/// <summary>Waits for a rescan to complete.</summary>
/// <remarks>
/// Waits for a rescan to complete. This doesn't guarantee consistency with
/// pending operations, only relative recency, since it will not force a new
/// rescan if a rescan is already underway.
/// <p>
/// Note that this call will release the FSN lock, so operations before and
/// after are not atomic.
/// </remarks>
public virtual void WaitForRescanIfNeeded()
{
Preconditions.CheckArgument(!namesystem.HasWriteLock(), "Must not hold the FSN write lock when waiting for a rescan."
);
Preconditions.CheckArgument(Lock.IsHeldByCurrentThread(), "Must hold the CRM lock when waiting for a rescan."
);
if (neededScanCount <= completedScanCount)
{
return;
}
// If no scan is already ongoing, mark the CRM as dirty and kick
if (curScanCount < 0)
{
doRescan.Signal();
}
// Wait until the scan finishes and the count advances
while ((!shutdown) && (completedScanCount < neededScanCount))
{
try
{
scanFinished.Await();
}
catch (Exception e)
{
Log.Warn("Interrupted while waiting for CacheReplicationMonitor" + " rescan", e);
break;
}
}
}
//
// write interface
//
public virtual void BeginWrite(int seq)
{
if (wlock.IsHeldByCurrentThread())
{
throw new IOException("BeginWrite is not reentrant");
}
#if AGNOS_TRANSPORT_DEBUG
System.Console.WriteLine("Transport.BeginWrite");
#endif
wlock.Acquire();
wseq = seq;
wbuffer.Position = 0;
wbuffer.SetLength(0);
#if AGNOS_TRANSPORT_DEBUG
System.Console.WriteLine(">> okay");
#endif
}
//
// read interface
//
public virtual int BeginRead()
{
if (rlock.IsHeldByCurrentThread())
{
throw new IOException("BeginRead is not reentrant");
}
#if AGNOS_TRANSPORT_DEBUG
System.Console.WriteLine("TransportBegin.BeginRead");
#endif
rlock.Acquire();
try {
int seq = readSInt32(inStream);
int packetLength = readSInt32(inStream);
int uncompressedLength = readSInt32(inStream);
#if AGNOS_TRANSPORT_DEBUG
System.Console.WriteLine(">> seq={0}, len={1}, uncomp={2}", seq, packetLength, uncompressedLength);
#endif
if (readStream != null)
{
throw new InvalidOperationException("readStream must be null at this point");
}
readStream = new BoundInputStream(inStream, packetLength, true, false);
if (uncompressedLength > 0)
{
readStream = new BoundInputStream(new DeflateStream(readStream, CompressionMode.Decompress, false), packetLength, false, true);
}
return(seq);
} catch (Exception) {
readStream = null;
rlock.Release();
throw;
}
}
/// <summary>Wake up the DomainSocketWatcher thread.</summary>
private void Kick()
{
System.Diagnostics.Debug.Assert((Lock.IsHeldByCurrentThread()));
if (kicked)
{
return;
}
try
{
notificationSockets[0].GetOutputStream().Write(0);
kicked = true;
}
catch (IOException e)
{
if (!closed)
{
Log.Error(this + ": error writing to notificationSockets[0]", e);
}
}
}