1// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file. See the AUTHORS file for names of contributors.
4
5#ifndef STORAGE_LEVELDB_UTIL_MUTEXLOCK_H_
6#define STORAGE_LEVELDB_UTIL_MUTEXLOCK_H_
7
8#include "port/port.h"
9#include "port/thread_annotations.h"
10
11namespace leveldb {
12
13// Helper class that locks a mutex on construction and unlocks the mutex when
14// the destructor of the MutexLock object is invoked.
15//
16// Typical usage:
17//
18// void MyClass::MyMethod() {
19// MutexLock l(&mu_); // mu_ is an instance variable
20// ... some complex code, possibly with multiple return paths ...
21// }
22
23class SCOPED_LOCKABLE MutexLock {
24 public:
25 explicit MutexLock(port::Mutex* mu) EXCLUSIVE_LOCK_FUNCTION(mu) : mu_(mu) {
26 this->mu_->Lock();
27 }
28 ~MutexLock() UNLOCK_FUNCTION() { this->mu_->Unlock(); }
29
30 MutexLock(const MutexLock&) = delete;
31 MutexLock& operator=(const MutexLock&) = delete;
32
33 private:
34 port::Mutex* const mu_;
35};
36
37} // namespace leveldb
38
39#endif // STORAGE_LEVELDB_UTIL_MUTEXLOCK_H_
40