/// <summary>
/// Gets MX records from answer collection and ORDERS them by preference.
/// NOTE: Duplicate preference records are appended to end.
/// </summary>
/// <returns></returns>
internal MX_Record[] GetMxRecordsFromAnswers()
{
MX_Record[] retVal = null;
try
{
SortedList mx = new SortedList();
ArrayList duplicateList = new ArrayList();
foreach(Dns_Answer answer in m_Answers){
if(answer.QTYPE == QTYPE.MX){
MX_Record mxRec = (MX_Record)answer.RecordObj;
if(!mx.Contains(mxRec.Preference)){
mx.Add(mxRec.Preference,mxRec);
}
else{
duplicateList.Add(mxRec);
}
}
}
MX_Record[] mxBuff = new MX_Record[mx.Count + duplicateList.Count];
mx.Values.CopyTo(mxBuff,0);
duplicateList.CopyTo(mxBuff,mx.Count);
retVal = mxBuff;
}
catch{
}
return retVal;
}
/// <summary>
/// Adds domain's MX records to cache.
/// </summary>
/// <param name="domain"></param>
/// <param name="mx"></param>
public static void AddMXToCache(string domain,MX_Record[] mx)
{
try
{
lock(m_ChacheTbl){
// Remove old cache entry, if any.
if(m_ChacheTbl.Contains(domain + "[MX]")){
m_ChacheTbl.Remove(domain + "[MX]");
}
m_ChacheTbl.Add(domain + "[MX]",new CacheEntry(mx,Environment.TickCount));
}
}
catch//(Exception x)
{
// Console.WriteLine(x.Message);
}
}
public DnsReplyCode GetMXRecords(string domain, out MX_Record[] mxRecords)
{
mxRecords = null;
ArrayList answers = QueryServer(domain, QTYPE.MX, 1).Answers;
if (answers != null)
{
SortedList mx = new SortedList();
ArrayList duplicateList = new ArrayList();
foreach (object answer in answers)
{
if (answer is MX_Record)
{
MX_Record mxRec = (MX_Record)answer;
if (!mx.Contains(mxRec.Preference))
{
mx.Add(mxRec.Preference, mxRec);
}
else
{
duplicateList.Add(mxRec);
}
}
}
mxRecords = new MX_Record[mx.Count + duplicateList.Count];
mx.Values.CopyTo(mxRecords, 0);
duplicateList.CopyTo(mxRecords, mx.Count);
}
if (mxRecords == null || mxRecords.Length == 0)
{
return(DnsReplyCode.NoEntries);
}
return(DnsReplyCode.Ok);
}
/// <summary>
/// Gets MX records.(MX records are sorted by preference, lower array element is prefered)
/// </summary>
/// <returns></returns>
public MX_Record[] GetMXRecords()
{
MX_Record[] mxRecords = (MX_Record[])FilterRecords(m_pAnswers, typeof(MX_Record)).ToArray(typeof(MX_Record));
SortedList mx = new SortedList();
ArrayList duplicateList = new ArrayList();
foreach (MX_Record mxRecord in mxRecords)
{
if (!mx.Contains(mxRecord.Preference))
{
mx.Add(mxRecord.Preference, mxRecord);
}
else
{
duplicateList.Add(mxRecord);
}
}
mxRecords = new MX_Record[mx.Count + duplicateList.Count];
mx.Values.CopyTo(mxRecords, 0);
duplicateList.CopyTo(mxRecords, mx.Count);
return(mxRecords);
}
/// <summary>
/// Gets MX records.(MX records are sorted by preference, lower array element is prefered)
/// </summary>
/// <param name="domain"></param>
/// <param name="mxRecords"></param>
/// <returns></returns>
public DnsReplyCode GetMXRecords(string domain,out MX_Record[] mxRecords)
{
mxRecords = null;
//--- Try to get MX records from cache
if(m_UseDnsCache){
mxRecords = DnsCache.GetMXFromCache(domain);
if(mxRecords != null){
// Console.WriteLine("domain:" + domain + " from cahce.");
return DnsReplyCode.Ok;
}
}
//------------------------------------//
Dns_Header header = new Dns_Header(DnsEx.ID,OPCODE.IQUERY);
Dns_Query query = new Dns_Query(domain,QTYPE.MX,1);
byte[] bQuery = query.GetQuery(header);
byte[] reply = GetQuery(bQuery,header.ID);
if(reply != null){
Dns_Answers answers = new Dns_Answers();
if(answers.ParseAnswers(reply,header.ID)){
mxRecords = answers.GetMxRecordsFromAnswers();
if(mxRecords != null){
// Add to cache
DnsCache.AddMXToCache(domain,mxRecords);
return DnsReplyCode.Ok;
}
else{
return DnsReplyCode.NoEntries;
}
}
}
return DnsReplyCode.TempError;
}
/// <summary>
/// Gets MX records.(MX records are sorted by preference, lower array element is prefered)
/// </summary>
/// <param name="domain"></param>
/// <param name="mxRecords"></param>
/// <returns></returns>
public DnsReplyCode GetMXRecords(string domain,out MX_Record[] mxRecords)
{
mxRecords = null;
ArrayList answers = QueryServer(domain,QTYPE.MX,1);
if(answers != null){
SortedList mx = new SortedList();
ArrayList duplicateList = new ArrayList();
foreach(object answer in answers){
if(answer is MX_Record){
MX_Record mxRec = (MX_Record)answer;
if(!mx.Contains(mxRec.Preference)){
mx.Add(mxRec.Preference,mxRec);
}
else{
duplicateList.Add(mxRec);
}
}
}
mxRecords = new MX_Record[mx.Count + duplicateList.Count];
mx.Values.CopyTo(mxRecords,0);
duplicateList.CopyTo(mxRecords,mx.Count);
}
if(mxRecords.Length == 0){
return DnsReplyCode.NoEntries;
}
return DnsReplyCode.Ok;
}