mirror of
https://gitlab.winehq.org/wine/wine-gecko.git
synced 2024-09-13 09:24:08 -07:00
83 lines
2.1 KiB
C++
83 lines
2.1 KiB
C++
/* -*- Mode: C++; tab-width: 12; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* 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_SyncRunnable_h
|
|
|
|
#include "nsThreadUtils.h"
|
|
#include "mozilla/Monitor.h"
|
|
|
|
namespace mozilla {
|
|
|
|
/**
|
|
* This class will wrap a nsIRunnable and dispatch it to the main thread
|
|
* synchronously. This is different from nsIEventTarget.DISPATCH_SYNC:
|
|
* this class does not spin the event loop waiting for the event to be
|
|
* dispatched. This means that you don't risk reentrance from pending
|
|
* messages, but you must be sure that the target thread does not ever block
|
|
* on this thread, or else you will deadlock.
|
|
*
|
|
* Typical usage:
|
|
* nsRefPtr<SyncRunnable> sr = new SyncRunnable(new myrunnable...());
|
|
* sr->DispatchToThread(t);
|
|
*
|
|
* We also provide a convenience wrapper:
|
|
* SyncRunnable::DispatchToThread(new myrunnable...());
|
|
*
|
|
*/
|
|
class SyncRunnable : public nsRunnable
|
|
{
|
|
public:
|
|
SyncRunnable(nsIRunnable* r)
|
|
: mRunnable(r)
|
|
, mMonitor("SyncRunnable")
|
|
{ }
|
|
|
|
void DispatchToThread(nsIEventTarget* thread,
|
|
bool forceDispatch = false)
|
|
{
|
|
nsresult rv;
|
|
bool on;
|
|
|
|
if (!forceDispatch) {
|
|
rv = thread->IsOnCurrentThread(&on);
|
|
MOZ_ASSERT(NS_SUCCEEDED(rv));
|
|
if (NS_SUCCEEDED(rv) && on) {
|
|
mRunnable->Run();
|
|
return;
|
|
}
|
|
}
|
|
|
|
mozilla::MonitorAutoLock lock(mMonitor);
|
|
rv = thread->Dispatch(this, NS_DISPATCH_NORMAL);
|
|
if (NS_SUCCEEDED(rv)) {
|
|
lock.Wait();
|
|
}
|
|
}
|
|
|
|
static void DispatchToThread(nsIEventTarget* thread,
|
|
nsIRunnable* r,
|
|
bool forceDispatch = false)
|
|
{
|
|
nsRefPtr<SyncRunnable> s(new SyncRunnable(r));
|
|
s->DispatchToThread(thread, forceDispatch);
|
|
}
|
|
|
|
protected:
|
|
NS_IMETHODIMP Run()
|
|
{
|
|
mRunnable->Run();
|
|
mozilla::MonitorAutoLock(mMonitor).Notify();
|
|
return NS_OK;
|
|
}
|
|
|
|
private:
|
|
nsCOMPtr<nsIRunnable> mRunnable;
|
|
mozilla::Monitor mMonitor;
|
|
};
|
|
|
|
} // namespace mozilla
|
|
|
|
#endif // mozilla_SyncRunnable_h
|