1 /*
2  * Copyright (c) 2024 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *     http://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,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #ifndef JS_CONCURRENT_MODULE_UTILS_LOCKS_ASYNC_LOCK_H
17 #define JS_CONCURRENT_MODULE_UTILS_LOCKS_ASYNC_LOCK_H
18 
19 #include <list>
20 #include <string>
21 #include "common.h"
22 #include "lock_request.h"
23 #include "helper/error_helper.h"
24 #include "helper/napi_helper.h"
25 #include "helper/object_helper.h"
26 
27 namespace Commonlibrary::Concurrent::LocksModule {
28 
29 struct RequestCreationInfo {
30     tid_t tid;
31     std::string creationStacktrace;
32 };
33 
34 class AsyncLock {
35 public:
36     explicit AsyncLock(const std::string &lockName);
37     explicit AsyncLock(uint32_t lockId);
38     ~AsyncLock() = default;
39 
40     napi_value LockAsync(napi_env env, napi_ref cb, LockMode mode, const LockOptions &options);
41     void CleanUpLockRequestOnCompletion(LockRequest* lockRequest);
42     bool CleanUpLockRequestOnTimeout(LockRequest* lockRequest);
43     napi_status FillLockState(napi_env env, napi_value held, napi_value pending);
44     void ProcessPendingLockRequest(napi_env env, LockRequest* syncLockRequest = nullptr);
45 
46     // Increment the reference counter
47     uint32_t IncRefCount();
48     // Decrement the reference counter.
49     // When the counter gets 0 the method deletes the instance if possible.
50     // Any way you cannot use the instance if the method returns 0.
51     uint32_t DecRefCount();
52 
53     std::vector<RequestCreationInfo> GetSatisfiedRequestInfos();
54     std::vector<RequestCreationInfo> GetPendingRequestInfos();
55 
GetLockName()56     std::string GetLockName() const
57     {
58         return lockName_;
59     }
GetLockId()60     uint32_t GetLockId() const
61     {
62         return anonymousLockId_;
63     }
64 
65 private:
66     bool CanAcquireLock(LockRequest *lockRequest);
67     napi_value CreateLockInfo(napi_env env, const LockRequest *rq);
68     void AsyncDestroy(napi_env env);
69     static void AsyncDestroyCallback(napi_env env, napi_status status, void *data);
70     template <bool isAsync>
71     void ProcessLockRequest(napi_env env, LockRequest *lockRequest);
72     void ProcessPendingLockRequestUnsafe(napi_env env, LockRequest* syncLockRequest = nullptr);
73 
74     std::list<LockRequest *> pendingList_ {};
75     std::list<LockRequest *> heldList_ {};
76     LockMode lockStatus_ = LOCK_MODE_UNLOCK;
77     std::string lockName_ = "";    // "" for anonymous lock
78     uint32_t anonymousLockId_ {};  // 0 for Non-anonymous lock
79     std::mutex asyncLockMutex_;
80     uint32_t refCount_ = 1;
81 };
82 
83 }  // namespace Commonlibrary::Concurrent::LocksModule
84 #endif  // JS_CONCURRENT_MODULE_UTILS_LOCKS_ASYNC_LOCK_H
85