1//===-- LockFileBase.h ------------------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#ifndef liblldb_Host_LockFileBase_h_
10#define liblldb_Host_LockFileBase_h_
11
12#include "lldb/Utility/Status.h"
13
14#include <functional>
15
16namespace lldb_private {
17
18class LockFileBase {
19public:
20  virtual ~LockFileBase() = default;
21
22  bool IsLocked() const;
23
24  Status WriteLock(const uint64_t start, const uint64_t len);
25  Status TryWriteLock(const uint64_t start, const uint64_t len);
26
27  Status ReadLock(const uint64_t start, const uint64_t len);
28  Status TryReadLock(const uint64_t start, const uint64_t len);
29
30  Status Unlock();
31
32protected:
33  using Locker = std::function<Status(const uint64_t, const uint64_t)>;
34
35  LockFileBase(int fd);
36
37  virtual bool IsValidFile() const;
38
39  virtual Status DoWriteLock(const uint64_t start, const uint64_t len) = 0;
40  virtual Status DoTryWriteLock(const uint64_t start, const uint64_t len) = 0;
41
42  virtual Status DoReadLock(const uint64_t start, const uint64_t len) = 0;
43  virtual Status DoTryReadLock(const uint64_t start, const uint64_t len) = 0;
44
45  virtual Status DoUnlock() = 0;
46
47  Status DoLock(const Locker &locker, const uint64_t start, const uint64_t len);
48
49  int m_fd; // not owned.
50  bool m_locked;
51  uint64_t m_start;
52  uint64_t m_len;
53};
54}
55
56#endif
57