blob: 99a913ad71808df227006ff59ed44639db0e8f87 [file] [log] [blame]
/*
* Copyright (C) 2015, 2016 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include "Timer.h"
#include <wtf/Deque.h>
#include <wtf/Function.h>
#include <wtf/WeakPtr.h>
namespace WTF {
class Lock;
};
namespace WebCore {
template <typename T>
class TaskDispatcher {
public:
explicit TaskDispatcher(T* context)
: m_context(context)
{
}
void postTask(Function<void()>&& function)
{
ASSERT(m_context);
m_context->enqueueTaskForDispatcher(WTFMove(function));
}
private:
T* m_context;
};
template<>
class TaskDispatcher<Timer> : public CanMakeWeakPtr<TaskDispatcher<Timer>> {
public:
TaskDispatcher();
void postTask(Function<void()>&&);
private:
static Timer& sharedTimer();
static WTF::Lock& sharedLock();
static void sharedTimerFired();
static Deque<WeakPtr<TaskDispatcher<Timer>>>& pendingDispatchers();
void dispatchOneTask();
Deque<Function<void()>> m_pendingTasks;
};
template <typename T>
class GenericTaskQueue : public CanMakeWeakPtr<GenericTaskQueue<T>> {
WTF_MAKE_FAST_ALLOCATED;
public:
GenericTaskQueue()
: m_dispatcher()
{
}
explicit GenericTaskQueue(T& t)
: m_dispatcher(&t)
{
}
explicit GenericTaskQueue(T* t)
: m_dispatcher(t)
, m_isClosed(!t)
{
}
typedef WTF::Function<void ()> TaskFunction;
void enqueueTask(TaskFunction&& task)
{
if (m_isClosed)
return;
++m_pendingTasks;
m_dispatcher.postTask([weakThis = makeWeakPtr(*this), task = WTFMove(task)] {
if (!weakThis)
return;
ASSERT(weakThis->m_pendingTasks);
--weakThis->m_pendingTasks;
task();
});
}
void close()
{
cancelAllTasks();
m_isClosed = true;
}
void cancelAllTasks()
{
CanMakeWeakPtr<GenericTaskQueue<T>>::weakPtrFactory().revokeAll();
m_pendingTasks = 0;
}
bool hasPendingTasks() const { return m_pendingTasks; }
bool isClosed() const { return m_isClosed; }
private:
TaskDispatcher<T> m_dispatcher;
unsigned m_pendingTasks { 0 };
bool m_isClosed { false };
};
}