1 /*
2  * Copyright (c) 2021-2022 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 BASE_EVENTHANDLER_FRAMEWORKS_EVENTHANDLER_INCLUDE_EPOLL_IO_WAITER_H
17 #define BASE_EVENTHANDLER_FRAMEWORKS_EVENTHANDLER_INCLUDE_EPOLL_IO_WAITER_H
18 
19 #include <atomic>
20 #include <mutex>
21 
22 #include "io_waiter.h"
23 #include "nocopyable.h"
24 
25 #include <map>
26 #include <uv.h>
27 
28 namespace OHOS {
29 namespace AppExecFwk {
30 // Use epoll to listen file descriptor.
31 class EpollIoWaiter final : public IoWaiter {
32 public:
33     EpollIoWaiter() = default;
34     ~EpollIoWaiter() final;
35     DISALLOW_COPY_AND_MOVE(EpollIoWaiter);
36 
37     /**
38      * Initialize epoll.
39      *
40      * @return True if succeeded.
41      */
42     bool Init();
43 
44     bool WaitFor(std::unique_lock<std::mutex> &lock, int64_t nanoseconds) final;
45 
46     void NotifyOne() final;
47     void NotifyAll() final;
48 
49     bool SupportListeningFileDescriptor() const final;
50 
51     bool AddFileDescriptor(int32_t fd, uint32_t events) final;
52     void RemoveFileDescriptor(int32_t fd) final;
53 
54     void SetFileDescriptorEventCallback(const FileDescriptorEventCallback &callback) final;
55 
56 private:
57     static void OnPoll(uv_poll_t *poll, int status, int events);
58     static void OnTimer(uv_timer_t *timer);
59     static void OnSignal(uv_signal_t *signal, int32_t signum);
60     template<typename T>
GetInstance(T * that)61     static EpollIoWaiter &GetInstance(T *that)
62     {
63         return *reinterpret_cast<EpollIoWaiter *>(that->data);
64     }
65 
66     uv_loop_t loop_ = {.data = this};
67     uv_signal_t signal_ = {.data = this};
68     uv_timer_t timer_ = {.data = this};
69     std::mutex timerMutex_;
70     std::map<int32_t, uv_poll_t> pollMap_;
71     bool overtime = false;
72     FileDescriptorEventCallback fdcallback_ = nullptr;
73 };
74 }  // namespace AppExecFwk
75 }  // namespace OHOS
76 
77 #endif  // #ifndef BASE_EVENTHANDLER_FRAMEWORKS_EVENTHANDLER_INCLUDE_EPOLL_IO_WAITER_H
78