32 lines
700 B
C++
32 lines
700 B
C++
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#pragma once
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#include <base/types.hpp>
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namespace base {
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/// An asynchronous version of std::condition_variable.
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/// Useful for synchronizing or pausing coroutines.
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struct AsyncConditionVariable {
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AsyncConditionVariable(asio::any_io_executor exec) : timer(exec) { timer.expires_at(std::chrono::steady_clock::time_point::max()); }
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void NotifyOne() { timer.cancel_one(); }
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void NotifyAll() { timer.cancel(); }
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template <class Predicate>
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Awaitable<void> Wait(Predicate pred) {
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while(!pred()) {
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try {
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co_await timer.async_wait(asio::deferred);
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} catch(...) {
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// swallow errors
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}
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}
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co_return;
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}
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private:
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SteadyTimer timer;
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};
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} // namespace base
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