mirror of https://github.com/yuzu-emu/yuzu
66 lines
2.0 KiB
C++
66 lines
2.0 KiB
C++
// SPDX-FileCopyrightText: Copyright 2020 yuzu Emulator Project
|
|
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
|
|
#pragma once
|
|
|
|
#include <functional>
|
|
#include <memory>
|
|
|
|
namespace boost::context::detail {
|
|
struct transfer_t;
|
|
}
|
|
|
|
namespace Common {
|
|
|
|
/**
|
|
* Fiber class
|
|
* a fiber is a userspace thread with it's own context. They can be used to
|
|
* implement coroutines, emulated threading systems and certain asynchronous
|
|
* patterns.
|
|
*
|
|
* This class implements fibers at a low level, thus allowing greater freedom
|
|
* to implement such patterns. This fiber class is 'threadsafe' only one fiber
|
|
* can be running at a time and threads will be locked while trying to yield to
|
|
* a running fiber until it yields. WARNING exchanging two running fibers between
|
|
* threads will cause a deadlock. In order to prevent a deadlock, each thread should
|
|
* have an intermediary fiber, you switch to the intermediary fiber of the current
|
|
* thread and then from it switch to the expected fiber. This way you can exchange
|
|
* 2 fibers within 2 different threads.
|
|
*/
|
|
class Fiber {
|
|
public:
|
|
Fiber(std::function<void()>&& entry_point_func);
|
|
~Fiber();
|
|
|
|
Fiber(const Fiber&) = delete;
|
|
Fiber& operator=(const Fiber&) = delete;
|
|
|
|
Fiber(Fiber&&) = default;
|
|
Fiber& operator=(Fiber&&) = default;
|
|
|
|
/// Yields control from Fiber 'from' to Fiber 'to'
|
|
/// Fiber 'from' must be the currently running fiber.
|
|
static void YieldTo(std::weak_ptr<Fiber> weak_from, Fiber& to);
|
|
[[nodiscard]] static std::shared_ptr<Fiber> ThreadToFiber();
|
|
|
|
void SetRewindPoint(std::function<void()>&& rewind_func);
|
|
|
|
void Rewind();
|
|
|
|
/// Only call from main thread's fiber
|
|
void Exit();
|
|
|
|
private:
|
|
Fiber();
|
|
|
|
void OnRewind(boost::context::detail::transfer_t& transfer);
|
|
void Start(boost::context::detail::transfer_t& transfer);
|
|
static void FiberStartFunc(boost::context::detail::transfer_t transfer);
|
|
static void RewindStartFunc(boost::context::detail::transfer_t transfer);
|
|
|
|
struct FiberImpl;
|
|
std::unique_ptr<FiberImpl> impl;
|
|
};
|
|
|
|
} // namespace Common
|