| /* |
| * 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 AAudio. |
| */ |
| #ifndef AAUDIO_AAUDIO_H |
| #define AAUDIO_AAUDIO_H |
| |
| #include <time.h> |
| #include "AAudioDefinitions.h" |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| typedef struct AAudioStreamStruct AAudioStream; |
| typedef struct AAudioStreamBuilderStruct AAudioStreamBuilder; |
| |
| #ifndef AAUDIO_API |
| #define AAUDIO_API /* export this symbol */ |
| #endif |
| |
| // ============================================================ |
| // Audio System |
| // ============================================================ |
| |
| /** |
| * 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 AAudio result code. |
| */ |
| AAUDIO_API const char * AAudio_convertResultToText(aaudio_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 AAudio state. |
| */ |
| AAUDIO_API const char * AAudio_convertStreamStateToText(aaudio_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 AAUDIO_DIRECTION_OUTPUT. |
| * The default sharing mode is AAUDIO_SHARING_MODE_SHARED. |
| * The data format, samplesPerFrames and sampleRate are unspecified and will be |
| * chosen by the device when it is opened. |
| * |
| * AAudioStreamBuilder_delete() must be called when you are done using the builder. |
| */ |
| AAUDIO_API aaudio_result_t AAudio_createStreamBuilder(AAudioStreamBuilder** builder); |
| |
| /** |
| * Request an audio device identified device using an ID. |
| * On Android, for example, the ID could be obtained from the Java AudioManager. |
| * |
| * By default, the primary device will be used. |
| * |
| * @param builder reference provided by AAudio_createStreamBuilder() |
| * @param deviceId device identifier or AAUDIO_DEVICE_UNSPECIFIED |
| */ |
| AAUDIO_API void AAudioStreamBuilder_setDeviceId(AAudioStreamBuilder* builder, |
| int32_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 AAUDIO_UNSPECIFIED. |
| |
| */ |
| AAUDIO_API void AAudioStreamBuilder_setSampleRate(AAudioStreamBuilder* builder, |
| int32_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 AAUDIO_UNSPECIFIED. |
| * |
| * Note, this quantity is sometimes referred to as "channel count". |
| */ |
| AAUDIO_API void AAudioStreamBuilder_setSamplesPerFrame(AAudioStreamBuilder* builder, |
| int32_t samplesPerFrame); |
| |
| /** |
| * Request a sample data format, for example AAUDIO_FORMAT_PCM_I16. |
| * The application should query for the actual format after the stream is opened. |
| */ |
| AAUDIO_API void AAudioStreamBuilder_setFormat(AAudioStreamBuilder* builder, |
| aaudio_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 reference provided by AAudio_createStreamBuilder() |
| * @param sharingMode AAUDIO_SHARING_MODE_LEGACY or AAUDIO_SHARING_MODE_EXCLUSIVE |
| */ |
| AAUDIO_API void AAudioStreamBuilder_setSharingMode(AAudioStreamBuilder* builder, |
| aaudio_sharing_mode_t sharingMode); |
| |
| /** |
| * Request the direction for a stream. The default is AAUDIO_DIRECTION_OUTPUT. |
| * |
| * @param builder reference provided by AAudio_createStreamBuilder() |
| * @param direction AAUDIO_DIRECTION_OUTPUT or AAUDIO_DIRECTION_INPUT |
| */ |
| AAUDIO_API void AAudioStreamBuilder_setDirection(AAudioStreamBuilder* builder, |
| aaudio_direction_t direction); |
| |
| /** |
| * Set the requested maximum buffer capacity in frames. |
| * The final AAudioStream capacity may differ, but will probably be at least this big. |
| * |
| * Default is AAUDIO_UNSPECIFIED. |
| * |
| * @param builder reference provided by AAudio_createStreamBuilder() |
| * @param frames the desired buffer capacity in frames or AAUDIO_UNSPECIFIED |
| */ |
| AAUDIO_API void AAudioStreamBuilder_setBufferCapacityInFrames(AAudioStreamBuilder* builder, |
| int32_t frames); |
| |
| /** |
| * Open a stream based on the options in the StreamBuilder. |
| * |
| * AAudioStream_close must be called when finished with the stream to recover |
| * the memory and to free the associated resources. |
| * |
| * @param builder reference provided by AAudio_createStreamBuilder() |
| * @param stream pointer to a variable to receive the new stream reference |
| * @return AAUDIO_OK or a negative error. |
| */ |
| AAUDIO_API aaudio_result_t AAudioStreamBuilder_openStream(AAudioStreamBuilder* builder, |
| AAudioStream** stream); |
| |
| /** |
| * Delete the resources associated with the StreamBuilder. |
| * |
| * @param builder reference provided by AAudio_createStreamBuilder() |
| * @return AAUDIO_OK or a negative error. |
| */ |
| AAUDIO_API aaudio_result_t AAudioStreamBuilder_delete(AAudioStreamBuilder* builder); |
| |
| // ============================================================ |
| // Stream Control |
| // ============================================================ |
| |
| /** |
| * Free the resources associated with a stream created by AAudioStreamBuilder_openStream() |
| * |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return AAUDIO_OK or a negative error. |
| */ |
| AAUDIO_API aaudio_result_t AAudioStream_close(AAudioStream* 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 AAUDIO_STREAM_STATE_STARTING or AAUDIO_STREAM_STATE_STARTED. |
| * |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return AAUDIO_OK or a negative error. |
| */ |
| AAUDIO_API aaudio_result_t AAudioStream_requestStart(AAudioStream* stream); |
| |
| /** |
| * Asynchronous request for the stream to pause. |
| * Pausing a stream will freeze the data flow but not flush any buffers. |
| * Use AAudioStream_Start() to resume playback after a pause. |
| * After this call the state will be in AAUDIO_STREAM_STATE_PAUSING or AAUDIO_STREAM_STATE_PAUSED. |
| * |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return AAUDIO_OK or a negative error. |
| */ |
| AAUDIO_API aaudio_result_t AAudioStream_requestPause(AAudioStream* 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 AAUDIO_STREAM_STATE_FLUSHING or AAUDIO_STREAM_STATE_FLUSHED. |
| * |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return AAUDIO_OK or a negative error. |
| */ |
| AAUDIO_API aaudio_result_t AAudioStream_requestFlush(AAudioStream* 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 AAUDIO_STREAM_STATE_STOPPING or AAUDIO_STREAM_STATE_STOPPED. |
| * |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return AAUDIO_OK or a negative error. |
| */ |
| AAUDIO_API aaudio_result_t AAudioStream_requestStop(AAudioStream* stream); |
| |
| /** |
| * Query the current state of the client, eg. AAUDIO_STREAM_STATE_PAUSING |
| * |
| * This function will immediately return the state without updating the state. |
| * If you want to update the client state based on the server state then |
| * call AAudioStream_waitForStateChange() with currentState |
| * set to AAUDIO_STREAM_STATE_UNKNOWN and a zero timeout. |
| * |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @param state pointer to a variable that will be set to the current state |
| */ |
| AAUDIO_API aaudio_stream_state_t AAudioStream_getState(AAudioStream* stream); |
| |
| /** |
| * Wait until the current state no longer matches the input state. |
| * |
| * This will update the current client state. |
| * |
| * <pre><code> |
| * aaudio_stream_state_t currentState; |
| * aaudio_result_t result = AAudioStream_getState(stream, ¤tState); |
| * while (result == AAUDIO_OK && currentState != AAUDIO_STREAM_STATE_PAUSING) { |
| * result = AAudioStream_waitForStateChange( |
| * stream, currentState, ¤tState, MY_TIMEOUT_NANOS); |
| * } |
| * </code></pre> |
| * |
| * @param stream A reference provided by AAudioStreamBuilder_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 AAUDIO_OK or a negative error. |
| */ |
| AAUDIO_API aaudio_result_t AAudioStream_waitForStateChange(AAudioStream* stream, |
| aaudio_stream_state_t inputState, |
| aaudio_stream_state_t *nextState, |
| int64_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 AAudioStreamBuilder_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 read or a negative error. |
| */ |
| AAUDIO_API aaudio_result_t AAudioStream_read(AAudioStream* stream, |
| void *buffer, |
| int32_t numFrames, |
| int64_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 AAudioStreamBuilder_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. |
| */ |
| AAUDIO_API aaudio_result_t AAudioStream_write(AAudioStream* stream, |
| const void *buffer, |
| int32_t numFrames, |
| int64_t timeoutNanoseconds); |
| |
| |
| // ============================================================ |
| // High priority audio threads |
| // ============================================================ |
| |
| typedef void *(*aaudio_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. |
| * |
| * If you are using multiple streams then we recommend that you only do |
| * blocking reads or writes on one stream. You can do non-blocking I/O on the |
| * other streams by setting the timeout to zero. |
| * This thread should be created for the stream that you will block on. |
| * |
| * Note that this API is in flux. |
| * |
| * @param stream A stream created using AAudioStreamBuilder_openStream(). |
| * @param periodNanoseconds the estimated period at which the audio thread will need to wake up |
| * @param threadProc your thread entry point |
| * @param arg an argument that will be passed to your thread entry point |
| * @return AAUDIO_OK or a negative error. |
| */ |
| AAUDIO_API aaudio_result_t AAudioStream_createThread(AAudioStream* stream, |
| int64_t periodNanoseconds, |
| aaudio_audio_thread_proc_t threadProc, |
| void *arg); |
| |
| /** |
| * Wait until the thread exits or an error occurs. |
| * |
| * @param stream A stream created using AAudioStreamBuilder_openStream(). |
| * @param returnArg a pointer to a variable to receive the return value |
| * @param timeoutNanoseconds Maximum number of nanoseconds to wait for completion. |
| * @return AAUDIO_OK or a negative error. |
| */ |
| AAUDIO_API aaudio_result_t AAudioStream_joinThread(AAudioStream* stream, |
| void **returnArg, |
| int64_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 AAudioStream_getXRunCount(), the latency can be tuned |
| * at run-time for each device. |
| * |
| * This cannot be set higher than AAudioStream_getBufferCapacityInFrames(). |
| * |
| * Note that you will probably not get the exact size you request. |
| * Call AAudioStream_getBufferSizeInFrames() to see what the actual final size is. |
| * |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @param requestedFrames requested number of frames that can be filled without blocking |
| * @return actual buffer size in frames or a negative error |
| */ |
| AAUDIO_API aaudio_result_t AAudioStream_setBufferSizeInFrames(AAudioStream* stream, |
| int32_t requestedFrames); |
| |
| /** |
| * Query the maximum number of frames that can be filled without blocking. |
| * |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return buffer size in frames. |
| */ |
| AAUDIO_API int32_t AAudioStream_getBufferSizeInFrames(AAudioStream* stream); |
| |
| /** |
| * Query the number of frames that the application should read or write at |
| * one time for optimal performance. It is OK if an application writes |
| * a different number of frames. But the buffer size may need to be larger |
| * in order to avoid underruns or overruns. |
| * |
| * Note that this may or may not match the actual device burst size. |
| * For some endpoints, the burst size can vary dynamically. |
| * But these tend to be devices with high latency. |
| * |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return burst size |
| */ |
| AAUDIO_API int32_t AAudioStream_getFramesPerBurst(AAudioStream* stream); |
| |
| /** |
| * Query maximum buffer capacity in frames. |
| * |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return the buffer capacity in frames |
| */ |
| AAUDIO_API int32_t AAudioStream_getBufferCapacityInFrames(AAudioStream* stream); |
| |
| /** |
| * 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 reference provided by AAudioStreamBuilder_openStream() |
| * @return the underrun or overrun count |
| */ |
| AAUDIO_API int32_t AAudioStream_getXRunCount(AAudioStream* stream); |
| |
| /** |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return actual sample rate |
| */ |
| AAUDIO_API int32_t AAudioStream_getSampleRate(AAudioStream* stream); |
| |
| /** |
| * The samplesPerFrame is also known as channelCount. |
| * |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return actual samples per frame |
| */ |
| AAUDIO_API int32_t AAudioStream_getSamplesPerFrame(AAudioStream* stream); |
| |
| /** |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return actual device ID |
| */ |
| AAUDIO_API int32_t AAudioStream_getDeviceId(AAudioStream* stream); |
| |
| /** |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return actual data format |
| */ |
| AAUDIO_API aaudio_audio_format_t AAudioStream_getFormat(AAudioStream* stream); |
| |
| /** |
| * Provide actual sharing mode. |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return actual sharing mode |
| */ |
| AAUDIO_API aaudio_sharing_mode_t AAudioStream_getSharingMode(AAudioStream* stream); |
| |
| /** |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return direction |
| */ |
| AAUDIO_API aaudio_direction_t AAudioStream_getDirection(AAudioStream* stream); |
| |
| /** |
| * 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 endpoint. |
| * |
| * The frame position is monotonically increasing. |
| * |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return frames written |
| */ |
| AAUDIO_API int64_t AAudioStream_getFramesWritten(AAudioStream* stream); |
| |
| /** |
| * 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 endpoint. |
| * For an input stream, this will be advanced by the application calling read(). |
| * |
| * The frame position is monotonically increasing. |
| * |
| * @param stream reference provided by AAudioStreamBuilder_openStream() |
| * @return frames read |
| */ |
| AAUDIO_API int64_t AAudioStream_getFramesRead(AAudioStream* stream); |
| |
| /** |
| * 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 AAUDIO_STREAM_STATE_STARTED. |
| * AAUDIO_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 AAUDIO_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 reference provided by AAudioStreamBuilder_openStream() |
| * @param clockid AAUDIO_CLOCK_MONOTONIC or AAUDIO_CLOCK_BOOTTIME |
| * @param framePosition pointer to a variable to receive the position |
| * @param timeNanoseconds pointer to a variable to receive the time |
| * @return AAUDIO_OK or a negative error |
| */ |
| AAUDIO_API aaudio_result_t AAudioStream_getTimestamp(AAudioStream* stream, |
| clockid_t clockid, |
| int64_t *framePosition, |
| int64_t *timeNanoseconds); |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif //AAUDIO_AAUDIO_H |