#ifdef _WIN32

#include <windows.h>

#if defined(_MSC_VER) || defined(_MSC_EXTENSIONS)

  #define U64(x) x##Ui64

#else

  #define U64(x) x##ULL

#endif

#define DELTA_EPOCH_IN_100NS  U64(116444736000000000)

static long ticks_to_nanos(LONGLONG subsecond_time, LONGLONG frequency)

{

    return (long)((1e9 * subsecond_time) / frequency);

}

static ULONGLONG to_quad_100ns(FILETIME ft)

{

    ULARGE_INTEGER li;

    li.LowPart = ft.dwLowDateTime;

    li.HighPart = ft.dwHighDateTime;

    return li.QuadPart;

}

static void to_timespec_from_100ns(ULONGLONG t_100ns, long long *t)

{

    t[0] = (long)(t_100ns / 10000000UL);

    t[1] = 100*(long)(t_100ns % 10000000UL);

}

void hs_clock_win32_gettime_monotonic(long long* t)

{

   LARGE_INTEGER time;

   LARGE_INTEGER frequency;

   QueryPerformanceCounter(&time);

   QueryPerformanceFrequency(&frequency);

   // seconds

   t[0] = time.QuadPart / frequency.QuadPart;

   // nanos =

   t[1] = ticks_to_nanos(time.QuadPart % frequency.QuadPart, frequency.QuadPart);

}

void hs_clock_win32_gettime_realtime(long long* t)

{

    FILETIME ft;

    ULONGLONG tmp;

    GetSystemTimeAsFileTime(&ft;;

    tmp = to_quad_100ns(ft);

    tmp -= DELTA_EPOCH_IN_100NS;

    to_timespec_from_100ns(tmp, t);

}

void hs_clock_win32_gettime_processtime(long long* t)

{

    FILETIME creation_time, exit_time, kernel_time, user_time;

    ULONGLONG time;

    GetProcessTimes(GetCurrentProcess(), &creation_time, &exit_time, &kernel_time, &user_time);

    // Both kernel and user, acc. to http://www.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap03.html#tag_03_117

    time = to_quad_100ns(user_time) + to_quad_100ns(kernel_time);

    to_timespec_from_100ns(time, t);

}

void hs_clock_win32_gettime_threadtime(long long* t)

{

    FILETIME creation_time, exit_time, kernel_time, user_time;

    ULONGLONG time;

    GetThreadTimes(GetCurrentThread(), &creation_time, &exit_time, &kernel_time, &user_time);

    // Both kernel and user, acc. to http://www.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap03.html#tag_03_117

    time = to_quad_100ns(user_time) + to_quad_100ns(kernel_time);

    to_timespec_from_100ns(time, t);

}

void hs_clock_win32_getres_monotonic(long long* t)

{

    LARGE_INTEGER frequency;

    QueryPerformanceFrequency(&frequency);

    ULONGLONG resolution = U64(1000000000)/frequency.QuadPart;

    t[0] = resolution / U64(1000000000);

    t[1] = resolution % U64(1000000000);

}

void hs_clock_win32_getres_realtime(long long* t)

{

    t[0] = 0;

    t[1] = 100;

}

void hs_clock_win32_getres_processtime(long long* t)

{

    t[0] = 0;

    t[1] = 100;

}

void hs_clock_win32_getres_threadtime(long long* t)

{

    t[0] = 0;

    t[1] = 100;

}

#endif	/* _WIN32 */