1 /* 2 * Copyright (c) Facebook, Inc. and its affiliates. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #pragma once 18 19 #include <atomic> 20 21 #include <glog/logging.h> 22 23 #include <folly/executors/ScheduledExecutor.h> 24 #include <folly/futures/Future.h> 25 26 namespace folly { 27 28 struct FOLLY_EXPORT TimekeeperScheduledExecutorNoTimekeeper 29 : public std::logic_error { TimekeeperScheduledExecutorNoTimekeeperTimekeeperScheduledExecutorNoTimekeeper30 TimekeeperScheduledExecutorNoTimekeeper() 31 : std::logic_error("No Timekeeper available") {} 32 }; 33 34 // This class turns a Executor into a ScheduledExecutor. 35 class TimekeeperScheduledExecutor : public ScheduledExecutor { 36 public: 37 TimekeeperScheduledExecutor(TimekeeperScheduledExecutor const&) = delete; 38 TimekeeperScheduledExecutor& operator=(TimekeeperScheduledExecutor const&) = 39 delete; 40 TimekeeperScheduledExecutor(TimekeeperScheduledExecutor&&) = delete; 41 TimekeeperScheduledExecutor& operator=(TimekeeperScheduledExecutor&&) = 42 delete; 43 44 static Executor::KeepAlive<TimekeeperScheduledExecutor> create( 45 Executor::KeepAlive<> parent, 46 Function<std::shared_ptr<Timekeeper>()> getTimekeeper = 47 detail::getTimekeeperSingleton); 48 49 virtual void add(Func func) override; 50 51 virtual void scheduleAt( 52 Func&& func, ScheduledExecutor::TimePoint const& t) override; 53 54 protected: 55 bool keepAliveAcquire() noexcept override; 56 void keepAliveRelease() noexcept override; 57 58 private: TimekeeperScheduledExecutor(KeepAlive<Executor> && parent,Function<std::shared_ptr<Timekeeper> ()> getTimekeeper)59 TimekeeperScheduledExecutor( 60 KeepAlive<Executor>&& parent, 61 Function<std::shared_ptr<Timekeeper>()> getTimekeeper) 62 : parent_(std::move(parent)), getTimekeeper_(std::move(getTimekeeper)) {} 63 ~TimekeeperScheduledExecutor()64 ~TimekeeperScheduledExecutor() { DCHECK(!keepAliveCounter_); } 65 66 void run(Func); 67 68 KeepAlive<Executor> parent_; 69 Function<std::shared_ptr<Timekeeper>()> getTimekeeper_; 70 std::atomic<ssize_t> keepAliveCounter_{1}; 71 }; 72 73 } // namespace folly 74