InputCommon: Add Pipes InputBackend class.

Source/Core/InputCommon/ControllerInterface/ControllerInterface.cpp

@@ -77,7 +77,7 @@ void ControllerInterface::Initialize(const WindowSystemInfo& wsi)
   m_input_backends.emplace_back(ciface::evdev::CreateInputBackend(this));
 #endif
 #ifdef CIFACE_USE_PIPES
-// nothing needed
+  m_input_backends.emplace_back(ciface::Pipes::CreateInputBackend(this));
 #endif
 #ifdef CIFACE_USE_DUALSHOCKUDPCLIENT
   m_input_backends.emplace_back(ciface::DualShockUDPClient::CreateInputBackend(this));
@@ -165,9 +165,6 @@ void ControllerInterface::RefreshDevices(RefreshReason reason)
 #ifdef CIFACE_USE_ANDROID
   ciface::Android::PopulateDevices();
 #endif
-#ifdef CIFACE_USE_PIPES
-  ciface::Pipes::PopulateDevices();
-#endif
 
   for (auto& backend : m_input_backends)
     backend->PopulateDevices();

Source/Core/InputCommon/ControllerInterface/Pipes/Pipes.cpp

@@ -39,7 +39,19 @@ static double StringToDouble(const std::string& text)
   return result;
 }
 
-void PopulateDevices()
+class InputBackend final : public ciface::InputBackend
+{
+public:
+  using ciface::InputBackend::InputBackend;
+  void PopulateDevices() override;
+};
+
+std::unique_ptr<ciface::InputBackend> CreateInputBackend(ControllerInterface* controller_interface)
+{
+  return std::make_unique<InputBackend>(controller_interface);
+}
+
+void InputBackend::PopulateDevices()
 {
   // Search the Pipes directory for files that we can open in read-only,
   // non-blocking mode. The device name is the virtual name of the file.

Source/Core/InputCommon/ControllerInterface/Pipes/Pipes.h

@@ -21,7 +21,7 @@ namespace ciface::Pipes
 // SET {L, R} [0, 1]
 // SET {MAIN, C} [0, 1] [0, 1]
 
-void PopulateDevices();
+std::unique_ptr<ciface::InputBackend> CreateInputBackend(ControllerInterface* controller_interface);
 
 class PipeDevice : public Core::Device
 {