| /* -*- Mode: IDL; 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.org code. |
| * |
| * The Initial Developer of the Original Code is |
| * Netscape Communications Corporation. |
| * Portions created by the Initial Developer are Copyright (C) 1998 |
| * the Initial Developer. All Rights Reserved. |
| * |
| * Contributor(s): |
| * Scott Collins <scc@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 nsIWeakReferenceUtils_h__ |
| #define nsIWeakReferenceUtils_h__ |
| |
| #ifndef nsCOMPtr_h__ |
| #include "nsCOMPtr.h" |
| #endif |
| |
| typedef nsCOMPtr<nsIWeakReference> nsWeakPtr; |
| |
| /** |
| * |
| */ |
| |
| // a type-safe shortcut for calling the |QueryReferent()| member function |
| // T must inherit from nsIWeakReference, but the cast may be ambiguous. |
| template <class T, class DestinationType> |
| inline |
| nsresult |
| CallQueryReferent( T* aSource, DestinationType** aDestination ) |
| { |
| NS_PRECONDITION(aSource, "null parameter"); |
| NS_PRECONDITION(aDestination, "null parameter"); |
| |
| return aSource->QueryReferent(NS_GET_TEMPLATE_IID(DestinationType), |
| reinterpret_cast<void**>(aDestination)); |
| } |
| |
| |
| class NS_COM_GLUE nsQueryReferent : public nsCOMPtr_helper |
| { |
| public: |
| nsQueryReferent( nsIWeakReference* aWeakPtr, nsresult* error ) |
| : mWeakPtr(aWeakPtr), |
| mErrorPtr(error) |
| { |
| // nothing else to do here |
| } |
| |
| virtual nsresult NS_FASTCALL operator()( const nsIID& aIID, void** ) const; |
| |
| private: |
| nsIWeakReference* mWeakPtr; |
| nsresult* mErrorPtr; |
| }; |
| |
| inline |
| const nsQueryReferent |
| do_QueryReferent( nsIWeakReference* aRawPtr, nsresult* error = 0 ) |
| { |
| return nsQueryReferent(aRawPtr, error); |
| } |
| |
| |
| /** |
| * Deprecated, use |do_GetWeakReference| instead. |
| */ |
| extern NS_COM_GLUE |
| nsIWeakReference* |
| NS_GetWeakReference( nsISupports* , nsresult* aResult=0 ); |
| |
| /** |
| * |do_GetWeakReference| is a convenience function that bundles up all the work needed |
| * to get a weak reference to an arbitrary object, i.e., the |QueryInterface|, test, and |
| * call through to |GetWeakReference|, and put it into your |nsCOMPtr|. |
| * It is specifically designed to cooperate with |nsCOMPtr| (or |nsWeakPtr|) like so: |
| * |nsWeakPtr myWeakPtr = do_GetWeakReference(aPtr);|. |
| */ |
| inline |
| already_AddRefed<nsIWeakReference> |
| do_GetWeakReference( nsISupports* aRawPtr, nsresult* error = 0 ) |
| { |
| return NS_GetWeakReference(aRawPtr, error); |
| } |
| |
| inline |
| void |
| do_GetWeakReference( nsIWeakReference* aRawPtr, nsresult* error = 0 ) |
| { |
| // This signature exists solely to _stop_ you from doing a bad thing. |
| // Saying |do_GetWeakReference()| on a weak reference itself, |
| // is very likely to be a programmer error. |
| } |
| |
| template <class T> |
| inline |
| void |
| do_GetWeakReference( already_AddRefed<T>& ) |
| { |
| // This signature exists solely to _stop_ you from doing the bad thing. |
| // Saying |do_GetWeakReference()| on a pointer that is not otherwise owned by |
| // someone else is an automatic leak. See <http://bugzilla.mozilla.org/show_bug.cgi?id=8221>. |
| } |
| |
| template <class T> |
| inline |
| void |
| do_GetWeakReference( already_AddRefed<T>&, nsresult* ) |
| { |
| // This signature exists solely to _stop_ you from doing the bad thing. |
| // Saying |do_GetWeakReference()| on a pointer that is not otherwise owned by |
| // someone else is an automatic leak. See <http://bugzilla.mozilla.org/show_bug.cgi?id=8221>. |
| } |
| |
| #endif |