It uses RtlCaptureContext/RtlRestoreContext to switch context.

#include <stdio.h>
#include <thread>
#include "Fiber.h"

void fn1(void* any)
{
	printf("fn1 start\n");
	Fiber::Yield();
	printf("fn1 end\n");
}

int main()
{
	Fiber::Handle* c1 = Fiber::Spawn(fn1, (void*)1);

	while (Fiber::Active())
	{
		if (Fiber::Update() == false)
			std::this_thread::sleep_for(1s);
	}
	return 0;
}

Handle* Spawn(void(*fn)(void*), void* arg, size_t stackSize = 0)

Creates new fiber -- fn: a pointer to the function to be executed by the fiber -- arg: -- stackSize: desired stack size of fiber. if 0 stack size will have default length (about 28kb).

bool Active()

Returns true, if there is created and not finished fibers.

bool Update();

Get first ready fiber and run it. Returns true if any fiber was runned. Returns false if there is no ready fibers.

void Yield();

Suspends the execution of the current fiber. If fiber in ready state, it will be continued at next Update calls.

Handle* Self();

Returns handle of current fiber.

void Suspend(Handle* fiber);

Set fiber to waitable state. Have no effect up to Yield is called.

void Resume(Handle* fiber);

Set fiber to ready state and add to ready queue. It will be continued at next Update calls.