// REMIND: Oops, this shouldn't be public!
/// <summary> JmDNS callback to update a DNS record.</summary>
public virtual void UpdateRecord(mDNS jmdns, long now, DNSRecord rec)
{
if ((rec != null) && !rec.IsExpired(now))
{
switch (rec.type)
{
case DNSConstants.TYPE_A:
// IPv4
case DNSConstants.TYPE_AAAA: // IPv6 FIXME [PJYF Oct 14 2004] This has not been tested
if (rec.name.Equals(server))
{
addr = ((Address)rec).IPAddress;
}
break;
case DNSConstants.TYPE_SRV:
if (rec.name.Equals(QualifiedName))
{
Service srv = (Service)rec;
server = srv.server;
port = srv.port;
weight = srv.weight;
priority = srv.priority;
addr = null;
// changed to use getCache() instead - jeffs
// updateRecord(jmdns, now, (DNSRecord)jmdns.cache.get(server, TYPE_A, CLASS_IN));
UpdateRecord(jmdns, now, (DNSRecord)jmdns.Cache.get_Renamed(server, DNSConstants.TYPE_A, DNSConstants.CLASS_IN));
}
break;
case DNSConstants.TYPE_TXT:
if (rec.name.Equals(QualifiedName))
{
Text txt = (Text)rec;
text = txt.text;
}
break;
}
// Future Design Pattern
// This is done, to notify the wait loop in method
// JmDNS.getServiceInfo(type, name, timeout);
if (HasData && dns != null)
{
dns.HandleServiceResolved(this);
dns = null;
}
lock (this)
{
Monitor.PulseAll(this);
}
}
}
// Remind: Method updateRecord should receive a better name.
/// <summary> Notify all listeners that a record was updated.</summary>
internal virtual void UpdateRecord(long now, DNSRecord rec)
{
// We do not want to block the entire DNS while we are updating the record for each listener (service info)
IList listenerList = null;
lock (this)
{
listenerList = new ArrayList(listeners);
}
foreach (IDNSListener listener in listenerList)
{
listener.UpdateRecord(this, now, rec);
}
if (rec.type == DNSConstants.TYPE_PTR || rec.type == DNSConstants.TYPE_SRV)
{
IList serviceListenerList = null;
lock (this)
{
serviceListenerList = (IList)serviceListeners[rec.name.ToLower()];
// Iterate on a copy in case listeners will modify it
if (serviceListenerList != null)
{
serviceListenerList = new ArrayList(serviceListenerList);
}
}
if (serviceListenerList != null)
{
bool expired = rec.IsExpired(now);
string type = rec.Name;
string name = ((Pointer)rec).Alias;
// DNSRecord old = (DNSRecord)services.get(name.toLowerCase());
if (!expired)
{
// new record
ServiceEvent event_Renamed = new ServiceEvent(this, type, ToUnqualifiedName(type, name), null);
foreach (IServiceListener listener in serviceListenerList)
{
listener.ServiceAdded(this, event_Renamed);
}
}
else
{
// expire record
ServiceEvent event_Renamed = new ServiceEvent(this, type, ToUnqualifiedName(type, name), null);
foreach (IServiceListener listener in serviceListenerList)
{
listener.ServiceRemoved(this, event_Renamed);
}
}
}
}
}
/// <summary> Add an answer to the message.</summary>
internal void AddAnswer(DNSRecord rec, long now)
{
if (numAuthorities > 0 || numAdditionals > 0)
{
// TODO is this the right exception?
throw new Exception("Questions must be added before answers");
}
if (rec != null)
{
if ((now == 0) || !rec.IsExpired(now))
{
WriteRecord(rec, now);
numAnswers++;
}
}
}
/// <summary> Generate a possibly unique name for a service using the information we
/// have in the cache.
///
/// </summary>
/// <returns> returns true, if the name of the service info had to be changed.
/// </returns>
private bool makeServiceNameUnique(ServiceInfo info)
{
string originalQualifiedName = info.QualifiedName;
long now = (DateTime.Now.Ticks - 621355968000000000) / 10000;
bool collision;
do
{
collision = false;
// Check for collision in cache
for (DNSCache.CacheNode j = cache.find(info.QualifiedName.ToLower()); j != null; j = j.Next)
{
DNSRecord a = (DNSRecord)j.Value;
if ((a.type == DNSConstants.TYPE_SRV) && !a.IsExpired(now))
{
Service s = (Service)a;
if (s.port != info.port || !s.server.Equals(localHost.Name))
{
logger.Debug("makeServiceNameUnique() JmDNS.makeServiceNameUnique srv collision:" + a + " s.server=" + s.server + " " + localHost.Name + " equals:" + (s.server.Equals(localHost.Name)));
info.SetName(IncrementName(info.getName()));
collision = true;
break;
}
}
}
// Check for collision with other service infos published by JmDNS
object selfService = services[info.QualifiedName.ToLower()];
if (selfService != null && selfService != info)
{
info.SetName(IncrementName(info.getName()));
collision = true;
}
}while (collision);
return(!(originalQualifiedName.Equals(info.QualifiedName)));
}
/// <summary> Add a listener for a question. The listener will receive updates
/// of answers to the question as they arrive, or from the cache if they
/// are already available.
/// </summary>
internal virtual void AddListener(IDNSListener listener, DNSQuestion question)
{
long now = (DateTime.Now.Ticks - 621355968000000000) / 10000;
// add the new listener
lock (this)
{
listeners.Add(listener);
}
// report existing matched records
if (question != null)
{
for (DNSCache.CacheNode i = cache.find(question.name); i != null; i = i.Next)
{
DNSRecord c = (DNSRecord)i.Value;
if (question.IsAnsweredBy(c) && !c.IsExpired(now))
{
listener.UpdateRecord(this, now, c);
}
}
}
}
/// <summary> Handle an incoming response. Cache answers, and pass them on to
/// the appropriate questions.
/// </summary>
internal void HandleResponse(DNSIncoming msg)
{
long now = (DateTime.Now.Ticks - 621355968000000000) / 10000;
bool hostConflictDetected = false;
bool serviceConflictDetected = false;
for (int recIdx = 0; recIdx < msg.answers.Count; recIdx++)
{
DNSRecord rec = (DNSRecord)msg.answers[recIdx];
bool isInformative = false;
bool expired = rec.IsExpired(now);
// update the cache
DNSRecord c = (DNSRecord)cache.get_Renamed(rec);
if (c != null)
{
if (expired)
{
isInformative = true;
cache.remove(c);
}
else
{
c.ResetTTL(rec);
rec = c;
msg.answers[recIdx] = c; // put back into collection
}
}
else
{
if (!expired)
{
isInformative = true;
cache.add(rec);
}
}
switch (rec.type)
{
case DNSConstants.TYPE_PTR:
// handle _mdns._udp records
if (rec.Name.IndexOf("._mdns._udp.") >= 0)
{
if (!expired && rec.name.StartsWith("_services._mdns._udp."))
{
isInformative = true;
RegisterServiceType(((Pointer)rec).alias);
}
continue;
}
RegisterServiceType(rec.name);
break;
}
if ((rec.GetEntryType() == DNSConstants.TYPE_A) || (rec.GetEntryType() == DNSConstants.TYPE_AAAA))
{
hostConflictDetected |= rec.HandleResponse(this);
}
else
{
serviceConflictDetected |= rec.HandleResponse(this);
}
// notify the listeners
if (isInformative)
{
UpdateRecord(now, rec);
}
}
if (hostConflictDetected || serviceConflictDetected)
{
new Prober(this).start();
}
}
/// <summary> Add an answer to the message.</summary>
internal void AddAnswer(DNSRecord rec, long now)
{
if (numAuthorities > 0 || numAdditionals > 0)
{
// TODO is this the right exception?
throw new Exception("Questions must be added before answers");
}
if (rec != null)
{
if ((now == 0) || !rec.IsExpired(now))
{
WriteRecord(rec, now);
numAnswers++;
}
}
}
// Remind: Method updateRecord should receive a better name.
/// <summary> Notify all listeners that a record was updated.</summary>
internal virtual void UpdateRecord(long now, DNSRecord rec)
{
// We do not want to block the entire DNS while we are updating the record for each listener (service info)
IList listenerList = null;
lock (this)
{
listenerList = new ArrayList(listeners);
}
foreach (IDNSListener listener in listenerList)
{
listener.UpdateRecord(this, now, rec);
}
if (rec.type == DNSConstants.TYPE_PTR || rec.type == DNSConstants.TYPE_SRV)
{
IList serviceListenerList = null;
lock (this)
{
serviceListenerList = (IList) serviceListeners[rec.name.ToLower()];
// Iterate on a copy in case listeners will modify it
if (serviceListenerList != null)
serviceListenerList = new ArrayList(serviceListenerList);
}
if (serviceListenerList != null)
{
bool expired = rec.IsExpired(now);
string type = rec.Name;
string name = ((Pointer) rec).Alias;
// DNSRecord old = (DNSRecord)services.get(name.toLowerCase());
if (!expired)
{
// new record
ServiceEvent event_Renamed = new ServiceEvent(this, type, ToUnqualifiedName(type, name), null);
foreach (IServiceListener listener in serviceListenerList)
{
listener.ServiceAdded(this, event_Renamed);
}
}
else
{
// expire record
ServiceEvent event_Renamed = new ServiceEvent(this, type, ToUnqualifiedName(type, name), null);
foreach (IServiceListener listener in serviceListenerList)
{
listener.ServiceRemoved(this, event_Renamed);
}
}
}
}
}
// REMIND: Oops, this shouldn't be public!
/// <summary> JmDNS callback to update a DNS record.</summary>
public virtual void UpdateRecord(mDNS jmdns, long now, DNSRecord rec)
{
if ((rec != null) && !rec.IsExpired(now))
{
switch (rec.type)
{
case DNSConstants.TYPE_A:
// IPv4
case DNSConstants.TYPE_AAAA: // IPv6 FIXME [PJYF Oct 14 2004] This has not been tested
if (rec.name.Equals(server))
{
addr = ((Address) rec).IPAddress;
}
break;
case DNSConstants.TYPE_SRV:
if (rec.name.Equals(QualifiedName))
{
Service srv = (Service) rec;
server = srv.server;
port = srv.port;
weight = srv.weight;
priority = srv.priority;
addr = null;
// changed to use getCache() instead - jeffs
// updateRecord(jmdns, now, (DNSRecord)jmdns.cache.get(server, TYPE_A, CLASS_IN));
UpdateRecord(jmdns, now, (DNSRecord) jmdns.Cache.get_Renamed(server, DNSConstants.TYPE_A, DNSConstants.CLASS_IN));
}
break;
case DNSConstants.TYPE_TXT:
if (rec.name.Equals(QualifiedName))
{
Text txt = (Text) rec;
text = txt.text;
}
break;
}
// Future Design Pattern
// This is done, to notify the wait loop in method
// JmDNS.getServiceInfo(type, name, timeout);
if (HasData && dns != null)
{
dns.HandleServiceResolved(this);
dns = null;
}
lock (this)
{
Monitor.PulseAll(this);
}
}
}
