1 #pragma once 2 3 /* 4 * Copyright (C) 2017 The Android Open Source Project 5 * 6 * Licensed under the Apache License, Version 2.0 (the "License"); 7 * you may not use this file except in compliance with the License. 8 * You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 19 #include "common/vsoc/shm/lock.h" 20 21 namespace vsoc { 22 23 class RegionView; 24 25 /* 26 * Implements std::lock_guard like functionality for the vsoc locks. 27 */ 28 29 template <typename Lock> 30 class LockGuard { 31 public: LockGuard(Lock * lock)32 explicit LockGuard(Lock* lock) : lock_(lock) { 33 lock_->Lock(); 34 } 35 LockGuard(LockGuard && o)36 LockGuard(LockGuard&& o) noexcept { 37 lock_ = o.lock_; 38 o.lock_ = nullptr; 39 } 40 41 LockGuard(const LockGuard&) = delete; 42 LockGuard& operator=(const LockGuard&) = delete; 43 ~LockGuard()44 ~LockGuard() { 45 if (lock_) { 46 lock_->Unlock(); 47 } 48 } 49 50 private: 51 Lock* lock_; 52 }; 53 54 template <> 55 class LockGuard<::vsoc::layout::GuestAndHostLock> { 56 using Lock = ::vsoc::layout::GuestAndHostLock; 57 58 public: LockGuard(Lock * lock,RegionView * region)59 LockGuard(Lock* lock, RegionView* region) : lock_(lock), region_(region) { 60 lock_->Lock(region_); 61 } 62 LockGuard(LockGuard && o)63 LockGuard(LockGuard&& o) noexcept { 64 lock_ = o.lock_; 65 o.lock_ = nullptr; 66 region_ = o.region_; 67 o.region_ = nullptr; 68 } 69 70 LockGuard(const LockGuard&) = delete; 71 LockGuard& operator=(const LockGuard&) = delete; 72 ~LockGuard()73 ~LockGuard() { 74 if (lock_) { 75 lock_->Unlock(region_); 76 } 77 } 78 79 private: 80 Lock* lock_; 81 RegionView* region_; 82 }; 83 84 } // namespace vsoc 85