Simplify output / input audio device setting and getting through properties

modules/audio_device/audio_device_generic.h

@@ -136,6 +136,8 @@ class AudioDeviceGeneric {
 #endif  // WEBRTC_IOS
 
   virtual int32_t SetAudioDeviceSink(AudioDeviceSink* sink) = 0;
+  virtual int32_t GetPlayoutDevice() const { return -1; }
+  virtual int32_t GetRecordingDevice() const { return -1; }
 
   virtual void AttachAudioBuffer(AudioDeviceBuffer* audioBuffer) = 0;
 

modules/audio_device/audio_device_impl.cc

@@ -951,6 +951,20 @@ int32_t AudioDeviceModuleImpl::SetAudioDeviceSink(AudioDeviceSink* sink) const {
   return ok;
 }
 
+int32_t AudioDeviceModuleImpl::GetPlayoutDevice() const {
+  RTC_LOG(LS_INFO) << __FUNCTION__;
+  int32_t r = audio_device_->GetPlayoutDevice();
+  RTC_LOG(LS_INFO) << "output: " << r;
+  return r;
+}
+
+int32_t AudioDeviceModuleImpl::GetRecordingDevice() const {
+  RTC_LOG(LS_INFO) << __FUNCTION__;
+  int32_t r = audio_device_->GetRecordingDevice();
+  RTC_LOG(LS_INFO) << "output: " << r;
+  return r;
+}
+
 AudioDeviceModuleImpl::PlatformType AudioDeviceModuleImpl::Platform() const {
   RTC_LOG(LS_INFO) << __FUNCTION__;
   return platform_type_;

modules/audio_device/audio_device_impl.h

@@ -147,6 +147,8 @@ class AudioDeviceModuleImpl : public AudioDeviceModuleForTest {
 #endif  // WEBRTC_IOS
 
   int32_t SetAudioDeviceSink(AudioDeviceSink* sink) const override;
+  int32_t GetPlayoutDevice() const override;
+  int32_t GetRecordingDevice() const override;
 
 #if defined(WEBRTC_ANDROID)
   // Only use this acccessor for test purposes on Android.

modules/audio_device/include/audio_device.h

@@ -168,6 +168,8 @@ class AudioDeviceModule : public rtc::RefCountInterface {
 #endif  // WEBRTC_IOS
 
   virtual int32_t SetAudioDeviceSink(AudioDeviceSink* sink) const = 0;
+  virtual int32_t GetPlayoutDevice() const { return -1; }
+  virtual int32_t GetRecordingDevice() const { return -1; }
 
  protected:
   ~AudioDeviceModule() override {}

modules/audio_device/mac/audio_device_mac.cc

@@ -795,6 +795,14 @@ int16_t AudioDeviceMac::PlayoutDevices() {
                           MaxNumberDevices);
 }
 
+int32_t AudioDeviceMac::GetPlayoutDevice() const {  
+  if (_outputDeviceIsSpecified) {
+    return _outputDeviceIndex;
+  }
+
+  return 0;
+}
+
 int32_t AudioDeviceMac::SetPlayoutDevice(uint16_t index) {
   MutexLock lock(&mutex_);
 
@@ -869,6 +877,14 @@ int16_t AudioDeviceMac::RecordingDevices() {
                           MaxNumberDevices);
 }
 
+int32_t AudioDeviceMac::GetRecordingDevice() const {
+  if (_inputDeviceIsSpecified) {
+    return _inputDeviceIndex;
+  }
+
+  return 0;
+}
+
 int32_t AudioDeviceMac::SetRecordingDevice(uint16_t index) {
   if (_recIsInitialized) {
     return -1;

modules/audio_device/mac/audio_device_mac.h

@@ -158,6 +158,8 @@ class AudioDeviceMac : public AudioDeviceGeneric {
     audio_device_module_sink_ = sink;
     return 0;
   }
+  virtual int32_t GetPlayoutDevice() const;
+  virtual int32_t GetRecordingDevice() const;
 
  private:
   int32_t InitSpeakerLocked() RTC_EXCLUSIVE_LOCKS_REQUIRED(mutex_);

sdk/objc/api/peerconnection/RTCAudioDeviceModule.h

@@ -33,9 +33,14 @@ RTC_OBJC_EXPORT
 @property(nonatomic, readonly) BOOL playing;
 @property(nonatomic, readonly) BOOL recording;
 
+@property(nonatomic, assign) RTC_OBJC_TYPE(RTCAudioDevice) *outputDevice;
+@property(nonatomic, assign) RTC_OBJC_TYPE(RTCAudioDevice) *inputDevice;
+
 // Executes low-level API's in sequence to switch the device
-- (BOOL)setOutputDevice: (nullable RTCAudioDevice *)device;
-- (BOOL)setInputDevice: (nullable RTCAudioDevice *)device;
+// Use outputDevice / inputDevice property unless you need to know if setting the device is
+// successful.
+- (BOOL)trySetOutputDevice:(nullable RTCAudioDevice *)device;
+- (BOOL)trySetInputDevice:(nullable RTCAudioDevice *)device;
 
 - (BOOL)setDevicesUpdatedHandler: (nullable RTCOnAudioDevicesDidUpdate) handler;
 

sdk/objc/api/peerconnection/RTCAudioDeviceModule.mm

@@ -78,7 +78,27 @@ - (instancetype)initWithNativeModule:(rtc::scoped_refptr<webrtc::AudioDeviceModu
   });
 }
 
-- (BOOL)setOutputDevice: (nullable RTCAudioDevice *)device {
+- (RTCAudioDevice *)outputDevice {
+
+  return _workerThread->Invoke<RTC_OBJC_TYPE(RTCAudioDevice) *>(RTC_FROM_HERE, [self] {
+
+    NSArray<RTC_OBJC_TYPE(RTCAudioDevice) *> *devices = [self _outputDevices];
+    int16_t devicesCount = (int16_t)([devices count]);
+    int16_t index = _native->GetPlayoutDevice();
+
+    if (devicesCount == 0 || index <= -1 || index > (devicesCount - 1)) {
+      return (RTC_OBJC_TYPE(RTCAudioDevice) *)nil;
+    }
+
+    return (RTC_OBJC_TYPE(RTCAudioDevice) *)[devices objectAtIndex:index];
+  });
+}
+
+- (void)setOutputDevice: (RTCAudioDevice *)device {
+  [self trySetOutputDevice: device];
+}
+
+- (BOOL)trySetOutputDevice: (RTCAudioDevice *)device {
 
   return _workerThread->Invoke<BOOL>(RTC_FROM_HERE, [self, device] {
 
@@ -111,7 +131,27 @@ - (BOOL)setOutputDevice: (nullable RTCAudioDevice *)device {
   });
 }
 
-- (BOOL)setInputDevice: (nullable RTCAudioDevice *)device {
+- (RTCAudioDevice *)inputDevice {
+
+  return _workerThread->Invoke<RTC_OBJC_TYPE(RTCAudioDevice) *>(RTC_FROM_HERE, [self] {
+
+    NSArray<RTC_OBJC_TYPE(RTCAudioDevice) *> *devices = [self _inputDevices];
+    int16_t devicesCount = (int16_t)([devices count]);
+    int16_t index = _native->GetRecordingDevice();
+
+    if (devicesCount == 0 || index <= -1 || index > (devicesCount - 1)) {
+      return (RTC_OBJC_TYPE(RTCAudioDevice) *)nil;
+    }
+
+    return (RTC_OBJC_TYPE(RTCAudioDevice) *)[devices objectAtIndex:index];
+  });
+}
+
+- (void)setInputDevice: (RTCAudioDevice *)device {
+  [self trySetInputDevice: device];
+}
+
+- (BOOL)trySetInputDevice: (RTCAudioDevice *)device {
 
   return _workerThread->Invoke<BOOL>(RTC_FROM_HERE, [self, device] {