1/*
2 * Copyright 2018 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ANDROID_JAUDIOTRACK_H
18#define ANDROID_JAUDIOTRACK_H
19
20#include <jni.h>
21#include <media/AudioResamplerPublic.h>
22#include <media/AudioSystem.h>
23#include <media/VolumeShaper.h>
24#include <system/audio.h>
25#include <utils/Errors.h>
26
27#include <media/AudioTimestamp.h>   // It has dependency on audio.h/Errors.h, but doesn't
28                                    // include them in it. Therefore it is included here at last.
29
30namespace android {
31
32class JAudioTrack {
33public:
34
35    /* Events used by AudioTrack callback function (callback_t).
36     * Keep in sync with frameworks/base/media/java/android/media/AudioTrack.java NATIVE_EVENT_*.
37     */
38    enum event_type {
39        EVENT_MORE_DATA = 0,        // Request to write more data to buffer.
40        EVENT_NEW_IAUDIOTRACK = 6,  // IAudioTrack was re-created, either due to re-routing and
41                                    // voluntary invalidation by mediaserver, or mediaserver crash.
42        EVENT_STREAM_END = 7,       // Sent after all the buffers queued in AF and HW are played
43                                    // back (after stop is called) for an offloaded track.
44    };
45
46    class Buffer
47    {
48    public:
49        size_t      mSize;        // input/output in bytes.
50        void*       mData;        // pointer to the audio data.
51    };
52
53    /* As a convenience, if a callback is supplied, a handler thread
54     * is automatically created with the appropriate priority. This thread
55     * invokes the callback when a new buffer becomes available or various conditions occur.
56     *
57     * Parameters:
58     *
59     * event:   type of event notified (see enum AudioTrack::event_type).
60     * user:    Pointer to context for use by the callback receiver.
61     * info:    Pointer to optional parameter according to event type:
62     *          - EVENT_MORE_DATA: pointer to JAudioTrack::Buffer struct. The callback must not
63     *            write more bytes than indicated by 'size' field and update 'size' if fewer bytes
64     *            are written.
65     *          - EVENT_NEW_IAUDIOTRACK: unused.
66     *          - EVENT_STREAM_END: unused.
67     */
68
69    typedef void (*callback_t)(int event, void* user, void *info);
70
71    /* Creates an JAudioTrack object for non-offload mode.
72     * Once created, the track needs to be started before it can be used.
73     * Unspecified values are set to appropriate default values.
74     *
75     * Parameters:
76     *
77     * streamType:         Select the type of audio stream this track is attached to
78     *                     (e.g. AUDIO_STREAM_MUSIC).
79     * sampleRate:         Data source sampling rate in Hz.  Zero means to use the sink sample rate.
80     *                     A non-zero value must be specified if AUDIO_OUTPUT_FLAG_DIRECT is set.
81     *                     0 will not work with current policy implementation for direct output
82     *                     selection where an exact match is needed for sampling rate.
83     *                     (TODO: Check direct output after flags can be used in Java AudioTrack.)
84     * format:             Audio format. For mixed tracks, any PCM format supported by server is OK.
85     *                     For direct and offloaded tracks, the possible format(s) depends on the
86     *                     output sink.
87     *                     (TODO: How can we check whether a format is supported?)
88     * channelMask:        Channel mask, such that audio_is_output_channel(channelMask) is true.
89     * cbf:                Callback function. If not null, this function is called periodically
90     *                     to provide new data and inform of marker, position updates, etc.
91     * user:               Context for use by the callback receiver.
92     * frameCount:         Minimum size of track PCM buffer in frames. This defines the
93     *                     application's contribution to the latency of the track.
94     *                     The actual size selected by the JAudioTrack could be larger if the
95     *                     requested size is not compatible with current audio HAL configuration.
96     *                     Zero means to use a default value.
97     * sessionId:          Specific session ID, or zero to use default.
98     * pAttributes:        If not NULL, supersedes streamType for use case selection.
99     * maxRequiredSpeed:   For PCM tracks, this creates an appropriate buffer size that will allow
100     *                     maxRequiredSpeed playback. Values less than 1.0f and greater than
101     *                     AUDIO_TIMESTRETCH_SPEED_MAX will be clamped.  For non-PCM tracks
102     *                     and direct or offloaded tracks, this parameter is ignored.
103     *                     (TODO: Handle this after offload / direct track is supported.)
104     *
105     * TODO: Revive removed arguments after offload mode is supported.
106     */
107    JAudioTrack(audio_stream_type_t streamType,
108                uint32_t sampleRate,
109                audio_format_t format,
110                audio_channel_mask_t channelMask,
111                callback_t cbf,
112                void* user,
113                size_t frameCount = 0,
114                audio_session_t sessionId  = AUDIO_SESSION_ALLOCATE,
115                const audio_attributes_t* pAttributes = NULL,
116                float maxRequiredSpeed = 1.0f);
117
118    /*
119       // Q. May be used in AudioTrack.setPreferredDevice(AudioDeviceInfo)?
120       audio_port_handle_t selectedDeviceId,
121
122       // TODO: No place to use these values.
123       int32_t notificationFrames,
124       const audio_offload_info_t *offloadInfo,
125    */
126
127    virtual ~JAudioTrack();
128
129    size_t frameCount();
130    size_t channelCount();
131
132    /* Returns this track's estimated latency in milliseconds.
133     * This includes the latency due to AudioTrack buffer size, AudioMixer (if any)
134     * and audio hardware driver.
135     */
136    uint32_t latency();
137
138    /* Return the total number of frames played since playback start.
139     * The counter will wrap (overflow) periodically, e.g. every ~27 hours at 44.1 kHz.
140     * It is reset to zero by flush(), reload(), and stop().
141     *
142     * Parameters:
143     *
144     * position: Address where to return play head position.
145     *
146     * Returned status (from utils/Errors.h) can be:
147     *  - NO_ERROR: successful operation
148     *  - BAD_VALUE: position is NULL
149     */
150    status_t getPosition(uint32_t *position);
151
152    // TODO: Does this comment apply same to Java AudioTrack::getTimestamp?
153    // Changed the return type from status_t to bool, since Java AudioTrack::getTimestamp returns
154    // boolean. Will Java getTimestampWithStatus() be public?
155    /* Poll for a timestamp on demand.
156     * Use if EVENT_NEW_TIMESTAMP is not delivered often enough for your needs,
157     * or if you need to get the most recent timestamp outside of the event callback handler.
158     * Caution: calling this method too often may be inefficient;
159     * if you need a high resolution mapping between frame position and presentation time,
160     * consider implementing that at application level, based on the low resolution timestamps.
161     * Returns true if timestamp is valid.
162     * The timestamp parameter is undefined on return, if false is returned.
163     */
164    bool getTimestamp(AudioTimestamp& timestamp);
165
166    // TODO: This doc is just copied from AudioTrack.h. Revise it after implemenation.
167    /* Return the extended timestamp, with additional timebase info and improved drain behavior.
168     *
169     * This is similar to the AudioTrack.java API:
170     * getTimestamp(@NonNull AudioTimestamp timestamp, @AudioTimestamp.Timebase int timebase)
171     *
172     * Some differences between this method and the getTimestamp(AudioTimestamp& timestamp) method
173     *
174     *   1. stop() by itself does not reset the frame position.
175     *      A following start() resets the frame position to 0.
176     *   2. flush() by itself does not reset the frame position.
177     *      The frame position advances by the number of frames flushed,
178     *      when the first frame after flush reaches the audio sink.
179     *   3. BOOTTIME clock offsets are provided to help synchronize with
180     *      non-audio streams, e.g. sensor data.
181     *   4. Position is returned with 64 bits of resolution.
182     *
183     * Parameters:
184     *  timestamp: A pointer to the caller allocated ExtendedTimestamp.
185     *
186     * Returns NO_ERROR    on success; timestamp is filled with valid data.
187     *         BAD_VALUE   if timestamp is NULL.
188     *         WOULD_BLOCK if called immediately after start() when the number
189     *                     of frames consumed is less than the
190     *                     overall hardware latency to physical output. In WOULD_BLOCK cases,
191     *                     one might poll again, or use getPosition(), or use 0 position and
192     *                     current time for the timestamp.
193     *                     If WOULD_BLOCK is returned, the timestamp is still
194     *                     modified with the LOCATION_CLIENT portion filled.
195     *         DEAD_OBJECT if AudioFlinger dies or the output device changes and
196     *                     the track cannot be automatically restored.
197     *                     The application needs to recreate the AudioTrack
198     *                     because the audio device changed or AudioFlinger died.
199     *                     This typically occurs for direct or offloaded tracks
200     *                     or if mDoNotReconnect is true.
201     *         INVALID_OPERATION  if called on a offloaded or direct track.
202     *                     Use getTimestamp(AudioTimestamp& timestamp) instead.
203     */
204    status_t getTimestamp(ExtendedTimestamp *timestamp);
205
206    /* Set source playback rate for timestretch
207     * 1.0 is normal speed: < 1.0 is slower, > 1.0 is faster
208     * 1.0 is normal pitch: < 1.0 is lower pitch, > 1.0 is higher pitch
209     *
210     * AUDIO_TIMESTRETCH_SPEED_MIN <= speed <= AUDIO_TIMESTRETCH_SPEED_MAX
211     * AUDIO_TIMESTRETCH_PITCH_MIN <= pitch <= AUDIO_TIMESTRETCH_PITCH_MAX
212     *
213     * Speed increases the playback rate of media, but does not alter pitch.
214     * Pitch increases the "tonal frequency" of media, but does not affect the playback rate.
215     */
216    status_t setPlaybackRate(const AudioPlaybackRate &playbackRate);
217
218    /* Return current playback rate */
219    const AudioPlaybackRate getPlaybackRate();
220
221    /* Sets the volume shaper object */
222    media::VolumeShaper::Status applyVolumeShaper(
223            const sp<media::VolumeShaper::Configuration>& configuration,
224            const sp<media::VolumeShaper::Operation>& operation);
225
226    /* Set the send level for this track. An auxiliary effect should be attached
227     * to the track with attachEffect(). Level must be >= 0.0 and <= 1.0.
228     */
229    status_t setAuxEffectSendLevel(float level);
230
231    /* Attach track auxiliary output to specified effect. Use effectId = 0
232     * to detach track from effect.
233     *
234     * Parameters:
235     *
236     * effectId: effectId obtained from AudioEffect::id().
237     *
238     * Returned status (from utils/Errors.h) can be:
239     *  - NO_ERROR: successful operation
240     *  - INVALID_OPERATION: The effect is not an auxiliary effect.
241     *  - BAD_VALUE: The specified effect ID is invalid.
242     */
243    status_t attachAuxEffect(int effectId);
244
245    /* Set volume for this track, mostly used for games' sound effects
246     * left and right volumes. Levels must be >= 0.0 and <= 1.0.
247     * This is the older API.  New applications should use setVolume(float) when possible.
248     */
249    status_t setVolume(float left, float right);
250
251    /* Set volume for all channels. This is the preferred API for new applications,
252     * especially for multi-channel content.
253     */
254    status_t setVolume(float volume);
255
256    // TODO: Does this comment equally apply to the Java AudioTrack::play()?
257    /* After it's created the track is not active. Call start() to
258     * make it active. If set, the callback will start being called.
259     * If the track was previously paused, volume is ramped up over the first mix buffer.
260     */
261    status_t start();
262
263    // TODO: Does this comment still applies? It seems not. (obtainBuffer, AudioFlinger, ...)
264    /* As a convenience we provide a write() interface to the audio buffer.
265     * Input parameter 'size' is in byte units.
266     * This is implemented on top of obtainBuffer/releaseBuffer. For best
267     * performance use callbacks. Returns actual number of bytes written >= 0,
268     * or one of the following negative status codes:
269     *      INVALID_OPERATION   AudioTrack is configured for static buffer or streaming mode
270     *      BAD_VALUE           size is invalid
271     *      WOULD_BLOCK         when obtainBuffer() returns same, or
272     *                          AudioTrack was stopped during the write
273     *      DEAD_OBJECT         when AudioFlinger dies or the output device changes and
274     *                          the track cannot be automatically restored.
275     *                          The application needs to recreate the AudioTrack
276     *                          because the audio device changed or AudioFlinger died.
277     *                          This typically occurs for direct or offload tracks
278     *                          or if mDoNotReconnect is true.
279     *      or any other error code returned by IAudioTrack::start() or restoreTrack_l().
280     * Default behavior is to only return when all data has been transferred. Set 'blocking' to
281     * false for the method to return immediately without waiting to try multiple times to write
282     * the full content of the buffer.
283     */
284    ssize_t write(const void* buffer, size_t size, bool blocking = true);
285
286    // TODO: Does this comment equally apply to the Java AudioTrack::stop()?
287    /* Stop a track.
288     * In static buffer mode, the track is stopped immediately.
289     * In streaming mode, the callback will cease being called.  Note that obtainBuffer() still
290     * works and will fill up buffers until the pool is exhausted, and then will return WOULD_BLOCK.
291     * In streaming mode the stop does not occur immediately: any data remaining in the buffer
292     * is first drained, mixed, and output, and only then is the track marked as stopped.
293     */
294    void stop();
295    bool stopped() const;
296
297    // TODO: Does this comment equally apply to the Java AudioTrack::flush()?
298    /* Flush a stopped or paused track. All previously buffered data is discarded immediately.
299     * This has the effect of draining the buffers without mixing or output.
300     * Flush is intended for streaming mode, for example before switching to non-contiguous content.
301     * This function is a no-op if the track is not stopped or paused, or uses a static buffer.
302     */
303    void flush();
304
305    // TODO: Does this comment equally apply to the Java AudioTrack::pause()?
306    // At least we are not using obtainBuffer.
307    /* Pause a track. After pause, the callback will cease being called and
308     * obtainBuffer returns WOULD_BLOCK. Note that obtainBuffer() still works
309     * and will fill up buffers until the pool is exhausted.
310     * Volume is ramped down over the next mix buffer following the pause request,
311     * and then the track is marked as paused. It can be resumed with ramp up by start().
312     */
313    void pause();
314
315    bool isPlaying() const;
316
317    /* Return current source sample rate in Hz.
318     * If specified as zero in constructor, this will be the sink sample rate.
319     */
320    uint32_t getSampleRate();
321
322    /* Returns the buffer duration in microseconds at current playback rate. */
323    status_t getBufferDurationInUs(int64_t *duration);
324
325    audio_format_t format();
326
327    /*
328     * Dumps the state of an audio track.
329     * Not a general-purpose API; intended only for use by media player service to dump its tracks.
330     */
331    status_t dump(int fd, const Vector<String16>& args) const;
332
333    /* Returns the ID of the audio device actually used by the output to which this AudioTrack is
334     * attached. When the AudioTrack is inactive, it will return AUDIO_PORT_HANDLE_NONE.
335     */
336    audio_port_handle_t getRoutedDeviceId();
337
338    /* Returns the ID of the audio session this AudioTrack belongs to. */
339    audio_session_t getAudioSessionId();
340
341    /* Selects the audio device to use for output of this AudioTrack. A value of
342     * AUDIO_PORT_HANDLE_NONE indicates default routing.
343     *
344     * Parameters:
345     *  The device ID of the selected device (as returned by the AudioDevicesManager API).
346     *
347     * Returned value:
348     *  - NO_ERROR: successful operation
349     *  - BAD_VALUE: failed to find the valid output device with given device Id.
350     */
351    status_t setOutputDevice(audio_port_handle_t deviceId);
352
353    // TODO: Add AUDIO_OUTPUT_FLAG_DIRECT when it is possible to check.
354    // TODO: Add AUDIO_FLAG_HW_AV_SYNC when it is possible to check.
355    /* Returns the flags */
356    audio_output_flags_t getFlags() const { return mFlags; }
357
358    /* Obtain the pending duration in milliseconds for playback of pure PCM data remaining in
359     * AudioTrack.
360     *
361     * Returns NO_ERROR if successful.
362     *         INVALID_OPERATION if the AudioTrack does not contain pure PCM data.
363     *         BAD_VALUE if msec is nullptr.
364     */
365    status_t pendingDuration(int32_t *msec);
366
367    /* Adds an AudioDeviceCallback. The caller will be notified when the audio device to which this
368     * AudioTrack is routed is updated.
369     * Replaces any previously installed callback.
370     *
371     * Parameters:
372     *
373     * callback: The callback interface
374     *
375     * Returns NO_ERROR if successful.
376     *         INVALID_OPERATION if the same callback is already installed.
377     *         NO_INIT or PREMISSION_DENIED if AudioFlinger service is not reachable
378     *         BAD_VALUE if the callback is NULL
379     */
380    status_t addAudioDeviceCallback(const sp<AudioSystem::AudioDeviceCallback>& callback);
381
382    /* Removes an AudioDeviceCallback.
383     *
384     * Parameters:
385     *
386     * callback: The callback interface
387     *
388     * Returns NO_ERROR if successful.
389     *         INVALID_OPERATION if the callback is not installed
390     *         BAD_VALUE if the callback is NULL
391     */
392    status_t removeAudioDeviceCallback(const sp<AudioSystem::AudioDeviceCallback>& callback);
393
394private:
395    audio_output_flags_t mFlags;
396
397    jclass mAudioTrackCls;
398    jobject mAudioTrackObj;
399
400    /* Creates a Java VolumeShaper.Configuration object from VolumeShaper::Configuration */
401    jobject createVolumeShaperConfigurationObj(
402            const sp<media::VolumeShaper::Configuration>& config);
403
404    /* Creates a Java VolumeShaper.Operation object from VolumeShaper::Operation */
405    jobject createVolumeShaperOperationObj(
406            const sp<media::VolumeShaper::Operation>& operation);
407
408    /* Creates a Java StreamEventCallback object */
409    jobject createStreamEventCallback(callback_t cbf, void* user);
410
411    /* Creates a Java Executor object for running a callback */
412    jobject createCallbackExecutor();
413
414    status_t javaToNativeStatus(int javaStatus);
415};
416
417}; // namespace android
418
419#endif // ANDROID_JAUDIOTRACK_H
420