PORT_Assert(signerinfo);
NSS_CMSSignerInfo_GetDigestAlgTag(NSSCMSSignerInfo *signerinfo){    SECOidData *algdata;    PORT_Assert(signerinfo);    if (!signerinfo) {        PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);        return SEC_OID_UNKNOWN;    }    algdata = SECOID_FindOID (&(signerinfo->digestAlg.algorithm));    if (algdata != NULL)	return algdata->offset;    else	return SEC_OID_UNKNOWN;}