56 lines
1.1 KiB
C
56 lines
1.1 KiB
C
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/*
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* Copyright 2001-2005, Haiku.
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* Distributed under the terms of the MIT License.
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*
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* Authors:
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* DarkWyrm <bpmagic@columbus.rr.com>
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* Axel Dörfler, axeld@pinc-software.de
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*/
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#ifndef REFERENCE_COUNTING_H
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#define REFERENCE_COUNTING_H
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#include <SupportDefs.h>
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/*!
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\class ReferenceCounting ReferenceCounting.h
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\brief Base class for reference counting objects
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ReferenceCounting objects track dependencies upon a particular object. In this way,
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it is possible to ensure that a shared resource is not deleted if something else
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needs it. How the dependency tracking is done largely depends on the child class.
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*/
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class ReferenceCounting {
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public:
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ReferenceCounting()
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: fReferenceCount(1) {}
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virtual ~ReferenceCounting() {}
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inline void Acquire();
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inline bool Release();
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private:
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int32 fReferenceCount;
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};
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inline void
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ReferenceCounting::Acquire()
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{
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atomic_add(&fReferenceCount, 1);
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}
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inline bool
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ReferenceCounting::Release()
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{
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if (atomic_add(&fReferenceCount, -1) == 1) {
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delete this;
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return true;
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}
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return false;
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}
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#endif /* REFERENCE_COUNTING_H */
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