From 3978e1eb2cb0a25ff5c9d2a6bf47999f8843330d Mon Sep 17 00:00:00 2001
From: Jordan Woyak <jordan.woyak@gmail.com>
Date: Thu, 2 Oct 2025 04:11:27 -0500
Subject: [PATCH] WindowsDevice: Add some utility functions for getting device
 properties using CfgMgr32.

---
 Source/Core/Common/WindowsDevice.cpp | 49 ++++++++++++++++++++++++++++
 Source/Core/Common/WindowsDevice.h   |  8 +++++
 2 files changed, 57 insertions(+)

diff --git a/Source/Core/Common/WindowsDevice.cpp b/Source/Core/Common/WindowsDevice.cpp
index 8ecc346187..770aa3861a 100644
--- a/Source/Core/Common/WindowsDevice.cpp
+++ b/Source/Core/Common/WindowsDevice.cpp
@@ -7,7 +7,10 @@
 
 #include <string>
 
+#include "Hidclass.h"
+
 #include "Common/CommonFuncs.h"
+#include "Common/Logging/Log.h"
 
 namespace Common
 {
@@ -33,6 +36,52 @@ std::wstring GetDeviceProperty(const HDEVINFO& device_info, const PSP_DEVINFO_DA
 
   return std::wstring(unicode_buffer.data());
 }
+
+std::optional<std::wstring> GetPropertyHelper(auto function, auto dev,
+                                              const DEVPROPKEY* requested_property,
+                                              DEVPROPTYPE expected_type)
+{
+  DEVPROPTYPE type{};
+  ULONG buffer_size{};
+
+  if (const auto result = function(dev, requested_property, &type, nullptr, &buffer_size, 0);
+      result != CR_SUCCESS && result != CR_BUFFER_SMALL)
+  {
+    WARN_LOG_FMT(COMMON, "CM_Get_DevNode_Property returned: {}", result);
+    return std::nullopt;
+  }
+  if (type != expected_type)
+  {
+    WARN_LOG_FMT(COMMON, "CM_Get_DevNode_Property unexpected type: 0x{:x}", type);
+    return std::nullopt;
+  }
+
+  std::optional<std::wstring> property;
+  // FYI: It's legal to write the null terminator at data()[size()] of std::basic_string.
+  property.emplace(buffer_size / sizeof(WCHAR) - 1, L'\0');
+  if (const auto result = function(dev, requested_property, &type,
+                                   reinterpret_cast<BYTE*>(property->data()), &buffer_size, 0);
+      result != CR_SUCCESS)
+  {
+    ERROR_LOG_FMT(COMMON, "CM_Get_DevNode_Property returned: {}", result);
+    return std::nullopt;
+  }
+  return property;
+}
+
+std::optional<std::wstring> GetDevNodeStringProperty(DEVINST dev,
+                                                     const DEVPROPKEY* requested_property)
+{
+  return GetPropertyHelper(CM_Get_DevNode_Property, dev, requested_property, DEVPROP_TYPE_STRING);
+}
+
+std::optional<std::wstring> GetDeviceInterfaceStringProperty(LPCWSTR iface,
+                                                             const DEVPROPKEY* requested_property)
+{
+  return GetPropertyHelper(CM_Get_Device_Interface_Property, iface, requested_property,
+                           DEVPROP_TYPE_STRING);
+}
+
 }  // namespace Common
 
 #endif
diff --git a/Source/Core/Common/WindowsDevice.h b/Source/Core/Common/WindowsDevice.h
index c79e9b0d7a..463c6299b4 100644
--- a/Source/Core/Common/WindowsDevice.h
+++ b/Source/Core/Common/WindowsDevice.h
@@ -5,6 +5,7 @@
 
 #ifdef _WIN32
 
+#include <optional>
 #include <string>
 
 #ifndef WIN32_LEAN_AND_MEAN
@@ -24,6 +25,13 @@ namespace Common
 // Obtains a device property and returns it as a wide string.
 std::wstring GetDeviceProperty(const HANDLE& device_info, const PSP_DEVINFO_DATA device_data,
                                const DEVPROPKEY* requested_property);
+
+std::optional<std::wstring> GetDevNodeStringProperty(DEVINST device,
+                                                     const DEVPROPKEY* requested_property);
+
+std::optional<std::wstring> GetDeviceInterfaceStringProperty(LPCWSTR iface,
+                                                             const DEVPROPKEY* requested_property);
+
 }  // namespace Common
 
 #endif