/** Create directory entries for every item */
boolean mkdirs(String src) {
src = normalizePath(new UTF8(src));
// Use this to collect all the dirs we need to construct
Vector v = new Vector();
// The dir itself
v.add(src);
// All its parents
String parent = DFSFile.getDFSParent(src);
while (parent != null) {
v.add(parent);
parent = DFSFile.getDFSParent(parent);
}
// Now go backwards through list of dirs, creating along
// the way
boolean lastSuccess = false;
int numElts = v.size();
for (int i = numElts - 1; i >= 0; i--) {
String cur = (String) v.elementAt(i);
INode inserted = unprotectedMkdir(cur);
if (inserted != null) {
logEdit(OP_MKDIR, new UTF8(inserted.computeName()), null);
lastSuccess = true;
} else {
lastSuccess = false;
}
}
return lastSuccess;
}
/** Save the contents of the FS image */
void saveFSImage(File fullimage, File edits) throws IOException {
File curFile = new File(fullimage, FS_IMAGE);
File newFile = new File(fullimage, NEW_FS_IMAGE);
File oldFile = new File(fullimage, OLD_FS_IMAGE);
//
// Write out data
//
DataOutputStream out =
new DataOutputStream(new BufferedOutputStream(new FileOutputStream(newFile)));
try {
out.writeInt(rootDir.numItemsInTree() - 1);
rootDir.saveImage("", out);
} finally {
out.close();
}
//
// Atomic move sequence
//
// 1. Move cur to old
curFile.renameTo(oldFile);
// 2. Move new to cur
newFile.renameTo(curFile);
// 3. Remove pending-edits file (it's been integrated with newFile)
edits.delete();
// 4. Delete old
oldFile.delete();
}
long computeContentsLength() {
long total = computeFileLength();
for (Iterator it = children.values().iterator(); it.hasNext(); ) {
INode child = (INode) it.next();
total += child.computeContentsLength();
}
return total;
}
int numItemsInTree() {
int total = 0;
for (Iterator it = children.values().iterator(); it.hasNext(); ) {
INode child = (INode) it.next();
total += child.numItemsInTree();
}
return total + 1;
}
/**
* Called after a request has been handled.
*
* @param reval the request evaluator that handled the request
*/
public void commit(RequestEvaluator reval, SessionManager smgr) {
if (modifiedInRequest || cacheLastModified != cacheNode.lastModified()) {
if (!registered) {
smgr.registerSession(this);
registered = true;
}
modifiedInRequest = false;
cacheLastModified = cacheNode.lastModified();
}
}
/**
* Collect all the blocks at this INode and all its children. This operation is performed after
* a node is removed from the tree, and we want to GC all the blocks at this node and below.
*/
void collectSubtreeBlocks(Vector v) {
if (blocks != null) {
for (int i = 0; i < blocks.length; i++) {
v.add(blocks[i]);
}
}
for (Iterator it = children.values().iterator(); it.hasNext(); ) {
INode child = (INode) it.next();
child.collectSubtreeBlocks(v);
}
}
String computeName() {
if (parent != null) {
return parent.computeName() + "/" + name;
} else {
return name;
}
}
INode getNode(Vector components, int index) {
if (!name.equals((String) components.elementAt(index))) {
return null;
}
if (index == components.size() - 1) {
return this;
}
// Check with children
INode child = (INode) children.get(components.elementAt(index + 1));
if (child == null) {
return null;
} else {
return child.getNode(components, index + 1);
}
}
/** Set the cache node for this session. */
public void setCacheNode(INode node) {
if (node == null) {
throw new NullPointerException("cache node is null");
}
this.cacheNode = node;
this.cacheLastModified = cacheNode.lastModified();
}
void saveImage(String parentPrefix, DataOutputStream out) throws IOException {
String fullName = "";
if (parent != null) {
fullName = parentPrefix + "/" + name;
new UTF8(fullName).write(out);
if (blocks == null) {
out.writeInt(0);
} else {
out.writeInt(blocks.length);
for (int i = 0; i < blocks.length; i++) {
blocks[i].write(out);
}
}
}
for (Iterator it = children.values().iterator(); it.hasNext(); ) {
INode child = (INode) it.next();
child.saveImage(fullName, out);
}
}
/** Check whether the filepath could be created */
public boolean isValidToCreate(UTF8 src) {
String srcs = normalizePath(src);
synchronized (rootDir) {
if (srcs.startsWith("/") && !srcs.endsWith("/") && rootDir.getNode(srcs) == null) {
return true;
} else {
return false;
}
}
}
boolean unprotectedAddFile(UTF8 name, Block blocks[]) {
synchronized (rootDir) {
if (blocks != null) {
// Add file->block mapping
for (int i = 0; i < blocks.length; i++) {
activeBlocks.add(blocks[i]);
}
}
return (rootDir.addNode(name.toString(), blocks) != null);
}
}
/** Get the blocks associated with the file */
public Block[] getFile(UTF8 src) {
waitForReady();
synchronized (rootDir) {
INode targetNode = rootDir.getNode(src.toString());
if (targetNode == null) {
return null;
} else {
return targetNode.blocks;
}
}
}
/**
* Get a listing of files given path 'src'
*
* <p>This function is admittedly very inefficient right now. We'll make it better later.
*/
public DFSFileInfo[] getListing(UTF8 src) {
String srcs = normalizePath(src);
synchronized (rootDir) {
INode targetNode = rootDir.getNode(srcs);
if (targetNode == null) {
return null;
} else {
Vector contents = new Vector();
targetNode.listContents(contents);
DFSFileInfo listing[] = new DFSFileInfo[contents.size()];
int i = 0;
for (Iterator it = contents.iterator(); it.hasNext(); i++) {
listing[i] = new DFSFileInfo((INode) it.next());
}
return listing;
}
}
}
/**
* Creates a new Session object.
*
* @param sessionId ...
* @param app ...
*/
public Session(String sessionId, Application app) {
this.sessionId = sessionId;
this.app = app;
this.uid = null;
this.userHandle = null;
cacheNode = new TransientNode(app, "session");
cacheLastModified = cacheNode.lastModified();
// HACK - decrease timestamp by 1 to notice modifications
// taking place immediately after object creation
onSince = System.currentTimeMillis() - 1;
lastTouched = lastModified = onSince;
}
/** Attach the given user node to this session. */
public void login(INode usernode) {
if (usernode == null) {
userHandle = null;
uid = null;
} else {
userHandle = ((Node) usernode).getHandle();
uid = usernode.getElementName();
}
lastModified = System.currentTimeMillis();
modifiedInRequest = true;
}
Block[] unprotectedDelete(UTF8 src) {
synchronized (rootDir) {
INode targetNode = rootDir.getNode(src.toString());
if (targetNode == null) {
return null;
} else {
//
// Remove the node from the namespace and GC all
// the blocks underneath the node.
//
if (!targetNode.removeNode()) {
return null;
} else {
Vector v = new Vector();
targetNode.collectSubtreeBlocks(v);
for (Iterator it = v.iterator(); it.hasNext(); ) {
Block b = (Block) it.next();
activeBlocks.remove(b);
}
return (Block[]) v.toArray(new Block[v.size()]);
}
}
}
}
boolean unprotectedRenameTo(UTF8 src, UTF8 dst) {
synchronized (rootDir) {
INode removedNode = rootDir.getNode(src.toString());
if (removedNode == null) {
return false;
}
removedNode.removeNode();
if (isDir(dst)) {
dst = new UTF8(dst.toString() + "/" + new File(src.toString()).getName());
}
INode newNode = rootDir.addNode(dst.toString(), removedNode.blocks);
if (newNode != null) {
newNode.children = removedNode.children;
for (Iterator it = newNode.children.values().iterator(); it.hasNext(); ) {
INode child = (INode) it.next();
child.parent = newNode;
}
return true;
} else {
rootDir.addNode(src.toString(), removedNode.blocks);
return false;
}
}
}
INode unprotectedMkdir(String src) {
synchronized (rootDir) {
return rootDir.addNode(src, null);
}
}
/** Check whether the path specifies a directory */
public boolean isDir(UTF8 src) {
synchronized (rootDir) {
INode node = rootDir.getNode(normalizePath(src));
return node != null && node.isDir();
}
}