Sebastian
41 lines
596 B
C++
41 lines
596 B
C++
#pragma once
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#include <memory>
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#include <mutex>
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namespace libremidi
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{
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template <auto func>
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struct deleter
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{
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template <typename U>
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void operator()(U* x) noexcept(noexcept(func(x)))
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{
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func(x);
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}
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};
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template <typename T, auto func>
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using unique_handle = std::unique_ptr<T, deleter<func>>;
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template <typename T>
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std::shared_ptr<T> instance()
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{
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static std::mutex mut;
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static std::weak_ptr<T> cache;
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std::lock_guard _{mut};
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if (auto ptr = cache.lock())
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{
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return ptr;
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}
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else
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{
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auto shared = std::make_shared<T>();
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cache = shared;
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return shared;
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}
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}
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}
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