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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=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 xpcObjectHelper_h
#define xpcObjectHelper_h
// Including 'windows.h' will #define GetClassInfo to something else.
#ifdef XP_WIN
# ifdef GetClassInfo
# undef GetClassInfo
# endif
#endif
#include "mozilla/Attributes.h"
#include <stdint.h>
#include "nsCOMPtr.h"
#include "nsIClassInfo.h"
#include "nsISupports.h"
#include "nsIXPCScriptable.h"
#include "nsWrapperCache.h"
class xpcObjectHelper {
public:
explicit xpcObjectHelper(nsISupports* aObject,
nsWrapperCache* aCache = nullptr)
: mObject(aObject), mCache(aCache) {
if (!mCache && aObject) {
CallQueryInterface(aObject, &mCache);
}
}
nsISupports* Object() { return mObject; }
nsIClassInfo* GetClassInfo() {
if (!mClassInfo) {
mClassInfo = do_QueryInterface(mObject);
}
return mClassInfo;
}
// We assert that we can reach an nsIXPCScriptable somehow.
uint32_t GetScriptableFlags() {
nsCOMPtr<nsIXPCScriptable> sinfo = do_QueryInterface(mObject);
// We should have something by now.
MOZ_ASSERT(sinfo);
// Grab the flags.
return sinfo->GetScriptableFlags();
}
nsWrapperCache* GetWrapperCache() { return mCache; }
private:
xpcObjectHelper(xpcObjectHelper& aOther) = delete;
nsISupports* MOZ_UNSAFE_REF(
"xpcObjectHelper has been specifically optimized "
"to avoid unnecessary AddRefs and Releases. "
"(see bug 565742)") mObject;
nsWrapperCache* mCache;
nsCOMPtr<nsIClassInfo> mClassInfo;
};
#endif