gecko-dev/dom/indexedDB/AsyncConnectionHelper.h
2012-05-21 12:12:37 +01:00

187 lines
5.4 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 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_indexeddb_asyncconnectionhelper_h__
#define mozilla_dom_indexeddb_asyncconnectionhelper_h__
// Only meant to be included in IndexedDB source files, not exported.
#include "DatabaseInfo.h"
#include "IndexedDatabase.h"
#include "IDBDatabase.h"
#include "IDBRequest.h"
#include "mozIStorageProgressHandler.h"
#include "nsIRunnable.h"
#include "nsDOMEvent.h"
class mozIStorageConnection;
class nsIEventTarget;
BEGIN_INDEXEDDB_NAMESPACE
class IDBTransaction;
// A common base class for AsyncConnectionHelper and OpenDatabaseHelper that
// IDBRequest can use.
class HelperBase : public nsIRunnable
{
friend class IDBRequest;
public:
virtual nsresult GetResultCode() = 0;
virtual nsresult GetSuccessResult(JSContext* aCx,
jsval* aVal) = 0;
protected:
HelperBase(IDBRequest* aRequest)
: mRequest(aRequest)
{ }
virtual ~HelperBase();
/**
* Helper to wrap a native into a jsval. Uses the global object of the request
* to parent the native.
*/
nsresult WrapNative(JSContext* aCx,
nsISupports* aNative,
jsval* aResult);
/**
* Gives the subclass a chance to release any objects that must be released
* on the main thread, regardless of success or failure. Subclasses that
* implement this method *MUST* call the base class implementation as well.
*/
virtual void ReleaseMainThreadObjects();
nsRefPtr<IDBRequest> mRequest;
};
/**
* Must be subclassed. The subclass must implement DoDatabaseWork. It may then
* choose to implement OnSuccess and OnError depending on the needs of the
* subclass. If the default implementation of OnSuccess is desired then the
* subclass can implement GetSuccessResult to properly set the result of the
* success event. Call Dispatch to start the database operation. Must be created
* and Dispatched from the main thread only. Target thread may not be the main
* thread.
*/
class AsyncConnectionHelper : public HelperBase,
public mozIStorageProgressHandler
{
public:
NS_DECL_ISUPPORTS
NS_DECL_NSIRUNNABLE
NS_DECL_MOZISTORAGEPROGRESSHANDLER
nsresult Dispatch(nsIEventTarget* aDatabaseThread);
// Only for transactions!
nsresult DispatchToTransactionPool();
void SetError(nsresult aErrorCode)
{
NS_ASSERTION(NS_FAILED(aErrorCode), "Not a failure code!");
mResultCode = aErrorCode;
}
static IDBTransaction* GetCurrentTransaction();
bool HasTransaction()
{
return mTransaction;
}
nsISupports* GetSource()
{
return mRequest ? mRequest->Source() : nsnull;
}
nsresult GetResultCode()
{
return mResultCode;
}
protected:
AsyncConnectionHelper(IDBDatabase* aDatabase,
IDBRequest* aRequest);
AsyncConnectionHelper(IDBTransaction* aTransaction,
IDBRequest* aRequest);
virtual ~AsyncConnectionHelper();
/**
* This is called on the main thread after Dispatch is called but before the
* runnable is actually dispatched to the database thread. Allows the subclass
* to initialize itself.
*/
virtual nsresult Init();
/**
* This callback is run on the database thread.
*/
virtual nsresult DoDatabaseWork(mozIStorageConnection* aConnection) = 0;
/**
* This function returns the event to be dispatched at the request when
* OnSuccess is called. A subclass can override this to fire an event other
* than "success" at the request.
*/
virtual already_AddRefed<nsDOMEvent> CreateSuccessEvent();
/**
* This callback is run on the main thread if DoDatabaseWork returned NS_OK.
* The default implementation fires a "success" DOM event with its target set
* to the request. Returning anything other than NS_OK from the OnSuccess
* callback will trigger the OnError callback.
*/
virtual nsresult OnSuccess();
/**
* This callback is run on the main thread if DoDatabaseWork or OnSuccess
* returned an error code. The default implementation fires an "error" DOM
* event with its target set to the request.
*/
virtual void OnError();
/**
* This function is called by the request on the main thread when script
* accesses the result property of the request.
*/
virtual nsresult GetSuccessResult(JSContext* aCx,
jsval* aVal);
/**
* Gives the subclass a chance to release any objects that must be released
* on the main thread, regardless of success or failure. Subclasses that
* implement this method *MUST* call the base class implementation as well.
*/
virtual void ReleaseMainThreadObjects();
/**
* Helper to make a JS array object out of an array of clone buffers.
*/
static nsresult ConvertCloneReadInfosToArray(
JSContext* aCx,
nsTArray<StructuredCloneReadInfo>& aReadInfos,
jsval* aResult);
protected:
nsRefPtr<IDBDatabase> mDatabase;
nsRefPtr<IDBTransaction> mTransaction;
private:
nsCOMPtr<mozIStorageProgressHandler> mOldProgressHandler;
nsresult mResultCode;
bool mDispatched;
};
END_INDEXEDDB_NAMESPACE
#endif // mozilla_dom_indexeddb_asyncconnectionhelper_h__