/// <summary>Get a listing of all the snapshots of a snapshottable directory</summary>
/// <exception cref="System.IO.IOException"/>
private static DirectoryListing GetSnapshotsListing(FSDirectory fsd, string src,
byte[] startAfter)
{
Preconditions.CheckState(fsd.HasReadLock());
Preconditions.CheckArgument(src.EndsWith(HdfsConstants.SeparatorDotSnapshotDir),
"%s does not end with %s", src, HdfsConstants.SeparatorDotSnapshotDir);
string dirPath = FSDirectory.NormalizePath(Sharpen.Runtime.Substring(src, 0, src.
Length - HdfsConstants.DotSnapshotDir.Length));
INode node = fsd.GetINode(dirPath);
INodeDirectory dirNode = INodeDirectory.ValueOf(node, dirPath);
DirectorySnapshottableFeature sf = dirNode.GetDirectorySnapshottableFeature();
if (sf == null)
{
throw new SnapshotException("Directory is not a snapshottable directory: " + dirPath
);
}
ReadOnlyList <Org.Apache.Hadoop.Hdfs.Server.Namenode.Snapshot.Snapshot> snapshots =
sf.GetSnapshotList();
int skipSize = ReadOnlyList.Util.BinarySearch(snapshots, startAfter);
skipSize = skipSize < 0 ? -skipSize - 1 : skipSize + 1;
int numOfListing = Math.Min(snapshots.Size() - skipSize, fsd.GetLsLimit());
HdfsFileStatus[] listing = new HdfsFileStatus[numOfListing];
for (int i = 0; i < numOfListing; i++)
{
Snapshot.Root sRoot = snapshots.Get(i + skipSize).GetRoot();
listing[i] = CreateFileStatus(fsd, src, sRoot.GetLocalNameBytes(), sRoot, BlockStoragePolicySuite
.IdUnspecified, Org.Apache.Hadoop.Hdfs.Server.Namenode.Snapshot.Snapshot.CurrentStateId
, false, INodesInPath.FromINode(sRoot));
}
return(new DirectoryListing(listing, snapshots.Size() - skipSize - numOfListing));
}
/// <summary>Create FileStatus with location info by file INode</summary>
/// <exception cref="System.IO.IOException"/>
private static HdfsLocatedFileStatus CreateLocatedFileStatus(FSDirectory fsd, string
fullPath, byte[] path, INode node, byte storagePolicy, int snapshot, bool isRawPath
, INodesInPath iip)
{
System.Diagnostics.Debug.Assert(fsd.HasReadLock());
long size = 0;
// length is zero for directories
short replication = 0;
long blocksize = 0;
LocatedBlocks loc = null;
bool isEncrypted;
FileEncryptionInfo feInfo = isRawPath ? null : fsd.GetFileEncryptionInfo(node, snapshot
, iip);
if (node.IsFile())
{
INodeFile fileNode = node.AsFile();
size = fileNode.ComputeFileSize(snapshot);
replication = fileNode.GetFileReplication(snapshot);
blocksize = fileNode.GetPreferredBlockSize();
bool inSnapshot = snapshot != Org.Apache.Hadoop.Hdfs.Server.Namenode.Snapshot.Snapshot
.CurrentStateId;
bool isUc = !inSnapshot && fileNode.IsUnderConstruction();
long fileSize = !inSnapshot && isUc?fileNode.ComputeFileSizeNotIncludingLastUcBlock
() : size;
loc = fsd.GetFSNamesystem().GetBlockManager().CreateLocatedBlocks(fileNode.GetBlocks
(snapshot), fileSize, isUc, 0L, size, false, inSnapshot, feInfo);
if (loc == null)
{
loc = new LocatedBlocks();
}
isEncrypted = (feInfo != null) || (isRawPath && fsd.IsInAnEZ(INodesInPath.FromINode
(node)));
}
else
{
isEncrypted = fsd.IsInAnEZ(INodesInPath.FromINode(node));
}
int childrenNum = node.IsDirectory() ? node.AsDirectory().GetChildrenNum(snapshot
) : 0;
INodeAttributes nodeAttrs = fsd.GetAttributes(fullPath, path, node, snapshot);
HdfsLocatedFileStatus status = new HdfsLocatedFileStatus(size, node.IsDirectory()
, replication, blocksize, node.GetModificationTime(snapshot), node.GetAccessTime
(snapshot), GetPermissionForFileStatus(nodeAttrs, isEncrypted), nodeAttrs.GetUserName
(), nodeAttrs.GetGroupName(), node.IsSymlink() ? node.AsSymlink().GetSymlink() :
null, path, node.GetId(), loc, childrenNum, feInfo, storagePolicy);
// Set caching information for the located blocks.
if (loc != null)
{
CacheManager cacheManager = fsd.GetFSNamesystem().GetCacheManager();
foreach (LocatedBlock lb in loc.GetLocatedBlocks())
{
cacheManager.SetCachedLocations(lb);
}
}
return(status);
}
/// <summary>
/// Relinquish locks held during computation for a short while
/// and reacquire them.
/// </summary>
/// <remarks>
/// Relinquish locks held during computation for a short while
/// and reacquire them. This will give other threads a chance
/// to acquire the contended locks and run.
/// </remarks>
/// <returns>true if locks were released and reacquired.</returns>
public virtual bool Yield()
{
// Are we set up to do this?
if (limitPerRun <= 0 || dir == null || fsn == null)
{
return(false);
}
// Have we reached the limit?
long currentCount = counts.GetFileCount() + counts.GetSymlinkCount() + counts.GetDirectoryCount
() + counts.GetSnapshotableDirectoryCount();
if (currentCount <= nextCountLimit)
{
return(false);
}
// Update the next limit
nextCountLimit = currentCount + limitPerRun;
bool hadDirReadLock = dir.HasReadLock();
bool hadDirWriteLock = dir.HasWriteLock();
bool hadFsnReadLock = fsn.HasReadLock();
bool hadFsnWriteLock = fsn.HasWriteLock();
// sanity check.
if (!hadDirReadLock || !hadFsnReadLock || hadDirWriteLock || hadFsnWriteLock || dir
.GetReadHoldCount() != 1 || fsn.GetReadHoldCount() != 1)
{
// cannot relinquish
return(false);
}
// unlock
dir.ReadUnlock();
fsn.ReadUnlock();
try
{
Sharpen.Thread.Sleep(sleepMilliSec, sleepNanoSec);
}
catch (Exception)
{
}
finally
{
// reacquire
fsn.ReadLock();
dir.ReadLock();
}
yieldCount++;
return(true);
}
/// <summary>Returns true if an IIP is within an encryption zone.</summary>
/// <remarks>
/// Returns true if an IIP is within an encryption zone.
/// <p/>
/// Called while holding the FSDirectory lock.
/// </remarks>
/// <exception cref="Org.Apache.Hadoop.FS.UnresolvedLinkException"/>
/// <exception cref="Org.Apache.Hadoop.Hdfs.Protocol.SnapshotAccessControlException"/
/// >
internal virtual bool IsInAnEZ(INodesInPath iip)
{
System.Diagnostics.Debug.Assert(dir.HasReadLock());
return(GetEncryptionZoneForPath(iip) != null);
}