[idd] clipboard: add direct synchronization

idd/LGIdd/transport/CClipboardHub.h

@@ -0,0 +1,78 @@
+/**
+ * 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 "CClipboardChannel.h"
+#include "CSRWLock.h"
+#include "transport/IClipboardSource.h"
+#include "transport/ITransport.h"
+
+class CClipboardHub final : public IClipboardTarget,
+  private IClipboardChannelHandler
+{
+private:
+  CClipboardChannel& m_channel;
+  CSRWLock            m_lifecycleLock;
+  CSRWLock            m_callbackLock;
+  CSRWLock            m_lock;
+
+  IClipboardSource * m_source          = nullptr;
+  BackendId          m_backend         = 0;
+  uint32_t           m_epoch           = 0;
+  uint64_t           m_channelEpoch    = 0;
+  uint32_t           m_generation      = 1;
+  bool               m_available       = false;
+  bool               m_active          = false;
+  bool               m_running         = false;
+  bool               m_reserved        = false;
+  bool               m_failed          = false;
+  bool               m_failurePending  = false;
+  bool               m_stopped         = false;
+
+  void AdvanceGenerationNL();
+  bool MarkFailed(IClipboardSource& source);
+  ClipboardChannelResult HoldOrDiscard(
+    const KVMFRClipboardMessage& record);
+
+  void ClipboardState(bool available, uint64_t epoch) override;
+  ClipboardChannelResult ClipboardRecord(
+    const KVMFRClipboardMessage& record,
+    const uint8_t * data) override;
+  void ClipboardReset(uint64_t epoch, uint32_t reason) override;
+
+public:
+  explicit CClipboardHub(CClipboardChannel& channel);
+  ~CClipboardHub() override;
+
+  CClipboardHub(const CClipboardHub&) = delete;
+  CClipboardHub& operator=(const CClipboardHub&) = delete;
+
+  bool Bind(BackendId backend, uint32_t epoch, IClipboardSource& source);
+  void Unbind(BackendId backend, uint32_t epoch);
+  bool TakeFailure(SourceKey& source);
+  void Stop();
+
+  ClipboardChannelResult SendClipboard(
+    const KVMFRClipboardMessage& record,
+    const uint8_t * data) override;
+  void ClipboardReceiveReady() override;
+  void ClipboardFailed() override;
+};