michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set ts=2 et sw=2 tw=80: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef mozilla_dom_file_asynchelper_h__
michael@0: #define mozilla_dom_file_asynchelper_h__
michael@0: 
michael@0: #include "FileCommon.h"
michael@0: 
michael@0: #include "nsIRequest.h"
michael@0: #include "nsIRunnable.h"
michael@0: 
michael@0: class nsIRequestObserver;
michael@0: 
michael@0: BEGIN_FILE_NAMESPACE
michael@0: 
michael@0: /**
michael@0:  * Must be subclassed. The subclass must implement DoStreamWork.
michael@0:  * Async operations that are not supported in necko (truncate, flush, etc.)
michael@0:  * should use this helper. Call AsyncWork to invoke the operation.
michael@0:  */
michael@0: class AsyncHelper : public nsIRunnable,
michael@0:                     public nsIRequest
michael@0: {
michael@0: public:
michael@0:   NS_DECL_THREADSAFE_ISUPPORTS
michael@0:   NS_DECL_NSIRUNNABLE
michael@0:   NS_DECL_NSIREQUEST
michael@0: 
michael@0:   nsresult
michael@0:   AsyncWork(nsIRequestObserver* aObserver, nsISupports* aCtxt);
michael@0: 
michael@0: protected:
michael@0:   AsyncHelper(nsISupports* aStream)
michael@0:   : mStream(aStream),
michael@0:     mStatus(NS_OK)
michael@0:   { }
michael@0: 
michael@0:   virtual ~AsyncHelper()
michael@0:   { }
michael@0: 
michael@0:   virtual nsresult
michael@0:   DoStreamWork(nsISupports* aStream) = 0;
michael@0: 
michael@0: private:
michael@0:   nsCOMPtr<nsISupports> mStream;
michael@0:   nsCOMPtr<nsIRequestObserver> mObserver;
michael@0: 
michael@0:   nsresult mStatus;
michael@0: };
michael@0: 
michael@0: END_FILE_NAMESPACE
michael@0: 
michael@0: #endif // mozilla_dom_file_asynchelper_h__