RtlStringCbCopyUnicodeString - NtDoc

#ifndef _NTSTRSAFE_H_INCLUDED_
#ifndef NTSTRSAFE_LIB_IMPL
#ifndef NTSTRSAFE_NO_UNICODE_STRING_FUNCTIONS

NTSTRSAFEDDI
    RtlStringCbCopyUnicodeString(
            _Out_writes_bytes_(cbDest) NTSTRSAFE_PWSTR pszDest,
            _In_ size_t cbDest,
            _In_ PCUNICODE_STRING SourceString)
{
    NTSTATUS status;
    size_t cchDest = cbDest / sizeof(wchar_t);

    status = RtlStringValidateDestW(pszDest,
            cchDest,
            NTSTRSAFE_UNICODE_STRING_MAX_CCH);
    if (NT_SUCCESS(status))
    {
        wchar_t* pszSrc;
        size_t cchSrcLength;

        status = RtlUnicodeStringValidateSrcWorker(SourceString,
                &pszSrc,
                &cchSrcLength,
                NTSTRSAFE_UNICODE_STRING_MAX_CCH,
                0);

        if (NT_SUCCESS(status))
        {
            status = RtlStringCopyWideCharArrayWorker(pszDest,
                    cchDest,
                    NULL,
                    pszSrc,
                    cchSrcLength);
        }
        else
        {
            *pszDest = L'\0';
        }
    }

    return status;
}

#endif
#endif
#endif
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