/*
* Copyright (C) 2011 Google 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 AND ITS CONTRIBUTORS "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 OR ITS 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.
*/
#ifndef WebThread_h
#define WebThread_h
#include "WebCommon.h"
namespace blink {
// Provides an interface to an embedder-defined thread implementation.
//
// Deleting the thread blocks until all pending, non-delayed tasks have been
// run.
class BLINK_PLATFORM_EXPORT WebThread {
public:
class Task {
public:
virtual ~Task() { }
virtual void run() = 0;
};
class BLINK_PLATFORM_EXPORT TaskObserver {
public:
virtual ~TaskObserver() { }
virtual void willProcessTask() = 0;
virtual void didProcessTask() = 0;
};
// postTask() and postDelayedTask() take ownership of the passed Task
// object. It is safe to invoke postTask() and postDelayedTask() from any
// thread.
virtual void postTask(Task*) = 0;
virtual void postDelayedTask(Task*, long long delayMs) = 0;
virtual bool isCurrentThread() const = 0;
virtual void addTaskObserver(TaskObserver*) { }
virtual void removeTaskObserver(TaskObserver*) { }
// enterRunLoop() processes tasks posted to this WebThread. This call does not return until some task calls exitRunLoop().
// WebThread does not support nesting, meaning that once the run loop is entered for a given WebThread it is not valid to
// call enterRunLoop() again.
virtual void enterRunLoop() = 0;
// exitRunLoop() runs tasks until there are no tasks available to run, then returns control to the caller of enterRunLoop().
// Must be called when the WebThread is running.
virtual void exitRunLoop() = 0;
virtual ~WebThread() { }
};
} // namespace blink
#endif