xref: /aosp_15_r20/external/pigweed/pw_rpc/public/pw_rpc/internal/lock.h (revision 61c4878ac05f98d0ceed94b57d316916de578985)
1 // Copyright 2021 The Pigweed Authors
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License"); you may not
4 // use this file except in compliance with the License. You may obtain a copy of
5 // the License at
6 //
7 //     https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
11 // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
12 // License for the specific language governing permissions and limitations under
13 // the License.
14 #pragma once
15 
16 #include "pw_rpc/internal/config.h"
17 #include "pw_sync/lock_annotations.h"
18 #include "pw_toolchain/no_destructor.h"
19 
20 #if PW_RPC_USE_GLOBAL_MUTEX
21 
22 #include "pw_sync/mutex.h"  // nogncheck
23 
24 #endif  // PW_RPC_USE_GLOBAL_MUTEX
25 
26 namespace pw::rpc::internal {
27 
28 #if PW_RPC_USE_GLOBAL_MUTEX
29 
30 using RpcLock = sync::Mutex;
31 
32 #else
33 
34 class PW_LOCKABLE("pw::rpc::internal::RpcLock") RpcLock {
35  public:
36   constexpr void lock() PW_EXCLUSIVE_LOCK_FUNCTION() {}
37   constexpr void unlock() PW_UNLOCK_FUNCTION() {}
38 };
39 
40 #endif  // PW_RPC_USE_GLOBAL_MUTEX
41 
rpc_lock()42 inline RpcLock& rpc_lock() {
43   static NoDestructor<RpcLock> lock;
44   return *lock;
45 }
46 
47 class PW_SCOPED_LOCKABLE
RpcLockGuard()48 RpcLockGuard{public : RpcLockGuard()
49                  PW_EXCLUSIVE_LOCK_FUNCTION(rpc_lock()){rpc_lock().lock();
50 }  // namespace pw::rpc::internal
51 
52 ~RpcLockGuard() PW_UNLOCK_FUNCTION(rpc_lock()) { rpc_lock().unlock(); }
53 }
54 ;
55 
56 // Releases the RPC lock, yields, and reacquires it.
57 void YieldRpcLock() PW_EXCLUSIVE_LOCKS_REQUIRED(rpc_lock());
58 
59 }  // namespace pw::rpc::internal
60