1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4  * License, v. 2.0. If a copy of the MPL was not distributed with this
5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 
7 #ifndef threading_LockGuard_h
8 #define threading_LockGuard_h
9 
10 #include "mozilla/Attributes.h"
11 
12 namespace js {
13 
14 template <typename Mutex>
15 class MOZ_RAII UnlockGuard;
16 
17 template <typename Mutex>
18 class MOZ_RAII LockGuard {
19   friend class UnlockGuard<Mutex>;
20   friend class ConditionVariable;
21   Mutex& lock;
22 
23  public:
LockGuard(Mutex & aLock)24   explicit LockGuard(Mutex& aLock) : lock(aLock) { lock.lock(); }
25 
~LockGuard()26   ~LockGuard() { lock.unlock(); }
27 };
28 
29 template <typename Mutex>
30 class MOZ_RAII UnlockGuard {
31   Mutex& lock;
32 
33  public:
UnlockGuard(LockGuard<Mutex> & aGuard)34   explicit UnlockGuard(LockGuard<Mutex>& aGuard) : lock(aGuard.lock) {
35     lock.unlock();
36   }
37 
~UnlockGuard()38   ~UnlockGuard() { lock.lock(); }
39 };
40 
41 }  // namespace js
42 
43 #endif  // threading_LockGuard_h
44