#4652 webrtc crash when switching devices

Author: akleshchev

indra/llwebrtc/llwebrtc.cpp

@@ -484,9 +484,9 @@ void LLWebRTCImpl::workerDeployDevices()
         }
     }
 
-    mDeviceModule->StopPlayout();
     mDeviceModule->ForceStopRecording();
 #if WEBRTC_WIN
+    mDeviceModule->StopPlayout();
     if (recordingDevice < 0)
     {
         mDeviceModule->SetRecordingDevice((webrtc::AudioDeviceModule::WindowsDeviceType)recordingDevice);
@@ -496,6 +496,8 @@ void LLWebRTCImpl::workerDeployDevices()
         mDeviceModule->SetRecordingDevice(recordingDevice);
     }
 #else
+    // Calls own StopPlayout from AudioDeviceMac::HandleDeviceChange()
+    // Don't call twice, StopPlayout's Finalize isn't thread safe
     mDeviceModule->SetRecordingDevice(recordingDevice);
 #endif
     mDeviceModule->InitMicrophone();
@@ -576,8 +578,22 @@ void LLWebRTCImpl::setCaptureDevice(const std::string &id)
     deployDevices();
 }
 
-void LLWebRTCImpl::setRenderDevice(const std::string &id)
+void LLWebRTCImpl::setRenderDevice(const std::string &id, bool stop_playout)
 {
+#if !WEBRTC_WIN
+    // Workaround for a macOS crash
+    // Due to insecure StopPlayout call, can't call StopPlayout from
+    // workerDeployDevices, nor can use ForceStopPlayout()
+    // For now only call StopPlayout when switching devices from preferences
+    if (stop_playout)
+    {
+        mWorkerThread->BlockingCall(
+            [this]
+        {
+            mDeviceModule->StopPlayout();
+        });
+    }
+#endif
     mPlayoutDevice = id;
     deployDevices();
 }

indra/llwebrtc/llwebrtc.h

@@ -149,7 +149,7 @@ class LLWebRTCDeviceInterface
 
     // set the capture and render devices using the unique identifier for the device
     virtual void setCaptureDevice(const std::string& id) = 0;
-    virtual void setRenderDevice(const std::string& id) = 0;
+    virtual void setRenderDevice(const std::string& id, bool stop_playout) = 0;
     virtual void setDevices(const std::string& caprure_id, const std::string& render_id) = 0;
 
     // Device observers for device change callbacks.

indra/llwebrtc/llwebrtc_impl.h

@@ -442,7 +442,7 @@ class LLWebRTCImpl : public LLWebRTCDeviceInterface, public webrtc::AudioDeviceO
     void unsetDevicesObserver(LLWebRTCDevicesObserver *observer) override;
 
     void setCaptureDevice(const std::string& id) override;
-    void setRenderDevice(const std::string& id) override;
+    void setRenderDevice(const std::string& id, bool stop_playout) override;
     void setDevices(const std::string& caprure_id, const std::string& render_id) override;
 
     void setTuningMode(bool enable) override;

indra/newview/llvoicewebrtc.cpp

@@ -779,7 +779,11 @@ void LLWebRTCVoiceClient::OnDevicesChangedImpl(const llwebrtc::LLWebRTCVoiceDevi
     }
     else if (update_render)
     {
-        setRenderDevice(outputDevice);
+        if (mWebRTCDeviceInterface)
+        {
+            LL_DEBUGS("Voice") << "new render device is " << outputDevice << LL_ENDL;
+            mWebRTCDeviceInterface->setRenderDevice(outputDevice, false);
+        }
     }
     else if (update_capture)
     {
@@ -812,7 +816,7 @@ void LLWebRTCVoiceClient::setRenderDevice(const std::string& name)
     if (mWebRTCDeviceInterface)
     {
         LL_DEBUGS("Voice") << "new render device is " << name << LL_ENDL;
-        mWebRTCDeviceInterface->setRenderDevice(name);
+        mWebRTCDeviceInterface->setRenderDevice(name, true);
     }
 }