40 lines
1.1 KiB
C++
40 lines
1.1 KiB
C++
/**
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* PANDA 3D SOFTWARE
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* Copyright (c) Carnegie Mellon University. All rights reserved.
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*
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* All use of this software is subject to the terms of the revised BSD
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* license. You should have received a copy of this license along
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* with this source code in a file named "LICENSE."
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*
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* @file configVariableBool.cxx
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* @author drose
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* @date 2004-10-20
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*/
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#include "configVariableBool.h"
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#include "mutexImpl.h"
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/**
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* Refreshes the cached value.
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*/
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void ConfigVariableBool::
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reload_value() const {
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// NB. MSVC doesn't guarantee that this mutex is initialized in a
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// thread-safe manner. But chances are that the first time this is called
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// is at static init time, when there is no risk of data races.
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// This needs to be a recursive mutex, because get_bool_word() may end up
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// indirectly querying another bool config variable.
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static ReMutexImpl lock;
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lock.lock();
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// We check again for cache validity since another thread may have beaten
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// us to the punch while we were waiting for the lock.
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if (!is_cache_valid(_local_modified)) {
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_cache = get_bool_word(0);
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mark_cache_valid(_local_modified);
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}
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lock.unlock();
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}
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