/// <summary>Create a snapshot of the given path.</summary>
/// <remarks>
/// Create a snapshot of the given path.
/// It is assumed that the caller will perform synchronization.
/// </remarks>
/// <param name="iip">the INodes resolved from the snapshottable directory's path</param>
/// <param name="snapshotName">The name of the snapshot.</param>
/// <exception cref="System.IO.IOException">
/// Throw IOException when 1) the given path does not lead to an
/// existing snapshottable directory, and/or 2) there exists a
/// snapshot with the given name for the directory, and/or 3)
/// snapshot number exceeds quota
/// </exception>
public virtual string CreateSnapshot(INodesInPath iip, string snapshotRoot, string
snapshotName)
{
INodeDirectory srcRoot = GetSnapshottableRoot(iip);
if (snapshotCounter == GetMaxSnapshotID())
{
// We have reached the maximum allowable snapshot ID and since we don't
// handle rollover we will fail all subsequent snapshot creation
// requests.
//
throw new SnapshotException("Failed to create the snapshot. The FileSystem has run out of "
+ "snapshot IDs and ID rollover is not supported.");
}
srcRoot.AddSnapshot(snapshotCounter, snapshotName);
//create success, update id
snapshotCounter++;
numSnapshots.GetAndIncrement();
return(Org.Apache.Hadoop.Hdfs.Server.Namenode.Snapshot.Snapshot.GetSnapshotPath(snapshotRoot
, snapshotName));
}