SocketAddress remoteAddress = info.remoteAddress();
return readdir(xdr, securityHandler, remoteAddress);
}
public READDIR3Response readdir(XDR xdr, SecurityHandler securityHandler,
SocketAddress remoteAddress) {
READDIR3Response response = new READDIR3Response(Nfs3Status.NFS3_OK);
if (!checkAccessPrivilege(remoteAddress, AccessPrivilege.READ_ONLY)) {
response.setStatus(Nfs3Status.NFS3ERR_ACCES);
return response;
}
DFSClient dfsClient = clientCache.getDfsClient(securityHandler.getUser());
if (dfsClient == null) {
response.setStatus(Nfs3Status.NFS3ERR_SERVERFAULT);
return response;
}
READDIR3Request request = null;
try {
request = new READDIR3Request(xdr);
} catch (IOException e) {
LOG.error("Invalid READDIR request");
return new READDIR3Response(Nfs3Status.NFS3ERR_INVAL);
}
FileHandle handle = request.getHandle();
long cookie = request.getCookie();
if (cookie < 0) {
LOG.error("Invalid READDIR request, with negitve cookie:" + cookie);
return new READDIR3Response(Nfs3Status.NFS3ERR_INVAL);
}
long count = request.getCount();
if (count <= 0) {
LOG.info("Nonpositive count in invalid READDIR request:" + count);
return new READDIR3Response(Nfs3Status.NFS3_OK);
}
if (LOG.isDebugEnabled()) {
LOG.debug("NFS READDIR fileId: " + handle.getFileId() + " cookie: "
+ cookie + " count: " + count);
}
HdfsFileStatus dirStatus = null;
DirectoryListing dlisting = null;
Nfs3FileAttributes postOpAttr = null;
long dotdotFileId = 0;
try {
String dirFileIdPath = Nfs3Utils.getFileIdPath(handle);
dirStatus = dfsClient.getFileInfo(dirFileIdPath);
if (dirStatus == null) {
LOG.info("Can't get path for fileId:" + handle.getFileId());
return new READDIR3Response(Nfs3Status.NFS3ERR_STALE);
}
if (!dirStatus.isDir()) {
LOG.error("Can't readdir for regular file, fileId:"
+ handle.getFileId());
return new READDIR3Response(Nfs3Status.NFS3ERR_NOTDIR);
}
long cookieVerf = request.getCookieVerf();
if ((cookieVerf != 0) && (cookieVerf != dirStatus.getModificationTime())) {
if (aixCompatMode) {
// The AIX NFS client misinterprets RFC-1813 and will repeatedly send
// the same cookieverf value even across VFS-level readdir calls,
// instead of getting a new cookieverf for every VFS-level readdir
// call, and reusing the cookieverf only in the event that multiple
// incremental NFS-level readdir calls must be made to fetch all of
// the directory entries. This means that whenever a readdir call is
// made by an AIX NFS client for a given directory, and that directory
// is subsequently modified, thus changing its mtime, no later readdir
// calls will succeed from AIX for that directory until the FS is
// unmounted/remounted. See HDFS-6549 for more info.
LOG.warn("AIX compatibility mode enabled, ignoring cookieverf " +
"mismatches.");
} else {
LOG.error("CookieVerf mismatch. request cookieVerf: " + cookieVerf
+ " dir cookieVerf: " + dirStatus.getModificationTime());
return new READDIR3Response(Nfs3Status.NFS3ERR_BAD_COOKIE);
}
}
if (cookie == 0) {
// Get dotdot fileId
String dotdotFileIdPath = dirFileIdPath + "/..";
HdfsFileStatus dotdotStatus = dfsClient.getFileInfo(dotdotFileIdPath);
if (dotdotStatus == null) {
// This should not happen
throw new IOException("Can't get path for handle path:"
+ dotdotFileIdPath);
}
dotdotFileId = dotdotStatus.getFileId();
}
// Get the list from the resume point
byte[] startAfter;
if(cookie == 0 ) {
startAfter = HdfsFileStatus.EMPTY_NAME;
} else {
String inodeIdPath = Nfs3Utils.getFileIdPath(cookie);
startAfter = inodeIdPath.getBytes();
}
dlisting = listPaths(dfsClient, dirFileIdPath, startAfter);
postOpAttr = Nfs3Utils.getFileAttr(dfsClient, dirFileIdPath, iug);
if (postOpAttr == null) {
LOG.error("Can't get path for fileId:" + handle.getFileId());
return new READDIR3Response(Nfs3Status.NFS3ERR_STALE);
}
} catch (IOException e) {
LOG.warn("Exception ", e);
return new READDIR3Response(Nfs3Status.NFS3ERR_IO);
}
/**
* Set up the dirents in the response. fileId is used as the cookie with one
* exception. Linux client can either be stuck with "ls" command (on REHL)
* or report "Too many levels of symbolic links" (Ubuntu).
*
* The problem is that, only two items returned, "." and ".." when the
* namespace is empty. Both of them are "/" with the same cookie(root
* fileId). Linux client doesn't think such a directory is a real directory.
* Even though NFS protocol specifies cookie is an opaque data, Linux client
* somehow doesn't like an empty dir returns same cookie for both "." and
* "..".
*
* The workaround is to use 0 as the cookie for "." and always return "." as
* the first entry in readdir/readdirplus response.
*/
HdfsFileStatus[] fstatus = dlisting.getPartialListing();
int n = (int) Math.min(fstatus.length, count-2);
boolean eof = (n < fstatus.length) ? false : (dlisting
.getRemainingEntries() == 0);
Entry3[] entries;
if (cookie == 0) {
entries = new Entry3[n + 2];
entries[0] = new READDIR3Response.Entry3(postOpAttr.getFileId(), ".", 0);
entries[1] = new READDIR3Response.Entry3(dotdotFileId, "..", dotdotFileId);
for (int i = 2; i < n + 2; i++) {
entries[i] = new READDIR3Response.Entry3(fstatus[i - 2].getFileId(),
fstatus[i - 2].getLocalName(), fstatus[i - 2].getFileId());
}
} else {
// Resume from last readdirplus. If the cookie is "..", the result
// list is up the directory content since HDFS uses name as resume point.
entries = new Entry3[n];
for (int i = 0; i < n; i++) {
entries[i] = new READDIR3Response.Entry3(fstatus[i].getFileId(),
fstatus[i].getLocalName(), fstatus[i].getFileId());
}
}
DirList3 dirList = new READDIR3Response.DirList3(entries, eof);
return new READDIR3Response(Nfs3Status.NFS3_OK, postOpAttr,
dirStatus.getModificationTime(), dirList);
}