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clio/src/util/Repeat.hpp
2025-01-09 14:47:08 +00:00

115 lines
3.6 KiB
C++

//------------------------------------------------------------------------------
/*
This file is part of clio: https://github.com/XRPLF/clio
Copyright (c) 2024, the clio developers.
Permission to use, copy, modify, and distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
//==============================================================================
#pragma once
#include "util/Assert.hpp"
#include <boost/asio/io_context.hpp>
#include <boost/asio/post.hpp>
#include <boost/asio/steady_timer.hpp>
#include <atomic>
#include <chrono>
#include <concepts>
#include <memory>
#include <semaphore>
#include <utility>
namespace util {
/**
* @brief A class to repeat some action at a regular interval
* @note io_context must be stopped before the Repeat object is destroyed. Otherwise it is undefined behavior
*/
class Repeat {
struct Control {
boost::asio::steady_timer timer;
std::atomic_bool stopping{true};
std::binary_semaphore semaphore{0};
Control(auto& ctx) : timer(ctx)
{
}
};
std::shared_ptr<Control> control_;
public:
/**
* @brief Construct a new Repeat object
* @note The `ctx` parameter is `auto` so that this util supports `strand` and `thread_pool` as well as `io_context`
*
* @param ctx The io_context-like object to use
*/
Repeat(auto& ctx) : control_(std::make_unique<Control>(ctx))
{
}
Repeat(Repeat const&) = delete;
Repeat&
operator=(Repeat const&) = delete;
Repeat(Repeat&&) = default;
Repeat&
operator=(Repeat&&) = default;
/**
* @brief Stop repeating
* @note This method will block to ensure the repeating is actually stopped. But blocking time should be very short.
*/
void
stop();
/**
* @brief Start asynchronously repeating
* @note stop() must be called before start() is called for the second time
*
* @tparam Action The action type
* @param interval The interval to repeat
* @param action The action to call regularly
*/
template <std::invocable Action>
void
start(std::chrono::steady_clock::duration interval, Action&& action)
{
ASSERT(control_->stopping, "Should be stopped before starting");
control_->stopping = false;
startImpl(control_, interval, std::forward<Action>(action));
}
private:
template <std::invocable Action>
static void
startImpl(std::shared_ptr<Control> control, std::chrono::steady_clock::duration interval, Action&& action)
{
control->timer.expires_after(interval);
control->timer.async_wait([control, interval, action = std::forward<Action>(action)](auto const& ec) mutable {
if (ec or control->stopping) {
control->semaphore.release();
return;
}
action();
startImpl(std::move(control), interval, std::forward<Action>(action));
});
}
};
} // namespace util