xref: /aosp_15_r20/frameworks/native/include/ftl/shared_mutex.h (revision 38e8c45f13ce32b0dcecb25141ffecaf386fa17f)
1*38e8c45fSAndroid Build Coastguard Worker /*
2*38e8c45fSAndroid Build Coastguard Worker  * Copyright 2022 The Android Open Source Project
3*38e8c45fSAndroid Build Coastguard Worker  *
4*38e8c45fSAndroid Build Coastguard Worker  * Licensed under the Apache License, Version 2.0 (the "License");
5*38e8c45fSAndroid Build Coastguard Worker  * you may not use this file except in compliance with the License.
6*38e8c45fSAndroid Build Coastguard Worker  * You may obtain a copy of the License at
7*38e8c45fSAndroid Build Coastguard Worker  *
8*38e8c45fSAndroid Build Coastguard Worker  *      http://www.apache.org/licenses/LICENSE-2.0
9*38e8c45fSAndroid Build Coastguard Worker  *
10*38e8c45fSAndroid Build Coastguard Worker  * Unless required by applicable law or agreed to in writing, software
11*38e8c45fSAndroid Build Coastguard Worker  * distributed under the License is distributed on an "AS IS" BASIS,
12*38e8c45fSAndroid Build Coastguard Worker  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13*38e8c45fSAndroid Build Coastguard Worker  * See the License for the specific language governing permissions and
14*38e8c45fSAndroid Build Coastguard Worker  * limitations under the License.
15*38e8c45fSAndroid Build Coastguard Worker  */
16*38e8c45fSAndroid Build Coastguard Worker 
17*38e8c45fSAndroid Build Coastguard Worker #pragma once
18*38e8c45fSAndroid Build Coastguard Worker 
19*38e8c45fSAndroid Build Coastguard Worker #include <shared_mutex>
20*38e8c45fSAndroid Build Coastguard Worker 
21*38e8c45fSAndroid Build Coastguard Worker namespace android::ftl {
22*38e8c45fSAndroid Build Coastguard Worker 
23*38e8c45fSAndroid Build Coastguard Worker // Wrapper around std::shared_mutex to provide capabilities for thread-safety
24*38e8c45fSAndroid Build Coastguard Worker // annotations.
25*38e8c45fSAndroid Build Coastguard Worker // TODO(b/257958323): This class is no longer needed once b/135688034 is fixed (currently blocked on
26*38e8c45fSAndroid Build Coastguard Worker // b/175635923).
27*38e8c45fSAndroid Build Coastguard Worker class [[clang::capability("shared_mutex")]] SharedMutex final {
28*38e8c45fSAndroid Build Coastguard Worker  public:
lock()29*38e8c45fSAndroid Build Coastguard Worker   [[clang::acquire_capability()]] void lock() {
30*38e8c45fSAndroid Build Coastguard Worker     mutex_.lock();
31*38e8c45fSAndroid Build Coastguard Worker   }
unlock()32*38e8c45fSAndroid Build Coastguard Worker   [[clang::release_capability()]] void unlock() {
33*38e8c45fSAndroid Build Coastguard Worker     mutex_.unlock();
34*38e8c45fSAndroid Build Coastguard Worker   }
35*38e8c45fSAndroid Build Coastguard Worker 
lock_shared()36*38e8c45fSAndroid Build Coastguard Worker   [[clang::acquire_shared_capability()]] void lock_shared() {
37*38e8c45fSAndroid Build Coastguard Worker     mutex_.lock_shared();
38*38e8c45fSAndroid Build Coastguard Worker   }
unlock_shared()39*38e8c45fSAndroid Build Coastguard Worker   [[clang::release_shared_capability()]] void unlock_shared() {
40*38e8c45fSAndroid Build Coastguard Worker     mutex_.unlock_shared();
41*38e8c45fSAndroid Build Coastguard Worker   }
42*38e8c45fSAndroid Build Coastguard Worker 
43*38e8c45fSAndroid Build Coastguard Worker  private:
44*38e8c45fSAndroid Build Coastguard Worker   std::shared_mutex mutex_;
45*38e8c45fSAndroid Build Coastguard Worker };
46*38e8c45fSAndroid Build Coastguard Worker 
47*38e8c45fSAndroid Build Coastguard Worker }  // namespace android::ftl
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