1use anyhow::{Context as _, Result, anyhow};
2
3use cpal::traits::{DeviceTrait, HostTrait, StreamTrait as _};
4use futures::channel::mpsc::UnboundedSender;
5use futures::{Stream, StreamExt as _};
6use gpui::{
7 BackgroundExecutor, ScreenCaptureFrame, ScreenCaptureSource, ScreenCaptureStream, Task,
8};
9use libwebrtc::native::{apm, audio_mixer, audio_resampler};
10use livekit::track;
11
12use livekit::webrtc::{
13 audio_frame::AudioFrame,
14 audio_source::{AudioSourceOptions, RtcAudioSource, native::NativeAudioSource},
15 audio_stream::native::NativeAudioStream,
16 video_frame::{VideoBuffer, VideoFrame, VideoRotation},
17 video_source::{RtcVideoSource, VideoResolution, native::NativeVideoSource},
18 video_stream::native::NativeVideoStream,
19};
20use parking_lot::Mutex;
21use std::cell::RefCell;
22use std::sync::Weak;
23use std::sync::atomic::{self, AtomicI32};
24use std::time::Duration;
25use std::{borrow::Cow, collections::VecDeque, sync::Arc, thread};
26use util::{ResultExt as _, maybe};
27
28pub(crate) struct AudioStack {
29 executor: BackgroundExecutor,
30 apm: Arc<Mutex<apm::AudioProcessingModule>>,
31 mixer: Arc<Mutex<audio_mixer::AudioMixer>>,
32 _output_task: RefCell<Weak<Task<()>>>,
33 next_ssrc: AtomicI32,
34}
35
36// NOTE: We use WebRTC's mixer which only supports
37// 16kHz, 32kHz and 48kHz. As 48 is the most common "next step up"
38// for audio output devices like speakers/bluetooth, we just hard-code
39// this; and downsample when we need to.
40const SAMPLE_RATE: u32 = 48000;
41const NUM_CHANNELS: u32 = 2;
42
43impl AudioStack {
44 pub(crate) fn new(executor: BackgroundExecutor) -> Self {
45 let apm = Arc::new(Mutex::new(apm::AudioProcessingModule::new(
46 true, true, true, true,
47 )));
48 let mixer = Arc::new(Mutex::new(audio_mixer::AudioMixer::new()));
49 Self {
50 executor,
51 apm,
52 mixer,
53 _output_task: RefCell::new(Weak::new()),
54 next_ssrc: AtomicI32::new(1),
55 }
56 }
57
58 pub(crate) fn play_remote_audio_track(
59 &self,
60 track: &livekit::track::RemoteAudioTrack,
61 ) -> AudioStream {
62 let output_task = self.start_output();
63
64 let next_ssrc = self.next_ssrc.fetch_add(1, atomic::Ordering::Relaxed);
65 let source = AudioMixerSource {
66 ssrc: next_ssrc,
67 sample_rate: SAMPLE_RATE,
68 num_channels: NUM_CHANNELS,
69 buffer: Arc::default(),
70 };
71 self.mixer.lock().add_source(source.clone());
72
73 let mut stream = NativeAudioStream::new(
74 track.rtc_track(),
75 source.sample_rate as i32,
76 source.num_channels as i32,
77 );
78
79 let receive_task = self.executor.spawn({
80 let source = source.clone();
81 async move {
82 while let Some(frame) = stream.next().await {
83 source.receive(frame);
84 }
85 }
86 });
87
88 let mixer = self.mixer.clone();
89 let on_drop = util::defer(move || {
90 mixer.lock().remove_source(source.ssrc);
91 drop(receive_task);
92 drop(output_task);
93 });
94
95 AudioStream::Output {
96 _drop: Box::new(on_drop),
97 }
98 }
99
100 pub(crate) fn capture_local_microphone_track(
101 &self,
102 ) -> Result<(crate::LocalAudioTrack, AudioStream)> {
103 let source = NativeAudioSource::new(
104 // n.b. this struct's options are always ignored, noise cancellation is provided by apm.
105 AudioSourceOptions::default(),
106 SAMPLE_RATE,
107 NUM_CHANNELS,
108 10,
109 );
110
111 let track = track::LocalAudioTrack::create_audio_track(
112 "microphone",
113 RtcAudioSource::Native(source.clone()),
114 );
115
116 let apm = self.apm.clone();
117
118 let (frame_tx, mut frame_rx) = futures::channel::mpsc::unbounded();
119 let transmit_task = self.executor.spawn({
120 let source = source.clone();
121 async move {
122 while let Some(frame) = frame_rx.next().await {
123 source.capture_frame(&frame).await.log_err();
124 }
125 }
126 });
127 let capture_task = self.executor.spawn(async move {
128 Self::capture_input(apm, frame_tx, SAMPLE_RATE, NUM_CHANNELS).await
129 });
130
131 let on_drop = util::defer(|| {
132 drop(transmit_task);
133 drop(capture_task);
134 });
135 return Ok((
136 super::LocalAudioTrack(track),
137 AudioStream::Output {
138 _drop: Box::new(on_drop),
139 },
140 ));
141 }
142
143 fn start_output(&self) -> Arc<Task<()>> {
144 if let Some(task) = self._output_task.borrow().upgrade() {
145 return task;
146 }
147 let task = Arc::new(self.executor.spawn({
148 let apm = self.apm.clone();
149 let mixer = self.mixer.clone();
150 async move {
151 Self::play_output(apm, mixer, SAMPLE_RATE, NUM_CHANNELS)
152 .await
153 .log_err();
154 }
155 }));
156 *self._output_task.borrow_mut() = Arc::downgrade(&task);
157 task
158 }
159
160 async fn play_output(
161 apm: Arc<Mutex<apm::AudioProcessingModule>>,
162 mixer: Arc<Mutex<audio_mixer::AudioMixer>>,
163 sample_rate: u32,
164 num_channels: u32,
165 ) -> Result<()> {
166 loop {
167 let mut device_change_listener = DeviceChangeListener::new(false)?;
168 let (output_device, output_config) = default_device(false)?;
169 let (end_on_drop_tx, end_on_drop_rx) = std::sync::mpsc::channel::<()>();
170 let mixer = mixer.clone();
171 let apm = apm.clone();
172 let mut resampler = audio_resampler::AudioResampler::default();
173 let mut buf = Vec::new();
174
175 thread::spawn(move || {
176 let output_stream = output_device.build_output_stream(
177 &output_config.config(),
178 {
179 move |mut data, _info| {
180 while data.len() > 0 {
181 if data.len() <= buf.len() {
182 let rest = buf.split_off(data.len());
183 data.copy_from_slice(&buf);
184 buf = rest;
185 return;
186 }
187 if buf.len() > 0 {
188 let (prefix, suffix) = data.split_at_mut(buf.len());
189 prefix.copy_from_slice(&buf);
190 data = suffix;
191 }
192
193 let mut mixer = mixer.lock();
194 let mixed = mixer.mix(output_config.channels() as usize);
195 let sampled = resampler.remix_and_resample(
196 mixed,
197 sample_rate / 100,
198 num_channels,
199 sample_rate,
200 output_config.channels() as u32,
201 output_config.sample_rate().0,
202 );
203 buf = sampled.to_vec();
204 apm.lock()
205 .process_reverse_stream(
206 &mut buf,
207 output_config.sample_rate().0 as i32,
208 output_config.channels() as i32,
209 )
210 .ok();
211 }
212 }
213 },
214 |error| log::error!("error playing audio track: {:?}", error),
215 Some(Duration::from_millis(100)),
216 );
217
218 let Some(output_stream) = output_stream.log_err() else {
219 return;
220 };
221
222 output_stream.play().log_err();
223 // Block forever to keep the output stream alive
224 end_on_drop_rx.recv().ok();
225 });
226
227 device_change_listener.next().await;
228 drop(end_on_drop_tx)
229 }
230 }
231
232 async fn capture_input(
233 apm: Arc<Mutex<apm::AudioProcessingModule>>,
234 frame_tx: UnboundedSender<AudioFrame<'static>>,
235 sample_rate: u32,
236 num_channels: u32,
237 ) -> Result<()> {
238 loop {
239 let mut device_change_listener = DeviceChangeListener::new(true)?;
240 let (device, config) = default_device(true)?;
241 let (end_on_drop_tx, end_on_drop_rx) = std::sync::mpsc::channel::<()>();
242 let apm = apm.clone();
243 let frame_tx = frame_tx.clone();
244 let mut resampler = audio_resampler::AudioResampler::default();
245
246 thread::spawn(move || {
247 maybe!({
248 if let Some(name) = device.name().ok() {
249 log::info!("Using microphone: {}", name)
250 } else {
251 log::info!("Using microphone: <unknown>");
252 }
253
254 let ten_ms_buffer_size =
255 (config.channels() as u32 * config.sample_rate().0 / 100) as usize;
256 let mut buf: Vec<i16> = Vec::with_capacity(ten_ms_buffer_size);
257
258 let stream = device
259 .build_input_stream_raw(
260 &config.config(),
261 cpal::SampleFormat::I16,
262 move |data, _: &_| {
263 let mut data = data.as_slice::<i16>().unwrap();
264 while data.len() > 0 {
265 let remainder = (buf.capacity() - buf.len()).min(data.len());
266 buf.extend_from_slice(&data[..remainder]);
267 data = &data[remainder..];
268
269 if buf.capacity() == buf.len() {
270 let mut sampled = resampler
271 .remix_and_resample(
272 buf.as_slice(),
273 config.sample_rate().0 / 100,
274 config.channels() as u32,
275 config.sample_rate().0,
276 num_channels,
277 sample_rate,
278 )
279 .to_owned();
280 apm.lock()
281 .process_stream(
282 &mut sampled,
283 sample_rate as i32,
284 num_channels as i32,
285 )
286 .log_err();
287 buf.clear();
288 frame_tx
289 .unbounded_send(AudioFrame {
290 data: Cow::Owned(sampled),
291 sample_rate,
292 num_channels,
293 samples_per_channel: sample_rate / 100,
294 })
295 .ok();
296 }
297 }
298 },
299 |err| log::error!("error capturing audio track: {:?}", err),
300 Some(Duration::from_millis(100)),
301 )
302 .context("failed to build input stream")?;
303
304 stream.play()?;
305 // Keep the thread alive and holding onto the `stream`
306 end_on_drop_rx.recv().ok();
307 anyhow::Ok(Some(()))
308 })
309 .log_err();
310 });
311
312 device_change_listener.next().await;
313 drop(end_on_drop_tx)
314 }
315 }
316}
317
318use super::LocalVideoTrack;
319
320pub enum AudioStream {
321 Input { _task: Task<()> },
322 Output { _drop: Box<dyn std::any::Any> },
323}
324
325pub(crate) async fn capture_local_video_track(
326 capture_source: &dyn ScreenCaptureSource,
327 cx: &mut gpui::AsyncApp,
328) -> Result<(crate::LocalVideoTrack, Box<dyn ScreenCaptureStream>)> {
329 let resolution = capture_source.resolution()?;
330 let track_source = gpui_tokio::Tokio::spawn(cx, async move {
331 NativeVideoSource::new(VideoResolution {
332 width: resolution.width.0 as u32,
333 height: resolution.height.0 as u32,
334 })
335 })?
336 .await?;
337
338 let capture_stream = capture_source
339 .stream(cx.foreground_executor(), {
340 let track_source = track_source.clone();
341 Box::new(move |frame| {
342 if let Some(buffer) = video_frame_buffer_to_webrtc(frame) {
343 track_source.capture_frame(&VideoFrame {
344 rotation: VideoRotation::VideoRotation0,
345 timestamp_us: 0,
346 buffer,
347 });
348 }
349 })
350 })
351 .await??;
352
353 Ok((
354 LocalVideoTrack(track::LocalVideoTrack::create_video_track(
355 "screen share",
356 RtcVideoSource::Native(track_source),
357 )),
358 capture_stream,
359 ))
360}
361
362fn default_device(input: bool) -> Result<(cpal::Device, cpal::SupportedStreamConfig)> {
363 let device;
364 let config;
365 if input {
366 device = cpal::default_host()
367 .default_input_device()
368 .ok_or_else(|| anyhow!("no audio input device available"))?;
369 config = device
370 .default_input_config()
371 .context("failed to get default input config")?;
372 } else {
373 device = cpal::default_host()
374 .default_output_device()
375 .ok_or_else(|| anyhow!("no audio output device available"))?;
376 config = device
377 .default_output_config()
378 .context("failed to get default output config")?;
379 }
380 Ok((device, config))
381}
382
383#[derive(Clone)]
384struct AudioMixerSource {
385 ssrc: i32,
386 sample_rate: u32,
387 num_channels: u32,
388 buffer: Arc<Mutex<VecDeque<Vec<i16>>>>,
389}
390
391impl AudioMixerSource {
392 fn receive(&self, frame: AudioFrame) {
393 assert_eq!(
394 frame.data.len() as u32,
395 self.sample_rate * self.num_channels / 100
396 );
397
398 let mut buffer = self.buffer.lock();
399 buffer.push_back(frame.data.to_vec());
400 while buffer.len() > 10 {
401 buffer.pop_front();
402 }
403 }
404}
405
406impl libwebrtc::native::audio_mixer::AudioMixerSource for AudioMixerSource {
407 fn ssrc(&self) -> i32 {
408 self.ssrc
409 }
410
411 fn preferred_sample_rate(&self) -> u32 {
412 self.sample_rate
413 }
414
415 fn get_audio_frame_with_info<'a>(&self, target_sample_rate: u32) -> Option<AudioFrame> {
416 assert_eq!(self.sample_rate, target_sample_rate);
417 let buf = self.buffer.lock().pop_front()?;
418 Some(AudioFrame {
419 data: Cow::Owned(buf),
420 sample_rate: self.sample_rate,
421 num_channels: self.num_channels,
422 samples_per_channel: self.sample_rate / 100,
423 })
424 }
425}
426
427pub fn play_remote_video_track(
428 track: &crate::RemoteVideoTrack,
429) -> impl Stream<Item = RemoteVideoFrame> + use<> {
430 #[cfg(target_os = "macos")]
431 {
432 let mut pool = None;
433 let most_recent_frame_size = (0, 0);
434 NativeVideoStream::new(track.0.rtc_track()).filter_map(move |frame| {
435 if pool == None
436 || most_recent_frame_size != (frame.buffer.width(), frame.buffer.height())
437 {
438 pool = create_buffer_pool(frame.buffer.width(), frame.buffer.height()).log_err();
439 }
440 let pool = pool.clone();
441 async move {
442 if frame.buffer.width() < 10 && frame.buffer.height() < 10 {
443 // when the remote stops sharing, we get an 8x8 black image.
444 // In a lil bit, the unpublish will come through and close the view,
445 // but until then, don't flash black.
446 return None;
447 }
448
449 video_frame_buffer_from_webrtc(pool?, frame.buffer)
450 }
451 })
452 }
453 #[cfg(not(target_os = "macos"))]
454 {
455 NativeVideoStream::new(track.0.rtc_track())
456 .filter_map(|frame| async move { video_frame_buffer_from_webrtc(frame.buffer) })
457 }
458}
459
460#[cfg(target_os = "macos")]
461fn create_buffer_pool(
462 width: u32,
463 height: u32,
464) -> Result<core_video::pixel_buffer_pool::CVPixelBufferPool> {
465 use core_foundation::{base::TCFType, number::CFNumber, string::CFString};
466 use core_video::pixel_buffer;
467 use core_video::{
468 pixel_buffer::kCVPixelFormatType_420YpCbCr8BiPlanarFullRange,
469 pixel_buffer_io_surface::kCVPixelBufferIOSurfaceCoreAnimationCompatibilityKey,
470 pixel_buffer_pool::{self},
471 };
472
473 let width_key: CFString =
474 unsafe { CFString::wrap_under_get_rule(pixel_buffer::kCVPixelBufferWidthKey) };
475 let height_key: CFString =
476 unsafe { CFString::wrap_under_get_rule(pixel_buffer::kCVPixelBufferHeightKey) };
477 let animation_key: CFString = unsafe {
478 CFString::wrap_under_get_rule(kCVPixelBufferIOSurfaceCoreAnimationCompatibilityKey)
479 };
480 let format_key: CFString =
481 unsafe { CFString::wrap_under_get_rule(pixel_buffer::kCVPixelBufferPixelFormatTypeKey) };
482
483 let yes: CFNumber = 1.into();
484 let width: CFNumber = (width as i32).into();
485 let height: CFNumber = (height as i32).into();
486 let format: CFNumber = (kCVPixelFormatType_420YpCbCr8BiPlanarFullRange as i64).into();
487
488 let buffer_attributes = core_foundation::dictionary::CFDictionary::from_CFType_pairs(&[
489 (width_key, width.into_CFType()),
490 (height_key, height.into_CFType()),
491 (animation_key, yes.into_CFType()),
492 (format_key, format.into_CFType()),
493 ]);
494
495 pixel_buffer_pool::CVPixelBufferPool::new(None, Some(&buffer_attributes)).map_err(|cv_return| {
496 anyhow!(
497 "failed to create pixel buffer pool: CVReturn({})",
498 cv_return
499 )
500 })
501}
502
503#[cfg(target_os = "macos")]
504pub type RemoteVideoFrame = core_video::pixel_buffer::CVPixelBuffer;
505
506#[cfg(target_os = "macos")]
507fn video_frame_buffer_from_webrtc(
508 pool: core_video::pixel_buffer_pool::CVPixelBufferPool,
509 buffer: Box<dyn VideoBuffer>,
510) -> Option<RemoteVideoFrame> {
511 use core_foundation::base::TCFType;
512 use core_video::{pixel_buffer::CVPixelBuffer, r#return::kCVReturnSuccess};
513 use livekit::webrtc::native::yuv_helper::i420_to_nv12;
514
515 if let Some(native) = buffer.as_native() {
516 let pixel_buffer = native.get_cv_pixel_buffer();
517 if pixel_buffer.is_null() {
518 return None;
519 }
520 return unsafe { Some(CVPixelBuffer::wrap_under_get_rule(pixel_buffer as _)) };
521 }
522
523 let i420_buffer = buffer.as_i420()?;
524 let pixel_buffer = pool.create_pixel_buffer().log_err()?;
525
526 let image_buffer = unsafe {
527 if pixel_buffer.lock_base_address(0) != kCVReturnSuccess {
528 return None;
529 }
530
531 let dst_y = pixel_buffer.get_base_address_of_plane(0);
532 let dst_y_stride = pixel_buffer.get_bytes_per_row_of_plane(0);
533 let dst_y_len = pixel_buffer.get_height_of_plane(0) * dst_y_stride;
534 let dst_uv = pixel_buffer.get_base_address_of_plane(1);
535 let dst_uv_stride = pixel_buffer.get_bytes_per_row_of_plane(1);
536 let dst_uv_len = pixel_buffer.get_height_of_plane(1) * dst_uv_stride;
537 let width = pixel_buffer.get_width();
538 let height = pixel_buffer.get_height();
539 let dst_y_buffer = std::slice::from_raw_parts_mut(dst_y as *mut u8, dst_y_len);
540 let dst_uv_buffer = std::slice::from_raw_parts_mut(dst_uv as *mut u8, dst_uv_len);
541
542 let (stride_y, stride_u, stride_v) = i420_buffer.strides();
543 let (src_y, src_u, src_v) = i420_buffer.data();
544 i420_to_nv12(
545 src_y,
546 stride_y,
547 src_u,
548 stride_u,
549 src_v,
550 stride_v,
551 dst_y_buffer,
552 dst_y_stride as u32,
553 dst_uv_buffer,
554 dst_uv_stride as u32,
555 width as i32,
556 height as i32,
557 );
558
559 if pixel_buffer.unlock_base_address(0) != kCVReturnSuccess {
560 return None;
561 }
562
563 pixel_buffer
564 };
565
566 Some(image_buffer)
567}
568
569#[cfg(not(target_os = "macos"))]
570pub type RemoteVideoFrame = Arc<gpui::RenderImage>;
571
572#[cfg(not(target_os = "macos"))]
573fn video_frame_buffer_from_webrtc(buffer: Box<dyn VideoBuffer>) -> Option<RemoteVideoFrame> {
574 use gpui::RenderImage;
575 use image::{Frame, RgbaImage};
576 use livekit::webrtc::prelude::VideoFormatType;
577 use smallvec::SmallVec;
578 use std::alloc::{Layout, alloc};
579
580 let width = buffer.width();
581 let height = buffer.height();
582 let stride = width * 4;
583 let byte_len = (stride * height) as usize;
584 let argb_image = unsafe {
585 // Motivation for this unsafe code is to avoid initializing the frame data, since to_argb
586 // will write all bytes anyway.
587 let start_ptr = alloc(Layout::array::<u8>(byte_len).log_err()?);
588 if start_ptr.is_null() {
589 return None;
590 }
591 let bgra_frame_slice = std::slice::from_raw_parts_mut(start_ptr, byte_len);
592 buffer.to_argb(
593 VideoFormatType::ARGB, // For some reason, this displays correctly while RGBA (the correct format) does not
594 bgra_frame_slice,
595 stride,
596 width as i32,
597 height as i32,
598 );
599 Vec::from_raw_parts(start_ptr, byte_len, byte_len)
600 };
601
602 Some(Arc::new(RenderImage::new(SmallVec::from_elem(
603 Frame::new(
604 RgbaImage::from_raw(width, height, argb_image)
605 .with_context(|| "Bug: not enough bytes allocated for image.")
606 .log_err()?,
607 ),
608 1,
609 ))))
610}
611
612#[cfg(target_os = "macos")]
613fn video_frame_buffer_to_webrtc(frame: ScreenCaptureFrame) -> Option<impl AsRef<dyn VideoBuffer>> {
614 use livekit::webrtc;
615
616 let pixel_buffer = frame.0.as_concrete_TypeRef();
617 std::mem::forget(frame.0);
618 unsafe {
619 Some(webrtc::video_frame::native::NativeBuffer::from_cv_pixel_buffer(pixel_buffer as _))
620 }
621}
622
623#[cfg(any(target_os = "linux", target_os = "freebsd"))]
624fn video_frame_buffer_to_webrtc(frame: ScreenCaptureFrame) -> Option<impl AsRef<dyn VideoBuffer>> {
625 use libwebrtc::native::yuv_helper::argb_to_nv12;
626 use livekit::webrtc::prelude::NV12Buffer;
627 match frame.0 {
628 scap::frame::Frame::BGRx(frame) => {
629 let mut buffer = NV12Buffer::new(frame.width as u32, frame.height as u32);
630 let (stride_y, stride_uv) = buffer.strides();
631 let (data_y, data_uv) = buffer.data_mut();
632 argb_to_nv12(
633 &frame.data,
634 frame.width as u32 * 4,
635 data_y,
636 stride_y,
637 data_uv,
638 stride_uv,
639 frame.width,
640 frame.height,
641 );
642 Some(buffer)
643 }
644 scap::frame::Frame::YUVFrame(yuvframe) => {
645 let mut buffer = NV12Buffer::with_strides(
646 yuvframe.width as u32,
647 yuvframe.height as u32,
648 yuvframe.luminance_stride as u32,
649 yuvframe.chrominance_stride as u32,
650 );
651 let (luminance, chrominance) = buffer.data_mut();
652 luminance.copy_from_slice(yuvframe.luminance_bytes.as_slice());
653 chrominance.copy_from_slice(yuvframe.chrominance_bytes.as_slice());
654 Some(buffer)
655 }
656 _ => {
657 log::error!(
658 "Expected BGRx or YUV frame from scap screen capture but got some other format."
659 );
660 None
661 }
662 }
663}
664
665#[cfg(target_os = "windows")]
666fn video_frame_buffer_to_webrtc(_frame: ScreenCaptureFrame) -> Option<impl AsRef<dyn VideoBuffer>> {
667 None as Option<Box<dyn VideoBuffer>>
668}
669
670trait DeviceChangeListenerApi: Stream<Item = ()> + Sized {
671 fn new(input: bool) -> Result<Self>;
672}
673
674#[cfg(target_os = "macos")]
675mod macos {
676
677 use coreaudio::sys::{
678 AudioObjectAddPropertyListener, AudioObjectID, AudioObjectPropertyAddress,
679 AudioObjectRemovePropertyListener, OSStatus, kAudioHardwarePropertyDefaultInputDevice,
680 kAudioHardwarePropertyDefaultOutputDevice, kAudioObjectPropertyElementMaster,
681 kAudioObjectPropertyScopeGlobal, kAudioObjectSystemObject,
682 };
683 use futures::{StreamExt, channel::mpsc::UnboundedReceiver};
684
685 /// Implementation from: https://github.com/zed-industries/cpal/blob/fd8bc2fd39f1f5fdee5a0690656caff9a26d9d50/src/host/coreaudio/macos/property_listener.rs#L15
686 pub struct CoreAudioDefaultDeviceChangeListener {
687 rx: UnboundedReceiver<()>,
688 callback: Box<PropertyListenerCallbackWrapper>,
689 input: bool,
690 device_id: AudioObjectID, // Store the device ID to properly remove listeners
691 }
692
693 trait _AssertSend: Send {}
694 impl _AssertSend for CoreAudioDefaultDeviceChangeListener {}
695
696 struct PropertyListenerCallbackWrapper(Box<dyn FnMut() + Send>);
697
698 unsafe extern "C" fn property_listener_handler_shim(
699 _: AudioObjectID,
700 _: u32,
701 _: *const AudioObjectPropertyAddress,
702 callback: *mut ::std::os::raw::c_void,
703 ) -> OSStatus {
704 let wrapper = callback as *mut PropertyListenerCallbackWrapper;
705 unsafe { (*wrapper).0() };
706 0
707 }
708
709 impl super::DeviceChangeListenerApi for CoreAudioDefaultDeviceChangeListener {
710 fn new(input: bool) -> gpui::Result<Self> {
711 let (tx, rx) = futures::channel::mpsc::unbounded();
712
713 let callback = Box::new(PropertyListenerCallbackWrapper(Box::new(move || {
714 tx.unbounded_send(()).ok();
715 })));
716
717 // Get the current default device ID
718 let device_id = unsafe {
719 // Listen for default device changes
720 coreaudio::Error::from_os_status(AudioObjectAddPropertyListener(
721 kAudioObjectSystemObject,
722 &AudioObjectPropertyAddress {
723 mSelector: if input {
724 kAudioHardwarePropertyDefaultInputDevice
725 } else {
726 kAudioHardwarePropertyDefaultOutputDevice
727 },
728 mScope: kAudioObjectPropertyScopeGlobal,
729 mElement: kAudioObjectPropertyElementMaster,
730 },
731 Some(property_listener_handler_shim),
732 &*callback as *const _ as *mut _,
733 ))?;
734
735 // Also listen for changes to the device configuration
736 let device_id = if input {
737 let mut input_device: AudioObjectID = 0;
738 let mut prop_size = std::mem::size_of::<AudioObjectID>() as u32;
739 let result = coreaudio::sys::AudioObjectGetPropertyData(
740 kAudioObjectSystemObject,
741 &AudioObjectPropertyAddress {
742 mSelector: kAudioHardwarePropertyDefaultInputDevice,
743 mScope: kAudioObjectPropertyScopeGlobal,
744 mElement: kAudioObjectPropertyElementMaster,
745 },
746 0,
747 std::ptr::null(),
748 &mut prop_size as *mut _,
749 &mut input_device as *mut _ as *mut _,
750 );
751 if result != 0 {
752 log::warn!("Failed to get default input device ID");
753 0
754 } else {
755 input_device
756 }
757 } else {
758 let mut output_device: AudioObjectID = 0;
759 let mut prop_size = std::mem::size_of::<AudioObjectID>() as u32;
760 let result = coreaudio::sys::AudioObjectGetPropertyData(
761 kAudioObjectSystemObject,
762 &AudioObjectPropertyAddress {
763 mSelector: kAudioHardwarePropertyDefaultOutputDevice,
764 mScope: kAudioObjectPropertyScopeGlobal,
765 mElement: kAudioObjectPropertyElementMaster,
766 },
767 0,
768 std::ptr::null(),
769 &mut prop_size as *mut _,
770 &mut output_device as *mut _ as *mut _,
771 );
772 if result != 0 {
773 log::warn!("Failed to get default output device ID");
774 0
775 } else {
776 output_device
777 }
778 };
779
780 if device_id != 0 {
781 // Listen for format changes on the device
782 coreaudio::Error::from_os_status(AudioObjectAddPropertyListener(
783 device_id,
784 &AudioObjectPropertyAddress {
785 mSelector: coreaudio::sys::kAudioDevicePropertyStreamFormat,
786 mScope: if input {
787 coreaudio::sys::kAudioObjectPropertyScopeInput
788 } else {
789 coreaudio::sys::kAudioObjectPropertyScopeOutput
790 },
791 mElement: kAudioObjectPropertyElementMaster,
792 },
793 Some(property_listener_handler_shim),
794 &*callback as *const _ as *mut _,
795 ))?;
796 }
797
798 device_id
799 };
800
801 Ok(Self {
802 rx,
803 callback,
804 input,
805 device_id,
806 })
807 }
808 }
809
810 impl Drop for CoreAudioDefaultDeviceChangeListener {
811 fn drop(&mut self) {
812 unsafe {
813 // Remove the system-level property listener
814 AudioObjectRemovePropertyListener(
815 kAudioObjectSystemObject,
816 &AudioObjectPropertyAddress {
817 mSelector: if self.input {
818 kAudioHardwarePropertyDefaultInputDevice
819 } else {
820 kAudioHardwarePropertyDefaultOutputDevice
821 },
822 mScope: kAudioObjectPropertyScopeGlobal,
823 mElement: kAudioObjectPropertyElementMaster,
824 },
825 Some(property_listener_handler_shim),
826 &*self.callback as *const _ as *mut _,
827 );
828
829 // Remove the device-specific property listener if we have a valid device ID
830 if self.device_id != 0 {
831 AudioObjectRemovePropertyListener(
832 self.device_id,
833 &AudioObjectPropertyAddress {
834 mSelector: coreaudio::sys::kAudioDevicePropertyStreamFormat,
835 mScope: if self.input {
836 coreaudio::sys::kAudioObjectPropertyScopeInput
837 } else {
838 coreaudio::sys::kAudioObjectPropertyScopeOutput
839 },
840 mElement: kAudioObjectPropertyElementMaster,
841 },
842 Some(property_listener_handler_shim),
843 &*self.callback as *const _ as *mut _,
844 );
845 }
846 }
847 }
848 }
849
850 impl futures::Stream for CoreAudioDefaultDeviceChangeListener {
851 type Item = ();
852
853 fn poll_next(
854 mut self: std::pin::Pin<&mut Self>,
855 cx: &mut std::task::Context<'_>,
856 ) -> std::task::Poll<Option<Self::Item>> {
857 self.rx.poll_next_unpin(cx)
858 }
859 }
860}
861
862#[cfg(target_os = "macos")]
863type DeviceChangeListener = macos::CoreAudioDefaultDeviceChangeListener;
864
865#[cfg(not(target_os = "macos"))]
866mod noop_change_listener {
867 use std::task::Poll;
868
869 use super::DeviceChangeListenerApi;
870
871 pub struct NoopOutputDeviceChangelistener {}
872
873 impl DeviceChangeListenerApi for NoopOutputDeviceChangelistener {
874 fn new(_input: bool) -> anyhow::Result<Self> {
875 Ok(NoopOutputDeviceChangelistener {})
876 }
877 }
878
879 impl futures::Stream for NoopOutputDeviceChangelistener {
880 type Item = ();
881
882 fn poll_next(
883 self: std::pin::Pin<&mut Self>,
884 _cx: &mut std::task::Context<'_>,
885 ) -> Poll<Option<Self::Item>> {
886 Poll::Pending
887 }
888 }
889}
890
891#[cfg(not(target_os = "macos"))]
892type DeviceChangeListener = noop_change_listener::NoopOutputDeviceChangelistener;