Line data    Source code

       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           0 :   explicit MutexLock(port::Mutex *mu) EXCLUSIVE_LOCK_FUNCTION(mu)
      26       86926 :       : mu_(mu)  {
      27       86926 :     this->mu_->Lock();
      28           0 :   }
      29       86302 :   ~MutexLock() UNLOCK_FUNCTION() { this->mu_->Unlock(); }
      30             : 
      31             :  private:
      32             :   port::Mutex *const mu_;
      33             :   // No copying allowed
      34             :   MutexLock(const MutexLock&);
      35             :   void operator=(const MutexLock&);
      36             : };
      37             : 
      38             : }  // namespace leveldb
      39             : 
      40             : 
      41             : #endif  // STORAGE_LEVELDB_UTIL_MUTEXLOCK_H_