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PortAudio
2.0
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#include <pa_hostapi.h>
Data Fields | |
| PaUtilPrivatePaFrontHostApiInfo | privatePaFrontInfo |
| PaHostApiInfo | info |
| PaDeviceInfo ** | deviceInfos |
| void(* | Terminate )(struct PaUtilHostApiRepresentation *hostApi) |
| PaError(* | OpenStream )(struct PaUtilHostApiRepresentation *hostApi, PaStream **stream, const PaStreamParameters *inputParameters, const PaStreamParameters *outputParameters, double sampleRate, unsigned long framesPerCallback, PaStreamFlags streamFlags, PaStreamCallback *streamCallback, void *userData) |
| PaError(* | IsFormatSupported )(struct PaUtilHostApiRepresentation *hostApi, const PaStreamParameters *inputParameters, const PaStreamParameters *outputParameters, double sampleRate) |
A structure representing the interface to a host API. Contains both concrete data and pointers to functions which implement the interface.
| PaDeviceInfo** PaUtilHostApiRepresentation::deviceInfos |
| PaHostApiInfo PaUtilHostApiRepresentation::info |
The host api implementation should populate the info field. In the case of info.defaultInputDevice and info.defaultOutputDevice the values stored should be 0 based indices within the host api's own device index range (0 to deviceCount). These values will be converted to global device indices by pa_front after PaUtilHostApiInitializer() returns.
Referenced by PaAsio_Initialize(), PaAudioIO_Initialize(), PaJack_Initialize(), PaMacCore_Initialize(), PaOSS_Initialize(), PaPulseAudio_Initialize(), PaPulseAudio_StartStreamCb(), PaSkeleton_Initialize(), PaSndio_Initialize(), PaUtil_DeviceIndexToHostApiDeviceIndex(), PaWasapi_Initialize(), PaWinDs_Initialize(), PaWinMme_Initialize(), and PaWinWdm_Initialize().
| PaError(* PaUtilHostApiRepresentation::IsFormatSupported)(struct PaUtilHostApiRepresentation *hostApi, const PaStreamParameters *inputParameters, const PaStreamParameters *outputParameters, double sampleRate) |
Referenced by Pa_IsFormatSupported(), PaAudioIO_Initialize(), PaMacCore_Initialize(), and PaSkeleton_Initialize().
| PaError(* PaUtilHostApiRepresentation::OpenStream)(struct PaUtilHostApiRepresentation *hostApi, PaStream **stream, const PaStreamParameters *inputParameters, const PaStreamParameters *outputParameters, double sampleRate, unsigned long framesPerCallback, PaStreamFlags streamFlags, PaStreamCallback *streamCallback, void *userData) |
The inputParameters and outputParameters pointers should not be saved as they will not remain valid after OpenStream is called.
The following guarantees are made about parameters to (*OpenStream)():
[NOTE: the following list up to *END PA FRONT VALIDATIONS* should be
kept in sync with the one for ValidateOpenStreamParameters and
Pa_OpenStream in pa_front.c]
PaHostApiRepresentation *hostApi
- is valid for this implementation
PaStream** stream
- is non-null
- at least one of inputParameters & outputParmeters is valid (not NULL)
- if inputParameters & outputParmeters are both valid, that
inputParameters->device & outputParmeters->device both use the same host api
PaDeviceIndex inputParameters->device
- is within range (0 to Pa_CountDevices-1) Or:
- is paUseHostApiSpecificDeviceSpecification and
inputParameters->hostApiSpecificStreamInfo is non-NULL and refers
to a valid host api
int inputParameters->numChannels
- if inputParameters->device is not paUseHostApiSpecificDeviceSpecification, numInputChannels is > 0
- upper bound is NOT validated against device capabilities
PaSampleFormat inputParameters->sampleFormat
- is one of the sample formats defined in portaudio.h
void *inputParameters->hostApiSpecificStreamInfo
- if supplied its hostApi field matches the input device's host Api
PaDeviceIndex outputParmeters->device
- is within range (0 to Pa_CountDevices-1)
int outputParmeters->numChannels
- if inputDevice is valid, numInputChannels is > 0
- upper bound is NOT validated against device capabilities
PaSampleFormat outputParmeters->sampleFormat
- is one of the sample formats defined in portaudio.h
void *outputParmeters->hostApiSpecificStreamInfo
- if supplied its hostApi field matches the output device's host Api
double sampleRate
- is not an 'absurd' rate (less than 1000. or greater than 384000.)
- sampleRate is NOT validated against device capabilities
PaStreamFlags streamFlags
- unused platform neutral flags are zero
- paNeverDropInput is only used for full-duplex callback streams
with variable buffer size (paFramesPerBufferUnspecified)
[*END PA FRONT VALIDATIONS*]
The following validations MUST be performed by (*OpenStream)():
- check that input device can support numInputChannels
- check that input device can support inputSampleFormat, or that
we have the capability to convert from outputSampleFormat to
a native format
- if inputStreamInfo is supplied, validate its contents,
or return an error if no inputStreamInfo is expected
- check that output device can support numOutputChannels
- check that output device can support outputSampleFormat, or that
we have the capability to convert from outputSampleFormat to
a native format
- if outputStreamInfo is supplied, validate its contents,
or return an error if no outputStreamInfo is expected
- if a full duplex stream is requested, check that the combination
of input and output parameters is supported
- check that the device supports sampleRate
- alter sampleRate to a close allowable rate if necessary
- validate inputLatency and outputLatency
- validate any platform specific flags, if flags are supplied they
must be valid.
Referenced by Pa_OpenStream(), PaAudioIO_Initialize(), PaMacCore_Initialize(), and PaSkeleton_Initialize().
| PaUtilPrivatePaFrontHostApiInfo PaUtilHostApiRepresentation::privatePaFrontInfo |
Referenced by PaUtil_DeviceIndexToHostApiDeviceIndex().
| void(* PaUtilHostApiRepresentation::Terminate)(struct PaUtilHostApiRepresentation *hostApi) |
(*Terminate)() is guaranteed to be called with a valid <hostApi> parameter, which was previously returned from the same implementation's initializer.
Referenced by PaAudioIO_Initialize(), PaMacCore_Initialize(), and PaSkeleton_Initialize().
1.8.5