RtlStringCchLengthA - NtDoc

#ifndef _NTSTRSAFE_H_INCLUDED_
#ifndef NTSTRSAFE_LIB_IMPL
#ifndef NTSTRSAFE_NO_CCH_FUNCTIONS

_Must_inspect_result_
NTSTRSAFEDDI
    RtlStringCchLengthA(
            _In_reads_or_z_(cchMax) STRSAFE_PCNZCH psz,
            _In_ _In_range_(1, NTSTRSAFE_MAX_CCH) size_t cchMax,
            _Out_opt_ _Deref_out_range_(<, cchMax) _Deref_out_range_(<=, _String_length_(psz)) size_t* pcchLength)
{
    NTSTATUS status;

    if ((psz == NULL) || (cchMax > NTSTRSAFE_MAX_CCH))
    {
        status = STATUS_INVALID_PARAMETER;
    }
    else
    {
        status = RtlStringLengthWorkerA(psz, cchMax, pcchLength);
    }

    if (!NT_SUCCESS(status) && pcchLength)
    {
        *pcchLength = 0;
    }

    return status;
}

#endif
#endif
#endif
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