1 /*
2  * Copyright (c) 2023 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 PLUGIN_MANAGER_H
17 #define PLUGIN_MANAGER_H
18 
19 #include <memory>
20 #include <mutex>
21 
22 #include <dlfcn.h>
23 
24 #include "nocopyable.h"
25 
26 #include "i_context.h"
27 #include "i_plugin_manager.h"
28 
29 namespace OHOS {
30 namespace Msdp {
31 namespace DeviceStatus {
32 
33 // Loading、unloading and bookkeeping of modules.
34 class PluginManager final : public IPluginManager {
35     template<typename IPlugin>
36     class Plugin final {
37     public:
38         Plugin(IContext *context, void *handle);
39         ~Plugin();
40         DISALLOW_COPY_AND_MOVE(Plugin);
41 
42         IPlugin* GetInstance();
43 
44     private:
45         IContext *context_ { nullptr };
46         void *handle_ { nullptr };
47         IPlugin *instance_ { nullptr };
48     };
49 
50     template<typename IPlugin>
51     using CreatePlugin = IPlugin* (*)(IContext *context);
52 
53     template<typename IPlugin>
54     using DestroyPlugin = void (*)(IPlugin *);
55 
56 public:
PluginManager(IContext * context)57     PluginManager(IContext *context) : context_(context) {}
58     ~PluginManager() = default;
59     DISALLOW_COPY_AND_MOVE(PluginManager);
60 
61     ICooperate* LoadCooperate() override;
62     void UnloadCooperate() override;
63 
64     IMotionDrag* LoadMotionDrag() override;
65     void UnloadMotionDrag() override;
66 
67 private:
68     template<typename IPlugin>
69     std::unique_ptr<Plugin<IPlugin>> LoadLibrary(IContext *context, const char *libPath);
70 
71 private:
72     std::mutex lock_;
73     IContext *context_ { nullptr };
74     std::unique_ptr<Plugin<ICooperate>> cooperate_ { nullptr };
75     std::unique_ptr<Plugin<IMotionDrag>> motionDrag_ { nullptr };
76 };
77 
78 template<typename IPlugin>
Plugin(IContext * context,void * handle)79 PluginManager::Plugin<IPlugin>::Plugin(IContext *context, void *handle)
80     : context_(context), handle_(handle)
81 {}
82 
83 template<typename IPlugin>
~Plugin()84 PluginManager::Plugin<IPlugin>::~Plugin()
85 {
86     if (instance_ != nullptr) {
87         DestroyPlugin<IPlugin> destroy =
88             reinterpret_cast<DestroyPlugin<IPlugin>>(::dlsym(handle_, "DestroyInstance"));
89         if (destroy != nullptr) {
90             destroy(instance_);
91         }
92     }
93     ::dlclose(handle_);
94 }
95 
96 template<typename IPlugin>
GetInstance()97 IPlugin* PluginManager::Plugin<IPlugin>::GetInstance()
98 {
99     if (instance_ != nullptr) {
100         return instance_;
101     }
102     CreatePlugin<IPlugin> create = reinterpret_cast<CreatePlugin<IPlugin>>(::dlsym(handle_, "CreateInstance"));
103     if (create != nullptr) {
104         instance_ = create(context_);
105     }
106     return instance_;
107 }
108 
109 template<typename IPlugin>
LoadLibrary(IContext * context,const char * libPath)110 std::unique_ptr<PluginManager::Plugin<IPlugin>> PluginManager::LoadLibrary(IContext *context, const char *libPath)
111 {
112     char realPath[PATH_MAX] = { 0 };
113     if (realpath(libPath, realPath) == nullptr) {
114         FI_HILOGE("Path is error, path is %{private}s", libPath);
115         return nullptr;
116     }
117     void *handle = ::dlopen(libPath, RTLD_NOW);
118     return (handle != nullptr ? std::make_unique<Plugin<IPlugin>>(context, handle) : nullptr);
119 }
120 } // namespace DeviceStatus
121 } // namespace Msdp
122 } // namespace OHOS
123 #endif // PLUGIN_MANAGER_H