RtlULongPtrToLongPtr - NtDoc

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

//        
// ULONG_PTR -> LONG_PTR conversion
//
_Must_inspect_result_
__inline
NTSTATUS
RtlULongPtrToLongPtr(
    _In_ ULONG_PTR ulOperand,
    _Out_ _Deref_out_range_(==, ulOperand) LONG_PTR* plResult)
{
    NTSTATUS status;
    
    if (ulOperand <= LONG_PTR_MAX)
    {
        *plResult = (LONG_PTR)ulOperand;
        status = STATUS_SUCCESS;
    }
    else
    {
        *plResult = LONG_PTR_ERROR;
        status = STATUS_INTEGER_OVERFLOW;
    }
    
    return status;
}

#endif
#endif
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