Removed 'IMMNotificationClient' implementation of audio endpoint routing,

go with a polling method instead. There are bugs with
IMMNotificationClient with no apparent solution.

src/contrib/wasapiout/WasapiOut.cpp

@@ -34,6 +34,7 @@
 
 #include "WasapiOut.h"
 #include <core/sdk/constants.h>
+#include <core/sdk/IPreferences.h>
 #include <AudioSessionTypes.h>
 #include <iostream>
 #include <chrono>
@@ -41,6 +42,7 @@
 #include <algorithm>
 
 #define MAX_BUFFERS_PER_OUTPUT 16
+#define DEFAULT_DEVICE_CHECK_INTERVAL 2000
 
 /* NOTE! device init and deinit logic was stolen and modified from
 QMMP's WASAPI output plugin! http://qmmp.ylsoftware.com/ */
@@ -50,83 +52,11 @@ QMMP's WASAPI output plugin! http://qmmp.ylsoftware.com/ */
 #endif
 
 using Lock = std::unique_lock<std::recursive_mutex>;
+musik::core::sdk::IPreferences* prefs = nullptr;
 
-class NotificationClient : public IMMNotificationClient {
-    public:
-        NotificationClient(WasapiOut* owner)
-        : count(1)
-        , owner(owner)
-        , enumerator(nullptr) {
-        }
-
-        ~NotificationClient() {
-            if (this->enumerator) {
-                this->enumerator->Release();
-                this->enumerator = nullptr;
-            }
-        }
-
-        /* IUnknown methods -- AddRef, Release, and QueryInterface */
-
-        ULONG STDMETHODCALLTYPE AddRef() {
-            return InterlockedIncrement(&this->count);
-        }
-
-        ULONG STDMETHODCALLTYPE Release() {
-            ULONG newCount = InterlockedDecrement(&this->count);
-            if (0 == newCount) {
-                delete this;
-            }
-            return newCount;
-        }
-
-        HRESULT STDMETHODCALLTYPE QueryInterface(REFIID riid, VOID **ppvInterface) {
-            if (IID_IUnknown == riid) {
-                this->AddRef();
-                *ppvInterface = (IUnknown*)this;
-            }
-            else if (__uuidof(IMMNotificationClient) == riid) {
-                this->AddRef();
-                *ppvInterface = (IMMNotificationClient*)this;
-            }
-            else {
-                *ppvInterface = nullptr;
-                return E_NOINTERFACE;
-            }
-            return S_OK;
-        }
-
-        /* Callback methods for device-event notifications. */
-
-        HRESULT STDMETHODCALLTYPE OnDefaultDeviceChanged(
-            EDataFlow flow, ERole role,
-            LPCWSTR pwstrDeviceId)
-        {
-            owner->OnDeviceChanged();
-            return S_OK;
-        }
-
-        HRESULT STDMETHODCALLTYPE OnDeviceAdded(LPCWSTR pwstrDeviceId) {
-            return S_OK;
-        }
-
-        HRESULT STDMETHODCALLTYPE OnDeviceRemoved(LPCWSTR pwstrDeviceId) {
-            return S_OK;
-        }
-
-        HRESULT STDMETHODCALLTYPE OnDeviceStateChanged(LPCWSTR pwstrDeviceId, DWORD dwNewState) {
-            return S_OK;
-        }
-
-        HRESULT STDMETHODCALLTYPE OnPropertyValueChanged(LPCWSTR pwstrDeviceId, const PROPERTYKEY key){
-            return S_OK;
-        }
-
-    private:
-        LONG count;
-        IMMDeviceEnumerator *enumerator;
-        WasapiOut* owner;
-};
+extern "C" __declspec(dllexport) void SetPreferences(musik::core::sdk::IPreferences* prefs) {
+    ::prefs = prefs;
+}
 
 WasapiOut::WasapiOut()
 : enumerator(nullptr)
@@ -140,8 +70,9 @@ WasapiOut::WasapiOut()
 , outputBufferFrames(0)
 , state(StateStopped)
 , latency(0)
-, deviceChanged(false)
-, volume(1.0f) {
+, volume(1.0f)
+, lastDeviceCheck(0)
+, enableEndpointRouting(0) {
     ZeroMemory(&waveFormat, sizeof(WAVEFORMATEXTENSIBLE));
 }
 
@@ -226,6 +157,27 @@ void WasapiOut::Drain() {
     }
 }
 
+/* ideally we'd use a IMMNotificationClient callback, but it seems to
+introduce random crashing when devices are attached /detached from the
+system... but only sometimes. there are similar crashes in firefox,
+VLC, and some other apps, but no known resolution. instead we poll the
+default device every few seconds. */
+bool WasapiOut::DefaultDeviceChanged() {
+    IMMDevice* currentDevice;
+    if (this->enumerator && this->enumerator->GetDefaultAudioEndpoint(eRender, eConsole, &currentDevice) == S_OK) {
+        wchar_t* dev1 = nullptr;
+        wchar_t* dev2 = nullptr;
+        this->device->GetId(&dev1);
+        currentDevice->GetId(&dev2);
+        bool changed = lstrcmpW(dev1, dev2) != 0;
+        CoTaskMemFree(dev1);
+        CoTaskMemFree(dev2);
+        currentDevice->Release();
+        return changed;
+    }
+    return false;
+}
+
 int WasapiOut::Play(IBuffer *buffer, IBufferProvider *provider) {
     Lock lock(this->stateMutex);
 
@@ -233,10 +185,15 @@ int WasapiOut::Play(IBuffer *buffer, IBufferProvider *provider) {
         return OutputInvalidState;
     }
 
-    if (this->deviceChanged) {
-        this->Reset();
-        this->deviceChanged = false;
-        return OutputFormatError;
+    if (this->enableEndpointRouting) {
+        DWORD now = GetTickCount();
+        if (now - this->lastDeviceCheck > DEFAULT_DEVICE_CHECK_INTERVAL) {
+            lastDeviceCheck = now;
+            if (this->DefaultDeviceChanged()) {
+                this->Reset();
+                return OutputFormatError;
+            }
+        }
     }
 
     if (!this->Configure(buffer)) {
@@ -274,6 +231,10 @@ int WasapiOut::Play(IBuffer *buffer, IBufferProvider *provider) {
 }
 
 void WasapiOut::Reset() {
+    if (this->audioClient) {
+        this->audioClient->Stop();
+    }
+
     if (this->simpleAudioVolume) {
         this->simpleAudioVolume->Release();
         this->simpleAudioVolume = nullptr;
@@ -302,16 +263,10 @@ void WasapiOut::Reset() {
 
     if (this->device) {
         this->device->Release();
-        this->device = 0;
+        this->device = nullptr;
     }
 
     if (this->enumerator) {
-        if (this->notificationClient) {
-            this->enumerator->UnregisterEndpointNotificationCallback(this->notificationClient);
-            this->notificationClient->Release();
-            this->notificationClient = nullptr;
-        }
-
         this->enumerator->Release();
         this->enumerator = nullptr;
     }
@@ -344,12 +299,6 @@ bool WasapiOut::Configure(IBuffer *buffer) {
             return false;
         }
 
-        this->notificationClient = new NotificationClient(this);
-
-        if ((result = this->enumerator->RegisterEndpointNotificationCallback(this->notificationClient)) != S_OK) {
-            return false;
-        }
-
         if ((result = this->device->Activate(__uuidof(IAudioClient), CLSCTX_ALL, NULL, (void**) &this->audioClient)) != S_OK) {
             return false;
         }
@@ -361,6 +310,10 @@ bool WasapiOut::Configure(IBuffer *buffer) {
         return true;
     }
 
+    if (::prefs) {
+        this->enableEndpointRouting = prefs->GetBool("enable_audio_endpoint_routing", true);
+    }
+
     DWORD speakerConfig = 0;
     switch (buffer->Channels()) {
         case 1:

src/contrib/wasapiout/WasapiOut.h

@@ -68,8 +68,6 @@ class WasapiOut : public IOutput {
         virtual double Latency();
         virtual void Drain();
 
-        void OnDeviceChanged() { this->deviceChanged = true; }
-
     private:
         enum State {
             StateStopped,
@@ -78,6 +76,7 @@ class WasapiOut : public IOutput {
         };
 
         bool Configure(IBuffer *buffer);
+        bool DefaultDeviceChanged();
         void Reset();
 
         IMMDeviceEnumerator *enumerator;
@@ -94,6 +93,7 @@ class WasapiOut : public IOutput {
         double volume;
         double latency;
         int rate;
-        bool deviceChanged;
+        DWORD lastDeviceCheck;
+        bool enableEndpointRouting;
         std::recursive_mutex stateMutex;
 };

src/contrib/wasapiout/wasapiout_plugin.cpp

@@ -36,6 +36,7 @@
 
 #include <core/sdk/constants.h>
 #include <core/sdk/IPlugin.h>
+#include <core/sdk/IPreferences.h>
 #include "WasapiOut.h"
 
 class WasapiPlugin : public musik::core::sdk::IPlugin {
@@ -58,3 +59,5 @@ extern "C" __declspec(dllexport) musik::core::sdk::IPlugin* GetPlugin() {
 extern "C" __declspec(dllexport) musik::core::sdk::IOutput* GetAudioOutput() {
     return new WasapiOut();
 }
+
+extern "C" __declspec(dllexport) void SetPreferences(musik::core::sdk::IPreferences* prefs);