path: root/src/OSSupport/SleepResolutionBooster.h

// SleepResolutionBooster.h

// Increases the accuracy of Sleep on Windows (GH #5140).

// This file MUST NOT be included from anywhere other than main.cpp.





#ifdef _WIN32

#include <timeapi.h>





static TIMECAPS g_Resolution;





namespace SleepResolutionBooster
{
static void Register()
{
	// Default sleep resolution on Windows isn't accurate enough (GH #5140) so try to boost it:
	if ((timeGetDevCaps(&g_Resolution, sizeof(g_Resolution)) == MMSYSERR_NOERROR) &&
		(timeBeginPeriod(g_Resolution.wPeriodMin) == MMSYSERR_NOERROR))
	{
		return;
	}

	// Max < Min sentinel for failure, to prevent bogus timeEndPeriod calls:
	g_Resolution.wPeriodMax = 0;
	g_Resolution.wPeriodMin = 1;
}

static void Unregister()
{
	if (g_Resolution.wPeriodMax >= g_Resolution.wPeriodMin)
	{
		timeEndPeriod(g_Resolution.wPeriodMin);
	}
}
};  // namespace SleepResolutionBooster

#else

namespace SleepResolutionBooster
{
static void Register() {}

static void Unregister() {}
};  // namespace SleepResolutionBooster

#endif