ControllerInterface: enable hotplugging on macOS

Source/Core/InputCommon/ControllerInterface/OSX/RunLoopStopper.h

@@ -0,0 +1,45 @@
+// Copyright 2016 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <Foundation/Foundation.h>
+
+namespace ciface
+{
+namespace OSX
+{
+class RunLoopStopper
+{
+  CFRunLoopSourceRef m_source;
+  CFRunLoopRef m_runloop = nullptr;
+
+public:
+  RunLoopStopper()
+  {
+    CFRunLoopSourceContext ctx = {.version = 0,
+                                  .perform = [](void*) { CFRunLoopStop(CFRunLoopGetCurrent()); }};
+    m_source = CFRunLoopSourceCreate(kCFAllocatorDefault, 0, &ctx);
+  }
+  ~RunLoopStopper() { CFRelease(m_source); }
+  void Signal()
+  {
+    CFRunLoopSourceSignal(m_source);
+    if (m_runloop != nullptr)
+      CFRunLoopWakeUp(m_runloop);
+  }
+  void AddToRunLoop(CFRunLoopRef runloop, CFStringRef mode)
+  {
+    m_runloop = runloop;
+    CFRunLoopAddSource(runloop, m_source, mode);
+  }
+  void RemoveFromRunLoop(CFRunLoopRef runloop, CFStringRef mode)
+  {
+    m_runloop = nullptr;
+    CFRunLoopRemoveSource(runloop, m_source, mode);
+  }
+};
+
+}  // namespace ciface
+}  // namespace OSX