blob: e9162cd2f92de75e9a31299978f666a7116d6def [file] [log] [blame]
// Copyright 2021 The Pigweed Authors
// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy of
// the License at
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.
#pragma once
#include <memory>
#include <mutex>
#include "pw_chrono/system_clock.h"
#include "pw_function/function.h"
namespace pw::chrono::backend {
struct NativeSystemTimer {
// Instead of using a more complex blocking timer cleanup, a shared_pointer is
// used so that the heap allocation is still valid for the detached threads
// even after the NativeSystemTimer has been destructed. Note this is shared
// with all detached threads.
struct CallbackContext {
Function<void(SystemClock::time_point expired_deadline)>&& cb)
: callback(std::move(cb)) {}
const Function<void(SystemClock::time_point expired_deadline)> callback;
// The mutex is used both to ensure the public API is threadsafe and to
// ensure that only one expiry callback is executed at time.
// A recurisve mutex is used as the timer callback must be able to invoke
// its own public API.
std::recursive_mutex mutex;
std::shared_ptr<CallbackContext> callback_context;
// This is only shared with the last active timer if there is one. Note that
// this is guarded by the callback_context's mutex.
std::shared_ptr<bool> active_timer_enabled;
using NativeSystemTimerHandle = NativeSystemTimer&;
} // namespace pw::chrono::backend