaHostSoundControl *pahsc;

    if( past == NULL ) return paBadStreamPtr;
    pahsc = (PaHostSoundControl *) past->past_DeviceData;
    if( pahsc == NULL ) return paNoError;

    if( pahsc->pahsc_OutputHandle != BAD_DEVICE_ID )
    {
        int err = 0;
        DBUG(("PaHost_CloseStream: attempt to close output device handle = %d\n",
              pahsc->pahsc_OutputHandle ));

        Pa_FlushStream(pahsc->pahsc_OutputHandle);

        err = close(pahsc->pahsc_OutputHandle);
        if( err < 0 )
        {
            ERR_RPT(("PaHost_CloseStream: warning, closing output device failed.\n"));
        }
    }

    if( (pahsc->pahsc_InputHandle != BAD_DEVICE_ID) &&
            (pahsc->pahsc_InputHandle != pahsc->pahsc_OutputHandle) )
    {
        int err = 0;
        DBUG(("PaHost_CloseStream: attempt to close input device handle = %d\n",
              pahsc->pahsc_InputHandle ));

        Pa_FlushStream(pahsc->pahsc_InputHandle);

        err = close(pahsc->pahsc_InputHandle);
        if( err < 0 )
        {
            ERR_RPT(("PaHost_CloseStream: warning, closing input device failed.\n"));
        }
    }
    pahsc->pahsc_OutputHandle = BAD_DEVICE_ID;
    pahsc->pahsc_InputHandle = BAD_DEVICE_ID;

    if( pahsc->pahsc_NativeInputBuffer )
    {
        free( pahsc->pahsc_NativeInputBuffer );
        pahsc->pahsc_NativeInputBuffer = NULL;
    }
    if( pahsc->pahsc_NativeOutputBuffer )
    {
        free( pahsc->pahsc_NativeOutputBuffer );
        pahsc->pahsc_NativeOutputBuffer = NULL;
    }

    free( pahsc );
    past->past_DeviceData = NULL;
    return paNoError;
}

/*************************************************************************/
PaError PaHost_Term( void )
{
    /* Free all of the linked devices. */
    internalPortAudioDevice *pad, *nextPad;
    pad = sDeviceList;
    while( pad != NULL )
    {
        nextPad = pad->pad_Next;
        DBUG(("PaHost_Term: freeing %s\n", pad->pad_DeviceName ));
        PaHost_FreeFastMemory( pad, sizeof(internalPortAudioDevice) );
        pad = nextPad;
    }
    sDeviceList = NULL;
    return 0;
}

/*************************************************************************
 * Sleep for the requested number of milliseconds.
 */
void Pa_Sleep( long msec )
{
#if 0
    struct timeval timeout;
    timeout.tv_sec = msec / 1000;
    timeout.tv_usec = (msec % 1000) * 1000;
    select( 0, NULL, NULL, NULL, &timeout );
#else
    long usecs = msec * 1000;
    usleep( usecs );
#endif
}

/*************************************************************************
 * Allocate memory that can be accessed in real-time.
 * This may need to be held in physical memory so that it is not
 * paged to virtual memory.
 * This call MUST be balanced with a call to PaHost_FreeFastMemory().
 */
void *PaHost_AllocateFastMemory( long numBytes )
{
    void *addr = malloc( numBytes ); /* FIXME - do we need physical, wired, non-virtual memory? */
    if( addr != NULL ) memset( addr, 0, numBytes );
    return addr;
}

/*************************************************************************
 * Free memory that could be accessed in real-time.
 * This call MUST be balanced with a call to PaHost_AllocateFastMemory().
 */
void PaHost_FreeFastMemory( void *addr, long numBytes )
{
    if( addr != NULL ) free( addr );
}


/***********************************************************************/
PaError PaHost_StreamActive( internalPortAudioStream   *past )
{
    PaHostSoundControl *pahsc;
    if( past == NULL ) return paBadStreamPtr;
    pahsc = (PaHostSoundControl *) past->past_DeviceData;
    if( pahsc == NULL ) return paInternalError;
    return (PaError) (past->past_IsActive != 0);
}

/***********************************************************************/
long Pa_GetHostError( void )
{
    return (long) sPaHostError;
}