[idd] transport: isolate interactive services

idd/LGIdd/transport/IControlSink.h

@@ -0,0 +1,69 @@
+/**
+ * Looking Glass
+ * Copyright © 2017-2026 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#pragma once
+
+#include "postprocess/D12FrameFormat.h"
+
+#include <Windows.h>
+#include <wdf.h>
+#include <IddCx.h>
+
+#include <memory>
+#include <stddef.h>
+#include <stdint.h>
+
+struct ControlToken
+{
+  uint32_t backend = 0;
+  uint32_t epoch   = 0;
+};
+
+enum class ControlResult
+{
+  APPLIED,
+  RETRY,
+  FAILED,
+};
+
+class IControlEvents
+{
+public:
+  virtual ~IControlEvents() = default;
+
+  virtual void OnControlReplay(const ControlToken& token) = 0;
+};
+
+class IControlSink
+{
+public:
+  virtual ~IControlSink() = default;
+
+  // Passing nullptr is a callback-quiescence barrier. Once this returns, no
+  // callback using the previous events pointer may still be running.
+  virtual void SetControlEvents(
+    IControlEvents * events, const ControlToken& token) = 0;
+
+  // These calls perform at most one delivery attempt.
+  virtual ControlResult SendCursor(const IDARG_OUT_QUERY_HWCURSOR& info,
+    const BYTE * data, size_t size, UINT sdrWhiteLevel) = 0;
+  virtual ControlResult SetColorTransform(
+    std::shared_ptr<const D12ColorTransform> transform) = 0;
+};