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/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* This is the 'C' ABI for Oboe.
*/
#ifndef OBOE_OBOEAUDIO_H
#define OBOE_OBOEAUDIO_H
#include "OboeDefinitions.h"
#ifdef __cplusplus
extern "C" {
#endif
typedef oboe_handle_t OboeStream;
typedef oboe_handle_t OboeStreamBuilder;
#define OBOE_STREAM_NONE ((OboeStream)OBOE_HANDLE_INVALID)
#define OBOE_STREAM_BUILDER_NONE ((OboeStreamBuilder)OBOE_HANDLE_INVALID)
/* OBOE_API will probably get defined in a Makefile for a specific platform. */
#ifndef OBOE_API
#define OBOE_API /* for exporting symbols */
#endif
// ============================================================
// Audio System
// ============================================================
/**
* @return time in the same clock domain as the timestamps
*/
OBOE_API oboe_nanoseconds_t Oboe_getNanoseconds(oboe_clockid_t clockid);
/**
* The text is the ASCII symbol corresponding to the returnCode,
* or an English message saying the returnCode is unrecognized.
* This is intended for developers to use when debugging.
* It is not for display to users.
*
* @return pointer to a text representation of an Oboe result code.
*/
OBOE_API const char * Oboe_convertResultToText(oboe_result_t returnCode);
/**
* The text is the ASCII symbol corresponding to the stream state,
* or an English message saying the state is unrecognized.
* This is intended for developers to use when debugging.
* It is not for display to users.
*
* @return pointer to a text representation of an Oboe state.
*/
OBOE_API const char * Oboe_convertStreamStateToText(oboe_stream_state_t state);
// ============================================================
// StreamBuilder
// ============================================================
/**
* Create a StreamBuilder that can be used to open a Stream.
*
* The deviceId is initially unspecified, meaning that the current default device will be used.
*
* The default direction is OBOE_DIRECTION_OUTPUT.
* The default sharing mode is OBOE_SHARING_MODE_LEGACY.
* The data format, samplesPerFrames and sampleRate are unspecified and will be
* chosen by the device when it is opened.
*
* OboeStreamBuilder_delete() must be called when you are done using the builder.
*/
OBOE_API oboe_result_t Oboe_createStreamBuilder(OboeStreamBuilder *builder);
/**
* Request an audio device identified device using an ID.
* The ID is platform specific.
* On Android, for example, the ID could be obtained from the Java AudioManager.
*
* By default, the primary device will be used.
*
* @param builder handle provided by Oboe_createStreamBuilder()
* @param deviceId platform specific identifier or OBOE_DEVICE_UNSPECIFIED
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStreamBuilder_setDeviceId(OboeStreamBuilder builder,
oboe_device_id_t deviceId);
/**
* Passes back requested device ID.
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStreamBuilder_getDeviceId(OboeStreamBuilder builder,
oboe_device_id_t *deviceId);
/**
* Request a sample rate in Hz.
* The stream may be opened with a different sample rate.
* So the application should query for the actual rate after the stream is opened.
*
* Technically, this should be called the "frame rate" or "frames per second",
* because it refers to the number of complete frames transferred per second.
* But it is traditionally called "sample rate". Se we use that term.
*
* Default is OBOE_UNSPECIFIED.
*
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStreamBuilder_setSampleRate(OboeStreamBuilder builder,
oboe_sample_rate_t sampleRate);
/**
* Returns sample rate in Hertz (samples per second).
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStreamBuilder_getSampleRate(OboeStreamBuilder builder,
oboe_sample_rate_t *sampleRate);
/**
* Request a number of samples per frame.
* The stream may be opened with a different value.
* So the application should query for the actual value after the stream is opened.
*
* Default is OBOE_UNSPECIFIED.
*
* Note, this quantity is sometimes referred to as "channel count".
*
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStreamBuilder_setSamplesPerFrame(OboeStreamBuilder builder,
int32_t samplesPerFrame);
/**
* Note, this quantity is sometimes referred to as "channel count".
*
* @param builder handle provided by Oboe_createStreamBuilder()
* @param samplesPerFrame pointer to a variable to be set to samplesPerFrame.
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStreamBuilder_getSamplesPerFrame(OboeStreamBuilder builder,
int32_t *samplesPerFrame);
/**
* Request a sample data format, for example OBOE_AUDIO_FORMAT_PCM16.
* The application should query for the actual format after the stream is opened.
*
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStreamBuilder_setFormat(OboeStreamBuilder builder,
oboe_audio_format_t format);
/**
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStreamBuilder_getFormat(OboeStreamBuilder builder,
oboe_audio_format_t *format);
/**
* Request a mode for sharing the device.
* The requested sharing mode may not be available.
* So the application should query for the actual mode after the stream is opened.
*
* @param builder handle provided by Oboe_createStreamBuilder()
* @param sharingMode OBOE_SHARING_MODE_LEGACY or OBOE_SHARING_MODE_EXCLUSIVE
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStreamBuilder_setSharingMode(OboeStreamBuilder builder,
oboe_sharing_mode_t sharingMode);
/**
* Return requested sharing mode.
* @return OBOE_OK or a negative error
*/
OBOE_API oboe_result_t OboeStreamBuilder_getSharingMode(OboeStreamBuilder builder,
oboe_sharing_mode_t *sharingMode);
/**
* Request the direction for a stream. The default is OBOE_DIRECTION_OUTPUT.
*
* @param builder handle provided by Oboe_createStreamBuilder()
* @param direction OBOE_DIRECTION_OUTPUT or OBOE_DIRECTION_INPUT
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStreamBuilder_setDirection(OboeStreamBuilder builder,
oboe_direction_t direction);
/**
* @param builder handle provided by Oboe_createStreamBuilder()
* @param direction pointer to a variable to be set to the currently requested direction.
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStreamBuilder_getDirection(OboeStreamBuilder builder,
oboe_direction_t *direction);
/**
* Open a stream based on the options in the StreamBuilder.
*
* OboeStream_close must be called when finished with the stream to recover
* the memory and to free the associated resources.
*
* @param builder handle provided by Oboe_createStreamBuilder()
* @param stream pointer to a variable to receive the new stream handle
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStreamBuilder_openStream(OboeStreamBuilder builder,
OboeStream *stream);
/**
* Delete the resources associated with the StreamBuilder.
*
* @param builder handle provided by Oboe_createStreamBuilder()
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStreamBuilder_delete(OboeStreamBuilder builder);
// ============================================================
// Stream Control
// ============================================================
/**
* Free the resources associated with a stream created by OboeStreamBuilder_openStream()
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_close(OboeStream stream);
/**
* Asynchronously request to start playing the stream. For output streams, one should
* write to the stream to fill the buffer before starting.
* Otherwise it will underflow.
* After this call the state will be in OBOE_STREAM_STATE_STARTING or OBOE_STREAM_STATE_STARTED.
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_requestStart(OboeStream stream);
/**
* Asynchronous request for the stream to pause.
* Pausing a stream will freeze the data flow but not flush any buffers.
* Use OboeStream_Start() to resume playback after a pause.
* After this call the state will be in OBOE_STREAM_STATE_PAUSING or OBOE_STREAM_STATE_PAUSED.
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_requestPause(OboeStream stream);
/**
* Asynchronous request for the stream to flush.
* Flushing will discard any pending data.
* This call only works if the stream is pausing or paused. TODO review
* Frame counters are not reset by a flush. They may be advanced.
* After this call the state will be in OBOE_STREAM_STATE_FLUSHING or OBOE_STREAM_STATE_FLUSHED.
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_requestFlush(OboeStream stream);
/**
* Asynchronous request for the stream to stop.
* The stream will stop after all of the data currently buffered has been played.
* After this call the state will be in OBOE_STREAM_STATE_STOPPING or OBOE_STREAM_STATE_STOPPED.
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_requestStop(OboeStream stream);
/**
* Query the current state, eg. OBOE_STREAM_STATE_PAUSING
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param state pointer to a variable that will be set to the current state
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_getState(OboeStream stream, oboe_stream_state_t *state);
/**
* Wait until the current state no longer matches the input state.
*
* <pre><code>
* oboe_stream_state_t currentState;
* oboe_result_t result = OboeStream_getState(stream, &currentState);
* while (result == OBOE_OK && currentState != OBOE_STREAM_STATE_PAUSING) {
* result = OboeStream_waitForStateChange(
* stream, currentState, &currentState, MY_TIMEOUT_NANOS);
* }
* </code></pre>
*
* @param stream A handle provided by OboeStreamBuilder_openStream()
* @param inputState The state we want to avoid.
* @param nextState Pointer to a variable that will be set to the new state.
* @param timeoutNanoseconds Maximum number of nanoseconds to wait for completion.
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_waitForStateChange(OboeStream stream,
oboe_stream_state_t inputState,
oboe_stream_state_t *nextState,
oboe_nanoseconds_t timeoutNanoseconds);
// ============================================================
// Stream I/O
// ============================================================
/**
* Read data from the stream.
*
* The call will wait until the read is complete or until it runs out of time.
* If timeoutNanos is zero then this call will not wait.
*
* Note that timeoutNanoseconds is a relative duration in wall clock time.
* Time will not stop if the thread is asleep.
* So it will be implemented using CLOCK_BOOTTIME.
*
* This call is "strong non-blocking" unless it has to wait for data.
*
* @param stream A stream created using OboeStreamBuilder_openStream().
* @param buffer The address of the first sample.
* @param numFrames Number of frames to read. Only complete frames will be written.
* @param timeoutNanoseconds Maximum number of nanoseconds to wait for completion.
* @return The number of frames actually written or a negative error.
*/
OBOE_API oboe_result_t OboeStream_read(OboeStream stream,
void *buffer,
oboe_size_frames_t numFrames,
oboe_nanoseconds_t timeoutNanoseconds);
/**
* Write data to the stream.
*
* The call will wait until the write is complete or until it runs out of time.
* If timeoutNanos is zero then this call will not wait.
*
* Note that timeoutNanoseconds is a relative duration in wall clock time.
* Time will not stop if the thread is asleep.
* So it will be implemented using CLOCK_BOOTTIME.
*
* This call is "strong non-blocking" unless it has to wait for room in the buffer.
*
* @param stream A stream created using OboeStreamBuilder_openStream().
* @param buffer The address of the first sample.
* @param numFrames Number of frames to write. Only complete frames will be written.
* @param timeoutNanoseconds Maximum number of nanoseconds to wait for completion.
* @return The number of frames actually written or a negative error.
*/
OBOE_API oboe_result_t OboeStream_write(OboeStream stream,
const void *buffer,
oboe_size_frames_t numFrames,
oboe_nanoseconds_t timeoutNanoseconds);
// ============================================================
// High priority audio threads
// ============================================================
typedef void *(oboe_audio_thread_proc_t)(void *);
/**
* Create a thread associated with a stream. The thread has special properties for
* low latency audio performance. This thread can be used to implement a callback API.
*
* Only one thread may be associated with a stream.
*
* Note that this API is in flux.
*
* @param stream A stream created using OboeStreamBuilder_openStream().
* @param periodNanoseconds the estimated period at which the audio thread will need to wake up
* @param startRoutine your thread entry point
* @param arg an argument that will be passed to your thread entry point
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_createThread(OboeStream stream,
oboe_nanoseconds_t periodNanoseconds,
oboe_audio_thread_proc_t *threadProc,
void *arg);
/**
* Wait until the thread exits or an error occurs.
* The thread handle will be deleted.
*
* @param stream A stream created using OboeStreamBuilder_openStream().
* @param returnArg a pointer to a variable to receive the return value
* @param timeoutNanoseconds Maximum number of nanoseconds to wait for completion.
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_joinThread(OboeStream stream,
void **returnArg,
oboe_nanoseconds_t timeoutNanoseconds);
// ============================================================
// Stream - queries
// ============================================================
/**
* This can be used to adjust the latency of the buffer by changing
* the threshold where blocking will occur.
* By combining this with OboeStream_getUnderrunCount(), the latency can be tuned
* at run-time for each device.
*
* This cannot be set higher than OboeStream_getBufferCapacity().
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param requestedFrames requested number of frames that can be filled without blocking
* @param actualFrames receives final number of frames
* @return OBOE_OK or a negative error
*/
OBOE_API oboe_result_t OboeStream_setBufferSize(OboeStream stream,
oboe_size_frames_t requestedFrames,
oboe_size_frames_t *actualFrames);
/**
* Query the maximum number of frames that can be filled without blocking.
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param frames pointer to variable to receive the buffer size
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_getBufferSize(OboeStream stream, oboe_size_frames_t *frames);
/**
* Query the number of frames that are read or written by the endpoint at one time.
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param frames pointer to variable to receive the burst size
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_getFramesPerBurst(OboeStream stream, oboe_size_frames_t *frames);
/**
* Query maximum buffer capacity in frames.
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param frames pointer to variable to receive the buffer capacity
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_getBufferCapacity(OboeStream stream, oboe_size_frames_t *frames);
/**
* An XRun is an Underrun or an Overrun.
* During playing, an underrun will occur if the stream is not written in time
* and the system runs out of valid data.
* During recording, an overrun will occur if the stream is not read in time
* and there is no place to put the incoming data so it is discarded.
*
* An underrun or overrun can cause an audible "pop" or "glitch".
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param xRunCount pointer to variable to receive the underrun or overrun count
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_getXRunCount(OboeStream stream, int32_t *xRunCount);
/**
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param sampleRate pointer to variable to receive the actual sample rate
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_getSampleRate(OboeStream stream, oboe_sample_rate_t *sampleRate);
/**
* The samplesPerFrame is also known as channelCount.
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param samplesPerFrame pointer to variable to receive the actual samples per frame
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_getSamplesPerFrame(OboeStream stream, int32_t *samplesPerFrame);
/**
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param deviceId pointer to variable to receive the actual device ID
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_getDeviceId(OboeStream stream, oboe_device_id_t *deviceId);
/**
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param format pointer to variable to receive the actual data format
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_getFormat(OboeStream stream, oboe_audio_format_t *format);
/**
* Provide actual sharing mode.
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param sharingMode pointer to variable to receive the actual sharing mode
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_getSharingMode(OboeStream stream,
oboe_sharing_mode_t *sharingMode);
/**
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param direction pointer to a variable to be set to the current direction.
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_getDirection(OboeStream stream, oboe_direction_t *direction);
/**
* Passes back the number of frames that have been written since the stream was created.
* For an output stream, this will be advanced by the application calling write().
* For an input stream, this will be advanced by the device or service.
*
* The frame position is monotonically increasing.
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param frames pointer to variable to receive the frames written
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_getFramesWritten(OboeStream stream,
oboe_position_frames_t *frames);
/**
* Passes back the number of frames that have been read since the stream was created.
* For an output stream, this will be advanced by the device or service.
* For an input stream, this will be advanced by the application calling read().
*
* The frame position is monotonically increasing.
*
* @param stream handle provided by OboeStreamBuilder_openStream()
* @param frames pointer to variable to receive the frames written
* @return OBOE_OK or a negative error.
*/
OBOE_API oboe_result_t OboeStream_getFramesRead(OboeStream stream, oboe_position_frames_t *frames);
/**
* Passes back the time at which a particular frame was presented.
* This can be used to synchronize audio with video or MIDI.
* It can also be used to align a recorded stream with a playback stream.
*
* Timestamps are only valid when the stream is in OBOE_STREAM_STATE_STARTED.
* OBOE_ERROR_INVALID_STATE will be returned if the stream is not started.
* Note that because requestStart() is asynchronous, timestamps will not be valid until
* a short time after calling requestStart().
* So OBOE_ERROR_INVALID_STATE should not be considered a fatal error.
* Just try calling again later.
*
* If an error occurs, then the position and time will not be modified.
*
* The position and time passed back are monotonically increasing.
*
* @param stream A handle provided by OboeStreamBuilder_openStream()
* @param clockid OBOE_CLOCK_MONOTONIC or OBOE_CLOCK_BOOTTIME
* @param framePosition pointer to a variable to receive the position
* @param timeNanoseconds pointer to a variable to receive the time
* @return OBOE_OK or a negative error
*/
OBOE_API oboe_result_t OboeStream_getTimestamp(OboeStream stream,
oboe_clockid_t clockid,
oboe_position_frames_t *framePosition,
oboe_nanoseconds_t *timeNanoseconds);
#ifdef __cplusplus
}
#endif
#endif //OBOE_OBOEAUDIO_H