RtlUShortToChar - NtDoc

#ifndef _NTINTSAFE_H_INCLUDED_
#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP | WINAPI_PARTITION_SYSTEM | WINAPI_PARTITION_GAMES)

//
// USHORT -> CHAR conversion
//
__forceinline
NTSTATUS
RtlUShortToChar(
    _In_ USHORT usOperand,
    _Out_ _Deref_out_range_(==, usOperand) CHAR* pch)
{
#ifdef _CHAR_UNSIGNED
    return RtlUShortToUChar(usOperand, (UCHAR*)pch);
#else
    return RtlUShortToInt8(usOperand, (INT8*)pch);
#endif // _CHAR_UNSIGNED
}

#endif
#endif
View code on GitHub