xref: /aosp_15_r20/external/pigweed/pw_async2_epoll/public_overrides/pw_async2/dispatcher_native.h (revision 61c4878ac05f98d0ceed94b57d316916de578985)
1 // Copyright 2024 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 <unordered_map>
17 
18 #include "pw_assert/assert.h"
19 #include "pw_async2/dispatcher_base.h"
20 
21 namespace pw::async2::backend {
22 
23 class NativeDispatcher final : public NativeDispatcherBase {
24  public:
NativeDispatcher()25   NativeDispatcher() { PW_ASSERT_OK(NativeInit()); }
26 
27   Status NativeInit();
28 
29   enum FileDescriptorType {
30     kReadable = 1 << 0,
31     kWritable = 1 << 1,
32     kReadWrite = kReadable | kWritable,
33   };
34 
35   Status NativeRegisterFileDescriptor(int fd, FileDescriptorType type);
36   Status NativeUnregisterFileDescriptor(int fd);
37 
NativeAddReadWakerForFileDescriptor(int fd)38   Waker& NativeAddReadWakerForFileDescriptor(int fd) {
39     return wakers_[fd].read;
40   }
41 
NativeAddWriteWakerForFileDescriptor(int fd)42   Waker& NativeAddWriteWakerForFileDescriptor(int fd) {
43     return wakers_[fd].write;
44   }
45 
46  private:
47   friend class ::pw::async2::Dispatcher;
48 
49   static constexpr size_t kMaxEventsToProcessAtOnce = 5;
50 
51   struct ReadWriteWaker {
52     Waker read;
53     Waker write;
54   };
55 
56   void DoWake() final;
57   Poll<> DoRunUntilStalled(Dispatcher&, Task* task);
58   void DoRunToCompletion(Dispatcher&, Task* task);
59 
60   Status NativeWaitForWake();
61   void NativeFindAndWakeFileDescriptor(int fd, FileDescriptorType type);
62 
63   int epoll_fd_;
64   int notify_fd_;
65   int wait_fd_;
66 
67   std::unordered_map<int, ReadWriteWaker> wakers_;
68 };
69 
70 }  // namespace pw::async2::backend
71