//===-- LockFileBase.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_HOST_LOCKFILEBASE_H

#define LLDB_HOST_LOCKFILEBASE_H

#include "lldb/Utility/Status.h"

#include <functional>

namespace lldb_private {

class LockFileBase {

public:

  virtual ~LockFileBase() = default;

  bool IsLocked() const;

  Status WriteLock(const uint64_t start, const uint64_t len);

  Status TryWriteLock(const uint64_t start, const uint64_t len);

  Status ReadLock(const uint64_t start, const uint64_t len);

  Status TryReadLock(const uint64_t start, const uint64_t len);

  Status Unlock();

protected:

  using Locker = std::function<Status(const uint64_t, const uint64_t)>;

  LockFileBase(int fd);

  virtual bool IsValidFile() const;

  virtual Status DoWriteLock(const uint64_t start, const uint64_t len) = 0;

  virtual Status DoTryWriteLock(const uint64_t start, const uint64_t len) = 0;

  virtual Status DoReadLock(const uint64_t start, const uint64_t len) = 0;

  virtual Status DoTryReadLock(const uint64_t start, const uint64_t len) = 0;

  virtual Status DoUnlock() = 0;

  Status DoLock(const Locker &locker, const uint64_t start, const uint64_t len);

  int m_fd; // not owned.

  bool m_locked;

  uint64_t m_start;

  uint64_t m_len;

};

}

#endif