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- /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
- /* ***** BEGIN LICENSE BLOCK *****
- * Version: MPL 1.1/GPL 2.0/LGPL 2.1
- *
- * The contents of this file are subject to the Mozilla Public License Version
- * 1.1 (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- * http://www.mozilla.org/MPL/
- *
- * Software distributed under the License is distributed on an "AS IS" basis,
- * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
- * for the specific language governing rights and limitations under the
- * License.
- *
- * The Original Code is Mozilla FastLoad code.
- *
- * The Initial Developer of the Original Code is
- * Netscape Communications Corporation.
- * Portions created by the Initial Developer are Copyright (C) 2001
- * the Initial Developer. All Rights Reserved.
- *
- * Contributor(s):
- * Brendan Eich <brendan@mozilla.org> (original author)
- *
- * Alternatively, the contents of this file may be used under the terms of
- * either of the GNU General Public License Version 2 or later (the "GPL"),
- * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
- * in which case the provisions of the GPL or the LGPL are applicable instead
- * of those above. If you wish to allow use of your version of this file only
- * under the terms of either the GPL or the LGPL, and not to allow others to
- * use your version of this file under the terms of the MPL, indicate your
- * decision by deleting the provisions above and replace them with the notice
- * and other provisions required by the GPL or the LGPL. If you do not delete
- * the provisions above, a recipient may use your version of this file under
- * the terms of any one of the MPL, the GPL or the LGPL.
- *
- * ***** END LICENSE BLOCK ***** */
-
- #ifndef nsFastLoadPtr_h___
- #define nsFastLoadPtr_h___
-
- /**
- * Mozilla FastLoad file object pointer template type.
- *
- * Use nsFastLoadPtr<T> rather than nsCOMPtr<T> when declaring a strong XPCOM
- * ref member of a data structure that's conditionally loaded at application
- * startup. You must be willing to tolerate the null mRawPtr test on every
- * dereference of this member pointer, or else copy it to a local to optimize
- * away the cost.
- */
-
- #ifndef nsCOMPtr_h___
- #include "nsCOMPtr.h"
- #endif
-
- #ifndef nsIFastLoadService_h___
- #include "nsIFastLoadService.h"
- #endif
-
- /**
- * nsFastLoadPtr is a template class, so we don't want a class static service
- * pointer member declared in nsFastLoadPtr, above. Plus, we need special
- * declaration magic to export data across DLL/DSO boundaries. So we use an
- * old-fashioned global variable that refers weakly to the one true FastLoad
- * service. This pointer is maintained by that singleton's ctor and dtor.
- */
- PR_EXPORT_DATA(nsIFastLoadService*) gFastLoadService_;
-
- template <class T>
- class nsFastLoadPtr : public nsCOMPtr<T> {
- public:
- nsDerivedSafe<T>* get() const {
- if (!this->mRawPtr) {
- gFastLoadService_->GetFastLoadReferent(
- NS_REINTERPRET_CAST(nsISupports**,
- &this->mRawPtr));
- }
- return NS_REINTERPRET_CAST(nsDerivedSafe<T>*, this->mRawPtr);
- }
-
- /**
- * Deserialize an nsFastLoadPtr from aInputStream, skipping the referent
- * object, but saving the object's offset for later deserialization.
- *
- * Lowercase name _a la_ get, because it's called the same way -- not via
- * operator->().
- */
- nsresult read(nsIObjectInputStream* aInputStream) {
- return gFastLoadService_->ReadFastLoadPtr(aInputStream,
- NS_REINTERPRET_CAST(nsISupports**,
- &this->mRawPtr));
- }
-
- /**
- * Serialize an nsFastLoadPtr reference and possibly the referent object,
- * if that object has not yet been serialized.
- *
- * Lowercase name _a la_ get, because it's called the same way -- not via
- * operator->().
- */
- nsresult write(nsIObjectOutputStream* aOutputStream) {
- return gFastLoadService_->WriteFastLoadPtr(aOutputStream,
- NS_REINTERPRET_CAST(nsISupports*,
- this->mRawPtr));
- }
- };
-
- #endif // nsFastLoadPtr_h___
-