mirror of
https://gitlab.winehq.org/wine/wine-gecko.git
synced 2024-09-13 09:24:08 -07:00
97 lines
2.9 KiB
C++
97 lines
2.9 KiB
C++
/* -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 2; -*- */
|
|
/* vim: set sw=4 ts=8 et tw=80 : */
|
|
/* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
#ifndef mozilla_dom_TaskThrottler_h
|
|
#define mozilla_dom_TaskThrottler_h
|
|
|
|
#include "nsAutoPtr.h"
|
|
#include "nsTArray.h"
|
|
#include "mozilla/TimeStamp.h"
|
|
|
|
class CancelableTask;
|
|
namespace tracked_objects {
|
|
class Location;
|
|
}
|
|
|
|
namespace mozilla {
|
|
namespace layers {
|
|
|
|
/** The TaskThrottler prevents update event overruns. It is used in cases where
|
|
* you're sending an async message and waiting for a reply. You need to call
|
|
* PostTask to queue a task and TaskComplete when you get a response.
|
|
*
|
|
* The call to TaskComplete will run the recent task posted since the last
|
|
* request was sent, if any. This means that at any time there can be at most 1
|
|
* outstanding request being processed and at most 1 queued behind it.
|
|
*
|
|
* This is used in the context of repainting a scrollable region. While another
|
|
* process is painting you might get several updates from the UI thread but when
|
|
* the paint is complete you want to send the most recent.
|
|
*/
|
|
|
|
class TaskThrottler {
|
|
public:
|
|
TaskThrottler(const TimeStamp& aTimeStamp);
|
|
|
|
/** Post a task to be run as soon as there are no outstanding tasks.
|
|
*
|
|
* @param aLocation Use the macro FROM_HERE
|
|
* @param aTask Ownership of this object is transferred to TaskThrottler
|
|
* which will delete it when it is either run or becomes
|
|
* obsolete or the TaskThrottler is destructed.
|
|
*/
|
|
void PostTask(const tracked_objects::Location& aLocation,
|
|
CancelableTask* aTask, const TimeStamp& aTimeStamp);
|
|
/**
|
|
* Mark the task as complete and process the next queued task.
|
|
*/
|
|
void TaskComplete(const TimeStamp& aTimeStamp);
|
|
|
|
/**
|
|
* Calculate the average time between processing the posted task and getting
|
|
* the TaskComplete() call back.
|
|
*/
|
|
TimeDuration AverageDuration();
|
|
|
|
/**
|
|
* return true if Throttler has an outstanding task
|
|
*/
|
|
bool IsOutstanding() { return mOutstanding; }
|
|
|
|
/**
|
|
* Return the time elapsed since the last request was processed
|
|
*/
|
|
TimeDuration TimeSinceLastRequest(const TimeStamp& aTimeStamp);
|
|
|
|
/**
|
|
* Clear average history.
|
|
*/
|
|
void ClearHistory() { mDurations.Clear(); }
|
|
|
|
/**
|
|
* @param aMaxDurations The maximum number of durations to measure.
|
|
*/
|
|
|
|
void SetMaxDurations(uint32_t aMaxDurations)
|
|
{
|
|
mMaxDurations = aMaxDurations;
|
|
}
|
|
|
|
private:
|
|
bool mOutstanding;
|
|
nsAutoPtr<CancelableTask> mQueuedTask;
|
|
TimeStamp mStartTime;
|
|
|
|
// How long it took in the past to paint after a series of previous requests.
|
|
nsTArray<TimeDuration> mDurations;
|
|
uint32_t mMaxDurations;
|
|
};
|
|
|
|
}
|
|
}
|
|
|
|
#endif // mozilla_dom_TaskThrottler_h
|