llptrto.h
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- /**
- * @file llptrto.h
- * @author Nat Goodspeed
- * @date 2008-08-19
- * @brief LLPtrTo<TARGET> is a template helper to pick either TARGET* or -- when
- * TARGET is a subclass of LLRefCount or LLThreadSafeRefCount --
- * LLPointer<TARGET>. LLPtrTo<> chooses whichever pointer type is best.
- *
- * $LicenseInfo:firstyear=2008&license=viewergpl$
- *
- * Copyright (c) 2008-2010, Linden Research, Inc.
- *
- * Second Life Viewer Source Code
- * The source code in this file ("Source Code") is provided by Linden Lab
- * to you under the terms of the GNU General Public License, version 2.0
- * ("GPL"), unless you have obtained a separate licensing agreement
- * ("Other License"), formally executed by you and Linden Lab. Terms of
- * the GPL can be found in doc/GPL-license.txt in this distribution, or
- * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
- *
- * There are special exceptions to the terms and conditions of the GPL as
- * it is applied to this Source Code. View the full text of the exception
- * in the file doc/FLOSS-exception.txt in this software distribution, or
- * online at
- * http://secondlifegrid.net/programs/open_source/licensing/flossexception
- *
- * By copying, modifying or distributing this software, you acknowledge
- * that you have read and understood your obligations described above,
- * and agree to abide by those obligations.
- *
- * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
- * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
- * COMPLETENESS OR PERFORMANCE.
- * $/LicenseInfo$
- */
- #if ! defined(LL_LLPTRTO_H)
- #define LL_LLPTRTO_H
- #include "llpointer.h"
- #include "llrefcount.h" // LLRefCount
- #include "llthread.h" // LLThreadSafeRefCount
- #include <boost/type_traits/is_base_of.hpp>
- #include <boost/type_traits/remove_pointer.hpp>
- #include <boost/utility/enable_if.hpp>
- /**
- * LLPtrTo<TARGET>::type is either of two things:
- *
- * * When TARGET is a subclass of either LLRefCount or LLThreadSafeRefCount,
- * LLPtrTo<TARGET>::type is LLPointer<TARGET>.
- * * Otherwise, LLPtrTo<TARGET>::type is TARGET*.
- *
- * This way, a class template can use LLPtrTo<TARGET>::type to select an
- * appropriate pointer type to store.
- */
- template <class T, class ENABLE=void>
- struct LLPtrTo
- {
- typedef T* type;
- };
- /// specialize for subclasses of LLRefCount
- template <class T>
- struct LLPtrTo<T, typename boost::enable_if< boost::is_base_of<LLRefCount, T> >::type>
- {
- typedef LLPointer<T> type;
- };
- /// specialize for subclasses of LLThreadSafeRefCount
- template <class T>
- struct LLPtrTo<T, typename boost::enable_if< boost::is_base_of<LLThreadSafeRefCount, T> >::type>
- {
- typedef LLPointer<T> type;
- };
- /**
- * LLRemovePointer<PTRTYPE>::type gets you the underlying (pointee) type.
- */
- template <typename PTRTYPE>
- struct LLRemovePointer
- {
- typedef typename boost::remove_pointer<PTRTYPE>::type type;
- };
- /// specialize for LLPointer<SOMECLASS>
- template <typename SOMECLASS>
- struct LLRemovePointer< LLPointer<SOMECLASS> >
- {
- typedef SOMECLASS type;
- };
- #endif /* ! defined(LL_LLPTRTO_H) */