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 | |
11 | namespace 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 | |
23 | class 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 | |