//===-- RegisterCheckpoint.h ------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#ifndef LLDB_TARGET_REGISTERCHECKPOINT_H
#define LLDB_TARGET_REGISTERCHECKPOINT_H

#include "lldb/Target/StackID.h"
#include "lldb/Utility/UserID.h"
#include "lldb/lldb-private.h"

namespace lldb_private {

// Inherit from UserID in case pushing/popping all register values can be done
// using a 64 bit integer that holds a baton/cookie instead of actually having
// to read all register values into a buffer
class RegisterCheckpoint : public UserID {
public:
  enum class Reason {
    // An expression is about to be run on the thread if the protocol that
    // talks to the debuggee supports checkpointing the registers using a
    // push/pop then the UserID base class in the RegisterCheckpoint can be
    // used to store the baton/cookie that refers to the remote saved state.
    eExpression,
    // The register checkpoint wants the raw register bytes, so they must be
    // read into m_data_sp, or the save/restore checkpoint should fail.
    eDataBackup
  };

  RegisterCheckpoint(Reason reason) : UserID(0), m_reason(reason) {}

  ~RegisterCheckpoint() = default;

  lldb::WritableDataBufferSP &GetData() { return m_data_sp; }

  const lldb::WritableDataBufferSP &GetData() const { return m_data_sp; }

protected:
  lldb::WritableDataBufferSP m_data_sp;
  Reason m_reason;

  // Make RegisterCheckpointSP if you wish to share the data in this class.
  RegisterCheckpoint(const RegisterCheckpoint &) = delete;
  const RegisterCheckpoint &operator=(const RegisterCheckpoint &) = delete;
};

} // namespace lldb_private

#endif // LLDB_TARGET_REGISTERCHECKPOINT_H