1 // Copyright 2022 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 "pw_chrono/system_clock.h" 17 18 namespace pw::async { 19 20 class Task; 21 22 /// Asynchronous Dispatcher abstract class. A default implementation is provided 23 /// in pw_async_basic. 24 /// 25 /// Dispatcher implements VirtualSystemClock so the Dispatcher's time can be 26 /// injected into other modules under test. This is useful for consistently 27 /// simulating time when using FakeDispatcher (rather than using 28 /// chrono::SimulatedSystemClock separately). 29 class Dispatcher : public chrono::VirtualSystemClock { 30 public: 31 ~Dispatcher() override = default; 32 33 /// Post caller owned |task|. 34 virtual void Post(Task& task) = 0; 35 36 /// Post caller owned |task| to be run after |delay|. 37 virtual void PostAfter(Task& task, chrono::SystemClock::duration delay) = 0; 38 39 /// Post caller owned |task| to be run at |time|. 40 virtual void PostAt(Task& task, chrono::SystemClock::time_point time) = 0; 41 42 /// Post caller owned |task| to be run immediately then rerun at a regular 43 /// |interval|. 44 virtual void PostPeriodic(Task& task, 45 chrono::SystemClock::duration interval) = 0; 46 /// Post caller owned |task| to be run at |time| then rerun at a regular 47 /// |interval|. |interval| must not be zero. 48 virtual void PostPeriodicAt(Task& task, 49 chrono::SystemClock::duration interval, 50 chrono::SystemClock::time_point time) = 0; 51 52 /// Returns true if |task| is succesfully canceled. 53 /// If cancelation fails, the task may be running or completed. 54 /// Periodic tasks may be posted once more after they are canceled. 55 virtual bool Cancel(Task& task) = 0; 56 }; 57 58 } // namespace pw::async 59