/* $Id: asn1-ut-null-decode.cpp $ */
/** @file
 * IPRT - ASN.1, NULL type, Decoding.
 */

/*
 * Copyright (C) 2006-2019 Oracle Corporation
 *
 * This file is part of VirtualBox Open Source Edition (OSE), as
 * available from http://www.virtualbox.org. This file is free software;
 * you can redistribute it and/or modify it under the terms of the GNU
 * General Public License (GPL) as published by the Free Software
 * Foundation, in version 2 as it comes in the "COPYING" file of the
 * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
 * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
 *
 * The contents of this file may alternatively be used under the terms
 * of the Common Development and Distribution License Version 1.0
 * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
 * VirtualBox OSE distribution, in which case the provisions of the
 * CDDL are applicable instead of those of the GPL.
 *
 * You may elect to license modified versions of this file under the
 * terms and conditions of either the GPL or the CDDL or both.
 */


/*********************************************************************************************************************************
*   Header Files                                                                                                                 *
*********************************************************************************************************************************/
#include "internal/iprt.h"
#include <iprt/asn1.h>

#include <iprt/err.h>
#include <iprt/string.h>

#include <iprt/formats/asn1.h>


RTDECL(int) RTAsn1Null_DecodeAsn1(PRTASN1CURSOR pCursor, uint32_t fFlags, PRTASN1NULL pThis, const char *pszErrorTag)
{
    int rc = RTAsn1CursorReadHdr(pCursor, &pThis->Asn1Core, pszErrorTag);
    if (RT_SUCCESS(rc))
    {
        rc = RTAsn1CursorMatchTagClassFlags(pCursor, &pThis->Asn1Core, ASN1_TAG_NULL,
                                            ASN1_TAGCLASS_UNIVERSAL | ASN1_TAGFLAG_PRIMITIVE, fFlags, pszErrorTag, "NULL");
        if (RT_SUCCESS(rc))
        {
            if (pThis->Asn1Core.cb == 0)
            {
                pThis->Asn1Core.fFlags |= RTASN1CORE_F_PRIMITE_TAG_STRUCT;
                pThis->Asn1Core.pOps    = &g_RTAsn1Null_Vtable;
                return VINF_SUCCESS;
            }

            rc = RTAsn1CursorSetInfo(pCursor, VERR_ASN1_INVALID_NULL_ENCODING,
                                     "%s: Expected NULL object to have zero length: %#x", pszErrorTag, pThis->Asn1Core.cb);
        }
    }
    RT_ZERO(*pThis);
    return rc;
}