/// <summary>Add a snapshot.</summary>
/// <exception cref="Org.Apache.Hadoop.Hdfs.Protocol.SnapshotException"/>
/// <exception cref="Org.Apache.Hadoop.Hdfs.Protocol.QuotaExceededException"/>
public virtual Org.Apache.Hadoop.Hdfs.Server.Namenode.Snapshot.Snapshot AddSnapshot
(INodeDirectory snapshotRoot, int id, string name)
{
//check snapshot quota
int n = GetNumSnapshots();
if (n + 1 > snapshotQuota)
{
throw new SnapshotException("Failed to add snapshot: there are already " + n + " snapshot(s) and the snapshot quota is "
+ snapshotQuota);
}
Org.Apache.Hadoop.Hdfs.Server.Namenode.Snapshot.Snapshot s = new Org.Apache.Hadoop.Hdfs.Server.Namenode.Snapshot.Snapshot
(id, name, snapshotRoot);
byte[] nameBytes = s.GetRoot().GetLocalNameBytes();
int i = SearchSnapshot(nameBytes);
if (i >= 0)
{
throw new SnapshotException("Failed to add snapshot: there is already a " + "snapshot with the same name \""
+ Org.Apache.Hadoop.Hdfs.Server.Namenode.Snapshot.Snapshot.GetSnapshotName(s) +
"\".");
}
DirectoryWithSnapshotFeature.DirectoryDiff d = GetDiffs().AddDiff(id, snapshotRoot
);
d.SetSnapshotRoot(s.GetRoot());
snapshotsByNames.Add(-i - 1, s);
// set modification time
long now = Time.Now();
snapshotRoot.UpdateModificationTime(now, Org.Apache.Hadoop.Hdfs.Server.Namenode.Snapshot.Snapshot
.CurrentStateId);
s.GetRoot().SetModificationTime(now, Org.Apache.Hadoop.Hdfs.Server.Namenode.Snapshot.Snapshot
.CurrentStateId);
return(s);
}