50 lines
1.0 KiB
C++
50 lines
1.0 KiB
C++
// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
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// Distributed under the MIT License (http://opensource.org/licenses/MIT)
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#pragma once
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#include <atomic>
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#include <utility>
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// null, no cost dummy "mutex" and dummy "atomic" int
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namespace spdlog {
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namespace details {
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struct null_mutex
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{
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void lock() const {}
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void unlock() const {}
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bool try_lock() const
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{
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return true;
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}
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};
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struct null_atomic_int
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{
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int value;
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null_atomic_int() = default;
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explicit null_atomic_int(int new_value)
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: value(new_value)
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{}
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int load(std::memory_order = std::memory_order_relaxed) const
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{
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return value;
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}
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void store(int new_value, std::memory_order = std::memory_order_relaxed)
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{
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value = new_value;
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}
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int exchange(int new_value, std::memory_order = std::memory_order_relaxed)
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{
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std::swap(new_value, value);
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return new_value; // return value before the call
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}
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};
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} // namespace details
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} // namespace spdlog
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