From d4a7a79ace02c3b1e25849b8a5ea9e29a2a6c264 Mon Sep 17 00:00:00 2001
From: Diederick Niehorster <dcnieho@gmail.com>
Date: Fri, 14 May 2021 21:00:39 +0200
Subject: [PATCH] Add fallback for getting device path.

---
 source/dshow-base.hpp |  1 +
 source/dshow-enum.cpp | 24 ++++++++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/source/dshow-base.hpp b/source/dshow-base.hpp
index 5e90f8d..04313e7 100644
--- a/source/dshow-base.hpp
+++ b/source/dshow-base.hpp
@@ -28,6 +28,7 @@
 #include <ksproxy.h>
 #include <Amaudio.h>
 #include <Dvdmedia.h>
+#include <Propvarutil.h>
 
 #include "ComPtr.hpp"
 #include "CoTaskMemPtr.hpp"
diff --git a/source/dshow-enum.cpp b/source/dshow-enum.cpp
index 9dc104f..3205038 100644
--- a/source/dshow-enum.cpp
+++ b/source/dshow-enum.cpp
@@ -473,6 +473,30 @@ static bool EnumDevice(const GUID &type, IMoniker *deviceInfo,
 	}
 
 	propertyData->Read(L"DevicePath", &devicePath, NULL);
+	if (!devicePath.bstrVal) {
+		/* fall back to another method to get device path */
+		LPMALLOC co_malloc = nullptr;
+		hr = CoGetMalloc(1, &co_malloc);
+		if (FAILED(hr))
+			return true;
+
+		ComPtr<IBindCtx> bind_ctx = nullptr;
+		hr = CreateBindCtx(0, &bind_ctx);
+		if (FAILED(hr))
+			return true;
+
+		LPOLESTR olestr = nullptr;
+		bool success = true;
+		hr = deviceInfo->GetDisplayName(bind_ctx, nullptr, &olestr);
+		if (SUCCEEDED(hr)) {
+			hr = InitVariantFromString(olestr, &devicePath);
+			if (FAILED(hr))
+				success = false;
+		}
+		co_malloc->Free(olestr);
+		if (!success)
+			return true;
+	}
 
 	hr = deviceInfo->BindToObject(NULL, 0, IID_IBaseFilter,
 				      (void **)&filter);