webrtc/rtc_base/task_utils/to_queued_task.h
Tommi a98cea863d Remove the PendingTaskSafetyFlag::Pointer type add ScopedTaskSafety.
ScopedTaskSafety simplifies usage of PendingTaskSafetyFlag,
so this CL also includes ToQueuedTask support for ScopedTaskSafety
and test updates.

This is following up on feedback in the following CL:
https://webrtc-review.googlesource.com/c/src/+/174262

Change-Id: Idd38dfc1914b24a05fdc4ad256b409dcf1795fc0
Bug: none
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/174740
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Commit-Queue: Tommi <tommi@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31241}
2020-05-13 14:17:39 +00:00

111 lines
3.7 KiB
C++

/*
* Copyright 2019 The WebRTC 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 in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef RTC_BASE_TASK_UTILS_TO_QUEUED_TASK_H_
#define RTC_BASE_TASK_UTILS_TO_QUEUED_TASK_H_
#include <memory>
#include <type_traits>
#include <utility>
#include "api/task_queue/queued_task.h"
#include "rtc_base/task_utils/pending_task_safety_flag.h"
namespace webrtc {
namespace webrtc_new_closure_impl {
// Simple implementation of QueuedTask for use with rtc::Bind and lambdas.
template <typename Closure>
class ClosureTask : public QueuedTask {
public:
explicit ClosureTask(Closure&& closure)
: closure_(std::forward<Closure>(closure)) {}
private:
bool Run() override {
closure_();
return true;
}
typename std::decay<Closure>::type closure_;
};
template <typename Closure>
class SafetyClosureTask : public QueuedTask {
public:
explicit SafetyClosureTask(rtc::scoped_refptr<PendingTaskSafetyFlag> safety,
Closure&& closure)
: closure_(std::forward<Closure>(closure)),
safety_flag_(std::move(safety)) {}
private:
bool Run() override {
if (safety_flag_->alive())
closure_();
return true;
}
typename std::decay<Closure>::type closure_;
rtc::scoped_refptr<PendingTaskSafetyFlag> safety_flag_;
};
// Extends ClosureTask to also allow specifying cleanup code.
// This is useful when using lambdas if guaranteeing cleanup, even if a task
// was dropped (queue is too full), is required.
template <typename Closure, typename Cleanup>
class ClosureTaskWithCleanup : public ClosureTask<Closure> {
public:
ClosureTaskWithCleanup(Closure&& closure, Cleanup&& cleanup)
: ClosureTask<Closure>(std::forward<Closure>(closure)),
cleanup_(std::forward<Cleanup>(cleanup)) {}
~ClosureTaskWithCleanup() override { cleanup_(); }
private:
typename std::decay<Cleanup>::type cleanup_;
};
} // namespace webrtc_new_closure_impl
// Convenience function to construct closures that can be passed directly
// to methods that support std::unique_ptr<QueuedTask> but not template
// based parameters.
template <typename Closure>
std::unique_ptr<QueuedTask> ToQueuedTask(Closure&& closure) {
return std::make_unique<webrtc_new_closure_impl::ClosureTask<Closure>>(
std::forward<Closure>(closure));
}
template <typename Closure>
std::unique_ptr<QueuedTask> ToQueuedTask(
rtc::scoped_refptr<PendingTaskSafetyFlag> safety,
Closure&& closure) {
return std::make_unique<webrtc_new_closure_impl::SafetyClosureTask<Closure>>(
std::move(safety), std::forward<Closure>(closure));
}
template <typename Closure>
std::unique_ptr<QueuedTask> ToQueuedTask(const ScopedTaskSafety& safety,
Closure&& closure) {
return ToQueuedTask(safety.flag(), std::forward<Closure>(closure));
}
template <typename Closure,
typename Cleanup,
typename std::enable_if<!std::is_same<
typename std::remove_const<
typename std::remove_reference<Closure>::type>::type,
ScopedTaskSafety>::value>::type* = nullptr>
std::unique_ptr<QueuedTask> ToQueuedTask(Closure&& closure, Cleanup&& cleanup) {
return std::make_unique<
webrtc_new_closure_impl::ClosureTaskWithCleanup<Closure, Cleanup>>(
std::forward<Closure>(closure), std::forward<Cleanup>(cleanup));
}
} // namespace webrtc
#endif // RTC_BASE_TASK_UTILS_TO_QUEUED_TASK_H_