blob: 9fec948b86a56ec27996e8ad7de75c2bbe8395f6 [file] [log] [blame]
// Copyright 2019 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <map>
#include <memory>
#include <queue>
#include "include/libplatform/libplatform-export.h"
#include "src/base/macros.h"
#include "src/base/platform/condition-variable.h"
#include "src/base/platform/mutex.h"
namespace v8 {
class Task;
namespace platform {
// DelayedTaskQueue provides queueing for immediate and delayed tasks. It does
// not provide any guarantees about ordering of tasks, except that immediate
// tasks will be run in the order that they are posted.
class V8_PLATFORM_EXPORT DelayedTaskQueue {
using TimeFunction = double (*)();
explicit DelayedTaskQueue(TimeFunction time_function);
double MonotonicallyIncreasingTime();
// Appends an immediate task to the queue. The queue takes ownership of
// |task|. Tasks appended via this method will be run in order. Thread-safe.
void Append(std::unique_ptr<Task> task);
// Appends a delayed task to the queue. There is no ordering guarantee
// provided regarding delayed tasks, both with respect to other delayed tasks
// and non-delayed tasks that were appended using Append(). Thread-safe.
void AppendDelayed(std::unique_ptr<Task> task, double delay_in_seconds);
// Returns the next task to process. Blocks if no task is available.
// Returns nullptr if the queue is terminated. Will return either an immediate
// task posted using Append() or a delayed task where the deadline has passed,
// according to the |time_function| provided in the constructor. Thread-safe.
std::unique_ptr<Task> GetNext();
// Terminate the queue.
void Terminate();
std::unique_ptr<Task> PopTaskFromDelayedQueue(double now);
base::ConditionVariable queues_condition_var_;
base::Mutex lock_;
std::queue<std::unique_ptr<Task>> task_queue_;
std::multimap<double, std::unique_ptr<Task>> delayed_task_queue_;
bool terminated_ = false;
TimeFunction time_function_;
} // namespace platform
} // namespace v8