1 /*
2 * Copyright (C) 2021 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 OHOS_IPC_IREMOTE_BROKER_H
17 #define OHOS_IPC_IREMOTE_BROKER_H
18
19 #include <unordered_map>
20 #include <functional>
21 #include "iremote_object.h"
22 #include "refbase.h"
23
24 namespace OHOS {
25 template <typename T> class BrokerCreator {
26 public:
27 BrokerCreator() = default;
28 ~BrokerCreator() = default;
operator()29 sptr<IRemoteBroker> operator () (const sptr<IRemoteObject> &object)
30 {
31 T *proxy = new (std::nothrow) T(object);
32 if (proxy != nullptr) {
33 return static_cast<IRemoteBroker *>(proxy);
34 }
35 return nullptr;
36 };
37 };
38
39 class IRemoteBroker : public virtual RefBase {
40 public:
41 IRemoteBroker() = default;
42 virtual ~IRemoteBroker() override = default;
43 virtual sptr<IRemoteObject> AsObject() = 0;
AsImplement(const sptr<IRemoteObject> & object)44 static inline sptr<IRemoteBroker> AsImplement(const sptr<IRemoteObject> &object)
45 {
46 return nullptr;
47 }
48 };
49
50 #define DECLARE_INTERFACE_DESCRIPTOR(DESCRIPTOR) \
51 static inline const std::u16string metaDescriptor_ = { DESCRIPTOR }; \
52 static inline const std::u16string &GetDescriptor() \
53 { \
54 return metaDescriptor_; \
55 }
56
57 class BrokerRegistration {
58 using Constructor = std::function<sptr<IRemoteBroker>(const sptr<IRemoteObject> &object)>;
59
60 public:
61 static BrokerRegistration &Get();
62 bool Register(const std::u16string &descriptor, const Constructor &creator);
63 void Unregister(const std::u16string &descriptor);
64 sptr<IRemoteBroker> NewInstance(const std::u16string &descriptor, const sptr<IRemoteObject> &object);
65
66 protected:
67 BrokerRegistration() = default;
68 ~BrokerRegistration();
69
70 private:
71 BrokerRegistration(const BrokerRegistration &) = delete;
72 BrokerRegistration(BrokerRegistration &&) = delete;
73 BrokerRegistration &operator = (const BrokerRegistration &) = delete;
74 BrokerRegistration &operator = (BrokerRegistration &&) = delete;
75 std::mutex creatorMutex_;
76 std::unordered_map<std::u16string, Constructor> creators_;
77 };
78
79 template <typename T> class BrokerDelegator {
80 public:
81 BrokerDelegator();
82 ~BrokerDelegator();
83
84 private:
85 BrokerDelegator(const BrokerDelegator &) = delete;
86 BrokerDelegator(BrokerDelegator &&) = delete;
87 BrokerDelegator &operator = (const BrokerDelegator &) = delete;
88 BrokerDelegator &operator = (BrokerDelegator &&) = delete;
89 };
90
BrokerDelegator()91 template <typename T> BrokerDelegator<T>::BrokerDelegator()
92 {
93 const std::u16string descriptor = T::GetDescriptor();
94 BrokerRegistration ®istration = BrokerRegistration::Get();
95 registration.Register(descriptor, BrokerCreator<T>());
96 }
97
~BrokerDelegator()98 template <typename T> BrokerDelegator<T>::~BrokerDelegator()
99 {
100 const std::u16string descriptor = T::GetDescriptor();
101 BrokerRegistration ®istration = BrokerRegistration::Get();
102 registration.Unregister(descriptor);
103 }
104
iface_cast(const sptr<IRemoteObject> & object)105 template <typename INTERFACE> inline sptr<INTERFACE> iface_cast(const sptr<IRemoteObject> &object)
106 {
107 const std::u16string descriptor = INTERFACE::GetDescriptor();
108 BrokerRegistration ®istration = BrokerRegistration::Get();
109 sptr<IRemoteBroker> broker = registration.NewInstance(descriptor, object);
110 return static_cast<INTERFACE *>(broker.GetRefPtr());
111 }
112 } // namespace OHOS
113 #endif // OHOS_IPC_IREMOTE_BROKER_H
114