7f19d64164
git-subtree-dir: third_party/immer git-subtree-split: ad3e3556d38bb75966dd24c61a774970a7c7957e
40 lines
899 B
C++
40 lines
899 B
C++
//
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// immer: immutable data structures for C++
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// Copyright (C) 2016, 2017, 2018 Juan Pedro Bolivar Puente
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//
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// This software is distributed under the Boost Software License, Version 1.0.
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// See accompanying file LICENSE or copy at http://boost.org/LICENSE_1_0.txt
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//
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#pragma once
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#include <immer/refcount/no_refcount_policy.hpp>
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#include <atomic>
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#include <utility>
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namespace immer {
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/*!
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* A reference counting policy implemented using a raw `int` count.
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* It is **not thread-safe**.
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*/
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struct unsafe_refcount_policy
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{
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using spinlock_type = no_spinlock;
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mutable int refcount;
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unsafe_refcount_policy()
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: refcount{1} {};
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unsafe_refcount_policy(disowned)
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: refcount{0}
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{}
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void inc() { ++refcount; }
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bool dec() { return --refcount == 0; }
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void dec_unsafe() { --refcount; }
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bool unique() { return refcount == 1; }
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};
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} // namespace immer
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