public IAsyncResult BeginAdd(Message msg, ulong id, AsyncCallback cb, object state)
{
try
{
this.rwLock.EnterWriteLock();
this.PurgeExpired();
var cmsg = new CachedMessage(msg.SignalKey, msg.Value, msg.Created, id);
if (this.messageIndex.Count + 1 < CapacityLimit)
{
// add and complete
this.AddToCache(cmsg);
return new CompletedAsyncResult(cb, state);
}
else
{
// move the 'Add' operation to pending until we've got room to
// add the item and complete once the item has been dequeued
// calling Complete on the AR
var addAsyncResult = new AddAsyncResult(cb, state);
this.pendingAdds.EnqueueAndDispatch(cmsg, addAsyncResult.Complete);
return addAsyncResult;
}
}
finally
{
this.rwLock.ExitWriteLock();
}
}
public bool TryGetNext(IEnumerable<string> eventKeys, ref ushort hwmp, out Message msg)
{
this.PurgeExpired();
msg = null;
try
{
this.rwLock.EnterReadLock();
if (this.messageIndex.Count > 0)
{
var hwm = (this.messageIndex.Keys[this.messageIndex.Count - 1] / 0x10000) * 0x10000 + hwmp;
// binary search to the right index
int i = 0, l = 0, r = this.messageIndex.Count - 1;
while (l <= r)
{
i = l + (r - l) / 2;
var v = this.messageIndex.Values[i].Id;
// check to see if value is equal to item in array
if (hwm == v)
{
break;
}
if (hwm < v)
{
r = i - 1;
}
else
{
l = i + 1;
}
}
if (i > l)
{
i = l;
}
// get the next message if there is one left
for (; i < this.messageIndex.Count; i++)
{
if (this.messageIndex.Values[i].Id <= hwm )
{
continue;
}
if (!eventKeys.Contains(this.messageIndex.Values[i].SignalKey))
{
hwmp = (ushort)(this.messageIndex.Values[i].Id & 0xffff);
continue;
}
var cmsg = this.messageIndex.Values[i];
msg = cmsg;
hwmp = (ushort)(cmsg.Id & 0xffff);
return true;
}
}
}
finally
{
this.rwLock.ExitReadLock();
}
return false;
}