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Diffstat (limited to 'sal/inc/osl/doublecheckedlocking.h')
-rw-r--r-- | sal/inc/osl/doublecheckedlocking.h | 84 |
1 files changed, 0 insertions, 84 deletions
diff --git a/sal/inc/osl/doublecheckedlocking.h b/sal/inc/osl/doublecheckedlocking.h deleted file mode 100644 index 08ef81275..000000000 --- a/sal/inc/osl/doublecheckedlocking.h +++ /dev/null @@ -1,84 +0,0 @@ -/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ -/************************************************************************* - * - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. - * - * Copyright 2000, 2010 Oracle and/or its affiliates. - * - * OpenOffice.org - a multi-platform office productivity suite - * - * This file is part of OpenOffice.org. - * - * OpenOffice.org is free software: you can redistribute it and/or modify - * it under the terms of the GNU Lesser General Public License version 3 - * only, as published by the Free Software Foundation. - * - * OpenOffice.org is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU Lesser General Public License version 3 for more details - * (a copy is included in the LICENSE file that accompanied this code). - * - * You should have received a copy of the GNU Lesser General Public License - * version 3 along with OpenOffice.org. If not, see - * <http://www.openoffice.org/license.html> - * for a copy of the LGPLv3 License. - * - ************************************************************************/ - -#if !defined INCLUDED_OSL_DOUBLECHECKEDLOCKING_H -#define INCLUDED_OSL_DOUBLECHECKEDLOCKING_H - -#if defined __cplusplus -extern "C" { -#endif /* __cplusplus */ - -/** A platform specific macro needed to make double-checked locking work. - - See - <http://www.cs.umd.edu/~pugh/java/memoryModel/DoubleCheckedLocking.html> - for a description of double-checked locking, why it is broken, and how it - can be fixed. On platforms where it is necessary, this macro will expand - to some memory barrier instruction. On many platforms, double-checked - locking works as it is, though, so on those platforms this macro will be - empty. This is a macro instead of a (C++ inline) function to allow for - maximum performance in both C and C++. - - If possible, use the rtl_Instance template instead of explicitly spelling - out the double-checked locking pattern. There are few cases where you - will have to spell it out explicitly (e.g., the logic of a certain - instance of the pattern is too complex to be mapped to the template, or - some compiler refuses to compile a template instantiation due to internal - compiler errors), though, and you should always call this macro at the - right places then: - - static T * pInstance = 0; - - T * p = pInstance; - if (!p) - { - Guard aGuard(aMutex); - p = pInstance; - if (!p) - { - p = ...; - OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER(); - pInstance = p; - } - } - else - OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER(); - return p; - - One extra advantage of this macro is that it makes it easier to find all - places where double-checked locking is used. - */ -#define OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER() /* empty */ - -#if defined __cplusplus -} -#endif /* __cplusplus */ - -#endif /* INCLUDED_OSL_DOUBLECHECKEDLOCKING_H */ - -/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |